Role of Toll like receptor-activated dendritic cells in the development of autoimmunity

The recognition of microbial stimuli by Toll-like receptors (TLRs) expressed on dendritic cells (DCs) is essential for the regulation of immune responses. DC activation via TLRs leads to the production of proinflammatory cytokines, chemokines and surface molecules that play a key role in the regulation and control of inflammatory reactions and adaptive immunity. Minor imbalances in the feedback control of TLR-activated innate immune cells have been associated with autoimmunity in genetically prone individuals. We review here recent studies indicating how TLR-mediated activation of innate immune cells, including DCs, may be involved in the development and/or maintenance of autoimmune responses in the presence of both endogenous and exogenous ligands.