For the first time, a pig kidney has been transplanted in a human, without immediately rejecting the organ. Doctors in New York used a pig kidney whose genes had changed so that they no longer contain the molecule that leads to direct rejection in the human body.
“What they probably did is bring certain human proteins into the pigs gene. If an organ is transplanted, it is not immediately recognized as foreign by the immune system and is not repulsed,” says Ian Alwayn, professor of transplant surgery at Leiden University Medical Center.
He calls it “groundbreaking” that pigs organs have now been transplanted for the first time in a human being. “This has been successful in monkeys before, but this is a breakthrough.”
Kidney outside the body
The person who received the organ is a brain dead patient with renal failure. Her family agreed to the experiment before she was to be taken from the ventilator, writes Reuters news agency. The kidney was attached to her blood vessels and kept out of her body so the researchers could see what happened to it.
According to the study leader, the test results of the transplanted pig organ looked “pretty normal” and the kidney made the amount of urine you would expect from a transplanted human kidney. The experiment was terminated after 54 hours by switching off the ventilation, after which the woman died.
Transplant surgeon expect pigs may be the solution to the large shortage of donor organs in the future. In addition to kidneys, the animals could also provide hearts, livers and other organs. In the Netherlands, more than 1300 people are waiting for a donor organ according to figures from the Dutch Transplant Foundation.
According to Alwayn, the technique is still in its infancy and can take a few more years before it gets this far. “First, it must be determined that this can be safe, through a human trial.”
But science isnt there yet, says Alwayn, and the corona pandemic has played a part in that. “The pandemic has fueled fears of germs moving from animal to human. And by transplanting an animal organ to a human body, you create a breeding ground for dangerous germs. With new genetic techniques, you can disable certain viruses, but you cant turn off the entire genome. Because what youre left must be viable as well.”
Apicids are more suitable for growing organs, because the monkey is closer to humans in terms of properties than the pig, says Alwayn. However, according to the professor of pigs are more accepted as an organ donor, because we also use the animal frequently for consumption.
Pigs are also interesting to scientists because pig organs are similar in size to that of humans, and the animals often get a lot of piglets after a short gestation period.
No spare parts
Animal welfare organizations criticise the use of pigs organs. For example, action group PETA, which operates worldwide, writes: “From an ethical perspective, PETA has always opposed the use of live animals as a repository for human spare parts. Animals are not spare parts.”
Alwayn stresses that science prefers not to use animals. “If we can solve the problems in other ways, for example through prevention and other techniques, it is preferable to breeding animals for the use of organs.”
He hopes the results of the US research will be published quickly. “The details about the organ, whether there was an infection, how it looked microscopic, thats all important. But it is certain that this is groundbreaking.”