Morphological characteristics of Langerhans cells

Langerhans cells are part of the widely distributed antigen-presenting cells known as den­dritic cells with a key role in immune responses. These specialised bone marrow-derived cells were originally found in the epidermis and later demonstrated in the mucosa of other organs. Langerhans cells are difficult to identifiy in sections stained with hematoxylin-eosin. A lar­ge number of surface and/or cytoplasmic antigens have been localised on Langerhans cells for immunohistochemical detection. The Birbeck granules are the specific markers of Lan­gerhans cells on electron microscopical level. Langerhans cells represent the primary immu­ne defence of the skin and mucosae with various immunological functions, among which the processing and presenting antigen to T lymphocytes are the most important.