Xin Zhang,Xiangyu Guan,Qiuxia Wang,Xiao Wang,Xiaoke Yang,Shuwen Li,Xiao-Tian Zhao,Mengqi Yuan,Xingyou Liu,Hua-Ji Qiu ,Yongfeng Li

Viruses.2023 Dec 25;16(1):38.doi: 10.3390/v16010038.

Abstract

African swine fever (ASF) is a highly contagious disease caused by African swine fever virus (ASFV), affecting domestic and wild boars. The polyprotein pp220 of ASFV is responsible for producing the major structural proteins p150, p37, p14, p34, and p5 via proteolytic processing. The p34 protein is the main component of the ASFV core shell. However, the immunologic properties of the p34 protein  in vitro  and  in vivo  remain unclear. The results showed that the recombinant p34 protein expressed in prokaryotes and eukaryotes could react with convalescent swine sera to ASFV, suggesting that p34 is an immunogenic protein. Significantly, anti-p34 antibodies were found to inhibit the replication of ASFV in target cells. Furthermore, rabbits immunized with the recombinant C-strain of classical swine fever virus containing p34 produced both anti-p34 humoral and cellular immune responses. In addition, the p34 protein could induce a cell-mediated immune response, and a T-cell epitope on the p34 protein was identified using immunoinformatics and enzyme-linked immunospot (ELIspot) assay. Our study demonstrates that the p34 protein is a novel antigen of ASFV with protective potential.

Keywords: African swine fever virus; antigenicity; humoral and cellular immunity; p34 protein.