How Far Are We from Animal Organs Saving Lives?

Summary

Chasing Life: How Far Are We from Animal Organs Saving Lives?

In the June 24, 2025 episode of Chasing Life, hosted by Dr. Sanjay Gupta, the conversation delves deep into the realm of xenotransplantation—the transplantation of animal organs into humans. Dr. Gupta explores the latest advancements, ongoing clinical trials, and the potential future impact of this groundbreaking medical field.

---

Introduction to Xenotransplantation

Dr. Sanjay Gupta opens the episode by introducing the concept of xenotransplantation, emphasizing its transformative potential in addressing the global organ shortage crisis. Drawing from his extensive work on a documentary, Dr. Gupta highlights the interdisciplinary efforts that converge to make xenotransplantation a viable medical solution.

"Xenotransplantation... has become very real quickly," (01:03) he states, setting the stage for an in-depth exploration of this medical frontier.

---

Personalized Organs and "Ghost Organs"

Addressing listener questions, Dr. Gupta discusses the innovative approach of creating personalized organs through a method referred to as "ghost organs." Responding to Paul's inquiry about using an individual's cell makeup to grow organs in a lab, Dr. Gupta explains:

"Imagine you have a pig organ... the only thing left is the scaffolding of the organ. And then that scaffolding is essentially repopulated, reseeded with human cells... that essentially is a personalized organ for somebody," (02:37) he elaborates.

This method involves cleansing pig organs of their cellular material, leaving behind a structural framework that is then populated with the patient's own cells. The result is an organ tailored to the individual, significantly reducing the risk of immune rejection.

---

Current State of Pig Kidney and Heart Transplants

Dr. Gupta provides a detailed account of the current applications of xenotransplantation in human patients. To Anne from Kansas's question about the number of pig kidney transplants, their longevity, and immunosuppression protocols, Dr. Gupta outlines the following:

Kidney Transplants:

1. Rick Slayman at Massachusetts General Hospital received a pig kidney in March 2024 and lived for two additional months.
2. Lisa Pasano underwent the procedure in April 2024, also surviving for two months.
3. Tawana Looney at NYU received a transplant in November 2024 and is still alive; however, her pig kidney was removed after 130 days due to an unrelated infection.
4. Tim Andrews, the fourth recipient as of January 2025, is nearing the 130-day mark, becoming the longest-surviving patient with a pig kidney transplant.

Heart Transplants:

1. David Bennett received a pig heart in January 2022 and lived for two additional months.
2. Larry Fawcett underwent the procedure in September 2023, with ongoing survival beyond the initial months.

"All the folks I just mentioned are pioneers... they really sort of ventured out into the unknown," (07:19) Dr. Gupta remarks, acknowledging the bravery of these early patients.

---

Immunosuppression and Genetic Engineering

A critical aspect of successful xenotransplantation is the management of the immune system to prevent organ rejection. Dr. Gupta explains that:

"The immunosuppression or the anti-rejection medications are very similar to what a human-to-human transplant would take, but typically at higher doses," (07:19) he clarifies.

Moreover, the success of these transplants heavily relies on genetic modifications of the donor pigs. By engineering the pig's DNA to more closely resemble human genetics—removing certain genes and adding human transgenes—scientists enhance the compatibility of pig organs within the human body.

"The key to the success... is the engineering of the pig's DNA to make it more similar to a human's," (07:19) Dr. Gupta emphasizes.

---

Scaling Xenotransplantation to Address the Organ Shortage

In response to Alia from Kuwait's question about the timelines for xenotransplantation to become a widespread solution, Dr. Gupta provides a forward-looking perspective:

"Five years is the number that I was given over and over again," (10:24) he states, projecting that kidneys will be the first organs to scale, followed by hearts, livers, and possibly lungs.

Dr. Gupta describes the bio-secure farms where donor pigs are raised under stringent conditions to ensure organ safety and viability. These facilities are equipped with advanced filtration systems and maintain clean environments to prevent contamination.

"These are bio-secure farms... they have a high level of security," (10:24) he notes, highlighting the rigorous standards maintained at these establishments.

Despite these advancements, Dr. Gupta tempers expectations by acknowledging that xenotransplantation won't immediately solve the organ shortage crisis. With approximately 100,000 people on the waiting list in the United States alone and 17 individuals dying daily awaiting organs, a combination of solutions will be necessary.

"We’re going to need hundreds of thousands of organs potentially to try and solve the organ shortage crisis," (10:24) Dr. Gupta states, underscoring the magnitude of the challenge ahead.

He also touches upon the multidisciplinary nature of xenotransplantation, integrating technologies like CRISPR gene editing, IVF cloning, and advanced immunological studies to enhance organ compatibility and transplant success rates.

---

Conclusion and Future Outlook

Dr. Gupta concludes the episode by reflecting on the collective scientific efforts propelling xenotransplantation forward and the hope it brings to countless individuals awaiting transplants.

"It’s a fascinating field... combines so many different scientific developments... to create this field of xenotransplantation and potentially save and extend a lot of lives in the process," (10:24) he expresses.

He invites listeners to stay tuned for Part Two of the special series on xenotransplantation, promising a deeper dive into its future implications for medicine.

---

Final Thoughts

This episode of Chasing Life offers a comprehensive overview of the current state and future potential of xenotransplantation. Dr. Sanjay Gupta expertly navigates the complex interplay of science, ethics, and human resilience, providing listeners with a hopeful yet realistic perspective on the possibilities of saving lives through animal organ transplants.

For those intrigued by the convergence of technology and medicine, and the pursuit of extending human longevity and health, this episode serves as an enlightening resource.

---

Key Takeaways:

• Xenotransplantation is rapidly evolving, with recent successes in pig kidney and heart transplants.
• Personalized "ghost organs" offer a future where organ rejection is minimized through the use of patients' own cells.
• Genetic engineering of donor pigs is crucial for enhancing organ compatibility.
• While promising, xenotransplantation alone cannot resolve the global organ shortage but serves as a significant step forward.
• Ongoing clinical trials and bio-secure farming practices are paving the way for broader application within the next five years.

---

Timestamp References:

• [02:37] – Personalized Organs and Ghost Organs
• [07:19] – Current State of Transplants and Immunosuppression
• [10:24] – Scaling Xenotransplantation and Future Prospects

Transcript

[Carl Zimmer]

Chasing Life is supported by the World as yous'll Know It, a podcast about the forces shaping the future. In this season, host and science journalist Carl Zimmer speaks to some of the most respected scientists in the field of aging research about the massive changes in human longevity and what comes next. Is our lifespan set or will a breakthrough add decades to our lives? Can older brains be rewired to function like younger ones? Which so called biohacks actually work? The world as you'll know it is available now.

[Unknown Sponsor Voice]

This episode is brought to you by Temptations Cat Treats. Your cat will come running for the perfectly irresistible Temptations Creamy Puree and Temptations Lickable Spoon Cat Treats. The best time to feed Lickable Cat Treats to your cat is anytime. Feed by hand for a playful moment in a bowl for a creamy treat or as a topper to make mealtime fun. Visit temptationstreats.com to learn more.

[Sanjay Gupta]

Welcome to Paging Dr. Gupta. This is one of my favorite parts of the week because I get a chance to connect with you, to answer your questions and to hear what's on your mind. I also often get to talk about some of the big medical developments that are shaping our lives. If you caught last week's episode, for example, you know that we've been diving into something that sounds very much like science fiction, but at the same time has become very real quickly. Xenotransplantation X E N O Transplantation. That is the medical term for transplanting organs from one species into another. In this case specifically from animals into humans, even more specifically from pigs into people. Now I'm so fascinated by this. I spent two years working on a documentary and we covered everything from these special pig farms, two operating rooms, scientists, surgeons, and patients who are making this happen. I spent a lot of time with all of them. Today. I'm really excited to keep the conversation going by answering the the many questions you guys sent in. So let's get into it. Kira's back with us. What do we have? Kira? What's up first?

[Kira Daring]

Yeah, so Paul wrote in wondering something pretty fascinating about personalized organs and I'm going to read it to you. So he wrote, over the past two decades, work was happening in the area of using one's cell makeup to create an organ in the lab. Is this still an approach being considered?

[Sanjay Gupta]

Okay, Paul, this is a great question and the answer is yes. There is work that is being done in this particular space of creating basically individualized organs, one of the efforts of a company known as United Therapeutics. They work in the xenotransplant area, one of their efforts is also in creating what can best be called ghost organs. And we get a chance to see this. So imagine this, okay, so you have a pig organ, maybe a pig heart in this case, and it essentially is cleansed using these detergents of all of its biology, of all of its cells. The only thing left is the scaffolding of the organ. Okay? And then that scaffolding is essentially repopulated, reseeded with human cells, a specific human cells. Now, if you think about that, that essentially now is a personalized organ for somebody, this approach, this idea of creating ghost organs is still further off than where we are currently with xenotransplantation. But I think, to your question, this is the future, these ghost organs that are repopulated with an individual's human cells to create a personalized organ. That may be what we can expect in the future. So, for example, let's say you have cardiac disease or you have some sort of disease where you know you're going to need a transplant in the future. You could potentially create a personalized organ that would be ready to go when you need it. Before your condition gets too far along, scientists could take some of your cells simply from your blood or your skin, grow those cells, and then use them to populate the ghost organ scaffolding. Not only do you have an organ designed for you, but because they are your cells, immunosuppression, rejection, acceptance, that shouldn't be an issue. It is essentially your organ. Now, stick around. After the break. We're going to get into just how many of these pig kidneys have actually made it into humans? And the bigger question, could this really solve the organ shortage crisis?

[Unknown Sponsor Voice]

This podcast is supported by Dell introducing the new Dell AI PC. Powered by the Intel Core Ultra processor. It's not just an AI computer. It's a computer built for AI. That means it's built to help do your busy work for you. So you can fast forward through editing images, designing presentations, generating code, debugging code, running lots of apps without lag, creating live translations and captions, summarizing meeting notes, extending battery life, enhancing security, finding that file you were looking for, managing your schedule, meeting your deadlines, responding to Jim's long emails, leaving all the time in the world for more you time and for the things you actually want to do. No offense, Jim. Get a new Dell AI PC starting at $749.99 at Dell.com AI PC how those ahead? Stay ahead.

This podcast is Supported by Wonderful Pistachios. Whether you're running between meetings, dropping off the kids, or listening to a podcast, Wonderful Pistachios is the perfect healthy snack for when hunger strikes. Each 1 ounce serving of Wonderful Pistachios contains 6 grams of protein, giving you over 10% of your daily value. It's one of the highest protein nuts out there. The fact that wonderful Pistachios is a complete protein, providing you with all nine essential amino acids is why these little green wonders pack such a protein punch and that satisfying crack of opening each shell that's like snack meditation. You can also do Wonderful Pistachios. No shells for that grab and go ease. Wonderful Pistachios come in a variety of flavors and sizes, perfect for enjoying with family and friends or taking them with you on the go. When you're looking for a protein pick me up or a late night tasty treat, get snacking on wonderful pistachios. Visit wonderfulpistachios.com to learn more.

[Sanjay Gupta]

Okay, we're going to try and get to as many pages as possible. Kira, what do we have next?

[Kira Daring]

Next is Anne from Kansas and she wants to know, you know, how many pig kidney transplants have been done, whether anyone's lived long term with them and if they use different anti rejection meds than the typical transplant.

[Sanjay Gupta]

All right, first of all, how many kidney xenotransplants? Four into living patients. And the reason I say living patients is because the first couple of transplants were actually done into patients who were brain dead. These were patients who had signed up to be organ donors, but instead, in a way, they became organ recipients when they were brain dead. It was an opportunity for scientists to try and study could these pig organs actually survive in the human body. And they found that it worked. So In March of 2024, the first patient, a guy named Rick Slayman at Massachusetts General Hospital, got a transplant, a xenotransplant. And he lived for two additional months. In April 2024. A month later, Lisa Pasano got a transplant. Lived for two additional months. A few months later, November of 2024, the third patient, Tawana Looney at NYU, got a pig kidney. She is still alive, but had to have the pig kidney removed after 130 days because of an unrelated infection. And then In January of 2025 this year, Tim Andrews, the fourth patient, he still has his xenotransplant and soon is going to surpass 130 days, becoming the longest survivor in the world with a xeno transplant. Now, in addition to the four xeno kidney transplants. There have been two pig heart transplants as well, both at the University of Maryland School of medicine. January of 2022, David Bennett lived for two additional months. September of 2023, Larry Fawcett lived for an addition. Now, I just wanted to name everybody there because all the folks I just mentioned are pioneers. They volunteered, they put their hands up to do something that had never been done before and they really sort of ventured out into the unknown. Very, very brave. And as a result of their efforts, they have really advanced science. That's why I wanted to give you all their names. Now, with regard to the second part of your question, the immunosuppression or the anti rejection medications are very similar to what a human to human transplant would take, but typically at higher doses. So similar meds, but higher doses of the meds and typically a few other drugs that have been added into the regimen which have been shown to be effective so far in these early studies. The key to the success, though, make no mistake, is the engineering of the pig's DNA to make it more similar to a human's. In some cases, there were some genes that were removed. In other cases, certain transgenes were added. So human genes actually added into the pig's genome. All right, Kira, what's our last question?

[Kira Daring]

All right, Sanjay, we're wrapping up with one from Alia in Kuwait. She's asking a pretty big picture question. How far are we from this being a solution to the organ crisis?

[Sanjay Gupta]

Well, Aliyah, first of all, thanks for calling us from Kuwait. Five years. Five years is the number that I was given over and over again. Kidneys, in part are going to be the first organs to really get to scale. But it sounds like they're also going to get to hearts, livers and possibly lungs. We're about to enter clinical trials this summer with United Therapeutics and we had a chance to visit the farm where they're raising the pigs for the trials. And these are bio secure farms, look nothing like a typical farm. They have these filters and clean water and air. In some ways the food and the water and the air that the pigs are getting is even cleaner than what the humans are getting that work there. They have a high level of security. They have their operating rooms right there on campus. So they take the organs there and then send the organs directly to recipients around the country. I don't know, Aliyah, that I would necessarily say that this is going to solve the organ shortage crisis, but I think it's going to be a very important stopgap. Keep in mind some of these farms can raise thousands of pigs and there's a few of these farms around the country. But there's 100,000 people on the waiting list for organs in the United States alone, 17 people who die waiting for an organ. So we're going to need hundreds of thousands of organs potentially to try and solve the organ shortage crisis. And then there are a lot of people who don't currently qualify for a transplant, even though they probably should. They're just not sick enough. Then the question becomes, could these pig organs start to supply organs to those folks as well? It's a fascinating field. It combines so many different scientific developments. IVF cloning, crispr, gene editing, transplant, immunology, transplant surgery. All these scientific developments, some of them Nobel Prize winning developments, came together to create this field of xenotransplantation and potentially save and extend a lot of lives in the process. Thanks for being so fascinated by this like I am. And thank you for writing in your questions, sending in your questions. I always love hearing what you're curious about. And if there's something else health related you've been wondering about, don't be shy. Record a voice memo, email it to asksanjaynn.com or give us a call 470-396-0832. Leave a message and be sure to check out Part two of our Chasing Life special on xenotransplantation. I'm going to dive even deeper into what this breakthrough could mean for the future of medicine. On overall the documentary is called Animal Farm P H A R M and Part two will be on the feed Friday. Thanks for listening and I'll be back next Tuesday. Chasing Life is a production of CNN Audio. Our podcast is produced by Aaron Mathewson, Jennifer Lai, Grace Walker, Lori Gallaretta, Jesse Remedios, Sofia Sanchez, Kira Daring and Madeline Thompson. Andrea Kane is our medical writer. Our senior producer is Dan Bloom. Amanda Seeley is our showrunner, Dan Dejiula is our technical director and the executive producer of CNN Audio is Steve Lichtai with support from Jamis Andrest, John Dionora, Hailey Thomas, Alex Manasseri, Robert Mathers, Lainey Steinhardt, Nicole Pessarou and Lisa Namoro. Special thanks to Ben Tinker and Nadia Kanang of CNN Health and Wendy Brundage.

[Unknown Sponsor Voice]

The HBO original series the Gilded Age is back and so is the official companion podcast.

Are you curious about how they brought Gilded Age New York to life?

[Sanjay Gupta]

I don't understand. Which bit is not clear. None of it is clear.

[Unknown Sponsor Voice]

Want to know where the writers branched off from history?

[Sanjay Gupta]

Well, when you set your mind on a thing, no one can stop you. I take that as a compliment.

[Unknown Sponsor Voice]

Watch or listen to the official Gilded Age podcast. Wherever you find podcasts.