Thread by @BalazsLab

Our paper describing the potential for mRNA vaccines to induce antibodies capable of neutralizing many of the circulating variants is now available online at Cell!
cell.com/cell/fulltext/…

We created pseudoviruses representing many of the globally circulating variants, many containing numerous mutations in and around the receptor binding domain (RBD)

Using our previously described pseudovirus neutralization assay, we determined the potential for sera obtained from patients receiving one or two doses of the Pfizer (BNT162b2) or Moderna (mRNA-1273) vaccines.

We saw dose-dependent neutralization titers that correlated well with RBD-based ELISA values measuring binding.

Neutralization titers varied significantly across the pseudoviruses we tested. With P.1/P.2 and the B.1.351 lineages showing very significant differences in neutralization.

This neutralization resistance was largely a result of the mutations within the RBD region. When we reverted the RBD mutations alone, we recovered most of the neutralizing activity.

Our results suggest that antibody responses raised by the current vaccines may be impacted by the circulating variants. Of course, other aspects of the immune response could still keep vaccinated individuals from developing severe disease, we do not have enough data yet to know.

Many thanks to all of those in my lab @ragoninstitute and at @MGHPathology who worked very hard under very tight timelines to get all of this done! Special thanks to @wilfredo_nk , @EvanCLam, @kstdenis29, @NaranbhaiVivek and the @SchmidtLabHMS for all their help!