VTX-294 activates the NF-κB pathway via TLR8.

(A) Seven TLR agonists were compared. (B) Representative structures of the TLR7/8 agonists used in this study. HEK-293 cells transfected with (C) human TLR7 and (D) TLR8 and an NF-κB-driven reporter SEAP gene were stimulated for 18–24 h with TLR agonists. The y-axis shows the level of SEAP activity in the Quanti-blue™ assay optical density (OD). The x-axis shows the concentration of each compound in µM. Each data point represents the mean ± SD of OD at 650 nm of triplicate culture wells. VTX-217 (black) is a structurally matched negative control for VTX-744 (gray), VTX-087 (purple) and VTX-294 (red). The IMQ benchmarks R848 and CL075 are denoted in blue and green, respectively.