Evaluation of IGG-dependent humoral and cellular immunity in persons after covid-19 and in healthy volunteers

ABSTRACT

43 individuals (medical workers) were examined, 15 of them suffered from COVID-19;7 persons had negative PCR tests, however, there were signs of a respiratory infection in the anamnesis;21 participants denied having had COVID-19 and any respiratory infections in the past year. The serum level of neutralizing IgG to S-Trimer Protein SARS-Cov-2 was determined. The number of antigen-recognizing receptors of B-lymphocytes represented by membrane IgG to S-Trimer Protein SARSCov-2 was also evaluated. It was found that in some of the subjects who consider themselves not sick, antibodies and antigen-recognizing receptors of B-lymphocytes are not detected. However, a significant proportion of healthy individuals (67 %) were found to have elevated levels of serum antibodies and a high number of antigen-recognizing receptors. Persons who recovered from COVID-19 had elevated levels of serum IgG antibodies and high levels of antigen-recognizing receptors of B-lymphocytes in peripheral blood. However, in patients with a more severe course of infection who were prescribed glucocorticosteroids during the treatment, the serum IgG and lymphocyte receptor levels were lower. Individuals who noted respiratory infection of varying severity during the epidemic period, but not confirmed by PCR for COVID-19 and did not receive glucocorticosteroids, there were high levels of serum neutralizing IgG antibodies and a high content of antigenrecognizing receptors of peripheral blood B-lymphocytes, represented by membrane IgG to S-Trimer Protein SARS-Cov-2.