A Preliminary Research On The Articular Cartilage Defects Repairment In Rabbits By Using The Integrative Poly (Hydroxybutyrate-co-ydroxyoctanoate)/Collagen Osteochondral Scaffold

Background:Due to its complicated physiological characteristics of cartilage tissue, the clinical treatment effect of articular cartilage injury is unsatisfactory. In recent years, With the rapid development of medical research,methods and means for tissue engineering have become a new treatment model for repairing articular cartilage injury, providing a new idea for clinical repair of articular cartilage defect. Objective:Discussion the integrative poly(hydroxybutyrate-co-hydroxyoctanoate/co-llagen)ost eochondral tissue-engineering scaffold on repair of rabbit articular cartilage injury. Methods:To take PHBHOx as basic material, mixed with some proportion of collagen, and adopt the solvent casting/particulate leaching method to fabricate the three-layer integrated osteochondral scaffold, which is co-cultured with the isolated, cultured rabbit knee chondrocytes. The 24 4-week-old healthy white rabbits from New Zealand are selected to carry out combined anesthesia, and then separated layer by layer till their articular surface of the femoral condyles is exposed. The electric bone drill is performed on their intercondylar parts to create articular cartilage defects(4.5 mm in diameter, and 5mm in depth). Then they are processed accordingly after randomization(blank group: suture the injury; control group: implant stent alone in the injured part; the experimental group: implant the scaffold-chondrocyte complex in the injured part). After 12 weeks and 24 weeks respectively, the femoral condyles are removed to observe the repair condition of cartilage injury through appearance and histologiy. Results:The wound heals properly after the operation, no redness, no rupture, and the knee move and gait tended to be normal a week after the operation. After 12 weeks, the defects of the experimental group are covered with transparent film-like tissues, and the histology stain shows the cells are small and irregular; the defects of the control group are more obvious, mainly fibrous tissue; the defects of the blank group had no obvious traces of rehabilitation. After 24 weeks, the defects of the experimental group are covered with transparent film-like tissues, and the cells are regular; the defects of the control group are covered with white membranous tissues, and cartilage-like cells can be found at the base and edge; in the defects of the blank group a small amount of new issues can be seen. Conclusion:The integrative poly osteochondral tissue-engineering scaffold,which composited seed cells,could promote the repair of articular cartilage injury.