Figure 4. Immunofluorescent labeling of GFAP (red) in retinal cryosections of wild-type (rd3^+/+) and rd3^−/− mouse. Labeling of GFAP is restricted to the Müller cells located at the inner limiting membrane of the retina in the wild-type mouse, whereas in the rd3 retina, the labeling expanded toward the outer nuclear layer. Abbreviations: RPE, retinal pigmented epithelium; OS/IS, outer segment/inner segment; ONL, outer nuclear layer; OPL, outer plexiform layer; INL, inner nuclear layer; IPL, inner plexiform layer; GCL, ganglion cell layer.