Pig Hearts for Humans
Robin Steedman-Braun
Science and Environment Editor
(Getty Images/Futurism)
The new year started off with a futuristic and unimaginable medical experiment in Baltimore, Maryland, with the first-ever person receiving a transplanted heart from a genetically modified pig.
Xenotransplantation, the transplantation of animal organs into humans, has been a widespread dream in the medical world for decades now. Xenotransplantation has been made possible with the recent advancements of CRIPR-Cas 9, a genome editing technology, which facilitates creating animal organs that are less likely to be attacked by the human immune system and lead to organ transplantation rejection.
The 7-hour surgery was performed on 57-year-old David Bennett, a patient with a long-time heart condition who didn’t qualify for a human heart transplant or other conventional treatments. This procedure was Bennett’s last resort. Since the surgery in early January, the new heart is already functional, however, Bennett is still being kept alive by a heart-lung bypass machine. In addition to the pig heart, new experimental immuno-suppressant drugs and a heart machine were used to reduce the risk of rejection as much as possible.
The pig heart was provided by Revivicor, a regenerative medicine company based in Virginia. The pig heart used in the surgery was genetically modified to remove certain genes that provoke the human immune system. Infections such as porcine retrovirus, a pig virus that can be transmitted to humans, are important risks in such a surgery. The pig was also given six human genes to help it adapt to the human body. Pigs are chosen as donor animals as their organs are of similar size to humans’, and they are easy to breed and raise in captivity.
If the surgery proves to be successful, which it has so far, ethicists will need to weigh in on the future of xenotransplantation procedures, because they are, as of right now, experimental and high-risk. When it comes to pig heart transplants, three main ethical issues arise: The first involves the medical implications of such a procedure. The risk of rejection is already high in human organ transplants, and even higher with xenotransplantation, without mentioning the possibility for a human patient to contract a porcine infection or disease. Animal rights are another important ethical issue. PETA (People for the Ethical Treatments of Animals) have condemned the procedure as “unethical, dangerous, and a tremendous waste of resources”, implying that it is not only wrong to genetically modify animals but also to kill them for human use, whether it be for meat consumption or organ donation. Finally, religion comes into question when considering pig organ transplants, and whether or not such a surgery would be accepted by Jewish and Muslim communities. All things considered, this procedure is a huge medical advancement in the realm of organ transplantation.