Keratinocytes

Keratinocytes are the predominant cell type in the epidermis, the outermost layer of the skin, constituting about 90% of the cells there. They are named for the type of keratin they produce. They are responsible for the formation of the stratum corneum, the outermost layer of the skin, which serves as the body's primary barrier against environmental damage.

Structure and Function

Keratinocytes are derived from the basal cells in the deepest layer of the epidermis. They undergo continuous proliferation and differentiation, moving upwards in the epidermis until they reach the stratum corneum, where they are eventually shed from the surface of the skin. This process is known as keratinization.

Keratinocytes produce a variety of proteins and lipids that contribute to the skin's barrier function. These include keratin, a tough, fibrous protein that provides structural support; and ceramides, a type of lipid that helps to seal the spaces between the cells and prevent water loss.

Role in Disease

Abnormalities in keratinocyte function can lead to a variety of skin diseases. For example, psoriasis is characterized by an overproduction of keratinocytes, leading to thick, scaly patches on the skin. In contrast, eczema is often associated with a deficiency in ceramides, leading to dry, itchy skin.

See Also

• Epidermis (skin)
• Keratin
• Psoriasis
• Eczema

References

Keratinocytes Resources
Latest articles Most recent articles Ongoing trials	Wikipedia