A gene set for the ‘immune response’ includes chemokine (C-C motif) ligand 2 (Ccl2), Ccl7, Ccl11, Cxcl1, interleukin 1B (Il1B), Il6 and interferon regulatory binding factor 8, indicating that inflammation may be a significant aspect in the dysfunction of β-cells in spontaneous T2DM GK rats. Here, CCL2 is linked to type 2 diabetes mellitus.