Genome Integration of Adeno-associated Virus (AAV) Vectors into Infected Cells

The development of gene therapy products using adeno-associated virus (AAV) vectors is progressing, and the gene therapy market is rapidly expanding. AAV shows no pathogenicity in the human body, has extremely low cytotoxicity and, unlike lentiviral and retroviral vectors, rarely integrates into chromosomes. Consequently, risk associated with AAV was thought to be low. In recent years, however, adverse events such as hepatotoxicity have become apparent as cases accumulate among laboratory animals and in clinical trials. In this paper, we present an overview of the integration of AAV vectors into the genome of infected cells, which is thought to be the cause of adverse events.