Simple Summary
African swine fever is a highly contagious disease that affects domestic pigs and wild boars. Despite the serious effects on the pig industry worldwide, there are no currently available effective vaccines. Therefore, understanding this pathogen is necessary for the control and prevention of African swine fever. The pathogenic virus expresses more than 150 viral proteins, with the p54 protein located on the inner envelope and an important structural protein. Here, we developed three monoclonal antibodies specific for the p54 protein, and identified three precise antigenic epitopes recognized by these monoclonal antibodies. A comparison with the p54 sequences of different viral strains revealed that some of these antigenic epitopes are highly conserved in genotype I and II strains. Moreover, the anti-genic epitopes can be used for immune detection of specific viral antibodies. Thus, our work provides new insights into the virus’s antigenicity and offers an alternative tool for the diagnosis of African swine fever infection.
Abstract
African swine fever (ASF) is caused by the African swine fever virus (ASFV); infection in domestic pigs and wild boars leads to a highly contagious, hemorrhagic disease. The p54 protein is encoded by the ASFV E183L gene and is an important structural protein located on the inner envelope of the virus. It is involved in processes of virus assembly, apoptosis induction, and neutralizing antibody production. In this study, three specific monoclonal antibodies (mAbs) against ASFV p54 protein were generated, namely 6B11, 3E3, and 3C10, from mice who were immunized with recombinant prokaryotic p54-truncated protein. Three novel linear B cell epitopes, recognized by the mAbs, were revealed: 60AAIEEEDIQFINP72, 128MATGGPAAAPAAASAPAHPAE148, and 163MSAIENLRQRNTY175. The epitopes 60AAIEEEDIQFINP72 and 163MSAIENLRQRNTY175 were highly conserved in genotype I and II ASFV strains. In addition, the epitope peptide ELISA can be used for the detection of ASFV antibodies. Our work provides new insights for p54 antigenicity and an alternative tool for serological diagnosis of ASF.