Retinal Pigment Epithelium Culture;a Potential Source of Retinal Stem Cells

Purpose: To establish human retinal pigment epithelial (RPE) cell culture as a source forcell replacement therapy in ocular diseases.Methods: Human cadaver globes were used to isolate RPE cells. Each globe was cut intoseveral pieces of a few millimeters in size. After removing the sclera and choroid,remaining tissues were washed in phosphate buffer saline and RPE cells were isolatedusing dispase enzyme solution and cultured in Dulbecco’s Modified Eagle’s Medium:Nutrient Mixture F-12 supplemented with 10% fetal calf serum.Results: Primary cultures of RPE cells were established and spheroid colonies related toprogenitor/stem cells developed in a number of cultures. The colonies included purelypigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages,several types of photoreceptors and neural-like cells were detected morphologically.Conclusion: Cellular plasticity in RPE cell cultures revealed promising results in termsof generation of stem/progenitor cells from human RPE cells. Whether the spheroidsand neural-like retinal cells were directly derived from retinal stem cells or offspring oftrans-differentiating or de-differentiating RPE cells remains to be answered