Figure 4. AP-1 activity of human gingival fibroblasts treated with and without 10 µg/mL cyclosporin A and 10 ng/mL TNF- or PDGF. (A) Gel shift assay; 5 µg of nuclear proteins were incubated with labeled [³²P]ATP-labeled oligonucleotide probe, separated, and visualized by autoradiography, as described in the "METHODS". For competition, unlabeled nucleotide was added at 100-fold molar excess. Arrows indicate shifted complexes. (B) Luciferase reporter activity normalized for β-actin Renilla luciferase control. Mean ± SD of triplicates is shown (p < 0.025).