Fine structure of dendritic cells in the epithelial cell layer of the ox tongue
It is known that some kinds of dendritic cells are distributed in the epithelial cell layer of mucous membrane consisting of stratified squamous epithelium. In the process of exfoliation of the epithelial layer from the underlying connective tissue, dendritic cell bodies exposed on the ruptured surface of the epithelium were detected by scanning electron microscopy. These cells were also observed by light microscopy as well as by transmission electron microscopy.Dorsal mucous membrane of the ox tongue was fixed in Karnovsky's fixative or in 10% formalin. For scanning electron microscopy samples were immersed in 3N-HCl solution for 2-3 weeks at room temperature. The epithelial cell layer was removed from the underlying connective tissue layer1). They were postfixed in tannic acid and then 1% OsO4 for 1 hr. After dehydration in an ethanol series, the specimens were dried by passing through t-butylalcohol, coated with platinum-palladium and observed under an S-800 scanning electron microscope. For transmission electron microscopy, small pieces of the fixed tissue were post-fixed in 1% OsO4 for 1.5 hr and then embedded in Araldite-Epon.