501Y.V2 and 501Y.V3 variants of SARS-CoV-2 lose binding to Bamlanivimab in vitro

Liu, H.; Wei, P.; Zhang, Q.; Chen, Z.; Aviszus, K.; Downing, W.; Peterson, S.; Reynoso, L.; Downey, G.; Frankel, S.; Kappler, J.; Marrack, P.; Zhang, G.

doi:10.1101/2021.02.16.431305

bioRxiv · 10.1101/2021.02.16.431305

501Y.V2 and 501Y.V3 variants of SARS-CoV-2 lose binding to Bamlanivimab in vitro

Liu, H.·Wei, P.·Zhang, Q.·Chen, Z.·Aviszus, K.·Downing, W.·Peterson, S.·Reynoso, L.·Downey, G.·Frankel, S.·Kappler, J.·Marrack, P.·Zhang, G.

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Abstract

We generated several versions of the receptor binding domain (RBD) of the Spike protein with mutations existing within newly emerging variants from South Africa and Brazil. We found that the mutant RBD with K417N, E484K, and N501Y exchanges has higher binding affinity to the human receptor compared to the wildtype RBD. This mutated version of RBD also completely abolishes the binding to a therapeutic antibody, Bamlanivimab, in vitro.

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Liu, H., Wei, P., Zhang, Q., Chen, Z., Aviszus, K., Downing, W., Peterson, S., Reynoso, L., Downey, G., Frankel, S., Kappler, J., Marrack, P., Zhang, G.. 2021-02-16. 501Y.V2 and 501Y.V3 variants of SARS-CoV-2 lose binding to Bamlanivimab in vitro. https://doi.org/10.1101/2021.02.16.431305

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