FITC-FXII binding to HUVECs in suspension.

(A) HUVECs (4 × 10⁴ cells per well) in suspension were incubated with 1 to 200 nM FITC-FXII for 120 minutes at 37°C over a PVDF membrane in the presence (●) or absence (▪) of 10 μM ZnCl₂. The specific binding curve (▴) is calculated by subtracting binding in the absence of Zn²⁺ from binding in the presence of Zn²⁺. (B) HUVECs (4 × 10⁴cells per well) in suspension were incubated with 70 nM FITC-FXII for 0 to 180 minutes at 37°C over a PVDF membrane in the presence (●) or absence (▪) of 10 μM ZnCl₂. The specific binding curve (▴) is shown. At the end of the incubation, the cells were washed and the HUVEC-bound FITC-FXII was quantified by using CytoFluor4000 plate reader. The results presented are the means ± SEM of 3 to 5 independent experiments.