Cationic liposome

Cationic liposomes are structures that are made of positively charged lipids and are increasingly being researched for use in gene therapy due to their favorable interactions with negatively charged DNA and cell membranes. In 1987, Philip Felgner published the first approach to using cationic lipids to transfect DNA into cells, based on his research into cationic lipids at Syntex from 1982 to 1988. Upon interacting with negatively charged DNA, cationic liposomes form clusters of aggregated vesicles. At a critical density the DNA is condensed and becomes encapsulated within a lipid bilayer, although it is possible that the liposomes bind along the surface of the DNA, retaining its shape. They are also able to interact with negatively charged cell membranes more readily than classical liposomes. Fusion between cationic vesicles and cell surfaces can deliver the DNA directly across the plasma membrane. This process bypasses the endosomal-lysosomal route which leads to degradation of anionic liposome formulations.