Cells in CE neurospheres display retinal progenitor properties. Adult CE cells were cultured in the presence of mitogens to generate neurospheres and the acquisition of retinal properties was examined. RT-PCR revealed that the levels of CE-specific transcripts (Tyrosinase, Palmdelphin, and Rab27) decreased in neurospheres with the time (lane 1 = untreated CE cells, lane 2 = 3 days old neurospheres, lane 3 = 6 days old neurospheres). In contrast, cell proliferation-(Ki67 and Cyclin D1,) and retinal progenitor (Otx2, Lhx2 and Pax6)-specific transcript levels increased temporally in neurospheres (A). Q-PCR analysis corroborated the decrease in the levels of Palmdelphin, and Rab27 transcripts and detected Rx transcripts in neurospheres (B ). Immunofluorescence analysis revealed that cells in CE neurospheres were immunoreactive for Rx (D, E, F) and Pax6 (H, I, J) as retinal progenitors in E14 retina (C and G). Scale = 50 μm.