organ transplants

Kidney transplant patient Robert Waddell, center, with his wife and children after being off immunosuppresants; photo aken last summer in Perdido Key, FL. Left to right: Christian, Bailey, Rob, Karen (wife), Robby and Casey.

Photo courtesy Rob Waddell

Rob Waddell dreaded getting a kidney transplant. He suffers from a genetic condition called polycystic kidney disease that causes the uncontrolled growth of cysts that gradually choke off kidney function. The inherited defect has haunted his family for generations, killing his great grandmother, grandmother, and numerous cousins, aunts and uncles.

But he saw how difficult it was for his mother and sister, who also suffer from this condition, to live with the side effects of the drugs they needed to take to prevent organ rejection, which can cause diabetes, high blood pressure and cancer, and even kidney failure because of their toxicity. Many of his relatives followed the same course, says Waddell: "They were all on dialysis, then a transplant and ended up usually dying from cancers caused by the medications."

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Linda Marsa
Linda Marsa is a contributing editor at Discover, a former Los Angeles Times reporter and author of Fevered: Why a Hotter Planet Will Harm Our Health and How We Can Save Ourselves (Rodale, 2013), which the New York Times called “gripping to read.” Her work has been anthologized in The Best American Science Writing, and she has written for numerous publications, including Newsweek, U.S. News & World Report, Nautilus, Men’s Journal, Playboy, Pacific Standard and Aeon.

Dr. Robert Montgomery, the director of NYU Langone's Transplant Institute, is ironically the recipient of a heart transplant.


[Ed. Note: This is the fourth episode in our Moonshot series, which explores four cutting-edge scientific developments that stand to fundamentally transform our world.]

Kira Peikoff
Kira Peikoff is a journalist whose work has appeared in The New York Times, Newsweek, Nautilus, Popular Mechanics, The New York Academy of Sciences, and other outlets. She is also the author of four suspense novels that explore controversial issues arising from scientific innovation: Living Proof, No Time to Die, Die Again Tomorrow, and Mother Knows Best. Peikoff holds a B.A. in Journalism from New York University and an M.S. in Bioethics from Columbia University. She lives in New Jersey with her husband and son.
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Pigs in a barn.

(© caspernhdk/Adobe)


The shortage of organs is a public health menace. Approximately 120,000 people in the U.S. need a lifesaving organ transplant. Of those, approximately 75,000 patients are on the active waiting list. Every day, nearly 20 individuals die from the shortage of organs in the United States.

Ethical concerns about human-animal chimera research might be dramatically overblown.

Scientists worldwide are developing new methods with potential to save countless patients in need of organs. Such approaches have tremendous potential, if only ethical and regulatory challenges could be overcome first.

One way that scientists are proposing to increase the number of transplantable organs is to produce organs from patient stem cells. Owed to their ability to grow limitlessly in the lab and form all tissue types, pluripotent stem cells from patients, in principle, could supply an infinite amount of cells that could potentially be transplanted back into patients. Unfortunately, all efforts to generate organs that can be transplanted into patients from stem cells to date have been unsuccessful.

A different encouraging approach is to generate patient organs inside livestock species, such as pigs. In the latest methods, interspecies chimeras – animals containing cells from both humans and animals – are generated by introducing human stem cells into early-stage animal embryos. Key genes essential for organ formation are disabled, allowing the introduced human stem cells to fill the empty space. In theory, this strategy will produce a human organ inside pigs or sheep.

Creating chimeras is not new in biology. Chimeras, or animals comprised of tissues from two different individuals, have already been deployed in research. Mouse chimeras are routinely used to create genetically engineered mice to study genes. The concept of generating human organs inside pigs or sheep comes from previous studies involving interspecies chimeras generated between mice and rats. Past experiments have demonstrated that it is possible to generate a rat pancreas inside a mouse.

Scientific and Ethical Obstacles

Unfortunately, chimera research has faced hurdles that have impeded progress. Of note, attempts to generate interspecies chimeras by several groups have failed. The results of these studies indicate that human cells appear unable to grow inside mouse embryos. The levels of human chimerism – the number of human cells inside the host animal embryo – appear too low to support any human organ generation.

Another obstacle is that chimera generation is ethically controversial. Some question the moral status of an animal that is comprised of human and animal cells. The most concerning question is whether human cells will contribute to the host animal's brain, potentially altering the cognition of the animal. These issues have prompted scientists to proceed very cautiously with chimera experiments. However, such concerns might be dramatically overblown. This is because the levels of human chimerism are too low to cause any significant change in animal brain function.

The ethical controversy has affected research policy in the United States. In the United States, the National Institutes of Health (NIH), the major funding body of biomedical research, blocked funding for chimera research while ethical questions were considered. Later, it was proposed that a new review process would be instated for chimera research. However, no change in policy has actually happened. The restrictive NIH policy is a major barrier to chimera research progress because laboratories around the United States cannot obtain funding for it. Lifting the restrictions on NIH funding for chimera research would dramatically accelerate chimera research.

Nonetheless, despite the past and current hurdles that chimera research has faced, new advances are changing the landscape of chimera research.

It is time to lift restrictions on chimera research so that its promise can be fully realized.

Progress on the Horizon

Scientists are developing improved strategies to increase the numbers of cells in animal embryos to the point where it might be possible to generate a human organ in an animal. For example, it has been suggested that the human stem cells researchers have been using cannot grow in animals. Scientists have made advances in generating new types of human stem cells that might have an improved ability to form chimeras.

Additionally, scientists have identified some barriers responsible for the failure to generate chimeras. For example, preventing cell death and enhancing the ability of stem cells to compete with host animal tissues also improves the numbers of human cells to the point where human organs can be generated inside an animal.

Finally, a relaxation of regulatory hurdles in other countries has created a more permissive environment for human-animal interspecies chimera research. In March, the Japanese government approved the first such experiments that could comprise a new way of generating organs from patients for transplantation.

Additionally, in spite of the somewhat negative attention that chimera generation has received, the International Society for Stem Cell Research (ISSCR) supports the new Japanese policies allowing chimera experiments. The ISSCR maintains that research involving the generation of chimeras should be permitted, as long as rigorous oversight and ethics review occur.

Chimera research has the potential to transform medicine. Of all the impediments, the NIH restrictions on funding remain the single most significant barrier. It is time to lift restrictions on chimera research so that its promise can be fully realized. One day, it might be possible to grow patient-specific organs inside of livestock animals such as pigs and sheep, saving thousands of human lives. But to change our current policy, the public, scientists, and bioethicists must first agree that this critical cause is worth fighting for.

Alejandro De Los Angeles
Alejandro De Los Angeles is a visiting researcher at Yale University. He has done research at several leading institutions, including Stanford, Yale, Columbia, and the Genome Institute of Singapore. A Connecticut native, he has published over 25 papers on stem cells and human-animal interspecies chimeras. Alejandro’s research has focused on identifying stem cells capable of forming interspecies chimeras. Recently, Alejandro discovered a new type of monkey pluripotent stem cell that might possess the capability of forming interspecies chimeras. He also showed that the same method works in human stem cells. De Los Angeles’s work has appeared in major scientific journals, including the top journal Nature. In addition to his scientific work in the laboratory, he also collaborates with bioethicists and recently co-edited a book on chimera research and ethics titled, “Chimera Research,” published by Springer Nature.

A somber photo of the Great Wall of China.

(© Andrea Leopardi/Unsplash)


Organ transplantation can dramatically improve or save lives. A heart transplant can literally give a person a new lease of life, while a kidney transplant frees the recipient from lengthy spells on dialysis.

A people's tribunal in London has recently found that in China, organs are sourced from prisoners of conscience who are killed on demand to fuel the lucrative organ transplantation market.

To protect the integrity of organ transplantation, there are strict ethical guidelines. When organs are sourced from deceased persons, the donation must be voluntary, donors must die naturally before any organs are taken, and death must not be hastened to provide organs. These ethical guidelines protect donors and provide assurance to transplant recipients that their organs have been sourced ethically.

However, not all countries follow these ethical guidelines. A people's tribunal in London has recently found that in China, organs are sourced from prisoners of conscience who are killed on demand to fuel the lucrative organ transplantation market. This conclusion, reported at the United Nations Human Rights Council on September 24, was not reached lightly.

The independent China Tribunal, made up of four human rights lawyers, one surgeon with transplant experience, an academic who specialises in China studies and a businessman with human rights interests, spent over a year looking at written materials and heard evidence from over 50 witnesses in five days of hearings. Their grim conclusion, that prisoners of conscience are murdered for their organs, confirms the findings of earlier investigations.

Questions first arose over China's transplant system when the numbers of transplants rose dramatically after 2000. Transplant capacity rapidly increased; new infrastructure was built and staff were trained. Hospital websites offered livers, hearts and kidneys available in a matter of days or weeks, for a price. Foreigners were encouraged to come to China to avoid lengthy transplant waiting lists in their home countries.

At the time, it was a mystery as to how China had a ready supply of organs, despite having no volunteer donation system. Eventually, in 2006, the Chinese government stated that organs were removed from prisoners who had been found guilty and sentenced to the death penalty. But this explanation did not ring true. Death row prisoners often have poor health, including high rates of infectious diseases, making them poor candidates for donation. By contrast, the organs offered for sale were promised to be healthy.

In 2006, the first clues about the source of the organs emerged. A woman called Annie reported that her surgeon husband had been present during organ removal from Falun Gong practitioners who were still breathing as the scalpels cut into them. A subsequent investigation by two Canadian human rights lawyers examined multiple sources of evidence, concluding that murdered Falun Gong practitioners were indeed the source of the organs.

The evidence included testimony from practitioners who had been imprisoned, tortured, and later released. During imprisonment, many practitioners reported blood and other medical tests examining the health of their organs—tests that were not performed on any other prisoners. Phone calls made to Chinese hospitals by investigators posing as patients were offered rapid access to fresh organs from Falun Gong practitioners. The organs were guaranteed to be healthy, as the practice forbids smoking tobacco and drinking alcohol.

Since 2006, evidence has continued to accumulate. China has a huge transplant industry and no plausible source of voluntary organ donations. Unlike the rest of the world, Chinese waiting times remain very short. Foreigners continue to come to China to avoid lengthy waiting lists. Prisoners of conscience, including Tibetans and Uyghurs as well as Falun Gong practitioners, are still being imprisoned and medically tested.

The Chinese government continues to deny these crimes, claiming that there is a volunteer donor system in place.

The China Tribunal heard from Uyghur witnesses who had recently been inside the notorious labour camps (also called "re-education" centers) in Xin Xiang. The witnesses reported terrible conditions, including overcrowding and torture, and were forced to have medical examinations. They saw other prisoners disappear without explanation following similar medical tests. As recently as 2018, doctors in Chinese hospitals were promising potential patients healthy Falun Gong organs in taped phone calls.

The Chinese government continues to deny these crimes, claiming that there is a volunteer donor system in place. In the Chinese system, prisoners are counted as volunteers.

China's forced organ harvesting from prisoners of conscience has international implications. A recent study found that most published Chinese transplant research is based on organs sourced from prisoners. International ethical guidance prohibits taking organs from prisoners and prohibits publication of research based on transplanted material from prisoners. The authors of that study called for retractions of the papers, some of which are in well-known scientific journals. So far Transplantation and PLOS One are among the journals that have already retracted over twenty articles in response. On questioning from the editors, the authors of the papers failed to respond or could not verify that the organs in the transplant research came from volunteers.

The international community has a moral obligation to act together to stop forced organ harvesting in China.

The China Tribunal concluded that forced organ harvesting remains China's main source of transplant organs. In their view, the commission of Crimes Against Humanity against the Uyghurs and Falun Gong has been proved beyond reasonable doubt. By their actions, the Chinese government has turned a life-saving altruistic practice into our worst nightmare. The international community has a moral obligation to act together to stop forced organ harvesting in China, and end these crimes against humanity.

Wendy Rogers
Wendy Rogers is Professor of Clinical Ethics at Macquarie University in Australia, where she teaches medical ethics and has an active research program. Over the past four years she has engaged in both academic research and activism investigating and raising awareness about forced organ harvesting from prisoners of conscience in China. Her recent BMJ Open paper found that over 90% of published papers reporting on Chinese transplant research is based on organs unethically procured from prisoners, leading to a call for retractions. She is the chair of the international advisory committee of the International Coalition to End Transplant Abuse in China. Wendy received the 2019 NHMRC ethics award and is currently leading the revision of the Australian human research ethics guidelines.

Dr. Robert Montgomery, almost one year post-transplant, at a vineyard in Casablanca, Chile, August 2019.

(Courtesy Montgomery)


Having spent my working life as a transplant surgeon, it is the ultimate irony that I have now become a heart transplant patient. I knew this was a possibility since 1987, when I was 27 years old and I received a phone call from my sister-in-law telling me that my 35-year-old brother, Rich, had just died suddenly while water skiing.

Living from one heartbeat to the next I knew I had to get it right and nail my life—and in that regard my disease was a blessing.

After his autopsy, dots were connected and it was clear that the mysterious heart disease my father had died from when I was 15 years old was genetic. I was evaluated and it was clear that I too had inherited cardiomyopathy, a progressive weakening condition of the heart muscle that often leads to dangerous rhythm disturbances and sudden death. My doctors urged me to have a newly developed device called an implantable cardioverter-defibrillator (ICD) surgically placed in my abdomen and chest to monitor and shock my heart back into normal rhythm should I have a sudden cardiac arrest.

They also told me I was the first surgeon in the world to undergo an ICD implant and that having one of these devices would not be compatible with the life of a surgeon and I should change careers to something less rigorous. With the support of a mentor and armed with what the British refer to as my "bloody-mindedness," I refused to give up this dream of becoming a transplant surgeon. I completed my surgical training and embarked on my career.

What followed were periods of stability punctuated by near-death experiences. I had a family, was productive in my work, and got on with life, knowing that this was a fragile situation that could turn on its head in a moment. In a way, it made my decisions about how to spend my time and focus my efforts more deliberate and purposeful. Living from one heartbeat to the next I knew I had to get it right and nail my life—and in that regard my disease was a blessing.

In 2017 while pursuing my passion for the outdoors in a remote part of Patagonia, I collapsed from bacterial pneumonia and sepsis. Unknowingly, I had brought in my lungs one of those super-bugs that you read about from the hospital where I worked. Several days into the trip, the bacteria entered my blood stream and brought me as close to death as a human can get.

I lay for nearly 3 weeks in a coma on a stretcher in a tiny hospital in Argentina, septic and in cardiogenic shock before stabilizing enough to be evaced to NYU Langone Hospital, where I was on staff. I awoke helpless, unable to walk, talk, or swallow food or drink. It was a long shot but I managed to recover completely from this episode; after 3 months, I returned to work and the operating room. My heart rebounded, but never back to where it had been.

Then, on the eve of my mother's funeral, I arrested while watching a Broadway show, and this time my ICD failed to revive me. There was prolonged CPR that broke my ribs and spine and a final shock that recaptured my heart. It was literally a show stopper and I awoke to a standing ovation from the New York theatre audience who were stunned by my modern recreation of the biblical story of Lazarus, or for the more hip among them, my real-life rendition of the resurrection of Jon Snow at the end of season 5 of Game of Thrones.

Against the advice of my doctors, I attended my mom's funeral and again tried to regain some sense of normalcy. We discussed a transplant at this point but, believe it or not, there is such a scarcity of organs I was not yet "sick enough" to get enough priority to receive a heart. I had more surgery to supercharge my ICD so it would be more likely to save my life the next time -- and there would be a next time, I knew.

As a transplant surgeon, I have been involved in some important innovations to expand the number of organs available for transplantation.

Months later in Matera, Italy, where I was attending a medical meeting, I developed what is referred to as ventricular tachycardia storm. I had 4 cardiac arrests over a 3-hour period. With the first one, I fell on to a stone floor and split my forehead open. When I arrived at the small hospital it seemed like Patagonia all over again. One of the first people I met was a Catholic priest who gave me the Last Rights.

I knew now was the moment and so with the help of one of my colleagues who was at the meeting with me and the compassion of the Italian doctors who supplied my friend with resuscitation medications and left my IV in place, I signed out of the hospital against medical advice and boarded a commercial flight back to New York. I was admitted to the NYU intensive care unit and received a heart transplant 3 weeks later.

Now, what I haven't said is that as a transplant surgeon, I have been involved in some important innovations to expand the number of organs available for transplantation. I came to NYU in 2016 to start a new Transplant Institute which included inaugurating a heart transplant program. We hired heart transplant surgeons, cardiologists, and put together a team that unbeknownst to me at the time, would save my life a year later.

It gets even more interesting. One of the innovations that I had been involved in from its inception in the 1990s was using organs from donors at risk for transmitting viruses like HIV and Hepatitis C (Hep C). We popularized new ways to detect these viruses in donors and ensure that the risk was minimized as much as possible so patients in need of a life-saving transplant could utilize these organs.

When the opioid crisis hit hard about four years ago, there were suddenly a lot of potential donors who were IV drug users and 25 percent of them were known to be infected with Hep C (which is spread by needles). In 2018, 49,000 people died in the U.S. from drug overdoses. There were many more donors with Hep C than potential recipients who had previously been exposed to Hep C, and so more than half of these otherwise perfectly good organs were being discarded. At the same time, a new class of drugs was being tested that could cure Hep C.

I was at Johns Hopkins at the time and our team developed a protocol for using these Hep C positive organs for Hep C negative recipients who were willing to take them, even knowing that they were likely to become infected with the virus. We would then treat them after the transplant with this new class of drugs and in all likelihood, cure them. I brought this protocol with me to NYU.

When my own time came, I accepted a Hep C heart from a donor who overdosed on heroin. I became infected with Hep C and it was then eliminated from my body with 2 months of anti-viral therapy. All along this unlikely journey, I was seemingly making decisions that would converge upon that moment in time when I would arise to catch the heart that was meant for me.

Dr. Montgomery with his wife Denyce Graves, September 2019.

(Courtesy Montgomery)

Today, I am almost exactly one year post-transplant, back to work, operating, traveling, enjoying the outdoors, and giving lectures. My heart disease is gone; gone when my heart was removed. Gone also is my ICD. I am no longer at risk for a sudden cardiac death. I traded all that for the life of a transplant patient, which has its own set of challenges, but I clearly traded up. It is cliché, I know, but I enjoy every moment of every day. It is a miracle I am still here.

Robert Montgomery
Robert A. Montgomery, MD, DPhil, FACS, is the Director of the NYU Langone Transplant Institute and a Professor of Surgery. He received his Doctor of Medicine with Honor from the University of Rochester School of Medicine. He received his Doctor of Philosophy from Balliol College, The University of Oxford, England in Molecular Immunology. Montgomery completed his general surgical training, multi-organ transplantation fellowship, and postdoctoral fellowship in Human Molecular Genetics at Johns Hopkins. For over a decade he served as the Chief of Transplant Surgery and the Director of the Comprehensive Transplant Center at Johns Hopkins. Dr. Montgomery was part of the team that developed the laparoscopic procedure for live kidney donation, a procedure that has become the standard throughout the world. He and the Hopkins team conceived the idea of the Domino Paired Donation (kidney swaps), the Hopkins protocol for desensitization of incompatible kidney transplant patients, and performed the first chain of transplants started by an altruistic donor. He led the team that performed the first 2-way domino paired donation, 3-way paired donation, 3-way domino paired donation, 4-way paired donation, 4-way domino paired donation, 5-way domino paired donation, 6-way domino paired donation, 8-way multi-institutional domino paired donation, and co-led the first 10-way open chain. He is credited in the 2010 Guinness Book of World Records with the most kidney transplants performed in 1 day. He is considered a world expert on kidney transplantation for highly sensitized and ABO incompatible patients and is referred the most complex patients from around the globe.