PS-containing liposomes enhance efferocytosis of X-CGD MØs in an IL-4–dependent manner. (A) PBS, PS, or PC liposomes were injected intraperitoneally for 24 hours and in vivo efferocytosis assay was performed as in “Efferocytosis assay.” Data represent means plus or minus SEM; N = 6 experiments. *P ≤ .005 compared with PBS-treated X-CGD. (B) After identical treatment, freshly isolated F4/80-positive MØs were analyzed for intracellular IL-4 by flow cytometry. Data represent means plus or minus SEM; N = 3 experiments. #P ≤ .005 compared with PBS-treated X-CGD. (C) After in vivo treatment as in panel A, RPMØs were plated in the presence or absence of neutralizing antibody to IL-4 (500 ng/mL) ex vivo for 24 hours and efferocytosis assays performed. Data represent means plus or minus SEM; N = 5 experiments. *P ≤ .005 compared with PBS-treated X-CGD; #P ≤ .005 compared with PS-treated X-CGD. (D) After in vivo treatment as in panel A, RPMØs were analyzed for surface receptors by flow cytometry; histograms are representative of N = 3 experiments.