Hug T S, Prenosil J E, Morbidelli M
Department of Chemical Engineering, Swiss Federal Institute of Technology, CH-8092 Zurich, Switzerland.
Biosens Bioelectron. 2001 Dec;16(9-12):865-74. doi: 10.1016/s0956-5663(01)00204-4.
Optical Waveguide Lightmode Spectroscopy (OWLS) is based on measurements of the effective refractive index of a thin layer above the waveguide. Its potential as a whole-cell biosensor was demonstrated recently monitoring adhesion and spreading of Baby Hamster Kidney (BHK) cells on-line. In this work the OWLS is shown to be a promising tool to study the adhesion, morphology and metabolic state of fibroblasts in real time. A new design of the measuring chamber allowed simultaneous observation by phase-contrast microscopy and made the adsorbed cell density controllable and reproducible. The OWLS signal correlated quantitatively with the contact-area between the fibroblasts and the waveguide. The OWLS signals for adhesion and spreading of three different fibroblast cell lines were in good agreement with their morphology identified by phase-contrast microscopy. The cell adhesion and cell shape changes were examined in three scenarios: (a) serum-induced spreading of the surface attached fibroblasts was followed until it was completed, and the OWLS signal remained constant for over 12 h; (b) the fully spread cells were exposed to the microtubuli-disrupting colchicine and a decrease of the OWLS signal was monitored; (c) in a similar experiment with benzalkonium chloride, a strong skin irritant, a concentration-dependent response of the signal was found. The results show the strength of the OWLS method for monitoring the adhesion behavior of anchorage-dependent cells such as fibroblasts. It has a great potential as a whole-cell biosensor for high throughput screening in toxicology.
光波导光模式光谱技术（OWLS）基于对波导上方薄层有效折射率的测量。最近通过在线监测幼仓鼠肾（BHK）细胞的黏附与铺展，证明了其作为全细胞生物传感器的潜力。在这项工作中，OWLS被证明是实时研究成纤维细胞黏附、形态和代谢状态的一种有前景的工具。测量腔的新设计允许通过相差显微镜进行同步观察，并使吸附的细胞密度可控且可重复。OWLS信号与成纤维细胞和波导之间的接触面积定量相关。三种不同成纤维细胞系黏附与铺展的OWLS信号与其通过相差显微镜鉴定的形态高度一致。在三种情况下检测了细胞黏附及细胞形状变化：（a）追踪血清诱导的表面附着成纤维细胞的铺展直至完成，OWLS信号在超过12小时内保持恒定；（b）将完全铺展的细胞暴露于破坏微管的秋水仙碱中，并监测OWLS信号的降低；（c）在与强皮肤刺激剂苯扎氯铵的类似实验中，发现信号呈浓度依赖性响应。结果表明OWLS方法在监测如成纤维细胞等锚定依赖性细胞黏附行为方面的优势。它作为毒理学高通量筛选的全细胞生物传感器具有巨大潜力。
