Reduced Counts of Various Subsets of Peripheral Blood T Lymphocytes in Patients with Severe Course of COVID-19.

ABSTRACT

This study was intended to define T lymphocyte subsets in different clinical groups of COVID-19-infected patients to explore the interaction between T cell-mediated immune response and the severity of COVID-19 course. Lymphopenia in patients with severe COVID-19 was found. In patients with severe COVID-19 course, the absolute counts of CD3+, CD4+, and CD8+ T lymphocytes at admission were lower than on day 14 after discharge. Further analysis showed that the older were the patients with COVID-19, the more likely they developed severe infection. The results confirmed the significance of T lymphocytes in the clearance of the COVID-19.