Effect of phospholipids on the inhibition of aPC by PCI. (A) aPC (5 nM) was incubated for 20 minutes with different concentration (as indicated) of recombinant PCI in the absence and presence of heparin (2.5 μg/mL) or phospholipids (as shown, 50 μg/mL each) in the presence of 2.5 mM CaCl2. Remaining aPC activity was determined as described in “Materials and methods.” Data shown represent the means of duplicates. Similar results were obtained in at least 3 independent experiments performed with different preparations of recombinant PCI. (B) aPC (5nM) was incubated for 20 minutes with PCI (35 nM) and with different concentrations of OxPAPE or heparin (as shown) in the presence of 2.5 mM CaCl2. Remaining aPC activity was determined as described in “Materials and methods.” Data shown are means of triplicates ± SEM. Similar results were obtained in at least 3 independent experiments.
