Figure 4. RB116 cells express retinal stem cell/progenitor markers PAX6 and CHX10. RB116 cells were analyzed by immunocytochemistry, compared with Y79 and WERI-RB27 cells, and found to contain subpopulations of cells immunoreactive to PAX6 (9.8%) and CHX10 (1.2%). The (-) control received isotype control antibody instead of primary antibody. Experiments were repeated 3 times and three groups of 100 cells were counted for each cell type. Error bars indicate standard deviation. Tukey’s post tests were performed to calculate p values. For PAX6, WERI-RB27 is greater than (-) control (p<0.001), RB116 is greater than (-) control (p<0.01) and Y79 Is greater than (-)control (p<0.05). For CHX10, one way ANOVA did not reveal differences between cell types at p<0.05. For quantitative PCR (qPCR), Y79 expression was set at 1.0. Both PAX6 and CHX10 were detected by qPCR in three experiments. For PAX6, Y79 is greater than (-) control (p<0.05) and RB116 is greater than (-) control (p<0.01). For CHX10, one way ANOVA did not reveal differences between the RB cell types at p<0.05. GAPDH was used as a reference control gene.