Cartilage-derived morphogenetic proteins have an important regulatory role in inducing cell differentiation and promoting cartilage repair. Subchondral drilling for treating cartilage defects in clinical practice has been widely used, but the related study on combined application of the cartilage-derived morphogenetic protein-1 (CDMP-1) and other factors is less.OBJECTIVE:
To combine the subchondral drilling technology with hyaluronic acid-coated CDMP-1 (HA/CDMP-1) microspheres for observation of their effects on the repair of cartilage defects, and meanwhile to compare the therapeutic effects among combination group, subchondral drilling group and HA/CDMP-1 group as well as to observe whether there is a synergistic effect.METHODS:
HA/CDMP-1 microspheres were prepared and cryopreserved. Full-thickness articular cartilage defect models were prepared in rabbits, and then the model rabbits were divided into model group (intra-articular injection of normal saline), subchondral drilling group (subchondral drilling), HA/CDMP-1 group (intra-articular injection of HA/CDMP-1), combination group (subchondral drilling+intra-articular injection of HA/CDMP-1).RESULTS AND CONCLUSION:
At 8, 12, 16 weeks after modeling, histological observations suggested that the coverage area of repair tissue was higher in the combination group than the other groups (P < 0.05). Toluidine blue staining and quantitative PCR showed that the mRNA expression of proteoglycan and type II collagen was also significantly higher than in the combination group than the other groups (P < 0.01 or P < 0.05). These findings indicate that the intra-articular injection of HA/CDMP-1 combined with subchondral drilling can promote the repair of articular cartilage damage effectively, suggesting a possible synergy between them.