Читать книгу Ridley's The Vulva - Группа авторов - Страница 111

Langerhans cells are found in the epidermis and are bone‐marrow‐derived dendritic cells, present in all layers of the epidermis. They lack pigment and represent 1–2% of the epidermal cell population and are located mainly in the suprabasal area. An analysis of the distribution of Langerhans cells in healthy tissue of the genital tract showed there were 19 per 100 basal squamous cells in the vulva [36]. They contain characteristic Birbeck granules, shaped like a tennis racquet in their cytoplasm. Each cell possesses five to nine dendritic processes, which extend out in the same horizontal plane.

Langerhans cells are antigen‐presenting cells, taking up the antigen and transporting it to the lymph node. They play an important immunological role in the skin and are involved in the sensitisation and activation of contact allergic dermatitis as well as participating in the immune surveillance of the skin. These immunological functions are particularly important in the lower female genital tract as these sites are exposed to a wide range of antigens. They may be involved in oncogenic HPV infection, and it has been shown that Langerhans cell counts are lower in HIV patients with vulval intraepithelial neoplasia [37].