5 ms·

The pig was modified to remove presentation of immunogenic sugars on the cell surface. Unfortunately, the recipient needs to be on immunosuppressants the rest o

The pig was modified to remove presentation of immunogenic sugars on the cell surface. Unfortunately, the recipient needs to be on immunosuppressants the rest of their life. This rekindles discussions back in school about chimeras... in order for the organs to be immunocompatible, the donor needs to be partially human. What % is too human to harvest for organs? I suppose it's still too soon to answer such questions, but apparently, 0% acceptable.

badRNG 5y ago
I don't think it is all that uncommon for regular human-to-human transplant recipients to be on immunosuppressants for life. If I'm not mistaken, that's the case for all organ recipients, but there may be exceptions. I think the concept of "immunocompatibility" can refer to a spectrum of outcomes that we haven't gotten down even for transplants within our own species.
- giarc 5y ago
  Yes all transplant patients receive immunosuppressants. The only transplant that wouldn't would be an allogenic stem cell transplants (uses the persons own stem cells), however these people typically don't have an immune system to begin with.
dnautics 5y ago
> What % is too human to harvest for organs I don't think it's really measurable, because a meaningful "%" implies a relatively context-free, relatively uniformly distributed importance to genetic sequence. The most immunogenic sugar is glycolylneuraminic acid. Humans are incapable of making this sugar so it's immediately recognizable as alien by the human immune system. You could in theory disable production of this sugar with a single base pair mutation which (if that's how you did it) would make this .000001% sequence difference extremely important over almost any other sequence point. As a side note it's a matter of speculation that the lack of this sugar is an evasion mechanism for species-jumping flu. Edit: tick thing was wrong, I had misremembered! Thank you smart reader who has since deleted their comment calling me out.
- deleted 5y ago
  [deleted]
robbiep 5y ago
They’re not making the pig more human, they’re removing the markers of ‘foreign’ that would make it an immune target. So it’s a nice vanilla organ that minimally attracts the attention of the immune system.
- dnautics 5y ago
  On the other hand (and I am being flippant... Slightly) how do you know that removing this one gene doesn't unlock consciousness?
  - TulliusCicero 5y ago
    I mean pigs are already "conscious" on some level, I'm sure.
    - deleted 5y ago
      [deleted]
  - serf 5y ago
    >how do you know that removing this one gene doesn't unlock consciousness? i'm not the poster you're replying to, but for me the answer is this : consciousness appears to me to be a constellation of traits rather than a trait itself that would be easily acquired with a genetic shift. One could then say : 'What if the one we flip is the thing that finishes the constellation of traits that activates consciousness?' , and sadly I must confess that I believe that if that were to happen to an entity without sufficient communications methods that it would probably remain unknown and subject to whatever experiences whatever sensory organs it may have provides it, while we remain entirely unaware for some time. Also, a point that I agree upon by the poster who replied to you with me ; we don't seem to hold conscious entities in very high regard -- only human ones.
    - VRay 5y ago
      relevant SMBC: https://www.smbc-comics.com/comic/intelligence-2 https://www.smbc-comics.com/comic/intelligence-2
majormajor 5y ago
What part do you think opens that door? Human organ recipients also need immunosuppressants forever, outside of rare cases. This particular case sounds like a very small modification to the source pig, not a pig carrying a human organ.
- XorNot 5y ago
  I mean I imagine there's research trying to do exactly that: you can identify beating heart cells very early on in embryos, and chimeric organisms are a thing. I imagine someone somewhere is trying to swap out those early cells with human heart cells to see if you can literally grow a pig with a human heart.
cwkoss 5y ago
I think the nervous system is really the only part that I'd have ethical concerns about. If they can grow a pig with a 99% human heart, I don't see why that should be more ethically concerning that harvesting a 100% pig heart.
- LeifCarrotson 5y ago
  The concern, I think, that it's obviously unethical to grow a 100% human child and then harvest its heart, right? You're talking about a living, feeling, thinking person! Causing them to suffer or to die is morally wrong, conversely, their life and their right to life have precious, incalculable, sacred value. The thought of harvesting, murdering a human being for one of their organs is repulsive, harvesting them for food is cannibalism and a taboo of the highest order. And yet many humans eat bacon for breakfast without a second thought. On the operating table, the human heart and pig heart would probably be indistinguishable to a layperson, so why is the one sacred and the other free for the taking?
  - tired_medicine 5y ago
    This is an ethical concern which is so completely removed from reality that it borders on satire. This is why no one takes bioethicists seriously anymore.
- steve76 5y ago
redanddead 5y ago
I think people will only accept 3d printed organs, pig and animal things are too controversial for some people. I was listening to a podcast on the CBC about AI and consciousness, and the idea that humans are distinct from an animal (beastmachine, great name for a butcher shop btw) comes from Descartes, who we revere in philosophy (for fair reasons).. I think we can't blame people for wanting to separate themselves from animals.
rakejake 5y ago
Speaking of chimeras, there is a Greg Egan short story from his book "Axiomatic" about a human leopard chimera which is bred by an eccentric billionaire specifically to pose for a painting. The actual story is even crazier.

badRNG 5y ago

I don't think it is all that uncommon for regular human-to-human transplant recipients to be on immunosuppressants for life. If I'm not mistaken, that's the case for all organ recipients, but there may be exceptions. I think the concept of "immunocompatibility" can refer to a spectrum of outcomes that we haven't gotten down even for transplants within our own species.

giarc 5y ago
Yes all transplant patients receive immunosuppressants. The only transplant that wouldn't would be an allogenic stem cell transplants (uses the persons own stem cells), however these people typically don't have an immune system to begin with.

dnautics 5y ago

> What % is too human to harvest for organs I don't think it's really measurable, because a meaningful "%" implies a relatively context-free, relatively uniformly distributed importance to genetic sequence. The most immunogenic sugar is glycolylneuraminic acid. Humans are incapable of making this sugar so it's immediately recognizable as alien by the human immune system. You could in theory disable production of this sugar with a single base pair mutation which (if that's how you did it) would make this .000001% sequence difference extremely important over almost any other sequence point. As a side note it's a matter of speculation that the lack of this sugar is an evasion mechanism for species-jumping flu. Edit: tick thing was wrong, I had misremembered! Thank you smart reader who has since deleted their comment calling me out.

deleted 5y ago
[deleted]

robbiep 5y ago

They’re not making the pig more human, they’re removing the markers of ‘foreign’ that would make it an immune target. So it’s a nice vanilla organ that minimally attracts the attention of the immune system.

dnautics 5y ago
On the other hand (and I am being flippant... Slightly) how do you know that removing this one gene doesn't unlock consciousness?
- TulliusCicero 5y ago
  I mean pigs are already "conscious" on some level, I'm sure.
  - deleted 5y ago
    [deleted]
- serf 5y ago
  >how do you know that removing this one gene doesn't unlock consciousness? i'm not the poster you're replying to, but for me the answer is this : consciousness appears to me to be a constellation of traits rather than a trait itself that would be easily acquired with a genetic shift. One could then say : 'What if the one we flip is the thing that finishes the constellation of traits that activates consciousness?' , and sadly I must confess that I believe that if that were to happen to an entity without sufficient communications methods that it would probably remain unknown and subject to whatever experiences whatever sensory organs it may have provides it, while we remain entirely unaware for some time. Also, a point that I agree upon by the poster who replied to you with me ; we don't seem to hold conscious entities in very high regard -- only human ones.
  - VRay 5y ago
    relevant SMBC: https://www.smbc-comics.com/comic/intelligence-2 https://www.smbc-comics.com/comic/intelligence-2

majormajor 5y ago

What part do you think opens that door? Human organ recipients also need immunosuppressants forever, outside of rare cases. This particular case sounds like a very small modification to the source pig, not a pig carrying a human organ.

XorNot 5y ago
I mean I imagine there's research trying to do exactly that: you can identify beating heart cells very early on in embryos, and chimeric organisms are a thing. I imagine someone somewhere is trying to swap out those early cells with human heart cells to see if you can literally grow a pig with a human heart.

cwkoss 5y ago

I think the nervous system is really the only part that I'd have ethical concerns about. If they can grow a pig with a 99% human heart, I don't see why that should be more ethically concerning that harvesting a 100% pig heart.

LeifCarrotson 5y ago
The concern, I think, that it's obviously unethical to grow a 100% human child and then harvest its heart, right? You're talking about a living, feeling, thinking person! Causing them to suffer or to die is morally wrong, conversely, their life and their right to life have precious, incalculable, sacred value. The thought of harvesting, murdering a human being for one of their organs is repulsive, harvesting them for food is cannibalism and a taboo of the highest order. And yet many humans eat bacon for breakfast without a second thought. On the operating table, the human heart and pig heart would probably be indistinguishable to a layperson, so why is the one sacred and the other free for the taking?
- tired_medicine 5y ago
  This is an ethical concern which is so completely removed from reality that it borders on satire. This is why no one takes bioethicists seriously anymore.
steve76 5y ago

redanddead 5y ago

I think people will only accept 3d printed organs, pig and animal things are too controversial for some people. I was listening to a podcast on the CBC about AI and consciousness, and the idea that humans are distinct from an animal (beastmachine, great name for a butcher shop btw) comes from Descartes, who we revere in philosophy (for fair reasons).. I think we can't blame people for wanting to separate themselves from animals.

rakejake 5y ago

Speaking of chimeras, there is a Greg Egan short story from his book "Axiomatic" about a human leopard chimera which is bred by an eccentric billionaire specifically to pose for a painting. The actual story is even crazier.