Prevalence of Serum IgG and Neutralizing Factors Against Adeno-Associated Virus (AAV) Types 1, 2, 5, 6, 8, and 9 in the Healthy Population: Implications for Gene Therapy Using AAV Vectors

Antibodies to AAV following natural infections in humans may hamper AAV gene therapy approaches due to antibody mediated neutralization of the vector. The prevalence and characterization of the IgG subclass in 226 French subjects aged 25 to 64 years was tested. Results demonstrated substantial IgG1 prevalence of most serotypes indicative of the crossreactivity of sera to multiple serotypes in the human population.