The Migration of Human Follicular Dendritic Cell-Like Cell Is Facilitated by Matrix Metalloproteinase 3 Expression That Is Mediated through TNFα-ERK1/2-AP1 Signaling

Figure 2

MMP3 expression induced by TNFα is mediated through ERK1/2 and AP1 activation in FDCLC. (a) TNFα induces ERK1/2 phosphorylation in FDCLCs. Time-course TNFα-treated FDCLCs were harvested and lysed, and ERK1/2 phosphorylation was then assessed by western blotting. The ImageJ densitometry plug-in was used for quantitative analysis. Among the MAPKs tested, only ERK1/2 phosphorylation was found to be significantly induced by TNFα. (b) TNFα-induced MMP3 expression is dependent on ERK1/2 activation. FDCLCs were pretreated with the ERK1/2 inhibitors U0126 and PD98059, and MMP3 secretion in the culture supernatant was analyzed. The inhibition of ERK1/2 phosphorylation was confirmed by western blotting, and MMP3 secretion was analyzed by ELISA. (c) Luciferase reporter assay for the AP1 binding site in the MMP3 promoter region. Diagrams indicate the vectors used. The MMP3p and AP1 luciferase activity was increased by TNFα, but not that of the AP1-mutated Mmp3p construct. Data shown are the mean values with standard deviation (SD) of three independent biological replicates; .

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