| 초록 |
Gene therapy presents a promising approach for the treatment of human disease. The aim of the gene therapy is to introduce a gene into cells either indirectly or directly for treatment of human diseases. Recently, there has been much interest in developing new formulations and materials for delivering foreign DNAs. Viral delivery systems have been used in many applications and clinical trials. In fact, around 75% of recent clinical protocols involving gene therapy use recombinant virus-based vectors for gene delivery; however, no definitive evidence has been presented for the clinical effectiveness of any gene therapy protocol. Although viral systems are potentially very efficient, the weakness of current methodology is attributable to the limitations of viral-mediated delivery, including toxicity, restricted targeting of specific cell types, limited DNA carrying capacity, production and packaging problems, recombination, and high cost. Lipid-based systems represent a promising class of gene carriers; however, their toxicity on repeated dosing and poor in vivo performance are major drawbacks in advancing them to the clinic. Therefore, there has been considerable interest in developing polymeric material as gene delivery vehicles. Polypropyleneimine dendrimer(PPD) as the novel highly branched molecule, has various molecular weights and a large number of controllable peripheral functionalities. Compared with another linear and branched polymers, the controllable surface functionality makes the dendrimers interesting class of gene delivery vehicles. A recent report showed that the PPD containing terminal amino groups has high transfection efficiency. In spite of many advantages of PDD, the PDD has cell cytotoxicity as similar to polyethyleneimine(PEI). High cell cytotoxicity in PDD is significant problem as a novel gene carrier. PDD can't practically use for the treatment of human disease due to it's cell cytotoxicity. G-PDD wil be expected to reduce cell cytotoxicity. Moreover, glucose have no harm in body or cells because it is a kind of sugar and one of the most common nutrient. All mammalian cell membranes contain proteins involved in the glucose transport and metabolize glucose through this transporter. In this study, we prepared G-PPD as a novel gene carrier. The G-PDD/DNA complex formation was confirmed by electrophoresis on agarose gel. Particle sizes and zeta potential were measured using dynamic light scattering. Cytotoxicity test was checked by cell proliferation assay kit with 293T cell line. The in vitro transfection into 293T cell was checked by luciferase assay. From MTT assay, the G-PDD remarkably increased cell viability with an increase of N/P ratio in vitro. |
