Advances in vaccine delivery systems against viral infectious diseases

Abstract

Although vaccines are available for many infectious diseases, there are still unresolved infectious diseases that threaten global public health. In particular, the rapid spread of unpredictable, highly contagious viruses has recorded numerous infection cases and deaths, and has changed our lives socially or economically through social distancing and wearing masks. The pandemics of unpredictable, highly contagious viruses increase the ever-high social need for rapid vaccine development. Nanotechnologies may hold promise and expedite the development of vaccines against newly emerging infectious viruses. As potential nanoplatforms for delivering antigens to immune cells, delivery systems based on lipids, polymers, proteins, and inorganic nanomaterials have been studied. These nanoplatforms have been tested as a means to deliver vaccines not as a whole, but in the form of protein subunits or as DNA or mRNA sequences encoding the antigen proteins of viruses. This review covers the current status of nanomaterial-based delivery systems for viral antigens, with highlights on nanovaccines against recently emerging infectious viruses, such as severe acute respiratory syndrome coronavirus-2, Middle East respiratory syndrome coronavirus, and Zika virus.

Keywords: Nanotechnology; Severe acute respiratory syndrome coronavirus-2; Vaccine delivery systems; Viral infectious diseases.

Fig. 1

Delivery systems of nucleic acids encoding viral antigens. a Mannosylated zwitterionic lipid-based cationic liposomes. Adapted from [15]. b PEI polymeric nanoparticle-coated microneedle. Adapted from [16]. c Peptide nanofiber-based hydrogel. Adapted from [18]. d Fullerenol nanoparticles. Adapted from [19]. e Cationic polymer-modified gold nanorods. Adapted from [17]. f Dendrimer-based nanomaterials for RNA vaccine delivery. Adapted from [27]. g saRNA polyplexes with high molar mass pABOLs. Adapted from [28]. h PLA-based cationic peptides/mRNA nanocomplex. Adapted from [31]. i Co-polymer based cationic nanomicelles. Adapted from [30]

Fig. 2

Delivery systems of protein- and VLP-based vaccines against viral infectious diseases. a The 3M2e-rHF fusion protein and 3M2e-rHF fusion protein-based nanoparticle. Reprinted with permission from [38]. b Double-layered protein nanoparticles for protein antigen delivery. Reprinted with permission from [39]. c Schematic illustration of the expression and in vivo assembly of P22-SpyTag and preparation of P22-HA_head. Reprinted with permission from [45]. d Schematic illustration of preparation of an avian coronavirus VLP. Reprinted with permission from [50]

Fig. 3

Illustration of a nanovaccine against COVID-19. a Cationic squalene emulsion was composed of cationic lipid DOTAP, Span60, Tween 80, and squalene. To enhance the stability of the formulation, superparamagnetic iron oxide nanoparticles (SPIO) were loaded in oil phase. The formulation was complexed with saRNA (repRNA-CoV25) for intramuscular delivery. Adapted from [63]. b After endocytosis, SAS-CoV2-encoding saRNA was translated to the spike protein, and processed in antigen presenting cells. MHC I and MHC II antigen presentations induced SARS-CoV-2 specific cellular and humoral immune responses, respectively

Fig. 4

Ferritin-fused protein nanoparticles against MERS-CoV. Fusion proteins were composed of RNA binding domain (hRID), the receptor-binding domain (RBD) of MERS-CoV, and ferritin. Three fusion proteins were designed with different linker peptides between ferritin and RBD. Reprinted with permission from [68]

Fig. 5

Lipid nanoparticles for delivery of Ebola virus glycoprotein. Ebola virus glycoproteins were loaded to lipid nanoparticles via histidine and nickel interactions. Reprinted with permission from [82]. NTA nitrilotriacetic acid, ICMV interbilayer-crosslinked multilamellar vesicles, DTT dithiothreitol