"A 57-year-old Maryland man who
survived for two months with a heart transplanted from a genetically altered
pig carried signs of a virus that infects the animals, according to the surgeon
who performed the first-of-its-kind procedure.
The disclosure bolsters one of the
most pressing objections to animal-to-human transplants, which is that
widespread use of modified animal organs may facilitate the introduction of new
pathogens into the human population.
The presence of viral DNA in the
patient may indicate an infection that contributed to his sudden deterioration
and death on March 8, Dr. Bartley Griffith, a transplant surgeon at the
University of Maryland School of Medicine, said during a presentation to the
American Society of Transplantation.
Dr. Griffith’s comments were first reported by MIT
Technology Review.
The pig was genetically modified so
that its organs would not prompt rejection by the human immune system. The heart
was provided to the patient, David Bennett Sr., by Revivicor, a regenerative
medicine company based in Blacksburg, Va.
Company officials declined to
comment on Thursday. University officials said the animal had been screened for
the virus, called porcine
cytomegalovirus. But the tests pick up only active infections, not latent
ones in which the virus may hide quietly in the pig’s body.
Mr. Bennett’s transplant was
initially deemed successful. He did not show signs of rejecting the organ, and
the pig’s heart continued to function for well over a month, passing a critical
milestone for transplant patients.
A test indicated the presence of
porcine CMV in Mr. Bennett 20 days after the transplant, but at such a low
level that Dr. Griffith said he thought it might have been a lab error. At 45 days after the surgery, Mr. Bennett
became acutely ill, and subsequent tests showed a precipitous rise in levels of
the virus, Dr. Griffith said.
“So we started thinking that the
virus that showed up very early at Day 20 as just a twinkle started to grow in
time, and it may have been the actor — it could have been the actor — that set
this all off,” Dr. Griffith told other transplant scientists.
Mr. Bennett’s health deteriorated abruptly 45 days after the
surgery, he said.
“At Day 45, he looked really funky,” Dr. Griffith said.
“Something happened. He looked sick. He lost his attention. He wouldn’t talk to
us. He lay in bed breathing hard, and was kind of warm.” Mr. Bennett died on
March 8.
The heart transplant was one of
several groundbreaking transplants in recent months that offer hope to the tens
of thousands of patients who need new kidneys, hearts and lungs amid a dire
shortage of donated human organs.
But the prospect of unforeseen
consequences — and particularly the potential introduction of an animal disease
into the human population — may dampen enthusiasm for the use of genetically
modified organs.
Many scientists believe that the
coronavirus pandemic originated with a virus transmitted from an animal, as yet
unidentified, to people in China.”
One thing is to get the virus during
a lifesaving surgery. Completely different thing is to get the virus, snacking
on a bat. People, could you stop eating the bats, please?
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