December 14, 2016 – Credit: Marit Mitchell / U of T Engineering
Time may not heal all wounds, but a proprietary mix of peptides and gel developed by U of T Engineering researchers heals most.
A team led by Professor Milica Radisic has demonstrated for the first time that their peptide-hydrogel biomaterial prompts skin cells to “crawl” toward one another, closing chronic, non-healing wounds often associated with diabetes, such as bed sores and foot ulcers.
The team tested their biomaterial on healthy cells from the surface of human skin, called keratinocytes, as well as on keratinocytes derived from elderly diabetic patients. They saw non-healing wounds close 200 per cent faster than with no treatment, and 60 per cent faster than treatment with a leading commercially used collagen-based product.
“We were happy when we saw the cells crawl together much faster with our biomatieral, but if it didn’t work with diabetic cells, that would have been the end of the story,” says Radisic. “But even the diabetic cells travelled much faster — that’s huge.”
Until now, most treatments for chronic wounds involved applying topical ointments that promote the growth of blood vessels to the area. But in diabetic patients, blood vessel growth is inhibited, making those treatments ineffective. Radisic and her team have been working with their special peptide — called QHREDGS, or Q-peptide for short — for almost 10 years. They knew it promoted survival of many different cell types, including stem cells, heart cells and fibroblasts (the cells that make connective tissues), but had never applied it to wound healing.
“We thought that if we were able to use our peptide to both promote survival and give these skin cells a substrate so they could crawl together, they would be able to close the wound more quickly,” says Radisic. “That was the underlying hypothesis.”
