The state of the cytokine profile of the vitreous body in proliferative diabetic retinopathy

Introduction: Proliferative diabetic retinopathy (PDR) is a severe complication of diabetes mellitus, in whose pathogenesis chronic inflammation and pathological angiogenesis play a key role. Studying the local cytokine profile of the vitreous body allows us to identify specific mediators involved in the development of the disease. Objective: To conduct a comparative analysis of the concentrations of a wide range of cytokines in the vitreous body of patients with PDR and in the control group to identify an imbalance of key mediators of inflammation and angiogenesis. Methods: The study analyzed vitreous samples obtained from nine patients with PDR and seven control patients (idiopathic epiretinal membranes). Cytokine concentrations were determined using a multiplex enzyme-linked immunosorbent assay (Bio-Plex Pro Human Cytokine 27-plex Assay). Statistical data processing was performed using GraphPad Prism software. The nonparametric Mann-Whitney U test was used to compare groups. Statistical significance was established at p < 0.05. Results: Patients with PDR showed statistically significant increases in concentrations of proinflammatory and proangiogenic mediators compared to the control group. The most pronounced increases were noted for IL-8 (6.7-fold), MCP-1 (3.2-fold), and eotaxin (2.3-fold). Levels of IL-6, IL-1β, IL-4, IL-13, IFN-γ, IL-12(p70), and the growth factors VEGF and PDGF-BB were also significantly increased. Conclusion: These data confirm the central role of local inflammation in the pathogenesis of PDR. The vitreous cytokine profile in PDR is a complex mixture of proinflammatory, proangiogenic, and regulatory signals. The results support the development of therapeutic strategies aimed not only at inhibiting angiogenesis (anti-VEGF therapy) but also at modulating the inflammatory component of the disease.