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bioRxiv · 10.1101/2021.11.10.468037

Potent antibody immunity to SARS-CoV-2 variants elicited by a third dose of inactivated vaccine

Ju, B.·Zhou, B.·Song, S.·Fan, Q.·Ge, X.·Wang, H.·Cheng, L.·Guo, H.·Shu, D.·Liu, L.·Zhang, Z.
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Abstract

SARS-CoV-2 variants are still prevalent worldwide and continue to pose a challenge to the effectiveness of current vaccines. It remains unknown whether a third dose of inactivated vaccine elicits immune potential against SARS-CoV-2 variants. Here, we showed a significant decline in plasma neutralization against SARS-CoV-2 at seven months after a second dose of the inactivated vaccine in a large-scale cohort. However, we also found that a third vaccination with an inactivated vaccine largely increased plasma neutralization against variants including Beta, Delta, and Lambda. More importantly, the high-affinity anti-RBD memory B cells were also generated by the third vaccination, suggesting a more potent and longer protection. These findings highlighted the importance and effectiveness of a third dose of inactivated vaccine in conferring higher protection against the emerging variants in populations.

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Ju, B., Zhou, B., Song, S., Fan, Q., Ge, X., Wang, H., Cheng, L., Guo, H., Shu, D., Liu, L., Zhang, Z.. 2021-11-10. Potent antibody immunity to SARS-CoV-2 variants elicited by a third dose of inactivated vaccine. https://doi.org/10.1101/2021.11.10.468037

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