Stratum basale
The stratum basale (basal layer, sometimes referred to as stratum germinativum) is the deepest layer of the five layers of the epidermis, the outer covering of skin in mammals.
The stratum basale is a single layer of columnar or cuboidal cells. The cells are attached to each other and to the overlying stratum spinosum cells by desmosomes and hemidesmosomes. The nucleus is large, ovoid and occupies most of the cell. Some basal cells can act like stem cells with ability to divide and produced new cells , whereas others serve to anchor the epidermis glabrous skin (hairless), and hyper-proliferative epidermis (from a skin disease).[1]
The stratum basale is primarily made up of basal keratinocyte stem cells, which can be considered the stem cells of the epidermis. They divide to form the keratinocytes of the stratum spinosum, which migrate superficially.[2] Other types of cells found within the stratum basale are melanocytes (pigment-producing cells), Langerhans cells (immune cells), and Merkel cells (touch receptors).
Additional images
- Epidermis and dermis of human skin
- Section of epidermis