Thermoresponsive material allows slow release of SDF-1 at the wound site to promote healing
Foot ulcers affect approximately 15% of diabetes patients and can cause serious complications, with almost a quarter of cases resulting in lower-leg amputation. A team of Engineers from Northwestern University (IL, USA) has attempted to address this serious complication through the development of a regenerative bandage, which aims to promote and speed wound healing.
In this latest study, the group used a previously created thermoresponsive material able to deliver therapeutic cells and proteins. Led by Northwestern’s Guillermo Ameer, researchers used this material to slowly release the chemokine SDF-1 into the wound site in the hope that SDF-1 would encourage wound healing through promotion of endothelial progenitor cell homing and angiogenesis.
“We incorporated a protein that our body naturally uses to attract repair cells to an injury site,” explained Ameer. “When the protein is secreted, progenitor cells or stem cells come to the wound and make blood vessels, part of the repair process.”
The thermoresponsive material used in this study is applied to the wound as a liquid but solidifies into a gel upon exposure to body temperature, allowing slow release of the therapeutic protein. “The ability of the material to reversibly go from liquid to solid with temperature changes protects the wound,” Ameer summarized. “Patients have to change the wound dressing often, which can rip off healing tissue and re-injure the site. Our material conforms to the shape and dimensions of the wound and can be rinsed off with cooled saline, if needed. This material characteristic can protect the regenerating tissue during dressing changes.”
Using this technique, the researchers reported an improved closure rate of dermal wounds in diabetic animals. It is hoped these findings show promise as a new approach to treating for diabetic foot ulcers.
Written by Hannah Wilson
Sources: Zhu Y, Hoshi R, Chen S, et al. Sustained release of stromal cell derived factor-1 from an antioxidant thermoresponsive hydrogel enhances dermal wound healing in diabetes. J Control Release. 238: 114—122 (2016); Northwestern University News www.mccormick.northwestern.edu/news/articles/2016/08/regenerative-bandage-heals-diabetic-wounds-faster.html