A device for sterile measurement of transepithelial electrical parameters of cultured cells

Abstract

Cultured epithelial cells grow into organized epithelia and when grown on permeable supports they develop distinctive electrical properties. These electrical properties, which include transepithelial potential difference (PD), resistance, and short circuit current (Isc), may be used to characterize the epithelia in terms of organization, transport, and response to hormones. We have developed a simple device for the repetitive sterile measurement of the transepithelial PD and resistance and Isc of epithelial cells grown in filter-bottom cups. The device is basically a two-part open chamber into which the filter-bottom cup is placed, and the electrical seal between apical and basolateral surfaces is formed by the sides of the filter-bottom cup. The chamber is maintained sterile so that repeat measurements may be made in a laminar flow hood over extended periods of time without risk of infection. Measurements of transepithelial PD, resistance, and Isc of A-6 cells or TB6C cells made with this device are not different from the same measures made in a more conventional Ussing-type chamber (which was used to establish the relation between Isc and isotopically measured net Na+ flux). Measurements of potential difference are identical to those of a commercially available device, and resistance measurements are similar when appropriate backgrounds are considered. Our device is a simply constructed and easily maintained instrument for monitoring transepithelial electrical characteristics of cultured cells and their responses to hormones or other agents.