细胞传代对骨髓间充质干细胞向神经干细胞分化的影响

Effect of cell passage on differentiation of bone marrow mesenchymal stem cells into neural stem cells

BACKGROUND:It is unclear whether serial cell passage in vitro influences the differentiation of bone marrow mesenchymal stem cells into neural stem cells. OBJECTIVE:To investigate the effect of cell passage on the differentiation of bone marrow mesenchymal stem cells into neural stem cells. METHODS:Rat bone marrow mesenchymal stem cells were isolated and cultured by the whole bone marrow adherence method. Bone marrow mesenchymal stem cells at passages 3, 6, 9, 12 were incubated in serum-free medium. After culture for 7 and 14 days, cell biological characterization was observed and differenitaiton ability into neural stem cells was observed by detecting Nestin expression in cells using flow cytometry. Then, the cells were further induced to differentiate and cell multipotential differentiation capacity was detected by measurement of nerve enolase and glial acidic protein expression. RESULTS AND CONCLUSION:Under induction, bone marrow mesenchymal stem cells at different passages were all differentiated into Nestin-positive neural stem cells. However, there was a significant difference in differentiation proportion of cells at different passages (P < 0.05). Strongest differentiation ability was found in the passage 6 cells, with the Nestin expression up to (93.7±2.3)% at 7 days of induction and (96.2±1.8)% at 14 days of induction. The proportion of differentiated cells at passages 6 and 9 was signfiicantly higher than that at passages 3 and 12. Moreover, adherent cells were positive for nerve enolase and glial acidic protein. All these findings indicate that the differentiation of bone marrow mesenchymal stem cells into neural stem cells is correlated with cell passage. Cells at lower or higher passages are both detrimental to cell differentiation.