Figure 4.

Inhibition of Toll and IL-1 receptor pathway members by a dominant-negative ECSIT mutant. (A) 293κB–LUC cells were transfected with 0.5 μg of the constitutively active human Toll mutant CD4/TLR4 and either vector control DNA (−) or indicated amounts of ECSITΔ. DNA concentration in all transfections was equilibrated to 2 μg with vector. Twenty-four hours after transfection, lysates were assayed for luciferase activity. (B) 293κB–LUC cells were transfected with the indicated DNAs and assayed as above. The different constructs were RIP wild type, IRAK cytoplasmic domain fused to CD4 transmembrane and extracellular domain, and different amounts of ECSITΔ as indicated.