Identification of Novel Multi Epitopes Vaccine against the Capsid Protein ( ORF2 ) of Hepatitis E Virus

Abstract

Hepatitis E virus (HEV) is non-enveloped, small virus with a positive RNA sense in the family Hepeviredae genus Orthohepevirus. More than 20 million individuals annually infected by HEV with increased mortality rate ranged from 8% to 20% in pregnant women. The aim of the present study was to design multi peptides vaccine against HEV using immunoinformatic tools that elicited humoral and cellular immunity. The capsid protein sequences of HEV were retrieved from NCBI and subjected to various immunoinformatics tools from IEDB to assess their conservancy, surface accessibility and antigenicity as promising epitopes against B cells. Moreover the binding affinity of the conserved predicted epitopes was analyzed against MHC-I and MHC-II alleles of the T cells. The predicted epitopes were further assessed for their population coverage. For B-cell 32, 23 and 12 epitopes were predicted as linear conserved epitopes, surface accessibility and antigenic respectively. However the best B cell epitopes that overlapped the prediction tools were 165PLQD168, 219PTSVD223, 452PTPSPAPS459, 556GYPYNY561 and 615DYPA619. For T cell, the MHC-I alleles interacted with 37 conserve epitopes. Four epitopes (367GIALTLFNL375, 379LLGGLPTEL387, 389SSAGGQLFY397 and 394QLFYSRPVV402) interacted with MHC class-I with high affinity and specificity and hence were proposed as vaccine candidates. Moreover seven epitopes out of 125 predicted epitopes (were 205YAISISFWP213, 299LLDFALELE307, 341LTTTAATRF349, 367GIALTLFNL375, 368IALTLFNLA376, 379LLGGLPTEL387 and 394QLFYSRPVV402) were proposed as vaccine since they demonstrated high affinity to MHC-II alleles. The epitopes 367GIALTLFNL375, 379LLGGLPTEL387 and 394QLFYSRPVV402 were recognized interacting with both MHC-I and MHC-II alleles. The population coverage epitopes set for MHC-I and MHC-II alleles was 78.97% and 99.99%, respectively. While the epitopes set for all T cell proposed epitopes was 100%. Thirteen epitopes were predicted eliciting B and T cells and proposed as vaccine candidates against HEV. However these proposed epitopes require clinical trials studies to ensure their efficacy as vaccine candidates.