PBMC (a, b) or MVEC (c, d) were untreated (control), or treated with the indicated concentrations of HMW or LMW (tri) adiponectin for 16 hours. Supernatants were harvested and supernatant concentrations of MCP-1 or IL-8 were measured by specific ELISA. Each figure is representative of 3–5 independent experiments done in triplicate. Using PBMC, HMW adiponectin significantly increased MCP-1 and IL-8 compared to control at concentrations of 0.1 and 1μg/ml (*P < 0.001). LMW adiponectin did not increase MCP-1 or IL-8 production by PBMC at any concentration tested. Using MVEC, HMW adiponectin significantly increased MCP-1 compared to control at concentrations of 5 μg/ml (**P < 0.01), 10 and 20 μg/ml (*P < 0.001), and increased IL-8 compared to control at concentrations of 5, 10 and 20 μg/ml (*P < 0.001). LMW adiponectin did not increase MCP-1 or IL-8 production by MVEC at any concentration.