DEVELOPING NOSE-TO-BRAIN DELIVERY OF AAV2-MEDIATED GENE-THERAPY FOR NEURODEGENERATIVE DISEASES

Recombinant adeno-associated viral vectors (rAAVs) are a leading platform for gene therapy due to their safety and low immunogenicity. Diverse serotypes and engineered variants, combined with different administration routes, enable broad therapeutic applications. Parkinson’s disease (PD), the second most common neurodegenerative disorder, lacks disease-modifying therapies. AAV-mediated gene therapy offers new therapeutic approaches, but efficient neuronal transduction across the blood-brain barrier remains challenging. This study aims to identify an engineered AAV2 capsid variant with enhanced neuronal transduction via a minimal invasive delivery route.
Ten AAV2 variants tagged with GFP were screened in neuronal cultures of 3 days old wildtype and Thy1-αSyn mice, a PD model overexpressing human α-synuclein. Cultures were infected with three doses (500, 10,000, 25,000 genome copies). Transduction efficacy and cell-type specificity were assessed by GFP expression and immunofluorescent staining for neuronal markers like MAP2 and parvalbumin. Preliminary results indicate the necessity of high doses, with 6/10 variants yielding strong neuronal GFP signal at 25,000 genome copies. Cell viability was not affected, proving safety of AAVs. Thy1-aSyn mice will receive the variant with optimal neuronal specificity and minimal glial expression for in vivo proof-of-concept. The mice will receive the AAV2 variant via intravenous or intranasal application as possible minimal invasive delivery routes. Brains will be analysed 14 days post-injection for GFP expression and inflammatory markers.
In conclusion, we identify a promising AAV2 variant for neuronal targeting and aim to further evaluate nose-to-brain delivery in PD models opening possibilities for new therapeutical approaches in gene therapy.