Tag Archives: Cari Shane

Asparagus spinal cord?

I love this picture,

Pelling in the kitchen with asparagus, the veggie that inspired his work on spinal cord injuries. Credit: Andrew Pelling?

The image accompanies Cari Shane’s August 4, 2021 article for Atlas Obscura’s Gastro Obscura about Andrew Pelling and his asparagus-based scaffolds for spinal cord stem cells (Note: A link has been removed),

Around 10 years ago, Pelling [Dr. Andrew Pelling at the University of Ottawa], a biophysicist, started thinking with his team about materials that could be used to reconstruct damaged or diseased human tissues. Surrounded by a rainbow of fresh fruits and vegetables at his University of Ottawa lab, Pelling and his team dismantle biological systems, mixing and matching parts, and put them back together in new and creative ways. It’s a little bit like a hacker who takes parts from a phone, a computer, and a car to build a robotic arm. Or like Mary Shelley’s Dr. Frankenstein, who built a monster out of cadavers. Except Pelling’s team has turned an apple into an ear and, most recently, a piece of asparagus into a scaffold for spinal-cord implants.

Pelling believes the future of regenerative medicine—which uses external therapies to help the body heal, the same way a cut heals by itself or a broken bone can mend without surgery—is in the supermarket produce aisle. He calls it “augmented biology,” and it’s a lot less expensive—by thousands and thousands of dollars—than implanting organs donated by humans, taken from animals, or manmade or bioengineered from animal tissue.

Decellularization as a process for implantation is fairly new, developed in the mid 1990s primarily by Doris Taylor. By washing out the genetic materials that make an apple an apple, for example, you are left with plant tissue, or a “cellulose mesh,” explains Pelling. “What we’re doing is washing out all the plant DNA, RNA proteins, all that sort of stuff that can cause immune responses, and rejection. And we’re just leaving behind the fiber in a plant—like literally the stuff that gets stuck in your teeth.”

When Pelling noticed the resemblance between a decellularized apple slice and an ear, he saw the true potential of his lab games. If he implanted the apple scaffolding into a living animal, he wondered, would it “be accepted” and vascularize? That is, would the test animal’s body glom onto the plant cells as if they weren’t a dangerous, foreign body and instead send out signals to create a blood supply, allowing the plant tissue to become a living part of the animal’s body? The answer was yes. “Suddenly, and by accident, we developed a material that has huge therapeutic and regenerative potential,” says Pelling. The apple ear does not enable hearing, and it remains in the animal-testing phase, but it may have applications for aesthetic implantation.

Soon after his breakthrough apple experiment, which was published in 2016 and earned him the moniker of “mad scientist,” Pelling shifted his focus to asparagus. The idea hit him when he was cooking. Looking at the end of a spear, he thought, “Hey, it looks like a spinal cord. What the hell? Maybe we can do something,” he says.

… Pelling implanted decellularized asparagus tissue under the skin of a lab rat. In just a few weeks, blood vessels flowed through the asparagus scaffolding; healthy cells from the animal moved into the tissue and turned the scaffold into living tissue. “The surprise here was that the body, instead of rejecting this material, it actually integrated into the material,” says Pelling. In the bioengineering world, getting that to happen has typically been a major challenge.

And then came the biggest surprise of all. Rats with severed spinal cords that had been implanted with the asparagus tissue were able to walk again, just a few weeks after implantation. …

While using asparagus tissue as scaffolding to repair spinal cords is not a “miracle cure,” says Pelling, it’s unlike the kinds of implants that have come before. Donated or manufactured organs are historically both more complicated and more expensive. Pelling’s implants were “done without stem cells or electrical stimulation or exoskeletons, or any of the usual approaches, but rather using very low cost, accessible materials that we honestly just bought at the grocery store,” he says, “and, we achieved the same level of recovery.” (At least in animal tests.) Plus, whereas patients usually need lifelong immunosuppressants, which can have negative side effects, to prevent their body from rejecting an implant, that doesn’t seem necessary with Pelling’s plant-based implants. And, so far, the plant-based implants don’t seem to break down over time like traditional spinal-cord implants. “The inertness of plant tissue is exactly why it’s so biocompatible,” says Pelling.

In October 2020, the asparagus implant was designated as a “breakthrough device” by the FDA [US Food and Drug Administration]. The designation means human trials will be fast-tracked and likely begin in a few years. …

Shane’s August 4, 2021 article is fascinating and well illustrated with a number of embedded images. If you have the time and the inclination, do read it.

More of Pelling’s work can be found here at the Pelling Lab website. He was mentioned (by name only as a participant in the second Canadian DIY Biology Summit organized by the Public Health Agency of Canada [PHAC]) here in an April 21, 2020 posting (my 10 year review of science culture in Canada). You’ll find the Pelling mention under the DIY Biology subhead about 20% of the way down the screen.