Venous thrombosis model at 250 IU/kg. The intravital thrombosis assay: an electrolytic injury was delivered to the surface of a mouse femoral vein for 30 seconds (1.5 V anodal current) after the injection of fluorophore labels for fibrin (A) and platelets (B) captured with time-lapse fluorescence imaging from 1 to 60 minutes later. Data are quantitated and normalized every video frame showing comparative levels for WT (blue), FIX knockout mice without treatment (red), or FIX knockout mice with 250 IU/kg BeneFIX injected 6 hours prior to thrombus induction (green lines), using a group of 5 to 6 mice per genotype and treatment. Data are means; errors bars are standard error of the mean. There are no statistical differences between the WT and HemB mice with BeneFIX treatment, whereas the untreated HemB mice had lower levels of accumulation for both thrombotic parameters (P < .001 at 10 or more minutes; analysis of variance).