Microfluidic Shear Devices for Quantitative Analysis of Cell Adhesion

TLDR

We developed microfluidic devices that enable quantitative assessment of cell adhesion to fibronectin‑coated substrates under controlled shear stress and biochemical conditions, supporting long‑term culture and reagent delivery. The devices vary shear force and surface chemistry by manipulating geometry and coatings, and capture detachment dynamics with time‑lapse videomicroscopy while permitting perfusion for sustained viability. The platform offers a wide range of shear forces, high‑throughput performance, and integration capability, and demonstrates that fibroblasts reduce adhesion strength to fibronectin when stimulated with epidermal growth factor.

Abstract

We describe the design, construction, and characterization of microfluidic devices for studying cell adhesion and cell mechanics. The method offers multiple advantages over previous approaches, including a wide range of distractive forces, high-throughput performance, simplicity in experimental setup and control, and potential for integration with other microanalytic modules. By manipulating the geometry and surface chemistry of the microdevices, we are able to vary the shear force and the biochemistry during an experiment. The dynamics of cell detachment under different conditions can be captured simultaneously using time-lapse videomicroscopy. We demonstrate assessment of cell adhesion to fibronectin-coated substrates as a function of the shear stress or fibronectin concentration in microchannels. Furthermore, a combined perfusion-shear device is designed to maintain cell viability for long-term culture as well as to introduce exogenous reagents for biochemical studies of cell adhesion regulation. In agreement with established literature, we show that fibroblasts cultured in the combined device reduced their adhesion strength to the substrate in response to epidermal growth factor stimulation.