Table 1. Microsurgical injections and transduction efficiencies.
| P0 post-ex utero injections | E12–12.5 trans-uterine injections | Average hair cell transduction efficiency of AAV2/1 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Dams | Live pups | Infected hair cells | Dams | Live pups at 5 weeks | Infected hair cells | IHCs | OHCs | ||
| AAV2/1 | 5 | 16 (72%) | +++ | 6 | 1 7 (63%) | ++++ | Total | 81.42% | 64.03% |
| AAV2/2 | 0 | NA | N/A | 2 | 9 (100%) | + | Apical turn | 82.54% | 63.70% |
| AAV2/5 | 2 | 7 (78%) | – | Basal turn | 79.40% | 64.67% | |||
| AAV2/6 | 2 | 7 (78%) | – | ||||||
| AAV2/7 | 2 | 10 (100%) | – | ||||||
| AAV2/8 | 4 | 6(31%) | +++ | 6 | 21 (78%) | + | |||
| AAV2/9 | 2 | 4 (44%) | – | ||||||
| Lentivirus | 3 | 10(71%) | + | 5 | 1 3 (59%) | ++ | |||
Listed are the numbers of pregnant dams operated on and the subsequent numbers of live pups born that had been injected with each viral serotype. Numbers in parentheses indicate the percentages of injected fetuses that survived birth. On the first postnatal day qualitative assessments of the rate of hair cell infectivity, demonstrated by eGFP expression, were made. (+++) Highest infectivity rates. (–) No infectivity. Based on these data, trans-uterine microinjections of selected AAV serotypes and lentivirus were performed for longer term studies. Shown in the middle columns are the numbers of pregnant dams operated on and numbers of live injected pups from those dams after 5 weeks. Qualitative assessment of hair cell infection was again noted. Of the pups infected with AAV2/1, whole mounts were made of the apical and basal cochlear turns for hair cell counting to assess viral transduction efficiency.