Intra-ocular expression of vascular endothelial growth factor (VEGF) and pigment epithelial-derived factor (PEDF) in a case of Eales’ disease by immunohistochemical analysis: a case report

Abstract

We report a immunohistochemical study of expression of VEGF and PEDF in Eales' disease. An enucleated eye from a patient with Eales' disease and an age and sex-matched donor eyeball were subjected to immunohistochemical and histopathological analysis to study the expression of VEGF and PEDF in the retinal region. Strong positive anti-VEGF immunostaining was found around the vessel walls in the retina in the eyeball from the Eales' disease patient compared with the donor control, from which it was almost absent. PEDF staining was detected in the normal donor eyeball retinal layers surrounding the blood vessels, and the photoreceptor and ganglion cell layer, whereas in the eyeball from Eales' disease patient PEDF staining was restricted to the surrounding blood vessels. The strong expression of VEGF in eyes with Eales' disease as opposed to weak expression of PEDF indicates the propensity of the disease to show neovascularization and recurrent hemorrhages.

Vascular endothelial growth factor in the ischemic retina and its regulation by somatostatin

“…The extracellular VEGF may enter endothelial cells through receptor-mediated internalization; however, the elucidation of this mechanism will require further investigation. VEGF immunoreactivity in retinal vessels has been observed to increase in mouse models of oxygen-induced retinopathy (May et al 2006;Dal Monte et al 2007) or in the presence of retinal diseases characterized by neoangiogenesis (Lutty et al 1996;Mathews et al 1997;Cao et al 1999;Ellis et al 2000;Kim et al 2003;Verma et al 2010). In addition, internalization of VEGF mediated by VEGF receptor 2 has been reported in in vitro preparations of endothelial cells (Lampugnani et al 2006;Santos et al 2007;Chen et al 2010;Zhao et al 2010) as well as in the endothelium of tumor vessels (Falcon et al 2011).…”

Intravitreal bevacizumab as an adjunct to vitrectomy in advanced Eales’ disease

“…Massive expression of VEGF in the neovascular membranes in Eales’ disease has also been reported previously [6, 7]. Bevacizumab, a humanised monoclonal antibody against VEGF, is currently emerging as an effective off-label treatment for a variety of ocular disorders such as neovascular age-related macular degeneration, macular edema secondary to central retinal vein occlusion and proliferative diabetic retinopathy [8].…”

Eales’ disease: epidemiology, diagnostic and therapeutic concepts

“…Vitreous biochemical analysis showed significant increase in several growth factors, specially VEGF, in contrast to a PEDF reduction –a potent ischemia inhibitor [ 10 ]- and increased reactive substances, such as TBARS, and decreased E and C vitamins, superoxide dismutase, glutathione and glutathione peroxidase, suggesting oxidative stress [ 11 ].…”

“…Additionally, even though they share similar clinical and evolutionary characteristics, the behavior of Eales’ disease is less aggressive than that of proliferative diabetic retinopathy. We found this phenomenon even in cases with large areas of non-perfusion and/or aggressive neovascularization, probably because Eales’ pathology does not originate from a systemic metabolic disorder, or permanent endothelial dysfunction such as diabetic retinopathy [ 10 ].…”