DERMO‐EPIDERMAL JUNCTION OF NORMAL SKIN

ABSTRACT The dermo‐epidermal junction is a complex structure, composed of semidesmosomes (attachment plaque, cell membrane and junction plate) anchoring filaments, basal lamina, anchoring fibrils and elastic fibrils. A similar structure is seen in other epithelial and endothelial tissues, muscles and nerves. Among them, mucous epithelium is very like the epithelium of skin. As observed under the light microscope, the PAS‐positive basement membrane includes the basal lamina and anchoring fibrils. Elastic fibrils seem to be identical with oxytalan fibers and elastofibrils. Histochemical studies suggest that the junction consists of neutral mucopolysaccharides, collagenous protein, SO4‐groups and lipids. However, no chemical analyses have been done. The normal junction can be separated by physical, chemical or enzymatic methods. Suction is a unique technique for dermo‐epidermal separation. Its formation is studied in embryonic skin, cultivated skin and wound healing. The junction is initiated by an increased density of basal cell membrane and is laid down on the surface of the dermis. The junction binds the epidermis firmly to the corium and controls the passage of material from the dermis to the epidermis or vice versa.