Scientists in Australia, the UK and the US have discovered a protein in the lungs that blocks Covid-19 infection and forms the body’s natural protective barrier against the coronavirus. It is estimated that not all people have this protein to the same extent, which probably plays a role in how badly someone gets Covid-19.

The LRRC15 protein is an integrated receptor that binds to the SARS-CoV-2 virus, preventing it from spreading and infecting other cells. The unexpected discovery opens up a whole new area of ​​immunological research and potentially opens up opportunities for developing new drugs to prevent infection with this and other viruses. However, it will be years before this becomes a reality.

Researchers at the University of Sydney, led by professor of genomics Greg Neely, as well as the universities of Oxford and Yale, who made their respective publications in the biological journal PLoS Biology, confirmed the action of the protein in three independent studies.

“We think it acts like Velcro (adhesive tape), like a molecular Velcro that sticks to the virus and then pulls it away from the target cells,” said PhD researcher Liping Lu.

We can use the receptor to develop drugs

“For me, as an immunologist, it is incredibly interesting that there is a natural immune receptor that we did not know about until now, which covers our lungs, blocking and controlling the coronavirus. We can now use this new receptor to develop broad-spectrum drugs that will block viral infection or even suppress pulmonary fibrosis,” said Dr. Neely.

The coronavirus infects humans by using its spike protein to bind to a specific receptor on human cells, the ACE2 protein (enzyme). Lung cells have high levels of ACE2 receptors, which explains why the coronavirus often causes serious problems in the lungs of patients.

As with the ACE2 receptor, LRRC15 is a coronavirus receptor but does not support infection. Instead, it “binds” and immobilizes the virus, thereby preventing other vulnerable cells from infecting. The LRRC15 protein is present in many parts of the body such as the lungs, skin, tongue, placenta, lymph nodes, etc.

A British study found that people with more severe Covid-19 had lower blood levels of LRRC15 than those with milder disease. Therefore, people with lower levels of this protein are more likely to become more seriously ill with Covid-19, while the opposite is true for those with high levels of LRRC15 in their bodies and thus a better natural defense against the virus.

Source: RES-IPE