Figure 7

LPS and hemin synergistically induce the production of LTB4 from human monocytes and Hx blocks this synergy by decreasing LTB4 levels and suppresses chemotaxis of neutrophils. (A) Human monocytes were incubated with LPS (10 µg/mL) in the presence or absence of hemin (1 µmol/L) for 1, 3 and 5 h. LTB4 concentrations in the supernatants were measured and compared between the cultures with LPS only and with LPS and hemin. (B) Human monocytes were incubated with LPS (10 µg/mL) and with or without hemin (1 µmol/L) in the absence or presence of hHx-B (1 mg/mL) for 3 h. LTB4 concentrations were measured and compared between the cultures with and without Hx. (C) The supernatants collected from human monocyte cultures at 3 h were loaded to the bottom microplate well of the transmigration system in chemotaxis assay. The percentage of neutrophils migrated to the bottom wells over the total cells loaded to the top of the transwells were calculated and compared between the cultures with and without hHx-B. The results are representative of three independent experiments and presented as the mean ± SE. **P < 0.01 LPS with hemin versus LPS only.