Figure 3.

AAV vectors transduced inner-ear cells in adult cochleae. Two weeks post injection through canalostomy, whole-mount immunofluorescence showed AAV infection in the sensory and non-sensory cells from the apical turn of the cochlea. Hair cells were labeled with MYO7A (red). AAV1 (A–C), AAV6.2 (D–F), and AAVrh.39 (G–I) infected mostly IHCs, with moderate expression level. OHCs were not transduced. (J–K) Adult cochlea infected by Ad5-CMV-GFP using the same procedure. Ad5-CMV-GFP injection killed most OHCs without infection of IHCs. Some non-HCs in the sensory region were GFP positive although their cell types were unknown. (M–O) An example of an uninjected cochlea in which no GFP was detected, whereas the contralateral cochlea was injected with AAVrh.43 that infected IHCs. Scale bars: 50 μm.