Impaired Cellular Immunity to SARS-CoV-2 in Severe COVID-19 Patients
Ling Ni, Meng‐Li Cheng, Feng Yu, Hui Zhao, Jingyuan Liu, Fang Ye, Qing Ye, Gengzhen Zhu, Xiaoli Li, Pengzhi Wang, Jing Shao, Yong‐Qiang Deng, Wei Peng, Fang Chen, Cheng‐Feng Qin, Guoqing Wang, Fan Li, Hui Zeng, Chen Dong
Abstract
The high infection rate and rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) make it a world-wide pandemic. Individuals infected by the virus exhibited different degrees of symptoms, and most convalescent individuals have been shown to develop both cellular and humoral immune responses. However, virus-specific adaptive immune responses in severe patients during acute phase have not been thoroughly studied. Here, we found that in a group of COVID-19 patients with acute respiratory distress syndrome (ARDS) during hospitalization, most of them mounted SARS-CoV-2-specific antibody responses, including neutralizing antibodies. However, compared to healthy controls, the percentages and absolute numbers of both NK cells and CD8 + T cells were significantly reduced, with decreased IFNγ expression in CD4 + T cells in peripheral blood from severe patients. Most notably, their peripheral blood lymphocytes failed in producing IFNγ against viral proteins. Thus, severe COVID-19 patients at acute infection stage developed SARS-CoV-2-specific antibody responses but were impaired in cellular immunity, which emphasizes on the role of cellular immunity in COVID-19.