CCL2 and type 1 diabetes mellitus: With regard to the association between serum MCP-1 levels and T1DM, MCP-1 mRNA expression has been found increased in diabetic mice during the early phases of insulitis, as well as at later stages of diabetes, suggesting the possible involvement of β-cell-derived MCP-1 in the recruitment of mononuclear cells into pancreatic islets [45,46].