12 March/April 2022PHOTO^ ILLUSTRATIONBYALYSE^ MARKEL^ USING^ GETTYIMAGES3
Bioengineering
// B Y K I M B E R L Y H I C K O K //I
N A GROUNDBREAKING 2021 EXPERIMENT,
surgeons from NYU’s Langone Health con-
nected a genetically modified pig kidney to the
blood vessels of a brain-dead organ donor on
life support. The pig’s organ filtered waste from
the woman’s blood and produced urine, just like
a human kidney, for the entire 54-hour experi-
ment. This first-of-its-kind procedure could signify
pig kidneys as a transplant option for more than
90,000 Americans waiting for such an operation.Transplanting organs is difficult, because our
immune system is programmed to destroy any-
thing it doesn’t recognize as native to the body.
Animal-to-human transplants are extra challeng-
ing because most mammals, including pigs, carry
a gene that allows their body to make a sugar found
in cell membranes called alpha-gal. But that gene is
inactivated in some species of primates, including
humans. Our immune system therefore sees alpha-
gal as an intruder and produces natural antibodiesSomeday, a Pig-to-
Human Organ Transplant
Could Save Your Life
Kidneys (above)
aren’t the first
pig part to enter
a human body.
Doctors routinely
transplant pig
heart valves into
human patients.