• FluTrackers.com Inc. does not provide medical advice. Information on this web site is collected from various internet resources, and the FluTrackers board of directors makes no warranty to the safety, efficacy, correctness or completeness of the information posted on this site by any author or poster. The information collated here is for instructional and/or discussion purposes only and is NOT intended to diagnose or treat any disease, illness, or other medical condition. Every individual reader or poster should seek advice from their personal physician/healthcare practitioner before considering or using any interventions that are discussed on this website. By continuing to access this website you agree to consult your personal physican before using any interventions posted on this website, and you agree to hold harmless FluTrackers.com Inc., the board of directors, the members, and all authors and posters for any effects from use of any medication, supplement, vitamin or other substance, device, intervention, etc. mentioned in posts on this website, or other internet venues referenced in posts on this website.
  • We are not asking for any donations. Do not donate to any entity who says they are raising funds for us.

Sci Transl Med . Nonstabilized SARS-CoV-2 spike mRNA vaccination induces broadly neutralizing antibodies in nonhuman primates

tetano

Editor, Senior Moderator
Sci Transl Med


. 2025 Jun 11;17(802):eadn5651.
doi: 10.1126/scitranslmed.adn5651. Epub 2025 Jun 11. Nonstabilized SARS-CoV-2 spike mRNA vaccination induces broadly neutralizing antibodies in nonhuman primates

R Dilshan Malewana[SUP] 1 2 [/SUP], Victoria Stalls[SUP] 1 3 [/SUP], Aaron May[SUP] 1 4 [/SUP], Xiaozhi Lu[SUP] 1 3 [/SUP], David R Martinez[SUP] 5 6 [/SUP], Alexandra Schäfer[SUP] 5 [/SUP], Dapeng Li[SUP] 1 3 [/SUP], Maggie Barr[SUP] 1 3 [/SUP], Laura L Sutherland[SUP] 1 3 [/SUP], Esther Lee[SUP] 1 3 [/SUP], Robert Parks[SUP] 1 3 [/SUP], Whitney Edwards Beck[SUP] 1 3 [/SUP], Amanda Newman[SUP] 1 3 [/SUP], Kevin W Bock[SUP] 7 [/SUP], Mahnaz Minai[SUP] 7 [/SUP], Bianca M Nagata[SUP] 7 [/SUP], C Todd DeMarco[SUP] 1 3 [/SUP], Thomas N Denny[SUP] 1 3 [/SUP], Thomas H Oguin 3rd[SUP] 1 3 [/SUP], Wes Rountree[SUP] 1 3 [/SUP], Yunfei Wang[SUP] 1 3 [/SUP], Katayoun Mansouri[SUP] 1 3 [/SUP], Robert J Edwards[SUP] 1 3 [/SUP], Lena Smith[SUP] 1 3 [/SUP], Gregory D Sempowski[SUP] 1 3 [/SUP], Amanda Eaton[SUP] 1 3 [/SUP], Hiromi Muramatsu[SUP] 8 [/SUP], Rory Henderson[SUP] 1 3 [/SUP], Ying Tam[SUP] 9 [/SUP], Christopher Barbosa[SUP] 9 [/SUP], Juanjie Tang[SUP] 10 [/SUP], Derek W Cain[SUP] 1 3 [/SUP], Sampa Santra[SUP] 11 [/SUP], Ian N Moore[SUP] 7 [/SUP], Hanne Andersen[SUP] 12 [/SUP], Mark G Lewis[SUP] 12 [/SUP], Hana Golding[SUP] 10 [/SUP], Robert Seder[SUP] 13 [/SUP], Surender Khurana[SUP] 10 [/SUP], David C Montefiori[SUP] 1 14 [/SUP], Norbert Pardi[SUP] 8 [/SUP], Drew Weissman[SUP] 15 [/SUP], Ralph S Baric[SUP] 5 [/SUP], Priyamvada Acharya[SUP] 1 4 14 [/SUP], Barton F Haynes[SUP] 1 2 3 [/SUP], Kevin O Saunders[SUP] 1 2 14 16 [/SUP]



Affiliations
Abstract

Immunization with messenger RNA (mRNA) or viral vectors encoding spike protein with diproline substitutions (S-2P) were shown to provide protective immunity, curbing the COVID-19 pandemic. However, in light of the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) that can cause COVID-19, it is essential that we understand how immunization with spike protein elicits neutralizing antibodies (nAbs). Here, we compared immunization of macaques with mRNA vaccines expressing ancestral spike protein with or without diproline substitutions, showing that the diproline substitutions were not required for protection against SARS-CoV-2 challenge or induction of broadly neutralizing B cell lineages. One group of nAbs elicited by the ancestral spike protein lacking diproline substitutions targeted the outer face of the receptor binding domain (RBD), neutralized all tested SARS-CoV-2 VOC pseudotyped viruses including Omicron XBB.1.5 in vitro, but lacked cross-sarbecovirus neutralization. Structural analysis showed that the macaque nAbs that could broadly neutralize VOCs bound to the same epitope as a human nAb, DH1193. In contrast, vaccine-induced antibodies that targeted the RBD inner face neutralized multiple sarbecoviruses, protected mice from bat CoV RsSHC014 challenge, but lacked Omicron variant neutralization. Thus, ancestral SARS-CoV-2 spike mRNA vaccines lacking proline substitutions can induce B cell lineages binding to distinct RBD sites that either broadly neutralize animal and human sarbecoviruses or neutralize recent Omicron VOCs. Thus, the use of a nonstabilized spike protein design in some COVID-19 vaccines does not preclude the elicitation of broad sarbecovirus and broad VOC nAbs.


 
Back
Top Bottom