In a medical first, a man received a heart transplant from a pig. What does Catholic bioethics have to say?
A breakthrough in transplant surgery may soon offer life-saving options to thousands of patients languishing on U.S. organ-donor waiting lists even as it raises new questions for Catholic bioethicists. In a medical first on Jan. 7, doctors in Maryland transplanted a genetically modified heart from a pig into a human recipient.
If this experimental xenotransplantation (the transplanting of tissue or organs from nonhuman animals) proves successful, it offers the possibility of vastly augmenting the donor supply with organs harvested from genetically edited pigs or other animals. That could save thousands of lives each year. According to the U.S. Health Resources and Services Administration, more than 106,000 people are currently on waiting lists for organ donations, and 17 people die each day waiting for an organ from a human donor.
If this animal-to-human transplant proves successful, it offers the possibility of vastly augmenting the donor supply with organs harvested from genetically edited pigs or other animals.
The surgery itself, according to Catholic ethicists contacted by America, appears in compliance with standard medical ethics on informed consent and the protection of the dignity of the subject of the procedure. The patient, David Bennett, a 57-year-old Maryland handyman, knew there was no guarantee the surgery would work, but he was near death and his medical history and condition had rendered him ineligible for a human heart transplant.
“It seems to me [the medical team was] very careful in addressing the major [ethical] concerns from a medical point of view,” said Andrea Vicini, S.J., a physician and theologian at Boston College. “They relied on a new drug to contain the major medical issue when you transplant interspecies, between a pig and the human…the rejection of the transplantation.”
And the Maryland team appears to have properly addressed other ethical issues, “informing the patient and not making false promises about…the expected outcome.” He added that even experimental treatment has to offer the strong possibility of success. In this case, the genetic editing of the donor pig created the likelihood of a better outcome than previous xenotransplantation attempts because it reduced the threat of recipient rejection of the donor organ.
The surgery itself appears in compliance with standard medical ethics on informed consent and the protection of the dignity of the subject of the procedure.
(A Washington Post article published days after the surgery raised a whole new array of ethical issues related to patient selection when it revealed that Mr. Bennett had once been imprisoned because of a knife assault that left another man paralyzed.)
But the new procedure does raise questions about human identity, care for creation, social equity and communal risk even as it seems sufficiently aligned—for now—with church teaching on transplantation and xenotransplantation that date back to an address by Pope Pius in 1956.
Xenotransplantation’s identity problem
M. Therese Lysaught is a bioethicist at Loyola University Chicago and a member of the Pontifical Academy for Life. She said that Pope Pius, then speaking to a gathering of Italian doctors who specialized in cornea transplants, deemed xenotransplantation “completely morally legitimate” as long as three criteria were satisfied: the medical intervention had a likelihood of success, it would not pose any inordinate risks to the patient—“two very standard criteria for medical ethics”—and “it wouldn’t potentially affect the recipient’s identity.”
The new procedure raises questions about human identity, care for creation, social equity and communal risk even as it seems sufficiently aligned—for now—with church teaching on transplantation and xenotransplantation.
At this genesis of church teaching on xenotransplantation, the abstract and practical risk to human identity from such procedures was already at issue. “There were concerns about transplanting either gonadal tissue that could affect offspring or brain tissue that could affect how we think, our psychology and our personal identity,” Ms. Lysaught said. That framework has guided the church’s thinking since. Pope Pius’ teaching was affirmed and extended by Pope John Paul II in an address to the 18th International Congress of the Transplantation Society in 2000.
Any sort of xenotransplantation may be disquieting to some, but specific procedures, like the use of pig heart valves on human patients, have become commonplace in U.S. medicine. In assessing this latest breakthrough, “we have to be very cautious of what we might call the ‘yuck’ factor,” said Anthony Egan, S.J., an ethicist at the Jesuit Institute South Africa and at the University of the Witwatersrand, in Johannesburg, speaking from a teaching assignment in Kenya. The procedure “comes across as sort of creepy…like something out of a science-fiction horror story.”
That visceral reaction, Father Egan said, is perhaps not unlike the initial response to groundbreaking surgery that occurred in his native South Africa, when Christiaan Barnard performed the first human-to-human heart transplant in 1967. Now, decades later, “we’ve moved from a place where the idea of a heart transplant was gruesome—‘paging Dr. Frankenstein’—to a situation where heart transplants are normal.” He expects that a similar process of acceptance will occur if xenotransplants of major organs become more frequent.
Humankind will eventually overcome a fear of “genetic contamination” and perhaps even come to understand how relatively small the difference is in genetic terms between pig and human tissue, Father Egan said. He remains confident that the genetic manipulation described by Maryland doctors, at least for now, presents no contemporary ethical obstacle. “We’re not creating a chimera,” an embryonic combination of human and animal, but merely “tweaking” the animal donor genomes to make the transplanted organ more compatible with the human patient.
But Father Vicini pointed out that there are theological and anthropological implications related to xenotransplantation that will merit consideration. “Are we changing the identity of the person, if we introduce an organ that is not of the person?” he asked. (Mr. Bennett himself, in a joking assessment of the proposed surgery, wondered, “Will I oink like a pig?”)
In assessing this latest breakthrough, “we have to be very cautious of what we might call the ‘yuck’ factor.” The procedure “comes across as sort of creepy…like something out of a science-fiction horror story.”
“There are some organs or some body parts that [hold] a greater emotional or anthropological significance,” said Father Vicini. “The heart is [that] for many civilizations.” Hearts are perceived in many cultures as “the center of the person, the core of the person.”
Dominion over or care for creation?
If the impact on human identity has been a central preoccupation of church teaching regarding xenotransplantation, the fate of the animals involved in experimental advances has also been a concern. Major components of church wisdom on human organ transplants and xenotransplantation were summarized in an analysis from the Pontifical Academy for Life in 2001, “Prospects for Xenotransplantation Scientific Aspects and Ethical Considerations.”
Despite its confidence that man, “created ‘in the image and likeness of God’,” enjoys “a unique and higher dignity” than do other animals, in that document the academy warned that “humans must also answer to the Creator for the manner in which they treat animals.” It argued that “the sacrifice of animals can be justified only if required to achieve an important benefit for man.”
The academy outlined a number of ethical requirements in using animals for xenotransplantation: unnecessary animal suffering must be prevented; “real necessity and reasonableness must be respected”; and “genetic modifications that could significantly alter the biodiversity and the balance of the species in the animal world must be avoided.”
Chistopher Kaczor, a professor of philosophy and bioethicist at Loyola Marymount University in Los Angeles, was satisfied that the church’s concerns were addressed in Mr. Bennett’s surgery. “I don’t find this case particularly problematic,” he said, pointing out that the church’s view “is that transplantation in general is fine to do and that transplantation using animal parts is morally permissible.”
“It's perfectly fine to make use of animals to promote human flourishing,” he said. “We do this all the time,” using animals as sources of food and clothing. “The only difference for this case is that you have a genetically modified heart.”
But Father Egan wondered if the procedure, while satisfying medical ethics, may raise issues of “ecological ethics.”
“Do we simply treat, once again, nonhuman animals as our material that we can use for ourselves? It’s sort of the wrong reading of Genesis again, mastery over all creatures.”
“It's perfectly fine to make use of animals to promote human flourishing,” he said. “We do this all the time,” using animals as sources of food and clothing.
A new unease among scientists and the general public with research that relies on primate studies is one indication of a growing awareness of the sacredness of nonhuman life. Ms. Lysaught suggested that, at a minimum, humankind may wish to consider other promising avenues of medical research to treat human ailments that do not rely on lethal sourcing from animals.
She asked: “Is this the right way to proceed? To try to develop this [xenotransplantation] technology instead of trying to find alternative technologies like developing stem cell research and trying to grow organs or stimulate the human body to regenerate organs?” This question led two U.S. House members from California to introduce the Humane and Existing Alternatives in Research and Testing Sciences Act of 2021. The bill seeks to ensure that “non-animal methods are prioritized, where applicable and feasible,” in proposals for research to be conducted or supported by the National Institutes of Health.
Though he has not specifically spoken on the ethical issues surrounding the use of animals in xenotransplantation, Pope Francis has clearly raised questions about the “throwaway” approach of humankind to the gift of creation. His encyclical “Laudato Si’” attends to nonhuman beings of creation with an elevated sensitivity to their sacredness and dignity.
“Certainly in light of ‘Laudato Si’,’ we are moving in a direction, thankfully, where we are starting to appreciate the interconnectedness between ourselves and creation more broadly,” said Ms. Lysaught. The encyclical encouraged a holistic understanding of the place of humankind in creation “and our responsibility not to simply instrumentalize nature and use it solely for human good.”
That new attention to care of creation does not necessarily lead to extreme positions, she added—there is little risk of the church demanding vegetarianism—but it does ask Catholics to more deeply consider the question of animal welfare. Ms. Lysaught wonders what happens, for example, should Mr. Bennett’s treatment prove a moderate or long-term success, abruptly creating a market for thousands of genetically altered pigs.
“We already know what factory farming looks like for meat production,” she said. “It’s horrific, and it’s a huge vector for more zoonosis, more viruses jumping from animals to humans.”
The passing of a disease from animal to humankind is a small, theoretical risk from xenotransplantation but a risk that could have a devastating impact.
How would the mass production of such genetically altered pigs proceed “in a way that’s respectful and nurturing and values their contribution as God’s creatures to the well-being of humanity?”
“That’s not a question that’s usually asked in medical ethics. But you know, fortunately, Pope Francis is pushing us in that direction.”
Zoonosis, the passing of a disease from animal to humankind, is a small, theoretical risk from xenotransplantation but a risk that could have a devastating impact should a procedure introduce a novel virus that escapes a clinical environment. “Of course, we think about that question differently in light of the Covid-19 pandemic,” Ms. Lysaught said. An individual patient, like Mr. Bennett, may decide he is willing to accept the risk, but the pandemic has taught that those decisions may no longer be reducible to individual choice.
Catholic and secular bioethics once focused on individual decisions in the clinical setting between patients and physicians, she said, but contemporary bioethicists are challenged to consider impacts in the broader society. “We don’t really have a framework to think or talk about that. But we’re seeing that it’s a reality.”
Justice must also be a component in the evaluation of breakthrough medical procedures, Father Vicini said. “The appreciation of these developments that aim at promoting healing are situated within a larger set of concerns that [aim] to promote healing for everyone, everywhere on the planet,” he said. At a time when Covid-19 has made racial inequities in medical access and outcomes clear and when millions around the world lack minimum standards of health care, the costs of experimental procedures that benefit a comparable handful of people may seem out of balance.
Catholic and secular bioethics once focused on individual decisions between patients and physicians, she said, but contemporary bioethicists are challenged to consider impacts in the broader society.
A heart transplant in the United States costs about $1.4 million, Ms. Lysaught said, and about 3,500 are conducted each year. “Can you put a price on life? You don’t want to say, ‘Oh, that’s too much, so we won’t do it.’” But costs and equity are legitimate aspects of discernment related to health care. In theory, medical innovations promise cost saving and collateral benefits for all, but too often in practice, “given our neoliberal economized health care system,” those promises are not realized.
Genetically enhanced xenotransplantation, she added, at least threatens to undermine a booming global and ghoulish black market in organ trafficking, a trade condemned by John Paul II in his otherwise approving assessment of transplant surgery.
A novel procedure also entails novel risks. One example, according to Ms. Lysaught, is the possibility, albeit remote, of genetically modified organ-harvest animals somehow causing genetic pollution in the wild among them.
Other long-term ethical risks touch again on threats to human identity because of the emerging gene-editing and organ sharing capabilities.
Mr. Kaczor wonders if these innovations put humankind on a path that could lead to previously unthinkable experimentation. “You could imagine a situation where a kind of hybrid creature was developed that was half human and half whatever other species you want,” he said. “That could raise some serious ethical questions,” he added, acknowledging that such speculation seems right out of overwrought science fiction.
But that is just part of the job, according to Mr. Kaczor. “Before science fiction becomes science fact, it seems to me that people in bioethics might want to think about it.”