ABSTRACT
AIMS: Presence of anti-S1 region of SARS-CoV-2 spike protein was analysed, at two and eight months, in 477 immunocompetent healthcare workers in Zaragoza, Spain, vaccinated with mRNA-1273 (Moderna) or BNT162b2 (Pfizer). METHODS AND RESULTS: Antibody analysis was performed with Alinity i System (Abbott). At 2 months, 100% of vaccinated had anti-S1 IgG (mean = 13,285 AU ml-1 ). This value was significantly higher with Moderna (18,192 AU ml-1 ) than with Pfizer (10,441 AU ml-1 ). The mean value of anti-S1 IgG after vaccination was significantly higher in patients with than without previous infection (18,539 vs. 7919 AU ml-1 ); in both groups was significantly higher with Moderna than with Pfizer (21,881 vs. 15,733 AU ml-1 and 11,949 vs. 6387 AU ml-1 ), respectively. At 8 months, 100% of patients were IgG positive, with higher levels with Moderna than with Pfizer. Nevertheless, in ensemble of cases, a mean decrease of antibody levels of 11,025 AU ml-1 was observed. CONCLUSION: At 2 and 8 months after vaccination, IgG response persists with both vaccines but with important decrease which suggests the need for revaccination. SIGNIFICANCE AND IMPACT OF STUDY: The study contributes to know the immune status after vaccination with two of more used anti-SARS-CoV-2 vaccines. This knowledge is important for establishing the best vaccination strategy.
Subject(s)
COVID-19 Vaccines , COVID-19 , Immunity, Humoral , 2019-nCoV Vaccine mRNA-1273 , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Health Personnel , Humans , Immunoglobulin G , SARS-CoV-2 , Spain , Spike Glycoprotein, Coronavirus/immunology , VaccinationSubject(s)
2019-nCoV Vaccine mRNA-1273/administration & dosage , BNT162 Vaccine/administration & dosage , COVID-19 , Hematologic Neoplasms , SARS-CoV-2/immunology , Adult , Aged , Aged, 80 and over , COVID-19/immunology , COVID-19/mortality , COVID-19/prevention & control , Female , Hematologic Neoplasms/immunology , Hematologic Neoplasms/mortality , Humans , Male , Middle AgedABSTRACT
Several hundred millions of people have been diagnosed of coronavirus disease 2019 (COVID-19), causing millions of deaths and a high socioeconomic burden. SARS-CoV-2, the causative agent of COVID-19, induces both specific T- and B-cell responses, being antibodies against the virus detected a few days after infection. Passive immunization with hyperimmune plasma from convalescent patients has been proposed as a potentially useful treatment for COVID-19. Using an in-house quantitative ELISA test, we found that plasma from 177 convalescent donors contained IgG antibodies specific to the spike receptor-binding domain (RBD) of SARS-CoV-2, although at very different concentrations which correlated with previous disease severity and gender. Anti-RBD IgG plasma concentrations significantly correlated with the plasma viral neutralizing activity (VN) against SARS-CoV-2 in vitro. Similar results were found using an independent cohort of serum from 168 convalescent health workers. These results validate an in-house RBD IgG ELISA test in a large cohort of COVID-19 convalescent patients and indicate that plasma from all convalescent donors does not contain a high enough amount of anti-SARS-CoV-2-RBD neutralizing IgG to prevent SARS-CoV-2 infection in vitro. The use of quantitative anti-RBD IgG detection systems might help to predict the efficacy of the passive immunization using plasma from patients recovered from SARS-CoV-2.