Effect of cell passage on differentiation of bone marrow mesenchymal stem cells into neural stem cells / 中国组织工程研究

ABSTRACT

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