D614G Spike Variant Does Not Alter IgG, IgM, or IgA Spike Seroassay Performance

Klumpp-Thomas, C.; Kalish, H.; Hicks, J.; Mehalko, J.; Drew, M.; Memoli, M. J.; Hall, M. D.; Esposito, D.; Sadtler, K.

Emergence of a new variant of spike protein (D614G) with increased infectivity and transmissibility has prompted many to analyze the potential role of this variant in the SARS-CoV-2 pandemic. When a new variant emerges, there is a concern regarding whether an individual exposed to one variant of a virus will have cross-reactive immune memory to the second variant. Accordingly, we analyzed the serologic reactivity of D614 (original) and G614 variant spike proteins. We found that antibodies from a high-incidence population in New York City reacted both toward the original D614 spike and the G614 spike variant. These data suggest that patients who have been exposed to either SARS-CoV-2 variant have humoral immunity that can respond against both variants. This is an important finding both for SARS-CoV-2 disease biology and for potential antibody-based therapeutics.