keratinocyte

cell

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June 30, 2026

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Keratinocytes are the primary cells of the epidermis, the outermost layer of the skin. These cells are formed in the basal layer of the epidermis and migrate outward, undergoing significant changes as they move towards the surface.12

As keratinocytes mature, they fill with a fibrous structural protein called keratin. This process leads to the formation of the stratum corneum, or horny layer, which consists of dead, keratin-filled cells. This layer is crucial for protecting the body from water loss and external chemicals. In addition to keratinocytes, the epidermis also contains melanocytes (for skin color), Merkel cells (sensory structures), and Langerhans cells (involved in immune defense).34521

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melanocyte
…with a group of neighbouring keratinocytes (keratin-synthesizing epidermal cells) into which its dendrites transfer pigment. This structure is known as an epidermal melanocyte unit. The melanin produced by melanocytes is of two kinds: dark brown eumelanin and pale red or yellowish phaeomelanin. Both are formed within the melanocytes by the…
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…with a group of neighbouring keratinocytes (keratin-synthesizing epidermal cells) into which its dendrites transfer pigment. This structure is known as an epidermal melanocyte unit. The melanin produced by melanocytes is of two kinds: dark brown eumelanin and pale red or yellowish phaeomelanin. Both are formed within the melanocytes by the…
Read More

stem cell
Epithelial stem cells
…contains layers of cells called keratinocytes. Only the basal layer, next to the dermis, contains cells that divide. A number of these cells are stem cells, but the majority are transit amplifying cells. The keratinocytes slowly move outward through the epidermis as they mature, and they eventually die and are…
Read More
…contains layers of cells called keratinocytes. Only the basal layer, next to the dermis, contains cells that divide. A number of these cells are stem cells, but the majority are transit amplifying cells. The keratinocytes slowly move outward through the epidermis as they mature, and they eventually die and are…
Read More