Chapter 14 - Mechanisms of Cationic Liposome-Mediated Transfection of the Lung Endothelium

Abstract

Cationic liposomes have been successfully used to transfect lung endothelium by systemic administration. Cationic liposome technology has become well established for introducing DNA into cells and these liposomes have been considered to be among the most promising carriers for gene therapy. This chapter explores the mechanisms of cationic liposome. However, in spite of the effectiveness of cationic liposomes in transfecting cells in vitro, their transfection efficiency in vivo is still fairly low compared to that of viral vectors. The transfection efficiency of DNA/liposome complexes depends on various factors. These are the structure of the specific cationic lipid used, the ratio of cationic lipid to DNA, liposome composition, the particle diameter, and the injected dose. It is believed that these physicochemical parameters exert their effects on transfection efficiency by affecting the interactions between liposome/DNA complexes and the lung endothelium. This chapter explains how these physicochemical parameters affect the ultimate transfection activity of DNA/liposome complexes. The chapter focuses on transfection of the lung endothelium by systemically administered DNA and DNA/liposome complexes. Moreover, some thoughts are provided on means to further enhance the level of gene expression in lung endothelium through systemic gene delivery.