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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

#71

Post by mkl »

alan-crowe wrote: post #51
wongarsu wrote: post #29

Earlier quoted context omitted.

To add to this: if the immune system would just check that the cell is human then every invader would just evolve to pass that check. The only viable way to defend is to mark the cells as belonging to this specific human. That way even if some bacteria evolves to trick my immune system it's unlikely to also trick yours, and the infection can't spread.

Additionally, if the immune system would just check that the cell is human, then humans would be vulnerable to contagious cancer, such as the facial tumor disease suffered by Tasmanian Devils https://en.wikipedia.org/wiki/Devil_facial_tumour_disease

Humans almost certainly are vulnerable to contagious cancer (there are a few known in other species: https://en.wikipedia.org/wiki/Clonally_transmissible_cancer) . We just haven't acquired/discovered any yet.

Re: Face transplant recipient’s donor face now failing

#72

Post by DoreenMichele »

Tarleton, who now lives in Manchester, N.H., told the Boston Globe she has no regrets about the transplant because it dramatically improved her life. She has learned to play the piano and banjo, wrote a memoir and has spoken to many groups about her life. She lost 20 pounds and began walking five miles a week.

“I had such a low quality of life prior to my face transplant. Do I wish it had lasted 10 or 20 years? Of course,” she said.

I was on an email list and a woman who had two lung transplants described some of what she had been through and also asserted she would do it again and had no regrets.

You have to understand these are people who have no other viable options. However bad this is, the alternative is worse.

I wrestle with these questions because I wish we were looking for better answers. I am in no way interested in telling people who have had transplants that they were wrong to choose that for themselves.

But transplants are dramatic, heroic, headline grabbing procedures. Helping people keep their organs functioning so they don't need a transplant has much less capacity to grab headlines and fascinate the public and so on.

We increasingly put our time and effort into really dramatic medical procedures that are very expensive and have a golly, gee whiz factor. I think we are likely largely overlooking better paths that would give a higher quality of life in many cases because they have less razzle dazzle.

Re: Face transplant recipient’s donor face now failing

#73

Post by DoreenMichele »

0x38B wrote: post #57
newnewpdro wrote: post #53

Earlier quoted context omitted.

It appears he's already dead. https://www.ibtimes.com/who-carmen-tarleton-lye-attack-victi...

Quoting the linked article: “I have fully forgiven him and I don’t have the same attitude that a lot of people have with his treatment of me,” Tarleton said. “I have moved on so well and in so many ways. I feel like, for me, it ends a big chapter in my life.” More than what happened to her, what stands out to me is that she's moved on. That's strength. There are things that no one can take away.

You move on so it doesn't steal anymore of your future. It's the only thing you can do. Stewing about it just lets it take yet more of your life when the cost has already been too high.

In most cases, no, the people trying to bleed you emotionally with their pity party for you aren't going to do a damn thing to help improve your quality of life. They will only add to your suffering.

Shutting them down as efficiently as possible as just part of protecting yourself from yet more damage in a cold, cruel world full of assholes.

Re: Face transplant recipient’s donor face now failing

#74

Post by echelon »

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?

> I just finished up an introductory biology lecture series, and this suddenly makes less sense to me than it did before.

The immune system is one of the most complicated and wonderful pieces of biology. It's also scary in the ways that it can malfunction and the challenges it presents to modern medicine.

> What is it about the foreign cells that is identified as foreign by the host cells?

The MHC system is a major determinant of histocompatibility.

https://en.wikipedia.org/wiki/Major_histocompatibility_compl...

https://en.wikipedia.org/wiki/Human_leukocyte_antigen

https://en.wikipedia.org/wiki/Histocompatibility

MHC is an adaptive immune function used to detect foreign antigen that was evolved as a means to combat intracellular pathogens. This cell-surface machinery collects and presents foreign antigens from inside the cell at the cell surface for discovery by immune cells that come into contact. If something "foreign" is found on the MHC, the immune system targets the cell for deletion and upregulates the immune system for further attack.

The genes that code the MHC proteins vary widely between individuals. This can be beneficial as viruses struggle to evolve in a way that evades all MHCs in a population.

Unfortunately, the MHC proteins are themselves a highly reactive antigen that triggers the immune system. Luckily, the body learns during a process called "negative selection" to cull any immune cell receptors that recognize your own MHCs:

https://en.wikipedia.org/wiki/Thymus (search "negative selection").

If any of your own T-cells match your own MHC, they're killed. Unfortunately, your body doesn't know the shape of MHC proteins from donor tissue and can't learn to kill any TCRs that match. And these proteins are incredibly, incredibly polymorphic:

https://en.wikipedia.org/wiki/Human_leukocyte_antigen

Search "variability", then multiply the numbers -- you're not going to find an exact match for you anywhere, unless you have an identical twin. This is why donor databases exist. If you can find a match for one of the variants, it reduces the product of these multiples.

It's very hard to find a tissue match.

When you transplant foreign tissue, it's an antigen.

Fun fact: did you know your immune system genes aren't at rest and are actually evolving right now? Your immune cells run stochastic hill climbing. It's wild. Check out somatic recombination:

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

The immune system is incredibly complicated.

Re: Face transplant recipient’s donor face now failing

#75

Post by magicalhippo »

aphextim wrote: post #35
xwdv wrote: post #25

Earlier quoted context omitted.

I’d say it’s probably more like some kind of checksum against the DNA. If the body detects something has been changed from what was there before it dispatches the white blood cells to kill it off. Immunosuppressants are a way to bypass the checksum, but only for some limited time. Maybe we need a way to change the checksum values altogether, but then the whole body could be rendered rejected and cease to function (de…

I love tech analogies to biological functions. It amazes me how much 'tech' is always running on a cellular/molecular level. Thank you!

Indeed. I had read about it before but viewing these visualizations blew my mind:

https://www.youtube.com/watch?v=SMtWvDbfHLo (DNA transcription)

https://www.youtube.com/watch?v=TfYf_rPWUdY (mRNA translation)

https://www.youtube.com/watch?v=I9ArIJWYZHI (DNA replication)

Re: Face transplant recipient’s donor face now failing

#76

Post by thealexbaron »

randyrand wrote: post #69
kls wrote: post #52

Earlier quoted context omitted.

Yeah not good, how can men bring themselves to such violence against women. I am sitting here as I write this looking at my wife and cant for the life of me fathom doing such a ghastly act to her or even a woman that I don't know, no matter what I believed (real or imaginary) their transgressions where against me. I don't know the back story but if he was capable of doing this, she probably left him for good reason a…

> I am sitting here as I write this looking at my wife and cant for the life of me fathom doing such a ghastly act to her or even a woman that I don't know. Not trying to 1-up you but I can't imagine how anyone could do this to anyone. Edit: to those curious what happened to the husband. 30 to 70-year sentence (age 52 at the time), died in prison. https://www.vnews.com/Man-Convicted-of-Maiming-Vermont-Woman...

It's so sad what she had to experience

Re: Face transplant recipient’s donor face now failing

#77

Post by paggle »

robohoe wrote: post #65
eecc wrote: post #59

The f*cking prick needs to be sat in front of a picture of his victim and stare at it 14 hrs a day. Then be given 2 hrs to wash and feel what he has brutally taken away from his victim. Then sleep 8 hrs in order to be fully aware for the next sitting the next day. For about... the rest of his useless life.

He’s supposedly dead [0]. https://www.vnews.com/Man-Convicted-of-Maiming-Vermont-Woman...

Cases like this are why torture should be a legal sentence for the worst crimes where guilt is not in doubt.

Re: Face transplant recipient’s donor face now failing

#78

Post by paggle »

chrshawkes wrote: post #55

This is a horrific story I wish I didn't read about. The husband only got a 30 to 70 year sentence for this??? He died in prison but this is a case for the death penalty all the way. This guy ended up dying of natural causes in prison. This woman is living a tortured existence and this guy gets 3 hots and a cot & cable TV until he dies. Disgusting.

The US “progressives” think much more about the poor murderers and their horrible lives in prison instead of the people they murdered.

Re: Face transplant recipient’s donor face now failing

#80

Post by onemoresoop »

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?

My understanding is that most cells in the human body regenerate. What I don't understand is how cells that are part of the transplant regenerate. Do they use the host or the transplanted DNA to regenerate?
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