The ability to spatially organise the microenvironment of tissue scaffolds unlocks the potential of many scaffold-based tissue engineering applications. An example application is to aid the regeneration process of peripheral nerve injuries. Herein, we present a promising approach for three-dimensional (3D) micropatterning of nerve cells in tissue scaffolds for peripheral nerve repair. In particular, we demonstrate the 3D micropatterning of PC12 cells in a gelatin-hydroxyphenylpropionic acid (Gtn-HPA) hydrogel using ultrasound standing waves (USWs). PC12 cells were first aligned in 3D along nodal planes by the USWs in Gtn-HPA hydrogel precursor solution. The precursor was then crosslinked using horseradish peroxidase (HRP) and diluted hydrogen peroxide (H2O2), thus immobilising the aligned cells within 90-120 s. This micropatterning process is cost effective and can be replicated easily without the need for complex and expensive specialised equipment. USW-aligned PC12 cells showed no adverse effect in terms of viability or ability to proliferate. To our best knowledge, this is the first report on the effect of USW alignment on neural cell differentiation. Differentiated and USW-aligned PC12 cells showed directional uniformity after 20 d, making this technique a promising alternative approach to guide the nerve regeneration process.

中文翻译：

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使用超声驻波在快速交联的水凝胶支架中对PC12细胞进行快速三维微图案化。

在空间上组织组织支架的微环境的能力释放了许多基于支架的组织工程应用的潜力。一个示例应用是辅助周围神经损伤的再生过程。在本文中，我们提出了一种有希望的方法，用于组织支架中神经细胞的三维（3D）微图案化，以用于周围神经修复。特别是，我们演示了使用超声波驻波（USWs）在明胶-羟苯基丙酸（Gtn-HPA）水凝胶中PC12细胞的3D微图案化。首先通过USW在Gtn-HPA水凝胶前体溶液中沿节点平面将PC12细胞3D对齐。然后使用辣根过氧化物酶（HRP）和稀释的过氧化氢（H2O2）交联前体，从而将对齐的细胞固定在90-120 s之内。这种微图案化工艺具有成本效益，并且可以轻松复制，而无需复杂而昂贵的专用设备。与USW对齐的PC12细胞在生存力或增殖能力方面均未显示不利影响。据我们所知，这是关于USW对齐对神经细胞分化影响的第一份报告。分化的和USW对齐的PC12细胞在20 d后显示方向均匀性，这使该技术成为指导神经再生过程的有前途的替代方法。