Geropeppa Maria, Papadatou Ioanna, Sarantis Panagiotis, Tzanoudaki Marianna, Ntanasis-Stathopoulos Ioannis, Bagratuni Tina, Terpos Evangelos, Spoulou Vana
Immunobiology and Vaccinology Research Laboratory, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece.
First Department of Pediatrics, School of Medicine, "Aghia Sophia" Children's Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece.
Vaccines (Basel). 2023 Jun 25;11(7):1148. doi: 10.3390/vaccines11071148.
mRNA vaccines have been instrumental in controlling the SARS-CoV-2 pandemic, but the short-lived protection mediated by Receptor Binding Domain (RBD)-specific antibodies necessitates frequent revaccinations to enhance vaccine-induced immunity. The development of RBD-specific B cell memory is critical for improving the qualitative and quantitative characteristics of the immune response. However, the effect of additional doses of mRNA vaccines on the composition of the RBD-specific B cell memory pool remains unclear. In this study, we found that dual BNT162b2 vaccination significantly increased both total RBD-specific and memory RBD-specific B cells and neutralizing antibodies. Following the second BNT162b2 dose, we showed a trend for the enrichment of CD27+IgM- memory RBD-specific B cells, which are known to correlate with a strong humoral response upon re-challenge. Repeated Measures Correlation (rmcorr) analysis revealed a significant correlation between antibody titers and both total and memory RBD-specific B cells, demonstrating that B cell and antibody responses are generated in a coordinated manner following BNT162b2 mRNA immunization. Our findings indicate that additional doses of the BNT162b2 mRNA vaccine enhance the qualitative and quantitative enrichment of the memory B cell pool against the vaccine antigens and collectively demonstrate the induction of a coordinated immune response to mRNA vaccination.
信使核糖核酸（mRNA）疫苗在控制新冠病毒大流行中发挥了重要作用，但由受体结合域（RBD）特异性抗体介导的短暂保护作用需要频繁加强接种以增强疫苗诱导的免疫力。RBD特异性B细胞记忆的形成对于改善免疫反应的质量和数量特征至关重要。然而，额外剂量的mRNA疫苗对RBD特异性B细胞记忆库组成的影响仍不清楚。在本研究中，我们发现两剂BNT162b2疫苗接种显著增加了RBD特异性B细胞总数和记忆性RBD特异性B细胞以及中和抗体。在第二剂BNT162b2接种后，我们发现CD27+IgM-记忆性RBD特异性B细胞有富集趋势，已知这些细胞与再次激发时强烈的体液反应相关。重复测量相关性（rmcorr）分析显示抗体滴度与RBD特异性B细胞总数和记忆细胞之间存在显著相关性，表明在BNT162b2 mRNA免疫后B细胞和抗体反应是以协调方式产生的。我们的研究结果表明，额外剂量的BNT162b2 mRNA疫苗可增强针对疫苗抗原的记忆B细胞库在质量和数量上的富集，并共同证明了对mRNA疫苗接种诱导的协调免疫反应。
