Effect of collagen-based scaffolds with hydroxyapatite on the repair of cartilage defects in the rabbit knee joint

The repair of articular cartilage defects is always a significant clinical challenge in joint treatment. Therefore, the aim of this study was to investigate that the ColII-HA-CS-HAP scaffolds with BMSCs could repair cartilage defects of knee.

Bone marrow mesenchymal stem cells (BMSCs) were extracted from rabbits, identified using immunofluorescence staining, and successfully induced into chondrocytes. Type II collagen (ColII) was isolated from bovine cartilage and constructed into scaffolds with hyaluronic acid, chondroitin sulfate, and hydroxyapatite. Then BMSCs were seeded on the ColII-HA-CS-HAP scaffold to detect biocompatibility.

The results of DAPI fluorescence staining showed that the number of BMSCs on the ColII-HA-CS-HAP scaffolds increased rapidly after culturing for 12 d. The rabbit knee cartilage defect model with a diameter of approximately 3 mm and a thickness of approximately 4 mm was selected to evaluate the regenerative potential of the scaffolds using histological and immunohistochemical analyses. At 6 months, the regenerated cartilage in the ColII-HA-CS-HAP scaffolds with BMSCs was more similar to that of native cartilage than the ColII-HA-CS-HAP scaffold group.

Our study proved that the ColII-HA-CS-HAP scaffolds with differentiated BMSCs can produce an excellent healing response and repair cartilage defects successfully in a rabbit model.