Effect of ATRA on integrated PCA of cytokine-primed APL cells. Cytokine-primed APL cells were treated with or without ATRA for the indicated time and then incubated with MDP from healthy controls. (A) Coagulation time was measured using a recalcification-time assay. (B) Fibrin production was measured by turbidity at 405 nm (optical density 405 [OD₄₀₅]). (C-D) For inhibition assays, ATRA-differentiated APL cells were treated with DNase I, anti-TF antibody, or lactadherin before incubation with plasma. Coagulation time and fibrin formation were then evaluated. (E-F) Inhibition assays were also performed using APL cells treated with PBS as a control. Data are representative of 4 independent experiments and are displayed as mean ± SD. *P < .05, **P < .01 vs day 0; ^#P < .05, ^##P < .01 vs ATRA-treated group in panels A-B; *P < .01, **P < .001 vs no inhibitor treated group in panels C-F.