Abstract
Adenoviral gene transfer is a valuable tool in molecular biology
research. In order to be an efficient and safe vector, adenovirus
structure and infection mechanism as well as molecular biology of the
used transgene need to be well studied. The aim of this study was to
evaluate the role of adenovirus as a gene transfer vector from several
perspectives. Adenovirus uses receptor-mediated endocytosis in order to
enter the target cell. The effect of Rab5 GTPase on adenovirus entry and
gene transfer efficiency was examined first. Next, adenovirus was used
as an investigatory tool in the cardiovascular research, focused on
clarifying the role of adrenomedullin (AM) in heart and vascular
remodeling. Finally, a model of adenoviral gene transfer into skin
fibroblasts was used.
The role of Rab5 GTPase in the adenovirus endocytosis was examined
in HeLa cells using Cy3-labeled adenovirus, and gene transfer efficiency
using β-galactosidase encoding adenovirus. Rab5 increased both
adenovirus uptake and gene transfer, whereas dominant negative Rab5S34N
decreased both endocytosis and gene transfer. The data indicate that
Rab5 is needed in mediating the adenovirus uptake into the target
cell.
In the rat heart, adenovirus-mediated AM gene transfer transiently
improved systolic function both in vivo and
in vitro. AM caused activation of translocation of
protein kinases C ε and δ, whereas phosphorylation of p38
mitogen activated protein kinase was decreased in the left ventricle. AM
significantly attenuated the development of angiotensin II-induced
cardiac hypertrophy. In rats with myocardial infarction, AM enhanced
dilatation of left ventricle and thinning of anterior wall. The role of
AM in neointima formation was evaluated in rat artery after endothelial
injury. Intravascular AM gene transfer decreased neointimal growth and
increased neointimal myofibroblasts apoptosis. These results show that
AM regulates left ventricular systolic function and remodeling in the
heart, and plays a role in pathological vascular remodeling.
Adenovirus-mediated lysyl hydroxylase (LH) gene transfer into skin
fibroblasts of type VI Ehlers-Danlos syndrome patient and rat skin
increased functional LH production, elevated LH activity, and human LH
mRNA production both in vitro and in
vivo. LH gene replacement therapy may thus lead to
possibilities to improve skin wound healing in Ehlers-Danlos syndrome
patients