Антитела к рецептор-связывающему домену спайкового белка SARS-COV-2: связь с возрастом, пневмонией, длительностью периода после COVID-19

Despite the rapid accumulation of facts about the humoral immune response in COVID-19, there are still no evidencebased answers to questions about the factors influencing the level and duration of the detection period of antibodies to SARS-CoV-2 in the blood.Objective: To assess the prevalence, clinical and demographic associations of IgG antibodies to RBD of the SARSCoV-2 spike protein at different times after COVID-19.Materials and methods. Residents of the Altai region of Russia, Caucasians aged 20-93 years, who had COVID-19 from May 2020 to February 2021 (n = 314), took part in a onetime observational study. The level of antibodies in the blood was measured by enzyme-linked immunosorbent assay 1-14 months after the onset of the clinical manifestation of COVID-19.Results. Anti-RBD IgG antibodies of the SARS-CoV-2 spike protein were detected in 86.9% of the study participants. The dependence of the antibody titer on the duration of the period after COVID-19 was not revealed. The antibody titer was positively correlated with the complication of COVID-19 pneumonia and the volume of lung tissue lesions. The presence of pneumonia COVID-19 and the volume of lung tissue lesions are positively associated with age. Age positively correlated with antibody titer regardless of the pneumonia COVID-19 in the anamnesis.Conclusion. IgG antibodies to RBD of the SARS-CoV-2 spike protein are present in most of the COVID-19 patients. The titer of these antibodies in adults depends on age, complications of pneumonia COVID-19, and probably persists up to 14 months after the first symptoms of infection appear.Несмотря на быстрое накопление фактов о гуморальном иммунном ответе при COVID-19, пока нет доказательных ответов на вопросы о факторах, влияющих на уровень и длительность периода обнаружения антител к SARS-CoV-2 в крови.Цель: оценить распространенность наличия, клинические и демографические ассоциации антител IgG к RBD спайкового белка SARS-CoV-2 в разные сроки после COVID-19.Материалы и методы. В одномоментном обсервационном исследовании приняли участие жители Алтайского края России, европеоиды, в возрасте от 20 до 93 лет, переболевшие COVID-19 в период с мая 2020 г. по февраль 2021 г. (n=314). Уровень антител в крови измеряли через 1–14 месяцев от начала клинической манифестации COVID-19 методом иммуноферментного анализа.Результаты. Антитела IgG к RBD спайкового белка SARS-CoV-2 обнаружены у 86,9% участников исследования. Не выявлено зависимости титра антител от давности COVID-19. Титр антител положительно коррелировал с осложнением пневмонией COVID-19 и объемом поражений легочной ткани. Наличие пневмонии COVID-19 и объем поражений легочной ткани положительно связаны с возрастом. Возраст положительно коррелировал с титром антител независимо от наличия пневмонии COVID-19 в анамнезе.Заключение. Антитела IgG к RBD спайкового белка SARS-CoV-2 имеются у большей части переболевших COVID-19. Титр этих антител у взрослых зависит от возраста, осложнения пневмонией COVID-19 и может сохраняться до 14 месяцев после появления первых симптомов инфекции

Antibodies to the Spike Protein Receptor-Binding Domain of SARS-CoV-2 at 4–13 Months after COVID-19

Identification of factors behind the level and duration of persistence of the SARS-CoV-2 antibodies in the blood is assumed to set the direction for studying humoral immunity mechanisms against COVID-19, optimizing the strategy for vaccine use, antibody-based drugs, and epidemiological control of COVID-19. Objective: This study aimed to study the relationship between clinical and demographic characteristics and the level of IgG antibodies to the RBD of SARS-CoV-2 spike protein after COVID-19 in the long term. Residents of the Altai Region of Western Siberia of Russia, Caucasians, aged from 27 to 93 years (median 53.0 years), who recovered from COVID-19 between May 2020 and February 2021 (n = 44) took part in this prospective observational study. The titer of IgG antibodies to the RBD of SARS-CoV-2 spike protein was measured repeatedly in the blood at 4–13 months from the beginning of the clinical manifestation of COVID-19 via the method of enzyme-linked immunosorbent assay. The antibody titer positively correlated with age (p = 0.013) and COVID-19 pneumonia (p = 0.002) at 20–40 and 20–24 weeks from the onset of COVID-19 symptoms, respectively. Age was positively associated with antibody titer regardless of history of COVID-19 pneumonia (beta regression coefficient p = 0.009). The antibody titer decreased in 15 (34.1%) patients, increased in 10 (22.7%) patients, and did not change in 19 (43.2%) patients from the baseline to 48–49 weeks from the onset of COVID-19 symptoms, with seropositivity persisting in all patients. Age and COVID-19 pneumonia are possibly associated with higher IgG antibodies to the spike protein RBD of SARS-CoV-2 following COVID-19 in the long term. Divergent trends of anti-RBD IgG levels in adults illustrate inter-individual differences at 4–13 months from the onset of COVID-19 symptoms