Targeted AAV6 gene therapy restores corneal endothelial function in three hereditary corneal dystrophies

The corneal endothelium maintains corneal transparency and vision. Hereditary corneal dystrophies, including macular corneal dystrophy (MCD), Fuchs endothelial corneal dystrophy (FECD), and congenital hereditary endothelial dystrophy (CHED), cause progressive endothelial dysfunction, for which corneal transplantation is currently the main treatment. We evaluate an adeno-associated virus (AAV)-based gene therapy approach in preclinical models of MCD, FECD, and CHED. A refined intracameral injection method enables uniform endothelial transduction without corneal puncture. A single AAV6 administration supports sustained transgene expression in the corneal endothelium for over 18 months without detectable adverse immune responses. In MCD mice, AAV6-Chst5 reduces corneal opacification and restores keratan sulfate levels. In FECD mice, AAV6-Col8a2 prevents corneal opacity in 87.5% of treated eyes. In the CHED model, AAV6-Slc4a11 resolves corneal edema within 7 days. Single-cell RNA sequencing identifies Wnt5a as a downstream factor associated with MCD pathogenesis. These findings support the therapeutic potential of endothelial-targeted gene delivery for corneal endothelial disorders.