Time course of PMA-stimulated TF synthesis in HL-60 cells. TF gene expression was induced in HL-60 cells with 1 μmol/L PMA. The X-axis is the time after the addition of PMA. At each time point the intact cells were assayed for TF PCA after the addition of 10 μmol/L ionomycin or 0.1% DMSO. The cell samples were then disrupted by freezing and thawing (5×) and reassayed.