[HN Gopher] T cells recognize recent SARS-CoV-2 variants
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T cells recognize recent SARS-CoV-2 variants
Author : onetimemanytime
Score : 46 points
Date : 2021-03-31 20:05 UTC (2 hours ago)
(HTM) web link (www.nih.gov)
(TXT) w3m dump (www.nih.gov)
| burlesona wrote:
| Sounds like good news.
|
| There's also this bit at the end:
|
| > Optimal immunity to SARS-Cov-2 likely requires strong
| multivalent T-cell responses in addition to neutralizing
| antibodies and other responses to protect against current SARS-
| CoV-2 strains and emerging variants, the authors indicate. They
| stress the importance of monitoring the breadth, magnitude and
| durability of the anti-SARS-CoV-2 T-cell responses in recovered
| and vaccinated individuals as part of any assessment to determine
| if booster vaccinations are needed.
|
| I haven't heard a lot of discussion around that, but it seems
| pretty logical to me that we'll continue to see substantial
| numbers of new variants for this virus, and thus there's a good
| chance we'll eventually need booster vaccinations to maintain
| immunity, unless (until?) we could get the whole planet
| vaccinated and eradicate the disease.
|
| But since eradication seems highly unlikely, I'm hoping that
| we'll find the basic vaccines we've come up with so far can be
| modified to target new variants much in the way we come up with a
| new flu shot every year and don't have to go through the same
| full approval and manufacturing ramp-up process.
| Trasmatta wrote:
| > But since eradication seems highly unlikely, I'm hoping that
| we'll find the basic vaccines we've come up with so far can be
| modified to target new variants
|
| My understanding is that one of the major benefits of mRNA
| vaccines is how easy they are to both design and produce
| (although storage and transportation is a challenge). It seems
| likely we might need yearly boosters, and I think the mRNA
| vaccines will be up to the task.
| AbortedLaunch wrote:
| An important, as of yet unresolved question, is whether those
| changed vaccines will lead to the generation of new
| antibodies vs. a boost of the existing ones, a phenomenon
| called original antigenic sin. Fingers crossed...
| yowlingcat wrote:
| This is my biggest worry. I can't help but wonder (with a
| very uneducated and uninformed opinion here) if we are
| stoking or entering the next stage of an arms race.
| tialaramex wrote:
| Eradication would have been the economically most sensible
| approach, but that was also true for elimination within the
| countries that would be paying for it - and it's not what they
| chose. Some of them apparently figured if you kill half a
| million of your people and "open up" your economy you can...
| offset the enormous cost of losing all those people by
| pretending they aren't dead? I honestly don't know, I suspect
| it'll turn out that nobody actually did any analysis, they just
| assumed if they can spout a talking point and have the numbers
| to push through the policy Mother Nature will have to go along
| with them, and er, nope.
|
| So I don't expect them to pursue eradication either once the
| immediate local threat from the pandemic recedes. There's no
| great commitment to eradication generally from these countries,
| the funding mostly comes from charitable donation, even though
| obviously disease eradication makes economic sense as an
| investment. How much money for example, did your government
| spend on global elimination efforts for Rinderpest? Or did it
| just say "Not our problem" the moment there was no disease in
| their own cattle?
| jsight wrote:
| I'm not seeing any evidence that eradication of a virus like
| this would have been at all likely, even with extreme
| measures.
| tialaramex wrote:
| If the virus has a viable non-human reservoir then
| eradication becomes very difficult and in some cases
| impossible. We likely cannot get rid of Influenza because
| viruses from that family thrive in a huge number of other
| mammals. So you'd be chasing it down in pigs, and in
| chickens, and it becomes an insurmountable challenge.
|
| But although this virus presumably originated in another
| mammal species (it is assumed to have once been a bat
| virus) it's not clear to me whether there's a real
| reservoir in other species today, the vast bulk of the
| world's infected seem to be humans.
|
| In a virus that lacks a viable animal reservoir you can
| achieve eradication by "just" eliminating the virus in
| humans in each place and ensuring infected humans don't
| spread it into places where it was eliminated, a strategy
| that costs money but is final. That's where the previous
| SARS virus went - we eliminated it and it didn't come back,
| and of course it's why Smallpox is gone.
|
| And eliminating SARS-CoV-2 is possible, because New Zealand
| did it. They had outbreaks in elderly care a year ago, and
| they locked down, tracked down every case, isolated every
| infected person, and eliminated the virus. All subsequent
| outbreaks have been connected to their border, if everybody
| had done likewise the virus would be gone. Of course that
| wasn't entirely realistic (other large islands like Great
| Britain could definitely have at least attempted this but
| they did not, but it's difficult to imagine North America
| or Russia achieving elimination without a vaccine) but with
| better tools now I think it could be attempted if the
| political existed, which I argue it does not.
|
| The trickiest part about this virus for elimination from
| 2022 onward is maybe it's viable as a virus that doesn't
| cause much disease, especially in a vaccinated population.
| If it's infecting otherwise healthy adults and just causing
| sniffles for a week, once the pandemic headlines stop
| nobody will isolate and prevent onward spread. In much of
| the world (including the US) they'll even keep going to
| work and give it to colleagues as well as those they live
| with. Lots of coronaviruses thrive this way in humans.
| rootusrootus wrote:
| > much in the way we come up with a new flu shot every year
|
| I'm hoping that since it is a coronavirus, and not influenza,
| it won't mutate anywhere near fast enough to evade vaccines on
| a yearly basis. Right now SARS-CoV-2 is getting a best case
| environment for mutation. When a substantial portion of the
| world has been vaccinated, the mutation rate is going to drop
| significantly, and hopefully with perhaps one more iteration of
| the vaccine (given to the whole world, granted) we can dispense
| with this virus altogether.
| mmebane wrote:
| Another recent study [1], discussed on This Week in Virology [2],
| also found T-cell immunity to be robust against mutations.
| However, there seems to be an open question of how well natural T
| cells, trained on the whole virus, will compare to T cells
| trained on vaccines that only have the spike protein or some
| other subset.
|
| [1]: https://www.biorxiv.org/content/10.1101/2021.02.27.433180v1
| [2]: https://www.microbe.tv/twiv/twiv-736/
| jonny_eh wrote:
| I recall reading that the enhanced immune response from the
| vaccines were more protective than a natural infection.
| dragontamer wrote:
| Why is this post downvoted?
|
| I know that P.1 (Brazil variant) seems to totally avoid
| natural immunity. The proof is from the city of Manaus, which
| was over 75% infected in October 2020. A resurgent wave of
| COVID19 hit in January 2021.
|
| At first, this didn't seem possible. But upon further study,
| it seemed that P.1 was avoiding natural immunity. So its
| reinfecting a ton of people in Manaus.
|
| ------------
|
| In contrast, the Pfizer vaccine has shown to confer immunity
| to both the original strain AND to P.1. As such, the immune
| response created from Pfizer absolutely offers better
| protection, once we account for the variants (especially P.1
| and B.1.351, which both have defenses against natural
| immunity)
|
| B.1.351 is the other "immune avoiding" variant. And I await
| for more studies before making a conclusion on that matter.
|
| --------
|
| EDIT: It seems like the article is discussing B.1.351 among
| its list of variants. That's good: the South African strain
| seemed like it had some ability to avoid our immune system,
| but our T-cells are still functioning against it. So a P.1 /
| Manaus event probably won't happen.
| timr wrote:
| > I know that P.1 (Brazil variant) seems to totally avoid
| natural immunity.
|
| This is completely false, and is a poor extrapolation from
| a faulty initial data point. There have now been several
| publications -- including the J&J clinical trial data
| itself [1] -- which show that immune responses induced by
| non-variant virus or vaccine are protective against the
| Brazilian variant.
|
| > The proof is from the city of Manaus, which was over 75%
| infected in October 2020.
|
| This number is based on a study that was published in
| Nature in summer 2020, and used a number of questionable
| "adjustments" to the raw seroprevalence data to arrive at
| their conclusion.
|
| The parsimonious conclusion is that the paper citing 75%
| seroprevalence in Manaus was wrong.
|
| [1] https://www.ucsf.edu/news/2021/03/420071/how-effective-
| johns...
| anonuser123456 wrote:
| >The proof is from the city of Manaus,
|
| The Manaus data was not very compelling. Lots of selection
| bias in their sampling.
| dragontamer wrote:
| There's multiple studies and multiple sets of data from
| Manaus. You'll have to be more specific. Which data, from
| which study, is untrustworthy?
| anonuser123456 wrote:
| I do not have the citation handy, but in one study, they
| recruited individuals by enticing them with the results;
| e.g. if you take take part in the study, we will give you
| the antibody result. This would obviously bias the
| results toward people that believed they had the virus,
| but didn't have a test when sick.
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