Cationic liposornes as vaccine adjuvants

Cationic liposomes are lipid-bilayer vesicles with a positive surface charge that have re-emerged as a promising new adjuvant technology. Although there is some evidence that cationic liposomes; themselves can improve the immune response against coadministered vaccine antigens, their main functions are to protect the antigens from clearance in the body and deliver the antigens to professional antigen-presenting cells. In addition, cationic liposomes can be used to introduce immunomodulators to enhance and modulate the immune response in a desirable direction and, thereby, represent an efficient tool when designing tailor-made adjuvants for specific disease targets. In this article we review the recent progress on cationic liposomes as vehicles, enhancing the effect of immunomodulators and the presentation of vaccine antigens.