To access the data, click or select the words “Appendix 2.” Morphology and identification of rat retinal pigment epithelium (RPE) cells. (A) Primary RPE cells (P0) were polygonal and contained abundant pigment granules. (B) Second-passage (P1) RPE cells were fibroblast-like. The pigment granules were less than at P0. (C) Third-passage RPE cells contained few pigment granules. (D) RPE cells were positive for CK3 by immunofluorescence. One cell contained pigment granules (arrow). (E, F) RPE cells were positive for RPE65 and S-100 by immunofluorescence.