Figure 6: Effect of IRAK-1/4 inhibitor I on secreted MCP-1 levels in the culture supernatants of U373 cells, human astrocytes and human microglia after 6 hours incubation. (A) IL-1β (10 U/ml) induced MCP-1 secretion by U373 cells in the presence of IRAK inhibitor I (2500 nM). (B) IL-1β (10 U/ml) induced MCP-1 secretion by human primary astrocytes in the presence of IRAK inhibitor I (2500 nM). (C) LPS (1 μg/ml) induced MCP-1 secretion by human primary microglia in the presence of IRAK inhibitor I (2500 nM). Results are expressed as mean (± SD) of one representative experiment assayed in triplicate. Asterisks indicate significant difference compared with IL-1β or LPS treatment without IRAK inhibitor I treatment (p < 0.05).