Retinal pigment epithelial cells
Retinal Pigment Epithelial (RPE) cells exist in a layer outside of the retina that functions to protect, nurse and support the cells of the retina that are needed for normal vision. RPE cells protect the retinal cells by absorbing excess light and reducing damaging oxidizing agents. They also provide nutrients, balance the ion concentrations, clean up waste products and provide a critical barrier between the immune system and the interior of the eye. When RPE cells are lost due to disease an individual can suffer from the blinding disease called Age-Related Macular Degeneration (AMD). AMD is the leading cause of blindness in people over the age of 50. BioTime’s subsidiary Cell Cure Neurosciences is currently conducting clinical trials using their product OpRegen®, composed of stem cell-derived RPE cells to replace those lost by patients suffering from AMD.