"To determine whether 501Y.V2 is still recognized by non-neutralizing antibodies, the binding of polyclonal sera (from Fig.2a) to a recombinant 501Y.V2 RBD+SBD1 protein and an RBD+SBD1 from the original lineage was assessed by ELISA (Fig.2b). These data revealed that binding of polyclonal plasma to 501Y.V2 RBD+SBD1 was only substantially affected in a minority of cases (14 of 44 with ≥five-fold reduction, 32%). Most of the convalescent plasma/serum suffered less than four-fold reductions in total binding activity (as measured by area under the curve), suggesting a considerable non-neutralizing antibody component are still able to bind the 501Y.V2 spike antigen"

"On 7 January 2021 it was reported that Pfizer researchers had found the Pfizer and BioNTech COVID-19 vaccine in tests involving 20 blood assays to be capable of affording protection against one of the 501.V2 variant mutations (N501Y, shared with variant B1.1.7). Further investigation was to be undertaken to ascertain the level of protection involved."

https://en.wikipedia.org/wiki/501.V2_variant

Which came from this article.

https://www.theguardian.com/world/2021/jan/08/pfizer-vaccine...

But I can't find the original or subsequent studies.

1) it's in the spike protein. I think it's in the area that typically elicits antigen response. That's super bad news. If you look carefully, it's near the cleft of a representative antibody (fig 1a), and the buried surface area is high across the board on (clinically?) sampled antibodies (fig 1e), suggesting its importance.

2) it's a mutation that changes the charge state of one of the amino acid residues. E->K, changes a negative charge to a positive charge, potentially very bad if typically antibodies have a positive surface charge to interact with it, now they will be repelled. Since individual humans make random antibodies, even if there is no charge interaction, K amino acid is bigger than E, and so there is likely a shape interaction that could get disrupted by the "new bump" in the spike.

Is it a serious cause for concern? Yeah, almost certainly. The current round of vaccinations will probably be rendered inactive.

IMO the fastest way around this is to quickly approve a reformulation of the moderna/pfizer vaccines that encode for the new amino acid, or better yet, a cocktail of both.

For the more traditional protein-based vaccines, it could be more challenging, because the gut feeling is that an amino acid change like this could pose more of a risk to the effectiveness of the formulation for delivery of the vaccine (mrna is more "neutral" information medium that typically exerts less of a chemical change to the delivered product when altered).

In any case this emergent phenomenon will be certainly challenging to the regulatory landscape around vaccination.

disclaimer: I own MRNA stock.