Similar to MCP-1, MDC, and MIP-4, GRO was also found to be important in our WTC-LI model and further revealed immune cell involvement in WTC-LI pathogenesis.[80] GRO—also relevant in acute and chronic lung inflammation such as fibrosis—is part of a chemokine receptor system that mediates neutrophil recruitment.[81–84] In addition, lipids are a diverse group of bioactive compounds that have been implicated in the development of lung disease. This evidence concerns the gene CCL18 and lung disorder.