gastro-congress-2016_posters-accepted-abstracts

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Volume 6, Issue 7(Suppl) J Gastrointest Dig Syst 2016
ISSN: 2161-069X JGDS, an open access journal
Page 58
Notes:
Gastro Congress 2016
October 24-25, 2016
conferenceseries.com
October 24-25, 2016 Valencia, Spain
9th Euro Global
Gastroenterology Conference
Hepatitis B Virus envelope variability of genotype A strains correlated with HBsAg persistence in
patients with acute or chronic hepatitis B and in HBV/HIV co-infected patients.
ESCHLIMANN Marine
Lorraine University, School of Medicine, Nancy, FRANCE
Around 240 million people are chronically infected by Hepatitis B virus (HBV) worlwide. The clearance of HBV surface
Antigen (HBsAg) correlated with a good clinical prognosis is rarely achieved, even on anti-HBV treatments. HBV
envelope proteins play a crucial role in virus cellular entry and in immune recognition. Our hypothesis is that the variability of
HBV envelope proteins could influence HBsAg clearance or persistence, as suggested in our previous study on HBV genotype
D (Velay et al., JVH, 2016). This study was extended to HBV genotype A infected patients with different clinical profiles: acute
(n=4) or chronic hepatitis B (n=6) and HBV/HIV coinfection under treatment (n=6). In each group, patients with HBsAg
clearance (Resolvers-R) were compared to Non-Resolvers (NR). For this purpose, HBV S and preS sequences were studied by
bulk genotyping and ultra-deep sequencing (UDS). Amino acid sequences were analized with bioinformatics for predicted
antigenicity. More frequent major mutations were observed in S gene than in preS region (p=0.02 in acute HBV infection).
Among mutations found exclusively in NR, nine were observed several times (W4stop, T173K/A in preS; R79H, T118A,
F134Y, Y161F, E164D, V209L in S). The mutation sY161F, found in four NR, leaded to a decrease in predicted antigenicity
(22.6%). In the pol gene overlapping the S gene, the number of mutations tended to be higher in treated than in untreated
patients (7.7 vs 3 mutations/patient). These results argue in favor of an influence of HBV envelope variability on the evolution
of Hepatitis B in various clinical contexts.
Biography
Marine ESCHLIMANN is a PhD student, currently the second year of her thesis. After a license in Cell Biology and Animal Physiology at the Faculty of Sciences,
Reims, France, she focused on Microbiology in the Master BioMANE at the Faculty of Sciences, Nancy, France. After a study on bacterial biofilms, she was
involved in a research program in Virology, in the University of Medicine, Nancy, France, with Pr E. Schvoerer et al. Thus she contributed to several investigations
on the variability of HBV envelope proteins with the support of a ministerial scholarship.
ESCHLIMANN Marine, J Gastrointest Dig Syst 2016, 6:7(Suppl)