Chapter summary Immune responses are initiated in the T-cell areas of secondary lymphoid
organs where naïve T lymphocytes encounter dendritic cells (DCs) that present antigens
taken up in peripheral tissues. DCs represent the interface between the universe of foreign
and tissue-specific antigens and T lymphocytes, and they are the key players in the
regulation of cell-mediated immunity. We discuss how the nature of the DC maturation
stimuli and the density and quality of DCs present in the T-cell areas of secondary lymphoid …

Dendritic cells are responsible for directing different types of T cell responses, from thymic
negative selection to the generation of effector and memory cells and the induction of
peripheral tolerance. Recent studies indicate that the dendritic cell lineage, the extent of
recruitment into inflamed tissues and migration to lymph nodes, the nature of maturation
stimuli and the kinetics of activation have a quantitative and qualitative impact on T cell
stimulation, thus exerting an instructive control on T cell responses.