Discontinuous dielectrophoresis a technique for investigating the response of loosely adherent cells to high shear stress

The functioning of cells under mechanical stress influences several cellular processes, for example proliferation, organogenesis, and transcription. Current techniques used to examine mechanical stress on loosely adherent cells, are however, primarily focused on single individual cells being stimulated, or require time-consuming surface coating techniques; and are limited in the level of shear stress that can be supplied to immobilised cells. Here we report the process of the technique, discontinuous dielectrophoresis; which enables high shear stress analysis of clusters of immobilised loosely adherent cells, we have analysed the performance of the system using Saccharomyces cerevisiae yeast cells, up to a shear stress of 42 dyn/cm2. Additionally, we provide application experimental results from investigating shear induced calcium signalling of HEK-293-TRPV4 cells at flow rates of 2.5, and 120 μl/min, corresponding to shear stress levels of 0.875 and 42 dyn/cm2, respectively. In summary, discontinuous dielectrophoresis will enable the investigation of the mechanotransduction behaviour of loosely adherent cells under physiologically relevant shear stresses. Additionally, discontinuous dielectrophoresis provides the capability for parallelism, and dynamic control over the microenvironment, as previously explored by different microfluidic platforms without the capacity for high shear stress analysis of loosely adherent cells.