The continued spread and regular outbreaks of African swine fever (ASF) have severely threatened the pig-related industries, causing economic losses. African swine fever virus (ASFV) encoded more than 150 different proteins, but the biological characteristics of the majority of these proteins remain unknown. In this study, we leveraged the Phage ImmunoPrecipitation Sequencing (PhIp-Seq) platform to perform an exhaustive serological analysis of ASFV to characterize the specific reactivities of serum anti-ASFV IgG antibodies against the ASFV proteome at peptide resolution. High-resolution epitope mapping of the ASFV antigens was conducted, and a total of 29 ASFV antigens with high immunogenicity were identified, 14 of which, to the best of our knowledge, have not been previously identified as serological antigens. The immunogenicity of these 29 antigens was evaluated, and their conservation was statistically analyzed across 169 ASFV strains. We found that the uncharacterized protein DP238L is a conserved antigen that is widely hit within the population. The immunogenicity of DP238L and multi-epitope recombinant proteins was validated by immunoblotting and animal immunization trials, confirming the immunogenicity of the identified antigens and the reliability of the PhIp-Seq based epitope mapping strategy. These findings provide insights into the structures and functions of antigen proteins and identify crucial targets for ASFV detection and vaccine development.

African swine fever virus (ASFV) is a highly contagious pathogen that causes pigs to develop high fever, vomiting, diarrhea, and respiratory distress, with an exceptionally high case fatality rate. Unfortunately, vaccine development is hindered by a limited understanding of the structure and function of the protein encoded by ASFV, as well as the mechanisms underlying infection and immunity. Among these factors, the lack of effective cellular epitopes represents a major obstacle to vaccine development. Epitopes serve as the smallest structural units capable of inducing immune responses and are critical targets for both vaccine design and diagnostic reagent development. Therefore, it is imperative to investigate antigens with high immunogenicity and elucidate their correlation with protective immune responses to provide scientific insights and a theoretical foundation for developing safe and effective ASFV vaccines. Currently, thorough reviews on the identification and functional characterization of ASFV antigenic epitopes remain scarce. To address this gap, this paper provides a comprehensive review of ASFV epitopes and their identification strategies. It initiates with a systematic classification of ASFV antigenic epitopes, followed by an extensive discussion of various methods for identifying ASFV epitopes, along with their advantages and limitations. Furthermore, the paper summarizes existing databases of characterized ASFV antigenic epitopes and highlights the most biologically significant ones. In addition, the paper explores emerging applications of ASFV epitopes while addressing the technical challenges in epitope‐based research to provide valuable insights for ASFV vaccine development and production.

Porcine reproductive and respiratory syndrome (PRRS), caused by PRRSV, causes substantial economic losses in the swine industry. Because viral variability and host genetic complexity limit conventional control, identifying host genetic factors associated with PRRS resistance through genomic approaches is important for disease-resistant breeding. In this study, 699 pigs were immunized with a PRRSV vaccine, 135 were selected for PRRSV infection experiments, and 133 were retained for whole-genome resequencing after two-stage phenotypic screening based on post-immunization and post-infection profiles. Genome-wide selection-signal analysis identified 12 highly differentiated regions (F_st > 0.15), annotated to 11 candidate genes: NFXL1, NIPAL1, CHIC2, LOC100623351, LOC100513671, LOC100513484, CENPC, STAP1, UBA6, GNRHR, and LOC100512727. The original exploratory GWAS identified candidate association signals, including signals annotated to PYGM, NFXL1, KIAA1324L, and FLNC; after PC1/PC2 adjustment, NFXL1 retained exploratory support, and additional exploratory signals were observed. Public PRRSV-related transcriptomic datasets provided additional expression-level evidence, with NIPAL1 and PYGM showing increased expression in PRRSV-infected porcine alveolar macrophages. Functional enrichment and variant-level analyses supported the biological relevance of the prioritized candidate gene set, particularly the chromosome 8 NFXL1 region, where the A-C-G haplotype was more frequent in resistant pigs. These findings provide useful genetic clues for further validation and PRRS resistance breeding.