FIGURE 4.

Redox-related changes in cell-surface TF-procoagulant activity. A, shown is the effect of Annexin-V on H₂O₂-stimulated cell-surface TF activity. The cells were exposed to 200 nmol/liter Annexin-V for 15 min after they were treated with 1 mmol/liter H₂O₂ for 15 min. B, shown is the effect of hTrx1-TrxR-NADPH on the response of cell-surface TF activity to H₂O₂. The cells were pretreated with 1 mmol/liter H₂O₂ for 15 min followed by washing twice with PBS, then incubated with 5 μmol/liter hTrx1, 20 nmol/liter TrxR, and 0.2 mmol/liter NADPH at 37 °C for 1 h, which was washed away before the assay of TF activity. C, shown is the effect of hTrx1-TrxR-NADP⁺ on cell-surface TF activity. The cells were treated with 5 μmol/liter hTrx1, 20 nmol/liter TrxR, and 0.2 mmol/liter NADP⁺ at 37 °C for 1 h, which was washed away before assay TF activity. D, shown is the effect of human serum with elevated NADP⁺ levels on cell-surface TF activity. The cells were incubated with 200 μl of human serum or serum plus 0.2 mmol/liter NADP⁺ for 1 h. All data points in A–D are expressed as the means ± S.D., n = 5. *, p < 0.05; **, p < 0.01; N.S., not significant.