For the first time ever, a kidney from a genetically modified pig has been transplanted into a human without triggering hyperacuter rejection by the recipient's immune system.
The surgery carried out at NYU Langone Health in New York City on September 25th involved a brain dead patient on a ventilator with signs of kidney dysfunction, whose family had permitted the three-day experiment for the sake of advancing science.
The researchers kept the pig kidney outside of the patient's body to observe and check it was doing its job during the operation. That is, filtering out waste products from the blood and producing urine.
The kidney made "the amount of urine that you would expect" from a transplanted human kidney, said transplant surgeon Dr Robert Montgomery, who led the study.
Differences
Humans and primates differ from other animals in that they lack an enzyme, alpha-gal (alpha 1,3 galactosyltransferase), that places a particular branched sugar group on the animal's cell surfaces.
The kidney was joined to blood vessels on the top of one of the patient's legs so that Montgomery's team could observe it and take biopsy samples.
Montgomery said that the recipient's abnormal creatinine level -- an indicator of poor kidney function -- returned to normal after the transplant.
The genetically modified pig, dubbed GalSafe, was developed by United Therapeutics Corp's Revivicor unit. The US Food and Drug Administration approved it in December 2020 as a potential source of human therapeutics.
