Small Wonders-The Use of Nanoparticles for Delivering Antigen

Immunostimulatory chimeric protein encapsulated in gelatin nanoparticles elicits protective immunity against Pseudomonas aeruginosa respiratory tract infection

This study presents the design and fabrication of an innovative vaccine candidate targeting Pseudomonas aeruginosa (P. aeruginosa). The vaccine consists of gelatin nanoparticles (GNPs) encapsulating a chimeric protein (CP) derived from the ExoS and OprI proteins from P. aeruginosa. The physicochemical properties of the GNPs were assessed using dynamic light scattering (DLS) and electron microscopy. The toxicity, encapsulation efficacy, release profile, and effectiveness of CP-encapsulated GNPs (CP-GNPs) in an animal model were investigated. The resulting nanovaccine demonstrated uniform spherical particles with an average size of 135 nm and an encapsulation efficiency of 85 %. The release assay revealed that 23 % of the antigen was released from the CP-GNPs after 20 days. The GNPs did not exhibit any toxic effects on L929 cells in vitro. The formulation induced both systemic and mucosal antibody responses. Additionally, CP-GNPs stimulated cytokine responses, including IFN-γ, IL-4, and IL-17, indicating the induction of both humoral (Th2) and cellular (Th1) responses. The CP-encapsulated GNPs formulation effectively protected the mice lungs against experimental respiratory tract infection, reducing colony count and inflammation. These findings suggest that CP-GNPs hold promise as a potential strategy for preventing respiratory tract infections caused by P. aeruginosa. Further research is needed to explore its clinical application.

Nanocapsules Comprised of Purified Protein: Construction and Applications in Vaccine Research

Nanoparticles show great promise as a platform for developing vaccines for the prevention of infectious disease. We have been investigating a method whereby nanocapsules can be formulated from protein, such that the final capsules contain only the cross-linked protein itself. Such nanocapsules are made using a silica templating system and can be customised in terms of size and porosity. Here we compare the construction and characteristics of nanocapsules from four different proteins: one a model protein (ovalbumin) and three from infectious disease pathogens, namely the influenza virus, Helicobacter pylori and HIV. Two of the nanocapsules were assessed further. We confirm that nanocapsules constructed from the urease A subunit of H. pylori can reduce subsequent infection in a vaccinated mouse model. Further, we show that capsules constructed from the HIV gp120 protein can be taken up by dendritic cells in tissue culture and can be recognised by antibodies raised against the virus. These results point to the utility of this method in constructing protein-only nanocapsules from proteins of varying sizes and isoelectric points.

Design and fabrication of a vaccine candidate based on rOmpA from Klebsiella pneumoniae encapsulated in silk fibroin-sodium alginate nanoparticles against pneumonia infection

The present study describes the design and fabrication of a novel vaccine candidate based on the outer membrane protein A (rOmpA) from Klebsiella pneumoniae (K. pneumoniae) encapsulated in silk fibroin-sodium alginate nanoparticles (SF-SANPs) against K. pneumoniae-mediated pneumonia. The physicochemical properties, toxicity, release profile, and in vivo potency of SF-SANPs encapsulated with rOmpA were evaluated. The spherical nano vaccine was created with an average particle size of 160 nm and an encapsulation efficiency of 80 %. Antigen release from SF-SANPs was 40 % after 22 days release assay. The SF-SANPs showed a zeta potential of -24.8 mV and had no toxic effect on the L929 cells in vitro. It was found that SF-SANPs in the vaccine formulation promoted systemic and mucosal antibodies and also stimulated cytokine responses, inducing both humoral (Th2) and cellular (Th1) immune responses, with a Th1-polarized response. The vaccine candidate was effective in protecting the mice lung against experimental pneumonia and reducing inflammation. These findings suggest that the rOmpA-based vaccine encapsulated in SF-SANPs could be a promising strategy for preventing pneumonia caused by K. pneumoniae.

Dual-Antigen Subunit Vaccine Nanoparticles for Scrub Typhus

Orientia tsutsugamushi is the causative pathogen of scrub typhus, an acute febrile disease prevalent in the Asia-Pacific region that is spread to people through chigger bites. Despite the emerging threat, there is no currently available vaccine against O. tsutsugamushi. Here, we developed dual-antigen subunit vaccine nanoparticles using recombinant 47 kD and 56 kD proteins, which are immunogenic outer membrane antigens of O. tsutsugamushi. The biocompatible protein vaccine nanoparticles were formed via desolvation of r56 or r47E antigens with acetone, coating with an additional layer of the 56 kD protein, and stabilization with reducible homobifunctional DTSSP and heterobifunctional SDAD crosslinkers. The dual-antigen subunit vaccine nanoparticles significantly improved antigen-specific antibody responses in vaccinated mice. Most importantly, the dual-antigen nanoparticles coated with an additional layer of the 56 kD protein were markedly more immunogenic than soluble antigens or single-antigen nanoparticles in the context of cellular immune responses. Given the significance of cellular immune responses for protection against O. tsutsugamushi, these results demonstrate the potent immunogenicity of dual-layered antigen nanoparticles and their potential as a promising strategy for developing vaccines against scrub typhus.

An Evaluation of Urease A Subunit Nanocapsules as a Vaccine in a Mouse Model of Helicobacter pylori Infection

Using removable silica templates, protein nanocapsules comprising the A subunit of Helicobacter pylori urease (UreA) were synthesised. The templates were of two sizes, with solid core mesoporous shell (SC/MS) silica templates giving rise to nanocapsules of average diameter 510 nm and mesoporous (MS) silica templates giving rise to nanocapsules of average diameter 47 nm. Both were shown to be highly monodispersed and relatively homogenous in structure. Various combinations of the nanocapsules in formulation were assessed as vaccines in a mouse model of H. pylori infection. Immune responses were evaluated and protective efficacy assessed. It was demonstrated that vaccination of mice with the larger nanocapsules combined with an adjuvant was able to significantly reduce colonisation.

Macrophage Polarization Status Impacts Nanoceria Cellular Distribution but Not Its Biotransformation or Ferritin Effects

The innate immune system is the first line of defense against external threats through the initiation and regulation of inflammation. Macrophage differentiation into functional phenotypes influences the fate of nanomaterials taken up by these immune cells. High-resolution electron microscopy was used to investigate the uptake, distribution, and biotransformation of nanoceria in human and murine M1 and M2 macrophages in unprecedented detail. We found that M1 and M2 macrophages internalize nanoceria differently. M1-type macrophages predominantly sequester nanoceria near the plasma membrane, whereas nanoceria are more uniformly distributed throughout M2 macrophage cytoplasm. In contrast, both macrophage phenotypes show identical nanoceria biotransformation to cerium phosphate nanoneedles and simultaneous nanoceria with ferritin co-precipitation within the cells. Ferritin biomineralization is a direct response to nanoparticle uptake inside both macrophage phenotypes. We also found that the same ferritin biomineralization mechanism occurs after the uptake of Ce-ions into polarized macrophages and into unpolarized human monocytes and murine RAW 264.7 cells. These findings emphasize the need for evaluating ferritin biomineralization in studies that involve the internalization of nano objects, ranging from particles to viruses to biomolecules, to gain greater mechanistic insights into the overall immune responses to nano objects.

Quillaja brasiliensis nanoparticle adjuvant formulation improves the efficacy of an inactivated trivalent influenza vaccine in mice

The threat of viral influenza infections has sparked research efforts to develop vaccines that can induce broadly protective immunity with safe adjuvants that trigger robust immune responses. Here, we demonstrate that subcutaneous or intranasal delivery of a seasonal trivalent influenza vaccine (TIV) adjuvanted with the Quillaja brasiliensis saponin-based nanoparticle (IMXQB) increases the potency of TIV. The adjuvanted vaccine (TIV-IMXQB) elicited high levels of IgG2a and IgG1 antibodies with virus-neutralizing capacity and improved serum hemagglutination inhibition titers. The cellular immune response induced by TIV-IMXQB suggests the presence of a mixed Th1/Th2 cytokine profile, antibody-secreting cells (ASCs) skewed toward an IgG2a phenotype, a positive delayed-type hypersensitivity (DTH) response, and effector CD4⁺ and CD8⁺ T cells. After challenge, viral titers in the lungs were significantly lower in animals receiving TIV-IMXQB than in those inoculated with TIV alone. Most notably, mice vaccinated intranasally with TIV-IMXQB and challenged with a lethal dose of influenza virus were fully protected against weight loss and lung virus replication, with no mortality, whereas, among animals vaccinated with TIV alone, the mortality rate was 75%. These findings demonstrate that TIV-IMXQB improved the immune responses to TIV, and, unlike the commercial vaccine, conferred full protection against influenza challenge.

Self-assembled nanoparticles: A new platform for revolutionizing therapeutic cancer vaccines

Cancer vaccines have had some success in the past decade. Based on in-depth analysis of tumor antigen genomics, many therapeutic vaccines have already entered clinical trials for multiple cancers, including melanoma, lung cancer, and head and neck squamous cell carcinoma, which have demonstrated impressive tumor immunogenicity and antitumor activity. Recently, vaccines based on self-assembled nanoparticles are being actively developed as cancer treatment, and their feasibility has been confirmed in both mice and humans. In this review, we summarize recent therapeutic cancer vaccines based on self-assembled nanoparticles. We describe the basic ingredients for self-assembled nanoparticles, and how they enhance vaccine immunogenicity. We also discuss the novel design method for self-assembled nanoparticles that pose as a promising delivery platform for cancer vaccines, and the potential in combination with multiple therapeutic approaches.

Harnessing self-assembling peptide nanofibers toprime robust tumor-specific CD8 T cell responses in mice

Induction of tumor-specific CD8 + T cell responses is known as a major challenge for cancer vaccine development; here we presented a strategy to improve peptide nanofibers-mounted antitumor immune responses. To this end, peptide nanofibers bearing class I (Kb)-restricted epitope (Epi-Nano) were formulated with polyethylene imine backbone (Epi-Nano-PEI), and characterized using morphological and physicochemicalcharacterizationtechniques. Nanofibers were studied in terms of their uptake by antigen-presenting cells (APCs), antigen cross-presentation capacity, and cytotoxic activity. Furthermore, nanofibers were assessed by their potency to induce NLRP3 inflammasome-related cytokines and factors. Finally, the ability of nanofibers to induce tumor-specific CD8 T cells and tumor protection were investigated in tumor-bearing mice. The formulation of Epi-Nano with PEI led to the formation of short strand nanofibers with a positive surface charge, a low critical aggregation concentration (CAC), and an increased resistancetoproteolytic degradation. Epi-Nano-PEI was significantly taken up more efficiently by antigen-presenting cells (APCs), and was more potent in cross-presentation when compared to Epi-Nano. Moreover, Epi-Nano-PEI, in comparison to Epi-Nano, efficiently up-regulated the expression of NLRP3, caspase-1, IL-1b, IL18 and IL-6. Cell viability analysis showed that formulation of PEI with Epi-Nano not only abolished its cytotoxic activity, but surprisingly induced macrophage proliferation. Furthermore, it demonstrated that Epi-Nano-PEI triggered robust antigen-specific CD8+ T cell responses, and induced maximum antitumor response (tumor growth inhibition and prolonged survival) in tumor-bearing mice that were significantly higher compared to Epi-Nano. Taken together, the formulation of Epi-Nano with PEI is suggested as a promising strategy to improve nanofibers-mounted antitumor immune response.

Design and Preparation of Solid Lipid Nanoparticle (SLN)-Mediated DNA Vaccines

Increasing application of nucleic acid vaccines is driving demand for new delivery systems to improve stability and efficacy of DNA vaccines. Solid lipid nanoparticles (SLN) are a particulate carrier system composed of a solid lipid core and a cationic lipid surface suitable for binding negatively charged DNA. SLN delivery systems can be used to bind DNA resulting in an SLN/DNA complex (termed "lipoplex") which can be used as a potential vaccine.In this chapter, the methodologies associated with the use of SLNs as a DNA vaccine nanocarrier are discussed. First, requirements for an effective experimental lipoplex vaccine are discussed along with current and historical examples. Then, flowcharts for design and synthesis of lipoplex vaccines are outlined, followed by detailed materials and methods for synthesis and characterization of lipoplex vaccines.

In Vivo Sustained Release of Peptide Vaccine Mediated by Dendritic Mesoporous Silica Nanocarriers

Mesoporous silica nanoparticles have drawn increasing attention as promising candidates in vaccine delivery. Previous studies evaluating silica-based vaccine delivery systems concentrated largely on macromolecular antigens, such as inactivated whole viruses. In this study, we synthesized dendritic mesoporous silica nanoparticles (DMSNs), and we evaluated their effectiveness as delivery platforms for peptide-based subunit vaccines. We encapsulated and tested in vivo an earlier reported foot-and-mouth disease virus (FMDV) peptide vaccine (B₂T). The B₂T@DMSNs formulation contained the peptide vaccine and the DMSNs without further need of other compounds neither adjuvants nor emulsions. We measured in vitro a sustained release up to 930 h. B₂T@DMSNs-57 and B₂T@DMSNs-156 released 23.7% (135 µg) and 22.8% (132 µg) of the total B₂T. The formation of a corona of serum proteins around the DMSNs increased the B₂T release up to 61% (348 µg/mg) and 80% (464 µg/mg) for B₂T@DMSNs-57 and B₂T@DMSNs-156. In vitro results point out to a longer sustained release, assisted by the formation of a protein corona around DMSNs, compared to the reference formulation (i.e., B₂T emulsified in Montanide). We further confirmed in vivo immunogenicity of B₂T@DMSNs in a particle size-dependent manner. Since B₂T@DMSNs elicited specific immune responses in mice with high IgG production like the reference B₂T@Montanide™, self-adjuvant properties of the DMSNs could be ascribed. Our results display DMSNs as efficacious nanocarriers for peptide-based vaccine administration.

Gold Nanoparticles and Graphene Oxide Flakes Synergistic Partaking in Cytosolic Bactericidal Augmentation: Role of ROS and NOX2 Activity

Gold nanoparticles (GNPs) and graphene oxide flakes (GOFs) exerted significantly (p < 0.0001) supportive roles on the phagocytosis bioactivity of the immune cells of phagocytic nature against the Gram-positive and Gram-negative human pathogenic bacteria Staphylococcus aureus and Escherichia coli. Under experimental conditions, upon bacterial exposure, the combined GNPs and GOFs induced significant clearance of bacteria through phagosome maturation (p < 0.0001) from time-points of 6 to 30 min and production of reactive oxygen species (ROS, p < 0.0001) through the NADPH oxidase 2 (NOX2, p < 0.0001)-based feedback mechanism. The effects of the combined presence of GNPs and GOFs on phagocytosis (p < 0.0001) suggested a synergistic action underway, also achieved through elevated signal transduction activity in the bone-marrow-derived macrophages (BMDM, p < 0.0001). The current study demonstrated that GNPs’ and GOFs’ bactericidal assisting potentials could be considered an effective and alternative strategy for treating infections from both positive and negative bacterial strains.

Co-adsorption of synthetic Mincle agonists and antigen to silica nanoparticles for enhanced vaccine activity: A formulation approach to co-delivery

To date there is no clinically approved adjuvant to drive a protective T-helper cell 17 (Th17) immune response against Mycobacterium tuberculosis (Mtb). Trehalose Dimycolate (TDM) is a glycolipid molecule found in the cell wall of Mtb and similar species. Our team has discovered novel synthetic TDM derivatives that target Mincle receptors and when presented on the surface of amine functionalized silica nanoparticles (A-SNPs) adopt the requisite supramolecular structure for Mincle receptor agonism. Here we describe the preparation and characterization methods for these critical silica nanoparticles (SNPs) co-loaded with Mincle agonists (MAs) and a model antigen. In this work, A-SNPs with a particle diameter of 246 ± 11 nm were prepared and examined for co-adsorption of two synthetic MAs along with ovalbumin (OVA). Due to the insolubility of the studied MAs in aqueous environment, aggregation of the MAs made separation of the adjuvant-loaded A-SNPs from the free-form MAs via centrifugation very challenging. To facilitate separation, we synthesized modified SNPs with comparable amine surface functionalization to the original A-SNPs, but with a superparamagnetic iron oxide core (M-A-SNPs), to allow for magnetic separation. We also substituted Alexa Fluor 488-labeled ovalbumin (AF 488 OVA) for the un-tagged OVA to improve the sensitivity of our quantitation method. A RP-HPLC method was developed to simultaneously determine the amount of adsorption of both the Mincle adjuvant and the model antigen to the A-SNPs. AF488 OVA demonstrated higher than 90% adsorption, with or without the co-adsorption of MAs. Likewise, MAs exhibited higher than 80% adsorption in the presence or absence of antigen. The developed formulations were tested in vitro using murine RAW cells and human peripheral blood mononuclear cells, exhibiting good cytokine induction in both cell lines. Results from these studies indicate that A-SNPs could be used as a customizable presentation platform to co-deliver antigens along with different MAs of varying structural features and biophysical properties.

Protein-only nanocapsules induce cross-presentation in dendritic cells, demonstrating potential as an antigen delivery system

Templating has been demonstrated to be an efficient method of nanocapsule preparation. However, there have been no reports of using protein-only nanocapsules as an antigen delivery system. Such a system would enable the delivery of antigen without additional polymers. This study focused on defining the structural and cellular characteristics of nanocapsules consisting of antigen (ovalbumin) alone, synthesized by the templating method using highly monodispersed solid core mesoporous shell (SC/MS) and mesoporous (MS) silica nanoparticles of 410 nm and 41 nm in diameter, respectively. The synthesized ovalbumin nanocapsules were homogeneous in structure, and cellular uptake was observed in DC2.4 murine immature dendritic cells with minimal cytotoxicity. The nanocapsules were localized intracellularly and induced antigen presentation by the cross-presentation pathway. The templating system, using SC/MS and MS silica nanoparticles, was demonstrated to be an effective nanocapsule synthesis method for a new antigen delivery system.

C-Type lectin receptor(s)-targeted nanoliposomes: an intelligent approach for effective cancer immunotherapy

Aim: The purpose of present approach is to target C-Type lectin (CTL) receptors for preferential uptake by the macrophages/dendritic cells and improving the cross-presentation of ovalbumin. Materials & methods: Conventional and engineered nanoliposomes (MPNLs) were fabricated and extensively characterized. The nanoliposome(s) was spherical in shape; and their ζ potential, size and ovalbumin loading efficiency were recorded to be 268 ± 4.15 nm, 23.4 ± 0.35 mV, 46.65 ± 1.84%, respectively. Results: The findings demonstrate that MPNLs significantly improved the antigen uptake and its cross-presentation to evoke Th CD8+ cell-mediated cellular immunity. Conclusion: In a nutshell, this engineered approach mannose surface modification for active targeting to dendritic cells/macrophages and pH-dependent quick endosomal antigen release is a promising system for efficient cancer immunotherapy.

Nasal vaccination with poly(β-amino ester)-poly(d,l-lactide-co-glycolide) hybrid nanoparticles

Mucosal vaccination stimulates both mucosal and systemic immunity. However, mucosal applications of vaccine antigens in their free form generally result in poor systemic immune responses and need adjuvantation. In this study, bovine serum albumin loaded, new hybridised poly(β-amino ester)-poly(d,l-lactide-co-glycolide) nanoparticles were prepared by double emulsion-solvent evaporation method, characterised and evaluated in vivo as nasal vaccine carriers. Cationic spherical particles with a mean size of 240nm, good physical stability and high encapsulation efficiency were obtained. Protein structure was not affected throughout preparation and minimal toxicity was shown in Calu-3 and A549 cells. Nasal vaccination with these nanoparticles revealed markedly higher humoral immune responses compared with free antigen following intranasal and subcutaneous immunisation. Mucosal immune response was also stimulated and cytokine titres indicated that Th1 and Th2 pathways were successfully activated. This study shows that the formulated hybrid nanoparticles can be a promising carrier for nasal immunisation of poor antigenic proteins.

A Poly(Lactic-co-Glycolic) Acid Nanovaccine Based on Chimeric Peptides from Different Leishmania infantum Proteins Induces Dendritic Cells Maturation and Promotes Peptide-Specific IFNγ-Producing CD8+ T Cells Essential for the Protection against Experimental Visceral Leishmaniasis

Visceral leishmaniasis, caused by Leishmania (L.) donovani and L. infantum protozoan parasites, can provoke overwhelming and protracted epidemics, with high case-fatality rates. An effective vaccine against the disease must rely on the generation of a strong and long-lasting T cell immunity, mediated by CD4⁺ T_H1 and CD8⁺ T cells. Multi-epitope peptide-based vaccine development is manifesting as the new era of vaccination strategies against Leishmania infection. In this study, we designed chimeric peptides containing HLA-restricted epitopes from three immunogenic L. infantum proteins (cysteine peptidase A, histone H1, and kinetoplastid membrane protein 11), in order to be encapsulated in poly(lactic-co-glycolic) acid nanoparticles with or without the adjuvant monophosphoryl lipid A (MPLA) or surface modification with an octapeptide targeting the tumor necrosis factor receptor II. We aimed to construct differentially functionalized peptide-based nanovaccine candidates and investigate their capacity to stimulate the immunomodulatory properties of dendritic cells (DCs), which are critical regulators of adaptive immunity generated upon vaccination. According to our results, DCs stimulation with the peptide-based nanovaccine candidates with MPLA incorporation or surface modification induced an enhanced maturation profile with prominent IL-12 production, promoting allogeneic T cell proliferation and intracellular production of IFNγ by CD4⁺ and CD8⁺ T cell subsets. In addition, DCs stimulated with the peptide-based nanovaccine candidate with MPLA incorporation exhibited a robust transcriptional activation, characterized by upregulated genes indicative of vaccine-driven DCs differentiation toward type 1 phenotype. Immunization of HLA A2.1 transgenic mice with this peptide-based nanovaccine candidate induced peptide-specific IFNγ-producing CD8⁺ T cells and conferred significant protection against L. infantum infection. Concluding, our findings supported that encapsulation of more than one chimeric multi-epitope peptides from different immunogenic L. infantum proteins in a proper biocompatible delivery system with the right adjuvant is considered as an improved promising approach for the development of a vaccine against VL.

Platform technologies for modern vaccine manufacturing

Improved understanding of antigenic components and their interaction with the immune system, as supported by computational tools, permits a sophisticated approach to modern vaccine design. Vaccine platforms provide an effective tool by which strategically designed peptide and protein antigens are modularized to enhance their immunogenicity. These modular vaccine platforms can overcome issues faced by traditional vaccine manufacturing and have the potential to generate safe vaccines, rapidly and at a low cost. This review introduces two promising platforms based on virus-like particle and liposome, and discusses the methodologies and challenges.

The Current State of Nanoparticle-Induced Macrophage Polarization and Reprogramming Research

Macrophages are vital regulators of the host defense in organisms. In response to different local microenvironments, resting macrophages (M0) can be polarized into different phenotypes, pro-inflammatory (M1) or anti-inflammatory (M2), and perform different roles in different physiological or pathological conditions. Polarized macrophages can also be further reprogrammed by reversing their phenotype according to the changed milieu. Macrophage polarization and reprogramming play essential roles in maintaining the steady state of the immune system and are involved in the processes of many diseases. As foreign substances, nanoparticles (NPs) mainly target macrophages after entering the body. NPs can perturb the polarization and reprogramming of macrophages, affect their immunological function and, therefore, affect the pathological process of disease. Optimally-designed NPs for the modulation of macrophage polarization and reprogramming might provide new solutions for treating diseases. Systematically investigating how NPs affect macrophage polarization is crucial for understanding the regulatory effects of NPs on immune cells in vivo. In this review, macrophage polarization by NPs is summarized and discussed.

Antimicrobial Nanostructures for Neurodegenerative Infections

Nanostructures have been widely involved in changes in the drug delivery system. Nanoparticles have unique physicochemical properties, e.g., ultrasmall size, large surface area, and the ability to target specific actions. Various nanomaterials, like Ag, ZnO, Cu/CuO, and Al₂O₃, have antimicrobial activity. Basically, six mechanisms are involved in the production of antimicrobial activity, i.e., (1) destruction of the peptidoglycan layer, (2) release of toxic metal ions, (3) alteration of cellular pH via proton efflux pumps, (4) generation of reactive oxygen species, (5) damage of nuclear materials, and (6) loss of ATP production. Nanomedicine contributes to various pharmaceutical applications, like diagnosis and treatment of various ailments including microbial diseases. Furthermore, nanostructured antimicrobial agents are also involved in the treatment of the neuroinfections associated with neurodegenerative disorders. This chapter focuses on the nanostructure and nanomedicine of antimicrobial agents and their prospects for the possible management of infections associated with neurodegenerative disorders.

Vaccine Delivery Methods into the Future

Several modes of vaccine delivery have been developed in the last 25 years, which induce strong immune responses in pre-clinical models and in human clinical trials. Some modes of delivery include, adjuvants (aluminum hydroxide, Ribi formulation, QS21), liposomes, nanoparticles, virus like particles, immunostimulatory complexes (ISCOMs), dendrimers, viral vectors, DNA delivery via gene gun, electroporation or Biojector 2000, cell penetrating peptides, dendritic cell receptor targeting, toll-like receptors, chemokine receptors and bacterial toxins. There is an enormous amount of information and vaccine delivery methods available for guiding vaccine and immunotherapeutics development against diseases.