Nakajima Masafumi, Ishimuro Toshinari, Kato Koichi, Ko In-Kap, Hirata Isao, Arima Yusuke, Iwata Hiroo
Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
Biomaterials. 2007 Feb;28(6):1048-60. doi: 10.1016/j.biomaterials.2006.10.004. Epub 2006 Nov 1.
Neural stem cell (NSC) has emerged as a potential source for cell replacement therapy following traumatic injuries and degenerative diseases of the central nervous system. However, clinical applications of NSC further require technological advances especially for controlling differentiation of NSC. This study aimed at developing biomaterials that serve to expand undifferentiated NSC or to induce cells with specific phenotypes. Our approach is to construct composite biomaterials that consist of extracellular matrix components and growth factors. In order to optimize matrix-growth factor combinations, we conducted the parallel and rapid screening of composite biomaterials through assays using cell-based arrays. The photo-assisted patterning of an alkanethiol self-assembled monolayer was employed to achieve site-addressable combinatorial immobilization of natural and synthetic matrices incorporated with growth factors including epidermal growth factor (EGF), ciliary neurotrophic factor (CNTF), nerve growth factor (NGF), and neurotrophin-3 (NT-3). NSC obtained from the rat embryonic striatum was cultured directly on the array to screen for cell adhesion, proliferation, and promotion of neuronal and glial specification. The results showed that the significant number of cells adhered to laminin-1, fibronectin, ProNectin, and poly(ethyleneimine). It was found that cells proliferated most extensively on a spot with immobilized EGF among the spots with different matrix-growth factor combinations. The results also showed that neuronal differentiation was promoted on the spots with immobilized NGF or NT-3, and astroglial differentiation with CNTF. Importantly, observed effects of growth factors were frequently altered depending on the type of co-immobilized matrices, suggesting synergic effects of adhesion and growth factor signals.
神经干细胞（NSC）已成为创伤性损伤和中枢神经系统退行性疾病后细胞替代治疗的潜在细胞来源。然而，NSC的临床应用还需要技术进步，特别是在控制NSC分化方面。本研究旨在开发用于扩增未分化NSC或诱导具有特定表型细胞的生物材料。我们的方法是构建由细胞外基质成分和生长因子组成的复合生物材料。为了优化基质 - 生长因子组合，我们通过基于细胞阵列的测定对复合生物材料进行了平行快速筛选。采用烷硫醇自组装单层的光辅助图案化技术，实现了包含表皮生长因子（EGF）、睫状神经营养因子（CNTF）、神经生长因子（NGF）和神经营养素 - 3（NT - 3）等生长因子的天然和合成基质的位点可寻址组合固定化。将从大鼠胚胎纹状体获得的NSC直接培养在阵列上，以筛选细胞粘附、增殖以及神经元和神经胶质细胞特异性的促进情况。结果表明，大量细胞粘附于层粘连蛋白 - 1、纤连蛋白、ProNectin和聚乙烯亚胺。发现在不同基质 - 生长因子组合的斑点中，细胞在固定有EGF的斑点上增殖最为广泛。结果还表明，在固定有NGF或NT - 3的斑点上促进了神经元分化，而在固定有CNTF的斑点上促进了星形胶质细胞分化。重要的是，观察到的生长因子效应经常因共固定化基质的类型而改变，这表明粘附和生长因子信号具有协同作用。
