Researchers at the University of Alabama at Birmingham claim a groundbreaking achievement in xenotransplantation, where organs from genetically modified pigs were successfully transplanted into a brain-dead patient. This milestone represents a significant step forward in overcoming the historical challenges of xenotransplantation.
Kidney transplants from one species to another have been attempted for over a century. Still, they have largely failed due to the recipient's immune system rejecting the foreign tissue, even when using immunosuppressive drugs.
However, this recent success is attributed to a "key advance" in genetic modification. Researchers removed four pig genes and inserted six human genes, effectively preventing coagulation and making the pig kidneys more compatible with the human immune system.
This is extraordinary because the transplanted pig kidneys quickly began functioning, producing urine and clearing creatinine from the patient's body. Creatinine is a waste product that can only be removed through the kidneys via urine, making it a crucial measure of kidney function.
This breakthrough opens the door to addressing the severe shortage of human donor kidneys. In the United States, approximately 40 per cent of patients on the kidney transplant waiting list die within five years, with only 25,000 receiving transplants annually, while more than 800,000 individuals suffer from end-stage kidney disease.
However, it is important to note that this success in a brain-dead patient does not guarantee success in living patients. Some remain sceptical about the potential translation of xenotransplants to non-brain-dead individuals. Nonetheless, kidney xenotransplants offer a relatively safer option as these organs can be removed without causing death if immune rejection occurs.
Extending xenotransplantation research to living patients remains a contentious topic. Advocates argue that caution should be exercised, but the potential to save lives justifies further exploration. This pioneering work provides hope for the thousands of patients on dialysis who could benefit from kidney transplants and offers a possible solution to the shortage of human donor kidneys.