Polycation liposome-mediated gene transfer in vivo

Abstract

The polycation liposome (PCL), a recently developed gene transfer system, is simply prepared by a modification of liposomes with cetylated polyethylenimine (PEI), and shows remarkable transgene efficiency with low cytotoxicity. In the present study, we investigated the applicability of PCLs for in vivo gene transfer, since the PCL-mediated transgene efficiency was found to be maintained in the presence of serum. PCLs composed of dioleoylphosphatidylethanolamine (DOPE) with 5 mol% cetyl PEI (PEI average mr. wt. 1800), were superior for transfection to those of dipalmitoylphosphatidylcholine (DPPC) and cholesterol (2:1 as molar ratio) with 5 mol% cetyl PEI in vitro, although the latter PCLs were more efficient for gene transfer in vivo. PCL-DNA complexes were injected into mice via a tail or the portal vein, with the DNA being a plasmid encoding green fluorescent protein (GFP) or luciferase; and the expression was monitored qualitatively or quantitatively, respectively. Tail vein injection resulted in high expression of both GFP and luciferase genes in lung, and portal vein injection resulted in high expression of both genes in the liver. Concerning the gene delivery efficiency, the PCL was found to be superior to PEI or cetyl PEI alone. The optimal conditions for in vivo transfection with PCLs were also examined.

Polyamine – Lipid Conjugates as Effective Gene Carriers: Chemical Structure, Morphology, and Gene Transfer Activity

“…The efficiency of these compounds was not influenced by the presence of 20% FBS, retaining 80-100 % of the activity (except compound DCP-PEI at 3/1 (w/w)). Such serum-resistant activity was also observed for the PCL gene transfection system previously reported (Matsuura et al, 2003). It is well known that serum often inhibits transfection; such inhibition is due to binding of negatively charged serum proteins to the cationic transfection reagents resulting in forming aggregates ineffective to the transfection.…”

“…In addition to investigation of intracellular trafficking of polycation-DNA complexes (polyplexes and lipoplexes), observation of morphology and metamorphosis of the complexes is very important to shed light on the mechanism of gene transfer and provide information for development of novel synthetic carriers (Koynova, Wang & MacDonald, 2006;Wan et al, 2008;Tarahovsky, Koynova & MacDonald, 2004). We have reported that polycationic liposomes (PCL) containing cetylated polyethylenimine (cetyl-PEI) possess high gene transfer activity (Yamazaki et al, 2000;Oku et al, 2001;Matsuura et al, 2003). The cetyl-PEI molecule is anchored by the hydrophobic cetyl portion and is distributed over the liposomal surface.…”

Suppression of tumor metastasis by NK4 plasmid DNA released from cationized gelatin

“…29 However, there are several drawbacks with each nonviral vector, including a low efficiency of gene transfection compared with viral vectors and a transient gene expression. In this study, we introduce a system of prolonged gene expression based on the sustained release of plasmid DNA from cationized gelatin microspheres.…”

“…27 In spite of the high transfection efficiency, the trials are limited by the adverse effects of the virus itself, such as immunogenicity and toxicity or the possible mutagenesis of the cells transfected. Many types of cationized polymers 28 and cationized liposomes 29 have been explored and complexed with the plasmid DNA or antisense oligonucleotide for gene expression. This approach is to enable the plasmid DNA to neutralize the anionic charge as well as to reduce the molecular size for enhanced efficiency of plasmid DNA transfection, which causes an increase in the gene expression.…”

Nanoparticle delivery of anti-metastatic NM23-H1 gene improves chemotherapy in a mouse tumor model

“…2,3 In spite of their high transduction efficiency, viral vectors are associated with immunogenicity, toxicity and possible mutagenesis of the target cells. 4 Non-viral vectors have become an attractive alternative, [5][6][7] but the low efficiency of transfection results in less efficient targeting of genes to the tissue of interest. The lack of an effective and safe gene targeting vector has become the major barrier to the wide application of gene therapy.…”