BACKGROUND AND AIMS: Interferon-gamma (IFN-c) is a dimerized soluble cytokine which is critical to the defense against HCV infection as it can inhibit HCV replication in the replicon system. It has been proven that polymorphisms in some genes may influence the persistence of HCV infection, clinical outcome, HCV replication, and liver damage. METHODS: Family-based association designs offer a compromise between traditional linkage studies and case-control association studies. In these studies, association is assessed within families, and hence the confounding due to population heterogeneity can be eliminated. In our study 177 families have been recruited from The Upper, Middle, and Lower Egypt governments. These families include 323HCV patients as well as 347 non infected individuals. All were subjected to Routine clinical & laboratory investigations in addition to PCR HCV, HCV genotyping. Polymorphism of IFN-c (+874T/A, rs 62559044) was genotyped using ARM-PCR and confirmed using direct sequencing specific primers. RESULTS: Groups of our study were in Hardy-Weinberg equilibrium for IFN-c (+874T/A, rs 62559044). The T of IFN-c (+874T) allele was associated with 2 folds increased risk for HCV patients as compared to non-infected exposed person (OR = 1.9597, 95% CI 1.5269–2.5152, z statistic 5.284, p < 0.0001). The distribution of INF-c polymorphism was 10.81% AA, 51.39% AT &37.77% TT in HCV infected patients while in HCV-negative patients the distribution was 35.73% AA, 52.17% AT& 12.1%TT CONCLUSIONS: The T allele of rs 62559044 SNP of +IFNc gene polymorphism may have a crucial role of susceptibility to HCV infection in Egyptian families. This research was funded by Science & Technology Development Foundation (STDF), Project NO.1784 (TC/2/ Health/2009/hep-1.3).

have previously generated a murine tropic HCV (mtHCV) strain harboring three mutations within the viral envelope proteins allowing productive entry into mouse cell lines. In this study we aimed to characterize the ability of mtHCV to enter and infect mouse hepatocytes in vivo and in vitro. Using a highly sensitive, Cre-activatable we demonstrate that mtJc1 also can enter mouse hepatocytes in vivo in the absence of any human cofactors. Viral entry was more efficient when mouse CD81 and OCLN were overexpressed and was still relying on expression of mouse CD81 and SCARB1. To validate viral uptake specificity and to establish a host environment that may be more conducive to viral replication we utilized a number of mouse mutant strains with targeted disruptions in genes involved in HCV entry or antiviral innate immune defenses, respectively. In addition, we are in the process of testing directly the impact of host genetics HCV persistence utilizing different inbred mouse strains. Using human liver chimeric mice we show that the gain of function mutations of mtHCV are stably maintained over time. We observed transient replication of mtHCV in STAT1 deficient mice and highly immunocompromized mice engrafted with allogeneic STAT1-/hepatocytes. These results establish proof-of-concept that the barriers limiting HCV species tropism can be overcome by viral adaptation. Additional viral adaptations are likely needed to increase the robustness of a murine model system for hepatitis C.

Background: Immungenetic data suggest that lambda-IFNs (l-IFN) may modulate anti-HCV activity of natural killer (NK) cells. However, NK cells do not express the IFN-lambda receptor 1 (IFN-lR1). Thus, we studied the hypothesis that l-IFNs act on other leucocyte subsets, which then indirectly modulate NK cell activity.

POSTERSare associated with antiviral effector T-cell dysfunction, which influences on T-cell exhaustion and persistent viral infection.These PD-1 and CTLA-4 are up-regulated in chronic viral infection such as chronic hepatitis C, chronic hepatitis B and human immunodeficiency virus infection but there is no report about the role of PD-1 and CTLA-4 in patients with symptomatic acute hepatitis A. We investigated the expression of PD-1 and CTLA-4 during symptomatic and convalescent phases of acute hepatitis A. Methods: Seven patients with symptomatic acute hepatitis A, 5 patients with non-viral acute toxic hepatitis were enrolled for detection of PD-1 and CTLA-4 on T-cell subset of peripheral blood mononuclear cells (PBMC) isolated from these subjects during symptomatic and convalescent phases by flow cytometry.Five as healthy control were also examined for comparison with these patients.Results: Symptomatic acute hepatitis A showed significant increase of PD-1 and CTLA-4 expression compared to non-viral acute toxic hepatitis or healthy control (PD-1; 18.3±15.7%vs. 3.7±3.0%vs. 1.6±1.8%,p < 0.05, CTLA-4; 23.5±12.0%vs. 6.1±1.2% vs. 5.9±1.2%,p < 0.05) (median ± SD).In addition, highly expressed PD-1 and CTLA-4 were dramatically decreased in convalescent phase of acute hepatitis A. Conclusions: In acute hepatitis A, PD-1 and CTLA-4 are upregulated during symptomatic phase then down-regulated after recovery.This changing pattern of PD-1 and CTLA-4 expression was not seen in non-viral acute toxic hepatitis.Our findings suggest that PD-1 and CTLA-4 have protective effect as inhibitory molecules to suppress cytotoxic T-cells which induce destruction of viral infected hepatocytes.

Figure 1.A reduction of circulating CD3 + lymphocytes in patients with HBV-ACLF.A. The absolute CD3 + T lymphocyte count, including CD3 + CD4 + and CD3 + CD8 + T cells (B) in peripheral blood from 3 groups was measured by flow cytometry.The line and error bars represent the median with interquartile range (A, for at least one group data were in skewed distribution) or mean with SEM (B, for all data displayed normal distribution), and the same method with following figures.Statistical comparisons were performed by ANOVA or the non-parametric Nemenyi test.*p < 0.05; **p < 0.01; and not significant (NS), p > 0.05.In comparison with controls, the CD4 + Tregs count remained unchanged while the Tconv count correspondingly declined, promoting elevation of the Tregs-to-Tconv ratio amongst CD4 + T cells in HBV-ACLF patients.Moreover, the number of circulating IL-17-producing CD4 + Th17 cells decreased slightly and the CD4 + Treg-to-Th17 ratio increased.Further, we showed that the frequency of activated Treg-II (CD4 + CD25 +++ CD45RA -) subpopulation was elevated and the ratio of Treg II/I was dramatically higher in HBV-ACLF patients than controls.Conclusions: The development of CD4 + Tregs, in particular the activated Treg II subpopulation with potent suppressive properties, prevails over Tconv, while an exhaustion of circulating CD3 + T lymphocytes exists in HBV-ACLF patients, which probably contribute to immune dysfunction status of HBV-ACLF.

Introduction:Progressive hepatic fibrosis is a common feature of chronic hepatitis C. Natural Killer (NK) cells represent a major component of intra-hepatic lymphocytes and have been shown to be important for the early control and natural course of HCV infection.Moreover, in mouse models it has been shown that natural killer cells can attenuate liver fibrosis via killing of activated hepatic stellate cells (HSC) in a NKG2D and TRAIL dependent manner.Here, we analyzed the interactions of human NK cells from HCVpositive patients with activated primary HSC and the potential effects of interferon-a (IFN-a) treatment.Material and methods: NK cells from untreated HCV-RNA(+) patients (n = 11), interferon-a (IFN-a) treated patients (n = 10) and healthy controls (n = 12) were co-incubated with activated primary HSC (ScienCell).NK cells from healthy persons were incubated in the presence or absence of IFN-a (25 IU/ml).Cytotoxic activity of NK cells was studied using the CD107a assay.In addition, INF-g and TNFa production of NK cells was measured by FACS analysis.Induction of HSC apoptosis (active Caspase-3) was analyzed flowcytometrically.Results: Analyzing cytolytic activity of NK cells following coincubation with HSC only discrete CD107a expression could be observed on both NK cells from HCV(+) patients and healthy controls ([mean±SEM: 5.7±0.7% vs. 4.7±0.8%;p = n.s.).Furthermore, only negligible secretion of IFN-g and TNF-a could be observed.However, NK cells from untreated HCV-infected patients were significantly more effective in induction of HSC apoptosis (20.8±2.1%)than NK cells from healthy controls (6.2±0.6%).Of note, NK cells from IFN-a/RBV treated HCV(+) patients displayed an even stronger capability to kill HSC (26.9±4.3%).In vitro stimulation of NK cells with IFN-a resulted in a significant up-regulation of TRAIL and was associated with increased killing of HSC as compared to un-stimulated NK cells.This effect could be blocked with both NKG2D-and TRAIL-specific antibodies.Conclusion: NK cells from HCV-infected patients are highly efficient in inducing apoptosis of activated hepatic stellate cells.This function of NK cell is increased following IFN-a treatment.Thus, NK cells may play an important anti-fibrotic role in chronic hepatitis C.

Background:The factors affecting response to HCV-specific therapy are only partly understood at the moment.However, three recent reports demonstrated a genetic polymorphism near the IL28B gene, encoding interferon-l-3, to be strongly associated with response to treatment with pegylated interferon-a and ribavirin in HCV mono-infected patients.Since co-infection with the hepatitis C virus (HCV) constitutes a major health problem worldwide in HIVpositive patients, we studied whether the IL28B gene polymorphism (rs12979860) also affects treatment outcomes in HCV/HIV coinfected patients.Methods: IL28B genotypes were determined in 192 HCV/HIV coinfected patients treated with pegylated interferon-a, including 74 patients with acute and 118 with chronic hepatitis C. Rates of sustained virological responses (SVR) were compared in patients carrying different genotypes.As a control, 137 healthy and 199 HCV mono-infected subjects were studied.Results: IL28B genotype distribution did not differ significantly between HIV-positive patients with acute versus chronic HCV coinfection and the two other study groups.In HIV/HCV co-infection carriers of C/C genotype had significantly lower HIV loads than patients with other genotypes (41 ×10 3 copies/ml [0.11-341]) vs. 95.9×10 3 copies/ml [0.12-1371], p = 0.038 C/C versus C/T and T/T).However, this difference must be attributed exclusively to HIV-positive patients with chronic hepatitis C (p = 0.011).Unlike HIV serum levels, HCV loads were significantly higher in carriers of the C/C genotype (12.1×10 6 IU/ml [<0.1-124] vs. 4.8×10 6 IU/ml [<0.1-46]; p = 0.0026).Of note, HCV/HIV patients with the homozygous C/C genotype had significantly higher SVR rates than patients with other genotypes (C/T and T/T combined) (58.2% vs. 40.6%;OR 1.6; p = 0.04).However, this effect reached statistical significance only in the HIV-positive subgroup of patients with chronic hepatitis C (50% versus 29%; P = 0.02; OR 2.4) but not in the subgroup with acute hepatitis C (71.4% versus 59%; n.s.). Conclusion:The IL28B genetic polymorphism has only limited effect on treatment-induced clearance of hepatitis C virus in HCV/HIV co-infected patients.This is in strong contrast to observations in HCV mono-infected patients and may suggest interference of HIV with the interferon-l signaling pathways.

The most notable changes occurred mainly in interferon-stimulated genes.Treatment response could be predicted with a molecular gene signature.The genes included in the signature encode molecules secreted in the serum and provide a logical functional approach for the development of serum markers to predict response to treatment.

Introduction: Dys-regulated function of natural killer (NK) cells has been proposed as a mechanism contributing to viral persistence in hepatitis C virus (HCV) infection and HCV-associated liver damage.Recent data indicate that members of the signaling lymphocytic activating molecule (SLAM) family receptors (i.e.NTB-A, CRACC, and 2B4) and their respective ligands NTB-A, CRACC, and CD48 have important functions in NK cell biology.However, in hepatitis C expression of these molecules has not been studied in great detail.Methods: NK cells from 54 patients with chronic hepatitis C, 26 subjects who had achieved a sustained virological response after after antiviral therapy (n = 26), and 47 healthy individuals were analysed by flow cytometry.Results: Expression of 2B4 and NTBA was not altered in HCV infection.However, expression of CRACC was significantly downregulated on CD56 bright NK cells in chronic hepatitis C (mean fluorescence index; HCV vs. healthy controls: 7.3 vs. 8.8, p < 0.01).In contrast to CRACC, expression of the ligand CD48 was significantly higher in the NK cell subsets from HCV-positive patients than in healthy controls (CD56 dim : 32.92 vs. 26.37,p = 0.02; CD56 bright : 12.79 vs. 9.6, p < 0.01).Interestingly, expression of CD48 on CD56 dim NK cells correlated positively with elevated aminotransferase levels (ALT: p = 0.02; AST: p < 0.01).Successful anti-viral treatment was associated with normalization of CD48 levels.Conclusions: This study demonstrates altered expression of the SLAM receptor CRACC and CD48 on NK cells in chronic hepatitis C.This phenotype may contribute to dys-regulated function of NK cells in HCV infections.