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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 …
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 …
Antigen Presentation By The Cd4 Positive Monocyte Subset, Gyongyi Szabo, Carol Miller-Graziano, Karen Kodys
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 …
Differential Tumor Necrosis Factor Production By Human Monocyte Subsets, Gyongyi Szabo, Carol Miller-Graziano, Jia-Yan Wu, Thomas Takayama, Karen Kodys
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 …
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
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 …
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
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, …