A monkey that received a kidney transplant from a pig has survived for two years, reports eGenesis of Cambridge, Mass. in an article published in Nature, a scientific journal.
Wenning Qin, and her team report what she called a proof of concept for genetically engineered pig organs supporting life in monkeys.
Testing the organs in a non-human primate is a necessary step before a possible human clinical trial.
Mike Curtis, chief executive officer for eGenesis, told reporters he views the pig organs as the only near-term, viable solution to humanity's organ shortfall. "We just don't have enough kidneys," he said.
eGenesis grew genetically-engineered Yucatan miniature pigs from germ cells (egg or sperm) to make their organs more compatible with a monkey.
Church said human germline cells — those that produce egg and sperm — currently can't be engineered the way pigs ones can. But he said it "won't be out of the question" to one day engineer animal organs to prevent rejection by a specific person.
The kidney study included three major changes involving 69 genomic edits in total.
First, scientists knocked out the function of three sugars thought to promote rejection. They also made the organ more human-like so the primate's immune system would be more welcoming, with eventual suitability for patients in mind. The last step was inactivating copies of a porcine retrovirus gene that's considered a risk to transmit to humans.
The most human-like kidney grafts survived much longer than those with just the sugar changes, 176 days compared with 24 days. One animal survived two years or 758 days.
Curtis called it the longest graft survival between species and the most advanced porcine donor.
Tests showed the monkeys had good kidney function. Infections and surgical complications killed more of them than rejection, the researchers said.
Consistency of survival is important. Curtis said U.S. regulators are looking for several transplanted monkeys to make it a year before considering early-stage trials in human subjects.
They used Yucatan miniature pigs in their research because they are about the same size as humans.
A couple of weeks ago, Laurence Faucette received a pig’s heart at the University of Maryland Medical Center (UMMC), becoming the second person to get a pig’s heart transplant at that centre.
The first was David Bennett in January of 2022, who died of issues not related to the transplant.
