A successful vaccination would represent the most efficient means to control the pandemic of Coronavirus Disease-19 (COVID-19) that led to millions of deaths worldwide. Novel mRNA-based vaccines confer protective immunity against SARS-CoV-2, but whether immunity is immediately effective and how long it will remain in recipients are uncertain. We sought to assess the effectiveness of a two-dose regimen since the boosts are often delayed concerning the recommended intervals. Methods A longitudinal cohort of healthcare workers (HCW, N = 46; 30.4% men; 69.6% women; mean age 36.05 ± 2.2 years) with no SARS-CoV-2 infection as documented by negative polymerase chain reaction was immunophenotyped in PBMC once a week for 4 weeks from the prime immunization (Pfizer mRNA BNT162b2) and had received 2 doses, to study the kinetic response. Results We identified three risk groups to develop SARS-CoV-2 infection IgG + -based (late responders, R – ; early responders, R + ; pauci responders, PR). In all receipts, amplification of B cells and NK cells, including IL4-producing B cells and IL4-producing CD8 + T cells, is early stimulated by the vaccine. After the boost, we observed a growing increase of NK cells but a resistance of T cells, IFNγ-producing CD4 + T cells, and IFNγ-producing NK cells. Also, hematologic parameters decline until the boost. The positive association of IFNγ-producing NK with IFNγ-producing CD4 + T cells by the multiple mixed-effect model, adjusted for confounders (p = 0.036) as well as the correlation matrix (r = 0.6, p < 0.01), suggests a relationship between these two subsets of lymphocytes. Conclusions These findings introduce several concerns about policy delay in vaccination: based on immunological protection, B cells and the persistent increase of NK cells during 2 doses of the mRNA-based vaccine could provide further immune protection against the virus, while CD8 + T cells increased slightly only in the R + and PR groups.
【저자키워드】 SARS-CoV-2, immune response, NK, Vaccines, CD4, CD8, 【초록키워드】 COVID-19, IgG, vaccination, pandemic, Lymphocytes, Immunity, T cells, SARS-COV-2 infection, NK cell, NK cells, risk, virus, healthcare worker, B cell, Pfizer, amplification, Cohort, T cell, protective immunity, Effectiveness, death, PBMC, age, novel, correlation, group, boost, mRNA BNT162b2, immune protection, association, dose, kinetic, HCW, responders, doses, hematologic, positive, recipient, intervals, mRNA-based vaccine, parameter, two-dose regimen, confounder, effective, prime immunization, immunological protection, polymerase chain, stimulated, Result, develop, adjusted, groups, the vaccine, subset, concerning,