单晶硅材料微型圆柱体直径及其排列间距对神经干细胞分化的影响

摘要

背景：研究表明，不同结构类型的矩阵模型(例如条纹、空洞及圆柱体等)对神经干细胞分化有不同的影响。目的：探讨微型圆柱体直径及其排列间距等物理信号对神经干细胞分化的影响。方法：采用光刻法在单晶硅表面刻蚀出不同直径和间距的微型圆柱体(直径与间距各有2.5，5，10，20µm 4个规格)，将纯化的原代神经干细胞种植在16种微型圆柱体上，体外培养7 d后，运用免疫荧光及实时定量PCR等技术观察神经干细胞分化为神经元样细胞的情况。结果与结论：①在直径固定的情况下：微型圆柱体间距在2.5-10μm范围内变化时，随着间距的增大，神经干细胞分化率有增大的趋势；②在间距固定的情况下：微型圆柱体直径在2.5-20μm范围内变化时，随着圆柱体直径的增大，神经干细胞的分化率越来越小；③对比各组发现，直径为2.5μm、间距为10μm的微型圆柱体对于神经干细胞分化为神经元样细胞的促进作用最明显；④结果表明：在特定规格的微型圆柱体(圆柱体直径较小并其间距较大)上培养神经干细胞能促进其分化为神经元样细胞，这对于研发组织工程支架材料有着重要的提示作用。%BACKGROUND:Different structures of matrix models, such as grating, holes and pil ars make different effects on the differentiation of neural stem cel s. OBJECTIVE:To explore the effects of the diameter and spacing, known as physical signals of micro pil ars on neural stem cel differentiation. METHODS:Micro pil ars with different diameters and spacing, both of which had four dimensions of 2.5, 5, 10 and 20μm, were fabricated on silicon substrates by photolithographic method. Purified primary neural stem cel s were incubated on the each micro pil ar for 7 days in vitro. Then the differentiation of neural stem cel s into neuron-like cel s was observed using immunofluorescence staining and quantitative real-time PCR. RESULTS AND CONCLUSION:When the diameters of the micro pil ars were constant and the spacing of micro pil ars varied in the range of 2.5-10μm, the differentiation rate of neural stem cel s increased with the spacing increase. When the spacing was invariable and the diameters changed in the range of 2.5-20μm, the differentiation rate of neural stem cel s declined with the diameter increase. Especial y, the micro pil ars with 2.5μm diameter and 10μm spacing significantly promoted the differentiation of neural stem cel s into neuron-like cel s. These results show that specific micro pil ars with smal diameters and large spacing facilitate the differentiation of neural stem cel s, thus providing guidance for developing tissue-engineered scaffolds.