聚乳酸/聚羟基乙酸共聚物修复髌股关节软骨缺损

摘要 背景：传统的方法修复软骨损伤，易发生退变。聚乳酸/聚羟基乙酸共聚物具有良好的生物相容性，可根据需要调节降解速度等性能，可能在修复软骨损伤方面具有应用前景。 目的：观察以聚乳酸/聚羟基乙酸共聚物为载体修复兔关节软骨缺损的可行性。 方法：选取2月龄新西兰兔骨髓培养，诱导间充质干细胞向软骨细胞分化。第3代细胞与聚乳酸/聚羟基乙酸共聚物共培养制成聚乳酸/聚羟基乙酸共聚物-细胞复合物。建立兔髌股关节股骨髁部缺损模型，在右侧36个膝关节植入聚乳酸/聚羟基乙酸共聚物-细胞复合物，左侧18膝植入聚乳酸/聚羟基乙酸共聚物，另18膝造成缺损后留作空白对照。术后4，8，12，24，36，48周取材，行大体及组织学观察，组织学评分。 结果与结论：聚乳酸/聚羟基乙酸共聚物-细胞复合物修复大鼠缺损后，软骨细胞分布较均一，色泽与正常软骨相似，与正常软骨界限消失，表面细胞平行于关节面，深层细胞排列紊乱，细胞呈团状，基质异染广泛，软骨下骨形成及潮线恢复正常，与周围正常软骨连接良好。而单纯植入聚乳酸/聚羟基乙酸共聚物或缺损后未处理大鼠缺损边缘细胞呈团块状增生，底部为纤维组织。提示骨髓基质细胞源性软骨细胞是修复关节软骨缺损较理想的种子细胞，聚乳酸/聚羟基乙酸共聚物适合作为组织工程修复关节软骨缺损的支架材料，具有良好的应用前景。 关键词：聚乳酸/羟基乙酸共聚物；髌股关节；组织工程；骨髓基质细胞；载体材料；软骨缺损；分化 doi:10.3969/j.issn.1673-8225.2011.16.007

Repairing articular cartilage defects in rabbits using poly(lactic-co-glycolic acid)

Abstract BACKGROUND: Traditional methods to repair cartilage damage are prone to induce degeneration. Poly(lactic-co-glycolic acid) (PLGA) has good biocompatibility, its degradation rate can be adjusted according to the requirements, has a potential application prospect in the repair of cartilage damage. OBJECTIVE: To study the feasibility of repairing articular cartilage defect in rabbits using PLGA as a carrier. METHODS: Two-month-old New Zealand white rabbits were selected, and the marrow stromal cells were induced into chondroncytes. The third passage of cells and the PLGA were co-cultured for 24 hours, then PLGA-cell composites were prepared ready. Defects were made in femoral condyles of rabbit patellofemoral joint, and the right 36 knees were treated with PLGA-cell composites, the left 18 knees was implanted with PLGA only, the other 18 knees were left untreated as control group. At 4, 8, 12, 24, 36, 48 weeks after operation, the animals were killed and the newly formed tissues were observed grossly and graded histologically. RESULTS AND CONCLUSION: After the defects in rabbits were repaired using PLGA-cell composite, the chondrocytes distributed uniformly, the color and the luster of the defects were similar to that of the normal cartilage, and was ill-demarcated from the surrounding normal cartilage. The cells on the surface paralleled to joint surface, and the cells in the deep layer arranged disorderly. The cells clustered together, the matrix was extensively metachromatic. The subchondral bone formed, the tide mark basically recovered, and the new cartilage integrated with normal cartilage finely. As for only PLGA group and untreated group, chondrocytes proliferated in the border, but on the bottom, there were mainly fibrous tissues. Chondroncytes derived from marrow stromal cell are ideal seed cells for repairing articular cartilage defect. PLGA can be used as a suitable matrix material for the repair of cartilage defect and may have a good prospect for clinical use.