Immunologic, functional, and morphological characterization of three new human small intestinal epithelial cell lines

Background & Aims: Epithelial cell cultures can be used for the study of epithelial cell biology, although human small intestinal cultures have not been available to date. The aim of this study was to characterize three cell lines derived from normal human duodenum. Methods: Cells were cultured from tissue fragments obtained from endoscopic biopsy specimens and characterized with respect to morphology and cytokine gene expression acid for the presence of vectorial transport. Results: All cell lines grew as polarized continuous monolayers and were mostly cuboidal in shape but were not immortalized. Cells showed junctional complexes and sparse microvilli. Ail cell lines showed cytokeratins and mucin antigen but not chromagranin and messenger RNA for epidermal growth factor, interleukin 6, and vascular cell adhesion molecule 1. Disaccharidase activities were low and correlated with the low proportion of cells (1%-10%), showing positive immunocytochemistry for sucrase. Monolayer resistance varied from 30 to 200 Omega. One monolayer (BN) consistently showed secretion in response to forskolin (10 mu mol/L), which could be inhibited by chloride-free buffer and apical addition of the chloride channel blocker diphenylamine decarboxylate. No monolayer had evidence of glucose transport. Conclusions: These three nonimmortalized lines show morphological, phenotypic, and transport characteristics of crypt-like intestinal epithelial cells. The pattern of messenger RNA expression suggests a growth-promoting and immunomodulatory role.