Shaping the immune response to parasites: role of dendritic cells.

Parasites represent a diverse group of pathogens that often trigger highly polarized immune responses that become tightly regulated during chronic infection. Recent studies have implicated the parasite-dendritic-cell interaction as a key determinant of the host response to these eukaryotic invaders. Dendritic cells appear to be pivotal in the initiation of cellular immunity against parasites as well as in directing Th1/Th2 effector choice. Moreover, there is increasing evidence that parasites regulate dendritic-cell function for the purposes of evading host immunity. This regulation also benefits parasites by protecting their host niche from the potentially lethal consequences of an uncontrolled inflammatory response.