Transcriptome Analysis and Molecular Signature of Human Retinal Pigment Epithelium

The retinal pigment epithelium (RPE) is a polarized cell layer that is critical for photoreceptor function and survival. It’s unique relationship to the photoreceptors and its specific physiology makes the RPE a critical determinant of human vision. Therefore we performed global expression profiling of native and cultured human fetal and adult RPE and determined a unique set of highly-expressed genes (called the “signature” set) by comparing the observed RPE gene profiles to the Novartis expression database (SymAtlas: http://wombat.gnf.org/index.html) of 78 tissues. A comparative analysis of transcriptomes from human fetal and adult RPE, primary cultures and commonly-used cell lines was performed. Using selection criteria of at least 10-fold higher expression in each of three RPE preparations, we identified 154 RPE signature genes, which were validated by qRT-PCR analysis in RPE and in an independent set of 11 tissues.