Abstract:
Electric cell-substrate impedance sensing has been used to measure transepithelial and transendothelial impedances of cultured cell layers and extract cell parameters such as junctional resistance, cell-substrate separation, and membrane capacitance. Previously, a three-path cell-electrode model comprising two transcellular pathways and one paracellular pathway was developed for the impedance analysis of MDCK cells. By ignoring the resistances of the lateral intercellular spaces, we develop a simplified three-path model for the impedance analysis of epithelial cells and solve the model equations in a closed form. The calculated impedance values obtained from this simplified cell-electrode model at frequencies ranging from 31.25 Hz to 100 kHz agree well with the experimental data obtained from MDCK and OVCA429 cells. We also describe how the change in each model-fitting parameter influences the electrical impedance spectra of MDCK cell layers. By assuming that the junctional resistance is much smaller than the specific impedance through the lateral cell membrane, the simplified three-path model reduces to a two-path model, which can be used for the impedance analysis of endothelial cells and other disk-shaped cells with low junctional resistances. The measured impedance spectra of HUVEC and HaCaT cell monolayers nearly coincide with the impedance data calculated from the two-path model.
摘要:
细胞基质阻抗传感已用于测量培养细胞层的跨上皮和跨内皮阻抗,并提取细胞参数,例如交界电阻,细胞-底物分离,和膜电容。以前,建立了包含两条跨细胞通路和一条旁细胞通路的三路细胞电极模型,用于MDCK细胞的阻抗分析.通过忽略横向细胞间隙的阻力,我们开发了一个简化的三路径模型,用于上皮细胞的阻抗分析,并以封闭形式求解模型方程。在31.25Hz至100kHz的频率范围内,从该简化的电池电极模型获得的计算阻抗值与从MDCK和OVCA429电池获得的实验数据非常吻合。我们还描述了每个模型拟合参数的变化如何影响MDCK电池层的电阻抗谱。通过假设连接电阻远小于通过横向细胞膜的比阻抗,简化的三路径模型简化为两路径模型,可用于内皮细胞和其他低连接电阻的圆盘形细胞的阻抗分析。测量的HUVEC和HaCaT细胞单层的阻抗谱与从两路模型计算的阻抗数据几乎一致。