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The researchers explained that TLR-genes help produce a family of protein receptors on the surface of human cells that play an important role in the recognition of pathogens. They said these receptors recognise infectious agents like bacteria and viruses in the body and activate the immune system.
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While TLR7 function had so far never been associated with an inborn error of immunity, the new findings, according to the scientists, indicate that its role is essential for protection from the novel coronavirus. “So it seems that the virus can replicate undisturbed because the immune system does not get a message that the virus has invaded,” explained geneticist Alexander Hoischen.
The discovery, according to the scientists, not only provides more insight into the fundamental workings of the immune system, but it may also have important consequences for the treatment of severely ill COVID-19 patients.