PT - JOURNAL ARTICLE AU - Daniel J. Sheward AU - Marco Mandolesi AU - Changil Kim AU - Leo Hanke AU - Laura Perez Vidakovics AU - Gerald McInerney AU - Gunilla B. Karlsson Hedestam AU - Ben Murrell TI - Driving potent neutralization of a SARS-CoV-2 Variant of Concern with a heterotypic boost AID - 10.1101/2021.04.03.438330 DP - 2021 Jan 01 TA - bioRxiv PG - 2021.04.03.438330 4099 - http://biorxiv.org/content/early/2021/04/05/2021.04.03.438330.short 4100 - http://biorxiv.org/content/early/2021/04/05/2021.04.03.438330.full AB - The emergence of SARS-CoV-2 Variants of Concern (VOCs) with mutations in key neutralizing antibody epitopes threatens to undermine vaccines developed against the pandemic founder variant (Wu-Hu-1). Widespread vaccine rollout and continued transmission are creating a population that has antibody responses of varying potency to Wu-Hu-1. Against this background, it is critical to assess the outcomes of subsequent booster vaccination with variant antigens. It is not yet known whether such heterotypic vaccine boosts would be compromised by original antigenic sin, where pre-existing responses to a prior variant dampen responses to a new one, or whether the primed memory B cell repertoire would bridge the gap between Wu-Hu-1 and VOCs. Here, we show that a single adjuvanted dose of receptor binding domain (RBD) protein from VOC 501Y.V2 (B.1.351) drives an extremely potent neutralizing antibody response capable of cross-neutralizing both Wu-Hu-1 and 501Y.V2 in rhesus macaques previously immunized with Wu-Hu-1 spike protein.Competing Interest StatementThe authors have declared no competing interest.