MRNA-lipid Nanoparticle Vaccines: Structure and Delivery

Abstract

As the latest generation of vaccine production technology, mRNA vaccine has achieved vaccine production and clinical application, such as COVID-19 mRNA vaccine. However, a substantial inherent limitation in the development of mRNA vaccines is that mRNA is chemically unstable and susceptible to lysed by lysosome. Therefore, it is necessary to develop suitable vectors for mRNA. Today, the mainly COVID-19 vaccines include mRNA produced by Modera was approved by the FDA in the world. mRNA-1273 is a nucleic acid vaccine delivered by a lipid nanoparticle (LNP). As mRNA vaccines become widely available for mass vaccination, LNP have emerged as a popular delivery system. In this review, we introduce the history of MRNA after starting from mRNA vaccines, discusses the structure of LNP including ionizable cationic lipids, cholesterol, neutral lipids, PEG-lipids, and the role of each component. It also explains the mechanism of LNP delivery in mRNA vaccine and introduces different types of LNP, and describes several factors affecting particle delivery. It has been shown that the delivery of LNP is affected by particle size, particle surface charge, surface polyethylene glocalization and specific targeting modification. This review serves as a useful provides for insights into the delivery of LNP and the design of new therapeutic vaccines.