Effect of APC on FVIII-WT/FVIIIa-WT vs FVIII-QQ/FVIIIa-QQ on thrombin generation in reconstituted HA/FVL murine plasma. Thrombin generation was evaluated in the presence of increasing APC concentrations in FVIII-reconstituted HA/FVL murine plasma with 4 µM of PCPS and 7.5 mM of CaCl₂. (A) HA/FVL plasma was either reconstituted with 1 nM of FVIII-WT (blue squares) or FVIII-QQ (red triangles), and thrombin generation was initiated with FXIa (30 nM). (B) FVIII (1.5 nM) was activated with thrombin (30 nM) for 30 seconds and quenched with hirudin (60 nM). HA/FVL murine plasma was reconstituted with 0.2 nM of FVIIIa-WT or FVIIIa-QQ. Thrombin generation was initiated with FXIa (400 pM). In both panels, residual peak thrombin represents peak thrombin relative to the 0-nM APC condition. Means ± standard errors of the mean of 4 independent experiments are plotted.