Novel AAV serotypes for improved ocular gene transfer

Some of the most successful gene therapy results have been obtained using recombinant viral vectors to treat animal models of inherited and acquired ocular diseases. Clinical trials using adenovirus vector systems have been initiated for two ocular diseases. Adeno-associated viruses (AAVs) represent an attractive alternative to adenoviral vector systems as they enable stable and long-term expression and can target a variety of different ocular cell types depending on the capsid serotype; recently clinical trails for congenital blindness was initiated with a vector-based AAV serotype 2. High levels of retinal gene transfer have been achieved using vectors based on AAV serotypes 1, 2, 4 and 5. This report compares the gene transfer efficacy and stability of expression of vector systems based on three novel AAV serotypes: AAV7, 8, 9, with the established vectors AAV1, 2, 5. We show here that AAV7 and 8 enable superior long-term transduction of retinal and also anterior chamber structures.