In vivo transgene expression from an adenoviral vector is altered following a 6-OHDA lesion of the dopamine system

Abstract

We have investigated the in vivo dynamics of an adenovirus-based, LacZ expressing vector, RAd36, at different doses, when injected unilaterally into the corpus striatum of normal rats. We have further investigated the characteristics of this vector in the presence of a 6-OHDA lesion of the nigrostriatal pathway. The dopamine-depleting lesion had an effect on both the number and the distribution of cells transduced by the adenoviral vector. The lesioned side of the brain contained significantly greater numbers of β-galactosidase positive cells than the unlesioned side at 3 days, 1 week and 4 weeks post-injection and the distribution of transduced cells was altered by the presence of a dopamine lesion. We conclude that the increased levels of transgene expression seen in the lesioned hemisphere are due to a change in the diffusion characteristics of the injected vector in the lesioned hemisphere. These results indicate that, when investigating the use of virus-based vectors, ultimately for use in gene therapies in the CNS, the in vivo dynamics of the vector need to be assessed not only in the normal brain, but also in the pathological brain state such as animal models of target diseases.

Comparison of incremental and accelerating protocols of the rotarod test for the assessment of motor deficits in the 6-OHDA model

“…Immunohistochemistry was carried out using the streptavidin biotin method (StreptABC/HRP kit, DAKO). The horseradish peroxidase label was visualised with 3,3 -diaminobenzidine (Torres et al, 2005).…”

Mitochondrial imaging in dorsal root ganglion neurons following the application of inducible adenoviral vector expressing two fluorescent proteins

“…In particular, they can accept relatively large insertions of foreign DNA and allow the infection of a broad range of post-mitotic cells with high efficiency. Previous reports have successfully demonstrated the application of adenoviral vectors in cellular trafficking (Dinh et al, 2005), targeting expression of neurotrophic factors (Torres et al, 2005), as a marker to examine genetically altered neurons (Smith et al, 1997) and to analyze the functional genes in vivo (Romero and Smith, 1998;Wang et al, 2006). In addition, recombinant adenoviral vectors remain epichromosomal, which reduce the possibility of irreversible chromosomal alteration (Mitani and Kubo, 2002;Sato et al, 2002;Amalfitano and Parks, 2002).…”