Radotić Viktorija, Braeken Dries, Kovačić Damir
Speech and Hearing Research Laboratory, School of Medicine, University of Split, Šoltanska 2, 21000, Split, Croatia.
Cell and Tissue Technologies Group, Life Science Technologies Department, imec, Kapeldreef 75, 3001, Leuven, Belgium.
Eur Biophys J. 2017 Dec;46(8):719-727. doi: 10.1007/s00249-017-1263-1. Epub 2017 Oct 26.
Many studies have shown that the topography of the substrate on which neurons are cultured can promote neuronal adhesion and guide neurite outgrowth in the same direction as the underlying topography. To investigate this effect, isotropic substrate-complementary metal-oxide-semiconductor (CMOS) chips were used as one example of microelectrode arrays (MEAs) for directing neurite growth of spiral ganglion neurons. Neurons were isolated from 5 to 7-day-old rat pups, cultured 1 day in vitro (DIV) and 4 DIV, and then fixed with 4% paraformaldehyde. For analysis of neurite alignment and orientation, fast Fourier transformation (FFT) was used. Results revealed that on the micro-patterned surface of a CMOS chip, neurons orient their neurites along three directional axes at 30, 90, and 150° and that neurites aligned in straight lines between adjacent pillars and mostly followed a single direction while occasionally branching perpendicularly. We conclude that the CMOS substrate guides neurites towards electrodes by means of their structured pillar organization and can produce electrical stimulation of aligned neurons as well as monitoring their neural activities once neurites are in the vicinity of electrodes. These findings are of particular interest for neural tissue engineering with the ultimate goal of developing a new generation of MEA essential for improved electrical stimulation of auditory neurons.
许多研究表明，培养神经元的底物拓扑结构能够促进神经元黏附，并引导神经突沿与底层拓扑结构相同的方向生长。为了研究这种效应，各向同性的互补金属氧化物半导体（CMOS）芯片被用作微电极阵列（MEA）的一个例子，用于引导螺旋神经节神经元的神经突生长。从5至7日龄的幼鼠中分离出神经元，在体外培养1天（体外培养第1天，DIV）和4天，然后用4%多聚甲醛固定。为了分析神经突的排列和方向，使用了快速傅里叶变换（FFT）。结果显示，在CMOS芯片的微图案表面上，神经元的神经突沿着三个方向轴排列，角度分别为30°、90°和150°，并且神经突在相邻柱体之间呈直线排列，大多沿单一方向，偶尔会垂直分支。我们得出结论，CMOS底物通过其结构化的柱体组织将神经突导向电极，并且一旦神经突靠近电极，就能对排列好的神经元产生电刺激并监测其神经活动。这些发现对于神经组织工程尤为重要，其最终目标是开发新一代对改善听觉神经元电刺激至关重要的MEA。
