Liposomes; from synthesis to targeting macrophages

Abstract

Liposomes are a proposed tool to use for cell and tissue specific drug targeting. Because of their phospholipid membranes and carrying capacity within their spheres, liposomes are of particular interest for clinical applications. Stealth liposomes are especially important for these clinical applications because they are able to avoid the body’s immune system. When it comes to synthesizing these liposomes, there are two major categories of synthesis techniques including active and passive loading. This paper focuses on passive loading techniques which involve mechanical dispersion methods, solvent dispersion methods, and detergent removal. Each of these categories of passive loading techniques has several methods for preparation, all of which aim at producing a homogeneous solution of liposomes with a high loading efficiency. Beyond preparation techniques, this paper also explores the use of liposomes in targeting macrophages to reduce inflammation in various diseases. From this, it has been found that liposomes are able to effectively target macrophages as well as deliver drugs to macrophages that cause the cells to reverse from a pro-inflammatory response to an anti-inflammatory response. These findings are critical as they may lead to further targeting of liposomes to specific cell types to treat other diseases in humans.