Recently, scientists hooked up a genetically modified kidney of a pig to a human patient and watched as the organ successfully filtered waste from the person's body. The trial was conducted on a brain-dead patient who was a registered organ donor and whose family granted authorization for the procedure to be done. During the 54-hour trial, the kidney remained outside the patient's body where the surgeons could observe the organ and take tissue samples. Although the kidney was not implanted inside the body, the procedure still allowed the team to see whether the organ would be immediately rejected; problems with animal-to-human transplants generally develop where the human blood interfaces with the animal tissue, such as in the blood vessels.
Compared to primate organs, pig organs offer a number of advantages for transplantation. For example, pigs are formerly raised for food, produce large litters within a short gestation period and grow strikingly analogous organs to humans. Unfortunately, there is one major hurdle. Pig tissues carry a gene that codes for a sugar molecule called alpha-gal, which can make the human immune system go haywire and lead to organ rejection. Hence, the team used a kidney from a genetically engineered pig that lacked this sugar-producing gene. If and when pig-to-human transplants can be cleared for wider use, they would definitely help with the shortage of organs that are available to those in need. Numerous patients with kidney failure can not qualify to get on a list, in part, due to the scarcity of available kidneys. This experiment could lead to a solution for many of these people.
In the future, the gene editing tool CRISPR could also make pig organ transplants safer. Meanwhile, some labs are taking a very different approach to the transplant problem and are growing human tissues and organs inside pigs which can later be harvested for transplants. In proposition, they would be less prone to rejection because the organs would be made of human cells. However, the development of similar human-pig chimeras is still in its early days and raises a number of ethical concerns. Could this be the future of organ transplants?
Pigs could be our organ donors in the future
Comments