IRIS PIGMENT-EPITHELIUM TRANSPLANTATION

Background: Iris pigment epithelium (IPE) cells and retinal pigment ep ithelium (RPE) cells possess the same embryonic origin. It is also kno wn that the pigmented epithelial cells in the eye have a high transdif ferentiation potential. In this study we transplanted IPE cells into t he subretinal space of albino Royal College of Surgeons (RCS) rats and evaluated their influence on the degeneration of the photoreceptors. Methods: IPE cells of Long Evans rats were isolated and pure cultures were obtained. The isolated cells were transplanted into the subretina l space of RCS rats. Light microscopic and morphometric analysis were carried out. Results: The IPE transplants survived in the subretinal s pace and attached themselves to the Bruch's membrane. The transplanted cells were able to delay the degeneration of the photoreceptors for u p to 3 months. Conclusion: These results suggest that IPE cells could be successfully transplanted and survive in the subretinal space. In t he transplanted eyes the photoreceptors were preserved for a period of 3 months. Further studies are needed to explore the capability of IPE cells to assume the main functions of RPE cells in the subretinal spa ce and their potential in the therapy of selective degenerative diseas es of the retina.