title: The prevalence of neutralizing antibodies against AAV serotype 1 in healthy subjects in China: implications for gene therapy and vaccines using AAV1 vector.
abstract: Recombinant adeno-associated virus serotype 1 (AAV1) has attracted tremendous interest as a promising vector for gene therapy and vaccine applications. However, the presence of AAV1 neutralizing antibodies as a consequence of exposure to wild type AAV1 can limit significantly effective gene transfer for biologics based AAV1 vector. Prior studies have reported that a prevalence of AAV1 neutralizing antibodies ranged from 10% to 50% in different countries around the world, and up to 79% in Dutch subjects. However, few studies have reported on the AAV1 neutralizing antibody prevalence in Chinese subjects. In this study, a high-throughput luciferase-based virus neutralization assay was established and standardized for critical parameters, including the appropriate cell line, and the optimal viral infection dose, and the infection time with homologous AAV1 vaccinated mice and guinea pig sera. Then, a total of 500 healthy individual serum samples from two separate regions of China were screened for the AAV1 neutralizing antibodies by conducting a non-randomized, cross-sectional analysis. Interestingly, a high prevalence of AAV1 neutralizing antibody (69.8%) was found in all individuals. There was significant difference observed for prevalence by gender (P = 0.042), age range (P = 0.011) and geographic origin (P < 0.001). The percentage of positive AAV1 neutralizing antibodies (NT50  > 10) in teenagers (year <18, as of 2012) was significant lower than that of adults (19-56, as of 2012) (P = 0.011), indicating the optimal vaccination period of childhood. The current study provides a useful insight for the future development of AAV1-based vaccination and gene therapy strategies in Beijing and Anhui provinces of China.
authors.affiliation: Department of Cell Biology, National Institutes for Food and Drug Control, Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products, Beijing, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Weijin
authors.initials: W
authors.lastname: Huang
authors.forename: Chenyan
authors.initials: C
authors.lastname: Zhao
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Shufang
authors.initials: S
authors.lastname: Meng
authors.forename: Dongying
authors.initials: D
authors.lastname: Gao
authors.forename: Youchun
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D057134:Antibodies, Neutralizing / Q000097:blood*; D000914:Antibodies, Viral / Q000097:blood*; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D000229:Dependovirus / Q000276:immunology*; D004337:Drug Carriers; D005260:Female; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors; D006801:Humans; D008297:Male; D008875:Middle Aged; D010322:Parvoviridae Infections / Q000453:epidemiology* / Q000276:immunology; D016036:Seroepidemiologic Studies; D014611:Vaccination / Q000379:methods; D055815:Young Adult
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D004337:Drug Carriers
keywords: AAV1; gene therapy; neutralizing antibody; vaccine