Researchers at the University of Minnesota have for the first time developed a reliable protocol for long-term storage, heating, and successful transplantation of a functionally preserved organ in an animal. Their new “nanoheating process” allows the organ to be heated quickly and evenly from the inside, not just on its surface. This opens the door to long term organ preservation and increased availability of human organs for life-saving transplants.
Organs can be preserved using long-term cryopreservation techniques, such as vitrification, the process of pumping the organ with cryoprotective chemicals and cooling it quickly enough so that ice crystals do not form. The problem arises, however, when attempting to return the organ to its body temperature.
To solve this problem, scientists have developed a new “nanoheating process” that quickly and evenly heats the organ from the inside, not just on its surface. The new method uses iron oxide nanoparticles that fill the organ’s blood vessels. When the nanoparticles are activated by electromagnetic waves, they heat the organ evenly, similar to the way water in food is heated in a microwave oven.
In their experiments, the team cryogenically stored rat kidneys for up to 100 days, then successfully heated them, cleaned them of the cryoprotective chemicals, and transplanted them back into five living rats. At 30 days, all of the rats had full kidney function, indistinguishable from a normal organ.
The big question is whether this technology can be applied to humans. It is estimated that 20 percent of kidneys donated for transplantation each year are wasted because they expire before the recipient can access them. With this cryopreservation technology applied to humans, this problem could potentially become a problem of the past.
The researchers hope to ramp up their efforts by demonstrating the process using pig kidneys. Although they estimate it could be “several years” before the method is applied to humans, the team says they are “confident” they will be able to accomplish this with some further research.