Figure 3. KCC activity regulated the NADPH oxidase of human neutrophil.

A, the phosphorylation of phox units in human neutrophils. A representative immunoblot showed the phosphorylation levels of p40^phox in human neutrophils at various experimental conditions. The control group was neutrophils treated with 0.1% DMSO alone. The detailed protocols for neutrophil stimulation were described in Methods. B and C, PMA induced the membrane recruitments of phox units (p47^phox, p40^phox and p67^phox). PMA caused the puncta formation of p47^phox, especially at the membrane periphery (B). DIOA, but not bumetanide, reduced the PMA-provoked membrane recruitment of p47^phox proteins. Other oxidase components such as p40^phox and p67^phox also remained diffusely distributed in cytoplasm during latency. PMA induced the assembly of p40^phox and p67^phox into complexes that were recruited to the juxta-membrane region (C). D, the quantitative analyses for the membrane recruitment of different phox units at various experimental conditions. Each value represents the mean ± SEM from three different experiments by analysing at least 30 cells. *P≤ 0.05, **P≤ 0.01, ***P≤ 0.005. Scale bar, 2 μm.