Scientists in Germany and Scotland have pinpointed a gene in the DNA of pigs that is needed by the African Swine Fever (ASF) virus, a move they believe could lead to the development of pigs resistant the deadly pig disease.
A team of researchers, led by the Friedrich-Loeffler Institute, working with the Roslin Institute, found that the gene, which is involved in the pig immune system, is essential for replication of the ASF virus. The finding raises the possibility of amending the gene, using gene editing, to develop pigs that are resistant to the disease, helping to manage the infection, for which no vaccine or treatment is currently available.
The team sought to pinpoint which pig genes were needed for the virus to replicate. In lab tests, they examined a collection of pig cells, each one edited to lack a specific gene compared with the rest, to observe how they responded to the ASF virus.
Their study, published in Scientific Reports, pointed towards a suite of genes that produce proteins associated with the immune response to infections, known as the MHC-II complex, as key to enabling the virus to take hold.
Researchers were able to determine that a single protein in the MHC-II complex, known as SLA-DM, is essential for replication of the virus in cells.
They anticipate that editing the SLA-DM gene may enable the development of pigs that are resistant to ASF, and so help to mitigate the impact of the virus and are keen to undertake further research to understand the biological processes in which virus particles and SLA-DM proteins interact.
This collaboration brought together the Friedrich-Loeffler Institute’s capacity to study ASF virus in the lab, and gene-editing tools developed at the Roslin Institute.
Dr Katrin Pannhorst, from Friedrich-Loeffler-Institute, said: “The collaboration with the Roslin Institute enabled us to use a CRISPR/Cas9-based gene knockout library to identify the cellular MHC II protein SLA-DM as a crucial factor in ASFV infection. This exciting finding not only improves our understanding of the biology of ASFV, but may also allow the development of new control measures.”
The Roslin Institute’s Dr Finn Grey added: “Our study points to genes that are candidates for editing to develop pigs resistant to African Swine Fever. Our study identifies target genes for editing to develop pigs resistant to ASF. Although more work is required, this finding represents an important first step towards the generation of ASF-resistant pigs.”