Twelve-month specific IgG response to SARS-CoV-2 receptor-binding domain among COVID-19 convalescent plasma donors in Wuhan
Cesheng Li, Ding Yu, Xiao Wu, Liang Hong, Zhijun Zhou, Yong Xie, Taojing Li, Junzheng Wu, Fengping Lu, Lu Feng, Min Mao, Lianzhen Lin, Huanhuan Guo, Shenglan Yue, Feifei Wang, Yan Peng, Yong Hu, Zejun Wang, Jianhong Yu, Yong Zhang, Jia Lu, Haoran Ning, Huichuan Yang, Daoxing Fu, Yanlin He, Dongbo Zhou, Tao Du, Kai Duan, Demei Dong, Kun Deng, Xia Zou, Ya Zhang, Rong Zhou, Yang Gao, Xinxin Zhang, Xiaoming Yang
Abstract
To investigate the duration of humoral immune response in convalescent coronavirus disease 2019 (COVID-19) patients, we conduct a 12-month longitudinal study through collecting a total of 1,782 plasma samples from 869 convalescent plasma donors in Wuhan, China and test specific antibody responses. The results show that positive rate of IgG antibody against receptor-binding domain of spike protein (RBD-IgG) to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the COVID-19 convalescent plasma donors exceeded 70% for 12 months post diagnosis. The level of RBD-IgG decreases with time, with the titer stabilizing at 64.3% of the initial level by the 9th month. Moreover, male plasma donors produce more RBD-IgG than female, and age of the patients positively correlates with the RBD-IgG titer. A strong positive correlation between RBD-IgG and neutralizing antibody titers is also identified. These results facilitate our understanding of SARS-CoV-2-induced immune memory to promote vaccine and therapy development.