Univ Brest, CNRS, Lab-STICC, 6 avenue Le Gorgeu, 29238, Brest Cedex 3, France.
Eur Biophys J. 2021 Jul;50(5):713-720. doi: 10.1007/s00249-021-01504-w. Epub 2021 Feb 4.
Membrane capacitance and transmembrane potential are sensitive to the proximity of neighboring biological cells which eventually induces anisotropic perturbation of the local electric field distribution in a cell assembly and/or a tissue. The development of robust and reliable multiphysics approaches is essential to solve the challenge of analyzing proximity-induced capacitance coupling (CC) between cells. In this study, we ask to what extent this CC is a minor perturbation on the individual cells or whether it can fundamentally affect bio-electromechanical cues. A key component of our continuum electromechanical analysis is the consideration of elastic models of cells under steady state electric field excitation to characterize electrodeformation (ED). Analyzing the difference between the ED force for a pair of cells and its counterpart for a single reference cell allows us to determine a separation distance-orientation angle diagram providing evidence of a separation distance beyond which the electrostatic interactions between a pair of biological cells become inconsequential for the ED. An attenuation-amplification transition of ED force in this diagram suggests that anisotropy induced by the orientation angle of the cell pair relative to the applied electric field direction has a significant influence on ED and CC. We furthermore observe that the shape of this diagram changes when extracellular conductivity is varied. The results obtained are then contrasted with the corresponding diagrams of similar cell configurations under an oscillating electric field excitation below and above the α-dispersion frequency. This investigation may provide new opportunities for further assessment of electromechanical properties of engineered tissues.
细胞膜电容和跨膜电位对邻近生物细胞的接近程度敏感,这最终会导致细胞集合体和/或组织中局部电场分布的各向异性扰动。开发稳健可靠的多物理场方法对于解决分析细胞间临近诱导电容耦合(CC)的挑战至关重要。在这项研究中,我们想知道这种 CC 对单个细胞的影响是微小的还是它可以从根本上影响生物机电信号。我们连续体机电分析的一个关键组成部分是考虑在稳态电场激励下的细胞弹性模型来表征电极变形(ED)。分析一对细胞的 ED 力与其单个参考细胞的 ED 力之间的差异,使我们能够确定一个分离距离-取向角图,该图证明了一对生物细胞之间的静电相互作用在分离距离之外变得无关紧要,无法引起 ED。在该图中,ED 力表现出衰减-放大转变,这表明细胞对相对于施加电场方向的取向角引起的各向异性对 ED 和 CC 有重大影响。我们还观察到,当改变细胞外电导率时,该图的形状会发生变化。然后将获得的结果与在低于和高于 α 频散频率的振荡电场激励下类似细胞构型的相应图进行对比。这项研究可能为进一步评估工程组织的机电特性提供新的机会。