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Epitope-resolved profiling of the SARS-CoV-2 Ab response identifies cross-reactivity with endemic human CoVs
“...SARS-CoV-2 (immune) response appears to be shaped by previous CoV exposures which have the potential to raise broadly neutralizing responses” https://www.cell.com/cell-reports-medicine/fulltext/S2666-3791(20)30244-5
“...SARS-CoV-2 (immune) response appears to be shaped by previous CoV exposures which have the potential to raise broadly neutralizing responses” https://www.cell.com/cell-reports-medicine/fulltext/S2666-3791(20)30244-5
Note that there are several papers showing pre-existing T-cell responses in pre-pandemic donors & that recognition sites in SARS-CoV-2 are shared with homologous sites in endemic (common cold causing) coronaviruses. Analogous findings in antibodies are unsurprising but cool.
Bottom line is, taken with T-cell findings there’s good evidence of population-wide prior immunity. It’s debatable what fraction of the population had functional immunity but I find compelling the suggestion that it was a substantial proportion & that this varied geographically.
I will say, revisiting some of the literature, it’s not a uniform finding that there are unequivocal, shared T-cell epitopes between common cold producing coronaviruses & SARS-COV-2. Some do, however, as here: https://www.nih.gov/news-events/nih-research-matters/immune-cells-common-cold-may-recognize-sars-cov-2
Here’s one that does support that claim to the origin of prior immunity, while maintaining that such prior immunity exists. It’s a really good paper! Le Bert, et al (2020). https://www.nature.com/articles/s41586-020-2550-z
What this truly brilliant paper shows is that there are numerous, different peptides, short pieces of the SARS-CoV-2 virus, which give rise to T-memory cells. These are in common to T-cells from SARS survivors 17y ago, suggestive of LONG LIVED immunity to SARS-CoV-2.
The reason I get cross with pseudoscience BS about variants “escaping immunity” is in this paper. There are so many different nucleocapsid peptide epitopes recognised by our memory T-cells that’s there’s no chance that small alterations from variants escaping recognition.
I wonder if spike may not have been the optimal target for vaccines. Not my field, and it is 20/20 hindsight, but I’d choose nucleocapsid sequences recognised from both SARS & SARS-CoV-2 due to evidence of durability. Ideally of course, you use whole virus, no guessing needed!
