Emerging lipids-based adjuvant delivery technologies for vaccines

Historically infectious disease pandemics have caused health emergencies for humans as well as livestock on numerous occasions. In such situations and on a routine basis vaccination has emerged as an effective intervention for prevention and eradication of pathogenic infections. As the field of vaccine research has progressed, next generation vaccine platforms including protein subunits, recombinant proteins, nucleic acids (DNA, mRNA) and more have been discovered which rely on more complex adjuvants with capability to function as delivery carriers for the vaccine modalities helping achieve effective immune response, stability and safety. Lipids-based particulate systems are emerging, promising and flexible choices as adjuvant delivery systems because their makeup can be adjusted to suit the vaccine modality and the delivery needs. In this review open-source literature on development and evaluation of lipids-based delivery platforms which can also serve as vaccine adjuvants is studied. The survey reveals that the most lipids-based vaccine adjuvant delivery systems are particulate, such as emulsions, micro/nanoparticles, and liposomes facilitating the delivery of vaccine modalities to antigen-presenting cells (APCs) or other target cells enabling the nucleic acid translation and protein synthesis. This article is aimed at providing an overview of the lipids-based adjuvant delivery platforms with respect to the literature reports enlightening their applications in the field of vaccines which would serve as a reference for scientists undertaking vaccine product development.