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Tacrolimus And Cyclosporine A Inhibit Allostimulatory Capacity And Cytokine Production Of Human Myeloid Dendritic Cells, Gyongyi Szabo, C. Gavala, Pranoti Mandrekar
Tacrolimus And Cyclosporine A Inhibit Allostimulatory Capacity And Cytokine Production Of Human Myeloid Dendritic Cells, Gyongyi Szabo, C. Gavala, Pranoti Mandrekar
Gyongyi Szabo
Myeloid dendritic cells (DCs) are pivotal in the recognition of alloantigens and, therefore, in the induction of allograft rejection. Induction of alloreactive T cell proliferation by myeloid DCs depends on the maturation of DCs, the expression of costimulatory molecules, and the cytokine environment. This study investigated the effects of tacrolimus and cyclosporine A (CsA) on DC maturation and allostimulatory capacity. Myeloid DCs were propagated from normal blood monocytes with interleukin (IL) 4 and GM-CSF for 7 days in the presence or absence of tacrolimus (FK506; 10 nM) or CsA (1 microg/mL). Exposure of DCs during maturation to tacrolimus or CsA …
Myeloid Dendritic Cells Of Patients With Chronic Hcv Infection Induce Proliferation Of Regulatory T Lymphocytes, Angela Dolganiuc, Edward Paek, Karen Kodys, Joanne Thomas, Gyongyi Szabo
Myeloid Dendritic Cells Of Patients With Chronic Hcv Infection Induce Proliferation Of Regulatory T Lymphocytes, Angela Dolganiuc, Edward Paek, Karen Kodys, Joanne Thomas, Gyongyi Szabo
Gyongyi Szabo
BACKGROUND and AIMS: Dendritic cells (DCs) initiate and sustain an efficient T-lymphocyte response. Chronic hepatitis C virus (HCV) infection is associated with inefficient T-cell functions that fail to eradicate the virus, so defects in DC function might be involved in HCV pathogenesis. This study analyzed the activities of myeloid DCs and distinct CD4(+) T-cell populations in samples collected from patients with HCV. METHODS: The abilities of primary BDCA1(+) or monocyte-derived DCs from HCV patients (HCV-DC) to stimulate CD4(+), CD4(+)CD25(-), or different ratios of CD4(+)CD25(+)/CD4(+)CD25(-) T cells were evaluated in mixed lymphocyte reactions. T-cell proliferation and phenotype were evaluated by flow …
Altered Innate Immunity In Chronic Hepatitis C Infection: Cause Or Effect, Gyongyi Szabo, Serena Chang, Angela Dolganiuc
Altered Innate Immunity In Chronic Hepatitis C Infection: Cause Or Effect, Gyongyi Szabo, Serena Chang, Angela Dolganiuc
Gyongyi Szabo
No abstract provided.
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.
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 …
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 …
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
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 …
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, …
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
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 …