兔骨髓间质干细胞用于构建组织工程软骨组织的初步报告

目的 采用组织工程方法，以培养后的兔骨髓间质干细胞（MSC）制成人工软骨培养物，经体内外培养后发育出成活的软骨组织。方法 抽取兔人经密度梯度离心得到单个核细胞，再经体外分离、培养获得兔骨髓MSC。向MSC培养液内加入地塞米松、转化生长因子－β1（TGF－β1）和维生素C进行软骨起源诱导培养3周，部分细胞开始转变为圆形并分泌基质。将诱导后的细胞与牛Ⅰ型胶原及人纤维蛋白按一定的比例混合，制成软骨样的培养物并分别做体内外培养。结果 体外培养2周后，培养物内大部分细胞已萎缩消失。但剩余的少量细胞成活，形成类似的软骨陷窝并分泌甲苯胺蓝异染的软骨基质。体内移植培养3周后，培养物已发育成颗粒状成熟的软骨组织。结论 骨髓间质干细胞可用于组织工程软骨组织的构建，是一种非常有前途的人工软骨组织构建中的功能细胞。

THE PRIMARY STUDY ON RABBIT BONE MARROW MESENCHYMAL STEM CELLS IN CONSTRUCTING TISSUE-ENGINEERED CARTILAGE

OBJECTIVE: To study the feasibility of constructing tissue engineered cartilage by differentiated rabbit bone marrow mesenchymal stem cells(MSC) cultured in vitro and in vivo. METHODS: The MSC were isolated from the nucleated cells fraction of autologous bone marrow by density gradient centrifuge, and then induced into chondrogenic differentiation by adding dexamethasone, transforming growth factor-beta 1 (TGF-beta 1) and ascorbic acid in vitro. After 3 weeks, some cells turned to round shape and secreted metachromatic matrix. The cartilaginoid grafts composed of chondrogenic MSC. Bovine type I collagen and human fibrin were cultured within the chondrogenic medium for 2 weeks in vitro or transplanted subcutaneously adjacent to the knee joint for 3 weeks in vivo. RESULTS: The most cells in the grafts were degenerated and disappeared after cultured in vitro. But the residual cells were survival and secreted metachromatic staining proteoglycan with toluidine blue, which was characteristic cartilage matrix. The grafts developed into matured cartilage tissue assessed by histological examination after 3 weeks of transplantation in vivo. CONCLUSION: MSC can be used as functional cells to constructing tissue engineered cartilage.