A mosaic-type trimeric RBD-based COVID-19 vaccine candidate induces potent neutralization against Omicron and other SARS-CoV-2 variants

Zhang, J.; Han, Z. B.; Liang, Y.; Zhang, X. F.; Jin, Y. Q.; Du, L. F.; Shao, S.; Wang, H.; Hou, J. W.; Xu, K.; Lei, Z. H.; Liu, Z. M.; Hou, Y. N.; Liu, N.; Shen, F. J.; Wu, J. J.; Zheng, X.; Li, X. Y.; Li, X.; Huang, W. J.; Wu, G. Z.; Su, J. G.; Li, Q. M.

doi:10.1101/2022.03.29.486173

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bioRxiv · 10.1101/2022.03.29.486173

A mosaic-type trimeric RBD-based COVID-19 vaccine candidate induces potent neutralization against Omicron and other SARS-CoV-2 variants

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Abstract

Large-scale populations in the world have been vaccinated with COVID-19 vaccines, however, breakthrough infections of SARS-CoV-2 are still growing rapidly due to the emergence of immune-evasive variants, especially Omicron. It is urgent to develop effective broad-spectrum vaccines to better control the pandemic of these variants. Here, we present a mosaic-type trimeric form of spike receptor-binding domain (mos-tri-RBD) as a broad-spectrum vaccine candidate, which carries the key mutations from Omicron and other circulating variants. Tests in rats showed that the designed mos-tri-RBD, whether used alone or as a booster shot, elicited potent cross-neutralizing antibodies against not only Omicron but also other immune-evasive variants. Neutralizing antibody titers induced by mos-tri-RBD were substantially higher than those elicited by homo-tri-RBD (containing homologous RBDs from prototype strain) or the inactivated vaccine BBIBP-CorV. Our study indicates that mos-tri-RBD is highly immunogenic, which may serve as a broad-spectrum vaccine candidate in combating SARS-CoV-2 variants including Omicron.

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Zhang, J., Han, Z. B., Liang, Y., Zhang, X. F., Jin, Y. Q., Du, L. F., Shao, S., Wang, H., Hou, J. W., Xu, K., Lei, Z. H., Liu, Z. M., Hou, Y. N., Liu, N., Shen, F. J., Wu, J. J., Zheng, X., Li, X. Y., Li, X., Huang, W. J., Wu, G. Z., Su, J. G., Li, Q. M.. 2022-03-29. A mosaic-type trimeric RBD-based COVID-19 vaccine candidate induces potent neutralization against Omicron and other SARS-CoV-2 variants. https://doi.org/10.1101/2022.03.29.486173

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