Mucosal and cellular immune responses elicited by nasal and intramuscular inoculation with ASFV candidate immunogens

Front Immunol. 2023 Sep 1:14:1200297. doi: 10.3389/fimmu.2023.1200297. eCollection 2023.

Abstract

African swine fever (ASF) is an infectious disease caused by African swine fever virus (ASFV) that is highly contagious and has an extremely high mortality rate (infected by virulent strains) among domestic and wild pigs, causing huge economic losses to the pig industry globally. In this study, SDS-PAGE gel bands hybridized with ASFV whole virus protein combined with ASFV-convalescent and ASFV-positive pig serum were identified by mass spectrometry. Six antigens were detected by positive serum reaction bands, and eight antigens were detected in ASFV-convalescent serum. In combination with previous literature reports and proteins corresponding to MHC-II presenting peptides screened from ASFV-positive pig urine conducted in our lab, seven candidate antigens, including KP177R (p22), K78R (p10), CP204L (p30), E183L (p54), B602L (B602L), EP402R-N (CD2V-N) and F317L (F317L), were selected. Subunit-Group 1 was prepared by mixing above-mentioned seven ASFV recombinant proteins with MONTANIDETM1313 VG N mucosal adjuvant and immunizing pigs intranasally and intramuscularly. Subunit-Group 2 was prepared by mixing four ASFV recombinant proteins (p22, p54, CD2V-N1, B602L) with Montanide ISA 51 VG adjuvant and immunizing pigs by intramuscular injection. Anticoagulated whole blood, serum, and oral fluid were collected during immunization for flow cytometry, serum IgG as well as secretory sIgA antibody secretion, and cytokine expression testing to conduct a comprehensive immunogenicity assessment. Both immunogen groups can effectively stimulate the host to produce ideal humoral, mucosal, and cellular immune responses, providing a theoretical basis for subsequent functional studies, such as immunogens challenge protection and elucidation of the pathogenic mechanism of ASFV.

Keywords: ASFV-convalescent pig serum; African swine fever virus (ASFV); immunogenicity assessment; mass spectrometry identification; recombinant protein expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic
  • Adjuvants, Pharmaceutic
  • African Swine Fever Virus*
  • African Swine Fever*
  • Animals
  • Histocompatibility Antigens Class II
  • Immunity, Cellular
  • Immunization
  • Swine
  • Vaccination

Substances

  • Adjuvants, Immunologic
  • Adjuvants, Pharmaceutic
  • Histocompatibility Antigens Class II

Grants and funding

This study was supported by National Key Research and Development Program of China (2019YFE0107300), Jiangsu Agricultural Science and Technology Independent Innovation Fund (CX(21)3124), National natural science foundation of China (32273011), the Independent Research Project Program of Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base, Ministry of Science and Technology, China (2022-SBGJZZ-6), and Jiangsu Association for Science and Technology Youth Science and Technology Talents Support Project (TJ-2023-093).