Forgacs David, Silva-Moraes Vanessa, Sautto Giuseppe A, Hanley Hannah B, Gattiker Jasper L, Jefferson Alexandria M, Kolhe Ravindra, Ross Ted M
Center for Vaccines and Immunology, University of Georgia, Athens, GA 30605, USA.
Department of Pathology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA.
Vaccines (Basel). 2022 Apr 29;10(5):696. doi: 10.3390/vaccines10050696.
In order to longitudinally track SARS-CoV-2 antibody levels after vaccination or infection, we assessed anti-RBD antibody levels in over 1000 people and found no significant decrease in antibody levels during the first 14 months after infection in unvaccinated participants, however, a significant waning of antibody levels was observed following vaccination. Participants who were pre-immune to SARS-CoV-2 prior to vaccination seroconverted to higher antibody levels, which were maintained at higher levels than in previously infected, unvaccinated participants. Older participants exhibited lower level of antibodies after vaccination, but a higher level after infection than younger people. The rate of antibody waning was not affected by pre-immunity or age. Participants who received a third dose of an mRNA vaccine not only increased their antibody levels ~14-fold, but also had ~3 times more antibodies compared to when they received their primary vaccine series. PBMC-derived memory B cells from 13 participants who lost all circulating antibodies were differentiated into antibody secreting cells (ASCs). There was a significant recall of memory B cell ASCs in the absence of serum antibodies in 5-8 of the 10 vaccinated participants, but not in any of the 3 infected participants, suggesting a strong connection between antibody levels and the effectiveness of memory B cell recall.
为了纵向追踪接种疫苗或感染后新型冠状病毒2（SARS-CoV-2）抗体水平，我们评估了1000多人的抗受体结合域（RBD）抗体水平，发现未接种疫苗的参与者在感染后的前14个月内抗体水平没有显著下降，然而，接种疫苗后观察到抗体水平显著下降。在接种疫苗前对SARS-CoV-2具有预免疫的参与者血清转化为更高的抗体水平，且这些抗体水平维持在高于先前感染但未接种疫苗的参与者的水平。年长的参与者接种疫苗后抗体水平较低，但感染后比年轻参与者的抗体水平更高。抗体下降速率不受预免疫或年龄的影响。接受第三剂mRNA疫苗的参与者不仅使抗体水平提高了约14倍，而且与接受初级疫苗系列时相比，抗体数量增加了约3倍。从13名失去所有循环抗体的参与者的外周血单核细胞（PBMC）中分离出的记忆B细胞分化为抗体分泌细胞（ASC）。在10名接种疫苗的参与者中，有5 - 8名在没有血清抗体的情况下出现了记忆B细胞ASC的显著召回，但在3名感染参与者中均未出现，这表明抗体水平与记忆B细胞召回的有效性之间存在紧密联系。
