Recent Advances in Liposome-Based Nanoparticles for Antigen Delivery

Over the last several years, new generation vaccine systems that are based on proteins, peptides, or DNA have shown great promise compared to the traditional vaccines based on inactivated or attenuated whole organisms. However, due to the lower efficiencies and higher cost of these new generation vaccines, they are seldom used alone. Rather, their formulations often contain adjuvants, either to enhance the immune responses or to reduce the effective dose. The present article will provide a brief overview of recent advances in peptide‐ or protein-based cancer vaccine adjuvants, focusing mainly on Liposome‐Protamine‐DNA (LPD) nanoparticle‐mediated antigen delivery. The molecular basis and signaling pathways leading to the activation and maturation of antigen presenting cells (APC) by adjuvants are discussed. Another consideration of the liposome‐based vaccine delivery system is the antigen targeting. Therefore, the second part of this review will discuss the strategies used for targeted delivery of antigen, from the organ level to the cellular, the sub‐cellular, and the molecular level.