Time courses of inactivation of M662C/D1828C FVIIIa variants by APC and
protein S (PS) or FV. Activity of thrombin-activated FVIIIa
variants was monitored over time by FXase assay. A, FVIIIa with 2.5
nm APC. B, FVIIIa with 2.5 nm APC and 100
nm protein S. Inset, FVIIIa with 2.5 nm APC and
12 nm FV. ▵, ▴, M662C/D1828C; ○, •,
M662C/D1828C/R336Q; □, ▪, M662C/D1828C/R562Q. Two to three
experiments were averaged together. M662C/D1828C inactivation was fit to a
double exponential decay. M662C/D1828C/R336Q and M662C/D1828C/R562Q were fit
to single exponential decay curves. Standard deviations are shown as error
bars.