RESISTANCE TO ACID OF CANINE KIDNEY (MDCK) AND HUMAN COLONIC (T84) AND ILEO‐CAECAL (HCT–8) ADENO‐CARCINOMA EPITHELIAL CELL MONOLAYERS IN VITRO

Abstract

Monolayers of canine kidney (MDCK) and human lower intestinal (T84 and HCT-8) cell lines generated significant transepithelial electrical resistance (700-5000 .OMEGA. cm2). Electrical integrity was maintained upon acidification of the apical and/or basolateral surfaces to pH 3.0, and this was associated with increased transepithelial electrical resistance, and generation of a potential difference at pH < 4.5. These results indicate that resistance to acid is a general phenomenon of epithelial layers, and that monolayers of epithelial cells, including those of human origin, are a homogeneous and simple model for studying epithelial barrier function in vitro.