Researchers at the University of Connecticut have identified a compound that can successfully block the Porcine Reproductive and Respiratory Syndrome (PRRS) virus.
The UConn research team identified CD163, a cell surface receptor that is expressed in pig monocytes and macrophages that the virus needs to get into the pig target cells. They hypothesized that a small molecule blocking this receptor would block infection, the release said.
PRRS causes about $600 million worth of losses per year in the United States.
The university team is Young Tang, assistant professor of animal science, and Antonio Garmendia, professor of pathobiology and veterinary science.
In collaboration with Atomwise, a biotechnology company in San Francisco, the researchers used artificial intelligence technology to screen millions of compounds and identify small molecules that could block CD163.
After identifying the best candidates, the company sent Tang and Garmendia 74 small molecules – predicted to have the highest potential of targeting the receptor – to test in their labs, the release said.
“There are many strains of the PRRS virus, making attempts to create broadly protective vaccines very challenging,” the article said.
“Vaccines work by spurring the body to produce antibodies specific for the strain of virus used as the vaccine. Because the virus mutates so quickly and has so many strains, it is impossible to vaccinate pigs against every variant.”
The researchers then tested the small molecules from Atomwise with both the American and European types of the virus and found that B7 effectively blocks both types. In addition, these types are genetically diverse, making this finding’s broad applicability significant.
Coupled with existing vaccines, this compound would provide a second line of defence against PRRS, the researchers said in the article.
Vaccines prompt the creation of antibodies, and the small molecule would block the virus’ attachment to cell receptors, reducing further virus shedding and transmission.
“This would protect animals better than a vaccine alone,” Garmendia said in the release. “It could have a significant impact.”
They are seeking a patent and partners to commercialize their work. The next step is tests with animals; so far the tests have been in the lab.
