Scientific breakthrough took place at New York University. There, a group of surgeons grafted the genetically modified organ to the body of a brain-dead woman.
The scientists succeeded temporarily attach a pig kidney to a human body and observed that it began to function, a breakthrough in decades-long quest to one day use animal organs in transplants to save human lives.
Pigs have become the latest research priority in an attempt to address the organ shortage, but there is an obstacle : a type of sugar in porcine cells , foreign to the human body, causes immediate rejection of the organ . The kidney for this experiment came from an animal genetically engineered to remove that sugar and prevent an attack from the immune system..
Surgeons attached the pig’s kidney to a pair of large blood vessels outside the body of a brain-dead recipient so they could observe it for two days.The kidney did what it was supposed to do – filter waste and produce urine – without causing rejection..
” Had an absolutely normal function , ” said Dr. Robert Montgomery , who led the surgical team last month at the Medical Center Langone Health of the University of New York . ” There was not this immediate rejection that we feared .”
This research is ” an important step , ” said Dr. Andrew Adams , of the School of Medicine of the University of Minnesota , and was not part of the investigation. It will reassure patients, researchers and regulatory authorities ” that we are moving in the right direction .”
The dream of animal-to-human transplants – or xenotransplantation – dates back to the 17th century with the failed attempts to use animal blood in transfusions. In the 20th century, surgeons attempted to transplant baboon organs into humans. The most famous case was that of the Baby Fae , who lived 21 days with the heart of a primate of that species .
Without any long-term efficacy and too much public outrage, scientists turned from primates to pigs , manipulating their genes to bridge the gap between species. Pigs have advantages over monkeys and apes. They are raised for food, so using them to harness their organs raises fewer ethical concerns . They also have large litters, short gestation periods, and organs comparable to humans.
This is not the first time that pork parts have been used in humans: Pig heart valves have also been used effectively for decades in humans, the anticoagulant heparin is obtained from pig intestines, pig skin grafts are used for burns, and Chinese surgeons have used pig corneas to restore sight.
In the case of the UNY , the researchers kept the body of a deceased woman operating on an artificial respirator after the family authorized the experiment. The woman wanted to donate her organs, but they were not suitable for a traditional donation. The family thought ” there was a chance that something good would come out of this ,” Montgomery said.
Montgomery himself received a transplant three years ago, a human heart from a donor with hepatitis C. ” I was one of those people lying in an intensive care unit waiting not knowing if an organ would arrive in time, ” he said. Various biotech companies seek to develop pig organs suitable for transplantation in order to reduce the shortage of human organs. More than 90,000 people in the United States are on the waiting list to receive a kidney. Every day 12 of them die in waiting.
The breakthrough is a triumph for Revivicor , a subsidiary of United Therapeutics , the company that manipulated the development of the pig and its cousins, a group of 100 animals raised under highly controlled conditions at a facility in Iowa . These pigs lack a gene that produces alpha-gal , the sugar that causes an immediate attack on the human immune system.
In December, the Administration of Food and Drug ( FDA for its acronym in English) authorized the genetic alteration in Revivicor pigs and considered unfit for human consumption and medical use in humans. However, the FDA said developers need to provide more documentation before pig organs can be transplanted into living people.
” This is an important step to realize the promise of xenotransplantation, which saved thousands of lives every year in the not too distant future , ” said CEO of United Therapeutics , Martine Rothblatt , in a statement.
Experts say that tests in non-human primates and last month’s experiment on a human body pave the way for the first experimental pig kidney or heart transplants in living people in the coming years.
Raising pigs to be organ donors seems bad to some people, but could increase acceptance if concerns about animal welfare are addressed, said Karen Maschke , a research fellow at the Hastings Center , who helps develop the ethics recommendations. and policies for the first clinical trials with a grant from the National Institutes of Health.