Skin: Stem and Progenitor Cells in Adults

The skin is the outermost layer of the human body and is vital in protecting the body from the daily wear and tear that results from the external environment. The sustainability of the skin as a protective barrier relies on its inherent ability to continuously restore itself as it is damaged. The skin is able to replenish and maintain its cell population over the lifetime of an adult through tissue homeostasis. Skin homeostasis is dependent on different populations of adult stem cells that provide the reservoir of cells necessary to balance cell loss with cell division. Thus, adult stem cells are of particular importance to the skin and its functional role in the human body.