Xenotransplant transplant patient died from receiving a heart infected with swine virus
The version used in Maryland came from a pig with 10 gene modifications Developed by Revivicor, a subsidiary of United Therapeutics.
Next Promising trials of such pig organs in baboonsThree US transplant groups have launched the first human studies starting in late 2021. Surgeons at New York University and the University of Alabama have attached pig kidneys to brain-dead people, but the University of Maryland went a step further when Griffith sewed pig hearts. into Bennett’s chest in early January.
The transmission of the virus from pigs to humans is already a concern – some fear that a vehicle transplant could not cause a pandemic if a virus adapts inside a patient’s body and then spreads. to doctors and nurses. The concern may be severe enough to require lifelong follow-up of the patient.
However, the specific virus found in Bennett’s donor heart is not thought to have the ability to infect human cells, said Jay Fishman, a transplant infection specialist at Massachusetts General Hospital. said. Fishman thinks there is “no real risk to humans” that it will spread further.
Instead, the problem is that cytomegalovirus in pigs is implicated in responses that can damage organs and patients — with dire outcomes. Two years ago, for example, German researcher reported that pig hearts transplanted into baboons survived for only a few weeks in the presence of the virus, while uninfected organs could survive for more than half a year.
The researchers said they found “incredibly high” levels of the virus in pig hearts taken from baboons. They suggest that the virus may disappear not only because the baboon’s immune system is suppressed with the drug, but also because the pig’s immune system is no longer there to control the virus. “It looks like the same thing could happen in humans,” they warned at the time.
Joachim Denner of the Institute of Virology at the Free University of Berlin, who led that study, says the solution to the problem is more precise testing. The American team seems to have examined the virus in the snout, but it is often lurking deeper in the tissues.
“It’s a latent virus and it’s hard to detect,” says Denner. “But if you examine the animal better, that’s not going to happen. The virus could be detected and easily eliminated from the pig population, but unfortunately they did not use a good test and did not detect the virus, and this is why. The donor pig was infected, and the virus was transmitted through the transplant.”
Denner says he still thinks the test is a “huge success.” For example, the first human-to-human heart transplant, in 1967, lasted only 18 days, and two years later, a heart transplant in Germany lasted only 27 hours.
Denner said that Bennett’s death cannot be blamed solely on the virus. “This patient is very, very, very sick. Don’t forget that,” he said. “It’s possible the virus played a part, but that’s not the only reason.”
Cause of death?
Bennett’s cause of death is important, because if his heart was damaged as a result of his immune rejection, researchers may need to go back to the drawing board. Instead, it is now expected that companies like United Therapeutics and eGenesis, or the academies that work with them, will launch clinical trials of their pig organs within a day or two. five.
Bennett was offered a pig heart after Griffith applied to the US Food and Drug Administration for a special license to test animal organs in a one-time transplant. He was considered a good candidate for the audacious endeavor as he was dying of heart failure and was ineligible for a scarce heart transplant due to a history of disregarding medical advice.