Evaluation of risks related to the use of adeno-associated virus-based vectors.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing preclinical mechanisms, animal studies, and early human clinical observations.
PubMed 14683451 · doi:10.2174/1566523034578131
What was done
This review evaluates the biosafety profile of wild-type and recombinant adeno-associated virus (rAAV) vectors. It examines preclinical cell culture and non-human primate biodistribution studies as well as early human trial data to assess vector integration, insertional mutagenesis, viral shedding, germline transmission risks, and immune responses.
What was found
Wild-type AAV integrates site-specifically into chromosome 19 in approximately 60% of latently infected cell lines at high multiplicity of infection, though only approximately 1 in 1000 infectious units integrates. Because rAAV vectors lack Rep proteins, site-specific integration does not occur; episomal concatemers predominate, making random integration rare in vivo. Non-human primate biodistribution showed low, transient vector DNA in distal organs. In patients, rAAV was transiently detected in urine, saliva, serum, and semen (following hepatic artery administration), but motile germ cells appeared refractory to infection. Viral capsids elicited antibody responses without significant inflammation, whereas expressed transgene products elicited both humoral and cellular immunity depending on the protein and route.
Why it matters
This synthesis established early clinical safety parameters for rAAV gene delivery, supporting its low oncogenic and germline risk while highlighting transgene-directed immunogenicity and vector purity as key translational concerns.
Limits
The paper is a narrative review without systematic search or pooling methodology. Specific sample sizes, effect sizes, statistical intervals, and long-term human outcome data are not provided in the abstract.
Cited by
- supports Adeno-associated virus (AAV) vector DNA does not integrate into human chromosomes in over 90% of cases, instead forming an episome.