Preparation of a novel acellular vascular matrix scaffold and its repair effect on medial meniscus defects in rabbits.

Research on the repair and regeneration of injured menisci has remained a focal point of investigation. This study explored the preparation method of a novel acellular vascular matrix (AVM) scaffold and analyzed and evaluated its physicochemical properties as well as its repair effect on medial meniscus defects in rabbits. Histological staining results of the AVM scaffold prepared by a self-designed triple (physical, chemical, and enzymatic) decellularization protocol were similar to those of normal meniscus. Collagen quantification confirmed no statistically significant difference in collagen content between the AVM scaffold and normal tissue. Hoechst 33258 staining results showed no visible residual nuclei in the decellularized vascular matrix, suggesting effective removal of cellular components. Toluidine blue and Sirius red staining confirmed that the AVM scaffold effectively preserved glycosaminoglycans and collagen components. MTT assay results demonstrated that the decellularized arterial matrix was non-cytotoxic and was non-cytotoxic, indicating the absence of residual chemical reagents harmful to cell viability. Scanning electron microscopy (SEM) results showed that after meniscal cell seeding, the AVM scaffold effectively promoted cell adhesion and effectively supported cell adhesion and spreading, indicating a favorable surface environment for cell-scaffold interaction. Three months' post-implantation, X-ray imaging revealed no significant difference in joint space between the AVM scaffold group and the normal control group. Magnetic resonance imaging (MRI) demonstrated the presence of newly formed meniscal tissue and well-preserved articular cartilage. In conclusion, the self-designed decellularization protocol effectively removed major antigenic components from the vascular tissue, and no residual DNA or cellular debris was detectable by Hoechst 33258 staining (within its detection limit), while most extracellular matrix components, intact tissue architecture, favorable mechanical properties, and good cytocompatibility were preserved. Further in vivo animal experiments confirmed that the novel AVM scaffold exhibited a good protective effect on articular cartilage and promoted meniscal repair and regeneration.