脂肪基质干细胞跨胚层分化为神经干细胞的实验研究

Differentiation of adipose-derived stem cells into nerve stem cells across embryonic layer

目的:探讨脂肪基质干细胞向神经干细胞跨胚层分化的可行性,进而为神经系统损伤修复寻找理想的种子细胞.方法:无菌条件下取大鼠腹股沟脂肪组织,消化离心后低糖含血清培养基培养,待细胞生长至亚融合状态改用神经干细胞培养基诱导,用免疫荧光对诱导的细胞进行鉴定.结果:大鼠脂肪基质干细胞在相应培养条件下快速分裂增殖为大而圆并含粗大胞质颗粒的细胞,后者形成细胞球(或称"神经球"),该细胞球表达特殊的神经干细胞Nestin抗原;若进一步将这些细胞球分离成单细胞并重新以克隆密度培养,单个的细胞又很快形成新的神经球.神经干细胞球进一步分化,可见到有的细胞胞体增大并出芽,逐渐发育成为较成熟的长突起细胞,长突起相互连接、交织成网并建立有神经纤维样联系,表达Nse或Gfap抗原.结论:大鼠脂肪基质干细胞在一定条件下可以向神经干细胞跨胚层分化.该种来源的神经干细胞可能成为中枢神经系统损伤修复的理想种子细胞.

AIM： To explore the feasibility of differentiation of adipose-derived stem cells （ADSCs） into neural stem cells （NSCs） , so as to search the perfect source of seed cells to repair the tissue injury of the central nervous system. METHODS： ADSCs, derived from the adipose of rat＇s groin, were induced in NSC-cuhure medium, and then the differentiated cells were identified with immunofluoreseenee. Proliferation of NSCs was evaluated by formation of cell clones. Antibodies against Nestin, NSE and GFAP were used for identifying NSCs, neurons and glial cells, respectively. RESULTS： Among the rat ADSCs, there were many with rough and large cytoplasmic granules, which proliferated rapidly into islets-shaped cellular spheres with positive expression of Nestin, a specific antigen for NSCs. After separating the cellular spheres into single cells and then plating them, we found the islets-shaped cellular spheres formed again. Plated in the DMEM/F12 culture medium which contained 150 mL/L of serum, some of them formed small buds, which then developed further into long projects connecting each other. Most of the cells with long projects showed positive expression of NSE or GFAP. CONCLUSION： It is possible that ADSCs could differentiate into NSCs under certain experimental conditions. ADSCs might be used as the seed-cells of the neural stern cells for repair of the tissue injury of the central nervous system.