Efficacy of the STAT-1 decoy oligodeoxynucleotide (ODN) treatment in synoviocytes and macrophages in vitro. (a) Electrophoretic mobility shift analysis with extracts from synoviocytes stimulated by IFN-γ (250 U/ml, 30 minutes) and pre-treated (4 h before stimulation) with STAT-1 decoy ODN or STAT mutant ODN (STAT mut; 10 μM each). (b) Activation of STAT-1 and STAT-3 in IFN-γ-stimulated synoviocytes (250 U/ml IFN-γ, 30 minutes) was confirmed by gel shift supershift analysis with specific IgG antibodies. In addition, a 100-fold excess of the unlabelled compensatory sis-inducible element (comp. SIE) gel shift ODN abolished the STAT band, thus verifying the specificity of the detected band. (c) Statistical summary of the effect of STAT-1 decoy ODN (10 μM, 4 h pre-incubation) on CD40 mRNA expression in LPS/IFN-γ (1 μg/ml LPS plus 500 U/ml INF-γ)-stimulated RAW-264.7 macrophages after 12 h (n = 3 to 4, *P ≤ 0.05 versus LPS/IFN-γ). The mutant control ODN had no effect on CD40 expression. The insert shows a representative RT-PCR analysis (amplification of elongation factor-2 (EF-2) cDNA served as an internal standard).