These experiments were designed to evaluate the interactions of vascular endothelial growth factor (VEGF), pigment-epithelium derived factor (PEDF), and sFlt1, each overexpressed in hfRPE, on their mRNA and protein levels.Confluent primary human fetal RPE cells were infected with AAV-VEGF, AAV-PEDF or AAV-sFlt1 with AAV-GFP as control.VEGF mRNA increased 2, 4, or 270 fold in hfRPE infected with AAV-PEDF, AAV-sFlt1, or AAV-VEGF, respectively. Apical VEGF decreased 20%-40% (p<0.05) in AAV-sFlt1 infected cells and increased 2-3 times (p<0.05) in AAV-VEGF infected cells while basolateral VEGF did not change significantly in both groups. In AAV-PEDF infected cells, VEGF protein did not significantly change in either the apical or basal compartments. In hfRPE infected with AAV-PEDF, AAV-sFlt1, or AAV-VEGF, PEDF mRNA increased 6, 2, or 2 fold, respectively. In hfRPE infected with AAV-sFlt1, the sFlt1 protein increased more than 100-fold in the apical compartment and more than 10-fold in the basal compartment (n= 2). The sFlt1 protein increased in AAV-VEGF infected samples and decreased in AAV-PEDF infected samples. These results suggest that in disease states angiogenic and anti-angiogenic factors secreted by the RPE may differentially affect blood vessel proliferation in the extracellular spaces on the retinal and choroidal sides of the tissue.
