Dissertations / Theses: 'Mucosal vaccine'

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FORTUNA, DOS REMEDIOS CATARINA. "NANOPARTICLES FOR MUCOSAL VACCINE DELIVERY." Doctoral thesis, Università degli Studi di Milano, 2018. http://hdl.handle.net/2434/565631.

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Influenza is a contagious respiratory disease often disregarded due to the mild symptoms associated with it. The economic burden that flu cases impose on health care systems is substantial, not only due to influenza pandemics, but also to required hospitalizations and the need for yearly revisions of seasonal influenza vaccines. The need for a universal influenza vaccine was already recognized by the Global Vaccine Action Plan. Currently, injection-based vaccination is the most common method for influenza immunization. However, evidence has shown that mucosal immune responses, representing an important first line of defense at these sites, since most pathogens enter the body through mucosal tissues, are most efficiently induced by administration of vaccines onto mucosal surfaces than injected vaccines. From the different mucosal tissues, the gastrointestinal tract is an attractive route to be explored for vaccination; nonetheless, oral influenza vaccines are not available yet. The intestinal homeostasis is tightly controlled by several components of the intestinal barrier, such as the mucus layer, epithelial cells with different functions and an underlying immune system that surveys the gut. Between microorganisms that normally inhabit our gut, food antigens constantly present in our diet and potential pathogens, the intestinal barrier has the difficult task of integrating external and internal signals received by different cells in order to establish the correct response, immunity or tolerance, according to the antigen. Hence, oral vaccines will encounter these same intestinal barrier components and face the same obstacles as any other oral antigen or gut microorganism. The UniVacFlu consortium is currently working to develop a new mucosal universal vaccine against influenza, exploring different immunogens, immunization routes and delivery systems. This study was undertaken to understand the potential of the influenza vaccine candidate CTA1-3M2e-DD and polysaccharidic lipidated nanoparticles (NPL) when immunization occurs through the oral route. We found that, while CTA1-3M2e-DD revealed a poor ability to cross the intestinal epithelium and target intestinal antigen-presenting cells, NPL were found to readily overcome the intestinal barrier and were found associated with both CX3CR1+ macrophages and CD103+ dendritic cells. Two different routes of NPL uptake were identified: one depends on Goblet cell-associated passages that allow the transfer of high amounts of NPL from the lumen to the intestinal lamina propria; the second relies on the direct acquisition of NPL by CX3CR1+ macrophages in Peyer’s patches by extension of trans-epithelial dendrites. Moreover, NPL as an oral vaccine vector was able to deliver the loaded antigen in the intestinal lamina propria and enhanced antigen presentation to CD4+ T lymphocytes in different organs. Despite increasing the availability of antigen, NPL did not induce tolerance towards the formulated antigen and a Th1 immune response was found at the level of the Peyer’s patches. We also identified the contribution of the starvation period in the immune response induced by the NPL formulation in our model of oral immunization. The full potential of NPL as a vaccine vector is currently being further investigated to understand its immunomodulatory properties.

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Gebril, Ayman Mohamed. "Development of a mucosal vaccine delivery system." Thesis, University of Strathclyde, 2013. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24878.

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Woodberry, Tonia. "Development of a mucosal HIV polytope vaccine /." [St. Lucia, Qld.], 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16255.pdf.

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Ye, Lilin. "FcRn mediated mucosal immunity and subunit vaccine delivery." College Park, Md.: University of Maryland, 2009. http://hdl.handle.net/1903/9815.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2009.
Thesis research directed by: Virginia-Maryland Regional College of Veterinary Medicine. Maryland Campus. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Bumgardner, Sara Ashley. "Innate Immunogenicity of Lactobacillus as a Mucosal Vaccine Vector." Thesis, North Carolina State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10110534.

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Mucosal surfaces act as functional barriers against the perpetual bombardment of foreign antigens and pathogens to the body. This barrier is maintained by homeostatic interactions between the microbiome and cells of the innate and adaptive immune system, interactions that mucosal vaccines can exploit to yield both mucosal and systemic amnestic responses to foreign antigen. The commensal lactic acid Lactobacillus spp. represent one constituent of this microbiome that has been utilized as both a homeostatic promoting probiotic and as a vaccine vector. The immune modulatory capacity of Lactobacillus spp. has been demonstrated in proof-of-principle studies utilizing lactobacilli-based vaccine vectors against several pathogens. Our laboratory has focused on the development of Lactobacillus gasseri and Lactobacillus acidophilus NCFM (NCFM) as mucosal vaccine vectors for human immunodeficiency virus-1 (HIV-1), a mucosal pathogen affecting more than 35 million people worldwide and for which no current licensed vaccine exists. As activation of innate immune receptors, including toll-like receptor (TLR), NOD-like receptor (NLR), and C-type lectin receptor (CLR), by lactobacilli have been shown to be species and strain specific, characterizing the innate receptors specific to our vectors is important for rationale vaccine design.

We first demonstrate that in addition to the previously characterized TLR2/6 activating capacity of lactobacilli, L. gasseri and NCFM activate intracellular NOD2 receptor. Co-culture of murine macrophages with L.gasseri, NCFM, or NCFM-derived mutants NCK2025 and NCK2031 elicited an M2b-like phenotype, a phenotype associated with TH2 skewing and immune regulatory function. For NCFM, this M2b phenotype was dependent on expression of lipoteichoic acid and S layer proteins, as demonstrated by the use of respective mutants, NCK2025 and NCK2031. Through the use of macrophage genetic knockouts, we identified TLR2, NOD2, and inflammasome associated caspase 1 as contributors to macrophage activation to varying degrees, with NOD2 cooperating with caspase 1 for inflammasome derived IL-1β in a pyroptosis-independent fashion. Finally, utilizing an NCFM-based mucosal vaccine with surface expression of HIV-1 Gag, we show that NOD2 signaling and the presence of an intact microbiome is required for HIV-specific IgG. We show that lactobacilli differentially utilize innate immune pathways and highlight NOD2 as a key mediator of macrophage function and antigen-specific humoral responses to a NCFM-based mucosal vaccine vector.

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Thomas, Linda D., and n/a. "Pseudomonas aeruginosa : development of a mucosal vaccine for respiratory infection." University of Canberra. Human & Biomedical Sciences, 2001. http://erl.canberra.edu.au./public/adt-AUC20061109.130804.

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Pseudomonas aeruginosa (P. aeruginosa) is a frequently isolated pathogen that causes septicaemia and chronic respiratory infection. It exhibits a higher mortality rate than other gram-negative bacteria and the need for effective immunotherapy is emphasised by the frequency of antibiotic resistance associated with this organism. Mucosal immunisation with a whole killed cell P. aeruginosa vaccine has previously demonstrated a significant immune response in both rodent studies and human trials. This study is a continuation of that research, with the major goal being the identification of a purified protein antigen that could form the basis of a mucosal vaccine against P. aeruginosa. Specifically, the aims of this study were the development of purification protocols for the isolation of previously untested protein antigens, assessment of the efficacy of these antigens to enhance bacterial clearance in an animal model of acute respiratory infection, determination of the immune parameters that are associated with the resolution of P. aeruginosa respiratory infection and finally, cloning of an identified antigen which demonstrated vaccine efficacy. Protocols were established to isolate proteins for use as antigens in immune response studies. The proteins purified in this study were Pa 13, Azurin, acyl carrier protein (ACP), Amidase, Aminopeptidase, KatA and Pa70. These proteins were used to immunise rats by intestinal intra-Peyer's patch (IPP) inoculation and intratracheal (IT) boost. The immunisation protocol employed was designed to target mucosal antigen-specific immune responses where the route of immunisation, Peyer's patch (PP) intestinal inoculation, is akin to the oral delivery of antigens to the gut-associated lymphoid tissue (96). Investigations of a previously uncharacterised antigen, Pa60, later identified this protein as the P. aeruginosa catalase, KatA. This study demonstrated enhanced bacterial clearance of both homologous and heterologous challenge following immunisation with KatA. The level of clearance demonstrated by KatA was promising when compared to that of killed whole cell immunisation. KatA was cloned and studies with the recombinant protein showed enhanced bacterial clearance commensurate with that of the native protein. Immunisations with other proteins identified four additional antigens which enhanced bacterial clearance; Pa13, Pa40, Pa45 and Pa70. Amino acid sequence analysis indicated that Pa13 may be a novel protein, whereas Pa40 was determined to be amidase and Pa45, aminopeptidase. Pa70 was not successfully sequenced. These proteins were effective in significantly enhancing bacterial clearance of homologous P. aeruginosa challenge. For KatA, Pa13 and Pa70, clearance was associated with a marked phagocytic cell recruitment. In contrast, amidase and aminopeptidase demonstrated clearance with a minimal cellular response. Proteins; azurin and ACP were non-protective, failing to clear a live P aeruginosa challenge. Analysis of the antigen-specific responses of these nonprotective proteins and comparison with those antigens which enhanced bacterial clearance were used to determine factors that may contribute to the resolution of an acute pulmonary infection. The study has demonstrated that mucosal immunisation using purified protein antigens can enhance the clearance of pulmonary infection with P. aeruginosa. It has also contributed to the understanding of immune responses to newfound antigens of P. aeruginosa and identified antigen-specific responses which confirm their potential as vaccine candidates.

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Brew, Robert. "Investigation of immune responses induced by a mucosal SIV DNA vaccine." Thesis, King's College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272140.

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Thompson, Joseph Michael Johnston Robert E. "Venezuelan equine encephalitis virus replicon particles mucosal vaccine vectors and biological adjuvants /." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,1006.

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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2007.
Title from electronic title page (viewed Dec. 18, 2007). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Microbiology and Immunology." Discipline: Microbiology and Immunology; Department/School: Medicine.

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McGuire, Carolann. "Mucosal vaccination using a crude antigen and a synthetic peptide in the Trichinella spiralis model." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285567.

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Mills, Jamie-Lee S. "Modelling natural immunity to streptococcal mucosal infections and novel approaches to vaccine delivery." Thesis, Griffith University, 2022. http://hdl.handle.net/10072/414917.

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Streptococcus pyogenes causes significant global morbidity and mortally through a range of pathologies. The most common sites of infection are the upper respiratory tract and the skin, resulting in pharyngitis and impetigo respectively. Non-invasive infections are usually self-limiting; however, they have the potential to progress to life threatening invasive diseases such as toxic-shock syndrome and necrotizing fasciitis with a high rate of mortality. Furthermore, S. pyogenes infections can give rise to auto-immune sequelae of ARF/RHD and ASPGN that result in approximately 500 000 deaths each year. Despite global efforts that span decades, no human vaccine is approved for use. The major hurdles in vaccine development are the broad serotypic and antigenic diversity of S. pyogenes, the risk for potential auto-immune disease due to the molecular mimicry of the S. pyogenes M-protein (a prime vaccine target) and human cardiac myosin, and the ability of S. pyogenes to infect different body sites that require different protective immune mechanisms. Previous research has shown that exposure to S. pyogenes can result in protective antibodies, though immunity is slow to develop and its role in preventing subsequent infections is poorly understood. In addition, there is a need to understand the mechanism of cross-compartment immunity to aid in guiding vaccine development to protect from multiple serotypes and also at various infection sites. To understand the mechanisms involved in site-specific and cross-compartment immunity, repeated mucosal exposures to S. pyogenes non-lethal infections in mice were performed to mimic endemic settings. Repeated homologous mucosal infections resulted in significant site-specific protection that endured for at least 9 weeks. Mice developed type-specific serum antibodies and antibody secreting cells (ASCs) that increased with increasing number of infections. These data indicate that the longevity of the antibody response is governed by the number of prior mucosal infections; however, no direct correlation with protection was established. Mucosal protection indicated a role for cell-mediated immunity. Repeated acute mucosal infections resulted in significant neutrophil recruitment to the local site of inflammation that correlated with protection. Cytokine analysis suggested a role for IL-17A in mucosal protection, particularly for enduring protection. To assess the importance of IL-17, IL-17 knockout (IL-17-/-) mice were given repeated homologous mucosal infections. Unlike wild type BALB/c mice, IL-17-/- mice failed to generate mucosal protection with repeated exposures. Furthermore, IL-17-/- mice had significantly reduced M-protein type-specific salivary IgG, IgG and IgA-secreting cells in bone marrow, and neutrophil influx to the lung, correlating with lack of protection. Mice required only one prior mucosal infection to develop significant and long-lasting protection against a homologous mucosal challenge. However, when cross-compartment protection at the skin was assessed, mice required a minimum of four repeated mucosal infections to generate significant protection. These data suggest that developing a protective immune response by repeated exposures is unlikely in a real-world setting. The literature indicates that multiple different S. pyogenes types move through communities, and people rarely encounter the same strain again within a short period of time. Realising these constraints in developing naturally acquired immunity to S. pyogenes, the next question was then asked: ‘could vaccine mediated immunity be boosted and broadened via natural exposures to S. pyogenes?’ Vaccine candidates based on the conserved C-terminal region of S. pyogenes M-protein (p145) have made considerable progress. The C-terminal region of the M protein is conserved across the majority of S. pyogenes strains, therefore forgoing the issue of serotype diversity. Two vaccine epitopes at the forefront of development, J8 and p*17, when conjugated to the carrier protein, diphtheria toxoid (DT), create J8-DT and p*17-DT. p*17-DT delivered intramuscularly with the adjuvant, alum, (p*17-DT/Alum) has shown promising immunogenicity and protection against several S. pyogenes isolates; however, it does not protect mice against intranasal challenge with a hypervirulent covR/S mutant strain. To test the hypothesis that infection will boost vaccine-mediated immunity, mice received two vaccinations with p*17-DT/Alum, followed by repeated mucosal infections every three weeks with heterologous isolates. Mice that received vaccinations followed by sequential infections showed increasing protection against NALT (nasal associated lymphoid tissue) bacterial load with each subsequent infection when compared to naïve mice. Bacterial load in the NALT was significantly reduced in these mice following a covR/S mutant challenge. Antigen-specific ASCs were assessed as a determinant of humoral immunity. Although no increase in serum antibody levels or antibody avidity were observed between mice that received vaccination alone or when followed by repeated infections, the mice that received vaccination and sequential infections had significantly increased IgG secreting cells in the spleen. The ASCs, in combination with lung specific CD4+ T-cell responses may be contributing to increased protection seen in mice that were boosted with repeated heterologous infections. Although promising, the results were scattered, which may be attributed to the differences in sequence homology of p145 as well as characteristics of different isolates. These data suggest that vaccine-mediated immunity has the potential to be boosted with repeated exposures to S. pyogenes. However, it was demonstrated that there is room for improvement in vaccination strategy and alternative approaches should be explored. Therefore, the next aim was to assess if new delivery methods could be used to increase vaccine-mediated immunogenicity and protection. Different methods of vaccine delivery can invoke varied immune responses. Skin-based immunisation routes have gained attention due to targeting of the epidermis and dermis layers rich in immune cells. Several advantages are associated with cutaneous routes, particularly when using high density/micro array patches (MAPs and HD-MAPs). These include dose sparing, enhanced thermostability, ease of administration, reduced generation of sharp-waste and risk of needle-stick injuries, good tolerability and enhanced acceptability in patients. HD-MAPs, developed by Vaxxas Pty Ltd, are at an advanced stage of development and have shown promising clinical trials results. The aim of his final study was to determine if the M-protein-based vaccine candidate J8-DT would have comparable immunogenicity and protection if delivered on the adjuvant free HD-MAP in comparison to intramuscular delivery. The effect of dose sparing and the number of vaccinations on the antibody response profile of vaccinated mice were assessed. A reduction in the number of vaccinations (from three to two) with J8-DT/HD-MAP induced comparable antibody responses to three vaccinations with intramuscular J8-DT/Alum. J8-DT/HD-MAP vaccination led to a significant reduction in the number of S. pyogenes colony forming units in skin (92.9%) and blood (100%) compared to intramuscular vaccination with unadjuvanted J8-DT when assessed following skin challenge. J8-DT/HD-MAP induced a shift in the antibody isotype profile, with a bias towards Th1-related isotypes, compared to J8-DT/Alum (Th2 bias). Based on the results of this study, the use of J8-DT/HD-MAP should be considered in future clinical development and control programs against S. pyogenes. The studies in this thesis demonstrate the constraints in developing naturally acquired immunity and highlight the importance for developing an effective vaccine against S. pyogenes.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Institute for Glycomics
Science, Environment, Engineering and Technology
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O’Meara, Connor Patrick. "The development of an effective vaccine against Chlamydia : utilisation of a non-toxic mucosal adjuvant to generate a protective mucosal response." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/61614/1/Connor_O%27Meara_Thesis.pdf.

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Chlamydia is responsible for a wide range of diseases with enormous global economic and health burden. As the majority of chlamydial infections are asymptomatic, a vaccine has greatest potential to reduce infection and disease prevalence. Protective immunity against Chlamydia requires the induction of a mucosal immune response, ideally, at the multiple sites in the body where an infection can be established. Mucosal immunity is most effectively stimulated by targeting vaccination to the epithelium, which is best accomplished by direct vaccine application to mucosal surfaces rather than by injection. The efficacy of needle-free vaccines however is reliant on a powerful adjuvant to overcome mucosal tolerance. As very few adjuvants have proven able to elicit mucosal immunity without harmful side effects, there is a need to develop non-toxic adjuvants or safer ways to administered pre-existing toxic adjuvants. In the present study we investigated the novel non-toxic mucosal adjuvant CTA1-DD. The immunogenicity of CTA1-DD was compared to our "gold-standard" mucosal adjuvant combination of cholera toxin (CT) and cytosine-phosphate-guanosine oligodeoxynucleotide (CpG-ODN). We also utilised different needle-free immunisation routes, intranasal (IN), sublingual (SL) and transcutaneous (TC), to stimulate the induction of immunity at multiple mucosal surfaces in the body where Chlamydia are known to infect. Moreover, administering each adjuvant by different routes may also limit the toxicity of the CT/CpG adjuvant, currently restricted from use in humans. Mice were immunised with either adjuvant together with the chlamydial major outer membrane protein (MOMP) to evaluate vaccine safety and quantify the induction of antigen-specific mucosal immune responses. The level of protection against infection and disease was also assessed in vaccinated animals following a live genital or respiratory tract infectious challenge. The non-toxic CTA1-DD was found to be safe and immunogenic when delivered via the IN route in mice, inducing a comparable mucosal response and level of protective immunity against chlamydial challenge to its toxic CT/CpG counterpart administered by the same route. The utilisation of different routes of immunisation strongly influenced the distribution of antigen-specific responses to distant mucosal surfaces and also abrogated the toxicity of CT/CpG. The CT/CpG-adjuvanted vaccine was safe when administered by the SL and TC routes and conferred partial immunity against infection and pathology in both challenge models. This protection was attributed to the induction of antigen-specific pro-inflammatory cellular responses in the lymph nodes regional to the site of infection and rather than in the spleen. Development of non-toxic adjuvants and effective ways to reduce the side effects of toxic adjuvants has profound implications for vaccine development, particularly against mucosal pathogens like Chlamydia. Interestingly, we also identified two contrasting vaccines in both infection models capable of preventing infection or pathology exclusively. This indicated that the development of pathology following an infection of vaccinated animals was independent of bacterial load and was instead the result of immunopathology, potentially driven by the adaptive immune response generated following immunisation. While both vaccines expressed high levels of interleukin (IL)-17 cytokines, the pathology protected group displayed significantly reduced expression of corresponding IL-17 receptors and hence an inhibition of signalling. This indicated that the balance of IL-17-mediated responses defines the degree of protection against infection and tissue damage generated following vaccination. This study has enabled us to better understand the immune basis of pathology and protection, necessary to design more effective vaccines.

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Grieves, Jessica Louise. "Respiratory Syncytial Virus: Rodent Models and Vaccine Development." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354147313.

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Vazquez, Thomas. "Evaluation préclinique d'un protocole vaccinal anti-VIH utilisant des pseudo-particules rétrovirales recombinantes administrées par voies muqueuses et étude des mécanismes immunologiques associés." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066321.

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Malgré 30 ans de recherche aucun vaccin VIH n'a permis d'apporter une protection efficace et de manière stable. Au regard des échecs obtenus jusqu'à présent, de nouvelles formes vaccinales ont été développées. Parmi ces dernières les VLP présentent l'avantage notables d'être très immunogènes du fait de leur forme particulaire mimant les virus natifs, et sécuritaire puisque ne véhiculant pas de génome viral. Ce travail de thèse a pour objectif d’établir et d’évaluer une stratégie vaccinale utilisant ces VLP administrées par voies muqueuses dans le but d’initier une réponse humorale et cellulaire au niveau systémique et muqueux. Dans cette étude, nous avons montré que la voie muqueuse est indispensable pour l’induction d’une réponse locale forte. De plus, nos résultats révèlent que la forme particulaire de l’antigène est décisive dans la génération d’une immunité de qualité, générant une réponse TFH forte, une réponse cellulaire locale polyfonctionnelle ainsi qu’une réponse humorale forte et stable dans le temps, caractérisée par des anticorps de qualité.Cherchant à mieux caractériser la stratégie vaccinale établie, nous avons analysé les mécanismes de prise en charge des VLP et d’initiation de la réponse immunitaire après administration IN. Nous avons observé que de nombreuses cellules de l’immunité innée pulmonaire, notamment les macrophages alvéolaires et les neutrophiles, captaient massivement les VLP limitant alors la réponse TFH et potentiellement la réponse humorale qui en découle. Au final, ce travail de thèse aura permis de mettre en avant la voie d’immunisation muqueuse ainsi que la forme particulaire de l’antigène dans la mise en place d’un vaccin VIH
Currently no HIV vaccine elicit full and stable protection against viral acquisition. In view of the failures until now, new vaccines strategies were developed. Among these, VLP have the advantage to be highly immunogenic because of their particulate structure mimicking native pathogens and safe because of the lack of viral genome.This thesis work aims to develop and evaluate a VLP-based vaccine strategy by mucosal administration in order to initiate systemic and local humoral and cellular responses. In this study, we showed that the mucosal administration is mandatory to generate a strong local immunity. Moreover, our results show that particular form of the antigen is crucial in the generation of the quality of the immune response, generating strong TFH response, polyfunctional T-cell responses in the mucosa and a strong and stable humoral response characterized by high-quality antibodies.We also investigated mechanisms involved in the generation of immune responses following IN VLP injections. We determined which cells take in charge VLP and their role in the followed immune responses. Our preliminary results show many innate immune cells in the lungs, such as alveolar macrophages and neutrophils, have an important role in the particles uptake, limiting TFH response and potentially the followed humoral response.Finally, this thesis work will show the determining role of the mucosal route of immunization and the particulate form antigen for the development of an HIV vaccine

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Tyrer, Peter Charles, and n/a. "Targeting M-cells for oral vaccine delivery." University of Canberra. Health Sciences, 2004. http://erl.canberra.edu.au./public/adt-AUC20060427.122012.

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An in vitro model of the follicle-associated epithelia that overlie the Peyer's patches of the small intestine was developed and validated to examine the mechanisms of mucosal antigen sampling. This model displays many phenotypic and physiological characteristics of M cells including apical expression of [alpha]5[beta]l integrin and enhanced energy dependent participate transport. CD4+ T-cells were shown to be an important influence on the development of Mlike cells. The model was used to examine the M cell mediated uptake of several putative whole-cell killed bacterial vaccines. Greater numbers of non-typeable Haemophilus influenzae NTHi 289, NTHi 2019, Escherichia coli 075 HMN and Streptococcus pneumoniae were transported by model M cells compared to control Caco-2 enterocyte-like cells. Studies in isolated murine intestine segments confirmed the selective uptake of NTHi 289 and Escherichia coli demonstrating that intestinal mucosal sampling of these antigens is performed by M cells. Pseudomonas aeruginosa was not absorbed as whole cell bacteria but as soluble antigen, as indicated by the presence of bacterial DNA in the cytoplasm of epithelial cells. These results suggest that bacteria such as NTHi and E. coli are sampled by the mucosal immune system in a different manner to that of bacteria such as Pseudomonas. A number of potential cell surface receptors were investigated to identify which molecules are responsible for intestinal uptake whole-cell killed bacteria. Immunofluorescence studies detected the presence of toll-like receptor-2, toll-like receptor-4, PAF-R and [alpha]5[beta]l integrin on in vitro M-like cell cultures. Examinations of murine intestine confirmed the presence of TLR-4 and PAF-R. TLR-4 was found in small quantities and on M cells. In contrast to the M cell model, TLR-2 expression in the murine intestine was sparse. Receptor inhibition experiments provided evidence for the involvement of TLR-4, PAF-R and [alpha]5[beta]l integrin in M cell uptake of killed bacteria both in vitro and in vivo. This thesis has contributed valuable information regarding the mechanisms of uptake of whole-cell killed bacteria by the intestinal mucosal immune system. For the first time, M cell sampling of whole-cell killed bacteria has been demonstrated. Furthermore, the receptors involved in these processes have been identified. This information will be of great use in the development and optimisation of new oral vaccines.

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CIRELLI, ELISA. "Co-adjuvant effect of retinoic acid in combination with systemic adjuvants on mucosal vaccine immunization." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2014. http://hdl.handle.net/2108/203188.

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La grande maggioranza dei patogeni invade l’ospite o causa malattie attraverso le mucose. Lo sviluppo di nuove strategie di immunizzazione per indurre risposte immunitarie a livello delle mucose è ampiamente richiesto. Attualmente, sono disponibili pochi vaccini mucosali, nessuno dei quali è costituito da proteine ricombinanti o subunità di patogeni, questo principalmente a causa della mancanza di adiuvanti mucosali potenti e sicuri. Dato il ruolo cruciale dei metaboliti della vitamina A, come l’acido retinoico (RA), nel conferire alle cellule del sistema immunitario la capacità di migrare nei distretti mucosali, e di promuovere il differenziamento di cellule che producono IgA, i metaboliti della vitamina A sono potenziali molecole candidate per migliorare le risposte immunitarie a livello delle mucose. In questo studio, sono state investigate nuove strategie di immunizzazione per amplificare le risposte immunitarie sia sistemiche che mucosali tramite la somministrazione di RA. In una prima fase, abbiamo osservato che il trattamento con RA sinergizza con la tossina colerica (CT), nell’aumentare le risposte antigene (Ag)-specifiche mucosali e sistemiche in seguito ad un’immunizzazione intranasale. Nel corso di questi esperimenti, abbiamo osservato che la somministrazione dell’Ag intranasale in assenza di adjuvante era in grado di generare una risposta a livello mucosale in topi che erano stati trattati con RA. Ci siamo quindi chiesti se tale risposta potesse essere amplificata in seguito ad un boost sistemico con l’Ag in combinazione con un adjuvante sistemico. Abbiamo osservato che la combinazione di un priming mucosale con Ag da solo, seguito da un boost sistemico con Ag e Alum, induce risposte mucosali e sistemiche durevoli nel tempo. In una seconda fase, abbiamo valutato gli effetti della somministrazione di RA in concomitanza con una vaccinazionsistemica utilizzando un vaccino a subunità contro la tubercolosi. Tale vaccino è composto da un adjuvante sistemico CAF01 e da un Ag di fusione derivato da tre proteine antigeniche di Mycobacterium tuberculosis (Mtb), H56. Abbiamo osservato che il trattamento con RA promuove la risposta anticorpale Agspecifica sia sistemica (IgG) che mucosale (IgA) e determina la colonizzazione dei distretti mucosali da parte dei linfociti T CD4+ Ag-specifici. Infine, abbiamo valutato gli effetti di RA sulla protezione verso un challenge con il ceppo virulento di Mtb (H37Rv) di topi immunizzati con il vaccino a subunità CAF01/H56. Abbiamo osservato che l’immunizzazione sistemica con CAF01 e H56 in presenza di RA ha un impatto sul contenimento della crescita di Mtb a livello polmonare 14 giorni dopo l’infezione. Inoltre, è stata rilevata una più alta produzione di citochine pro-infiammatorie nei polmoni di topi immunizzati con CAF01 e H56 24 ore dopo l’infezione. In conclusione, questo approccio che ha lo scopo di generare le risposte a livello sistemico ed indirizzarle nei distretti mucosali utilizando modulatori della migrazione cellulare come l’RA, potrebbe contribuire a far progredirela ricerca degli adiuvanti. Risposte mucosali potrebbero essere generate utilizzando gli adiuvanti sistemici disponibili in assenza di adiuvanti mucosali.
The vast majority of pathogens invade the host through or cause disease at mucosal surfaces. Development of novel immunization strategies suitable for mucosal vaccines is widely desired to protect against infectious diseases. However, very few mucosal vaccines are available for human use, none of which are recombinant proteins or subunits of pathogens, owing to the lack of potent and safe mucosal adjuvants. Given the crucial role of Vitamin A metabolites, such as retinoic acid (RA) in imprinting a mucosal homing capacity on T and B cells, as well as its potential to promote the differentiation of IgA-producing plasma cells, RA holds potential as a candidate molecule to improve mucosal vaccinations. In this study, we investigated new strategies of immunization to amplify both systemic and mucosal immune responses by administering RA. First, we observed that treatment with RA synergises with the adjuvant capacity of cholera toxin (CT) to enhance both systemic and mucosal Ag-specific immune responses. The combination of mucosal priming with Ag alone, followed by a boost with systemic adjuvant was also evaluated. Mice treated with RA showed a higher titer of mucosal IgA compared to untreated mice, after intranasal priming with Ag followed by a systemic boost with Ag plus Alum. After eight months, higher IgG Ag-specific antibodies in the serum and a higher frequency of Ag-specific IgG and IgA secreting cells were detected in the bone marrow of mice treated with RA as compared to untreated mice. Higher percentages of proliferating CD4 and CD8 T cells upon Ag stimulation were found in the spleens, in the mesenteric lymph nodes and in the colonic lamina propria of mice treated with RA. Next, we evaluated the effects of RA on systemic vaccination with a subunit vaccine against tuberculosis. This vaccine includes CAF01 as adjuvant and the mycobacterial derived fusion protein H56. We found that mice treated with RA as compared with untreated ones, showed enhanced mucosal (IgA) H56 mycobacterial fusion proteinspecific antibody responses and enhanced Ag-specific CD4+ T lymphocytes harbouring the lung after systemic immunization with the TB subunit vaccine. Therefore, we evaluated the effects of RA on protection against challenge with virulent Mycobacterium tuberculosis (Mtb) strain after systemic vaccination with the TB subunits vaccine (CAF01 and H56). Vaccination with BCG was included in the experiment as control. We found that immunization with CAF01 and H56 in presence of RA leads to a lower bacterial colonization in the lungs 14 days after challenge as compared to control mice. Furthermore, higher pro-inflammatory cytokine production, such as IFNγ and IL-17 was found in the lung of mice immunized with CAF01 and H56 in presence of RA 24h after Mtb infection. Therefore, we hypothesize that the mucosal immune responses elicited during vaccination in presence of RA could have an impact on the containment of bacterial growth in the lungs. This approach can contribute to progress beyond the state of the art in adjuvant research by achieving mucosal immunity in the absence of mucosal adjuvants.

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Junior, Andrés Jimenez Galisteo. "Toxoplasma gondii vs radiação ionizante: imunidade humoral e celular em baço e intestino de camundongos isogênicos imunizados com taquizoítos irradiados por Cobalto 60." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-17082009-173434/.

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Toxoplasma gondii vs radiação ionizante: Imunidade humoral e celular em baço e intestino de camundongos isogênicos imunizados com taquizoítos irradiados por Cobalto 60 Andrés Jimenez Galisteo Jr. Estudamos o desenvolvimento de uma vacina para toxoplasmose utilizando a radiação ionizante como ferramenta. Aqui avaliamos o desenvolvimento da imunidade sistêmica e intestinal e a resistência à infecção, em diferentes camundongos imunizados, por via oral e parenteral, com taquizoítos irradiados a 255 Gy e desafiados com cistos da cepa ME49. Camundongos C57Bl/6j, BALB/c e C57Bl/6j IFN--/- foram imunizados com 107 taquizoitos de T. gondii irradiados a 255Gy por diferentes vias. As preparações de taquizoítos irradiados, por via oral e parenteral, induziram produção de imunoglobulinas IgG e IgA no soro de camundongos, sendo predominante a subclasse de IgG2b, determinadas por ELISA. A produção de IgM foi mínima. Os animais imunizados pela via parenteral, apresentaram uma maturação mais rápida da avidez de anticorpos IgG que os animais imunizados por via oral. Houve excreção de IgG, IgA e IgM nas fezes dos animais imunizados, mais intensa nos animais imunizados por via oral. No estudo da imunidade celular induzida por antígeno e detectada for real-time PCR, houve uma grande produção de IFN- por células esplênicas, menor por células das placas de Peyer intestinais, onde houve maior produção de IL-2. Houve proteção em todos os nossos esquemas avaliados, maior nos animais BALB/c. Os animais deficientes de IFN-, não foram afetados pelo processo de imunização e apresentaram produção de IgG e IgA sérico e excreção de S-IgA e S-IgM nas fezes, com menor numero de cistos cerebrais em animais imunizados por via parenteral. Todos nossos dados apontam para a possibilidade do desenvolvimento de uma vacina oral para toxoplasmose, utilizando taquizoítos irradiados, com aplicação prática na imunização de felinos domésticos e selvagens.
We are developing a vaccine for toxoplasmosis, using ionizing radiation as a tool. Here we analyzed the production of sytemic and intestinal immunity, with protection studies, in several strains of inbred mice, by oral or parenteral route, using 255 Gy irradiated tachyzoites of T. gondii RH strain, with challenge with cysts of ME- 49 strain. C57Bl/6j, BALB/c and C57Bl/6j IFN--/- mice were immunized with 107 irradiated tachyzoites, be parenteral or oral route. Those preparations, both by parenteral or oral routes, induced the production of specific IgG, mainly of the IgG2b subclass, and IgA immunoglobulins in serum, , as determined by ELISA. IgM production was negligible. Parenteral immunized mice showed higher IgG avidity maturation, as compared to oral immunized mice. Fecal excretion of IgG, IgA and IgM was detected in stools of immunized animals, more intense in oral immunized mice. In cellular immunity studies, induced by antigen, with detection of cytokine production by quantitative real-time PCR, there are a great production of IFN- by spleen cells, with lower levels in Peyer patches cells, where there are a greater IL-2 production. Challenge studies in immunized mice demonstrated protection to infection in all used schedules, greater in BALB/c mice. C57Bl/6j IFN--/- mice, when immunized, showed no signs of disease and produced similar or greater levels of antibodies than wild type mice. They also excreted S-IgA and S-IgM in stools, but with low numbers of brain cysts in parenteral immunized mice, despite similar mortality. Our data points to a fair possibility of use of those irradiated parasites as an oral vaccine, devised to use for veterinary or wild felines vaccination, reducing the production of oocysts by those hosts and interrupting the chain transmission of human toxoplasmosis.

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Xu, Lin. "HIV-1 mucosal immunity : from infection to prevention : HIV-1 envelope gp41 conserved region P1 modulates the mucosal innate immune response and acts as a potential mucosal adjuvant The HIV-1 viral synapse signals human foreskin keratinocytes to secrete thymic stromal lymphopoietin facilitating HIV-1 foreskin entry By shaping the antigen binding site in IgA, the CH1α domain is crucial for HIV-1 protection in highly exposed sero-negative individuals The antigen HIV-1 envelope gp41 conserved region P1 can act as mucosal adjuvant by modulating the innate immune response." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCB071.

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La vaccination muqueuse, notamment celle administrée par voie nasale, est considérée comme la méthode optimale permettant de protéger les sites muqueux de l'infection par des pathogènes. Cependant, le manque d'adjuvants muqueux spécifiques ainsi qu'une prise en compte insuffisante du système immun nasal limite le développement des vaccins muqueux. P1, un domaine conservé de gp41, la glycoprotéine d'enveloppe du VIH-1, a été récemment utilisé par le laboratoire d'acceuil pour développer un vaccin prophylactique muqueux après immunisation combinée par voie nasale et intra-musculaire. Ce vaccin s'est montré efficace lors études pré-cliniques et clinique de Phase I chez l'Homme, grâce à sa capacité d'induire des IgA muqueux contre P1 bloquant la pénétration muqueuse du VIH-1 par transcytose et de stimuler la production d'IgG spécifiques de gp41 induisant la lyse des cellules infectées par le VIH-1 par cytotoxicité cellulaire médiée par anticorps (ADCC). Dans le travail présenté ici, nous avons caractérisé les mécanismes immuns induits par ce vaccin basé sur P1 au niveau de la muqueuse nasale humaine. Tout d'abord, nous avons démontré que P1 initie une réponse immune en induisant la sécrétion de la cytokine TH2, la Thymic Stromal LymphoPoietin (TSLP), par les cellules épithéliales nasales. TSLP est connyu pour ses propriétés d'adjuvant muqueux puissant et son récepteur, le TSLP-R, joue un rôle déterminant dans la réponse muqueuse à IgA. Nous avons montré que P1 induit l'expression de TSLP via l'interaction de P1 avec le galactosyl céramide, un récepteur du VIH-1 permettant l'entrée muqueuse du virus. De plus, nous avons identifié la voie de signalisation Calcineurin/NFATet le microRNA- comme partenaire décisifs dans la régulation de la production de TSLP induite par P1. Dans un second temps, nous avons montré que le peptide P1 module la réponse innée en activant les cellules dendritiques (DCs). Cette stimulation par P1 induit l'augmentation de l'expression des molécules de co-stimulation par les DCs. La sécrétion de l'IL-6 et de l'IL-10 par les DCs est aussi augmentée par P1 alors que celle de l'interféron gamma, IFN-', est réduite, démontrant ainsi que les DCs activée par P1 se polarisent en une phénotype facilitant une réponse Th2 et IgA. De plus, l'IL-8 et les chimiokines CCL20 et CCL22 sont secrétées indiquant que les DCs ont acquis la capacité de recruter des cellules immunes dans la muqueuse pour initier une réponse muqueuse adaptative. La métalloprotéinase MMP-9 permettant la dégradation de la matrice extracellulaire et facilitant la migration des cellules hors de la muqueuse, est aussi produite. Une boucle positive autocrine de TSLP est observée, puisque P1 induit la sécrétion par les DCs de TSLP en conséquence l'augmentation de l'expression du TSLP-R par les DCs induite par P1. Finalement, P1 active la prolifération des lymphocytes TCD4+ médiée par les DCs. En conclusion, nous avons démontré que P1 est un peptide multifonctionnel avec un grand potentiel dans le développement de vaccin, non seulement comme antigène vaccinal candidat mais aussi comme potentiel adjuvant qui pourrait être combinés à d'autres vaccins muqueux
Mucosal vaccination, especially intranasal administrated ones, has been considered to be ideal for protection from pathogens invading through mucosal sites. However, the lack of specific adjuvant and insufficient acknowledgement of nasal immune system limits the development of vaccine. P1, a conserved region of gp41 envelope glycoprotein, was recently developed into a prophylactic HIV-1 vaccine immunized via both the intramuscular and intranasal routes. It showed high efficiency in pre-clinical and phase I clinical trial due to induction of P1 specific mucosal IgA with transcytosis blocking activity and IgG inducing antibody dependent cell cytotoxicity. In this study, we characterized the immunological mechanism underneath P1-vaccine in nasal mucosa. Firstly, we demonstrated that P1 initiate immune responses by inducing nasal epithelial cells to secret the Th2 cytokine Thymic Stromal LymphoPoietin (TSLP). TSLP has been reported to be a strong mucosal adjuvant, and its receptor TSLP-R plays a critical role in IgA response. We showed that P1 induce TSLP expression via the interaction with galactosyl ceramide, the receptor of HIV-1 mucosal entry. Furthermore, we identified Calcineurin/NFAT signaling pathway and microRNA-4485 as important players in the regulation of TSLP production induced by P1. Secondly, we showed that P1 modulates innate immune responses by activate dendritic cells (DCs). P1 stimulation results in enhanced expression of costimulatory molecules on DCs. Furthermore, the secretion of IL-6, IL-10 were increased, while IFN-γ was reduced, indicating that P1 activated DCs polarize into a Th2 and IgA prone phenotype. In addition, IL-8, CCL20, CCL22 were produced indicating a capacity at recruiting immune cells to mucosal surface for initiation of an adaptive immune response. MMP-9 was also produced allowing degradation of the extracellular matrix and facilitating the migration of immune cells out of the mucosa. Stricingly, a TSLP autocrine loop was observed as P1 induced DCs to secret TSLP and meanwhile, enhanced DC expression of TSLP-R. Finally, P1 activated DCs enhanced the proliferation of CD4+ T cells. In conclusion, we demonstrated that P1 is a multi-functional protein with a great interest for vaccine development, not only as an antigen for vaccine candidate, but also as a potential adjuvant that can be combined to other mucosal vaccines

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Shirreff, Lisa M. "Characterization of an M. marinum Vaccine| Examination of Both Mucosal Immunity and Systemic Immunity in a Fish Model." Thesis, University of Louisiana at Lafayette, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10163372.

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Mycobacterium marinum (Mm) shares at least 80% amino acid sequence identity with over 3,000 orthologous genes of Mycobacterium tuberculosis (Mtb) and is thus used as a surrogate pathogen for Mtb research. Our laboratory investigates mycobacteriosis using Japanese medaka ( Oryzias latipes) as an aquatic animal model. Mm disease presentation in medaka is similar to Mtb disease presentation in humans, including growth in macrophages, granulomatous lesions, and lifelong chronic disease. We have previously shown that a major route of infection in fish is through an oral route and have thus developed methods to infect medaka with Mm utilizing mosquito larvae as vectors. Recently, our lab was able to show that Mm is able to cross the gut epithelia of medaka in a relatively short-time frame and travel to the underlying submucosa. Therefore, Mm must have the ability to attach to the gut mucosal layer and evade killing by GALT immune cells. Mm is apparently able to exploit macrophages of the mucosal immune system to transport the bacteria to target organs like the head kidney, liver, and spleen for a systemic infection. Utilizing an Mm strain engineered to carry a deletion in the RD-1 region, known to include a number of virulence genes, our lab has shown that mucosal immunity against Mm can be induced in medaka. We have shown that exposure to the mutant RD-1 strain offers some protection against a chronic wild-type oral challenge. Since we know that mutant RD-1 can elicit a mucosal immune response, I tested to see if sensitizing mucosal immunity would also induce systemic immunity by first priming fish with mutant RD-1 and then subsequently challenging them with wild type Mm via an IP route. This thesis demonstrates that mucosal immunity is limited to the gut and thus does not appear to provide broad systemic immunity. Additionally, I tested to see if systemic vaccination would protect against a systemic virulent wild-type challenge by vaccinating and challenging fish via an IP route of infection. Results showed that systemic vaccination does not induce systemic immunity and thus does not protect against an IP injected virulent challenge. Collectively, results from this thesis have shown mutant RD-1 to only be effective as a vaccine against mycobacteriosis if given orally since it was shown to only induce a mucosal immune response and only be protective against an oral virulent wild type challenge.

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Pereau, Buffin Sophie. "Évaluation des pseudo-particules grippales dans un but de vaccination par voies muqueuses." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1087.

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Le virus de la grippe infecte les muqueuses du tractus respiratoire. Un vaccin intranasal induit une réponse immunitaire proche de celle faisant suite à une infection naturelle en bloquant le virus directement sur le site de l'infection et permet une vaccination sans aiguille. Par ailleurs, les vaccins à base de pseudo-particules virales ou Virus-like Particles (VLP) produites sur cellules représentent une alternative intéressante au vaccin classique produit sur oeufs. Les VLP sont des particules non-réplicatives qui ressemblent au virus et qui peuvent être immunogènes même sans adjuvant, en particulier par voie intranasale. Au cours de ma thèse, une plateforme de production de VLP grippales composées d'hémagglutinine, de neuraminidase et de protéine de matrice M1 a été développée par transfection transitoire des cellules de mammifères. Des immunisations de souris BALB/c ont montré que les VLP de type A et B, purifiées et caractérisées, étaient immunogènes à de faibles doses par voie intramusculaire. L'administration par voie intranasale de VLP avec la sous-unité B de la toxine cholérique, comme adjuvant muqueux, a permis d'obtenir des taux d'anticorps sériques comparables à ceux obtenus par immunisation en intramusculaire mais également une forte réponse IgA au niveau des muqueuses. Par ailleurs, le rendement des VLP s'est révélé souche-dépendant et lié aux protéines HA et NA à la surface de la particule. Pour contourner ce problème, un vaccin quadrivalent composé de deux VLP bivalentes exprimant chacune deux HA et NA différentes à la surface a été produit montrant ainsi la flexibilité de cette plateforme
The influenza virus infects the mucous membranes of the respiratory tract. An intranasal vaccine induces an immune response close to the one induced by the natural infection by blocking the virus directly at the site of infection and allows needle-free vaccination. In addition, vaccines based on Virus-like Particles (VLP) produced in cells represent an interesting alternative to the traditional egg-based vaccine. VLPs are non-replicative particles that mimic the virus. Studies on influenza VLPs have shown protection by the intranasal route without adding an adjuvant. During my thesis, a platform for the production of influenza VLPs composed of the hemagglutinin, the neuraminidase and the M1 matrix proteins was developed by transient transfection of mammalian cells. Immunizations of BALB/c mice showed that the purified and characterized type A and B VLPs were immunogenic at low doses by the intramuscular route. The intranasal administration of VLPs with the B subunit of cholera toxin as a mucosal adjuvant resulted in serum antibody levels comparable to those obtained by intramuscular immunization but also a strong IgA response in the mucosal secretions. In addition, VLP yield was found to be strain-dependent and linked to the HA and NA proteins on the surface of the particle. To overcome this problem, a quadrivalent vaccine based on two bivalent VLPs each expressing two different HAs and NAs at the surface was produced, demonstrating the flexibility of this platform

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Delph, Katherine. "Comparison of immunologic responses following intranasal and oral administration of a USDA-approved, live-attenuated Streptococcus equi vaccine." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32595.

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Master of Science
Department of Clinical Science
Elizabeth Davis
Background: While there is a commercially-available vaccine for Streptococcus equi subsp. equi licensed for the intranasal route of administration, some equine practitioners are administering this vaccine orally despite a lack of evidence for its efficacy by this route of administration. Objectives: To compare systemic and local immune responses following intranasal or oral administration of the USDA-approved, live-attenuated Streptococcus equi subspecies equi vaccine (Pinnacle IN®, Zoetis, Florham Park, New Jersey). Study Design: Experimental, randomized clinical trial Methods: Eight healthy horses with low Streptococcus equi M protein (SeM) titers (<1:1600) were randomly assigned to an intranasal or oral two-vaccine series. SeM-specific serum immunoglobulins G (IgG) and A (IgA) and nasal secretion IgA were assessed using a commercially-available ELISA (Equine Diagnostic Solutions, LLC, Lexington, Kentucky) and a novel magnetic microsphere assay utilizing fluorescence. A general linear mixed models approach was used for statistical data analysis. Results: As expected, intranasal vaccinates showed substantial increases in both serum SeM-specific IgG and IgA levels post-vaccination (P=0.0006 and P=0.007, respectively). Oral vaccinates showed an increase in serum SeM-specific IgG post-vaccination (P=0.0150), though only one-third the magnitude of intranasal vaccinates. Oral vaccinates showed no evidence of change in SeM-specific IgA post-vaccination (P=0.15). Main Limitations: Changes in mucosal antibody responses were not identified in this study which may be related to small change in antibody response, timing of sample collection, or method of nasal secretion collection. Conclusions: Results indicate that intranasal or oral vaccine administration resulted in increased serum SeM-specific IgG, though the magnitude of response differed between routes.

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Barri, Adriana. "Effects of Cytosine-phosphate-Guanosine Oligodeoxynucleotides (CpG-ODN) on vaccination and immunization of neonatal chickens." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1550.

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The objective of this investigation was to evaluate the effects of administering CpG-ODN to commercial strain chickens as a potential adjuvant to vaccination against Salmonella, Eimeria spp., and Newcastle disease virus, or immunization to bovine serum albumin (BSA). During Experiment 1, which evaluated the dual application of CpG-ODN and a Newcastle disease virus vaccine, in the first of three replicate trials, on day 28 of the experiment, animals in the Vaccine + CpG 1& 14 experimental group were observed to have the highest levels of (p<0.05) anti-NDV IgG in serum. These levels were elevated above levels in animals from all other experimental groups. This suggestion for an adjuvant effect associated with CpG-ODN administration was not supported in the remaining two trials of experiment 1. Experiment 2 evaluated the potential for CpG-ODN to adjuvant a commercial live oocyst coccidial vaccine when applied by an oral route to neonatal broiler chickens. Overall, when body weight gain during challenge, development of intestinal lesions, and anti-Eimeria IgG levels were evaluated, vaccine administration alone was demonstrated to provide the best measure of protection among animals in all experimental groups, including those receiving either CpG-ODN or Non CpG-ODN. Experiment 3 investigated the simultaneous administration of CpG-ODN or Non-CpG ODN and a commercially acquired Salmonella typhimurium vaccine to SCWL chickens. Similar to experiments 1 and 2, antigen specific IgG responses in serum and indices of protection against field strain Salmonella challenge were variable and inconsistent. Anti-BSA IgG levels were compared in broiler and SCWL chickens immunized against BSA by a drinking water route of administration alone, or in combination with two different concentrations of CpG-ODN or Non CpG-ODN in experiment 4. The only observation where CpG-ODN and BSA co-administration resulted in anti-BSA IgG levels that were elevated above BSA alone immunized chickens was measured in broilers at day 19 post-final immunization. Taken together, given the variable results reported in this investigation related to the co-administration of ODN and vaccine or protein antigen, these data are largely inconclusive for suggesting that CpG-ODN can effectively adjuvant humoral immune responses in commercial strain chickens.

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Rowe, John Christopher. "Targeting Neutrophils to Improve Protection by Sublingual Vaccines." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1612190976457585.

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Lindh, Ingrid. "Plant-produced STI vaccine antigens with special emphasis on HIV-1 p24." Doctoral thesis, Örebro universitet, Akademin för naturvetenskap och teknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-17242.

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Objective: To establish stable transgenic non-toxic plants as a platform for plant-based vaccine production as well as potential oral delivery system of vaccine antigens for sexually transmitted infections (STIs). The concept is to immunize the mucosal immune system present in the gut-associated lymphoid tissues (GALT). HIV-1 p24 subtype C protein has been used as the main antigen model, in parallel with an engineered unique chimeric MOMP antigen from Chlamydia trachomatis serovar E. Methods: Chimeric MOMP and p24 vaccine antigens were successfully inserted into the nuclear genomes of Arabidopsis thaliana and Daucus carota via Agrobacterium-mediated gene transfer. The characteristics of the genetic inserts and corresponding mRNAs and recombinant proteins in planta were described using several methods, including northern, Southern, and western blotting, ELISA, and a commercial HIV Ag/Ab combination assay. Immunogenicity of the antigens was studied in mice models. Results: Transgenes of both plant species expressing p24 or chimeric MOMP were successfully generated. Additional HIV-1 vaccine antigen candidates were introduced and the genetic inserts have been confirmed in Arabidopsis thaliana. The Arabidopsis thaliana expressing p24 and chimeric MOMP were demonstrated to be stable over generations and antigenicity analyses showed that plant-derived HIV-1 p24 and chimeric MOMP retained immunological epitopes when they were expressed in planta. Oral administration of transgenic plant material generated a priming effect of the immune competent cells present in the GALT, shown by the presence of antigen-specific-IgG in mice sera after boosting. Mice immunized with plant-derived HIV-1 p24 antigen were also analyzed for antigen-specific faecal IgA as well as cellular immune responses. However, detectable levels of the two latter immune responses were not observed. The Chlamydia trachomatis chimeric MOMP antigen was further evaluated for its potential as a vaccine antigen candidate, with positive results indicating a more rapid clearance of the Chlamydia trachomatis infection post immunization. Conclusion: Stable non-toxic transgenic plants expressing either HIV-1 p24 or a novel Chlamydia trachomatis chimeric MOMP antigens have successfully been developed. The two plant-produced STI vaccine antigens have in initial mice feeding studies provided important proof-of-concept for the oral vaccination approach. Now, immunization studies to expand, en-hance, and improve knowledge of the immune responses generated by the orally delivered transgenic plants are of high priority.
Kemi/biokemi

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Mulvey, Peter B. "Development of an oral genital herpes vaccine targeting the female reproductive tract with Liporale™, a novel-lipid based adjuvant." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/97998/1/Peter_Mulvey_Thesis.pdf.

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Immunity against genital Herpes Simplex Virus 2 (HSV-2) infection is dependent on local memory immune responses in the genital tract. Oral immunisation can induce mucosal immune responses in the genital tract but has not been tested against viral STIs. Here we describe the mucosal immune responses elicited by an oral vaccine that protects mice against intravaginal challenge from lethal HSV-2 infection. Control of HSV-2 was attributed to HSV-2-specific IgG and IgA in the genital mucosa together with CD4 and CD8 T cells recruited to the genital epithelia. Furthermore, combining this vaccine with vaginal application DNFB to induce transient local inflammation led to the recruitment of CD8 tissue resident memory cells in the genital epithelia that controlled new infection with HSV-2. Thus, this represents the first oral vaccine that can protect mice against lethal intravaginal HSV challenge.

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Ozberk, Victoria. "Design and evaluation of novel liposome-based peptide vaccines for improved efficacy against group A streptococcal infections of the mucosa and skin." Thesis, Griffith University, 2018. http://hdl.handle.net/10072/380063.

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Streptococcus pyogenes (group A streptococcus, GAS) is an important human pathogen that is responsible for a range of diseases. Non-invasive diseases include pharyngitis, scarlet fever and pyoderma/impetigo. GAS is also capable of causing invasive diseases such as streptococcal toxic shock syndrome and necrotizing fasciitis. There is a high chance of mortality associated with GAS invasive diseases, with approximately 8-23% of patients dying within 7 days of infection. Consecutive GAS infections may give rise to auto-immune complications, including acute rheumatic fever (ARF) and rheumatic heart disease (RHD). Approximately 2-3% of patients who acquire streptococcal pharyngitis develop ARF. Skin-associated GAS strains have also been linked to cases of ARF. A vaccine that can stop the progression of disease from the primary sites of infection (URT and skin) is desperately needed.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Institute for Glycomics
Science, Environment, Engineering and Technology
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Philosof, Bar. "A bacterium from the human microbiota as a vaccine vector. Efficient priming of the murine immune system by vaginal delivery of recombinant Streptococcus gordonii." Doctoral thesis, Università di Siena, 2022. http://hdl.handle.net/11365/1216735.

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The ability to prime the immune system against an antigen, and to rapidly recall this response upon antigen reencounter is a fundamental characteristic of the adaptive immune response. The association of an antigen recognized by the immune system in a certain tissue, with the same antigen encountered at a later timepoint in a different tissue, is of primary importance to obtain a systemic and effective immune response and is the foundation behind the utilization of vaccines. The study of vaccine delivery platforms that may activate the immune system in such a manner is therefore of primary importance in the effort to design novel vaccine formulation and prime-boost strategies. The aim of the present work was to study the in vivo priming effect induced by a recombinant Streptococcus gordonii vaccine vector expressing a heterologous antigen and delivered to the vaginal tract, a unique mucosal tissue. To study the priming effect induced by the recombinant Streptococcus gordonii, we employed a prime-boost strategy and compared the cellular an humoral immune response towards the soluble antigen between recombinant- and WT-immunized mice. Using this model, we show that vaginal immunization with the recombinant Streptococcus gordonii elicited systemic production of antigen-specific antibodies, shifted the IgG subclasses profile, led to an increase in plasma cells in the lymph nodes, a higher number of antigen-specific antibody-secreting cells in the spleen and modulated the cytokine expression profile of splenocytes. The longevity of the priming effect induced by the recombinant vector was also analyzed by comparing three and six months boosting schedules. We found that the priming is boostable with a similar efficacy for at least six months (Chapter 3). These data demonstrate that vaginal priming with the recombinant S. gordonii vector results in a systemic activation of both cellular and humoral immune compartments, and that this priming effect is long-lived without significant immune waning. In this study, we also assessed the transcriptomic response of splenocytes from S. gordonii-immunized mice towards the antigen. We observed differences in immune pathways between recombinant- and WT-immunized mice, and also between the three- and six-months boosted groups (Chapter 4). In addition, we observed a gene signature correlated with antigen-specific IgG titers. These findings suggest that the immune system’s encounter with the antigen on the surface of the recombinant S. gordonii in the vaginal tract results in a differential immune activation in in response to the antigen. This work contributes to the knowledge on the capability of recombinant live vaccine vectors delivered mucosally to prime and modulate the immune response, and has important implications in the design of innovative vaccination strategies.

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Hacker, Sibylle Sophie. "Polissacarídeo capsular do Streptococcus agalactiae como antígeno vacinal: desenvolvimento de um modelo vacinal para mucosas com Nanopartícula de quitosana." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/9/9134/tde-28012019-104318/.

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A bactéria gram-positiva Streptococcus agalactiae do grupo B (GBS) faz parte da microbiota normal do trato geniturinário humano, sendo um organismo comensal do corpo da mulher. No entanto, em mulheres grávidas, quando há alterações na composição microbiana do canal vaginal, pode ocorrer a proliferação e a infecção pelo GBS. Este microrganismo, em sua forma patogênica oportunista, pode infectar o neonato durante o parto natural, assim como contribuir para infecções urinárias e uterinas durante a gestação. O GBS já foi identificado como um dos responsáveis pela alta taxa de mortalidade neonatal, sendo um dos principais agentes de infecção em recém-nascidos no mundo. Ele também pode ser a causa de infecções nas gestantes, levando a várias complicações, como corioamnionite, endometrite e infecções do trato urinário e do sítio cirúrgico. Pode haver comprometimento da gestação e do feto, com abortamento, morte fetal intrauterina e ruptura da membrana coriônica, levando a parto prematuro - que pode resultar em outras consequências graves. Este trabalho foi desenvolver um modelo vacinal para mucosa sublingual, utilizando o polissacarídeo capsular do Streptococcus agalactiae como antígeno, encapsulado em Nanopartículas de quitosana. Para o estudo de otimização dos parâmetros de fermentação, para aumentar a produtividade de cápsula polissacarídica (PS) presente na superfície celular, utilizou-se o Banco de Dados Kegg (Kyoto Encyclopedia of Genes and Genomes). A adição do suplemento L-Prolina foi o que propiciou a principio, maior relação entre crescimento bacteriano e formação de cápsula polissacarídica. A purificação e extração da cápsula polissacarídica foi realizada com etapas sucessivas de ultra filtração tangencial e precipitação alcóolica dos contaminantes. As caracterizações físico-químicas: difração de raios-X (DRX), cromatografia gasosa (CGMS), ressonância magnética (NMR) e determinação de açúcares pelo método fenol-sulfúrico, foram realizadas para identificação da composição e estrutura monossacarídica de açucares. O PS isolado apresenta ramificações de fucose, manose, glicose, galactose e N-acetil-glucosamina, apresentando estrutura amorfa. A liofilização do polissacarídeo foi realizada para fins de concentração e conservação. A encapsulação do polissacarídeo acoplada quimicamente com OVA, em uma Nanopartícula de quitosana, teve como finalidade aumentar a mucoadesividade e possibilitar maior absorção do antígeno entre as células da junção epitelial das mucosas sublinguais. A partir da análise de DLS (Espalhamento dinâmico de luz), as Nanopartículas apresentaram dimensões entre 200 a 400 nm e o Potencial Zeta acima de 20. O índice de polidispersão (PDI) está dentro do esperado (abaixo de 0.3). A capacidade de encapsulamento em relação à OVA foi de 92,8% dos grupos que continham PS. O teste IgG sérica total mostrou que o grupo G2 (Nanopartícula com Polissacarídeo e Proteína acoplados) foi o que teve maior reatividade no teste de ELISA, pela Análise de Variância (ANOVA) com ferramenta de Bonferrone. O teste sIgA mostrou que o grupo G2 (Nanopartícula com Polissacarídeo e Proteína acoplados) foi o que teve maior concentração de anticorpo sIgA total. Como resultado e conclusão, o polissacarídeo capsular do Streptococcus agalactiae é um bom candidato a antígeno vacinal.
Gram-positive bacteria Streptococcus agalactiae group B (GBS) is part of the normal microbiota of the human genitourinary tract, being a commensal organism of the female body. However, in pregnant women, when there are changes in the microbial composition of the vaginal canal, GBS proliferation and infection may occur. This microorganism, in its opportunistic pathogenic form, can infect the neonate during natural childbirth, as well as contribute to urinary and uterine infections during pregnancy. The GBS has already been identified as one of the responsible for the high neonatal mortality rate, being one of the main agents of infection in newborns in the world. It can also be the cause of infections in pregnant women, leading to various complications such as chorioamnionitis, endometritis, and urinary tract and surgical site infections. There may be pregnancy and fetal impairment, with abortion, fetal intrauterine death, and rupture of the chorionic membrane, leading to premature labor - which can result in other serious consequences. This work was to develop a vaccine model for sublingual mucosa using the capsular polysaccharide of Streptococcus agalactiae as antigen, encapsulated in chitosan nano particles. For the study of optimization of the fermentation parameters, the Kegg (Kyoto Encyclopedia of Genes and Genomes) database was used to increase the productivity of polysaccharide capsule (PS) present on the cell surface. The addition of the L-Proline supplement gave rise to a higher ratio between bacterial growth and polysaccharide capsule formation. The purification and extraction of the polysaccharide capsule was performed with successive stages of tangential ultrafiltration and alcoholic precipitation of the contaminants. The physicochemical characterization of X-ray diffraction (XRD), gas chromatography (CGMS), magnetic resonance (NMR) and determination of sugars by the phenol-sulfuric method were performed to identify the composition and monosaccharide structure of sugars. The isolated PS presents branches of fucose, mannose, glucose, galactose and N-acetyl-glucosamine, presenting amorphous structure. Lyophilization of the polysaccharide was performed for concentration and conservation purposes. The encapsulation of the polysaccharide coupled chemically with OVA in a chitosan nano particle was aimed at increasing mucoadhesiveness and allowing greater absorption of the antigen between the cells of the sublingual mucosal epithelial junction. From the analysis of DLS (dynamic light scattering), the nanoparticles presented dimensions between 200 to 400 nm and the Zeta potential above 20. The polydispersity index (PDI) is within the expected range (below 0.3). The encapsulation capacity for OVA was 92.8% of the groups containing PS. The total serum IgG test showed that the G2 group (Nano particle with Polysaccharide and Protein coupled) was the one that had the highest reactivity in the ELISA test, by Analysis of Variance (ANOVA) with Bonferrone tool. The sIgA test showed that the G2 group (Nanoparticle with Polysaccharide and Protein coupled) had the highest concentration of total sIgA antibody. As a result and conclusion, the capsular polysaccharide of Streptococcus agalactiae is a good candidate for vaccine antigen.

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SIEDLER, Bianca Sica. "Avaliação de uma vacina de aplicação intravaginal contra o Herpesvírus bovino tipo 5 (BoHV-5) associada a subunidade B recombinante da enterotoxina termolábil de Escherichia coli (rLTB)." Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/2466.

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Mucosal immune system represents the initial barrier against many pathogens, including bovine herpesviruses (BoHV). After infection of mucous membranes, mainly nasal and genital, these viruses disseminate locally followed by viremia and neural spread. Innate defense mechanisms along with adaptive immunity confer protection to mucosal surfaces. In this context, secretory IgA (sIgA) plays an essential role in the mucosal humoral immunity, conferring protection to these body surfaces through different mechanisms, including viral neutralization. This class of antibody predominates in the vaginal mucosa of cattle playing an important role in the local defense against infections. Considering the importance of this infection route in herpesviruses pathogenesis, there is a growing interest in the development of vaccines that provide mucosal immunity against these viruses. In the present study, eight cows were divided in two groups (G1 and G2) and inoculated intravaginally with inactivated BoHV-5 associated with recombinant Escherichia coli heat-labile enterotoxin B subunit (rLTB) and xanthan (G1) and inactivated BoHV-5 associated with xanthan (G2). Local and systemic humoral immune response (IgA and IgG) induced after inoculation was measured by indirect ELISA. An increment in the levels of IgA and IgG was detected in sera, nasal and genital mucosa of all the immunized animals. Furthermore, the relative expression of interleukins 2 and 13 (IL-2 and IL-13) was investigated by real-time PCR indicating an increased mRNA expression of these cytokines in leukocytes collected from animals immunized with the experimental vaccine. These results demonstrate that the experimental intravaginal BoHV-5 vaccine induced a local and systemic immune response in cattle. The results also corroborated the immunostimulant activity of the rLTB in mucosal membranes and confirmed the use of xanthan as a delivery system for intravaginal vaccines. Our data also reinforce the importance of this route for administration of vaccines focused on providing local protection against pathogens.
O sistema imune de mucosa representa a barreira inicial frente a diversos patógenos que utilizam estas superfícies como porta de entrada no organismo, como é o caso dos herpesvírus bovinos (BoHV). Estes vírus utilizam as mucosas, principalmente nasal e genital, como ponto inicial de replicação, seguida de disseminação local, viremia sistêmica e disseminação neuronal. Mecanismos inatos de defesa em cooperação direta com mecanismos adaptativos conferem proteção a estas mucosas. A IgA secretora (sIgA) representa um papel fundamental na imunidade humoral destes locais, conferindo proteção a estas superfícies através de distintos mecanismos, incluindo a neutralização viral. Este anticorpo predomina na mucosa vaginal de bovinos, sendo essencial na defesa local frente a patógenos de transmissão genital. Devido a grande importância das vias mucosas na transmissão dos BoHV, torna-se evidenciado o interesse no desenvolvimento de vacinas que propiciem imunidade de mucosa contra estes agentes etiológicos. No presente estudo, oito fêmeas bovinas foram divididas em dois grupos (G1 e G2) e inoculadas por via intravaginal com BoHV-5 inativado associado à subunidade B recombinante da enterotoxina termolábil de Escherichia coli (rLTB) e xantana (G1) e BoHV-5 inativado associado a xantana (G2). A resposta humoral (IgA e IgG) local e sistêmica induzida nos animais inoculados foi mensurada através do teste de ELISA indireto. A vacina avaliada demonstrou-se capaz de incrementar os níveis de IgA e IgG no soro e nas mucosas nasal e vaginal dos bovinos imunizados. A expressão relativa das interleucinas 2 e 13 (IL-2 e IL-13) foi avaliada através da técnica de real time RT-PCR, a partir dos leucócitos dos animais vacinados, resultando em aumento na expressão de mRNA destas citocinas nos animais inoculados com a vacina experimental. Estes dados comprovam a capacidade da vacina de aplicação intravaginal em bovinos de estimular uma resposta imune local e sistêmica, além de corroborar a atividade imunoestimulante em mucosas da rLTB e também validar a utilização da xantana como sistema de entrega de vacinas de aplicação intravaginal. Portanto, esta via de administração de vacinas torna-se uma alternativa interessante, principalmente quando se objetiva gerar proteção local contra patógenos que utilizam as superfícies mucosas como porta de entrada no organismo.

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Kalfayan, Lina H. "Mucosal immunizations in a humanized transgenic mouse model and development of novel multimeric tools for detection of cellular immunity towards an HIV vaccine." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103163.

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Viral vector-based vaccines represent an effective means of in vivo antigen expression and the ensuing generation of a sustained immune response in the host. These new generation vaccines are deemed promising against pathogens for which researchers have so far failed to put forth preventive strategies and/or effective, accessible, treatment modalities. HIV-1 stands at the foremost of this list. In the current study, we have evaluated the use of two different viral vector-based vaccines against Clade A of HIV-1, namely recombinant modified vesicular stomatitis virus (VSV-AV3) and Adenovirus serotype 5 (Ad5) expressing the Gag protein from subtype A. These viral vectors, which are also inherently endowed with adjuvant properties, were delivered via a mucosal immunization strategy in a humanized transgenic mouse model. Transgenic mice expressing both HLA-A*0201 and HLA-DR*0101 represent a versatile model in which HIV-specific immunogenic epitopes and the resulting T cell receptor (TCR) specificity can be determined. We show that following mucosal delivery of vaccine, there is induction of antigen-specific systemic T cells against epitopes which were previously shown to be immunogenic in humans. We next developed novel multimeric reagents for the detection of CD4 + T cells, namely dodecameric HLA-DR1 molecules using a murine immunoglobulin M (IgM) scaffold. These reagents aim at increasing the overall avidity of peptide-MHC Class II complexes to detect low-affinity TCRs. These multimers were able to activate in vitro a Jurkat T cell line in an antigen-specific manner. The identification and characterization of the molecular requirements boosting the qualitative and quantitative features of the immune response to HIV vaccines, in addition to the development of novel state-of-the-art immune monitoring tools, will be crucial in better understanding of the mechanisms of interaction between the virus and the host immune system, leading to rational strategies in the fight against the AIDS epidemic.

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Cheramie, Martin N. "Investigations into Mycobacterium marinum Interacting and Crossing Fish Gut Epithelia| Evidence for Inducing a Protective Gut Mucosal Immunity by a Live Vaccine Candidate." Thesis, University of Louisiana at Lafayette, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1585851.

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Mycobacterium marinum is an established surrogate pathogen for Mycobacterium tuberculosis because of M. marinum 's strong conservation of thousands of orthologous genes, lower risk, lower financial burden to researchers, and similar pathology in fish. This pathogen causes TB-like chronic disease in a wide variety of fish species and can mount superficial infection of human tissues. As in human TB, the microbe grows within the host macrophages, can mount life-long chronic infections, and produces granulomatous lesions in target organs. One of the fish species known to manifest chronic "fish TB" is the small laboratory fish, Japanese medaka (Oryzias latipes). Recently, our lab documented the progression of the bacterium from the lumen of the gut to underlying tissues and to target organs to mount infection. Since the bacterium can be observed crossing the epithelia to mount infection, I tested to see if mucosal immunity against a wild-type challenge could be induced by initially priming the fish to a live, attenuated vaccine strain. This thesis demonstrates that inoculation by ingestion is an efficient mode by which medaka can become infected and vaccinated with M. marinum. Furthermore, my thesis shows that orally vaccinating fish with a live, attenuated strain indeed provides protection in the gut, liver, and kidney against a virulent, wild-type challenge.

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Dhakal, Santosh. "Development and Evaluation of Nanoparticle-based Intranasal Inactivated Influenza Virus Vaccine Candidates in Pigs." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1529829066502348.

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Paccez, Juliano Domiraci. "Aplicação de linhagens geneticamente modificadas de Bacillus subtilis no desenvolvimento de vacinas de mucosas contra patógenos entéricos." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/42/42132/tde-31012008-093802/.

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Bacillus subtilis é uma bactéria gram positiva de solo, não patogênica, não colonizadora de tecidos, naturalmente transformável e formadora de esporos utilizada como modelo de estudo de bactérias gram-positivas. Essas características acarretam em vantagens para a produção de proteases de interesse industrial e para utilização como veículo de antígenos vacinais, porém a falta de vetores induzíveis torna sua utilização como ferramenta biológica pouco explorada. No presente trabalho descrevemos a construção de diferentes vetores capazes de expressar os antígenos subunidade B da toxina termo-lábil (LTB) e subunidade estrutural da fímbria CFA/I (CFAB) de Escherichia coli enterotoxigênica (ETEC) e avaliamos seu potencial vacinal. Foi avaliada a imunogenicidade de linhagens capazes de expressar LTB sob o controle de diferentes promotores: PgsiB (induzido em condições de estresse), PlepA (promotor constitutivo) e Pspac (induzido pela adição de IPTG) e em diferentes locais da célula (ancorada à parede celular ou secretada para o meio externo). Avaliamos ainda a imunogenicidade de linhagens capazes de co-expressar LTB e a listeriolisina O (LLO) de Listeria monocytogenes. O antígeno CFAB foi produzido no citoplasma ou ancorado à parede celular de B. subtilis em condições de estresse e as linhagens bacterianas administradas sozinhas ou conjuntamente com a toxina termo-lábil (LT) como adjuvante de mucosa. Camundongos imunizados com células ou esporos de B. subtilis recombinantes desencadearam respostas de anticorpos sistêmicos e secretados específicos para os antígenos (LTB e CFAB), não alterados pela adição do adjuvante. A expressão de LLO causou a supressão da resposta de anticorpos específicos para o antígeno LTB. Os resultados obtidos demonstram a viabilidade do uso de B. subtilis como veículo vacinal.
Bacillus subtilis is a gram positive, generally regarded as safe and spore forming soil bacteria used as a model for genetic and phisiological studies. This safety status allow its use as host for production of industrial protases and its application as vaccine vehicles, however the lack of epissomal inducible expression systems disable the exploration of this organism as a biotechnologic tool. In this work we describe the construction of epissomal vectors able to express the B subunit of the heat-labile toxin (LTB) and the structural subunit of the CFA/I fimbrae (CFAB) from the enterotoxigenic Escherichia coli (ETEC). We evaluate strains able to express LTB under the control of three promoters: PgsiB (stress inducible), PlepA (constitutive) e Pspac (IPTG inducible) and allowing the expression of LTB secreted or anchored to the cell wall We also evaluate the immunogenicity of strains able to co-express LTB and the listeriolysin O (LLO) from Listeria monocytogenes. CFAB was expressed in the cytoplasm or anchored to the cell wall and administred alone or with the mucosal adjuvant LT. Mice immunized both with cells or spores elicited secreted and systemic specific antibodies responses, which were not altered by the addition of the adjuvant LT. LLO expression suppressed the antibodies responses against LTB. The data shows the ability of B. subtilis to be used as vaccine vehicle.

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Rydell, Niclas. "Development of a New Oral Vaccine against Diphtheria and the Study of its Immunogenicity in Mouse and Man." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4629.

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Stertman, Linda. "Starch Microparticles as an Oral Vaccine Adjuvant with Emphasis on the Differentiation of the Immune Response." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ-.bibl. [distributör], 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4680.

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Okino, Cintia Hiromi [UNESP]. "Imunidade celular e humoral o trato respiratório de galinhas desafiadas com o vírus da bronquite infecciosa e efeito de subdosagens da vacina na indução da proteção." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/104624.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
As respostas imunes inatas e adquiridas, incluindo-se aí tanto as mediadas por fatores humorais como celulares normalmente induzidas após a infecção ou vacinação com o vírus da BI (VBI), são caracterizadas por sua grande complexidade e por aspectos relevantes que ainda são pouco conhecidos, no que tange aos elementos capazes de exercer uma ou mais ações efetoras contra esse patógeno e que culminassem na restrição da replicação viral, seguido de sua eliminação do organismo hospedeiro e também no impedimento de lesões mais severas. Isso posto, foi formulado o presente estudo com o fito principal de fazer a avaliação das respostas imunes humorais e celulares em diferentes intervalos pós-desafio com o VBI de aves previamente vacinadas ou não, realizando-se a mensuração de anticorpos no soro e na lágrima, e a quantificação da expressão de genes relacionados às respostas imunes na superfície traqueal, a fim de correlacionar tais parâmetros com o estado de proteção ao desafio. Os resultados demonstraram que os aumentos significativos nos níveis de anticorpos lacrimais dos isótipos IgG e IgA nas aves previamente vacinadas e também na expressão dos genes relacionados às respostas imunes, sobretudo o CD8, a Granzima A e o IFNg foram correlacionados negativamente com um ou mais parâmetros de alterações patológicas traqueais. Constatou-se também, que a memória das respostas imunes humorais e cito-mediadas conferida por uma única vacinação contra a BI no primeiro dia de idade é dependente da dose vacinal administrada
Avian infectious bronchitis virus (IB) is a worldwide infectious disease which causes significant economic losses in poultry industry. The innate and acquired immune responses, including whether there mediated by both cellular and humoral factors that are induced after infection or vaccination with IB virus (IBV) are characterized by their higher complexity and for the relevant aspects that are still poorly known, with respect to the elements able to exercise one or more actions against the pathogen and that culminate in the restriction of its propagation and also on your clearance of the host organism. So, this project was formulated with the main done to make the evaluation of cellular and humoral immune responses at different intervals post-immunization or postchallenge with IBV poultry previously vaccinated or not, performing the measurement of antibodies in serum or tears and quantitation of the expression of genes related to immune responses in tracheal surface, correlating these parameters with the protection against IBV. The results showed that both significative increase of IgG and IgA isotypes in tears of previously vaccinated chickens and the expression levels of genes related to immune responses, especially CD8, Granzyme A and IFN g were negatively correlated with one or more parameters of pathological lesions at trachea. Moreover, we found that the immune memory conferred by vaccination against BI on the first day of age is dependent on vaccine dose administered

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Massis, Liliana Moura. "Imunogenicidade e potencial vacinal das flagelinas de Salmonella enterica sorovar Typhimurium." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/42/42132/tde-28012008-142626/.

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Flagelina, a subunidade estrutural dos flagelos bacterianos, pode ser empregada em estratégias vacinais como carregadora de epitopos antigênicos fusionados ou como adjuvante. Neste trabalho avaliamos a imunogenicidade e o potencial vacinal das flagelinas Salmonella enterica sorovar Typhimurium em camundongos BALB/c após administração pelas vias oral ou intraperitoneal. Os resultados indicam que animais imunizados pela via oral com linhagens flageladas de S. Typhimurium não desenvolvem respostas de anticorpos, sistêmicos ou secretados, anti-flagelina, por outro lado, ativam respostas celulares específicas para as flagelinas em função da via de administração utilizada. Observamos ainda que as diferentes flagelinas testadas apresentam efeito adjuvante quando co-administradas pela via nasal com a fímbria CFA/I de ETEC. Em suma, os resultados apresentados contribuem para um melhor conhecimento sobre as propriedades imunológicas e adjuvantes das flagelinas de S. Typhimurium e agregam informações para o uso racional dessas proteínas em formulações vacinais.
Flagellin, the structural subunit of bacterial flagella, can be used in vaccine development as a fused antigenic epitope carrier or as an adjuvant. In this work we evaluated the immunogenicity and vaccine approach of S. Typhimurium flagellin in BALB/c mice after administration by oral or intraperitoneal route. Our results indicate that mice immunized by oral route with flagellated S. Typhimurium strains do not develop any anti-flagellin antibody response, be it serum or secreted. On the other hand, specific anti-flagellin cellular response was observed depending on the chosen route of immunization with S. Typhimurium attenuated strain. Furthermore, all flagellins tested proved to be efficient adjuvants when co-administrated with CFA/I fimbriae by nasal route. Together, these results contribute to a better understanding of the immunological and adjuvant properties of S. Typhimurium flagellins and also provide information on the rational use of these proteins in vaccine development.

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Permpoonpattana, Patima. "Clostridium difficile : infection and immunity." Thesis, Royal Holloway, University of London, 2013. http://repository.royalholloway.ac.uk/items/33009ec4-7815-0803-d39b-f968c8d9cdbb/7/.

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Clostridium difficile is a Gram positive pathogen of significant importance in the UK, Europe and the USA. No vaccine has been developed and current treatments are focused on hospital management and the use of antibiotics. The disease is spread in hospitals in the spore form and the role of spores in C. difficile infecton is poorly understood. In this project spores of C. difficile have been characterised. The proteins from the outermost layers of the spore were identified and the genes cloned. Three of these surface proteins have unique enzymatic properties that maybe important for symptoms of disease. The ability of C. difficile spores to adhere to intestinal cells was found to be far greater than with live cells and through this we have identified that the spore may play an important role in colonisation. The regulation of spore coat gene expression during sporulation was also examined and temporal phases of genes expression identified. A major part of this project was to develop a mucosal vaccine to C. difficile. The approach used was to clone the C-terminus of toxin A onto the surface of Bacillus subtilis spores and use these recombinant spores to immunise mice and hamsters. We found that oral delivery of these spores conferred 75% protection to C. difficile infection in a hamster model of infection. Further, parenteral immunisation of the same antigens (toxin A and B) failed to generate mucosal responses and this showed that mucosal immunisation is critical for good protection. Finally, we found that antibodies to the C-terminus of toxin A were cross reactive to the C-terminus of toxin B. This showed that mucosal delivery of just the C-terminus of toxin A is sufficient to confer protection in an animal model of infection. The outcome of this work is that we have shown the parameters for successful immunisation and vaccination against C. difficile.

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Okino, Cintia Hiromi. "Imunidade celular e humoral o trato respiratório de galinhas desafiadas com o vírus da bronquite infecciosa e efeito de subdosagens da vacina na indução da proteção /." Jaboticabal : [s.n.], 2010. http://hdl.handle.net/11449/104624.

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Orientador: Hélio José Montassier
Banca: Adolorata Aparecida Bianco Carvalho
Banca: Clarice Weins Arns
Banca: Geraldo Aleixo da Silva Passos Júnior
Banca: Liana Brentano
Resumo: As respostas imunes inatas e adquiridas, incluindo-se aí tanto as mediadas por fatores humorais como celulares normalmente induzidas após a infecção ou vacinação com o vírus da BI (VBI), são caracterizadas por sua grande complexidade e por aspectos relevantes que ainda são pouco conhecidos, no que tange aos elementos capazes de exercer uma ou mais ações efetoras contra esse patógeno e que culminassem na restrição da replicação viral, seguido de sua eliminação do organismo hospedeiro e também no impedimento de lesões mais severas. Isso posto, foi formulado o presente estudo com o fito principal de fazer a avaliação das respostas imunes humorais e celulares em diferentes intervalos pós-desafio com o VBI de aves previamente vacinadas ou não, realizando-se a mensuração de anticorpos no soro e na lágrima, e a quantificação da expressão de genes relacionados às respostas imunes na superfície traqueal, a fim de correlacionar tais parâmetros com o estado de proteção ao desafio. Os resultados demonstraram que os aumentos significativos nos níveis de anticorpos lacrimais dos isótipos IgG e IgA nas aves previamente vacinadas e também na expressão dos genes relacionados às respostas imunes, sobretudo o CD8, a Granzima A e o IFNg foram correlacionados negativamente com um ou mais parâmetros de alterações patológicas traqueais. Constatou-se também, que a memória das respostas imunes humorais e cito-mediadas conferida por uma única vacinação contra a BI no primeiro dia de idade é dependente da dose vacinal administrada
Abstract: Avian infectious bronchitis virus (IB) is a worldwide infectious disease which causes significant economic losses in poultry industry. The innate and acquired immune responses, including whether there mediated by both cellular and humoral factors that are induced after infection or vaccination with IB virus (IBV) are characterized by their higher complexity and for the relevant aspects that are still poorly known, with respect to the elements able to exercise one or more actions against the pathogen and that culminate in the restriction of its propagation and also on your clearance of the host organism. So, this project was formulated with the main done to make the evaluation of cellular and humoral immune responses at different intervals post-immunization or postchallenge with IBV poultry previously vaccinated or not, performing the measurement of antibodies in serum or tears and quantitation of the expression of genes related to immune responses in tracheal surface, correlating these parameters with the protection against IBV. The results showed that both significative increase of IgG and IgA isotypes in tears of previously vaccinated chickens and the expression levels of genes related to immune responses, especially CD8, Granzyme A and IFN g were negatively correlated with one or more parameters of pathological lesions at trachea. Moreover, we found that the immune memory conferred by vaccination against BI on the first day of age is dependent on vaccine dose administered
Doutor

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Hathaway, Lucy Jane. "Mucosal immunization with synthetic peptides for the systemic and mucosal immune responses." Thesis, London School of Hygiene and Tropical Medicine (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267621.

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Bernocchi, Beatrice. "Porous maltodextrin nanoparticles for the intranasal delivery of vaccines." Thesis, Lille 2, 2016. http://www.theses.fr/2016LIL2S010/document.

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Au cours des dernières décennies, la technologie des nanoparticules pour la délivrance des vaccins au niveau de muqueuses a reçu un intérêt croissant. L’administration intranasale possède de grands avantages pour la stimulation du système immunitaire, telles que la stimulation d’une immunité protectrice locale et systémique. Cependant des systèmes de délivrance et des adjuvants sont souvent nécessaires pour déclencher efficacement la réponse immunitaire. Nous avons appliqué la technologie des nanoparticules en tant que système de délivrance d'un vaccin universel nasal contre la grippe dans un projet européen FP7 appelé UniVacFlu. Nous avons formulé un antigène adjuvé CTA1-3M2e-DD avec les NPL. Cet antigène est composé de la sous-unité A1 de la toxine du choléra et d’un épitope conservé du virus de la grippe A (M2e), ainsi que du dimère de l’analogue synthétique de la protéine A de Staphylococcus aureus (DD). Les nanoparticules utilisées sont poreuses et constituées de maltodextrines réticulées ayant un coeur lipidique (NPL). L’association de cet antigène avec les NPL est quantitative et la formulation est stable pendant au moins six mois à 4°C. Les NPL permettent également de délivrer d’une manière accrue cet antigène dans les cellules épithéliales des voies respiratoires et les macrophages. Actuellement ces formulations sont évaluées chez la souris par le consortium UniVacFlu.L'un des principaux problèmes des vaccins nasal est la toxicité qui peut être provoquée par le passage nez-cerveau de l'un de ses composants. Le but de ce travail est d'évaluer le potentiel des NPL, en tant que vecteurs pour la délivrance des vaccins nasal. Ainsi, nous avons étudié le chargement d’un antigène dans les NPL et sa délivrance dans les cellules épithéliales des voies respiratoires. Notre étude révèle que les NPL interagissent fortement avec les muqueuses et délivrent d’une manière accrue les antigènes dans les cellules. Nous avons également montré l'absence de transcytose et de passage paracellulaire des NPL ou des antigènes délivrés dans un modèle de barrière épithéliale in vitro. Les résultats in vivo confirment l'absence de passage nez-cerveau des NPL et montrent qu’elles prolongent fortement le temps de résidence nasale des antigènes qui sont ensuite éliminés par le tractus gastro-intestinal.Ces résultats mettent en évidence l'intérêt des NPL comme vecteurs pour la prochaine génération de médicaments et de vaccins
Nanoparticles technology for mucosal delivery of vaccines received a growing interest in the last decades. Intranasal administration owns great advantages for immune system stimulation, such as local and systemic protection against infectious diseases. However delivery systems and adjuvants are often required to efficiently trigger mucosal and systemic immune responses. In this thesis, nanoparticles (NP) have been evaluated as delivery system for a nasal universal influenza vaccine in a People Program of the European Union Seventh Framework Program FP7 called UniVacFlu. The aim of the UniVacFlu network is to develop a universal influenza vaccine administered through the mucosal route. We used porous maltodextrin nanoparticles with a lipidic core (NPL). We loaded an adjuvanted antigen named CTA1-3M2e-DD in the NPL. CTA1-3M2e-DD is composed of the A1 subunit of the cholera toxin and a conserved epitope of influenza A virus (M2e), while DD, dimer of the synthetic analogue of the Staphyloccous aureus protein A, targets B cells. Interestingly the antigen loading in NPL was quantitative for the antigen: NPL 1:5 mass ratio and the formulation was stable for at least six months at 4°C. We assessed the successful delivery of the antigen by NPL in airway epithelial cells and macrophages. These formulations are currently evaluated by the UniVacFlu consortium in mice.One of the main issues of intranasal vaccines is the toxicity that can be elicited by the nose-brain passage of one of their components. We investigated the loading of antigens in NPL and their delivery in airway mucosa. We observed a high endocytosis of NPL and an increased protein delivery into the cells. On a transwell model of the airway mucosa we assessed the absence of transcytosis and paracellular passage of the NPL. In vivo results confirmed the lack of nose-brain passage of the NPL, as NPL were found not to cross the mucosa. Interestingly, we observed an increased nasal residence time of the protein targeted by NPL. The particles after having delivered their payload are totally eliminated through the gastrointestinal tract, making these nanoparticles good candidates for mucosal delivery system. These results highlight the interest of NPL as vectors for mucosal delivery of drugs

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Gutjahr, Alice. "Évaluation de combinaisons de ligands de PRR et de particules biodégradables pour la vaccination muqueuse." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1325.

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De nombreux obstacles freinent le développement d'un vaccin efficace contre le VIH. Pour franchir ces barrières, le recours aux adjuvants est une option prometteuse. Dans ce contexte, l'objectif de ce doctorat est l'évaluation de combinaisons de ligands de PRR et de particules biodégradables pour la vaccination muqueuse. La première partie de l'étude vise à analyser la valeur ajoutée de molécules hybrides composée de deux ligands de PRR comparée à la co-administration des deux agonistes. Des molécules stimulant TLR7 et TLR2 puis TLR7 et NOD2 ont été évaluées. Nous avons démontré l'intérêt de l'association de ligands de PRR au sein d'une même molécule, pour l'induction de réponses immunitaires systémiques et muqueuses. Des études récentes ont montré l'intérêt d'agonistes de STING comme adjuvant vaccinaux. Nous avons étudié l'induction de réponses immunitaires par les agonistes de STING, administrés par voie parentérale ou muqueuse. Nous avons démontré le fort potentiel de ligands de STING pour l'induction de réponses cellulaires et muqueuses. Lors de ces études, nous avons démontré que l'intérêt de la vectorisation d'agonistes de PRR dépend de la molécule. En effet, bien que la vectorisation d'une molécule hybride TLR7/TLR2 n'ait pas d'impact sur la réponse immunitaire induite, la vectorisation d'agonistes de STING potentialise leur effet immunostimulant. Pour finir, nous avons montré que la voie d'administration a un impact sur la réponse immunitaire induite. Afin de mieux comprendre les mécanismes mis en jeu, une étude de biodistribution des formulations de NP de PLA après administration par voie systémique ou muqueuse a été réalisée
There are many barriers to the development an effective HIV vaccine. The use of adjuvants is a promising option to overcome these obstacles. In this context, the objective of this PhD is the evaluation of combinations of PRR ligands and biodegradable particles for mucosal vaccination.The first part of this study aimed at assessing the added value of hybrid molecules composed of two PRR ligands compared to the co-administration of the two agonists. TLR7 and TLR2 stimulating molecules followed by TLR7 and NOD2 were evaluated. We demonstrated the interest of the association of PRR ligands within the same molecule for the induction of systemic and mucosal immune responses.Recent studies showed the interest of STING agonists as a vaccine adjuvant. We investigated the induction of immune responses by STING agonists administered parenterally or mucosally. We confirmed the strong potential of STING ligands for the induction of cellular and mucosal responses.In these studies, we demonstrated that the interest of vectorization of PRR agonists depends on the molecule. Indeed, although the encapsulation of a TLR7/TLR2 hybrid molecule has no impact on the induced immune response, the vectorization of STING agonists potentiates their immunostimulatory effect.Finally, we showed that the route of administration has an impact on the immune response induced. In order to better understand the mechanisms involved, a biodistribution study of PLA NP formulations after systemic or mucosal administration was performed

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Nguyen, Uyen Quynh. "The use of bacterial spores as mucosal vaccines." Thesis, Royal Holloway, University of London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437234.

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Allsop, Julie Kay. "Development of nucleic acid vaccines for mucosal delivery." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263104.

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Tregoning, John Simmons. "An investigation of mucosal vaccines expressed in tobacco chloroplasts." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404591.

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Pattani, Aditya Sunil. "Formulation strategies for the mucosal delivery of HIV vaccines." Thesis, Queen's University Belfast, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.557642.

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Vaccination seems to be the key to curtailing the HIV epidemic but all efforts to make a clinically effective vaccine have failed to date. Eliciting high titres of neutralising antibodies at the mucosal portals of viral entry is a key goal in HIV vaccine research. Thus, this thesis specifically focuses at the strategic development and evaluation of women-controlled mucosal vaccine delivery systems for HIV envelope based constructs, H4A, gp140 and FP-A for the purpose of eliciting high antibody titres at the vaginal mucosa. Sustained release rod-insert vaginal rings (RiRs) loaded with gp140, quick release rods containing H4A, FP-A loaded liposomal gels and microneedles in conjunction with mucosal inoculations were evaluated for induction of specific antibodies in animal models (sheep/mice/rabbits). The formulations were evaluated mainly using vaginal delivery with nasal route being used as an auxiliary. However, we found that the nasal route was extremely potent compared to the vaginal route for the induction of antibody responses. In addition, we found that there is a definite rationale for sustained vaginal delivery ofvaccines. FP-A loaded gels showed ability to elicit neutralising antibody at mucosal sites and are hence being scaled to GMP production with a view to progressing them to clinical trials. Storage stability of bovine serum albumin (BSA) loaded RiRs and protein loaded immediate release dosage forms were also evaluated. Protein aggregation was found to be the most important route of degradation of BSA in RiRs, while freeze-drying induced changes predominate in the immediate release dosage forms. Finally, a solvent emulsion diffusion based method was developed for the generation of neutral, anionic and cationic liposomes. Homogenisation time was studied as a process parameter; however this was not able to control the particle size significantly.

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Fasquelle, François. "Etude de la délivrance d’antigènes dans les voies aériennes en utilisant des nanoparticules de maltodextrine lipidées." Thesis, Lille, 2020. https://pepite-depot.univ-lille.fr/LIBRE/EDBSL/2020/2020LILUS024.pdf.

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L’administration de vaccins par voie muqueuse (orale et nasale) est une alternative efficace aux injections classiques. En effet, au-delà d’une plus grande compliance pour les patients et les soignants, ces voies ont l’avantage de déclencher une immunité dite muqueuse, grâce à la présence d’un système immunitaire propre (aussi appelé MALT pour Mucosal Associated Lymphoid Tissue). Ce MALT est situé à la surface des épithélia de revêtement. Il est différencié en îlots distinguables, les Follicular Associated Epithelium (FAE), et est constitué de cellules épithéliales spécialisées dans la surveillance et le prélèvement de pathogènes, les cellules M. Celles-ci surplombent une zone riche en cellules présentatrices d’antigènes (CPA) et lymphocytes, les Interfollicular Regions (IFR). Ainsi lors d’une infection, les cellules M sont capables de prélever et transloquer des fragments antigéniques vers les CPA, qui initieront la réponse immunitaire auprès des lymphocytes. Cette réponse se traduira par une immunité humorale et cellulaire au niveau de l’épithélium infecté, au niveau des muqueuses plus distantes, mais aussi au niveau systémique. Comme la majorité des infections se produisent au niveau des muqueuses, cette stratégie d’immunisation est de plus en plus étudiée.Si les antigènes sous-unitaires sont moins toxiques que les vaccins vivants, ils sont aussi moins immunogènes, et leur administration nécessite la présence d’un adjuvant pour stimuler efficacement les CPA et initier une réponse immunitaire forte. Or, par la voie des muqueuses, les molécules immunomostimulantes classiquement utilisées pour les voies injectables (par exemple les toxines bactériennes, le LPS ou encore certaines émulsions) sont souvent reportées comme étant toxiques. L’utilisation de systèmes de délivrance pour vectoriser les antigènes jusque dans les CPA semble donc être une alternative séduisante.On distingue deux types de vecteurs d’antigènes : les particules immunomodulatrices, et les systèmes de délivrance purs. Les premiers délivrent les antigènes dans les CPA, et en parallèle, stimulent fortement les voies pro-inflammatoires, pour orienter la balance immunitaire Th1/Th2. Parmi ces vecteurs, les plus utilisés en tests cliniques sont les virus-like particles (VLP), les émulsions à base de saponines (ISCOMs) ou les liposomes contenant des éléments bactériens (MPL, CpG…). En revanche, leur utilisation par voie muqueuse, et notamment nasale, est confrontée aux mêmes risques de toxicité que les adjuvants classiques. Les systèmes de délivrance purs, quant à eux, n’améliorent l’immunogénicité des antigènes qu’en les délivrant dans les cellules, mimant ainsi une infection naturelle. Et bien qu’ils soient mieux tolérés par les muqueuses, leur efficacité doit s’orienter vers une pénétration du mucus, ainsi qu’une association, protection et délivrance des antigènes dans les CPA bien plus performantes.Durant cette thèse, nous avons ainsi étudié les mécanismes permettant à des nanoparticules (NPs) de maltodextrine cationiques et lipidées (NPL) de délivrer des antigènes par voie nasale.Nous avons tout d’abord évalué la capacité des NPL à franchir le mucus des voies respiratoires, en comparaison avec des nanoparticules mucopénétrantes (des PLGA recouvertes de PEG, ou PLGA-PEG) et des nanoparticules mucoadhérentes (des PLGA recouvertes de chitosan, ou PLGA-CS). En mesurant le déplacement des différentes NPs dans du mucus respiratoire reconstitué, nous avons observé que, grâce à la présence du coeur de phospholipides anioniques, la NPL était capable de se déplacer dans le mucus, contrairement aux PLGA-CS qui restaient immobiles [...]
The mucosal routes of immunization present several advantages compared to classical injection routes. Indeed, besides a better compliance towards patients, these routes possess their own immune system, also known as the Mucosal Associated Lymphoid Tissue (MALT), able to trigger a local mucosal response after immunization. This tissue is mainly located in the nasal and intestinal mucosa, where it is spread in small extents called Follicular Associated Epithelium (FAE). On their apical surface, the FAE contain specialized epithelial microfold cells (or M cells), whose role is to survey potential infections by sampling pathogenic fragments, and which overlay a lymphocyte and antigen presenting cells (APC) zone. Then, when an infection occurs, M cells sample and translocate antigenic fragments to CPA, which could therefore trigger lymphocyte maturation and the initiation of the subsequent immune response. This activation will lead to both humoral and cellular immunity in the infected epithelium and could also spread to distant mucosa. As many pathogens infect the body through mucosa, this way of immunization is often considered.Adjuvants are frequently added to subunit vaccines to enhance their immunogenicity toward APC. Indeed, despite their lower toxicity, they are also less immunogenic than live-attenuated vaccines. However, the administration of classical adjuvanting molecules, such as toxins or immunostimulating emulsions, via mucosal routes, has often led to serious adverse effects. Therefore, the alternative use of delivery systems to deliver antigen in APC after mucosal administration is more and more studied.Antigen delivery systems include immunomodulating particles, and inert delivery systems. The first ones can enhance the mucosal antigen bioavailability by vectorizing antigens to APC, and at the same time trigger intracellular pro-inflammatory pathways, to drive the Th1/Th2 immune balance. Among them, virus-like particles (VLP), saponin-based emulsions (ISCOMs) or MPL-containing liposomes are the most represented in clinical trials. However, their mucosal administration can lead to the same adverse effects than classical immunostimulating molecules. In parallel, true delivery systems can enhance the antigens immunogenicity by increasing their intracellular delivery, thus mimicking a natural infection. They are therefore far less toxic for the mucosa than immunomodulating particles but need to be more efficient in the mucus penetration, in the antigen association and in the APC intracellular delivery.During this thesis, we deciphered the mechanisms allowing cationic and lipidated maltodextrine nanoparticles (NPL) to deliver antigens after nasal administration.We first evaluated the ability of NPL to cross the airway mucus barrier, compared to mucopenetrant particles (PEG-coated PLGA or PLGA-PEG) and mucoadherent particles (chitosan-coated PLGA or PLGA-CS), by measuring their displacement in reconstituted mucus. We observed that in presence of the phospholipid core, the NPL were able to move in the mucus, while PLGA-CS NPs remained stuck in the gel. Moreover, we observed that the NPL uptake and the protein delivery in airway epithelial cells were not impaired by the presence of mucins, contrary to PLGA-CS that were hindered by the mucins, and to PLGA-PEG which were not taken up by the cells, due to their neutral surface charge. We finally demonstrated that the NPL mucopenetration was allowed thanks to steric and repulsive electrostatic forces between the anionic phospholipid core and the mucins.In parallel, we studied the mechanisms allowing the NPL to enhance the immunogenicity of subunit antigens after nasal administration, with a highlight on the importance of the NP’s density [...]

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Halladay, Jeff. "Chitosan nanoparticles for mucosal and intramuscular delivery of DNA vaccines." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/17267.

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Somavarapu, Satyanarayana. "Novel bioadhesive formulations for mucosal and parenteral delivery of vaccines." Thesis, Aston University, 2001. http://publications.aston.ac.uk/12366/.

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In this work we have established the efficient mucosal delivery of vaccines using absorption enhancers and chitosan. In addition, the use of chitosan was shown to enhance the action of other known adjuvants, such as CTB or Quil-A. Collectively, the results presented herein indicate that chitosan has excellent potential as a mucosal adjuvant. We have evaluated a number of absorption enhancers for their adjuvant activity in vivo. Polyornithine was shown to engender high scrum immune reasons to nasally delivered antigens, with higher molecular weight polyornithine facilitating the best results. We have demonstrated for the first time that vitamin E TPGS can act as mucosal adjuvant. Deoxycholic acid, cyclodextrins and acylcarnitines were also identified as effective mucosal adjuvants and showed enhanced immune responses to nasally delivered TT, DT and Yersinia pestis V and F1 antigens. Previously, none of these agents, common in their action as absorption enhancing agents, have been shown to have immunopotentiating activity for mucosal immunisation. We have successfully developed novel surface modified microspheres using chitosan as an emulsion stabiliser during the preparation of PLA microspheres. It was found that immune responses could be substantially increased, effectively exploiting the immunopenetrating characteristics of both chitosan and PLA microspheres in the same delivery vehicle. In the same study, comparison of intranasal and intramuscular routes of administration showed that with these formulations, the nasal route could be as effective as intramuscular delivery, highlighting the potential of mucosal administration for these particulate delivery systems Chitosan was co-administered with polymer microspheres. It was demonstrated that this strategy facilitates markedly enhanced immune responses in both magnitude and duration following intramuscular administration. We conclude that this combination shows potential for single dose administration of vaccines. In another study, we have shown that the addition of chitosan to alum adsorbed TT was able to enhance immune responses. PLA micro/nanospheres were prepared and characterised with discreet particle size ranges. A smaller particle size was shown to facilitate higher scrum IgG responses following nasal administration. A lower antigen loading was additionally identified as being preferential for the induction of immune responses in combination with the smaller particle size.

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Hu, Ke-Fei. "ISCOMs as delivery systems for mucosal immunization /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5417-4.pdf.

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Ferreira, Ewerton Lucena. "Desenvolvimento de uma nova estratégia vacinal contra a cárie dental humana baseada na proteína PstS de Streptococcus mutans." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/42/42132/tde-26082015-151741/.

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Streptococcus mutans é o principal agente etiológico da cárie dental humana, uma doença infecciosa para a qual não há vacina disponível. A influência dos sistemas de transporte ABC na virulência bacteriana suporta seu uso como alvos vacinais. Em S. mutans a proteína ligadora de fosfato (PstS) influencia a expressão de fatores de virulência. A proposta deste trabalho foi caracterizar uma estratégia vacinal de mucosa anti-cárie baseada na proteína PstS como antígeno alvo. Inicialmente, a forma recombinante da proteína foi obtida em E. coli. A caracterização biofísica revelou uma estrutura secundária estável, semelhante a outras proteínas ligadoras e capaz de interagir com seu ligante. Epítopos antigênicos conservados foram identificados na proteína recombinante pela reatividade com soro anti-S. mutans. A proteína rPstS foi imunogênica por via sublingual, combinada ou não à LTK4R e anticorpos rPstS-específicos interferiram na colonização oral in vivo por S. mutans. Os resultados indicam que a proteína rPstS pode ser explorada em estratégias vacinais contra a cárie.
Streptococcus mutans is the main etiological agent of human dental caries, an infectious disease for which there is no vaccine available. The influence of ABC transport systems in bacterial virulence supports its use as vaccine targets. In S. mutans the phosphate binding protein (PstS) influences the expression of virulence traits. The purpose of this work was characterizing an anti-caries mucosal vaccine based on the PstS protein as target antigen. First, a recombinant form of the protein was obtained in E. coli. The biophysical characterization showed a stable secondary structure, similar to other binding proteins and able to interact with its ligand. Conserved antigenic epitopes were identified in the recombinant protein by reactivity with anti- S. mutans serum. The rPstS protein was immunogenic by the sublingual route in combination or not with LTK4R and rPstS-specific antibodies interfered with S. mutans oral colonization in vivo. The results indicated that the recombinant PstS protein can be exploited in vaccine strategies against dental caries.

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Dissertations / Theses on the topic 'Mucosal vaccine'

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