目的　从 2 0周人胚皮层中分离神经前体细胞并鉴定其增殖及分化能力。方法　应用包含碱性成纤维细胞生长因子 (bFGF)和表皮细胞生长因子 (EGF)的无血清限制培养基从 2 0周自然流产人胚胎皮层组织中分离神经前体细胞 ,通过神经球形成法使其不断增殖 ,利用BrdU检测细胞的增殖能力 ,去除生长因子后诱导神经前体细胞分化。利用流式细胞仪检测神经球内细胞的增殖细胞周期。结果　人胚胎皮层存在神经前体细胞 ,这些细胞于EGF及bFGF作用下可不断增殖形成神经球 ,并能自我更新和结合BrdU ,于生长因子去除后能够分化成熟的神经元、星形胶质细胞和少突胶质细胞。反复传代后这些细胞可保持其增殖及分化能力。细胞周期结果显示神经球内细胞增殖较为活跃。结论　从人胚胎中分离的细胞能于体外自我更新和分化为成熟的细胞 ,证实为神经前体细胞。 Objective To isolate neural precursor cells from 20-week-old human embryonic cortex and identify their proliferation and differentiation ability. Methods The neural precursor cells were isolated from human spontaneous abortion cortex of 20 weeks by using serum-free medium containing basic fibroblast growth factor (bFGF) and epidermal cell growth factor (EGF). The neural precursor cells Its proliferation, the use of BrdU detection of cell proliferation, removal of growth factors after induction of neural precursor cell differentiation. Detection of proliferating cell cycle in neurospheres by flow cytometry. Results There were neural progenitor cells in human embryonic cortex. These cells could proliferate to form neurospheres under the action of EGF and bFGF, and could self-renew and bind BrdU. After the growth factors were removed, they could differentiate into mature neurons, astrocytes And oligodendrocytes. After repeated passage of these cells can maintain their proliferation and differentiation. Cell cycle results show that neurospheres are more active cell proliferation. Conclusion The cells isolated from human embryos can self-renew and differentiate into mature cells in vitro, which is confirmed as neural progenitor cells.