GROWTH AND PROPAGATION OF NORMAL RAT INTESTINAL EPITHELIAL-CELLS

A combination of mild proteolytic digestion and selective growth stimu lation has been used to isolate and propagate adult rat intestinal epi thelial cells with a finite life span. Growth of these cells on a vari ety of matrices and on mesenchymal cells has resulted in the expressio n of brush border enzymes including sucrase-isomaltase, aminopeptidase N, and alkaline phosphatase. Examination of the cells at the electron microscopic level has revealed that although these cells express key brush border enzymes, they do not have a fully formed brush border. Th ese findings suggest that the expression of brush border enzymes and s tructural proteins represent distinct stages of enterocyte differentia tion that are under separate transcriptional and temporal control.