Faculty of Science and Technology, Department of Intelligent Machines and System Engineering, Hirosaki University, Japan.
Faculty of Agriculture and Life Science, Department of Biochemistry and Molecular Biology, Hirosaki University, 3 Bunkyo-cho, Hirosaki 036-8561, Japan.
Ultrasonics. 2014 Aug;54(6):1430-8. doi: 10.1016/j.ultras.2014.04.026. Epub 2014 May 8.
The rat lung epithelial cell line SV40-T2 was used to develop a cellular biosensing system to assay for environmental toxicants. The novel approach on which this system is based involves direct attachment of cultured rat or human cells onto a cell-adhesive matrix on the device through which shear horizontal surface acoustic waves (SH-SAW) are transmitted using 50 MHz SAW resonator. This novel design enables sensitive monitoring of changes of the electrophysical characteristics of cells, such as their conductivity and relative permittivity. A time-dependent change of phase of SAW and change of insertion loss (change of amplitude) were observed when the cells were treated with 0.5 or 1.0 mM H2O2. The change of insertion loss was biphasic, with an early phase (1-3 h) and a late phase (3-6 h). The late phase coincided with the destruction of cell-cell tight junctions detected by measurement of the transepithelial electrical resistance and paracellular permeability; in contrast, the early phase coincided with the destruction of intracellular actin filaments by H2O2. The early-phase effect of H2O2 on phase shift may be attributable to the change of intracellular permittivity by a change of cellular polarity. Immunofluorescence microscopy showed the disappearance of zonula occludens protein 1 from the region of cell-cell contact. These results suggest the correlation between the change of insertion loss as an SAW parameter and the destruction of tight junctions of the cells on the SH-SAW device in the late phase.
SV40-T2 大鼠肺上皮细胞系被用于开发细胞生物传感系统，以检测环境毒物。该系统所基于的新颖方法涉及通过将培养的大鼠或人类细胞直接附着到设备上的细胞粘附基质上，通过该基质传输 50MHz 的切向水平表面声波 (SH-SAW)。这种新颖的设计能够敏感地监测细胞电物理特性的变化，例如它们的电导率和相对介电常数。当用 0.5 或 1.0mM H2O2 处理细胞时，观察到 SAW 的相位和插入损耗（幅度变化）的时间依赖性变化。插入损耗的变化呈双相性，具有早期相（1-3 小时）和晚期相（3-6 小时）。晚期相与细胞-细胞紧密连接的破坏同时发生，通过测量跨上皮电阻和旁通透性检测到；相比之下，早期相与 H2O2 破坏细胞内肌动蛋白丝同时发生。H2O2 对相移的早期阶段效应可能归因于细胞极性变化引起的细胞内介电常数的变化。免疫荧光显微镜显示，封闭蛋白 1 从细胞-细胞接触区域消失。这些结果表明，作为 SAW 参数的插入损耗变化与 SH-SAW 设备中细胞紧密连接的破坏之间存在相关性。
