Correlations between inflammatory mediators and the phagocytic response induced by oAβ in fAβ-stimulated microglial phagocytosis. Primary microglia were pretreated with or without oAβ(1-42) (0.2, 1.0, 5.0 μM) for 12 h. The supernatant was collected to determine the levels of IL-1β, TNF-α, PGE2 and NO by ELISA, EIA and Griess analysis, respectively. On the phagocytosis assay, the cells were then treated with fAβ(1-42) (5.0 μM) for 30 min and incubated with fluorescent microspheres for another 30 min. Phagocytosis of the fluorescent microspheres was quantified as percent of phagocytic cells. Levels of IL-1β, TNF-α, PGE2 and NO were expressed as relative folds normalized to those of the control. Data are presented as the mean ± S.E. Pearson test was applied for the partial correlation analyses, P < 0.001.