The immunogram (quantitative TBNK immunophenotipisation) will be performed by flow cytometry, the antibody response will be determined by IVD ELISa.~Clinical biochemical and immunochemical (ECLIA) tests (including IL-6) will be performed on Cobas analyzers. Hemogram with differential blood picture will be performed with a hematology analyzer Sysmex XN 3100, examination of blood smears with CellaVision system or. microscope. Coagulation tests will be performed on BCS XP analyzers.~An in-house system for the analysis of SARS-CoV-2 virus fusion inhibitors on human cells will be used to detect the ability of antibodies from patients' serum to neutralize the virus and thus potential protection against re-infection. The system is quantitative, meaning that the titer of such antibodies could be determined, and thus the potential level of protection would be evaluated.
The study will look at the immunological characteristics of COVID-19 patients and determine neutralizing antibodies against SARS-CoV-2 virus.