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bioRxiv · 10.1101/2022.01.25.477770

Vaccine-elicited murine antibody WS6 neutralizes diverse beta-coronaviruses by recognizing a helical stem supersite of vulnerability

Abstract

Immunization with SARS-CoV-2 spike elicits diverse antibodies, but can any of these neutralize broadly? Here, we report the isolation and characterization of antibody WS6, from a mouse immunized with mRNA encoding the SARS-CoV-2 spike. WS6 bound diverse beta-coronavirus spikes and neutralized SARS-CoV-2 variants, SARS-CoV, and related sarbecoviruses. Epitope mapping revealed WS6 to target a region in the S2 subunit, which was conserved among SARS-CoV-2, MERS-CoV, and hCoV-OC43. The crystal structure at 2-[A] resolution of WS6 with its S2 epitope revealed recognition to center on a conserved helix, which was occluded in both prefusion and post-fusion spike conformations. Structural and neutralization analyses indicated WS6 to neutralize by inhibiting fusion, post-viral attachment. Comparison of WS6 to other antibodies recently identified from convalescent donors or mice immunized with diverse spikes indicated a stem-helical supersite - centered on hydrophobic residues Phe1148, Leu1152, Tyr1155, and Phe1156 - to be a promising target for vaccine design. HighlightsO_LISARS-CoV-2 spike mRNA-immunized mouse elicited an antibody, WS6, that cross reacts with spikes of diverse human and bat beta-coronaviruses C_LIO_LIWS6 neutralizes SARS-CoV-2 variants, SARS-CoV, and related viruses C_LIO_LICrystal structure at 2-[A] resolution of WS6 in complex with a conserved S2 peptide reveals recognition of a helical epitope C_LIO_LIWS6 neutralizes by inhibition of fusion, post-viral attachment C_LIO_LIWS6 recognizes a supersite of vulnerability also recognized by other recently identified antibodies C_LIO_LIHelical supersite of vulnerability comprises a hydrophobic cluster spanning three helical turns, with acid residues framing the center turn C_LIO_LIGenetic and structural analysis indicate supersite recognition to be compatible with diverse antibody ontogenies C_LI

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BibTeXRIS

Shi, W., Wang, L., Zhou, T., Sastry, M., Yang, E. S., Zhang, Y., Chen, M., Chen, X., Choe, M., Creanga, A., Leung, K., Olia, A. S., Pegu, A., Rawi, R., Shen, C.-H., Stancofski, E.-S. D., Talana, C. A., Teng, I.-T., Wang, S., Corbett, K. S., Tsybovsky, Y., Mascola, J. R., Kwong, P. D.. 2022-01-26. Vaccine-elicited murine antibody WS6 neutralizes diverse beta-coronaviruses by recognizing a helical stem supersite of vulnerability. https://doi.org/10.1101/2022.01.25.477770

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