Can Animal Organs Save Human Lives and What Does That Ask of the Animals? With Dr. Josh Mezrich

In this episode of Causes or Cures, Dr. Eeks sits down with transplant surgeon and author Dr. Josh Mezrich to talk about xenotransplantation—the use of animal organs, primarily from pigs, to try to address the massive shortage of human donor organs.

More than 100,000 people in the U.S. are currently waiting for a transplant. For many, time runs out. Xenotransplantation offers a possible path forward, but it’s not a simple one.

This conversation walks through both sides.

We talk about the history—from early, controversial experiments using primates to today’s gene-edited pig organs—and what’s actually happening right now in human patients. But we also spend time on the part that often gets pushed aside: the ethical questions.

What are we asking of these animals?
How are they treated in the process?
And how do we weigh that against the possibility of saving human lives?

We discuss:

• The evolution of xenotransplantation and key scientific breakthroughs
• Real-world cases of patients receiving pig organs
• The role of CRISPR and genetically engineered pigs
• Ethical concerns around animal welfare and the use of nonhuman primates in research
• Whether focusing on animal organs shifts attention away from improving human organ donation systems
• The risks, including cross-species disease transmission

Dr. Mezrich also shares insights from his new book Every Living Creature, which explores both the promise and the discomfort of this field.

Dr. Mezrich is a transplant surgeon and Professor at the University of Wisconsin, where he holds the Mark A. Fischer Chair in Transplantation and serves as Surgical Director of the kidney transplant program. His clinical and research work focuses on liver and kidney transplantation, including how factors like the microbiome and biomarkers influence organ quality. He is also the author of How Death Becomes Life and his latest book, Every Living Creature, which explores the science and ethics of xenotransplantation. 

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Transcript

SPEAKER_01 0:00

Welcome to the Causes or Cures Podcast, your gateway to understanding health and groundbreaking medical research in a fun and easy to understand way. With Dr. Eeks as your host, join us as we sit down with the world's leading doctors and scientists to unravel the mysteries of health. From practical tips on well-being to the latest breakthroughs in medical research, we cover it all. Don't forget to subscribe. Now let's ignite our curiosity and together dive into today's episode.

SPEAKER_02 0:30

Hello, hello everybody, and welcome to this episode of Causes or Cures. I'm Dr. Eats, your host, and thanks for tuning in. So, transplants. Transplants. There are over a hundred thousand people in the US waiting for an organ transplant. And the reality is we're not going to meet that need relying on human donors alone, at least right now. So the question becomes where else do we look? Today's episode goes there. I am joined by transplant surgeon Dr. Josh Mesrich, author of Every Living Creature. And we are talking about xenotransplantation, uh using organs from animals, mainly pigs, to try to keep people alive while raising real questions about what that means for those animals. And I want to say this up front this isn't a clean or easy topic. Animals, pigs, well, since we're focusing on pigs, pigs are intelligent, social animals. No life is too small. I was certainly raised to uh think that way. My father's a veterinarian, and I've been involved in animal rescue my entire life. And at the same time, there are people sitting on transplant lists running out of time. So in this conversation, we walk through how we got here from early experiments to what's happening right now with gene-edited pig organs. And we spend time on the part that doesn't get enough attention, the ethical tension, what we're asking of animals, what we're willing to accept, and what this kind of scientific progress actually costs. So this is a really fascinating discussion. It was a really interesting read for sure. And this one stays with you a bit. All right. So let's connect to Dr. Mesrich and hear more from him. All right, everyone, we are connecting with Dr. Joshua Mesrich, and we're gonna talk about the book that he just wrote and I read and I really enjoyed. Different read for me, uh, learned a lot. But first, Dr. Mesrich, do you mind telling our listeners a little bit about yourself and what you do?

SPEAKER_00 2:52

Absolutely. And thank you so much for having me here. I'm excited to have this conversation. So I'm a transplant surgeon and I transplant uh abdominal organs, so liver, kidney, and pancreas organs. And I'm the surgical director of our kidney transplant program. And I also love to read, uh, love to write, uh, love to debate all of those types of things. And I live here in Madison, Wisconsin.

SPEAKER_02 3:22

And I saw a video of you. You studied Russian literature.

SPEAKER_00 3:27

It's true. I maybe I'm an unlikely person to have gone into surgery. I always loved to read, I loved comedy, I went to college with no real interest in medicine, and I was a Russian language and literature major, which I loved. I love Russian literature. I spent a lot of time in various parts of that country, but I never really thought my career would take me in that direction. In many ways, I feel like I stumbled into medical school. It is true that my dad went back to med school when I was in third grade. He was an engineer and went back to med school, and I did get to hear all his stories. And I also loved MASH and I wanted to be Hawkeye Pierce. So those were like maybe the two influences, but I stumbled into med school, didn't know anything about surgery. And I actually, I'll just briefly tell this story. My first day on my surgery rotation, I was pretty scared. I felt really uncomfortable in the OR. I was running around, didn't eat or drink. And at like 10 at night, they told me to go scrub into an operation, and I was so tired and I wanted to go home and go to bed so badly. But I went and it was a kidney transplant. And I'll never forget that the classical music was playing. It was in New York City where I went to school. And they opened the cooler and took out what looked like this lump of fat and they sewed it into this patient, and it turned pink, and then urine squirted out. And I my mind was blown. I couldn't believe that could happen. I wanted to understand who figured that out and really wanted to know if I could ever be a part of that world. So that's how I ended up in surgery.

SPEAKER_02 5:02

It's funny that you say you loved MASH. I do too. I quote from that all the time. I actually wrote to Alan Alda because he's he's big into health communication. Yes, yes. He I I wanted to, they're like, I want him to come on the podcast. And like, oh, you know, Aaron, we could send someone else. And I was like, well, no, I because I was just such a big fan of him.

SPEAKER_00 5:22

He has a podcast, and I've written many times to his organization, but I've never heard back. But he somehow reminds me of my dad in a lot of ways. My dad's still alive, so but um, and he doesn't drink like from a still before he goes to work. But I always loved that show, and there's something about him that I I connected with. So in we'll talk about it probably, but one of the big figures in xenotransplant, a lot of people think he was the basis for the character of Hawkeye Pierce.

SPEAKER_02 5:49

But yeah, that I read that. I was like, oh, that's cool. Because a mass reference. So your book, Every Living Creature, and it kind of takes us through the history of transplantation, xenotransplantation back to the 1950s, and you describe all these people that were involved in it, like with colorful details, you know, you kind of learn about their personalities, what they're doing outside of the OR2. And you talk about like the high hopes and then the disappointments that come when you know the organ fails. And it's just you can feel that, you know, that emotional like uh roller coaster. But I have to ask you the title, every living creature, why did you title it that?

SPEAKER_00 6:31

That's funny that that you're asking me that. I have I uh it's a an evocative title. And it wasn't how, you know, when you sell a book, you sell it under some title you come up with, and then your editorial team and your PR team end up with you picking the title. And every living creature was not my choice. But actually, funny story, George Church, who's like this genius at the Broad Institute, who's one of the people who figured out CRISPR, and he's a big character in the book. Um, he read the book and he's uh clearly a genius. And he reached out to me and said, Josh, I may not be the smartest person, which is ironic because he probably is the smartest person, but he said, I don't understand the title. So I think the way I look at the title, Every Living Creature, is that we're all kind of the same on the inside. We all have this genetic code that certainly between primates, pigs, and humans are quite similar. And it the idea of transplanting an animal organ into a human, maybe primates or chimpanzees is kind of easy to get your head around. But the idea that we could do it from a pig or a farm animal like that seems so crazy. But actually, every living creature has this genetic code inside them. And once we figured out both how to read the code, but also how to manipulate or edit the code, that's when it became possible to really consider xenotransplantation. So I kind of think of it that way: every living creature is the same on the inside. It's a little bit biblical too. Actually, there's some versions of the Bible that talk about every living creature leaving uh Noah's Ark. So I don't know, something biblical about that similar origin, but that's the story.

SPEAKER_02 8:14

Yeah. Well, I had to ask because I was like, I wonder why he titled it. I'm glad you asked.

SPEAKER_00 8:18

I'm glad you asked. I saw I told that story to someone and they said, so you're saying like a frog would be could be an organ donor? And I no, not a frog, but well, I mean, frogs do other things, right? Like the poison dart frog and some of the toxins and like well we could we could develop those characteristics too.

SPEAKER_02 8:38

So xenotransplantation, it's clear you know, you're excited about this, and like why, like what excites you about this as you were writing this book, as you were looking into the future, you're a transplant surgeon, this is what you do. Um, what excites you the most?

SPEAKER_00 8:54

It kind of blows my mind. I look at it the same way as putting a person on the moon. It's sort of this next frontier, and I get goosebumps when I think about it. I actually went into the lab during my training for what ended up being three years, and I went to Boston to one of the big Xeno labs, although my project wasn't specifically Xeno. And it totally fascinated me, blew my mind, and this idea that you could potentially get away. You know, the biggest problem we have in transplant is that we don't have enough organs. And so we have 100,000 people, something like that, that are waiting for organs right now, a little more than that. But there are millions of people that are suffering from failing organs. There's six million people with heart failure, there's six hundred thousand people on dialysis. This is just in this country. There's, you know, six hundred thousand people that have cirrhosis. And so if if we didn't have the shortage of organs, there are truly millions of people uh that could be treated by transplant, but we've been limited by the shortage of organs, and people have known that for a long time. Ever since the beginning of transplant, people have thought might it be possible to do xenotransplantation. And it the field has gone through fits and starts. But I think this idea that we actually, because of some huge discoveries, cloning, gene editing, have reached the point where it's realistic to think that we could have bespoke organs that are unlimited that could be bred, it kind of changes the way you would even think about what's possible, about what's possible with healthcare. It kind of can move transplant into the into the world of longevity, replacing body parts. I don't know, we squeeze out as many years as we can out of a a failing heart or a failing liver. The fact that you could just replace it is is sort of mind-blowing. But the other piece of it I will say, I'm really fascinated by pioneers, people who have this courage and think they can change the world. And actually, this is the second book I've written. My first book was about more of the origins of transplant. And I was able to spend time with some of these pioneers and and understand like what allows someone to think they could do something like this. And with this book, I've been able to spend time with what I call sort of more modern pioneers that are so convinced Xeno is gonna happen. And I think it's just it changes everything. It gives me goosebumps about what's possible. There are many ethical challenges to it that we can get into, but the the sheer magnitude of being able to genetically edit and clone organs when needed is mind-blowing to me. Have you ever performed a xenotransplant? Not into a human, but into a primate, yes. Uh pick to primate. We hope to be part of some trials that are ongoing now. So hopefully I will, but not yet. No. Some though, of course. Yeah.

SPEAKER_02 11:50

Okay. Well, I just had to ask.

SPEAKER_00 11:51

Yeah.

SPEAKER_02 11:53

What are you doing on your weekends? Um Right.

SPEAKER_00 11:55

None that I'm willing to admit to.

SPEAKER_02 11:57

Yeah, right.

SPEAKER_00 11:58

No, I have not done it.

SPEAKER_02 12:00

So my listeners, they love trivia. I love trivia too. And in the book, you talk about kind of how how Cyclosmorin was a game changer in the transplant industry. And you said it was brought back from the Norwegian soil by Novartis. I just loved the image of that.

SPEAKER_00 12:16

Like, isn't that amazing?

SPEAKER_02 12:17

Yeah.

SPEAKER_00 12:18

Novartis had this program where when people went on vacation, they would ask them to bring back uh soil samples because they knew that they were really looking for, they weren't interested in transplant as a field because it was like a pretty small field at that time and wasn't going to be lucrative. But they knew that things that were anti-inflammatory might have a big role as anti-cancer agents, uh, maybe autoimmunity, although that wasn't as big back then. And they knew some of them would come from products made by uh funguses, fungi, I guess, or you know, products that could be found in soil. And so they actually would do this mass testing of samples that were brought back. And it turned out that us, I believe a couple went to Norway and they brought back a sample. I actually think there was also a sample from Wisconsin that they found similar properties, but Norway gets the credit. But, anyways, it actually, some fungal product in that sample got tested and it was found in a cellular assay to be very immunosuppressive. It almost got dropped by the wayside, but just somehow someone showed the results to someone else and they were fascinated by it and started looking into it more. And ultimately they found that this product, which had like a ringed biochemical structure, so ultimately got named cyclosporin, ended up having these massively strong immunosuppressive properties. Nobody was thinking about transplant at this point. It actually was serendipitous that a couple of uh Roy Collins and David White ended up seeing a talk, the immunosuppressive properties of this thing, and thought we should try this in a transplant model. And they tried it first in animals and then humans. But it changed the field entirely. It, in my opinion, turned transplant from science fiction to reality or from experimental to reliable. And the outcomes went from 50% one-year survival to 90% one-year survival of a transplant almost overnight. And it it made transplant a real field in 1983 when it was approved.

SPEAKER_02 14:16

This is like just so our listeners know, from human to human.

SPEAKER_00 14:20

Yeah. So this is what we call allo transplant or human to human. People were doing some experimental xeno at that point, and we'll get into it, but this changed human transplant. So the first human transplant was done in 1954, successful human transplant, but that was between identical twins, two brothers, one of whom developed kidney failure. And that was a big deal. Uh Joe Murray performed the transplant in Boston and ended up winning the Nobel Prize for it in 1980, but it wasn't realistic that people were gonna have identical twins. And it was over the next decade or so that they had some success with non-identical or deceased owner transplants, but the outcomes were awful from 54 until really 83. Yeah. I mean, that's not very long ago. Like I remember the 80s, so I like remind people that, you know, no, it it's not.

SPEAKER_02 15:12

Yeah.

SPEAKER_00 15:12

Yeah.

SPEAKER_02 15:13

Depends who you ask, but no, it's not.

SPEAKER_00 15:15

Right.

SPEAKER_02 15:16

So for people who, you know, don't necessarily have like a medical background or a scientific background, you know, we're talking about the significance of cyclosporum, but why? Like what can you in plain language kind of tell people like what are the problems that you run into when you're transplanting an organ from a human to a human, and then also uh, let's say from an animal to a human?

SPEAKER_00 15:38

Yeah, absolutely. So we all have immune systems that protect us from outside threats, viruses, bacteria, but also internal threats like cancers, dying cells in our body, our immune system is involved in kind of the maintenance of our own health. And it's a critical part of our health. And we're all uh genetically different. And unless you have an identical twin, you know, we're all different. And the and our variation in what our immune system recognizes is critical in preventing a massive pandemic to come and wipe all of us out. We need to have different things we react to so that no one virus could take out the entire population of humanity. But the strength of this immune system has made transplant really difficult. So if I take an organ, a kidney, a liver, a heart, a lung, whatever, and I put it into someone that I'm not genetically identical to, our immune system will reject it and destroy it. The immune system is complex, so there are different versions of it. If we have antibodies, which can be one part of the immune system, and then we have cells, T cells and D cells. And typically when we talk about rejection, we're talking about a cellular response that happens over days to weeks to months. But there's some scenarios where the antibodies can reject things, and particularly if I have antibodies already in my body that are sensitized to something, that can reject something very quickly. That doesn't usually happen human to human. I don't normally have antibodies against another human unless I've had a sensitizing event. Sensitizing can be things like having getting pregnant and having a baby, and you can develop antibodies against that. There are going to be differences from the the other parent of the baby, or blood transfusions or previous transplants. But in general, we're talking about a cellular response. And we have a lot of drugs that can reduce that cellular response, and cyclosporin is one of them. We don't use cyclosporin too much anymore, but we use a very similar drug to that tach relemus. So that's the story with human-to-human. We now have a whole armamentarium of medications to prevent rejection and to make the the transplant last. You have to take those forever once you get a transplant, because even years after a transplant, if you stop those immunosuppressive drugs, people will then reject the organs. So that's the story with human to human. Now, animal to human is a bit more challenging, which probably doesn't surprise anyone. But this is sort of an interesting piece of evolution. For animals in on the in evolution below old world monkeys, so like many primates, um baboons, uh chimpanzees, monkeys, those are old world monkeys as opposed to like lemurs or some others that are new world monkeys. If we receive an organ from an old world monkey, it's a similar cellular rejection, which can be prevented with immunosuppressive medications, but it's certainly stronger than human to human. But if you get an animal organ from anything below on the evolutionary scale, below old world monkeys, they have this sugar on all their cells, which we call alpha gal. And humans and old world monkeys don't have that sugar, but we all have natural antibodies to that sugar. Now, why is that? It's generally thought that it probably about 28 million years ago, there was some sort of virus that came through and wiped out, you know, was a massive pandemic and wiped out all the primates at that point that didn't have this antibody. So it's selected out for primates that had this antibody to Alpha Gal. And then humans developed from these old world monkeys. And so we all have this so-called natural antibody. Interestingly, the new world monkeys had had had migrated elsewhere and probably didn't get faced with this pandemic, so they don't have this antibody. But any animal below that, so like if you take a pig organ or a dog organ or a sheep or a cow organ and you put it into a human, you'll rapidly reject it with this antibody response to this sugar. It's a massive rip-roaring rejection that happens in minutes. And we all continue to have this alpha gal antibody in our blood. And actually we make it because bacteria in our gut display this uh alpha gal sugar, and we continue to make that antibody. Interestingly, if any listeners heard about Alpha Gal syndrome or this syndrome that people are getting where they get a tick bite and they become allergic to red meat. Yeah, that's it's become like almost an epidemic in various areas, including the Northeast, because the ticks uh expose people to that sugar and it ramps up your alpha gal production. And then if you eat red meat, cow, pig, you react to the gal in the meat, and it causes, you know, what can be a really big uh anaphylactic reaction. So some of these transgenic pigs actually people would be able to eat them even if they had alpha gal syndrome because we knock out that sugar.

SPEAKER_02 20:26

So that's interesting.

SPEAKER_00 20:27

Yeah.

SPEAKER_02 20:28

So get into the the pigs you just mentioned, and this is where I think like they're knocking out this gene, right? So I guess that's like a whole new era.

SPEAKER_00 20:36

That's a whole new era. So like I like to think of xenotransplant in three eras. So the first era, which was from maybe 1963 until about 1989 or so, was what I call the primate era. So that's when most people who were thinking about xenotransplant were using primates. I mean, chimpanzees being the most successful because they're most genetically similar to humans. Um, baboons were also used, but they're genetically a bit more diverse from humans. And uh there were a number of xenotransplants performed using primates. In the 60s, there were a bunch of kidneys that were done with some success. And many of the listeners may remember baby Faye in 1984, who was a baby with um a heart defect, hypoplastic left heart, and got a baboon heart and had success for about three weeks, but then ultimately died. And that was a massive event. It was all over the news, and it was done out in Loma Linda, California. Um, Len Bailey was the surgeon, but there was massive protests against it. And in fact, Len Bailey had to wear a bulletproof vest and was protected by police, and his mail had to be open, all that. And actually, the primate era, I like to say it ended in the late eighties uh when they had a big Xeno conference, and for whatever reason, they invited Jane Goodall as like the keynote speaker, which I love Jane Goodall, but I love Jane Goodall, and she's you know, she was a genius and a oh, it's incredible what she was able to do in that era. But, anyways, the fact that they invited her to a Xeno meeting and she was their last speaker, and so they were presenting all their data on Xeno, and she gets up at the end and she said, I'm not gonna talk to you about your science, and I'm not really even gonna talk to you about the ethics of it. I'm just gonna tell you about this family I've been living with you know for the last 30 years. And they had names and they had emotions and they had love and hate and envy, and they used tools, and it was inarguable that these animals were, you know, had consciousness. It might surprise your listeners that not that long ago people like didn't really think animals had this consciousness, like that they were kind of just there to serve us. So, anyways, that that kind of ended the primate era, and then it moved into the pig era. The challenge was this sugar. They researchers learned early on that this would never work if we couldn't get rid of this sugar from pigs. And they tried all these strategies, they tried to absorb the sugar or use blocking antibodies, but it was never so they were transplanting pig organs into primates as a model for humans, and they were all getting rejected. But basically, it occurred to the researchers that we need to find a way to knock this sugar out. And they couldn't do it. They at the time could do a little bit of basic gene editing through homologous recombination, like in the 80s, people were doing that. It was very bulky and inaccurate. But without being able to clone an animal, it was not possible to knock out a gene. You could do it in mice, interestingly, but you couldn't do it in large animals because they couldn't get cells to divide in culture and and then actually clone an animal. So the cloning of Dolly the sheep in, I believe it was 96, was was this watershed moment when the world really changed in lots of ways, but people in Xeno realized, wait, this is now possible. And so I think that's kind of the start of the pig era. And in 2003, they cloned the first knockout, Alpha Gal knockout pig. And that improved outcomes in models quite a bit. But then some other big headwinds came and put Xeno on the back burner. I like to think when I think about innovation, particularly in healthcare, I think like usually the way it works, and at least how I see it working, is you get you'll have this big, massive discovery or event, and then you'll have incremental work. I call it like a quantum, there'll be a quantum event where something huge happens, like Dolly the Sheep uh gets generated. And then you have incremental work, hard work to try and move it along. And that's, I'm not belittling incremental work. It's critically important, but it's not maybe quite as exciting. And then you'll have another quantum leap and then more incremental work. And so I see the cloning of Dolly the Sheep as, you know, so like cyclosporin for for human transplant was the quantum event. I think Dolly the Sheep was the first quantum event for Xeno. The second, probably CRISPR gene editing. CRISPR, yeah. That's that's yeah. So, you know, people in the late 90s and the early 2000s thought Xeno was going to be huge, and Novartis put like a billion dollars into Xeno. And then unfortunately, three things happened. Number one, the results didn't move as fast as a pharmaceutical company would need them to move. Number two, the animal rights activists, particularly in the UK, where a lot of the work was being done, became very, very strong. One, UK has always had a much stronger animal rights activism than the United States. But on top of that, they had gone through the mad cow uh pandemic there, which had been so scary for everyone. And so between animal rights and this fear of infection, UK got very squeamish about pushing on Xeno. And in fact, one of the big Xenolabs got broken into and pictures and notebooks got leaked to the press, and it was this huge watershed moment. But number three, a vi an endogenous virus was discovered in pigs. So we all have viruses inserting into our genome, actually. And some people say about 8% of our genes were originated in a virus. And they found this virus in pigs, sadly called PERV or PIG and uh poor C and Dogenous retrovirus. So they needed a better PR than PERV. And that there were some papers written saying theoretically maybe this could activate after transplant. So between PERV animal rights and outcomes not moving quickly enough, the funding dried up for Xeno. And so that ended that first part of the pig era that I think didn't really revive until CRISPR and some of our modern pioneers came into it. And now we're in like the modern era of Xeno.

SPEAKER_02 26:40

All right. All right, so let's talk, let's get into the ethics of it. So, you know, I am an animal person, like true and true. So not like a crazy one, but like I but I want I so I've been reading, I read this essay on xenotransplants by Dr. Lisa Moses, and she's an animal-focused bioethicist and veterinarian at Harvard Med School. And she writes how the treatment of the animals, let alone the question of whether we should use them, has been overshadowed by concerns for human research subjects. And she writes that sentient non-human animals need to be part of the overall moral consideration. And then she lists out three crucial points to consider, which I'm gonna ask you for your thoughts on. The first concerns harm done to the animals by the process used to create pigs and grow organs. The second one is gaps and animal welfare oversight. And the third is that the misconception that pigs are the only animals used in this research, the research still requires hundreds of non-human primates. So I know that's a lot, but I just wanted to throw it at you all.

SPEAKER_00 27:47

Well, I just like to start by saying I am an animal lover as well, and I love I have dogs. I'm suspicious of cats because I think they're too smart and probably will take our organs. But no, I I've I love animals and I I struggle with this. I've worked both with small, you know, with mice in labs, but also with large animals, in fact, pigs, and they're actually wonderful, brilliant animals, very sweet, very trusting. And I've worked with primates as well. And um, it's very difficult. I just want to say, like, Tom Starzel, who's like the father of liver transplant and one of the most famous transplant surgeons ever, and um probably, I mean, one of the most important figures in our field, he figured out liver transplant on dogs and sacrificed many, many hundreds of dogs. And the field exists because of him. He's a he was a massive dog lover. He died a few years ago, but he always was surrounded by dogs as pets. And he said to me right before he died, he said, and he was in he was 90, he said, his biggest regret of his life is how many dogs he he killed to make this field a reality. So it's just a very powerful thing. You know, I I I think we all struggle like with this. And the truth is, like, there's so much medical research that does rely on animal work, and without it, I don't think we would have many surgical fields, heart surgery, bypass, heart valves, transplant, the whole field really exists because of experiment done on animals. Obviously, pharmaceutical development is very important too. And I think that's a challenge. And I think if there was a way to do a lot of this work without animals, that would be preferable. And I do think it's important to try and minimize the number of animals that are used and also to make sure they're treated very well. But I don't think it's possible for these medical fields to move forward without animal work. I spent a lot of time as I was writing this book talking to um Peter Singer, who's like a very, obviously very famous ethicist and wrote probably the most famous animal rights book in the 70s. He was actually part of the Oxford Vegetarians in in the 70s that were so incredibly fat fascinating. And actually he, although he didn't invent the term, he popularized the term speciesism, or people who think that humans are somehow are more important than animals, which obviously could be similar to racism, you know, speciesism. And it's interesting when when Len Bailey did the um baby fae transplant and he got so much protest, he he wrote quite a lot and spoke a lot about the topic. And he made the statement that, yes, I struggle with this, but it's, you know, he said there's a natural order of things, the lion eats the zebra. If I have to use another species to save a human, I think that's worth doing. Now, some people may disagree with that. I think in a perfect world, we would treat animals differently than we treat them. I think what I struggle with more probably is how we treat animals for food. I mean, we kill more than a billion pigs a year in the world for food and you know, similar numbers of cows and chickens and fish and all of that. And I think also those animals are treated very badly and live in these times of ages and are separated from factory farms are horrible.

SPEAKER_02 31:02

Horrific, right? Horrific.

SPEAKER_00 31:03

And there's no question about that. I think when you think about the idea of a lab for xenotransplant, you're talking about a very small number of animals that are treated extremely well, where pain is minimized and procedures are minimized. But you're right, they do, they are sacrificed when the organs are taken from them. But I guess the way I look at it is you're talking about a small number of animals that are being used very carefully, treated well and with respect, and can directly, you know, save human lives. And there are some people who would say, no, that's unacceptable. I mean, you can't ever sacrifice an animal to save a human life. And I think if you feel that way, I can respect that. But I also would remind people that really most major medical advances, whether it's from pharmaceuticals or operations or bypass machines or mechanical machines, really did depend on animal research. So I guess I would be a believer that we need to be smart and thoughtful and do experiments with the least number of animals needed. We need to treat them with respect. We need to just be really thoughtful about what it is we're doing, but that it is worth it because of the number of lives that can be saved by it. And that might not be totally convincing to everyone. I don't think we can just model stuff using computers or simulation and make the advances we want to make. I mean, Jane Goodall talked about this in her speech, and she would have said she would love a world where we don't do any animal research. That's for sure. She too.

SPEAKER_02 32:42

Me too, honestly. I will say this. I respect what you're saying, and like, and uh, you're right, animal research, it has led to you know, the next step being human research and then advances. I will say that I would personally struggle with like actually doing the animal research. I would also personally struggle with going out and hunting. Like it's just uh it's feelings and and this is a complicated issue though, because of that, because of the way the different views with you know with the relationship between animals and humans.

SPEAKER_00 33:12

But I want to I will say I I struggle with it too.

SPEAKER_02 33:14

Like oh, I can tell. I yeah.

SPEAKER_00 33:16

Yeah, like I think when you do large animal work, it's easier with mice. I mean, mice still matter, but like whatever. You know, it's easier to get your head around it. But when you do large animal work, whether it be with a pig or a primate, it's inarguable that these animals are sentient and interact with you and trust you. And that that is very difficult. And I think I think about as a pig, Wilbur. He's he's listening.

SPEAKER_02 33:38

He's gonna I know.

SPEAKER_00 33:39

Actually, I yeah, some pig. I read about that in my last book. Uh some anyways, when I was speaking to Peter Singer about it, because it was funny, I had read of a Vox article that said Peter Singer came out in favor of xenotransplant, and I was like, that can't be right. So I reached out to him and he responded, and he said, I wouldn't say I'm in favor of xenotransplant. He's not. That's not the words he would use. But what he would say is, if you can promise me that the animals are treated with respect, that you're minimizing pain, that they're getting, you know, free range, they're they're living an okay life, and you're sacrificing the you know, the most minimal amount, and you're really saving human lives. He said, that's not where I would spend my time fighting. Like what we really need to be fighting is the food industry and the sheer number of animals that we're treating in this way. And so I would never, I don't want to speak for him and I would not, he's not in favor of xenotransplant, but I think he's a utilitarian person, is in favor of still being able to mute move science and healthcare forward. But I agree he would also say we should be taking better care of ourselves and not relying on animals to salvage us and this kind of thing. But it's a very difficult topic. I I think if we stopped all animal research today, we would people would be surprised with the loss of scientific advances. Like we can't just model it all, but I think we could be really thoughtful about the work we do.

SPEAKER_02 35:02

Okay. So in your book and in the video I watched of you, you talked about how timing is everything. And obviously, you showed how there was like this enthusiasm and then it stopped for whatever reason. So I'm curious, you seem very optimistic about it right now, but we're in an era where federal funding is shifting away from animal research in an attempt to reduce reliance on animal testing. There's increased focus on human-relevant models, the organoids, the tissue chips, and policy changes from the FDA and the NIH to reduce animal experiments, aiming to make them the exception rather than the role. So, given all that, do you really think the timing is right? Like Yeah.

SPEAKER_00 35:42

It's tough, tough. I feel like the whole it's a tough time for the whole world. I agree. Like it's interesting. So, you know, there are something like six or seven, I want to say seven primate centers, national funded primate centers, and some of them are considering shutting down or because of these national uh endeavors to reduce animal research. And yet at the same time, we're in this weird time where we have amazing science going on and we don't know how to pay for it. We're not sure do we want to put money into research or not. We don't, we maybe want to do less animal research. And yet I remain an optimist and a xenooptimist. That's a term I coined. I want credit for that. But you're right, timing is everything. I think what we have right now is a conglomeration of incredible scientific advances, unbelievably courageous pioneers who are trying to make Xeno happen. Like people that are like mind-blowing in how fascinating they are. Public support for Xeno, I want to say that. So, like compared to what happened around Baby Faye or some of the early efforts, the publicity that came out with some of the Xenotransplants that have happened now, there's been very very little protest to that. And a bunch of money that's poured into Xeno from industry. So a couple of really big companies that are funding it. And that's what's led to trials happening right now. And the FDA has been a fair arbiter of this. Like I wouldn't say I'm not, I can't speak for the FDA, but they've been supportive of trials. So there are two trials that have been approved. So I think we're in this golden time where the science and the public support and the money have all conglomerated into one spot and these trials are happening. I don't actually expect these trials to be a massive home run. I think we're gonna have some good outcomes, but some imperfections. And I do think they're gonna need to be some more iterations of Xeno, but I think we have the right people, the right funding, the right support to get over this hump.

SPEAKER_02 37:42

Okay. So I know the wait lists are long for organ transplants. And if you're on that list waiting, if you're a family member of someone who's on that list, it's heart-wrenching, it's awful. I had a couple people on my podcast before talking about, you know, the transplant industry. And, you know, for example, one person talked about she donated one of her kidneys to a stranger, and which I found remarkable. In another one of the episodes, we talked about how transplant centers are graded. For example, they might be graded by survival outcomes, like how long a person lives with a transplanted organ. So in turn, that may create risk aversion and how some marginal organs may be turned down. So, my question to you as a transplant surgeon, in your opinion, do our current metrics in transplant medicine ever unintentionally discourage the use of higher risk human organs that could still save lives, and at least right now, maybe even longer than what you're seeing with the xenotransplants?

SPEAKER_00 38:42

Yeah, I mean, it's a great question and incredibly topical right now. I I think um we in some ways we are victims of our own success. You know, back in the 70s, people were pretty okay with the idea that transplant was really high risk and that people wanted to go for it. They either wanted to live or they wanted to push science forward. And now we can get really great outcomes with organ transplant. Like with kidney transplant, we can get a 97% one-year survival. Or, you know, every all the organs are better than 90% one-year survival. We have developed a system where, you know, transplant programs, the data is gathered and looked at nationally, and programs are watched in terms of their outcomes, and they're watched very closely, both in terms of mostly in terms of one-year survival of the patient or the graft after transplant. People do look at weightless survival and other factors, but those are the things people watch most carefully. And although they are risk adjusted, so if I take an older patient or a sicker patient, you know, the regulatory body might say, okay, you can get a little worse outcome with this patient. No one practicing thinks that the adjustments really capture how sick a patient might be. So I do agree that most programs know real time where they are in terms of their outcomes, and it can potentially affect both who they're willing to list for transplant and also what organ they're willing to accept. So let's just talk about kidney because that's the most voluminous uh transplant we do, and it's where you get the most offers. We do a lot of, we we we offer over or big geography because the thought has been to try and reduce geographic disparity. But when you're on call for kidney, you might get called with 10 offers overnight from all over the country. Some of the offers are like obvious, you know, a 20-year-old died in a motorcycle accident, perfect kidney function. Everyone is saying yes to that transplant. But a lot of the offers can be older donors who had illness themselves, you know, a 68-year-old donor had diabetes, died of a stroke, kidney function was okay, biopsy shows a little bit of disease, it's an imperfect organ, and you think, hmm, this kidney might work for a period of time, but I'm not sure how long it will work. Now I think there can be a couple of reasons why you might decide not to transplant that organ. One reason can be, oh, if I do this, the patient might do badly and my program might get in trouble. That could be one reason. I think a bigger reason is that I know what happens when a transplant doesn't go well and a patient doesn't get a good outcome and they suffer. Like that feels really terrible. So I think sometimes we make a sort of paternalistic decision that, oh, I think they can do better. I don't want to transplant this organ. And because of that, organs do get turned down. I mean, we know that we end up discarding a lot of organs that maybe could have been used. So I think the regulations can prevent some risk taking for appropriate patients, but also trying to decide how to use an imperfect organ into a sick patient is really difficult. And this is one of the reasons why I think if we ever had a scenario where we had unlimited high-quality organs, it would change everything. I mean, it would allow you to take a patient and say, we can we can make you your life so much better and you know do this in a reliable way. So I do agree that the regulations prevent some risk taking that patients would want. There are many patients suffering on dialysis or suffering with liver disease or suffering with heart failure that would be willing to take that risk. But I also think some of it is just like this fear that you might hurt someone. And that those things both work together. It's really a difficult decision to make when you get offered an organ. And you can get offered 10 organs in a night.

SPEAKER_02 42:31

Wow.

unknown 42:31

Yeah.

SPEAKER_02 42:32

I mean, but you I mean, I mean, just thinking, like, yeah, the outcomes are not going to be perfect. And I know it's obviously a complicated Charlie Foxtrot type of situation, ethical debate, but I would still think like someone would be able to get something good out of an organ, even if it's pretty beat up.

SPEAKER_00 42:48

Like, I do agree with that. So I think if you if you had enough time and you had the right patient, you could really have a good discussion. I think a lot of these organs could be used. And there's been a lot of discussion in in our community about how how should we be allocating, what's the best way to allocate sort of imperfect organs? You know, can we have a pool of patients that are appropriate for that? And I think the answer is yes. I think there's a a broad desire to reduce the number of organs that get discarded or not used with organ transplantation. You know, there have been a lot of articles written about this. The New York Times has covered this a lot, and about skipping on the list about organ discard. And I just want to be clear, like, I think some of the articles were a little misleading. Like, I think primarily the organs that either get transplanted out of sequence or discarded are organs that are, yeah, like you called beat up. I probably not the word we use in transplant, but I like it. We're not supposed to use the word marginal, by the way, but I say it, you know, marginal organs. And you're trying to figure out who's the right person for this organ. It's probably not the person that's right at the top of the list that's close to getting a different offer, but it might be someone who's farther down the list. And how can we allocate? Allocate those organs to the right people is an ongoing uh debate. And I think the regulations are one part of the problem. I do think transplant programs should have an ability to take a lot of risk for a patient that wants to take that risk without getting nailed for it. But I think as much as people fear the regulations, they just feared having a doing something having hurting a patient, right?

SPEAKER_02 44:23

Hurting a patient.

SPEAKER_00 44:24

Yeah.

SPEAKER_02 44:25

It's not not easy decisions. All right. So for our listeners, we only need one kidney to survive. So, in your opinion, should we or why haven't we seen more movement towards incentivizing living organ donations in the US?

SPEAKER_00 44:40

Yes. And this is one of my favorite topics. I've I've been our living donor kidney director for a lot of years as well, and do a lot of that operation. And um, donors are amazing. They're like the heroes of the world, they're beautiful people to me. And they get a lot out of the donation, maybe not medically, but this elation, this thing that I think for the rest of their lives they remember, you know, they've done this incredible thing. And I actually think in this world we're living in that feels so crazy, living donation is what reminds me that people want to help each other and that we're all the same on the inside. See, every living creature is the same. So but back to the type. But the you know, the challenge of living donation is that in healthcare, you know, the whole do no harm, I mean, we're doing an operation on someone that doesn't need it. And so there's always been this like hesitation to compensate donors, whether it be with money or some other way. And I actually wrote an article sometime back in The Atlantic, but other people have written this too, so I don't want to take credit for it. But wouldn't it be great if I wish we had a system where everyone had great healthcare, but we don't have that system? What if we offered every living donor, you know, Medicare or the best insurance for the rest of their life? And if you do, like the truth is these are the healthiest patients by definition. And the truth is you save so much money with a good kidney transplant into a patient with kidney failure that the healthcare system would actually save tons of money if they just gave free Medicare to all donors for the rest of their life. Uh, it would be a money saving. And I went through those calculations in the article. But again, other people have written that too, so I don't want to take total credit.

SPEAKER_03 46:16

Good idea.

SPEAKER_00 46:17

The idea of just using money of paying someone has been debated a lot. And some people are in favor of it, and some people are not. I think that the dangers are out there of, well, who are the people that are going to really take money to donate? And they're mostly going to be people that are in a situation where they need money, are they in desperate straits? I mean, when you look at transplant tourism or the places where people donate for money, uh, it tends that tends to be that their health gets worse, their life gets worse. And you might think maybe, and that tends to be in places like India, um parts of Asia. There was an incredible article in India where they have a place called the Donor Belt where tons of people, the creditors, come and tell them you got to donate an organ to pay your debt. And it was in Jam, an incredible piece. But I think if you had a regulated system where people got health care and they were really well evaluated, most ethicists could get behind a system where people were paid money. But like my my gut feeling is it would be better to do something like either health care, uh free health care or something like educational benefits or that kind of thing. I mean, transplant depends on public trust and it it has to be part, it has to be a system where something beautiful is happening, where this gift is being given. And I worry that if if you just do it with money, it's really gonna be poor people or people in desperate straits that get f in some way pushed into doing it. And of course the pair would always be centralized. It wouldn't be like a rich person paying a poor person, it would be like presumably government. But I think there's danger in that, although I'm not ethically 100% against it. I do want to say we we um we do our living donors through this paired exchange. So there's this organization called the National Kidney Registry or NKR, and they're based in New York, but they're or Connecticut maybe, but they're this big organization that facilitates swapping of organs. So if someone comes forward and says, I want to don, I just want to donate a kidney into the pool, um, we'll do it through the NKR. So that kidney can get sent on a plane to someone else who has a donor that's not compatible to them, and then their donor can give to someone else, and it can generate either a chain or a big group of pairs to maximize that donation. And interestingly, NKR has put in place some protections. So like if a donor ever needs a kidney themselves, they'll they'll end a chain on that donor. So it's right.

SPEAKER_02 48:43

They can like kind of they don't have to worry about, yeah, because that's a worry. Like, well, what if what if my one kidney that's left goes out and then I need one?

SPEAKER_00 48:49

Yeah, right. So I think donating a k an organ, we've just been talking about kidney. You can donate part of a liver to um, you know, donating blood and other blood products. It's just a beautiful thing. And it reminds me like that there's so much good in this world. And I I think it's just a beautiful thing to be a part of. And uh maybe one of the biggest joys of my career is being part of the living living donations. And I don't know, maybe at some point I'll find time to do it myself.

SPEAKER_02 49:15

But oh, you would consider it?

SPEAKER_00 49:18

I don't know.

SPEAKER_02 49:18

I mean, I did interestingly You'd probably be really picky about your surgeon since you are one.

SPEAKER_00 49:22

Right. I'd have to do the surgery on myself because I'm the best one.

unknown 49:26

I'm just kidding.

SPEAKER_00 49:26

That's a very surgical thing to say. Um it's funny. Uh our our old head of nephrology or pick uh kidney medicine wanted to donate a kidney, and he had come to me and said, at some point I'm gonna donate a kidney and I want you to do the surgery. And and I was hoping it wouldn't happen because I was kind of nervous about that. But years later, after his kids went off to college, he did it. He stepped forward and he donated a kidney, and it was this beautiful celebration in a way. And you know, he walked the walk and it has made me think about it. But like everyone, it's like, where are you gonna find the time and when's the right time to do it? But I think it's a beautiful thing, and our donors do great. I'm not gonna say it's zero risk, nothing is zero risk, but our donors do great and it's minimally invasive, and they live normal lengths of life and all of that.

SPEAKER_02 50:13

But so I interviewed a man, he was a CEO of Vital 3D Technologies for trial site news. I also wrote about it on my blog, and his company's working on bioprinting solutions, basically printing organs, and it sounded so complicated. Yes, just like the blood supply, getting the blood supply right. I mean, I was just flabbergasted by it all. What are what are your thoughts on that? Are you excited about that at all, you know, as much as xenotransplantation at all? Or are you like, no?

SPEAKER_00 50:43

No, I am I'm not gonna say as much because I'm a xeno optimist, but I think there are a number of innovations and technologies that are extremely exciting. And I think some of the quantum improvements we've had in science are gonna open the doors for a lot of these things. I think Xeno is on the is at the forefront at this moment because we actually have clinical trials that, as we speak, are happening. There are people walking around with bikinis inside them as we speak. But I think there's some other technologies that are also gonna be very exciting and potentially can work. Some are going to be cellular therapy along with gene editing. So, like for instance, for type 1 diabetes, I think the idea of being able to take stem cells and then maybe genetically manipulate them, uh, grow them, and use them to replace eyelet cells for type 1 diabetes is gonna be realistic. And I'm a believer that in the next decade we're really gonna be able to make a huge dent in type 1 diabetes. I think for other organs, maybe heart, maybe liver, maybe there'll be cellular abilities to inject cells and have them repopulate or kill an organ. That could be possible. But then I think there are these other ideas where, like, yeah, you you have a organ scaffold and then you 3D print stem cells onto that scaffold, and people are trying to do that kind of thing for lung, uh, maybe for liver. I think those technologies have potential. My gut feeling is they're a little bit behind Xeno, and but I'm not against them. I don't I think they have potential. So I don't know the exactly what technology you you're talking about here, but I think all of these things have potential and can work. I think they're gonna take some time and they're gonna take trial and error. And I I do think they're gonna take some use of animals to get them to reality and as a model, like like you would meant you know, as a model as a human recipient.

SPEAKER_02 52:34

So you're like, you can't just get rid of animal research. You're you're not seeing that.

SPEAKER_00 52:38

I think I don't think I think if you stopped all animal research now, you would stop so much development of improvement of medical technology. So you could take the idea that like, well, people shouldn't live healthier, and we know a lot about that that we didn't used to know, and try and reduce disease. And but I I do think to advance these technologies, you're gonna need to do animal research before you get into humans. And I think we could reduce, we could probably do a better job of every the perfect study should be designed as the least number of uh patients or animals needed to answer the question. So really well-designed studies that have a clear hypothesis that can be tested with a small number of animals is critical. And I think sometimes what we do is we start doing the study before we've really identified a good enough scientific method to be able to reduce that number. And I think you do a better job of that. I don't I think if you stopped it all now, we we wouldn't be able to get these types of things into the clinic.

SPEAKER_02 53:39

So Tim Andrews, I think that's he had so he had a pig kidney for 271 days, and it came from Wilma, the pig, and he talked about her, he called her his hero, and he was saying, like when he had the pig kidney, he was walking his dog cupcake, he threw out the first pitch at Fenway Park, like he did all these things, and then something went wrong after 271 days. So what happened? Why yeah.

SPEAKER_00 54:08

I think by the way, he's from he was from New Hampshire and had his transplant at Mass General, and I think throwing out the first pitch at a Red Sox game was like probably bigger to him than getting the pig. But uh that's true. No, no, he's an amazing person, and he is the longest living recipient of a genetically modified pig organ. He's actually not the longest recipient of a xenotransplant that remains a young woman in 1964 who received chimpanzee kidneys.

SPEAKER_02 54:37

That's a 19-year-old?

SPEAKER_00 54:38

Yeah, she was a teacher down in New Orleans and Keith Remsma did her transplant. Um she lived just a bit longer than Tim Andrews. Anyways, that's neither here nor there. I think the challenge we have now, we've reached a point where we can do genetically modified pig organs, kidneys or potentially or hearts, there have been some hearts done, that can work well out of the gate and that can probably work six months to a year, but they require a lot of immunosuppression because even though we've gotten rid of that sugar and some other things that I talked about earlier, and we've done some other edits. There's many edits. Actually, the one Andrews got had 69 gene edits because it cut out this virus. It cut out the PERV virus. George Church was the person who designed this pig, and then it knocked out some sugars, and then it had some immunomodulary uh modulatory genes knocked in. So it it ultimately had 69 edits. The other big company has a 10 gene edit pig. And that has reduced rejection, but it's still a stronger rejection than we see human to human. And so, although I think in a well-chosen recipient, we can get six months to a year, maybe a little longer, it requires a lot of immunosuppression. And I I don't know all the details of how Mr. Andrews lost his kidney, but I think he had some infectious issues, probably some rejection, you know, and ultimately lost the kidney. I think this iteration, I think some patients can get longer than a year, but it's gonna be hard to get most longer than that. I think next iterations are gonna be significantly better. Some of those are already in the lab now and looking even more promising. And they look really promising in the pig to primate model, where we can get many years out of those transplants as a model for humans. So I do think we're gonna need another iteration to get to a point where a pig organ is as good as a human organ. So I think for some patients who need a bridge, whether they don't have dialysis access, or maybe uh some children who have heart failure that we can't do mechanical hearts or VADs because they're too small, a pig organ could bridge them to that. I think it'll be the next iteration that might compete with a human organ. And I'm fingers crossed that we get to that iteration, despite some of the barriers that you mentioned earlier with funding and support. I think all the science is there to get there, and all of the pioneers are there, and there are patient, courageous patients that want to give it a try. So I think we can get there, but he lost his. It was a sad day when I heard that he lost his kidney. And we'll see. Yeah, he actually got a human kidney just recently. I just read it.

SPEAKER_02 57:20

Oh, oh, okay.

SPEAKER_00 57:22

Something like a month, or I don't know the exact day, they announced he got a human kidney. So he now is off dialysis with a working human kidney. So his pig kidney bridged him and returned.

SPEAKER_02 57:32

Oh, that's okay. That's an interesting thought, like as the bridge. So my last question, what would have to happen for you to feel ethically uneasy about where this field is going? Because you know, you say all these things, and obviously you want to help someone whose kidney isn't working, who's part of their liver isn't working heart. But then you also mentioned the word longevity at the beginning of the podcast. And then that made my brain, which is a little scary, go to like all these brave new world type of scenarios. So I'm just curious what your Yeah.

SPEAKER_00 58:05

I mean, actually, it's funny you mentioned it because I I've been doing a little writing about this on the side. And um, the truth is if we were using chimpanzees now, we probably could get those organs to work like a human organ. They're probably close enough. But um the dystopian idea of breeding, you know, chimpanzees on an island. I pictured on an island, you know, they breed like we breed in terms of timing and having one baby or sometimes two, is incredibly dystopian. Somehow it feels less dystopian with pigs because, well, a lot of reasons. One, we already breed and sacrifice so many. You know, they have really big litters, um, they breed really quickly. So there's a lot different uh about that. Maybe other people don't feel that way. And I I do think Xeno can actually reach this point. And Martine Rothbard, who's one of the um kind of amazing pioneers who deserves her a million podcasts on her uh about her only. She founded Sirius Radio, kind of conquered space, started a pharmaceutical company to save her daughter, and now is in the Xeno space. So much about her that's fascinating. But she talks about, she's also creating mind clones on the on the computer, so like load it trying to create consciousness.

SPEAKER_03 59:18

Yeah.

SPEAKER_00 59:18

Yeah, that's a whole nother topic I can get into. But she talks about how I want to get it to the point where, you know, just like you bring your car in to get a new muffler or get a new tire, I know nothing about it. You know, you can get your 20,000 checkout, you can get a new, you know, you're you're generally your brain's working good, but you're having heart problems, you can trade your heart out. Your kidneys are doing bad, you trade your kidney out. And it becomes part of this longevity space, where as long as your brain is working and you're not having dementia, you know, you can keep the body going for long periods of time. And I think we could get to the point where you can make bespoke pig organs that are somewhat genetically matched to you that require minimal immunosuppression, and it can be a much more minor deal than doing a heart bypass or the things we do right now to keep people alive. And I think it's actually possible to get to that point. I think, yeah, there is this other side of it all where uh it's like, wait, what are we doing here? We um we just replace organs as they fail using, you know, both an incredible amount of expense and science and animals. And I think there's something to be reckoned with with all of that. So it's easy to get incredibly excited about the science and potential and lose sight of some of those other things. I mean, one of the things I struggle with on top of some of the animal parts is the expense of it. Like we don't put enough money. I mean, if we really wanted to, you know, increase longevity and lifespan in our country, we would put money into public health, into, you know, people that don't have access to healthcare, into poverty and all of those things, which we don't want to spend money on, but then we love spending millions of dollars on this unbelievable science because it's so exciting. And and I do struggle with that. At the same time, I love the science of it and the um excitement of it. So I think the key on the animal side is is what we talked about, was treating with respect, using the smallest number possible, you know, being really thoughtful, having these discussions, making sure that you know, yeah, I don't know. And I I struggle. Anyways, we could talk a lot more about I struggle with our food industry, and it's probably not fair to say, well, don't worry about us, worry about them. But I think until we can tackle some of those challenges, it's hard, it's hard to put my efforts on the Xeno side of it. But um, maybe the expense of it is hard. Sometimes I think about that we can do all these amazing things, but we can't pay for so many things we want to pay for. But I'm an incredible optimist. I think we have so many exciting things going on, both in my field of transplant, but in science in general. And um, I wish we could celebrate more of that and get people excited and optimistic and get great people going into the field. I like that positive narrative. Yeah, well, you're optimistic. That's pretty good. I don't want to be Pollyanna. I have tough days too. And I think, you know, I've I've listened to some of your other podcasts, and there's a lot of dysfunction in our healthcare system that I struggle with as well.

SPEAKER_02 1:02:23

But I have like a dark sense of humor.

SPEAKER_00 1:02:26

Well, I'm with you on that. I'm with you on that. But like what transplant reminds me though, it's it's all about this incredible gift. And whether it's a gift from a deceased donor or a living donor or potentially an animal. I mean, with humans, it's someone saying, Let me let me share this risk with you, let me get sick with you and we'll get better together. That's how I think of like living donors. I'm gonna take risk too. We're gonna go through this together. I think the same gift from a deceased donor, it's this legacy that they're giving. And I love being a part of that gift. Obviously, the animals aren't making that decision themselves. But I think this this beautiful gift of transplant is uh exciting to be a part of.

SPEAKER_02 1:03:03

Yeah, no, I I agree. And I I think it's just it's important to acknowledge the ethical dilemma and you know how people feel and the morality of it all, I guess. I mean, it's it's tough. And obviously, like I know we're talking about xenotransplantation, but if we're talking about the treatment of animals, like I would happily start with, you know, addressing the factory farms and what goes on there and you know that kind of thing. It's just it's all, I don't know, it's hard.

SPEAKER_00 1:03:31

It is very hard. And I'm like when Jane, I don't again, I can't speak for Jane Goodall, but and I don't know where she was at the end of her career, but at you know, when she was speaking at the Xeno conference, she was saying, like, I I wouldn't want animal research to just stop immediately right now because I recognize all the things we shouldn't be able to do, but we need to start working towards minimizing it. I I don't know what she would have said in the last well, you know what's interesting?

SPEAKER_02 1:03:54

I'll I'll say this as someone in public health, like in their whole one health movement. So cultivating empathy for animals can kind of also create that connection with our fellow species, which does matter for our own health and for the you know the health of the planet. So you don't want to objectify too much because we're all related and we see what happens when that goes wrong in different parts of the world. So I do think like having a more empathic all species uh approach is beneficial to society. You know, I don't know. But I also appreciate that the there's folks out there struggling, need organs, and how do we manage all that? And there's you know, there's not like there's never going to be a perfect world, so what do we do? But yeah, this is until we're topic.

SPEAKER_00 1:04:41

I mean, until we become mind clones and then we'll be okay. Uh we're all plugged into the metrics. But I um Yeah, I just will say every lab I've worked in has treated the animals with so much respect and thoughtfulness. And you know, sometimes when these files get leaked, like happened in the 90s with you know, with the Xeno lab, this idea that the abuse and what's going on, uh that's not in my experience, and it's critical that people treat these animals, you know, with respect and care. Um, but in a pr you're right, in a perfect world, we wouldn't need to do these things. But I I think without it, so much of what we rely on in healthcare is based on it. And yeah, I'm all for minimum.

SPEAKER_02 1:05:24

I'm focused on like getting animals out of performing, performing for humans, like you know, like the circus performers. I think so I'm like starting there.

SPEAKER_00 1:05:30

Like you might have seen like the in the early xeno transplants in this.

SPEAKER_02 1:05:35

Yes, I read that in your book.

SPEAKER_00 1:05:36

I actually weren't animals that retired from the circus, or they called them.

SPEAKER_02 1:05:39

I felt so disturbed when I read that in your book because I was like, oh my god, these poor animals they had to perform their entire life, and then they had to go to this early research, you know, or they get sent into space. Like it is it's kind of the dog that was sent into space. Yeah, like you see that picture that goes on the and every time I see that dog in the capsule, I'm like, I hate humans, but like Yeah.

SPEAKER_00 1:06:00

Yeah, we don't deserve we don't deserve animals. That probably is true, but yeah, no, it's it is uh that is a bizarre piece of our history. It is interesting though to th I know it's um out in Portland in Oregon where they have one of the primate centers, they're thinking about closing it and turning it into um yeah, so you know, somewhere where the animals can live or something like that. So it's a debate that is going on right now about that. I just think we need to talk about both sides of the debate then. What what I agree, you know, what can we replace? What are we gonna lose? And are people okay with that? Are people okay with we wouldn't have heart bypass, we wouldn't have organ transplant, we might not have GLP medications, you know, like maybe some of these things we can do without animals, and maybe some of them we can.

SPEAKER_02 1:06:47

Yeah. And that's the other thing. If you just stop all research, like what is not gonna happen and you know, what's not gonna come to light for humans. So it's it's a very tricky subject, but I do appreciate you having a you know a discussion and sharing your thoughts on it. And just I think just bringing all these issues, all of the issues, you know, forward uh is good in having respectful conversation. I know sometimes people can really dig in and like you can't have a respectful conversation, but um that doesn't benefit anybody. Thank you for this. And just I will share the show in the show notes the link for your book. Um and then is it and is it gonna be on Amazon, I guess?

SPEAKER_00 1:07:27

Or yeah, it'll be on it comes out April 7th. It'll be on Amazon and Penguin Random House and MIT, but Amazon's fine. I mean everywhere.

SPEAKER_02 1:07:35

Yeah. Are you expecting to get some like critics because of the topic?

SPEAKER_00 1:07:39

Like I hope so. I mean, I'm doing a few events and I'm trying to reach out to some uh in fact, like I'm doing an event at um Powell's in and I'm trying to get the primate center people to come out in Oregon because uh I think it'd be a really good discussion. I mean, it's a really important topic, and I feel like we're getting there's this massive attack on science, I think, in general and funding science, but there's also like a lot of mixed messages on what the FDA versus the NI interpretation do. And I just don't know if anyone's thinking this through. So it needs to be a good thing.

SPEAKER_02 1:08:12

Maybe RFK listens to this podcast. I don't know.

SPEAKER_00 1:08:15

Yeah, yeah. That maybe I'll send it to him.

SPEAKER_02 1:08:18

I'll send it to his staff. Thanks so much for coming on.

SPEAKER_00 1:08:20

Oh, it's a blast.

SPEAKER_02 1:08:21

Yeah, yeah. And good luck with the book.

SPEAKER_00 1:08:23

Oh, thank you.

SPEAKER_02 1:08:24

And hopefully you won't have to wear any bulletproof vest and that kind of thing. But yeah, I hope not. Hopefully, everyone, hopefully, people will be open to conversations. There we are.

SPEAKER_03 1:08:34

All right, enjoy the rest of your day.

SPEAKER_02 1:08:35

All right, bye-bye.

SPEAKER_03 1:08:36

Bye-bye.

SPEAKER_02 1:08:38

All right, guys, thanks so much for joining in. Please let me know what you thought. Uh, also, the link for Dr. Mesrich's book is in the show notes. I encourage you to grab a copy and read it. If you're on a transplant list or love someone who is, the promise of something like this can feel like hope, but hope in medicine isn't always clean. This conversation doesn't try to tie everything up in a nice bow or make it comfortable. And it's not just about whether we can do this, it's about what it means if we do for people, for animals, and for how we think about both. And I certainly appreciate Dr. Mesric coming on and sharing his perspective. And if you like this episode, you can find more conversations like this on causes or cures, where we take health topics, sometimes complicated ones, and try to think through them without oversimplifying them. Uh, so I hope you subscribe. And if you can, sign up for my newsletter. The link for that is in the show notes. All right, and now it's time for the closing quote. This one is from Edward O. Wilson. And I just I liked it. Here it is. The real problem of humanity is the following We have Paleolithic emotions, medieval institutions, and godlike technology. I'm just kidding. But that one kind of does make you think about, you know, like how fast technology evolves and then kind of how slow we evolve as a species, which doesn't necessarily tie into this episode, but it's certainly, I guess it could, like going back to that brave new world bit you know, we talked about in the podcast. But just makes you think a little bit, right? Like how fast, like AI. AI is like, whoa. And then you're like, are we gonna like be able to control this? I don't know. All right, I'm gonna go off on a tangent here if I don't hit stop. So thanks everybody for being here. I hope to see her next time and goodbye for now.