Investigation of Dermis-derived Hydrogels for Wound Healing Applications

Background: Wound healing and skin tissue engineering are mediated, in part, by interactions between cells and the extracellular matrix (ECM). A subset of the ECM, basement membranes (BM), plays a vital role in regulating proper skin healing and function. Methods: ECM-rich, tissue-specific hydrogels were extracted and assembled from dermis samples. These hydrogels contain BM proteins vital to skin regeneration, including laminin beta 3, collagen IV, and collagen VII. The extracts could be assembled to form hydrogels by either temperature or pH mechanism, with the mechanical properties and structure varying with the mechanism of assembly. A wound healing model was developed to investigate the ability of these hydrogels to enhance healing with a single application in vivo. Results: The pH, but not temperature gels were easily applied to the wounds. There were no signs of increased inflammation due to the application of the hydrogels. The width of granulation tissue at the first week was reduced (p = 0.064) relative to controls with the application of hydrogel. There were no changes in wound closure rates or vessel density. Conclusions: Dermis-derived hydrogels contain BM proteins important for skin regeneration. They can be easily applied, but their poor mechanical strength and rapid degradation may hinder their biological effects.