Clinical City Hospital named after I.V. Davydovsky, Moscow Department of Healthcare, Moscow, Russia;
Federal State Budget Institution National Research Centre for Epidemiology and Microbiology named after Honorary Academician N.F. Gamaleya of the Ministry of Health of the Russian Federation, Moscow, Russia.
J Immunol. 2022 Mar 1;208(5):1139-1145. doi: 10.4049/jimmunol.2101052. Epub 2022 Jan 31.
Despite measures taken world-wide, the coronavirus disease 2019 (COVID-19) pandemic continues. Because efficient antiviral drugs are not yet widely available, vaccination is the best option to control the infection rate. Although this option is obvious in the case of COVID-19-naive individuals, it is still unclear when individuals who have recovered from a previous SARS-CoV-2 infection should be vaccinated and whether the vaccination raises immune responses against the coronavirus and its novel variants. In this study, we collected peripheral blood from 84 healthy human donors of different COVID-19 status who were vaccinated with the Sputnik Light vaccine and measured the dynamics of the Ab and T cell responses, as well as the virus-neutralizing activity (VNA) in serum, against two SARS-CoV-2 variants, B.1.1.1 and B.1.617.2. We showed that vaccination of individuals previously exposed to the virus considerably boosts the existing immune response. In these individuals, receptor-binding domain (RBD)-specific IgG titers and VNA in serum were already elevated on the 7th day after vaccination, whereas COVID-19-naive individuals developed the Ab response and VNA mainly 21 d postvaccination. Additionally, we found a strong correlation between RBD-specific IgG titers and VNA in serum, and according to these data vaccination may be recommended when the RBD-specific IgG titers drop to 142.7 binding Ab units/ml or below. In summary, the results of the study demonstrate that vaccination is beneficial for both COVID-19-naive and recovered individuals, especially since it raises serum VNA against the B.1.617.2 variant, one of the five SARS-CoV-2 variants of concern.
尽管全球范围内采取了措施，但 2019 年冠状病毒病（COVID-19）大流行仍在继续。由于目前还没有广泛可用的高效抗病毒药物，接种疫苗是控制感染率的最佳选择。虽然对于从未感染过 COVID-19 的个体来说，这个选择是显而易见的，但对于从前感染过 SARS-CoV-2 的个体，何时应该接种疫苗以及接种疫苗是否会引起针对冠状病毒及其新型变体的免疫反应，目前还不清楚。在这项研究中，我们收集了来自 84 名不同 COVID-19 状态的健康人类供体的外周血，这些供体接种了 Sputnik Light 疫苗，并测量了针对两种 SARS-CoV-2 变体 B.1.1.1 和 B.1.617.2 的 Ab 和 T 细胞反应以及血清中的病毒中和活性（VNA）的动态变化。我们表明，对先前接触过病毒的个体进行疫苗接种可以大大增强现有的免疫反应。在这些个体中，疫苗接种后第 7 天，血清中的受体结合域（RBD）特异性 IgG 滴度和 VNA 已经升高，而 COVID-19 未感染的个体主要在接种疫苗后 21 天产生 Ab 反应和 VNA。此外，我们发现 RBD 特异性 IgG 滴度与血清中的 VNA 之间存在很强的相关性，根据这些数据，当 RBD 特异性 IgG 滴度降至 142.7 个结合 Ab 单位/ml 或以下时，可能推荐接种疫苗。总之，研究结果表明，接种疫苗对 COVID-19 未感染和已康复的个体都有益，尤其是因为它可以提高针对 B.1.617.2 变体的血清 VNA，B.1.617.2 是五个关注的 SARS-CoV-2 变体之一。
