GSK669 inhibits NOD2 but not NOD1 mediated responses.

(A) Structure of GSK669, the original hit identified from the NOD2 HTS screening cascade. (B) Concentration response curves showing GSK669 selectively inhibits MDP-stimulated IL-8. IL-8 secretion in either MDP treated 293/hNOD2 or iE-DAP treated 293/hNOD1 stable cell lines was measured in the presence of increasing concentrations of GSK669. Data are mean ± SD from 6 independent assays. (C) Selective inhibition of NOD2-mediated MAPK phosphorylation by GSK669. Serum-starved 293/hNOD1 or NOD2 stable cells were pre-incubated with compound at the concentrations indicated and then stimulated for 1 hour with either Tri-DAP or MDP, respectively. Phospho-p38, JNK and ERK1/2 were identified in cell lysates by western blotting. A RIP2 inhibitor compound was used as a positive control. Similar results were obtained in 5 (293/hNOD2) and 2 (293/hNOD1) separate experiments.