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Sample records for cell-restricted antigen presentation

  1. Harnessing Dendritic Cells for Tumor Antigen Presentation

    International Nuclear Information System (INIS)

    Dendritic cells (DC) are professional antigen presenting cells that are crucial for the induction of anti-tumor T cell responses. As a consequence, research has focused on the harnessing of DCs for therapeutic interventions. Although current strategies employing ex vivo-generated and tumor-antigen loaded DCs have been proven feasible, there are still many obstacles to overcome in order to improve clinical trial successes and offset the cost and complexity of customized cell therapy. This review focuses on one of these obstacles and a pivotal step for the priming of tumor-specific CD8+ and CD4+ T cells; the in vitro loading of DCs with tumor antigens

  2. Harnessing Dendritic Cells for Tumor Antigen Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Nierkens, Stefan [Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Geert Grooteplein 28, Nijmegen 6525 GA (Netherlands); Janssen, Edith M., E-mail: edith.janssen@cchmc.org [Division of Molecular Immunology, Cincinnati Children' s Hospital Research Foundation, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229 (United States)

    2011-04-26

    Dendritic cells (DC) are professional antigen presenting cells that are crucial for the induction of anti-tumor T cell responses. As a consequence, research has focused on the harnessing of DCs for therapeutic interventions. Although current strategies employing ex vivo-generated and tumor-antigen loaded DCs have been proven feasible, there are still many obstacles to overcome in order to improve clinical trial successes and offset the cost and complexity of customized cell therapy. This review focuses on one of these obstacles and a pivotal step for the priming of tumor-specific CD8{sup +} and CD4{sup +} T cells; the in vitro loading of DCs with tumor antigens.

  3. MHC Class Ⅰ Antigen Presentation- Recently Trimmed and Well Presented

    Institute of Scientific and Technical Information of China (English)

    Barry Flutter; Bin Gao

    2004-01-01

    Presentation of antigenic peptide to T cells by major histocompatibility complex (MHC) class Ⅰ molecules is the key to the cellular immune response. Non-self intracellular proteins are processed into short peptides and transported into endoplasmic reticulum (ER) where they are assembled with class Ⅰ molecules assisted by several chaperone proteins to form trimeric complex. MHC class Ⅰ complex loaded with optimised peptides travels to the cell surface of antigen presentation cells to be recognised by T cells. The cells presenting non-self peptides are cleared by CD8 positive T cells. In order to ensure that T cells detect an infection or mutation within the target cells the process of peptide loading and class Ⅰ expression must be carefully regulated. Many of the cellular components involved in antigen processing and class Ⅰ presentation are known and their various functions are now becoming clearer. Cellular & Molecular Immunology. 2004;1(1):22-30.

  4. MHC Class I Antigen Presentation- Recently Trimmed and Well Presented

    Institute of Scientific and Technical Information of China (English)

    BarryFlutter; BinGao

    2004-01-01

    Presentation of antigenic peptide to T cells by major histocompatibility complex (MHC) class I molecules is the key to the cellular immune response. Non-self intracellular proteins are processed into short peptides and transported into endoplasmic reticulum (ER) where they are assembled with class I molecules assisted by several chaperone proteins to form trimeric complex. MHC class I complex loaded with optimised peptides travels to the cell surface of antigen presentation cells to be recognised by T cells. The cells presenting non-self peptides are cleared by CD8 positive T cells. In order to ensure that T cells detect an infection or mutation within the target cells the process of peptide loading and class I expression must be carefully regulated. Many of the cellular components involved in antigen processing and class I presentation are known and their various functions are now becoming clearer. Cellular & Molecular Immunology. 2004;1(1):22-30.

  5. MYELIN ANTIGEN LOAD INFLUENCES ANTIGEN PRESENTATION AND SEVERITY OF CENTRAL NERVOUS SYSTEM AUTOIMMUNITY

    OpenAIRE

    Jaini, Ritika; Popescu, Daniela C.; Flask, Chris A.; Macklin, Wendy B.; Tuohy, Vincent K.

    2013-01-01

    This study was designed to understand the impact of self-antigen load on manifestation of organ specific autoimmunity. Using a transgenic mouse model characterized by CNS hypermyelination, we show that larger myelin content results in greater severity of experimental autoimmune encephalomyelitis attributable to an increased number of microglia within the hypermyelinated brain. We conclude that a larger self-antigen load affects an increase in number of tissue resident antigen presenting cells...

  6. Dendritic cell function and antigen presentation in malaria.

    Science.gov (United States)

    Cockburn, Ian A; Zavala, Fidel

    2016-06-01

    Due to the diverse roles T cells play in protection against malaria as well as pathogenesis it is critical to know which cells present antigen and the nature of the antigens they present. During pre-erythrocytic stages of infection, cutting-edge imaging studies have shown how Plasmodium antigens are presented during both the priming and effector phases of the protective CD8+ T cell response. During blood stages, pathology is in part due to the loss of DC function and the action of pathogenic T cells in the brain. Recently endothelial cells presenting malaria antigen to cognate T cells have emerged as critical players in malaria pathogenesis. Manipulating these processes may inform both vaccine design and the development of therapies for cerebral malaria. PMID:26845735

  7. Lipid peroxidation causes endosomal antigen release for cross-presentation.

    Science.gov (United States)

    Dingjan, Ilse; Verboogen, Daniëlle Rj; Paardekooper, Laurent M; Revelo, Natalia H; Sittig, Simone P; Visser, Linda J; Mollard, Gabriele Fischer von; Henriet, Stefanie Sv; Figdor, Carl G; Ter Beest, Martin; van den Bogaart, Geert

    2016-01-01

    Dendritic cells (DCs) present foreign antigen in major histocompatibility complex (MHC) class I molecules to cytotoxic T cells in a process called cross-presentation. An important step in this process is the release of antigen from the lumen of endosomes into the cytosol, but the mechanism of this step is still unclear. In this study, we show that reactive oxygen species (ROS) produced by the NADPH-oxidase complex NOX2 cause lipid peroxidation, a membrane disrupting chain-reaction, which in turn results in antigen leakage from endosomes. Antigen leakage and cross-presentation were inhibited by blocking ROS production or scavenging radicals and induced when using a ROS-generating photosensitizer. Endosomal antigen release was impaired in DCs from chronic granulomatous disease (CGD) patients with dysfunctional NOX2. Thus, NOX2 induces antigen release from endosomes for cross-presentation by direct oxidation of endosomal lipids. This constitutes a new cellular function for ROS in regulating immune responses against pathogens and cancer. PMID:26907999

  8. ONCOLYTIC VIRUS-MEDIATED REVERSAL OF IMPAIRED TUMOR ANTIGEN PRESENTATION

    Directory of Open Access Journals (Sweden)

    Shashi Ashok Gujar

    2014-04-01

    Full Text Available Anti-tumor immunity can eliminate existing cancer cells and also maintain a constant surveillance against possible relapse. Such an antigen-specific adaptive response begins when tumor-specific T cells become activated. T cell activation requires two signals on antigen presenting cells (APCs: antigen presentation through MHC molecules and co-stimulation. In the absence of one or both of these signals, T cells remain inactivated or can even become tolerized. Cancer cells and their associated microenvironment strategically hinder the processing and presentation of tumor antigens and consequently prevent the development of anti-tumor immunity. Many studies, however, demonstrate that interventions that overturn tumor-associated immune evasion mechanisms can establish anti-tumor immune responses of therapeutic potential. One such intervention is oncolytic virus (OV-based anti-cancer therapy. Here we discuss how OV-induced immunological events override tumor-associated antigen presentation impairment and promote appropriate T cell:APC interaction. Detailed understanding of this phenomenon is pivotal for devising the strategies that will enhance the efficacy of OV-based anti-cancer therapy by complementing its inherent oncolytic

  9. The role of FcRn in antigen presentation

    Directory of Open Access Journals (Sweden)

    Kristi eBaker

    2014-08-01

    Full Text Available Immunoglobulins are unique molecules capable of simultaneously recognizing a diverse array of antigens and themselves being recognized by a broad array of receptors. The abundance specifically of the IgG subclass and the variety of signaling receptors to which it binds render this an important immunomodulatory molecule. In addition to the classical Fcγ receptors (FcγR which bind IgG at the cell surface, the neonatal Fc receptor (FcRn is a lifelong resident of the endolysosomal system of most hematopoietic cells where it determines the intracellular fate of both IgG and IgG-containing immune complexes (IgG IC. Crosslinking of FcRn by multivalent IgG IC within antigen presenting cells such as dendritic cells (DC initiates specific mechanisms which result in trafficking of the antigen-bearing IgG IC into compartments from which the antigen can successfully be processed into peptide epitopes compatible with loading onto both MHC class I and II molecules. In turn, this enables the synchronous activation of both CD4+ and CD8+ T cell responses against the cognate antigen, thereby bridging the gap between the humoral and cellular branches of the adaptive immune response. Critically, FcRn-driven T cell priming is efficient at very low doses of antigen due to the exquisite sensitivity of the IgG-mediated antigen delivery system through which it operates. FcRn-mediated antigen presentation has important consequences in tissue compartments replete with IgG and serves not only to determine homeostatic immune activation at a variety of sites but also to induce inflammatory responses upon exposure to antigens perceived as foreign. Therapeutically targeting the pathway by which FcRn enables T cell activation in response to IgG IC is thus a highly attractive prospect not only for the treatment of diseases that are driven by immune complexes but also for manipulating local immune responses against defined antigens such as those present during infections and

  10. Photoaffinity labeling demonstrates binding between Ia and antigen on antigen-presenting cells

    International Nuclear Information System (INIS)

    Antigen-presenting cells (APCs) bind and present antigens to immunocompetent T lymphocytes in the context of Ia molecules: however, the molecular nature of the immunogenic complexes on the surface of these cells is unknown. They have used radioiodinated photoreactive Beef insulin (BI) derivatized in the B29 position with (n-[4-(4'-azido-3'-[125]iodophenylazo)benzoyl]-3-aminopropyl-n-oxy-succinimide) (B29-AZAP) as antigen to examine the nature of these molecular complexes. The probe was reacted with either of two B hybridoma APCs, TA3 (Ia/sup k/d/) and LB(Ia/sup d/b/) which present insulin on I-A/sup d/ and I-A/sub b/ respectively, to appropriately restricted, BI specific T helper lymphocytes (T/sub H/). Samples were photolyzed, solubilized and then analyzed by SDS-PAGE. Two protein bands of 36-kDa and 27-kDa were specifically labeled on TA3 and LB cells. Treatment of these bands with dithiothreitol or endo-N-β-glycosidase F demonstrates that each is composed of a single glycoprotein. These bands are immunoprecipitable with haplotype specific but not control anti-Ia antibodies. This identifies the labeled bands as the α- and β- subunits of class II MHC antigens. They conclude that a molecular complex may form between Ia and antigen on APCs and that formation of this complex does not require the presence of an antigen specific T/sub H/ cell receptor

  11. Carbohydrate-functionalized nanovaccines preserve HIV-1 antigen stability and activate antigen presenting cells.

    Science.gov (United States)

    Vela Ramirez, J E; Roychoudhury, R; Habte, H H; Cho, M W; Pohl, N L B; Narasimhan, B

    2014-01-01

    The functionalization of polymeric nanoparticles with ligands that target specific receptors on immune cells offers the opportunity to tailor adjuvant properties by conferring pathogen mimicking attributes to the particles. Polyanhydride nanoparticles are promising vaccine adjuvants with desirable characteristics such as immunomodulation, sustained antigen release, activation of antigen presenting cells (APCs), and stabilization of protein antigens. These capabilities can be exploited to design nanovaccines against viral pathogens, such as HIV-1, due to the important role of dendritic cells (DCs) and macrophages in viral spread. In this work, an optimized process was developed for carbohydrate functionalization of HIV-1 antigen-loaded polyanhydride nanoparticles. The carbohydrate-functionalized nanoparticles preserved antigenic properties upon release and also enabled sustained antigen release kinetics. Particle internalization was observed to be chemistry-dependent with positively charged nanoparticles being taken up more efficiently by DCs. Up-regulation of the activation makers CD40 and CD206 was demonstrated with carboxymethyl-α-d-mannopyranosyl-(1,2)-d-mannopyranoside functionalized nanoparticles. The secretion of the cytokines IL-6 and TNF-α was shown to be chemistry-dependent upon stimulation with carbohydrate-functionalized nanoparticles. These results offer important new insights upon the interactions between carbohydrate-functionalized nanoparticles and APCs and provide foundational information for the rational design of targeted nanovaccines against HIV-1. PMID:25068589

  12. Neutrophil elastase enhances antigen presentation by upregulating human leukocyte antigen class I expression on tumor cells.

    Science.gov (United States)

    Chawla, Akhil; Alatrash, Gheath; Philips, Anne V; Qiao, Na; Sukhumalchandra, Pariya; Kerros, Celine; Diaconu, Iulia; Gall, Victor; Neal, Samantha; Peters, Haley L; Clise-Dwyer, Karen; Molldrem, Jeffrey J; Mittendorf, Elizabeth A

    2016-06-01

    Neutrophil elastase (NE) is an innate immune cell-derived inflammatory mediator that we have shown increases the presentation of tumor-associated peptide antigens in breast cancer. In this study, we extend these observations to show that NE uptake has a broad effect on enhancing antigen presentation by breast cancer cells. We show that NE increases human leukocyte antigen (HLA) class I expression on the surface of breast cancer cells in a concentration and time-dependent manner. HLA class I upregulation requires internalization of enzymatically active NE. Western blots of NE-treated breast cancer cells confirm that the expression of total HLA class I as well as the antigen-processing machinery proteins TAP1, LMP2, and calnexin does not change following NE treatment. This suggests that NE does not increase the efficiency of antigen processing; rather, it mediates the upregulation of HLA class I by stabilizing and reducing membrane recycling of HLA class I molecules. Furthermore, the effects of NE extend beyond breast cancer since the uptake of NE by EBV-LCL increases the presentation of HLA class I-restricted viral peptides, as shown by their increased sensitivity to lysis by EBV-specific CD8+ T cells. Together, our results show that NE uptake increases the responsiveness of breast cancer cells to adaptive immunity by broad upregulation of membrane HLA class I and support the conclusion that the innate inflammatory mediator NE enhances tumor cell recognition and increases tumor sensitivity to the host adaptive immune response. PMID:27129972

  13. Photoaffinity labeling demonstrates binding between Ia molecules and nominal antigen on antigen-presenting cells.

    OpenAIRE

    Phillips, M L; Yip, C C; Shevach, E M; Delovitch, T L

    1986-01-01

    We have used radioiodinated photoreactive bovine insulin as antigen to examine the molecular nature of immunogenic complexes that form on antigen-presenting cells. The probe was allowed to bind to either insulin-presenting B-hybridoma cells, lipopolysaccharide-stimulated blasts, or bovine insulin-specific helper-T-hybridoma cells in the dark. Samples were then exposed to light to induce crosslinkage, solubilized, and analyzed by gel electrophoresis. Two protein bands at about 36 kDa and 27 kD...

  14. Defective antigen-presenting cell function in human neonates

    OpenAIRE

    Velilla, Paula A.; Rugeles, Maria T.; Chougnet, Claire A.

    2006-01-01

    Immaturity of the immune system has been suggested as an underlying factor for the high rate of morbidity and mortality from infections in newborns. Functional impairment of neonatal T cells is frequently quoted as the main underlying mechanism for such immaturity. However, recent studies suggest that neonatal antigen-presenting cells (APCs) also exhibit functional alterations, which could lead to secondary defects of adaptive T cell responses. In this review, we summarize what is known on th...

  15. Bone marrow-derived thymic antigen-presenting cells determine self-recognition of Ia-restricted T lymphocytes

    International Nuclear Information System (INIS)

    The authors previously have demonstrated that in radiation-induced bone marrow chimeras, T-cell self-Ia restriction specificity appeared to correlate with the phenotype of the bone marrow-derived antigen-presenting (or dendritic) cell in the thymus during T-cell development. However, these correlations were necessarily indirect because of the difficulty in assaying thymic function directly by adult thymus transplant, which has in the past been uniformly unsuccessful. They now report success in obtaining functional T cells from nude mice grafted with adult thymuses reduced in size by treatment of the thymus donor with anti-thymocyte globulin and cortisone. When (B10 Scn X B10.D2)F1 nude mice (I-Ab,d) are given parental B10.D2 (I-Ad) thymus grafts subcutaneously, their T cells are restricted to antigen recognition in association with I-Ad gene products but not I-Ab gene products. Furthermore, thymuses from (B10 X B10.D2)F1 (I-Ab,d)----B10 (I-Ab) chimeras transplanted 6 months or longer after radiation (a time at which antigen-presenting cell function is of donor bone marrow phenotype) into (B10 X B10.D2)F1 nude mice generate T cells restricted to antigen recognition in association with both I-Ad and I-Ab gene products. Thymuses from totally allogeneic bone marrow chimeras appear to generate T cells of bone marrow donor and thymic host restriction specificity. Thus, when thymus donors are radiation-induced bone marrow chimeras, the T-cell I-region restriction of the nude mice recipients is determined at least in part by the phenotype of the bone marrow-derived thymic antigen presenting cells or dendritic cells in the chimeric thymus

  16. Identification of a peptide binding protein that plays a role in antigen presentation.

    OpenAIRE

    Lakey, E K; Margoliash, E.; Pierce, S K

    1987-01-01

    The helper T-cell response to globular proteins appears, in general, to require intracellular processing of the antigen, such that a peptide fragment containing the T-cell antigenic determinant is released and transported to and held on the surface of an Ia-expressing, antigen-presenting cell. However, the molecular details underlying these phenomena are largely unknown. The means by which antigenic peptides are anchored on the antigen-presenting cell surface was investigated. A cell surface ...

  17. A role for NADPH oxidase in antigen presentation

    Directory of Open Access Journals (Sweden)

    Gail J Gardiner

    2013-09-01

    Full Text Available The nicotinamide adenine dinucleotide phosphate (NADPH oxidase expressed in phagocytes is a multi-subunit enzyme complex that generates superoxide (O2.-. This radical is an important precursor of hydrogen peroxide (H2O2 and other reactive oxygen species (ROS needed for microbicidal activity during innate immune responses. Inherited defects in NADPH oxidase give rise to chronic granulomatous disease (CGD, a primary immunodeficiency characterized by recurrent infections and granulomatous inflammation. Interestingly, CGD, CGD carrier status, and oxidase gene polymorphisms have all been associated with autoinflammatory and autoimmune disorders, suggesting a potential role for NADPH oxidase in regulating adaptive immune responses. Here, NADPH oxidase function in antigen processing and presentation is reviewed. NADPH oxidase influences dendritic cell (DC crosspresentation by major histocompatibility complex class I molecules (MHC-I through regulation of the phagosomal microenvironment, while in B lymphocytes, NADPH oxidase alters epitope selection by major histocompatibility complex class II molecules (MHC-II.

  18. Human leukocyte antigen-DO regulates surface presentation of human leukocyte antigen class II-restricted antigens on B cell malignancies

    NARCIS (Netherlands)

    Kremer, A.N.; Meijden, E.D. van der; Honders, M.W.; Pont, M.J.; Goeman, J.J.; Falkenburg, J.H.F.; Griffioen, M.

    2014-01-01

    Hematological malignancies often express surface HLA class II, making them attractive targets for CD4+ T cell therapy. We previously demonstrated that HLA class II ligands can be divided into DM-resistant and DM-sensitive antigens. In contrast to presentation of DM-resistant antigens, presentation o

  19. Stratification of Antigen-presenting Cells within the Normal Cornea

    Directory of Open Access Journals (Sweden)

    Jared E. Knickelbein

    2009-11-01

    Full Text Available The composition and location of professional antigen presenting cells (APC varies in different mucosal surfaces. The cornea, long considered an immune-privileged tissue devoid of APCs, is now known to host a heterogeneous network of bone marrow-derived cells. Here, we utilized transgenic mice that express enhanced green fluorescent protein (EGFP from the CD11c promoter (pCD11c in conjunction with immunohistochemical staining to demonstrate an interesting stratification of APCs within non-inflamed murine corneas. pCD11c+ dendritic cells (DCs reside in the basal epithelium, seemingly embedded in the basement membrane. Most DCs express MHC class II on at least some dendrites, which extend up to 50 µm in length and traverse up 20 µm tangentially towards the apical surface of the epithelium. The DC density diminishes from peripheral to central cornea. Beneath the DCs and adjacent to the stromal side of the basement membrane reside pCD11c-CD11b+ putative macrophages that express low levels of MHC class II. Finally, MHC class IIpCD11c-CD11b+ cells form a network throughout the remainder of the stroma. This highly reproducible stratification of bone marrow-derived cells is suggestive of a progression from an APC function at the exposed corneal surface to an innate immune barrier function deeper in the stroma.

  20. Regulation of antigen presentation by acidic pH

    OpenAIRE

    1990-01-01

    The effect of pH on functional association of peptide antigens with APC membranes was investigated by using aldehyde-fixed B cells and class II- restricted T cell hybridomas to assess antigen/MHC complex formation. The results indicated that the rate and extent of functional peptide binding was markedly increased at pH 5.0 as compared with pH 7.3. The pH dependence of binding was preserved after pretreatment of fixed APC with pH 5.0 buffer, suggesting that pH had a direct effect on the intera...

  1. Distribution of primed T cells and antigen-loaded antigen presenting cells following intranasal immunization in mice.

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    Annalisa Ciabattini

    Full Text Available Priming of T cells is a key event in vaccination, since it bears a decisive influence on the type and magnitude of the immune response. T-cell priming after mucosal immunization via the nasal route was studied by investigating the distribution of antigen-loaded antigen presenting cells (APCs and primed antigen-specific T cells. Nasal immunization studies were conducted using the model protein antigen ovalbumin (OVA plus CpG oligodeoxynucleotide adjuvant. Trafficking of antigen-specific primed T cells was analyzed in vivo after adoptive transfer of OVA-specific transgenic T cells in the presence or absence of fingolimod, a drug that causes lymphocytes sequestration within lymph nodes. Antigen-loaded APCs were observed in mediastinal lymph nodes, draining the respiratory tract, but not in distal lymph nodes. Antigen-specific proliferating T cells were first observed within draining lymph nodes, and later in distal iliac and mesenteric lymph nodes and in the spleen. The presence at distal sites was due to migration of locally primed T cells as shown by fingolimod treatment that caused a drastic reduction of proliferated T cells in non-draining lymph nodes and an accumulation of extensively divided T cells within draining lymph nodes. Homing of nasally primed T cells in distal iliac lymph nodes was CD62L-dependent, while entry into mesenteric lymph nodes depended on both CD62L and α4β7, as shown by in vivo antibody-mediated inhibition of T-cell trafficking. These data, elucidating the trafficking of antigen-specific primed T cells to non-draining peripheral and mucosa-associated lymph nodes following nasal immunization, provide relevant insights for the design of vaccination strategies based on mucosal priming.

  2. Original encounter with antigen determines antigen-presenting cell imprinting of the quality of the immune response in mice.

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    Valérie Abadie

    Full Text Available BACKGROUND: Obtaining a certain multi-functionality of cellular immunity for the control of infectious diseases is a burning question in immunology and in vaccine design. Early events, including antigen shuttling to secondary lymphoid organs and recruitment of innate immune cells for adaptive immune response, determine host responsiveness to antigens. However, the sequence of these events and their impact on the quality of the immune response remain to be elucidated. Here, we chose to study Modified Vaccinia virus Ankara (MVA which is now replacing live Smallpox vaccines and is proposed as an attenuated vector for vaccination strategies against infectious diseases. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed in vivo mechanisms triggered following intradermal (i.d. and intramuscular (i.m. Modified Vaccinia virus Ankara (MVA administration. We demonstrated significant differences in the antigen shuttling to lymphoid organs by macrophages (MPhis, myeloid dendritic cells (DCs, and neutrophils (PMNs. MVA i.d. administration resulted in better antigen distribution and more sustained antigen-presenting cells (APCs recruitment into draining lymph nodes than with i.m. administration. These APCs, which comprise both DCs and MPhis, were differentially involved in T cell priming and shaped remarkably the quality of cytokine-producing virus-specific T cells according to the entry route of MVA. CONCLUSIONS/SIGNIFICANCE: This study improves our understanding of the mechanisms of antigen delivery and their consequences on the quality of immune responses and provides new insights for vaccine development.

  3. Circulating human basophils lack the features of professional antigen presenting cells

    OpenAIRE

    Sharma, Meenu; Hegde, Pushpa; Aimanianda, Vishukumar; Beau, Remi; Sénéchal, Helene; Poncet, Pascal; Latgé, Jean-Paul; Kaveri, Srini V; Bayry, Jagadeesh

    2013-01-01

    Recent reports in mice demonstrate that basophils function as antigen presenting cells (APC). They express MHC class II and co-stimulatory molecules CD80 and CD86, capture and present soluble antigens or IgE-antigen complexes and polarize Th2 responses. Therefore, we explored whether human circulating basophils possess the features of professional APC. We found that unlike dendritic cells (DC) and monocytes, steady-state circulating human basophils did not express HLA-DR and co-stimulatory mo...

  4. Viral sequestration of antigen subverts cross presentation to CD8(+ T cells.

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    Eric F Tewalt

    2009-05-01

    Full Text Available Virus-specific CD8(+ T cells (T(CD8+ are initially triggered by peptide-MHC Class I complexes on the surface of professional antigen presenting cells (pAPC. Peptide-MHC complexes are produced by two spatially distinct pathways during virus infection. Endogenous antigens synthesized within virus-infected pAPC are presented via the direct-presentation pathway. Many viruses have developed strategies to subvert direct presentation. When direct presentation is blocked, the cross-presentation pathway, in which antigen is transferred from virus-infected cells to uninfected pAPC, is thought to compensate and allow the generation of effector T(CD8+. Direct presentation of vaccinia virus (VACV antigens driven by late promoters does not occur, as an abortive infection of pAPC prevents production of these late antigens. This lack of direct presentation results in a greatly diminished or ablated T(CD8+ response to late antigens. We demonstrate that late poxvirus antigens do not enter the cross-presentation pathway, even when identical antigens driven by early promoters access this pathway efficiently. The mechanism mediating this novel means of viral modulation of antigen presentation involves the sequestration of late antigens within virus factories. Early antigens and cellular antigens are cross-presented from virus-infected cells, as are late antigens that are targeted to compartments outside of the virus factories. This virus-mediated blockade specifically targets the cross-presentation pathway, since late antigen that is not cross-presented efficiently enters the MHC Class II presentation pathway. These data are the first to describe an evasion mechanism employed by pathogens to prevent entry into the cross-presentation pathway. In the absence of direct presentation, this evasion mechanism leads to a complete ablation of the T(CD8+ response and a potential replicative advantage for the virus. Such mechanisms of viral modulation of antigen presentation

  5. Internalization and presentation of myelin antigens by the brain endothelium guides antigen-specific T cell migration

    Science.gov (United States)

    Lopes Pinheiro, Melissa A; Kamermans, Alwin; Garcia-Vallejo, Juan J; van het Hof, Bert; Wierts, Laura; O'Toole, Tom; Boeve, Daniël; Verstege, Marleen; van der Pol, Susanne MA; van Kooyk, Yvette; de Vries, Helga E; Unger, Wendy WJ

    2016-01-01

    Trafficking of myelin-reactive CD4+ T-cells across the brain endothelium, an essential step in the pathogenesis of multiple sclerosis (MS), is suggested to be an antigen-specific process, yet which cells provide this signal is unknown. Here we provide direct evidence that under inflammatory conditions, brain endothelial cells (BECs) stimulate the migration of myelin-reactive CD4+ T-cells by acting as non-professional antigen presenting cells through the processing and presentation of myelin-derived antigens in MHC-II. Inflamed BECs internalized myelin, which was routed to endo-lysosomal compartment for processing in a time-dependent manner. Moreover, myelin/MHC-II complexes on inflamed BECs stimulated the trans-endothelial migration of myelin-reactive Th1 and Th17 2D2 cells, while control antigen loaded BECs did not stimulate T-cell migration. Furthermore, blocking the interaction between myelin/MHC-II complexes and myelin-reactive T-cells prevented T-cell transmigration. These results demonstrate that endothelial cells derived from the brain are capable of enhancing antigen-specific T cell recruitment. DOI: http://dx.doi.org/10.7554/eLife.13149.001 PMID:27336724

  6. Selective transport of internalized antigens to the cytosol for MHC class I presentation in dendritic cells

    NARCIS (Netherlands)

    Rodriguez, A; Regnault, A; Kleijmeer, M; Ricciardi-Castagnoli, P; Amigorena, S

    1999-01-01

    In order for cytotoxic T cells to initiate immune responses, peptides derived from internalized antigens must be presented to the cytotoxic T cells on major histocompatibility complex (MHC) class I molecules. Here we show that dendritic cells, the only antigen-presenting cells that initiate immune r

  7. Rationally designed inhibitor targeting antigen-trimming aminopeptidases enhances antigen presentation and cytotoxic T-cell responses.

    Science.gov (United States)

    Zervoudi, Efthalia; Saridakis, Emmanuel; Birtley, James R; Seregin, Sergey S; Reeves, Emma; Kokkala, Paraskevi; Aldhamen, Yasser A; Amalfitano, Andrea; Mavridis, Irene M; James, Edward; Georgiadis, Dimitris; Stratikos, Efstratios

    2013-12-01

    Intracellular aminopeptidases endoplasmic reticulum aminopeptidases 1 and 2 (ERAP1 and ERAP2), and as well as insulin-regulated aminopeptidase (IRAP) process antigenic epitope precursors for loading onto MHC class I molecules and regulate the adaptive immune response. Their activity greatly affects the antigenic peptide repertoire presented to cytotoxic T lymphocytes and as a result can regulate cytotoxic cellular responses contributing to autoimmunity or immune evasion by viruses and cancer cells. Therefore, pharmacological regulation of their activity is a promising avenue for modulating the adaptive immune response with possible applications in controlling autoimmunity, in boosting immune responses to pathogens, and in cancer immunotherapy. In this study we exploited recent structural and biochemical analysis of ERAP1 and ERAP2 to design and develop phosphinic pseudopeptide transition state analogs that can inhibit this family of enzymes with nM affinity. X-ray crystallographic analysis of one such inhibitor in complex with ERAP2 validated our design, revealing a canonical mode of binding in the active site of the enzyme, and highlighted the importance of the S2' pocket for achieving inhibitor potency. Antigen processing and presentation assays in HeLa and murine colon carcinoma (CT26) cells showed that these inhibitors induce increased cell-surface antigen presentation of transfected and endogenous antigens and enhance cytotoxic T-cell responses, indicating that these enzymes primarily destroy epitopes in those systems. This class of inhibitors constitutes a promising tool for controlling the cellular adaptive immune response in humans by modulating the antigen processing and presentation pathway. PMID:24248368

  8. Antigen presentation by liposomes bearing class II MHC and membrane IL-1.

    OpenAIRE

    Bakouche, O; LACHMAN, L.B.

    1990-01-01

    Liposomes containing membrane IL-1, Iak, and the antigen conalbumin were evaluated as "synthetic antigen presenting cells." The role of these three molecules in macrophage-T cell interaction was studied by testing their ability to induce the proliferation of a T-cell clone specific to conalbumin (the D10 cell line) or immune spleen cells sensitized three times in vivo with conalbumin. In the latter case, splenic macrophages were eliminated by adherence and a lysomotropic agent. The antigen co...

  9. No Major Role for Insulin-Degrading Enzyme in Antigen Presentation by MHC Molecules

    OpenAIRE

    Culina, Slobodan; Mauvais, François-Xavier; Hsu, Hsiang-Ting; Burgevin, Anne; Guénette, Suzanne; Moser, Anna; van Endert, Peter

    2014-01-01

    Antigen presentation by MHC class I molecules requires degradation of epitope source proteins in the cytosol. Although the preeminent role of the proteasome is clearly established, evidence suggesting a significant role for proteasome-independent generation of class I ligands has been reported repeatedly. However, an enzyme responsible for such a role has not been identified. Recently insulin-degrading enzyme (IDE) was shown to produce an antigenic peptide derived from the tumor antigen MAGE-...

  10. Cross-presentation of cell-associated antigens by MHC class I in dendritic cell subsets

    Directory of Open Access Journals (Sweden)

    Enric eGutiérrez-Martínez

    2015-07-01

    Full Text Available Dendritic cells have the unique ability to pick up dead cells carrying antigens in tissue and migrate to the lymph nodes where they can cross-present cell-associated antigens by MHC class I to CD8+ T cells. There is strong in vivo evidence that the mouse XCR1+ dendritic cells subset acts as a key player in this process. The intracellular processes underlying cross-presentation remain controversial and several pathways have been proposed. Indeed, a wide number of studies have addressed the cellular process of cross-presentation in vitro using a variety of sources of antigen and antigen presenting cells. Here we review the in vivo and in vitro evidence supporting the current mechanistic models and disscuss their physiological relevance to the cross-presentation of cell-associated antigens by dendritic cells subsets

  11. Antigen

    Science.gov (United States)

    An antigen is any substance that causes your immune system to produce antibodies against it. This means your immune ... and is trying to fight it off. An antigen may be a substance from the environment, such ...

  12. Chloroquine inhibits accessory cell presentation of soluble natural and synthetic protein antigens

    DEFF Research Database (Denmark)

    Buus, S; Werdelin, O

    1984-01-01

    We have studied the in vitro effect of the lysosomotrophic agent, chloroquine, on the presentation of soluble protein antigens by guinea pig accessory cells. Chloroquine inhibited the capacity of antigen-pulsed accessory cells to stimulate proliferation in appropriately primed T cells. The effect...

  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. Molecular signals in antigen presentation. II. Activation of cytolytic cells in vitro after ultraviolet radiation or combined gamma and ultraviolet radiation treatment of antigen-presenting cells

    International Nuclear Information System (INIS)

    Murine low-density spleen cells have potent antigen-presenting ability in a hapten-specific cytolytic T lymphocyte (CTL) system using the hapten azobenzenearsonate (ABA). Exposure of these cells to 0.33 KJ/m2 of ultraviolet radiation (UVR) after coupling to hapten results in markedly inhibited antigen-presenting function that can be substantially corrected or bypassed by interleukin 1 (IL 1). These results have been interpreted to reflect an inhibition of Lyt-1+ T cell activation by UVR-treated APC. Treatment of these cells sequentially with 1500 rad of γ-radiation (GR) prior to hapten coupling, followed by 0.33 KJ/m2 of UVR radiation after coupling, results in an antigen-resenting defect only minimally improved by IL 1. However, partially purified interleukin 2 (IL 2) can completely bypass or correct this defect. Thus, combined Cr and UVR induces a different or more profound defect in APC function when compared to UVR alone. However, these cells do provide a signal(s) other than hapten necessary for CTL activation because ABA-coupled high density spleen cells do not activate CTL cells, even with the addition of IL 2. Fluorescence-activated cell sorter analysis demonstrates that exposure of these low density spleen cells to GP or UVR results in decreased I-A antigen expression at 24 hr; exposure to both GR and UVR results in a greater decrease in I-A antigen expression at 24 hr than either alone. The addition of nonhapten-coupled low-density APC partially reconstitutes the ability of combined GR/UVR-treated LD-APC to present antigen, and this effect is enhanced by the administration of exogenous IL 1

  15. Identification of a peptide binding protein that plays a role in antigen presentation

    International Nuclear Information System (INIS)

    The helper T-cell response to globular proteins appears, in general, to require intracellular processing of the antigen, such that a peptide fragment containing the T-cell antigenic determinant is released and transported to and held on the surface of an Ia-expressing, antigen-presenting cell. However, the molecular details underlying these phenomena are largely unknown. The means by which antigenic peptides are anchored on the antigen-presenting cell surface was investigated. A cell surface protein is identified that was isolated by it ability to bind to a 24-amino acid peptide fragment of pigeon cytochrome c, residues 81-104, containing the major antigenic determinant for B10.A mouse T cells. This peptide binding protein, purified from [35S]methionine-labeled cells, appears as two discrete bands of ≅72 and 74 kDa after NaDodSO4/PAGE. The protein can be eluted from the peptide affinity column with equivalent concentrations of either the antigenic pigeon cytochrome c peptide or the corresponding nonantigenic peptide of mouse cytochrome c. However, it does not bind to the native cytochromes c, either of pigeon or mouse, and thus the protein appears to recognize some structure available only in the free peptides. This protein plays a role in antigen presentation. Its expression is not major histocompatibility complex-restricted in that the blocking activity of the antisera can be absorbed on spleen cells from mice of different haplotypes. This peptide binding protein can be isolated from a variety of cell types, including B cells, T cells, and fibroblasts. The anchoring of processed peptides on the cell surface by such a protein may play a role in antigen presentation

  16. Microsomal triglyceride transfer protein lipidation and control of CD1d on antigen-presenting cells

    OpenAIRE

    Dougan, Stephanie K.; Salas, Azucena; Rava, Paul; Agyemang, Amma; Kaser, Arthur; Morrison, Jamin; Khurana, Archana; Kronenberg, Mitchell; Johnson, Caroline; Exley, Mark; Hussain, M. Mahmood; Blumberg, Richard S.

    2005-01-01

    Microsomal triglyceride transfer protein (MTP), an endoplasmic reticulum (ER) chaperone that loads lipids onto apolipoprotein B, also regulates CD1d presentation of glycolipid antigens in the liver and intestine. We show MTP RNA and protein in antigen-presenting cells (APCs) by reverse transcription–polymerase chain reaction and by immunoblotting of mouse liver mononuclear cells and mouse and human B cell lines. Functional MTP, demonstrated by specific triglyceride transfer activity, is prese...

  17. Distinctive localization of antigen-presenting cells in human lymph nodes

    OpenAIRE

    Angel, Catherine E.; Chen, Chun-Jen J.; Horlacher, Oliver C.; Winkler, Sintia; John, Thomas; Browning, Judy; MacGregor, Duncan; Cebon, Jonathan; Dunbar, P. Rod

    2009-01-01

    Professional antigen-presenting cells (APCs) are sentinel cells of the immune system that present antigen to T lymphocytes and mediate an appropriate immune response. It is therefore surprising that knowledge of the professional APCs in human lymph nodes is limited. Using 3-color immunohistochemistry, we have identified APCs in human lymph nodes, excluding plasmacytoid APCs, that fall into 2 nonoverlapping classes: (1) CD209+ APCs, coexpressing combinations of CD206, CD14, and CD68, that occu...

  18. Autoinflammation and HLA-B27: Beyond Antigen Presentation.

    Science.gov (United States)

    Sibley, Cailin H

    2016-08-01

    HLA-B27 associated disorders comprise a group of inflammatory conditions which have in common an association with the HLA class I molecule, HLA-B27. Given this association, these diseases are classically considered disorders of adaptive immunity. However, mounting data are challenging this assumption and confirming that innate immunity plays a more prominent role in pathogenesis than previously suspected. In this review, the concept of autoinflammation is discussed and evidence is presented from human and animal models to support a key role for innate immunity in HLA-B27 associated disorders. PMID:27229619

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Human parvovirus B19 induced apoptotic bodies contain altered self-antigens that are phagocytosed by antigen presenting cells.

    Directory of Open Access Journals (Sweden)

    Kanoktip Thammasri

    Full Text Available Human parvovirus B19 (B19V from the erythrovirus genus is known to be a pathogenic virus in humans. Prevalence of B19V infection has been reported worldwide in all seasons, with a high incidence in the spring. B19V is responsible for erythema infectiosum (fifth disease commonly seen in children. Its other clinical presentations include arthralgia, arthritis, transient aplastic crisis, chronic anemia, congenital anemia, and hydrops fetalis. In addition, B19V infection has been reported to trigger autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. However, the mechanisms of B19V participation in autoimmunity are not fully understood. B19V induced chronic disease and persistent infection suggests B19V can serve as a model for viral host interactions and the role of viruses in the pathogenesis of autoimmune diseases. Here we investigate the involvement of B19V in the breakdown of immune tolerance. Previously, we demonstrated that the non-structural protein 1 (NS 1 of B19V induces apoptosis in non-permissive cells lines and that this protein can cleave host DNA as well as form NS1-DNA adducts. Here we provide evidence that through programmed cell death, apoptotic bodies (ApoBods are generated by B19V NS1 expression in a non-permissive cell line. Characterization of purified ApoBods identified potential self-antigens within them. In particular, signature self-antigens such as Smith, ApoH, DNA, histone H4 and phosphatidylserine associated with autoimmunity were present in these ApoBods. In addition, when purified ApoBods were introduced to differentiated macrophages, recognition, engulfment and uptake occurred. This suggests that B19V can produce a source of self-antigens for immune cell processing. The results support our hypothesis that B19V NS1-DNA adducts, and nucleosomal and lysosomal antigens present in ApoBods created in non-permissive cell lines, are a source of self-antigens.

  1. 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.

  2. A Population Dynamics Analysis of the Interaction between Adaptive Regulatory T Cells and Antigen Presenting Cells

    OpenAIRE

    Fouchet, David; Regoes, Roland

    2008-01-01

    Background Regulatory T cells are central actors in the maintenance of tolerance of self-antigens or allergens and in the regulation of the intensity of the immune response during infections by pathogens. An understanding of the network of the interaction between regulatory T cells, antigen presenting cells and effector T cells is starting to emerge. Dynamical systems analysis can help to understand the dynamical properties of an interaction network and can shed light on the different tasks t...

  3. Evasion of peptide, but not lipid antigen presentation, through pathogen-induced dendritic cell maturation

    OpenAIRE

    Hava, David L.; van der Wel, Nicole ,; Cohen, Nadia; Dascher, Christopher C.; Houben, Diane; León, Luis; Agarwal, Sandeep; Sugita, Masahiko; van Zon, Maaike; Kent, Sally C.; Shams, Homayoun; Peters, Peter J.; Brenner, Michael B.

    2008-01-01

    Dendritic cells (DC) present lipid and peptide antigens to T cells on CD1 and MHC Class II (MHCII), respectively. The relative contribution of these systems during the initiation of adaptive immunity after microbial infection is not characterized. MHCII molecules normally acquire antigen and rapidly traffic from phagolysosomes to the plasma membrane as part of DC maturation, whereas CD1 molecules instead continually recycle between these sites before, during, and after DC maturation. We find ...

  4. Hepatitis C virus and ethanol alter antigen presentation in liver cells

    Institute of Scientific and Technical Information of China (English)

    Natalia A Osna

    2009-01-01

    Alcoholic patients have a high incidence of hepatitis Cvirus (HCV) infection. Alcohol consumption enhances the severity of the HCV disease course and worsens the outcome of chronic hepatitis C. The accumulation of virally infected cells in the liver is related to the HCVinduced inability of the immune system to recognizeinfected cells and to develop the immune responses. This review covers the effects of HCV proteins and ethanol on major histocompatibility complex (MHC) classⅠ- and class Ⅱ-restricted antigen presentation. Here, we discuss the liver which functions as an immune privilege organ; factors, which affect cleavage and loading of antigenic peptides onto MHC classⅠand class Ⅱ in hepatocytes and dendritic cells, and the modulating effects of ethanol and HCV on antigen presentation by liver cells. Altered antigen presentation in the liver limits the ability of the immune system to clear HCV and infected cells and contributes to disease progression. HCV by itself affects dendritic cell function, switching their cytokine profile to the suppressive phenotype of interleukin-10 (IL-10) and transforming growth factor beta (TGFβ) predominance,preventing cell maturation and allostimulation capacity.The synergistic action of ethanol with HCV results in the suppression of MHC class Ⅱ-restricted antigen presentation. In addition, ethanol metabolism and HCV proteins reduce proteasome function and interferon signaling, thereby suppressing the generation of peptides for MHC classⅠ-restricted antigen presentation.Collectively, ethanol exposure further impairs antigen presentation in HCV-infected liver cells, which may provide a partial explanation for exacerbations and the poor outcome of HCV infection in alcoholics.

  5. Facts on the fragmentation of antigens in presenting cells, on the association of antigen fragments with MHC molecules in cell-free systems, and speculation on the cell biology of antigen processing

    DEFF Research Database (Denmark)

    Werdelin, O; Mouritsen, S; Petersen, B L;

    1988-01-01

    The processing of a protein antigen is a multi-step event taking place in antigen-presenting cells. Processing is a prerequisite for the recognition of most antigens by T lymphocytes. The antigen is ingested by endocytosis, transported to an acid cellular compartment and subjected to proteolytic...... fragmentation. Some of the antigen fragments bind to MHC class II molecules and are transported to the surface of the antigen-presenting cell where the actual presentation to T lymphocytes occurs. The nature of the processed antigen, how and where it is derived and subsequently becomes associated with MHC...... molecules are the questions discussed in this review. To us, the entire concept of processing has appeal not only because it explains some hitherto well-established, but poorly understood, phenomena such as the fact that T lymphocytes focus their attention entirely upon antigens on other cells. It has...

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Antigen presentation by non-immune B-cell hybridoma clones: presentation of synthetic antigenic sites reveals clones that exhibit no specificity and clones that present only one epitope

    Science.gov (United States)

    Cohly, H. H.; Morrison, D. R.; Atassi, M. Z.

    1989-01-01

    Recently, we reported the preparation and antigen-presenting properties of hybridoma B-cell clones obtained after fusing non-secreting, non-antigen presenting Balb/c 653-myeloma cells with non-immune SJL spleen cells. It was found that antigen presentation at the clonal level can be specific or non-specific, depending on the particular B-cell clone. In the present work, one specific and one general presenter B-cell clones were tested for their epitope presentation ability to SJL T-cells that were specific to lysozyme or myoglobin. B-cell clone A1G12, a general presenter which presented both lysozyme and myoglobin to their respective T-cell lines, was found to present all five myoglobin epitopes while clone A1L16, a lysozyme specific presenter presented only one of the three epitopes of lysozyme. The latter reveals a hitherto unknown submolecular specificity (to a given epitope within a protein) for antigen presenting cells at the clonal level. Therefore, the specificity of T-cell recognition does not only derive from the T-cell but may also be dependent on the epitope specificity of the antigen-presenting B-cell.

  8. 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.

  9. Synthetic pathogens for integrated biophysical and genetic dissection of antigen cross-presentation

    OpenAIRE

    Freitas, Rui Pedro da Silva Albuquerque e, 1980-

    2010-01-01

    Tese de doutoramento, Ciências Biomédicas (Ciências Morfológicas), Universidade de Lisboa, Faculdade de Medicina, 2010 The study of host-pathogen interactions is crucial to unveil the diversity of the immune response outcome. Dendritic Cells (DCs) play a central role in the initiation and regulation of T-Cell immunity, functioning as master switches that control whether the outcome of antigen presentation results in tolerance, or immunity. Antigen cross-presentation is a necessary mechanis...

  10. No major role for insulin-degrading enzyme in antigen presentation by MHC molecules.

    Directory of Open Access Journals (Sweden)

    Slobodan Culina

    Full Text Available Antigen presentation by MHC class I molecules requires degradation of epitope source proteins in the cytosol. Although the preeminent role of the proteasome is clearly established, evidence suggesting a significant role for proteasome-independent generation of class I ligands has been reported repeatedly. However, an enzyme responsible for such a role has not been identified. Recently insulin-degrading enzyme (IDE was shown to produce an antigenic peptide derived from the tumor antigen MAGE-A3 in an entirely proteasome-independent manner, raising the question of the global impact of IDE in MHC class I antigen processing. Here we report that IDE knockdown in human cell lines, or knockout in two different mouse strains, has no effect on cell surface expression of various MHC class I molecules, including allomorphs such as HLA-A3 and HLA-B27 suggested to be loaded in an at least a partly proteasome-independent manner. Moreover, reduced or absent IDE expression does not affect presentation of five epitopes including epitopes derived from beta amyloid and proinsulin, two preferred IDE substrates. Thus, IDE does not play a major role in MHC class I antigen processing, confirming the dominant and almost exclusive role of the proteasome in cytosolic production of MHC class I ligands.

  11. No major role for insulin-degrading enzyme in antigen presentation by MHC molecules.

    Science.gov (United States)

    Culina, Slobodan; Mauvais, François-Xavier; Hsu, Hsiang-Ting; Burgevin, Anne; Guénette, Suzanne; Moser, Anna; van Endert, Peter

    2014-01-01

    Antigen presentation by MHC class I molecules requires degradation of epitope source proteins in the cytosol. Although the preeminent role of the proteasome is clearly established, evidence suggesting a significant role for proteasome-independent generation of class I ligands has been reported repeatedly. However, an enzyme responsible for such a role has not been identified. Recently insulin-degrading enzyme (IDE) was shown to produce an antigenic peptide derived from the tumor antigen MAGE-A3 in an entirely proteasome-independent manner, raising the question of the global impact of IDE in MHC class I antigen processing. Here we report that IDE knockdown in human cell lines, or knockout in two different mouse strains, has no effect on cell surface expression of various MHC class I molecules, including allomorphs such as HLA-A3 and HLA-B27 suggested to be loaded in an at least a partly proteasome-independent manner. Moreover, reduced or absent IDE expression does not affect presentation of five epitopes including epitopes derived from beta amyloid and proinsulin, two preferred IDE substrates. Thus, IDE does not play a major role in MHC class I antigen processing, confirming the dominant and almost exclusive role of the proteasome in cytosolic production of MHC class I ligands. PMID:24516642

  12. Equine infectious anemia virus-infected dendritic cells retain antigen presentation capability

    International Nuclear Information System (INIS)

    To determine if equine monocyte-derived dendritic cells (DC) were susceptible to equine infectious anemia virus (EIAV) infection, ex vivo-generated DC were infected with virus in vitro. EIAV antigen was detected by immunofluorescence 3 days post-infection with maximum antigen being detected on day 4, whereas there was no antigen detected in DC incubated with the same amount of heat-inactivated EIAV. No cytolytic activity was observed after EIAVWSU5 infection of DC. These monocyte-derived DC were more effective than macrophages and B cells in stimulating allogenic T lymphocytes. Both infected macrophages and DC stimulated similar levels of memory CTL responses in mixtures of CD8+ and CD4+ cells as detected with 51Cr-release assays indicating that EIAV infection of DC did not alter antigen presentation. However, EIAV-infected DC were more effective than infected macrophages when used to stimulate memory CTL in isolated CD8+ cells. The maintenance of antigen processing and presenting function by EIAV-infected DC in vitro suggests that this function is maintained during in vivo infection

  13. The T-cell anergy induced by Leishmania amazonensis antigens is related with defective antigen presentation and apoptosis

    Directory of Open Access Journals (Sweden)

    Roberta O. Pinheiro

    2004-09-01

    Full Text Available Leishmania amazonensis is the main agent of diffuse cutaneous leishmaniasis, a disease associated with anergic immune responses. In this study we show that the crude antigen of Leishmania amazonensis (LaAg but not L. braziliensis promastigotes (LbAg contains substances that suppress mitogenic and spontaneous proliferative responses of T cells. The suppressive substances in LaAg are thermoresistant (100ºC/1h and partially dependent on protease activity. T cell anergy was not due to a decreased production of growth factors as it was not reverted by addition of exogenous IL-2, IL-4, IFN-gamma or IL-12. LaAg did not inhibit anti-CD3-induced T cell activation, suggesting that anergy was due to a defect in antigen presentation. It was also not due to cell necrosis, but was accompanied by expressive DNA fragmentation in lymph node cells, indicative of apoptosis. Although pre-incubation of macrophages with LaAg prevented their capacity to present antigens, this effect was not due to apoptosis of the former. These results suggest that the T cell anergy found in diffuse leishmaniasis may be the result of parasite antigen-driven apoptosis of those cells following defective antigen presentation.A Leishmania amazonensis é o principal agente etiológico da leishmaniose cutânea difusa, uma doença associada a respostas imunes anérgicas. Neste estudo nós mostramos que o extrato bruto de promastigotas de Leishmania amazonensis (LaAg, mas não de L. braziliensis (LbAg, contém substâncias que suprimem respostas proliferativas, espontâneas e mitogênicas, de células T. As substâncias supressoras no LaAg são termo-resistentes (100°C/1h e parcialmente dependentes da atividade de proteases. A anergia de células T não foi devida à diminuição na produção de fatores de crescimento, uma vez que não foi revertida pela adição de: IL-2, IL-4, IFN-gama ou IL-12. O LaAg não inibiu a ativação de células T induzida por anti-CD3, sugerindo que a anergia

  14. ImmunoChip Study Implicates Antigen Presentation to T Cells in Narcolepsy

    DEFF Research Database (Denmark)

    Faraco, Juliette; Lin, Ling; Kornum, Birgitte Rahbek;

    2013-01-01

    with hypocretin-deficient narcolepsy and 10,421 controls, all of European ancestry, using a custom genotyping array (ImmunoChip). Three loci located outside the Human Leukocyte Antigen (HLA) region on chromosome 6 were significantly associated with disease risk. In addition to a strong signal in the T...... cell receptor alpha (TRA@), variants in two additional narcolepsy loci, Cathepsin H (CTSH) and Tumor necrosis factor (ligand) superfamily member 4 (TNFSF4, also called OX40L), attained genome-wide significance. These findings underline the importance of antigen presentation by HLA Class II to T cells...

  15. Antigen-presenting cells in human cutaneous leishmaniasis due to Leishmania major

    DEFF Research Database (Denmark)

    ElHassan, A M; Gaafar, A; Theander, T G

    1995-01-01

    In this study biopsies from skin lesions and draining lymph nodes of patients suffering from cutaneous leishmaniasis caused by Leishmania major were examined by immunohistochemistry, and by light and electron microscopy to identify the types of antigen-presenting cells (APC) and their location. APC......, identified morphologically and by their expression of specific cell markers, included Langerhans cells, macrophages, follicular dendritic cells, and interdigitating reticulum cells of the paracortex of lymph nodes. These cells expressed MHC class II antigens and contained Leishmania antigen. Since some...... keratinocytes and endothelial cells also showed these characteristics, they may also act as APC. By examining tissue samples from skin lesions and draining lymph nodes it was possible to follow the probable route of trafficking of various inflammatory cells between the skin lesion and lymph nodes. Leishmania...

  16. A population dynamics analysis of the interaction between adaptive regulatory T cells and antigen presenting cells.

    Directory of Open Access Journals (Sweden)

    David Fouchet

    Full Text Available BACKGROUND: Regulatory T cells are central actors in the maintenance of tolerance of self-antigens or allergens and in the regulation of the intensity of the immune response during infections by pathogens. An understanding of the network of the interaction between regulatory T cells, antigen presenting cells and effector T cells is starting to emerge. Dynamical systems analysis can help to understand the dynamical properties of an interaction network and can shed light on the different tasks that can be accomplished by a network. METHODOLOGY AND PRINCIPAL FINDINGS: We used a mathematical model to describe a interaction network of adaptive regulatory T cells, in which mature precursor T cells may differentiate into either adaptive regulatory T cells or effector T cells, depending on the activation state of the cell by which the antigen was presented. Using an equilibrium analysis of the mathematical model we show that, for some parameters, the network has two stable equilibrium states: one in which effector T cells are strongly regulated by regulatory T cells and another in which effector T cells are not regulated because the regulatory T cell population is vanishingly small. We then simulate different types of perturbations, such as the introduction of an antigen into a virgin system, and look at the state into which the system falls. We find that whether or not the interaction network switches from the regulated (tolerant state to the unregulated state depends on the strength of the antigenic stimulus and the state from which the network has been perturbed. CONCLUSION/SIGNIFICANCE: Our findings suggest that the interaction network studied in this paper plays an essential part in generating and maintaining tolerance against allergens and self-antigens.

  17. CLIC1 regulates dendritic cell antigen processing and presentation by modulating phagosome acidification and proteolysis

    Science.gov (United States)

    Salao, Kanin; Jiang, Lele; Li, Hui; Tsai, Vicky W.-W.; Husaini, Yasmin; Curmi, Paul M. G.; Brown, Louise J.; Brown, David A.

    2016-01-01

    ABSTRACT Intracellular chloride channel protein 1 (CLIC1) participates in inflammatory processes by regulating macrophage phagosomal functions such as pH and proteolysis. Here, we sought to determine if CLIC1 can regulate adaptive immunity by actions on dendritic cells (DCs), the key professional antigen presenting cells. To do this, we first generated bone marrow-derived DCs (BMDCs) from germline CLIC1 gene-deleted (CLIC1−/−) and wild-type (CLIC1+/+) mice, then studied them in vitro and in vivo. We found phagocytosis triggered cytoplasmic CLIC1 translocation to the phagosomal membrane where it regulated phagosomal pH and proteolysis. Phagosomes from CLIC1−/− BMDCs displayed impaired acidification and proteolysis, which could be reproduced if CLIC1+/+, but not CLIC1−/− cells, were treated with IAA94, a CLIC family ion channel blocker. CLIC1−/− BMDC displayed reduced in vitro antigen processing and presentation of full-length myelin oligodendrocyte glycoprotein (MOG) and reduced MOG-induced experimental autoimmune encephalomyelitis. These data suggest that CLIC1 regulates DC phagosomal pH to ensure optimal processing of antigen for presentation to antigen-specific T-cells. Further, they indicate that CLIC1 is a novel therapeutic target to help reduce the adaptive immune response in autoimmune diseases. PMID:27113959

  18. Adjuvant effects of liposomes containing lipid A: enhancement of liposomal antigen presentation and recruitment of macrophages.

    OpenAIRE

    Verma, J N; Rao, M.; Amselem, S; Krzych, U; Alving, C R; Green, S J; Wassef, N M

    1992-01-01

    Liposomes containing lipid A induced potent humoral immune responses in mice against an encapsulated malaria antigen (R32NS1) containing NANP epitopes. The immune response was not enhanced by lipid A alone or by empty liposomes containing lipid A. Experiments to investigate the adjuvant mechanisms of liposomes and lipid A revealed that liposome-encapsulated R32NS1 was actively presented by bone marrow-derived macrophages to NANP-specific cloned T cells. The degree of presentation was related ...

  19. Antigen presentation by murine epidermal langerhans cells and its alteration by ultraviolet B light

    International Nuclear Information System (INIS)

    Mice that are chronically exposed in vivo to ultraviolet B light (UV-B) display altered immunologic reactivity to various antigenic stimuli. A possible mode of UV-B action is that it exerts adverse effects on antigen-presenting cell function. Because the epidermis is the only tissue that is naturally subject to UV exposure we investigated if murine epidermal cells (EC) could perform an antigen presentation function and, if so, could this function be altered by UV-B irradiation. For this purpose, T cells immune to purified protein derivative of tuberculin (PPD) and dinitrophenylated ovalbumin (DNP6-OVA) from either BALB/c or C3H/He mice were incubated with syngeneic, semisyngeneic, or allogeneic EC or, for control purposes, with peritoneal exudate cells (PEC) that had been pulse-exposed to either the immunizing antigens or, as controls, left unpulsed, or pulsed to human serum albumin (HSA). After 4 days of culture, T cell proliferation was assessed by 3H-thymidine incorporation. PPD- and DNP/6-OVA pulsed, but not HSA-pulsed EC and PEC, induced vigorous proliferation of syngeneic and semisyngeneic, but not allogeneic, immune T cells. Pretreatment of stimulator cells with specific anti-Ia serum and complement virtually abolished this response, which indicated that among EC, Ia-bearing Langerhans cells are the critical stimulators. Exposure of EC either before or after pulsing to UV-B resulted in a dose-dependent impairment of antigen-specific T cell proliferation; the T proliferative response was abolished after administration of 20 mJ/cm2 UV-B. UV-B in the dose range employed did not produce immediate lethal cell damage, premature death of cultured EC, or toxic factors inhibitory for T cell proliferation

  20. Salt bridge residues between I-Ak dimer of dimers alpha-chains modulate antigen presentation.

    Science.gov (United States)

    Yadati, S; Nydam, T; Demian, D; Wade, T K; Gabriel, J L; Barisas, B G; Wade, W F

    1999-03-15

    Class II dimers of dimers are predicted to have functional significance in antigen presentation. The putative contact amino acids of the I-Ak class II dimer of dimers have been identified by molecular modeling based on the DR1 crystal structure (Nydam et al., Int. Immunol. 10, 1237,1998). We have previously reported the role in antigen presentation of dimer of dimers contact amino acids located in the C-terminal domains of the alpha- and beta-chains of class II. Our calculations show that residues Ealpha89 and Ralpha145 in the alpha2-domain form an inter alpha-chain salt bridge between pairs of alphabeta-heterodimers. Other residues, Qalpha92 and Nalpha115, may be involved in close association in that part of the alpha-chain. We investigated the role of these amino acids on class II expression and antigen presentation. Class II composed of an Ealpha89K substituted alpha-chain paired with a wt beta-chain exhibited inhibited antigen presentation and expression of alpha-chain serologic epitopes. In contrast, mutation of Ralpha145E had less affect on antigen presentation and did not affect I-Ak serologic epitopes. Interchanging charges of the salt bridge residues by expressing both Ralpha145E and Ealpha89K on the same chain obviated the large negative effect of the Ealpha89K mutation on antigen presentation but not on the serologic epitopes. Our results are similar for those reported for mutation of DR3's inter-chain salt bridge with the exception that double mutants did not moderate the DR3 defect. Interestingly, the amino acids differences between I-A and DR change the location of the inter-chain salt bridges. In DR1 these residues are located at positions Ealpha88 and Kalpha111; in I-Ak these residues are located at position Ealpha89 and Ralpha145. Inter alpha-chain salt bridges are thus maintained in various class II molecules by amino acids located in different parts of the alpha2-domain. This conservation of structure suggests that considerable functional

  1. 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.

  2. Antigen presenting cells in the skin of a patient with hair loss and systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2009-09-01

    Full Text Available Context: Hair loss is one of the most striking clinical features of active systemic lupus erythematosus (SLE, however, very few studies have investigated the immunological features of this process. Case report: We describe a 33 years old female who presented with scalp hair loss and arthralgias. Physical examination revealed erythematous plaques on the nose and scalp, with bitemporal hair loss. Scalp biopsies revealed epidermal hyperkeratosis, with a mild interface infiltrate of lymphocytes and histiocytes and a superficial and deep, perivascular and periadnexal infiltrate of mostly CD4 positive cells. Antibodies to HAM 56, CD68, CD1a, S-100, mast cell tryptase and c-kit/CD117 were strongly positive around the hair follicles, and in the adjacent sebaceous glands. Conclusion: We present the first report showing a significant presence of several antigen presenting cells around the hair follicular units in a patient with alopecia in active SLE. Today, antigen presenting cells and dendritic cells (DC are modeled as the master regulators of human immunity. One aspect that has become clearly appreciated is the great diversity of DC subtypes, each with considerable functional differences. Thus, we suggest that APC and DCs are equipped with Pattern Recognition Receptors (PRRs to some hair follicular unit antigens; that these innate sensors recognize conserved molecular patterns on self- tissue, and play a significant role in the pathophysiology of alopecia in SLE patients.

  3. Antigen presenting cells in the skin of a patient with hair loss and systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2009-01-01

    Full Text Available Context: Hair loss is one of the most striking clinical features of active systemic lupus erythematosus (SLE, however, very few studies have investigated the immunological features of this process. Case report: We describe a 33 years old female who presented with scalp hair loss and arthralgias. Physical examination revealed erythematous plaques on the nose and scalp, with bitemporal hair loss. Scalp biopsies revealed epidermal hyperkeratosis, with a mild interface infiltrate of lymphocytes and histiocytes and a superficial and deep, perivascular and periadnexal infiltrate of mostly CD4 positive cells. Antibodies to HAM 56, CD68, CD1a, S-100, mast cell tryptase and c-kit/CD117 were strongly positive around the hair follicles, and in the adjacent sebaceous glands. Conclusion : We present the first report showing a significant presence of several antigen presenting cells around the hair follicular units in a patient with alopecia in active SLE. Today, antigen presenting cells and dendritic cells (DC are modeled as the master regulators of human immunity. One aspect that has become clearly appreciated is the great diversity of DC subtypes, each with considerable functional differences. Thus, we suggest that APC and DCs are equipped with Pattern Recognition Receptors (PRRs to some hair follicular unit antigens; that these innate sensors recognize conserved molecular patterns on self- tissue, and play a significant role in the pathophysiology of alopecia in SLE patients

  4. CD13 Regulates Dendritic Cell Cross-presentation and T Cell Responses by Inhibiting Receptor-Mediated Antigen Uptake

    OpenAIRE

    Ghosh, Mallika; McAuliffe, Beata; Subramani, Jaganathan; Basu, Sreyashi; Shapiro, Linda H.

    2012-01-01

    Dendritic cell (DC) antigen cross-presentation is generally associated with immune responses to tumors and viral antigens and enhancing this process is a focus of tumor vaccine design. In this study, we found that the myeloid cell surface peptidase CD13 is highly and specifically expressed on the subset of DCs responsible for cross-presentation, the CD8+ murine splenic DCs. In vivo studies indicated that lack of CD13 significantly enhanced T cell responses to soluble OVA antigen, although dev...

  5. The perivascular phagocyte of the mouse pineal gland: An antigen-presenting cell

    DEFF Research Database (Denmark)

    Møller, Morten; Rath, Martin F; Klein, David C

    2006-01-01

    The perivascular space of the rat pineal gland is known to contain phagocytic cells that are immunoreactive for leukocyte antigens, and thus they appear to belong to the macrophage/microglial cell line. These cells also contain MHC class II proteins. We investigated this cell type in the pineal...... gland of mice. Actively phagocytosing cells with a prominent lysosomal system were found in the pericapillary spaces of the mouse pineal gland following intravenous injection of horseradish peroxidase. The cells also exhibited strong acid phosphatase activity. Perivascular cells were immunopositive for...... MHC class II protein and for CD68, a marker of monocytes/phagocytes. This study verifies that perivascular phagocytes with antigen-presenting properties are present in the mouse pineal gland....

  6. Antigen-presenting cells transfected with Hsp65 messenger RNA fail to treat experimental tuberculosis

    International Nuclear Information System (INIS)

    In the last several years, the use of dendritic cells has been studied as a therapeutic strategy against tumors. Dendritic cells can be pulsed with peptides or full-length protein, or they can be transfected with DNA or RNA. However, comparative studies suggest that transfecting dendritic cells with messenger RNA (mRNA) is superior to other antigen-loading techniques in generating immunocompetent dendritic cells. In the present study, we evaluated a new therapeutic strategy to fight tuberculosis using dendritic cells and macrophages transfected with Hsp65 mRNA. First, we demonstrated that antigen-presenting cells transfected with Hsp65 mRNA exhibit a higher level of expression of co-stimulatory molecules, suggesting that Hsp65 mRNA has immunostimulatory properties. We also demonstrated that spleen cells obtained from animals immunized with mock and Hsp65 mRNA-transfected dendritic cells were able to generate a mixed Th1/Th2 response with production not only of IFN-γ but also of IL-5 and IL-10. In contrast, cells recovered from mice immunized with Hsp65 mRNA-transfected macrophages were able to produce only IL-5. When mice were infected with Mycobacterium tuberculosis and treated with antigen-presenting cells transfected with Hsp65 mRNA (therapeutic immunization), we did not detect any decrease in the lung bacterial load or any preservation of the lung parenchyma, indicating the inability of transfected cells to confer curative effects against tuberculosis. In spite of the lack of therapeutic efficacy, this study reports for the first time the use of antigen-presenting cells transfected with mRNA in experimental tuberculosis

  7. Antigen Presentation and T-Cell Activation Are Critical for RBP4-Induced Insulin Resistance.

    Science.gov (United States)

    Moraes-Vieira, Pedro M; Castoldi, Angela; Aryal, Pratik; Wellenstein, Kerry; Peroni, Odile D; Kahn, Barbara B

    2016-05-01

    Adipose tissue (AT) inflammation contributes to impaired insulin action, which is a major cause of type 2 diabetes. RBP4 is an adipocyte- and liver-derived protein with an important role in insulin resistance, metabolic syndrome, and AT inflammation. RBP4 elevation causes AT inflammation by activating innate immunity, which elicits an adaptive immune response. RBP4-overexpressing mice (RBP4-Ox) are insulin resistant and glucose intolerant and have increased AT macrophages and T-helper 1 cells. We show that high-fat diet-fed RBP4(-/-) mice have reduced AT inflammation and improved insulin sensitivity versus wild type. We also elucidate the mechanism for RBP4-induced macrophage antigen presentation and subsequent T-cell activation. In RBP4-Ox, AT macrophages display enhanced c-Jun N-terminal kinase, extracellular signal-related kinase, and p38 phosphorylation. Inhibition of these pathways and of NF-κB reduces activation of macrophages and CD4 T cells. MyD88 is an adaptor protein involved in proinflammatory signaling. In macrophages from MyD88(-/-) mice, RBP4 fails to stimulate secretion of tumor necrosis factor, IL-12, and IL-6 and CD4 T-cell activation. In vivo blockade of antigen presentation by treating RBP4-Ox mice with CTLA4-Ig, which blocks costimulation of T cells, is sufficient to reduce AT inflammation and improve insulin resistance. Thus, MyD88 and downstream mitogen-activated protein kinase and NF-κB pathways are necessary for RBP4-induced macrophage antigen presentation and subsequent T-cell activation. Also, blocking antigen presentation with CTLA4-Ig improves RBP4-induced insulin resistance and macrophage-induced T-cell activation. PMID:26936962

  8. Self-antigen presentation by dendritic cells and lymphoid stroma and its implications for autoimmunity

    OpenAIRE

    Lukacs-Kornek, Veronika; Turley, Shannon J.

    2010-01-01

    The induction and maintenance of T cell tolerance is essential to prevent autoimmunity. A combination of central and peripheral mechanisms acts to control autoreactive T cells. In secondary lymphoid organs, dendritic cells (DCs) presenting self-antigen were thought to play a major role in the induction of peripheral T cell tolerance. Multiple recent studies have demonstrated that DCs are not absolutely essential to induce and maintain tolerance. Furthermore, it has also been recently shown th...

  9. Antigen-presenting cells transfected with Hsp65 messenger RNA fail to treat experimental tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, C.D.; Trombone, A.P.F.; Lorenzi, J.C.C.; Almeida, L.P.; Gembre, A.F.; Padilha, E. [Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Ramos, S.G. [Departamento de Patologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Silva, C.L.; Coelho-Castelo, A.A.M. [Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2012-09-21

    In the last several years, the use of dendritic cells has been studied as a therapeutic strategy against tumors. Dendritic cells can be pulsed with peptides or full-length protein, or they can be transfected with DNA or RNA. However, comparative studies suggest that transfecting dendritic cells with messenger RNA (mRNA) is superior to other antigen-loading techniques in generating immunocompetent dendritic cells. In the present study, we evaluated a new therapeutic strategy to fight tuberculosis using dendritic cells and macrophages transfected with Hsp65 mRNA. First, we demonstrated that antigen-presenting cells transfected with Hsp65 mRNA exhibit a higher level of expression of co-stimulatory molecules, suggesting that Hsp65 mRNA has immunostimulatory properties. We also demonstrated that spleen cells obtained from animals immunized with mock and Hsp65 mRNA-transfected dendritic cells were able to generate a mixed Th1/Th2 response with production not only of IFN-γ but also of IL-5 and IL-10. In contrast, cells recovered from mice immunized with Hsp65 mRNA-transfected macrophages were able to produce only IL-5. When mice were infected with Mycobacterium tuberculosis and treated with antigen-presenting cells transfected with Hsp65 mRNA (therapeutic immunization), we did not detect any decrease in the lung bacterial load or any preservation of the lung parenchyma, indicating the inability of transfected cells to confer curative effects against tuberculosis. In spite of the lack of therapeutic efficacy, this study reports for the first time the use of antigen-presenting cells transfected with mRNA in experimental tuberculosis.

  10. Exposure to ozone enhances antigen-presenting activity concentration dependently in rats

    International Nuclear Information System (INIS)

    The effect of ozone (O3) on the symptoms of allergic asthma and the mechanisms underlying have not yet been fully elucidated. Antigen presentation is one of the factors contributing to the allergic reaction. Therefore, we investigated the effects of repeated exposure to O3 on antigen-presenting (AP) activity, on the expression of cell-surface molecules associated with antigen presentation (Ia, B7.1, B7.2 and CD11b/c) in bronchoalveolar lavage cells (BAL cells), and on allergic asthma-like symptoms. Rats were exposed to 0.3, 0.56, 1 ppm O3 or filtered air for a 3-day period every 2 weeks, this was replicated three times. AP activity was assessed by measuring antigen-specific T-cell proliferation; and the expression of cell-surface molecules, by flow cytometry. Rats were also made to inhale aerosolized 1% ovalbumin (OVA) or saline for 10 min post-exposure to O3, and allergic asthma-like symptoms were measured by determining the increase in enhanced pause (Penh), which correlates well with lung resistance. O3 increased both AP activity and expression of Ia and costimulatory molecules in BAL cells concentration dependently. It also increased lung resistance, and the increase in lung resistance after O3 exposure was significantly higher in the OVA-inhaled group than in the saline-inhaled group. The present results show that O3 increased AP activity concentration dependently and suggest that O3 might aggravate allergy symptoms by enhancing AP activity

  11. A Novel Laser Vaccine Adjuvant Increases the Motility of Antigen Presenting Cells

    OpenAIRE

    Farinelli, Bill; Doukas, Apostolos; Gelfand, Jeffrey Alan; Anderson, Richard Rox; Mei X. Wu; Chen, Xinyuan; Kim, Pilhan; Yun, Seok-Hyun

    2010-01-01

    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...

  12. Anticancer chemotherapy-induced intratumoral recruitment and differentiation of antigen-presenting cells.

    Science.gov (United States)

    Ma, Yuting; Adjemian, Sandy; Mattarollo, Stephen R; Yamazaki, Takahiro; Aymeric, Laetitia; Yang, Heng; Portela Catani, João Paulo; Hannani, Dalil; Duret, Helene; Steegh, Kim; Martins, Isabelle; Schlemmer, Frederic; Michaud, Mickaël; Kepp, Oliver; Sukkurwala, Abdul Qader; Menger, Laurie; Vacchelli, Erika; Droin, Nathalie; Galluzzi, Lorenzo; Krzysiek, Roman; Gordon, Siamon; Taylor, Philip R; Van Endert, Peter; Solary, Eric; Smyth, Mark J; Zitvogel, Laurence; Kroemer, Guido

    2013-04-18

    The therapeutic efficacy of anthracyclines relies on antitumor immune responses elicited by dying cancer cells. How chemotherapy-induced cell death leads to efficient antigen presentation to T cells, however, remains a conundrum. We found that intratumoral CD11c(+)CD11b(+)Ly6C(hi) cells, which displayed some characteristics of inflammatory dendritic cells and included granulomonocytic precursors, were crucial for anthracycline-induced anticancer immune responses. ATP released by dying cancer cells recruited myeloid cells into tumors and stimulated the local differentiation of CD11c(+)CD11b(+)Ly6C(hi) cells. Such cells efficiently engulfed tumor antigens in situ and presented them to T lymphocytes, thus vaccinating mice, upon adoptive transfer, against a challenge with cancer cells. Manipulations preventing tumor infiltration by CD11c(+)CD11b(+)Ly6C(hi) cells, such as the local overexpression of ectonucleotidases, the blockade of purinergic receptors, or the neutralization of CD11b, abolished the immune system-dependent antitumor activity of anthracyclines. Our results identify a subset of tumor-infiltrating leukocytes as therapy-relevant antigen-presenting cells. PMID:23562161

  13. ImmunoChip study implicates antigen presentation to T cells in narcolepsy.

    Directory of Open Access Journals (Sweden)

    Juliette Faraco

    Full Text Available Recent advances in the identification of susceptibility genes and environmental exposures provide broad support for a post-infectious autoimmune basis for narcolepsy/hypocretin (orexin deficiency. We genotyped loci associated with other autoimmune and inflammatory diseases in 1,886 individuals with hypocretin-deficient narcolepsy and 10,421 controls, all of European ancestry, using a custom genotyping array (ImmunoChip. Three loci located outside the Human Leukocyte Antigen (HLA region on chromosome 6 were significantly associated with disease risk. In addition to a strong signal in the T cell receptor alpha (TRA@, variants in two additional narcolepsy loci, Cathepsin H (CTSH and Tumor necrosis factor (ligand superfamily member 4 (TNFSF4, also called OX40L, attained genome-wide significance. These findings underline the importance of antigen presentation by HLA Class II to T cells in the pathophysiology of this autoimmune disease.

  14. Modulation of innate antigen-presenting cell function by pre-patent schistosome infection.

    Directory of Open Access Journals (Sweden)

    Christine E Ferragine

    Full Text Available Schistosomes are intravascular helminths that infect over 200 million people worldwide. Deposition of eggs by adult schistosomes stimulates Th2 responses to egg antigens and induces granulomatous pathology that is a hallmark of schistosome infection. Paradoxically, schistosomes require host immune function for their development and reproduction and for egress of parasite eggs from the host. To identify potential mechanisms by which immune cells might influence parasite development prior to the onset of egg production, we assessed immune function in mice infected with developing schistosomes. We found that pre-patent schistosome infection is associated with a loss of T cell responsiveness to other antigens and is due to a diminution in the ability of innate antigen-presenting cells to stimulate T cells. Diminution of stimulatory capacity by schistosome worms specifically affected CD11b(+ cells and did not require concomitant adaptive responses. We could not find evidence for production of a diffusible inhibitor of T cells by innate cells from infected mice. Rather, inhibition of T cell responsiveness by accessory cells required cell contact and only occurred when cells from infected mice outnumbered competent APCs by more than 3∶1. Finally, we show that loss of T cell stimulatory capacity may in part be due to suppression of IL-12 expression during pre-patent schistosome infection. Modulation of CD4(+ T cell and APC function may be an aspect of host immune exploitation by schistosomes, as both cell types influence parasite development during pre-patent schistosome infection.

  15. Pollen-induced antigen presentation by mesenchymal stem cells and T cells from allergic rhinitis.

    Science.gov (United States)

    Desai, Mauli B; Gavrilova, Tatyana; Liu, Jianjun; Patel, Shyam A; Kartan, Saritha; Greco, Steven J; Capitle, Eugenio; Rameshwar, Pranela

    2013-10-01

    Mesenchymal stem cells (MSCs) are promising cellular suppressor of inflammation. This function of MSCs is partly due to their licensing by inflammatory mediators. In cases with reduced inflammation, MSCs could become immune-enhancer cells. MSCs can suppress the inflammatory response of antigen-challenged lymphocytes from allergic asthma. Although allergic rhinitis (AR) is also an inflammatory response, it is unclear if MSCs can exert similar suppression. This study investigated the immune effects (suppressor vs enhancer) of MSCs on allergen-stimulated lymphocytes from AR subjects (grass or weed allergy). In contrast to subjects with allergic asthma, MSCs caused a significant (Pcells (antigen-presenting cells (APCs)). This correlated with increased production of inflammatory cytokines from T cells, and increased expressions of major histocompatibility complex (MHC)-II and CD86 on MSCs. The specificity of APC function was demonstrated in APC assay using MSCs that were knocked down for the master regulator of MHC-II transcription, CIITA. The difference in the effects of MSCs on allergic asthma and AR could not be explained by the sensitivity to the allergen, based on skin tests. Thus, we deduced that the contrasting immune effects of MSCs for antigen-challenged lymphocytes on AR and allergic asthma could be disease specific. It is possible that the enhanced inflammation from asthma might be required to license the MSCs to become suppressor cells. This study underscores the need for robust preclinical studies to effectively translate MSCs for any inflammatory disorder. PMID:25505949

  16. 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

  17. Cross-presentation through langerin and DC-SIGN targeting requires different formulations of glycan-modified antigens

    NARCIS (Netherlands)

    Fehres, Cynthia M.; Kalay, Hakan; Bruijns, Sven C M; Musaafir, Sara A M; Ambrosini, Martino; Van Bloois, Louis; Van Vliet, Sandra J.; Storm, Gert; Garcia-Vallejo, Juan J.; Van Kooyk, Yvette

    2015-01-01

    Dendritic cells (DCs) and Langerhans cells (LC) are professional antigen presenting cells (APCs) that initiate humoral and cellular immune responses. Targeted delivery of antigen towards DC- or LC-specific receptors enhances vaccine efficacy. In this study, we compared the efficiency of glycan-based

  18. Cross-presentation through langerin and DC-SIGN targeting requires different formulation of glycan-modified antigens

    NARCIS (Netherlands)

    Fehres, Cynthia M.; Kalay, Hakan; Bruijns, Sven C.M.; Musaafir, Sara A.M.; Ambrosini, Martino; Bloois, van Louis; Vliet, van Sandra J.; Storm, Gert; Garcia-Vallejo, Juan J.; Kooyk, van Yvette

    2015-01-01

    Dendritic cells (DCs) and Langerhans cells (LC) are professional antigen presenting cells (APCs) that initiate humoral and cellular immune responses. Targeted delivery of antigen towards DC- or LC-specific receptors enhances vaccine efficacy. In this study, we compared the efficiency of glycan-based

  19. CD1d-mediated presentation of endogenous lipid antigens by adipocytes requires microsomal triglyceride transfer protein (MTP)

    DEFF Research Database (Denmark)

    Rakhshandehroo, Maryam; Gijzel, Sanne M W; Siersbæk, Rasmus;

    2014-01-01

    microsomal triglyceride transfer protein (MTP), which we show is also under the transcriptional regulation of C/EBPβ and -δ, as a novel player in the presentation of endogenous lipid antigens by adipocytes. Overall, our findings indicate that adipocytes can function as non-professional lipid antigen...

  20. Microsomal triglyceride transfer protein regulates endogenous and exogenous antigen presentation by group 1 CD1 molecules

    OpenAIRE

    Kaser, Arthur; Hava, David L.; Dougan, Stephanie K.; Chen, Zhangguo; Zeissig, Sebastian; Brenner, Michael B.; Blumberg, Richard S.

    2008-01-01

    Lipid antigens are presented to T cells by the non-polymorphic MHC class I-related CD1 molecules. Microsomal triglyceride transfer protein (MTP) is an endoplasmic reticulum (ER)-resident chaperone that has been shown to lipidate the group 2 CD1 molecule CD1d and thus to regulate its function. We now report that MTP also regulates the function of group 1 CD1 molecules CD1a, CD1b, and CD1c. Pharmacological inhibition of MTP in monocyte-derived dendritic cells and lymphoblastoid B cell lines tra...

  1. Survival and signaling changes in antigen presenting cell subsets after radiation

    Science.gov (United States)

    Parker, Jennifer Janell

    Radiation therapy is a widely used cancer treatment that has the potential to influence anti-tumor immune responses. Both myeloablative and non-myeloablative radiation are often used as part of preparatory regimens for hematopoetic stem cell transplantation, in combination with other chemotherapy or immuno-modulatory (e.g. Anti-thymocyte globulin (ATG)) therapies for both cytotoxic and immune modulatory purposes. However, the mechanisms responsible for the effect of radiation on antigen presenting cell (APC) responsiveness and radioresistance are poorly understood. The first studies described in this thesis were designed to identify and characterize early radiation-induced signaling changes in antigen presenting cells and to determine the effects of these signaling changes on APC receptor expression and function. The NFkappaB pathway in antigen presenting cells was chosen for study because it is activated by radiation in a wide range of other cell types and plays a vital role in the maintenance and regulation of the immune system. The effects of therapeutically relevant doses radiation (2 and 20 Gy) were compared at various timepoints in the human monocytic cell line (U937) using phospho-flow cytometry staining methods and cytometric analysis. These studies demonstrated that radiation-induced changes in the phosphorylation state of NFkappaB family members that were p53 independent. However, these changes were dependent upon activation of ATM in response to single or double-stranded breaks in DNA, as shown in experiments using an inhibitor of ATM and ATM siRNA knockdown U937 cells. In addition, studies examining the effect of radiation on co-stimulatory receptors with and without inhibition of the NFkappaB pathway via phospho-flow cytometry revealed that radiation-induced phosphorylation of NEMO promoted the activation and functional maturation of U937 cells. Furthermore, functional studies using both phospho-flow cytometry and/or mixed lymphocyte reactions to

  2. Papaya ringspot virus coat protein gene for antigen presentation Escherichia coli

    Czech Academy of Sciences Publication Activity Database

    Chatchen, S.; Juříček, Miloslav; Rueda, P.; Kertbundit, Sunee

    2006-01-01

    Roč. 39, č. 1 (2006), s. 16-21. ISSN 1225-8687 Grant ostatní: Thai Research Fund(TH) BT-B-06-PG-14-4503 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje Keywords : antigen presentation * canine parvo virus * epitope * papaya ringspot virus Subject RIV: EF - Botanics Impact factor: 1.465, year: 2006 http://www.jbmb.or.kr/view_article.php3?cont=jbmb&kid=174&mid=3&pid=3

  3. Inhibition of MHC class I-restricted antigen presentation by γ2-herpesviruses

    OpenAIRE

    Stevenson, Philip G.; Efstathiou, Stacey; Doherty, Peter C.; Lehner, Paul J.

    2000-01-01

    The γ-herpesviruses, in contrast to the α- and β-herpesviruses, are not known to inhibit antigen presentation to CD8+ cytotoxic T lymphocytes (CTLs) during lytic cycle replication. However, murine γ-herpesvirus 68 causes a chronic lytic infection in CD4+ T cell-deficient mice despite the persistence of a substantial CTL response, suggesting that CTL evasion occurs. Here we show that, distinct from host protein synthesis shutoff, γ-herpesvirus 68 down-regulates surface MHC class I expression o...

  4. Generation of competent bone marrow-derived antigen presenting cells from the deer mouse (Peromyscus maniculatus

    Directory of Open Access Journals (Sweden)

    Farrell Regina M

    2004-09-01

    Full Text Available Abstract Background Human infections with Sin Nombre virus (SNV and related New World hantaviruses often lead to hantavirus cardiopulmonary syndrome (HCPS, a sometimes fatal illness. Lungs of patients who die from HCPS exhibit cytokine-producing mononuclear infiltrates and pronounced pulmonary inflammation. Deer mice (Peromyscus maniculatus are the principal natural hosts of SNV, in which the virus establishes life-long persistence without conspicuous pathology. Little is known about the mechanisms SNV employs to evade the immune response of deer mice, and experimental examination of this question has been difficult because of a lack of methodologies for examining such responses during infection. One such deficiency is our inability to characterize T cell responses because susceptible syngeneic deer mice are not available. Results To solve this problem, we have developed an in vitro method of expanding and generating competent antigen presenting cells (APC from deer mouse bone marrow using commercially-available house mouse (Mus musculus granulocyte-macrophage colony stimulating factor. These cells are capable of processing and presenting soluble protein to antigen-specific autologous helper T cells in vitro. Inclusion of antigen-specific deer mouse antibody augments T cell stimulation, presumably through Fc receptor-mediated endocytosis. Conclusions The use of these APC has allowed us to dramatically expand deer mouse helper T cells in culture and should permit extensive characterization of T cell epitopes. Considering the evolutionary divergence between deer mice and house mice, it is probable that this method will be useful to other investigators using unconventional models of rodent-borne diseases.

  5. Cinnamon extract suppresses experimental colitis through modulation of antigen-presenting cells

    Institute of Scientific and Technical Information of China (English)

    Ho-Keun Kwon; Zee Yong Park; Sin-Hyeog Im; Ji-Sun Hwang; Choong-Gu Lee; Jae-Seon So; Anupama Sahoo; Chang-Rok Im; Won Kyung Jeon; Byoung Seob Ko; Sung Haeng Lee

    2011-01-01

    AIM:To investigate the anti-inflammatory effects of cinnamon extract and elucidate its mechanisms for targeting the function of antigen presenting cells. METHODS:Cinnamon extract was used to treat murine macrophage cell line (Raw 264.7),mouse primary antigen-presenting cells (APCs,MHCII+) and CD11c+ dendritic cells to analyze the effects of cinnamon extract on APC function.The mechanisms of action of cinnamon extract on APCs were investigated by analyzing cytokine production,and expression of MHC antigens and co-stimulatory molecules by quantitative real-time PCR and flow cytometry.In addition,the effect of cinnamon extract on antigen presentation capacity and APC-dependent T-cell differentiation were analyzed by [H3]-thymidine incorporation and cytokine analysis,respectively. To confirm the anti-inflammatory effects of cinnamon extract in vivo ,cinnamon or PBS was orally administered to mice for 20 d followed by induction of experimental colitis with 2,4,6 trinitrobenzenesulfonic acid.The protective effects of cinnamon extract against experimental colitis were measured by checking clinical symptoms,histological analysis and cytokine expression profiles in inflamed tissue. RESULTS:Treatment with cinnamon extract inhibited maturation of MHCII+ APCs or CD11c+ dendritic cells (DCs) by suppressing expression of co-stimulatory molecules (B7.1,B7.2,ICOS-L),MHCII and cyclooxygenase (COX)-2.Cinnamon extract induced regulatory DCs (rDCs) that produce low levels of pro-inflammatory cytokines [interleukin (IL)-1β,IL-6,IL-12,interferon (IFN)-γ and tumor necrosis factor (TNF)-α] while expressing high levels of immunoregulatory cytokines (IL-10 and transforming growth factor-β).In addition, rDCs generated by cinnamon extract inhibited APC-dependent T-cell proliferation,and converted CD4+ T cells into IL-10high CD4+ T cells.Furthermore,oral administration of cinnamon extract inhibited development and progression of intestinal colitis by inhibiting expression of COX-2 and pro

  6. Ly6C(+) monocyte efferocytosis and cross-presentation of cell-associated antigens.

    Science.gov (United States)

    Larson, S R; Atif, S M; Gibbings, S L; Thomas, S M; Prabagar, M G; Danhorn, T; Leach, S M; Henson, P M; Jakubzick, C V

    2016-06-01

    Recently it was shown that circulating Ly6C(+) monocytes traffic from tissue to the draining lymph nodes (LNs) with minimal alteration in their overall phenotype. Furthermore, in the steady state, Ly6C(+) monocytes are as abundant as classical dendritic cells (DCs) within the draining LNs, and even more abundant during inflammation. However, little is known about the functional roles of constitutively trafficking Ly6C(+) monocytes. In this study we investigated whether Ly6C(+) monocytes can efferocytose (acquire dying cells) and cross-present cell-associated antigen, a functional property particularly attributed to Batf3(+) DCs. We demonstrated that Ly6C(+) monocytes intrinsically efferocytose and cross-present cell-associated antigen to CD8(+) T cells. In addition, efferocytosis was enhanced upon direct activation of the Ly6C(+) monocytes through its corresponding TLRs, TLR4 and TLR7. However, only ligation of TLR7, and not TLR4, enhanced cross-presentation by Ly6C(+) monocytes. Overall, this study outlines two functional roles, among others, that Ly6C(+) monocytes have during an adaptive immune response. PMID:26990659

  7. Antigen presenting cells costimulatory signaling during pre-implantation pregnancy 

    Directory of Open Access Journals (Sweden)

    Anna Sławek

    2012-09-01

    Full Text Available  Success of pregnancy depends on many factors. Three phenomena inducing immune tolerance against semi-allogeneic conceptus may play a crucial role in the pre-implantation period of pregnancy: influence of sex hormones in sex cycle, presence of oocyte or embryo and the presence of semen in the female reproductive tract. On the other hand dendritic cells are the most effective antigen-presenting cells in regulation of immune phenomena and also are considered as potent participants in inducing immune tolerance in the pregnancy. They communicate with T cells in cell contact-dependent manner or via cytokines. During cell-cell contacts, costimulatory molecules play a key role and their expression is often dependent on cytokines milieu. Both costimulatory molecules and cytokines influence generation of T regulatory cells. Interactions of these molecules are closely related. In this paper we would like to pay attention to the importance of antigen presenting cells costimulatory potency in immune regulation during a pre-implantation period of pregnancy.

  8. HAM56 and CD68 antigen presenting cells surrounding a sarcoidal granulomatous tattoo

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2011-01-01

    Full Text Available Context : Tattoos are produced by introducing colorants of various compositions into the skin, either accidentally or for cosmetic purposes. Case Report: A 62-year-old male presented with a cosmetic tattoo and requested a total excision of the lesion. Dermatopathologic analysis of the excised tissue with hematoxylin and eosin examination, as well as immunohistochemistry was performed. H&E staining demonstrated classic histologic features of a tattoo. Utilizing immunohistochemistry, dermal histiocytic antigen presenting cells stained with HAM56 and CD68 antibodies; the staining was present surrounding the tattoo pigment. Conclusions : We identified two macrophage markers (HAM56 and CD68 surrounding dermal tattoo pigment. A minimal dermal inflammatory immune was noted to the tattoo pigment. Moreover, the immune response and/or tolerance to tattoos is not well characterized. We suggest that tattoo materials and techniques could be utilized in therapeutic delivery for diseases such recessive dystrophic epidermolysis bullosa, potentially preventing immune rejection of gene therapy agents.

  9. Role of HLA class I antigens in the development of psoriatic arthritis and its clinical presentation

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    Irina Aleksandrovna Troshkina

    2012-01-01

    Full Text Available Objective: to investigate the association of HLA Class I antigens with the predisposition to psoriatic arthritis (PsA and the severity and types of articular syndrome in PsA. Subjects and methods. The investigation enrolled 99 patients (56 females and 43 males aged 43.5+13 years with PA with a median duration of 2 (range 0.8-10 years. An oligoarthritic type was observed in 28 patients, polyarthritic, distal, and spondyloarthritic types were present in 28, 39, and 10 patients, respectively. Two patient groups were formed according to the age at onset of psoriasis: 1 71 patients aged less than 40 years and 2 23 patients aged over 40 years. Results. As compared with the control group, the patients with PsA were found to have a higher frequency of HLA-B13 (odds ratio [OR] 2.72; p < 0.004, HLA-В16 (OR 3.95; p < 0.0001, and HLA-B27 (OR 3.2; p < 0.003. There was an association of the types of joint injury with HLA antigens: the distal type with HLA-B13 (OR 3.38; p < 0.02 and HLA-В16 (OR 3.95; p < 0.01, the polyarthritic type with HLA-В16 (OR 5.90; p < 0.0001 and HLA-B27 (OR 3.26; p < 0.01, and the spondyloarthritic type with HLA-B27 (OR 6.32; p < 0.001. The young onset of psoriasis was associated with HLA-B13 (OR 3.29; p < 0.001. The detection rate of the B38 antigen (the subtype of HLA-B16 was higher in all X-ray stages of PsA and was 16.4% in Stages I-IIA, 25% in Stage IIB, and 40.9% in Stages III-IV versus 8.7% in the control group, the magnitude of the association being increased with the higher degree of joint destruction. Conclusion. The detailed analysis of the investigation revealed that HLA system antigens were differently involved in the development of PsA and clinical types of articular syndrome.

  10. 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.

  11. Cross-presentation through langerin and DC-SIGN targeting requires different formulations of glycan-modified antigens.

    Science.gov (United States)

    Fehres, Cynthia M; Kalay, Hakan; Bruijns, Sven C M; Musaafir, Sara A M; Ambrosini, Martino; van Bloois, Louis; van Vliet, Sandra J; Storm, Gert; Garcia-Vallejo, Juan J; van Kooyk, Yvette

    2015-04-10

    Dendritic cells (DCs) and Langerhans cells (LC) are professional antigen presenting cells (APCs) that initiate humoral and cellular immune responses. Targeted delivery of antigen towards DC- or LC-specific receptors enhances vaccine efficacy. In this study, we compared the efficiency of glycan-based antigen targeting to both the human DC-specific C-type lectin receptor (CLR) DC-SIGN and the LC-specific CLR langerin. Since DC-SIGN and langerin are able to recognize the difucosylated oligosaccharide Lewis Y (Le(Y)), we prepared neoglycoconjugates bearing this glycan epitope to allow targeting of both lectins. Le(Y)-modified liposomes, with an approximate diameter of 200nm, were significantly endocytosed by DC-SIGN(+) DCs and mediated efficient antigen presentation to CD4(+) and CD8(+) T cells. Surprisingly, although langerin bound to Le(Y)-modified liposomes, LCs exposed to Le(Y)-modified liposomes could not endocytose liposomes nor mediate antigen presentation to T cells. However, LCs mediated an enhanced cross-presentation when antigen was delivered through langerin using Le(Y)-modified synthetic long peptides. In contrast, Le(Y)-modified synthetic long peptides were recognized by DC-SIGN, but did not trigger antigen internalization nor antigen cross-presentation. These data demonstrate that langerin and DC-SIGN have different size requirements for antigen uptake. Although using glycans remains an interesting option in the design of anti-cancer vaccines targeting multiple CLRs, aspects such as molecule size and conformation need to be taken in consideration. PMID:25656175

  12. Aluminum hydroxide adjuvant induces macrophage differentiation towards a specialized antigen-presenting cell type.

    Science.gov (United States)

    Rimaniol, Anne-Cécile; Gras, Gabriel; Verdier, François; Capel, Francis; Grigoriev, Vladimir B; Porcheray, Fabrice; Sauzeat, Elisabeth; Fournier, Jean-Guy; Clayette, Pascal; Siegrist, Claire-Anne; Dormont, Dominique

    2004-08-13

    Aluminum hydroxide (AlOOH) has been used for many years as a vaccine adjuvant, but little is known about its mechanism of action. We investigated in this study the in vitro effect of aluminum hydroxide adjuvant on isolated macrophages. We showed that AlOOH-stimulated macrophages contain large and persistent intracellular crystalline inclusions, a characteristic property of muscle infiltrated macrophages described in animal models of vaccine injection, as well as in the recently described macrophagic myofasciitis (MMF) histological reaction in humans. AlOOH-loaded macrophages exhibited phenotypical and functional modifications, as they expressed the classical markers of myeloid dendritic cells (HLA-DR(high)/CD86(high)/CD83(+)/CD1a(-)/CD14(-)) and displayed potent ability to induce MHC-II-restricted antigen specific memory responses, but kept a macrophage morphology. This suggests a key role of macrophages, in the reaction to AlOOH-adjuvanted vaccines and these mature antigen-presenting macrophages may therefore be of particular importance in the establishment of memory responses and in vaccination mechanisms leading to long-lasting protection. PMID:15297065

  13. Targeting tumor-associated antigens to the MHC class I presentation pathway.

    Science.gov (United States)

    Gross, G; Margalit, A

    2007-06-01

    There is little doubt that cytotoxic T lymphocytes (CTLs) can kill tumor cells in-vivo. However, most CTL-inducing immunization protocols examined so far in cancer patients have yielded only limited clinical benefits, underscoring the urge to improve current approaches for the effective induction of tumor-reactive CTLs. The tumor side of the immunological frontline is armed with large masses, high mutability and an arsenal of immune evasion and suppression mechanisms. Accordingly, the confronting CTLs should come in large numbers, recognize an assortment of MHC class I (MHC-I) bound tumor-associated peptides and be brought into action under effective immunostimulatory conditions. Naïve CTLs are activated to become effector cells in secondary lymphoid organs, following their productive encounter with MHC-I-bound peptides at the surface of dendritic cells (DCs). Therefore, many cancer vaccines under development focus on the optimization of peptide presentation by DCs at this critical stage. The elucidation of discrete steps and the subsequent identification of inherent bottlenecks in the MHC-I antigen presentation pathway have fueled elaborate efforts to enhance vaccine efficacy by the rational targeting of proteins or peptides, formulated into these vaccines, to this pathway. Protein- and gene-based strategies are accordingly devised to deliver tumor-associated peptides to selected cellular compartments, which are essential for the generation of functional CTL ligands. Many of these strategies target the conventional, endogenous route, while others harness the unique pathways that enable DCs to present exogenous antigens, known as cross-presentation. Here we dissect the intricate machinery that produces CTL ligands and examine how knowledge-based cancer vaccines can target the sequence of workstations, biochemical utensils and molecular intermediates comprising this production line. PMID:17584150

  14. An evolutionary analysis of antigen processing and presentation across different timescales reveals pervasive selection.

    Directory of Open Access Journals (Sweden)

    Diego Forni

    2014-03-01

    Full Text Available The antigenic repertoire presented by MHC molecules is generated by the antigen processing and presentation (APP pathway. We analyzed the evolutionary history of 45 genes involved in APP at the inter- and intra-species level. Results showed that 11 genes evolved adaptively in mammals. Several positively selected sites involve positions of fundamental importance to the protein function (e.g. the TAP1 peptide-binding domains, the sugar binding interface of langerin, and the CD1D trafficking signal region. In CYBB, all selected sites cluster in two loops protruding into the endosomal lumen; analysis of missense mutations responsible for chronic granulomatous disease (CGD showed the action of different selective forces on the very same gene region, as most CGD substitutions involve aminoacid positions that are conserved in all mammals. As for ERAP2, different computational methods indicated that positive selection has driven the recurrent appearance of protein-destabilizing variants during mammalian evolution. Application of a population-genetics phylogenetics approach showed that purifying selection represented a major force acting on some APP components (e.g. immunoproteasome subunits and chaperones and allowed identification of positive selection events in the human lineage. We also investigated the evolutionary history of APP genes in human populations by developing a new approach that uses several different tests to identify the selection target, and that integrates low-coverage whole-genome sequencing data with Sanger sequencing. This analysis revealed that 9 APP genes underwent local adaptation in human populations. Most positive selection targets are located within noncoding regions with regulatory function in myeloid cells or act as expression quantitative trait loci. Conversely, balancing selection targeted nonsynonymous variants in TAP1 and CD207 (langerin. Finally, we suggest that selected variants in PSMB10 and CD207 contribute to human

  15. An evolutionary analysis of antigen processing and presentation across different timescales reveals pervasive selection.

    Science.gov (United States)

    Forni, Diego; Cagliani, Rachele; Tresoldi, Claudia; Pozzoli, Uberto; De Gioia, Luca; Filippi, Giulia; Riva, Stefania; Menozzi, Giorgia; Colleoni, Marta; Biasin, Mara; Lo Caputo, Sergio; Mazzotta, Francesco; Comi, Giacomo P; Bresolin, Nereo; Clerici, Mario; Sironi, Manuela

    2014-03-01

    The antigenic repertoire presented by MHC molecules is generated by the antigen processing and presentation (APP) pathway. We analyzed the evolutionary history of 45 genes involved in APP at the inter- and intra-species level. Results showed that 11 genes evolved adaptively in mammals. Several positively selected sites involve positions of fundamental importance to the protein function (e.g. the TAP1 peptide-binding domains, the sugar binding interface of langerin, and the CD1D trafficking signal region). In CYBB, all selected sites cluster in two loops protruding into the endosomal lumen; analysis of missense mutations responsible for chronic granulomatous disease (CGD) showed the action of different selective forces on the very same gene region, as most CGD substitutions involve aminoacid positions that are conserved in all mammals. As for ERAP2, different computational methods indicated that positive selection has driven the recurrent appearance of protein-destabilizing variants during mammalian evolution. Application of a population-genetics phylogenetics approach showed that purifying selection represented a major force acting on some APP components (e.g. immunoproteasome subunits and chaperones) and allowed identification of positive selection events in the human lineage. We also investigated the evolutionary history of APP genes in human populations by developing a new approach that uses several different tests to identify the selection target, and that integrates low-coverage whole-genome sequencing data with Sanger sequencing. This analysis revealed that 9 APP genes underwent local adaptation in human populations. Most positive selection targets are located within noncoding regions with regulatory function in myeloid cells or act as expression quantitative trait loci. Conversely, balancing selection targeted nonsynonymous variants in TAP1 and CD207 (langerin). Finally, we suggest that selected variants in PSMB10 and CD207 contribute to human phenotypes

  16. Engineered nanomaterials cause cytotoxicity and activation on mouse antigen presenting cells

    International Nuclear Information System (INIS)

    Nanomaterials improve everyday products but their safety for human health is poorly known. In this study we explored immunological effects of five different nanomaterials on antigen presenting cells (APC) in vitro. Nanomaterials studied were rutile titanium dioxide (TiO2), amorphous silica-coated rutile titanium dioxide (TiO2-silica), zinc oxide (ZnO), single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT). APCs included mouse macrophages (RAW 264.7 cell line) and murine bone marrow-derived dendritic cells (bmDC). All studied particles were cytotoxic to bmDCs, and ZnO, TiO2 and TiO2-silica-induced dose-dependently cell death also in macrophages. ZnO had the most drastic immunological effects leading to high expression of proinflammatory cytokine, IL-1β, and enhanced production of neutrophil chemoattractant CXCL-9 on both cell types. TiO2 and TiO2-silica stimulated the expression of IL-6, MIP-1α and TNF-α in macrophages, and increased their maturation, antigen presentation and co-stimulation activity. In contrast, SWCNT or MWCNT did not seem to have any significant immunological effects on the cell types studied suggesting that APCs might not be the target cells for carbon nanotubes. Due to diverse effects on different nanomaterials on immune cells we suggest that each new nanomaterial should be extensively studied in vitro and in vivo for risk assessment before their use in final products.

  17. Seoul virus suppresses NF-κB-mediated inflammatory responses of antigen presenting cells from Norway rats

    OpenAIRE

    Au, Rebecca Y.; Jedlicka, Anne E.; Li, Wei; Pekosz, Andrew; Klein, Sabra L.

    2010-01-01

    Hantavirus infection reduces antiviral defenses, increases regulatory responses, and causes persistent infection in rodent hosts. To address whether hantaviruses alter the maturation and functional activity of antigen presenting cells (APCs), rat bone marrow-derived dendritic cells (BMDCs) and macrophages (BMDMs) were generated and infected with Seoul virus (SEOV) or stimulated with TLR ligands. SEOV infected both DCs and macrophages, but copies of viral RNA, viral antigen, and infectious vir...

  18. Antigen uptake, processing and presentation to T-cells is still functional in dendritic cells surviving photodynamic treatment

    International Nuclear Information System (INIS)

    Full text: The effect of photodynamic therapy (PDT) on anti-tumoral immune reactions is still discussed controversially. Several studies have demonstrated that PDT is able to activate immune reactions against tumor antigens. However, there is also evidence that PDT exerts immunosuppressive effects. Dendritic cells (DC) are professional antigen presenting cells and play an important role in, both, the induction of immune reactions as well as the induction and maintenance of immunologic tolerance. Therefore, we investigated the effect of hypericin-mediated PDT on the capability of bone marrow-derived DC for antigen uptake, processing and presentation to CD4+ T lymphocytes. Using beta-galactosidase as model antigens we found that, under sublethal PDT conditions, antigen is still incorporated and degraded by surviving DC. PDT-treated DC, in the presence of beta-galactosidase, were still able to re-activate splenic T cells from immunized but not from naive mice. Similarly, naive allogenic T cells were activated in an antigen-independent manner by PDT-treated DC, albeit at lower efficiency as compared to untreated DC. Based on these data, we hypothesize that DC localized in PDT-treated tumor lesions could play a role in the regulation of anti-tumor immune reactions. (author)

  19. Antigen Expression on Blast Cells and Hematological Parameters at Presentation in Acute Lymphoblastic Leukemia Patients

    International Nuclear Information System (INIS)

    Objective: To analyze the expression of various antigens on the leukemic blasts and to determine the hematological parameters, in Acute Lymphoblastic Leukemia (ALL) patients at presentation. Study Design: Observational study. Place and Duration of Study: King Edward Medical University, Lahore and Hameed Latif Hospital, Lahore, from February 2013 to March 2014. Methodology: A total of 50 newly diagnosed and untreated patients of ALL were selected from Mayo Hospital and Hameed Latif Hospital. These patients included both genders and all age groups. Hemoglobin, total leukocyte count and platelet count were determined on hematology analyser-Sysmex-Kx-2I. Blast cell percentage was estimated on Giemsa stained blood smears. Immuno phenotyping was done on bone marrow samples by 5 colour flow cytometery on Beckman Counter Navious Flow cytometer. An acute leukemia panel of 23 antibodies was used. The data was entered and analyzed in SPSS version 22. Results: Of the 50 ALL patients, 36 (72 percentage) were B-ALL and 14 (28 percentage) T-ALL. There were 18 (36 percentage) children and 32 (64 percentage) adults. T-ALL included 22 percentage of the childhood and 31 percentage of the adult cases. Immuno phenotypic analysis showed that CD19, CD79a and CD20 were B-lineage specific markers whereas cCD3, CD3 and CD5 were T-lineage specific. CD10 was the most sensitive marker for B-ALL and CD7 was the most sensitive marker of T-ALL. TdT was expressed in 92 percentage B-ALL and 71 percentage T-ALL cases, CD34 in 58 percentage and 43 percentage cases and CD45 in 83 percentage and 100 percentage respectively. High leukocyte count (> 50 x 109/L) was present in 58 percentage cases. Hemoglobin was < 10 g/dl in 74 percentage patients and platelet count was below 20 x 109/Lin 12 percentage patients. Leukocyte count, hemoglobin, platelet count and blast cell percentage did not show a significant difference in the two ALL immuno types. Conclusion: The frequency of T-ALL is higher in childhood

  20. Regulation of Hemichannels and Gap Junction Channels by Cytokines in Antigen-Presenting Cells

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    Pablo J. Sáez

    2014-01-01

    Full Text Available Autocrine and paracrine signals coordinate responses of several cell types of the immune system that provide efficient protection against different challenges. Antigen-presenting cells (APCs coordinate activation of this system via homocellular and heterocellular interactions. Cytokines constitute chemical intercellular signals among immune cells and might promote pro- or anti-inflammatory effects. During the last two decades, two membrane pathways for intercellular communication have been demonstrated in cells of the immune system. They are called hemichannels (HCs and gap junction channels (GJCs and provide new insights into the mechanisms of the orchestrated response of immune cells. GJCs and HCs are permeable to ions and small molecules, including signaling molecules. The direct intercellular transfer between contacting cells can be mediated by GJCs, whereas the release to or uptake from the extracellular milieu can be mediated by HCs. GJCs and HCs can be constituted by two protein families: connexins (Cxs or pannexins (Panxs, which are present in almost all APCs, being Cx43 and Panx1 the most ubiquitous members of each protein family. In this review, we focus on the effects of different cytokines on the intercellular communication mediated by HCs and GJCs in APCs and their impact on purinergic signaling.

  1. Formaldehyde treatment of proteins can constrain presentation to T cells by limiting antigen processing.

    OpenAIRE

    Di Tommaso, A; De Magistris, M T; Bugnoli, M.; Marsili, I; Rappuoli, R; Abrignani, S.

    1994-01-01

    Proteins to be used as vaccines are frequently treated with formaldehyde, although little is known about the effects of this treatment on protein antigenicity. To investigate the effect of formaldehyde treatment on antigen recognition by T cells, we compared the in vitro T-cell response to proteins that have been formaldehyde treated with the response to untreated proteins. We found that peripheral blood mononuclear cells from individuals vaccinated with three formaldehyde-treated proteins (p...

  2. Genome-wide promoter analysis of histone modifications in human monocyte-derived antigen presenting cells

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    Peterson Hedi

    2010-11-01

    Full Text Available Abstract Background Monocyte-derived macrophages and dendritic cells (DCs are important in inflammatory processes and are often used for immunotherapeutic approaches. Blood monocytes can be differentiated into macrophages and DCs, which is accompanied with transcriptional changes in many genes, including chemokines and cell surface markers. Results To study the chromatin modifications associated with this differentiation, we performed a genome wide analysis of histone H3 trimethylation on lysine 4 (H3K4me3 and 27 (H3K27me3 as well as acetylation of H3 lysines (AcH3 in promoter regions. We report that both H3K4me3 and AcH3 marks significantly correlate with transcriptionally active genes whereas H3K27me3 mark is associated with inactive gene promoters. During differentiation, the H3K4me3 levels decreased on monocyte-specific CD14, CCR2 and CX3CR1 but increased on DC-specific TM7SF4/DC-STAMP, TREM2 and CD209/DC-SIGN genes. Genes associated with phagocytosis and antigen presentation were marked by H3K4me3 modifications. We also report that H3K4me3 levels on clustered chemokine and surface marker genes often correlate with transcriptional activity. Conclusion Our results provide a basis for further functional correlations between gene expression and histone modifications in monocyte-derived macrophages and DCs.

  3. Role of antigen presentation in the production of pro-inflammatory cytokines in obese adipose tissue.

    Science.gov (United States)

    Majdoubi, Abdelilah; Kishta, Osama A; Thibodeau, Jacques

    2016-06-01

    Type II diabetes regroups different physiological anomalies that ultimately lead to low-grade chronic inflammation, insulin resistance and loss of pancreatic β-cells. Obesity is one of the best examples of such a condition that can develop into Metabolic Syndrome, causing serious health problems of great socio-economic consequences. The pathological outcome of obesity has a genetic basis and depends on the delicate balance between pro- and anti-inflammatory effectors of the immune system. The causal link between obesity and inflammation is well established. While innate immunity plays a key role in the development of a pro-inflammatory state in obese adipose tissues, it has now become clear that adaptive immune cells are also involved and participate in the cascade of events that lead to metabolic perturbations. The efficacy of some immunotherapeutic protocols in reducing the symptoms of obesity-driven metabolic syndrome in mice implicated all arms of the immune response. Recently, the production of pathogenic immunoglobulins and pro-inflammatory cytokines by B and T lymphocytes suggested an auto-immune basis for the establishment of a non-healthy obese state. Understanding the cellular landscape of obese adipose tissues and how immune cells sustain chronic inflammation holds the key to the development of targeted therapies. In this review, we emphasize the role of antigen-presenting cells and MHC molecules in obese adipose tissue and the general contribution of the adaptive arm of the immune system in inflammation-induced insulin resistance. PMID:26854212

  4. Antigen presenting cell abnormalities in the Cln3(-/-) mouse model of juvenile neuronal ceroid lipofuscinosis.

    Science.gov (United States)

    Hersrud, Samantha L; Kovács, Attila D; Pearce, David A

    2016-07-01

    Mutations of the CLN3 gene lead to juvenile neuronal ceroid lipofuscinosis (JNCL), an autosomal recessive lysosomal storage disorder that causes progressive neurodegeneration in children and adolescents. There is evidence of immune system involvement in pathology that has been only minimally investigated. We characterized bone marrow stem cell-derived antigen presenting cells (APCs), peritoneal macrophages, and leukocytes from spleen and blood, harvested from the Cln3(-/-) mouse model of JNCL. We detected dramatically elevated CD11c surface levels and increased total CD11c protein in Cln3(-/-) cell samples compared to wild type. This phenotype was specific to APCs and also to a loss of CLN3, as surface levels did not differ from wild type in other leukocyte subtypes nor in cells from two other NCL mouse models. Subcellularly, CD11c was localized to lipid rafts, indicating that perturbation of surface levels is attributable to derangement of raft dynamics, which has previously been shown in Cln3 mutant cells. Interrogation of APC function revealed that Cln3(-/-) cells have increased adhesiveness to CD11c ligands as well as an abnormal secretory pattern that closely mimics what has been previously reported for Cln3 mutant microglia. Our results show that CLN3 deficiency alters APCs, which can be a major contributor to the autoimmune response in JNCL. PMID:27101989

  5. A novel approach for reliable detection of cathepsin S activities in mouse antigen presenting cells.

    Science.gov (United States)

    Steimle, Alex; Kalbacher, Hubert; Maurer, Andreas; Beifuss, Brigitte; Bender, Annika; Schäfer, Andrea; Müller, Ricarda; Autenrieth, Ingo B; Frick, Julia-Stefanie

    2016-05-01

    Cathepsin S (CTSS) is a eukaryotic protease mostly expressed in professional antigen presenting cells (APCs). Since CTSS activity regulation plays a role in the pathogenesis of various autoimmune diseases like multiple sclerosis, atherosclerosis, Sjögren's syndrome and psoriasis as well as in cancer progression, there is an ongoing interest in the reliable detection of cathepsin S activity. Various applications have been invented for specific detection of this enzyme. However, most of them have only been shown to be suitable for human samples, do not deliver quantitative results or the experimental procedure requires technical equipment that is not commonly available in a standard laboratory. We have tested a fluorogen substrate, Mca-GRWPPMGLPWE-Lys(Dnp)-DArg-NH2, that has been described to specifically detect CTSS activities in human APCs for its potential use for mouse samples. We have modified the protocol and thereby offer a cheap, easy, reproducible and quick activity assay to detect CTSS activities in mouse APCs. Since most of basic research on CTSS is performed in mice, this method closes a gap and offers a possibility for reliable and quantitative CTSS activity detection that can be performed in almost every laboratory. PMID:26899824

  6. Interaction between antigen presenting cells and autoreactive T cells derived from BXSB mice with murine lupus

    Institute of Scientific and Technical Information of China (English)

    Peng Yang; Bo Li; Ping Lv; Yan Zhang; XiaoMing Gao

    2007-01-01

    Systemic lupus erythematosus (SLE) is a typical autoimmune disease involving multiple systems and organs. Ample evidence suggests that autoreactive T cells play a pivotal role in the development of this autoimmune disorder. This study was undertaken to investigate the mechanisms of interaction between antigen presenting cells (APCs) and an autoreactive T cell (ATL1) clone obtained from lupus-prone BXSB mice. ATL1 cells, either before or after γ-ray irradiation, were able to activate naive B cells, as determined by B cell proliferation assays. Macrophages from BXSB mice were able to stimulate the proliferation of resting ATL1 cells at a responder/stimulator (R/S) ratio of 1/2.5. Dendritic cells (DCs) were much more powerful stimulators for ATL1 cells on a per cell basis. The T cell stimulating ability of macrophages and B cells, but not DCs, was sensitive toγ-ray irradiation. Monoclonal antibodies against mouse MHC-Ⅱand CD4 were able to block DC-mediated stimulation of ATL1 proliferation, indicating cognate recognition between ATL1 and APCs. Our data suggest that positive feedback loops involving macrophages, B cells and autoreactive T cells may play a pivotal role in keeping the momentum of autoimmune responses leading to autoimmune diseases.

  7. Mass spectrometry of human leukocyte antigen class I peptidomes reveals strong effects of protein abundance and turnover on antigen presentation

    DEFF Research Database (Denmark)

    Bassani-Sternberg, Michal; Pletscher-Frankild, Sune; Jensen, Lars Juhl; Mann, Matthias

    2015-01-01

    HLA class I molecules reflect the health state of cells to cytotoxic T cells by presenting a repertoire of endogenously derived peptides. However, the extent to which the proteome shapes the peptidome is still largely unknown. Here we present a high-throughput mass-spectrometry-based workflow that...

  8. A novel strategy to improve antigen presentation for active immunotherapy in cancer. Fusion of the human papillomavirus type 16 E7 antigen to a cell penetrating peptide

    International Nuclear Information System (INIS)

    Facilitating the delivery of exogenous antigens to antigen-presenting cells, ensuing processing and presentation via the major histocompatibility complex class I and induction of an effective immune response are fundamental for an effective therapeutic cancer vaccine. In this regard, we propose the use of cell-penetrating peptides fused to a tumor antigen. To demonstrate this concept we designed a fusion protein comprising a novel cell-penetrating and immunostimulatory peptide corresponding to residues 32 to 51 of the Limulus anti-lipopolysaccharide factor protein (LALF32-51) linked to human papillomavirus 16 E7 antigen (LALF32-51-E7). In this work, we demonstrated that the immunization with LALF32-51-E7 using the TC-1 mouse model induces a potent and long-lasting anti-tumor response supported on an effective E7-specific CD8+T-cell response. The finding that therapeutic immunization with LALF32-51 or E7 alone, or an admixture of LALF32-51 and E7, does not induce significant tumor reduction indicates that covalent linkage between LALF32-51 and E7 is required for the anti-tumor effect. These results support the use of this novel cell-penetrating peptide as an efficient means for delivering therapeutic targets into cellular compartments with the induction of a cytotoxic CD8+T lymphocyte immune response. This approach is promissory for the treatment of tumors associated with the human papillomavirus 16, which is responsible for the 50% of cervical cancer cases worldwide and other malignancies. Furthermore, protein-based vaccines can circumvent the major histocompatibility complex specificity limitation associated with peptide vaccines providing a greater extent in their application

  9. Antigen presenting cell-selective drug delivery by glycan-decorated nanocarriers.

    Science.gov (United States)

    Frenz, Theresa; Grabski, Elena; Durán, Verónica; Hozsa, Constantin; Stępczyńska, Anna; Furch, Marcus; Gieseler, Robert K; Kalinke, Ulrich

    2015-09-01

    Targeted drug delivery systems hold promise for selective provision of active compounds to distinct tissues or cell subsets. Thus, locally enhanced drug concentrations are obtained that would confer improved efficacy. As a consequence adverse effects should be diminished, as innocent bystander cells are less affected. Currently, several controlled drug delivery systems based on diverse materials are being developed. Some systems exhibit material-associated toxic effects and/or show low drug loading capacity. In contrast, liposomal nanocarriers are particularly favorable because they are well tolerated, poorly immunogenic, can be produced in defined sizes, and offer a reasonable payload capacity. Compared with other immune cells, professional antigen-presenting cells (APCs) demonstrate enhanced liposome uptake mediated by macropinocytosis, phagocytosis and presumably also by clathrin- and caveolae-mediated endocytosis. In order to further enhance the targeting efficacy toward APCs, receptor-mediated uptake appears advisable. Since APC subsets generally do not express single linage-specific receptors, members of the C-type lectin receptor (CLR) family are compelling targets. Examples of CLR expressed by APCs include DEC-205 (CD205) expressed by myeloid dendritic cells (DC) and monocytes, the mannose receptor C type 1 (MR, CD206) expressed by DC, monocytes and macrophages, DC-SIGN (CD209) expressed by DC, and several others. These receptors bind glycans, which are typically displayed by pathogens and thus support pathogen uptake and endocytosis. Further research will elucidate whether glycan-decorated liposomes will not only enhance APCs targeting but also enable preferential delivery of their payload to discrete subcellular compartments. PMID:25701806

  10. Antigen presentation by small intestinal epithelial cells uniquely enhances IFN-γ secretion from CD4+ intestinal intraepithelial lymphocytes

    International Nuclear Information System (INIS)

    Highlights: •Small intestinal epithelial cells (sIECs). •sIECs are able to induce antigen specific proliferation of CD4+ IELs. •sIECs induce markedly enhanced IFN-γ secretion by CD4+ IELs. •Induction of enhanced IFN-γ secretion by sIECs is uniquely observed in CD4+ IELs. -- Abstract: Small intestinal epithelial cells (sIECs) express major histocompatibility complex class II molecules even in a normal condition, and are known to function as antigen presenting cells (APCs) at least in vitro. These findings raised the possibility that sIECs play an important role in inducing immune responses against luminal antigens, especially those of intestinal intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs). We herein showed that antigenic stimulation with sIECs induced markedly greater secretion of interferon-gamma (IFN-γ) by CD4+ IELs, but not interleukin (IL)-4, IL-10 and IL-17 although the proliferative response was prominently lower than that with T cell-depleted splenic APCs. In contrast, no enhanced IFN-γ secretion by CD4+ LPLs and primed splenic CD4+ T cells was observed when stimulated with sIECs. Taken together, these results suggest that sIECs uniquely activate CD4+ IELs and induce remarkable IFN-γ secretion upon antigenic stimulation in vivo

  11. Antigen presentation by small intestinal epithelial cells uniquely enhances IFN-γ secretion from CD4{sup +} intestinal intraepithelial lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hatano, Ryo; Yamada, Kiyoshi; Iwamoto, Taku; Maeda, Nana; Emoto, Tetsuro; Shimizu, Makoto; Totsuka, Mamoru, E-mail: atotuka@mail.ecc.u-tokyo.ac.jp

    2013-06-14

    Highlights: •Small intestinal epithelial cells (sIECs). •sIECs are able to induce antigen specific proliferation of CD4{sup +} IELs. •sIECs induce markedly enhanced IFN-γ secretion by CD4{sup +} IELs. •Induction of enhanced IFN-γ secretion by sIECs is uniquely observed in CD4{sup +} IELs. -- Abstract: Small intestinal epithelial cells (sIECs) express major histocompatibility complex class II molecules even in a normal condition, and are known to function as antigen presenting cells (APCs) at least in vitro. These findings raised the possibility that sIECs play an important role in inducing immune responses against luminal antigens, especially those of intestinal intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs). We herein showed that antigenic stimulation with sIECs induced markedly greater secretion of interferon-gamma (IFN-γ) by CD4{sup +} IELs, but not interleukin (IL)-4, IL-10 and IL-17 although the proliferative response was prominently lower than that with T cell-depleted splenic APCs. In contrast, no enhanced IFN-γ secretion by CD4{sup +} LPLs and primed splenic CD4{sup +} T cells was observed when stimulated with sIECs. Taken together, these results suggest that sIECs uniquely activate CD4{sup +} IELs and induce remarkable IFN-γ secretion upon antigenic stimulation in vivo.

  12. Shedding light on anti-estrogen resistance and antigen presentation through biophysical techniques

    NARCIS (Netherlands)

    Zwart, Willem Teunis

    2009-01-01

    This thesis is composed of two parts part one: The study on anti-estrogen resistance and defining criteria a cell has to meet in order to become resistant to anti-estrogenic compounds. part two: the study of antigen-loading, vesicle positioning and costimulation.

  13. Use of the Recombinant Particles of Potato Virus a (PVA) for Presentation of Foreign Antigens

    Czech Academy of Sciences Publication Activity Database

    Moravec, Tomáš; Čeřovská, Noemi; Velemínský, Jiří

    Aschersleben : International Society of Plant Pathology, 2002, s. 103. [International Plant Virus Epidemiology Symposium /8./.. Aschersleben (DE), 12.03.2002-17.03.2002] Institutional research plan: CEZ:AV0Z5038910 Keywords : recombinant particles * potato virus (PVA) * antigens Subject RIV: EB - Genetics ; Molecular Biology

  14. IgE/FcεRI-Mediated Antigen Cross-Presentation by Dendritic Cells Enhances Anti-Tumor Immune Responses

    Directory of Open Access Journals (Sweden)

    Barbara Platzer

    2015-03-01

    Full Text Available Epidemiologic studies discovered an inverse association between immunoglobulin E (IgE-mediated allergies and cancer, implying tumor-protective properties of IgE. However, the underlying immunologic mechanisms remain poorly understood. Antigen cross-presentation by dendritic cells (DCs is of key importance for anti-tumor immunity because it induces the generation of cytotoxic CD8+ T lymphocytes (CTLs with specificity for tumor antigens. We demonstrate that DCs use IgE and FcεRI, the high-affinity IgE receptor, for cross-presentation and priming of CTLs in response to free soluble antigen at low doses. Importantly, IgE/FcεRI-mediated cross-presentation is a distinct receptor-mediated pathway because it does not require MyD88 signals or IL-12 induction in DCs. Using passive immunization with tumor antigen-specific IgE and DC-based vaccination experiments, we demonstrate that IgE-mediated cross-presentation significantly improves anti-tumor immunity and induces memory responses in vivo. Our findings suggest a cellular mechanism for the tumor-protective features of IgE and expand the known physiological functions of this immunoglobulin.

  15. Hepatitis B virus-like particles access major histocompatibility class I and II antigen presentation pathways in primary dendritic cells.

    Science.gov (United States)

    Moffat, Jessica M; Cheong, Wan-Shoo; Villadangos, José A; Mintern, Justine D; Netter, Hans J

    2013-04-26

    Virus-like particles (VLPs) represent high density displays of viral proteins that efficiently trigger immunity. VLPs composed of the small hepatitis B virus envelope protein (HBsAgS) are useful vaccine platforms that induce humoral and cellular immune responses. Notably, however, some studies suggest HBsAgS VLPs impair dendritic cell (DC) function. Here we investigated HBsAgS VLP interaction with DC subsets and antigen access to major histocompatibility complex (MHC) class I and II antigen presentation pathways in primary DCs. HBsAgS VLPs impaired plasmacytoid DC (pDC) interferon alpha (IFNα) production in response to CpG in vitro, but did not alter conventional DC (cDC) or pDC phenotype when administered in vivo. To assess cellular immune responses, HBsAgS VLPs were generated containing the ovalbumin (OVA) model epitopes OVA(257-264) and OVA(323-339) to access MHCI and MHCII antigen presentation pathways, respectively; both in vitro and following immunisation in vivo. HBsAgS VLP-OVA(257-264) elicited CTL responses in vivo that were not enhanced by inclusion of an additional MHCII helper epitope. HBsAgS VLP-OVA(257-264) administered in vivo was cross-presented by CD8(+) DCs, but not CD8(-) DCs. Therefore, HBsAgS VLPs can deliver antigen to both MHCI and MHCII antigen presentation pathways in primary DCs and promote cytotoxic and helper T cell priming despite their suppressive effect on pDCs. PMID:23473776

  16. Luciferase mRNA Transfection of Antigen Presenting Cells Permits Sensitive Nonradioactive Measurement of Cellular and Humoral Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Tana A. Omokoko

    2016-01-01

    Full Text Available Immunotherapy is rapidly evolving as an effective treatment option for many cancers. With the emerging fields of cancer vaccines and adoptive cell transfer therapies, there is an increasing demand for high-throughput in vitro cytotoxicity assays that efficiently analyze immune effector functions. The gold standard 51Cr-release assay is very accurate but has the major disadvantage of being radioactive. We reveal the development of a versatile and nonradioactive firefly luciferase in vitro transcribed (IVT RNA-based assay. Demonstrating high efficiency, consistency, and excellent target cell viability, our optimized luciferase IVT RNA is used to transfect dividing and nondividing primary antigen presenting cells. Together with the long-lasting expression and minimal background, the direct measurement of intracellular luciferase activity of living cells allows for the monitoring of killing kinetics and displays paramount sensitivity. The ability to cotransfect the IVT RNA of the luciferase reporter and the antigen of interest into the antigen presenting cells and its simple read-out procedure render the assay high-throughput in nature. Results generated were comparable to the 51Cr release and further confirmed the assay’s ability to measure antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. The assay’s combined simplicity, practicality, and efficiency tailor it for the analysis of antigen-specific cellular and humoral effector functions during the development of novel immunotherapies.

  17. Hsp70 enhances presentation of FMDV antigen to bovine CD4+ T cells in vitro

    OpenAIRE

    McLaughlin, Kerry; Seago, Julian; Robinson, Lucy; Kelly, Charles; Charleston, Bryan

    2010-01-01

    International audience Foot-and-mouth disease virus (FMDV) is the causative agent of a highly contagious acute vesicular disease affecting cloven-hoofed animals, including cattle, sheep and pigs. The current vaccine induces a rapid humoral response, but the duration of the protective antibody response is variable, possibly associated with a variable specific CD4+ T cell response. We investigated the use of heat shock protein 70 (Hsp70) as a molecular chaperone to target viral antigen to th...

  18. Target antigen expression on a professional antigen-presenting cell induces superior proliferative antitumor T-cell responses via chimeric T-cell receptors.

    Science.gov (United States)

    Rossig, Claudia; Bär, Annette; Pscherer, Sibylle; Altvater, Bianca; Pule, Martin; Rooney, Cliona M; Brenner, Malcolm K; Jürgens, Heribert; Vormoor, Josef

    2006-01-01

    Human T cells expressing tumor antigen-specific chimeric receptors fail to sustain their growth and activation in vivo, which greatly reduces their therapeutic value. The defective proliferative response to tumor cells in vitro can partly be overcome by concomitant CD28 costimulatory signaling. We investigated whether T-cell activation via chimeric receptors (chRec) can be further improved by ligand expression on antigen-presenting cells of B-cell origin. We generated Epstein-Barr virus (EBV)-specific cytotoxic T lymphocytes (CTLs) expressing a CD19-specific chRec. These CTLs are provided with native receptor stimulation by autologous EBV-transformed B-lymphoblastoid cell lines (LCLs) but exclusively with chRec (CD19-specific) stimulation by allogeneic, human leukocyte antigen (HLA)-mismatched CD19+ LCLs. CD19zeta-transduced EBV-specific CTLs specifically lysed both allogeneic EBV targets and CD19+ tumor cells through the chRec in a major histocompatibility complex-independent manner, while maintaining their ability to recognize autologous EBV targets through the native T-cell receptor. The transduced CTLs failed to proliferate in response to CD19+ tumor targets even in the presence of CD28 costimulatory signaling. By contrast, CD19 expressed on HLA-mismatched LCL-induced T-cell activation and long-term proliferation that essentially duplicated the result from native receptor stimulation with autologous LCLs, suggesting that a deficit of costimulatory molecules on target cells in addition to CD28 is indeed responsible for inadequate chRec-mediated T-cell function. Hence, effective tumor immunotherapy may be favored if engagement of the chRec on modified T cells is complemented by interaction with multiple costimulator molecules. The use of T cells with native specificity for EBV may be one means of attaining this objective. PMID:16365597

  19. Cytokine profiles and phenotype regulation of antigen presenting cells by genotype-I porcine reproductive and respiratory syndrome virus isolates

    OpenAIRE

    Gimeno Mariona; Darwich Laila; Diaz Ivan; de la Torre Eugenia; Pujols Joan; Martín Marga; Inumaru Shigeki; Cano Esmeralda; Domingo Mariano; Montoya Maria; Mateu Enric

    2011-01-01

    Abstract The present study examined the immunological response of antigen presenting cells (APC) to genotype-I isolates of porcine reproductive and respiratory syndrome virus (PRRSV) infection by analysing the cytokine profile induced and evaluating the changes taking place upon infection on immunologically relevant cell markers (MHCI, MHCII, CD80/86, CD14, CD16, CD163, CD172a, SWC9). Several types of APC were infected with 39 PRRSV isolates. The results show that different isolates were able...

  20. Dendritic cells cross-present HIV antigens from live as well as apoptotic infected CD4+ T lymphocytes

    OpenAIRE

    Marañón, Concepción; Desoutter, Jean-François; Hoeffel, Guillaume; Cohen, William; Hanau, Daniel; Hosmalin, Anne

    2004-01-01

    A better understanding of the antigen presentation pathways that lead to CD8+ T cell recognition of HIV epitopes in vivo is needed to achieve better immune control of HIV replication. Here, we show that cross-presentation of very small amounts of HIV proteins from apoptotic infected CD4+ T lymphocytes by dendritic cells to CD8+ T cells is much more efficient than other known HIV presentation pathways, i.e., direct presentation of infectious virus or cross-presentation of defective virus. Unex...

  1. 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...

  2. A novel system of artificial antigen-presenting cells efficiently stimulates Flu peptide-specific cytotoxic T cells in vitro

    International Nuclear Information System (INIS)

    Highlights: → Adoptive immunotherapy depends on relevant numbers of cytolytic T lymphocytes. → An ideal artificial APCs system was successfully prepared in vivo. → Controlled release of IL-2 leads to much more T-cell expansion. → This system is better than general cellular APCs on T-cell expansion. -- Abstract: Therapeutic numbers of antigen-specific cytotoxic T lymphocytes (CTLs) are key effectors in successful adoptive immunotherapy. However, efficient and reproducible methods to meet the qualification remain poor. To address this issue, we designed the artificial antigen-presenting cell (aAPC) system based on poly(lactic-co-glycolic acid) (PLGA). A modified emulsion method was used for the preparation of PLGA particles encapsulating interleukin-2 (IL-2). Biotinylated molecular ligands for recognition and co-stimulation of T cells were attached to the particle surface through the binding of avidin-biotin. These formed the aAPC system. The function of aAPCs in the proliferation of specific CTLs against human Flu antigen was detected by enzyme-linked immunospot assay (ELISPOT) and MTT staining methods. Finally, we successfully prepared this suitable aAPC system. The results show that IL-2 is released from aAPCs in a sustained manner over 30 days. This dramatically improves the stimulatory capacity of this system as compared to the effect of exogenous addition of cytokine. In addition, our aAPCs promote the proliferation of Flu antigen-specific CTLs more effectively than the autologous cellular APCs. Here, this aAPC platform is proved to be suitable for expansion of human antigen-specific T cells.

  3. A novel system of artificial antigen-presenting cells efficiently stimulates Flu peptide-specific cytotoxic T cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hui [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China); Peng, Ji-Run, E-mail: pengjr@medmail.com.cn [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China); Chen, Peng-Cheng; Gong, Lei [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China); Qiao, Shi-Shi [Department of Hepatobiliary Surgery, The First Affiliated Hospital, Zhengzhou University, Zhengzhou 450052 (China); Wang, Wen-Zhen; Cui, Zhu-Qingqing; Yu, Xin; Wei, Yu-Hua [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China); Leng, Xi-Sheng, E-mail: lengxs2003@yahoo.com.cn [Department of Hepatobiliary Surgery, Peking University People' s Hospital, Beijing 100044 (China)

    2011-08-05

    Highlights: {yields} Adoptive immunotherapy depends on relevant numbers of cytolytic T lymphocytes. {yields} An ideal artificial APCs system was successfully prepared in vivo. {yields} Controlled release of IL-2 leads to much more T-cell expansion. {yields} This system is better than general cellular APCs on T-cell expansion. -- Abstract: Therapeutic numbers of antigen-specific cytotoxic T lymphocytes (CTLs) are key effectors in successful adoptive immunotherapy. However, efficient and reproducible methods to meet the qualification remain poor. To address this issue, we designed the artificial antigen-presenting cell (aAPC) system based on poly(lactic-co-glycolic acid) (PLGA). A modified emulsion method was used for the preparation of PLGA particles encapsulating interleukin-2 (IL-2). Biotinylated molecular ligands for recognition and co-stimulation of T cells were attached to the particle surface through the binding of avidin-biotin. These formed the aAPC system. The function of aAPCs in the proliferation of specific CTLs against human Flu antigen was detected by enzyme-linked immunospot assay (ELISPOT) and MTT staining methods. Finally, we successfully prepared this suitable aAPC system. The results show that IL-2 is released from aAPCs in a sustained manner over 30 days. This dramatically improves the stimulatory capacity of this system as compared to the effect of exogenous addition of cytokine. In addition, our aAPCs promote the proliferation of Flu antigen-specific CTLs more effectively than the autologous cellular APCs. Here, this aAPC platform is proved to be suitable for expansion of human antigen-specific T cells.

  4. Self-Antigen Presentation by Keratinocytes in the Inflamed Adult Skin Modulates T-Cell Auto-Reactivity.

    Science.gov (United States)

    Meister, Michael; Tounsi, Amel; Gaffal, Evelyn; Bald, Tobias; Papatriantafyllou, Maria; Ludwig, Julia; Pougialis, Georg; Bestvater, Felix; Klotz, Luisa; Moldenhauer, Gerhard; Tüting, Thomas; Hämmerling, Günter J; Arnold, Bernd; Oelert, Thilo

    2015-08-01

    Keratinocytes have a pivotal role in the regulation of immune responses, but the impact of antigen presentation by these cells is still poorly understood, particularly in a situation where the antigen will be presented only in adult life. Here, we generated a transgenic mouse model in which keratinocytes exclusively present a myelin basic protein (MBP) peptide covalently linked to the major histocompatibility complex class II β-chain, solely under inflammatory conditions. In these mice, inflammation caused by epicutaneous contact sensitizer treatment resulted in keratinocyte-mediated expansion of MBP-specific CD4(+) T cells in the skin. Moreover, repeated contact sensitizer application preceding a systemic MBP immunization reduced the reactivity of the respective CD4(+) T cells and lowered the symptoms of the resulting experimental autoimmune encephalomyelitis. This downregulation was CD4(+) T-cell-mediated and dependent on the presence of the immune modulator Dickkopf-3. Thus, presentation of a neo self-antigen by keratinocytes in the inflamed, adult skin can modulate CD4(+) T-cell auto-aggression at a distal organ. PMID:25835957

  5. Comparison of microglia and infiltrating CD11c+ cells as antigen presenting cells for T cell proliferation and cytokine response

    DEFF Research Database (Denmark)

    Wlodarczyk, Agnieszka; Løbner, Morten; Cédile, Oriane;

    2014-01-01

    BACKGROUND: Tissue-resident antigen-presenting cells (APC) exert a major influence on the local immune environment. Microglia are resident myeloid cells in the central nervous system (CNS), deriving from early post-embryonic precursors, distinct from adult hematopoietic lineages. Dendritic cells...... (DC) and macrophages infiltrate the CNS during experimental autoimmune encephalomyelitis (EAE). Microglia are not considered to be as effective APC as DC or macrophages. METHODS: In this work we compared the antigen presenting capacity of CD11c+ and CD11c- microglia subsets with infiltrating CD11c......+ APC, which include DC. The microglial subpopulations (CD11c- CD45dim CD11b+ and CD11c+ CD45dim CD11b+) as well as infiltrating CD11c+ CD45high cells were sorted from CNS of C57BL/6 mice with EAE. Sorted cells were characterised by flow cytometry for surface phenotype and by quantitative real-time PCR...

  6. Aromatic-dependent salmonella as anti-bacterial vaccines and as presenters of heterologous antigens or of DNA encoding them.

    Science.gov (United States)

    Stocker, B A

    2000-09-29

    The development of live bacterial vaccines is reviewed, in particular aromatic-dependent Salmonella, either for protection against the corresponding infections (including typhoid fever) or as carrier-presenter of antigens of unrelated pathogens or of DNA specifying them. Aromatic-dependent Salmonella live vaccines are also compared with BCG and Ty21a and the recent records of exceptional situations are discussed in which aroA (deletion) strains of Salmonella typhimurium cause progressive disease in mice. PMID:11000459

  7. Interleukin-15-induced CD56(+) myeloid dendritic cells combine potent tumor antigen presentation with direct tumoricidal potential.

    Science.gov (United States)

    Anguille, Sébastien; Lion, Eva; Tel, Jurjen; de Vries, I Jolanda M; Couderé, Karen; Fromm, Phillip D; Van Tendeloo, Viggo F; Smits, Evelien L; Berneman, Zwi N

    2012-01-01

    Dendritic cells (DCs) are the quintessential antigen-presenting cells of the human immune system and play a prime role in coordinating innate and adaptive immune responses, explaining the strong and still growing interest in their application for cancer immunotherapy. Much current research in the field of DC-based immunotherapy focuses on optimizing the culture conditions for in vitro DC generation in order to assure that DCs with the best possible immunogenic qualities are being used for immunotherapy. In this context, monocyte-derived DCs that are alternatively induced by interleukin-15 (IL-15 DCs) have attracted recent attention due to their superior immunostimulatory characteristics. In this study, we show that IL-15 DCs, in addition to potent tumor antigen-presenting function, possess tumoricidal potential and thus qualify for the designation of killer DCs. Notwithstanding marked expression of the natural killer (NK) cell marker CD56 on a subset of IL-15 DCs, we found no evidence of a further phenotypic overlap between IL-15 DCs and NK cells. Allostimulation and antigen presentation assays confirmed that IL-15 DCs should be regarded as bona fide myeloid DCs not only from the phenotypic but also from the functional point of view. Concerning their cytotoxic activity, we demonstrate that IL-15 DCs are able to induce apoptotic cell death of the human K562 tumor cell line, while sparing tumor antigen-specific T cells. The cytotoxicity of IL-15 DCs is predominantly mediated by granzyme B and, to a small extent, by tumor necrosis factor-α (TNF-α)-related apoptosis-inducing ligand (TRAIL) but is independent of perforin, Fas ligand and TNF-α. In conclusion, our data provide evidence of a previously unappreciated role for IL-15 in the differentiation of human monocytes towards killer DCs. The observation that IL-15 DCs have killer DC capacity lends further support to their implementation in DC-based immunotherapy protocols. PMID:23284789

  8. Presentation of antigen by B cells subsets. Pt. 1. Lyb-5+ and Lyb-5- B cells differ in ability to stimulate specific T cells

    International Nuclear Information System (INIS)

    We have examined the antigen presenting cell (APC) function of different B cells. Resident, peritoneal B cells from normal mice were more efficient than splenic B cells in presenting antigen to CD4+ T cell lines. Peritoneal B cells from X-linked immunodeficient (Xid) mice, by contrast, stimulated no detectable responses. Xid splenic B cells were much less efficient APC than normal splenic B cells. B cells from neonatal mice also were very poor APC until the mice were 3 to 4 weeks old. Xid B cells presented antigen to T cell hybridomas as well as normal B cells showing that they process antigen normally. Thus, the defect is most likely in providing secondary signals. The ability of B cells to present antigen efficiency correlates with the percentage of B cells reported to express the Lyb-5 antigen. Anti-Lyb-5 serum and complement abrogated the APC activity of B cells suggesting that Lyb-5+, but not Lyb-5- cells are efficient APC. We also found that activated and resting normal splenic B cells, separated by buoyant density, presented antigen equally. Both populations also contained Lyb-5+ B cells although they were a larger fraction of the activated cells. Lyb-5 is now thought to be an activation antigen rather than a differentiation antigen. If this idea is correct, then our data indicate that anti-Lyb-5 more cleanly separates activated and resting B cells than buoyant density techniques. (author). 38 refs, 7 figs, 1 tab

  9. Emerging roles for antigen presentation in establishing host-microbiome symbiosis.

    Science.gov (United States)

    Bessman, Nicholas J; Sonnenberg, Gregory F

    2016-07-01

    Trillions of beneficial bacteria inhabit the intestinal tract of healthy mammals from birth. Accordingly, mammalian hosts have evolved a series of complementary and redundant pathways to limit pathologic immune responses against these bacteria, while simultaneously protecting against enteric pathogen invasion. These pathways can be generically responsive to the presence of any commensal bacteria and innate in nature, as for IL-22-related pathways. Alternatively, specific bacterial antigens can drive a distinct set of adaptive immune cell responses, including IgA affinity maturation and secretion, and a recently described pathway of intestinal selection whereby MHCII(+) ILC3 deletes commensal bacteria-reactive CD4 T cells. These pathways can either promote or inhibit colonization by specific subsets of commensal bacteria, and cooperatively maintain intestinal homeostasis. In this review, we will highlight recent developments in understanding how these diverse pathways complement each other to cooperatively shape the symbiotic relationship between commensal bacteria and mammalian hosts. PMID:27319348

  10. NLRC5 elicits antitumor immunity by enhancing processing and presentation of tumor antigens to CD8(+) T lymphocytes.

    Science.gov (United States)

    Rodriguez, Galaxia M; Bobbala, Diwakar; Serrano, Daniel; Mayhue, Marian; Champagne, Audrey; Saucier, Caroline; Steimle, Viktor; Kufer, Thomas A; Menendez, Alfredo; Ramanathan, Sheela; Ilangumaran, Subburaj

    2016-06-01

    Cancers can escape immunesurveillance by diminishing the expression of MHC class-I molecules (MHC-I) and components of the antigen-processing machinery (APM). Developing new approaches to reverse these defects could boost the efforts to restore antitumor immunity. Recent studies have shown that the expression of MHC-I and antigen-processing molecules is transcriptionally regulated by NOD-like receptor CARD domain containing 5 (NLRC5). To investigate whether NLRC5 could be used to improve tumor immunogenicity, we established stable lines of B16-F10 melanoma cells expressing NLRC5 (B16-5), the T cell co-stimulatory molecule CD80 (B16-CD80) or both (B16-5/80). Cells harboring NLRC5 constitutively expressed MHC-I and LMP2, LMP7 and TAP1 genes of the APM. The B16-5 cells efficiently presented the melanoma antigenic peptide gp10025-33 to Pmel-1 TCR transgenic CD8(+) T cells and induced their proliferation. In the presence of CD80, B16-5 cells stimulated Pmel-1 cells even without the addition of gp100 peptide, indicating that NLRC5 facilitated the processing and presentation of endogenous tumor antigen. Upon subcutaneous implantation, B16-5 cells showed markedly reduced tumor growth in C57BL/6 hosts but not in immunodeficient hosts, indicating that the NLRC5-expressing tumor cells elicited antitumor immunity. Following intravenous injection, B16-5 and B16-5/80 cells formed fewer lung tumor foci compared to control cells. In mice depleted of CD8(+) T cells, B16-5 cells formed large subcutaneous and lung tumors. Finally, immunization with irradiated B16-5 cells conferred protection against challenge by parental B16 cells. Collectively, our findings indicate that NLRC5 could be exploited to restore tumor immunogenicity and to stimulate protective antitumor immunity. PMID:27471621

  11. Prolonged antigen presentation by immune complex-binding dendritic cells programs the proliferative capacity of memory CD8 T cells.

    Science.gov (United States)

    León, Beatriz; Ballesteros-Tato, André; Randall, Troy D; Lund, Frances E

    2014-07-28

    The commitment of naive CD8 T cells to effector or memory cell fates can occur after a single day of antigenic stimulation even though virus-derived antigens (Ags) are still presented by DCs long after acute infection is resolved. However, the effects of extended Ag presentation on CD8 T cells are undefined and the mechanisms that regulate prolonged Ag presentation are unknown. We showed that the sustained presentation of two different epitopes from influenza virus by DCs prevented the premature contraction of the primary virus-specific CD8 T cell response. Although prolonged Ag presentation did not alter the number of memory CD8 T cells that developed, it was essential for programming the capacity of these cells to proliferate, produce cytokines, and protect the host after secondary challenge. Importantly, prolonged Ag presentation by DCs was dependent on virus-specific, isotype-switched antibodies (Abs) that facilitated the capture and cross-presentation of viral Ags by FcγR-expressing DCs. Collectively, our results demonstrate that B cells and Abs can regulate the quality and functionality of a subset of antiviral CD8 T cell memory responses and do so by promoting sustained Ag presentation by DCs during the contraction phase of the primary T cell response. PMID:25002751

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

    Science.gov (United States)

    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

  13. Increased generation of Foxp3(+) regulatory T cells by manipulating antigen presentation in the thymus.

    Science.gov (United States)

    Lin, Jiqiang; Yang, Lu; Silva, Hernandez Moura; Trzeciak, Alissa; Choi, Yongwon; Schwab, Susan R; Dustin, Michael L; Lafaille, Juan J

    2016-01-01

    Regulatory T-cell (Treg) selection in the thymus is essential to prevent autoimmune diseases. Although important rules for Treg selection have been established, there is controversy regarding the degree of self-reactivity displayed by T-cell receptors expressed by Treg cells. In this study we have developed a model of autoimmune skin inflammation, to determine key parameters in the generation of skin-reactive Treg cells in the thymus (tTreg). tTreg development is predominantly AIRE dependent, with an AIRE-independent component. Without the knowledge of antigen recognized by skin-reactive Treg cells, we are able to enhance skin-specific tTreg cell generation using three approaches. First, we increase medullary thymic epithelial cells by using mice lacking osteoprotegerin or by adding TRANCE (RANKL, Tnfsf11). Second, we inject intrathymically peripheral dendritic cells from skin-draining sites. Finally, we inject skin tissue lysates intrathymically. These findings have implications for enhancing the generation of organ-specific Treg cells in autoimmune diseases. PMID:26923114

  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. Loss of proliferation and antigen presentation activity following internalization of polydispersed carbon nanotubes by primary lung epithelial cells.

    Directory of Open Access Journals (Sweden)

    Mandavi Kumari

    Full Text Available Interactions between poly-dispersed acid functionalized single walled carbon nanotubes (AF-SWCNTs and primary lung epithelial (PLE cells were studied. Peritoneal macrophages (PMs, known phagocytic cells were used as positive controls in this study. Recovery of live cells from cultures of PLE cells and PMs was significantly reduced in the presence of AF-SWCNTs, in a time and dose dependent manner. Both PLE cells as well as PMs could take up fluorescence tagged AF-SWCNTs in a time dependent manner and this uptake was significantly blocked by cytochalasin D, an agent that blocks the activity of acto-myosin fibers and therefore the phagocytic activity of cells. Confocal microscopic studies confirmed that AF-SWCNTs were internalized by both PLE cells and PMs. Intra-trachially instilled AF-SWCNTs could also be taken up by lung epithelial cells as well as alveolar macrophages. Freshly isolated PLE cells had significant cell division activity and cell cycling studies indicated that treatment with AF-SWCNTs resulted in a marked reduction in S-phase of the cell cycle. In a previously standardized system to study BCG antigen presentation by PLE cells and PMs to sensitized T helper cells, AF-SWCNTs could significantly lower the antigen presentation ability of both cell types. These results show that mouse primary lung epithelial cells can efficiently internalize AF-SWCNTs and the uptake of nanotubes interfered with biological functions of PLE cells including their ability to present BCG antigens to sensitized T helper cells.

  16. CD4+ T cell-mediated presentation of non-infectious HIV-1virion antigens to HIV-specific CD8+ T cells

    Institute of Scientific and Technical Information of China (English)

    XU Jian-qing; Franco Lori; Julianna Lisziewicz

    2006-01-01

    Background The mechanism of chronic immune activation and impairment of HIV-specific immune responses during chronic infection is not fully understood. However, it is known that high immune activation leads to more rapid progression to AIDS. We hypothesize that CD4+ T cell-mediated viral antigen presentation contributes to this pathologic immune activation in HIV-infected individuals.Methods HIV-specific T cells, responding to noninfectious HIV-1 virions as antigen, were measured by flow cytometric assays. These experimental conditions reflect the in vivo condition where noninfectious HIV-1 represents more than 99% of the antigens.Results CD4+ T cells purified from HIV-infected individuals were capable of cross presenting exogenous noninfectious HIV-1 virions to HIV-1-specific CD8+ T cells. Cross presentation required the entry of HIV-1 to CD4+ T cells and antigen translocation from endoplasmic reticulum to the Golgi complex. Blocking CD4+mediated activation of HIV-specific CD8+ T cells and redirecting the viral antigens to antigen presenting cells improved HIV-specific T cell responses.Conclusions One possible cause of chronic immune activation and impairment of HIV-1 specific T cell responses is represented by HIV-1 harboring CD4+ T cells cross presenting HIV-1 antigen to activate CD8+ T cells. This new mechanism provides the first evidence that cross presentation of noninfectious HIV-1. Virions play a role in the immunopathogenesis of HIV-1 infection.

  17. Corruption of dendritic cell antigen presentation during acute GVHD leads to regulatory T-cell failure and chronic GVHD.

    Science.gov (United States)

    Leveque-El Mouttie, Lucie; Koyama, Motoko; Le Texier, Laetitia; Markey, Kate A; Cheong, Melody; Kuns, Rachel D; Lineburg, Katie E; Teal, Bianca E; Alexander, Kylie A; Clouston, Andrew D; Blazar, Bruce R; Hill, Geoffrey R; MacDonald, Kelli P A

    2016-08-11

    Chronic graft-versus-host disease (cGVHD) is a major cause of late mortality following allogeneic bone marrow transplantation (BMT) and is characterized by tissue fibrosis manifesting as scleroderma and bronchiolitis obliterans. The development of acute GVHD (aGVHD) is a powerful clinical predictor of subsequent cGVHD, suggesting that aGVHD may invoke the immunologic pathways responsible for cGVHD. In preclinical models in which sclerodermatous cGVHD develops after a preceding period of mild aGVHD, we show that antigen presentation within major histocompatibility complex (MHC) class II of donor dendritic cells (DCs) is markedly impaired early after BMT. This is associated with a failure of regulatory T-cell (Treg) homeostasis and cGVHD. Donor DC-restricted deletion of MHC class II phenocopied this Treg deficiency and cGVHD. Moreover, specific depletion of donor Tregs after BMT also induced cGVHD, whereas adoptive transfer of Tregs ameliorated it. These data demonstrate that the defect in Treg homeostasis seen in cGVHD is a causative lesion and is downstream of defective antigen presentation within MHC class II that is induced by aGVHD. PMID:27338097

  18. Beta2-Adrenoreceptor agonist inhibits antigen cross-presentation by dendritic cells

    OpenAIRE

    Hervé, Julie; Dubreil, Laurence; Tardif, Virginie; Terme, Mickaël; Pogu, Sylvie; Anegon, Ignacio; Rozec, Bertrand; Gauthier, Chantal; Bach, Jean-Marie; Blancou, Philippe

    2013-01-01

    Despite widespread usage of β-adrenergic receptor (AR) agonists and antagonists in current clinical practice, our understanding of their interactions with the immune system is surprisingly sparse. Among the AR expressed by dendritic cells (DC), β2-AR can modify in vitro cytokine release upon stimulation. Because DC play a pivotal role in CD8(+) T cell immune responses, we examined the effects of β2-AR stimulation on MHC class I exogenous peptide presentation and cross-presentation capacities....

  19. Endoplasmic reticulum targeting alters regulation of expression and antigen presentation of proinsulin.

    Science.gov (United States)

    Hsu, Hsiang-Ting; Janßen, Linda; Lawand, Myriam; Kim, Jessica; Perez-Arroyo, Alicia; Culina, Slobodan; Gdoura, Abdel; Burgevin, Anne; Cumenal, Delphine; Fourneau, Yousra; Moser, Anna; Kratzer, Roland; Wong, F Susan; Springer, Sebastian; van Endert, Peter

    2014-06-01

    Peptide ligands presented by MHC class I (MHC-I) molecules are produced by degradation of cytosolic and nuclear, but also endoplasmic reticulum (ER)-resident, proteins by the proteasome. However, Ag processing of ER proteins remains little characterized. Studying processing and presentation of proinsulin, which plays a pivotal role in autoimmune diabetes, we found that targeting to the ER has profound effects not only on how proinsulin is degraded, but also on regulation of its cellular levels. While proteasome inhibition inhibited degradation and presentation of cytosolic proinsulin, as expected, it reduced the abundance of ER-targeted proinsulin. This targeting and protein modifications modifying protein half-life also had profound effects on MHC-I presentation and proteolytic processing of proinsulin. Thus, presentation of stable luminal forms was inefficient but enhanced by proteasome inhibition, whereas that of unstable luminal forms and of a cytosolic form were more efficient and compromised by proteasome inhibitors. Distinct stability of peptide MHC complexes produced from cytosolic and luminal proinsulin suggests that different proteolytic activities process the two Ag forms. Thus, both structural features and subcellular targeting of Ags can have strong effects on the processing pathways engaged by MHC-I-restricted Ags, and on the efficiency and regulation of their presentation. PMID:24778449

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

    Science.gov (United States)

    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

  1. B lymphocytes as natural antigen-presenting cells (APC) of their own Ig receptor determinants

    International Nuclear Information System (INIS)

    The authors use Igk-lb allotype-specific rat T cell proliferation(Pr) in vitro as a model of natural Ig determinants B cell presentation in Ig-specific T-B cell interactions. As shown before Igk-lb-specific responsiveness of AUG(RT-l/sup c/, Igk-la) and WAG (RT-l, Igk-la) rats is controlled by dominant Ir gene, linked to RT-l/sup c/. Only IgG(Igk-lb)-pulsed splenic APC of AUG(responder) but not WAG(non-responder) origin induce specific F1 (WAGxAUG) T cell Pr. The same restriction was observed if purified B cells from Igk-l congeneic AUG-lb and WAG-lb rats were used as APC. B cell presentation was found to be sensitive to high irradiation dose(2000 rad). Anti-RT-l monoclonal antibody inhibition studies suggested RT-lB(I-A) molecule as a main restricting element of Igk-lb T cell recognition. B cell and splenic APC presentation of Igk-lb allotype was not inhibited by poly- and monoclonal anti-Igk-lb antibodies. Allelic exclusion of Igk-lb presentation by B cells from heterozygous F1 (WAG-lbx AUG) rats was demonstrated by panning with antiallotypic reagents. Important, that irradiated anti-Igk-lb T cells induce specific Pr of normal Igk-lb-positive B cells. The data demonstrate MHC-restricted B cell presentation of their own receptor determinants, distinct from serologically-defined epitopes. T cell recognition of these determinants induce specific Pr of Ig-recognizing T cells and Ig-presenting B lymphocytes

  2. Cytokine profiles and phenotype regulation of antigen presenting cells by genotype-I porcine reproductive and respiratory syndrome virus isolates.

    Science.gov (United States)

    Gimeno, Mariona; Darwich, Laila; Diaz, Ivan; de la Torre, Eugenia; Pujols, Joan; Martín, Marga; Inumaru, Shigeki; Cano, Esmeralda; Domingo, Mariano; Montoya, Maria; Mateu, Enric

    2011-01-01

    The present study examined the immunological response of antigen presenting cells (APC) to genotype-I isolates of porcine reproductive and respiratory syndrome virus (PRRSV) infection by analysing the cytokine profile induced and evaluating the changes taking place upon infection on immunologically relevant cell markers (MHCI, MHCII, CD80/86, CD14, CD16, CD163, CD172a, SWC9). Several types of APC were infected with 39 PRRSV isolates. The results show that different isolates were able to induce different patterns of IL-10 and TNF-α. The four possible phenotypes based on the ability to induce IL-10 and/or TNF-α were observed, although different cell types seemed to have different capabilities. In addition, isolates inducing different cytokine-release profiles on APC could induce different expression of cell markers. PMID:21314968

  3. Cytokine profiles and phenotype regulation of antigen presenting cells by genotype-I porcine reproductive and respiratory syndrome virus isolates

    Directory of Open Access Journals (Sweden)

    Gimeno Mariona

    2011-01-01

    Full Text Available Abstract The present study examined the immunological response of antigen presenting cells (APC to genotype-I isolates of porcine reproductive and respiratory syndrome virus (PRRSV infection by analysing the cytokine profile induced and evaluating the changes taking place upon infection on immunologically relevant cell markers (MHCI, MHCII, CD80/86, CD14, CD16, CD163, CD172a, SWC9. Several types of APC were infected with 39 PRRSV isolates. The results show that different isolates were able to induce different patterns of IL-10 and TNF-α. The four possible phenotypes based on the ability to induce IL-10 and/or TNF-α were observed, although different cell types seemed to have different capabilities. In addition, isolates inducing different cytokine-release profiles on APC could induce different expression of cell markers.

  4. Cross-presentation of tumour antigens by human induced pluripotent stem cell-derived CD141(+)XCR1+ dendritic cells.

    Science.gov (United States)

    Silk, K M; Silk, J D; Ichiryu, N; Davies, T J; Nolan, K F; Leishman, A J; Carpenter, L; Watt, S M; Cerundolo, V; Fairchild, P J

    2012-10-01

    Monocyte-derived dendritic cells (moDC) have been widely used in cancer immunotherapy but show significant donor-to-donor variability and low capacity for the cross-presentation of tumour-associated antigens (TAA) to CD8(+) T cells, greatly limiting the success of this approach. Given recent developments in induced pluripotency and the relative ease with which induced pluripotent stem (iPS) cell lines may be generated from individuals, we have succeeded in differentiating dendritic cells (DC) from human leukocyte antigen (HLA)-A(*)0201(+) iPS cells (iPS cell-derived DC (ipDC)), using protocols compliant with their subsequent clinical application. Unlike moDC, a subset of ipDC was found to coexpress CD141 and XCR1 that have been shown previously to define the human equivalent of mouse CD8α(+) DC, in which the capacity for cross-presentation has been shown to reside. Accordingly, ipDC were able to cross-present the TAA, Melan A, to a CD8(+) T-cell clone and stimulate primary Melan A-specific responses among naïve T cells from an HLA-A(*)0201(+) donor. Given that CD141(+)XCR1(+) DC are present in peripheral blood in trace numbers that preclude their clinical application, the ability to generate a potentially unlimited source from iPS cells offers the possibility of harnessing their capacity for cross-priming of cytotoxic T lymphocytes for the induction of tumour-specific immune responses. PMID:22071967

  5. Enhanced immune stimulation by a therapeutic lymphoma tumor antigen vaccine produced in insect cells involves mannose receptor targeting to antigen presenting cells.

    Science.gov (United States)

    Betting, David J; Mu, Xi Y; Kafi, Kamran; McDonnel, Desmond; Rosas, Francisco; Gold, Daniel P; Timmerman, John M

    2009-01-01

    Therapeutic vaccination of lymphoma patients with tumor-specific immunoglobulin (idiotype, Id) coupled to the carrier protein keyhole limpet hemocyanin (Id-KLH) is undergoing clinical investigation, and methods to improve the immunogenicity of these and other protein tumor antigen vaccines are being sought. Id proteins can be produced via tumor-myeloma hybridomas or recombinant methods in mammalian, bacteria, or insect cells. We now demonstrate that terminal mannose residues, characteristic of recombinant proteins produced in insect cells, yield Id proteins with significantly enhanced immunostimulatory properties compared to Id proteins derived from mammalian cells. Recombinant baculovirus-infected insect cell-derived Id showed higher binding to and activation of human dendritic cells mediated by mannose receptors. In vivo, insect cell-derived Id elicited higher levels of tumor-specific CD8+ cytotoxic T lymphocyte (CTL) and improved eradication of pre-established murine lymphoma. Insect cell and mammalian Id generated similar levels of tumor-specific antibodies, showing no impairment in antibody responses to native tumor antigen despite the glycoslylation differences in the immunogen. Combining insect cell production and maleimide-based KLH conjugation offered the highest levels of anti-tumor immunity. Our data comparing sources of recombinant Id protein tumor antigens used in therapeutic cancer vaccines demonstrate that insect cell-derived antigens can offer several immunologic advantages over proteins derived from mammalian sources. PMID:19000731

  6. Antigen presenting cells in the skin of a patient with hair loss and systemic lupus erythematosus

    OpenAIRE

    Ana Maria Abreu Velez; Julia G Girard; Michael S. Howard,

    2009-01-01

    Context: Hair loss is one of the most striking clinical features of active systemic lupus erythematosus (SLE), however, very few studies have investigated the immunological features of this process. Case report: We describe a 33 years old female who presented with scalp hair loss and arthralgias. Physical examination revealed erythematous plaques on the nose and scalp, with bitemporal hair loss. Scalp biopsies revealed epidermal hyperkeratosis, with a mild interface infiltrate of lymphocytes ...

  7. Class-switched anti-insulin antibodies originate from unconventional antigen presentation in multiple lymphoid sites.

    Science.gov (United States)

    Wan, Xiaoxiao; Thomas, James W; Unanue, Emil R

    2016-05-30

    Autoantibodies to insulin are a harbinger of autoimmunity in type 1 diabetes in humans and in non-obese diabetic mice. To understand the genesis of these autoantibodies, we investigated the interactions of insulin-specific T and B lymphocytes using T cell and B cell receptor transgenic mice. We found spontaneous anti-insulin germinal center (GC) formation throughout lymphoid tissues with GC B cells binding insulin. Moreover, because of the nature of the insulin epitope recognized by the T cells, it was evident that GC B cells presented a broader repertoire of insulin epitopes. Such broader recognition was reproduced by activating naive B cells ex vivo with a combination of CD40 ligand and interleukin 4. Thus, insulin immunoreactivity extends beyond the pancreatic lymph node-islets of Langerhans axis and indicates that circulating insulin, despite its very low levels, can have an influence on diabetogenesis. PMID:27139492

  8. Human sunlight-induced basal-cell-carcinoma-associated dendritic cells are deficient in T cell co-stimulatory molecules and are impaired as antigen-presenting cells.

    OpenAIRE

    Nestle, F.O.; Burg, G.; Fäh, J; Wrone-Smith, T; Nickoloff, B. J.

    1997-01-01

    Immune surveillance of skin cancer involves the stimulation of effector T cells by tumor-derived antigens and antigen-presenting cells (APCs). An effective APC must not only display processed antigen in the context of MHC molecules but also express co-stimulatory molecules that are required to fully activate T cells. One of the most common cutaneous neoplasms is basal cell carcinoma. To investigate expression of the co-stimulatory molecules CD80 (B7-1) and CD86 (B7-2) on tumor-associated dend...

  9. Detection and partial characterization of a midlamina lucida-hemidesmosome-associated antigen (19-DEJ-1) present within human skin

    DEFF Research Database (Denmark)

    Fine, J D; Horiguchi, Y; Jester, J;

    1989-01-01

    A murine anti-human monoclonal antibody (19-DEJ-1) has been produced that binds to basement membranes (BMs) of the dermoepidermal junction and arrector pili muscles but not to either dermal glandular or vascular BMs. 19-DEJ-1 also recognizes BMs underneath epithelia of buccal mucosa, tongue......, esophagus, cervix, and cornea, and BMs surrounding smooth muscle in medium-sized vessels, placenta, uterus, and esophagus. When 16 human fetal skins (aged 54-142 gestational days) were examined, the antigen was first detected at 81 days. Using immunoperoxidase and immunogold staining techniques, indirect...... cells, 19-DEJ-1 monoclonal antibody specifically precipitated 2.75% of the total radiolabeled proteoglycans produced in culture supernatant and isolated by anion exchange chromatography. On the basis of our present findings, we conclude that 19-DEJ-1 monoclonal antibody defines a unique primate...

  10. An Alternative and Effective HIV Vaccination Approach Based on Inhibition of Antigen Presentation Attenuators in Dendritic Cells.

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available BACKGROUND: Current efforts to develop HIV vaccines that seek to stimulate immune responses have been disappointing, underscoring the inability of natural immune responses to control HIV-1 infection. Here we tested an alternative strategy to induce anti-HIV immune responses by inhibiting a host's natural immune inhibitor. METHODS AND FINDINGS: We used small interfering RNA (siRNA to inhibit suppressor of cytokine signaling (SOCS 1, a key negative regulator of the JAK/STAT pathway, and investigated the effect of this silencing on the ability of dendritic cells (DCs to induce anti-HIV-1 immunity. We found that SOCS1-silenced DCs broadly induced enhanced HIV-1 envelope (Env-specific CD8(+ cytotoxic T lymphocytes and CD4(+ T helper cells, as well as antibody responses, in mice. Importantly, SOCS1-silenced DCs were more resistant to HIV Env-mediated suppression and were capable of inducing memory HIV Env-specific antibody and T cell responses. SOCS1-restricted signaling, as well as production of proinflammatory cytokines such as interleukin-12 by DCs, play a critical role in regulating the anti-HIV immune response. Furthermore, the potency of HIV DNA vaccination is significantly enhanced by coimmunization with SOCS1 siRNA expressor DNA. CONCLUSIONS: This study demonstrates that SOCS1 functions as an antigen presentation attenuator to control both HIV-1-specific humoral and cellular responses. This study represents the first, to our knowledge, attempt to elicit HIV-specific T cell and antibody responses by inhibiting a host's antigen presentation attenuator, which may open a new and alternative avenue to develop effective therapeutic and prophylactic HIV vaccines.

  11. Neoantigen Load, Antigen Presentation Machinery, and Immune Signatures Determine Prognosis in Clear Cell Renal Cell Carcinoma.

    Science.gov (United States)

    Matsushita, Hirokazu; Sato, Yusuke; Karasaki, Takahiro; Nakagawa, Tohru; Kume, Haruki; Ogawa, Seishi; Homma, Yukio; Kakimi, Kazuhiro

    2016-05-01

    Tumors commonly harbor multiple genetic alterations, some of which initiate tumorigenesis. Among these, some tumor-specific somatic mutations resulting in mutated protein have the potential to induce antitumor immune responses. To examine the relevance of the latter to immune responses in the tumor and to patient outcomes, we used datasets of whole-exome and RNA sequencing from 97 clear cell renal cell carcinoma (ccRCC) patients to identify neoepitopes predicted to be presented by each patient's autologous HLA molecules. We found that the number of nonsilent or missense mutations did not correlate with patient prognosis. However, combining the number of HLA-restricted neoepitopes with the cell surface expression of HLA or β2-microglobulin(β2M) revealed that an A-neo(hi)/HLA-A(hi) or ABC-neo(hi)/β2M(hi) phenotype correlated with better clinical outcomes. Higher expression of immune-related genes from CD8 T cells and their effector molecules [CD8A, perforin (PRF1) and granzyme A (GZMA)], however, did not correlate with prognosis. This may have been due to the observed correlation of these genes with the expression of other genes that were associated with immunosuppression in the tumor microenvironment (CTLA-4, PD-1, LAG-3, PD-L1, PD-L2, IDO1, and IL10). This suggested that abundant neoepitopes associated with greater antitumor effector immune responses were counterbalanced by a strongly immunosuppressive microenvironment. Therefore, immunosuppressive molecules should be considered high-priority targets for modulating immune responses in patients with ccRCC. Blockade of these molecular pathways could be combined with immunotherapies targeting neoantigens to achieve synergistic antitumor activity. Cancer Immunol Res; 4(5); 463-71. ©2016 AACR. PMID:26980598

  12. Influenza A virus infection of human primary dendritic cells impairs their ability to cross-present antigen to CD8 T cells.

    Science.gov (United States)

    Smed-Sörensen, Anna; Chalouni, Cécile; Chatterjee, Bithi; Cohn, Lillian; Blattmann, Peter; Nakamura, Norihiro; Delamarre, Lélia; Mellman, Ira

    2012-01-01

    Influenza A virus (IAV) infection is normally controlled by adaptive immune responses initiated by dendritic cells (DCs). We investigated the consequences of IAV infection of human primary DCs on their ability to function as antigen-presenting cells. IAV was internalized by both myeloid DCs (mDCs) and plasmacytoid DCs but only mDCs supported viral replication. Although infected mDCs efficiently presented endogenous IAV antigens on MHC class II, this was not the case for presentation on MHC class I. Indeed, cross-presentation by uninfected cells of minute amounts of endocytosed, exogenous IAV was -300-fold more efficient than presentation of IAV antigens synthesized by infected cells and resulted in a statistically significant increase in expansion of IAV-specific CD8 T cells. Furthermore, IAV infection also impaired cross-presentation of other exogenous antigens, indicating that IAV infection broadly attenuates presentation on MHC class I molecules. Our results suggest that cross-presentation by uninfected mDCs is a preferred mechanism of antigen-presentation for the activation and expansion of CD8 T cells during IAV infection. PMID:22412374

  13. Influenza A virus infection of human primary dendritic cells impairs their ability to cross-present antigen to CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Anna Smed-Sörensen

    Full Text Available Influenza A virus (IAV infection is normally controlled by adaptive immune responses initiated by dendritic cells (DCs. We investigated the consequences of IAV infection of human primary DCs on their ability to function as antigen-presenting cells. IAV was internalized by both myeloid DCs (mDCs and plasmacytoid DCs but only mDCs supported viral replication. Although infected mDCs efficiently presented endogenous IAV antigens on MHC class II, this was not the case for presentation on MHC class I. Indeed, cross-presentation by uninfected cells of minute amounts of endocytosed, exogenous IAV was -300-fold more efficient than presentation of IAV antigens synthesized by infected cells and resulted in a statistically significant increase in expansion of IAV-specific CD8 T cells. Furthermore, IAV infection also impaired cross-presentation of other exogenous antigens, indicating that IAV infection broadly attenuates presentation on MHC class I molecules. Our results suggest that cross-presentation by uninfected mDCs is a preferred mechanism of antigen-presentation for the activation and expansion of CD8 T cells during IAV infection.

  14. Host MHC class II+ antigen-presenting cells and CD4 cells are required for CD8-mediated graft-versus-leukemia responses following delayed donor leukocyte infusions

    OpenAIRE

    Chakraverty, Ronjon; Eom, Hyeon-Seok; Sachs, Jessica; Buchli, Jennifer; Cotter, Pete; Hsu, Richard; Zhao, Guiling; Sykes, Megan

    2006-01-01

    Following bone marrow transplantation, delayed donor leukocyte infusions (DLIs) can induce graft-versus-leukemia (GVL) effects without graft-versus-host disease (GVHD). These antitumor responses are maximized by the presence of host hematopoietic antigen-presenting cells (APCs) at the time of DLI. Using a tumor-protection model, we demonstrate here that GVL activity following administration of DLIs to established mixed chimeras is dependent primarily on reactivity to allogeneic MHC antigens r...

  15. Forcing Tumor Cells to Present Their Own Tumor Antigens to the Immune System: a Necessary Design for an Efficient Tumor Immunotherapy

    Institute of Scientific and Technical Information of China (English)

    RobertE.Humphreys; GildaG.Hillman; EricyonHofe; MinzhenXu

    2004-01-01

    The general principle for tumor cells to escape from immune surveillance is to prevent tumor antigens from being recognized by the immune system. Many methods have been developed to increase the immunogenecity of the tumor cells. The most efficient methods are able to force tumor cells to present their own tumor antigens to the immune system. Stimulating Th cells by converting tumor cells into MHC class II+/Ii- antigen presenting cells is one of the most efficient technologies. Using antisense methods, we suppress the expression of the Ii protein that normally co-expresses with MHC class II molecules and blocks the antigenic peptide binding site of MHC class II molecules during synthesis in the endoplasmic reticulum. In such tumor cells, the"unprotected" MHC class II molecules pick up endogenous tumor antigenic peptides, which have been transported into the ER for binding to MHC class I molecules. Simultaneous presentation of tumor antigens by both MHC class I and II molecules generates a robust and long-lasting anti-tumor immune response. MHC class II+/Ii- tumor cells are potent tumor cell vaccines and also cure a significant number of animals with renal and prostate tumors. We have developed analogous human gene vectors that are suitable for most patients and cancers.

  16. Changes in antigen-presenting cell function in the spleen and lymph nodes of ultraviolet-irradiated mice

    International Nuclear Information System (INIS)

    It has been previously reported that mice exposed to ultraviolet (UV) radiation exhibit a decrease in splenic antigen-presenting cell (APC) function. The results presented here confirm this observation and further demonstrate that animals exposed daily to UV for extended periods of time (5 weeks instead of 6 days) no longer exhibit this depressed capability. In spite of the depression in splenic APC activity found in 6-day UV-irradiated mice, lymph node APC function from these same animals was elevated compared with that found in the lymph nodes from normal animals. Lymph node APC activity in animals that were splenectomized prior to the UV irradiation, however, was not enhanced over controls. Treatment of animals with a chemical irritant (turpentine) also caused a depression in splenic APC function without modifying lymph node activity. Collectively, our findings suggest that the observed decrease in splenic APC activity, found after the first week of UV exposures, may be attributable to the migration of splenic APC to peripheral lymphoid tissue which drain the site of epidermal inflammation

  17. Myeloid Cell Nuclear Differentiation Antigen (MNDA) Expression Distinguishes Extramedullary Presentations of Myeloid Leukemia From Blastic Plasmacytoid Dendritic Cell Neoplasm.

    Science.gov (United States)

    Johnson, Ryan C; Kim, Jinah; Natkunam, Yasodha; Sundram, Uma; Freud, Aharon G; Gammon, Bryan; Cascio, Michael J

    2016-04-01

    Myeloid neoplasms constitute one of the most common malignancies in adults. In most cases these proliferations initially manifest in the blood and marrow; however, extramedullary involvement may precede blood or marrow involvement in a subset of cases, making a definitive diagnosis challenging by morphologic and immunohistochemical assessment alone. Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare, aggressive entity that frequently presents in extramedullary sites and can show morphologic and immunophenotypic overlap with myeloid neoplasms. Given that BPDCN and myeloid neoplasms may both initially present in extramedullary sites and that novel targeted therapies may be developed that exploit the unique molecular signature of BPDCN, new immunophenotypic markers that can reliably separate myeloid neoplasms from BPDCN are desirable. We evaluated the utility of myeloid cell nuclear differentiation antigen (MNDA) expression in a series of extramedullary myeloid leukemias (EMLs) and BPDCN. Forty biopsies containing EML and 19 biopsies containing BPDCN were studied by MNDA immunohistochemistry. The majority of myeloid neoplasms showed nuclear expression of MNDA (65%). In contrast, all cases of BPDCN lacked MNDA expression. These findings show that MNDA is expressed in the majority of EMLs and support the inclusion of MNDA immunohistochemistry in the diagnostic evaluation of blastic hematopoietic infiltrates, particularly when the differential diagnosis is between myeloid leukemia and BPDCN. PMID:26796502

  18. Balancing selection maintains a form of ERAP2 that undergoes nonsense-mediated decay and affects antigen presentation.

    Directory of Open Access Journals (Sweden)

    Aida M Andrés

    2010-10-01

    Full Text Available A remarkable characteristic of the human major histocompatibility complex (MHC is its extreme genetic diversity, which is maintained by balancing selection. In fact, the MHC complex remains one of the best-known examples of natural selection in humans, with well-established genetic signatures and biological mechanisms for the action of selection. Here, we present genetic and functional evidence that another gene with a fundamental role in MHC class I presentation, endoplasmic reticulum aminopeptidase 2 (ERAP2, has also evolved under balancing selection and contains a variant that affects antigen presentation. Specifically, genetic analyses of six human populations revealed strong and consistent signatures of balancing selection affecting ERAP2. This selection maintains two highly differentiated haplotypes (Haplotype A and Haplotype B, with frequencies 0.44 and 0.56, respectively. We found that ERAP2 expressed from Haplotype B undergoes differential splicing and encodes a truncated protein, leading to nonsense-mediated decay of the mRNA. To investigate the consequences of ERAP2 deficiency on MHC presentation, we correlated surface MHC class I expression with ERAP2 genotypes in primary lymphocytes. Haplotype B homozygotes had lower levels of MHC class I expressed on the surface of B cells, suggesting that naturally occurring ERAP2 deficiency affects MHC presentation and immune response. Interestingly, an ERAP2 paralog, endoplasmic reticulum aminopeptidase 1 (ERAP1, also shows genetic signatures of balancing selection. Together, our findings link the genetic signatures of selection with an effect on splicing and a cellular phenotype. Although the precise selective pressure that maintains polymorphism is unknown, the demonstrated differences between the ERAP2 splice forms provide important insights into the potential mechanism for the action of selection.

  19. Nano-clustering of ligands on surrogate antigen presenting cells modulates T cell membrane adhesion and organization.

    Science.gov (United States)

    Dillard, Pierre; Pi, Fuwei; Lellouch, Annemarie C; Limozin, Laurent; Sengupta, Kheya

    2016-03-14

    We investigate the adhesion and molecular organization of the plasma membrane of T lymphocytes interacting with a surrogate antigen presenting cell comprising glass supported ordered arrays of antibody (α-CD3) nano-dots dispersed in a non-adhesive matrix of polyethylene glycol (PEG). The local membrane adhesion and topography, as well as the distribution of the T cell receptors (TCRs) and the kinase ZAP-70, are influenced by dot-geometry, whereas the cell spreading area is determined by the overall average density of the ligands rather than specific characteristics of the dots. TCR clusters are recruited preferentially to the nano-dots and the TCR cluster size distribution has a weak dot-size dependence. On the patterns, the clusters are larger, more numerous, and more enriched in TCRs, as compared to the homogeneously distributed ligands at comparable concentrations. These observations support the idea that non-ligated TCRs residing in the non-adhered parts of the proximal membrane are able to diffuse and enrich the existing clusters at the ligand dots. However, long distance transport is impaired and cluster centralization in the form of a central supramolecular cluster (cSMAC) is not observed. Time-lapse imaging of early cell-surface contacts indicates that the ZAP-70 microclusters are directly recruited to the site of the antibody dots and this process is concomitant with membrane adhesion. These results together point to a complex interplay of adhesion, molecular organization and activation in response to spatially modulated stimulation. PMID:26887857

  20. Immunomodulation of Lactobacillus rhamnosus GG (LGG)-derived soluble factors on antigen-presenting cells of healthy blood donors.

    Science.gov (United States)

    Fong, Fiona Long Yan; Kirjavainen, Pirkka V; El-Nezami, Hani

    2016-01-01

    Lactobacillus rhamnosus GG (LGG) cells have been shown to promote type-1 immune responsiveness; however knowledge of immunomodulation of soluble factors secreted by LGG is limited. This is the first study to investigate whether LGG soluble factors promote a comparable immune responsiveness as the bacterial cells. Both treatments - LGG conditioned medium with (CM + LGG) or without (CM) LGG cells, in this study increased expression of several toll-like receptors (TLRs) in all studied cell types and antigen presentation-associated receptor HLA-DR in macrophages and "intermediate" monocytes; but decreased that of activation markers on monocytes and macrophages and production of IL-10, IL-12 and TNFα in macrophages. In co-culture with mononuclear cells, CM increased Th1-type cytokine profile but not as pronounced as CM + LGG. This study suggests that LGG soluble factors exert similar immunomodulatory effects as the intact cells, but cells may be required for optimal type-1 immune responsiveness polarizing capacity of this probiotic strain. PMID:26961406

  1. Intracellular transport of MHC class II and associated invariant chain in antigen presenting cells from AP-3-deficient mocha mice.

    Science.gov (United States)

    Sevilla, L M; Richter, S S; Miller, J

    2001-06-15

    MHC class II-restricted antigen presentation requires trafficking of newly synthesized class II-invariant chain complexes from the trans-Golgi network to endosomal, peptide-loading compartments. This transport is mediated by dileucine-like motifs within the cytosolic tail of the invariant chain. Although these signals have been well characterized, the cytosolic proteins that interact with these dileucine signals and mediate Golgi sorting and endosomal transport have not been identified. Recently, an adaptor complex, AP-3, has been identified that interacts with dileucine motifs and mediates endosomal/lysosomal transport in yeast, Drosophila, and mammals. In this report, we have assessed class II-invariant chain trafficking in a strain of mice (mocha) which lacks expression of AP-3. Our studies demonstrate that the lack of AP-3 does not affect the kinetics of invariant chain degradation, the route of class II-invariant chain transport, or the rate and extent of class II-peptide binding as assessed by the generation of SDS-stable dimers. The possible role of other known or unknown adaptor complexes in class II-invariant chain transport is discussed. PMID:11520080

  2. Immunologic effects of whole body ultraviolet (uv) irradiation. II. Defect in splenic adherent cell antigen presentation for stimulation of T cell proliferation

    International Nuclear Information System (INIS)

    Ultraviolet (uv) irradiation has been shown to alter many parameters of the immunologic reactivity of mice. The altered responsiveness of uv-irradiated mice, as measured by delayed-type hypersensitivity (DTH) and primary in vitro plaque-forming cell (PFC) responses to T-dependent antigens, has recently been correlated with a functional defect in the splenic adherent cell population of these animals. The present studies describe a model of this altered responsiveness, which allows further clarification of the effects of external uv irradiation on the splenic antigen-presenting cell (APC) in its interactions with T cells

  3. Lung cancer-associated tumor antigens and the present status of immunotherapy against non-small-cell lung cancer

    International Nuclear Information System (INIS)

    Despite recent advances in surgery, irradiation, and chemotherapy, the prognosis of patients with lung cancer is still poor. Therefore, the development and application of new therapeutic strategies are essential for improving the prognosis of this disease. Significant progress in our understanding of tumor immunology and molecular biology has allowed us to identify the tumor-associated antigens recognized by cytotoxic T lymphocytes. Immune responses and tumor-associated antigens against not only malignant melanoma but also lung cancer have been elucidated at the molecular level. In a theoretical sense, tumor eradication is considered possible through antigen-based immunotherapy against such diseases. However, many clinical trials of cancer vaccination with defined tumor antigens have resulted in objective clinical responses in only a small number of patients. Tumor escape mechanisms from host immune surveillance remain a major obstacle for cancer immunotherapy. A better understanding of the immune escape mechanisms employed by tumor cells is necessary before we can develop a more effective immunotherapeutic approach to lung cancer. We review recent studies regarding the identification of tumor antigens in lung cancer, tumor immune escape mechanisms, and clinical vaccine trials in lung cancer. (author)

  4. Modeling the presentation of C3d-coated antigen by B lymphocytes: enhancement by CR1/2-BCR co-ligation is selective for the co-ligating antigen.

    Science.gov (United States)

    Prechl, József; Baiu, Dana C; Horváth, Attila; Erdei, Anna

    2002-03-01

    We have used a set of single-chain variable fragment antibodies (sc) genetically fused with an influenza hemagglutinin-derived peptide as a means to investigate the role of CR1 and CR2 in antigen presentation by B cells. When incubated with the B cell lymphoma 2PK3, peptide-containing sc specific for either CR1 or CR1/2 mediated activation of the hemagglutinin peptide-specific T cell line IP-12-7, as assessed by IL-2 production. Efficient presentation was dependent on the binding of the constructs to CR1/2, implying that receptor-mediated endocytosis is responsible for the effect. Cross-linkage of CR1/2 or CD19 by mAb did not increase the extent of T cell activation. However, when CR1/2 was co-ligated with the BCR--using either polyclonal goat anti-mouse IgG or recombinant protein LA--the antigen concentration required to activate T cells decreased by two orders of magnitude. Moreover, this enhancement was selective for the antigen included in these complexes and did not affect the presentation of a free peptide or of antigen bound to CR1/2 excluded from the complexes. These results suggest that B cells may bind various C3d-coated antigens at a time, but only the one which reacts with the BCR will be processed with high efficiency. This mechanism may ensure the specificity of cognate T cell help. PMID:11867560

  5. Antigen Delivery with Poly(Propylacrylic Acid) Conjugation Enhances MHC-1 Presentation and T-Cell Activation

    OpenAIRE

    Flanary, Suzanne; Hoffman, Allan S.; Stayton, Patrick S.

    2009-01-01

    While many infectious diseases are controlled by vaccine strategies, important limitations continue to motivate the development of better antigen delivery systems. This study focuses on the use of a pH-sensitive polymeric carrier based on poly(propylacrylic acid) (PPAA) to address the need for more potent CD8 cytotoxic T-cell (CTL) responses. An MHC-1/CD8 CTL cell model system with ovalbumin as the protein antigen was used to test whether PPAA could enhance the delivery of ovalbumin into the ...

  6. Targeting human dendritic cells via DEC-205 using PLGA nanoparticles leads to enhanced cross-presentation of a melanoma-associated antigen

    Directory of Open Access Journals (Sweden)

    Saluja SS

    2014-11-01

    Full Text Available Sandeep S Saluja,1 Douglas J Hanlon,1 Fiona A Sharp,2 Enping Hong,2 David Khalil,1 Eve Robinson,1 Robert Tigelaar,1 Tarek M Fahmy,2,3 Richard L Edelson1 1Department of Dermatology, Yale University School of Medicine, 2Department of Biomedical Engineering, Yale University, 3Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA Abstract: Targeting antigen to dendritic cells (DCs is a powerful and novel strategy for vaccination. Priming or loading DCs with antigen controls whether subsequent immunity will develop and hence whether effective vaccination can be achieved. The goal of our present work was to increase the potency of DC-based antitumor vaccines by overcoming inherent limitations associated with antigen stability and cross-presentation. Nanoparticles prepared from the biodegradable polymer poly(lactic-co-glycolic acid have been extensively used in clinical settings for drug delivery and are currently the subject of intensive investigation as antigen delivery vehicles for vaccine applications. Here we describe a nanoparticulate delivery system with the ability to simultaneously carry a high density of protein-based antigen while displaying a DC targeting ligand on its surface. Utilizing a targeting motif specific for the DC-associated surface ligand DEC-205, we show that targeted nanoparticles encapsulating a MART-127–35 peptide are both internalized and cross-presented with significantly higher efficiency than isotype control-coated nanoparticles in human cells. In addition, the DEC-205-labeled nanoparticles rapidly escape from the DC endosomal compartment and do not colocalize with markers of early (EEA-1 or late endosome/lysosome (LAMP-1. This indicates that encapsulated antigens delivered by nanoparticles may have direct access to the class I cytoplasmic major histocompatibility complex loading machinery, overcoming the need for “classical” cross-presentation and facilitating heightened DC

  7. 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

  8. Tunable chemokine production by antigen presenting dendritic cells in response to changes in regulatory T cell frequency in mouse reactive lymph nodes.

    Directory of Open Access Journals (Sweden)

    Valentina Dal Secco

    Full Text Available BACKGROUND: Although evidence exists that regulatory T cells (Tregs can suppress the effector phase of immune responses, it is clear that their major role is in suppressing T cell priming in secondary lymphoid organs. Recent experiments using two photon laser microscopy indicate that dendritic cells (DCs are central to Treg cell function and that the in vivo mechanisms of T cell regulation are more complex than those described in vitro. PRINCIPAL FINDINGS: Here we have sought to determine whether and how modulation of Treg numbers modifies the lymph node (LN microenvironment. We found that pro-inflammatory chemokines -- CCL2 (MCP-1 and CCL3 (MIP-la -- are secreted in the LN early (24 h after T cell activation, that this secretion is dependent on antigen-specific DC-T cell interactions, and that it was inversely related to the frequency of Tregs specific for the same antigen. Furthermore, we demonstrate that Tregs modify the chemoattractant properties of antigen-presenting DCs, which, as the frequency of Tregs increases, fail to produce CCL2 and CCL3 and to attract antigen-specific T cells. CONCLUSIONS: These results substantiate a major role of Tregs in LN patterning during antigen-specific immune responses.

  9. Particle-based transcutaneous administration of HIV-1 p24 protein to human skin explants and targeting of epidermal antigen presenting cells.

    Science.gov (United States)

    Rancan, Fiorenza; Amselgruber, Sarah; Hadam, Sabrina; Munier, Sevérine; Pavot, Vincent; Verrier, Bernard; Hackbarth, Steffen; Combadiere, Behazine; Blume-Peytavi, Ulrike; Vogt, Annika

    2014-02-28

    Transcutaneous immunization is a promising vaccination strategy for the treatment of infectious diseases and cancer. In this study, we investigate the combination of cyanoacrylate skin surface stripping (CSSS) and particle-based antigen delivery to target the HIV-1 p24 protein to skin antigen presenting cells (APC). The CSSS treatment pre-activates skin APC and opens hair follicles, where protein-loaded particles accumulate and allow for sustained delivery of the loaded antigen to perifollicular APC. We found that poly-lactic acid (PLA) and polystyrene (PS) particles targeted the adsorbed HIV-1 p24 protein to the hair follicles. Small amounts of PS and PLA particles were found to translocate to the epidermis and be internalized by skin cells, whereas most of the particles aggregated in the hair follicle canal, where they released the loaded antigen. The p24 protein diffused to the epidermis and dermis and was detected in skin cells, especially in Langerhans cells and dermal dendritic cells. Furthermore, the combination of CSSS and particle-based delivery resulted in activation and maturation of Langerhans cells (HLA-DR, CD80 and CD83). We conclude that particle-based antigen delivery across partially disrupted skin barrier is a feasible and effective approach to needle-free transcutaneous vaccination. PMID:24384300

  10. Construction of a triple modified p53 containing DNA vaccine to enhance processing and presentation of the p53 antigen

    NARCIS (Netherlands)

    Hospers, Geke A. P.; Meijer, Coby; Dam, Wendy A.; Roossink, Frank; Mulder, Nanno H.

    2009-01-01

    More effective and less toxic treatments are urgently needed in the treatment of patients with cancer. The turnout suppressor protein p53 is a tumour-associated antigen that could serve that purpose when applied in an immunologic approval to cancer. It is mutated in similar to 50% of the tumours res

  11. Analysis of detergent-free lipid rafts isolated from CD4+ T cell line: interaction with antigen presenting cells promotes coalescing of lipid rafts

    Directory of Open Access Journals (Sweden)

    Kennedy Colleen

    2011-12-01

    Full Text Available Abstract Background Lipid rafts present on the plasma membrane play an important role in spatiotemporal regulation of cell signaling. Physical and chemical characterization of lipid raft size and assessment of their composition before, and after cell stimulation will aid in developing a clear understanding of their regulatory role in cell signaling. We have used visual and biochemical methods and approaches for examining individual and lipid raft sub-populations isolated from a mouse CD4+ T cell line in the absence of detergents. Results Detergent-free rafts were analyzed before and after their interaction with antigen presenting cells. We provide evidence that the average diameter of lipid rafts isolated from un-stimulated T cells, in the absence of detergents, is less than 100 nm. Lipid rafts on CD4+ T cell membranes coalesce to form larger structures, after interacting with antigen presenting cells even in the absence of a foreign antigen. Conclusions Findings presented here indicate that lipid raft coalescence occurs during cellular interactions prior to sensing a foreign antigen.

  12. 1,25-Dihydroxyvitamin D3 inhibits proliferation but not the suppressive function of regulatory T cells in the absence of antigen-presenting cells.

    NARCIS (Netherlands)

    Khoo, A.L.; Joosten, I.; Michels, M.; Woestenenk, R.M.; Preijers, F.W.M.B.; He, X.; Netea, M.G.; Ven, A.J.A.M. van der; Koenen, H.J.P.M.

    2011-01-01

    Vitamin D3 is known to induce regulatory T (Treg) cells by rendering antigen-presenting cells tolerogenic, its direct effect on human naturally occurring Treg cells is unclear. Here, we investigated if and how 1,25-dihydroxyvitamin D(3) [1,25(OH)2D3] can directly affect the proliferation and functio

  13. Parasite Manipulation of the Invariant Chain and the Peptide Editor H2-DM Affects Major Histocompatibility Complex Class II Antigen Presentation during Toxoplasma gondii Infection.

    Science.gov (United States)

    Leroux, Louis-Philippe; Nishi, Manami; El-Hage, Sandy; Fox, Barbara A; Bzik, David J; Dzierszinski, Florence S

    2015-10-01

    Toxoplasma gondii is an obligate intracellular protozoan parasite. This apicomplexan is the causative agent of toxoplasmosis, a leading cause of central nervous system disease in AIDS. It has long been known that T. gondii interferes with major histocompatibility complex class II (MHC-II) antigen presentation to attenuate CD4(+) T cell responses and establish persisting infections. Transcriptional downregulation of MHC-II genes by T. gondii was previously established, but the precise mechanisms inhibiting MHC-II function are currently unknown. Here, we show that, in addition to transcriptional regulation of MHC-II, the parasite modulates the expression of key components of the MHC-II antigen presentation pathway, namely, the MHC-II-associated invariant chain (Ii or CD74) and the peptide editor H2-DM, in professional antigen-presenting cells (pAPCs). Genetic deletion of CD74 restored the ability of infected dendritic cells to present a parasite antigen in the context of MHC-II in vitro. CD74 mRNA and protein levels were, surprisingly, elevated in infected cells, whereas MHC-II and H2-DM expression was inhibited. CD74 accumulated mainly in the endoplasmic reticulum (ER), and this phenotype required live parasites, but not active replication. Finally, we compared the impacts of genetic deletion of CD74 and H2-DM genes on parasite dissemination toward lymphoid organs in mice, as well as activation of CD4(+) T cells and interferon gamma (IFN-γ) levels during acute infection. Cyst burdens and survival during the chronic phase of infection were also evaluated in wild-type and knockout mice. These results highlight the fact that the infection is influenced by multiple levels of parasite manipulation of the MHC-II antigen presentation pathway. PMID:26195549

  14. Aetiology and pathogenesis of reactive arthritis: role of non-antigen-presenting effects of HLA-B27

    OpenAIRE

    Vähämiko, Sanna; Penttinen, Markus A.; Granfors, Kaisa

    2005-01-01

    Spondyloarthropathies are inflammatory diseases closely associated with human leukocyte antigen (HLA)-B27 by unknown mechanisms. One of these diseases is reactive arthritis (ReA), which is typically triggered by Gram-negative bacteria, which have lipopolysaccharide as an integral component of their outer membrane. Several findings in vivo and in vitro obtained from patients with ReA and from different model systems suggest that HLA-B27 modulates the interaction between ReA-triggering bacteria...

  15. Mitochondrial H2O2 in Lung Antigen-Presenting Cells Blocks NF-κB Activation to Prevent Unwarranted Immune Activation

    Directory of Open Access Journals (Sweden)

    Anupriya Khare

    2016-05-01

    Full Text Available Inhalation of environmental antigens such as allergens does not always induce inflammation in the respiratory tract. While antigen-presenting cells (APCs, including dendritic cells and macrophages, take up inhaled antigens, the cell-intrinsic molecular mechanisms that prevent an inflammatory response during this process, such as activation of the transcription factor NF-κB, are not well understood. Here, we show that the nuclear receptor PPARγ plays a critical role in blocking NF-κB activation in response to inhaled antigens to preserve immune tolerance. Tolerance induction promoted mitochondrial respiration, generation of H2O2, and suppression of NF-κB activation in WT, but not PPARγ-deficient, APCs. Forced restoration of H2O2 in PPARγ-deficient cells suppressed IκBα degradation and NF-κB activation. Conversely, scavenging reactive oxygen species from mitochondria promoted IκBα degradation with loss of regulatory and promotion of inflammatory T cell responses in vivo. Thus, communication between PPARγ and the mitochondria maintains immune quiescence in the airways.

  16. Presentation of human minor histocompatibility antigens by HLA-B35 and HLA-B38 molecules

    International Nuclear Information System (INIS)

    Cytotoxic T lymphocyte (CTL) clones specific for human minor histocompatibility antigens (hmHAs) were produced from a patient who had been grafted with the kidneys from his mother and two HLA-identical sisters. Of eight CTL clones generated, four recognized an hmHA (hmHA-1) expressed on cells from the mother and sister 3 (second donor); two recognized another antigen (hmHA-2) on cells from the father, sister (third donor), and sister 3; and the remaining two clones recognized still another antigen (hmHA-3) on cells from the father and sister 3. Panel studies revealed that CTL recognition of hmHA-1 was restricted by HLA-B35 and that of hmHA-2 and hmHA-3 was restricted by HLA-B38. The HLA-B35 restriction of the hmHA-1 -specific CTL clones was substantiated by the fact that they killed HLA-A null/HLA-B null Hmy2CIR targets transfected with HLA-B35 but not HLA-B51, -Bw52, or -Bw53 transfected Hmy2CIR targets. These data demonstrated that the five amino acids substitutions on the α1 domain between HLA-B35 and -Bw53, which are associated with Bw4/Bw6 epitopes, play a critical role in the relationship of hmHA-1 to HLA-B35 molecules. The fact that the hmHA-1-specific CTLs failed to kill Hmy2CIR cells expressing HLA-B35/51 chimeric molecules composed of the α1 domain of HLA-B35 and other domains of HLA-B51 indicated that eight residues on the α2 domain also affect the interaction of hmHA-1 and the HLA-B35 molecules

  17. The HIV-1 gp120/V3 modifies the response of uninfected CD4 T cells to antigen presentation: mapping of the specific transcriptional signature

    Directory of Open Access Journals (Sweden)

    Spandidos Demetrios A

    2011-09-01

    Full Text Available Abstract Background The asymptomatic phase of HIV-1 infection is characterized by a progressive depletion of uninfected peripheral effector/memory CD4+ T cells that subsequently leads to immune dysfunction and AIDS symptoms. We have previously demonstrated that the presence of specific gp120/V3 peptides during antigen presentation can modify the activation of normal T-cells leading to altered immune function. The aim of the present study was to map the specific transcriptional profile invoked by an HIV-1/V3 epitope in uninfected T cells during antigen presentation. Methods We exposed primary human peripheral blood monocytes to V3 lipopeptides using a liposome delivery system followed by a superantigen-mediated antigen presentation system. We then evaluated the changes in the T-cell transcriptional profile using oligonucleotide microarrays and performed Ingenuity Pathway Analysis (IPA and DAVID analysis. The results were validated using realtime PCR, FACS, Western blotting and immunofluorescence. Results Our results revealed that the most highly modulated transcripts could almost entirely be categorized as related to the cell cycle or transcriptional regulation. The most statistically significant enriched categories and networks identified by IPA were associated with cell cycle, gene expression, immune response, infection mechanisms, cellular growth, proliferation and antigen presentation. Canonical pathways involved in energy and cell cycle regulation, and in the co-activation of T cells were also enriched. Conclusions Taken together, these results document a distinct transcriptional profile invoked by the HIV-1/V3 epitope. These data could be invaluable to determine the underlying mechanism by which HIV-1 epitopes interfere with uninfected CD4+ T-cell function causing hyper proliferation and AICD.

  18. Human cytomegalovirus pp65- and immediate early 1 antigen-specific HLA class I-restricted cytotoxic T cell responses induced by cross-presentation of viral antigens.

    Science.gov (United States)

    Tabi, Z; Moutaftsi, M; Borysiewicz, L K

    2001-05-01

    Dendritic cells (DCs) play a pivotal role in the development of anti-viral CD8(+) CTL responses. This is straightforward if they are directly infected with virus, but is less clear in response to viruses that cannot productively infect DCS: Human CMV (HCMV) shows strain-specific cell tropism: fibroblast (Fb)-adapted laboratory strains (AD169) and recent clinical isolates do not infect DCs, whereas endothelial cell-adapted strains (TB40/E) result in productive lytic DC infection. However, we show here that uninfected DCs induce CD8(+) T cell cytotoxicity and IFN-gamma production against HCMV pp65 and immediate early 1 Ags following in vitro coculture with HCMV-AD169-infected Fbs, regardless of the HLA type of these FBS: CD8(+) T cell stimulation was inhibited by pretreatment of DCs with cytochalasin B or brefeldin A, indicating a phagosome/endosome to cytosol pathway. HCMV-infected Fbs were not apoptotic as measured by annexin V binding, and induction of apoptosis of infected Fbs in vitro did not augment CTL induction by DCs, suggesting a mechanism other than apoptosis in the initiation of cross-presentation. Furthermore, HCMV-infected Fbs provided a maturation signal for immature DCs during coculture, as evidenced by increased CD83 and HLA class II expression. Cross-presentation of HCMV Ags by host DCs enables these professional APCs to bypass some of the evasion mechanisms HCMV has developed to avoid T cell recognition. It may also serve to explain the presence of immediate early 1 Ag-specific CTLs in the face of pp65-induced inhibition of Ag presentation at the level of the infected cell. PMID:11313411

  19. Parasite Manipulation of the Invariant Chain and the Peptide Editor H2-DM Affects Major Histocompatibility Complex Class II Antigen Presentation during Toxoplasma gondii Infection

    OpenAIRE

    Leroux, Louis-Philippe; Nishi, Manami; El-Hage, Sandy; Fox, Barbara A.; Bzik, David J.; Dzierszinski, Florence S.

    2015-01-01

    Toxoplasma gondii is an obligate intracellular protozoan parasite. This apicomplexan is the causative agent of toxoplasmosis, a leading cause of central nervous system disease in AIDS. It has long been known that T. gondii interferes with major histocompatibility complex class II (MHC-II) antigen presentation to attenuate CD4+ T cell responses and establish persisting infections. Transcriptional downregulation of MHC-II genes by T. gondii was previously established, but the precise mechanisms...

  20. A Neoglycoconjugate Containing the Human Milk Sugar LNFPIII Drives Anti-Inflammatory Activation of Antigen Presenting Cells in a CD14 Dependent Pathway

    OpenAIRE

    Tundup, Smanla; Srivastava, Leena; Norberg, Thomas; Watford, Wendy; Harn, Donald

    2015-01-01

    The milk pentasaccharide LNFPIII has therapeutic action for metabolic and autoimmune diseases and prolongs transplant survival in mice when presented as a neoglycoconjugate. Within LNFPIII is the Lewis(x) trisaccharide, expressed by many helminth parasites. In humans, LNFPIII is found in human milk and also known as stage-specific embryonic antigen-1. LNFPIII-NGC drives alternative activation of macrophages and dendritic cells via NF kappa B activation in a TLR4 dependent mechanism. However, ...

  1. Autophagy and ATP-induced anti-apoptosis in antigen presenting cells (APC) follows the cytokine storm in patients after major trauma

    OpenAIRE

    Schneider, E Marion; Flacke, Sarah; Liu, Fengguang; Lorenz, Myriam R.; Schilling, Patricia; Nass, Max E.; Foehr, Karl J.; Huber-Lang, Markus; Weiss, Manfred E.

    2011-01-01

    Severe trauma and the systemic inflammatory response syndrome (SIRS) occur as a result of a cytokine storm which is in part due to ATP released from damaged tissue. This pathology also leads to increased numbers of immature antigen presenting cells (APC) sharing properties of dendritic cells (DC) or macrophages (MΦ). The occurrence of immature APC appears to coincide with the reactivation of herpes virus infections such as Epstein Barr virus (EBV). The aim of this study was the comparative an...

  2. Neonatal colonisation expands a specific intestinal antigen-presenting cell subset prior to CD4 T-cell expansion, without altering T-cell repertoire.

    Directory of Open Access Journals (Sweden)

    Charlotte F Inman

    Full Text Available Interactions between the early-life colonising intestinal microbiota and the developing immune system are critical in determining the nature of immune responses in later life. Studies in neonatal animals in which this interaction can be examined are central to understanding the mechanisms by which the microbiota impacts on immune development and to developing therapies based on manipulation of the microbiome. The inbred piglet model represents a system that is comparable to human neonates and allows for control of the impact of maternal factors. Here we show that colonisation with a defined microbiota produces expansion of mucosal plasma cells and of T-lymphocytes without altering the repertoire of alpha beta T-cells in the intestine. Importantly, this is preceded by microbially-induced expansion of a signal regulatory protein α-positive (SIRPα(+ antigen-presenting cell subset, whilst SIRPα(-CD11R1(+ antigen-presenting cells (APCs are unaffected by colonisation. The central role of intestinal APCs in the induction and maintenance of mucosal immunity implicates SIRPα(+ antigen-presenting cells as orchestrators of early-life mucosal immune development.

  3. Inhibition of antigen-presenting activity of dendritic cells resulting from UV irradiation of murine skin is restored by in vitro photorepair of cyclobutane pyrimidine dimers

    International Nuclear Information System (INIS)

    Exposing skin to UVB (280-320 nm) radiation suppresses contact hypersensitivity by a mechanism that involves an alteration in the activity of cutaneous antigen-presenting cells (APC). UV-induced DNA damage appears to be an important molecular trigger for this effect. The specific target cells in the skin that sustain DNA damage relevant to the immunosuppressive effect have yet to be identified. We tested the hypothesis that UV-induced DNA damage in the cutaneous APC was responsible for their impaired ability to present antigen after in vivo UV irradiation. Cutaneous APC were collected from the draining lymph nodes of UVB-irradiated, hapten-sensitized mice and incubated in vitro with liposomes containing a photolyase, which, upon absorption of photoreactivating light, splits UV-induced cyclobutane pyrimidine dimers. Photosome treatment followed by photoreactivating light reduced the number of dimer-containing APC, restored the in vivo antigen-presenting activity of the draining lymph node cells, and blocked the induction of suppressor T cells. Neither Photosomes nor photoreactivating light alone, nor photoreactivating light given before Photosomes, restored APC activity, and Photosomes treatment did not reverse the impairment of APC function when isopsoralen plus UVA (320-400 nm) radiation was used instead of UVB. These controls indicate that the restoration of APC function matched the requirements of Photosome-mediated DNA repair for dimers and post-treatment photoreactivating light. These results provide compelling evidence that it is UV-induced DNA damage in cutaneous APC that leads to reduced immune function

  4. Differential presentation of endogenous and exogenous hepatitis B surface antigens influences priming of CD8(+) T cells in an epitope-specific manner.

    Science.gov (United States)

    Riedl, Petra; Reiser, Michael; Stifter, Katja; Krieger, Jana; Schirmbeck, Reinhold

    2014-07-01

    Little is known about whether presentation of endogenous and exogenous hepatitis B virus (HBV) surface antigens on APCs targeted by vaccination and/or virus-harboring hepatocytes influences de novo priming of CD8(+) T cells. We showed that surface antigen-expressing transfectants exclusively display a K(b) /S190 epitope, whereas cells pulsed with recombinant surface particles (rSPs) exclusively present a K(b) /S208 epitope to CD8(+) T cells. The differential presentation of these epitopes largely reflects the selective, but not exclusive, priming of K(b) /S190- and K(b) /S208-specific T cells in C57BL/6 mice by endogenous/DNA- or exogenous/protein-based vaccines, respectively. Silencing the K(b) /S190 epitope (K(b) /S190V194F ) in antigen-expressing vectors rescued the presentation of the K(b) /S208 epitope in stable transfectants and significantly enhanced priming of K(b) /S208-specific T cells in C57BL/6 mice. A K(b) /S190-mediated immunodominance operating in surface antigen-expressing cells, but not in rSP-pulsed cells, led to an efficient suppression in the presentation of the K(b) /S208 epitope and a consequent decrease in the priming of K(b) /S208-specific T cells. This K(b) /S190-mediated immunodominance also operated in 1.4HBV-S(mut) transgenic (tg) hepatocytes selectively expressing endogenous surface antigens and allowed priming of K(b) /S208- but not K(b) /S190-specific T cells in 1.4HBV-S(mut) tg mice. However, IFN-γ(+) K(b) /S208-specific T cells could not inhibit HBV replication in the liver of 1.4HBV-S(mut) tg mice. These results have practical implications for the design of T-cell-stimulating therapeutic vaccines. PMID:24723392

  5. Diversity of natural self-derived ligands presented by different HLA class I molecules in transporter antigen processing-deficient cells.

    Directory of Open Access Journals (Sweden)

    Elena Lorente

    Full Text Available The transporter associated with antigen processing (TAP translocates the cytosol-derived proteolytic peptides to the endoplasmic reticulum lumen where they complex with nascent human leukocyte antigen (HLA class I molecules. Non-functional TAP complexes and viral or tumoral blocking of these transporters leads to reduced HLA class I surface expression and a drastic change in the available peptide repertoire. Using mass spectrometry to analyze complex human leukocyte antigen HLA-bound peptide pools isolated from large numbers of TAP-deficient cells, we identified 334 TAP-independent ligands naturally presented by four different HLA-A, -B, and -C class I molecules with very different TAP dependency from the same cell line. The repertoire of TAP-independent peptides examined favored increased peptide lengths and a lack of strict binding motifs for all four HLA class I molecules studied. The TAP-independent peptidome arose from 182 parental proteins, the majority of which yielded one HLA ligand. In contrast, TAP-independent antigen processing of very few cellular proteins generated multiple HLA ligands. Comparison between TAP-independent peptidome and proteome of several subcellular locations suggests that the secretory vesicle-like organelles could be a relevant source of parental proteins for TAP-independent HLA ligands. Finally, a predominant endoproteolytic peptidase specificity for Arg/Lys or Leu/Phe residues in the P(1 position of the scissile bond was found for the TAP-independent ligands. These data draw a new and intricate picture of TAP-independent pathways.

  6. Noncapsulated toxinogenic Bacillus anthracis presents a specific growth and dissemination pattern in naive and protective antigen-immune mice.

    Science.gov (United States)

    Glomski, Ian J; Corre, Jean-Philippe; Mock, Michèle; Goossens, Pierre L

    2007-10-01

    Bacillus anthracis is a spore-forming bacterium that causes anthrax. B. anthracis has three major virulence factors, namely, lethal toxin, edema toxin, and a poly-gamma-D-glutamic acid capsule. The toxins modulate host immune responses, and the capsule inhibits phagocytosis. With the goal of increasing safety, decreasing security concerns, and taking advantage of mammalian genetic tools and reagents, mouse models of B. anthracis infection have been developed using attenuated bacteria that produce toxins but no capsule. While these models have been useful in studying both toxinogenic infections and antitoxin vaccine efficacy, we questioned whether eliminating the capsule changed bacterial growth and dissemination characteristics. Thus, the progression of infection by toxinogenic noncapsulated B. anthracis was analyzed and compared to that by previously reported nontoxinogenic capsulated bacteria, using in vivo bioluminescence imaging. The influence of immunization with the toxin component protective antigen (PA) on the development of infection was also examined. The toxinogenic noncapsulated bacteria were initially confined to the cutaneous site of infection. Bacteria then progressed to the draining lymph nodes and, finally, late in the infection, to the lungs, kidneys, and frequently the gastrointestinal tract. There was minimal colonization of the spleen. PA immunization reduced bacterial growth from the outset and limited infection to the site of inoculation. These in vivo observations show that dissemination by toxinogenic noncapsulated strains differs markedly from that by nontoxinogenic capsulated strains. Additionally, PA immunization counters bacterial growth and dissemination in vivo from the onset of infection. PMID:17635863

  7. A molecular assembly system for presentation of antigens on the surface of HBc virus-like particles

    International Nuclear Information System (INIS)

    Hepatitis B virus-like particles, icosahedral structures formed by multiple core protein dimers, are promising immune-enhancing vaccine carriers for foreign antigens. Insertions into the surface-exposed immunodominant loop are especially immunogenic. However, the need to conserve the particulate structure to ensure high immunogenicity imposes restraints on the nature of the heterologous sequence that can be inserted. We propose a new approach to constructing HBc particles linked to the target epitopes that relies on non-covalent interactions between the epitope and pre-assembled unmodified HBc particles. Interaction was enabled by fusion of the epitope to the GSLLGRMKGA peptide, binding to the spike tips. This peptide may be used as a “binding tag” allowing in vitro construction of HBc particles carrying the target peptide. Such virus-like particles carrying multiple copies of the extracellular domain of the M2 protein of different influenza strains appeared to be highly immunogenic and protected immunised mice against a lethal influenza challenge.

  8. A molecular assembly system for presentation of antigens on the surface of HBc virus-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Blokhina, Elena A.; Kuprianov, Victor V. [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); Stepanova, Ludmila A.; Tsybalova, Ludmila M. [Research Institute of Influenza, Russian Federation Ministry of Health and Social Development, St. Petersburg (Russian Federation); Kiselev, Oleg I. [Research Institute of Influenza, Russian Federation Ministry of Health and Social Development, St. Petersburg (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation); Ravin, Nikolai V., E-mail: nravin@biengi.ac.ru [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation); Skryabin, Konstantin G. [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation)

    2013-01-20

    Hepatitis B virus-like particles, icosahedral structures formed by multiple core protein dimers, are promising immune-enhancing vaccine carriers for foreign antigens. Insertions into the surface-exposed immunodominant loop are especially immunogenic. However, the need to conserve the particulate structure to ensure high immunogenicity imposes restraints on the nature of the heterologous sequence that can be inserted. We propose a new approach to constructing HBc particles linked to the target epitopes that relies on non-covalent interactions between the epitope and pre-assembled unmodified HBc particles. Interaction was enabled by fusion of the epitope to the GSLLGRMKGA peptide, binding to the spike tips. This peptide may be used as a 'binding tag' allowing in vitro construction of HBc particles carrying the target peptide. Such virus-like particles carrying multiple copies of the extracellular domain of the M2 protein of different influenza strains appeared to be highly immunogenic and protected immunised mice against a lethal influenza challenge.

  9. Human macrophages and dendritic cells can equally present MART-1 antigen to CD8(+ T cells after phagocytosis of gamma-irradiated melanoma cells.

    Directory of Open Access Journals (Sweden)

    María Marcela Barrio

    Full Text Available Dendritic cells (DC can achieve cross-presentation of naturally-occurring tumor-associated antigens after phagocytosis and processing of dying tumor cells. They have been used in different clinical settings to vaccinate cancer patients. We have previously used gamma-irradiated MART-1 expressing melanoma cells as a source of antigens to vaccinate melanoma patients by injecting irradiated cells with BCG and GM-CSF or to load immature DC and use them as a vaccine. Other clinical trials have used IFN-gamma activated macrophage killer cells (MAK to treat cancer patients. However, the clinical use of MAK has been based on their direct tumoricidal activity rather than on their ability to act as antigen-presenting cells to stimulate an adaptive antitumor response. Thus, in the present work, we compared the fate of MART-1 after phagocytosis of gamma-irradiated cells by clinical grade DC or MAK as well as the ability of these cells to cross present MART-1 to CD8(+ T cells. Using a high affinity antibody against MART-1, 2A9, which specifically stains melanoma tumors, melanoma cell lines and normal melanocytes, the expression level of MART-1 in melanoma cell lines could be related to their ability to stimulate IFN-gamma production by a MART-1 specific HLA-A*0201-restricted CD8(+ T cell clone. Confocal microscopy with Alexa Fluor®(647-labelled 2A9 also showed that MART-1 could be detected in tumor cells attached and/or fused to phagocytes and even inside these cells as early as 1 h and up to 24 h or 48 h after initiation of co-cultures between gamma-irradiated melanoma cells and MAK or DC, respectively. Interestingly, MART-1 was cross-presented to MART-1 specific T cells by both MAK and DC co-cultured with melanoma gamma-irradiated cells for different time-points. Thus, naturally occurring MART-1 melanoma antigen can be taken-up from dying melanoma cells into DC or MAK and both cell types can induce specific CD8(+ T cell cross-presentation thereafter.

  10. Use of human antigen presenting cell gene array profiling to examine the effect of human T-cell leukemia virus type 1 Tax on primary human dendritic cells.

    Science.gov (United States)

    Ahuja, Jaya; Kampani, Karan; Datta, Suman; Wigdahl, Brian; Flaig, Katherine E; Jain, Pooja

    2006-02-01

    Human T-cell leukemia virus type 1 (HTLV-1) is etiologically linked to adult T-cell leukemia and a progressive demyelinating disorder termed HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). One of the most striking features of the immune response in HAM/TSP centers on the expansion of HTLV-1-specific CD8(+) cytotoxic T lymphocyte (CTL) compartment in the peripheral blood and cerebrospinal fluid. More than 90% of the HTLV-1-specific CTLs are directed against the viral Tax (11-19) peptide implying that Tax is available for immune recognition by antigen presenting cells, such as dendritic cells (DCs). DCs obtained from HAM/TSP patients have been shown to be infected with HTLV-1 and exhibit rapid maturation. Therefore, we hypothesized that presentation of Tax peptides by activated DCs to naIve CD8(+) T cells may play an important role in the induction of a Tax-specific CTL response and neurologic dysfunction. In this study, a pathway-specific antigen presenting cell gene array was used to study transcriptional changes induced by exposure of monocyte-derived DCs to extracellular HTLV-1 Tax protein. Approximately 100 genes were differentially expressed including genes encoding toll-like receptors, cell surface receptors, proteins involved in antigen uptake and presentation and adhesion molecules. The differential regulation of chemokines and cytokines characteristic of functional DC activation was also observed by the gene array analyses. Furthermore, the expression pattern of signal transduction genes was also significantly altered. These results have suggested that Tax-mediated DC gene regulation might play a critical role in cellular activation and the mechanisms resulting in HTLV-1-induced disease. PMID:16595374

  11. Cathepsin B in antigen-presenting cells controls mediators of the Th1 immune response during Leishmania major infection.

    Directory of Open Access Journals (Sweden)

    Iris J Gonzalez-Leal

    2014-09-01

    Full Text Available Resistance and susceptibility to Leishmania major infection in the murine model is determined by the capacity of the host to mount either a protective Th1 response or a Th2 response associated with disease progression. Previous reports involving the use of cysteine cathepsin inhibitors indicated that cathepsins B (Ctsb and L (Ctsl play important roles in Th1/Th2 polarization during L. major infection in both susceptible and resistant mouse strains. Although it was hypothesized that these effects are a consequence of differential patterns of antigen processing, the mechanisms underlying these differences were not further investigated. Given the pivotal roles that dendritic cells and macrophages play during Leishmania infection, we generated bone-marrow derived dendritic cells (BMDC and macrophages (BMM from Ctsb-/- and Ctsl-/- mice, and studied the effects of Ctsb and Ctsl deficiency on the survival of L. major in infected cells. Furthermore, the signals used by dendritic cells to instruct Th cell polarization were addressed: the expression of MHC class II and co-stimulatory molecules, and cytokine production. We found that Ctsb-/- BMDC express higher levels of MHC class II molecules than wild-type (WT and Ctsl-/- BMDC, while there were no significant differences in the expression of co-stimulatory molecules between cathepsin-deficient and WT cells. Moreover, both BMDC and BMM from Ctsb-/- mice significantly up-regulated the levels of interleukin 12 (IL-12 expression, a key Th1-inducing cytokine. These findings indicate that Ctsb-/- BMDC display more pro-Th1 properties than their WT and Ctsl-/- counterparts, and therefore suggest that Ctsb down-regulates the Th1 response to L. major. Moreover, they propose a novel role for Ctsb as a regulator of cytokine expression.

  12. Contribution of enhanced engagement of antigen presentation machinery to the clinical immunogenicity of a human interleukin (IL)-21 receptor-blocking therapeutic antibody.

    Science.gov (United States)

    Xue, L; Hickling, T; Song, R; Nowak, J; Rup, B

    2016-01-01

    Reliable risk assessment for biotherapeutics requires accurate evaluation of risk factors associated with immunogenicity. Immunogenicity risk assessment tools were developed and applied to investigate the immunogenicity of a fully human therapeutic monoclonal antibody, ATR-107 [anti-interleukin (IL)-21 receptor] that elicited anti-drug antibodies (ADA) in 76% of healthy subjects in a Phase 1 study. Because the ATR-107 target is expressed on dendritic cells (DCs), the immunogenicity risk related to engagement with DC and antigen presentation pathways was studied. Despite the presence of IL-21R on DCs, ATR-107 did not bind to the DCs more extensively than the control therapeutic antibody (PF-1) that had elicited low clinical ADA incidence. However, ATR-107, but not the control therapeutic antibody, was translocated to the DC late endosomes, co-localized with intracellular antigen-D related (HLA-DR) molecules and presented a dominant T cell epitope overlapping the complementarity determining region 2 (CDR2) of the light chain. ATR-107 induced increased DC activation exemplified by up-regulation of DC surface expression of CD86, CD274 (PD-L1) and CD40, increased expansion of activated DC populations expressing CD86(hi), CD40(hi), CD83(hi), programmed death ligand 1 (PD-L1)(hi), HLA-DR(hi) or CCR7(hi), as well as elevated secretion of tumour necrosis factor (TNF)-α by DCs. DCs exposed to ATR-107 stimulated an autologous T cell proliferative response in human donor cells, in concert with the detection of immunoglobulin (Ig)G-type anti-ATR-107 antibody response in clinical samples. Collectively, the enhanced engagement of antigen presentation machinery by ATR-107 was suggested. The approaches and findings described in this study may be relevant to identifying lower immunogenicity risk targets and therapeutic molecules. PMID:26400440

  13. Asparagine endopeptidase is not essential for class II MHC antigen presentation but is required for processing of cathepsin L in mice.

    Science.gov (United States)

    Maehr, René; Hang, Howard C; Mintern, Justine D; Kim, You-Me; Cuvillier, Armelle; Nishimura, Mikio; Yamada, Kenji; Shirahama-Noda, Kanae; Hara-Nishimura, Ikuko; Ploegh, Hidde L

    2005-06-01

    Class II MHC molecules survey the endocytic compartments of APCs and present antigenic peptides to CD4 T cells. In this context, lysosomal proteases are essential not only for the generation of antigenic peptides but also for proteolysis of the invariant chain to allow the maturation of class II MHC molecules. Recent studies with protease inhibitors have implicated the asparagine endopeptidase (AEP) in class II MHC-restricted Ag presentation. We now report that AEP-deficient mice show no differences in processing of the invariant chain or maturation of class II MHC products compared with wild-type mice. In the absence of AEP, presentation to primary T cells of OVA and myelin oligodendrocyte glycoprotein, two Ags that contain asparagine residues within or in proximity to the relevant epitopes was unimpaired. Cathepsin (Cat) L, a lysosomal cysteine protease essential for the development to CD4 and NK T cells, fails to be processed into its mature two-chain form in AEP-deficient cells. Despite this, the numbers of CD4 and NK T cells are normal, showing that the single-chain form of Cat L is sufficient for its function in vivo. We conclude that AEP is essential for processing of Cat L but not for class II MHC-restricted Ag presentation. PMID:15905550

  14. Effects of low dose X-ray irradiation on antigen presentation and IL-12 secretion in human dendritic cells in vitro

    International Nuclear Information System (INIS)

    Objective: To explore the effects of low dose X-ray irradiation on the ability of antigen presentation and IL-12 secretion in human dendritic cells that had been cultured for different time in vitro. Methods: The human peripheral blood mononuclear cells (PBMC) were collected and differentiated to dendritic cells (DCs) by rhGM-CSF and rhIL-4 treatment in vitro. The DCs were divided into 3 groups, group A: DCs were cultured for 2 d and then irradiated with 0.05, 0.1, 0.2 and 0.5 Gy X-rays; group B: DCs were cultured for 6 d and then irradiated as above; group C:DCs were cultured without irradiation.At 8 d of cell culture, the DCs were applied to activate T cells and CCK-8 was used to detect MLR (mixed lymphocyte reaction), and the antigen presentation ability of DCs was evaluated. MTT assay was also used to test the cell-killing effect of the activated T-cells on A549 cells. IL-12 in the culture medium of DCs was detected by ELISA. Results: After irradiation with 0.2 and 0.5 Gy X-rays, the antigen presentation ability of DCs was decreased in group A (t=2.79 and 3.71, P<0.05), but significantly increased in group B (t=3.60 and 3.11, P<0.05). The ability of the T cell activation was detected and the proliferation of A549 cells was slightly inhibited by the DCs in group A (t=2.89 and 2.91, P<0.05), but was obviously inhibited by the DCs in group B (t=2.91 and 2.82, P<0.05). Meanwhile,the level of IL-12 was dramatically decreased in group A (t=4.44 and 6.93, P<0.05), but was increased in group B (t=3.51 and 4.12, P<0.05). Conclusions: The abilities of antigen presentation and proliferation inhibition of DCs could be down-regulated by low dose (<0.5 Gy) of X-ray irradiation at the early stage of DCs, but was up-regulated at the late stage of DCs culture. (authors)

  15. CD80 and CD86 Differentially Regulate Mechanical Interactions of T-Cells with Antigen-Presenting Dendritic Cells and B-Cells

    OpenAIRE

    Tong Seng Lim; James Kang Hao Goh; Alessandra Mortellaro; Chwee Teck Lim; Hämmerling, Günter J.; Paola Ricciardi-Castagnoli

    2012-01-01

    Functional T-cell responses are initiated by physical interactions between T-cells and antigen-presenting cells (APCs), including dendritic cells (DCs) and B-cells. T-cells are activated more effectively by DCs than by B-cells, but little is known about the key molecular mechanisms that underpin the particular potency of DC in triggering T-cell responses. To better understand the influence of physical intercellular interactions on APC efficacy in activating T-cells, we used single cell force ...

  16. Gene Related to Anergy in Lymphocytes (GRAIL) Expression in CD4+ T Cells Impairs Actin Cytoskeletal Organization during T Cell/Antigen-presenting Cell Interactions*

    OpenAIRE

    Schartner, Jill M.; Simonson, William T; Wernimont, Sarah A.; Nettenstrom, Lauren M.; Huttenlocher, Anna; Seroogy, Christine M.

    2009-01-01

    GRAIL (gene related to anergy in lymphocytes), is an E3 ubiquitin ligase with increased expression in anergic CD4+ T cells. The expression of GRAIL has been shown to be both necessary and sufficient for the induction of T cell (T) anergy. To date, several subsets of anergic T cells have demonstrated altered interactions with antigen-presenting cells (APC) and perturbed TCR-mediated signaling. The role of GRAIL in mediating these aspects of T cell anergy remains unclear. We used flow cytometry...

  17. VEGF-C Promotes Immune Tolerance in B16 Melanomas and Cross-Presentation of Tumor Antigen by Lymph Node Lymphatics

    Directory of Open Access Journals (Sweden)

    Amanda W. Lund

    2012-03-01

    Full Text Available Tumor expression of the lymphangiogenic factor VEGF-C is correlated with metastasis and poor prognosis, and although VEGF-C enhances transport to the draining lymph node (dLN and antigen exposure to the adaptive immune system, its role in tumor immunity remains unexplored. Here, we demonstrate that VEGF-C promotes immune tolerance in murine melanoma. In B16 F10 melanomas expressing a foreign antigen (OVA, VEGF-C protected tumors against preexisting antitumor immunity and promoted local deletion of OVA-specific CD8+ T cells. Naive OVA-specific CD8+ T cells, transferred into tumor-bearing mice, were dysfunctionally activated and apoptotic. Lymphatic endothelial cells (LECs in dLNs cross-presented OVA, and naive LECs scavenge and cross-present OVA in vitro. Cross-presenting LECs drove the proliferation and apoptosis of OVA-specific CD8+ T cells ex vivo. Our findings introduce a tumor-promoting role for lymphatics in the tumor and dLN and suggest that lymphatic endothelium in the local microenvironment may be a target for immunomodulation.

  18. Enhancement in number and function of antigen-presenting cells in the lymphatic tissue of rats after in vivo administration of diphenylhydantoin (DPH).

    Science.gov (United States)

    Petrasch, S; Wacker, H H; Zou, P; Bechtold, D; Brittinger, G

    1989-01-01

    We present a monoclonal IgG1 antibody, KiMy1R, which is specific for macrophages and their derivatives in the lymphatic tissue of the rat, and evaluate the distribution of subsets of mononuclear cells in popliteal and para-aortal lymph nodes of Wistar rats after injection of 50 mg DPH into the hindpads. Compared with resting lymphatic tissue and lymph nodes of animals treated with phenobarbital, DPH induced a significant increase (P less than 0.01) of the proportion of phagocytic cells. Furthermore, the soluble antigen alkaline phosphatase was traced after inoculation into the footpads of rats: in locoregional lymph nodes the percentage (mean 12.8/10(3] and the total number (mean 476 x 10(3) cells/lymph node) of cells with membrane-bound or intracytoplasmic alkaline phosphatase, as detected by a monoclonal anti-alkaline phosphatase antibody, were significantly higher (P less than 0.001) in animals pretreated with DPH than in rats pretreated with phenobarbital (mean 2.1/10(3); 31.2 x 10(3) cells/lymph node) and in untreated animals (mean 1.9/10(3); 4.1 x 10(3) cells/lymph node). If verified in humans, the effect of DPH in enhancing the number and function of macrophages and other antigen-presenting cells may exert favourable effects in patients with impairment of the mononuclear phagocytic system. Images Fig. 1 PMID:2805417

  19. Balancing selection maintains a form of ERAP2 that undergoes nonsense-mediated decay and affects antigen presentation.

    OpenAIRE

    Andrés, Aida M.; Megan Y Dennis; Warren W Kretzschmar; Cannons, Jennifer L.; Shih-Queen Lee-Lin; Belen Hurle; Schwartzberg, Pamela L.; Williamson, Scott H.; Bustamante, Carlos D.; Rasmus Nielsen; Clark, Andrew G.; Green, Eric D.

    2010-01-01

    A remarkable characteristic of the human major histocompatibility complex (MHC) is its extreme genetic diversity, which is maintained by balancing selection. In fact, the MHC complex remains one of the best-known examples of natural selection in humans, with well-established genetic signatures and biological mechanisms for the action of selection. Here, we present genetic and functional evidence that another gene with a fundamental role in MHC class I presentation, endoplasmic reticulum amino...

  20. Balancing selection maintains a form of ERAP2 that undergoes nonsense-mediated decay and affects antigen presentation

    OpenAIRE

    de Andrés, A.; Dennis, M.; Kretzschmar, W; Cannons, J.; Lee-Lin, S.; Hurle, B.; Schwartzberg, P; Williamson, S.; Bustamante, C; Nielsen, R; Clark, A.; Green, E.

    2010-01-01

    A remarkable characteristic of the human major histocompatibility complex (MHC) is its extreme genetic diversity, which is maintained by balancing selection. In fact, the MHC complex remains one of the best-known examples of natural selection in humans, with well-established genetic signatures and biological mechanisms for the action of selection. Here, we present genetic and functional evidence that another gene with a fundamental role in MHC class I presentation, endoplasmic reticulum amino...

  1. Rainbow trout CK9, a CCL25-like ancient chemokine that attracts and regulates B cells and macrophages, the main antigen presenting cells in fish

    Science.gov (United States)

    Aquilino, Carolina; Granja, Aitor G.; Castro, Rosario; Wang, Tiehui; Abos, Beatriz; Parra, David; Secombes, Christopher J.; Tafalla, Carolina

    2016-01-01

    CK9 is a rainbow trout (Oncorhynchus mykiss) CC chemokine phylogenetically related to mammalian CCL25. Although CK9 is known to be transcriptionally regulated in response to inflammation particularly in mucosal tissues, its functionality has never been revealed. In the current work, we have demonstrated that CK9 is chemoattractant for antigen presenting cells (APCs) expressing major histocompatibility complex class II (MHC II) on the cell surface. Among these APCs, CK9 has a strong chemotactic capacity for both B cells (IgM+ and IgT+) and macrophages. Along with its chemotactic capacities, CK9 modulated the MHC II turnover of B lymphocytes and up-regulated the phagocytic capacity of both IgM+ cells and macrophages. Although CK9 had no lymphoproliferative effects, it increased the survival of IgT+ lymphocytes. Furthermore, we have established that the chemoattractant capacity of CK9 is strongly increased after pre-incubation of leukocytes with a T-independent antigen, whereas B cell receptor (BCR) cross-linking strongly abrogated their capacity to migrate to CK9, indicating that CK9 preferentially attracts B cells at the steady state or under BCR-independent stimulation. These results point to CK9 being a key regulator of B lymphocyte trafficking in rainbow trout, able to modulate innate functions of teleost B lymphocytes and macrophages. PMID:27003360

  2. Presentations

    International Nuclear Information System (INIS)

    The presented materials consist of presentations of international workshop which held in Warsaw from 4 to 5 October 2007. Main subject of the meeting was progress in manufacturing as well as research program development for neutron detector which is planned to be placed at GANIL laboratory and will be used in nuclear spectroscopy research

  3. Dendritic Cell Migration and Antigen Presentation Are Coordinated by the Opposing Functions of the Tetraspanins CD82 and CD37.

    Science.gov (United States)

    Jones, Eleanor L; Wee, Janet L; Demaria, Maria C; Blakeley, Jessica; Ho, Po Ki; Vega-Ramos, Javier; Villadangos, Jose A; van Spriel, Annemiek B; Hickey, Michael J; Hämmerling, Günther J; Wright, Mark D

    2016-02-01

    This study supports a new concept where the opposing functions of the tetraspanins CD37 and CD82 may coordinate changes in migration and Ag presentation during dendritic cell (DC) activation. We have previously published that CD37 is downregulated upon monocyte-derived DC activation, promotes migration of both skin and bone marrow-derived dendritic cells (BMDCs), and restrains Ag presentation in splenic and BMDCs. In this article, we show that CD82, the closest phylogenetic relative to CD37, appears to have opposing functions. CD82 is upregulated upon activation of BMDCs and monocyte-derived DCs, restrains migration of skin and BMDCs, supports MHC class II maturation, and promotes stable interactions between T cells and splenic DCs or BMDCs. The underlying mechanism involves the rearrangement of the cytoskeleton via a differential activation of small GTPases. Both CD37(-/-) and CD82(-/-) BMDCs lack cellular projections, but where CD37(-/-) BMDCs spread poorly on fibronectin, CD82(-/-) BMDCs are large and spread to a greater extent than wild-type BMDCs. At the molecular level, CD82 is a negative regulator of RhoA, whereas CD37 promotes activation of Rac-1; both tetraspanins negatively regulate Cdc42. Thus, this study identifies a key aspect of DC biology: an unactivated BMDC is CD37(hi)CD82(lo), resulting in a highly motile cell with a limited ability to activate naive T cells. By contrast, a late activated BMDC is CD37(lo)CD82(hi), and thus has modified its migratory, cytoskeletal, and Ag presentation machinery to become a cell superbly adapted to activating naive T cells. PMID:26729805

  4. 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...

  5. Human sunlight-induced basal-cell-carcinoma-associated dendritic cells are deficient in T cell co-stimulatory molecules and are impaired as antigen-presenting cells.

    Science.gov (United States)

    Nestle, F O; Burg, G; Fäh, J; Wrone-Smith, T; Nickoloff, B J

    1997-02-01

    Immune surveillance of skin cancer involves the stimulation of effector T cells by tumor-derived antigens and antigen-presenting cells (APCs). An effective APC must not only display processed antigen in the context of MHC molecules but also express co-stimulatory molecules that are required to fully activate T cells. One of the most common cutaneous neoplasms is basal cell carcinoma. To investigate expression of the co-stimulatory molecules CD80 (B7-1) and CD86 (B7-2) on tumor-associated dendritic cells (TADCs), cryosections from basal cell carcinomas were immunostained. In basal cell carcinomas, only 1 to 2% of intratumor and 5 to 10% of peritumor APCs expressed CD80 or CD86. In contrast, biopsies of immunological/inflammatory dermatoses revealed that 38 to 73% of APCs expressed CD80 and CD86. To further evaluate their phenotype and function, TADCs were isolated from tissue samples of basal cell carcinomas; they were non-adherent to plastic, displayed a typical dendritic morphology, and expressed high levels of major histocompatibility class II molecules on their surface. When TADCs were compared with dendritic cells from blood for presentation of superantigens (staphylococcal enterotoxins A and B) to resting autologous T cells, TADCs were consistently weaker stimulators of T cell proliferation than blood dendritic cells. When analyzed by flow cytometry, TADCs expressed high levels of HLA-DR, but only 5 to 10% co-expressed CD80 or CD86. A 3-day culture in granulocyte/macrophage colony-stimulating factor-containing medium partially reconstituted the TADC expression of CD80 and CD86 as well as their immunostimulatory capacity. Thus, in this common skin cancer, although there are prominent collections of HLA-DR-positive APCs in and around tumor cells, the TADCs are deficient in important co-stimulatory molecules as well as being weak stimulators of T cell proliferation. The paucity of co-stimulatory molecule expression and functional activity of TADCs may explain why

  6. PD-L1-deficient mice show that PD-L1 on T cells, antigen-presenting cells, and host tissues negatively regulates T cells

    OpenAIRE

    Latchman, Yvette E.; Liang, Spencer C.; Wu, Yin; Chernova, Tatyana; Sobel, Raymond A.; Klemm, Martina; Kuchroo, Vijay K.; Freeman, Gordon J; Sharpe, Arlene H.

    2004-01-01

    Both positive and negative regulatory roles have been suggested for the B7 family member PD-L1(B7-H1). PD-L1 is expressed on antigen-presenting cells (APCs), activated T cells, and a variety of tissues, but the functional significance of PD-L1 on each cell type is not yet clear. To dissect the functions of PD-L1 in vivo, we generated PD-L1-deficient (PD-L1–/–) mice. CD4+ and CD8+ T cell responses were markedly enhanced in PD-L1–/– mice compared with wild-type mice in vitro and in vivo. PD-L1–...

  7. A Brucella spp. Protease Inhibitor Limits Antigen Lysosomal Proteolysis, Increases Cross-Presentation, and Enhances CD8+ T Cell Responses.

    Science.gov (United States)

    Coria, Lorena M; Ibañez, Andrés E; Tkach, Mercedes; Sabbione, Florencia; Bruno, Laura; Carabajal, Marianela V; Berguer, Paula M; Barrionuevo, Paula; Schillaci, Roxana; Trevani, Analía S; Giambartolomei, Guillermo H; Pasquevich, Karina A; Cassataro, Juliana

    2016-05-15

    In this study, we demonstrate that the unlipidated (U) outer membrane protein (Omp) 19 from Brucella spp. is a competitive inhibitor of human cathepsin L. U-Omp19 inhibits lysosome cathepsins and APC-derived microsome activity in vitro and partially inhibits lysosomal cathepsin L activity within live APCs. Codelivery of U-Omp19 with the Ag can reduce intracellular Ag digestion and increases Ag half-life in dendritic cells (DCs). U-Omp19 retains the Ag in Lamp-2(+) compartments after its internalization and promotes a sustained expression of MHC class I/peptide complexes in the cell surface of DCs. Consequently, U-Omp19 enhances Ag cross-presentation by DCs to CD8(+) T cells. U-Omp19 s.c. delivery induces the recruitment of CD11c(+)CD8α(+) DCs and monocytes to lymph nodes whereas it partially limits in vivo Ag proteolysis inside DCs. Accordingly, this protein is able to induce CD8(+) T cell responses in vivo against codelivered Ag. Antitumor responses were elicited after U-Omp19 coadministration, increasing survival of mice in a murine melanoma challenge model. Collectively, these results indicate that a cysteine protease inhibitor from bacterial origin could be a suitable component of vaccine formulations against tumors. PMID:27084100

  8. T-cell brain infiltration and immature antigen-presenting cells in transgenic models of Alzheimer's disease-like cerebral amyloidosis.

    Science.gov (United States)

    Ferretti, M T; Merlini, M; Späni, C; Gericke, C; Schweizer, N; Enzmann, G; Engelhardt, B; Kulic, L; Suter, T; Nitsch, R M

    2016-05-01

    Cerebral beta-amyloidosis, one of the pathological hallmarks of Alzheimer's disease (AD), elicits a well-characterised, microglia-mediated local innate immune response. In contrast, it is not clear whether cells of the adaptive immune system, in particular T-cells, react to cerebral amyloidosis in AD. Even though parenchymal T-cells have been described in post-mortem brains of AD patients, it is not known whether infiltrating T-cells are specifically recruited to the extracellular deposits of beta-amyloid, and whether they are locally activated into proliferating, effector cells upon interaction with antigen-presenting cells (APCs). To address these issues we have analysed by confocal microscopy and flow-cytometry the localisation and activation status of both T-cells and APCs in transgenic (tg) mice models of AD-like cerebral amyloidosis. Increased numbers of infiltrating T-cells were found in amyloid-burdened brain regions of tg mice, with concomitant up-regulation of endothelial adhesion molecules ICAM-1 and VCAM-1, compared to non-tg littermates. The infiltrating T-cells in tg brains did not co-localise with amyloid plaques, produced less interferon-gamma than those in controls and did not proliferate locally. Bona-fide dendritic cells were virtually absent from the brain parenchyma of both non-tg and tg mice, and APCs from tg brains showed an immature phenotype, with accumulation of MHC-II in intracellular compartments. These results indicate that cerebral amyloidosis promotes T-cell infiltration but interferes with local antigen presentation and T-cell activation. The inability of the brain immune surveillance to orchestrate a protective immune response to amyloid-beta peptide might contribute to the accumulation of amyloid in the progression of the disease. PMID:26872418

  9. Presentations

    International Nuclear Information System (INIS)

    The PARIS meeting held in Cracow, Poland from 14 to 15 May 2007. The main subjects discussed during this meeting were the status of international project dedicated to gamma spectroscopy research. The scientific research program includes investigations of giant dipole resonance, probe of hot nuclei induced in heavy reactions, Jacobi shape transitions, isospin mixing and nuclear multifragmentation. The mentioned programme needs Rand D development such as new scintillations materials as lanthanum chlorides and bromides as well as new photo detection sensors as avalanche photodiodes - such subjects are also subjects of discussion. Additionally results of computerized simulations of scintillation detectors properties by means of GEANT- 4 code are presented

  10. Presentation

    OpenAIRE

    Eduardo Vicente; Rosana de Lima Soares; Eduardo Victorio Morettin

    2013-01-01

    In the present edition of Significação – Scientific Journal for Audiovisual Culture and in the others to follow something new is brought: the presence of thematic dossiers which are to be organized by invited scholars. The appointed subject for the very first one of them was Radio and the invited scholar, Eduardo Vicente, professor at the Graduate Course in Audiovisual and at the Postgraduate Program in Audiovisual Media and Processes of the School of Communication and Arts of the University ...

  11. Presentation

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Freire Vieira

    2013-12-01

    Full Text Available This dossier focuses on one of the essential debate topics today about the territorial dimension of the new development strategies concerned with the worsening of the global socioecological crisis, that is: the challenges related to the activation and integration in networks of localized agri-food systems. For its composition, some contributions presented and debated during the VI International Conference on Localized Agri-food System - The LAFS facing the opportunities and challenges of the new global context have been gathered. The event took place in the city of Florianópolis, from May 21th to 25th of 2013. The event was promoted by the Federal University of Santa Catarina (UFSC and by the Center for the International Cooperation on Agricultural Research for Development (CIRAD. Besides UFSC and CIRAD, EPAGRI, State University of Santa Catarina (UDESC, as well as research institutes and universities from other states (UFMG, IEA/SP, UFS, UFRGS and Mexican and Argentinian partners from the RED SIAL Latino Americana also participated in the organization of lectures, discussion tables and workshops.

  12. CD80 and CD86 differentially regulate mechanical interactions of T-cells with antigen-presenting dendritic cells and B-cells.

    Science.gov (United States)

    Lim, Tong Seng; Goh, James Kang Hao; Mortellaro, Alessandra; Lim, Chwee Teck; Hämmerling, Günter J; Ricciardi-Castagnoli, Paola

    2012-01-01

    Functional T-cell responses are initiated by physical interactions between T-cells and antigen-presenting cells (APCs), including dendritic cells (DCs) and B-cells. T-cells are activated more effectively by DCs than by B-cells, but little is known about the key molecular mechanisms that underpin the particular potency of DC in triggering T-cell responses. To better understand the influence of physical intercellular interactions on APC efficacy in activating T-cells, we used single cell force spectroscopy to characterize and compare the mechanical forces of interactions between DC:T-cells and B:T-cells. Following antigen stimulation, intercellular interactions of DC:T-cell conjugates were stronger than B:T-cell interactions. DCs induced higher levels of T-cell calcium mobilization and production of IL-2 and IFNγ than were elicited by B-cells, thus suggesting that tight intercellular contacts are important in providing mechanically stable environment to initiate T-cell activation. Blocking antibodies targeting surface co-stimulatory molecules CD80 or CD86 weakened intercellular interactions and dampen T-cell activation, highlighting the amplificatory roles of CD80/86 in regulating APC:T-cell interactions and T-cell functional activation. The variable strength of mechanical forces between DC:T-cells and B:T-cell interactions were not solely dependent on differential APC expression of CD80/86, since DCs were superior to B-cells in promoting strong interactions with T-cells even when CD80 and CD86 were inhibited. These data provide mechanical insights into the effects of co-stimulatory molecules in regulating APC:T-cell interactions. PMID:23024807

  13. CD80 and CD86 differentially regulate mechanical interactions of T-cells with antigen-presenting dendritic cells and B-cells.

    Directory of Open Access Journals (Sweden)

    Tong Seng Lim

    Full Text Available Functional T-cell responses are initiated by physical interactions between T-cells and antigen-presenting cells (APCs, including dendritic cells (DCs and B-cells. T-cells are activated more effectively by DCs than by B-cells, but little is known about the key molecular mechanisms that underpin the particular potency of DC in triggering T-cell responses. To better understand the influence of physical intercellular interactions on APC efficacy in activating T-cells, we used single cell force spectroscopy to characterize and compare the mechanical forces of interactions between DC:T-cells and B:T-cells. Following antigen stimulation, intercellular interactions of DC:T-cell conjugates were stronger than B:T-cell interactions. DCs induced higher levels of T-cell calcium mobilization and production of IL-2 and IFNγ than were elicited by B-cells, thus suggesting that tight intercellular contacts are important in providing mechanically stable environment to initiate T-cell activation. Blocking antibodies targeting surface co-stimulatory molecules CD80 or CD86 weakened intercellular interactions and dampen T-cell activation, highlighting the amplificatory roles of CD80/86 in regulating APC:T-cell interactions and T-cell functional activation. The variable strength of mechanical forces between DC:T-cells and B:T-cell interactions were not solely dependent on differential APC expression of CD80/86, since DCs were superior to B-cells in promoting strong interactions with T-cells even when CD80 and CD86 were inhibited. These data provide mechanical insights into the effects of co-stimulatory molecules in regulating APC:T-cell interactions.

  14. IRF1 and NF-kB Restore MHC Class I-Restricted Tumor Antigen Processing and Presentation to Cytotoxic T Cells in Aggressive Neuroblastoma

    Science.gov (United States)

    Cifaldi, Loredana; Antonucci, Chiara; Citti, Arianna; Boldrini, Renata; Pezzullo, Marco; Castellano, Aurora; Russo, Vincenzo; van der Bruggen, Pierre; Giacomini, Patrizio; Locatelli, Franco; Fruci, Doriana

    2012-01-01

    Neuroblastoma (NB), the most common solid extracranial cancer of childhood, displays a remarkable low expression of Major Histocompatibility Complex class I (MHC-I) and Antigen Processing Machinery (APM) molecules, including Endoplasmic Reticulum (ER) Aminopeptidases, and poorly presents tumor antigens to Cytotoxic T Lymphocytes (CTL). We have previously shown that this is due to low expression of the transcription factor NF-kB p65. Herein, we show that not only NF-kB p65, but also the Interferon Regulatory Factor 1 (IRF1) and certain APM components are low in a subset of NB cell lines with aggressive features. Whereas single transfection with either IRF1, or NF-kB p65 is ineffective, co-transfection results in strong synergy and substantial reversion of the MHC-I/APM-low phenotype in all NB cell lines tested. Accordingly, linked immunohistochemistry expression patterns between nuclear IRF1 and p65 on the one hand, and MHC-I on the other hand, were observed in vivo. Absence and presence of the three molecules neatly segregated between high-grade and low-grade NB, respectively. Finally, APM reconstitution by double IRF1/p65 transfection rendered a NB cell line susceptible to killing by anti MAGE-A3 CTLs, lytic efficiency comparable to those seen upon IFN-γ treatment. This is the first demonstration that a complex immune escape phenotype can be rescued by reconstitution of a limited number of master regulatory genes. These findings provide molecular insight into defective MHC-I expression in NB cells and provide the rational for T cell-based immunotherapy in NB variants refractory to conventional therapy. PMID:23071666

  15. Presentation

    Directory of Open Access Journals (Sweden)

    Isidor Marí Mayans

    2004-04-01

    Full Text Available As was the case at the conference, "Humanities professions in the knowledge society", the Director of Humanities and Philology Studies at the UOC, Isidor Marí, presents this Dossier, and the subsequent virtual debate, with the aim of gaining useful conclusions, with specific repercussions on the organisation of the degree studies and its professional projection, especially at this time, which requires study plans to be redesigned in line with the Bologna process. In the author's opinion, we can only make the right operative decisions when we are able to understand the transformations taking place in the humanistic culture framed by the knowledge society, and to do so, debate has to be opened in which students, graduates, academics, researchers, professionals and analysts can all take part.In this article, Isidor Marí analyses the tensions and contradictions that arise when attempts are made to relate the concepts of the professional world, Humanities and the knowledge society. Firstly, neither are Humanities a profession nor the study of Humanities seen by students or society to be adaptable to the definition of professional profiles. However, this highlights an important paradox, as the culture economy, (and, thus, occupations in the cultural sector, is growing increasingly throughout western societies. Likewise, in terms of the relationship between Humanities and the knowledge society, the author describes and analyses how there currently coexist voices foreseeing the worst alongside those that see information and communications technologies opening the way for an enormously positive transformation in human civilisation and a new cultural era.

  16. Presentation

    Directory of Open Access Journals (Sweden)

    Eduardo Vicente

    2013-06-01

    Full Text Available In the present edition of Significação – Scientific Journal for Audiovisual Culture and in the others to follow something new is brought: the presence of thematic dossiers which are to be organized by invited scholars. The appointed subject for the very first one of them was Radio and the invited scholar, Eduardo Vicente, professor at the Graduate Course in Audiovisual and at the Postgraduate Program in Audiovisual Media and Processes of the School of Communication and Arts of the University of São Paulo (ECA-USP. Entitled Radio Beyond Borders the dossier gathers six articles and the intention of reuniting works on the perspectives of usage of such media as much as on the new possibilities of aesthetical experimenting being build up for it, especially considering the new digital technologies and technological convergences. It also intends to present works with original theoretical approach and original reflections able to reset the way we look at what is today already a centennial media. Having broadened the meaning of “beyond borders”, four foreign authors were invited to join the dossier. This is the first time they are being published in this country and so, in all cases, the articles where either written or translated into Portuguese.The dossier begins with “Radio is dead…Long live to the sound”, which is the transcription of a thought provoking lecture given by Armand Balsebre (Autonomous University of Barcelona – one of the most influential authors in the world on the Radio study field. It addresses the challenges such media is to face so that it can become “a new sound media, in the context of a new soundscape or sound-sphere, for the new listeners”. Andrew Dubber (Birmingham City University regarding the challenges posed by a Digital Era argues for a theoretical approach in radio studies which can consider a Media Ecology. The author understands the form and discourse of radio as a negotiation of affordances and

  17. Presentation

    Directory of Open Access Journals (Sweden)

    Nicanor Lopes

    2010-11-01

    Full Text Available The Journal Caminhando debuts with a new editorial format: eachmagazine will have a Dossier.In 2010 Christianity celebrated the centenary of Edinburgh. TheWorld Missionary Conference in Edinburgh in 1910 is regarded by manyas missiological watershed in the missionary and ecumenical movement.So the Faculty of Theology of the Methodist Church (FATEO decidedto organize a Wesleyan Week discussing the issue of mission. For anevent of this magnitude FATEO invited the Rev. Dr. Wesley Ariarajah,Methodist pastor and teacher of Sri Lanka with extensive experience inpastoral ministry in local churches and professor of History of Religionsand the New Testament at the Theological College of Lanka, maintainedby the Protestant Churches in Sri Lanka. In 1981 he was invited to jointhe World Council of Churches, where he presided for over ten years theCouncil of Interreligious Dialogue. From 1992 he served as Deputy GeneralSecretary of the WCC.The following texts are not the speeches of the Rev. Dr. WesleyAriarajah, for they will be published separately. Nevertheless, the journaldialogs with the celebrations of the centenary of Edinburgh, parting formthe intriguing theme: "Mission in the 21st century in Brazil". After all, howis it that mission takes place among us in personal, church, and communityactivities?Within the Dossier, as common to the journal, the textos are organizedas follows: Bible, Theology / History and Pastoral Care. Other items thatdo not fit within the Dossier, but, do articulate mission, can be found inthe section Declarations and Documents and Book Reviews.The authors of the Dossier have important considerations in buildinga contemporary missiological concept considering Brazilian reality.Anderson de Oliveira, in the Bible-Section, presents a significantexegeses of Matthew 26.6-13. What does it mean when Jesus is quotedwith the words: "For the poor always ye have with you, but me ye havenot always." Is this declaration challenging the gospels

  18. Evolutionary and functional relationships of B cells from fish and mammals: insights into their novel roles in phagocytosis and presentation of particulate antigen.

    Science.gov (United States)

    Sunyer, J Oriol

    2012-06-01

    been shown that phagocytic B-1 B cells have a potent ability to present particulate antigen to CD4+ T cells. Thus, studies carried out originally on fish B cells have lead to the discovery of new innate and adaptive roles of B cells in mammals. This review will concentrate on the evolutionary and functional relationships of fish and mammalian B cells, focusing mainly on the newly discovered roles of these cells in phagocytosis, intracellular killing and presentation of particulate antigen. PMID:22394174

  19. Evaluation of the ability of N-terminal fragment of lethal factor of Bacillus anthracis for delivery of Mycobacterium T cell antigen ESAT-6 into cytosol of antigen presenting cells to elicit effective cytotoxic T lymphocyte response

    International Nuclear Information System (INIS)

    We report the ability of N-terminal fragment of lethal factor of Bacillus anthracis to deliver genetically fused ESAT-6 (early secretory antigen target), a potent T cell antigen of Mycobacterium tuberculosis, into cytosol to elicit Cytotoxic T lymphocyte (CTL) response. In vitro Th1 cytokines data and CTL assay proved that efficient delivery of LFn.ESAT-6 occurs in cytosol, in the presence of protective antigen (PA), and leads to generation of effective CTL response. Since CTL response is essential for protection against intracellular pathogens and, it is well known that only single T cell epitope or single antigenic protein is not sufficient to elicit protective CTL response due to variation or polymorphism in MHC-I alleles among the individuals, we suggest that as a fusion protein LFn can be used to deliver multiepitopes of T cells or multiproteins which can generate effective CTLs against intracellular pathogens like M. tuberculosis. It can be used to enhance the protective efficacy of BCG vaccine

  20. A group-specific inhibitor of lysosomal cysteine proteinases selectively inhibits both proteolytic degradation and presentation of the antigen dinitrophenyl-poly-L-lysine by guinea pig accessory cells to T cells

    DEFF Research Database (Denmark)

    Buus, S; Werdelin, O

    1986-01-01

    A limited intralysosomal proteolytic degradation is probably a key event in the accessory cell processing of large protein antigens before their presentation to T cells. With the aid of highly specific inhibitors of proteinases, we have examined the role of proteolysis in the presentation of anti...... inhibitor. Another inhibitor, pepstatin A, which selectively blocks aspartic proteinases, did not block the presentation of dinitrophenyl-poly-L-lysine. The results identify cysteine proteinases, probably lysosomal, as one of the groups of enzymes involved in antigen processing....

  1. Human antigen-presenting cells respond differently to gut-derived probiotic bacteria but mediate similar strain-dependent NK and T cell activation.

    Science.gov (United States)

    Fink, Lisbeth N; Zeuthen, Louise H; Ferlazzo, Guido; Frøkiaer, Hanne

    2007-12-01

    The intestinal microbiota is essential for homeostasis of the local and systemic immune system, and particularly strains of lactic acid bacteria and Escherichia coli have been shown to have balancing effects on inflammatory conditions such as allergy and inflammatory bowel disease. However, in vitro assessment of the immunomodulatory effects of distinct strains may depend strongly on the cell type used as a model. To select the most appropriate model for screening of beneficial bacteria in human cells, the response to strains of intestinal bacteria of three types of antigen-presenting cells (APC) was compared; blood myeloid dendritic cells (DC), monocyte-derived DC and monocytes, and the effector response of natural killer cells and naïve T cells was characterized. Maturation induced by gut-derived bacteria differed between APC, with blood DC and monocytes responding with the production of IL-6 and tumour necrosis factor-alpha to bacteria, which elicited mainly IL-10 in monocyte-derived DC. In contrast, comparable IFN-gamma production patterns were found in both natural killer cells and T cells induced by all bacteria-matured APC. An inhibitory effect of certain strains on this IFN-gamma production was also mediated by all types of APC. The most potent responses were induced by monocyte-derived DC, which thus constitute a sensitive screening model. PMID:17903206

  2. Mitomycin C-treated antigen-presenting cells as a tool for control of allograft rejection and autoimmunity: from bench to bedside.

    Science.gov (United States)

    Terness, Peter; Kleist, Christian; Simon, Helmut; Sandra-Petrescu, Flavius; Ehser, Sandra; Chuang, Jing-Jing; Mohr, Elisabeth; Jiga, Lucian; Greil, Johann; Opelz, Gerhard

    2009-07-01

    Cells have been previously used in experimental models for tolerance induction in organ transplantation and autoimmune diseases. One problem with the therapeutic use of cells is standardization of their preparation. We discuss an immunosuppressive strategy relying on cells irreversibly transformed by a chemotherapeutic drug. Dendritic cells (DCs) of transplant donors pretreated with mitomycin C (MMC) strongly prolonged rat heart allograft survival when injected into recipients before transplantation. Likewise, MMC-DCs loaded with myelin basic protein suppressed autoreactive T cells of MS patients in vitro and prevented experimental autoimmune encephalitis in mice. Comprehensive gene microarray analysis identified genes that possibly make up the suppressive phenotype, comprising glucocorticoid leucine zipper, immunoglobulin-like transcript 3, CD80, CD83, CD86, and apoptotic genes. Based on these findings, a hypothetical model of tolerance induction by MMC-treated DCs is delineated. Finally, we describe the first clinical application of MMC-treated monocyte-enriched donor cells in an attempt to control the rejection of a haploidentical stem cell transplant in a sensitized recipient and discuss the pros and cons of using MMC-treated antigen-presenting cells for tolerance induction. Although many questions remain, MMC-treated cells are a promising clinical tool for controlling allograft rejection and deleterious immune responses in autoimmune diseases. PMID:19393276

  3. Runx1 Regulates Myeloid Precursor Differentiation Into Osteoclasts Without Affecting Differentiation Into Antigen Presenting or Phagocytic Cells in Both Males and Females.

    Science.gov (United States)

    Paglia, David N; Yang, Xiaochuan; Kalinowski, Judith; Jastrzebski, Sandra; Drissi, Hicham; Lorenzo, Joseph

    2016-08-01

    Runt-related transcription factor 1 (Runx1), a master regulator of hematopoiesis, is expressed in preosteoclasts. Previously we evaluated the bone phenotype of CD11b-Cre Runx1(fl/fl) mice and demonstrated enhanced osteoclasts and decreased bone mass in males. However, an assessment of the effects of Runx1 deletion in female osteoclast precursors was impossible with this model. Moreover, the role of Runx1 in myeloid cell differentiation into other lineages is unknown. Therefore, we generated LysM-Cre Runx1(fl/fl) mice, which delete Runx1 equally (∼80% deletion) in myeloid precursor cells from both sexes and examined the capacity of these cells to differentiate into osteoclasts and phagocytic and antigen-presenting cells. Both female and male LysM-Cre Runx1(fl/fl) mice had decreased trabecular bone mass (72% decrease in bone volume fraction) and increased osteoclast number (2-3 times) (P nuclear factor-κB ligand to stimulate osteoclast formation and fusion in female and male mice without affecting other myeloid cell fates. In turn, increased osteoclast activity in LysM-Cre Runx1(fl/fl) mice likely contributed to a decrease in bone mass. These dramatic effects were not due to increased osteoclast precursors in the deleted mutants and argue that inhibition of Runx1 in multipotential myeloid precursor cells is important for osteoclast formation and function. PMID:27267711

  4. Nanoparticle-based targeting of vaccine compounds to skin antigen-presenting cells by hair follicles and their transport in mice.

    Science.gov (United States)

    Mahe, Brice; Vogt, Annika; Liard, Christelle; Duffy, Darragh; Abadie, Valérie; Bonduelle, Olivia; Boissonnas, Alexandre; Sterry, Wolfram; Verrier, Bernard; Blume-Peytavi, Ulrike; Combadiere, Behazine

    2009-05-01

    Particle-based drug delivery systems target active compounds to the hair follicle and may result in a better penetration and higher efficiency of compound uptake by skin resident cells. As previously proposed, such delivery systems could be important tools for vaccine delivery. In this study, we investigated the penetration of solid fluorescent 40 or 200 nm polystyrene nanoparticles (NPs) as well as virus particles in murine skin to further investigate the efficacy of transcutaneously (TC) applied particulate vaccine delivery route. We demonstrated that 40 and 200 nm NPs and modified vaccinia Ankara (MVA) expressing the green-fluorescent protein penetrated deeply into hair follicles and were internalized by perifollicular antigen-presenting cells (APCs). Fibered-based confocal microscopy analyses allowed visualizing in vivo particle penetration along the follicular duct, diffusion into the surrounding tissue, uptake by APCs and transport to the draining lymph nodes. The application of small particles, such as ovalbumin coding DNA or MVA, induced both humoral and cellular immune responses. Furthermore, TC applied MVA induced protection against vaccinia virus challenge. Our results strengthen the concept of TC targeting of cutaneous APCs by hair follicles and will contribute to the development of advanced vaccination protocols using NPs or viral vectors. PMID:19052565

  5. Pharmacologic IKK/NF-κB inhibition causes antigen presenting cells to undergo TNFα dependent ROS-mediated programmed cell death

    Science.gov (United States)

    Tilstra, Jeremy S.; Gaddy, Daniel F.; Zhao, Jing; Davé, Shaival H.; Niedernhofer, Laura J.; Plevy, Scott E.; Robbins, Paul D.

    2014-01-01

    Monocyte-derived antigen presenting cells (APC) are central mediators of the innate and adaptive immune response in inflammatory diseases. As such, APC are appropriate targets for therapeutic intervention to ameliorate certain diseases. APC differentiation, activation and functions are regulated by the NF-κB family of transcription factors. Herein, we examined the effect of NF-κB inhibition, via suppression of the IκB Kinase (IKK) complex, on APC function. Murine bone marrow-derived macrophages and dendritic cells (DC), as well as macrophage and DC lines, underwent rapid programmed cell death (PCD) after treatment with several IKK/NF-κB inhibitors through a TNFα-dependent mechanism. PCD was induced proximally by reactive oxygen species (ROS) formation, which causes a loss of mitochondrial membrane potential and activation of a caspase signaling cascade. NF-κB-inhibition-induced PCD of APC may be a key mechanism through which therapeutic targeting of NF-κB reduces inflammatory pathologies.

  6. Endoplasmic reticulum aminopeptidase-1 alleles associated with increased risk of ankylosing spondylitis reduce HLA-B27 mediated presentation of multiple antigens.

    Science.gov (United States)

    Seregin, Sergey S; Rastall, David P W; Evnouchidou, Irini; Aylsworth, Charles F; Quiroga, Dionisia; Kamal, Ram P; Godbehere-Roosa, Sarah; Blum, Christopher F; York, Ian A; Stratikos, Efstratios; Amalfitano, Andrea

    2013-12-01

    Ankylosing spondylitis (AS) is a chronic systemic arthritic disease that leads to significant disability and loss of quality of life in the ∼0.5% of the worldwide human population it affects. There is currently no cure for AS and mechanisms underlying its pathogenesis remain unclear. AS is highly genetic, with over 70% of the genetic risk being associated with the presence of HLA-B27 and endoplasmic reticulum aminopeptidase-1 (ERAP1) alleles. Furthermore, gene-gene interactions between HLA-B27 and ERAP1 AS risk alleles have recently been confirmed. Here, we demonstrate that various ERAP1 alleles can differentially mediate surface expression of antigens presented by HLA-B27 on human cells. Specifically, for all peptides tested, we found that an ERAP1 variant containing high AS risk SNPs reduced the amount of the peptide presented by HLA-B27, relative to low AS risk ERAP1 variants. These results were further validated using peptide catalysis assays in vitro, suggesting that high AS risk alleles have an enhanced catalytic activity that more rapidly destroys many HLA-B27-destined peptides, a result that correlated with decreased HLA-B27 presentation of the same peptides. These findings suggest that one mechanism underlying AS pathogenesis may involve an altered ability for AS patients harboring both HLA-B27 and high AS risk ERAP1 alleles to correctly display a variety of peptides to the adaptive arm of the immune system, potentially exposing such individuals to higher AS risk due to abnormal display of pathogen or self-derived peptides by the adaptive immune system. PMID:24028501

  7. Cross-Presentation of the Oncofetal Tumor Antigen 5T4 from Irradiated Prostate Cancer Cells--A Key Role for Heat-Shock Protein 70 and Receptor CD91.

    Science.gov (United States)

    Salimu, Josephine; Spary, Lisa K; Al-Taei, Saly; Clayton, Aled; Mason, Malcolm D; Staffurth, John; Tabi, Zsuzsanna

    2015-06-01

    Immune responses contribute to the success of radiotherapy of solid tumors; however, the mechanism of triggering CD8(+) T-cell responses is poorly understood. Antigen cross-presentation from tumor cells by dendritic cells (DC) is a likely dominant mechanism to achieve CD8(+) T-cell stimulation. We established a cross-presentation model in which DCs present a naturally expressed oncofetal tumor antigen (5T4) from irradiated DU145 prostate cancer cells to 5T4-specific T cells. The aim was to establish which immunogenic signals are important in radiation-induced cross-presentation. Radiation (12 Gy) caused G2-M cell-cycle arrest and cell death, increased cellular 5T4 levels, high-mobility protein group-B1 (HMGB1) release, and surface calreticulin and heat-shock protein-70 (Hsp70) expression in DU145 cells. DCs phagocytosed irradiated tumor cells efficiently, followed by upregulation of CD86 on phagocytic DCs. CD8(+) 5T4-specific T cells, stimulated with these DCs, proliferated and produced IFNγ. Inhibition of HMGB1 or the TRIF/MyD88 pathway only had a partial effect on T-cell stimulation. Unlike previous investigators, we found no evidence that DCs carrying Asp299Gly Toll-like receptor-4 (TLR4) single-nucleotide polymorphism had impaired ability to cross-present tumor antigen. However, pretreatment of tumor cells with Hsp70 inhibitors resulted in a highly statistically significant and robust prevention of antigen cross-presentation and CD86 upregulation on DCs cocultured with irradiated tumor cells. Blocking the Hsp70 receptor CD91 also abolished cross-presentation. Together, the results from our study demonstrate that irradiation induces immunologically relevant changes in tumor cells, which can trigger CD8(+) T-cell responses via a predominantly Hsp70-dependent antigen cross-presentation process. PMID:25678582

  8. Expression of Scavenger receptor A on antigen presenting cells is important for CD4+ T-cells proliferation in EAE mouse model

    Directory of Open Access Journals (Sweden)

    Levy-Barazany Hilit

    2012-06-01

    Full Text Available Abstract Background Multiple sclerosis (MS is an autoimmune disease of the central nervous system (CNS characterized by damage to the neuronal myelin sheath. One of the key effectors for inflammatory injury is the antigen-presenting cell (APC. The class A scavenger receptor (SRA, constitutively expressed by APCs, such as macrophages and dendritic cells in peripheral tissues and the CNS, was shown to play a role in the phagocytosis of myelin; however, the role of SRA in the development of experimental autoimmune encephalomyelitis (EAE and autoimmune reaction in the periphery has not yet been studied. Methods We investigated EAE progression in wild-type (WT vs. SRA−/− mice using clinical score measurements and characterized CNS pathology using staining. Furthermore, we assessed SRA role in mediating anti myelin pro-inflammatory response in cell cultures. Results We discovered that EAE progression and CNS demyelination were significantly reduced in SRA−/− mice compared to WT mice. In addition, there was a reduction of infiltrating peripheral immune cells, such as T cells and macrophages, in the CNS lesion of SRA−/− mice, which was associated with reduced astrogliosis. Immunological assessment showed that SRA deficiency resulted in significant reduction of pro-inflammatory cytokines that play a major role in EAE progression, such as IL-2, IFN-gamma, IL-17 and IL-6. Furthermore, we discovered that SRA−/− APCs showed impairments in activation and in their ability to induce pro-inflammatory CD4+ T cell proliferation. Conclusion Expression of SRA on APCs is important for CD4+ T-cells proliferation in EAE mouse model. Further studies of SRA-mediated cellular pathways in APCs may offer useful insights into the development of MS and other autoimmune diseases, providing future avenues for therapeutic intervention.

  9. The ESAT-6 protein of Mycobacterium tuberculosis interacts with beta-2-microglobulin (β2M affecting antigen presentation function of macrophage.

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    Gopalkrishna Sreejit

    2014-10-01

    Full Text Available ESAT-6, an abundantly secreted protein of Mycobacterium tuberculosis (M. tuberculosis is an important virulence factor, inactivation of which leads to reduced virulence of M. tuberculosis. ESAT-6 alone, or in complex with its chaperone CFP-10 (ESAT-6:CFP-10, is known to modulate host immune responses; however, the detailed mechanisms are not well understood. The structure of ESAT-6 or ESAT-6:CFP-10 complex does not suggest presence of enzymatic or DNA-binding activities. Therefore, we hypothesized that the crucial role played by ESAT-6 in the virulence of mycobacteria could be due to its interaction with some host cellular factors. Using a yeast two-hybrid screening, we identified that ESAT-6 interacts with the host protein beta-2-microglobulin (β2M, which was further confirmed by other assays, like GST pull down, co-immunoprecipitation and surface plasmon resonance. The C-terminal six amino acid residues (90-95 of ESAT-6 were found to be essential for this interaction. ESAT-6, in complex with CFP-10, also interacts with β2M. We found that ESAT-6/ESAT-6:CFP-10 can enter into the endoplasmic reticulum where it sequesters β2M to inhibit cell surface expression of MHC-I-β2M complexes, resulting in downregulation of class I-mediated antigen presentation. Interestingly, the ESAT-6:β2M complex could be detected in pleural biopsies of individuals suffering from pleural tuberculosis. Our data highlight a novel mechanism by which M. tuberculosis may undermine the host adaptive immune responses to establish a successful infection. Identification of such novel interactions may help us in designing small molecule inhibitors as well as effective vaccine design against tuberculosis.

  10. Increase in a distinct pulmonary macrophage subset possessing an antigen-presenting cell phenotype and in vitro APC activity following silica exposure

    International Nuclear Information System (INIS)

    Silica inhalation results in chronic lung inflammation and fibrosis. While the role of the alveolar macrophage (AM) is considered key to the effects of silica on lung pathology, the etiology is not completely understood. Evidence suggests an increase in antigen presenting cell (APC) activity as a contributing factor to this process, as well as potential roles for both AM and interstitial macrophages (IM) in silicosis. In order to study the effects of crystalline silica on the APC activity of pulmonary macrophages, mice were exposed intranasally and changes in pulmonary macrophage populations were assessed using flow cytometry. Following intranasal instillation of silica, a significant increase in the APC activity of AM was observed, as well as a significant increase in a subset of IM expressing classic APC markers (MHC class II, CD11c). In addition, an in vitro system using bone marrow-derived macrophages (BMDM) was generated to assess the effects of silica on the APC activity of macrophages in vitro. Data using BMDM in the in vitro APC assay demonstrated a significant increase in APC activity following silica exposure, but not following exposure to saline or a control particle (TiO2). Using a combination of in vivo and in vitro experiments, the current study describes a significant increase in an interstitial macrophage subset with an APC phenotype, as well as an increase in the APC activity of both AM and BMDM, as a direct result of exposure to crystalline silica. These studies suggest a specific mechanism, macrophage subset activation, by which crystalline silica exposure results in chronic pulmonary inflammation and, eventually, fibrosis

  11. Stool Test: H. Pylori Antigen

    Science.gov (United States)

    ... All About Food Allergies Stool Test: H. Pylori Antigen KidsHealth > For Parents > Stool Test: H. Pylori Antigen Print A A A Text Size What's in ... sample is used to determine if H. pylori antigens are present in your child's gastrointestinal (GI) system. ...

  12. Differential Impact of PD-1 and/or Interleukin-10 Blockade on HIV-1-Specific CD4 T Cell and Antigen-Presenting Cell Functions

    Science.gov (United States)

    Porichis, Filippos; Hart, Meghan G.; Zupkosky, Jennifer; Barblu, Lucie; Kwon, Douglas S.; McMullen, Ashley; Brennan, Thomas; Ahmed, Rafi; Freeman, Gordon J.; Kavanagh, Daniel G.

    2014-01-01

    that a population of white blood cells called CD4 T cells that targets the virus fails to work properly. At least part of this impairment is under the control of inhibitory mechanisms that can be blocked to improve the function of these CD4 T cells. In this report, we show that blocking one or two of the molecules involved, called PD-1 and IL-10, has different effects on the individual functions of these cells and that one is strongly improved. We investigate how these effects are caused by interactions between CD4 T cells and antigen-presenting cells. These observations can have implications for new therapeutic approaches in HIV infection. PMID:24352453

  13. Candida soluble cell wall β-glucan facilitates ovalbumin-induced allergic airway inflammation in mice: Possible role of antigen-presenting cells

    Directory of Open Access Journals (Sweden)

    Tamura Hiroshi

    2009-07-01

    Full Text Available Abstract Background Although fungi have been implicated as initiating/deteriorating factors for allergic asthma, their contributing components have not been fully elucidated. We previously isolated soluble β-glucan from Candida albicans (CSBG (Ohno et al., 2007. In the present study, the effects of CSBG exposure on airway immunopathology in the presence or absence of other immunogenic allergen was investigated in vivo, and their cellular mechanisms were analyzed both in vivo and in vitro. Methods In vivo, ICR mice were divided into 4 experimental groups: vehicle, CSBG (25 μg/animal, ovalbumin (OVA: 2 μg/animal, and CSBG + OVA were repeatedly administered intratracheally. The bronchoalveolar lavage cellular profile, lung histology, levels of cytokines and chemokines in the lung homogenates, the expression pattern of antigen-presenting cell (APC-related molecules in the lung digests, and serum immunoglobulin values were studied. In vitro, the impacts of CSBG (0–12.5 μg/ml on the phenotype and function of immune cells such as splenocytes and bone marrow-derived dendritic cells (BMDCs were evaluated in terms of cell proliferation, the surface expression of APC-related molecules, and OVA-mediated T-cell proliferating activity. Results In vivo, repeated pulmonary exposure to CSBG induced neutrophilic airway inflammation in the absence of OVA, and markedly exacerbated OVA-related eosinophilic airway inflammation with mucus metaplasia in mice, which was concomitant with the amplified lung expression of Th2 cytokines and IL-17A and chemokines related to allergic response. Exposure to CSBG plus OVA increased the number of cells bearing MHC class II with or without CD80 in the lung compared to that of others. In vitro, CSBG significantly augmented splenocyte proliferation in the presence or absence of OVA. Further, CSBG increased the expression of APC-related molecules such as CD80, CD86, and DEC205 on BMDCs and amplified OVA-mediated T

  14. Characterization of Yellow Fever Virus Infection of Human and Non-human Primate Antigen Presenting Cells and Their Interaction with CD4+ T Cells.

    Science.gov (United States)

    Cong, Yu; McArthur, Monica A; Cohen, Melanie; Jahrling, Peter B; Janosko, Krisztina B; Josleyn, Nicole; Kang, Kai; Zhang, Tengfei; Holbrook, Michael R

    2016-05-01

    Humans infected with yellow fever virus (YFV), a mosquito-borne flavivirus, can develop illness ranging from a mild febrile disease to hemorrhagic fever and death. The 17D vaccine strain of YFV was developed in the 1930s, has been used continuously since development and has proven very effective. Genetic differences between vaccine and wild-type viruses are few, yet viral or host mechanisms associated with protection or disease are not fully understood. Over the past 20 years, a number of cases of vaccine-associated disease have been identified following vaccination with 17D; these cases have been correlated with reduced immune status at the time of vaccination. Recently, several studies have evaluated T cell responses to vaccination in both humans and non-human primates, but none have evaluated the response to wild-type virus infection. In the studies described here, monocyte-derived macrophages (MDM) and dendritic cells (MoDC) from both humans and rhesus macaques were evaluated for their ability to support infection with either wild-type Asibi virus or the 17D vaccine strain and the host cytokine and chemokine response characterized. Human MoDC and MDM were also evaluated for their ability to stimulate CD4+ T cells. It was found that MoDC and MDM supported viral replication and that there were differential cytokine responses to infection with either wild-type or vaccine viruses. Additionally, MoDCs infected with live 17D virus were able to stimulate IFN-γ and IL-2 production in CD4+ T cells, while cells infected with Asibi virus were not. These data demonstrate that wild-type and vaccine YFV stimulate different responses in target antigen presenting cells and that wild-type YFV can inhibit MoDC activation of CD4+ T cells, a critical component in development of protective immunity. These data provide initial, but critical insight into regulatory capabilities of wild-type YFV in development of disease. PMID:27191161

  15. A Neoglycoconjugate Containing the Human Milk Sugar LNFPIII Drives Anti-Inflammatory Activation of Antigen Presenting Cells in a CD14 Dependent Pathway.

    Directory of Open Access Journals (Sweden)

    Smanla Tundup

    Full Text Available The milk pentasaccharide LNFPIII has therapeutic action for metabolic and autoimmune diseases and prolongs transplant survival in mice when presented as a neoglycoconjugate. Within LNFPIII is the Lewisx trisaccharide, expressed by many helminth parasites. In humans, LNFPIII is found in human milk and also known as stage-specific embryonic antigen-1. LNFPIII-NGC drives alternative activation of macrophages and dendritic cells via NFκB activation in a TLR4 dependent mechanism. However, the connection between LNFPIII-NGC activation of APCs, TLR4 signaling and subsequent MAP kinase signaling leading to anti-inflammatory activation of APCs remains unknown. In this study we determined that the innate receptor CD14 was essential for LNFPIII-NGC induction of both ERK and NFkB activation in APCs. Induction of ERK activation by LNFPIII-NGC was completely dependent on CD14/TLR4-Ras-Raf1/TPL2-MEK axis in bone marrow derived dendritic cells (BMDCs. In addition, LNFPIII-NGC preferentially induced the production of Th2 "favoring" chemokines CCL22 and matrix metalloprotease protein-9 in a CD14 dependent manner in BMDCs. In contrast, LNFPIII-NGC induces significantly lower levels of Th1 "favoring" chemokines, MIP1α, MIP1β and MIP-2 compared to levels in LPS stimulated cells. Interestingly, NGC of the identical human milk sugar LNnT, minus the alpha 1-3 linked fucose, failed to activate APCs via TLR4/MD2/CD14 receptor complex, suggesting that the alpha 1-3 linked fucose in LNFPIII and not on LNnT, is required for this process. Using specific chemical inhibitors of the MAPK pathway, we found that LNFPIII-NGC induction of CCL22, MMP9 and IL-10 production was dependent on ERK activation. Over all, this study suggests that LNFPIII-NGC utilizes CD14/TLR4-MAPK (ERK axis in modulating APC activation to produce anti-inflammatory chemokines and cytokines in a manner distinct from that seen for the pro-inflammatory PAMP LPS. These pathways may explain the in vivo

  16. Differential Impact of PD-1 and/or Interleukin-10 Blockade on HIV-1-Specific CD4 T Cell and Antigen-Presenting Cell Functions

    OpenAIRE

    Porichis, Filippos; Hart, Meghan G.; Zupkosky, Jennifer; Barblu, Lucie; Kwon, Douglas S; McMullen, Ashley; Brennan, Thomas; Ahmed, Rafi; Freeman, Gordon J.; Kavanagh, Daniel G.; Kaufmann, Daniel E.

    2014-01-01

    Antigen persistence in chronic infections and cancer upregulates inhibitory networks, such as the PD-1 and interleukin-10 (IL-10) pathways, that impair immunity and lead to disease progression. These pathways are attractive targets for immunotherapy, as demonstrated by recent clinical trials of PD-1/PD-L1 blockade in cancer patients. However, in HIV-1 infection not all subjects respond to inhibition of either pathway and the mechanistic interactions between these two networks remain to be bet...

  17. Soluble CD14 and CD83 from Human Neonatal Antigen-Presenting Cells Are Inducible by Commensal Bacteria and Suppress Allergen-Induced Human Neonatal Th2 Differentiation▿ †

    OpenAIRE

    Lundell, Anna-Carin; Andersson, Kerstin; Josefsson, Elisabet; Steinkasserer, Alexander; Rudin, Anna

    2007-01-01

    CD14 is expressed on the cell surface of various antigen-presenting cells, and CD83 is a maturation marker for dendritic cells (DC). CD14 and CD83 are also present as soluble proteins, and both have immunoregulatory functions. We examined whether neonatal cord blood monocytes or DC released soluble CD14 (sCD14) or sCD83 when exposed to the commensal intestinal bacteria Clostridium perfringens, Staphylococcus aureus, Lactobacillus rhamnosus, Escherichia coli, and Bacteroides fragilis. We found...

  18. Hepatitis B virus core antigen epitopes presented by HLA-A2 single-chain trimers induce functional epitope-specific CD8+ T-cell responses in HLA-A2.1/Kb transgenic mice.

    Science.gov (United States)

    Zhang, Yuxia; Li, Shu; Shan, Ming; Pan, Xuwen; Zhuang, Ke; He, Lihua; Gould, Keith; Tien, Po

    2007-05-01

    The potency of CD8+ cytotoxic T lymphocyte (CTL) responses toward core antigen has been shown to affect the outcomes of hepatitis B virus (HBV) infection. Since single-chain trimers (SCT) composed of peptide epitope beta2-microglobulin (beta2m) and major histocompatibility complex (MHC) class I heavy chain covalently linked together in a single molecule have been shown to stimulate efficient CTL responses, we investigated the properties of human leucocyte antigen (HLA)-A2 SCTs encoding the HBV core antigen (HBcAg) epitopes C(18-27) and C(107-115). Transfection of NIH-3T3 cells with pcDNA3.0-SCT-C(18-27) and SCT-C(107-115) leads to stable presentation of HBcAg epitopes at the cell surface. HLA-A2.1/Kb transgenic mice vaccinated with the SCT constructs, either as a DNA vaccine alone or followed by a boost with recombinant vaccinia virus, were shown to generate HBcAg-specific CTL responses by enzyme-linked immunospot assay (ELISPOT) and in vitro interferon-gamma release experiments. HBcAg-specific CTLs from vaccinated HLA-A2.1/Kb transgenic mice were able to inhibit HBV surface and e antigen expression as indicated by HepG2.2.15 cells. Our data indicate that a DNA vaccine encoding a human HLA-A2 SCT with HBV epitopes can lead to stable, enhanced HBV core antigen presentation, and may be useful for the control of HBV infection in HLA-A2-positive HBV carriers. PMID:17244158

  19. Alterations in the antigen processing-presenting machinery of transformed plasma cells are associated with reduced recognition by CD8+ T cells and characterize the progression of MGUS to multiple myeloma

    OpenAIRE

    Racanelli, Vito; Leone, Patrizia; Frassanito, Maria Antonia; Brunetti, Claudia; Perosa, Federico; Ferrone, Soldano; Dammacco, Franco

    2010-01-01

    We hypothesized that progression of monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma (MM) reflects the escape of transformed plasma cells from T-cell recognition because of impaired antigen processing-presenting machinery (APM). We studied plasma cells and CD8+ T cells from bone marrow of 20 MGUS patients, 20 MM patients, and 10 control patients. Immunofluorescence and flow cytometry revealed significantly different patterns of APM component expression in plasma c...

  20. Production of CXC and CC chemokines by human antigen-presenting cells in response to Lassa virus or closely related immunogenic viruses, and in cynomolgus monkeys with lassa fever.

    OpenAIRE

    Delphine Pannetier; Stéphanie Reynard; Marion Russier; Xavier Carnec; Sylvain Baize

    2014-01-01

    International audience The pathogenesis of Lassa fever (LF), a hemorrhagic fever endemic to West Africa, remains unclear. We previously compared Lassa virus (LASV) with its genetically close, but nonpathogenic homolog Mopeia virus (MOPV) and demonstrated that the strong activation of antigen-presenting cells (APC), including type I IFN production, observed in response to MOPV probably plays a crucial role in controlling infection. We show here that human macrophages (MP) produce large amou...

  1. Hepatitis B virus induces IL-23 production in antigen presenting cells and causes liver damage via the IL-23/IL-17 axis.

    Directory of Open Access Journals (Sweden)

    Qinghong Wang

    Full Text Available IL-23 regulates myriad processes in the innate and adaptive immune systems, and is a critical mediator of the proinflammatory effects exerted by Th17 cells in many diseases. In this study, we investigated whether and how hepatitis B virus (HBV causes liver damage directly through the IL-23 signaling pathway. In biopsied liver tissues from HBV-infected patients, expression of both IL-23 and IL-23R was remarkably elevated. In vivo observations also indicated that the main sources of IL-23 were myeloid dendritic cells (mDCs and macrophages. Analysis of in vitro differentiated immature DCs and macrophages isolated from healthy donors revealed that the HBV surface antigen (HBsAg efficiently induces IL-23 secretion in a mannose receptor (MR-dependent manner. Culture with an endosomal acidification inhibitor and the dynamin inhibitor showed that, upon binding to the MR, the HBsAg is taken up by mDCs and macrophages through an endocytosis mechanism. In contrast, although the HBV core antigen (HBcAg can also stimulate IL-23 secretion from mDCs, the process was MR- and endocytosis-independent. In addition, IL-23 was shown to be indispensible for HBsAg-stimulated differentiation of naïve CD4(+ T cells into Th17 cells, which were determined to be the primary source of IL-17 in HBV-infected livers. The cognate receptor, IL-17R, was found to exist on the hepatic stellate cells and mDCs, both of which might represent the potential target cells of IL-17 in hepatitis B disease. These data provide novel insights into a yet unrecognized mechanism of HBV-induced hepatitis, by which increases in IL-23 expression, through an MR/endocytosis-dependent or -independent manner, produce liver damage through the IL-23/IL-17 axis.

  2. Interleukin-19: a constituent of the regulome that controls antigen presenting cells in the lungs and airway responses to microbial products.

    Directory of Open Access Journals (Sweden)

    Carol Hoffman

    Full Text Available BACKGROUND: Interleukin (IL-19 has been reported to enhance chronic inflammatory diseases such as asthma but the in vivo mechanism is incompletely understood. Because IL-19 is produced by and regulates cells of the monocyte lineage, our studies focused on in vivo responses of CD11c positive (CD11c+ alveolar macrophages and lung dendritic cells. METHODOLOGY/PRINCIPAL FINDINGS: IL-19-deficient (IL-19-/- mice were studied at baseline (naïve and following intranasal challenge with microbial products, or recombinant cytokines. Naïve IL-19-/- mixed background mice had a decreased percentage of CD11c+ cells in the bronchoalveolar-lavage (BAL due to the deficiency in IL-19 and a trait inherited from the 129-mouse strain. BAL CD11c+ cells from fully backcrossed IL-19-/- BALB/c or C57BL/6 mice expressed significantly less Major Histocompatibility Complex class II (MHCII in response to intranasal administration of lipopolysaccharide, Aspergillus antigen, or IL-13, a pro-allergic cytokine. Neurogenic-locus-notch-homolog-protein-2 (Notch2 expression by lung monocytes, the precursors of BAL CD11c+ cells, was dysregulated: extracellular Notch2 was significantly decreased, transmembrane/intracellular Notch2 was significantly increased in IL-19-/- mice relative to wild type. Instillation of recombinant IL-19 increased extracellular Notch2 expression and dendritic cells cultured from bone marrow cells in the presence of IL-19 showed upregulated extracellular Notch2. The CD205 positive subset among the CD11c+ cells was 3-5-fold decreased in the airways and lungs of naïve IL-19-/- mice relative to wild type. Airway inflammation and histological changes in the lungs were ameliorated in IL-19-/- mice challenged with Aspergillus antigen that induces T lymphocyte-dependent allergic inflammation but not in IL-19-/- mice challenged with lipopolysaccharide or IL-13. CONCLUSIONS/SIGNIFICANCE: Because MHCII is the molecular platform that displays peptides to T

  3. Endogenous antigen presentation by autoantigen-transfected Epstein-Barr virus-lymphoblastoid cells. I. Generation of human thyroid peroxidase-reactive T cells and their T cell receptor repertoire.

    OpenAIRE

    Martin, A; Magnusson, R P; Kendler, D. L.; Concepcion, E; Ben-Nun, A; Davies, T. F.

    1993-01-01

    To develop a model for endogenous thyroid autoantigen presentation, we transfected EBV-transformed B lymphoblastoid cell lines (EBV-LCL), established from patients with autoimmune thyroid disease and normal controls, with cDNA for the human thyroid autoantigen thyroid peroxidase (hTPO). hTPO-antigen presentation to patient peripheral blood T cells was demonstrated after stimulation in vitro for 7 d with irradiated hTPO-transfected or untransfected autologous EBV-LCL. Anti-hTPO-reactive T cell...

  4. Incidental detection of prostate-specific antigen-negative metastatic prostate cancer initially presented with solitary pulmonary nodule on fluorodeoxyglucose positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    A 71-year-old male patient with solitary pulmonary nodule underwent fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) showing slightly increased FDG uptake in this nodule. In addition, PET/CT detected hypermetabolic sclerotic bone lesions in the right second rib and 7th thoracic vertebrae, which were interpreted as possible metastases, and mildly increased FDG uptake in the prostate gland highly suspicious of malignancy. The patient's prostate-specific antigen (PSA) level was within normal range (3.8 ng/dL). The histopathological examination of the lung nodule and right second rib lesion proved metastases from prostate cancer, then the prostate biopsy-confirmed prostate adenocarcinoma. The unique feature of this case is to emphasize the importance of performing PET/CT for solitary pulmonary nodule in detecting PSA-negative metastatic prostate cancer. This case indicated that it should be kept in mind that, even if the PSA is negative, a lung metastasis of prostate cancer may be an underlying cause in patients evaluated for solitary pulmonary nodule by FDG PET/CT

  5. Antigenic presentation of heterologous epitopes engineered into the outer surface-exposed helix 4 loop region of human papillomavirus L1 capsomeres

    Directory of Open Access Journals (Sweden)

    Murata Yoshihiko

    2009-06-01

    Full Text Available Abstract Background Human papillomavirus (HPV L1 capsid proteins can self-assemble into pentamers (capsomeres that are immunogenic and can elicit neutralizing antibodies. Structural modelling of L1 inter-pentameric interactions predicts that helix 4 (h4 of each of the five L1 monomers project laterally and outwards from the pentamer. We sought to utilize HPV L1 capsomeres as a vaccine platform by engineering heterologous epitopes within L1 derivatives deleted for h4 domain. Results We used baculovirus – infected Trichoplusia ni cells and ultracentrifugation to synthesize and purify three 16L1 derivatives: one bearing a short deletion (amino acids 404–436 encompassing the h4 domain, and two others, each bearing a conserved neutralizing epitope of the human respiratory syncytial virus (RSV fusion (F protein (residues 255–278 and 423–436 that was substituted for the deleted L1 h4 domain residues. Each of the three capsomere derivatives was recognized by anti-L1 antibodies, while two bearing the RSV F-derived moieties were recognized by anti-RSV F antibodies. All three L1 derivatives formed ring-like structures that were similar in morphology and size to those described for native 16L1 capsomeres. When injected into mice, each of the capsomere derivatives was immunogenic with respect to L1 protein, and immunization with chimeric L1-RSV F pentamers resulted in RSV non-neutralizing antisera that recognized purified RSV F protein in immunoblots. Conclusion HPV L1 monomers bearing heterologous epitopes within the L1 h4 region can self-assemble into capsomeres that elicit antibody response against such non-HPV encoded epitopes. Thus, the L1 h4 region can function as a novel antigen display site within the L1 pentamer, which in turn may serve as a potential vaccine template.

  6. Galactosylated LDL nanoparticles: a novel targeting delivery system to deliver antigen to macrophages and enhance antigen specific T cell responses

    OpenAIRE

    Wu, Fang; Wuensch, Sherry A.; Azadniv, Mitra; Ebrahimkhani, Mohammad R.; Crispe, I. Nicholas

    2009-01-01

    We aim to define the role of Kupffer cells in intrahepatic antigen presentation, using the selective delivery of antigen to Kupffer cells rather than other populations of liver antigen-presenting cells. To achieve this we developed a novel antigen delivery system that can target antigens to macrophages, based on a galactosylated low-density lipoprotein nano-scale platform. Antigen was delivered via the galactose particle receptor (GPr), internalized, degraded and presented to T cells. The con...

  7. Cancer vaccine--Antigenics.

    Science.gov (United States)

    2002-01-01

    Antigenics is developing a therapeutic cancer vaccine based on heat-shock proteins (HSPs). The vaccine [HSPPC-96, Oncophage] is in a pivotal phase III clinical trial for renal cancer at 80 clinical sites worldwide. The trial is enrolling at least 500 patients who are randomised to receive surgical removal of the primary tumour followed by out-patient treatment with Oncophage((R)) or surgery only. This study was initiated on the basis of results from a pilot phase I/II study and preliminary results from a phase II study in patients with renal cell cancer. In October 2001, Oncophage was designated as a fast-track product by the Food and Drug Administration in the US for the treatment of renal cell carcinoma. Oncophage is in phase I/II trials in Italy for colorectal cancer (30 patients) and melanoma. The trials in Italy are being conducted at the Istituto dei Tumouri, Milan (in association with Sigma-Tau). Preliminary data from the phase II trial for melanoma was presented at the AACR-NCI-EORTC International Conference in Florida, USA, in October 2001. Oncophage is also in a phase I/II (42 patients) and a phase II trial (84 patients) in the US for renal cell cancer, a phase II trial in the US for non-Hodgkin's lymphoma (35 patients), a phase II trial in the US for sarcoma (20-35 patients), a phase I/II trial in the US for melanoma (36 patients), and phase I/II trials in Germany for gastric (30 patients) and pancreatic cancers. A pilot phase I trial in patients with pancreatic cancer began in the US in 1997 with 5 patients enrolled. In November 2000, Antigenics announced that this trial had been expanded to a phase I/II study which would now include survival as an endpoint and would enroll 5 additional patients. The US trials are being performed at Memorial Sloan-Kettering Cancer Center and the M.D. Anderson Cancer Center. The trials in Germany are being carried out at Johannes Gutenberg-University Hospital, Mainz. Oncophage is an autologous vaccine consisting of

  8. Frequent lack of translation of antigen presentation-associated molecules MHC class I, CD1a and Beta(2)-microglobulin in Reed-Sternberg cells

    NARCIS (Netherlands)

    van den Berg, A.; Visser, L; Eberwine, J; Dadvand, L; Poppema, S

    2000-01-01

    Epstein-Barr virus (EBV) is present in Reed-Sternberg (RS) cells of a substantial proportion of Hodgkin's lymphoma cases. Most EBV-positive cases are also MHC class I-positive, whereas the majority of EBV-negative cases lack detectable levels of MHC class I expression. Application of the SAGE techni

  9. The central repeat domain 1 of Kaposi's sarcoma-associated herpesvirus (KSHV) latency associated-nuclear antigen 1 (LANA1) prevents cis MHC class I peptide presentation

    International Nuclear Information System (INIS)

    KSHV LANA1, a latent protein expressed during chronic infection to maintain a viral genome, inhibits major histocompatibility complex class I (MHC I) peptide presentation in cis as a means of immune evasion. Through deletional cloning, we localized this function to the LANA1 central repeat 1 (CR1) subregion. Other CR subregions retard LANA1 translation and proteasomal processing but do not markedly inhibit LANA1 peptide processing by MHC I. Inhibition of proteasomal processing ablates LANA1 peptide presentation. Direct expression of LANA1 within the endoplasmic reticulum (ER) overcomes CR1 inhibition suggesting that CR1 acts prior to translocation of cytoplasmic peptides into the ER. By physically separating CR1 from other subdomains, we show that LANA1 evades MHC I peptide processing by a mechanism distinct from other herpesviruses including Epstein-Barr virus (EBV). Although LANA1 and EBV EBNA1 are functionally similar, they appear to use different mechanisms to evade host cytotoxic T lymphocyte surveillance.

  10. Rapid Antigen Processing and Presentation of a Protective and Immunodominant HLA-B*27-restricted Hepatitis C Virus-specific CD8+ T-cell Epitope

    OpenAIRE

    Julia Schmidt; Iversen, Astrid K N; Stefan Tenzer; Emma Gostick; Price, David A.; Volker Lohmann; Ute Distler; Paul Bowness; Hansjörg Schild; Blum, Hubert E.; Paul Klenerman; Christoph Neumann-Haefelin; Robert Thimme

    2012-01-01

    HLA-B*27 exerts protective effects in hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections. While the immunological and virological features of HLA-B*27-mediated protection are not fully understood, there is growing evidence that the presentation of specific immunodominant HLA-B*27-restricted CD8+ T-cell epitopes contributes to this phenomenon in both infections. Indeed, protection can be linked to single immunodominant CD8+ T-cell epitopes and functional constraints on e...

  11. Review of Mycobacteriumavium subsp. paratuberculosis antigen candidates with diagnostic potential

    DEFF Research Database (Denmark)

    Mikkelsen, Heidi; Aagaard, Claus; Nielsen, Søren Saxmose; Jungersen, Gregers

    development of antibodies and shedding of detectable amounts of MAP. At present, available diagnostic assays are limited by the lack of MAP specific antigens included in these assays resulting in poor specificity. The objective of this review is to provide a systematic overview of diagnostic MAP antigen...... candidates described to date with special emphasis on antigen candidates tested for CMI responses. Relevant information on 115 different MAP antigens was systematically extracted from literature and summarized in 6 tables of CMI antigens, secreted antigens, cell wall and membrane antigens, lipoprotein...... antigens, heat shock antigens and hypothetical antigens. Strategies for evaluation of novel antigen candidates are discussed critically. Relatively few of the described antigens were evaluated for their use in CMI based diagnostic assays and so far, no obvious candidate has been identified for this...

  12. Delivery of Large Heterologous Polypeptides across the Cytoplasmic Membrane of Antigen-Presenting Cells by the Bordetella RTX Hemolysin Moiety Lacking the Adenylyl Cyclase Domain

    Czech Academy of Sciences Publication Activity Database

    Holubová, Jana; Kamanová, Jana; Jelínek, J.; Tomala, Jakub; Mašín, Jiří; Kosová, Martina; Staněk, Ondřej; Bumba, Ladislav; Michálek, J.; Kovář, Marek; Šebo, Peter

    2012-01-01

    Roč. 80, č. 3 (2012), s. 1181-1192. ISSN 0019-9567 R&D Projects: GA AV ČR IAA500200914; GA ČR(CZ) GAP207/11/0717; GA ČR GAP301/11/0325; GA MŠk 1M0506; GA MŠk 2B06161 Institutional research plan: CEZ:AV0Z50200510 Keywords : MHC CLASS-I * ESCHERICHIA-COLI * PRESENTATION PATHWAY Subject RIV: EE - Microbiology, Virology Impact factor: 4.074, year: 2012

  13. Antigen-presenting cells exposed to Lactobacillus acidophilus NCFM, Bifidobacterium bifidum BI-98, and BI-504 reduce regulatory T cell activity

    DEFF Research Database (Denmark)

    Schmidt, Esben Gjerløff Wedebye; Claesson, Mogens Helweg; Jensen, Simon Skjøde;

    2010-01-01

    enteroantigen-presenting cells (APC) and CD4(+)CD25(+) T-regulatory cells (Tregs) in splenocyte-T cell proliferation assays. METHODS:: Splenocytes exposed to enteroantigen +/- probiotics were used to stimulate cultured CD4(+)CD25(-) T cells to which titrated numbers of Tregs were added. Cytokine assays were...... performed by use of neutralizing antibodies and ELISA. RESULTS:: Exposure of APCs to enteroantigens and the series of probiotic strains mentioned above did not influence the stimulatory capacity of APCs on proliferative enteroantigen-specific T cells. However, exposure to B. bifidum BI-98, BI-504 and L....... acidophilus NCFM consistently reduced the suppressive activity of Tregs. The suppressive activity was analyzed using fractionated components of the probiotics, and showed that a component of the cell wall is responsible for the decreased Treg activity in the system. The probiotic-induced suppression of Treg...

  14. Calcitonin Gene-Related Peptide-Exposed Endothelial Cells Bias Antigen Presentation to CD4+ T Cells toward a Th17 Response.

    Science.gov (United States)

    Ding, Wanhong; Stohl, Lori L; Xu, Linghui; Zhou, Xi K; Manni, Michela; Wagner, John A; Granstein, Richard D

    2016-03-01

    Calcitonin gene-related peptide (CGRP) is a neuropeptide with well-established immunomodulatory functions. CGRP-containing nerves innervate dermal blood vessels and lymph nodes. We examined whether CGRP regulates the outcome of Ag presentation by Langerhans cells (LCs) to T cells through actions on microvascular endothelial cells (ECs). Exposure of primary murine dermal microvascular ECs (pDMECs) to CGRP followed by coculture with LCs, responsive CD4(+) T cells and Ag resulted in increased production of IL-6 and IL-17A accompanied by inhibition of IFN-γ, IL-4, and IL-22 compared with wells containing pDMECs treated with medium alone. Physical contact between ECs and LCs or T cells was not required for this effect and, except for IL-4, we demonstrated that IL-6 production by CGRP-treated pDMECs was involved in these effects. CD4(+) cells expressing cytoplasmic IL-17A were increased, whereas cells expressing cytoplasmic IFN-γ or IL-4 were decreased by the presence of CGRP-treated pDMECs. In addition, the level of retinoic acid receptor-related orphan receptor γt mRNA was significantly increased, whereas T-bet and GATA3 expression was inhibited. Immunization at the site of intradermally administered CGRP led to a similar bias in CD4(+) T cells from draining lymph node cells toward IL-17A and away from IFN-γ. Actions of nerve-derived CGRP on ECs may have important regulatory effects on the outcome of Ag presentation with consequences for the expression of inflammatory skin disorders involving Th17 cells. PMID:26829986

  15. African-American (AA) men with local-regional prostate cancer (PC) present with higher prostate specific antigen (PSA) levels than whites: results of RTOG 94-12

    International Nuclear Information System (INIS)

    Purpose/Objective: To use pretreatment serum PSA levels as an20), gleason score (2-5,6-7,7-10), race (whites and AAs), and two interactions viz (a) PSA by race (p=0.0012) and (b) PSA by total gleason score (p=0.0001). When race was replaced by educational status, or income, or both, the fits (0.8246,0.8197, and 0.7815, respectively) were not as good as the fit with race in the model. Conclusion: The findings of this nation-wide prospective registration study with a high percentage of AA patient participation confirms previous, smaller, geographically-limited studies (1,2,3) results that AA patients with non-metastatic PC present with a higher mean PSA values than whites. The multivariate findings imply that, for each level of total gleason score, there is a higher percentage of whites with PSA levels 20. Education and/or income as surrogates of sociological status could not completely explain the racial differences. Other reasons for health-care barriers among AAs need to be identified

  16. Development of tools to target antigen through mannose receptor

    OpenAIRE

    Abbas, Zaigham

    2011-01-01

    Dendritic cells (DC) are unique antigen presenting cells which play a major role in antigen presentation and initiation of the immune response by regulating B- and T- cell activation. Antigen targeting to DC receptors is an effective, safe and specific method for vaccine development. The mannose receptor (MR) is an endocytic receptor expressed by subpopulations of DC and antigen targeting through MR leads to enhanced antigen uptake and presentation to T -cells. This makes MR a favourite recep...

  17. Carcinoma-associated antigens

    International Nuclear Information System (INIS)

    This invention relates to novel antigens associated with breast carcinoma, anti-sera specific to said antigens, 125I-labeled forms of said antigens and methods of detecting said antigens in serum or plasma. The invention also relates to a diagnostic kit containing standardised antigens or antisera or marked forms thereof for the detection of said antigens in human blood, serum or plasma. (author)

  18. Combination of cancer antigen 125 and carcinoembryonic antigen can improve ovarian cancer diagnosis

    DEFF Research Database (Denmark)

    Sørensen, Sofie Sølvsten; Mosgaard, Berit Jul

    2011-01-01

    The purpose of the present study was to evaluate the ability of the tumour marker carcinoembryonic antigen (CEA) in combination with cancer antigen 125 (CA-125) to differentiate between malignant ovarian and malignant non-ovarian disease.......The purpose of the present study was to evaluate the ability of the tumour marker carcinoembryonic antigen (CEA) in combination with cancer antigen 125 (CA-125) to differentiate between malignant ovarian and malignant non-ovarian disease....

  19. 三肽基肽酶Ⅱ(TPPⅡ)对抗原的提呈作用机制研究进展%Progress on mechanism of tripeptidyl-peptidase Ⅱ in the antigenic presentation

    Institute of Scientific and Technical Information of China (English)

    吴玢; 吕凤林; 孔祥军; 任勇刚

    2012-01-01

    Ripetidyl peptidase Ⅱ is a multi-purpose macromolecule serine protease existing in the cytoplasm, which can assists proteasome and other extracellular enzyme participating in the protein metabolism cycle. Recent figures showed that TPP Ⅱ plays a vital contradictory role both in the generation and destroy of MHC- Ⅰ antigen ligands. However, the mechanism involved in these processes remains unclear. In this paper, we first explore the cell biology characteristics of TPP Ⅱ , and then focus on the role of TPPⅡ in the process of MHC - Ⅰ antigen presentation. Finally, we presume that TPP Ⅱ has the important meaning in the new vaccine design.%三肽基肽酶Ⅱ (Ripetidyl PeptidaseⅡ,TPPⅡ)是存在于细胞质中的一种多功能丝氨酸蛋白酶,主要协助蛋白酶体和其他的胞外酶并且参与蛋白周期代谢,最近的数据显示,TPPⅡ对MHC-Ⅰ类分子抗原表位的产生与破坏均有重要作用,但是TPPⅡ在MHC- Ⅰ类抗原递呈中的具体作用机制尚有待进一步研究.本文综述TPPⅡ的细胞生物学特征,着重探究TPPⅡ在MHC- Ⅰ类抗原递呈中作用,并且指出TPPⅡ在新型疫苗设计上具有重要的指导意义.

  20. Antigenic contents of Treponema pallidum preparations.

    OpenAIRE

    Wos, S M; Wicher, K

    1986-01-01

    In investigations of syphilis various Treponema pallidum antigens are used to study the immune responses of naturally or experimentally infected hosts. In the past these antigen preparations have rarely been examined for their antigenic contents and activity. In the present study, supernatant, sediment, and solubilised preparations of T pallidum Nichols strain (20 X 10(9) organisms/ml) and T phagedenis biotype Reiter were examined by modified counterimmunoelectrophoresis and immunoblotting fo...

  1. Carcino-Embryonic Antigen

    International Nuclear Information System (INIS)

    Tumour marker analysis has increased our understanding of the presence of tumours in the body. Carcino-embryonic antigen, CEA, is one of the best studied tumour markers and has proved an ideal diagnostic adjuvant. It has helped in quantifying the amount of disease present in a patient and thence to make accurate prognosis on the various diagnosed ailments. At UCH, it is observed that there is an increase in cancer related ailments and therefore the need for early diagnosis is more compelling in our environment to mitigate future cost of managing advanced manifestation

  2. Histocompatibility antigen test

    Science.gov (United States)

    ... more common in certain autoimmune diseases . For example, HLA-B27 antigen is found in many people (but not ... More Ankylosing spondylitis Autoimmune disorders Bone marrow transplant HLA-B27 antigen Kidney transplant Reactive arthritis Update Date 2/ ...

  3. Production of CXC and CC chemokines by human antigen-presenting cells in response to Lassa virus or closely related immunogenic viruses, and in cynomolgus monkeys with lassa fever.

    Directory of Open Access Journals (Sweden)

    Delphine Pannetier

    Full Text Available The pathogenesis of Lassa fever (LF, a hemorrhagic fever endemic to West Africa, remains unclear. We previously compared Lassa virus (LASV with its genetically close, but nonpathogenic homolog Mopeia virus (MOPV and demonstrated that the strong activation of antigen-presenting cells (APC, including type I IFN production, observed in response to MOPV probably plays a crucial role in controlling infection. We show here that human macrophages (MP produce large amounts of CC and CXC chemokines in response to MOPV infection, whereas dendritic cells (DC release only moderate amounts of CXC chemokines. However, in the presence of autologous T cells, DCs produced CC and CXC chemokines. Chemokines were produced in response to type I IFN synthesis, as the levels of both mediators were strongly correlated and the neutralization of type I IFN resulted in an inhibition of chemokine production. By contrast, LASV induced only low levels of CXCL-10 and CXCL-11 production. These differences in chemokine production may profoundly affect the generation of virus-specific T-cell responses and may therefore contribute to the difference of pathogenicity between these two viruses. In addition, a recombinant LASV (rLASV harboring the NP-D389A/G392A mutations, which abolish the inhibition of type I IFN response by nucleoprotein (NP, induced the massive synthesis of CC and CXC chemokines in both DC and MP, confirming the crucial role of arenavirus NP in immunosuppression and pathogenicity. Finally, we confirmed, using PBMC samples and lymph nodes obtained from LASV-infected cynomolgus monkeys, that LF was associated with high levels of CXC chemokine mRNA synthesis, suggesting that the very early synthesis of these mediators may be correlated with a favourable outcome.

  4. Production of CXC and CC chemokines by human antigen-presenting cells in response to Lassa virus or closely related immunogenic viruses, and in cynomolgus monkeys with lassa fever.

    Science.gov (United States)

    Pannetier, Delphine; Reynard, Stéphanie; Russier, Marion; Carnec, Xavier; Baize, Sylvain

    2014-01-01

    The pathogenesis of Lassa fever (LF), a hemorrhagic fever endemic to West Africa, remains unclear. We previously compared Lassa virus (LASV) with its genetically close, but nonpathogenic homolog Mopeia virus (MOPV) and demonstrated that the strong activation of antigen-presenting cells (APC), including type I IFN production, observed in response to MOPV probably plays a crucial role in controlling infection. We show here that human macrophages (MP) produce large amounts of CC and CXC chemokines in response to MOPV infection, whereas dendritic cells (DC) release only moderate amounts of CXC chemokines. However, in the presence of autologous T cells, DCs produced CC and CXC chemokines. Chemokines were produced in response to type I IFN synthesis, as the levels of both mediators were strongly correlated and the neutralization of type I IFN resulted in an inhibition of chemokine production. By contrast, LASV induced only low levels of CXCL-10 and CXCL-11 production. These differences in chemokine production may profoundly affect the generation of virus-specific T-cell responses and may therefore contribute to the difference of pathogenicity between these two viruses. In addition, a recombinant LASV (rLASV) harboring the NP-D389A/G392A mutations, which abolish the inhibition of type I IFN response by nucleoprotein (NP), induced the massive synthesis of CC and CXC chemokines in both DC and MP, confirming the crucial role of arenavirus NP in immunosuppression and pathogenicity. Finally, we confirmed, using PBMC samples and lymph nodes obtained from LASV-infected cynomolgus monkeys, that LF was associated with high levels of CXC chemokine mRNA synthesis, suggesting that the very early synthesis of these mediators may be correlated with a favourable outcome. PMID:24421914

  5. Production of CXC and CC Chemokines by Human Antigen-Presenting Cells in Response to Lassa Virus or Closely Related Immunogenic Viruses, and in Cynomolgus Monkeys with Lassa Fever

    Science.gov (United States)

    Russier, Marion; Carnec, Xavier; Baize, Sylvain

    2014-01-01

    The pathogenesis of Lassa fever (LF), a hemorrhagic fever endemic to West Africa, remains unclear. We previously compared Lassa virus (LASV) with its genetically close, but nonpathogenic homolog Mopeia virus (MOPV) and demonstrated that the strong activation of antigen-presenting cells (APC), including type I IFN production, observed in response to MOPV probably plays a crucial role in controlling infection. We show here that human macrophages (MP) produce large amounts of CC and CXC chemokines in response to MOPV infection, whereas dendritic cells (DC) release only moderate amounts of CXC chemokines. However, in the presence of autologous T cells, DCs produced CC and CXC chemokines. Chemokines were produced in response to type I IFN synthesis, as the levels of both mediators were strongly correlated and the neutralization of type I IFN resulted in an inhibition of chemokine production. By contrast, LASV induced only low levels of CXCL-10 and CXCL-11 production. These differences in chemokine production may profoundly affect the generation of virus-specific T-cell responses and may therefore contribute to the difference of pathogenicity between these two viruses. In addition, a recombinant LASV (rLASV) harboring the NP-D389A/G392A mutations, which abolish the inhibition of type I IFN response by nucleoprotein (NP), induced the massive synthesis of CC and CXC chemokines in both DC and MP, confirming the crucial role of arenavirus NP in immunosuppression and pathogenicity. Finally, we confirmed, using PBMC samples and lymph nodes obtained from LASV-infected cynomolgus monkeys, that LF was associated with high levels of CXC chemokine mRNA synthesis, suggesting that the very early synthesis of these mediators may be correlated with a favourable outcome. PMID:24421914

  6. Polymorphisms of transporter associated with antigen presentation, tumor necrosis factor-α and interleukin-10 and their implications for protection and susceptibility to severe forms of dengue fever in patients in Sri Lanka

    Directory of Open Access Journals (Sweden)

    Anira N Fernando

    2015-01-01

    Full Text Available Context: To date, a clear understanding of dengue disease pathogenesis remains elusive. Some infected individuals display no symptoms while others develop severe life-threatening forms of the disease. It is widely believed that host genetic factors influence dengue severity. Aims: This study evaluates the relationship between certain polymorphisms and dengue severity in Sri Lankan patients. Settings and Design: Polymorphism studies are carried out on genes for; transporter associated with antigen presentation (TAP, promoter of tumor necrosis factor-α (TNF-α, and promoter of interleukin-10 (IL-10. In other populations, TAP1 (333, TAP2 (379, TNF-α (−308, and IL-10 (−1082, −819, −592 have been associated with dengue and a number of different diseases. Data have not been collected previously for these polymorphisms for dengue patients in Sri Lanka. Materials and Methods: The polymorphisms were typed by amplification refractory mutation system polymerase chain reaction in 107 dengue hemorrhagic fever (DHF patients together with 62 healthy controls. Statistical Analysis Used: Pearson′s Chi-square contingency table analysis with Yates′ correction. Results: Neither the TAP nor the IL-10 polymorphisms considered individually can define dengue disease outcome with regard to severity. However, the genotype combination, IL-10 (−592/−819/−1082 CCA/ATA was significantly associated with development of severe dengue in these patients, suggesting a risk factor to developing DHF. Also, identified is the genotype combination IL-10 (−592/−819/−1082 ATA/ATG which suggested a possibility for protection from DHF. The TNF-α (−308 GG genotype was also significantly associated with severe dengue, suggesting a significant risk factor. Conclusions: The results reported here are specific to the Sri Lankan population. Comparisons with previous reports imply that data may vary from population to population.

  7. Identification of antigenically related polypeptides at centrioles and basal bodies.

    OpenAIRE

    Lin, W.; Fung, B.; Shyamala, M; Kasamatsu, H

    1981-01-01

    An antigen localized at the centriolar region has been identified by indirect immunofluorescence studies in African green monkey kidney, human, hamster, rat, and mouse cells. The antigen consists of two polypeptides of 14,000 and 17,000 daltons. A related antigen is also present at the basal body region in ciliated cells from chicken, cat, mouse, pig, steer, and rabbit trachea and from rabbit fimbria. Immunoelectron microscopy shows that the immunoreactive antigen is indeed located in the reg...

  8. Participation of L3T4 in T cell activation in the absence of class II major histocompatibility complex antigens. Inhibition by anti-L3T4 antibodies is a function both of epitope density and mode of presentation of anti-receptor antibody

    DEFF Research Database (Denmark)

    Owens, T; Fazekas de St Groth, B

    1987-01-01

    activation in the complete absence of class II MHC, immobilized antibody (either Sepharose-coupled or plastic-adsorbed) being more effective. The induction of IL 3 production by suboptimal doses of either Con A or plastic-adsorbed F23.1 was inhibited by the anti-L3T4 antibody GK1.5, as was the response to F...... of T cell/antigen interactions. By using antibodies against the T cell antigen receptor (TCR) to activate T cells, thereby circumventing the requirement for antigen presenting cells and MHC-associated antigen, we have been able to study the function of L3T4 in the absence of class II MHC. We have...... used two monoclonal antibodies, KJ16-133.18 and F23.1, that recognize a determinant encoded by the T cell receptor V beta 8 gene family. These antibodies were used to select two clones of T cells with surface phenotype Thy-1.2+, L3T4+, Lyt-2-, KJ16-133.18+, F23.1+, IA-, IE-. One of these clones (E9.D4...

  9. Antigenic determinants and functional domains in core antigen and e antigen from hepatitis B virus

    International Nuclear Information System (INIS)

    The precore/core gene of hepatitis B virus directs the synthesis of two polypeptides, the 21-kilodalton subunit (p21c) forming the viral nucleocapsid (serologically defined as core antigen [HBcAg]) and a secreted processed protein (p17e, serologically defined as HBe antigen [HBeAg]). Although most of their primary amino acid sequences are identical, HBcAg and HBeAg display different antigenic properties that are widely used in hepatitis B virus diagnosis. To locate and to characterize the corresponding determinants, segments of the core gene were expressed in Escherichia coli and probed with a panel of polyclonal or monoclonal antibodies in radioimmunoassays or enzyme-linked immunosorbent assays, Western blots, and competition assays. Three distinct major determinants were characterized. It is postulated that HBcAg and HBeAg share common basic three-dimensional structure exposing the common linear determinant HBe1 but that they differ in the presentation of two conformational determinants that are either introduced (HBc) or masked (HBe2) in the assembled core. The simultaneous presentation of HBe1 and HBc, two distinctly different antigenic determinants with overlapping amino acid sequences, is interpreted to indicate the presence of slightly differently folded, stable conformational states of p21c in the hepatitis virus nucleocapsid

  10. Binding of recombinant T cell receptor ligands (RTL) to antigen presenting cells prevents upregulation of CD11b and inhibits T cell activation and transfer of experimental autoimmune encephalomyelitis

    OpenAIRE

    Sinha, Sushmita; Miller, Lisa; Subramanian, Sandhya; McCarty, Owen; Proctor, Thomas; Meza-Romero, Roberto; Burrows, Gregory G.; Vandenbark, Arthur A.; Offner, Halina

    2010-01-01

    Recombinant T cell ligands (RTLs) ameliorate experimental autoimmune encephalomyelitis (EAE) in antigen specific manner. We evaluated effects of RTL401 (I-As α1β1 + PLP-139-151) on splenocytes from mice with EAE to study RTL- T cell-tolerance-inducing mechanisms. RTLs bound to B, macrophages and DCs, through RTL-MHC-α1β1 moiety. RTL binding reduced CD11b expression on splenic macrophages/DC, and RTL401-conditioned macrophages/DC, not B cells, inhibited T cell activation. Reduced ability of RT...

  11. Binding of recombinant T cell receptor ligands (RTL) to antigen presenting cells prevents upregulation of CD11b and inhibits T cell activation and transfer of experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Sinha, Sushmita; Miller, Lisa; Subramanian, Sandhya; McCarty, Owen J T; Proctor, Thomas; Meza-Romero, Roberto; Huan, Jianya; Burrows, Gregory G; Vandenbark, Arthur A; Offner, Halina

    2010-08-25

    Recombinant T cell ligands (RTLs) ameliorate experimental autoimmune encephalomyelitis (EAE) in an antigen-specific manner. We evaluated effects of RTL401 (I-A(s) alpha1beta1+PLP-139-151) on splenocytes from SJL/J mice with EAE to study RTL-T cell tolerance-inducing mechanisms. RTLs bound to B, macrophages and DCs, through RTL-MHC-alpha1beta1 moiety. RTL binding reduced CD11b expression on splenic macrophages/DC, and RTL401-conditioned macrophages/DC, not B cells, inhibited T cell activation. Reduced ability of RTL- incubated splenocytes to transfer EAE was likely mediated through macrophages/DC, since B cells were unnecessary for RTL treatment of EAE. These results demonstrate a novel pathway of T cell regulation by RTL-bound APCs. PMID:20546940

  12. Antigen detection for human immunodeficiency virus.

    OpenAIRE

    Harry, D J; Jennings, M B; Yee, J.; Carlson, J. R.

    1989-01-01

    The recent development of enzyme immunoassay procedures for the direct determination of human immunodeficiency virus (HIV) antigens has been of significant benefit in both clinical and research applications. The historical development of HIV antigen assays as well as their current and future applications for use in the clinical microbiology laboratory are reviewed. A detailed description of selected commercially available assays is presented, and a comparison is made of various parameters, in...

  13. Galactosylated LDL nanoparticles: a novel targeting delivery system to deliver antigen to macrophages and enhance antigen specific T cell responses.

    Science.gov (United States)

    Wu, Fang; Wuensch, Sherry A; Azadniv, Mitra; Ebrahimkhani, Mohammad R; Crispe, I Nicholas

    2009-01-01

    We aim to define the role of Kupffer cells in intrahepatic antigen presentation, using the selective delivery of antigen to Kupffer cells rather than other populations of liver antigen-presenting cells. To achieve this we developed a novel antigen delivery system that can target antigens to macrophages, based on a galactosylated low-density lipoprotein nanoscale platform. Antigen was delivered via the galactose particle receptor (GPr), internalized, degraded and presented to T cells. The conjugation of fluoresceinated ovalbumin (FLUO-OVA) and lactobionic acid with LDL resulted in a substantially increased uptake of FLUO-OVA by murine macrophage-like ANA1 cells in preference to NIH3T3 cells, and by primary peritoneal macrophages in preference to primary hepatic stellate cells. Such preferential uptake led to enhanced proliferation of OVA specific T cells, showing that the galactosylated LDL nanoscale platform is a successful antigen carrier, targeting antigen to macrophages but not to all categories of antigen presenting cells. This system will allow targeted delivery of antigen to macrophages in the liver and elsewhere, addressing the question of the role of Kupffer cells in liver immunology. It may also be an effective way of delivering drugs or vaccines directly at macrophages. PMID:19637876

  14. Autoantibodies in autoimmune thyroid disease promote immune complex formation with self antigens and increase B cell and CD4+ T cell proliferation in response to self antigens

    DEFF Research Database (Denmark)

    Nielsen, Claus Henrik; Hegedüs, Laszlo; Leslie, Robert Graham Quinton

    2004-01-01

    B cells are centrally involved as antigen-presenting cells in certain autoimmune diseases. To establish whether autoantibodies form immune complexes (IC) with self-antigens in autoimmune thyroid disease (AITD) and promote B cell uptake of self-antigen, sera from patients with Hashimoto's thyroidi......B cells are centrally involved as antigen-presenting cells in certain autoimmune diseases. To establish whether autoantibodies form immune complexes (IC) with self-antigens in autoimmune thyroid disease (AITD) and promote B cell uptake of self-antigen, sera from patients with Hashimoto...

  15. The distribution of blood group antigens in experimentally produced carcinomas of rat palate

    DEFF Research Database (Denmark)

    Reibel, J; Philipsen, H P; Fisker, A V;

    1986-01-01

    It has been shown previously that rat oral epithelia express antigens cross-reacting with antibodies against human blood group antigen B and its structural precursor, the H antigen (Type 2 chain). In the present study we investigated the expression of these antigens in malignant changes in the rat....... The blood group antigen staining pattern in experimentally produced verrucous carcinomas showed an almost normal blood group antigen expression. This may have diagnostic significance. Localized areas of hyperplastic palatal epithelium with slight dysplasia revealed loss of H antigen and the presence of B...

  16. 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

  17. Antigen smuggling in tuberculosis.

    Science.gov (United States)

    Hudrisier, Denis; Neyrolles, Olivier

    2014-06-11

    The importance of CD4 T lymphocytes in immunity to M. tuberculosis is well established; however, how dendritic cells activate T cells in vivo remains obscure. In this issue of Cell Host & Microbe, Srivastava and Ernst (2014) report a mechanism of antigen transfer for efficient activation of antimycobacterial T cells. PMID:24922567

  18. Antigen detection systems

    Science.gov (United States)

    Infectious agents or their constituent parts (antigens or nucleic acids) can be detected in fresh, frozen, or fixed tissues or other specimens, using a variety of direct or indirect assays. The assays can be modified to yield the greatest sensitivity and specificity but in most cases a particular m...

  19. Aspergillus antigen skin test (image)

    Science.gov (United States)

    The aspergillus antigen skin test determines whether or not a person has been exposed to the mold aspergillus. It is performed by injecting an aspergillus antigen under the skin with a needle. After 48 ...

  20. Tissue distribution of histo-blood group antigens

    DEFF Research Database (Denmark)

    Ravn, V; Dabelsteen, Erik

    2000-01-01

    The introduction of immunohistochemical techniques and monoclonal antibodies to specific carbohydrate epitopes has made it possible to study in detail the tissue distribution of histo-blood group antigens and related carbohydrate structures. The present paper summarizes the available data...... concerning the histological distribution of histo-blood group antigens and their precursor structures in normal human tissues. Studies performed have concentrated on carbohydrate antigens related to the ABO, Lewis, and TTn blood group systems, i.e. histo-blood group antigens carried by type 1, 2, and 3 chain...... carrier carbohydrate chains. Histo-blood group antigens are found in most epithelial tissues. Meanwhile, several factors influence the type, the amount, and the histological distribution of histoblood group antigens, i.e. the ABO, Lewis, and saliva-secretor type of the individual, and the cell- and tissue...

  1. Idiopathic focal segmental glomerulosclerosis and HLA antigens

    Directory of Open Access Journals (Sweden)

    M. Gerbase-DeLima

    1998-03-01

    Full Text Available The objective of the present study was to investigate a possible association between HLA class II antigens and idiopathic focal segmental glomerulosclerosis (FSGS. HLA-A, -B, -DR and -DQ antigens were determined in 19 Brazilian patients (16 white subjects and three subjects of Japanese origin with biopsy-proven FSGS. Comparison of the HLA antigen frequencies between white patients and white local controls showed a significant increase in HLA-DR4 frequency among FSGS patients (37.7 vs 17.2%, P<0.05. In addition, the three patients of Japanese extraction, not included in the statistical analysis, also presented HLA-DR4. In conclusion, our data confirm the association of FSGS with HLA-DR4 previously reported by others, thus providing further evidence for a role of genes of the HLA complex in the susceptibility to this disease

  2. 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...

  3. Antibody-antigen-adjuvant conjugates enable co-delivery of antigen and adjuvant to dendritic cells in cis but only have partial targeting specificity

    NARCIS (Netherlands)

    Kreutz, M.; Giquel, B.; Hu, Q.; Abuknesha, R.; Uematsu, S.; Akira, S.; Nestle, F.O.; Diebold, S.S.

    2012-01-01

    Antibody-antigen conjugates, which promote antigen-presentation by dendritic cells (DC) by means of targeted delivery of antigen to particular DC subsets, represent a powerful vaccination approach. To ensure immunity rather than tolerance induction the co-administration of a suitable adjuvant is par

  4. Immunoassay of antigens

    International Nuclear Information System (INIS)

    A method is described of immunoassay of an antigen in a liquid sample wherein a complex is formed between antigen contained in the said sample and two or more antibody reagents, and the said complex is bound to a solid support by non-covalent bonding as defined herein: and the amount of complex becoming bound to the support is determined; the process employing at least one monoclonal antibody reagent. Labelling methods including radioactive, fluorimetric and enzyme labelling may be used to effect determination of the binding ofthe complex to the solid support. The solid support may take the form of particles, beads, wall-coatings on the reaction vessel or an insert of large surface area. The method is particularly applicable to the assay of TSH, CEA, HCG, alphafeto protein, immunoglobulins, viruses, allergens, bacteria, toxins, drugs and vitamins. Use of monoclonal reagents improves the specificity of the process, and also decreases non-specific binding

  5. Human epidermal Langerhans cells cointernalize by receptor-mediated endocytosis "nonclassical" major histocompatibility complex class I molecules (T6 antigens) and class II molecules (HLA-DR antigens).

    OpenAIRE

    Hanau, D.; Fabre, M.; Schmitt, D A; Garaud, J C; Pauly, G; Tongio, M M; Mayer, S.; Cazenave, J. P.

    1987-01-01

    HLA-DR and T6 surface antigens are expressed only by Langerhans cells and indeterminate cells in normal human epidermis. We have previously demonstrated that T6 antigens are internalized in Langerhans cells and indeterminate cells by receptor-mediated endocytosis. This process is induced by the binding of BL6, a monoclonal antibody directed against T6 antigens. In the present study, using a monoclonal antibody directed against HLA-DR antigens, on human epidermal cells in suspension, we show t...

  6. Engineering of Isogenic Cells Deficient for MR1 with a CRISPR/Cas9 Lentiviral System: Tools To Study Microbial Antigen Processing and Presentation to Human MR1-Restricted T Cells.

    Science.gov (United States)

    Laugel, Bruno; Lloyd, Angharad; Meermeier, Erin W; Crowther, Michael D; Connor, Thomas R; Dolton, Garry; Miles, John J; Burrows, Scott R; Gold, Marielle C; Lewinsohn, David M; Sewell, Andrew K

    2016-08-01

    The nonclassical HLA molecule MHC-related protein 1 (MR1) presents metabolites of the vitamin B synthesis pathways to mucosal-associated invariant T (MAIT) cells and other MR1-restricted T cells. This new class of Ags represents a variation on the classical paradigm of self/non-self discrimination because these T cells are activated through their TCR by small organic compounds generated during microbial vitamin B2 synthesis. Beyond the fundamental significance, the invariant nature of MR1 across the human population is a tantalizing feature for the potential development of universal immune therapeutic and diagnostic tools. However, many aspects of MR1 Ag presentation and MR1-restricted T cell biology remain unknown, and the ubiquitous expression of MR1 across tissues and cell lines can be a confounding factor for experimental purposes. In this study, we report the development of a novel CRISPR/Cas9 genome editing lentiviral system and its use to efficiently disrupt MR1 expression in A459, THP-1, and K562 cell lines. We generated isogenic MR1(-/-) clonal derivatives of the A549 lung carcinoma and THP-1 monocytic cell lines and used these to study T cell responses to intracellular pathogens. We confirmed that MAIT cell clones were unable to respond to MR1(-/-) clones infected with bacteria whereas Ag presentation by classical and other nonclassical HLAs was unaffected. This system represents a robust and efficient method to disrupt the expression of MR1 and should facilitate investigations into the processing and presentation of MR1 Ags as well as into the biology of MAIT cells. PMID:27307560

  7. Studies on vaccine adjuvants to promote CD8+ CTL response through cross-presentation and cross-priming of protein antigens%复合疫苗佐剂促进蛋白抗原通过交叉提呈和交叉致敏诱生CD8+CTL反应的研究

    Institute of Scientific and Technical Information of China (English)

    王美菊; 刘颖; 罗兴; 杨春亭; 于三科; 许洪林

    2012-01-01

    Objective CpG-ODN alone, or in combination with Al(OH)3 or Montanide ISA720, were evaluated for their capacity to promote CD8+ CTL response through cross-presentation and cross-priming of protein antigens. This study would provide implications for the rational design of novel therapeutic vaccines based on protein and peptide antigens. Methods C57BL/6 mice were immunized intramuscularly with chicken ovalbumin (OVA) as a model antigen, alone or in combination with CpG-ODN, Al(0H)3, Montanide ISA720, CpG-ODN + Al(OH)3 or CpG-ODN + Montanide ISA720 as adjuvants, respectively. The protective cellular immune responses were evaluated by intracellular cytokine staining assay, in vivo CTL killing assay, and animal challenge with OVA-expressing melanoma and Listeria monocytogenes. Results Compared with the control group without adjuvant, Al(OH)3 alone was not able to effectively induce cellular immunity. In contrast, CpG-ODN or Montanide ISA720 alone enhanced antigen-specific CD8+ T cell response to some extent, as indicated by IFNγ secretion and CTL activity. However, they were not able to enhance antigen-specific Thl type CD4+ T cell response. Although both composite adjuvants showed stronger adjuvant effects, CpG-ODN + Montanide ISA720 could only enhance IFN7-secreting CD4+ and CD8+ T cell responses, while CpG-ODN + Al(OH)3 enhanced not only IFN7 secreting CD4+ and CD8+ T cell responses but also CD8+ CTL activity. Consistent with this, CpG-ODN + A1(OH)3 as an adjuvant for protein antigen showed promising preventive and therapeutic effects in both melanoma and listeria challenge experiments. Conclusion CpG-ODN + A1(OH)3 as a composite adjuvant can enhance antigen-specific CD8+ CTL response through cross-presentation and cross-priming of protein antigens.%目的 研究CpG寡聚脱氧核苷酸(CpG-oligodeoxynucleotides,CpG-ODN)与Al(OH)3或Montanide ISA720等组成的复合佐剂在小鼠体内促进蛋白抗原通过交叉提呈和交叉致敏诱生CD8+ CTL

  8. Wegener's granulomatosis and autoantibodies to neutrophil antigens

    OpenAIRE

    McCluskey, D R; Maxwell, A. P.; Watt, L

    1988-01-01

    We report five cases of Wegener's granulomatosis all of whom had clinical and histological evidence of disease activity at presentation and in whom autoantibodies to neutrophil antigens were detected. This test may prove useful for the diagnosis of this serious condition and help to monitor disease activity during treatment.

  9. Antigen handling in antigen-induced arthritis in mice: an autoradiographic and immunofluorescence study using whole joint sections

    International Nuclear Information System (INIS)

    Antigen localization after intraarticular antigen injection was studied in immune and nonimmune mice using autoradiographic and immunofluorescence techniques on whole joint sections. After intraarticular injection of radiolabeled methylated bovine serum albumin (125I-mBSA) in immune mice, labeling in the synovium and synovial exudate diminished rapidly, apart from some deposits in fibrinlike material present in the joint cavity. Long-term antigen retention was found in avascular and hypovascular structures lining the joint cavity, albeit not along the whole surface; eg, labeling remained present at the edges of the femoral condyle hyaline cartilage but not at the central weight-bearing region; long-term retention at ligaments was only found at the insertion sites. Immunofluorescence data in immune animals showed antigen retention together with the presence of immunoglobulins and complement, indicating that antigen is retained at least in part in the form of immune complexes. Nonimmune mice showed even higher long-term antigen retention than immune animals, probably related to physico-chemical properties of the antigen enabling nonimmune binding to articular structures, but also indicating that the presence of joint inflammation in the immune animals enhances antigen clearance. Histologic examination of the ligaments and patellar cartilage of immune mice did reveal that long-term antigen retention was not anatomically related to nearby inflammation or to local tissue damage. The importance of long-term antigen retention for the chronicity of arthritis may lie in the leakage of small amounts of this antigen to joint compartments where it does behave as an inflammatory stimulus; it may further be that it renders the joint a specifically hypersensitive area

  10. How to Make a Non-Antigenic Protein (Auto) Antigenic: Molecular Complementarity Alters Antigen Processing and Activates Adaptive-Innate Immunity Synergy.

    Science.gov (United States)

    Root-Bernstein, Robert

    2015-01-01

    Evidence is reviewed that complementary proteins and peptides form complexes with increased antigenicity and/or autoimmunogenicity. Five case studies are highlighted: 1) diphtheria toxin-antitoxin (antibody), which induces immunity to the normally non-antigenic toxin, and autoimmune neuritis; 2) tryptophan peptide of myelin basic protein and muramyl dipeptide ("adjuvant peptide"), which form a complex that induces experimental allergic encephalomyelitis; 3) an insulin and glucagon complex that is far more antigenic than either component individually; 4) various causes of experimental autoimmune myocarditis such as C protein in combination with its antibody, or coxsackie B virus in combination with the coxsackie and adenovirus receptor; 5) influenza A virus haemagglutinin with the outer membrane protein of the Haemophilus influenzae, which increases antigenicity. Several mechanisms cooperate to alter immunogenicity. Complexation alters antigen processing, protecting the components against proteolysis, altering fragmentation and presenting novel antigens to the immune system. Complementary antigens induce complementary adaptive immune responses (complementary antibodies and/or T cell receptors) that produce circulating immune complexes (CIC). CIC stimulate innate immunity. Concurrently, complementary antigens stimulate multiple Toll-like receptors that synergize to over-produce cytokines, which further stimulate adaptive immunity. Thus innate and adaptive immunity form a positive feedback loop. If components of the complex mimic a host protein, then autoimmunity may result. Enhanced antigenicity for production of improved vaccines and/or therapeutic autoimmunity (e.g., against cancer cells) might be achieved by using information from antibody or TCR recognition sites to complement an antigen; by panning for complements in randomized peptide libraries; or using antisense peptide strategies to design complements. PMID:26179268

  11. Human leucocyte antigens in tympanosclerosis.

    Science.gov (United States)

    Dursun, G; Acar, A; Turgay, M; Calgüner, M

    1997-02-01

    This study was designed to evaluate the association between certain HLA antigens and tympanosclerosis. The serum concentrations of HLA antigens were measured by a microlymphocytotoxicity technique in patients with tympanosclerosis and compared with a healthy control group. The serum levels of HLA-B35 and -DR3 were significantly higher in the patients with tympanosclerosis. This result suggests that certain types of HLA antigens may play an important role as an indicator or mediator in the pathogenesis of tympanosclerosis. PMID:9088683

  12. Antigenic variants of rabies virus

    OpenAIRE

    Wiktor, TJ; Koprowski, H

    1980-01-01

    Antigenic variants of CVS-11 strain of rabies virus were selected after treatment of virus populations with monoclonal antibodies directed against the glycoprotein antigen of the virus. These variants resisted neutralization by the hybridoma antibody used for their selection. Two independently mutating antigenic sites could be distinguished when five variants were tested with nine hybridoma antibodies. The frequency of single epitope variants in a cloned rabies virus seed was approximately 1:...

  13. Autophagy proteins stabilize pathogen-containing phagosomes for prolonged MHC II antigen processing.

    Science.gov (United States)

    Romao, Susana; Gasser, Nathalie; Becker, Andrea C; Guhl, Bruno; Bajagic, Milica; Vanoaica, Danusia; Ziegler, Urs; Roesler, Joachim; Dengjel, Jörn; Reichenbach, Janine; Münz, Christian

    2013-12-01

    Antigen preservation for presentation is a hallmark of potent antigen-presenting cells. In this paper, we report that in human macrophages and dendritic cells, a subset of phagosomes gets coated with Atg8/LC3, a component of the molecular machinery of macroautophagy, and maintains phagocytosed antigens for prolonged presentation on major histocompatibility complex class II molecules. These Atg8/LC3-positive phagosomes are formed around the antigen with TLR2 agonists and require reactive oxygen species production by NOX2 for their generation. A deficiency in the NOX2-dependent formation of these antigen storage phagosomes could contribute to compromise antifungal immune control in chronic granulomatous disease patients. PMID:24322427

  14. The global antigenic diversity of swine influenza A viruses

    DEFF Research Database (Denmark)

    Lewis, Nicola S; Russell, Colin A; Langat, Pinky;

    2016-01-01

    Swine influenza presents a substantial disease burden for pig populations worldwide and poses a potential pandemic threat to humans. There is considerable diversity in both H1 and H3 influenza viruses circulating in swine due to the frequent introductions of viruses from humans and birds coupled...... with geographic segregation of global swine populations. Much of this diversity is characterized genetically but the antigenic diversity of these viruses is poorly understood. Critically, the antigenic diversity shapes the risk profile of swine influenza viruses in terms of their epizootic and pandemic...... potential. Here, using the most comprehensive set of swine influenza virus antigenic data compiled to date, we quantify the antigenic diversity of swine influenza viruses on a multi-continental scale. The substantial antigenic diversity of recently circulating viruses in different parts of the world adds...

  15. 9 CFR 113.407 - Pullorum antigen.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Pullorum antigen. 113.407 Section 113... and Reagents § 113.407 Pullorum antigen. Pullorum Antigen shall be produced from a culture of... standard for stained antigen K's and 50 ±10 times McFarland No. 1 standard for tube antigen....

  16. Mouse placental macrophages have a decreased ability to present antigen.

    OpenAIRE

    Chang, M D; Pollard, J W; Khalili, H; Goyert, S M; Diamond, B.

    1993-01-01

    Large numbers of macrophages can be found in an animal's uteroplacental unit. This high concentration of macrophages suggests they must play an important role during placental development. To gain a better understanding of the functional capacity of placental macrophages, we have obtained a highly enriched placental macrophage culture and have derived several cell lines from this population. Both placental macrophages and cell lines show colony-stimulating factor 1-dependent growth, express F...

  17. Antigen antibody interactions

    CERN Document Server

    DeLisi, Charles

    1976-01-01

    1. 1 Organization of the Immune System One of the most important survival mechanisms of vertebrates is their ability to recognize and respond to the onslaught of pathogenic microbes to which they are conti- ously exposed. The collection of host cells and molecules involved in this recognition­ 12 response function constitutes its immune system. In man, it comprises about 10 cells 20 (lymphocytes) and 10 molecules (immunoglobulins). Its ontogenic development is c- strained by the requirement that it be capable of responding to an almost limitless variety of molecular configurations on foreign substances, while simultaneously remaining inert to those on self components. It has thus evolved to discriminate, with exquisite precision, between molecular patterns. The foreign substances which induce a response, called antigens, are typically large molecules such as proteins and polysaccharides. The portions of these with which immunoglobulins interact are called epitopes or determinants. A typical protein epitope m...

  18. Trypanosoma cruzi: circulating antigens

    Directory of Open Access Journals (Sweden)

    V. Bongertz

    1981-03-01

    Full Text Available Circulating antigens were detected in sera of mice experimentally infected with a high close of Trypanosoma cruzi by reaction with sera from chronically infected mice. The immunodiffusion reaction between homologous acute and chronic sera produced four precipitation lines. By reaction with chronic mouse serum, circulating antingens were detected in sera from heavily infected hamsters, dogs, rabbits and in sera from chagasic patients. A reaction was also found in urine from acutely infected mice and dogs. Trypanosoma cruzi exoantigen was detected in trypanosome culture medium and in the supernatant of infected cell cultures. Attempts to isolate the antigens are described.Antígenos circulantes foram detectados em soros de camundongos infectados experimentalmente com elevadas doses de Trypanosoma cruzi pela reação com soros obtidos de camundongos em fase crônica de infecção. A reação de imunodifusão entre soros homólogos agudo e crônico produziu quatro linhas de precipitação. Por reação com soro crônico de camundongo antígenos circulantes foram detectados em soros de crícetos, cães e coelhos infectados com doses elevadas de Trypanosoma cruzi e em soros de pacientes chagásicos. Uma reação foi também observada com urina de camundongos e cães infectados de forma aguda. Exoantígeno de Trypanosoma cruzi foi detectado em meio de cultura de tripanosomas e em sobrenadantes de culturas de células infectadas. Tentativas de isolamento dos antigenos são descritas.

  19. Cancer antigen 125 and prognosis

    DEFF Research Database (Denmark)

    Høgdall, Estrid Vilma Solyom

    2008-01-01

    PURPOSE OF REVIEW: This review addresses recently reported progress in cancer antigen 125 as a prognostic marker in patients with ovarian cancer. RECENT FINDINGS: Serum cancer antigen 125 levels measured preoperatively in both early and late stage ovarian cancer may be of prognostic value. Before...... cancer antigen 125 determination may be implemented into clinical practice, cut-off levels must be evaluated and internationally defined. Studies examining serum cancer antigen 125 levels after surgery but before, during, or after treatment confirmed that changes in serum levels are of prognostic value....... Furthermore, recent studies have shown that the level of expression of cancer antigen 125 in tissue may be an independent prognostic indicator in late stage ovarian cancer. SUMMARY: Prognostic markers may potentially help to individualize treatment within subgroups of patients. In a recent study the level of...

  20. Molecular identification and antigenic characterization of a merozoite surface antigen and a secreted antigen of Babesia canis (BcMSA1 and BcSA1)

    OpenAIRE

    Zhou, Mo; Cao, Shinuo; Luo, Yuzi; Liu, Mingming; Wang, Guanbo; Moumouni, Paul Franck Adjou; Jirapattharasate, Charoonluk; IGUCHI, Aiko; Vudriko, Patrick; Terkawi, Mohamad Alaa; Löwenstein, Mario; Kern, Angela; Nishikawa, Yoshifumi; Suzuki, Hiroshi; Igarashi, Ikuo

    2016-01-01

    Background Babesia canis is an apicomplexan tick-transmitted hemoprotozoan responsible for causing canine babesiosis in Europe and west Asia. Despite its importance, there is no known rapid diagnostic kit detection of B. canis infection in dogs. The present study identified two novel antigens of B. canis and used the recombinant antigens to establish a rapid, specific and sensitive serodiagnostic technique for detection of B. canis infection. Methods A complementary DNA (cDNA) expression libr...

  1. [Antigenic response against PPD and antigen 60 in tubercular patients: single antigen versus the combined test].

    Science.gov (United States)

    Máttar, S; Broquetas, J M; Gea, J; Aran, X; el-Banna, N; Sauleda, J; Torres, J M

    1992-05-01

    We analyze serum samples from 70 patients with pulmonary tuberculosis and 50 healthy individuals. The antigenic activity (IgG) against protein purified antigen (PPD) and antigen 60 (A60) from M. tuberculosis. Thirteen patients were also HIV infected, and three patients had AIDS defined by the presence of disseminated tuberculosis. The test using antigen alone showed a 77% sensitivity and 74% specificity when PPD is used. When A60 was used, both values improved (81% sensitivity, 94% specificity). The use of a combined test (PPD and A60) improves the sensitivity (89%) but reduces the specificity (82%). The HIV infected patients showed similar responses to those of other patients. The combined use of different antigens might be useful for diagnosing tuberculosis. PMID:1390996

  2. COLONOSCOPY AND CARCINOEMBRYONIC ANTIGEN VARIATIONS

    Directory of Open Access Journals (Sweden)

    Rita G SOUSA

    2014-03-01

    Full Text Available Context Colonoscopy is essential for synchronous and metachronous cancer detection. Carcinoembryonic antigen is a colorectal cancer tumor marker, important as a follow-up tool in patients with previous colorectal cancer. False-positive carcinoembryonic antigen elevation results in multiples exams and in patient anxiety. In literature, there is reference to transient carcinoembryonic antigen increase with colonoscopy. Objective To evaluate the influence of bowel preparation and colonoscopy in carcinoembryonic antigen blood levels. Methods We prospectively studied subjects that underwent routine colonoscopy in our institution. Blood samples were collected (1 before bowel cleaning, (2 before colonoscopy and (3 immediately after colonoscopy. Blood carcinoembryonic antigen levels were determined by “Sandwich” immunoassay. The statistical methods used were the paired t-test and ANOVA. Results Thirty-seven patients (22M/15F were included; age range 28-84 (mean 56 years. Mean carcinoembryonic antigen values were 1.9, 2 and 1.8 for (1, (2 and (3, respectively. An increase in value (2 compared with (1 was observed in 20/37 patients (P = 0.018, mainly in younger patients and in patients requiring more endoluminal interventions. In 29/37 patients, the CEA value decreased from (2 to (3 (P = 1.3x10-7. Conclusions A trend for carcinoembryonic antigen increase after bowel cleaning was observed, especially in younger patients and in patients with more endoluminal interventions, but without clinical meaning.

  3. Simple solid-phase radioimmunoassay for human leukemia-associated cell membrane antigens

    International Nuclear Information System (INIS)

    In the present study, a simple solid-phase radioimmunoassay was developed to determine detergent-extracted human leukemia-associated cell membrane antigens. In the assay, 96-well microtiter plates are coated with human leukemia cell membrane antigens containing a T cell leukemia or a non-T cell leukemia antigen in the presence of a detergent, and treated with 1.6% bovine serum albumin solution. The coated antigens were reacted with an appropriate murine monoclonal antibody (mAb). The bound mAb is determined by a second reaction with 125I-labeled F(ab')2 of goat anti-mouse Ig. The best antigen dose-dependent antibody binding results were obtained using the plates coated with antigens in the presence of taurocholate. In addition, the usefulness of the present assay with taurocholate during the purification of the antigens was demonstrated. (Auth.)

  4. Antibody-antigen-adjuvant conjugates enable co-delivery of antigen and adjuvant to dendritic cells in cis but only have partial targeting specificity.

    Directory of Open Access Journals (Sweden)

    Martin Kreutz

    Full Text Available Antibody-antigen conjugates, which promote antigen-presentation by dendritic cells (DC by means of targeted delivery of antigen to particular DC subsets, represent a powerful vaccination approach. To ensure immunity rather than tolerance induction the co-administration of a suitable adjuvant is paramount. However, co-administration of unlinked adjuvant cannot ensure that all cells targeted by the antibody conjugates are appropriately activated. Furthermore, antigen-presenting cells (APC that do not present the desired antigen are equally strongly activated and could prime undesired responses against self-antigens. We, therefore, were interested in exploring targeted co-delivery of antigen and adjuvant in cis in form of antibody-antigen-adjuvant conjugates for the induction of anti-tumour immunity. In this study, we report on the assembly and characterization of conjugates consisting of DEC205-specific antibody, the model antigen ovalbumin (OVA and CpG oligodeoxynucleotides (ODN. We show that such conjugates are more potent at inducing cytotoxic T lymphocyte (CTL responses than control conjugates mixed with soluble CpG. However, our study also reveals that the nucleic acid moiety of such antibody-antigen-adjuvant conjugates alters their binding and uptake and allows delivery of the antigen and the adjuvant to cells partially independently of DEC205. Nevertheless, antibody-antigen-adjuvant conjugates are superior to antibody-free antigen-adjuvant conjugates in priming CTL responses and efficiently induce anti-tumour immunity in the murine B16 pseudo-metastasis model. A better understanding of the role of the antibody moiety is required to inform future conjugate vaccination strategies for efficient induction of anti-tumour responses.

  5. Molecular mimics of the tumour antigen MUC1.

    Directory of Open Access Journals (Sweden)

    Tharappel C James

    Full Text Available A key requirement for the development of cancer immunotherapy is the identification of tumour-associated antigens that are differentially or exclusively expressed on the tumour and recognized by the host immune system. However, immune responses to such antigens are often muted or lacking due to the antigens being recognized as "self", and further complicated by the tumour environment and regulation of immune cells within. In an effort to circumvent the lack of immune responses to tumour antigens, we have devised a strategy to develop potential synthetic immunogens. The strategy, termed mirror image phage display, is based on the concept of molecular mimicry as demonstrated by the idiotype/anti-idiotype paradigm in the immune system. Here as 'proof of principle' we have selected molecular mimics of the well-characterised tumour associated antigen, the human mucin1 protein (MUC1 from two different peptide phage display libraries. The putative mimics were compared in structure and function to that of the native antigen. Our results demonstrate that several of the mimic peptides display T-cell stimulation activity in vitro when presented by matured dendritic cells. The mimic peptides and the native MUC1 antigenic epitopes can cross-stimulate T-cells. The data also indicate that sequence homology and/or chemical properties to the original epitope are not the sole determining factors for the observed immunostimulatory activity of the mimic peptides.

  6. Genetic diversity and antigenicity variation of Babesia bovis merozoite surface antigen-1 (MSA-1) in Thailand.

    Science.gov (United States)

    Tattiyapong, Muncharee; Sivakumar, Thillaiampalam; Takemae, Hitoshi; Simking, Pacharathon; Jittapalapong, Sathaporn; Igarashi, Ikuo; Yokoyama, Naoaki

    2016-07-01

    Babesia bovis, an intraerythrocytic protozoan parasite, causes severe clinical disease in cattle worldwide. The genetic diversity of parasite antigens often results in different immune profiles in infected animals, hindering efforts to develop immune control methodologies against the B. bovis infection. In this study, we analyzed the genetic diversity of the merozoite surface antigen-1 (msa-1) gene using 162 B. bovis-positive blood DNA samples sourced from cattle populations reared in different geographical regions of Thailand. The identity scores shared among 93 msa-1 gene sequences isolated by PCR amplification were 43.5-100%, and the similarity values among the translated amino acid sequences were 42.8-100%. Of 23 total clades detected in our phylogenetic analysis, Thai msa-1 gene sequences occurred in 18 clades; seven among them were composed of sequences exclusively from Thailand. To investigate differential antigenicity of isolated MSA-1 proteins, we expressed and purified eight recombinant MSA-1 (rMSA-1) proteins, including an rMSA-1 from B. bovis Texas (T2Bo) strain and seven rMSA-1 proteins based on the Thai msa-1 sequences. When these antigens were analyzed in a western blot assay, anti-T2Bo cattle serum strongly reacted with the rMSA-1 from T2Bo, as well as with three other rMSA-1 proteins that shared 54.9-68.4% sequence similarity with T2Bo MSA-1. In contrast, no or weak reactivity was observed for the remaining rMSA-1 proteins, which shared low sequence similarity (35.0-39.7%) with T2Bo MSA-1. While demonstrating the high genetic diversity of the B. bovis msa-1 gene in Thailand, the present findings suggest that the genetic diversity results in antigenicity variations among the MSA-1 antigens of B. bovis in Thailand. PMID:27101782

  7. 小剂量X射线照射对人树突状细胞抗原递呈及白介素-12分泌的影响%Effects of low dose X-ray irradiation on antigen presentation and IL-12 secretion in human dendritic cells in vitro

    Institute of Scientific and Technical Information of China (English)

    闫鹏; 江其生; 李峰生; 何蕊; 王翠兰; 李晓

    2012-01-01

    Objective To explore the effects of low dose X-ray irradiation on the ability of antigen presentation and IL-12 secretion in human dendritic cells that had been cultured for different time in vitro.Methods The human peripheral blood mononuclear cells ( PBMC ) were collected and differentiated to dendritic cells (DCs) by rhGM-CSF and rhIL-4 treatment in vitro.The DCs were divided into 3 groups,group A:DCs were cultured for 2 d and then irradiated with 0.05,0.1,0.2 and 0.5 Gy X-rays; group B:DCs were cultured for 6 d and then irradiated as above; group C:DCs were cultured without irradiation.At 8 d of cell culture,the DCs were applied to activate T cells and CCK-8 was used to detect MLR ( mixed lymphocyte reaction),and the antigen presentation ability of DCs was evaluated.MTT assay was also used to test the cell-killing effect of the activated T-cells on A549 cells.IL-12 in the culture medium of DCs was detected by ELISA.Results After irradiation with 0.2 and 0.5 Gy X-rays,the antigen presentation ability of DCs was decreased in group A (t =2.79 and 3.71,P < 0.05 ),but significantly increased in group B (t =3.60 and 3.11,P < 0.05).The ability of the T cell activation was detected and the proliferation of A549 cells was slightly inhibited by the DCs in group A (t =2.89 and 2.91,P < 0.05),but was obviously inhibited by the DCs in group B (t =2.91 and 2.82,P <0.05).Meanwhile,the level of IL-12 was dramatically decreased in group A (t =4.44 and 6.93,P < 0.05),but was increased in group B (t =3.51 and 4.12,P <0.05).Conclusions The abilities of antigen presentation and proliferation inhibition of DCs could be down-regulated by low dose( < 0.5 Gy) of X-ray irradiation at the early stage of DCs,but was up-regulated at the late stage of DCs culture.%目的 探讨小剂量x射线照射对体外不同培养时间的人外周血树突状细胞( dendritic cell,DC)抗原递呈及白介素-12(IL-12)分泌的影响.方法 分离人外周血单个核细胞(PBMC),以人

  8. Oncogenic cancer/testis antigens

    DEFF Research Database (Denmark)

    Gjerstorff, Morten F; Andersen, Mads H; Ditzel, Henrik J

    2015-01-01

    Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer....../testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor...... immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic...

  9. Antigenicity and Immunogenicity of Plasmodium vivax Merozoite Surface Protein-3

    OpenAIRE

    Amanda R Bitencourt; Elaine C Vicentin; Jimenez, Maria C.; Ricardo Ricci; Leite, Juliana A.; Fabio T Costa; Luis C Ferreira; Bruce Russell; François Nosten; Laurent Rénia; Galinski, Mary R.; Barnwell, John W.; Rodrigues, Mauricio M; Soares, Irene S

    2013-01-01

    A recent clinical trial in African children demonstrated the potential utility of merozoite surface protein (MSP)-3 as a vaccine against Plasmodium falciparum malaria. The present study evaluated the use of Plasmodium vivax MSP-3 (PvMSP-3) as a target antigen in vaccine formulations against malaria caused by P. vivax. Recombinant proteins representing MSP-3α and MSP-3β of P. vivax were expressed as soluble histidine-tagged bacterial fusions. Antigenicity during natural infection was evaluated...

  10. Natural Selection Promotes Antigenic Evolvability

    OpenAIRE

    Graves, C.J.; Ros, V.I.D.; Stevenson, B.; Sniegowski, P. D.; Brisson, D.

    2013-01-01

    The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed ‘cassettes...

  11. Anvendelse af prostataspecifikt antigen. En oversigt

    DEFF Research Database (Denmark)

    Brasso, K; Skaarup, P; Roosen, Jens Ulrik; Iversen, Peter

    1998-01-01

    Since it was first introduced, measurement of prostate specific antigen has gained increasing interest, and prostate specific antigen is regarded as being the best tumour marker available. The antigen lacks cancer specificity, limiting the usefulness in early diagnosis, The use of prostate specific...... antigen in early diagnosis, staging, and in monitoring patients with prostate cancer is reviewed....

  12. Challenges to the development of antigen-specific breast cancer vaccines

    International Nuclear Information System (INIS)

    Continued progress in the development of antigen-specific breast cancer vaccines depends on the identification of appropriate target antigens, the establishment of effective immunization strategies, and the ability to circumvent immune escape mechanisms. Methods such as T cell epitope cloning and serological expression cloning (SEREX) have led to the identification of a number target antigens expressed in breast cancer. Improved immunization strategies, such as using dendritic cells to present tumor-associated antigens to T lymphocytes, have been shown to induce antigen-specific T cell responses in vivo and, in some cases, objective clinical responses. An outcome of successful tumor immunity is the evolution of antigen-loss tumor variants. The development of a polyvalent breast cancer vaccine, directed against a panel of tumor-associated antigens, may counteract this form of immune escape

  13. Pattern of distribution of blood group antigens on human epidermal cells during maturation

    DEFF Research Database (Denmark)

    Dabelsteen, Erik; Buschard, Karsten; Hakomori, Sen-Itiroh

    1984-01-01

    The distribution in human epidermis of A, B, and H blood group antigens and of a precursor carbohydrate chain, N-acetyl-lactosamine, was examined using immunofluorescence staining techniques. The material included tissue from 10 blood group A, 4 blood group B, and 9 blood group O persons. Murine...... on the lower spinous cells whereas H antigen was seen predominantly on upper spinous cells or on the granular cells. Epithelia from blood group A or B persons demonstrated A or B antigens, respectively, but only if the tissue sections were trypsinized before staining. In such cases A or B antigens were found...... monoclonal antibodies were used to identify H antigen (type 2 chain) and N-acetyl-lactosamine. Human antisera were used to identify A and B antigens. In all groups N-acetyl-lactosamine and H antigen were found on the cell membranes of the spinous cell layer. N-acetyl-lactosamine was present mainly...

  14. Brain antigens: components of subfractions from human grey matter

    Science.gov (United States)

    Rajam, P. C.; Bogoch, S.

    1966-01-01

    1. Using chromatography on DEAE-cellulose, a neutral, low ionic strength extract of human grey matter has been separated into fractions of proteins with basic and progressively acidic groups. 2. The reactions of each group with rabbit antiserum against the original extract, in double-diffusion tests, suggest the presence of a minimum total of thirteen distinct antigens between them. These results are supported by immunoelectrophoretic findings, which indicate the basic group to contain five, and the progressively acidic group seven to eight distinct antigens. These antigens do not appear to be human serum proteins. 3. Antigens belonging to the BE class (resistant to boiling and relatively soluble in ethanol) are present among the progressively acidic proteins, and possibly among the basic proteins also. ImagesFIG. 2 PMID:4958737

  15. DNA encoding individual mycobacterial antigens protects mice against tuberculosis

    Directory of Open Access Journals (Sweden)

    C.L. Silva

    1999-02-01

    Full Text Available Over the last few years, some of our experiments in which mycobacterial antigens were presented to the immune system as if they were viral antigens have had a significant impact on our understanding of protective immunity against tuberculosis. They have also markedly enhanced the prospects for new vaccines. We now know that individual mycobacterial protein antigens can confer protection equal to that from live BCG vaccine in mice. A critical determinant of the outcome of immunization appears to be the degree to which antigen-specific cytotoxic T cells are generated by the immune response. Our most recent studies indicate that DNA vaccination is an effective way to establish long-lasting cytotoxic T cell memory and protection against tuberculosis.

  16. A new role for complement C3: regulation of antigen processing through an inhibitory activity.

    OpenAIRE

    Villiers, Christian; Cretin, François,; Lefebvre, Nicole; Marche, Patrice; Villiers, Marie-Bernadette

    2008-01-01

    International audience Increasing evidence underlines the involvement of complement component C3 in the establishment of acquired immunity which appears to play a complex role and to act at different levels. As antigen proteolysis by antigen presenting cells is a key event in the control of antigen presentation efficiency, and consequently in the quality of the immune response, we investigated whether C3 could modulate this step. Our results demonstrate for the first time that C3 can inter...

  17. Class II-targeted antigen is superior to CD40-targeted antigen at stimulating humoral responses in vivo.

    Science.gov (United States)

    Frleta, D; Demian, D; Wade, W F

    2001-02-01

    We examined the efficacy of using monoclonal antibodies to target antigen (avidin) to different surface molecules expressed on antigen presenting cells (APC). In particular, we targeted CD40 to test whether the "adjuvant" properties of CD40 signaling combined with targeted antigen would result in enhanced serologic responses. We targeted avidin to class II as a positive control and to CD11c as a negative control. These surface proteins represent an ensemble of surface molecules that signal upon ligation and that are expressed on professional APC, in particular dendritic cells (DC). We observed that targeting class II molecules on APC was superior to targeting CD40, or CD11c. However, CD40 and CD11c could function as targets for antigen bound monoclonal antibodies under certain conditions. Interestingly, inclusion of anti-CD40 mAb with the targeting anti-class II-targeted antigens negatively affects humoral response, suggesting that CD40 signaling under certain conditions may suppress processing and/or presentation of targeted antigen. PMID:11360928

  18. Neospora caninum: identification of 19-, 38-, and 40-kDa surface antigens and a 33-kDa dense granule antigen using monoclonal antibodies.

    Science.gov (United States)

    Schares, G; Dubremetz, J F; Dubey, J P; Bärwald, A; Loyens, A; Conraths, F J

    1999-06-01

    Neospora caninum, a coccidian parasite closely related to Toxoplasma gondii, can infect a broad host range and is regarded as an important cause of bovine abortion worldwide. In the present study, four antigens of N. caninum were partially characterized using monoclonal antibodies. Immunofluorescence of viable tachyzoites as well as the immunoprecipitation of antigens extracted from tachyzoites previously labeled by surface biotinylation revealed that three of these antigens with apparent molecular weights of 40, 38, and 19 kDa are located in the outer surface membrane of this parasite stage. Further evidence for the surface localization of the 38-kDa antigen was obtained by immunoelectron microscopy. In addition to the surface molecules, an antigen located in dense granules and in the tubular network of the parasitophorous vacuole was detected by another monoclonal antibody. When tachyzoite antigens separated under nonreducing conditions were probed on Western blots, this antibody reacted mainly with a 33-kDa antigen. Immunohistochemical analysis of infected tissue sections indicated that the 33-kDa dense granule antigen is present in both tachyzoites and bradyzoites, while the 38-kDa surface antigen from tachyzoites seems to be absent in bradyzoites. PMID:10366536

  19. T cells with chimeric antigen receptors have potent antitumor effects and can establish memory in patients with advanced leukemia.

    Science.gov (United States)

    Kalos, Michael; Levine, Bruce L; Porter, David L; Katz, Sharyn; Grupp, Stephan A; Bagg, Adam; June, Carl H

    2011-08-10

    Tumor immunotherapy with T lymphocytes, which can recognize and destroy malignant cells, has been limited by the ability to isolate and expand T cells restricted to tumor-associated antigens. Chimeric antigen receptors (CARs) composed of antibody binding domains connected to domains that activate T cells could overcome tolerance by allowing T cells to respond to cell surface antigens; however, to date, lymphocytes engineered to express CARs have demonstrated minimal in vivo expansion and antitumor effects in clinical trials. We report that CAR T cells that target CD19 and contain a costimulatory domain from CD137 and the T cell receptor ζ chain have potent non-cross-resistant clinical activity after infusion in three of three patients treated with advanced chronic lymphocytic leukemia (CLL). The engineered T cells expanded >1000-fold in vivo, trafficked to bone marrow, and continued to express functional CARs at high levels for at least 6 months. Evidence for on-target toxicity included B cell aplasia as well as decreased numbers of plasma cells and hypogammaglobulinemia. On average, each infused CAR-expressing T cell was calculated to eradicate at least 1000 CLL cells. Furthermore, a CD19-specific immune response was demonstrated in the blood and bone marrow, accompanied by complete remission, in two of three patients. Moreover, a portion of these cells persisted as memory CAR(+) T cells and retained anti-CD19 effector functionality, indicating the potential of this major histocompatibility complex-independent approach for the effective treatment of B cell malignancies. PMID:21832238

  20. Antigen-specific immune reactions to ischemic stroke

    Directory of Open Access Journals (Sweden)

    Xabier eUrra

    2014-09-01

    Full Text Available Brain proteins are detected in the CSF and blood of stroke patients and their concentration is related to the extent of brain damage. Antibodies against brain antigens develop after stroke, suggesting a humoral immune response to the brain injury. Furthermore, induced immune tolerance is beneficial in animal models of cerebral ischemia. The presence of circulating T cells sensitized against brain antigens, and antigen presenting cells (APCs carrying brain antigens in draining lymphoid tissue of stroke patients support the notion that stroke might induce antigen-specific immune responses. After stroke, brain proteins that are normally hidden from the periphery, inflammatory mediators, and danger signals can exit the brain through several efflux routes. They can reach the blood after leaking out of the damaged blood-brain barrier or following the drainage of interstitial fluid to the dural venous sinus, or reach the cervical lymph nodes through the nasal lymphatics following CSF drainage along the arachnoid sheaths of nerves across the nasal submucosa. The route and mode of access of brain antigens to lymphoid tissue could influence the type of response. Central and peripheral tolerance prevents autoimmunity, but the actual mechanisms of tolerance to brain antigens released into the periphery in the presence of inflammation, danger signals, and APCs, are not fully characterized. Stroke does not systematically trigger autoimmunity, but under certain circumstances, such as pronounced systemic inflammation or infection, autoreactive T cells could escape the tolerance controls. Further investigation is needed to elucidate whether antigen-specific immune events could underlie neurological complications impairing stroke outcome.

  1. Detection of peste des petits ruminants virus antigen using immunofiltration and antigen-competition ELISA methods.

    Science.gov (United States)

    Raj, G Dhinakar; Rajanathan, T M C; Kumar, C Senthil; Ramathilagam, G; Hiremath, Geetha; Shaila, M S

    2008-06-22

    Peste des petits ruminants (PPR) is one of the most economically important diseases affecting sheep and goats in India. An immunofiltration-based test has been developed using either mono-specific serum/monoclonal antibodies (mAb) prepared against a recombinant truncated nucleocapsid protein of rinderpest virus (RPV) cross-reactive with PPR virus. This method consists of coating ocular swab eluate from suspected animals onto a nitrocellulose membrane housed in a plastic module, which is allowed to react with suitable dilutions of a mAb or a mono-specific polyclonal antibody. The antigen-antibody complex formed on the membrane is then detected by protein A-colloidal gold conjugate, which forms a pink colour. In the immunofiltration test, concordant results were obtained using either PPRV mAb or mono-specific serum. Another test, an antigen-competition ELISA which relies on the competition between plate-coated recombinant truncated 'N' protein of RPV and the PPRV 'N' protein present in ocular swab eluates (sample) for binding to the mono-specific antibody against N protein of RPV (in liquid phase) was developed. The cut-off value for this test was established using reverse transcription polymerase chain reaction (RT-PCR) positive and negative oculo-nasal swab samples. Linear correlation between percent inhibition (PI) values in antigen-competition ELISA and virus infectivity titres was 0.992. Comparison of the immunofiltration test with the antigen-competition ELISA yielded a sensitivity of 80% and specificity of 100%. These two tests can serve as a screening (immunofiltration) and confirmatory (antigen-competition ELISA) test, respectively, in the diagnosis of PPR in sheep or goats. PMID:18182256

  2. Targeting novel antigens in the arterial wall in thromboangiitis obliterans.

    Directory of Open Access Journals (Sweden)

    Murat Akkus

    2010-06-01

    Full Text Available Thromboangiitis obliterans is an inflammatory disease possibly resulting from cigarette smoking as a primary etiologic factor, perhaps as a delayed type of hypersensitivity or toxic angiitis. As little is known about the pathogenesis of the disease, we aimed to determine novel antigens that might be responsible from the local inflammatory reactions and structural changes observed in this disease. An indirect immunoperoxidase technique is used to examine the tissue samples obtained from the dorsalis pedis artery of affected individuals with twenty monoclonal antibodies. Among these several antigens which are not previously reported in TAO like CD34, CD44 and CD90 were determined in the tissue samples examined. On the other hand, many other antigens like cytokine/chemokine receptors, several enzymes and leukocyte/lymphocyte antigens were lacking giving some clues about the local pathological reactions. We briefly discussed our findings for several critical antigens those first described in the present work, possibly having roles in the development of the disease. Expression of the CD90/CD11c receptor/ligand pair seems to play an important role in mononuclear cell recruitment to the damage site. Vascular invasion of not only tunica intima but also the tunica media in affected vessels is clearly demonstrated using endothelial cell specific antigens.

  3. [Farmer's lung antigens in Germany].

    Science.gov (United States)

    Sennekamp, J; Joest, M; Sander, I; Engelhart, S; Raulf-Heimsoth, M

    2012-05-01

    Recent studies suggest that besides the long-known farmer's lung antigen sources Saccharopolyspora rectivirgula (Micropolyspora faeni), Thermoactinomyces vulgaris, and Aspergillus fumigatus, additionally the mold Absidia (Lichtheimia) corymbifera as well as the bacteria Erwinia herbicola (Pantoea agglomerans) and Streptomyces albus may cause farmer's lung in Germany. In this study the sera of 64 farmers with a suspicion of farmer's lung were examined for the following further antigens: Wallemia sebi, Cladosporium herbarum, Aspergillus versicolor, and Eurotium amstelodami. Our results indicate that these molds are not frequent causes of farmer's lung in Germany. PMID:22477566

  4. Chylomicrons Promote Intestinal Absorption and Systemic Dissemination of Dietary Antigen (Ovalbumin) in Mice

    OpenAIRE

    Wang, Yuehui; Ghoshal, Sarbani; Ward, Martin; de Villiers, Willem; Woodward, Jerold; Eckhardt, Erik

    2009-01-01

    Background A small fraction of dietary protein survives enzymatic degradation and is absorbed in potentially antigenic form. This can trigger inflammatory responses in patients with celiac disease or food allergies, but typically induces systemic immunological tolerance (oral tolerance). At present it is not clear how dietary antigens are absorbed. Most food staples, including those with common antigens such as peanuts, eggs, and milk, contain long-chain triglycerides (LCT), which stimulate m...

  5. Major histocompatibility complex (MHC) antigens

    Czech Academy of Sciences Publication Activity Database

    Hála, K.; Plachý, Jiří; Kaufman, J.

    New York : Academic Press, 1998 - (Pastoret, P.; Griebel, P.; Bazin, H.; Govaerts, A.), s. 92-95 ISBN 0-12-546401-0 R&D Projects: GA ČR GA523/96/0670 Keywords : chicken MHC * histocompatibility antigens * disease resistance Subject RIV: EB - Genetics ; Molecular Biology

  6. Genome Scale Identification of Treponema pallidum Antigens

    OpenAIRE

    McKevitt, Matthew; Brinkman, Mary Beth; McLoughlin, Melanie; Perez, Carla; Howell, Jerrilyn K.; Weinstock, George M.; Norris, Steven J; Palzkill, Timothy

    2005-01-01

    Antibody responses for 882 of the 1,039 proteins in the proteome of Treponema pallidum were examined. Sera collected from infected rabbits were used to systematically identify 106 antigenic proteins, including 22 previously identified antigens and 84 novel antigens. Additionally, sera collected from rabbits throughout the course of infection demonstrated a progression in the breadth and intensity of humoral immunoreactivity against a representative panel of T. pallidum antigens.

  7. Detection of O antigens in Escherichia coli

    Science.gov (United States)

    Lipopolysaccharide on the surface of Escherichia coli constitute the O antigens, which are important virulence factors that are targets of both the innate and adaptive immune system and play a major role in host-pathogen interactions. O antigens that are responsible for antigenic specificity of the ...

  8. Plague virulence antigens from Yersinia enterocolitica.

    OpenAIRE

    Carter, P B; Zahorchak, R J; Brubaker, R R

    1980-01-01

    The virulence of Yersinia enterocolitica, biotype 2, serotype O:8, in mice is related to its ability to produce plague V and W antigens. V and W antigens in Y. enterocolitica are shown to be immunologically identical to the previously described V and W antigens of Yersinia pestis and Yersinia pseudotuberculosis.

  9. Molecular characterization of common treponemal antigens.

    OpenAIRE

    Hanff, P A; Miller, J N; Lovett, M A

    1983-01-01

    A molecular characterization of cross-reactive antigens of Treponema pallidum Nichols and Treponema phagedenis biotype Reiter that are reactive with normal and syphilitic human sera is described. At least 8 common polypeptides, 14 T. pallidum-specific antigens, and 2 T. phagedenis biotype Reiter-specific antigens were identified.

  10. A neuronal antigen in the brains of Alzheimer patients.

    Science.gov (United States)

    Wolozin, B L; Pruchnicki, A; Dickson, D W; Davies, P

    1986-05-01

    A monoclonal antibody was prepared against pooled homogenates of brain tissue from patients with Alzheimer's disease. This antibody recognizes an antigen present in much higher concentration in certain brain regions of Alzheimer patients than in normal brain. The antigen appears to be a protein present in neurons involved in the formation of neuritic plaques and neurofibrillary tangles, and in some morphologically normal neurons in sections from Alzheimer brains. Partial purification and Western blot analysis revealed the antigen from Alzheimer brain to be a single protein with a molecular weight of 68,000. Application of the same purification procedure to normal brain tissue results in the detection of small amounts of a protein of lower molecular weight. PMID:3083509

  11. Method to conjugate polysaccharide antigens to surfaces for the detection of antibodies

    DEFF Research Database (Denmark)

    Boas, Ulrik; Lind, Peter; Riber, Ulla

    2014-01-01

    A new generic method for the conjugation of lipopolysaccharide (LPS)-derived polysaccharide antigens from gram-negative bacteria has been developed using Salmonella as a model. After removal of lipid A from the LPS by mild acidolysis, the polysaccharide antigen was conjugated to polystyrene...... against Salmonella typhimurium and Salmonella dublin. The presented method was compared with a similar method for conjugation of Salmonella polysaccharide antigens to surfaces. Here, the new method showed higher antigen coupling efficiency by detecting low concentrations of antibodies. Furthermore, the...... polysaccharide-conjugated beads showed preserved bioactivity after 1 year of use....

  12. Low dose antigen promotes induction of FOXP3 in human CD4+ T cells

    OpenAIRE

    Long, S. Alice; Rieck, Mary; Tatum, Megan; Bollyky, Paul L.; Wu, Rebecca P.; Muller, Isabelle; Ho, Jhon-Chun; Shilling, Heather G.; Buckner, Jane H.

    2011-01-01

    Low antigen dose promotes induction and persistence of Treg in mice, yet few studies have addressed the role of antigen dose in the induction of adaptive CD4+FOXP3+ Treg in humans. To this end, we examined the level of FOXP3 expression in human CD4+CD25− T cells upon activation with autologous antigen presenting cells and varying doses of peptide. Antigen specific T cells expressing FOXP3 were identified by flow cytometry using MHC Class II tetramer (Tmr). We found an inverse relationship bet...

  13. Radioprotective activity of shigella antigens

    International Nuclear Information System (INIS)

    The possibility of using experimental microbe antigenous preparation out of Flexner and Zonne shigellas as a protector and a remedy in the case of gamma irradiation, is investigated. The experiments are carried out on mice of both sexes immunized before or after irradiation by two methods: subcutaneously and enerally. It is found that in most cases investigated, the introduction of the experimental preparation 3, 5, 7 and 10 days before irradiation increases the survivability of animals

  14. An antigen-specific, four-color, B-cell FluoroSpot assay utilizing tagged antigens for detection.

    Science.gov (United States)

    Jahnmatz, Peter; Bengtsson, Theresa; Zuber, Bartek; Färnert, Anna; Ahlborg, Niklas

    2016-06-01

    The FluoroSpot assay, a variant of ELISpot utilizing fluorescent detection, has so far been used primarily for assessment of T cells, where simultaneous detection of several cytokines has allowed a more qualitative analysis of functionally distinct T cells. The potential to measure multiple analytes also presents several advantages when analyzing B cells. Our aim was to develop a B-cell FluoroSpot assay adaptable to studies of a variety of antigens. The assay utilizes anti-IgG antibodies immobilized in 96-well filter membrane plates. During cell culture, IgG antibodies secreted by antibody-secreting cells (ASCs) are captured in the vicinity of each of these cells and the specificity of single ASCs is defined using antigens for detection. The antigens were labeled with biotin or peptide tags enabling secondary detection with fluorophore-conjugated streptavidin or tag-specific antibodies. The assay, utilizing up to four different tag systems and fluorophores simultaneously, was evaluated using hybridomas and immunized splenocytes as ASCs. Assay variants were developed that could: i) identify multiple ASCs with different antigen specificities; ii) detect ASCs showing cross-reactivity with different but related antigens; and iii) define the antigen-specificity and, by including anti-IgG subclass detection reagents, simultaneously determine the IgG subclass of antibodies secreted by ASCs. As demonstrated here, the B-cell FluoroSpot assay using tag-based detection systems provides a versatile and powerful tool to investigate antibody responses by individual cells that can be readily adapted to studies of a variety of antigen-specific ASCs. PMID:26930550

  15. Present time

    OpenAIRE

    Romero, Gustavo E.

    2014-01-01

    The idea of a moving present or `now' seems to form part of our most basic beliefs about reality. Such a present, however, is not reflected in any of our theories of the physical world. I show in this article that presentism, the doctrine that only what is present exists, is in conflict with modern relativistic cosmology and recent advances in neurosciences. I argue for a tenseless view of time, where what we call `the present' is just an emergent secondary quality arising from the interactio...

  16. Present time

    CERN Document Server

    Romero, Gustavo E

    2014-01-01

    The idea of a moving present or `now' seems to form part of our most basic beliefs about reality. Such a present, however, is not reflected in any of our theories of the physical world. I show in this article that presentism, the doctrine that only what is present exists, is in conflict with modern relativistic cosmology and recent advances in neurosciences. I argue for a tenseless view of time, where what we call `the present' is just an emergent secondary quality arising from the interaction of perceiving self-conscious individuals with their environment. I maintain that there is no flow of time, but just an ordered system of events.

  17. Immunological characterization of a recombinant 27-kilodalton antigenic protein from Paracoccidioides brasiliensis.

    OpenAIRE

    Ortiz, B L; Garcia, A. M.; A. Restrepo; McEwen, J. G.

    1996-01-01

    We report the expression in Escherichia coli of a 27-kDa antigenic protein from Paracoccidioides brasiliensis. When analyzed by immunoblotting, this recombinant antigenic protein was recognized by antibodies present in the sera of 40 of the 44 paracoccidioidomycosis patients studied. No cross-reactions were observed with sera from patients with other mycoses (histoplasmosis, aspergillosis, cryptococcosis, sporotrichosis, and chromoblastomycosis) or with tuberculosis.

  18. Multivalent glycopeptide dendrimers for the targeted delivery of antigens to dendritic cells

    NARCIS (Netherlands)

    J.J. García-Vallejo; M. Ambrosini; A. Overbeek; W.E. van Riel; K. Bloem; W.W.J. Unger; F. Chiodo; J.G. Bolscher; K. Nazmi; H. Kalay; Y. van Kooyk

    2013-01-01

    Dendritic cells are the most powerful type of antigen presenting cells. Current immunotherapies targeting dendritic cells have shown a relative degree of success but still require further improvement. One of the most important issues to solve is the efficiency of antigen delivery to dendritic cells

  19. Production of Trichophyton mentagrophytes antigens and their characterization in mice

    Directory of Open Access Journals (Sweden)

    J Venturini

    2008-01-01

    Full Text Available The participation of dermatophytic antigens in the host-parasite balance is still poorly understood. One of the difficulties encountered by researchers is the lack of dominant and specific antigens that can be used in such studies. In order to contribute to a better understanding of this aspect of infection, the present study identifies antigen fractions obtained from exoantigen and cytoplasmic extracts of Trichophyton mentagrophytes. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE revealed the presence of 13 proteins in the exoantigen extract, whose molecular weight ranged from 12.5 to 90 kDa. The cytoplasmic extract contained 18 protein fractions ranging from 11 to 110 kDa. Immunoblotting showed the presence of immunodominant antigens against IgG, IgM and IgA antibodies. This affinity was observed in three proteins of the exoantigen extract and in three proteins of the cytoplasmic extract, with respective molecular weights of 33, 39 and 59, and 40, 55 and 82 kDa. These results are promising, especially when considering that these extracts contain antigenically distinct protein fractions which, once determined, may contribute to a better understanding of dermatophytoses, and may thus help in the development of alternative strategies for the diagnosis and treatment of this condition.

  20. The global antigenic diversity of swine influenza A viruses

    Science.gov (United States)

    Lewis, Nicola S; Russell, Colin A; Langat, Pinky; Anderson, Tavis K; Berger, Kathryn; Bielejec, Filip; Burke, David F; Dudas, Gytis; Fonville, Judith M; Fouchier, Ron AM; Kellam, Paul; Koel, Bjorn F; Lemey, Philippe; Nguyen, Tung; Nuansrichy, Bundit; Peiris, JS Malik; Saito, Takehiko; Simon, Gaelle; Skepner, Eugene; Takemae, Nobuhiro; Webby, Richard J; Van Reeth, Kristien; Brookes, Sharon M; Larsen, Lars; Watson, Simon J; Brown, Ian H; Vincent, Amy L

    2016-01-01

    Swine influenza presents a substantial disease burden for pig populations worldwide and poses a potential pandemic threat to humans. There is considerable diversity in both H1 and H3 influenza viruses circulating in swine due to the frequent introductions of viruses from humans and birds coupled with geographic segregation of global swine populations. Much of this diversity is characterized genetically but the antigenic diversity of these viruses is poorly understood. Critically, the antigenic diversity shapes the risk profile of swine influenza viruses in terms of their epizootic and pandemic potential. Here, using the most comprehensive set of swine influenza virus antigenic data compiled to date, we quantify the antigenic diversity of swine influenza viruses on a multi-continental scale. The substantial antigenic diversity of recently circulating viruses in different parts of the world adds complexity to the risk profiles for the movement of swine and the potential for swine-derived infections in humans. DOI: http://dx.doi.org/10.7554/eLife.12217.001 PMID:27113719

  1. A new antigen retrieval technique for human brain tissue.

    Directory of Open Access Journals (Sweden)

    Raúl Alelú-Paz

    Full Text Available Immunohistochemical staining of tissues is a powerful tool used to delineate the presence or absence of an antigen. During the last 30 years, antigen visualization in human brain tissue has been significantly limited by the masking effect of fixatives. In the present study, we have used a new method for antigen retrieval in formalin-fixed human brain tissue and examined the effectiveness of this protocol to reveal masked antigens in tissues with both short and long formalin fixation times. This new method, which is based on the use of citraconic acid, has not been previously utilized in brain tissue although it has been employed in various other tissues such as tonsil, ovary, skin, lymph node, stomach, breast, colon, lung and thymus. Thus, we reported here a novel method to carry out immunohistochemical studies in free-floating human brain sections. Since fixation of brain tissue specimens in formaldehyde is a commonly method used in brain banks, this new antigen retrieval method could facilitate immunohistochemical studies of brains with prolonged formalin fixation times.

  2. Stimulation of T-cell activation by UV-treated, antigen-pulsed macrophages: evidence for a requirement for antigen processing and interleukin 1 secretion

    International Nuclear Information System (INIS)

    The nature of the defect(s) in the ability of UV-treated guinea pig macrophages to stimulate the proliferative response of guinea pig T cells to soluble protein antigens was investigated. T cells proliferated vigorously when cultured with peritoneal exudate cells (PEC) which had been pulsed with soluble protein antigens, but failed to proliferate when cultured with soluble antigen or with antigen-pulsed, UV-treated PEC. UV-treated macrophages were unable to secrete interleukin 1 (IL-1). Addition of IL-1 partially restored the T-cell proliferative response stimulated by antigen-pulsed, UV-treated PEC. However, IL-1 was able to restore such a response only when the PEC were pulsed with antigen before being exposed to UV. Similar results were obtained when antigen-pulsed PEC were used to stimulate T cells to secrete interleukin 2 (IL-2). These results demonstrate that UV-treated macrophages are defective both in their ability to properly process and present antigen for T-cell recognition and in their ability to secrete IL-1

  3. Differential use of autophagy by primary dendritic cells specialized in cross-presentation.

    Science.gov (United States)

    Mintern, Justine D; Macri, Christophe; Chin, Wei Jin; Panozza, Scott E; Segura, Elodie; Patterson, Natalie L; Zeller, Peter; Bourges, Dorothee; Bedoui, Sammy; McMillan, Paul J; Idris, Adi; Nowell, Cameron J; Brown, Andrew; Radford, Kristen J; Johnston, Angus Pr; Villadangos, Jose A

    2015-01-01

    Antigen-presenting cells survey their environment and present captured antigens bound to major histocompatibility complex (MHC) molecules. Formation of MHC-antigen complexes occurs in specialized compartments where multiple protein trafficking routes, still incompletely understood, converge. Autophagy is a route that enables the presentation of cytosolic antigen by MHC class II molecules. Some reports also implicate autophagy in the presentation of extracellular, endocytosed antigen by MHC class I molecules, a pathway termed "cross-presentation." The role of autophagy in cross-presentation is controversial. This may be due to studies using different types of antigen presenting cells for which the use of autophagy is not well defined. Here we report that active use of autophagy is evident only in DC subtypes specialized in cross-presentation. However, the contribution of autophagy to cross-presentation varied depending on the form of antigen: it was negligible in the case of cell-associated antigen or antigen delivered via receptor-mediated endocytosis, but more prominent when the antigen was a soluble protein. These findings highlight the differential use of autophagy and its machinery by primary cells equipped with specific immune function, and prompt careful reassessment of the participation of this endocytic pathway in antigen cross-presentation. PMID:25950899

  4. Antigenic specificity of serum antibodies in mice fed soy protein

    DEFF Research Database (Denmark)

    Christensen, Hanne Risager; Bruun, S.W.; Frøkiær, Hanne

    2003-01-01

    the relationship between the immunogenic proteins involved in this nondeleterious antibody response and the pathological response associated with food allergy. The objective of the present study was to characterize the antigenic specificity of the soy protein-specific antibody response generated in...... healthy mice ingesting soy protein. Methods: Blood from mice fed a soy-containing diet was analyzed using ELISA and immunoblot for antibody reactivity towards various soy protein fractions and pure soy proteins/subunits. Mice bred on a soy-free diet were used as controls. Results: The detectable antigenic...

  5. Artificial Loading of ASC Specks with Cytosolic Antigens.

    Directory of Open Access Journals (Sweden)

    Ali Can Sahillioğlu

    Full Text Available Inflammasome complexes form upon interaction of Nod Like Receptor (NLR proteins with pathogen associated molecular patterns (PAPMS inside the cytosol. Stimulation of a subset of inflammasome receptors including NLRP3, NLRC4 and AIM2 triggers formation of the micrometer-sized spherical supramolecular complex called the ASC speck. The ASC speck is thought to be the platform of inflammasome activity, but the reason why a supramolecular complex is preferred against oligomeric platforms remains elusive. We observed that a set of cytosolic proteins, including the model antigen ovalbumin, tend to co-aggregate on the ASC speck. We suggest that co-aggregation of antigenic proteins on the ASC speck during intracellular infection might be instrumental in antigen presentation.

  6. Oxidative stress can alter the antigenicity of immunodominant peptides

    DEFF Research Database (Denmark)

    Weiskopf, Daniela; Schwanninger, Angelika; Weinberger, Birgit; Almanzar, Giovanni; Parson, Walther; Buus, Søren; Lindner, Herbert; Grubeck-Loebenstein, Beatrix

    2010-01-01

    APCs operate frequently under oxidative stress induced by aging, tissue damage, pathogens, or inflammatory responses. Phagocytic cells produce peroxides and free-radical species that facilitate pathogen clearance and can in the case of APCs, also lead to oxidative modifications of antigenic...... proteins and peptides. Little information is available presently about the consequences of such modifications on the immune response. To model oxidative modification of an immunodominant antigenic peptide, we oxidized the methionine residue of the human CMV pp65(495-503) (NLVPMVATV) peptide. Such...... modifications of an antigenic peptide can affect MHC binding or TCR recognition. Using binding and dissociation assays, we demonstrate that oxidative modification of the CMVpp65(495-503) peptide leads to a decreased binding of the pMHC complex to the TCR, whereas binding of the peptide to the MHC class I...

  7. A Model System for Concurrent Detection of Antigen and Antibody Based on Immunological Fluorescent Method

    Directory of Open Access Journals (Sweden)

    Yuan-Cheng Cao

    2015-01-01

    Full Text Available This paper describes a combined antigen/antibody immunoassay implemented in a 96-well plate using fluorescent spectroscopic method. First, goat anti-human IgG was used to capture human IgG (model antigen; goat anti-human IgG (Cy3 or FITC was used to detect the model antigen; a saturating level of model antigen was then added followed by unlabelled goat anti-human IgG (model antibody; finally, Cy3 labelled rabbit anti-goat IgG was used to detect the model antibody. Two approaches were applied to the concomitant assay to analyze the feasibility. The first approach applied FITC and Cy3 when both targets were present at the same time, resulting in 50 ng/mL of the antibody detection limit and 10 ng/mL of antigen detection limit in the quantitative measurements of target concentration, taking the consideration of FRET efficiency of 68% between donor and acceptor. The sequential approach tended to lower the signal/noise (S/N ratio and the detection of the model antigen (lower than 1 ng/mL had better sensitivity than the model antibody (lower than 50 ng/mL. This combined antigen/antibody method might be useful for combined detection of antigens and antibodies. It will be helpful to screen for both antigen and antibody particularly in the situations of the multiserotype and high-frequency mutant virus infections.

  8. T Cells Expressing CD19/CD20 Bispecific Chimeric Antigen Receptors Prevent Antigen Escape by Malignant B Cells.

    Science.gov (United States)

    Zah, Eugenia; Lin, Meng-Yin; Silva-Benedict, Anne; Jensen, Michael C; Chen, Yvonne Y

    2016-06-01

    The adoptive transfer of T cells expressing anti-CD19 chimeric antigen receptors (CARs) has shown remarkable curative potential against advanced B-cell malignancies, but multiple trials have also reported patient relapses due to the emergence of CD19-negative leukemic cells. Here, we report the design and optimization of single-chain, bispecific CARs that trigger robust cytotoxicity against target cells expressing either CD19 or CD20, two clinically validated targets for B-cell malignancies. We determined the structural parameters required for efficient dual-antigen recognition, and we demonstrate that optimized bispecific CARs can control both wild-type B-cell lymphoma and CD19(-) mutants with equal efficiency in vivo To our knowledge, this is the first bispecific CAR capable of preventing antigen escape by performing true OR-gate signal computation on a clinically relevant pair of tumor-associated antigens. The CD19-OR-CD20 CAR is fully compatible with existing T-cell manufacturing procedures and implementable by current clinical protocols. These results present an effective solution to the challenge of antigen escape in CD19 CAR T-cell therapy, and they highlight the utility of structure-based rational design in the development of receptors with higher-level complexity. Cancer Immunol Res; 4(6); 498-508. ©2016 AACRSee related Spotlight by Sadelain, p. 473. PMID:27059623

  9. The Prognostic, Diagnostic, and Therapeutic Potential of Tumor Antigens

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn

    Tumor antigens are a group of proteins recognized by the cells of immune system. Specifically, they are recognized in tumor cells where they are present in larger than usual amounts, or are physiochemically altered to a degree at which they no longer resemble native human proteins. Their presence...

  10. Tumor antigens as proteogenomic biomarkers in invasive ductal carcinomas

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn; Campos, Benito; Winther, Ole;

    2014-01-01

    found to be perturbed. Conclusion: Tumor antigens are a group of proteins recognized by the cells of the immune system. Specifically, they are recognized in tumor cells where they are present in larger than usual amounts, or are physiochemically altered to a degree at which they no longer resemble...

  11. CATCHY PRESENTATIONS

    DEFF Research Database (Denmark)

    Eriksen, Kaare; Tollestrup, Christian; Ovesen, Nis

    2011-01-01

    and ideas in many areas and avoiding “Death by Powerpoint”. This paper discusses the need and tools for making short presentations and describes the result from a business development project where engineering graduate students in architecture and design used the Pecha Kucha format to present their...

  12. 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...... attractive interaction with the zwitterionic liposomes. In contrast, the net cationic lysozyme showed very little interaction with either types of liposome. Adsorption of α-lactalbumin altered its tertiary structure, affected lipid membrane packing below and above the phase transition temperature, and...... way vaccine antigens are presented to antigen-presenting cells, and may play an important role for the efficacy of the vaccine-induced immune response. These studies thus exemplify the importance of characterizing the molecular interactions between the vaccine antigen and adjuvant along with...

  13. An accurate radioimmunoassay of human growth hormone with separation on polyacrylamide gel electrophoresis of free antigen, antigen-antibody complex and damaged labelled antigen. Further study of damaged labelled antigen to obtain long-lasting labelled products

    International Nuclear Information System (INIS)

    The purpose of this work was to obtain a radioimmunoassay that would be sufficiently accurate and precise to provide a suitable means of determining human growth hormone (hGH) in both extracts and physiological fluids for specific research purposes rather than for routine clinical assays where the labelled products could be used as long as possible. The only technique found that could satisfy these requirements was polyacrylamide gel electrophoresis (PAGE), though in some respects it is more laborious than other techniques. By introducing some modifications to the original method of Davis it was possible, with 11-cm tubes, to separate the free, the antibody-bound, and the damaged labelled antigen on the same gel. The method, being able to detect separately and independently these three components and to give a better control of the analytically dangerous ''damaged'' antigens, furnished accurate and reproducible curves. An example of a determination is the one on KABI-Crescormon which compares the results obtained with the present technique with those presented by another laboratory. Thanks to this method, the labelled antigen could be used for up to one month, after which re-purification on Sephadex enabled the same labelled product to be used profitably for two more months. Parallel to this work, a study has been performed on the various components originating in this so-called process of ''damaging'', and particular importance has been given to a more precise knowledge of the amount of antigen, in terms of mass, present in an assay. (author)

  14. Histocompatibility antigens on astrocytoma cells.

    OpenAIRE

    Hirschberg, H.; Endresen, L I; Wikeby, P

    1982-01-01

    Biopsies tumour cells from astrocytoma-bearing patients were grown in primary culture for 3-5 days. Both low and high grade tumours were represented in the study. The cultured cells could be shown to express the HLA-A and -B antigens using a multispecific allo-antiserum and a rabbit anti-beta-2 microglobulin antibody. The tumour cells were negative for the HLA-DR determinants when tested with either rabbit anti-Ia-like antisera or specific anti-HLA-DR allo-antisera. They also failed to stimul...

  15. The antigenic properties of human prolactin

    International Nuclear Information System (INIS)

    The antigenic properties of human prolactin (HPr) were studied using various methods of radio-immuno assay. The homologous system, the difficulty of which resides in the preparation of the tracer, easily permits measurement of physiological levels. In this system, blood prolactin in the monkey has an antigenicity comparable with that of human prolactin, whereas growth hormone and human chorionic somatotropin have feeble or nil antigenic relationship with HPr. Human, sheep and pig prolactins have variable antigenic cross-reactions depending on the immune serum used. These antigenic cross reactions may be applied to the isolation of amniotic prolactin. Human blood prolactin has several components of different molecular weight, but antigenicity comparable with that of pituitary HPr

  16. Functional Development of the T Cell Receptor for Antigen

    Science.gov (United States)

    Ebert, Peter J.R.; Li, Qi-Jing; Huppa, Johannes B.; Davis, Mark M.

    2016-01-01

    For over three decades now, the T cell receptor (TCR) for antigen has not ceased to challenge the imaginations of cellular and molecular immunologists alike. T cell antigen recognition transcends every aspect of adaptive immunity: it shapes the T cell repertoire in the thymus and directs T cell-mediated effector functions in the periphery, where it is also central to the induction of peripheral tolerance. Yet, despite its central position, there remain many questions unresolved: how can one TCR be specific for one particular peptide-major histocompatibility complex (pMHC) ligand while also binding other pMHC ligands with an immunologically relevant affinity? And how can a T cell’s extreme specificity (alterations of single methyl groups in their ligand can abrogate a response) and sensitivity (single agonist ligands on a cell surface are sufficient to trigger a measurable response) emerge from TCR–ligand interactions that are so low in affinity? Solving these questions is intimately tied to a fundamental understanding of molecular recognition dynamics within the many different contexts of various T cell–antigen presenting cell (APC) contacts: from the thymic APCs that shape the TCR repertoire and guide functional differentiation of developing T cells to the peripheral APCs that support homeostasis and provoke antigen responses in naïve, effector, memory, and regulatory T cells. Here, we discuss our recent findings relating to T cell antigen recognition and how this leads to the thymic development of foreign-antigen-responsive αβT cells. PMID:20800817

  17. The antigenicity of tobacco mosaic virus.

    OpenAIRE

    Van Regenmortel, M H

    1999-01-01

    The antigenic properties of the tobacco mosaic virus (TMV) have been studied extensively for more than 50 years. Distinct antigenic determinants called neotopes and cryptotopes have been identified at the surface of intact virions and dissociated coat protein subunits, respectively, indicating that the quaternary structure of the virus influences the antigenic properties. A correlation has been found to exist between the location of seven to ten residue-long continuous epitopes in the TMV coa...

  18. Histocompatibility antigens in coal miners with pneumoconiosis.

    OpenAIRE

    Soutar, C A; Coutts, I.; Parkes, W R; Dodi, I. A.; Gauld, S; Castro, J E; Turner-Warwick, M

    1983-01-01

    Twenty-five histocompatibility antigens have been measured in 100 coal miners with pneumoconiosis attending a pneumoconiosis medical panel and the results compared with a panel of 200 normal volunteers not exposed to dust. Chest radiographs were read independently by three readers according to the ILO U/C classification. On a combined score, 40 men were thought to have simple pneumoconiosis and 60 men complicated pneumoconiosis. The number of antigens tested and associations between antigens ...

  19. Isolation of Fasciola hepatica tegument antigens.

    OpenAIRE

    Hillyer, G. V.

    1980-01-01

    Fasciola hepatica tegument antigens were isolated from intact worms in the cold by using Nonidet P-40. Proof of the tegumental nature of the antigens was shown by the peroxidase-antiperoxidase immunocytochemical technique at the light microscope level. The potential of F. hepatica tegument antigens for the immunodiagnosis of rabbit and human fascioliasis was shown by Ouchterlony immunodiffusion, although cross-reactivity was evident in one of six serum samples from patients infected with Schi...

  20. Lecture Presentations

    International Nuclear Information System (INIS)

    The Symposium on Physics of Elementary Interactions in the LHC Era held in Warsaw from 21 to 22 April 2008. The main subject of the workshop was to present the progress in CERN LHC collider project. Additionally some satellite activities in field of education, knowledge and technology transfer in the frame of CERN - Poland cooperation were shown

  1. Engineering antigen-specific immunological tolerance.

    Energy Technology Data Exchange (ETDEWEB)

    Kontos, Stephan; Grimm, Alizee J.; Hubbell, Jeffrey A.

    2015-05-01

    Unwanted immunity develops in response to many protein drugs, in autoimmunity, in allergy, and in transplantation. Approaches to induce immunological tolerance aim to either prevent these responses or reverse them after they have already taken place. We present here recent developments in approaches, based on engineered peptides, proteins and biomaterials, that harness mechanisms of peripheral tolerance both prophylactically and therapeutically to induce antigenspecific immunological tolerance. These mechanisms are based on responses of B and T lymphocytes to other cells in their immune environment that result in cellular deletion or ignorance to particular antigens, or in development of active immune regulatory responses. Several of these approaches are moving toward clinical development, and some are already in early stages of clinical testing.

  2. Technical presentation

    CERN Multimedia

    FI Department

    2008-01-01

    RADIOSPARES, the leading catalogue distributor of components (electronic, electrical, automation, etc.) and industrial supplies will be at CERN on Friday 3 October 2008 (Main Building, Room B, from 9.00 a.m. to 3.00 p.m.) to introduce its new 2008/2009 catalogue. This will be the opportunity for us to present our complete range of products in more detail: 400 000 part numbers available on our web site (Radiospares France, RS International, extended range of components from other manufacturers); our new services: quotations, search for products not included in the catalogue, SBP products (Small Batch Production: packaging in quantities adapted to customers’ requirements); partnership with our focus manufacturers; demonstration of the on-line purchasing tool implemented on our web site in conjunction with CERN. RADIOSPARES will be accompanied by representatives of FLUKE and TYCO ELECTRONICS, who will make presentations, demonstrate materials and answer any technical questio...

  3. Defining cross presentation for a wider audience.

    Science.gov (United States)

    Norbury, Christopher C

    2016-06-01

    Cross presentation is the process of production of peptide-MHC Class I complexes by cells in which the antigen that is the source of peptide is not translated. The majority of recent studies have described many facets of the classical TAP-dependent cross presentation pathway, but numerous pathways for transfer of antigenic material from a donor to a recipient cell followed by subsequent MHC-I-restricted presentation have been established, including transfer of protein antigen, peptide, RNA, DNA or even peptide-MHC-I complexes. The extent to which each of these pathways generates overlapping or unique peptide repertoires is unknown, as is the contribution of each of these pathways to generation of protective CD8+ T cells during infection or anti-tumor immune responses. PMID:27101579

  4. Targeted delivery of lipid antigen to macrophages via the CD169/sialoadhesin endocytic pathway induces robust invariant natural killer T cell activation

    OpenAIRE

    Kawasaki, Norihito; Vela, Jose Luis; Nycholat, Corwin M.; Rademacher, Christoph; Khurana, Archana; van Rooijen, Nico; Crocker, Paul R.; Kronenberg, Mitchell; Paulson, James C.

    2013-01-01

    Invariant natural killer T (iNKT) cells induce a protective immune response triggered by foreign glycolipid antigens bound to CD1d on antigen-presenting cells (APCs). A limitation of using glycolipid antigens to stimulate immune responses in human patients has been the inability to target them to the most effective APCs. Recent studies have implicated phagocytic CD169+ macrophages as major APCs in lymph nodes for priming iNKT cells in mice immunized with glycolipid antigen in particulate form...

  5. Liposomes Containing Lipid A Serve as an Adjuvant for Induction of Antibody and Cytotoxic T-Cell Responses against RTS,S Malaria Antigen

    OpenAIRE

    Richards, Roberta L.; Rao, Mangala; Wassef, Nabila M.; Glenn, Gregory M.; Rothwell, Stephen W.; Alving, Carl R.

    1998-01-01

    Encapsulation of soluble protein antigens in liposomes was previously shown to result in processing of antigen via the major histocompatibility complex class I pathway, as evidenced by costaining of the trans-Golgi region of murine bone marrow-derived macrophages (BMs) by fluorophore-labeled liposomal antigen and by a trans-Golgi-specific fluorescent lipid. Evidence is presented here that free or liposome-encapsulated RTS,S, a particulate malaria antigen consisting of hepatitis B particles co...

  6. Urinary IgG antibody against mixed heat-killed coliform antigen and lipopolysaccharide core antigen.

    OpenAIRE

    Gibb, A P; Edmond, D. M.

    1992-01-01

    AIMS: To determine whether antibody to lipopolysaccharide-core (LPS-core) antigen is an important component of the antibody, detected by mixed heat-killed coliform antigen, in urine from patients with suspected urinary tract infection. METHODS: LPS-core antigen and mixed heat-killed coliform antigen were used in an enzyme linked immunosorbent assay (ELISA) to measure IgG antibody in midstream urine samples. Seventy two samples from students attending their general practitioner with symptoms s...

  7. Blastogenic response of human lymphocytes to early antigen(s) of human cytomegalovirus.

    OpenAIRE

    Waner, J L; Kong, N; Biano, S

    1983-01-01

    The lymphocytes of asymptomatic, seropositive donors demonstrated blastogenic responses to early antigens of human cytomegalovirus whether or not antibodies to early antigens were detectable. The lymphocytes of six of nine patients with active cytomegalovirus infections gave stimulation indexes of greater than or equal to 2.00 with antigens of productively infected cells, whereas only two patients demonstrated comparable stimulation indexes with early antigens. Four patients with stimulation ...

  8. Common Ewing sarcoma-associated antigens fail to induce natural T cell responses in both patients and healthy individuals.

    Science.gov (United States)

    Altvater, Bianca; Kailayangiri, Sareetha; Theimann, Nadine; Ahlmann, Martina; Farwick, Nicole; Chen, Christiane; Pscherer, Sibylle; Neumann, Ilka; Mrachatz, Gabriele; Hansmeier, Anna; Hardes, Jendrik; Gosheger, Georg; Juergens, Heribert; Rossig, Claudia

    2014-10-01

    Disseminated or relapsed Ewing sarcoma (EwS) has remained fatal in the majority of patients. A promising approach to preventing relapse after conventional therapy is to establish tumor antigen-specific immune control. Efficient and specific T cell memory against the tumor depends on the expansion of rare T cells with native specificity against target antigens overexpressed by the tumor. Candidate antigens in EwS include six-transmembrane epithelial antigen of the prostate-1 (STEAP1), and the human cancer/testis antigens X-antigen family member 1 (XAGE1) and preferentially expressed antigen in melanoma (PRAME). Here, we screened normal donors and EwS patients for the presence of circulating T cells reactive with overlapping peptide libraries of these antigens by IFN-γ Elispot analysis. The majority of 22 healthy donors lacked detectable memory T cell responses against STEAP1, XAGE1 and PRAME. Moreover, ex vivo detection of T cells specific for these antigens in both blood and bone marrow were limited to a minority of EwS patients and required nonspecific T cell prestimulation. Cytotoxic T cells specific for the tumor-associated antigens were efficiently and reliably generated by in vitro priming using professional antigen-presenting cells and optimized cytokine stimulation; however, these T cells failed to interact with native antigen processed by target cells and with EwS cells expressing the antigen. We conclude that EwS-associated antigens fail to induce efficient T cell receptor (TCR)-mediated antitumor immune responses even under optimized conditions. Strategies based on TCR engineering could provide a more effective means to manipulating T cell immunity toward targeted elimination of tumor cells. PMID:24973179

  9. Antigenicity and immunogenicity of Plasmodium vivax merozoite surface protein-3.

    Science.gov (United States)

    Bitencourt, Amanda R; Vicentin, Elaine C; Jimenez, Maria C; Ricci, Ricardo; Leite, Juliana A; Costa, Fabio T; Ferreira, Luis C; Russell, Bruce; Nosten, François; Rénia, Laurent; Galinski, Mary R; Barnwell, John W; Rodrigues, Mauricio M; Soares, Irene S

    2013-01-01

    A recent clinical trial in African children demonstrated the potential utility of merozoite surface protein (MSP)-3 as a vaccine against Plasmodium falciparum malaria. The present study evaluated the use of Plasmodium vivax MSP-3 (PvMSP-3) as a target antigen in vaccine formulations against malaria caused by P. vivax. Recombinant proteins representing MSP-3α and MSP-3β of P. vivax were expressed as soluble histidine-tagged bacterial fusions. Antigenicity during natural infection was evaluated by detecting specific antibodies using sera from individuals living in endemic areas of Brazil. A large proportion of infected individuals presented IgG antibodies to PvMSP-3α (68.2%) and at least 1 recombinant protein representing PvMSP-3β (79.1%). In spite of the large responder frequency, reactivity to both antigens was significantly lower than was observed for the immunodominant epitope present on the 19-kDa C-terminal region of PvMSP-1. Immunogenicity of the recombinant proteins was studied in mice in the absence or presence of different adjuvant formulations. PvMSP-3β, but not PvMSP-3α, induced a TLR4-independent humoral immune response in the absence of any adjuvant formulation. The immunogenicity of the recombinant antigens were also tested in formulations containing different adjuvants (Alum, Salmonella enterica flagellin, CpG, Quil A,TiterMax® and incomplete Freunds adjuvant) and combinations of two adjuvants (Alum plus flagellin, and CpG plus flagellin). Recombinant PvMSP-3α and PvMSP-3β elicited higher antibody titers capable of recognizing P. vivax-infected erythrocytes harvested from malaria patients. Our results confirm that P. vivax MSP-3 antigens are immunogenic during natural infection, and the corresponding recombinant proteins may be useful in elucidating their vaccine potential. PMID:23457498

  10. Antigenicity and immunogenicity of Plasmodium vivax merozoite surface protein-3.

    Directory of Open Access Journals (Sweden)

    Amanda R Bitencourt

    Full Text Available A recent clinical trial in African children demonstrated the potential utility of merozoite surface protein (MSP-3 as a vaccine against Plasmodium falciparum malaria. The present study evaluated the use of Plasmodium vivax MSP-3 (PvMSP-3 as a target antigen in vaccine formulations against malaria caused by P. vivax. Recombinant proteins representing MSP-3α and MSP-3β of P. vivax were expressed as soluble histidine-tagged bacterial fusions. Antigenicity during natural infection was evaluated by detecting specific antibodies using sera from individuals living in endemic areas of Brazil. A large proportion of infected individuals presented IgG antibodies to PvMSP-3α (68.2% and at least 1 recombinant protein representing PvMSP-3β (79.1%. In spite of the large responder frequency, reactivity to both antigens was significantly lower than was observed for the immunodominant epitope present on the 19-kDa C-terminal region of PvMSP-1. Immunogenicity of the recombinant proteins was studied in mice in the absence or presence of different adjuvant formulations. PvMSP-3β, but not PvMSP-3α, induced a TLR4-independent humoral immune response in the absence of any adjuvant formulation. The immunogenicity of the recombinant antigens were also tested in formulations containing different adjuvants (Alum, Salmonella enterica flagellin, CpG, Quil A,TiterMax® and incomplete Freunds adjuvant and combinations of two adjuvants (Alum plus flagellin, and CpG plus flagellin. Recombinant PvMSP-3α and PvMSP-3β elicited higher antibody titers capable of recognizing P. vivax-infected erythrocytes harvested from malaria patients. Our results confirm that P. vivax MSP-3 antigens are immunogenic during natural infection, and the corresponding recombinant proteins may be useful in elucidating their vaccine potential.

  11. Method to conjugate polysaccharide antigens to surfaces for the detection of antibodies.

    Science.gov (United States)

    Boas, Ulrik; Lind, Peter; Riber, Ulla

    2014-11-15

    A new generic method for the conjugation of lipopolysaccharide (LPS)-derived polysaccharide antigens from gram-negative bacteria has been developed using Salmonella as a model. After removal of lipid A from the LPS by mild acidolysis, the polysaccharide antigen was conjugated to polystyrene microbeads modified with N-alkyl hydroxylamine and N-alkyl-O-methyl hydroxylamine surface groups by incubation of antigen and beads for 16 h at 40 °C without the need for coupling agents. The efficiency of the new method was evaluated by flow cytometry in model samples and serum samples containing antibodies against Salmonella typhimurium and Salmonella dublin. The presented method was compared with a similar method for conjugation of Salmonella polysaccharide antigens to surfaces. Here, the new method showed higher antigen coupling efficiency by detecting low concentrations of antibodies. Furthermore, the polysaccharide-conjugated beads showed preserved bioactivity after 1 year of use. PMID:25076184

  12. Multiplex real-time PCR for identification of canine parvovirus antigenic types.

    Science.gov (United States)

    Kaur, Gurpreet; Chandra, Mudit; Dwivedi, P N; Narang, Deepti

    2016-07-01

    Canine parvovirus (CPV) is an important disease causing gastroenteritis and/or haemorrhagic gastroenteritis in dogs. There are four antigenic types of CPV reported worldwide viz. CPV 2, CPV 2a, CPV 2b and CPV 2c. The diagnosis of CPV with the identification of the antigen type responsible remains problematic. In the present study, identification as well as antigenic typing of CPV was done using a de novo multiplex real time PCR to combat the problem of antigenic type identification. From the study it could be concluded that the here developed multiplex real time PCR assay could be used for rapid detection of CPV as well as typing of its three antigenic types. PMID:26987970

  13. Association between HLA-DR1 and -DR3 antigens and unexplained repeated miscarriage

    DEFF Research Database (Denmark)

    Christiansen, O B; Ring, Mette; Rosgaard, A;

    1999-01-01

    antigens--other studies have been unable to demonstrate such associations. For the present meta-analysis, 18 cross-sectional or case-control studies (published or unpublished) reporting on frequencies of HLA-DR1 and -DR3 antigens among Caucasian women with unexplained repeated miscarriage were identified......Few, mostly small, studies have investigated the distribution of HLA class II antigens among women with unexplained recurrent miscarriage. Although some studies have reported statistically significant associations between this syndrome and certain HLA-DR antigens--especially the -DR1 and -DR3...... patients and because patients with only two miscarriages were included in many studies; this is defined as repeated miscarriage. The odds ratios of repeated miscarriage for the HLA-DR1 and -DR3 antigens were calculated for the individual studies and subsequently the pooled odds ratios for the studies were...

  14. Toward a network model of MHC class II-restricted antigen processing

    Directory of Open Access Journals (Sweden)

    Laurence C Eisenlohr

    2013-12-01

    Full Text Available The standard model of Major Histocompatibility Complex class II (MHCII-restricted antigen processing depicts a straightforward, linear pathway: Internalized antigens are converted into peptides that load in a chaperone dependent manner onto nascent MHCII in the late endosome, the complexes subsequently trafficking to the cell surface for recognition by CD4+ T cells (TCD4+. Several variations on this theme, both moderate and radical, have come to light but these alternatives have remained peripheral, the conventional pathway generally presumed to be the primary driver of TCD4+ responses. Here we continue to press for the conceptual repositioning of these alternatives toward the center while proposing that MHCII processing be thought of less in terms of discrete pathways and more in terms of a network whose major and minor conduits are variable depending upon many factors, including the epitope, the nature of the antigen, the source of the antigen, and the identity of the antigen-presenting cell.

  15. Evidence for horizontal gene transfer of two antigenically distinct O antigens in Bordetella bronchiseptica

    Science.gov (United States)

    Antigenic variation is one mechanism pathogens use to avoid immune-mediated competition between closely related strains. Here, we show that two Bordetella bronchiseptica strains, RB50 and 1289, express two antigenically distinct O-antigen serotypes (O1 and O2 respectively). When 18 additional B. b...

  16. Novel Functions for Glycosyltransferases Jhp0562 and GalT in Lewis Antigen Synthesis and Variation in Helicobacter pylori

    OpenAIRE

    Pohl, Mary Ann; Kienesberger, Sabine; Blaser, Martin J.

    2012-01-01

    Lewis (Le) antigens are fucosylated oligosaccharides present in the Helicobacter pylori lipopolysaccharide. Expression of these antigens is believed to be important for H. pylori colonization, since Le antigens also are expressed on the gastric epithelia in humans. A galactosyltransferase encoded by β-(1,3)galT is essential for production of type 1 (Lea and Leb) antigens. The upstream gene jhp0562, which is present in many but not all H. pylori strains, is homologous to β-(1,3)galT but is of ...

  17. Technical presentation

    CERN Document Server

    FP Department

    2009-01-01

    07 April 2009 Technical presentation by Leuze Electronics: 14.00 – 15.00, Main Building, Room 61-1-017 (Room A) Photoelectric sensors, data identification and transmission systems, image processing systems. We at Leuze Electronics are "the sensor people": we have been specialising in optoelectronic sensors and safety technology for accident prevention for over 40 years. Our dedicated staff are all highly customer oriented. Customers of Leuze Electronics can always rely on one thing – on us! •\tFounded in 1963 •\t740 employees •\t115 MEUR turnover •\t20 subsidiaries •\t3 production facilities in southern Germany Product groups: •\tPhotoelectric sensors •\tIdentification and measurements •\tSafety devices

  18. Cancer associated aberrant protein o-glycosylation can modify antigen processing and immune response

    DEFF Research Database (Denmark)

    Madsen, Caroline B; Petersen, Cecilie; Lavrsen, Kirstine;

    2012-01-01

    response to a cancer related tumor antigen, Balb/c or B6.Cg(CB)-Tg(HLA-A/H2-D)2Enge/J (HLA-A2 transgenic) mice were immunized with a non-glycosylated or GalNAc-glycosylated MUC1 derived peptide followed by comparison of T cell proliferation, IFN-¿ release, and antibody induction. Gal...... abolished MUC1 specific CD8+ T cell responses in HLA-A2 transgenic mice. GalNAc glycosylation of MUC1 antigen therefore facilitates uptake, MHC class II presentation, and antibody response but might block the antigen presentation to CD8+ T cells....

  19. Isolation and characterization of NIH 3T3 cells expressing polyomavirus small T antigen

    International Nuclear Information System (INIS)

    The polyomavirus small T-antigen gene, together with the polyomavirus promoter, was inserted into retrovirus vector pGV16 which contains the Moloney sarcoma virus long terminal repeat and neomycin resistance gene driven by the simian virus 40 promoter. This expression vector, pGVST, was packaged into retrovirus particles by transfection of PSI2 cells which harbor packaging-defective murine retrovirus genome. NIH 3T3 cells were infected by this replication-defective retrovirus containing pGVST. Of the 15 G418-resistant cell clones, 8 express small T antigen at various levels as revealed by immunoprecipitation. A cellular protein with an apparent molecular weight of about 32,000 coprecipitates with small T antigen. Immunofluorescent staining shows that small T antigen is mainly present in the nuclei. Morphologically, cells expressing small T antigen are indistinguishable from parental NIH 3T3 cells and have a microfilament pattern similar to that in parental NIH 3T3 cells. Cells expressing small T antigen form a flat monolayer but continue to grow beyond the saturation density observed for parental NIH 3T3 cells and eventually come off the culture plate as a result of overconfluency. There is some correlation between the level of expression of small T antigen and the growth rate of the cells. Small T-antigen-expressing cells form small colonies in soft agar. However, the proportion of cells which form these small colonies is rather small. A clone of these cells tested did not form tumors in nude mice within 3 months after inoculation of 106 cells per animal. Thus, present studies establish that the small T antigen of polyomavirus is a second nucleus-localized transforming gene product of the virus (the first one being large T antigen) and by itself has a function which is to stimulate the growth of NIH 3T3 cells beyond their saturation density in monolayer culture

  20. Diagnosis of tuberculosis based on the two specific antigens ESAT-6 and CFP10

    DEFF Research Database (Denmark)

    van Pinxteren, L A; Ravn, P; Agger, E M; Pollock, J; Andersen, P

    2000-01-01

    Tests based on tuberculin purified protein derivative (PPD) cannot distinguish between tuberculosis infection, Mycobacterium bovis BCG vaccination, or exposure to environmental mycobacteria. The present study investigated the diagnostic potential of two Mycobacterium tuberculosis-specific antigens...

  1. Monoclonal Antibody Production against Human Spermatozoal Surface Antigens

    Directory of Open Access Journals (Sweden)

    M Jedi-Tehrani

    2005-10-01

    Full Text Available Introduction: As monoclonal antibodies are potential tools for characterization of soluble or cellular surface antigens, use of these proteins has always been considered in infertility and reproduction research. Therefore, in this study, monoclonal antibodies against human sperm surface antigens were produced. Material and Methods: To produce specific clones against human sperm surface antigens, proteins were extracted using solubilization methods. Balb/c mice were immunized intraperitoneally with the proteins using complete Freund’s adjuvant in the first injection and incomplete Adjuvant in the following booster injections. Hybridoma cells producing ASA were cloned by limiting dilution. Results: Five stable ASA producing hybridoma clones were achieved and their antibody isotypes were determined by ELISA. All the isotypes were of IgG class. Their cross reactivity with rat and mice spermatozoa was examined but they did not have any cross reactivity. Conclusion: The produced antibodies can be used in further studies to characterize and evaluate each of the antigens present on human sperm surface and determining their role in fertilization.

  2. Evaluation of Intracellular Signaling Downstream Chimeric Antigen Receptors.

    Directory of Open Access Journals (Sweden)

    Hannah Karlsson

    Full Text Available CD19-targeting CAR T cells have shown potency in clinical trials targeting B cell leukemia. Although mainly second generation (2G CARs carrying CD28 or 4-1BB have been investigated in patients, preclinical studies suggest that third generation (3G CARs with both CD28 and 4-1BB have enhanced capacity. However, little is known about the intracellular signaling pathways downstream of CARs. In the present work, we have analyzed the signaling capacity post antigen stimulation in both 2G and 3G CARs. 3G CAR T cells expanded better than 2G CAR T cells upon repeated stimulation with IL-2 and autologous B cells. An antigen-driven accumulation of CAR+ cells was evident post antigen stimulation. The cytotoxicity of both 2G and 3G CAR T cells was maintained by repeated stimulation. The phosphorylation status of intracellular signaling proteins post antigen stimulation showed that 3G CAR T cells had a higher activation status than 2G. Several proteins involved in signaling downstream the TCR were activated, as were proteins involved in the cell cycle, cell adhesion and exocytosis. In conclusion, 3G CAR T cells had a higher degree of intracellular signaling activity than 2G CARs which may explain the increased proliferative capacity seen in 3G CAR T cells. The study also indicates that there may be other signaling pathways to consider when designing or evaluating new generations of CARs.

  3. Evaluation of Intracellular Signaling Downstream Chimeric Antigen Receptors.

    Science.gov (United States)

    Karlsson, Hannah; Svensson, Emma; Gigg, Camilla; Jarvius, Malin; Olsson-Strömberg, Ulla; Savoldo, Barbara; Dotti, Gianpietro; Loskog, Angelica

    2015-01-01

    CD19-targeting CAR T cells have shown potency in clinical trials targeting B cell leukemia. Although mainly second generation (2G) CARs carrying CD28 or 4-1BB have been investigated in patients, preclinical studies suggest that third generation (3G) CARs with both CD28 and 4-1BB have enhanced capacity. However, little is known about the intracellular signaling pathways downstream of CARs. In the present work, we have analyzed the signaling capacity post antigen stimulation in both 2G and 3G CARs. 3G CAR T cells expanded better than 2G CAR T cells upon repeated stimulation with IL-2 and autologous B cells. An antigen-driven accumulation of CAR+ cells was evident post antigen stimulation. The cytotoxicity of both 2G and 3G CAR T cells was maintained by repeated stimulation. The phosphorylation status of intracellular signaling proteins post antigen stimulation showed that 3G CAR T cells had a higher activation status than 2G. Several proteins involved in signaling downstream the TCR were activated, as were proteins involved in the cell cycle, cell adhesion and exocytosis. In conclusion, 3G CAR T cells had a higher degree of intracellular signaling activity than 2G CARs which may explain the increased proliferative capacity seen in 3G CAR T cells. The study also indicates that there may be other signaling pathways to consider when designing or evaluating new generations of CARs. PMID:26700307

  4. Antigenic typing of canine parvovirus using differential PCR.

    Science.gov (United States)

    Kaur, Gurpreet; Chandra, Mudit; Dwivedi, P N; Sharma, N S

    2014-12-01

    Canine parvovirus (CPV) is an enteric pathogen causing hemorrhagic enteritis in pups of 3-6 months of age and is mainly transmitted via feco-oral route. In the present study, a total of 85 animals rectal swabs suspected of CPV were tested using a PCR, nested PCR and a newly designed differential PCR. Using PCR 7 (8.23 %) animals were positive whereas 39 (45.88 %) were positive by using nested PCR and 40 (47.05 %) were positive for either one or more than one antigenic types of CPV using differential PCR. Using differential PCR it was found that CPV-2a and CPV-2b were the most prevailing antigenic types. Also it was found that dogs that were vaccinated too yielded positive CPV indicating a possible presence of additional CPV antigenic types. Thus, the primers used in differential PCR can be used in a single PCR reaction to detect various antigenic types of CPV. PMID:25674626

  5. Enhanced T cell responses to antigenic peptides targeted to B cell surface Ig, Ia, or class I molecules

    OpenAIRE

    1988-01-01

    The helper T cell recognition of soluble globular protein antigens requires that the proteins be processed by an APC, releasing a peptide that is transported to and held on the APC surface where it is recognized by the specific T cell in conjunction with Ia. When cellular processing functions are blocked, APC lose their ability to present native antigens while retaining the capacity to activate T cells when provided with a cognate peptide fragment that contains the T cell antigenic determinan...

  6. Comparative Study of rK39 Leishmania Antigen for Serodiagnosis of Visceral Leishmaniasis: Systematic Review with Meta-Analysis

    OpenAIRE

    Maia, Zuinara; Lírio, Monique; Mistro, Sóstenes; Mendes, Carlos Maurício Cardeal; Mehta, Sanjay R; Badaro, Roberto

    2012-01-01

    Background The rK39 recombinant protein is derived from a specific antigen produced by the Leishmania donovani complex, and has been used in the last two decades for the serodiagnosis of visceral leishmaniasis. We present here a systematic review and meta-analysis of studies evaluating serologic assays to diagnose visceral leishmaniasis to determine the accuracy of rK39 antigen in comparison to the use of other antigen preparations. Methodology/Principal Findings A systematic review with meta...

  7. CD28 and T cell antigen receptor signal transduction coordinately regulate interleukin 2 gene expression in response to superantigen stimulation

    OpenAIRE

    1992-01-01

    Activation of an immune response requires intercellular contact between T lymphocytes and antigen-presenting cells (APC). Interaction of the T cell antigen receptor (TCR) with antigen in the context of major histocompatibility molecules mediates signal transduction, but T cell activation appears to require the induction of a second costimulatory signal transduction pathway. Recent studies suggest that interaction of CD28 with B7 on APC might deliver such a costimulatory signal. To investigate...

  8. Lewis (y) Antigen Overexpression Increases the Expression of MMP-2 and MMP-9 and Invasion of Human Ovarian Cancer Cells

    OpenAIRE

    Shulan Zhang; Masao Iwamori; Changzhi Wang; Yifei Wang; Chuan Liu; Song Gao; Lili Gao; Bei Lin; Limei Yan

    2010-01-01

    Lewis (y) antigen is a difucosylated oligosaccharide present on the plasma membrane, and its overexpression is frequently found in human cancers and has been shown to be associated with poor prognosis. Our previous studies have shown that Lewis (y) antigen plays a positive role in the process of invasion and metastasis of ovarian cancer cells. However, the mechanisms by which Lewis (y) antigen enhances the invasion and tumor metastasis are still unknown. In this study, we established a stable...

  9. Protein coated microcrystals formulated with model antigens and modified with calcium phosphate exhibit enhanced phagocytosis and immunogenicity.

    Science.gov (United States)

    Jones, Sarah; Asokanathan, Catpagavalli; Kmiec, Dorota; Irvine, June; Fleck, Roland; Xing, Dorothy; Moore, Barry; Parton, Roger; Coote, John

    2014-07-16

    Protein-coated microcrystals (PCMCs) were investigated as potential vaccine formulations for a range of model antigens. Presentation of antigens as PCMCs increased the antigen-specific IgG responses for all antigens tested, compared to soluble antigens. When compared to conventional aluminium-adjuvanted formulations, PCMCs modified with calcium phosphate (CaP) showed enhanced antigen-specific IgG responses and a decreased antigen-specific IgG1:IgG2a ratio, indicating the induction of a more balanced Th1/Th2 response. The rate of antigen release from CaP PCMCs, in vitro, decreased strongly with increasing CaP loading but their immunogenicity in vivo was not significantly different, suggesting the adjuvanticity was not due to a depot effect. Notably, it was found that CaP modification enhanced the phagocytosis of fluorescent antigen-PCMC particles by J774.2 murine monocyte/macrophage cells compared to soluble antigen or soluble PCMCs. Thus, CaP PCMCs may provide an alternative to conventional aluminium-based acellular vaccines to provide a more balanced Th1/Th2 immune response. PMID:24120484

  10. Further characterization of filarial antigens by SDS polyacrylamide gel electrophoresis

    OpenAIRE

    Dissanayake, S.; Galahitiyawa, S. C.; Ismail, M. M.

    1983-01-01

    SDS (sodium dodecyl sulfate)-polyacrylamide gel electrophoresis of an antigen isolated from sera of Wuchereria bancrofti-infected patients and Setaria digitata antigen SD2-4 is reported. Both antigens showed carbohydrate (glycoprotein) staining. The W. bancrofti antigen had an apparent relative molecular mass of 35 000 while the S. digitata antigen SD2-4 migrated at the marker dye position on SDS-polyacrylamide gel electrophoresis. SDS treatment of these antigens did not abolish the precipita...

  11. Effects of Co60 gamma radiation on the immunogenic and antigenic properties of Bothrops jararacussu venom

    International Nuclear Information System (INIS)

    Ionizing radiation has been successfully employed to attenuate animals toxins and venoms for immunizing antisera producing animals. However, the radiation effects on antigenicity and immunogenecity have not yet been elucidated. In the present work, we investigated the effects of gamma rays on the antigenic and immunogenicity have not yet been elucidated. In the present work, we investigated the effects of gamma rays on the antigenic and immunogenic behaviour of Bothrops jararacussu venon. Venom samples (2mg/ml in 150 mM NaCl) were irradiated with 500, 1000 and 2000 Gy of 60 Co gamma rays. These samples were submitted to antigen capture ELISA on plates coated with commercial bothropic antiserum. Results suggest a loss of reactivity of the 1000 and 2000 Gy irradiated samples. Antibodies against native and 2000 Gy irradiated venoms were produced in rabbits. Both sera able to bind native venom with a slightly higher titer for anti-irradiated serum. These data suggest that radiation promoted structural modification on the antigen molecules. However since the antibodies produced against irradiated antivenom were able to recognize native venom, there must have been preservation of some antigenic determinants. It has already been demosntrated that irradiation of proteins leads to structural modifications and unfolding of the molecules. Our data suggest that irradiation led to conformational epitopes destruction with preservation of linear epitopes and that the response against irradiated venom may be attributed to these linear antigenic determinants. (author). 8 refs., 3 figs

  12. Cell Wall Anchoring of the Campylobacter Antigens to Lactococcus lactis.

    Science.gov (United States)

    Kobierecka, Patrycja A; Olech, Barbara; Książek, Monika; Derlatka, Katarzyna; Adamska, Iwona; Majewski, Paweł M; Jagusztyn-Krynicka, Elżbieta K; Wyszyńska, Agnieszka K

    2016-01-01

    Campylobacter jejuni is the most frequent cause of human food-borne gastroenteritis and chicken meat is the main source of infection. Recent studies showed that broiler chicken immunization against Campylobacter should be the most efficient way to lower the number of human infections by this pathogen. Induction of the mucosal immune system after oral antigen administration should provide protective immunity to chickens. In this work we tested the usefulness of Lactococcus lactis, the most extensively studied lactic acid bacterium, as a delivery vector for Campylobacter antigens. First we constructed hybrid protein - CjaA antigen presenting CjaD peptide epitopes on its surface. We showed that specific rabbit anti-rCjaAD serum reacted strongly with both CjaA and CjaD produced by a wild type C. jejuni strain. Next, rCjaAD and CjaA were fused to the C-terminus of the L. lactis YndF containing the LPTXG motif. The genes expressing these proteins were transcribed under control of the L. lactis Usp45 promoter and their products contain the Usp45 signal sequences. This strategy ensures a cell surface location of both analyzed proteins, which was confirmed by immunofluorescence assay. In order to evaluate the impact of antigen location on vaccine prototype efficacy, a L. lactis strain producing cytoplasm-located rCjaAD was also generated. Animal experiments showed a decrease of Campylobacter cecal load in vaccinated birds as compared with the control group and showed that the L. lactis harboring the surface-exposed rCjaAD antigen afforded greater protection than the L. lactis producing cytoplasm-located rCjaAD. To the best of our knowledge, this is the first attempt to employ Lactic Acid Bacteria (LAB) strains as a mucosal delivery vehicle for chicken immunization. Although the observed reduction of chicken colonization by Campylobacter resulting from vaccination was rather moderate, the experiments showed that LAB strains can be considered as an alternative vector to

  13. 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.

  14. A rapid radioimmunoassay for determination of tumor antigens with reference to carcinoembryonic antigen

    International Nuclear Information System (INIS)

    A novel experimental procedure for the determination of carcinoembryonic antigen (CEA) by a solid phase microradioimmunoassay has been developed. Goat anti-CEA antibodies were immobilized by coupling to cyanogen bromide activated filter paper discs. The inhibition of binding of radioiodinated CEA to the discs was proportional to the amount of unlabelled CEA present in the test sample. The experimental procedure involved two steps: (i) the test material containing unlabelled CEA was allowed to react with the antibody coated discs at 37 deg C for 2 hrs., and (ii) a standard amount of 125I-CEA was added to the reaction mixture and incubated for 24 hours at 37 deg C or room temperature. The discs were then washed 4 times and the radioactivity of each disc was determined. The sensitivity of the test in its present state of development was 2.5 ng/ml. (author)

  15. Incidence of Rh Antigens, Phenotype & Probable Genotype in the Population of Gwalior and Chambal Region, Central India

    OpenAIRE

    Sharma Dharmesh Chandra; Singhal Sachin; Rai Sunita; Iyenger Sudha; Sao Satya; Jain Bharat

    2013-01-01

    Introduction: Rhesus (Rh) antigen was discovered in 1940 by Karl Landsteiner and Wiener. In later years, because of its immunogenecity along with ABO grouping, RhD antigen testing was made mandatory before issuing a compatible blood. Presently there are five major antigens i.e. D, C, E, c and e in Rh blood group system. Aims: To know the distribution of major Rh antigens, its phenotype and most probable genotype in the population of Gwalior region i.e. Central India. Place a...

  16. The Ability of Immunoglobulin Yolk Recognized the Antigen in the Tissue of Ascaridia galli

    OpenAIRE

    Darmawi; U. Balqis; M. Hambal; R. Tiuria; B.P Priosoeryanto; E Handharyani

    2012-01-01

    Antigen-antibody reaction is an important tool for the analysis of localization of target molecules, including antigenic protein within worm tissues. The purpose of the present research was to demonstrate the ability of immunoglobulin yolk (IgY) anti-excretory/secretory recognized the antigen in the tissue of Ascaridia galli by mean of immunohistochemistry method. The excretory/secretory protein was procured from A. galli and concentrated by mean of vivaspin 30,000 MWCO. IgY was produced by e...

  17. Detection of Renibacterium salmoninarum antigen in migrating adult chum salmon (Oncorhynchus keta) in Japan.

    Science.gov (United States)

    Sakai, M; Atsuta, S; Kobayashi, M

    1992-01-01

    Renibacterium salmoninarum antigen was detected in the kidney of migrating chum salmon (Oncorhynchus keta) using the indirect dot blot assay and indirect fluorescent antibody test. The adult chum salmon had migrated into a bay in which cultured coho salmon infected with R. salmoninarum were present. Antigen was detected in 5% of the chum salmon although they did not have clinical signs of bacterial kidney disease (BKD). This report describes the first case of R. salmoninarum antigen detection among wild chum salmon populations in eastern Asia. PMID:1548789

  18. Barriers to antigenic escape by pathogens: trade-off between reproductive rate and antigenic mutability

    Directory of Open Access Journals (Sweden)

    Bush Robin M

    2007-11-01

    Full Text Available Abstract Background A single measles vaccination provides lifelong protection. No antigenic variants that escape immunity have been observed. By contrast, influenza continually evolves new antigenic variants, and the vaccine has to be updated frequently with new strains. Both measles and influenza are RNA viruses with high mutation rates, so the mutation rate alone cannot explain the differences in antigenic variability. Results We develop a new hypothesis to explain antigenic stasis versus change. We first note that the antigenically static viruses tend to have high reproductive rates and to concentrate infection in children, whereas antigenically variable viruses such as influenza tend to spread more widely across age classes. We argue that, for pathogens in a naive host population that spread more rapidly in younger individuals than in older individuals, natural selection weights more heavily a rise in reproductive rate. By contrast, pathogens that spread more readily among older individuals gain more by antigenic escape, so natural selection weights more heavily antigenic mutability. Conclusion These divergent selective pressures on reproductive rate and antigenic mutability may explain some of the observed differences between pathogens in age-class bias, reproductive rate, and antigenic variation.

  19. Cloning and characterization of Trypanosoma cruzi antigens bearing repetitive epitopes

    International Nuclear Information System (INIS)

    The genes of Trypanosoma cruzi, the causative agent of Chagas Disease, were cloned in the expression vector lambda gt11, and screened with a trypamastigote antiserum. Twelve clones expressing fusion proteins reacting to the antiserum were selected and further analysed in the western blot. One clone (7/2) expressing an antigen present in the cytoplasm of the parasite was found to react specifically with chagasic sera and may have potential as an immunodiagnostic reagent. (author). 11 refs, 4 figs

  20. The global antigenic diversity of swine influenza A viruses

    OpenAIRE

    Lewis, Nicola S.; Russell, Colin A.; Langat, Pinky; Tavis K Anderson; Berger, Kathryn; Bielejec, Filip; Burke, David F.; Dudas, Gytis; Fonville, Judith M; Fouchier, Ron AM; Kellam, Paul; Koel, Bjorn F; Lemey, Philippe; Nguyen, Tung; Nuansrichy, Bundit

    2016-01-01

    Swine influenza presents a substantial disease burden for pig populations worldwide and poses a potential pandemic threat to humans. There is considerable diversity in both H1 and H3 influenza viruses circulating in swine due to the frequent introductions of viruses from humans and birds coupled with geographic segregation of global swine populations. Much of this diversity is characterized genetically but the antigenic diversity of these viruses is poorly understood. Critically, the antigeni...

  1. Exosomes in the Thymus: Antigen Transfer and Vesicles

    OpenAIRE

    Skogberg, Gabriel; Telemo, Esbjörn; Ekwall, Olov

    2015-01-01

    Thymocytes go through several steps of maturation and selection in the thymus in order to form a functional pool of effector T-cells and regulatory T-cells in the periphery. Close interactions between thymocytes, thymic epithelial cells, and dendritic cells are of vital importance for the maturation, selection, and lineage decision of the thymocytes. One important question that is still unanswered is how a relatively small epithelial cell population can present a vast array of self-antigens t...

  2. Antigen-activated dendritic cells ameliorate influenza A infections

    OpenAIRE

    Boonnak, Kobporn; Vogel, Leatrice; Orandle, Marlene; Zimmerman, Daniel; Talor, Eyal; Subbarao, Kanta

    2013-01-01

    Influenza A viruses cause significant morbidity and mortality worldwide. There is a need for alternative or adjunct therapies, as resistance to currently used antiviral drugs is emerging rapidly. We tested ligand epitope antigen presentation system (LEAPS) technology as a new immune-based treatment for influenza virus infection in a mouse model. Influenza-J-LEAPS peptides were synthesized by conjugating the binding ligand derived from the β2-microglobulin chain of the human MHC class I molecu...

  3. Antigen Discovery: a Postgenomic Approach to Leprosy Diagnosis

    OpenAIRE

    Aráoz, Romulo; Honoré, Nadine; Cho, Sungae; Kim, Jong-Pill; Cho, Sang-Nae; Monot, Marc; Demangel, Caroline; Brennan, Patrick J.; Cole, Stewart T.

    2006-01-01

    Leprosy is an infectious, neurodegenerative disease of humans caused by Mycobacterium leprae. Despite effective control programs, the incidence of leprosy remains stubbornly high, suggesting that transmission may be more common than expected. The rationale of this work was to use bioinformatics and comparative genomics to identify potentially antigenic proteins for diagnostic purposes. This approach defined three classes of proteins: those restricted to M. leprae (class I), those present in M...

  4. Multiple joint tuberculosis presenting as HLA-B27 disease

    OpenAIRE

    Hopkins, G. O.

    1983-01-01

    A case of multifocal osteoarticular tuberculosis in a young Caucasian male is presented. The diagnostic difficulty, compounded by slow progression of the disorder and the presence of the tissue antigen HLA-B27, is discussed.

  5. Antigens linked to synthetic microspheres induce immune responses in primates in the absence of adjuvant.

    Science.gov (United States)

    Sedlik, C; Perraut, R; Bonnemains, B; Leclerc, C

    1996-01-01

    Although most strategies of vaccination require immunopotentiation to induce efficient immune responses, the development of new adjuvants for human vaccines is highly limited by safety problems. In order to overcome this problem, we developed a new vaccine formulation based on the covalent linkage of protein or peptide to synthetic microspheres. In previous experiments performed in mice, we demonstrated that these particulate antigens induce strong antigen-specific CD4+ T cell proliferative responses in the absence of adjuvant. In the present study, we analyzed the immunogenicity in primate Saimiri sciureus monkeys of two different proteins linked to synthetic microspheres. Immune responses induced by these particulate proteins administered without adjuvant were compared to those stimulated by the soluble antigens injected with alum. We currently demonstrated that, in monkeys, particulate antigens administered without adjuvant, induced good PBMC proliferative response and antibody production. Furthermore, the analysis of antibody responses using mAbs specific for different Saimiri sciureus immunoglobulins showed that the antibody response profiles were different in monkeys immunized with soluble versus particulate form of antigens. Results of this study demonstrate that particulate form of antigen may stimulate qualitatively different immune responses as compared to alum and therefore suggest that this new antigen formulation could be an attractive candidate for the development of vaccines. PMID:8852604

  6. Biological function and molecular mapping of M antigen in yeast phase of Histoplasma capsulatum.

    Directory of Open Access Journals (Sweden)

    Allan Jefferson Guimarães

    Full Text Available Histoplasmosis, due to the intracellular fungus Histoplasma capsulatum, can be diagnosed by demonstrating the presence of antibodies specific to the immunodominant M antigen. However, the role of this protein in the pathogenesis of histoplasmosis has not been elucidated. We sought to structurally and immunologically characterize the protein, determine yeast cell surface expression, and confirm catalase activity. A 3D-rendering of the M antigen by homology modeling revealed that the structures and domains closely resemble characterized fungal catalases. We generated monoclonal antibodies (mAbs to the protein and determined that the M antigen is present on the yeast cell surface and in cell wall/cell membrane preparations. Similarly, we found that the majority of catalase activity was in extracts containing fungal surface antigens and that the M antigen is not significantly secreted by live yeast cells. The mAbs also identified unique epitopes on the M antigen. The localization of the M antigen to the cell surface of H. capsulatum yeast and the characterization of the protein's major epitopes have important implications since it demonstrates that although the protein may participate in protecting the fungus against oxidative stress it is also accessible to host immune cells and antibody.

  7. Expression and immunogenicity of novel subunit enterovirus 71 VP1 antigens

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Juan [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Microbiology and Immunology, Nanjing Medical University (China); Wang, Shixia [China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Medicine, University of Massachusetts Medical School (United States); Gan, Weihua [Department of Pediatrics, The Second Affiliated Hospital, Nanjing Medical University (China); Zhang, Wenhong [Department of Infectious Diseases, Huashan Hospital, Fudan University (China); Ju, Liwen [School of Public Health, Fudan University (China); Huang, Zuhu [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China); China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Lu, Shan, E-mail: shan.lu@umassmed.edu [Department of Infectious Diseases, The First Affiliated Hospital, Nanjing Medical University (China); China-US Vaccine Research Center, The First Affiliated Hospital, Nanjing Medical University (China); Department of Medicine, University of Massachusetts Medical School (United States)

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer EV71 is a major emerging infectious disease in many Asian countries. Black-Right-Pointing-Pointer Inactivated EV71 vaccines are in clinical studies but their safety and efficacy are unknown. Black-Right-Pointing-Pointer Developing subunit based EV71 vaccines is significant and novel antigen design is needed. Black-Right-Pointing-Pointer DNA immunization is an efficient tool to test the immunogenicity of VP1 based EV71 vaccines. Black-Right-Pointing-Pointer Multiple VP1 antigens are developed showing immunogenic potential. -- Abstract: Hand, foot, and mouth disease (HFMD) is a common viral illness in young children. HFMD is caused by viruses belonging to the enterovirus genus of the picornavirus family. Recently, enterovirus 71 (EV71) has emerged as a virulent agent for HFMD with severe clinical outcomes. In the current report, we conducted a pilot antigen engineering study to optimize the expression and immunogenicity of subunit VP1 antigen for the design of EV71 vaccines. DNA immunization was adopted as a simple technical approach to test different designs of VP1 antigens without the need to express VP1 protein in vitro first. Our studies indicated that the expression and immunogenicity of VP1 protein can be improved with alternated VP1 antigen designs. Data presented in the current report revealed novel pathways to optimize the design of VP1 antigen-based EV71 vaccines.

  8. Expression and immunogenicity of novel subunit enterovirus 71 VP1 antigens

    International Nuclear Information System (INIS)

    Highlights: ► EV71 is a major emerging infectious disease in many Asian countries. ► Inactivated EV71 vaccines are in clinical studies but their safety and efficacy are unknown. ► Developing subunit based EV71 vaccines is significant and novel antigen design is needed. ► DNA immunization is an efficient tool to test the immunogenicity of VP1 based EV71 vaccines. ► Multiple VP1 antigens are developed showing immunogenic potential. -- Abstract: Hand, foot, and mouth disease (HFMD) is a common viral illness in young children. HFMD is caused by viruses belonging to the enterovirus genus of the picornavirus family. Recently, enterovirus 71 (EV71) has emerged as a virulent agent for HFMD with severe clinical outcomes. In the current report, we conducted a pilot antigen engineering study to optimize the expression and immunogenicity of subunit VP1 antigen for the design of EV71 vaccines. DNA immunization was adopted as a simple technical approach to test different designs of VP1 antigens without the need to express VP1 protein in vitro first. Our studies indicated that the expression and immunogenicity of VP1 protein can be improved with alternated VP1 antigen designs. Data presented in the current report revealed novel pathways to optimize the design of VP1 antigen-based EV71 vaccines.

  9. Comparative Evaluation of Native Antigens for the Development of Brucellosis Antibody Detection System

    Directory of Open Access Journals (Sweden)

    Yasmin Bano

    2015-09-01

    Full Text Available Brucellosis is a highly infectious zoonotic disease and an economically important infection of humans and livestock with a worldwide distribution. The main mode of transmission of this disease to humans is through the consumption of infected milk, milk products, and uncooked or raw meat. The present study was designed to prepare few native antigens, that is, sonicated antigen (SA, cell envelope (CE antigen, and freeze and thaw (FT antigen from Brucella abortus S99 culture and to test them in a highly sensitive and specific indirect enzyme-linked immunosorbent assay (I-ELISA in both a microtiter plate and a dot-blot format for the development of field-based diagnosis. All 50 suspected bovine samples were tested by plate as well as in dot ELISA formats for all the three antigens prepared. The CE antigen was found to be more suitable as it had the maximum agreement with the Rose Bengal plate agglutination test results followed by the SA and the least agreement was found with that of the FT antigen. This detection system in microtiter plates and a dot-blot format will be useful for the rapid screening of samples for the disease surveillance and routine diagnosis.

  10. Mapping Epitopes on a Protein Antigen by the Proteolysis of Antigen-Antibody Complexes

    Science.gov (United States)

    Jemmerson, Ronald; Paterson, Yvonne

    1986-05-01

    A monoclonal antibody bound to a protein antigen decreases the rate of proteolytic cleavage of the antigen, having the greatest effect on those regions involved in antibody contact. Thus, an epitope can be identified by the ability of the antibody to protect one region of the antigen more than others from proteolysis. By means of this approach, two distinct epitopes, both conformationally well-ordered, were characterized on horse cytochrome c.

  11. A Novel Treponema pallidum Antigen, TP0136, Is an Outer Membrane Protein That Binds Human Fibronectin▿

    OpenAIRE

    Brinkman, Mary Beth; McGill, Melanie A.; Pettersson, Jonas; Rogers, Arthur; Matějková, Petra; Šmajs, David; Weinstock, George M.; Norris, Steven J; Palzkill, Timothy

    2008-01-01

    The antigenicity, structural location, and function of the predicted lipoprotein TP0136 of Treponema pallidum subsp. pallidum were investigated based on previous screening studies indicating that anti-TP0136 antibodies are present in the sera of syphilis patients and experimentally infected rabbits. Recombinant TP0136 (rTP0136) protein was purified and shown to be strongly antigenic during human and experimental rabbit infection. The TP0136 protein was exposed on the surface of the bacterial ...

  12. Production of Single-Chain Variable-Fragments against Carbohydrate Antigens

    OpenAIRE

    Yoko Fujita-Yamaguchi

    2014-01-01

    The production of human single-chain variable-fragments (scFvs) against carbohydrate antigens by phage display technology is seemingly a logical strategy towards the development of antibody therapeutics, since carbohydrates are self-antigens. Panning and screening of phages displaying human scFvs using a variety of neoglycolipids presenting structurally-defined carbohydrates resulted in a number of candidate phage clones as judged by cautious evaluation of DNA sequences and specific binding t...

  13. Nanodelci: sodobni dostavni sistem za učinkovine in antigene celicam imunskega sistema:

    OpenAIRE

    Kos, Janko; Kristl, Julijana; Obermajer, Nataša

    2007-01-01

    As the immune cells are distributed in bodily fluids and tissues throughout the organism, they represent a moving target for drug delivery. In this case aclassical approach applying high doses of the drug is not appropriate and, therefore, the use of nanoparticles represents a good alternative to avoid, orat least decrease its side effects and increase efficacy. Nanoparticles can be used as an efficient delivery system to enhance the uptake of antigens by antigen presenting cells as well as t...

  14. 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...

  15. STANDARDIZATION OF PROCEDURES OF Plasmodium falciparum ANTIGEN PREPARATION FOR SEROLOGIC TESTS

    OpenAIRE

    Sandra L.M. AVILA; Tania R. TOZETTO-MENDOZA; ARRUK Viviana G.; Ferreira, Antonio Walter

    1998-01-01

    The objective of the present study is to standardize the technical variables for preparation and storage of Plasmodium falciparum and of antigen components extracted with the amphoteric detergent Zwittergent. P. falciparum obtained from in vitro culture was stored at different temperatures and for different periods of time. For each variable, antigen components of the parasite were extracted in the presence or absence of protease inhibitors and submitted or not to later dialysis. Products wer...

  16. Scaffolded Antigens in Yeast Cell Particle Vaccines Provide Protection against Systemic Polyoma Virus Infection

    OpenAIRE

    Tipper, Donald J.; Szomolanyi-Tsuda, Eva

    2016-01-01

    Background. U65, a self-aggregating peptide scaffold, traps fused protein antigens in yeast cells. Conversion to Yeast Cell Particle (YCP) vaccines by partial removal of surface mannoproteins exposes β-glucan, mediating efficient uptake by antigen-presenting cells (APCs). YCP vaccines are inexpensive, capable of rapid large-scale production and have potential for both parenteral and oral use. Results. YCP processing by alkaline hydrolysis exposes up to 20% of the glucan but converts scaffolde...

  17. Modification of the lipid moiety of the enterobacterial common antigen by the "Pseudomonas factor".

    OpenAIRE

    Kuhn, H M; Neter, E; Mayer, H

    1983-01-01

    Pseudomonas aeruginosa produces a factor (PF) which affects the enterobacterial common antigen (ECA); resulting in failure of the antigen to modify erythrocytes for hemagglutination by ECA antibodies. In the present study the nature of PF was determined. Pronase treatment abolished its activity, indicating the protein nature of PF. PF-treated ECA no longer coated erythrocytes but still reacted with ECA antibodies in immunoelectrophoresis tests with monospecific antiserum to ECA, although diff...

  18. PREDICTION OF ANTIGENIC AND BINDING SITES OF NEUROTOXIN 23 OF SCORPION (LYCHASMUCRONACTUS SP.)

    OpenAIRE

    Bharati K Thosare; Ingale, Arun G

    2015-01-01

    Identification of antigenic and binding site of protein is highly desirable for the design of vaccines and immunodiagnostics. The present exercise deals with a prediction of antigenic as well as binding sites of neurotoxin 23 of Lychasmucronactus. This species of scorpion having diverse molecules of toxic peptide, the peptide neurotoxin 23 is 96 amino acids long of which 23 to 96 specifically code for neurotoxin. The total of 27 such different ligand binding residue were identifie...

  19. Tales of Antigen Evasion from CAR Therapy.

    Science.gov (United States)

    Sadelain, Michel

    2016-06-01

    Both T cells bearing chimeric antigen receptors and tumor-specific antibodies can successfully target some malignancies, but antigen escape can lead to relapse. Two articles in this issue of Cancer Immunology Research explore what effective countermeasures may prevent it. Cancer Immunol Res; 4(6); 473-473. ©2016 AACRSee articles by Zah et al., p. 498, and Rufener et al., p. 509. PMID:27252092

  20. Characterization of an antigenically distinct porcine rotavirus.

    OpenAIRE

    Bridger, J C; Clarke, I. N.; McCrae, M A

    1982-01-01

    A porcine virus with rotavirus morphology, which was antigenically unrelated to previously described rotaviruses, is described. Particles with an outer capsid layer measured 75 nm and those lacking the outer layer were 63 nm in diameter. Particles which resembled cores were also identified. The virus was shown to be antigenically distinct from other rotaviruses as judged by immunofluorescence and immune electron microscopy, and it failed to protect piglets from challenge with porcine rotaviru...

  1. Antigenic variation in vector-borne pathogens.

    OpenAIRE

    Barbour, A. G.; Restrepo, B I

    2000-01-01

    Several pathogens of humans and domestic animals depend on hematophagous arthropods to transmit them from one vertebrate reservoir host to another and maintain them in an environment. These pathogens use antigenic variation to prolong their circulation in the blood and thus increase the likelihood of transmission. By convergent evolution, bacterial and protozoal vector-borne pathogens have acquired similar genetic mechanisms for successful antigenic variation. Borrelia spp. and Anaplasma marg...

  2. Reverse immunoediting: When immunity is edited by antigen.

    Science.gov (United States)

    Merlo, Anna; Santa, Silvia Dalla; Dolcetti, Riccardo; Zanovello, Paola; Rosato, Antonio

    2016-07-01

    Immune selective pressure occurring during cancer immunoediting shapes tumor features revealed at clinical presentation. However, in the "Escape" phase, the tumor itself has the chance to influence the immunological response. Therefore, the capacity of the immune response to sculpt the tumor characteristics is only one side of the coin and even the opposite is likely true, i.e. that an antigen can shape the immune response in a sort of "reverse immunoediting". This reciprocal modeling probably occurs continuously, whenever the immune system encounters a tumor/foreign antigen, and can be operative in the pathogen/immune system interplay, thus possibly permeating the protective immunity as a whole. In line with this view, the characterization of a T cell response as well as the design of both active and passive immunotherapy strategies should also take into account all Ag features (type, load and presentation). Overall, we suggest that the "reverse immunoediting" hypothesis could help to dissect the complex interplay between antigens and the immune repertoire, and to improve the outcome of immunotherapeutic approaches, where T cell responses are manipulated and reprogrammed. PMID:27131431

  3. Rabies virus glycoprotein as a carrier for anthrax protective antigen

    International Nuclear Information System (INIS)

    Live viral vectors expressing foreign antigens have shown great promise as vaccines against viral diseases. However, safety concerns remain a major problem regarding the use of even highly attenuated viral vectors. Using the rabies virus (RV) envelope protein as a carrier molecule, we show here that inactivated RV particles can be utilized to present Bacillus anthracis protective antigen (PA) domain-4 in the viral membrane. In addition to the RV glycoprotein (G) transmembrane and cytoplasmic domains, a portion of the RV G ectodomain was required to express the chimeric RV G anthrax PA on the cell surface. The novel antigen was also efficiently incorporated into RV virions. Mice immunized with the inactivated recombinant RV virions exhibited seroconversion against both RV G and anthrax PA, and a second inoculation greatly increased these responses. These data demonstrate that a viral envelope protein can carry a bacterial protein and that a viral carrier can display whole polypeptides compared to the limited epitope presentation of previous viral systems

  4. Antigen specificity can be irrelevant to immunocytokine efficacy and biodistribution.

    Science.gov (United States)

    Tzeng, Alice; Kwan, Byron H; Opel, Cary F; Navaratna, Tejas; Wittrup, K Dane

    2015-03-17

    Cytokine therapy can activate potent, sustained antitumor responses, but collateral toxicity often limits dosages. Although antibody-cytokine fusions (immunocytokines) have been designed with the intent to localize cytokine activity, systemic dose-limiting side effects are not fully ameliorated by attempted tumor targeting. Using the s.c. B16F10 melanoma model, we found that a nontoxic dose of IL-2 immunocytokine synergized with tumor-specific antibody to significantly enhance therapeutic outcomes compared with immunocytokine monotherapy, concomitant with increased tumor saturation and intratumoral cytokine responses. Examination of cell subset biodistribution showed that the immunocytokine associated mainly with IL-2R-expressing innate immune cells, with more bound immunocytokine present in systemic organs than the tumor microenvironment. More surprisingly, immunocytokine antigen specificity and Fcγ receptor interactions did not seem necessary for therapeutic efficacy or biodistribution patterns because immunocytokines with irrelevant specificity and/or inactive mutant Fc domains behaved similarly to tumor-specific immunocytokine. IL-2-IL-2R interactions, rather than antibody-antigen targeting, dictated immunocytokine localization; however, the lack of tumor targeting did not preclude successful antibody combination therapy. Mathematical modeling revealed immunocytokine size as another driver of antigen targeting efficiency. This work presents a safe, straightforward strategy for augmenting immunocytokine efficacy by supplementary antibody dosing and explores underappreciated factors that can subvert efforts to purposefully alter cytokine biodistribution. PMID:25733854

  5. IPNV Antigen Uptake and Distribution in Atlantic Salmon Following Oral Administration

    Directory of Open Access Journals (Sweden)

    Lihan Chen

    2015-05-01

    Full Text Available One impediment to the successful oral vaccination in fish is the hostile stomach environment that antigens must cross. Furthermore, uptake of antigens from the gut to systemic distribution is required for induction of systemic immunity, the dynamics of which are poorly understood. In the present study, groups of Atlantic salmon parr were intubated with live or inactivated infectious pancreatic necrosis virus (IPNV, either orally or anally. At 1, 24 and 72 h post infection (p.i., the fish were sacrificed. Serum was used for assessing IPNV by ELISA, while formalin-fixed head-kidney, spleen, liver and intestine tissues were used for the demonstration of antigens by immunohistochemistry. Both live and inactivated IPNV antigens were observed in enterocytes of the intestines and in immune cells of the head-kidneys and spleens of all groups. In the liver, no antigens were observed in any of the groups. Significantly higher serum antigen OD values (p < 0.04 were observed in orally- compared to anally-intubated fish. By contrast, no difference (p = 0.05 was observed in tissue antigens between these groups by immunohistochemistry. No significant difference (p = 0.05 in serum antigens was observed between groups intubated with live and inactivated IPNV, while in tissues, significantly more antigens (p < 0.03 were observe in the latter compared to the former. These findings demonstrate that both live and inactivated IPNV are taken up by enterocytes in the intestines of Atlantic salmon, likely by receptor-mediated mechanisms. Higher IPNV uptake by the oral compared to anal route suggests that both the anterior and posterior intestines are important for the uptake of the virus and that IPNV is resistant to gastric degradation of the Atlantic salmon stomach.

  6. Proliferating cell nuclear antigen in neutrophil fate.

    Science.gov (United States)

    Witko-Sarsat, Véronique; Ohayon, Delphine

    2016-09-01

    The life span of a neutrophil is a tightly regulated process as extended survival is beneficial for pathogen elimination and cell death necessary to prevent cytotoxic content release from activated neutrophils at the inflammatory site. Therefore, the control between survival and death must be a dynamic process. We have previously described that proliferating cell nuclear antigen (PCNA) which is known as a nuclear protein pivotal in DNA synthesis, is a key element in controlling neutrophil survival through its association with procaspases. Contrary to the dogma which asserted that PCNA has a strictly nuclear function, in mature neutrophils, PCNA is present exclusively within the cytosol due to its nuclear export at the end of the granulocytic differentiation. More recent studies are consistent with the notion that the cytosolic scaffold of PCNA is aimed at modulating neutrophil fate rather than simply preventing death. Ultimately, targeting neutrophil survival might have important applications not just in the field of immunology and inflammation, but also in hematology and transfusion. The neutrophil emerges as a unique and powerful cellular model to unravel the basic mechanisms governing the cell cycle-independent functions of PCNA and should be considered as a leader of the pack. PMID:27558345

  7. Antigenic scheme for Citrobacter koseri (syn. C. diversus, Levinea malonatica); three new antigens recognized in strains from Israel.

    OpenAIRE

    Gross, R. J.; Rowe, B; Sechter, I; Cahan, D.; Altman, G.

    1981-01-01

    An antigenic scheme for Citrobacter koseri was described previously and consisted of 14 'O' antigens. Three additional antigens are now added to the scheme and type strains for these antigens are designated. Their origins and their biochemical and serological reactions are described.

  8. Synthesis and identification of the artificial antigen for DiHT in irradiation food

    International Nuclear Information System (INIS)

    In the present study, 5, 6-Dihydrothymidine Hapten (DiHT-COOH) was synthesized by using 5, 6-Dihydrothymidine (DiHT) as raw material. DiHT-COOH was identified by thin layer chromatography and 1H-NMR. Hapten was conjugated to bovine serum albumin (BSA) and ovalbumin (OVA) to obtain artificial immune antigen and coating antigen, respectively. After detected by UV spectroscopy and SDS-PAGE, the ratios of Hapten to protein were calculated. The conjugation ratios of immunogen and coating antigen were 9.8 : 1 and 12 : 1, respectively. Antisera were obtained by immunizing BALB/c with immunogen and the titer were 1 : 2.56 × 104, which indicated the synthesis of artificial antigen was successful. (authors)

  9. Design, automated synthesis and immunological evaluation of NOD2-ligand–antigen conjugates

    Directory of Open Access Journals (Sweden)

    Marian M. J. H. P. Willems

    2014-06-01

    Full Text Available The covalent attachment of an innate immune system stimulating agent to an antigen can provide active vaccine modalities capable of eliciting a potent immune response against the incorporated antigen. Here we describe the design, automated synthesis and immunological evaluation of a set of four muramyl dipeptide–peptide antigen conjugates. Muramyl dipeptide (MDP represents a well-known ligand for the intracellular NOD2 receptor and our study shows that covalently linking an MDP-moiety to an antigenic peptide can lead to a construct that is capable of stimulating the NOD2 receptor if the ligand is attached at the anomeric center of the muramic acid. The constructs can be processed by dendritic cells (DCs and the conjugation does not adversely affect the presentation of the incorporated SIINFEKL epitope on MHC-I molecules. However, stimulation of the NOD2 receptor in DCs was not sufficient to provide a strong immunostimulatory signal.

  10. A simple and safe method for single HLA-antigen-typing by a solid phase assay.

    Science.gov (United States)

    Häcker-Shahin, B; Giannitsis, D J

    1991-01-01

    A rapid solid phase assay for detection of single HLA-antigens on platelets was developed. The platelets were attached to the surface of polystyrene microtitre plate wells by means of a sodium carbonate buffer and centrifugation. Uncovered areas were blocked by a gelatin blocking buffer. After incubation with commercially available anti-HLA-sera the bound anti-HLA-specific antibodies directed against HLA-antigens present on the platelets were made visible by anti-IgG-coated indicator red cells and a brief centrifugation. A positive result, meaning the presence of an HLA-antigen, was indicated by a slight red cell adherence over the reaction surface. In the absence of the HLA-antigen no binding occurred and the indicator red cells formed a small red disc-like pellet. PMID:1954783

  11. Screening and analysis of hepatocellular carcinomaassociated antigens and their encoding genes

    Institute of Scientific and Technical Information of China (English)

    SHI Yongyu; WANG Hongcheng; LI Yan; PANG Xuewen; SUN Wensheng; CHEN Weifeng

    2003-01-01

    Identification of hepatocellular carcinoma- associated tumor antigens is necessary and pivotal for specific immunotherapy in hepatocellular carcinoma (HCC) patients. In the present study, HCC cDNAs are constructed into ZAP cDNA expression library and screened by sera of patients with HCC. The positive clones are DNA sequenced and analyzed by bioinformatics. Thirty-one genes of hepatocellular carcinoma-associated tumor antigens are identified, of which 1 is unknown and 30 are known. The proteins encoded by these known genes can be classified into 8 categories: constitutive molecules of hepatocytes, RNA transcription and splicing-associated molecules, protein metabolism-associated molecules, energy synthesis-associated molecules, signal transduction molecules, cell adhesion molecules, immunosuppressive molecules, and proteins with unknown function. Among these genes, CAGE is a cancer-testis (CT) antigen. It is concluded that identification of hepatocellular carcinoma-associated tumor antigens provides potential targets for immunotherapy of HCC patients and facilitates explanation of carcinogenesis of HCC.

  12. Comparison of melanoma antigens in whole tumor vaccine to those from IIB-MEL-J cells.

    Science.gov (United States)

    McGee, J M; Patten, M R; Malnar, K F; Price, J A; Mayes, J S; Watson, G H

    1999-06-01

    Immunotherapy for melanoma shows promise. Our previous whole tumor (WT) vaccine was noted to have positive clinical effects. We have now developed a new, safer melanoma vaccine that is derived from IIB-MEL-J tissue culture (TC) cells. In this study, we compare by Western blot analyses the antigens in the WT vaccine to antigens in the TC vaccine. Sera from 12 WT vaccine recipients, 8 melanoma patients who received no immunotherapy, and 8 controls served as a source of antibodies to investigate potential antigens in the vaccines. Three major antigenic peptides with approximate molecular weighs of 46, 40, and 36 kDA were present in both vaccines, while two other antigenic peptides with approximate molecular weighs of 68 and 48 kDA were present only in the TC vaccine. The reaction was similar between the patients who received the WT vaccine and those who did not receive the vaccine. Some of the individuals who did not have melanoma showed some reaction, but not to the extent of the melanoma patients. The intensity of immunostaining was greater for the TC vaccine when compared to the WT vaccine, indicating that these proteins are in a higher concentration in the TC vaccine. This new vaccine from IIB-MEL-J tissue culture cells provides a higher yield and a much more consistent source of potentially clinically relevant antigens without risk of infection or contamination by other irrelevant materials. PMID:10850304

  13. Assembly and Immunological Processing of Polyelectrolyte Multilayers Composed of Antigens and Adjuvants

    Science.gov (United States)

    2016-01-01

    While biomaterials provide a platform to control the delivery of vaccines, the recently discovered intrinsic inflammatory characteristics of many polymeric carriers can also complicate rational design because the carrier itself can alter the response to other vaccine components. To address this challenge, we recently developed immune-polyelectrolyte multilayer (iPEMs) capsules electrostatically assembled entirely from peptide antigen and molecular adjuvants. Here, we use iPEMs built from SIINFEKL model antigen and polyIC, a stimulatory toll-like receptor agonist, to investigate the impact of pH on iPEM assembly, the processing and interactions of each iPEM component with primary immune cells, and the role of these interactions during antigen-specific T cell responses in coculture and mice. We discovered that iPEM assembly is pH dependent with respect to both the antigen and adjuvant component. Controlling the pH also allows tuning of the relative loading of SIINFEKL and polyIC in iPEM capsules. During in vitro studies with primary dendritic cells (DCs), iPEM capsules ensure that greater than 95% of cells containing at least one signal (i.e., antigen, adjuvant) also contained the other signal. This codelivery leads to DC maturation and SIINFEKL presentation via the MHC-I antigen presentation pathway, resulting in antigen-specific T cell proliferation and pro-inflammatory cytokine secretion. In mice, iPEM capsules potently expand antigen-specific T cells compared with equivalent admixed formulations. Of note, these enhancements become more pronounced with successive booster injections, suggesting that iPEMs functionally improve memory recall response. Together our results reveal some of the features that can be tuned to modulate the properties of iPEM capsules, and how these modular vaccine structures can be used to enhance interactions with immune cells in vitro and in mice. PMID:27380137

  14. Current opinion on human leukocyte antigen-G in China

    Institute of Scientific and Technical Information of China (English)

    YAN Wei-hua; LIN Ai-fen

    2007-01-01

    @@ Since discovery and cloning of the non-classical human leukocyte antigen (HLA) class Ⅰ antigen HLA-G by Geraghty et al1 in 1987, a large number of studies have been carried out. HLA-G has a low polymorphism, limited distribution to normal tissues and seven isoforms resulting from its primary mRNA alternative splicing.2 HLA-G expression was first found on the extravillous cytotrophoblasts, at the fetal-maternal interface during normal pregnancy, which lacks the expression of HLA-A, -B and HLA Ⅱ antigens. Initial studies on HLA-G mainly addressed its function in fetal-maternal immunotolerance.3 Two decades later,HLA-G is now considered to be a very important immune molecule which plays a vital immune inhibitory role in the context of reproduction, oncology, transplantation,infection and also in autoimmune disease.4 A number of Chinese research teams are interested in, and have contributed to, the publication of more than 80 peer-reviewed articles and reviews on HLA-G over the past ten years. We summarize the key points in this field that were presented and discussed by them.

  15. Proteomic analysis of antigens from Leishmania infantum promastigotes.

    Science.gov (United States)

    Dea-Ayuela, María Auxiliadora; Rama-Iñiguez, Sara; Bolás-Fernández, Francisco

    2006-07-01

    Leishmaniasis is a zoonotic disease caused by the species of the genus Leishmania, flagellated protozoa that multiply inside mammalian macrophages and are transmitted by the bite of the sandfly. The disease is widespread and due to the lack of fully effective treatment and vaccination the search for new drugs and immune targets is needed. Proteomics seems to be a suitable strategy because the annotated sequenced genome of L. major is available. Here, we present a high-resolution proteome for L. infantum promastigotes comprising of around 700 spots. Western blot with rabbit hyperimmune serum raised against L. infantum promastiogote extracts and further analysis by MALDI-TOF and MALDI-TOF/TOF MS allowed the identification of various relevant functional antigenic proteins. Major antigenic proteins were identified as propionil carboxilasa, ATPase beta subunit, transketolase, proteasome subunit, succinyl-diaminopimelate desuccinylase, a probable tubulin alpha chain, the full-size heat shock protein 70, and several proteins of unknown function. In addition, one enzyme from the ergosterol biosynthesis pathway (adrenodoxin reductase) and the structural paraflagellar rod protein 3 (PAR3) were found among non-antigenic proteins. This study corroborates the usefulness of proteomics in identifying new proteins with crucial biological functions in Leishmania parasites. PMID:16791830

  16. Langerhans Cell Histiocytosis Presenting as Uncontrolled Asthma

    OpenAIRE

    Rawlins, Frederic A.; Hull, James E.; Morgan, Julia A.; Morris, Michael J.

    2013-01-01

    Langerhans cell histiocytosis (LCH) is an uncommon disorder affecting primarily young adult smokers. It is characterized by abnormal proliferation of Langerhans cells, specialized monocyte-macrophage lineage antigen-presenting cells. LCH can affect the lungs in isolation or as part of a systemic disease. Most commonly, the disease presents in the third or fourth decade without gender predominance. Symptoms typically include dyspnea and cough. Commonly, physical examination is unremarkable but...

  17. Beyond antigens and adjuvants: formulating future vaccines.

    Science.gov (United States)

    Moyer, Tyson J; Zmolek, Andrew C; Irvine, Darrell J

    2016-03-01

    The need to optimize vaccine potency while minimizing toxicity in healthy recipients has motivated studies of the formulation of vaccines to control how, when, and where antigens and adjuvants encounter immune cells and other cells/tissues following administration. An effective subunit vaccine must traffic to lymph nodes (LNs), activate both the innate and adaptive arms of the immune system, and persist for a sufficient time to promote a mature immune response. Here, we review approaches to tailor these three aspects of vaccine function through optimized formulations. Traditional vaccine adjuvants activate innate immune cells, promote cell-mediated transport of antigen to lymphoid tissues, and promote antigen retention in LNs. Recent studies using nanoparticles and other lymphatic-targeting strategies suggest that direct targeting of antigens and adjuvant compounds to LNs can also enhance vaccine potency without sacrificing safety. The use of formulations to regulate biodistribution and promote antigen and inflammatory cue co-uptake in immune cells may be important for next-generation molecular adjuvants. Finally, strategies to program vaccine kinetics through novel formulation and delivery strategies provide another means to enhance immune responses independent of the choice of adjuvant. These technologies offer the prospect of enhanced efficacy while maintaining high safety profiles necessary for successful vaccines. PMID:26928033

  18. Antigen-specific T cell activation independently of the MHC: chimeric antigen receptor (CAR-redirected T cells.

    Directory of Open Access Journals (Sweden)

    Hinrich eAbken

    2013-11-01

    Full Text Available Adoptive T cell therapy has recently shown powerful in initiating a lasting anti-tumor response with spectacular therapeutic success in some cases. Specific T cell therapy, however, is limited since a number of cancer cells are not recognized by T cells due to various mechanisms including the limited availability of tumor-specific T cells and deficiencies in antigen processing or major histocompatibility complex (MHC expression of cancer cells. To make adoptive cell therapy applicable for the broad variety of cancer entities, patient's T cells are engineered ex vivo with pre-defined specificity by a recombinant chimeric antigen receptor (CAR which consists in the extracellular part of an antibody-derived domain for binding with a tumor-associated antigen and in the intracellular part of a TCR-derived signaling moiety for T cell activation. The specificity of CAR mediated T cell recognition is defined by the antibody domain, is independent of MHC presentation and can be extended to any target for which an antibody is available. We discuss the advantages and limitations of MHC-independent T cell targeting by an engineered CAR and review most significant progress recently made in early stage clinical trials to treat cancer.

  19. Partial chemical characterization of antigenic preparations of chromoblastomycosis agents Caracterização química parcial de preparações antigênicas de agentes da cromoblastomicose

    OpenAIRE

    Tania Fraga BARROS; de Resende, Maria Aparecida

    1999-01-01

    Antigenic preparations (saline, methylic, metabolic and exoantigens) of four agents of chromoblastomycosis, Fonsecaea pedrosoi, Phialophora verrucosa, Cladophialophora (Cladosporium) carrionii and Rhinocladiella aquaspersa were obtained. Partial chemical characterization of these antigenic preparations was obtained by determination of the levels of total lipids, protein, and carbohydrates, and identification of the main sterols and carbohydrates. Methylic antigens presented the highest lipid ...

  20. Antigen-specific murine T cell clones produce soluble interleukin 2 receptor on stimulation with specific antigens

    International Nuclear Information System (INIS)

    In this study, monoclonal antibodies were used to the murine IL 2 receptor (IL 2R) termed 3C7 and 7D4, which bind to different epitopes on the murine IL 2R, to develop an ELISA to measure soluble murine IL 2R. Surprisingly, stimulated murine spleen cells not only expressed cell-associated IL 2R, but also produced a considerable level of cellfree IL 2R in the culture supernatant fluid. To assess the fine specificity of this response, myoglobin-immune murine T cell clones were stimulated with appropriate or inappropriate antigen and syngeneic or allogeneic presenting cells. Proliferation, measured by [3H] thymidine incorporation, and levels of soluble IL 2R were determined at day 4. The production of soluble IL2R displayed the same epitope fine specificity, genetic restriction, and antigen dose-response as the proliferative response. Indeed, in some cases there was sharper discrimination of epitope specificity and genetic restriction with the soluble IL 2R levels. There was also reproducible clone-to-clone variation in the amount of soluble receptor produced in response to antigen among 12 T cell clones and lines tested. In time course experiments, proliferation was greatest at day 3, whereas soluble IL 2R levels continued to rise in subsequent days. To the authors' knowledge, this is the first demonstration of release of secretion of soluble IL 2R by murine T cells, and the first demonstration of the fine specificity and genetic restriction of the induction of soluble IL 2R by specific antigen

  1. Common antigens of streptococcal and non-streptococcal oral bacteria: immunochemical studies of extracellular and cell-wall-associated antigens from Streptococcus sanguis, Streptococcus mutans, Lactobacillus salivarius, and Actinomyces viscosus.

    Science.gov (United States)

    Schöller, M; Klein, J P; Frank, R M

    1981-01-01

    Soluble extracellular antigens (ESA) were prepared from the culture supernatant of exponential growing cells of Streptococcus sanguis OMZ 9 by a combination of ammonium sulfate precipitation and chromatography on a Bio-Gel P6 column. Soluble cell wall antigens (WEA) were obtained from the bacterial pellet by extraction with 1 M phosphate buffer (pH 6). Antisera against whole cells of S. sanguis and S. mutans of different serotypes, 10% trichloroacetic extracts of bacterial cell walls, dextran, ESA, and WEA were prepared by injecting the different antigens several times in rabbits. ESA and WEA were prepared from a representative strain of Bratthall's seven serological groups, Lactobacillus salivarius, and Actinomyces viscosus. All sera showed various agglutinin titers against heat-killed cells, and titers were generally higher with homologous cells. The comparison of the different antigens using agar gel diffusion and immunoelectrophoresis showed the presence of extracellular common antigens in both ESA and WEA between the different strains. Absorption of anti-ESA sera with WEA, and anti-WEA sera with ESA, showed the existence of a specific antigen common to all bacteria in each fraction. Enzymatic treatment of the antigen before immunodiffusion demonstrated the protein nature of the two antigens present in ESA and WEA. Images PMID:6783541

  2. Blood group antigen studies using CdTe quantum dots and flow cytometry.

    Science.gov (United States)

    Cabral Filho, Paulo E; Pereira, Maria I A; Fernandes, Heloise P; de Thomaz, Andre A; Cesar, Carlos L; Santos, Beate S; Barjas-Castro, Maria L; Fontes, Adriana

    2015-01-01

    New methods of analysis involving semiconductor nanocrystals (quantum dots [QDs]) as fluorescent probes have been highlighted in life science. QDs present some advantages when compared to organic dyes, such as size-tunable emission spectra, broad absorption bands, and principally exceptional resistance to photobleaching. Methods applying QDs can be simple, not laborious, and can present high sensibility, allowing biomolecule identification and quantification with high specificity. In this context, the aim of this work was to apply dual-color CdTe QDs to quantify red blood cell (RBC) antigen expression on cell surface by flow cytometric analysis. QDs were conjugated to anti-A or anti-B monoclonal antibodies, as well as to the anti-H (Ulex europaeus I) lectin, to investigate RBCs of A1, B, A1B, O, A2, and Aweak donors. Bioconjugates were capable of distinguishing the different expressions of RBC antigens, both by labeling efficiency and by flow cytometry histogram profile. Furthermore, results showed that RBCs from Aweak donors present fewer amounts of A antigens and higher amounts of H, when compared to A1 RBCs. In the A group, the amount of A antigens decreased as A1 > A3 > AX = Ael, while H antigens were AX = Ael > A1. Bioconjugates presented stability and remained active for at least 6 months. In conclusion, this methodology with high sensibility and specificity can be applied to study a variety of RBC antigens, and, as a quantitative tool, can help in achieving a better comprehension of the antigen expression patterns on RBC membranes. PMID:26185442

  3. Antigen sampling in the fish intestine.

    Science.gov (United States)

    Løkka, Guro; Koppang, Erling Olaf

    2016-11-01

    Antigen uptake in the gastrointestinal tract may induce tolerance, lead to an immune response and also to infection. In mammals, most pathogens gain access to the host though the gastrointestinal tract, and in fish as well, this route seems to be of significant importance. The epithelial surface faces a considerable challenge, functioning both as a barrier towards the external milieu but simultaneously being the site of absorption of nutrients and fluids. The mechanisms allowing antigen uptake over the epithelial barrier play a central role for maintaining the intestinal homeostasis and regulate appropriate immune responses. Such uptake has been widely studied in mammals, but also in fish, a number of experiments have been reported, seeking to reveal cells and mechanisms involved in antigen sampling. In this paper, we review these studies in addition to addressing our current knowledge of the intestinal barrier in fish and its anatomical construction. PMID:26872546

  4. Antigenic typing Polish isolates of canine parvovirus

    International Nuclear Information System (INIS)

    Polish strains of canine parvovirus isolated between 1982 and 1993 were examined to determine the extent to which the virus has evolved antigenically and genetically over eleven years. Two CPV isolates obtained in Warsaw in 1982 and Pulawy in 1993, were examined using monoclonal antibody typing, restriction analysis and sequencing VP-2 protein gene. Five other isolates from Warsaw and Pulawy were tested with the panel of monoclonal antibodies specific to CPV-2, CPV-2a and common for canine parvovirus, feline panleukopenia virus and milk enteritis virus. Results of the studies demonstrated that all isolates tested represented CPV-2a antigenic type. Rapid antigenic strain replacement recorded by Parrish and Senda in the U.S.A and Japan was not confirmed in Poland. (author). 30 refs, 2 tabs

  5. Antigenic typing Polish isolates of canine parvovirus

    Energy Technology Data Exchange (ETDEWEB)

    Mizak, B. [National Veterinary Research Institute, Pulawy (Poland); Plucienniczak, A. [Polish Academy ofd Sciences. Microbiology and Virology Center, Lodz (Poland)

    1995-12-31

    Polish strains of canine parvovirus isolated between 1982 and 1993 were examined to determine the extent to which the virus has evolved antigenically and genetically over eleven years. Two CPV isolates obtained in Warsaw in 1982 and Pulawy in 1993, were examined using monoclonal antibody typing, restriction analysis and sequencing VP-2 protein gene. Five other isolates from Warsaw and Pulawy were tested with the panel of monoclonal antibodies specific to CPV-2, CPV-2a and common for canine parvovirus, feline panleukopenia virus and milk enteritis virus. Results of the studies demonstrated that all isolates tested represented CPV-2a antigenic type. Rapid antigenic strain replacement recorded by Parrish and Senda in the U.S.A and Japan was not confirmed in Poland. (author). 30 refs, 2 tabs.

  6. Sialic acid-modified antigens impose tolerance via inhibition of T-cell proliferation and de novo induction of regulatory T cells.

    Science.gov (United States)

    Perdicchio, Maurizio; Ilarregui, Juan M; Verstege, Marleen I; Cornelissen, Lenneke A M; Schetters, Sjoerd T T; Engels, Steef; Ambrosini, Martino; Kalay, Hakan; Veninga, Henrike; den Haan, Joke M M; van Berkel, Lisette A; Samsom, Janneke N; Crocker, Paul R; Sparwasser, Tim; Berod, Luciana; Garcia-Vallejo, Juan J; van Kooyk, Yvette; Unger, Wendy W J

    2016-03-22

    Sialic acids are negatively charged nine-carbon carboxylated monosaccharides that often cap glycans on glycosylated proteins and lipids. Because of their strategic location at the cell surface, sialic acids contribute to interactions that are critical for immune homeostasis via interactions with sialic acid-binding Ig-type lectins (siglecs). In particular, these interactions may be of importance in cases where sialic acids may be overexpressed, such as on certain pathogens and tumors. We now demonstrate that modification of antigens with sialic acids (Sia-antigens) regulates the generation of antigen-specific regulatory T (Treg) cells via dendritic cells (DCs). Additionally, DCs that take up Sia-antigen prevent formation of effector CD4(+) and CD8(+)T cells. Importantly, the regulatory properties endowed on DCs upon Sia-antigen uptake are antigen-specific: only T cells responsive to the sialylated antigen become tolerized. In vivo, injection of Sia-antigen-loaded DCs increased de novo Treg-cell numbers and dampened effector T-cell expansion and IFN-γ production. The dual tolerogenic features that Sia-antigen imposed on DCs are Siglec-E-mediated and maintained under inflammatory conditions. Moreover, loading DCs with Sia-antigens not only inhibited the function of in vitro-established Th1 and Th17 effector T cells but also significantly dampened ex vivo myelin-reactive T cells, present in the circulation of mice with experimental autoimmune encephalomyelitis. These data indicate that sialic acid-modified antigens instruct DCs in an antigen-specific tolerogenic programming, enhancing Treg cells and reducing the generation and propagation of inflammatory T cells. Our data suggest that sialylation of antigens provides an attractive way to induce antigen-specific immune tolerance. PMID:26941238

  7. 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

  8. Reliable diagnosis of murine type 1 diabetes using a panel of autoantigens and "antigen surrogates" mounted onto a liquid array.

    Science.gov (United States)

    Doran, Todd M; Morimoto, Jumpei; Simanski, Scott; McEnaney, Patrick J; Kodadek, Thomas

    2015-11-01

    Autoantibodies raised against β cell antigens are the most reliable preclinical biomarkers for predicting the imminent onset of type 1 diabetes mellitus (T1DM). The most current detection platforms are technically challenging or are run on clinically esoteric equipment. Here, we present a straightforward approach to detect autoantibody biomarkers that employs highly PEGylated microspheres onto which are mounted various capture agents that include affinity-tagged antigens or small molecule "antigen surrogates." After incubation with small quantities of serum, the bound autoantibodies can be measured using a standard flow cytometer. By multiplexing this assay, we show that a panel of antigen and antigen surrogates reliably predicts hyperglycemia in a mouse model of diabetes without false positives. PMID:26390856

  9. Discovery of T cell antigens by high-throughput screening of synthetic minigene libraries.

    Directory of Open Access Journals (Sweden)

    Brian D Hondowicz

    Full Text Available The identification of novel T cell antigens is central to basic and translational research in autoimmunity, tumor immunology, transplant immunology, and vaccine design for infectious disease. However, current methods for T cell antigen discovery are low throughput, and fail to explore a wide range of potential antigen-receptor interactions. To overcome these limitations, we developed a method in which programmable microarrays are used to cost-effectively synthesize complex libraries of thousands of minigenes that collectively encode the content of hundreds of candidate protein targets. Minigene-derived mRNA are transfected into autologous antigen presenting cells and used to challenge complex populations of purified peripheral blood CD8+ T cells in multiplex, parallel ELISPOT assays. In this proof-of-concept study, we apply synthetic minigene screening to identify two novel pancreatic islet autoantigens targeted in a patient with Type I Diabetes. To our knowledge, this is the first successful screen of a highly complex, synthetic minigene library for identification of a T cell antigen. In principle, responses against the full protein complement of any tissue or pathogen can be assayed by this approach, suggesting that further optimization of synthetic libraries holds promise for high throughput antigen discovery.

  10. The Ability of Immunoglobulin Yolk Recognized the Antigen in the Tissue of Ascaridia galli

    Directory of Open Access Journals (Sweden)

    Darmawi

    2012-12-01

    Full Text Available Antigen-antibody reaction is an important tool for the analysis of localization of target molecules, including antigenic protein within worm tissues. The purpose of the present research was to demonstrate the ability of immunoglobulin yolk (IgY anti-excretory/secretory recognized the antigen in the tissue of Ascaridia galli by mean of immunohistochemistry method. The excretory/secretory protein was procured from A. galli and concentrated by mean of vivaspin 30,000 MWCO. IgY was produced by egg yolks of immunized chickens with excretory/secretory, and purified using fast protein liquid chromatography (FPLC method. A. galli adult worms were cut in transversal and longitudinal section of the center and anterior region. Slides were incubated with both primary IgY for overnight at 4 oC and secondary antibody rabbit anti-chicken IgY HRP-conjugate for one hour at room temperature. The slides were stained with 3-amino, 9-ethylcarbazole (AEC chromogen, counterstained with Lillie Mayer Haematoxylin, and mounted in glyserin aqueous mount. Antigen-antibody reaction was investigated under a microscope. The result showed that antigen was appeared in the tissues such as cuticle, epicuticle, buccal cavity, and eggs inside the uterine of A. galli. This research concluded that IgY stimulated by the excretory/secretory was able to recognized the antigen scattered in the tissues of A. galli so the IgY could be applied for immunodiagnostic.

  11. Association of Alport's syndrome with HLA-DR2 antigen in a group of unrelated patients

    Directory of Open Access Journals (Sweden)

    E.A. Donadi

    1998-04-01

    Full Text Available A few family studies have evaluated HLA antigens in Alport's syndrome; however, there are no large population studies. In the present report, we studied 40 unrelated white patients with Alport's syndrome seen at the Unit of Renal Transplantation, Faculty of Medicine of Ribeirão Preto, São Paulo, Brazil. HLA-A, -B, -DR and -DQ antigens were typed using a complement-dependent microlymphocytotoxicity assay. A control white population (N = 403 from the same geographical area was also typed for HLA antigens. Although the frequencies of HLA-A and -B antigens of patients were not statistically different from controls, the frequency of HLA-DR2 antigen observed in patients (65% was significantly increased in relation to controls (26%; P<0.001. The relative risk and etiologic fraction for HLA-DR2 antigen were 5.2 and 0.525, respectively. Although few immunological abnormalities have been shown in Alport's syndrome, in this report we emphasize the association of HLA molecules and Alport's syndrome. Besides the well-known inherited molecular defects encoded by type IV collagen genes in Alport's syndrome, the major histocompatibility alleles may be in linkage disequilibrium with these defective collagen genes

  12. The antigenic property of the H5N1 avian influenza viruses isolated in central China

    Directory of Open Access Journals (Sweden)

    Zou Wei

    2012-08-01

    Full Text Available Abstract Background Three influenza pandemics outbroke in the last century accompanied the viral antigen shift and drift, resulting in the change of antigenic property and the low cross protective ability of the existed antibody to the newly emerged pandemic virus, and eventually the death of millions of people. The antigenic characterizations of the viruses isolated in central China in 2004 and 2006–2007 were investigated in the present study. Results Hemagglutinin inhibition assay and neutralization assay displayed differential antigenic characteristics of the viruses isolated in central China in two periods (2004 and 2006–2007. HA genes of the viruses mainly located in two branches in phylogeny analysis. 53 mutations of the deduced amino acids of the HA genes were divided into 4 patterns. Mutations in pattern 2 and 3 showed the main difference between viruses isolated in 2004 and 2006–2007. Meanwhile, most amino acids in pattern 2 and 3 located in the globular head of the HA protein, and some of the mutations evenly distributed at the epitope sites. Conclusions The study demonstrated that a major antigenic drift had occurred in the viruses isolated in central China. And monitoring the antigenic property should be the priority in preventing the potential pandemic of H5N1 avian influenza virus.

  13. 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.

  14. Coupling of HIV-1 Antigen to the Selective Autophagy Receptor SQSTM1/p62 Promotes T-Cell-Mediated Immunity

    Science.gov (United States)

    Andersen, Aram Nikolai; Landsverk, Ole Jørgen; Simonsen, Anne; Bogen, Bjarne; Corthay, Alexandre; Øynebråten, Inger

    2016-01-01

    Vaccines aiming to promote T-cell-mediated immune responses have so far showed limited efficacy, and there is a need for novel strategies. Studies indicate that autophagy plays an inherent role in antigen processing and presentation for CD4+ and CD8+ T cells. Here, we report a novel vaccine strategy based on fusion of antigen to the selective autophagy receptor sequestosome 1 (SQSTM1)/p62. We hypothesized that redirection of vaccine antigen from proteasomal degradation into the autophagy pathway would increase the generation of antigen-specific T cells. A hybrid vaccine construct was designed in which the antigen is fused to the C-terminus of p62, a signaling hub, and a receptor that naturally delivers ubiquitinated cargo for autophagic degradation. Fusion of the human immunodeficiency virus-1 antigen Gagp24 to p62 resulted in efficient antigen delivery into the autophagy pathway. Intradermal immunization of mice revealed that, in comparison to Gagp24 delivered alone, fusion to p62 enhanced the number of Gagp24-specific interferon-γ-producing T cells, including CD8+ T cells. The strategy may also have the potential to modulate the antigenic peptide repertoire. Because p62 and autophagy are highly conserved between species, we anticipate this strategy to be a candidate for the development of T-cell-based vaccines in humans.

  15. Antibodies recognizing a variety of different structural motifs on meningococcal Lip antigen fail to demonstrate bactericidal activity.

    Science.gov (United States)

    Tinsley, C R; Virji, M; Heckels, J E

    1992-11-01

    The neisserial Lip antigen is a conserved antigen associated with the pathogenic Neisseria species, and is composed of multiple repeats of a consensus pentapeptide. A series of monoclonal antibodies reacting with meningococcal Lip antigen were subjected to epitope mapping, using solid-phase synthetic peptides based on the consensus repeat sequence. The antibodies were found to recognize different continuous epitopes based on the consensus sequence. One monoclonal antibody was utilized in affinity chromatography to obtain purified Lip antigen and the antigen was used for immunization of mice. The resulting antisera did not recognize Lip antigen on Western blots but reacted specifically with Lip antigen in immune precipitation experiments, indicating that the predominant polyclonal immune response was directed against conformational epitopes. Despite the diversity of both continuous and conformational epitopes recognized by the antibodies produced, none of the antibodies demonstrated the ability to promote complement-mediated bactericidal activity. Thus despite its initial apparent promise as a potential vaccine candidate the case for the inclusion of Lip antigen in vaccine formulation cannot be supported at present. PMID:1282535

  16. Cytostructural Localization of a Tumor-Associated Antigen

    Science.gov (United States)

    Howard, Donald R.; Batsakis, John G.

    1980-10-01

    Tumor cell membrane glycoproteins may be involved in the induction of tumor immunity or in the escape of tumors from immunologic defense mechanisms. Forty-four benign and malignant breast lesions were examined for the presence of a carbohydrate precursor antigen (T antigen) of the human blood group system MN. T antigen was demonstrated by means of an immunohistochemical technique to detect tissue binding of peanut agglutinin, a plant lectin, with affinity for T antigen. Malignant breast lesions showed a pattern of T antigen expression different from that of benign breast tissues. A possible role for T antigen in the modulation of the immune response to breast carcinoma is suggested.

  17. Prevalence of hepatitis B surface antigen, hepatitis B e antigen and antibody, and antigen subtypes in atomic bomb survivors

    International Nuclear Information System (INIS)

    On the basis of previous studies showing an association between hepatitis B surface antigen (HBsAg) positivity and radiation exposure in atomic bomb (A-bomb) survivors, we investigated further the active state of hepatitis B virus (HBV) infection by incorporating tests of hepatitis B e antigen (HBeAg) and hepatitis B e antibody (anti-HBe) and HBsAg subtypes into our biennial health examinations. Among 6548 A-bomb survivors for whom HBsAg was assayed between July 1979 and July 1981, 129 persons were HBsAg positive. HBeAg and anti-HBe were measured in 104 of these persons and subtypes of HBsAg in 98 persons. Among those exposed to radiation (average liver dose 0.58 Sv), the odds ratio of HBsAg positivity tended to increase with radiation dose (P for trend = 0.024). The P values for association between the prevalence of HB e antigen and radiation dose were 0.094 and 0.17, respectively. The HB antigen subtype adr was predominant over other subtypes in both Hiroshima and Nagasaki, but the distribution of subtypes did not seem to differ in relation to radiation dose. These results suggested that A-bomb survivors remain in active state of HBV infection and that the mechanism(s) of seroconversion may be impaired. 29 refs., 6 tabs

  18. Nonprostatic sources of prostate-specific antigen.

    Science.gov (United States)

    Diamandis, E P; Yu, H

    1997-05-01

    The name prostate-specific antigen has been given to a protein that now is known not to be prostate-specific; however, prostatic tissue does produces extremely high levels of PSA and secrets it into the seminal plasma. Seminal plasma contains about 1 million micrograms/L of PSA and is the richest source of PSA reported. The biologic fluid with the second highest PSA concentration, however, is nipple aspirate fluid from the female breast (up to about 5000 micrograms/L), and the third is milk from lactating women (up to 300 micrograms/L). Male serum PSA is usually less than 4 micrograms/L. In nonprostatic tissues, PSA exists mainly in its free molecular form, but PSA-ACT complex is also present in most of the fluids that contain PSA, such as breast secretions and amniotic fluid. The gene expression and protein production of PSA in nonprostatic tissues are under the regulation of steroid hormones via their receptors. Androgens, glucocorticoids, and progestins up-regulate the PSA gene expression, resulting in an increase of protein production. Estrogen by itself seems to have no effect on PSA regulation, but it can impair PSA production induced by androgen. It remains unknown whether PSA is enzymatically active and what is the physiologic role of PSA in nonprostatic tissues. It is speculated that PSA may be involved in the regulation of growth factors. Measuring PSA in breast cancer cytosol, breast-nipple aspirate fluid, and female serum may have potential clinical utilities, including breast cancer prognosis, breast cancer risk assessment, and evaluation of androgen excess. Further studies are needed to identify the exact function and regulation of PSA in nonprostatic tissues and to explore the clinical application of this protein. PMID:9126224

  19. Delivery of Exogenous Antigens to Induce Cytotoxic CD8+ T Lymphocyte Responses

    Directory of Open Access Journals (Sweden)

    Julia Kim

    2010-01-01

    Full Text Available Vaccines intended to induce a cytotoxic CD8+ T-cell response are highly sought after. However, some of these vaccines can be problematic if they replicate in the host. An alternative strategy is to exploit cross-presentation of exogenous antigens to express peptides on major histocompatibility complex (MHC class I molecules. During cross-presentation, the delivered exogenous antigen can be taken up and processed through diverse mechanisms. Here, we will discuss the recent advances regarding the complex nature of the cross-priming process and the models that reflect its relevance in vivo. Moreover, we summarize current data that explore potential adjuvants and vaccine vectors that deliver antigens to activate CD8+ T cells relying on cross-presentation.

  20. Post-Transcriptional and Epigenetic Regulation of Antigen Processing Machinery (APM) Components and HLA-I in Cervical Cancers from Uighur Women

    OpenAIRE

    HASIM, AYSHAMGUL; Abudula, Mangnishahan; Aimiduo, Reshalaiti; Ma, Jun-Qi; JIAO, Zhen; Akula, Gulzareye; Wang, Ting; ABUDULA, ABULIZI

    2012-01-01

    Normal function of human leukocyte antigen class I (HLA-I) and antigen processing machinery (APM) proteins is required for T cell-mediated anti-tumor or antiviral immunity, whereas the tumor survival indicates a failure of the host in immune surveillance associated with the dysfunction in antigen presentation, mainly due to the deregulation in HLA-I and APM expression or function. The posttranscriptional regulation of HLA-I and APM expression may associate with epigenetic modifications in can...

  1. Evaluation of Intracellular Signaling Downstream Chimeric Antigen Receptors

    OpenAIRE

    Karlsson, Hannah; Svensson, Emma; Gigg, Camilla; Jarvius, Malin; Olsson-Strömberg, Ulla; Savoldo, Barbara; Dotti, Gianpietro; Loskog, Angelica

    2015-01-01

    CD19-targeting CAR T cells have shown potency in clinical trials targeting B cell leukemia. Although mainly second generation (2G) CARs carrying CD28 or 4-1BB have been investigated in patients, preclinical studies suggest that third generation (3G) CARs with both CD28 and 4-1BB have enhanced capacity. However, little is known about the intracellular signaling pathways downstream of CARs. In the present work, we have analyzed the signaling capacity post antigen stimulation in both 2G and 3G C...

  2. Human leucocyte antigens in patients with alcoholic liver cirrhosis

    DEFF Research Database (Denmark)

    Gluud, C; Aldershvile, J; Dietrichson, O;

    1980-01-01

    No significant differences in the frequencies of HLA-B8, -B40, and other HLA-A, -B, and -C phenotypes were found among patients with histologically verified alcoholic cirrhosis compared with normal controls when the p values were multiplied by the number of comparisons. This was found both in the...... present study of 45 patients and in the combined data of this and three other similar studies. However, these findings do not rule out that alcoholic cirrhosis might be associated with HLA factors (for example. HLA-D/DR antigens) controlling immune responses....

  3. Antigenic characterisation of lyssaviruses in South Africa

    Directory of Open Access Journals (Sweden)

    Ernest Ngoepe

    2014-02-01

    Full Text Available There are at least six Lyssavirus species that have been isolated in Africa, which include classical rabies virus, Lagos bat virus, Mokola virus, Duvenhage virus, Shimoni bat virus and Ikoma lyssavirus. In this retrospective study, an analysis of the antigenic reactivity patterns of lyssaviruses in South Africa against a panel of 15 anti-nucleoprotein monoclonal antibodies was undertaken. A total of 624 brain specimens, collected between 2005 and 2009, confirmed as containing lyssavirus antigen by direct fluorescent antibody test, were subjected to antigenic differentiation. The lyssaviruses were differentiated into two species, namely rabies virus (99.5% and Mokola virus (0.5%. Furthermore, rabies virus was further delineated into two common rabies biotypes in South Africa: canid and mongoose. Initially, it was found that the canid rabies biotype had two reactivity patterns; differential staining was observed with just one monoclonal antibody. This difference was likely to have been an artefact related to sample quality, as passage in cell culture restored staining. Mongoose rabies viruses were more heterogeneous, with seven antigenic reactivity patterns detected. Although Mokola viruses were identified in this study, prevalence and reservoir host species are yet to be established. These data demonstrate the usefulness of monoclonal antibody typing panels in lyssavirus surveillance with reference to emergence of new species or spread of rabies biotypes to new geographic zones.

  4. Antigen dynamics of follicular dendritic cells

    NARCIS (Netherlands)

    Heesters, B.A.

    2015-01-01

    Stromal-derived follicular dendritic cells (FDCs) are a major depot for antigen that are essential for formation of germinal centers, the site where memory and effector B cells differentiate and high-affinity antibody production takes place. Historically, FDCs have been characterized as ‘accessory’

  5. Antigen expression on recurrent meningioma cells

    International Nuclear Information System (INIS)

    Meningiomas are intracranial brain tumours that frequently recur. Recurrence rates up to 20% in 20 years for benign meningiomas, up to 80% for atypical meningiomas and up to 100% for malignant meningiomas, have been reported. The most important prognostic factors for meningioma recurrence are meningioma grade, meningioma invasiveness and radicality of neurosurgical resection. The aim of our study was to evaluate the differences in antigenic expression on the surface of meningioma cells between recurrent and non-recurrent meningiomas. 19 recurrent meningiomas and 35 non-recurrent meningiomas were compared regarding the expression of MIB-1 antigen, progesterone receptors, cathepsin B and cathepsin L, using immunohistochemistry. MIB-1 antigen expression was higher in the recurrent meningioma group (p=0.001). No difference in progesterone receptor status between recurrent and non-recurrent meningiomas was confirmed. Immunohistochemical intensity scores for cathepsin B (p= 0.007) and cathepsin L (p<0.001) were both higher in the recurrent than in the non-recurrent meningioma group. MIB-1 antigen expression is higher in recurrent compared to non-recurrent meningiomas. There is no difference in expression of progesterone receptors between recurrent and non-recurrent meningiomas. Cathepsins B and L are expressed more in recurrent meningiomas

  6. Lea blood group antigen on human platelets

    International Nuclear Information System (INIS)

    One- and two-stage radioligand assays were used to determine if human platelets possess the Lea antigen. Goat IgG anti-Lea antibody was purified by multiple adsorptions with Le(a-b-) human red blood cells, followed by affinity chromatography with synthetic Lea substance and labeling with 125I. Human IgG anti-Lea antibody was used either in a two stage radioassay with 125I-labeled mouse monoclonal IgG anti-human IgG as the second antibody or, alternatively, purified by Staph protein A chromatography, labeled with 125I, and used in a one-stage radioassay. Platelets from donors of appropriate red blood cell phenotypes were incubated with the antisera, centrifuged through phthalate esters, and assayed in a gamma scintillation counter. Dose response and saturation curve analysis demonstrate the presence of Lewis a antigen on platelets from Lea+ donors. Furthermore, platelets from an Le(a-b-) donor incubated in Le (a+b-) plasma adsorb Lea antigen in a similar manner to red blood cells. The clinical significance of these antigens in platelet transfusion remains undefined

  7. Alpha-alumina nanoparticles induce efficient autophagy-dependent cross-presentation and potent antitumour response

    Science.gov (United States)

    Li, Haiyan; Li, Yuhuan; Jiao, Jun; Hu, Hong-Ming

    2011-10-01

    Therapeutic cancer vaccination is an attractive strategy because it induces T cells of the immune system to recognize and kill tumour cells in cancer patients. However, it remains difficult to generate large numbers of T cells that can recognize the antigens on cancer cells using conventional vaccine carrier systems. Here we show that α-Al2O3 nanoparticles can act as an antigen carrier to reduce the amount of antigen required to activate T cells in vitro and in vivo. We found that α-Al2O3 nanoparticles delivered antigens to autophagosomes in dendritic cells, which then presented the antigens to T cells through autophagy. Immunization of mice with α-Al2O3 nanoparticles that are conjugated to either a model tumour antigen or autophagosomes derived from tumour cells resulted in tumour regression. These results suggest that α-Al2O3 nanoparticles may be a promising adjuvant in the development of therapeutic cancer vaccines.

  8. From oncogenes to tumor antigens

    International Nuclear Information System (INIS)

    This book presents 26 manuscripts which comprise comprehensive reviews and recent experimental data from four main areas of cancer research: oncogenes, transforming proteins and growth factors; immunodeficiencies and tumors; new markers for tumor immunodiagnosis; and prospects of immunological cancer treatment. (Auth.)

  9. 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

  10. 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....

  11. Targeting of tumor-associated antigens (TAA) in experimental immunotherapy

    International Nuclear Information System (INIS)

    We have previously shown the superiority of tumor-associated antigens (TAA) to function as effective immunogens when administered with bilayer membrane vesicles called liposomes. The ability of liposomes to target TAA to host antigen-presenting cells is analyzed here. 1-Butanol extracted TAA from two syngeneic rat colon cancer tumors (WB 2054 and W 1756) was radioiodinated (131I-TAA). Free 131I and 131I-TAA (2.8 X 10(7) cpm and 75 micrograms TAA per rat) were used as tracers, with or without incorporation into liposomes (composition: sphingomyelin, cholesterol, dicetyl phosphate at 70:24:6 molar ratio). Six groups of male rats (BN X WF for WB2054 and Wistar/Furth for W1756, n = 18 each group) were injected iv with either free tracers or the tracers incorporated into liposomes. Whole blood clearance curve was biphasic (half-life alpha = 5 min; half life beta = 12 hr), suggesting a two-compartmental model of distribution. Seven animals from each group were sacrificed at set times (15 min to 48 hr), organs harvested and cpm/g of tissue estimated. Liposome 131I and liposome 131I-TAA were targeted to and retained preferentially in liver and spleen. Four animals from each group were imaged serially using a gamma camera. Matched pair analysis of regions showed persistently higher activity in liver-spleen area when liposomes were used (P less than 0.001). The uptake of radiolabeled antigens by plastic adherent mononuclear cells in liver and spleen was significantly higher when presented with liposomes (macrophage uptake index: liver = 1.65 vs 0.55; spleen = 5.85 vs 1.15; with and without liposomes, respectively)

  12. Multiple antigen glycopeptides (MAGs) with Tn tumour antigens and incorporated adjuvant: synthesis and immunobiological activities

    Czech Academy of Sciences Publication Activity Database

    Ježek, Jan; Kelkar, Shripad; Vepřek, Pavel; Hajdůch, M.; Sejbal, J.; Trnka, T.

    Napoli : Edizioni Ziino, 2002 - (Benedetti, E.; Pedone, C.), s. 524-525 ISBN 88-900948-1-8. [Peptides 2002. European Peptide Symposium /27./. Sorrento (IT), 31.08.2002-06.09.2002] R&D Projects: GA ČR GA303/01/0690 Institutional research plan: CEZ:AV0Z4055905 Keywords : Tn antigen * multiple antigen glycopeptide * synthetic vaccine Subject RIV: CE - Biochemistry

  13. [Identification of serological antigens in excretory-secretory antigens of Trichinella spiralis muscle larvae].

    Science.gov (United States)

    Huang, Xuegui; He, Lifang; Yuan, Shishan; Liu, Hui; Wang, Xin

    2016-05-01

    Objective To isolate and identify serological antigens in the excretory-secretory antigens of Trichinella spiralis muscle larvae by the combination of co-immunoprecipitation and mass spectrometric technology. Methods The serum IgG of New Zealand rabbits infected with Trichinella spiralis was isolated by ammonium sulfate precipitation. Muscle larvaes were isolated from the infected muscle, and then purified and cultured to collect excretory-secretory antigens. Serological antigens in excretory-secretory antigens were isolated by co-immunoprecipitation and SDS-PAGE, and analyzed by Western blotting. Moreover, the protein bands in New Zealand rabbit sera infected with Trichinella spiralis were identified by mass spectrometric technology. Results Indirect ELISA showed that the titer of serum antibody of New Zealand rabbits infected with Trichinella spiralis was 1:6400. The rabbit serum IgG was effectively isolated by ammonium sulfate precipitation. A total of four clear protein bands of the excretory-secretory antigens of Trichinella spiralis were obtained by electrophoresis. Among them, three clear protein bands with relative molecular mass (Mr) being 40 kDa, 50 kDa and 83 kDa were recognized by the rabbit sera infected with Trichinella spiralis but not recognized by the normal rabbit sera. The obtained four protein molecules were confirmed as serine protease, specific serine protease of muscle larvae, 43 kDa secreted glycoprotein and 53 kDa excretory-secretory antigen. Conclusion Four proteins were obtained from the excretory-secretory antigens of Trichinella spiralis muscle larvae by combination of co-immunoprecipitation and mass spectrometric technique analysis, which provided new sources and insights for the diagnosis and vaccine candidates of Trichinellosis. PMID:27126943

  14. A prospective study of serum tumour markers carcinoembryonic antigen, carbohydrate antigens 50 and 242, tissue polypeptide antigen and tissue polypeptide specific antigen in the diagnosis of pancreatic cancer with special reference to multivariate diagnostic score.

    OpenAIRE

    Pasanen, P. A.; Eskelinen, M.; Partanen, K.; Pikkarainen, P; Penttilä, I.; Alhava, E

    1994-01-01

    The aim of this study was to assess by a stepwise multivariate discriminant analysis the value of four current serum tumour markers - carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 50 and CA 242 and tissue polypeptide antigen (TPA) - and a new serum tumour marker, tissue polypeptide specific antigen (TPS), in the diagnosis of pancreatic cancer. The serum values were measured in a prospective series of patients with jaundice, with unjaundiced cholestasis and with a suspicion of chro...

  15. Single-Antigen Serological Testing for Bovine Tuberculosis▿

    OpenAIRE

    Green, Lawrence R.; Jones, Cynthia C.; Sherwood, Anne L.; Garkavi, Inna V.; Cangelosi, Gerard A.; Thacker, Tyler C.; Palmer, Mitchell V.; Waters, W. Ray; Rathe, Chris V.

    2009-01-01

    Antibody responses are useful indicators of Mycobacterium bovis infection of cattle. Tests for such responses often use multiple M. bovis antigens as detection probes. This is recommended because responses to single antigens may be too variable for consistent diagnosis. However, the use of multiple antigens increases costs and the risk of false-positive results. As an alternative, the SeraLyte-Mbv system detects responses to a single M. bovis antigen, MPB83, by using a chemiluminescent testin...

  16. Pneumocystis carinii from pigs and humans are antigenically distinct

    DEFF Research Database (Denmark)

    Christensen, C B; Settnes, Osvald Peter; Bille-Hansen, Vivi; Jorsal, Sven Erik Lind; Henriksen, S A; Lundgren, B

    1996-01-01

    The antigens of Pneumocystis carinii cysts isolated from pigs and humans were compared by the Western immunoblotting technique. Convalescent pig serum reacted with two antigens (approximately 78 kDa and 32.5 kDa) of porcine P. carinii cysts, whereas convalescent serum from humans did not react with...... porcine P. carinii cyst antigens. The results indicate that porcine and human P. carinii cysts are antigenically distinct....

  17. Characterization of antigens of the dog major histocompatibility complex

    OpenAIRE

    Feltz, Machteld

    1983-01-01

    textabstractIn this thesis, an immunochemical analysis of dog Major Histocompatibility Complex (MHC) antigens, also called DLA antigens, is described. MHC antigens play a prominent role in the immune system, particularly in the recognition of foreign material. They can be divided into four classes. As only DLA class I antigens have been defined by well characterized reagents (antisera), they were chosen as the object of the investigation

  18. Detection of antigens in urine during acute toxoplasmosis.

    OpenAIRE

    Huskinson, J; Stepick-Biek, P; Remington, J S

    1989-01-01

    Toxoplasma antigens were detected in sera and urine of mice acutely infected with Toxoplasma gondii. The concentrations of antigens in the urine samples measured by enzyme-linked immunosorbent assay were similar to those detected in the sera of the corresponding mice. The major antigens were not dialyzable and were largely destroyed by treatment with trichloroacetic acid and heat (100 degrees C for 1 h). Toxoplasma antigens were demonstrable on Western blots (immunoblots) of the urine samples.

  19. Localisation of Ca and HMFG2 antigens in breast tissue by immunoperoxidase, immunofluorescence, and immunoelectron microscopy.

    OpenAIRE

    Beckford, U; Barbatis, C; Beesley, J E; Linsell, J C; Chantler, S. M.

    1985-01-01

    The reactivities of Ca1 and HMFG2 monoclonal antibodies were compared on paraffin wax embedded breast tissues using indirect immunoperoxidase. The expression of Ca antigen, like HMFG2, is not exclusive to malignancy: Ca was present in 41/53 (77%) and HMFG2 in 42/53 (79.2%) non-malignant conditions and both were present in 33/35 (94%) carcinomas. Similar results were obtained when cryostat sections were used. Both antigens showed striking similarities in their topographical distributions, alth...

  20. Editing of CD1d-Bound Lipid Antigens by Endosomal Lipid Transfer Proteins

    OpenAIRE

    Zhou, Dapeng; Cantu, Carlos; Sagiv, Yuval; Schrantz, Nicolas; Kulkarni, Ashok B.; Qi, Xiaoyang; Mahuran, Don J.; Carlos R Morales; Grabowski, Gregory A.; Benlagha, Kamel; Savage, Paul; Bendelac, Albert; Teyton, Luc

    2003-01-01

    It is now established that CD1 molecules present lipid antigens to T cells, although it is not clear how the exchange of lipids between membrane compartments and the CD1 binding groove is assisted. We report that mice deficient in prosaposin, the precursor to a family of endosomal lipid transfer proteins (LTP), exhibit specific defects in CD1d-mediated antigen presentation and lack Vα14 NKT cells. In vitro, saposins extracted monomeric lipids from membranes and from CD1, thereby promoting the...

  1. 21 CFR 866.3402 - Plasmodium species antigen detection assays.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Plasmodium species antigen detection assays. 866... Plasmodium species antigen detection assays. (a) Identification. A Plasmodium species antigen detection assay... malaria caused by the four malaria species capable of infecting humans: Plasmodium falciparum,...

  2. 9 CFR 113.408 - Avian mycoplasma antigen.

    Science.gov (United States)

    2010-01-01

    ... with 9 CFR 114.8. If phenol is used, a direct titration with a standardized bromide-bromate solution... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Avian mycoplasma antigen. 113.408... Diagnostics and Reagents § 113.408 Avian mycoplasma antigen. Mycoplasma antigens shall be prepared...

  3. Mapping epitopes and antigenicity by site-directed masking

    Science.gov (United States)

    Paus, Didrik; Winter, Greg

    2006-06-01

    Here we describe a method for mapping the binding of antibodies to the surface of a folded antigen. We first created a panel of mutant antigens (-lactamase) in which single surface-exposed residues were mutated to cysteine. We then chemically tethered the cysteine residues to a solid phase, thereby masking a surface patch centered on each cysteine residue and blocking the binding of antibodies to this region of the surface. By these means we mapped the epitopes of several mAbs directed to -lactamase. Furthermore, by depleting samples of polyclonal antisera to the masked antigens and measuring the binding of each depleted sample of antisera to unmasked antigen, we mapped the antigenicity of 23 different epitopes. After immunization of mice and rabbits with -lactamase in Freund's adjuvant, we found that the antisera reacted with both native and denatured antigen and that the antibody response was mainly directed to an exposed and flexible loop region of the native antigen. By contrast, after immunization in PBS, we found that the antisera reacted only weakly with denatured antigen and that the antibody response was more evenly distributed over the antigenic surface. We suggest that denatured antigen (created during emulsification in Freund's adjuvant) elicits antibodies that bind mainly to the flexible regions of the native protein and that this explains the correlation between antigenicity and backbone flexibility. Denaturation of antigen during vaccination or natural infections would therefore be expected to focus the antibody response to the flexible loops. backbone flexibility | Freund's adjuvant | conformational epitope | antisera

  4. 21 CFR 660.40 - Hepatitis B Surface Antigen.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Hepatitis B Surface Antigen. 660.40 Section 660.40...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.40 Hepatitis B Surface Antigen. (a) Proper name and definition. The proper name of this...

  5. Detection of Mycobacterial Antigens in Leprosy Serum Immune Complex

    OpenAIRE

    1986-01-01

    The antigens from immune complexes of sera from patients with mycobacterial diseases were released by sodium dodecyl sulfate. The antigenic activity of the released proteins was tested by agar gel diffusion and immunoelectrophoresis. This simple method provided direct evidence for the presence of mycobacterial antigens in the immune complexes of sera from patients with leprosy and tuberculosis.

  6. Use of magnetic nanobeads to study intracellular antigen processing

    International Nuclear Information System (INIS)

    Magnetic nanobeads were covalently linked to antigens and used as a tool to simultaneously follow their intracellular transport into the cells and specifically purify the intracellular compartments implicated in antigen processing. The protein content of these vesicles was analysed by 2D-electrophoresis. Furthermore, nanobeads allowed intracellular localisation of the antigen in electron and fluorescence microscopy

  7. Use of magnetic nanobeads to study intracellular antigen processing

    Energy Technology Data Exchange (ETDEWEB)

    Perrin-Cocon, Laure A.; Chesne, Serge; Pignot-Paintrand, Isabelle; Marche, Patrice N.; Villiers, Christian L. E-mail: christian.villiers@cea.fr

    2001-07-01

    Magnetic nanobeads were covalently linked to antigens and used as a tool to simultaneously follow their intracellular transport into the cells and specifically purify the intracellular compartments implicated in antigen processing. The protein content of these vesicles was analysed by 2D-electrophoresis. Furthermore, nanobeads allowed intracellular localisation of the antigen in electron and fluorescence microscopy.

  8. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis and western blotting for protein antigen analysis

    International Nuclear Information System (INIS)

    Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) has now become a standard tool in most laboratories for protein analysis and purification. Several SDS-PAGE systems have been described but the most widely used one is the discontinuous buffer system introduced for disc gel electrophoresis. Western blotting or the process of transfer of the electrophoretically separated proteins onto immobilizing matrices such as nitrocellulose membrane is an extension of SDS-PAGE system and provides, on the nitrocellulose blot, an identical copy of the electrophoretic separation pattern of the proteins present in the gels. The immobilized proteins can be further reacted with an appropriate probe such as antibody for identification of its corresponding antigen. The protein antigen/antibody complex is then detected by using radioactively labelled or enzyme-linked second antibody probe. The technique is very useful for analysis and characterization of complex protein antigens using immune sera from several sources or vice versa. The protocol given presented here illustrates such a separation by which complex protein antigens of blood stages of Plasmodium vivax obtained from blood of patients with vivax malaria are fractionated by SDS-PAGE and treated with immune sera from patients with acute vivax malaria and the antigen/antibody complex formed are detected by 125I-labelled anti-human immunoglobulins. 5 refs, 2 figs

  9. Expression of blood group antigens A and B in pancreas of vertebrates

    Directory of Open Access Journals (Sweden)

    ELENKA GEORGIEVA

    2012-01-01

    Full Text Available The biological role of blood group antigens (BGA A and B in tissues of different vertebrates is still controversial. There are few investigations on vertebrate pancreas and no obvious explanation of their tissue expression. The aim of the present study is to follow and compare the pancreatic expression of BGA A and B in representatives of five vertebrate classes. The biotin-streptavidin-proxidase labeling system was used for immunohistochemical detection of BGA by monoclonal antibodies to human A and B antigens. The present study reveals specific immunoreactivity in acinar and epithelial cells of pancreatic efferent ducts in species free-living vertebrates. The immunoperoxidase staining shows antigenic heterogeneity in the cellular localization. The number of positive cells and the intensity of expression vary in different species. Endothelial cells are positive only in the pancreas of Emys orbicularis. The lack of BGA A and B in some species suggests that the expression of these antigens is dependent not only on the evolutionary level of the species, but mainly on some genetic control mechanisms. The production of BGA A and B and the variability in their cellular localization probably reflect the stage of cell differentiation and the mechanisms of pancreatic secretor function. The presence of histo BGA in endodermal acinar pancreatic cells confirms the assumption for the high antigenic stability and conservatism of these molecules in vertebrate histogenesis and evolution.

  10. Analysis of GAGE, NY-ESO-1 and SP17 cancer/testis antigen expression in early stage non-small cell lung carcinoma

    DEFF Research Database (Denmark)

    Gjerstorff, Morten F; Pøhl, Mette; Olsen, Karen E; Ditzel, Henrik J

    2013-01-01

    The unique expression pattern and immunogenic properties of cancer/testis antigens make them ideal targets for immunotherapy of cancer. The MAGE-A3 cancer/testis antigen is frequently expressed in non-small cell lung cancer (NSCLC) and vaccination with MAGE-A3 in patients with MAGE-A3-positive...... NSCLC has shown promising results. However, little is known about the expression of other cancer/testis antigens in NSCLC. In the present study the expression of cancer/testis antigens GAGE, NY-ESO-1 and SP17 was investigated in patients with completely resected, early stage, primary NSCLC....

  11. Radioimmunoassay in the detection of the hepatitis Be antigen/antibody system in asymptomatic carriers of hepatitis B surface antigen

    International Nuclear Information System (INIS)

    A radioimmunoassay for hepatitis e antigen (HBeAg) and antibody to e (anti-HBe) was developed and sera of 71 asymptomatic chronic carriers of hepatitis B surface antigen (HBsAg), in 44 of whom liver biopsy was obtained, were tested. In addition, testing for Dane particle associated DNA polymerase activity was performed in all sera. HBeAg was detected in 14 subjects (19.7%) and anti-HBe in 46 (64.8%). The highest proportion of HBeAg positivity (40%) was found among carriers with histological evidence of chronic hepatitis, whereas anti-HBe was present in 80% of carriers with normal liver histology, in 58% of carriers with non-specific reactive hepatitis and in 60% of carriers with chronic liver lesions. DNA polymerase activity was present in 92.8% of sera positive for HBeAg, in 13% of sera positive for anti HBe, and in 9% of sera negative for both markers. Our results demonstrate that not all HBsAg carriers reactive to HBeAg show evidence of chronic hepatitis nor, conversely, that anti-HBe is invariably associated with the healthy carrier state of HBsAg. Finally, circulating Dane particles, as revealed by the presence of serum specific DNA polymerase activity, may also be present in anti-HBe positive sera other than those of some HBsAg carriers lacking both HBeAg and anti-HBe. (orig.)

  12. Role of the H-2 complex in the induction of T cell tolerance to self minor histocompatibility antigens

    OpenAIRE

    1983-01-01

    The present study has utilized cytotoxic T lymphocyte (CTL) responses specific for minor histocompatibility (minor H) antigens as an experimental approach to determining whether recognition of self MHC determinants is involved in the induction of T cell tolerance to self antigens. It was observed that C3H.SW splenic T cells from C3H.SW leads to B10 X B10.BR radiation bone marrow chimeras contained CTL precursors (pCTL) reactive against self C3H minor H antigens + H-2k but were tolerant to sel...

  13. Application of radionuclide techniques in the characterization of antigens for vaccine development against the human malaria parasite Plasmodium falciparum

    International Nuclear Information System (INIS)

    The development of molecular vaccines against the human malaria parasite Plasmodium falciparum requires the characterization of putative protective antigens. The characterization and structural analyses of the small amounts of antigens present in the parasite is made possible by the use of radiolabelled amino acids, monosaccharides and lipids. Parasite proliferation assays, used to identify antibodies that inhibit parasite growth in vitro, utilize radiolabelled hypoxanthine. The determination of T cell epitopes is dependent on measuring lymphocyte proliferation with radiolabelled thymidine. Radiolabelled antibodies are routinely used in Western blots and epitope analysis. The use of these techniques is illustrated in the characterization of two new merozoite surface antigens. (author). 40 refs, 11 figs

  14. Killing of Brucella antigen-sensitized macrophages by T lymphocytes in bovine brucellosis.

    Science.gov (United States)

    Wyckoff, John H; Potts, Richard D

    2007-12-15

    The present study was an investigation into the role of T lymphocytes in the killing of antigen-sensitized macrophages (M Phi) in bovine brucellosis. Following confirmation of bovine T lymphocyte cell lines derived from Brucella abortus Strain 19 vaccinated steers as antigen-specific in proliferation studies using various antigens, we adapted an apoptosis assay for evaluation of cytotoxicity by these bovine T cells against autologous monocyte-derived macrophages (MDM Phi) as target cells. Various B. abortus antigen preparations were tested including whole gamma-irradiated B. abortus bacteria (gamma BA), a soluble cytosolic protein fraction and a membrane-associated protein fraction. Both polyclonal and cloned T lymphocyte cell lines exhibited cytotoxicity against MDM Phi targets in an antigen-specific fashion. Polyclonal and cloned T lymphocyte cell lines demonstrated cytotoxic responses to varying degrees against B. abortus antigens regardless of whether the antigen used was whole nonviable bacteria, a soluble protein extract or a membrane-associated fraction of extracted bacteria. To further develop correlation of these responses to an in vivo host defense mechanism, cytotoxicity was evaluated using target cells that had been infected with live B. abortus S19 or B. abortus Strain 2308. Cytotoxic responses were also demonstrated consistently against infected targets with either strain of B. abortus although in most cases, cytotoxicity was higher against target cells sensitized with gamma BA compared to those infected with live bacteria. Cloned T lymphocyte cell lines were all CD4+, CD8(-) cells indicating that the observed cytotoxic responses were most likely due to an inflammatory Th1 response and may represent an important host defense mechanism induced by vaccination with live attenuated strains of B. abortus in cattle. PMID:17904229

  15. Overlapping antigenic repertoires of variant antigens expressed on the surface of erythrocytes infected by Plasmodium falciparum

    DEFF Research Database (Denmark)

    Giha, H A; Staalsoe, T; Dodoo, D; Elhassan, I M; Roper, C; Satti, G M; Arnot, D E; Hviid, L; Theander, T G

    antibodies to some combinations of variant antigens but not to others. These results indicate that (1) a single infection will induce the production of antibodies recognizing several variants of surface-expressed antigens, (2) the repertoire of variable antigens expressed by different parasites is...

  16. super oxide dismutase, an immuno dominant antigen in mycobacteria

    International Nuclear Information System (INIS)

    Tuberculosis is an ancient human scourge that continues to be an important public health problem worldwide. To control increasing incidence of tuberculosis and development of multidrug resistant strains, there is an immense need for development new diagnostic tests and vaccines etc. by understanding pathological mechanisms. Superoxide dismutase (SOD) is a 23kDa secreted antigen of M. tuberculosis which may play an important role in intracellular survival of pathogen. Therefore, SOD was targeted to study its importance in mycobacterial infection. To achieve this goal, mice were infected with live and killed BCG. These mice were then tested for humoral and cellular response to mycobacterial SOD. Antibody level was determined by ELISA and T-cell response as noted by 3H-thymidine incorporation method. Mycobacterial SOD was found to be highly immunogenic in mice. A high antibody response was noted in mice injected with live BCG. Similarly, a good T-cell proliferation response was noted in mice that were primed with live BCG. T-cells isolated from mice were also challenged with SOD or BCG infected J774 murine macrophages. J774 cells were found to process and present mycobacterial SOD that are only recognised by T-cells of mice previously infected with the live BCG. Interferon-gamma (IFN-gamma) activated J774 cells were found to be better antigen presenting cells than IFN-gamma + LPS or LPS-activated cells. (author)

  17. MYCN: From Oncoprotein To Tumor-Associated Antigen

    Directory of Open Access Journals (Sweden)

    Vito ePistoia

    2012-11-01

    Full Text Available MYCN is a well known oncogene overexpressed in different human malignancies including neuroblastoma, rhabdomyosarcoma, medulloblastoma, astrocytoma, Wilms’ tumor and small cell lung cancer. In the case of neuroblastoma (NB, MYCN amplification is an established biomarker of poor prognosis. MYCN belongs to a family of transcription factors (the most important of which is CMYC that show a high degree of homology. Downregulation of MYC protein expression leads to tumor regression in animal models, indicating that MYC proteins represent interesting therapeutic targets.Pre-requisites for a candidate tumor-associated antigen (TAA to be targeted by immunotherapeutic approaches are the following, i expression should be tumor-restricted, ii the putative TAA should be up-regulated in cancer cells and iii protein should be processed into immunogenic peptides capable of associating to MHC molecules with high affinity. Indeed, the MYCN protein is not expressed in human adult tissues and upregulated variably in NB cells, and MYCN peptides capable of associating to HLA-A1 or –A2 molecules with high affinity have been identified. Thus the MYCN protein qualifies as putative TAA in NB.Additional issues that determine the feasibility of targeting a putative TAA with cytotoxic T lymphocytes (CTL and will be here discussed are the following, i the inadequacy of tumor cells per se to act as antigen-presenting cells witnessed, in the case of NB cells, by the low to absent expression of HLA- class I molecules, the lack of costimulatory molecules and multiple defects in the HLA class I related antigen processing machinery, and ii the immune evasion mechanisms operated by cancer cells to fool the host immune system, such as up-regulation of soluble immunosuppressive molecules (e.g. soluble MICA and HLA-G in the case of NB or generation of immunosuppressive cells in the tumor microenvironment. A final issue that deserves consideration is the strategy used to generate

  18. In situ Delivery of Tumor Antigen- and Adjuvant-Loaded Liposomes Boosts Antigen-Specific T-Cell Responses by Human Dermal Dendritic Cells.

    Science.gov (United States)

    Boks, Martine A; Bruijns, Sven C M; Ambrosini, Martino; Kalay, Hakan; van Bloois, Louis; Storm, Gert; de Gruijl, Tanja; van Kooyk, Yvette

    2015-11-01

    Dendritic cells (DCs) have an important role in tumor control via the induction of tumor-specific T-cell responses and are therefore an ideal target for immunotherapy. The human skin is an attractive site for tumor vaccination as it contains various DC subsets. The simultaneous delivery of tumor antigen with an adjuvant is beneficial for cross-presentation and the induction of tumor-specific T-cell responses. We therefore developed liposomes that contain the melanoma-associated antigen glycoprotein 100280-288 peptide and Toll-like receptor 4 (TLR4) ligand monophosphoryl lipid A (MPLA) as adjuvant. These liposomes are efficiently taken up by monocyte-derived DCs, and antigen presentation to CD8(+) T cells was significantly higher with MPLA-modified liposomes as compared with non-modified liposomes or the co-administration of soluble MPLA. We used a human skin explant model to evaluate the efficiency of intradermal delivery of liposomes. Liposomes were efficiently taken up by CD1a(+) and especially CD14(+) dermal DCs. Induction of CD8(+) T-cell responses by emigrated dermal DCs was significantly higher when MPLA was incorporated into the liposomes as compared with non-modified liposomes or co-administration of soluble MPLA. Thus, the modification of antigen-carrying liposomes with TLR ligand MPLA significantly enhances tumor-specific T-cell responses by dermal DCs and is an attractive vaccination strategy in human skin. PMID:26083554

  19. ABO blood group antigens in oral mucosa. What is new?

    DEFF Research Database (Denmark)

    Dabelsteen, Erik

    2002-01-01

    Histo-blood group ABH (O) antigens are major alloantigens in humans. These antigens are widely distributed in human tissues and undergo changes in expression during cellular differentiation and malignant development. The ABH antigens have been characterized as terminal disaccharide determinants...... healing show similarly decreased expression of A/B antigens on migrating epithelial cells. Some studies suggest that the relationship between expression of blood group antigens and cell motility can be explained by different degrees of glycosylation of integrins. Changes in ABO expression in tumours have...

  20. A competitive-inhibiton radioimmunoassay for influenza virus envelope antigens

    International Nuclear Information System (INIS)

    A double-antibody competitive-inhibition radioimmunoassay for influenza virus envelope antigens is described. A viral antigen preparation from influenza A virus recombinant MRC11 [antigenically identical to A/Port Chalmers/1/73 (H3N2)] consisting of haemagglutinin and neuraminidase was labelled with radioiodine. Rabbit antisera were allowed to react with the labelled antigen and the resultant antigen-antibody complexes were precipitated with the appropriate antiglobulin. The competitive-inhibition radioimmunoassay very sensitively elucidated differences even among closely related influenza virus strains. Attempts have been made to eliminate neuraminidase from radioimmunoprecipitation to obtain a competitive-inhibition radioimmunoassay system for haemagglutinin alone. (author)