Development of a new effective African swine fever virus vaccine candidate by deletion of the H240R and MGF505-7R genes results in protective immunity against the Eurasia strain

J Virol. 2023 Oct 31;97(10):e0070423. doi: 10.1128/jvi.00704-23. Epub 2023 Sep 28.

Abstract

African swine fever (ASF) caused by ASF virus (ASFV) is a highly contagious and acute hemorrhagic viral disease in domestic pigs. Until now, no effective commercial vaccine and antiviral drugs are available for ASF control. Here, we generated a new live-attenuated vaccine candidate (ASFV-ΔH240R-Δ7R) by deleting H240R and MGF505-7R genes from the highly pathogenic ASFV HLJ/18 genome. Piglets immunized with ASFV-ΔH240R-Δ7R were safe without any ASF-related signs and produced specific antibodies against p30. Challenged with a virulent ASFV HLJ/18, the piglets immunized with high-dose group (105 HAD50) exhibited 100% protection without clinical symptoms, showing that low levels of virus replication with no observed pathogenicity by postmortem and histological analysis. Overall, our results provided a new strategy by designing live-attenuated vaccine candidate, resulting in protection against ASFV infection.

Keywords: ASFV; H240R; MGF505-7R; attenuation; protective efficacy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • African Swine Fever / immunology
  • African Swine Fever / prevention & control
  • African Swine Fever / virology
  • African Swine Fever Virus* / classification
  • African Swine Fever Virus* / immunology
  • African Swine Fever Virus* / pathogenicity
  • Animals
  • Gene Deletion*
  • Genes, Viral* / genetics
  • Sus scrofa / virology
  • Vaccines, Attenuated* / immunology
  • Viral Proteins / genetics
  • Viral Vaccines* / genetics
  • Viral Vaccines* / immunology
  • Virulence
  • Virus Replication

Substances

  • Vaccines, Attenuated
  • Viral Proteins
  • Viral Vaccines