IFNG and diabetic retinopathy: In their experimental study, Nagineti et al demonstrated that inflammatory cytokines, including interleukin 1 beta (IL-1β), interferon gamma (IFN-γ) and TNF-α, increase the secretion of vascular endothelial growth factor (VEGF) A and C by human retinal pigment epithelial (RPE) cells and choroidal fibroblasts, with VEGF being the most important factor for initiating pathological ocular neovascularization.9 TNF-α appears to play a major role in the pathogenesis of diabetic retinopathy in rats, and its pharmacological blocking leads to the inhibition of retinal cell death.10