Lipid-mediated gene transfer of acidic fibroblast growth factor into human corneal endothelial cells

The aim of this study was to optimize non-viral gene transfer conditions and investigate the effect of fibroblast growth factor-1 (FGF-1) gene transfer on human corneal endothelial cell (HCEC) proliferation. Five non-viral vectors (Lipofectin, DMRIE-C, DAC-30, Effectene, FuGene6) were used to transfect HCEC with plasmids coding for enhanced green fluorescent protein (EGFP) and FGF-1. Transfection efficiency and toxicity (n=6) were quantified and optimized using the EGFP construct by FACS-analysis. Using optimal conditions HCEC were transfected with the FGF-1 plasmid and cell proliferation as well as expression of FGF-1 were determined at days 4 and 7 by counting and western blotting, respectively. Lipofectin (17+/-2.02%) transfected HCEC more successfully than DMRIE-C (11+/-1.46%), Effectene (9+/-0.62%), FuGene (9+/-0.93%) and DAC-30 (7+/-0.59%). Toxicity of the lipids ranged from 2 to 4%. Optimal HCEC proliferation was achieved with DAC-30/FGF-1 (P<0.05), whereas all other vectors did not result in significantly increased cell proliferation. However, all of the transfected cells produced FGF-1 in different amounts as indicated by western blotting. Efficient and almost non-toxic transfer of the FGF-1 gene into HCEC can be successfully achieved by lipid-based techniques. Using optimal conditions significantly increased cell proliferation was independent on gene transfer efficiency. This may indicate that even a low transfection rate is sufficient to produce a concentration of FGF-1 that will have a stimulatory effect on HCECs.