TY - JOUR T1 - Polycations and polyanions in SARS-CoV-2 infection JF - Medical Hypotheses Volume 146 Y1 - 2021 A1 - Issac Ginsburg A1 - Fibach, Eithan AB -

We hypothesize that polycations, such as nuclear histones, released by neutrophils COVID-19 aggravate COVID-19 by multiple mechanisms: (A) Neutralization of the electrostatic repulsion between the virus particles and the cell membrane, thereby enhancing receptor-mediated entry. (B) Binding to the virus particles, thereby inducing opsonin-mediated endocytosis. (C) Adding to the cytotoxicity, in conjunction with oxidants, cytokines and other pro-inflammatory substances secreted by cells of the innate immunity system. These effects may be alleviated by the administration of negatively charged polyanions such as heparins and heparinoids.

VL - 146 UR - https://www.sciencedirect.com/science/article/pii/S0306987720333612?via%3Dihub ER - TY - JOUR T1 - Longitudinal patterns of cytokine expression at the individual level in humans after laparoscopic sleeve gastrectomy JF - Journal of Cellular and Molecular Medicine Y1 - 2020 A1 - Uriel Trahtemberg A1 - Fares Darawshe A1 - Ram Elazary A1 - Issac Ginsburg A1 - Michael Beil A1 - Peter Vernon van Heerden A1 - Sigal Sviri AB -

The study of the human response to injury has been hampered by the inherent heterogeneity in the models and methods used. By studying a standard injury longitudinally, using individual patient‐level analysis, we endeavoured to better describe its dynamics. We analysed clinical variables, clinical laboratory and plasma cytokines from 20 patients at five time points. Clustering analysis showed two prototype patterns of cytokine behaviour: a concordant type, where cytokines behave the same way for all patients (notably IL‐0 and TNFα), and a variable type, where different patterns of expression are seen for different patients (notably IL‐8, IL‐6 and IL‐1RA). Analysis of the cytokines at the individual patient‐level showed a strong four‐way correlation between IL‐1RA, GCSF, MIP‐1β and MCP‐1. As it holds for most patients and not just on average, this suggests that they form a network which may play a central role in the response to gastro‐intestinal injuries in humans. In conclusion, the longitudinal analysis of cytokines in a standard model allowed the identification of their underlying patterns of expression. We propose that the two prototype patterns shown may reflect the mechanism that separates the common and individual aspects of the injury response.

VL - 24 UR - https://onlinelibrary.wiley.com/doi/full/10.1111/jcmm.15309 IS - 12 ER - TY - JOUR T1 - A Novel Concept May Explain How Immune Complexes Interact with Highly Cationic Histones Released by Activated Neutrophils Nets Act in Synergy with the Plethora of Neutrophils Pro-Inflammatory Agonists Leading to the Development of Autoimmune Nephritis -A JF - Journal of Clinical Nephrology & Kidney Diseases Y1 - 2020 A1 - Issac Ginsburg A1 - Erez Koren A1 - Ido Ben Dov AB -

 

Recent studies have pointed out that highly cationic histones released by PMNs netosis may be major agents in autoimmune lupus since they have high affinity to various kidney sites and can be expected to play a key role in autoimmune glomerular disease.

Similarly to antibodies, cationic peptides such a nuclear histone can also act as potent opsonic agents capable of binding by strong electrostatic forces to negatively charged domains in immune complexes and in complement components resulting in their endocytosis and deposition in various parts of the kidney. It is also proposed that to prevent such events, highly anionic heparin and heparinoids, may be effective drugs since these may effectively neutralize histones activities but provided that agents such as steroids, methotrexate and colchicine, all potent inhibitors of neutrophils functions, and antibodies to TH1 cytokines be essential to treat nephritis and to prevent kidney failure. However, the main cause of kidney damage is eventually caused by the plethora of toxic pro inflammatory agents delivered by activated neutrophils and macrophages.

 

VL - 5 UR - http://www.remedypublications.com/open-access/a-novel-concept-may-explain-how-immune-complexes-interact-with-5927.pdf IS - 1 ER - TY - JOUR T1 - In Lupus Erythematosus the Deposition of Immune Complexes in Tissues Is Mediated via Nuclear Histones Released by Neutrophils Nets but the Main Damage to Hosts Tissues Is Caused by the Plethora of Toxic Pro Inflammatory Agents Released by Activated Neutro JF - Open Journal of Rheumatology and Autoimmune Diseases Y1 - 2020 A1 - Issac Ginsburg AB -

The present study offers a novel approach that may explain the mechanisms of pathogenicity of the auto immune destructive disorder, Lupus Erythematosus. It is proposed that deposition of immune complexes and complement components in tissue is mediated by highly cationic histones released from neutrophils nets the phenomenon of netosis. Histones act a potent opsonic factor similar to antibodies which interact by strong electrostatic forces with negatively-charged domains in immune complexes and complements facilitating their deposition and also their internalization by hosts’ cells. However, the main cause of cell and tissue damage in Lupus is inflicted by the plethora of toxic pro inflammatory agonists released by neutrophils and by macrophages recruited to inflamed tissues by cytokines. The melioration of tissue damage may be initiated by highly anionic heparins, which neutralizes histones’ action if also combined with steroids, colchicin and methtorxate as well as by other agents which retard leukocytes migration and functions.

VL - 10 UR - https://www.scirp.org/journal/paperinformation.aspx?paperid=100586 IS - 2 ER - TY - JOUR T1 - A novel aspect may explain the mechanisms of pathogenicity of rheumatic fever, a multifactorial, autoimmune, infectious and inflammatory disorder which “licks the joints and bites the heart”: A working hypothesis JF - Medical Hypotheses Y1 - 2020 A1 - Issac Ginsburg A1 - Mark Feldman AB -

A novel hypothesis is presented to explain the pathogenesis of the multifactorial autoimmune disorder rheumatic fever (RF). It involves a synergistic interaction among streptococcal toxins, their cell wall components, M protein, immune complexes, complement components, cationic histones. These agents can act with cationic histones released by neutrophils during NETosis and bacteriolysis and can function as opsonic agents possessing properties similar to antibodies. Cationic histones can interact by strong electrostatic forces with negatively- charged domains on immune complexes and complement components. This allows their deposition and endocytosis in the myocardium, the heart valves, and in the joints. However, the main cause of cell and tissue damage observed in RF is due to a synergism among the plethora of pro-inflammatory substances released by activated neutrophils and macrophages. Cell damage may be mitigated to some extent by anionic heparins, heparinoids, and by anti-inflammatory drugs such as corticosteroids which counteract neutrophils and macrophage chemotaxis induced by cytokines.

VL - 144 UR - https://www.sciencedirect.com/science/article/pii/S030698772031402X ER - TY - JOUR T1 - A Novel Approach That May Explain the Role of Staphylococcus aureus, Polycations, Neutrophils Pro-Inflammatory Agonists and the Bacteriolysis and Auto Immune Phenomena as Possible Major Events in the Pathogenesis of Atopic Dermatitis: A Working Hypothesis JF - Journal of Clinical & Experimental Dermatology Research Y1 - 2019 A1 - Isaac Ginsburg A1 - Erez Koren AB -

 

The aim of the present short communication is to shed a novel light on the auto immune disorder atopic dermatitis by discussing the possible role played by the plethora of toxic agents released by  Staphylococcus aureus which can act in a tight synergism with neutrophils derived cationic polyelectrolytes  as related to the pathogenesis of atopic dermatitis (AD) [1,2]. This disorder results in  inflammation of the  skin characterized by itchiness,  red  skin,  a  rash,  by   the  accumulations  of  large numbers of Staphylococcus  aureus  their toxins [2] and pro- inflammatory agents secreted by migrating neutrophiles [3], are considered the main cause of AD pathogenicity.

 

VL - 10 UR - https://www.longdom.org/abstract/a-novel-approach-that-may-explain-the-role-of-staphylococcus-aureus-polycations-neutrophils-proinflammatory-agonists-and-44503.html IS - 5 ER - TY - JOUR T1 - Is Tissue Damage caused in Group A Streptococcal Infections Augmented by Synergizing with Neutrophils’ Pro-inflammatory Products? JF - Microbiology & Infectious Diseases Y1 - 2019 A1 - Isaac Ginsburg A1 - Erez Koren AB -

Catalase-negative penicillin-sensitive group A hemolytic streptococci (GAS) are multifactorial microorganisms, which do not produce a unique damage-associated molecular patterns which if effectively neutralized might effectively stop their pathogenicity. GAS is involved in the pathogenicity of pharangitis, tonsillitis, rheumatic fever, arthritis, necrotizing fasciitis (NF), toxic shock syndrome and also in sepsis. GAS-induced NF is quite a rare but dangerous and deadly infection, which most commonly occurs in the arms, legs and abdominal wall and is fatal in 30%-40% of cases. GAS, which possess surface capsular polysaccharide and antigenic M and T proteins, arrive at the inflammatory areas by generating spreading factors such as hyaluronidase, DNase and streptokinaseactivated plasmin. GAS can spread in tissues and avidly adhere to membranes of target cells to deliver a nonimmunogenic cell bound hemolysin (CBH) upon cells’ membrane phospholipids to induce a penetrating membrane damage (“a kiss of Death”). Two additional potent extracellular hemolysins, Streptolysin O (SLO) and a nonimmunogenic streptolysin S (SLS) produced can injure neutrophils (PMNs), which are recruited to the infected sites in large numbers. However, PMNs can engage in phagocytosis and also undergo activation to release various proinflammatory agents including NADPH-generated superoxide which dismutates to H2 O2 and with myeloperoxidase (MPO) which forms toxic HOCl upon interaction with halides. Activated PMNs also deliver highly cationic peptides such as LL37, cationic elastase, cathepsins and nuclear histone, which interact electrostatically with negatively-charged membrane sites forming membrane lesions. PMNs also secrete many acid hydrolases, several Th1 cytokines and chemokines, which recruit more PMNs. Similarly, to beta-lactams antibiotics, cationic peptides can also activate bacteriolysis and trigger the release of the pro-inflammatory agents lipoteichoic acid (LTA) and peptidoglycan (PPG). We hereby propose that in infectious and inflammatory sites GAS and PMNs exo-products and also microbial cellwall structures might all act synergistically to cause cell and tissue damage. Cell damage might be ameliorated by appropriate cocktails of anti-inflammatory agents. also, containing highly negatively charged heparin 23.

VL - 2019; 3 UR - http://scivisionpub.com/pdfs/is-tissue-damage-caused-in-group-a-streptococcal-infections-augmented-by-synergizing-with-neutrophils-proinflammatory-products-694.pdf IS - 1 ER - TY - JOUR T1 - Pro-inflammatory agents released by pathogens, dying host cells, and neutrophils act synergistically to destroy host tissues: a working hypothesis JF - Journal of Inflammation Research Y1 - 2019 A1 - Isaac Ginsburg A1 - M. Koren A1 - James Varani AB -

Abstract: We postulate that the extensive cell and tissue damage inflicted by many infectious, inflammatory and post-inflammatory episodes is an enled result of a synergism among the invading microbial agents, host neutrophils and dead and dying cells in the nidus. Microbial toxins and other metabolites along with the plethora of pro-inflammatory agents released from activated neutrophils massively recruited to the infectious sites and high levels of cationic histones, other cationic peptides, proteinases and Th1 cytokines released from activated polymorphonuclear neutrophils (PMNs) and from necrotized tissues may act in concert (synergism) to bring about cell killing and tissue destruction. Multiple, diverse interactions among the many potential pro-inflammatory moieties have been described in these complex lesions. Such infections are often seen in the skin and aerodigestive tract where the tissue is exposed to the environment, but can occur in any tissue. Commonly, the tissue-destructive infections are caused by group A streptococci, pneumococci, Staphylococcus aureus, meningococci, Escherichia coli and Shigella, although many other microbial species are seen on occasion. All these microbial agents are characterized by their ability to recruit large numbers of PMNs. Given the complex nature of the disease process, it is proposed that, to treat these multifactorial disorders, a “cocktail” of anti-inflammatory agents combined with non-bacteriolytic antibiotics and measures to counteract the critical toxic role of cationic moieties might prove more effective than a strategy based on attacking the bacteria alone.

VL - 12 UR - https://www.ncbi.nlm.nih.gov/pubmed/30774411 ER - TY - JOUR T1 - Polyphenols Inhibit Candida albicans and Streptococcus mutans Biofilm Formation. JF - Dentistry Journal Y1 - 2019 A1 - Yogi Farkash A1 - Mark Feldman A1 - Isaac Ginsburg A1 - Doreen Steinberg A1 - Miriam Shalish AB -

Background:Streptococcus mutans (S. mutans) and Candida albicans (C. albicans) are two major contributors to dental caries. They have a symbiotic relationship, allowing them to create an enhanced biofilm. Our goal was to examine whether two natural polyphenols (Padma hepaten (PH) and a polyphenol extraction from green tea (PPFGT)) could inhibit the caries-inducing properties of S. mutans and C. albicans. Methods: Co-species biofilms of S. mutans and C. albicans were grown in the presence of PH and PPFGT. Biofilm formation was tested spectrophotometrically. Exopolysaccharides (EPS) secretion was quantified using confocal scanning laser microscopy. Biofilm development was also tested on orthodontic surfaces (Essix) to assess biofilm inhibition ability on such an orthodontic appliance. Results: PPFGT and PH dose-dependently inhibited biofilm formation without affecting the planktonic growth. We found a significant reduction in biofilm total biomass using 0.625 mg/mL PPFGT and 0.16 mg/mL PH. A concentration of 0.31 mg/mL PPFGT and 0.16 mg/mL PH inhibited the total cell growth by 54% and EPS secretion by 81%. A reduction in biofilm formation and EPS secretion was also observed on orthodontic PVC surfaces. Conclusions: The polyphenolic extractions PPFGT and PH have an inhibitory effect on S. mutans and C. albicans biofilm formation and EPS secretion.

VL - 7 UR - https://www.mdpi.com/2304-6767/7/2/42 IS - 2 ER - TY - JOUR T1 - Effect of fixed orthodontic appliances on nonmicrobial salivary parameters. JF - The Angle Orthodontist Y1 - 2018 A1 - IP. Zogakis A1 - Koren, E. A1 - S. Gorelik A1 - Ginsburg, I. A1 - M. Shalish AB -

Objectives: To examine possible changes in the levels of salivary antioxidants, C-reactive protein (CRP), cortisol, pH, proteins, and blood in patients treated with fixed orthodontic appliances. Materials and Methods: Salivary samples from 21 orthodontic patients who met specific inclusion criteria were collected before the beginning of orthodontic treatment (T0; baseline), 1 hour after bonding (T1), and 4–6 weeks after bonding (T2). Oxidant-scavenging ability (OSA) was quantified using a luminol-dependent chemiluminescence assay. Cortisol and CRP levels were measured using immunoassay kits. pH levels and presence of proteins and blood in the samples were quantified using strip-based tests. Results: A significant decrease in salivary pH was observed after bonding (P ¼ .013). An increase in oxidant-scavenging abilities during orthodontic treatment was detected, but the change was not statistically significant. Cortisol and CRP levels slightly increased after bonding, but the difference was small without statistical significance. Changes in the presence of proteins and blood were also insignificant. Conclusions: Exposure to fixed orthodontic appliances did not show a significant effect on salivary parameters related to inflammation or stress, with the exception of a significant but transient pH decrease after bonding. (Angle Orthod. 2018;88:806–811.)

VL - 88 UR - https://www.ncbi.nlm.nih.gov/pubmed/29911908 IS - 6 ER - TY - JOUR T1 - Green Tea Polyphenols and Padma Hepaten Inhibit Candida albicansBiofilm Formation JF - Evidence-Based Complementary and Alternative Medicine Y1 - 2018 A1 - Y. Farkash A1 - Feldman, M. A1 - Ginsburg, I. A1 - Steinberg, D. A1 - M. Shalish AB -

Candida albicans (C. albicans) is the most prevalent opportunistic human pathogenic fungus and can cause mucosal membrane infections and invade the blood. In the oral cavity, it can ferment dietary sugars, produce organic acids and therefore has a role in caries development. In this study, we examined whether the polyphenol rich extractions Polyphenon from green tea (PPFGT) and Padma Hepaten (PH) can inhibit the caries-inducing properties of C. albicans. Biofilms of C. albicans were grown in the presence of PPFGT and PH. Formation of biofilms was tested spectrophotometrically after crystal violet staining. Exopolysaccharides (EPS) secretion was quantified using confocal scanning laser microscopy (CSLM). Treated C. albicans morphology was demonstrated using scanning electron microscopy (SEM). Expression of virulence-related genes was tested using qRT-PCR. Development of biofilm was also tested on an orthodontic surface (Essix) to assess biofilm inhibition ability on such appliances. Both PPFGT and PH dose-dependently inhibited biofilm formation, with no inhibition on planktonic growth. The strongest inhibition was obtained using the combination of the substances. Crystal violet staining showed a significant reduction of 45% in biofilm formation using a concentration of 2.5mg/ml PPFGT and 0.16mg/ml PH. A concentration of 1.25 mg/ml PPFGT and 0.16 mg/ml PH inhibited candidal growth by 88% and EPS secretion by 74% according to CSLM. A reduction in biofilm formation and in the transition from yeast to hyphal morphotype was observed using SEM. A strong reduction was found in the expression of hwp1, eap1, and als3 virulence associated genes. These results demonstrate the inhibitory effect of natural PPFGT polyphenolic extraction on C. albicans biofilm formation and EPS secretion, alone and together with PH. In an era of increased drug resistance, the use of phytomedicine to constrain biofilm development, without killing host cells, may pave the way to a novel therapeutic concept, especially in children as orthodontic patients.

VL - 2018 ER - TY - JOUR T1 - The Pathogenesis of Sepsis: “If We Cannot beat them Alone Join Them?” JF - International Journal of Microbiology & Infectious Diseases Y1 - 2018 A1 - M. Korem A1 - Koren, E. A1 - Ginsburg, I. AB -

 

 

 Sepsis and septic shock are probably the least understood human disorders which worldwide take the lives of millions of patients. Sepsis may be defined as a multifactorial synergistic phenomenon where no unique damage-associated molecular patterns –alarming is identified which if successfully neutralized, might mitigate and protects against death in sepsis. 

Microorganisms which invade the blood stream may activate neutrophils to adhere to endothelial cells and to form oxidant – dependent nets rich in highly toxic nuclear histones claimed to be the main cause of death in sepsis due to the dysregulation of endothelial functions. However, the histone saga was recently critically debated since high levels circulating histones are also found in many clinical disorders unrelated to sepsis, therefore, histones may not be considered as a unique damage-associated molecular patterns- alarming but as additional markers of severe cell damage. 

We hereby argue that the main cause of tissue damage in sepsis may be an end result of a synergism between the numerous neutrophils pro inflammatory agents and the multiplicity of similar pro inflammatory agents generated by hemolytic steptoccocci and by additional pathogenic microorganism which recruit large numbers PMNs to the inflammatory sites. It is recommended that in sepsis caused by hemolytic streptococci and by additional toxigenic bacteria, a use of cocktails of antagonists might be more beneficial therapeutic strategies and this in view of the total failure to treat sepsis only by administrations of single antagonists. Also, targeting PMNs by immunological strategies should be sought for, to mitigate synergies between leukocytes and microbial cells.

 

VL - 2 UR - http://cmepub.com/pdfs/the-pathogenesis-of-sepsis-if-we-cannot-beat-them-alone-join-them-388.pdf IS - 3 ER - TY - JOUR T1 - Bacteriolysis – a mere laboratory curiosity? JF - Critical Reviews in Microbiology Y1 - 2018 A1 - Ginsburg, I. A1 - Koren, E. AB -

 

The role of bacteriolysis in the pathophysiology of microbial infections dates back to 1893 when

Buchner and Pfeiffer reported for the first time the lysis of bacteria by immune serum and related

this phenomenon to the immune response. Later on, basic anti-microbial peptides and certain

beta-lactam antibiotics have been shown not only to kill microorganisms but also to induce bacteriolysis

and the release of cell-wall components.

In 2009, a novel paradigm was offered suggesting that the main cause of death in sepsis is due

to the exclusive release from activated human phagocytic neutrophils (PMNs) traps adhering

upon endothelial cells of highly toxic nuclear histone. Since activated PMNs also release a plethora

of pro-inflammatory agonists, it stands to reason that these may act in synergy with histone

to damage cells. Since certain beta lactam antibiotics may induce bacteriolysis, it is questioned

whether these may aggravate sepsis patient's condition. Enigmatically, since the term bacteriolysis

and its possible involvement in sepsis is hardly ever mentioned in the extensive clinical

articles and reviews dealing with critical care, we hereby aim to refresh the concept of bacteriolysis

and its possible role in the pathogenesis of post infectious sequelae.

 

UR - https://doi.org/10.1080/1040841X.2018.1473332 ER - TY - JOUR T1 - Are histones real pathogenic agents in sepsis? JF - NATURE REVIEWS - IMMUNOLOGY Y1 - 2017 A1 - Ginsburg, I. A1 - Koren, E. AB -

 

We read with interest the recent Review article by van der Poll et al.1(The immunopathology of sepsis and potential therapeutic targets. Nat. Rev. Immunol. 17, 407–420 (2017)).This Review article describes various immunopathological aspects of sepsis and relevant targets as potential therapeutics. Unfortunately, we feel the authors failed to acknowledge highly relevant published data related to the possible pathogenic role of histones in sepsis.

In 2009, a paper by Xu et al.2, published in Nature Medicine, claimed that the main cause of death in sepsis is the release of highly toxic histones from neutrophils, possibly from those activated to make neutrophil extracellular traps3. Xu and co-workers also showed that the toxicity of histones could be abolished by either heparin, activated protein C or antibodies to histones. However, despite being an important new insight, this study was not cited in the Review by van der Poll and colleagues. Since this study, several other papers have been published showing high levels of circulating histones in many clinical disorders unrelated to sepsis3,4,5,6,7. This has led to the suggestion that histones are not unique inflammation-inducing alarmins (also known as damage-associated molecular patterns (DAMPs)) but are actually markers of cell damage8,9. Notably, in the context of sepsis, highly toxic cationic histones may function not alone but in synergy with oxidants and a range of pro-inflammatory agonists that are also released from activated neutrophils10,11,12,13. Again, none of these publications was acknowledged in the Review by van der Poll and colleagues.

We believe this important information on the possible role of histones in sepsis should have been acknowledged in this Review to encourage unbiased reporting and scholarly debate14.

 

UR - https://www.nature.com/articles/nri.2017.156 ER - TY - JOUR T1 - Tissue damage in post infectious sequelae is caused by a synergism between microbial and neutrophils-derived agonists: a concern for a disregard for already published data JF - Journal of Emerging and Rare Diseases Y1 - 2017 A1 - Ginsburg, I. A1 - Koren, E. A1 - Van Heerden, V. AB -

Post infectious sequelae such as sepsis and septic shock are poorly understood and annually take the lives of millions over the world. Severe microbial infections caused by Gram Positive and Gram Negative bacteria and by fungi are the main causes, which are aggravated by the rapid development of antibiotic resistance. It is unfortunate that today all the clinical trials of sepsis which tested the efficacy of single antagonists failed. Sepsis was recently redefined as a synergistic multifactorial episode where no unique alarmin had been identified, which if inhibited could control the deleterious biochemical and immune immunological events characteristic of sepsis. An apparent “breakthrough “in our understanding of sepsis pathogenicity was published in 2009 in Nature Medicine arguing that the main cause of mortality in sepsis is the release from neutrophils (PMNs) nets of highly toxic nuclear histone. This caused endothelial cell dysregulation leading to organ failure. However, this concept downplays the concept that concomitantly with the activation of PMNs, a plethora of additional proinflammatory agents is also released. These can act in synergy with histone to injure cells. Furthermore, since many additional clinical disorders not related to sepsis also reported high levels of circulating histones, this toxic agent may be considered just another marker of cell damage. The failure to treat sepsis by the administration of only single antagonists should be replaced by cocktails of appropriate anti inflammatory agents.

VL - 1 UR - https://www.boffinaccess.com/open-access-journals/journal-of-emerging-and-rare-diseases/jer-1-101.pdf IS - 1 ER - TY - ICOMM T1 - Sepsis Pathogenicity and Histones: Are we “Re-discovering the Wheel”? Y1 - 2017 A1 - Ginsburg, I. A1 - Koren, E. A1 - Varani, J. A1 - Kohen, R. AB -

It is alarming that today clinicians are still helpless trying to cope with life-threatening sequelae of severe microbial infections, which very often terminates in sepsis, septic shock and death. According to CDC (The Centers for Disease Control and Prevention) today the annual incidence of sepsis in the USA affects as many as 7,50,000 hospitalized patients and mortality rates are about 40% [1]. As of today, all the clinical trials of sepsis, which had tried the efficacy of only a single antagonist at a time, had failed to protect against septic shock, a disorder obviously caused by multi-factorial processes. Even the “hope of sepsis“, activated protein C (APC), has recently been discontinued. Today, no effective treatment for sepsis is available and the morality rates are climbing steadily also because of the rapid acquisition of antibiotic resistance.

UR - http://smgebooks.com/sepsis/chapters/SEP-17-13.pdf IS - Sepsis ER - TY - JOUR T1 - From amino acids polymers, antimicrobial peptides, and histones, to their possible role in the pathogenesis of septic shock: a historical perspective JF - Journal of Inflammation Research Y1 - 2017 A1 - Ginsburg, I. A1 - Van Heerden, V. A1 - Koren, E. AB -

This paper describes the evolution of our understanding of the biological role played by synthetic and natural antimicrobial cationic peptides and by the highly basic nuclear histones as modulators of infection, postinfectious sequelae, trauma, and coagulation phenomena. The authors discuss the effects of the synthetic polymers of basic poly α amino acids, poly l-lysine, and poly l-arginine on blood coagulation, fibrinolysis, bacterial killing, and blood vessels; the properties of natural and synthetic antimicrobial cationic peptides as potential replacements or adjuncts to antibiotics; polycations as opsonizing agents promoting endocytosis/phagocytosis; polycations and muramidases as activators of autolytic wall enzymes in bacteria, causing bacteriolysis and tissue damage; and polycations and nuclear histones as potential virulence factors and as markers of sepsis, septic shock, disseminated intravasclar coagulopathy, acute lung injury, pancreatitis, trauma, and other additional clinical disorders

VL - 10 UR - https://www.dovepress.com/from-amino-acids-polymers-antimicrobial-peptides-and-histones-to-their-peer-reviewed-article-JIR ER - TY - JOUR T1 - Is Histone a Solitary Vile Sepsis-Inducing Agent or Just "a Member of the Gang"? JF - Journal of Infectious Diseases and Therapy Y1 - 2017 A1 - Ginsburg, I. A1 - Koren, E. A1 - Trahtemberg, U. A1 - Van Heerden, V. AB -

 

In this communication we argue that it is improbable that the main cause of death in sepsis is that, upon release

of extracellular traps from neutrophils adhering to endothelial cells, highly cationic toxic histones uniquely cause

endothelial dysregulation, organ failure and death. Activation of neutrophils is always accompanied by a plethora of

pro-inflammatory agents, which may act in synergy with histones to injure cells. Furthermore, many recent articles

have shown a steep rise of circulating histones in many clinical disorders unrelated to sepsis. We argue therefore

that histones do not act as unique alarmins with an outsized role, but are probably another marker of cell damage.

 

VL - 5 UR - https://www.omicsonline.org/open-access/is-histone-a-solitary-vile-sepsisinducing-agent-or-just-a-member-of-thegang-2332-0877-1000329.php?aid=91999 IS - 4 ER - TY - JOUR T1 - Serum histones as biomarkers of the severity of heatstroke in dogs JF - Cell Stress & Chaperones Y1 - 2017 A1 - Yaron Bruchim A1 - Isaac Ginsburg A1 - Segev, Gilad A1 - Ahmad Mreisat A1 - Yochai Avital A1 - Itamar Aroch A1 - Michal Horowitz AB -

Heatstroke is associated with systemic inflammatory response syndrome, leading to multiple organ dysfunction and death. Currently, there is no specific treatment decreasing hyperthermia-induced inflammatory/hemostatic derangements. Emerging studies indicate that histones leaking from damaged cells into the extracellular space are toxic, pro-inflammatory, and pro-thrombotic. We therefore hypothesize that serum histones (sHs) are elevated during heatstroke and are associated with the severity of the disease. Sixteen dogs with heatstroke and seven healthy controls were included in the study. Median serum histones (sHs) upon admission in dogs with heatstroke were significantly higher (P = 0.043) compared to that in seven controls (13.2 vs. 7.3 ng/mL, respectively). sHs level was significantly higher among non-survivors and among dogs with severe hemostatic derangement (P = 0.049, median 21.4 ng/mL vs. median 8.16 ng/mL and P = 0.038, 19.0 vs. 7.0 ng/mL, respectively). There were significant positive correlation between sHs and urea (r = 0.8, P = 0.02); total CO2 (r = 0.661, P = 0.05); CK (r = 0.678, P = 0.04); and prothrombin time (PT) 12 h post presentation (r = 0.888, P = 0.04). The significant positive correlation between sHs and other heatstroke severity biomarkers, and significant increase among severely affected dogs, implies its role in inflammation/oxidation/coagulation during heatstroke. sHs, unlike other prognostic and severity biomarkers in heatstroke, can be pharmacologically manipulated, offering a potential therapeutic target.

VL - Epub ahead of print UR - https://www.ncbi.nlm.nih.gov/pubmed/28643239 ER - TY - JOUR T1 - Characterization of non-dialyzable constituents from cranberry juice that inhibit adhesion, co-aggregation and biofilm formation by oral bacteria JF - Food & Function Y1 - 2017 A1 - Neto, C. C. A1 - Penndorf, K.A. A1 - Feldman, M. A1 - Meron-Sudai, S. A1 - Zakay-Rones, Z. A1 - Steinberg, D. A1 - Fridman, M. A1 - Kashman, Y. A1 - Ginsburg, I. A1 - Ofek, I. A1 - Weiss, E. I. AB -

 

An extract prepared from cranberry juice by dialysis known as nondialyzable material (NDM) has been shown previously to possess anti-adhesion activity toward microbial species including oral bacteria, uropathogenic Escherichia coli and Helicobacter pylori. Bioassay-guided fractionation of cranberry NDM was therefore undertaken to identify the anti-adhesive constituents. An aqueous acetone-soluble fraction (NDMac) obtained from Sephadex LH-20 inhibited adhesion-linked activities by oral bacteria, including co-aggregation of oral bacteria Fusobacterium nucleatum with Streptococcus sanguinis or Porphyromonas gingivalis, and biofilm formation by Streptococcus mutans. Analysis of NDMac and subsequent subfractions by MALDI-TOF MS and 1H NMR revealed the presence of A-type proanthocyanidin oligomers (PACs) of 3–6 degrees of polymerization composed of (epi)catechin units, with some (epi)gallocatechin and anthocyanin units also present, as well as quercetin derivatives. Subfractions containing putative xyloglucans in addition to the mixed polyphenols also inhibit biofilm formation by S. mutans (MIC = 125–250 μg mL−1). These studies suggest that the anti-adhesion activities of cranberry NDM on oral bacteria may arise from a combination of mixed polyphenol and non-polyphenol constituents.

Graphical abstract: Characterization of non-dialyzable constituents from cranberry juice that inhibit adhesion, co-aggregation and biofilm formation by oral bacteria

 

VL - 8 UR - http://pubs.rsc.org/en/content/articlepdf/2017/fo/c7fo00109f IS - 5 ER - TY - JOUR T1 - Thiazolidinedione-8 Alters Symbiotic Relationship in C. albicans-S. mutans Dual Species Biofilm JF - Frontiers in Microbiology Y1 - 2016 A1 - Mark Feldman A1 - Isaac Ginsburg A1 - Abed Al-Quntar1 A1 - Steinberg, Doron AB -

The small molecule, thiazolidinedione-8 (S-8) was shown to impair biofilm formation of various microbial pathogens, including the fungus Candida albicans and Streptococcus mutans. Previously, we have evaluated the specific molecular mode of S-8 action against C. albicans biofilm-associated pathogenicity. In this study we investigated the influence of S-8 on dual species, C. albicans-S. mutans biofilm. We show that in the presence of S-8 a reduction of the co-species biofilm formation occurred with a major effect on C. albicans. Biofilm biomass and exopolysaccharide (EPS) production were significantly reduced by S-8. Moreover, the agent caused oxidative stress associated with a strong induction of reactive oxygen species and hydrogen peroxide uptake inhibition by a mixed biofilm. In addition, S-8 altered symbiotic relationship between these species by a complex mechanism. Streptococcal genes associated with quorum sensing (QS) (comDE and luxS), EPS production (gtfBCD and gbpB), as well as genes related to protection against oxidative stress (nox and sodA) were markedly upregulated by S-8. In contrast, fungal genes related to hyphae formation (hwp1), adhesion (als3), hydrophobicity (csh1), and oxidative stress response (sod1, sod2, and cat1) were downregulated in the presence of S-8. In addition, ywp1 gene associated with yeast form of C. albicans was induced by S-8, which is correlated with appearance of mostly yeast cells in S-8 treated dual species biofilms. We concluded that S-8 disturbs symbiotic balance between C. albicans and S. mutans in dual species biofilm.

VL - 10 UR - http://journal.frontiersin.org/article/10.3389/fmicb.2016.00140/full ER - TY - JOUR T1 - Nuclear histones: major virulence factors or just additional early sepsis markers? A comment JF - Inflammopharmacology Y1 - 2016 A1 - Ginsburg, I. A1 - Koren, E. A1 - Varani, J. A1 - Kohen, R. AB -

In 2009, Xu et al. and Chaput et al. in Nature Medicine had argued that the main cause of death in sepsis is the release from neutrophil nets of nuclear histone, highly toxic to endothelial cells and that these polycations are major and unique virulence factors. Since 2009, numerous researchers have also suggested the involvement of histones in the pathophysiology of many clinical disorders. If histones are indeed major unique virulence toxic agents, then heparin, activated protein C and antibodies to histone should prove excellent antisepsis agents. However, this is provided that these agents are administered to patients early enough before the activation of the cytokine storms, immune responses and the coagulation cascades are irreversibly unleashed. This may not be practical, since a diagnosis of sepsis is usually made much later. Future identifications of novel early markers are therefore needed and a compilation of cocktails of antagonists may replace the faulty single antagonists tried for many years, but in vain, to prevent death in sepsis.

VL - 24 UR - https://www.ncbi.nlm.nih.gov/pubmed/27613722 IS - 5 ER - TY - JOUR T1 - Synergistic Aspects to Explain the Pathophysiology of Sepsis and Septic Shock-An Opinion JF - Journal of Infectious Diseases & Therapy Y1 - 2015 A1 - Erez Koren A1 - Isaac Ginsburg AB -

It is disconcerting and also alarming that today clinicians are still bewildered and helpless when trying to cope with life-threatening sequelae of severe microbial infections, which very often culminate in sepsis, septic shock and death. According to CDC (the Centers for Disease Control and Prevention), the annual incidence of sepsis in the USA affects as many as 750,000 hospitalized patients and mortality rate is about 40% [1,2]. It was found in 2 complementary inpatient cohorts that up to 50% of hospital deaths were linked to sepsis [3]. Worldwide, sepsis is one of the common deadly diseases. It is one of the few conditions to strike with equal ferocity in resource-poor areas and in the developed world. Globally, 20 to 30 million patients are estimated to be afflicted every year. Every hour, about 1,000 people and each day around 24,000 people die from sepsis worldwide and sepsis is one of the least well known diseases. In the developing world, sepsis accounts for 60-80% of lost lives in childhood, with more than 6 million neonates and children affected by sepsis annually. Sepsis is responsible for >100,000 cases of maternal sepsis each year and in some countries is now a greater threat in pregnancy than bleeding or thromboembolism [4,5]. Screening the voluminous literature on sepsis treatment revealed unsuccessful efforts to save patients' lives by administering antibiotics but only a signally-chosen antagonist at a time. The numbers of anti-inflammatory agents tested ineffectively over the years is phenomenal (see below) and today even the most promising activated protein C, the “miracle drug” was recently discontinued [6-9]. The initial reactions to infection are generalized pro-and anti-inflammatory responses. These usually starts by activation by microorganisms and some of their products of neutrophils, macrophages and monocytes, which are followed by toxic effects on vascular endothelial cells via pathogen recognition receptors, leading to endothelial disruption. Why have all the therapeutic strategies tested invariably failed to cope with the sequelae of severe microbial infections and what future approaches might break the stalemate leading to a better understanding of the pathophysiology of the "horror autotoxicus" phenomena of sepsis? [10].

Reviewing the “glorious history” of medical microbiology revealed that immunoglobulins rich in anti-toxins activities proved very effective to cope with those maladies where a single virulence agent, such as the toxin of diphtheria, tetanus and botulism, are the main pathogenetic virulence agents. Also, anti-viral vaccines are the hallmark of the prevention of many childes viral diseases and of viral hepatitis. On the other hand, no single major virulence factor is identified in the majority of Gram positives Gram negatives, fungal and Mycobacterial pathogens. Therefore, it stands to reason that cell and tissue damage inflicted by these microorganisms may be a result of a coordinated "cross-talk" (synergism) among host factors and a multiplicity of pro-inflammatory agents generated during the proliferation of bacteria, mainly in the blood stream. These may include: extracellular pore-forming and membrane-permeabilizing hemolysins, capsular polysaccharides, LPS (endotoxin), the membrane-associated lipoteichoic acid (LTA), the rigid cell-wall peptidoglycan (PPG), leukocyte-derived oxygen and nitrogen species, anti-microbial cationic peptides, phospholipases, cationic proteinases, growth factors, cytokines and chemokines and many others. All these agents might be generated in various stages of inflammation and infection by microbes and by the host response. Furthermore, certain life-saving antibiotics might also act as "double-edged swords" by enhancing the release of microbial products (LPS, LTA, PPG, capsular polysaccharides, intra cellular toxins), resulting from to the activation of nascent autolytic wall enzymes released leading to bacteriolysis [11,12].

VL - 3 UR - http://www.esciencecentral.org/journals/synergistic-aspects-to-explain-the-pathophysiology-of-sepsis-and-septicshockan-opinion-2090-7214-1000254.php?aid=65871 IS - 6 ER - TY - JOUR T1 - Chlorhexidine markedly potentiates the oxidants scavenging abilities of Candida albicans JF - Inflammopharmacology Y1 - 2015 A1 - Isaac Ginsburg A1 - Erez Koren A1 - O. Feuerstein A1 - IP. Zogakis A1 - Miri Shalish A1 - S. Gorelik AB -

The oxidant scavenging ability (OSA) of catalase-rich Candida albicans is markedly enhanced by chlorhexidine digluconate (CHX), polymyxin B, the bile salt ursodeoxycholate and by lysophosphatidylcholine, which all act as detergents facilitating the penetration of oxidants and their intracellular decomposition. Quantifications of the OSA of Candida albicans were measured by a highly sensitive luminol-dependent chemiluminescence assay and by the Thurman's assay, to quantify hydrogen peroxide (H2O2). The OSA enhancing activity by CHX depends to some extent on the media on which candida grew. The OSA of candida treated by CHX was modulated by whole human saliva, red blood cells, lysozyme, cationic peptides and by polyphenols. Concentrations of CHX, which killed over 95 % of Candida albicans cells, did not affect the cells' abilities to scavenge reactive oxygen species (ROS). The OSA of Candida cells treated by CHX is highly refractory to H2O2 (50 mM) but is strongly inhibited by hypochlorous acid, lecithin, trypan blue and by heparin. We speculate that similarly to catalase-rich red blood cells, Candida albicans and additional catalase-rich microbiota may also have the ability to scavenge oxidants and thus can protect catalase-negative anaerobes and facultative anaerobes cariogenic streptococci against peroxide and thus secure their survival in the oral cavity.

VL - 23 UR - http://www.ncbi.nlm.nih.gov/pubmed/26223507 IS - 271 ER - TY - JOUR T1 - Is Bacteriolysis In vivo a Friend or a Foe? Relation to Sepsis, Chronic Granulomatous Inflammation and to Oral Disorders: an Overview Hypothesis JF - SOJ Microbiology & Infectious Diseases Y1 - 2015 A1 - Isaac Ginsburg A1 - Erez Koren A1 - Osnat Feuerstein AB -

tives and their involvement in the pathogenesis of chronic granulomatous inflammation is briefly reviewed. It can be speculated that in humans, leukocytes laden with intracellular bacteria and their non-degraded highly-phlogistic cell-walls may be translocated from inflamed gums (periodontal disease) and from infected dental pulps (pulpitis, periapical granulomas) to remote sites such as damaged heart valves (causing endocarditis) and injured joints (causing chronic arthritis). This phenomenon maybe important, clinically and is in line with the old “Focus of infection theory” from the nineteen twenties, which is no longer considered and discussed in the modern literature.

VL - Articles in Press UR - http://www.symbiosisonlinepublishing.com/microbiology-infectiousdiseases/microbiology-infectiousdiseases29.pdf ER - TY - ICOMM T1 -

The Antioxidant Effect of Fermented Papaya

Preparation in the Oral Cavity

Y1 - 2015 A1 - E. Fibach A1 - Isaac Ginsburg AB -

Oxidative stress has been recognized to play important roles in various diseases, including of the oral cavity. However, nutritional supplementation of antioxidants to ameliorate the consequences of oxidative stress is debatable. One caveat is that oxidative status is often measured under non-physiological conditions. Here, we investigated the antioxidant potential of fermented papaya preparation (FPP), a product of yeast fermentation of Carica papaya Linn, under conditions that prevail in the oral cavity. Employing highly sensitive luminol-dependent chemiluminescence assays, we show that its antioxidant capacity was augmented by saliva (up to 20-fold, p<0.0001, at 10mg) and its components (mucin, albumin) as well as by red blood cells (RBC) and microorganisms present in the normal and pathological environment of the oral cavity. Polyphenols are major plant antioxidants. Using the Folin–Ciocalteu’s assay, a very low amount of phenols was measured in FPP suspended in a salt solution. However, its suspension in saliva, albumin, mucin or RBC produced up to sixfold increase, p<0.001, compared with the sum of polyphenols assayed separately. The results suggested that these enhancing effects were due to the solubilization of antioxidant polyphenols in FPP by saliva proteins and the binding to RBC and microorganisms, thus increasing their availability and activity. Copyright © 2015 John Wiley & Sons, Ltd.

JF - PHYTOTHERAPY RESEARCH UR - http://www.ncbi.nlm.nih.gov/pubmed/26031772 ER - TY - JOUR T1 -

Unrealistic nonphysiological amounts of reagents and a disregard for published literature

JF - mBio - American Society for Microbiology Y1 - 2015 A1 - Isaac Ginsburg AB -

LETTER Here are some comments and useful suggestions after reading an article in mBio by Brown et al. entitled “Mechanisms underlying the exquisite sensitivity of Candida albicans to combinatorial cationic and oxidative stress that enhances the potent fungicidal activity of phagocytes” (1). In this paper, we are informed that a simultaneous exposure to 5 mM H2O2 and to cationic NaCl at 1 M is much more potent than the individual stresses themselves and that this combinatorial stress kills C. albicans synergistically in vitro. Such combinations are obviously absolutely unrealistic and not physiological. As a comparison I wonder why the authors had not also tested naturally occurring antimicrobial cationic peptides such as LL37 found in large amounts in neutrophil granules? Had the authors read the classical papers describing the possible mechanisms of bactericidal effects of neutrophils, they would have realized that there is actually no free-floating H2O2 in phagosomes following phagocytosis. This is because activation of NADPH-oxidase yields superoxide, which very rapidly interacts with myeloperoxidase (MPO) and with a halide (Cl−) to generate microbicidal amounts of hypochlorous acid (HOCl) (2–5)! Therefore, HOCl should have definitely been considered and tested in the system described by the authors. Also, the term flux used may be inappropriate since, in their study, both H2O2 and NaCl were actually applied as a bolus. Fluxes of oxidants are generated mainly by activated neutrophils and macrophages and by xanthine and xanthine oxidase in endothelial cells (2) Also, I wonder whether Na used is specific and whether potassium ions can also have the same effects in their system? The authors also claimed that catalase-derived peroxide detoxification, which is inhibited by cations, leads to intracellular ROS accumulation because catalase activity had been affected. If so, why had the catalase inhibitor azide or aminotriazole not been tested? In their study, the authors grew Candida cells in Tris-buffered yeast extract-peptone-dextrose medium (YPDT; pH 7.4). However, the authors have not cited key papers showing that D-glucose, in media on which candida grow, may also suppress catalase formation (6, 7). Using unrealistic, nonphysiological amounts of reagents will not increase our understanding of how biological processes really occur in vivo, despite the need to employ in vitro models. Also, disregarding key published data on neutrophil functions and Candida biology is unacceptable. Can this be a “menace to the future of honest science” (8) and also a “transgression” (9)? See also a recent publication by Casadevall and Fang (10).

VL - 6 UR - http://www.ncbi.nlm.nih.gov/pubmed/25900656 IS - 2 ER - TY - JOUR T1 -

Intravesical administration of green tea extract attenuates the inflammatory response of bacterial cystitis--a rat model

JF - BJU international Y1 - 2014 A1 - S. Rosenberg A1 - R. Horowitz A1 - S. Coppenhagen-Glazer A1 - G. Pizov A1 - A. Elia A1 - ON. Gofrit A1 - Isaac Ginsburg A1 - D. Pode AB - OBJECTIVE: To explore the effect of intravesical instillation of green tea extract (GTE) on a rat model of bacterial cystitis. MATERIALS AND METHODS: In vitro bactericidal properties of GTE were analysed by adding GTE to a suspension of uropathogenic E. coli (UPEC), streaking on MacConkey agar, and incubating overnight. In vivo effects of intravesical instillation of GTE on bacterial cystitis was analysed using a rat model of bacterial cystitis. In all, 42 female Sabra rats weighing 200-260 g were divided into five groups. Parameters measured were bladder weight (percentage of the total rat weight), dipstick urine analysis and histopathological changes in the bladder. Histological changes evaluated were degree of oedema, mixed inflammatory infiltration, urothelial epithelial invasion by neutrophils and reactive atypia. RESULTS: No in vitro bactericidal activity was detected for GTE. Intravesical instillation of GTE did not cause damage to the rat bladders. Intravesical instillation of GTE attenuated the inflammatory response to UPEC-SR71-induced bacterial cystitis in this rat model. CONCLUSIONS: Intravesical instillation of GTE attenuated the inflammatory response to UPEC-SR71-induced bacterial cystitis and is a novel approach to the treatment of bacterial cystitis. High concentrations of intravesical GTE did not cause histologically evident damage to the rat bladder. The results of this study are preliminary and further studies will be needed to explore the feasibility of using this approach in humans. VL - 114 IS - 4 ER - TY - JOUR T1 -

LL-37 opsonizes and inhibits biofilm formation of Aggregatibacter actinomycetemcomitans at subbactericidal concentrations

JF - INFECTION AND IMMUNITY (IAI) Y1 - 2013 A1 - A. Sol A1 - O. Ginesin A1 - S. Chaushu A1 - L. Karra A1 - S. Coppenhagen-Glazer A1 - Isaac Ginsburg A1 - G. Bachrach AB - Host defense peptides are immediate responders of the innate immunity that express antimicrobial, immunoregulatory, and wound-healing activities. Neutrophils are a major source for oral host defense peptides, and phagocytosis by neutrophils is a major mechanism for bacterial clearance in the gingival tissue. Dysfunction of or reduction in the numbers of neutrophils or deficiency in the LL-37 host defense peptide was each previously linked with proliferation of oral Aggregatibacter actinomycetemcomitans which resulted in an aggressive periodontal disease. Surprisingly, A. actinomycetemcomitans shows resistance to high concentrations of LL-37. In this study, we demonstrated that submicrocidal concentrations of LL-37 inhibit biofilm formation by A. actinomycetemcomitans and act as opsonins and agglutinins that greatly enhance its clearance by neutrophils and macrophages. Improved uptake of A. actinomycetemcomitans by neutrophils was mediated by their opsonization with LL-37. Enhanced phagocytosis and killing of A. actinomycetemcomitans by murine macrophage-like RAW 264.7 cells were dependent on their preagglutination by LL-37. Although A. actinomycetemcomitans is resistant to the bactericidal effect of LL-37, our results offer a rationale for the epidemiological association between LL-37 deficiency and the expansion of oral A. actinomycetemcomitans and indicate a possible therapeutic use of cationic peptides for host defense VL - 81 IS - 10 ER - TY - JOUR T1 -

The oxidant scavenging capacity of the oral Mycoplasma salivarium

JF - Archives of Oral Biology Y1 - 2013 A1 - JD Kornspan A1 - Isaac Ginsburg A1 - S Rottem AB - OBJECTIVE: Mycoplasma salivarium is a human oral potential pathogen that preferentially resides in dental plaques and gingival sulci. It has been suggested that this organism may play an etiological role in inflammatory processes in the oral cavity. The aim of this work was to determine whether M. salivarium possesses a potent oxidant scavenging capacity (OSC). DESIGN: The OSC of M. salivarium was quantified by a highly sensitive luminal-dependent chemiluminescence assay in the presence of cocktails that induced a constant flux of luminescence resulting from the generation of peroxide, hydroxyl radical (cocktail A) and NO, superoxide and peroxynitrites (cocktail B). RESULTS: M. salivarium markedly reduced oxidative stress by scavenging both free reactive oxygen and nitrogen species. The OSC of M. salivarium was much higher than that of other Mycoplasma species. Most of M. salivarium OSC was confined to the cytosolic fraction and was markedly increased in the presence of tannic acid, red blood cells or mucin. The cytosolic OSC of M. salivarium was heat stable and not affected by sodium azide or prolonged proteolysis. However, it was markedly decreased upon dialysis, suggesting that the major reducing activity is not enzymatic but rather, a low molecular weight compound(s). CONCLUSIONS: The ability of M. salivarium to scavenge oxidants may play a role in the survival and pathogenicity of this microorganism. The enhanced OSC of M. salivarium in the presence of tannic acid, red blood cells or mucin might have a significant importance to assess complex interactions with polyphenols from nutrients, salivary proteins and red blood cells extravasated from injured capillaries during infection and inflammation in oral tissues. VL - 58 IS - 10 ER - TY - JOUR T1 -

Saliva: a ‘solubilizer’ of lipophilic antioxidant polyphenols

JF - Oral Diseases Y1 - 2013 A1 - Isaac Ginsburg A1 - Ron Kohen A1 - Erez Koren AB - Saliva has become a central topic of research in many scientific categories. It is involved in mastication, lubrication, buffering action, maintenance of tooth integrity, physicochemical and antimicrobial defense, immunization, wound healing, taste, and early digestion (Amerongen and Veerman, 2002; Fábián et al, 2008). It is also important in biofilm formation on tooth surfaces, bacterial adhesion, serves as an important source for genetic and forensic profiles and maintains mucosal integrity of the oral and upper gastrointestinal mucosal surfaces. The oral cavity can be considered a ‘bio-reactor’ (Gorelik et al, 2008; Kanner et al, 2012) where, on a daily basis, multiple interactions occur among salivary electrolytes, thousands of different proteins including the glycoprotein mucin, plasma-derived albumin, immunoglobulins, digestive enzymes such as alpha amylase as well as with substantial amounts of polyphenols from nutrients. However, saliva also contains potentially toxic H2O2 generated by oral streptococci, salivary lactoperoxidase generates bactericidal and cytocidal thiocyanate anion (SCN−) and activated phagocytes release a series of toxic oxidants (Grisham and Ryan, 1990; Nagler et al, 2002; Halliwell and Gutteridge, 2007). This implies that saliva and the oral structures may be constantly exposed to oxidative stresses. Over the evolution, saliva has evolved the protective low molecular weight antioxidants (LMWA) uric acid, ascorbate, reduced glutathione, and plasma albumin possessing antioxidant activity, is delivered to saliva via the crevicular fluid (Sculley and Langley-Evans, 2002; Liskmann et al, 2007; Ginsburg et al, 2012). However, saliva may also contain red blood cells extravasated either following tooth brushing, use of tooth picks, during orthodontic treatment or in oral pathologies. Erythrocytes had been proposed to serve not only as transporters of oxygen and removers of CO2 but also as ‘sinks’ for reactive oxygen species (ROS) and as protectors of other cells against oxidant toxicity (Richards et al, 1998; Koren et al, 2009, 2010; Ginsburg et al, 2012). It was also proposed that quantifications of antioxidants be performed in whole blood but not exclusively in plasma (Ginsburg et al, 2011b). Today, the main justification to present a ‘letter to the editor’ on salivary functions, stems from a series of recent novel observations, which shed a new insight on the interactions of salivary proteins with polyphenols from nutrients and with blood cells and how such interactions might affect the redox status and the integrity of the oral cavity. The following are the main highlights: Microbial and red blood cells acquired enhanced oxidant-scavenging abilities (OSA) by avidly binding to their surfaces a large assortment of antioxidant polyphenols from nutrients. Such complexes acted in synergy with the antioxidants in whole unstimulated saliva to decompose ROS (Koren et al, 2009, 2010; Ginsburg et al, 2011a). Many of the polyphenols in aqueous beverages (e.g. red wine, tea, coffee, cocoa, cinnamon, cranberries, pomegranate etc.) might not exist in a full soluble state, and therefore not available as effective antioxidants. However, this shortcoming could be overcome by simply mixing the various agents either with fresh un-stimulated saliva (Ginsburg et al, 2012) or with mucin and albumin, which all serve as ‘solubilizers’ of lipophilic agents to render polyphenols more available as efficient antioxidants. Polyphenols in plants and fruit beverages can strongly adhere to the huge surface area of the oral cavity are retained there for long periods and this, despite a normal salivary flow. This suggested that bound polyphenols could act as a ‘slow release apparatus’ helping to maintain a proper redox status and probably also the defense against oxidative stresses (Ginsburg et al, 2012). The OSA in the oral cavity is a sum result of the synergistic interactions among antioxidants in saliva, crevicular fluid, antioxidant polyphenols from nutrients, blood elements, and paradoxically perhaps, also the indigenous catalase-positive colonizing microbial flora (Ginsburg et al, 2011b). Figure 1 represents one example, of many studied, showing a synergistic OSA resulting from the interactions among saliva, whole blood and the tea major polyphenol epigallocatechin gallate (EGCG). However, one has also to take into consideration that the presence in the oral cavity of excessive amounts of heme proteins which occur in periodontal pathologies, may also act as a ‘double-edged sword’ by supplying excessive amounts of Fe+2, instrumental in the generation, via the Fenton reaction, of the highly toxic hydroxyl radical. Antioxidant polyphenols might under certain conditions, also act as pro-oxidants and as signaling molecules which can generate pro-inflammatory agents (Rahman et al, 2006; Halliwell and Gutteridge, 2007; Halliwell, 2008). Figure 1. Luminol-dependent chemiluminescence patterns (Ginsburg et al, 2004) induced by combinations among unstimulated fasting saliva, whole blood, and epigallocatechin gallate (EGCG). The various agents and combinations among them were added to test tubes containing 800 μl of Hanks balanced salt solution (HBSS). This was followed by the addition of a ‘cocktail’ comprised of luminol (10 μM), sodium selenite (1 mM), H2O2 (1 mM) and CoCl2.6H2O (10 μM) which induced a rapid light wave due to H2O2 and hydroxyl radical. Note that sub inhibitory amounts of saliva and of EGCG acted in synergy with whole blood to significantly quench luminescence (n = 5) Because of the very low bioavailability of polyphenols resulting from intensive metabolism in the liver and by the microbial flora of the gastrointestinal tract and due to a strict regulatory mechanism (Ginsburg et al, 2011b) only micromolar amounts of antioxidant polyphenols capable of protecting LDL from oxidation, eventually manage to reach plasma. It was therefore recently proposed that polyphenols from nutrients exert their beneficial effect as antioxidants mainly in the oral cavity and in the stomach (Gorelik et al, 2008; Kanner et al, 2012) but to a much lesser extent in plasma. Accordingly, polyphenols in red wine, coffee, tea, and in other beverages which undergo solubilization by salivary proteins, may now neutralize advanced lipid oxidation end-products generated in the stomach during the metabolism of fatty acids (Gorelik et al, 2008; Kanner et al, 2012) and thus able to prevent the oxidation of LDL in the circulation. It was therefore proposed that consumption of fatty foods be always accompanied by a simultaneous consumption of fruit beverages rich in antioxidant polyphenols. Further research is however needed to assess the role of salivary antioxidants, polyphenols from nutrients, blood elements, and those antioxidants associated with microbial flora as potential players in the homeostasis and in the complex milieu of the oral cavity in health and in disease states. VL - 19 IS - 3 ER - TY - JOUR T1 -

The oxidant-scavenging abilities in the oral cavity may be regulated by a collaboration among antioxidants in saliva, microorganisms, blood cells and polyphenols: A Chemiluminescence - based study.

 

JF - PLoS ONE Y1 - 2013 A1 - Isaac Ginsburg A1 - Ron Kohen A1 - Erez Koren A1 - Miri Shalish A1 - David Varon A1 - Ella Shai AB - Saliva has become a central research issue in oral physiology and pathology. Over the evolution, the oral cavity has evolved the antioxidants uric acid, ascorbate reduced glutathione, plasma-derived albumin and antioxidants polyphenols from nutrients that are delivered to the oral cavity. However, blood cells extravasated from injured capillaries in gingival pathologies, or following tooth brushing and use of tooth picks, may attenuate the toxic activities of H2O2 generated by oral streptococci and by oxidants generated by activated phagocytes. Employing a highly sensitive luminol-dependent chemiluminescence, the DPPH radical and XTT assays to quantify oxidant-scavenging abilities (OSA), we show that saliva can strongly decompose both oxygen and nitrogen species. However, lipophilic antioxidant polyphenols in plants, which are poorly soluble in water and therefore not fully available as effective antioxidants, can nevertheless be solubilized either by small amounts of ethanol, whole saliva or also by salivary albumin and mucin. Plant-derived polyphenols can also act in collaboration with whole saliva, human red blood cells, platelets, and also with catalase-positive microorganisms to decompose reactive oxygen species (ROS). Furthermore, polyphenols from nutrient can avidly adhere to mucosal surfaces, are retained there for long periods and may function as a “slow- release devises” capable of affecting the redox status in the oral cavity. The OSA of saliva is due to the sum result of low molecular weight antioxidants, albumin, polyphenols from nutrients, blood elements and microbial antioxidants. Taken together, saliva and its antioxidants are considered regulators of the redox status in the oral cavity under physiological and pathological conditions. VL - 8 IS - 5 ER - TY - JOUR T1 -

Triphala (PADMA) extract alleviates bronchial hyperreactivity in a mouse model through liver and spleen immune modulation and increased anti-oxidative effects

JF - Therapeutic Advances in Respiratory Disease Y1 - 2012 A1 - Horani, Amjad A1 - Shoseyov, David A1 - Isaac Ginsburg A1 - Rufayda Mruwat A1 - Sarit Doron A1 - Johnny Amer A1 - Rifaat Safadi AB - Objectives: Triphala (TRP), a herbal extract from Tibetan medicine, has been shown to affect lymphocytes and natural killer T (NKT) cell function. We hypothesize that TRP could ameliorate bronchial hyperreactivity through immune-cell modulations. Methods: Asthma mouse models were generated through intraperitoneal (IP) injections of ovalbumin (OVA)/2 weeks followed by repeated intranasal OVA challenges. Mice were then treated with normal saline (OVA/NS) or Triphala (OVA/TRP). Data were compared with mice treated with inhaled budesonide. All groups were assessed for allergen-induced hyperreactivity; lymphocytes from lungs, livers and spleens were analyzed for OVA-induced proliferation and their alterations were determined by flow cytometry. Oxidative reactivity using chemiluminescence, serum anti-OVA antibodies level and lung histology were assessed. Results: Both TRP and budesonide significantly ameliorated functional and histological OVA-induced bronchial hyperreactivity. TRP had no effect on serum anti-OVA antibodies as compared with decreased levels following budesonide treatment. Furthermore, a significant increase in lung and spleen CD4 counts and a decrease in the liver were noted after TRP treatments. Bronchoalveolar fluid from TRP-treated animals but not from the budesonide-treated animals showed anti-oxidative effects. Conclusion: TRP and budesonide caused a significant decrease in bronchial reactivity. TRP treatment altered immune-cell distributions and showed anti-oxidative properties. These findings suggest that immune-cell modulation with TRP can ameliorate lung injury. VL - 6 ER - TY - JOUR T1 -

Saliva increases the availability of lipophilic polyphenols as antioxidants and enhances their retention in the oral cavity

JF - Archives of Oral Biology Y1 - 2012 A1 - Isaac Ginsburg A1 - Erez Koren A1 - M. Shalish A1 - J. Kanner A1 - Ron Kohen AB - OBJECTIVE: Lipophilic polyphenols in fruit beverages can avidly bind to surfaces of microorganisms and to blood cells and to impart upon them enhanced oxidant scavenging abilities (OSA). However, since many of the polyphenols are actually not fully soluble in water, they are therefore not available to act as effective antioxidant agents. We hypothesized that whole saliva, proteins such as albumin and mucin, human red blood cells and platelets, may all increase the "solubility" and availability of lipophilic antioxidant polyphenols thus increasing the OSA of whole saliva. DESIGN: The OSA of whole un-stimulated human saliva, obtained from healthy donors and of combinations among saliva, mucin, blood cells, fruit beverages and reagent polyphenols were quantified by chemiluminescence, DPPH radical and tetrazolium reduction assays. Kinetics of the clearance of polyphenols from saliva after holding in the mouth for 30s of an extract from beverages cinnamon was assayed by the Folin Ciocalteu's and the luminescence assays. RESULTS: OSA of fruit beverages and of reagent polyphenols were markedly increased by whole saliva, mucin and by red blood cells. Polyphenols associated with a cinnamon extract were retained in the oral cavity for several hours as measured by luminescence and Folin reagent techniques. CONCLUSIONS: A new approach to explain the additional role of saliva and salivary proteins and of blood cells as enhancers of OSA of lipophilic polyphenols is presented. This might have a significant importance to assess complex interactions among polyphenols from nutrients, salivary antioxidants, salivary proteins and blood cells extravasated from injure capillaries during infection and inflammation. VL - 57 IS - 10 ER - TY - JOUR T1 -

Carbamate derivatives of indolines as cholinesterase inhibitors and antioxidants for the treatment of Alzheimer's disease.

JF - Journal of Medicinal Chemistry Y1 - 2012 A1 - I Yanovsky A1 - E Finkin-Groner A1 - A Zaikin A1 - L Lerman A1 - H Shalom A1 - S Zeeli A1 - T Weill A1 - Isaac Ginsburg A1 - A Nudelman A1 - M Weinstock AB - The cascade of events that occurs in Alzheimer's disease involving oxidative stress and the reduction in cholinergic transmission can be better addressed by multifunctional drugs than cholinesterase inhibitors alone. For this purpose, we prepared a large number of derivatives of indoline-3-propionic acids and esters. They showed scavenging activity against different radicals in solution and significant protection against cytotoxicity in cardiomyocytes and primary cultures of neuronal cells exposed to H2O2 species and serum deprivation at concentrations ranging from 1 nM to 10 μM depending on the compound. For most of the indoline-3-propionic acid derivatives, introduction of N-methyl-N-ethyl or N-methyl-N-(4-methoxyphenyl) carbamate moieties at positions 4, 6, or 7 conferred both acetyl (AChE) and butyryl (BuChE) cholinesterase inhibitory activities at similar concentrations to those that showed antioxidant activity. The most potent AChE inhibitors were 120 (3-(2-aminoethyl) indolin-4-yl ethyl(methyl)carbamate dihydrochloride) and 94 (3-(3-methoxy-3-oxopropyl)-4-(((4-methoxyphenyl)(methyl) carbamoyl)oxy)indolin-1-ium hydrochloride) with IC50s of 0.4 and 1.2 μM, respectively. VL - 55 IS - 23 ER - TY - JOUR T1 -

Herbal flavonoids inhibit the development of autoimmune diabetes in NOD mice: proposed mechanisms of action in the example of PADMA 28

JF - Alternative Medicine Studies Y1 - 2011 A1 - Lola Weiss A1 - Vivian Barak A1 - Itamar Raz A1 - N. Kaiser A1 - Reuven Or A1 - Shimon Slavin A1 - Isaac Ginsburg AB - Padma 28 is a multicompound herbal preparation based on the camphor formulas from traditional tibetan medicine (TTM). It contains a variety of different secondary plant substances, which include terpenes and polyphenols such as flavonoids and tannins. The formula is used in various chronic inflammatory diseases. The aim of this study was to investigate whether secondary plant substances as present in Padma 28 are able to prevent the development of autoimmune diabetes. Female NOD mice were administered an aqueous Padma 28 extract intraperitonneally (i.p.), subcutaneously (s.c.) or per os (p.o.) over a period of 13 weeks. The development of autoimmune diabetes mellitus type 1 was monitored over 24 weeks. Untreated and saline treated mice served as controls. After 24 weeks, 20% of the control groups were free of diabetes while 100% and 80% of the animals administered aqueous extracts from Padma 28 i.p. or s.c., respectively, were diabetes-free. In the p.o. group, 33% were diabetes-free. In controls, only a few pancreatic islets had survived. Animals treated i.p. with Padma 28 had preserved islets with minimal lymphocyte infiltrations. Spleen cells from animals treated i.p. or s.c. with Padma 28 and stimulated with concanavalin A showed significant elevations in the levels of interleukins (IL)-10, IL-6 and IL-4. In the plasma, the level of the Th1 cytokine IL-12 was decreased in the i.p. group. Padma 28 treatment by the i.p. route of administration showed a significant decrease in CD8 cytotoxic cells, which have been implicated in the destruction of the islets. The findings support the use of secondary plant substances such as flavonoids in inflammatory autoimmune diseases. The results suggest that Padma 28 has immuno­modulatory effects associated with a shift from Th1 to Th2 immune response and may have protective effects against autoimmune diabetes. VL - 1 IS - 1 ER - TY - JOUR T1 -

Visible light promotes interleukin-10 secretion by sublethal fluences

JF - Photomedicine and Laser Surgery Y1 - 2011 A1 - O. Feuerstein A1 - R. Assad A1 - E. Koren A1 - Isaac Ginsburg A1 - E.I. Weiss A1 - Y. Houri-Haddad AB - OBJECTIVE: To determine the effect of blue light on cultured splenocyte viability and secretion of cytokines involved in the regulation of immune responses in the inflammatory process. BACKGROUND DATA: Previous studies showed that red light has various effects on lymphocyte proliferation and production of cytokines. MATERIALS AND METHODS: Cultured mouse splenocytes were exposed to visible light (wavelengths, 450-490 nm) using 2-108 J/cm(2), with and without scavengers of reactive oxygen species (ROS). One half of the samples were stimulated by the heat-killed periopathogenic bacterium Porphyromonas gingivalis. Following incubation for 48 h, the levels of the cytokines interleukin-10 (IL-10), tumor necrosis factor alpha (TNFα), and interferon gamma (IFNγ) were analyzed, and the viability of the cells was tested using the XTT assay. The total oxidant-scavenging capacity of the nonexposed and exposed splenocytes to light was determined by a chemiluminescence assay, and the temperature of the cell culture medium was measured after light exposure. RESULTS: Exposure to blue light at fluences of 27-108 J/cm(2) caused a decrease in splenocyte viability. Lower fluences increased the secretion of cytokine IL-10, which was abolished by ROS scavengers. Exposure to light had no effect on the secretion of cytokines TNFα and IFNγ. Following exposure to light, more ROS were detected and the temperature measured did not exceed 30.7°C. CONCLUSIONS: Blue light had a stimulatory effect on cell secretion of IL-10, mediated by ROS. Therefore, an increase in IL-10 might be a potential method for modulating the inflammatory processes of local disorders, such as periodontitis and arthritis. VL - 29 IS - 9 ER - TY - JOUR T1 -

The herbal preparation Padma® 28 protects against neurotoxicity in PC12 cells

JF - PHYTOTHERAPY RESEARCH Y1 - 2011 A1 - Isaac Ginsburg A1 - L Rozenstein-Tsalkovich A1 - Erez Koren A1 - H Rosenmann AB - Padma® 28 is a multicompound herbal preparation based on the camphor formulas from traditional Tibetan medicine (TTM). It contains a variety of different secondary plant substances, which include terpenes and polyphenols such as flavonoids and tannins. As a rich source of antioxidant polyphenols, this herbal Padma 28 preparation seems to be a promising candidate for the treatment of degenerative diseases such as Alzheimer's disease (AD), a condition involving oxidative stress. Moreover, polyphenols have also been shown to mitigate AD neuropathology. The study investigated the protective effect of Padma 28 and of certain polyphenols on the neurotoxicity of PC12 cells induced by the neurotoxins: amyloid-beta (Aβ), glutamate, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 3-nitropropionate (3-NP), known to be involved in AD, Parkinson's disease (PD), amyotrophic-lateral-sclerosis (ALS) and Huntington's disease (HD), respectively. The decrease in cell viability induced by each of the toxins was significantly attenuated by Padma 28 treatment. Also, a decrease in the oxidative capacity of PC12 cells treated with Padma 28 was noted, indicating that the decrease in cell viability induced by the toxins might have been the result of an oxidative stress which could be attenuated by Padma 28 acting as a potent antioxidant. Padma 28, which is available in Europe and USA, seems to be a promising candidate for the treatment of CNS diseases. VL - 25 IS - 5 ER - TY - JOUR T1 -

Quantifying Oxidant-Scavenging Ability of Blood

JF - The New England Journal of Medicine Y1 - 2011 A1 - Isaac Ginsburg A1 - Ron Kohen A1 - Erez Koren AB - Screening the voluminous literature describing the quantifications of antioxidant levels in patients with various clinical disorders and after the administration of supplements has revealed that nearly all the studies have exclusively involved measurements in plasma. Since the classic tests have mainly quantified levels of low-molecular- weight antioxidants and albumin in human plasma but not those associated with erythrocyte enzymes and hemoglobin, such studies have not taken into account the roles of circulating cells, all laden with catalase and additional enzymes. This finding raises serious doubt as to whether reports on antioxidant quantifications exclusively in plasma can be trusted to represent true oxidant-scavenging abilities. Using a new chemiluminescence assay and an assay involving the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) (which are adapted to quantify antioxidants in whole blood),1 we have shown that erythrocytes, platelets, and lymphocytes not only rapidly scavenge reactive oxygen species but also avidly bind to their surfaces a large variety of antioxidant polyphenols, which further enhance their oxidantscavenging abilities.2,3 Such complexes could further act synergistically with low-molecular-weight antioxidants in plasma and with albumin to decompose reactive oxygen species. The synergistic scavenging effect of reactive oxygen species can be induced by a combination of human erythrocytes, plasma, and the representative polyphenol, epicatechin (Fig. 1). The advantage of the luminescence assay over the other classic methods is that it can quantify antioxidants in whole blood and that only 2 to 3 mm3 are needed to rapidly assess its oxidantscavenging ability. As proposed by Richards et al.4 and by Minetti and Malorni,5 erythrocytes have potent antioxidant properties that can act as sinks and as protectors against reactive oxygen species but may also act as pro-oxidant cells. It has been suggested that the genuine oxidant-scavenging ability of blood is most probably a result of the synergistic effects exerted by the antioxidants associated with blood cells, mostly due to catalase, superoxide dismutase, glutathione peroxidase, oxidoreductase, and hemoglobin, cells that are coated in an accumulative manner by dietary polyphenols, free circulating polyphenols, and low-molecular-weight antioxidants and albumin in plasma.2,3 The ability of blood cells to bind antioxidant polyphenols may be an important phenomenon with far-reaching in vivo consequences. With all these factors taken together, it is paramount that antioxidants be measured in whole blood and not in plasma alone in clinical settings. VL - 364 IS - 9 ER - TY - JOUR T1 -

Microbial and host cells acquire enhanced oxidant-scavenging abilities

by binding polyphenols

JF - Archives of Biochemistry and Biophysics Y1 - 2011 A1 - Isaac Ginsburg A1 - Ron Kohen A1 - Erez Koren AB - The dilemma whether supplementations of dietary antioxidants might prevent the adverse consequences of oxidative stress, the inadequacy of the analytical methods employed to quantify oxidant scavenging ability (OSA) levels in whole blood and the distribution and fate of polyphenols and their metabolites in various body compartments following oral consumption are discussed. While none-metabolized polyphenols might exert their antioxidant effects mainly in the oral cavity, metabolized polyphenols might be beneficial in the gastrointestinal tract to counteract the toxicity of oxidants and also of the sequelae of inflammatory processes. Although only micromolar amounts of polyphenols and their metabolites eventually reach the blood circulation, these may nevertheless still be highly effective as scavengers of reactive oxygen and nitrogen species because of their ability to synergize with plasma low molecular-weight antioxidants and with albumin. Polyphenols can avidly bind to surfaces of microorganisms and of blood cells to markedly enhance their OSA, therefore the routine quantifications of antioxidant levels conducted in clinical settings should always use catalase-rich whole blood but not as customary, plasma alone. In addition to their antioxidant and metal chelating properties, polyphenols may also act as signaling agents capable of affecting metabolic, inflammatory, autoimmune, carcinogenic and aging processes. VL - 506 IS - 1 ER - TY - JOUR T1 -

Polyphenols enhance total oxidant-scavenging capacities of human blood by binding to red blood cells

JF - Experimental Biology and Medicine Y1 - 2010 A1 - Erez Koren A1 - Ron Kohen A1 - Isaac Ginsburg AB - The present study offers a new look at the role of erythrocytes and of erythrocytes-polyphenol complexes as potent 'sinks' for reactive oxygen species. We hereby show that human erythrocytes have the capacity not only to carry oxygen, but also to bind avidly to their surfaces a large variety of polyphenol antioxidants, which endows upon such complexes enhanced total oxidant-scavenging capacities (TOSC). This was proven by using confocal microscopy, 2,2-diphenyl-1-picrylhydrazyl radical, Folin-Ciocalteu's reagent, cyclic voltammetry and chemiluminescence techniques. The results presented suggest that the true TOSC of blood is the sum of intracellular antioxidants of red blood cells and other blood cells (mainly due to catalase), the polyphenols bound to their surfaces and the antioxidant agents present in plasma. Since erythrocytes can avidly bind and rapidly remove circulating polyphenols, the rule of the thumb to quantify antioxidants in health and disease processes exclusively in plasma as customary in clinical settings, does not represent the true TOSC of whole blood. We also postulate that circulating erythrocytes and possibly also other blood cells might be constantly coated by polyphenols from supplemented nutrients, which act as antioxidant depots and can thus act as protectors against the harmful consequences of oxidative stress. Further studies are needed to determine the faith of polyphenols in the circulation and their sequestration in the spleen. VL - 235 IS - 6 ER - TY - JOUR T1 -

A multi-component herbal preparation (PADMA 28) improves structure/function of corticosteroid-treated skin, leading to improved wound healing of subsequently induced abrasion wounds in rats

JF - Archives of Dermatological Research Y1 - 2010 A1 - MN Aslam A1 - RL Warner A1 - N Bhagavathula A1 - Isaac Ginsburg A1 - James Varani AB - PADMA 28 is a multi-component herbal mixture formulated according to an ancient Tibetan recipe. PADMA 28 is known to stimulate collagen production and reduced levels of collagen-degrading matrix metalloproteinases (MMPs). The goal of the present study was to determine whether topical treatment of rat skin with PADMA 28 would improve skin structure/function, and whether subsequently induced abrasion wounds would heal more rapidly in skin that had been pretreated with PADMA 28. Hairless rats were exposed to a potent topical corticosteroid (Temovate) in combination with either DMSO alone or with PADMA 28 given topically. At the end of the treatment period, superficial wounds were created in the skin, and time to wound closure was assessed. Collagen production and matrix-degrading MMPs were assessed. Abrasion wounds in skin that had been pretreated with PADMA 28 healed more rapidly than did wounds in Temovate plus DMSO-treated skin. Under conditions in which improved wound healing was observed, there was an increased collagen production and decreased MMP expression, but no significant epidermal hyperplasia and no evidence of skin irritation. The ability to stimulate collagen production and inhibit collagen-degrading enzymes in skin and facilitate more rapid wound closure without irritation should provide a rationale for development of the herbal preparation as a "skin-repair" agent. VL - 302 IS - 9 ER - TY - JOUR T1 -

Total oxidant-scavenging capacities of plasma from glycogen storage disease type Ia patients as measured by cyclic voltammetry, FRAP and luminescence techniques

JF - Journal of Inherited Metabolic Disease Y1 - 2009 A1 - Erez Koren A1 - J. Lipkin A1 - A. Klar A1 - E. Hershkovitz A1 - Isaac Ginsburg A1 - Ron Kohen AB - It has been suggested that the very low incidence of atherosclerosis in glycogen storage disease type Ia (GSD Ia) subjects might be attributed to elevated levels of uric acid, one of the potent low molecular- weight antioxidants found in plasma. The present communication describes a use of two analytical methods-cyclic voltammetry and ferric reducing ability of plasma-and also two chemiluminescence methods to evaluate the total oxidant-scavenging capacities (TOSC) of plasma from GSD Ia patients. Our results verified the elevation of TOSC in GSD Ia patients and we propose the inclusion of luminescence and cyclic voltammetry assays as reliable methods for estimating TOSC in a variety of clinical disorders. Our findings with the cyclic voltammetry method add support to the assumption that the elevated uric acid levels might be the main contributor to plasma antioxidant capacity and possible protection against atherosclerosis. VL - 32 IS - 5 ER - TY - JOUR T1 -

Amelioration of hepatic fibrosis via Padma Hepaten is associated with altered natural killer T lymphocytes

JF - Clinical & Experimental Immunology Y1 - 2009 A1 - Isaac Ginsburg A1 - Erez Koren A1 - A. Horani A1 - M. Mahamid A1 - S. Doron A1 - N. Muhanna A1 - J. Amer A1 - R. Safadi AB - Hepatic fibrosis is the end-stage consequence of chronic liver disease, affecting many people worldwide. Unlike the anti-fibrotic effect of natural killer (NK) cells, CD8 and NK T subsets are considered as profibrogenic subsets. Padma Hepaten is a multi-compound herbal preparation derived from Tibetan medicine and has proven efficacy in some clinical trials and tests at the cellular level. In this study, we evaluate the immune efficacy of Padma Hepaten administered intraperitoneally (i.p.) and/or orally in a mice model of hepatic fibrosis. Hepatic fibrosis was induced by 6 weeks of biweekly i.p. carbon tetrachloride (CCl4) injections in male C57Bl6 mice. There were four groups, including naive mice, non-treated fibrotic mice and fibrotic mice treated by Padma Hepaten at weeks 5–6 of fibrosis induction either orally or by i.p. injections. Padma Hepaten was prepared at 10 mg/ml in saline and 250 µl (2·5 mg) were administered four times per week. After week 6, animals were killed. To isolate a Padma Hepaten-associated effect on lymphocytes, splenocytes were harvested from either naive or Padma Hepaten-treated non-fibrotic donors. Isolated splenocytes were therefore reconstituted into two groups of irradiated recipients. Recipients were then administered the same CCl4 regimen. Hepatic fibrosis was determined by sirius red staining of liver sections and by assessment of alpha smooth muscle actin expression compared with β-actin (both by mRNA as well as the protein liver extract western blotting). Hepatic fibrosis and alanine aminotransferase serum levels were decreased significantly in both Padma Hepaten-treated groups compared with the non-treated fibrotic group. Padma Hepaten treatment was associated with attenuation of lymphocyte subsets in both treated groups. Using a chemiluminescence technique to assess total anti-oxidant capacities (TAC), it was found that both the plasmas and livers of mice treated by CCl4 had significantly higher TAC compared with controls. However, the levels of TAC in animals treated either by CCl4 alone or CCl4 with Padma Hepaten were similar. Adoptive transfer of Padma Hepaten-treated lymphocytes was associated with fibrosis amelioration compared with recipients with naive lymphocytes. CCl4 generates higher levels of anti-oxidant capacities, probably as a response to oxidative stress. Padma Hepaten administration attenuated hepatic fibrogenesis significantly, accompanied by attenuation of lymphocyte but not anti-oxidant capacities. VL - 157 IS - 1 ER - TY - JOUR T1 -

Bacteria coated by polyphenols acquire potent oxidant-scavenging capacities

JF - Experimental Biology and Medicine Y1 - 2009 A1 - Ron Kohen A1 - Erez Koren A1 - H. Ovadia A1 - Isaac Ginsburg AB - Several microbial species, including probiotic lactic acid bacteria, have the ability to irreversibly bind a large variety of polyphenols (flavonoids) and anthocyanidins found in many colored fruits and vegetables and to enhance their total oxidant-scavenging capacities (TOSC). The binding of flavonoids to microbial surfaces was further increased by the cationic polyelectrolytes ligands poly-L-histidine, chlorhexidine and Copaxone. This phenomenon was confirmed visually, by the FRAP, DPPH, cyclic voltammetry, Folin-Ciocalteu as well as by luminol-dependent chemiluminescence techniques employed to assay TOSC. The possibility is considered that clinically, microbial cells in the oral cavity and in the gastro intestinal tract, complexed with antioxidant polyphenols from nutrients and with cationic ligands, might increase the protection of mammalian cells against damage induced by excessive generation of reactive oxygen species during infections and inflammation. VL - 234 IS - 8 ER - TY - JOUR T1 -

A cobalt-based tetrazolium salts reduction test to assay polyphenols.

JF - Journal of Agricultural and Food Chemistry Y1 - 2009 A1 - Erez Koren A1 - Ron Kohen A1 - Isaac Ginsburg AB - A novel assay was developed to measure the capacity of polyphenols to chelate cobalt(II) by using the reduction of the tetrazolium salts, NBT (nitroblue tetrazolium chloride), MTT (methylthiazolyldiphenyl-tetrazolium bromide), and XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide) to formazan products. The reduction of the salts is initiated by a cocktail comprised of cobalt(II), H(2)O(2), and selenium(IV), which generates hydroxyl radical, peroxide, and superoxide ions. However, because cobalt(II) could not be replaced either by Fe(II), Mn(II), or Cu(II), the classical Fenton transitional metals, it indicates that cobalt is the key player in the tetrazolium salt reduction. Micromolar concentrations of a large variety of antioxidant polyphenols and minute amounts of fruit beverages rich in polyphenols can readily chelate cobalt, resulting in the inhibition of the reduction of tetrazolium salt to formazan, in a dose-dependent manner. However, this method is unsuitable to measure low molecular weight antioxidants such as ascorbate, uric acid, and vitamin E since these have no chelating properties for cobalt(II). The newly described tetrazolium reduction method is as sensitive as the ferric ion reducing antioxidant power, 2,2-diphenyl-2-picrylhydrazyl hydrate, and the luminol-dependent chemiluminescence antioxidant assays. The practical advantages of using the newly described method to quantify polyphenol levels from various sources are briefly discussed. VL - 57 IS - 17 ER - TY - JOUR T1 -

Inflammaging - Altern als Konsequenz chronischer Entzündungen: Das Beispiel Padma 28.

JF - Swiss Journal of Integrative Medicine Y1 - 2008 A1 - Isaac Ginsburg A1 - Cécile Vennos A1 - Erez Koren AB - ZusammenfassungInflammaging bezeichnet einen chronischen Entzündungszustand, der durch altersbedingte Veränderungen des Immunsystems entsteht. Dieser wird als Grundlage vieler chronisch-entzündlicher Alterskrankheiten wie z.B. Arteriosklerose, Diabetes mellitus Typ 2, Morbus Alzheimer und Krebserkrankungen vermutet. Die Entstehung des vorherrschenden proinflammatorischen Milieus und der Verlauf des Entzündungsprozesses wird durch oxidativen Stress beschleunigt und in manchen Fällen verstärkt. Bei Entzündungsprozessen schütten aktivierte Immunzellen ein Arsenal an bioaktiven Stoffen aus, welche synergistisch zusammenwirken und neben positiven Wirkungen auch zu Zell- und Gewebeschäden führen. Im Fall einer manifesten Infektion sind ähnliche Prozesse beschrieben worden. Komplexe Phytotherapeutika (z.B. Padma 28) sind als pleiotrop wirkende Gemische geeignet, diesen krankmachenden Prozess an unterschiedlichen Wirkorten zu unterbinden. So sind etwa neben dem klinischen Effekt von Padma 28 bei Arteriosklerose auch verschiedene antiatherogene Wirkungsmechanismen des Präparats gut dokumentiert. Die Resultate stützen die Hypothese eines «multi- target»-Behandlungsansatzes von chronisch-entzündlichen Erkrankungen mit pflanzlichen Vielstoffgemischen, die hier einen wertvollen Betrag für neue Präventions- und Therapieverfahren liefern können. Sie sind somit geeignet, den Formenkreis von Inflammaging günstig zu beeinflussen, die Entstehung von Folgeerkrankheiten zu verlangsamen bzw. in manchen Fällen zu verhindern. VL - 20 IS - 7-8 ER - TY - JOUR T1 -

MDI 301, a nonirritating retinoid, improves abrasion wound healing in damaged/atrophic skin

JF - Wound Repair and Regeneration Y1 - 2008 A1 - RL. Warner A1 - N Bhagavathula A1 - K. Nerusu A1 - A. Hanosh A1 - SD. McClintock A1 - MK. Naik A1 - KJ. Johnson A1 - Isaac Ginsburg A1 - James Varani AB - MDI 301 is a picolinic acid-substituted ester of 9-cis retinoic acid. It has been shown in the past that MDI 301 increases epidermal thickness, decreases matrix metalloproteinase (MMP) activity, and increases procollagen synthesis in organ-cultured human skin. Unlike all-trans retinoic acid (RA), MDI 301 does not induce expression of proinflammatory cytokines or induce expression of leukocyte adhesion molecules in human skin. In the present study we examined topical MDI 301 treatment for ability to improve the structure and function of skin in three models of skin damage in rodents and for ability to improve abrasion wound healing in these models. MDI 301 was applied daily to the skin of rats treated with the potent corticosteroid, clobetasol propionate, to the skin of diabetic rats (8 weeks posttreatment with streptozotocin) and to the skin of aged (14-16-month-old) rats. In all three models, subsequently induced abrasion wounds healed more rapidly in the retinoid-treated animals than in vehicle-treated controls. Immediately after complete wound closure, tissue from the wound site (as well as from a control site) was put into organ culture and maintained for 3 days. At the end of the incubation period, culture fluids were assessed for soluble type I collagen and for MMPs-2 and -9. In all three models, the level of type I collagen was increased and MMP levels were decreased by MDI 301. In all three models, skin irritation during the retinoid-treatment phase was virtually nonexistent. VL - 16 IS - 1 ER - TY - JOUR T1 -

Supplementation with antioxidants fails to increase the total antioxidant capacity of several cell lines in culture

JF - Biomedicine & Pharmacotherapy Y1 - 2008 A1 - Erez Koren A1 - I. Zverev A1 - Isaac Ginsburg A1 - Ron Kohen AB - Low molecular weight antioxidants (LMWA) supplements are a popular and routine approach to assist the cell and the whole organism to cope with increasing oxidative stress. Numerous experiments have been conducted in which exogenous antioxidants were supplemented to cells, animals and humans to prevent and delay pathological disorders associated with reactive oxygen species. Recently, many meta-analysis publications have demonstrated the failure of this approach and in some cases even showed an increase in the severity of the disease and all-cause mortality. The reasons for the lack of success are not fully understood and the concept of antioxidant therapy is questionable. We suggest a new explanation concerning the way antioxidants function in the living cells that can elucidate some of the conflicting data published. The aim of this study was to examine the hypothesis that the overall antioxidant capacities of cells in culture remains constant and since the cells tightly regulate this antioxidant network, supplementation with exogenous antioxidants cannot enhance the total antioxidant capacity of the cells. This assumption was examined in HaCaT, Hep3B, PC3 and Caco-2 cells using several types of antioxidant supplements. It has been shown that while the levels of the specific administrated antioxidant increased significantly intracellularly, the overall antioxidant capacity of the cells as evaluated by various methods did not increase, and in some cases, even decreased. These results support the hypothesis and demonstrate that the total antioxidant capacity of these cells in culture is kept under tight regulation and cannot be enhanced by exogenous LMWA. VL - 62 IS - 3 ER - TY - JOUR T1 -

Are cationic antimicrobial peptides also 'double-edged swords'?

JF - Expert Review of Anti-infective Therapy Y1 - 2008 A1 - Isaac Ginsburg A1 - Erez Koren AB - The present view focuses on the possibility that cationic antimicrobial peptides (CAMPs) might, in addition to their killing effects due to permeabilization of microbial membranes, also function similarly to beta-lactam antibiotics to activate nascent autolytic wall enzymes, leading to bacteriolysis. Since the massive release of microbial cell wall components is a major cause of postinfectious sequelae, the in vivo process of bacteriolysis must be controlled. Due to the emergence of antibiotic resistance in pathogenic bacteria, CAMPs might be useful as an alternative to antibiotics. However, they should be used with caution, since they might also function as a 'double-edged sword' by injuring both the bacteria and host. VL - 6 IS - 4 ER - TY - JOUR T1 -

Interplay among oxidants, antioxidants, and cytokines in skin disorders: present status and future considerations.

JF - Biomedicine & Pharmacotherapy Y1 - 2007 A1 - M. Portugal A1 - Vivian Barak A1 - Isaac Ginsburg A1 - Ron Kohen AB - The pathogenicity of skin disorders involves a complexity of physiological, immunological, environmental, and genetic phenomena. This review focuses on cross-talks between two main agents, the oxidants and cytokines network, which have recently been found to play important roles in the pathophysiology of a large variety of skin disorders, including carcinogenesis, UVB irradiation damages, inflammatory processes, and a series of diseases such as, psoriasis, pyoderma gangrenosum, atopic dermatitis, irritant contact dermatitis, and bacterial skin infections. In particular the review discusses the question how an interplay between oxidants and cytokines might be beneficial in wound-healing and in therapeutic strategies in clinical settings. These involve topical applications and oral administration of antioxidant and inflammatory-cytokines-neutralizing antibodies. Monitoring cytokine expression in skin disorders (inflammatory versus anti-inflammatory, or Th1 versus Th2 types of cytokines) will definitely help to evaluate the severity of injury, its type, and its role in therapy. Furthermore, it is expected that future studies should explore the possible roles of the synergistic interactions between antioxidants and cytokines and their impact on the Th1/Th2 cytokine networks balances. VL - 61 IS - 7 ER - TY - JOUR T1 -

The reducing antioxidant capacity of Mycoplasma fermentans

JF - FEMS Microbiol Letters Y1 - 2006 A1 - A Yavlovich A1 - Ron Kohen A1 - Isaac Ginsburg A1 - S Rottem AB - Mycoplasma fermentans is an extracellular microorganism capable of adhering to the surface of host cells. It has been recently shown that plasminogen binding to M. fermentans in the presence of the urokinase-type plasminogen activator promotes the invasion of host cells by this organism. In this report, we show that viable mycoplasmas persist within the infected HeLa cells for prolonged periods of time despite the expectation that within host cells the organism may be exposed to oxidative stress. Using cyclic voltammetry and luminol-enhanced chemiluminescence assays, we detected a potent reducing antioxidant activity in M. fermentans. The reducing antioxidant activity was heat stable, not affected by proteolysis and was almost totally lost upon dialysis suggesting that the activity is due to a nonproteinaceus low molecular weight antioxidant. This antioxidant was partially purified by Bio-Gel column chromatography followed by high-pressure liquid chromatographic analysis. We suggest that the high reducing antioxidant capacity in M. fermentans is a principal defense mechanism playing a major role in the battle of the organism against oxidative stress within the host cells. VL - 259 IS - 2 ER - TY - JOUR T1 - Mechanism of vascular injury in acute lung inflammation JF - Research Advances in Pathology Y1 - 2005 A1 - James Varani A1 - Isaac Ginsburg VL - 1 ER - TY - JOUR T1 -

PADMA 28: a multi-component herbal preparation with retinoid-like dermal activity but without epidermal effects

JF - Journal of Investigative Dermatology Y1 - 2005 A1 - MN. Aslam A1 - H. Fligiel A1 - H Lateef A1 - GJ. Fisher A1 - Isaac Ginsburg A1 - James Varani AB - PADMA 28, a multi-component herbal mixture formulated according to an ancient Tibetan recipe, was assessed for effects on human dermal fibroblasts and epidermal keratinocytes in monolayer culture, and for effects on human skin in organ culture. PADMA 28 stimulated survival of fibroblasts in monolayer culture. In fibroblast monolayer culture and human skin organ culture, levels of matrix metalloproteinase-1 (MMP-1; interstitial collagenase) were reduced and type I procollagen production was increased. When keratinocytes were examined, there was no evidence of growth stimulation over a wide range of PADMA 28 concentrations. At high concentration, PADMA 28 inhibited keratinocyte proliferation. When organ cultures of human skin were treated with PADMA 28, there was no evidence of hyperplastic growth in the epidermis. Topical treatment of rhino mice with PADMA 28 failed to induce epidermal hyperplasia and was completely non-irritating. The ability to stimulate collagen production and inhibit the major collagen-degrading enzyme in skin without inducing a hyperplastic response in the epidermis may provide a basis for development of the herbal preparation as a "skin-repair" agent. VL - 124 IS - 3 ER - TY - JOUR T1 -

Mechanism of visible light phototoxicity on Porphyromonas gingivalis and Fusobacterium nucleatum

JF - Photochemistry and Photobiology Y1 - 2005 A1 - O. Feuerstein A1 - Isaac Ginsburg A1 - E. Dayan A1 - D. Veler A1 - E.I. Weiss AB - Phototoxicity of visible light laser on the porphyrin-producing bacteria, Porphyromonas gingivalis, in the absence of photosensitizers and under aerobic conditions was shown in previous studies. Recently, we found that the noncoherent visible light sources at wavelengths of 400-500 nm, commonly used in restorative dentistry, induced a phototoxic effect on P. gingivalis, as well as on Fusobacterium nucleatum, and to a lesser extent on the Streptococci sp. To elucidate the mechanism of this phototoxic effect, P. gingivalis and F. nucleatum were exposed to light (1) under aerobic and anaerobic environments and (2) in the presence of scavengers of reactive oxygen species (ROS). Phototoxic effect was not observed when the bacteria were exposed to light under anaerobic conditions. Dimethyl thiourea, a hydroxyl radical scavenger, was effective in reducing phototoxicity (P Intracellular location and survival of Mycoplasma penetrans within HeLa cells

JF - Current Microbiology Y1 - 2004 A1 - M. Tarshis A1 - A Yavlovich A1 - A. Katzenell A1 - Isaac Ginsburg A1 - S Rottem AB - Mycoplasma penetrans invades HeLa cells and survives within them for prolonged periods of time. The intracellular distribution of M. penetrans within HeLa cells was studied utilizing the acidotropic dye LysoTracker (green), which permeates cell membranes and upon protonation remains trapped in acidic compartments. The excitation and emission spectra of the green LysoTracker are suitable for colocalization studies with rabbit anti- M. penetrans antibodies and red Cy5 goat anti-rabbit IgG. The images collected by confocal laser scanning microscopy revealed that in the infected HeLa cells almost all Cy5 fluorescent foci (red) were located within the LysoTrack-labelled intracellular compartments, apparently endosomes. Viable mycoplasmas were detected within endosomes for prolonged periods of time, apparently due to a potent antioxidant activity detected in M. penetrans. VL - 49 IS - 2 ER - TY - JOUR T1 -

PADMA-28, a traditional Tibetan herbal preparation, blocks cellular responses to bFGF and IGF-I

JF - Inflammopharmacology Y1 - 2004 A1 - R Navab A1 - H Aingorn A1 - L Fallavollita A1 - S Sallon A1 - R Mechoulam A1 - Isaac Ginsburg A1 - Israel Vlodavsky A1 - P Brodt AB - The growth factors basic fibroblast growth factor (bFGF) and insulin-like growth factor 1 (IGF-I) have been implicated in the pathophysiology of atherosclerosis and restenosis. The Tibetan herbal preparation PADMA-28 (a mixture of 22 plants which is used as an anti-atherosclerosis agent) was tested for its ability to inhibit the mitogenic activity of bFGF and IGF-I, growth factors involved in restenosis, atherosclerosis and tumour progression. DNA synthesis and proliferation of vascular smooth muscle cells, in response to serum bFGF, thrombin, or combinations thereof, were abrogated in the presence of microgram amounts of both the aqueous and organic, partially purified, extracts of PADMA-28. These fractions also inhibited IGF-I-mediated proliferation, migration and invasion of tumour cells responsive to IGF-I. The inhibition by PADMA 28 was reversible upon removal of the PADMA extracts, indicating that the effects were not related to cell toxicity. These and other properties (i.e., anti-oxidant activity) of PADMA-28 may be responsible for its beneficial effect as an anti-atherosclerotic agent, suggesting that this herbal preparation may have potential applications in the prevention of intimal hyperplasia and arterial stenosis secondary to coronary angioplasty and bypass surgery, as well as in the prevention and treatment of other vascular diseases and tumour growth and metastasis. VL - 12 IS - 4 ER - TY - JOUR T1 -

Novel chemiluminescence-inducing cocktails, part I: the role in light emission of combinations of luminal with SIN-1, selenite, albumin, glucose oxidase and Co2+

JF - Inflammopharmacology Y1 - 2004 A1 - Isaac Ginsburg A1 - Milu Sadovnik A1 - M. Oron A1 - Ron Kohen AB - It is known that many agents influence the capacity of cells to produce reactive oxygen species. However, assaying these agents, both those that stimulate and those that inhibit reactive oxygen production, can be complicated and time consuming. Here, a method is described in which two different cocktails are employed to stimulate luminol-dependent chemiluminescence (LDCL). These cocktails are comprised of luminol, with either sodium selenite [IV] (SEL) or tellurite [IV] (TEL) (where IV and VI refer to the 4+ or 6+ oxidation state of selenium or tellurium salts, respectively), morpholinosidonimine (SIN-1), serum albumin and Co(2+), called the SIN-1a (with selenite) and SIN1b (with tellurite) cocktails, respectively; or luminol with glucose oxidase (GO), sodium selenite [IV] and Co(2+), called the GO cocktail. The cocktails functioned best in Hank's balanced salt solution (HBSS) containing 1% glucose at pH 7.4, incubated at approximately 22 degrees C. Within 30-60 s there was a burst of luminescence, which lasted for 7-10 min. In 100% ethanol, the SIN-1 cocktails also generated LDCL to 70% of that produced in HBSS. Neither selenite [VI], seleno-cystine, seleno-methionine, nor the selenium-containing drug, ebselen, could replace SEL. Moreover, the effects of the NO-donor, SIN-1, could not be replicated by the oxyradical generators, xanthine-xanthine oxidase or hypochlorous acid. Only low levels of luminescence were generated by combinations of the peroxyl radical generator, 2,2'-azobis-2-amidinopropane dihydrochloride (AAPH) with either SEL or TEL. It is suggested that light emission induced by the SIN1 cocktail results from the oxidation of SEL [IV] to the [VI] state, possibly due to the generation of mixtures of superoxide, peroxide, peroxynitrite and also of unidentified oxidant species, catalyzed by CoCo(2+). However, the involvement of hydroxyl radicals in LDCL could not be confirmed by use of either dimethyl thiourea or by electron spin resonance (ESR). LDCL induced by the two cocktails is strongly reduced by phosphates, EDTA, deferoxamine, CuCo(2+), MnCo(2+), as well as by the "classical" antioxidants superoxide dismutase (SOD), ascorbate, vitamin E, uric acid or thiols. It is suggested that these chemiluminescence cocktail systems can be used to determine the total anti-oxidant capacities of biological fluids and commercially available anti-oxidants. VL - 12 IS - 4 ER - TY - JOUR T1 -

Novel chemiluminescence-inducing cocktails, part II: measurement of the anti-oxidant capacity of vitamins, thiols, body fluids, alcoholic beverages and edible oils.

JF - Inflammopharmacology Y1 - 2004 A1 - Isaac Ginsburg A1 - M. Sadovnic A1 - M. Oron A1 - Ron Kohen AB - Using two luminescence-inducing cocktails, two distinct patterns of inhibition of light by different anti-oxidants have been identified, comprising Group A, in which a complete inhibition of light emission which is then followed by re-emergence of light, forming apparent S-shaped curves or similar shapes. This light pattern is induced by the "classical" anti-oxidants, ascorbate, vitamin E, uric acid, thiols, deferoxamine, as well as by anti-oxidant agents present in plasma, saliva, urine and in extracts derived from black coffee, and Group B, in which a gradually emerging "mound"-shaped pattern of light was seen with extracts from the Tibetan plant mixture PADMA-28, elderberry (Sambucol), grape seeds, green and black teas, apple, parsimony, red wines, edible oils and SOD. While the results with the Group A agents point to the presence of probably a single, major, anti-oxidants relatively sensitive to oxidation, Group B agents probably include a mixture of anti-oxidants which are more resistant to oxidation. It was also shown that agents from Group B could protect agents from Group A against consumption by the oxidants generated by the cocktails. It is proposed that these simple to use cocktails which probably generate a multiplicity of oxidants mimicking those generated by activated phagocytes, can rapidly assess the total anti-oxidant capacities (TAOC) in body fluids derived from patients suffering of excessive oxidative stress. Also, this technique may be useful in determining the content of dietary anti-oxidants recommended as supplements to enhance the resistance against excessive oxidation of lipids. VL - 12 IS - 4 ER - TY - JOUR T1 -

Bactericidal cationic peptides can also function as bacteriolysis-inducing agents mimicking beta-lactam antibiotics?; it is enigmatic why this concept is consistently disregarded.

JF - Medical Hypotheses Y1 - 2004 A1 - Isaac Ginsburg AB - Although there is a general consensus that highly cationic peptides kill bacteria primarily by injuring their membranes, an additional hypothesis is proposed suggesting that a large variety of cationic peptides might also render bacteria non viable by activating their autolytic wall enzymes - muramidases (a "Trojan Horse" phenomenon), resulting in bacteriolysis. This group of cationic peptides includes: lysozyme, lactoferrin, neutrophil-derived permeability increasing peptides, defensins, elastase, cathepsin G, and secretory phopholipase A2. In this respect, cationic peptides mimic the bactericidal/bacteriolytic effects exerted by of beta-lactam antibiotics. Bacteriolysis results in a massive release of the pro-inflammatory cell-wall components, endotoxin (LPS), lipoteichoic acid (LTA) and peptidoglycan (PPG), which if not effectively controlled, can trigger the coagulation and complement cascades, the release from phagocytes of inflammatory cytokines, reactive oxygen and nitrogen species, and proteinases. Synergism (a "cross-talk") among such agonists released following bacteriolysis, is probably the main cause for septic shock and multiple organ failure. It is proposed that a use of bacteriolysis-inducing antibiotics should be avoided in bacteremic patients and particularly in those patients already suspected of developing shock symptoms as these might further enhance bacteriolysis and the release of LPS, LTA and PPG. Furthermore, in additonal to the supportive regimen exercised in intensive care settings, a use of non bacteriolysis-inducing antibiotics when combined with highly sulfated compounds (e.g. heparin, and other clinically certified polysufates) should be considered instead, as these might prevent the activation of the microbial own autolytic systems induced either by highly cationic peptides released by activated phagocytes or by the highly bacteriolytic beta-lactams. Polysulfates might also depress the deleterious effects of the complement cascade and the use of combinations among anti-oxidants ( N-acetyl cysteine), proteinase inhibitors and phospholipids might prove effective to depress the synergistic cytotoxic effects induced by inflammatory agonists. Also, a use of gamma globulin enriched either in anti-LPS or in anti-LTA activities might serve to prevent the binding of these toxins to receptors upon macrophage which upon activation generate inflammatory cytokines. Thus, a use of "cocktails" of anti-inflammatory agents might replace the unsuccessful use of single antagonists proven in scores of clinical trials of sepsis to by ineffective in prolonging the lives of patients. It is enigmatic why the concept, and the publications which support a role for cationic peptides also as potent inducers of bacteriolysis, an arch evil and a deleterious phenomenon which undoubtedly plays a pivotal role in the pathophysiology of post-infectious sequelae, has been consistently disregarded. VL - 62 IS - 3 ER - TY - JOUR T1 -

 

 

PADMA-28, a Tibetan herbal preparation is an inhibitor of inflammatory cytokine production

JF - European Cytokine Network Y1 - 2004 A1 - Vivian Barak A1 - Inna Kalickman A1 - Tal Halperin A1 - Shlomo Birkenfeld A1 - Isaac Ginsburg AB - BACKGROUND: Previous studies have shown that PADMA-28, a multicomponent, traditional Tibetan herbal plant preparation possesses a variety of beneficial effects on several experimental models of inflammatory and immune processes, including autoimmune diabetes and autoimmune encephalomyelitis. In humans, PADMA-28 attenuated the symptoms associated with intermittent claudications in atherosclerotic patients. OBJECTIVE: To assess the effect of PADMA 28 on the immune system, e.g. cytokine (interleukins) production. DESIGN: Cytokine production by human blood monocytes (derived from 12 healthy donors) stimulated in vitro, either by endotoxin (LPS) from Salmonella typhi or by lipoteichoic acid (LTA) from group A Streptococci was modulated by PADMA-28. RESULTS: The present study showed that an aqueous extract of PADMA-28 strongly decreased the production of the inflammatory cytokines IL-1beta, IL-6, IL-8 and TNF-alpha, and more moderately, also decreased the anti-inflammatory cytokine IL-10 induced by LPS. However, the LTA - induced IL-10 production was [not significantly] increased by the low dose PADMA-28, while not effected at all by the higher dose of PADMA-28. CONCLUSIONS: The data from these finding suggest a possible clinical efficacy of PADMA-28 either in autoimmune and in inflammatory conditions or in post-inflammatory sequelae, as previously shown in in vivo and human studies, probably by decreasing inflammatory cytokines. VL - 15 IS - 3 ER - TY - JOUR T1 -

Cationic polyelectrolytes from leukocytes might kill bacteria by 

activating their autolytic systems: Enigmatically, the relevance 

of this phenomenon to post-infectious sequelae is disregarded

JF - Intensive Care Medicine Y1 - 2002 A1 - Isaac Ginsburg AB - Linear polymers of lysine and arginine, phagocyte-derived lysozyme, PLA, elas- tase, cathepsin G, myeloperoxidases, nu- clear histone and bacterial/permeability-en- hancing peptide (BPI) and defensins all possess bactericidal activities [1, 2, 3, 4, 5, 6]. The highly cationic BPI and defensins might kill Gram-negatives primarily by de- polarizing their outer membrane to en- hance its permeability [3]. However, it had also been proposed that many of these polycations might also function as “Trojan Horses” to disrupt the intracellular regula- tion of the autolytic wall enzyme systems (muramidases).This can lead to cleavage of the peptidoglycan, to bacteriolysis, and to cell death [4, 5, 6].The highly cationic, ly- sozyme, PLA2, and elastase probably do not function solely as enzymes, but rather as highly cationic agents. The bactericidal and bacteriolytic effects of polycations might therefore mimic the bacteriolytic ef- fects caused by beta-lactam antibiotics. Sulfated compounds (heparin, dextran sul- fate, polyaenthole sulfonate) very efficient- CORRESPONDENCE ly inhibited the activation of bacterial au- tolysis induced either by cationic agents or by beta-lactam antibiotics [4, 5, 6, 7]. Therefore, it is highly likely that polycat- ions of plasma and leukocyte origins might be actively involved in the pathophysiolo- gy of post-infectious sequelae by their ca- pacity to induce a massive release of high- ly phlogistic lipoteichoic acid [7] endotox- in, lipoprotein, and peptidoglycan [8]. Combinations among these agents might act on mononuclear cells to generate reactive oxygen species, NO, NOO-, hy- drolases, and also to activate the coagula- tion, complement, and cytokine cascades, all involved in septic shock. Based on the above arguments, it is tempting to specu- late that the failure to depress early bacteri- olysis in the bloodstream might be the main cause for the inability to cope with the multiple synergistic interactions lead- ing to post-infectious sequelae [9]. The clinical use of polyanions when combined with mutli drug strategies might therefore be recommended as potent anti-bacteriolyt- ic and anti-inflammatory agents [10]. It is enigmatic why publications that have pro- posed the role of polycations in bacterioly- sis and the possibility to inhibit its unto- ward effects by polyanions, findings so rel- evant to the patholysiology of post-infec- tious sequelae, are consistently disregarded [11] either in basic science publications on the bactericidal effects of polycations or in the clinical literature dealing with post-in- fectious sequelae. VL - 28 IS - 8 ER - TY - JOUR T1 -

Hemolysis of human erythrocytes by hypochlorous acid is modulated by amino acids, antioxidants, oxidants, membrane-perforating agents and by divalent metals

JF - Free Radical Research Y1 - 2002 A1 - Isaac Ginsburg A1 - Milu Sadovnik A1 - S. Yedgar A1 - Ron Kohen A1 - J. Hrbac AB - The optimal conditions under which hypochlorous acid (NaOCl) either hemolyzes human RBC or kills monkey kidney epithelial cells (BGM) in culture had been investigated. While in Hank's balanced salt solution (HBSS), micromolar amounts of NaOCl caused full hemolysis and also killed BGM cells, in D-MEM or RPMI media rich in amino acids, 25-40 mM of hypochlorite were needed to induce cell injury. Cells exposed to high amounts of NaOCl became highly refractory to strong detergents. Hemolysis by NaOCl was strongly inhibited by a large variety of antioxidants. RBC treated by subtoxic concentrations either of peroxide, peroxyl radical, NO, cholesterol, PLA2, PLC as well as by N2, argon or by mixture of CO2 (10%) and O2 (90%) became much more susceptible to lysis by NaOCl. On the other hand, while RBC treated by Fe2+, Co2+, and V2+ and to a lesser extent with Cu2+ became highly resistant to NaOCl hemolysis presumably due to NaOCl decomposition, no such effect was found either with Co2+ or by Mn2+. RBC treated by azide to destroy catalase and then incubated with peroxide and with NaOCl failed to undergo hemolysis due to the ability of peroxide to decompose NaOCl. The inhibitory effects of the divalent metals on NaOCl-induced hemolysis were also substantiated by measuring the decrease in pH and by cyclic voltammetry. The findings that like peroxide, NaOCl also synergizes with membrane-perforating agents and with a protease to kill epithelial cells further implicate such "cocktails" in cell injury in inflammatory conditions. Taken together, because of the capacity of many agents to scavenge NaOCl, tissue damage by NaOCl-generated neutrophils can take place primarily if activated neutrophils closely adhere to target cells to avoid the scavenging effects of amino acids and of antioxidants. Therefore, the significance of the data which had tested the cytotoxic effects of NaOCl using cells suspended only in salt solutions, should be reconsidered. VL - 36 IS - 6 ER - TY - JOUR T1 -

Role of lipoteichoic acid in infection and inflammation

JF - The Lancet Infectious Diseases Y1 - 2002 A1 - Isaac Ginsburg AB - Lipoteichoic acid (LTA) is a surface-associated adhesion amphiphile from Gram-positive bacteria and regulator of autolytic wall enzymes (muramidases). It is released from the bacterial cells mainly after bacteriolysis induced by lysozyme, cationic peptides from leucocytes, or beta-lactam antibiotics. It binds to target cells either non-specifically, to membrane phospholipids, or specifically, to CD14 and to Toll-like receptors. LTA bound to targets can interact with circulating antibodies and activate the complement cascade to induce a passive immune kill phenomenon. It also triggers the release from neutrophils and macrophages of reactive oxygen and nitrogen species, acid hydrolases, highly cationic proteinases, bactericidal cationic peptides, growth factors, and cytotoxic cytokines, which may act in synergy to amplify cell damage. Thus, LTA shares with endotoxin (lipopolysaccharide) many of its pathogenetic properties. In animal studies, LTA has induced arthritis, nephritis, uveitis, encephalomyelitis, meningeal inflammation, and periodontal lesions, and also triggered cascades resulting in septic shock and multiorgan failure. Binding of LTA to targets can be inhibited by antibodies, phospholipids, and specific antibodies to CD14 and Toll, and in vitro its release can be inhibited by non-bacteriolytic antibiotics and by polysulphates such as heparin, which probably interfere with the activation of autolysis. From all this evidence, LTA can be considered a virulence factor that has an important role in infections and in postinfectious sequelae caused by Gram-positive bacteria. The future development of effective antibacteriolitic drugs and multidrug strategies to attenuate LTA-induced secretion of proinflammatory agonists is of great importance to combat septic shock and multiorgan failure caused by Gram-positive bacteria. VL - 2 IS - 3 ER - TY - JOUR T1 -

The role of bacteriolysis in the pathophysiology of inflammation, infection and post-infectious sequelae

JF - APMIS Y1 - 2002 A1 - Isaac Ginsburg AB - The literature dealing with the biochemical basis of bacteriolysis and its role in inflammation, infection and in post-infectious sequelae is reviewed and discussed. Bacteriolysis is an event that may occur when normal microbial multiplication is altered due to an uncontrolled activation of a series of autolytic cell-wall breaking enzymes (muramidases). While a low-level bacteriolysis sometimes occurs physiologically, due to "mistakes" in cell separation, a pronounced cell wall breakdown may occur following bacteriolysis induced either by beta-lactam antibiotics or by a large variety of bacteriolysis-inducing cationic peptides. These include spermine, spermidine, bactericidal peptides defensins, bacterial permeability increasing peptides from neutrophils, cationic proteins from eosinophils, lysozyme, myeloperoxidase, lactoferrin, the highly cationic proteinases elastase and cathepsins, PLA2, and certain synthetic polyamino acids. The cationic agents probably function by deregulating lipoteichoic acid (LTA) in Gram-positive bacteria and phospholipids in Gram-negative bacteria, the presumed regulators of the autolytic enzyme systems (muramidases). When bacteriolysis occurs in vivo, cell-wall- and -membrane-associated lipopolysaccharide (LPS (endotoxin)), lipoteichoic acid (LTA) and peptidoglycan (PPG), are released. These highly phlogistic agents can act on macrophages, either individually or in synergy, to induce the generation and release of reactive oxygen and nitrogen species, cytotoxic cytokines, hydrolases, proteinases, and also to activate the coagulation and complement cascades. All these agents and processes are involved in the pathophysiology of septic shock and multiple organ failure resulting from severe microbial infections. Bacteriolysis induced in in vitro models, either by polycations or by beta-lactams, could be effectively inhibited by sulfated polysaccharides, by D-amino acids as well as by certain anti-bacteriolytic antibiotics. However, within phagocytic cells in inflammatory sites, bacteriolysis tends to be strongly inhibited presumably due to the inactivation by oxidants and proteinases of the bacterial muramidases. This might results in a long persistence of non-biodegradable cell-wall components causing granulomatous inflammation. However, persistence of microbial cell walls in vivo may also boost innate immunity against infections and against tumor-cell proliferation. Therapeutic strategies to cope with the deleterious effects of bacteriolysis in vivo include combinations of autolysin inhibitors with combinations of certain anti-inflammatory agents. These might inhibit the synergistic tissue- and- organ-damaging "cross talks" which lead to septic shock and to additional post-infectious sequelae. VL - 110 IS - 11 ER - TY - JOUR T1 -

A psychometric study of patients with nail dystrophies

JF - Journal of the American Academy of Dermatology Y1 - 2001 A1 - M. Alam A1 - M. Moossavi A1 - Isaac Ginsburg A1 - RK Scher AB - BACKGROUND: Survey studies suggest that patients with various dermatologic conditions experience concomitant psychologic distress. OBJECTIVE: The purpose of this study was to determine which types of psychologic distress may be correlated with dystrophic disease of the nail in nonpsychiatric patients. METHODS: Fifty-seven adult subjects presenting for treatment of nail dystrophies completed a survey instrument, which included 5 psychometric measures. RESULTS: On average, patients rated the severity of their nail dystrophy and functional deficit higher (7.40/10 and 6.00, respectively) than investigators (6.15 and 3.75, respectively). Compared with age- and sex-matched nonpsychiatric patients, subjects in the study were moderately more anxious and minimally to mildly more depressed. Subjects had moderately depressed total self-concept, but their body image was approximately normal. Overall, subjects exhibited markedly more severe psychologic symptoms (84th percentile) than the normal sample, with the scores on the psychoticism, obsessive-compulsive, and paranoid ideation subscales being the most elevated. CONCLUSION: The subjects with nail dystrophy had markedly exacerbated psychologic symptoms compared with age- and sex-matched nonpsychiatric patients. VL - 45 IS - 6 ER - TY - ABST T1 -

Disregard of Pre-Medline Literature and the Future of Honest Science

Y1 - 2001 A1 - Isaac Ginsburg AB - As we enter the third millennium, we witness the rapid continuation of the unprecedented explosion of scientific information. Today, we are fortunate to have access to Medline and to electronic journals covering the mammoth fields of biological sciences. It presumably assures us that we can no longer miss important relevant recent publications crucial to the continuation of our original line of research. Unfortunately, we witness today a dangerous trend that despite having access to Index Medicus and additional abstracting systems covering the literature prior to 1960, younger investigators tend to refrain from citing "older" publications, assuming that they are already passe. Obviously, it necessitates spending time in libraries. But who, in these "modern" computerized days, has time to wait? Over the last few years, I tried to find out what was behind this behavior. I took the liberty of writing to authors who published papers in my own field of research and who failed to cite crucial key publications from the pre-Medline era, without which I believe they cannot even start to understand the evolution of their own current research. The following are only several of the responses I received: "I do not read the Journals which you claimed had included papers relevant for my research paper." "I was unaware of the publications you proposed, but will be happy to read them if you can send them to me. I might consider citing them in my future review on the subject." "Restrictions over the numbers of reference permissible prevented me from citing the proposed articles." "The library at my university gives me a hard time trying to retrieve older literature." "The focus of my article was to narrow down only on the most relevant current information available on the subject." "Reviews covering the topic of my current investigations had recently been published." (However, no such review was cited by the author.) "I do not have the time to comment on your thoughts in a scholarly fashion. However, bear in mind that the papers you had listed have not gone completely unnoticed." (Really?) "You will recognize that it is not easy to find papers from several years unless they are cited by others, as there is literally too much information about" "As a newcomer to this field of research, I neglected to read relatively old articles and I restricted myself to critically report the most common views on the subject. Besides, I was unable to receive the older articles you mentioned, because they are unavailable in the library of our relatively new university." "I had, as you guessed, not seen your work. I am unfamiliar with most of the journals in which you publish—-and also I am not an immunologist." The following is also a reminder how certain line of research might become extinct. A review on the role of proteinases in tissue damage concluded that proteinases might also synergize with oxidants and with additional pro-inflammatory agents. Yet, publications since 1960 which had described this phenomenon had not been included either in this particular paper or in any of the papers on the subject. A main line of research had proposed that cationic proteins from leukocytes might kill bacteria by altering the permeability of their membranes. Yet, none of a very large series of investigations by others since the early 1970s, which had proposed an alternative possible mechanism suggesting that cationic proteins might kill microorganisms also by their ability to induce bacteriolysis, are ever cited anywhere. Because of a change in nomenclature, pioneering investigations from 1951-1957, which had described the properties and mechanisms of action of bacterial cell-sensitizing agents (HF), had literally been eliminated because today this factor is called lipoteichoic acid (LTA). One simple sentence, and including proper citations stressing that LTA was previously called HF, might have sufficed to prevent unnecessary repetitions of the same experiments. The following proposals might be adopted by editorial boards of journals to assure and also fight against the "disregard syndrome." (i) Every paper should include an introductory historical coverage of the "pioneering" investigations on which the current research is based. (ii) Emeriti professors, who might have read "older investigations" in a particular field of research, be nominated as referees. This might also stimulate emeriti professors to be reinvolved in the activities of the scientific community. (iii) A "Letters to the Editor" section in every Journal be established where authors can alert their readers to the existence of "old" literature on the subject. (iv) To combat the unacceptable attitude where publications which do not "fit" current thoughts and ideas are simply concealed from the modern reader. This is unethical and also self-defeating. Only a strong stand by Editorial Boards against the "disregard syndrome" might help to advance honest science. JF - ASM News- Letters to the editor VL - 67 IS - 7 ER - TY - JOUR T1 -

The Disregard Syndrome: A Menace to Honest Science?

JF - The Scientist Y1 - 2001 A1 - Isaac Ginsburg AB - We are witnessing the continuation of an accelerated, unprecedented explosion of scientific information that might make the life of a serious investigator unbearably complicated. Unlike our pioneering investigators, however, we are fortunate to have access to modern information-retrieving pools such as Medline, Biological Abstracts, and more recently selected electronic journals. These allow us, at the press of a key, to choose desired scientific citations. A search for articles in the medical VL - 15 IS - 24 ER - TY - JOUR T1 -

HYPOTHESIS: Is a Failure to Prevent Bacteriolysis and the Synergy Among Microbial and Host-Derived Pro-Inflammatory Agonists the Main Contributory Factors to the Pathogenesis of Post-Infectious Sequelae?

JF - Inflammation Y1 - 2001 A1 - Isaac Ginsburg AB - INTRODUCTION Why Have Clinical Trials of Sepsis Been Unsuccessful? It is disconcerting that entering the third millennium, severe microbial infections and their sequelae e.g., sep- sis, septic shock, ARDS, “flesh-eating syndromes,” still claim the lives of numerous patients annually. Further- more, it is of great interest that while immunomodu- lating agents have proved beneficial in the treatment of inflammatory conditions such as rheumatoid arthri- tis, a large series of clinical trials which have been con- ducted in the last decade and which have mainly tested only single immunomodulating agents as therapies for septic shock, have been mostly unsuccessful. In 1996, Verhoef et al. (1) have stated that reviewing the liter- ature on sepsis therapies “the area of immunomodula- tion has now become an area of more realism and the results of early trials have forced investigators to go back to the drawing board to re-investigate the whole con- cept of immunotherapy and immunoprophylaxis. In a more recent Point of View in Critical Care Medicine, entitled “Sepsis research: We must change course,” Dr. Nasraway has hit the nail on its head (2). Reviewing the disappointing results of no less than 29 prospec- tive controlled studies of human sepsis performed in the last decade, he has questioned whether “it is rational to attempt to alter the inflammatory responses by admin- istering a single immunomodulating agent while simul- taneously failing to control for the many interventions that also alter cytokine expression?” He has also raised serious doubts about the morality of any future trials of sepsis if conducted in the present manner. Baue (3), Opal and Yu (4), Cross et al. (5), Teplick and Ruben (6) and Abraham (7), have recently assessed the state of the art in sepsis research prevention and treatment, the reasons why the trials of sepsis have invariably failed to prolong the lives of septic patients, the hazards involved in the future use of multidrug strategies in sepsis, and the con- tributions of animal models to the development effec- tive therapeutic regimens in humans. Reading through the extensive literature on sepsis research and treatment, it was surprising to realize that no less than 35 different anti-inflammatory agents and strategies have been rec- ommended, usually singly, to cope with post-infectious sequelae (in 1–13). It is however important to stress that, at the bedside, anti-inflammatory agents are too often administered to patients when the deleterious pathophys- iological cascades leading to septic shock and organ fail- ure have already been irreversibly initiated. Therefore, one cannot avoid assuming that the recommendations to test only one antagonist, at time, to suppress the patho- physiological cascades in sepsis and septic shock, might have been unrealistic to begin with and also erroneous. Presumably, these have been based on the concept that there might exist a single “omnipotent” pro-inflamma- tory agonist generated following microbial invasions of the blood stream, which is efficiently neutralized, on time, might inhibit the multiple pathophysiological cas- cades responsible for the sepsis syndrome. Also, the use of multidrug strategies (4, 5, 8, 13) has been ham- pered by reports warning against the hazards of combi- nation therapies in sepsis (4, 5, 16). Is it possible that, today, sepsis research has reached a dead end because of “flawed concept or faulty implementation?” (5). Results from animal models have clearly indicated that the inhibition of septic shock induced either by endotoxin (LPS), lipoteichoic acid (LTA), peptidogly- can (PPG) or by viable microbial cells, has been mostly successful only if the anti-inflammatory agent has been administered prior to microbial challenge. This strongly suggests that the main obstacle facing clinicians at the bedside is that once sepsis symptoms have appeared, it might already be too late to effectively prevent the pathophysiological cascades leading to tissue damage and organ failure. Therefore, strategies to prevent sep- tic shock and of additional post-infectious sequelae in humans should inonvolve distinct preventive measures especially in defined groups of high-risk patients (3–13). VL - 25 IS - 1 ER - TY - JOUR T1 -

Cationic peptides from leukocytes might kill bacteria by activating their autolytic enzymes causing bacteriolysis: why are publications proposing this concept never acknowledged?

JF - Blood Y1 - 2001 A1 - Isaac Ginsburg AB - A large series of publications1-9 has proposed that cationic peptides from leukocytes kill bacteria primarily by causing a depolarization of their membranes leading to enhanced permeability. One group of cationic peptides from human neutrophils was even coined bactericidal/permeability-increasing proteins.3Surprisingly, however, none of a large series of other publications that had proposed a concept that cationic agents from neutrophils might be bactericidal also by virtue of their capacity to activate the bacterial autolytic wall enzymes (muramidases), leading to bacteriolysis and cell death,10-22 has ever been cited in any of the publications by the leading authors in this field of research.1-9 For the information of your readers, there exist a series of 16 publications since 1974 entitled “Effect of leukocyte hydrolases on bacteria” and several additional publications on the same subject under different titles, many of them published in journals covered by Medline; the references contain a selected list of these.10-22 24 These had proposed that many of the highly cationic agents either present in plasma or generated by activated phagocytes (eg, lysozymes, PLA2, elastase, cathepsin G, myeloperoxidase, bactericidal/permeability-increasing proteins, defensins, etc) might kill bacteria not simply by acting on the membranes to cause depolarization and enhanced permeability1-7 but also by an indirect mechanism. This involves a deregulation, by the cationic agents, of the anionic and amphiphilic regulators of the autolytic wall enzymes(muramidases) (lipoteichoic acid in Gram-positives and Forssman antigens in Gram-negatives)16 17 23-25 resulting in hydrolysis of the peptidoglycan, in bacteriolysis, and in cell death. It is of great clinical importance that the bacteriolysis-inducing activity of cationic agents mimics that of beta-lactam antibiotics.26 Furthermore, the observations that a variety of highly negatively charged, sulfated anionic agents can act as potent inhibitors of the cationic agent– and beta-lactam–induced bacteriolysis11 12 14 16 17 27-30further stress the importance of the autolytic systems in bacterial killing. This phenomenon might also be of great clinical significance especially in selecting measures to control postinfectious sequelae that undoubtedly are triggered by the release of bacterial components, especially following bacteriolysis. Regrettably, attempts to bring these issues to the awareness of the leading investigators in the field of cationic proteins1-9and of clinicians involved is the clinical aspects of sepsis control have not been successful. If the concept that cationic agents might be bactericidal also because of their bacteriolysis-inducing properties is reasonable and scientifically sound, it is expected that publications describing this phenomenon should be cited by authors studying the bactericidal effects of cationic agents. If on the other hand one deems that this concept is for some reason erroneous, nonsensical, and scientifically unacceptable, such publications should definitely be cited but properly discussed, challenged, and even also ridiculed. But it is totally unacceptable and unreasonable that such publications be simply ignored! Unfortunately, the avoidance of relevant citations and the disregard for concepts that might perhaps not “fit” current dogma and beliefs have reached epidemic levels. This is how pioneering publications proposing “novel approaches and ideas”16 17 29 30 to explain additional mechanisms of microbial killing might be lost forever. More importantly, these concepts will probably never reach the attention of clinicians interested in the pathogenesis of inflammation, infection, postinfectious sequelae, and the mechanisms of host defense.29-31 But what is even more disturbing, concerning, and unacceptable is that the expert referees selected by the editorial boards of journals and who should have been knowledgeable of the relevant literature failed to alert the authors to the existence of key publications on bacteriolysis so relevant to the subject of the papers and of the reviews they had been assigned to judge. Am I wrong to assume that the task of a journal's editorial board is to ensure that all viewpoints and ideas, both “conventional” and nonconventional, be equally represented? Excuses either that limitations to the number of references permissible were the reason for not citing basic and pioneering publications or that the authors had been “instructed” to discuss only a narrow field of research and to disregard others fields with direct relevance are unacceptable. A failure to give credit to relevant papers is also unacademic, self-defeating, unethical, and therefore unacceptable by all standards. Furthermore, are papers older than 15 years, or so, already passéand, therefore, unworthy of being acknowledged? VL - 97 IS - 8 ER - TY - JOUR T1 -

Perioperative alterations in plasma endothelin-1 and echocardiographic correlates of right heart function

JF - Journal of Cardiothoracic and Vascular Anesthesia Y1 - 2000 A1 - D. Amar A1 - M. Fleisher A1 - D.H.Y. Leung A1 - H. Zhang A1 - Isaac Ginsburg A1 - N. Roistacher AB - OBJECTIVE: To determine whether greater changes in plasma endothelin-1 (ET-1) concentrations and right ventricular systolic pressure occur after major thoracic surgery than after major abdominal operations. DESIGN: Prospective study. SETTING: University hospital. PARTICIPANTS: Patients undergoing elective thoracotomies (n = 12) or laparotomies (n = 10). INTERVENTIONS: ET-1 was measured from blood obtained before anesthesia and again on postoperative days 1, 2, 3, and 5 (or 6). Transthoracic echocardiography was performed before surgery and on postoperative day 2 to evaluate right-sided heart function. MEASUREMENTS AND MAIN RESULTS: After abdominal and thoracic surgery, systemic and estimated pulmonary vascular pressures were normal in both groups and unaffected by surgery. Plasma ET-1 concentrations decreased from baseline values during the first postoperative week with no differences between the groups. CONCLUSIONS: In patients without organic heart disease, plasma ET-1 levels do not increase in response to major abdominal or thoracic surgery. Whether or not plasma ET-1 concentrations are elevated in patients developing clinically significant postoperative pulmonary hypertension requires further study. VL - 14 IS - 2 ER - TY - JOUR T1 -

 

Effects of diltiazem prophylaxis on the incidence and clinical outcome of atrial arrhythmias after thoracic surgery

JF - Journal of Thoracic and Cardiovascular Surgery Y1 - 2000 A1 - D. Amar A1 - N. Roistacher A1 - VW Rusch A1 - D.H.Y. Leung A1 - Isaac Ginsburg A1 - H. Zhang A1 - MS Bains A1 - RJ Downey A1 - RJ. Korst A1 - RJ. Ginsberg AB - OBJECTIVES: We sought to determine whether early prophylaxis with an L -type calcium channel blocker reduces the incidence and morbidity associated with atrial fibrillation/flutter and supraventricular tachyarrhythmia after major thoracic operations. METHODS: In this randomized, double-blind, placebo-controlled study, 330 patients were given either intravenous diltiazem (n = 167) or placebo (n = 163) immediately after lobectomy (> or =60 years) or pneumonectomy (> or =18 years) and orally thereafter for 14 days. The primary end point with respect to efficacy was a sustained (> or =15 minutes) or clinically significant atrial arrhythmia during treatment. RESULTS: Postoperative atrial arrhythmias (atrial fibrillation/flutter = 60; supraventricular tachyarrhythmias = 5) occurred in 25 (15%) of the 167 patients in the diltiazem group and 40 (25%) of the 163 patients in the placebo group (P = .03). When compared with placebo, diltiazem nearly halved the incidence of clinically significant arrhythmias (17/167 [10%] vs. 31/163 [19%], P = .02). The 2 groups did not differ in the incidence of other major postoperative complications or overall duration or costs of hospitalization. No serious adverse effects caused by diltiazem were seen. CONCLUSIONS: After major thoracic operations, prophylactic diltiazem reduced the incidence of clinically significant atrial arrhythmias in patients considered at high risk for this complication. VL - 120 IS - 4 ER - TY - JOUR T1 -

 

Is a synergistic 'cross-talk' among microbial and host-derived agonists the main cause of tissue and organ injury in post-infectious and inflammatory sequelae?: Facts, paradoxes, and myths (a view point)

JF - Pathogenesis: the journal of mechanisms in disease processes Y1 - 2000 A1 - Isaac Ginsburg VL - 1 IS - 4 ER - TY - JOUR T1 -

Cheminform abstract: novel anthraquinone derivatives with redox-active functional groups capable of producing free radicals by metabolism: are free radicals essential for cytotoxicity?

JF - ChemInform Y1 - 2000 A1 - Dinorah Barasch A1 - Omer Zipori A1 - Israel Ringel A1 - Isaac Ginsburg A1 - Amram Samuni A1 - Jehoshua Katzhendler AB - ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a Full Text option. The original article is trackable via the References option. VL - 31 IS - 6 ER - TY - JOUR T1 -

 

 

Are “Old” Pioneering Papers Passé?

JF - Clinical Infectious Diseases Y1 - 2000 A1 - Isaac Ginsburg AB - SIR—I have recently read with much interest a paper by Taylor et al. entitled “Staging the Baboon Response to Group A Streptococci Administrated Intramuscularly: Descriptive Study of the Clinical Symptoms and Clinical Chemical Response Patterns” in Clinical Infectious Diseases [1]. While reading through the paper, it became apparent to me that articles published since 1959, which had described in great detail the pathophysiology of group A streptococcal injury (animal models), had not been cited in this article [2–7]. One review had already covered, in detail, many of the aspects related to your article [2], and had described a steep rise in glutamic oxaloacetic transaminase levels, sorbitol dehydro-genase (SOD), and in total lipids in animals injected with extracellular products [6]. In addition, Taylor et al. cite a study (reference 48) on theta toxin. Why not cite studies that show the effects of streptolysins S and O? Furthermore, the possible effects of streptolysin O (reference 52) and cysteine proteinase (reference 53) are mentioned. I would also like to note, for the interest of the readers, a paper by Ginsburg [8] that had shown that tumor cells could be killed and disintegrated, in a synergistic manner, by combining streptolysins S with a proteinase. The cysteine proteinase employed was isolated from streptococci and kindly supplied by Dr. Elliot from the Rockefeller Institute (New York City). Moreover, I would like to draw the attention of the authors to a more recent publication that has discussed in great detail synergistic mechanisms of cell injury. I refer to a review by Ginsburg and Kohen [9]. It is of great concern that the avoidance of citations of “old” and pioneering publications has assumed epidemic dimensions, especially among younger investigators. Today, although without abstracts, MEDLINE already offers citations from 1960 and later; however, a search for “older and obsolete” literature necessitates a review of the Index Medicus. This apparently might be too cumbersome for those who tend to read only titles and abstracts and not the full texts of articles. This dangerous trend in science is self-defeating, unscholarly, unacceptable, and also unethical. Unfortunately, this is how basic observations and ideas are “lost and buried for good.” The phrase “sic transit gloria mundi” is very appropriate. It is even more disturbing that the learned referees of the paper by Taylor et al., who have been expected to be knowledgeable of the older literature on streptococci, have failed to draw their attention to the existence of such “obsolete” and apparently unimportant publications. Unfortunately this is how basic observations are “rediscovered,” leading to the suffocation of the literature with “novel,” but redundant information. I shall greatly appreciate receiving your comments regarding these issues and am also looking forward to learn what might be the future policies of the editorial board of the journal regarding strategies taken to better cope with lack of appropriate citations to support scientific publications. VL - 31 IS - 1 ER - TY - JOUR T1 -

 

The biology of leukocyte-mediated proteolysis

JF - Journal of Leukocyte Biology Y1 - 1999 A1 - Isaac Ginsburg AB - Comment on The cell biology of leukocyte-mediated proteolysis. [J Leukoc Biol. 1999] VL - 66 IS - 6 ER - TY - JOUR T1 -

Signal-averaged P-wave duration does not predict atrial fibrillation after thoracic surgery

JF - Anesthesiology Y1 - 1999 A1 - D. Amar A1 - N. Roistacher A1 - H. Zhang A1 - MS Baum A1 - Isaac Ginsburg A1 - JS Steinberg AB - BACKGROUND: Atrial fibrillation (AF) is the most common dysrhythmia seen early after major thoracic surgery but occurs infrequently after minor thoracic or other operations. A prolonged signal-averaged P-wave duration (SAPWD) has been shown to be an independent predictor of AF after cardiac surgery. The authors sought to determine whether a prolonged SAPWD alone or in combination with clinical or echocardiographic correlates predicts AF after elective noncardiac thoracic surgery. METHODS: Of the 250 patients enrolled, 228 were included in the final analysis. Preoperative SAPWD was obtained in 155 patients who had major thoracic surgery and in 73 patients undergoing minor thoracic or other operations who served as comparison control subjects. The SAPWD was recorded from three orthogonal leads using a sinus P-wave template. The filtered vector composite was used to measure total P-wave duration. Clinical, surgical, and echocardiographic parameters were collected and patients followed for 30 days after surgery for the development of symptomatic AF. RESULTS: Symptomatic AF developed in 18 of 155 (12%) patients undergoing major thoracic surgery and in 1 of 73 (1%) patients having minor thoracic or abdominal surgery, most commonly 2 or 3 days after surgery. In comparison with similar patients undergoing major thoracic surgery without AF, those who developed AF were older (66+/-8 vs. 62+/-10 yr; P = 0.04) but did not differ in SAPWD (145+/-17 vs. 147+/-16, ms) in standard electrocardiographic P-wave duration (105+/-7 vs. 107+/-10 mns), incidence of left-ventricular hypertrophy on 12-lead electrocardiography, male sex, history of hypertension, diabetes, or coronary heart disease. Thoracic-surgery patients at risk for postoperative AF did not differ from all other patients at low risk for AF in clinical or SAPWD parameters. CONCLUSIONS: Under the conditions of this study, SAPWD did not differentiate patients who did or did not develop AF after noncardiac thoracic surgery, and therefore its measurement cannot be recommended for the routine evaluation of these patients. Older age continues to be a risk factor for AF after thoracic surgery. VL - 91 IS - 1 ER - TY - JOUR T1 -

Hemolysis of human red blood cells induced by the combination of 

diethyldithiocarbamate (DDC) and divalent metals: Modulation by 

anaerobiosis, certain antioxidants and oxidants

JF - Free Radical Research Y1 - 1999 A1 - Isaac Ginsburg A1 - M. Sadovnic A1 - James Varani A1 - O. Tirosh A1 - Ron Kohen AB - The objective of the present communication is to describe the role played by combinations between diethydithiocarbamate (DDC) and divalent metals in hemolysis of human RBC. RBC which had been treated with DDC (10-50 microM) were moderately hemolyzed (about 50%) upon the addition of subtoxic amounts of Cu2+ (50 microM). However, a much stronger and a faster hemolysis occurred either if mixtures of RBC-DDC were immediately treated either by Co2+ (50 microM) or by a premixture of Cu2+ and Co2+ (Cu:Co) (50 microM). While Fe2+ and Ni2+, at 50 microM, initiated 30-50% hemolysis when combined with DDC (50 microM), on a molar basis, Cd2+ was at least 50 fold more efficient than any of the other metals in the initiation of hemolysis by DDC. On the other hand, neither Mn2+ nor Zn2+, had any hemolysis-initiating effects. Co2+ was the only metal which totally blocked hemolysis if added to DDC prior to the addition of the other metals. Hemolysis by mixtures of DDC + (Cu:Co) was strongly inhibited by anaerobiosis (flushing with nitrogen gas), by the reducing agents glutathione, N-acetyl cysteine, mercaptosuccinate, ascorbate, TEMPO, and alpha-tocopherol, by the PLA2 inhibitorbromophenacylbromide (BrPACBr), by tetracycline as well as by phosphatidyl choline, cholesterol and by trypan blue. However, TEMPO, BrPACBr and PC were the only agents which inhibited hemolysis induced by DDC: Cd2+ complexes. On the other hand, none of the classical scavengers of reactive oxygen species (ROS) employed e.g dimethylthiourea, catalase, histidine, mannitol, sodium benzoate, nor the metal chelators desferal and phenanthroline, had any appreciable inhibitory effects on hemolysis induced by DDC + (Cu:Co). DDC oxidized by H2O2 lost its capacity to act in concert either with Cu2+ or with Cd2+ to hemolyze RBC. While either heating RBC to temperatures greater than 37 degrees C or exposure of the cells to glucose-oxidase-generated peroxide diminished their susceptibility to hemolysis, exposure to the peroxyl radical from AAPH, enhanced hemolysis by DDC + (Cu:Co). The cyclovoltammetry patterns of DDC were drastically changed either by Cu2+, Co2+ or by Cd2+ suggesting a strong interaction of the metals with DDC. Also, while the absorbance spectrum of DDC at 280 nm was decreased by 50% either by Co2+, Cd2+ or by H2O2, a 90% reduction in absorbance occurred if DDC + H2O2 mixtures were treated either by Cu2+ or by Co2+, but not by Cd2+. Taken together, it is suggested that DDC-metal chelates can induce hemolysis by affecting the stability and the integrity of the RBC membrane, and possibly also of the cytoskeleton and the role played by reducing agents as inhibitors might be related to their ability to deplete oxygen which is also supported by the inhibitory effects of anaeobiosis. VL - 31 IS - 2 ER - TY - JOUR T1 -

Novel anthraquinone derivatives with redox-active functional groups capable of producing free radicals by metabolism: are free radicals essential for cytotoxicity?

JF - European Journal of Medicinal Chemistry Y1 - 1999 A1 - D. Barasch A1 - O. Zipori A1 - I. Ringel A1 - Isaac Ginsburg A1 - A. Samuni A1 - J. Katzhendler AB - The mode of action of antitumour anthraquinone derivatives (i.e. mitoxantrone) is not clearly established yet. It includes, among others, intercalation and binding to DNA, bioreduction and aerobic redox cycling. A series of anthraquinone derivatives, with potentially bioreducible groups sited in the side chain, have been synthesized and biologically evaluated. Their redox and cytotoxic activities were screened. Derivatives which bear a 2-(dimethylamino)ethylamino substituent, known to confer high DNA affinity, demonstrated cytotoxicity but not redox activity (beside the anthraquinone reduction). Conversely, derivatives which showed redox activity were not cytotoxic toward the P388 cell line. The results suggest that bioreduction is not the main mode of action in the cytotoxicity of anthraquinones. VL - 34 IS - 7-8 ER - TY - JOUR T1 -

Antibacterial synergistic effect of chlorhexidine and hydrogen peroxide against Streptococcus sobrinus, Streptococcus faecalis and Staphylococcus aureus

JF - Journal of Oral Rehabilitation Y1 - 1999 A1 - D. Steinberg A1 - I. Heling A1 - I. Daniel A1 - Isaac Ginsburg AB - Chlorhexidine (CHX) and Hydrogen peroxide (HP) are potent antibacterial agents that are used in controlling dental plaque. However, both agents bear undesired side-effects. We have tested the hypothesis that an antibacterial synergistic effect can occur between the two agents against Streptococcus sobrinus, Streptococcus faecalis and Staphylococcus aureus. We have found that at several combinations of HP and CHX an antibacterial synergistic effect does occur, while at other combinations a on-significant synergism was noticed. No antagonism between the two agents was found in our experimental system. It can be postulated that the mechanism of this synergistic effect is via alteration of the bacterial cell-surface by CHX thereby allowing for an increased amount of HP to penetrate and to react with the intercellular organelles of the bacteria. These results suggest that CHX and HP can be of use in controlling the dental plaque in the oral cavity. VL - 26 IS - 2 ER - TY - JOUR T1 -

PADMA-28, a traditional tibetan herbal preparation inhibits the respiratory burst in human neutrophils, the killing of epithelial cells by mixtures of oxidants and pro-inflammatory agonists and peroxidation of lipids

JF - Inflammopharmacology Y1 - 1999 A1 - Isaac Ginsburg A1 - Milu Sadovnik A1 - S Sallon A1 - I Milo-Goldzweig A1 - R Mechoulam A1 - A Breuer A1 - D Gibbs A1 - James Varani A1 - S Roberts A1 - E Cleator A1 - N Singh AB - Both aqueous and methanolic fractions derived from the Tibetan preparation PADMA-28 (a mixture of 22 plants) used as an anti-atherosclerotic agent, and which is non-cytolytic to a variety of mammalian cells, were found to strongly inhibit (1) the killing of epithelial cells in culture induced by 'cocktails' comprising oxidants, membrane perforating agents and proteinases; (2) the generation of luminol-dependent chemiluminescence in human neutrophils stimulated by opsonized bacteria; (3) the peroxidation of intralipid (a preparation rich in phopholipids) induced in the presence of copper; and (4) the activity of neutrophil elastase. It is proposed that PADMA-28 might prove beneficial for the prevention of cell damage induced by synergism among pro-inflammatory agonists which is central in the initiation of tissue destruction in inflammatory and infectious conditions. VL - 7 IS - 1 ER - TY - JOUR T1 -

Multi-drug strategies are necessary to inhibit the synergistic mechanism causing tissue damage and organ failure in post infectious sequelae

JF - Inflammopharmacology Y1 - 1999 A1 - Isaac Ginsburg AB - The paper discusses the principal evidence that supports the concept that cell and tissue injury in infectious and post-infectious and inflammatory sequelae might involve a deleterious synergistic interaction among microbial- and host-derived pro-inflammatory agonists. Experimental models had proposed that a rapid cell and tissue injury might be induced by combinations among subtoxic amounts of three major groups of agonists generated both by microorganisms and by the host's own defense systems. These include: (1) oxidants: Superoxide, H(2)O(2), OH', oxidants generated by xanthine-xanthine-oxidase, ROO; HOC1, NO, OONO'-, (2) the membrane-injuring and perforating agents, microbial hemolysins, phospholipases A(2) and C, lysophosphatides, bactericidal cationic proteins, fatty acids, bile salts and the attack complex of complement a, certain xenobics and (3) the highly cationic proteinases, elastase and cathepsin G, as well as collagenase, plasmin, trypsin and a variety of microbial proteinases. Cell killing by combinations among the various agonists also results in the release of membrane-associated arachidonate and metabolites. Cell damage might be further enhanced by certain cytokines either acting directly on targets or through their capacity to prime phagocytes to generate excessive amounts of oxidants. The microbial cell wall components, lipoteichoic acid (LTA), lipopolysaccharides (LPS) and peptidoglycan (PPG), released following bacteriolysis, induced either by cationic proteins from neutrophils and eosinophils or by beta lactam antibiotics, are potent activators of macrophages which can release oxidants, cytolytic cytokines and NO. The microbial cell wall components can also activate the cascades of coagulation, complement and fibrinolysis. All these cascades might further synergize with microbial toxins and metabolites and with phagocyte-derived agonsits to amplify tissue damage and to induce septic shock, multiple organ failure, 'flesh-eating' syndromes, etc. The long persistence of non-biodegradable bacterial cell wall components within activated macrophages in granulomatous inflammation might be the result of the inactivation by oxidants and proteinases of bacterial autolytic wall enzymes (muramidases). The unsuccessful attempts in recent clinical trials to prevent septic shock by the administration of single antagonists is disconcerting. It does suggest however that, since tissue damage in post-infectious syndromes is most probably the end result of synergistic interactions among a multiplicity of agents, only agents which might depress bacteriolysis in vivo and 'cocktails' of appropriate antagonists, but not single antagonists, if administered at the early phases of infection especially to patients at high risk, might help to control the development of post-infectious syndromes. However, the use of adequate predictive markers for sepsis and other post-infectious complications is highly desirable. Although it is conceivable that anti-inflammatory strategies might also be counter-productive as they might act as 'double-edge swords', intensive investigations to devise combination therapies are warranted. The present review also lists the major anti-inflammatory agents and strategies and combinations among them which have been proposed in the last few years for clinical treatments of sepsis and other post-infectious complications. VL - 7 IS - 3 ER - TY - JOUR T1 -

Is streptolysin S of group A streptococci a virulence factor?

JF - APMIS Y1 - 1999 A1 - Isaac Ginsburg AB - The possible role played by streptolysin S (SLS) of group A streptococci in the pathophysiology of streptococcal infections and in post-streptococcal sequelae is discussed. The following properties of SLS justify its definition as a distinct virulence factor: 1) its presence on the streptococcus surface in a cell-bound form, 2) its continuous and prolonged synthesis by resting streptococci, 3) its non-immunogenicity, 4) its extractability by serum proteins (albumin, alpha lipoprotein), 5) its ability to become transferred directly to target cells while being protected from inhibitory agents in the milieu of inflammation, 6) its ability to bore holes in the membrane phospholipids in a large variety of mammalian cells, 7) its ability to synergize with oxidants, proteolytic enzymes, and with additional host-derived proinflammatory agonists, and 8) its absence in streptococcal mutants associated with a lower pathogenicity for animals. Because tissue damage in streptococcal and post-streptococcal sequelae might be the end result of a distinct synergism between streptococcal and host-derived proinflammatory agonists it is proposed that only cocktails of anti-inflammatory agents including distinct inhibitors of SLS (phospholipids), gamma globulin, inhibitors of reactive oxygen species, proteinases, cationic proteins cytokines etc., will be effective in inhibiting the multiple synergistic interactions which lead to fasciitis, myositis and the flesh-eating syndromes, and often develop into sepsis, septic shock and multiple organ failure. The creation of mutants deficient in SLS and in proteases will help shed light on the specific role played by SLS in the virulence of group A hemolytic streptococci. VL - 107 IS - 12 ER - TY - JOUR T1 -

"Cross-talk" among a multiplicity of pro-inflammatory agents: main cause of tissue damage in pulmonary inflammation?

JF - European Respiratory Journal Y1 - 1999 A1 - Isaac Ginsburg AB - Comment on Proteolytic enzymes and airway diseases. [Eur Respir J. 1998] Neutrophil serine proteinases and defensins in chronic obstructive pulmonary disease: effects on pulmonary epithelium. [Eur Respir J. 1998] To the Editor: I have recently read with much interest two excellent reports in the European Respiratory Journal which discussed the role of neutrophil proteinases and defensins in chronic obstructive pulmonary disease [1] and in airway diseases [2]. Reading through these articles, it was surprising not to find any considerations of a major aspect related to the elucidation of the possible mechanisms of tissue damage in the lungs during inflammation. I refer to extensive studies from several laboratories which had proposed that tissue damage in inflammatory and infectious processes may primarily be the result of a synergistic "cross talk" among a multiplicity of pro-inflammatory agents (a multi-component system) [3, 4]. A series of publications [5±14] have shown that a severe and rapid membrane injury (necrosis) could be initiated in mammalian cells by a synergism among subtoxic concen- trations of three major groups of agonists. These included a) oxidants (H2O2, peroxyl radical, oxidants generated by xanthine-xanthine-oxidase, NO, HOCl, OONO-), b) mem- brane -perforating agents (microbial haemolysins/phospho- lipases A2 and C, lysophosphatides, free fatty acids, cationic proteins, histone [9] and defensins [5], and c) highly cationic proteolytic enzymes, (elastase, cathepsin G) [3, 4, 12]. These synergistic cytotoxic effects can be further amplified by certain cytokines. Furthermore, combinations of oxidants and elastase have also been shown to synergize to cause severe lung damage in animal models [6±10]. It has also been proposed that a deleterious synergism among microbial and host-derived pro-inflammatory agonists may frequently contribute to tissue injury in many infectious and post- infection complications [3, 4]. A notable example is, sepsis and the "flesh-eating" syndrome caused by highly toxigenic and invasive bacteria. Other studies had also shown that subtoxic amounts of the membrane-active xenobiotics, ethanol, methanol, n-butanol and the pesticide linden [13], could also synergize with subtoxic concentrations of peroxide, proteinases and cationic agents to amplify the damage to endothelial cells in culture. The results with the xenobiotics are of especial interest and concern to pulmonologists as these volatile agents may be inhaled and might then synergize with oxidants, proteinases and cationic proteins released either by accumulating neu- trophils or by activated lung macrophages to cause damage to both epithelial and endothelial cells. It has also been documented that ˜-lactam antibiotics and a large variety of cationic agents including, elastase, cath- epsin G, defensins, lysozyme, myeloperoxidase, spermine, spermidine, histones, polymyxin B and chlorhexidine are all capable of activating the autolytic wall enzymes (murami- dases) in bacteria leading to bacteriolysis [14]. Bacteriolysis at least in Gram-positive bacteria induced either by ˜- lactams or by cationic agents can, however, be strongly inhibited by sulphated polyanions presumably by inactivat- ing the autolytic wall enzymes responsible for breaking down the rigid cell wall. It is accepted that the massive release widely of bacterial wall components (lipopolysac- charide, lipoteichoic acid (LTA), peptidoglycan), in vivo, can activate macrophages to release cytotoxic cytokines, NO and also to activate the complement and coagulation cascades leading to sepsis, systemic inflammatory response syndrome (SIRS), multiple organ disfunction syndrome (MODS) and multiple organ failure (MOF) [15]. Today there are controversial opinions and hot debates regarding the approaches to treat sepsis, adult respiratory distress syndrome (ARDS) and additional post-infectious and inflammatory sequelae [15]. Unfortunately, the exclu- sive use of single antagonists to treat these syndromes has yielded poor results. Such failures may principally be due to, a) the lack of adequate and rapid tests to predict the onset of such complications so that treatment of patients usually starts too late, and b) a lack of sufficient awareness that fighting the deleterious effects caused by synergistic cytotoxic mechan- isms necessitates the use not of single antagonists but of cocktails comprised of a multiplicity of anti-inflammatory agents. Hopefully, a wider recognition of synergism concept of cellular injury [3, 4, 11±13] might offer a new and more realistic approach to this complex and still unsolved clinical problem. I. Ginsburg Dept of Oral Biology, Hebrew University - Hadassah Faculty of Dental Medicine, Jerusalem, Israel. Fax: 972 26758583. VL - 14 IS - 2 ER - TY - JOUR T1 -

Can we learn from the pathogenetic strategies of group A hemolytic streptococci how tissues are injured and organs fail in post-infectious and inflammatory sequelae?

JF - FEMS Immunology & Medical Microbiology Y1 - 1999 A1 - Isaac Ginsburg A1 - Peter A Ward A1 - James Varani AB - The purpose of this review-hypothesis is to discuss the literature which had proposed the concept that the mechanisms by which infectious and inflammatory processes induce cell and tissue injury, in vivo, might paradoxically involve a deleterious synergistic ‘cross-talk’, among microbial- and host-derived pro-inflammatory agonists. This argument is based on studies of the mechanisms of tissue damage caused by catalase-negative group A hemolytic streptococci and also on a large body of evidence describing synergistic interactions among a multiplicity of agonists leading to cell and tissue damage in inflammatory and infectious processes. A very rapid cell damage (necrosis), accompanied by the release of large amounts of arachidonic acid and metabolites, could be induced when subtoxic amounts of oxidants (superoxide, oxidants generated by xanthine-xanthine oxidase, HOCl, NO), synergized with subtoxic amounts of a large series of membrane-perforating agents (streptococcal and other bacterial-derived hemolysins, phospholipases A2 and C, lysophosphatides, cationic proteins, fatty acids, xenobiotics, the attack complex of complement and certain cytokines). Subtoxic amounts of proteinases (elastase, cathepsin G, plasmin, trypsin) very dramatically further enhanced cell damage induced by combinations between oxidants and the membrane perforators. Thus, irrespective of the source of agonists, whether derived from microorganisms or from the hosts, a triad comprised of an oxidant, a membrane perforator, and a proteinase constitutes a potent cytolytic cocktail the activity of which may be further enhanced by certain cytokines. The role played by non-biodegradable microbial cell wall components (lipopolysaccharide, lipoteichoic acid, peptidoglycan) released following polycation- and antibiotic-induced bacteriolysis in the activation of macrophages to release oxidants, cytolytic cytokines and NO is also discussed in relation to the pathophysiology of granulomatous inflammation and sepsis. The recent failures to prevent septic shock by the administration of only single antagonists is disconcerting. It suggests, however, that since tissue damage in post-infectious syndromes is caused by synergistic interactions among a multiplicity of agents, only cocktails of appropriate antagonists, if administered at the early phase of infection and to patients at high risk, might prevent the development of post-infectious syndromes. VL - 25 IS - 4 ER - TY - JOUR T1 -

Persistent alterations of the autonomic nervous system after noncardiac surgery

JF - Anesthesiology Y1 - 1998 A1 - D. Amar A1 - M. Fleisher A1 - C.B. Pantuck A1 - H. Shamoon A1 - H. Zhang A1 - N. Roistacher A1 - D.H.Y. Leung A1 - Isaac Ginsburg A1 - R.M. Smiley AB - BACKGROUND. Changes in the sympathetic nervous system may be a cause of postoperative cardiovascular complications. The authors hypothesized that changes in both beta-adrenergic receptor (betaAR) function (as assessed in lymphocytes) and in sympathetic activity (assessed by plasma catecholamines and by heart rate variability [HRV] measurements obtained from Holter recordings) occur after operation. METHODS: The HRV parameters were measured in 28 patients having thoracotomy (n = 14) or laparotomy (n = 14) before and for as long as 6 days after operation. Transthoracic echocardiography was performed before and on postoperative day 2. Lymphocytes were also isolated from blood obtained before anesthesia and again on postoperative days 1, 2, 3, and 5 (or 6). They were used to examine betaAR number (Bmax) and cyclic adenosine monophosphate (cAMP) production after stimulation with isoproterenol and prostaglandin E1. In addition, plasma epinephrine, norepinephrine, and cortisol concentrations were determined at similar intervals. RESULTS: After abdominal and thoracic surgery, most time and all frequency indices of HRV decreased significantly, as did Bmax and basal and isoproterenol-stimulated cAMP production. The decrements in HRV correlated with those of Bmax and isoproterenol-stimulated cAMP throughout the first postoperative week and inversely correlated with the increase in heart rate. Plasma catecholamine concentrations did not change significantly from baseline values, but plasma cortisol levels did increase after operation in both groups. Left ventricular ejection fraction was normal in both groups and unaffected by surgery. CONCLUSIONS: Persistent downregulation and desensitization of the lymphocyte betaAR/adenylyl cyclase system correlated with decrements in time and frequency domain indices of HRV throughout the first week after major abdominal or thoracic surgery. These physiologic alterations suggest the continued presence of adaptive autonomic regulatory mechanisms and may explain why the at-risk period after major surgery appears to be about 1 week or more. VL - 89 IS - 1 ER - TY - JOUR T1 -

Tissue injury in neutrophilic inflammation

JF - Inflammation Research Y1 - 1998 A1 - Isaac Ginsburg AB - Comment on Tissue injury in neutrophilic inflammation. [Inflamm Res. 1997] VL - 47 IS - 6 ER - TY - JOUR T1 -

Gamma globulin, Evan's blue, aprotinin A PLA2 inhibitor, tetracycline and antioxidants protect epithelial cells against damage induced by synergism among streptococcal hemolysins, oxidants and proteinases

JF - FEMS Immunology and Medical Microbiology Y1 - 1998 A1 - Isaac Ginsburg A1 - Milu Sadovnik AB - An in vitro model was employed to study the potential role of streptococcal extra-cellular products, rich in streptolysin O, in cellular injury as related to streptococcal infections and post-streptococcal sequelae. Extra-cellular products (EXPA) rich in streptolysin O were isolated from type 4, group A hemolytic streptococci grown in a chemostat, in a synthetic medium. EXPA induced moderate cytopathogenic changes in monkey kidney epithelial cells and in rat heart cells pre-labeled with 3H-arachidonate. However very strong toxic effects were induced when EXP was combined with oxidants (glucose oxides generated H2O2, AAPH-induced peroxyl radical (ROO.), NO generated by sodium nitroprusside) and proteinases (plasmin, trypsin). Cell killing was distinctly synergistic in nature. Cell damage induced by the multi-component cocktails was strongly inhibited either by micromolar amounts of gamma globulin, and Evan's blue which neutralized SLO activity, by tetracycline, trasylol (aprotinin), epsilon amino caproic acid and by soybean trypsin inhibitor, all proteinase inhibitors as well as by a non-penetrating PLA2 inhibitor A. The results suggest that fasciitis, myositis and sepsis resulting from infections with hemolytic streptococci might be caused by a coordinated 'cross-talk' among microbial, leukocyte and additional host-derived pro-inflammatory agents. Since attempts to prolong lives of septic patients by the exclusive administration of single antagonists invariably failed, it is proposed that the administration of 'cocktails' of putative inhibitors against major pro-inflammatory agonizes generated in inflammation and infection might protect against the deleterious effects caused by the biochemical and pharmacological cascades which are known to be activated in sepsis. VL - 22 IS - 3 ER - TY - JOUR T1 -

Mechanisms of neutrophil-induced parenchymal cell injury

JF - Journal of Leukocyte Biology Y1 - 1998 A1 - Isaac Ginsburg AB - I read with much interest the review article ‘‘Mechanisms of neutrophil-induced parenchymal cell injury’’(H. Jaeschke and C.W. Smith, J. Leukoc. Biol. 61, 647–653). As I read through the text it became apparent that very basic and relevant concepts as well as publications regarding the possible mecha- nisms by which phagocytes kill targets had not been included in the review. The authors rightfully write, ‘‘The question regarding the molecular mechanism of neutrophil-induced target cell injury is controversial.’’ Yet despite the common knowledge and understanding that the mechanisms of cell damage most probably involve an interaction among a multiplicity of agonists (a multicomponent system), the section, ‘‘Mechanisms of neutro- phil-induced parenchymal cell injury’’ had adopted an ex- tremely reductionist and oversimplified approach to the prob- lem. It considered (see Fig. 1) what seems to be the exclusive role of oxidants and proteinases as potential cell injuring agents, as if these are the sole noxious agents generated by activated phagocytes. Although I fully respect the prerogatives and choices by the authors to refer exclusively to hepatocytes and parenchymal cells and to select citations from the literature pertaining to these tissues in order to support their thesis, it is still intriguing why not a single word was mentioned about the obvious possibility that oxidants, proteinases, and additional agonists might perhaps act mainly in concert (synergize) to injure any cell type? To the best of our knowledge and experience in this field of research (see list of recommended literature), even a normal cell line, as well as some of the tumor cells tested in vitro by us and by others, which could not readily be killed by physiologi- cal amounts of oxidants (H2O2 ROO, HCIO, NO) alone, were nevertheless rapidly killed in a synergistic manner if the oxidants were combined with any of a long list of membrane- perforating agents. These included phospholipase A2, phospho- lipase C, lysophosphatides, fatty acids, microbial hemolysins, cationic peptides and proteins, bile salts, complement compo- nents, and xenobiotics such as ethanol, methanol, and lindane. The inclusion of proteinases (trypsin, plasmin, elastase chymotrypsin), together with oxidants and the membrane perforators, further significantly enhanced cellular damage. It is also of great interest and is perhaps paradoxical that microbial agents might also synergize with phagocyte-derived agonists, but in an adverse fashion, to injure host tissues. It is also important to consider that all these proinflammatory agonists might be simultaneously present in infectious and inflammatory sites. Our studies also suggested that the induction of a sublethal membrane injury abolished, to a large extent, the potent antioxidant defenses of the cells— a finding of great significance. The readers of the Journal of Leukocyte Biology might be interested in a series of publications dealing with the ‘‘syner- gism’’ concept of cellular injury as related to infectious and inflammatory conditions, which have been published since 1986 (see list of recommended literature). An invited overview by Ginsburg and Kohen [8] undertook to discuss, in great detail, those papers that described the role of synergism in cellular injury. Unfortunately and enigmatically, publications that have described the ‘‘synergism concept’’ of cellular injury published since 1986 are hardly ever cited. If the synergism concept of cellular injury is logical and conforms with the current knowledge in the field, publications describing this phenom- enon should be quoted. If on the other hand these ideas are extreme, bizarre, and scientifically unacceptable, such papers should be discussed and challenged properly and even ridi- culed. However, it is totally unacceptable that such publica- tions be simply ignored. Approaching the third millennium, the readers of scientific journals deserve not an oversimplified approach to complicated scientific issues, but more realistic, integrated, and updated appraisals of the literature even if these might not always fully conform with the investigator’s own concepts or with the prevailing paradoxes, dogmas, cliches, and myths. It is also very surprising, and of great concern, why the referees of the papers did not bring any of these publications and concepts to the attention of the authors. After all, the main task of the referees and the editorial board is to criticize the validity and novelty of investigations brought to their attention and to strongly instruct negligent authors to give proper credit to relevant papers and concepts in their field of research. It is regrettable that this has not happened. Unfortunately, this is how, for the sake of brevity and a reductionist approach to the solution of complex biological phenomena, very basic and pioneering investigations and ‘‘novel’’ concepts may be simply ignored and buried for good. It is obvious that the ones who might suffer most from such an approach to the compilation of reviews and papers are the investigators, the readers, and perhaps most importantly, the credibility of journals at large. I shall greatly appreciate receiving comments and sugges- tions about these matters. VL - 63 IS - 4 ER - TY - JOUR T1 -

Could synergistic interactions among reactive oxygen species, proteinases, membrane-perforating enzymes, hydrolases, microbial hemolysins and cytokines be the main cause of tissue damage in infectious and inflammatory conditions?

JF - Medical Hypotheses Y1 - 1998 A1 - Isaac Ginsburg AB - The mechanisms of cellular damage caused by infectious and inflammatory processes are complex and are still not fully understood. There is, however, a consensus that reactive oxygen species (ROS) generated by phagocytes migrating to injured tissues might be the main agents responsible for cellular damage in inflammatory processes. However, because both activated phagocytes and catalase-negative, peroxide-producing, toxigenic bacteria (Streptococci, Clostridiae) secrete a near-identical array of proinflammatory agonists, including reactive oxygen species (ROS), and because these microbial species might kill their targets by a synergism among several of their secreted enzymes (a multicomponent system), we postulated that activated phagocytes might also function in the same way. Using radiolabeled targets, in culture, we demonstrated that subtoxic amounts of a variety of oxidants (H2O2, radicals produced by xanthine-xanthine-oxidase, peroxyl radical, NO) acted synergistically with subtoxic amounts of a large series of membrane-perforating agents (microbial hemolysins, phospholipases, fatty acids, cationic proteins, proteinases, bile salts, the attack complex of complement, the xenobiotics, lindane, ethanol, methanol) to kill cells in culture and to release large amounts of arachidonic acid and metabolites. Membrane perforators might act primarily to overcome the potent antioxidant systems present in all mammalian cells and scavengers of ROS and inhibitors of the additional agonists might act to abolish the synergism among ROS and the membrane-damaging agents. It is also proposed that protection against tissue damage in vivo should also include 'cocktails' of appropriate antagonists. It is enigmatic that those publications which do describe both in-vitro and in-vivo models proposing that a synergism among a multiplicity of agonists might truly represent the mechanisms by which tissues are injured, in vivo, are hardly ever quoted in the current literature. VL - 51 IS - 4 ER - TY - JOUR T1 -

A comparison between the effects of meloxicam and other nsaids on the production of oxyradicals by human polymorphonuclear leucocytes

JF - Inflammopharmacology Y1 - 1997 A1 - K. D. Rainsford A1 - Isaac Ginsburg A1 - S. J. Gadd AB - Some non-steroidal anti-inflammatory drugs (NSAIDs) inhibit the production or actions of oxygen radicals generated by polymorphonuclear leucocytes (PMNs); this mechanism may contribute towards their anti-inflammatory activity. In the present study, the effects of a new enolcarboxamide NSAID, meloxicam, on oxyradical production by human PMNs exposed to various stimuli in vitro were compared with those of other standard NSAIDs. The various stimuli employed were intended to mimic the likely synergies which occur with cytokines and bacterial production (e.g. f-met-leu-phe (fMLP) peptide) in inflamed tissues and to give an insight into the site and mechanism of action of meloxicam and related drugs on the cellular processes involved in oxyradical generation. The results show that meloxicam is a potent inhibitor of oxyradical production at drug concentrations comparable with those encountered during therapy. Its mechanism of action appears similar to that of other enolcarboxamides and, while relatively complex, involves effects which are stimulus dependent and myeloperoxidase sensitive. They probably do not involve inhibition of fMLP-Gi protein receptor activation but may involve tumour necrosis factor-⇌ post-receptor activation. Enolcarboxamides have variable effects on phorbol myristate acetate-protein kinase C3-mediated oxyradical production. VL - 5 IS - 1 ER - TY - JOUR T1 -

Diethyldithiocarbamate and nitric oxide synergize with oxidants and with membrane-damaging agents to injure mammalian cells.

JF - Free Radical Research Y1 - 1997 A1 - Isaac Ginsburg A1 - S. Yedgar A1 - James Varani AB - The effect of diethyldithiocarbamate (DDC) and sodium nitroprusside (SNP) on the killing of endothelial cells and on the release of arachidonate by mixtures of oxidants and membrane-damaging agents was studied in a tissue culture model employing bovine aortic endothelial cells labeled either with 51Chromium or 3arachidonic acid. While exposure to low, subtoxic concentrations of oxidants (reagent H2O2, glucose-oxidase generated peroxide, xanthine xanthine oxidase, AAPH-generated peroxyl radical, menadione-generated oxidants) did not result either in cell death or in the loss of membrane-associated arachidonic acid, the addition of subtoxic amounts of a variety of membrane-damaging agents (streptolysin S, PLA2, histone, taurocholate, wheatgerm agglutinin) resulted in a synergistic cell death. However, no significant amounts of arachidonate were released unless proteinases were also present. The addition to these reaction mixtures of subtoxic amounts of DDC (an SOD inhibitor and a copper chelator) not only very markedly enhanced cell death but also resulted in the release of large amounts of arachidonate (in the complete absence of added proteinases). Furthermore, the inclusion in DDC-containing reaction mixtures of subtoxic amounts of SNP, a generator of NO, further enhanced, in a synergistic manner, both cell killing and the release of arachidonate. Cell killing and the release of arachidonate induced by the DDC and SNP-containing mixtures of agonists were strongly inhibited by catalase, glutathione, N-acetyl cysteine, vitamin A, and by a nonpenetrating PLA2 inhibitor as well as by tetracyclines. A partial inhibition of cell killing was also obtained by 1,10-phenanthroline and by antimycin. It is suggested that DDC might amplify cell damage by forming intracellular, loosely-bound complexes with copper and probably also by depleting antioxidant thiols. It is also suggested that "cocktails" containing oxidants, membrane-damaging agents, DDC, and SNP might be beneficial for killing of tumor cells in vivo and for the assessment of the toxicity of xenobiotics in vitro. VL - 27 IS - 2 ER - TY - JOUR T1 -

Measurement of croton oil induced rabbit ear swelling and evaluation of anti-inflammatory agents with a standard low pressure caliper

JF - Skin Research and Technology Y1 - 1996 A1 - V. Manny-Aframian A1 - A. Shafran A1 - A. Zlotogorski A1 - Isaac Ginsburg A1 - S. Dikstein AB - Background/airns: Carbobenzoxy-phenylalanyl-methionine (CBZ-Phe-Met), a known inhibitor of the chemotactic peptide N- formyl-methionyl-leucyl-phenylalanine (fMLP) in vitro, has not been evaluated as a topical anti-inflammatory agent in vivo. In order to measure the effect of CBZ-phe-met, one needs a repeat- able, quantitative, easily obtainable standard measurement of the edema formation. In this study, a caliper designed for measuring soft materials was used to evaluate the edema, in- duced by croton oil on rabbit ears, as well as the effects of CBZ- phe-met. Methods: The model used in this study was croton-induced in- flammation on rabbit ears. A caliper for measuring soft materials ( European standard DIN 863 part 3, manufactured by TESA Ltd., Renens, Switzerland) was used to evaluate the edema, which is part of the inflammatory effect . The action of CBZ-phe- met and two other anti-inflammatory agents; hydrocortisone and Na-ibuprofen, were compared. Results: CBZ-phe-met 1-5% was found to reduce the edema on rabbit ears induced by croton oil by 15 to 93%. 5% CBZ-phe- met was found to be as effective as 5% Na-ibuprofen and 0.1% hydrocortisone. Conclusion: The caliper for soft materials was found to be suit- able for measuring the edema induced by croton-oil, as well as the reducing edema due to anti-inflammatory treatment. It was also found that CBZ-phe-met is a potent topical anti-inflamma- tory agent in the croton-oil-induced inflammatory model. This may indicate a new approach in the treatment of inflammation. Key words: Soft material caliper - inflammation - N-formyl-me- thionyl-leucyl-phenylalanine (fMLP) - carbobenzoxy-phenylala- nyl-methionyl (CBZ-phe-met). VL - 2 IS - 3 ER - TY - PAT T1 -

Thionophosphate derivatives, process for their preparation and pharmaceutical compositions containing them

Y1 - 1996 A1 - Y. Barenholz A1 - Isaac Ginsburg A1 - J. Katzhendler A1 - Ron Kohen A1 - O. Tirosh AB - The invention relates to a compound of formula (I) in which X1 and X2 each independently represents an oxygen or nitrogen atom; p, m and n are each independently an integer of at least 2; R, R1 and R2 each independently represents a hydrogen atom; a halogen atom; an optionally substituted straight-chained or branched alkyl, alkenyl or alkynyl radical; a group R3O in which R3 is hydrogen atom, an optionally substituted straight-chained or branched alkyl, alkenyl or alkynyl radical; optionally substituted acyl or optionally substituted aryl or heteroaryl; a group R4O(O)C in which R4 is a hydrogen atom or an optionally substituted straight-chained or branched alkyl, alkenyl or alkynyl radical; a group -SR5 in which R5 is a hydrogen atom or an optionally substituted straight-chained or branched alkyl, alkenyl or alkynyl radical; a group -NR6R7 in which R6 and R7 each independently represents a hydrogen atom, an optionally substituted straight-chained or branched alkyl, alkenyl or alkynyl radical; optionally substituted acyl; or an optionally substituted phosphate ester group. The invention also relates to processes for the preparation of compounds of the formula and to pharmaceutical compositions containing the same. VL - WO 1996016663 A1 ER - TY - JOUR T1 -

Prevention of oxidative damage in fibroblast cell cultures and rat skin by positively-charged submicron emulsion of alpha-tocopherol

JF - European Journal of Pharmaceutics and Biopharmaceutics Y1 - 1996 A1 - Revital Ezra A1 - Shimon Benita A1 - Isaac Ginsburg A1 - Ron Kohen AB - An attempt was made to incorporate alpha-tocopherol in negatively and positively-charged submicron emulsions, with the aim of providing an effective topical preparation against skin oxidative damage. In cell culture toxicity experiments using human fibroblast it was shown that the positively-charged alpha-tocopherol emulsion did not exhibit any toxic effect despite the low dilution and respective high concentration used. Negatively and positively-charged submicron emulsions of alpha-tocopherol and their respective blank emulsions were topically applied to rats that were subjected to UVA irradiation under different experimental conditions. No difference was observed between the negatively and positively-charged alpha-tocopherol submicron emulsions regarding the rate of oxidation and peroxyl radical scavenging ability of skin homogenates and both were able to protect rat skin against oxidative stress. However, in a non-invasive evaluation of the lipid hydroperoxidation process in rat skin following exposure to UVA irradiation, the positively-charged alpha-tocopherol submicron emulsion elicited a significantly better protective effect than the corresponding negatively-charged emulsion. These results suggest that the positively-charged emulsion exhibits a more prolonged residence time in the uppermost layers of the skin than the negatively-charged emulsion. VL - 42 IS - 4 ER - TY - JOUR T1 -

Antioxidant properties of amidothionophosphates: novel antioxidant molecules

JF - Free Radical Biology and Medicine Y1 - 1996 A1 - O. Tirosh A1 - Y. Katzhendler A1 - Y. Barenholz A1 - Isaac Ginsburg A1 - Ron Kohen AB - This work describes the synthesis and characterization of a new family of antioxidants. The molecules have the same active group, but different oil-to-water and octanol-to-water partition coefficients due to different substituents. Three new molecules were synthesized based on the chemical structure of the primary amide attached to a thiophosphate group forming an amidothionophosphate. The amidothionophosphate molecules were exposed to the oxidative stress of hydrogen peroxide and sodium hypochlorite, and the chemical changes following the exposure were monitored by 31P NMR. The reaction constants with the reactive oxygen species hydroxyl radical and superoxide radical were also calculated and found to be 1.5 x 10(9) M-1s-1 and 8.1 x 10(2) M-1s-1, respectively. To elucidate the ability of amidothionophosphates to act as antioxidants in protecting lipids and proteins, we examined damage prevention in bovine serum albumin, egg phosphatidylcholine liposomes, and lipid emulsions following oxidative stress. Amidothionophosphate showed unique protection properties in these models. In contrast to other antioxidant molecules (ascorbic acid, cysteine, and alpha-tocopherol) the new group did not have any pro-oxidative effects as measured by oxygen consumption from buffer solutions containing amidothionophosphates and cupric sulfate as a source of redox-active metal ions. Amidothionophosphates reduced significantly and in a dose-dependent manner the oxidative burst in human neutrophils as measured by luminol-dependent chemiluminescence, and they also markedly depressed the killing of human fibroblasts by mixtures of glucose oxidase and streptolysin S. The toxicity of these molecules was tested by IP injection of doses up to 1000 mg/kg to white Sabra mice. No mortality was observed 30 d after administration of up to 500 mg/kg. VL - 20 IS - 3 ER - TY - JOUR T1 -

H2O2 renders cells accessible to lysis by exogenous phospholipase A2: a novel mechanism for cell damage in inflammatory processes.

JF - FEBS Letters Y1 - 1996 A1 - P. Dan A1 - D.W. Nitzan A1 - A. Dagan A1 - Isaac Ginsburg A1 - S. Yedgar AB - Phospholipase A2 (PLA2) and H2O2, secreted from activated inflammatory cells, play a central role in the tissue damage occurring in inflammatory processes. However, while exogenous PLA2 alone does not cause cell lysis, it readily does so when acting with H2O2. We have found that H2O2 degrades cell surface proteoglycans, thus rendering the membrane PL accessible to hydrolysis by exogenous PLA2. This novel mechanism introduces a role for cell surface proteoglycans in protection of cells from damage by pro-inflammatory agents, and may assign a central role for the combined action of H2O2 and PLA2 in inflammatory and bacteriocidal processes. VL - 383 IS - 1-2 ER - TY - JOUR T1 -

A novel approach to the assessment of toxicity of hexachlorocyclohexane (Lindane) and of certain organic solvents: Killing of cells in culture and the release of arachidonate by synergism among H2O2 membranedamaging agents histone and trypsin

JF - Journal of Basic and Applied Research Y1 - 1996 A1 - Isaac Ginsburg A1 - Douglas F. Gibbs A1 - Steven Tarapchak A1 - James Varani AB - A novel approach to the assessment of the toxicity of the chlorinated pesticide hexachlorocyclohexane (lindane) and the organic solvents methanol and w-butanol, employing endothelial cells in culture, is presented. This highly reproducible system involves the simultaneous treatment of [51Cr]. and [3H]arachidonic acid-labeled rat pulmonary endothelial cells with xenobiotics combined with glucose oxidase-generated H2O2, phospholipase c, streptolysin S, diethyldithiocarbamate (DDC), sodium nitroprusside (NP), histone, and trypsin. Such treatment leads to synergistic cell killing and the release of arachidonic acid (Ginsburg and Kohen, 1995b). Thus, subtoxic amounts of xenobiotics that failed to kill the cells became highly cytolytic when combined with the various mixtures of agonists. Cytotoxicity and the release of membrane lipids are strongly inhibited by catalase, by Mn2+, and by soybean trypsin inhibitor. The "synergism" concept of cellular toxicity is relevant, in particular, in infectious and inflammatory sites where phagocyte- and tissue-derived proinflammatory agonists are generated in large amounts as a result of cellular damage induced either by pathogenic microorganisms, by activated phagocytes, or by xenobiotics. This simple and inexpensive in vitro model of cellular cytotoxicity might supplement and even replace the more costly animal experimentations involved in the assessment of the toxicity and safety of newly designed drugs. VL - 9 IS - 3 ER - TY - JOUR T1 -

Control of inflammatory processes by cell-impermeable inhibitors of phospholipase A2

JF - Agents Actions Y1 - 1995 A1 - S. Yedgar A1 - P. Dan A1 - A. Dagan A1 - Isaac Ginsburg A1 - IS Lossos A1 - R. Breuer AB - Cell-impermeable inhibitors of phospholipase A2 were prepared by linking inhibiting molecules to macromolecular carriers which prevent the inhibitor's internalization. These preparations inhibit the release of oxygen reactive species from neutrophils and cell death induced by inflammatory agents, as well as bleomycin-induced lung injury. VL - 46 ER - TY - JOUR T1 -

Antioxidants inhibit ethanol-induced gastric injury in the rat. Role of manganese, glycine, and carotene

JF - Scandinavian Journal of Gastroenterology Y1 - 1995 A1 - M. Ligumsky A1 - M. Sestieri A1 - E. Okon A1 - Isaac Ginsburg AB - BACKGROUND: Oxygen-derived radicals are implicated in the pathogenesis of tissue damage and ulcerogenesis. This study aimed to examine the effect of manganese, glycine, and carotene, oxygen radical scavengers, on ethanol-induced gastric lesions in the rat and on ethanol cytotoxicity in epithelial cell culture. METHODS: MnCl2 + glycine (12.5-50 mg/rat) were injected subcutaneously up to 6 h before oral administration of 1 ml of 96% ethanol, and 0.5 ml carrot juice or beta-carotene was given orally 30 min before the ethanol. Mucosal injury was evaluated 1 h later by gross and microscopic scoring. The effect of Mn2+ and carrot juice was also tested in monolayers of radiolabeled epithelial cells exposed to H2O2 + ethanol injury as expressed by the extent of the isotope leakage. RESULTS: Mn2+ and glycine pretreatment dose-dependently reduced ethanol-induced gastric lesion formation. Protection was maximal when treatment was applied 4 h before the insult. Gross damage was also markedly prevented by pretreatment with carotenes and dimethylthiourea (DMTU, 75 mg/kg intraperitoneally) but not by allopurinol. Mixtures of subtoxic concentrations of ethanol and H2O2 were highly lethal for epithelial cell monolayers. In this model, cell death was markedly attenuated by catalase, DMTU, Mn2+, and carrot juice. CONCLUSIONS: Ethanol-induced gastric mucosal damage may involve generation of oxygen-derived radicals, independent of the xanthine oxidase system. By acting as oxygen radical scavengers, Mn2+, glycine, and carotenes, like catalase and DMTU, provide significant gastroprotection. VL - 30 IS - 9 ER - TY - JOUR T1 -

Synergistic effects among oxidants, membrane-damaging agents, fatty acids, proteinases, and xenobiotics: killing of epithelial cells and release of arachidonic acid

JF - Inflammation Y1 - 1995 A1 - Isaac Ginsburg A1 - Ron Kohen AB - The assumption that cellular injury induced in infectious and in inflammatory sites might be the result of a well-orchestrated, synergistic "cross-talk" among oxidants, membrane-damaging agents, proteinases, and xenobiotics was further investigated in a tissue culture model employing monkey kidney epithelial cells (BGM) labeled either with 51 chromium or [3H]arachidonate. The cells could be killed in a synergistic manner following exposure to combinations among H2O2 and the following membrane-damaging agents: streptolysins S (SLS) and O (SLO), poly-D-lysine, arachidonic acid, eicosapentanoic acid, arachidic acid, lysophosphatidylcholine, lysophosphatidylinositol, lysophosphatidylglycerol, ethanol, and sodium taurocholate. Peroxyl radical (ROO) generated by azobisdiamidinopropane dihydrochloride (AAPH) further enhanced cell killing induced by SLS, SLO, and nitroprusside when combined with H2O2 and trypsin. BGM cells labeled either with chromium or with tritiated arachidonate, which had been treated with increasing concentrations of sodium nitroprusside (a donor of NO) and with subtoxic amounts of SLS and H2O2, were also killed in a synergistic manner and also lost a substantial amounts of their arachidonate label. Both cell killing and the release of membrane lipids were totally inhibited by hemoglobin (an NO scavenger) but not by methylene blue, an antagonist of NO2-BGM cells that had been treated with increasing concentrations of taurocholic acid were killed in a synergistic manner by a mixture of subtoxic amounts of ethanol, H2O2, and crystalline trypsin (quadruple synergism). Normal human serum possessing IgM complement-dependent cytotoxic antibodies against Ehrlich ascites tumor cells were killed in a dose-dependent fashion. Cell killing was doubled by the addition of H2O2. Cell killing and the release of membrane lipids by all the mixture of agonists tested were both strongly inhibited by the antioxidants catalase, Mn2+, vitamin A, and by fresh carrot juice. It appears that in order to overcome the antioxidant capacities of the epithelial cells, a variety of membrane-damaging agents had to be present in the reaction mixtures. Taken together, it might be speculated that the killing of mammalian cells in infectious and in inflammatory sites is a synergistic phenomenon that might be inhibited by antagonizing the cross-talk among the various proinflammatory agonists generated by microorganisms by activated phagocytes or by combinations among these agents. Our studies might also open up new approaches to the assessment of the toxicity of xenobiotics and of safe drugs to mammalian cells by employing tissue culture techniques. VL - 19 IS - 1 ER - TY - ABST T1 -

Inflammation: more than one explanation

Y1 - 1995 A1 - Isaac Ginsburg AB - I read with interest the EHP supplement on oxygen radicals and lung injury (vol. 102, supplement 10). I would like to take this opportunity to comment about this supplement and raise a key issue concerning the major concepts regarding the mechanisms of cellular injury in inflammatory diseases. As an active investigator in this field of research, I cannot fully understand why there was no mention in the supplement about the basic understanding that cellular damage in inflammation is multifactorial. The nonexpert reader of this supplement might receive an erroneous impression that oxygen radicals, per se, are the exclusive toxic agonists that induce cellular injury. Many in this field share the view that cellular damage in inflammatory diseases might be caused by a "coordinated cross-talk" among oxidants, membrane-damaging agents, proteinases, arachidonic acid metabolites, phospholipases, cationic proteins, and cytokines. All these agents are likely to be present in sites of infection and inflammation. But sadly, none of the publications elaborating on this multifactorial view are quoted in modern textbooks or in symposia on inflammation and inflammatory diseases. Instead, the literature is filled with publications that insist on a single agonist, be it an oxidant, a protease, a cytokine, etc., in experimental models. No attempt to integrate the various agonists into the full picture is made. Several of our publications (1-7) deal with synergistic interactions among multiple proinflammatory agonists in cellular injury during inflammation. I believe that this issue is important, timely, and might contribute to an understanding of how drugs, chemicals, and xenobiotics function in vivo. Isaac Ginsburg Hadassah School of Dental Medicine Hebrew University Jerusalem JF - Environmental Health Perspectives VL - 103 IS - 11 ER - TY - JOUR T1 -

Invited Review: Cell Damage in Inflammatory and Infectious Sites Might Involve A Coordinated “Cross-Talk” Among Oxidants, Microbial Haemolysins and Ampiphiles, Cationic Proteins, Phospholipases, Fatty Acids, Proteinases and Cytokines (An Overview)

JF - Free Radical Research Y1 - 1995 A1 - Isaac Ginsburg A1 - Ron Kohen VL - 22 IS - 6 ER - TY - JOUR T1 -

 

Effect of lysophosphatidic acid on motility, polarisation and metabolic burst of human neutrophils

JF - FEMS Immunology and Medical Microbiology Y1 - 1994 A1 - Isaac Ginsburg AB - Comment on Effect of lysophosphatidic acid on motility, polarisation and metabolic burst of human neutrophils. [FEMS Immunol Med Microbiol. 1994] VL - 9 IS - 3 ER - TY - JOUR T1 -

Ethanol synergizes with hydrogen peroxide, peroxyl radical, and trypsin to kill epithelial cells in culture

JF - Free Radical Biology and Medicine Y1 - 1994 A1 - Isaac Ginsburg A1 - Ron Kohen A1 - M. Ligumsky AB - Monkey kidney epithelial cells, labeled with chromium and grown in culture, were killed in a synergistic manner when subtoxic amounts of ethanol were combined either with subtoxic amounts of glucose oxidase-generated hydrogen peroxide, or with mixtures of peroxide and with 2,2'-Azo-bis (2-amidinopropane)HCl (AAPH)-generated peroxyl radical. A further enhancement of cytotoxicity occurred when subtoxic amounts of trypsin were added to mixtures of all three agents. While ethanol alone caused shrinkage of the monolayers and cell rounding, no visible cytotoxic changes were observed. Hydrogen peroxide at the concentrations used (about 1 mM), caused only some cell rounding. On the other hand, cells exposed simultaneously to ethanol and to H2O2 developed extensive membrane damage characterized by the formation of large polar blebs, which is compatible with altered membrane permeability. The presence of trypsin markedly enhanced cellular cytotoxicity induced by mixtures of peroxide, peroxyl radical, and ethanol. This could markedly be depressed by catalase and by dimethylthiourea. The tissue culture model described might serve to further investigate the role played by synergy among oxidants and a variety of membrane-damaging agents, and by xenobiotics in tissue damage induced by inflammatory processes. VL - 16 IS - 2 ER - TY - JOUR T1 -

Can hemolytic streptococci be considered "forefathers" of modern phagocytes? Both cell types freely migrate in tissues and destroy host cells by a "synergistic cross-talk" among their secreted agonists.

JF - Comparative Biochemistry and Physiology Y1 - 1994 A1 - Isaac Ginsburg AB - The biochemical and biological properties of many of the pro-inflammatory agonists generated by catalase-negative hemolytic streptococci and by activated human phagocytes, and the mechanisms by which both cell types destroy tissues in infections and in inflammatory sites, are astonishingly similar. In the pre-antibiotic era, group A hemolytic streptococci, also known by the name Streptococcus pyogenes, were responsible for causing serious and life-threatening diseases, mainly in young individuals. These highly virulent agents cause suppurative lesions in virtually any part of the body, due perhaps to their ability to disseminate freely in tissues. They do this by virtue of their ability to elaborate numerous “spreading factors” and tissuedamaging agents. However, the hallmark of the streptococcus injuries is their ability to initiate non-suppurative sequelae (rheumatic fever, arthritis, chorea and glomerulonephritis). Activated phagocytes (neutrophils, eosinophils, macrophages) might also be involved in the pathogenesis of many inflammatory diseases because of their ability to generate and secrete numerous tissue-damaging agonists. It is perhaps paradoxical that both phagocytes and hemolytic streptococci possess adhesion molecules (Patarroyo, 199 1; Ofek et al., 1975; Hasty et al., 1992; Sela et al., 1993; Albelda et al., 1994), receptors for IgG and for IgA (Christensen et al., 1976; Ginsburg et al., 1982; Burova and Schalen, 1993), receptors for complement (Petty and Todd, 1993), receptors for a variety of serum proteins, and for fibronectin (Littenberg et al., 1987; Simpson et al., 1987; Sela et al., 1993). Both phagocytes (Greenwald and Jamison, 1977; Wright, 1982; Gallin et al., 1992) and streptococci (reviewed by Ginsburg, 1972, 1985, 1986), generate numerous spreading factors (hyaluronidase, DNAse, RNAse, proteinases, acid and neutral hydrolases and complement-destroying enzymes (Wexler et al.. 1985). All these agents might facilitate the movement of the cells through the endothelial and epithelial barriers and into the intercellular spaces, and to depolymerize extracellular matrix proteins and inflammatory exudates which, otherwise, might limit cell movement and their spread in the tissues of the host. The non-immunogenic hyaluronic acid capsule, present on the surface of virulent streptococci, mimics similar components also present on mammalian cells. This mimicry allows the streptococci to survive, unrecognized, by the phagocytic cells. Both streptococci (Ginsburg, 1972; Ginsburg, 1979b; Alouf, 1990; Bernheimer and Rudy, 1986) and phagocytes (Victor et al., 198 1; Kennedy and Becker, 1987; Gallin et al., 1992) generate potent membraneperforating agents (hemolysins, phospholipases) which are capable of killing host cells by boring “holes” in their plasma membranes. Both streptococci (Suzuki and Vogt, 1966; Vogt et al., 1983) and phagocytes (Elsbach and Weiss, 1992; Spitznagel, 1990; Lehrer, 1993) also generate a large variety of highly cationic arginine- and cysteine-rich bactericidal and cytocidal proteins. These agents are also capable of activating the respiratory burst in neutrophils (Ginsburg, 1987, 1989) and also of functioning as opsonins (Ginsburg, 1987, 1989). Polycations might also enhance the adherence of neutrophils to targets (Oseas et al., 1981) and thus facilitate delivery of the toxic agonist directly upon the targets. This property is also shared by streptococci possessing cell-bound streptolysin S (Ginsburg and Harris, 1965; Ginsburg and Varani, 1993). Phagocytes and hemolytic streptococci produce either cytokines (West, 1990; Badwey et al., 1991) or a pyrogenic super-antigen (erythrogenic toxin; see Hensler et al., 1993), respectively, which prime phagocytes to generate excessive amounts of reactive oxygen species (ROS) and of lipid mediators of inflammation. Streptococci also generate a surface amphiphile (lipoteichoic acid-LTA) (Ginsburg et al., 1988) which, like lipopolysaccharides (LPS) of Gramnegative rods (Forehand et al., 1989, 1991) also primes neutrophils to generate excessive amounts of ROS. A possible “genetical” linkage between the highly anti-phagocytic surface component, the M-protein of streptococci and human proteins, has been found (Fischetti et al., 1988). Seventy percent of the Mprotein molecule has a tertiary structure of coiled-coil, which is also a characteristic either of tropomyosin, myosin or fibrinogen. Group A hemolytic streptococci also possess two sets of antigens which crossreact with human heart, kidney, brain, skin, myosin and perhaps also with leukocytes (Ayoub and Kaplan, 1991: Stollerman, 1975, 1991; Trentin, 1967; Kaplan, 1967; Ginsburg, 1972; Krisher and Cunningham, 1985; Swerlick and Cunningham. 1986). This led to the hypothesis that the development of crossreactive immunity, in susceptible hosts (Stollerman, 1975, 1991) might be responsible for the pathogenesis of rheumatic fever. arthritis, chorea and nephritis, that are the hallmarks of the post-streptococcal sequelae. Since the crossreactive antibodies isolated from rheumatic fever patients were not cytotoxic to cardiac tissue, their role, if any, in the pathogenesis of tissue damage remains to be established. Most importantly, however, both activated phagocytes and the catalase-negative hemolytic streptococci generate large amounts of H2 O2 (Avery and Morgan, 1924; Ginsburg, 1972; Halliwell and Gutteridge, 1989; Klebanoff and Clark, 1978; Klebanoff, 1992). It therefore stands to reason that both phagocytes and streptococci might cause cellular damage by a tight and wellorchestrated and synergistic collaboration among their secreted agonists (see below). Furthermore, extracellular products elaborated by both phagocytes and streptococci during their encounter in infectious sites, might also interact to amplify cellular damage. Such interactions might take place when H20Z generated by streptococci might be effectively utilized by neutrophils of patients suffering of chronic granulomatous disease of childhood (CGD), which possess a defective NADPH oxidase (Smith and Curnutte, 1991). Such an interaction might not only restore the ability of the CGD phagocytes to kill bacteria, but might also, paradoxically, lead to enhanced cellular damage provided that additional agonists are also present (see below). It is thus tempting to speculate that, mainly from functional and perhaps also from evolutionary points of view, hemolytic streptococci and other toxigenic bacteria (Clostridiae) might perhaps be considered “forefathers of modern phagocytes”. However, it should also be emphasized that evolution displays many examples where basic and parallel biological phenomena might appear in phyla far removed from each other, with no apparent common genetical basis. This emphasizes the successfulness of the strategy, since two totally separate evolutionary pathways have led to it. VL - 109 IS - 2 ER - TY - JOUR T1 -

MANGANESE AND GLYCINE PROTECT AGAINST ETHANOL INDUCED GASTRIC INJURY IN THE RAT

JF - Gastroenterology Y1 - 1993 A1 - M. Ligumsky A1 - M. Sestieri A1 - E. Okon A1 - Isaac Ginsburg AB - Oxygen-derived species are implicated in the pathogenesis of tissue damage in experimental models such as ethanol-induced gastric injury as well as in certain clinical conditions. The aim of this study was to examine the protective effect of manganese and glycine, previously shown to act as H202 scavengers, on ethanol-induced gastric lesions in the rat: MnCl2 and glycine (12.5-50mg/rat) were injected s.c up to 6 hours prior to oral administration of 96% ethanol and the extent of mucosal damage was evaluated 1 hour later by gross and microscopic score. Mn and glycine pre-treatment induced a dose-dependent inhibition of lesion formation. Maximal protection was observed when agents were applied 4 hours prior to the insult. Gross damage was also markedly prevented by pre-treatment with dimethyl-thiourea (DHTU,75mg/Kg), but not by allopurinol. Mixtures of subtoxic concentrations of ethanol and H202 were highly lethal for monkey kidney epithelial cells in culture. Cell killing in this model was markedly attenuated by catalase and DMTU and to a lesser degree by Mn+2 . These results imply that ethanol-induced gastric damage may in part, involve generation of oxygen derived species, independent of the xanthine oxidase system. Mn+2 and glycine provide marked gastro- protection, acting possibly as oxygen radical scavengers. VL - 104 IS - 4 ER - TY - JOUR T1 -

Cimetidine modulates chemiluminescence and superoxide generation by neutrophils

JF - Inflammopharmacology Y1 - 1993 A1 - Ron Kohen A1 - R. Misgav A1 - Isaac Ginsburg AB - Cimetidine, a known H2 blocker, markedly inhibited the generation of luminol-dependent chemiluminescence (LDCL) and the generation of Superoxide by human neutrophils (PMNs) stimulated by polycation-opsonized streptococci. Cimetidine also inhibited LDCL generation in peritoneal PMNs derived from mice pre-injected with this drug. The elucidation of the mechanisms of LDCL inhibition involved the employment of a variety of cimetidine analogues. The most effective inhibitory activity, besides cimetidine, was displayed by histamine, histidine, imidazole acetate, anserine and ergothionine. Imidazole, carnosine and homocarnosine had no inhibitory effect on oxygen radical generation. The possible mechanisms by which cimetidine and certain of its analogues affect the respiratory burst in leucocytes is discussed. VL - 2 IS - 1 ER - TY - JOUR T1 -

Interaction of viable group A streptococci and hydrogen peroxide in killing of vascular endothelial cells

JF - Free Radical Biology and Medicine Y1 - 1993 A1 - Isaac Ginsburg A1 - James Varani AB - Previous studies have shown that the streptococcal hemolysin, streptolysin S, is capable of interacting with hydrogen peroxide (H2O2) to injure vascular endothelial cells (Free Radic. Biol. Med. 7:369-376; 1989). To extend these observations, intact group A streptococci (strain 203S) were examined for ability to injure endothelial cells alone and for ability to injure the same cells in the presence of sublethal concentrations of H2O2 (generated from glucose/glucose oxidase). While neither control bacteria nor bacteria that had been pretreated with poly-L-histidine to render them cationic were cytotoxic to endothelial cells by themselves under the conditions of the experiment, endothelial cells were injured by combinations of streptococcal cells and sublytic amounts of H2O2. Taken together, these data suggest that the sequelae which often occur following primary infection with group A streptococci may be the result of a combined assault of host inflammatory cells and the invading bacteria on the vascular lining cells of the host. VL - 14 IS - 5 ER - TY - JOUR T1 -

Killing of endothelial cells and release of arachidonic acid. Synergistic effects among hydrogen peroxide, membrane-damaging agents, cationic substances, and proteinases and their modulation by inhibitors.

JF - Inflammation Y1 - 1993 A1 - Isaac Ginsburg A1 - RS Mitra A1 - Douglas F. Gibbs A1 - James Varani A1 - Ron Kohen AB - 51Chromium-labeled rat pulmonary artery endothelial cells (EC) cultivated in MEM medium were killed, in a synergistic manner, by mixtures of subtoxic amounts of glucose oxidase-generated H2O2 and subtoxic amounts of the following agents: the cationic substances, nuclear histone, defensins, lysozyme, poly-L-arginine, spermine, pancreatic ribonuclease, polymyxin B, chlorhexidine, cetyltrimethyl ammonium bromide, as well as by the membrane-damaging agents phospholipases A2 (PLA2) and C (PLC), lysolecithin (LL), and by streptolysin S (SLS) of group A streptococci. Cytotoxicity induced by such mixtures was further enhanced by subtoxic amounts either of trypsin or of elastase. Glucose-oxidase cationized by complexing to poly-L-histidine proved an excellent deliverer of membrane-directed H2O2 capable of enhancing EC killing by other agonists. EC treated with rabbit anti-streptococcal IgG were also killed, in a synergistic manner, by H2O2, suggesting the presence in the IgG preparation of cross-reactive antibodies. Killing of EC by the various mixtures of agonists was strongly inhibited by scavengers of hydrogen peroxide (catalase, dimethylthiourea, MnCl2), by soybean trypsin inhibitor, by polyanions, as well as by putative inhibitors of phospholipases. Strong inhibition of cell killing was also observed with tannic acid and by extracts of tea, but less so by serum. On the other hand, neither deferoxamine, HClO, TNF, nor GTP gamma S had any modulating effects on the synergistic cell killing. EC exposed either to 6-deoxyglucose, puromycin, or triflupromazin became highly susceptible to killing by mixtures of hydrogen peroxide with several of the membrane-damaging agents. While maximal synergistic EC killing was achieved by mixtures of H2O2 with either PLA2, PLC, LL, or with SLS, a very substantial release of [3H]arachidonic acid (AA), PGE2, and 6-keto-PGF occurred only if a proteinase was also added to the mixture of agonists. The release of AA from EC was markedly inhibited either by scavengers of H2O2, by proteinase inhibitors, by cationic agents, by HClO, by tannic acid, and by quinacrin. We suggest that cellular injury induced in inflammatory and infectious sites might be the result of synergistic effects among leukocyte-derived oxidants, lysosomal hydrolases, cytotoxic cationic polypeptides, proteinases, and microbial toxins, which might be present in exudates. These "cocktails" not only kill cells, but also solubilize AA and several of its metabolites. However, AA release by the various agonists can be also achieved following attack by leukocyte-derived agonists on dead cells. It is proposed that treatment by "cocktails" of adequate antagonists might be beneficial to protect against cellular injury in vivo. VL - 17 IS - 3 ER - TY - JOUR T1 -

Chemiluminescence in activated human neutrophils: role of buffers and scavengers

JF - Inflammation Y1 - 1993 A1 - Isaac Ginsburg A1 - R. Misgav A1 - D. F. Gibbs A1 - James Varani A1 - Ron Kohen AB - Human neutrophils (PMNs) suspended in Hanks' balanced salt solution (HBSS), which are stimulated either by polycation-opsonized streptococci or by phorbol myristate acetate (PMA), generate nonamplified (CL), luminol-dependent (LDCL), and lucigenin-dependent chemiluminescence (LUCDCL). Treatment of activated PMNs with azide yielded a very intense CL response, but only a small LDCL or LUCDCL responses, when horse radish peroxidase (HRP) was added. Both CL and LDCL depend on the generation of superoxide and on myeloperoxidase (MPO). Treatment of PMNs with azide followed either by dimethylthiourea (DMTU), deferoxamine, EDTA, or detapac generated very little CL upon addition of HRP, suggesting that CL is the result of the interaction among H2O2, a peroxidase, and trace metals. In a cell-free system practically no CL was generated when H2O2 was mixed with HRP in distilled water (DW). On the other hand significant CL was generated when either HBSS or RPMI media was employed. In both cases CL was markedly depressed either by deferoxamine or by EDTA, suggesting that these media might be contaminated by trace metals, which catalyzed a Fenton-driven reaction. Both HEPES and Tris buffers, when added to DW, failed to support significant HRP-induced CL. Nitrilotriacetate (NTA) chelates of Mn2+, Fe2+, Cu2+, and Co2+ very markedly enhanced CL induced by mixtures of H2O2 and HRP when distilled water was the supporting medium. Both HEPES and Tris buffer when added to DW strongly quenced NTA-metal-catalyzed CL. None of the NTA-metal chelates could boost CL generation by activated PMNs, because the salts in HBSS and RPMI interfered with the activity of the added metals. CL and LDCL of activated PMNs was enhanced by aminotriazole, but strongly inhibited by diphenylene iodonium (an inhibitor of NADPH oxidase) by azide, sodium cyanide (CN), cimetidine, histidine, benzoate, DMTU and moderately by superoxide dismutase (SOD) and by deferoxamine LUCDCL was markedly inhibited only by SOD but was boosted by CN. Taken together, it is suggested that CL generated by stimulated PMNs might be the result of the interactions among, NADPH oxidase, (inhibitable by diphenylene iodonium), MPO (inhibitable by sodium azide), H2O2 probably of intracellular origin (inhibitable by DMTU but not by catalase), and trace metals that contaminate salt solutions. The nature of the salt solutions employed to measure CL in activated PMNs is critical. VL - 17 IS - 3 ER - TY - JOUR T1 -

Synergism among oxidants, proteinases, phospholipases, microbial hemolysins, cationic proteins, and cytokines

JF - Inflammation Y1 - 1992 A1 - Isaac Ginsburg A1 - R. Misgav A1 - A. Pinson A1 - J Varani A1 - P. A. Ward A1 - R. Kohen AB - A striking similarity exists between the pathogenetic properties of group A streptococci and those of activated mammalian professional phagocytes (neutrophils, macrophages). Both types of cells are endowed by the ability to adhere to target cells; to elaborate oxidants, hydrolases, and membrane-active agents (hemolysins, phospholipases); and to freely invade tissues and destroy cells. From the evolutionary point of view, streptococci might justifiably be considered the forefathers of “modern” leukocytes. Our earlier findings that synergy between a streptococcal hemolysin (streptolysin S, SLS) and a streptococcal thiol-dependent proteinase and between cytotoxic antibodies + complement and streptokinase-activated plasmin readily killed tumor cells, led us to hypothesize that by analogy to the pathogenetic mechanisms of streptococci, the mechanisms of tissue destruction initiated by activated leukocytes in inflammatory sites, as well as in tissues undergoing episodes of ischemia and reperfusion, might also be the result of the synergistic effects among leukocyte-derived oxidants, phospholipases, proteinases, cytokines, and cationic proteins. The current report extends our previous synergy studies with endothelial cells to two additional cell types-monkey kidney epithelial cells and rat beating heart cells. Monolayers of51Cr-labeled cells that had been treated by combinations of sublytic amounts of hydrogen peroxide (generated either by glucose oxidase, xanthine-xanthine oxidase, or by paraquat) and with sublytic amounts of a variety of membrane-active agents (streptolysin S, phospholipases A2 and C, lysophosphatides, histone, chlorhexidine) were killed in a synergistic manner (double synergy). Crystalline trypsin markedly enhanced cell killing by combinations of oxidant and the membrane-active agents (triple synergy). Injury to the cells was characterized by the appearance of large membrane blebs that detached from the cells and floated freely in the media, looking like lipid droplets. Cytotoxicity induced by the various combinations of agonists was depressed, to a large extent, by scavengers of hydrogen peroxide (catalase, dimethyl thiourea, and by Mn2+) but not by SOD or by deferoxamine. When cationic agents were employed together with hydrogen peroxide, polyanions (heparin, polyanethole sulfonate) were also found to inhibit cell killing. It is proposed that in order to effectively combat the deleterious toxic effects of leukocyte-derived agonists on cells and tissues, antagonistic “cocktails” comprised of cationized catalase, cationized SOD, dimethylthiourea, Mn2+ + glycine, proteinase inhibitors, putative inhibitors of phospholipases, and polyanions might be concocted. The current literature on synergistic phenomena pertaining to mechanisms of cell and tissue injury in inflammation is selectively reviewed. VL - 16 IS - 5 ER - TY - JOUR T1 -

Human neutrophils stimulated by cetyltrimethyl ammonium bromide generate luminol-amplified and non-amplified chemiluminescence but no superoxide production: A paradox

JF - Inflammopharmacology Y1 - 1992 A1 - Isaac Ginsburg A1 - R. Misgav A1 - A. Samuni A1 - D. F. Gibbs A1 - J Varani A1 - R. Kohen AB - Human neutrophils (PMNs) stimulated by sub-toxic concentrations of cetyltrimethyl ammonium bromide (CETAB) (37 μmol/L) generated intense luminol-dependent chemiluminescence (LDCL) and moderate non-amplified chemiluminescence (CL), but, paradoxically, generation of superoxide (as assayed by cytochrome c reduction, lucigenin-dependent chemiluminescence, nitroblue tetrazolium reduction test (NBT), spin trapping or hydrogen peroxide (Thurman reaction) and also oxygen uptake, were not observed. LDCL generation, however, was dependent on the viability of the PMNs. On the other hand, CETAB failed to induce CL in PMNs obtained from two children with an X-linked chronic granulomatous disease of childhood. CETAB inhibited superoxide generation by PMNs stimulated by phorbol-12-myristate-13-acetate (PMA), histone or polyhistidine-opsonized streptococci. It also inhibited NBT reduction in PMNs stimulated by PMA or by cationized streptococci. Generation of LDCL by CETAB-stimulated PMNs was inhibited by azide, cyanide, thiourea, dimethylthiourea, histidine, cimetidine, chloroquine, nordihydroguaiaretic acid and bromophenacyl bromide and partially so, about 50%, by superoxide dismutase (SOD), by TEMPOL (a SOD mimetic) and H-7, a protein kinase c inhibitor, but not by catalase, desferrioxamine, taurine or methionine. PMNs stimulated by CETAB in the presence of azide generated a large peak of LDCL when treated with horseradish peroxidase (HRP), suggesting that hydrogen peroxide, perhaps of intracellular origin, was involved. Such enhanced HRP-stimulated light emission was inhibited by catalase and by desferrioxamine, suggesting that the HRP-catalysed reaction also depended on some source of trace metals. CETAB also markedly enhanced CL generated by a cell-free mixture of hydrogen peroxide and HRP, which was quenched to a large extent by catalase, dimethylthiourea or desferrioxamine, again suggesting that light emission might be linked with trace metals present in the salt solutions employed. It is postulated that CETAB-induced CL in human PMNs is the result of the interaction of hydrogen peroxide, presumably of intracellular source, a trace metal, and a peroxidase (myeloperoxidase). This phenomenon might be unrelated to the classical respiratory burst, which is always accompanied by oxygen consumption, and to the generation of a variety of oxygen-derived species linked with the activation of the NADPH oxidase present in the cell membrane. VL - 1 IS - 4 ER - TY - JOUR T1 -

The SOD like activity of copper:carnosine, copper:anserine and copper:homocarnosine complexes

JF - Free radical research communications Y1 - 1991 A1 - Ron Kohen A1 - R. Misgav A1 - Isaac Ginsburg AB - Carnosine, anserine and homocarnosine are natural compounds which are present in high concentrations (2-20 mM) in skeletal muscles and brain of many vertebrates. We have demonstrated in a previous work that these compounds can act as antioxidants, a result of their ability to scavenge peroxyl radicals, singlet oxygen and hydroxyl radicals. Carnosine and its analogues have been shown to be efficient chelating agents for copper and other transition metals. Since human skeletal muscle contains one-third of the total copper in the body (20-47 mmol/kg) and the concentration of carnosine in this tissue is relatively high, the complex of carnosine:copper may be of biological importance. We have studied the ability of the copper:carnosine (and other carnosine derivatives) complexes to act as superoxide dismutase. The results indicate that the complex of copper:carnosine can dismute superoxide radicals released by neutrophils treated with PMA in an analogous mechanism to other amino acids and copper complexes. Copper:anserine failed to dismute superoxide radicals and copper:homocarnosine complex was efficient when the cells were treated with PMA or with histone-opsonized streptococci and cytochalasine B. The possible role of these compounds to act as physiological antioxidants that possess superoxide dismutase activity is discussed. VL - 12-13 IS - 1 ER - TY - JOUR T1 -

Hydrogen peroxide-induced cell and tissue injury: protective effects of Mn2+

JF - Inflammation Y1 - 1991 A1 - J Varani A1 - Isaac Ginsburg A1 - D. F. Gibbs A1 - P.S Mukhopadhyay A1 - C Sulavik A1 - K. J. Johnson A1 - J.M. Weinberg A1 - U. S. Ryan A1 - P. A. Ward AB - Recent evidence indicates that under in vitro conditions, superoxide anion and hydrogen peroxide (H2O2) are unstable in the presence of manganese ion (Mn2+). The current studies show that in the presence of Mn2+, H2O2-mediated injury of endothelial cells is greatly attenuated. A source of bicarbonate ion and amino acid is required for Mn2+ to exert its protective effects. Injury by phorbol ester-activated neutrophils is also attenuated under the same conditions. EDTA reverses the protective effects. Acute lung injury produced in vivo in rats by intratracheal instillation of glucose-glucose oxidase is almost completely blocked in rats treated with Mn2+ and glycine. Conversely, treatment of rats with EDTA, a chelator of Mn2+, markedly accentuates lung injury caused by glucose-glucose oxidase. These data are consistent with the findings of others that Mn2+ can facilitate direct oxidation of amino acids with concomitant H2O2 disproportionation. This could form the basis of a new therapeutic approach against oxygen radical-mediated tissue injury. VL - 15 IS - 4 ER - TY - JOUR T1 -

Comparative effects of azapropazone on cellular events at inflamed sites.

JF - Journal of Pharmacy and Pharmacology Y1 - 1989 A1 - K. D. Rainsford A1 - A. Davies A1 - L. Mundy A1 - Isaac Ginsburg AB - Comparative effects of azapropazone on cellular events at inflamed sites. Influence on joint pathology in arthritic rats, leucocyte superoxide and eicosanoid production, platelet aggregation, synthesis of cartilage proteoglycans, synovial production and actions of interleukin-1 in cartilage resorption correlated with drug uptake into cartilage in-vitro. Azapropazone (APZ) has been compared with standard NSAIDs in title systems to establish aspects of its mode of action on cellular events at inflamed sites. APZ (150 mg kg-1 day-1) given for 10-13 days exhibited a reduction in joint pathology in established adjuvant arthritis in rats comparable with that of indomethacin (2 mg kg-1 day-1) and clobuzarit (20 mg kg-1 day-1). APZ was shown to be a potent inhibitor of the production of leucocyte superoxide and synovial interleukin-1 (IL-1)-like activity and stimulated articular cartilage proteoglycan synthesis, but was ineffective as an inhibitor of platelet aggregation or IL-1 induced cartilage degradation in-vitro. These in-vitro effects may have relevance to the mode of action of this weak inhibitor of prostaglandin synthesis. VL - 41 IS - 5 ER - TY - JOUR T1 -

Vascular endothelial cell killing by combinations of membrane-active agents and hydrogen peroxide

JF - Free Radical Biology and Medicine Y1 - 1989 A1 - Isaac Ginsburg A1 - Douglas F. Gibbs A1 - Lucia Schuger A1 - Kent J Johnson A1 - Una S Ryan A1 - Peter A Ward A1 - James Varani AB - Previous studies have demonstrated that a number of membrane-active agents are capable of binding to the surface of polymorphonuclear leukocytes (PMN) resulting in an augmentation of superoxide anion and hydrogen peroxide (H2O2) production in response to soluble stimuli. It is now demonstrated that these same membrane-active agents can bind to the surface of endothelial cells and enhance their susceptibility to killing by H2O2. Membrane-active agents which are capable of synergizing with H2O2 include cationic proteins, cationic poly-amino acids, lysophosphatides and enzymes which are capable of degrading membrane phospholipids (e.g., phospholipase C, phospholipase A2 and streptolysin S). In each case, treatment of the target cells with the membrane-active agent and H2O2 produces greater damage than the sum of the damage produced by either agent separately. Since inflammatory lesions, particularly sites of bacterial infection, may contain a rich mixture of cationic substances, phospholipases and phospholipid breakdown products, these substances may contribute to the tissue damage observed at sites of inflammation by enhancing endothelial cell sensitivity to PMN-generated H2O2 as well as by augmenting the generation of H2O2 by PMNs. VL - 7 IS - 4 ER - TY - JOUR T1 -

Formation and use of poly-L-histidine-catalase complexes: protection of cells from hydrogen peroxide-mediated injury

JF - Inflammation Y1 - 1989 A1 - Douglas F. Gibbs A1 - James Varani A1 - Isaac Ginsburg AB - Insoluble complexes of poly-L-histidine (polyhistidine) and catalase were prepared by mixing the two reactants together in solution at pH 5.5 and subsequently elevating the pH to approximately 7.0, at which point they precipitated. Complexes formed at optimal ratios of polyhistidine to catalase contained essentially all of the catalase present in the original solution. The catalase present in such complexes contained greater than 50% of the H2O2-inhibiting activity of the native catalase used to prepare the complexes. The insoluble complexes rapidly bound to viable endothelial cells and were resistant to removal by extensive washing. The presence of polyhistidine-catalase complexes on the cell surface protected the cells against injury mediated by H2O2 or activated polymorphonuclear leukocytes. These data show that polyhistidine-catalase complexes can be prepared that have a high affinity for cells and that retain catalase activity. These complexes may be useful in treating inflammatory conditions in which it is necessary to maintain a high local concentration of inhibitor. VL - 13 IS - 4 ER - TY - JOUR T1 -

Lysophosphatides enhance superoxide responses of stimulated human neutrophils

JF - Inflammation Y1 - 1989 A1 - Isaac Ginsburg A1 - Peter A Ward A1 - James Varani AB - Human neutrophils which are pretreated with subtoxic concentrations of a variety of lysophosphatides (lysophosphatidylcholine, lysophosphatidylcholine oleoyl, lysophosphatidylcholine myrioyl, lysophosphatidylcholine stearoyl, lysophosphatidylcholine gamma-O-hexadecyl, lysophosphatidylinositol, and lysophosphatidylglycerol) act synergistically with neutrophil agonists phorbol myristate acetate, immune complexes, poly-L-histidine, phytohemagglutinin, and N-formyl-methionyl-leucyl-phenyalanine to cause enhanced generation of superoxide (O2-). None of the lyso compounds by themselves caused generation of O2-. The lyso compounds strongly bound to the neutrophils and could not be washed away. All of the lyso compounds that collaborated with agonists to stimulate O2- generation were hemolytic for human red blood cells. On the other hand, lyso compounds that were nonhemolytic for red blood cells (lysophosphatidylcholine caproate, lysophosphatidylcholine decanoyl, lysophosphatidylethanolamine, lysophosphatidylserine) failed to collaborate with agonists to generate synergistic amounts of O2-. However, in the presence of cytochalasin B, both lysophosphatidylethanolamine and lysophosphatidylserine also markedly enhanced O2- generation induced by immune complexes. O2- generation was also very markedly enhanced when substimulatory amounts of arachidonic acid or eicosapentanoic acid were added to PMNs in the presence of a variety of agonists. On the other hand, neither phospholipase C, streptolysin S (highly hemolytic), phospholipase A2, phosphatidylcholine, nor phosphatidylcholine dipalmitoyl (all nonhemolytic) had the capacity to synergize with any of the agonists tested to generate enhanced amounts of O2-. The data suggest that in addition to long-chain fatty acids, only those lyso compounds that possess fatty acids with more than 10 carbons and that are also highly hemolytic can cause enhanced generation of O2- in stimulated PMNs. VL - 13 IS - 2 ER - TY - JOUR T1 -

Interaction of mammalian cells with polymorphonuclear leukocytes: relative sensitivity to monolayer disruption and killing

JF - Inflammation Y1 - 1989 A1 - Isaac Ginsburg A1 - Douglas F. Gibbs A1 - James Varani AB - Monolayers of murine fibrosarcoma cells that had been treated either with histone-opsonized streptococci, histone-opsonized Candida globerata, or lipoteichoic acid-anti-lipoteichoic acid complexes underwent disruption when incubated with human polymorphonuclear leukocytes (PMNs). Although the architecture of the monolayers was destroyed, the target cells were not killed. The destruction of the monolayers was totally inhibited by proteinase inhibitors, suggesting that the detachment of the cells from the monolayers and aggregation in suspension were induced by proteinases releases from the activated PMNs. Monolayers of normal endothelial cells and fibroblasts were much resistant to the monolayer-disrupting effects of the PMNs than were the fibrosarcoma cells. Although the fibrosarcoma cells were resistant to killing by PMNs, killing was promoted by the addition of sodium azide (a catalase inhibitor). This suggests that the failure of the PMNs to kill the target cells was due to catalase inhibition of the hydrogen peroxide produced by the activated PMNs. Target cell killing that occurred in the presence of sodium azide was reduced by the addition of a "cocktail" containing methionine, histidine, and deferoxamine mesylate, suggesting that hydroxyl radicals but not myeloperoxidase-catalyzed products were responsible for cell killing. The relative ease with which the murine fibrosarcoma cells can be released from their substratum by the action of PMNs, coupled with their insensitivity to PMN-mediated killing, may explain why the presence of large numbers of PMNs at the site of tumors produced in experimental animals by the fibrosarcoma cells is associated with an unfavorable outcome. VL - 13 IS - 5 ER - TY - JOUR T1 -

Endothelial cell killing by neutrophils. Synergistic interaction of oxygen products and proteases.

JF - The American Journal of Pathology Y1 - 1989 A1 - James Varani A1 - Isaac Ginsburg A1 - L. Schuger A1 - D. F. Gibbs A1 - J. Bromberg A1 - K. J. Johnson A1 - U. S. Ryan A1 - P. A. Ward AB - Killing of rat pulmonary artery endothelial cells by activated polymorphonuclear leukocytes (PMNs), as measured at 4 hours, is catalase sensitive, iron dependent, and unaffected by addition of protease inhibitors. If the time course for exposure of endothelial cells to activated PMNs is extended to 18 hours, progressive injury occurs. Endothelial cell injury resulting at 18 hours is partially inhibited by catalase and partially inhibited by soybean trypsin inhibitor. Together, these two inhibitors function synergistically to protect the cells from injury. Exposure of endothelial cells to reagent H2O2 and purified proteolytic enzymes (trypsin, chymotrypsin, elastase, and cathepsin G) mimics the effects of activated PMNs: H2O2 alone is cytotoxic with maximal killing achieved by 4 hours; proteolytic enzymes produce cytotoxicity only at high concentrations and only after prolonged incubation (longer than 8 hours); and, in combination, H2O2 and proteolytic enzymes act synergistically. These data provide compelling evidence that PMN-mediated injury of endothelial cells involves interaction between oxygen products and proteases. VL - 135 IS - 3 ER - TY - JOUR T1 -

Cationic polyelectrolytes: potent opsonic agents which activate the respiratory burst in leukocytes

JF - Free radical research communications Y1 - 1989 A1 - Isaac Ginsburg AB - Bacteria and yeasts which are "opsonized" with cationic polyelectrolytes (poly-L-arginine, poly-L-histidine and arginine-rich histone) are avidly endocytosed by both "professional" and "non-professional" phagocytes. The cationized particles also strongly activate the respiratory burst in neutrophils and in macrophages leading to the generation of chemiluminescence, superoxide and hydrogen peroxide. On the other hand, lysine and ornithine-rich polymers are poor opsonic agents. Poly L-arginine is unique in its capacity to act synergistically with lectins, with chemotactic peptides and with cytochalasin B to generate large amounts of chemiluminescence and superoxide in human neutrophils. Unlike polyarginine, polyhistidine, in the absence of carrier particles, is one of the most potent stimulators of superoxide generations, known. Neutrophils treated with cetyltrimethylammonium bromide fail to generate superoxide, but generate strong luminol-dependent chemiluminescence which is totally inhibited by sodium azide and by thiourea. Neutrophils injured by cytolytic agents (saponin, digitonin, lysolecithin) lose their chemiluminescence and superoxide-generating capacities upon stimulation by a variety of ligands. These activities are however regained by the addition of NADPH. Lysolecithin can replace polyarginine in a "cocktail" also containing lectins and cytochalasin B, which strongly activate the respiratory burst. This suggests that polyarginine acts both as a cytolytic agent and as a ligand. Arginine and histidine-rich polyelectrolytes enhance the pathogenic effects of immune complexes in vivo (reversed Arthus phenomenon) presumably by "glueing" them to tissues. Polyhistidine complexed to catalase or to superoxide dismutase, markedly enhances their efficiency as antioxidants. On the other hand polyhistidine complexed to glucose oxidase markedly enhances injury to endothelial cells suggesting that the close association of the cationized enzyme with the plasma membrane facilitates the interaction of hydrogen peroxide with the targets. A variety of cationic agents (histone, polyarginine, polyhistidine, polymyxin B) and membrane-active agents (lysophosphatides, microbial hemolysins) act synergistically with glucose oxidase or with reagent hydrogen peroxide to kill target cells. The mechanisms by which arginine- and histidine-rich polyelectrolytes activate the respiratory burst in neutrophils might involve interaction with G-proteins, the activation of arachidonic acid metabolism and phospholipase A2, or the interaction with myeloperoxidase. Naturally-occurring cationic proteins might modulate several important functions of leukocytes and the course and outcome of the inflammatory process. VL - 8 IS - 1 ER - TY - JOUR T1 -

Bacteriolysis is inhibited by hydrogen peroxide and by proteases.

JF - Agents Actions (Inflammation Research Y1 - 1989 A1 - Isaac Ginsburg AB - Treatment of Staphylococcus aureus in vitro with cationic agents results in the activation of their autolytic wall enzymes and in the degradation of their cell walls. Exposure of staphylococci either to hydrogen peroxide or the proteinases abolished the autolytic process. This effect was totally reversed by catalase and by proteinase inhibitors, respectively. It is suggested that the failure of neutrophils and macrophages to effectively degrade microbial cell wall components in inflammatory sites might be due to the inactivation of the autolytic wall enzymes of bacteria by hydrogen peroxide and by proteinases generated by the activated leukocytes. This might explain the prolonged chronic inflammatory sequelae seen following infections. VL - 28 IS - 3-4 ER - TY - JOUR T1 -

Activation of a murine T-cell hybridoma by cationized bacteria.

JF - Immunology Y1 - 1989 A1 - D N Shapiro, A1 - J Varani A1 - Isaac Ginsburg AB - Cationic particles interact by electrostatic forces with membrane components of diverse cell types, including lymphocytes. Contact with cationized streptococci was shown to induce a murine T-cell hybridoma to transcribe lymphokine mRNA as well as secrete interleukin-2. This activation was accompanied by a rise in intracellular calcium. Cationized streptococci-induced activation of this T-cell hybridoma could be specifically inhibited by either chelating extracellular calcium or by treating with CD4 monoclonal antibody. These data indicate that the in vitro behaviour of T cells can be modulated by charged microbial particles; such interactions may have relevance for chronic inflammation associated with some bacterial infections. VL - 67 IS - 4 ER - TY - JOUR T1 -

Antiarthritic synergism of combined oral and parenteral chrysotherapy. II. Increased inhibition of activated leukocyte oxygen burst by combined gold action

JF - Inflammation Y1 - 1988 A1 - AE. Finkelstein A1 - M. Ladizesky A1 - R. Borinsky A1 - E Kohn A1 - Isaac Ginsburg AB - We have observed an antiarthritic effect of combined chrysotherapy in adjuvant arthritis. Since superoxide radicals (O2-) are potent mediators of rheumatoid inflammation, we studied the combined effect of auranofin (AF) and injectable golds on luminol-dependent chemiluminescence (LDCL) and O2- generation by cytochrome-c reduction of activated leukocytes by different receptor-mediated stimuli: phorbol myristic acetate, 10(-6) M; f-Met-Leu-Phe, 10(-6) M; and poly-L-histidine, 10(-5) M. AF, 0.6 and 0.9 micrograms Au/ml, inhibited 34 and 58% of O2- generation, respectively; the addition to AF of 0.3 micrograms Au/ml of gold thiosulfate (GTS) increased this inhibition to 84 and 97% of the oxygen burst. Similar synergistic potentiation inhibition was obtained by LDCL. When the inhibition of O2- generation by the combined action of AF and GTS was compared with AF + gold sodium thiomalate (GTM), only GTS showed an activation on AF's inhibition of the oxygen burst of human leukocytes. The ligand thiosulfate in equimolar concentrations to GTS had a statistically significant (P less than 0.01) inhibitory effect on AF's blockade of O2- generation during the first 5 min of the interaction with the PMNs; thiomalate had no effect. Sequential pretreatment of PMNs with AF and GTS on O2- generation revealed that for synergism of combined gold action to take place, the cell membrane had to be subjected first to the action of oral gold or to the simultaneous combined action of oral and parenteral gold.(ABSTRACT TRUNCATED AT 250 WORDS) VL - 12 IS - 4 ER - TY - JOUR T1 -

Antiarthritic synergism of combined oral and parenteral chrysotherapy. I. Studies in adjuvant-induced arthritis in rats

JF - Inflammation Y1 - 1988 A1 - AE Finkelstein A1 - M. Ladizesky A1 - R. Borinsky A1 - E Kohn A1 - Isaac Ginsburg AB - In comparative clinical studies of auranofin (AF, oral gold) and parenteral gold in the treatment of rheumatoid arthritis, no difference in efficacy was detected. Since the pharmacologic profiles of these compounds are different, we studied their combined effect on adjuvant arthritis (AA). The effect of AF alone and combined with gold sodium thiomalate (GTM) or gold sodium thiosulfate (GTS) on the excretion of urinary hydroxyproline (UHP) and urinary calcium (UCa), and the articular index of arthritic rats was followed during five weeks of treatment. The excretion of UHP and UCa was significantly inhibited (P less than 0.005) in rats treated with AF combined with GTM or GTS as compared with animals treated with the individual gold compounds. However, the articular index only decreased significantly (P less than 0.02) in the group of rats treated with AF + GTS. The present studies open the possibility that combined treatment with oral and injectable gold provide a new approach for chrysotherapy with an increased antiarthritic potency. VL - 12 IS - 4 ER - TY - JOUR T1 -

The biochemistry of bacteriolysis: paradoxes, facts and myths

JF - Microbiological Sciences Y1 - 1988 A1 - Isaac Ginsburg AB - Degradation of cell wall components of certain microbial species following phagocytosis by neutrophils and macrophages might involve the activation, by leucocyte cationic proteins, of the bacterial autolytic wall enzymes, leading to bacteriolysis. Lysozyme (a distinct cationic agent), which is the main muramidase present in leucocytes and in body fluids, might function not only as an enzyme but also as a potent activator of autolysis. Sulphated polyelectrolytes, proteolytic enzymes and oxygen radicals, which are released in inflammatory sites, might inactivate the autolytic wall enzymes, leading to the accumulation of peptidoglycan-polysaccharide complexes within macrophages. Activated macrophages are instrumental in initiating chronic inflammatory reactions. Undegraded microbial cell wall components also function as immunomodulators and as enhancers of non-specific resistance to infections and to malignancy. VL - 5 IS - 5 ER - TY - JOUR T1 -

Lipoteichoic acid-antilipoteichoic acid complexes induce superoxide generation by human neutrophils

JF - Inflammation Y1 - 1988 A1 - Isaac Ginsburg A1 - SE Fligiel A1 - Peter A Ward A1 - James Varani AB - Human neutrophils (PMNs) which have been incubated with lipoteichoic acid (LTA) from group A streptococci generated large amounts of superoxide (O2- chemiluminescence and hydrogen peroxide when challenged with anti-LTA antibodies. Cytochalasin B further enhanced O2- generation. The onset of O2- generation by the LTA-anti-LTA complexes was much faster than that induced by BSA-anti-BSA complexes. LTA-treated PMNs generated much less O2- when challenged with BSA complexes, suggesting that LTA might have blocked, nonspecifically, some of the Fc receptors on PMNs. PMNs treated with LTA-anti-LTA complexes further interacted with bystander nonsensitized PMNs resulting in enhanced O2- generation, suggesting that small numbers of LTA-sensitized PMNs might recruit additional PMNs to participate in the generation of toxic oxygen species. Protelolytic enzyme treatment of PMNs further enhanced the generation of O2- by PMNs treated with LTA-anti-LTA. Superoxide generation could also be induced when PMNs and anti-LTA antibodies interacted with target cells (fibroblasts, epithelial cells) pretreated with LTA. This effect was also further enhanced by pretreatment of the target cells with proteases. PMNs incubated with LTA released lysosomal enzymes following treatment with anti-LTA antibodies. The amounts of phosphatase, beta-glucoronidase, N-acetylglucosaminidase, mannosidase, and lysozyme release by LTA-anti-LTA complexes were much smaller than those released by antibody or histone-opsonized streptococci, suggesting that opsonized particles are more efficient lysosomal enzyme releasers. However, since the amounts of O2- generated by the LTA complexes equaled those generated by the opsonized particles, it is assumed that the signals for triggering a respiratory burst and lysosomal enzyme secretion might be different. Generation of O2- by LTA complexes was strongly inhibited by lipoxygenase inhibitors but not by cyclooxigenase inhibitors. Also phenylbutazone, trifluorperazine, and DASA markedly inhibited O2- generation induced by LTA complexes. These data suggest that bacterial products in the presence of antibody might have important biological effects on phagocytic cells and that these effects may be inimical to the host. VL - 12 IS - 6 ER - TY - CHAP T1 -

Cocktails of soluble ligands and bacteria opsonized with cationic or anionic polyelectrolytes trigger intense chemiluminescence and superoxide production by leukocytes

T2 - Cellular Chemiluminescence Y1 - 1987 A1 - Isaac Ginsburg A1 - Ruth Borinski ED - Knox Van Dyke ED - Vincent Castranova AB - GENERAL INTRODUCTION. The invasion of the tissues of a host by pathogenic microorganisms is usually followed by a series of sequential humoral and cellular events which include: the generation of chemotactic agents, the directional migration of leukocytes toward the invader, the opsonization of the agents by immunoglobulins and complement components, the intemalization of the agents within phagolysosomes. and eventually by the killing and biodegradation of the ingested agents. The perturbation of the leukocytes membranes by opsonized micro- organisms as well as by a variety of cytolytic agents generated by bacteria is also accompanied by a series of biochemical events which include an “oxygen burst" which culminates in the generation of oxygen radicals, some of which are directly involved in the killing of the ingested agents. Concomitantly with the activation of the oxygen metabolism, granulocytes (PMN)f and macrophages (MQ)f also generate chemiluminescence (CL) which is believed to be a natural consequence of the redox met mbrane perturbation due to phagocytosis. lt may involve the generation of a species of singlet oxygen and hydroxyl radicals or electronically excited carbonyl groups which relax with light emission. A relationship between CL and superoxide production has also been demonstrated by the reduction of CL which occurs following the addition of superoxide dismutase (SOD) to phagocytizing leukocytes. The CL signals which can be further amplified by luminol are also believed to be dependent upon myeloperoxidase (MPO)-catalyzed reactions and/or upon metabolism of arachidonic acid pathway(s). The luminol-de-pendent CL ( LDCL) reaction is currently employed to assess the opsonophagocytic properties of sera as we as for the evaluation of the membrane perturbation which is initiated, in leukocytes, by cytotoxic drugs, and by microbial toxins. ln addition to opsonized particles, a series of soluble ligands, i.e., chemotactic peptides, lectins, phorbol esters, calcium ionopohres, polyanethole sulfonate, and cationic polypeptides have all been shown to stimulate the oxygen burst and to generate CL in neutrophils, monocytes, and macrophages. Because of the relative ease and rapidity with which CL is measured in leukocytes, this method has also become a powerful tool to investigate host-and-parasite interrelationships and to assess defects in leukocyte functions (e.g. , chronic granulomatous disease of childhood (CGD) MPO deficiency, defects in complement components and in immunoglobulins, etc.). Recent studies from our laboratory have described a unique phenomenon which showed that a variety of microbial species can be very effectively “opsonized” by cationic proteins rich in arginine (e.g., histones. poly-L-arginine - PARG). Such opsonized microorganisms are readily internalized not only by "professional" phagocytes (PMNs and macrophages) but also by epithelial cells and by fibroblasts. We have postulated that perturbation of the mammalian cells by the highly-charged polyelectrolytes, coated upon particles, delivers a signal (through electrostatic interactions) to the cytoskeleton resulting in the invagination of the membrane and the formation of a phagocytic vacuole. This phenomenon mimics the cellular events that take place following the stimulation of the leukocyte membrane by antibody and complement-coated particles which function through the F and Cb receptors. Thus, the polycationic ligands may represent "archaic" antibodies capable of stimulating certain membrane sites probably nonspecifically (see Section A.l). Our studies further postulated that if leukocytes “recognize" cationic charges upon particles and respond to them by phagocytosis, such coated particles should also be able to trigger an “oxygen burst" in a fashion similar to that induced either by antibody-coated particles or by other membrane- active agents. Indeed, we have demonstrated tnat very intense LDCL and superoxide production ls triggered in blood leukocytes following stimulation with bacteria and zymosan particles which had been precoated with arginine rich histon PARG and paradoxically also by the anionic polyelectrolytes,.|iquoid. anddextransulfatc. The intensity of the CL signals obtained exceeded by many magnitudes those induced by antibody-coated particles. These findings further suggested that the stimulation of the leukocyte membrane, either simultaneously or sequentially by mixtures of different ligands, each recognizing a different membrane site, may perhaps culminate in a synergistic metabolic response. Such "multiple hits" may therefore generate large quantities of oxygen radicals and CL, presumably due to a more efficient activation of the membrane oxidase and a better assembly of the electron transport system leading to the generation of superoxide. We have chosen to examine agents like the chemotactic peptide F-Met-Leu-Phe (FMLP), a variety of lectins, calcium ionophore, PMA, liquoid, and poly ot-cationic peptides as probes for the stimulation of LDCL and superoxide production by human PMN. We have shown that whereas each ligand alone induced only a very moderate LDCL response in leukocytes, very intense CL signals were generated if the various ligands were employed as “cocktails, suggesting multiple mechanisms of activation of the oxygen metabolism in leukocytes (see also Reference 27). Since inflammatory exudates which accumulate following microbial proliferation in tissues are known to be rich in both cationic and anionic polyelectrolytes, we also postulated that some of these agents may coat either the surface of the leukocytes or the surface of the microorganisms, or both. and thus modulate mutual recognitions leading either to enhanced or depressed membrane perturbation. These changes may be monitored by CL and by the production of superoxide. The present report further expands our observations on the multiple roles played by polycationic and polyanionic agents and of "cocktails" of soluble ligands in the stimulation of the generation of LDCL and superoxide by human blood luekocytes and by mosue peritoneal macrophages, with an emphasis on the luekocyte-bacteria interactions in inflammation. JF - Cellular Chemiluminescence PB - CRC Press CY - Boca Raton Florida VL - II ER - TY - Generic T1 -

Oxygen Radicals, Proteinases and Polyanions Modulate Bacteriolysis by Leukocytes

T2 - Surface Structures of Microorganisms and Their Interactions with the Mammalian Host Y1 - 1987 A1 - Isaac Ginsburg A1 - M. Lahav AB - The mechanisms of biodegradation of microbial cell wall components is discussed. Employing Staphylococcus aureus as a model it is proposed that bacteriolysis following phagocytosis is mediated by the activation by leukocyte cationic proteins of the bacterial own autolytic wall enzymes. The role of lysozyme in bacteriolysis might not be due to its muramidase activity but to its cationic nature. A variety of sulfated polysaccharides, proteinases and oxygen radicals which might be present in inflamed tissues might inactivate the bacterial autolytic wall enzymes leading to the persistence of highly-phlogistic peptidoglycan-polysaccharide complexes within macrophages and to tissue damage. JF - Surface Structures of Microorganisms and Their Interactions with the Mammalian Host ER - TY - JOUR T1 -

Suppression of penicillin-induced bacteriolysis of staphylococci by some anticoagulants

JF - Journal of Antimicrobial Chemotherapy Y1 - 1987 A1 - J. Wecke A1 - E. Kwa A1 - Meir Lahav A1 - Isaac Ginsburg A1 - P. Giesbrecht AB - Heparinoids and related negatively-charged substances caused suppression of the penicillin-induced bacteriolysis of staphylococci and a higher viability rate. Furthermore, the penicillin-induced release of cell wall material was reduced by these substances. The main reason for this suppression of bacteriolysis was an inhibition of the activity of cell wall autolytic enzymes while the penicillin-specific perturbations of wall morphogenesis were not affected. VL - 20 IS - 1 ER - TY - JOUR T1 -

Phagocytosis of Candida albicans enhances malignant behavior of murine tumor cells

JF - Science Y1 - 1987 A1 - Isaac Ginsburg A1 - SE Fligiel A1 - RG, Kunkel A1 - BL, Riser A1 - James Varani AB - Murine tumor cells were induced to phagocytize either Candida albicans or group A streptococcal cells. The presence of microbial particles within the tumor cell cytoplasm had no effect on in vitro tumor cell growth. However, when Candida albicans-infected tumor cells were injected into syngeneic mice, they formed tumors that grew faster, invaded the surrounding normal tissue more rapidly and metastasized more rapidly than control tumor cells. Tumor cells infected with group A streptococcal particles did not grow faster or show increased malignant behavior. These data indicate that the in vivo behavior of malignant tumor cells can be modulated by microbial particles, which are often present in the microenvironment of the growing tumor. VL - 238 IS - 4833 ER - TY - JOUR T1 -

Poly L-histidine. A potent stimulator of superoxide generation in human blood leukocytes

JF - Inflammation Y1 - 1987 A1 - Isaac Ginsburg A1 - R Borinski A1 - M. Sadovnic A1 - Y Eilam A1 - K Rainsford AB - Poly-L-histidine (PHSTD) of molecular weight 26,000 induced the generation of large amounts of superoxide (O2-) and hydrogen peroxide (H2O2) in human neutrophils (PMNs). Despite its low solubility at neutral pH, PHSTD was bound very rapidly to the PMN surfaces. Maximal generation of O2- took place with 4-5 X 10(-6) M of PHSTD, starting after a lag of about 25 sec and proceeding for 15-17 min at a rate of 150 nmol/10(7) PMNs/min, suggesting that this polycation is one of the most potent stimulators of O2- generation known, PHSTD was found to be non-toxic for PMNs even at millimolar concentrations. Generation of O2- by PHSTD depended on extracellular calcium; it was inhibited by calcium channel blockers and by trifluoperazine, and it triggered a sharp rise in intracellular calcium as determined by the Quin 2 fluorescence technique. The generation of both O2- and H2O2 by PHSTD was partially inhibited by cytochalasin B or (CYB, CYE). On the other hand, CYB markedly enhanced the generation of both O2- and H2O2 following stimulation of PMNs either by PHSTD, polyarginine, histone, or by antibody-opsonized group A streptococci. Electron microscopic analysis and NBT reduction tests revealed that both PHSTD and PHSTD-opsonized streptococci were avidly phagocytosed by PMNs. Since CYB totally inhibited internalization of both PHSTD and the PHSTD-opsonized streptococci, it was suggested that these agents stimulated oxygen radical generation mainly on the leukocyte surfaces. Complexes (CX) formed between PHSTD and polyanethole sulfonate (a strong polyanion) or between histone and the polyanion mimicked immune CX in their ability to trigger the generation of large amounts of O2- which were inhibited by CYB. Generation of O2- and chemiluminescence either by PHSTD or by PHSTD-opsonized streptococci were markedly inhibited by poly-L-glutamate, suggesting that PHSTD acted as a cationic agent which interacted via electrostatic forces with some negatively charged sites in the leukocyte membrane. Generation of H2O2 by PHSTD was also markedly inhibited by deoxyglucose, KCN, DASA, as well as by the lipoxygenase inhibitors nordihydroguaiaretic acid, phenidone, and propylgallate. On the other hand, cyclooxygenase inhibitors such as aspirin, indomethacin, and piroxicam were inactive, suggesting that arachidonic acid metabolism via lipoxygenase pathway might have been involved in the activation by PHSTD of the NADPH oxidase in PMNs.(ABSTRACT TRUNCATED AT 400 WORDS) VL - 11 IS - 3 ER - TY - JOUR T1 -

Modulation of acute immune complex-mediated tissue injury by the presence of polyionic substances.

JF - The American Journal of Pathology Y1 - 1987 A1 - J. S. Warren A1 - P. A. Ward A1 - K. J. Johnson A1 - Isaac Ginsburg AB - Considerable attention has been focused on the role of electrostatic charge in the pathogenesis of immune complex-mediated tissue injury. The authors have examined the ability of cationic (histone, polyhistidine, polyarginine) and anionic (polyanetholsulfonate) polyelectrolytes to modulate acute immune complex-mediated tissue injury. Tissue injury elicited in rats by the reversed dermal Arthus reaction was increased 26-43% by addition of polyelectrolytes to antibody prior to its intradermal injection. Kinetic studies using 111In-labeled neutrophils indicated that the enhanced tissue injury was not the result of increased influx of neutrophils. Infusion of polyethylene glycol-conjugated superoxide dismutase prior to induction of the Arthus reaction resulted in 40-68% suppression of tissue injury. Concomitant in vitro functional studies (enzyme secretion, O-2 and H2O2 generation, and chemiluminescence) of rat neutrophils demonstrated that addition of polyelectrolytes to preformed immune complexes (IgG-bovine serum albumin) resulted in marked increases in O-2, H2O2, and chemiluminescence, but no increases in enzyme secretion, compared with neutrophils stimulated with immune complexes alone. The cationic polyelectrolytes did not alter the capacity of preformed immune complexes to activate complement in vitro. These studies suggest that both cationic and anionic polyelectrolytes can increase the pathogenic potential of immune complexes and that this modulation is, at least in part, mediated by enhanced generation of toxic oxygen-derived metabolites by neutrophils. VL - 128 IS - 1 ER - TY - JOUR T1 -

Cationic polyelectrolytes: a new look at their possible roles as opsonins, as stimulators of respiratory burst in leukocytes, in bacteriolysis, and as modulators of immune-complex diseases (a review hypothesis).

JF - Inflammation Y1 - 1987 A1 - Isaac Ginsburg AB - Voluminous literature exists today on the involvement of cationic polyelectrolytes (CPs) in host and parasite interrelationships. It has been shown that CPs of neutrophil (1-14), eosinophil (15, 16), macrophage (17), and platelet (18) origins function as distinct microbicidal agents. These probably constitute a "secondary" defense line supplementary to the main oxygen-dependent microbicidal systems of "professional" phagocytes. CPs have, however, also been implicated as modulators of blood clotting (19) and fibrinolysis (20), as a permeability-enhancing factors (21-23), in mast cell degranulation and in histamine release (24), as pyrogenic agents (25), as enhancers of complementmediated lysis (26), as modulators of PMN adherence (27-29) and chemotaxis (30-34), and as modulators of endocytosis (35-45) to list only several of the properties ascribed to these agents. Since the effects of CPs probably involve the interaction, through electrostatic forces, with negatively charged sites on target cells (36), it is plausible that the complex polyelectrolytic milieu found in infectious and inflammatory sites might function to modulate and regulate several important interactions of the host with invaders (46-48). Although CPs are primarily recognized for their distinct killing properties (10-13), recent studies have suggested that CPs might also be involved in a variety of additional biological, biochemical, and immunopathological phenomena which are seldom discussed in the general context of host and parasite interrelationships. The present review deals primarily with the possible involvement of CPs (1) in endocytosis and in cell adherence, (2) as activators of the respiratory burst in "professional" phagocytes, (3) as activators of the autolytic wall enzymes in certain microbial species and its relation to bacteriolysis and to the pathogenesis of chronic inflammation induced by bacterial cell walls, and (4) as agents capable of modulating the pathogenicity of immune complexes. It was felt that a discussion of these "other" properties of CPs is timely as it may shed a new light on the role of surface charge in cell-to-cell interactions as seen in inflammatory and infectious sites. VL - 11 IS - 4 ER - TY - JOUR T1 -

Polycationic agent facilitates

endocytosis of microorganisms by amoebae

JF - European Journal of Cell Biology Y1 - 1986 A1 - Isaac Ginsburg A1 - N. Mor A1 - M. Resnic A1 - H. Bercovier AB - Introduction Cationic polyelectrolytes play important roles in many biological systems. Histones [20] and cationic proteins of lysosomal origin [8, 18, 24, 25, 28, 33, 36, 37], both rich in arginine, and synthetic poly a-amino acids [3, 4, 5, 6, 23, 30] have been shown to be bactericidal and cytotoxic to a variety of bacteria and mammalian cells. In addition, these compounds modulate blood coagulation [30] and fibrinolysis [10]; agglutinate bacteria and mammalian cells [30]; modulate chemotaxis [16]; enhance adherence of mammalian cells to surfaces [26]; function as opsonins for phagocytosis by both "professional" and "nonprofessional" cells [3,5,6,17,27,28,34]; activate autolytic cell wall enzymes of Staphylococci [15]; and block Fe receptors for IgG upon certain group A Streptococci [14]. More recent studies have shown that histone-opsonized bacteria induced intense Iuminot- dependent chemiluminescence (LDCL) in human polymorphonuclear leukocytes (PMNs) and mouse peritoneal macrophages [In Furthermore, poly-i.-arginine collaborated with mixtures of lectins, calcium ionophore and the chemotactic peptide formyl-methionyl-Ieucyl-phenylalanine to induce synergistic LDCL and superoxide production in human PMNs [12,13]. Thus, arginine-rich polyelectrolytes appear to participate in many cellular functions related to host defenses against infection, presumably by mechanisms involving electrostatic interactions and ligand- receptor coupling phenomena. The objective of this present study was to investigate the possibility that arginine- rich polycations might facilitate the introduction of a variety of agents into eukaryotic cells. For this purpose, we have studied phagocytosis by Entamoeba histolytica of Candida albicans, and by Acanthamoeba palestinensis of Mycobacterium marinum. VL - 41 ER - TY - Generic T1 -

HOW ARE CELL-WALL COMPONENTS OF PATHOGENIC MICROORGANISMS DEGRADED

IN INFECTIOUS AND INFLAMMATORY SITES? FACTS AND MYTHS

T2 - Biological Properties of Peptidoglycan Y1 - 1986 A1 - Isaac Ginsburg AB - Introduction. Although a voluminous literature exists today which describes, in great detail, the role played by "professional" phagocytes and by serum components in the killing of pathogenic bacteria in vitro and in vivo (l-7) very surprisingly, however, little is actually known about the fate and mode of disposal of microorganisms once they had been rendered non-viable by the defence systems of the host. It is expected that the rich arsenal of lysosomal hydro- lases, including the key muralytic enzyme lysozyme (LYZ), present in leukocytes and in body fluids might be adequate to biodegrade the complex structures of the microbial cells. Paradoxically, however, the majority of bacteria are highly refractory to LYZ action. There is also some confusion in the literature concerning the distinction between bactericidal and bacteriolytic processes. It is conceivable that while a major degradation of microbial cell walls may be followed by a bactericidal reaction, the mere killing of bacteria either by oxygen radicals (2) or by complement-dependent cytlytic antibodies (7) may not necessarily be accompanied by a significant cell wall degradation. Many experimental models, with laboratory animals, have distinctly shown the persistence, for very long periods, of non-viable bacteria and of undergraded microbial cell wall components, within macrophages, in chronic inflammatory sites (8-l8). Thus, one should categorically differentiate between bactericidal and bacteriolytic phenomena. It is apparent, therefore, that mammalian tissues fail, for still not/fully known reasons, to biodegrade and eliminate microbial cell wall components. Peptidoglycan (PPG)-polysaccharide (PS) complexes derived from microbial cell walls possess distinct pathobiological and and pathophysiological properties (19-21). These include the capacity to activate the complement cascade and to generate chemotactic agents, to induce fever, to activate the respiratory burst in leukocytes and to modulate the immune responses (19-24), to mention only a few of the plethora of functions ascribed to PPG. These properties may also explain the very complex interrelationships which exist between the parasite and the host during microbial infections and the possible reasons for the development of certain post-infectious sequelae, which involve the prolonged persistence of bacterial cell wall components in tissues (10-15). JF - Biological Properties of Peptidoglycan ER - TY - JOUR T1 -

Inhibition of wall autolysis of staphylococci by sodium polyanethole sulfonate "liquoid"

JF - archives of Microbiology Y1 - 1986 A1 - J. Wecke A1 - Meir Lahav A1 - Isaac Ginsburg A1 - E. Kwa A1 - P. Giesbrecht AB - Liquoid (polyanethole sulfonate) was neither capable of influencing the growth nor the viability of staphylococci. But liquoid induced a suppression of the activity of different autolytic wall systems of normally growing staphylococci, i.e., autolysins which participate in cross wall separation as well as autolysins which are responsible for cell wall turnover. Additionally, the lysostaphin-induced wall disintegration of staphylococci was inhibited by liquoid. However, no indication could be found for a direct inhibition of lytic wall enzymes by liquoid; rather an interaction of liquoid with the target structure for the autolytic wall enzymes, the cell wall itself, was postulated. On the basis of the experimental data with the teichoic acid- mutant S. aureus 52A5 the sites of wall teichoic acid were supposed to be an important target for the binding of liquoid to the staphylococcal cell wall. VL - 144 IS - 2 ER - TY - CHAP T1 -

 

Streptococcal enzymes and virulence

T2 - Bacterial Enzymes and Virulence Y1 - 1985 A1 - Isaac Ginsburg ED - Ian Alan Holder JF - Bacterial Enzymes and Virulence PB - CRC Press CY - Boca Raton, FL ER - TY - CHAP T1 -

The Interaction of Staphylococcus aureus with Leukocytes in joint Lesions: An Ultrastructural Study

T2 - The Staphylococci (Zentralblatt Fur Bakteriologie, Mikrobiologie Und Hygiene : I. Abteiliung, Supplement 14) Y1 - 1985 A1 - Isaac Ginsburg A1 - Meir Lahav A1 - J. Goultchin A1 - Milu Sadovnik A1 - E. Kwa A1 - J. Wecke A1 - P. Giesbrech AB - Summary. Viable Staphylococcus aureus (strain Oxford beta lactamase negative) which had been cultivated either in the absence or presence of penicillin G (subinhibitory concentrations) were injected into the knee joint of adult rats. Tissue sections taken five days following the injections and analyzed by an electron microscope revealed the persistence of apparently intact cell walls within macrophages at the inflammatory sites. The data suggest that even under penicillin effect the macrophages were capable only of digesting the bacterial cytoplasmic constituents (plasmolysis) but failed to degrade the bacterial peptidoglycan. The possible role played by anionic polyelectrolytes, which accumulate at the inflammatory sites, in the inhibition of cell wall degradation by leukocytes in 1/it/0 and the role played by leukocyte factors in the activation of the bacterial own autolytic wall enzymes will be discussed. JF - The Staphylococci (Zentralblatt Fur Bakteriologie, Mikrobiologie Und Hygiene : I. Abteiliung, Supplement 14) PB - Gustav Fischer Verlag ER - TY - JOUR T1 -

Poly-L-arginine 'opsonizes' nuclei for phagocytosis by mouse fibroblasts

JF - IRCS Medical Science Y1 - 1985 A1 - G.E Hubner A1 - W.-H. Voigt A1 - H.D. Schlumberger A1 - Isaac Ginsburg VL - 13 IS - 10 ER - TY - JOUR T1 -

Superoxide generation by human blood leucocytes under the effect of cytolytic agents

JF - International journal of tissue reactions Y1 - 1985 A1 - Isaac Ginsburg A1 - Ruth Borinski A1 - M Pabst AB - Human blood leucocytes generate large amounts of superoxide following stimulation by polyarginine, polyanetholesulphonate and mixtures of a variety of soluble agents. Generation of O2-. by the various "cocktails" of soluble ligands is markedly enhanced by cytochalasins A, B, C, D, E and F. The efficiency of cytochalasin A is, however, at least 50-fold greater than that of the other cytochalasins. Leucocytes that have been treated for a few minutes with the cytolytic agents saponin, digitonin and lysolecithin undergo lysis and lose their superoxide-producing capacities, when a variety of soluble ligands are employed to stimulate superoxide production. A partial reactivation of the superoxide-producing capacities of the leucocytes can be achieved by adding NADPH. However, as the concentration of the cytolytic agents increases, reactivation of the cytochrome C reduction is less inhibitable by SOD, suggesting that cell lysis releases reductases of cytochrome C not connected with the superoxide-producing system of the leucocytes. Both saponin and digitonin can totally replace polyarginine as ingredients of the "cocktail," suggesting that these agents may also function as "priming agents" for superoxide production which can, however, further be enhanced by the addition of mixtures of soluble agents. Thus, leucocytes which had been lysed by membrane-active agents can nevertheless produce superoxide if adequate amounts of NADPH are added. VL - 7 IS - 2 ER - TY - JOUR T1 -

Persistence of staphylococcal cell-wall components in inflammatory sites may be due to the modulation by sulphated polyelectrolytes of autolytic wall enzymes: a working hypothesis

JF - International journal of tissue reactions Y1 - 1985 A1 - Isaac Ginsburg A1 - Meir Lahav A1 - Milu Sadovnik A1 - J. Goultchin A1 - J. Wecke A1 - P. Giesbrecht AB - The interaction of leucocytes with Staphylococcus aureus results in killing of the bacterial cells, but large portions of the bacterial cell walls persist apparently phagocytic cells for long periods. The mechanisms of biodegradation of staphylococci by leucocyte factors have shown that degradation of cell walls in vitro may be the result of the activation, by leucocyte kationic proteins, of the bacterial autolytic wall enzymes that are responsible for degrading the cell walls from within. This process is markedly inhibited by sulphated polysaccharides like dextran sulphate, by heparin, or by polyanetholesulfonate (liquoid). These anionic polyelectrolytes have also been shown to inhibit the lysis of staphylococci treated with bacteriolytic concentrations of penicillin G. Staphylococci injected intraarticularly into the knee joint of rats underwent massive plasmolysis, but structures compatible with cell walls (peptidoglycan) persisted within macrophages in the inflammatory sites, for long periods. It is postulated that the inability of leucocytes to degrade staphylococcal cell-wall components may be the result of the interference, by anionic polyelectrolytes likely to accumulate in the inflammatory sites, with the activation of the autolytic systems. Alternatively, anionic polyelectrolytes may coat the bacterial cells and interfere with the binding of the autolytic enzymes with their corresponding substrates. VL - 7 IS - 4 ER - TY - JOUR T1 -

NADPH and "cocktails" containing polyarginine reactivate superoxide generation in leukocytes lysed by membrane-damaging agents

JF - Inflammation Y1 - 1985 A1 - Isaac Ginsburg A1 - Ruth Borinski A1 - M Pabst AB - Human blood leukocytes generated large amounts of superoxide (O2-) following stimulation by certain "cocktails" of soluble agents consisting of poly-L-arginine (PARG), phytohemagglutinin, the chemotactic peptide formyl-methionyl-leucyl-phenylalanine and polyanethole sulfanote (liquoid). A variety of cytochalasins, which markedly boosted O2- generation by the soluble cocktails, markedly depressed luminol-dependent chemiluminescence (LDCL) which had been induced either by opsonized streptococci or by soluble agents. Glutathione, which totally reversed the inhibition of LDCL induced by cytochalasin A, failed to reverse the inhibition of LDCL induced by cytochalasin B. Generation of O2- by all the soluble agents employed, except PMA, was strongly inhibited either by the omission of extracellular calcium and magnesium or by treatment with the calcium blocker TMB-8. Generation of O2- was enhanced following stimulation of leukocytes with soluble agents if the cells had been exposed to slightly hypotonic buffers. Leukocytes, which had been preincubated for short periods (5 min) with PARG, saponin, digitonin, or lysolecithin (LL) and which lost their viability, and their O2- and LDCL-generating capacities following stimulation by soluble agents containing cytochalasin B, nevertheless regained these activities by the addition of NADPH. It is suggested that the lytic agents induced the leakage out of NADPH rather than acting as inactivators of the oxidase in the leukocyte membranes. Prolonged incubation of leukocytes with lytic agents failed to allow restoration, by NADPH, of the generation of SOD-inhibitable O2- generation. Since PARG acted both as a cytolytic agent and as a inducer of O2- generation, we postulate that lytic agents might also act as "primers" of the nascent membrane oxidase which could, however, be further potentiated and activated by soluble agents acting in "multiple hits," PARG could be totally replaced either by LL or by digitonin in the generation of O2- provided that both PHA and cytochalasin B were present in the reaction mixtures. We suggest that the various ingredients of the soluble "cocktails" may help to assemble components of the NADPH oxidase. Such an assembly and regulations are prerequisite for stimulation of the NADPH oxidase and the generation of oxygen radicals in leukocytes. VL - 9 IS - 4 ER - TY - JOUR T1 -

Chemiluminescence and superoxide generation by leukocytes stimulated by polyelectrolyte-opsonized bacteria. Role of histones, polyarginine, polylysine, polyhistidine, cytochalasins, and inflammatory exudates as modulators of oxygen burst

JF - Inflammation Y1 - 1985 A1 - Isaac Ginsburg A1 - Ruth Borinski A1 - D Malamud A1 - F Struckmeier A1 - V Klimetzek AB - Human blood leukocytes generate intense luminol-dependent chemiluminescence (LDCL) following stimulation by streptococci and by Gram negative rods which had been preopsonized by cationic polyelectrolytes (histone, poly L-arginine-PARG, poly L-histidine-PHSTD). Streptococci but not Gram negative rods or hyaluronic acid-rich streptococci (group C) also induced intense LDCL following opsonization with the anionic polyelectrolytes-dextran sulfate or polyanethole sulfonate (liquoid) suggesting that the outer surfaces of different bacteria bound anionic polyelectrolytes to different extents. Both normal and immune serum, synovial fluids and pooled human saliva inhibited the LDCL responses induced by streptococci preopsonized with poly cations. On the other hand, bacteria which had been first preopsonized by the various body fluids and then subjected to a second opsonization by cationic ligands ("sandwiches"), induced a very intense LDCL response in leukocytes. Streptococci which had been preopsonized by PARG, histone or by PHSTD also triggered superoxide generation by blood leukocytes, which was markedly enhanced by a series of cytochalasins. PHSTD alone induced the formation of very large amounts of superoxide. Paradoxically, the same concentrations of cytochalasins B or C which markedly boosted the generation of superoxide following stimulation of leukocytes with soluble or particulate ligands, had a strong inhibitory effect on the generation of LDCL. On the other hand cycochalasins failed to inhibit LDCL which had been induced by phorbol myristate acetate (PMA). Peritoneal macrophages which had been harvested from C. parvum-stimulated mice, generated more LDCL and superoxide following stimulation by PARG than macrophages obtained from proteose peptone-stimulated mice. Macrophages which had been activated either by proteose peptone or by C. parvum and cultivated for 2 hours on teflon surfaces, generated much more LDCL than macrophages which had been cultivated for 24 hours on teflon surfaces. Both cationic and anionic polyelectrolytes mimic the effects of antibodies as activators of the oxygen burst in blood leukocytes and in macrophages. Such polyelectrolytes can serve as models to further study leukocyte-bacteria interactions in infectious and inflammatory sites. VL - 9 IS - 3 ER - TY - CHAP T1 -

Antibiotics and Polyelectrolytes Modulate Bacteriolysis and the Capacity of Bacteria to Trigger an Oxygen Burst in Neutrophils

T2 - The Influence of Antibiotics on the Host-Parasite Relationship II Y1 - 1985 A1 - Isaac Ginsburg A1 - Ruth Borinski A1 - Milu Sadovnik A1 - Sara Shauli A1 - J. Wecke A1 - P. Giesbrecht A1 - Meir Lahav AB - The invasions of tissues by pathogenic microorganisms is followed by a sequence of events which culminate in phagocytosis and the intracellular killing of the ingested agents, by “professional” phagocytes [19]. It is also expected that the rich arsenal of hydrolases present in neutrophils and macrophages, including the muralytic enzyme lysozyme is adequate to degrade the complex architecture of the bacterial cells. Surprisingly, however, most pathogenic bacteria are extremely resistant to lysozyme action [14,21] and the fate of phagocytosed bacteria in vivo is not fully known [7,8,16,23]. The sequelae of the lack of bacterial degradation by leukocytes may be the “storage” of peptidoglycan-polysaccharide or peptidoglycan-lipopolysaccharide complexes within macrophages leading to the generation of granulomas and to the initiation of prolonged immune responses. This is pivotal to the initiation of immunopathological reactions [7, 8, 16, 23]. We have recently proposed [10, 11, 12, 13, 15, 29] that the biodegradation of certain microorganisms can be mediated through the activation, by cationic agents and phospholipases, of the bacterial own autolytic wall enzymes (suicidal phenomenon) which leads to the breakdown of the rigid cell walls. On the other hand, a variety of sulfonated anionic polyelectrolytes [11–13, 15] likely to be present in inflamed issues, may inhibit the biodegradation of the walls by the autolytic enzymes. JF - The Influence of Antibiotics on the Host-Parasite Relationship II PB - Springer Berlin Heidelberg VL - 2 ER - TY - JOUR T1 -

T-2 toxin effect on bacterial infection and leukocyte functions

JF - Toxicology and Applied Pharmacology Y1 - 1984 A1 - R. Yarom A1 - Y. Sherman A1 - R. More A1 - Isaac Ginsburg A1 - R Borinski A1 - B. Yagen AB - The effects of T-2 toxin on bacterial infection and leukocyte function and structure were examined in vivo and in vitro. Rats were innoculated with staphylococci after pretreatment with or without T-2 toxin. The T-2 pretreated rats failed to mount a cellular response to the bacteria. Blood and bone marrow cells were markedly suppressed by the T-2 toxin, the myeloid series being the most affected. In vitro studies with human leukocytes showed that small, nonkilling doses of T-2 toxin inhibited chemotaxis, chemiluminescence stimulated by bacteria, and phagocytosis of bacteria. It was concluded that this inhibition may contribute towards sepsis and rapid onset of death in T-2 toxin poisoning. VL - 75 IS - 1 ER - TY - JOUR T1 -

Poly-L-arginine and an N-formylated chemotactic peptide act synergistically with lectins and calcium ionophore to induce intense chemiluminescence and superoxide production in human blood leukocytes.

JF - Inflammation Y1 - 1984 A1 - Isaac Ginsburg A1 - R Borinski A1 - Meir Lahav A1 - Y, Matzner A1 - I, Eliasson A1 - P, Christensen A1 - D, Malamud AB - Various cationic polyelectrolytes (poly-alpha-amino acids and histones), lectins, the chemotactic peptide, f-methionyl-leucyl-phenylalanine (fMLP), the calcium ionophore A23187, and phorbol myristate acetate (PMA) were investigated regarding their capacity to induce luminol-dependent chemiluminescence (LDCL) and superoxide production by human blood leukocytes. Although when tested individually, poly-L-arginine (PARG), phytohemagglutinin (PHA), concanavalin A (Con A), or fMLP induced only a low to moderate LDCL response, very intense synergistic CL reactions were obtained by mixtures of PARG + PHA, PARG + Con A, PARG + PHA + fMLP, Ca2 + ionophore + PARG + PHA + fMLP, and PARG + PMA. The sequence of addition of the various agents to WBC in the presence of luminol absolutely determined the intensity of the LDCL signals obtained, the highest reactions being achieved when the WBC were preincubated for 2-3 min with A23187 followed by the sequential addition of fMLP, PARG, and PHA. These "multiple hits" induced CL reactions which were many times higher than those obtained by each factor alone. On the other hand, neither poly-L-lysine, poly-L-ornithine, poly-L-histidine, nor poly-L-asparagine, when employed at equimolar concentrations, cooperated efficiently with PHA and fMLP to trigger synergistic LDCL responses in leukocytes. Concomitantly with the induction of LDCL, certain ligand mixtures also triggered the production of superoxide. The LDCL which was induced by the "cocktail" of agents was markedly inhibited by sodium azide (93% inhibition), but to a lesser extent by catalase (10% inhibition) or by superoxide dismutase (20%-60% inhibition). On the other hand, scavengers of singlet oxygen and OH (sodium benzoate, histidine) did not affect the synergistic LDCL responses induced by these multiple ligands. Cytochalasin B also markedly inhibited the LDCL responses induced either by soluble stimuli or by streptococci preopsonized either with histone or with polyanethole sulfonate. The LDCL responses which were induced by mixtures of PARG and concanavalin A were also strongly inhibited by mannose, alpha-methyl mannoside, and poly-L-glutamic acid. The data suggest that the LDCL responses induced by the soluble ligands involved a myeloperoxidase-catalyzed reaction. The possible employment of "cocktails" of ligands to enhance the bactericidal effects of PMNs, macrophages, and natural killer cells on microbial cells and mammalian targets is discussed. VL - 8 IS - 1 ER - TY - Generic T1 -

The role of Ieucocyte and serum factors and of cationic polyelectrolytes in the lysis and

biodeg radation of Staphylococcus aureus: relation to the pathogenesis of staphylococcal infections

T2 - STAPHYLOCOCCI AND STAPHYLOCOCCAL INFECTIONS Y1 - 1983 A1 - Isaac Ginsburg A1 - Michael N. Sela A1 - N. Neeman A1 - Meir Lahav AB - INTRODUCTION. Although much is known today about the mechanisms by which virulent Staphylococcus aureus induce tissue lesions and cause clinical manifestations in mammals, our knowledge of the role played by “professional” phagocytes in host and parasite interrelationships in staphylococcal infections, is not fully understood. The extensive literature on staphylococci and their role in human disease has been the subject of several excellent comprehensive reviews (Whipple, 1965; Cohen, 1972; Jeljaszewicz, 1976). It is accepted that the interception of staphylococci by granulocytes (PMNs) takes place soon after the penetration of the cocci into the tissues. This involves the release of chemotactic factors, by the bacteria themselves (Pusell et al., 1975) or the activation, by staphylococcal factors, of chemotactic agents from complement (Ginsburg and Quie, 1980). Subsequent phagocytosis is markedly enhanced by opsonins (Koenig, 1972; Ekstadt, 1974), and in most cases the engulfed bacteria may be killed intracellularly by a variety of bactericidal agents generated by activated PMNs (Klebanoff, 1972). It is also suggested that certain lysosomal enzymes, which are released into the phagolysosome, may digest the staphylococcal cells (Cohn, 1963a; De Voe et al., 1973; Ginsburg and Sela 1976; Ginsburg, 1979) (see Sections II.B and VI). Several reports have, however, shown that intracellular staphylococci may sometimes survive within PMNs, where they multiply and eventually kill the cell (Koenig, 1972; Cohen, 1972; Pearce et al., 1976). Surprisingly, very little is known about the fate and mechanism of biodegradation of staphylococcal cell constituents, once they have been sequestered within the phagolysosomes of leucocytes. The importance of this field of research stems from the findings that non-biodegradable cell wall components of a variety of microbial species may persist within macrophges for prolonged periods, to trigger chronic infiammatory sequelae (Dannenberg, 1968; Kanai and Kondo, 1974; Ginsburg et al., 1975a; 1975b; 1976a; Ginsburg and Sela, 1976; Adams, 1976; Page et al., 1978; Ginsburg, 1979). The inability of “professional” phagocytes to degrade intracellular bacteria may be due (1) to the presence, on the surface of certain microorganisms, of shielding capsular material (Dossett et al., 1969; Smith, 1977; Wilkinson, et al., 1979; Densen and Mandell, 1980), (2) to the lack of fusion between lysosomes and phagosomes (Goren et al., 1976; Densen and Mandell, 1980), (3) to the production of leucocidins (Gladstone and Van Heyningen, 1957; Woodin, 1960; Ginsburg, 1970; Van Heyningen, 1970; Bernheimer. 1970; Ginsburg, 1972), (4) to the lack of adequate lysosomal enzymes capable of cleaving bacterial peptidoglycans (Dannenberg, 1968; Ginsburg, 1972; Ginsburg and Sela, 1976; Page et al., 1978; Ginsburg, 1979), or (5) to the presence, in serum and in inflammatory exudates, of agents which interfere with the interaction of bactericidal and bacteriolytic age with engulfed bacteria. These fields were comprehensively reviewed EW’ Jeljaszewicz, 1976; Smith, 1977; Ginsburg, 1979; and by Densen and Mandell, 1980. During the last 8 years our laboratory has been studying the host- and-parasite interrelationships in streptococcal and staphylococcal infections using biochemical, electron microscopical and tissue culture techniques. In particular we studied the mechanisms by which leu- cocytes and their isolated lysosomal agents bring about the degrada- tion of staphylococcal cell wall components, and the role which may be played by such degradation products in the initiation of chronic inflammation. The present report is an updated overview of these studies. JF - STAPHYLOCOCCI AND STAPHYLOCOCCAL INFECTIONS CY - London ER - TY - Generic T1 -

CATIONIC POLYELECTROLYTES ACTIVATE AUTOLYTIC WALL ENZYMES IN STAPHYLOCOCCUS

AUREUS: Modulation by anionic polyelectrolytes in relation to the survival

of bacterial constituents in tissues

T2 - The Target of Penicillin Y1 - 1983 A1 - Isaac Ginsburg A1 - Meir Lahav AB - Introduction. Although a wealth of knowledge exists today on the biochemical pathways of biosynthesis, turnover and autolysis of bacterial cell wall components in vitro (1, 2), surprisingly very little is actually known about the mechanisms of biodegradation of microbial constituents in_vivo. One should differentiate between bactericidal and bacteriolytic processes induced by leukocytes since killed, but non-degraded, microbial cells may persist within macrophages to trigger chronic inflammation (3, 4). The present communication further supports our contention (5, 6) that the degradation of microbial cell wall components by leukocytes may be due to activation, by leukocytic cationic proteins, of autolytic wall enzymes rather than to the direct cleavage of the cells by lysosomal hydrolases. The modulation of bacteriolysis by anionic polyelectrolytes will be described and discussed in relation to the pathogenesis of chronic inflammation and afequelae. JF - The Target of Penicillin ER - TY - Generic T1 -

INDUCED AUTOLYTIC WALL PROCESSES IN HEAT-INACTIVATED

STAPHYLOCOCCUS AUREUS

T2 - The Target of Penicillin Y1 - 1983 A1 - Meir Lahav A1 - Isaac Ginsburg AB - Introduction. In previous studies it could be shown that autolytic wall enzymes of bacteria can be activated by some cationic proteins (1). Recently we determination of firming our data lytic enzyme but obtained results from chemical and end group determination of the cleavage products from peptidoglycan confirming our data that even lysozyme acted not only as a muralytic enzyme but also as a cationic protein (2). In order to elucidate the mechanisms of the activation of autolytic wall processes by cationic proteins and of the direct respectively indirect muralytic actions of lysozyme we performed investigations on heated cells. JF - The Target of Penicillin ER - TY - JOUR T1 -

Lysis and biodegradation of microorganisms in infectious sites may involve cooperation between leukocyte, serum factors and bacterial wall autolysins: A working hypothesis

JF - European Journal of Clinical Microbiology Y1 - 1983 A1 - Isaac Ginsburg A1 - Meir Lahav AB - Although a voluminous literature exists today on the mechanisms by which "professional" leukocytes (granulocytes and maerophages) intercept with, engulf and eventually kill phagocytosed microorganisms ~ (1, 2), surprisingly very little is known about the mechanisms of degradation and elimination of bacteria from tissues. It is well established that phagocytic cells are endowed with numerous hydrolyric enzymes, including the key cell wall splitting enzyme-lysozyme, which can theoretically cleave, surface, eeU wall and cytoplasmic constituents of bacteria. Also, fresh mammalian sera are known to contain a complex mixture of heat-labile complement components (3) heat-stable lysozyme and platelet-derived cationic proteins (~-lysins) (4) which have been shown to kill and partially lyse certain microbial constituents. Surprisingly, however, the majority of virulent microorganisms are highly refractory to both leukocyte and serum lyric agents. Throughout this communication we shall use the general term bacteriolysis to denote the degradation of the cell walls, the outer membranes and the cytoplasmic constituents of bacteria. The term cell wall lysis will be used to describe the specific biochemical degradation of the bacterial peptidoglycan. This may also be accompanied by the rupture of the protoplast membrane and the release of cytoplasmic constituents. The inability of leukocyte and serum factors to induce bacteriolysis is linked to the presence, upon most bacterial surfaces, of'lipopolysaccharides, polysaccharides-teichoic complexes and certain lipids and waxes, which hinder the accessibility of the major cell wall splitting enzyme-lysozyme to the peptidoglycan (1). Once however this obstacle is overcome, the peptidoglycan ist degraded, and the protoplasts burst due to their high osmotic pressure, releasing degradation products of both cell wall and cytoplasmic constituents into the surrounding medium. The very extensive literature on these subjects has been recently summarized and reviewed (5-7). It has als0 been suggested that the process of killing and biochemical degradation of microbial constituents, either following phagocytosis or following treatment with fresh complement and lysozyme-sufficient serum are probably mediated by different mechanisms (6-8). While extensive loss of wall material and cytoplasmic entities is usually accompanied by a bactericidal reaction, the killing of bacteria either by the oxygen-dependent (9) or by the non-oxygen dependent bactericidal systems of leukocytes (5, 10) and serum (3), is not necessarily accompanied by a substantial bacteriolysis. The distinction between a bactericidal and a bacteriolyric process is important, in view of the observations that poorly degraded non-viable microbial constituents may persist for long periods both extracellularly and within phagocytic cells, to trigger and perpetuate chronic inflammatory sequellae (6, 7, 11-13). Furthermore, while degradation products of grampositive and acid-fast bacteria have been shown to be endowed with distinct pharmacological properties (14), to modulate the immune responses (15), to activate the complement cascade (16) and to be cytopathic for mammalian cells (14), the in vivo release of lipopolysaccharides of the outer membrane of gramnegative bacteria may result in severe coagulation defects (Shwartzman phenomenon) and in endotoxic shock (17). Poorly degraded cell wall components of bacteria have also been shown to be translocated within macrophages from one tissue site to another, thus contributing perhaps to the dissemination of granulomatosis (18-20). Although the nature of the biochemical pathways involved in bacterial biodegradation in tissues has not been fully elucidated, it has been recently suggested that a cooperation among leukocyte factors (21, 22), serum components (23), the bacterial own autolytic wall enzymes (21, 22) and certain antibiotics (24), may act in accord to induce a massive breakdown of cell wall and cytoplasmic constituents of bacteria. It is well established that the autolytic systems present in every bacterial cell, control cell division, the deposition of new cell wall material and the regeneration after treatment with certain antibiotics (25, 36). Autolytic enzymes have been isolated from many bacterial species and were found to possess muramidase, Nacetyl glucosaminidase, amidase and peptidase activities (25). It is also known that certain antibiotics, mainly of the penicillin and cephalosporin series, are capable of killing microorganisms, presumably by activating their autolytic wall enzymes (27). These intraceUular enzymes are thought to be controlled by endogenous lipid material (e.g.- phospholipids, lipoteichoic acid) (27). Thus, any agent present in leukocytes or in tissue fluids, which will disrupt the balance between autolytic enzymes and their naturally occurring inhibitors, may lead to the activation of autolysins, and concomitantly to the release of toxic bacterial agents. In view of the complex interrelationship which exist between bacteria and host factors in infectious and imflammatory sites, it was of interest to clarify some of the mechanisms and the factors involved in the biodegradation and persistence of microbial constituents in tissues. The following is an overview of our studies on this subject, employing staphylococci and streptococci as model systems, and using biochemical and electron microscopical techniques (28). The peptidoglycan of Staphylococcus aureus was labelled during the logarithmic phase of growth with 14C-N-acetylglucosamine. When such labelled cells were incubated for several hours at 37 ~ in acetate buffer pH 5.0, with small amounts of crude human leukocyte extracts or with more purified lysosomal extracts, a substantial amount of the radioactivity, associated with the cell walls was solubilized. Electron microscopical analysis of these reaction mixtures revealed the accumulation of cell wall fragments, and both amorphous and intact cytoplasmic constituents still retaining their typical morphologies (6, 7, 21, 22, 28, 29). Since the pH optimum for this reaction process was found to be on the acid side and compatible with the pH optima of many of the acid hydrolases known to be present in the leukocyte preparation (1) we postulated that the breakdown of the bacterial ceils was mediated by acid hydrolases. The findings, however, that heat treatment did not destroy the capacity of the leukocyte extracts to induce cell wall degradation, and that purified radiolabelled staphylococcal cell walls became completely refractory to the lytic effect of the extracts (21, 22), suggested that the wall degradation observed was probably not caused by the leukocyte hydrolases. Since leukocyte lysosomes are known to be rich in heat-stable argininerich bactericidal cationic proteins (LCP) (30) and in myeloperoxidase (MPO) (1) (also a cationic protein) it was reasonable to try and employ them, instead of the total leukocyte mixture, to lyse the staphylococci. Indeed we found that as little as 0.5-1/zg/ml of nuclear histone, poly-L-lysine, poly-L-arginine or MPO and 10-50/ag/ml of crystalline pancreatic ribonuclease or cytochrome C (all cationic in nature) were sufficient to induce massive loss of cell wall material from 108 log-phase staphylococci. Furthermore, small amounts of the membrane.damaging agents phospholipase A2, and polymyxins B and E were also capable of inducing cell wall lysis, as determined by the release of N-acetyl-glucosamine (8, 31-33). Since purified staphylococcal cell walls (devoid of cytoplasmic structures) were extremely refractory to any of the cationic polyelectrolytes or to the membrane-damaging agents, we postulated that perturbation of the staphylococcal membrane by these agents might have resulted in the activation of endogenous enzymes presumably associated with the autolytic systems (21, 22, 25, 26). As autolytic wall enzymes are known to be heat-labile (25, 26), it was of in,terest to try and reactivate the lytic process by the addition of freshly-harvested viable staphylococci (as donors of autolysins) to the heat killed radiolabeled staphylococci or to the purified labelled cell walls, in the presence of several of the cationic proteins or the membrane-damaging agents. Indeed, such mixtures resulted in a substantial loss of radiolabelled wall material. This process was completely blocked by anionic polyelectrolytes. We suggested, therefore, that the activators of autolysins interacted with the viable bacteria to release the autolytic enzymes, which in turn attacked and degraded the radiolabelled substances. Similar results were recently described with Bacillus subtilis (34). It has also been suggested that pneumococci, gonococci, meningococci, Streptococcus faecalis and perhaps listeriae may also likewise be degraded in vivo following the activation of their autolysins, and not through the direct action of lysosomal enzymes (28). Further experiments showed that Staphylococcus aureus, which had been cultivated in the presence of sub-inhibitory concentrations of penicillin G, became much more susceptible to wall lysis, following treatment with leukocyte extracts (24,35) suggesting a collaboration between/3-1actam antibiotics, leukocyte factors and bacterial autolysins in bacteriolysis (see 27). Other studies from our laboratory (23) have also shown that contrary to the accepted belief, both fresh and heat-treated human serum, when properly diluted, also lysed log-phase grampositive staphylococci and Streptococcus faecalis at pH 5.0. Since anionic polyelectrolytes also inhibited cell lysis induced by serum (23), and since heat-killed bacteria became resistant to lysis by serum, we postulated that, as in the case of leukocyte extracts, lysis was induced by a heat-stable factor, presumably ~-lysin of platelet origin (4) present in serum, which activated the autolytic systems of the bacteria. To further elucidate the mechanism of bacteriolysis, we have analyzed this process by electron microscopy. In collaborative studies with Prof. P. Giesbrecht and Dr. J. Wecke of the Robert Koch Institute in Berlin, we found (36) that a few hours after the addition of either crystalline lysozyme (500/ag) or pancreatic ribonuclease (50/ag/ml) to log-phase staphylococci, the first signs of cell damage could already be seen. These consisted of the formation of small, periodically-arranged lytic sites between the cell wall and the cytoplasmic membrane of the cross wall. This was followed by the formation of a distinct gap between the cell wall proper and the cytoplasmic membrane. The degradation of the peripheral cell wall continued to the opposite side of the cell, and extended gaps underneath the wall could be detected long before the cell wall itself was peeled off as large ribbons. The cross wall often appeared to be already disintegrated during the early phase of lysozyme or ribonuclease action. The release of the wall left apparently intact protoplasts, which still retained their original shape, and even the invagination of the cross walls were conserved. At this point over 70 % of the toal radioactivity associated with the cell wall was solubilized after three to four hours, and the radioactivity could not be sedimented at 100,000 • g suggesting the formation of solubilized peptidoglycan. Since lysozyme which had been heated to destroy its enzymatic activity still retained its ability to induce cell wall lysis, we postulated that lysozyme in this system did not act as an enzyme but as a cationic protein. Further studies from our laboratory (28) and in collaboration with the Robert Koch Institute (to be published in detail) have revealed that very similar ultrastructural changes in the staphylococci also took place following phagocytosis by mouse non-elicited macrophages in culture. On the other hand, although staphylococci, which had been injected into mouse or rat tissues, and which were phagocytosed by both PMNs and macrophages, underwent rapid loss of their cytoplasmic constituents, presumably by digestion with lysosomal hydrolases (37-39), no apparent damageto the cell walls was evident for many days, suggesting that the autolytic wall enzymes might have been inhibited. Since the degradation of the staphylococcal cell walls in vitro was completely inhibited by a variety of anionic polyelectrolytes like heparin, dextran sulfate, polyanethole sulfonate (a synthetic heparin), as well as by cationic polyelectrolytes like histones, poly-L-lysine, poly-L-ar~inine, etc., when used at 10-100 /ag/ml/10 ~ staphylococci (concentrations 10- 100 fold higher than those employed to activate the autolytic wall enzymes (see above), we also postulated that a delicate balance between activators and inhibitors may determine whether or not bacterial wall material may be degraded in tissue lesions in vivo (40,41). Finally, iecent studies (42) have also shown that high-molecular-weight degradation products of staphylococcal cell walls derived following treatment of the bacteria either in buffers (spontaneous wall lysis) or by small amounts of leukocyte extracts, were found to possess very strong chemot~ctic activities for PMNs in vitro, and to induce severe inflammatory lesions when injected intraarticularly to rats. Thus, it may be concluded that the fate of bacterial peptidoglycans in leukocytes in inflamed tissues may be dependent on the one hand on the availability of agents capable of activating autolytic wall enzymes in bacteria, and on the other hand on the presence in tissues of inhibitory substances (polyelectrolytes) which are capable of blocking bacteriolysis. It is, however, not aimed t9 rule out the possibility that other still unknown mechanisms may function in the complex milieu of inflammation, which may bring about the biodegradation of bacteria. The employment of certain antibiotics and other pharmacological agents, yet to be discovered, which will be capable of changing the balance between activators and inhibitors of autolytic enzymes, may contribute to a better understanding of the mechanisms involved in the survial and persistence of microbial agents in vivo. It is also obvious that the release of large quantities of microbial constituents following incomplete biodegradation may prove to be deleterious to tissues. Finally, our studies on staphylococci do not shed light on the mechanisms of biodegradation of other microbial species of medical imprtance, and is only a reflection of one possible mechanism, which may or may not be common to all microorganisms. VL - 2 IS - 3 ER - TY - JOUR T1 -

How are bacterial cells degraded by leukocytes in vivo? An enigma

JF - Clinical Immunology Newsletter Y1 - 1983 A1 - Isaac Ginsburg A1 - Meir Lahav AB - This year marks the centennial anniversary of Elie Metchnikoff's discovery of the pivotal role played by "professional" phagocytes in body defenses against invading microorganisms. His cellular theory dealt with the phagocytic events and the postphagocytic killing, and also alluded to the digestion of the internalized bacteria by the "cystases," later shown to be associated with the lysosomal apparatus of leukocytes. Fo date, despite the fact that numerous studies have described in great detail the mechanisms by which serum and leukocytes kill microorganisms (1, 8, 13, 24), surprisingly little is actually known about the biochemical pathways of degradation and mechanisms of disposal of microbial constituents once they have been sequestered within phagolysosomes (3, 9, 10, 13, 24). It is usually taken for granted that the numerous hydrolytic enzymes, including the key bacteriolytic enzyme lysozyme (muramidase), present in lysosomes of "professional" phagocytic cells [granulocytes or polymorphonuclear neutrophils (PMNs), and macrophages] are capable, (at least theoretically) of stripping off bacterial coats, thus exposing the peptidoglycan to cleavage by touramidase. Yet, the majority of pathogenic microorganisms are highly refractory to lysozyme action (9, 10, 17). One should also bear in mind that, while a massive breakdown of microbial cell walls eventually may lead to a bactericidal reaction, the mere killing of a microorganisms, either by leukocyte or by serum factors, may not necessarily be followed by a bacteriolytic reaction. The importance of elucidating the mechanism of microbial biodegradation in tissues stems from the observation that in many infectious diseases there is "storage" of nonbiodegraded microbial cell wall components within macrophages for long periods, which may be responsible for the perpetuation and propagation of chronic inflammatory sequelae and tissue destruction (10, 18). We have recently postulated (11, 14, 15) that bacteriolysis, and the biochemical degradation that ensues after bacteria have been attacked by serum or by leukocytes, may involve close cooperation among heat-stable serum factors, cationic proteins and phospholipase A2 of leukocytes, and heat-labile endogenous bacterial autolyric wall enzymes. This cooperation is affected markedly by anionic polyelectrolytes, likely to accumulate in inflammatory exudates, which may shut down autolysis and, thus, contribute to unfavorable postinfectious sequelae (10, 19). The present communication is a summary of efforts from our laboratory to gain insight into the mechanisms of lysis of Staphylococcus attreus, chosen as a model, by lysosomal enzymes of human blood leukocytes (3, 8-11, 14, 15, 19). VL - 4 IS - 11 ER - TY - CHAP T1 -

Effect of Antibiotics on the Lysis of Staphylococci and Streptococci by Leukocyte Factors, on the Production of Cellular and Extracellular Factors by Streptococci, and on the Solubilization of Cell-Sensitizing Agents from Gram-negative Rods

T2 - The Influence of Antibiotics on the Host-Parasite Relationship Y1 - 1982 A1 - Isaac Ginsburg A1 - Meir Lahav A1 - S. Bergner-Rabinowitz A1 - M. Ferne AB - Although much is known today about the mode of action of antibiotics on microorganisms, relatively little has been done to evaluate the possible collaboration between antibiotics and the host defenses in the containment and elimination of pathogens from host tissues. Since certain antibiotics are known to interfere with the biosynthesis of bacterial cellular and extracellular components, it is conceivable that such modified bacterial cells may be more readily intercepted, killed, and eventually digested by professional phagocytes. On the other hand, certain antibiotics may have adverse effects on mammalian cells by interfering with their normal metabolism and subsequently with their antimicrobial functions. Although the role of bacteriolysis in host and parasite interrelationships has been recognized for over a decade, this field of research has surprisingly been almost totally neglected. The importance of understanding the mechanisms of biodegradation of microbial cells in vivo stems from the recognition that the inability of the enzymes of the host to degrade the rigid cell wall of microorganisms is a contributory factor to the formation of chronic granulomatous responses, and to the destruction of tissues [1, 6, 16, 17, 22, 30]. Thus, any antibiotics which will collaborate with leukocytes or with serum factors in the elimination of bacterial constitutents from infected tissues may greatly contribute to the well-being of the individual. JF - The Influence of Antibiotics on the Host-Parasite Relationship ER - TY - JOUR T1 -

Effects of subminimal inhibitory concentrations of chloramphenicol, erythromycin and penicillin on group A streptococci

JF - European Journal of Clinical Microbiology Y1 - 1982 A1 - J. Michel A1 - M. Ferne A1 - R Borinski A1 - Z. Kornberg A1 - S. Bergner-Rabinowitz A1 - Isaac Ginsburg AB - Group A streptococci strains were grown in broth containing subminimal inhibitory concentrations of chloramphenicol, erythromycin and penicillin, and tested for possible changes in colonial morphology, activity and amount of cellular and extracellular components. The following components were tested: T protein, M protein, opacity factor, lipoteichoic acid, hyaluronic acid, streptolysin S, streptolysin O, DNase, hyaluronidase and NADase. Sub-MICs of these drugs produced variable changes in the bacteria. They increased the amount of hyaluronic acid and hyaluronidase, decreased the amount of M protein, and enhanced phagocytosis and the release of lipoteichoic acid. The results indicate that sub-MICs of chloramphenicol, erythromycin and penicillin may affect the pathogenicity and toxinogenicity of group A streptococci. VL - 1 IS - 6 ER - TY - JOUR T1 -

Isolation and characterization of rat skeletal muscle and cytoplasmic actin genes

JF - Proceedings of the National Academy of Sciences of the United States of America Y1 - 1982 A1 - U. Nudel A1 - D. Katcoff A1 - R. Zakut A1 - M. Shani A1 - Y. Carmon A1 - M. Finer A1 - H. Czosnek A1 - Isaac Ginsburg A1 - D. Yaffe AB - Southern blots of rat genomic DNA indicate the existence of at least 12 EcoRI DNA fragments containing actin gene sequences. By using specific probes and stringent conditions of hybridization, it was found that only one of these fragments contains sequences of the skeletal muscle alpha-actin gene. Recombinant bacteriophages originating from eight different actin genes were isolated from rat genomic DNA libraries. One of them, Act 15, contains the skeletal muscle actin gene. Another clone, Act I, contains a gene coding for a cytoplasmic actin, identified tentatively as the beta-actin gene. Both genes have a large intron very close to the 5' end of their transcribed region, followed by several small introns. DNA sequence analysis and comparison with the available data on actin genes in other organisms indicated an interesting relationship between the positions of introns and the evolutionary relatedness. Several intron sites are conserved from at least the echinoderms to the vertebrates; others appear to be present in some actin genes and not in others. VL - 79 IS - 9 ER - TY - JOUR T1 -

The role of cationic proteins and anionic polyelectrolytes in the control of bacterial infections. Cooperation between PMNS and macrophages

JF - International Journal of Immunopharmacology Y1 - 1982 A1 - Isaac Ginsburg A1 - Meir Lahav AB - It is postulated that lysosomal enzymes of leukocytes are capable of breaking down bacterial constituents and to cause bacteriolyasis. Studies from our laboratory have shown that radiolabled staphylococci (log-phase) arm readily lysed by leukocyte extracts at pH 5.0. On the other hand, old cells or heat-killed young cells are resistant degradation. The leukocytes extracts can be affectively replaced by cationic proteins as well as by membrane-damaging agents (phospholipase A2, polymaxins). Studies on the mechanisms of bacteriolysis have suggested that the cationic proteins act by activating the bacterial autolytic enzymes leading to bacteriolysis. This proces can be inhibited by a series of anionic polalalectrolytes likely to preent in inflammation, presumably by inactivating autolytic enzymes. The cooperation between PHNs and macrophages in bacteriolysis and control of bacterial growth by polalalectrolytes will be discussed in relation to the phatogenesis of the infection and inflammation. VL - 4 IS - 4 ER - TY - JOUR T1 -

Cationic Polyelectrolytes and Leukocyte Factors Function as Opsonins, Triggers of Chemiluminescence and Activators of Autolytic Enzymes in Bacteria: Modulation by Anionic Polyelectrolytes in Relation to Inflammation

JF - Advances in experimental medicine and biology Y1 - 1982 A1 - Isaac Ginsburg A1 - Meir Lahav A1 - Mina Ferne A1 - Sybille Müller AB - Both antibodies and complement components are essential for successful phagocytosis of many virulent microorganisms (1,2). Although the mechanisms by which opsonins promote particle uptake are not fully understood, it has been suggested that both electrostatic and hydrophobic forces act in concert with specific receptors for Fc and C3b to facilitate interiorization of particles (2,3). In the case of group A streptococci, opsonization by immunoglobulins abolishes the anti-phagocytic properties of the M-antigen (4,5). Since one mechanism by which opsonins may act is to decrease repulsion forces between negative charges present on the surface of the particle and phagocyte, cationic ligands may function as effective opsonins (6–11). In addition, cationic substances may participate in bacteriolysis. We recently suggested (11) that the breakdown of bacterial cells following phagocytosis is mediated indirectly by leukocyte cationic proteins and phospholipases which activate autolytic enzymes and not by lysosomal enzymes directly. VL - 155 ER - TY - JOUR T1 -

Phospholipids inhibit cytotoxic effects of Actinobacillus actinomycetemcomitans leukotoxin on human polymorphonuclear leukocytes

JF - Inflammation Y1 - 1982 A1 - Isaac Ginsburg A1 - CC Tsai A1 - SM, Wrenn A1 - NS, Taichman AB - Isolated human peripheral blood neutrophils were exposed to sonic extracts of Actinobacillus actinomycetemcomitans. Such bacterial preparations contain a potent leukotoxin which rapidly kills the leukocytes as reflected by cellular uptake of trypan blue, extracellular release of lactate dehydrogenase, or discharge of 51Cr from pre-labeled cells. Exogenous phospholipids with a glycerol skeleton esterified by fatty acids or positively charged liposomes inhibited cytotoxic phenomena. The data suggest that cell damage may involve the interaction of leukotoxin with phospholipids in the neutrophil cell membrane and that exogenous lipids either compete for or sterically block binding of the leukotoxin to these moieties in the membrane. VL - 6 IS - 4 ER - TY - JOUR T1 -

Modulation of human lymphocyte transformation by bacterial products and leukocyte lysates

JF - Inflammation Y1 - 1982 A1 - Michael N. Sela A1 - Isaac Ginsburg A1 - T. Dishon A1 - Zvia Duchan A1 - AA Garfunkel AB - Blast transformation of human peripheral blood lymphocytes by PHA is shown to be modulated by lipoteichoic acid (LTA) of Streptococcus mutans, by a cell-sensitizing factor of Actinomyces viscosus, as well as by a frozen and thawed extract of human leukocytes (LE). While small amounts of LE (5-50 micrograms/10(6) cells) significantly enhanced PHA-induced transformation, higher amounts showed a lesser effect on the blastogenic response. Both LTA and the A. viscosus extract did not cause any lymphocyte blastogenic effect when used alone. On the other hand LTA had an inhibitory effect and the A. viscosus extract had an enhancing effect when lymphocytes were pretreated by these agents and then exposed to PHA. VL - 6 IS - 1 ER - TY - JOUR T1 -

Cell wall degradation of Staphylococcus aureus by lysozyme

JF - archives of Microbiology Y1 - 1982 A1 - J. Wecke A1 - Meir Lahav A1 - Isaac Ginsburg A1 - P. Giesbrecht AB - In contrast to former findings lysozyme was able to attack the cell walls of Staphylococcus aureus under acid conditions. However, experiments with 14C-labelled cell walls and ribonuclease indicated that, under these conditions, lysozyme acted less as an muralytic enzyme but more as an activator of pre-existing autolytic wall enzymes. Electron microscopic studies showed that under these acid conditions the cell walls were degraded by a new mechanism (i.e. "attack from the inside"). This attack on the cell wall started asymmetrically within the region of the cross wall and induced the formation of periodically arranged lytic sites between the cytoplasmic membrane and the cell wall proper. Subsequently, a gap between the cell wall and the cytoplasmic membrane resulted and large cell wall segments became detached and suspended in the medium. The sequence of lytic events corresponded to processes known to take place during wall regeneration and wall formation. In the final stage of lysozyme action at pH 5 no cell debris but "stabilized protoplasts" were to be seen without detectable alterations of the primary shape of the cells. At the same time long extended ribbon-like structures appeared outside the bacteria. The origin as well as the chemical nature of this material is discussed. Furthermore, immunological implications are considered. VL - 131 IS - 2 ER - TY - JOUR T1 -

CATIONIC POLYELECTROLYTES, LIQUOID AND LEUKOCYTE EXTRACT MODULATE THE BINDING OF IgG TO GROUP A STREPTOCOCCAL Fc-RECEPTORS

JF - APMIS- Acta Pathologica Microbiologica Scandinavica Y1 - 1982 A1 - Isaac Ginsburg A1 - POUL CHRISTENSEN A1 - INGVAR ELIASSON A1 - CLAËS SCHALÉN AB - Various polyelectrolytes were investigated regarding their capacity to inhibit the binding of human IgG to Fc-receptors on group A streptococci, type M1. Of cationic substances, protamine and arginine-rich histone inhibited significantly, while lysine-rich histone, concanavalin A, lysozyme, polymyxin B, ribonuclease and tuftsin did not. Of anionic materials, liquoid was inhibitory, in contrast to chondroitin sulphate, dextran sulphate, DNA and heparin. Washing experiments showed that the inhibition was caused by binding of the polyelectrolytes to the streptococci. The finding that heated IgG inhibited the binding of histone to the streptococci also indicated a close relation between the binding sites for these compounds. Diffusion-in-gel experiments with alkaline extract of M1 demonstrated that the substances blocking the IgG Fc-receptor were bound to polyglycerophosphate, suggesting that the inhibition of the IgG uptake was due to interaction with lipoteichoic acid. Leukocyte and platelet extracts could modify the binding of IgG, probably by an enzymatic digestion of the receptors. The arginine-rich histone was also capable of inhibiting the binding of IgG to type M15 group A streptococci and to one group G strain. However, the polyelectrolytes had no effect on the binding of IgG to Staphylococcus aureus or of IgA to type 4 group A streptococci. VL - 90B IS - 1-6 ER - TY - JOUR T1 -

Bacteria and zymosan opsonized with histone, dextran sulfate, and polyanetholesulfonate trigger intense chemiluminescence in human blood leukocytes and platelets and in mouse macrophages

JF - Inflammation Y1 - 1982 A1 - Isaac Ginsburg A1 - R. Borinsky A1 - M. Lahav A1 - K.E. Gillert A1 - S. Falkenberg A1 - M. Winkler A1 - S. Muller AB - Human blood leukocytes and platelets and mouse peritoneal macrophages emit very rapid and very intense Luminol-dependent chemiluminescence (CL) signals when treated with streptococci, staphylococci, or with zymosan, which have been preopsonized with arginine-rich histone, dextran sulfate or polyanetholesulfonate (liquoid). Liquoid alone at 10-30 micrograms/2 X 10(5) leukocytes also triggers intense CL responses in the absence of a carrier. Strong CL can also be triggered, and at the same levels, when the various polyelectrolytes are simply mixed with the bacteria or zymosan and added to the leukocyte suspensions. The CL responses induced by the polyelectrolyte-bacteria complexes greatly exceed those triggered in leukocytes by antibody-complement-coated particles. Liquoid also shows a unique property of markedly augmenting CL signals which have already been induced by other ligand-coated bacteria or zymosan particles. Streptococci and staphylococci were found to be much superior to zymosan, Gram-positive bacilli, or E. coli as carriers for the various polyelectrolytes in the CL reaction. Neither protamine sulfate, lysozyme, myeloperoxidase, crystalline ribonuclease (all cationic in nature), chondroitin sulfate, heparin, nor alginate sulfate acted as ligands for triggering CL, when used to opsonize bacteria or zymosan. The induction of CL in blood leukocytes by the various ligand-coated bacteria is markedly inhibited by azide, KCN catalase, aminotriazole, and EDTA, agents known to inhibit the production of oxygen radicals following stimulation of leukocytes by opsonized bacteria. Two children diagnosed for chronic granulomatous diseases (CGD) of childhood and an apparently healthy sister of one of the male patients completely failed to respond with CL either to the polyelectrolyte-bacteria complexes, liquoid or antibody-coated bacteria and zymosan. It is proposed that liquoid be employed for the rapid screening of defects in certain oxygen-dependent metabolic processes in both PMNs and macrophages. It is also suggested that polyelectrolytes like the ones described in this study may markedly enhance the bactericidal properties of leukocytes and macrophages towards both extracellular and intracellular microorganisms and may perhaps also augment the tumoricidal effects of activated macrophages. VL - 6 IS - 4 ER - TY - JOUR T1 -

Effect of leukocyte hydrolases on bacteria XVI. Activation by leukocyte factors and cationic substances of autolytic enzymes in Staphylococcus aureus

JF - Inflammation Y1 - 1982 A1 - Isaac Ginsburg A1 - Meir Lahav A1 - P. Giesbrech AB - Effect of leukocyte hydrolases on bacteria XVI. Activation by leukocyte factors and cationic substances of autolytic enzymes in Staphylococcus aureus: modulation by anionic polyelectrolytes in relation to survival of bacteria in inflammatory exudates. The mechanisms involved in the activation of autolytic enzymes in Staphylococcus aureus, by leukocyte extracts, cationic proteins, phospholipase A2, amines, and membrane-damaging agents was studied in a resting cell system as well as by growing staphylococci. The bacteria were labeled with [14C]N-acetylglucosamine and were subjected to a variety of agents either in 0.1 M acetate buffer, pH 5.0, or in phosphate buffer, pH 7.4. While intact log-phase cultures were found to undergo partial autolysis at pH 5.0 and almost complete lysis at pH 7.4, both heat-killed bacteria and bacterial cell walls were completely resistant to autolysis in buffers. Autolysis at pH 5.0 can be further activated by leukocyte extracts, nuclear histone, crystalline ribonuclease, egg-white and human lysozyme, phospholipase A2, as well as by spermine, spermidine, and polymyxins B and E. The addition of viable log-phase bacteria to radiolabeled heat-killed staphylococci or to radiolabeled cell walls which had been cleaned off autolytic enzymes resulted in degradation of the radiolabeled targets. The data suggest that the various inducers of autolysin activation caused leakage of autolytic enzymes from the intact bacteria which attacked the depolymerized the bacterial cell walls. Anionic polyelectrolytes like heparin, dextran sulfate, suramine, polyglutamic acid, and liquid (polyanethole sulfonic acid) markedly inhibited both spontaneous and induced lysis. Staphylococci which had grown in the presence of anionic polyelectrolytes became highly resistant to lysis triggered by any of the inducers of autolysis. Since inflammatory exudates are known to be rich in anionic polyelectrolytes, it is suggested that the prolonged survival of intact bacterial cells in such a milieu may be due to the inactivation of autolytic enzymes. It is also postulated that the degradation of certain bacterial species following phagocytosis or extracellular degradation may not be the result of the action of hydrolytic enzymes but rather the result of activation by leukocyte factors of autolytic enzymes which lead to bacteriolysis. VL - 6 IS - 3 ER - TY - JOUR T1 -

Mechanisms of biodegradation of staphylococci by leukocyte factors and its modulation 

JF - Zentralblatt fur Bakteriologie Mikrobiologie und Hygiene Y1 - 1981 A1 - Isaac Ginsburg A1 - N. Ne'eman A1 - Meir Lahav A1 - Michael N. Sela A1 - PG. Quie AB - Mechanisms of biodegradation of staphylococci by leukocyte factors and its modulation by serum proteins, inflammatory exudates, polyelectrolytes, antibiotics and by lipoteichoic acid: Relation to chemotaxis and to the survival of bacteria in inflammatory sites After phagocytosis of opsonized and non-opsonized bacteria by phagocytes, there is fusion of lysosomes discharge of lysosomal factors into phagosomes and activation of metabolic pathways leading to the generation of hydrogen peroxide, singlet oxygen, and other oxygen radicals, and death of the engulfed bacteria. Although much is known today about the mechanism by which phagocytes kill bacteria following phagocytosis, very little is known about the mechanisms of biodegradation of the engulfed bacteria. Biodegradation of bacteria within PMN involves action of lysosomal enzymes, neutral protease collagenases and proteases as well as reactive oxygen radical and release of these products from phagocytes may lead to destruction of host tissue. The propagation of chronic inflammatory sequellae following infections with staphylococci may also be mediated by delayed and immediate hypersensitivity reactions. Degradation of products of microbes also may diffuse into tissue and the chemotactic properties of these exudates attracts more phagocytic cells. Inflammatory exudates induced by bacterial infections are rich in acid and neutral hydrolases of leukocyte origin as well as bacterial products. The purpose of the present communication is to summarize several years of investigation of the pathogenesis of staphylococcal lesions with emphasis on the role played by anionic and cationic polyelectrolytes and degradation products of bacteria in the modulation of leukocyte-bacteria interactions (10, 14). VL - 251 IS - Suppl. 10 ER - TY - JOUR T1 -

Modulation of Actinobacillus actinomycetemcomitans (Aa) leukotoxic activity by phospholipids

JF - Journal of Dental Research Y1 - 1981 A1 - P. Baehni A1 - C.-C. Tsai A1 - Isaac Ginsburg VL - 60 IS - Spec A ER - TY - JOUR T1 -

 

Role of leukocyte factors and cationic polyelectrolytes in phagocytosis of group a streptococci andCandida albicans by neutrophils, macrophages, fibroblasts and epithelial cells

JF - Inflammation Y1 - 1981 A1 - Isaac Ginsburg A1 - Michael N. Sela A1 - Abraham Morag A1 - Zohar Ravid A1 - Zvia Duchan A1 - Mina Ferne A1 - Sonia Rabinowitz-Bergner A1 - Peter Page Thomas A1 - Philip Davies A1 - John Niccols A1 - John Humes A1 - Robert Bonney AB - A variety of cationic polyelectrolytes opsonized group A streptococci andCandida albicans to phagocytosis by human polymorphonuclear leukocytes and by mouse peritoneal macrophages. The most potent opsonins for streptococci were specific antibodies supplemented with complement, nuclear histone, polylysine, polyarginine, ribonuclease, leukocyte lysates, leukocyte cationic protein and, to a lesser extent, lysozyme and myeloperoxidase. Histone, RNAse, leukocyte extracts, and platelet extracts also functioned as opsonins for phagocytosis of streptococci in the peritoneal cavity, where phagocytic indices, higher than those obtained for the in vitro phagocytosis, were obtained. Fresh serum, polylysine, polyarginine, and nuclear histone acted as good opsonins forCandida, but none of the other factors tested were active. In order for the cationic proteins and leukocyte extracts to function as opsonins, they must be present on the particle surface. These agents were poor opsonins when applied on the macrophages. Nuclear histone, polylysine, polyarginine, and fresh human serum also functioned as good opsonins for the uptake ofCandida by mouse fibroblasts. On the other hand, none of the other substances which opsonized streptococci were effective withCandida. The phagocytic capabilities of fibroblast polykaryons were much higher than those of ordinary spindle-shaped mouse fibroblasts. Histone also functioned as a good opsonic agent for the uptake ofCandida by human fibroblasts, HeLa cells, epithelial cells, monkey kidney cells, and rat heart cells. On the other hand, neither leukocyte extracts nor ribonuclease LCP or MPO functioned as opsonins for these mammalian cells.Candida, taken up by fibroblasts, were present within tight phagosomes, but no fusion of lysosomes with the phagosome occurred. A small proportion of the internalized yeast cells underwent partial plasmolysis, but little damage to the rigid cell walls was observed within 24–48 h of internalization. Phagocytosis of streptococci andCandida by macrophages and the uptake ofCandida by fibroblasts were both strongly inhibited by liquoid (polyanethole sulfonic acid sodium salt). This anionic polyelectrolyte also markedly inhibited the release ofN-acetylglucosaminidase from macrophages without affecting cell viability (LDH release). Hyaluronic acid, DNA, and dextran sulfate markedly inhibited the uptake of histone-coated particles by macrophages. On the other hand, hyaluronic acid and DNA enhanced the uptake ofCandida by fibroblasts. The effect of these anionic polyelectrolytes on phagocytosis of serum-opsonized particles by macrophages was not consistent. While in some experiments it blocked phagocytosis, in others it either had no effect or even enhanced the uptake of the particles. Phagocytosis of microorganisms by “nonprofessional” phagocytes like fibroblasts and the paucity in these cells of hydrolases capable of breaking down microbial cell wall components may contribute to the persistence of non-biodegradable components of bacteria in tissues and to the perpetuation of chronic inflammatory sequellae. Cationic polyelectrolytes may also prove important as “helper” opsonins and as agents capable of enhancing the penetration into cells of both viable and nonviable particles, genetic material, and drugs. VL - 5 IS - 4 ER - TY - JOUR T1 -

Bacteriolytic activity of human gingival exudate

JF - Inflammation Y1 - 1980 A1 - Michael N. Sela A1 - G. Natan A1 - Meir Lahav A1 - Isaac Ginsburg A1 - T. Dishon AB - We investigated the bacteriolytic activity of gingival crevicular fluid (CF) on 14C-labeled Streptococcus faecalis, Streptococcus mutans, Staphylococcus aureus, and on whole dental plaque. CF was collected from 100 healthy donors pooled and centrifuged at 200 g. CF supernate and a frozen and thawed extract of the pellet were interacted with the different bacterial strains, while Streptococcus faecalis and Staphylococcus aureus released 60% and 75% of the radioactive label, only 38% of it was solubilized from Streptococcus mutans, following their incubation with the CF supernate. The findings agreed with results obtained by interacting bacteria with a frozen and thawed lysate of human peripheral blood leukocytes. On the other hand, extracts from frozen and thawed CF pellet were inactive. Further, lipoteichoic acid and lipopolysaccharide were released by CF from Gram-positive and Gram-negative bacteria, respectively. The role of bacteriolytic factors, present in CF, as a result of the interaction between microorganisms and leukocytes at inflammatory sites is discussed. VL - 4 IS - 2 ER - TY - JOUR T1 -

Effect of antibiotics and metabolic inhibition on the enzymatic release of lipopolysaccharides from gram-negative bacteria

JF - Israel Journal of Medical Sciences Y1 - 1980 A1 - Mina Ferne A1 - D. Cohen A1 - S. Bergner-Rabinowitz A1 - Isaac Ginsburg VL - 16 IS - 1 ER - TY - JOUR T1 -

Streptococcal and staphylococcal arthritis

JF - Agents Actions (Inflammation Research Y1 - 1980 A1 - Isaac Ginsburg A1 - J. Goultchin A1 - A. Stabholtz A1 - N. Neeman A1 - Meir Lahav A1 - L. Landstrom A1 - PG. Quie AB - Streptococcal and staphylococcal arthritis: can chronic arthritis in the human be caused by highly chemotactic degradation products generated from bacteria by leukocyte enzymes and by the deactivation of leukocytes by inflammatory exudates, polyelectrolytes, leukocyte hydrolases and by cell sensitizing agents derived from bacteria? VL - 7 ER - TY - JOUR T1 -

Modulation of human polymorphonuclear leukocyte chemotaxis by leukocyte extracts, bacterial products, inflammatory exudates, and polyelectrolytes

JF - Inflammation Y1 - 1980 A1 - Isaac Ginsburg A1 - PG Quie AB - Human polymorphonuclear leukocytes (PMN) chemotaxis was tested during exposure to leukocyte and platelet extracts, a variety of polyelectrolytes, inflammatory exudates, and bacterial products. The chemoattractants employed were either zymosan-activated serum or supernatant from autolyzed Staphylococcus aureus. Chemotaxis to both chemoattractants was markedly inhibited by leukocyte and platelet extracts; inflammatory exudates; anionic polyelectrolytes, DNA, hyaluronic acid, liquoid; and by cationic polyelectrolytes, histone, protamine base, protamine sulfate, and myeloperoxidase. Inhibition was also found with elastase, collagenase, pepstatin, and epsilon-amino-caproic acid. Bacterial products, such as lipoteichoic acid and lipopolysaccharides, and extracts of human dental plaque inhibited chemotaxis. No inhibition of chemotaxis was observed with heparin (< 10 micrograms/ml), chondroitin sulfate, phosphatidylethanolamine and phospatidylserine. Indeed, chondroitin sulfate markedly enhanced chemotaxis and antagonized the inhibitory effect of leukocyte or platelet extract. None of the agents employed was toxic to PMN as judged by trypan blue exclusion. These observations suggest that cationic polyelectrolytes and inflammatory exudates influence PMN surfaces, modifying interaction with chemoattractants. Assessment of the role of PMN chemotaxis in host defense against microbial invaders requires evaluation of the response in the presence of agents likely to be present in inflamed tissues. VL - 4 IS - 3 ER - TY - JOUR T1 -

Effect of leukocyte hydrolases on bacteria. XIII.

JF - Inflammation Y1 - 1979 A1 - Meir Lahav A1 - N. Ne'eman A1 - Michael N. Sela A1 - Isaac Ginsburg AB - Effect of leukocyte hydrolases on bacteria. XIII. Role played by leukocyte extracts, lysolecithin, phospholipase a2, lysozyme, cationic proteins, and detergents in the solubilization of lipids from Staphylococcus aureus and group A streptococci: relation to bactericidal and bacteriolytic reactions in inflammatory sites The bactericidal and bacteriolytic effects of lysolecithin (LL) and egg-white lysozyme (LYZ) on Staph. aureus and group A streptococci and the solubilization of phospholipids from the bacterial membranes by these agents was studied. Low concentrations of lysolecithin (1--10 microgrames/ml) are highly bactericidal for Steph. aureus and group A streptococci, but induce neither bacteriolysis nor solubilization of a substantial amount of membrane phospholipids. On the other hand, while LL at greater than 50 micrograms/ml causes substantial lipid release, a combination of LL and LYZ is absolutely needed to solubilize lipids from streptococci. This combination is, however, not bacteriolytic for this microrganism. The solubilization of lipids from staphylococci by LL is much faster than that induced in streptococci by LL + LYZ. The solubilization of the bulk of membrane lipids from staphylococci can also be achieved by Triton X-100 and by sodium lauryl sulfate and from group A streptococci by Triton X-100 plus LYZ. A variety of other detergents (e.g., Cetavlon, sodium taurocholate, cetyl pyrdinium chloride) have no lipid-releasing properties even in the presence of LYZ. The release of lipids by LYZ (in the presence of LL) from group A streptococci is related to its enzymatic activity, on a still unknown substrate, but not to its cationic nature as this muramidase cannot be replaced by a variety of cation substances (histone, polylysin, leukocyte cationic proteins, polymyxin B, and spermidine). The release of lipids from staphylococci by LL is not inhibited by a variety of anionic and cationic polyelectrocytes (heparin, liquoid, chondroitin sulfate, DNA histone, and polylysine) which markedly inhibit the release of lipids from group A streptococci by LL and LYZ. Streptococci that had been cultivated in the presence of subinhibitory concentrations of penicillin G lose their membrane phospholipids to a larger extent and by much smaller concentrations of LL and LYZ, as compared to controls, suggesting that the interference with the synthesis of the peptidoglycan increases the accessibility of the cell membrane to the lipid-releasing agents. The mechanism by which LL collaborates with LYZ in lipid release is still not known. The possible role of bacterial lipids and lyso compounds in the control of bacterial survival in inflammatory sites is briefly discussed. VL - 3 IS - 4 ER - TY - JOUR T1 -

Recreational therapy: do administrators exploit it?

JF - Nursing Homes Y1 - 1979 A1 - Isaac Ginsburg VL - 28 IS - 2 ER - TY - JOUR T1 -

The role of leukocyte extracts and myeloperoxidase in the lysis of staphylococci and the inhibition of bacteriolysis by anionic polyelectrolytes and by inflammatory exudates

JF - Advances in experimental medicine and biology Y1 - 1979 A1 - Isaac Ginsburg A1 - N. Ne'eman A1 - Meir Lahav A1 - Michael N. Sela VL - 121 ER - TY - JOUR T1 -

Effect of leukocyte hydrolases on bacteria. XV. Inhibition by antibiotics, metabolic inhibitors, and ultraviolet irradiation of the release by leukocyte extracts, trypsin, and lysozyme of lipopolysaccharide from gram-negative bacteria.

 

JF - Inflammation Y1 - 1979 A1 - D. Cohen A1 - J. Michel A1 - M. Ferne A1 - S. Bergner-Rabinowitz A1 - Isaac Ginsburg AB - Leukocyte extracts, trypsin, and lysozyme are all capable of releasing the bulk of the LPS from S. typhi, S. typhimurium, and E. coli. Bacteria which have been killed by heat, ultraviolet irradiation, or by a variety of metabolic inhibitors and antibiotics which affect protein, DNA, RNA, and cell wall synthesis no longer yield soluble LPS following treatment with the releasing agents. On the other hand, bacteria which are resistant to certain of the antibiotics yield nearly the full amount of soluble LPS following treatment, suggesting that certain heatlabile endogenous metabolic pathways collaborate with the releasing agents in the release of LPS from the bacteria. It is suggested that some of the beneficial effects of antibiotics on infections with gram-negative bacteria may be the prevention of massive release of endotoxin by leukocyte enzymes in inflammatory sites. VL - 3 IS - 4 ER - TY - JOUR T1 -

The role of lysosomal factors of leukocytes in the biodegradation and storage of microbial constituents in infectious granulomas

JF - Frontiers of Biology Y1 - 1979 A1 - Isaac Ginsburg VL - 48 ER - TY - JOUR T1 -

Effect of leukocyte hydrolases on bacteria. XIV. Bacteriolytic effects of human sera, synovial fluids, and purulent exudates on Staphylococcus aureus and Streptococcus faecalis: modulation by Cohn's fraction II and by polyelectrolytes.

JF - Inflammation Y1 - 1979 A1 - N. Ne'eman A1 - Michael N. Sela A1 - S. Chanes A1 - L. Bierkenfeld A1 - D. Kutani A1 - Meir Lahav A1 - Isaac Ginsburg AB - Normal sera and plasma, derived from humans, calves, rats, rabbits, horses, human synovial fluids, inflammatory exudates, and leukocyte extracts, when sufficiently diluted are highly bacteriolytic for Staph, aureus, Strep. faecalis, B. sutilis and to a variety of gram-negative rods. On the other hand, concentrated serum or the other body fluids are usually not bacteriolytic for these bacterial species. While the lysis of Staph, aureus and B. subtilis by diluted serum is not lysozyme dependent, lysis of Strep. faecalis is absolutely dependent on the concentration of lysozyme. The lytic factor in human serum is present in Cohn's fractions III, IV, and V. It is nondialyzable, resistant to heating for 75 degrees C and 20 min, and acts optimally at pH 5.0. Like leukocyte extracts, synovial fluids, and inflammatory exudates, it lyses only young staphylococci. The inability of concentrated serum to lyse Staph. aureus and Strep. faecalis is due to the presence in the gamma globulin fraction of a potent inhibitor, which can be partly removed by dilution of by adsorption upon the homologous bacteria. Lysis of the bacteria is also strongly inhibited by Cohn's fraction II (gamma globulin) by high-molecular-weight DNA, heparin, liquoid, and histone. The possible role played by serum globulin in the protection of bacteria against degradation by leukocyte is discussed. VL - 3 IS - 4 ER - TY - JOUR T1 -

Inflammatory lesions and bone resorption induced in the rat periodontium by lipoteichoic acid of Streptococcus mutans.

JF - Inflammation Y1 - 1979 A1 - ITAY A. BAB A1 - Michael N. Sela, A1 - Isaac Ginsburg A1 - THEODOR DISHON AB - Severe inflammatory lesions were induced in the periodontal tissues of the rat following the intragingival injection of lipoteichoic acid (LTA) from Streptococcus mutans. There was no difference in the severity and distribution of the lesions between nonimmunized rats and animals immunized against LTA after antigenic challenge. The lesions are characterized by the occurrence of granulation tissue, massive infiltration of PMNs, abscess formation, bone resorption, and new bone formation. Deacylated LTA and saline caused relatively mild inflammation, and no significant bone resorption or new bone formation was evident. The peak response was reached after 3 intragingival infections. The mechanisms by which LTA caused the pathological alterations in the rat periodontium and the possible relations of this experimental model to periodontal disease in the human are discussed. VL - 3 IS - 4 ER - TY - JOUR T1 -

The effect of leukocyte hydrolases on bacteria - XII

JF - Inflammation Y1 - 1978 A1 - M. Ferne A1 - Zvia Duchan A1 - Sonia Rabinowitz-Bergner A1 - Michael N. Sela A1 - Isaac Ginsburg AB - The effect of leukocyte hydrolases on bacteria - XII. The release of lipopolysaccharide (LPS) from Salmonella typhi by leukocyte extracts, lysozyme, inflammatory exudates and by serum and synovial fluid and the modulation by anionic and cationic polyelectrolytes of LPS release and the sensitization of erythrocytes VL - 3 IS - 1 ER - TY - JOUR T1 -

The effect of leukocyte hydrolases on bacteria. XI. Lysis by leukocyte extracts and by myeloperoxidase of a Staphylococcus aureus mutant which is deficient in teichoic acid, and the inhibition of bacteriolysis by lipoteichoic acid

JF - Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine Y1 - 1978 A1 - Michael N. Sela A1 - Itzhak Ofek A1 - Meir Lahav A1 - Isaac Ginsburg AB - A Staph, aureus mutant (52A5) which is deficient in wall teichoic acid (TA) was found to be highly susceptible to lysis by leukocyte extracts (ENZ) and by myeloperoxidase (MPO) when harvested from the stationary phase of growth, On the other hand, a staphylococcus mutant, which is deficient in N-acetyl glucosamine in its TA (52A2), the parent strain SH and a protein A rich strain Cowen I, could be lysed by the leukocyte factors only when harvested from the logarithmic phase of growth. VL - 159 IS - 1 ER - TY - Generic T1 -

The role played by leukocyte extracts and

inflammatory exudates in the release of

lipopolysaccharides from Gram negative

bacteria: relation to tissue damage

Induced during infections

T2 - Perspectives in Inflammation- Future Trends and Developments Y1 - 1977 A1 - Isaac Ginsburg A1 - Zvia Duchan A1 - S. Bergner-Rabinowitz A1 - M. Ferne AB - The role played by bacterial lipopolysaccharides (endotoxins) (LPS) in the initiation of tissue damage during bacterial infections, is well established. It is accepted that LPS is released from the invading bacteria following autolysis, and the interaction of the solubilized LPS with tissues and body fluids lead to the initiation of the physiological, pharmacological and pathological sequelae seen after infections with Gram negative bacterial. Previous studies from our laboratories have shown that the binding of LPS to membranes of RBC is markedly enhanced by heat-labile leukocyte factors2, and that leukocyte factors are also capable of activating ‘LPS’ for binding to cell surfaces. Since the ‘activation’ of LPS caused by this factor \s inhibited by protease inhibitors, it was postulated that proteases present Hn leukocytes and in inflammatory exudates may enhance tissue damage by increasing the passive sensitization of mammalian cells by LPS to subsequent lysis in the presence of antibodies and complement. JF - Perspectives in Inflammation- Future Trends and Developments CY - London ER - TY - CONF T1 -

FURTHER STUDIES ON THE BACTERICIDAL AND BACTERIOLYTIC EFFECTS OF HUMAN LEUKOCYTE EXTRACTS

T2 - MOVEMENT, METABOLISM AND BACTERICIDAL MECHANISMS OF PHAGOCYTES Y1 - 1977 A1 - Isaac Ginsburg A1 - N. Neeman A1 - C. Ephrati A1 - Michael N. Sela A1 - L. Bierkenfeld A1 - D. Kutani A1 - Meir Lahav AB - FURTHER STUDIES ON THE BACTERICIDAL AND BACTERIOLYTIC EFFECTS OF HUMAN LEUKOCYTE EXTRACTS: MODULATION BY ANTIBODIES CATIONIC PROTEINS, LYSOZYME, ANTIBIOTICS AND BY AUTOLYTIC SYSTEMS AND THE ROLE PLAYED BY SOME OF THESE FACTORS IN THE EXTRACTION OF LIPOTEICHOIC ACIDS FROM BACTERIA JF - MOVEMENT, METABOLISM AND BACTERICIDAL MECHANISMS OF PHAGOCYTES PB - Padua : Piccin Medical Books ER - TY - JOUR T1 -

The bacteriolytic effect of human dentoalveolar purulent exudates and leukocyte extracts

JF - Refuat Hapeh Vehashinayim Y1 - 1977 A1 - J. Ehrlich A1 - Michael N. Sela A1 - Meir Lahav A1 - Isaac Ginsburg VL - 26 IS - 4 ER - TY - JOUR T1 -

 

Effect of leukocyte hydrolases on bacteria - X. The role played by leukocyte factors, cationic polyelectrolytes, and by membrane-damaging agents in the lysis of Staphylococcus aureus: Relation to chronic inflammatory procesess

JF - Inflammation Y1 - 1977 A1 - Meir Lahav A1 - Isaac Ginsburg AB - A heat-stable factor present in extracts of human blood leukocytes is capable of lysing young Staphylococcusaureusat pH 5.0. Lysis is character- ized by breakdown of cell-wall components as judged by electron microscopic and biochemical analysis. The leukocyte extracts can be replaced by a variety of agents known to injure cell membranes, e.g., leukocyte cationic protein histone, polymyxin B, colimycin, phospholipase A, and lysolecithin. The mechanisms by which all these agents bring about the degradation of the sta- phylococcal walls was studied. By using ~4C-labeled cell walls devoid of cytoplasmic structures, it was demonstrated that none of the above-men- tioned agents had a direct lytic effect on purified cell walls. On the other hand, when any of these agents first interacted with intact staphylococci, a factor (presumably an autolysin) was generated that directly lysed the cell walls. Lysis of cell wails in the presence of intact staphylococci used as a source of autolysin was strongly inhibited by a variety of anionic poly- electrolytes such as heparine and liquoid. The possible role olayed by bacterial autolysins in the generation of microbial cell-wall comp~,nents capable of triggering chronic inflammation is discussed. VL - 2 IS - 2 ER - TY - JOUR T1 -

The Hebrew University's triad of goals

JF - The Alpha Omegan Y1 - 1977 A1 - Isaac Ginsburg VL - 70 IS - 2 ER - TY - JOUR T1 -

Effect of leukocyte hydrolases on bacteria. IX. The release of lipoteichoic acid from group A streptococci and from Strep. mutans by leukocyte extracts and by lysozyme: relation to tissue damage in inflammatory sites

JF - Inflammation Y1 - 1977 A1 - Michael N. Sela A1 - Meir Lahav A1 - Isaac Ginsburg AB - Human leukocyte extracts, egg white lysozyme, cationic proteins, polymyxin, colimycin, and phenol are capable of releasing lipoteichoic acids (LTA) from group A streptococci and Strep. mutans. While the extraction of LTA by phenol is optimal at pH 4.7, the release of LTA from streptococci by the other agents is optimal at pH 7.4. LTA released by all agents was found to have the same sensitizing abilities, as determined by passive hemagglutination, and to have a similar chemical composition, as shown by thin-layer chromatography and radioactive scanning. The LTA-releasing capacity of all the agents is strongly inhibited by normal human serum. The possible role played by LTA released by leukocyte factors in the pathogenesis of tissue damage during bacterial infections is discussed. VL - 2 IS - 2 ER - TY - JOUR T1 -

Experimental Models of Streptococcal Arthritis: Pathogenetic Role of Streptococcal Products and Prostaglandins and Their Modification by Anti-Inflammatory Agents

JF - Experimental Models of Chronic Inflammatory Diseases Y1 - 1977 A1 - Isaac Ginsburg A1 - U. Zor A1 - Y. Floman AB - Although a mass of evidence exists which supports the etiologic relationship between group A streptococcal infections and the pathogenesis of human disease (6, 36, 49, 103, 112), our knowledge of the mechanisms involved in the initiation of the tissue lesions characteristic of the sequelae of streptococcal infection in man is far from complete. The hallmarks of the poststreptococcal sequelae in humans are the development of rheumatic fever, arthritis, glomerulonephritis, chorea and other less defined clinical manifestations. Lasegue’s dictum (68) that “acute rheumatism licks the joints but bites the heart” still characterizes the significance of cardiac and joint involvement as “major” manifestations, which are related to their importance as diagnostic criteria, but do not necessarily refer to their importance in the severity of the process, its activity, or prognosis. VL - 6 ER - TY - JOUR T1 -

Can chronic and self-perpetuating arthritis in the human be caused by arthrotropic undegraded microbial cell wall constituants? A working hypothesis.

JF - Rheumatology and Rehabilitation Y1 - 1977 A1 - Isaac Ginsburg AB - Although the aetiological agents responsible for the initiation of rheumatoid arthritis in the human are not known, the possibility that the disease is of bacterial origin has been considered. The bacterial factors involved may be small fragments of undegraded wall components which persist for long periods within macrophages and trigger the active release of lysosomal enzymes which cause tissue destruction. The failure to identify such wall components in diseases tissues may be due to the lack of adequate sensitive techniques to detect minute amounts of these wall components, shown to trigger chronic destructive arthritis in laboratory animals. Two models of arthritis caused by mycobacterial and streptococcal wall components are described and the possible role played by immune responses, to the persisting bacterial factors, in the pathogenesis of human arthritis is discussed. VL - 16 IS - 3 ER - TY - CHAP T1 -

Degradation and survival of bacteria in sites of allergic inflammation

T2 - Infection and immunology in the rheumatic diseases Y1 - 1976 A1 - Isaac Ginsburg A1 - N. Neeman A1 - R. Gallily A1 - Meir Lahav JF - Infection and immunology in the rheumatic diseases PB - Oxford : Blackwell Scientific CY - Philadelphia ER - TY - JOUR T1 -

The effect of leukocyte hydrolases on bacteria - VII. Bactericidal and bacteriolytic reactions mediated by leukocyte and tissue extracts and their modifications by polyelectrolytes

JF - Inflammation Y1 - 1976 A1 - N. Ne'eman A1 - Zvia Duchan A1 - Meir Lahav A1 - Michael N. Sela A1 - Isaac Ginsburg AB - Crude extracts of human blood leukocytes were employed as a source of bactericidal and bacteriolytic agents againstStaphylococcus aureus. While the bactericidal action of the extracts was a very rapid process, bacteriolysis is a very slow process. Both the killing and the lysis of staphylococci depended on the age of the culture, maximal effects being obtained only with young cells. The killing of staphylococci by the extracts was absolutely dependent on the density of bacteria employed. On the other hand, bacteriolysis was only very slightly affected when large numbers of bacteria were employed. Both the bactericidal and bacteriolytic reactions were optimal at pH 5.0. Under similar conditions, extracts of pus and the "cocktail" of enzymes were both bactericidal and bacteriolytic, but extracts of small intestine and of platelets were not significantly bactericidal. Experiments, designed to differentiate between the bactericidal and bacteriolytic properties of the extracts showed that both properties were preserved following heating in acid solutions but were completely destroyed following heating in alkaline solutions. The bactericidal factor in the lysates could be readily adsorbed on large numbers of viableStaph. aureus andE. coli, but the bacteriolytic properties of the extracts could not be removed by adsorption. The bactericidal effect of the extracts could not be inhibited by a variety of anionic polyelectrolytes, but all these agents strongly inhibited the bacteriolytic effect. Moreover, several of the anionic substances potentiated the bactericidal effects mediated by the extracts. Potentiation of these effects was also caused by protamine sulfate and by polylysine, which were highly bactericidal by themselves. The only substance that was found to abolish the bactericidal effects of the extracts is ultracorten H. Historie and polylysine (which are highly bactericidal) lost their effects when mixed with certain concentrations of heparin or polyglutamic acid, which by themselves are not bactericidal, indicating that an appropriate balance between cationic and anionic substances may determine the bactericidal effects of cationic substances. Since the bactericidal properties of the lysates could not be abolished by any of the anionic macromolecular substances employed; it is suggested that the bactericidal agents present in crude whole lysates of leukocytes comprise a complex mixture of agents, some of which are not identical with cationic substances. Thus, the data suggest that the employment of highly purified cationic proteins of leukocytes and tissues to study bactericidal models may not reflect the actual conditions that prevail in inflammatory exudates. The possible role played by cationic and anionic polyelectrolytes in the control of bacterial survival and lysis in inflammatory exudates is discussed. VL - 1 IS - 3 ER - TY - JOUR T1 -

The effect of leukocyte hydrolases on bacteria VIII. The combined effect of leukocyte extracts, lysozyme, enzyme "cocktails," and penicillin on the lysis ofStaphylococcus aureus and group a streptococci in vitro

JF - Inflammation Y1 - 1976 A1 - C. Efrati A1 - T. Sacks A1 - N. Ne'eman A1 - Meir Lahav A1 - Isaac Ginsburg AB - Cultures ofStaphylococcus aureus, which are harvested from the stationary phase of growth, are extremely resistant to lysis by extracts of human blood leukocytes. Such bacteria are, however, rendered susceptible to bacteriolysis when cultivated in the presence of subinhibitory concentrations of penicillin G, nafcillin, or cloxacillin (0.05μg/ml). The lytic effect of the leukocyte extracts on the penicillin-grown bacteria is further augmented by the addition of egg-white lysozyme. Staphylococci, which are harvested from the logarithmic phase of growth in ordinary media, are susceptible to lysis by leukocyte extracts, maximal lysis being achieved with about 100μg/ml of leukocyte extracts. On the other hand, penicillin-grown staphylococci are lysed by much smaller amounts of leukocyte extracts (20μg/ml), and much shorter periods of incubation are needed to achieve maximal lysis. Similar results are obtained when the leukocyte extracts are substituted by a cocktail of lytic agents which contain crude trypsin, lysolecithin, and lysozyme. Lysis of the staphylococci by the leukocyte extracts, fortified by lysozyme, is optimal at pH 5.0 and is accompanied by the solubilization of the bulk of glucosamine, known to be mostly concentrated in the peptidoglycan of the cell wall. Penicillin-grown staphylococci are also more susceptible than controls to lysis by a mixture of histone and lysozyme. The lysis, by leukocyte extracts and by the cocktail of both regular and penicillin-grown staphylococci, is strongly inhibited to the same extent by heparin, liquoid, histone, protamine sulfate, IgG, and human serum. On the other hand, no inhibition of lysis is achieved by chloramphenicol, streptomycin, erythromycin, KCN, HgCl2, or by neutral polyelectrolytes. Group A streptococci, which are extremely resistant to degradation by leukocyte extracts or by the cocktail, when harvested from any phase of growth, also become susceptible to lysis by leukocyte extracts or by the cocktail when grown in the presence of small amounts of penicillin (0.004-0.008μ/ml). Bacteriolysis became even more pronounced when the reaction mixtures were incubated at 41 °C, a temperature likely to develop in patients with streptococcal infections. Electron-microscope examination of the staphylococci following treatment with leukocyte enzymes and penicillin revealed that both cell wall and cytoplasmic structures were severely damaged by the lytic agents. The mechanisms by which penicillin exposes the bacterial cell walls to cleavage by leukocyte extracts is discussed, and the phenomenon of enhanced susceptibility to lysis by leukocyte enzymes is related to the role played by undegraded bacterial constituents in the initiation of chronic inflammatory lesions. VL - 1 IS - 4 ER - TY - JOUR T1 -

The effect of leukocyte hydrolases on bacteria : VI. The role played by leukocyte extracts in the sensitization of RBC by lipopolysaccharides and by the cell-sensitizing factor of group A streptococci

JF - Inflammation Y1 - 1976 A1 - Mina Ferne A1 - S. Bergner-Rabinowitz A1 - Isaac Ginsburg AB - The effect of proteases and of extracts of human blood leukocytes and platelets on the sensitization of human red blood cells (RBC) by lipopolysaccharides (LPS) and by the cell-sensitizing factor (SF) of group A streptococci, as determined by passive hemagglutination, was studied. While treatment of RBC by trypsin, papain (10-1500Μg/ml), and plasmin markedly increased the binding of SF to RBC as determined by the passive hemagglutination test, small amounts of leukocyte and platelet extracts (25Μg protein) failed to enhance the sensitization of RBC. On the other hand, high concentrations of leukocyte extracts (>250Μg protein) destroyed, to a large extent, the capacity of SF to sensitize RBC. The inhibitory effect of the leukocyte extracts on the SF system was optimal at neutral pH and was inhibited by heat treatment, by phenylmethyl sulfonyl fluoride (PMSF), and by liquoid, indicating the participation of neutral proteases in this reaction. Treatment of LPS with small amounts of leukocyte extracts activated the LPS molecule; this treatment could replace the alkaline treatment needed to enhance the capacity of LPS to sensitize RBC. Very high hemagglutination titers were, however, obtained when both LPS and RBC were simultaneously treated with leukocyte extracts (25Μg protein). On the other hand, larger amounts of extracts destroyed receptors for LPS on RBC. Both the enhancing and destroying capacities of the leukocyte enzyme on the LPS system were abolished by PMSF. The simultaneous sensitization of RBC by SF and LPS showed that SF is a more dominant sensitizing agent. Histone blocked receptors in RBC for both SF and LPS. The effect of the histone was abolished by trypsin. Histone also strongly bound LPS and SF and abolished to a large extent their cell-sensitizing properties. The possible role played by leukocyte extracts in the initiation of tissue damage induced by cell-sensitizing products of bacteria is discussed. VL - 1 IS - 3 ER - TY - JOUR T1 -

The interaction of leukocytes and their hydrolases with bacteria in vitro and in vivo: the modification of the bactericidal and bacteriolytic reactions by cationic and anionic macromolecular substances and by anti-inflammatory agents

JF - Agents and Actions (Inflammation Research Y1 - 1976 A1 - Isaac Ginsburg A1 - Meir Lahav A1 - N. Ne'eman A1 - Z Duchan A1 - S. Chanes A1 - MN Sela AB - Acid hydrolases from extracts of human blood leucocytes lyse Staph.aureus, Staph.albus and Strep.faecalis in vitro. The leucocyte enzymes can be substituted by a lytic mixture which contains crude trypsin, lysolecithin, phospholipase C and lysozyme, which lyse other bacterial species, e.g. E.coli and Listeria which are resistant to leucocyte enzymes. Bacteriolysis by the lytic agents is strongly inhibited by the anionic polyelectrolytes, heparin, chondroitin sulphate, DNA, dextran sulphate and other sulphated mucopolysaccharides, by the cationic materials, histone, protamine sulphate, leucocyte cationic proteins and polylysine. Other strong inhibitors are trypsan blue and congo red, the phospholipids phosphatidyl serine and ethanolamine, gold thiomalate, extracts of coffee and tea and the anti-inflammatory agents, ultracorten-H, and ultracortenol. Bacteriolysis is also strongly inhibited by normal human serum and by synovial fluids from patients with a variety of joint diseases. The inhibitors in these body fluids are associated with the globulin fractions. Since mixtures of anionic and cationic polyelectrolytes, at equimolar concentrations, failed to inhibit bacteriolysis by leucocyte enzymes, it is postulated that a delicate balance between positively and negatively charged inhibitors control the degradation of cell wall components of bacteria in inflamed areas. Such bacterial components, induce 'storage type' granulomas. The possible role played by polyelectrolytes in the control of the inflammatory process induced by leucocyte hydrolases will be discussed. VL - 6 IS - 1-3 ER - TY - JOUR T1 -

The Role of Leukocytes and their Hydrolases in the Persistence, Degradation, and Transport of Bacterial Constituents  in Tissues

JF - Critical Reviews in Microbiology Y1 - 1976 A1 - Isaac Ginsburg A1 - Michael N. Sela, A1 - A. M. Dannenberg AB - The Role of Leukocytes and their Hydrolases in the Persistence, Degradation, and Transport of Bacterial Constituents in Tissues: Relation to Chronic Inflammatory Processes in Staphylococcal, Streptococcal, and Mycobacterial Infections and in Chronic Periodontal Disease Read More: http://informahealthcare.com/doi/abs/10.3109/10408417609106944?journalCode=mby VL - 4 IS - 3 ER - TY - CONF T1 -

Granulomata in Streptococcal Inflammation

Mechanisms of Localization Transport and

Degradation of Streptococci in Inflammatory Sites

T2 - Mononucler Phagocytes in Immunity, Infection and Pathology Y1 - 1975 A1 - Isaac Ginsburg A1 - S. Mitrani A1 - N. Neeman A1 - Meir Lahav JF - Mononucler Phagocytes in Immunity, Infection and Pathology PB - Blackwell Scientific Pubications OXFORD ER - TY - JOUR T1 -

 

The new streptozyme test for streptococcal antibodies. Studies in the value of this multiple antigen test in glomerulonephritis, acute pharyngitis, and acute rheumatic fever

JF - Clinical Pediatrics Y1 - 1975 A1 - S. Bergner-Rabinowitz A1 - S. Fleiderman A1 - Mina Ferne A1 - K. Rabinowitz A1 - Isaac Ginsburg AB - THE DETERMINATION of antistrep- tolysin 0 (ASO) in patients’ sera is most commonly performed as an aid in the diag- nosis of streptococcal infection and their sequelae.’ However, because of the differences in immune responses to a variety of streptococcal exoproducts in rheumatic fever and glomerulonephritis, it is advantageous to measure the level of more than one antis trep tococcal antibody, particularly in patients with low or borderline ASO levels. 2.3 The recently developed streptozyme test (A-STZ)l is a two-minute slide hemagglutina- tion procedure which quantitatively meas- ures multiple antibodies to streptococcal exracellular products. The reagents are sheep red blood cells sensitized simultaneously with streptolysin 0 (SLO), deoxyribonuclease B (DNase B), hyaluronidase (H), streptokinase (SK), and nicotinamide adenine dinucleotide glycohydrolase (NADG). A good correlation betweenA-STZandASOinseraofrheumatic fever patients has been demonstrated. In a comparative study’ of the STZ test with titers obtained with three of the antibody tests, ASO, ADNase B, and AH, the useful- ness of the streptozyme test for laboratories which perform only the ASO test has been demonstrated. Similar conclusions were drawn in a comparative study in our laboratory. his report deals with three main topics: 1) the streptozyme studies done in our laboratories on four of human categories sera: control group, acute pyodermal ne- tients and acute rheumatic fever patients; 2) the reproducibility and specificity of the streptozyme test; and 3) the development of ASTZ in rabbits immunized with nonviable and viable streptococci. VL - 14 IS - 9 ER - TY - JOUR T1 -

The effect of leukocyte hydrolases on bacteria : IV. The role played by artificial enzyme "cocktails" and tissue enzymes in bacteriolysis

JF - Inflammation Y1 - 1975 A1 - Isaac Ginsburg A1 - N. Ne'eman A1 - Zvia Duchan A1 - Michael N. Sela A1 - J. James A1 - Meir Lahav AB - Acid hydrolases of human blood leukocytes are highly lytic toStaph. albus, Staph. aureus, andStrep. faecalis. On the other hand, group A and viridans streptococci, encapsulated staphylococci, a variety of Gramnegative rods, andMyc. smegmatis are highly resistant to lysis by leukocyte extracts. The lytic effect of the leukocyte extracts can be mimicked by an artificial "cocktail" which contains crude trypsin, lysolecithin, phospholipase C, and lysozyme. This enzyme mixture is lytic to certain Gram-negative bacteria and encapsulated staphylococci which are resistant to lysis by leukocyte enzymes. Both the leukocyte lysates and the artificial cocktail are more lytic to bacteria harvested from the logarithmic phase of growth than to older cells.Staph. albus andStrep. faecalis, which are not lysed to any appreciable extent by extracts of rabbit intestines, lymphocytes, and platelets, undergo extensive lysis upon the addition of lysozyme, indicating that these cells contain preparatory prolytic agents which are activated by lysozyme. On the other hand, the lysis ofStaph. aureus by extracts of all these cells is less dependent upon lysozyme, indicating that other non-lysozyme-dependent lytic factors are involved in the lysis of this microorganism by certain tissue extracts. It is suggested that the resistance to lysis by leukocyte enzymes of bacterial cell-wall constituents may contribute to the pathogenesis of chronic sequellae, and that artificial enzyme cocktails be used for in vivo treatment of certain chronic inflammatory processes induced by bacteria. VL - 1 IS - 1 ER - TY - JOUR T1 -

The effect of leukocyte hydrolases on bacteria : V. Modification of bacteriolysis by antiinflammatory agents and by cationic and anionic polyelectrolytes

JF - Inflammation Y1 - 1975 A1 - Michael N. Sela A1 - Meir Lahav A1 - N. Ne'eman A1 - Zvia Duchan A1 - Isaac Ginsburg AB - Lysis of(14)C-labeledStaph. aureus by human blood leukocyte lysates, by extracts of rabbit small intestines and pancreas, and by the "cocktail" of enzymes (containing trypsin, lysolecithin, and lysozyme) is strongly inhibited by anionic polyelectrolytes (e.g., heparin, chondroitin sulfate, liquoid (polyanethole sulfonic acid), and DNA). Most of the lytic agents employed were inhibited by cationic polyelectrolytes (e.g., histone, protamin sulfate and polylysin), as well as by gold thiomalate, normal human serum, synovial fluids obtained from patients with knee-joint trauma, extracts of coffee, tea, and cocoa, Ultracorten- and Dexamethasone. On the other hand, some antiinflammatory agents tested (e.g., indomethacin, aspirin, hydrocortisone acetate and succinate, and prednisolone acetate and tributyl acetate) were not inhibitory. All the cationic polyelectrolytes employed and liquoid were also strong inhibitors of lysozyme. Since mixtures of cationic and anionic polyelectrolytes at equimolar concentrations failed to inhibit bacteriolysis, it is postulated that the balance between charged macromolecular substances, which are likely to accumulate in inflammatory foci, may determine the fate of cellular components of bacteria in inflamed tissues. The possible role played by lysosomal enzymes and by tissue inhibitors in tissue damage and in the survival of bacteria in chronic inflammatory lesions is discussed. VL - 1 IS - 1 ER - TY - JOUR T1 -

The effect of leukocyte hydrolases on bacteria. III. Bacteriolysis induced by extracts of different leukocyte populations and the inhibition of lysis by macromolecular substances

JF - The Journal of Infectious Diseases Y1 - 1975 A1 - Meir Lahav A1 - N. Ne'eman A1 - J. James A1 - Isaac Ginsburg AB - The lysis of 14C-labeled bacteria by hydrolases of human and rabbit leukocytes was studied in vitro. While Staphylococcus albus, Streptococcus faecalis, and Streptococcus mutans were highly susceptible to lysis, Staphylococcus auresus was intermediate in its susecptibility to lysis by the leukocyte enzymes. Group A Streptococcus, Listeria monocytogenes, Shigella flexneri, Escherichia coli, and Mycobacterium smegmatis were very resistant to degradation by these enzymes. The lytic activity of leukocyte lysates from human and rabbit blood was probably due to acid hydrolases of polymorphonuclear leukocytes. Extracts of human blood monocytes and of rabbit peritoneal and lung macrophages were less lytic for the bacteria tested. Lymphocytes and platelet extracts were not bacteriolytic. The lytic effect of the leukocyte lysates was not inhibited by KCN or sodium azide, but was abolished to a large extent by cationic polyelectrolytes such as protamine sulfate, histone and leukocyte cationic proteins, and poly-lysine, as well as by the anionic polyelectrolytes such as heparin, chondroitin sulfate, DNA, carrageenin, alginate sulfate, dextran sulfate, and ploy-L-glutamic acid. Other potent inhibitors of bacteriolysis were trypan blue, congo red, phosphatidic acid, normal immunoglobulins, and components of streptococcal cell wall. VL - 131 IS - 2 ER - TY - JOUR T1 -

Effect of Body Fluids and Macromolecular Substances on the Lysis of Group A Streptococci by Muramidases of Streptomyces albus

JF - INFECTION AND IMMUNITY (IAI) Y1 - 1975 A1 - Isaac Ginsburg AB - The lysis of group A streptococci by muramidases of Streptomyces albus is strongly inhibited by human, rabbit, and calf serum as well as by human synovial fluids and pus. Rabbit antisera to heat-killed streptococci were no more inhibitory to the lysis of the streptococci by the lytic enzyme than normal rabbit serum. The results indicate that muramidases of S. albus will not be useful for the in vivo treatment of chronic granulomatous lesions which had been induced by insoluble cell wall components of streptococci. VL - 11 IS - 4 ER - TY - Generic T1 -

The inhibition by basic and acidic polyelectrolytes of the degradation of bacteria by leukocyte enzymes

T2 - Activation Of Macrophages Y1 - 1974 A1 - Isaac Ginsburg A1 - Meir Lahav A1 - N. Neeman A1 - J. James JF - Activation Of Macrophages CY - Germany ER - TY - JOUR T1 -

The Effect of Leukocyte Hydrolases on Bacteria II. The Synergistic Action of Lysozyme and Extracts of PMN, Macrophages, Lymphocytes, and Platelets in Bacteriolysis

JF - Experimental Biology and Medicine Y1 - 1974 A1 - N. Ne'eman A1 - Meir Lahav A1 - Isaac Ginsburg AB - Extracts containing acid hydrolases and lysozyme derived from human and rabbit blood leukocytes, from rabbit peritoneal and lung macrophages and from peritoneal PMN are highly lytic for relabeled Staphylococcus albus, Streptococcus faecalis, and Streptococcus mutans. On the other hand, extracts of human and rabbit platelets and of rabbit lymphocytes, thymocytes, synovia and muscle are not lytic for these bacteria. A phenomenon is described in which lysozyme which is not lytic to these bacteria collaborates with nonlytic extracts of lymphocytes platelets, thymocytes, synovia and muscle in the lysis of Gram positive bacteria. Lysozyme also enhances the lysis of bacteria by extracts of PMN and macrophages. It is postulated that the bacteriolytic system present in PMN and macrophages comprises a group of preparatory nonlytic enzymes, also present in lymphocytes, thymocytes, platelets, and other tissues that prepare the peptidoglycan to cleavage by lysozyme. The preparatory enzyme systems of leukocytes and tissues have a pH optimum of 5.0 and are strongly inhibited by heparin and chondroitin sulfate. The relationship of the synergism between lysozyme and tissue enzymes in the degradation of microbial cells is discussed in relation to the pathogenesis of granulomatous inflammation. VL - 146 IS - 4 ER - TY - JOUR T1 -

Effect of leukocyte hydrolases on bacteria. I. Degradation of 14C-labeled Streptococcus and Staphylococcus by leukocyte lysates in vitro

JF - The Journal of Infectious Diseases Y1 - 1974 A1 - Meir Lahav A1 - N. Ne'eman A1 - E. Adler A1 - Isaac Ginsburg VL - 129 IS - 5 ER - TY - JOUR T1 -

Degradation of 14 C-labeled group A streptococci and micrococci in muscular lesions in the mouse

JF - Israel Journal of Medical Sciences Y1 - 1973 A1 - E. Adler A1 - H. Heller A1 - E. Weiner A1 - A. Masover A1 - S. Friedman A1 - Meir Lahav A1 - N. Ne'eman A1 - Isaac Ginsburg AB - In previous reports (1, 2) it has been shown that lysosomal enzymes derived from various populations of mammalian leukocytes failed to degrade 14C-Iabeled group A streptococci in vitro, On the other hand, Staphylococcus albus, Micrococcus Iysodeikticus and Escherichia coli were degraded to a large extent by leukocyte lysosomal enzymes. It was thus of interest to study the degradation of a variety of labeled microorganisms in vivo in inflammatory lesions in the thigh muscle of the mouse induced by the injection of heat-killed microorganisms. The results indicate that there may be a correlation between the degree of degradation of microorganisms by leukocyte lysates in vitro (1, 2) and the length of their persistence in lesion sites in vivo. VL - 9 IS - 4 ER - TY - JOUR T1 -

Effect of cationic and anionic polyelectrolytes and antibodies on the lysis of micrococci and streptococci by leukocyte lysates and lysozyme

JF - Israel Journal of Medical Sciences Y1 - 1973 A1 - Isaac Ginsburg A1 - N. Ne'eman A1 - Meir Lahav AB - In previous reports (1-3), it has been shown that lysosomal enzymes derived from a variety of mammalian leukocyte populations degrade 14C-Iabeled Micrococcus lysodeikticus and Staphylococcus albus extensively. On the other hand, group A streptococci are very resistant to lysis by leukocyte lysates. It has also been shown that, unlike S. albus and M. lysodeikticus, streptococci which are resistant to lysis in vitro persist for long periods in granulomatous lesions in mouse and rabbit tissues (1, 2). Other reports (4, 5) have shown that bacteria coated with specific antibodies are degraded at a slower rate following phagocytosis, as compared with untreated bacteria. Cationic polyelectrolytes, such as polylysine and polyarginine, agglutinate a variety of bacteria (6), and cationic proteins derived from leukocytes as well as from calf thymus histone are bactericidal for a variety of microorganisms (7). The possibility was therefore investigated that, by analogy to antibodies, cationic proteins may coat bacterial cells and thus interfere with their degradation by leukocyte lysosomal enzymes. VL - 9 IS - 5 ER - TY - JOUR T1 -

Alpha globulin decreases resistance of mice to infection with group A Streptococcus

JF - The Journal of Infectious Diseases Y1 - 1973 A1 - Moshe Glaser A1 - David Nelken A1 - Itzhak Ofek A1 - Sonia Bergner-Rabinowitz A1 - Isaac Ginsburg VL - 27 IS - 3 ER - TY - JOUR T1 -

Chronic self-perpetuating arthritis induced in rabbits by a cell-free extract of group A streptococci

JF - Experimental Biology and Medicine Y1 - 1973 A1 - H. Stein A1 - R. Yarom A1 - S. Levin A1 - T. Dishon A1 - Isaac Ginsburg A1 - T. N. Harris AB - Self-perpetuating arthritis was induced in knee joints of rabbits by intraarticular injections of large amounts of cell free extract derived from group A streptococci disintegrated mechanically. The pathological alterations were characterized by synovial lining cell proliferation, polymorphonuclear and mononuclear cell infiltration with the appearance of pseudo-follicles and pannus formation. Electron microscopical proliferation of B cells was predominant. An active inflammatory exudate and numerous new capillaries were also seen. The induced arthritis was self-perpetuating and appears to resemble human rheumatoid arthritis. VL - 143 IS - 4 ER - TY - JOUR T1 -

Evaluation of streptozyme and antistreptolysin O tests in streptococcal pyodermal nephritis

JF - Applied Microbiology Y1 - 1973 A1 - S. Bergner-Rabinowitz A1 - I. Ofek A1 - S. Fleiderman A1 - M. Zohar A1 - K. Rabinowitz A1 - Isaac Ginsburg AB - The evaluation of the streptozyme test in sera from 34 patients with streptococcal pyodermal nephritis was studied. Ninety-seven percent of the patients developed high titers of antistreptozyme antibodies on the first bleeding after hospitalization, in contrast to only 40% of patients who developed elevated antistreptolysin O titers. The high antistreptozyme titers declined during convalescence and reached normal levels in the sixth month after onset of the disease. The most significant fall in titers occurred between 1 and 2 months from the onset of disease. The streptozyme test may be particularly helpful as a rapid screening test for antibodies in streptococcal pyodermal nephritis. VL - 26 IS - 1 ER - TY - Generic T1 -

The localization, translocation, persistence

and degradation of Group A streptococci in tissues:

relation to poststreptococcal sequelae

T2 - Streptococcal Disease and the Community Y1 - 1972 A1 - Isaac Ginsburg AB - Although numerous epidemiological and clinical studies have shown a definite relationship between a previous infection with strains of Group A streptococci and the appearance of sequelae (rheumatic fever, arthritis, nephritis), the mechanisms which lead to their development are still not fully understood. Since man is the only animal species which suffers from natural infections with Group A streptococci, and since it is agreed that viable streptococci cannot usually be isolated from the lesions characteristic of the chronic complications, Koch’s postulate can at best incriminate these micro-organisms only in the etiology of the acute infections but not in their subsequent complications. Despite many attempts to duplicate rheumatic fever, arthritis and acute glomerulonephritis in laboratory animals including higher apes, as a rule, the tissue lesions which developed in some of the animals bore little resemblance to the human lesions, and no true duplication of a disease syndrome similar to that seen in human beings has been reported. Two major theories have been proposed by various investigators to explain the nature of poststreptococcal complications. One theory proposes that the toxic effects of some streptococcal products (streptolysins O and S, erythrogenic toxin, proteinase, cell-wall mucopeptide-polysaccharide complex) are responsible for the initiation of the chronic lesions in the heart, joint and kidney characteristic of poststreptococcal diseases. The second theory suggests that the immunopathological phenomena (immune complex disease, cross-reactive immunity, delayed hypersensitivity) which develop in certain pa- tients who have become sensitized to one or more of the streptococcal products are responsible for the initiation of the disease in man. These two hypotheses are not, of course, mutually exclusive. Although no unified theory has been advanced which adequately explains the nature of the various post- streptococcal complications, a combination of both views may fit many, if not all, the features characteristic of these sequelae. Some theories on the pathogenesis of human poststreptococcal diseases and on the mechanisms of tissue injury induced by Group A streptococci have been recently reviewed (Taranta and Uhr, 1971; Ginsburg, 19720, b). The purpose of this paper is to describe some of the mechanisms by which Group A streptococci localize and persist in mammalian tissues and to relate the experimental models to the pathogenesis of poststreptococcal sequelae in man. JF - Streptococcal Disease and the Community CY - Amsterdam ER - TY - JOUR T1 -

Red cell-sensitizing antigen of group A streptococci. I. Biological and chemical properties

JF - Israel Journal of Medical Sciences Y1 - 1972 A1 - N. Ne'eman A1 - Isaac Ginsburg AB - The cell-sensitizing factor (SF) of group A streptococci is a teichoic acid which can sensitize mammalian cells to agglutination and lysis in the presence of anti ·SF antibodies and complement. SF is highly immunogenic in the rabbit when bound naturally to some constituent of the streptococcus cell, but only feebly so when it is extracted from the cells by phenol. Both rabbit and human antibodies to SF, which are mainly associated with the macroglobulin fraction (IgM) of serum, are destroyed by treatment with 2-mercaptoethanol. While human anti-SF antibodies are readily destroyed by freezing and thawing and by heating to 58 C, the rabbit anti-SF antibodies are not destroyed at 64 C and are relatively resistant to repeated freezing and thawing. Complexes formed between SF and rabbit antibodies fix complement both in the absence and presence of red blood cells (RBC). Anti-SF antibodies interact with SF and prevent the latter from sensitizing RBC. Rabbits immunized with heat-killed streptococci and which developed anti-SF antibodies, developed severe arthritis when SF was injected into their knee joints. The arthritic lesions were characterized by a marked proliferation of the synovial membrane, a chronic inflammatory exudate and the accumulation of large numbers of lymphocytes in the form of "pseudolymphatic follicles." Nonimmunized animals failed to develop such lesions. It is suggested that sensitization of cells with SF during streptococcal infection may lead to passive immune cytolysis and may thus contribute to the pathogenicity of streptococci. VL - 8 IS - 11 ER - TY - JOUR T1 -

Dialyzable form of an extracellular streptococcal toxin causing histopathologic and biochemical changes in rabbits

JF - Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine Y1 - 1972 A1 - E. Gazit A1 - Isaac Ginsburg A1 - T. N. Harris AB - Earlier reports had described the presence, in supernates of streptococcal steady-state cultures, of a macromolecular toxin which causes infiltrative and necrotic lesions in the heart and liver of rabbits and changes in the serum level of certain enzymes and lipids. In the present study, following treatment of the culture supernate concentrates with trichloroacetic acid and ethanol, and dialysis, material with these biologic activities has been found, in the dialysate, and was not excluded by Sephadex G-15. The molecular weight of the toxin, by this criterion, is near that of vitamin B12. VL - 140 IS - 3 ER - TY - JOUR T1 -

Mechanisms of cell and tissue injury induced by group A streptococci: relation to poststreptococcal sequelae

JF - The Journal of Infectious Diseases Y1 - 1972 A1 - Isaac Ginsburg VL - 126 IS - 4 ER - TY - JOUR T1 -

Red cell-sensitizing antigen of group A streptococci. II. Immunological and immunopathological properties

JF - Israel Journal of Medical Sciences Y1 - 1972 A1 - N. Ne'eman A1 - Isaac Ginsburg VL - 8 IS - 11 ER - TY - JOUR T1 -

Mechanisms of Cell and Tissue Injury Induced by Group A Streptococci: Relation to Poststreptococcal Sequelae

JF - The Journal of Infectious Diseases Y1 - 1972 A1 - Isaac Ginsburg VL - 126 IS - 3 ER - TY - JOUR T1 -

Oxygen-Stable Hemolysins of Group A Streptococci VIII. Leukotoxic and Antiphagocytic Effects of Streptolysins S and O

JF - INFECTION AND IMMUNITY (IAI) Y1 - 1972 A1 - I. Ofek A1 - S. Bergner-Rabinowitz A1 - Isaac Ginsburg AB - Streptolysin S exists in a cell-bound form and as an extracellular complex between a nonspecific carrier (serum, serum albumin, ribonucleic acid [RNA], Triton, Tween) and a hemolytic moiety (probably a peptide) synthesized by streptococci. Although all the forms of streptolysin S, at 100 hemolytic units, killed mouse leukocyte monolayers, the time needed to kill 100% of the cells varied with the different streptolysin S preparations. Whereas 30 min was sufficient for the cell-bound hemolysin to kill all of the cells, 60 and 180 min were required when RNA streptolysin S and serum streptolysin S, respectively, were employed. Addition of 10% mouse serum to RNA streptolysin S or to cell-bound hemolysin delayed the killing of the leukocytes. The delayed killing observed with serum and albumin hemolysins is probably due to competition for the hemolytic moiety between the carrier molecules and target sites (phospholipids) upon the leukocyte membrane. Serum streptolysin S must be constantly incubated with the cells for 90 min for 100% of the cells to undergo cytopathic changes upon subsequent incubation for an additional 90 min. Streptolysin S inhibitor (trypan blue) added to the system after 30 or 60 min of incubation resulted in the killing of 50 and 100% of the leukocytes, respectively, when the cells were further incubated for 120 min. It is suggested that 30 min of incubation was not sufficient for the transfer of enough streptolysin S molecules upon the cell surface to allow killing of all of the cells. Sublethal amounts of streptolysin S, streptolysin O, and saponin suppressed phagocytosis of streptococci by mouse peritoneal macrophages. This effect was abolished by inhibitors of streptolysin S (trypan blue) and of streptolysin O and saponin (cholesterol). With sublethal amounts of streptolysin S, no inhibition of the reduction of nitro blue tetrazolium by nonphagocytosing cells was observed, but these amounts of streptolysin S caused a 50% inhibition of the reduction of nitro blue tetrazolium by phagocytosing leukocytes. It is suggested that some metabolic systems, which are normally enhanced during phagocytosis, have been affected by sublethal doses of streptolysin S. The results indicate that the in vivo production of small amounts of streptolysins S and O by group A streptococci may inhibit phagocytosis and may thus contribute to the invasiveness and pathogenicity of this microorganism. VL - 6 IS - 4 ER - TY - JOUR T1 -

Application of Enzyme Production Properties in Subtyping of Group A Streptococci According to T Type

JF - Applied Microbiology Y1 - 1971 A1 - I. Ofek A1 - S. Fleiderman A1 - S. Bergner-Rabinowitz A1 - Isaac Ginsburg AB - The production of extracellular nicotinamide adenine dinucleotide glycohydrolase (NADG) and the cell-bound lipoproteinase (serum opacity reaction, SOR) by strains of different serological types of group A streptococci, in relation to the T typing, was studied. The production of both NADG and SOR, or only one of them, was found to be characteristic of serotypes, as determined by M and T antigen. No difference in the production of these enzymes was found in relation to M-positive and M-negative variants. Investigation into NADG and SOR production as related to the T type enabled the division of a single agglutination pattern into four main groups, each of which corresponds to one specific M type or more. Of the 370 strains belonging to 12 different T-agglutination patterns, 21% produced both enzymes and 42.5% failed to produce any of them, whereas the remaining 36.5% produced only one out of the two enzymes. Five streptococcal types which did not produce NADG and SOR also failed to synthesize streptolysin S at the early logarithmic phase of growth, indicating that streptolysin S production by young cultures may be also related to serotype. No correlation was found between the production of NADG-SOR as related to serotype and the production of streptolysin O, acid phosphotase, esterase, N-acetylglucosaminidase, hyaluronidase, streptokinase, and the cell-sensitizing factor. The practical and potential usefulness of NADG and SOR production in epidemiological studies is discussed. VL - 22 IS - 5 ER - TY - JOUR T1 -

The focus of infection theory: A new look at the possible relation to poststreptococcal sequelae

JF - Human Pathology Y1 - 1971 A1 - Isaac Ginsburg VL - 2 IS - 3 ER - TY - JOUR T1 -

Phosphatase, Esterase, N-Acetylglucosaminidase, and Adenosine Triphosphatase of Group A Streptococci

JF - Experimental Biology and Medicine Y1 - 1971 A1 - Isaac Ginsburg A1 - M. Heller A1 - H.A. Gallis AB - Washed suspensions of group A, C, and G streptococci and group A L-forms possess phosphatase, esterase, and N-acetylglucosaminidase, respectively. Cell-free extracts, obtained from streptococci and Informs by mechanical disintegration or by treatment of group A streptococci with phage-associated lysin, possess, in addition to these enzymes, an adenosine triphosphatase (ATPase). Over 90% of the total ATPase and NAGAase and 50% of phosphatase and esterase activities were solubilized by cell breakage, indicating that the latter 2 enzymes are membrane-bound. A partial separation between the phosphatase, NAGAase, and ATPase was achieved by gel filtration of cell-free extracts on Sephadex G-200. Phosphatase was eluted with high molecular weight material excluded from the column. NAGAase and ATPase were associated with much lower molecular weight fractions, while esterase activity was present in both high and low molecular weight fractions. Studies on substrate specificity showed that fractions which split PNP-phosphate also split PNP-acetate and PNP-propionate fractions which split ATPase also split CTP, ITP, and GTP but to a lesser extent. Fractions which were active against β-napthylacetate also split β-naphthyl butyrate (15% efficiency); no activity against longer fatty acid esters of PNP or β-naphthyl derivatives was present. VL - 137 IS - 2 ER - TY - JOUR T1 -

Localization of Group a Streptococci and Particles of Titanium Dioxide in Arthritic Lesions in the Rabbit

JF - The Journal of Infectious Diseases Y1 - 1971 A1 - Isaac Ginsburg A1 - Rama Trost VL - 123 IS - 3 ER - TY - JOUR T1 -

Oxygen-Stable Hemolysins of Group A Streptococci VII. The Relation of the Leukotoxic Factor to Streptolysin S

JF - The Journal of Infectious Diseases Y1 - 1970 A1 - Isaac Ginsburg A1 - Itzhak Ofek A1 - Sonia Bergner-Rabinowitz VL - 122 IS - 6 ER - TY - JOUR T1 -

Group A streptococci: localization in rabbits and guinea pigs following tissue injury

JF - Science Y1 - 1969 A1 - Isaac Ginsburg A1 - H.A. Gallis A1 - R.M. Cole AB - Rabbits injected intravenously with extracellular products ("toxins") of group A streptococci develop myocardial, muscular, and hepatic lesions. When such animals are then challenged with fluorochrome-labeled group A streptococci or with titanium oxide particles the labeled bacteria or particles localize within phagocytic cells in the tissue lesions caused by the toxins. Similarly, labeled streptococci or titanium oxide particles will also localize within phagocytic cells in skin lesions of guinea pigs that develop delayed hypersensitivity to tuberculin or to bovine gamma globulin. It is proposed that a combined mechanism of injury and localization of bacteria in damaged tissues may be responsible for poststreptococcal sequelae or other chronic inflammatory diseases. VL - 166 IS - 3909 ER - TY - JOUR T1 -

Persistence of group A streptococci labeled with fluorescein isothiocyanate in inflammatory sites in the heart and muscle of mice and rabbits

JF - Experimental Biology and Medicine Y1 - 1969 A1 - N. Rickles A1 - Z. Zilberstein A1 - S. Kraus A1 - G. Arad A1 - M. Kaufstein A1 - Isaac Ginsburg AB - Studies on the host parasite relationship in experimental streptococcal infections have been greatly aided by fluorescent antibody techniques (1). By such methods it is possible to follow the localization and persistence of group A streptococcal antigen in cells and tissues of laboratory animals (2-6). To detect such antigens by fluorescent techniques, frozen sections are often employed and the antisera to streptococcal antigens must be repeatedly absorbed with organ powders to remove nonspecific staining. The present communication describes a simple method for applying a label of fluorescein isothiocyanate (FITC) to living group A streptococci, streptococcal cell-wall fragments,mucopeptides, and streptococcal Lforms. Such labeled streptococci and products were found to persist for long periods of time in inflammatory sites in the muscle and heart of mice and rabbits. VL - 131 IS - 2 ER - TY - JOUR T1 -

Immunological and biological nature of antigens of Streptococcus mitis and Streptococcus salivarius

JF - Israel Journal of Medical Sciences Y1 - 1968 A1 - Ruth Finkel A1 - Isaac Ginsburg AB - Extracellular antigens have been isolated from Streptococcus mitis, Streptococcus salivarius and group A streptococcal cultures grown in a synthetic medium. Analysis of the antigens was performed by immunoelectrophoretic and double diffusion techniques using rabbit immune sera. S. mitis cultures produced 10 antigens, S. salivarius six antigens and group A streptococcus 12 antigens, when tested with their corresponding antisera. S. mitis and S. salivarius antigens had only one common antigen when tested with antisera to both antigen pools. No cross reaction was found between the exo-antigens of group A and viridans streptococci. While the extracellular antigen pool of group A streptococci contained ribonuclease, deoxyribonuclease, hyaluronidase, diphosphopyridine-nucleotidase, streptokinase and streptolysin 0, that of S. mitis contained only ribonuclease and that of S. salivarius contained hyaluronidase and collagenase. Each of the three streptococcal antigen pools contained a hemosensitizing factor which sensitized mammalian cells to passive immune kill. Sonicates produced from the mitis, salivarius and group A streptococcus contained six antigens, most of which cross reacted with each other. S. mitis sonicates were separated into six fractions by ion exchange chromatography on ECTEOLA cellulose, and into three major fractions following gel-filtration on Sephadex 0-200 columns. Rabbits injected i.v. with sonicates derived from S. mitis developed cardiac and hepatic lesions which, in some cases, were accompanied by a steep rise in serum glutamic oxalacetic transaminase, sorbitol dehydrogenase and total lipids. The relationship of tissue damage to enzyme rise is discussed in relation to the possible early diagnosis of tissue damage following streptococcal infection. VL - 4 IS - 2 ER - TY - JOUR T1 -

Cardiac and muscular lesions in mice and rabbits injected with group A streptococcal products

JF - Pathologia et Microbiologia Y1 - 1968 A1 - Z. Bentwich A1 - Z. Silberstein A1 - J. H. Boss A1 - Isaac Ginsburg VL - 31 ER - TY - JOUR T1 -

Toxic effects induced in rabbits by extracellular products and sonicates of group A streptococci.

JF - Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine Y1 - 1968 A1 - G. Spira A1 - Z., Silberstein A1 - T. N. Harris A1 - Isaac Ginsburg AB - Rabbits injected with streptococcal extracellular protein (SEP) developed degenerative and infiltrative lesions in the heart and liver, with coagulation necrosis and multinucleated giant cells in the latter organ. The majority of these rabbits also showed elevated levels of glutamic-oxalacetic transaminase, or of sorbitol dehydrogenase, and all showed elevated serum lipids. These biochemical indications of cell injury could be found within 2 to 4 hours after a first injection of SEP. No such biochemical or pathologic effects were found following an injection of heated SEP or a commercially available streptokinase-streptodornase preparation from group C streptococcal culture. In a preliminary fractionation of SEP all the activity was found in a fraction not adsorbed to DEAE cellulose at pH 7.4 (0.05 M P04). The active fraction contained at least five antigens and four of the known streptococcal enzymes. Injection of extracts of sonically disrupted streptococci produced similar biochemical and pathologic changes. There was some cross-reacting material between the sonicates and anti-SEP serum. VL - 127 IS - 4 ER - TY - JOUR T1 -

Experimental arthritis in the rabbit induced by group a streptococcal products

JF - Experientia Y1 - 1968 A1 - Isaac Ginsburg A1 - Z. Silberstein A1 - G. Spira A1 - Z. Bentwich A1 - J. H. Boss AB - Intraartikuläre Injektion von Streptolysin-S-freien extrazellulären Produkten der Streptokokken Gruppe A verursacht eine zunächst akute, in der Folge aber subkutane Synovitis. Die Veränderungen gleichen denjenigen nach Injektion von Streptolollensonikaten, so dass angenommen wird, ausser Streptolysin S bedingen auch andere streptokokkale Faktoren eine Arthritis. VL - 24 IS - 3 ER - TY - JOUR T1 -

Separation of anticomplementary material and plasminogen from a cytotoxic factor active against Ehrlich ascites cells in Cohn fractions I-3 b fluorocarbon and n-butanol

JF - Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine Y1 - 1967 A1 - Isaac Ginsburg A1 - T. Dishon VL - 126 IS - 2 ER - TY - JOUR T1 -

Organ Lesions Produced in Rabbits by Group a Streptococci and Some of their Extracellular Products

JF - The American Journal of Pathology Y1 - 1967 A1 - N. Zeiri A1 - Z. Bentwich A1 - J. H. Boss A1 - Isaac Ginsburg A1 - T. N. Harris AB - Many studies have been made of tissue alterations due to infections with Group A streptococci in laboratory animals. Cardiac lesions characterized by muscle necrosis, myocarditis, and giant-cell formation have been reported in a variety of laboratory animals following injections of living Group A streptococci and some of their products.1l Some of these lesions were described as quite similar to the Aschoff bodies of rheumatic carditis.4 The mechanism of formation of these cardiac lesions has been attributed to toxic effects of streptococcal products,6 7 to immune response to streptococcal components (hypersensitivity or autoimmunity) ,10 or to combinations of these processes. Among these studies, the pharyngeal cavity of animals was used as the portal of entry of streptococci only in that of Glaser et al.,11 who found cardiac lesions within 72 hr. of a single intratonsillar injection of virulent Group A streptococci. These lesions were focal, and showed muscle necrosis, infiltrations of mononuclear cells, and occasional giant cells. No streptococci could be isolated from such lesions, and it was concluded that the lesions were probably not caused by an immunologic process."' The present report describes the induction of lesions in cardiac and other tissues of rabbits following injection, by intratonsillar and other routes, of streptococcal extracellular products (SEP) obtained from Group A streptococci grown in steady-state culture. These lesions occured soon after single injections of these materials and probably reflect direct toxic effect on the cells of these tissues. VL - 51 IS - 3 ER - TY - JOUR T1 -

Cell sensitizing products of streptococci

JF - Immunology Y1 - 1967 A1 - T. Dishon A1 - Ruth Finkel A1 - Z. Marcus A1 - Isaac Ginsburg AB - Various streptococcal species produce an haemosensitizing factor during the logarithmic phase of growth. A variety of mammalian cells sensitized with this factor become agglutinated following the addition of antistreptoccocal serum and also undergo cytopathic changes in the presence of complement. The haemosensitizing factor is thermostable and is unaltered by trypsin, papain, chymotrypsin, lipases or ribonucleases. Attempts to destroy the binding sites on the cell membrane by treatment with phospholipase C from Clostridium welchii or by neuraminidase failed. Treatment with trypsin or papain on the other hand markedly increased the binding capacity of red blood cell for the haemosensitizing factor. Studies on the nature of the binding sites on the erythrocyte membrane of the haemosensitizing factor suggest that cholesterol and phospholipids constitute some of the binding sites for this factor. VL - 13 IS - 3 ER - TY - Generic T1 -

LESIONS PRODUCED IN RABBITS FOLLOWING THE INTRACARDIAC INJECTION OF STREPTOCOCCAL CELL WALL COMPONENTS

 

T2 - CURRENT RESEARCH ON GROUP A STREPTOCOCCUS Y1 - 1966 A1 - Isaac Ginsburg A1 - N. Zeiri A1 - J. H. Boss JF - CURRENT RESEARCH ON GROUP A STREPTOCOCCUS CY - Paris ER - TY - JOUR T1 -

Binding of streptolysin S to red blood cell ghosts and ghost lipids

JF - Israel Journal of Medical Sciences Y1 - 1966 A1 - N. Elias A1 - M. Heller A1 - Isaac Ginsburg VL - 2 IS - 3 ER - TY - JOUR T1 -

Oxygen-stable hemolysins of group A streptococci. V. Effect on rat heart and kidney cells grown in tissue culture

JF - Experimental and Molecular Pathology Y1 - 1966 A1 - Z. Marcus A1 - AM. Davies A1 - Isaac Ginsburg AB - The effects of streptolysin S and cell-bound hemolytic factor were tested on tissue cultures of rat heart and kidney. Cytopathogenic changes were observed, characterized by swelling, cytoplasmic vacuolization and bleb formation and cells were disintegrated within 1–2 hours. These changes were abolished by known inhibitors of streptolysin S. VL - 5 IS - 2 ER - TY - JOUR T1 -

OXYGEN-STABLE HEMOLYSINS OF GROUP A STREPTOCOCCI 

III. THE RELATIONSHIP OF THE CELL-BOUND HEMOLYSIN TO STREPTOLYSIN S

JF - The Journal of Experimental Medicine Y1 - 1965 A1 - Isaac Ginsburg A1 - Z. Bentwich A1 - T. N. Harris AB - The relationship of the streptococcal hemolysin which is recognized on incubation of RBC with streptococcal cells (cell-bound hemolysin, CBH), to RNA hemolysin, a representative of oxygen-stable hemolysin (streptolysin S) has been studied. A number of similarities have been found in the conditions for optimal production of each of these hemolysins, a requirement for cysteine, Mg++, and glucose; maximal production by streptococci in the stationary phase; similar curves of pH-dependence. In both systems, the production of hemolysin was inhibited by certain antibiotics, by ultraviolet irradiation, and by sonic disruption and was absent in the same streptococcal mutant strain. The hemolytic activity of both systems was inhibited by lecithin, trypan blue, and papain. Similarities were also found in relative susceptibilities to the two hemolytic systems of erythrocytes of a number of animal species. These data support a suggestion advanced in an earlier study that a streptococcal hemolytic moiety, which can be induced by, and carried on, a number of diverse agents to comprise the group of oxygen-stable hemolysins, serves, in its original attachment to a component of the streptococcal cell, to produce the hemolytic effect recognized as the cell-bound hemolysin. VL - 121 IS - 4 ER - TY - JOUR T1 -

OXYGEN-STABLE HEMOLYSINS OF GROUP A STREPTOCOCCI 

JF - The Journal of Experimental Medicine Y1 - 1965 A1 - Isaac Ginsburg A1 - T. N. Harris AB - In studies of the mechanism of lysis of red blood cells by washed streptococci with hemolytic activity (cell-bound hemolysin, CBH) no components released spontaneously by RBC or streptococci, or by interaction between these cells, could be found to induce the formation of soluble hemolysin by the streptococci. It was also found that separation of RBC from streptococci even by Millipore filter or a very thin layer of agar could prevent their hemolysis. By means of cellulose columns it was possible to separate RBC from streptococci after a short incubation. RBC thus separated from streptococci with which they had been incubated underwent hemolysis on subsequent incubation at 37°C. By varying the period of incubation prior to separation it was possible to demonstrate the transfer of increasing amounts of hemolysin from streptococci to RBC with increasing periods of incubation. A considerable part of this appeared to be at a constant rate. A theory is presented on the relationship between the streptococcal cell-bound hemolysin and the group of oxygen-stable streptococcal hemolysins, in terms of a transferable hemolytic moiety and binding sites for this moiety on the streptococcal cell, on various molecular species which can act as inducers of the oxygen-stable hemolysins, and on the RBC, with the affinity of the respective binding sites for the hemolytic moiety increasing in that order. VL - 121 IS - 4 ER - TY - JOUR T1 -

EFFECT OF CYSTEINE ON FORMATION OF STREPTOLYSIN S BY GROUP A STREPTOCOCCI

JF - Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine Y1 - 1964 A1 - Isaac Ginsburg A1 - Z. Bentwich AB - Cysteine and other sulfhydryl compounds markedly enhance the formation of streptolysin S by 4 strains of group A streptococci. In the presence of cysteine (0.001 M) 10,000-30,000 hemolytic units per ml were obtained from strain S 84 type 3 in comparison with 1,000-3,000 units in the absence of cysteine. The role of cysteine in formation of hemolysin is not clear but it probably acts as a donor of SH compounds essential for an unknown process, rather than as a reducing agent. The inhibition of hemolysin formation by 3 amino acid analogues phenylserine, phenylglycine and acetyl-pro-line is reversed to a large extent by sulfhydryl compounds. Thus 0.002 M of cysteine reverses to a large extent the inhibition of hemolysin formation caused by as much as 0.1 M of phenylserine. VL - 117 ER - TY - JOUR T1 -

OXYGEN-STABLE HEMOLYSINS OF BETA-HEMOLYTIC STREPTOCOCCI.

JF - Ergebnisse der Mikrobiologie, Immunitätsforschung und experimentellen Therapie Y1 - 1964 A1 - Isaac Ginsburg A1 - T. N. Harris VL - 38 ER - TY - JOUR T1 -

The Effect of Cortisone and 6-Mercaptopurine on Lesions Induced by Intramyocardial Injection of Streptococci

JF - Pathologia et Microbiologia Y1 - 1963 A1 - A. Laufer A1 - Isaac Ginsburg A1 - I. GERY A1 - AM. Davies VL - 26 IS - 3 ER - TY - JOUR T1 -

MYOCARDITE GRANULOMATEUSE EXPERIMENTALE: UNE REACTION D'HYPERSENSIBILITE?

JF - Extrait de Pathaologie-Biologie Y1 - 1963 A1 - A. Laufer A1 - I. GINSBURG A1 - I. GERY VL - 11 IS - 11-12/13-14 ER - TY - JOUR T1 -

OXYGEN-STABLE HEMOLYSINS OF GROUP A STREPTOCOCCI

II. CHROMATOGRAPHIC AND ELECTROPHORETIC STUDIES

JF - The Journal of Experimental Medicine Y1 - 1963 A1 - Isaac Ginsburg A1 - T. N. Harris AB - The oxygen-stable streptococcal hemolysins, which can be induced by a number of diverse substances, have been studied. Differences among these hemolysins have been found in electrophoresis, chromatography, pH stability, and susceptibility to some organic solvents and to an enzyme, RNAase. These properties have in each case been found to characterize the inducing substances as well. In a number of instances it has been found possible to incubate one inducer with the hemolysin induced by another of these agents and then, after appropriate fractionation, to find hemolytic activity in the fraction containing the fresh inducer. These observations suggest that the oxygen-stable streptococcal hemolysins are constituted as carrier-hemolysin complexes, the carriers being the set of molecular species effective as inducers, and the prosthetic group being transferred from one carrier to another under appropriate conditions. After transfer of the hemolytic moiety from a hemolysin molecule which is susceptible to inactivation by a given agent or set of conditions to a carrier which is not itself significantly affected by this agent, the new, derived, hemolysin has been found not to be inactivated by the agent. The hemolysins of this group can thus be inactivated by enzymatic attack on the prosthetic group, or by hydrolysis or deformation of the postulated carrier molecule. VL - 118 IS - 6 ER - TY - JOUR T1 -

OXYGEN-STABLE HEMOLYSINS OF GROUP A STREPTOCOCCI. I. THE ROLE OF VARIOUS AGENTS IN THE PRODUCTION OF THE HEMOLYSINS

JF - The Journal of Experimental Medicine Y1 - 1963 A1 - Isaac Ginsburg A1 - T. N. Harris A1 - N. GROSSOWICZ AB - The production of oxygen-stable hemolysin in growing and resting Group A streptococci has been induced by RNA, by detergents, and by mammalian blood serum proteins, in the presence of glucose, Mg(++), and cysteine. Of the serum proteins, albumin and alpha lipoprotein could act as inducers. In the case of both these serum proteins treatment with trypsin did not affect the capacity to induce hemolysin production, but removal of the bound lipids by alcohol-ether or chloroform-methanol destroyed this property. In comparisons of the conditions of production and of activity between the hemolysin produced by RNA on one hand and albumin and detergents on the other, some data indicated similarities among the hemolysins, and others, differences. The similarities included similar degrees of temperature dependence for production and equal degrees of inhibition by serum beta lipoprotein. Differences found among these hemolysins included differences between, the rate of production of the RNA hemolysin from that of albumin or detergent hemolysin by both resting and growing streptococci, and the failure of utilization of glucosamine as an energy source for the production of albumin hemolysin, in contrast with that of RNA hemolysin. The fact that the data have in some cases indicated similarities and in other cases differences among the hemolysins raises the question of whether these are different molecular species, or a single hemolysin synthesized by the streptococci via different pathways of metabolism, or complexes of a single hemolytic moiety with various molecular carriers. VL - 1 IS - 118 ER - TY - JOUR T1 -

A thermostable cytotoxic factor in normal human serum active against Landschutz ascities tumor cells

JF - Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine Y1 - 1961 A1 - Isaac Ginsburg A1 - T. Dishon A1 - M. Block A1 - J. Gross AB - A heat stable factor (SF) in normal human serum which is cytotoxic to Landschutz ascites tumor cells has been described. The cytotoxic action requires the presence of human or rabbit complement but guinea pig complement is ineffective. The substance is found in the beta-globulin fraction and has characteristics similar to C′4 of human complement. It is selectively absorbed on human and mouse tumor cells and human placenta but not by normal human liver, kidney or heart. SF inhibits the action of heterologous antibody on ascites and HeLa cells. We are indebted to Dr. A. Rimon, Marcus Memorial Blood Bank Institute, Jaffa, for the Cohn fractions, and to Dr. Esther Tenenbaum of this Department for a generous supply of HeLa cells and Chang cells. VL - 107 ER - TY - JOUR T1 -

 

Effect of streptococcal haemolysins on Ehrlich ascites tumour cells

JF - The Journal of pathology and bacteriology Y1 - 1960 A1 - Isaac Ginsburg A1 - N. GROSSOWICZ VL - 80 IS - 1 ER - TY - JOUR T1 -

Action of Antibodies and Plasmin on Ehrlich Ascites Tumour Cells

JF - Nature Y1 - 1960 A1 - Isaac Ginsburg A1 - M. Ram AB - THE mechanism of cell destruction in allergic inflammation is not well understood. Two explanations for production of cell damage have, however, been proposed: (a) that the antigen-antibody reaction causes, in some non-specific manner, permeability changes in cells which result in the release of active mediators of inflammation (histamine, etc.) and that the latter are directly involved in the allergic process1; (b) that the antigen-antibody reaction activates proteolytic enzymes (plasmin, proteases) that injure the cells2–4. VL - 185 ER - TY - JOUR T1 -

Cardiac Lesions Produced in the Rabbit by Intramyocardial Injection of Various Micro-organisms

JF - International Journal of Experimental Pathology Y1 - 1960 A1 - Isaac Ginsburg A1 - A. Laufer A1 - S. Z. Rosenberg AB - SEVERAL studies were undertaken in order to reproduce in laboratory animals cardiac lesions which would resemble those appearing in human beings suffering from the sequelae of streptococcal infections (Schultz, 1936 ; Smith, Morgan and Mudd, 1940; Gross, Cooper and Philips, 1941; Robinson, 1947; Schultz, 1947; Murphy and Swift, 1949; Murphy, 1949; Clawson, 1950; Robinson, 1951; Murphy, 1952; Glaser, Thomas, Morse and Darnell, 1956). These studies describe the histopathological changes obtained in laboratory animals following inoculation by various routes of haemolytic streptococci, of their products and of a number of other micro-organisms. As to the mechanism involved in the production of cardiac lesions, two main theories have been proposed: (a)allergic phenomena,or production ofa uto- antibodies to the heart muscle (Rich and Gregory,1944; Rich,1946; Cavelty, 1947a and 1947b), (b) direct action of haemolytic streptococci and their toxins on the heart muscle (McLeod, 1953; Kellner and Robertson, 1954a and 1954b). Although both theories have been supported by some experimental evidence, the exact mechanism has not yet been clarified. This study describes the histo-pathological changes obtained in rabbits as a result of single intramyocardial injections of haemolytic streptococci and their cell-free extract, as well as of other bacterial species, both related and not related to haemolytic streptococci. The possible mechanism involved, and especially the role of trauma to the myocardium, in inducing cardiac lesions, is described. VL - 41 IS - 1 ER - TY - JOUR T1 -

Action of Phospholipids on the Cytotoxic Effect of Rabbit Antibodies Against Ehrlich Ascites Tumour Cells

JF - International Journal of Experimental Pathology Y1 - 1960 A1 - Isaac Ginsburg AB - STUDIES on the cytotoxic action of antibodies, plasmin and streptococcal haemolysins on Ehrlich ascites tumour cells (E-cells) have been recently described (GCinsburg, 1959; Ginsburg and Grossowicz, 1960; Ginsburg and Ram, 1960). It was found that the cytopathogenic changes induced in the tumour cells by streptococcal haemolysins were morphologically very similar to those caused by anti-Ehrlich ascites tumour rabbit serum (AE), the action of the latter is known to be complement dependent (Flax, 1956; Goldberg and Green, 1959). It is known that both the haemolytic as well as the cytopathogenic effect caused by streptococcal haemolysins can be inhibited by antihaemolytic agents such as cholesterol, lecithin, congo red and trypan blue (Van Heyningen, 1950; Bernheimer, 1954; Ginsburg, 1959; Ginsburg and Grossowicz, 1960). On the other hand, the cytotoxic and haemolytic effect of antibodies can be inhibited by agents known to destroy or inhibit complement action, chelating agents, plasmin, heparin etc. (Gorrill and Hobson, 1952; Pillemer, Ratnoff, Blum and Lepow, 1953; Mayer, 1 958; Ginsburg and Ram, 1960). The present study shows that the cytotoxic action of antibodies produced in the rabbit against Ehrlich ascites tumour cells can be inhibited by various phospholipids and some of their constituents as well as by agents known to inhibit streptococcal haemolysins. In addition the inhibition of immune haemolysis by phospholipids will be described. VL - 41 IS - 6 ER - TY - JOUR T1 -

Action of streptococcal haemolysins and proteolytic enzymes on Ehrlich ascites tumour cells

JF - British journal of experimental pathology Y1 - 1959 A1 - Isaac Ginsburg AB - IT has been recently shown that various strains of Streptococcus pyoqenes group A possess a cell-bound haemolysin (CBH) which can be released from the streptococcal cells into the surrounding medium by some surface active materials (Tween 40, Tween 80, Triton) by crystalline albumin, but not by sonlic energy (Ginsburg and Grossowicz, 1957 ; Ginsburg, 1958; Ginsburg and Grossowicz, 1959). This haemolytic factor was designated as streptolysin " D " (SLD) D signifying detergent. SLD is distinguished from streptolysin 0 (SLO) streptolysin S (SLS) (Todd, 1938) and from the intracellular haemolysin (IH) described by Schwab (Schwab, 1956) on the bases of different substrate requirements for formation, sensitivity to U.N. irradiation and to sonic energy (Ginsburg, 1958; Ginsburg and Gros- sowicz, unpublished). Besides haemolysing RBC of various animal species both cell-free and cell- bounid SLD, are also capable of injuring and killing various mamimalian cells in vitro (Ehrlich ascites tumour cells, fibroblasts, amnion cells, leucocytes) (Gins- buirg, 1958 ; Ginsburg and Grossowicz, 1959). The purpose of the present study is to show that Ehrlich ascites tuilour cells damaged by different streptococcal haemolysins may be disintegrated bv various proteolytic enzymes which by themselves are not lethal VL - 40 IS - 5 ER - TY - JOUR T1 -

A cell-bound hemolysin of group A streptococci

JF - Bulletin of the Research Council of Israel Y1 - 1958 A1 - Isaac Ginsburg A1 - N. GROSSOWICZ VL - Section E IS - Experimental medicine, December 1958, 7 ER - TY - JOUR T1 -

Group A hemolytic streptococci. I. A chemically defined medium for growth from small inocula

JF - Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine Y1 - 1957 A1 - Isaac Ginsburg A1 - N. GROSSOWICZ AB - 1) Defined media which allow heavy growth of 3 strains of group A streptococci have been developed. The medium consists of either a) 21 amino acids, glutamine, 6 vitamins, salts, purines, pyrimidines and glucose or b) 13 amino acids and 4 vitamins. 2) Cysteine is important both as an essential amino acid and as a reducing agent. As an amino acid only a small amount (10 μg ml) is needed and this can be substituted by an equivalent amount of cystine. As a reducing agent it can be replaced by ascorbic acid and less effectively by thiomalic or thioglycollic acids. Concentration of cysteine was critical for initiation of growth from small inocula. With less than 5 × 106 ml cells at least 350 μg ml cysteine HCl are needed for obtaining visible growth. 3) Pyridoxal was necessary in a medium of 13 amino acids and 3 vitamins (nicotinic acid, pantothenate, riboflavin) whereas in a complete medium (22 amino acids) no need for pyridoxal was found. Pyridoxal could be replaced by L- or DL-alanine. VL - 96 IS - 1 ER - TY - JOUR T1 -

THE EFFECT OF SODIUM a-ACETONYLBENZYL-4-HYDROXY CUMARIN (SODIUM WARFARIN) AND OF ACUTE BLOOD LOSS ON LOCALIZED INFLAMMATION IN THE LIVER INDUCED BY IMPLANTED SURGICAL GUT

JF - Bulletin of the Research Council of Israel Y1 - 1956 A1 - Isaac Ginsburg A1 - H. Ungar VL - 6E IS - 1 ER - TY - JOUR T1 -

The effect of trypsin on localized inflammation in the liver

JF - Bulletin of the Research Council of Israel Y1 - 1955 A1 - H. Ungar A1 - Isaac Ginsburg VL - 5B IS - 2 ER - TY - JOUR T1 -

Studieso on fibrinolytic enzymes in patients undergoing thoracic surgery

JF - The Journal of Thoracic Surgery Y1 - 1955 A1 - H. MILWIDSKY A1 - Isaac Ginsburg A1 - A. DE VRIES VL - 29 IS - 6 ER - TY - JOUR T1 -

The action of some water-soluble poly-alpha-amino acids on fibrinolysis

JF - Science Y1 - 1952 A1 - Isaac Ginsburg A1 - A. DE-VRIES A1 - E. KATCHALSKI AB - During our study of the action of water-soluble poly-a-amino acids on blood clotting (1), it was observed that the basic poly-amino acids: poly-lysine (2), poly-ornithine (3) and poly-arginine (3), retard fibrinolysis of human clotted blood. A more detailed analysis of this phenomenon was therefore undertaken. Fibrinolytic activity of oxalated human plasma was induced by mixing the plasma with a suspension of ,- hemolytic streptococci (4, 5), by treatment with a cellfree broth containing streptokinase (6), or by shaking the plasma with chloroform (6, 7). The activated plasma was then treated with the poly-amino acids (prepared in this laboratory), and a fibrin clot obtained by the addition of thrombin. The final mixtures were incubated at 370 C for 15-24 hr to determine -if lysis occurred. When the preparations used did not interfere with fibrinolysis, dissolution of the clot occurred. Inhibition of fibrinolysis was indicated by the maintenance of the fibrin clot, obtained as described *above, for 24 hr. A typical experiment with poly-L-lysine and a streptococei-activated plasma is described below. Oxalated human plasma (0.5 ml) was mixed with a suspension of 1-hemolytic streptococci (0.4 ml), and the mixture added to 1 ml saline solution containing 40y poly-L-lysine hydrochloride. Clotting was induced by adding 4 units of bovine thrombin (Upjohn Company) in 0.1 ml saline with vigorous shaking. The clot was incubated at 370 C for 24 hr. No visual change in the clot was observed. In the control experiment where the 1 ml poly-lysine solution was substituted by saline, a complete lysis of the clot was evident within 30 min. The fibrinolytic activity of plasma activated by Ihemolytic streptococci was not inhibited either by the neutral poly-DL-alanine (8) or by the acidic poly-Laspartic (9) and poly-D-glutamic (10) acids up to concentrations of 500y/ml final test mixture. The basic poly-a-amino acids, poly-DL-lysine hydrochloiide (average chain length n = 35) (2), poly-DL-ornithine hydrochloride (n = 30) (3), and poly-DL-arginine sulfate (n = 30) (3), on the other hand, prevented fibrinolysis at concentrations greater than 30y40y/ml test mixture. In the presence of the basic poly-amino acids, fibrinolysis Was inhibited equally well when the streptococcal culture suspension was replaced (in the test mixture) by a cell-free supernatant containing streptokinase. Furthermore, it has been demonstrated that the fibrinolytic activity of chloroform-treated plasma and of menstrual blood was also inhibited by relatively low concentrations of poly-DL-lysine and poly- DL-arginine. It thus seems justified to assume that the basic poly-amino acids are capable of inhibiting hydrolysis of fibrin by plasma fibrinolysin (plasmin) under the experimental conditions used. Preliminary experiments indicated that the average molecular weight of the basic poly-amino acids plays a profound role in ther determination of their antifibrinolytic properties. L-lysine monomer, as well as L-lysyl-L-lysine (11), did not show any antifibrinolytic activity up to a concentration of 750y/ml. A tetra-Llysine showed slight antifibrinolytic activity at 750y/ ml, whereas poly-L-lysine of average chain length n= 7, 35, and 100 showed distinct antifibrinolytic activity at concentrations of 500y, 40y, and 35y/ml test mixture, respectively. No great difference was observed in the antifibrinolytic activity of poly-L-, poly-D-, and poly-DL-lysine of similar average molecular weights. In our previous study on the action of water-soluble poly-amino acids on blood clotting (1), it was demonstrated that the acidic poly-amino acids, poly-D-glutamic acid and poly-L-aspartic acid, as well as heparin, are capable of neutralizing the anticoagulant activity of the basic poly-amino acids. A similar relationship was found to hold for the antifibrinolytic effect of the basic poly-amino acids. Heparin, as well as poly-Laspartic acid (n = 50), was found to obviate the antifibrinolytic activity of poly-lysine. The neutralization of the antifibrinolytic activity of the basic poly-amino acids occurred when approximately equivalent concentrations of the basie -and acidic poly-amino acids were applied. The ability of the basic synthetic peptides to inhibit rev,ersibly the. proteolytic activity of fibrinolysin resembles, the antiproteolytic properties of some natural peptides, such as the pepsin,inhibitor and the' trypsin inhibitors (12). The interaction of the natural as well as the synthetic peptides with the different proteolytic enzymes is probably determined in both cases by some specific groups present in the enzyme and the inhibitor, as well as by the electrostatic forces prevailing between the enzyme and the relatively high molecular weight inhibitor. Further studies with the 'synthetic amino acid polymers may contribute to our basic knowledge of the mode of actlon of naturally naturally occurring polypeptides on enzyme behavior. VL - 116 IS - 3001 ER -