Figure 5

AAV2.7m8 is capable of transducing IHCs and OHCs in the adult mouse cochlea, and the transduction efficiency increased in a dose-dependent manner. (a, b) Representative 10 × and 40 × images from apical, middle, and basal turns of the cochlea of mice injected with 1 µl (a) and 2 µl (b) of AAV2.7m8-GFP via the PSC approach. The IHC and OHC transduction rates are better in the animal that received 2 µl of AAV2.7m8-GFP gene delivery, as evidenced by higher number of IHCs and OHCs with GFP expression. (c) Quantitative comparison of transduction efficiency of IHCs and OHCs in adult mice that received 1 µl and 2 µl injections revealed a dose-dependent increase in hair cell transduction efficiency, especially in IHCs of the basal turn and OHCs of the apical turn (p < 0.05; t test). GFP expression is shown in green and Myo7a expression is shown in red. Scale bar represents 100 μm and 20 μm in 10X images and 40X images, respectively. For each animal, hair cell transduction rate was quantified at six different locations along the cochlea: two in the apical turn, two in the middle turn, and two in the basal turn. Data are represented as mean ± SEM). Statistical significance between groups is shown above error bars (*represents p < 0.05; t test).