According to scientists who performed the groundbreaking procedure, genetically modified pig liver implanted in brain-dead patients appeared to function successfully in the body for 10 days.
Surgery at a Chinese hospital last year is thought to indicate that the pig's liver was first implanted into a human. It is to increase the prospect of pig liver acting as a “crosslinked organ” for patients on the waiting list for transplants and support liver function while their organs are regenerating.
Professor Lin Wang, who headed the trial at Xijing Hospital in Xi'an, said:
This advancement is the latest in a series of transplants involving pig organs since 2022. Surgeons in the US and China are transplanting pigs heart, kidney and Thymus To a small number of patients. He died within a few months, but initially the severe illness meant that it was unknown whether the transplant was a factor. However, others recovered well and left the hospital.
The latest procedure was performed in a 50-year-old man diagnosed with brain death after a severe head injury. The patient's own liver was intact and in the surgery that took more than 10 hours, organs collected from GMO-modified Bama miniature pigs were placed in the blood supply as additional livers.
Pigs had six genetic modifications intended to prevent immune rejection. These were introduced into genes that contribute to sugar production on the surface of pig cells that the human immune system attacks, and genes expressing human proteins to “humanize” the liver.
After implantation, pig livers showed signs of function, including the production of bile, which helps to break down fat in the digestive system.
“There was good compatibility evidence, but it's really exciting,” said Peter Friend, a professor of transplants at Oxford University. “Using pig organs usually results in harsh rejection, so it's made into stone within minutes.”
The team behind the advance Explained in the journal Naturesaid it was not clear whether the liver could fully support the patient, given that he had an existing liver and that the liver was removed 10 days later at the request of his family. “We didn't know if pig livers could support patients with severe liver failure,” Wang said.
Even if pig livers only partially replace liver function, they may still be valuable as “bridge” implants. A friend said the “elegant surgical plumbing” used by the team means this could be a relatively simple procedure.
“They basically slot the liver… into the main artery that runs from the legs towards the heart,” he said. “It's safer and blames much more for complications and what you can remove when you're not needed.”
“We've seen a lot of people who have had to go through the heart xenotransplantation program,” said Professor Muhammad Mohiudin, director of the University of Maryland's Cardiac Xenotransplant Program.
“It can be used as a bridge until the human liver is available for transplantation or until it can be used as partial support until the liver regenerates. I firmly believe this will work.”
