Reduced binding and neutralization of infection- and vaccine-induced antibodies to the B.1.351 (South African) SARS-CoV-2 variant

Edara, V. V.; Norwood, C.; Floyd, K.; Lai, L.; Davis-Gardner, M. E.; Hudson, W. H.; Mantus, G.; Nyhoff, L. E.; Adelman, M. W.; Fineman, R.; Patel, S.; Byram, R.; Gomes, D. N.; Michael, G.; Abdullahi, H.; Beydoun, N.; Panganiban, B.; McNair, N.; Hellmeister, K.; Pitts, J.; Winters, J.; Kleinhenz, J.; Usher, J.; O'Keefe, J. B.; Piantadosi, A.; Waggoner, J. J.; Babiker, A.; Stephens, D. S.; Anderson, E. J.; Edupuganti, S.; Rouphael, N.; Ahmed, R.; Wrammert, J.; Suthar, M. S.

doi:10.1101/2021.02.20.432046

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bioRxiv · 10.1101/2021.02.20.432046

Reduced binding and neutralization of infection- and vaccine-induced antibodies to the B.1.351 (South African) SARS-CoV-2 variant

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Abstract

The emergence of SARS-CoV-2 variants with mutations in the spike protein is raising concerns about the efficacy of infection- or vaccine-induced antibodies to neutralize these variants. We compared antibody binding and live virus neutralization of sera from naturally infected and spike mRNA vaccinated individuals against a circulating SARS-CoV-2 B.1 variant and the emerging B.1.351 variant. In acutely-infected (5-19 days post-symptom onset), convalescent COVID-19 individuals (through 8 months post-symptom onset) and mRNA-1273 vaccinated individuals (day 14 post-second dose), we observed an average 4.3-fold reduction in antibody titers to the B.1.351-derived receptor binding domain of the spike protein and an average 3.5-fold reduction in neutralizing antibody titers to the SARS-CoV-2 B.1.351 variant as compared to the B.1 variant (spike D614G). However, most acute and convalescent sera from infected and all vaccinated individuals neutralize the SARS-CoV-2 B.1.351 variant, suggesting that protective immunity is retained against COVID-19.

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Edara, V. V., Norwood, C., Floyd, K., Lai, L., Davis-Gardner, M. E., Hudson, W. H., Mantus, G., Nyhoff, L. E., Adelman, M. W., Fineman, R., Patel, S., Byram, R., Gomes, D. N., Michael, G., Abdullahi, H., Beydoun, N., Panganiban, B., McNair, N., Hellmeister, K., Pitts, J., Winters, J., Kleinhenz, J., Usher, J., O'Keefe, J. B., Piantadosi, A., Waggoner, J. J., Babiker, A., Stephens, D. S., Anderson, E. J., Edupuganti, S., Rouphael, N., Ahmed, R., Wrammert, J., Suthar, M. S.. 2021-02-22. Reduced binding and neutralization of infection- and vaccine-induced antibodies to the B.1.351 (South African) SARS-CoV-2 variant. https://doi.org/10.1101/2021.02.20.432046

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