Hearts from genetically modified pigs were put into deceased people.
The two recipients were kept alive on ventilators
The New York University researchers reported today that they successfully transplanted genetically engineered pig hearts into two recently deceased patients who were attached to ventilators. The procedures are the latest advancement in the field of animal-to-human transplantation, or xenotransplantation, which has witnessed a flurry of triumphs this year, increasing expectations for a fresh, consistent supply of organs to alleviate shortages.
The only difference between these heart transplants and a standard human-to-human heart transplant, according to the research team, was the organ itself. “Our objective is to incorporate the methods utilized in a regular, daily heart transplant, but with a nonhuman organ that will operate correctly without the assistance of unproven technologies or pharmaceuticals,” said Nader Moazami, head of heart transplantation at NYU Langone Transplant Institute.
The transplants were conducted on June 16th and July 9th, and each recipient was observed for three days. The hearts were working correctly at the time, and there were no signals of rejection from the recipients, who were hooked up to ventilators to keep their bodily processes running semi-regularly even after death. Although the two recipients were unable to donate organs, they were eligible to engage in a whole-body donation for this sort of study.
Revivicor, a biotechnology business that manufactures genetically engineered pigs, provided the two pig hearts (and also funded the research). The pigs underwent ten genetic alterations, four of which were to inhibit pig genes and avoid rejection, and six of which were to introduce human genes.
In early January, a real individual was successfully implanted with a pig heart made by Revivicor at the University of Maryland Medical Center. David Bennett Sr., who had significant heart disease, reacted well to the transplant at first but died of heart failure in March. The precise reason is uncertain, however, infection with a pig virus may have had a role in his death. The pig hearts are meant to be virus-free, but specialists believe they can be difficult to detect.
The NYU team stated that it added new viral screening techniques for its transplants. It also set up an operating room for xenotransplantation, which will not be utilized for any other surgical procedures.
Even if a pig heart has previously been transplanted into a living human, testing transplants on dead patients is still necessary, according to Robert Montgomery, head of the NYU Langone Transplant Institute, at a news conference. “The emphasis is really on learning, researching, measuring, and attempting to truly untangle what is going on with this fresh new, fantastic technology,” he explained. For example, the team was able to perform biopsies on a daily basis. Because the receiver was still alive, the research team at the University of Maryland was unable to investigate the transplant in great detail, he explained.
NYU has also employed brain-dead individuals to try kidney xenotransplantation. NYU revealed this autumn that scientists had successfully linked a pig kidney to the leg of a ventilator patient. The organ was not rejected by the patient’s body, and it continued to operate appropriately after 54 hours of monitoring.
Full clinical trials of xenotransplantation in living persons are currently being planned by research teams. To do so, they’d require clearance from the Food and Drug Administration. Montgomery stated during the press conference that the NYU team’s goal is to prolong the period of time they monitor a transplanted heart in order to collect additional data to guide trials. He believes clinical studies will begin between now and 2025. Revivicor stated in April that it expects to begin clinical trials over the next year or two.
There is still much to learn about xenotransplantation, as well as the ethical concerns of animal-to-human treatments. However, if they are successful, they might provide a new alternative for the thousands of patients on organ transplant waiting lists.
“I feel that xenotransplantation offers the best potential for a renewable, sustainable source of organs so that no one has to die waiting for an organ,” Montgomery said.