Increased interleukin-26 expression in proliferative diabetic retinopathy

Area of Science:

• Ophthalmology
• Immunology
• Endocrinology

Background:

• Diabetic retinopathy (DR) is a microvascular complication of diabetes.
• The pathogenesis of DR involves complex inflammatory and angiogenic processes.
• The role of specific cytokines, such as interleukin-26 (IL-26), in DR remains unclear.

Purpose of the Study:

• To investigate the potential involvement of IL-26 in the pathogenesis of diabetic retinopathy.
• To compare IL-26 expression in different stages of DR: diabetes without retinopathy (DWR), non-proliferative diabetic retinopathy (NPDR), and proliferative diabetic retinopathy (PDR).

Main Methods:

• Serum and vitreous fluid samples were collected from DR patients and controls.
• Protein expression of IL-26 was quantified using enzyme-linked immunosorbent assay (ELISA).
• Messenger RNA (mRNA) levels of IL-26 in peripheral blood mononuclear cells (PBMCs) were assessed via real-time polymerase chain reaction (PCR).

Main Results:

• Serum IL-26 was significantly higher in the PDR group compared to normal controls, DWR, and NPDR groups.
• Vitreous fluid IL-26 concentration was elevated in PDR patients not receiving anti-VEGF therapy compared to controls.
• PBMC IL-26 mRNA levels were significantly increased in PDR patients compared to normal controls and DWR patients.

Conclusions:

• Both protein and mRNA expression of IL-26 are upregulated in PDR patients.
• These findings suggest a potential association between IL-26 and the pathogenesis of proliferative diabetic retinopathy.