FIGURE 5.

Effect of PI3K-γ inhibition or PI3K-δ inhibition on neutrophil apoptosis and efferocytosis in MSU-induced inflammation. Mice were injected with MSU crystals (100 μg) into the tibiofemoral joint and 12 h later received an injection of AS605240 or GSK045 (50 μM, i.a.). Four hours after treatment, the cells were collected to annexin V analysis (A). Efferocytosis was evaluated in mice injected with MSU crystals (100 μg) into the tibiofemoral joint and 12 h later received an injection of AS605240 or GSK045. Knee was washed 18 h MSU injection and cells were surface-stained with anti-F4/80 for macrophages and then intracellularly stained with anti-Ly6G for neutrophils (B). Results are expressed as the number of leukocytes per cavity and are shown as the mean ± SEM of five mice in each group from one experiment representative of two independent experiments. Significance was calculated using ANOVA followed by Holm-Sidak’s multiple comparison test. The exactly p-value are shown in the figure. (C) Expression of p-IκBα by Western Blot in synovial tissue collected 18 h after MSU injection. For loading control, membrane was reprobed with anti-GAPDH.