Degradation Of Silk Fibroin And The Application Of3D-printed Bio-inducible Scaffold In Skin Tissue Engineering

As a tissue engineering material, the degradation of silk fibroin has been controversial. This study investigated on the degradation speed and degradation pathway of silk. Based on the results, a new silk fibroin scaffold was designed and tested for the repair of soft tissue.The key problem hindering skin repair are deficient of dermal vascularization which provides oxygen and nutrients to the injured skin, and difficulty of epidermis regeneration, it is challenging to fabricate scaffolds that can biologically fulfill the requirements for regeneration of skin injuries. To solve this problem, we developed a three-dimensional printed hydrogel-silk fibroin (3DG-SF) matrix scaffold incorporated with basic fibroblast growth factor (FGF-2) through a sulfonic acid group (SO3). The efficacy and mechanism by which the3DG-SF-SO3-FGF scaffolds promote skin regeneration were systematically investigated both in cell culture and in a full-thickness skin defect models. The histological results showed that incorporation of FGF-2into3D scaffolds significantly enhanced the regeneration of skin-like tissues as compared to petroleum gauze, after implantation in rat skin defects for14and28days. Further investigations demonstrated that FGF-2from the3DG-SF-FGF scaffolds might play a key role in stimulating the vascularization of dermis. These findings thus suggest that the incorporation of FGF-2into3DG-SF-SO3scaffolds is a favorable strategy for regenerating skin.