The procedure is the first of its kind and represents an advance in efforts to determine whether organs from non-human animals can be modified and successfully used in humans in need of transplants.
The 72-year-old recipient, Lawrence Kelly of Pennsylvania, was pronounced brain dead. His family donated his body to the study, which aimed to investigate how well a modified pig heart works in the body of a deceased person.
After Kelly’s transplant in June, the research team repeated the procedure with another deceased recipient, Alva Capuano, 64, of New York, in early July.
Dr. Robert Montgomery, director of New York University’s Langone Transplant Institute, said the procedures allow for a more in-depth study of how well recipients’ bodies tolerate the pig hearts.
“We can do much more frequent observation and really understand the biology and fill in all the unknowns,” he said.
He added that their research is unique because they try to mimic real-world conditions, such as not using experimental devices and drugs.
The researchers are working on publishing additional details of the study.
“He came out a hero”
Researchers traveled out of state to obtain the heart, which had genetic modifications aimed at a number of factors, such as modulating the organ’s growth and reducing the chance that the recipient’s immune system would reject it.
The flight meant the team could replicate the conditions of a typical heart transplant, said Dr. Nader Moazami, surgical director of heart transplantation at NYU Langone Health.
“It was about an hour and 15 minutes flight from New York, which is typical of the distance we take hearts for clinical transplant,” said Moazami, who performed the transplant.
The heart went to Kelly, a Navy veteran who was declared brain dead after a car accident. Kelly’s fiancee, Alice Michael, authorized the donation of his body for research.
“They were going to take his liver and they couldn’t find a recipient. And then New York University called me with this research. And I automatically said yes because I know he would want to do it. He loved helping people,” she said.
“When I was asked, I didn’t have to think twice about it. I just automatically said yes because I knew it was groundbreaking research and I know he would want it. It was hard because I had to wait to bury But in the long run it can help a lot of people.
“He was a hero in life and he went out a hero,” Michael said.
After the transplant, researchers ran tests for three days to track how well the heart was being accepted while the recipient’s body was kept alive using machines, including ventilation.
“No signs of early rejection were observed and the heart functioned normally with standard post-transplant medications and without additional mechanical support,” the medical center said in a press release.
The researchers also said they found no signs of porcine cytomegalovirus (pCMV) infection, which experts fear could pose a barrier to the use of pig organs in humans.
A new method for transplant research
Testing how well an organ transplant works using a deceased person’s donated body is a new method, Moazami said. The first use of this research technique occurred in September, when an NYU Langone team led by Montgomery transplanted a kidney from a genetically modified pig into a deceased human.
While the study represents a step forward, Moazami said, there is still work to do before such a procedure becomes widely available outside of a research setting.
“There is still a long way to go before we move from here to clinical transplantation to support the patient in the longer term,” he said. “There are still many, many, many questions that need to be answered.”
One important limitation was the length of the study, he said; the organ and the recipient were evaluated only 72 hours after transplantation. Also, there may be important differences in how the bodies of deceased people respond to the procedure compared to living people. More research will be needed to determine how transplant recipients will fare in the long term.
“We thought that in 72 hours we could learn all the things that we would have learned if we had extended this a little bit longer,” Moazami said, noting that the short time frame limits the cost of the study and allows the recipient’s body to return to normal. – quickly to his family.
“We thought 72 hours was a reasonable amount of time for our short-term study to find out all the things we needed to know — that three days versus five days versus seven days wouldn’t matter. Does three days versus a month matter? Yes, absolutely. But at this stage that would be very, very difficult to achieve.”
Transplanting animal organs into humans also raises a number of other ethical questions, such as whether the benefits of using a modified pig heart outweigh the risks the patient would face if they waited for a human organ to become available instead.
A personal connection and a new frontier
For Montgomery, the research has a personal side. He is a recipient of a human heart transplant and said the difficulty of securing a transplant is part of what motivates his work.
“During my illness it became clear to me that this paradigm was not working. It’s a failing paradigm and that we need a renewable resource, an alternative source of organs that doesn’t require someone to die so that someone else can live,” he said.
“My whole illness has been about making me aware of the reality of it and changing the way I think, not that it’s not important to keep doing what we’re doing, but we need to move this in a completely different direction. “
Overall, the demand for organ transplants far exceeds the supply of donor organs available in the United States. As of July 7, there are 106,074 people on the organ transplant waiting list and 3,442 on the heart transplant waiting list. An average of 17 people die on the organ transplant waiting list every day.
Moazami suggested that animal transplants may someday be useful in the pediatric setting, where patients may face even greater challenges in getting a timely human organ transplant. Animal organs can be used as a “bridge”, buying time before a more optimal human organ becomes available.
“Perhaps the best way to explore this is to perhaps use it as a bridge to a human transplant, if you will, so that any patient who needs an organ can get that heart with the stipulation that when a human heart becomes available, matches the recipient, we exchange it again,” Moazami said.
Add Comment