DNA complexes with reducible cationic lipid for gene transfer

Adenovirus in a synthetic membrane wrapper: an example of hybrid vigor?

Nucleic acid delivery applications require the development of carrier systems that are effective, selective, and non-toxic. Many different viral and non-viral approaches, including the use of retroviruses, adenoviruses, liposomes, and dendrimers, have been investigated. Unfortunately, issues still remain with regard to the safety and efficiency of these delivery vehicles. In this Perspective, the challenges of designing a stable vector that is capable of effective gene therapy are highlighted. Progress in the area is also presented, including the work of Kostarelos and co-workers appearing in this issue of ACS Nano, in which they describe a novel delivery vehicle that consists of lipid envelopes encasing viral nanoparticles.

Soluble sustained release gene delivery system

Delivery of genetic substance to target cells remains an obstacle for efficient utilization of gene therapy approaches. In this study, we describe a formulation of methacrylate acid copolymer carrier of DNA, in which the release rate of the gene can be controlled by pH. Plasmid release was coupled with the polymer's dissolution, which was accelerated in alkali conditions. The released plasmid was intact and bioactive, although alteration from closed circular supercoil to relaxed conformation was observed. Confocal laser scanning microscopy detected the plasmid DNA along the central layers of the polymeric film. Gene delivery systems controlled by the dissolution of the polymeric films offer flexibility in quantity and size of the incorporated DNA, and therefore could have a potential for in vivo use.