Differentiation of the Cytokine Profile Modified by SARS-CoV-2 and Influenza Virus in an In Vitro Experiment.

We compared changes in the expression of the cytokine profile modified by SARS-CoV-2 and influenza virus in an in vitro experiment. A mixed population of immunocytes (T-helpers, B cells, NK cells, cytotoxic T lymphocytes, and monocytes) was isolated from peripheral venous blood samples (n = 32) of conditionally healthy male donors aged 25-35 years. The modifying factors were recombinant adenovirus particles of 26 and 5 serotypes containing the gene encoding S protein of SARS-CoV-2, as well as vaccine antigens (hemagglutinins) of influenza virus type A (H1N1 and H2N3) and type B. Multidirectional changes in the cytokine production was revealed upon exposure to SARS-CoV-2 antigens: stimulation of the expression of IL-1β and IL-8 and suppression of the production of IL-4 and IL-6; changes in the expression of IL-8 and IL-6 were more pronounced after combined exposure (SARS-CoV-2 + influenza virus). Influenza virus antigens predominantly stimulated the expression (IL-8), while the maximum cytokine-producing effects were noted after combined exposure to SARS-CoV-2 and influenza virus antigens. The obtained results extend the understanding of the pathogenic mechanisms associated with persistence of SARS-CoV-2 and influenza virus. The modifications of the cytokine profile produced by the viruses and verified in vitro allow predicting and monitoring the course of diseases.