(A) HSVECs were incubated with various concentrations of NETs for 8 hours, followed by washing and determination of plasma clotting activity of the intact monolayers as described in Materials and Methods. N = 4. (B) HSVECs were incubated with NETs (0.5 µg DNA/ml) as in (A) for 6 hours, followed by cell lysis and determination of plasma clotting activity. N = 7. (C–D) HSVECs were incubated with NETs (0.5 µg DNA/ml) or left unstimulated for 6 hours. TF activity of cell lysates was measured in the presence of various concentrations of anti-TF neutralizing antibody (C). The plasma clotting activity of cell lysates was determined in the presence or absence of 50 µg/ml anti-TF neutralizing antibody or control IgG (D). N = 5. P values: *<0.05, **<0.01, ****<0.0001 vs. the respective controls (A, B, and D) or vs. NETs alone (C). N.S., not significant.