Figure 3.

Elucidation of retinal photoreceptor degeneration in human retinitis pigmentosa patients and mouse rd1 mutants.

(A, B) Human and mouse ocular fundus photographs, OCT and electroretinograms are shown. (i) The ocular fundus photographs and OCT images of an adult human and C57BL/6 mouse retina is shown. (ii) The ocular fundus photographs and OCT images of an adult patient with RP and 3-month-old rd1 mouse retina is shown. The black arrow in the human fundus images and the green line in the mouse fundus images depict the location of the OCT scan across the macula. The fundus images of patient with retinitis pigmentosa, shows pigmentary changes with atrophic areas indicating degeneration of photoreceptors. The OCT images of RP patient shows marked thinning, reflecting loss of photoreceptors and degeneration. The fundus images of rd1 mouse retina shows atrophy, discoloration, and loss of blood vessels showing degenerating retina. The area in the red rectangle is magnified in the right image. (iii) Retinal functions in response to light stimulation were measured by ERG. In dark conditions (scotopic), a normal eye when exposed to dim or bright white light flash, either initiates a well-formed rod response (black wave, left panel) or a type of mixed rod/cone response (black wave, right panel). In light conditions (photopic), single light stimulation of the eye leads to a cone response (black wave, lower left panel), and rapid light stimulation results in flicker waveform (black wave, lower right panel). In RP patients and in rd1 mutant mouse, the electrophysiological responses are reduced or non-detectable (red traces). ERG: Electroretinography; OCT: optical coherence tomography; RP: retinitis pigmentosa. Reprinted from Veleri et al. (2015).