Fig. 2. (A ) The concentrations of human prostaglandin E²(PGE²) and total PGE²in coincubation of human placental multipotent mesenchymal stromal cells (hPMSCs) and RAW264.7 cells with cell–cell contact. (B ) The concentrations of human PGE²and total PGE²in coincubation of hPMSCs and RAW264.7 cells without cell–cell contact. (C ) The concentrations of tumor necrosis factor-α, interleukin-6, macrophage inflammatory protein, intercellular adhesion molecule 1, prostaglandin E², and interleukin-10 in coincubation of hPMSCs and RAW264.7 cells with and without cell–cell contact as well as the interleukin-10 concentrations in the coincubation of hPMSCs and primary macrophages culture (PM) with and without cell–cell contact. Human placental MSCs were added to RAW264.7 cells or PM at 4 h before lipopolysaccharide (LPS) administration (cell number: hPMSCs vs.  RAW264.7 cells or PM = 1:10²). PBS+R is the RAW264.7 cells plus phosphate buffered saline group; PBS+R+S is the RAW264.7 cells plus hPMSCs plus phosphate buffered saline group; LPS+R is the RAW264.7 cells plus LPS (100 ng/ml) group; LPS+R+S is the RAW264.7 cells plus hPMSCs plus LPS group; LPS+PM is the PM plus LPS (100 ng/ml) group; LPS+PM+S is the PM plus hPMSCs plus LPS group. The concentrations of tumor necrosis factor-α, interleukin-6, macrophage inflammatory protein, intercellular adhesion molecule 1, prostaglandin E², and interleukin-10 were assayed using enzyme-linked immunosorbent assays. Data were derived from three independent experiments performed in duplicates (n = 6) and analyzed with one-way ANOVA with the Tukey test for post hoc  comparisons. Data were means ± standard deviations. *P < 0.05 versus  the PBS+R group. #P < 0.05 versus  the LPS+R group. §P < 0.05 the LPS+R+S group with cell–cell contact versus  the LPS+R+S group without cell–cell contact. ICAM-1 = intercellular adhesion molecule; IL = interleukin; LPS = lipopolysaccharide; MIP-2 = macrophage inflammatory protein; PBS = phosphate buffered saline; PGE²= prostaglandin E²; R = RAW264.7; S = human placental multipotent mesenchymal stromal cells, or hPMSCs; TNF-α = tumor necrosis factor-α.