LPS-induced expression of IFN-β and IFN-λ1 is proportional to the number of κB sites. (A) Western blot analysis of the efficiency of siRNA-mediated RelA knockdown in HEK293-TLR4/CD14-Md2 cells using a range of siRelA concentrations (0.1hyphen]30nM). (B) Dose-dependent inhibition of IFNβ and IFN-λ1 mRNA expression in HEK293-TLR4/CD14-Md2 cells and stimulated with LPS (1 μg/mL). The x-axis shows percent RelA expression relative to control (100%) based on the densitometry analysis of Western blots. The y-axis is fold induction over mRNA expression in resting cells. Data shown are the mean + SD from a representative of 2 independent experiments.