In a first successful game-changer experiment of its kind in the world, two pig kidneys genetically engineered to ensure zero rejection have been transplanted into a brain-dead man in the US.
The breakthrough was that the kidneys were not rejected during the 74 hours until the experiment lasted and even began to produce urine in the first 23 minutes.
The experiment took place on September 30 and the procedure was described in a scientific paper published in the American Journal of Transplantation on January 20. This is the first time a pig-to-human transplant procedure has been published in a peer-reviewed journal.
“This game-changing moment is a major milestone in the field of xenotransplantation, which is arguably the best solution to the organ shortage crisis,” surgeon Jayme Locke at the University of Alabama at Birmingham said in a statement.
The aim of the study is to pave the way for a clinical trial, which Locke hopes will get under way later this year.
The recipient Jim Parsons was a registered organ donor. He had longed to have his organs help others upon his death – but they were not suitable. So, he was maintained on a ventilator to keep his body functioning. His native kidneys were removed, and replaced with that of a pig.
The pig kidneys weren’t rejected during the 74-hour experiment. “Within 23 minutes, it began to make urine,” said Locke, referring to the first of the two pig kidneys transplanted. “It’s a remarkable achievement. We had a beautiful pink kidney, not one that turned black from hyperacute rejection.”
There were no changes in Parsons’ DNA – or transmission of porcine retroviruses. Importantly, the organs produced urine – liquid waste created by metabolism during the cleaning of blood.
Kidney disease kills more people each year than breast or prostate cancer. Dr Locke said: “A radical solution is needed for the organ supply crisis. The domestic pig is a promising organ source.”
Scientists have dreamed of xenotransplantation, in which organs from animals are put into humans, for decades. Pig heart valves are already widely used in humans.
The natural lifespan of a pig is 30 years, they are easily bred and have organs of similar size. Earlier this month, a US man became the first person in the world to get a pig heart. David Bennett, 57, is said to be doing well.
