Abstract
Purpose: :
Interleukin 10 (IL-10) has been identified as a potent pro-angiogenic factor in various forms of neovascularization. In the eye, it has been shown that IL-10 mediates angiogenesis in mouse models of oxygen-induced retinopathy and laser-induced choroidal neovascular membranes (CNVM). While many inflammatory mediators have been implicated in the pathogenesis of CNVM, to date, the expression of IL-10 has not been studied in human specimens. The purpose of this study was to investigate the expression of IL-10 in human CNVMs secondary to Age-Related Macular Degeneration (ARMD).
Methods: :
Ten cases of surgically-excised human CNVMs were used in this study (8 females and 2 males; age-range 60-80 years). All membranes were subjected to immunohistochemical analysis using a rabbit anti-human polyclonal antibody to IL-10 (ab34843, Abcam Inc.). The expression of IL-10 was graded as positive or negative in the retinal pigment epithelial (RPE), stromal and vascular endothelial cells in each specimen. Sections of human tonsil and colorectal cancer were used as positive controls.
Results: :
IL-10 expression was seen in seven of the ten membranes (70%).Six of the membranes showed expression in RPE cells, of which two additionally showed expression in vascular endothelial cells and one in stromal cells. One membrane expressed IL-10 in vascular endothelial cells only. No correlation was seen between expression of IL-10 and patient age or gender.
Conclusions: :
IL-10 was expressed in 70% of the CNVMs in this study. These results, coupled with previous animal model data, highlight a role for IL-10 in the pathogenesis of human CNVM. Further studies are warranted to investigate the efficacy of therapeutically targeting IL-10 in ARMD.
Keywords: age-related macular degeneration • choroid: neovascularization • immunohistochemistry