Scientists: health workers have a special immunity to COVID-19, thanks to the IFI27 protein 
covid “patients, special immunity to coronavirus, which cannot be determined through antibody tests. This is stated in a study published in the scientific journal Nature.
They conducted a study of the immunity of about 60 employees of a clinic in the UK for the level of antibodies and latent infections. According to the results of the analyzes, it turned out that for four months their PCR tests were always negative, however, antibodies to coronavirus were not found in their blood, even if their colleagues in the clinic were infected with COVID-19.
After examining the blood of the subjects, scientists determined that 20 of them had an increased concentration of T cells, and in 19 people they found an additional immune protein called IFI27. Theoretically, it may indicate that their body has previously been in contact with COVID-19.
Scientists suggest that the immunity of such people reacts so quickly to the coronavirus that it cannot even leave antibodies behind. At the same time, such a powerful protection could well have developed after the contact of medical workers with other previously known human coronaviruses that cause colds.
Earlier, Academician of the Russian Academy of Sciences Vadim Pokrovsky said that protection from COVID-19 does not depend on the number of antibodies in the body. “In fact, there is no direct link between the amount of antibodies and protection against coronavirus. This is where more complex cellular immunity comes in. But we chose such an average indicator, which is taken as the basis for the provision of codes, “he said.