Computational prediction of highly conserved CD8+ and CD4+ T cell epitopes in bluetongue virus: A promising data for developing broad-spectrum bluetongue vaccine

Abstract

Abstract Bluetongue (BT) is an economically important arboviral disease of sheep, cattle, goats, and wild ruminants, particularly in America and Europe. However, it has remained uncontrolled due to the evolution of >32 serologically distinct BT virus (BTV) serotypes and the lack of broad-spectrum vaccines. While outer VP2 and VP5 proteins, involved in cell penetration, are less conserved, certain core BTV proteins NS1, NS2, NS3, and VP7 have higher amino acid conservancy. Here, using in silico epitope mapping and multiple sequence alignment, we analyzed all the antigenic BTV proteins for the presence of conserved T cell epitopes recognized by different mammals. We find that mouse Major Histocompatibility Complex-I (MHC-I) conserved epitopes are present in NS1, NS3, and VP7, and MHC-II-conserved epitopes in NS1, NS2, NS3, and VP7; and in bovines, Bovine Leukocyte antigen class-I and II-(BoLA-I & II)-conserved epitopes present in NS1, NS2, NS3, and VP7 proteins. The presence of these conserved epitopes from NS1, NS2, NS3, and VP7 proteins of BTV in the selected mammals, including bovine that is closely related to sheep, we believe they are also likely to be presented by MHCs of the primary natural host sheep. Thus, harnessing this knowledge in developing a pan-BTV vaccine would confer broad-spectrum protection against all the BTV serotypes in sheep and bovines. We are grateful for start-up funding by the Department of Microbiology and Immunology, Faculty of Medicine, Dalhousie University. PPCM wishes to acknowledge support from EU H20:20 grant ‘PALE-Blu’ (project number 727393-2).