Engineered Nanoparticles inside a Microparticle Oral System for Enhanced Mucosal and Systemic Immunity.

Antigen delivery through an oral route requires overcoming multiple challenges, including gastrointestinal enzymes, mucus, and epithelial tight junctions. Although each barrier has a crucial role in determining the final efficiency of the oral vaccination, transcytosis of antigens through follicle-associated epithelium (FAE) represents a major challenge. Most of the research is focused on delivering an antigen to the M-cell for FAE transcytosis because M-cells can easily transport the antigen from the luminal site. However, the fact is that the M-cell population is less than 1% of the total gastrointestinal cells, and most of the oral vaccines have failed to show any effect in clinical trials. To challenge the current dogma of M-cell targeting, in this study, we designed a novel tandem peptide with a FAE-targeting peptide at the front position and a cell-penetrating peptide at the back position. The tandem peptide was attached to a smart delivery system, which overcomes the enzymatic barrier and the mucosal barrier. The result showed that the engineered system could target the FAE (enterocytes and M-cells) and successfully penetrate the enterocytes to reach the dendritic cells located at the subepithelium dome. There was successful maturation and activation of dendritic cells in vitro confirmed by a significant increase in maturation markers such as CD40, CD86, presentation marker MHC I, and proinflammatory cytokines (TNF-α, IL-6, and IL-10). The in vivo results showed a high production of CD4+ T-lymphocytes (helper T-cell) and a significantly higher production of CD8+ T-lymphocytes (killer T-cell). Finally, the production of mucosal immunity (IgA) in the trachea, intestine, and fecal extracts and systemic immunity (IgG, IgG1, and IgG2a) was successfully confirmed. To the best of our knowledge, this is the first study that designed a novel tandem peptide to target the FAE, which includes M-cells and enterocytes rather than M-cell targeting and showed that a significant induction of both the mucosal and systemic immune response was achieved compared to M-cell targeting.

Current status of nanoscale drug delivery and the future of nano-vaccine development for leishmaniasis - A review.

The study of tropical diseases like leishmaniasis, a parasitic disease, has not received much attention even though it is the second-largest infectious disease after malaria. As per the WHO report, a total of 0.7-1.0 million new leishmaniasis cases, which are spread by 23 Leishmania species in more than 98 countries, are estimated with an alarming 26,000-65,000 death toll every year. Lack of potential vaccines along with the cost and toxicity of amphotericin B (AmB), the most common drug for the treatment of leishmaniasis, has raised the interest significantly for new formulations and drug delivery systems including nanoparticle-based delivery as anti-leishmanial agents. The size, shape, and high surface area to volume ratio of different NPs make them ideal for many biological applications. The delivery of drugs through liposome, polymeric, and solid-lipid NPs provides the advantage of high biocomatibilty of the carrier with reduced toxicity. Importantly, NP-based delivery has shown improved efficacy due to targeted delivery of the payload and synergistic action of NP and payload on the target. This review analyses the advantage of NP-based delivery over standard chemotherapy and natural product-based delivery system. The role of different physicochemical properties of a nanoscale delivery system is discussed. Further, different ways of nanoformulation delivery ranging from liposome, niosomes, polymeric, metallic, solid-lipid NPs were updated along with the possible mechanisms of action against the parasite. The status of current nano-vaccines and the future potential of NP-based vaccine are elaborated here.

Novel vaccine design based on genomics data analysis: A review.

Modification of pathogenic strains with the passage of time is responsible for evolution in the timeline of vaccine development for last 30 years. Recent advancements in computational vaccinology on the one hand and genome sequencing approaches on the other have generated new hopes in vaccine development. The aim of this review was to discuss the evolution of vaccines, their characteristics and limitations. In this review, we highlighted the evolution of vaccines, from first generation to the current status, pointing out how different vaccines have emerged and different approaches that are being followed up in the development of more rational vaccines against a wide range of diseases. Data were collected using Google Scholar, Web of Science, Science Direct, Web of Knowledge, Scopus and Science Hub, whereas computational tools such as NCBI, GeneMANIA and STRING were used to analyse the pathways of vaccine action. Innovative tools, such as computational tools, recombinant technologies and intra-dermal devices, are currently being investigated in order to improve the immunological response. New technologies enlightened the interactions of host proteins with pathogenic proteins for vaccine candidate development, but still there is a need of integrating transcriptomic and proteomic approaches. Although immunization with genomics data is a successful approach, its advantages must be assessed case by case and its applicability depends on the nature of the agent to be immunized, the nature of the antigen and the type of immune response required to achieve effective protection.

Occurrence and possible roles of polysaccharides in fungi and their influence on the development of new technologies.

The article summarizes the roles of polysaccharides in the biology of fungi and their relationship in the development of new technologies. The comparative approach between the evolution of fungi and the chemistry of glycobiology elucidated relevant aspects about the role of polysaccharides in fungi. Also, based on the knowledge of fungal glycobiology, it was possible to address the development of new technologies, such as the production of new anti-tumor drugs, vaccines, biomaterials, and applications in the field of robotics. We conclude that polysaccharides activate pathways of apoptosis, secretion of pro-inflammatory substances, and macrophage, inducing anticancer activity. Also, the activation of the immune system, which opens the way for the production of vaccines. The development of biomaterials and parts for robotics is a promising and little-explored field. Finally, the article is multidisciplinary, with a different and integrated approach to the role of nature in the sustainable development of new technologies.

TLR2 agonists and their structure-activity relationships.

Agonists of Toll-like Receptor 2 (TLR2) are attractive synthetic targets due to their use as adjuvants in immunotherapies to treat various diseases notably, cancer. An indepth understanding of TLR2 agonist structure-activity relationships is therefore advantageous for the methodical design of vaccines targetting the TLR2 machinery. This review aims to collate and discuss the literature regarding synthetic studies towards TLR2 agonists and the structure-activity relationships thereof. It is hoped that interested readers will gain a holistic understanding of this topic, and will prompt further efforts towards finding effective agonists of TLR2.

Nanoparticles and Vaccine Development.

In spite of the progress of conventional vaccines, improvements are required due to concerns about the low immunogenicity of the toxicity, instability, and the need for multiple administrations of the vaccines. To overcome the mentioned problems, nanotechnology has recently been incorporated into vaccine development. Nanotechnology increasingly plays an important role in vaccine development nanocarrier-based delivery systems that offer an opportunity to increase the cellular and humoral immune responses. The use of nanoparticles in vaccine formulations allows not only enhanced immunogenicity and stability of antigen, but also targeted delivery and slow release. Over the past decade, nanoscale size materials such as virus-like particles, liposomes, ISCOMs, polymeric, inorganic nanoparticles and emulsions have gained attention as potential delivery vehicles for vaccine antigens, which can both stabilize vaccine antigens and act as adjuvants. This advantage is attributable to the nanoscale particle size, which facilitates uptake by Antigen- Presenting Cells (APCs), then leading to efficient antigen recognition and presentation. Modifying the surfaces of nanoparticles with different targeting moieties permits the delivery of antigens to specific receptors on the cell surface, thereby stimulating selective and specific immune responses. This review provides an overview of recent advances in nanovaccinology.

Consequence of Hapten Stereochemistry: An Efficacious Methamphetamine Vaccine.

Recent trends in methamphetamine (METH) misuse and overdose suggest society is inadvertently overlooking a brewing METH crisis. In the past decade, psychostimulant-related lethal overdoses and hospitalizations have skyrocketed 127 and 245%, respectively. Unlike the opioid crisis, no pharmaceutical interventions are available for treating METH use disorder or reversing overdose. Herein, we report the first active vaccine that offers protection from lethal (+)-METH challenge in male Swiss Webster mice. This vaccine formulation of (S)MLMH-TT adjuvanted with CpG ODN 1826 + alum successfully raised anti-METH antibodies in high titers, reduced (+)-METH distribution to the brain, and lowered (+)-METH-associated stereotypies in a hyperlocomotion assay. A comparison of enantiomeric haptens and the racemate elucidated the importance of employing (S)-stereochemistry in METH hapten design for optimal protection.

The new era of vaccines: the "nanovaccinology".

Vaccinations are the most effective preventive methods against infectious diseases and represent one of the most relevant successes of medicine. Vaccine development is constantly evolving; therefore, the number of vaccine candidates is progressively increasing. However, most of new potential vaccines are characterized by a lower immunogenicity, with the inability to stimulate powerful and long-lasting immune responses. Hence, to get modern and effective vaccines, we need adjuvants and innovative delivery systems that increase their immunogenicity. The use of nanotechnology in vaccinology is providing the opportunity to contrast these difficulties and develop effective vaccines. Particularly, nanoparticles used as vehicles of vaccine components, are able to increase the host's immune responses and, due to their size, to reach specific cellular districts. To date, a certain number of nanovaccines has been approved for human health and many are studied in clinical or pre-clinical trials. There are several types of nanoparticles considered as possible delivers of vaccine antigens. These nanoparticles-based synthetic delivery systems, in the size range of 20-200 nm, protect antigen from degradation, enhance its presentation and facilitate its uptake by professional antigen-presenting cells. Virus-like particles, self-assembled proteins, micelles, liposomes, inorganic nanoparticles, and polymers are the most studied of these systems. In this review, we provide a general overview of different types, methods of synthesis, characterizations, properties and applications of nanoparticles in vaccine production.

Analysis of Apical Membrane Antigen (AMA)-1 characteristics using bioinformatics tools in order to vaccine design against Plasmodium vivax.

Plasmodium vivax, an intracellular protozoan, causes malaria which is characterized by fever, anemia, respiratory distress, liver and spleen enlargement. In spite of attempts to design an efficient vaccine, there is not a vaccine against P. vivax. Notable advances have recently achieved in the development of malaria vaccines targeting the surface antigens such as Apical Membrane Antigens (AMA)-1. AMA-1 is a micronemal protein synthesized during the erythrocyte-stage of Plasmodium species and plays a significant role in the invasion process of the parasite into host cells. P. vivax AMA-1 (PvAMA-1) can induce strong cellular and humoral responses, indicating that it can be an ideal candidate of vaccine against malaria. Identification and prediction of proteins characteristics increase our knowledge about them and leads to develop vaccine and diagnostic studies. In the present study several valid bioinformatics tools were applied to analyze the various characteristics of AMA-1 such as physical and chemical properties, secondary and tertiary structures, B- cell and T-cell prediction and other important features in order to introduce potential epitopes for designing a high-efficient vaccine. The results demonstrated that this protein had 57 potential PTM sites and only one transmembrane domain on its sequence. Also, multiple hydrophilic regions and classical high hydrophilic domains were predicted. Secondary structure prediction revealed that the proportions of random coil, alpha-helix and extended strand in the AMA-1 sequence were 53.74%, 27.22%, and 19.4%, respectively. Moreover, 5 disulfide bonds were predicted at positions 14-21aa, 162-192aa, 208-220aa, 247-265aa and 354-363aa. The data obtained from B-cell and T-cell epitopes prediction showed that there were several potential epitopes on AMA-1 that can be proper targets for diagnostic and vaccine studies. The current study presented interesting basic and theoretical information regarding PvAMA-1, being important for further studies in order to design a high-efficiency vaccine against malaria.

Synthesis and immunological studies of ß-1,2-mannan-peptide conjugates as antifungal vaccines.

Fungal cell surface carbohydrates and proteins are useful antigens for the development of antifungal vaccines. In this study, glycopeptides consisting of the ß-1,2-mannan and N-terminal peptide epitopes of Candida albicans (C. albicans) cell wall phosphomannan complex and Als1p (rAls1p-N) protein, respectively, were synthesized and covalently conjugated with keyhole limpet hemocyanin (KLH) and human serum albumin (HSA) through homobifunctional disuccinimidyl glutarate. The resultant KLH-conjugates were immunologically evaluated using Balb/c mice to reveal that they induced high levels of IgG antibodies. Furthermore, these conjugates showed self-adjuvanting property, as they could promote robust antibody responses without the presence of an external adjuvant. More significantly, the obtained antisera could effectively recognize both the carbohydrate and the Als1 peptide epitopes and immunofluorescence and flow cytometry assays also demonstrated that the elicited antibodies could react with the cell surface of a number of fungi, including C. albicans, C. tropicalis, C. lustaniae and C. glabrata. These results suggested the great potential of these conjugates as antifungal vaccines.

Impact of branching on the conformational heterogeneity of the lipopolysaccharide from Klebsiella pneumoniae: Implications for vaccine design.

Resistance of Klebsiella pneumoniae (KP) to antibiotics has motivated the development of an efficacious KP human vaccine that would not be subject to antibiotic resistance. Klebsiella lipopolysaccharide (LPS) associated O polysaccharide (OPS) types have provoked broad interest as a vaccine antigen as there are only 4 that predominate worldwide (O1, O2a, O3, O5). Klebsiella O1 and O2 OPS are polygalactans that share a common D-Gal-I structure, for which a variant D-Gal-III was recently discovered. To understand the potential impact of this variability on antigenicity, a detailed molecular picture of the conformational differences associated with the addition of the D-Gal-III (1 → 4)-α-Galp branch is presented using enhanced-sampling molecular dynamics simulations. In D-Gal-I two major conformational states are observed while the presence of the 1 → 4 branch in D-Gal-III resulted in only a single dominant extended state. Stabilization of the more folded states in D-Gal-I is due to a O4-H⋯O2 hydrogen bond in the linear backbone that cannot occur in D-Gal-III as the O4 is in the Galp(1 → 4)Galp glycosidic linkage. The impact of branching in D-Gal-III also significantly decreases the accessibility of the monosaccharides in the linear backbone region of D-Gal-I, while the accessibility of the terminal D-Gal-II region of the OPS is not substantially altered. The present results suggest that a vaccine that targets both the D-Gal-I and D-Gal-III LPS can be developed by using D-Gal-III as the antigen combined with cross-reactivity experiments using the Gal-II polysaccharide to assure that this region of the LPS is the primary epitope of the antigen.

Weighted lambda superstrings applied to vaccine design.

We generalize the notion of λ-superstrings, presented in a previous paper, to the notion of weighted λ-superstrings. This generalization entails an important improvement in the applications to vaccine designs, as it allows epitopes to be weighted by their immunogenicities. Motivated by these potential applications of constructing short weighted λ-superstrings to vaccine design, we approach this problem in two ways. First, we formalize the problem as a combinatorial optimization problem (in fact, as two polynomially equivalent problems) and develop an integer programming (IP) formulation for solving it optimally. Second, we describe a model that also takes into account good pairwise alignments of the obtained superstring with the input strings, and present a genetic algorithm that solves the problem approximately. We apply both algorithms to a set of 169 strings corresponding to the Nef protein taken from patiens infected with HIV-1. In the IP-based algorithm, we take the epitopes and the estimation of the immunogenicities from databases of experimental epitopes. In the genetic algorithm we take as candidate epitopes all 9-mers present in the 169 strings and estimate their immunogenicities using a public bioinformatics tool. Finally, we used several bioinformatic tools to evaluate the properties of the candidates generated by our method, which indicated that we can score high immunogenic λ-superstrings that at the same time present similar conformations to the Nef virus proteins.

Recent Patents Applications in Red Biotechnology: A Mini-Review.

BACKGROUND: The different fields of biotechnology can be classified by colors, as a "rainbow" methodology. In this sense, the red biotechnology, focused on the preservation of health, has been outstanding in helping to solve this challenge through the provision of technologies, including diagnostic kits, molecular diagnostics, vaccines, innovations in cancer research, therapeutic antibodies and stem cells. OBJECTIVE: The main goal of this work is to highlight the different areas within the red Biotechnology. In this sense, we revised some patents regarding red biotechnology as examples to cover this subject. METHODS: A literature search of patents was performed from the followings Patents Database: INPI, USPTO, Esp@cenet, WIPO and Google Patents. RESULTS: Our analysis showed the following numbers from patents found: cancer research (8), diagnosis kit (9), vaccines (8), stem cells (9) and therapeutic antibodies (5), where the United States is the leader for most filled patents in Red Biotechnology. CONCLUSION: This mini-review has provided an update of some patents on Recent Patents in Red Biotechnology. As far as we know, this is the first mini-review report on Red Biotechnology based on patents.

Heat shock proteins: A dual carrier-adjuvant for an anti-drug vaccine against heroin.

Heroin is a highly abused opioid that has reached epidemic status within the United States. Yet, existing therapies to treat addiction are inadequate and frequently result into rates of high recidivism. Vaccination against heroin offers a promising alternative therapeutic option but requires further development to enhance the vaccine's performance. Hsp70 is a conserved protein with known immunomodulatory properties and is considered an excellent immunodominant antigen. Within an antidrug vaccine context, we envisioned Hsp70 as a potential dual carrier-adjuvant, wherein immunogenicity would be increased by co-localization of adjuvant and antigenic drug hapten. Recombinant Mycobacterium tuberculosis Hsp70 was appended with heroin haptens and the resulting immunoconjugate granted anti-heroin antibody production and blunted heroin-induced antinociception. Moreover, Hsp70 as a carrier protein surpassed our benchmark Her-KLH cocktail through antibody-mediated blockade of 6-acetylmorphine, the main mediator of heroin's psychoactivity. The work presents a new avenue for exploration in the use of hapten-Hsp70 conjugates to elicit anti-drug immune responses.

Designing Multivalent Ligands to Control Biological Interactions: From Vaccines and Cellular Effectors to Targeted Drug Delivery.

Multivalent interactions in which multiple ligands on one object bind to multiple receptors on another are commonly found in natural biological systems. In addition, these interactions can lead to increased strength and selectivity when compared to the corresponding monovalent interaction. These attributes have also guided the design of synthetic multivalent ligands to control biological interactions. This review will highlight the recent literature describing the use of multivalent ligand display in the design of vaccines, immunomodulators, cell signaling effectors, and vehicles for targeted drug delivery.

Preparation and Characterization of an Oral Vaccine Formulation Using Electrosprayed Chitosan Microparticles.

Chitosan particles loaded with the antigen ovalbumin (OVA) and the adjuvant Quil-A were produced by electrospray, using mixtures of water/ethanol/acetic acid as a solvent. Three different chitosans designed as HMC+70, HMC+85, and HMC+90 (called as 705010, 855010, and 905010) were tested and its efficacy to be used in oral vaccine delivery applications was investigated. The morphology, size, and zeta potential of the produced particles were investigated, together with the encapsulation efficiency and release of OVA from the three chitosan formulations. Moreover, the mucoadhesion and cytotoxicity of the chitosan microparticles was examined. All the three formulations with OVA and Quil-A were in the micrometer size range and had a positive zeta potential between 46 and 75 mV. Furthermore, all the three formulations displayed encapsulation efficiencies above 80% and the release of OVA over a period of 80 h was observed to be between 38 and 47%. None of the developed formulations exhibited high mucoadhesive properties, either cytotoxicity. The formulation prepared with HMC+70, OVA, and Quil-A had the highest stability within 2 h in buffer solution, as measured by dynamic light scattering. The electrosprayed formulation consisting of HMC+70 with OVA and Quil-A showed to be the most promising as an oral vaccine system.

[From vaccine manufacturing to its availability in pharmacy]. / De la fabrication d'un vaccin à sa mise à disposition en pharmacie.

After a brief overview of vaccine industry and the regulatory requirements for biologics, the biological and pharmaceutical manufacturing of vaccine is presented. Vaccine production specificities are discussed. They show that, despite recent efforts and progress, continuously adapting vaccine supply to demand "at any time and in any place" remains a challenge, for reasons inherent in biological production, which is a production in tight flow, structurally delicate (control of the biological hazard), and weakly reactive.

Lymph Node-Targeting Nanovaccine through Antigen-CpG Self-Assembly Potentiates Cytotoxic T Cell Activation.

Therapeutic vaccines that arouse the cytotoxic T cell immune response to reject infected cells have been investigated extensively for treating disease. Due to the large amounts of resident antigen-presenting cells (APCs) and T cells in lymph nodes, great efforts have been made to explore the strategy of targeting lymph nodes directly with nanovaccines to activate T cells. However, these nanovaccines still have several problems, such as a low loading efficiency and compromised activity of antigens and adjuvants derived from traditional complicated preparation. There are also safety concerns about materials synthesized without FDA approval. Herein, we construct an assembled nanoparticle composed of an antigen (ovalbumin, OVA) and adjuvant (CpG) to ensure its safety and high loading efficiency. The activity of both components was well preserved due to the mild self-assembly process. The small size, narrow distribution, negative charge, and good stability of the nanoparticle endow these nanovaccines with superior capacity for lymph node targeting. Correspondingly, the accumulation at lymph nodes can be improved by 10-fold. Subsequently, due to the sufficient APC internalization and maturation in lymph nodes, ~60% of T cells are stimulated to proliferate and over 70% of target cells are specifically killed. Based on the effective and quick cellular immune response, the assembled nanoparticles exhibit great potential as therapeutic vaccines.