Abstract
Purpose: :
To determine the effect of pigment epithelium–derived factor (PEDF) modified iris pigment epithelium and retinal pigment epithelium in an in vitro model of choroidal neovascularization.
Methods: :
The isolation of human choroidal endothelial cells (CECs) using micro dissection followed by the use of superparamagnetic beads (Dynabeads) coated with the CD 31 antibody, which selectively binds to the endothelial cell surface. PEDF gene was transfected into IPE and RPE cells by lipofatamine 2000. The PEDF expressing IPE and RPE were cocultured with CECs. The mitogenic and motogeneic effects of VEGF on cultured choroidal capillary endothelial cells were examined in the presence or absence of PEDF gene modified epitheliua using cell counts and migration assays. The effects on CNV were tested using forming capillary structure analysis.
Results: :
Cells bound to beads are isolated using a magnetic particle concentrator. Isolated cells grew to confluence in a monolayer with a cobblestone morphology and were shown to be endothelial cells by their greater than 95% immunoreactivity to von Willebrand factor. Isolated cells grew as tubes in three–dimensional cultures. PEDF and PEDF expressing cells suppressed VEGF–induced retinal microvascular endothelial cell proliferation and VEGF–induced migration. The CNV models in vitro were also be suppressed. While it has no effect on normal choroidal endothelial cells.
Conclusions: :
PEDF and PEDF modified cells can inhibit VEGF–induced choroidal endothelial cell growth, migration and neovascularization. These findings suggest that transplantation of PEDF modified IPE cells may be an effective approach for the treatment of choroidal neovascular disorders.
Keywords: choroid: neovascularization • gene transfer/gene therapy • retinal pigment epithelium