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Toll-like receptors: critical proteins linking innate and acquired immunity

Nature Immunology volume 2, pages 675–680 (2001)Cite this article

Abstract

Recognition of pathogens is mediated by a set of germline-encoded receptors that are referred to as pattern-recognition receptors (PRRs). These receptors recognize conserved molecular patterns (pathogen-associated molecular patterns), which are shared by large groups of microorganisms. Toll-like receptors (TLRs) function as the PRRs in mammals and play an essential role in the recognition of microbial components. The TLRs may also recognize endogenous ligands induced during the inflammatory response. Similar cytoplasmic domains allow TLRs to use the same signaling molecules used by the interleukin 1 receptors (IL-1Rs): these include MyD88, IL-1R–associated protein kinase and tumor necrosis factor receptor–activated factor 6. However, evidence is accumulating that the signaling pathways associated with each TLR are not identical and may, therefore, result in different biological responses.

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Figure 1: Regulation of TH cell development by TLRs on APCs.
Figure 2: The IL-1R–TLR signaling pathway.
Figure 3: TLRs and their ligands.
Figure 4: The MyD88-dependent and independent pathways in TLR4 signaling.

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Acknowledgements

We thank lab members for useful discussions and M. Lamphier for critical reading of the manuscript. Supported by grants from the Ministry of Education, Culture, Sports, Science and Technology in Japan.

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Authors and Affiliations

  1. Department of Host Defense, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871, Japan

    Shizuo Akira, Kiyoshi Takeda & Tsuneyasu Kaisho

  2. SORST, Japan Science and Technology Corporation, Japan

    Shizuo Akira, Kiyoshi Takeda & Tsuneyasu Kaisho

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Akira, S., Takeda, K. & Kaisho, T. Toll-like receptors: critical proteins linking innate and acquired immunity. Nat Immunol 2, 675–680 (2001). https://doi.org/10.1038/90609

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