In a major breakthrough for organ transplant, scientists in the US were successful to temporarily attach a pig's kidney to a human body. The kidney functioned well without triggering a strong response from the human body's immune system. The research for using animal organs for live saving transplants has been going on for decades now.
However, using pigs for organ-transplant wasn't easy since a sugar in pig cells, foreign to the human body, causes immediate organ rejection, the Associated Press reported. To make the kidney compatible for human body, scientists used a a gene-edited animal, engineered to remove the sugar in order to avoid the attack from immune system.
The procedure was done at NYU Langone Health in New York City and the recipient was a brain-dead patient with signs of kidney dysfunction, the Reuters reported. The patient's family had consented to the experiment before being taken off life support.
During the procedure to check the working of a kidney from genetically-altered pig in human body, surgeons fitted the kidney to a pair of large blood vessels outside the body of a deceased recipient. The surgeons observed the process for two days and the kidney successfully filtered out the waste and produced urine. the immune system did not attack the new organ.
The doctors leading the experiment said the organ started functioning normally with no immediate rejection.
On the functioning of transplanted kidney, the doctors said it "looked pretty normal".
"The kidney made the amount of urine that you would expect from a transplanted human kidney and there was no evidence of the vigorous, early rejection seen when unmodified pig kidneys are transplanted into non-human primates," transplant surgeon Dr Robert Montogemery, who led the study said.
In 20th century, scientists were trying to transplant organs from baboons to human bodies. In fact, in 1984, Baby Fae, a dying infant lived for 21 days on a baboon heart. The baby became the first infant subject of a xenotransplant, animal-to-human organ transplant.
However, there was not much success on this front, compelling the scientists to think of other animals for the transplant. From primates, they moved on to pigs and tried altering their genes to make their organs compatible to human bodies.
The pig with gene modifications, dubbed GalSafe, was developed by United Therapeutics Corp's (UTHR.O) Revivicor unit. It receieved green flag from the U.S. Food and Drug Administration in December 2020, for use as food for people with a meat allergy and as a potential source of human therapeutics, according to Reuters.
Using pig in the research came with lesser ethical obligations since the animal is usually raised for food, unlike apes. Its organs are comparable to those of humans, have large litters and short gestation periods.
In the next couple of years, this kind of kidney transplant experiment could pave way for trials in patients with end-stage kidney failure, Dr Robert Montgomery, who led the research said. The trials, he said, might test the approach as a short-term solution for critically ill patients until a human kidney becomes available, or as a permanent graft.
