Prof. Molly Shoichet

PhD FRSC Professor-Chemical Engineering-University of Toronto May 2010
Researcher of the month: 
May 2010

Understanding and treating injuries and diseases that affect the brain and the spinal cord are the final frontier in medicine – and that’s where Molly Shoichet is concentrating her research explorations.

The University of Toronto professor of chemical and biomedical engineering holds a Canada Research Chair in tissue engineering. She specializes in regenerative medicine, designing polymers and other materials that are biologically compatible with the human body and can help deliver stem cells and drugs to the spinal cord, the brain or the retina.

Researchers have long been excited about the potential of stem cells to promote healing. But they have been limited by the difficulty of getting stem cells directly to the injured or damaged areas of the central nervous system, where they can be most effective.

One of Shoichet’s goals is to create devices that help stimulate the body’s existing stem cells to repair tissue damaged by stroke or traumatic injury.

“We know that stem cells in the brain and spinal cord are stimulated just by injury,” says Shoichet. “We’re working on ways not just to stimulate them, but to stimulate them to promote repair.”

Shoichet and the researchers in her laboratory have created tubular sheaths to deliver stem cells directly to the location of a spinal injury, protecting the stem cells so they don’t die before they reach the affected areas.

“These are the biggest challenges that we face in the field, because we might be able to transport them, but if they don’t survive and don’t become part of the tissue, then they will have a limited effect and limited benefit to the patient,” she explains.

Although the sheaths appear to work well, implanting them in people still requires invasive surgery – so Shoichet is also working on ways to deliver drugs that are less invasive. She is collaborating with a developmental biologist, for example, to place stem cells directly in the retina, a technology that may one day help to reduce blindness.

In addition, Shoichet and her team have designed a local drug delivery system to send drugs directly to the spinal cord. The system involves a viscous material they can inject through a needle the size of a human hair, which then gels upon injection and will localize wherever it is injected.

“If you’ve got drugs dispersed through it, (the gel) will localize the drug right where you’ve injected it,” Shoichet says. “We can achieve localized delivery of molecules, of proteins, that wouldn’t otherwise cross the spinal cord.”

The gel, composed of hyaluronan, a material that promotes tissue repair, and methyl cellulose, has anti-inflammatory properties and has so far been tested in animal models. Although Shoichet and her team are not yet ready for clinical trials to test their gel’s properties in repairing spinal cord injuries, they are exploring the technology’s commercialization. They are also using the same type of gel formulation to deliver stem cells. Named one of Canada’s Top 40 researchers under age 40 in 2001, Shoichet is frequently invited to lecture all over the world, and has produced more than 350 peer-reviewed publications, patents and abstracts. She enjoys collaborating across many disciplines, such as her work with cancer researchers to deliver chemotherapy directly to cancerous tissue, and not throughout the rest of the body, so that it doesn’t harm otherwise healthy cells. Shoichet has designed new polymers that form nanospheres – tiny spherical structures – that can encapsulate drugs, and be dispersed in the hydrogels. Shoichet hopes this technology and delivery system will help physicians to selectively kill cancer cells and prevent patients from suffering the debilitating effects of chemotherapy that some have found as difficult as the cancer itself. “We’re still in the thick of those studies,” Shoichet says. Shoichet’s venture into cancer research was prompted by the premature death of a good friend, who died of breast cancer in her early 30s. “I was inspired to think, ‘how can my work in polymers and drug delivery make a difference in the field of cancer?’ That was more personal,” says Shoichet. But all of Shoichet’s work is driven by her desire to translate her research into products that benefit people. “We haven’t commercialized anything yet, but that’s the goal,” she says. “It’s a long process, but it’s exciting.”

For further information, please contact Prof. Molly Shoichet at