Dose-response curve of DC permeabilization following ATP treatment: effect of Ca²⁺ and Mg²⁺ chelation.

(A) DCs were treated with different concentrations of ATP (0.01 to 20 mmol/L) and exposed to ethidium bromide (10 μmol/L) for 15 minutes at 37°C. The experiments were performed in RPMI 1640 medium alone (circle) or in the presence of EDTA (5 mmol/L) (triangle). The dose-response curves were also plotted based on the P_2Z/P2X₇ active ligand ATP⁴⁻concentration calculated from the experiments performed in RPMI 1640 medium alone (B) or in the presence of EDTA (C). Plotted data represent the mean ± SD of 3 distinct experiments.