Figure 3.

PGE₂ inhibits phagocytosis via the EP2 receptor–dependent signaling pathway. A: Macrophages isolated from normal women were treated with vehicle (Con), anti-CD36, PGE₂ (1 μM), or PGE₂ plus EP2 antagonist (AH6809, 10 μM) for 24 hr, and fluorescence intensity was determined by flow cytometry. M0: no bead was ingested; M1: with at least one bead ingested. B: Mean and SD of M1 obtained from four experiments using different batches of cells. C: Representative confocal microscopic images of phagocytic macrophages isolated from normal patients. Macrophages were treated with vehicle (Con), PGE₂, or PGE₂+AH6809 and then incubated with FITC-conjugated beads for 1 h. D: Mean and SD of the number of beads phagocytosed by macrophages isolated from normal women after treatment with vehicle (Con), PGE₂, or PGE₂+AH6809. Four independent experiments using different batches of macrophages were conducted, and at least 20 cells per experiment were counted. *P < 0.05, **P < 0.01, ***P < 0.001.