Figure 9.

Preservation of cone function and cone proteins in Rp2-KO mice following vector treatment at an older age. (A) Light-adapted ERG b-wave amplitude of 18-month-old Rp2-KO mice that received subretinal injection of AAV8-scRK-hRP2 vector at 10 months of age. Mice were injected unilaterally with the vector at a dose of 3 × 10⁸ vg/eye, with the vehicle injected to the contralateral eyes as controls. The stimulus intensities were from −1.0 to 2.0 log cd s/m². Only the amplitude with the highest flash stimulus is shown. The ERG response with a full range of flash stimuli is shown in the Supplementary Material, Figure S10. The number of mice tested in each group is indicated by white lettering inside each bar. ERG amplitudes from vector- and vehicle-injected eyes were compared by two-tailed paired t-test and represented as mean ± SEM. **P < 0.01. The vector-injected eyes exhibited significantly higher amplitude than control eyes. (B) Representative light-adapted and 10 Hz flicker ERG traces. (C) Immunofluorescence of retinal sections. Higher numbers of S- and M-opsin expressing cells were maintained in the vector-treated retinal sections. Cone PDE6 (cPDE6) expression was also restored in the OS of the vector-treated retina. Scale bar 50 μm. OS, outer segments; IS, inner segments; ONL, outer nuclear layer; INL, inner nuclear layer.