Mechanisms of dendritic cell function.

There is now considerable evidence, from in vivo and in vitro studies, supporting the claim that dendritic cells are the principal accessory cells of the vertebrate immune system. Until recently, however, the biology of the dendritic cell accessory mechanism has remained obscure. Here, Philip King and David Katz review recent findings that have clarified several aspects of this mechanism, providing a possible basis for the potent T-cell stimulating capacity of the dendritic cell, and yielding clues to the ontogenetic relationships of these cells and to their role in immunopathology.