Langerhans cells, veiled cells, and interdigitating cells in the mouse recognized by a monoclonal antibody

dendritic cells (DC) form a group of non]ymphoid dendritic cells (NLDC) postulated to act primarily as antigen-presenting or accessory cells, in particular as inducers of T-dependent responses (1-5). The cells originate from bone marrow (3, 6, 7), but although it has been suggested that they belong to the mononuclear phagocyte system (8, 9), a direct relationship with monocyte] macrophage populations has not yet been proven. In contrast to typical macrophages, these DC show little phagocytic activity (10-12), whereas high levels of Ia antigens are constitutively expressed (13-16). LC are described as the primary immunocompetent cell in the skin, playing a role in the presentation of antigen to T cells and the induction of contact sensitivity (2, 4, 17). They can migrate from the skin into the afferent lymph (18, 19) as VC, characterized by their long, actively moving processes (19, 20). During their travel via the afferent lymph, VC can carry antigen, which may be presented to lymphocytes in the draining lymph node (21). Based on morphological criteria and localization patterns after cell transfer, it has been hypothesize