Hacker News Reader

Comment by solinent | Hacker News Reader

I remember at the start of this an infectious diseases professor commented how if you had the antibodies already against CoV you'd be fine, but if you had only half, you were at a significantly higher risk of death.

I guess the immune system can misidentify as well--I bet we haven't taxonomized everything fully yet so eventually we'll have a new name for what immunity is required.

View on HN

What a blatantly false statement. There is no sound scientific definition of "half" the antibodies.

Sorry can you rephrase?

What do you mean by half?

I have no clue! I just heard this a while back on some random video three months ago from an infectious diseases professor. My knowledge of biology is very low, I really shouldn't be speculating publically, I thought it was less controversial knowledge. I've probably just phrased it badly or remembered it in too simple of a manner due to my lack of background here.

I think half is a simplification, it must mean that if you have the wrong type or quantity or some combination thereof, but again I'm guessing and not an expert or even a professional.

The closest thing I can think of is https://en.wikipedia.org/wiki/Antibody-dependent_enhancement....

There's no way in which having real antibodies, but a reduced amount of them, would be worse than not having antibodies, but the following is very possible:

> It is likely that in older people the production of antibodies is slower and by the time the antibodies are developed in the titer that is sufficient to neutralize the virus, the virus changes its antigenic determinants. In this case, immuno-dominant neutralizing antibodies might start forming unstable complexes with the new form of the virus and start to infect monocytes/macrophages causing ADE. This process can trigger generalized infection of immune cells in multiple organs and cytokine storm

It's possibly by type and not mass, ie, one of each type of antibody versus various strains of COVID. I think that would make the most sense to me given the conclusion--if you don't have the right antibodies but have some you may be more susceptible to some strains and less susceptible to other strains. I will see if I get the time to find the original source.

Yeah that still doesn't make sense haha. It's not really a different strains thing. But if you read about ADE you'll see that, I don't understand it perfectly but more or less you have a partial match which seems to make the immune system turn on itself. (I butchered that but it's been a long day...)

Well it could be based on ADE--certain strains of coronavirus antibodies will help other strains replicate. In any case, I do remember quite clearly "half" but it was towards a very lay audience.

This statement as said is almost certainly false, it's too overly simplistic - half of what? Half of peak? Or do you mean only IgG but not IgM, etc?

But, related, and maybe what the professor was talking about:

https://en.wikipedia.org/wiki/Antibody-dependent_enhancement

^ This should be mandatory reading for anyone. Especially people that are obsessed with the idea that all vaccine candidates are inherently safe. (Unfortunately the term "anti-vaxxer" now gets thrown around for any actual legitimate discussion of the risks of untested vaccine candidates).

I'd note that ADE literally happens in Coronaviruses, so it's extra relevant. It can even happen outside the context of a vaccine, and may play a role in the pathology of severe SARS-CoV-2 infection.

Reply on news.ycombinator.com