Cationic polysaccharides for gene delivery

DNA can be delivered into the cell nucleus using physical means or using specific carriers that carry the genes into the cells for gene expression. Of the various methods developed for delivering genes, gene carriers have been extensively investigated as transfecting agents for therapeutic genes in gene therapy. Gene carriers are divided into two main groups: viral carriers, where the DNA to be delivered is inserted into a virus; and cationic molecular carriers that form electrostatic interactions with DNA. Successful gene therapy depends on the efficient delivery of genetic materials into the cells nucleus and its effective expression within these cells.1 Although at present, the in vivo expression levels of synthetic molecular gene vectors are lower than for viral vectors and gene expression is transient; these vehicles are likely to present several advantages including safety, low immunogenicity, capacity to deliver large genes, and large-scale production at low cost. The two leading classes of synthetic gene delivery systems that have been mostly investigated involve the use of either cationic lipids or cationic polymers.