%0 Journal Article
%T Efficient Nonviral Gene Therapy Using Folate-Targeted Chitosan-DNA Nanoparticles In Vitro
%A Christian Jreyssaty
%A Qin Shi
%A Huijie Wang
%A Xingping Qiu
%A Fran£żoise M. Winnik
%A Xiaoling Zhang
%A Kerong Dai
%A Mohamed Benderdour
%A Julio C. Fernandes
%J ISRN Pharmaceutics
%D 2012
%R 10.5402/2012/369270
%X Nonviral cationic polymers like chitosan can be combined with DNA to protect it from degradation. The chitosan is a biocompatible, biodegradable, nontoxic, and cheap polycationic polymer with low immunogenicity. The objective of this study was to synthesize and then assess different chitosan-DNA nanoparticles and to select the best ones for selective in vitro transfection in human epidermoid carcinoma (KB) cell lines. It revealed that different combinations of molecular weight, the presence or absence of folic acid ligand, and different plasmid DNA sizes can lead to nanoparticles with various diameters and diverse transfection efficiencies. The intracellular trafficking, nuclear uptake, and localization are also studied by confocal microscopy, which confirmed that DNA was delivered to cell nuclei to be expressed. 1. Introduction Gene therapy is being applied to various health problems, such as cancer, acquired immunodeficiency syndrome, and cardiovascular diseases. The main challenge is to develop a method that delivers the transgene to selected cells, where a proper gene expression can be achieved. Several trials have aimed at introducing genes straight into human cells, focusing on diseases caused by single-gene defects, such as cystic fibrosis [1], hemophilia [2], adenosine deaminase deficiency [3], muscular dystrophy [4], and sickle cell anemia [5]. Ideally, gene therapy must protect DNA against degradation by nucleases in intercellular matrices so that the disposition of macromolecules is not affected. Transgenes should be brought across the plasma membrane and into the nucleus of targeted cells but should have no detrimental effects. Hence, interaction with blood components, vascular endothelial cells, and uptake by the reticuloendothelial system must be avoided [6]. For gene therapy to succeed, small-sized systems must internalize into cells and pass to the nucleus. Also, flexible tropisms allow applicability to a range of disease targets. Last but not least, such systems should be able to escape endosome-lysosome processing for endocytosis [7]. Viral gene therapy consists of using viral vectors which, given their structure and mechanisms of action, are good candidates or models to carry therapeutic genes efficiently, leading to long-term expression [8, 9]. They have the natural ability to enter cells and express their own proteins. Nowadays, most viral vectors used are retroviruses, herpes virus, adenoviruses, and lentiviruses [10]. However, viral vectors can cause several problems to patients, namely, toxicity, oncogenic effects, and immune and
%U http://www.hindawi.com/journals/isrn.pharmaceutics/2012/369270/