The researchers, with the help of their machine learning tool, determined that severe COVID-19 is largely associated with a weakened response from two well-known immune cells – natural killer (NK) cells and T cells.
“NK cells, which humans are born with and are the body’s first line of defense against infection, are known for their ability to destroy viruses and cancer cells. NK cells also help produce a range of immune system proteins called cytokines. One cytokine, interferon “gamma, is a key activator of immune cells. Acting in concert with interferon gamma, NK cells mount an immediate and coordinated defense against viral infections,” says Doctor Cooper-Knock.
“NK cells are like the generals directing the war. They mobilize other immune cells, telling them where to go and what to do. We found that in people with severe coronavirus infection, critical genes in NK cells are expressed less, so there’s a less robust immune response. The cell isn’t doing what it’s supposed to do, “he adds.
The senior author of the study Professor Michael P Snyder from Stanford University notes a similarity between COVID-19 risk genes and harmful variants of the BRCA genes, which are used to predispose some people to breast and ovarian cancers.
Professor Snyder said, “Our findings lay the foundation for a genetic test that can predict who is born with an increased risk for severe COVID-19.
“Imagine there are 1,000 changes in DNA linked to severe COVID-19. If you have 585 of these changes, that might make you pretty susceptible, and you’d want to take all the necessary precautions,” he adds.