Epithelial cell cultures from the colon of the suckling rat

Epithelial cells from the colon of suckling rats have been propagated in vitro. The colons were excised and cut longitudinally. The epithelial sheets were peeled off and dissociated in 0.1% trypsin solution at 25 degrees C for 10 min. The first cell suspension was discarded and the remaining fragments trypsinized again for an additional 20 min. The dissociated cells were washed and cultured. Forty-eight hours later, several epithelial colonies consisting of closely packed polygonal cells were formed. Transmission and scanning electron microscope examination of the colonies showed numerous regularly spaced microvilli on the surface and tight junctions and desmosomes between adjacent cells. Immunocytochemical studies with antiserum prepared against the brush-border membrane of the colonic epithelium showed specific staining of the epithelial colonies. Epithelial colonies were subcultured by the penicylinder method. Although the subcultured cells retained their epithelial characteristics, the proliferative activity of the cells gradually decreased. Currently, efforts are being made to determine the optimum nutritional requirements of the primary and low-passage cultures.