A Potential Novel COVID-19 Vaccine With RBD-HR1/HR2 Hexamer Structure

Liu, H.; Gao, X.; Wang, G.; Zhang, J.; Zhou, J.; Wei, T.; Zhang, Y.; Liu, Y.; Piao, J.; Zhang, Q.; Wang, Y.; Ma, X.; Zhu, X.; Rao, Y.; Xia, W.; Xie, H.; Zhang, W.

doi:10.1101/2021.10.28.465226

bioRxiv · 10.1101/2021.10.28.465226

A Potential Novel COVID-19 Vaccine With RBD-HR1/HR2 Hexamer Structure

Liu, H.·Gao, X.·Wang, G.·Zhang, J.·Zhou, J.·Wei, T.·Zhang, Y.·Liu, Y.·Piao, J.·Zhang, Q.·Wang, Y.·Ma, X.·Zhu, X.·Rao, Y.·Xia, W.·Xie, H.·Zhang, W.

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Abstract

The COVID-19 pandemic and the continued spreading of the SARS-CoV-2 variants have brought a grave public health consequence and severely devastated the global economy with recessions. Vaccination is considered as one of the most promising and efficient methods to end the COVID-19 pandemic and mitigate the disease conditions if infected. Although a few vaccines have been developed with an unprecedented speed, scientists around the world are continuing pursuing the best possible vaccines with innovations. Comparing to the expensive mRNA vaccines and attenuated/inactivated SARS-CoV-2 vaccines, recombinant protein vaccines have certain advantages, including their safety (non-virus components), potential stronger immunogenicity, broader protection, ease of scaling-up production, reduced cost, etc. In this study, we reported a novel COVID-19 vaccine generated with RBD-HR1/HR2 hexamer that was creatively fused with the RBD domain and heptad repeat 1 (HR1) or heptad repeat 2 (HR2) to form a dumbbell-shaped hexamer to target the spike S1 subunit. The novel hexamer COVID-19 vaccine induced high titers of neutralizing antibody in mouse studies (>100,000), and further experiments also showed that the vaccine also induced an alternative antibody to the HR1 region, which probably alleviated the drop of immunogenicity from the frequent mutations of SARS-CoV-2.

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Liu, H., Gao, X., Wang, G., Zhang, J., Zhou, J., Wei, T., Zhang, Y., Liu, Y., Piao, J., Zhang, Q., Wang, Y., Ma, X., Zhu, X., Rao, Y., Xia, W., Xie, H., Zhang, W.. 2021-10-29. A Potential Novel COVID-19 Vaccine With RBD-HR1/HR2 Hexamer Structure. https://doi.org/10.1101/2021.10.28.465226

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