We recently reported that vitreous levels of IL-4, IL-17A, IL-22, IL-31, and TNFα in PDR patients were higher than the respective levels in serum, and that vitreous levels of these cytokines were higher in PDR than in idiopathic epiretinal membrane (ERM), macular hole (MH), or uveitis associated with sarcoidosis [18]. Here, IL4 is linked to uveitis.