Researchers at New York University Langone Health have successfully transplanted two pig hearts into clinically dead patients in the past month, neither heart rejecting the human body over the course of each three-day study. This accomplishment indicates that xenotransplants could potentially counter the shortage of organs available for transplantation.
The NYU Langone Surgical Institute utilized bodies of those who had previously suffered catastrophic heart failure and were kept on life support despite brain death. They completed the two pig heart transplants on June 19 and July 9, each heart beating strongly throughout the study. Neither heart required mechanical or medicinal support post-transplant.
Dr. Nader Moazami, surgical director of heart transplantation at the NYU Langone Transplant Institute, performed the xenotransplants. He spoke to NYU media about the operations and what happened after the pig hearts were transplanted into humans.
“Our goal is to integrate the practices used in a typical, everyday heart transplant, only with a nonhuman organ that will function normally without additional aid from untested devices or medicines,” said Moazami. “We seek to confirm that clinical trials can move ahead using this new supply of organs with the tried-and-true transplant practices we have perfected at the NYU Langone Transplant Institute.”
According to NYU Langone Health, the hearts used for the surgeries were taken from pigs with 10 genetic modifications — four to prevent abnormal organ growth and rejection, and the remaining six to promote the growth of proteins necessary for proper heart function in the human body.
The NYU surgical research team also employed their new infectious diseases protocol to prevent viruses two viruses common to pigs, “porcine cytomegalovirus” and “porcine endogenous retrovirus” from infecting the human body via the transplanted heart. The viruses both potentially cause irreparable damage if present in organ or tissue xenotransplants. For that reason, the operating room used for this study will only be used for future xenotransplantation research, according to NYU Langone Health.
“Other studies have shown that (porcine cytomegalovirus) may be a factor in the success of xenotransplanted organs,” said Dr. Robert Montgomery, the director of the NYU Langone Transplant Institute.
“More sensitive screening methods have been introduced to detect low-level traces of (that virus) in the donor pigs. We have included that additional screening in this heart transplant protocol to give the organ the best chance at long-term survival,” Montgomery said.
Montgomery also spoke on the reasoning behind the use of porcine hearts, explaining that pig organs are similar in size to that of humans and are easier to genetically modify.
“We need a renewable resource, an alternative source of organs that doesn’t require someone to die in order for someone else to live,” Montgomery said to CNN.
“Our greater purpose is to address the organ shortage and provide another option for the more than 100,000 people nationwide waiting on that lifesaving gift,” Montgomery said.
Xenotransplantation has been pointed to as a potential aid to the current organ shortage, as there are now 105,862 individuals waiting for transplants in the U.S., according to the Organ Procurement and Transplantation Network. Of those, 3,427 are waiting for a heart transplant.