Previous studies in rats with STZ-induced type 1 diabetes show that antagonism of the leukocyte integrin, CD11b/CD18, using neutrophil inhibitory factor inhibits the formation of vascular lesions (Veenstra et al., 2013) and that genetic ablation of the CD18/ICAM interaction prevents leukostasis and reduces DR-associated retinal vascular pathology, including blood–retinal barrier breakdown, endothelial cell and pericyte loss, and the formation of acellular capillaries (Joussen et al., 2004). The gene discussed is ITGB2; the disease is type 1 diabetes mellitus.