Fig. 5.

Anc80L65–SaCas9–Htra2 gRNA injections protected hair cells and improved hearing function in neomycin-exposure mice. a Representative confocal microscopy images at 2 weeks after the last dose of neomycin from an injected cochlea and the contralateral (non-injected) cochlea. IHC inner hair cell, OHC outer hair cell. Arrows indicate the missing IHCs. Scale bar represents 20 μm long and applies to all images. b Quantification of the hair cells 2 weeks after the last dose of neomycin. Individual values are shown. Statistical tests in b are unpaired two-tailed Student’s t-tests. c ABR thresholds in injected and non-injected ears 2 weeks after the last dose of neomycin. Paired t-tests or Wilcoxon matched-pairs signed rank tests were used as applicable. d, e Peak amplitudes (d) and latencies (e) of ABR wave 1 evoked by 90 dB SPL at 4 and 8 kHz in the Anc80L65–SaCas9–Htra2 gRNA-injected ears compared with the non-injected ears 2 weeks after the last dose of neomycin. Unpaired two-tailed Student’s t-tests were used. f 8-kHz ABR waveforms recorded at 2 weeks after the last dose of neomycin from the representative non-injected ear and the single best injected ear. The hearing thresholds are shown in blue and red for the non-injected ear and injected ear, respectively. The scale bar applies to all traces. g ABR thresholds in injected and non-injected ears 4 weeks after the last dose of neomycin. Paired t-tests or Wilcoxon matched-pairs signed rank tests were used as applicable. The lighter red lines in c and g represent the ABR thresholds of individual injected ears. **p < 0.01, ***p < 0.001, ****p < 0.0001