CCL2 and acute respiratory distress syndrome: In this study, we found that elevations in IL-6, IL-8, IL-10, MCP-1, and PAI-1 serum levels were common features in patients with sepsis, ARDS, or burns and that the serum IL-6 level was positively correlated with the serum levels of other cytokines and of PAI-1 in CRS patients.