Analysis of circulating TF activity. TF enzymatic activity was measured in (A) PPP collected from Flox/flox (n = 4) and Flox/flox/Cre (n = 4) mice; and (B) circulating MPs isolated from PPP of C57BL/6 (n = 5), Flox/flox (n = 4), and Flox/flox/Cre (n = 6) mice. Blood was collected at the time of kill in animals not subjected to FeCl₃ injury. TF activity was measured by 2-stage colorimetric Xa generation assay and is expressed as pM factor Xa/min. P = NS for all groups.