Figure 3.

Oxidation of GSH in P. aeruginosa during phagocytosis by human neutrophils. PAO1 (1 × 10⁸/ml) grown on CELTONE Complete ¹³C-medium was incubated with neutrophils (1 × 10⁷/ml) at 37 °C with end–over–end rotation. At the indicated time points, phagocytosis was stopped by placing the mixtures on melting ice; NEM (20 mm) was added, and neutrophils and bacteria were lysed. [¹³C]GSH (A), [¹³C]GSSG (B), [¹³C]GSSX (C), and [¹³C]GSA (D) were measured by stable isotope dilution LC-MS/MS. A significant difference when compared with time 0 was identified by ANOVA with Dunnett's multiple comparison test and is indicated by * (p < 0.05), ** (p < 0.01), or *** (p < 0.001). Data were obtained for at least three different donors and presented as mean ± S.D. E, individual glutathione species are presented as a percentage of total glutathione as described in Fig. 2. Data are presented as means from at least three independent experiments.