- Email: [email protected]
784 CELL ENTRY FACTOR USAGE AND VIRAL EVASION IN HEPATITIS C VIRUS INFECTION IN VIVO
POSTERS independent groups of patients. Mir-224_1 has been described upregulated in hepato-cellular carcinomas. Moreover, deregulation of miR-217 has been reported in pancreatic cancers. Mir-23a inhibits both the development of B cells and the production of IL-6. Interestingly, in our study mir-122 is slightly up-regulated in NRs compared to SVRs. The levels of expression of miRNAs involved in tumoral processes were higher in the liver of NRs than in SVRs and RRs. Conclusion: NRs and SVRs present different miRNAs hepatic expression, before treatment. In particular, mir-99a, mir-181a-2*, mir-23a and mir-217 were significantly deregulated in NRs compared to SVRs. Thus, treatment response could be predicted with a molecular miRNAs signature. 783 DIFFERENTIAL LIVER MIRNAS EXPRESSION IN CHRONIC HEPATITIS C PATIENTS AT EARLY STAGES OF LIVER FIBROSIS 3 E. Estrabaud1,2 , I. Bieche ` , M. Lapalus1,2 , S. De Muynck1,2 , O. Lada1,2 , M. Martinot-Peignoux1,2 , A. Duces3 , D. Valla1 , P. Bedossa4 , P. Marcellin1,2 , M. Vidaud3 , T. Asselah1,2 . 1 Service d’H´epatologie, Pˆ ole des Maladies de l’Appareil Digestif, Hˆ opital Beaujon, Clichy, 2 CRB3-INSERM U773, Hˆ opital Bichat, Paris, 3 Service de Biochimie et G´en´etique Mol´eculaire, Hˆ opital Beaujon, 4 Service d’Anatomie Pathologique, Clichy, France E-mail: [email protected] Background and Aims: In chronic Hepatitis C (CHC), the stage of fibrosis is correlated with the risk of development of cirrhosis and hepatocellular carcinoma. Although some circulating markers can help to distinguish high from low fibrosis score, analysis of the liver biopsy remains the only way to differentiate mild (F1) and moderate (F2) fibrosis. Since the identification of RNA silencing, miRNAs have been implicated in the regulation of many cellular pathway. The aim of this study was to identify a liver miRNA signature, in patients with CHC, associated to the different stages of fibrosis and in particular F1 and F2. Methods: Liver biopsies from 111 untreated CHC patients were studied. Male gender represents 67% of the patients, the mean age was 47.1±8.9 and the BMI was 25.38±4.1 kg/m2 . Before treatment, the mean viral load was 2.97×106 copies/ml and the ALT mean was 105.1±72.5. Among these patients, 34 presented a Metavir score F1, 40 F2, 18 F3 and 17 F4. Patients were mainly infected with genotype 1 and 4 (68% and 14.5%). Real-time quantitative RT-PCR assays were performed to analyse the expression of 851 human miRNAs. Results: The cellular miRNAs expression profiles are significantly different in patients with low (F1) and high (F2–F4) fibrosis score. Differential expression of some miRNAs was observed in moderate fibrosis (F2) in comparison with mild fibrosis (F1). In particular, mir363 and mir-451 present significantly higher expression in F1 than in F2 patients while mir-219 and 224 expressions are upregulated in F2 compared to F1. Interestingly, mir-224 expression is correlated to the fibrosis score. These specific miRNAs deregulated in F1 and F2 were reported to be associated in the development of diseases. Indeed, miR-363 is deregulated in rheumatoid arthritis, mir-451 acts as a tumor suppressor in glioma cells and mir-224 is upregulated in many cancers. Conclusion: Patients with metavir score F1 and F2 present different miRNAs hepatic expression. In particular, the miRNAs mir-363, mir451, mir-219 and mir-224 were significantly deregulated in patients with Fibrosis score F1 and F2. Thus, miRNAs profile expression could help to identify the liver fibrosis score.
784 CELL ENTRY FACTOR USAGE AND VIRAL EVASION IN HEPATITIS C VIRUS INFECTION IN VIVO P. Carolla1,2 , I. Fofana1,2 , S. Fafi-Kremer1,2,3 , M.N. Zahid1,2 , K. Cury1,2 , M. Turek1,2 , M. Bastien-Valle1,2 , F.-L. Cosset4 , T. Pietschmann5 , J. Hayer6 , C. Combet6 , F. Habersetzer7 , M. Doffoel ¨ 7 , Z.-Y. Keck8 , S.K.H. Foung8 , M.B. Zeisel1,2 , F. Stoll-Keller1,2,3 , T.F. Baumert1,2,7 . 1 Inserm, U748, Strasbourg, 2 Universit´e de Strasbourg, France; 3 Laboratoire de Virologie, Hˆ opitaux Universitaires de Strasbourg, Strasbourg, 4 Inserm, U758, ENS Lyon, Lyon, France; 5 Division of Experimental Virology, TWINCORE, Hannover, Germany; 6 Institut de Biologie et Chimie des Prot´eines, UMR 5056, CNRS, Universit´e de Lyon, Lyon, 7 Pˆ ole H´epato-Digestif, Hˆ opitaux Universitaires de Strasbourg, Strasbourg, France; 8 Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA E-mail: samira.fafi[email protected] Hepatitis C virus (HCV) entry is the first step of viral infection and a key target of host neutralizing responses. Enhanced viral entry and escape from host neutralizing responses have been shown allow the virus to persistently infect the liver during transplantation. Using acute liver graft infection as an in vivo model we investigated the molecular mechanisms of viral evasion. Reverse genetics identified two positions in HCV envelope glycoprotein E2 mediating enhanced cell entry by modulating host receptor usage. Simultaneously, altered cell receptor usage conferred resistance to neutralization of antibodies. Kinetic studies demonstrate that the identified evasion factors are part of a conformational neutralizing epitope modulating E2-CD81 interactions at an entry step occurring post particle binding. Functional studies using a large panel of patient-derived antibodies demonstrate the functional impact of this mechanism for viral persistence in acute graft infection as well as chronic infection in general. In conclusion, our findings identify a novel and clinically important mechanism of viral evasion, where co-evolution simultaneously occurs between cellular entry factor usage and escape from neutralization. The identification of this mechanism advances our understanding of viral evasion and paves the way for the development of novel antiviral strategies targeting envelope-host entry factor interactions. P.C. and I.F. contributed equally to this work. 785 OXIDATIVE DNA DAMAGE IN PATIENTS WITH CHRONIC HCV-RELATED LIVER DISEASES: PROTECTIVE EFFECT OF COFFEE CONSUMPTION R. Cardin1 , M. Piciocchi1 , D. Martines1 , L. Scribano1 , A. Floreani1 , M. Petracco2 , F. Farinati1 . 1 Department of Surgical and Gastroenterological Sciences, Padua University, Padua, 2 Institute of Scientific Information on Coffee (ISIC), Trieste, Italy E-mail: [email protected] Introduction: In patients with chronic liver damage, particularly when HCV-related, coffee intake is associated with a reduced risk of disease progression and of hepatocellular carcinoma (HCC) development. Aim: To investigate the mechanisms underlying the protective effect of coffee with respect to cirrhosis and HCC, evaluating the changes in time of oxidative DNA adducts formation and of liver damage, fibrosis and viral load during coffee consumption. Patients and Methods: Forty patients with HCV-related chronic liver disease were recruited and, after informed consent, randomized into two groups: the first group consumed 4 cups of coffee per day for 1 month, while the second group remained coffee “abstinent” for the same period. At day 30, the two patients’ groups were switched over. At t0 (before entering the study), during coffee intake and during abstinence, the following parameters were evaluated: liver function tests [AST, ALT, GGT and ALP], viral load [HCV-RNA], oxidative DNA damage [8-hydroxydeoxyguanosine (8-
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784 CELL ENTRY FACTOR USAGE AND VIRAL EVASION IN HEPATITIS C VIRUS INFECTION IN VIVO P. Carolla1,2 , I. Fofana1,2 , S. Fafi-Kremer1,2,3 , M.N. Zahid1,2 , K. Cury1,2 , M. Turek1,2 , M. Bastien-Valle1,2 , F.-L. Cosset4 , T. Pietschmann5 , J. Hayer6 , C. Combet6 , F. Habersetzer7 , M. Doffoel ¨ 7 , Z.-Y. Keck8 , S.K.H. Foung8 , M.B. Zeisel1,2 , F. Stoll-Keller1,2,3 , T.F. Baumert1,2,7 . 1 Inserm, U748, Strasbourg, 2 Universit´e de Strasbourg, France; 3 Laboratoire de Virologie, Hˆ opitaux Universitaires de Strasbourg, Strasbourg, 4 Inserm, U758, ENS Lyon, Lyon, France; 5 Division of Experimental Virology, TWINCORE, Hannover, Germany; 6 Institut de Biologie et Chimie des Prot´eines, UMR 5056, CNRS, Universit´e de Lyon, Lyon, 7 Pˆ ole H´epato-Digestif, Hˆ opitaux Universitaires de Strasbourg, Strasbourg, France; 8 Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA E-mail: samira.fafi[email protected] Hepatitis C virus (HCV) entry is the first step of viral infection and a key target of host neutralizing responses. Enhanced viral entry and escape from host neutralizing responses have been shown allow the virus to persistently infect the liver during transplantation. Using acute liver graft infection as an in vivo model we investigated the molecular mechanisms of viral evasion. Reverse genetics identified two positions in HCV envelope glycoprotein E2 mediating enhanced cell entry by modulating host receptor usage. Simultaneously, altered cell receptor usage conferred resistance to neutralization of antibodies. Kinetic studies demonstrate that the identified evasion factors are part of a conformational neutralizing epitope modulating E2-CD81 interactions at an entry step occurring post particle binding. Functional studies using a large panel of patient-derived antibodies demonstrate the functional impact of this mechanism for viral persistence in acute graft infection as well as chronic infection in general. In conclusion, our findings identify a novel and clinically important mechanism of viral evasion, where co-evolution simultaneously occurs between cellular entry factor usage and escape from neutralization. The identification of this mechanism advances our understanding of viral evasion and paves the way for the development of novel antiviral strategies targeting envelope-host entry factor interactions. P.C. and I.F. contributed equally to this work. 785 OXIDATIVE DNA DAMAGE IN PATIENTS WITH CHRONIC HCV-RELATED LIVER DISEASES: PROTECTIVE EFFECT OF COFFEE CONSUMPTION R. Cardin1 , M. Piciocchi1 , D. Martines1 , L. Scribano1 , A. Floreani1 , M. Petracco2 , F. Farinati1 . 1 Department of Surgical and Gastroenterological Sciences, Padua University, Padua, 2 Institute of Scientific Information on Coffee (ISIC), Trieste, Italy E-mail: [email protected] Introduction: In patients with chronic liver damage, particularly when HCV-related, coffee intake is associated with a reduced risk of disease progression and of hepatocellular carcinoma (HCC) development. Aim: To investigate the mechanisms underlying the protective effect of coffee with respect to cirrhosis and HCC, evaluating the changes in time of oxidative DNA adducts formation and of liver damage, fibrosis and viral load during coffee consumption. Patients and Methods: Forty patients with HCV-related chronic liver disease were recruited and, after informed consent, randomized into two groups: the first group consumed 4 cups of coffee per day for 1 month, while the second group remained coffee “abstinent” for the same period. At day 30, the two patients’ groups were switched over. At t0 (before entering the study), during coffee intake and during abstinence, the following parameters were evaluated: liver function tests [AST, ALT, GGT and ALP], viral load [HCV-RNA], oxidative DNA damage [8-hydroxydeoxyguanosine (8-
Journal of Hepatology 2011 vol. 54 | S209–S361
S315