Dendritic cells: the host Achille's heel for mucosal pathogens?

Mucosal surfaces represent the main sites of interaction with environmental microorganisms and antigens. Sentinel cells, including epithelial cells and dendritic cells (DCs), continuously sense the environment and coordinate defenses for the protection of mucosal tissues. DCs play a central role in the control of adaptive immune responses owing to their capacity to internalize foreign materials, to migrate into lymph nodes and to present antigens to naive lymphocytes. Some pathogenic microorganisms trigger epithelial responses that result in the recruitment of DCs. These pathogens hijack the recruited DCs to enable them to infect the host, escape the host's defense mechanisms and establish niches at remote sites.