Information HS-243 HS-243 is a highly potent interleukin-1 receptor-associated kinase (IRAK) inhibitor with IC50 of 24 nM, 20 nM and 0.5 μM for IRAK-1, IRAK-4 and TAK1, respectively. Targets IRAK-4 (Cell-free assay); IRAK-1 (Cell-free assay); TAK1 (Cell-free assay) 20 nM; 24 nM; 0.5 μM In vitro HS-243 has exquisite selectivity toward both IRAK-1 (IC50 = 24 nM) and IRAK-4 (IC50 = 20 nM), with only minimal TAK1-inhibiting activity (IC50 = 0.5 μM). Using HS-243 and takinib, we evaluates the consequences of cytokine/chemokine responses after selective inhibition of IRAK-1/4 or TAK1 in response to lipopolysaccharide challenge in human rheumatoid arthritis fibroblast-like synoviocytes. HS-243 specifically inhibits intracellular IRAKs without TAK1 inhibition and these kinases have distinct, nonredundant signaling roles. Cell Research(from reference) Cell lines：RA-FLS cells, THP-1 cells Concentrations：10 μM Incubation Time：24 h