Final answer:
Dendritic cells respond to parasite infections by presenting antigens which activate naive CD4+ T cells, leading to their development into helper T cells that play a key role in the immune response.
Step-by-step explanation:
When a parasite infection occurs, dendritic cells, which are a type of antigen-presenting cell (APC), process and present antigens on their surface. This interaction, facilitated by MHC II molecules, promotes the activation of naive CD4+ T cells. Once activated, these naive T cells differentiate into helper T cells (TH). Helper T cells have a pivotal role in the immune system; they can activate B cells and CD8+ T cells, which in turn become cytotoxic T cells capable of destroying infected cells. The secretion of cytokines by helper T cells is also crucial as it helps regulate various aspects of the immune response. Dendritic cells are thus essential in initiating a robust adaptive immune response following a parasitic infection.