Antigen-presenting cells in allergy.

The complex interaction of the innate and adaptive immune system requires flexibility and cooperation among various cell types. In this regard, antigen-presenting-cells (APCs) play a pivotal role in transferring information from the periphery of the organism to lymphoid organs, where they initiate the activation of naive T cells. Dendritic cells, Langerhans' cells (LCs), and macrophages are also critical in the induction of allergic inflammation by presenting allergens to T lymphocytes and by contributing to the local recruitment of effector cells. Because of a complex genetic background, atopic individuals exhibit a dysregulation of T cell-mediated immune mechanisms. Attempts to understand the role APCs play in these pathophysiologic conditions are in progress and may allow development of new treatment strategies. In this review we will focus on the biology of APCs and their unique role in the induction and control of allergic inflammation.