For the first time ever, doctors were able to perform a successful animal-to-human transplant using a pig kidney. Surgeons at NYU Langone Health temporarily attached the kidney to two large blood vessels in a deceased patient and observed the transplant for two days. In that amount of time, the kidney was able to function exactly as a healthy human kidney would—it filtered waste and produced urine. This is a major medical breakthrough in a world where organ shortages regularly lead to death in patients who must wait for donors. In the United States, another name is added to the national organ transplant waiting list every 9 minutes, and an average of 17 people die every day from the lack of available organs for transplant.
One main challenge in xenotransplantation, the official term for animal-to-human transplantation, is that differences between the animal donors and human recipients trigger organ rejections. For instance, a sugar known as alpha-gal is found in pig cells but foreign to the human body, resulting in the main obstacle behind pig-to-human organ transplantation. In order for the surgery at NYU to work successfully, the kidney that was used came from a genetically-engineered pig, which eliminated the alpha-gal that resulted in a negative immune response in previous trials.
For scientists, pigs are desirable animals to use in organ transplants because they are already used as food, which means that utilizing their organs is less of an ethical concern over animals that are not bred for consumption. Furthermore, pigs have short gestation periods and produce in large litters. On top of that, their organs are similar to humans. In fact, pig heart valves have been successfully used in humans, and pig skin grafts have been used to treat burns for decades. A 26-year-old woman was even kept alive for several hours with a pig liver until a human liver was available for transplantation.
Revivicor, a subsidiary of United Therapeutics, is the company that engineered the pig that was used in the kidney transplant, but because of NYU’s recent breakthrough, several biotech companies are competing to develop pig organs that are suitable for human transplantation. Although the FDA approved the gene editing in the Revivicor pigs, much more research is needed to gain full approval for routine medical use.
However, raising animals specifically to be organ donors is a cause for concern among many people. The concept of biocentrism holds that all living organisms deserve equal moral consideration and have equal moral standing; if humans continue with advancements in genetic engineering and xenotransplantation, this is ethically immoral because the animal’s viewpoints are not considered. While many human lives could be saved by these revolutionary medical advancements, should we be continuing research and development in xenotransplantation at the expense of animal welfare?