New Vector Carries Big Genes

Newly developed vector derived from AAV has been used to successfully carry large genes into cells and improve eye function in a mouse model of an inherited disease causing progressive loss of sight.

In gene therapy, the curative gene is packages in an agent known as vector, which carries the gene into cells where it is required. The most common vector is derived from adeno-associated virus (AAV) has linear single-stranded DNA genome of approximately 4.7-kilobases. From the data generated by Alberto Auricchio and colleagues reveals that the new vectors derived from AAV known as AAV5 can now accommodate large gene, and AAV5 could be used to induce cells to successfully convert the information in the large genes into protein properly. AVV5 has a linear single stranded DNA genome of 5kb and the new AAV5 opens possibility of developing better gene delivery vehicles, in the case of most gene therapy targets on retinal cells can be transfected by AAV5 as well it is the most divergent of the group of primate AAV.
In the study on mouse, When AAV5 containing the mouse gene Abca4, which is the mouse correlate of the gene mutated in individuals with recessive Stargardt disease (an autosomal recessive genetic form of juvenile macular degeneration that causes progressive vision loss), was injected into the eye of mice lacking Abca4, improvement in the function of the eye was observed. Therefore the vectors of AAV5 concluded could be useful for treating individuals with recessive Stargardt disease. Based on many studies of the behavior of AAV vector serotypes in the retina, including cell specificity, efficiency, stability and immunogenicity (Auricchio, 2003), AAV vectors are clearly a promising tool for retinal gene delivery in a wide variety of disease contexts and have been used to deliver therapeutic genes to correct disorders in animal models of various human retinal diseases

Further information:
1. Journal reference: Serotype-dependent packaging of large genes in adeno-associated viral vectors results in effective gene delivery in mice.
http://www.sciencedaily.com/releases/2008/04/080415185025.htm
2. Auricchio, 2003 A. Auricchio, Pseudotyped AAV vectors for constitutive and regulated gene expression in the eye, Vision Research 43 (2003), pp. 913–918. Article PDF (205 K) View Record in Scopus Cited By in Scopus (13)

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