Abstract
Purpose::
Choroidal neovascular membranes (CNV) excised from humans have been shown to contain growth factors and cytokines such as VEGF, FGF 2, IGF 1, PDGF and IL 1beta. Based on clinical observation the effect of VEGF in stimulating the growth of CNV in humans is undisputed, however it is likely that other growth factors also play a role. We have examined the effect of the previously mentioned growth factors on human choroidal endothelial cells (CECs) in both proliferation and angiogenesis assays to determine their potential role in CNV growth in humans.
Methods::
Human CECs were prepared and cultured in EBM2 MV medium as previously described. The proliferation of first passage human CECs after exposure to VEGF165, FGF2, IGF 1, PDGF-BB and IL-1Beta over the range of 1000 to 7.8 pmol/l, for 48 hours was measured by WST-1 assay and confirmed by a manual cell counting technique. The effect of the growth factors on angiogenesis was assessed on first passage human CECs by sprout formation in a double layer Matigel technique.
Results::
The growth factors at a concentration of 1000 pmol/l produced the following increases in proliferation compared to a serum reduced control: VEGF - 180%, FGF 2 - 150%, VEGF/FGF2 - 300%, IGF1 - 10%, PDGF BB - 15%, IL-1Beta - 10%. The growth factors at a concentration of 1000pmol/l produced the following increases in sprout formation compared with serum reduced control in the Matrigel double layer assay: VEGF - 160%, FGF 2 - 140%, VEGF/FGF2 240%, IGF1 - 30%, PDGF BB - 20%, IL-1Beta - 0%.
Conclusions::
Both VEGF and FGF2 appear to significantly increase the proliferation and sprout formation of first passage human CECs. The combined effect of VEGF and FGF2 also appears to be appears to be additive. The growth factors: IGF1, PDGF BB and IL-1beta do not appear to significantly alter the growth of human CECs in primary culture. These results suggest that targeting other growth factors such as FGF2 in addition to VEGF, may have beneficial effect in the treatment of human CNV.
Keywords: age-related macular degeneration • choroid: neovascularization