Numerical study on the cell motility interacting with the chemical flow in microchannels

Beneficial to the steady control of flow properties and concentration gradient profiles, quantification of cell chemotaxis based on microfluidic devices could achieve on the scale of a single cell. However, normal experimental studies assumed that the concentration field was not affected by the existing cell or by the impact of the cell motion. The present paper systematically simulated the interactions of the cell translational and rotational movements with its chemical gradient flow by both 2D and 3D models. The influences of the chemical flow Peclet number, cell’s translational velocity, cell’s rotational velocity and direction on the sensed chemical gradient were investigated. Results showed that both the cell’s translational and rotational movements disturbed its surrounding chemical distribution and affect chemotactic speed and direction later on. Rotating cell brings in flow circulation with it, and consequently the sensed chemical gradient dramatically deviates from the original direction. The cell’s two contrary rotational directions lead to contrary results. 2D model with circular cell is practically feasible due to simplicity, while 3D model with spherical cell is closer to reality. Numerical comparison showed that the 2D model can be used to analyze the cell’s chemotactic tendency, but it also amplifies the cell’s perturbation and then separation to its surrounding chemical flow. Finally, a single cell’s interactive chemotaxis in a micro chamber was simulated based on experimental measured chemotactic coefficient. The interactive chemotactic cell kept moving slightly upstream instead of upright crossing the interface. This work may contribute to the development of chemotactic measurement method and precise evaluation on the cell’s chemotactic sensitivity.