Epidermal Stem Cells

• Contrarily to early embryonic (totipotent and pluripotent) stem cells, epidermal stem cells are unipotent. They enable the epidermis to function as a renewal tissue and are thus often called “tissue-specific stem cells”.
• They are located in the Basal Layer of the epidermis along other basal keratinocytes and fewer melanocytes. More precisely they are located close to dermal papillae; these are highly vascularized areas; the structure of a renewal tissue always contains some form of microenvironment – called a “niche” that is favorable for the persistence and function of the stem cells.
• They have the capacity to multiply indefintately.
• They give rise to daughter cells (=progenitor cells) which after multiplying 2 or 3 times differentiate into functional dead corneocytes – ultimately shed = terminal differentiation.
• With aging, there are fewer epidermal stem cells (as well as in the dermis), this results clinically in skin which feels rough when touched (as there are fewer keratinocytes which reach the stratum corneum): Click HERE to read more.

Reference: Slack.J. Stem Cells – A Very Short Introduction. Oxford University Press