Chinese researchers have reported new advancements in the pursuit of animal-to-human organ transplants, successfully transplanting a genetically modified pig kidney into a human patient and making progress toward the potential use of pig livers.
A Chinese patient has become the third person worldwide known to be living with a gene-edited pig kidney. The same research team also conducted an experiment transplanting a pig liver into a brain-dead individual, a step that could pave the way for future xenotransplantation efforts.
Scientists are modifying pig genes to make their organs more compatible with humans, aiming to address the critical shortage of transplantable organs. Previous xenotransplants in the U.S.—including two pig heart and two pig kidney transplants—were short-lived.
However, two more recent pig kidney recipients in the U.S. are showing promising outcomes: an Alabama woman who underwent surgery in November and a New Hampshire man who received a transplant in January. A U.S. clinical trial is now on the horizon.
Nearly three weeks after the kidney transplant, the Chinese patient "is very well" and the pig kidney is functioning effectively, Dr. Lin Wang of Xijing Hospital at the Fourth Military Medical University in Xi’an told reporters this week.
Wang, a member of the hospital’s xenotransplant team, noted that the recipient remains hospitalized for ongoing monitoring and testing. Chinese media have identified the patient as a 69-year-old woman who was diagnosed with kidney failure eight years ago.
Wang also highlighted the team’s work on pig liver transplantation, reporting in the journal Nature that a pig liver transplanted into a brain-dead person remained viable for 10 days without early signs of rejection. The liver produced bile and albumin—essential for organ function—though at lower levels than a human liver.
“The pig liver demonstrated some functional capacity in a human being,” Wang stated, suggesting that such transplants could one day provide temporary support for failing human livers.
The liver presents unique challenges for transplantation due to its complex role in removing waste, breaking down nutrients and medications, fighting infections, storing iron, and regulating blood clotting.
Last year, U.S. surgeons at the University of Pennsylvania explored a similar concept by externally attaching a pig liver to a brain-dead patient to filter blood, akin to kidney dialysis. The U.S.-based biotech firm eGenesis is also investigating this approach.
In the Chinese experiment, Wang’s team implanted the pig liver without removing the brain-dead patient’s own liver. While this method raises some scientific questions, experts believe it represents a meaningful step forward.
“That clouds the picture,” said Dr. Parsia Vagefi, a liver transplant surgeon at UT Southwestern Medical Center who was not involved in the research.
“It’s hopefully a first step, but like any good research, it raises more questions than answers.”
