| The loss of cartilage can be resulted from injuries or surgical excision because of diseases. Given the well-known limitations of cartilage repair, many investigators have attempted to the search for methods of restoring the cartilage loss, but less effective methods can be applied for its therapy. In the past years, tissue engineering, a promising method for regeneration of tissue and organs, were introducing for the repair of cartilage. In this study, it was investigated about the fabrication of neocartilage, effects of bFGF and IGF-1 on chondrocytes and the repair of articular cartilage defects.Experiment 1: Neocartilage by culture of chondrocytes in cultivation tubes with no scaffolds[Abstract] Objective: The formation of neocartilage was investigated by incubating chondrocytes in three-dimension environment with no scaffolds. Method: Mass of chondrocytes was prepared by slow speed centrifugation of chondrocytes isolated by enzyme digestion from rabbits' auricular cartilage, 3mm in diameter and 1mm in thickness. The mass were incubated for 4, 8, 12 weeks in vitro, and the formation of neocartilage were observed histological by species stained with H&E and alcian blue. The total amount of GAG was analyzed biochemically. Results: The volume of chondrocytes mass was augmented after 8 weeks' incubation. The species demonstrated semitransparence and rigidity of normal cartilage. The chondrocytes laid in lacuna surrounding by cartilage-like matrix histologically, and collagen II expressed positively. The analysis of GAG indicated that the chondrocytes maintained the ability of proliferation and excreted the ECM to form the construction of cartilage. Conclusion: This study indicates that the chondrocytes mass simulate the three-dimensional environment which is integrant for the tissue-engineered cartilage, and it is an effective method for the-5-fabrication of neocartilage.Experiment 2: Effects of bFGF on the ECM synthesization and cells proliferation of chondrocytes in vitro.[Abstract] Objective: Effects of basic fibroblast growth factor were investigated on the cells proliferation and synthesized extracellular matrix of cultured chondrocytes. Methods: Isolated chondrocytes from rabbit auricular cartilage by enzyme digestion were encapsulated in alginate at a density of 107cells/ml. The alginate beads of chondrocytes were prepared by dropping the cells/alginate into 102mM CaCl2 solution through a 22 gauge needle and were allowed to polymerized for 10 min. The beads were cultured for 14 days with DMEM added with Ong/ml, l0ng/ml, 50ng/ml and l0ng/ml bFGF and were ceased for biochemical analysis. Results: 14 days later, each bead contained an average of 3.4#g, 4.7#g, 6.6#g, 6.8#g DNA, and the amount of GAG was 15.4#g, 20.6#g, 29.7#g, 31.lug, and the amount of GAG per micrograms was 4.47, 4.39, 4.50, 4.55#g/#g. Conclusion: It demonstrates that bFGF has a distinct effect on the proliferation and the total amount of GAG of chondrocytes in vitro, and bFGF may play an important role on the fabrication of neocartilage.Experiment 3: The effect of basic fibroblast growth factor on the formation of tissue-engineered cartilage in vivo.[Abstract] Objective: The effects of basic fibroblast growth factor were investigated on the formation of cartilage. Methods: Chondrocytes isolated by enzyme digestion from rabbits' auricular cartilage were mixed with 1.2% sodium alginate solution, added bFGF with a density of 50ng/ml. The mixture was injected onto the dorsum of nude mice after 102mM CaCb were added for gelation. 3, 6 weeks later, the formation of neocartilage was observed histological by species stained with H&E and alcian blue. The amount of GAG was analyzed biochemically. Results: 6 weeks after implantation, mature neocartilage were observed in the composites with FGF, and the amount of GAG was significantly increased, hi contrast, the neocartilage were still immature in the control. Conclusion: This study indicates that the bFGF has a beneficial effect on the formation of tissue-engineered neo...
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