4 min readKochiOct 23, 2021 11:41 AM IST
First published on: Oct 22, 2021 at 11:34 AM IST
On October 19, USA Today reported that surgeons from New York have successfully transplanted a pig kidney into a brain-dead human. The team from NYU Langone Health used the kidney from a genetically engineered pig and transplanted it into a deceased donor. The function and acceptance of the new kidney were studied for 54 hours.
Dr. Robert Montgomery, who led the surgical team, told reporters that the kidney began functioning and producing large amounts of urine within minutes of being connected to the person’s blood vessels. He added that the creatinine which is cleared from the blood by the kidney dropped from 1.9 to 0.8 demonstrating that the kidney was functioning optimally. Dr Montgomery is the Professor and chair of the Department of Surgery at NYU Langone Health and the Director of its Transplant Institute.
If found compatible in the long run, this process of Xenotransplantation, or transplanting organs between different species, could help provide an alternative and additional supply of organs for people facing life-threatening diseases.
Why a genetically engineered pig?
The transplant conducted on September 25, used a kidney that was obtained from a pig that had undergone editing to knock out a gene that codes for a sugar molecule called Alpha-gal. Alpha-gal is not normally found in humans and this molecule can elicit a devastating immune response in humans.
The pigs with this gene alteration are called GalSafe pigs and have been FDA approved for human use for those who have pork allergies and also for use in pharmacology. These pigs have been well studied and have passed various levels of regulatory scrutiny.
Dr Montgomery added that though primate organs are more compatible with humans, pigs are easier to genetically modify. They also breed better with large litter, grow faster, and are less likely to transmit infections. The size of their organs is also similar to ours.
Did they transplant the pig kidney inside the human body?
No, the kidney was attached to blood vessels in the upper leg, outside the abdomen. It was covered with a protective shield for observation.
Dr Montgomery explained that the kidney remained pink and well-perfused during the 54 hours study period. Biopsies taken every 12 hours and viewed under the microscope showed no evidence of rejection and no indication that harmful antibodies from human blood were attacking the kidney.
He added that the genetic modification of the single sugar molecule was responsible for preventing rapid rejection. The team did use a few FDA-approved traditional immunosuppressant drugs to prevent other types of rejections.
Newsletter | Click to get the day’s best explainers in your inbox
Why is this work so important?
“The traditional paradigm that someone has to die for someone to live is never going to keep up with the ever-increasing incidence of organ failure. The need for organs will always exceed the supply. If human organs are imagined as the fossil fuels of the organ supply, then pig organs are the wind and solar — sustainable and unlimited,” said DrMontgomery.
He added that more studies are needed for a longer duration to fully understand the compatibility in the long run. But he is confident that we can see a pig to living human kidney transplant within a couple of years. He adds that in about 10 years we will be ready to transplant heart, lung, and liver from pigs.
In this September 2021 photo provided by NYU Langone Health, a surgical team at the hospital in New York examines a pig kidney attached to the body of a deceased recipient for any signs of rejection (Joe Carrotta/NYU Langone Health via AP) 
Share
