Recent transplantation of a pig’s heart into a man highlights the close relationship between species
A few days ago, amid the daily gloom of COVID-19, there was encouraging news of a pioneering surgical procedure at a New York hospital. A pig’s heart successfully transplanted into a 57-year-old man die of heart failure. ‘Xenotransplant’, as called interspecies transplant, is a reminder of the infinite possibilities of treating otherwise incurable diseases.
Transplants to replace failed organs are one of the spectacular achievements of medicine in the last century. The number of transplants has increased, the list of transplanted organs has increased and the outcomes have improved. But this field is also a victim of its own success as the number of people in need of transplant now far exceeds the availability of human organs. Humans, both living and dead, are being obtained as donors, but due to scientific, ethical and social challenges, the number of human donors is limited. The desperation for organs also creates a fertile ground to entice vulnerable people to sell their organs as we saw recently in the kidney scam in Assam.
Given the lack of the organ, it is intuitive that scientists would turn to animals. It also crosses another hurdle in human-to-human transplantation; One does not need to take consent from an animal that can be sacrificed for an organ. Of course not everyone agrees with such a narrow utilitarian view.
brief history
The use of animal organs to replace diseased humans is a very old idea. Some of the earliest blood transfusions were from animals. Early kidney and liver transplants were attempted from baboons and chimpanzees because these primates were thought to be closest to humans. In the early 1960s, a surgeon in New Orleans named Rimsma performed 13 chimpanzees for human kidney transplants. One of the recipients, a schoolteacher, went back to work and lived for 90 days. However, most of these transplants failed and were gradually abandoned.
The interest in pigs as a source of human organs has come quite recently. There are many reasons why scientists have now zoomed in on these otherwise abandoned creatures as a source. An interesting reason is that in the Western world it is more socially acceptable to raise pigs for this purpose. From a scientific point of view, pigs are genetically modified to reduce the chances of rejection by the human body. There are concerns about transmission of pig viruses through transplantation but this barrier has also been partially overcome by bioconservation and genetic manipulation. But COVID-19 will rekindle this debate.
Sounds somewhat dystopian, there are now companies breeding genetically modified pigs on specialized farms for the express purpose of transplantation. One such US-based company, Revivcor, supplied pig hearts for New York transplants.
Will this transplant promote xenotransplantation? Will this mean the end of organ shortages? Even the most optimistic scientists would agree that these are still open questions but the developed world is moving in this direction. It is only a matter of time before more xenotransplants are attempted. When this happens, the question will be whether the organ will function for a long time. And, whether it will transmit diseases hitherto unknown to humans. A dying person offered xenotransplant as the only life-saving option may not care for such questions.
The animal rights movement is not affected. PETA has condemned the pig heart transplant. It said: “Animals are not tool-sheds to raid but complex, intelligent creatures. It would be better for them and healthier for humans to leave them alone and seek a cure using modern science.” Coming from meat-eating countries, this seems somewhat contradictory. The easy public acceptance of the pig compared to other animals as a source says something about our double standards.
The New York case in India had a curious outcome. The local media suddenly remembered the bizarre story of a heart transplant performed by a surgeon named Barua in the 1990s. Some called it the world’s first attempt. Barua, who was working out of his Guwahati clinic, had transplanted the lungs and heart of a pig in 32-year-old Purno Saikia. This was clearly a premature experiment using a poor Indian as a guinea pig. This ended in disaster for the patient and Baruah, who was stripped of his medical degree.
Though somewhat shaken by COVID-19, humanity’s desire to prolong life at all costs is a given. An increasingly common cause of death and suffering is end-stage failure of vital organs (heart and liver). And as new organs successfully replace the failed ones, we’ll continue to expand the net to get them. But in our quest toward immortality, recent events show that, in good and bad ways, our lives depend not only on other humans but also on other species living on the planet; All creatures big and small.
Dr. Sanjay Nagraal is a Surgeon and Writer in Mumbai
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