Abstract
Objectives: With the availability of vaccines, commercial assays detecting anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies evolved toward quantitative assays directed to the spike glycoprotein or its receptor-binding domain (RBD). The objective was to perform a large-scale, longitudinal study involving health care workers (HCWs), with the aim of establishing the kinetics of immune response throughout the 9-month period after receipt of the second dose of the BNT162b2 vaccine.
Methods: Quantitative determination of immunoglobulin (Ig) G antibodies against the RBD of the S1 subunit of the spike protein of SARS-CoV-2 on the Alinity systems.
Results: The highest levels of anti-RBD IgG were measured after 1 month from full vaccination (median: 1432 binding antibody units/ml [BAU/ml]); subsequently, a steep decrease (7.4-fold decrease) in IgG levels was observed at 6 months (median: 194.3 BAU/ml), with a further 2.5-fold decrease at 9 months (median: 79.3 BAU/ml). Furthermore, the same data, when analyzed for sex, showed significant differences between male and female participants at both 1 and 9 months from vaccination, but not at 6 months.
Conclusion: Our results confirm the tendency of anti-RBD antibodies to decrease over time, also when extending the analysis up to 9 months, and highlight a better ability of the female sex to produce antibodies 1 month and 9 months after vaccination. Overall, these data, obtained in a wide population of HCWs, support the importance of having increased the vaccine doses.
Keywords: Anti-RBD IgG; BNT162b2; Health care workers; Humoral Response; SARS-CoV-2.
【저자키워드】 SARS-CoV-2, health care workers, BNT162b2, Humoral response, Anti-RBD IgG, 【초록키워드】 SARS-CoV-2, BNT162b2 vaccine, coronavirus, immune response, vaccination, Health care, Vaccines, antibody, spike glycoprotein, Sex, Immunoglobulin, HCWs, RBD, male, female, Health care worker, Analysis, binding antibody, Anti-RBD antibody, Support, acute respiratory syndrome, significant difference, second dose, These data, domain, doses, quantitative assay, decrease, highlight, highest, the S1 subunit, analyzed, the spike protein, the RBD, the vaccine, were measured, female participant, IgG level, 【제목키워드】 SARS-CoV-2, vaccination, IgG antibody, Health care worker, longitudinal, binding domain,