Targeted AAV gene therapy for neuroblastoma via direct capsid-antibody coupling

Adeno-associated viral (AAV) vectors are widely used in gene therapy for their versatility and safety, but their broad tropism limits cell-specific applications such as targeting primary or metastatic tumor cells. To address this, we developed AAV-STITCH, a strategy using SpyTag technology to covalently attach polypeptides to the AAV capsid. This allows precise, dose-dependent coupling of an anti-GD2 scFv to a galactose-binding-deficient AAV9-W503A capsid, redirecting tropism specifically to GD2-expressing neuroblastoma (NB) cells. In pseudometastatic xenograft mouse models, AAV-STITCHαGD2 selectively transduced NB tumor cells without transduction of healthy liver tissue. Furthermore, delivery of a suicide gene via AAV-STITCHαGD2 significantly slowed tumor growth and extended survival in mice with subcutaneous and pseudometastatic NB xenografts. When combined with standard-of-care chemotherapy for relapsed NB, AAV-STITCHαGD2 produced robust curative effects. Collectively, these results demonstrate the feasibility of engineering AAVs with highly specific transduction properties, providing a versatile platform for targeted tumor cell suppression and advancing the development of next-generation, precision gene therapies for cancer.