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Inhibition Of Antigen-Presenting Cell Functions By Alcohol: Implications For Hepatitis C Virus Infection, Gyongyi Szabo, Angela Dolganiuc, Pranoti Mandrekar, Bernadette White Apr 2010

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 Apr 2010

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 Apr 2010

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 Apr 2010

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 …


Microrna Expression Profile In Lieber-Decarli Diet-Induced Alcoholic And Methionine Choline Deficient Diet-Induced Nonalcoholic Steatohepatitis Models In Mice, Angela Dolganiuc, Jan Petrasek, Karen Kodys, Donna Catalano, Pranoti Mandrekar, Arumugam Velayudham, Gyongyi Szabo Apr 2010

Microrna Expression Profile In Lieber-Decarli Diet-Induced Alcoholic And Methionine Choline Deficient Diet-Induced Nonalcoholic Steatohepatitis Models In Mice, Angela Dolganiuc, Jan Petrasek, Karen Kodys, Donna Catalano, Pranoti Mandrekar, Arumugam Velayudham, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND: Alcoholic and nonalcoholic steatohepatitis are leading causes of liver diseases worldwide. While of different etiology, these share common pathophysiological mechanisms and feature abnormal fat metabolism, inflammation and fibrosis. MicroRNAs (miRNA) are highly conserved noncoding RNAs that control gene expression at the post-transcriptional level either via the degradation of target mRNAs or the inhibition of translation. Each miRNA controls the expression of multiple targets; miRNAs have been linked to regulation of lipid metabolism and inflammation. METHODS: We fed Lieber-DeCarli alcohol or methionine-choline-deficient (MCD) diets to C57Bl6 and analyzed livers for histopathology, cytokines by ELISA, alanine aminotransferase (ALT) by biochemical assay, …


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 Apr 2010

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 …


Modulation Of Non-Alcoholic Steatohepatitis By Pattern Recognition Receptors In Mice: The Role Of Toll-Like Receptors 2 And 4, Gyongyi Szabo, Arumugam Velayudham, Laszlo Romics, Pranoti Mandrekar Apr 2010

Modulation Of Non-Alcoholic Steatohepatitis By Pattern Recognition Receptors In Mice: The Role Of Toll-Like Receptors 2 And 4, Gyongyi Szabo, Arumugam Velayudham, Laszlo Romics, Pranoti Mandrekar

Gyongyi Szabo

Toll-like receptors (TLR) recognize pathogen-derived molecules and induce downstream activation of inflammatory pathways. Fatty liver has been shown to result in increased sensitivity to lipopolysaccharide (LPS), a TLR4 ligand. In this study, we investigated the roles of TLR2 and TLR4 in liver damage and on cytokine induction in a methionine-choline deficient (MCD) diet-induced model of nonalcoholic steatohepatitis. We found that mice with nonalcoholic fatty liver had increased liver injury and inflammatory cytokine induction after challenge with a TLR4 but not with a TLR2 ligand. TLR2 deficient mice were not protected against the development of steatohepatitis after MCD diet feeding. On …


The Critical Role Of Toll-Like Receptor (Tlr) 4 In Alcoholic Liver Disease Is Independent Of The Common Tlr Adapter Myd88, Istvan Hritz, Pranoti Mandrekar, Arumugam Velayudham, Donna Catalano, Angela Dolganiuc, Karen Kodys, Evelyn Kurt-Jones, Gyongyi Szabo Apr 2010

The Critical Role Of Toll-Like Receptor (Tlr) 4 In Alcoholic Liver Disease Is Independent Of The Common Tlr Adapter Myd88, Istvan Hritz, Pranoti Mandrekar, Arumugam Velayudham, Donna Catalano, Angela Dolganiuc, Karen Kodys, Evelyn Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

The Toll-like receptor 4 (TLR4) that recognizes endotoxin, a trigger of inflammation in alcoholic liver disease (ALD), activates two signaling pathways utilizing different adapter molecules: the common TLR adapter, myeloid differentiation factor 88 (MyD88), or Toll/interleukin immune-response-domain-containing adaptor inducing interferon (IFN)-beta. The MyD88 pathway induces proinflammatory cytokine activation, a critical mediator of ALD. Here we evaluated the role of MyD88 in alcohol-induced liver injury in wild-type, TLR2-deficient, TLR4-deficient, or MyD88-deficient (knockout [KO]) mice after administration of the Lieber-De-Carli diet (4.5% volume/volume ethanol) or an isocaloric liquid control diet for 5 weeks. Alcohol feeding resulted in a significant increase in serum …


Hepatitis C Virus Ns5a Protein--A Master Regulator, Gyongyi Szabo Apr 2010

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 Apr 2010

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 …


Antigen Presentation By The Cd4 Positive Monocyte Subset, Gyongyi Szabo, Carol Miller-Graziano, Karen Kodys Apr 2010

Antigen Presentation By The Cd4 Positive Monocyte Subset, Gyongyi Szabo, Carol Miller-Graziano, Karen Kodys

Gyongyi Szabo

Although CD4 antigen is expressed on monocytes (MO), its functional role is uncharacterized. In this study, isolated human MO were separated into CD4+ and CD4- MO subsets and assessed for presentation of tetanus toxoid. The CD4- MO subset had decreased antigen presenting cell (APC) capacity as well as increased PGE2 production when compared to the CD4+ MO subset. Addition of a cyclo-oxygenase inhibitor (Indomethacin) did not restore the CD4- MO subset's APC capacity to that of the similarly treated CD4+ MO subset, eliminating differential PGE2 production as the primary cause of differential APC capacity. Production of monokines such as IL-1 …


Fcgammar Cross-Linking Mediates Nf-Kappab Activation, Reduced Antigen Presentation Capacity, And Decreased Il-12 Production In Monocytes Without Modulation Of Myeloid Dendritic Cell Development, Yvonne Drechsler, Sangeeta Chavan, Donna Catalano, Pranoti Mandrekar, Gyongyi Szabo Apr 2010

Fcgammar Cross-Linking Mediates Nf-Kappab Activation, Reduced Antigen Presentation Capacity, And Decreased Il-12 Production In Monocytes Without Modulation Of Myeloid Dendritic Cell Development, Yvonne Drechsler, Sangeeta Chavan, Donna Catalano, Pranoti Mandrekar, Gyongyi Szabo

Gyongyi Szabo

Stimulation of monocytes (MO) through receptors for the Fc region of immunoglobulin G (FcgammaR) activates a variety of responses, including phagocytosis, antibody (Ab)-dependent cellular cytotoxicity, and production of cytokines. We previously reported that the MO subpopulation that expresses FcgammaR in high density produces high levels of tumor necrosis factor alpha (TNF-alpha) compared with FcgammaR-negative MO. Here, we show that cross-linking MO via FcgammaRI or FcgammaRII but not via FcgammaRIII activates nuclear regulatory factor-kappaB (NF-kappaB), a transcription factor involved in regulation of TNF-alpha. NF-kappaB activation peaked at 2.75 h after FcgammaRI cross-linking, involved p65 and p50 (heterodimer) and not c-rel-containing NF-kappaB …


T Cells With Regulatory Activity In Hepatitis C Virus Infection: What We Know And What We Don't, Angela Dolganiuc, Gyongyi Szabo Apr 2010

T Cells With Regulatory Activity In Hepatitis C Virus Infection: What We Know And What We Don't, Angela Dolganiuc, Gyongyi Szabo

Gyongyi Szabo

The mechanism behind the apparent lack of effective antiviral immune response in patients with chronic hepatitis C virus (HCV) infection is poorly understood. Although multiple levels of abnormalities have been identified in innate and adaptive immunity, it remains unclear if any of the subpopulations of T cells with regulatory capacity (Tregs) contribute to the induction and maintenance of HCV persistence. In this review, we summarize the current knowledge about Tregs as they relate to HCV infection.


Acute Alcohol Exposure Exerts Anti-Inflammatory Effects By Inhibiting Ikappab Kinase Activity And P65 Phosphorylation In Human Monocytes, Pranoti Mandrekar, Valentina Jeliazkova, Donna Catalano, Gyongyi Szabo Apr 2010

Acute Alcohol Exposure Exerts Anti-Inflammatory Effects By Inhibiting Ikappab Kinase Activity And P65 Phosphorylation In Human Monocytes, Pranoti Mandrekar, Valentina Jeliazkova, Donna Catalano, Gyongyi Szabo

Gyongyi Szabo

Acute alcohol use is associated with impaired immune responses and decreased proinflammatory cytokine production. Our earlier studies have shown that acute alcohol intake inhibits NF-kappaB DNA binding in an IkappaBalpha-independent manner. We report using human peripheral blood monocytes and Chinese hamster ovary cells transfected with CD14 cells that acute alcohol treatment in vitro exerts NF-kappaB inhibition by disrupting phosphorylation of p65. Immunoprecipitation of p65 and IkappaBalpha revealed that acute alcohol exposure for 1 h decreased NF-kappaB-IkappaBalpha complexes in the cytoplasm. Phosphorylation of p65 at Ser(536) is mediated by IkappaB kinase (IKK)beta and is required for NF-kappaB-dependent cellular responses. We show …


Differential Tumor Necrosis Factor Production By Human Monocyte Subsets, Gyongyi Szabo, Carol Miller-Graziano, Jia-Yan Wu, Thomas Takayama, Karen Kodys Apr 2010

Differential Tumor Necrosis Factor Production By Human Monocyte Subsets, Gyongyi Szabo, Carol Miller-Graziano, Jia-Yan Wu, Thomas Takayama, Karen Kodys

Gyongyi Szabo

The human monocyte (M phi subset rosetting with anti RH-coated human erythrocytes via high-affinity, 72 kD receptors (FcRI+), contains the PGE2-producing immunosuppressive subpopulation, while the non-rosetting M phi subset (FcRI-) is the major plasminogen activator-producing and antigen-presenting M phi. This study gives additional evidence for the functional disparity of the FcRI- and FcRI+ M phi subsets. We are demonstrating that the normal human M phi subset isolated by rosetting via the FcRI receptor (FcRI+) produces greater quantities of tumor necrosis factor (TNF) than the non-rosetting (FcRI-) M phi. TNF production by the FcRI+ M phi subset is greater than that …


Tlr4, Ethanol, And Lipid Rafts: A New Mechanism Of Ethanol Action With Implications For Other Receptor-Mediated Effects, Gyongyi Szabo, Angela Dolganiuc, Qun Dai, Stephen Pruett Apr 2010

Tlr4, Ethanol, And Lipid Rafts: A New Mechanism Of Ethanol Action With Implications For Other Receptor-Mediated Effects, Gyongyi Szabo, Angela Dolganiuc, Qun Dai, Stephen Pruett

Gyongyi Szabo

Ethanol (EtOH) is the most widely abused substance in the United States, and it contributes to well-documented harmful (at high dosages) and beneficial (at low dosages) changes in inflammatory and immune responses. Lipid rafts have been implicated in the regulation and activation of several important receptor complexes in the immune system, including the TLR4 complex. Many questions remain about the precise mechanisms by which rafts regulate the assembly of these receptor complexes. Results summarized in this review indicate that EtOH acts by altering the LPS-induced redistribution of components of the TLR4 complex within the lipid raft and that this is …


Heme Oxygenase-1 Mediates The Anti-Inflammatory Effects Of Acute Alcohol On Il-10 Induction Involving P38 Mapk Activation In Monocytes, Yvonne Drechsler, Angela Dolganiuc, Oxana Norkina, Laszlo Romics, Weibo Li, Karen Kodys, Fritz Bach, Pranoti Mandrekar, Gyongyi Szabo Apr 2010

Heme Oxygenase-1 Mediates The Anti-Inflammatory Effects Of Acute Alcohol On Il-10 Induction Involving P38 Mapk Activation In Monocytes, Yvonne Drechsler, Angela Dolganiuc, Oxana Norkina, Laszlo Romics, Weibo Li, Karen Kodys, Fritz Bach, Pranoti Mandrekar, Gyongyi Szabo

Gyongyi Szabo

Inflammation and immunoregulatory cytokines play a central role in alcohol-induced liver damage. We previously reported that acute alcohol treatment augments IL-10 and inhibits TNF-alpha production in monocytes. Heme oxygenase-1 (HO-1), a stress-inducible protein, also regulates IL-10 and TNF-alpha production. Here, we report that augmentation of LPS-induced IL-10 production by alcohol was prevented by inhibition of HO-1 activity. Acute ethanol increased LPS-induced enzyme activity and RNA levels of HO-1, and DNA binding of AP-1, a transcription factor essential in HO-1 regulation. LPS-induced phospho-p38 MAPK levels were augmented by ethanol treatment and the p38 inhibitor, SB203580, prevented both the ethanol-induced increase in …


Selective Inhibition Of Antigen-Specific T Lymphocyte Proliferation By Acute Ethanol Exposure: The Role Of Impaired Monocyte Antigen Presentation Capacity And Mediator Production, Gyongyi Szabo, Bikash Verma, Donna Catalano Apr 2010

Selective Inhibition Of Antigen-Specific T Lymphocyte Proliferation By Acute Ethanol Exposure: The Role Of Impaired Monocyte Antigen Presentation Capacity And Mediator Production, Gyongyi Szabo, Bikash Verma, Donna Catalano

Gyongyi Szabo

Ethanol consumption is associated with impaired immunity. Our data demonstrate that even a single dose of a biologically relevant concentration (25-150 mM) of ethanol can down-regulate antigen-specific T lymphocyte proliferation. In contrast, ethanol augmented mitogen-induced T cell proliferation, suggesting that its inhibitory effect on antigen-specific T cell proliferation was due to its effects on monocytes (m phi s) rather than on T cells. The immunodepressive effects of ethanol on m phi antigen-presenting cell (APC) capacity were manifested whether alcohol treatment was limited to the antigen uptake-processing period only or was present during the entire period of antigen presentation. These inhibitory …


Acceptance Of An Abo-Incompatible Mismatched (Ab(+) To O(+)) Liver Allograft With The Use Of Daclizumab And Mycophenolate Mofetil, W. Fang, John Saltzman, Sarah Rososhansky, Gyongyi Szabo, Stephen Heard, Barbara Banner, Ravi Chari, Eliezer Katz Apr 2010

Acceptance Of An Abo-Incompatible Mismatched (Ab(+) To O(+)) Liver Allograft With The Use Of Daclizumab And Mycophenolate Mofetil, W. Fang, John Saltzman, Sarah Rososhansky, Gyongyi Szabo, Stephen Heard, Barbara Banner, Ravi Chari, Eliezer Katz

Gyongyi Szabo

Liver allograft survival rates of 50% to 60% are reported in blood group A, group B, group O (ABO)-incompatible mismatched grafts even when aggressive immunosuppressive protocols, including plasmapheresis, OKT(3), cyclophosphamide, cyclosporine, prostaglandin E(1), and steroids, are used. A 59-year-old woman, blood type O(+), required emergency retransplantation posttransplantation day 2 because of primary nonfunction of the liver allograft. A blood type AB(+) allograft was used. Induction immunosuppressive therapy included tacrolimus, mycophenolate mofetil, OKT(3) (muromonab-CD(3)), steroids, and prostaglandin E(1). In addition, plasmapheresis was performed daily for 9 days. OKT(3) and prostaglandin E(1) were also discontinued postoperative day 9. Biopsy-proven acute cellular rejection …


Inhibition Of Superantigen-Induced T Cell Proliferation And Monocyte Il-1 Beta, Tnf-Alpha, And Il-6 Production By Acute Ethanol Treatment, Gyongyi Szabo, Pranoti Mandrekar, Donna Catalano Apr 2010

Inhibition Of Superantigen-Induced T Cell Proliferation And Monocyte Il-1 Beta, Tnf-Alpha, And Il-6 Production By Acute Ethanol Treatment, Gyongyi Szabo, Pranoti Mandrekar, Donna Catalano

Gyongyi Szabo

Alcohol use has been shown to decrease monocyte antigen presentation capacity and inflammatory cytokine production, thereby increasing susceptibility to infections. Here, we demonstrate that in vitro acute treatment of normal monocytes with pharmacological doses of ethanol can decrease superantigen [Staphylococcus enterotoxins B (SEB) and A (SEA)]-induced T cell proliferation. Furthermore, ethanol treatment (25-100 mM) significantly inhibited SEA- or SEB-induced production of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and IL-6 in monocytes. Ethanol-induced down-regulation of monocyte TNF-alpha, IL-1 beta, and IL-6 occurred at both the protein and mRNA levels. Additional data suggest that ethanol can decrease IL-1 beta mRNA …


Hepatitis C And Innate Immunity: Recent Advances, Gyongyi Szabo, Angela Dolganiuc Apr 2010

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.


Tlr2- And Tlr4-Mediated Signals Determine Attenuation Or Augmentation Of Inflammation By Acute Alcohol In Monocytes, Shilpa Oak, Pranoti Mandrekar, Donna Catalano, Karen Kodys, Gyongyi Szabo Apr 2010

Tlr2- And Tlr4-Mediated Signals Determine Attenuation Or Augmentation Of Inflammation By Acute Alcohol In Monocytes, Shilpa Oak, Pranoti Mandrekar, Donna Catalano, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Most pathogens express ligands for multiple TLRs that share common downstream signaling. In this study, we investigated the effects of acute alcohol on inflammatory pathways induced by TLR2 or TLR4 ligands and their combination. In human monocytes, alcohol attenuated TLR4- but not TLR2-induced TNF-alpha protein and mRNA levels and NF-kappaB activation. In contrast, acute alcohol augmented TNF-alpha production when both TLR2 and TLR4 ligands were present. IL-1R-associated kinase (IRAK)-1 activity was reduced by alcohol in TLR4, but it was augmented in TLR2- plus TLR4-stimulated cells. IRAK-monocyte, an inhibitor of IRAK-1, was induced in TLR4, but it was reduced in TLR2- …


Inhibition Of Myeloid Dendritic Cell Accessory Cell Function And Induction Of T Cell Anergy By Alcohol Correlates With Decreased Il-12 Production, Pranoti Mandrekar, Donna Catalano, Angela Dolganiuc, Karen Kodys, Gyongyi Szabo Apr 2010

Inhibition Of Myeloid Dendritic Cell Accessory Cell Function And Induction Of T Cell Anergy By Alcohol Correlates With Decreased Il-12 Production, Pranoti Mandrekar, Donna Catalano, Angela Dolganiuc, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Alcohol consumption inhibits accessory cell function and Ag-specific T cell responses. Myeloid dendritic cells (DCs) coordinate innate immune responses and T cell activation. In this report, we found that in vivo moderate alcohol intake (0.8 g/kg of body weight) in normal volunteers inhibited DC allostimulatory capacity. Furthermore, in vitro alcohol treatment during DC differentiation significantly reduced allostimulatory activity in a MLR using naive CD4(+) T cells, and inhibited tetanus toxoid Ag presentation by DCs. Alcohol-treated DCs showed reduced IL-12, increased IL-10 production, and a decrease in expression of the costimulatory molecules CD80 and CD86. Addition of exogenous IL-12 and IL-2, …


Toll-Like Receptor 2 Mediates Inflammatory Cytokine Induction But Not Sensitization For Liver Injury By Propioni- Bacterium Acnes, Laszlo Romics, Angela Dolganiuc, Arumugam Velayudham, Karen Kodys, Pranoti Mandrekar, Douglas Golenbock, Evelyn Kurt-Jones, Gyongyi Szabo Apr 2010

Toll-Like Receptor 2 Mediates Inflammatory Cytokine Induction But Not Sensitization For Liver Injury By Propioni- Bacterium Acnes, Laszlo Romics, Angela Dolganiuc, Arumugam Velayudham, Karen Kodys, Pranoti Mandrekar, Douglas Golenbock, Evelyn Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

Recognition of Gram-positive bacteria by Toll-like receptor 2 (TLR2) induces activation of proinflammatory pathways. In mice, sensitization with the Gram-positive Propionibacterium acnes followed by a challenge with the TLR4 ligand, lipopolysaccharide (LPS), results in fulminant hepatic failure. Here, we investigated the role of TLR2 in liver sensitization to LPS-induced injury. Stimulation of Chinese hamster ovary cells and peritoneal macrophages with heat-killed P. acnes required expression of TLR2 but not of TLR4, suggesting that P. acnes was a TLR2 ligand. Cell activation by P. acnes was myeloid differentiation primary-response protein 88 (MyD88)-dependent, and it was augmented by coexpression of CD14 in …


Hepatitis C Virus Core And Nonstructural Protein 3 Proteins Induce Pro- And Anti-Inflammatory Cytokines And Inhibit Dendritic Cell Differentiation, Angela Dolganiuc, Karen Kodys, Andrea Kopasz, Christopher Marshall, Twan Do, Laszlo Romics, Pranoti Mandrekar, Maria Zapp, Gyongyi Szabo Apr 2010

Hepatitis C Virus Core And Nonstructural Protein 3 Proteins Induce Pro- And Anti-Inflammatory Cytokines And Inhibit Dendritic Cell Differentiation, Angela Dolganiuc, Karen Kodys, Andrea Kopasz, Christopher Marshall, Twan Do, Laszlo Romics, Pranoti Mandrekar, Maria Zapp, Gyongyi Szabo

Gyongyi Szabo

Antiviral immunity requires recognition of viral pathogens and activation of cytotoxic and Th cells by innate immune cells. In this study, we demonstrate that hepatitis C virus (HCV) core and nonstructural protein 3 (NS3), but not envelope 2 proteins (E2), activate monocytes and myeloid dendritic cells (DCs) and partially reproduce abnormalities found in chronic HCV infection. HCV core or NS3 (not E2) triggered inflammatory cytokine mRNA and TNF-alpha production in monocytes. Degradation of I-kappa B alpha suggested involvement of NF-kappa B activation. HCV core and NS3 induced production of the anti-inflammatory cytokine, IL-10. Both monocyte TNF-alpha and IL-10 levels were …


Emerging Role Of Micrornas In Liver Diseases, Shashi Bala, Miguel Marcos, Gyongyi Szabo Dec 2009

Emerging Role Of Micrornas In Liver Diseases, Shashi Bala, Miguel Marcos, Gyongyi Szabo

Gyongyi Szabo

MicroRNAs are a class of small non-coding RNAs that are found in plants, animals, and some viruses. They modulate the gene function at the post-transcriptional level and act as a fine tuner of various processes, such as development, proliferation, cell signaling, and apoptosis. They are associated with different types and stages of cancer. Recent studies have shown the involvement of microRNAs in liver diseases caused by various factors, such as Hepatitis C, Hepatitis B, metabolic disorders, and by drug abuse. This review highlights the role of microRNAs in liver diseases and their potential use as therapeutic molecules.


In Vitro And In Vivo Models Of Acute Alcohol Exposure, Angela Dolganiuc, Gyongyi Szabo Mar 2009

In Vitro And In Vivo Models Of Acute Alcohol Exposure, Angela Dolganiuc, Gyongyi Szabo

Gyongyi Szabo

Alcohol abuse is a global problem due to the financial burden on society and the healthcare system. While the harmful health effects of chronic alcohol abuse are well established, more recent data suggest that acute alcohol consumption also affects human wellbeing. Thus, there is a need for research models in order to fully understand the effect of acute alcohol abuse on different body systems and organs. The present manuscript summarizes the interdisciplinary advantages and disadvantages of currently available human and non-human models of acute alcohol abuse, and identifies their suitability for biomedical research.


Distinct Toll-Like Receptor Expression In Monocytes And T Cells In Chronic Hcv Infection, Angela Dolganiuc, Catherine Garcia, Karen Kodys, Gyongyi Szabo Mar 2006

Distinct Toll-Like Receptor Expression In Monocytes And T Cells In Chronic Hcv Infection, Angela Dolganiuc, Catherine Garcia, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

AIM: Hepatitis C virus often establishes chronic infections. Recent studies suggest that viral and bacterial infections are more common in HCV-infected patients compared to controls. Pathogens are recognized by Toll-like receptors (TLRs) to shape adaptive and innate immune responses.

METHODS: In this study, to assess the ability of HCV-infected host to recognize invading pathogens, we investigated Toll-like receptor expression in innate (monocytes) and adaptive (T cells) immune cells by real-time PCR.

RESULTS: We determined that RNA levels for TLRs 2, 6. 7, 8, 9 and 10 mRNA levels were upregulated in both monocytes and T cells in HCV-infected patients compared …