Background/Aims To investigate the difference between human umbilical vein endothelial cells (HUVEC) and human ocular microvascular endothelial cell (MVEC) gene expression, and to determine if these differences could improve the understanding of ocular angiogenic diseases.

Methods The gene expression profiles of HUVEC and matched unpassaged human choroidal, retinal and iris endothelial cells were conducted using Affymetrix GeneChip Human Genome U133 Plus 2.0 arrays. Selected differences were confirmed by real time PCR. Functional cell proliferation assays were used to support microarray findings.

Results HUVEC showed enrichment for probe sets involved in embryological development while ocular MVEC demonstrated enrichment for probe sets for MHC classes I and II, immune responses and cell signal transduction. Comparison of human retinal and choroidal endothelial cells demonstrated significant differences in the expression of probe sets encoding insulin-like growth factor 1 (IGF-1) signalling. Cell proliferation assays demonstrated the stimulatory role of IGF-1 on retinal endothelial cells compared with choroidal endothelial cells.

Conclusions Gene expression profiling has demonstrated that HUVEC are probably not a suitable surrogate for the study of ocular angiogenic disorders. There are also significant differences in the gene expression of human retinal and choroidal endothelial cells, which may be important in the mechanism and treatment of choroidal and retinal neovascularisation.