Virus adéno-associé

Adeno-associated viruses (AAV) are small viruses that infect humans and some other primate species. They belong to the genus Dependoparvovirus, which in turn belongs to the family Parvoviridae. They are small (approximately 26 nm in diameter) replication-defective, nonenveloped viruses and have linear single-stranded DNA (ssDNA) genome of approximately 4.8 kilobases (kb). Several features make AAV an attractive candidate for creating viral vectors for gene therapy, and for the creation of isogenic human disease models. Gene therapy vectors using AAV can infect both dividing and quiescent cells and persist in an extrachromosomal state without integrating into the genome of the host cell. In the native virus, however, integration of virally carried genes into the host genome does occur. Integration can be important for certain applications, but can also have unwanted consequences. Recent human clinical trials using AAV for gene therapy in the retina have shown promise. In March 2023, a series of Nature papers linked infection of adeno-associated virus 2 (AAV2) to a wave of childhood hepatitis. The adeno-associated virus (AAV), previously thought to be a contaminant in adenovirus preparations, was first identified as a dependoparvovirus in the 1960s in the laboratories of Bob Atchison at Pittsburgh and Wallace Rowe at NIH. Serological studies in humans subsequently indicated that, despite being present in people infected by helper viruses such as adenovirus or herpes virus, AAV itself did not cause any disease. Wild-type AAV has attracted considerable interest from gene therapy researchers due to a number of features. Chief amongst these was the virus's apparent lack of pathogenicity. It can also infect non-dividing cells and has the ability to stably integrate into the host cell genome at a specific site (designated AAVS1) in the human chromosome 19. This feature makes it somewhat more predictable than retroviruses, which present the threat of a random insertion and of mutagenesis, which is sometimes followed by development of a cancer.