Kidneys of a Genetically Modified Pig Have Been Implanted in a Brain Dead Man


Surgeons at the University of Alabama at Birmingham reported on Thursday that they had successfully transplanted a kidney from a genetically modified pig into the stomach of a 57-year-old brain-dead man for the first time.

The announcement was the latest in a series of outstanding achievements in the field of organ transplants. Earlier this month, surgeons at the University of Maryland transplanted a heart from a genetically modified pig to a 57-year-old patient with heart failure. That patient is still alive and under observation.

In September, surgeons at NYU Langone Health attached a kidney from a genetically modified pig to a brain-dead individual held on a ventilator. Despite being outside the body, the kidney was functioning normally for 54 hours, with urine and creatinine becoming waste products.

UAB surgery reported Pig-to-human organ transplantation was described for the first time in a peer-reviewed medical journal in The American Journal of Transplantation.

According to the surgical team, the pig kidneys began functioning and urinating after about 23 minutes, and it continued for three days even though one kidney was making more urine than the other.

The patients’ own kidneys were removed and there were no signs of rejection of the pig organs.

The chief surgeon, Dr. Jayme Locke said that the procedure closely followed all steps of the normal human-to-human transplant operation, addressing critical safety questions and laying the groundwork for a small clinical trial with live patients. He said he hopes to start by the end of the year.

Many of the previous operations were unique experiments, not part of ongoing trials.

Director of UAB’s Mismatched Kidney Transplant Program, Dr. “Our goal is not to be a one-off, but to advance the field to help our patients,” Locke said. “What a wonderful day it will be when I walk into the clinic and know I have a kidney for everyone waiting for me.”

Alabama has one of the highest rates of chronic kidney disease in the nation: 2,348 cases per million residents. Usually as a result of diabetes or high blood pressure, kidney disease is most common in older adults, but it disproportionately affects people of color, women, and people with less education and low income.

In Alabama, rates of kidney disease are unusually high in adults aged 45 to 64. Kidney patients who do not receive a transplant from a compatible donor should receive dialysis treatment approximately three times a week, for a few hours each time.

Dr. “Kidney failure is resistant, severe, and effective, and we think it needs a radical solution,” said Locke. He hopes to be able to offer pig kidney transplants to his patients within five years, as long as “we reach every milestone and there are no setbacks.”

In the article, he and other authors thanked the family of the brain-dead person, James Parsons, for consenting to the research, and said they would name this type of study after Mr. Parsons, a registered organ donor from Huntsville. Injury during a motorcycle race in September.

Relatives described Mr. Parsons as a gregarious person who liked to help people whenever he could. The family immediately agreed to the research.

“She would be so glad that so many people took advantage of it,” Amy Parsons Vaughn, Mr. Parsons’ sister, said in an interview. “A lot of people need a kidney.”

More than half a million Americans have end-stage kidney disease and are dependent on dialysis. A transplant is the best treatment for kidney failure, but the acute shortage of donor organs makes this option inaccessible for the vast majority of patients.

As of last summer, more than 90,000 people were on the waiting list for kidneys. The wait can be long: Fewer than 25,000 kidney transplants are performed in the United States each year, and more than a dozen people on the waiting list die each day.

Researchers have long sought to grow organs in pigs suitable for transplant into humans, and in recent years new technologies such as cloning and genetic engineering have brought this vision closer to reality.

Xenotransplantation, the practice of implanting animal organs in humans, has been advancing and beginning incessantly for decades. However, in the past few months, surgeons in this field have reported a number of new achievements.

In September, at NYU Langone, surgeons tried a kidney from a pig that had been genetically modified so that its tissue wouldn’t elicit an aggressive human rejection response. The kidney was attached to the patient’s thigh and seemed to be working the way the kidney was supposed to, making urine and the waste product creatinine for 54 hours.

But the most dramatic procedure of this kind took place at the University of Maryland Medical Center in early January. Patient David Bennett Sr. had exhausted all other treatment options and was given a genetically modified pig heart.

Scientific director of the University of Maryland cardiac xenotransplantation program, Dr. Muhammad Mohiuddin left the heart-lung bypass machine on January 11. He’s in good shape and didn’t reject the animal’s organ, he said.

Dr. “It’s been 12 days and it’s progressing – the heart is beating like a new heart,” Mohiuddin said. “It’s like we put a BMW engine in a 1960s car.”

The heart Mr. Bennett received was from a pig whose genome had undergone 10 changes, including removing four genes to prevent rejection and prevent continued growth of the organ.

Additionally, six human genes were inserted into the donor pig’s genome to make its organs more tolerable to the human immune system.

The pigs were supplied by Revivicor, a subsidiary of United Therapeutics Corporation. In addition to UAB, Dr. Locke and two other study authors. Four of the other authors in the article are Revevicor employees.

Experts said it was a great achievement that these pig organs were not rejected.

Dr. “The biggest fear in the xenotransplant community was hyper-acute immune rejection, where when you insert the new organ the body immediately rejects it,” said Mohiuddin.

NYU Langone Transplant Institute director Dr. Robert Montgomery said he welcomes the opportunity to learn more about xenotransplantation through work done at other centers.

“Given the genetic modifications and significant differences in the transplant process from our work, I’m particularly interested in the new information we can learn about the function of the kidneys,” he said.

He and other surgeons at NYU Langone said on November 22 that he had implanted another pig kidney in a brain-dead patient.

Dr. Locke said he took care to make sure that the experimental kidney surgery at UAB closely mirrored a standard allotransplantation or human-to-human transplantation.

The pig’s organs were removed in a sterile operating room that met human hospital certification standards. A standardized compatibility test has been developed prior to any transplant to ensure that the brain-dead person does not have antibodies to the pig organ that would cause rejection.

Surgeons also removed Mr. Parsons’ kidneys to determine that his urine was indeed made by the pig’s kidney and administered only standard immunosuppressant drugs commonly used in allotransplants.

D., director of clinical translational research for UAB’s transplant institute. “This is part of a larger program to make sure we can responsibly carry this to the people who are living it,” Porrett said.

“We wanted to test-drive everything in a human so that when we present it to patients, we can look them in the eye and say we did our best to make sure we know how it’s going to work. It’s a job.”



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