First Ever Genetically Modified Pig-to-Human Kidney Transplant Successfully Completed

Specialists at the University of Alabama at Birmingham have, for the first time, successfully transplanted pig kidneys into a human patient.

The xenotransplantation was performed on September 30, 2021, at UAB Hospital. Today, the first peer-reviewed research was published in the American Journal of Transplantation.

Xenotransplantation refers to tissues or organs being transplanted between different species. More than 800,000 Americans are living with kidney failure, according to experts at UAB.

UAB Xenotransplantation Team
UAB's Xenotransplant team. From left, front row: Jayme Locke, M.D., Katie Stegner, Lindsey Banks, Amy Johnson, M.D., Sara Macedon. Back row: Babak Orandi,M.D., Ph.D., Jordan Lee, M.D., Paige Porrett, M.D., Ph.D., Brett Findley, Natalie Anderson, Drew Shunk, M.D., JennyAnn Eads. The team was able to successfully perform a pig-to-human kidney transplant in September 2021. Steve Wood, The University of Alabama at Birmingham

Doctors from UAB told Newsweek that the procedure consisted of transplanting two genetically-modified pig kidneys into the abdomen of a brain-dead human patient named Jim Parsons, 57, who was involved in a dirt bike accident.

Parsons' native kidneys were removed and the kidneys of the pig from a pathogen-free facility were inserted. Pigs are viewed as promising animals in kidney transplant procedures because of their rapid ability to reproduce.

Dr. Jayme Locke was one of the surgeons who performed the groundbreaking procedure. She is the director of UAB's Division of Transplantation, as well as director of the UAB Comprehensive Transplant Institute.

Jayme Lock
Dr. Jayme Locke was one of the surgeons who performed the groundbreaking procedure. She is the director of UAB’s Division of Transplantation, as well as director of the UAB Comprehensive Transplant Institute. The University of Alabama at Birmingham

She told Newsweek that the peer-reviewed research was published today, months after the procedure was conducted because experts collected various data.

"The significance of this study is multi-factorial," she said. "A lot of progress has been made in xenotransplantation, but specific questions in the model needed to be answered."

Some of those primary questions asked whether there would be a hyper-acute or immediate reaction to the pig organ within minutes, which there was not; whether a pre-clinical test or crossmatch would identify compatibility, which it did; whether a life-threatening complication would occur during xenotransplantation, of which it did not; whether any pathogens would be discovered in the human patient's blood, which there were none; and whether the pig kidney xenotransplantation could be safely performed under necessary conditions for clinical trial, which they were.

For example, she noted, a flow crossmatch predicted a tissue match between the pig organs and Parsons—something "that had never been done before." Also, if hyper-acute reaction did occur, blood flow would have to have been restored before blood turned black and clotted from the inside out.

Locke said the transplanted kidney "turned beautiful and pink" and made urine within 23 minutes of the procedure's commencement. The kidneys remained viable until the experiment's conclusion after 77 hours.

UAB only trails the University of California-San Francisco in performed kidney transplants since data was first recorded on January 1, 1988. Between that date and December 31, 2021, UAB performed 9,055 kidney transplants and nearly 3,435 living donor transplants according to the United Network for Organ Sharing.

Parsons was a registered organ donor through Legacy of Hope, Alabama's organ procurement organization, and wanted his organs to help others after death. However, Locke said Parsons—who had a rarer AB blood type—had been brain-dead for several days by the time doctors were able to operate on his body.

Pig Kidney Transplant
Doctors perform xenotransplantation using pig kidneys in a brain-dead human patient. "A lot of progress has been made in xenotransplantation, but specific questions in the model needed to be answered," said Dr. Jayme Locke UAB's Division of Transplantation. The University of Alabama at Birmingham

Liver, heart and lung lists were exhausted and kidney transplantation was the only possible way for Parsons to be a donor. That was when she and a Legacy of Hope representative approached Parsons' family, including his ex-wife Julie O'Hara and their children, Ally, David and Cole, to gauge their interest and offer their consent.

"Jim was a never-met-a-stranger kind of guy who would talk to anyone and had no enemies—none," O'Hara told UAB's public relations department. "Jim would have wanted to save as many people as he could with his death, and if he knew he could potentially save thousands and thousands of people by doing this, he would have had no hesitation.

"Our dream is that no other person dies waiting for a kidney, and we know that Jim is very proud that his death could potentially bring so much hope to others," she said.

Jim Parsons
Jim Parsons was a registered organ donor through Legacy of Hope. Parsons with his daughter, Ally. The University of Alabama at Birmingham

Dr. Paige Porrett, a transplant surgeon immunobiologist and director of clinical and translational research at the UAB Comprehensive Transplant Institute, was involved in the procedure and study.

Porrett told Newsweek the institution has "tremendous investment" to bring an end to the organ shortage, calling it "no small mountain to climb" as it relates to design and implementation.

Paige Porrett
Dr. Paige Porrett, a transplant surgeon immunobiologist and director of clinical and translational research at the UAB Comprehensive Transplant Institute, was involved in the procedure and study. The University of Alabama at Birmingham

The next steps include a phase one clinical trial to advance such transplants into living people, as well as permission from the Food and Drug Administration to use such kidneys in living human research projects.

"This is one critical milestone, an important one, but there are many more to come to meet the need that Dr. Locke has been describing," Porrett said.

Locke said she is excited for patients and proud of being part of UAB in addressing kidney failure, which is especially prevalent in the southeast United States and in Alabama.

The health disparities are apparent, she added, noting how African Americans are disproportionately affected and have difficulty achieving living or assisted donors.

Procedures like this give her, along with others in her field, hope and a pathway to a cure. Some people never get the opportunity, she said, as kidney failure strikes and is followed by dialysis. They never make it to a waiting list, much less get transplanted—which Locke refers to as an "unmitigated crisis."

"I would describe myself as a staunch patient advocate," Locke said. "I think everything I have done in my career has been for and because of patients. This is huge. Every week I go to the clinic and evaluate patients who need a kidney transplant and candidates are more likely to die than get an organ and get transplanted. This has really been a team effort and a team accomplishment."

Updated 01/20/2022, at 3:42 p.m. ET: This story has been updated with additional information and background.