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0 pointsanonuser1234564y ago0 comments

Right, but it is harder for an organism to make multiple adaptations at once. Natural infection produces antibodies that target the spike protein as well as other sites. To evade immunity, the virus would need to change both sites.

It is very clear that the vaccine is putting selective pressure on spike protein evolution. Having alternative targets makes it harder to escape.

We currently don’t know if those other sites are beneficial or not. Sometimes they can even be counter productive (ADE, but we don’t really see that yet?)

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ithkuil4y ago· 2 in thread

(genuine question) What does prevent us from creating mRNA vaccines that target multiple sites and not only the spike protein?

raphlinus4y ago

https://theconversation.com/covid-vaccines-focus-on-the-spik... is probably relevant to your question. The short answer (this was also discussed recently on TWiV) is that spike is the earliest interaction with cells, so focusing on it hopefully causes the immune response to mount earlier as well. But, as described in the link, other proteins may be viable targets as well.

anonuser123456OP4y ago

Another issue is, other targets may not provide neutralizing immunity and may facilitate ADE. I don't think we've seen ADE in natural infection yet, so it may just be a theoretical issue, but I also don't know if we've really looked for ADE in natural infection either.

We do know that other similar coronavirus vaccine candidates (a candidate for SARS-COV-1) exhibited ADE in primate studies. So since the spike protein appears effective currently, maybe it's best to stick with that.

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