Mechanisms for Cationic Lipids in Gene Transfer

For over a decade, cationic lipids have been used for gene transfer both in cell culture and in animals [1,2]. A cationic lipid is a positively charged amphiphile with a hydrophilic head and a hydrophobic tail that self-associates in aqueous solution to form either micelles or bilayer liposomes (Table 1). This results in a multivalent particle which can then interact with the negative charges on a polynucleotide, such as DNA. This complex of cationic lipid and DNA has been given the term lipoplex [3].