Variant analysis and immunogenicity prediction of envelope gene of HCV strains from China

The putative envelope protein E2 of hepatitis C virus (HCV) is the most variable antigenic fragment in the whole viral genome and is responsible mainly for the large inter- and intra-individual heterogeneity of the infecting virus. To analyze variation and immunogenicity of HCV envelope genes of HCV strains from China, the serum samples from 12 Chinese patients with chronic hepatitis C from 10 cities of China were amplified, sequenced directly, and compared with international strains reported previously. Variant analysis and immunogenicity prediction were then carried out with computer programs. The results suggested that HCV envelope genes show diversity in the north and the south of China and that they vary among different genotypes. Therefore, the diversity among different genotypes and derived areas should be calculated for HCV vaccine design; simultaneously, domains characterized by the hydrophilicity and the conserved immunogenicity could be targeted, for example, the domain of aa434-444, aa408-414, aa449-462 in the envelope region and aa399-406 in HVR1. These data may hold the key for future development of HCV vaccine in China.