Vitreous concentrations of IL-6 and IL-8 were significantly greater in patients with PDR than in noninflammatory retinopathies, and serum TNF-α was significantly greater in PDR than in noninflammatory retinopathies (this latter finding was limited to the serum but did not hold true in the vitreous). This evidence concerns the gene CXCL8 and retinal disorder.