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bioRxiv · 10.1101/2021.05.16.444369

Broad neutralization against SARS-CoV-2 variants induced by a modified B.1.351 protein-based COVID-19 vaccine candidate

Abstract

Beginning in late 2020, the emergence and spread of multiple variant SARS-CoV-2 strains harboring mutations which may enable immune escape necessitates the rapid evaluation of second generation COVID-19 vaccines, with the goal of inducing optimized immune responses that are broadly protective. Here we demonstrate in a mouse immunogenicity study that two doses of a modified B.1.351 spike (S)-Trimer vaccine (B.1.351 S-Trimer) candidate can induce strong humoral immune responses that can broadly neutralize both the original SARS-CoV-2 strain (Wuhan-Hu-1) and Variants of Concern (VOCs), including the UK variant (B.1.1.7), South African variant (B.1.351) and Brazil variant (P.1). Furthermore, while immunization with two doses (prime-boost) of Prototype S-Trimer vaccine (based on the original SARS-CoV-2 strain) induced lower levels of cross-reactive neutralization against the B.1.351 variant, a third dose (booster) administered with either Prototype S-Trimer or B.1.351 S-Trimer was able to increase neutralizing antibody titers against B.1.351 to levels comparable to neutralizing antibody titers against the original strain elicited by two doses of Prototype S-Trimer.

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BibTeXRIS

Su, D., Li, X., He, C., Huang, X., Chen, M., Wang, Q., Qin, W., Liang, Y., Xu, R., Wu, J., Luo, P., Yang, X., Zeng, Y., Luo, M., Luo, D., Salisbury, D. M., Ambrosino, D., Siber, G., Clemens, R., Liang, P., Liang, J. G.. 2021-05-17. Broad neutralization against SARS-CoV-2 variants induced by a modified B.1.351 protein-based COVID-19 vaccine candidate. https://doi.org/10.1101/2021.05.16.444369

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