Fig. 3

PHH3 labeling identifies mitotic cells in the outer nuclear layer. a Combined PHH3 (red) and TUNEL (green) labeling in normal (A1, 6 wks), xlpra2 (A2, 8 wks), rcd1 (A3, 6 wks) and erd (A4, 11.6 wks) retinas at the peak of cell death for each disease [13]. There are no TUNEL or PHH3 labeled cells in the normal retina. In the mutants, some of the red (PHH3) and green (TUNEL) labeled nuclei in ONL are identified. Note that in erd (A4), two cells are undergoing combined proliferation and apoptosis (yellow arrows). b CD18 labeling (green) shows microglial cells and processes distributed primarily in the OPL and IPL, with increased expression in xlpra2 (B2), rcd1 (B3) and erd (B4) compared to normal (B1). PHH3 labeling in the mutants shows mitotic cells in ONL (red arrows). The two dividing cells in the OPL (B4, white arrows) are of unknown origin and are not counted in the analysis. c Glutamine synthetase (GS) labeling in normal (C1), and dual PHH3 and GS labeling in xlpra2 (C2), rcd1 (C3) and erd (C4). Dividing cells in ONL (red arrows) are not labeled with GS. Note that in xlpra2 and rcd1 there are PHH3-positive nuclei in the inner border of the INL (white arrowheads). d Confocal microscopy image of dual-immunolabeling of retinal sections with PHH3 (red) and rod opsin (green) in the ONL of xlpra2 (D1), rcd1 (D2), and erd (D3). The delocalized rod opsin associated with the cell membrane forms a green halo around the labeled nuclei. RPE = retinal pigment epithelium, ONL = outer nuclear layer, INL = inner nuclear layer, IPL = inner plexiform layer, NFL = nerve fiber layer. Scale bar: A-C = 40 μm; D = 5 μm