Buying time: the push to keep donor organs alive for days, not hours

Donor organs last only hours on ice. Researchers are testing supercooling and perfusion to stretch that window and shrink transplant waitlists.

Donor organs stay viable only a few hours outside the body, even chilled on ice, and that narrow window is part of why so many transplants never happen. Researchers want to build organ banks that could hold tissue for days, weeks, or longer, and several groups are chasing different routes there.

One team supercooled pig kidneys, held them at -4C for days, and reimplanted them into pigs; those kidneys reportedly performed better than ice-stored ones, and the approach avoided cryoprotectant chemicals. Pig organs are roughly human-sized, which makes the result meaningful, though it remains animal work rather than human transplantation. Other efforts include machine perfusion devices that pump nutrients to keep livers and kidneys going for around 24 hours, and a Valencia system nicknamed 'Mother' that kept a human uterus alive for a day. Full cryopreservation, routine for eggs and sperm at -196C, has never worked for a whole human organ.

If preservation stretches to days or weeks, organs could be matched, shipped, and scheduled instead of raced against the clock, widening the effective donor pool and cutting waitlist deaths. That turns a scarce, time-locked resource into something closer to inventory.

What to watch is whether supercooling and perfusion move from animal models to human trials, and whether cryopreserved organs can ever be thawed intact. Reports that rewarmed brain cells 'bounced back' do not mean those cells were alive or that reanimation is possible. This is early, ongoing research, summarized from a newsletter.

Source: MIT Tech Review