Using Helium to Freeze Transplantable Organs Closer to Reality

Every year, approximately 28,000 people in the United States receive organ transplants. Out of these, over half are kidney transplants and one-fourth are liver transplants. While organ transplants can save lives, ensuring a constant supply of organs can be a significant challenge. However, most organs are only viable for a short time when removed from the body.

In most cases, physicians have only a few hours to find a suitable recipient for a donated organ. For kidneys, physicians have a little more than 24 hours before it degrades beyond viability. However, this may change in the future.

"[Organ degradation] precludes any chance of banking organs and makes every transplant an emergency procedure, often in the dead of night... when patients aren't ready," notes Stephen van Sickle, a researcher at Arigos Biomedical who helped develop the new organ transplant process.

In total, approximately one-fifth of all donated kidneys are thrown away every year due to a lack of suitable donors or clinics. However, freezing these organs may increase viability times and improve patient access to transplant organs.

Freezing donated organs comes with a series of significant challenges. Since ice crystals form when an organ is frozen, shards of ice can cause significant cellular and tissue damage. Vitrification, a process through which a low-toxicity antifreeze is injected into a tissue, can help reduce the risk of ice crystals in frozen, donated organs. However, vitrification is difficult with complex organs like kidneys and hearts. Since high quantities of antifreeze are toxic and frozen organs are prone to crack, vitrification doesn't always guarantee success.

With persufflation, helium is used to replace blood in a donated organ. This allows the organ to cool at a rapid rate, requiring less antifreeze. Since pockets of tissue are separated by helium, the risk of shattering is greatly reduced. If the new technique proves a success, on-demand donor organs may be available for recipients in the future.