Peculiarities of immune response in patients with COVID-19

Baranova N.I., Aschina L.A., Bolgova A.I.

PIUV – a branch of the Federal State Budgetary Educational Institution of Higher Professional Education of the Russian Ministry of Health, Penza, Russia

Aim of the study: analysis of peculiarities of immune response in patients with COVID-19 in comparison with such in healthy subjects.
Methods. Subjects of the study were 96 patients with moderate and severe COVID-19 infection. Immunological analysis included chemiluminescence evaluation of phagocytic activity of cells, study of cytokines (IL-18, FNO-α, IL-4, IL-10, IFN-γ) in supernatants, subpopulations of T and B lymphocytes, functional activity of T lymphocytes.
Results. Immunological defects found in patients with COVID-19 in comparison with the control group were: an elevated level of leukocytes, neutrophils, monocytes and decrease of normalized maximum intensity of neutrophils luminescence (Imax). Prominent deviations in humoral immunity factors discovered were: an increased levels of IgA and IgG, reduced IgM; in the system of cytokines – increased spontaneous and induced production of IL-18, decreased induced FNO-α, increased spontaneous IL-4. As for the immune T-system, we revealed a statistically significant decrease of functional and quantitative indices of T cells and CD3+CD8+ cytotoxic lymphocytes in the patients with COVID-19 compared to the control group.
Conclusion. The revealed immune defects in the systems of innate and adaptive immunity of patients with COVID-19 contribute to the understanding of immunopathogenesis of the disease and render the necessity of further research into the immune mechanisms of recovery after primary infection.