Release of HBP and elastase from HL60 cells.

HL60 cells were incubated in the absence of a stimulus or in the presence of PMA (100 nM) or ionomycin (0.5 μM) for 30 minutes at 37°C. Cells were spun down, and the concentrations of HBP (A) and elastase (B) in the supernatants were determined by ELISA. Data represent the relative release of HBP and elastase (compared with the total amount of these proteins in lysates) and are the mean ± SD of 4 experiments, each performed in duplicate.