While it sounds futuristic, the first pig-to-human transplant, of a cornea, took place in 1838, John Loike, Ph.D., a biology professor, and Alan Kadish, M.D., president of the Touro College & University System, note in the article. Porcine heart valves were first used to replace failing aortic valves in humans in 1969, they add, and are still used today.

Pigs have organs similar in size to humans, are easy to genetically modify and can grow a transplantable organ in about six months. Advances in stem cell and gene editing such as CRISPR/Cas9 may soon make it possible to avoid organ rejection by seeding stem cells from a patient who needs a transplant into a pig embryo, where they would grow into the desired organ. Dr. Loike and Dr. Kadish explore the obstacles remaining to creating patient-specific transplantable organs in pigs in their article, including eliminating biological substances on the surfaces of pig cells that could lead to rejection of the organ, and removing dozens of porcine retroviruses that can infect human hosts and may trigger malignancies.

To date, the authors note, serious ethical concerns have not been raised about xenotransplantation. While some Islamic cultures forbid the use of organs from pigs, several Islamic scholars have allowed such transplants to save a patient’s life, according to the authors. Judaism permits the use of porcine products to prolong lives, while Catholic ethicists in Canada and the United States support xenotransplantation as long as it does not use aborted embryos as a stem cell source.

Another ethical challenge posed by creating human-pig hybrids, or chimeras, the authors add, would be whether this violates animal rights. “Most likely, the potential that xenograft technology can help save human life may justify the use of animals in this venture,” they write.

Despite fears about the creation of “designer babies” that arose with in vitro fertilization (introduced in 1978) and pre-implantation genetic diagnosis, available since the early 1980s, both technologies have been used to help infertile couples or those who carry inheritable diseases to have healthy babies, the authors note, and not for eugenic purposes.  “As has been the case with reproductive technology, we believe that society’s moral compass will prevent unethical use of xenotransplantation,” Dr. Loike said.

The Touro College and University System

Touro is a system of non-profit institutions of higher and professional education. Touro College was chartered in 1970 primarily to enrich the Jewish heritage, and to serve the larger American and global community. Approximately 19,200 students are currently enrolled in its various schools and divisions. Touro College has 30 campuses and locations in New York, California, Nevada, Berlin, Jerusalem and Moscow. New York Medical College; Touro University California and Touro University Nevada; Touro University Worldwide and its Touro College Los Angeles division; as well as Hebrew Theological College in Skokie, Ill. are separately accredited institutions within the Touro College and University System. For further information on Touro College, please go to: www.touro.edu/news