Xenotransplantation: From Animal to Human

Written by Devika Chauhan

The process of transplantation has always been a meticulous, yet miraculous revolution in the field of healthcare. Just the thought of transferring someone else’s organs to someone in need, is truly outstanding. But, how functional would it be to transplant an animal organ rather than one from a human? This is where the idea of xenotransplantation sparks, carving the path towards a transformative approach in medicine. 

The term xenotransplantation is derived from the Greek root word “xenos”,  which refers to something as strange, foreign, or even alien-like. This further corresponds to the heterologous concept of tissues or whole organs extracted from different species and organisms for human usage. 

Figure 1: Center for Biologics Evaluation and Research. (2019, April 29). Xenotransplantation. U.S. Food and Drug Administration . https://www.fda.gov/vaccines-blood-biologics/xenotransplantation#:~:text=Xenotransplantation%20is%20any%20procedure%20that 

The concept of xenotransplantation has been referenced multiple times in mythologies, such as hybrid humans from the ancient Egyption god Anubis, a man who possessed a canine head. One of the earliest examples of the idea of xenotransplantation beginning to rise, originates from 1667. This was the first documented xenotransfusion by Jean-Baptiste Denis and Paul Emmerez from Paris, France, where blood from a lamb was transfused to a 15-year old boy. As medicine revolutionized through the 19th and 20th century, many practices and experiments of xenotransplantation took place, building the foundation for the extensive medical horizons we carry today. 

On January 7, 2022, at the University of Maryland Medical Center, Dr Bartley Griffith and his team operated the first successful orthotopic heart xenotransplantation. Teams of doctors and researchers transplanted a genetically modified pig heart into a 57 year old man. Through genetic alteration of the pig heart, these doctors can help prevent the patient’s immune system from attacking the transplanted organ, as well as reduce risk of rejection. According to Dr Muhammed M. Mohiuddin, professor of surgery and director of cardiac xenotransplantation program at the University of Maryland, 10 genes were modified from the original pig heart to ensure stability and increased adaptability to human response.

Research and development for xenotransplantation is growing day by day. While there still may be many ethical and social issues revolving around this innovation, animal to human transplants have come a long way. From a long established mythology to saving the lives of patients in need, centuries of practice, trial and error, and the unforgettable sacrifice of patients, have certainly paved the road for the future of xenotransplantation. 

References

Siems, MD, C., Huddleston, MD, S., & John, MD, R. (2022, March). A Brief History of Xenotransplantation. The Annals of Thoracic Surgery. https://www.annalsthoracicsurgery.org/article/S0003-4975(22)00071-6/fulltext#back-bib1

The World’s First Pig Heart to Human Xenotransplant - University of Maryland Medicine. (2022). Www.youtube.com; The University of Maryland.

Written by Devika Chauhan from MEDILOQUY