Sensing of viral infection and activation of innate immunity by toll-like receptor 3.
Toll-like receptors (TLRs) form a major group of transmembrane receptors that are involved in the detection of invading pathogens. Double-stranded RNA is a marker for viral infection that is recognized by TLR3. TLR3 triggering activates specific signaling pathways that culminate in the activation of NF-kappaB and IRF3 transcription factors, as well as apoptosis, enabling the host to mount an effective innate immune response through the induction of cytokines, chemokines, and other proinflammatory mediators. In this review, we describe the paradoxical role of TLR3 in innate immunity against different viruses and in viral pathogenesis but also the evidence for TLR3 as a "danger" receptor in nonviral diseases. We also discuss the structure and cellular localization of TLR3, as well as the complex signaling and regulatory events that contribute to TLR3-mediated immune responses.
Vercammen
Elisabeth
E
Department for Molecular Biomedical Research, VIB, Ghent, Belgium.
Staal
Jens
J
Beyaert
Rudi
R
D033942:Adaptor Proteins, Vesicular Transport / Q000378:metabolism; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism; D006801:Humans; D007113:Immunity, Innate; D007249:Inflammation / Q000276:immunology; D008024:Ligands; D010766:Phosphorylation; D012313:RNA / Q000502:physiology; D012327:RNA Virus Infections / Q000276:immunology*; D012330:RNA, Double-Stranded; D012367:RNA, Viral / Q000502:physiology; D011971:Receptors, Immunologic / Q000378:metabolism; D015398:Signal Transduction; D051196:Toll-Like Receptor 3 / Q000737:chemistry / Q000502:physiology*; D014443:Tyrosine / Q000378:metabolism
D033942:Adaptor Proteins, Vesicular Transport; D008024:Ligands; D012330:RNA, Double-Stranded; D012367:RNA, Viral; D011971:Receptors, Immunologic; C470409:TICAM1 protein, human; C495344:TLR3 protein, human; D051196:Toll-Like Receptor 3; D014443:Tyrosine; D012313:RNA