Figure 2. Nestin expression in FIV-transduced retinal progenitor cells. A: Immunocytochemistry for nestin expression (red signal) in retinal progenitor cell (RPC) spheres cultured under proliferating conditions. The nuclei of all cells were stained with DAPI (blue signal) and analyzed using a Zeiss Axiovert 200 m fluorescence microscope. B: Quantitative analysis of nestin-positive cells in feline immunodeficiency virus (FIV) for yellow fluorescent protein (YFP)-infected and noninfected RPCs. The percentage of nestin-expressing cells was determined by counting at least 100 cells in three independent experiments. Results are expressed as mean±SEM; p<0.05 (Student’s t-test; FIV-YFP versus control).