Activation of a κB-TATA-luciferase reporter plasmid after overexpression of NF-κB factors in TF-1 cells. A total of 0.5 μg of plasmids expressing p50, p52, or p65 was cotransfected with 0.5 μg of κB-TATA-luciferase reporter plasmid into TF-1 cells separately or in combination. A tκ-TATA-luciferase reporter lacking κB enhancer (tκ-luc, 0.5 μg) was used as negative control. The total amount of transfected DNA was kept constant by adding appropriate amounts of expression vector without insert. At 48 hours after transfection, cells were collected for luciferase assay. Results are expressed as mean ± standard error of mean (SEM) (× 10³ cpm) for nine samples from three experiments. *Indicates a significant increase above the κB-TATA reporter plasmid (P ≤ .05).