[Structural-functional units of epidermis].

The available data suggest that epidermis is organized in discrete structural and functional units (SFUs) reproduced both in vivo and in vitro. SFUs are formed in a culture of epidermal keratinocytes by self-organization of the forming cellular elements. SFUs are capable of self-sustaining and form a niche for the stem cells. At the same time, due to the maintained asymmetric kinetics of the stem cell proliferation, SFUs serve as a barrier for their uncontrolled replication.