Two pig kidneys were successfully transferred to a patient by surgeons. This is a significant step in the long-running quest for animal organs that can save lives.
Jim Parsons, aged 57 from Huntsville in Alabama, received two kidneys after his kidneys had been removed.
Mr Parsons, who died in September last year, was brain dead and on life support after having suffered a traumatic head injury, but stayed alive long enough for scientists to assess the effects of the transplant with his family’s blessing.
The transplanted kidneys of pigs produced blood and urine, but were not rejected immediately by the body.
The organs remained viable until the study was ended, 77 hours – or more than three days – after the transplant at University of Alabama at Birmingham (UAB).
Results demonstrate how xenotransplantation – the transplantation of living cells, tissues or organs from one species to another – could address the worldwide organ shortage crisis.
Pigs’ heart anatomy and physiology is similar to that of humans so they are used as models for developing new treatments.
Earlier this month, David Bennett become the first patient in the world to get a heart transplant from a genetically-modified pig.
Meanwhile, in October, surgeons in New York successfully transplanted a pig kidney into a human, prior to the patient being taken off life support.
The New York procedure however transplanted one kidney from a pig outside of the patient’s body.
This Alabama procedure – which was conducted on September 30, prior to the New York procedure – involved removing Mr Parsons kidneys and inserting the two pig kidneys at the correct place inside his body.
This operation was performed by the University of Alabama at Birmingham Marnix E. Heersink School of Medicine
The organs were able to function for over three days in an experiment performed on Jim Parsons (pictured), who was a brain-dead patient on life support.
The first peer-reviewed research outlining Mr Parsons’ successful transplant by surgeons at UAB’s Department of Surgery has been published today in the American Journal of Transplantation.
‘This game-changing moment in the history of medicine represents a paradigm shift and a major milestone in the field of xenotransplantation, which is arguably the best solution to the organ shortage crisis,’ said Professor Jayme Locke, director of the Comprehensive Transplant Institute in UAB’s Department of Surgery and lead surgeon for the study.
“We’ve bridging critical knowledge gaps to obtain the safety data and feasibility data required for a clinical trial with living patients suffering from end-stage renal failure.
“This research provides new knowledge and helps us move closer towards a world where there is sufficient organ supply to meet the enormous demand.”
Mr. Parsons is a registered donor of organs through Legacy of Hope (Alabama’s organ procurement organization).
His wish was to see his organs be donated after his death.
UAB was allowed to place him on a ventilator by his family to help keep him alive during the study.
He had his native kidneys removed. The two genetically engineered pig kidneys from him were then transplanted.
The transplanted pig kidneys were obtained from 10 genetically altered pigs. These genes edits may have made the kidneys more suitable for transplantation into human beings.
According to The Huntsville Times, the obituary of Mr. Parsons (pictured) “storytelling and sense of humor and love for his children and mother were unmatched”
Ally Parsons, his daughter. The experiment lasted more than three days because the pig organs were active.
The pig kidneys had been removed from a donor pig housed at a pathogen-free, surgically clean facility, before being stored, transported and processed for implantation, just as human kidneys are.
Prior to surgery, Parsons underwent crossmatch compatibility tests with the donor animal in order to establish if they were good tissue matches.
Crossmatches are done for each human-to–human renal transplant. But, this test of pig-to–human tissue match was created at UAB. It marked the first possible crossmatch that has been validated between the two species.
The kidneys of the pig were placed exactly in the same locations as the human kidneys. They had identical attachments to both the renal artery and renal vein.
Mr Parsons also received standard immune-suppression therapy – in other words, treatment that lowers the activity of the body’s immune system.
When asked how such a transplant would have gone in an otherwise healthy patient compared to a brain dead patient, Professor Locke said there would have been ‘no difference’ in terms of process, but the outcome would have been different.
MailOnline reported that study endpoints (specifically kidney function) will vary.
The brain death environment makes it very difficult for kidney function assessment (e.g. It’s not difficult to determine kidney function by measuring creatinine clearance and urine output. (This is not surprising considering that kidneys from dead donor brains can produce little urine, and then take many weeks to eliminate it.
On how the UAB procedure differed to the similar procedure that took place at NYU Langone Health in New York in October, Professor Locke said the human brain dead recipient did not have her native kidneys removed, unlike Mr Parsons, which ‘confounds any interpretation of kidney function’.
MailOnline reports that the NYU-pig-to human kidney was also transplanted to her leg. It wasn’t in the traditional heterotopic spot for human-to/human transplantation.
First time that pig kidneys have been transplanted from animals that were genetically altered with 10 key gene editings, which may make them suitable for transplant to humans
“Mr Parsons” transplants were performed inside the abdomen at the same location as human-to-human transplantation.
The UAB team claims that their procedure shows the viability and potential for success in transplants.
Professor Locke stated that the human preclinical model was a method to assess the safety and feasibility for the pig-to non-human primate model without risk to any living person.
As people die each day on the waiting list, the breakthrough could end the organ shortage crisis.
According to UAB, Americans are waiting longer for their kidneys than they are any other organ.
“Our study has shown that human xenotransplantation is possible. It also identifies the areas in which new information is necessary to improve xenotransplantation results. This study will be used to establish a pre-clinical human model to further investigate the matter.
Transplanting pig organs to humans will increase organ availability and reduce the thousands of American deaths each year caused by organ shortages.
Today, over 800,000 Americans live with renal failure. Many don’t even make it onto the waiting lists because so many organs are available.
While dialysis may be able to sustain life for a while, transplantation can offer a higher quality of life and longer lives for those who are able.
UAB reports that kidney disease is the leading cause of death in America.