Structural characterization of isolated rat epididymal epithelial cells

An enriched suspension of rat epididymal epithelial cells was prepared by sequential enzymatic removal of connective tissue and peritubular cells from the epididymal tubule. The viability, structural characteristics, and pattern of polypeptides synthesized by the isolated cells were determined. Electron microscopic analysis revealed that the isolated principal cells were intact and retained their polarized morphology. Several light microscopic protocols were employed to evaluate the percentage of epithelial cells in the suspensions. These included (1) the visualization of the pattern of FITC-lectin binding in which the principal cells could be identified by their polarized fluorescence; (2) the visualization of prominent autofluorescent granules in the cell cytoplasm which appeared to be characteristic of only epithelial cells; and (3) immunochemical staining with an antikeratin antibody which was reactive only with cells of epithelial origin. These structural probes indicated that between 80% and 90% of the isolated cells were epithelial in nature. Two-dimensional gel electrophoresis revealed a complex pattern of polypeptides synthesized by the epithelial cells; these results are compared to those of earlier studies utilizing minced whole epididymis.