Table 1.

Characteristics of FV levels (medium) and APCsr (purified preparations) in FV-WT and mutants

FV mutants	FV:C ∗,‡	FV:Ag ∗,§	Specific activity (fold)	APCsr †,‖
	U/dL	μg/mL	U/μg
FV-WT	21.3 ± 1.3	2.35 ± 0.18	0.091 (1.00)	2.12 ± 0.18
FV-A2086D (FVBesançon)	2.3 ± 0.1	0.29 ± 0.10	0.079 (0.86)	1.84 ± 0.16
FV-W1920R (FVNara)	3.9 ± 0.1	1.04 ± 0.06	0.038 (0.42)	1.57 ± 0.14
FV-R506Q (FVLeiden)	20.2 ± 1.4	2.43 ± 0.22	0.083 (0.91)	1.24 ± 0.04

Measurements were performed as described in “Materials and methods.” All data were measured 3 times, and the average ± standard deviation values are shown.

^∗Data from supernatant in media.

^†Data from purified preparations.

^‡FV:C, FV activity was measured by using a PT-based 1-stage clotting assay.

^§FV:Ag, FV antigen level was measured by an ELISA.

^‖APCsr, APC sensitive ratio was measured by an aPTT-based assay as described in supplemental Methods.