Clues to Covid-19 coronavirus’s vulnerability emerge from antibody against SARS

That go me too, but to be honest the title says it like it really is.

There are different antibodies being tested though. So there's a good chance a properly working mAb (not inducing Antibody Dependent Enhancement) will happen.

From the actual paper [0]:

Antibodies to this influenza HA trimeric interface epitope [that we studied before SARS-nCov-2 came along] do not exhibit in vitro neutralization activity but can confer in vivo protection. Similarly, antibodies to another conserved epitope that partially overlaps with the influenza HA trimeric interface also are non-neutralizing in vitro, but protective in vivo (26). Examples of antibodies that do not have in vitro neutralization activity but confer in vivo protection, have also been reported for influenza virus (27), herpesvirus (28), cytomegalovirus (29), alphavirus (30), and dengue virus (31). Therefore, although CR3022 does not neutralize SARS-CoV-2 in vitro, it is possible that this epitope can confer in vivo protection.

So the lack of in vitro neutralisation isn't a showstopper.

Still, that bit reads like reaching to me. We shouldn't expect this antibody to be that useful, although we can hope.

Moreover, i suspect we shouldn't think about manufactured antibodies as a treatment for COVID-19 at all, as i doubt we have the manufacturing capacity for biologicals to use them against a pandemic on this scale.

Rather, i think this points towards this part of the virus being a good target for vaccines. If you can make a nice little edited version of that epitope (the SARS-nCov-2 version), you might be able to use it to make a vaccine which raise neutralising antibodies.

[0] https://science.sciencemag.org/content/early/2020/04/02/scie...

It's the light chain that binds, you can modify heavy chain to do what you need and said.

This is what's done when humanizing antibodies too.

The extra infection potential is when the virus or bacteria can survive or thrive inside macrophages or monocytes, which react to opsonized particles, such as with antibodies.

You can make IgA or IgM instead to prevent this mechanism. They work by polymerization to bind whatever they attach to. Former is typically not activating the rest of immune system, while IgM would activate everything strongly perhaps inducing your own production.

From my understanding when an antibody attaches to a virus it causes a signal for T-cells to eat the and destroy the virus. So the antibody would be effective in getting the body to destroy any virus found. However I don't think it would create any sort of immune memory which is what a vaccine or recovering from the illness by yourself would do.

That said it would be fantastic in that it could provide some immunity protection for a while why the antibodies are active in your body allowing health care workers to be safer. Might also be very helpful in creating firewalls in institutions like old folks homes or hospitals.

It may simply be the normal predator-prey dynamic. Even if the predator is infinitely more powerful than the prey it's not in their interest to wipe the prey out. They want to leave enough prey for tomorrow. And if there are defector predators that try to gain an edge by eating more than is sustainable, other predators will try to stop them from doing so.

Now, before you object: it's not always perfectly balanced like this. Sometimes the prey does go extinct.

They aren't rampantly social.

Maybe they can't fight it off and die. OTOH, a spider can lay hundreds or even thousands of eggs, so it's enough if a tiny fraction will be able to reproduce.

Short answer. Money. You might like this podcast episode from planet money https://www.npr.org/2020/03/06/812943907/episode-977-wheres-....

It sticks to a virus protein, so you can use that virus protein to find it!

Typically, you first test the blood to see if there are any antibodies in that blood of interest. E.g., collect blood sample, harvest serum from blood by coagulation and centrifugation, apply serum to surface coated with COVID protein(s), wash away unbound material, detect whether antibodies to serum have bound to surface coated with COVID proteins. If yes, then this is a blood sample of interest. You could also test for neutralizing antibodies in parallel/before/after/instead in a viral replication assay. Once you have identified the blood as containing what you want, you then harvest more and collect mature B cells. Mature B cells each produce one antibody. You isolate the B cells by limiting dilution and/or immortalize them by fusion with a special type of cell to make a hybridoma to isolate clonal populations of single cells that are maintainable. Then you test each clonal population for whether it produces the antibody of interest, isolate the nucleic acid that encodes that antibody and put it into a cell type suitable for manufacturing. There are other ways to do it, but the above is fairly standard. It is laborious and easy to mess up and takes time (1 to 2 months) to do correctly. Any step can go wrong and require starting over.