Coronavirus If they lack the NKG2C receptor
A study from the Medical University of Vienna has found that COVID-19 patients that suffer with more severe symptoms have something in common.
They seem to be missing the NKG2C receptor, which is the case for roughly four percent of the population.
The researchers at the Medical University of Vienna Centre for Virology, in collaboration with doctors at the Vienna Favoriten Hospital and led by Elisabeth Puchhammer-Stockl, were recently published in the Genetics in Medicine journal.
Their main conclusion is that people with a partial or complete absence of the NKG2C receptor tend to develop severe courses of COVID-19. This genetic variation was found mainly in people infected with coronavirus who had to be hospitalised.
“The absence of the receptor was especially frequent in patients who had to be treated for COVID-19 in intensive care units, irrespective of age or sex,” Puchhammer-Stockl said in the press release.
The note recalls that the interaction between the SARS-CoV-2 virus and the human immune system significantly influences the course and severity of COVID-19 disease in each patient.
In this context, “the antiviral immune response by natural killer (NK) cells is normally an important step in combating viral replication during the early phase of infection,” she added.
So-called natural killer (NK) cells – an important lymphocyte of the immune system for the defence of the body – have specific activating receptors on their surface, including the NKG2C receptor, which communicates with an infected cell through one of its specific structures, HLA-E.
This interaction leads to the destruction of virus-infected cells, but “about 4 percent of the population naturally lacks the activating NKG2C receptor due to genetic variation, and about 30 percent only partially possess the receptor,” the scientists note.
These findings could open the door to new ways of combating the pandemic, said Puchhammer-Stockl.
Above all, “this part of the immune response could be an important target for [the development of] drugs that could help prevent severe COVID-19 disease.”