Toll-like receptors (TLRs) are a critical part of the innate immune response, and are expressed on macrophages and dendritic cells. TLRs are pattern-recognition receptors, and recognize molecules derived from microbes. Once activated, TLRs result in activation of innate immunity by inducing production of proinflammatory cytokines and upregulation of costimulatory molecules
TLR signaling pathways are separated into two groups: a MyD88-dependent pathway that leads to the production of proinflammatory cytokines with quick activation of NFkB and MAPK; and a MyD88-independent pathway associated with the induction of IFN-beta and IFN-inducible genes, and maturation of dendritic cells with slow activation of NFkB and MAPK.
Proteins on this pathway have targeted assays available via the [Assay Portal](https://assays.cancer.gov/available_assays?wp_id=WP75 CPTAC).