Figure 2.

Dependence of ascorbate recycling on time and extracellular ascorbate concentrations. Intracellular ascorbate was measured by scintillation spectrometry and is shown as mM (left axis) and nmol/mg protein (right axis). Neutrophils were incubated with E. coli CP9 (effector/target ratio 28:1) for the indicated times with extracellular ascorbate concentrations of 10 μM (▪), 25 μM (□), 50 μM (▴), 75 μM (▵), 100 μM (•), and 200 μM (▿). Control neutrophils (○) were incubated without bacteria and 100 μM ascorbate for the times indicated. (Inset) Dependence of recycling on extracellular ascorbate concentrations at one fixed time. Neutrophils were incubated with (•) or without (○) E. coli CP9 (effector/target ratio, 28:1) and the indicated extracellular ascorbate concentrations for 30 min. The y axis is the same as in Fig. 2.