Interesting paper from colleagues in China, studying evolution of omicron in great detail. They find evidence for antigenic seniority, ie preferential boost of responses to original antigens encountered. In breakthrough in vaccinees, that is Wuhan wild type virus.
They select B cells binding to RBD, then sequenced Ig coding genes, then expressing these as monoclonals and test for neuts against a range of mutants to map the specific antibodies to a set of previously defined epitopes targeted by neutralising and non neutralising antibodies.
They show that breakthroughs of BA2, BA5 preferentially induce non neutralising antibodies and map the specific antibodies to a set of previously defined epitopes targeted by neutralising and non neutralising antibodies
They then go ahead to predict further escape mutations, and test those in pseudoviruses, showing that a handful of them can lead to full “ plasma escape” (note again: coronavac vaccinated)
They warn that this eventually may lead to complete escape variants with possibly more severe disease association as a concern, though there is evidence for the latter. They also conclude that broad spectrum vaccines will be needed
In all, a beautiful piece of work , technically challenging, and showing some in depth analysis of observations that had been done before. I do however think we need to be a bit carefull extrapolating this globally.
Important caveat: the paper does not describe any of the sample backgrounds: timing of vaccination, of infection, of boosters and of sampling in relation to all of these. That can make all the difference in the world. Questions: would you observe the same in a later time point?
Another caveat when interpreting the vaccination response: this was coronavac, in a few individuals. Known to induce comparatively low levels of neutralizing antibodies so less likely cross reactive neutralising antibodies.
I do wonder about “unprecedented accelerated evolution”. Is evolutionary rate omicron unusual, and/ or is it the scale of circulation that makes this visible. Sparking of lineages is not unique for omicron. We also saw that for delta 
in all, nice work, through provoking, but caution to extrapolate too widely.
Correction: there is NO evidence
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