Procedures
RBD
ADVERSE EVENTS, BLOOD, VIRUS
The Gam-Covid-Vac (Sputnik V) vaccine comprises two vector components at 10Along with the vaccination visits (hospitalization from one day before vaccination to one day after vaccination) on days 1 and 21, the additional observation visits were planned for day 28 ( ± 2 days), day 42 ( ± 3 days), day 90 ( ± 3 days) and day 180 ( ± 14 days). Several additional observation visits were also organized remotely as telemedicine consultations. If necessary, the volunteers were to be invited to the center for an unscheduled visit. The participants were instructed to complete a paper diary to record local and systemic adverse events (AEs). The participants were encouraged to contact center staff by telephone as required (for example, if AEs were registered or for consultation). Otherwise, the information on registered AEs was recorded from diaries at the next observation visit or In addition to screening and vaccination visits, the participants underwent physical examination (palpation, auscultation, measurement of systolic and diastolic blood pressure, heart rate, body temperature, and others) on days 14, 28, 42, 90, and 180. Electrocardiogram and coagulogram were performed at screening and on day 28. Blood tests, including a complete blood count and biochemical analysis, as well as a urine test, were done at screening, on vaccination days, and on day 28.The antibodies to the spike (S) protein SARS-CoV-2 and its receptor-binding domain (RBD) of SARS-CoV-2 were measured before the component I (day 1) and II (day 21) injections and on days 28, 42, 90, and 180 using ELISA commercial SARS-Cov-2-IgG-ELISA-BEST (Vector-Best, Russia) and SARS-CoV-2-RBD-ELISA-Gamaleya (N. F. Gamaleya National Research Centre for Epidemiology and Microbiology, Russia) test systems, correspondingly, according to manufacturers’ instructions. The level of neutralizing antibodies was analyzed using the microneutralization test with different variants of the SARS-CoV-2 virus: Wuhan B.1.1.1 hCoV-19/Russia/Moscow_PMVL-1/2020, Delta B.1.617.2 hCoV-19/Russia/SPE-RII-32758S-PMVL-CS-SPE32758/2021, Omicron BA.5 B.1.1.529 hCoV-19/Russia/SPE-RII-25357S/2022.The cell-mediated immune response was studied before the component I vaccination (on day 1) and on day 28 by detecting antigen-specific proliferating CD4+ and CD8+ T cells by flow cytometry and quantifying interferon-γ release of peripheral blood mononuclear cells (PBMCs) upon antigen restimulation using ELISA method. Methods are described in detail in appendix pp 1-3.