EGF-supplemented decellularized tracheal matrix hydrogels promote tracheal defect repair

BACKGROUND: Tracheal defect repair is a major clinical challenge in thoracic surgery, with long-segment defects having a low clinical repair rate. Autologous cartilage transplantation is limited by high postoperative stenosis and insufficient autologous tissue, while traditional artificial tracheal materials have poor biocompatibility and no epithelial regeneration-inducing capacity, leading to poor long-term efficacy. This study aimed to fabricate a biomimetic composite hydrogel and evaluate its physicochemical properties and tracheal repair efficacy, providing a new tissue-engineered strategy for clinical tracheal defect management. METHODS: A PEGDA/DCM/EGF composite hydrogel was prepared via photopolymerization. Its physicochemical properties and EGF release pattern were characterized. In vitro experiments on rat tracheal epithelial cells assessed cell viability, proliferation and migration. A tracheal defect model was established in SD rats, with the hydrogel implanted; gross observation, HE staining and immunohistochemistry were performed at 2 weeks post-implantation to evaluate repair efficacy, with statistical methods used for intergroup comparisons. RESULTS: The PEGDA/DCM hydrogel had optimized microstructure and mechanical properties matching native trachea, maintained structural stability under physiological conditions, and achieved sustained EGF release without burst effect. The PEGDA/DCM/EGF hydrogel significantly promoted the viability, proliferation and migration of rat tracheal epithelial cells in vitro. In vivo, implanted SD rats had intact tracheal architecture and unobstructed lumens at 2 weeks; HE staining and immunohistochemistry confirmed continuous epithelial layer formation and successful epithelialization at the defect site. CONCLUSIONS: The PEGDA/DCM/EGF composite hydrogel has favorable physicochemical properties, excellent biocompatibility and effective tracheal repair efficacy, with DCM optimizing hydrogel performance and sustained EGF release accelerating epithelial regeneration. This study provides a promising tissue-engineered strategy for tracheal defect repair, with significant clinical translation potential for thoracic surgery clinical practice.