Accessory and adhesion molecules expressed on murine epidermal Langerhans cells and the modulation by cytokines

Langerhans cells (LC) are MHC class II (Ia)-positive dendritic cells that act as an antigen-presenting cells for T cell-dependent immune responses. LC originate from cells in bone marrow and migrate into the epidermis through blood vessels. LC also migrate from the epidermis to regional lymph nodes after antigen stimulation where they present antigens to T cells. These are the essential features of LC. The morphological and functional properties of LC are modulated by external stimuli or various cytokines. In this review we focus on the accessory and adhesion molecules on LC and describe how these molecules are modulated by cytokines. We also describe the molecules participating in the migration of LC into and from the epidermis. Moreover, we introduce our data obtained from purified murine epidermal LC and from the transgenic mice overexpressing several cytokines in the epidermis. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.