Glycocalyx bending by an electric field increases cell motility

The application of physiological strength electric fields may produce a wide range of effects on cells. The mechanisms by which cells detect the presence of these fields, however, are not fully understood. Previous experiments have shown that directionality of cells in the field is governed by an electromechanical mechanism in which the field exerts a torque on the negatively charged, inner glycocalyx that is then transmitted as a force on the cytoskeleton. This mechanism is similar to that by which cells detect fluid shear forces. Several authors, however, have reported that cell directionality and motility behave differently in an electric field. We propose here a second electromechanical mechanism in which the field bends the negatively charged, outer glycocalyx in proximity to the substrate, increasing cell adhesion and, thus, cell motility. The increase in motility depends not only on the field strength, but also on the adhesion of the cell to the substrate prior to application of the field. We show that these mechanisms are common to both human cells and amoebae and, hence, are evolutionarily conserved. Furthermore, the mechanism for detection of electric fields is simply an extension of the mechanism for detecting fluid shears. Bioelectromagnetics. 38:482-493, 2017. © 2017 Wiley Periodicals, Inc.