Genetically Modified Pig Liver Functions in Human for 31 Days

A genetically modified pig liver has successfully operated outside the human body for 31 days, marking a significant breakthrough in transplantation science and offering new hope for addressing organ shortages in the future.

A Medical Milestone: The First Modified Pig Liver Transplant

In an unprecedented leap for transplantation and xenograft research, a team of physicians successfully transplanted a genetically engineered pig liver into a living human. This pioneering surgery, detailed in the Journal of Hepatology, involved a 71-year-old man suffering from inoperable liver cancer, for whom standard treatments offered no hope.

The Genetic Innovation Behind the Procedure

Rather than fully replacing the diseased organ, clinicians opted for an auxiliary approach: the pig’s liver was implanted to function in tandem with the patient’s own. At the heart of this strategy lay advanced gene editing. Ten genes in the donor pig were precisely modified to reduce immunological rejection, support blood coagulation, and enhance critical metabolic functions.

This innovative application of genetic technology quickly proved its worth. Upon transplantation, the animal organ immediately began producing essential proteins for blood clotting, detoxifying harmful substances, and generating bile. The patient’s condition remained stable for more than a month, with no major infections or organ failures observed.

Unexpected Setbacks and Tragic Outcome

Nonetheless, this groundbreaking attempt was not without severe complications. After 38 days, doctors encountered a rare immune response known as xenotransplantation-associated thrombotic microangiopathy (xTMA), which causes clotting within small blood vessels. Interventions—including administration of eculizumab and plasma exchange—temporarily stabilized the situation. Yet, despite extended periods of improvement, the patient ultimately succumbed to internal bleeding 171 days post-transplant.

Paving the Way for Future Solutions

Despite this tragic ending, experts are heralding the operation as a landmark achievement. It marks the first time that a genetically modified pig organ has demonstrated sustained function in a living person—surpassing prior attempts limited to brain-dead donors.

Several factors explain why this could reshape transplant medicine:

• Expanding treatment options for those on endless waiting lists;
• Providing “bridge” therapies until human organs become available;
• Sparking innovative research into overcoming chronic organ shortages worldwide.

This breakthrough, even in loss, signals renewed hope for thousands awaiting transplants and highlights the transformative potential of science in tackling persistent medical crises.