Across the U.S., 22 people die waiting for an organ transplant every day. And even when organs are available, many fail to reach a matched recipient before becoming unusable.
Today, about 120,000 people are on the waitlist for an organ transplant in the U.S., suggesting that there’s a significant shortage of organs. But in many cases, organs are available, just at the wrong time. Deep freezing could transform the donation process, yet freezing and thawing can wreak havoc on tissues.
Scientists have more or less solved the freezing process, and they’re making strides in the thawing portion, according to a new study published yesterday in Science Translational Medicine. By creating magnet-powered nanoparticle superheaters for preserved tissue, a research team, led by scientists at the University of Minnesota, is striving for just that. The nanoparticles revitalize the cryopreserved tissues—which are cooled and stored at extremely low temperatures—by evenly warming the surrounding tissue. When the heating is done, they are simply washed away.
Here’s Lauran Neergaard, reporting for the Associated Press:
The nanowarming could heat 10 to 100 times faster than previously attempted methods, [lead author John] Bischof said. After nanowarming, small samples of human skin cells and pig arteries were as healthy-looking as those thawed by today’s standard heating. Larger samples of pig heart tissue too big for today’s heating tools also were thawed by the new technology without signs of damage, the researchers reported.
The life-span for organs outside the body is short—a heart or lung, for example, is only viable for four to six hours. New preservation technology would potentially allow donated organs to be shipped and stored even before a recipient is found.
The procedure, which the researchers call “nanowarming,” bathes pieces of tissue in nanoparticles that begin rapidly warming when triggered by a magnetic field. Existing warming methods are only able to heat tissue samples of a few milliliters in volume. But nanowarming can thaw up to 50 milliliters without leading to damaging cracks or crystals.
There’s still much progress to be made before entire organs are trialed, though. A kidney is about 450-500 milliliters in volume, and in order to preserve full organs, nanoparticles would have to be embedded much deeper into the tissue.
Some experts are skeptical of the technology’s potential, arguing that simply because tissues were successfully warmed up in a lab doesn’t mean they would function properly once transplanted into an animal. However, other specialists say the new research is proof that organ banks may be something of the near future.
The team is currently testing the procedure on rabbit kidneys, working to ensure uniform deployment of nanoparticles throughout whole organs.