Detection of B-Cell Epitopes of Hepatitis C Virus Envelope Proteins Associated with Viral Elimination

Objective: The aim of this study was to identify antibodies to peptides representing conserved Bcell epitopes of hepatitis C virus (HCV) envelope proteins E1 and E2, and to evaluate their significance for predicting viral elimination in patients undergoing directacting antiviral (DAA) therapy. Methods: Nine peptides derived from HCV envelope proteins E1 and E2 were synthesized using the solidphase method. Immunoreactivity of the peptides was assessed via a solidphase enzymelinked immunosorbent assay (ELISA) using serum samples from 9 patients with acute hepatitis C and 67 patients with chronic hepatitis C who received DAA therapy. Statistical significance was evaluated using pvalues. Results and Discussion: The presence of antibodies to the E1E2 complex before treatment, as demonstrated by other researchers, is associated with the achievement of a sustained virological response (SVR) in 70% to therapy with DAAs, and thus may serve as a predictive marker (p = 0.012). However, the possible predictive role of individual B-epitopes of HCV envelope proteins has not yet been clarified. The study revealed that the presence of antibodies to two peptides representing conserved immunodominant Bepitopes of the E2 protein was associated with achieving SVR in 73.0 and 89.2% of patients (p = 0.00001 and p = 0.0086, respectively). These findings suggest that antibodies targeting specific Bepitopes of HCV envelope proteins may serve as positive prognostic markers for treatment outcome. The results highlight the potential of using antibody profiles to improve prediction of therapy success, enable personalized treatment approaches, and inform vaccine development. Conclusions: The presence of antibodies to conserved immunodominant Bepitopes of the HCV E2 protein is a promising positive prognostic marker for achieving SVR in patients treated with DAAs. The obtained data can be used to improve methods for predicting therapy outcomes, develop personalized approaches to treatment, and develop vaccines against viral hepatitis C.