COVID-19 Immunity Can Be Developed In The Absence Of Antibodies - Swedish Scientists

COVID-19 immunity can be developed in the absence of antibodies - Swedish scientists

Researchers at the Karolinksa Institute have found T cells in people who test negative for antibodies, which play an important role in the body's acquired immune response.

Photo: Pille-Riin Priske / Unsplash

Swedish scientists conducted an immunological analysis of samples from 200 patients, including those who suffered from COVID-19 in a mild or asymptomatic form, the BBC reports. Antibodies were not detected in 30% of those examined, but the so-called T-cell immunity was found, and it was twice as high as in people with antibodies. T cells (or T lymphocytes) store information about previously acting antigens and contribute to the formation of immunity to infectious diseases.

The researchers concluded that the level of herd immunity could be much higher, since all over the world scientists in their estimates rely solely on the number of patients with antibodies. This is not surprising, since the analysis for T cells is more complex and is carried out manually in specialized laboratories, it is impossible to carry out mass testing of the poem.

According to one of the authors of the study, associate professor at Karolinska University Marcus Buggert, additional analysis is needed in order to assess the protective properties of T cells. They may protect a person from disease, but they cannot protect against infection and the spread of infection. In addition, it is not yet known how long the T-cell response is immune to coronavirus.

“We are probably now underestimating the number of people who have some kind of immunity. Whether this means that such people are fully protected or in the future their disease will be milder or asymptomatic, it is difficult to say now,”the scientist said.

Professor Danny Altmann of Imperial College London called the Swedish study “reliable, impressive and thorough,” and said it added evidence to support the hypothesis that the percentage of people with acquired immunity is much higher.

“Testing for antibodies alone does not tell the whole story,” Altmann said.