Figure 1.

A mouse eccrine sweat gland and cellular constituents are depicted. As labelled, the eccrine gland comprises a secretory coil in the deep dermis and a relatively straight duct open to the skin surface (left panel). The secretory coil contains three types of cells, clear, dark and myoepithelial, all derived from embryonic ectoderm. Clear and dark cells are secretory cells, and myoepithelial cells form a major niche for sweat gland stem/progenitor cells (right lower panel). The sweat duct consists of suprabasal (luminal) and basal layers where ions partially reabsorbed (right upper panel).