Figure 4.

Targeted Allele Suppression Using miRNA-Based Gene Therapy Rescues IHC Bundle Morphology in Tmc1^Bth/+ Mice

(A) Representative scanning electron microscopy images (top) of the organ of Corti of wild-type, Tmc1^Bth/+ untreated contralateral, and Tmc1^Bth/++AAV9.miTmc1 P15–P16 treated ears. The apical region (1.0 mm from the apical tip) of the organ of Corti was imaged at 20 weeks. High-magnification images (bottom) represent IHC hair bundles. Asterisk, arrow, and arrowheads indicate IHC loss and fully and partially fused stereocilia, respectively. (B) Low-magnification scanning electron micrograph illustrating the cochlea apical turn. The white box represents 1.0 mm from the apical turn and is represented in (A). (C) Quantitative comparison of hair cell counts per 100 μm of the apical region of the cochlea using scanning electron microscopy images in wild-type, Tmc1^Bth/+ untreated contralateral, and Tmc1^Bth/++AAV9.miTmc1 P15–P16 treated ears. Data are means ± SEM. Statistical analysis by Student’s t test: **p < 0.01.