Texas A&M’s Matthew Powell Palm supercools pig kidneys to -4°C for 72 hours

Time is the hidden bottleneck in kidney transplantation. Once an organ is removed, it starts to deteriorate, and surgical teams usually have only hours to get it into a recipient. In most current practice, organs are kept on ice at around 4°C (39°F), and ice works for a reason: colder slows metabolism and buys time. The catch is brutal. Ice can still cause damage, and it only reliably extends storage to a limited window.

Matthew Powell Palm, a thermodynamicist at Texas A&M University, is trying to change that math with a method that avoids ice formation altogether. In new research using pig organs, his team used a device to cool kidneys to -4°C (25°F) without forming any ice, and showed that after supercooling for 72 hours the kidneys recover once transplanted into pigs. The kidneys do not just “survive” on paper. Once the 24-hour supercooled kidneys were transplanted, they immediately began producing urine, a key indication that the organs were working. The team also measured kidney function markers and found the organs appeared to work normally within about 10 days of transplantation. Even better for anyone stuck in real-world logistics, they report that kidneys supercooled for 48 and 72 hours performed similarly, with recovery patterns that beat the typical pace seen in other studies.

Why does this matter so much outside the lab? Because the wait list is not abstract. In the US alone, there are more than 104,000 people waiting for a kidney transplant. It is estimated that 17 people die every day in the US while waiting for a transplant. And the supply problem is layered. Even when kidneys are donated, a significant share never makes it to a recipient in usable condition. In some years, around one in three donated kidneys are discarded, often because they end up too degraded by the time they reach a potential recipient.

Part of that degradation timing is shaped by current storage assumptions. Kidneys can be stored on ice for around 24 hours, or placed in devices that aim to mimic body conditions for up to around 24 hours. Myer’s point in the source is plain and practical: that’s often not enough time to evaluate a kidney, match it to a suitable recipient, and physically transport the organ. Kevin Myer, president and CEO of LifeGift, an organ procurement organization based in Texas and not involved in the research, describes the “assumed limit” for kidney transplantation as 18 to 24 hours. If doctors could get up to 72 hours, Myer says, “that would change everything.” That is not marketing. It is a logistics reframe: more time for evaluation and matching, more flexibility in transport, and potentially enabling international donations and cheaper transport options.

The technical leap in Powell Palm’s approach is less about “magic freezing” and more about thermodynamics. Teams worldwide have explored storing organs for longer by cooling them further and sometimes adding cryoprotectants, which act like antifreeze but can have side effects and would need approval for human use. Powell Palm, described in the source as a thermodynamicist, explored an approach aimed at preventing ice formation at temperatures a little below 0°C without needing cryoprotectants. The device is essentially a hermetically sealed chamber with a transparent lid. A base component monitors the organ’s temperature and checks for the formation of ice. Organs are submerged in a solution already commonly used to preserve them for transplant.

To test this, Powell Palm and colleagues created a pig model built around a fair comparison. First they removed single kidneys from pigs and flushed them with the commonly used solution to remove blood, mirroring transplant prep. Some kidneys stayed on ice for either two hours or 24 hours to reflect standard conditions in human transplantation. Others were placed in the supercooling device for 24, 48, or 72 hours. Then each stored kidney was transplanted back into the original donor pigs, using the animal’s second kidney as the one removed and replaced. Once transplanted, the 24-hour supercooled kidneys began producing urine immediately. The source also notes that a kidney supercooled for 72 hours recovers once transplanted back into a pig, and that the recovery is slower than kidneys stored on ice for two hours but much faster than kidneys kept on ice for 24 hours.

Beyond initial function, the team also reports longer-term outcomes in the animals. Over a 30-day period, pigs grew by around 30%, and their kidneys grew with them. The kidneys nearly doubled in size to compensate for both the pigs’ growth and the lack of a second kidney. In addition, the team monitored one pig for 200 days, then removed and analyzed its kidney. Even at that point, Powell Palm says the organ looked healthy. The findings were presented at the American Transplant Congress in Boston last month.

There is also comparative context from other work. Earlier this year, researchers in Canada showed they could cool pig kidneys to below-zero temperatures and transplant them into pigs, but their protocol included a cryoprotectant and organs were stored up to 48 hours. Those organs survived for a week. In contrast, Powell Palm’s team reports supercooling for 72 hours with evidence of favorable performance over 30 days or more. Powell Palm frames it as “the first time this has ever been reported in history” in the source. Extra time could be decisive because it translates directly into how many discarded organs might be saved and how often recipients can get viable matches before degradation makes decisions irreversible.

Regulation and scaling are the next hurdles executives should watch. Powell Palm and colleagues think the absence of cryoprotective chemicals could support an accelerated approval pathway with the US Food and Drug Administration, allowing testing of the device in human transplantations. The device is also described as simple and compact, with portability demonstrated by transporting supercooled kidneys across the US in the back of a Kia Sorento. It has not yet been tested for air travel, but Powell Palm says that from a stability perspective, the approach is an even higher bar. Powell Palm and his colleague Sebastian Giwa plan to launch a company focused on developing the technology and other protocols that “stop biological time” in the coming months. If they are right, the winner will not be just a new storage technique. It will be a new operating window for every system that currently depends on organs staying viable long enough to reach the right person.