Prevention of PDI-dependent TF activation by anti-TF 10H10. (A) CD115-selected spleen cells were stimulated for 15 minutes at 37°C with IgG control (1 µg/mL), anti-β2GPI antibody rJGG9 (1 µg/mL), or HL7G (100 ng/mL) either alone or together with indicated inhibitors (using concentrations given in Figure 1). Cell-associated PCA was subsequently measured by single-stage clotting assay. (B) Murine monocytes were stimulated with antibody and inhibitors in autologous plasma, as indicated, for 10 minutes. Samples were analyzed for PS exposure (Annexin V–FITC binding) by flow cytometry. n = 6; *P < .002; 1-way ANOVA followed by the Dunnett multiple-comparison test. (C) Effect of 10H10 (100 µg/mL) on PDI enhanced FXa generation by soluble TF (sTF)-FVIIa. Data are shown as mean ± SD; *P = .004; **P = .006; 1-way ANOVA followed by the Dunnett multiple-comparison test. (D) Single-stage clotting assay of human MM1 cells. 10H10 was added 15 minutes after aPL stimulation, that is, directly before recalcification. Data are shown as mean ± SD; n = 6; *P ≤ .001; 1-way ANOVA followed by the Dunnett multiple-comparison test. (E) Single-stage clotting assay of human MM1 cells stimulated with monoclonal aPLs or ATG for 15 minutes at 37°C either with or without preincubation of 50 µg/mL 10H10. (F) MM1 cells were stimulated as indicated and PS exposure (Annexin V–FITC binding) was measured using flow cytometry. (G) Single-stage clotting assay of human MM1 cells cultured in 10% human serum. Anti-C5 antibody eculizumab (100 µg/mL) was added 5 minutes before HL5B (100 ng/mL) or ATG (100 µg/mL). Data are shown as mean ± SD; n = 6; *P ≤ .001; 1-way ANOVA followed by the Dunnett multiple-comparison test.