FC-99 is a benzenediamine derivative that inhibits LPS-induced IRAK4 phosphorylation/activation and downstream signaling events (5-45 μM; murine RAW 264.7 & peritoneal macrophages), including IRAK1 (a TLR3 pathway negative regulator) degradation, p38/ERK/JNK activation, and cytokines production. FC-99 inhibits RSV replication (50 μM; A549) and poly(I:C)-indued IRF3/IFN-α/JAK/STAT1 signalling in cultures (0.5-50 μM; murine peritoneal macrophages), and ameliorates sepsis induction following caecal ligation puncture (CLP) in mice in vivo (100/70/32.5% motality in 7 days with 0/30/100 mg/kg i.p. 2 h prior to CLP).
IRAK4 activation and IRAK1 degradation inhibitor that suppresses toll-like receptors (TLRs) cellular signaling and ameliorates sepsis induction in mice in vivo.
FC-99 is known to affect the levels of serum immunoglobulin. It might be therapeutically beneficial in systemic lupus erythematosus.
