TLR3 in antiviral immunity: key player or bystander?
Toll-like receptor 3 (TLR3), which recognizes double-stranded (ds)RNA, was the first identified antiviral TLR and, because dsRNA is a universal viral molecular pattern, TLR3 has been assumed to have a central role in the host response to viruses. However, this role has recently been questioned by in vivo studies and the discovery of several other antiviral pattern-recognition receptors. In this review, the function of TLR3 in the context of these other receptors, namely TLR7, 8 and 9 and the newly identified dsRNA-receptor retinoic-acid inducible gene-I (RIG-I) is discussed. Also, recent research concerning the expression profile of TLR3, its evasion by viruses and a potential role in crosspriming is addressed, which reveals a clearer appreciation of the contribution of TLR3 to antiviral immunity.
Schröder
Martina
M
Viral Immune Evasion Group, Department of Biochemistry, Trinity College Dublin, College Green, Dublin 2, Ireland.
Bowie
Andrew G
AG
D000818:Animals; D000956:Antigens, Viral / Q000276:immunology; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology; D018448:Models, Immunological; D020365:RNA Helicases / Q000276:immunology; D012330:RNA, Double-Stranded / Q000276:immunology; D011971:Receptors, Immunologic; D014777:Virus Diseases / Q000276:immunology*
D000956:Antigens, Viral; D012330:RNA, Double-Stranded; D011971:Receptors, Immunologic; C452820:RIGI protein, human; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases; D020365:RNA Helicases