Abstract
Background and aims: Monitoring the immune response against SARS-CoV-2 is pivotal in the evaluation of long-term vaccine efficacy. Immunoglobulin G (IgG) antibodies represent an advisable tool to reach this goal, especially for the still poorly defined antibody trend induced by the new class of mRNA vaccines against SARS-CoV-2.
Materials and methods: Anti-Spike RBD IgG antibodies were monitored in a cohort of healthcare workers at CRO Aviano, National Cancer Institute, through MAGLUMI® chemiluminescence assay, at 1 and 4 months after full-schedule of BNT162b2 or mRNA-1273 vaccination.
Results: At 1 month after vaccination, 99.9% of 767 healthcare workers showed a reactive antibody response, which was inversely correlated with age, and positively associated with a previous history of COVID-19, and mRNA-1273 vaccination. Serological response was maintained in 99.6% of the 516 subjects monitored also at follow-up. An antibody decay from 559.8 AU/mL (IQR 359.7-845.7) to 92.7 AU/mL (IQR 65.1-148.6; p < 0.001) was observed, independently from age and sex.
Conclusion: Our data supported the ability of SARS-CoV-2 mRNA vaccines to induce at least a 4 months-lasting IgG response, even outside the rules of clinical trials. The antibody decay observed at follow-up suggested to deepen the immune response characterization to identify subjects with low anti-SARS-CoV-2 immunity possibly requiring a vaccination boost.
Keywords: Antibody decay; COVID-19; IgG antibodies; SARS-CoV-2; mRNA vaccination.
【저자키워드】 COVID-19, SARS-CoV-2, mRNA vaccination, IgG antibodies, Antibody decay, 【초록키워드】 IgG, mRNA vaccination, Efficacy, Vaccine, immune response, vaccination, Immunity, antibody, mRNA vaccine, mRNA-1273, Antibody Response, clinical trials, anti-SARS-CoV-2, healthcare worker, Cohort, Immunoglobulin G, age, monitoring, Follow-up, chemiluminescence, boost, IgG response, National Cancer Institute, subject, RBD IgG, material, reactive, defined, identify, supported, suggested, correlated, induce, age and sex, CRO, IQR, of BNT162b2, 【제목키워드】 vaccination, healthcare worker, Cohort, IgG antibody,