Figure 2. Immunocytochemistry was performed to ensure retinal pigment epithelium (RPE) identity of the isolated cells. A: A large population of RPE65-positive cells (almost all) in early primary cultures confirmed the RPE origin of the isolated cells. C: The nuclei of RPE cells in (A) were stained with : 4´,6-diamidino-2- phenylindole dihydrochloride (DAPI). B: The RPE cells were immunostained for cytokeratin 8/18, confirming the epithelial identity of the isolated cells. D: The nuclei of RPE cells in (B) were stained with DAPI. E,F: As negative controls, RPE cultures were simultaneously immunostained without using primary antibodies. G,H: The DAPI-stained nuclei of RPE cells in control cultures.