Ellipsoidal porous patch with anisotropic cell inducing ability for inhibiting skin scar formation

Scar formation has always been a difficult point to overcome in the field of clinical wound care. Here, we present an ellipsoidal porous patch with cell inducing ability for inhibiting scar formation. The patch was prepared by stretching a poly (lactic-co-glycolic acid) (PLGA) inverse opal film at the glass transition temperature to form a neatly arranged three-dimensional ellipsoidal porous structure. Such anisotropic structure showed dramatic capability in directing cell growth and arrangement by reconstructing cell morphology. Besides, the proliferation of cells growing on the stretched patch was significantly suppressed without cell cytotoxicity. In addition, benefitting from the abundant and connected nanopores, the patch could be imparted with a potent ability to promote cell migration by encapsulating fibroblast growth factor 2 (FGF2) via the second filling of functional gelatin methacryloyl (GelMA) hydrogel into its scaffold. In a typical scar model, we have demonstrated that the resultant patch performed well in inhibiting scar formation characterized by inhibiting the excessive proliferation of fibroblasts, decreasing the deposition of type I collagen, reducing the scar index and achieved complete tissue reconstruction. These results indicate the anisotropic inverse opal patch has an excellent application prospect in inhibiting scar formation during wound repair.