One of the First Successful Organ Transplants from a Genetically Modified Pig
Recently, a medical breakthrough occurred on the subject of xenotransplantation. David Bennett, a 57-year-old American senior citizen from Maryland, was a former terminally-ill patient with an unwell heart who desperately needed a new one. However, Bennett was considered ineligible for an artificial heart transplant and a normal human-to-human heart transplant due to possessing multiple heart complications, and receiving an organ transplant from a genetically modified pig quickly became his only hope. Before the surgery, Bennett mentioned, “It was either die or do this transplant. I want to live. I know it's a shot in the dark, but it's my last choice.” Since the surgery’s success, Bennett’s doctors are currently monitoring his condition to see how he fares in the future.
Xenotransplantation, as defined by the FDA, is the “procedure that involves the transplantation, implantation or infusion into a human recipient of either (a) live cells, tissues, or organs from a nonhuman animal source, or (b) human body fluids, cells, tissues or organs that have had ex vivo contact with live nonhuman animal cells, tissues or organs.” It has been a method worth investing in, in the relatively recent decades due to the constant national shortage of organ donors in the United States. The theory behind it is that by potentially genetically modifying other organisms that share similar genes with humans, there will be a stable supply of organs for patients that need them. At the moment, animals like primates and pigs are the main contenders for similar practices since they meet the aforementioned criteria. However, past attempts of xenotransplants have been unsuccessful primarily due to the consistent cases of the cells of human recipients rejecting the different tissues that make up the animal’s organs, which is what prompted multiple instances of gene-editing attempts to minimize similar cases.
In Bennett’s case, the organ he had received came from Revivicor, United Therapeutics, a biotech company from Blacksburg, Virginia. The researchers in charge replaced several pig genes with human genes responsible for the body’s acceptance of the new tissue to minimize the chance of rejection as much as possible. Should the patient’s future condition be favorable, similar surgeries involving xenotransplants from genetically modified organisms may be a part of the near future. Dr. Bartley Griffith, the surgeon who had performed the operation, expresses his excitement, stating, “This was a breakthrough surgery and brings us one step closer to solving the organ shortage crisis. There are simply not enough donor human hearts available to meet the long list of potential recipients…We are proceeding cautiously, but we are also optimistic that this first-in-the-world surgery will provide an important new option for patients in the future”. Muhammad M. Mohiuddin, one of the world’s leading figures in researching xenotransplants, also mentions that Bennett’s case was possible due to “the culmination of years of highly complicated research” and expresses his hope that the procedure provided “valuable information to help the medical community improve this potentially life-saving method in future patients.”
The only other major medical concern, besides cell rejection and the ethics regarding animal rights, is the potential spread of viruses or diseases through xenotransplantation. As the practice comes with the contact of multiple, separate organisms, the potential of human recipients receiving infection with virulent agents is a possibility, especially by the infection of retroviruses which can be deadly in a large population. Not only that, but it is also possible that these potential infections could not be easily identified with current medical technology, which poses another threat to the health of the general public. However, since xenotransplantation is still a relatively new concept, these many unanswered questions and concerns can only be answered with further research, rather than constant speculation.
Overall, Bennett’s case was nothing short of a medical marvel that resulted from the years of the greatest minds working together to achieve a feat once considered solely possible in science-fiction. While the results of his surgery are not perfectly free from uncertainty, they have been very favorable so far, and continue to show promise. Bennett’s surgery is perhaps the start of something that may be crucial in saving many lives in the future.