Iron chelator induces IL-8 protein secretion (A, C) and IL-8 mRNA accumulation (B, D) in IHOK and HN12 cells in a time-dependent manner. Cells were incubated with DFO (1.0 mM) or IL1-β (10 ng/ml) for the indicated time periods. Levels of IL-8 protein and mRNA were determined by ELISA and semiquantitative RT-PCR, respectively. Numbers below the gels represent the intensity of IL-8 mRNA relative to GAPDH mRNA. These data are representative of three independent experiments.