A team of researchers including scientists from the Seattle Benaroya Research Institute at Virginia Mason has discovered a new pathway for protecting the cells from deadly viruses like the novel coronavirus or COVID-19 and also the Ebola virus.
The technique takes advantage of a screening method for seeking out the new genes, which can prevent infection. The study has been published in the journal Science. The team of researchers pinpoints two genes, which have already been the subject of biomedical studies. One gene is called the MHC class II transactivator, or CIITA. The second gene is known as the CD74, which is specifically a variant called p41.
Those genes have earlier been thought to be involved in the conventional immune responses that involve the T cells and B cells. The new discoveries, resulting from a screening technique called the transposon-mediated gene activation, gave an idea of a different method in which the genes block infection.
CIITA Causes Resistance in Human Cell Lines
The scientists found that the CIITA can cause resistance in the human cell lines by activating CD74 p41 that in turn disrupts the processing of the proteins on the coat of the Ebola virus protein. This stops the virus from getting the ability to infect its target cell. The same procedure blocks the entryway for a variety of coronaviruses, which include the SARS-CoV-2 virus that is causing the current pandemic.
"Uncovering these new cellular protection pathways is incredibly important for understanding how we disrupt or change the virus infection cycle to elicit better protection against viruses like Ebola or SARS-CoV-2," the senior study author Adam Lacy-Hulbert, principal investigator at the Benaroya Research Institute, mentioned in a news release. "And our new strategy helps us find mechanisms that have eluded conventional genetic screens."
The strategy can lead to new therapies that take place by blocking the activity of the cathepsin proteases. "Many viruses, including coronaviruses, use cathepsin proteases to help them infect cells. ... Thus, this antiviral mechanism has evolved to work against many different viruses," Case Western Reserve University's Anna Bruchez, the study's lead author mentioned.
The co-author of the study Lynda Stuart stated that the new technique of screening can fill the gaps in scientists' knowledge about the cellular mechanisms that block the viral infections. "We really need therapies that can block all viruses, including unknown future pathogens," Stuart mentioned. "To do that, we need to find common pathways that viruses target, and then develop approaches to block those vulnerabilities. Our work demonstrates one way in which cells can be modified to do this."