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Face transplant recipient’s donor face now failing

latimes.com

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Re: Face transplant recipient’s donor face now failing

#41

Post by [deleted] »

abbirdboy wrote: post #22
peterlk wrote: post #12

Earlier quoted context omitted.

I just finished up an introductory biology lecture series, and this suddenly makes less sense to me than it did before. What is it about the foreign cells that is identified as foreign by the host cells? The cells ought to be remarkably similar. They're human, with the same function/pluripotency using the same protein interactions. So why attack it?

Adding to some of the other comments: Leukocytes (immune cells) such as B and T cells will undergo "education" when they are developing. For example, B cells, before being released, will go through something called central tolerance in the bone marrow. If the B cell receptors bind a "self" antigen (markers that are associated with our own cells) while developing, it will go through negative selection and be destroyed…

[deleted]

Re: Face transplant recipient’s donor face now failing

#42

Post by refurb »

peterlk wrote: post #12
Medicalidiot wrote: post #7

This is to be expected. Any time we do any transplant immunosupressants are given to the recipient for the rest of their life, but this only slows the inevitable. Heart transplants recipients all get accelerated atherosclerosis. Lung transplant recipients all get long term fibrosis. We buy time with these procedures and do everything we can to keep them going, but if you have a transplant, you're in a really bad spot…

I just finished up an introductory biology lecture series, and this suddenly makes less sense to me than it did before. What is it about the foreign cells that is identified as foreign by the host cells? The cells ought to be remarkably similar. They're human, with the same function/pluripotency using the same protein interactions. So why attack it?

Proteins on the surface of cells identify them as “self” or “not self”. MHC (major histocompatability complex) plays a large role.

Re: Face transplant recipient’s donor face now failing

#43

Post by Avamander »

ravar wrote: post #30
Medicalidiot wrote: post #7

This is to be expected. Any time we do any transplant immunosupressants are given to the recipient for the rest of their life, but this only slows the inevitable. Heart transplants recipients all get accelerated atherosclerosis. Lung transplant recipients all get long term fibrosis. We buy time with these procedures and do everything we can to keep them going, but if you have a transplant, you're in a really bad spot…

I recently listened to this podcast. https://news.ycombinator.com/item?id=21051174 It is about widespread fraud in the drug industry. During the interview it was mentioned that some people are seeing organ failure due getting fraudulent drugs from abroad. It is possible that this is not what happened in this case, but it seems plausible. To anyone who has the time, listen to this podcast. It was really educational an…

Interestingly the EU is working on building a verification service for pharmaceuticals but some countries are pushing back.

Re: Face transplant recipient’s donor face now failing

#44

Post by hinkley »

arbitrage wrote: post #3

“There are so many unknowns and so many new things we are discovering,” said Dr. Bohdan Pomahac, director of plastic surgery transplantation at Brigham and Women’s and one of Tarleton’s surgeons. Still, he said, “It’s really not realistic to hope faces are going to last (the patient’s) lifetime.”

What's the mortality rate on transplants? If you keep doing the same surgery over and over, won't the patient eventually die on the operating table?

Re: Face transplant recipient’s donor face now failing

#45

Post by Footkerchief »

airstrike wrote: post #33
abbirdboy wrote: post #22

Earlier quoted context omitted.

Adding to some of the other comments: Leukocytes (immune cells) such as B and T cells will undergo "education" when they are developing. For example, B cells, before being released, will go through something called central tolerance in the bone marrow. If the B cell receptors bind a "self" antigen (markers that are associated with our own cells) while developing, it will go through negative selection and be destroyed…

Thanks for this. I'm perpetually amazed at how mind-bogglingly complex the human body is. > while developing, it will go through negative selection and be destroyed Can you share more about how this process works? Even just a link would do. Thank you!

https://en.wikipedia.org/wiki/V(D)J_recombination

Re: Face transplant recipient’s donor face now failing

#46

Post by zaroth »

ravar wrote: post #30
Medicalidiot wrote: post #7

This is to be expected. Any time we do any transplant immunosupressants are given to the recipient for the rest of their life, but this only slows the inevitable. Heart transplants recipients all get accelerated atherosclerosis. Lung transplant recipients all get long term fibrosis. We buy time with these procedures and do everything we can to keep them going, but if you have a transplant, you're in a really bad spot…

I recently listened to this podcast. https://news.ycombinator.com/item?id=21051174 It is about widespread fraud in the drug industry. During the interview it was mentioned that some people are seeing organ failure due getting fraudulent drugs from abroad. It is possible that this is not what happened in this case, but it seems plausible. To anyone who has the time, listen to this podcast. It was really educational an…

The human brain is wired to make connections, but it's important to step back and realize the universe of "plausible" explanations are almost infinite.

It is nothing more than rank speculation that these two stories are somehow related. The world is teeming with junk science like this, and it can be dangerous and even fatal. (E.g. anti-vexers). That's why I think it's important to recognize it when you see it, and call it out. Even more-so if you find yourself possibly espousing damaging speculation without a scintilla of evidence.

Re: Face transplant recipient’s donor face now failing

#47

Post by pkaye »

Pete_D wrote: post #32
Medicalidiot wrote: post #7

This is to be expected. Any time we do any transplant immunosupressants are given to the recipient for the rest of their life, but this only slows the inevitable. Heart transplants recipients all get accelerated atherosclerosis. Lung transplant recipients all get long term fibrosis. We buy time with these procedures and do everything we can to keep them going, but if you have a transplant, you're in a really bad spot…

How much of this is mitigated by donor/recipient compatibility (haplotypes? is that the right word?)? Is there no such thing as a purely compatible donor?

Yes identical twins are fully compatible. The first kidney transplant was done between identical twins and the the recipient lived with no anti-rejection medications for decades from what I recall.

Re: Face transplant recipient’s donor face now failing

#48

Post by puranjay »

markkat wrote: post #24
FreeFull wrote: post #9

Earlier quoted context omitted.

I wonder how long it will take until growing organs from the recipient's own stem cells is actually viable. There definitely is some interesting research, and it would completely circumvent the problems with the immune system.

This issue is why I started Forever Labs (YCS17). We bank your stem cells. Immunity presents many difficult problems to be solved. I’d rather worry about the therapeutic developments alone rather than add immunity on top of it.

I'm a little curious how something like this works within the economic framework of a startup. How do you reconcile the inherently long-term nature of your business (I might need my stem cells in a decade or two) with the inherent instability of a startup (you might go out of business within 3 years)?

Re: Face transplant recipient’s donor face now failing

#49

Post by friedegg »

asveikau wrote: post #19
Enginerrrd wrote: post #15

Earlier quoted context omitted.

Because it's part of the arms race with pathogens that has been going on for a billion years since multi-cellular life first appeared. Pathogens do lots of very clever things to hide from the immune system, so the immune system is tuned to detect very subtle changes. The body largely operates on zero-trust network models, except for a few locations where the benefit of a too-active immune system has serious consequen…

I guess auto-immune disease is an example of where it also goes the wrong way for somebody. Probably most of us know somebody with IBD, lupus, or any of the others. It's very common for the body to reject something benign, or ourselves.

Type 1 diabetes is a good example of this, where the body detects its own insulin producing cells as threats and eliminates them. Lots of the research in type 1 treatments isn't just about producing insulin, but figuring out how to prevent the body from destroying it again without all of the risks of immunosupressant drugs.
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