Towana Looney donated a kidney to her mother in 1999, but the other kidney failed years later due to pregnancy complications. Now, a 53-year-old Alabama man has become the latest recipient of a gene-edited pig kidney — and is currently the only living person in the world to have received an animal organ transplant, NYU Langone Hospital in New York City announced Tuesday.
“I’m very happy, I’m happy that I got this gift, this second chance at life,” Looney said during a press conference three weeks after the procedure.
Xenotransplantation, the transplantation of organs from one species to another, has long been an exciting but elusive scientific goal. Early experiments in primates failed, but recent advances in gene editing and immune system manipulation have brought the dream closer to reality.
Pigs have become ideal donors: they grow quickly, produce large litters, and are already part of the human food supply.
Advocates hope the approach could help solve a severe organ shortage in the United States, where more than 100,000 people are waiting for a transplant, including more than 90,000 in need of a kidney.
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Last chance
Looney has lived with dialysis since December 2016 – eight grueling years. High blood pressure caused by preeclampsia took its toll, leaving her with chronic kidney disease.
Despite being prioritized on the transplant waiting lists as a living donor, her search for a compatible kidney hit a frustrating dead end. Her unusually high levels of harmful antibodies made rejection almost inevitable, and when her body lost the viable blood vessels to support dialysis, her health deteriorated.
Among other options, Looney applied for a pig kidney transplant clinical trial and finally underwent the seven-hour operation on November 25.
When asked how she felt afterward, Looney’s joy was contagious. “I’m full of energy, I have an appetite… and of course I can go to the bathroom. I haven’t walked in eight years!’ she laughed, adding that she plans to celebrate at Disney World.
Jamie Locke, a surgeon on the transplant team, described the results in awe. “The kidney functioned essentially the same as a kidney from a living donor,” she said, adding that Looney’s husband saw the rosy color in her cheeks for the first time in years.
“This is the miracle of transplantation.”
Cautious optimism
Looney’s operation is the third time a gene-edited pig kidney has been transplanted into a person who did not die.
Rick Sleiman, the first recipient, died in May, two months after surgery at Massachusetts General Hospital. The other, Lisa Pisano, initially showed signs of recovery after surgery at NYU Langone, but the organ had to be removed after 47 days and she died in July.
Looney, however, was not terminally ill before the transplant, noted Robert Montgomery, who oversaw the operation. Each case, he emphasized, provides important lessons for improving methods.
The kidney was provided by biotech company Revivicor, which breeds genetically modified cattle in Virginia. Massachusetts-based eGenesis supplied the kidney for Sleiman.
Looney’s organ has 10 genetic edits to improve compatibility with the human body, an advance over Revivicor’s previous efforts, which used single-gene-edited kidneys and included a pig’s thymus gland to help train the host’s immune system and prevent rejection.
Montgomery, a pioneer in the field who in 2021 performed the world’s first transplant of a gene-edited pig organ into a brain-dead patient, said both techniques are likely to enter clinical trials “probably this time next year or even earlier.”
“This is a watershed moment for the future of transplantation,” said Kevin Longino, CEO of the National Kidney Foundation. A nonprofit survey shows patients and families favor faster clinical trials, believing the risk of inaction outweighs the uncertainty of xenotransplantation.
Looney was discharged on December 6 to a nearby apartment in New York. Although her high antibody levels are still a concern, doctors are closely monitoring her using wearable devices and trying a new medication regimen to prevent rejection.
Periodic hospital visits may still be required, but the team remains optimistic that she can return home in three months.
