Measurement and significance of serum tumor necrosis factor-α, interleukin-2 and intercellular adhesion molecule-1 in patients with diabetic retinopathy

Objective To determine the serum levels of tumor necrosis factor-α (TNF-α),interleukin-2 (IL-2) and intercellular adhesion molecule-1 (ICAM-1) in the patients with diabetic retinopathy and the healthy controls,and to explore the roles of these cytokines in the development of the diabetic retinopathy.Methods A series of 62 patients with diabetic retinopathy and 22 healthy persons from our hospital were investigated.The serum levels of TNF-α,IL-2 and ICAM-1 in both patients and controls were measured by the enzyme-linked immunosorbent assays.Results The serum levels of TNF-α in the patients with diabetic retinopathy were significantly higher than that of the healthy controls (F =9.797,P =0.003).The serum levels of IL-2 and ICAM-1 in the patients with diabetic retinopathy had no significant difference than that of the control group (F =2.215/0.096,P =0.144/0.758).The serum levels of IL-2 in the patients with non-proliferative diabetic retinopathy were significantly higher than that of the patients with proliferative diabetic retinopathy (F =10.926,P =0.003).The serum levels of TNF-α and ICAM-1 in the patients with non-proliferative diabetic retinopathy were not significantly higher than that of the patients with proliferative diabetic retinopathy (F =2.072/0.042,P =0.161/0.840).Conclusions The serum TNF-α and IL-2 are raised in the patients with diabetic retinopathy,it suggests that the TNF-α and IL-2 may play the important roles in the pathophysiology and progression of diabetic retinopathy. Key words: Diabetic retinopathy; Tumor necrosis factor-α; Interleukin-2; Intercellular adhesion molecule-1