Properties of RBD specific IgG from COVID-19 patients and Sputnik V vaccinated individuals

About authors

1 Рeoples’ Friendship University of Russia (RUDN University), Moscow, Russia

2 Gamaleya National Research Center for Epidemiology and Microbiology, Moscow, Russia

Correspondence should be addressed: Vladimir A. Gushchin
Gamaleya, 18, str. 9, Moscow, Russia; moc.liamg@adainawow

About paper

Funding: this research was funded by the Ministry of Health of the Russian Federation, Government assignments number № АААА - А20-120113090054-6, Prof. Olga A. Burgasova was also supported by the RUDN University Strategic Academic Leadership Program.

Author contribution: LV Generalova, IV Grigoriev — research planning, experiments preparation and execution, data interpretation and paper draft preparation; IS Kruzhkova, LV Kolobukhina — data interpretation and paper draft preparation; DV Vasina, AP Tkachuk, OA Burgasova, VA Gushchin — research planning, data interpretation and paper draft preparation.

Compliance with ethical standards: the study was approved by the ethics committee of the First Moscow Infectious Diseases Hospital (protocol № 11/А dated November 16, 2020); informed consent was obtained from all study participants.

Received: 2022-01-23 Accepted: 2022-02-08 Published online: 2022-02-16

SARS-CoV-2 specific antibody response is a generally accepted measure of postinfection and vaccination-induced immunity assessment. The dynamics of avidity maturation and neutralizing activity of virus-specific immunoglobulins G during the SARS-CoV-2–associated coronavirus infection was studied in cohorts of vaccinated volunteers and COVID-19 patients. 4–6 months after vaccination, neutralization activity was low compared to hospitalized patients (medians 57.4% vs 86.4%). On the opposite, the avidity indices in vaccinated volunteers were significantly higher (median 76.7%) than among hospitalized patients (median 61.4%). During the acute phase of the disease (14–16 days PI), post-vaccination patients have also higher avidity indices than primary patients (medians 43.5% vs 20.4%). Our results suggest that in long-term perspective antibody affinity maturation rate is higher after vaccination than after a natural infection. We demonstrated that Sputnik V vaccination leads to formation of high-avidity IgG, which persists for at least 6 months of observation. These results also indicate the presence of protective efficacy markers for at least 4–6 months after the vaccination or a previous illness and gives grounds for the half-year time period chosen for booster immunization with Sputnik V in Russia.

Keywords: SARS-CoV-2, SARS-COV-2, vaccination, antibody avidity, virus neutralization, immune memory, Sputnik-V