A ‘very interesting’ discovery by Australian researchers may reveal the key to Covid immunity.health

Australian researchers have found a protein in the lungs that sticks and immobilizes the Covid-19 virus like Velcro. never become While infected with the virus, others suffer serious illnesses.

The study was led by Greg Neely, Professor of Functional Genomics at the Charles Perkins Centre, University of Sydney, in collaboration with postdoctoral researcher Dr Lipin Lu and PhD student Matthew Waller.their The findings were published Friday in the journal PLOS Biology.

Using human cells in tissue culture, the team searched the entire human genome for proteins that can bind to Sars-CoV-2, the virus that causes Covid-19.

This was done using a genetic engineering tool known as Crispr. Crispr turned on every gene in the human genome, allowing her to examine which of those genes give human cells the ability to bind to her Sars-CoV-2 spike protein. The spike protein is critical for the virus’ ability to infect human cells.

“This allowed us to find this new receptor protein, LRRC15,” Neely said.

“We then used the lungs of patients who died of Covid or other diseases and found that the lungs of severely Covid patients had large amounts of this LRRC15.”

LRRC15 is not present in humans until Sars-CoV-2 enters the body. It appears to be part of a new immune barrier that helps protect against serious Covid-19 infections while activating the body’s antiviral response.

Despite patients dying from Covid-19 producing LRRC15, researchers believe it wasn’t produced in sufficient amounts to protect or was produced too slowly to help.

“You see a lot of this protein when you look at the lungs of patients who have died from Covid,” Neely said. We were not able to see the patient’s lungs, and we would predict that survivors would have more of this protein than those who died of Covid.”

Another study from London looking at blood samples for LRRC15 found that protein in the blood was lower in severe Covid patients compared to mild Covid patients, supporting this theory.

“Our data suggest that people with higher levels of LRRC15 have less severe disease,” said Neely.

“The fact that there are natural immune receptors that we didn’t know about that lines our lungs that block and control viruses is very interesting.”

They also found that LRRC15 is also expressed in fibroblasts. Fibroblasts are the cells that control pulmonary fibrosis, a disease that causes lung tissue damage and scarring. Covid-19 can lead to pulmonary fibrosis, and this finding may have implications for Covid prolongation.

“We can now use this new receptor to design broad-acting drugs that can block viral infection or suppress pulmonary fibrosis,” said Neely. There is currently no good treatment for pulmonary fibrosis, he said.

Loo said LRRC15 “acts like molecular Velcro in that it sticks to the viral spike and pulls it away from the target cell type.”

Professor Stuart Turville, a virologist at the Kirby Institute at the University of New South Wales, said the finding is a “strong example” of what can happen when teams work together in Australia.

“Greg Neely’s team excels at what we call functional genomics,” said Turville.

“It’s the ability to wake up and turn off thousands of proteins at once, and this is very important when we look at new viruses. delivered the virus, and these collaborations are very powerful both now and in the future of emerging pathogens.”

It may be years before this discovery translates into a drug that can protect against viruses and other diseases, but Turville says the research is focused on innate immunity, the ability to act as soon as a virus appears. It deepens our understanding of the inherent human response.

“Understanding these pathways is important because it allows us to put the brakes on the virus so that other parts of the immune system can catch up and respond,” said Turville. .

“In some cases, these brakes may be so effective that the virus does not gain momentum. It could be one of the factors.”