Resolution of neutrophilia and macrophage reprogramming are enhanced by pioglitazone even when administered after onset of inflammation in CGD. Twenty-four hours after zymosan injection, mice were treated by oral gavage with a single dose of either vehicle or pioglitazone. At 48 hours after zymosan, peritonea were lavaged, and cells were analyzed as before. The course of neutrophilia is shown in panel A: solid lines represent time course of zymosan-induced peritoneal neutrophilia without treatment derived from data shown in Figure 3A; arrow shows the time at which pioglitazone or vehicle was administered; dashed lines show changes in neutrophilia following treatment. Accumulation of apoptotic neutrophils (B) and efferocytosis by macrophages (C) in peritonea at 48 hours are shown. (D) Cytokines were measured in lavage supernatants by enzyme-linked immunosorbent assay. (E) F4/80 positive macrophages were analyzed for PPARγ, CD36, and MMR by flow cytometric analysis as in Figure 1. Data represent mean ± SE; N = 8 mice per treatment group. #P ≤ .02 compared with vehicle-treated CGD mice, and *P ≤ .01 compared with vehicle-treated WT mice.