Figure 1.

FXII preferentially binds to apoptotic cells. (A) Biotin-labeled FXII (B-FXII) at the indicated concentrations was incubated with apoptotic CEM cells (2 × 10⁵) at 4°C for 15 min. After washing, the cells were labeled with PE-avidin and analyzed by flow cytometry. The fluorescence tracings shown are representative data from three independent experiments. (B) Viable CEM cells (VC, closed circles) or apoptotic CEM cells (AC, squares) were incubated with B-FXII at the indicated concentrations at 4°C for 15 min. After washing, the cells were labeled with PE-avidin and analyzed by flow cytometry (n = 5). The data were analyzed by Student’s t-test, *p < 0.05; **p < 0.01; ***p < 0.001.