Would you accept an organ transplant from a pig, cow, baboon or a chimpanzee to save your child’s life, or your own?
More than 123,000 people in the United States currently need an organ transplant, and about 21 people die each day waiting for one, according to the Department of Health and Human Service, but less than 30,000 actually receive a transplant. U.S. government information on transplantation reports that an average of 79 people receive organ transplants every day, but that 18 people die each day because of a shortage of organs. In other words, there is a severe organ shortage and many of the people on waiting lists are under age 50
.
A shortage of organs means a shortage of organs from human donors, and in the years to come, non-human organs may be used to fill the gap. Known as xenotransplantation, the idea of grafting organs from non-human animals to human patients is not new, but historically, it’s been essentially a surgical research tool.
As early as 1963, 13 patients were xenotransplanted with chimpanzee kidneys, but their survival was measured only in months. A year later, the first heart xenotransplant was attempted, also with a chimpanzee donor. Since then, fewer than ten such procedures have been carried out, and the survival has been horrible. The longest survivor of cardiac xenotransplantation was “baby Fae”; she lived 21 days after receiving a baboon heart at Loma Linda Children’s Hospital in 1984. But the purpose of the procedures was not actually to save the patients lives.
“In those days, the advice to parents was to leave the baby here to die or take it home to die,” noted surgeon Leonard Baily, 25 years after he performed the baby Fae transplant, referring to a handful of congenital heart conditions that were incurable prior to the age of pediatric heart transplantation.
Essentially, the procedures like that performed on baby Fae were carried out to give the surgeons practice, and to this end they were extremely successful. The rehearsals with non-human hearts soon allowed Baily and other pediatric heart surgeons to perform human-to human heart transplants. This has saved thousands of lives since the mid 1980s and similar histories have played out with transplants of hearts in adult patients.
It’s also been the story of transplantation of other organs, such as liver. During the 1990s, baboon-to-human liver transplants were conducted at the University of Pittsburgh and this helped advance procedure that subsequently allowed liver transplants from human to human. The surgical technique is not the obstacle anymore, nor is the medical support and organ preservation that makes the transplantation possible. Instead, the limiting factor today is the organ supply, and that’s where xenotransplantation may have a new role.
In contrast to full organs, transplantation of tissues from non-human animals to human patients has a long track record of clinical success. Documentation of people being treated with non-human tissue goes back as early as 1682, when a piece of dog skull was apparently transplanted to the skull of a Russian nobleman. Over the last few decades, xenotransplantation of tissues and pieces of organs has become routine in the clinic. Many people, for example, have received replacement valves from the hearts of pigs and cows. It is completely routine now, and the decision between an animal versus a mechanical valve always comes down to tradeoff between the various clinical pluses and minuses of each.
Credit to geneticliteracyproject.org
A shortage of organs means a shortage of organs from human donors, and in the years to come, non-human organs may be used to fill the gap. Known as xenotransplantation, the idea of grafting organs from non-human animals to human patients is not new, but historically, it’s been essentially a surgical research tool.
As early as 1963, 13 patients were xenotransplanted with chimpanzee kidneys, but their survival was measured only in months. A year later, the first heart xenotransplant was attempted, also with a chimpanzee donor. Since then, fewer than ten such procedures have been carried out, and the survival has been horrible. The longest survivor of cardiac xenotransplantation was “baby Fae”; she lived 21 days after receiving a baboon heart at Loma Linda Children’s Hospital in 1984. But the purpose of the procedures was not actually to save the patients lives.
“In those days, the advice to parents was to leave the baby here to die or take it home to die,” noted surgeon Leonard Baily, 25 years after he performed the baby Fae transplant, referring to a handful of congenital heart conditions that were incurable prior to the age of pediatric heart transplantation.
Essentially, the procedures like that performed on baby Fae were carried out to give the surgeons practice, and to this end they were extremely successful. The rehearsals with non-human hearts soon allowed Baily and other pediatric heart surgeons to perform human-to human heart transplants. This has saved thousands of lives since the mid 1980s and similar histories have played out with transplants of hearts in adult patients.
It’s also been the story of transplantation of other organs, such as liver. During the 1990s, baboon-to-human liver transplants were conducted at the University of Pittsburgh and this helped advance procedure that subsequently allowed liver transplants from human to human. The surgical technique is not the obstacle anymore, nor is the medical support and organ preservation that makes the transplantation possible. Instead, the limiting factor today is the organ supply, and that’s where xenotransplantation may have a new role.
In contrast to full organs, transplantation of tissues from non-human animals to human patients has a long track record of clinical success. Documentation of people being treated with non-human tissue goes back as early as 1682, when a piece of dog skull was apparently transplanted to the skull of a Russian nobleman. Over the last few decades, xenotransplantation of tissues and pieces of organs has become routine in the clinic. Many people, for example, have received replacement valves from the hearts of pigs and cows. It is completely routine now, and the decision between an animal versus a mechanical valve always comes down to tradeoff between the various clinical pluses and minuses of each.
Credit to geneticliteracyproject.org
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