摘要
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-2501Y.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 SARSCoV-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.
基金
This study was funded by National Key Technologies Research and Development Program grants 2018YFC1200600 and 2018YFC1200500 to L.M.Y.
a grant from Strategic Priority Research Program of the Chinese Academy of Sciences XDB29010000 to W.J.L.and XDB29010102 to Y.H.B.
the National Natural Science Foundation of China(NSFC)grants 32041010 and 31900155 to Y.H.B.
Youth Innovation Promotion Association of CAS grant 2017122 to Y.H.B.
