Pig's organ in human body? Xenotransplantation

Anyway, coming back to Five Feet Apart, the two protagonists in the film suffer from cystic fibrosis 🫁, a genetic disorder. People with this condition produce an excessive amount of mucus in their lungs and digestive system, which leads to difficulty breathing and digestive problems. In the movie, both characters desperately wait for a lung transplant, but it’s not easy because there are far fewer organ donors than there are people waiting. (Of course, the real-world situation is slightly different, but let’s not dive too deep into that today. We have an even more fascinating and controversial topic to explore!)

Photo: Haley Lu Richardson in Five Feet Apart. Photograph by Alfonso Bresciani/Alfonso Bresciani/Vertigo Releasing

Organ Donation: The Wall Between Demand and Supply

Reality is not much different from the movie. As of the end of 2024, 54,780 people in Korea were waiting for an organ transplant, but there were only 397 brain-dead donors. About 400 heroes saved other lives before they left, yet countless patients are still waiting for a chance to live. Organ donation requires highly strict procedures regarding the condition and preservation of the organs. Unless it’s a living donation, like a partial liver transplant, most transplants use organs from brain-dead or recently deceased donors. In reality, the number of organs that meet all these medical conditions is far smaller than the number of patients who need them.

The Proposed Solution: Xenotransplantation

To solve this imbalance, scientists have suggested a groundbreaking alternative: xenotransplantation which is transplanting organs from a different species. Given the huge demand but extremely limited human donors, researchers are exploring the use of pig organs to overcome the shortage. It sounds fascinating but also hard to imagine.

How is this actually possible, and is it truly safe and ethical?

How Can Xenotransplantation Work?

“Xeno” literally means “different species.” For example, transplanting fish skin onto a dog would technically be xenotransplantation. Recently, attention has turned to using pig organs 🐖 for human transplants because pigs are easy to breed and their organs are physiologically similar to ours. But how can a pig’s organ even function in a human body? The answer lies in gene editing 🧬.

Each biotech company developing xenotransplantable pig organs edits different genes, but the general idea is to remove problematic genes and insert human-compatible ones. The edited DNA is inserted into a pig’s egg cell, which is then implanted into a surrogate mother pig. After pregnancy, the piglets born with the edited genes are raised in sterile facilities specifically for transplantation purposes.

How Successful Has Xenotransplantation Been So Far?

Early surgeries failed due to strong immune rejection, and recipients often died shortly after. Thanks to gene editing, survival times have extended — from just days to weeks, and now even months — but not yet to years.

You might think, “Then isn’t xenotransplantation hopeless?” 🤷 But in 2024, a woman in her 50s in the U.S. successfully lived four months with a transplanted pig kidney that functioned perfectly during that time. After four months, the transplanted kidney stopped working and was removed, but she recovered through dialysis and regained her health. Her case has given scientists hope — showing that xenotransplantation might serve as a “bridge therapy” that can buy time for patients awaiting human organs.

Is Xenotransplantation Safe?

Here’s the ultimate question: Is it safe?

The biggest concern is zoonotic infection 🧪, specifically the possibility that a porcine endogenous retrovirus (PERV) in pig DNA could infect humans. Because this virus is embedded in the pig’s genome 🧬, it can’t be completely removed just by raising pigs in sterile environments. This makes it one of the key barriers to safe xenotransplantation.

Moreover, most recent pandemics such as COVID-19, Ebola, MERS, SARS have been caused by zoonotic diseases. This unpredictability makes people even more cautious. As a result, researchers are taking multiple safety measures, such as advanced gene editing and sterile breeding, to minimize infection risks.

❓Can Organ Transplants Transmit Diseases?

In fact, organ transplantation is one of the most direct transmission routes for infection, since infected tissue is being implanted directly into another body. For instance, HIV cannot be transmitted through saliva, but it can be transmitted through blood transfusion or organ transplantation. That’s why it’s considered a potential infection pathway.

So… What’s the Verdict on Xenotransplantation?

There are countless debates surrounding xenotransplantation. Some oppose it for ethical or scientific reasons,
while others support it as a realistic solution to the organ shortage crisis. Right now, there aren’t enough human cases to draw solid conclusions, but as more studies and examples accumulate, we’ll be closer to understanding whether it’s truly viable. Until then, xenotransplantation remains one of the most fascinating and controversial frontiers of modern biology. See you next time with another story from the world of science 🙌