Wei Peilan, Cai Ruoxi, Zhang Lu, Zhang Jingjun, Zhang Zhaoyong, Zhu Airu, Li Hai, Zhuang Zhen, Chen Lan, Chen Jiantao, Zhang Yuting, Xiong Xinyi, Qu Bin, Zhuo Jianfen, Tang Tian, Zhang Yuanyuan, Chen Lei, Zhong Qier, Lin Zhiwei, Xing Xindan, Li Fang, Hu Qingtao, Dai Jun, Shi Yongxia, Zhao Jingxian, Zhao Jincun, Wang Yanqun
State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, People's Republic of China.
Guangzhou National Laboratory, Guangzhou, People's Republic of China.
Emerg Microbes Infect. 2025 Dec;14(1):2459140. doi: 10.1080/22221751.2025.2459140. Epub 2025 Feb 7.
Neutralizing antibody titres have been shown to correlate with immune protection against COVID-19 and can be used to estimate vaccine effectiveness. Numerous studies have explored the relationship between neutralizing antibodies and protection. However, there remains a lack of quantitative data directly assessing the minimum effective protective neutralizing antibody titre in . In this study, we utilized eight cohorts of participants with diverse immune backgrounds for evaluation of protective antibody response. To precisely assess the lower threshold of neutralizing antibody titres required for effective protection against SARS-CoV-2 infections, we employed plasma adoptive transfer from different cohorts into mice. This study demonstrated that neutralizing titres in the plasma of recipient mice correlated well with those in human donors, and a positive linear correlation was observed between the human and mouse recipients of transferred plasma neutralizing titre. A pseudotyped virus neutralizing titres greater than 7 was identified as the minimum threshold necessary to reduce viral titres in infected mice, establishing a crucial baseline for effective protection. Furthermore, despite the variability in immune backgrounds, these diverse cohorts' plasma exhibited a similar neutralizing antibody threshold necessary for protection. This finding has significant implications for vaccine design and the assessment of immune competence.
中和抗体滴度已被证明与针对新冠病毒的免疫保护相关，可用于评估疫苗效力。众多研究探讨了中和抗体与保护作用之间的关系。然而，仍然缺乏直接评估有效保护所需的最低中和抗体滴度的定量数据。在本研究中，我们利用了八组具有不同免疫背景的参与者来评估保护性抗体反应。为了精确评估有效预防新冠病毒感染所需的中和抗体滴度的下限，我们将来自不同组的血浆过继转移到小鼠体内。本研究表明，受体小鼠血浆中的中和滴度与人类供体中的中和滴度高度相关，并且在转移血浆中和滴度的人类和小鼠受体之间观察到正线性相关。确定假型病毒中和滴度大于7是降低感染小鼠病毒滴度所需的最低阈值，为有效保护建立了关键基线。此外，尽管免疫背景存在差异，但这些不同组的血浆表现出相似的保护所需中和抗体阈值。这一发现对疫苗设计和免疫能力评估具有重要意义。
