A pig kidney transplanted into a woman in her 50s in the United States maintained function for four months, setting the longest record for xenotransplantation. Afterward, kidney function ceased, necessitating the removal of the organ; however, the woman has regained her health through dialysis treatment.
As it has been confirmed that the interruption of function after transplanting pig organs into humans does not pose a direct threat to life, the scientific community is paying attention to xenotransplantation as a potential solution to the chronic shortage of human organs for transplantation.
According to the international journal Science, a woman in her 50s who received a pig kidney transplant at New York University Langone Health removed the kidney on the 4th, which was 130 days after the transplant last November. It has been reported that she began experiencing discomfort in urination since March, and her blood creatinine levels had also risen. Creatinine is a waste product generated in muscles, serving as an indicator of kidney function.
The pig that was transplanted into this woman was developed by United Therapeutics Corporation (UTC), a U.S. biotechnology corporation. More than 10 genes that trigger immune rejection in pig organs were modified to minimize rejection in the human body.
This woman, suffering from chronic kidney failure, had been undergoing dialysis treatment for nine years prior to her transplant. Kidney failure is a state in which kidney function significantly diminishes, making self-recovery difficult. While transplant surgery is a fundamental treatment method, there is a significant shortage of donated kidneys.
According to the Centers for Disease Control and Prevention (CDC), more than 37 million people currently suffer from chronic kidney disease in the United States, of which 100,000 are on the kidney transplant waiting list. However, due to a shortage of donated organs, the number of transplant surgeries is decreasing. In 2023, only 25,000 kidney transplant surgeries were performed.
Experts are considering xenotransplantation as an alternative in the current situation where the number of individuals waiting for organ transplants is overflowing. Professor Robert Montgomery of Langone Health, who performed the transplant surgery, noted, "The biggest advantage of xenotransplantation is that even if it fails, the patient can return to existing treatments to regain health. This case has demonstrated that possibility."
The female patient is quickly recovering her health while receiving dialysis again after the removal of the pig kidney. The medical community believes that even if pig organs function for a limited time, this could buy time until human organs can be obtained. For instance, a patient in urgent need of a liver transplant might receive a pig liver as a 'bridge therapy' to maintain life while waiting for a transplantable liver.
Research on xenotransplantation continues. The Food and Drug Administration (FDA) recently approved a clinical trial of pig kidney transplants involving six individuals for UTC. If results are positive, there are plans to expand the trial to a maximum of 50 participants.
Another biotechnology corporation, eGenesis, is preparing a new application to expand clinical trials with the FDA. The company previously transplanted genetically modified pig kidneys into the first patient last year and, in January of this year, transplanted a pig kidney into a second patient, a man in his 60s. Recently, it has commenced clinical trials involving the transplantation of pig livers in patients with liver failure. OrganOx in the United Kingdom will also participate in the clinical trials.
All of these corporations are applying various gene-editing technologies to enhance the safety and compatibility of pig organs. They are removing sugar components that stimulate the human immune system, reducing the risk of thrombosis, and blocking the operation of virus genes that may exist in pigs.
Experts predict that as understanding of immune rejection deepens and advances are made in gene editing technologies and immunosuppressants, the era of xenotransplantation will arrive.