Update on freezing and thawing organs (nanowarming)
#8 A better way to store organs on the horizon?
In the past, freezing organs, or any biological tissue, could cause ice crystals to form and rupture membranes. This was a big issue, because after freezing you would have lots of little breaks at the cellular level. This freezing issue was resolved by snap freezing to avoid ice crystal formation. However there were still big issues in thawing large masses of biological material, like an organ or an entire organism.
In June 2023 a new technique was tested on mouse kidneys to freeze and then thaw and transplant, with full kidney function being restored. They are calling this technique “nanowarming”.
This is huge. If this can be done in other organs, this could potentially solve the organ shortage, because freezing an organ should make it viable until needed. You can read details from the links below, but briefly the technique is to introduce small iron particles into the organ, flash freeze to avoid ice crystals, then warm using magnetic fields. This technique “employs alternating magnetic fields to heat nanoparticles within the organ vasculature, to achieve both rapid and uniform warming”.
The current technique is crude by comparison where the deceased donor has to be kept on life support until the organs can be removed, and that is emotional for the relatives, expensive for the hospital, and gives a very short medical window for the recipient. And this only works when an organ donor dies and happens to match someone who needs an organ at that point in time. In other words, the current methods are awful, and in dire need for improvement. This could be that improvement.
Imagine a new system, where when you die, you can have your organs frozen forever, or until needed by someone, and the doctors can take their time to prepare, when someone is found who needs them. Or imagine a subsequent improvement, where you could have tissue removed and grown into new organs, then frozen until needed. If you have an automobile accident, they could potentially have an organ in the bank for you, possibly even one from you, which would solve the histocompatibility issues nicely. If the organ was from you, it would not be rejected by your immune system. And even if you did not have some of your organs on file, if this bank was large enough, they would have a much larger selection, and therefore more likely to have a compatible, but not perfectly compatible, organ available.
And now I am goind to explore a longer term potential, which some might call science fiction. But imagine if this technique was extended to be applicable to whole organisms. It brings us very close to being able to freeze entire animals and bring them back. I’ll admit that last sentence was a leap, but it would potentially solve some extinction issues. It also brings us closer to being able to freeze people until a cure for their disease is found - a holy grail of science fiction for some time now.
Here is the article which inspired this rant:
And this is the original research:
Zonghu Han et al, Vitrification and nanowarming enable long-term organ cryopreservation and life-sustaining kidney transplantation in a rat model, Nature Communications (2023). DOI: 10.1038/s41467-023-38824-8