Adult Treatment Window STRC
All STRC preclinical work uses neonatal or young mice. Nobody has data on restoring adult OHCs with long-standing STRC deficiency.
In Strc-/- mice, stereocilia lose horizontal top connectors by postnatal day 15. Bundle stiffness drops 60-74%. The structural scaffold that stereocilin maintains just falls apart without the protein. And once stereocilia bundles degrade, it’s not clear whether adding stereocilin back can rebuild them.
The question for Misha (age 4 now): what happens to human OHCs without STRC over 4 years? Is there a point of no return where stereocilia damage becomes irreversible, and no amount of gene therapy can fix it?
The OTOF comparison is tempting but misleading. AK-OTOF restored hearing in an 11-year-old who’d been deaf for 10+ years. Incredible result. But OTOF affects synaptic vesicle release in inner hair cells. The hair cells themselves are structurally intact. You’re fixing a chemical problem, not a structural one. STRC is structural. The protein holds stereocilia bundles together. Different biology entirely.
The seronegative window adds time pressure. At age 4, roughly 90-95% of children are seronegative for common AAV serotypes. That number drops with age. Every year of delay reduces the probability that AAV-based treatment will work on the first attempt. You get one clean shot before the immune system learns to block the vector.
Two clocks running: structural degradation of stereocilia and narrowing of the immune window. Both argue for earliest possible intervention.
Connections
- STRC Gene Therapy — treatment timing is a critical variable
- STRC Variant c.4976A>C — Misha — directly relevant to Misha’s timeline
- STRC Anti-AAV Immune Response Model — seronegative window data
- OTOF Clinical Trials 2025 Dual-AAV Validation — OTOF adult recovery is not transferable to STRC
- STRC Gamma-Poisson Transduction Model — efficiency assumptions depend on structural integrity
- Prestin and OHC Electromotility — OHC function depends on stereocilia structure