The severity of the COVID-19 disease may depend on the levels of a protein

(StudyFinds) – A protein that scientists say sends the ‘don’t eat me’ signal to the human immune system may be responsible for more severe cases of COVID-19. Researchers at the University of Kent have found that higher levels of this protein on the surface of infected cells can prevent the immune system from doing its job.

Although many patients infected with SARS-CoV-2, the virus that causes COVID-19, will only develop mild symptoms, others will experience serious and potentially fatal reactions. COVID-19 is already responsible for nearly 700,000 deaths in the United States. The new findings reveal that the CD47 protein may play a major role in these deaths.

The “don’t eat me” signal fools the immune system

CD47 sends a signal that prevents the immune system’s defenses from accidentally destroying healthy cells. However, the researchers found that when SARS-CoV-2 infects human cells, more CD47 appears on the surface of the cells. The team adds that this likely prevents the immune system from recognizing infected cells as a threat. Without the immune system attacking these cells, the virus can continue to replicate and cause more severe symptoms.

The study’s authors add that specific risk factors for serious COVID-19 infections – like old age and pre-existing conditions like diabetes – also show a link with higher levels of the CD47 protein. High CD47 levels also contribute to high blood pressure – another risk factor for serious complications from COVID.

The researchers note that therapies targeting CD47 are already in development. Their findings could help improve their effectiveness during the COVID-19 pandemic.

“This is exciting. We may have identified a major factor associated with severe COVID-19. This is a big step in the fight against the disease and we can now expect further progress in the treatment design, ”says Professor Martin Michaelis in the press release.

“This additional information on the disease processes underlying COVID-19 may help us design better therapies, as well as appreciate the importance of the breadth of research being conducted. Thanks to this path, we have made a major breakthrough and shown that the fight against the disease continues, ”adds Professor Jindrich Cinatl of Goethe University-Frankfurt.

The study appears in the journal Current issues in molecular biology.