Professional antigen-presenting cells (APC) such as dendritic cells (DC) and macrophages play a critical role in the initiation and maintenance of a T cell-mediated immune response. APC are essential for T cell priming, differentiation and activation in lymphoid tissue and at sites of inflammation. Understanding the molecular mechanisms via which APC function can be controlled may give novel insights into how T cell mediated immunity may be induced or blocked. This meeting will highlight current research aimed at inducing dendritic cells with tolerogenic function in order to treat inflammatory disease (e.g. rheumatoid arthritis) as well as work aimed at boosting the immunostimulatory function of dendritic cells in the context of cancer. The meeting will also highlight recent progress on the suppressive effects of CD4+ regulatory T cells on APC function, and how these can be overc