The dynamics of dendritic cell–T cell interactions in priming and tolerance

Induction of T cell priming and tolerance require direct encounters between naïve T cells and dendritic cells (DCs). T cell activation and proliferation occur in both situations, but the concomitant dynamics of DC–T cell contacts differ: the contacts between naïve T cells and DCs are more stable during the induction of priming than during the induction of tolerance. However, the extent of the differences between the dynamics of the contacts, and the contribution of contact duration and frequency to the functional T cell outcome, remain a matter of debate. Recently, experimental models have been developed to address the role of contact stability in T cell function in vivo, which use real-time imaging of DC–T cell interactions.