keratínfrumur

Keratínfrumur, commonly known as keratinocytes, are the primary cell type in the epidermis, the outermost layer of the skin. They are a type of epithelial cell and are responsible for synthesizing keratin, a tough and fibrous protein that forms the structural basis of the skin, hair, and nails. These cells originate in the basal layer of the epidermis, where they undergo continuous proliferation through mitosis.

As new keratinocytes are produced in the basal layer, they begin a process of differentiation and migration upwards towards the skin's surface. During this journey, they undergo significant changes, flattening and accumulating increasing amounts of keratin. This keratinization process is crucial for forming the protective barrier of the skin. By the time they reach the stratum corneum, the outermost layer of the epidermis, the keratinocytes have lost their nucleus and organelles, becoming dead, flattened cells called corneocytes. These corneocytes are then shed from the skin surface in a continuous process called desquamation.

Keratinocytes play a vital role in protecting the body from external threats, including mechanical damage, dehydration, and pathogen invasion. They also contribute to wound healing by migrating to cover damaged areas. The health and proper functioning of keratinocytes are essential for maintaining skin integrity and overall health. Conditions affecting keratinocytes can lead to various dermatological issues, such as psoriasis, eczema, and certain types of skin cancer.