羟基丁酸-羟基辛酸共聚体/胶原骨软骨一体化支架修复膝关节软骨损伤

Poly(hydroxybutyrate-co-hydroxyoctanoate/collagen) osteochondral tissue-engineered scaffold used for repair of knee cartilage injury

BACKGROUND: Due to the complex physiological characteristics of the osteochondral tissue, the clinical repair of knee cartilage injury often has dissatisfied outcomes. Tissue engineering methods and tools provide a new idea for osteochondral repair. OBJECTIVE: To observe the effect of poly(hydroxybutyrate-co-hydroxyoctanoate/collagen) osteochondral tissue-engineered scaffold on the repair of articular cartilage injury in a rabbit. METHODS: The poly(hydroxybutyrate-co-hydroxyoctanoate/collagen) osteochondral tissue-engineered scaffold was prepared by solvent casting/particle leaching method. Then, seed cells were isolated and cultured on the scaffold. Twenty-four healthy New Zealand white rabbits, 4 weeks of age, were used for the study. Under balanced anesthesia, an articular cartilage defect (4.5 mm in diameter, 5 mm in depth) was created on the rabbit’s femoral condyle using a bone drill. After modeling, rabbits were randomized into three groups and given direct suture in blank group, pure scaffold implantation in control group and implantation of the scaffold-cell complex in experimental group. Femoral condyle of each rabbit was taken out for gross and histological observations at 8, 20 weeks after surgery. RESULTS AND CONCLUSION: At 8 weeks after surgery, transparent film-covered defects and small/irregular cells were found in the experimental group; the defects were filled with fibrous tissues in the control group; while there was no repair in the blank group. Until the 20th week, the defects were covered with hyaline cartilage-like tissues, accompanied by regular cell arrangement in the experimental group; in the control group, the defects were covered with white membranous tissues, and many chondrocytes were found at the basement and edge; in the blank group, some newborn tissues were visible at the defect region. These findings suggest that the poly (hydroxybutyrate-co- hydroxyoctanoate/collagen) osteochondral tissue-engineered scaffold carrying seed cells contributes to articular cartilage repair.