Groundbreaking Pig Liver Transplant Marks New Era in Medicine

A team of medical professionals in China has achieved a significant milestone in transplant medicine by successfully implanting a pig liver into a human patient. This landmark procedure, described as a “pivotal step forward,” represents the first time a genetically modified pig liver has been used for therapeutic purposes in a living human.

The patient, a 71-year-old man, had been suffering from irreversible liver scarring due to a hepatitis B infection and liver cancer, making him ineligible for a traditional human liver transplant. Following the procedure, he lived for 171 days before succumbing to complications.

Details of the Procedure

The groundbreaking transplant involved an “auxiliary graft” from a genetically engineered Diannan miniature pig. Researchers had modified the pig’s genes to enhance compatibility with human biology. Initial assessments indicated that the graft functioned effectively for the first month. However, by day 38, the patient experienced complications associated with the transplant, specifically a condition known as xenotransplantation-associated thrombotic microangiopathy (xTMA).

Although treatment addressed the xTMA, the patient ultimately passed away, highlighting both the potential of xenotransplantation and the challenges that remain. Dr. Beicheng Sun, the lead investigator, stated, “This case proves that a genetically engineered pig liver can function in a human for an extended period. 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.”

Implications for Future Transplants

Experts view this development as a critical advancement in hepatology. Dr. Heiner Wedemeyer, co-editor of the Journal of Hepatology, commented, “This report is a landmark in hepatology. It shows that a genetically modified porcine liver can engraft and deliver key hepatic functions in a human recipient.” He emphasized that while the procedure opens new pathways for treating patients with acute liver failure and hepatocellular carcinoma, significant biological and ethical challenges persist.

Xenotransplantation, the process of transplanting organs from animals to humans, has faced hurdles related to immune rejection for over four decades. Pigs have emerged as the most promising donor animals due to their organ size and genetic similarities to humans. Recent advancements in gene-editing technology, combined with improved methods to suppress the human immune response, have generated optimism regarding the future of these transplants.

This case builds upon previous efforts in xenotransplantation, including the first heart transplant from a genetically modified pig, performed at the University of Maryland Medical Centre in 2022. The recipient, David Bennett, passed away two months post-surgery. Similarly, another patient, Richard Slayman, underwent a kidney transplant at Massachusetts General Hospital last year and died nearly two months later.

As research continues, the medical community remains hopeful that further developments in xenotransplantation can lead to safe and effective treatments for patients facing severe organ failure, marking the beginning of a new era in transplant medicine.