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Sample records for antigenic peptide vaccine

  1. Current status of multiple antigen-presenting peptide vaccine systems: Application of organic and inorganic nanoparticles

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    Taguchi Hiroaki

    2011-08-01

    Full Text Available Abstract Many studies are currently investigating the development of safe and effective vaccines to prevent various infectious diseases. Multiple antigen-presenting peptide vaccine systems have been developed to avoid the adverse effects associated with conventional vaccines (i.e., live-attenuated, killed or inactivated pathogens, carrier proteins and cytotoxic adjuvants. Recently, two main approaches have been used to develop multiple antigen-presenting peptide vaccine systems: (1 the addition of functional components, e.g., T-cell epitopes, cell-penetrating peptides, and lipophilic moieties; and (2 synthetic approaches using size-defined nanomaterials, e.g., self-assembling peptides, non-peptidic dendrimers, and gold nanoparticles, as antigen-displaying platforms. This review summarizes the recent experimental studies directed to the development of multiple antigen-presenting peptide vaccine systems.

  2. MHC-restricted antigen presentation and recognition: constraints on gene, recombinant and peptide vaccines in humans

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    Cunha-Neto E.

    1999-01-01

    Full Text Available The target of any immunization is to activate and expand lymphocyte clones with the desired recognition specificity and the necessary effector functions. In gene, recombinant and peptide vaccines, the immunogen is a single protein or a small assembly of epitopes from antigenic proteins. Since most immune responses against protein and peptide antigens are T-cell dependent, the molecular target of such vaccines is to generate at least 50-100 complexes between MHC molecule and the antigenic peptide per antigen-presenting cell, sensitizing a T cell population of appropriate clonal size and effector characteristics. Thus, the immunobiology of antigen recognition by T cells must be taken into account when designing new generation peptide- or gene-based vaccines. Since T cell recognition is MHC-restricted, and given the wide polymorphism of the different MHC molecules, distinct epitopes may be recognized by different individuals in the population. Therefore, the issue of whether immunization will be effective in inducing a protective immune response, covering the entire target population, becomes an important question. Many pathogens have evolved molecular mechanisms to escape recognition by the immune system by variation of antigenic protein sequences. In this short review, we will discuss the several concepts related to selection of amino acid sequences to be included in DNA and peptide vaccines.

  3. Optimized tumor cryptic peptides: the basis for universal neo-antigen-like tumor vaccines.

    Science.gov (United States)

    Menez-Jamet, Jeanne; Gallou, Catherine; Rougeot, Aude; Kosmatopoulos, Kostas

    2016-07-01

    The very impressive clinical results recently obtained in cancer patients treated with immune response checkpoint inhibitors boosted the interest in immunotherapy as a therapeutic choice in cancer treatment. However, these inhibitors require a pre-existing tumor specific immune response and the presence of tumor infiltrating T cells to be efficient. This immune response can be triggered by cancer vaccines. One of the main issues in tumor vaccination is the choice of the right antigen to target. All vaccines tested to date targeted tumor associated antigens (TAA) that are self-antigens and failed to show a clinical efficacy because of the immune self-tolerance to TAA. A new class of tumor antigens has recently been described, the neo-antigens that are created by point mutations of tumor expressing proteins and are recognized by the immune system as non-self. Neo-antigens exhibit two main properties: they are not involved in the immune self-tolerance process and are immunogenic. However, the majority of the neo-antigens are patient specific and their use as cancer vaccines requires their previous identification in each patient individualy that can be done only in highly specialized research centers. It is therefore evident that neo-antigens cannot be used for patient vaccination worldwide. This raises the question of whether we can find neo-antigen like vaccines, which would not be patient specific. In this review we show that optimized cryptic peptides from TAA are neo-antigen like peptides. Optimized cryptic peptides are recognized by the immune system as non-self because they target self-cryptic peptides that escape self-tolerance; in addition they are strongly immunogenic because their sequence is modified in order to enhance their affinity for the HLA molecule. The first vaccine based on the optimized cryptic peptide approach, Vx-001, which targets the widely expressed tumor antigen telomerase reverse transcriptase (TERT), has completed a large phase I clinical

  4. Presenting a foreign antigen on live attenuated Edwardsiella tarda using twin-arginine translocation signal peptide as a multivalent vaccine.

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    Wang, Yamin; Yang, Weizheng; Wang, Qiyao; Qu, Jiangbo; Zhang, Yuanxing

    2013-12-01

    The twin-arginine translocation (Tat) system is a major pathway for transmembrane translocation of fully folded proteins. In this study, a multivalent vaccine to present foreign antigens on live attenuated vaccine Edwardsiella tarda WED using screened Tat signal peptide was constructed. Because the Tat system increases the yields of folded antigens in periplasmic space or extracellular milieu, it is expected to contribute to the production of conformational epitope-derived specific antibodies. E. tarda Tat signal peptides fused with the green fluorescent protein (GFP) was constructed under the control of an in vivo inducible dps promoter. The resulting plasmids were electroporated into WED and the subcellular localizations of GFP were analyzed with Western blotting. Eight signal peptides with optimized GFP translocation efficiency were further fused to a protective antigen glyceraldehyde-3-phosphate dehydrogenase (GapA) from a fish pathogen Aeromonas hydrophila. Signal peptides of DmsA, NapA, and SufI displayed high efficiency for GapA translocation. The relative percent survival (RPS) of turbot was measured with a co-infection of E. tarda and A. hydrophila, and the strain with DmsA signal peptide showed the maximal protection. This study demonstrated a new platform to construct multivalent vaccines using optimized Tat signal peptide in E. tarda. PMID:23994481

  5. Synthetic peptide vaccines: palmitoylation of peptide antigens by a thioester bond increases immunogenicity

    DEFF Research Database (Denmark)

    Beekman, N.J.C.M.; Schaaper, W.M.M.; Tesser, G.I.;

    1997-01-01

    or an amide bond. It was found that these S-palmitoylated peptides were much more immunogenic than N-palmitoylated peptides and at least similar to KLH-conjugated peptides with respect to appearance and magnitude of induced antibodies (canine parvovirus) or immunocastration effect (gonadotropin...

  6. Presentation of peptides from Bacillus anthracis protective antigen on Tobacco Mosaic Virus as an epitope targeted anthrax vaccine.

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    McComb, Ryan C; Ho, Chi-Lee; Bradley, Kenneth A; Grill, Laurence K; Martchenko, Mikhail

    2015-11-27

    The current anthrax vaccine requires improvements for rapidly invoking longer-lasting neutralizing antibody responses with fewer doses from a well-defined formulation. Designing antigens that target neutralizing antibody epitopes of anthrax protective antigen, a component of anthrax toxin, may offer a solution for achieving a vaccine that can induce strong and long lasting antibody responses with fewer boosters. Here we report implementation of a strategy for developing epitope focused virus nanoparticle vaccines against anthrax by using immunogenic virus particles to present peptides derived from anthrax toxin previously identified in (1) neutralizing antibody epitope mapping studies, (2) toxin crystal structure analyses to identify functional regions, and (3) toxin mutational analyses. We successfully expressed two of three peptide epitopes from anthrax toxin that, in previous reports, bound antibodies that were partially neutralizing against toxin activity, discovered cross-reactivity between vaccine constructs and toxin specific antibodies raised in goats against native toxin and showed that antibodies induced by our vaccine constructs also cross-react with native toxin. While protection against intoxication in cellular and animal studies were not as effective as in previous studies, partial toxin neutralization was observed in animals, demonstrating the feasibility of using plant-virus nanoparticles as a platform for epitope defined anthrax vaccines. PMID:26514421

  7. Loss of T Cell Antigen Recognition Arising from Changes in Peptide and Major Histocompatibility Complex Protein Flexibility: Implications for Vaccine Design

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    Insaidoo, Francis K.; Borbulevych, Oleg Y.; Hossain, Moushumi; Santhanagopolan, Sujatha M.; Baxter, Tiffany K.; Baker, Brian M. (Notre)

    2012-05-08

    Modification of the primary anchor positions of antigenic peptides to improve binding to major histocompatibility complex (MHC) proteins is a commonly used strategy for engineering peptide-based vaccine candidates. However, such peptide modifications do not always improve antigenicity, complicating efforts to design effective vaccines for cancer and infectious disease. Here we investigated the MART-1{sub 27-35} tumor antigen, for which anchor modification (replacement of the position two alanine with leucine) dramatically reduces or ablates antigenicity with a wide range of T cell clones despite significantly improving peptide binding to MHC. We found that anchor modification in the MART-1{sub 27-35} antigen enhances the flexibility of both the peptide and the HLA-A*0201 molecule. Although the resulting entropic effects contribute to the improved binding of the peptide to MHC, they also negatively impact T cell receptor binding to the peptide {center_dot} MHC complex. These results help explain how the 'anchor-fixing' strategy fails to improve antigenicity in this case, and more generally, may be relevant for understanding the high specificity characteristic of the T cell repertoire. In addition to impacting vaccine design, modulation of peptide and MHC flexibility through changes to antigenic peptides may present an evolutionary strategy for the escape of pathogens from immune destruction.

  8. Redefining an epitope of a malaria vaccine candidate, with antibodies against the N-terminal MSA-2 antigen of Plasmodium harboring non-natural peptide bonds

    OpenAIRE

    Lozano, José Manuel; Guerrero, Yuly Andrea; Alba, Martha Patricia; Lesmes, Liliana Patricia; Escobar, José Oswaldo; Patarroyo, Manuel Elkin

    2013-01-01

    The aim of obtaining novel vaccine candidates against malaria and other transmissible diseases can be partly based on selecting non-polymorphic peptides from relevant antigens of pathogens, which have to be then precisely modified for inducing a protective immunity against the disease. Bearing in mind the high degree of the MSA-221–40 peptide primary structure’s genetic conservation among malaria species, and its crucial role in the high RBC binding ability of Plasmodium falciparum (the main ...

  9. Peptide Vaccine: Progress and Challenges

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    Weidang Li

    2014-07-01

    Full Text Available Conventional vaccine strategies have been highly efficacious for several decades in reducing mortality and morbidity due to infectious diseases. The bane of conventional vaccines, such as those that include whole organisms or large proteins, appear to be the inclusion of unnecessary antigenic load that, not only contributes little to the protective immune response, but complicates the situation by inducing allergenic and/or reactogenic responses. Peptide vaccines are an attractive alternative strategy that relies on usage of short peptide fragments to engineer the induction of highly targeted immune responses, consequently avoiding allergenic and/or reactogenic sequences. Conversely, peptide vaccines used in isolation are often weakly immunogenic and require particulate carriers for delivery and adjuvanting. In this article, we discuss the specific advantages and considerations in targeted induction of immune responses by peptide vaccines and progresses in the development of such vaccines against various diseases. Additionally, we also discuss the development of particulate carrier strategies and the inherent challenges with regard to safety when combining such technologies with peptide vaccines.

  10. Antigen-Specific CD4+ T Cells Recognize Epitopes of Protective Antigen following Vaccination with an Anthrax Vaccine

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    Laughlin, Elsa M.; Miller, Joseph D.; James, Eddie; Fillos, Dimitri; Ibegbu, Chris C.; Mittler, Robert S.; Akondy, Rama; Kwok, William; Ahmed, Rafi; Nepom, Gerald,

    2007-01-01

    Detection of antigen-specific CD4+ T cells is facilitated by the use of fluorescently labeled soluble peptide-major histocompatibility complex (MHC) multimers which mirror the antigen specificity of T-cell receptor recognition. We have used soluble peptide-MHC class II tetramers containing peptides from the protective antigen (PA) of Bacillus anthracis to detect circulating T cells in peripheral blood of subjects vaccinated with an anthrax vaccine. PA-specific HLA class II-restricted T lympho...

  11. Vesicular Stomatitis Virus glycoprotein G carrying a tandem dimer of Foot and Mouth Disease Virus antigenic site A can be used as DNA and peptide vaccine for cattle.

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    Capozzo, Alejandra V; Wilda, Maximiliano; Bucafusco, Danilo; de los Ángeles Lavoria, María; Franco-Mahecha, Olga L; Mansilla, Florencia C; Pérez-Filgueira, Daniel M; Grigera, Pablo R

    2011-11-01

    Effective Foot and Mouth Disease Virus (FMDV) peptide vaccines for cattle have two major constraints: resemblance of one or more of the multiple conformations of the major VP1 antigenic sites to induce neutralizing antibodies, and stimulation of T cells despite the variable bovine-MHC polymorphism. To overcome these limitations, a chimeric antigen was developed, using Vesicular Stomatitis Virus glycoprotein (VSV-G) as carrier protein of an in tandem-dimer of FMDV antigenic site A (ASA), the major epitope on the VP1 capsid protein (aa 139-149, FMDV-C3 serotype). The G-ASA construct was expressed in the Baculovirus system to produce a recombinant protein (DEL BAC) (cloned in pCDNA 3.1 plasmid) (Invitrogen Corporation, Carlsbad, CA) and was also prepared as a DNA vaccine (pC DEL). Calves vaccinated with both immunogens elicited antibodies that recognized the ASA in whole virion and were able to neutralize FMDV infectivity in vitro. After two vaccine doses, DEL BAC induced serum neutralizing titers compatible with an "expected percentage of protection" above 90%. Plasmid pC DEL stimulated FMDV specific humoral responses earlier than DEL BAC, though IgG1 to IgG2 ratios were lower than those induced by both DEL BAC and inactivated FMDV-C3 after the second dose. DEL BAC induced FMDV-specific secretion of IFN-γ in peripheral blood mononuclear cells of outbred cattle immunized with commercial FMDV vaccine, suggesting its capacity to recall anamnestic responses mediated by functional T cell epitopes. The results show that exposing FMDV-VP1 major neutralizing antigenic site in the context of N-terminal sequences of the VSV G protein can overcome the immunological limitations of FMDV-VP1 peptides as effective protein and DNA vaccines for cattle. PMID:21889542

  12. Tumor Antigen-Derived Peptides Delivery for Cancer Immunotherapy.

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    Wenxue, Ma

    2014-02-05

    Tumor antigenic peptides therapeutics is a promising field for cancer immunotherapy. Benefits include the ease and rapid synthesis of antigenic peptides and capacity for modifications. In the past years, many peptide-based cancer vaccines have been tested in clinical trials with a limited success because of the difficulties associated with peptide stability and delivery approaches, consequently, resulting in inefficient antigen presentation and low response rates in patients with cancer. The development of suitable and efficient vaccine carrier systems still remains a major challenge. This article aims to describe a new delivery approach for tumor antigenic peptides and rationales of dendritic cells (DCs)-based vaccination. In order to elicit enhanced immune responses, poly(DL-lactide-co-glycolide) (PLGA), which has been approved by the US Food and Drug Administration (FDA) for the use of drug delivery, diagnostics and other applications of clinical and basic science research were employed for the formulation of making nanoparticles (NPs) while delivering tumor antigenic peptides.

  13. Therapeutic HIV Peptide Vaccine

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    Fomsgaard, Anders

    2015-01-01

    infection directed to subdominant conserved HIV-1 epitopes restricted to frequent HLA supertypes. The rationale for selecting HIV peptides and adjuvants are provided. Peptide subunit vaccines are regarded as safe due to the simplicity, quality, purity, and low toxicity. The caveat is reduced immunogenicity......Therapeutic vaccines aim to control chronic HIV infection and eliminate the need for lifelong antiretroviral therapy (ART). Therapeutic HIV vaccine is being pursued as part of a functional cure for HIV/AIDS. We have outlined a basic protocol for inducing new T cell immunity during chronic HIV-1...... and hence adjuvants are included to enhance and direct the immune response. Although the vaccine has been tested in ART naïve individuals, we recommend future testing of the vaccine during (early started) ART that improves immune function and to select individuals likely to benefit. Peptides representing...

  14. Hepatitis C Virus Subtype 3a Envelope Protein 1 Binding with Human Leukocyte Antigen Class I Types of Pakistani Population: Candidate Epitopes for Synthetic Peptide Vaccine.

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    Nawaz-Tipu, Hamid

    2015-10-01

    The object of this cross sectional study was to determine the HCV subtype 3a envelope protein binding affinity with Human Leukocyte Antigen. Envelope 1 (E1) protein is one of the structural proteins responsible for entering the cells through the receptors. The binding affinity of E1 protein epitopes to the selected Human Leukocyte Antigen (HLA) class I alleles was investigated using the computer-based tools. These prediction tools were also used to design the synthetic vaccine's candidate epitopes and to identify the individuals/populations who are likely to be responder to those vaccines.The mean frequency of HLA I antigens in Pakistani population was calculated. Three alleles each from HLA A and B were selected. E1 protein sequence extracted from HCV 3a isolates was retrieved and twenty-four sequences of it were selected. NetMHCcons 1.0 server was used to determine the binding affinities of HLA alleles to the epitope sequences of 10 amino acids in length.A02, A03, A11, A24, A33, B08, B13, B15, B35 and B40 were the first five antigens more prevalent in Pakistan each from HLA A and HLA B.. We did not find any binding affinity between HLA A*201, B*1501 and B*4001 and epitopes from E1 sequences in a threshold of 50 nM. Totally five various epitopes derived from different isolates were characterized.The prediction of HLA-E1 epitope specific bindings and the forthcoming response can be a useful bioinformatics tool to uncover the right synthetic peptides for vaccine design purposes.

  15. Hepatitis C Virus Subtype 3a Envelope Protein 1 Binding with Human Leukocyte Antigen Class I Types of Pakistani Population: Candidate Epitopes for Synthetic Peptide Vaccine

    Directory of Open Access Journals (Sweden)

    Hamid Nawaz-Tipu

    2015-10-01

    Full Text Available The object of this cross sectional study was to determine the HCV subtype 3a envelope protein binding affinity with Human Leukocyte Antigen. Envelope 1 (E1 protein is one of the structural proteins responsible for entering the cells through the receptors. The binding affinity of E1 protein epitopes to the selected Human Leukocyte Antigen (HLA class I alleles was investigated using the computer-based tools. These prediction tools were also used to design the synthetic vaccine’s candidate epitopes and to identify the individuals/populations who are likely to be responder to those vaccines.The mean frequency of HLA I antigens in Pakistani population was calculated. Threealleles each from HLA A and B were selected. E1 protein sequence extracted from HCV 3a isolates was retrieved and twenty-four sequences of it were selected. NetMHCcons 1.0 server was used to determine the binding affinities of HLA alleles to the epitope sequences of 10 amino acids in length.A02, A03, A11, A24, A33, B08, B13, B15, B35 and B40 were the first five antigens moreprevalent in Pakistan each from HLA A and HLA B.. We did not find any binding affinity between HLA A*201, B*1501 and B*4001 and epitopes from E1 sequences in a threshold of50 nM. Totally five various epitopes derived from different isolates were characterized.The prediction of HLA-E1 epitope specific bindings and the forthcoming response can be a useful bioinformatics tool to uncover the right synthetic peptides for vaccine design purposes.

  16. High-affinity human leucocyte antigen class I binding variola-derived peptides induce CD4(+) T cell responses more than 30 years post-vaccinia virus vaccination

    DEFF Research Database (Denmark)

    Wang, M.; Tang, Sheila Tuyet; Lund, Ole;

    2009-01-01

    Interferon-gamma secreting T lymphocytes against pox virus-derived synthetic 9-mer peptides were tested by enzyme-linked immunospot in peripheral blood of individuals vaccinated with vaccinia virus more than 30 years ago. The peptides were characterized biochemically as high-affinity human...

  17. A phase II trial of personalized peptide vaccination in castration-resistant prostate cancer patients: prolongation of prostate-specific antigen doubling time

    OpenAIRE

    Noguchi, Masanori; MORIYA, FUKUKO; SUEKANE, SHIGETAKA; Ohnishi, Rei; Matsueda, Satoko; Sasada, Tetsuro; Yamada, Akira; Itoh, Kyogo

    2013-01-01

    Background Cancer vaccine is one of the attractive treatment modalities for patients with castration-resistant prostate cancer (CRPC). However, because of delayed immune responses, its clinical benefits, besides for overall survival (OS), are not well captured by the World Health Organization (WHO) and Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Several surrogate markers for evaluation of cancer vaccine, including prostate-specific antigen doubling time (PSADT), are curren...

  18. Selection of glutamate-rich protein long synthetic peptides for vaccine development: antigenicity and relationship with clinical protection and immunogenicity

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    Theisen, M; Dodoo, D; Toure-Balde, A;

    2001-01-01

    Antibodies against three long synthetic peptides (LSPs) derived from the glutamate-rich protein (GLURP) of Plasmodium falciparum were analyzed in three cohorts from Liberia, Ghana, and Senegal. Two overlapping LSPs, LR67 and LR68, are derived from the relatively conserved N-terminal nonrepeat...... from clinical P. falciparum malaria. Protected children from the Ghana cohort possessed predominantly IgG1 antibodies against the nonrepeat epitope and IgG3 antibodies against the repeat epitope. T-cell proliferation responses, studied in the cohort from Senegal, revealed that T-helper-cell epitopes...

  19. Vaccination with NY-ESO-1 overlapping peptides mixed with Picibanil OK-432 and montanide ISA-51 in patients with cancers expressing the NY-ESO-1 antigen.

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    Wada, Hisashi; Isobe, Midori; Kakimi, Kazuhiro; Mizote, Yu; Eikawa, Shingo; Sato, Eiichi; Takigawa, Nagio; Kiura, Katsuyuki; Tsuji, Kazuhide; Iwatsuki, Keiji; Yamasaki, Makoto; Miyata, Hiroshi; Matsushita, Hirokazu; Udono, Heiichiro; Seto, Yasuyuki; Yamada, Kazuhiro; Nishikawa, Hiroyoshi; Pan, Linda; Venhaus, Ralph; Oka, Mikio; Doki, Yuichiro; Nakayama, Eiichi

    2014-01-01

    We conducted a clinical trial of an NY-ESO-1 cancer vaccine using 4 synthetic overlapping long peptides (OLP; peptides #1, 79-108; #2, 100-129; #3, 121-150; and #4, 142-173) that include a highly immunogenic region of the NY-ESO-1 molecule. Nine patients were immunized with 0.25 mg each of three 30-mer and a 32-mer long NY-ESO-1 OLP mixed with 0.2 KE Picibanil OK-432 and 1.25 mL Montanide ISA-51. The primary endpoints of this study were safety and NY-ESO-1 immune responses. Five to 18 injections of the NY-ESO-1 OLP vaccine were well tolerated. Vaccine-related adverse events observed were fever and injection site reaction (grade 1 and 2). Two patients showed stable disease after vaccination. An NY-ESO-1-specific humoral immune response was observed in all patients and an antibody against peptide #3 (121-150) was detected firstly and strongly after vaccination. NY-ESO-1 CD4 and CD8 T-cell responses were elicited in these patients and their epitopes were identified. Using a multifunctional cytokine assay, the number of single or double cytokine-producing cells was increased in NY-ESO-1-specific CD4 and CD8 T cells after vaccination. Multiple cytokine-producing cells were observed in PD-1 (-) and PD-1 (+) CD4 T cells. In conclusion, our study indicated that the NY-ESO-1 OLP vaccine mixed with Picibanil OK-432 and Montanide ISA-51 was well tolerated and elicited NY-ESO-1-specific humoral and CD4 and CD8 T-cell responses in immunized patients.

  20. Injectable polymer microspheres enhance immunogenicity of a contraceptive peptide vaccine

    OpenAIRE

    Cui, Chengji; Stevens, Vernon C.; Schwendeman, Steven P.

    2006-01-01

    Advanced contraceptive peptide vaccines suffer from the unavailability of adjuvants capable of enhancing the antibody response with acceptable safety. We sought to overcome this limitation by employing two novel poly(lactic-co-glycolic acid) (PLGA) microsphere formulations to deliver a synthetic human chorionic gonadotropin (hCG) peptide antigen co-synthesized with a T-cell epitope from tetanus toxoid, C-TT2-CTP35: surface-conjugated immunogen to induce phagocytosis; and encapsulated peptide ...

  1. Meningococcal vaccine antigen diversity in global databases.

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    Brehony, Carina; Hill, Dorothea M; Lucidarme, Jay; Borrow, Ray; Maiden, Martin C

    2015-01-01

    The lack of an anti-capsular vaccine against serogroup B meningococcal disease has necessitated the exploration of alternative vaccine candidates, mostly proteins exhibiting varying degrees of antigenic variation. Analysis of variants of antigen-encoding genes is facilitated by publicly accessible online sequence repositories, such as the Neisseria PubMLST database and the associated Meningitis Research Foundation Meningococcus Genome Library (MRF-MGL). We investigated six proposed meningococcal vaccine formulations by deducing the prevalence of their components in the isolates represented in these repositories. Despite high diversity, a limited number of antigenic variants of each of the vaccine antigens were prevalent, with strong associations of particular variant combinations with given serogroups and genotypes. In the MRF-MGL and globally, the highest levels of identical sequences were observed with multicomponent/multivariant vaccines. Our analyses further demonstrated that certain combinations of antigen variants were prevalent over periods of decades in widely differing locations, indicating that vaccine formulations containing a judicious choice of antigen variants have potential for long-term protection across geographic regions. The data further indicated that formulations with multiple variants would be especially relevant at times of low disease incidence, as relative diversity was higher. Continued surveillance is required to monitor the changing prevalence of these vaccine antigens. PMID:26676305

  2. Long-Term Follow-Up of HLA-A2+ Patients with High-Risk, Hormone-Sensitive Prostate Cancer Vaccinated with the Prostate Specific Antigen Peptide Homologue (PSA146-154

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    Supriya Perambakam

    2010-01-01

    Full Text Available Twenty-eight HLA-A2+ patients with high-risk, locally advanced or metastatic, hormone-sensitive prostate cancer were immunized with a peptide homologue of prostate-specific antigen, PSA146-154, between July 2002 and September 2004 and monitored for clinical and immune responses. Fifty percent of the patients developed strong PSA146-154-peptide-specific delayed-type hypersensitivity skin responses, tetramer and/or IFN-γ responses within one year. Thirteen patients had stable or declining serum levels of PSA one year post-vaccination. A decreased risk of biochemical progression was observed in patients who developed augmented tetramer responses at six months compared to pre-vaccination levels (P=.02. Thirteen patients have died while 15 patients remain alive with a mean overall survival of 60 months (95% CI, 51 to 68 months per Kaplan-Meier analysis. A trend towards greater overall survival was detected in men with high-risk, hormone-sensitive CaP who developed specific T-cell immunity following vaccination with PSA146-154 peptide.

  3. CELLULAR VACCINES IN LISTERIOSIS: ROLE OF THE LISTERIA ANTIGEN GAPDH.

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    Ricardo eCalderon-Gonzalez

    2014-02-01

    Full Text Available The use of live Listeria-based vaccines carries serious difficulties when administrated to immunocompromised individuals. However, cellular carriers have the advantage of inducing multivalent innate immunity as well as cell-mediated immune responses, constituting novel and secure vaccine strategies in listeriosis. Here, we compare the protective efficacy of dendritic cells (DCs and macrophages and their safety. We examined the immune response of these vaccine vectors using two Listeria antigens, listeriolysin O (LLO and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH, and several epitopes such as the LLO peptides, LLO189–201 and LLO91–99 and the GAPDH peptide, GAPDH1–22. We discarded macrophages as safe vaccine vectors because they show anti-Listeria protection but also high cytotoxicity. DCs loaded with GAPDH1–22 peptide conferred higher protection and security against listeriosis than the widely explored LLO91–99 peptide. Anti-Listeria protection was related to the changes in DC maturation caused by these epitopes, with high production of interleukin-12 as well as significant levels of other Th1 cytokines such as monocyte chemotactic protein-1, tumor necrosis factor-α, and interferon-γ, and with the induction of GAPDH1–22-specific CD4+ and CD8+ immune responses. This is believed to be the first study to explore the use of a novel GAPDH antigen as a potential DC-based vaccine candidate for listeriosis, whose efficiency appears to highlight the relevance of vaccine designs containing multiple CD4+ and CD8+ epitopes.

  4. Cellular vaccines in listeriosis: role of the Listeria antigen GAPDH.

    Science.gov (United States)

    Calderón-González, Ricardo; Frande-Cabanes, Elisabet; Bronchalo-Vicente, Lucía; Lecea-Cuello, M Jesús; Pareja, Eduardo; Bosch-Martínez, Alexandre; Fanarraga, Mónica L; Yañez-Díaz, Sonsoles; Carrasco-Marín, Eugenio; Alvarez-Domínguez, Carmen

    2014-01-01

    The use of live Listeria-based vaccines carries serious difficulties when administrated to immunocompromised individuals. However, cellular carriers have the advantage of inducing multivalent innate immunity as well as cell-mediated immune responses, constituting novel and secure vaccine strategies in listeriosis. Here, we compare the protective efficacy of dendritic cells (DCs) and macrophages and their safety. We examined the immune response of these vaccine vectors using two Listeria antigens, listeriolysin O (LLO) and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH), and several epitopes such as the LLO peptides, LLO189-201 and LLO91-99 and the GAPDH peptide, GAPDH1-22. We discarded macrophages as safe vaccine vectors because they show anti-Listeria protection but also high cytotoxicity. DCs loaded with GAPDH1-22 peptide conferred higher protection and security against listeriosis than the widely explored LLO91-99 peptide. Anti-Listeria protection was related to the changes in DC maturation caused by these epitopes, with high production of interleukin-12 as well as significant levels of other Th1 cytokines such as monocyte chemotactic protein-1, tumor necrosis factor-α, and interferon-γ, and with the induction of GAPDH1-22-specific CD4(+) and CD8(+) immune responses. This is believed to be the first study to explore the use of a novel GAPDH antigen as a potential DC-based vaccine candidate for listeriosis, whose efficiency appears to highlight the relevance of vaccine designs containing multiple CD4(+) and CD8(+) epitopes.

  5. Cellular vaccines in listeriosis: role of the Listeria antigen GAPDH

    Science.gov (United States)

    Calderón-González, Ricardo; Frande-Cabanes, Elisabet; Bronchalo-Vicente, Lucía; Lecea-Cuello, M. Jesús; Pareja, Eduardo; Bosch-Martínez, Alexandre; Fanarraga, Mónica L.; Yañez-Díaz, Sonsoles; Carrasco-Marín, Eugenio; Álvarez-Domínguez, Carmen

    2014-01-01

    The use of live Listeria-based vaccines carries serious difficulties when administrated to immunocompromised individuals. However, cellular carriers have the advantage of inducing multivalent innate immunity as well as cell-mediated immune responses, constituting novel and secure vaccine strategies in listeriosis. Here, we compare the protective efficacy of dendritic cells (DCs) and macrophages and their safety. We examined the immune response of these vaccine vectors using two Listeria antigens, listeriolysin O (LLO) and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH), and several epitopes such as the LLO peptides, LLO189−201 and LLO91−99 and the GAPDH peptide, GAPDH1−22. We discarded macrophages as safe vaccine vectors because they show anti-Listeria protection but also high cytotoxicity. DCs loaded with GAPDH1−22 peptide conferred higher protection and security against listeriosis than the widely explored LLO91−99 peptide. Anti-Listeria protection was related to the changes in DC maturation caused by these epitopes, with high production of interleukin-12 as well as significant levels of other Th1 cytokines such as monocyte chemotactic protein-1, tumor necrosis factor-α, and interferon-γ, and with the induction of GAPDH1−22-specific CD4+ and CD8+ immune responses. This is believed to be the first study to explore the use of a novel GAPDH antigen as a potential DC-based vaccine candidate for listeriosis, whose efficiency appears to highlight the relevance of vaccine designs containing multiple CD4+ and CD8+ epitopes. PMID:24600592

  6. Cysteine proteases as potential antigens in antiparasitic DNA vaccines

    DEFF Research Database (Denmark)

    Jørgensen, Louise von Gersdorff; Buchmann, Kurt

    2011-01-01

    En litteraturgennemgang af muligheder for at bruge cystein proteaser som antigener i antiparasitære vacciner.......En litteraturgennemgang af muligheder for at bruge cystein proteaser som antigener i antiparasitære vacciner....

  7. A systems biology perspective on rational design of peptide vaccine against virus infections.

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    Chen, Jiajia; Wang, Ying; Guo, Deyin; Shen, Bairong

    2012-01-01

    With the recent onset of influenza A (H1N1) pandemic, the need for improved vaccines against virus infections has become an international priority. Strategies for vaccine development have changed over time, from whole-virus to immunogenic proteins and further to antigenic viral peptides. Various algorithms and bioinformatics tools have been developed to predict immunogenic peptide regions in an antigenic protein sequence. Recent advances in next-generation sequencing technologies, as represented by real time DNA sequencing, provide increased throughput and yield of data on viral pathogens and host cells. This enables us to 'mine' the genomic sequence for putative vaccine candidates or targets, allowing a more rational approach to the peptide vaccine design. This review first describes current computational tools available for the rational design of peptide vaccines and then addresses recent attempts to define pathogenic peptides at '- omics' level. As there are interplay between antibody and T cells, as well as intersection between viruses and hosts, the vaccine-mediated immunity are orchestrated by multiple factors within an interaction network. Therefore, single viral peptide alone fails to provide optimal immunity. Systems biology offers a systems-level perspective of how the various arms of the immune response are integrated to give immune response, as well as how host and virus interact, thereby providing an integrated approach to select the most promising candidates for peptide vaccines development. We highlight in this article the system-level application of rational peptide vaccine design, which may be a general paradigm for future viral vaccine development.

  8. Injectable polymer microspheres enhance immunogenicity of a contraceptive peptide vaccine.

    Science.gov (United States)

    Cui, Chengji; Stevens, Vernon C; Schwendeman, Steven P

    2007-01-01

    Advanced contraceptive peptide vaccines suffer from the unavailability of adjuvants capable of enhancing the antibody response with acceptable safety. We sought to overcome this limitation by employing two novel poly(lactic-co-glycolic acid) (PLGA) microsphere formulations to deliver a synthetic human chorionic gonadotropin (hCG) peptide antigen co-synthesized with a T-cell epitope from tetanus toxoid (TT), C-TT2-CTP35: surface-conjugated immunogen to induce phagocytosis; and encapsulated peptide to provide a depot effect, with MgCO(3) co-encapsulated in the polymer to neutralize acidity from the biodegrading PLGA polyester. A single immunization of encapsulated peptide in rabbits elicited a stronger antibody response with equivalent duration relative to a positive control--three injections of the peptide administered in a squalene-based water-in-oil emulsion. Surface-conjugated peptide was less effective but enhanced antibody levels at 1/5 the dose, relative to soluble antigen. Most remarkable and unexpected was the finding that co-encapsulation of base was essential to attain the powerful adjuvant effect of the PLGA-MgCO(3) system, as the MgCO(3)-free microspheres were completely ineffective. A promising contraceptive hCG peptide vaccine with acceptable side effects (i.e., local tissue reactions) was achieved by minimizing PLGA and MgCO(3) doses, without significantly affecting antibody response. PMID:16996662

  9. INVESTIGATION OF INDUCING EFFECT OF SPECIFIC CYTOTOXICITY OF CTLS BY ANTIGEN PEPTIDES FROM T LYMPHOCYTIC LEUKEMIA CELLS

    Institute of Scientific and Technical Information of China (English)

    张桂梅; 黄波; 李东; 王洪涛; 冯作化

    2003-01-01

    Objective: To investigate the characteristics of specific antitumor immunity induced by antigen peptides mixture from T lymphocytic leukemia cells. Method: Antigen peptides mixtures were prepared from different leukemia cell lines and then bound with Hsp70 in vitro. Human peripheral blood mononuclear cells (PBMC) were cultured in vitro, and activated with Hsp70-antigen peptides. The activated PBMC was cultured continuously in vitro, and used as effector cells in vitro test of cytotoxicity to different target cells. Results: The antigen peptides from different leukemia cell lines were peptides mixture and could activate PBMC effectively if they were presented by Hsp70. The activated PBMC could proliferate in the presence of IL-2 and Hsp70-antigen peptides. The proliferative PBMC had specific cytotoxicity to leukemia cells corresponding to the antigen peptides. PBMC activated by antigen peptides from T lymphocytic leukemia cell lines could effectively kill T lymphocytic leukemia cells, and the cytotoxicity of these PBMC to T lymphocytic leukemia cells was significantly stronger than that of PBMC activated by antigen peptides from other leukemia cells (P < 0.05). PBMC activated by either Hut78-peptides or Molt 4-peptides could effectively kill Jurkat cells. And the cytotoxicity of PBMC activated by Hut78/Molt-4-peptides to Jurkat cells was significantly stronger than that of PBMC activated by either Hut78-peptides or Molt-4-peptides alone (P<0.05).Conclusion: Antigen peptides mixture from T lymphocytic leukemia cell lines can induce specific cytotoxic effect to T lymphocytic leukemia cells. There exists cross-reactivity among antigen peptides mixture from different T lymphocytic leukemia cell lines. The cross-reactivity could be amplified by blending of different antigen peptides from different T lymphocytic leukemia cell lines, suggesting that it is possible to prepare broad-spectrum antigen peptide vaccine against T lymphocytic leukemia by using multiple leukemia

  10. Liposome-Based Adjuvants for Subunit Vaccines: Formulation Strategies for Subunit Antigens and Immunostimulators

    Directory of Open Access Journals (Sweden)

    Signe Tandrup Schmidt

    2016-03-01

    Full Text Available The development of subunit vaccines has become very attractive in recent years due to their superior safety profiles as compared to traditional vaccines based on live attenuated or whole inactivated pathogens, and there is an unmet medical need for improved vaccines and vaccines against pathogens for which no effective vaccines exist. The subunit vaccine technology exploits pathogen subunits as antigens, e.g., recombinant proteins or synthetic peptides, allowing for highly specific immune responses against the pathogens. However, such antigens are usually not sufficiently immunogenic to induce protective immunity, and they are often combined with adjuvants to ensure robust immune responses. Adjuvants are capable of enhancing and/or modulating immune responses by exposing antigens to antigen-presenting cells (APCs concomitantly with conferring immune activation signals. Few adjuvant systems have been licensed for use in human vaccines, and they mainly stimulate humoral immunity. Thus, there is an unmet demand for the development of safe and efficient adjuvant systems that can also stimulate cell-mediated immunity (CMI. Adjuvants constitute a heterogeneous group of compounds, which can broadly be classified into delivery systems or immunostimulators. Liposomes are versatile delivery systems for antigens, and they can carefully be customized towards desired immune profiles by combining them with immunostimulators and optimizing their composition, physicochemical properties and antigen-loading mode. Immunostimulators represent highly diverse classes of molecules, e.g., lipids, nucleic acids, proteins and peptides, and they are ligands for pattern-recognition receptors (PRRs, which are differentially expressed on APC subsets. Different formulation strategies might thus be required for incorporation of immunostimulators and antigens, respectively, into liposomes, and the choice of immunostimulator should ideally be based on knowledge regarding the

  11. Clearance of depot vaccine SPIO-labeled antigen and substrate visualized using MRI.

    Science.gov (United States)

    Brewer, Kimberly D; Lake, Kerry; Pelot, Nicole; Stanford, Marianne M; DeBay, Drew R; Penwell, Andrea; Weir, Genevieve M; Karkada, Mohan; Mansour, Marc; Bowen, Chris V

    2014-12-01

    Immunotherapies, including peptide-based vaccines, are a growing area of cancer research, and understanding their mechanism of action is crucial for their continued development and clinical application. Exploring the biodistribution of vaccine components may be key to understanding this action. This work used magnetic resonance imaging (MRI) to characterize the in vivo biodistribution of the antigen and oil substrate of the vaccine delivery system known as DepoVax(TM). DepoVax uses a novel adjuvanted lipid-in-oil based formulation to solubilise antigens and promote a depot effect. In this study, antigen or oil were tagged with superparamagnetic iron oxide (SPIO), making them visible on MR images. This enables tracking of individual vaccine components to determine changes in biodistribution. Mice were injected with SPIO-labeled antigen or SPIO-labeled oil, and imaged to examine clearance of labeled components from the vaccine site. The SPIO-antigen was steadily cleared, with nearly half cleared within two months post-vaccination. In contrast, the SPIO-oil remained relatively unchanged. The biodistribution of the SPIO-antigen component within the vaccine site was heterogeneous, indicating the presence of active clearance mechanisms, rather than passive diffusion or drainage. Mice injected with SPIO-antigen also showed MRI contrast for several weeks post-vaccination in the draining inguinal lymph node. These results indicate that MRI can visualize the in vivo longitudinal biodistribution of vaccine components. The sustained clearance is consistent with antigen up-take and trafficking by immune cells, leading to accumulation in the draining lymph node, which corresponds to the sustained immune responses and reduced tumor burden observed in vaccinated mice. PMID:25444822

  12. Liposome-Based Adjuvants for Subunit Vaccines: Formulation Strategies for Subunit Antigens and Immunostimulators

    DEFF Research Database (Denmark)

    Schmidt, Signe Tandrup; Foged, Camilla; Korsholm, Karen Smith;

    2016-01-01

    be classified into delivery systems or immunostimulators. Liposomes are versatile delivery systems for antigens, and they can carefully be customized towards desired immune profiles by combining them with immunostimulators and optimizing their composition, physicochemical properties and antigen-loading mode...... for which no effective vaccines exist. The subunit vaccine technology exploits pathogen subunits as antigens, e.g., recombinant proteins or synthetic peptides, allowing for highly specific immune responses against the pathogens. However, such antigens are usually not sufficiently immunogenic to induce...... protective immunity, and they are often combined with adjuvants to ensure robust immune responses. Adjuvants are capable of enhancing and/or modulating immune responses by exposing antigens to antigen-presenting cells (APCs) concomitantly with conferring immune activation signals. Few adjuvant systems have...

  13. A phase I study of vaccination with NY-ESO-1f peptide mixed with Picibanil OK-432 and Montanide ISA-51 in patients with cancers expressing the NY-ESO-1 antigen.

    Science.gov (United States)

    Kakimi, Kazuhiro; Isobe, Midori; Uenaka, Akiko; Wada, Hisashi; Sato, Eiichi; Doki, Yuichiro; Nakajima, Jun; Seto, Yasuyuki; Yamatsuji, Tomoki; Naomoto, Yoshio; Shiraishi, Kenshiro; Takigawa, Nagio; Kiura, Katsuyuki; Tsuji, Kazuhide; Iwatsuki, Keiji; Oka, Mikio; Pan, Linda; Hoffman, Eric W; Old, Lloyd J; Nakayama, Eiichi

    2011-12-15

    We conducted a phase I clinical trial of a cancer vaccine using a 20-mer NY-ESO-1f peptide (NY-ESO-1 91-110) that includes multiple epitopes recognized by antibodies, and CD4 and CD8 T cells. Ten patients were immunized with 600 μg of NY-ESO-1f peptide mixed with 0.2 KE Picibanil OK-432 and 1.25 ml Montanide ISA-51. Primary end points of the study were safety and immune response. Subcutaneous injection of the NY-ESO-1f peptide vaccine was well tolerated. Vaccine-related adverse events observed were fever (Grade 1), injection-site reaction (Grade 1 or 2) and induration (Grade 2). Vaccination with the NY-ESO-1f peptide resulted in an increase or induction of NY-ESO-1 antibody responses in nine of ten patients. The sera reacted with recombinant NY-ESO-1 whole protein as well as the NY-ESO-1f peptide. An increase in CD4 and CD8 T cell responses was observed in nine of ten patients. Vaccine-induced CD4 and CD8 T cells responded to NY-ESO-1 91-108 in all patients with various HLA types with a less frequent response to neighboring peptides. The findings indicate that the 20-mer NY-ESO-1f peptide includes multiple epitopes recognized by CD4 and CD8 T cells with distinct specificity. Of ten patients, two with lung cancer and one with esophageal cancer showed stable disease. Our study shows that the NY-ESO-1f peptide vaccine was well tolerated and elicited humoral, CD4 and CD8 T cell responses in immunized patients.

  14. Complex Minigene Library Vaccination for Discovery of Pre-Erythrocytic Plasmodium T Cell Antigens

    Science.gov (United States)

    Stone, Brad C.; Kas, Arnold; Billman, Zachary P.; Fuller, Deborah H.; Fuller, James T.; Shendure, Jay; Murphy, Sean C.

    2016-01-01

    Development of a subunit vaccine targeting liver-stage Plasmodium parasites requires the identification of antigens capable of inducing protective T cell responses. However, traditional methods of antigen identification are incapable of evaluating T cell responses against large numbers of proteins expressed by these parasites. This bottleneck has limited development of subunit vaccines against Plasmodium and other complex intracellular pathogens. To address this bottleneck, we are developing a synthetic minigene technology for multi-antigen DNA vaccines. In an initial test of this approach, pools of long (150 bp) antigen-encoding oligonucleotides were synthesized and recombined into vectors by ligation-independent cloning to produce two DNA minigene library vaccines. Each vaccine encoded peptides derived from 36 (vaccine 1) and 53 (vaccine 2) secreted or transmembrane pre-erythrocytic P. yoelii proteins. BALB/cj mice were vaccinated three times with a single vaccine by biolistic particle delivery (gene gun) and screened for interferon-γ-producing T cell responses by ELISPOT. Library vaccination induced responses against four novel antigens. Naïve mice exposed to radiation-attenuated sporozoites mounted a response against only one of the four novel targets (PyMDH, malate dehydrogenase). The response to PyMDH could not be recalled by additional homologous sporozoite immunizations but could be partially recalled by heterologous cross-species sporozoite exposure. Vaccination against the dominant PyMDH epitope by DNA priming and recombinant Listeria boosting did not protect against sporozoite challenge. Improvements in library design and delivery, combined with methods promoting an increase in screening sensitivity, may enable complex minigene screening to serve as a high-throughput system for discovery of novel T cell antigens. PMID:27070430

  15. Improving therapeutic HPV peptide-based vaccine potency by enhancing CD4+ T help and dendritic cell activation

    Directory of Open Access Journals (Sweden)

    Hung Chien-Fu

    2010-11-01

    Full Text Available Abstract Background Effective vaccination against human papillomavirus (HPV represents an opportunity to control cervical cancer. Peptide-based vaccines targeting HPV E6 and/or E7 antigens while safe, will most likely require additional strategies to enhance the vaccine potency. Methods We tested the HPV-16 E7 peptide-based vaccine in combination with a strategy to enhance CD4+ T help using a Pan HLA-DR epitope (PADRE peptide and a strategy to enhance dendritic cell activation using the toll-like receptor 3 ligand, poly(I:C. Results We observed that mice vaccinated with E7 peptide-based vaccine in combination with PADRE peptide and poly(I:C generated better E7-specific CD8+ T cell immune responses as well as significantly improved therapeutic anti-tumor effects against TC-1 tumors compared to E7 peptide-based vaccine with either PADRE peptide or poly(I:C alone. Furthermore, we found that intratumoral vaccination with the E7 peptide in conjunction with PADRE peptide and poly(I:C generates a significantly higher frequency of E7-specific CD8+ T cells as well as better survival compared to subcutaneous vaccination with the same regimen in treated mice. Conclusions The combination of PADRE peptide and poly(I:C with antigenic peptide is capable of generating potent antigen-specific CD8+ T cell immune responses and antitumor effects in vaccinated mice. Our study has significant clinical implications for peptide-based vaccination.

  16. Identification of protective antigens for vaccination against systemic salmonellosis

    Directory of Open Access Journals (Sweden)

    Dirk eBumann

    2014-08-01

    Full Text Available There is an urgent medical need for improved vaccines with broad serovar coverage and high efficacy against systemic salmonellosis. Subunit vaccines offer excellent safety profiles but require identification of protective antigens, which remains a challenging task. Here, I review crucial properties of Salmonella antigens that might help to narrow down the number of potential candidates from more than 4000 proteins encoded in Salmonella genomes, to a more manageable number of 50-200 most promising antigens. I also discuss complementary approaches for antigen identification and potential limitations of current pre-clinical vaccine testing.

  17. A Review of Pneumococcal Vaccines: Current Polysaccharide Vaccine Recommendations and Future Protein Antigens

    OpenAIRE

    Daniels, Calvin C.; Rogers, P. David; Shelton, Chasity M.

    2016-01-01

    This review describes development of currently available pneumococcal vaccines, provides summary tables of current pneumococcal vaccine recommendations in children and adults, and describes new potential vaccine antigens in the pipeline. Streptococcus pneumoniae, the bacteria responsible for pneumonia, otitis media, meningitis and bacteremia, remains a cause of morbidity and mortality in both children and adults. Introductions of unconjugated and conjugated pneumococcal polysaccharide vaccine...

  18. Evaluation of MAP-specific peptides following vaccination of goats

    DEFF Research Database (Denmark)

    Lybeck, Kari; Sjurseth, Siri K.; Melvang, Heidi Mikkelsen;

    Our aim is to develop a subunit MAP vaccine not interfering with the diagnosis of paratuberculosis or bovine tuberculosis. This study’s objective was to evaluate MAP-specific peptides defined by in silico analysis. Peptides were picked by 1) comparing MAP genomes to that of other mycobacterium...... species or 2) selected based on “experience”. Peptides predicted to bind bovine MHC II by in silico analysis were included in further studies, resulting in two panels 1) genome-based and 2) selected. Initially, two groups of 15 healthy goats were vaccinated with one of the two panels (50 µg/peptide in CAF......01 adjuvant/CAF04 for boosting). Four MAP-infected goats were also vaccinated. In a second vaccination trail, groups of 8 healthy goat kids were vaccinated with genome-based peptides, selected peptides or selected peptides linked together in a recombinant protein (20 µg/peptide or 50 µg protein...

  19. Use of antigenic cartography in vaccine seed strain selection.

    Science.gov (United States)

    Fouchier, Ron A M; Smith, Derek J

    2010-03-01

    Human influenza A viruses are classic examples of antigenically variable pathogens that have a seemingly endless capacity to evade the host's immune response. The viral hemagglutinin (HA) and neuraminidase (NA) proteins are the main targets of our antibody response to combat infections. HA and NA continuously change to escape from humoral immunity, a process known as antigenic drift. As a result of antigenic drift, the human influenza vaccine is updated frequently. The World Health Organization (WHO) coordinates a global influenza surveillance network that, by the hemagglutination inhibition (HI) assay, routinely characterizes the antigenic properties of circulating strains in order to select new seed viruses for such vaccine updates. To facilitate a quantitative interpretation and easy visualization of HI data, a new computational technique called "antigenic cartography" was developed. Since its development, antigenic cartography has been applied routinely to assist the WHO with influenza surveillance activities. Until recently, antigenic variation was not considered a serious issue with influenza vaccines for poultry. However, because of the diversification of the Asian H5N1 lineage since 1996 into multiple genetic clades and subclades, and because of the long-term use of poultry vaccines against H5 in some parts of the world, this issue needs to be re-addressed. The antigenic properties of panels of avian H5N1 viruses were characterized by HI assay, using mammalian or avian antisera, and analyzed using antigenic cartography methods. These analyses revealed antigenic differences between circulating H5N1 viruses and the H5 viruses used in poultry vaccines. Considerable antigenic variation was also observed within and between H5N1 clades. These observations have important implications for the efficacy and long-term use of poultry vaccines.

  20. Overlapping Synthetic Peptides Encoding TPD52 as Breast Cancer Vaccine in Mice: Prolonged Survival1

    OpenAIRE

    Mirshahidi, Saied; Kramer, Victor G; James B Whitney; Essono, Sosthène; Lee, Sandra; Dranoff, Glenn; Anderson, Karen S.; Ruth M Ruprecht

    2009-01-01

    Peptide-based vaccines, one of several anti-tumor immunization strategies currently under investigation, can elicit both MHC Class I-restricted (CD8+) and Class II-restricted (CD4+) responses. However, the need to identify specific T-cell epitopes in the context of MHC alleles has hampered the application of this approach. We have tested overlapping synthetic peptides (OSP) representing a tumor antigen as a novel approach that bypasses the need for epitope mapping, since OSP contain all possi...

  1. Long-Term Follow-Up of HLA-A2+ Patients with High-Risk, Hormone-Sensitive Prostate Cancer Vaccinated with the Prostate Specific Antigen Peptide Homologue (PSA146-154)

    OpenAIRE

    Perambakam, Supriya; Xie, Hui; Edassery, Seby; Peace, David J.

    2011-01-01

    Twenty-eight HLA-A2+ patients with high-risk, locally advanced or metastatic, hormone-sensitive prostate cancer were immunized with a peptide homologue of prostate-specific antigen, PSA146-154, between July 2002 and September 2004 and monitored for clinical and immune responses. Fifty percent of the patients developed strong PSA146-154-peptide-specific delayed-type hypersensitivity skin responses, tetramer and/or IFN-γ responses within one year. Thirteen patients had stable or declining serum...

  2. Long-Term Follow-Up of HLA-A2+ Patients with High-Risk, Hormone-Sensitive Prostate Cancer Vaccinated with the Prostate Specific Antigen Peptide Homologue (PSA146-154)

    OpenAIRE

    Perambakam, Supriya; Xie, Hui; Edassery, Seby; Peace, David J.

    2010-01-01

    Twenty-eight HLA-A2+ patients with high-risk, locally advanced or metastatic, hormone-sensitive prostate cancer were immunized with a peptide homologue of prostate-specific antigen, PSA146-154, between July 2002 and September 2004 and monitored for clinical and immune responses. Fifty percent of the patients developed strong PSA146-154-peptide-specific delayed-type hypersensitivity skin responses, tetramer and/or IFN-γ responses within one year. Thirteen patients had stable or declining serum...

  3. A combined approach of human leukocyte antigen ligandomics and immunogenicity analysis to improve peptide-based cancer immunotherapy.

    Science.gov (United States)

    Peper, Janet Kerstin; Stevanović, Stefan

    2015-10-01

    The breakthrough development of immune checkpoint inhibitors as clinically effective novel therapies demonstrates the potential of cancer immunotherapy. The identification of suitable targets for specific immunotherapy, however, remains a challenging task. Most peptides previously used for vaccination in clinical trials were able to elicit strong immunological responses but failed with regard to clinical benefit. This might, at least partly, be caused by an inadequate peptide selection, usually derived from established tumor-associated antigens which are not necessarily presented as human leukocyte antigen (HLA) ligands. Recently, HLA ligandome analysis revealed cancer-associated peptides, which have been used in clinical trials showing encouraging impact on survival. To improve peptide-based cancer immunotherapy, our group established a combined approach of HLA ligandomics and immunogenicity analysis for the identification of vaccine peptides. This approach is based on the identification of naturally presented HLA ligands on tumor samples, the selection of tumor-associated/tumor-specific HLA ligands and their subsequent testing for immunogenicity in vitro. In this review, we want to present our pipeline for the identification of vaccine peptides, focusing on ovarian cancer, and want to discuss differences to other approaches. Furthermore, we want to give a short outlook of a potential multi-peptide vaccination trial using the novel identified peptides.

  4. WT1 vaccination in AML and MDS: A pilot trial with synthetic analog peptides.

    Science.gov (United States)

    Brayer, Jason; Lancet, Jeffrey E; Powers, John; List, Alan; Balducci, Lodovico; Komrokji, Rami; Pinilla-Ibarz, Javier

    2015-07-01

    Peptide vaccines are capable of eliciting immune responses targeting tumor-associated antigens such as the Wilms' Tumor 1 (WT1) antigen, often overexpressed in myeloid malignancies. Here, we assessed the safety, tolerability, and immunogenicity of a polyvalent WT1 peptide vaccine. Individuals with WT1-positive acute myeloid leukemia (AML) in first (CR1) or second (CR2) remission or with higher-risk myelodysplastic syndrome (MDS) following at least 1 prior line of therapy were vaccinated with a mixture of peptides derived from the WT1 protein, with sargramostim injections before vaccination to amplify immunogenicity. Six vaccinations were delivered biweekly, continuing then monthly until patients received 12 vaccinations or showed disease relapse or progression. Therapeutic efficacy was evaluated by progression-free and overall survival. Immune responses were evaluated by delayed-type hypersensitivity testing and T-cell IFNγ ELISPOT at specified intervals. In 16 patients who received at least one vaccination, 10 completed the planned course of six vaccinations and six continued for up to six additional monthly vaccinations. Vaccinations were well tolerated, with no patients discontinuing due to toxicity. One of two patients with high-risk MDS experienced a prolonged decrease in transfusion dependence. Two of 14 AML patients demonstrated relapse-free survival >1 year. Both patients were in CR2 at time of vaccination, with duration of their remission exceeding duration of their first remission, suggesting a potential benefit. Our WT1 vaccine was well-tolerated. The clinical benefit that we observed in several patients suggests engagement of a protective immune response, indicating a need for further trials. PMID:25802083

  5. Synthetic Long Peptide Derived from Mycobacterium tuberculosis Latency Antigen Rv1733c Protects against Tuberculosis.

    Science.gov (United States)

    Coppola, Mariateresa; van den Eeden, Susan J F; Wilson, Louis; Franken, Kees L M C; Ottenhoff, Tom H M; Geluk, Annemieke

    2015-09-01

    Responsible for 9 million new cases of active disease and nearly 2 million deaths each year, tuberculosis (TB) remains a global health threat of overwhelming dimensions. Mycobacterium bovis BCG, the only licensed vaccine available, fails to confer lifelong protection and to prevent reactivation of latent infection. Although 15 new vaccine candidates are now in clinical trials, an effective vaccine against TB remains elusive, and new strategies for vaccination are vital. BCG vaccination fails to induce immunity against Mycobacterium tuberculosis latency antigens. Synthetic long peptides (SLPs) combined with adjuvants have been studied mostly for therapeutic cancer vaccines, yet not for TB, and proved to induce efficient antitumor immunity. This study investigated an SLP derived from Rv1733c, a major M. tuberculosis latency antigen which is highly expressed by "dormant" M. tuberculosis and well recognized by T cells from latently M. tuberculosis-infected individuals. In order to assess its in vivo immunogenicity and protective capacity, Rv1733c SLP in CpG was administered to HLA-DR3 transgenic mice. Immunization with Rv1733c SLP elicited gamma interferon-positive/tumor necrosis factor-positive (IFN-γ(+)/TNF(+)) and IFN-γ(+) CD4(+) T cells and Rv1733c-specific antibodies and led to a significant reduction in the bacterial load in the lungs of M. tuberculosis-challenged mice. This was observed both in a pre- and in a post-M. tuberculosis challenge setting. Moreover, Rv1733c SLP immunization significantly boosted the protective efficacy of BCG, demonstrating the potential of M. tuberculosis latency antigens to improve BCG efficacy. These data suggest a promising role for M. tuberculosis latency antigen Rv1733c-derived SLPs as a novel TB vaccine approach, both in a prophylactic and in a postinfection setting.

  6. Pentamers not found in the universal proteome can enhance antigen specific immune responses and adjuvant vaccines.

    Science.gov (United States)

    Patel, Ami; Dong, Jessica C; Trost, Brett; Richardson, Jason S; Tohme, Sarah; Babiuk, Shawn; Kusalik, Anthony; Kung, Sam K P; Kobinger, Gary P

    2012-01-01

    Certain short peptides do not occur in humans and are rare or non-existent in the universal proteome. Antigens that contain rare amino acid sequences are in general highly immunogenic and may activate different arms of the immune system. We first generated a list of rare, semi-common, and common 5-mer peptides using bioinformatics tools to analyze the UniProtKB database. Experimental observations indicated that rare and semi-common 5-mers generated stronger cellular responses in comparison with common-occurring sequences. We hypothesized that the biological process responsible for this enhanced immunogenicity could be used to positively modulate immune responses with potential application for vaccine development. Initially, twelve rare 5-mers, 9-mers, and 13-mers were incorporated in frame at the end of an H5N1 hemagglutinin (HA) antigen and expressed from a DNA vaccine. The presence of some 5-mer peptides induced improved immune responses. Adding one 5-mer peptide exogenously also offered improved clinical outcome and/or survival against a lethal H5N1 or H1N1 influenza virus challenge in BALB/c mice and ferrets, respectively. Interestingly, enhanced anti-HBsAg antibody production by up to 25-fold in combination with a commercial Hepatitis B vaccine (Engerix-B, GSK) was also observed in BALB/c mice. Mechanistically, NK cell activation and dependency was observed with enhancing peptides ex vivo and in NK-depleted mice. Overall, the data suggest that rare or non-existent oligopeptides can be developed as immunomodulators and supports the further evaluation of some 5-mer peptides as potential vaccine adjuvants. PMID:22937099

  7. Pentamers not found in the universal proteome can enhance antigen specific immune responses and adjuvant vaccines.

    Directory of Open Access Journals (Sweden)

    Ami Patel

    Full Text Available Certain short peptides do not occur in humans and are rare or non-existent in the universal proteome. Antigens that contain rare amino acid sequences are in general highly immunogenic and may activate different arms of the immune system. We first generated a list of rare, semi-common, and common 5-mer peptides using bioinformatics tools to analyze the UniProtKB database. Experimental observations indicated that rare and semi-common 5-mers generated stronger cellular responses in comparison with common-occurring sequences. We hypothesized that the biological process responsible for this enhanced immunogenicity could be used to positively modulate immune responses with potential application for vaccine development. Initially, twelve rare 5-mers, 9-mers, and 13-mers were incorporated in frame at the end of an H5N1 hemagglutinin (HA antigen and expressed from a DNA vaccine. The presence of some 5-mer peptides induced improved immune responses. Adding one 5-mer peptide exogenously also offered improved clinical outcome and/or survival against a lethal H5N1 or H1N1 influenza virus challenge in BALB/c mice and ferrets, respectively. Interestingly, enhanced anti-HBsAg antibody production by up to 25-fold in combination with a commercial Hepatitis B vaccine (Engerix-B, GSK was also observed in BALB/c mice. Mechanistically, NK cell activation and dependency was observed with enhancing peptides ex vivo and in NK-depleted mice. Overall, the data suggest that rare or non-existent oligopeptides can be developed as immunomodulators and supports the further evaluation of some 5-mer peptides as potential vaccine adjuvants.

  8. New Data on Vaccine Antigen Deficient Bordetella pertussis Isolates

    Directory of Open Access Journals (Sweden)

    Valérie Bouchez

    2015-09-01

    Full Text Available Evolution of Bordetella pertussis is driven by natural and vaccine pressures. Isolates circulating in regions with high vaccination coverage present multiple allelic and antigenic variations as compared to isolates collected before introduction of vaccination. Furthermore, during the last epidemics reported in regions using pertussis acellular vaccines, isolates deficient for vaccine antigens, such as pertactin (PRN, were reported to reach high proportions of circulating isolates. More sporadic filamentous hemagglutinin (FHA or pertussis toxin (PT deficient isolates were also collected. The whole genome of some recent French isolates, deficient or non-deficient in vaccine antigens, were analyzed. Transcription profiles of the expression of the main virulence factors were also compared. The invasive phenotype in an in vitro human tracheal epithelial (HTE cell model of infection was evaluated. Our genomic analysis focused on SNPs related to virulence genes known to be more likely to present allelic polymorphism. Transcriptomic data indicated that isolates circulating since the introduction of pertussis vaccines present lower transcription levels of the main virulence genes than the isolates of the pre-vaccine era. Furthermore, isolates not producing FHA present significantly higher expression levels of the entire set of genes tested. Finally, we observed that recent isolates are more invasive in HTE cells when compared to the reference strain, but no multiplication occurs within cells.

  9. Discovery of Novel Plasmodium falciparum Pre-Erythrocytic Antigens for Vaccine Development.

    Directory of Open Access Journals (Sweden)

    Joao C Aguiar

    Full Text Available Nearly 100% protection against malaria infection can be achieved in humans by immunization with P. falciparum radiation-attenuated sporozoites (RAS. Although it is thought that protection is mediated by T cell and antibody responses, only a few of the many pre-erythrocytic (sporozoite and liver stage antigens that are targeted by these responses have been identified.Twenty seven P. falciparum pre-erythrocytic antigens were selected using bioinformatics analysis and expression databases and were expressed in a wheat germ cell-free protein expression system. Recombinant proteins were recognized by plasma from RAS-immunized subjects, and 21 induced detectable antibody responses in mice and rabbit and sera from these immunized animals were used to characterize these antigens. All 21 proteins localized to the sporozoite: five localized to the surface, seven localized to the micronemes, cytoplasm, endoplasmic reticulum or nucleus, two localized to the surface and cytoplasm, and seven remain undetermined. PBMC from RAS-immunized volunteers elicited positive ex vivo or cultured ELISpot responses against peptides from 20 of the 21 antigens.These T cell and antibody responses support our approach of using reagents from RAS-immunized subjects to screen potential vaccine antigens, and have led to the identification of a panel of novel P. falciparum antigens. These results provide evidence to further evaluate these antigens as vaccine candidates.ClinicalTrials.gov NCT00870987 ClinicalTrials.gov NCT00392015.

  10. Discovery of Novel Plasmodium falciparum Pre-Erythrocytic Antigens for Vaccine Development

    Science.gov (United States)

    Aguiar, Joao C.; Bolton, Jessica; Wanga, Joyce; Sacci, John B.; Iriko, Hideyuki; Mazeika, Julie K.; Han, Eun-Taek; Limbach, Keith; Patterson, Noelle B.; Sedegah, Martha; Cruz, Ann-Marie; Tsuboi, Takafumi; Hoffman, Stephen L.; Carucci, Daniel; Hollingdale, Michael R.; Villasante, Eileen D.; Richie, Thomas L.

    2015-01-01

    Background Nearly 100% protection against malaria infection can be achieved in humans by immunization with P. falciparum radiation-attenuated sporozoites (RAS). Although it is thought that protection is mediated by T cell and antibody responses, only a few of the many pre-erythrocytic (sporozoite and liver stage) antigens that are targeted by these responses have been identified. Methodology Twenty seven P. falciparum pre-erythrocytic antigens were selected using bioinformatics analysis and expression databases and were expressed in a wheat germ cell-free protein expression system. Recombinant proteins were recognized by plasma from RAS-immunized subjects, and 21 induced detectable antibody responses in mice and rabbit and sera from these immunized animals were used to characterize these antigens. All 21 proteins localized to the sporozoite: five localized to the surface, seven localized to the micronemes, cytoplasm, endoplasmic reticulum or nucleus, two localized to the surface and cytoplasm, and seven remain undetermined. PBMC from RAS-immunized volunteers elicited positive ex vivo or cultured ELISpot responses against peptides from 20 of the 21 antigens. Conclusions These T cell and antibody responses support our approach of using reagents from RAS-immunized subjects to screen potential vaccine antigens, and have led to the identification of a panel of novel P. falciparum antigens. These results provide evidence to further evaluate these antigens as vaccine candidates. Trial Registration ClinicalTrials.gov NCT00870987 ClinicalTrials.gov NCT00392015 PMID:26292257

  11. Chitosan-Poly (I:C)-PADRE Based Nanoparticles as Delivery Vehicles for Synthetic Peptide Vaccines.

    Science.gov (United States)

    Correia-Pinto, Jorge F; Csaba, Noemi; Schiller, John T; Alonso, Maria J

    2015-01-01

    The safety and precision of peptide antigens has prompted the search for adjuvants capable of increasing the immune response against these intrinsically poorly immunogenic antigens. The integration of both immunostimulants and peptide antigens within nanometric delivery systems for their co-delivery to immune cells is a promising vaccination strategy. With this in mind, the potential synergistic effect of the immunostimulant poly (I:C) (pIC) and a T-Helper peptide (PADRE), integrated into a chitosan (CS) based nanostructure, was explored. The value of this nanostructured combination of materials was assessed for a peptide antigen (1338aa) derived from the HPV-16 L2 protein. These nanoparticles, produced by ionic gelation technique, exhibited a nanometric size (40 mV) and high pIC association efficiency (>96%). They also showed capacity for the association of both the 1338aa and PADRE peptides. The influence of the presence of pIC and PADRE in the nanocomposition, as well as that of the peptide presentation form (encapsulated versus surface adsorbed) on the antibody induction was evaluated in a preliminary in vivo study. The data obtained highlights the possibility to engineer nanoparticles through the rational combination of a number of adjuvant molecules together with the antigen.

  12. Chitosan-Poly (I:C-PADRE Based Nanoparticles as Delivery Vehicles for Synthetic Peptide Vaccines

    Directory of Open Access Journals (Sweden)

    Jorge F. Correia-Pinto

    2015-09-01

    Full Text Available The safety and precision of peptide antigens has prompted the search for adjuvants capable of increasing the immune response against these intrinsically poorly immunogenic antigens. The integration of both immunostimulants and peptide antigens within nanometric delivery systems for their co-delivery to immune cells is a promising vaccination strategy. With this in mind, the potential synergistic effect of the immunostimulant poly (I:C (pIC and a T-Helper peptide (PADRE, integrated into a chitosan (CS based nanostructure, was explored. The value of this nanostructured combination of materials was assessed for a peptide antigen (1338aa derived from the HPV-16 L2 protein. These nanoparticles, produced by ionic gelation technique, exhibited a nanometric size (<300 nm, a high positive surface charge (>40 mV and high pIC association efficiency (>96%. They also showed capacity for the association of both the 1338aa and PADRE peptides. The influence of the presence of pIC and PADRE in the nanocomposition, as well as that of the peptide presentation form (encapsulated versus surface adsorbed on the antibody induction was evaluated in a preliminary in vivo study. The data obtained highlights the possibility to engineer nanoparticles through the rational combination of a number of adjuvant molecules together with the antigen.

  13. Vaccine delivery by penetratin: mechanism of antigen presentation by dendritic cells.

    Science.gov (United States)

    Pouniotis, Dodie; Tang, Choon-Kit; Apostolopoulos, Vasso; Pietersz, Geoffrey

    2016-08-01

    Cell-penetrating peptides (CPP) or membrane-translocating peptides such as penetratin from Antennapedia homeodomain or TAT from human immunodeficiency virus are useful vectors for the delivery of protein antigens or their cytotoxic (Tc) or helper (Th) T cell epitopes to antigen-presenting cells. Mice immunized with CPP containing immunogens elicit antigen-specific Tc and/or Th responses and could be protected from tumor challenges. In the present paper, we investigate the mechanism of class I and class II antigen presentation of ovalbumin covalently linked to penetratin (AntpOVA) by bone marrow-derived dendritic cells with the use of biochemical inhibitors of various pathways of antigen processing and presentation. Results from our study suggested that uptake of AntpOVA is via a combination of energy-independent (membrane fusion) and energy-dependent pathways (endocytosis). Once internalized by either mechanism, multiple tap-dependent or independent antigen presentation pathways are accessed while not completely dependent on proteasomal processing but involving proteolytic trimming in the ER and Golgi compartments. Our study provides an understanding on the mechanism of antigen presentation mediated by CPP and leads to greater insights into future development of vaccine formulations. PMID:27138940

  14. Cancer-germline antigen vaccines and epigenetic enhancers

    DEFF Research Database (Denmark)

    Gjerstorff, Morten Frier; Burns, Jorge; Ditzel, Henrik Jorn

    2010-01-01

    can be achieved using epigenetic modifiers. AREAS COVERED IN THIS REVIEW: We provide an overview of the potential of CG antigens as targets for cancer immunotherapy, including advantages and disadvantages. We also discuss the current state of development of CG antigen vaccines, and the potential...... synergistic effect of combining CG antigen immunotherapeutic strategies with epigenetic modifiers. WHAT THE READER WILL GAIN: The reader will gain an overview of the past, present and future role of CG antigens in cancer immunotherapy. TAKE HOME MESSAGE: Chemoimmunotherapy using epigenetic drugs and CG...

  15. Molecular characterization of antigen-peptide pulsed dendritic cells: immature dendritic cells develop a distinct molecular profile when pulsed with antigen peptide.

    Directory of Open Access Journals (Sweden)

    Amy X Yang

    Full Text Available As dendritic cells (DCs are the most potent professional antigen-presenting cells, they are being tested as cancer vaccines for immunotherapy of established cancers. Although numerous studies have characterized DCs by their phenotype and function, few have identified potential molecular markers of antigen presentation prior to vaccination of host. In this study we generated pre-immature DC (piDC, immature DC (iDC, and mature DC (mDC from human peripheral blood monocytes (PBMC obtained from HLA-A2 healthy donors, and pulsed them with human papillomavirus E7 peptide (p11-20, a class I HLA-A2 binding antigen. We then characterized DCs for cell surface phenotype and gene expression profile by microarray technology. We identified a set of 59 genes that distinguished three differentiation stages of DCs (piDC, iDC and mDC. When piDC, iDC and mDC were pulsed with E7 peptide for 2 hrs, the surface phenotype did not change, however, iDCs rather than mDCs showed transcriptional response by up-regulation of a set of genes. A total of 52 genes were modulated in iDC upon antigen pulsing. Elongation of pulse time for iDCs to 10 and 24 hrs did not significantly bring further changes in gene expression. The E7 peptide up-modulated immune response (KPNA7, IGSF6, NCR3, TREM2, TUBAL3, IL8, NFKBIA, pro-apoptosis (BTG1, SEMA6A, IGFBP3 and SRGN, anti-apoptosis (NFKBIA, DNA repair (MRPS11, RAD21, TXNRD1, and cell adhesion and cell migration genes (EPHA1, PGF, IL8 and CYR61 in iDCs. We confirmed our results by Q-PCR analysis. The E7 peptide but not control peptide (PADRE induced up-regulation of NFKB1A gene only in HLA-A2 positive iDCs and not in HLA-A2 negative iDCs. These results suggest that E7 up-regulation of genes is specific and HLA restricted and that these genes may represent markers of antigen presentation and help rapidly assess the quality of dendritic cells prior to administration to the host.

  16. Three-day dendritic cells for vaccine development: Antigen uptake, processing and presentation

    Directory of Open Access Journals (Sweden)

    Schendel Dolores J

    2010-09-01

    Full Text Available Abstract Background Antigen-loaded dendritic cells (DC are capable of priming naïve T cells and therefore represent an attractive adjuvant for vaccine development in anti-tumor immunotherapy. Numerous protocols have been described to date using different maturation cocktails and time periods for the induction of mature DC (mDC in vitro. For clinical application, the use of mDC that can be generated in only three days saves on the costs of cytokines needed for large scale vaccine cell production and provides a method to produce cells within a standard work-week schedule in a GMP facility. Methods In this study, we addressed the properties of antigen uptake, processing and presentation by monocyte-derived DC prepared in three days (3d mDC compared with conventional DC prepared in seven days (7d mDC, which represent the most common form of DC used for vaccines to date. Results Although they showed a reduced capacity for spontaneous antigen uptake, 3d mDC displayed higher capacity for stimulation of T cells after loading with an extended synthetic peptide that requires processing for MHC binding, indicating they were more efficient at antigen processing than 7d DC. We found, however, that 3d DC were less efficient at expressing protein after introduction of in vitro transcribed (ivtRNA by electroporation, based on published procedures. This deficit was overcome by altering electroporation parameters, which led to improved protein expression and capacity for T cell stimulation using low amounts of ivtRNA. Conclusions This new procedure allows 3d mDC to replace 7d mDC for use in DC-based vaccines that utilize long peptides, proteins or ivtRNA as sources of specific antigen.

  17. Global inhibition of DC priming capacity in the spleen of self-antigen vaccinated mice requires IL-10

    Directory of Open Access Journals (Sweden)

    Douglas Matthew Marvel

    2014-02-01

    Full Text Available DC in the spleen are highly activated following intravenous vaccination with a foreign antigen, promoting expansion of effector T cells, but remain phenotypically and functionally immature after vaccination with a self-antigen. Up-regulation or suppression of expression of a cohort of pancreatic enzymes 24-72 hours post-vaccination can be used as a biomarker of stimulatory versus toleragenic DC, respectively. Here we show, using MUC1 transgenic mice (MUC1.Tg and a vaccine based on the MUC1 peptide which these mice perceive as a self-antigen, that the difference in enzyme expression that predicts whether DC will promote immune response or immune tolerance, is seen as early as 4-8 hours following vaccination. We also identify early production of IL-10 as a predominant factor that both correlates with this early time point and controls DC function. Pre-treating mice with an antibody against the IL-10 receptor (IL-10R prior to vaccination results in DC that up-regulate CD40, CD80, and CD86 and promote stronger IFNγ+ T cell responses. This study suggests that transient inhibition of IL-10 prior to vaccination could improve responses to cancer vaccines that utilize self-tumor antigens.

  18. IMMUNOLOGICAL CHARACTERISTIC OF SYNTHETIC PEPTIDES SIMILAR TO ACTUAL HIV ANTIGEN DETERMINANTS

    Directory of Open Access Journals (Sweden)

    S. V. Korobova

    2016-01-01

    Full Text Available The development of HIV vaccine remains an important goal in prophylaxis and therapy of HIV/ AIDS epidemics. There are various approaches for development of а candidate vaccine based on induction of neutralizing antibodies and cell-mediated immunity. Synthetic peptides are considered promising vaccine antigens since they are capable of activating both humoral and cellular immune response. HIV-1 envelope gp120 is the target for neutralizing antiviral antibodies. The V3 region of the HIV-1 gp120 is highly immunogenic and important for the virus-coreceptor interaction. In a RV144 vaccine trial, the levels of vaccine-induced IgG antibodies recognizing V1V2 regions from multiple HIV-1 subtypes show inverse correlations with a risk for HIV-1 infection. Meanwhile, HIV is characterized by high diversity. The consensus and mosaic immunogens are complete but artificial proteins, which are computationally designed to elicit immune responses with improved cross-reactive broadness. We have been studied immunogenic properties of synthetic peptides derived from V1, V2, V3 loop regions of the consensus M HIV1 (CON-S sequence group of the gp 120 envelope protein and V3 loop derived from a Russian RUA022a2 isolate. These peptides specifically reacted to HIV-positive sera in ELISA, thus indicating their similarity to appropriate HIV proteins. The peptides proved to be weakly immunogenic. Therefore, Freund complete adjuvant was used to enhance peptide immunogenicity. To assess the immunogenicity, the mice were immunized with a peptide mixture. Antibodies have been developed to every peptide from the mixture, being, predominantly, of IgG isotype. The antibody titers depended on the length of peptide sequences. However, the sera from immunized mice did not have a HIV neutralizing activity. The serum neutralization was assessed by pseudovirus-based assay, using a molecular clone of virus isolates CAP 45.2.00.G3 and QH.209.14.M.EnvA2. The virus neutralization is a

  19. Pre-Vaccination Frequencies of Th17 Cells Correlate with Vaccine-Induced T-Cell Responses to Survivin-Derived Peptide Epitopes

    DEFF Research Database (Denmark)

    Køllgaard, Tania Maria Simonsen; Ugurel-Becker, Selma; Idorn, Manja;

    2015-01-01

    as well as clinical outcome in metastatic melanoma patients vaccinated with survivin-derived peptides. Notably, we observed dysfunctional Th1 and cytotoxic T cells, i.e. down-regulation of the CD3ζchain (p=0.001) and an impaired IFNγ-production (p=0.001) in patients compared to healthy donors, suggesting......Various subsets of immune regulatory cells are suggested to influence the outcome of therapeutic antigen-specific anti-tumor vaccinations. We performed an exploratory analysis of a possible correlation of pre-vaccination Th17 cells, MDSCs, and Tregs with both vaccination-induced T-cell responses...

  20. Generation and Characterization of Human Monoclonal Antibodies Targeting Anthrax Protective Antigen following Vaccination with a Recombinant Protective Antigen Vaccine

    OpenAIRE

    Chi, Xiangyang; Li, Jianmin; Liu, Weicen; Wang, Xiaolin; Yin, Kexin; Liu, Ju; Zai, Xiaodong; Li, Liangliang; Song, Xiaohong; Zhang, Jun; Zhang, Xiaopeng; Yin, Ying; Fu, Ling; Xu, Junjie; Yu, Changming

    2015-01-01

    The anthrax protective antigen (PA) is the central component of the three-part anthrax toxin, and it is the primary immunogenic component in the approved AVA anthrax vaccine and the “next-generation” recombinant PA (rPA) anthrax vaccines. Animal models have indicated that PA-specific antibodies (AB) are sufficient to protect against infection with Bacillus anthracis. In this study, we investigated the PA domain specificity, affinity, mechanisms of neutralization, and synergistic effects of PA...

  1. A computational method for identification of vaccine targets from protein regions of conserved human leukocyte antigen binding

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn; Simon, Christian; Kudahl, Ulrich J.;

    2015-01-01

    variable regions, where all variants bind HLA. These regions, although variable, can thus be considered stable in terms of HLA binding and represent valuable vaccine targets. Results: We applied this method to predict CD8+ T-cell targets in influenza A H7N9 hemagglutinin and significantly increased......Background: Computational methods for T cell-based vaccine target discovery focus on selection of highly conserved peptides identified across pathogen variants, followed by prediction of their binding of human leukocyte antigen molecules. However, experimental studies have shown that T cells often...... target diverse regions in highly variable viral pathogens and this diversity may need to be addressed through redefinition of suitable peptide targets. Methods: We have developed a method for antigen assessment and target selection for polyvalent vaccines, with which we identified immune epitopes from...

  2. Targeting dendritic cells in lymph node with an antigen peptide-based nanovaccine for cancer immunotherapy.

    Science.gov (United States)

    Qian, Yuan; Jin, Honglin; Qiao, Sha; Dai, Yanfeng; Huang, Chuan; Lu, Lisen; Luo, Qingming; Zhang, Zhihong

    2016-08-01

    The design of peptide-based subunit vaccine formulations for the direct delivery of tumor antigen peptides (Aps) to dendritic cells (DCs) localized within draining lymph nodes (DLNs) is challenging. Mature DCs (mDCs) are abundantly distributed within DLNs but have dramatically reduced endocytic uptake and antigen-processing abilities, so their role as potential vaccine targets has been largely overlooked. Here we report an ultra-small biocompatible nanovaccine (α-Ap-FNP) functionalized by avidly targeting delivery of Ap via the scavenger receptor class B1 (SR-B1) pathway to mDCs. The self-assembly, small size (∼30 nm), SR-B1-targeting and optical properties of α-Ap-FNP resulted in its efficient Ap loading, substantial LN accumulation, targeting of mDCs and enhanced Ap presentation, and fluorescence trafficking, respectively. We also demonstrate that the α-Ap-FNP can be either used alone or encapsulated with CpG oligodeoxynucleotide as a prophylactic and therapeutic vaccine. Thus, the excellent properties of α-Ap-FNP provide it potential for clinical applications as a potent nanovaccine for cancer immunotherapy.

  3. Autologous peptides constitutively occupy the antigen binding site on Ia

    DEFF Research Database (Denmark)

    Buus, S; Sette, A; Colon, S M;

    1988-01-01

    Low molecular weight material associated with affinity-purified class II major histocompatibility complex (MHC) molecules of mouse (Ia) had the expected properties of peptides bound to the antigen binding site of Ia. Thus, the low molecular weight material derived from the I-Ad isotype was effici......Low molecular weight material associated with affinity-purified class II major histocompatibility complex (MHC) molecules of mouse (Ia) had the expected properties of peptides bound to the antigen binding site of Ia. Thus, the low molecular weight material derived from the I-Ad isotype...... was predominantly peptide in nature, as shown by its susceptibility to protease digestion. It was heterogeneous as measured by gel filtration (mean molecular weight approximately 3000), and when characterized by high-performance liquid chromatography, it eluted over a wide concentration of solvent. Such self...

  4. Therapeutic DNA vaccine encoding peptide P10 against experimental paracoccidioidomycosis.

    Directory of Open Access Journals (Sweden)

    Glauce M G Rittner

    Full Text Available Paracoccidioidomycosis (PCM, caused by Paracoccidioides brasiliensis, is the most prevalent invasive fungal disease in South America. Systemic mycoses are the 10th most common cause of death among infectious diseases in Brazil and PCM is responsible for more than 50% of deaths due to fungal infections. PCM is typically treated with sulfonamides, amphotericin B or azoles, although complete eradication of the fungus may not occur and relapsing disease is frequently reported. A 15-mer peptide from the major diagnostic antigen gp43, named P10, can induce a strong T-CD4+ helper-1 immune response in mice. The TEPITOPE algorithm and experimental data have confirmed that most HLA-DR molecules can present P10, which suggests that P10 is a candidate antigen for a PCM vaccine. In the current work, the therapeutic efficacy of plasmid immunization with P10 and/or IL-12 inserts was tested in murine models of PCM. When given prior to or after infection with P. brasiliensis virulent Pb 18 isolate, plasmid-vaccination with P10 and/or IL-12 inserts successfully reduced the fungal burden in lungs of infected mice. In fact, intramuscular administration of a combination of plasmids expressing P10 and IL-12 given weekly for one month, followed by single injections every month for 3 months restored normal lung architecture and eradicated the fungus in mice that were infected one month prior to treatment. The data indicate that immunization with these plasmids is a powerful procedure for prevention and treatment of experimental PCM, with the perspective of being also effective in human patients.

  5. Therapeutic DNA Vaccine Encoding Peptide P10 against Experimental Paracoccidioidomycosis

    Science.gov (United States)

    Rittner, Glauce M. G.; Muñoz, Julián E.; Marques, Alexandre F.; Nosanchuk, Joshua D.; Taborda, Carlos P.; Travassos, Luiz R.

    2012-01-01

    Paracoccidioidomycosis (PCM), caused by Paracoccidioides brasiliensis, is the most prevalent invasive fungal disease in South America. Systemic mycoses are the 10th most common cause of death among infectious diseases in Brazil and PCM is responsible for more than 50% of deaths due to fungal infections. PCM is typically treated with sulfonamides, amphotericin B or azoles, although complete eradication of the fungus may not occur and relapsing disease is frequently reported. A 15-mer peptide from the major diagnostic antigen gp43, named P10, can induce a strong T-CD4+ helper-1 immune response in mice. The TEPITOPE algorithm and experimental data have confirmed that most HLA-DR molecules can present P10, which suggests that P10 is a candidate antigen for a PCM vaccine. In the current work, the therapeutic efficacy of plasmid immunization with P10 and/or IL-12 inserts was tested in murine models of PCM. When given prior to or after infection with P. brasiliensis virulent Pb 18 isolate, plasmid-vaccination with P10 and/or IL-12 inserts successfully reduced the fungal burden in lungs of infected mice. In fact, intramuscular administration of a combination of plasmids expressing P10 and IL-12 given weekly for one month, followed by single injections every month for 3 months restored normal lung architecture and eradicated the fungus in mice that were infected one month prior to treatment. The data indicate that immunization with these plasmids is a powerful procedure for prevention and treatment of experimental PCM, with the perspective of being also effective in human patients. PMID:22389734

  6. Chimeric Epitope Vaccine from Multistage Antigens for Lymphatic Filariasis.

    Science.gov (United States)

    Anugraha, G; Madhumathi, J; Prince, P R; Prita, P J Jeya; Khatri, V K; Amdare, N P; Reddy, M V R; Kaliraj, P

    2015-10-01

    Lymphatic filariasis, a mosquito-borne parasitic disease, affects more than 120 million people worldwide. Vaccination for filariasis by targeting different stages of the parasite will be a boon to the existing MDA efforts of WHO which required repeated administration of the drug to reduce the infection level and sustained transmission. Onset of a filaria-specific immune response achieved through antigen vaccines can act synergistically with these drugs to enhance the parasite killing. Multi-epitope vaccine approach has been proved to be successful against several parasitic diseases as it overcomes the limitations associated with the whole antigen vaccines. Earlier results from our group suggested the protective efficacy of multi-epitope vaccine comprising two immunodominant epitopes from Brugia malayi antioxidant thioredoxin (TRX), several epitopes from transglutaminase (TGA) and abundant larval transcript-2 (ALT-2). In this study, the prophylactic efficacy of the filarial epitope protein (FEP), a chimera of selective epitopes identified from our earlier study, was tested in a murine model (jird) of filariasis with L3 larvae. FEP conferred a significantly (P < 0.0001) high protection (69.5%) over the control in jirds. We also observed that the multi-epitope recombinant construct (FEP) induces multiple types of protective immune responses, thus ensuring the successful elimination of the parasite; this poses FEP as a potential vaccine candidate.

  7. Chimeric Epitope Vaccine from Multistage Antigens for Lymphatic Filariasis.

    Science.gov (United States)

    Anugraha, G; Madhumathi, J; Prince, P R; Prita, P J Jeya; Khatri, V K; Amdare, N P; Reddy, M V R; Kaliraj, P

    2015-10-01

    Lymphatic filariasis, a mosquito-borne parasitic disease, affects more than 120 million people worldwide. Vaccination for filariasis by targeting different stages of the parasite will be a boon to the existing MDA efforts of WHO which required repeated administration of the drug to reduce the infection level and sustained transmission. Onset of a filaria-specific immune response achieved through antigen vaccines can act synergistically with these drugs to enhance the parasite killing. Multi-epitope vaccine approach has been proved to be successful against several parasitic diseases as it overcomes the limitations associated with the whole antigen vaccines. Earlier results from our group suggested the protective efficacy of multi-epitope vaccine comprising two immunodominant epitopes from Brugia malayi antioxidant thioredoxin (TRX), several epitopes from transglutaminase (TGA) and abundant larval transcript-2 (ALT-2). In this study, the prophylactic efficacy of the filarial epitope protein (FEP), a chimera of selective epitopes identified from our earlier study, was tested in a murine model (jird) of filariasis with L3 larvae. FEP conferred a significantly (P < 0.0001) high protection (69.5%) over the control in jirds. We also observed that the multi-epitope recombinant construct (FEP) induces multiple types of protective immune responses, thus ensuring the successful elimination of the parasite; this poses FEP as a potential vaccine candidate. PMID:26179420

  8. Candidate Multi-Peptide-Vaccine Against Classical Swine Fever Virus Induces Strong Antibody Response with Predefined Specificity

    Institute of Scientific and Technical Information of China (English)

    张耿; 董晓楠; 陈应华

    2002-01-01

    Previous investigations demonstrated that the envelope glycoprotein E2 (gp55) of classical swine fever virus (CSFV) is the most immunogenic protein. Interestingly, recombinant protein E2 that contains only one structural antigenic unit (unit B/C or A) could protect pigs from a lethal challenge of CSFV. Based on these findings, we designed and prepared five overlapping synthetic peptides that covered the sequence unit B/C (aa 693-777) of Shimen E2 and conjugated individual peptides with bovine serum albumin (BSA). After the vaccination, the specificity of the rabbit sera was analyzed in the enzyme-linked immunosorbent assay (ELISA) and the fast protein liquid chromatography (FPLC). The results show that each of the five candidate peptide-vaccines can successfully induce a high titer of specific antibodies in New Zealand White Rabbits (n=3). Subsequently, the five candidate peptide-vaccines were applied in combination for immunization of pigs (n=10) and induced specific and strong humoral responses against all of the five designed peptides in pigs. Our studies indicate that the candidate multi-peptide-vaccine would prove an excellent marker vaccine against CSFV and provide a model for developing effective synthetic peptide vaccines to stop viral epidemics in humans and animals.

  9. Analysis of Swine Leukocyte Antigen Peptide Binding Profiles and the Identification of T cell Epitopes by Tetramer Staining

    DEFF Research Database (Denmark)

    Pedersen, Lasse Eggers

    within a species makes immune escape almost impossible for any intruding pathogen. Characterization of the SLA class I and class II gene products and their peptide binding capacity defines the T cell epitopes of any given pathogen proteome. To date the analysis of MHC peptide interactions, strength...... class I peptide binding characteristics in relation to immune responses to vaccination or infection. Applying proven technologies to newly produced, recombinant swine leukocyte antigen (SLA) class I proteins yielded a body of data for peptide:SLA:β2m (pSLA) complex affinity and stability. Mapping...... the SLA proteins for their peptide binding requirements along with the identification of their cognate virally derived peptides, made it possible to explore the nature of the SLA proteins and the roles they play in establishing adaptive immunity. The development of SLA tetramers, enabled investigation...

  10. [Peptide vaccine therapy with TLR-9 agonist for patients with esophageal squamous cell carcinoma].

    Science.gov (United States)

    Katsuda, Masahiro; Iwahashi, Makoto; Matsuda, Kenji; Miyazawa, Motoki; Nakamori, Mikihito; Nakamura, Masaki; Naka, Teiji; Ojima, Toshiyasu; Iida, Takeshi; Yamaue, Hiroki

    2011-11-01

    Patients with advanced carcinoma are thought to have an impaired immune surveillance system. Therefore, the potent helper action is required for the induction of an antitumor immune response in such patients. We evaluated the efficacy of CpG-ODN, which is TLR-9 agonist, as cancer vaccine adjuvant through in vitro experiments. We also conducted a phase I clinical trial for patients with advanced esophageal squamous cell carcinoma (ESCC) using peptide vaccine in combination with CpG-B. In vitro experiments showed that CpG-ODN caused various immune-modifications, suggesting an efficacy of CpG-ODN as peptide vaccine adjuvant. Moreover, the immune monitoring data in phase I clinical trial suggested that CpG-B augmented the generation of antigen-specific T cell responses and innate immunity. These data indicated that the vaccination with cancer-testis antigen derived peptide in combination with CpG-B may be useful as a new immunotherapy for patients with advanced ESCC. PMID:22202246

  11. Phase I vaccination trial of SYT-SSX junction peptide in patients with disseminated synovial sarcoma

    Directory of Open Access Journals (Sweden)

    Asanuma Hiroko

    2005-01-01

    Full Text Available Abstract Background Synovial sarcoma is a high-grade malignant tumor of soft tissue, characterized by the specific chromosomal translocation t(X;18, and its resultant SYT-SSX fusion gene. Despite intensive multimodality therapy, the majority of metastatic or relapsed diseases still remain incurable, thus suggesting a need for new therapeutic options. We previously demonstrated the antigenicity of SYT-SSX gene-derived peptides by in vitro analyses. The present study was designed to evaluate in vivo immunological property of a SYT-SSX junction peptide in selected patients with synovial sarcoma. Methods A 9-mer peptide (SYT-SSX B: GYDQIMPKK spanning the SYT-SSX fusion region was synthesized. Eligible patients were those (i who have histologically and genetically confirmed, unresectable synovial sarcoma (SYT-SSX1 or SYT-SSX2 positive, (ii HLA-A*2402 positive, (iii between 20 and 70 years old, (iv ECOG performance status between 0 and 3, and (v who gave informed consent. Vaccinations with SYT-SSX B peptide (0.1 mg or 1.0 mg were given subcutaneously six times at 14-day intervals. These patients were evaluated for DTH skin test, adverse events, tumor size, tetramer staining, and peptide-specific CTL induction. Results A total of 16 vaccinations were carried out in six patients. The results were (i no serious adverse effects or DTH reactions, (ii suppression of tumor progression in one patient, (iii increases in the frequency of peptide-specific CTLs in three patients and a decrease in one patient, and (iv successful induction of peptide-specific CTLs from four patients. Conclusions Our findings indicate the safety of the SYT-SSX junction peptide in the use of vaccination and also give support to the property of the peptide to evoke in vivo immunological responses. Modification of both the peptide itself and the related protocol is required to further improve the therapeutic efficacy.

  12. First Peptide Vaccine Providing Protection against Viral Infection in the Target Animal: Studies of Canine Parvovirus in Dogs.

    NARCIS (Netherlands)

    J.P.M. Langeveld; J. Ignacio Casal; A.D.M.E. Osterhaus (Albert); E. Cortes; R.L. de Swart (Rik); C. Vela (Carmen); K. Dalsgaard (Kristian); W.C. Puijk (Wouter); W.M.M. Schaaper (Wim); R.H. Meloen

    1994-01-01

    textabstractA synthetic peptide vaccine which protects dogs against challenge with virulent canine parvovirus is described. The amino acid sequence used was discovered in previous studies on the immunogenic properties of previously mapped antigenic sites and represents the amino-terminal region of

  13. First peptide vaccine providing protection against viral infection in the target animal: studies of canine parvovirus in dogs.

    NARCIS (Netherlands)

    J.P.M. Langeveld; J.I. Casal; A.D.M.E. Osterhaus (Albert); E. Cortes; R.L. de Swart (Rik); C. Vela (Carmen); K. Dalsgaard (Kristian); W.C. Puijk (Wouter); W.M.M. Schaaper (Wim); R.H. Meloen

    1994-01-01

    textabstractA synthetic peptide vaccine which protects dogs against challenge with virulent canine parvovirus is described. The amino acid sequence used was discovered in previous studies on the immunogenic properties of previously mapped antigenic sites and represents the amino-terminal region of v

  14. Developing Peptide Mimotopes of Capsular Polysaccharides and Lipopolysaccharides Protective Antigens of Pathogenic Burkholderia Bacteria.

    Science.gov (United States)

    Guo, Pengfei; Zhang, Jing; Tsai, Shien; Li, Bingjie; Lo, Shyh-Ching

    2016-06-01

    Burkholderia pseudomallei (BP) and Burkholderia mallei (BM) are two species of pathogenic Burkholderia bacteria. Our laboratory previously identified four monoclonal antibodies (MAbs) that reacted against Burkholderia capsular polysaccharides (PS) and lipopolysaccharides (LPS) and effectively protected against a lethal dose of BP/BM infections in mice. In this study, we used phage display panning against three different phage peptide libraries to select phage clones specifically recognized by each of the four protective MAbs. After sequencing a total of 179 candidate phage clones, we examined in detail six selected phage clones carrying different peptide inserts for the specificity of binding by the respective target MAbs. Chemically synthesized peptides corresponding to those displayed by the six phage clones were conjugated to keyhole limpet hemocyanin carrier protein and tested for their binding specificity to the respective protective MAbs. The study revealed that four of the six peptides, all derived from the library displaying dodecapeptides, functioned well as "mimotopes" of Burkholderia PS and LPS as demonstrated by a high degree of specific competition against the binding of three protective MAbs to BP and BM. Our results suggest that the four selected peptide mimics corresponding to PS/LPS protective antigens of BP and BM could potentially be developed into peptide vaccines against pathogenic Burkholderia bacteria. PMID:27328059

  15. Synthetic peptides with antigenic specificity for bacterial toxins.

    Science.gov (United States)

    Sela, M; Arnon, R; Jacob, C O

    1986-01-01

    The attachment of a diphtheria toxin-specific synthetic antigenic determinant and a synthetic adjuvant to a synthetic polymeric carrier led to production of a totally synthetic macromolecule which provoked protective antibodies against diphtheria when administered in aqueous solution. When peptides related to the B subunit of cholera toxin were synthesized and attached to tetanus toxoid, antibodies produced against the conjugate reacted in some but not all cases with intact cholera toxin and (especially with peptide CTP 3, residues 50-64) neutralized toxin reactivity, as tested by permeability in rabbit skin, fluid accumulation in ligated small intestinal loops and adenylate cyclase activation. Polymerization of the peptide without any external carrier, or conjugation with the dipalmityl lysine group, had as good an effect in enhancing the immune response as its attachment to tetanus toxoid. Prior exposure to the carrier suppressed the immune response to the epitope attached to it, whereas prior exposure to the synthetic peptide had a good priming effect when the intact toxin was given; when two different peptides were attached to the same carrier, both were expressed. Antisera against peptide CTP 3 were highly cross-reactive with the heat-labile toxin of Escherichia coli and neutralized it to the same extent as cholera toxin, which is not surprising in view of the great homology between the two proteins. A synthetic oligonucleotide coding for CTP 3 has been used to express the peptide in a form suitable for immunization. It led to a priming effect against the intact cholera toxin. PMID:2426052

  16. Development of a candidate influenza vaccine based on virus-like particles displaying influenza M2e peptide into the immunodominant loop region of hepatitis B core antigen: Insertion of multiple copies of M2e increases immunogenicity and protective efficiency.

    Science.gov (United States)

    Ravin, Nikolai V; Blokhina, Elena A; Kuprianov, Victor V; Stepanova, Liudmila A; Shaldjan, Aram A; Kovaleva, Anna A; Tsybalova, Liudmila M; Skryabin, Konstantin G

    2015-06-26

    The extracellular domain of the transmembrane protein M2 (M2e) of influenza A virus is a promising target for the development of "universal" vaccines against influenza. M2e is a poor immunogen by itself; however, when M2e is linked to an appropriate carrier, such as hepatitis B virus core (HBc) particles, it becomes highly immunogenic. Insertions of target peptides into the surface-exposed major immunodominant loop region (MIR) of the HBc antigen are especially immunogenic, but such insertions often affect the protein folding and formation of recombinant virus-like particles. To facilitate an appropriate conformation of the M2e insert, we introduced flexible linkers at the junction points between the insert and flanking HBc sequences. This approach allowed the construction of recombinant HBc particles carrying 1, 2 and 4 copies of M2e in the MIR region. These particles were produced in Escherichia coli and purified to homogeneity. The immune response and protective activity of hybrid HBc particles in mice correlated with the number of inserted M2e peptides: the highest immunogenicity and complete protection of mice against the lethal challenge by influenza virus was observed with particles carrying four copies of M2e. The possibility of the simultaneous presentation of M2e peptides from several important influenza strains on a single HBc particle could also facilitate the development of a broad-specificity vaccine efficient not only against influenza A strains of human origin but also for newly emerging strains of animal origin, such as the avian influenza. PMID:25937448

  17. Protective efficacy of bacterial membranes containing surface-exposed BM95 antigenic peptides for the control of cattle tick infestations.

    Science.gov (United States)

    Canales, Mario; Labruna, Marcelo B; Soares, João F; Prudencio, Carlos R; de la Fuente, José

    2009-12-01

    The Rhipicephalus (Boophilus) microplus BM86 and BM95 glycoproteins are homologous proteins that protect cattle against tick infestations. In this study, we demonstrated that the recombinant chimeric protein comprising tick BM95 immunogenic peptides fused to the A. marginale MSP1a N-terminal region for presentation on the Escherichia coli membrane was protective against R. microplus infestations in rabbits. This system provides a novel and simple approach for the production of tick protective antigens by surface display of antigenic protein chimera on live E. coli and suggests the possibility of using recombinant bacterial membrane fractions for vaccination against cattle tick infestations. PMID:19835826

  18. Prospects for T cell immunotherapy of tumours by vaccination with immunodominant and subdominant peptides.

    Science.gov (United States)

    Melief, C J; Kast, W M

    1994-01-01

    Immunotherapy of tumours by adoptive transfer of cytotoxic T lymphocytes (CTL) is now feasible in experimental murine systems. These CTL recognize peptide sequences of defined length presented by major histocompatibility complex (MHC) class I molecules. Effective eradication of large tumour masses requires co-administration of interleukin 2. Tumour escape strategies are numerous but in various instances can be counteracted by defined measures. Initiation of CTL responses against poorly immunogenic virally induced tumours and other tumours requires novel strategies to overcome T cell inertia. We propose a strategy in which CTL are raised against target molecules of choice including differentiation antigens of restricted tissue distribution (autoantigens) or mutated/overexpressed oncogene products. The steps proposed include: (1) identification of target molecules of choice. (2) Identification in these target molecules of peptides fitting MHC allele-specific peptide motifs involved in peptide binding to MHC molecules. (3) Evaluation of actual binding of such peptides to specific MHC class I molecules. (4) In vitro CTL response induction by such peptides, presented by highly efficient antigen-presenting cells such as antigen processing-defective cells carrying empty MHC class I molecules loaded with a single peptide or dendritic cells. Both types of cells are capable of primary CTL response induction in vitro. (5) Evaluation of proper processing by the demonstration of tumour cell lysis by these CTL. (6) Adoptive transfer of tumour-specific CTL generated in vitro or vaccination with peptides. These various steps have now been taken for several viruses, virally induced tumours and other types of tumours and the first indications that this strategy is useful have been obtained. PMID:7796678

  19. Development of a candidate influenza vaccine based on virus-like particles displaying influenza M2e peptide into the immunodominant region of hepatitis B core antigen: Broad protective efficacy of particles carrying four copies of M2e.

    Science.gov (United States)

    Tsybalova, Liudmila M; Stepanova, Liudmila A; Kuprianov, Victor V; Blokhina, Elena A; Potapchuk, Marina V; Korotkov, Alexander V; Gorshkov, Andrey N; Kasyanenko, Marina A; Ravin, Nikolai V; Kiselev, Oleg I

    2015-06-26

    A long-term objective when designing influenza vaccines is to create one with broad cross-reactivity that will provide effective control over influenza, no matter which strain has caused the disease. Here we summarize the results from an investigation into the immunogenic and protective capacities inherent in variations of a recombinant protein, HBc/4M2e. This protein contains four copies of the ectodomain from the influenza virus protein M2 (M2e) fused within the immunodominant loop of the hepatitis B virus core antigen (HBc). Variations of this basic design include preparations containing M2e from the consensus human influenza virus; the M2e from the highly pathogenic avian A/H5N1 virus and a combination of two copies from human and two copies from avian influenza viruses. Intramuscular delivery in mice with preparations containing four identical copies of M2e induced high IgG titers in blood sera and bronchoalveolar lavages. It also provoked the formation of memory T-cells and antibodies were retained in the blood sera for a significant period of time post immunization. Furthermore, these preparations prevented the death of 75-100% of animals, which were challenged with lethal doses of virus. This resulted in a 1.2-3.5 log10 decrease in viral replication within the lungs. Moreover, HBc particles carrying only "human" or "avian" M2e displayed cross-reactivity in relation to human (A/H1N1, A/H2N2 and A/H3N2) or A/H5N1 and A(H1N1)pdm09 viruses, respectively; however, with the particles carrying both "human" and "avian" M2e this effect was much weaker, especially in relation to influenza virus A/H5N1. It is apparent from this work that to quickly produce vaccine for a pandemic it would be necessary to have several variations of a recombinant protein, containing four copies of M2e (each one against a group of likely influenza virus strains) with these relevant constructs housed within a comprehensive collection Escherichia coli-producers and maintained ready for use

  20. Comparable quality attributes of hepatitis E vaccine antigen with and without adjuvant adsorption-dissolution treatment.

    Science.gov (United States)

    Zhang, Yue; Li, Min; Yang, Fan; Li, Yufang; Zheng, Zizheng; Zhang, Xiao; Lin, Qingshan; Wang, Ying; Li, Shaowei; Xia, Ningshao; Zhang, Jun; Zhao, Qinjian

    2015-01-01

    Most vaccines require adjuvants for antigen stabilization and immune potentiation. Aluminum-based adjuvants are the most widely used adjuvants for human vaccines. Previous reports demonstrated the preservation of antigen conformation and other antigen characteristics after recovery from adjuvanted Hepatitis B and human papillomavirus vaccines. In this study, we used a combination of various physiochemical and immunochemical methods to analyze hepatitis E vaccine antigen quality attributes after recovery from adjuvants. All biochemical and biophysical methods showed similar characteristics of the p239 protein after recovery from adjuvanted vaccine formulation compared to the antigen in solution which never experienced adsorption/desorption process. Most importantly, we demonstrated full preservation of key antigen epitopes post-recovery from adjuvanted vaccine using a panel of murine monoclonal antibodies as exquisite probes. Antigenicity of p239 was probed with a panel of 9 mAbs using competition/blocking ELISA, surface plasmon resonance and sandwich ELISA methods. These multifaceted analyses demonstrated the preservation of antigen key epitopes and comparable protein thermal stability when adsorbed on adjuvants or of the recovered antigen post-dissolution treatment. A better understanding of the antigen conformation in adjuvanted vaccine will enhanced our knowledge of antigen-adjuvant interactions and facilitate an improved process control and development of stable vaccine formulation.

  1. Antigen Presentation Ability of Salmonella Carrying DNA Vaccine Model and MCP-3 gene

    Directory of Open Access Journals (Sweden)

    Endang Winiati Bachtiar

    2015-11-01

    Full Text Available The objective of this study is to determine the antigen presentation ability of a DNA vaccine model that is co-delivered with that of recombinant Salmonella enterica serovar Typhimurium (STM1 expressing chemokine macrophage chemotactic protein-3 (MCP-3. The DNA vaccine, pVROVA, was constructed by amplification of the ovalbumin coding region from sOVA-C1. Dendritic cells (DCs were obtained from IL-4 and GMCSF stimulated mouse bone marrow stem cell. Cultured DCs were incubated with STM1 carrying a model ovalbumin gene (pVROVA. Furthermore, MHC class I antigen presentation of a dominant OVA peptide was assayed in vitro. The experiments were designed to determine the effect of co-delivering MCP-3 with that of ovalbumin in STM1. Our results show that a plasmid pROVA-carrying ovalbumin gene was succesfully constructed and sequence analysis of the ovalbumin-coding revealed an identity match of 100% with that of the chicken ovalbumin DNA sequences from the GenBank database. We also found that the presence of the MCP-3 encoding plasmid in STM1 or E. coli DH1 could increase the recovery of both STM1 and E. coli DH1 over those that carry the empty plasmids. Antigen presentation assay also indicates that MCP-3 can positively influence the presentation of ovalbumin. Conclusion: the infection of DCs by STM1-carrying DNA vaccine and MCP-3 results in an increase of processing and presentation of ovalbumin in vitro.Keywords : DNA vaccine, MCP-3, APC, Salmonella, Dendritic cells

  2. A computational method for identification of vaccine targets from protein regions of conserved human leukocyte antigen binding

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn; Simon, Christian; Kudahl, Ulrich J.;

    2015-01-01

    variable regions, where all variants bind HLA. These regions, although variable, can thus be considered stable in terms of HLA binding and represent valuable vaccine targets. Results: We applied this method to predict CD8+ T-cell targets in influenza A H7N9 hemagglutinin and significantly increased the...... number of potential vaccine targets compared to the number of targets discovered using the traditional approach where low-frequency peptides are excluded. Conclusions: We developed a webserver with an intuitive visualization scheme for summarizing the T cell-based antigenic potential of any given protein...

  3. Marked differences in human melanoma antigen-specific T cell responsiveness after vaccination using a functional microarray.

    Directory of Open Access Journals (Sweden)

    Daniel S Chen

    2005-10-01

    Full Text Available BACKGROUND: In contrast to many animal model studies, immunotherapeutic trials in humans suffering from cancer invariably result in a broad range of outcomes, from long-lasting remissions to no discernable effect. METHODS AND FINDINGS: In order to study the T cell responses in patients undergoing a melanoma-associated peptide vaccine trial, we have developed a high-throughput method using arrays of peptide-major histocompatibility complexes (pMHC together with antibodies against secreted factors. T cells were specifically immobilized and activated by binding to particular pMHCs. The antibodies, spotted together with the pMHC, specifically capture cytokines secreted by the T cells. This technique allows rapid, simultaneous isolation and multiparametric functional characterization of antigen-specific T cells present in clinical samples. Analysis of CD8+ lymphocytes from ten melanoma patients after peptide vaccination revealed a diverse set of patient- and antigen-specific profiles of cytokine secretion, indicating surprising differences in their responsiveness. Four out of four patients who showed moderate or greater secretion of both interferon-gamma (IFNgamma and tumor necrosis factor-alpha (TNFalpha in response to a gp100 antigen remained free of melanoma recurrence, whereas only two of six patients who showed discordant secretion of IFNgamma and TNFalpha did so. CONCLUSION: Such multiparametric analysis of T cell antigen specificity and function provides a valuable tool with which to dissect the molecular underpinnings of immune responsiveness and how this information correlates with clinical outcome.

  4. Efficacy of a Vaccine Based on Protective Antigen and Killed Spores against Experimental Inhalational Anthrax▿ ‡

    OpenAIRE

    Gauthier, Yves P.; Tournier, Jean-Nicolas; Paucod, Jean-Charles; Corre, Jean-Philippe; Mock, Michèle; Goossens, Pierre L.; Vidal, Dominique R.

    2008-01-01

    Protective antigen (PA)-based anthrax vaccines acting on toxins are less effective than live attenuated vaccines, suggesting that additional antigens may contribute to protective immunity. Several reports indicate that capsule or spore-associated antigens may enhance the protection afforded by PA. Addition of formaldehyde-inactivated spores (FIS) to PA (PA-FIS) elicits total protection against cutaneous anthrax. Nevertheless, vaccines that are effective against cutaneous anthrax may not be so...

  5. Antigen-Specific Antibody Glycosylation Is Regulated via Vaccination.

    Science.gov (United States)

    Mahan, Alison E; Jennewein, Madeleine F; Suscovich, Todd; Dionne, Kendall; Tedesco, Jacquelynne; Chung, Amy W; Streeck, Hendrik; Pau, Maria; Schuitemaker, Hanneke; Francis, Don; Fast, Patricia; Laufer, Dagna; Walker, Bruce D; Baden, Lindsey; Barouch, Dan H; Alter, Galit

    2016-03-01

    Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain (Fc domain) regulate antibody functionality: changes in antibody subclass and changes in a single N-linked glycan located in the CH2 domain of the IgG Fc. Together, these modifications provide a specific set of instructions to the innate immune system to direct the elimination of antibody-bound antigens. While it is clear that subclass selection is actively regulated during the course of natural infection, it is unclear whether antibody glycosylation can be tuned, in a signal-specific or pathogen-specific manner. Here, we show that antibody glycosylation is determined in an antigen- and pathogen-specific manner during HIV infection. Moreover, while dramatic differences exist in bulk IgG glycosylation among individuals in distinct geographical locations, immunization is able to overcome these differences and elicit antigen-specific antibodies with similar antibody glycosylation patterns. Additionally, distinct vaccine regimens induced different antigen-specific IgG glycosylation profiles, suggesting that antibody glycosylation is not only programmable but can be manipulated via the delivery of distinct inflammatory signals during B cell priming. These data strongly suggest that the immune system naturally drives antibody glycosylation in an antigen-specific manner and highlights a promising means by which next-generation therapeutics and vaccines can harness the antiviral activity of the innate immune system via directed alterations in antibody glycosylation in vivo.  .

  6. Antigen-Specific Antibody Glycosylation Is Regulated via Vaccination.

    Directory of Open Access Journals (Sweden)

    Alison E Mahan

    2016-03-01

    Full Text Available Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain (Fc domain regulate antibody functionality: changes in antibody subclass and changes in a single N-linked glycan located in the CH2 domain of the IgG Fc. Together, these modifications provide a specific set of instructions to the innate immune system to direct the elimination of antibody-bound antigens. While it is clear that subclass selection is actively regulated during the course of natural infection, it is unclear whether antibody glycosylation can be tuned, in a signal-specific or pathogen-specific manner. Here, we show that antibody glycosylation is determined in an antigen- and pathogen-specific manner during HIV infection. Moreover, while dramatic differences exist in bulk IgG glycosylation among individuals in distinct geographical locations, immunization is able to overcome these differences and elicit antigen-specific antibodies with similar antibody glycosylation patterns. Additionally, distinct vaccine regimens induced different antigen-specific IgG glycosylation profiles, suggesting that antibody glycosylation is not only programmable but can be manipulated via the delivery of distinct inflammatory signals during B cell priming. These data strongly suggest that the immune system naturally drives antibody glycosylation in an antigen-specific manner and highlights a promising means by which next-generation therapeutics and vaccines can harness the antiviral activity of the innate immune system via directed alterations in antibody glycosylation in vivo.  .

  7. Probing vaccine antigens against bovine mastitis caused by Streptococcus uberis.

    Science.gov (United States)

    Collado, Rosa; Prenafeta, Antoni; González-González, Luis; Pérez-Pons, Josep Antoni; Sitjà, Marta

    2016-07-19

    Streptococcus uberis is a worldwide pathogen that causes intramammary infections in dairy cattle. Because virulence factors determining the pathogenicity of S. uberis have not been clearly identified so far, a commercial vaccine is not yet available. Different S. uberis strains have the ability to form biofilm in vitro, although the association of this kind of growth with the development of mastitis is unknown. The objective of this study was to evaluate the potential use as vaccine antigens of proteins from S. uberis biofilms, previously identified by proteomic and immunological analyses. The capability of eliciting a protective immune response by targeted candidates was assayed on a murine model. Sera from rabbits immunized with S. uberis biofilm preparations and a convalescent cow intra-mammary infected with S. uberis were probed against cell wall proteins from biofilm and planktonic cells previously separated by two-dimensional gel electrophoresis. Using rabbit immunized serum, two proteins were found to be up-regulated in biofilm cells as compared to planktonic cells; when serum from the convalescent cow was used, up to sixteen biofilm proteins were detected. From these proteins, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), fructose-biphosphate aldolase (FBA), and elongation factor Ts (EFTs) were chosen to be tested as vaccine antigen candidates. For this purpose, different groups of mice were immunized with the three recombinant-expressed proteins (each one formulated separately in a vaccine), and thereafter intraperitoneally challenged with S. uberis. The three proteins induced specific IgG antibodies, but a significant reduction of mortality was only observed in the groups of mice vaccinated with FBA or EFTs. These results suggest that FBA and EFTs might be considered as strong antigenic candidates for a vaccine against S. uberis bovine mastitis. Moreover, this is the first study to indicate that also in S. uberis, GAPDH, FBA and EFTs, as proteins

  8. Probing vaccine antigens against bovine mastitis caused by Streptococcus uberis.

    Science.gov (United States)

    Collado, Rosa; Prenafeta, Antoni; González-González, Luis; Pérez-Pons, Josep Antoni; Sitjà, Marta

    2016-07-19

    Streptococcus uberis is a worldwide pathogen that causes intramammary infections in dairy cattle. Because virulence factors determining the pathogenicity of S. uberis have not been clearly identified so far, a commercial vaccine is not yet available. Different S. uberis strains have the ability to form biofilm in vitro, although the association of this kind of growth with the development of mastitis is unknown. The objective of this study was to evaluate the potential use as vaccine antigens of proteins from S. uberis biofilms, previously identified by proteomic and immunological analyses. The capability of eliciting a protective immune response by targeted candidates was assayed on a murine model. Sera from rabbits immunized with S. uberis biofilm preparations and a convalescent cow intra-mammary infected with S. uberis were probed against cell wall proteins from biofilm and planktonic cells previously separated by two-dimensional gel electrophoresis. Using rabbit immunized serum, two proteins were found to be up-regulated in biofilm cells as compared to planktonic cells; when serum from the convalescent cow was used, up to sixteen biofilm proteins were detected. From these proteins, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), fructose-biphosphate aldolase (FBA), and elongation factor Ts (EFTs) were chosen to be tested as vaccine antigen candidates. For this purpose, different groups of mice were immunized with the three recombinant-expressed proteins (each one formulated separately in a vaccine), and thereafter intraperitoneally challenged with S. uberis. The three proteins induced specific IgG antibodies, but a significant reduction of mortality was only observed in the groups of mice vaccinated with FBA or EFTs. These results suggest that FBA and EFTs might be considered as strong antigenic candidates for a vaccine against S. uberis bovine mastitis. Moreover, this is the first study to indicate that also in S. uberis, GAPDH, FBA and EFTs, as proteins

  9. Elucidating the mechanisms of protein antigen adsorption to the CAF/NAF liposomal vaccine adjuvant systems

    DEFF Research Database (Denmark)

    Hamborg, Mette; Rose, Fabrice; Jorgensen, Lene;

    2014-01-01

    The reverse vaccinology approach has recently resulted in the identification of promising protein antigens, which in combination with appropriate adjuvants can stimulate customized, protective immune responses. Although antigen adsorption to adjuvants influences vaccine efficacy and safety, little...

  10. Antigenic community between Schistosoma mansoni and Biomphalaria glabrata: on the search of candidate antigens for vaccines

    Directory of Open Access Journals (Sweden)

    N Chacón

    2002-10-01

    Full Text Available We have previously confirmed the presence of common antigens between Schistosoma mansoni and its vector, Biomphalaria glabrata. Cross-reactive antigens may be important as possible candidates for vaccine and diagnosis of schistosomiasis. Sera from outbred mice immunized with a soluble Biomphalaria glabrata antigen (SBgA of non-infected B. glabrata snails recognized molecules of SBgA itself and S. mansoni AWA by Western blot. Recognition of several molecules of the SBgA were inhibited by pre-incubation with AWA (16, 30, 36, 60 and 155 kDa. The only specific molecule of AWA, inhibited by SBgA, was a 120 kDa protein. In order to determine which epitopes of SBgA were glycoproteins, the antigen was treated with sodium metaperiodate and compared with non-treated antigen. Molecules of 140, 60 and 24 kDa in the SBgA appear to be glycoproteins. Possible protective effects of the SBgA were evaluated immunizing outbred mice in two different experiments using Freund's Adjuvant. In the first one (12 mice/group, we obtained a significant level of protection (46% in the total worm load, with a high variability in worm recovery. In the second experiment (22 mice/group, no significant protection was observed, neither in worm load nor in egg production per female. Our results suggest that SBgA constitutes a rich source of candidate antigens for diagnosis and prophylactic studies.

  11. Comparative efficacy of Bacillus anthracis live spore vaccine and protective antigen vaccine against anthrax in the guinea pig.

    OpenAIRE

    Little, S F; Knudson, G B

    1986-01-01

    Several strains of Bacillus anthracis have been reported previously to cause fatal infection in immunized guinea pigs. In this study, guinea pigs were immunized with either a protective antigen vaccine or a live Sterne strain spore vaccine, then challenged with virulent B. anthracis strains isolated from various host species from the United States and foreign sources. Confirmation of previously reported studies (which used only protective antigen vaccines) was made with the identification of ...

  12. Vaccination against Experimental Allergic Encephalomyelitis with T Cell Receptor Peptides

    Science.gov (United States)

    Howell, Mark D.; Winters, Steven T.; Olee, Tsaiwei; Powell, Henry C.; Carlo, Dennis J.; Brostoff, Steven W.

    1989-11-01

    Experimental allergic encephalomyelitis (EAE) is an autoimmune disease of the central nervous system mediated by CD4+ T cells reactive with myelin basic protein (MBP). Rats were rendered resistant to the induction of EAE by vaccination with synthetic peptides corresponding to idiotypic determinants of the β chain VDJ region and Jα regions of the T cell receptor (TCR) that are conserved among encephalitogenic T cells. These findings demonstrate the utility of TCR peptide vaccination for modulating the activity of autoreactive T cells and represent a general therapeutic approach for T cell--mediated pathogenesis.

  13. Probing the S1 specificity pocket of the aminopeptidases that generate antigenic peptides

    OpenAIRE

    Zervoudi, Efthalia; Papakyriakou, Athanasios; Georgiadou, Dimitra; Evnouchidou, Irini; Gajda, Anna; Poreba, Marcin; Salvesen, Guy S.; Drag, Marcin; Hattori, Akira; Swevers, Luc; Vourloumis, Dionisios; Stratikos, Efstratios

    2011-01-01

    Abstract ER aminopeptidase 1 (ERAP1), ER aminopeptidase 2 (ERAP2) and Insulin Regulated aminopeptidase (IRAP) are three homologous enzymes that play critical roles in the generation of antigenic peptides. These aminopeptidases excise amino acids from N-terminally extended precursors of antigenic peptides in order to generate the correct length epitopes for binding onto MHC class I molecules. The specificity of these peptidases can affect antigenic peptide selection, but has not yet...

  14. Delivery of vaccine peptides by rapid conjugation to baculovirus particles.

    Science.gov (United States)

    Wilson, Sarah; Baird, Margaret; Ward, Vernon K

    2008-05-12

    Baculoviruses deliver strong activation signals to dendritic cells and can promote potent immune responses. These properties can be harnessed to use baculovirus as an adjuvant and carrier particle for immunogenic peptides. In this study we use a chemical linker to couple peptides to the baculovirus Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV). Intranasal delivery of baculovirus coupled with immunogenic peptides to mice elicited antigen-specific IgG1 and IgG2a antibody. Furthermore, antigen-specific IgA was detected in the lung, and an IFN-gamma response was observed upon re-stimulation with antigen. We show that chemical coupling enables the rapid modification of AcMNPV, allowing multiple epitopes to be delivered simultaneously on a self-adjuvanting carrier particle. PMID:18417258

  15. Vaccination with lipid core peptides fails to induce epitope-specific T cell responses but confers non-specific protective immunity in a malaria model.

    Directory of Open Access Journals (Sweden)

    Simon H Apte

    Full Text Available Vaccines against many pathogens for which conventional approaches have failed remain an unmet public health priority. Synthetic peptide-based vaccines offer an attractive alternative to whole protein and whole organism vaccines, particularly for complex pathogens that cause chronic infection. Previously, we have reported a promising lipid core peptide (LCP vaccine delivery system that incorporates the antigen, carrier, and adjuvant in a single molecular entity. LCP vaccines have been used to deliver several peptide subunit-based vaccine candidates and induced high titre functional antibodies and protected against Group A streptococcus in mice. Herein, we have evaluated whether LCP constructs incorporating defined CD4(+ and/or CD8(+ T cell epitopes could induce epitope-specific T cell responses and protect against pathogen challenge in a rodent malaria model. We show that LCP vaccines failed to induce an expansion of antigen-specific CD8(+ T cells following primary immunization or by boosting. We further demonstrated that the LCP vaccines induced a non-specific type 2 polarized cytokine response, rather than an epitope-specific canonical CD8(+ T cell type 1 response. Cytotoxic responses of unknown specificity were also induced. These non-specific responses were able to protect against parasite challenge. These data demonstrate that vaccination with lipid core peptides fails to induce canonical epitope-specific T cell responses, at least in our rodent model, but can nonetheless confer non-specific protective immunity against Plasmodium parasite challenge.

  16. Generation and Characterization of Human Monoclonal Antibodies Targeting Anthrax Protective Antigen following Vaccination with a Recombinant Protective Antigen Vaccine.

    Science.gov (United States)

    Chi, Xiangyang; Li, Jianmin; Liu, Weicen; Wang, Xiaolin; Yin, Kexin; Liu, Ju; Zai, Xiaodong; Li, Liangliang; Song, Xiaohong; Zhang, Jun; Zhang, Xiaopeng; Yin, Ying; Fu, Ling; Xu, Junjie; Yu, Changming; Chen, Wei

    2015-05-01

    The anthrax protective antigen (PA) is the central component of the three-part anthrax toxin, and it is the primary immunogenic component in the approved AVA anthrax vaccine and the "next-generation" recombinant PA (rPA) anthrax vaccines. Animal models have indicated that PA-specific antibodies (AB) are sufficient to protect against infection with Bacillus anthracis. In this study, we investigated the PA domain specificity, affinity, mechanisms of neutralization, and synergistic effects of PA-specific antibodies from a single donor following vaccination with the rPA vaccine. Antibody-secreting cells were isolated 7 days after the donor received a boost vaccination, and 34 fully human monoclonal antibodies (hMAb) were identified. Clones 8H6, 4A3, and 22F1 were able to neutralize lethal toxin (LeTx) both in vitro and in vivo. Clone 8H6 neutralized LeTx by preventing furin cleavage of PA in a dose-dependent manner. Clone 4A3 enhanced degradation of nicked PA, thereby interfering with PA oligomerization. The mechanism of 22F1 is still unclear. A fourth clone, 2A6, that was protective only in vitro was found to be neutralizing in vivo in combination with a toxin-enhancing antibody, 8A7, which binds to domain 3 of PA and PA oligomers. These results provide novel insights into the antibody response elicited by the rPA vaccine and may be useful for PA-based vaccine and immunotherapeutic cocktail design. PMID:25787135

  17. In silico design of discontinuous peptides representative of B and T-cell epitopes from HER2-ECD as potential novel cancer peptide vaccines.

    Science.gov (United States)

    Manijeh, Mahdavi; Mehrnaz, Keyhanfar; Violaine, Moreau; Hassan, Mohabatkar; Abbas, Jafarian; Mohammad, Rabbani

    2013-01-01

    At present, the most common cause of cancer-related death in women is breast cancer. In a large proportion of breast cancers, there is the overexpression of human epidermal growth factor receptor 2 (HER2). This receptor is a 185 KDa growth factor glycoprotein, also known as the first tumor-associated antigen for different types of breast cancers. Moreover, HER2 is an appropriate cell-surface specific antigen for passive immunotherapy, which relies on the repeated application of monoclonal antibodies that are transferred to the patient. However, vaccination is preferable because it would stimulate a patient's own immune system to actively respond to a disease. In the current study, several bioinformatics tools were used for designing synthetic peptide vaccines. PEPOP was used to predict peptides from HER2 ECD subdomain III in the form of discontinuous-continuous B-cell epitopes. Then, T-cell epitope prediction web servers MHCPred, SYFPEITHI, HLA peptide motif search, Propred, and SVMHC were used to identify class-I and II MHC peptides. In this way, PEPOP selected 12 discontinuous peptides from the 3D structure of the HER2 ECD subdomain III. Furthermore, T-cell epitope prediction analyses identified four peptides containing the segments 77 (384-391) and 99 (495-503) for both B and T-cell epitopes. This work is the only study to our knowledge focusing on design of in silico potential novel cancer peptide vaccines of the HER2 ECD subdomain III that contain epitopes for both B and T-cells. These findings based on bioinformatics analyses may be used in vaccine design and cancer therapy; saving time and minimizing the number of tests needed to select the best possible epitopes.

  18. A bicomponent Plasmodium falciparum investigational vaccine composed of protein-peptide conjugates.

    Science.gov (United States)

    Kubler-Kielb, Joanna; Majadly, Fathy; Biesova, Zuzana; Mocca, Christopher P; Guo, Chunyan; Nussenzweig, Ruth; Nussenzweig, Victor; Mishra, Satish; Wu, Yimin; Miller, Louis H; Keith, Jerry M; Liu, Teh-Yung; Robbins, John B; Schneerson, Rachel

    2010-01-19

    There is yet no licensed vaccine against malaria, a serious human disease affecting mostly children, with an annual death rate of about one million. Plasmodia, the malaria-causing parasites, have two obligatory hosts: mammals or birds, in which they multiply asexually, and mosquitoes with sexual multiplication. The most common and serious type of malaria is caused by Plasmodium falciparum. The circumsporozoite protein (CSP), a major surface antigen of sporozoites, is a protective antigen. A unique feature of P. falciparum CSP is its large central domain composed of over 30 tetrapeptide repeats of Asn-Ala-Asn-Pro (NANP). Several NANP peptide-protein conjugates were tested clinically but elicited a low level of CSP antibodies for a short duration. To provide a CSP-based candidate vaccine, we investigated recombinant CSP and NANP conjugates of various peptide lengths, with different N-terminal amino acids, bound at different ratios to various carrier proteins. Injected into mice, CSP alone and CSP or NANP conjugates induced antibodies with booster responses and were positive by the sporozoite immunofluorescent assay. The use of the mosquito stage P. falciparum ookinete surface protein, Pfs25, cross-linked onto itself as a carrier for NANP, induced in mice high levels of uniquely long-lasting antibodies to both vaccine components with secondary biological activities, that will provide immunity to liver infection by sporozoites and block transmission by mosquitoes.

  19. Identification of peptide sequences as a measure of Anthrax vaccine stability during storage.

    Science.gov (United States)

    Whiting, Gail; Wheeler, Jun X; Rijpkema, Sjoerd

    2014-01-01

    The UK anthrax vaccine is an alum precipitate of a sterile filtrate of Bacillus anthracis Sterne culture (AVP). An increase in shelf life of AVP from 3 to 5 years prompted us to investigate the in vivo potency and the antigen content of 12 batches with a shelf life of 6.4 to 9.9 years and one bulk with a shelf life of 23.8 years. All batches, except for a 9.4-year-old batch, passed the potency test. Mass spectrometry (MS) and in-gel difference 2-dimensional gel electrophoresis (DIGE) were used to examine antigens of the pellet and supernatant of AVP. The pellet contained proteins with a MW in excess of 15 kDa. DIGE of desorbed proteins from the pellet revealed that with aging, 19 spots showed a significant change in size or intensity, a sign of protein degradation. MS identified 21 proteins including protective antigen (PA), enolase, lethal factor (LF), nucleoside diphosphate kinase, edema factor, and S-layer proteins. Fifteen proteins were detected for the first time including metabolic enzymes, iron binding proteins, and manganese dependent superoxide dismutase (MnSOD). The supernatant contained131 peptide sequences. Peptides representing septum formation inhibitor protein and repeat domain protein were most abundant. Five proteins were shared with the pellet: 2,3,4,5-tetrahydropyridine-6-dicarboxylate N-succinyltransferase, enolase, LF, MnSOD, and PA. The number of peptide sequences increased with age. Peptides from PA and LF appeared once batches exceeded their shelf life by 2 and 4 years, respectively. In conclusion, changes in antigen content resulting from decay or desorption only had a limited effect on in vivo potency of AVP. The presence of PA and LF peptides in the supernatant can inform on the age and stability of AVP. PMID:24637775

  20. Design of the ATAQ peptide and its evaluation as an immunogen to develop a Rhipicephalus vaccine.

    Science.gov (United States)

    Aguirre, André de Abreu Rangel; Lobo, Francisco Pereira; Cunha, Rodrigo Casquero; Garcia, Marcos Valério; Andreotti, Renato

    2016-05-15

    Tick infestation may cause several problems including affecting domestic animal health and reducing the production of meat and milk, among others. Resistance to several classes of acaricides have been reported, forcing researchers to search for alternative measures, such as vaccines against ticks, to ensure tick control while having no or at least low negative impacts on the environment and public health. However, the current commercially available vaccines in different strains of Rhipicephalus microplus are reported to be of low efficacy. Fortunately, reverse vaccinology approaches have shown positive results in the new generation of vaccines. On this basis, a synthetic peptide from the ATAQ protein, which is present in the gut and Malpighi tubes of R. microplus, was synthesized. The ATAQ proteins were isolated, characterized and sequenced from several species of the genus Rhipicephalus. The alignment showed 93.3% identity among DNA sequences of ATAQs from these species. Because of this, immunization trials with this peptide were conducted on mice, rabbits and cattle to evaluate the humoral immune response and the efficacy against Rhipicephalus sanguineus in addition to R. microplus. Based on recent results, we conclude that reverse vaccinology is a promising approach because it is more accurate and faster than conventional methods in the detection of potential antigens to use in anti-tick vaccines. It is not only applicable against R. microplus but also against tick species that play important roles in spreading other diseases. ATAQ proteins should be considered as the antigen in new trials to develop a multi-antigenic vaccine. Although these peptides behave as hapten and are not able to be recognized by the immune system on its own, using carriers and adjuvants helps its presentation and induces strong immune responses. Furthermore, an efficiency of 35% reduction in overall life cycle parameters was reported for R. microplus (98% for ELISA responder animals) and

  1. Design of a heterosubtypic epitope-based peptide vaccine fused with hemokinin-1 against influenza viruses

    Institute of Scientific and Technical Information of China (English)

    Shahla; Shahsavandi; Mohammad; Majid; Ebrahimi; Kaveh; Sadeghi; Homayoon; Mahravani

    2015-01-01

    Influenza viruses continue to emerge and re-emerge, posing new threats for public health. Control and treatment of influenza depends mainly on vaccination and chemoprophylaxis with approved antiviral drugs. Identification of specific epitopes derived from influenza viruses has significantly advanced the development of epitope-based vaccines. Here, we explore the idea of using HLA binding data to design an epitope-based vaccine that can elicit heterosubtypic T-cell responses against circulating H7N9, H5N1, and H9N2 subtypes. The hemokinin-1(HK-1) peptide sequence was used to induce immune responses against the influenza viruses. Five conserved high score cytotoxic T lymphocyte(CTL) epitopes restricted to HLA-A*0201-binding peptides within the hemagglutinin(HA) protein of the viruses were chosen, and two HA CTL/HK-1 chimera protein models designed. Using in silico analysis, which involves interferon epitope scanning, protein structure prediction, antigenic epitope determination, and model quality evaluation, chimeric proteins were designed. The applicability of one of these proteins as a heterosubtypic epitopebased vaccine candidate was analyzed.

  2. TH1 and TH2 responses are influenced by HLA antigens in healthy neonates vaccinated with recombinant hepatitis B vaccine.

    OpenAIRE

    Abdollah Jafarzadeh; Fazel Shokri

    2012-01-01

    The immune response to hepatitis B surface antigen (HBsAg) is influenced by several factors, of which HLA antigens and balanced secretion of Th1/Th2 cytokines play important roles. The aim of this study was to evaluate the influence of HLA antigens on cytokine secretion by HBsAg-stimulated peripheral blood mononuclear cells (PBMC) from healthy neonates vaccinated with recombinant HBsAg. PBMCs were isolated from 48 Iranian neonates vaccinated with a recombinant HBV vaccine. The cells were stim...

  3. Proteome-wide antigen discovery of novel protective vaccine candidates against Staphylococcus aureus infection

    DEFF Research Database (Denmark)

    Rasmussen, Karina Juhl; Mattsson, Andreas Holm; Pilely, Katrine;

    2016-01-01

    is an urgent need to institute non-antimicrobial measures, such as vaccination, against the spread of MRSA. With the aim of finding new protective antigens for vaccine development, this study used a proteome-wide in silico antigen prediction platform to screen the proteome of S. aureus strain MRSA252...

  4. Booster Vaccination: The Role of Reduced Antigen Content Vaccines as a Preschool Booster

    Directory of Open Access Journals (Sweden)

    Giovanni Gabutti

    2014-01-01

    Full Text Available The need for boosters for tetanus, diphtheria, pertussis, and polio, starting from preschool age, is related to the waning immune protection conferred by vaccination, the elimination/reduction of natural boosters due to large-scale immunization programs, and the possibility of reintroduction of wild agents from endemic areas. Taking into account the relevance of safety/tolerability in the compliance with vaccination among the population, it have been assessed whether today enough scientific evidences are available to support the use of dTap-IPV booster in preschool age. The review of the literature was conducted using the PubMed search engine. A total of 41 works has been selected; besides, the documentation produced by the World Health Organization, the European Centre for Disease Control, and the Italian Ministry of Health has been consulted. Many recent papers confirm the opportunity to use a low antigenic dose vaccine starting from 4 to 6 years of age. There is also evidence that 10 years after immunization the rate of seroprotected subjects against diphtheria does not differ significantly between those vaccinated with paediatric dose (DTaP or reduced dose (dTaP or dTap product. The dTpa vaccine is highly immunogenic for diphtheria toxoids regardless of prior vaccination history (2 + 1 and 3 + 1 schedules.

  5. [Subunit vaccines--antigens, carriers, conjugation methods and the role of adjuvants].

    Science.gov (United States)

    Jarząb, Anna; Skowicki, Michał; Witkowska, Danuta

    2013-11-27

    Vaccines are effective tools protecting against the development of infectious diseases caused by pathogenic microorganisms. Currently, we have vaccines protecting against many infections, where standard therapy is not only difficult but often impossible due to the ever-progressive increase in bacterial resistance to many available antibiotics. Among vaccines which have been used in the prevention of infection are the traditional vaccines containing live, killed or attenuated strains of microorganisms. However, it should be noted that such vaccines are not always effective, especially when the expected immune response is directed against specific antigens. Subunit vaccines belong to new generation vaccines and have gained more and more interest in recent years. These vaccines contain fragments of pathogenic microorganisms, which are highly purified and immunogenic antigens. Using these purified antigens excludes the risk of post-vaccination infection. In addition, subunit vaccines minimize side-effects associated with the use of whole bacterial cells. The paper discusses the most promising and the most tested antigens, vaccine carriers, conjugation methods and vaccine delivery systems which are being used in the design of subunit vaccines. This paper also highlights the advantages and disadvantages of adjuvants, which are substances to support the immune response in humans, and the relationship between adjuvants' efficacy and their mechanism of action.

  6. Mimotope-based vaccines of Leishmania infantum antigens and their protective efficacy against visceral leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Lourena Emanuele Costa

    Full Text Available BACKGROUND: The development of cost-effective prophylactic strategies to prevent leishmaniasis has become a high-priority. The present study has used the phage display technology to identify new immunogens, which were evaluated as vaccines in the murine model of visceral leishmaniasis (VL. Epitope-based immunogens, represented by phage-fused peptides that mimic Leishmania infantum antigens, were selected according to their affinity to antibodies from asymptomatic and symptomatic VL dogs' sera. METHODOLOGY/MAIN FINDINGS: Twenty phage clones were selected after three selection cycles, and were evaluated by means of in vitro assays of the immune stimulation of spleen cells derived from naive and chronically infected with L. infantum BALB/c mice. Clones that were able to induce specific Th1 immune response, represented by high levels of IFN-γ and low levels of IL-4 were selected, and based on their selectivity and specificity, two clones, namely B10 and C01, were further employed in the vaccination protocols. BALB/c mice vaccinated with clones plus saponin showed both a high and specific production of IFN-γ, IL-12, and GM-CSF after in vitro stimulation with individual clones or L. infantum extracts. Additionally, these animals, when compared to control groups (saline, saponin, wild-type phage plus saponin, or non-relevant phage clone plus saponin, showed significant reductions in the parasite burden in the liver, spleen, bone marrow, and paws' draining lymph nodes. Protection was associated with an IL-12-dependent production of IFN-γ, mainly by CD8+ T cells, against parasite proteins. These animals also presented decreased parasite-mediated IL-4 and IL-10 responses, and increased levels of parasite-specific IgG2a antibodies. CONCLUSIONS/SIGNIFICANCE: This study describes two phage clones that mimic L. infantum antigens, which were directly used as immunogens in vaccines and presented Th1-type immune responses, and that significantly reduced the

  7. Immunogenicity of multiple antigen peptides containing Plasmodium vivax CS epitopes in BALB/c mice

    Directory of Open Access Journals (Sweden)

    Myriam A. Herrera

    1994-01-01

    Full Text Available Multiple antigen peptide systems (MAPs allow the incorporation of various epitopes in to a single synthetic peptide immunogen. We have characterized the immune response of BALB/c mice to a series of MAPs assembled with different B and T cell epitopes derived from the Plasmodium vivax circumsporozoite (CS protein. A B-cell epitope from the central repeat domain and two T-cell epitopes from the amino and carboxyl flanking regions were used to assembled eight different MAPs. An additional universal T cell epitope (ptt-30 from tetanus toxin protein was included. Immunogenicity in terms of antibody responses and in vitro T lymphocyte proliferation was evaluated. MAPs containing B and T cell epitopes induced high titers of anti-peptides antibodies, which recognized the native protein on sporozoites as determined by IFAT. The antibody specificity was also determined by a competitive inhibition assay with different MAPs. A MAP containing the B cell epitope (p11 and the universal epitope ptt-30 together with another composed of p11 and the promiscuous T cell epitope (p25 proved to be the most immunogenic. The strong antibody response and specificity for the cognate protein indicates that further studies designed to assess the potential of these proteins as human malaria vaccine candidates are warranted.

  8. Invariant chain as a vehicle to load antigenic peptides on human MHC class I for cytotoxic T-cell activation.

    Science.gov (United States)

    Wälchli, Sébastien; Kumari, Shraddha; Fallang, Lars-Egil; Sand, Kine M K; Yang, Weiwen; Landsverk, Ole J B; Bakke, Oddmund; Olweus, Johanna; Gregers, Tone F

    2014-03-01

    Protective T-cell responses depend on efficient presentation of antigen (Ag) in the context of major histocompatibility complex class I (MHCI) and class II (MHCII) molecules. Invariant chain (Ii) serves as a chaperone for MHCII molecules and mediates trafficking to the endosomal pathway. The genetic exchange of the class II-associated Ii peptide (CLIP) with antigenic peptides has proven efficient for loading of MHCII and activation of specific CD4(+) T cells. Here, we investigated if Ii could similarly activate human CD8(+) T cells when used as a vehicle for cytotoxic T-cell (CTL) epitopes. The results show that wild type Ii, and Ii in which CLIP was replaced by known CTL epitopes from the cancer targets MART-1 or CD20, coprecipitated with HLA-A*02:01 and mediated colocalization in the endosomal pathway. Furthermore, HLA-A*02:01-positive cells expressing CLIP-replaced Ii efficiently activated Ag-specific CD8(+) T cells in a TAP- and proteasome-independent manner. Finally, dendritic cells transfected with mRNA encoding IiMART-1 or IiCD20 primed naïve CD8(+) T cells. The results show that Ii carrying antigenic peptides in the CLIP region can promote efficient presentation of the epitopes to CTLs independently of the classical MHCI peptide loading machinery, facilitating novel vaccination strategies against cancer.

  9. Effect of particulate adjuvant on the anthrax protective antigen dose required for effective nasal vaccination.

    Science.gov (United States)

    Bento, Dulce; Staats, Herman F; Borges, Olga

    2015-07-17

    Successful vaccine development is dependent on the development of effective adjuvants since the poor immunogenicity of modern subunit vaccines typically requires the use of potent adjuvants and high antigen doses. In recent years, adjuvant formulations combining both immunopotentiators and delivery systems have emerged as a promising strategy to develop effective and improved vaccines. In this study we investigate if the association of the mast cell activating adjuvant compound 48/80 (C48/80) with chitosan nanoparticles would promote an antigen dose sparing effect when administered intranasally. Even though the induction of strong mucosal immunity required higher antigen doses, incorporation of C48/80 into nanoparticles provided significant dose sparing when compared to antigen and C48/80 in solution with no significant effect on serum neutralizing antibodies titers. These results suggest the potential of this novel adjuvant combination to improve the immunogenicity of a vaccine and decrease the antigen dose required for vaccination. PMID:26087299

  10. Peptide Based Vaccine Approaches for Cancer—A Novel Approach Using a WT-1 Synthetic Long Peptide and the IRX-2 Immunomodulatory Regimen

    International Nuclear Information System (INIS)

    Therapeutic cancer vaccines have the potential to generate a long lasting immune response that will destroy tumor cells with specificity and safety, in contrast to many other current cancer therapies. Clinical success to date has been limited by a number of factors including choice of immunogenic cancer rejection antigens, optimization of vaccine platforms and immune adjuvants to effectively polarize the immune response, and incorporation of strategies to reverse cancer mediated immune suppression by utilization of effective adjuvant/immune modulators. WT-1 (Wilms' tumor gene 1) is a cancer antigen that is required for tumorigenesis, expressed in a high percentage of tumor cells and rarely expressed in adult normal cells. Moreover spontaneous immunity to WT-1 is seen in cancer patients and can be augmented with various therapeutic vaccine approaches. IRX-2 is an immune modulator with demonstrated preclinical and clinical pleiotropic immune activities including enhancement of the immune response to potential tumor antigens. This paper presents the rationale and preclinical data for utilizing the WT-1 tumor antigen in a novel vaccine platform consisting of a synthetic long peptide containing multiple class I and class II epitopes in combination with the IRX-2 immunomodulatory regimen to overcome immuno-suppressive pathways and enhance the anti-tumor response

  11. Control of tick infestations in cattle vaccinated with bacterial membranes containing surface-exposed tick protective antigens.

    Science.gov (United States)

    Almazán, Consuelo; Moreno-Cantú, Orlando; Moreno-Cid, Juan A; Galindo, Ruth C; Canales, Mario; Villar, Margarita; de la Fuente, José

    2012-01-01

    Vaccines containing the Rhipicephalus (Boophilus) microplus BM86 and BM95 antigens protect cattle against tick infestations. Tick subolesin (SUB), elongation factor 1a (EF1a) and ubiquitin (UBQ) are new candidate protective antigens for the control of cattle tick infestations. Previous studies showed that R. microplus BM95 immunogenic peptides fused to the Anaplasma marginale major surface protein (MSP) 1a N-terminal region (BM95-MSP1a) for presentation on the Escherichia coli membrane were protective against R. microplus infestations in rabbits. In this study, we extended these results by expressing SUB-MSP1a, EF1a-MSP1a and UBQ-MSP1a fusion proteins on the E. coli membrane using this system and demonstrating that bacterial membranes containing the chimeric proteins BM95-MSP1a and SUB-MSP1a were protective (>60% vaccine efficacy) against experimental R. microplus and Rhipicephalus annulatus infestations in cattle. This system provides a novel, simple and cost-effective approach for the production of tick protective antigens by surface display of antigenic protein chimera on the E. coli membrane and demonstrates the possibility of using recombinant bacterial membrane fractions in vaccine preparations to protect cattle against tick infestations. PMID:22085549

  12. Carbohydrate Biopolymers Enhance Antibody Responses to Mucosally Delivered Vaccine Antigens

    Science.gov (United States)

    Bacon, A.; Makin, J.; Sizer, P. J.; Jabbal-Gill, I.; Hinchcliffe, M.; Illum, L.; Chatfield, S.; Roberts, M.

    2000-01-01

    We have evaluated the ability of two carbohydrate biopolymers, chitosan and gellan, to enhance antibody responses to subunit influenza virus vaccines delivered to the respiratory tracts of mice. Groups of mice were vaccinated three times intranasally (i.n.) with 10 μg of purified influenza B/Panama virus surface antigens (PSAs), which consist of hemagglutinin (HA) and neuraminidase (NA), either alone or admixed with chitosan or gellan solutions. Separate groups were vaccinated subcutaneously (s.c.) with PSAs adsorbed to Alhydrogel or chitosan or gellan alone i.n. Serum antibody responses were determined by enzyme-linked immunosorbent assay (ELISA) for influenza virus-specific immunoglobulin G (IgG) and by HA inhibition (HAI) and NA inhibition (NAI) assays. The local respiratory immune response was measured by assaying for influenza virus-specific IgA antibody in nasal secretions and by enumerating nasal and pulmonary lymphocytes secreting IgA, IgG, and IgM anti-influenza virus-specific antibodies by enzyme-linked immunospotting (ELISPOT). When administered alone i.n., B/Panama PSA was poorly immunogenic. Parenteral immunization with B/Panama PSA with Alhydrogel elicited high titers of anti-B/Panama antibodies in serum but a very poor respiratory anti-B/Panama IgA response. In contrast, i.n. immunization with PSA plus chitosan stimulated very strong local and systemic anti-B/Panama responses. Gellan also enhanced the local and serum antibody responses to i.n. PSA but not to the same extent as chitosan. The ability of chitosan to augment the immunogenicity of influenza vaccines given i.n. was confirmed using PSA prepared from an influenza A virus (A/Texas H1N1). PMID:10992483

  13. Primary vaccination of adults with reduced antigen-content diphtheria-tetanus-acellular pertussis or dTpa-inactivated poliovirus vaccines compared to diphtheria-tetanus-toxoid vaccines.

    NARCIS (Netherlands)

    Theeten, H.; Rumke, H.C.; Hoppener, F.J.; Vilatimo, R.; Narejos, S.; Damme, P. van; Hoet, B.

    2007-01-01

    OBJECTIVE: To evaluate immunogenicity and reactogenicity of primary vaccination with reduced-antigen-content diphtheria-tetanus-acellular pertussis (dTpa) or dTpa-inactivated poliovirus (dTpa-IPV) vaccine compared to diphtheria-tetanus-toxoid vaccines (Td) in adults > or = 40 years of age without

  14. Exposed and concealed antigens as vaccine targets for controlling ticks and tick-borne diseases.

    Science.gov (United States)

    Nuttall, P A; Trimnell, A R; Kazimirova, M; Labuda, M

    2006-04-01

    Tick vaccines derived from Bm86, a midgut membrane-bound protein of the cattle tick, Boophilus microplus, are currently the only commercially available ectoparasite vaccines. Despite its introduction to the market in 1994, and the recognized need for alternatives to chemical pesticides, progress in developing effective antitick vaccines (and ectoparasite vaccines in general) is slow. The primary rate-limiting step is the identification of suitable antigenic targets for vaccine development. Two sources of candidate vaccine antigens have been identified: 'exposed' antigens that are secreted in tick saliva during attachment and feeding on a host and 'concealed' antigens that are normally hidden from the host. Recently, a third group of antigens has been distinguished that combines the properties of both exposed and concealed antigens. This latter group offers the prospect of a broad-spectrum vaccine effective against both adults and immature stages of a wide variety of tick species. It also shows transmission-blocking and protective activity against a tick-borne pathogen. With the proliferation of molecular techniques and their application to vaccine development, there are high hopes for new and effective antitick vaccines that also control tick-borne diseases. PMID:16542317

  15. Evaluation of peptide selection approaches for epitope‐based vaccine design

    DEFF Research Database (Denmark)

    Schubert, B.; Lund, Ole; Nielsen, Morten

    2013-01-01

    , no thorough comparison between the current methods has been realized. Using human immunodeficiency virus as test case, different EV selection algorithms were evaluated with respect to their ability to select small peptides sets with broad coverage of allelic and pathogenic diversity. The methods were compared...... in terms of in silico measurements simulating important vaccine properties like the ability of inducing protection against a multivariant pathogen in a population; the predicted immunogenicity; pathogen, allele, and population coverage; as well as the conservation of selected epitopes. Additionally, we...... evaluate the use of human leukocyte antigen (HLA) supertypes with regards to their applicability for population-spanning vaccine design. The results showed that in terms of induced protection methods that simultaneously aim to optimize pathogen and HLA coverage significantly outperform methods focusing...

  16. Therapy of established B16-F10 melanoma tumors by a single vaccination of CTL/T helper peptides in VacciMax®

    Directory of Open Access Journals (Sweden)

    Korets-Smith Ella

    2007-04-01

    Full Text Available Abstract Background Melanoma tumors are known to express antigens that usually induce weak immune responses of short duration. Expression of both tumor-associated antigens p53 and TRP2 by melanoma cells raises the possibility of simultaneously targeting more than one antigen in a therapeutic vaccine. In this report, we show that VacciMax® (VM, a novel liposome-based vaccine delivery platform, can increase the immunogenicity of melanoma associated antigens, resulting in tumor elimination. Methods C57BL/6 mice bearing B16-F10 melanoma tumors were vaccinated subcutaneously 6 days post tumor implantation with a mixture of synthetic peptides (modified p53: 232–240, TRP-2: 181–188 and PADRE and CpG. Tumor growth was monitored and antigen-specific splenocyte responses were assayed by ELISPOT. Results Vaccine formulated in VM increased the number of both TRP2- and p53-specific IFN-γ producing splenocytes following a single vaccination. Vaccine formulated without VM resulted only in enhanced IFN-γ producing splenocytes to one CTL epitopes (TRP2:180–188, suggesting that VM overcomes antigen dominance and enhances immunogenicity of multiple epitopes. Vaccination of mice bearing 6-day old B16-F10 tumors with both TRP2 and p53-peptides formulated in VM successfully eradicated tumors in all mice. A control vaccine which contained all ingredients except liposomes resulted in eradication of tumors in no more than 20% of mice. Conclusion A single administration of VM is capable of inducing an effective CTL response to multiple tumor-associated antigens. The responses generated were able to reject 6-day old B16-F10 tumors.

  17. Expression of HIV-1 antigens in plants as potential subunit vaccines

    Directory of Open Access Journals (Sweden)

    Tanzer Fiona L

    2008-06-01

    Full Text Available Abstract Background Human immunodeficiency virus type 1 (HIV-1 has infected more than 40 million people worldwide, mainly in sub-Saharan Africa. The high prevalence of HIV-1 subtype C in southern Africa necessitates the development of cheap, effective vaccines. One means of production is the use of plants, for which a number of different techniques have been successfully developed. HIV-1 Pr55Gag is a promising HIV-1 vaccine candidate: we compared the expression of this and a truncated Gag (p17/p24 and the p24 capsid subunit in Nicotiana spp. using transgenic plants and transient expression via Agrobacterium tumefaciens and recombinant tobamovirus vectors. We also investigated the influence of subcellular localisation of recombinant protein to the chloroplast and the endoplasmic reticulum (ER on protein yield. We partially purified a selected vaccine candidate and tested its stimulation of a humoral and cellular immune response in mice. Results Both transient and transgenic expression of the HIV antigens were successful, although expression of Pr55Gag was low in all systems; however, the Agrobacterium-mediated transient expression of p24 and p17/p24 yielded best, to more than 1 mg p24/kg fresh weight. Chloroplast targeted protein levels were highest in transient and transgenic expression of p24 and p17/p24. The transiently-expressed p17/p24 was not immunogenic in mice as a homologous vaccine, but it significantly boosted a humoral and T cell immune response primed by a gag DNA vaccine, pTHGagC. Conclusion Transient agroinfiltration was best for expression of all of the recombinant proteins tested, and p24 and p17/p24 were expressed at much higher levels than Pr55Gag. Our results highlight the usefulness of plastid signal peptides in enhancing the production of recombinant proteins meant for use as vaccines. The p17/p24 protein effectively boosted T cell and humoral responses in mice primed by the DNA vaccine pTHGagC, showing that this plant

  18. The role of B. pertussis vaccine antigen gene variants in pertussis resurgence and possible consequences for vaccine development.

    Science.gov (United States)

    Preston, Andrew

    2016-05-01

    Whooping cough, or pertussis, caused by Bordetella pertussis is considered resurgent in a number of countries world-wide, despite continued high level vaccine coverage. Among a number of causes for this that have been proposed, is the emergence of B. pertussis strains expressing variants of the antigens contained in acellular pertussis vaccines; i.e. the evolution of B. pertussis toward vaccine escape. This commentary highlights the contradictory nature of evidence for this but also discusses the importance of understanding the role of B. pertussis adaptation to vaccine-mediated immune selection pressures for vaccine-mediated pertussis control strategies.

  19. Efficacy demonstration of tetanus vaccines by double antigen ELISA.

    Science.gov (United States)

    Rosskopf, U; Noeske, K; Werner, E

    2005-09-01

    This paper describes a double antigen ELISA (DAE) for rapid, specific and reliable assessment of the antitetanus immune status of horses and sheep. Compared with the indirect ELISA, the double antigen ELISA has the advantage of species-independent testing of sera. Thanks to its test design, it is more specific since the detected antibodies are forced to bind tetanus toxoid twice. In addition, it is very sensitive to tetanus antibodies, enabling the detection of low antibody titres, in range which is relevant for the assessment of the protective status (tetanus toxin neutralising antibodies). The detection limit of the DAE for tetanus antibodies is in the order of 10(-4) EU/ml. A comparison of in vitro results of individual sera with in vivo titres showed that horse sera with titres of 0.04 and 0.05 EU/ml in the DAE showed titres of > 0.05 IU and 0.034 IU/ml respectively during in vivo testing thus indicating good agreement. For tested sheep sera which were rated > 0.05 IU/ml in vivo, the corresponding titre in the DAE was 0.24 EU/ml. Clear tetanus antitoxin establishment of protective ELISA limits requires further comparative examination of sera with low titres (marketing authorisation procedures of tetanus vaccines ad us. vet. As a consequence, the toxin neutralisation test (still being the standard method of choice for quantifying tetanus toxin neutralising antitoxin titres) could be replaced, since it requires too great a number of animals per test and involves considerable suffering for the animals. The test described here reduces the use of mice and guinea pigs within vaccine efficacy testing. In addition, it involves less exposure of the laboratory personnel to toxin.

  20. Airway administration of a highly versatile peptide-based liposomal construct for local and distant antitumoral vaccination.

    Science.gov (United States)

    Kakhi, Zahra; Frisch, Benoît; Bourel-Bonnet, Line; Hemmerlé, Joseph; Pons, Françoise; Heurtault, Béatrice

    2015-12-30

    With the discovery of tumor-associated antigens such as ErbB2, vaccination is considered as a promising strategy to prevent the development of cancer or treat the existing disease. Among routes of immunization, the respiratory route provides the opportunity to develop non-invasive approach for vaccine delivery. In the current study, this administration route was used in order to investigate the potency of a highly versatile di-epitopic liposomal construct to exhibit local or distant antitumoral efficiency after prophylactic or therapeutic vaccination in mice. Well-characterized liposomes, containing the ErbB2 (p63-71) TCD8(+) and HA (p307-319) TCD4(+) peptide epitopes and the Pam2CAG adjuvant, were formulated and administered into the airway of naïve BALB/c mice. The nanoparticle vaccine candidate induced local and specific systemic immune response, as measured by immune cell infiltration and chemokine and cytokine production in BALF or lung tissue, and by spleen T-cell activation ex vivo, respectively. This potent immune response resulted in an efficient antitumor activity against both lung and solid s.c. tumors. Interestingly, the antitumor efficacy was observed after both prophylactic and therapeutic vaccinations, which are the most judicious ones to fight cancer. Our data showed an undeniable interest of liposomal peptide-based vaccines in antitumor vaccination by the respiratory route, opening new perspectives for cancer treatment.

  1. Detection of Avian Antigen-Specific T Cells Induced by Viral Vaccines

    DEFF Research Database (Denmark)

    Dalgaard, Tina Sørensen; Norup, Liselotte Rothmann; Juul-Madsen, Helle Risdahl

    2016-01-01

    Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen. There is ......Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen...... in the cells even throughout division. This leads to daughter cells containing half the fluorescence of their parents. When lymphocytes are loaded with CFSE prior to ex vivo stimulation with specific antigen, the measurement of serial halving of its fluorescence by flow cytometry identifies the cells...

  2. Analysis of Antibody Responses to Protective Antigen-Based Anthrax Vaccines through Use of Competitive Assays▿

    OpenAIRE

    Rebecca A Brady; Verma, Anita; Meade, Bruce D.; Burns, Drusilla L.

    2010-01-01

    The licensed anthrax vaccine and many of the new anthrax vaccines being developed are based on protective antigen (PA), a nontoxic component of anthrax toxin. For this reason, an understanding of the immune response to PA vaccination is important. In this study, we examined the antibody response elicited by PA-based vaccines and identified the domains of PA that contribute to that response in humans as well as nonhuman primates (NHPs) and rabbits, animal species that will be used to generate ...

  3. A Review of Intra- and Extracellular Antigen Delivery Systems for Virus Vaccines of Finfish.

    Science.gov (United States)

    Munang'andu, Hetron Mweemba; Evensen, Øystein

    2015-01-01

    Vaccine efficacy in aquaculture has for a long time depended on evaluating relative percent survival and antibody responses after vaccination. However, current advances in vaccine immunology show that the route in which antigens are delivered into cells is deterministic of the type of adaptive immune response evoked by vaccination. Antigens delivered by the intracellular route induce MHC-I restricted CD8+ responses while antigens presented through the extracellular route activate MHC-II restricted CD4+ responses implying that the route of antigen delivery is a conduit to induction of B- or T-cell immune responses. In finfish, different antigen delivery systems have been explored that include live, DNA, inactivated whole virus, fusion protein, virus-like particles, and subunit vaccines although mechanisms linking these delivery systems to protective immunity have not been studied in detail. Hence, in this review we provide a synopsis of different strategies used to administer viral antigens via the intra- or extracellular compartments. Further, we highlight the differences in immune responses induced by antigens processed by the endogenous route compared to exogenously processed antigens. Overall, we anticipate that the synopsis put together in this review will shed insights into limitations and successes of the current vaccination strategies used in finfish vaccinology.

  4. A Review of Intra- and Extracellular Antigen Delivery Systems for Virus Vaccines of Finfish

    Directory of Open Access Journals (Sweden)

    Hetron Mweemba Munang’andu

    2015-01-01

    Full Text Available Vaccine efficacy in aquaculture has for a long time depended on evaluating relative percent survival and antibody responses after vaccination. However, current advances in vaccine immunology show that the route in which antigens are delivered into cells is deterministic of the type of adaptive immune response evoked by vaccination. Antigens delivered by the intracellular route induce MHC-I restricted CD8+ responses while antigens presented through the extracellular route activate MHC-II restricted CD4+ responses implying that the route of antigen delivery is a conduit to induction of B- or T-cell immune responses. In finfish, different antigen delivery systems have been explored that include live, DNA, inactivated whole virus, fusion protein, virus-like particles, and subunit vaccines although mechanisms linking these delivery systems to protective immunity have not been studied in detail. Hence, in this review we provide a synopsis of different strategies used to administer viral antigens via the intra- or extracellular compartments. Further, we highlight the differences in immune responses induced by antigens processed by the endogenous route compared to exogenously processed antigens. Overall, we anticipate that the synopsis put together in this review will shed insights into limitations and successes of the current vaccination strategies used in finfish vaccinology.

  5. Protection against Mucosal SHIV Challenge by Peptide and Helper-Dependent Adenovirus Vaccines

    Directory of Open Access Journals (Sweden)

    K. Jagannadha Sastry

    2009-11-01

    Full Text Available Groups of rhesus macaques that had previously been immunized with HIV-1 envelope (env peptides and first generation adenovirus serotype 5 (FG-Ad5 vaccines expressing the same peptides were immunized intramuscularly three times with helperdependent adenovirus (HD-Ad vaccines expressing only the HIV-1 envelope from JRFL. No gag, pol, or other SHIV genes were used for vaccination. One group of the FG-Ad5-immune animals was immunized three times with HD-Ad5 expressing env. One group was immunized by serotype-switching with HD-Ad6, HD-Ad1, and HD-Ad2 expressing env. Previous work demonstrated that serum antibody levels against env were significantly higher in the serotype-switched group than in the HD-Ad5 group. In this study, neutralizing antibody and T cell responses were compared between the groups before and after rectal challenge with CCR5-tropic SHIV-SF162P3. When serum samples were assayed for neutralizing antibodies, only weak activity was observed. T cell responses against env epitopes were higher in the serotype-switched group. When these animals were challenged rectally with SHIV-SF162P3, both the Ad5 and serotype-switch groups significantly reduced peak viral loads 2 to 10-fold 2 weeks after infection. Peak viral loads were significantly lower for the serotype-switched group as compared to the HD-Ad5-immunized group. Viral loads declined over 18 weeks after infection with some animals viremia reducing nearly 4 logs from the peak. These data demonstrate significant mucosal vaccine effects after immunization with only env antigens. These data also demonstrate HD-Ad vectors are a robust platform for vaccination.

  6. Multimerized HIV-gp41-derived peptides as fusion inhibitors and vaccines.

    Science.gov (United States)

    Nomura, Wataru; Mizuguchi, Takaaki; Tamamura, Hirokazu

    2016-11-01

    To date, several antigens based on the amino-terminal leucine/isoleucine heptad repeat (NHR) region of an HIV-1 envelope protein gp41 and fusion inhibitors based on the carboxy-terminal leucine/isoleucine heptad repeat (CHR) region of gp41 have been reported. We have developed a synthetic antigen targeting the membrane-fusion mechanism of HIV-1. This uses a template designed with C3-symmetric linkers and mimics the trimeric form of the NHR-derived peptide N36. The antiserum obtained by immunization of the N36 trimeric antigen binds preferentially to the N36 trimer and blocks HIV-1 infection effectively, compared with the antiserum obtained by immunization of the N36 monomer. Using another template designed with different C3-symmetric linkers, we have also developed a synthetic peptide mimicking the trimeric form of the CHR-derived peptide C34, with ∼100 times the inhibitory activity against the HIV-1 fusion mechanism than that of the monomer C34 peptide. A dimeric derivative of C34 has potent inhibitory activity at almost the same levels as this C34 trimer mimic, suggesting that presence of a dimeric form of C34 is structurally critical for fusion inhibitors. As examples of rising mid-size drugs, this review describes an effective strategy for the design of HIV vaccines and fusion inhibitors based on a relationship with the native structure of proteins involved in HIV fusion mechanisms. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 622-628, 2016. PMID:26583370

  7. A Novel Contraceptive Vaccine:Design and Synthesis of the Chimeric Peptide Containing Multivalent Sperm-Specific Epitopes

    Institute of Scientific and Technical Information of China (English)

    何畏; 梁志清; 史常旭; 李玉清

    2001-01-01

    Objective To develop a novel multivalent chimeric peptide vaccine for bisexual fertility regulation Materials & Methods On the basis of the amino acid sequence of the two peptides respectively selected from the mouse sperm/testis-specific proteins SP17 and Cyritestin, and one T cell epitope in bovine ribonuclease (RNase), a novel chimeric peptide consisting of 35 amino acid was designed and subsequently synthesized on the 430A peptide synthesizer. After being emulified with the equivalence Freund's adjuvant, the peptide with 35 amino acid residues was used to immunogenity the female BALB/c mice to investigate its immunity.Results The peptide was successfully synthesized, after being purified in high performance liquid chromatography (HPLC), its purity reached 95%. The specific antisera collected from the immunogenity mice could identify the corresponding proteins of testis tissues of mice, rats and human. The highest specific IgG titer in serum was 1:6 000, while the IgA titer in the washing of vaginal mucous membrane was 1:300.Conclusion The antibodies from the peptide with specific amino acid sequence can identify the original antigens, and stimulate powerful specific humoral immunity in mice. It provides a experimental bases for polyvalent contraceptive vaccine study.

  8. STING activator c-di-GMP enhances the anti-tumor effects of peptide vaccines in melanoma-bearing mice.

    Science.gov (United States)

    Wang, Zili; Celis, Esteban

    2015-08-01

    Therapeutic vaccines to induce anti-tumor CD8 T cells have been used in clinical trials for advanced melanoma patients, but the clinical response rate and overall survival time have not improved much. We believe that these dismal outcomes are caused by inadequate number of antigen-specific CD8 T cells generated by most vaccines. In contrast, huge CD8 T cell responses readily occur during acute viral infections. High levels of type-I interferon (IFN-I) are produced during these infections, and this cytokine not only exhibits anti-viral activity but also promotes CD8 T cell responses. The studies described here were performed to determine whether promoting the production of IFN-I could enhance the potency of a peptide vaccine. We report that cyclic diguanylate monophosphate (c-di-GMP), which activates the stimulator of interferon genes, potentiated the immunogenicity and anti-tumor effects of a peptide vaccine against mouse B16 melanoma. The synergistic effects of c-di-GMP required co-administration of costimulatory anti-CD40 antibody, the adjuvant poly-IC, and were mediated in part by IFN-I. These findings demonstrate that peptides representing CD8 T cell epitopes can be effective inducers of large CD8 T cell responses in vaccination strategies that mimic acute viral infections.

  9. Designing Peptide-Based HIV Vaccine for Chinese

    Directory of Open Access Journals (Sweden)

    Jiayi Shu

    2014-01-01

    Full Text Available CD4+ T cells are central to the induction and maintenance of CD8+ T cell and antibody-producing B cell responses, and the latter are essential for the protection against disease in subjects with HIV infection. How to elicit HIV-specific CD4+ T cell responses in a given population using vaccines is one of the major areas of current HIV vaccine research. To design vaccine that targets specifically Chinese, we assembled a database that is comprised of sequences from 821 Chinese HIV isolates and 46 human leukocyte antigen (HLA DR alleles identified in Chinese population. We then predicted 20 potential HIV epitopes using bioinformatics approaches. The combination of these 20 epitopes has a theoretical coverage of 98.1% of the population for both the prevalent HIV genotypes and also Chinese HLA-DR types. We suggest that testing this vaccine experimentally will facilitate the development of a CD4+ T cell vaccine especially catered for Chinese.

  10. Structural Characterization by NMR of a Double Phosphorylated Chimeric Peptide Vaccine for Treatment of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Stefan Berger

    2013-04-01

    Full Text Available Rational design of peptide vaccines becomes important for the treatment of some diseases such as Alzheimer’s disease (AD and related disorders. In this study, as part of a larger effort to explore correlations of structure and activity, we attempt to characterize the doubly phosphorylated chimeric peptide vaccine targeting a hyperphosphorylated epitope of the Tau protein. The 28-mer linear chimeric peptide consists of the double phosphorylated B cell epitope Tau229-237[pThr231/pSer235] and the immunomodulatory T cell epitope Ag85B241-255 originating from the well-known antigen Ag85B of the Mycobacterium tuberculosis, linked by a four amino acid sequence -GPSL-. NMR chemical shift analysis of our construct demonstrated that the synthesized peptide is essentially unfolded with a tendency to form a β-turn due to the linker. In conclusion, the -GPSL- unit presumably connects the two parts of the vaccine without transferring any structural information from one part to the other. Therefore, the double phosphorylated epitope of the Tau peptide is flexible and accessible.

  11. Targeting DNA vaccines to myeloid cells using a small peptide.

    Science.gov (United States)

    Ye, Chunting; Choi, Jang Gi; Abraham, Sojan; Shankar, Premlata; Manjunath, N

    2015-01-01

    Targeting DNA vaccines to dendritic cells (DCs) greatly enhances immunity. Although several approaches have been used to target protein Ags to DCs, currently there is no method that targets DNA vaccines directly to DCs. Here, we show that a small peptide derived from the rabies virus glycoprotein fused to protamine residues (RVG-P) can target DNA to myeloid cells, including DCs, which results in enhanced humoral and T-cell responses. DCs targeted with a DNA vaccine encoding the immunodominant vaccinia B8R gene via RVG-P were able to restimulate vaccinia-specific memory T cells in vitro. Importantly, a single i.v. injection of B8R gene bound to RVG-P was able to prime a vaccinia-specific T-cell response that was able to rapidly clear a subsequent vaccinia challenge in mice. Moreover, delivery of DNA in DCs was enough to induce DC maturation and efficient Ag presentation without the need for adjuvants. Finally, immunization of mice with a DNA-vaccine encoding West Nile virus (WNV) prM and E proteins via RVG-P elicited high titers of WNV-neutralizing Abs that protected mice from lethal WNV challenge. Thus, RVG-P provides a reagent to target DNA vaccines to myeloid cells and elicit robust T-cell and humoral immune responses.

  12. Vaccination with map specific peptides reduces map burden in tissues of infected goats

    DEFF Research Database (Denmark)

    Melvang, Heidi Mikkelsen; Hassan, Sufia Butt; Thakur, Aneesh;

    As an alternative to protein-based vaccines, we investigated the effect of post-exposure vaccination with Map specific peptides in a goat model aiming at developing a Map vaccine that will neither interfere with diagnosis of paratuberculosis nor bovine tuberculosis. Peptides were initially select...... in the unvaccinated control group seroconverted in ID Screen® ELISA at last sampling prior to euthanasia. These results indicate that a subunit vaccine against Map can induce a protective immune response against paratuberculosis in goats....

  13. Production of schistosome antigens for immunodiagnosis and vaccines: the role of recombinant DNA technology

    International Nuclear Information System (INIS)

    A major problem to confront biochemists studying the immunology of parasitic infection is a paucity of the organisms themselves. Conventional biochemical techniques for the isolation and purification of individual antigens are inappropriate. This problem has been alleviated by the application of recombinant DNA technology. It is now possible to produce large quantities of individual antigens by cloning the corresponding genes into plasmids (or other vectors) and subsequent expression in bacteria. Antigens produced in this way may provide the basis of a specific diagnostic test and vaccines. This paper describes the identification of cDNA clones of Schistosoma mansoni which encode a major egg antigen and schistosomula surface antigens. These antigens are thought to be species specific and may form the basis of a diagnostic test. The schistosomula antigens are also possible candidates for inclusion in an experimental vaccine against infection with S. mansoni. (author)

  14. Antigenic Cartography of H9 Avian Influenza Virus and Its Application to Vaccine Selection.

    Science.gov (United States)

    Wang, Yue; Davidson, Irit; Fouchier, Ron; Spackman, Erica

    2016-05-01

    Vaccination is frequently used as a control method for the H9 subtype of low pathogenicity avian influenza virus (AIV), which is widespread in Asia and the Middle East. One of the most important factors for selecting an effective vaccine strain is the antigenic match between the hemagglutinin protein of the vaccine and the strain circulating in the field. To demonstrate the antigenic relationships among H9 AIVs, with a focus on Israeli H9 isolates, antigenic cartography was used to develop a map of H9 AIVs. Based on their antigenic diversity, three isolates from Israel were selected for vaccination-challenge studies: 1) the current vaccine virus, A/chicken/Israel/215/2007 H9N2 (Ck/215); 2) A/chicken/Israel/1163/2011 H9N2 (Ck/1163); and 3) A/ostrich/Israel/1436/2003 (Os/1436). A 50% infective dose (ID50) model was used to determine the effect of the vaccines on susceptibility to infection by using a standardized dose of vaccine. Sera collected immediately prior to challenge showed that Ck/215 was the most immunogenic, followed by Ck/1163 and Os/1436. A significant difference in ID50 was only observed with Ck/215 homologous challenge, where the ID50 was increased by 2 log 10 per bird. The ID50 for Ck/1163 was the same, regardless of vaccine, including sham vaccination. The ID50 for Os/1436 was above the maximum possible dose and therefore could not be established.

  15. Innovative bioinformatic approaches for developing peptide-based vaccines against hypervariable viruses.

    Science.gov (United States)

    Sirskyj, Danylo; Diaz-Mitoma, Francisco; Golshani, Ashkan; Kumar, Ashok; Azizi, Ali

    2011-01-01

    The application of the fields of pharmacogenomics and pharmacogenetics to vaccine design has been recently labeled 'vaccinomics'. This newly named area of vaccine research, heavily intertwined with bioinformatics, seems to be leading the charge in developing novel vaccines for currently unmet medical needs against hypervariable viruses such as human immunodeficiency virus (HIV), hepatitis C and emerging avian and swine influenza. Some of the more recent bioinformatic approaches in the area of vaccine research include the use of epitope determination and prediction algorithms for exploring the use of peptide epitopes as vaccine immunogens. This paper briefly discusses and explores some current uses of bioinformatics in vaccine design toward the pursuit of peptide vaccines for hypervariable viruses. The various informatics and vaccine design strategies attempted by other groups toward hypervariable viruses will also be briefly examined, along with the strategy used by our group in the design and synthesis of peptide immunogens for candidate HIV and influenza vaccines.

  16. Cancer immunotherapy using novel tumor-associated antigenic peptides identified by genome-wide cDNA microarray analyses.

    Science.gov (United States)

    Nishimura, Yasuharu; Tomita, Yusuke; Yuno, Akira; Yoshitake, Yoshihiro; Shinohara, Masanori

    2015-05-01

    Recent genome-wide cDNA microarray analysis of gene expression profiles in comprehensive tumor types coupled with isolation of cancer tissues by laser-microbeam microdissection have revealed ideal tumor-associated antigens (TAAs) that are frequently overexpressed in various cancers including head and neck squamous cell cancer (HNSCC) and lung cancer, but not in most normal tissues except for testis, placenta, and fetal organs. Preclinical studies using HLA-transgenic mice and human T cells in vitro showed that TAA-derived CTL-epitope short peptides (SPs) are highly immunogenic and induce HLA-A2 or -A24-restricted CTLs. Based on the accumulated evidence, we carried out a phase II clinical trial of the TAA-SP vaccine in advanced 37 HNSCC patients. This study showed a significant induction of TAA-specific CTLs in the majority of patients without serious adverse effects. Importantly, clinical responses including a complete response were observed in this study. Another phase II clinical trial of therapeutic TAA-SP vaccine, designed to evaluate the ability of prevention of recurrence, is ongoing in HNSCC patients who have received curative operations. Further studies in human preclinical studies and in vivo studies using HLA class I transgenic mice showed TAA-derived long peptides (TAA-LPs) have the capacity to induce not only promiscuous HLA class II-restricted CD4(+) T helper type 1 cells but also tumor-specific CTLs through a cross-presentation mechanism. Moreover, we observed an augmentation of TAA-LP-specific T helper type 1 cell responses and tumor antigen-spreading in HNSCC patients vaccinated with TAA-SPs. This accumulated evidence suggests that therapeutic TAA-SPs and LPs vaccines may provide a promising cancer immunotherapy.

  17. WT1 Peptide Cancer Vaccine for Patients with Hematopoietic Malignancies and Solid Cancers

    Directory of Open Access Journals (Sweden)

    Yoshihiro Oka

    2007-01-01

    Full Text Available Wild-type Wilms' tumor gene WT1 is expressed at a high level in hematopoietic malignancies including acute leukemia, chronic myelogenous leukemia, and myelodysplastic syndromes, as well as in various kinds of solid cancers. Human cytotoxic T lymphocytes (CTLs, which could specifically lyse WT1-expressing tumor cells with HLA class I restriction, were generated in vitro. It was also demonstrated that mice immunized with the WT1 peptide rejected challenges by WT1-expressing cancer cells and survived with no signs of autoaggression to normal organs that physiologically expressed WT1. Furthermore, we and others detected IgM and IgG WT1 antibodies in patients with hematopoietic malignancies, indicating that the WT1 protein was highly immunogenic, and that immunoglobulin class-switch-inducing, WT1-specific, cellular immune responses were elicited in these patients. CD8+ WT1-specific CTLs were also detected in peripheral blood or tumor-draining lymph nodes of cancer patients. These results provided us with the rationale for elicitation of CTL responses targeting the WT1 product for cancer immunotherapy. On the basis of these findings, we performed a phase I clinical trial of a WT1 peptide cancer vaccine for the patients with malignant neoplasms. These results strongly suggested that the WT1 peptide cancer vaccine had efficacy in the clinical setting because clinical responses, including reduction of leukemic blast cells or regression of tumor masses, were observed after the WT1 vaccination in patients with hematopoietic malignancies or solid cancers. The power of a tumor-associated-antigen (TAA-derived cancer vaccine may be enhanced in combination with stronger adjuvants, helper peptide, molecular-target-based drugs, or some chemotherapy drugs, such as gemcitabine, which has been revealed to suppress regulartory T-cell function. In contrast, reduction of WT1 peptide dose may be needed for the treatment of patients with hematological stem cell diseases

  18. Non-cytolytic antigen clearance in DNA-vaccinated mice with electropotation

    Institute of Scientific and Technical Information of China (English)

    Jin-liang PENG; Yong-gang ZHAO; Jun-hua MAI; Wen-ka PANG; Wei GUO; Guang-ming CHEN; Guo-yu MO; Gui-rong RAO; Yu-hong XU

    2007-01-01

    Aim: To explore the potential of electroporation (EP)-mediated hepatitis B virus (HBV) DNA vaccination for the treatment of chronic HBV infection. Methods: BALB/c mice were vaccinated with HBV DNA vaccine encoding for the HBV preS2-S antigen, combined with or without EP. HBV surface antigen expression plasmid was administered into mice liver via a hydrodynamic injection to mimic HBV infection. The clearance of antigen in the serum and liver was detected by ELISA assay and immunohistochemical staining. The histopathology of the liver tissues was examined by HE staining and serum alanine aminotransferase assay.Results: The immunogenicity ofHBV DNA vaccine encoding for the HBV preS2-S antigen can be improved by EP-mediated vaccine delivery. The elicited immune responses can indeed reduce the expression of HBV surface antigen (HBsAg) in hepatocytes of the mouse model that was transfected to express HBsAg using the hydrodynamic injection method. The antigen clearance process did not cause significant toxicity to liver tissue, suggesting a non-cytolytic mechanism. Conclusion: The EP-aided DNA vaccination may have potential in mediating viral clearance in chronic hepatitis B patients.

  19. Targeted delivery of an antigenic peptide to the endoplasmic reticulum: application for development of a peptide therapy for ankylosing spondylitis.

    Directory of Open Access Journals (Sweden)

    Hui-Chun Yu

    Full Text Available The development of suitable methods to deliver peptides specifically to the endoplasmic reticulum (ER can provide some potential therapeutic applications of such peptides. Ankylosing spondylitis (AS is strongly associated with the expression of human leukocytic antigen-B27 (HLA-B27. HLA-B27 heavy chain (HC has a propensity to fold slowly resulting in the accumulation of misfolded HLA-B27 HC in the ER, triggering the unfolded protein response, and forming a homodimer, (B27-HC2. Natural killer cells and T-helper 17 cells are then activated, contributing to the major pathogenic potentials of AS. The HLA-B27 HC is thus an important target, and delivery of an HLA-B27-binding peptide to the ER capable of promoting HLA-B27 HC folding is a potential mechanism for AS therapy. Here, we demonstrate that a His6-ubiquitin-tagged Tat-derived peptide (THU can deliver an HLA-B27-binding peptide to the ER promoting HLA-B27 HC folding. The THU-HLA-B27-binding peptide fusion protein crossed the cell membrane to the cytosol through the Tat-derived peptide. The HLA-B27-binding peptide was specifically cleaved from THU by cytosolic ubiquitin C-terminal hydrolases and subsequently transported into the ER by the transporter associated with antigen processing. This approach has potential application in the development of peptide therapy for AS.

  20. Design and Antigenic Epitopes Prediction of a New Trial Recombinant Multiepitopic Rotaviral Vaccine: In Silico Analyses.

    Science.gov (United States)

    Jafarpour, Sima; Ayat, Hoda; Ahadi, Ali Mohammad

    2015-01-01

    Rotavirus is the major etiologic factor of severe diarrheal disease. Natural infection provides protection against subsequent rotavirus infection and diarrhea. This research presents a new vaccine designed based on computational models. In this study, three types of epitopes are considered-linear, conformational, and combinational-in a proposed model protein. Several studies on rotavirus vaccines have shown that VP6 and VP4 proteins are good candidates for vaccine production. In the present study, a fusion protein was designed as a new generation of rotavirus vaccines by bioinformatics analyses. This model-based study using ABCpred, BCPREDS, Bcepred, and Ellipro web servers showed that the peptide presented in this article has the necessary properties to act as a vaccine. Prediction of linear B-cell epitopes of peptides is helpful to investigate whether these peptides are able to activate humoral immunity.

  1. Design and Antigenic Epitopes Prediction of a New Trial Recombinant Multiepitopic Rotaviral Vaccine: In Silico Analyses.

    Science.gov (United States)

    Jafarpour, Sima; Ayat, Hoda; Ahadi, Ali Mohammad

    2015-01-01

    Rotavirus is the major etiologic factor of severe diarrheal disease. Natural infection provides protection against subsequent rotavirus infection and diarrhea. This research presents a new vaccine designed based on computational models. In this study, three types of epitopes are considered-linear, conformational, and combinational-in a proposed model protein. Several studies on rotavirus vaccines have shown that VP6 and VP4 proteins are good candidates for vaccine production. In the present study, a fusion protein was designed as a new generation of rotavirus vaccines by bioinformatics analyses. This model-based study using ABCpred, BCPREDS, Bcepred, and Ellipro web servers showed that the peptide presented in this article has the necessary properties to act as a vaccine. Prediction of linear B-cell epitopes of peptides is helpful to investigate whether these peptides are able to activate humoral immunity. PMID:25965449

  2. Antigenic cartography of H9N2 virus and its impact on the vaccine efficacy in chickens

    Science.gov (United States)

    The H9 subtype of avian influenza virus (AIV) is wide-spread in Asia and the Middle East. The efficacy of vaccines is enhanced by the antigenic match of the hemagglutinin protein (HA) between the vaccine and the field strain. To determine how antigenic variations affect the vaccine efficacy, speci...

  3. Analysis of H7 avian influenza viruses by antigenic cartography and correlation to protection by vaccination

    Science.gov (United States)

    The H7 hemagglutinin subtype one of the most common subtypes of avian influenza virus (AIV) in poultry world wide and since it has the potential to become highly pathogenic it is among the priority subtypes for vaccination. Selection of the optimal vaccine seed strains may now be aided by antigenic...

  4. Functional mimicry of a discontinuous antigenic site by a designed synthetic peptide

    NARCIS (Netherlands)

    Villen, J.; Borras, E.; Schaaper, W.M.M.; Meloen, R.H.; Davila, M.; Domingo, E.; Giralt, E.; Andreu, D.

    2002-01-01

    Functional reproduction of the discontinuous antigenic site D of foot-and-mouth disease virus (FMDV) has been achieved by means of synthetic peptide constructions that integrate each of the three protein loops that define the antigenic site into a single molecule. The site D mimics were designed on

  5. Limitations of plasmid vaccines to complex viruses: selected myxoma virus antigens as DNA vaccines were not protective.

    Science.gov (United States)

    Adams, Mathew M; van Leeuwen, Barbara H; Kerr, Peter J

    2004-11-25

    Myxoma virus, a poxvirus of the genus Leporipoxvirus, is the causative agent of the disease myxomatosis which is highly lethal in European rabbits (Oryctolagus cuniculus). Current vaccines to protect against myxomatosis are either attenuated live strains of the virus or the antigenically related rabbit fibroma virus. We examined the immune response of outbred domestic rabbits to the individual myxoma virus antigens M055R, M073R, M115L and M121R, delivered as DNA vaccines co-expressing rabbit interleukin-2 or interleukin-4. M115L and M121R were also delivered simultaneously. None of the vaccine constructs were able to protect the rabbits from disease or reduce mortality after challenge with virulent myxoma virus, despite induction of antigen-specific cell-mediated and humoral immune responses. PMID:15531037

  6. Full protection in mink against mink enteritis virus with new generation canine parvovirus vaccines based on synthetic peptide or recombinant protein

    DEFF Research Database (Denmark)

    Langeveld, J. P.; Kamstrup, Søren; Uttenthal, Åse;

    1995-01-01

    Two recently developed vaccines—one based on synthetic peptide and one based on recombinant capsid protein—fully protected dogs against heavy experimental canine parvovirus (CPV) infection. The high sequence homology (>98%) and antigenic similarity between CPV and mink enteritis virus (MEV), feline...... panleukopenia virus, and raccoon parvovirus, suggest that both vaccines could protect mink, cats and raccoons against these respective host range variants. This was tested in mink and turned out to be the case. The two vaccines were fully protective and as effective as a conventional commercial vaccine based...

  7. FULL-LENGTH PEPTIDE ASSAY OF ANTIGENIC PROFILE OF ENVELOPE PROTEINS FROM SIBERIAN ISOLATES OF HEPATITIS C VIRUS

    Directory of Open Access Journals (Sweden)

    A. A. Grazhdantseva

    2010-01-01

    Full Text Available Antigenic profiles of envelope glycoproteins of hepatitis C virus presented by three genotypes 1b, 2a/2c and 3a, which are most widespread in the territory of Russia and, in particular, in Novosibirsk, were studied using a panel of overlapping synthetic peptides. It was shown that highly immunogenic peptide epitopes of Е1 and Е2 proteins common for all HCV genotypes, are located in amino acid positions 250-260, 315-325 (Е1 protein, 390-400 (hypervariable region 1, 430-440, and 680-690 (Е2 protein. The greatest inter-genotypic differences were recorded in positions 280-290, 410-430 and 520-540. A novel antigenic determinant was detected in the region of aa 280-290 of the Е1 protein which was typical only for HCV 2a/2c genotype. A broad variation in the boundaries for the most epitopes suggests a high variability of the Е1 and Е2 viral proteins; however, a similar repertoire of antibodies induced by different HCV genotypes indicates to an opportunity of designing a new generation of cross-reactive HCV vaccines based on mapping of the E1 and E2 antigenic regions.

  8. In vivo targeting of antigens to maturing dendritic cells via the DEC-205 receptor improves T cell vaccination.

    Science.gov (United States)

    Bonifaz, Laura C; Bonnyay, David P; Charalambous, Anna; Darguste, Dara I; Fujii, Shin-Ichiro; Soares, Helena; Brimnes, Marie K; Moltedo, Bruno; Moran, Thomas M; Steinman, Ralph M

    2004-03-15

    The prevention and treatment of prevalent infectious diseases and tumors should benefit from improvements in the induction of antigen-specific T cell immunity. To assess the potential of antigen targeting to dendritic cells to improve immunity, we incorporated ovalbumin protein into a monoclonal antibody to the DEC-205 receptor, an endocytic receptor that is abundant on these cells in lymphoid tissues. Simultaneously, we injected agonistic alpha-CD40 antibody to mature the dendritic cells. We found that a single low dose of antibody-conjugated ovalbumin initiated immunity from the naive CD4+ and CD8+ T cell repertoire. Unexpectedly, the alphaDEC-205 antigen conjugates, given s.c., targeted to dendritic cells systemically and for long periods, and ovalbumin peptide was presented on MHC class I for 2 weeks. This was associated with stronger CD8+ T cell-mediated immunity relative to other forms of antigen delivery, even when the latter was given at a thousand times higher doses. In parallel, the mice showed enhanced resistance to an established rapidly growing tumor and to viral infection at a mucosal site. By better harnessing the immunizing functions of maturing dendritic cells, antibody-mediated antigen targeting via the DEC-205 receptor increases the efficiency of vaccination for T cell immunity, including systemic and mucosal resistance in disease models.

  9. In Vivo Targeting of Antigens to Maturing Dendritic Cells via the DEC-205 Receptor Improves T Cell Vaccination

    Science.gov (United States)

    Bonifaz, Laura C.; Bonnyay, David P.; Charalambous, Anna; Darguste, Dara I.; Fujii, Shin-Ichiro; Soares, Helena; Brimnes, Marie K.; Moltedo, Bruno; Moran, Thomas M.; Steinman, Ralph M.

    2004-01-01

    The prevention and treatment of prevalent infectious diseases and tumors should benefit from improvements in the induction of antigen-specific T cell immunity. To assess the potential of antigen targeting to dendritic cells to improve immunity, we incorporated ovalbumin protein into a monoclonal antibody to the DEC-205 receptor, an endocytic receptor that is abundant on these cells in lymphoid tissues. Simultaneously, we injected agonistic α-CD40 antibody to mature the dendritic cells. We found that a single low dose of antibody-conjugated ovalbumin initiated immunity from the naive CD4+ and CD8+ T cell repertoire. Unexpectedly, the αDEC-205 antigen conjugates, given s.c., targeted to dendritic cells systemically and for long periods, and ovalbumin peptide was presented on MHC class I for 2 weeks. This was associated with stronger CD8+ T cell–mediated immunity relative to other forms of antigen delivery, even when the latter was given at a thousand times higher doses. In parallel, the mice showed enhanced resistance to an established rapidly growing tumor and to viral infection at a mucosal site. By better harnessing the immunizing functions of maturing dendritic cells, antibody-mediated antigen targeting via the DEC-205 receptor increases the efficiency of vaccination for T cell immunity, including systemic and mucosal resistance in disease models. PMID:15024047

  10. Surface Modification of Liposomal Vaccines by Peptide Conjugation

    Directory of Open Access Journals (Sweden)

    Hazra M2

    2011-01-01

    Full Text Available The aim of the present work was to prepare liposomal vaccine formulation by incorporating naked plasmid DNA that can trigger humoral and cell mediated protective immunity against infection. For these cationic lipids like dimyristoyl phosphatidylcholine (DMPC, dioleyl phosphatidyl ethanolamine (DOPE, [1, 2 – dioleyloxy -3-(trimethyl ammonium propane] (DOTAP, were taken in the ratio of 4:2:1 respectively. The liposomal formulations thus prepared were surface modified by peptide conjugation with the help of EDC and NHS. Physical characterization of liposomal formulationswas done by estimating the average size distribution, which gives an average liposomal size of 53.0nm. Concentration of peptide bound liposomes wasestimated by Lowry method which entails that bound protein concentration was 30.5 µg/ml.

  11. Peptide-based candidate vaccine against respiratory syncytial virus.

    Science.gov (United States)

    Yusibov, Vidadi; Mett, Vadim; Mett, Valentina; Davidson, Carley; Musiychuk, Konstantin; Gilliam, Suzan; Farese, Ann; Macvittie, Thomas; Mann, Dean

    2005-03-18

    We engineered a 21-mer peptide representing amino acids 170-190 of the respiratory syncytial virus (RSV) G protein as a fusion with the Alfalfa mosaic virus (AlMV) coat protein (CP), produced recombinant AlMV particles presenting this peptide (VMR-RSV) on their surfaces and tested the immunogenicity in vitro in human dendritic cells and in vivo in non-human primates. Significant pathogen-specific immune responses were generated in both systems: (i) human dendritic cells armed with VMR-RSV generated vigorous CD4+ and CD8+ T cell responses; (ii) non-human primates that received these particles responded by mounting strong cellular and humoral immune responses. This approach may validate the use of a novel RSV vaccine delivery vehicle in humans. PMID:15755607

  12. Potentiation of anthrax vaccines using protective antigen-expressing viral replicon vectors.

    Science.gov (United States)

    Wang, Hai-Chao; An, Huai-Jie; Yu, Yun-Zhou; Xu, Qing

    2015-02-01

    DNA vaccines require improvement for human use because they are generally weak stimulators of the immune system in humans. The efficacy of DNA vaccines can be improved using a viral replicon as vector to administer antigen of pathogen. In this study, we comprehensively evaluated the conventional non-viral DNA, viral replicon DNA or viral replicon particles (VRP) vaccines encoding different forms of anthrax protective antigen (PA) for specific immunity and protective potency against anthrax. Our current results clearly suggested that these viral replicon DNA or VRP vaccines derived from Semliki Forest virus (SFV) induced stronger PA-specific immune responses than the conventional non-viral DNA vaccines when encoding the same antigen forms, which resulted in potent protection against challenge with the Bacillus anthracis strain A16R. Additionally, the naked PA-expressing SFV replicon DNA or VRP vaccines without the need for high doses or demanding particular delivery regimens elicited robust immune responses and afforded completely protective potencies, which indicated the potential of the SFV replicon as vector of anthrax vaccines for use in clinical application. Therefore, our results suggest that these PA-expressing SFV replicon DNA or VRP vaccines may be suitable as candidate vaccines against anthrax. PMID:25102364

  13. Experimental Study of Interference Between Pertussis Antigens and Salk Poliomyelitis Vaccine

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    H. Mirehamsy

    1962-01-01

    Full Text Available An interference is observed between whooping-cough antigens and Salk polioc vaccine even if the two components are mixed immediately before use. The phenomenon is more evident when flUlid antigens are injected. Pertussis soluble antigen, which gives a good serological response in rabbits, when used alone or combined with DT, is inactivated in the presence of Salk polio vacc:ne

  14. Protective efficacy of vaccination with Neospora caninum multiple recombinant antigens against experimental Neospora caninum infection

    OpenAIRE

    Cho, Jung-Hwa; Chung, Woo-Suk; Song, Kyoung-Ju; Na, Byoung-kuk; Kang, Seung-Won; Song, Chul-Yong; Kim, Tong-Soo

    2005-01-01

    Protective efficacy of vaccination with Neospora caninum multiple recombinant antigens against N. caninum infection was evaluated in vitro and in vivo. Two major immunodominant surface antigens (NcSAG1 and NcSRS2) and two dense granule proteins (NcDG1 and NcDG2) of N. caninum tachyzoites were expressed in E. coli, respectively. An in vitro neutralization assay using polyclonal antisera raised against each recombinant antigen showed inhibitory effects on the invasion of N. caninum tachyzoites ...

  15. Potential of Translationally Controlled Tumor Protein-Derived Protein Transduction Domains as Antigen Carriers for Nasal Vaccine Delivery.

    Science.gov (United States)

    Bae, Hae-Duck; Lee, Joohyun; Jin, Xing-Hai; Lee, Kyunglim

    2016-09-01

    Nasal vaccination offers a promising alternative to intramuscular (i.m.) vaccination because it can induce both mucosal and systemic immunity. However, its major drawback is poor absorption of large antigens in the nasal epithelium. Protein transduction domains (PTDs), also called cell-penetrating peptides, have been proposed as vehicles for nasal delivery of therapeutic peptides and proteins. Here, we evaluated the potential of a mutant PTD derived from translationally controlled tumor protein (designated TCTP-PTD 13) as an antigen carrier for nasal vaccines. We first compared the l- and d-forms of TCTP-PTD 13 isomers (l- or d-TCTP-PTD 13) as antigen carriers. Studies in mice demonstrated that nasally administered mixtures of the model antigen ovalbumin (OVA) and d-TCTP-PTD 13 induced higher plasma IgG titers and secretory IgA levels in nasal washes than nasally administered OVA alone, OVA/l-TCTP-PTD 13, or i.m.-injected OVA. Plasma IgG subclass responses (IgG1 and IgG2a) of mice nasally administered OVA/d-TCTP-PTD 13 showed that the predominant IgG subclass was IgG1, indicating a Th2-biased immune response. We also used synthetic CpG oligonucleotides (CpG) as a Th1 immune response-inducing adjuvant. Nasally administered CpG plus OVA/d-TCTP-PTD 13 was superior in eliciting systemic and mucosal immune responses compared to those induced by nasally administered OVA/d-TCTP-PTD 13. Furthermore, the OVA/CpG/d-TCTP-PTD 13 combination skewed IgG1 and IgG2a profiles of humoral immune responses toward a Th1 profile. These findings suggest that TCTP-derived PTD is a suitable vehicle to efficiently carry antigens and to induce more powerful antigen-specific immune responses and a more balanced Th1/Th2 response when combined with a DNA adjuvant. PMID:27454469

  16. Investigation of the response to the enterobacterial common antigen after typhoid vaccination

    Directory of Open Access Journals (Sweden)

    Arlete M. Milhomem

    1987-03-01

    Full Text Available Antibodies against the Salmonella typhi enterobacterial common antigen (ECA and the O and H antigens were investigated in sera from healthy male subjects who had been previously vaccinated with the typhoid vaccine. No serological response to ECA was observed. Sera from subjects not previously vaccinated presented titers of ECA hemagglutinins which quantitatively were related to the presence ofH titers, but not to O agglutinins but with no statistical significance. The results are discussed in relation to the possible protective immunological mechanisms in typhoid fever.

  17. Successful adjuvant-free vaccination of BALB/c mice with mutated amyloid β peptides

    Directory of Open Access Journals (Sweden)

    Wahi Monika M

    2008-02-01

    Full Text Available Abstract Background A recent human clinical trial of an Alzheimer's disease (AD vaccine using amyloid beta (Aβ 1–42 plus QS-21 adjuvant produced some positive results, but was halted due to meningoencephalitis in some participants. The development of a vaccine with mutant Aβ peptides that avoids the use of an adjuvant may result in an effective and safer human vaccine. Results All peptides tested showed high antibody responses, were long-lasting, and demonstrated good memory response. Epitope mapping indicated that peptide mutation did not lead to epitope switching. Mutant peptides induced different inflammation responses as evidenced by cytokine profiles. Ig isotyping indicated that adjuvant-free vaccination with peptides drove an adequate Th2 response. All anti-sera from vaccinated mice cross-reacted with human Aβ in APP/PS1 transgenic mouse brain tissue. Conclusion Our study demonstrated that an adjuvant-free vaccine with different Aβ peptides can be an effective and safe vaccination approach against AD. This study represents the first report of adjuvant-free vaccines utilizing Aβ peptides carrying diverse mutations in the T-cell epitope. These largely positive results provide encouragement for the future of the development of human vaccinations for AD.

  18. Structural and Computational Biology in the Design of Immunogenic Vaccine Antigens

    Directory of Open Access Journals (Sweden)

    Lassi Liljeroos

    2015-01-01

    Full Text Available Vaccination is historically one of the most important medical interventions for the prevention of infectious disease. Previously, vaccines were typically made of rather crude mixtures of inactivated or attenuated causative agents. However, over the last 10–20 years, several important technological and computational advances have enabled major progress in the discovery and design of potently immunogenic recombinant protein vaccine antigens. Here we discuss three key breakthrough approaches that have potentiated structural and computational vaccine design. Firstly, genomic sciences gave birth to the field of reverse vaccinology, which has enabled the rapid computational identification of potential vaccine antigens. Secondly, major advances in structural biology, experimental epitope mapping, and computational epitope prediction have yielded molecular insights into the immunogenic determinants defining protective antigens, enabling their rational optimization. Thirdly, and most recently, computational approaches have been used to convert this wealth of structural and immunological information into the design of improved vaccine antigens. This review aims to illustrate the growing power of combining sequencing, structural and computational approaches, and we discuss how this may drive the design of novel immunogens suitable for future vaccines urgently needed to increase the global prevention of infectious disease.

  19. Vaccination with intestinal tract antigens does not induce protective immunity in a permissive model of filariasis.

    Science.gov (United States)

    Morris, C Paul; Torrero, Marina N; Larson, David; Evans, Holly; Shi, Yinghui; Cox, Rachel T; Mitre, Edward

    2013-09-01

    Antigens obtained from the intestinal tract of filarial nematodes have been proposed as potential safe and effective vaccine candidates. Because they may be 'hidden' from the immune response during natural infection, yet accessible by antibodies induced by vaccination, intestinal antigens may have a low potential for eliciting allergic responses when vaccinating previously infected individuals. Despite prior promising data, vaccination with intestinal antigens has yet to be tested in a permissive model of filariasis. In this study we investigated the efficacy of vaccination with filarial intestinal antigens in the permissive Litomosoides sigmodontis BALB/c model of filariasis, and we evaluated the extent to which these antigens are recognized by the immune system during and after infection. Infected BALB/c mice developed lower IgG antibody responses to soluble intestinal antigens (GutAg) than to soluble antigens of whole worms (LsAg). Similarly, GutAg induced less proliferation and less production of IL-4 and IFNγ from splenocytes of infected mice than LsAg. In contrast to these differences, active infection resulted in equivalent levels of circulating GutAg-specific IgE and LsAg-specific IgE levels. Consistent with this, basophil activation, as assessed by flow cytometric staining of intracellular basophil IL-4 expression, was equivalent in response to GutAg and LsAg. Vaccination with GutAg adsorbed to CpG/alum induced GutAg specific IgG1 and IgG2A production, with GutAg specific IgG titers greater than 5-fold higher than those measured in previously infected animals. Despite this response to GutAg vaccination, vaccinated mice harbored similar parasite burdens 8 weeks post infection when compared to non-vaccinated controls. These studies demonstrate that soluble antigens obtained from the intestinal tracts of L. sigmodontis have some qualities of 'hidden' antigens, but they still sensitize mice to allergic reactions and fail to protect against future infection

  20. Prime-Boost Vaccination Using Chemokine-Fused gp120 DNA and HIV Envelope Peptides Activates Both Immediate and Long-Term Memory Cellular Responses in Rhesus Macaques

    Directory of Open Access Journals (Sweden)

    Hong Qin

    2010-01-01

    Full Text Available HIV vaccine candidates with improved immunogenicity and induction of mucosal T-cell immunity are needed. A prime-boost strategy using a novel HIV glycoprotein 120 DNA vaccine was employed to immunize rhesus macaques. The DNA vaccine encoded a chimeric gp120 protein in fusion with monocyte chemoattractant protein-3, which was hypothesized to improve the ability of antigen-presenting cells to capture viral antigen through chemokine receptor-mediated endocytosis. DNA vaccination induced virus-reactive T cells in peripheral blood, detectable by T cell proliferation, INFγ ELISPOT and sustained IL-6 production, without humoral responses. With a peptide-cocktail vaccine containing a set of conserved polypeptides of HIV-1 envelope protein, given by nasogastric administration, primed T-cell immunity was significantly boosted. Surprisingly, long-term and peptide-specific mucosal memory T-cell immunity was detected in both vaccinated macaques after one year. Therefore, data from this investigation offer proof-of-principle for potential effectiveness of the prime-boost strategy with a chemokine-fused gp120 DNA and warrant further testing in the nonhuman primate models for developing as a potential HIV vaccine candidate in humans.

  1. Phase I clinical study of anti-apoptosis protein, survivin-derived peptide vaccine therapy for patients with advanced or recurrent colorectal cancer

    Directory of Open Access Journals (Sweden)

    Minamida Hidetoshi

    2004-06-01

    Full Text Available Abstract Survivin is a member of the inhibitor of apoptosis protein (IAP family containing a single baculovirus IAP repeat domain. It is expressed during fetal development but becomes undetectable in terminally differentiated normal adult tissues. We previously reported that survivin and its splicing variant survivin-2B was expressed abundantly in various types of tumor tissues as well as tumor cell lines and was suitable as a target antigen for active-specific anti-cancer immunization. Subsequently, we identified an HLA-A24-restricted antigenic peptide, survivin-2B80-88 (AYACNTSTL recognized by CD8+ cytotoxic T lymphocytes (CTLs. We, therefore, started a phase I clinical study assessing the efficacy of survivin-2B peptide vaccination in patients with advanced or recurrent colorectal cancer expressing survivin. Vaccinations with survivin-2B peptide were given subcutaneously six times at 14-day intervals. Of 15 patients who finished receiving the vaccination schedule, three suffered slight toxicities, including anemia (grade 2, general malaise (grade 1, and fever (grade 1. No severe adverse events were observed in any patient. In 6 patients, tumor marker levels (CEA and CA19-9 decreased transiently during the period of vaccination. Slight reduction of the tumor volume was observed in one patient, which was considered a minor responder. No changes were noted in three patients while the remaining eleven patients experienced tumor progression. Analysis of peripheral blood lymphocytes of one patient using HLA-A24/peptide tetramers revealed an increase in peptide-specific CTL frequency from 0.09% to 0.35% of CD8+ T cells after 4 vaccinations. This phase I clinical study indicates that survivin-2B peptide-based vaccination is safe and should be further considered for potential immune and clinical efficacy in HLA-A24-expression patients with colorectal cancer.

  2. Novel selective inhibitors of aminopeptidases that generate antigenic peptides.

    Science.gov (United States)

    Papakyriakou, Athanasios; Zervoudi, Efthalia; Theodorakis, Emmanuel A; Saveanu, Loredana; Stratikos, Efstratios; Vourloumis, Dionisios

    2013-09-01

    Endoplasmic reticulum aminopeptidases, ERAP1 and ERAP2, as well as Insulin regulated aminopeptidase (IRAP) play key roles in antigen processing, and have recently emerged as biologically important targets for manipulation of antigen presentation. Taking advantage of the available structural and substrate-selectivity data for these enzymes, we have rationally designed a new series of inhibitors that display low micromolar activity. The selectivity profile for these three highly homologous aminopeptidases provides a promising avenue for modulating intracellular antigen processing. PMID:23916253

  3. Immunogenicity of Mycobacterium avium subsp. paratuberculosis specific peptides for inclusion in a subunit vaccine against paratuberculosis

    DEFF Research Database (Denmark)

    Mikkelsen, Heidi; Tollefsen, S.; Olsen, I.;

    efficacies. The main problem with available vaccines is their interference with surveillance and diagnosis of bovine tuberculosis and paratuberculosis. Our ultimate aim is to develop a subunit vaccine consisting of selected MAP peptides, which allow differentiation of infected from vaccinated animals. Here...

  4. CD8+ T cell priming by dendritic cell vaccines requires antigen transfer to endogenous antigen presenting cells.

    Directory of Open Access Journals (Sweden)

    Alice W Yewdall

    Full Text Available Immunotherapeutic strategies to stimulate anti-tumor immunity are promising approaches for cancer treatment. A major barrier to their success is the immunosuppressive microenvironment of tumors, which inhibits the functions of endogenous dendritic cells (DCs that are necessary for the generation of anti-tumor CD8+ T cells. To overcome this problem, autologous DCs are generated ex vivo, loaded with tumor antigens, and activated in this non-suppressive environment before administration to patients. However, DC-based vaccines rarely induce tumor regression.We examined the fate and function of these DCs following their injection using murine models, in order to better understand their interaction with the host immune system. Contrary to previous assumptions, we show that DC vaccines have an insignificant role in directly priming CD8+ T cells, but instead function primarily as vehicles for transferring antigens to endogenous antigen presenting cells, which are responsible for the subsequent activation of T cells.This reliance on endogenous immune cells may explain the limited success of current DC vaccines to treat cancer and offers new insight into how these therapies can be improved. Future approaches should focus on creating DC vaccines that are more effective at directly priming T cells, or abrogating the tumor induced suppression of endogenous DCs.

  5. TH1 and TH2 responses are influenced by HLA antigens in healthy neonates vaccinated with recombinant hepatitis B vaccine.

    Directory of Open Access Journals (Sweden)

    Abdollah Jafarzadeh

    2012-12-01

    Full Text Available The immune response to hepatitis B surface antigen (HBsAg is influenced by several factors, of which HLA antigens and balanced secretion of Th1/Th2 cytokines play important roles. The aim of this study was to evaluate the influence of HLA antigens on cytokine secretion by HBsAg-stimulated peripheral blood mononuclear cells (PBMC from healthy neonates vaccinated with recombinant HBsAg. PBMCs were isolated from 48 Iranian neonates vaccinated with a recombinant HBV vaccine. The cells were stimulated in vitro with rHBsAg and the concentration of IL-4, IL-10, IL-12 and IFN-γ were quantitated in culture supernatant by sandwich ELISA. HLA typing was performed by microlymphocytotoxicity method. Significant diminished secretion of both Th1 (IFN-γ and Th2 (IL-4, IL-10 cytokines was observed in HBsAg-stimulated PBMC from vaccinees expressing the HLA-DR7 compared to DR7 negative vaccinees. Similarly, lower production of these cytokines was also observed in vaccinees with DR7-DR53-DQ2, B7-DR7-DR53-DQ2 and A2-DR7-DR53-DQ2 haplotypes (p<0.05, p <0.005. While HBsAg-stimulated PBMC of DR13+ subjects produced lower levels of Th2-type cytokines (IL-4 and IL-10, those of HLA-B8+ or HLA-A9+ subjects produced higher levels of Th2-type cytokines. Cytokine secretion in response to PHA mitogen was not associated with a given HLA antigen or haplotype and was similarly represented in all groups of subjects irrespective of their HLA complex. These results indicate that HLA antigens may differentially influence cytokine secretion by HBsAg-specific T-cells of healthy neonates vaccinated with recombinant HB vaccine. This phenomenon may have an important implication for control of the immune response to HBsAg vaccine.

  6. Serodiagnosis of Echinococcus spp. infection: explorative selection of diagnostic antigens by peptide microarray.

    Directory of Open Access Journals (Sweden)

    Claudia List

    Full Text Available BACKGROUND: Production of native antigens for serodiagnosis of helminthic infections is laborious and hampered by batch-to-batch variation. For serodiagnosis of echinococcosis, especially cystic disease, most screening tests rely on crude or purified Echinococcus granulosus hydatid cyst fluid. To resolve limitations associated with native antigens in serological tests, the use of standardized and highly pure antigens produced by chemical synthesis offers considerable advantages, provided appropriate diagnostic sensitivity and specificity is achieved. METHODOLOGY/PRINCIPAL FINDINGS: Making use of the growing collection of genomic and proteomic data, we applied a set of bioinformatic selection criteria to a collection of protein sequences including conceptually translated nucleotide sequence data of two related tapeworms, Echinococcus multilocularis and Echinococcus granulosus. Our approach targeted alpha-helical coiled-coils and intrinsically unstructured regions of parasite proteins potentially exposed to the host immune system. From 6 proteins of E. multilocularis and 5 proteins of E. granulosus, 45 peptides between 24 and 30 amino acids in length were designed. These peptides were chemically synthesized, spotted on microarrays and screened for reactivity with sera from infected humans. Peptides reacting above the cut-off were validated in enzyme-linked immunosorbent assays (ELISA. Peptides identified failed to differentiate between E. multilocularis and E. granulosus infection. The peptide performing best reached 57% sensitivity and 94% specificity. This candidate derived from Echinococcus multilocularis antigen B8/1 and showed strong reactivity to sera from patients infected either with E. multilocularis or E. granulosus. CONCLUSIONS/SIGNIFICANCE: This study provides proof of principle for the discovery of diagnostically relevant peptides by bioinformatic selection complemented with screening on a high-throughput microarray platform. Our data

  7. Controlled and targeted release of antigens by intelligent shell for improving applicability of oral vaccines.

    Science.gov (United States)

    Zhang, Lei; Zeng, Zhanzhuang; Hu, Chaohua; Bellis, Susan L; Yang, Wendi; Su, Yintao; Zhang, Xinyan; Wu, Yunkun

    2016-01-01

    Conventional oral vaccines with simple architecture face barriers with regard to stimulating effective immunity. Here we describe oral vaccines with an intelligent phase-transitional shielding layer, poly[(methyl methacrylate)-co-(methyl acrylate)-co-(methacrylic acid)]-poly(D,L-lactide-co-glycolide) (PMMMA-PLGA), which can protect antigens in the gastro-intestinal tract and achieve targeted vaccination in the large intestine. With the surface immunogenic protein (SIP) from group B Streptococcus (GBS) entrapped as the antigen, oral administration with PMMMA-PLGA (PTRBL)/Trx-SIP nanoparticles stimulated robust immunity in tilapia, an animal with a relatively simple immune system. The vaccine succeeded in protecting against Streptococcus agalactiae, a pathogen of worldwide importance that threatens human health and is transmitted in water with infected fish. After oral vaccination with PTRBL/Trx-SIP, tilapia produced enhanced levels of SIP specific antibodies and displayed durability of immune protection. 100% of the vaccinated tilapia were protected from GBS infection, whereas the control groups without vaccines or vaccinated with Trx-SIP only exhibited respective infection rates of 100% or >60% within the initial 5 months after primary vaccination. Experiments in vivo demonstrated that the recombinant antigen Trx-SIP labeled with FITC was localized in colon, spleen and kidney, which are critical sites for mounting an immune response. Our results revealed that, rather than the size of the nanoparticles, it is more likely that the negative charge repulsion produced by ionization of the carboxyl groups in PMMMA shielded the nanoparticles from uptake by small intestinal epithelial cells. This system resolves challenges arising from gastrointestinal damage to antigens, and more importantly, offers a new approach applicable for oral vaccination.

  8. Controlled and targeted release of antigens by intelligent shell for improving applicability of oral vaccines.

    Science.gov (United States)

    Zhang, Lei; Zeng, Zhanzhuang; Hu, Chaohua; Bellis, Susan L; Yang, Wendi; Su, Yintao; Zhang, Xinyan; Wu, Yunkun

    2016-01-01

    Conventional oral vaccines with simple architecture face barriers with regard to stimulating effective immunity. Here we describe oral vaccines with an intelligent phase-transitional shielding layer, poly[(methyl methacrylate)-co-(methyl acrylate)-co-(methacrylic acid)]-poly(D,L-lactide-co-glycolide) (PMMMA-PLGA), which can protect antigens in the gastro-intestinal tract and achieve targeted vaccination in the large intestine. With the surface immunogenic protein (SIP) from group B Streptococcus (GBS) entrapped as the antigen, oral administration with PMMMA-PLGA (PTRBL)/Trx-SIP nanoparticles stimulated robust immunity in tilapia, an animal with a relatively simple immune system. The vaccine succeeded in protecting against Streptococcus agalactiae, a pathogen of worldwide importance that threatens human health and is transmitted in water with infected fish. After oral vaccination with PTRBL/Trx-SIP, tilapia produced enhanced levels of SIP specific antibodies and displayed durability of immune protection. 100% of the vaccinated tilapia were protected from GBS infection, whereas the control groups without vaccines or vaccinated with Trx-SIP only exhibited respective infection rates of 100% or >60% within the initial 5 months after primary vaccination. Experiments in vivo demonstrated that the recombinant antigen Trx-SIP labeled with FITC was localized in colon, spleen and kidney, which are critical sites for mounting an immune response. Our results revealed that, rather than the size of the nanoparticles, it is more likely that the negative charge repulsion produced by ionization of the carboxyl groups in PMMMA shielded the nanoparticles from uptake by small intestinal epithelial cells. This system resolves challenges arising from gastrointestinal damage to antigens, and more importantly, offers a new approach applicable for oral vaccination. PMID:26624805

  9. Antibodies against a class II HLA-peptide complex raised by active immunization of mice with antigen mimicking peptides

    DEFF Research Database (Denmark)

    Dam-Tuxen, R; Riise, Erik Skjold

    2009-01-01

    Multiple sclerosis (MS) is an autoimmune disease linked to the human leucocyte antigen (HLA) class II genes DRB1*1501, DRB5*0101 and DQB1*0602. T cells reactive towards the DRB1*1501 in complex with various peptides derived from myelin basic protein (MBP), which is the major component of myelin...

  10. Immunization with antigenic peptides complexed with β-glucan induces potent cytotoxic T-lymphocyte activity in combination with CpG-ODNs.

    Science.gov (United States)

    Mochizuki, Shinichi; Morishita, Hiromi; Kobiyama, Kouji; Aoshi, Taiki; Ishii, Ken J; Sakurai, Kazuo

    2015-12-28

    The induction of antigen-specific immune responses requires immunization with not only antigens, but also adjuvants. CpG oligonucleotides (CpG-ODNs) are well-known ligands for Toll-like receptor 9 and a potent adjuvant that induces both Th1-type humoral and cellular immune responses including cytotoxic T-lymphocyte responses. We previously demonstrated that β-glucan schizophyllan (SPG) can form complexes with CpG-ODNs with attached dA40 (CpG-dA/SPG), which can accumulate in macrophages in the draining inguinal lymph nodes and induce strong immune responses by co-administration of antigenic proteins, namely ovalbumin (OVA). Immunization with antigenic peptides, OVA257-264, did not induce these antigen-specific immune responses even in combination with CpG-dA/SPG, indicating that peptides require a carrier to antigen presenting cells. In this study, we prepared conjugates comprising OVA257-264 and dA40, and made complexes with SPG. Immunization with OVA257-264-dA/SPG induced peptide-specific immune responses in combination with CpG-dA regardless of complexation with SPG both in vitro and in vivo. When splenocytes from immunized mice were incubated with E.G7-OVA tumor model cells presenting OVA peptides, the number of cells drastically decreased after 24h. Furthermore, mice pre-immunized with OVA257-264-dA/SPG and CpG-ODNs exhibited a long delay in tumor growth after tumor inoculation. Therefore, these peptide-dA/SPG and CpG-dA/SPG complexes could be used as a potent vaccine for the treatment of cancers and infectious diseases. PMID:26562685

  11. Comparative vaccination of cattle against Boophilus microplus with recombinant antigen Bm86 alone or in combination with recombinant Bm91.

    Science.gov (United States)

    Willadsen, P; Smith, D; Cobon, G; McKenna, R V

    1996-05-01

    Cattle were vaccinated either with a single recombinant tick antigen, Bm86 or with a combination of two recombinant antigens, Bm86 and Bm91 from the tick Boophilus microplus. In three experiments, the responses of cattle to subsequent challenge with the tick were assessed. The addition of the Bm91 antigen enhanced the efficacy of the vaccination over that with Bm86 alone to a statistically significant degree. Moreover, co-vaccination with two antigens did not impair the response of cattle to the Bm86 antigen. Finally, responses of individual cattle to the two antigens were independent. All of these results may be relevant to the increase in efficacy expected from a dual antigen vaccine. PMID:9229376

  12. Montanide ISA 720 vaccines: quality control of emulsions, stability of formulated antigens, and comparative immunogenicity of vaccine formulations.

    Science.gov (United States)

    Miles, Aaron P; McClellan, Holly A; Rausch, Kelly M; Zhu, Daming; Whitmore, Michael D; Singh, Sanjay; Martin, Laura B; Wu, Yimin; Giersing, Birgitte K; Stowers, Anthony W; Long, Carole A; Saul, Allan

    2005-03-31

    Montanide ISA 720 is an experimental adjuvant, formulated as water-in-oil emulsions, that induces high antibody titers in several animal species. It has been used in human vaccine trials with malaria and HIV vaccines. The heightened response is likely due, in part, to the formation of a depot at the injection site. However, post-formulation modifications were seen with seven proteins tested during storage of ISA 720 formulations at 37 degrees C for 1 week and two proteins stored longer at 4 degrees C. Potency studies in mice, in which the stored vaccines were diluted into placebo emulsions for appropriate dosing, indicated that this instability could lead to loss of immunogenicity in the post-injection depot, limiting the allowable storage time of preformed vaccines. We describe point-of-injection formulation for ISA 720 vaccines that meets the requirement for in vitro stability. For preformed vaccines, addition of glycine or glycylglycine prevented antigen modification on storage at 37 degrees C, providing a potential way of stabilizing antigen/ISA 720 formulations for in vitro storage and the post-injection depot.

  13. Identification and Characterization of Peptide Mimics of Blood Group A Antigen

    Institute of Scientific and Technical Information of China (English)

    Zhaoming TANG; Lin WANG; Lihua HU; Yirong LI; Tianpen CUI; Juan XIONG; Lifang DOU

    2008-01-01

    In order to investigate peptide mimics of carbohydrate blood group A antigen, a phage display 12-met peptide library was screened with a monoclonal antibody against blood group A antigen, NaM87-1F6. The antibody-binding properties of the selected phage peptides were evaluated by phage ELISA and phage capture assay. The peptides were co-expressed as glutathione S-transferase (GST) fusion proteins. RBC agglutination inhibition assay was performed to assess the natural blood group A antigen-mimicking ability of the fusion proteins. The results showed that seven phage clones selected bound to NaM87-1F6 specifically, among which, 6 clones bore the same peptide sequence, EYWYCGMNRTGC and another harbored a different one QIWYERTLPFrF. The two peptides were successfully expressed at the N terminal of GST protein. Both of the fusion proteins inhibited the RBC agglutination mediated by anti-A serum in a concentration-dependent manner. These results suggested that the fusion proteins based on the selected peptides could mimic the blood group A an- tigen and might be used as anti-A antibody-adsorbing materials when immunoabsorption was applied in ABO incompatible transplantation.

  14. Expression and Immunogenicity of the Mycobacterial Ag85B/ESAT-6 Antigens Produced in Transgenic Plants by Elastin-Like Peptide Fusion Strategy

    Directory of Open Access Journals (Sweden)

    Doreen Manuela Floss

    2010-01-01

    Full Text Available This study explored a novel system combining plant-based production and the elastin-like peptide (ELP fusion strategy to produce vaccinal antigens against tuberculosis. Transgenic tobacco plants expressing the mycobacterial antigens Ag85B and ESAT-6 fused to ELP (TBAg-ELP were generated. Purified TBAg-ELP was obtained by the highly efficient, cost-effective, inverse transition cycling (ICT method and tested in mice. Furthermore, safety and immunogenicity of the crude tobacco leaf extracts were assessed in piglets. Antibodies recognizing mycobacterial antigens were produced in mice and piglets. A T-cell immune response able to recognize the native mycobacterial antigens was detected in mice. These findings showed that the native Ag85B and ESAT-6 mycobacterial B- and T-cell epitopes were conserved in the plant-expressed TBAg-ELP. This study presents the first results of an efficient plant-expression system, relying on the elastin-like peptide fusion strategy, to produce a safe and immunogenic mycobacterial Ag85B-ESAT-6 fusion protein as a potential vaccine candidate against tuberculosis.

  15. INDUCEMENT OF ANTITUMOR-IMMUNITY BY DC ACTIVATED BY HSP70-H22 TUMOR ANTIGEN PEPTIDE

    Institute of Scientific and Technical Information of China (English)

    冯作化; 黄波; 张桂梅; 李东; 王洪涛

    2003-01-01

    Objective: To investigate the feasibility of decreasing the dosage of tumor antigen peptides by dendritic cell (DC)-presenting and the characteristics of modification of DC by heat shock protein (Hsp70) and antigen peptides. Methods: Peptides were bound to Hsp70 and used to modify DC in vitro. The metabolism of the modified DC and the cytokines secreted by the modified DC were determined. The activation of lymphocytes by the modified DC and Hsp70-H22 peptides was tested. The cytotoxicity of the activated lymphocytes to H22 tumor cells was analyzed. The inhibitory effect of tumor in mice by the injection of DC and Hsp70-H22 peptides was tested. Results: 0.15μg of H22 peptides bound with Hsp70 could make 2×105 DC mature. 4×103 matured DC could activate 2×106 lymphocytes. The same amount of lymphocytes could be activated to produce similar cytotoxicity to tumor cells by either DC modified by 0.003μg of peptides bound with Hsp70 or by direct stimulation with 0.15μg of peptides bound with Hsp70. The dosage of peptides could be reduced by about 50 folds if the modified DC was used for injection instead of Hsp70-peptides. Peptides from normal hepatocytes, bound with Hsp70, could not make DC mature, nor activate lymphocytes through DC. Conclusion: The dosage of Hsp70-H22 peptides can be reduced significantly by DC-presenting to activate lymphocytes. Peptides from normal cells could not activate lymphocytes by either Hsp70-presenting or DC-presenting and they have little chance to induce autoimmunity.

  16. Vaccination of cattle with TickGARD induces cross-reactive antibodies binding to conserved linear peptides of Bm86 homologues in Boophilus decoloratus.

    Science.gov (United States)

    Odongo, David; Kamau, Lucy; Skilton, Robert; Mwaura, Stephen; Nitsch, Cordula; Musoke, Anthony; Taracha, Evans; Daubenberger, Claudia; Bishop, Richard

    2007-01-26

    Vaccines based on recombinant Bm86 gut antigen from Boophilus microplus are a useful component of integrated control strategies against B. microplus infestations of cattle. The capacity of such vaccines to control heterologous infestations by two African tick species was investigated. The mean weight of engorged female ticks and mean egg mass per tick were significantly reduced in B. decoloratus infestations, but there was no effect of the vaccine against adult Rhipicephalus appendiculatus. We cloned, sequenced and expressed two Bm86 homologues (Bd86) from B. decoloratus. Amino acid sequence identity between Bd86 homologues (Bd86-1 and Bd86-2) and Bm86 was 86% and 85%, respectively, compared to 93% identity between the variants. Native Bd86 protein in B. decoloratus tick mid-gut sections and recombinant Bd86-1 reacted strongly with sera from TickGARD vaccinated cattle. TickGARD can therefore protect against a heterologous tick species with multiple antigen sequences. Epitope mapping using sera from TickGARD-vaccinated cattle identified two linear peptides conserved between the Bd86 homologues and Bm86. These epitopes represent candidate synthetic peptide vaccines for control of Boophilus spp. and the pathogens transmitted by these tick vectors. PMID:17070625

  17. Genetic diversity of vaccine candidate antigens in Plasmodium falciparum isolates from the Amazon basin of Peru

    Directory of Open Access Journals (Sweden)

    Lucas Carmen M

    2008-05-01

    Full Text Available Abstract Background Several of the intended Plasmodium falciparum vaccine candidate antigens are highly polymorphic and could render a vaccine ineffective if their antigenic sites were not represented in the vaccine. In this study, characterization of genetic variability was performed in major B and T-cell epitopes within vaccine candidate antigens in isolates of P. falciparum from Peru. Methods DNA sequencing analysis was completed on 139 isolates of P. falciparum collected from endemic areas of the Amazon basin in Loreto, Peru from years 1998 to 2006. Genetic diversity was determined in immunological important regions in circumsporozoite protein (CSP, merozoite surface protein-1 (MSP-1, apical membrane antigen-1 (AMA-1, liver stage antigen-1 (LSA-1 and thrombospondin-related anonymous protein (TRAP. Alleles identified by DNA sequencing were aligned with the vaccine strain 3D7 and DNA polymorphism analysis and FST study-year pairwise comparisons were done using the DnaSP software. Multilocus analysis (MLA was performed and average of expected heterozygosity was calculated for each loci and haplotype over time. Results Three different alleles for CSP, seven for MSP-1 Block 2, one for MSP-1 Block 17, three for AMA-1 and for LSA-1 each and one for TRAP were identified. There were 24 different haplotypes in 125 infections with complete locus typing for each gene. Conclusion Characterization of the genetic diversity in Plasmodium isolates from the Amazon Region of Peru showed that P. falciparum T and B cell epitopes in these antigens have polymorphisms more similar to India than to Africa. These findings are helpful in the formulation of a vaccine considering restricted repertoire populations.

  18. Evaluation of Mdh1 protein as an antigenic candidate for a vaccine against candidiasis.

    Science.gov (United States)

    Shibasaki, Seiji; Aoki, Wataru; Nomura, Takashi; Karasaki, Miki; Sewaki, Tomomitsu; Ueda, Mitsuyoshi

    2014-01-01

    Candida albicans malate dehydrogenase (Mdh1p) has been screened by previous proteome studies as a candidate for a vaccine against candidiasis. In this study, recombinant Mdh1 protein with a His-tag was produced in Escherichia coli and evaluated as an immunogenic protein against candidiasis. Mdh1p was administrated to mice by two methods subcutaneous injection and intranasal administration before challenging them with a lethal dose of C. albicans. After vaccination of Mdh1p, antibody responses were observed. To evaluate the vaccination effect of Mdh1p, survival tests were performed after 35 d. Although all control mice died within 24 d or 25 d, 100% and 80% of mice survived with subcutaneous and intranasal administration, respectively. Therefore, our results indicate that, among C. albicans antigens examined thus far, Mdh1p is currently the most effective antigen for use as a vaccine for C. albicans.

  19. CD4+ T-cell lines used to evaluate a Mycobacterium avium subsp. paratuberculosis (MAP) peptide vaccine

    DEFF Research Database (Denmark)

    Lybeck, Kari; Sjurseth, Siri K.; Al-Touama, Zainab;

    The aim of the study was to establish a protocol for generation of MAP-specific T-cell lines and to use these lines for evaluation of a peptide vaccine. A protocol for culturing T-cell lines from peripheral blood of goats naturally infected with MAP was established. CD4+ T cells were positively...... selected using an anti CD4 mAb and Dynabeads. Sorted CD4+ cells were cultivated with purified protein derivative from MAP (PPDj) or E. coli sonicate, IL-2, and IL-15. After two cultivation cycles, T cells were tested for recall responses in a proliferative T-cell assay. T-cell line responses were in...... antigens. T-cell lines were now generated by cultivating CD4+ cells with peptides instead of PPDj. Initially, both healthy and MAP-infected goats were vaccinated with 119 peptides defined by in silico analysis. Cellular responses to the peptides were not detected using standard IFN- γ plasma ELISA. However...

  20. Vaccination of Rhesus Macaques with the Anthrax Vaccine Adsorbed Vaccine Produces a Serum Antibody Response That Effectively Neutralizes Receptor-Bound Protective Antigen In Vitro ▿

    OpenAIRE

    Clement, Kristin H.; Rudge, Thomas L.; Mayfield, Heather J.; Carlton, Lena A.; Hester, Arelis; Niemuth, Nancy A.; Sabourin, Carol L.; Brys, April M.; Quinn, Conrad P.

    2010-01-01

    Anthrax toxin (ATx) is composed of the binary exotoxins lethal toxin (LTx) and edema toxin (ETx). They have separate effector proteins (edema factor and lethal factor) but have the same binding protein, protective antigen (PA). PA is the primary immunogen in the current licensed vaccine anthrax vaccine adsorbed (AVA [BioThrax]). AVA confers protective immunity by stimulating production of ATx-neutralizing antibodies, which could block the intoxication process at several steps (binding of PA t...

  1. Pros and Cons of Antigen-Presenting Cell Targeted Tumor Vaccines

    Directory of Open Access Journals (Sweden)

    Cleo Goyvaerts

    2015-01-01

    Full Text Available In therapeutic antitumor vaccination, dendritic cells play the leading role since they decide if, how, when, and where a potent antitumor immune response will take place. Since the disentanglement of the complexity and merit of different antigen-presenting cell subtypes, antitumor immunotherapeutic research started to investigate the potential benefit of targeting these subtypes in situ. This review will discuss which antigen-presenting cell subtypes are at play and how they have been targeted and finally question the true meaning of targeting antitumor-based vaccines.

  2. Sulfate-binding protein, CysP, is a candidate vaccine antigen of Moraxella catarrhalis.

    Science.gov (United States)

    Murphy, Timothy F; Kirkham, Charmaine; Johnson, Antoinette; Brauer, Aimee L; Koszelak-Rosenblum, Mary; Malkowski, Michael G

    2016-07-19

    Moraxella catarrhalis causes otitis media in children and respiratory tract infections in adults with chronic obstructive pulmonary disease (COPD). A vaccine to prevent M. catarrhalis infections would have an enormous impact globally in preventing morbidity caused by M. catarrhalis in these populations. Using a genome mining approach we have identified a sulfate binding protein, CysP, of an ATP binding cassette (ABC) transporter system as a novel candidate vaccine antigen. CysP expresses epitopes on the bacterial surface and is highly conserved among strains. Immunization with CysP induces potentially protective immune responses in a murine pulmonary clearance model. In view of these features that indicate CysP is a promising vaccine antigen, we conducted further studies to elucidate its function. These studies demonstrated that CysP binds sulfate and thiosulfate ions, plays a nutritional role for the organism and functions in intracellular survival of M. catarrhalis in human respiratory epithelial cells. The observations that CysP has features of a vaccine antigen and also plays an important role in growth and survival of the organism indicate that CysP is an excellent candidate vaccine antigen to prevent M. catarrhalis otitis media and infections in adults with COPD. PMID:27265455

  3. Immunological control of ticks through vaccination with Boophilus microplus gut antigens.

    Science.gov (United States)

    De La Fuente, J; Rodríguez, M; García-García, J C

    2000-01-01

    The control of tick infestations and the transmission of tick-borne diseases remain a challenge for the scientific community. Traditional control methods have been only partially successful. Recently, vaccination with recombinant Boophilus microplus gut antigens has been shown to control tick infestations. Our Bm86-containing vaccine formulation (Gavac) has been effective for the control of artificial infestations of B. annulatus, B. decoloratus, and chemically sensitive and resistant B. microplus strains from Australia, Africa, America, and Iran. Preliminary results with Hyalomma spp. and Rhipicephalus spp. suggest partial cross protection. In field trials, vaccination with Gavac controlled B. microplus and B. annulatus infestations and reduced the transmission of babesiosis, resulting in important savings for the cattle industry. Different degrees of susceptibility to the vaccination with Bm86 and sequence variations in the Bm86 locus have been reported. The Bm95 antigen was isolated from the Argentinean Bm86-resistant B. microplus strain A. A Bm95-based vaccine was used to protect cattle against tick infestations under production conditions with similar results to that obtained with Gavac. The Bm95 antigen from strain A was able to protect against infestations with Bm86-sensitive and Bm86-resistant tick strains, thus suggesting that Bm95 could be a more universal antigen in protecting cattle against infestations by B. microplus strains from different geographical areas. These results clearly demonstrate the advantage and possibilities for the immunological control of ticks. PMID:11193686

  4. Human Leukocyte Antigens Influence the Antibody Response to Hepatitis B Vaccine

    OpenAIRE

    Abdollah Jafarzadeh; Masoome Bagheri-Jamebozorgi; Maryam Nemati; Forough Golsaz-Shirazi; Fazel Shokri

    2015-01-01

    Hepatitis B virus (HBV) infection and its sequelae such as cirrhosis and hepatocellular carcinoma has remained a serious public health problem throughout the world. The WHO strategy for effective control of HBV infection and its complications is mass vaccination of neonates and children within the framework of Expanded Programme on Immunization (EPI). Vaccination with hepatitis B surface antigen (HBsAg) induces protective antibody response (anti-HBs ≥ 10 IU/L) in 90-99% of vaccinees.The lack ...

  5. Antigenic peptide trimming by ER aminopeptidases – insights from structural studies

    OpenAIRE

    Stratikos, Efstratios; Stern, Lawrence J.

    2013-01-01

    Generation and destruction of antigenic peptides by ER resident aminopeptidases ERAP1 and ERAP2 have been shown in the last few years to be important for the correct functioning and regulation of the adaptive immune response. These two highly homologous aminopeptidases appear to have evolved complex mechanisms well suited for their biological role in antigen presentation. Furthermore, polymorphic variability in these enzymes appears to affect their function and predispose individuals to disea...

  6. Vaccination with Antigen Combined with αβ-ATP as a Vaccine Adjuvant Enhances Antigen-Specific Antibody Production via Dendritic Cell Activation.

    Science.gov (United States)

    Matsuo, Kazuhiko; Nishiuma, Satoshi; Hasegawa, Yuta; Kawabata, Fumika; Kitahata, Kosuke; Nakayama, Takashi

    2016-01-01

    Adjuvants are required to enhance antigen-specific immune responses by vaccines. Extracellular ATP serves as a danger signal to alert the immune system of tissue damage by acting on P2X and P2Y receptors and triggers the activation of dendritic cells (DCs). Here we investigated the in vivo adjuvant efficacy of α,β-methylene-ATP (αβ-ATP), a non-hydrolysable form of ATP. We found that intradermal injection of ovalbumin (OVA), as a model antigen, combined with αβ-ATP, as the adjuvant, enhanced OVA-specific immune responses more than OVA alone. Additionally, DCs in the skin of mice injected with OVA and αβ-ATP had increased expression of major histocompatibility complex class II and co-stimulator molecules, CD40, CD80, and CD86, suggesting that αβ-ATP activated DC. These findings indicate that αβ-ATP functions as a potent vaccine adjuvant. PMID:27251512

  7. Turnover of Ia-peptide complexes is facilitated in viable antigen-presenting cells: biosynthetic turnover of Ia vs. peptide exchange.

    OpenAIRE

    Harding, C V; Roof, R W; Unanue, E R

    1989-01-01

    Macrophages and B cells process antigens to produce antigenic peptides that associate with class II major histocompatibility complex molecules (e.g., Ia molecules); these Ia-peptide complexes are recognized by CD4+ T lymphocytes. Processing of the antigen hen egg white lysozyme was inhibited by cycloheximide in peritoneal exudate cells (PECs, largely macrophages), but not in TA3 B-lymphoma cells. The uptake and metabolism of hen egg white lysozyme was largely intact in cycloheximide-treated P...

  8. Enhancement of DNA vaccine potency through linkage of antigen to filamentous bacteriophage coat protein III domain I

    DEFF Research Database (Denmark)

    Cuesta, Àngel M; Suárez, Eduardo; Larsen, Martin;

    2006-01-01

    immune pathways by adding immune-activating genes to the tumour antigen sequence. In this work, we converted a model non-immunogenic antigen into a vaccine by fusing it to domain I of the filamentous bacteriophage coat protein III gene. Vaccination with a DNA construct encoding the domain I fusion...

  9. Structural Basis For Antigenic Peptide Precursor Processing by the Endoplasmic Reticulum Aminopeptidase ERAP1

    OpenAIRE

    Nguyen, Tina T.; Chang, Shih-Chung; Evnouchidou, Irini; Ian A York; Zikos, Christos; Rock, Kenneth L.; Goldberg, Alfred L.; Stratikos, Efstratios; Stern, Lawrence J.

    2011-01-01

    ERAP1 trims antigen precursors to fit into MHC class I proteins. To perform this function, ERAP1 has unique substrate preferences, trimming long peptides while sparing shorter ones. To identify the structural basis for ERAP1's unusual properties, we determined the X-ray crystal structure of human ERAP1 bound to bestatin. The structure reveals an open conformation with a large interior compartment. An extended groove originating from the enzyme's catalytic center can accommodate long peptides ...

  10. A novel laser vaccine adjuvant increases the motility of antigen presenting cells.

    Directory of Open Access Journals (Sweden)

    Xinyuan Chen

    Full Text Available BACKGROUND: Development of a potent vaccine adjuvant without introduction of any side effects remains an unmet challenge in the field of the vaccine research. METHODOLOGY/PRINCIPAL FINDINGS: We found that laser at a specific setting increased the motility of antigen presenting cells (APCs and immune responses, with few local or systemic side effects. This laser vaccine adjuvant (LVA effect was induced by brief illumination of a small area of the skin or muscle with a nondestructive, 532 nm green laser prior to intradermal (i.d. or intramuscular (i.m. administration of vaccines at the site of laser illumination. The pre-illumination accelerated the motility of APCs as shown by intravital confocal microscopy, leading to sufficient antigen (Ag-uptake at the site of vaccine injection and transportation of the Ag-captured APCs to the draining lymph nodes. As a result, the number of Ag(+ dendritic cells (DCs in draining lymph nodes was significantly higher in both the 1° and 2° draining lymph nodes in the presence than in the absence of LVA. Laser-mediated increases in the motility and lymphatic transportation of APCs augmented significantly humoral immune responses directed against a model vaccine ovalbumin (OVA or influenza vaccine i.d. injected in both primary and booster vaccinations as compared to the vaccine itself. Strikingly, when the laser was delivered by a hair-like diffusing optical fiber into muscle, laser illumination greatly boosted not only humoral but also cell-mediated immune responses provoked by i.m. immunization with OVA relative to OVA alone. CONCLUSION/SIGNIFICANCE: The results demonstrate the ability of this safe LVA to augment both humoral and cell-mediated immune responses. In comparison with all current vaccine adjuvants that are either chemical compounds or biological agents, LVA is novel in both its form and mechanism; it is risk-free and has distinct advantages over traditional vaccine adjuvants.

  11. Potential Target Antigens for a Universal Vaccine in Epithelial Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Renee Vermeij

    2010-01-01

    Full Text Available The prognosis of epithelial ovarian cancer (EOC, the primary cause of death from gynaecological malignancies, has only modestly improved over the last decades. Immunotherapeutic treatment using a cocktail of antigens has been proposed as a “universal” vaccine strategy. We determined the expression of tumor antigens in the context of MHC class I expression in 270 primary tumor samples using tissue microarray. Expression of tumor antigens p53, SP17, survivin, WT1, and NY-ESO-1 was observed in 120 (48.0%, 173 (68.9%, 208 (90.0%, 129 (56.3%, and 27 (11.0% of 270 tumor specimens, respectively. In 93.2% of EOC, at least one of the investigated tumor antigens was (overexpressed. Expression of MHC class I was observed in 78.1% of EOC. In 3 out 4 primary tumors, (overexpression of a tumor antigen combined with MHC class I was observed. These results indicate that a multiepitope vaccine, comprising these antigens, could serve as a universal therapeutic vaccine for the vast majority of ovarian cancer patients.

  12. Rational Design of Peptide Vaccines Against Multiple Types of Human Papillomavirus.

    Science.gov (United States)

    Dey, Sumanta; De, Antara; Nandy, Ashesh

    2016-01-01

    Human papillomavirus (HPV) occurs in many types, some of which cause cervical, genital, and other cancers. While vaccination is available against the major cancer-causing HPV types, many others are not covered by these preventive measures. Herein, we present a bioinformatics study for the designing of multivalent peptide vaccines against multiple HPV types as an alternative strategy to the virus-like particle vaccines being used now. Our technique of rational design of peptide vaccines is expected to ensure stability of the vaccine against many cycles of mutational changes, elicit immune response, and negate autoimmune possibilities. Using the L1 capsid protein sequences, we identified several peptides for potential vaccine design for HPV 16, 18, 33, 35, 45, and 11 types. Although there are concerns about the epitope-binding affinities for the peptides identified in this process, the technique indicates possibilities of multivalent, adjuvanted, peptide vaccines against a wider range of HPV types, and tailor-made different combinations of the peptides to address frequency variations of types over different population groups as required for prophylaxis and at lower cost than are in use at the present time.

  13. Approach for Identifying Human Leukocyte Antigen (HLA)-DR Bound Peptides from Scarce Clinical Samples.

    Science.gov (United States)

    Heyder, Tina; Kohler, Maxie; Tarasova, Nataliya K; Haag, Sabrina; Rutishauser, Dorothea; Rivera, Natalia V; Sandin, Charlotta; Mia, Sohel; Malmström, Vivianne; Wheelock, Åsa M; Wahlström, Jan; Holmdahl, Rikard; Eklund, Anders; Zubarev, Roman A; Grunewald, Johan; Ytterberg, A Jimmy

    2016-09-01

    Immune-mediated diseases strongly associating with human leukocyte antigen (HLA) alleles are likely linked to specific antigens. These antigens are presented to T cells in the form of peptides bound to HLA molecules on antigen presenting cells, e.g. dendritic cells, macrophages or B cells. The identification of HLA-DR-bound peptides presents a valuable tool to investigate the human immunopeptidome. The lung is likely a key player in the activation of potentially auto-aggressive T cells prior to entering target tissues and inducing autoimmune disease. This makes the lung of exceptional interest and presents an ideal paradigm to study the human immunopeptidome and to identify antigenic peptides.Our previous investigation of HLA-DR peptide presentation in the lung required high numbers of cells (800 × 10(6) bronchoalveolar lavage (BAL) cells). Because BAL from healthy nonsmokers typically contains 10-15 × 10(6) cells, there is a need for a highly sensitive approach to study immunopeptides in the lungs of individual patients and controls.In this work, we analyzed the HLA-DR immunopeptidome in the lung by an optimized methodology to identify HLA-DR-bound peptides from low cell numbers. We used an Epstein-Barr Virus (EBV) immortalized B cell line and bronchoalveolar lavage (BAL) cells obtained from patients with sarcoidosis, an inflammatory T cell driven disease mainly occurring in the lung. Specifically, membrane complexes were isolated prior to immunoprecipitation, eluted peptides were identified by nanoLC-MS/MS and processed using the in-house developed ClusterMHCII software. With the optimized procedure we were able to identify peptides from 10 × 10(6) cells, which on average correspond to 10.9 peptides/million cells in EBV-B cells and 9.4 peptides/million cells in BAL cells. This work presents an optimized approach designed to identify HLA-DR-bound peptides from low numbers of cells, enabling the investigation of the BAL immunopeptidome from individual patients

  14. A Francisella tularensis live vaccine strain that improves stimulation of antigen-presenting cells does not enhance vaccine efficacy.

    Directory of Open Access Journals (Sweden)

    Deanna M Schmitt

    Full Text Available Vaccination is a proven strategy to mitigate morbidity and mortality of infectious diseases. The methodology of identifying and testing new vaccine candidates could be improved with rational design and in vitro testing prior to animal experimentation. The tularemia vaccine, Francisella tularensis live vaccine strain (LVS, does not elicit complete protection against lethal challenge with a virulent type A Francisella strain. One factor that may contribute to this poor performance is limited stimulation of antigen-presenting cells. In this study, we examined whether the interaction of genetically modified LVS strains with human antigen-presenting cells correlated with effectiveness as tularemia vaccine candidates. Human dendritic cells infected with wild-type LVS secrete low levels of proinflammatory cytokines, fail to upregulate costimulatory molecules, and activate human T cells poorly in vitro. One LVS mutant, strain 13B47, stimulated higher levels of proinflammatory cytokines from dendritic cells and macrophages and increased costimulatory molecule expression on dendritic cells compared to wild type. Additionally, 13B47-infected dendritic cells activated T cells more efficiently than LVS-infected cells. A deletion allele of the same gene in LVS displayed similar in vitro characteristics, but vaccination with this strain did not improve survival after challenge with a virulent Francisella strain. In vivo, this mutant was attenuated for growth and did not stimulate T cell responses in the lung comparable to wild type. Therefore, stimulation of antigen-presenting cells in vitro was improved by genetic modification of LVS, but did not correlate with efficacy against challenge in vivo within this model system.

  15. Epitope-based recombinant diagnostic antigen to distinguish natural infection from vaccination with hepatitis A virus vaccines.

    Science.gov (United States)

    Su, Qiudong; Guo, Minzhuo; Jia, Zhiyuan; Qiu, Feng; Lu, Xuexin; Gao, Yan; Meng, Qingling; Tian, Ruiguang; Bi, Shengli; Yi, Yao

    2016-07-01

    Hepatitis A virus (HAV) infection can stimulate the production of antibodies to structural and non-structural proteins of the virus. However, vaccination with an inactivated or attenuated HAV vaccine produces antibodies mainly against structural proteins, whereas no or very limited antibodies are produced against the non-structural proteins. Current diagnostic assays to determine exposure to HAV, such as the Abbott HAV AB test, detect antibodies only to the structural proteins and so are not able to distinguish a natural infection from vaccination with an inactivated or attenuated virus. Here, we constructed a recombinant tandem multi-epitope diagnostic antigen (designated 'H1') based on the immune-dominant epitopes of the non-structural proteins of HAV to distinguish the two situations. H1 protein expressed in Escherichia coli and purified by affinity and anion exchange chromatography was applied in a double-antigen sandwich ELISA for the detection of anti-non-structural HAV proteins, which was confirmed to distinguish a natural infection from vaccination with an inactivated or attenuated HAV vaccine. PMID:26994964

  16. mTOR inhibition improves antitumor effects of vaccination with antigen-encoding RNA.

    Science.gov (United States)

    Diken, Mustafa; Kreiter, Sebastian; Vascotto, Fulvia; Selmi, Abderraouf; Attig, Sebastian; Diekmann, Jan; Huber, Christoph; Türeci, Özlem; Sahin, Ugur

    2013-12-01

    Vaccination with in vitro transcribed RNA encoding tumor antigens is an emerging approach in cancer immunotherapy. Attempting to further improve RNA vaccine efficacy, we have explored combining RNA with immunomodulators such as rapamycin. Rapamycin, the inhibitor of mTOR, was used originally for immunosuppression. Recent reports in mouse systems, however, suggest that mTOR inhibition may enhance the formation and differentiation of the memory CD8(+) T-cell pool. Because memory T-cell formation is critical to the outcome of vaccination approaches, we studied the impact of rapamycin on the in vivo primed RNA vaccine-induced immune response using the chicken ovalbumin-expressing B16 melanoma model in C57BL/6 mice. Our data show that treatment with rapamycin at the effector-to-memory transition phase skews the vaccine-induced immune response toward the formation of a quantitatively and qualitatively superior memory pool and results in a better recall response. Tumor-infiltrating immune cells from these mice display a favorable ratio of effector versus suppressor cell populations. Survival of mice treated with the combined regimen of RNA vaccination with rapamycin is significantly longer (91.5 days) than that in the control groups receiving only one of these compounds (32 and 46 days, respectively). Our findings indicate that rapamycin enhances therapeutic efficacy of antigen-specific CD8(+) T cells induced by RNA vaccination, and we propose further clinical exploration of rapamycin as a component of immunotherapeutic regimens. PMID:24778131

  17. Structural analysis of the synthetic Duffy Binding Protein (DBP antigen DEKnull relevant for Plasmodium vivax malaria vaccine design.

    Directory of Open Access Journals (Sweden)

    Edwin Chen

    2015-03-01

    Full Text Available The Plasmodium vivax vaccine candidate Duffy Binding Protein (DBP is a protein necessary for P. vivax invasion of reticulocytes. The polymorphic nature of DBP induces strain-specific immune responses that pose unique challenges for vaccine development. DEKnull is a synthetic DBP based antigen that has been engineered through mutation to enhance induction of blocking inhibitory antibodies. We determined the x-ray crystal structure of DEKnull to identify if any conformational changes had occurred upon mutation. Computational and experimental analyses assessed immunogenicity differences between DBP and DEKnull epitopes. Functional binding assays with monoclonal antibodies were used to interrogate the available epitopes in DEKnull. We demonstrate that DEKnull is structurally similar to the parental Sal1 DBP. The DEKnull mutations do not cause peptide backbone shifts within the polymorphic loop, or at either the DBP dimerization interface or DARC receptor binding pockets, two important structurally conserved protective epitope motifs. All B-cell epitopes, except for the mutated DEK motif, are conserved between DEKnull and DBP. The DEKnull protein retains binding to conformationally dependent inhibitory antibodies. DEKnull is an iterative improvement of DBP as a vaccine candidate. DEKnull has reduced immunogenicity to polymorphic regions responsible for strain-specific immunity while retaining conserved protein folds necessary for induction of strain-transcending blocking inhibitory antibodies.

  18. Selective induction of cell-mediated immunity and protection of rhesus macaques from chronic SHIVKU2 infection by prophylactic vaccination with a conserved HIV-1 envelope peptide-cocktail

    International Nuclear Information System (INIS)

    Infection of Indian-origin rhesus macaques by the simian human immunodeficiency virus (SHIV) is considered to be a suitable preclinical model for directly testing efficacy of vaccine candidates based on the HIV-1 envelope. We used this model for prophylactic vaccination with a peptide-cocktail comprised of highly conserved HIV-1 envelope sequences immunogenic/antigenic in macaques and humans. Separate groups of macaques were immunized with the peptide-cocktail by intravenous and subcutaneous routes using autologous dendritic cells (DC) and Freund's adjuvant, respectively. The vaccine elicited antigen specific IFN-γ-producing cells and T-cell proliferation, but not HIV-neutralizing antibodies. The vaccinated animals also exhibited efficient cross-clade cytolytic activity against target cells expressing envelope proteins corresponding to HIV-1 strains representative of multiple clades that increased after intravenous challenge with pathogenic SHIVKU2. Virus-neutralizing antibodies were either undetectable or present only transiently at low levels in the control as well as vaccinated monkeys after infection. Significant control of plasma viremia leading to undetectable levels was achieved in majority of vaccinated monkeys compared to mock-vaccinated controls. Monkeys vaccinated with the peptide-cocktail using autologous DC, compared to Freund's adjuvant, and the mock-vaccinated animals, showed significantly higher IFN-γ production, higher levels of vaccine-specific IFN-γ producing CD4+ cells and significant control of plasma viremia. These results support DC-based vaccine delivery and the utility of the conserved HIV-1 envelope peptide-cocktail, capable of priming strong cell-mediated immunity, for potential inclusion in HIV vaccination strategies

  19. Combination of Two Candidate Subunit Vaccine Antigens Elicits Protective Immunity to Ricin and Anthrax Toxin in Mice

    OpenAIRE

    David J Vance; Rong, Yinghui; Brey, Robert N.; Mantis, Nicholas J.

    2014-01-01

    In an effort to develop combination vaccines for biodefense, we evaluated a ricin subunit antigen, RiVax, given in conjunction with an anthrax protective antigen, DNI. The combination led to high endpoint titer antibody response, neutralizing antibodies, and protective immunity against ricin and anthrax lethal toxin. This is a natural combination vaccine, since both antigens are recombinant subunit proteins that would be given to the same target population.

  20. Combination of two candidate subunit vaccine antigens elicits protective immunity to ricin and anthrax toxin in mice.

    Science.gov (United States)

    Vance, David J; Rong, Yinghui; Brey, Robert N; Mantis, Nicholas J

    2015-01-01

    In an effort to develop combination vaccines for biodefense, we evaluated a ricin subunit antigen, RiVax, given in conjunction with an anthrax protective antigen, DNI. The combination led to high endpoint titer antibody response, neutralizing antibodies, and protective immunity against ricin and anthrax lethal toxin. This is a natural combination vaccine, since both antigens are recombinant subunit proteins that would be given to the same target population. PMID:25475957

  1. HA03 as an Iranian Candidate Concealed Antigen for Vaccination against Hyalomma anatolicum anatolicum: Comparative Structural and In silico Studies

    OpenAIRE

    Mohammadi, A.; Aghaiypour, K; Keywanfar, H.; Paykari, H.,; Tajbakhsh, H.; Jalali, A.H.,; Safavieh, S.; Foroghi, A.

    2013-01-01

    In the last decades researchers had focused on developing a vaccine against tick based on protective antigen. Recombinant vaccines based on concealed antigen from Boophilus microplus have been developed in Australia and Cuba by the name of TICKGARD and GAVAC (De La Fuente and Kocan, 2006). Further studies on this antigen have shown some extent of protection against other species (De Vos et al., 2001). In Iran most important species is Hyalomma anatolicum and limited information about its cont...

  2. Immunogenicity in mice and rabbits of DNA vaccines expressing woodchuck hepatitis virus antigens.

    Science.gov (United States)

    Luxembourg, Alain; Hannaman, Drew; Wills, Ken; Bernard, Robert; Tennant, Bud C; Menne, Stephan; Cote, Paul J

    2008-07-29

    The licensed vaccine against hepatitis B virus (HBV) is an effective means to prevent infection, but is not an effective therapeutic strategy to treat established chronic infections when used alone. In an animal model of chronic HBV infection (the woodchuck experimentally infected with woodchuck hepatitis virus (WHV)), the combination of conventional vaccine and potent antiviral drugs has shown promise as a potential therapeutic intervention. This approach might be improved further through the application of newer vaccine technologies. In the present study, we evaluated electroporation (EP)-based intramuscular (i.m.) delivery of a codon-optimized DNA vaccine for the WHV surface antigen (WHsAg) in mice and rabbits. In mice, this immunization procedure compared favorably to vaccination by i.m. injection of the DNA vaccine or i.m. administration of a recombinant WHsAg-alum vaccine, exhibiting characteristics expected to be beneficial for a therapeutic vaccine strategy. These included dose efficiency, consistency, vigorous induction of antibody responses to WHsAg, as well as a Th1 bias. Following scale-up to rabbits, a species that approximates the size of the woodchuck, the EP dosing regimen was markedly more effective than conventional i.m. injection of the DNA vaccine. Taken together, these results provide the foundation for studies of EP-based DNA immunization in the woodchuck in order to further assess its potential as an immunotherapeutic approach for treatment of chronic HBV infection in humans. PMID:18556096

  3. Comparison of vaccine efficacy for different antigen delivery systems for infectious pancreatic necrosis virus vaccines in Atlantic salmon (Salmo salar L.) in a cohabitation challenge model.

    Science.gov (United States)

    Munang'andu, Hetron M; Fredriksen, Børge N; Mutoloki, Stephen; Brudeseth, Bjørn; Kuo, Tsun-Yung; Marjara, Inderjit S; Dalmo, Roy A; Evensen, Øystein

    2012-06-01

    Two strains of IPNV made by reverse genetics on the Norwegian Sp strain NVI-015 (GenBank AY379740) backbone encoding the virulent (T(217)A(221)) and avirulent (P(217)T(221)) motifs were used to prepare inactivated whole virus (IWV), nanoparticle vaccines with whole virus, Escherichia coli subunit encoding truncated VP2-TA and VP2-PT, VP2-TA and VP2-PT fusion antigens with putative translocating domains of Pseudomonas aeruginosa exotoxin, and plasmid DNA encoding segment A of the TA strain. Post challenge survival percentages (PCSP) showed that IWV vaccines conferred highest protection (PCSP=42-53) while nanoparticle, sub-unit recombinant and DNA vaccines fell short of the IWV vaccines in Atlantic salmon (Salmo salar L.) postsmolts challenged with the highly virulent Sp strain NVI-015 (TA strain) of IPNV after 560 degree days post vaccination. Antibody levels induced by these vaccines did not show antigenic differences between the virulent and avirulent motifs for vaccines made with the same antigen dose and delivery system after 8 weeks post vaccination. Our findings show that fish vaccinated with less potent vaccines comprising of nanoparticle, DNA and recombinant vaccines got infected much earlier and yielded to higher infection rates than fish vaccinated with IWV vaccines that were highly potent. Ability of the virulent (T(217)A(221)) and avirulent (P(217)T(221)) motifs to limit establishment of infection showed equal protection for vaccines made of the same antigen dose and delivery systems. Prevention of tissue damage linked to viral infection was eminent in the more potent vaccines than the less protective ones. Hence, there still remains the challenge of developing highly efficacious vaccines with the ability to eliminate the post challenge carrier state in IPNV vaccinology.

  4. Impaired Antigen-Specific Immune Response to Vaccines in Children with Antibody Production Defects.

    Science.gov (United States)

    Szczawinska-Poplonyk, Aleksandra; Breborowicz, Anna; Samara, Husam; Ossowska, Lidia; Dworacki, Grzegorz

    2015-08-01

    The impaired synthesis of antigen-specific antibodies, which is indispensable for an adaptive immune response to infections, is a fundamental pathomechanism that leads to clinical manifestations in children with antibody production defects. The aim of this study was to evaluate the synthesis of antigen-specific antibodies following immunization in relation to peripheral blood B cell subsets in young children with hypogammaglobulinemia. Twenty-two children, aged from 8 to 61 months, with a deficiency in one or more major immunoglobulin classes participated in the study. Postvaccination antibodies against tetanus and diphtheria toxoids, the surface antigen of the hepatitis B virus, and the capsular Haemophilus influenzae type b polysaccharide antigen were assessed along with an immunophenotypic evaluation of peripheral blood B lymph cell maturation. A deficiency of antibodies against the tetanus toxoid was assessed in 73% of cases and that against the diphtheria toxoid was assessed in 68% of cases, whereas a deficiency of antibodies against the surface antigen of the hepatitis B virus was revealed in 59% of the children included in the study. A defective response to immunization with a conjugate vaccine with the Haemophilus influenzae type b polysaccharide antigen was demonstrated in 55% of hypogammaglobulinemic patients. Increased proportions of transitional B lymph cells and an accumulation of plasmablasts accompanied antibody deficiencies. The defective response to vaccine protein and polysaccharide antigens is a predominating disorder of humoral immunity in children with hypogammaglobulinemia and may result from a dysfunctional state of the cellular elements of the immune system. PMID:26018535

  5. [Bioinformatics-based Design of Peptide Vaccine Candidates Targeting Spike Protein of MERS-CoV and Immunity analysis in Mice].

    Science.gov (United States)

    Lan, Jiaming; Lu, Shuai; Deng, Yao; Wen, Bo; Chen, Hong; Wang, Wen; Tan, Wenjie

    2016-01-01

    Middle East respiratory syndrome coronavirus (MERS-CoV) was identified as a novel human coronavirus and posed great threat to public health world wide,which calls for the development of effective and safe vaccine urgently. In the study, peptide epitopes tagrgeting spike antigen were predicted based on bioinformatics methods. Nine polypeptides with high scores were synthesized and linked to keyhole limpet hemocyanin (KLH). Female BALB/C mice were immunized with individual polypeptide-KLH, and the total IgG was detected by ELISA as well as the cellular mediated immunity (CMI) was analyzed using ELIs-pot assay. The results showed that an individual peptide of YVDVGPDSVKSACIEVDIQQTFFDKTWPRPIDVSKADGI could induce the highest level of total IgG as well as CMI (high frequency of IFN-γ secretion) against MERS-CoV antigen in mice. Our study identified a promising peptide vaccine candidate against MERS-CoV and provided an experimental support for bioinformatics-based design of peptide vaccine.

  6. Proteomics-driven Antigen Discovery for Development of Vaccines Against Gonorrhea.

    Science.gov (United States)

    Zielke, Ryszard A; Wierzbicki, Igor H; Baarda, Benjamin I; Gafken, Philip R; Soge, Olusegun O; Holmes, King K; Jerse, Ann E; Unemo, Magnus; Sikora, Aleksandra E

    2016-07-01

    Expanding efforts to develop preventive gonorrhea vaccines is critical because of the dire possibility of untreatable gonococcal infections. Reverse vaccinology, which includes genome and proteome mining, has proven very successful in the discovery of vaccine candidates against many pathogenic bacteria. However, progress with this approach for a gonorrhea vaccine remains in its infancy. Accordingly, we applied a comprehensive proteomic platform-isobaric tagging for absolute quantification coupled with two-dimensional liquid chromatography and mass spectrometry-to identify potential gonococcal vaccine antigens. Our previous analyses focused on cell envelopes and naturally released membrane vesicles derived from four different Neisseria gonorrhoeae strains. Here, we extended these studies to identify cell envelope proteins of N. gonorrhoeae that are ubiquitously expressed and specifically induced by physiologically relevant environmental stimuli: oxygen availability, iron deprivation, and the presence of human serum. Together, these studies enabled the identification of numerous potential gonorrhea vaccine targets. Initial characterization of five novel vaccine candidate antigens that were ubiquitously expressed under these different growth conditions demonstrated that homologs of BamA (NGO1801), LptD (NGO1715), and TamA (NGO1956), and two uncharacterized proteins, NGO2054 and NGO2139, were surface exposed, secreted via naturally released membrane vesicles, and elicited bactericidal antibodies that cross-reacted with a panel of temporally and geographically diverse isolates. In addition, analysis of polymorphisms at the nucleotide and amino acid levels showed that these vaccine candidates are highly conserved among N. gonorrhoeae strains. Finally, depletion of BamA caused a loss of N. gonorrhoeae viability, suggesting it may be an essential target. Together, our data strongly support the use of proteomics-driven discovery of potential vaccine targets as a sound

  7. Human Leukocyte Antigens Influence the Antibody Response to Hepatitis B Vaccine.

    Science.gov (United States)

    Jafarzadeh, Abdollah; Bagheri-Jamebozorgi, Masoome; Nemati, Maryam; Golsaz-Shirazi, Forough; Shokri, Fazel

    2015-06-01

    Hepatitis B virus (HBV) infection and its sequelae such as cirrhosis and hepatocellular carcinoma has remained a serious public health problem throughout the world. The WHO strategy for effective control of HBV infection and its complications is mass vaccination of neonates and children within the framework of Expanded Programme on Immunization (EPI). Vaccination with hepatitis B surface antigen (HBsAg) induces protective antibody response (anti-HBs ≥ 10 IU/L) in 90-99% of vaccinees. The lack of response to HBsAg has been attributed to a variety of immunological mechanisms, including defect in antigen presentation, defect in HBsAg-specific T and/or B cell repertoires, T-cell suppression, increase in the regulatory T cell count, lack of necessary help of T-cells for production of anti-HBs by B cells, defect in Th1 and/or Th2 cytokine production and selective killing of HBsAg-specific B-cells by human leukocyte antigen (HLA)-restricted cytotoxic T lymphocytes. The HLA complex plays an important role in many of these immunological processes. A variety of HLA class I, II, and III alleles and antigens have been reported to be associated with antibody response to HBsAg vaccination in different ethnic populations. Moreover, some HLA haplotypes were also associated with responsiveness to HBsAg. In this review the association of the HLA specificities with antibody response to hepatitis B (HB) vaccine is discussed. PMID:26546891

  8. Diversification of the antigen-specific T cell receptor repertoire after varicella zoster vaccination.

    Science.gov (United States)

    Qi, Qian; Cavanagh, Mary M; Le Saux, Sabine; NamKoong, Hong; Kim, Chulwoo; Turgano, Emerson; Liu, Yi; Wang, Chen; Mackey, Sally; Swan, Gary E; Dekker, Cornelia L; Olshen, Richard A; Boyd, Scott D; Weyand, Cornelia M; Tian, Lu; Goronzy, Jörg J

    2016-03-30

    Diversity and size of the antigen-specific T cell receptor (TCR) repertoire are two critical determinants for successful control of chronic infection. Varicella zoster virus (VZV) that establishes latency during childhood can escape control mechanisms, in particular with increasing age. We examined the TCR diversity of VZV-reactive CD4 T cells in individuals older than 50 years by studying three identical twin pairs and three unrelated individuals before and after vaccination with live attenuated VZV. Although all individuals had a small number of dominant T cell clones, the breadth of the VZV-specific repertoire differed markedly. A genetic influence was seen for the sharing of individual TCR sequences from antigen-reactive cells but not for repertoire richness or the selection of dominant clones. VZV vaccination favored the expansion of infrequent VZV antigen-reactive TCRs, including those from naïve T cells with lesser boosting of dominant T cell clones. Thus, vaccination does not reinforce the in vivo selection that occurred during chronic infection but leads to a diversification of the VZV-reactive T cell repertoire. However, a single-booster immunization seems insufficient to establish new clonal dominance. Our results suggest that repertoire analysis of antigen-specific TCRs can be an important readout to assess whether a vaccination was able to generate memory cells in clonal sizes that are necessary for immune protection.

  9. Diversification of the antigen-specific T cell receptor repertoire after varicella zoster vaccination.

    Science.gov (United States)

    Qi, Qian; Cavanagh, Mary M; Le Saux, Sabine; NamKoong, Hong; Kim, Chulwoo; Turgano, Emerson; Liu, Yi; Wang, Chen; Mackey, Sally; Swan, Gary E; Dekker, Cornelia L; Olshen, Richard A; Boyd, Scott D; Weyand, Cornelia M; Tian, Lu; Goronzy, Jörg J

    2016-03-30

    Diversity and size of the antigen-specific T cell receptor (TCR) repertoire are two critical determinants for successful control of chronic infection. Varicella zoster virus (VZV) that establishes latency during childhood can escape control mechanisms, in particular with increasing age. We examined the TCR diversity of VZV-reactive CD4 T cells in individuals older than 50 years by studying three identical twin pairs and three unrelated individuals before and after vaccination with live attenuated VZV. Although all individuals had a small number of dominant T cell clones, the breadth of the VZV-specific repertoire differed markedly. A genetic influence was seen for the sharing of individual TCR sequences from antigen-reactive cells but not for repertoire richness or the selection of dominant clones. VZV vaccination favored the expansion of infrequent VZV antigen-reactive TCRs, including those from naïve T cells with lesser boosting of dominant T cell clones. Thus, vaccination does not reinforce the in vivo selection that occurred during chronic infection but leads to a diversification of the VZV-reactive T cell repertoire. However, a single-booster immunization seems insufficient to establish new clonal dominance. Our results suggest that repertoire analysis of antigen-specific TCRs can be an important readout to assess whether a vaccination was able to generate memory cells in clonal sizes that are necessary for immune protection. PMID:27030598

  10. Performance of two Bm86 antigen vaccin formulation against tick using crossbreed bovines in stall test.

    Science.gov (United States)

    Andreotti, Renato

    2006-01-01

    Cattle tick control remains a serious problem for cattle farms in Brazil due to the limited success achieved with chemicals. In Brazil, the use of vaccines for tick control associated with the use of chemicals and pasture rotation may open possibilities for integrated control. However, it is important to know whether regional Boophilus microplus strains are sensitive to antibodies produced by the available antigens: antigen preparations Gavac™ and TickGard(PLUS). The aim of this research was to evaluate the performance of two Bm86 antigen vaccine formulation against tick using crossbred bovines in stall test antigen against a regional B. microplus strain. The experiment was carried out in central Brazil (20 degrees 27'S, 54 degrees 37'W). A trial was conducted in stall conditions on crossbred cattle under controlled infestation. Two groups of 16 animals each, homogeneous in weight and sex, were vaccinated with Gavac™ or TickGard(PLUS), two groups of eight animals as control. Challenge was performed on three alternate days, with 5,000 larvae each time, beginning 21 days after the second injection. The antibody response was measured by ELISA and vaccinated animals presented immune response considering IgG levels. The results showed 49.2% and 46.4% protection efficacy for Gavac™ and TickGard(PLUS), respectively. PMID:16978472

  11. Identification of a Novel P190-Derived Breakpoint Peptide Suitable for Peptide Vaccine Therapeutic Approach in Ph+ Acute Lymphoblastic Leukemia Patients

    Directory of Open Access Journals (Sweden)

    Micaela Ippoliti

    2012-01-01

    Full Text Available Ph+ acute lymphoblastic leukemia (Ph+ ALL is a high-risk acute leukemia with poor prognosis, in which the specific t(9;22(q34;q11 translocation results in a chimeric bcr-abl (e1a2 breakpoint and in a 190 KD protein (p190 with constitutive tyrosine kinase activity. The advent of first- and second-generation tyrosine kinase inhibitors (TKIs improved the short-term outcome of Ph+ ALL patients not eligible for allo-SCT; yet disease recurrence is almost inevitable. Peptides derived from p190-breakpoint area are leukemia-specific antigens that may mediate an antitumor response toward p190+ leukemia cells. We identified one peptide named p190-13 able to induce in vitro peptide-specific CD4+ T cell proliferation in Ph+ ALL patients in complete remission during TKIs. Thus this peptide appears a good candidate for developing an immune target vaccine strategy possibly synergizing with TKIs for remission maintenance.

  12. Triple peptide vaccination as consolidation treatment in women affected by ovarian and breast cancer: Clinical and immunological data of a phase I/II clinical trial

    Science.gov (United States)

    ANTONILLI, MORENA; RAHIMI, HASSAN; VISCONTI, VALERIA; NAPOLETANO, CHIARA; RUSCITO, ILARY; ZIZZARI, ILARIA GRAZIA; CAPONNETTO, SALVATORE; BARCHIESI, GIACOMO; IADAROLA, ROBERTA; PIERELLI, LUCA; RUGHETTI, AURELIA; BELLATI, FILIPPO; PANICI, PIERLUIGI BENEDETTI; NUTI, MARIANNA

    2016-01-01

    Vaccination with priming and expansion of tumour reacting T cells is an important therapeutic option to be used in combination with novel checkpoint inhibitors to increase the specificity of the T cell infiltrate and the efficacy of the treatment. In this phase I/II study, 14 high-risk disease-free ovarian (OC) and breast cancer (BC) patients after completion of standard therapies were vaccinated with MUC1, ErbB2 and carcinoembryonic antigen (CEA) HLA-A2+-restricted peptides and Montanide. Patients were subjected to 6 doses of vaccine every two weeks and a recall dose after 3 months. ECOG grade 2 toxicity was observed at the injection site. Eight out of 14 patients showed specific CD8+ T cells to at least one antigen. None of 4 patients vaccinated for compassionate use showed a CD8 activation. An OC patient who suffered from a lymph nodal recurrence, showed specific anti-ErbB2 CD8+ T cells in the bulky aortic lymph nodes suggesting homing of the activated T cells. Results confirm that peptide vaccination strategy is feasible, safe and well tolerated. In particular OC patients appear to show a higher response rate compared to BC patients. Vaccination generates a long-lasting immune response, which is strongly enhanced by recall administrations. The clinical outcome of patients enrolled in the trial appears favourable, having registered no deceased patients with a minimum follow-up of 8 years. These promising data, in line with the results of similar studies, the high compliance of patients observed and the favourable toxicity profile, support future trials of peptide vaccination in clinically disease-free patients who have completed standard treatments. PMID:26892612

  13. Plasmodium falciparum serine repeat antigen 5 (SE36) as a malaria vaccine candidate.

    Science.gov (United States)

    Palacpac, Nirianne Marie Q; Arisue, Nobuko; Tougan, Takahiro; Ishii, Ken J; Horii, Toshihiro

    2011-08-11

    A devastating disease spread by mosquitoes with high-efficiency, malaria imposes an enormous burden for which no licensed vaccine currently exists. Although the genome complexity of the parasite has made vaccine development tenuous, an effective malaria vaccine would be a valuable tool for control, elimination and eventual eradication. The Plasmodium serine repeat antigen 5 (SERA5) is an abundant asexual blood stage antigen that does not show any antigenic variation and exhibits limited polymorphism, making it a suitable vaccine candidate. Identified by comparing the IgG status of people in endemic areas with protective immunity and those with malaria symptoms, the vaccine potential of the N-terminal domain of Plasmodium falciparum SERA5 is also strongly supported by experimental data and immune responses both measured in vitro and in animal challenge models. The current understanding of SERA5 will be presented, particularly in relation to its path towards clinical development. The review highlights lessons learned and sorts out issues upon which further research efforts are needed. PMID:21718740

  14. T cell responses to hepatitis B surface antigen are detectable in non-vaccinated individuals

    Institute of Scientific and Technical Information of China (English)

    Martin R Weihrauch; Michael von Bergwelt-Baildon; Milos Kandic; Martin Weskott; Winfried Klamp; Joachim R(o)sier; Joachim L Schultze

    2008-01-01

    AIM: To evaluate, whether humoral hepatitis-B-vaccine non-responders also fail to mount a T cell response and to compare these results to normal vaccinees.METHODS: Fourty-seven health care employees were enrolled in this study including all available nonresponders (n = 13) with an anti-HBsAg titer 1000 kU/L as controls.PBMC from all subjects were analyzed by IFN-γ and IL-4 ELISPOT assays for the presence of hepatitis B surface antigen (HBsAg) reactive T cells.RESULTS: Non-responders and low-responders had no or only very limited T cell responses, respectively.Individuals responding to vaccination with the induction of a high anti-HBsAg titer showed a strong T cell response after the third vaccination.Surprisingly, these individuals showed response even before the first vaccination.T cell response to control antigens and mitogens was similar in all groups.CONCLUSION: Our data suggest that there is no general immune deficiency in non-/low-responders.Thus,we hypothesize that the induction of anti-HBsAg responses by vaccination is significantly dependent on the pre-existing T cell repertoire against the specific antigen rather than the presence of a general T cell defect.

  15. Three Candidate Peptide-Vaccines in Combination To Induce High Levels of Multiantibodies Against HIV-1

    Institute of Scientific and Technical Information of China (English)

    王颖; 田海军; 秦莉; 朱梅; 陈应华

    2001-01-01

    N-and C-domains of human immunodeficiency virus type 1 (HIV-1) gp41 are demonstrated to play an important role in HIV-entry and prevention. In addition, the V3 loop on gp120 was identified as the principal neutralizing determinant (PND). Based on the fact that a combination of several monoclonal antibodies to different neutralizing epitopes showed great protection against intravenous challenge and vaginal transmission of pathogenic HIV-1/Simian immunodeficiency virus (SIV) chimeric virus on macaques, three candidate peptide-vaccines were prepared and used in combination to induce high levels of multiantibodies against HIV-1. The three peptides contained important functional regions on HIV-1 gp160. The N-domain peptide (P1: aa550-579) and C-domain peptide (P2: aa633-662) of gp41 and V3 peptide (P3: aa301-328) of gp120 were conjugated with bovine serum albumin (BSA) using the glutaraldehyde method. After the vaccination course, each of the three candidate peptide-vaccines induced strong antibody response in rabbits. The three vaccines used in combination induced high levels of multiantibodies against the peptides of the N-and C-domains and the V3 Ioop, with the titer of antibodies up to 1: 6400-1: 25 600 in rabbit sera in comparison with the titer of 1: 800-1:3200 induced by rgp41 or rgp160. Our results indicate that immunogenicities of the N-and C-domains and the V3 loop in these three candidate peptide-vaccines were clearly stronger than those induced by rgp41 or rgp160, and these peptide-vaccines used in combination synchronously induced high levels of multiantibodies against HIV-1, suggesting that used in combination they may provide a new vaccine-strategy to induce strong multi-antiviral activity.

  16. Structural Basis for Antigenic Peptide Recognition and Processing by Endoplasmic Reticulum (ER) Aminopeptidase 2.

    Science.gov (United States)

    Mpakali, Anastasia; Giastas, Petros; Mathioudakis, Nikolas; Mavridis, Irene M; Saridakis, Emmanuel; Stratikos, Efstratios

    2015-10-23

    Endoplasmic reticulum (ER) aminopeptidases process antigenic peptide precursors to generate epitopes for presentation by MHC class I molecules and help shape the antigenic peptide repertoire and cytotoxic T-cell responses. To perform this function, ER aminopeptidases have to recognize and process a vast variety of peptide sequences. To understand how these enzymes recognize substrates, we determined crystal structures of ER aminopeptidase 2 (ERAP2) in complex with a substrate analogue and a peptidic product to 2.5 and 2.7 Å, respectively, and compared them to the apo-form structure determined to 3.0 Å. The peptides were found within the internal cavity of the enzyme with no direct access to the outside solvent. The substrate analogue extends away from the catalytic center toward the distal end of the internal cavity, making interactions with several shallow pockets along the path. A similar configuration was evident for the peptidic product, although decreasing electron density toward its C terminus indicated progressive disorder. Enzymatic analysis confirmed that visualized interactions can either positively or negatively impact in vitro trimming rates. Opportunistic side-chain interactions and lack of deep specificity pockets support a limited-selectivity model for antigenic peptide processing by ERAP2. In contrast to proposed models for the homologous ERAP1, no specific recognition of the peptide C terminus by ERAP2 was evident, consistent with functional differences in length selection and self-activation between these two enzymes. Our results suggest that ERAP2 selects substrates by sequestering them in its internal cavity and allowing opportunistic interactions to determine trimming rates, thus combining substrate permissiveness with sequence bias. PMID:26381406

  17. The Peptide Vaccine Combined with Prior Immunization of a Conventional Diphtheria-Tetanus Toxoid Vaccine Induced Amyloid β Binding Antibodies on Cynomolgus Monkeys and Guinea Pigs

    Directory of Open Access Journals (Sweden)

    Akira Yano

    2015-01-01

    Full Text Available The reduction of brain amyloid beta (Aβ peptides by anti-Aβ antibodies is one of the possible therapies for Alzheimer’s disease. We previously reported that the Aβ peptide vaccine including the T-cell epitope of diphtheria-tetanus combined toxoid (DT induced anti-Aβ antibodies, and the prior immunization with conventional DT vaccine enhanced the immunogenicity of the peptide. Cynomolgus monkeys were given the peptide vaccine subcutaneously in combination with the prior DT vaccination. Vaccination with a similar regimen was also performed on guinea pigs. The peptide vaccine induced anti-Aβ antibodies in cynomolgus monkeys and guinea pigs without chemical adjuvants, and excessive immune responses were not observed. Those antibodies could preferentially recognize Aβ40, and Aβ42 compared to Aβ fibrils. The levels of serum anti-Aβ antibodies and plasma Aβ peptides increased in both animals and decreased the brain Aβ40 level of guinea pigs. The peptide vaccine could induce a similar binding profile of anti-Aβ antibodies in cynomolgus monkeys and guinea pigs. The peptide vaccination could be expected to reduce the brain Aβ peptides and their toxic effects via clearance of Aβ peptides by generated antibodies.

  18. Recombinant peptide replicates immunogenicity of synthetic linear peptide chimera for use as pre-erythrocytic stage malaria vaccine

    OpenAIRE

    Silva-Flannery, Luciana M.; Cabrera-Mora, Monica; Jiang, Jianlin; Moreno, Alberto

    2008-01-01

    Synthetic linear peptide chimeras (LPCscys+) show promise as delivery platforms for malaria subunit vaccines. Maximal immune response to LPCscys+ in rodent malaria models depends upon formation of cross-linkages to generate homopolymers, presenting challenges for vaccine production. To replicate the immunogenicity of LPCscys+ using a recombinant approach, we designed a recombinant LPC (rLPC) based on Plasmodium yoelii circumsporozoite protein-specific sequences of 208 amino acids consisting o...

  19. Active self-healing encapsulation of vaccine antigens in PLGA microspheres

    Science.gov (United States)

    Desai, Kashappa-Goud H.; Schwendeman, Steven P.

    2013-01-01

    Herein, we describe the detailed development of a simple and effective method to microencapsulate vaccine antigens in poly(lactic-co-glycolic acid) (PLGA) by simple mixing of preformed active self-microencapsulating (SM) PLGA microspheres in a low concentration aqueous antigen solution at modest temperature (10-38 °C). Co-encapsulating protein-sorbing vaccine adjuvants and polymer plasticizers were used to “actively” load the protein in the polymer pores and facilitate polymer self-healing at temperature > hydrated polymer glass transition temperature, respectively. The microsphere formulation parameters and loading conditions to provide optimal active self-healing microencapsulation of vaccine antigen in PLGA was investigated. Active self-healing encapsulation of two vaccine antigens, ovalbumin and tetanus toxoid (TT), in PLGA microspheres was adjusted by preparing blank microspheres containing different vaccine adjuvant (aluminum hydroxide (Al(OH)3) or calcium phosphate). Active loading of vaccine antigen in Al(OH)3-PLGA microspheres was found to: a) increase proportionally with an increasing loading of Al(OH)3 (0.88-3 wt%) and addition of porosigen, b) decrease when the inner Al(OH)3/trehalose phase to 1 mL outer oil phase and size of microspheres was respectively > 0.2 mL and 63 μm, and c) change negligibly by PLGA concentration and initial incubation (loading) temperature. Encapsulation of protein sorbing Al(OH)3 in PLGA microspheres resulted in suppression of self-healing of PLGA pores, which was then overcome by improving polymer chain mobility, which in turn was accomplished by coincorporating hydrophobic plasticizers in PLGA. Active self-healing microencapsulation of manufacturing process-labile TT in PLGA was found to: a) obviate micronization- and organic solvent-induced TT degradation, b) improve antigen loading (1.4-1.8 wt% TT) and encapsulation efficiency (~ 97%), c) provide nearly homogeneous distribution and stabilization of antigen in polymer

  20. A Nanoparticle Based Sp17 Peptide Vaccine Exposes New Immuno-Dominant and Species Cross-reactive B Cell Epitopes

    Directory of Open Access Journals (Sweden)

    Sue D. Xiang

    2015-10-01

    Full Text Available Sperm protein antigen 17 (Sp17, expressed in primary as well as in metastatic lesions in >83% of patients with ovarian cancer, is a promising ovarian cancer vaccine candidate. Herein we describe the formulation of nanoparticle based vaccines based on human Sp17 (hSp17 sequence derived peptides, and map the immuno-dominant T cell and antibody epitopes induced using such formulations. The primary T and B cell immuno-dominant region within Sp17 was found to be the same when using biocompatible nanoparticle carriers or the conventional “mix-in” pro-inflammatory adjuvant CpG, both mapping to amino acids (aa 111–142. However, delivery of hSp17111–142 as a nanoparticle conjugate promoted a number of new properties, changing the dominant antibody isotype induced from IgG2a to IgG1 and the fine specificity of the B cell epitopes within hSp17111–142, from an immuno-dominant region 134–142 aa for CpG, to region 121–138 aa for nanoparticles. Associated with this change in specificity was a substantial increase in antibody cross-reactivity between mouse and human Sp17. These results indicate conjugation of antigen to nanoparticles can have major effects on fine antigen specificity, which surprisingly could be beneficially used to increase the cross-reactivity of antibody responses.

  1. A Nanoparticle Based Sp17 Peptide Vaccine Exposes New Immuno-Dominant and Species Cross-reactive B Cell Epitopes.

    Science.gov (United States)

    Xiang, Sue D; Gao, Qian; Wilson, Kirsty L; Heyerick, Arne; Plebanski, Magdalena

    2015-01-01

    Sperm protein antigen 17 (Sp17), expressed in primary as well as in metastatic lesions in >83% of patients with ovarian cancer, is a promising ovarian cancer vaccine candidate. Herein we describe the formulation of nanoparticle based vaccines based on human Sp17 (hSp17) sequence derived peptides, and map the immuno-dominant T cell and antibody epitopes induced using such formulations. The primary T and B cell immuno-dominant region within Sp17 was found to be the same when using biocompatible nanoparticle carriers or the conventional "mix-in" pro-inflammatory adjuvant CpG, both mapping to amino acids (aa) 111-142. However, delivery of hSp17111-142 as a nanoparticle conjugate promoted a number of new properties, changing the dominant antibody isotype induced from IgG2a to IgG1 and the fine specificity of the B cell epitopes within hSp17111-142, from an immuno-dominant region 134-142 aa for CpG, to region 121-138 aa for nanoparticles. Associated with this change in specificity was a substantial increase in antibody cross-reactivity between mouse and human Sp17. These results indicate conjugation of antigen to nanoparticles can have major effects on fine antigen specificity, which surprisingly could be beneficially used to increase the cross-reactivity of antibody responses. PMID:26529027

  2. Long term hepatitis B vaccine in infants born to hepatitis B e antigen positive mothers

    OpenAIRE

    Poovorawan, Y.; Sanpavat, S.; Chumdermpadetsuk, S.; Safary, A.

    1997-01-01

    Neonates of hepatitis B surface antigen (HBsAg) positive and hepatitis B encoded antigen (HBeAg) positive mothers received 10 µg of recombinant hepatitis B vaccine at months 0, 1, 6, or 0, 1, 2, 12, with or without immunoglobulin at birth, and were followed up to the age of 8 years for HBsAg, anti-HBc, and anti-HBs. Some were boosted at month 60. The overall vaccine protection at month 12 was 96.2%. No child became a chronic carrier beyond the age of 3 years, showing that this vaccine provide...

  3. Rapid and sustained CD4(+) T-cell-independent immunity from adenovirus-encoded vaccine antigens

    DEFF Research Database (Denmark)

    Holst, Peter J; Bartholdy, Christina; Buus, Anette Stryhn;

    2007-01-01

    Many novel vaccine strategies rely on recombinant viral vectors for antigen delivery, and adenovirus vectors have emerged among the most potent of these. In this report, we have compared the immune response induced through priming with adenovirus vector-encoded full-length viral protein...... to that elicited with an adenovirus-encoded minimal epitope covalently linked to beta(2)-microglobulin. We demonstrate that the beta(2)-microglobulin-linked epitope induced an accelerated and augmented CD8(+) T-cell response. Furthermore, the immunity conferred by vaccination with beta(2)-microglobulin...... in the absence of CD4(+) T-cell help were sustained in the long term and able to expand and control a secondary challenge with LCMV. Our results demonstrate that modifications to the antigen used in adenovirus vaccines may be used to improve the induced T-cell response. Such a strategy for CD4(+) T...

  4. Construction and characterization of an HCV-derived multi-epitope peptide antigen containing B-cell HVR1 mimotopes and T-cell conserved epitopes

    Institute of Scientific and Technical Information of China (English)

    GAO; Jun; GONG; Yuping; ZHAO; Ping; ZHU; Qing; YANG; Xiaoping; QI; Zhongtian

    2006-01-01

    Hepatitis C (HCV) genome is highly variable, particularly in the hypervariable region 1(HVR1) of its E2 envelope gene. The variability of HCV genome has been a major obstacle for developing HCV vaccines. Due to B-cell HVR1 mimotopes mimicking the antigenicity of natural HVR1 epitopes and some T-cell epitopes from the consensus sequence of HCV genes conserving among the different HCV genotypes, we synthesized an minigene of HCV-derived multi-epitope peptide antigen (CMEP), which contains 9 B-cell HVR1 mimotopes in E2, 2 conserved CTL epitopes in C, 1conserved CTL epitope in NS3 and 1 conserved Th epitope in NS3. This minigene was cloned into a GST expression vector to generate a fusion protein GST-CMER The immunogenic properties of CEMP were characterized by HCV infected patients' sera, and found that the reactivity frequency reached 75%. The cross reactivity of anti-CEMP antibody with different natural HVR1 variants was up to 90%. Meanwhile, we constructed an HCV DNA vaccine candidate, plasmid pVAX1.0-st-CMEP carrying the recombinant gene (st) of a secretion signal peptide and PADRE universal Th cell epitope sequence in front of the CMEP minigene. Immunization of rabbits with pVAX1.0-st-CMEP resulted in the production of antibody, which was of the same cross reactivity as the fusion protein GST-CMEP.Our findings indicate that the HCV-derived multi-epitope peptide antigen in some degree possessed the characteristics of neutralizing HCV epitopes, and would be of the value as a candidate for the development of HCV vaccines.

  5. Development of Yersinia pestis F1 antigen-loaded microspheres vaccine against plague

    Directory of Open Access Journals (Sweden)

    Huang SS

    2014-02-01

    Full Text Available Shih-shiung Huang,1 I-Hsun Li,2,3 Po-da Hong,1 Ming-kung Yeh1,2,41Biomedical Engineering Program, Graduate Institute of Engineering, Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan, Republic of China; 2School of Pharmacy, 3Department of Pharmacy Practice, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China; 4Food and Drug Administration, Ministry of Health and Welfare, Taipei, Taiwan, Republic of ChinaAbstract: Yersinia pestis F1 antigen-loaded poly(DL-lactide-co-glycolide/polyethylene glycol (PEG (PLGA/PEG microspheres were produced using a water-in-oil-in-water emulsion/solvent extraction technique and assayed for their percent yield, entrapment efficiency, surface morphology, particle size, zeta potential, in vitro release properties, and in vivo animal protect efficacy. The Y. pestis F1 antigen-loaded microspheres (mean particle size 3.8 µm exhibited a high loading capacity (4.5% w/w, yield (85.2%, and entrapment efficiency (38.1%, and presented a controlled in vitro release profile with a low initial burst (18.5%, then continued to release Y. pestis F1 antigen over 70 days. The distribution (% of Y. pestis F1 on the microspheres surface, outer layer, and core was 3.1%, 28.9%, and 60.7%, respectively. A steady release rate was noticed to be 0.55 µg Y. pestis F1 antigen/mg microspheres/day of Y. pestis F1 antigen release maintained for 42 days. The cumulative release amount at the 1st, 28th, and 42nd days was 8.2, 26.7, and 31.0 µg Y. pestis F1 antigen/mg microspheres, respectively. The 100 times median lethal dose 50% (LD50 of Y. pestis Yokohama-R strain by intraperitoneal injection challenge in mice test, in which mice received one dose of 40 µg F1 antigen content of PLGA/PEG microspheres, F1 antigen in Al(OH3, and in comparison with F1 antigen in Al(OH3 vaccine in two doses, was evaluated after given by subcutaneous

  6. GM-CSF production allows the identification of immunoprevalent antigens recognized by human CD4+ T cells following smallpox vaccination.

    Directory of Open Access Journals (Sweden)

    Valeria Judkowski

    Full Text Available The threat of bioterrorism with smallpox and the broad use of vaccinia vectors for other vaccines have led to the resurgence in the study of vaccinia immunological memory. The importance of the role of CD4+ T cells in the control of vaccinia infection is well known. However, more CD8+ than CD4+ T cell epitopes recognized by human subjects immunized with vaccinia virus have been reported. This could be, in part, due to the fact that most of the studies that have identified human CD4+ specific protein-derived fragments or peptides have used IFN-γ production to evaluate vaccinia specific T cell responses. Based on these findings, we reasoned that analyzing a large panel of cytokines would permit us to generate a more complete analysis of the CD4 T cell responses. The results presented provide clear evidence that TNF-α is an excellent readout of vaccinia specificity and that other cytokines such as GM-CSF can be used to evaluate the reactivity of CD4+ T cells in response to vaccinia antigens. Furthermore, using these cytokines as readout of vaccinia specificity, we present the identification of novel peptides from immunoprevalent vaccinia proteins recognized by CD4+ T cells derived from smallpox vaccinated human subjects. In conclusion, we describe a "T cell-driven" methodology that can be implemented to determine the specificity of the T cell response upon vaccination or infection. Together, the single pathogen in vitro stimulation, the selection of CD4+ T cells specific to the pathogen by limiting dilution, the evaluation of pathogen specificity by detecting multiple cytokines, and the screening of the clones with synthetic combinatorial libraries, constitutes a novel and valuable approach for the elucidation of human CD4+ T cell specificity in response to large pathogens.

  7. Cancer testis antigen vaccination affords long-term protection in a murine model of ovarian cancer.

    Directory of Open Access Journals (Sweden)

    Maurizio Chiriva-Internati

    Full Text Available Sperm protein (Sp17 is an attractive target for ovarian cancer (OC vaccines because of its over-expression in primary as well as in metastatic lesions, at all stages of the disease. Our studies suggest that a Sp17-based vaccine can induce an enduring defense against OC development in C57BL/6 mice with ID8 cells, following prophylactic and therapeutic treatments. This is the first time that a mouse counterpart of a cancer testis antigen (Sp17 was shown to be expressed in an OC mouse model, and that vaccination against this antigen significantly controlled tumor growth. Our study shows that the CpG-adjuvated Sp17 vaccine overcomes the issue of immunologic tolerance, the major barrier to the development of effective immunotherapy for OC. Furthermore, this study provides a better understanding of OC biology by showing that Th-17 cells activation and contemporary immunosuppressive T-reg cells inhibition is required for vaccine efficacy. Taken together, these results indicate that prophylactic and therapeutic vaccinations can induce long-standing protection against OC and delay tumor growth, suggesting that this strategy may provide additional treatments of human OC and the prevention of disease onset in women with a family history of OC.

  8. Plant-Based Vaccine: Mice Immunized with Chloroplast-Derived Anthrax Protective Antigen Survive Anthrax Lethal Toxin Challenge

    OpenAIRE

    Koya, Vijay; Moayeri, Mahtab; Leppla, Stephen H.; Daniell, Henry

    2005-01-01

    The currently available human vaccine for anthrax, derived from the culture supernatant of Bacillus anthracis, contains the protective antigen (PA) and traces of the lethal and edema factors, which may contribute to adverse side effects associated with this vaccine. Therefore, an effective expression system that can provide a clean, safe, and efficacious vaccine is required. In an effort to produce anthrax vaccine in large quantities and free of extraneous bacterial contaminants, PA was expre...

  9. Tumor-reactive CD8+ T-cell responses after vaccination with NY-ESO-1 peptide, CpG 7909 and Montanide ISA-51: association with survival.

    Science.gov (United States)

    Karbach, Julia; Gnjatic, Sacha; Bender, Armin; Neumann, Antje; Weidmann, Eckhart; Yuan, Jianda; Ferrara, Cathy A; Hoffmann, Eric; Old, Lloyd J; Altorki, Nasser K; Jäger, Elke

    2010-02-15

    Peptide-based vaccines have led to the induction of antigen-specific CD8(+) T-cell responses in patients with NY-ESO-1 positive cancers. However, vaccine-induced T-cell responses did not generally correlate with improved survival. Therefore, we tested whether a synthetic CpG 7909 ODN (deoxycytidyl-deoxyguanosin oligodeoxy-nucleotides) mixed with NY-ESO-1 peptide p157-165 and incomplete Freund's adjuvants (Montanide(R) ISA-51) led to enhanced NY-ESO-1 antigen-specific CD8(+) immune responses in patients with NY-ESO-1 or LAGE-1 expressing tumors. Of 14 HLA-A2+ patients enrolled in the study, 5 patients withdrew prematurely because of progressive disease and 9 patients completed 1 cycle of immunization. Nine of 14 patients developed measurable and sustained antigen-specific CD8(+) T-cell responses: Four had detectable CD8+ T-cells against NY-ESO-1 after only 2 vaccinations, whereas 5 patients showed a late-onset but durable induction of NY-ESO-1 p157-165 specific T-cell response during continued vaccination after 4 months. In 6 patients, vaccine-induced antigen-specific T-cells became detectable ex vivo and reached frequencies of up to 0.16 % of all circulating CD8(+) T-cells. Postvaccine T-cell clones were shown to recognize and lyse NY-ESO-1 expressing tumor cell lines in vitro. In 6 of 9 patients developing NY-ESO-1-specific immune responses, a favorable clinical outcome with overall survival times of 43+, 42+, 42+, 39+, 36+ and 27+ months, respectively, was observed.

  10. Characterization of the Antigen Processing Machinery and Endogenous Peptide Presentation of a Bat MHC Class I Molecule.

    Science.gov (United States)

    Wynne, James W; Woon, Amanda P; Dudek, Nadine L; Croft, Nathan P; Ng, Justin H J; Baker, Michelle L; Wang, Lin-Fa; Purcell, Anthony W

    2016-06-01

    Bats are a major reservoir of emerging and re-emerging infectious diseases, including severe acute respiratory syndrome-like coronaviruses, henipaviruses, and Ebola virus. Although highly pathogenic to their spillover hosts, bats harbor these viruses, and a large number of other viruses, with little or no clinical signs of disease. How bats asymptomatically coexist with these viruses is unknown. In particular, little is known about bat adaptive immunity, and the presence of functional MHC molecules is mostly inferred from recently described genomes. In this study, we used an affinity purification/mass spectrometry approach to demonstrate that a bat MHC class I molecule, Ptal-N*01:01, binds antigenic peptides and associates with peptide-loading complex components. We identified several bat MHC class I-binding partners, including calnexin, calreticulin, protein disulfide isomerase A3, tapasin, TAP1, and TAP2. Additionally, endogenous peptide ligands isolated from Ptal-N*01:01 displayed a relatively broad length distribution and an unusual preference for a C-terminal proline residue. Finally, we demonstrate that this preference for C-terminal proline residues was observed in Hendra virus-derived peptides presented by Ptal-N*01:01 on the surface of infected cells. To our knowledge, this is the first study to identify endogenous and viral MHC class I ligands for any bat species and, as such, provides an important avenue for monitoring and development of vaccines against major bat-borne viruses both in the reservoir and spillover hosts. Additionally, it will provide a foundation to understand the role of adaptive immunity in bat antiviral responses. PMID:27183594

  11. Analysis of endogenous peptides bound by soluble MHC class I molecules: a novel approach for identifying tumor-specific antigens.

    Science.gov (United States)

    Barnea, Eilon; Beer, Ilan; Patoka, Renana; Ziv, Tamar; Kessler, Ofra; Tzehoval, Esther; Eisenbach, Lea; Zavazava, Nicholas; Admon, Arie

    2002-01-01

    The Human MHC Project aims at comprehensive cataloging of peptides presented within the context of different human leukocyte antigens (HLA) expressed by cells of various tissue origins, both in health and in disease. Of major interest are peptides presented on cancer cells, which include peptides derived from tumor antigens that are of interest for immunotherapy. Here, HLA-restricted tumor-specific antigens were identified by transfecting human breast, ovarian and prostate tumor cell lines with truncated genes of HLA-A2 and HLA-B7. Soluble HLA secreted by these cell lines were purified by affinity chromatography and analyzed by nano-capillary electrospray ionization-tandem mass spectrometry. Typically, a large peptide pool was recovered and sequenced including peptides derived from MAGE-B2 and mucin and other new tumor-derived antigens that may serve as potential candidates for immunotherapy. PMID:11782012

  12. Co-expression of tumor antigen and interleukin-2 from an adenoviral vector augments the efficiency of therapeutic tumor vaccination

    DEFF Research Database (Denmark)

    Jensen, Benjamin Anderschou Holbech; Steffensen, Maria Abildgaard; Nørgaard Nielsen, Karen;

    2014-01-01

    approach where the target antigen fused to Ii is expressed from the adenoviral E1 region and IL-2 is expressed from the E3 region. Immunization of mice with this new vector construct resulted in an augmented primary effector CD8+ T-cell response. Furthermore, in a melanoma model we observed significantly...... prolonged tumor control in vaccinated wild type (WT) mice. The improved tumor control required antigen-specific cells, since no tumor control was observed, unless the melanoma cells expressed the vaccine targeted antigen. We also tested our new vaccine in immunodeficient (CD80/86 deficient) mice. Following...

  13. Development and evaluation of two subunit vaccine candidates containing antigens of hepatitis E virus, rotavirus, and astrovirus

    Science.gov (United States)

    Xia, Ming; Wei, Chao; Wang, Leyi; Cao, Dianjun; Meng, Xiang-Jin; Jiang, Xi; Tan, Ming

    2016-01-01

    Hepatitis E virus (HEV), rotavirus (RV), and astrovirus (AstV) are important pathogens that transmit through a common fecal-oral route, causing hepatitis (HEV) and gastroenteritis (RV and AstV) respectively in humans. In this study, we developed and evaluated two subunit vaccine candidates that consisted of the same protruding or spike protein antigens of the three viruses in two formats, a fusion of the three antigens into one molecule (fused vaccine) vs. a mixture of the three free antigens together (mixed vaccine). Both vaccines were easily made via E. coli expression system. Mouse immunization experiments showed that the fused vaccine elicited significantly higher antibody responses against the three viral antigens than those induced by the mixed vaccine. In addition, the mouse post-immune antisera of the fused vaccine revealed significantly higher neutralizing titers against HEV infection in cell culture, as well as significantly higher 50% blocking titers (BT50) against RV VP8-HBGA receptor interactions than those of the post-immune antisera after immunization of the mixed vaccine. Thus, the fused vaccine is a promising trivalent vaccine candidate against HEV, RV, and AstV, which is worth for further development. PMID:27194006

  14. Development and evaluation of two subunit vaccine candidates containing antigens of hepatitis E virus, rotavirus, and astrovirus.

    Science.gov (United States)

    Xia, Ming; Wei, Chao; Wang, Leyi; Cao, Dianjun; Meng, Xiang-Jin; Jiang, Xi; Tan, Ming

    2016-01-01

    Hepatitis E virus (HEV), rotavirus (RV), and astrovirus (AstV) are important pathogens that transmit through a common fecal-oral route, causing hepatitis (HEV) and gastroenteritis (RV and AstV) respectively in humans. In this study, we developed and evaluated two subunit vaccine candidates that consisted of the same protruding or spike protein antigens of the three viruses in two formats, a fusion of the three antigens into one molecule (fused vaccine) vs. a mixture of the three free antigens together (mixed vaccine). Both vaccines were easily made via E. coli expression system. Mouse immunization experiments showed that the fused vaccine elicited significantly higher antibody responses against the three viral antigens than those induced by the mixed vaccine. In addition, the mouse post-immune antisera of the fused vaccine revealed significantly higher neutralizing titers against HEV infection in cell culture, as well as significantly higher 50% blocking titers (BT50) against RV VP8-HBGA receptor interactions than those of the post-immune antisera after immunization of the mixed vaccine. Thus, the fused vaccine is a promising trivalent vaccine candidate against HEV, RV, and AstV, which is worth for further development. PMID:27194006

  15. Genetic diversity and population structure of genes encoding vaccine candidate antigens of Plasmodium vivax

    Directory of Open Access Journals (Sweden)

    Chenet Stella M

    2012-03-01

    Full Text Available Abstract Background A major concern in malaria vaccine development is genetic polymorphisms typically observed among Plasmodium isolates in different geographical areas across the world. Highly polymorphic regions have been observed in Plasmodium falciparum and Plasmodium vivax antigenic surface proteins such as Circumsporozoite protein (CSP, Duffy-binding protein (DBP, Merozoite surface protein-1 (MSP-1, Apical membrane antigen-1 (AMA-1 and Thrombospondin related anonymous protein (TRAP. Methods Genetic variability was assessed in important polymorphic regions of various vaccine candidate antigens in P. vivax among 106 isolates from the Amazon Region of Loreto, Peru. In addition, genetic diversity determined in Peruvian isolates was compared to population studies from various geographical locations worldwide. Results The structured diversity found in P. vivax populations did not show a geographic pattern and haplotypes from all gene candidates were distributed worldwide. In addition, evidence of balancing selection was found in polymorphic regions of the trap, dbp and ama-1 genes. Conclusions It is important to have a good representation of the haplotypes circulating worldwide when implementing a vaccine, regardless of the geographic region of deployment since selective pressure plays an important role in structuring antigen diversity.

  16. Evaluation of Salmonella enterica type III secretion system effector proteins as carriers for heterologous vaccine antigens.

    Science.gov (United States)

    Hegazy, Wael Abdel Halim; Xu, Xin; Metelitsa, Leonid; Hensel, Michael

    2012-03-01

    Live attenuated strains of Salmonella enterica have a high potential as carriers of recombinant vaccines. The type III secretion system (T3SS)-dependent translocation of S. enterica can be deployed for delivery of heterologous antigens to antigen-presenting cells. Here we investigated the efficacy of various effector proteins of the Salmonella pathogenicity island (SPI2)-encoded T3SS for the translocation of model antigens and elicitation of immune responses. The SPI2 T3SS effector proteins SifA, SteC, SseL, SseJ, and SseF share an endosomal membrane-associated subcellular localization after translocation. We observed that all effector proteins could be used to translocate fusion proteins with the model antigens ovalbumin and listeriolysin into the cytosol of host cells. Under in vitro conditions, fusion proteins with SseJ and SteC stimulated T-cell responses that were superior to those triggered by fusion proteins with SseF. However, in mice vaccinated with Salmonella carrier strains, only fusion proteins based on SseJ or SifA elicited potent T-cell responses. These data demonstrate that the selection of an optimal SPI2 effector protein for T3SS-mediated translocation is a critical parameter for the rational design of effective Salmonella-based recombinant vaccines.

  17. A peptide mimic blocks the cross-reaction of anti-DNA antibodies with glomerular antigens.

    Science.gov (United States)

    Xia, Y; Eryilmaz, E; Der, E; Pawar, R D; Guo, X; Cowburn, D; Putterman, C

    2016-03-01

    Anti-DNA antibodies play a pivotal role in the pathogenesis of lupus nephritis by cross-reacting with renal antigens. Previously, we demonstrated that the binding affinity of anti-DNA antibodies to self-antigens is isotype-dependent. Furthermore, significant variability in renal pathogenicity was seen among a panel of anti-DNA isotypes [derived from a single murine immunoglobulin (Ig)G3 monoclonal antibody, PL9-11] that share identical variable regions. In this study, we sought to select peptide mimics that effectively inhibit the binding of all murine and human anti-DNA IgG isotypes to glomerular antigens. The PL9-11 panel of IgG anti-DNA antibodies (IgG1, IgG2a, IgG2b and IgG3) was used for screening a 12-mer phage display library. Binding affinity was determined by surface plasmon resonance. Enzyme-linked immunosorbent assay (ELISA), flow cytometry and glomerular binding assays were used for the assessment of peptide inhibition of antibody binding to nuclear and kidney antigens. We identified a 12 amino acid peptide (ALWPPNLHAWVP, or 'ALW') which binds to all PL9-11 IgG isotypes. Preincubation with the ALW peptide reduced the binding of the PL9-11 anti-DNA antibodies to DNA, laminin, mesangial cells and isolated glomeruli significantly. Furthermore, we confirmed the specificity of the amino acid sequence in the binding of ALW to anti-DNA antibodies by alanine scanning. Finally, ALW inhibited the binding of murine and human lupus sera to dsDNA and glomeruli significantly. In conclusion, by inhibiting the binding of polyclonal anti-DNA antibodies to autoantigens in vivo, the ALW peptide (or its derivatives) may potentially be a useful approach to block anti-DNA antibody binding to renal tissue.

  18. Cattle tick vaccines: many candidate antigens, but will a commercially viable product emerge?

    Science.gov (United States)

    Guerrero, Felix D; Miller, Robert J; Pérez de León, Adalberto A

    2012-05-01

    The cattle tick, Rhipicephalus microplus, is arguably the world's most economically important external parasite of cattle. Sustainable cattle tick control strategies are required to maximise the productivity of cattle in both large production operations and small family farms. Commercially available synthetic acaricides are commonly used in control and eradication programs, but indiscriminate practices in their application have resulted in the rapid evolution of resistance among populations in tropical and subtropical regions where the invasive R. microplus thrives. The need for novel technologies that could be used alone or in combination with commercially available synthetic acaricides is driving a resurgence of cattle tick vaccine discovery research efforts by various groups globally. The aim is to deliver a next-generation vaccine that has an improved efficacy profile over the existing Bm86-based cattle tick vaccine product. We present a short review of these projects and offer our opinion on what constitutes a good target antigen and vaccine, and what might influence the market success of candidate vaccines. The previous experience with Bm86-based vaccines offers perspective on marketing and producer acceptance aspects that a next-generation cattle tick vaccine product must meet for successful commercialisation. PMID:22549026

  19. Antigenic peptide trimming by ER aminopeptidases--insights from structural studies.

    Science.gov (United States)

    Stratikos, Efstratios; Stern, Lawrence J

    2013-10-01

    Generation and destruction of antigenic peptides by ER resident aminopeptidases ERAP1 and ERAP2 have been shown in the last few years to be important for the correct functioning and regulation of the adaptive immune response. These two highly homologous aminopeptidases appear to have evolved complex mechanisms well suited for their biological role in antigen presentation. Furthermore, polymorphic variability in these enzymes appears to affect their function and predispose individuals to disease. This review discusses our current understanding of the molecular mechanisms behind ERAP1/2 function as suggested by several recently determined crystallographic structures of these enzymes. PMID:23545452

  20. Phase I clinical trial of the vaccination for the patients with metastatic melanoma using gp100-derived epitope peptide restricted to HLA-A*2402

    Directory of Open Access Journals (Sweden)

    Baba Toshiyuki

    2010-09-01

    Full Text Available Abstract Background The tumor associated antigen (TAA gp100 was one of the first identified and has been used in clinical trials to treat melanoma patients. However, the gp100 epitope peptide restricted to HLA-A*2402 has not been extensively examined clinically due to the ethnic variations. Since it is the most common HLA Class I allele in the Japanese population, we performed a phase I clinical trial of cancer vaccination using the HLA-A*2402 gp100 peptide to treat patients with metastatic melanoma. Methods The phase I clinical protocol to test a HLA-A*2402 gp100 peptide-based cancer vaccine was designed to evaluate safety as the primary endpoint and was approved by The University of Tokyo Institutional Review Board. Information related to the immunologic and antitumor responses were also collected as secondary endpoints. Patients that were HLA-A*2402 positive with stage IV melanoma were enrolled according to the criteria set by the protocol and immunized with a vaccine consisting of epitope peptide (VYFFLPDHL, gp100-in4 emulsified with incomplete Freund's adjuvant (IFA for the total of 4 times with two week intervals. Prior to each vaccination, peripheral blood mononuclear cells (PBMCs were separated from the blood and stored at -80°C. The stored PBMCs were thawed and examined for the frequency of the peptide specific T lymphocytes by IFN-γ- ELISPOT and MHC-Dextramer assays. Results No related adverse events greater than grade I were observed in the six patients enrolled in this study. No clinical responses were observed in the enrolled patients although vitiligo was observed after the vaccination in two patients. Promotion of peptide specific immune responses was observed in four patients with ELISPOT assay. Furthermore, a significant increase of CD8+ gp100-in4+ CTLs was observed in all patients using the MHC-Dextramer assay. Cytotoxic T lymphocytes (CTLs clones specific to gp100-in4 were successfully established from the PBMC of some

  1. Reduced antibody responses against Plasmodium falciparum vaccine candidate antigens in the presence of Trichuris trichiura

    DEFF Research Database (Denmark)

    Esen, Meral; Mordmüller, Benjamin; de Salazar, Pablo Martinez;

    2012-01-01

    antigens and parasitological status were assessed. Vaccine-specific antibody concentrations and memory B-cell numbers were compared in worm infected and non-infected participants. RESULTS: Antibody response to GMZ2 was 3.4-fold (95% confidence interval: 1.6, 7.4) higher in Trichuris trichiura negative...... subjects compared to positive participants, whereas immunoglobulin subclass distribution was similar. Memory B-cell response was moderately increased in T. trichiura negative individuals, although the difference was not significant. CONCLUSIONS: Future malaria vaccine development programs need to account...

  2. PLAP efficiently generates mature antigenic peptides in vitro but in patterns distinct from ERAP11

    OpenAIRE

    Georgiadou, Dimitra; Hearn, Arron; Evnouchidou, Irini; Chroni, Angeliki; Leondiadis, Leondios; Ian A York; Rock, Kenneth L.; Stratikos, Efstratios

    2010-01-01

    All three members of the oxytocinase sub-family of M1 aminopeptidases, ERAP1 (ERAAP), ERAP2 and PLAP (IRAP), have been implicated in the generation of MHC class I-presented peptides. ERAP1 and 2 trim peptides in the endoplasmic reticulum for direct presentation whereas PLAP has been recently implicated in cross presentation. The best characterized member of the family, ERAP1, has unique enzymatic properties that fit well with its role in antigen processing. ERAP1 can trim a large variety of l...

  3. Vaccination of pigs with Toxoplasma gondii antigens incorporated in immunostimulating complexes (iscoms)

    OpenAIRE

    Freire R.L.; Navarro I.T.; Bracarense A.P.F.R.L.; Gennari S.M.

    2003-01-01

    Immunity to Toxoplasma gondii was studied in pigs, after vaccination with T. gondii antigens incorporated into immunostimulating complexes. Nine pigs (group 1 - G1) were inoculated subcutaneously with T. gondii iscoms (LIV-5 sample) and three doses were given at 21 and 13 day-intervals. The results were compared in other three groups of nine pigs each: animals in group 2 (G2) were immunized with the LIV-5 antigens without Quil A, animals in group 3 (G3) were inoculated with tachyzoites of RH ...

  4. Applying the Concept of Peptide Uniqueness to Anti-Polio Vaccination

    Directory of Open Access Journals (Sweden)

    Darja Kanduc

    2015-01-01

    Full Text Available Background. Although rare, adverse events may associate with anti-poliovirus vaccination thus possibly hampering global polio eradication worldwide. Objective. To design peptide-based anti-polio vaccines exempt from potential cross-reactivity risks and possibly able to reduce rare potential adverse events such as the postvaccine paralytic poliomyelitis due to the tendency of the poliovirus genome to mutate. Methods. Proteins from poliovirus type 1, strain Mahoney, were analyzed for amino acid sequence identity to the human proteome at the pentapeptide level, searching for sequences that (1 have zero percent of identity to human proteins, (2 are potentially endowed with an immunologic potential, and (3 are highly conserved among poliovirus strains. Results. Sequence analyses produced a set of consensus epitopic peptides potentially able to generate specific anti-polio immune responses exempt from cross-reactivity with the human host. Conclusion. Peptide sequences unique to poliovirus proteins and conserved among polio strains might help formulate a specific and universal anti-polio vaccine able to react with multiple viral strains and exempt from the burden of possible cross-reactions with human proteins. As an additional advantage, using a peptide-based vaccine instead of current anti-polio DNA vaccines would eliminate the rare post-polio poliomyelitis cases and other disabling symptoms that may appear following vaccination.

  5. Cancer testis antigen and immunotherapy

    Directory of Open Access Journals (Sweden)

    Krishnadas DK

    2013-04-01

    Full Text Available Deepa Kolaseri Krishnadas, Fanqi Bai, Kenneth G Lucas Department of Pediatrics, Division of Hematology/Oncology, University of Louisville, KY, USA Abstract: The identification of cancer testis (CT antigens has been an important advance in determining potential targets for cancer immunotherapy. Multiple previous studies have shown that CT antigen vaccines, using both peptides and dendritic cell vaccines, can elicit clinical and immunologic responses in several different tumors. This review details the expression of melanoma antigen family A, 1 (MAGE-A1, melanoma antigen family A, 3 (MAGE-A3, and New York esophageal squamous cell carcinoma-1 (NY-ESO-1 in various malignancies, and presents our current understanding of CT antigen based immunotherapy. Keywords: cancer testis antigens, immunotherapy, vaccine

  6. Multiple antigen peptide dendrimer elicits antibodies for detecting rat and mouse growth hormone binding proteins

    OpenAIRE

    Aguilar, Roberto M.; Talamantes, Frank J.; Bustamante, Juan J.; Muñoz, Jesus; Treviño, Lisa R.; Martinez, Andrew O.; Haro, Luis S.

    2009-01-01

    The membrane-bound rat growth hormone receptor (GH-R) and an alternatively spliced isoform, the soluble rat GH binding protein (GH-BP), are comprised of identical N-terminal GH binding domains, however, their C-terminal sequences differ. Immunological reagents are needed to distinguish between the two isoforms in order to understand their respective roles in mediating the actions of GH. Accordingly, a tetravalent multiple antigen peptide (MAP) dendrimer with four identical branches of a C-ter...

  7. Defining the antigenic diversity of Plasmodium falciparum apical membrane antigen 1 and the requirements for a multi-allele vaccine against malaria.

    Directory of Open Access Journals (Sweden)

    Damien R Drew

    Full Text Available Apical Membrane Antigen 1 (AMA1 is a leading malaria vaccine candidate and a target of naturally-acquired human immunity. Plasmodium falciparum AMA1 is polymorphic and in vaccine trials it induces strain-specific protection. This antigenic diversity is a major roadblock to development of AMA1 as a malaria vaccine and understanding how to overcome it is essential. To assess how AMA1 antigenic diversity limits cross-strain growth inhibition, we assembled a panel of 18 different P. falciparum isolates which are broadly representative of global AMA1 sequence diversity. Antibodies raised against four well studied AMA1 alleles (W2Mef, 3D7, HB3 and FVO were tested for growth inhibition of the 18 different P. falciparum isolates in growth inhibition assays (GIA. All antibodies demonstrated substantial cross-inhibitory activity against different isolates and a mixture of the four different AMA1 antibodies inhibited all 18 isolates tested, suggesting significant antigenic overlap between AMA1 alleles and limited antigenic diversity of AMA1. Cross-strain inhibition by antibodies was only moderately and inconsistently correlated with the level of sequence diversity between AMA1 alleles, suggesting that sequence differences are not a strong predictor of antigenic differences or the cross-inhibitory activity of anti-allele antibodies. The importance of the highly polymorphic C1-L region for inhibitory antibodies and potential vaccine escape was assessed by generating novel transgenic P. falciparum lines for testing in GIA. While the polymorphic C1-L epitope was identified as a significant target of some growth-inhibitory antibodies, these antibodies only constituted a minor proportion of the total inhibitory antibody repertoire, suggesting that the antigenic diversity of inhibitory epitopes is limited. Our findings support the concept that a multi-allele AMA1 vaccine would give broad coverage against the diversity of AMA1 alleles and establish new tools to

  8. Merozoite Surface Antigen 2 Proteins of Babesia bovis Vaccine Breakthrough Isolates Contain a Unique Hypervariable Region Composed of Degenerate Repeats

    OpenAIRE

    Berens, Shawn J.; Brayton, Kelly A.; Molloy, John B.; Bock, Russell E.; Lew, Ala E.; McElwain, Terry F.

    2005-01-01

    The merozoite surface antigen 2 (MSA-2) proteins of Babesia bovis are members of the variable merozoite surface antigen (VMSA) family that have been implicated in erythrocyte invasion and are important targets for antibody-mediated blocking of invasion. Extensive sequence variation in another VMSA member, MSA-1, has been shown in all vaccine breakthrough isolates. To test the hypothesis that the msa-2 genes of vaccine breakthrough isolates would also encode a diverse set of proteins, the comp...

  9. Human Leukocyte Antigens Influence the Antibody Response to Hepatitis B Vaccine

    Directory of Open Access Journals (Sweden)

    Abdollah Jafarzadeh

    2015-10-01

    Full Text Available Hepatitis B virus (HBV infection and its sequelae such as cirrhosis and hepatocellular carcinoma has remained a serious public health problem throughout the world. The WHO strategy for effective control of HBV infection and its complications is mass vaccination of neonates and children within the framework of Expanded Programme on Immunization (EPI. Vaccination with hepatitis B surface antigen (HBsAg induces protective antibody response (anti-HBs ≥ 10 IU/L in 90-99% of vaccinees.The lack of  response to  HBsAg has  been attributed  to a variety of  immunological mechanisms, including defect in antigen presentation, defect in HBsAg-specific T and/or B cell repertoires, T-cell suppression, increase in the regulatory T cell count, lack of necessary help of T-cells for production of anti-HBs by B cells, defect in Th1 and/or Th2 cytokine production  and  selective  killing  of  HBsAg-specific  B-cells  by  human  leukocyte  antigen (HLA-restricted cytotoxic T lymphocytes. The HLA complex plays an important role in many of these immunological processes.A variety of HLA class I, II, and III alleles and antigens have been reported to beassociated with antibody response to HBsAg vaccination in different ethnic populations. Moreover, some HLA haplotypes were also associated with responsiveness to HBsAg.In this review the association of the HLA specificities with antibody response to hepatitis B (HB vaccine is discussed.

  10. Chloroplast-Derived Vaccine Antigens and Biopharmaceuticals: Expression, Folding, Assembly and Functionality

    OpenAIRE

    Chebolu, S.; Daniell, H

    2009-01-01

    Chloroplast genetic engineering offers several advantages, including high levels of transgene expression, transgene containment via maternal inheritance, and multi-gene expression in a single transformation event. Oral delivery is facilitated by hyperexpression of vaccine antigens against cholera, tetanus, anthrax, plague, or canine parvovirus (4%–31% of total soluble protein, TSP) in transgenic chloroplasts (leaves) or non-green plastids (carrots, tomato) as well as the availability of antib...

  11. Engineering the chloroplast targeted malarial vaccine antigens in Chlamydomonas starch granules.

    Directory of Open Access Journals (Sweden)

    David Dauvillée

    Full Text Available BACKGROUND: Malaria, an Anopheles-borne parasitic disease, remains a major global health problem causing illness and death that disproportionately affects developing countries. Despite the incidence of malaria, which remains one of the most severe infections of human populations, there is no licensed vaccine against this life-threatening disease. In this context, we decided to explore the expression of Plasmodium vaccine antigens fused to the granule bound starch synthase (GBSS, the major protein associated to the starch matrix in all starch-accumulating plants and algae such as Chlamydomonas reinhardtii. METHODS AND FINDINGS: We describe the development of genetically engineered starch granules containing plasmodial vaccine candidate antigens produced in the unicellular green algae Chlamydomonas reinhardtii. We show that the C-terminal domains of proteins from the rodent Plasmodium species, Plasmodium berghei Apical Major Antigen AMA1, or Major Surface Protein MSP1 fused to the algal granule bound starch synthase (GBSS are efficiently expressed and bound to the polysaccharide matrix. Mice were either immunized intraperitoneally with the engineered starch particles and Freund adjuvant, or fed with the engineered particles co-delivered with the mucosal adjuvant, and challenged intraperitoneally with a lethal inoculum of P. Berghei. Both experimental strategies led to a significantly reduced parasitemia with an extension of life span including complete cure for intraperitoneal delivery as assessed by negative blood thin smears. In the case of the starch bound P. falciparum GBSS-MSP1 fusion protein, the immune sera or purified immunoglobulin G of mice immunized with the corresponding starch strongly inhibited in vitro the intra-erythrocytic asexual development of the most human deadly plasmodial species. CONCLUSION: This novel system paves the way for the production of clinically relevant plasmodial antigens as algal starch-based particles

  12. Structural Basis For Antigenic Peptide Precursor Processing by the Endoplasmic Reticulum Aminopeptidase ERAP1

    Energy Technology Data Exchange (ETDEWEB)

    T Nguyen; S Chang; I Evnouchidou; I York; C Zikos; K Rock; A Goldberg; E Stratikos; L Stern

    2011-12-31

    ERAP1 trims antigen precursors to fit into MHC class I proteins. To fulfill this function, ERAP1 has unique substrate preferences, trimming long peptides but sparing shorter ones. To identify the structural basis for ERAP1's unusual properties, we determined the X-ray crystal structure of human ERAP1 bound to bestatin. The structure reveals an open conformation with a large interior compartment. An extended groove originating from the enzyme's catalytic center can accommodate long peptides and has features that explain ERAP1's broad specificity for antigenic peptide precursors. Structural and biochemical analyses suggest a mechanism for ERAP1's length-dependent trimming activity, whereby binding of long rather than short substrates induces a conformational change with reorientation of a key catalytic residue toward the active site. ERAP1's unique structural elements suggest how a generic aminopeptidase structure has been adapted for the specialized function of trimming antigenic precursors.

  13. Protection of Mice with a Divalent Tuberculosis DNA Vaccine Encoding Antigens Ag85B and MPT64

    Institute of Scientific and Technical Information of China (English)

    Xia TIAN; Hong CAI; Yu-Xian ZHU

    2004-01-01

    DNA vaccine may be a promising tool for controlling tuberculosis development. However,vaccines encoding single antigens of mycobacterium did not produce protective effect as BCG did. In the present study, we evaluated the immunogenicity and protective efficacy of a divalent DNA vaccine encoding two immunodominant antigens Ag85B and MPT64 of Mycobacterium tuberculosis. We found that both humoral and Th1-type (high IFN-γ, low IL-4) cellular responses obtained from the divalent DNA vaccine group were significantly higher than that conferred by BCG. RT-PCR results showed that antigens were expressed differentially in various organs in divalent DNA vaccine group. The survival rate for mice treated with the divalent DNA vaccine after challenging with high doses of virulent M. tuberculosis H37Rv was significantly higher than that of the BCG group or any of the single DNA vaccine group. Significant differences were also found between the single and divalent DNA vaccinated mice in terms of body, spleen and lung weight. Bacterial loading decreased about 2000-fold in lungs and about 100-fold in spleens of divalent DNA vaccinated mice when compared with that of the control group. We conclude that our divalent DNA vaccine may be a better choice for controlling tuberculosis disease in animals.

  14. Production of a Shigella sonnei Vaccine Based on Generalized Modules for Membrane Antigens (GMMA, 1790GAHB.

    Directory of Open Access Journals (Sweden)

    Christiane Gerke

    Full Text Available Recently, we developed a high yield production process for outer membrane particles from genetically modified bacteria, called Generalized Modules of Membrane Antigens (GMMA, and the corresponding simple two step filtration purification, enabling economic manufacture of these particles for use as vaccines. Using a Shigella sonnei strain that was genetically modified to produce penta-acylated lipopolysaccharide (LPS with reduced endotoxicity and to maintain the virulence plasmid encoding for the immunodominant O antigen component of the LPS, scale up of the process to GMP pilot scale was straightforward and gave high yields of GMMA with required purity and consistent results. GMMA were formulated with Alhydrogel and were highly immunogenic in mice and rabbits. In mice, a single immunization containing 29 ng protein and 1.75 ng of O antigen elicited substantial anti-LPS antibody levels. As GMMA contain LPS and lipoproteins, assessing potential reactogenicity was a key aspect of vaccine development. In an in vitro monocyte activation test, GMMA from the production strain showed a 600-fold lower stimulatory activity than GMMA with unmodified LPS. Two in vivo tests confirmed the low potential for reactogenicity. We established a modified rabbit pyrogenicity test based on the European Pharmacopoeia pyrogens method but using intramuscular administration of the full human dose (100 μg of protein. The vaccine elicited an average temperature rise of 0.5°C within four hours after administration, which was considered acceptable and showed that the test is able to detect a pyrogenic response. Furthermore, a repeat dose toxicology study in rabbits using intramuscular (100 μg/dose, intranasal (80 μg/dose, and intradermal (10 μg/dose administration routes showed good tolerability of the vaccine by all routes and supported its suitability for use in humans. The S. sonnei GMMA vaccine is now in Phase 1 dose-escalation clinical trials.

  15. Control of Boophilus microplus populations in grazing cattle vaccinated with a recombinant Bm86 antigen preparation.

    Science.gov (United States)

    Rodríguez, M; Penichet, M L; Mouris, A E; Labarta, V; Luaces, L L; Rubiera, R; Cordovés, C; Sánchez, P A; Ramos, E; Soto, A

    1995-04-01

    Current methods for the control of cattle tick Boophilus microplus infestations are not effective and the parasite remains a serious problem for the cattle industry in tropical and subtropical areas. Recently, we developed a vaccine against B. microplus employing a recombinant Bm86 (rBm86) antigen preparation (Gavac, Heber Biotec) and it was shown to induce a protective response in vaccinated animals under controlled conditions. Here we show that, under field conditions in grazing cattle, the vaccine is able to control B. microplus populations. Two parasite-free farms were employed for the study. In the first farm, animals were vaccinated with the recombinant vaccine, while, in the second, animals received a saline injection in adjuvant. After immunization, animals were artificially infected and the infestation rate was recorded. Over the 33 weeks of the experiment, the infestation rate was lower in the vaccinated group compared with the control group. At the end of the experiment it was necessary to use chemicals in the control farm after serious losses in production and animals. PMID:7660571

  16. Vaccination with a cocktail of Ancylostoma ceylanicum recombinant antigens leads to worm burden reduction in hamsters.

    Science.gov (United States)

    Wiśniewski, Marcin; Łapiński, Maciej; Daniłowicz-Luebert, Emilia; Jaros, Sławomir; Długosz, Ewa; Wędrychowicz, Halina

    2016-09-01

    Hookworms, a group to which Ancylostoma ceylanicum belongs, are gastrointestinal nematodes that infect more than 700 million people around the world. They are a leading cause of anemia in developing countries. In order to effectively prevent hookworm infections research is conducted to develop an effective vaccine using recombinant antigens of the parasite. The aim of this study was to examine the influence of the hosts' on protection against ancylostomiasis and the shaping of the humoral immune response among Syrian hamsters after immunization with a cocktail of five A. ceylanicum recombinant antigens. Ace-ASP-3, Ace-ASP-4, Ace-APR-1, Ace-MEP-6 and Ace-MEP-7 were obtained in the pET expression system. Immunization with a vaccine cocktail resulted in a 33.5% worm burden reduction. The immunogenicity of the recombinant proteins were determined using ELISA. Statistical analysis showed that vaccinated hamsters developed stronger humoral responses to four of five recombinant antigens (the exception being Ace-ASP-3) compared to hamsters from the control group. PMID:27447220

  17. Pentamers Not Found in the Universal Proteome Can Enhance Antigen Specific Immune Responses and Adjuvant Vaccines

    OpenAIRE

    Ami Patel; Dong, Jessica C.; Brett Trost; Richardson, Jason S.; Sarah Tohme; Shawn Babiuk; Anthony Kusalik; Kung, Sam K. P.; Kobinger, Gary P.

    2012-01-01

    Certain short peptides do not occur in humans and are rare or non-existent in the universal proteome. Antigens that contain rare amino acid sequences are in general highly immunogenic and may activate different arms of the immune system. We first generated a list of rare, semi-common, and common 5-mer peptides using bioinformatics tools to analyze the UniProtKB database. Experimental observations indicated that rare and semi-common 5-mers generated stronger cellular responses in comparison wi...

  18. Active immunizations with peptide-DC vaccines and passive transfer with antibodies protect neutropenic mice against disseminated candidiasis.

    Science.gov (United States)

    Xin, Hong

    2016-01-01

    We previously report that peptide-pulsed dendritic cell (DC) vaccination, which targeting two peptides (Fba and Met6) expressed on the cell surface of Candida albicans, can induce high degree of protection against disseminated candidiasis in immunocompetent mice. Passive transfer of immune sera from the peptide immunized mice or peptide-related monoclonal antibodies demonstrated that protection was medicated by peptide-specific antibodies. In this study the efficacy of active and passive immunization against disseminated candidiasis was tested in mice with cyclophosphamide-induced neutropenia. Peptide-DC vaccines were given to mice prior to induction of neutropenia. We show active immunization with either Fba or Met6 peptide-DC vaccine significantly improved the survival and reduced the fungal burden of disseminated candidiasis in those immunocompromised mice. Importantly, we show that administration of two protective monoclonal antibodies also protect neutropenic mice against the disease, implying possibility of developing a successful passive immunotherapy strategy to treat the disease and protect against disseminated candidiasis. The results of this study are crucial as they address the fundamental questions as to whether the synthetic peptide vaccine induced immunity protects the host during a neutropenic episode. We anticipate that this peptide-vaccine study will serve as the foundation of future investigations into new peptide vaccines comprised of cell surface peptides from other medically important Candida species, as well as other fungi.

  19. TSOL18 Vaccine Antigen of Taenia solium: Development of Monoclonal Antibodies and Field Testing of the Vaccine in Cameroon

    Directory of Open Access Journals (Sweden)

    Assana, E.

    2010-01-01

    Full Text Available Chapter 1 reviews the literature about the immunological aspects of taeniid cestode infections and the existing vaccines against Taenia solium cysticercosis in pigs. One of the most promising vaccines is TSOL18, a protein that has been identified in the oncosphere of Taenia solium and expressed as a recombinant molecule in E. coli. Repeated experimental trials have shown that this vaccine is able to protect up to 100% of the immunised pigs against a challenge infection with T. solium. Antibodies raised by the vaccine are capable of killing the parasite in in vitro cultures and it is believed that antibody and complement mediated killing of invading parasites is the major protective immune mechanism induced by vaccination with TSOL18. The identification of the villages with a high risk of T. solium infection, which could subsequently be used in the vaccine trial, is reported in chapter 2. A survey was conducted in 150 households owning 1756 pigs in the rural areas of Mayo-Danay division in the far north region of Cameroon. A questionnaire survey was carried out to collect information on the pig farming system and to identify potential risk factors for T. solium cysticercosis infection in pigs. Blood samples were collected from 398 pigs with the aim of estimating the sero-prevalence of Taenia solium cysticercosis. The results showed that 90.7% of the pigs were free roaming during the dry season and that 42.7% of households keeping pigs in the rural areas had no latrine facility. Seventy six percent of the interviewed pig owners affirmed that the members of the household used open field defecation. ELISA for antigen and antibody detection showed an apparent prevalence of porcine cysticercosis of 24.6% and 32.2%, respectively. A Bayesian approach using the conditional dependence between the two diagnostic tests indicated that the true sero-prevalence of cysticercosis in Mayo-Danay was 26.6%. Binary logistic regression analysis indicated that the

  20. Proteomic study via a non-gel based approach of meningococcal outer membrane vesicle vaccine obtained from strain CU385: a road map for discovering new antigens.

    Science.gov (United States)

    Gil, Jeovanis; Betancourt, L Zaro H; Sardiñas, Gretel; Yero, Daniel; Niebla, Olivia; Delgado, Maité; García, Darien; Pajón, Rolando; Sánchez, Aniel; González, Luis J; Padrón, Gabriel; Campa, Concepción; Sotolongo, Franklin; Barberó, Ramón; Guillén, Gerardo; Herrera, Luis; Besada, Vladimir

    2009-05-01

    This work presents the results from a study of the protein composition of outer membrane vesicles from VA-MENGOC-BC (Finlay Institute, Cuba), an available vaccine against serogroup B Neisseria meningitidis. Proteins were identified by means of SCAPE, a 2DE-free method for proteome studies. More than one hundred proteins were detected by tandem liquid chromatographymass spectrometry analysis of fractions enriched in peptides devoid of histidine or arginine residues, providing a detailed description of the vaccine. A bioinformatic analysis of the identified components resulted in the identification of 31 outer membrane proteins and three conserved hypothetical proteins, allowing the cloning, expression, purification and immunological study of two of them (NMB0088 and NMB1796) as new antigens.

  1. Targeting of non-dominant antigens as a vaccine strategy to broaden T-cell responses during chronic viral infection

    DEFF Research Database (Denmark)

    Holst, Peter Johannes; Jensen, Benjamin Anderschou Holbech; Ragonnaud, Emeline;

    2015-01-01

    challenge with live virus, the CD8+ T cells specific for vaccine-encoded epitopes, displayed a phenotype typically associated with prolonged/persistent antigenic stimulation marked by high levels of KLRG-1, as compared to T cells reacting to epitopes not included in the vaccine. Notably, this association...

  2. Vaccination of pigs with Toxoplasma gondii antigens incorporated in immunostimulating complexes (iscoms

    Directory of Open Access Journals (Sweden)

    Freire R.L.

    2003-01-01

    Full Text Available Immunity to Toxoplasma gondii was studied in pigs, after vaccination with T. gondii antigens incorporated into immunostimulating complexes. Nine pigs (group 1 - G1 were inoculated subcutaneously with T. gondii iscoms (LIV-5 sample and three doses were given at 21 and 13 day-intervals. The results were compared in other three groups of nine pigs each: animals in group 2 (G2 were immunized with the LIV-5 antigens without Quil A, animals in group 3 (G3 were inoculated with tachyzoites of RH T. gondii isolate, and animals in group 4 (G4 received no vaccination. Four animals were neither vaccinated nor challenged with T. gondii (group 5 - G5. Thirty days after vaccination, pigs were challenged orally with 5´10(4 oocysts at AS-28 T. gondii isolate. Euthanasia was carried out 47 days after challenge and specimens of the heart, muscle, brain, liver, tongue and retina were inoculated into mice. Three out of nine pigs from G2 and one out of nine pigs from G4 showed hypertermia after the challenge. Antibody response was analysed by indirect fluorescent antibody test. The first iscom immunization (G1 induced low antibody levels, the second and third produced high antibody levels, similarly to the RH isolate infection (G3. Western blotting analysis indicated that the antibody response in animals in G1, after challenge, was more intense than in animals in the non-vaccinated group. T. gondii was not isolated by bioassays from tissues of iscom vaccinated pigs, while recovery was obtained from four animals in G4, one in G2 and one in G3.

  3. Evaluation of antigens stability of tobacco seeds as edible vaccine against VTEC strains

    Directory of Open Access Journals (Sweden)

    Luciana Rossi

    2015-11-01

    Full Text Available Plants have represent a promising alternative for biopharmaceutical proteins (Ma et al., 2003; Rossi et al., 2014. Many plant based edible vaccines have been shown to be effective in inducing local immune responses (Rossi et al., 2013. Edible vaccines can activate both mucosal and systemic immunity, as they come in contact with the digestive tract lining. This dual effect would provide first-line defense against pathogens invading through the mucosa. The antigens are released in the intestines are taken up by M cells that are present over the Payer’s patches (in the ileum and the gut associated lymphoid tissue (GALT. Edible vaccines represent an important worldwide goal for the prevention of the enteric diseases, also in livestock. In particular, the enteric infections are a significant clinical problem in pigs. Verocytotoxic Escherichia (E. coli strains are responsible for serious enterotoxaemia that causes important economic losses in the pig industry. The production of a vaccine for oral administration of transgenic seeds could be a practical and efficient system to prevent the infection and to reduce the antibiotic use. This study was focused on tobacco plants, previously transformed by agroinfection for the seed-specific expression of antigenic proteins (F18 adhesive fimbriae and the B subunit of the Vt2e toxin as model of edible vaccines against verocytotoxic E. coli strains. The dietary administration of transgenic tobacco seeds promotes a significant increase in the number of mucosal IgA-producing cells of the tunica propria in both small and large intestine in mice (Rossi et al., 2013. A protective effect of oral administration of transgenic tobacco seeds was also observed against verocytotoxic Escherichia coli infection in piglets (Rossi et al., 2014. The aim of this study was to assess the seed-expression stability, that is a important requirement in the vaccine production, of F 18 and Vt2e-B heterologous genes into the progeny of

  4. Identification of peptides from foot-and-mouth disease virus structural proteins bound by class I swine leukocyte antigen (SLA) alleles, SLA-1*0401 and SLA-2*0401.

    Science.gov (United States)

    Pedersen, L E; Harndahl, M; Nielsen, M; Patch, J R; Jungersen, G; Buus, S; Golde, W T

    2013-06-01

    Characterization of the peptide-binding specificity of swine leukocyte antigen (SLA) class I and II molecules is critical to the understanding of adaptive immune responses of swine toward infectious pathogens. Here, we describe the complete binding motif of the SLA-2*0401 molecule based on a positional scanning combinatorial peptide library approach. By combining this binding motif with data achieved by applying the NetMHCpan peptide prediction algorithm to both SLA-1*0401 and SLA-2*0401, we identified high-affinity binding peptides. A total of 727 different 9mer and 726 different 10mer peptides within the structural proteins of foot-and-mouth disease virus (FMDV), strain A24 were analyzed as candidate T-cell epitopes. Peptides predicted by the NetMHCpan were tested in ELISA for binding to the SLA-1*0401 and SLA-2*0401 major histocompatibility complex class I proteins. Four of the 10 predicted FMDV peptides bound to SLA-2*0401, whereas five of the nine predicted FMDV peptides bound to SLA-1*0401. These methods provide the characterization of T-cell epitopes in response to pathogens in more detail. The development of such approaches to analyze vaccine performance will contribute to a more accelerated improvement of livestock vaccines by virtue of identifying and focusing analysis on bona fide T-cell epitopes.

  5. Primary structure of the 175K Plasmodium falciparum erythrocyte binding antigen and identification of a peptide which elicits antibodies that inhibit malaria merozoite invasion.

    Science.gov (United States)

    Sim, B K; Orlandi, P A; Haynes, J D; Klotz, F W; Carter, J M; Camus, D; Zegans, M E; Chulay, J D

    1990-11-01

    The Plasmodium falciparum gene encoding erythrocyte binding antigen-175 (EBA-175), a putative receptor for red cell invasion (Camus, D., and T. J. Hadley. 1985. Science (Wash. DC). 230:553-556.), has been isolated and characterized. DNA sequencing demonstrated a single open reading frame encoding a translation product of 1,435 amino acid residues. Peptides corresponding to regions on the deduced amino acid sequence predicted to be B cell epitopes were assessed for immunogenicity. Immunization of mice and rabbits with EBA-peptide 4, a synthetic peptide encompassing amino acid residues 1,062-1,103, produced antibodies that recognized P. falciparum merozoites in an indirect fluorescent antibody assay. When compared to sera from rabbits immunized with the same adjuvant and carrier protein, sera from rabbits immunized with EBA-peptide 4 inhibited merozoite invasion of erythrocytes in vitro by 80% at a 1:5 dilution. Furthermore, these sera inhibited the binding of purified, authentic EBA-175 to erythrocytes, suggesting that their activity in inhibiting merozoite invasion of erythrocytes is mediated by blocking the binding of EBA-175 to erythrocytes. Since the nucleotide sequence of EBA-peptide 4 is conserved among seven strains of P. falciparum from throughout the world (Sim, B. K. L. 1990. Mol. Biochem. Parasitol. 41:293-296.), these data identify a region of the protein that should be a focus of vaccine development efforts. PMID:2229177

  6. Anthrax Vaccine Antigen-Adjuvant Formulations Completely Protect New Zealand White Rabbits against Challenge with Bacillus anthracis Ames Strain Spores

    OpenAIRE

    Peachman, Kristina K.; Li, Qin; Matyas, Gary R.; Shivachandra, Sathish B.; Lovchik, Julie; Lyons, Rick C.; Alving, Carl R; Rao, Venigalla B.; Rao, Mangala

    2012-01-01

    In an effort to develop an improved anthrax vaccine that shows high potency, five different anthrax protective antigen (PA)-adjuvant vaccine formulations that were previously found to be efficacious in a nonhuman primate model were evaluated for their efficacy in a rabbit pulmonary challenge model using Bacillus anthracis Ames strain spores. The vaccine formulations include PA adsorbed to Alhydrogel, PA encapsulated in liposomes containing monophosphoryl lipid A, stable liposomal PA oil-in-wa...

  7. Vaccine potential of recombinant antigens of Theileria annulata and Hyalomma anatolicum anatolicum against vector and parasite.

    Science.gov (United States)

    Jeyabal, L; Kumar, Binod; Ray, Debdatta; Azahahianambi, Palavesam; Ghosh, Srikanta

    2012-09-10

    In an attempt to develop vaccine against Hyalomma anatolicum anatolicum and Theileria annulata, three antigens were expressed in prokaryotic expression system and protective potentiality of the antigens was evaluated in cross bred calves. Two groups (grs. 1 and 4) of male cross-bred (Bos indicus × Bos taurus) calves were immunized with rHaa86, a Bm86 ortholog of H. a. anatolicum, while one group of calves (gr. 2) were immunized with cocktails of two antigens viz., surface antigens of T. annulata (rSPAG1, rTaSP). One group each was kept as negative controls (grs. 3 and 5). The animals of groups 1, 2 and 3 were challenged with T. annulata infected H. a. anatolicum adults while the animals of groups 1, 3, 4 and 5 were challenged with uninfected adult ticks. A significantly high (p<0.05) antibody responses to all the three antigens were detected in immunized calves, but the immune response was comparatively higher with rHaa86 followed by rTaSP and rSPAG1. Upon challenge with T. annulata infected ticks, animals of all groups showed symptoms of the disease but there was 50% survival of calves of group 1 while all non immunized control calves (group 3) and rSPAG1+rTaSP immunized calves died. The rHaa86 antigen was found efficacious to protect calves against more than 71.4-75.5% of the challenge infestation. The experiment has given a significant clue towards the development of rHaa86 based vaccine against both H. a. anatolicum and T. annulata. PMID:22546546

  8. Doubly Phosphorylated Peptide Vaccines to Protect Transgenic P301S Mice against Alzheimer’s Disease Like Tau Aggregation

    Directory of Open Access Journals (Sweden)

    Monique Richter

    2014-07-01

    Full Text Available Intracellular neurofibrillary tangles and extracellular senile plaques are potential targets for active and passive immunotherapies. In this study we used the transgenic mouse model P301S for active immunizations with peptide vaccines composed of a double phosphorylated tau neoepitope (pSer202/pThr205, pThr212/pSer214, pThr231/pSer235 and an immunomodulatory T cell epitope from the tetanus toxin or tuberculosis antigen Ag85B. Importantly, the designed vaccine combining Alzheimer’s disease (AD specific B cell epitopes with foreign (bacterial T cell epitopes induced fast immune responses with high IgG1 titers after prophylactic immunization that subsequently decreased over the observation period. The effectiveness of the immunization was surveyed by evaluating the animal behavior, as well as the pathology in the brain by biochemical and histochemical techniques. Immunized mice clearly lived longer with reduced paralysis than placebo-treated mice. Additionally, they performed significantly better in rotarod and beam walk tests at the age of 20 weeks, indicating that the disease development was slowed down. Forty-eight weeks old vaccinated mice passed the beam walk test significantly better than control animals, which together with the increased survival rates undoubtedly prove the treatment effect. In conclusion, the data provide strong evidence that active immune therapies can reduce toxic effects of deposits formed in AD.

  9. Metal based nanoparticles as cancer antigen delivery vehicles for macrophage based antitumor vaccine.

    Science.gov (United States)

    Chattopadhyay, Sourav; Dash, Sandeep Kumar; Mandal, Debasis; Das, Balaram; Tripathy, Satyajit; Dey, Aditi; Pramanik, Panchanan; Roy, Somenath

    2016-02-10

    In the present study, we would like to evaluate the efficacy of modified metal oxide nanoparticles (NPs) as cancer antigen delivery vehicles for macrophage (MФs) based antitumor vaccine. The cobalt oxide nanoparticles (CoO NPs) were promising tools for delivery of antigens to antigen presenting cells and have induced an antitumor immune response. Synthesized CoO NPs were modified by N-phosphonomethyliminodiacetic acid (PMIDA), facilitated the conjugation of lysate antigen, i.e. cancer antigen derived from lysis of cancer cells. The cancer cell lysate antigen conjugated PMIDA-CoO NPs (Ag-PMIDA-CoO NPs) successfully activated macrophage (MФ) evident by the increasing the serum IFN-γ and TNF-α level. Immunization of mice with the Ag-PMIDA-CoO NPs constructed an efficient immunological adjuvant induced anticancer IgG responses, and increased the antibody dependent cellular cytotoxicity (ADCC) response than only lysate antigen treated group to combat the cancer cell. The nanocomplexes enhanced the anticancer CD4(+)T cell response in mice. The result showed that Ag-PMIDA-CoO NPs can stimulate the immune responses over only lysate antigens, which are the most important findings in this study. These NP-mediated Ag deliveries may significantly improve the anticancer immune response by activating MФs and may act as adjuvant and will balance the pro-inflammatory and anti-inflammatory immunoresponse. The crosstalk between the activated MФ with other immune competent cells will be monitored by measuring the cytokines which illustrate the total immunological network setups.

  10. Tapasin discriminates peptide-human leukocyte antigen-A*02:01 complexes formed with natural ligands

    DEFF Research Database (Denmark)

    Røder, Gustav Andreas; Geironson, Linda; Rasmussen, Michael;

    2011-01-01

    according to the identity of the peptide. The facilitation was also specific for the identity of the HLA-I heavy chain, where it correlated to established tapasin dependence hierarchies. Two large sets of HLA-A*02:01 binding peptides, one extracted from natural HLA-I ligands from the SYFPEITHI database......A plethora of peptides are generated intracellularly, and most peptide-human leukocyte antigen (HLA)-I interactions are of a transient, unproductive nature. Without a quality control mechanism, the HLA-I system would be stressed by futile attempts to present peptides not sufficient for the stable...

  11. Small-angle neutron scattering study of recombinant yeast-derived human hepatitis B virus surface antigen vaccine particle

    Science.gov (United States)

    Sato, M.; Ito, Y.; Kameyama, K.; Imai, M.; Ishikawa, N.; Takagi, T.

    1995-02-01

    The overall and internal structure of recombinant yeast-derived human hepatitis B virus surface antigen vaccine particles was investigated by small-angle neutron scattering using the contrast variation method. The vaccine is a nearly spherical particle, and its contrast-matching point was determined to be at about 24% D 2O content, indicating that a large part of the vaccine particle is occupied by lipids and carbohydrates from the yeast. The Stuhrmann plot suggests that the surface antigens exist predominantly in the peripheral region of the particle, which is favorable to the induction of anti-virus antibodies.

  12. Association of WT1 IgG antibody against WT1 peptide with prolonged survival in glioblastoma multiforme patients vaccinated with WT1 peptide.

    Science.gov (United States)

    Oji, Yusuke; Hashimoto, Naoya; Tsuboi, Akihiro; Murakami, Yui; Iwai, Miki; Kagawa, Naoki; Chiba, Yasuyoshi; Izumoto, Shuichi; Elisseeva, Olga; Ichinohasama, Ryo; Sakamoto, Junichi; Morita, Satoshi; Nakajima, Hiroko; Takashima, Satoshi; Nakae, Yoshiki; Nakata, Jun; Kawakami, Manabu; Nishida, Sumiyuki; Hosen, Naoki; Fujiki, Fumihiro; Morimoto, Soyoko; Adachi, Mayuko; Iwamoto, Masahiro; Oka, Yoshihiro; Yoshimine, Toshiki; Sugiyama, Haruo

    2016-09-15

    We previously evaluated Wilms' tumor gene 1 (WT1) peptide vaccination in a large number of patients with leukemia or solid tumors and have reported that HLA-A*24:02 restricted, 9-mer WT1-235 peptide (CYTWNQMNL) vaccine induces cellular immune responses and elicits WT1-235-specific cytotoxic T lymphocytes (CTLs). However, whether this vaccine induces humoral immune responses to produce WT1 antibody remains unknown. Thus, we measured IgG antibody levels against the WT1-235 peptide (WT1-235 IgG antibody) in patients with glioblastoma multiforme (GBM) receiving the WT1 peptide vaccine. The WT1-235 IgG antibody, which was undetectable before vaccination, became detectable in 30 (50.8%) of a total of 59 patients during 3 months of WT1 peptide vaccination. The dominant WT1-235 IgG antibody subclass was Th1-type, IgG1 and IgG3 . WT1-235 IgG antibody production was significantly and positively correlated with both progression-free survival (PFS) and overall survival (OS). Importantly, the combination of WT1-235 IgG antibody production and positive delayed type-hypersensitivity (DTH) to the WT1-235 peptide was a better prognostic marker for long-term OS than either parameter alone. These results suggested that WT1-235 peptide vaccination induces not only WT1-235-specific CTLs as previously described but also WT1-235-specific humoral immune responses associated with antitumor cellular immune response. Our results indicate that the WT1 IgG antibody against the WT1 peptide may be a useful predictive marker, with better predictive performance in combination with DTH to WT1 peptide, and provide a new insight into the antitumor immune response induction in WT1 peptide vaccine-treated patients. PMID:27170523

  13. A Brief Review of Computer-Assisted Approaches to Rational Design of Peptide Vaccines

    Directory of Open Access Journals (Sweden)

    Ashesh Nandy

    2016-05-01

    Full Text Available The growing incidences of new viral diseases and increasingly frequent viral epidemics have strained therapeutic and preventive measures; the high mutability of viral genes puts additional strains on developmental efforts. Given the high cost and time requirements for new drugs development, vaccines remain as a viable alternative, but there too traditional techniques of live-attenuated or inactivated vaccines have the danger of allergenic reactions and others. Peptide vaccines have, over the last several years, begun to be looked on as more appropriate alternatives, which are economically affordable, require less time for development and hold the promise of multi-valent dosages. The developments in bioinformatics, proteomics, immunogenomics, structural biology and other sciences have spurred the growth of vaccinomics where computer assisted approaches serve to identify suitable peptide targets for eventual development of vaccines. In this mini-review we give a brief overview of some of the recent trends in computer assisted vaccine development with emphasis on the primary selection procedures of probable peptide candidates for vaccine development.

  14. A Brief Review of Computer-Assisted Approaches to Rational Design of Peptide Vaccines

    Science.gov (United States)

    Nandy, Ashesh; Basak, Subhash C.

    2016-01-01

    The growing incidences of new viral diseases and increasingly frequent viral epidemics have strained therapeutic and preventive measures; the high mutability of viral genes puts additional strains on developmental efforts. Given the high cost and time requirements for new drugs development, vaccines remain as a viable alternative, but there too traditional techniques of live-attenuated or inactivated vaccines have the danger of allergenic reactions and others. Peptide vaccines have, over the last several years, begun to be looked on as more appropriate alternatives, which are economically affordable, require less time for development and hold the promise of multi-valent dosages. The developments in bioinformatics, proteomics, immunogenomics, structural biology and other sciences have spurred the growth of vaccinomics where computer assisted approaches serve to identify suitable peptide targets for eventual development of vaccines. In this mini-review we give a brief overview of some of the recent trends in computer assisted vaccine development with emphasis on the primary selection procedures of probable peptide candidates for vaccine development. PMID:27153063

  15. A Brief Review of Computer-Assisted Approaches to Rational Design of Peptide Vaccines.

    Science.gov (United States)

    Nandy, Ashesh; Basak, Subhash C

    2016-05-04

    The growing incidences of new viral diseases and increasingly frequent viral epidemics have strained therapeutic and preventive measures; the high mutability of viral genes puts additional strains on developmental efforts. Given the high cost and time requirements for new drugs development, vaccines remain as a viable alternative, but there too traditional techniques of live-attenuated or inactivated vaccines have the danger of allergenic reactions and others. Peptide vaccines have, over the last several years, begun to be looked on as more appropriate alternatives, which are economically affordable, require less time for development and hold the promise of multi-valent dosages. The developments in bioinformatics, proteomics, immunogenomics, structural biology and other sciences have spurred the growth of vaccinomics where computer assisted approaches serve to identify suitable peptide targets for eventual development of vaccines. In this mini-review we give a brief overview of some of the recent trends in computer assisted vaccine development with emphasis on the primary selection procedures of probable peptide candidates for vaccine development.

  16. Identifying protective Streptococcus pyogenes vaccine antigens recognized by both B and T cells in human adults and children

    DEFF Research Database (Denmark)

    Mortensen, Rasmus; Nissen, Thomas Nørrelykke; Fredslund, Sine;

    2016-01-01

    No commercial vaccine exists against Group A streptococci (GAS; Streptococcus pyogenes) and only little is known about anti-GAS protective immunity. In our effort to discover new protective vaccine candidates, we selected 21 antigens based on an in silico evaluation. These were all well......-conserved among different GAS strains, upregulated in host-pathogen interaction studies, and predicted to be extracellular or associated with the surface of the bacteria. The antigens were tested for both antibody recognition and T cell responses in human adults and children. The antigenicity of a selected group...

  17. Enhanced protective efficacy of a chimeric form of the schistosomiasis vaccine antigen Sm-TSP-2.

    Directory of Open Access Journals (Sweden)

    Mark S Pearson

    Full Text Available The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG(1 and IgG(3 from putatively resistant individuals resident in S. mansoni endemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to the immunogenic 5B region of the hookworm aspartic protease and vaccine antigen, Na-APR-1. Sm-TSP-2 formulated with alum/CpG showed significant reductions in adult worm and liver egg burdens in two separate murine schistosomiasis challenge studies. Sm-TSP-2/5B afforded significantly greater protection than Sm-TSP-2 alone when both antigens were formulated with alum/CpG. The enhanced protection obtained with the chimeric fusion protein was associated with increased production of anti-Sm-TSP-2 antibodies and IL-4, IL-10 and IFN-γ from spleen cells of vaccinated animals. Sera from 666 individuals from Brazil who were infected with S. mansoni were screened for potentially deleterious IgE responses to Sm-TSP-2. Anti-Sm-TSP-2 IgE to this protein was not detected (also shown previously for Na-APR-1, suggesting that the chimeric antigen Sm-TSP-2/5B could be used to safely and effectively vaccinate people in areas where schistosomes and hookworms are endemic.

  18. Review of hepatitis B surface antigen-1018 ISS adjuvant-containing vaccine safety and efficacy.

    Science.gov (United States)

    Barry, Mazin; Cooper, Curtis

    2007-11-01

    Existing hepatitis B virus (HBV) vaccines produce seroprotective titers in > 90% of healthy adult recipients following 3 doses administered over 6 months. The durability of this response is variable. Vaccine efficacy is greatly diminished in immune compromised patients. Given the high worldwide prevalence and burden of disease produced by chronic HBV infection, vaccines capable of producing high rates of durable seroprotective HBV surface antibody titers are required. Immunostimulatory sequences (ISS) containing repeating sequences of cytosine phosphoguanosine (CpG) dinucleotide motifs have emerged as useful tools for modulating immune responses. Dynavax Technologies produced a synthetic oligodexynucleotide (ODN) containing these motifs, resulting in an unmethylated cytosine and phosphoguanosine ODN called 1018 ISS. Dynavax's hepatitis B virus vaccine HEPLISAV is comprised of 1018 ISS mixed with recombinant hepatitis B surface antigen. Clinical trials, to date, have shown that HEPLISAV produces rapid, high titer, sustained seroprotection in healthy adults and vaccine hyporesponsive populations. Although additional supporting data are required, this represents a promising strategy to facilitate worldwide HBV prevention efforts. PMID:17961095

  19. A modern approach for epitope prediction: identification of foot-and-mouth disease virus peptides binding bovine leukocyte antigen (BoLA) class I molecules

    Science.gov (United States)

    Major histocompatibility complex (MHC) class I molecules regulate adaptive immune responses through the presentation of antigenic peptides to CD8positive T-cells. Polymorphisms in the peptide binding region of class I molecules determine peptide binding affinity and stability during antigen presenta...

  20. Linkage of bacterial protein synthesis and presentation of MHC class I-restricted Listeria monocytogenes-derived antigenic peptides.

    Directory of Open Access Journals (Sweden)

    Silke Grauling-Halama

    Full Text Available The processing and MHC class I-restricted presentation of antigenic peptides derived from the p60 protein of the facultative intracellular bacterium Listeria monocytogenes is tightly linked to bacterial protein synthesis. We used non-linear regression analysis to fit a mathematical model of bacterial antigen processing to a published experimental data set showing the accumulation and decay of p60-derived antigenic peptides in L. monocytogenes-infected cells. Two alternative models equally describe the experimental data. The simulation accounting for a stable and a hypothetical rapidly degraded form of antigen predicts that the antigenic peptides p60 217-225 and p60 449-457 are derived from a putative instable form of p60 with an average intracellular half-life of approximately 3 minutes accounting for approximately 31% of all p60 molecules synthesized. The alternative model predicts that both antigenic peptides are processed from p60 degraded intracellularly with a half-life of 109 min and that antigen processing only occurs as long as bacterial protein synthesis is not inhibited. In order to decide between both models the intracellular accumulation of p60 in infected cells was studied experimentally and compared with model predictions. Inhibition of p60 degradation by the proteasome inhibitor epoxomicin revealed that during the first 3 h post infection approximately 30% of synthesized p60 molecules were degraded. This value is significantly lower than the approximately 50% degradation of p60 that would be expected in the presence of the predicted putative short-lived state of p60 and also fits precisely with the predictions of the alternative model, indicating that the tight connection of bacterial protein biosynthesis and antigen processing and presentation of L. monocyctogenes-derived antigenic peptides is not caused by the presence of a highly instable antigenic substrate.

  1. Synthetic Peptide Ligands of the Antigen Binding Receptor Induce Programmed Cell Death in a Human B-Cell Lymphoma

    Science.gov (United States)

    Renschler, Markus F.; Bhatt, Ramesh R.; Dower, William J.; Levy, Ronald

    1994-04-01

    Peptide ligands for the antigen binding site of the surface immunoglobulin receptor of a human B-cell lymphoma cell line were identified with the use of filamentous phage libraries displaying random 8- and 12-amino acid peptides. Corresponding synthetic peptides bound specifically to the antigen binding site of this immunoglobulin receptor and blocked the binding of an anti-idiotype antibody. The ligands, when conjugated to form dimers or tetramers, induced cell death by apoptosis in vitro with an IC50 between 40 and 200 nM. This effect was associated with specific stimulation of intracellular protein tyrosine phosphorylation.

  2. Antigen-oriented T cell migration contributes to myelin peptide induced-EAE and immune tolerance.

    Science.gov (United States)

    Zheng, Peiguo; Fu, Hanxiao; Wei, Gaohui; Wei, Zhongwei; Zhang, Junhua; Ma, Xuehan; Rui, Dong; Meng, Xianchun; Ming, Liang

    2016-08-01

    Treatment with soluble myelin peptide can efficiently and specifically induce tolerance to demyelination autoimmune diseases including multiple sclerosis, however the mechanism underlying this therapeutic effect remains to be elucidated. In actively induced mouse model of experimental autoimmune encephalomyelitis (EAE) we analyzed T cell and innate immune cell responses in the central nervous system (CNS) and spleen after intraperitoneal (i.p.) infusion of myelin oligodendrocyte glycoprotein (MOG). We found that i.p. MOG infusion blocked effector T cell recruitment to the CNS and protected mice from EAE and lymphoid organ atrophy. Innate immune CD11b(+) cells preferentially recruited MOG-specific effector T cells, particularly when activated to become competent antigen presenting cells (APCs). During EAE development, mature APCs were enriched in the CNS rather than in the spleen, attracting effector T cells to the CNS. Increased myelin antigen exposure induced CNS-APC maturation, recruiting additional effector T cells to the CNS, causing symptoms of disease. MOG triggered functional maturation of splenic APCs. MOG presenting APCs interacted with MOG-specific T cells in the spleen, aggregating to cluster around CD11b(+) cells, and were trapped in the periphery. This process was MHC II dependent as an MHC II directed antibody blocked CD4(+) T cell cluster formation. These findings highlight the role of myelin peptide-loaded APCs in myelin peptide-induced EAE and immune tolerance. PMID:27327113

  3. Evaluation of three recombinant multi-antigenic vaccines composed of surface and secretory antigens of Toxoplasma gondii in murine models of experimental toxoplasmosis.

    Science.gov (United States)

    Dziadek, Bozena; Gatkowska, Justyna; Brzostek, Anna; Dziadek, Jaroslaw; Dzitko, Katarzyna; Grzybowski, Marcin; Dlugonska, Henryka

    2011-01-17

    The great clinical and economical impact of Toxoplasma gondii infections makes the development of an effective vaccine for controlling toxoplasmosis an extremely important aim. In the presented study, we evaluate the protective and immunogenic properties of three recombinant subunit vaccines composed of rROP2+rGRA4+rSAG1, rROP2+rROP4+rGRA4 and rROP2+rROP4+rSAG1 proteins of T. gondii in an experimental toxoplasmosis model in the C3H/HeJ and C57BL/6 mouse strains. All three recombinant vaccines induced partial protection as measured by the reduction of brain cyst burden following challenge with five tissue cysts of the low virulence DX T. gondii strain. The level of protection was dependent on the antigen composition of the vaccine and the genetic background of the laboratory animals. The strongest protection against chronic toxoplasmosis was induced in both C3H/HeJ and C57BL/6 mice by the mixture of rhoptry proteins rROP2 and rROP4 combined with tachyzoite major protein rSAG1. The average parasite burden in these groups of mice was reduced by 71% and 90%, respectively, compared to non-vaccinated mice. The observed protective effect was related to the vaccine-induced cellular and humoral immune responses, as measured by the antigen-induced release of the Th1 cytokines IFN-γ and IL-2, the antigen-stimulated proliferation of spleen cells of vaccinated animals in comparison to control animals and the development of systemic antigen-specific IgG1 and IgG2a (C3H/HeJ) or IgG2c (C57BL/6) antibodies. Our studies show that recombinant rROP2, rROP4, rGRA4 and rSAG1 antigens may be promising candidates for a subunit vaccine against toxoplasmosis. Additionally, we demonstrate that the ideal composition of vaccine antigens can be equally effective in mice with different genetic backgrounds and variable levels of innate resistance to toxoplasmosis, resulting in strong protection against T. gondii invasion.

  4. Identification of an OmpW homologue in Burkholderia pseudomallei, a protective vaccine antigen against melioidosis.

    Science.gov (United States)

    Casey, William T; Spink, Natasha; Cia, Felipe; Collins, Cassandra; Romano, Maria; Berisio, Rita; Bancroft, Gregory J; McClean, Siobhán

    2016-05-17

    Burkholderia pseudomallei is the causative agent of melioidosis, which is associated with a range of clinical manifestations, including sepsis and fatal pneumonia and is endemic in Southeast Asia and Northern Australia. Treatment can be challenging and control of infection involves prolonged antibiotic therapy, yet there are no approved vaccines available to prevent infection. Our aim was to develop and assess the potential of a prophylactic vaccine candidate targeted against melioidosis. The identified candidate is the 22kDa outer membrane protein, OmpW. We previously demonstrated that this protein was immunoprotective in mouse models of Burkholderia cepacia complex (Bcc) infections. We cloned Bp_ompW in Escherichia coli, expressed and purified the protein. Endotoxin free protein administered with SAS adjuvant protected Balb/C mice (75% survival) relative to controls (25% survival) (p<0.05). A potent serological response was observed with IgG2a to IgG1 ratio of 6.0. Furthermore C57BL/6 mice were protected for up to 80 days against a lethal dose of B. pseudomallei and surpassed the efficacy of the live attenuated 2D2 positive control. BpompW is homologous across thirteen sequenced B. pseudomallei strains, indicating that it should be broadly protective against B. pseudomallei. In conclusion, we have demonstrated that BpOmpW is able to induce protective immunity against melioidosis and is likely to be an effective vaccine antigen, possibly in combination with other subunit antigens. PMID:27091689

  5. Vaccine potential of plasma bead-based dual antigen delivery system against experimental murine candidiasis.

    Science.gov (United States)

    Ahmad, Ejaj; Zia, Qamar; Fatima, Munazza Tamkeen; Owais, Mohammad; Saleemuddin, Mohammed

    2015-11-01

    The development of prophylactic anti-candidal vaccine comprising the Candida albicans cytosolic proteins (Cp) as antigen and plasma beads (PB) prepared from plasma as sustained delivery system, is described. The immune-prophylactic potential of various PBs-based dual antigen delivery systems, co-entrapping Cp pre-entrapped in PLGA microspheres were tested in the murine model. Induction of cell mediated immunity was measured by assaying DTH and NO production as well as in vitro proliferation of lymphocytes derived from the immunized animals. Expression of surface markers on APCs (CD80, CD86) and T-cells (CD4+, CD8+) was also evaluated. Humoral immune response was studied by measuring circulating anti-Cp antibodies and their subclasses. When the prophylactic efficacy of the vaccines was tested in mice challenged with virulent C. albicans, the PB-based formulation (PB-PLGA-Cp vaccine) was found to be most effective in the generation of desirable immune response, in terms of suppression of fungal load and facilitating the survival of the immunized animals.

  6. Investigation of the response to the enterobacterial common antigen after typhoid vaccination

    Directory of Open Access Journals (Sweden)

    Arlete M. Milhomem

    1987-03-01

    Full Text Available Antibodies against the Salmonella typhi enterobacterial common antigen (ECA and the O and H antigens were investigated in sera from healthy male subjects who had been previously vaccinated with the typhoid vaccine. No serological response to ECA was observed. Sera from subjects not previously vaccinated presented titers of ECA hemagglutinins which quantitatively were related to the presence ofH titers, but not to O agglutinins but with no statistical significance. The results are discussed in relation to the possible protective immunological mechanisms in typhoid fever.Anticorpos contra o antígeno comum de enterobactérias (ECA bem como contra os antigenos somáticos (O e flagelar (H de Salmonella typhi foram investigados no soro de recrutas do sexo masculino, após a vacinação. Não fo i detectada resposta humoral para ECA. Os soros obtidos antes da vacinação mostraram hemaglutininas para ECA acompanhando a presença de aglutininas para o antígeno H, ao contrário do que se observou em relação ao antígeno O. Discutem-se os resultados quanto ao possível mecanismo da imunoproteção da febre tifóide.

  7. Nanogel antigenic protein-delivery system for adjuvant-free intranasal vaccines.

    Science.gov (United States)

    Nochi, Tomonori; Yuki, Yoshikazu; Takahashi, Haruko; Sawada, Shin-ichi; Mejima, Mio; Kohda, Tomoko; Harada, Norihiro; Kong, Il Gyu; Sato, Ayuko; Kataoka, Nobuhiro; Tokuhara, Daisuke; Kurokawa, Shiho; Takahashi, Yuko; Tsukada, Hideo; Kozaki, Shunji; Akiyoshi, Kazunari; Kiyono, Hiroshi

    2010-07-01

    Nanotechnology is an innovative method of freely controlling nanometre-sized materials. Recent outbreaks of mucosal infectious diseases have increased the demands for development of mucosal vaccines because they induce both systemic and mucosal antigen-specific immune responses. Here we developed an intranasal vaccine-delivery system with a nanometre-sized hydrogel ('nanogel') consisting of a cationic type of cholesteryl-group-bearing pullulan (cCHP). A non-toxic subunit fragment of Clostridium botulinum type-A neurotoxin BoHc/A administered intranasally with cCHP nanogel (cCHP-BoHc/A) continuously adhered to the nasal epithelium and was effectively taken up by mucosal dendritic cells after its release from the cCHP nanogel. Vigorous botulinum-neurotoxin-A-neutralizing serum IgG and secretory IgA antibody responses were induced without co-administration of mucosal adjuvant. Importantly, intranasally administered cCHP-BoHc/A did not accumulate in the olfactory bulbs or brain. Moreover, intranasally immunized tetanus toxoid with cCHP nanogel induced strong tetanus-toxoid-specific systemic and mucosal immune responses. These results indicate that cCHP nanogel can be used as a universal protein-based antigen-delivery vehicle for adjuvant-free intranasal vaccination. PMID:20562880

  8. Biological role of surface Toxoplasma gondii antigen in development of vaccine

    Institute of Scientific and Technical Information of China (English)

    Ke-Yi Liu; Dian-Bo Zhang; Qing-Kuan Wei; Jin Li; Gui-Ping Li; Jin-Zhi Yu

    2006-01-01

    AIM: To analyze the biological role of the surface antigen of Toxoplasma gondii (T gondii) in development of vaccine.METHODS: The surface antigen of Tgondii (SAG1)was expressed in vitro. The immune response of the host to the antigen was investigated by detection of specific antibody reaction to SAG1 and production of cytokines. Mice were immunized with recombinant SAG1and challenged with lethal strain of T gondii RH. The monoclonal antibody to r-SAG1 was prepared and used to study the effects of SAG1 on T gondii tachyzoites under electromicroscope.RESULTS:The mice immunized with recombinant SAG1 delayed death for 60 h compared to the control group.The recombinant SAG1 induced specific high titer of IgG and IgM antibodies as well as IFN-γ, IL-2 and IL-4cytokines in mice. In contrast, IL-12, IL-6 and TNF-αwere undetectable. When T gondii tachyzoites were treated with the monoclonal antibody to r-SAG1, the parasites were gathered together, destroyed, deformed,swollen, and holes and gaps formed on the surface.CONCLUSION: SAG1 may be an excellent vaccine candidate against T gondii. The immune protection induced by SAG1 against Tgondii may be regulated by both hormone- and cell-mediated immune response.

  9. Neisseria meningitidis antigen NMB0088: sequence variability, protein topology and vaccine potential.

    Science.gov (United States)

    Sardiñas, Gretel; Yero, Daniel; Climent, Yanet; Caballero, Evelin; Cobas, Karem; Niebla, Olivia

    2009-02-01

    The significance of Neisseria meningitidis serogroup B membrane proteins as vaccine candidates is continually growing. Here, we studied different aspects of antigen NMB0088, a protein that is abundant in outer-membrane vesicle preparations and is thought to be a surface protein. The gene encoding protein NMB0088 was sequenced in a panel of 34 different meningococcal strains with clinical and epidemiological relevance. After this analysis, four variants of NMB0088 were identified; the variability was confined to three specific segments, designated VR1, VR2 and VR3. Secondary structure predictions, refined with alignment analysis and homology modelling using FadL of Escherichia coli, revealed that almost all the variable regions were located in extracellular loop domains. In addition, the NMB0088 antigen was expressed in E. coli and a procedure for obtaining purified recombinant NMB0088 is described. The humoral immune response elicited in BALB/c mice was measured by ELISA and Western blotting, while the functional activity of these antibodies was determined in a serum bactericidal assay and an animal protection model. After immunization in mice, the recombinant protein was capable of inducing a protective response when it was administered inserted into liposomes. According to our results, the recombinant NMB0088 protein may represent a novel antigen for a vaccine against meningococcal disease. However, results from the variability study should be considered for designing a cross-protective formulation in future studies.

  10. A plant-produced protective antigen vaccine confers protection in rabbits against a lethal aerosolized challenge with Bacillus anthracis Ames spores

    OpenAIRE

    Chichester, Jessica A.; Manceva, Slobodanka D; Rhee, Amy; Coffin, Megan V.; Musiychuk, Konstantin; Mett, Vadim; Shamloul, Moneim; Norikane, Joey; Streatfield, Stephen J.; Yusibov, Vidadi

    2013-01-01

    The potential use of Bacillus anthracis as a bioterrorism weapon threatens the security of populations globally, requiring the immediate availability of safe, efficient and easily delivered anthrax vaccine for mass vaccination. Extensive research efforts have been directed toward the development of recombinant subunit vaccines based on protective antigen (PA), the principal virulence factor of B. anthracis. Among the emerging technologies for the production of these vaccine antigens is our la...

  11. Conservation analysis of dengue virust-cell epitope-based vaccine candidates using peptide block entropy

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn; Zhang, Guang Lan; Keskin, Derin B.;

    2011-01-01

    Broad coverage of the pathogen population is particularly important when designing CD8+ T-cell epitope vaccines against viral pathogens. Traditional approaches are based on combinations of highly conserved T-cell epitopes. Peptide block entropy analysis is a novel approach for assembling sets....... In contrast, the benchmark study by Khan et al. (2008) resulted in 165 conserved 9-mer peptides. Many of the conserved blocks are located consecutively in the proteins. Connecting these blocks resulted in 78 conserved regions. Of the 1551 blocks of 9-mer peptides 110 comprised predicted HLA binder sets...

  12. HA03 as an Iranian Candidate Concealed Antigen for Vaccination against Hyalomma anatolicum anatolicum: Comparative Structural and In silico Studies

    Directory of Open Access Journals (Sweden)

    Mohammadi, A.

    2013-12-01

    Full Text Available In the last decades researchers had focused on developing a vaccine against tick based on protective antigen. Recombinant vaccines based on concealed antigen from Boophilus microplus have been developed in Australia and Cuba by the name of TICKGARD and GAVAC (De La Fuente and Kocan, 2006. Further studies on this antigen have shown some extent of protection against other species (De Vos et al., 2001. In Iran most important species is Hyalomma anatolicum and limited information about its control are available. This paper reports structural and polymorphic analysis of HA03 as an Iranian candidate concealed antigen of H. a. anatolicum deposited in Gen-Bank .(Aghaeipour et al. GQ228820. The comparison between this antigen and other mid gut concealed antigen that their characteristics are available in GenBank showed there are high rate of similarity between them. The HA03 amino acid sequence had a homology of around 89%, 64%, 56% with HA98, BM86, BM95 respectively. Potential of MHC class I and II binding region indicated a considerable variation between BM86 antigen and its efficiency against Iranian H. a. anatolicum. In addition, predicted major of hydrophobisity and similarity in N-glycosylation besides large amount of cystein and seven EGF like regions presented in protein structure revealed that value of HA03 as a new protective antigen and the necessity of the development, BM86 homolog of H. a. anatolicum HA03 based recombinant vaccine.

  13. Sequence Variation and Immunologic Cross-Reactivity among Babesia bovis Merozoite Surface Antigen 1 Proteins from Vaccine Strains and Vaccine Breakthrough Isolates

    Science.gov (United States)

    LeRoith, Tanya; Brayton, Kelly A.; Molloy, John B.; Bock, Russell E.; Hines, Stephen A.; Lew, Ala E.; McElwain, Terry F.

    2005-01-01

    The Babesia bovis merozoite surface antigen 1 (MSA-1) is an immunodominant membrane glycoprotein that is the target of invasion-blocking antibodies. While antigenic variation has been demonstrated in MSA-1 among strains from distinct geographical areas, the extent of sequence variation within a region where it is endemic and the effect of variation on immunologic cross-reactivity have not been assessed. In this study, sequencing of MSA-1 from two Australian B. bovis vaccine strains and 14 breakthrough isolates from vaccinated animals demonstrated low sequence identity in the extracellular region of the molecule, ranging from 19.8 to 46.7% between the T vaccine strain and eight T vaccine breakthrough isolates, and from 18.7 to 99% between the K vaccine strain and six K vaccine breakthrough isolates. Although MSA-1 amino acid sequence varied substantially among strains, overall predicted regions of hydrophilicity and hydrophobicity in the extracellular domain were conserved in all strains examined, suggesting a conserved functional role for MSA-1 despite sequence polymorphism. Importantly, the antigenic variation created by sequence differences resulted in a lack of immunologic cross-reactivity among outbreak strains using sera from animals infected with the B. bovis vaccine strains. Additionally, sera from cattle hyperinfected with the Mexico strain of B. bovis and shown to be clinically immune did not cross-react with MSA-1 from any other isolate tested. The results indicate that isolates of B. bovis capable of evading vaccine-induced immunity contain an msa-1 gene that is significantly different from the msa-1 of the vaccine strain, and that the difference can result in a complete lack of cross-reactivity between MSA-1 from vaccine and breakthrough strains in immunized animals. PMID:16113254

  14. Probing the S1 specificity pocket of the aminopeptidases that generate antigenic peptides: S1 specificity of ERAP1, ERAP2 and IRAP

    OpenAIRE

    Zervoudi, Efthalia; Papakyriakou, Athanasios; Georgiadou, Dimitra; Evnouchidou, Irini; Gajda, Anna; Poreba, Marcin; Salvesen, Guy S.; Drag, Marcin; Hattori, Akira; Swevers, Luc; Vourloumis, Dionisios; Stratikos, Efstratios

    2011-01-01

    ER aminopeptidase 1 (ERAP1), ER aminopeptidase 2 (ERAP2) and Insulin Regulated aminopeptidase (IRAP) are three homologous enzymes that play critical roles in the generation of antigenic peptides. These aminopeptidases excise amino acids from N-terminally extended precursors of antigenic peptides in order to generate the correct length epitopes for binding onto MHC class I molecules. The specificity of these peptidases can affect antigenic peptide selection, but has not yet been investigated i...

  15. Mapping the antigenic structure of porcine parvovirus at the level of peptides

    DEFF Research Database (Denmark)

    Kamstrup, Søren; Langeveld, Jan; Bøtner, Anette;

    1998-01-01

    located in the region corresponding to the major capsid protein VP2. Based on this information, and on analogy to other autonomous parvoviruses, 24 different peptides were synthesised, coupled to keyhole limpet haemocyanin (KLH) and used to immunise rabbits. Most antisera were able to bind viral protein......The antigenic structure of the capsid proteins of porcine parvovirus (PPV) was investigated. A total of nine linear epitopes were identified by Pepscan using porcine or rabbit anti-PPV antisera. No sites were identified with a panel of neutralising monoclonal antibodies (MAbs). All epitopes were...

  16. Characterization of antigen processing and presentation by peptide-linked MHC class I molecules

    OpenAIRE

    Tiwari, Neeraj

    2005-01-01

    MHC-Klasse-I-Moleküle präsentieren gewöhnlich Peptide, die aus zytosolischen Antigenproteinen durch proteasomalen Verdau generiert und anschließend vom TAP-Peptidtransporter ins endoplasmatische Retikulum transportiert werden. Es können jedoch auch endozytierte Antigene für die MHC-Klasse-I-vermittelten Antigenpräsentation prozessiert werden, wobei dieser alternative Weg entweder in einer Proteasom/TAP-abhängigen oder unabhängigen Weise abläuft. Während diese so genannte „Kreuzpräsentation“ f...

  17. Non-immunogenicity of overlapping gag peptides pulsed on autologous cells after vaccination of HIV infected individuals.

    Directory of Open Access Journals (Sweden)

    Henrik N Kløverpris

    Full Text Available BACKGROUND: HIV Gag-specific CD4+ and CD8+ T-cell responses are important for HIV immune control. Pulsing overlapping Gag peptides on autologous lymphocytes (OPAL has proven immunogenic and effective in reducing viral loads in multiple pigtail macaque studies, warranting clinical evaluation. METHODOLOGY: We performed a phase I, single centre, placebo-controlled, double-blinded and dose-escalating study to evaluate the safety and preliminary immunogenicity of a novel therapeutic vaccine approach 'OPAL-HIV-Gag(c'. This vaccine is comprised of 120 15mer peptides, overlapping by 11 amino acids, spanning the HIV Gag C clade sequence proteome, pulsed on white blood cells enriched from whole blood using a closed system, followed by intravenous reinfusion. Patients with undetectable HIV viral loads (<50 copies/ml plasma on HAART received four administrations at week 0, 4, 8 and 12, and were followed up for 12 weeks post-treatment. Twenty-three people were enrolled in four groups: 12 mg (n = 6, 24 mg (n = 7, 48 mg (n = 2 or matching placebo (n = 8 with 18 immunologically evaluable. T-cell immunogenicity was assessed by IFNγ ELIspot and intracellular cytokine staining (ICS. RESULTS: The OPAL-HIV-Gag(c peptides were antigenic in vitro in 17/17 subjects. After vaccination with OPAL-HIV-Gag(c, 1/6 subjects at 12 mg and 1/6 subjects at 24 mg dose groups had a 2- and 3-fold increase in ELIspot magnitudes from baseline, respectively, of Gag-specific CD8+ T-cells at week 14, compared to 0/6 subjects in the placebo group. No Gag-specific CD4+ T-cell responses or overall change in Rev, Nef, Tat and CMV specific responses were detected. Marked, transient and self-limiting lymphopenia was observed immediately post-vaccination (4 hours in OPAL-HIV-Gag(c but not in placebo recipients, with median fall from 1.72 to 0.67 million lymphocytes/mL for active groups (P<0.001, compared to post-placebo from 1.70 to 1.56 lymphocytes/ml (P = 0.16. CONCLUSION

  18. Antigen selection for future anti-Trichuris vaccines: a comparison of cytokine and antibody responses to larval and adult antigen in a primary infection.

    Science.gov (United States)

    Dixon, H; Johnston, C E; Else, K J

    2008-09-01

    Trichuriasis, caused by the whipworm Trichuris trichiura, is endemic in tropical and subtropical areas, affecting approximately 1 billion people. Child anthelminthic treatment programmes are being implemented but repeated treatments are costly, may prevent the development of acquired immunity and can lead to the development of drug resistant parasites. Thus, the development of a vaccine which would lead to the acquisition of immunity at an earlier age and reduce community faecal egg output would be beneficial. Development of subunit vaccines requires the identification of protective antigens and their formulation in a suitable adjuvant. Trichuris muris is an antigenically similar laboratory model for T. trichiura. Subcutaneous vaccination with adult excretory-secretory products (ES) protects susceptible mouse strains from T. muris. Larval stages may contain novel and more relevant antigens which when incorporated in a vaccine induce worm expulsion earlier in infection than the adult worm products. This study finds negligible difference in the cellular and humoral immune response to T. muris adult and third stage larva(e) (L3) ES during a primary T. muris infection, but identifies high molecular weight proteins in both adult and L3 ES as potential vaccine candidates.

  19. Identification and evaluation of vaccine candidate antigens from the poultry red mite (Dermanyssus gallinae).

    Science.gov (United States)

    Bartley, Kathryn; Wright, Harry W; Huntley, John F; Manson, Erin D T; Inglis, Neil F; McLean, Kevin; Nath, Mintu; Bartley, Yvonne; Nisbet, Alasdair J

    2015-11-01

    An aqueous extract of the haematophagous poultry ectoparasite, Dermanyssus gallinae, was subfractionated using anion exchange chromatography. Six of these subfractions were used to immunise hens and the blood from these hens was fed, in vitro, to poultry red mites. Mite mortality following these feeds was indicative of protective antigens in two of the subfractions, with the risks of mites dying being 3.1 and 3.7 times higher than in the control group (P<0.001). A combination of two-dimensional immunoblotting and immunoaffinity chromatography, using IgY from hens immunised with these subfractions, was used in concert with proteomic analyses to identify the strongest immunogenic proteins in each of these subfractions. Ten of the immunoreactive proteins were selected for assessment as vaccine candidates using the following criteria: intensity of immune recognition; likelihood of exposure of the antigen to the antibodies in a blood meal; proposed function and known vaccine potential of orthologous molecules. Recombinant versions of each of these 10 proteins were produced in Escherichia coli and were used to immunise hens. Subsequent in vitro feeding of mites on blood from these birds indicated that immunisation with Deg-SRP-1 (serpin), Deg-VIT-1 (vitellogenin), Deg-HGP-1 (hemelipoglycoprotein) or Deg-PUF-1 (a protein of unknown function) resulted in significantly increased risk of mite death (1.7-2.8times higher than in mites fed blood from control hens immunised with adjuvant only, P<0.001). The potential for using these antigens in a recombinant vaccine is discussed.

  20. The role of Plasmodium falciparum variant surface antigens in protective immunity and vaccine development

    DEFF Research Database (Denmark)

    Hviid, Lars

    2010-01-01

    There is substantial immuno-epidemiological evidence that the parasite-encoded, so-called variant surface antigens (VSAs), such as PfEMP1 on the surface of infected erythrocytes (IEs) are important-in some cases probably decisive determinants of clinical outcome of P. falciparum malaria. The...... evidence is increasingly being underpinned by specific molecular understanding of the pathogenic processes involved. Pregnancy-associated malaria (PAM) caused by placenta-sequestering IEs expressing the PfEMP1 variant VAR2CSA is a particularly striking example of this. These findings have raised hopes that...... development of PfEMP1-based vaccines to protect specifically against severe malaria syndromes-in particular PAM-is feasible. This review summarizes the evidence that VSAs are important targets of NAI, discusses why VSA-based vaccines might be feasible despite the extensive intra- and interclonal variation of...

  1. Intranasal Vaccination Affords Localization and Persistence of Antigen-Specific CD8+ T Lymphocytes in the Female Reproductive Tract

    Directory of Open Access Journals (Sweden)

    Shailbala Singh

    2016-03-01

    Full Text Available Immunization strategies generating large numbers of antigen-specific T cells in the female reproductive tract (FRT can provide barrier protection against sexually-transmitted pathogens, such as the human immunodeficiency virus (HIV and human papillomaviruses (HPV. The kinetics and mechanisms of regulation of vaccine-induced adaptive T cell-mediated immune responses in FRT are less well defined. We present here evidence for intranasal delivery of the model antigen ovalbumin (OVA along with alpha-galactosylceramide adjuvant as a protein vaccine to induce significantly higher levels of antigen-specific effector and memory CD8+ T cells in the FRT, relative to other systemic and mucosal tissues. Antibody blocking of the CXCR3 receptor significantly reduced antigen-specific CD8+ T cells subsequent to intranasal delivery of the protein vaccine suggesting an important role for the CXCR3 chemokine-receptor signaling for T cell trafficking. Further, intranasal vaccination with an adenoviral vector expressing OVA or HIV-1 envelope was as effective as intramuscular vaccination for generating OVA- or ENV-specific immunity in the FRT. These results support the application of the needle-free intranasal route as a practical approach to delivering protein as well as DNA/virus vector-based vaccines for efficient induction of effector and memory T cell immunity in the FRT.

  2. A recombinant raccoon poxvirus vaccine expressing both Yersinia pestis F1 and truncated V antigens protects animals against lethal plague.

    Science.gov (United States)

    Rocke, Tonie E.; Kingstad-Bakke, B; Berlier, W; Osorio, J.E.

    2014-01-01

    In previous studies, we demonstrated in mice and prairie dogs that simultaneous administration of two recombinant raccoon poxviruses (rRCN) expressing Yersinia pestis antigens (F1 and V307-a truncated version of the V protein) provided superior protection against plague challenge compared to individual single antigen constructs. To reduce costs of vaccine production and facilitate implementation of a sylvatic plague vaccine (SPV) control program for prairie dogs, a dual antigen construct is more desirable. Here we report the construction and characterization of a novel RCN-vectored vaccine that simultaneously expresses both F1 and V307 antigens. This dual antigen vaccine provided similar levels of protection against plague in both mice and prairie dogs as compared to simultaneous administration of the two single antigen constructs and was also shown to protect mice against an F1 negative strain of Y. pestis.. The equivalent safety, immunogenicity and efficacy profile of the dual RCN-F1/V307 construct warrants further evaluation in field efficacy studies in sylvatic plague endemic areas.

  3. Immunogenicity and safety of hepatitis E vaccine in healthy hepatitis B surface antigen positive adults

    OpenAIRE

    Wu, Ting; Huang, Shou-Jie; Zhu, Feng-Cai; Zhang, Xue-Feng; AI, XING; Yan, Qiang; Wang, Zhong-Ze; Yang, Chang-Lin; Jiang, Han-Min; Liu, Xiao-Hui; Guo, Meng; Du, Hai-Lian; Ng, Mun-Hon; Zhang, Jun; Xia, Ningshao

    2013-01-01

    A recombinant hepatitis E vaccine, Hecolin®, has been proven safe and effective in healthy adults. As hepatitis B surface antigen (HBsAg) positive individuals have a higher risk of poor prognosis after super-infection with hepatitis E virus (HEV), the safety and immunogenicity of Hecolin® in this population should be assessed. The present study is an extending analysis of data from a large randomized controlled clinical trial of Hecolin®. Healthy participants (n = 14,065) without current or p...

  4. Monitoring antigenic variations of enterovirus 71: implications for virus surveillance and vaccine development.

    Directory of Open Access Journals (Sweden)

    Min-Yuan Chia

    2014-07-01

    Full Text Available Enterovirus 71 (EV71 causes life-threatening epidemics in Asia and can be phylogenetically classified into three major genogroups (A ∼ C including 11 genotypes (A, B1 ∼ B5, and C1 ∼ C5. Recently, EV71 epidemics occurred cyclically in Taiwan with different genotypes. In recent years, human studies using post-infection sera obtained from children have detected antigenic variations among different EV71 strains. Therefore, surveillance of enterovirus 71 should include phylogenetic and antigenic analysis. Due to limitation of sera available from children with EV71 primary infection, suitable animal models should be developed to generate a panel of antisera for monitoring EV71 antigenic variations. Twelve reference strains representing the 11 EV71 genotypes were grown in rhabdomyosarcoma cells. Infectious EV71 particles were purified and collected to immunize rabbits. The rabbit antisera were then employed to measure neutralizing antibody titers against the 12 reference strains and 5 recent strains. Rabbits immunized with genogroup B and C viruses consistently have a lower neutralizing antibody titers against genogroup A (≧ 8-fold difference and antigenic variations between genogroup B and C viruses can be detected but did not have a clear pattern, which are consistent with previous human studies. Comparison between human and rabbit neutralizing antibody profiles, the results showed that ≧ 8-fold difference in rabbit cross-reactive antibody ratios could be used to screen EV71 isolates for identifying potential antigenic variants. In conclusion, a rabbit model was developed to monitor antigenic variations of EV71, which are critical to select vaccine strains and predict epidemics.

  5. Tumor Radiation Therapy Creates Therapeutic Vaccine Responses to the Colorectal Cancer Antigen GUCY2C

    International Nuclear Information System (INIS)

    Purpose: Radiation therapy (RT) is thought to produce clinical responses in cancer patients, not only through direct toxicity to cancer cells and supporting tumor stroma cells, but also through activation of immunologic effectors. More recently, RT has potentiated the local and systemic effects of cancer immunotherapy (IT). However, combination regimens that maximize immunologic and clinical efficacy remain undefined. Methods and Materials: We evaluated the impact of local RT on adenoviral-mediated vaccination against the colorectal cancer antigen GUCY2C (Ad5-GUCY2C) in a murine subcutaneous tumor model using mouse CT26 colon cancer cells (CT26-GUCY2C). Immune responses were assessed by ELISpot, and clinical responses were assessed by tumor size and incidence. Results: The specific sequence of tumor-directed RT preceding Ad5-GUCY2C IT transformed inactive therapeutic Ad5-GUCY2C vaccination into a curative vaccine. GUCY2C-specific T cell responses were amplified (P<.05), tumor eradication was maximized (P<.01), and tumor volumes were minimized (P<.001) in mice whose tumors were irradiated before, compared with after, Ad5-GUCY2C vaccination. The immunologic and antitumor efficacy of Ad5-GUCY2C was amplified comparably by unfractionated (8 Gy × 1), or biologically equivalent doses of fractionated (3.5 Gy × 3), RT. The antitumor effects of sequential RT and IT (RT-IT) depended on expression of GUCY2C by tumor cells and the adenoviral vaccine vector, and tumor volumes were inversely related to the magnitude of GUCY2C-specific T cell responses. Moreover, mice cured of CT26-GUCY2C tumors by RT-IT showed long-lasting antigen-dependent protection, resisting tumors formed by GUCY2C-expressing 4T1 breast cancer cells inoculated 50 days after CT26 cells. Conclusions: Optimal sequencing of RT and IT amplifies antigen-specific local and systemic immune responses, revealing novel acute and long-term therapeutic antitumor protection. These observations underscore the importance

  6. Tumor Radiation Therapy Creates Therapeutic Vaccine Responses to the Colorectal Cancer Antigen GUCY2C

    Energy Technology Data Exchange (ETDEWEB)

    Witek, Matthew [Department of Radiation Oncology, Kimmel Cancer Center, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Blomain, Erik S.; Magee, Michael S.; Xiang, Bo; Waldman, Scott A. [Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Snook, Adam E., E-mail: adam.snook@jefferson.edu [Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania (United States)

    2014-04-01

    Purpose: Radiation therapy (RT) is thought to produce clinical responses in cancer patients, not only through direct toxicity to cancer cells and supporting tumor stroma cells, but also through activation of immunologic effectors. More recently, RT has potentiated the local and systemic effects of cancer immunotherapy (IT). However, combination regimens that maximize immunologic and clinical efficacy remain undefined. Methods and Materials: We evaluated the impact of local RT on adenoviral-mediated vaccination against the colorectal cancer antigen GUCY2C (Ad5-GUCY2C) in a murine subcutaneous tumor model using mouse CT26 colon cancer cells (CT26-GUCY2C). Immune responses were assessed by ELISpot, and clinical responses were assessed by tumor size and incidence. Results: The specific sequence of tumor-directed RT preceding Ad5-GUCY2C IT transformed inactive therapeutic Ad5-GUCY2C vaccination into a curative vaccine. GUCY2C-specific T cell responses were amplified (P<.05), tumor eradication was maximized (P<.01), and tumor volumes were minimized (P<.001) in mice whose tumors were irradiated before, compared with after, Ad5-GUCY2C vaccination. The immunologic and antitumor efficacy of Ad5-GUCY2C was amplified comparably by unfractionated (8 Gy × 1), or biologically equivalent doses of fractionated (3.5 Gy × 3), RT. The antitumor effects of sequential RT and IT (RT-IT) depended on expression of GUCY2C by tumor cells and the adenoviral vaccine vector, and tumor volumes were inversely related to the magnitude of GUCY2C-specific T cell responses. Moreover, mice cured of CT26-GUCY2C tumors by RT-IT showed long-lasting antigen-dependent protection, resisting tumors formed by GUCY2C-expressing 4T1 breast cancer cells inoculated 50 days after CT26 cells. Conclusions: Optimal sequencing of RT and IT amplifies antigen-specific local and systemic immune responses, revealing novel acute and long-term therapeutic antitumor protection. These observations underscore the importance

  7. Comparative profile of circulating antigenic peptides in CSF, serum & urine from patients with neurocysticercosis diagnosed by immunoblotting.

    Science.gov (United States)

    Sahu, P S; Parija, S; Kumar, D; Jayachandran, S; Narayan, S

    2014-10-01

    Traditionally serum and/or CSF specimens have been used for detection of either specific antibodies or antigens as a supportive diagnosis of NCC. However, in recent days, much interest has been shown employing noninvasive specimens such as urine. In our study, we identified and compared a profile of circulating antigenic peptides of parasite origin in three different body fluids (CSF, serum and urine) obtained from confirmed NCC cases and control subjects. The circulating antigenic peptides were resolved by SDS-PAGE and subjected to immunoblotting. For confirmation of their origin as parasite somatic or excretory secretory (ES) material, immunoreactivity was tested employing affinity purified polyclonal Taenia solium metacestode anti-somatic or ES antibodies, respectively. Only lower molecular weight antigenic peptides were found circulating in urine in contrast to serum and CSF specimens. Few somatic peptides were identified to be 100% specific for NCC (19·5 kDa in all three specimens; 131, 70 kDa in CSF and serum only; 128 kDa in CSF only). Similarly, the specific ES peptides detected were 32 kDa (in all three specimens), 16·5 kDa (in serum and CSF only), and 15 kDa (urine only). A test format detecting either one or more of these specific peptides would enhance the sensitivity in diagnosis of NCC.

  8. Neutralizing antibody and functional mapping of Bacillus anthracis protective antigen-The first step toward a rationally designed anthrax vaccine.

    Science.gov (United States)

    McComb, Ryan C; Martchenko, Mikhail

    2016-01-01

    Anthrax is defined by the Centers for Disease Control and Prevention as a Category A pathogen for its potential use as a bioweapon. Current prevention treatments include Anthrax Vaccine Adsorbed (AVA). AVA is an undefined formulation of Bacillus anthracis culture supernatant adsorbed to aluminum hydroxide. It has an onerous vaccination schedule, is slow and cumbersome to produce and is slightly reactogenic. Next-generation vaccines are focused on producing recombinant forms of anthrax toxin in a well-defined formulation but these vaccines have been shown to lose potency as they are stored. In addition, studies have shown that a proportion of the antibody response against these vaccines is focused on non-functional, non-neutralizing regions of the anthrax toxin while some essential functional regions are shielded from eliciting an antibody response. Rational vaccinology is a developing field that focuses on designing vaccine antigens based on structural information provided by neutralizing antibody epitope mapping, crystal structure analysis, and functional mapping through amino acid mutations. This information provides an opportunity to design antigens that target only functionally important and conserved regions of a pathogen in order to make a more optimal vaccine product. This review provides an overview of the literature related to functional and neutralizing antibody epitope mapping of the Protective Antigen (PA) component of anthrax toxin. PMID:26611201

  9. Phase I Trial of a CD8+ T-Cell Peptide Epitope-Based Vaccine for Infectious Mononucleosis▿

    OpenAIRE

    Elliott, Suzanne L.; Suhrbier, Andreas; Miles, John J.; Lawrence, Greg; Pye, Stephanie J.; Le, Thuy T.; Rosenstengel, Andrew; Nguyen, Tam; Allworth, Anthony; Burrows, Scott R.; COX, JOHN; Pye, David; Moss, Denis J.; Bharadwaj, Mandvi

    2007-01-01

    A single blind, randomized, placebo-controlled, single-center phase I clinical trial of a CD8+ T-cell peptide epitope vaccine against infectious mononucleosis was conducted with 14 HLA B*0801-positive, Epstein-Barr virus (EBV)-seronegative adults. The vaccine comprised the HLA B*0801-restricted peptide epitope FLRGRAYGL and tetanus toxoid formulated in a water-in-oil adjuvant, Montanide ISA 720. FLRGRAYGL-specific responses were detected in 8/9 peptide-vaccine recipients and 0/4 placebo vacci...

  10. A Novel Virus-Like Particle Based Vaccine Platform Displaying the Placental Malaria Antigen VAR2CSA.

    Directory of Open Access Journals (Sweden)

    Susan Thrane

    Full Text Available Placental malaria caused by Plasmodium falciparum is a major cause of mortality and severe morbidity. Clinical testing of a soluble protein-based vaccine containing the parasite ligand, VAR2CSA, has been initiated. VAR2CSA binds to the human receptor chondroitin sulphate A (CSA and is responsible for sequestration of Plasmodium falciparum infected erythrocytes in the placenta. It is imperative that a vaccine against malaria in pregnancy, if administered to women before they become pregnant, can induce a strong and long lasting immune response. While most soluble protein-based vaccines have failed during clinical testing, virus-like particle (VLP based vaccines (e.g., the licensed human papillomavirus vaccines have demonstrated high efficacy, suggesting that the spatial assembly of the vaccine antigen is a critical parameter for inducing an optimal long-lasting protective immune response. We have developed a VLP vaccine display platform by identifying regions of the HPV16 L1 coat protein where a biotin acceptor site (AviTagTM can be inserted without compromising VLP-assembly. Subsequent biotinylation of Avi-L1 VLPs allow us to anchor monovalent streptavidin (mSA-fused proteins to the biotin, thereby obtaining a dense and repetitive VLP-display of the vaccine antigen. The mSA-VAR2CSA antigen was delivered on the Avi-L1 VLP platform and tested in C57BL/6 mice in comparison to two soluble protein-based vaccines consisting of naked VAR2CSA and mSA-VAR2CSA. The mSA-VAR2CSA Avi-L1 VLP and soluble mSA-VAR2CSA vaccines induced higher antibody titers than the soluble naked VAR2CSA vaccine after three immunizations. The VAR2CSA Avi-L1 VLP vaccine induced statistically significantly higher endpoint titres compared to the soluble mSA-VAR2CSA vaccine, after 1st and 2nd immunization; however, this difference was not statistically significant after 3rd immunization. Importantly, the VLP-VAR2CSA induced antibodies were functional in inhibiting the binding of

  11. The role of peptide and DNA vaccines in myeloid leukemia immunotherapy

    Directory of Open Access Journals (Sweden)

    Lin Chen

    2013-02-01

    Full Text Available Abstract While chemotherapy and targeted therapy are successful in inducing the remission of myeloid leukemia as acute myeloid leukemia (AML and chronic myeloid leukemia (CML, the disease remains largely incurable. This observation is likely due to the drug resistance of leukemic cells, which are responsible for disease relapse. Myeloid leukemia vaccines may most likely be beneficial for eradicating minimal residual disease after treatment with chemotherapy or targeted therapy. Several targeted immunotherapies using leukemia vaccines have been heavily investigated in clinical and preclinical trials. This review will focus on peptides and DNA vaccines in the context of myeloid leukemias, and optimal strategies for enhancing the efficacy of vaccines based on myeloid leukemia immunization are also summarized.

  12. Evidence for the utility of the Bm86 antigen from Boophilus microplus in vaccination against other tick species.

    Science.gov (United States)

    de Vos, S; Zeinstra, L; Taoufik, O; Willadsen, P; Jongejan, F

    2001-01-01

    The Bm86 antigen, as originally identified in Boophilus microplus, is the basis of commercial tick vaccines against this tick species. The potential for using this antigen or homologues of the antigen in vaccination against other tick species has been assessed. We have conducted vaccine trials in cattle using the B. microplus-derived recombinant Bm86 vaccine (TickGARD) using pairs of vaccinated calves and control calves. These were infested with B. microplus and Boophilus decoloratus larvae simultaneously. For both species, the numbers of engorged female adult ticks, their weight and egg-laying capacity were all reduced, leading to a reduction in reproductive capacity of 74% for B. microplus and 70% for B. decoloratus. Hyalomma anatolicum anatolicum ticks were fed both as immatures as well as adults on vaccinated calves and non-vaccinated controls. There was an overall 50% reduction in the total weight of nymphs engorging on vaccinated calves, and a suggestion of a subsequent effect on feeding adults. For Hyalomma dromedarii there was a 95% reduction in the number of nymphs engorging and a further 55% reduction in weight of those ticks surviving. Rhipicephalus appendiculatus and Amblyomma variegatum ticks were fed simultaneously both as immatures and subsequently as adults. There was no evidence for a significant vaccination effect. Finally, the amino acid sequence of a Bm86 homologue found in H. a. anatolicum unequivocally demonstrated the conservation of this molecule in this species. Our strategy for the development of multivalent anti-tick vaccines is discussed in relation to these findings. PMID:11523920

  13. Structures of MART-126/27-35Peptide/HLA-A2 Complexes Reveal a Remarkable Disconnect between Antigen Structural Homology and T Cell Recognition

    Energy Technology Data Exchange (ETDEWEB)

    Borbulevych, Oleg Y; Insaidoo, Francis K; Baxter, Tiffany K; Powell, Jr., Daniel J.; Johnson, Laura A; Restifo, Nicholas P; Baker, Brian M [NIH; (Notre)

    2008-09-17

    Small structural changes in peptides presented by major histocompatibility complex (MHC) molecules often result in large changes in immunogenicity, supporting the notion that T cell receptors are exquisitely sensitive to antigen structure. Yet there are striking examples of TCR recognition of structurally dissimilar ligands. The resulting unpredictability of how T cells will respond to different or modified antigens impacts both our understanding of the physical bases for TCR specificity as well as efforts to engineer peptides for immunomodulation. In cancer immunotherapy, epitopes and variants derived from the MART-1/Melan-A protein are widely used as clinical vaccines. Two overlapping epitopes spanning amino acid residues 26 through 35 are of particular interest: numerous clinical studies have been performed using variants of the MART-1 26-35 decamer, although only the 27-35 nonamer has been found on the surface of targeted melanoma cells. Here, we show that the 26-35 and 27-35 peptides adopt strikingly different conformations when bound to HLA-A2. Nevertheless, clonally distinct MART-1{sub 26/27-35}-reactive T cells show broad cross-reactivity towards these ligands. Simultaneously, however, many of the cross-reactive T cells remain unable to recognize anchor-modified variants with very subtle structural differences. These dichotomous observations challenge our thinking about how structural information on unligated peptide/MHC complexes should be best used when addressing questions of TCR specificity. Our findings also indicate that caution is warranted in the design of immunotherapeutics based on the MART-1 26/27-35 epitopes, as neither cross-reactivity nor selectivity is predictable based on the analysis of the structures alone.

  14. Dendritic Cell Cancer Vaccines: From the Bench to the Bedside

    Directory of Open Access Journals (Sweden)

    Tamar Katz

    2014-10-01

    Full Text Available The recognition that the development of cancer is associated with acquired immunodeficiency, mostly against cancer cells themselves, and understanding pathways inducing this immunosuppression, has led to a tremendous development of new immunological approaches, both vaccines and drugs, which overcome this inhibition. Both “passive” (e.g. strategies relying on the administration of specific T cells and “active” vaccines (e.g. peptide-directed or whole-cell vaccines have become attractive immunological approaches, inducing cell death by targeting tumor-associated antigens. Whereas peptide-targeted vaccines are usually directed against a single antigen, whole-cell vaccines (e.g. dendritic cell vaccines are aimed to induce robust responsiveness by targeting several tumor-related antigens simultaneously. The combination of vaccines with new immuno-stimulating agents which target “immunosuppressive checkpoints” (anti-CTLA-4, PD-1, etc. is likely to improve and maintain immune response induced by vaccination.

  15. Antigen-displaying lipid-enveloped PLGA nanoparticles as delivery agents for a Plasmodium vivax malaria vaccine.

    Science.gov (United States)

    Moon, James J; Suh, Heikyung; Polhemus, Mark E; Ockenhouse, Christian F; Yadava, Anjali; Irvine, Darrell J

    2012-01-01

    The parasite Plasmodium vivax is the most frequent cause of malaria outside of sub-Saharan Africa, but efforts to develop viable vaccines against P. vivax so far have been inadequate. We recently developed pathogen-mimicking polymeric vaccine nanoparticles composed of the FDA-approved biodegradable polymer poly(lactide-co-glycolide) acid (PLGA) "enveloped" by a lipid membrane. In this study, we sought to determine whether this vaccine delivery platform could be applied to enhance the immune response against P. vivax sporozoites. A candidate malaria antigen, VMP001, was conjugated to the lipid membrane of the particles, and an immunostimulatory molecule, monophosphoryl lipid A (MPLA), was incorporated into the lipid membranes, creating pathogen-mimicking nanoparticle vaccines (VMP001-NPs). Vaccination with VMP001-NPs promoted germinal center formation and elicited durable antigen-specific antibodies with significantly higher titers and more balanced Th1/Th2 responses in vivo, compared with vaccines composed of soluble protein mixed with MPLA. Antibodies raised by NP vaccinations also exhibited enhanced avidity and affinity toward the domains within the circumsporozoite protein implicated in protection and were able to agglutinate live P. vivax sporozoites. These results demonstrate that these VMP001-NPs are promising vaccines candidates that may elicit protective immunity against P. vivax sporozoites.

  16. Antigen-displaying lipid-enveloped PLGA nanoparticles as delivery agents for a Plasmodium vivax malaria vaccine.

    Directory of Open Access Journals (Sweden)

    James J Moon

    Full Text Available The parasite Plasmodium vivax is the most frequent cause of malaria outside of sub-Saharan Africa, but efforts to develop viable vaccines against P. vivax so far have been inadequate. We recently developed pathogen-mimicking polymeric vaccine nanoparticles composed of the FDA-approved biodegradable polymer poly(lactide-co-glycolide acid (PLGA "enveloped" by a lipid membrane. In this study, we sought to determine whether this vaccine delivery platform could be applied to enhance the immune response against P. vivax sporozoites. A candidate malaria antigen, VMP001, was conjugated to the lipid membrane of the particles, and an immunostimulatory molecule, monophosphoryl lipid A (MPLA, was incorporated into the lipid membranes, creating pathogen-mimicking nanoparticle vaccines (VMP001-NPs. Vaccination with VMP001-NPs promoted germinal center formation and elicited durable antigen-specific antibodies with significantly higher titers and more balanced Th1/Th2 responses in vivo, compared with vaccines composed of soluble protein mixed with MPLA. Antibodies raised by NP vaccinations also exhibited enhanced avidity and affinity toward the domains within the circumsporozoite protein implicated in protection and were able to agglutinate live P. vivax sporozoites. These results demonstrate that these VMP001-NPs are promising vaccines candidates that may elicit protective immunity against P. vivax sporozoites.

  17. Membrane and envelope virus proteins co-expressed as lysosome associated membrane protein (LAMP) fused antigens: a potential tool to develop DNA vaccines against flaviviruses

    OpenAIRE

    Rafael Dhalia; Milton Maciel Jr.; Fábia S.P. Cruz; Isabelle F.T. Viana; Mariana L. Palma; Thomas August; Ernesto T.A. Marques Jr.

    2009-01-01

    Vaccination is the most practical and cost-effective strategy to prevent the majority of the flavivirus infection to which there is an available vaccine. However, vaccines based on attenuated virus can potentially promote collateral side effects and even rare fatal reactions. Given this scenario, the developent of alternative vaccination strategies such as DNA-based vaccines encoding specific flavivirus sequences are being considered. Endogenous cytoplasmic antigens, characteristically plasmi...

  18. Amiloride enhances antigen specific CTL by faciliting HBV DNA vaccine entry into cells.

    Directory of Open Access Journals (Sweden)

    Shuang Geng

    Full Text Available The induction of relatively weak immunity by DNA vaccines in humans can be largely attributed to the low efficiency of transduction of somatic cells. Although formulation with liposomes has been shown to enhance DNA transduction of cultured cells, little, if any, effect is observed on the transduction of somatic tissues and cells. To improve the rate of transduction, DNA vaccine delivery by gene gun and the recently developed electroporation techniques have been employed. We report here that to circumvent requirement for such equipment, amiloride, a drug that is prescribed for hypertension treatment, can accelerate plasmid entry into antigen presenting cells (APCs both in vitro and in vivo. The combination induced APCs more dramatically in both maturation and cytokine secretion. Amiloride enhanced development of full CD8 cytolytic function including induction of high levels of antigen specific CTL and expression of IFN-γ+perforin+granzymeB+ in CD8+ T cells. Thus, amiloride is a facilitator for DNA transduction into host cells which in turn enhances the efficiency of the immune responses.

  19. Molecular Design and Immunogenicity of a Multiple-epitope FMDV Antigen and DNA Vaccination

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This article reports the design and construction of a multiple-epitope foot and mouth disease virus (FMDV)antigen, designated as OAAT. This recombinant antigen consists of the structural protein VP1 genes from serotypes A and O FMDV, five major VP1 immunodominant epitopes from two genotypes of Asia1 serotype, and three Th2 epitopes originating from the nonstructural protein, three ABC gene and structural protein VP4 gene. Expressions of target gene from these plasmids in HeLa cells were verified by Western-blot. BALB/c mice were immunized intramuscularly with the DNA vaccines thrice every two weeks. We found that pA could induce simultaneously specific antibodies against serotypes A, Asia1, and O FMDV. Compared to those of the controls, the spots of FMDV-specific IFN-γ and cytotoxic activity from mice immunized with pA were significantly increased. pA provided full protection in 2/4 guinea pigs from challenge with FMDV O/NY00 and Asia1/YNBS/58, respectively. The results show that although pA did not give full protection in 100% immunized guinea pigs from challenge with type O and Asia1 FMDV, respectively, OAAT may be potential immunogen against FMDV and pA may be potential DNA vaccines against FMDV.

  20. Cross-protective peptide vaccine against influenza A viruses developed in HLA-A*2402 human immunity model.

    Directory of Open Access Journals (Sweden)

    Toru Ichihashi

    Full Text Available BACKGROUND: The virus-specific cytotoxic T lymphocyte (CTL induction is an important target for the development of a broadly protective human influenza vaccine, since most CTL epitopes are found on internal viral proteins and relatively conserved. In this study, the possibility of developing a strain/subtype-independent human influenza vaccine was explored by taking a bioinformatics approach to establish an immunogenic HLA-A24 restricted CTL epitope screening system in HLA-transgenic mice. METHODOLOGY/PRINCIPAL FINDINGS: HLA-A24 restricted CTL epitope peptides derived from internal proteins of the H5N1 highly pathogenic avian influenza A virus were predicted by CTL epitope peptide prediction programs. Of 35 predicted peptides, six peptides exhibited remarkable cytotoxic activity in vivo. More than half of the mice which were subcutaneously vaccinated with the three most immunogenic and highly conserved epitopes among three different influenza A virus subtypes (H1N1, H3N2 and H5N1 survived lethal influenza virus challenge during both effector and memory CTL phases. Furthermore, mice that were intranasally vaccinated with these peptides remained free of clinical signs after lethal virus challenge during the effector phase. CONCLUSIONS/SIGNIFICANCE: This CTL epitope peptide selection system can be used as an effective tool for the development of a cross-protective human influenza vaccine. Furthermore this vaccine strategy can be applicable to the development of all intracellular pathogens vaccines to induce epitope-specific CTL that effectively eliminate infected cells.

  1. PreS1 epitope recognition in newborns after vaccination with the third-generation Sci-B-Vac™ vaccine and their relation to the antibody response to hepatitis B surface antigen

    Directory of Open Access Journals (Sweden)

    Madalinski Kazimierz

    2009-01-01

    Full Text Available Abstract Background Sci-B-Vac™ is a recombinant, hepatitis B vaccine derived from a mammalian cell line and containing hepatitis B surface antigen (HBsAg as well as preS1 and preS2 antigens. Few studies have been performed on the antibody responses to preS1 in relation to the antibody to hepatitis B surface antigen (anti-HBs response during immunisation of healthy children with preS-containing vaccines. Results In this study 28 healthy newborns were randomly selected to receive either 2.5 ug or 5.0 ug of the Sci-B-Vac vaccine. Children received three doses of vaccine according to a 0-, 1-, 6-month scheme. Antibodies against the S-protein and three synthetic peptides mimicking three B-cell preS1 epitopes, (21–32 amino acid epitope, (32–47 amino acid epitope and the C-terminal (amino acid epitope 94–117 were determined at 6 and 9 months. Fourteen (50% of the 28 newborns had detectable levels of anti-preS1 (21–32 antibodies; 15 (54% were anti-preS1 (32–47 reactive and 12 (43% were anti-preS1 (94–117 reactive at 6 or 9 months after initiation of the vaccination. Significantly higher levels of anti-HBs were observed in the sera of patients with detectable anti-preS1 (32–47 reactivity (24 550 ± 7375 IU/L, mean ± SEM as compared with the non-reactive sera (5991 ± 1530 IU/L, p Conclusion Recognition of several preS1 epitopes, and in particular, the epitope contained within the second half of the hepatocyte binding site localised in the hepatitis B surface protein of the third-generation hepatitis B vaccine is accompanied by a more pronounced antibody response to the S-gene-derived protein in healthy newborns.

  2. Successful kidney transplantation from a hepatitis B surface antigen-positive donor to an antigen-negative recipient using a novel vaccination regimen.

    Science.gov (United States)

    Singh, Gurmukteshwar; Hsia-Lin, Andrea; Skiest, Daniel; Germain, Michael; O'Shea, Michael; Braden, Gregory

    2013-04-01

    Transplanting a kidney from a hepatitis B surface antigen (HBsAg)-positive donor to an HBsAg-negative recipient who is naturally immune has been successful in countries endemic for hepatitis B virus (HBV). However, in most of these cases, the donors were deceased. We present a report of a successful HBsAg-discordant kidney transplantation in the United States; in this case, a living donor kidney was transplanted to a vaccinated recipient. The wife of a 58-year-old HBsAg-negative man volunteered to donate a kidney to her husband. She had chronic hepatitis B but undetectable HBV DNA. She tested positive for HBsAg and antibody to hepatitis B core antigen, but hepatitis B e antigen was undetectable. The recipient failed to develop an antibody response to 3 doses of intramuscular recombinant HBV vaccine given in consecutive months. Immunity was induced by using biweekly intradermal vaccine. However, antibody titer tapered to vaccine resulted in a prolonged anamnestic response, allowing for successful living unrelated donor transplantation. During the 10 years since transplantation, the patient has continued to have normal liver function, with undetectable HBsAg and HBV DNA. Antibody titers to HBsAg slowly decreased to 5.8 mIU/mL during the 10 years. Transplant function has been well preserved. This approach to inducing long-term immunity for transplantation merits further study in the United States. PMID:23219109

  3. Increasing a Robust Antigen-Specific Cytotoxic T Lymphocyte Response by FMDV DNA Vaccination with IL-9 Expressing Construct

    OpenAIRE

    Qiang Zou; Bing Wu; Xiaodan He; Yizhi Zhang; Youmin Kang; Jin Jin; Hanqian Xu; Hu Liu; Bin Wang

    2010-01-01

    Various chemokines and cytokines as adjuvants can be used to improve efficacy of DNA vaccination. In this study, we sought to investigate if a DNA construct expressing IL-9 (designed as proV-IL9) as a molecular adjuvant enhance antigen specific immune responses elicited by the pcD-VP1 DNA vaccination. Mice immunized with pcD-VP1 combined with proV-IL9 developed a strong humoral response. In addition, the coinoculation induced significant higher level of antigen-specific cell proliferation and...

  4. Prophylaxis and Therapy of Inhalational Anthrax by a Novel Monoclonal Antibody to Protective Antigen That Mimics Vaccine-Induced Immunity

    OpenAIRE

    Vitale, Laura; Blanset, Diann; Lowy, Israel; O'Neill, Thomas; Goldstein, Joel; Little, Stephen F.; Andrews, Gerard P.; Dorough, Gary; Taylor, Ronald K.; Keler, Tibor

    2006-01-01

    The neutralizing antibody response to the protective antigen (PA) component of anthrax toxin elicited by approved anthrax vaccines is an accepted correlate for vaccine-mediated protection against anthrax. We reasoned that a human anti-PA monoclonal antibody (MAb) selected on the basis of superior toxin neutralization activity might provide potent protection against anthrax. The fully human MAb (also referred to as MDX-1303 or Valortim) was chosen from a large panel of anti-PA human MAbs gener...

  5. Serological Correlate of Protection in Guinea Pigs for a Recombinant Protective Antigen Anthrax Vaccine Produced from Bacillus brevis

    OpenAIRE

    Chun, Jeong-Hoon; Choi, On-Jee; Cho, Min-Hee; Hong, Kee-Jong; Seong, Won Keun; Oh, Hee-Bok; Rhie, Gi-eun

    2012-01-01

    Objective Recombinant protective antigen (rPA) is the active pharmaceutical ingredient of a second generation anthrax vaccine undergoing clinical trials both in Korea and the USA. By using the rPA produced from Bacillus brevis pNU212 expression system, correlations of serological immune response to anthrax protection efficacy were analyzed in a guinea pig model. Methods Serological responses of rPA anthrax vaccine were investigated in guinea pigs that were given single or two injections (inte...

  6. Impact of the RTS,S malaria vaccine candidate on naturally acquired antibody responses to multiple asexual blood stage antigens.

    Directory of Open Access Journals (Sweden)

    Joseph J Campo

    Full Text Available BACKGROUND: Partial protective efficacy lasting up to 43 months after vaccination with the RTS,S malaria vaccine has been reported in one cohort (C1 of a Phase IIb trial in Mozambique, but waning efficacy was observed in a smaller contemporaneous cohort (C2. We hypothesized that low dose exposure to asexual stage parasites resulting from partial pre-erythrocytic protection afforded by RTS,S may contribute to long-term vaccine efficacy to clinical disease, which was not observed in C2 due to intense active detection of infection and treatment. METHODOLOGY/PRINCIPAL FINDINGS: Serum collected 6 months post-vaccination was screened for antibodies to asexual blood stage antigens AMA-1, MSP-1(42, EBA-175, DBL-α and variant surface antigens of the R29 laboratory strain (VSA(R29. Effect of IgG on the prospective hazard of clinical malaria was estimated. No difference was observed in antibody levels between RTS,S and control vaccine when all children aged 1-4 years at enrollment in both C1 and C2 were analyzed together, and no effects were observed between cohort and vaccine group. RTS,S-vaccinated children <2 years of age at enrollment had lower levels of IgG for AMA-1 and MSP-1(42 (p<0.01, all antigens, while no differences were observed in children ≥2 years. Lower risk of clinical malaria was associated with high IgG to EBA-175 and VSA(R29 in C2 only (Hazard Ratio [HR]: 0.76, 95% CI 0.66-0.88; HR: 0.75, 95% CI 0.62-0.92, respectively. CONCLUSIONS: Vaccination with RTS,S modestly reduces anti-AMA-1 and anti-MSP-1 antibodies in very young children. However, for antigens associated with lower risk of clinical malaria, there were no vaccine group or cohort-specific effects, and age did not influence antibody levels between treatment groups for these antigens. The antigens tested do not explain the difference in protective efficacy in C1 and C2. Other less-characterized antigens or VSA may be important to protection. TRIAL REGISTRATION: Clinical

  7. Hepatitis B vaccination coverage and risk factors associated with incomplete vaccination of children born to hepatitis B surface antigen-positive mothers, Denmark, 2006 to 2010.

    Science.gov (United States)

    Kunoee, Asja; Nielsen, Jens; Cowan, Susan

    2016-01-01

    In Denmark, universal screening of pregnant women for hepatitis B has been in place since November 2005, with the first two years as a trial period with enhanced surveillance. It is unknown what the change to universal screening without enhanced surveillance has meant for vaccination coverage among children born to hepatitis B surface antigen (HBsAg)-positive mothers and what risk factors exist for incomplete vaccination. This retrospective cohort study included 699 children of mothers positive for HBsAg. Information on vaccination and risk factors was collected from central registers. In total, 93% (651/699) of the children were vaccinated within 48 hours of birth, with considerable variation between birthplaces. Only 64% (306/475) of the children had received all four vaccinations through their general practitioner (GP) at the age of two years, and 10% (47/475) of the children had received no hepatitis B vaccinations at all. Enhanced surveillance was correlated positively with coverage of birth vaccination but not with coverage at the GP. No or few prenatal examinations were a risk factor for incomplete vaccination at the GP. Maternity wards and GPs are encouraged to revise their vaccination procedures and routines for pregnant women, mothers with chronic HBV infection and their children.

  8. cDNA library construction and isolation of genes for candidate vaccine antigens from Chrysomya bezziana (the Old World Screwworm fly

    Directory of Open Access Journals (Sweden)

    Tony Voucolo

    2000-10-01

    Full Text Available The construction and use of cDNA libraries for the isolation of genes encoding candidate antigens for use in a recombinant vaccine against Chrysomya bezziana is described. RNA was isolated and mRNA purified from first and third instar larvae of Chrysomya bezziana and used in the synthesis of two cDNA libraries in the bacteriophage vector λ ZAP express®. These libraries were screened using Digoxigenin-labeled DNA probes obtained from two independent approaches. First, a homolog approach used probes designed from previously characterized peritrophic membrane genes identified from the related myiasis fly, Lucilia cuprina. Secondly, a de novo approach used amino-terminal and internal peptide sequence information derived from purified Chrysomya bezziana peritrophic membrane proteins to generate DNA probes. Three peritrophic membrane genes were identified and characterized. Chrysomya bezziana peritrophin-48 was identified using the homolog approach and, Chrysomya bezziana peritrophin-15 and Chrysomya bezziana peritrophin-42 were identified using the de novo approach. The identification of these genes as encoding candidate antigens against Chrysomya bezziana has allowed the production of recombinant proteins for use in vaccination trials

  9. Preparation and testing of a Haemophilus influenzae Type b/Hepatitis B surface antigen conjugate vaccine.

    Science.gov (United States)

    An, So Jung; Woo, Joo Sung; Chae, Myung Hwa; Kothari, Sudeep; Carbis, Rodney

    2015-03-24

    The majority of conjugate vaccines focus on inducing an antibody response to the polysaccharide antigen and the carrier protein is present primarily to induce a T-cell dependent response. In this study conjugates consisting of poly(ribosylribitolphosphate) (PRP) purified from Haemophilus influenzae Type b bound to Hepatitis B virus surface antigen (HBsAg) virus like particles were prepared with the aim of inducing an antibody response to not only the PRP but also the HBsAg. A conjugate consisting of PRP bound to HBsAg via an adipic acid dihydrazide (ADH) spacer induced strong IgG antibodies to both the PRP and HBsAg. When conjugation was performed without the ADH spacer the induction of an anti-PRP response was equivalent to that seen by conjugate with the ADH spacer, however, a negligible anti-HBsAg response was induced. For comparison, PRP was conjugated to diphtheria toxoid (DT) and Vi polysaccharide purified from Salmonella Typhi conjugated to HBsAg both using an ADH spacer. The PRPAH-DT conjugate induced strong anti-PRP and anti-DT responses, the Vi-AHHBsAg conjugate induced a good anti-HBsAg response but not as strong as that induced by the PRPAH-HBsAg conjugate. This study demonstrated that in mice it was possible to induce robust antibody responses to both polysaccharide and carrier protein provided the conjugate has certain physico-chemical properties. A PRPAH-HBsAg conjugate with the capacity to induce anti-PRP and anti-HBsAg responses could be incorporated into a multivalent pediatric vaccine and simplify formulation of such a vaccine.

  10. Subcomponent vaccine based on CTA1-DD adjuvant with incorporated UreB class II peptides stimulates protective Helicobacter pylori immunity.

    Directory of Open Access Journals (Sweden)

    John G Nedrud

    Full Text Available A mucosal vaccine against Helicobacter pylori infection could help prevent gastric cancers and peptic ulcers. While previous attempts to develop such a vaccine have largely failed because of the requirement for safe and effective adjuvants or large amounts of well defined antigens, we have taken a unique approach to combining our strong mucosal CTA1-DD adjuvant with selected peptides from urease B (UreB. The protective efficacy of the selected peptides together with cholera toxin (CT was first confirmed. However, CT is a strong adjuvant that unfortunately is precluded from clinical use because of its toxicity. To circumvent this problem we have developed a derivative of CT, the CTA1-DD adjuvant, that has been found safe in non-human primates and equally effective compared to CT when used intranasally. We genetically fused the selected peptides into the CTA1-DD plasmid and found after intranasal immunizations of Balb/c mice using purified CTA1-DD with 3 copies of an H. pylori urease T cell epitope (CTA1-UreB3T-DD that significant protection was stimulated against a live challenge infection. Protection was, however, weaker than with the gold standard, bacterial lysate+CT, but considering that we only used a single epitope in nanomolar amounts the results convey optimism. Protection was associated with enhanced Th1 and Th17 immunity, but immunizations in IL-17A-deficient mice revealed that IL-17 may not be essential for protection. Taken together, we have provided evidence for the rational design of an effective mucosal subcomponent vaccine against H. pylori infection based on well selected protective epitopes from relevant antigens incorporated into the CTA1-DD adjuvant platform.

  11. Structure of the meningococcal vaccine antigen NadA and epitope mapping of a bactericidal antibody.

    Science.gov (United States)

    Malito, Enrico; Biancucci, Marco; Faleri, Agnese; Ferlenghi, Ilaria; Scarselli, Maria; Maruggi, Giulietta; Lo Surdo, Paola; Veggi, Daniele; Liguori, Alessia; Santini, Laura; Bertoldi, Isabella; Petracca, Roberto; Marchi, Sara; Romagnoli, Giacomo; Cartocci, Elena; Vercellino, Irene; Savino, Silvana; Spraggon, Glen; Norais, Nathalie; Pizza, Mariagrazia; Rappuoli, Rino; Masignani, Vega; Bottomley, Matthew James

    2014-12-01

    Serogroup B Neisseria meningitidis (MenB) is a major cause of severe sepsis and invasive meningococcal disease, which is associated with 5-15% mortality and devastating long-term sequelae. Neisserial adhesin A (NadA), a trimeric autotransporter adhesin (TAA) that acts in adhesion to and invasion of host epithelial cells, is one of the three antigens discovered by genome mining that are part of the MenB vaccine that recently was approved by the European Medicines Agency. Here we present the crystal structure of NadA variant 5 at 2 Å resolution and transmission electron microscopy data for NadA variant 3 that is present in the vaccine. The two variants show similar overall topology with a novel TAA fold predominantly composed of trimeric coiled-coils with three protruding wing-like structures that create an unusual N-terminal head domain. Detailed mapping of the binding site of a bactericidal antibody by hydrogen/deuterium exchange MS shows that a protective conformational epitope is located in the head of NadA. These results provide information that is important for elucidating the biological function and vaccine efficacy of NadA.

  12. 预防肿瘤术后复发和转移的最新疗法 :热休克蛋白 /肽复合物疫苗的研究与应用%A new strategy to prevent cancer recurrence and metastasis after operation:research and application of heat shock protein/peptides complex vaccine

    Institute of Scientific and Technical Information of China (English)

    陈继营; 袁玫; 卢世璧

    2002-01-01

    Deepened understanding of the mechanism involved in the activation of T cells and improved molecular biology techniques have brought a promising strategy to active a patient's immune system to prevent tumor recurrence and metastasis. Heat shock proteins (HSPs) are chaperones of peptides,It can elicit array of immune responses,such as:present tumor antigens to T cells, stimulate antigen presenting cells to secrete cytokines,mediate maturation of dentritic cells,active NK cells and/T cells.Extract HSP/peptides complex from tumor cells can be used as a polyvalent vaccine for treatment of cancers,The elicited antigen specific immune response is restricted to the tumor from which the HSPs are purified.HSP/peptides complex vaccine has been started in third clinical trials.The rationale,feasibility,advantages and safety of this new approach were discussed.

  13. H1N1 viral proteome peptide microarray predicts individuals at risk for H1N1 infection and segregates infection versus Pandemrix(®) vaccination.

    Science.gov (United States)

    Ambati, Aditya; Valentini, Davide; Montomoli, Emanuele; Lapini, Guilia; Biuso, Fabrizio; Wenschuh, Holger; Magalhaes, Isabelle; Maeurer, Markus

    2015-07-01

    A high content peptide microarray containing the entire influenza A virus [A/California/08/2009(H1N1)] proteome and haemagglutinin proteins from 12 other influenza A subtypes, including the haemagglutinin from the [A/South Carolina/1/1918(H1N1)] strain, was used to gauge serum IgG epitope signatures before and after Pandemrix(®) vaccination or H1N1 infection in a Swedish cohort during the pandemic influenza season 2009. A very narrow pattern of pandemic flu-specific IgG epitope recognition was observed in the serum from individuals who later contracted H1N1 infection. Moreover, the pandemic influenza infection generated IgG reactivity to two adjacent epitopes of the neuraminidase protein. The differential serum IgG recognition was focused on haemagglutinin 1 (H1) and restricted to classical antigenic sites (Cb) in both the vaccinated controls and individuals with flu infections. We further identified a novel epitope VEPGDKITFEATGNL on the Ca antigenic site (251-265) of the pandemic flu haemagglutinin, which was exclusively recognized in serum from individuals with previous vaccinations and never in serum from individuals with H1N1 infection (confirmed by RNA PCR analysis from nasal swabs). This epitope was mapped to the receptor-binding domain of the influenza haemagglutinin and could serve as a correlate of immune protection in the context of pandemic flu. The study shows that unbiased epitope mapping using peptide microarray technology leads to the identification of biologically and clinically relevant target structures. Most significantly an H1N1 infection induced a different footprint of IgG epitope recognition patterns compared with the pandemic H1N1 vaccine.

  14. Identification and characterization of profilin antigen among Babesia species as a common vaccine candidate against babesiosis.

    Science.gov (United States)

    Munkhjargal, Tserendorj; Aboge, Gabriel Oluga; Ueno, Akio; Aboulaila, Mahmoud; Yokoyama, Naoaki; Igarashi, Ikuo

    2016-07-01

    We have characterized a member of the profilin (PROF) family protein as a common antigen in three pathogens-Babesia bovis (B. bovis), Babesia bigemina (B. bigemina), and Babesia microti (B. microti)-and evaluated its immunogenic and cross-protective properties against a challenge infection with B. microti in BALB/c mice. The recombinant PROF proteins of B. bovis, B. bigemina, and B. microti were successfully expressed in Escherichia coli (E. coli) as soluble GST fusion proteins (rBboPROF, rBbigPROF, and rBmPROF, respectively), and they were found to be antigenic. On probing with mouse anti-rPROF serum, green fluorescence was observed on the parasites' cytosols by confocal laser microscopy. Immunization regimes in BALB/c mice using rPROFs induced cross-protective immunity against B. microti infection based on high levels of cytokines and immunoglobulin (IgG) titers, a reduction in peak parasitemia levels, and earlier clearance of the parasite as compared with control mice. The findings of the present study indicate that PROF is a common antigen among bovine and murine Babesia parasites, and it might be used as a common vaccine candidate against babesiosis. PMID:27003460

  15. A Delayed Type Hypersensitivity (DTH) Skin Reaction to Hepatitis B Surface Antigen (HBsAg) and Intradermal Hepatitis B Vaccination

    OpenAIRE

    Nagafuchi, Seiho; Kashiwagi, Seizaburo; Hayashi, Jun; Katsuta, Hitoshi; Ikematsu, Hideyuki; Harada, Mine

    2004-01-01

    The significance of a delayed type hypersensitivity skin reaction to hepatitis B surface antigen (HBsAg) (HBs-DTH) in type B viral hepatitis (VHB) and in intradermal hepatitis B (HB) vaccination is reviewed. HBs-DTH could be developed by the intradermal injection of HB vaccine in anti-HBs positive people and also in persons immunized with HB vaccine. Thus, HBs-DTH could serve as a useful marker for the acquisition of an active Thl type immunoreactivity to HBsAg. HBs-DTH was absent in patients...

  16. Infection with Plasmodium berghei Boosts Antibody Responses Primed by a DNA Vaccine Encoding Gametocyte Antigen Pbs48/45

    OpenAIRE

    Haddad, Diana; Maciel, Jorge; Kumar, Nirbhay

    2006-01-01

    An important consideration in the development of a malaria vaccine for individuals living in areas of endemicity is whether vaccine-elicited immune responses can be boosted by natural infection. To investigate this question, we used Plasmodium berghei ANKA blood-stage parasites for the infection of mice that were previously immunized with a DNA vaccine encoding the P. berghei sexual-stage antigen Pbs48/45. Intramuscular immunization in mice with one or two doses of DNA-Pbs48/45 or of empty DN...

  17. Improved cell mediated immune responses after successful re-vaccination of non-responders to the hepatitis B virus surface antigen (HBsAg) vaccine using the combined hepatitis A and B vaccine.

    Science.gov (United States)

    Nyström, Jessica; Cardell, Kristina; Björnsdottir, Thora Björg; Fryden, Aril; Hultgren, Catharina; Sällberg, Matti

    2008-11-01

    We successfully re-vaccinated hepatitis B virus (HBV) vaccine non-responders using a double dose of the combined hepatitis A virus (HAV) and HBV vaccine. The hope was to improve priming of hepatitis B surface antigen (HBsAg)-specific cell mediated immune response (CMI) by an increased antigen dose and a theoretical adjuvant-effect from the local presence of a HAV-specific CMI. A few non-responders had a detectable HBsAg-specific CMI before re-vaccination. An in vitro detectable HBsAg-specific CMI was primed equally effective in non-responders (58%) as in first time vaccine recipients (68%). After the third dose a weak, albeit significant, association was observed between the magnitude of HBsAg-specific proliferation and anti-HBs levels. This regimen improves the priming of HBsAg-specific CMIs and antibodies.

  18. Identification of an erythrocyte binding peptide from the erythrocyte binding antigen, EBA-175, which blocks parasite multiplication and induces peptide-blocking antibodies

    DEFF Research Database (Denmark)

    Jakobsen, P H; Heegaard, P M; Koch, C;

    1998-01-01

    A biotinylated peptide covering a sequence of 21 amino acids (aa) from the erythrocyte binding antigen (EBA-175) of Plasmodium falciparum bound to human glycophorin A, an erythrocyte receptor for merozoites, as demonstrated by enzyme-linked immunosorbent assay (ELISA) and to erythrocytes as demon......A biotinylated peptide covering a sequence of 21 amino acids (aa) from the erythrocyte binding antigen (EBA-175) of Plasmodium falciparum bound to human glycophorin A, an erythrocyte receptor for merozoites, as demonstrated by enzyme-linked immunosorbent assay (ELISA) and to erythrocytes...... as demonstrated by flow cytometry analysis. The peptide, EBA(aa1076-96), also bound to desialylated glycophorin A and glycophorin B when tested by ELISA. The peptide blocked parasite multiplication in vitro. The glycophorin A binding sequence was further delineated to a 12-aa sequence, EBA(aa1085-96), by testing...... the binding of a range of truncated peptides to immobilized glycophorin A. Our data indicate that EBA(aa1085-96) is part of a ligand on the merozoite for binding to erythrocyte receptors. This binding suggests that the EBA(aa1085-96) peptide is involved in a second binding step, independent of sialic acid...

  19. Identification of an erythrocyte binding peptide from the erythrocyte binding antigen, EBA-175, which blocks parasite multiplication and induces peptide-blocking antibodies

    DEFF Research Database (Denmark)

    Jakobsen, P.H.; Heegaard, Peter M. H.; Koch, C.;

    1998-01-01

    A biotinylated peptide covering a sequence of 21 amino acids (aa) from the erythrocyte binding antigen (EBA-175) of Plasmodium falciparum bound to human glycophorin A, an erythrocyte receptor for merozoites, as demonstrated by enzyme-linked immunosorbent assay (ELISA) and to erythrocytes as demon......A biotinylated peptide covering a sequence of 21 amino acids (aa) from the erythrocyte binding antigen (EBA-175) of Plasmodium falciparum bound to human glycophorin A, an erythrocyte receptor for merozoites, as demonstrated by enzyme-linked immunosorbent assay (ELISA) and to erythrocytes...... as demonstrated by flow cytometry analysis. The peptide, EBA(aa1076-96), also bound to desialylated glycophorin A and glycophorin B when tested by ELISA, The peptide blocked parasite multiplication in vitro. The glycophorin A binding sequence was further delineated to a 12-aa sequence, EBA(aa1085-96), by testing...... the binding of a range of truncated peptides to immobilized glycophorin A. Our data indicate that EBA(aa1085-96) is part of a ligand on the merozoite for binding to erythrocyte receptors. This binding suggests that the EBA(aa1085-96) peptide is involved in a second binding step, independent of sialic acid...

  20. Distinct uptake mechanisms but similar intracellular processing of two different toll-like receptor ligand-peptide conjugates in dendritic cells.

    NARCIS (Netherlands)

    Khan, S.; Bijker, M.S.; Weterings, J.J.; Tanke, H.J.; Adema, G.J.; Hall, T. van; Drijfhout, J.W.; Melief, C.J.; Overkleeft, H.S.; Marel, G.A. van der; Filippov, D.V.; Burg, S.H. van der; Ossendorp, F.

    2007-01-01

    Covalent conjugation of Toll-like receptor ligands (TLR-L) to synthetic antigenic peptides strongly improves antigen presentation in vitro and T lymphocyte priming in vivo. These molecularly well defined TLR-L-peptide conjugates, constitute an attractive vaccination modality, sharing the peptide ant

  1. Expression of HSV-1 ICP0 Antigen Peptide in Prokaryotic Cells and Preparation of Specific Antibody

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    As an immediate-early protein of herpes simplex virus, infected-cell polypeptide 0 (ICP0) exhibits complicated interactions with host cells, and its regulatory function on gene expression is of great importance. Since the ICP0 encoding sequence contains many rare codons which are absent in E.coli, and ICP0 is highly unstable in prokaryotic cells, expression of entire ICP0 in prokaryotic cells has never been reported. In order to further investigate the function of ICP0, a recombinant plasmid was constructed by subcloning a cDNA fragment encoding an amino-terminal of 105 residues of the ICP0 protein into pGEX-5x-1 vector. The resulting GST-105 fusion antigen peptide was expressed with high efficiency in E.coli. Antibodies prepared after the immunization of mice with purified fusion protein can recognize not only the denatured ICP0 protein, but also the native ICP0 protein with normal biological conformation.

  2. Mucosal vaccine delivery of antigens tightly bound to an adjuvant particle made from food-grade bacteria

    NARCIS (Netherlands)

    van Roosmalen, ML; Kanninga, R; El Khattabi, M; Neef, J; Audouy, S; Bosma, T; Kuipers, A; Post, E; Steen, A; Kok, J; Buist, G; Kuipers, OP; Robillard, G; Leenhouts, K

    2006-01-01

    Mucosal immunization with subunit vaccines requires new types of antigen delivery vehicles and adjuvants for optimal immune responses. We have developed a non-living and non-genetically modified gram-positive bacterial delivery particle (GEM) that has built-in adjuvant activity and a high loading ca

  3. Cancer Vaccines: A Brief Overview.

    Science.gov (United States)

    Thomas, Sunil; Prendergast, George C

    2016-01-01

    Vaccine approaches for cancer differ from traditional vaccine approaches for infectious disease in tending to focus on clearing active disease rather than preventing disease. In this review, we provide a brief overview of different types of vaccines and adjuvants that have been investigated for the purpose of controlling cancer burdens in patients, some of which are approved for clinical use or in late-stage clinical trials, such as the personalized dendritic cell vaccine sipuleucel-T (Provenge) and the recombinant viral prostate cancer vaccine PSA-TRICOM (Prostvac-VF). Vaccines against human viruses implicated in the development and progression of certain cancers, such as human papillomavirus in cervical cancer, are not considered here. Cancers express "altered self" antigens that tend to induce weaker responses than the "foreign" antigens expressed by infectious agents. Thus, immune stimulants and adjuvant approaches have been explored widely. Vaccine types considered include autologous patient-derived immune cell vaccines, tumor antigen-expressing recombinant virus vaccines, peptide vaccines, DNA vaccines, and heterologous whole-cell vaccines derived from established human tumor cell lines. Opportunities to develop effective cancer vaccines may benefit from seminal recent advances in understanding how immunosuppressive barricades are erected by tumors to mediate immune escape. In particular, targeted ablation of these barricades with novel agents, such as the immune checkpoint drug ipilimumab (anti-CTLA-4) approved recently for clinical use, may offer significant leverage to vaccinologists seeking to control and prevent malignancy.

  4. The Expression of Sperm Membrane Peptide-Hepatitis B Surface Antigen Fusion Protein with Recombinant Vaccinia Virus

    Institute of Scientific and Technical Information of China (English)

    杨晓鸣; 赵峰; 严缘昌; 李光地; 汪垣

    1998-01-01

    A synthetic oligonucleotide, HSD-2a, encoding a peptide segment of the extracellular domain of a human sperm membrane protein, YWK-Ⅱ, was fused with hepatitis B surface antigen gene (HBs gene). The fused gene was then cloned to pUC18 plasmid.

  5. Differences in immune responses against Leishmania induced by infection and by immunization with killed parasite antigen: implications for vaccine discovery.

    Science.gov (United States)

    Mendonça, Sergio C F

    2016-01-01

    The leishmaniases are a group of diseases caused by different species of the protozoan genus Leishmania and transmitted by sand fly vectors. They are a major public health problem in almost all continents. There is no effective control of leishmaniasis and its geographical distribution is expanding in many countries. Great effort has been made by many scientists to develop a vaccine against leishmaniasis, but, so far, there is still no effective vaccine against the disease. The only way to generate protective immunity against leishmaniasis in humans is leishmanization, consisting of the inoculation of live virulent Leishmania as a means to acquire long-lasting immunity against subsequent infections. At present, all that we know about human immune responses to Leishmania induced by immunization with killed parasite antigens came from studies with first generation candidate vaccines (killed promastigote extracts). In the few occasions that the T cell-mediated immune responses to Leishmania induced by infection and immunization with killed parasite antigens were compared, important differences were found both in humans and in animals. This review discusses these differences and their relevance to the development of a vaccine against leishmaniasis, the major problems involved in this task, the recent prospects for the selection of candidate antigens and the use of attenuated Leishmania as live vaccines. PMID:27600664

  6. Oral immunization of broiler chickens against necrotic enteritis with an attenuated Salmonella vaccine vector expressing Clostridium perfringens antigens.

    Science.gov (United States)

    Kulkarni, R R; Parreira, V R; Sharif, S; Prescott, J F

    2008-08-01

    Necrotic enteritis (NE) in broiler chickens is caused by Clostridium perfringens but currently no effective vaccine is available. Our previous study showed that certain C. perfringens secreted proteins when administered intramuscularly protected chickens against experimental infection. In the current study, genes encoding three C. perfringens proteins: fructose-biphosphate-aldolase (FBA), pyruvate:ferredoxin-oxidoreductase (PFOR) and hypothetical protein (HP), were cloned into an avirulent Salmonella enterica sv. typhimurium vaccine vector. Broiler chickens immunized orally with recombinant Salmonella expressing FBA or HP proteins were significantly protected against NE challenge. Immunized birds developed serum and mucosal antibodies to both clostridial and Salmonella antigens. This study showed the oral immunizing ability of two C. perfringens antigens against NE in broiler chickens through an attenuated Salmonella vaccine vector. PMID:18597901

  7. Yeast surface display of a noncovalent MHC class II heterodimer complexed with antigenic peptide.

    Science.gov (United States)

    Boder, Eric T; Bill, Jerome R; Nields, Andrew W; Marrack, Philippa C; Kappler, John W

    2005-11-20

    Microbial protein display technologies have enabled directed molecular evolution of binding and stability properties in numerous protein systems. In particular, dramatic improvements to antibody binding affinity and kinetics have been accomplished using these tools in recent years. Examples of successful application of display technologies to other immunological proteins have been limited to date. Herein, we describe the expression of human class II major histocompatibility complex allele (MHCII) HLA-DR4 on the surface of Saccharomyces cerevisiae as a noncovalently associated heterodimer. The yeast-displayed MHCII is fully native as assessed by binding of conformationally specific monoclonal antibodies; failure of antibodies specific for empty HLA-DR4 to bind yeast-displayed protein indicates antigenic peptide is bound. This report represents the first example of a noncovalent protein dimer displayed on yeast and of successful display of wild-type MHCII. Results further point to the potential for using yeast surface display for engineering and analyzing the antigen binding properties of MHCII.

  8. TCR affinity for thymoproteasome-dependent positively selecting peptides conditions antigen responsiveness in CD8(+) T cells.

    Science.gov (United States)

    Takada, Kensuke; Van Laethem, Francois; Xing, Yan; Akane, Kazuyuki; Suzuki, Haruhiko; Murata, Shigeo; Tanaka, Keiji; Jameson, Stephen C; Singer, Alfred; Takahama, Yousuke

    2015-10-01

    In the thymus, low-affinity T cell antigen receptor (TCR) engagement facilitates positive selection of a useful T cell repertoire. Here we report that TCR responsiveness of mature CD8(+) T cells is fine tuned by their affinity for positively selecting peptides in the thymus and that optimal TCR responsiveness requires positive selection on major histocompatibility complex class I-associated peptides produced by the thymoproteasome, which is specifically expressed in the thymic cortical epithelium. Thymoproteasome-independent positive selection of monoclonal CD8(+) T cells results in aberrant TCR responsiveness, homeostatic maintenance and immune responses to infection. These results demonstrate a novel aspect of positive selection, in which TCR affinity for positively selecting peptides produced by thymic epithelium determines the subsequent antigen responsiveness of mature CD8(+) T cells in the periphery.

  9. Cytokines Expression Profile and Kinetics of Peste des petits ruminants Virus Antigen and Antibody in Infected and Vaccinated Goats

    Institute of Scientific and Technical Information of China (English)

    Arun Patel; Kaushal Kishor Rajak; Vinayagamurthy Balamurugan; Arnab Sen; Shashi Bhusan Sudhakar; Veerakyathappa Bhanuprakash; Raj Kumar Singh; Awadh Bihari Pandey

    2012-01-01

    The present study deals with the co-ordination of cytokine(IL-4 and IFN-γ) expression and kinetics of peste des petits ruminants(PPR) virus antigen and antibody in PPRV infected and vaccinated goats.The infected animals exhibited mixed cytokine(both TH1 and TH2) responses in the initial phase of the disease.The infected and dead goats had increased IFN-γ response before their death; while IL-4 remained at the base level.The cytokine expression in recovered animals was almost similar to that of vaccinated ones,where a unique biphasic response of IL-4 expression was observed with an up-regulation of IFN-γ on 7th days post vaccination(dpv).Analysis of PPR virus antigen and antibody kinetics in different components of blood from infected and vaccinated animals revealed that the PPR virus antigen load was highest in plasma followed by serum and blood of the infected animals,whereas vaccinated animals showed only marginal positivity on 9th dpv.The antibody titer was high in serum followed by plasma and blood in both vaccinated and infected animals.Therefore,it is inferred that the presence of antigen and antibody were significant with the expression of cytokine,and that a decreased response of IL-4 was noticed during intermediate phase of the disease i.e.,7 to 12th days post infection(dpi).This indicates the ability to mount a functional TH2 response after 14th dpi could be a critical determinant in deciding the survival of the PPR infected animal.

  10. A DNA vaccine encoding mutated HPV58 mE6E7-Fc-GPI fusion antigen and GM-CSF and B7.1

    Directory of Open Access Journals (Sweden)

    Wang H

    2015-10-01

    Full Text Available He Wang,1 Jiyun Yu,2 Li Li1 1Department of Gynecologic Oncology, Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi, 2Institute of Basic Medical Sciences, Academy of Military Medical Sciences, Beijing, People’s Republic of China Background: Persistent infection with high-risk human papillomavirus (HPV is a predominant cause of cervical cancer, and HPV58 is the third most common virus detected in the patients with cervical cancer in Asia. E6 and E7 are the viral oncogenes which are constitutively expressed in HPV-associated tumor cells and can be used as target antigens for related immunotherapy. In this study, we modified the HPV58 E6 and E7 oncogenes to eliminate their oncogenic potential and constructed a recombinant DNA vaccine that coexpresses the sig-HPV58 mE6E7-Fc-GPI fusion antigen in addition to granulocyte-macrophage colony-stimulating factor (GM-CSF and B7.1 as molecular adjuvants (PVAX1-HPV58 mE6E7FcGB for the treatment of HPV58 (+ cancer. Methods: PVAX1-HPV58 mE6E7FcGB recombinant DNA vaccine was constructed to express a fusion protein containing a signal peptide, a modified HPV58 mE6E7 gene, and human IgG Fc and glycosylphosphatidylinositol (GPI-anchoring sequences using the modified DNA vaccine vector PVAX1-IRES-GM/B7.1 that coexpresses GM-CSF, and B7.1. C57BL/6 mice were challenged by HPV58 E6E7-expressing B16-HPV58 E6E7 cells, followed by immunization by PVAX1-HPV58 mE6E7FcGB vaccine on days 7, 14, 21 after tumor challenge. The cellular immune responses in immunized mice were assessed by measuring IFN-γ production in splenocytes upon stimulation by HPV58 E6E7-GST protein and the lysis of B16-HPV58 E6E7 target cells by splenocytes after restimulation with HPV58 E6E7-GST protein. The antitumor efficacy was evaluated by monitoring the growth of the tumor. Results: PVAX1-HPV58 mE6E7FcGB elicited varying levels of IFN-lsgdB58onn T-cell immune responses and lysis of target cell in mice in response to the

  11. Development of hepatitis C virus vaccine using hepatitis B core antigen as immuno-carrier

    Institute of Scientific and Technical Information of China (English)

    Jia-Yu Chen; Fan Li

    2006-01-01

    AIM: To develop hepatitis C virus (HCV) vaccine using HBcAg as the immuno-carrier to express HCV T epitope and to investigate its immunogenicity in mice.METHODS: We constructed the plasmid pTrc-coreNheI using gene engineering technique, constructed the pcDNA3.1-coreNheI-GFP plasmid with GFP as the reporter gene, and transfected them into Hela cells.The expression of GFP was observed under confocal microscopy and the feasibility of using HBcAg as an immuno-carrier vaccine was studied. pTrc-core gene with a synthetic T epitope antigen gene of HCV (35-44aa) was fused and expressed in the plasmid pTrccore-HCV (T). For the fusion of the HBcAg-T protein,sucrose, density gradient centrifugation was used, and its molecular weight and purity were analyzed by SDSPAGE. Then balb/c mice were immunized by the plasmid with the HBcAg (expressed by pTrc-core) protein as control. The tumor regression potential was investigated in mice and evaluated at appropriate time. After three times of immunization, the peripheral blood and spleen of vaccinated mice were collected. HBcAb was detected by ELISA, and nonspecific T lymphocyte proliferation and response of splenocytes were respectively examined by MTT assay. T cell subset of blood and spleen were detected by FACS.RESULTS: GFP was successfully expressed. Tumor regression trial showed that no tumor formation was found in the group receiving immunization, while tumor xenograft progression was not changed in the control group. Strong nonspecific lymphocyte proliferation response was induced. FACS also showed that the ratio of CD8+T cells in the experimental group was higher than the controls, but the serum HBcAb in experimental group was similar to the control.CONCLUSION: HBcAg can be used as an immunocarrier of vaccine, the fusion of HBcAg-T protein could induce stronger cellular immune responses and it might be a candidate for therapeutic vaccines specific for HCV.

  12. Oral delivery of probiotic expressing M cell homing peptide conjugated BmpB vaccine encapsulated into alginate/chitosan/alginate microcapsules.

    Science.gov (United States)

    Jiang, Tao; Singh, Bijay; Maharjan, Sushila; Li, Hui-Shan; Kang, Sang-Kee; Bok, Jin-Duck; Cho, Chong-Su; Choi, Yun-Jaie

    2014-11-01

    Oral administration of live probiotics as antigen delivery vectors is a promising approach in vaccine development. However, the low survival of probiotics in the gastrointestinal tract limits this approach. Therefore, the aim of this study was the encapsulation of probiotic expressing vaccine into alginate/chitosan/alginate (ACA) microcapsules (MCs) for efficient oral vaccine delivery. Here, recombinant Lactobacillus plantarum 25 (LP25) expressing M cell homing peptide fused BmpB protein was used as a model probiotic. The viability of LP25 in ACA MCs was more than 65% in simulated gastric fluid (SGF, pH 2.0) and 75% in simulated small intestinal fluid (SIF, pH 7.2) up to 2h. Encapsulated LP25 was completely released from ACA MCs in SIF within 12h. When stored at room temperature (RT) or 4°C, the viability of LP25 in ACA MCs was higher than free LP25. Interestingly, the viability of LP25 in ACA MCs at 4°C for 5weeks was above 58%, whereas viability of free LP25 stored at RT up to 5weeks was zero. After 4weeks from the first immunization, LP25-M-BmpB-loaded ACA MCs induced a stronger BmpB-specific IgG and IgA production in mice. Collectively, these findings suggest that encapsulation of probiotic by ACA MCs is a promising delivery system for oral administration of probiotic expressing vaccine.

  13. Regaining tolerance to a self-antigen by the modified vaccination technique.

    Science.gov (United States)

    Barabas, Arpad Zsigmond; Cole, Chad Douglas; Lafreniere, Rene; Weir, Donald Mackay

    2013-10-01

    Autoimmune diseases are initiated and maintained by complex immunopathological processes in environmental and genetic factor predisposed patients. In certain autoimmune diseases, the etiologies and pathogenesis of the conditions are quite well understood; yet in others, controversy surrounds as to why and how auto-injurious processes start. Clinical and laboratory examinations reasonably well define the state of progression/remission of an autoimmune disease and allow treatment according to observed findings. However, none of the presently employed treatment options are specific. In fact, they are all nonspecific in their actions and have undesirable side effects. Over the years, experiments carried out in animals have shed light on the complex immunopathological processes which contribute to disease development and progression. At least one experimental autoimmune kidney disease-which we shall describe-helps to understand how pathogenic autoimmune responses can be terminated specifically, without side effects. Since the new vaccination method-that we call modified vaccination technique-was successfully implemented in an experimental autoimmune disease model called slowly progressive Heymann nephritis for the termination of pathogenic immune responses by a target antigen-specific treatment modality, we shall highlight its use in providing insight to physicians and autoimmunologists for its future implementation in human autoimmune diseases. PMID:23296949

  14. Development of multiple sclerosis after vaccination against hepatitis B: a study based on human leucocyte antigen haplotypes.

    Science.gov (United States)

    Ozakbas, S; Idiman, E; Yulug, B; Pakoz, B; Bahar, H; Gulay, Z

    2006-09-01

    The aetiology of multiple sclerosis (MS) is still not fully understood. Infectious agents are believed to play a role in the development of this multifactorial disease. Cases in which this disease occurs after administration of both plasma-derived and recombinant hepatitis B vaccines have been reported. In this study, we compared a group of 11 MS patients who developed first clinical symptoms after hepatitis B vaccination (group I) with 71 MS patients who were never vaccinated against hepatitis B and were negative for hepatitis B serology (group II), and 20 healthy controls (group III). Mean age was 27.75 years (19-39) in group I, 30.16 years (18-50) in group II, and 34.4 years (18-50) in group III. Mean attack rate after 2 years was 1.5 in group I and 1.63 in group II. Mean Expanded Disability Status Scale score after 2 years was 1.31 in group I and 1.89 in group II. Human leucocyte antigen (HLA) typing and serology for hepatitis B surface antigen were performed in all groups. In groups I and II, HLA-DR2 was more frequent than in normal healthy subjects. This reflects the general role of HLA in the pathogenesis of MS but suggests that antigen presentation by different HLA is not involved in the development of MS after hepatitis B vaccination. Since there was no difference in the clinical features between vaccinated and nonvaccinated MS patients, this study supports recent reports that hepatitis B vaccination is safe in MS patients and that hepatitis B vaccination is not involved in the development of MS. PMID:16948644

  15. Immunostimulating complexes incorporating Eimeria tenella antigens and plant saponins as effective delivery system for coccidia vaccine immunization.

    Science.gov (United States)

    Berezin, V E; Bogoyavlenskiy, A P; Tolmacheva, V P; Makhmudova, N R; Khudyakova, S S; Levandovskaya, S V; Omirtaeva, E S; Zaitceva, I A; Tustikbaeva, G B; Ermakova, O S; Aleksyuk, P G; Barfield, R C; Danforth, H D; Fetterer, R H

    2008-04-01

    Immunostimulating complexes (ISCOMs) are unique, multimolecular structures formed by encapsulating antigens, lipids, and triterpene saponins of plant origin, and are an effective delivery system for various kinds of antigens. The uses of ISCOMs formulated with saponins from plants collected in Kazakhstan, with antigens from the poultry coccidian parasite Eimeria tenella, were evaluated for their potential use in developing a vaccine for control of avian coccidiosis. Saponins isolated from the plants Aesculus hippocastanum and Glycyrrhiza glabra were partially purified by HPLC. The saponin fractions obtained from HPLC were evaluated for toxicity in chickens and chicken embryos. The HPLC saponin fractions with the least toxicity, compared to a commercial saponin Quil A, were used to assemble ISCOMs. When chicks were immunized with ISCOMs prepared with saponins from Kazakhstan plants and E. tenella antigens, and then challenged with E. tenella oocysts, significant protection was conveyed compared to immunization with antigen alone. The results of this study indicate that ISCOMs formulated with saponins isolated from plants indigenous to Kazakhstan are an effective antigen delivery system which may be successfully used, with low toxicity, for preparation of highly immunogenic coccidia vaccine. PMID:18564738

  16. Classification of human leukocyte antigen (HLA) supertypes

    DEFF Research Database (Denmark)

    Wang, Mingjun; Claesson, Mogens H

    2014-01-01

    Identification of new antigenic peptides, derived from infectious agents or cancer cells, which bind to human leukocyte antigen (HLA) class I and II molecules, is of importance for the development of new effective vaccines capable of activating the cellular arm of the immune response. However, the...... barrier to the development of peptide-based vaccines with maximum population coverage is that the restricting HLA genes are extremely polymorphic resulting in a vast diversity of peptide-binding HLA specificities and a low population coverage for any given peptide-HLA specificity. One way to reduce this...... complexity is to group thousands of different HLA molecules into several so-called HLA supertypes: a classification that refers to a group of HLA alleles with largely overlapping peptide binding specificities. In this chapter, we focus on the state-of-the-art classification of HLA supertypes including HLA...

  17. Vaccines for allergy.

    Science.gov (United States)

    Linhart, Birgit; Valenta, Rudolf

    2012-06-01

    Vaccines aim to establish or strengthen immune responses but are also effective for the treatment of allergy. The latter is surprising because allergy represents a hyper-immune response based on immunoglobulin E production against harmless environmental antigens, i.e., allergens. Nevertheless, vaccination with allergens, termed allergen-specific immunotherapy is the only disease-modifying therapy of allergy with long-lasting effects. New forms of allergy diagnosis and allergy vaccines based on recombinant allergen-derivatives, peptides and allergen genes have emerged through molecular allergen characterization. The molecular allergy vaccines allow sophisticated targeting of the immune system and may eliminate side effects which so far have limited the use of traditional allergen extract-based vaccines. Successful clinical trials performed with the new vaccines indicate that broad allergy vaccination is on the horizon and may help to control the allergy pandemic.

  18. The characteristics exosporium antigens from different vaccine strains of bacillus antracis

    International Nuclear Information System (INIS)

    To develop of both test-systems for rapid detection and identification of B. anthracis spores and a new subunit vaccine the antigens on the spore surface should be characterized. Exosporium consists of two layers-basal and peripheral and has been form by protein, amino- and neutral polysaccharides, lipids and ash. Number of anthrax exosporium proteins was described and identified: glycoprotein BclA, BclB, alanine racemase, inosine hydrolase, glycosyl hydrolase, superoxid dismutase, ExsF, ExsY, ExsK,CotB,CotY and SoaA. So far no glycosylated proteins other then highly immunogenic glycoproteins BclA, BclB were detected in the B. anthracis spore extract although several exosporium-specific glycoprotein have been described in other members of the B.cereus family- B. thuringiensis and B. cereus. Although EA1 protein originally described as main component of S-layer from vegetative cells he can regular observed in different exosporium preparations and additionally some anti- EA1 monoclonal antibodies able to recognize spore surface. We have revealed that EA1 isolated from spore of Russians strain STI-1contain carbohydrate which determine immunogenicity of this antigen. Because some time ago we have found that exosporium protein's pattern variable among B. anthracis strains we investigated exosporium from spore of different strains of B. anthracis including STI-1, Ames, Stern and others. We have comparative characterized antigens by using Western Blotting, Two-Dimensional electrophoresis and Mass Spec analysis. The results of analysis will be presented and discussed.(author)

  19. Effect of different hapten-carrier conjugation ratios and molecular orientations on antibody affinity against a peptide antigen

    DEFF Research Database (Denmark)

    Pedersen, M. K.; Sørensen, Nanna Skall; Heegaard, Peter M. H.;

    2006-01-01

    -based assay systems and in deciding whether a vaccine-induced antibody response will be protective. With ovalbumin as a carrier protein and a peptide (7.2NY) representing a 19 ammo acid sequence from the E. coli-derived Verotoxin 2e as a model hapten we investigated whether it was possible to influence...... the affinity and titre of antibodies raised against the hapten using different conjugation ratios and orientations. The peptide was coupled to ovalbumin in four Conjugation ratios and two molecular orientations - terminal and central - and the Conjugates were verified by mass spectrometry. Mice were immunised......, the molecular orientation of the Coupled peptide has a major effect on the anti-peptide antibody titres induced....

  20. Combinatorial Synthetic Peptide Vaccine Strategy Protects against Hypervirulent CovR/S Mutant Streptococci.

    Science.gov (United States)

    Pandey, Manisha; Mortensen, Rasmus; Calcutt, Ainslie; Powell, Jessica; Batzloff, Michael R; Dietrich, Jes; Good, Michael F

    2016-04-15

    Cluster of virulence responder/sensor (CovR/S) mutant group A streptococci (GAS) are serious human pathogens of multiple M protein strains that upregulate expression of virulence factors, including the IL-8 proteaseStreptococcus pyogenescell envelope proteinase (SpyCEP), thus blunting neutrophil-mediated killing and enabling ingress of bacteria from a superficial wound to deep tissue. We previously showed that a combination vaccine incorporating J8-DT (conserved peptide vaccine from the M protein) and a recombinant SpyCEP fragment protects against CovR/S mutants. To enhance the vaccine's safety profile, we identified a minimal epitope (S2) that was the target for anti-SpyCEP Abs that could protect IL-8 from SpyCEP-mediated proteolysis. Abs from healthy humans and from mice experimentally infected with GAS also recognized S2, albeit at low titers. Native SpyCEP may be poorly immunogenic (cryptic or subdominant), and it would be to the organism's advantage if the host did not induce a strong Ab response against it. However, S2 conjugated to diphtheria toxoid is highly immunogenic and induces Abs that recognize and neutralize SpyCEP. Hence, we describe a two-component peptide vaccine that induces Abs (anti-S2) that protect IL-8 from proteolysis and other Abs (anti-J8) that cause strain-independent killing in the presence of neutrophils. We show that either component alone is ineffectual in preventing skin infection and bacteremia due to CovR/S mutants but that the combination induces complete protection. This protection correlated with a significant influx of neutrophils to the infection site. The data strongly suggest that the lack of natural immunity to hypervirulent GAS strains in humans could be rectified by this combination vaccine.

  1. Defining antigen-specific plasmablast and memory B cell subsets in human blood after viral infection or vaccination.

    Science.gov (United States)

    Ellebedy, Ali H; Jackson, Katherine J L; Kissick, Haydn T; Nakaya, Helder I; Davis, Carl W; Roskin, Krishna M; McElroy, Anita K; Oshansky, Christine M; Elbein, Rivka; Thomas, Shine; Lyon, George M; Spiropoulou, Christina F; Mehta, Aneesh K; Thomas, Paul G; Boyd, Scott D; Ahmed, Rafi

    2016-10-01

    Antigen-specific B cells bifurcate into antibody-secreting cells (ASCs) and memory B cells (MBCs) after infection or vaccination. ASCs (plasmablasts) have been extensively studied in humans, but less is known about B cells that become activated but do not differentiate into plasmablasts. Here we have defined the phenotype and transcriptional program of a subset of antigen-specific B cells, which we have called 'activated B cells' (ABCs), that were distinct from ASCs and were committed to the MBC lineage. We detected ABCs in humans after infection with Ebola virus or influenza virus and also after vaccination. By simultaneously analyzing antigen-specific ASCs and ABCs in human blood after vaccination against influenza virus, we investigated the clonal overlap and extent of somatic hypermutation (SHM) in the ASC (effector) and ABC (memory) lineages. Longitudinal tracking of vaccination-induced hemagglutinin (HA)-specific clones revealed no overall increase in SHM over time, which suggested that repeated annual immunization might have limitations in enhancing the quality of influenza-virus-specific antibody. PMID:27525369

  2. Removing N-terminal sequences in pre-S1 domain enhanced antibody and B-cell responses by an HBV large surface antigen DNA vaccine.

    Science.gov (United States)

    Ge, Guohong; Wang, Shixia; Han, Yaping; Zhang, Chunhua; Lu, Shan; Huang, Zuhu

    2012-01-01

    Although the use of recombinant hepatitis B virus surface (HBsAg) protein vaccine has successfully reduced global hepatitis B infection, there are still a number of vaccine recipients who do not develop detectable antibody responses. Various novel vaccination approaches, including DNA vaccines, have been used to further improve the coverage of vaccine protection. Our previous studies demonstrated that HBsAg-based DNA vaccines could induce both humoral and CMI responses in experimental animal models. However, one form of the the HBsAg antigen, the large S antigen (HBs-L), expressed by DNA vaccine, was not sufficiently immunogenic in eliciting antibody responses. In the current study, we produced a modified large S antigen DNA vaccine, HBs-L(T), which has a truncated N-terminal sequence in the pre-S1 region. Compared to the original HBs-L DNA vaccine, the HBs-L(T) DNA vaccine improved secretion in cultured mammalian cells and generated significantly enhanced HBsAg-specific antibody and B cell responses. Furthermore, this improved HBsL DNA vaccine, along with other HBsAg-expressing DNA vaccines, was able to maintain predominantly Th1 type antibody responses while recombinant HBsAg protein vaccines produced in either yeast or CHO cells elicited mostly Th2 type antibody responses. Our data indicate that HBsAg DNA vaccines with improved immunogenicity offer a useful alternative choice to recombinant protein-based HBV vaccines, particularly for therapeutic purposes against chronic hepatitis infection where immune tolerance led to poor antibody responses to S antigens. PMID:22844502

  3. Removing N-terminal sequences in pre-S1 domain enhanced antibody and B-cell responses by an HBV large surface antigen DNA vaccine.

    Directory of Open Access Journals (Sweden)

    Guohong Ge

    Full Text Available Although the use of recombinant hepatitis B virus surface (HBsAg protein vaccine has successfully reduced global hepatitis B infection, there are still a number of vaccine recipients who do not develop detectable antibody responses. Various novel vaccination approaches, including DNA vaccines, have been used to further improve the coverage of vaccine protection. Our previous studies demonstrated that HBsAg-based DNA vaccines could induce both humoral and CMI responses in experimental animal models. However, one form of the the HBsAg antigen, the large S antigen (HBs-L, expressed by DNA vaccine, was not sufficiently immunogenic in eliciting antibody responses. In the current study, we produced a modified large S antigen DNA vaccine, HBs-L(T, which has a truncated N-terminal sequence in the pre-S1 region. Compared to the original HBs-L DNA vaccine, the HBs-L(T DNA vaccine improved secretion in cultured mammalian cells and generated significantly enhanced HBsAg-specific antibody and B cell responses. Furthermore, this improved HBsL DNA vaccine, along with other HBsAg-expressing DNA vaccines, was able to maintain predominantly Th1 type antibody responses while recombinant HBsAg protein vaccines produced in either yeast or CHO cells elicited mostly Th2 type antibody responses. Our data indicate that HBsAg DNA vaccines with improved immunogenicity offer a useful alternative choice to recombinant protein-based HBV vaccines, particularly for therapeutic purposes against chronic hepatitis infection where immune tolerance led to poor antibody responses to S antigens.

  4. Whole tumor antigen vaccination using dendritic cells: Comparison of RNA electroporation and pulsing with UV-irradiated tumor cells

    Directory of Open Access Journals (Sweden)

    Benencia Fabian

    2008-04-01

    Full Text Available Abstract Because of the lack of full characterization of tumor associated antigens for solid tumors, whole antigen use is a convenient approach to tumor vaccination. Tumor RNA and apoptotic tumor cells have been used as a source of whole tumor antigen to prepare dendritic cell (DC based tumor vaccines, but their efficacy has not been directly compared. Here we compare directly RNA electroporation and pulsing of DCs with whole tumor cells killed by ultraviolet (UV B radiation using a convenient tumor model expressing human papilloma virus (HPV E6 and E7 oncogenes. Although both approaches led to DCs presenting tumor antigen, electroporation with tumor cell total RNA induced a significantly higher frequency of tumor-reactive IFN-gamma secreting T cells, and E7-specific CD8+ lymphocytes compared to pulsing with UV-irradiated tumor cells. DCs electroporated with tumor cell RNA induced a larger tumor infiltration by T cells and produced a significantly stronger delay in tumor growth compared to DCs pulsed with UV-irradiated tumor cells. We conclude that electroporation with whole tumor cell RNA and pulsing with UV-irradiated tumor cells are both effective in eliciting antitumor immune response, but RNA electroporation results in more potent tumor vaccination under the examined experimental conditions.

  5. Suppression of humoral immune response to hepatitis B surface antigen vaccine in BALB/c mice by 1-methyl-tryptophan co-administration

    OpenAIRE

    Sparopoulou, T; Eleftheriadis, T; Antoniadi, G; Liakopoulos, V; Stefanidis, I.; Galaktidou, G

    2011-01-01

      Background and the purpose of the study:Indoleamine 2,3-dioxygenase (IDO) suppresses adaptive immune response. The purpose of this study was to determine the effect of the IDO inhibitor namely 1-methyl-DL-tryptophan (DL-1-MT) on antibody production after vaccination with hepatitis B surface (HBs) antigen. Methods:Four groups of BALB/c mice were immunized with a HBs antigen vaccine. In the first group the vaccine had no DL-1-MT, whereas in the other three groups the vaccine containe...

  6. Recent advances in vaccine delivery.

    Science.gov (United States)

    Cordeiro, Ana S; Alonso, María J

    2016-01-01

    The field of vaccination is moving from the use of attenuated or inactivated pathogens to safer but less immunogenic protein and peptide antigens, which require stronger adjuvant compositions. Antigen delivery carriers appear to play an important role in vaccine development, providing not only antigen protection and controlled release but also an intrinsic adjuvant potential. Among them, carriers based on polymers and lipids are the most representative ones. Patent applications in this area have disclosed, either the design and preparation methods for new biocompatible antigen delivery systems or the application of the previously developed systems for the delivery of novel antigens. Some of them have also reported the use of these technologies for modern therapeutic vaccination approaches. PMID:26667309

  7. A Francisella tularensis Live Vaccine Strain That Improves Stimulation of Antigen-Presenting Cells Does Not Enhance Vaccine Efficacy

    OpenAIRE

    Schmitt, Deanna M; Dawn M O'Dee; Joseph Horzempa; Paul E Carlson; Russo, Brian C.; Bales, Jacqueline M.; Brown, Matthew J.; Nau, Gerard J.

    2012-01-01

    Vaccination is a proven strategy to mitigate morbidity and mortality of infectious diseases. The methodology of identifying and testing new vaccine candidates could be improved with rational design and in vitro testing prior to animal experimentation. The tularemia vaccine, Francisella tularensis live vaccine strain (LVS), does not elicit complete protection against lethal challenge with a virulent type A Francisella strain. One factor that may contribute to this poor performance is limited s...

  8. Immunogenicity of three recombinant hepatitis B vaccines administered to students in three doses containing half the antigen amount routinely used for adult vaccination

    Directory of Open Access Journals (Sweden)

    Baldy José Luís da Silveira

    2004-01-01

    Full Text Available We evaluated the immunogenicity of three recombinant hepatitis B vaccines, one Brazilian (Butang, Instituto Butantan and two Korean vaccines (Euvax-B, LG Chemical Ltd. and Hepavax-Gene, Greencross Vaccine Corp., administered intramuscularly to students aged 17 to 19 years in three 10-µg doses (corresponding to half the amount of antigen routinely used for adult vaccination at intervals of one month between the first and second dose, and of four months between the second and third dose. A total of 316 students non-reactive for any serological marker of hepatitis B virus infection were vaccinated: 77 (24.4% with the Butang vaccine, 71 (22.5% with Euvax-B, 85 (26.9% with Hepavax-Gene and, for comparison, 83 (26.2% with Engerix-B (GlaxoSmithKline, whose efficacy in young adults at the dose used here has been confirmed in previous studies. Similar seroconversion rates (anti-HBs > 10 mIU/mL about one month after application of the third dose were obtained for the Butang, Euvax-B, Hepavax-Gene and Engerix-B vaccines (96.2%, 98.6%, 96.5% and 97.6%, respectively. The frequency of good responders (anti-HBs > 100 mIU/mL was also similar among students receiving the four vaccines (85.8%, 91.6%, 89.4% and 89.2%, respectively. The geometric mean titers (GMT of anti-HBs about one month after the third dose obtained with these vaccines were 727.78 ± 6.46 mIU/mL, 2009.09 ± 7.16 mIU/mL, 1729.82 ± 8.85 mIU/mL and 2070.14 ± 11.69 mIU/mL, respectively. The GMT of anti-HBs induced by the Euvax-B and Engerix-B vaccines were higher than those obtained with the Butang vaccine (p < 0.05; this difference was not significant when comparing the other vaccines two-by-two. No spontaneous adverse effects attributable to the application of any dose of the four vaccines were reported.

  9. Screening of human tumor antigens for CD4 T cell epitopes by combination of HLA-transgenic mice, recombinant adenovirus and antigen peptide libraries.

    Directory of Open Access Journals (Sweden)

    Wolfram Osen

    Full Text Available BACKGROUND: As tumor antigen-specific CD4+ T cells can mediate strong therapeutic anti-tumor responses in melanoma patients we set out to establish a comprehensive screening strategy for the identification of tumor-specific CD4+ T cell epitopes suitable for detection, isolation and expansion of tumor-reactive T cells from patients. METHODS AND FINDINGS: To scan the human melanoma differentiation antigens TRP-1 and TRP-2 for HLA-DRB1*0301-restricted CD4+ T cell epitopes we applied the following methodology: Splenocytes of HLA-DRB1*0301-transgenic mice immunized with recombinant adenovirus encoding TRP-1 (Ad5.TRP-1 or TRP-2 (Ad5.TRP-2 were tested for their T cell reactivity against combinatorial TRP-1- and TRP-2-specific peptide libraries. CD4+ T cell epitopes thus identified were validated in the human system by stimulation of peripheral blood mononuclear cells (PBMC from healthy donors and melanoma patients. Using this strategy we observed that recombinant Ad5 induced strong CD4+ T cell responses against the heterologous tumor antigens. In Ad5.TRP-2-immunized mice CD4+ T cell reactivity was detected against the known HLA-DRB1*0301-restricted TRP-2(60-74 epitope and against the new epitope TRP-2(149-163. Importantly, human T cells specifically recognizing target cells loaded with the TRP-2(149-163-containing library peptide or infected with Ad5.TRP-2 were obtained from healthy individuals, and short term in vitro stimulation of PBMC revealed the presence of epitope-reactive CD4+ T cells in melanoma patients. Similarly, immunization of mice with Ad5.TRP-1 induced CD4+ T cell responses against TRP-1-derived peptides that turned out to be recognized also by human T cells, resulting in the identification of TRP-1(284-298 as a new HLA-DRB1*0301-restricted CD4+ T cell epitope. CONCLUSIONS: Our screening approach identified new HLA-DRB1*0301-restricted CD4+ T cell epitopes derived from melanoma antigens. This strategy is generally applicable to target

  10. Dengue encephalitis-associated immunopathology in the mouse model: Implications for vaccine developers and antigens inducer of cellular immune response.

    Science.gov (United States)

    Marcos, Ernesto; Lazo, Laura; Gil, Lázaro; Izquierdo, Alienys; Suzarte, Edith; Valdés, Iris; Blanco, Aracelys; Ancizar, Julio; Alba, José Suárez; Pérez, Yusleydis de la C; Cobas, Karen; Romero, Yaremis; Guillén, Gerardo; Guzmán, María G; Hermida, Lisset

    2016-08-01

    Despite the many efforts made by the scientific community in the development of vaccine candidates against dengue virus (DENV), no vaccine has been licensed up to date. Although the immunopathogenesis associated to the disease is a key factor to take into account by vaccine developers, the lack of animal models that reproduce the clinical signs of the disease has hampered the vaccine progress. Non-human primates support viral replication, but they are very expensive and do not show signs of disease. Immunocompromised mice develop viremia and some signs of the disease; however, they are not valuable for vaccine testing. Nowadays, immunocompetent mice are the most used model to evaluate the immunogenicity of vaccine candidates. These animals are resistant to DENV infection; therefore, the intracranial inoculation with neuroadapted virus, which provokes viral encephalitis, represents an alternative to evaluate the protective capacity of vaccine candidates. Previous results have demonstrated the crucial role of cellular immune response in the protection induced by the virus and vaccine candidates in this mouse encephalitis model. However, in the present work we are proposing that the magnitude of the cell-mediated immunity and the inflammatory response generated by the vaccine can modulate the survival rate after viral challenge. We observed that the intracranial challenge of naïve mice with DENV-2 induces the recruitment of immune cells that contribute to the reduction of viral load, but does not increase the survival rate. On the contrary, animals treated with cyclophosphamide, an immunosuppressive drug that affects proliferating lymphocytes, had a higher viral load but a better survival rate than untreated animals. These results suggest that the immune system is playing an immunopathogenic role in this model and the survival rate may not be a suitable endpoint in the evaluation of vaccine candidates based on antigens that induce a strong cellular immune response

  11. Hepatitis B Vaccination Coverage and Prevalence of Hepatitis B Surface Antigen Among Children in French Polynesia, 2014.

    Science.gov (United States)

    Patel, Minal K; Le Calvez, Evelyne; Wannemuehler, Kathleen; Ségalin, Jean-Marc

    2016-06-01

    French Polynesia is considered to be moderately endemic for chronic hepatitis B virus infection, with an estimated 3% of the population having hepatitis B surface antigen (HBsAg). From 1990 to 1992, a 3-dose hepatitis B vaccination series was introduced into the routine infant immunization schedule in French Polynesia, including a birth dose (BD). In 2014, a nationally representative 2-stage cluster survey was undertaken to evaluate the impact of the vaccination program on HBsAg prevalence among school children (∼6 years of age) in Cours Préparatoire (CP). Documented vaccination data were reviewed for all eligible children; children with consent were tested for HBsAg with a rapid point-of-care test. In total, 1,660 students were identified; 1,567 (94%) had vaccination data for review and 1,196 (72%) participated in the serosurvey. Three-dose vaccination coverage was 98%, while timely BD coverage, defined as a dose administered within 24 hours of life, was 89%. Receipt of the second and third doses was often delayed, with 75% and 55% receiving a second and third dose within 1 month of the recommended age, respectively. No children tested positive for HBsAg. French Polynesia's vaccination program has achieved high coverage and an HBsAg seroprevalence of 0% (0-0.5%) among CP school children, but timeliness of vaccination could be improved.

  12. Hepatitis B Vaccination Coverage and Prevalence of Hepatitis B Surface Antigen Among Children in French Polynesia, 2014.

    Science.gov (United States)

    Patel, Minal K; Le Calvez, Evelyne; Wannemuehler, Kathleen; Ségalin, Jean-Marc

    2016-06-01

    French Polynesia is considered to be moderately endemic for chronic hepatitis B virus infection, with an estimated 3% of the population having hepatitis B surface antigen (HBsAg). From 1990 to 1992, a 3-dose hepatitis B vaccination series was introduced into the routine infant immunization schedule in French Polynesia, including a birth dose (BD). In 2014, a nationally representative 2-stage cluster survey was undertaken to evaluate the impact of the vaccination program on HBsAg prevalence among school children (∼6 years of age) in Cours Préparatoire (CP). Documented vaccination data were reviewed for all eligible children; children with consent were tested for HBsAg with a rapid point-of-care test. In total, 1,660 students were identified; 1,567 (94%) had vaccination data for review and 1,196 (72%) participated in the serosurvey. Three-dose vaccination coverage was 98%, while timely BD coverage, defined as a dose administered within 24 hours of life, was 89%. Receipt of the second and third doses was often delayed, with 75% and 55% receiving a second and third dose within 1 month of the recommended age, respectively. No children tested positive for HBsAg. French Polynesia's vaccination program has achieved high coverage and an HBsAg seroprevalence of 0% (0-0.5%) among CP school children, but timeliness of vaccination could be improved. PMID:27001757

  13. Human Leukocyte Antigen (HLA) Peptides Derived from Tumor Antigens Induced by Inhibition of DNA Methylation for Development of Drug-facilitated Immunotherapy.

    Science.gov (United States)

    Shraibman, Bracha; Kadosh, Dganit Melamed; Barnea, Eilon; Admon, Arie

    2016-09-01

    Treatment of cancer cells with anticancer drugs often fails to achieve complete remission. Yet, such drug treatments may induce alteration in the tumor's gene expression patterns, including those of Cancer/Testis Antigens (CTA). The degradation products of such antigens can be presented as HLA peptides on the surface of the tumor cells and be developed into anticancer immunotherapeutics. For example, the DNA methyl transferase inhibitor, 5-aza-2'-deoxycytidine (Decitabine) has limited antitumor efficacy, yet it induces the expression of many genes, including CTAs that are normally silenced in the healthy adult tissues. In this study, the presentation of many new HLA peptides derived from CTAs and induced by Decitabine was demonstrated in three human Glioblastoma cell lines. Such presentation of CTA-derived HLA peptides can be exploited for development of new treatment modalities, combining drug treatment with anti-CTA targeted immunotherapy. The Decitabine-induced HLA peptidomes include many CTAs that are not normally detected in healthy tissues or in cancer cells, unless treated with the drug. In addition, the study included large-scale analyses of the simultaneous effects of Decitabine on the transcriptomes, proteomes and HLA peptidomes of the human Glioblastoma cells. It demonstrates the poor correlations between these three levels of gene expression, both in their total levels and in their response to the drug. The proteomics and HLA peptidomics data are available via ProteomeXchange with identifier PXD003790 and the transcriptomics data are available via GEO with identifier GSE80137.

  14. Immune responses induced by a Leishmania (Leishmania) amazonensis recombinant antigen in mice and lymphocytes from vaccinated subjects

    OpenAIRE

    Fernandes, Ana Paula; Elizabeth Cortez HERRERA; Wilson MAYRINK; Gazzinelli, Ricardo T.; LIU Wen Yu; Carlos Alberto da COSTA; Tavares, Carlos Alberto Pereira; Melo, Maria Norma; Michalick, Marilene Susan Marques; Gentz, Reiner; NASCIMENTO Evaldo

    1997-01-01

    In the search for Leishmania recombinant antigens that can be used as a vaccine against American Cutaneous Leishmaniasis, we identified a Leishmania (Leishmania) amazonensis recombinant protein of 33 kD (Larp33) which is recognized by antibodies and peripheral blood leukocytes (PBL) from subjects vaccinated with Leishvacin ®, Larp33 was expressed in Escherichia coli after cloning of a 2,2 kb Sau3A digested genomic fragment of L. (L.) amazonensis into the pDS56-6 His vector. Immunoblotting ana...

  15. Preparation and Identification of HLA-A*1101 Tetramer Loading with Human Cytomegalovirus pp65 Antigen Peptide

    Institute of Scientific and Technical Information of China (English)

    Fengyao Li; Lihui Xu; Qingbing Zha; Xiaoyun Chi; Qiantao Jia; Xianhui He

    2007-01-01

    MHC/peptide tetramer technology has been widely used to study antigen-specific T cells, especially for identifying virus-specific CD8+ T cells in humans. The tetramer molecule is composed of HLA heavy chain, β2-microglobulin (β2m), an antigenic peptide, and fluorescent-labeled streptavidin. To further investigate the HLA-A*1101-restricted CD8+ T cell responses against human cytomegalovirus (HCMV), we established an approach to prepare HLA-A*1101 tetramer complexed with a peptide from HCMV. The cDNA encoding HLA-A*1101 heavy chain was cloned and the prokaryotic expression vector for the ectodomain of HLA-A*1101 fused with a BirA substrate peptide (HLA-A*1101-BSP) at its carboxyl terminus was constructed. The fusion protein was highly expressed as inclusion bodies under optimized conditions in Escherichia coli. Moreover, HLA-A*1101-BSP protein was refolded in the presence of β2m and an HCMV peptide pp6516-24 (GPISGHVLK, GPI). Soluble HLA-A*1101-GPI monomer was biotinylated and purified to a purity of 95%, which was subsequently combined with streptavidin to form tetramers at a yield of > 80%. The HLA-A*1101-GPI tetramers could bind to virus-specific CD8+ T cells,suggesting soluble HLA-A*1101-GPI tetramers were biologically functional. This study provides the basis for further evaluation of HLA-A*1101-restricted CD8+ T cell responses against HCMV infection.

  16. Characterization of GD2 peptide mimotope DNA vaccines effective against spontaneous neuroblastoma metastases.

    Science.gov (United States)

    Fest, Stefan; Huebener, Nicole; Weixler, Silke; Bleeke, Matthias; Zeng, Yan; Strandsby, Anne; Volkmer-Engert, Rudolf; Landgraf, Christiane; Gaedicke, Gerhard; Riemer, Angelika B; Michalsky, Elke; Jaeger, Ines S; Preissner, Robert; Förster-Wald, Elisabeth; Jensen-Jarolim, Erika; Lode, Holger N

    2006-11-01

    Disialoganglioside GD2 is an established target for immunotherapy in neuroblastoma. We tested the hypothesis that active immunization against the glycolipid GD2 using DNA vaccines encoding for cyclic GD2-mimicking decapeptides (i.e., GD2 mimotopes) is effective against neuroblastoma. For this purpose, two GD2 peptide mimotopes (MA and MD) were selected based on docking experiments to anti-GD2 antibody ch14.18 (binding free energy: -41.23 kJ/mol for MA and -48.06 kJ/mol for MD) and Biacore analysis (K(d) = 12.3 x 10(-5) mol/L for MA and 5.3 x 10(-5) mol/L for MD), showing a higher affinity of MD over MA. These sequences were selected for DNA vaccine design based on pSecTag2-A (pSA) also including a T-cell helper epitope. GD2 mimicry was shown following transfection of CHO-1 cells with pSA-MA and pSA-MD DNA vaccines, with twice-higher signal intensity for cells expressing MD over MA. Finally, these DNA vaccines were tested for induction of tumor protective immunity in a syngeneic neuroblastoma model following oral DNA vaccine delivery with attenuated Salmonella typhimurium (SL 7207). Only mice receiving the DNA vaccines revealed a reduction of spontaneous liver metastases. The highest anti-GD2 humoral immune response and natural killer cell activation was observed in mice immunized with the pSA-MD, a finding consistent with superior calculated binding free energy, dissociation constant, and GD2 mimicry potential for GD2 mimotope MD over MA. In summary, we show that DNA immunization with pSA-MD may provide a useful strategy for active immunization against neuroblastoma.

  17. Identification of peptide sequences as a measure of Anthrax vaccine stability during storage

    OpenAIRE

    Whiting, Gail; Wheeler, Jun X.; Rijpkema, Sjoerd

    2014-01-01

    The UK anthrax vaccine is an alum precipitate of a sterile filtrate of Bacillus anthracis Sterne culture (AVP). An increase in shelf life of AVP from 3 to 5 years prompted us to investigate the in vivo potency and the antigen content of 12 batches with a shelf life of 6.4 to 9.9 years and one bulk with a shelf life of 23.8 years. All batches, except for a 9.4-year-old batch, passed the potency test. Mass spectrometry (MS) and in-gel difference 2-dimensional gel electrophoresis (DIGE) were use...

  18. sNebula, a network-based algorithm to predict binding between human leukocyte antigens and peptides

    Science.gov (United States)

    Luo, Heng; Ye, Hao; Ng, Hui Wen; Sakkiah, Sugunadevi; Mendrick, Donna L.; Hong, Huixiao

    2016-01-01

    Understanding the binding between human leukocyte antigens (HLAs) and peptides is important to understand the functioning of the immune system. Since it is time-consuming and costly to measure the binding between large numbers of HLAs and peptides, computational methods including machine learning models and network approaches have been developed to predict HLA-peptide binding. However, there are several limitations for the existing methods. We developed a network-based algorithm called sNebula to address these limitations. We curated qualitative Class I HLA-peptide binding data and demonstrated the prediction performance of sNebula on this dataset using leave-one-out cross-validation and five-fold cross-validations. This algorithm can predict not only peptides of different lengths and different types of HLAs, but also the peptides or HLAs that have no existing binding data. We believe sNebula is an effective method to predict HLA-peptide binding and thus improve our understanding of the immune system. PMID:27558848

  19. A High-avidity WT1-reactive T-Cell Receptor Mediates Recognition of Peptide and Processed Antigen but not Naturally Occurring WT1-positive Tumor Cells.

    Science.gov (United States)

    Jaigirdar, Adnan; Rosenberg, Steven A; Parkhurst, Maria

    2016-04-01

    Wilms tumor gene 1 (WT1) is an attractive target antigen for cancer immunotherapy because it is overexpressed in many hematologic malignancies and solid tumors but has limited, low-level expression in normal adult tissues. Multiple HLA class I and class II restricted epitopes have been identified in WT1, and multiple investigators are pursuing the treatment of cancer patients with WT1-based vaccines and adoptively transferred WT1-reactive T cells. Here we isolated an HLA-A*0201-restricted WT1-reactive T-cell receptor (TCR) by stimulating peripheral blood lymphocytes of healthy donors with the peptide WT1:126-134 in vitro. This TCR mediated peptide recognition down to a concentration of ∼0.1 ng/mL when pulsed onto T2 cells as well as recognition of HLA-A*0201 target cells transfected with full-length WT1 cDNA. However, it did not mediate consistent recognition of many HLA-A*0201 tumor cell lines or freshly isolated leukemia cells that endogeneously expressed WT1. We dissected this pattern of recognition further and observed that WT1:126-134 was more efficiently processed by immunoproteasomes compared with standard proteasomes. However, pretreatment of WT1 tumor cell lines with interferon gamma did not appreciably enhance recognition by our TCR. In addition, we highly overexpressed WT1 in several leukemia cell lines by electroporation with full-length WT1 cDNA. Some of these lines were still not recognized by our TCR suggesting possible antigen processing defects in some leukemias. These results suggest WT1:126-134 may not be a suitable target for T-cell based tumor immunotherapies. PMID:26938944

  20. Bm86 antigen induces a protective immune response against Boophilus microplus following DNA and protein vaccination in sheep.

    Science.gov (United States)

    De Rose, R; McKenna, R V; Cobon, G; Tennent, J; Zakrzewski, H; Gale, K; Wood, P R; Scheerlinck, J P; Willadsen, P

    1999-11-30

    Vaccination of sheep with a plasmid bearing the full length gene for the tick antigen Bm86 either alone or co-administered with plasmid carrying the ovine genes for the cytokines, granulocyte and macrophage colony stimulating factor (GM-CSF) or interleukin (IL)-1beta induced a relatively low level of protection against subsequent tick infestation. This tick damage reached statistical significance only for the groups which were vaccinated with plasmid encoding for Bm86, co-administered with plasmid encoding for ovine GM-CSF. Antibody titres measured against Bm86 were also low in all groups injected with the Bm86 DNA vaccine. Antibody production and anti-tick effect were significantly less than that achieved by two vaccinations with recombinant Bm86 protein. In all cases only a low level of antigen-specific stimulation of peripheral blood lymphocytes was recorded, as measured either by the incorporation of tritiated thymidine or the release of IFN-gamma. Injection of DNA encoding for Bm86, either alone or with co-administered cytokine genes, did however prime for a strong subsequent antibody response following a single injection of recombinant Bm86 protein in adjuvant. Antibody production nevertheless appeared to be slightly less effective than following two vaccinations with recombinant protein. The persistence of antibody following vaccination was the same regardless of the method of primary sensitization. In all cases the half-life of the antibody response was approximately 40-50 days indicating that, in contrast to results reported in mice, DNA vaccination in sheep did not result in sustained antibody production. PMID:10587297

  1. Bottlenose dolphin (Tursiops truncatus) papillomaviruses: vaccine antigen candidates and screening test development.

    Science.gov (United States)

    Rehtanz, Manuela; Bossart, Gregory D; Doescher, Bethany; Rector, Annabel; Van Ranst, Marc; Fair, Patricia A; Jenson, Alfred B; Ghim, Shin-Je

    2009-01-01

    Papillomaviruses (PVs) have been shown as being the etiologic agents of various benign and malignant tumours in many vertebrate species. In dolphins and porpoises, a high prevalence of orogenital tumours has recently been documented with at least four distinct novel species-specific PV types detected in such lesions. Therefore, we generated the immunological reagents to establish a serological screening test to determine the prevalence of PV infection in Atlantic bottlenose dolphins [(Tursiops truncatus (Tt)]. Using the baculovirus expression system, virus-like particles (VLPs) derived from the L1 proteins of two TtPV types, TtPV1 and TtPV2, were generated. Polyclonal antibodies against TtPV VLPs were produced in rabbits and their specificity for the VLPs was confirmed. Electron microscopy and enzyme-linked immunosorbent assay (ELISA) studies revealed that the generated VLPs self-assembled into particles presenting conformational immunodominant epitopes. As such, these particles are potential antigen candidates for a TtPV vaccine. Subsequently, the VLPs served as antigens in initial ELISA tests using sera from six bottlenose dolphins to investigate PV antibody presence. Three of these sera were derived from dolphins with genital tumour history and showed positive PV ELISA reactivity, while the remaining sera from lesion-free dolphins were PV antibody-negative. The results suggest that the developed screening test may serve as a potential tool for determining PV prevalence and thus for observing transmission rates in dolphin populations as the significance of PV infection in cetaceans starts to unfold. PMID:18676105

  2. Evaluation of multiple antigenic peptides based on the Chikungunya E2 protein for improved serological diagnosis of infection.

    Science.gov (United States)

    Bhatnagar, Santwana; Kumar, Pradeep; Mohan, Teena; Verma, Priyanka; Parida, M M; Hoti, S L; Rao, D N

    2015-03-01

    In recent years, Chikungunya virus (CHIKV) reemerged and numerous outbreaks were reported all over the world. After screening CHIKV-positive sera, we had already reported many dominant epitopes within the envelope E2 protein of CHIKV. In the present study, we aimed at developing a highly sensitive immunodiagnostic assay for CHIKV based on a multiple antigenic peptide (MAP) approach using selective epitopes of the E2 protein. MAPs in four different E2 peptide combinations were screened with CHIKV-positive sera. The MAPs reacted with all CHIKV-positive sera and no reactivity was seen with healthy or dengue-positive sera. Our results indicate that MAP 1 seems to be an alternate antigen to full-length protein E2 for immunodiagnosis of CHIKV infections with high sensitivity and specificity. PMID:25412351

  3. Procedure for preparing peptide-major histocompatibility complex tetramers for direct quantification of antigen-specific cytotoxic T lymphocytes

    Institute of Scientific and Technical Information of China (English)

    Xian-Hui He; Li-Hui Xu; Yi Liu

    2005-01-01

    AIM: To establish a simplified method for generating peptide-major histocompatibility complex (MHC) class I tetramers.METHODS: cDNAs encoding the extracellular domain of human lymphocyte antigen (HLA)-A*0201 heavy chain (A2) and β2-microglobulin (β2m) from total RNA extracted from leukocytes of HLA-A2+ donors were doned into separate expression vectors by reverse transcription-polymerase chain reaction. The recombinant A2 and β2m proteins were expressed in Escherichia coli strain BL21(DE3) and recovered from the inclusion body fraction. Soluble A2 proteins loaded with specific antigen peptides were refolded by dilution from the heavy chain in the presence of light chain β2m and HLA-A2-restricted peptide antigens. The refolded A2monomers were biotinylated with a commercial biotinylation enzyme (BirA) and purified by low pressure anion exchange chromatography on a Q-Sepharose (fast flow) column.The tetramers were then formed by mixing A2 monomers with streptavidin-PE in a molar ratio of 4:1. Flow cytometry was used to confirm the expected tetramer staining of CD8+ T cells.RESULTS: Recombinant genes for HLA-A*0201 heavy chain (A2) fused to a BirA substrate peptide (A2-BSP) and mature β2m from HLA-A2+ donor leukocytes were successfully doned and highly expressed in E. coli. Two soluble monomeric A2-peptide complexes were reconstituted from A2-BSP in the presence of β2m and peptides loaded with either human cytomegalovirus pp65495-503 peptide (NLVPMVATV,NLV; designated as A2-NLV) or influenza virus matrix protein Mp58-66 peptide (GILGFVFTL, GIL; designated as A2-GIL). Refolded A2-NLV or A2-GIL monomers were biotinylated and highly purified by single step anion exchange column chromatography. The tetramers were then formed by mixing the biotinylated A2-NLV or A2-GIL monomers with streptavidin-PE, leading to more than 80% multiplication as revealed by SDS-PAGE under non-reducing, unboiled conditions. Flow cytometry revealed that these tetramers could specifically

  4. Cooperation between CD4+ T Cells and Humoral Immunity Is Critical for Protection against Dengue Using a DNA Vaccine Based on the NS1 Antigen.

    Directory of Open Access Journals (Sweden)

    Antônio J S Gonçalves

    2015-12-01

    Full Text Available Dengue virus (DENV is spread through most tropical and subtropical areas of the world and represents a serious public health problem. At present, the control of dengue disease is mainly hampered by the absence of antivirals or a vaccine, which results in an estimated half worldwide population at risk of infection. The immune response against DENV is not yet fully understood and a better knowledge of it is now recognized as one of the main challenge for vaccine development. In previous studies, we reported that a DNA vaccine containing the signal peptide sequence from the human tissue plasminogen activator (t-PA fused to the DENV2 NS1 gene (pcTPANS1 induced protection against dengue in mice. In the present work, we aimed to elucidate the contribution of cellular and humoral responses elicited by this vaccine candidate for protective immunity. We observed that pcTPANS1 exerts a robust protection against dengue, inducing considerable levels of anti-NS1 antibodies and T cell responses. Passive immunization with anti-NS1 antibodies conferred partial protection in mice infected with low virus load (4 LD50, which was abrogated with the increase of viral dose (40 LD50. The pcTPANS1 also induced activation of CD4+ and CD8+ T cells. We detected production of IFN-γ and a cytotoxic activity by CD8+ T lymphocytes induced by this vaccine, although its contribution in the protection was not so evident when compared to CD4+ cells. Depletion of CD4+ cells in immunized mice completely abolished protection. Furthermore, transfer experiments revealed that animals receiving CD4+ T cells combined with anti-NS1 antiserum, both obtained from vaccinated mice, survived virus infection with survival rates not significantly different from pcTPANS1-immunized animals. Taken together, results showed that the protective immune response induced by the expression of NS1 antigen mediated by the pcTPANS1 requires a cooperation between CD4+ T cells and the humoral immunity.

  5. Characterization of vaccine antigens of meningococcal serogroup W isolates from Ghana and Burkina Faso from 2003 to 2009.

    Science.gov (United States)

    Ispasanie, Emma; Pluschke, Gerd; Hodgson, Abraham; Sie, Ali; MacLennan, Calman; Koeberling, Oliver

    2014-01-01

    Neisseria meningitidis is a major cause of bacterial meningitis and a considerable health problem in the 25 countries of the 'African Meningitis Belt' that extends from Senegal in West Africa to Ethiopia in the East. Approximately 80% of cases of meningococcal meningitis in Africa have been caused by strains belonging to capsular serogroup A. After the introduction of a serogroup A conjugate polysaccharide vaccine, MenAfriVac (™), that began in December 2010, the incidence of meningitis due to serogroup A has markedly declined in this region. Currently, serogroup W of N. meningitidis accounts for the majority of cases. Vaccines based on sub-capsular antigens, such as Generalized Modules for Membrane Antigens (GMMA), are under investigation for use in Africa. To analyse the antigenic properties of a serogroup W wave of colonisation and disease, we investigated the molecular diversity of the protein vaccine antigens PorA, Neisserial Adhesin A (NadA), Neisserial heparin-binding antigen (NHBA) and factor H binding protein (fHbp) of 31 invasive and carriage serogroup W isolates collected as part of a longitudinal study from Ghana and Burkina Faso between 2003 and 2009. We found that the isolates all expressed fHbp variant 2 ID 22 or 23, differing from each other by only one amino acid, and a single PorA subtype of P1.5,2. Of the isolates, 49% had a functional nhbA gene and 100% had the nadA allele 3, which contained the insertion sequence IS1301 in five isolates. Of the W isolates tested, 41% had high fHbp expression when compared with a reference serogroup B strain, known to be a high expresser of fHbp variant 2. Our results indicate that in this collection of serogroup W isolates, there is limited antigenic diversification over time of vaccine candidate outer membrane proteins (OMP), thus making them promising candidates for inclusion in a protein-based vaccine against meningococcal meningitis for Africa. PMID:25901274

  6. Establishment of an in vivo potency assay for the recombinant hepatit is B surface antigen in monovalent and combined vaccines

    OpenAIRE

    Mabel Izquierdo-López; Karelia Cosme-Diaz; Gerardo García-Illera; Zoe Núñez-Lamotte; Yamila Martínez- Cuéllar; Maribel Vega-Simón; Lourdes Costa-Anguiano; Marisel Quintana-Esquivel; Ileana Rosales-Torres; Omar Mosqueda-Lobaina

    2014-01-01

    In this paper the development of potency assay in animals (mice) was made, with the objective of demonstrating the immunogenic power of the recombinant Hepatitis B surface antigen in monovalent and combined vaccines, produced at the Center of Genetic Engineering and Biotechnology. The potency test is a parameter in quality control and it is also a tool to demonstrate the consistency of the production process. Parameters such as duration of the test, number of animals in the test, ...

  7. Geminiviral vectors based on bean yellow dwarf virus for production of vaccine antigens and monoclonal antibodies in plants

    OpenAIRE

    Chen, Qiang; He, Junyun; Phoolcharoen, Waranyoo; Mason, Hugh S.

    2011-01-01

    Expression of recombinant vaccine antigens and monoclonal antibodies using plant viral vectors has developed extensively during the past several years. The approach benefits from high yields of recombinant protein obtained within days after transient delivery of viral vectors to leaves of Nicotiana benthamiana, a tobacco relative. Modified viral genomes of both RNA and DNA viruses have been created. Geminiviruses such as bean yellow dwarf virus (BeYDV) have a small, single stranded DNA genome...

  8. H3N2 Mismatch of 2014-15 Northern Hemisphere Influenza Vaccines and Head-to-head Comparison between Human and Ferret Antisera derived Antigenic Maps

    Science.gov (United States)

    Xie, Hang; Wan, Xiu-Feng; Ye, Zhiping; Plant, Ewan P.; Zhao, Yangqing; Xu, Yifei; Li, Xing; Finch, Courtney; Zhao, Nan; Kawano, Toshiaki; Zoueva, Olga; Chiang, Meng-Jung; Jing, Xianghong; Lin, Zhengshi; Zhang, Anding; Zhu, Yanhong

    2015-10-01

    The poor performance of 2014-15 Northern Hemisphere (NH) influenza vaccines was attributed to mismatched H3N2 component with circulating epidemic strains. Using human serum samples collected from 2009-10, 2010-11 and 2014-15 NH influenza vaccine trials, we assessed their cross-reactive hemagglutination inhibition (HAI) antibody responses against recent H3 epidemic isolates. All three populations (children, adults, and older adults) vaccinated with the 2014-15 NH egg- or cell-based vaccine, showed >50% reduction in HAI post-vaccination geometric mean titers against epidemic H3 isolates from those against egg-grown H3 vaccine strain A/Texas/50/2012 (TX/12e). The 2014-15 NH vaccines, regardless of production type, failed to further extend HAI cross-reactivity against H3 epidemic strains from previous seasonal vaccines. Head-to-head comparison between ferret and human antisera derived antigenic maps revealed different antigenic patterns among representative egg- and cell-grown H3 viruses characterized. Molecular modeling indicated that the mutations of epidemic H3 strains were mainly located in antibody-binding sites A and B as compared with TX/12e. To improve vaccine strain selection, human serologic testing on vaccination-induced cross-reactivity need be emphasized along with virus antigenic characterization by ferret model.

  9. Development of a live attenuated antigenic marker classical swine fever vaccine

    Science.gov (United States)

    Classical Swine Fever, caused by Classical Swine Fever Virus (CSFV), is a highly contagious disease affecting swine worldwide. The two main strategies for disease control are prophylactic vaccination and non-vaccination “stamping out” policies. In a vaccination-to-live strategy, marker vaccines coul...

  10. The porcine circovirus type 1 capsid gene promoter improves antigen expression and immunogenicity in a HIV-1 plasmid vaccine

    Directory of Open Access Journals (Sweden)

    Burger Marieta

    2011-02-01

    Full Text Available Abstract Background One of the promising avenues for development of vaccines against Human immunodeficiency virus type 1 (HIV-1 and other human pathogens is the use of plasmid-based DNA vaccines. However, relatively large doses of plasmid must be injected for a relatively weak response. We investigated whether genome elements from Porcine circovirus type 1 (PCV-1, an apathogenic small ssDNA-containing virus, had useful expression-enhancing properties that could allow dose-sparing in a plasmid vaccine. Results The linearised PCV-1 genome inserted 5' of the CMV promoter in the well-characterised HIV-1 plasmid vaccine pTHgrttnC increased expression of the polyantigen up to 2-fold, and elicited 3-fold higher CTL responses in mice at 10-fold lower doses than unmodified pTHgrttnC. The PCV-1 capsid gene promoter (Pcap alone was equally effective. Enhancing activity was traced to a putative composite host transcription factor binding site and a "Conserved Late Element" transcription-enhancing sequence previously unidentified in circoviruses. Conclusions We identified a novel PCV-1 genome-derived enhancer sequence that significantly increased antigen expression from plasmids in in vitro assays, and improved immunogenicity in mice of the HIV-1 subtype C vaccine plasmid, pTHgrttnC. This should allow significant dose sparing of, or increased responses to, this and other plasmid-based vaccines. We also report investigations of the potential of other circovirus-derived sequences to be similarly used.

  11. A dual TLR agonist adjuvant enhances the immunogenicity and protective efficacy of the tuberculosis vaccine antigen ID93.

    Directory of Open Access Journals (Sweden)

    Mark T Orr

    Full Text Available With over eight million cases of tuberculosis each year there is a pressing need for the development of new vaccines against Mycobacterium tuberculosis. Subunit vaccines consisting of recombinant proteins are an attractive vaccine approach due to their inherent safety compared to attenuated live vaccines and the uniformity of manufacture. Addition of properly formulated TLR agonist-containing adjuvants to recombinant protein vaccines enhances the antigen-specific CD4(+ T cell response characterized by IFN-γ and TNF, both of which are critical for the control of TB. We have developed a clinical stage vaccine candidate consisting of a recombinant fusion protein ID93 adjuvanted with the TLR4 agonist GLA-SE. Here we examine whether ID93+GLA-SE can be improved by the addition of a second TLR agonist. Addition of CpG containing DNA to ID93+GLA-SE enhanced the magnitude of the multi-functional TH1 response against ID93 characterized by co-production of IFN-γ, TNF, and IL-2. Addition of CpG also improved the protective efficacy of ID93+GLA-SE. Finally we demonstrate that this adjuvant synergy between GLA and CpG is independent of TRIF signaling, whereas TRIF is necessary for the adjuvant activity of GLA-SE in the absence of CpG.

  12. Advance of Amyloid β Peptide Vaccines Against Alzheimer's Disease%靶向β淀粉样蛋白的阿尔茨海默病疫苗研究进展

    Institute of Scientific and Technical Information of China (English)

    徐青; 余云舟; 赵萌

    2011-01-01

    Alzheimer's disease(AD) is a progressive neurodegenerative disorder with pathological dementia and memory damage in clinic. Amyloid β peptide(Aβ) is showed to be a key antigen in immunotherapy of AD, and the Aβ vaccines against AD include Aβ peptide vaccines, DNA epitope vaccines, and virus vector vaccines, etc.Here, the advances of Aβ vaccines against AD were reviewed.%阿尔茨海默病(AD)是一种以认知功能障碍和记忆减退为主要临床特征的神经退行性疾病.目前,β淀粉样蛋白(AB)被认为是AD免疫治疗的关键靶标,其疫苗研究包括多肽疫苗、DNA表位疫苗及病毒载体疫苗等.我们简要地对近年来AD疫苗研究进展进行了综述.

  13. Peptide-conjugated hapten groups are the major antigenic determinants for trinitrophenyl-specific cytotoxic T cells.

    Science.gov (United States)

    von Bonin, A; Ortmann, B; Martin, S; Weltzien, H U

    1992-08-01

    Several trinitrophenyl (TNP)-specific mouse cytotoxic T cell (CTL) clones recognize TNP-conjugated peptides in association with class I MHC molecules ('hapten-peptide determinants'). However, cell modification with trinitrobenzene sulfonic acid (TNBS) also leads to the formation of TNP determinants covalently attached to MHC molecules ('altered self'). To determine the importance of 'peptide' versus 'altered self' determinants, we used the mutant cell line RMA-S which expresses peptide-free ('empty') Kb and Db molecules at 26 degrees C. Additionally, we stabilized Kb molecules on RMA-S cells at 37 degrees C using the Kb binding heptapeptide N53-59 derived from the vesicular stomatitis virus nucleoprotein. Lacking lysine, this peptide remains unmodified by TNBS and, therefore, only allows the formation of 'altered self' TNP determinants on occupied Kb molecules. RMA-S targets, pretreated or untreated with N53-59, upon TNBS modification were only lysed poorly or not at all by four different TNP-specific CTL. In contrast, all of these clones efficiently lysed TNBS-treated, unmutated RMA cells, and three of them strongly reacted with RMA or RMA-S cells in the presence of tryptic TNP-BSA peptides. Moreover, the clone unreactive for TNP-BSA peptides also recognized TNP self-peptides extracted from TNBS-treated syngeneic spleen cells. Taken together, these data clearly show that TNP residues linked to MHC via associated peptides but not by covalent bondage represent the dominant antigenic epitopes for class I MHC-restricted, hapten-specific T cells. PMID:1384686

  14. Phenotypic and Functional Analysis of LCMV gp33-41-Specific CD8 T Cells Elicited by Multiple Peptide Immunization in Mice Revealed the Up-regulation of PD-1 Expression on Antigen Specific CD8 T Cells

    Institute of Scientific and Technical Information of China (English)

    Yi Liu; Lihui Xu; Yiqun Jiang; Jianfang Sun; Xianhui He

    2007-01-01

    The phenotype and function of antigen-specific CD8 T cells are closely associated with the efficacy of a therapeutic vaccination. Here we showed that multiple immunizations with LCMV gp33-41 peptide (KAV) in Freund's adjuvant could induce KAV-specific CD8 T cells with low expression of CD127 and CD62L molecules. The inhibitory receptor PD-1 was also expressed on a substantial part of KAV-specific CD8 T cells, and its expression level on KAV-specific CD8 T cells in spleen and lymph nodes was much higher when compared to those in peripheral blood. Furthermore, KAV-specific CD8 T cells could specifically kill KAV-pulsed target cells in vivo but the efficiency was low. These data suggest that prime-boost vaccination schedule with peptide in Freund's adjuvant can elicit antigen-specific CD8 T cells of effector-like phenotype with partial functional exhaustion, which may only provide short-term protection against the pathogen.

  15. Allergy Vaccines Using a Mycobacterium-Secreted Antigen, Ag85B, and an IL-4 Antagonist.

    Science.gov (United States)

    Tsujimura, Yusuke; Yasutomi, Yasuhiro

    2016-01-01

    In recent decades, the prevalence of allergic diseases, including bronchial asthma, airway hypersensitivity, hay fever, and atopic dermatitis, has been increasing in the industrialized world, and effective treatments probably require manipulating the inflammatory response to pathogenic allergens. T helper (Th) 2 cells are thought to play a crucial role in the initiation, progression, and persistence of allergic responses in association with production of interleukin (IL)-4, IL-5, and IL-13. Therefore, a strategy of a shift from Th2- to Th1-type immune response may be valuable in the prophylaxis and management of allergic diseases. It is also necessary to develop prophylactic and therapeutic treatment that induces homeostatic functions in the multifaceted allergic environment, because various factors including innate and adaptive immunity, mucosal immune response, and functional and structural maintenance of local tissue might be involved in the pathogenesis of allergic disorders. We review herein recent findings related to the curative effect for mouse models of asthma and atopic dermatitis using DNA-, virus-, and protein-based vaccines of a Mycobacterium secretion antigen, Ag85B, and a plasmid encoding cDNA of antagonistic IL-4 mutant.

  16. Recombinant Varicella-Zoster Virus Vaccines as Platforms for Expression of Foreign Antigens

    Directory of Open Access Journals (Sweden)

    Wayne L. Gray

    2013-01-01

    Full Text Available Varicella-zoster virus (VZV vaccines induce immunity against childhood chickenpox and against shingles in older adults. The safety, efficacy, and widespread use of VZV vaccines suggest that they may also be effective as recombinant vaccines against other infectious diseases that affect the young and the elderly. The generation of recombinant VZV vaccines and their evaluation in animal models are reviewed. The potential advantages and limitations of recombinant VZV vaccines are addressed.

  17. Influence of serogroup B meningococcal vaccine antigens on growth and survival of the meningococcus in vitro and in ex vivo and in vivo models of infection.

    Science.gov (United States)

    Seib, Kate L; Oriente, Francesca; Adu-Bobie, Jeannette; Montanari, Paolo; Ferlicca, Francesca; Giuliani, Marzia M; Rappuoli, Rino; Pizza, Mariagrazia; Delany, Isabel

    2010-03-11

    A novel vaccine against serogroup B meningococcal disease - containing a combination of protein antigens identified by reverse vaccinology: fHBP fused to GNA2091, GNA2132 fused to GNA1030, and NadA - is currently in Phase III clinical trials. In order to determine the role of these antigens in the growth, survival and fitness of the meningococcus, we generated a mutant lacking the expression of all five protein antigens (5KO), a mutant lacking the three main antigens (fHBP, GNA2132 and NadA; 3KO), as well as strains lacking the single antigens. Our results show that abrogation of expression of these antigens in Neisseria meningitidis results in reduced growth in vitro, increased sensitivity of the bacterium to stresses it may encounter in the host, as well as reduced fitness in ex vivo models of infection and in an in vivo infant rat competitive index assay. These results support a multivalent vaccine approach, which was undertaken to strengthen the protective activity of the vaccine antigens, increase the breadth of MenB strains targeted by the vaccine, and limit the potential for selection of vaccine escape mutants.

  18. Cutting Edge: Coding Single Nucleotide Polymorphisms of Endoplasmic Reticulum Aminopeptidase 1 Can Affect Antigenic Peptide Generation In Vitro by Influencing Basic Enzymatic Properties of the Enzyme

    OpenAIRE

    Evnouchidou, Irini; Kamal, Ram P.; Seregin, Sergey S.; Goto, Yoshikuni; Tsujimoto, Masafumi; Hattori, Akira; Voulgari, Paraskevi V; Drosos, Alexandros A.; Amalfitano, Andrea; Ian A York; Stratikos, Efstratios

    2011-01-01

    ER aminopeptidase 1 (ERAP1) customizes antigenic peptide precursors for MHC class I presentation and edits the antigenic peptide repertoire. Coding single nucleotide polymorphisms (SNPs) in ERAP1 were recently linked with predisposition to autoimmune disease, suggesting a link between pathogenesis of autoimmunity and ERAP1-mediated Ag processing. To investigate this possibility, we analyzed the effect that disease-linked SNPs have on Ag processing by ERAP1 in vitro. Michaelis–Menten analysis ...

  19. Increasing a Robust Antigen-Specific Cytotoxic T Lymphocyte Response by FMDV DNA Vaccination with IL-9 Expressing Construct

    Directory of Open Access Journals (Sweden)

    Qiang Zou

    2010-01-01

    Full Text Available Various chemokines and cytokines as adjuvants can be used to improve efficacy of DNA vaccination. In this study, we sought to investigate if a DNA construct expressing IL-9 (designed as proV-IL9 as a molecular adjuvant enhance antigen specific immune responses elicited by the pcD-VP1 DNA vaccination. Mice immunized with pcD-VP1 combined with proV-IL9 developed a strong humoral response. In addition, the coinoculation induced significant higher level of antigen-specific cell proliferation and cytotoxic response. This agreed well with higher expression level of IFN-γ and perforin in CD8+ T cells, but not with IL-17 in these T cells. The results indicate that IL-9 induces the development of IFN-γ-producing CD8+ T cells (Tc1, but not the IL-17-producing CD8+ T cells (Tc17. Up-regulated expressions of BCL-2 and BCL-XL were exhibited in these Tc1 cells, suggesting that IL-9 may trigger antiapoptosis mechanism in these cells. Together, these results demonstrated that IL-9 used as molecular adjuvant could enhance the immunogenicity of DNA vaccination, in augmenting humoral and cellular responses and particularly promoting Tc1 activations. Thus, the IL-9 may be utilized as a potent Tc1 adjuvant for DNA vaccines.

  20. Sequence variations in the Boophilus microplus Bm86 locus and implications for immunoprotection in cattle vaccinated with this antigen.

    Science.gov (United States)

    García-García, J C; Gonzalez, I L; González, D M; Valdés, M; Méndez, L; Lamberti, J; D'Agostino, B; Citroni, D; Fragoso, H; Ortiz, M; Rodríguez, M; de la Fuente, J

    1999-11-01

    Cattle tick infestations constitute a major problem for the cattle industry in tropical and subtropical regions of the world. Traditional control methods have been only partially successful, hampered by the selection of chemical-resistant tick populations. The Boophilus microplus Bm86 protein was isolated from tick gut epithelial cells and shown to induce a protective response against tick infestations in vaccinated cattle. Vaccine preparations including the recombinant Bm86 are used to control cattle tick infestations in the field as an alternative measure to reduce the losses produced by this ectoparasite. The principle for the immunological control of tick infestations relies on a polyclonal antibody response against the target antigen and, therefore, should be difficult to select for tick-resistant populations. However, sequence variations in the Bm86 locus, among other factors, could affect the effectiveness of Bm86-containing vaccines. In the present study we have addressed this issue, employing data obtained with B. microplus strains from Australia, Mexico, Cuba, Argentina and Venezuela. The results showed a tendency in the inverse correlation between the efficacy of the vaccination with Bm86 and the sequence variations in the Bm86 locus (R2 = 0.7). The mutation fixation index in the Bm86 locus was calculated and shown to be between 0.02 and 0.1 amino acids per year. Possible implications of these findings for the immunoprotection of cattle against tick infestations employing the Bm86 antigen are discussed. PMID:10668863

  1. Pregnancy Vaccination with Gold Glyco-Nanoparticles Carrying Listeria monocytogenes Peptides Protects against Listeriosis and Brain- and Cutaneous-Associated Morbidities

    Directory of Open Access Journals (Sweden)

    Ricardo Calderón-Gonzalez

    2016-08-01

    Full Text Available Listeriosis is a fatal infection for fetuses and newborns with two clinical main morbidities in the neonatal period, meningitis and diffused cutaneous lesions. In this study, we vaccinated pregnant females with two gold glyconanoparticles (GNP loaded with two peptides, listeriolysin peptide 91–99 (LLO91–99 or glyceraldehyde-3-phosphate dehydrogenase 1–22 peptide (GAPDH1–22. Neonates born to vaccinated mothers were free of bacteria and healthy, while non-vaccinated mice presented clear brain affections and cutaneous diminishment of melanocytes. Therefore, these nanoparticle vaccines are effective measures to offer pregnant mothers at high risk of listeriosis interesting therapies that cross the placenta.

  2. Proinsulin multi-peptide immunotherapy induces antigen-specific regulatory T cells and limits autoimmunity in a humanized model.

    Science.gov (United States)

    Gibson, V B; Nikolic, T; Pearce, V Q; Demengeot, J; Roep, B O; Peakman, M

    2015-12-01

    Peptide immunotherapy (PIT) is a targeted therapeutic approach, involving administration of disease-associated peptides, with the aim of restoring antigen-specific immunological tolerance without generalized immunosuppression. In type 1 diabetes, proinsulin is a primary antigen targeted by the autoimmune response, and is therefore a strong candidate for exploitation via PIT in this setting. To elucidate the optimal conditions for proinsulin-based PIT and explore mechanisms of action, we developed a preclinical model of proinsulin autoimmunity in a humanized HLA-DRB1*0401 transgenic HLA-DR4 Tg mouse. Once proinsulin-specific tolerance is broken, HLA-DR4 Tg mice develop autoinflammatory responses, including proinsulin-specific T cell proliferation, interferon (IFN)-γ and autoantibody production. These are preventable and quenchable by pre- and post-induction treatment, respectively, using intradermal proinsulin-PIT injections. Intradermal proinsulin-PIT enhances proliferation of regulatory [forkhead box protein 3 (FoxP3(+))CD25(high) ] CD4 T cells, including those capable of proinsulin-specific regulation, suggesting this as its main mode of action. In contrast, peptide delivered intradermally on the surface of vitamin D3-modulated (tolerogenic) dendritic cells, controls autoimmunity in association with proinsulin-specific IL-10 production, but no change in regulatory CD4 T cells. These studies define a humanized, translational model for in vivo optimization of PIT to control autoimmunity in type 1 diabetes and indicate that dominant mechanisms of action differ according to mode of peptide delivery. PMID:26206289

  3. Prime-boost bacillus Calmette-Guérin vaccination with lentivirus-vectored and DNA-based vaccines expressing antigens Ag85B and Rv3425 improves protective efficacy against Mycobacterium tuberculosis in mice.

    Science.gov (United States)

    Xu, Ying; Yang, Enzhuo; Wang, Jianguang; Li, Rui; Li, Guanghua; Liu, Guoyuan; Song, Na; Huang, Qi; Kong, Cong; Wang, Honghai

    2014-10-01

    To prevent the global spread of tuberculosis (TB), more effective vaccines and vaccination strategies are urgently needed. As a result of the success of bacillus Calmette-Guérin (BCG) in protecting children against miliary and meningeal TB, the majority of individuals will have been vaccinated with BCG; hence, boosting BCG-primed immunity will probably be a key component of future vaccine strategies. In this study, we compared the ability of DNA-, protein- and lentiviral vector-based vaccines that express the antigens Ag85B and Rv3425 to boost the effects of BCG in the context of immunity and protection against Mycobacterium tuberculosis in C57BL/6 mice. Our results demonstrated that prime-boost BCG vaccination with a lentiviral vector expressing the antigens Ag85B and Rv3425 significantly enhanced immune responses, including T helper type 1 and CD8(+) cytotoxic T lymphocyte responses, compared with DNA- and protein-based vaccines. However, lentivirus-vectored and DNA-based vaccines greatly improved the protective efficacy of BCG against M. tuberculosis, as indicated by a lack of weight loss and significantly reduced bacterial loads and histological damage in the lung. Our study suggests that the use of lentiviral or DNA vaccines containing the antigens Ag85B and Rv3425 to boost BCG is a good choice for the rational design of an efficient vaccination strategy against TB.

  4. Comparative testing of six antigen-based malaria vaccine candidates directed toward merozoite-stage Plasmodium falciparum

    DEFF Research Database (Denmark)

    Arnot, David E; Cavanagh, David R; Remarque, Edmond J;

    2008-01-01

    Immunogenicity testing of Plasmodium falciparum antigens being considered as malaria vaccine candidates was undertaken in rabbits. The antigens compared were recombinant baculovirus MSP-1(19) and five Pichia pastoris candidates, including two versions of MSP-1(19), AMA-1 (domains I and II), AMA-1......+MSP-1(19), and fused AMA-1/MSP-1(19)). Animals were immunized with equimolar amounts of each antigen, formulated in Montanide ISA720. The specificities and titers of antibodies were compared using immunofluorescence assays and enzyme-linked immunosorbent assay (ELISA). The antiparasite activity...... of immunoglobulin G (IgG) in in vitro cultures was determined by growth inhibition assay, flow cytometry, lactate dehydrogenase assay, and microscopy. Baculovirus MSP-1(19) immunizations produced the highest parasite-specific antibody titers in immunofluorescence assays. In ELISAs, baculovirus-produced MSP-1...

  5. Antigen Processing of the Heptavalent Pneumococcal Conjugate Vaccine Carrier Protein CRM197 Differs Depending on the Serotype of the Attached Polysaccharide

    OpenAIRE

    Leonard, Ethan G.; Canaday, David H.; Harding, Clifford V.; Schreiber, John R.

    2003-01-01

    The pneumococcal (Pn) conjugate vaccine includes seven different polysaccharides (PS) conjugated to CRM197. Utilizing antigen-processing cells and a CRM197-specific mouse T-cell hybridoma, we found that the serotype of conjugated PnPS dramatically affected antigen processing of CRM197. Unconjugated CRM197 and serotype conjugates 14 and 18C were processed more efficiently.

  6. A New Gene Family (ariel) Encodes Asparagine-Rich Entamoeba histolytica Antigens, Which Resemble the Amebic Vaccine Candidate Serine-Rich E. histolytica Protein

    OpenAIRE

    Mai, Zhiming; Samuelson, John

    1998-01-01

    A family of genes, called ariel, are named for and encode asparagine-rich Entamoeba histolytica antigens containing 2 to 16 octapeptide repeats. Ariel proteins, which are constitutively expressed by trophozoites, belong to a large antigen family that includes the serine-rich E. histolytica protein (SREHP), an amebic vaccine candidate.

  7. Phase I Study of Safety and Immunogenicity of an Escherichia coli-Derived Recombinant Protective Antigen (rPA) Vaccine to Prevent Anthrax in Adults

    OpenAIRE

    Brown, Bruce K.; Josephine Cox; Anita Gillis; VanCott, Thomas C.; Mary Marovich; Mark Milazzo; Tanya Santelli Antonille; Lindsay Wieczorek; Mckee, Kelly T.; Karen Metcalfe; Mallory, Raburn M.; Deborah Birx; Polonis, Victoria R.; Merlin L Robb

    2010-01-01

    BACKGROUND: The fatal disease caused by Bacillus anthracis is preventable with a prophylactic vaccine. The currently available anthrax vaccine requires a lengthy immunization schedule, and simpler and more immunogenic options for protection against anthrax are a priority for development. In this report we describe a phase I clinical trial testing the safety and immunogenicity of an anthrax vaccine using recombinant Escherichia coli-derived, B. anthracis protective antigen (rPA). METHODOLOGY/P...

  8. Evaluation of a Salmonella vectored vaccine expressing Mycobacterium avium subsp. paratuberculosis antigens against challenge in a goat model.

    Directory of Open Access Journals (Sweden)

    Syed M Faisal

    Full Text Available Johnes disease (JD, caused by Mycobacterium avium subsp paratuberculosis (MAP, occurs worldwide as chronic granulomatous enteritis of domestic and wild ruminants. To develop a cost effective vaccine, in a previous study we constructed an attenuated Salmonella strain that expressed a fusion product made up of partial fragments of MAP antigens (Ag85A, Ag85B and SOD that imparted protection against challenge in a mouse model. In the current study we evaluated the differential immune response and protective efficacy of the Sal-Ag vaccine against challenge in a goat model as compared to the live attenuated vaccine MAP316F. PBMCs from goats vaccinated with Sal-Ag and challenged with MAP generated significantly lower levels of IFN-γ, following in vitro stimulation with either Antigen-mix or PPD jhonin, than PBMC from MAP316F vaccinated animals. Flow cytometric analysis showed the increase in IFN-γ correlated with a significantly higher level of proliferation of CD4, CD8 and γδT cells and an increased expression of CD25 and CD45R0 in MAP316F vaccinated animals as compared to control animals. Evaluation of a range of cytokines involved in Th1, Th2, Treg, and Th17 immune responses by quantitative PCR showed low levels of expression of Th1 (IFN-γ, IL-2, IL-12 and proinflammatory cytokines (IL-6, IL-8, IL-18, TNF-α in the Sal-Ag immunized group. Significant levels of Th2 and anti-inflammatory cytokines transcripts (IL-4, IL-10, IL-13, TGF-β were expressed but their level was low and with a pattern similar to the control group. Over all, Sal-Ag vaccine imparted partial protection that limited colonization in tissues of some animals upon challenge with wild type MAP but not to the level achieved with MAP316F. In conclusion, the data indicates that Sal-Ag vaccine induced only a low level of protective immunity that failed to limit the colonization of MAP in infected animals. Hence the Sal-Ag vaccine needs further refinement to increase its efficacy.

  9. Optimization of immune responses induced by therapeutic vaccination with cross-reactive antigens in a humanized hepatitis B surface antigen transgenic mouse model.

    Science.gov (United States)

    Bourgine, Maryline; Dion, Sarah; Godon, Ophélie; Guillen, Gerardo; Michel, Marie-Louise; Aguilar, Julio Cesar

    2012-08-15

    The absence of relevant animal models of chronic hepatitis B virus (HBV) infection has hampered the evaluation and development of therapeutic HBV vaccines. In this study, we generated a novel transgenic mouse lineage that expresses human class I and II HLA molecules and the hepatitis B surface antigen (HBsAg). HBsAg and hepatitis B core antigen (HBcAg) administered as plasmid DNAs and recombinant proteins, either alone or in combination, were evaluated as therapeutic vaccine candidates in this mouse model. Our results emphasize the importance of the route of administration in breaking HBsAg tolerance. Although immunizing the transgenic mice with DNA encoding homologous HBsAg was sufficient to induce CD8+ T-cell responses, HBsAg from a heterologous subtype was required to induce a CD4+ T-cell response. Importantly, only prime-boost immunization protocols that combined plasmid DNA injection followed by protein injection induced the production of antibodies against the HBsAg expressed by the transgenic mice. PMID:22591777

  10. Cationic Lipid-Formulated DNA Vaccine against Hepatitis B Virus : Immunogenicity of MIDGE-Th1 Vectors Encoding Small and Large Surface Antigen in Comparison to a Licensed Protein Vaccine

    NARCIS (Netherlands)

    Endmann, Anne; Klunder, Katharina; Kapp, Kerstin; Riede, Oliver; Oswald, Detlef; Talman, Eduard G.; Schroff, Matthias; Kleuss, Christiane; Ruiters, Marcel H. J.; Juhls, Christiane

    2014-01-01

    Currently marketed vaccines against hepatitis B virus (HBV) based on the small (S) hepatitis B surface antigen (HBsAg) fail to induce a protective immune response in about 10% of vaccinees. DNA vaccination and the inclusion of PreS1 and PreS2 domains of HBsAg have been reported to represent feasible

  11. Suppression of humoral immune response to hepatitis B surface antigen vaccine in BALB/c mice by 1-methyl-tryptophan co-administration

    Directory of Open Access Journals (Sweden)

    T Sparopoulou

    2011-07-01

    Full Text Available   Background and the purpose of the study:Indoleamine 2,3-dioxygenase (IDO suppresses adaptive immune response. The purpose of this study was to determine the effect of the IDO inhibitor namely 1-methyl-DL-tryptophan (DL-1-MT on antibody production after vaccination with hepatitis B surface (HBs antigen. Methods:Four groups of BALB/c mice were immunized with a HBs antigen vaccine. In the first group the vaccine had no DL-1-MT, whereas in the other three groups the vaccine contained 1 mg , 10 mg and 20 mg DL-1-MT. Blood samples were collected 5 weeks post-vaccination and anti-HBs antibodies in the serum were measured by ELISA. Results:Compared to the three groups of mice that were immunized with the vaccines containing DL-1-MT, serum anti-HBs level was much higher in the mice that were immunized with the vaccine with out DL-1-MT. Conclusions:Inhibition of IDO at the time of vaccination decreased humoral immune response to HBs antigen vaccine. The idea that IDO activity is simply immunosuppressive may need to be re-evaluated.

  12. ERAP1 functions override the intrinsic selection of specific antigens as immunodominant peptides, thereby altering the potency of antigen-specific cytolytic and effector memory T-cell responses.

    Science.gov (United States)

    Rastall, David P W; Aldhamen, Yasser A; Seregin, Sergey S; Godbehere, Sarah; Amalfitano, Andrea

    2014-12-01

    Endoplasmic reticulum aminopeptidase 1 (ERAP1) is a critical component of the adaptive immune system that has been shown to increase or decrease the presentation of specific peptides on MHC class I molecules. Here, we have demonstrated that ERAP1 functions are not only important during the presentation of antigen-derived peptides, but these functions can also completely change which antigen-derived peptides ultimately become selected as immunodominant T-cell epitopes. Our results suggest that ERAP1 may do this by destroying epitopes that would otherwise become immunodominant in the absence of adequate ERAP1 functionality. We further establish that ERAP1-mediated influences on T-cell functions are both qualitative and quantitative, by demonstrating that loss of ERAP1 function redirects CTL killing toward a different set of antigen-derived epitopes and increases the percent of antigen-specific memory T cells elicited by antigen exposure. As a result, our studies suggest that normal ERAP1 activity can act to suppress the numbers of T effector memory cells that respond to a given antigen. This unique finding may shed light on why certain ERAP1 single nucleotide polymorphisms are associated with several autoimmune diseases, for example, by significantly altering the robustness and quality of CD8+ T-cell memory responses to antigen-derived peptides. PMID:25087231

  13. Phase I trial of thymidylate synthase poly-epitope peptide (TSPP) vaccine in advanced cancer patients.

    Science.gov (United States)

    Cusi, Maria Grazia; Botta, Cirino; Pastina, Pierpaolo; Rossetti, Maria Grazia; Dreassi, Elena; Guidelli, Giacomo Maria; Fioravanti, Antonella; Martino, Elodia Claudia; Gandolfo, Claudia; Pagliuchi, Marco; Basile, Assunta; Carbone, Salvatore Francesco; Ricci, Veronica; Micheli, Lucia; Tassone, Pierfrancesco; Tagliaferri, Pierosandro; Pirtoli, Luigi; Correale, Pierpaolo

    2015-09-01

    Thymidylate synthase (TS) poly-epitope peptide (TSPP) is a 27-mer peptide vaccine containing the amino acidic sequences of three epitopes with HLA-A2.1-binding motifs of TS, an enzyme overexpressed in cancer cells, which plays a crucial role in DNA repair and replication. Based on the results of preclinical studies, we designed a phase Ib trial (TSPP/VAC1) to investigate, in a dose escalation setting, the safety and the biological activity of TSPP vaccination alone (arm A) or in combination with GM-CSF and IL-2 (arm B) in cancer patients. Twenty-one pretreated metastatic cancer patients, with a good performance status (ECOG ≤ 1) and no severe organ failure or immunological disease, were enrolled in the study (12 in arm A, nine in arm B) between April 2011 and January 2012, with a median follow-up of 28 months. TSPP resulted safe, and its maximal tolerated dose was not achieved. No grade 4 toxicity was observed. The most common adverse events were grade 2 dermatological reactions to the vaccine injection, cough, rhinitis, fever, poly-arthralgia, gastro-enteric symptoms and, to a lesser extent, moderate hypertension and hypothyroidism. We detected a significant rise in auto-antibodies and TS-epitope-specific CTL precursors. Furthermore, TSPP showed antitumor activity in this group of pretreated patients; indeed, we recorded one partial response and seven disease stabilizations (SD) in arm A, and three SD in arm B. Taken together, our findings provide the framework for the evaluation of the TSPP anti-tumor activity in further disease-oriented clinical trials. PMID:26031574

  14. Poly (I:C)-DOTAP cationic nanoliposome containing multi-epitope HER2-derived peptide promotes vaccine-elicited anti-tumor immunity in a murine model.

    Science.gov (United States)

    Alipour Talesh, Ghazal; Ebrahimi, Zahra; Badiee, Ali; Mansourian, Mercedeh; Attar, Hossein; Arabi, Leila; Jalali, Seyed Amir; Jaafari, Mahmoud Reza

    2016-08-01

    In the current study we aimed at developing a vaccine delivery/adjuvant system to enhance anti-tumor immunity against the natural multi-epitope HER2/Neu-derived P5 peptide. Polyriboinosinic: polyribocytidylic acid [Poly (I:C)] is a strong immunoadjuvant able to enhance specific antitumor immunity induced by peptide-based vaccines. Nevertheless, delivering the peptide and adjuvant intracellularly into their target site remains a challenging issue. We hypothesized this barrier could be overcome through the use of a cationic nanoliposome carrier system which can carry and protect the antigen and adjuvant in the extracellular environment and augment the induction of antitumor immunity. P5 was encapsulated in cationic nanoliposomes composed of 1,2-dioleoyl-3-trimethylammonium propane (DOTAP)-Cholesterol either alone or complexed with Poly (I:C). Immunocompetent BALB/c mice were immunized with the formulations 3 times in two-week intervals and the efficiency and type of immune response were then evaluated both in vitro and in vivo. The groups immunized with Lip-P5+PIC (DOTAP-Cholestrol-P5+Poly (I:C)) and Lip+PIC (DOTAP-Cholestrol+Poly (I:C)) enhanced the release of Interferon (IFN)-γ in comparison with other groups. Flow cytometry analysis revealed that Lip-P5+PIC formulation induced the highest level of IFN-γ in CD8(+) lymphocytes. Lip-P5+PIC, Lip+PIC and Lip-P5 (DOTAP-Cholestrol-P5) provided some extent of protection in terms of tumor regression in TUBO tumor mice model during the first 65days post tumor challenge but at the end only the tumors of mice immunized with Lip-P5+PIC were significantly smaller than all other groups. Furthermore, tumors of mice receiving Lip-P5+PIC grew at a significantly slower rate throughout the observation period. Our results showed that the combination of Poly (I:C) and DOTAP with the tumor antigen and without applying additional T-helper epitope induced strong antitumor responses. The observations presented here are of great interest

  15. Persistence at one year of age of antigen-induced cellular immune responses in preterm infants vaccinated against whooping cough: comparison of three different vaccines and effect of a booster dose.

    Science.gov (United States)

    Vermeulen, Françoise; Dirix, Violette; Verscheure, Virginie; Damis, Eliane; Vermeylen, Danièle; Locht, Camille; Mascart, Françoise

    2013-04-01

    Due to their high risk of developing severe Bordetella pertussis (Bp) infections, it is recommended to immunize preterm infants at their chronological age. However, little is known about the persistence of their specific immune responses, especially of the cellular responses recognized to play a role in protection. We compared here the cellular immune responses to two major antigens of Bp between three groups of one year-old children born prematurely, who received for their primary vaccination respectively the whole cell vaccine Tetracoq(®) (TC), the acellular vaccine Tetravac(®) (TV), or the acellular vaccine Infanrix-hexa(®) (IR). Whereas most children had still detectable IFN-γ responses at one year of age, they were lower in the IR-vaccinated children compared to the two other groups. In contrast, both the TV- and the IR-vaccinated children displayed higher Th2-type immune responses, resulting in higher antigen-specific IFN-γ/IL-5 ratios in TC- than in TV- or IR-vaccinated children. The IFN-γ/IL-5 ratio of mitogen-induced cytokines was also lower in IR- compared to TC- or TV-vaccinated children. No major differences in the immune responses were noted after the booster compared to the pre-booster responses for each vaccine. The IR-vaccinated children had a persistently low specific Th1-type immune response associated with high specific Th2-type immune responses, resulting in lower antigen-specific IFN-γ/IL-5 ratios compared to the two other groups. We conclude that antigen-specific cellular immune responses persisted in one year-old children born prematurely and vaccinated during infancy at their chronological age, that a booster dose did not significantly boost the cellular immune responses, and that the Th1/Th2 balance of the immune responses is modulated by the different vaccines.

  16. Improving Multi-Epitope Long Peptide Vaccine Potency by Using a Strategy that Enhances CD4+ T Help in BALB/c Mice.

    Science.gov (United States)

    Ghaffari-Nazari, Haniyeh; Tavakkol-Afshari, Jalil; Jaafari, Mahmoud Reza; Tahaghoghi-Hajghorbani, Sahar; Masoumi, Elham; Jalali, Seyed Amir

    2015-01-01

    Peptide-based vaccines are attractive approaches for cancer immunotherapy; but the success of these vaccines in clinical trials have been limited. Our goal is to improve immune responses and anti-tumor effects against a synthetic, multi-epitope, long peptide from rat Her2/neu (rHer2/neu) using the help of CD4+ T cells and appropriate adjuvant in a mouse tumor model. Female BALB/c mice were vaccinated with P5+435 multi-epitope long peptide that presents epitopes for cytotoxic T lymphocytes (CTL) in combination with a universal Pan DR epitope (PADRE) or CpG-oligodeoxynucleotides (CpG-ODNs) as a Toll-like receptor agonist adjuvant. The results show that vaccination with the multi-epitope long peptide in combination with the PADRE peptide and CpG-ODN induced expansion of subpopulations of CD4+ and CD8+ cells producing IFN-γ, the average tumor size in the vaccinated mice was less than that of the other groups, and tumor growth was inhibited in 40% of the mice in the vaccinated group. The mean survival time was 82.6 ± 1.25 days in mice vaccinated with P5+435 + CpG+ PADRE. Our results demonstrate that inclusion of PADRE and CpG with the peptide vaccine enhanced significant tumor specific-immune responses in vaccinated mice. PMID:26556756

  17. Improving Multi-Epitope Long Peptide Vaccine Potency by Using a Strategy that Enhances CD4+ T Help in BALB/c Mice.

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    Haniyeh Ghaffari-Nazari

    Full Text Available Peptide-based vaccines are attractive approaches for cancer immunotherapy; but the success of these vaccines in clinical trials have been limited. Our goal is to improve immune responses and anti-tumor effects against a synthetic, multi-epitope, long peptide from rat Her2/neu (rHer2/neu using the help of CD4+ T cells and appropriate adjuvant in a mouse tumor model. Female BALB/c mice were vaccinated with P5+435 multi-epitope long peptide that presents epitopes for cytotoxic T lymphocytes (CTL in combination with a universal Pan DR epitope (PADRE or CpG-oligodeoxynucleotides (CpG-ODNs as a Toll-like receptor agonist adjuvant. The results show that vaccination with the multi-epitope long peptide in combination with the PADRE peptide and CpG-ODN induced expansion of subpopulations of CD4+ and CD8+ cells producing IFN-γ, the average tumor size in the vaccinated mice was less than that of the other groups, and tumor growth was inhibited in 40% of the mice in the vaccinated group. The mean survival time was 82.6 ± 1.25 days in mice vaccinated with P5+435 + CpG+ PADRE. Our results demonstrate that inclusion of PADRE and CpG with the peptide vaccine enhanced significant tumor specific-immune responses in vaccinated mice.

  18. Peptide-specific T helper cells identified by MHC class II tetramers differentiate into several subtypes upon immunization with CAF01 adjuvanted H56 tuberculosis vaccine formulation.

    Science.gov (United States)

    Prota, Gennaro; Christensen, Dennis; Andersen, Peter; Medaglini, Donata; Ciabattini, Annalisa

    2015-11-27

    CD4(+) T-cell priming is an essential step in vaccination due to the key role of T helper cells in driving both effector and memory immune responses. Here we have characterized in C57BL/6 mice the T helper subtype differentiation among tetramer-specific CD4(+) T cells primed by subcutaneous immunization with the tuberculosis vaccine antigen H56 plus the adjuvant CAF01. Peptide-specific population identified by the MHC class II tetramers differentiated into several T helper subtypes upon antigen encounter, and the frequency of subpopulations differed according to their localization. Th1 (CXCR3(+)T-bet(+)), Tfh (CXCR5(+)PD-1(+)Bcl-6(+)) and RORγt(+) cells were induced in the lymph nodes draining the immunization site (dLN), while Th1 cells were the predominant subtype in the spleen. In addition, CD4(+) T cells co-expressing multiple T-cell lineage-specifying transcription factors were also detected. In the lungs, most of the tetramer-binding T cells were RORγt(+), while Tfh and Th1 cells were absent. After boosting, a higher frequency of tetramer-binding cells co-expressing the markers CD44 and CD127 was detected compared to primed cells, and cells showed a prevalent Th1 phenotype in both dLN and spleens, while Tfh cells were significantly reduced. In conclusion, these data demonstrate that parenteral immunization with H56 and CAF01 elicits a distribution of antigen-specific CD4(+) T cells in both lymphoid tissues and lungs, and gives rise to multiple T helper subtypes, that differ depending on localization and following reactivation.

  19. Liposome-Based Adjuvants for Subunit Vaccines

    DEFF Research Database (Denmark)

    Tandrup Schmidt, Signe; Foged, Camilla; Rades, Thomas

    2016-01-01

    The development of subunit vaccines has become very attractive in recent years due to their superior safety profiles as compared to traditional vaccines based on live attenuated or whole inactivated pathogens, and there is an unmet medical need for improved vaccines and vaccines against pathogens...... for which no effective vaccines exist. The subunit vaccine technology exploits pathogen subunits as antigens, e.g., recombinant proteins or synthetic peptides, allowing for highly specific immune responses against the pathogens. However, such antigens are usually not sufficiently immunogenic to induce...... been licensed for use in human vaccines, and they mainly stimulate humoral immunity. Thus, there is an unmet demand for the development of safe and efficient adjuvant systems that can also stimulate cell-mediated immunity (CMI). Adjuvants constitute a heterogeneous group of compounds, which can broadly...

  20. A booster vaccine expressing a latency-associated antigen augments BCG induced immunity and confers enhanced protection against tuberculosis.

    Directory of Open Access Journals (Sweden)

    Bappaditya Dey

    Full Text Available BACKGROUND: In spite of a consistent protection against tuberculosis (TB in children, Mycobacterium bovis Bacille Calmette-Guerin (BCG fails to provide adequate protection against the disease in adults as well as against reactivation of latent infections or exogenous reinfections. It has been speculated that failure to generate adequate memory T cell response, elicitation of inadequate immune response against latency-associated antigens and inability to impart long-term immunity against M. tuberculosis infections are some of the key factors responsible for the limited efficiency of BCG in controlling TB. METHODS/PRINCIPAL FINDINGS: In this study, we evaluated the ability of a DNA vaccine expressing α-crystallin--a key latency antigen of M. tuberculosis to boost the BCG induced immunity. 'BCG prime-DNA boost' regimen (B/D confers robust protection in guinea pigs along with a reduced pathology in comparison to BCG vaccination (1.37 log(10 and 1.96 log(10 fewer bacilli in lungs and spleen, respectively; p<0.01. In addition, B/D regimen also confers enhanced protection in mice. Further, we show that B/D immunization in mice results in a heightened frequency of PPD and antigen specific multi-functional CD4 T cells (3(+ simultaneously producing interferon (IFNγ, tumor necrosis factor (TNFα and interleukin (IL2. CONCLUSIONS/SIGNIFICANCE: These results clearly indicate the superiority of α-crystallin based B/D regimen over BCG. Our study, also demonstrates that protection against TB is predictable by an increased frequency of 3(+ Th1 cells with superior effector functions. We anticipate that this study would significantly contribute towards the development of superior booster vaccines for BCG vaccinated individuals. In addition, this regimen can also be expected to reduce the risk of developing active TB due to reactivation of latent infection.

  1. Antigenicity and Immunogenicity of Salmonella enteritidis: Its Implication for Diagnosis and Development of Local Isolate Vaccine for Poultry

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    Tati Ariyanti

    2008-12-01

    Full Text Available Genus Salmonella consists of more than 2,400 serovars, which can be identified by means of serological method based on the variation of their somatic (O, flagellar (H and capsular antigens (Vi. Salmonella serovars which are able to cause disease in animal or domestic animal are limited, such as: S. pullorum and S. gallinarum which are well adapted to poultry, cause fowl typhoid, S. cholerasuis causes disease in swine. S. typhimurium and S. enteritidis can infect all animals and humans. S. typhimurium and S. enteritidis could be isolated from salmonellosis of poultry, meat, milk and eggs. The prevalence of those isolates within the last two decades tends to increase. Pathogenic Salmonella serovars can infect both animals and humans, colonize the intestinal epithelial cells lead to diarrhoea. Salmonella spp. may enter the lower layer of epithelial cells and the lymphoid vascular system. Humoral antibody and cell mediated immunity responses may develop. Extraintestinal shedding or dissemination of Salmonella spp. may occur and multiply, this may cause latent infections and spread to the environment. Serologic diagnosis of infected animals can be done by means of serum or whole blood agglutination tests with whole cell antigen or ELISA with LPS coated tray, might demonstrate cross reactions among serovars within the one group. ELISA antibody by using fimbrial SEF14 antigen demonstrated specific diagnosis of S. enteritidis infection. The use of S. enteritidis inactive vaccines stimulates high humoral antibody response and protection against challenged homologous serovar within one group (D. The secretory antibody in mucosal surface of intestine and cell mediated immunity were not stimulated after vaccination with inactive Salmonella vaccine. Inactive vaccines (local isolate of S. enteritidis which was developed and evaluated on experimental layer chicken produced protection against challenged homologous and may be used to control vertical

  2. First evaluation of the serum level of anti-hepatitis B surface antigen after vaccination in Libya.

    Science.gov (United States)

    Madour, A; Alkout, A; Vanin, S

    2013-12-01

    The hepatitis B virus (HBV) vaccination schedule in Libya follows international recommendations (1st dose at birth, 2nd after 1 month and 3rd after 6 months). This research aimed to evaluate the long-term protection of the HBV immunization programme in Tripoli and to determine the best age to administer booster doses. Serum levels of hepatitis B surface antigen were determined in 277 randomly selected children aged 1-12 years. The response to HBV vaccine in 1-3-year-olds was 93.2%, but this declined with age and at 7-9 years after initial vaccination only 53.1% of children had protective titres (> or = 10 mIU/mL). No significant differences between males and females in antibody persistence or response to vaccine were observed. We recommend continuing the HBV vaccination programme and that a booster dose be given to 6-year-old children to ensure maximum protection during the period of school entry and beyond.

  3. Definition of a physiologic aging autoantigen by using synthetic peptides of membrane protein band 3: localization of the active antigenic sites.

    Science.gov (United States)

    Kay, M M; Marchalonis, J J; Hughes, J; Watanabe, K; Schluter, S F

    1990-08-01

    Senescent cell antigen (SCA), an aging antigen, is a protein that appears on old cells and marks them for removal by the immune system in mammals. It is derived from band 3, a ubiquitous membrane transport protein found in diverse cell types and tissues. We have used synthetic peptides to identify aging antigenic sites on band 3, using a competitive inhibition assay and immunoblotting with IgG directed against the aging antigen on old cells. Results indicate that: (i) the active antigenic sites of the aging antigen reside on membrane protein band 3 residues that are extracellular regions implicated in anion transport (residues 538-554 and 788-827); (ii) a putative ankyrin-binding-region peptide is not involved in SCA activity; and (iii) carbohydrate moieties are not required for the antigenicity or recognition of SCA because synthetic peptides alone abolish binding of senescent cell IgG to erythrocytes. One of the putative transport sites that contributes to the aging antigen is located toward the carboxyl terminus. A model of band 3 is presented. Localization of the active antigenic site on the band 3 molecule facilitates definition of the molecular changes occurring during aging that initiate molecular as well as cellular degeneration. PMID:1696010

  4. Protective Antigen-Specific Memory B Cells Persist Years after Anthrax Vaccination and Correlate with Humoral Immunity

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    Lori Garman

    2014-08-01

    Full Text Available Anthrax Vaccine Adsorbed (AVA generates short-lived protective antigen (PA specific IgG that correlates with in vitro toxin neutralization and protection from Bacillus anthracis challenge. Animal studies suggest that when PA-specific IgG has waned, survival after spore challenge correlates with an activation of PA-specific memory B cells. Here, we characterize the quantity and the longevity of AVA-induced memory B cell responses in humans. Peripheral blood mononuclear cells (PBMCs from individuals vaccinated ≥3 times with AVA (n = 50 were collected early (3–6 months, n = 27 or late after their last vaccination (2–5 years, n = 23, pan-stimulated, and assayed by ELISPOT for total and PA-specific memory B cells differentiated into antibody secreting cells (ASCs. PA-specific ASC percentages ranged from 0.02% to 6.25% (median: 1.57% and did not differ between early and late post-vaccination individuals. PA-specific ASC percentages correlated with plasma PA-specific IgG (r = 0.42, p = 0.03 and toxin neutralization (r = 0.52, p = 0.003 early post vaccination. PA-specific ASC percentages correlated with supernatant anti-PA both early (r = 0.60, p = 0.001 and late post vaccination (r = 0.71, p < 0.0001. These data suggest PA-specific memory B cell responses are long-lived and can be estimated after recent vaccination by the magnitude and neutralization capacity of the humoral response.

  5. Lysosome-associated membrane glycoprotein (LAMP)--preliminary study on a hidden antigen target for vaccination against schistosomiasis.

    Science.gov (United States)

    Nawaratna, Sujeevi S K; Gobert, Geoffrey N; Willis, Charlene; Mulvenna, Jason; Hofmann, Andreas; McManus, Donald P; Jones, Malcolm K

    2015-01-01

    Our previously reported gene atlasing of schistosome tissues revealed transcripts that were highly enriched in the digestive tract of Schistosoma mansoni. From these, we selected two candidates, Sm-LAMP and Sm-NPC2 for testing as vaccine targets. The two molecules were selected on the basis of relatively high expression in the gastrodermis, their potentially important biological function, divergence from homologous molecules of the host and possible apical membrane expression in the gastrodermis. Bacterially expressed recombinant peptides corresponding to regions excluding trans-membrane domains of the selected vaccine targets were used in blinded vaccine trials in CBA mice using alum-CpG as adjuvant. Vaccine trials using the recombinant insoluble Sm-LAMP protein showed 16-25% significant reduction in total worm burden. Faecal egg count reduction was 52% and 60% in two trials, respectively, with similar results for the solubly expressed protein. Liver egg burden was reduced significantly (20% and 38%) with an insoluble recombinant Sm-LAMP in two trials, but not with the soluble recombinant form. Parasite fecundity was not affected by either Sm-LAMP protein preparations in the trials. It is concluded that Sm-LAMP may provide limited protection towards S. mansoni infections but could be used in combination with other vaccine candidates, to provide more comprehensive protection. PMID:26472258

  6. Vaccination with human induced pluripotent stem cells creates an antigen-specific immune response against HIV-1 gp160

    Directory of Open Access Journals (Sweden)

    Shinji eYoshizaki

    2011-02-01

    Full Text Available Induced pluripotent stem cells (iPSCs are artificially derived from somatic cells that have been transduced with defined reprogramming factors. A previous report has indicated the possibility of using iPSCs as an immune stimulator to generate antigen-specific immunity. In our current study, we have investigated whether human iPSCs (hiPSCs have the ability to enhance specific immune response against a human immunodeficiency virus type 1 (HIV-1 antigen in a xenogenic mouse model. Our results show that BALB/c mice immunized with hiPSCs transduced with an adenoviral vector encoding HIV-1 gp160 exhibited prominent antigen-specific cellular immune responses. We further found that pre-treatment of hiPSCs with ionizing radiation promotes the secretion of pro-inflammatory cytokines such as interleukin-1 alpha (IL-1α, IL-12 and IL-18. These cytokines might promote the activation of antigen-presenting cells and the effective induction of cellular immunity. Our present findings thus demonstrate that a hiPSCs-based vaccine has the potential to generate cellular immunity against viral antigens such as HIV-1 gp160 in a xenogenic condition.

  7. Sequence-based prediction for vaccine strain selection and identification of antigenic variability in foot-and-mouth disease virus.

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    Richard Reeve

    Full Text Available Identifying when past exposure to an infectious disease will protect against newly emerging strains is central to understanding the spread and the severity of epidemics, but the prediction of viral cross-protection remains an important unsolved problem. For foot-and-mouth disease virus (FMDV research in particular, improved methods for predicting this cross-protection are critical for predicting the severity of outbreaks within endemic settings where multiple serotypes and subtypes commonly co-circulate, as well as for deciding whether appropriate vaccine(s exist and how much they could mitigate the effects of any outbreak. To identify antigenic relationships and their predictors, we used linear mixed effects models to account for variation in pairwise cross-neutralization titres using only viral sequences and structural data. We identified those substitutions in surface-exposed structural proteins that are correlates of loss of cross-reactivity. These allowed prediction of both the best vaccine match for any single virus and the breadth of coverage of new vaccine candidates from their capsid sequences as effectively as or better than serology. Sub-sequences chosen by the model-building process all contained sites that are known epitopes on other serotypes. Furthermore, for the SAT1 serotype, for which epitopes have never previously been identified, we provide strong evidence--by controlling for phylogenetic structure--for the presence of three epitopes across a panel of viruses and quantify the relative significance of some individual residues in determining cross-neutralization. Identifying and quantifying the importance of sites that predict viral strain cross-reactivity not just for single viruses but across entire serotypes can help in the design of vaccines with better targeting and broader coverage. These techniques can be generalized to any infectious agents where cross-reactivity assays have been carried out. As the parameterization

  8. Merozoite Surface Antigen 2 Proteins of Babesia bovis Vaccine Breakthrough Isolates Contain a Unique Hypervariable Region Composed of Degenerate Repeats

    Science.gov (United States)

    Berens, Shawn J.; Brayton, Kelly A.; Molloy, John B.; Bock, Russell E.; Lew, Ala E.; McElwain, Terry F.

    2005-01-01

    The merozoite surface antigen 2 (MSA-2) proteins of Babesia bovis are members of the variable merozoite surface antigen (VMSA) family that have been implicated in erythrocyte invasion and are important targets for antibody-mediated blocking of invasion. Extensive sequence variation in another VMSA member, MSA-1, has been shown in all vaccine breakthrough isolates. To test the hypothesis that the msa-2 genes of vaccine breakthrough isolates would also encode a diverse set of proteins, the complete msa-2 locus was characterized from 12 Australian B. bovis strains and isolates, including two vaccine strains and eight vaccine breakthrough isolates, and compared to the loci in previously and newly characterized American strains. In contrast to American strains, the msa-2 loci of all Australian strains and isolates examined contain, in addition to msa-2c, only a solitary gene (designated msa-2a/b) closely related to American strain msa-2a and msa-2b. Nevertheless, the proteins encoded by these genes are quite diverse both between and within geographic regions and harbor evidence of genetic exchange among other VMSA family members, including msa-1. Moreover, all but one of the Australian breakthrough isolate MSA-2a/b proteins is markedly different from the vaccine strain from which immune escape occurred, consistent with their role in strain-specific protective immunity. The densest distribution of polymorphisms occurs in a hypervariable region (HVR) within the carboxy third of the molecule that is highly proline rich. Variation in length and content of the HVR is primarily attributable to differences in the order and number of degenerate nucleotide repeats encoding three motifs of unknown function. PMID:16239512

  9. Blood stage malaria vaccine eliciting high antigen-specific antibody concentrations confers no protection to young children in Western Kenya.

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    Bernhards R Ogutu

    Full Text Available The antigen, falciparum malaria protein 1 (FMP1, represents the 42-kDa C-terminal fragment of merozoite surface protein-1 (MSP-1 of the 3D7 clone of P. falciparum. Formulated with AS02 (a proprietary Adjuvant System, it constitutes the FMP1/AS02 candidate malaria vaccine. We evaluated this vaccine's safety, immunogenicity, and efficacy in African children.A randomised, double-blind, Phase IIb, comparator-controlled trial.The trial was conducted in 13 field stations of one mile radii within Kombewa Division, Nyanza Province, Western Kenya, an area of holoendemic transmission of P. falciparum. We enrolled 400 children aged 12-47 months in general good health.Children were randomised in a 1ratio1 fashion to receive either FMP1/AS02 (50 microg or Rabipur(R rabies vaccine. Vaccinations were administered on a 0, 1, and 2 month schedule. The primary study endpoint was time to first clinical episode of P. falciparum malaria (temperature >/=37.5 degrees C with asexual parasitaemia of >/=50,000 parasites/microL of blood occurring between 14 days and six months after a third dose. Case detection was both active and passive. Safety and immunogenicity were evaluated for eight months after first immunisations; vaccine efficacy (VE was measured over a six-month period following third vaccinations.374 of 400 children received all three doses and completed six months of follow-up. FMP1/AS02 had a good safety profile and was well-tolerated but more reactogenic than the comparator. Geometric mean anti-MSP-1(42 antibody concentrations increased from1.3 microg/mL to 27.3 microg/mL in the FMP1/AS02 recipients, but were unchanged in controls. 97 children in the FMP1/AS02 group and 98 controls had a primary endpoint episode. Overall VE was 5.1% (95% CI: -26% to +28%; p-value = 0.7.FMP1/AS02 is not a promising candidate for further development as a monovalent malaria vaccine. Future MSP-1(42 vaccine development should focus on other formulations and antigen constructs

  10. Role of T-cell receptor V beta 8.3 peptide vaccine in the prevention of experimental autoimmune uveoretinitis

    NARCIS (Netherlands)

    Zhang, R.; Yang, P.Z.; Wu, C.Y.; Jin, H.L.; Li, B.; Huang, X.; Zhou, H.; Gao, Y.; Zhu, L.; Kijlstra, A.

    2006-01-01

    T-cell receptor (TCR) plays an important role in the development of autoimmune diseases. Recently, it was reported that immunization of animals with TCR peptide derived from the pathogenic cells could prevent autoimmune diseases. The aim of this study was to investigate whether vaccination with a sy

  11. Human anti-anthrax protective antigen neutralizing monoclonal antibodies derived from donors vaccinated with anthrax vaccine adsorbed

    OpenAIRE

    Sawada-Hirai, Ritsuko; Jiang, Ivy; Wang, Fei; Sun, Shu Man; Nedellec, Rebecca; Ruther, Paul; Alvarez, Alejandro; Millis, Diane; Morrow, Phillip R.; Kang, Angray S

    2004-01-01

    Background Potent anthrax toxin neutralizing human monoclonal antibodies were generated from peripheral blood lymphocytes obtained from Anthrax Vaccine Adsorbed (AVA) immune donors. The anti-anthrax toxin human monoclonal antibodies were evaluated for neutralization of anthrax lethal toxin in vivo in the Fisher 344 rat bolus toxin challenge model. Methods Human peripheral blood lymphocytes from AVA immunized donors were engrafted into severe combined immunodeficient (SCID) mice. Vaccination w...

  12. Induction of tolerance against the arthritogenic antigen with type-II collagen peptide-linked soluble MHC class II molecules

    Science.gov (United States)

    Park, Yoon-Kyung; Jung, Sundo; Park, Se-Ho

    2016-01-01

    In murine collagen-induced arthritis (CIA), self-reactive T cells can recognize peptide antigens derived from type-II collagen (CII). Activation of T cells is an important mediator of autoimmune diseases. Thus, T cells have become a focal point of study to treat autoimmune diseases. In this study, we evaluated the efficacy of recombinant MHC class II molecules in the regulation of antigen-specific T cells by using a self peptide derived from CII (CII260-274; IAGFKGEQGPKGEPG) linked to mouseI-Aq in a murine CIA model. We found that recombinant I-Aq/CII260-274 molecules could be recognized by CII-specific T cells and inhibit the same T cells in vitro. Furthermore, the development of CIA in mice was successfully prevented by in vivo injection of recombinant I-Aq/CII260-274 molecules. Thus, treatment with recombinant soluble MHC class II molecules in complex with an immunodominant self-peptide might offer a potential therapeutic for chronic inflammation in autoimmune disease such as rheumatoid arthritis. [BMB Reports 2016; 49(6): 331-336 PMID:26779996

  13. The malaria candidate vaccine liver stage antigen-3 is highly conserved in Plasmodium falciparum isolates from diverse geographical areas

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    Druilhe Pierre

    2009-10-01

    Full Text Available Abstract Background A high level of genetic stability has been formerly identified in segments of the gene coding for the liver stage antigen-3 (LSA-3, a subunit vaccine candidate against Plasmodium falciparum. The exploration of lsa-3 polymorphisms was extended to the whole sequence of this large antigen in 20 clinical isolates from four geographical areas; Senegal, Comoro islands, Brazil and Thailand. Methods The whole 4680 bp genomic sequence of lsa-3 was amplified by polymerase chain reaction and sequenced. The clinical isolate sequences were aligned on the sequence of the laboratory reference P. falciparum strain 3D7. Results The non-repeated sequence of lsa-3 was very well conserved with only a few allelic variations scattered along the sequence. Interestingly, a formerly identified immunodominant region, employed for the majority of pre-clinical vaccine development, was totally conserved at the genetic level. The most significant variations observed were in the number and organization of tetrapeptide repeated units, but not in their composition, resulting in different lengths of these repeated regions. The shorter repeated regions were from Brazilian origin. A correlation between the geographical distribution of the parasites with single nucleotide polymorphisms was not detected. Conclusion The lack of correlation between allelic polymorphisms with a specific transmission pressure suggests that LSA-3 is a structurally constrained molecule. The unusual characteristics of the lsa-3 gene make the molecule an interesting candidate for a subunit vaccine against malaria.

  14. Vaccination with conserved regions of erythrocyte-binding antigens induces neutralizing antibodies against multiple strains of Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Julie Healer

    Full Text Available BACKGROUND: A highly effective vaccine against Plasmodium falciparum malaria should induce potent, strain transcending immunity that broadly protects against the diverse population of parasites circulating globally. We aimed to identify vaccine candidates that fulfill the criteria. METHODS: We have measured growth inhibitory activity of antibodies raised to a range of antigens to identify those that can efficiently block merozoite invasion for geographically diverse strains of P. falciparum. RESULTS: This has shown that the conserved Region III-V, of the P. falciparum erythrocyte-binding antigen (EBA-175 was able to induce antibodies that potently inhibit merozoite invasion across diverse parasite strains, including those reliant on invasion pathways independent of EBA-175 function. Additionally, the conserved RIII-V domain of EBA-140 also induced antibodies with strong in vitro parasite growth inhibitory activity. CONCLUSION: We identify an alternative, highly conserved region (RIV-V of EBA-175, present in all EBA proteins, that is the target of potent, strain transcending neutralizing antibodies, that represents a strong candidate for development as a component in a malaria vaccine.

  15. Targeting hepatitis B virus antigens to dendritic cells by heat shock protein to improve DNA vaccine potency

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate a novel DNA vaccination based upon expression of the HBV e antigen fused to a heat shock protein (HSP) as a strategy to enhance DNA vaccine potency.METHODS: A pCMV-HBeAg-HSP DNA vaccine and a control DNA vaccine were generated. Mice were immunized with these different construct. Immune responses were measured 2 wk after a second immunization by a T cell response assay, CTL cytotoxicity assay, and an antibody assay in C57BL/6 and BALB/c mice. CT26-HBeAg tumor cell challenge test in vivo was performed in BALB/c mice to monitor anti-tumor immune responses.RESULTS: In the mice immunized with pCMV-HBe-HSP DNA, superior CTL activity to target HBV-positive target cells was observed in comparison with mice immunized with pCMV-HBeAg (44% ± 5% vs 30% ± 6% in E: T > 50:1, P < 0.05). ELISPOT assays showed a stronger T-cell response from mice immunized with pCMV-HBe-HSP than that from pCMV-HBeAg immunized animals when stimulated either with MHC class Ⅰ or class Ⅱ epitopes derived from HBeAg (74% ± 9% vs 31% ± 6%, P < 0.01). ELISA assays revealed an enhanced HBeAg antibody response from mice immunized with pCMV-HBe-HSP than from those immunized with pCMV-HBeAg. The lowest tumor incidence and the slowest tumor growth were observed in mice immunized with pCMV-HBe-HSP when challenged with CT26-HBeAg.CONCLUSION: The results of this study demonstrate a broad enhancement of antigen-specific CD4+ helper,CD8+ cytotoxic T-cell, and B-cell responses by a novel DNA vaccination strategy. They also proved a stronger antigen-specific immune memory, which may be superior to currently described HBV DNA vaccination strategies for the treatment of chronic HBV infection.

  16. Neutralizing Antibody Responses to Antigenically Drifted Influenza A(H3N2) Viruses among Children and Adolescents following 2014-2015 Inactivated and Live Attenuated Influenza Vaccination

    Science.gov (United States)

    Martin, Judith M.; Gross, F. Liaini; Jefferson, Stacie; Cole, Kelly Stefano; Archibald, Crystal Ann; Nowalk, Mary Patricia; Susick, Michael; Moehling, Krissy; Spencer, Sarah; Chung, Jessie R.; Flannery, Brendan; Zimmerman, Richard K.

    2016-01-01

    Human influenza A(H3N2) viruses that predominated during the moderately severe 2014-2015 influenza season differed antigenically from the vaccine component, resulting in reduced vaccine effectiveness (VE). To examine antibody responses to 2014-2015 inactivated influenza vaccine (IIV) and live-attenuated influenza vaccine (LAIV) among children and adolescents, we collected sera before and after vaccination from 150 children aged 3 to 17 years enrolled at health care facilities. Hemagglutination inhibition (HI) assays were used to assess the antibody responses to vaccine strains. We evaluated cross-reactive antibody responses against two representative A(H3N2) viruses that had antigenically drifted from the A(H3N2) vaccine component using microneutralization (MN) assays. Postvaccination antibody titers to drifted A(H3N2) viruses were higher following receipt of IIV (MN geometric mean titers [GMTs], 63 to 68; 38 to 45% achieved seroconversion) versus LAIV (MN GMT, 22; only 3 to 5% achieved seroconversion). In 9- to 17-year-olds, the highest MN titers were observed among IIV-vaccinated individuals who had received LAIV in the previous season. Among all IIV recipients aged 3 to 17 years, the strongest predictor of antibody responses to the drifted viruses was the prevaccination titers to the vaccine strain. The results of our study suggest that in an antigenically drifted influenza season, vaccination still induced cross-reactive antibody responses to drifted circulating A(H3N2) viruses, although higher antibody titers may be required for protection. Antibody responses to drifted A(H3N2) viruses following vaccination were influenced by multiple factors, including vaccine type and preexisting immunity from prior exposure. PMID:27558294

  17. γδ T cells recognize the insulin B:9-23 peptide antigen when it is dimerized through thiol oxidation.

    Science.gov (United States)

    Aydintug, M Kemal; Zhang, Li; Wang, Chao; Liang, Dongchun; Wands, J M; Michels, Aaron W; Hirsch, Brooke; Day, Brian J; Zhang, Gongyi; Sun, Deming; Eisenbarth, George S; O'Brien, Rebecca L; Born, Willi K

    2014-08-01

    The insulin peptide B:9-23 is a natural antigen in the non-obese diabetic (NOD) mouse model of type 1 diabetes (T1D). In addition to αβ T cells and B cells, γδ T cells recognize the peptide and infiltrate the pancreatic islets where the peptide is produced within β cells. The peptide contains a cysteine in position 19 (Cys19), which is required for the γδ but not the αβ T cell response, and a tyrosine in position 16 (Tyr16), which is required for both. A peptide-specific mAb, tested along with the T cells, required neither of the two amino acids to bind the B:9-23 peptide. We found that γδ T cells require Cys19 because they recognize the peptide antigen in an oxidized state, in which the Cys19 thiols of two peptide molecules form a disulfide bond, creating a soluble homo-dimer. In contrast, αβ T cells recognize the peptide antigen as a reduced monomer, in complex with the MHCII molecule I-A(g7). Unlike the unstructured monomeric B:9-23 peptide, the γδ-stimulatory homo-dimer adopts a distinct secondary structure in solution, which differs from the secondary structure of the corresponding portion of the native insulin molecule. Tyr16 is required for this adopted structure of the dimerized insulin peptide as well as for the γδ response to it. This observation is consistent with the notion that γδ T cell recognition depends on the secondary structure of the dimerized insulin B:9-23 antigen.

  18. Detection and Tracking of NY-ESO-1-Specific CD8+ T Cells by High-Throughput T Cell Receptor β (TCRB Gene Rearrangements Sequencing in a Peptide-Vaccinated Patient.

    Directory of Open Access Journals (Sweden)

    Manami Miyai

    Full Text Available Comprehensive immunological evaluation is crucial for monitoring patients undergoing antigen-specific cancer immunotherapy. The identification and quantification of T cell responses is most important for the further development of such therapies. Using well-characterized clinical samples from a high responder patient (TK-f01 in an NY-ESO-1f peptide vaccine study, we performed high-throughput T cell receptor β-chain (TCRB gene next generation sequencing (NGS to monitor the frequency of NY-ESO-1-specific CD8+ T cells. We compared these results with those of conventional immunological assays, such as IFN-γ capture, tetramer binding and limiting dilution clonality assays. We sequenced human TCRB complementarity-determining region 3 (CDR3 rearrangements of two NY-ESO-1f-specific CD8+ T cell clones, 6-8L and 2F6, as well as PBMCs over the course of peptide vaccination. Clone 6-8L possessed the TCRB CDR3 gene TCRBV11-03*01 and BJ02-01*01 with amino acid sequence CASSLRGNEQFF, whereas 2F6 possessed TCRBV05-08*01 and BJ02-04*01 (CASSLVGTNIQYF. Using these two sequences as models, we evaluated the frequency of NY-ESO-1-specific CD8+ T cells in PBMCs ex vivo. The 6-8L CDR3 sequence was the second most frequent in PBMC and was present at high frequency (0.7133% even prior to vaccination, and sustained over the course of vaccination. Despite a marked expansion of NY-ESO-1-specific CD8+ T cells detected from the first through 6th vaccination by tetramer staining and IFN-γ capture assays, as evaluated by CDR3 sequencing the frequency did not increase with increasing rounds of peptide vaccination. By clonal analysis using 12 day in vitro stimulation, the frequency of B*52:01-restricted NY-ESO-1f peptide-specific CD8+ T cells in PBMCs was estimated as only 0.0023%, far below the 0.7133% by NGS sequencing. Thus, assays requiring in vitro stimulation might be underestimating the frequency of clones with lower proliferation potential. High-throughput TCRB

  19. Detection and Tracking of NY-ESO-1-Specific CD8+ T Cells by High-Throughput T Cell Receptor β (TCRB) Gene Rearrangements Sequencing in a Peptide-Vaccinated Patient.

    Science.gov (United States)

    Miyai, Manami; Eikawa, Shingo; Hosoi, Akihiro; Iino, Tamaki; Matsushita, Hirokazu; Isobe, Midori; Uenaka, Akiko; Udono, Heiichiro; Nakajima, Jun; Nakayama, Eiichi; Kakimi, Kazuhiro

    2015-01-01

    Comprehensive immunological evaluation is crucial for monitoring patients undergoing antigen-specific cancer immunotherapy. The identification and quantification of T cell responses is most important for the further development of such therapies. Using well-characterized clinical samples from a high responder patient (TK-f01) in an NY-ESO-1f peptide vaccine study, we performed high-throughput T cell receptor β-chain (TCRB) gene next generation sequencing (NGS) to monitor the frequency of NY-ESO-1-specific CD8+ T cells. We compared these results with those of conventional immunological assays, such as IFN-γ capture, tetramer binding and limiting dilution clonality assays. We sequenced human TCRB complementarity-determining region 3 (CDR3) rearrangements of two NY-ESO-1f-specific CD8+ T cell clones, 6-8L and 2F6, as well as PBMCs over the course of peptide vaccination. Clone 6-8L possessed the TCRB CDR3 gene TCRBV11-03*01 and BJ02-01*01 with amino acid sequence CASSLRGNEQFF, whereas 2F6 possessed TCRBV05-08*01 and BJ02-04*01 (CASSLVGTNIQYF). Using these two sequences as models, we evaluated the frequency of NY-ESO-1-specific CD8+ T cells in PBMCs ex vivo. The 6-8L CDR3 sequence was the second most frequent in PBMC and was present at high frequency (0.7133%) even prior to vaccination, and sustained over the course of vaccination. Despite a marked expansion of NY-ESO-1-specific CD8+ T cells detected from the first through 6th vaccination by tetramer staining and IFN-γ capture assays, as evaluated by CDR3 sequencing the frequency did not increase with increasing rounds of peptide vaccination. By clonal analysis using 12 day in vitro stimulation, the frequency of B*52:01-restricted NY-ESO-1f peptide-specific CD8+ T cells in PBMCs was estimated as only 0.0023%, far below the 0.7133% by NGS sequencing. Thus, assays requiring in vitro stimulation might be underestimating the frequency of clones with lower proliferation potential. High-throughput TCRB sequencing using NGS

  20. Structural analysis of peptides capable of binding to more than one Ia antigen

    DEFF Research Database (Denmark)

    Sette, A; Buus, S; Colon, S;

    1989-01-01

    The Ia binding regions were analyzed for three unrelated peptide Ag (sperm whale myoglobin 106-118, influenza hemagglutinin 130-142, and lambda repressor protein 12-26) for which binding to more than one Ia molecule has previously been demonstrated. By determining the binding profile of three...... separate series of truncated synthetic peptides, it was found that in all three cases the different Ia reactivities mapped to largely overlapping regions of the peptides; although, for two of the peptides, the regions involved in binding the different Ia specificities were distinct. Moreover, subtle...... differences were found to dramatically influence some, but not other, Ia reactivities. Using a large panel of synthetic peptides it was found that a significant correlation exists between the capacity of peptides to interact with different alleles of the same molecule (i.e., IAd and IAk), but no correlation...

  1. Establishment of an in vivo potency assay for the recombinant hepatit is B surface antigen in monovalent and combined vaccines

    Directory of Open Access Journals (Sweden)

    Mabel Izquierdo-López

    2014-12-01

    Full Text Available In this paper the development of potency assay in animals (mice was made, with the objective of demonstrating the immunogenic power of the recombinant Hepatitis B surface antigen in monovalent and combined vaccines, produced at the Center of Genetic Engineering and Biotechnology. The potency test is a parameter in quality control and it is also a tool to demonstrate the consistency of the production process. Parameters such as duration of the test, number of animals in the test, as well as different areas for the maintenance of the animals were evaluated. The results on the applicability of the potency test, to two presentations of the vaccines; monovalent Heberbiovac HB and pentavalent liquid in one vial Heberpenta-L are shown, for which specificity studies, evaluating different vaccine lots, the behavior of linearity, and parallelism, as well as establishing quality specification of the test were performed. This assay led to the obtainment of reliable results for the vaccines evaluated, the consistent evaluation of the immunogenic power and the monitoring of different production processes.

  2. Evaluation of Humoral Immunity to Mycobacterium tuberculosis-Specific Antigens for Correlation with Clinical Status and Effective Vaccine Development

    Directory of Open Access Journals (Sweden)

    Mamiko Niki

    2015-01-01

    Full Text Available Although tuberculosis remains a major global health problem, Bacille Calmette-Guérin (BCG is the only available vaccine. However, BCG has limited applications, and a more effective vaccine is needed. Cellular mediated immunity (CMI is thought to be the most important immune response for protection against Mycobacterium tuberculosis (Mtb. However, the recent failure of a clinical trial for a booster BCG vaccine and increasing evidence of antibody-mediated immunity prompted us to evaluate humoral immunity to Mtb-specific antigens. Using Enzyme-Linked ImmunoSpot and Enzyme-Linked ImmunoSorbent Assays, we observed less correlation of both CMI and IgG titers with patient clinical status, including serum concentration of C reactive protein. However, IgA titers against Mtb were significantly correlated with clinical status, suggesting that specific IgA antibodies protect against Mtb proliferation. In addition, in some cases, IgA antibody titers were significantly associated with the serum concentration of total albumin, which supports the idea that humoral immunity can be influenced by the nutritional status. Based on these observations, we propose that the induction of humoral immunity should be included as an option in TB vaccine development strategies.

  3. Evaluation of Humoral Immunity to Mycobacterium tuberculosis-Specific Antigens for Correlation with Clinical Status and Effective Vaccine Development.

    Science.gov (United States)

    Niki, Mamiko; Suzukawa, Maho; Akashi, Shunsuke; Nagai, Hideaki; Ohta, Ken; Inoue, Manabu; Niki, Makoto; Kaneko, Yukihiro; Morimoto, Kozo; Kurashima, Atsuyuki; Kitada, Seigo; Matsumoto, Sohkichi; Suzuki, Koichi; Hoshino, Yoshihiko

    2015-01-01

    Although tuberculosis remains a major global health problem, Bacille Calmette-Guérin (BCG) is the only available vaccine. However, BCG has limited applications, and a more effective vaccine is needed. Cellular mediated immunity (CMI) is thought to be the most important immune response for protection against Mycobacterium tuberculosis (Mtb). However, the recent failure of a clinical trial for a booster BCG vaccine and increasing evidence of antibody-mediated immunity prompted us to evaluate humoral immunity to Mtb-specific antigens. Using Enzyme-Linked ImmunoSpot and Enzyme-Linked ImmunoSorbent Assays, we observed less correlation of both CMI and IgG titers with patient clinical status, including serum concentration of C reactive protein. However, IgA titers against Mtb were significantly correlated with clinical status, suggesting that specific IgA antibodies protect against Mtb proliferation. In addition, in some cases, IgA antibody titers were significantly associated with the serum concentration of total albumin, which supports the idea that humoral immunity can be influenced by the nutritional status. Based on these observations, we propose that the induction of humoral immunity should be included as an option in TB vaccine development strategies. PMID:26568961

  4. Intranasal Vaccination Affords Localization and Persistence of Antigen-Specific CD8⁺ T Lymphocytes in the Female Reproductive Tract.

    Science.gov (United States)

    Singh, Shailbala; Schluns, Kimberly S; Yang, Guojun; Anthony, Scott M; Barry, Michael A; Sastry, K Jagannadha

    2016-03-17

    Immunization strategies generating large numbers of antigen-specific T cells in the female reproductive tract (FRT) can provide barrier protection against sexually-transmitted pathogens, such as the human immunodeficiency virus (HIV) and human papillomaviruses (HPV). The kinetics and mechanisms of regulation of vaccine-induced adaptive T cell-mediated immune responses in FRT are less well defined. We present here evidence for intranasal delivery of the model antigen ovalbumin (OVA) along with alpha-galactosylceramide adjuvant as a protein vaccine to induce significantly higher levels of antigen-specific effector and memory CD8⁺ T cells in the FRT, relative to other systemic and mucosal tissues. Antibody blocking of the CXCR3 receptor significantly reduced antigen-specific CD8⁺ T cells subsequent to intranasal delivery of the protein vaccine suggesting an important role for the CXCR3 chemokine-receptor signaling for T cell trafficking. Further, intranasal vaccination with an adenoviral vector expressing OVA or HIV-1 envelope was as effective as intramuscular vaccination for generating OVA- or ENV-specific immunity in the FRT. These results support the application of the needle-free intranasal route as a practical approach to delivering protein as well as DNA/virus vector-based vaccines for efficient induction of effector and memory T cell immunity in the FRT.

  5. Enhanced vaccine-induced CD8+ T cell responses to malaria antigen ME-TRAP by fusion to MHC class ii invariant chain.

    Directory of Open Access Journals (Sweden)

    Alexandra J Spencer

    Full Text Available The orthodox role of the invariant chain (CD74; Ii is in antigen presentation to CD4+ T cells, but enhanced CD8+ T cells responses have been reported after vaccination with vectored viral vaccines encoding a fusion of Ii to the antigen of interest. In this study we assessed whether fusion of the malarial antigen, ME-TRAP, to Ii could increase the vaccine-induced CD8+ T cell response. Following single or heterologous prime-boost vaccination of mice with a recombinant chimpanzee adenovirus vector, ChAd63, or recombinant modified vaccinia virus Ankara (MVA, higher frequencies of antigen-specific CD4+ and CD8+ T cells were observed, with the largest increases observed following a ChAd63-MVA heterologous prime-boost regimen. Studies in non-human primates confirmed the ability of Ii-fusion to augment the T cell response, where a 4-fold increase was maintained up to 11 weeks after the MVA boost. Of the numerous different approaches explored to increase vectored vaccine induced immunogenicity over the years, fusion to the invariant chain showed a consistent enhancement in CD8+ T cell responses across different animal species and may therefore find application in the development of vaccines against human malaria and other diseases where high levels of cell-mediated immunity are required.

  6. Cystine-knot peptides targeting cancer-relevant human cytotoxic T lymphocyte-associated antigen 4 (CTLA-4).

    Science.gov (United States)

    Maaß, Franziska; Wüstehube-Lausch, Joycelyn; Dickgießer, Stephan; Valldorf, Bernhard; Reinwarth, Michael; Schmoldt, Hans-Ulrich; Daneschdar, Matin; Avrutina, Olga; Sahin, Ugur; Kolmar, Harald

    2015-08-01

    Cystine-knot peptides sharing a common fold but displaying a notably large diversity within the primary structure of flanking loops have shown great potential as scaffolds for the development of therapeutic and diagnostic agents. In this study, we demonstrated that the cystine-knot peptide MCoTI-II, a trypsin inhibitor from Momordica cochinchinensis, can be engineered to bind to cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), an inhibitory receptor expressed by T lymphocytes, that has emerged as a target for the treatment of metastatic melanoma. Directed evolution was used to convert a cystine-knot trypsin inhibitor into a CTLA-4 binder by screening a library of variants using yeast surface display. A set of cystine-knot peptides possessing dissociation constants in the micromolar range was obtained; the most potent variant was synthesized chemically. Successive conjugation with neutravidin, fusion to antibody Fc domain or the oligomerization domain of C4b binding protein resulted in oligovalent variants that possessed enhanced (up to 400-fold) dissociation constants in the nanomolar range. Our data indicate that display of multiple knottin peptides on an oligomeric scaffold protein is a valid strategy to improve their functional affinity with ramifications for applications in diagnostics and therapy. PMID:25964162

  7. Proteolytic activity of prostate-specific antigen (PSA towards protein substrates and effect of peptides stimulating PSA activity.

    Directory of Open Access Journals (Sweden)

    Johanna M Mattsson

    Full Text Available Prostate-specific antigen (PSA or kallikrein-related peptidase-3, KLK3 exerts chymotrypsin-like proteolytic activity. The main biological function of PSA is the liquefaction of the clot formed after ejaculation by cleavage of semenogelins I and II in seminal fluid. PSA also cleaves several other substrates, which may explain its putative functions in prostate cancer and its antiangiogenic activity. We compared the proteolytic efficiency of PSA towards several protein and peptide substrates and studied the effect of peptides stimulating the activity of PSA with these substrates. An endothelial cell tube formation model was used to analyze the effect of PSA-degraded protein fragments on angiogenesis. We showed that PSA degrades semenogelins I and II much more efficiently than other previously identified protein substrates, e.g., fibronectin, galectin-3 and IGFBP-3. We identified nidogen-1 as a new substrate for PSA. Peptides B2 and C4 that stimulate the activity of PSA towards small peptide substrates also enhanced the proteolytic activity of PSA towards protein substrates. Nidogen-1, galectin-3 or their fragments produced by PSA did not have any effect on endothelial cell tube formation. Although PSA cleaves several other protein substrates, in addition to semenogelins, the physiological importance of this activity remains speculative. The PSA levels in prostate are very high, but several other highly active proteases, such as hK2 and trypsin, are also expressed in the prostate and may cleave protein substrates that are weakly cleaved by PSA.

  8. Grafting of a peptide probe for Prostate-Specific Antigen detection using diazonium electroreduction and click chemistry.

    Science.gov (United States)

    Strzemińska, I; Sainte Rose Fanchine, S; Anquetin, G; Reisberg, S; Noël, V; Pham, M C; Piro, B

    2016-07-15

    The main objective of this work was to validate a label-free electrochemical method of protein detection using peptides as capture probes. As a proof-of-concept, we used a 7 amino acids sequence (HSSKLQL) specific for Prostate Specific Antigen. We investigated various electrografting conditions of two anilines (2-[(4-aminophenyl)sulfanyl]-8-hydroxy-1,4-naphthoquinone and 4-azidoaniline) further converted in situ into their corresponding diazonium salts on glassy carbon electrodes. It was demonstrated that the best method to obtain a mixed layer is the simultaneous electroreduction of the two diazonium salts. 4-azidoaniline was used to covalently immobilize the ethynyl-functionalized peptide probe by click coupling, and the hydroxynaphthoquinone derivative plays the role of electrochemical transducer of the peptide-protein recognition. The proteolytic activity of PSA towards a small peptide substrate carrying streptavidin at its distal end was also investigated to design an original sensing architecture leading to a reagentless, label free, and "signal-on" PSA sensor. Without optimization, the limit of quantification can be estimated in the nM to pM range. PMID:26938492

  9. Expression of immunogenic epitopes of hepatitis B surface antigen with hybrid flagellin proteins by a vaccine strain of Salmonella.

    OpenAIRE

    Wu, J Y; Newton, S; Judd, A; Stocker, B; Robinson, W S

    1989-01-01

    A nonvirulent Salmonella dublin flagellin-negative, aromatic-dependent live vaccine strain has been used to express hepatitis B virus surface antigen epitopes in an immunogenic form. The envelope proteins of the virion are encoded by the S gene, which contains the pre-S1, pre-S2, and S coding regions. Synthetic oligonucleotides corresponding to amino acid residues S-(122-137) and pre-S2-(120-145) were inserted in-frame into the hypervariable region of a cloned Salmonella flagellin gene, and t...

  10. Malaria vaccine candidate antigen targeting the pre-erythrocytic stage of Plasmodium falciparum produced at high level in plants.

    Science.gov (United States)

    Voepel, Nadja; Boes, Alexander; Edgue, Güven; Beiss, Veronique; Kapelski, Stephanie; Reimann, Andreas; Schillberg, Stefan; Pradel, Gabriele; Fendel, Rolf; Scheuermayer, Matthias; Spiegel, Holger; Fischer, Rainer

    2014-11-01

    Plants have emerged as low-cost production platforms suitable for vaccines targeting poverty-related diseases. Besides functional efficacy, the stability, yield, and purification process determine the production costs of a vaccine and thereby the feasibility of plant-based production. We describe high-level plant production and functional characterization of a malaria vaccine candidate targeting the pre-erythrocytic stage of Plasmodium falciparum. CCT, a fusion protein composed of three sporozoite antigens (P. falciparum cell traversal protein for ookinetes and sporozoites [PfCelTOS], P. falciparum circumsporozoite protein [PfCSP], and P. falciparum thrombospondin-related adhesive protein [PfTRAP]), was transiently expressed by agroinfiltration in Nicotiana benthamiana leaves, accumulated to levels up to 2 mg/g fresh leaf weight (FLW), was thermostable up to 80°C and could be purified to >95% using a simple two-step procedure. Reactivity of sera from malaria semi-immune donors indicated the immunogenic conformation of the purified fusion protein consisting of PfCelTOS, PfCSP_TSR, PfTRAP_TSR domains (CCT) protein. Total IgG from the CCT-specific mouse immune sera specifically recognized P. falciparum sporozoites in immunofluorescence assays and induced up to 35% inhibition in hepatocyte invasion assays. Featuring domains from three promising sporozoite antigens with different roles (attachment and cell traversal) in the hepatocyte invasion process, CCT has the potential to elicit broader immune responses against the pre-erythrocytic stage of P. falciparum and represents an interesting new candidate, also as a component of multi-stage, multi-subunit malaria vaccine cocktails. PMID:25200253

  11. Immunotoxicity of aflatoxin B1: impairment of the cell-mediated response to vaccine antigen and modulation of cytokine expression.

    Science.gov (United States)

    Meissonnier, Guylaine M; Pinton, Philippe; Laffitte, Joëlle; Cossalter, Anne-Marie; Gong, Yun Yun; Wild, Christopher P; Bertin, Gérard; Galtier, Pierre; Oswald, Isabelle P

    2008-09-01

    Aflatoxin B1 (AFB1), a mycotoxin produced by Aspergillus flavus or A. parasiticus, is a frequent contaminant of food and feed. This toxin is hepatotoxic and immunotoxic. The present study analyzed in pigs the influence of AFB1 on humoral and cellular responses, and investigated whether the immunomodulation observed is produced through interference with cytokine expression. For 28 days, pigs were fed a control diet or a diet contaminated with 385, 867 or 1807 microg pure AFB1/kg feed. At days 4 and 15, pigs were vaccinated with ovalbumin. AFB1 exposure, confirmed by an observed dose-response in blood aflatoxin-albumin adduct, had no major effect on humoral immunity as measured by plasma concentrations of total IgA, IgG and IgM and of anti-ovalbumin IgG. Toxin exposure did not impair the mitogenic response of lymphocytes but delayed and decreased their specific proliferation in response to the vaccine antigen, suggesting impaired lymphocyte activation in pigs exposed to AFB1. The expression level of pro-inflammatory (TNF-alpha, IL-1beta, IL-6, IFN-gamma) and regulatory (IL-10) cytokines was assessed by real-time PCR in spleen. A significant up-regulation of all 5 cytokines was observed in spleen from pigs exposed to the highest dose of AFB1. In pigs exposed to the medium dose, IL-6 expression was increased and a trend towards increased IFN-gamma and IL-10 was observed. In addition we demonstrate that IL-6 impaired in vitro the antigenic- but not the mitogenic-induced proliferation of lymphocytes from control pigs vaccinated with ovalbumin. These results indicate that AFB1 dietary exposure decreases cell-mediated immunity while inducing an inflammatory response. These impairments in the immune response could participate in failure of vaccination protocols and increased susceptibility to infections described in pigs exposed to AFB1.

  12. Immunotoxicity of aflatoxin B1: Impairment of the cell-mediated response to vaccine antigen and modulation of cytokine expression

    International Nuclear Information System (INIS)

    Aflatoxin B1 (AFB1), a mycotoxin produced by Aspergillus flavus or A. parasiticus, is a frequent contaminant of food and feed. This toxin is hepatotoxic and immunotoxic. The present study analyzed in pigs the influence of AFB1 on humoral and cellular responses, and investigated whether the immunomodulation observed is produced through interference with cytokine expression. For 28 days, pigs were fed a control diet or a diet contaminated with 385, 867 or 1807 μg pure AFB1/kg feed. At days 4 and 15, pigs were vaccinated with ovalbumin. AFB1 exposure, confirmed by an observed dose-response in blood aflatoxin-albumin adduct, had no major effect on humoral immunity as measured by plasma concentrations of total IgA, IgG and IgM and of anti-ovalbumin IgG. Toxin exposure did not impair the mitogenic response of lymphocytes but delayed and decreased their specific proliferation in response to the vaccine antigen, suggesting impaired lymphocyte activation in pigs exposed to AFB1. The expression level of pro-inflammatory (TNF-α, IL-1β, IL-6, IFN-γ) and regulatory (IL-10) cytokines was assessed by real-time PCR in spleen. A significant up-regulation of all 5 cytokines was observed in spleen from pigs exposed to the highest dose of AFB1. In pigs exposed to the medium dose, IL-6 expression was increased and a trend towards increased IFN-γ and IL-10 was observed. In addition we demonstrate that IL-6 impaired in vitro the antigenic- but not the mitogenic-induced proliferation of lymphocytes from control pigs vaccinated with ovalbumin. These results indicate that AFB1 dietary exposure decreases cell-mediated immunity while inducing an inflammatory response. These impairments in the immune response could participate in failure of vaccination protocols and increased susceptibility to infections described in pigs exposed to AFB1

  13. Lipid Nanoparticles with Accessible Nickel as a Vaccine Delivery System for Single and Multiple His-tagged HIV Antigens.

    Science.gov (United States)

    Yan, Weili; Jain, Anekant; O'Carra, Ronan; Woodward, Jerold G; Li, Wenxue; Li, Guanhan; Nath, Avindra; Mumper, Russell J

    2009-07-01

    Lipid-based nanoparticles (NPs) with a small amount of surface-chelated nickel (Ni-NPs) were developed to easily formulate the HIV his-tagged Tat protein, as well as to formulate and co-deliver two HIV antigens (his-p24 and his-Nef) on one particle. Female BALB/c mice were immunized by s.c. injection with his-Tat/Ni-NP formulation (1.5 μg Tat-his/mouse) and control formulations on day 0 and 14. The day 28 anti-Tat specific IgG titer with his-Tat/Ni-NP was significantly greater than that with Alum/his-Tat. Furthermore, splenocytes from his-Tat/Ni-NP immunized mice secreted significantly higher IFN-γ than those from mice immunized with Alum/his-Tat. Although Ni-NPs did not show better adjuvant activity than Tat-coated anionic NPs made with sodium dodecyl sulfate (SDS/NPs), they were less toxic than SDS/NPs. The initial results indicated that co-immunization of mice using his-p24/his-Nef/Ni-NP induced greater antibody response compared to using Alum/his-p24/his-Nef. Co-delivery of two antigens using Ni-NPs also increased the immunogenicity of individual antigens compared to delivery of a single antigen by Ni-NPs. In conclusion, Ni-NPs are an efficient delivery system for HIV vaccines including both single antigen delivery and multiple antigen co-delivery. PMID:21966230

  14. Clinical and immunological evaluation of anti-apoptosis protein, survivin-derived peptide vaccine in phase I clinical study for patients with advanced or recurrent breast cancer

    Directory of Open Access Journals (Sweden)

    Asanuma Hiroko

    2008-05-01

    Full Text Available Abstract Background We previously reported that survivin-2B, a splicing variant of survivin, was expressed in various types of tumors and that survivin-2B peptide might serve as a potent immunogenic cancer vaccine. The objective of this study was to examine the toxicity of and to clinically and immunologically evaluate survivin-2B peptide in a phase I clinical study for patients with advanced or recurrent breast cancer. Methods We set up two protocols. In the first protocol, 10 patients were vaccinated with escalating doses (0.1–1.0 mg of survivin-2B peptide alone 4 times every 2 weeks. In the second protocol, 4 patients were vaccinated with the peptide at a dose of 1.0 mg mixed with IFA 4 times every 2 weeks. Results In the first protocol, no adverse events were observed during or after vaccination. In the second protocol, two patients had induration at the injection site. One patient had general malaise (grade 1, and another had general malaise (grade 1 and fever (grade 1. Peptide vaccination was well tolerated in all patients. In the first protocol, tumor marker levels increased in 8 patients, slightly decreased in 1 patient and were within the normal range during this clinical trial in 1 patient. With regard to tumor size, two patients were considered to have stable disease (SD. Immunologically, in 3 of the 10 patients (30%, an increase of the peptide-specific CTL frequency was detected. In the second protocol, an increase of the peptide-specific CTL frequency was detected in all 4 patients (100%, although there were no significant beneficial clinical responses. ELISPOT assay showed peptide-specific IFN-γ responses in 2 patients in whom the peptide-specific CTL frequency in tetramer staining also was increased in both protocols. Conclusion This phase I clinical study revealed that survivin-2B peptide vaccination was well tolerated. The vaccination with survivin-2B peptide mixed with IFA increased the frequency of peptide-specific CTL more

  15. Designing an efficient multi-epitope peptide vaccine against Vibrio cholerae via combined immunoinformatics and protein interaction based approaches.

    Science.gov (United States)

    Nezafat, Navid; Karimi, Zeinab; Eslami, Mahboobeh; Mohkam, Milad; Zandian, Sanam; Ghasemi, Younes

    2016-06-01

    Cholera continues to be a major global health concern. Among different Vibrio cholerae strains, only O1 and O139 cause acute diarrheal diseases that are related to epidemic and pandemic outbreaks. The currently available cholera vaccines are mainly lived and attenuated vaccines consisting of V. cholerae virulence factors such as toxin-coregulated pili (TCP), outer membrane proteins (Omps), and nontoxic cholera toxin B subunit (CTB). Nowadays, there is a great interest in designing an efficient epitope vaccine against cholera. Epitope vaccines consisting of immunodominant epitopes and adjuvant molecules enhance the possibility of inciting potent protective immunity. In this study, V. cholerae protective antigens (OmpW, OmpU, TcpA and TcpF) and the CTB, which is broadly used as an immunostimulatory adjuvant, were analyzed using different bioinformatics and immunoinformatics tools. The common regions between promiscuous epitopes, binding to various HLA-II supertype alleles, and B-cell epitopes were defined based upon the aforementioned protective antigens. The ultimately selected epitopes and CTB adjuvant were fused together using proper GPGPG linkers to enhance vaccine immunogenicity. A three-dimensional model of the thus constructed vaccine was generated using I-TASSER. The model was structurally validated using the ProSA-web error-detection software and the Ramachandran plot. The validation results indicated that the initial 3D model needed refinement. Subsequently, a high-quality model obtained after various refinement cycles was used for defining conformational B-cell epitopes. Several linear and conformational B-cell epitopes were determined within the epitope vaccine, suggesting likely antibody triggering features of our designed vaccine. Next, molecular docking was performed between the 3D vaccine model and the tertiary structure of the toll like receptor 2 (TLR2). To gain further insight into the interaction between vaccine and TLR2, molecular dynamics

  16. Peptide-beta2-microglobulin-major histocompatibility complex expressing cells are potent antigen-presenting cells that can generate specific T cells.

    Science.gov (United States)

    Obermann, Sonja; Petrykowska, Susanne; Manns, Michael P; Korangy, Firouzeh; Greten, Tim F

    2007-09-01

    Adoptive T-cell therapy represents a promising therapeutic approach for the treatment of cancer. Successful adoptive immunotherapy depends on the ex vivo priming and expansion of antigen-specific T cells. However, the in vitro generation of adequate numbers of functional antigen-specific T cell remains a major obstacle. It is important to develop efficient and reproducible methods to generate high numbers of antigen-specific T cells for adoptive T-cell transfer. We have developed a new artificial antigen-presenting cell (aAPC) by transfection of major histocompatibility (MHC) class I negative Daudi cells with a peptide-beta2-microglobulin-MHC fusion construct (single-chain aAPC) ensuring presentation of the peptide-MHC complex of interest. Using this artificial antigen-presenting cell, we could generate up to 9.2 x 10(8) antigen-specific cytotoxic CD8(+) T cells from 10 ml blood. In vitro generated T cells lysed endogenously presented antigens. Direct comparison of the single-chain aAPC with autologous monocyte-derived dendritic cells demonstrated that these cells were equally efficient in stimulation of T cells. Finally, we were able to generate antigen-specific T cell lines from perpheral blood mononuclear cells of patients receiving cytotoxic chemotherapy. The use of single-chain aAPC represent a promising option for the generation of antigen-specific CD8(+) T cells, which could be used for adoptive T-cell therapy.

  17. Peptide vaccination induces profound changes in the immune system in patients with B-cell chronic lymphocytic leukemia

    Directory of Open Access Journals (Sweden)

    Michael Schmitt

    2011-04-01

    Full Text Available Although the immune status of chronic lymphocytic leukemia (CLL patients is mostly characterized by immunosuppression, there is an accumulation of in vivo (graft-versus-leukemia effect and in vitro (spontaneous remissions after infections data that indicates that CLL might be effectively targeted by T-cell based immunotherapy. Recently, we characterized receptor for hyaluronic acid mediated motility (RHAMM as a preferential target for immunotherapy of CLL. We also completed a RHAMM-derived peptide vaccination phase I/II clinical trial in CLL. Here, we present a detailed immunological analysis of six CLL patients vaccinated with HLA-A2 restricted RHAMM-derived epitope R3 (ILSLELMKL. Beside effective induction of R3-specific cytotoxic T-cells, peptide vaccination caused profound changes in different T-cell subsets as well as cytokines. We present longitudinal analyses of Th17, CD8+CD103+, CD8+CD137+ and IL-17 producing CD8+ T cells (CD8+IL- -17+ as well as important cytokines involved in regulation of immune response such as TGF-β, IL-10, IL-2 and TNF throughout the peptide vaccination period. (Folia Histochemica et Cytobiologica 2011, Vol. 49, No. 1, 161–167

  18. Epitope Mapping of Antigenic MUC1 Peptides to Breast Cancer Antibody Fragment B27.29: A Heteronuclear NMR Study

    Energy Technology Data Exchange (ETDEWEB)

    Grinstead, Jeffrey S.; Schuman, Jason T.; Campbell, Ann P.

    2003-11-13

    MUC1 mucin is a breast cancer-associated transmembrane glycoprotein, of which the extracellular domain is formed by the repeating 20-amino acid sequence GVTSAPDTRPAPGSTAPPAH. In neoplastic breast tissue, the highly immunogenic sequence PDTRPAP (in bold above) is exposed. Antibodies raised directly against MUC1-expressing tumors offer unique access to this neoplastic state, as they represent immunologically relevant ''reverse templates'' of the tumor-associated mucin. In a previous study [Grinstead, J. S., et al. (2002) Biochemistry 41, 9946-9961], 1H NMR methods were used to correlate the effects of cryptic glycosylation outside of the PDTRPAP core epitope sequence on the recognition and binding of Mab B27.29, a monoclonal antibody raised against breast tumor cells. In the study presented here, isotope-edited NMR methods, including 15N and 13C relaxation measurements, were used to probe the recognition and binding of the PDTRPAP epitope sequence to Fab B27.29. Two peptides were studied: a one-repeat MUC1 16mer peptide of the sequence GVTSAPDTRPAPGSTA and a two-repeat MUC1 40mer peptide of the sequence (VTSAPDTRPAPGSTAPPAHG)2. 15N and 13C NMR relaxation parameters were measured for both peptides free in solution and bound to Fab B27.29. The 13CR T1 values best represent changes in the local correlation time of the peptide epitope upon binding antibody, and demonstrate that the PDTRPAP sequence is immobilized in the antibody-combining site. This result is also reflected in the appearance of the 15N- and 13C-edited HSQC spectra, where line broadening of the same peptide epitope resonances is observed. The PDTRPAP peptide epitope expands upon the peptide epitope identified previously in our group as PDTRP by homonuclear NMR experiments [Grinstead, J. S., et al. (2002) Biochemistry 41, 9946-9961], and illustrates the usefulness of the heteronuclear NMR experiments. The implications of these results are discussed within the context of MUC1 breast

  19. Alterations in p53-specific T cells and other lymphocyte subsets in breast cancer patients during vaccination with p53-peptide loaded dendritic cells and low-dose interleukin-2

    DEFF Research Database (Denmark)

    Svane, Inge Marie; Pedersen, Anders E; Nikolajsen, Kirsten;

    2008-01-01

    We have previously established a cancer vaccine using autologous DCs, generated by in vitro stimulation with IL-4 and GM-CSF, and pulsed with six HLA-A*0201 binding wild-type p53 derived peptides. This vaccine was used in combination with low-dose interleukin-2 in a recently published clinical...... Phase II trial where 26 HLA-A2+ patients with progressive late-stage metastatic breast cancer (BC) were included. Almost 1/3rd of the patients obtained stable disease or minor regression during treatment with a positive correlation to tumour over-expression of p53. In the present study, we performed...... a comprehensive analysis of the effector stage of the p53-specific CD8+ T cells by the use of Dextramer Technology and multicolour FACS. Pre- and post-treatment blood samples from eight BC patients were analysed. Independent of clinical outcome p53-specific T cells were phenotypic distinctly antigen experienced...

  20. Hepatitis B surface antigen positivity after twinrix vaccination: a case report.

    Science.gov (United States)

    Lee, Yirang; Kim, Jae-Seok; Park, Ji-Young; Kim, Soo Young; Hwang, In Hong; Cho, Hyoun Chan

    2014-01-01

    Travelers might have an increased risk of hepatitis B virus (HBV) infection. We report a case of prolonged transient hepatitis B surface antigenemia in a healthy Canadian female 8 days after administration of a combined hepatitis A and hepatitis B vaccine. Travel health providers providing hepatitis B vaccines need to be aware of this phenomenon and educate their patients accordingly. PMID:24861218

  1. Antigen design enhances the immunogenicity of Semliki Forest virus-based therapeutic human papillomavirus vaccines

    NARCIS (Netherlands)

    Ip, P. P.; Boerma, A.; Walczak, M.; Oosterhuis, K.; Haanen, J. B.; Schumacher, T. N.; Nijman, H. W.; Daemen, T.

    2015-01-01

    Cellular immunity against cancer can be achieved with viral vector-and DNA-based immunizations. In preclinical studies, cancer vaccines are very potent, but in clinical trials these potencies are not achieved yet. Thus, a rational approach to improve cancer vaccines is warranted. We previously demon

  2. Synthetic Self-Adjuvanting Glycopeptide Cancer Vaccines

    Science.gov (United States)

    Payne, Richard; McDonald, David; Byrne, Scott

    2015-10-01

    Due to changes in glycosyltransferase expression during tumorigenesis, the glycoproteins of cancer cells often carry highly truncated carbohydrate chains compared to those on healthy cells. These glycans are known as tumor-associated carbohydrate antigens, and are prime targets for use in vaccines for the prevention and treatment of cancer. Herein, we review the state-of-the-art in targeting the immune system towards tumor-associated glycopeptide antigens via synthetic self adjuvanting vaccines, in which the antigenic and adjuvanting moieties of the vaccines are present in the same molecule. The majority of the self-adjuvanting glycopeptide cancer vaccines reported to date employ antigens from mucin 1, a protein which is highly over-expressed and aberrantly glycosylated in many forms of cancer. The adjuvants used in these vaccines predominantly include lipopeptide- or lipoamino acid-based TLR2 agonists, although studies investigating stimulation of TLR9 and TLR4 are also discussed. Most of these adjuvants are highly lipophilic, and, upon conjugation to antigenic peptides, provide amphiphilic vaccine molecules. The amphiphilic nature of these vaccine constructs can lead to the formation of higher-order structures by vaccines in solution, which are likely to be important for their efficacy in vivo.

  3. Size-exclusion HPLC provides a simple, rapid, and versatile alternative method for quality control of vaccines by characterizing the assembly of antigens.

    Science.gov (United States)

    Yang, Yanli; Li, Hao; Li, Zhengjun; Zhang, Yan; Zhang, Songping; Chen, Yi; Yu, Mengran; Ma, Guanghui; Su, Zhiguo

    2015-02-25

    The assembly of antigen structure is often crucial to the potency of vaccines. Currently adopted methods like animal testing and ultracentrifugation take long time and are difficult to automate for multiple samples. Here we develop a size-exclusion high-performance liquid chromatography (SE-HPLC) method to characterize the assembly of antigen structure during both manufacturing process and storage. Three important vaccine antigens including inactivated foot and mouth disease virus (FMDV), which is a virus vaccine; and two virus-like particles (VLPs) vaccines involving hepatitis B core antigen (HBcAg) VLPs, and hepatitis B surface antigen (HBsAg) VLPs, were successfully analyzed using commercially available TSK gel columns with pore size above 45nm. Combined with other analytical methods including SDS-PAGE, dynamic light scattering, wavelength scan, and multi-angle laser light scattering, the SE-HPLC method was proven to be a simple, rapid, and reliable tool for antigen particles assembly analysis. Specifically, for FMDV whole virus particle, SE-HPLC was used to analyze 146S content in vaccine preparations and the thermal dissociation of the 146S. For HBcAg-VLPs that are expressed in recombinant Escherichia coli, its expression level during cell culture process was quantitatively monitored by SE-HPLC. The SE-HPLC also showed applicability for quality check of HBsAg vaccine preparations by monitoring the product consistency of different lot number and the product stability during storage. Results shown in this work clearly demonstrated that SE-HPLC method has potential as a versatile alternative technology for control of the final product by both manufacturers and the regulatory agencies. PMID:25604799

  4. Size-exclusion HPLC provides a simple, rapid, and versatile alternative method for quality control of vaccines by characterizing the assembly of antigens.

    Science.gov (United States)

    Yang, Yanli; Li, Hao; Li, Zhengjun; Zhang, Yan; Zhang, Songping; Chen, Yi; Yu, Mengran; Ma, Guanghui; Su, Zhiguo

    2015-02-25

    The assembly of antigen structure is often crucial to the potency of vaccines. Currently adopted methods like animal testing and ultracentrifugation take long time and are difficult to automate for multiple samples. Here we develop a size-exclusion high-performance liquid chromatography (SE-HPLC) method to characterize the assembly of antigen structure during both manufacturing process and storage. Three important vaccine antigens including inactivated foot and mouth disease virus (FMDV), which is a virus vaccine; and two virus-like particles (VLPs) vaccines involving hepatitis B core antigen (HBcAg) VLPs, and hepatitis B surface antigen (HBsAg) VLPs, were successfully analyzed using commercially available TSK gel columns with pore size above 45nm. Combined with other analytical methods including SDS-PAGE, dynamic light scattering, wavelength scan, and multi-angle laser light scattering, the SE-HPLC method was proven to be a simple, rapid, and reliable tool for antigen particles assembly analysis. Specifically, for FMDV whole virus particle, SE-HPLC was used to analyze 146S content in vaccine preparations and the thermal dissociation of the 146S. For HBcAg-VLPs that are expressed in recombinant Escherichia coli, its expression level during cell culture process was quantitatively monitored by SE-HPLC. The SE-HPLC also showed applicability for quality check of HBsAg vaccine preparations by monitoring the product consistency of different lot number and the product stability during storage. Results shown in this work clearly demonstrated that SE-HPLC method has potential as a versatile alternative technology for control of the final product by both manufacturers and the regulatory agencies.

  5. The effect of different adjuvants on immune parameters and protection following vaccination of sheep with a larval-specific antigen of the gastrointestinal nematode, Haemonchus contortus.

    Directory of Open Access Journals (Sweden)

    David Piedrafita

    Full Text Available It has recently been recognised that vaccine adjuvants play a critical role in directing the nature of a vaccine induced effector response. In the present study, several adjuvants were evaluated for their ability to protect sheep after field vaccination with the larval-specific Haemonchus contortus antigen, HcsL3. Using a suboptimal antigen dose, aluminium adjuvant was shown to reduce the cumulative faecal egg counts (cFEC and worm burden by 23% and 25% respectively, in agreement with a previous study. The addition of Quil A to the aluminium-adjuvanted vaccine brought cFEC back to control levels. Vaccination with the adjuvant DEAE-dextran almost doubled the protection compared to the aluminium-adjuvanted vaccine resulting in 40% and 41% reduction in cFEC and worm counts compared to controls. Examination of skin responses following i.d. injection of exsheathed L3, revealed that cFEC was negatively correlated with wheal size and tissue eosinophils for the DEAE-dextran and aluminium-adjuvanted groups respectively. These studies have for the first time shown the potential of DEAE-dextran adjuvant for helminth vaccines, and discovered significant cellular correlates of vaccine-induced protection.

  6. Comparison of polystyrene nanoparticles and UV-inactivated antigen-displaying adenovirus for vaccine delivery in mice

    Science.gov (United States)

    2013-01-01

    Background Inert nanoparticles are attracting attention as carriers for protein-based vaccines. Here we evaluate the immunogenicity of the model antigen ovalbumin delivered on polystyrene particles and directly compare particulate delivery with adenovirus-based immunization. Findings Mice were vaccinated with soluble ovalbumin, ovalbumin-coated polystyrene particles of different sizes, or an adenovirus-based expression-display vector that encodes and displays a pIX-ovalbumin fusion protein. Antibody responses were clearly higher when ovalbumin was administered on polystyrene particles compared to soluble protein administration, regardless of the particle size. Compared to adenovirus-based immunization, antibody levels were lower if an equivalent amount of protein was delivered, and no cellular immune response was detectable. Conclusions We demonstrate in a side-by-side comparison that inert nanoparticles allow for the reduction of the administered antigen amount compared to immunization with soluble protein and induce strongly enhanced antibody responses, but responses are lower compared to adenovirus-based immunization. PMID:23560981

  7. Reduced-antigen, combined diphtheria, tetanus and acellular pertussis vaccine, adsorbed (Boostrix®): a review of its properties and use as a single-dose booster immunization.

    Science.gov (United States)

    McCormack, Paul L

    2012-09-10

    Reduced-antigen, combined diphtheria, tetanus and three-component acellular pertussis vaccine (Tdap; Boostrix®) is indicated for booster vaccination against diphtheria, tetanus and pertussis in individuals from age four years onwards in Europe and from age 10 years onwards in the US. Compared with infant formulations used for primary vaccination, Tdap contains reduced quantities (10-50%) of all toxoids and antigens, which are adsorbed to either ≤0.39 mg/dose (US licensed formulation) or 0.5 mg/dose (rest-of-world formulation) of aluminium adjuvant. The reduced antigen content is designed to avoid the increasing reactogenicity historically seen with the fourth and fifth doses of infant vaccine. This article reviews the immunogenicity, protective efficacy and reactogenicity of Tdap booster administered to children, adolescents and adults, including those aged ≥65 years. In clinical trials, a single booster dose of Tdap induced seroprotective levels of antibodies to diphtheria and tetanus toxoids in virtually all children and adolescents, and in a high proportion of adults and elderly individuals at approximately 1 month post-vaccination irrespective of their vaccination history. In all age groups, seropositivity rates for antibodies against pertussis antigens were ≥90% (including in unvaccinated adolescents), and booster response rates were high. Tdap was safely co-administered with other common vaccines without significantly affecting the immune responses. The immunogenicity and reactogenicity profiles of booster doses of Tdap were generally similar to those of infant diphtheria-tetanus-whole-cell pertussis vaccine and infant diphtheria-tetanus-acellular pertussis vaccine in children aged 4-6 years, and infant diphtheria-tetanus vaccine in older children. In adolescents and adults, the immunogenicity and reactogenicity of Tdap were generally similar to those of reduced-antigen diphtheria-tetanus vaccine, reduced-antigen diphtheria

  8. Immunological Correlates for Protection against Intranasal Challenge of Bacillus anthracis Spores Conferred by a Protective Antigen-Based Vaccine in Rabbits

    OpenAIRE

    Weiss, Shay; Kobiler, David; Levy, Haim; Marcus, Hadar; Pass, Avi; Rothschild, Nili; Altboum, Zeev

    2006-01-01

    Correlates between immunological parameters and protection against Bacillus anthracis infection in animals vaccinated with protective antigen (PA)-based vaccines could provide surrogate markers to evaluate the putative protective efficiency of immunization in humans. In previous studies we demonstrated that neutralizing antibody levels serve as correlates for protection in guinea pigs (S. Reuveny et al., Infect. Immun. 69:2888-2893, 2001; H. Marcus et al., Infect. Immun. 72:3471-3477, 2004). ...

  9. Combining Viral Vectored and Protein-in-adjuvant Vaccines Against the Blood-stage Malaria Antigen AMA1: Report on a Phase 1a Clinical Trial

    OpenAIRE

    Susanne H. Hodgson; Choudhary, Prateek; Elias, Sean C; Milne, Kathryn H; Thomas W Rampling; Biswas, Sumi; Ian D Poulton; Miura, Kazutoyo; Douglas, Alexander D.; Alanine, Daniel GW; Illingworth, Joseph J.; de Cassan, Simone C.; ZHU, DAMING; Nicosia, Alfredo; Long, Carole A.

    2014-01-01

    The development of effective vaccines against difficult disease targets will require the identification of new subunit vaccination strategies that can induce and maintain effective immune responses in humans. Here we report on a phase 1a clinical trial using the AMA1 antigen from the blood-stage Plasmodium falciparum malaria parasite delivered either as recombinant protein formulated with Alhydrogel adjuvant with and without CPG 7909, or using recombinant vectored vaccines—chimpanzee adenovir...

  10. Induction of Immune Tolerance in Asthmatic Mice by Vaccination with DNA Encoding an Allergen–Cytotoxic T Lymphocyte-Associated Antigen 4 Combination ▿

    OpenAIRE

    Zhang, Fang; Huang, Gang; Hu, Bo; Song, Yong; Shi, Yi

    2011-01-01

    Allergen-specific immunotherapy is a potential treatment for allergic diseases. We constructed an allergen–cytotoxic T lymphocyte-associated antigen 4 (CTLA-4)-encoding DNA vaccine, administered it directly to antigen-presenting cells (APCs), and investigated its ability and mechanisms to ameliorate allergic airway inflammation in an asthmatic mouse model. An allergen-CTLA-4 DNA plasmid (OVA-CTLA-4-pcDNA3.1) encoding an ovalbumin (OVA) and the mouse CTLA-4 extracellular domain was constructed...

  11. Comparison of BCG, MPL and cationic liposome adjuvant systems in leishmanial antigen vaccine formulations against murine visceral leishmaniasis

    Directory of Open Access Journals (Sweden)

    Bhowmick Sudipta

    2010-06-01

    Full Text Available Abstract Background The development of an effective vaccine against visceral leishmaniasis (VL caused by Leishmania donovani is an essential aim for controlling the disease. Use of the right adjuvant is of fundamental importance in vaccine formulations for generation of effective cell-mediated immune response. Earlier we reported the protective efficacy of cationic liposome-associated L. donovani promastigote antigens (LAg against experimental VL. The aim of the present study was to compare the effectiveness of two very promising adjuvants, Bacille Calmette-Guerin (BCG and Monophosphoryl lipid A (MPL plus trehalose dicorynomycolate (TDM with cationic liposomes, in combination with LAg, to confer protection against murine VL. Results All the three formulations afforded significant protection against L. donovani in both the visceral organs, liver and spleen. Although comparable level of protection was observed in BCG+LAg and MPL-TDM+LAg immunized mice, highest level of protection was exhibited by the liposomal LAg immunized group. Significant increase in anti-LAg IgG levels were detected in both MPL-TDM+LAg and liposomal LAg immunized animals with higher levels of IgG2a than IgG1. But BCG+LAg failed to induce any antibody response. As an index of cell-mediated immunity DTH responses were measured and significant response was observed in mice vaccinated with all the three different formulations. However, highest responses were observed with liposomal vaccine immunization. Comparative evaluation of IFN-γ and IL-4 responses in immunized mice revealed that MPL-TDM+LAg group produced the highest level of IFN-γ but lowest IL-4 level, while BCG+LAg demonstrated generation of suboptimum levels of both IFN-γ and IL-4 response. Elicitation of moderate levels of prechallenge IFN-γ along with optimum IL-4 corresponds with successful vaccination with liposomal LAg. Conclusion This comparative study reveals greater effectiveness of the liposomal vaccine fo