Cells in CE neurospheres express RGC-specific regulatory and marker proteins. Immunofluorescence analysis of CE cells in the presence of E14CM for 5 days revealed a subset expressing immunoreactivities corresponding to RGC markers, Atoh7, RPF1 and Thy1, like RGC progenitors/precursors in E14 retina (A-C), the proportion of which was significantly higher, compared to controls (D). Calcium imaging by Fura2 revealed the mobilization of intracellular calcium in differentiated cells in the presence of NMDA agonist (NMDA+) and not in its absence (NMDA-), indicating the presence of ionotropic glutamate NMDA receptor expressed by RGCs in vivo (E). Bar illustrates fluorescence intensity in a pseudo-color scale (E). Controls: CE untreated cells. Scale = 50 μm.