Effect of glutaraldehyde‐crosslinked cartilage acellular matrix film on anti‐adhesion and nerve regeneration in a rat sciatic nerve injury model

Decellularized extra‐cellular matrix (ECM) has been studied as an alternative to anti‐adhesive biomaterials and cartilage acellular matrix (CAM) has been shown to inhibit postoperative adhesion in several organs. This study aimed to evaluate the suitability of glutaraldehyde (GA) crosslinked CAM‐films as anti‐adhesion barriers for peripheral nerve injury. The films were successfully fabricated and showed improved physical properties such as mechanical strength, swelling ratio, and lengthened degradation period while maintaining the microstructure and chemical composition after GA crosslinking. In the in vitro study of CAM‐film, the dsDNA content met the recommended limit of decellularization and more than 70% of the major ECM components were preserved after decellularization. The adhesion and proliferation of seeded human umbilical vein endothelial cells and fibroblasts were significantly lower in CAM‐film than in control, but similar with Seprafilm. However, the CAM‐film extract did not show cytotoxicity. In the in vivo study, the peri‐neural fibrosis was thicker, adhesion score higher, and peri‐neural collagen fibers more abundant in the control group than in the CAM‐film group. The total number of myelinated axons was significantly higher in the CAM‐film group than in the control group. The inflammatory marker decreased with time in the CAM‐film group compared to that in the control group, whereas the nerve regenerative marker expression was maintained. Moreover, the ankle angles at contracture and toe‐off were higher in the CAM film‐treated rats than in the control rats. GA‐crosslinked CAM films may be used during peripheral nerve surgery to prevent peri‐neural adhesion and enhance nerve functional recovery.