Similar to TGF-β1, the AH TGF-β3 levels increased with the progression of DR (Table 2), resulting in a 1.8-fold increase in the concentration of TGF-β3 in patients with mild/moderate NPDR and a 3.8-fold increase in patients with advanced NPDR/PDR compared to the controls. Here, TGFB1 is linked to non-proliferative diabetic retinopathy.