C. Schematic diagram of the granulocyte-macrophage colony-stimulating factor (GM-CSF)/interleukin (IL)-4-induced mouse monocyte DCs/macrophages differentiation assay. Cells were treated with specific antagonists of distinct EP receptors: ONO-8711, EP1; PF-04418948, EP2; L-798106, EP3; and E7046, EP4. 