Toll-like receptor 7 and Toll-like receptor 8 (TLR7 and TLR8)

Toll-like receptor 7 (TLR7) and toll-like receptor 8 (TLR8) are endosomal pattern recognition receptors that detect viral single-stranded RNA and synthetic analogs, acting as key sensors of pathogen-associated molecular patterns (PAMPs). They share significant structural homology, are part of the innate immune system, and initiate signaling cascades that lead to the production of type I interferons (notably IFN-α) and proinflammatory cytokines through the MyD88-dependent pathway. TLR7 is mainly expressed in plasmacytoid dendritic cells, B cells, and some myeloid cells; TLR8 is prominent in monocytes, dendritic cells, and granulocytes. Both receptors are recognized therapeutic targets for infections, immune modulation, cancer immunotherapy, and treatment or mitigation of autoimmune and inflammatory diseases, with a variety of agonists and antagonists under preclinical and clinical study. Their function is central to both disease defense and dysregulation, making them focal points for drug development and biomarker research.

Other names

TLR7 (CD287)TLR8 (CD288)Toll-like receptor 7Toll-like receptor 8

Agonists: Bind and activate TLR7 and/or TLR8, promoting dimerization and triggering downstream MyD88-dependent signaling, resulting in production of type I interferons and proinflammatory cytokines. Antagonists: Bind to distinct or overlapping pockets to stabilize inactive conformations and inhibit signal transduction.