Significance of antibody detection to individual B-epitopes of envelope proteins of hepatitis C virus

Abstract

Hepatitis C virus (HCV) is hepatotropic viruses, causing chronic infection, which can lead to liver failure, cirrhosis, and hepatocellular carcinoma. The two viral envelope glycoproteins E1 and E2 mediate the virus entry into host cells, and they are the targets of virus-n eutralizing antibodies, which play an important role in limiting infection. The aim of the study was to analyze infected human antibody response to peptides reproducing B-cell epitopes of HCV envelope proteins to assess their possible association with virus elimination. The synthesis of three peptides from envelope proteins was carried out by the solid phase method. The immunoreactivity of the peptides was studied with blood sera from 63 participants with viral hepatitis C. The amino acid sequences of the peptides corresponded to region 244–259 and 313–324 of the E1 protein and 395–411 of the E2 protein. Peptide immunoreactivity was assessed by enzyme-linked immunosorbent assay (ELISA) using blood sera of 63 participants with acute and chronic hepatitis C. According to the results of ELISA, it was found that antibodies were detected in 55,6% (sampling error 6,3%) of participants. If the presence of an antibody titer was 1:80 or higher to the analyzed peptides, then the most participants completed therapy with a sustained virological response or acute hepatitis with the virus elimination. That may indicate the potential significance of the presence of antibodies to B-cell epitopes of HCV envelope proteins in this titer of high for a positive outcome of acute hepatitis C and therapy with direct antiviral drugs.