C4B and diabetes mellitus: Our RNA-seq data showed many inflammation-associated genes with altered expression; these included C1q TNF-related gene 5 (C1qtnf5), latent TGF-β binding protein (Ltbp1), phospholipase (Pla2g2f), interleukin 17 receptor 7c (Il17rc), and C4b. The changes in relatively few transcripts of the inflammatory pathway by eight months of diabetes seen in our study, when compared to changes reported at shorter durations, might indicate that inflammation is most severe early during the etiology of diabetic retinopathy, and that its severity might diminish as the disease progresses.