Effect of γA/γA and γA/γ′ fibrinogen on the ETP-based APC response in reconstituted fibrinogen-deficient plasma. Thrombin generation was initiated with 10 pM TF in the presence of 0 to 10 nM APC in fibrinogen-deficient plasma supplemented with buffer (A), or with 1.4 mg/mL γA/γA fibrinogen (B), or with 1.4 mg/mL γA/γ′ fibrinogen (C). Residual ETPs (ETP_+APC/ETP_−APC) were plotted as a function of the APC concentration (D). Averages of duplicate experiments are shown.