Adult-Human Retinal Pigment Epithelial Cell Transplantation Supports Retinal Function in Non-Human Primate Models

While recent trials of retinal pigment epithelium (RPE) transplantation for advanced age-related macular degeneration (AMD) treatment have been promising, the existing strategies still have limitations including the uncertain survival of RPE cells delivered by cell suspension and the risk of uncontrolled cell proliferation in the vitreous cavity. Human cadaveric donor RPE cell (ahRPE) transplants have been shown to rescue vision in a rat model of retinal dystrophy and survive in the rabbit retina for at least 1 month, suggesting its suitability as an alternative cell resource. The present study placed an ahRPE monolayer under the macula of a non-human primate model for up to 3 months. It was able to mature in-vivo and support photoreceptor function. Most importantly, transplanted monolayers did not undergo epithelial-mesenchymal transition to form epiretinal membranes. Gliosis was suppressed in adjacent retina. These findings indicate the safety and potential of ahRPE monolayer as a cell replacement source.