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

• Published in: Journal of clinical medicine Vol. 11; no. 14; p. 4053
• Main Authors: Kolosova, Evgeniia A., Shaprova, Olga N., Shanshin, Daniil V., Nesmeyanova, Valentina S., Merkuleva, Iuliia A., Belenkaya, Svetlana V., Isaeva, Anastasiya A., Nikitin, Artem O., Volosnikova, Ekaterina A., Nikulina, Yuliya A., Nikonorova, Marina A., Shcherbakov, Dmitry N., Elchaninova, Svetlana A.
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 13.07.2022; MDPI
• Subjects: Antibodies; Chromatography; Clinical medicine; Cloning; Coronaviruses; COVID-19; Enzymes; Infections; Medical research; Plasmids; Proteins; Severe acute respiratory syndrome coronavirus 2; Sodium; Vectors (Biology); United States > US; Latvia; Russia; COVID-19; SARS-CoV-2; pneumonia; receptor-binding domain; spike protein; antibodies; age
• DOI: 10.3390/jcm11144053
• ISSN: 2077-0383

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.