From liver to kidney: Chinese scientists pass another milestone in pig-to-human organ transplants

“It functions well in the recipient’s body and produces normal urine.”

The transplant was performed on March 25, just a few weeks after the team performed the pig liver transplant. In both cases, the patients’ families agreed to the procedure to help advance medical science, the university said.

Kidney transplants are the only cure for end-stage kidney disease. Although more than one million patients in China suffer from the disease, only 10,000 transplants are performed each year, the Department of Urology at the Air Force Medical University said in a WeChat post last week.

However, xenogeneic transplants – the transplantation of an organ or tissue from one species into another – could offer a solution.

Pig organ transplants in China and the US open an ethical can of worms

Pigs are used for these surgeries because they have a similar metabolism and organ size to humans. Although monkeys are the most similar species to humans, the US Food and Drug Administration has banned the use of their organs because of the higher risk of spreading the disease.

Medical teams in both China and the US have tested pig organ transplants on brain-dead patients who need a ventilator to survive, with the consent of their families, before trying the technology on other patients.

“Research on xenogeneic organ transplantation has entered an accelerated period,” said Dou Kefeng, one of the leaders of the transplant team, according to the publication.

Such transplants could provide “a very conceivable solution” to the shortage of organs for transplant, if only by buying time for patients waiting for human organs, Dow said.

During the transplant, the renal artery of the pig’s kidney is connected to the patient’s external iliac artery, which provides the blood supply to the legs.

Once blood flow was restored and the kidney began producing urine, the patient’s own kidneys were removed, the university said.

To reduce that risk, scientists used CRISPR/Cas9 gene-editing technology to add two human genes to the pig used in the transplant and remove three pig genes that can cause hyperacute rejection, the university said.

Last month, a team at Massachusetts General Hospital in the United States made history with the first transplant of a gene-edited pig kidney into a non-brain-dead patient with end-stage renal disease.

The 62-year-old recipient suffered an episode of acute rejection eight days after the transplant when white blood cells invaded the organ, according to US medical website STAT news.

However, this type of rejection is common in human kidney transplants, and the report said the patient was successfully treated with steroids and a drug to deplete white blood cells.

Doctors in China have been monitoring the recipient of their kidney for signs of rejection or infection, the university said.

The team’s feat last month with a pig liver, which also functioned normally for 10 days until it was removed, presented a greater challenge than their recent success because human livers are more complex than kidneys both in terms of both in function and in structure, which means that they cannot be completely replaced by a pig organ.

Chinese team grows humanized kidneys in pigs, raising hopes and ethical concerns

Before its human trials, the transplant team also transplanted pig organs into monkeys in 2020, the university said.

Qin said the transplant team’s work could pave the way for future transplants that could help the millions waiting for life-saving surgeries.