Figure 1. Fluorescence Microscopy GFP. Retinal flat mounts inoculated with scAAV-GFP revealed some green fluorescent protein (GFP) positive cells (A). Confocal microscopy revealed many more GFP positive cells by immunofluorescence (B). RGCs labeled with the Brn3a antibody (C) and merged images revealed GFP expressing cells co-localized exclusively with those expressing Brn3a (D). Higher power confocal micrographs of scAAV-GFP injected eyes show nuclei labeled by DAPI (E). Cells expressing GFP (F) or Thy1.2 (G) co-localized (H). Cryo-sectioned retinas of scAAV-GFP injected eyes counterstained with DAPI revealed the nuclei of cells in the retinal ganglion cell layer (RGC), inner nuclear layer (INL) or outer nuclear layer (ONL; I). GFP immunofluorescence is seen exclusively in the ganglion cell layer (J) whose RGCs were labeled by Thy1.2 (K). Colocalization of GFP and Thy1.2 cells is shown in the merged panel (L).