The junctional zone beneath migrating epidermis*

The changes that take palce in skin explants in vitro at the interface between migrating epidermal cells and dermis have been examined by light and electron microscopy and by immunofluorescent antibody techniques. In the first 24 hr epidermal cell migration occurred in the absence of any of the usual components of this junctional zone. After 48 hr of incubation antigenic determinants of the basal zone were detected and basal lamina was demonstrated ultrastructurally. It is proposed that migrating epidermal cells do not need a complex and specialized junctional zone and that these cells are themselves responsible for the elaboration of new basal lamina.