A Microchamber Device for Evaluation of the Barrier Functions of Epithelial Cells

We developed a microdevice that measures material permeation via epithelial tight junction (TJ) to evaluate its barrier function. This device is equipped with microchambers filled with collagen gel, so that a flat epithelial sheet is formed. Since the microchamber is covered by a cell sheet, the influx and efflux of the substrates are normally restricted. However, when the barrier of TJ is altered by drugs or other means, substrates exist in one side diffuses through the sheet, and the local permeability should be measured by observing the time-variation of the fluorescence intensity of individual chambers. In this study, the mass transfer of fluorescent dextran, a model substrate, was measured in correlation to the morphology of MDCK cells. Finally, the alteration of the paracellular permeation in response to the drug was demonstrated.