Gene therapy using an AAV vector. A new gene is inserted into a cell using the AAV protein shell. The new gene often integrates in a precise location and then makes functional protein to treat a disease.
The adeno-associated virus serotype 1 (AAV1) viral vector delivers an intact copy of the human lipoprotein lipase (LPL) gene. Data from the clinical trials indicates that fat concentrations in blood were reduced between 3 and 12 weeks after injection, in nearly all patients. The advantages of AAV include apparent lack of pathogenicity, delivery to non-dividing cells, and non-integrating in contrast to retroviruses, which show random insertion with accompanying risk of cancer. AAV also presents very low immunogenicity, mainly restricted to generating neutralizing antibodies, and little well defined cytotoxic response. The cloning capacity of the vector is limited to replacement of the virus's 4.8 kilobase genome.
^Chirmule N, Propert K, Magosin S, Qian Y, Qian R, Wilson J (September 1999). "Immune responses to adenovirus and adeno-associated virus in humans". Gene Therapy6 (9): 1574–83. doi:10.1038/sj.gt.3300994. PMID10490767.
^Ponnazhagan S, Mukherjee P, Yoder MC, et al. (April 1997). "Adeno-associated virus 2-mediated gene transfer in vivo: organ-tropism and expression of transduced sequences in mice". Gene190 (1): 203–10. doi:10.1016/S0378-1119(96)00576-8. PMID9185868.