Evaluation of Vitreal Stromal-Derived Factor 1 Levels in Patients With Retinal Vein Occlusion (RVO)

Abstract

Purpose:: To evaluate stromal-derived factor-1 (SDF-1), vascular endothelial growth factor (VEGF) and inflammatory cytokines in retinal vein occlusion (RVO).

Methods:: The vitreous samples of 20 RVO eyes were collected during vitrectomy. The amounts of SDF-1 levels and VEGF were measured by enzyme linked immunosorbent assay (ELISA). Inflammatory cytokines, interleukin (IL)-1b, IL-6, IL-8, IL-10, IL-12, and tumor necrosis factor-α, were quantified by cytometric bead array. The RVO eyes were classified into two groups, active RVO group (A-RVO group, iris neovascularization and/or traction retinal detachment; 4 eyes) and quiescent RVO group (Q-RVO group;16 patients), for statistical analysis. Nine eyes with epiretinal membrane were used as controls.

Results:: The A-RVO group had a mean SDF-1 concentration of 278.95 pg/ml, Q-RVO group had that of 61.18 pg/ml and control group had that of 37.32 pg/ml. SDF-1 concentration in A-RVO group was significantly higher than that in Q-RVO group (Mann-Whitney, P<0.01) and that in control group (P<0.01). But there was no significance between Q-RVO group and control group. Although there were similar significances in VEGF, IL-6 and IL-8 levels, the median VEGF and IL-8 concentrations in Q-RVO group were higher than that in control group (P<0.001). There was not any significant correlation between SDF-1 and other cytokines.

Conclusions:: Intravitreous VEGF and IL-8 levels were high both in quiescent and active RVO. In contrast, intravitreous SDF-1 level is not high in quiescent RVO, but increased high in active RVO. SDF-1 might play a central role in proliferative change of RVO.

Keywords: cytokines/chemokines • vitreous • retinal neovascularization