In a world-first medical feat, Chinese doctors have successfully transplanted a genetically modified pig liver into a human patient—an unprecedented milestone in the field of xenotransplantation.
The recipient, a 71-year-old man suffering from end-stage liver disease caused by hepatitis B and liver cancer, was not eligible for a traditional human liver transplant. Researchers say the experimental procedure gave him nearly six additional months of life following the surgery.
“This case proves that a genetically engineered pig liver can function in a human for an extended period,” said lead researcher Dr. Beicheng Sun from the First Affiliated Hospital of Anhui Medical University in eastern China. “It is a pivotal step forward, demonstrating both the promise and the remaining hurdles, particularly regarding coagulation dysregulation and immune complications, that must be overcome.”
Published in the Journal of Hepatology, the study details how scientists implanted an “auxiliary graft” from a specially engineered Diannan miniature pig. The pig had been genetically modified to make its organ more compatible with the human body. For over a month, the transplanted liver performed vital metabolic and synthetic functions successfully.
However, complications arose on day 38 due to a condition known as xenotransplantation-associated thrombotic microangiopathy (xTMA)—a clotting disorder unique to such transplants. Though doctors managed to stabilize the condition by removing the pig liver graft, the patient died 171 days after the operation.
“This report is a landmark in hepatology,” said Dr. Heiner Wedemeyer, co-editor of the Journal of Hepatology, in an accompanying editorial. “It shows that a genetically modified porcine liver can engraft and deliver key hepatic functions in a human recipient. At the same time, it highlights the biological and ethical challenges that remain before such approaches can be translated into wider clinical use.”
Xenotransplantation—the transfer of organs or tissues between species—has long been a scientific goal. Pigs have become the preferred donor animals due to their organ size, genetic similarity to humans, and advancements in gene-editing technologies.
Previous pig liver transplants had only been conducted in brain-dead individuals. This marks the first time a pig liver has been used therapeutically in a living patient.
Scientists have also tested genetically modified pig hearts and kidneys in humans. David Bennett became the first to receive a pig heart in 2022 but passed away two months later. Similarly, Richard Slayman received a pig kidney in 2024 and survived nearly two months after the transplant.
Despite setbacks, experts say this latest liver transplant is a major step toward solving the global organ shortage crisis.
“Xenotransplantation may open completely new paths for patients with acute liver failure, acute-on-chronic liver failure, and hepatocellular carcinoma,” said Dr. Wedemeyer. “A new era of transplant hepatology has started.”
(dpa)
