CXCL8 and diabetes mellitus: Additionally, the level of the inflamamtory cytokine IL-8 was up-regulated in the PDR patients (101.49±79.04 pg/ml) in comparison to the control (39.99±53.25 pg/ml; p = 0.018) and the NPDR (20.67±9.43 pg/ml; p = 0.034) but not the DM patients (82.59±107.41 pg/ml; p = 0858; Fig 2B).