The African Swine Fever Isolate ASFV-Kenya-IX-1033 Is Highly Virulent and Stable after Propagation in the Wild Boar Cell Line WSL

Johanneke D Hemmink; Hussein M Abkallo; Sonal P Henson; Emmanuel M Khazalwa; Bernard Oduor; Anna Lacasta; Edward Okoth; Victor Riitho; Walter Fuchs; Richard P Bishop; Lucilla Steinaa

doi:10.3390/v14091912

The African Swine Fever Isolate ASFV-Kenya-IX-1033 Is Highly Virulent and Stable after Propagation in the Wild Boar Cell Line WSL

Viruses. 2022 Aug 29;14(9):1912. doi: 10.3390/v14091912.

Affiliations

¹ Animal and Human Heath Program, International Livestock Research Institute, Nairobi 00100, Kenya.
² Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany.
³ International Livestock Research Institute, Nairobi 00100, Kenya.

Abstract

We describe the characterization of an African swine fever genotype IX virus (ASFV-Kenya-IX-1033), which was isolated from a domestic pig in western Kenya during a reported outbreak. This includes the efficiency of virus replication and in vivo virulence, together with genome stability and virulence, following passage in blood macrophages and in a wild boar lung cell line (WSL). The ASFV-Kenya-IX-1033 stock retained its ability to replicate in primary macrophages and retained virulence in vivo, following more than 20 passages in a WSL. At the whole genome level, a few single-nucleotide differences were observed between the macrophage and WSL-propagated viruses. Thus, we propose that the WSL is suitable for the production of live-attenuated ASFV vaccine candidates based on the modification of this wild-type isolate. The genome sequences for ASFV-Kenya-IX-1033 propagated in macrophages and in WSL cells were submitted to GenBank, and a challenge model based on the isolate was developed. This will aid the development of vaccines against the genotype IX ASFV circulating in eastern and central Africa.

Keywords: African swine fever virus; Kenyan isolate; genotype IX; virulence.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

African Swine Fever Virus*
African Swine Fever*
Animals
Cell Line
Kenya
Nucleotides
Sus scrofa
Swine
Vaccines, Attenuated

Substances

Nucleotides
Vaccines, Attenuated

Grants and funding

This research was funded by the Canadian International Development Research Centre (IDRC) Livestock Vaccine Innovation Fund (LVIF), grant no. 108514-002 (phase I), no. 109212-001 (phase II), the CGIAR Research Program on Livestock, and the CGIAR Consortium. In-kind contribution from GALVMED grant no. ILR-R39A0752S4 was also provided.