Why you should care
Because one day we might be able to rebuild our bodies using materials found in our kitchens.
We’re facing a staggering donor organ shortage. In the United States alone, more than 120,000 patients are waiting for a transplant, according to the Department of Health and Human Services. Every day, an estimated 21 people die while waiting for organs that never come.
Being able to grow organs from a patient’s own stem cells would help, and scientists are well on their way to making specialized stem cells that could be seeded onto a scaffold and become livers, or hearts, or skin. One remaining challenge: the scaffolds themselves. Traditional methods, which involve building them from animals, cadavers or proprietary materials, are complex and expensive. Which is why biohacker and avid dumpster-diver Andrew Pelling has begun plumbing a cheaper, more accessible source: the compost bin.
In a just-released TED Talk, Andrew Pelling describes how his lab grows human tissue on ears whittled from apples.
Seriously. Check it out around the second minute of Pelling’s TED Talk. He and his colleagues at the University of Ottawa are looking at other produce too, like asparagus, which could help repair spinal cord injuries. “It’s a good lab, man,” Pelling says, laughing.
Pelling and his lab members didn’t intend to grow ears from apples. The idea stemmed from a conversation they had about Audrey II, the giant monster flytrap from the cult horror/black comedy/musical Little Shop of Horrors. “Could we grow Audrey II in the lab?” they wondered. Ph.D. student Daniel Modulevsky started working with leaves, removing their cells from the cellulose scaffold that gives plants their structure. But he had trouble when it came to stripping the leaves’ waxy coating. When he spotted another lab member eating an apple one day, a lightbulb went off. Why not use apples instead? He could even peel them and carve them into objects.
After removing the cells from apples, the lab members seeded the remaining cellulose scaffold with mouse and human cells. They first seeded them on tiny squares they had prepared themselves. Later, they grew them on ears that Pelling’s wife, a musical-instrument-maker, had fashioned from McIntosh apples for an art exhibit at the University of Western Australia. They also implanted them in mice, whose bodies populated them with cells and blood vessels.
In his TED Talk, Pelling describes his lab’s investigation into whether severed neurons can be guided back together through the channels in asparagus spears. Pelling and his colleagues have launched pilot experiments to determine whether implanting asparagus in the spines of injured rats will help them recover motor function. They’re also studying the properties of cellulose scaffolds in mushrooms, pears, flower petals and tofu. Pelling wonders whether one day nonscientists could make these implants at home and repair or modify their own bodies. He recently teamed up with Modulevsky and postdoctoral fellow Charles Cuerrier to launch Spiderwort, a company that sells open-source kits for making cellulose-derived biomaterials and growing mammalian cells.
Whether patients can use these scaffolds still hinges on how they fare in animal and, later, human implantation trials, says John Haycock, director of the Centre for Biomaterials & Tissue Engineering at the University of Sheffield: “Can you sterilize it? What’s the tissue’s response?” Still, the data in the PLOS ONE paper that describes how Pelling’s team grew mammalian cells on apple-derived scaffolds is “robust,” Haycock says. “It’s a quirky, interesting study.” As he read it, he wondered, “Why hasn’t someone thought of this before?”
Chalk it up to Pelling’s unconventional approach. Unlike most lead investigators who dictate their lab’s research trajectory, Pelling turns his lab members loose to explore what they’re curious about, even if it doesn’t have a practical application. (Case in point: He’s curious about using plant-derived implants for horns and other body modifications.) He cites play as a crucial part of his practice and wants to highlight the value of pursuing curiosity for its own sake, “not because we can save a lot of lives,” although it can yield lifesaving discoveries. The widespread disdain for play as “not serious” could kill innovation, Pelling argues.
“It’s totally legitimate in my lab to have a discussion about Little Shop of Horrors and figure out how to build that monster plant,” Pelling says. “That’s science at its heart.”