Figure 4 Figure 4. AAV2/2-mediated EGFP expression in the somas and axons of retinal ganglion cells. Intravitreal injections of AAV2/2-CMV-EGFP were performed 5-6 weeks prior to perfusion fixation. Representative fluorescence microscopy images of optic nerve axons in retinal flat mount and 20 ┬Ám thick longitudinal cryosections of optic nerves. Images captured at 100x (left and top right) and 200x (bottom right) magnification.