Abstract
At present, vectors widely used for gene transduction are retroviruses and adenoviruses. However, the transduction using these vectors are primarily conducted ex vivo. The direct in vivo gene delivery method to target tumor cells are required. Trials to augment specificity of gene targeting to tumor cells have been in progress including approaches to use modified virus particles by gene technology instead of wild type particles or to take advantage of ligand-receptor or antibody-antigen systems by allowing vector DNAs to bind these ligand and antibodies. Transferrin receptor(TfR) is widely distributed on actively proliferating cells and is therefore an appropriate target for in vivo gene delivery into those cells. We developed a simple method to conjugate double-stranded DNA(biotinylated β-galactosidase DNA after transamination) to biotinylated Tf via streptavidin and demonstrated successful transduction of the conjugate into TfR-positive human leukemia(K562) and human colon cancer(M7609) cells. We achieved a better transduction rate than the presently available results of Tf-polylysine-DNA complex. The present method may provide a novel technique for gene transduction, which may be used especially to transfer various DNA vectors into cells specifically expressing TfR, in vivo as well as in vitro.
