Toll-like receptor 7 (TLR7) (inhibitor)

Class

Monoclonal antibody (TLR7 antagonist)

Pathway

Innate immune TLR7 signaling

Notes

original target text: Toll-like receptor 7 (TLR7)

Toll-like receptor 7 (TLR7) is a pattern-recognition receptor of the innate immune system that detects single-stranded RNA, normally a signal of viral infection. It resides inside endosomes of specialized immune cells, including plasmacytoid dendritic cells and B lymphocytes, and upon engagement triggers intracellular signaling that culminates in production of type I interferons and pro-inflammatory cytokines. This response is protective during viral infection, but TLR7 can also be activated inappropriately by a person's own RNA-containing material, particularly RNA bound in immune complexes. Chronic, self-directed TLR7 signaling is implicated in autoimmune conditions such as systemic lupus erythematosus, where sustained interferon output and B-cell activation contribute to autoantibody formation and tissue damage. Blocking TLR7, for example with a monoclonal antibody that prevents the receptor from engaging its RNA ligand or from signaling downstream, is a strategy aimed at reducing this pathological innate-immune drive without eliminating the entire immune system. This mechanism is relevant broadly to autoimmune and inflammatory diseases in which excessive nucleic-acid sensing is thought to sustain disease activity, and reflects a wider therapeutic interest in modulating the interferon pathway.