Direct application of mechanical stimulation to cell adhesion sites using a novel magnetic-driven micropillar substrate
Direct application of mechanical stimulation to cell adhesion sites using a novel magnetic-driven micropillar substrate
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DOI：
10.1007/s10544-018-0328-y
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发表时间：
2018-09-26
影响因子：
2.8
通讯作者：
Matsumoto，Takeo
中科院分区：
文献类型：
--
作者：
Nagayama，Kazuaki;Inoue，Takuya;Matsumoto，Takeo
细胞改变在其粘附部位产生的牵引力，这些力在调节各种细胞功能中起着重要作用。在这里，我们开发了一种新的磁驱动微柱阵列PDMS基板，可用于机械刺激细胞粘附部位和相关的细胞牵引力的测量。微柱的直径、长度和中心间距分别为3、9和9 μm。将足够量的铁颗粒成功地嵌入微柱中，使得微柱能够响应于外部磁场而弯曲。我们建立了两种方法来向微柱施加磁场（Suresh 2007）。施加0.3 T的均匀磁场使所有柱弯曲约4 μm（Satcher等人，1997年）。在衬底附近产生磁场梯度在柱上产生明确的局部力。微柱的偏转允许通过柱顶部上形成的粘附位点将外力转移到肌动蛋白细胞骨架。采用磁场梯度法，测定了体外培养的血管平滑肌细胞（SMC）在受到局部周期性牵张刺激后，细胞一侧边缘牵拉力的变化。我们发现，平滑肌细胞的反应是完全不同的细胞，并与较大的预张力伸长细胞表现出显着的收缩后拉伸刺激。我们的磁驱动的微柱基板应该是有用的，在调查细胞的机械转导机制。
Cells change the traction forces generated at their adhesion sites, and these forces play essential roles in regulating various cellular functions. Here, we developed a novel magnetic-driven micropillar array PDMS substrate that can be used for the mechanical stimulation to cellular adhesion sites and for the measurement of associated cellular traction forces. The diameter, length, and center-to-center spacing of the micropillars were 3, 9, and 9 μm, respectively. Sufficient quantities of iron particles were successfully embedded into the micropillars, enabling the pillars to bend in response to an external magnetic field. We established two methods to apply magnetic fields to the micropillars (Suresh 2007). Applying a uniform magnetic field of 0.3 T bent all of the pillars by ~4 μm (Satcher et al. 1997). Creating a magnetic field gradient in the vicinity of the substrate generated a well-defined local force on the pillars. Deflection of the micropillars allowed transfer of external forces to the actin cytoskeleton through adhesion sites formed on the pillar top. Using the magnetic field gradient method, we measured the traction force changes in cultured vascular smooth muscle cells (SMCs) after local cyclic stretch stimulation at one edge of the cells. We found that the responses of SMCs were quite different from cell to cell, and elongated cells with larger pre-tension exhibited significant retraction following stretch stimulation. Our magnetic-driven micropillar substrate should be useful in investigating cellular mechanotransduction mechanisms.