Figure 2. IL-6 concentrations in serum and AqH from patients with T2DM and non-diabetic controls. Interleukin-6 (IL-6) was measured with multiplex bead immunoassay in serum (A) and aqueous humor (AqH; B) from controls (n = 51), non-diabetic retinopathy (NDR, n = 47), nonproliferative diabetic retinopathy (NPDR, n = 52), and proliferative diabetic retinopathy (PDR, n = 53). All groups were compared using the Kruskal–Wallis test followed by the Dunn multiple comparison test. C: The relationship between IL-6 in AqH and serum was tested, when matched samples were available, with the Spearman correlation. *p<0.001.