CCL2 and Renal insufficiency: In the same study, an in vitro experiment showed that IS induced the phosphorylation of Stat3 on tyrosine 705 and then increased the expression of inflammatory and fibrotic genes, such as TGF-β1, monocyte chemotactic protein-1 (MCP-1, a potent chemotactic factor for monocytes) and α-smooth muscle actin (α-SMA, an isoform of actin and marker of myofibroblasts) in human proximal tubular HK-2 cells, which are involved in renal inflammation and fibrosis, and may contribute to renal failure [70].