Keratiniserat

Keratiniserat is a term used to describe keratinized epithelium, where the surface cells have become filled with keratin and typically lose their nuclei, forming a tough, protective layer. The word is used in Swedish as keratiniserat and corresponds to the English term keratinized.

In the skin, keratinization is part of a controlled differentiation of keratinocytes. Cells originate in the basal layer, migrate through the spinous and granular layers, and eventually reach the outermost layer as corneocytes. These dead, keratin-rich cells are enveloped by a cornified envelope and held together by lipids, contributing to the barrier function of the epidermis and to desquamation (shedding) of the surface.

Keratinized epithelium also occurs in certain mucosal regions. For example, the hard palate and the gingiva are keratinized, whereas other mucosal surfaces such as the lining of the cheek (buccal mucosa) are non-keratinized. This distinction helps define tissue type and function in health and disease.

Histologically, keratinization can vary. Orthokeratosis refers to a keratinized layer without nuclei, while parakeratosis describes a keratinized layer in which nuclei persist. Hyperkeratosis denotes a thickened keratin layer. These patterns are used in diagnosing dermatological and oral lesions and can indicate normal variation or pathology.

In summary, keratiniserat denotes keratinized epithelium, a key feature of protective skin layers and select mucosal areas, with well-defined cellular changes from basal keratinocytes to surface corneocytes.