Biomimetic Microgrooved Methacrylated Silk Fibroin Cartilage Scaffold for Tracheal Injury Repair

Abstract Bioengineered tracheas have shown considerable potential in tracheal injury repair; however, their practical value is limited by challenges in tracheal cartilage regeneration, and postoperative tracheal stenosis remains a common issue. Here, inspired by the 3‐layer structure of the trachea and the multi‐segmental characteristics of its cartilage, a multilayered bioengineered tracheal scaffold (named Sd@d‐ECM/BMSCs/SilMA) with a microgroove structure is designed in this study to repair tracheal defects. In this design, the microgrooved surface of the methacrylated silk fibroin (SilMA) hydrogel provides spatial guidance for the directional growth of bone marrow mesenchymal stem cells (BMSCs) and enhances their adhesion and proliferation. The extracellular matrix of the decellularized cartilage scaffold offers the necessary microenvironment and mechanical support for BMSCs to differentiate into cartilage. Under the influence of the dual‐layer structure (inner and outer), the middle‐layer BMSCs can undergo stable chondrogenic differentiation without any inducing agents. Sd@d‐ECM/BMSCs/SilMA effectively promotes tracheal cartilage formation in a rabbit defect model, reduces the incidence of tracheal stenosis, and substantially improves respiratory function. Sd@d‐ECM/BMSCs/SilMA not only confirms the successful construction of microgroove structures on the surface of the SilMA hydrogel and the effective loading of BMSCs but also demonstrates significant experimental value in tracheal cartilage repair and regenerative medicine.