In March this year, patients who underwent a pig heart transplant died Now, according to the surgeon who performed the operation, the heart used for the operation was found to be infected with porcine virus SwineHealth. Org reported that the virus found in the test is called porcine cytomegalovirus (PCMV), which mainly infects pigs, but it has also been found in humans. Nevertheless, whether human cells can be infected by PCMV is still unknown.
According to a statement from the University of Maryland School of medicine, it is unclear whether the virus caused the patient's death or because the patient's heart was in an advanced stage of failure before transplantation. The death of this patient is still under investigation.
Dr. Bartley Griffith took charge of the first heart transplant in January 2022, and everything seems to be going well after the operation.
The pig heart works in recipient David Bennett. According to information regularly released by the Maryland hospital, Bennett seems to be slowly recovering. In February, the hospital also released a video of Bennett watching the super bowl on his hospital bed and with his physiotherapist.
Unfortunately, Bennett died on March 8. Doctors were unable to give an exact cause of death, saying only that his condition began to deteriorate a few days before his death. It is reported that Bennett is 57 years old.
"We are saddened by Bennett's departure," Griffith said in a statement. "Facts have proved that he was a brave and noble patient and fought until the end."
Bennett's genetically edited pig heart survived significantly longer than the last milestone of allogeneic transplantation - FAE, a dying baby in California, lived 21 days after transplanting a baboon's heart in 1984.
Shortage of donors
The demand for another organ source is enormous. Last year, more than 41000 transplants were performed in the United States, setting a record - including about 3800 heart transplants. But more than 106000 people are still on the waiting list across the United States, as thousands die each year before getting organs, and thousands have never even been on the list.
Dr Jayme Locke, of the University of Alabama at Birmingham (UAB), said: "organ shortage is actually a crisis that cannot be alleviated. We have never had a real solution." It is reported that his team will start clinical trials of pig kidney transplantation this year.
What is allogeneic transplantation
Animal to human transplantation is called allogeneic transplantation. For decades, they have tried, but failed, because people's immune system attacks foreign tissues almost immediately. But scientists now have new technology to edit pigs' genes, which makes their organs more human like.
Dr. David kaczorowski of the University of Pittsburgh Medical Center said the series of pig experiments in the past year was a big step forward.
As a heart transplant surgeon, kaczorowski helped pave the way by testing pig organs in non-human primates, but said he could learn something only by transplanting them into humans.
Pigs have long been used in human medicine, including pig skin transplantation and pig heart valve implantation. But transplanting an entire organ is much more complex than using highly processed tissue.
The future of allogeneic transplantation
Dr. Robert Montgomery of the langney health center at New York University warned that scientists still have a lot to learn about how long pig organs can survive and how to best change their genes.
"I think different organs will need different genetic modifications," he said in an email to the associated press
In addition, researchers must solve some practical problems, such as how to minimize the time to send pig organs to their destination. UAB housed the modified pigs in a sterile facility in Birmingham and equipped a space similar to an operating room to remove organs and prepare for transplantation.
Organ rejection, infection and other complications are risks for any transplant recipient. Experts hope the Maryland team will publish the exact response of Bennett's body to the pig's heart in the medical journal as soon as possible.
Dr Muhammad mohiuddin, scientific director of the animal to human transplantation program at the University of Maryland, said: "from Bennett's experience, we have gained valuable insights that the transgenic pig heart can work well in the human body, while the immune system is fully suppressed."