Chitosan conjugated DNA nanoparticles in gene therapy

Conventional gene delivery with viral or lipid carriers-are plagued by disadvantages such as low transfection efficiency, cytotoxicity and immunogenicity. Numerous techniques are being probed to help improve efficiency, including the development of biodegradable polymers with reduced toxicity, incorporation of cell targeting moieties, improved chemistry for syntheses of polymers with uniform size and topology etc. Chitosan, a naturally occurring cationic polysaccharide, is emerging as a potential candidate for gene delivery applications with its reasonable transfection efficiency combined with a minimal level of cytotoxicity. The chitosan and their nanoparticles have potential to form polyelectrolyte complex with DNA and it is useful for non-viral vectors for gene therapy applications. Hence, the objective of this review is to summarize the recent advances in gene therapy giving emphasis to the applications of chitosan nanoparticles as gene carriers in enhancing cellular uptake and transfection efficiency. (C) 2009 Elsevier Ltd. All rights reserved.