Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2012 Jun;19(6):649-58.
doi: 10.1038/gt.2012.6. Epub 2012 Feb 23.

Intracellular transport of recombinant adeno-associated virus vectors

Affiliations
Review

Intracellular transport of recombinant adeno-associated virus vectors

M Nonnenmacher et al. Gene Ther. 2012 Jun.

Abstract

Recombinant adeno-associated viral vectors (rAAVs) have been widely used for gene delivery in animal models, and are currently evaluated for human gene therapy after successful clinical trials in the treatment of inherited, degenerative or acquired diseases, such as Leber congenital amaurosis, Parkinson disease or heart failure. However, limitations in vector tropism, such as limited tissue specificity and insufficient transduction efficiencies of particular tissues and cell types, still preclude therapeutic applications in certain tissues. Wild-type adeno-associated viruses (AAVs) are defective viruses that require the presence of a helper virus to complete their life cycle. On the one hand, this unique property makes AAV vectors one of the safest available viral vectors for gene delivery. On the other, it also represents a potential obstacle because rAAV vectors have to overcome several biological barriers in the absence of a helper virus to transduce successfully a cell. Consequently, a better understanding of the cellular roadblocks that limit rAAV gene delivery is crucial and, during the last 15 years, numerous studies resulted in an expanding body of knowledge of the intracellular trafficking pathways of rAAV vectors. This review describes our current understanding of the mechanisms involved in rAAV attachment to target cells, endocytosis, intracellular trafficking, capsid processing, nuclear import and genome release with an emphasis on the most recent discoveries in the field and the emerging strategies used to improve the efficiency of AAV-derived vectors.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Model of Entry and Intracellular Trafficking of AAV Vectors. Following binding to a receptor/co-receptor complex, rAAV enters target cell through endocytosis via one or more of the following pathways: CLIC/GEEC endocytosis, clathrin-mediated endocytosis (CCP) or caveolar endocytosis (CAV). Virions are sorted towards the trans-Golgi network (TGN) along a retrograde transport pathway presumably involving trafficking via early endosomes (EE), followed by late endosomes (LE), perinuclear recycling endosomes (PNRE) or both. Capsid conformation changes and exposure of the PLA2 domain (spikes) allows cytoplasmic release from the Golgi apparatus or the Endoplasmic Reticulum (ER), and nuclear import via the nuclear pore complex (NPC). After nuclear import, intact capsids accumulate in the nucleolus (No) before mobilization into the nucleoplasm (NP) and genome release by partial uncoating. Some of the steps indicated are hypothetical and have not been conclusively proven yet.

Similar articles

Cited by

References

    1. Kaneda Y. Update on non-viral delivery methods for cancer therapy: possibilities of a drug delivery system with anticancer activities beyond delivery as a new therapeutic tool. Expert Opin Drug Deliv. 2010;7(9):1079–93. - PubMed
    1. Cavazzana-Calvo M, Hacein-Bey S, de Saint Basile G, Gross F, Yvon E, Nusbaum P, et al. Gene therapy of human severe combined immunodeficiency (SCID)-X1 disease. Science. 2000;288(5466):669–72. - PubMed
    1. Gaspar HB, Parsley KL, Howe S, King D, Gilmour KC, Sinclair J, et al. Gene therapy of X-linked severe combined immunodeficiency by use of a pseudotyped gammaretroviral vector. Lancet. 2004;364(9452):2181–7. - PubMed
    1. Kohn DB, Candotti F. Gene therapy fulfilling its promise. N Engl J Med. 2009;360(5):518–21. - PubMed
    1. Simonelli F, Maguire AM, Testa F, Pierce EA, Mingozzi F, Bennicelli JL, et al. Gene therapy for Leber's congenital amaurosis is safe and effective through 1.5 years after vector administration. Mol Ther. 2010;18(3):643–50. - PMC - PubMed

Publication types