Comparison of Torque-Based and Force-Based Models of Collective Cell Motion in DC Electric Fields

We compare two computational models of the motion of a cluster of cells exposed to a DC electric field. The base model in which the electric field produces a net force on a cell linearly proportional to the field has been previously studied. The model introduced in this study assumes the action of the electric field on a cell exerts a torque but the field produces no net force on the cell. This torque drives the cell’s axis of polarization into alignment with the field. We show that the torque and force models both result in the same field-dependent directionality of cell motion. However, both the velocity of the cluster and the average speed of individual cells have distinctively different dependences on electric field strength. In this study cells are represented as 2-dimensional disks with an axis of natural motility which experiences a random walk in the absence of a field. The motion of cells is restricted to a plane. Model parameters were selected to match experimental observations of mammalian cranial neural crest cells (CNCC).