Screening and identification of linear B-cell epitopes on structural proteins of African Swine Fever Virus

This study aims to screen and identify linear B-cell epitopes on the structural proteins of African Swine Fever Virus (ASFV) to assist in the development of peptide-based vaccines. In experiments, 66 peptides of 12 structural proteins of ASFV were predicted as potential linear B-cell epitopes using bioinformatics tools and were designed; the potential epitope proteins carried the GST tag were expressed, purified, and subjected to antigenicity analysis with porcine antiserum against ASFV, and further identified based on their immunogenicity in mice. A total of 22 potential linear B-cell epitopes showed immunoreactivity and immunogenicity. Of these epitopes, 13 epitopes were firstly identified including 4 epitopes located in p72 (352–363, 416–434, 424–439, 496–530 aa), 3 epitopes located in pE248R (121–136, 138–169, 158–185 aa), and only one epitope of each protein of pH108R (33–46 aa), p17 (63–86 aa), pE120R (65–117 aa), pE199L (175–189 aa), p12 (36–56 aa) as well as pB438L (211–230 aa). Notably, the immunoreactivity of the epitopes from the 63-86 aa of p17 and the 65–117 aa of pE120R were the highest amongst identified epitopes, while the immunogenicity of epitopes from the 36–56 aa of p12, the 211–230 aa of pB438L, the 352–363 aa of p72 and the 63–86 aa of p17 were the best strong. The other 9 epitopes are partly overlapped with previous researches. These epitopes identified here will further enrich the database of ASFV epitope, as well as help to develop safe, effective epitope-based ASF vaccines and ASF diagnostic reagents.