Recognition of microbial infection and initiation of host defense responses is controlled by multiple mechanisms. Toll-like receptors (TLRs) have recently emerged as a key component of the innate immune system that detect microbial infection and trigger antimicrobial host defense responses. TLRs activate multiple steps in the inflammatory reactions that help to eliminate the invading pathogens and coordinate systemic defenses. In addition, TLRs control multiple dendritic cell functions and activate signals that are critically involved in the initiation of adaptive immune responses. Recent studies have provided important clues about the mechanisms of TLR-mediated control of adaptive immunity orchestrated by dendritic cell populations in distinct anatomical locations.
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We dedicate this review to to the memory of Charles A. Janeway, Jr. Supported by Howard Hughes Medical Institute (R.M.) and National Institutes of Health (AI46688 and AI05502 to R.M. and AI054359 to A.I.).
The authors declare no competing financial interests.
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Iwasaki, A., Medzhitov, R. Toll-like receptor control of the adaptive immune responses. Nat Immunol 5, 987–995 (2004). https://doi.org/10.1038/ni1112
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