Akademik

Langerhans cells

a stellate type of dendritic cells derived from precursors in the bone marrow; they appear clear on light microscopy, have dark-staining, indented nuclei with inclusions called Birbeck granules in their cytoplasm, and lack tonofilaments, desmosomes, and melanosomes. They are found principally in the stratum spinosum of the epidermis, but also in other stratified epithelia as well as in the lung, lymph nodes, spleen, and thymus. Their surface markers are characteristic of macrophages, and Langerhans cells are antigen-presenting cells involved in contact allergic responses and other cell-mediated immune reactions in the skin.

Langerhans cells identified in a jaw lesion. Immunohistochemical stain for CD1a antigen, specific to Langerhans cells, demonstrates large numbers of brown-staining Langerhans cells.

Medical dictionary. 2011.