Fig. 5: Phosphatidylserine exposure promotes the coagulant activity of apoptotic cells.

acCasp9 3T3 were left untreated or treated with B/B for 2 h (A–C). Annexin V (AxV) was added to cells in a Ca²⁺ containing buffer and incubated on ice for 30 min (A, B, D, E). TF activity was measured as the absorbance at 30 min after addition of live or apoptotic cells to mouse FVII, human FX, and chromogenic FXa substrate (A). Time to fibrin clot formation was measured as the maximum change in absorbance (Time to V_max) after adding Ca²⁺ to citrated mouse plasma containing live or apoptotic cells; lower values indicate more rapid clot formation (B, C). Surface lung metastasis was quantified at 14 days post I.V. injection (D, E). Dotted line represents the absorbance of a control well containing all assay components without cells added (A). Statistical analysis is Welch’s ANOVA with Dunnett’s multiple comparisons test; error bars represent SEM (A, D, E). Circles connected by lines are matched serum samples, and statistical analysis is two-way ANOVA with Tukey’s multiple comparison test (B, C).