Abstract
Cationic liposomes have been considered as a potential non-viral vector for gene delivery, which possess a low immunogenicity unlike viral vectors. The gene transfer effcieney of cationic liposomes is lower than that of viral vectors but the advance of recent study revealed to enhance the gene expression levels of cationic liposomes. The most problem of cationic liposomes seem to be the lack of organ or cell selectivity because the lung shows highest gene expression organ after intravenous injection. Applying a cell-specific targeting technology to the liposomes would improve in vivo gene delivery and reduce unexpected side effects. Liver parencymal cells and liver non-parenchymal cells exclusively express large numbers of high affinity asialoglycoprotein and mannose receptors, respectively. Receptor-mediated gene delivery systems seems to introduce foreign DNA into specific cell types in vivo. However, we have confirmed that not only the nature of the ligands grafted to carriers but also the overall physicochemical properties of the complexes need to be optimized for the cell-selective targeting of plasmid DNA. In this article, we attempt to evaluate the the gene delivery system based on the physicochemical properties of plasmid DNA and plasmid DNA/cationic liposomes or glycosylated cationic liposomes.
