Zika viral proteome analysis reveals an epitope cluster within NS3 helicase as a potential vaccine candidate: an in silico study

Abstract

Zika virus (ZIKV), a mosquito-borne flavivirus, is now an emerging global public health concern. Currently, the pathogenicity, genetic diversity and the consequences of ZIKV infection are little known but a protective vaccine against ZIKV is an urgency. In this study, we have taken an immunoinformatics based approach to predict epitope cluster region in the whole proteome (3423 amino acids) of ZIKV. We have operated a range of bioinformatics algorithms to determine the epitopes of CD8+ cytotoxic T-cell (CTL), CD4+ helper T-cell (THL) and B cell. We have predicted an epitope cluster of 23 contiguous amino acids (region 1989-2011, WLEARMLLDNIYLQDGLIASLYR) residing on the protein NS3 helicase in ZIKV proteome. This epitope cluster contains fourteen CD4+ (THL) epitopes and six CD8+ (CTL) epitopes. The cluster region predicted to provide 93.86% population coverage worldwide. Finally, we have validated the epitopes by analysing their binding efficiency (binding energy within -4.7 to -6.9 kcal/mol) with specific HLA alleles. Based on our immunoinformatics analysis, we propose the peptide WLEARMLLDNIYLQDGLIASLYR as a new peptide vaccine candidate against Zika virus for further validation.