Antigen presentation by Langerhans cells

Langerhans cells and other skin-resident dendritic cells (DC) are required for the development of cutaneous adaptive immune responses. In vivo experiments using mice with selective DC-subset deficiencies and ex vivo experiments using isolated DC suggests that each subset makes a unique contribution to the adaptive response. This review focuses on the functional outcome of antigen presentation by Langerhans cells. Special attention is given to their ability to promote CD4 T cell differentiation in a variety of inflammatory contexts and whether this subset has the capacity to cross-prime CD8 T cells.

► CD103+ dDC, not LC are responsible for cross-priming. ► LC promote Th17 in response to extracellular pathogens. ► LC promote Th2 in response to epicutaneous immunization. ► Presentation by LC may result in T cell anergy/deletion.