Figure 6. The inhibition of IRAK4 does not prevent the IL-1-stimulated activation of IKKβ and MAP kinases in IL-1R cells.

IL-1R cells were incubated for 1 h without (−) or with (+) 3 µM IRAK4-IN-1 to inactivate cellular IRAK4, and then stimulated with IL-1β. Cell extract (20 µg of protein) was subjected to SDS–PAGE and immunoblotting with antibodies recognizing all forms of IRAK1, JNK, p38α MAP kinase and GAPDH, and antibodies that recognize the phosphorylated (p) forms of p105/NF-κB1, JNK1/2 and p38α MAP kinase.