Figure 1
Effect of TNFα on MMP-9 production in monocytes. We cultured monocytic THP-1 cells in 12-well plates at 1 × 106 cells/well. We then treated the cells with vehicle (BSA), TNFα (10 ng/ml), and LPS (positive control, 10 ng/ml), separately. After 24 h of incubation, we collected the cells and supernatants. (A) We isolated total cellular RNA and determined MMP-9 mRNA expression using real-time PCR. (B) We determined MMP-9 protein levels in culture media using ELISA (C,D) Primary monocytes were treated with vehicle, TNFα or LPS. MMP-9 mRNA expression and protein were determined. (E,F) THP-1 cells were treated with TNFα for different time points (2, 4, 6 or 24 h). MMP-9 mRNA expression and protein were determined. Three independent experiments were performed with similar results. Data are expressed as mean ± SEM (n ≥ 3). One way ANOVA (Dunnett’s Test) for comparing treatments vs control was used. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.
