甲状腺激素对大鼠骨髓间充质干细胞分化为少突胶质细胞的影响

背景：如何为脱髓鞘疾病的细胞替代治疗提供丰富的少突胶质细胞来源是急需解决的问题。 目的：实验拟采用表皮生长因子及碱性成纤维细胞因子诱导骨髓间充质干细胞向神经干细胞方向分化，撤退细胞因子后，用甲状腺激素诱导神经干细胞向少突胶质细胞分化。 设计、时间及地点：细胞观察实验，于2007-08/12在泸州医学院神经生物学研究室完成。 材料：普通级SD大鼠5只用于骨髓间充质干细胞的培养。 方法：采用密度梯度离心法从大鼠骨髓中分离培养骨髓间充质干细胞，传至第4代，用含碱性成纤维细胞生长因子、表皮生长因子、N2辅助因子、甲状腺激素T3的DMEM/F12诱导液诱导向神经干细胞分化。诱导后4 d，更换成含胎牛血清、甲状腺激素T3的DMEM/F12分化液，诱导向少突胶质细胞分化。 主要观察指标：骨髓间充质干细胞生长情况和形态变化，采用SABC法进行免疫细胞化学检测神经细胞特异性标志的表达。 结果：原代细胞接种3 d后多数贴壁，传代后细胞贴壁速度加快，增殖能力更强。诱导液处理第4天，圆形细胞聚集成簇。换成分化液后，细胞伸出树枝状细长突起，交织成网，形成少突胶质细胞样细胞。骨髓源性细胞簇表达巢蛋白阳性，示神经干细胞；从细胞簇分化的细胞，多数细胞表达半乳糖脑苷脂，部分细胞表达髓鞘碱性蛋白，示少突胶质细胞，少数细胞表达微管相关蛋白2阳性，示神经元。 结论：甲状腺激素在体外可诱导骨髓间充质干细胞向少突胶质细胞分化。

Effects of thyroid hormone on differentiation of rat bone marrow mesenchymal stem cells into oligodendrocytes

BACKGROUND: How to provide rich source of oligodendrocytes of cell alternative treatment for demyelinating disease has been a problem to be solved eagerly. OBJECTIVE: Bone marrow mesenchymal stem cells (BMSCs) of rats were induced differentiation into neural stem cells by epidermal growth factor and basic fibroblast growth factor, and then neural stem cells were induced differentiation to oligodendrocytes by thyroid hormone after retreating growth factor. DESIGN, TIME AND SETTING: The cell experiment was performed at the Department of Neurobiology of Luzhou Medical College from August to December 2007. MATERIALS: Five common Sprague Dawley rats were selected to use for cultivation of BMSCs. METHODS: BMSCs from rats were isolated by combining density gradient centrifugation. The fourth passage of BMSCs were induced differentiation into neural stem cells by DMEM/F12 medium containing epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), N2 factor and thyroid hormone (T3) for 4 days, then in DMEM/F12 supplemented with fetal calf serum and thyroid hormone (T3) induced above cells differentiation into oligodendrocytes. MAIN OUTCOME MEASURES: The growth and the morphological changes of induced BMSCs were observed. Specific markers of neural cells were identified by SABC immunocytochemisty staining. RESULTS: Three days later, most primary cultured cells attached to the bottom. Generated BMSCs rapidly adhered to wall, and proliferated speed of subculture cells was faster than that of primary culture cells. BMSCs were treated by induced liquid for 4 days with round cells, and they assembled into clusters. After changing differentiated liquid, cells extended long dendritic progresses interlaced with one another into a network. Bone marrow-derived cell clusters expressed nestin positive, showing neural stem cells; most of differentiated cells expressed galactocerebroside; partial differentiated cells expressed myelin basic protein, showing oligodendrocytes and a few cells expressed microtubule-associated protein, showing neurons. CONCLUSION: Thyroid hormone can induce bone marrow mesenchymal stem cells differentiation into oligodendrocytes in vitro.