Time course decline of phagocytic capacity of peritoneal macrophages stimulated with lipopolysaccharide (LPS) and restored by the later addition of interferon (IFN)-β (1,500 U/ml). Peritoneal macrophages from normal mice were seeded at 8 × 105 cells/500 µl of Roswell Park Memorial Institute media with L-glutamate, 25 mM HEPES supplemented with 10% fetal bovine serum/well and incubated with LPS (10 ng/ml) for the indicated times. After the designated period of incubation, phagocytic capacity was evaluated by adding fluorescent latex beads for another 24 h. Fluorescent intensity of harvested cells was measured by flow cytometry. In some wells, IFNβ was added 12 h after LPS stimulation and incubated for a further 12 h. Horizontal bar, without LPS; open bar, stimulated with LPS for the indicated period; and closed bar, stimulated with LPS for 24 h and coincubation with IFNβ. Data are shown as the mean (±SD), and numbers (n) of mice included for each condition are indicated in parentheses.
