AAV-DJ is Superior to AAV9 for Targeting Brain and Spinal Cord, and De-Targeting Liver Across Multiple Delivery Routes in Mice

Abstract

Highly efficient adeno associated viruses (AAVs) targeting the central nervous system (CNS) are needed to deliver safe and effective therapies for inherited neurological disorders. The goal of this study was to compare the organ-specific transduction efficiencies of two AAV capsids across three different delivery routes. We compared AAV9-CBA-fLucYFP to AAV-DJ-CBA-fLucYFP using the following delivery routes in mice: intracerebroventricular (ICV) 1x1012 vg/kg, intrathecal (IT) 1x1012 vg/kg, and intravenous (IV) 1x1013 vg/kg body weight. Our evaluations revealed that following ICV and IT administrations, AAV-DJ demonstrated significantly increased vector genome (vg) uptake throughout the CNS as compared to AAV9. Through the IV route, AAV9 demonstrated significantly increased vg uptake in the CNS. However, significantly fewer vgs were detected in the off-target organs (kidney and liver) following administration of AAV-DJ using the IT and IV delivery routes as compared to AAV9. Distributions of vgs correlate well with transgene transcript levels, luciferase enzyme activities, and immunofluorescence detection of YFP. Overall, between the two vectors, AAV-DJ resulted in better targeting and expression in CNS tissues paired with de-targeting and reduced expression in liver and kidneys. Our findings support further examination of AAV-DJ as a gene therapy capsid for the treatment of neurological disorders.