A recombinant receptor-binding domain in trimeric form generates protective immunity against SARS-CoV-2 infection in nonhuman primates

作者：Limin Yang, Deyu Tian, Jian-Bao Han, Wenhui Fan, Yuan Zhang, Yunlong Li, Wenqiang Sun, Yanqiu Wei, Xiaodong Tian, Dan-Dan Yu, Xiao-Li Feng, Gong Cheng, Yuhai Bi, Yong‐Tang Zheng, Wenjun Liu · 发表于：The Innovation · 年份：2021 · DOI：10.1016/j.xinn.2021.100140 · 被引用次数：26 · 研究领域：SARS-CoV-2 and COVID-19 Research、COVID-19 Clinical Research Studies、Influenza Virus Research Studies

A safe and effective vaccine is critical to combat the COVID-19 pandemic. Here, we developed a trimeric SARS-CoV-2 receptor-binding domain (RBD) subunit vaccine candidate that simulates the natural structure of the spike (S) trimer glycoprotein. Immunization with the RBD trimer-induced robust humoral and cellular immune responses, and a high level of neutralizing antibodies was maintained for at least 4.5 months. Moreover, the antibodies that were produced in response to the vaccine effectively cross-neutralized the SARS-CoV-2 501Y.V2 variant (B.1.351). Of note, when the vaccine-induced antibodies dropped to a sufficiently low level, only one boost quickly activated the anamnestic immune response, conferring full protection against a SARS-CoV-2 challenge in rhesus macaques without typical histopathological changes in the lung tissues. These results demonstrated that the SARS-CoV-2 RBD trimer vaccine candidate is highly immunogenic and safe, providing long-lasting, broad, and significant immunity protection in nonhuman primates, thereby offering an optimal vaccination strategy against COVID-19.