TGF-Beta May Play a Role in Eosinophil-Stimulated VEGF Production by Conjunctival Fibroblasts

Abstract

Abstract: : Purpose: Vascular endothelial growth factor (VEGF) may be one of the factors involved in the fibrovascular growth that leads to the formation of giant papillae observed in severe ocular allergies. We reported previously that production of VEGF from cultured conjunctival fibroblasts was upregulated by eosinophil lysate (XV ICER, 2002). TGF-beta has been recently reported to induce VEGF production in bronchial fibroblasts. In this study, we investigated whether VEGF upregulation by eosinophil lysate from conjunctival fibroblasts is suppressed by anti-TGF–beta antibody. Methods: Conjunctival fibroblasts were cultured with eosinophils lysate and additional anti TGF-beta antibody in DMEM/F12 medium at 37°C for 24 hours. Concentrations of VEGF in supernatant were measured by ELISA. Results: The concentration of VEGF in supernatants stimulated with eosinophil lysate were 457.4±59.2 pg/ml, compared to 64.5±50.3 pg/ml in control (p<0.01). Anti-TGF-beta antibody downregulated the production of VEGF to 363.5±91.5 pg/ml (p<0.025). TGF-beta concentration in eosinophil lysate was not detectable. Conclusions: The results indicate that eosinophil lysates induce VEGF production from conjunctival fibroblasts through TGF-beta.

Keywords: conjunctivitis • inflammation • neovascularization