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Full-Text Articles in Immunology and Infectious Disease
Inhibitory Effect Of Monocyte Reactive Antibodies On Monocyte Chemotaxis In Systemic Lupus Erythematosus, Gyula Szegedi, Katalin Lukacs, E. Bodolay, L. Gulacsi, Ildiko Sonkoly, Gyongyi Szabo, J. Szollosi
Inhibitory Effect Of Monocyte Reactive Antibodies On Monocyte Chemotaxis In Systemic Lupus Erythematosus, Gyula Szegedi, Katalin Lukacs, E. Bodolay, L. Gulacsi, Ildiko Sonkoly, Gyongyi Szabo, J. Szollosi
Gyongyi Szabo
Presence of different types of autoantibodies is a basic feature of systemic lupus erythematosus (SLE). Though monocytes, macrophages play an important role in cellular immunity, autoantibodies against monocytes have not been sufficiently studied. The authors used automatic fluorochromatic assay to detect monocyte reactive autoantibodies in the sera of SLE patients. Of SLE 35.5% sera showed complement-mediated monocytotoxic activity against healthy monocytes. Monocyte reactive SLE sera as well as monoclonal antibodies against human monocytes inhibited chemotaxis of control monocytes. The results suggest that monocyte reactive autoantibodies may play a role in the decreased monocyte number and defective monocyte functions observed in …
Regulation Of Human Monocyte Functions By Acute Ethanol Treatment: Decreased Tumor Necrosis Factor-Alpha, Interleukin-1 Beta And Elevated Interleukin-10, And Transforming Growth Factor-Beta Production, Gyongyi Szabo, Pranoti Mandrekar, Linda Girouard, Donna Catalano
Regulation Of Human Monocyte Functions By Acute Ethanol Treatment: Decreased Tumor Necrosis Factor-Alpha, Interleukin-1 Beta And Elevated Interleukin-10, And Transforming Growth Factor-Beta Production, Gyongyi Szabo, Pranoti Mandrekar, Linda Girouard, Donna Catalano
Gyongyi Szabo
We and others have previously shown that even acute ethanol exposure has the capacity to modulate immune functions, particularly monocyte functions. Herein, we tested the hypothesis that acute ethanol treatment inhibits inflammatory, while increasing inhibitory cytokine production in human blood monocytes that, in turn, could contribute to the overall immune abnormalities seen after alcohol use. Our data show that in vitro treatment of blood monocytes with a physiologically relevant dose of alcohol (25 mM) results in significantly decreased induction of tumor necrosis factor-alpha (TNF alpha) and interleukin (IL)-1 beta by bacterial stimulation of either Gram-positive [staphylococcal enterotoxin B (SEB), 1 …
Monocytes, Alcohol Use, And Altered Immunity, Gyongyi Szabo
Monocytes, Alcohol Use, And Altered Immunity, Gyongyi Szabo
Gyongyi Szabo
The immunomodulatory capacity of acute, moderate alcohol consumption was investigated in this study in nonalcoholic volunteers after 2 ml of vodka/kg body weight of alcohol consumption. There was a significant, transient increase in interleukin-12 and interferon-gamma (IFNgamma) levels in whole blood samples collected 4 hr after alcohol consumption in response to an ex vivo bacterial challenge with lipopolysaccharide (p < 0.02). However, decreased IFNgamma levels were produced by mononuclear cells collected later after alcohol consumption (16 hr), suggesting that acute alcohol consumption has a biphasic effect on IFNgamma inducibility. Furthermore, isolated blood monocytes collected 16 hr after alcohol consumption showed significantly …
Human Monocytes, Macrophages, And Dendritic Cells: Alcohol Treatment Methods, Gyongyi Szabo, Pranoti Mandrekar
Human Monocytes, Macrophages, And Dendritic Cells: Alcohol Treatment Methods, Gyongyi Szabo, Pranoti Mandrekar
Gyongyi Szabo
Both acute and chronic alcohol consumption have significant immunomodulatory effects of which alterations in innate immune functions contribute to impaired antimicrobial defense and inflammatory responses. Blood monocytes, macrophages, and dendritic cells play a central role in innate immune recognition as these cells recognize pathogens, respond with inflammatory cytokine production, and induce antigen-specific T-lymphocyte activation. All of these innate immune cell functions are affected in humans by alcohol intake. Here, we summarize the different effects of acute and chronic alcohol on monocyte, macrophage, and dendritic cell functions in humans and describe methods for separation and functional evaluation of these cell types.
Antigen-Presenting Cells Under The Influence Of Alcohol, Audrey Lau, Gyongyi Szabo, Angus Thomson
Antigen-Presenting Cells Under The Influence Of Alcohol, Audrey Lau, Gyongyi Szabo, Angus Thomson
Gyongyi Szabo
The negative influence of alcohol (ethanol) and its metabolites on innate and adaptive immunity is well-recognized. Much attention has recently been focused on the impact of acute and chronic alcohol exposure on antigen-presenting cells (APC). In particular, insights have been gained into how the properties of human blood monocytes and rodent macrophages are influenced by alcohol in vitro and in vivo. Here, we review the impact of alcohol on various aspects of APC function and the underlying mechanisms, including its effects on intracellular signaling events. We also discuss new information regarding the influence of alcohol on various APC populations in …
Alcohol-Induced Modulation Of Signaling Pathways In Liver Parenchymal And Nonparenchymal Cells: Implications For Immunity, Bharath Nath, Gyongyi Szabo
Alcohol-Induced Modulation Of Signaling Pathways In Liver Parenchymal And Nonparenchymal Cells: Implications For Immunity, Bharath Nath, Gyongyi Szabo
Gyongyi Szabo
Alcoholic liver injury involves a complex array of derangements in cellular signaling of hepatic parenchymal and nonparenchymal cells as well as cells of the immune system. In the hepatocyte, chronic ethanol abuse leads to lipid accumulation and liver steatosis. Multiple pathways are affected to promote lipid accumulation in the ethanol-exposed hepatocyte. Chronic ethanol renders Kupffer cells hyperresponsive to endotoxin, which results in production of inflammatory cytokines and the tumor necrosis factor-alpha via a toll-like receptor 4 dependent pathway, leading to inflammation and hepatic necrosis. Dysfunction of the innate and adaptive immune responses caused by ethanol contributes to impaired antiviral response, …
Polymorphonuclear Functions In Patients With Mixed Connective Tissue Disease, E. Bodolay, Katalin Lukacs, G. Frendl, Gyongyi Szabo, G. Arato, Gyula Szegedi
Polymorphonuclear Functions In Patients With Mixed Connective Tissue Disease, E. Bodolay, Katalin Lukacs, G. Frendl, Gyongyi Szabo, G. Arato, Gyula Szegedi
Gyongyi Szabo
Polymorphonuclear leukocytes (PMNs) from 29 patients with mixed connective tissue disease (MCTD) were studied "in vitro" for their phagocytic and chemotactic function as well as for granulocyte alkaline phosphatase (GAP) activity. Fc-receptor expression detected by EA-rosette formation was comparable to the control. Yeast-phagocytosis, C3b-receptor mediated phagocytosis and chemotaxis of PMNs, however, significantly decreased in MCTD. At the same time, photometric measure of alkaline phosphatase activity indicated a nearly two fold increase in PMNs from patients with MCTD. Although no correlation was found between PMN functions and the activity of the disease, PMN disorders may play a role in pathogenesis of …
Acute Alcohol Inhibits The Induction Of Nuclear Regulatory Factor Kappa B Activation Through Cd14/Toll-Like Receptor 4, Interleukin-1, And Tumor Necrosis Factor Receptors: A Common Mechanism Independent Of Inhibitory Kappa B Alpha Degradation, Pranoti Mandrekar, Angela Dolganiuc, Gary Bellerose, Karen Kodys, Laszlo Romics, Rabia Nizamani, Gyongyi Szabo
Acute Alcohol Inhibits The Induction Of Nuclear Regulatory Factor Kappa B Activation Through Cd14/Toll-Like Receptor 4, Interleukin-1, And Tumor Necrosis Factor Receptors: A Common Mechanism Independent Of Inhibitory Kappa B Alpha Degradation, Pranoti Mandrekar, Angela Dolganiuc, Gary Bellerose, Karen Kodys, Laszlo Romics, Rabia Nizamani, Gyongyi Szabo
Gyongyi Szabo
BACKGROUND: Nuclear translocation and DNA binding of the nuclear factor kappaB (NF-kappaB) is an early event in inflammatory cell activation in response to stimulation with bacterial components or cytokines. Cell activation via different receptors culminates in a common pathway leading to NF-kappaB activation and proinflammatory cytokine induction. We have previously shown that acute alcohol inhibits NF-kappaB activation by lipopolysaccharide (LPS) in human monocytes. Here we investigated whether acute alcohol treatment of human monocytes also inhibits NF-kappaB when induced through activation of the interleukin (IL)-1 or tumor necrosis factor (TNF) receptors. METHODS: Human peripheral blood monocytes were treated with LPS, TNFalpha, …
Monocyte Functions In Patients With Mixed Connective Tissue Disease, E. Bodolay, Katalin Lukacs, Gyongyi Szabo, G. Frendl, T. Ben, Gyula Szegedi
Monocyte Functions In Patients With Mixed Connective Tissue Disease, E. Bodolay, Katalin Lukacs, Gyongyi Szabo, G. Frendl, T. Ben, Gyula Szegedi
Gyongyi Szabo
The authors investigated the number and functions of peripheral blood monocytes in patients with mixed connective tissue disease. Moderate monocytopenia was detected in the active stage of the disease. There was a close correlation between the sensitized sheep red blood cell binding capacity of monocytes and the elevated levels of circulating immune complexes. The yeast phagocytosis of monocytes and the chemotactic activity were normal in patients with mixed connective tissue disease. C3b receptor mediated phagocytosis of monocytes decreased in the active and inactive stages of the disease. This study suggests that the decreased function of C3b receptors of monocytes is …
Human Macrophages Degrade Tryptophan Upon Induction By Interferon-Gamma, Ernst Werner, Gabriele Bitterlich, Dietmar Fuchs, Arno Hausen, Gilbert Reibnegger, Gyongyi Szabo, Manfred Dierich, Helmut Wachter
Human Macrophages Degrade Tryptophan Upon Induction By Interferon-Gamma, Ernst Werner, Gabriele Bitterlich, Dietmar Fuchs, Arno Hausen, Gilbert Reibnegger, Gyongyi Szabo, Manfred Dierich, Helmut Wachter
Gyongyi Szabo
Human peripheral blood mononuclear cells, monocytes-macrophages and T-cells were stimulated with human recombinant interferon-gamma, interferon-alpha and phytohemagglutinin. The culture supernatants were analyzed for tryptophan, kynurenine, 3-hydroxyanthranilic acid, anthranilic acid and neopterin by high performance liquid chromatography. Tryptophan was decreased and the four other compounds were increased in supernatants of peripheral blood mononuclear cells activated by interferon-gamma (250 U/ml), interferon-alpha (10.000 U/ml) and phytohemagglutinin (1 microgram/ml). After splitting of peripheral blood mononuclear cells by adherence, the monocytes and macrophages but not the T-cells degraded tryptophan upon stimulation by interferon-gamma in a dose dependent manner. Supernatants of phytohemagglutinin stimulated but not of …
New Insights Into The The Molecular Mechanisms Of Alcoholic Hepatitis: A Potential Role For Nf-Kappab Activation, Gyongyi Szabo
New Insights Into The The Molecular Mechanisms Of Alcoholic Hepatitis: A Potential Role For Nf-Kappab Activation, Gyongyi Szabo
Gyongyi Szabo
No abstract provided.
Regulation Of Monocyte Interleukin-12 Production By Acute Alcohol: A Role For Inhibition By Interleukin-10, Linda Girouard, Pranoti Mandrekar, Donna Catalano, Gyongyi Szabo
Regulation Of Monocyte Interleukin-12 Production By Acute Alcohol: A Role For Inhibition By Interleukin-10, Linda Girouard, Pranoti Mandrekar, Donna Catalano, Gyongyi Szabo
Gyongyi Szabo
Acute ethanol treatment results in decreased antigen presentation capacity (Th1-type immunity) and elevated interleukin IL-10 (Th2 cytokine) production in human monocytes. Monocytes can contribute to both Th1 (IL-12) and Th2 (IL-10) immune responses via production of IL-12 and IL-10, respectively. Thus, we tested the hypothesis that acute alcohol treatment might affect Th1/Th2 immune balance by altering monocyte production of IL-12 and IL-10. Neither acute ethanol treatment alone (25 to 100 mM) nor its combination with a bacterial challenge Staphylococcal enterotoxin B (SEB) induced IL-12 production in isolated blood monocytes. In contrast, the same physiological alcohol concentrations increased monocyte IL-10 levels, …
Hepatitis C Core And Nonstructural 3 Proteins Trigger Toll-Like Receptor 2-Mediated Pathways And Inflammatory Activation, Angela Dolganiuc, Shilpa Oak, Karen Kodys, Douglas Golenbock, Robert Finberg, Evelyn Kurt-Jones, Gyongyi Szabo
Hepatitis C Core And Nonstructural 3 Proteins Trigger Toll-Like Receptor 2-Mediated Pathways And Inflammatory Activation, Angela Dolganiuc, Shilpa Oak, Karen Kodys, Douglas Golenbock, Robert Finberg, Evelyn Kurt-Jones, Gyongyi Szabo
Gyongyi Szabo
BACKGROUND AND AIMS: Recent evidence suggests that toll-like receptors (TLRs) recognize certain viruses. We reported that hepatitis C virus (HCV) core and nonstructural 3 (NS3) proteins activate inflammatory pathways in monocytes. The aim of this study was to investigate the role of TLRs in innate immune cell activation by core and NS3 proteins. METHODS: Human monocytes, human embryonic kidney cells transfected with TLR2, and peritoneal macrophages from TLR2, MyD88 knockout, and wild-type mice were studied to determine intracellular signaling and proinflammatory cytokine induction by HCV proteins. RESULTS: HCV core and NS3 proteins triggered inflammatory cell activation via the pattern recognition …
Subversion Of Plasmacytoid And Myeloid Dendritic Cell Functions In Chronic Hcv Infection, Gyongyi Szabo, Angela Dolganiuc
Subversion Of Plasmacytoid And Myeloid Dendritic Cell Functions In Chronic Hcv Infection, Gyongyi Szabo, Angela Dolganiuc
Gyongyi Szabo
Insufficient elimination of the hepatitis C virus (HCV) during acute infection results in chronic disease in the majority of patients due to weak virus-specific immune responses. Dendritic cells (DC) play a central role in recognition of HCV and in induction of innate and adaptive immune responses. In this study, we evaluated the frequency and functions of plasmacytoid dendritic cells (PDC) and myeloid dendritic cells (MDC) in patients with chronic HCV infection. We found that both the numbers and IFNalpha production capacity of blood PDC were significantly reduced in patients with chronic HCV infection compared to normal controls. While the frequency …
Inhibition Of Antigen-Presenting Cell Functions By Alcohol: Implications For Hepatitis C Virus Infection, Gyongyi Szabo, Angela Dolganiuc, Pranoti Mandrekar, Bernadette White
Inhibition Of Antigen-Presenting Cell Functions By Alcohol: Implications For Hepatitis C Virus Infection, Gyongyi Szabo, Angela Dolganiuc, Pranoti Mandrekar, Bernadette White
Gyongyi Szabo
The mechanisms of alcohol-induced immunosuppression include defects in innate and adaptive immune responses. Monocytes and dendritic cells (DCs) link innate and adaptive immune responses as they recognize viral antigens and induce antigen-specific T-cell activation. We investigated the effects of alcohol on antigen-presenting cell functions. Acute alcohol consumption by healthy volunteers (vodka, 2 ml/kg) resulted in significantly reduced antigen-presenting cell function of monocyte-derived DCs. Reduced allostimulatory capacity of DCs treated with alcohol in vitro correlated with decreased co-stimulatory molecule (B7.1 and B7.2) expression, as well as with reduced interleukin (IL)-12 and increased IL-10 concentrations, in mixed lymphocyte cultures. Dendritic cells recognize …
Regulation Of Monocyte Il-12 Production: Augmentation By Lymphocyte Contact And Acute Ethanol Treatment, Inhibition By Elevated Intracellular Camp, Gyongyi Szabo, Linda Girouard, Pranoti Mandrekar, Donna Catalano
Regulation Of Monocyte Il-12 Production: Augmentation By Lymphocyte Contact And Acute Ethanol Treatment, Inhibition By Elevated Intracellular Camp, Gyongyi Szabo, Linda Girouard, Pranoti Mandrekar, Donna Catalano
Gyongyi Szabo
IL-12, a monocyte-derived cytokine, is pivotal in activation of cellular immune response and inflammation. Both inflammatory response and cellular immunity are impaired by acute ethanol consumption. Here, we found that in vitro acute ethanol treatment (25-100 mM) results in a dose-dependent and significant increase of IL-12 in IFN-gamma (100 U/ml) plus Staphylococcal enterotoxin B (SEB; 1 microg/ml) stimulated monocytes and mononuclear cells but not in unstimulated cells from non-alcoholic blood donors. There was significantly greater IL-12 production in the MNC population compared to isolated Mphi (P < 0.001). Prevention of monocyte surface contact with either purified T lymphocytes or monocyte-depleted MNC resulted in a significant, 65+/-20%, decrease in IL-12 production regardless of IFN-gamma, SEB or ethanol stimulation suggesting that Mphi T-cell surface contact provides an additional signal for IL-12 production. In addition to cell surface contact, soluble mediators, particularly IL-10 and PGE2 may regulate IL-12 production. The cyclooxygenase inhibitor, Indomethacin (10(-6)M), augmented both IL-12 and IL-10 levels in isolated monocytes and mononuclear cells whether induced by medium, SEB or SEB plus 25 mM ethanol suggesting that regulation of IL-12 production via the cyclooxygenase pathway is independent of IL-10. Finally, elevation of intracellular cAMP levels by dbcAMP treatment consistently inhibited IL-12 as well as IL-10 production in monocytes induced by IFN-gamma or IFN-gamma plus 25 mM ethanol. These data suggest that augmentation of monocyte IL-12 by acute ethanol is not mediated via the cAMP pathway.
The Role Of Plasmacytoid Dendritic Cell-Derived Ifn Alpha In Antiviral Immunity, Gyongyi Szabo, Angela Dolganiuc
The Role Of Plasmacytoid Dendritic Cell-Derived Ifn Alpha In Antiviral Immunity, Gyongyi Szabo, Angela Dolganiuc
Gyongyi Szabo
Viral infections represent a major source of acute and chronic human disease. The immune system plays a central role in the elimination of viruses through its ability to recognize pathogens and to induce virus-specific cellular activation, accompanied by a robust production of soluble molecules with antiviral effects. Interferons are among the most powerful natural soluble antiviral molecules. Upon viral infection, interferons are produced by a variety of cell types, with immune cells being the main contributors. The immune system works as a well-orchestrated team composed of multiple cell types. The mechanisms of intercellular cooperation that includes dendritic cells (DCs), their …
Ethanol-Mediated Regulation Of Transcription Factors In Immunocompetent Cells, Gyongyi Szabo, Pranoti Mandrekar
Ethanol-Mediated Regulation Of Transcription Factors In Immunocompetent Cells, Gyongyi Szabo, Pranoti Mandrekar
Gyongyi Szabo
The immunomodulatory effects of acute and chronic alcohol use are characterized by impaired antigen-specific immune activation and by increased susceptibility to infections due to alterations in innate immune responses and inflammatory mediator production. The central feature of cellular responses to inflammatory and stress signals is the activation of the nuclear regulatory kappa B/Rel family of transcriptional factors via various surface receptor systems in immunocompetent cells. Activation of NF-kappa B, however, is regulated at multiple levels including I-kappa B degradation, nuclear translocation, and by interaction of NF-kappa B/Rel with other transcription factors. Data from our and other laboratories demonstrate that acute …
Selective Induction Of Mononuclear Phagocytes To Produce Neopterin By Interferons, Gabriele Bitterlich, Gyongyi Szabo, Ernst Werner, C. Larcher, Dietmar Fuchs, Arno Hausen, Gilbert Reibnegger, T.F. Schulz, J. Troppmair, Helmut Wachter
Selective Induction Of Mononuclear Phagocytes To Produce Neopterin By Interferons, Gabriele Bitterlich, Gyongyi Szabo, Ernst Werner, C. Larcher, Dietmar Fuchs, Arno Hausen, Gilbert Reibnegger, T.F. Schulz, J. Troppmair, Helmut Wachter
Gyongyi Szabo
Interferon-gamma (IFN-gamma) has been shown to be a potent inducer of neopterin secretion by human peripheral blood monocytes/macrophages (1). In this paper, it is shown that other known stimuli of monocytes (e.g., to secrete proteases or to migrate) such as zymosan-activated human serum, lipopolysaccharide, human C3/iC3 and zymosan coated with complement were unable to trigger monocytes/macrophages to release neopterin. Monocytes/macrophages could be stimulated solely by IFN-gamma (25 U/ml) and IFN-alpha at very high concentrations (10,000 U/ml). In the case of human peripheral blood mononuclear cells (PBMNC), basically the same pattern was observed. If however, in the buffer controls PBMNC showed …
Hepatitis C Virus Ns5a Protein--A Master Regulator, Gyongyi Szabo
Hepatitis C Virus Ns5a Protein--A Master Regulator, Gyongyi Szabo
Gyongyi Szabo
No abstract provided.
Acute Ethanol Treatment Modulates Toll-Like Receptor-4 Association With Lipid Rafts, Angela Dolganiuc, Genadyi Bakis, Karen Kodys, Pranoti Mandrekar, Gyongyi Szabo
Acute Ethanol Treatment Modulates Toll-Like Receptor-4 Association With Lipid Rafts, Angela Dolganiuc, Genadyi Bakis, Karen Kodys, Pranoti Mandrekar, Gyongyi Szabo
Gyongyi Szabo
BACKGROUND: Alcohol, a substance that is most frequently abused, suppresses innate immune responses to microbial pathogens. The host senses pathogens via Toll-like receptors (TLRs). Recent studies indicate that alcohol affects TLR signaling. METHODS: Here, we hypothesized that acute alcohol treatment may interfere with early steps of membrane-associated TLR2 and TLR4 signaling at the level of lipid rafts. Human monocytes and Chinese hamster ovary (CHO) cells, transfected with human TLR2, TLR4, or CD14, were stimulated with peptidoglycan (PGN, TLR2 ligand) or lipopolysaccharide (LPS, TLR4 ligand) with or without alcohol (50 mM) and analyzed for cytokine production (enzyme-linked immunosorbent assay), nuclear factor-kappaB …
Hepatitis C And Innate Immunity: Recent Advances, Gyongyi Szabo, Angela Dolganiuc
Hepatitis C And Innate Immunity: Recent Advances, Gyongyi Szabo, Angela Dolganiuc
Gyongyi Szabo
Eradication of hepatitis C virus (HCV) infection requires a complex and coordinated interplay between innate and adaptive immune responses that, when it fails, leads to chronic infection. In this review, the innate immune mechanisms by which HCV is sensed and by which HCV undermines host defense are discussed. The critical role of dendritic cells in antigen presentation and T-cell activation in addition to type I interferon production and interference of HCV with innate immune cell functions are reviewed. Finally, current and emerging therapeutic approaches targeting innate immune pathways are evaluated.