A new method to culture primary neural stem cells of embryonic rats / 中国组织工程研究

ABSTRACT

BACKGROUND:Both in vivo and vitro microenvironment can influence the proliferation and differentiation of neural stem cells (NSCs). In addition, cell culture solution plays variable roles in cell proliferation and differentiation.OBJECTIVE:To develop a convenient and rapid method to promote NSC primary culture by modifying traditional serum-free medium. DESIGN, TIME AND SETTING:Randomized controlled cell trial was performed at Institute of Brain Science, Qingdao University Medical School from November 2005 to September 2006.MATERIALS:Ten Wistar rat of gestation for 12-16 days; cell suspension fron brain tissue of embryonic rat. METHODS:Cell suspension were seeded into four 50-mL culture flasks with cell density of 1×106 mL-1, and divided into 2 groups with 2 flasks in each group. The control cells (flasks A and B) were cultured in serum-free medium containing DMEM/F12, B27 (2%), basic fibroblast growth factor (20 μg/L), and epidermal growth factor (20μg/L), and the experimental cells (flasks C and D) were firstly cultured with DMEM/F12 containing fetal bovine serum (FBS, 5%), following by the same serum-free medium 2 to 3 days later. MAIN OUTCOME MEASURES:The proliferation of NSCs was observed by inverted microscopy and immunocytochemistry.RESULTS:①Most of the cells in two culture conditions expressed nestin, the specific marker of NSCs, and were immunocytochemically positive. ②Neural stem cells cultured with FBS formed neurospheres 3-4 days earlier than those without FBS. ③There were no significant differences in cell number, but the neurospheres under the experimental condition were larger than those in control group. Some of the cells were neurone specific enolase-positive after serum-conditioned induction, and some were glial fibrillary acidic protein-positive, indicating NSCs had differentiated into neuron-like cells and neurogliocytes.CONCLUSION:FBS-conditioned pre-culture can accelerate the proliferation of neural stem cells.