[The role of the basal cell layer in the maintenance of normal corneal epithelium].

A method of desquamating single layers of corneal epithelial cells through the use of digitonin allowed the observation of the basal cell layer by scanning electron microscope. Basal cells of normal rabbit corneal epithelium were observed as small, round, and columnar-shaped cells, and the mean cell areas of superficial and basal cell layers were 507. 3 +/- 46.6 microns 2, and 39.5 +/- 2.8 microns 2, respectively. The mitotic rate of basal cells was also evaluated immunohistochemically using anti-PCNA (proliferating cell nuclear antigen) monoclonal antibody and the flat preparations of corneal epithelium. The mitotic rate (PCNA positive cells in the basal cell layer) was approximately 4%, and showed no difference between the center and peripheral portion of the cornea. We think these two new methods are useful for the analysis of morphological and functional characteristics of corneal epithelial basal cells.