Kobylkevich Brian M, Sarkar Anyesha, Carlberg Brady R, Huang Ling, Ranjit Suman, Graham David M, Messerli Mark A
Department of Biology and Microbiology, South Dakota State University, Brookings, SD, United States of America. Brian Kobylkevich and Anyesha Sarkar contributed equally to this work.
Phys Biol. 2018 Mar 9;15(3):036005. doi: 10.1088/1478-3975/aaad91.
Weak external electric fields (EFs) polarize cellular structure and direct most migrating cells (galvanotaxis) toward the cathode, making it a useful tool during tissue engineering and for healing epidermal wounds. However, the biophysical mechanisms for sensing weak EFs remain elusive. We have reinvestigated the mechanism of cathode-directed water flow (electro-osmosis) in the boundary layer of cells, by reducing it with neutral, viscous polymers. We report that increasing viscosity with low molecular weight polymers decreases cathodal migration and promotes anodal migration in a concentration dependent manner. In contrast, increased viscosity with high molecular weight polymers does not affect directionality. We explain the contradictory results in terms of porosity and hydraulic permeability between the polymers rather than in terms of bulk viscosity. These results provide the first evidence for controlled reversal of galvanotaxis using viscous agents and position the field closer to identifying the putative electric field receptor, a fundamental, outside-in signaling receptor that controls cellular polarity for different cell types.
弱外部电场（EFs）使细胞结构极化，并引导大多数迁移细胞（趋电运动）朝向阴极，这使其成为组织工程和治疗表皮伤口过程中的一种有用工具。然而，感知弱电场的生物物理机制仍然难以捉摸。我们通过用中性粘性聚合物降低细胞边界层中阴极导向的水流（电渗），重新研究了其机制。我们报告称，低分子量聚合物增加粘度会以浓度依赖的方式降低阴极迁移并促进阳极迁移。相比之下，高分子量聚合物增加粘度不会影响方向性。我们从聚合物之间的孔隙率和水力渗透率而非本体粘度的角度解释了这些矛盾的结果。这些结果首次提供了使用粘性剂控制趋电运动逆转的证据，并使我们更接近于识别假定的电场受体，这是一种基本的外向内信号受体，可控制不同细胞类型的细胞极性。
