TF^C209S disulfide mutant can be decrypted similar to the wild-type TF. Human umbilical vein endothelial cells cultured in 24-well plate were transduced with varying concentrations (MOI/cell) of adenovirus encoding wild-type (WT) TF or TF^C209S. (A) After culturing cells for 48 hours, the cell lysates were harvested, subjected to nonreducing sodium dodecyl sulfate–polyacrylamide gel electrophoresis, and immunoblotted for TF using polyclonal anti-TF antibodies. (B) Intact cell monolayers were used to measure cell-surface TF activity by measuring the rate of factor Xa generation after addition of FVIIa (10nM) and factor X (175nM). (C) Cell lysates were made by repeated (3×) freeze-thaw of cell monolayers and diluted 10× before they were used to measure TF activity as in Figure 1B. (D). Fold increase in TF activity upon cell lysis was calculated by the rate of FXa generation in cell lysates divided by the rate of FXa generation at the cell surface. Note: In these experiments, unlike the data shown in our recent report,¹  we have not quantified the levels of TF or TF-FVIIa complexes at the cell surface; therefore, one should not extrapolate these data to TF-specific activity.