Seminars in Immunopathology

, Volume 29, Issue 1, pp 15–26

Toll-like receptors in the skin

Review

Abstract

Toll-like receptors (TLRs) are important pattern-recognition receptors involved in host defense against a variety of pathogenic microorganisms. Activation of TLRs leads to the production of cytokines, chemokines, antimicrobial peptides, and upregulation costimulatory and adhesion molecules involved in innate and adaptive immune responses. TLRs are expressed on a variety of cell types found in the skin, including keratinocytes and Langerhans cells in the epidermis, resident and trafficking immune-system cells such as macrophages, dendritic cells, T and B cells, and mast cells in the dermis, endothelial cells of the skin microvasculature, and skin stromal cells such as fibroblasts and adipocytes. There have been an increasing number of reports demonstrating that TLRs play a key role in cutaneous host defense mechanisms against bacterial, fungal, and viral pathogens. In addition, TLRs have also been implicated in the pathophysiology of various inflammatory skin diseases.

Keywords

Toll-like receptors TLR Skin Cutaneous Pattern-recognition receptors 

Abbreviations

APCs

antigen-presenting cells

DCs

dendritic cells

HBD

human beta defensin

IRAK

IL-1R-associated kinase

IRF3

interferon regulatory factor 3

LCs

Langerhans cells

MAPK

mitogen-activated protein kinase

MyD88

Myeloid differentiation factor-88

PAMPs

pathogen-associated molecular patterns

PGN

peptidoglycan

PRRs

pattern-recognition receptors

TIR domain

Toll/IL-1 receptor domain

TIRAP

Toll/IL-1 receptor adaptor protein

TLR

Toll-like receptor

TRAF6

TNF receptor-associated factor 6

TRIF

TIR domain containing adapter-inducing IFNβ

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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  1. 1.Division of Dermatology and Department of Microbiology, Immunology and Molecular Genetics, Center for Health SciencesDavid Geffen School of Medicine at UCLALos AngelesUSA

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