Gobond Testing Technology (Beijing) Co., Ltd., Beijing, People's Republic of China.
Department of Science and Development, Beijing Youan Hospital, Capital Medical University, Beijing, People's Republic of China.
Emerg Microbes Infect. 2022 Dec;11(1):749-752. doi: 10.1080/22221751.2022.2044271.
The immunity potency upon natural infection or vaccination is the main concern for the vaccine strategy of severe acute respiratory syndrome coronavirus 2 (SARS COV-2 variant), especially the recently reported Omicron variant (B.1.1.529). In this study, 200 recipients immunized with three doses of a COVID-19-inactivated vaccine were enrolled, whose serum samples were collected within 2 months after the third immunization. The neutralizing activity of sera against the pseudotyped Omicron variant, prototype, and Delta variant was determined. Our results demonstrated that the positive neutralization activity was 95.5% for the Omicron variant, 99.5% for the prototype, and 98.5% for the Delta variant. The geometric mean titers (GMT) for the Omicron variant was 49 and maintained sustained immune levels for 2 months, which decreased by 4.9-fold and 3.0-fold compared with the prototype (GMT, 239) and Delta variant (GMT, 148), respectively. In summary, our study demonstrated that three doses of a COVID-19-inactivated vaccine effectively yielded potent cross-neutralizing activity against the Omicron variant at 2 months after the third vaccination.
在针对严重急性呼吸综合征冠状病毒 2 型（SARS-CoV-2 变体）的疫苗策略中，自然感染或接种疫苗后的免疫效力是主要关注点，特别是最近报告的奥密克戎变体（B.1.1.529）。在这项研究中，招募了 200 名接受三剂 COVID-19 灭活疫苗接种的受种者，在第三剂接种后 2 个月内采集了他们的血清样本。测定了血清对假型奥密克戎变体、原型和 Delta 变体的中和活性。我们的结果表明，奥密克戎变体的阳性中和活性为 95.5%，原型为 99.5%，Delta 变体为 98.5%。奥密克戎变体的几何平均滴度（GMT）为 49，在 2 个月内保持持续的免疫水平，与原型（GMT，239）和 Delta 变体（GMT，148）相比，分别下降了 4.9 倍和 3.0 倍。总之，我们的研究表明，三剂 COVID-19 灭活疫苗在第三剂接种后 2 个月内可有效产生针对奥密克戎变体的强效交叉中和活性。
