目的探索以骨髓间充质干细胞(BMSCs)为种子细胞,在体外构建具有完整内侧半月板形态的软骨样组织的方法。方法运用模具制备内侧半月板形的PGA/PLA支架。抽取犬骨髓,分离培养BMSCs,将其接种于支架材料上,5 d后使用软骨诱导液培养。体外培养6周后,行大体观察、组织学检测及生物力学检测。结果细胞材料复合物能够较好地维持半月板三维立体结构,形成了表面光滑、触之有弹性的瓷白色软骨样组织。HE染色可见典型的软骨陷窝出现,说明成熟软骨组织的形成。Safranine O染色证实有蛋白聚糖基质产生。生物力学检测显示,新生组织弹性模量达正常半月板组织的12.7%。结论 BMSCs通过体外诱导,可在体外分化为较成熟的软骨组织,并构建出组织工程化半月板。

Objective To explore the techniques of constructing tissue engineered meniscus with bone marrow mesenchymal stem cells (BMSCs) in dog model in vitro. Methods Biodegradable scaffolds in shape of meniscus were fabricated with polyglycolic acid (PGA) and polylactic acid (PLA) by mold. BMSCs were harvested from bone marrow of dogs and cultured in vitro. Then the expanded cells were seeded onto the scaffolds, and transferred to chondrogenic medium after 5 days. Gross observation, histological observation and biomechanical test were carried out after cultured for 6 weeks. Results The constructs cultured in vitro for 6 weeks maintained three-dimensional structure of meniscus approximately, and formed smooth white cartilage-like tissue with elasticity. HE staining showed typical mature lacuna, suggesting the formation of mature cartilage tissue. Safranin'O staining showed abundant proteoglycan. Biomechanical analyses indicated that Young's modulus of constructs can reach 13.2% of native meniscus. Conclusion BMSCs can differentiate into heterogeneous cartilage-like tissue successfully through cultivation of inducing system, and construct tissue engineered meniscus in vitro.