Computational Analysis for Prediction of Multi Epitopes Vaccine against Blue Tongue Virus Serotype 4 from VP5 and VP7 Proteins

Abstract

Blue Tongue Disease (BTD) is a non-contagious insect transmitted disease of ruminants caused by double stranded RNA virus. This study aimed to predict an effective multi-epitopes vaccine against BTD from VP5 and VP7 as immunogenic proteins using immunoinformatic tools. The VP5 and VP7 proteins sequences were retrieved from GenBank of National Center for Biotechnology Information (NCBI). The sequences of each protein were aligned for conservancy using Bioedit software. Immune Epitope Database (IEDB) analysis resources were used to predict B and T cell epitopes. The proposed MHC-1 epitopes of both proteins were further subjected to molecular docking to show minimum binding energy of each epitopes. In our results, two epitopes (235-SEEV-235 and 85-PDPLSP-90) from VP5 and two epitopes (79-PISPDYTQ-86 and 297-PIFPPN-302) from VP7 were proposed as B cell epitopes since they were shown to be linear, surface accessible and antigenic epitopes. For T cells, MHC-1 binding prediction tools showed multiple epitopes strongly interacted with BoLA alleles from both VP5 and VP7. Among them three epitopes, (257-KLKKVINAL-265, 487-QMHILRGPL-495 and 350-VMMRFKIPR-358) fromVP5 protein and four epitopes (86-QHMATIGVL-94, 315-TLADVYTVL-323, 17-TLQEARIVL-25 and 10-TVMRACATL-18) from VP7 protein interacted with the highest number of alleles and demonstrated best binding affinity to MHC-1 alleles. Thus were proposed as a vaccine candidate from VP5 and VP7 proteins. All the epitopes from VP5 and VP7 that interacted with MHC-1 alleles when subjected to molecular docking against the sheep b_microglobulin alleles demonstrated biologically significant higher binding affinity which expressed by their lower global and attractive energy. In conclusion, eleven epitopes were predicted as promising vaccine candidates against BTD from the VP5 and VP7 immunogenic proteins. These epitopes require to be validated experimentally through in vitro and in vivo studies.