Microfluidics for mammalian cell chemotaxis.

The emerging field of micro-technology has opened up new possibilities for exploring cellular chemotaxis in real space and time, and at single cell resolution. Chemotactic cells sense and move in response to chemical gradients and play important roles in a number of physiological and pathological processes, including development, immune responses, and tumor cell invasions. Due to the size proximity of the microfluidic device to cells, microfluidic chemotaxis devices advance the traditional macro-scale chemotaxis assays in two major directions: one is to build well defined and stable chemical gradients at cellular length scales, and the other is to provide a platform for quantifying cellular responses at both cellular and molecular levels using advanced optical imaging systems. Here, we present a critical review on the designing principles, recent development, and potential capabilities of the microfluidic chemotaxis assay for solving problems that are of importance in the biomedical engineering field.