Injectable composite microspheres/hydrogel membranes for Achilles tendon regeneration

Tendon injury is a common condition with potential for disability. Severe injuries such as tendon rupture often require surgical suturing to restore their structure and function. The healing process of tendons is a critical factor affecting clinical outcomes; however, their poor blood supply and low cellular density limit self-regeneration capabilities. This leads to insufficient quality and biomechanical properties of the repaired tendon, playing a significant role in the high rate of re-rupture in clinical practice. Tendon healing involves endogenous (tenocyte proliferation) and exogenous (fibroblast invasion) mechanisms. An imbalance between these two mechanisms often leads to postoperative adhesions, which significantly impacts clinical efficacy. Thus, this project aims to design an injectable, sustained-release methacryloyl gelatin (GelMA) hydrogel microsphere modified with Platelet-Derived Growth Factor-BB (PDGF-BB) and fibronectin (Fn), in conjunction with an anti-adhesion hyaluronic acid methacrylate (HAMA) hydrogel membrane. This combination is designed to promote tendon healing and prevent adhesions. This study will utilize an Achilles tendon rupture animal model to assess the effectiveness of composite microspheres/hydrogel membranes in enhancing tendon repair and preventing adhesions, offering insights for new clinical strategies in tendon rupture treatment. Schematic diagram: Preparation of PDGF&Fn-GelMA hydrogel microspheres and HAMA hydrogel. Implantation composite microspheres/hydrogel membranes into rat injured tendon to promote tendon healing and prevent adhesion tissue formation. (PDGF-BB, Platelet-Derived Growth Factor-BB; Fn, fibronectin.