[Isolation and identification of neural precursor cells from human embryonic cortical tissue].

OBJECTIVE: To isolate neural precursor cells from human embryonic cortical tissue of 20 weeks and identify their proliferation capacity as well as differentiating potential. METHODS: Human fetuses of about 20 weeks from spontaneous abortion were adopted. A serum-free medium containing basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) was used to make the neural precursor cell divide continuously in the culture. The proliferating ability of these cells was tested with BrdU. Growth factors were removed so as to induce differentiation of the precursor cells. The cell cycle of the cells in the neurosphere was analysed using flow cytometry. RESULTS: Cells from human embryonic cortical tissue could be maintained and propagated in the presence of growth factors. Neurospheres generated continually and the cells in the sphere could incorporate into BrdU. Upon differentiation, the precursor cells gave rise to mature neurons, astrocytes and oligodendrocytes. They retained their multilineage potential over repeated passages. The cell cycle analysis indicated that the cells proliferated actively. CONCLUSION: Cells that able to self-renew and differentiate into mature cells in culture cam be isolated from human embryonic tissues. They are verified to be neural precursor cells.