22 THENEWYORKER,FEBRUARY28, 2022
was told about a field that would help
a hundred times more patients. “That
was the first fish thrown at me,” Mo-
hiuddin told me. He began research
work transplanting organs from ham-
sters to rats. “And, since then, I have
not looked back.”
There were long periods when fund-
ing for xenotransplantation research
seemed almost nonexistent. Mohiuddin
used to work at the National
Institutes of Health. “When
we underwent the external
review, which happens every
five years, they said what we
were doing was a waste of
time and that we should be
shut down,” he said. He se-
cured outside support from
Revivicor. Its C.E.O., Mar-
tine Rothblatt, has a daugh-
ter with pulmonary arterial
hypertension, and the company has
funded research on lung xenotransplan-
tation. At his lab’s next external review,
Mohiuddin said, the assessment was
glowing. It’s difficult for him to explain
to others, even to his wife of nearly thirty
years, exactly what he does. He says he
asked her just to believe in him. “This
was not an easy road,” he said. “There
were many occasions where I thought,
Did I make the right decision?” Mohi-
uddin’s work eventually led to transplants
of pig hearts into baboons; after nine
hundred and forty-five days, the baboons
were still thriving. This work helped per-
suade the F.D.A. to approve the recent
heart transplantation.
Pigs are a preferred xenotransplanta-
tion animal for several reasons: their cir-
culatory system is similar to the human
one, their organs are about the right size,
they grow up fast, they breed easily, and,
well, although they’re as sweet and
emotional as our pet dogs—and often
smarter—they aren’t closely related to
us. Mohiuddin, however, is a religious
Muslim. On his drive to and from work,
he typically listens to the Quran and calls
his mother, who lives in Karachi. “For
me, as a Muslim, of course, pork is a big
no-no,” he said. “We don’t eat pork or
talk about pork.” He encountered some
resistance from his family when he began
to work with pigs. Mohiuddin said, “I
talked to religious leaders—not only
Muslim leaders but also Jewish and
Christian leaders—and the consensus
was that saving lives takes precedence
over everything. That is what I base my
belief on—that what I am trying to do
will help save lives.”
Using baboons in scientific research
is itself anathema to many people. Pro-
testers sometimes demonstrated outside
the N.I.H. when Mohiuddin worked
there. His current lab has no direct en-
trance from outside the building, and
there is security. In 1984, a
baboon heart was trans-
planted into Baby Fae, an
infant with congenital heart
defects. Baby Fae lived for
only twenty days afterward.
One reason for the rejec-
tion was an unavoidable
blood-type incompatibil-
ity—there were no Type O
baboons available. The doc-
tor who performed the pro-
cedure, Leonard Bailey, stated, regard-
ing the choice of a baboon, that he did
not believe in evolution. The year after
Baby Fae’s procedure, Bailey transplanted
a human heart into a four-day-old in-
fant: Eddie Anguiano, known as Baby
Moses, who in 2014 visited the man
who had transplanted his heart.
In the late nineteen-eighties, Jane
Goodall gave a talk to an international
congress on xenografts. “They were all
talking happily about breeding pigs for
xenotransplant, dogs, and so on,” Good-
all said. “I felt like an alien in a world
full of people with no empathy.” The
audience was moved by her speech; ba-
boons are now hardly, if ever, used as a
source of organs, though they are still
used in research. Mohiuddin has been
celebrated and criticized in Pakistan,
where organ transplantation from dead
people is relatively recent and rare.W
hen David Bennett, Jr., visited
his father after the transplant,
David, Sr., in terrible pain, said desper-
ately, “I can’t take this anymore.” By the
end of the day, the pain medications
were working. David, Jr., said, “He was
able to say thank you to the doctors.
That was a huge sigh of relief and peace
to everyone.”
After the surgery, Griffith and Mo-
hiuddin had two worries that they were
trying to balance: rejection and infec-
tion. Immunosuppressants could stave
off rejection, but they left Bennett vul-nerable to infection. Early on, an ab-
dominal infection required an additional
surgery to clear. Later, Bennett had an
unusual response to one of the immu-
nosuppressants, causing his white-blood-
cell count to fall perilously low; his med-
ications were changed. The heart was
beating too powerfully for its fragile
new owner, and it had to be chemically
slowed. By the end of day eighteen, Ben-
nett had outlived the first human-heart-
transplant patient. By the end of day
twenty-one, he had survived longer than
Baby Fae. That day, he remembered to
wish Griffith a happy birthday. He was
able to speak to his son on the tele-
phone, something he had not been strong
enough to do for the ten days before
the transplant. “My dad wants to go
home,” David, Jr., said. “He wants to see
his dog, Lucky.”
Bennett had been on a heart-lung
machine for months before the trans-
plant, leaving him very weak. Even
learning to stand on his own again would
take time. The transplants in Mohiud-
din’s lab had been into young, healthy
baboons; this transplant was a differ-
ent experiment altogether. But, Mohi-
uddin noted, “we also know so much
more about how Mr. Bennett is doing
than we can ever know in the lab.” Grif-
fith said that in the early days, when he
went to check on Bennett, he’d often
find ten experts outside his room, col-
laborating on his care: “There’ll be two
infectious-disease specialists, a trans-
plantation pharmacist, an I.C.U. nurse.
It’s such a team effort—everyone wants
to contribute.”T
ransplants of human organs and of
pig organs may seem like very dif-
ferent procedures, but the problem of re-
jection is the central issue in both cases.
Your body decides what is alien and what
is self. If you get a tiny splinter, your body
will likely mount an inflammatory reac-
tion that extrudes it over time. If you get
infected by a virus, your immune system
will attack it.
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evade detection, because it camouflages
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our own. In a disease such as lupus or
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