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Sample records for antigen presenting cells

  1. [Mucose associated lymphoid tissue. Antigen presenting cells].

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    Luzardo-Baptista, Mario J; Luzardo, José Rafael

    2013-12-01

    We studied samples of normal and abnormal human mucosae, including oral tissue and uterine cervix, using electron microscopy. Special attention was given to the functions and mechanisms of defense carried out by the epithelial (EC) and dendritic cells (DC). Activated epithelial cells posses the capacity to uptake and process antigens, in order to present them, subsequently, to the dendritic cells. The structures and elements of the cells intervening on this function are: micropinocytic vesicles, multivesicular bodies, lysosomes, phagosomes, clathrin-covered vesicles, dense granules covered by a unit membrane, granules with onion likes leaves, microbodies, and dense granules with acid phosphatase activity. When they first arrive within the epithelial layers, the DC are clear with long cytoplasmic projections, which later become short, and the density of their cytoplasm increases. They possess mycropinocytic vesicles, some clathrine-covered vesicles, lysososmes and Birbeck granules. At this moment, they are known as Langerhans cells. EC and DC present many surface folds rich in micropynocytic vesicles. Between EC and DC there are many contacts (close junctions or tight junctions), through which antigens, phagocitized and processed by the EC, are given to the DC. These cells join them to major histocompatibility complex molecules or to other molecules with similar functions (CD1). Then the Langerhans cells travel to the lymphatic node to activate T cells and continue the immunologic task. So, in this way, both the EC and the DC are a link between the natural and the acquired immunological mechanisms. PMID:24502183

  2. The Antigen Presenting Cells Instruct Plasma Cell Differentiation

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    Wei eXu

    2014-01-01

    Full Text Available The professional antigen presenting cells (APCs, including many subsets of dendritic cells and macrophages, not only mediate prompt but nonspecific response against microbes, but also bridge the antigen-specific adaptive immune response through antigen presentation. In the latter, typically activated B cells acquire cognate signals from T helper cells in the germinal center of lymphoid follicles to differentiate into plasma cells, which generate protective antibodies. Recent advances have revealed that many APC subsets provide not only signal 1 (the antigen, but also signal 2 to directly instruct the differentiation process of plasma cells in a T cell-independent manner. Herein, the different signals provided by these APC subsets to direct B cell proliferation, survival, class switching and terminal differentiation are discussed. We furthermore propose that the next generation of vaccines for boosting antibody response could be designed by targeting APCs.

  3. Antigen Export Reduces Antigen Presentation and Limits T Cell Control of M. tuberculosis.

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    Srivastava, Smita; Grace, Patricia S; Ernst, Joel D

    2016-01-13

    Persistence of Mycobacterium tuberculosis results from bacterial strategies that manipulate host adaptive immune responses. Infected dendritic cells (DCs) transport M. tuberculosis to local lymph nodes but activate CD4 T cells poorly, suggesting bacterial manipulation of antigen presentation. However, M. tuberculosis antigens are also exported from infected DCs and taken up and presented by uninfected DCs, possibly overcoming this blockade of antigen presentation by infected cells. Here we show that the first stage of this antigen transfer, antigen export, benefits M. tuberculosis by diverting bacterial proteins from the antigen presentation pathway. Kinesin-2 is required for antigen export and depletion of this microtubule-based motor increases activation of antigen-specific CD4 T cells by infected cells and improves control of intracellular infection. Thus, although antigen transfer enables presentation by bystander cells, it does not compensate for reduced antigen presentation by infected cells and represents a bacterial strategy for CD4 T cell evasion.

  4. Fibroblasts as Efficient Antigen-Presenting Cells in Lymphoid Organs

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    Kundig, Thomas M.; Bachmann, Martin F.; Dipaolo, Claudio; Simard, John J. L.; Battegay, Manuel; Lother, Heinz; Gessner, Andre; Kuhlcke, Klaus; Ohashi, Pamela S.; Hengartner, Hans; Zinkernagel, Rolf M.

    1995-06-01

    Only so-called "professional" antigen-presenting cells (APCs) of hematopoietic origin are believed capable of inducing T lymphocyte responses. However, fibroblasts transfected with viral proteins directly induced antiviral cytotoxic T lymphocyte responses in vivo, without involvement of host APCs. Fibroblasts induced T cells only in the milieu of lymphoid organs. Thus, antigen localization affects self-nonself discrimination and cell-based vaccine strategies.

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

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    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

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

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    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

  7. 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.

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

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    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.

  9. 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

  10. 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...

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

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    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...

  12. An Overview of B-1 Cells as Antigen-Presenting Cells

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    Popi, Ana F.; Longo-Maugéri, Ieda M.; Mariano, Mario

    2016-01-01

    The role of B cells as antigen-presenting cells (APCs) has been extensively studied, mainly in relation to the activation of memory T cells. Considering the B cell subtypes, the role of B-1 cells as APCs is beginning to be explored. Initially, it was described that B-1 cells are activated preferentially by T-independent antigens. However, some reports demonstrated that these cells are also involved in a T-dependent response. The aim of this review is to summarize information about the ability of B-1 cells to play a role as APCs and to briefly discuss the role of the BCR and toll-like receptor signals in this process. Furthermore, some characteristics of B-1 cells, such as natural IgM production and phagocytic ability, could interfere in the participation of these cells in the onset of an adaptive response. PMID:27148259

  13. Regulation of protein synthesis and autophagy in activated dendritic cells: implications for antigen processing and presentation.

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    Argüello, Rafael J; Reverendo, Marisa; Gatti, Evelina; Pierre, Philippe

    2016-07-01

    Antigenic peptides presented in the context of major histocompatibility complex (MHC) molecules originate from the degradation of both self and non-self proteins. T cells can therefore recognize at the surface of surveyed cells, the self-peptidome produced by the cell itself (mostly inducing tolerance) or immunogenic peptides derived from exogenous origins. The initiation of adaptive immune responses by dendritic cells (DCs), through the antigenic priming of naïve T cells, is associated to microbial pattern recognition receptors engagement. Activation of DCs by microbial product or inflammatory cytokines initiates multiple processes that maximize DC capacity to present exogenous antigens and stimulate T cells by affecting major metabolic and membrane traffic pathways. These include the modulation of protein synthesis, the regulation of MHC and co-stimulatory molecules transport, as well as the regulation of autophagy, that, all together promote exogenous antigen presentation while limiting the display of self-antigens by MHC molecules.

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

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    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

  15. SPONGIOTIC DERMATITIS WITH A MIXED INFLAMMATORY INFILTRATE OF LYMPHOCYTES, ANTIGEN PRESENTING CELLS, IMMUNOGLOBULINS AND COMPLEMENT

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    Abreu Velez Ana Maria

    2011-04-01

    Full Text Available Background: The clinical and histological presentation of spongiotic dermatitis and its inflammatory infiltrates warrant further investigation. In this case documentation of a patient with cutaneous spongiotic reactivity, we aim to characterize antigen presenting cells, as well as the skin-specific cutaneous lymphocyte antigen population by multiple techniques. Case report: A 30 year old Caucasian female presented with a two week history of blistering and erosions around the vaginal, rectal and axillary areas. Material and Methods: We utilized hematoxylin and eosin histology, direct immunofluorescence, immunohistochemistry and confocal microscopy methods to evaluate the immune reaction patterns of the cutaneous inflammatory cells. Results: In the primary histologic areas of spongiotic dermatitis, a mixed population of B and T lymphocytes was seen. Ki-67 antigen proliferative index staining was accentuated in these areas, correlating with the presence of large numbers of epidermal and dermal antigen presenting cells. Among the antigen presenting cell population, we detected strong positivities with CD1a, Factor XIIIa, myeloid/hystoid antigen, S100, HAM-56, and CD68. Interestingly, immunoglobulins G, D and M and Complement factors C1q and C3 were also strongly expressed in antigen presenting cell areas, including positivity within the spongiotic epidermis and around dermal vessels. Conclusions: We document a heterogeneous population of B and T lymphocytes and the presence of multiple classes of antigen presenting cells, immunoglobulins and complement in and surrounding histologically spongiotic areas; these findings further correlated with increased levels of expression of Ki-67.

  16. 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

  17. Towards efficient cancer immunotherapy: advances in developing artificial antigen-presenting cells

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    Eggermont, L.J.; Paulis, L.E.M.; Tel, J.; Figdor, C.G.

    2014-01-01

    Active anti-cancer immune responses depend on efficient presentation of tumor antigens and co-stimulatory signals by antigen-presenting cells (APCs). Therapy with autologous natural APCs is costly and time-consuming and results in variable outcomes in clinical trials. Therefore, development of artif

  18. 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

  19. 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.

  20. 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

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    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 ...

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

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    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

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

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    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

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

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    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

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

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

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    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.

  6. Antigen-presenting cells in parotid glands contain cystatin D originating from acinar cells.

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    Nashida, Tomoko; Sato, Ritsuko; Haga-Tsujimura, Maiko; Yoshie, Sumio; Yoshimura, Ken; Imai, Akane; Shimomura, Hiromi

    2013-02-01

    Cystatin D encoded by Cst5 is a salivary classified type II cystatin. We investigated the dynamism of cystatin D by examining the distribution of cystatin D protein and mRNA in rats, to identify novel functions. The simultaneous expression of Cst5 and cystatin D was observed in parotid glands, however in situ hybridization showed that only acinar cells produced cystatin D. Synthesized cystatin D was localized in small vesicles and secreted from the apical side to the saliva, and from the basolateral side to the extracellular region, a second secretory pathway for cystatin D. We also identified antigen-presenting cells in the parotid glands that contained cystatin D without the expression of Cst5, indicating the uptake of cystatin D from the extracellular region. Cystatin D was detected in blood serum and renal tubular cells with megalin, indicating the circulation of cystatin D through the body and uptake by renal tubular cells. Thus, the novel dynamism of cystatin D was shown and a function for cystatin D in the regulation of antigen-presenting cell activity was proposed.

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

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    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.

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

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    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

  9. 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....

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

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    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.

  11. 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

  12. HIV-1 Trans Infection of CD4+ T Cells by Professional Antigen Presenting Cells

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    Charles R. Rinaldo

    2013-01-01

    Full Text Available Since the 1990s we have known of the fascinating ability of a complex set of professional antigen presenting cells (APCs; dendritic cells, monocytes/macrophages, and B lymphocytes to mediate HIV-1 trans infection of CD4+ T cells. This results in a burst of virus replication in the T cells that is much greater than that resulting from direct, cis infection of either APC or T cells, or trans infection between T cells. Such APC-to-T cell trans infection first involves a complex set of virus subtype, attachment, entry, and replication patterns that have many similarities among APC, as well as distinct differences related to virus receptors, intracellular trafficking, and productive and nonproductive replication pathways. The end result is that HIV-1 can sequester within the APC for several days and be transmitted via membrane extensions intracellularly and extracellularly to T cells across the virologic synapse. Virus replication requires activated T cells that can develop concurrently with the events of virus transmission. Further research is essential to fill the many gaps in our understanding of these trans infection processes and their role in natural HIV-1 infection.

  13. Robust and Accurate Discrimination of Self/Non-Self Antigen Presentations by Regulatory T Cell Suppression

    Science.gov (United States)

    Furusawa, Chikara; Yamaguchi, Tomoyuki

    2016-01-01

    The immune response by T cells usually discriminates self and non-self antigens, even though the negative selection of self-reactive T cells is imperfect and a certain fraction of T cells can respond to self-antigens. In this study, we construct a simple mathematical model of T cell populations to analyze how such self/non-self discrimination is possible. The results demonstrate that the control of the immune response by regulatory T cells enables a robust and accurate discrimination of self and non-self antigens, even when there is a significant overlap between the affinity distribution of T cells to self and non-self antigens. Here, the number of regulatory T cells in the system acts as a global variable controlling the T cell population dynamics. The present study provides a basis for the development of a quantitative theory for self and non-self discrimination in the immune system and a possible strategy for its experimental verification. PMID:27668873

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

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    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.

  15. 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

  16. 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.

  17. 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...

  18. Modulation of Immune Responses by Exosomes Derived from Antigen-Presenting Cells

    Science.gov (United States)

    Shenoda, Botros B.; Ajit, Seena K.

    2016-01-01

    Exosome-mediated signaling is important in mediating the inflammatory response. To exert their biological or pathophysiological functions in the recipient cells, exosomes deliver a diverse array of biomacromolecules including long and short coding and non-coding RNAs, proteins, and lipids. Exosomes secreted by antigen-presenting cells can confer therapeutic benefits by attenuating or stimulating the immune response. Exosomes play a crucial role in carrying and presenting functional major histocompatibility peptide complexes to modulate antigen-specific T cell responses. Exosomes from Dendritic Cells (DCs) can activate T and B cells and have been explored for their immunostimulatory properties in cancer therapy. The immunosuppressive properties of exosomes derived from macrophages and DCs can reduce inflammation in animal models for several inflammatory disorders. This review focuses on the protective role of exosomes in attenuating inflammation or augmenting immune response, emphasizing studies on exosomes derived from DCs and macrophages. PMID:27660518

  19. Modulation of Immune Responses by Exosomes Derived from Antigen-Presenting Cells.

    Science.gov (United States)

    Shenoda, Botros B; Ajit, Seena K

    2016-01-01

    Exosome-mediated signaling is important in mediating the inflammatory response. To exert their biological or pathophysiological functions in the recipient cells, exosomes deliver a diverse array of biomacromolecules including long and short coding and non-coding RNAs, proteins, and lipids. Exosomes secreted by antigen-presenting cells can confer therapeutic benefits by attenuating or stimulating the immune response. Exosomes play a crucial role in carrying and presenting functional major histocompatibility peptide complexes to modulate antigen-specific T cell responses. Exosomes from Dendritic Cells (DCs) can activate T and B cells and have been explored for their immunostimulatory properties in cancer therapy. The immunosuppressive properties of exosomes derived from macrophages and DCs can reduce inflammation in animal models for several inflammatory disorders. This review focuses on the protective role of exosomes in attenuating inflammation or augmenting immune response, emphasizing studies on exosomes derived from DCs and macrophages. PMID:27660518

  20. Ethanol Metabolism Alters Major Histocompatibility Complex Class I-Restricted Antigen Presentation In Liver Cells

    Science.gov (United States)

    Osna, Natalia A.; White, Ronda L.; Thiele, Geoffrey M.; Donohue, Terrence M.

    2009-01-01

    The proteasome is a major enzyme that cleaves proteins for antigen presentation. Cleaved peptides traffic to the cell surface, where they are presented in the context of MHC class I. Recognition of these complexes by cytotoxic T lymphocytes is crucial for elimination of cells bearing “non-self” proteins. Our previous studies revealed that ethanol suppresses proteasome function in ethanol-metabolizing liver cells. We hypothesized that proteasome suppression reduces the hydrolysis of antigenic peptides, thereby decreasing the presentation of the peptide-MHC class I-complexes on the cell surface. To test this, we used the mouse hepatocyte cell line (CYP2E1/ADH-transfected HepB5 cells) or primary mouse hepatocytes, both derived from livers of C57Bl/6 mice, which present the ovalbumin peptide, SIINFEKL, complexed with H2Kb. To induce H2Kb expression, HepB5 cells were treated with interferon gamma (IFNγ) and then exposed to ethanol. In these cells, ethanol metabolism decreased not only proteasome activity, but also hydrolysis of the C-extended peptide, SIINFEKL-TE and the presentation of SIINFEKL-H2Kb complexes measured after the delivery of SIINFEKL-TE to cytoplasm. The suppressive effects of ethanol were, in part, attributed to ethanol-elicited impairment of IFNγ signaling. However, in primary hepatocytes, even in the absence of IFNγ, we observed a similar decline in proteasome activity and antigen presentation after ethanol exposure. We conclude that proteasome function is directly suppressed by ethanol metabolism and indirectly, by preventing the activating effects of IFNγ. Ethanol-elicited reduction in proteasome activity contributes to the suppression of SIINFEKL-H2Kb presentation on the surface of liver cells. Immune response to viral antigens plays a crucial role in the pathogenesis of hepatitis C or B viral infections (HCV and HBV, respectively). Professional antigen-presenting cells (dendritic cells and macrophages) are responsible for priming the

  1. 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...... for cytokine expression. They were co-cultured with primed T cells to measure induction of T cell proliferation and cytokine response. RESULTS: The number of CD11c+ microglia cells increased dramatically in EAE. They expressed equivalent levels of major histocompatibility complex and co-stimulatory ligands CD...

  2. 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.

  3. A Lipid Based Antigen Delivery System Efficiently Facilitates MHC Class-I Antigen Presentation in Dendritic Cells to Stimulate CD8+ T Cells

    Science.gov (United States)

    Maji, Mithun; Mazumder, Saumyabrata; Bhattacharya, Souparno; Choudhury, Somsubhra Thakur; Sabur, Abdus; Shadab, Md.; Bhattacharya, Pradyot; Ali, Nahid

    2016-06-01

    The most effective strategy for protection against intracellular infections such as Leishmania is vaccination with live parasites. Use of recombinant proteins avoids the risks associated with live vaccines. However, due to low immunogenicity, they fail to trigger T cell responses particularly of CD8+ cells requisite for persistent immunity. Previously we showed the importance of protein entrapment in cationic liposomes and MPL as adjuvant for elicitation of CD4+ and CD8+ T cell responses for long-term protection. In this study we investigated the role of cationic liposomes on maturation and antigen presentation capacity of dendritic cells (DCs). We observed that cationic liposomes were taken up very efficiently by DCs and transported to different cellular sites. DCs activated with liposomal rgp63 led to efficient presentation of antigen to specific CD4+ and CD8+ T cells. Furthermore, lymphoid CD8+ T cells from liposomal rgp63 immunized mice demonstrated better proliferative ability when co-cultured ex vivo with stimulated DCs. Addition of MPL to vaccine enhanced the antigen presentation by DCs and induced more efficient antigen specific CD8+ T cell responses when compared to free and liposomal antigen. These liposomal formulations presented to CD8+ T cells through TAP-dependent MHC-I pathway offer new possibilities for a safe subunit vaccine.

  4. Autologous Dendritic Cells Prolong Allograft Survival Through Tmem176b-Dependent Antigen Cross-Presentation

    Science.gov (United States)

    Charnet, P.; Savina, A.; Tilly, G.; Gautreau, L.; Carretero-Iglesia, L.; Beriou, G.; Cebrian, I.; Cens, T.; Hepburn, L.; Chiffoleau, E.; Floto, R. A.; Anegon, I.; Amigorena, S.; Hill, M.; Cuturi, M. C.

    2015-01-01

    The administration of autologous (recipient-derived) tolerogenic dendritic cells (ATDCs) is under clinical evaluation. However, the molecular mechanisms by which these cells prolong graft survival in a donor-specific manner is unknown. Here, we tested mouse ATDCs for their therapeutic potential in a skin transplantation model. ATDC injection in combination with anti-CD3 treatment induced the accumulation of CD8+CD11c+ T cells and significantly prolonged allograft survival. TMEM176B is an intracellular protein expressed in ATDCs and initially identified in allograft tolerance. We show that Tmem176b−/− ATDCs completely failed to trigger both phenomena but recovered their effect when loaded with donor peptides before injection. These results strongly suggested that ATDCs require TMEM176B to cross-present antigens in a tolerogenic fashion. In agreement with this, Tmem176b−/− ATDCs specifically failed to cross-present male antigens or ovalbumin to CD8+ T cells. Finally, we observed that a Tmem176b-dependent cation current controls phagosomal pH, a critical parameter in cross-presentation. Thus, ATDCs require TMEM176B to cross-present donor antigens to induce donor-specific CD8+CD11c+ T cells with regulatory properties and prolong graft survival. PMID:24731243

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

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    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

  6. Dendritic cells take up and present antigens from viable and apoptotic polymorphonuclear leukocytes.

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    Carlos Alfaro

    Full Text Available Dendritic cells (DC are endowed with the ability to cross-present antigens from other cell types to cognate T cells. DC are poised to meet polymorphonuclear leukocytes (PMNs as a result of being co-attracted by interleukin-8 (IL-8, for instance as produced by tumor cells or infected tissue. Human monocyte-derived and mouse bone marrow-derived DC can readily internalize viable or UV-irradiated PMNs. Such internalization was abrogated at 4°C and partly inhibited by anti-CD18 mAb. In mice, DC which had internalized PMNs containing electroporated ovalbumin (OVA protein, were able to cross-present the antigen to CD8 (OT-1 and CD4 (OT-2 TCR-transgenic T cells. Moreover, in humans, tumor cell debris is internalized by PMNs and the tumor-cell material can be subsequently taken up from the immunomagnetically re-isolated PMNs by DC. Importantly, if human neutrophils had endocytosed bacteria, they were able to trigger the maturation program of the DC. Moreover, when mouse PMNs with E. coli in their interior are co-injected in the foot pad with DC, many DC loaded with fluorescent material from the PMNs reach draining lymph nodes. Using CT26 (H-2(d mouse tumor cells, it was observed that if tumor cells are intracellularly loaded with OVA protein and UV-irradiated, they become phagocytic prey of H-2(d PMNs. If such PMNs, that cannot present antigens to OT-1 T cells, are immunomagnetically re-isolated and phagocytosed by H-2(b DC, such DC productively cross-present OVA antigen determinants to OT-1 T cells. Cross-presentation to adoptively transferred OT-1 lymphocytes at draining lymph nodes also take place when OVA-loaded PMNs (H-2(d are coinjected in the footpad of mice with autologous DC (H-2(b. In summary, our results indicate that antigens phagocytosed by short-lived PMNs can be in turn internalized and productively cross-presented by DC.

  7. 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.

  8. 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

  9. Dynamic imaging of experimental Leishmania donovani-induced hepatic granulomas detects Kupffer cell-restricted antigen presentation to antigen-specific CD8 T cells.

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    Lynette Beattie

    2010-03-01

    Full Text Available Kupffer cells (KCs represent the major phagocytic population within the liver and provide an intracellular niche for the survival of a number of important human pathogens. Although KCs have been extensively studied in vitro, little is known of their in vivo response to infection and their capacity to directly interact with antigen-specific CD8(+ T cells. Here, using a combination of approaches including whole mount and thin section confocal microscopy, adoptive cell transfer and intra-vital 2-photon microscopy, we demonstrate that KCs represent the only detectable population of mononuclear phagocytes within granulomas induced by Leishmania donovani infection that are capable of presenting parasite-derived peptide to effector CD8(+ T cells. This restriction of antigen presentation to KCs within the Leishmania granuloma has important implications for the identification of new candidate vaccine antigens and for the design of novel immuno-therapeutic interventions.

  10. Peptide-beta2-microglobulin-major histocompatibility complex expressing cells are potent antigen-presenting cells that can generate specific T cells.

    Science.gov (United States)

    Obermann, Sonja; Petrykowska, Susanne; Manns, Michael P; Korangy, Firouzeh; Greten, Tim F

    2007-09-01

    Adoptive T-cell therapy represents a promising therapeutic approach for the treatment of cancer. Successful adoptive immunotherapy depends on the ex vivo priming and expansion of antigen-specific T cells. However, the in vitro generation of adequate numbers of functional antigen-specific T cell remains a major obstacle. It is important to develop efficient and reproducible methods to generate high numbers of antigen-specific T cells for adoptive T-cell transfer. We have developed a new artificial antigen-presenting cell (aAPC) by transfection of major histocompatibility (MHC) class I negative Daudi cells with a peptide-beta2-microglobulin-MHC fusion construct (single-chain aAPC) ensuring presentation of the peptide-MHC complex of interest. Using this artificial antigen-presenting cell, we could generate up to 9.2 x 10(8) antigen-specific cytotoxic CD8(+) T cells from 10 ml blood. In vitro generated T cells lysed endogenously presented antigens. Direct comparison of the single-chain aAPC with autologous monocyte-derived dendritic cells demonstrated that these cells were equally efficient in stimulation of T cells. Finally, we were able to generate antigen-specific T cell lines from perpheral blood mononuclear cells of patients receiving cytotoxic chemotherapy. The use of single-chain aAPC represent a promising option for the generation of antigen-specific CD8(+) T cells, which could be used for adoptive T-cell therapy.

  11. Peptide-β2-microglobulin-major histocompatibility complex expressing cells are potent antigen-presenting cells that can generate specific T cells

    Science.gov (United States)

    Obermann, Sonja; Petrykowska, Susanne; Manns, Michael P; Korangy, Firouzeh; Greten, Tim F

    2007-01-01

    Adoptive T-cell therapy represents a promising therapeutic approach for the treatment of cancer. Successful adoptive immunotherapy depends on the ex vivo priming and expansion of antigen-specific T cells. However, the in vitro generation of adequate numbers of functional antigen-specific T cell remains a major obstacle. It is important to develop efficient and reproducible methods to generate high numbers of antigen-specific T cells for adoptive T-cell transfer. We have developed a new artificial antigen-presenting cell (aAPC) by transfection of major histocompatibility (MHC) class I negative Daudi cells with a peptide-β2-microglobulin–MHC fusion construct (single-chain aAPC) ensuring presentation of the peptide–MHC complex of interest. Using this artificial antigen-presenting cell, we could generate up to 9·2 × 108 antigen-specific cytotoxic CD8+ T cells from 10 ml blood. In vitro generated T cells lysed endogenously presented antigens. Direct comparison of the single-chain aAPC with autologous monocyte-derived dendritic cells demonstrated that these cells were equally efficient in stimulation of T cells. Finally, we were able to generate antigen-specific T cell lines from perpheral blood mononuclear cells of patients receiving cytotoxic chemotherapy. The use of single-chain aAPC represent a promising option for the generation of antigen-specific CD8+ T cells, which could be used for adoptive T-cell therapy. PMID:17472719

  12. 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.

  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. 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

  15. 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...

  16. Antigen recognition and presentation in periapical tissues: a role for TLR expressing cells?

    Science.gov (United States)

    Desai, S V; Love, R M; Rich, A M; Seymour, G J

    2011-02-01

    Bacteria are the prime cause of periapical diseases and root canal microbiology is a well-researched area of endodontics. Antigen-presenting cells (APCs) are present in periapical lesions of endodontic origin and play a substantial role in recognizing, processing and presenting pathogenic antigens to the adaptive immune system such as an effective and long-lasting immune response is generated against the specific pathogens. Toll-like receptors (TLRs) are germ-line encoded pathogen recognition receptors (PRR) expressed by various APCs which induce their maturation, lead to gene transcription in the nucleus and the production of several pro- and anti-inflammatory cytokines. Thirteen TLRs have been discovered, 10 of which have been identified in humans so far. Preliminary studies of dental pulp tissue have demonstrated various cell types expressing different TLRs in response to commonly encountered microorganisms. However, there is little information available regarding the expression and function of the various TLRs in human periapical lesions. This review discusses the interactions of various APCs in periapical lesions and the possible roles of different TLRs and APCs in pulp/periapical pathogen recognition and presentation to the adaptive immune system in the initiation and sustaining of periapical diseases.

  17. 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.

  18. Inflammatory environment and oxidized LDL convert circulating human proangiogenic cells into functional antigen-presenting cells.

    Science.gov (United States)

    Vinci, Maria Cristina; Piacentini, Luca; Chiesa, Mattia; Saporiti, Federica; Colombo, Gualtiero I; Pesce, Maurizio

    2015-09-01

    The function of human circulating PACs has been described extensively. However, little focus has been placed on understanding how these cells differ in their functions in the presence of microenvironments mimicking vascular inflammation. We hypothesized that exposure to proinflammatory cytokines or the oxLDL, an autoantigen abundant in advanced atherosclerotic plaques, converts PACs into immune-modulating/proinflammatory cells. Hence, we examined the effect of oxLDL and inflammatory stimuli on their phenotype by use of a functional genomics model based on secretome and whole genome transcriptome profiling. PACs obtained from culturing a PBMC fraction in angiogenic medium were primed with DC differentiation cytokines and then exposed to proinflammatory cytokines or oxLDL. Under these conditions, PACs converted into APCs, expressed maturation markers CD80 and CD83, and showed an increased up-regulation of CD86. APCcy and APCox induced a robust T cell BrdU incorporation. Despite a similar ability to induce lymphocyte proliferation, APCcy and APCox differed for the secretory pathway and mRNA expression. Analysis of the differentially expressed genes identified 4 gene "clusters," showing reciprocal modulation in APCcy vs. APCox, justifying, according to functional genomics analyses, a different putative function of the cells in antigen processing. Together, these data show that treatment with inflammatory cytokines or oxLDL converts human PAC phenotypes and functions into that of APCs with similar lymphocyte-activating ability but distinct maturation degree and paracrine functions.

  19. 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

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

    Directory of Open Access Journals (Sweden)

    Xinyuan Chen

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

  1. Antigen-bound C3b and C4b enhance antigen-presenting cell function in activation of human T-cell clones.

    Science.gov (United States)

    Arvieux, J; Yssel, H; Colomb, M G

    1988-10-01

    The effect of complement fragments C3b and C4b, on the triggering of antigen-specific human T-cell clones by Epstein-Barr virus-transformed human lymphoblastoid B cells (LCL) when these fragments are covalently coupled to the antigen tetanus toxin (TT) is described. TT was chemically cross-linked to purified C3b [(TT-C3b)n], C4b [(TT-C4b)n] or bovine serum albumin [(TT-BSA)n] as a control. T-cell activation was quantified by tritiated thymidine incorporation and 51Cr release. (TT-C3b)n and (TT-C4b)n induced proliferative responses comparable to (TT-BSA)n but at 18-25 and 4-6 lower concentrations, respectively. This enhancing effect required the covalent cross-linking of the complement fragments to the antigen and involved intracellular processing of the latter by LCL. Antigen presentation was similarly enhanced when measuring the cytotoxic activity of a helper T-cell clone against LCL previously pulsed with (TT-C3b)n or (TT-C4b)n compared with (TT-BSA)n. Binding studies, carried out on LCL using TT radiolabelled with 125I before cross-linking, indicated that (TT-C3b)n and (TT-C4b)n gave three- to four-fold more binding than (TT-BSA)n. Addition of antibodies against CR1 and CR2 or proteolytic removal of these complement receptors with trypsin inhibited by about 60% the enhancing effect of TT-bound C3b and C4b in both binding and functional assays. These results indicate that binding of C3b or C4b to antigen enhances antigen-specific proliferative and cytotoxic responses of T cells by targeting opsonized antigen onto complement receptors CR1 and CR2 of LCL. The putative significance of these findings in terms of regulation of immune responses by complement is discussed. PMID:2973431

  2. Antigen-bound C3b and C4b enhance antigen-presenting cell function in activation of human T-cell clones.

    Science.gov (United States)

    Arvieux, J; Yssel, H; Colomb, M G

    1988-10-01

    The effect of complement fragments C3b and C4b, on the triggering of antigen-specific human T-cell clones by Epstein-Barr virus-transformed human lymphoblastoid B cells (LCL) when these fragments are covalently coupled to the antigen tetanus toxin (TT) is described. TT was chemically cross-linked to purified C3b [(TT-C3b)n], C4b [(TT-C4b)n] or bovine serum albumin [(TT-BSA)n] as a control. T-cell activation was quantified by tritiated thymidine incorporation and 51Cr release. (TT-C3b)n and (TT-C4b)n induced proliferative responses comparable to (TT-BSA)n but at 18-25 and 4-6 lower concentrations, respectively. This enhancing effect required the covalent cross-linking of the complement fragments to the antigen and involved intracellular processing of the latter by LCL. Antigen presentation was similarly enhanced when measuring the cytotoxic activity of a helper T-cell clone against LCL previously pulsed with (TT-C3b)n or (TT-C4b)n compared with (TT-BSA)n. Binding studies, carried out on LCL using TT radiolabelled with 125I before cross-linking, indicated that (TT-C3b)n and (TT-C4b)n gave three- to four-fold more binding than (TT-BSA)n. Addition of antibodies against CR1 and CR2 or proteolytic removal of these complement receptors with trypsin inhibited by about 60% the enhancing effect of TT-bound C3b and C4b in both binding and functional assays. These results indicate that binding of C3b or C4b to antigen enhances antigen-specific proliferative and cytotoxic responses of T cells by targeting opsonized antigen onto complement receptors CR1 and CR2 of LCL. The putative significance of these findings in terms of regulation of immune responses by complement is discussed.

  3. 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...

  4. 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.

  5. 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.

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

    Science.gov (United States)

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

    2004-04-01

    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. Unexpectedly, dendritic cells also take up actively antigens into endosomes from live infected CD4+ T lymphocytes and cross-present them as efficiently as antigens derived from apoptotic infected cells. Moreover, live infected CD4+ T cells costimulate cross-presenting dendritic cells in the process. Therefore, dendritic cells can present very small amounts of viral proteins from infected T cells either after apoptosis, which is frequent during HIV infection, or not. Thus, if HIV expression is transiently induced while costimulation is enhanced (for instance after IL-2 and IFN immune therapy), this HIV antigen presentation pathway could be exploited to eradicate latently infected reservoirs, which are poorly recognized by patients' immune systems.

  7. Selective susceptibility of human skin antigen presenting cells to productive dengue virus infection.

    Directory of Open Access Journals (Sweden)

    Daniela Cerny

    2014-12-01

    Full Text Available Dengue is a growing global concern with 390 million people infected each year. Dengue virus (DENV is transmitted by mosquitoes, thus host cells in the skin are the first point of contact with the virus. Human skin contains several populations of antigen-presenting cells which could drive the immune response to DENV in vivo: epidermal Langerhans cells (LCs, three populations of dermal dendritic cells (DCs, and macrophages. Using samples of normal human skin we detected productive infection of CD14(+ and CD1c(+ DCs, LCs and dermal macrophages, which was independent of DC-SIGN expression. LCs produced the highest viral titers and were less sensitive to IFN-β. Nanostring gene expression data showed significant up-regulation of IFN-β, STAT-1 and CCL5 upon viral exposure in susceptible DC populations. In mice infected intra-dermally with DENV we detected parallel populations of infected DCs originating from the dermis and migrating to the skin-draining lymph nodes. Therefore dermal DCs may simultaneously facilitate systemic spread of DENV and initiate the adaptive anti-viral immune response.

  8. Manufacture of clinical-grade CD19-specific T cells stably expressing chimeric antigen receptor using Sleeping Beauty system and artificial antigen presenting cells.

    Directory of Open Access Journals (Sweden)

    Harjeet Singh

    Full Text Available Adoptive transfer of T cells expressing a CD19-specific chimeric antigen receptor (CAR is being evaluated in multiple clinical trials. Our current approach to adoptive immunotherapy is based on a second generation CAR (designated CD19RCD28 that signals through a CD28 and CD3-ζ endodomain. T cells are electroporated with DNA plasmids from the Sleeping Beauty (SB transposon/transposase system to express this CAR. Stable integrants of genetically modified T cells can then be retrieved when co-cultured with designer artificial antigen presenting cells (aAPC in the presence of interleukin (IL-2 and 21. Here, we reveal how the platform technologies of SB-mediated transposition and CAR-dependent propagation on aAPC were adapted for human application. Indeed, we have initiated clinical trials in patients with high-risk B-lineage malignancies undergoing autologous and allogeneic hematopoietic stem-cell transplantation (HSCT. We describe the process to manufacture clinical grade CD19-specific T cells derived from healthy donors. Three validation runs were completed in compliance with current good manufacturing practice for Phase I/II trials demonstrating that by 28 days of co-culture on γ-irradiated aAPC ∼10(10 T cells were produced of which >95% expressed CAR. These genetically modified and propagated T cells met all quality control testing and release criteria in support of infusion.

  9. Proteasomal targeting and minigene repetition improve cell-surface presentation of a transfected, modified melanoma tumour antigen

    DEFF Research Database (Denmark)

    Rasmussen, A B; Zocca, M-B; Bonefeld, C M;

    2004-01-01

    on the density of specific major histocompatibility complex-peptide complexes on the surface of the antigen-presenting cell. In this study, we explored the cell-surface presentation of a substituted MART-1 peptide encoded by transfected minigenes. We investigated the potential of proteasomal targeting compared...

  10. "Danger" conditions increase sulfamethoxazole-protein adduct formation in human antigen-presenting cells.

    Science.gov (United States)

    Lavergne, S N; Wang, H; Callan, H E; Park, B K; Naisbitt, D J

    2009-11-01

    Antigen-presenting cells (APC) are thought to play an important role in the pathogenesis of drug-induced immune reactions. Various pathological factors can activate APC and therefore influence the immune equilibrium. It is interesting that several diseases have been associated with an increased rate of drug allergy. The aim of this project was to evaluate the impact of such "danger signals" on sulfamethoxazole (SMX) metabolism in human APC (peripheral blood mononuclear cells, Epstein-Barr virus-modified B lymphocytes, monocyte-derived dendritic cells, and two cell lines). APC were incubated with SMX (100 microM-2 mM; 5 min-24 h), in the presence of pathological factors: bacterial endotoxins (lipopolysaccharide and staphylococcal enterotoxin B), flu viral proteins, cytokines [interleukin (IL)-1beta, IL-6, IL-10; tumor necrosis factor-alpha; interferon-gamma; and transforming growth factor-beta], inflammatory molecules (prostaglandin E2, human serum complement, and activated protein C), oxidants (buthionine sulfoximine and H(2)O(2)), and hyperthermia (37.5-39.5 degrees C). Adduct formation was evaluated by enzyme-linked immunosorbent assay and confocal microscopy. SMX-protein adduct formation was time- and concentration-dependent for each cell type tested, in both physiological and danger conditions. A danger environment significantly increased the formation of SMX-protein adducts and significantly shortened the delay for their detection. An additive effect was observed with a combination of danger signals. Dimedone (chemical selectively binding cysteine sulfenic acid) and antioxidants decreased both baseline and danger-enhanced SMX-adduct formation. Various enzyme inhibitors were associated with a significant decrease in SMX-adduct levels, with a pattern varying depending on the cell type and the culture conditions. These results illustrate that danger signals enhance the formation of intracellular SMX-protein adducts in human APC. These findings might be relevant

  11. 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

  12. 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

  13. Antigen-specific B cells reactivate an effective cytotoxic T cell response against phagocytosed Salmonella through cross-presentation.

    Directory of Open Access Journals (Sweden)

    Jelle de Wit

    Full Text Available BACKGROUND: The eradication of facultative intracellular bacterial pathogens, like Salmonella typhi, requires the concerted action of both the humoral immune response and the cytotoxic CD8(+ T cell response. Dendritic cells (DCs are considered to orchestrate the cytotoxic CD8(+ T cell response via cross-presentation of bacterial antigens onto MHC class I molecules. Cross-presentation of Salmonella by DCs however, is accompanied by the induction of apoptosis in the DCs. Besides antibody production, B cells are required to clear Salmonella infection for other unknown reasons. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that Salmonella-specific B cells that phagocytose Salmonella upon BCR-ligation reactivate human memory CD8(+ T cells via cross-presentation yielding a Salmonella-specific cytotoxic T cell response. The reactivation of CD8(+ T cells is dependent on CD4(+ T cell help. Unlike the DCs, B cell-mediated cross-presentation of Salmonella does not coincide with apoptosis. CONCLUSIONS/SIGNIFICANCE: B cells form a new player in the activation of the cytotoxic effector arm of the immune response and the generation of effective adaptive immunity in Salmonella infection.

  14. CD8(+ T cells restrict Yersinia pseudotuberculosis infection: bypass of anti-phagocytosis by targeting antigen-presenting cells.

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    Molly A Bergman

    2009-09-01

    Full Text Available All Yersinia species target and bind to phagocytic cells, but uptake and destruction of bacteria are prevented by injection of anti-phagocytic Yop proteins into the host cell. Here we provide evidence that CD8(+ T cells, which canonically eliminate intracellular pathogens, are important for restricting Yersinia, even though bacteria are primarily found in an extracellular locale during the course of disease. In a model of infection with attenuated Y. pseudotuberculosis, mice deficient for CD8(+ T cells were more susceptible to infection than immunocompetent mice. Although exposure to attenuated Y. pseudotuberculosis generated T(H1-type antibody responses and conferred protection against challenge with fully virulent bacteria, depletion of CD8(+ T cells during challenge severely compromised protective immunity. Strikingly, mice lacking the T cell effector molecule perforin also succumbed to Y. pseudotuberculosis infection. Given that the function of perforin is to kill antigen-presenting cells, we reasoned that cell death marks bacteria-associated host cells for internalization by neighboring phagocytes, thus allowing ingestion and clearance of the attached bacteria. Supportive of this model, cytolytic T cell killing of Y. pseudotuberculosis-associated host cells results in engulfment by neighboring phagocytes of both bacteria and target cells, bypassing anti-phagocytosis. Our findings are consistent with a novel function for cell-mediated immune responses protecting against extracellular pathogens like Yersinia: perforin and CD8(+ T cells are critical for hosts to overcome the anti-phagocytic action of Yops.

  15. Artificial antigen-presenting cells transduced with telomerase efficiently expand epitope-specific, human leukocyte antigen-restricted cytotoxic T cells.

    Science.gov (United States)

    Dupont, Jakob; Latouche, Jean-Baptiste; Ma, Chia; Sadelain, Michel

    2005-06-15

    Human telomerase reverse transcriptase (hTERT) is overexpressed in most human tumors, making it a potential target for cancer immunotherapy. hTERT-derived CTL epitopes have been identified previously, including p865 (RLVDDFLLV) and p540 (ILAKFLHWL), which are restricted by the human leukocyte antigen (HLA) class I A*0201 allele. However, it remains a major challenge to efficiently and consistently expand hTERT-specific CTLs from donor peripheral blood T lymphocytes. To bypass the need for generating conventional antigen-presenting cells (APC) on an autologous basis, we investigated the potential ability of fibroblast-derived artificial APCs (AAPC) to activate and expand HLA-A*0201-restricted CTLs. We show here that AAPCs stably expressing HLA-A*0201, human beta(2)-microglobulin, B7.1, intercellular adhesion molecule-1, and LFA-3, together with either p540 and p865 minigenes or the full-length hTERT, effectively stimulate tumoricidal, hTERT-specific CTLs. hTERT-expressing AAPCs stimulated both p540 and p865 CTLs as shown by peptide-specific cytolysis and tetramer staining, indicating that hTERT is processed by the AAPCs and that the two peptides are presented as codominant epitopes. The level of cytotoxic activity against a panel of tumors comprising hematologic and epithelial malignancies varied, correlating overall with the level of HLA-A2 and hTERT expression by the target cell. Starting from 100 mL blood, approximately 100 million hTERT-specific CTLs could be generated over the course of five sequential stimulations, representing an expansion of approximately 1 x 10(5). Our data show that AAPCs process hTERT antigen and efficiently stimulate hTERT-specific CTLs from human peripheral blood T lymphocytes and suggest that sufficient expansion could be achieved to be clinically useful for adoptive cell therapy.

  16. 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...

  17. 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.

  18. 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

  19. 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.

  20. 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.

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

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    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.

  2. 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

  3. Immune tolerance maintained by cooperative interactions between T cells and antigen presenting cells shapes a diverse TCR repertoire

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    Katharine eBest

    2015-08-01

    Full Text Available The T cell population in an individual needs to avoid harmful activation by self-peptides while maintaining the ability to respond to an unknown set of foreign peptides. This property is acquired by a combination of thymic and extra-thymic mechanisms. We extend current models for the development of self/non-self discrimination to consider the acquisition of self-tolerance as an emergent system level property of the overall T cell receptor repertoire. We propose that tolerance is established at the level of the antigen presenting cell/T cell cluster, which facilitates and integrates co-operative interactions between T cells of different specificity. The threshold for self-reactivity is therefore imposed at a population level, and not at the level of the individual T cell/antigen encounter. Mathematically, the model can be formulated as a linear programming optimisation problem, which can be implemented as a multiplicative update algorithm which shows a rapid convergence to a stable state. The model constrains self-reactivity within a predefined threshold, but maintains the diversity and cross reactivity which are key characteristics of human T cell immunity. We show further that the size of individual clones in the model repertoire remains heterogeneous, and that new clones can establish themselves even when the repertoire is stable. Our study combines the salient features of the danger model of self/non-self discrimination with the concepts of quorum sensing, and extends repertoire generation models to encompass the establishment of tolerance. Furthermore, the dynamic and continuous repertoire reshaping which underlies tolerance in this model suggests opportunities for therapeutic intervention to achieve long-term tolerance following transplantation.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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 ...

  9. Tubulin and actin interplay at the T cell and Antigen-presenting cell interface

    Directory of Open Access Journals (Sweden)

    Noa B Martín-Cófreces

    2011-07-01

    Full Text Available T cells reorganize their actin and tubulin-based cytoskeletons to provide a physical basis to the immune synapse. However, growing evidence shows that their roles on T cell activation are more dynamic than merely serving as tracks or scaffold for different molecules. The cross-talk between both skeletons may be important for the formation and movement of the lamella at the IS by increasing the adhesion of the T cell to the APC, thus favoring the transport of components towards the plasma membrane and in turn regulating the T-APC intercellular communication. Microtubules and F-actin appear to be essential for the transport of the different signaling microclusters along the membrane, therefore facilitating the propagation of the signal. Finally, they can also be important for regulating the endocytosis, recycling and degradation of the TCR signaling machinery, thus helping both to sustain the activated state and to switch it off.

  10. 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

  11. Establishment and Characterization of a Cell Based Artificial Antigen-Presenting Cell for Expansion and Activation of CD8+ T Cells Ex Vivo

    Institute of Scientific and Technical Information of China (English)

    Weijuan Gong; Mingchun Ji; Zhengfeng Cao; Liheng Wang; Yayun Qian; Maozhi Hu; Li Qian; Xingyuan Pan

    2008-01-01

    Atificial antigen-presenting cells are expected to stimulate the expansion and acquisition of optimal therapeutic features of T cells before infusion. Here CD32 that binds to a crystallizable fragment of IgG monoclonal antibody was genetically expressed on human K562 leukemia cells to provide a ligand for T-cell receptor. CD86 and 4-1BBL, which are ligands of CO. stimulating receptors of CD28 and 4-1BB. respectively, were also expressed on K562 cells. Then we accomplished the artificial antigen-presenting cells by coupling K32, CD86/4-IBBL cell with OKT3 monoclonal antibody against CD3.named K32/CD86/4-lBBL/OKT3 cells. These artificial modified cells had the abilities of inducing CD8+ T cell activation. promoting CD8+ T cell proliferation, division, and long-term growth, inhibiting CD8+ T cell apoptosis, and enhancing CD8+ T cell secretion of IFN-Y and perforin. Furthermore, antigen. secific cytotoxic T lymphocytes could be retained in the culture stimulated with K32/CD86/4-1BBL/OKT3 cells at least within 28 day This approach was robust, simple, reproducible and economical for expansion and activation of CD8+ T cells and may have important therapeutic implications for adoptive immunotherapy. Cellular & Molecular Immunology.2007;5(1):47-53.

  12. 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.

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

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    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.

  14. 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

  15. 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.

  16. 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

  17. Probiotic metabolites from Bacillus coagulans GanedenBC30TM support maturation of antigen-presenting cells in vitro

    Institute of Scientific and Technical Information of China (English)

    Kathleen F Benson; Kimberlee A Redman; Steve G Carter; David Keller; Sean Farmer; John R Endres; Gitte S Jensen

    2012-01-01

    AIM:To study the effects of probiotic metabolites on maturation stage of antigen-presenting immune cells.METHODS:Ganeden Bacillus coagulans 30 (GBC30)bacterial cultures in log phase were used to isolate the secreted metabolite (MET) fraction.A second fraction was made to generate a crude cell-wall-enriched fraction,by centrifugation and lysis,followed by washing.A preparation of MET was subjected to size exclusion centrifugation,generating three fractions:< 3 kDa,3-30 kDa,and 30-200 kDa and activities were tested in comparison to crude MET and cell wall in primary cultures of human peripheral blood mononuclear cell (PBMC) as a source of antigen-presenting mononuclear phagocytes.The maturation status of mononudear phagocytes was evaluated by staining with monoclonal antibodies towards CD14,CD16,CD80 and CD86 and analyzed by flow cytometry.RESULTS:Treatment of PBMC with MET supported maturation of mononuclear phagocytes toward both macrophage and dendritic cell phenotypes.The biological activity unique to the metabolites included a reduction of CD14+ CD16+ pro-inflammatory ceils,and this property was associated with the high molecular weight metabolite fraction.Changes were also seen for the dendritic cell maturation markers CD80 and CD86.On CD14dim cells,an increase in both CD80 and CD86 expression was seen,in contrast to a selective increase in CD86 expression on CD14bright cells.The co-expression of CD80 and CD86 indicates effective antigen presentation to T cells and support of T helper cell differentiation.The selective expression of CD86 in the absence of CD80 points to a role in generating T regulatory cells.CONCLUSION:The data show that a primary mechanism of action of GBC30 metabolites involves support of more mature phenotypes of antigen-presenting cells,important for immunological decision-making.

  18. Malassezia yeasts activate the NLRP3 inflammasome in antigen-presenting cells via Syk-kinase signalling.

    Science.gov (United States)

    Kistowska, Magdalena; Fenini, Gabriele; Jankovic, Dragana; Feldmeyer, Laurence; Kerl, Katrin; Bosshard, Philipp; Contassot, Emmanuel; French, Lars E

    2014-12-01

    Although being a normal part of the skin flora, yeasts of the genus Malassezia are associated with several common dermatologic conditions including pityriasis versicolour, seborrhoeic dermatitis (SD), folliculitis, atopic eczema/dermatitis (AE/AD) and dandruff. While Malassezia spp. are aetiological agents of pityriasis versicolour, a causal role of Malassezia spp. in AE/AD and SD remains to be established. Previous reports have shown that fungi such as Candida albicans and Aspergillus fumigatus are able to efficiently activate the NLRP3 inflammasome leading to robust secretion of the pro-inflammatory cytokine IL-1β. To date, innate immune responses to Malassezia spp. are not well characterized. Here, we show that different Malassezia species could induce NLRP3 inflammasome activation and subsequent IL-1β secretion in human antigen-presenting cells. In contrast, keratinocytes were not able to secrete IL-1β when exposed to Malassezia spp. Moreover, we demonstrate that IL-1β secretion in antigen-presenting cells was dependent on Syk-kinase signalling. Our results identify Malassezia spp. as potential strong inducers of pro-inflammatory responses when taken up by antigen-presenting cells and identify C-type lectin receptors and the NLRP3 inflammasome as crucial actors in this process. PMID:25267545

  19. Liver dendritic cells present bacterial antigens and produce cytokines upon Salmonella encounter.

    Science.gov (United States)

    Johansson, Cecilia; Wick, Mary Jo

    2004-02-15

    The capacity of murine liver dendritic cells (DC) to present bacterial Ags and produce cytokines after encounter with Salmonella was studied. Freshly isolated, nonparenchymal liver CD11c(+) cells had heterogeneous expression of MHC class II and CD11b and a low level of CD40 and CD86 expression. Characterization of liver DC subsets revealed that CD8alpha(-)CD4(-) double negative cells constituted the majority of liver CD11c(+) ( approximately 85%) with few cells expressing CD8alpha or CD4. Flow cytometry analysis of freshly isolated CD11c(+) cells enriched from the liver and cocultured with Salmonella expressing green fluorescent protein (GFP) showed that CD11c(+) MHC class II(high) cells had a greater capacity to internalize Salmonella relative to CD11c(+) MHC class II(low) cells. Moreover, both CD8alpha(-) and CD8alpha(+) liver DC internalized bacteria with similar efficiency after both in vitro and in vivo infection. CD11c(+) cells enriched from the liver could also process Salmonella for peptide presentation on MHC class I and class II to primary, Ag-specific T cells after internalization requiring actin cytoskeletal rearrangements. Flow cytometry analysis of liver CD11c(+) cells infected with Salmonella expressing GFP showed that both CD8alpha(-) and CD8alpha(+) DC produced IL-12p40 and TNF-alpha. The majority of cytokine-positive cells did not contain bacteria (GFP(-)) whereas only a minor fraction of cytokine-positive cells were GFP(+). Furthermore, only approximately 30-50% of liver DC containing bacteria (GFP(+)) produced cytokines. Thus, liver DC can internalize and process Salmonella for peptide presentation to CD4(+) and CD8(+) T cells and elicit proinflammatory cytokine production upon Salmonella encounter, suggesting that DC in the liver may contribute to immunity against hepatotropic bacteria.

  20. Properties of glycolipid-enriched membrane rafts in antigen presentation.

    Science.gov (United States)

    Rodgers, William; Smith, Kenneth

    2005-01-01

    Presentation of antigen to T cells represents one of the central events in the engagement of the immune system toward the defense of the host against pathogens. Accordingly, understanding the mechanisms by which antigen presentation occurs is critical toward our understanding the properties of host defense against foreign antigen, as well as insight into other features of the immune system, such as autoimmune disease. The entire antigen-presentation event is complex, and many features of it remain poorly understood. However, recent studies have provided evidence showing that glycolipid-enriched membrane rafts are important for efficient antigen presentation; the studies suggest that one such function of rafts is trafficking of antigen-MHC II complexes to the presentation site on the surface of the antigen-presenting cell. Here, we present a critical discussion of rafts and their proposed functions in antigen presentation. Emerging topics of rafts and antigen presentation that warrant further investigation are also highlighted.

  1. 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

  2. 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.

  3. 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...

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. ESAT-6 Targeting to DEC205+ Antigen Presenting Cells Induces Specific-T Cell Responses against ESAT-6 and Reduces Pulmonary Infection with Virulent Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Aarón Silva-Sánchez

    Full Text Available Airways infection with Mycobacterium tuberculosis (Mtb is contained mostly by T cell responses, however, Mtb has developed evasion mechanisms which affect antigen presenting cell (APC maturation/recruitment delaying the onset of Ag-specific T cell responses. Hypothetically, bypassing the natural infection routes by delivering antigens directly to APCs may overcome the pathogen's naturally evolved evasion mechanisms, thus facilitating the induction of protective immune responses. We generated a murine monoclonal fusion antibody (α-DEC-ESAT to deliver Early Secretory Antigen Target (ESAT-6 directly to DEC205+ APCs and to assess its in vivo effects on protection associated responses (IFN-γ production, in vivo CTL killing, and pulmonary mycobacterial load. Treatment with α-DEC-ESAT alone induced ESAT-6-specific IFN-γ producing CD4+ T cells and prime-boost immunization prior to Mtb infection resulted in early influx (d14 post-infection and increased IFN-γ+ production by specific T cells in the lungs, compared to scarce IFN-γ production in control mice. In vivo CTL killing was quantified in relevant tissues upon transferring target cells loaded with mycobacterial antigens. During infection, α-DEC-ESAT-treated mice showed increased target cell killing in the lungs, where histology revealed cellular infiltrate and considerably reduced bacterial burden. Targeting the mycobacterial antigen ESAT-6 to DEC205+ APCs before infection expands specific T cell clones responsible for early T cell responses (IFN-γ production and CTL activity and substantially reduces lung bacterial burden. Delivering mycobacterial antigens directly to APCs provides a unique approach to study in vivo the role of APCs and specific T cell responses to assess their potential anti-mycobacterial functions.

  12. 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)

    Robert E.Humphreys; Gilda G.Hillman; Eric von Hofe; Minzhen Xu

    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.

  13. 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.

  14. Tumor Destruction and In Situ Delivery of Antigen Presenting Cells Promote Anti-Neoplastic Immune Responses: Implications for the Immunotherapy of Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Manfredi AA

    2004-07-01

    Full Text Available Antigen presenting cells (APCs activate helper and cytotoxic T cells specific for antigens expressed by tissue cells, including neoplastic cells. This event occurs after the antigen transfer from tissue cells to APC, and is referred to as "cross-presentation". The number and the state of activation of APC in the tumor control the outcome of cross-presentation, including the establishment of protective immune responses. Cell death favors cross-presentation. Cancer cells normally die, either spontaneously or as a consequence of targeted therapies. The transfer of tumor antigens from dying tumor cells to APCs in vivo, exploiting the cross-presentation pathway, has the potential of yielding novel immunotherapeutic strategies. Their success will depend on at least two factors: the induction of synchronized cell death in the tumor, and the recruitment of activated dendritic cells in the tumor. Under normal conditions, pancreatic cancer represents a privileged environment; its profound chemoresistance reflects limited apoptosis after chemotherapy. Moreover, it usually contains only a few cells endowed with APC function. Endoscopic ultrasonography offers attractive possibilities of circumventing this privilege, including the delivery of ultrasound, radiofrequency or radiation in order to destroy the tumor and the delivery in situ of autologous APC or appropriate chemotactic signals. In general, loco-regional approaches offer the possibility of using the tumor of each patient as a complex antigen source, thus limiting the risk of tumor escape and reducing the need for extensive ex vivo handling of the neoplasm and of the patient APCs.

  15. Transfection of B7-1 cDNA empowers antigen presentation of blood malignant cells for activation of anti-tumor T cells

    Institute of Scientific and Technical Information of China (English)

    克晓燕; 贾丽萍; 王晶; 王德炳

    2003-01-01

    Objective To define roles of B7-1 co-stimulation factor expressed in human malignant cell lines in mediating anti-tumor T cell immune responses. Methods Examining human leucocyte antigen (HLA) and B7 expressions on 8 human blood malignancies cell lines by flow cytometry. Transfecting B7-1 gene to B7-1 negative (B7*!-) Raji and B7*!- Jurkat cell lines by liposome, and comparing the potencies of blood malignant cell lines in the induction of T cell activation by examination of T cell cytokine mRNAs before and after transfection using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). Results High level of HLA Ⅰ and Ⅱ molecules were expressed in most human blood malignant cell lines examined, and the co-stimulatory factor B7-2 was also highly expressed. In contrast, another member of B7 family: B7-1 was either not expressed or very limitedly expressed in most of these hematopoietic malignant cell lines. Most importantly, transfection of B7-1 gene to B7*!-. Raji and B7*!-. Jurkat cell lines made these cell lines better antigen presenting cells for stimulation of anti-tumor T cell activation, which was demonstrated by up regulation of expression of T cell cytokines IL-2, IL-4 and INF-γ mRNAs after incubation of these tumor cells with T cells for 24 h. Conclusions B7 co-stimulation plays an important role in anti-tumor immunity. Transfection of B7-1 gene to the human hematopoietic malignant cell lines that are deficient in the B7-1 expression empowers their antigen presentation potency for activation of anti-tumor T cells. Our results suggested that repairing the deficiency of B7-1 co-stimulatory pathway in tumor cells might be a novel immunotherapeutic approach for human hematopoietic malignancies.

  16. The Plasticity of γδT Cells: Innate Immunity, Antigen Presentation and New Immunotherapy

    Institute of Scientific and Technical Information of China (English)

    Rita Casetti; Angelo Martino

    2008-01-01

    Several signals influence dendritic cell (DC) functions and consequent the immune responses to infectious pathogens. Our recent findings provide a new model of intervention on DCs implicating human γδ T cell stimuli. Vγ9Vδ2 T cells represent the major subset of circulating human γδ T cells and can be activated by non-peptidic molecules derived from different microorganisms or abnormal metabolic routes. With activated-Vγ9Vδ2 T cell co-culture, immature DCs acquire features of mature DCs, such as increasing the migratory activity, up-regulating the chemokine receptors, and triggering the Thl immune response. Similar to the NK-derived signals, DC activation is mediated by soluble factors as well as cell-to-cell contact. Many non-peptidic molecules including nitrogen- containing bisphosphonates and pyrophosphomonoester drugs, can stimulate the activity of Vγ9Vδ2 T cells in vitro and in vivo. The relatively low in vivo toxicity of many of these drugs makes possible novel vaccine and immune-based strategies against infectious diseases. Cellular & Molecular Immunology. 2008;5(3):161-170.

  17. Keratinocytes Function as Accessory Cells for Presentation of Endogenous Antigen Expressed in the Epidermis

    NARCIS (Netherlands)

    B.S. Kim; F. Miyagawa; Y.H. Cho; C.L. Bennett; B.E. Clausen; S.I. Katz

    2009-01-01

    The precise contribution(s) of skin dendritic cells (DCs) to immune responses in the skin has not been well delineated. We developed an intradermal (i.d.) injection model in which CD8(+) T (OT-I) cells that express ovalbumin (OVA) peptide-specific TCRs (V alpha 2/V beta 5) are delivered directly to

  18. Defects in Antigen-Presenting Cells in the BB-DP Rat Model of Diabetes

    NARCIS (Netherlands)

    V. Sommandas (Vinod)

    2008-01-01

    textabstractType-1 diabetes is the result of a T cell mediated immune response against the insulin-producing β cells in the islet of Langerhans. In humans, until now, the disease is only clearly detectable at the onset of the disease. Therefore studies to identify initial factors involved in

  19. Sinks, suppressors and antigen presenters: how lymphodepletion enhances T cell-mediated tumor immunotherapy

    OpenAIRE

    Klebanoff, Christopher A.; Khong, Hung T.; Antony, Paul A.; Douglas C Palmer; Restifo, Nicholas P

    2005-01-01

    Lymphodepletion followed by adoptive cell transfer (ACT) of autologous, tumor-reactive T cells boosts antitumor immunotherapeutic activity in mouse and in humans. In the most recent clinical trials, lymphodepletion together with ACT has an objective response rate of 50% in patients with solid metastatic tumors. The mechanisms underlying this recent advance in cancer immunotherapy are beginning to be elucidated and include: the elimination of cellular cytokine ‘sinks’ for homeostatic γC-cytoki...

  20. Antigen presenting B cells facilitate CD4 T cell cooperation resulting in enhanced generation of effector and memory CD4 T cells.

    Directory of Open Access Journals (Sweden)

    David R Kroeger

    Full Text Available We show that the in vivo generation of cytokine-producing CD4 T cells specific for a given major histocompatibility class-II (MHCII-binding peptide of hen egg lysozyme (HEL is facilitated when mice are immunized with splenic antigen presenting cells (APC pulsed with this HEL peptide and another peptide that binds a different MHCII molecule. This enhanced generation of peptide-specific effector CD4 T cells requires that the same splenic APC be pulsed with both peptides. Pulsed B cells, but not pulsed dendritic cells (DCs, can mediate CD4 T cell cooperation, which can be blocked by disrupting OX40-OX40L (CD134-CD252 interactions. In addition, the generation of HEL peptide-specific CD4 T cell memory is greater when mice are primed with B cells pulsed with the two peptides than with B cells pulsed with the HEL- peptide alone. Based on our findings, we suggest CD4 T cell cooperation is important for vaccine design, underlies the phenomenon of "epitope-spreading" seen in autoimmunity, and that the efficacy of B cell-depletion in the treatment of human cell-mediated autoimmune disease is due to the abrogation of the interactions between autoimmune CD4 T cells that facilitates their activation.

  1. Minimum information about tolerogenic antigen-presenting cells (MITAP): a first step towards reproducibility and standardisation of cellular therapies.

    Science.gov (United States)

    Lord, Phillip; Spiering, Rachel; Aguillon, Juan C; Anderson, Amy E; Appel, Silke; Benitez-Ribas, Daniel; Ten Brinke, Anja; Broere, Femke; Cools, Nathalie; Cuturi, Maria Cristina; Diboll, Julie; Geissler, Edward K; Giannoukakis, Nick; Gregori, Silvia; van Ham, S Marieke; Lattimer, Staci; Marshall, Lindsay; Harry, Rachel A; Hutchinson, James A; Isaacs, John D; Joosten, Irma; van Kooten, Cees; Lopez Diaz de Cerio, Ascension; Nikolic, Tatjana; Oral, Haluk Barbaros; Sofronic-Milosavljevic, Ljiljana; Ritter, Thomas; Riquelme, Paloma; Thomson, Angus W; Trucco, Massimo; Vives-Pi, Marta; Martinez-Caceres, Eva M; Hilkens, Catharien M U

    2016-01-01

    Cellular therapies with tolerogenic antigen-presenting cells (tolAPC) show great promise for the treatment of autoimmune diseases and for the prevention of destructive immune responses after transplantation. The methodologies for generating tolAPC vary greatly between different laboratories, making it difficult to compare data from different studies; thus constituting a major hurdle for the development of standardised tolAPC therapeutic products. Here we describe an initiative by members of the tolAPC field to generate a minimum information model for tolAPC (MITAP), providing a reporting framework that will make differences and similarities between tolAPC products transparent. In this way, MITAP constitutes a first but important step towards the production of standardised and reproducible tolAPC for clinical application. PMID:27635311

  2. Minimum information about tolerogenic antigen-presenting cells (MITAP): a first step towards reproducibility and standardisation of cellular therapies

    Science.gov (United States)

    Spiering, Rachel; Aguillon, Juan C.; Anderson, Amy E.; Appel, Silke; Benitez-Ribas, Daniel; ten Brinke, Anja; Broere, Femke; Cools, Nathalie; Cuturi, Maria Cristina; Diboll, Julie; Geissler, Edward K.; Giannoukakis, Nick; Gregori, Silvia; van Ham, S. Marieke; Lattimer, Staci; Marshall, Lindsay; Harry, Rachel A.; Hutchinson, James A.; Isaacs, John D.; Joosten, Irma; van Kooten, Cees; Lopez Diaz de Cerio, Ascension; Nikolic, Tatjana; Oral, Haluk Barbaros; Sofronic-Milosavljevic, Ljiljana; Ritter, Thomas; Riquelme, Paloma; Thomson, Angus W.; Trucco, Massimo; Vives-Pi, Marta; Martinez-Caceres, Eva M.

    2016-01-01

    Cellular therapies with tolerogenic antigen-presenting cells (tolAPC) show great promise for the treatment of autoimmune diseases and for the prevention of destructive immune responses after transplantation. The methodologies for generating tolAPC vary greatly between different laboratories, making it difficult to compare data from different studies; thus constituting a major hurdle for the development of standardised tolAPC therapeutic products. Here we describe an initiative by members of the tolAPC field to generate a minimum information model for tolAPC (MITAP), providing a reporting framework that will make differences and similarities between tolAPC products transparent. In this way, MITAP constitutes a first but important step towards the production of standardised and reproducible tolAPC for clinical application. PMID:27635311

  3. Aedes aegypti saliva alters leukocyte recruitment and cytokine signaling by antigen-presenting cells during West Nile virus infection.

    Directory of Open Access Journals (Sweden)

    Bradley S Schneider

    Full Text Available West Nile virus (WNV is transmitted during mosquito bloodfeeding. Consequently, the first vertebrate cells to contact WNV are cells in the skin, followed by those in the draining lymph node. Macrophages and dendritic cells are critical early responders in host defense against WNV infection, not just because of their role in orchestrating the immune response, but also because of their importance as sites of early peripheral viral replication. Antigen-presenting cell (APC signals have a profound effect on host antiviral responses and disease severity. During transmission, WNV is intimately associated with mosquito saliva. Due to the ability of mosquito saliva to affect inflammation and immune responses, and the importance of understanding early events in WNV infection, we investigated whether mosquito saliva alters APC signaling during arbovirus infection, and if alterations in cell recruitment occur when WNV infection is initiated with mosquito saliva. Accordingly, experiments were performed with cultured dendritic cells and macrophages, flow cytometry was used to characterize infiltrating cell types in the skin and lymph nodes during early infection, and real-time RT-PCR was employed to evaluate virus and cytokine levels. Our in vitro results suggest that mosquito saliva significantly decreases the expression of interferon-beta and inducible nitric oxide synthase in macrophages (by as much as 50 and 70%, respectively, whilst transiently enhancing interleukin-10 (IL-10 expression. In vivo results indicate that the predominate effect of mosquito feeding is to significantly reduce the recruitment of T cells, leading the inoculation site of mice exposed to WNV alone to have up to 2.8 fold more t cells as mice infected in the presence of mosquito saliva. These shifts in cell population are associated with significantly elevated IL-10 and WNV (up to 4.0 and 10 fold, respectively in the skin and draining lymph nodes. These results suggest that mosquito

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

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Zeuthen, Louise Hjerrild; Ferlazzo, Guido;

    2007-01-01

    (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......, 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...

  5. Epigenetic regulations in the IFNγ signalling pathway: IFNγ-mediated MHC class I upregulation on tumour cells is associated with DNA demethylation of antigen-presenting machinery genes.

    Science.gov (United States)

    Vlková, Veronika; Štěpánek, Ivan; Hrušková, Veronika; Šenigl, Filip; Mayerová, Veronika; Šrámek, Martin; Šímová, Jana; Bieblová, Jana; Indrová, Marie; Hejhal, Tomáš; Dérian, Nicolas; Klatzmann, David; Six, Adrien; Reiniš, Milan

    2014-08-30

    Downregulation of MHC class I expression on tumour cells, a common mechanism by which tumour cells can escape from specific immune responses, can be associated with coordinated silencing of antigen-presenting machinery genes. The expression of these genes can be restored by IFNγ. In this study we documented association of DNA demethylation of selected antigen-presenting machinery genes located in the MHC genomic locus (TAP-1, TAP-2, LMP-2, LMP-7) upon IFNγ treatment with MHC class I upregulation on tumour cells in several MHC class I-deficient murine tumour cell lines (TC-1/A9, TRAMP-C2, MK16 and MC15). Our data also documented higher methylation levels in these genes in TC-1/A9 cells, as compared to their parental MHC class I-positive TC-1 cells. IFNγ-mediated DNA demethylation was relatively fast in comparison with demethylation induced by DNA methyltransferase inhibitor 5-azacytidine, and associated with increased histone H3 acetylation in the promoter regions of APM genes. Comparative transcriptome analysis in distinct MHC class I-deficient cell lines upon their treatment with either IFNγ or epigenetic agents revealed that a set of genes, significantly enriched for the antigen presentation pathway, was regulated in the same manner. Our data demonstrate that IFNγ acts as an epigenetic modifier when upregulating the expression of antigen-presenting machinery genes.

  6. 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.

  7. 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

  8. Artificial antigen-presenting cells plus IL-15 and IL-21 efficiently induce melanoma-specific cytotoxic CD8+CD28+ T lymphocyte responses

    Institute of Scientific and Technical Information of China (English)

    Xia Yu; Yuan Fang; Xi Li; Nuo Zhou; Yong-Xiang Zhao; Xiao-Ling Lu; Jian He; Sodaly Mongkhoune; Yi Peng; Yuan Xie; Jing Su; Su-Fang Zhou; Xiao-Xun Xie; Guo-Rong Luo

    2013-01-01

    To develop a novel artificial antigen-presenting system for efficiently inducing melanoma-specific CD8+CD28+ cytotoxic T lymphocyte (CTL) responses. Methods: Cell-sized Dynabeads® M-450 Epoxy beads coated with H-2Kb:Ig-TRP2180-188 and anti-CD28 antibody were used as artificial antigen-presenting cells (aAPCs) to induce melanoma-specific CD8+CD28+CTL responses with the help of IL-21 and IL-15. Dimer staining, proliferation, ELISPOT, and cytotoxicity experiments were conducted to evaluate the frequency and activity of induced CTLs. Results: Dimer staining demonstrated that the new artificial antigen-presenting system efficiently induced melanoma TRP2-specific CD8+CD28+ CTLs. Proliferation and ELISPOT assays indicated that the induced CTLs rapidly proliferate and produce increased IFN-γ under the stimulation of H-2Kb:Ig-TRP2-aAPCs, IL-15, and IL-21. In addition, cytotoxicity experiments showed that induced CTLs have specific killing activity of target cells. Conclusions: The new artificial antigen-presenting system including aAPCs plus IL-21 and IL-15 can induce a large number of antigen-specific CD8+CD28+ CTLs against the melanoma. Our study provides evidence for a novel adoptive immunotherapy against tumors.

  9. 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

  10. Understanding MHC class I presentation of viral antigens by human dendritic cells as a basis for rational design of therapeutic vaccines

    Directory of Open Access Journals (Sweden)

    Nadine eVan Montfoort

    2014-04-01

    Full Text Available Effective viral clearance requires the induction of virus-specific CD8+ cytotoxic T lymphocytes (CTL. Since dendritic cells (DC have a central role in initiating and shaping virus-specific CTL responses, it is important to understand how DC initiate virus-specific CTL responses. Some viruses can directly infect DC, which theoretically allows direct presentation of viral antigens to CTL, but many viruses target other cells than DC and thus the host depends on the cross-presentation of viral antigens by DC to activate virus-specific CTL.Research in mouse models has highly enhanced our understanding of the mechanisms underlying cross-presentation and the DC subsets involved, however, these results cannot be readily translated towards the role of human DC in MHC class I antigen presentation of human viruses. Here, we summarize the insights gained in the past 20 years on MHC class I presentation of viral antigen by human DC and add to the current debate on the capacities of different human DC subsets herein. Furthermore, possible sources of viral antigens and essential DC characteristics for effective induction of virus-specific CTL are evaluated.We conclude that cross-presentation is not only an efficient mechanism exploited by DC to initiate immunity to viruses that do not infect DC but also to viruses that do infect DC, because cross-presentation has many conceptual advantages and bypasses direct immune modulatory effects of the virus on its infected target cells. Since knowledge on the mechanism of viral antigen presentation and the preferred DC subsets is crucial for rational vaccine design, the obtained insights are very instrumental for the development of effective anti-viral immunotherapy.

  11. Ubiquitination by March-I prevents MHC class II recycling and promotes MHC class II turnover in antigen-presenting cells.

    Science.gov (United States)

    Cho, Kyung-Jin; Walseng, Even; Ishido, Satoshi; Roche, Paul A

    2015-08-18

    MHC class II (MHC-II)-dependent antigen presentation by antigen-presenting cells (APCs) is carefully controlled to achieve specificity of immune responses; the regulated assembly and degradation of antigenic peptide-MHC-II complexes (pMHC-II) is one aspect of such control. In this study, we have examined the role of ubiquitination in regulating pMHC-II biosynthesis, endocytosis, recycling, and turnover in APCs. By using APCs obtained from MHC-II ubiquitination mutant mice, we find that whereas ubiquitination does not affect pMHC-II formation in dendritic cells (DCs), it does promote the subsequent degradation of newly synthesized pMHC-II. Acute activation of DCs or B cells terminates expression of the MHC-II E3 ubiquitin ligase March-I and prevents pMHC-II ubiquitination. Most importantly, this change results in very efficient pMHC-II recycling from the surface of DCs and B cells, thereby preventing targeting of internalized pMHC-II to lysosomes for degradation. Biochemical and functional assays confirmed that pMHC-II turnover is suppressed in MHC-II ubiquitin mutant DCs or by acute activation of wild-type DCs. These studies demonstrate that acute APC activation blocks the ubiquitin-dependent turnover of pMHC-II by promoting efficient pMHC-II recycling and preventing lysosomal targeting of internalized pMHC-II, thereby enhancing pMHC-II stability for efficient antigen presentation to CD4 T cells.

  12. A Role For Mitochondria In Antigen Processing And Presentation.

    Science.gov (United States)

    Bonifaz, Lc; Cervantes-Silva, Mp; Ontiveros-Dotor, E; López-Villegas, Eo; Sánchez-García, Fj

    2014-09-23

    Immune synapse formation is critical for T lymphocyte activation, and mitochondria have a role in this process, by localizing close to the immune synapse, regulating intracellular calcium concentration, and providing locally required ATP. The interaction between antigen presenting cells (APCs) and T lymphocytes is a two-way signaling process. However, the role of mitochondria in antigen presenting cells during this process remains unknown. For APCs to be able to activate T lymphocytes, they must first engage in an antigen-uptake, -processing, and -presentation process. Here we show that HEL-loaded B lymphocytes, as a type of APCs, undergo a small but significant mitochondrial depolarization by 1-2 h following antigen exposure thus suggesting an increase in their metabolic demands. Inhibition of ATP synthase (oligomycin) or mitochondrial Ca(2+) uniporter (MCU) (Ruthenium red) had no effect on antigen uptake. Therefore, antigen processing and antigen presentation were further analyzed. Oligomycin treatment reduced the amount of specific MHC-peptide complexes but not total MHC II on the cell membrane of B lymphocytes which correlated with a decrease in antigen presentation. However, oligomycin also reduced antigen presentation by B lymphocytes that endogenously express HEL and by B lymphocytes loaded with the HEL48-62 peptide, although to a lesser extent. ATP synthase inhibition and MCU inhibition had a clear inhibitory effect on antigen processing (DQ-OVA). Taking together these results suggest that ATP synthase and MCU are relevant for antigen processing and presentation. Finally, APCs mitochondria were found to re-organize towards the APC-T immune synapse. This article is protected by copyright. All rights reserved.

  13. Antigen processing and remodeling of the endosomal pathway: requirements for antigen cross-presentation.

    Directory of Open Access Journals (Sweden)

    Ewoud Bernardus Compeer

    2012-03-01

    Full Text Available The cross-presentation of endocytosed antigen as peptide/class I MHC complexes plays a central role in the elicitation of CD8+ T cell clones that mediate anti-viral and anti-tumor immune responses. While it has been clear that there are specific subsets of professional antigen presenting cells (APC capable of antigen cross-presentation, description of mechanisms involved is still ongoing. Especially amongst dendritic cells (DC, there are specialized subsets that are highly proficient at antigen cross-presentation. We here present a focused survey on the cell biological processes in the endosomal pathway that support antigen cross-presentation. This review highlight DC-intrinsic mechanisms that facilitate the cross-presentation of endocytosed antigen, including receptor-mediated uptake, recycling and maturation including the sorting of membrane proteins, dynamic remodeling of endosomal structures and cell-surface directed endosomal trafficking. We will conclude with description of pathogen-induced deviation of endosomal processing, and discuss how immune evasion strategies pertaining endosomal trafficking may preclude antigen cross-presentation.

  14. 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

  15. Efficient targeting of protein antigen to the dendritic cell receptor DEC-205 in the steady state leads to antigen presentation on major histocompatibility complex class I products and peripheral CD8+ T cell tolerance.

    Science.gov (United States)

    Bonifaz, Laura; Bonnyay, David; Mahnke, Karsten; Rivera, Miguel; Nussenzweig, Michel C; Steinman, Ralph M

    2002-12-16

    To identify endocytic receptors that allow dendritic cells (DCs) to capture and present antigens on major histocompatibility complex (MHC) class I products in vivo, we evaluated DEC-205, which is abundant on DCs in lymphoid tissues. Ovalbumin (OVA) protein, when chemically coupled to monoclonal alphaDEC-205 antibody, was presented by CD11c+ lymph node DCs, but not by CD11c- cells, to OVA-specific, CD4+ and CD8+ T cells. Receptor-mediated presentation was at least 400 times more efficient than unconjugated OVA and, for MHC class I, the DCs had to express transporter of antigenic peptides (TAP) transporters. When alphaDEC-205:OVA was injected subcutaneously, OVA protein was identified over a 4-48 h period in DCs, primarily in the lymph nodes draining the injection site. In vivo, the OVA protein was selectively presented by DCs to TCR transgenic CD8+ cells, again at least 400 times more effectively than soluble OVA and in a TAP-dependent fashion. Targeting of alphaDEC-205:OVA to DCs in the steady state initially induced 4-7 cycles of T cell division, but the T cells were then deleted and the mice became specifically unresponsive to rechallenge with OVA in complete Freund's adjuvant. In contrast, simultaneous delivery of a DC maturation stimulus via CD40, together with alphaDEC-205:OVA, induced strong immunity. The CD8+ T cells responding in the presence of agonistic alphaCD40 antibody produced large amounts of interleukin 2 and interferon gamma, acquired cytolytic function in vivo, emigrated in large numbers to the lung, and responded vigorously to OVA rechallenge. Therefore, DEC-205 provides an efficient receptor-based mechanism for DCs to process proteins for MHC class I presentation in vivo, leading to tolerance in the steady state and immunity after DC maturation.

  16. Efficient Targeting of Protein Antigen to the Dendritic Cell Receptor DEC-205 in the Steady State Leads to Antigen Presentation on Major Histocompatibility Complex Class I Products and Peripheral CD8+ T Cell Tolerance

    Science.gov (United States)

    Bonifaz, Laura; Bonnyay, David; Mahnke, Karsten; Rivera, Miguel; Nussenzweig, Michel C.; Steinman, Ralph M.

    2002-01-01

    To identify endocytic receptors that allow dendritic cells (DCs) to capture and present antigens on major histocompatibility complex (MHC) class I products in vivo, we evaluated DEC-205, which is abundant on DCs in lymphoid tissues. Ovalbumin (OVA) protein, when chemically coupled to monoclonal αDEC-205 antibody, was presented by CD11c+ lymph node DCs, but not by CD11c− cells, to OVA-specific, CD4+ and CD8+ T cells. Receptor-mediated presentation was at least 400 times more efficient than unconjugated OVA and, for MHC class I, the DCs had to express transporter of antigenic peptides (TAP) transporters. When αDEC-205:OVA was injected subcutaneously, OVA protein was identified over a 4–48 h period in DCs, primarily in the lymph nodes draining the injection site. In vivo, the OVA protein was selectively presented by DCs to TCR transgenic CD8+ cells, again at least 400 times more effectively than soluble OVA and in a TAP-dependent fashion. Targeting of αDEC-205:OVA to DCs in the steady state initially induced 4–7 cycles of T cell division, but the T cells were then deleted and the mice became specifically unresponsive to rechallenge with OVA in complete Freund's adjuvant. In contrast, simultaneous delivery of a DC maturation stimulus via CD40, together with αDEC-205:OVA, induced strong immunity. The CD8+ T cells responding in the presence of agonistic αCD40 antibody produced large amounts of interleukin 2 and interferon γ, acquired cytolytic function in vivo, emigrated in large numbers to the lung, and responded vigorously to OVA rechallenge. Therefore, DEC-205 provides an efficient receptor-based mechanism for DCs to process proteins for MHC class I presentation in vivo, leading to tolerance in the steady state and immunity after DC maturation. PMID:12486105

  17. Distinct Gut-Derived Bacteria Differentially Affect Three Types of Antigen-Presenting Cells and Impact on NK- and T-Cell Responses

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Hansen, Anne Marie Valentin; Frøkiær, Hanne

    Objectives Gut bacteria are assumed essential for development and maintenance of a balanced immune system. Specifically, stimulation of antigen-presenting cells (APCs) by gut bacteria is important for polarisation of the immune response. This experiment was designed to reveal similarities...... from monocytes. Monocyte-derived dendritic cells constitute a commonly used model of dendritic cell function. The APCs were cultured for 18 h with four different gut bacteria: Lactobacillus acidophilus X37, Lactobacillus reuteri DSM 12246, E. coli Nissle 1917 or Bifidobacterium longum Q46. Results...... & Discussion To examine the polarising effect of gut bacteria on APCs, surface markers and cytokines were measured. The co-stimulatory molecules CD40 and CD86 were induced to a different extent together with CD83. Interleukin-12 (a Th1 cytokine) was only induced by Lactobacillus acidophilus. Interleukin-10...

  18. 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...

  19. 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

  20. Availability of 25-hydroxyvitamin D3 to antigen presenting cells controls the balance between regulatory and inflammatory T cell responses

    OpenAIRE

    Jeffery, Louisa E.; Wood, Alice M; Qureshi, Omar S.; Hou, Tie Zheng; Gardner, David; Briggs, Zoe; Kaur, Satdip; Raza, Karim; Sansom, David M

    2012-01-01

    1,25-dihydroxyvitamin D3 (1,25(OH)2D3), the active form of vitamin D, exerts potent effects on several tissues including cells of the immune system, where it affects T cell activation, differentiation and migration. The circulating, inactive form of vitamin D, 25(OH)D3, is generally used as an indication of “vitamin D status”. However, utilization of this precursor depends on its uptake by cells and subsequent conversion by the enzyme 25(OH)D3-1α-hydroxylase (CYP27B1) into active 1,25(OH)2D3....

  1. 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

  2. Identification of the major T-cell antigens present in the Brucella melitensis B115 protein preparation, Brucellergene OCB.

    Science.gov (United States)

    Denoel, P A; Vo, T K; Weynants, V E; Tibor, A; Gilson, D; Zygmunt, M S; Limet, J N; Letesson, J J

    1997-09-01

    Brucellergene is a commercial allergen prepared from Brucella melitensis strain B115 and containing at least 20 cytoplasmic proteins. These proteins were separated by SDS-PAGE. The unstained gel was divided into 18 fractions and proteins were eluted from the gel fractions. The capacity of the separated proteins to elicit delayed-type hypersensitivity (DTH) in infected guinea-pigs or to induce the production of interferon-gamma (IFN-gamma) by blood cells from infected cattle was evaluated. The biological activity of the corresponding protein fractions blotted on to nitrocellulose was measured in a lymphocyte blastogenesis assay. Among the 18 fractions tested, two-spanning the mol. wt ranges 17-22 (fraction 8) and 35-42-kDa (fraction 17)-showed the maximum biological activity in the three tests. These fractions contain two antigens, the Brucella bacterioferritin (BFR) and P39 proteins. Both proteins are good candidates for the detection of cellular immunity to Brucella. PMID:9291893

  3. 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.

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

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    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

  5. 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...

  6. Suppressive effects of Bifidobacterium longum on the production of Th2-attracting chemokines induced with T cell-antigen-presenting cell interactions.

    Science.gov (United States)

    Iwabuchi, Noriyuki; Takahashi, Noritoshi; Xiao, Jin-Zhong; Yonezawa, Sumiko; Yaeshima, Tomoko; Iwatsuki, Keiji; Hachimura, Satoshi

    2009-04-01

    In human trials, Bifidobacterium longum BB536 alleviates subjective symptoms of Japanese cedar pollinosis, an IgE-mediated type I allergy caused by exposure to Japanese cedar, and significantly suppresses the increase of plasma thymus- and activation-regulated chemokine (TARC) associated with pollen dispersion. In the present study, we investigated the suppressive effects of BB536 on the production of T helper type 2 (Th2)-attracting chemokines, such as TARC and macrophage-derived chemokine (MDC), together with the mechanisms of their production. Murine splenocytes were cultured with heat-killed BB536, and the levels of Th2-attracting chemokines in the supernatants were measured. TARC and MDC were produced in cultures without stimulation, and the production was significantly suppressed by BB536. These chemokines were produced by antigen-presenting cells (APCs) of splenocytes stimulated with an anti-CD40 antibody. Furthermore, TARC production was induced with granulocyte macrophage colony-stimulating factor that was produced by T cells and dendritic cells. BB536 suppressed MDC production induced with the anti-CD40 antibody by APCs from the spleen, mesenteric lymph nodes (MLNs) and Peyer's patches, and it suppressed TARC production by APCs from the spleen and MLNs. These results indicate that BB536 suppresses the production of Th2-attracting chemokines induced by the T cell-APC interaction, suggesting a novel mechanism for alleviating symptoms of allergic disorders by probiotics.

  7. 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)

  8. A novel HLA-B18 restricted CD8+ T cell epitope is efficiently cross-presented by dendritic cells from soluble tumor antigen.

    Directory of Open Access Journals (Sweden)

    Rona Y Zhao

    Full Text Available NY-ESO-1 has been a major target of many immunotherapy trials because it is expressed by various cancers and is highly immunogenic. In this study, we have identified a novel HLA-B*1801-restricted CD8(+ T cell epitope, NY-ESO-1(88-96 (LEFYLAMPF and compared its direct- and cross-presentation to that of the reported NY-ESO-1(157-165 epitope restricted to HLA-A*0201. Although both epitopes were readily cross-presented by DCs exposed to various forms of full-length NY-ESO-1 antigen, remarkably NY-ESO-1(88-96 is much more efficiently cross-presented from the soluble form, than NY-ESO-1(157-165. On the other hand, NY-ESO-1(157-165 is efficiently presented by NY-ESO-1-expressing tumor cells and its presentation was not enhanced by IFN-γ treatment, which induced immunoproteasome as demonstrated by Western blots and functionally a decreased presentation of Melan A(26-35; whereas NY-ESO-1(88-96 was very inefficiently presented by the same tumor cell lines, except for one that expressed high level of immunoproteasome. It was only presented when the tumor cells were first IFN-γ treated, followed by infection with recombinant vaccinia virus encoding NY-ESO-1, which dramatically increased NY-ESO-1 expression. These data indicate that the presentation of NY-ESO-1(88-96 is immunoproteasome dependent. Furthermore, a survey was conducted on multiple samples collected from HLA-B18(+ melanoma patients. Surprisingly, all the detectable responses to NY-ESO-1(88-96 from patients, including those who received NY-ESO-1 ISCOMATRIX™ vaccine were induced spontaneously. Taken together, these results imply that some epitopes can be inefficiently presented by tumor cells although the corresponding CD8(+ T cell responses are efficiently primed in vivo by DCs cross-presenting these epitopes. The potential implications for cancer vaccine strategies are further discussed.

  9. 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

  10. 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.

  11. 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

  12. Novel CD47: SIRPα dependent mechanism for the activation of STAT3 in antigen-presenting cell.

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    Natan Toledano

    Full Text Available Cell surface CD47 interacts with its receptor, signal-regulatory-protein α (SIRPα that is expressed predominantly on macrophages, to inhibit phagocytosis of normal, healthy cells. This "don't eat me" signal is mediated through tyrosine phosphorylation of SIRPα at the cytoplasmic ITIM motifs and the recruitment of the phosphatase, SHP-1. We previously revealed a novel mechanism for the activation of the STAT3 pathway and the regulation of human APC maturation and function that is based on cell:cell interaction. In this study, we present evidence supporting the notion that CD47:SIRPα serves as a cell surface receptor: ligand pair involved in this contact-dependent STAT3 activation and regulation of APC maturation. We show that upon co-culturing APC with various primary and tumor cell lines STAT3 phosphorylation and IL-10 expression are induced, and such regulation could be suppressed by specific CD47 siRNAs and shRNAs. Significantly, >50% reduction in CD47 expression abolished the contact-dependent inhibition of T cell activation. Furthermore, co-immunoprecipitation experiments revealed a physical association between SIRPα and STAT3. Thus, we suggest that in addition to signaling through the ITIM-SHP-1 complex that transmit an anti-phagocytotic, CD47:SIRPα also triggers STAT3 signaling that is linked to an immature APC phenotype and peripheral tolerance under steady state and pathological conditions.

  13. 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

  14. Rapid detection of dendritic cell and monocyte disorders using CD4 as a lineage marker of the human peripheral blood antigen presenting cell compartment

    Directory of Open Access Journals (Sweden)

    Laura eJardine

    2013-12-01

    Full Text Available Dendritic cells (DCs and monocytes are critical regulators and effectors of innate and adaptive immune responses. Monocyte expansion has been described in many pathological states while monocyte and DC deficiency syndromes are relatively recent additions to the catalogue of human primary immunodeficiency disorders. Clinically applicable screening tests to diagnose and monitor these conditions are lacking. Conventional strategies for identifying human DCs and monocytes have been based on the use of a lineage gate to exclude lymphocytes, thus preventing simultaneous detection of DCs, monocytes and lymphocyte subsets. Here we demonstrate that CD4 is a reliable lineage marker for the human peripheral blood antigen presenting cell compartment that can be used to identify DCs and monocytes in parallel with lymphocytes. Based on this principle, simple modification of a standard lymphocyte phenotyping assay permits simultaneous enumeration of four lymphocyte and five DC/monocyte populations from a single sample. This approach is applicable to clinical samples and facilitates the diagnosis of DC and monocyte disorders in a wide range of clinical settings, including genetic deficiency, neoplasia and inflammation.

  15. 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-cell

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

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    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.

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

    Directory of Open Access Journals (Sweden)

    Yu Cong

    2016-05-01

    Full Text Available 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.

  18. Induction of antigen-presenting capacity in tumor cells upon infection with non-replicating recombinant vaccinia virus encoding murine MHC class II and costimulatory molecules.

    Science.gov (United States)

    Marti, W R; Oertli, D; Meko, J B; Norton, J A; Tsung, K

    1997-01-15

    The possibility of inducing antigen-presenting capacity in cells normally lacking such capacity, currently represents a major goal in vaccine research. To address this issue we attempted to generate 'artificial' APC able to stimulate CD4+ T cell responses when tumor cells were infected with a single, recombinant, vaccinia virus (rVV) containing the two genes encoding murine MHC class II I-Ak and a third gene encoding the murine B7-1 (mB7-1) costimulatory molecule. To minimize the cytopathic effect and to improve safety, in view of possible in vivo applications, we made this rVV replication incompetent by Psoralen and long wave UV treatment. Tumor cells infected with rVV encoding I-Ak alone, pulsed with hen egg white lysozyme peptide (HEL46-61), induced IL-2 secretion by an antigen-specific T hybridoma. Tumor cells infected with the rVV encoding mB7-1 provided costimulation for activating resting CD4+ T cells in the presence of ConA. Tumor cells infected with the rVV encoding I-Ak and mB7-1, and pulsed with chicken ovotransferrin peptide (conalbumin133-145), induced a significantly higher response in a specific Th2 cell clone (D10.G4.1) as compared to cells infected with rVV encoding I-Ak molecules only. Thus, this replication incompetent rVV represents a safe, multiple gene, vector system able to confer in one single infection step effective APC capacity to non-professional APCs.

  19. 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....

  20. 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

  1. 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...

  2. Antigen-presenting cells represent targets for R5 HIV-1 infection in the first trimester pregnancy uterine mucosa.

    Directory of Open Access Journals (Sweden)

    Romain Marlin

    Full Text Available BACKGROUND: During the first trimester of pregnancy, HIV-1 mother-to-child transmission is relatively rare despite the permissivity of placental cells to cell-to-cell HIV-1 infection. The placenta interacts directly with maternal uterine cells (decidual cells but the physiological role of the decidua in the control of HIV-1 transmission and whether decidua could be a source of infected cells is unknown. METHODOLOGY/PRINCIPAL FINDINGS: To answer to this question, decidual mononuclear cells were exposed to HIV-1 in vitro. Decidual cells were shown to be more susceptible to infection by an R5 HIV-1, as compared to an X4 HIV-1. Infected cells were identified by flow cytometry analysis. The results showed that CD14(+ cells were the main targets of HIV-1 infection in the decidua. These infected CD14(+ cells expressed DC-SIGN, CD11b, CD11c, the Fc gamma receptor CD16, CD32 and CD64, classical MHC class-I and class-II and maturation and activation molecules CD83, CD80 and CD86. The permissivity of decidual tissue was also evaluated by histoculture. Decidual tissue was not infected by X4 HIV-1 but was permissive to R5 HIV-1. Different profiles of infection were observed depending on tissue localization. CONCLUSIONS/SIGNIFICANCE: The presence of HIV-1 target cells in the decidua in vitro and the low rate of in utero mother-to-child transmission during the first trimester of pregnancy suggest that a natural control occurs in vivo limiting cell-to-cell infection of the placenta and consequently infection of the fetus.

  3. Airway eosinophils accumulate in the mediastinal lymph nodes but lack antigen-presenting potential for naive T cells

    NARCIS (Netherlands)

    L.S. van Rijt (Leonie); N. Vos (Nanda); D. Hijdra; V.C. de Vries (Victor); H.C. Hoogsteden (Henk); B.N.M. Lambrecht (Bart)

    2003-01-01

    textabstractAsthma is characterized by infiltration of the airway wall with eosinophils. Although eosinophils are considered to be effector cells, recent studies have reported their ability to activate primed Th2 cells. In this study, we investigated whether eosinophils are capable

  4. 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

  5. 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...

  6. Constitutive expression of a costimulatory ligand on antigen-presenting cells in the nervous system drives demyelinating disease

    DEFF Research Database (Denmark)

    Zehntner, Simone P; Brisebois, Marcel; Tran, Elise;

    2003-01-01

    that transgenic mice constitutively expressing the costimulatory ligand B7.2/CD86 on microglia in the central nervous system (CNS) and on related cells in the proximal peripheral nervous tissue spontaneously develop autoimmune demyelinating disease. Disease-affected nervous tissue in transgenic mice showed...

  7. Granulocyte-Macrophage Colony-Stimulating Factor Expressed by Recombinant Respiratory Syncytial Virus Attenuates Viral Replication and Increases the Level of Pulmonary Antigen-Presenting Cells

    Science.gov (United States)

    Bukreyev, Alexander; Belyakov, Igor M.; Berzofsky, Jay A.; Murphy, Brian R.; Collins, Peter L.

    2001-01-01

    An obstacle to developing a vaccine against human respiratory syncytial virus (RSV) is that natural infection typically does not confer solid immunity to reinfection. To investigate methods to augment the immune response, recombinant RSV (rRSV) was constructed that expresses murine granulocyte-macrophage colony-stimulating factor (mGM-CSF) from a transcription cassette inserted into the G-F intergenic region. Replication of rRSV/mGM-CSF in the upper and lower respiratory tracts of BALB/c mice was reduced 23- to 74- and 5- to 588-fold, respectively, compared to that of the parental rRSV. Despite this strong attenuation of replication, the level of RSV-specific serum antibodies induced by rRSV/mGM-CSF was comparable to, or marginally higher than, that of the parental rRSV. The induction of RSV-specific CD8+ cytotoxic T cells was moderately reduced during the initial infection, which might be a consequence of reduced antigen expression. Mice infected with rRSV/mGM-CSF had elevated levels of pulmonary mRNA for gamma interferon (IFN-γ) and interleukin 12 (IL-12) p40 compared to animals infected by wild-type rRSV. Elevated synthesis of IFN-γ could account for the restriction of RSV replication, as was observed previously with an IFN-γ-expressing rRSV. The accumulation of total pulmonary mononuclear cells and total CD4+ T lymphocytes was accelerated in animals infected with rRSV/mGM-CSF compared to that in animals infected with the control virus, and the level of IFN-γ-positive or IL-4-positive pulmonary CD4+ cells was elevated approximately twofold. The number of pulmonary lymphoid and myeloid dendritic cells and macrophages was increased up to fourfold in mice infected with rRSV/mGM-CSF compared to those infected with the parental rRSV, and the mean expression of major histocompatibility complex class II molecules, a marker of activation, was significantly increased in the two subsets of dendritic cells. Enhanced antigen presentation likely accounts for the

  8. Cross-dressing: an alternative mechanism for antigen presentation.

    Science.gov (United States)

    Campana, Stefania; De Pasquale, Claudia; Carrega, Paolo; Ferlazzo, Guido; Bonaccorsi, Irene

    2015-12-01

    Cross-dressing involves the transfer of preformed functional peptide-MHC complexes from the surface of donor cells to recipient cells, such as dendritic cells (DCs). These cross-dressed cells might eventually present the intact, unprocessed peptide-MHC complexes to T lymphocytes. In this review we will discuss some recent findings concerning the intercellular transfer of preformed MHC complexes and the possible mechanisms by which the transfer may occur. We will report evidences showing that both MHC class I and MHC class II functional complexes might be transferred, highlighting the physiological relevance of these cross-dressed cells for the presentation of exogenous antigens to both cytotoxic and helper T lymphocytes.

  9. 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.

  10. 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

  11. Meningitis Caused by Toscana Virus Is Associated with Strong Antiviral Response in the CNS and Altered Frequency of Blood Antigen-Presenting Cells

    Directory of Open Access Journals (Sweden)

    Stefania Varani

    2015-11-01

    Full Text Available Toscana virus (TOSV is a Phlebotomus-transmitted RNA virus and a frequent cause of human meningitis and meningoencephalitis in Southern Europe during the summer season. While evidence for TOSV-related central nervous system (CNS cases is increasing, little is known about the host defenses against TOSV. We evaluated innate immune response to TOSV by analyzing frequency and activation of blood antigen-presenting cells (APCs and cytokine levels in plasma and cerebrospinal fluid (CSF from patients with TOSV neuroinvasive infection and controls. An altered frequency of different blood APC subsets was observed in TOSV-infected patients, with signs of monocytic deactivation. Nevertheless, a proper or even increased responsiveness of toll-like receptor 3 and 7/8 was observed in blood APCs of these patients as compared to healthy controls. Systemic levels of cytokines remained low in TOSV-infected patients, while levels of anti-inflammatory and antiviral mediators were significantly higher in CSF from TOSV-infected patients as compared to patients with other infectious and noninfectious neurological diseases. Thus, the early host response to TOSV appears effective for viral clearance, by proper response to TLR3 and TLR7/8 agonists in peripheral blood and by a strong and selective antiviral and anti-inflammatory response in the CNS.

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

    Science.gov (United States)

    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 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 therapeutic effect of

  13. 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

  14. 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...

  15. 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.

  16. CD80 and CD86 Costimulatory Molecules Differentially Regulate OT-II CD4+ T Lymphocyte Proliferation and Cytokine Response in Cocultures with Antigen-Presenting Cells Derived from Pregnant and Pseudopregnant Mice

    Science.gov (United States)

    Maj, Tomasz; Slawek, Anna

    2014-01-01

    Immune phenomena during the preimplantation period of pregnancy are poorly understood. The aim of our study was to assess the capacity for antigen presentation of splenic antigen-presenting cells (APCs) derived from pregnant and pseudopregnant mice in in vitro conditions. Therefore, sorted CD11c+ dendritic cells and macrophages F4/80+ and CD11b+ presenting ovalbumin (OVA) were cocultured with CD4+ T cells derived from OT-II mice's (C57BL6/J-Tg(TcraTcrb)1100Mjb/J) spleen. After 132 hours of cell culture, proliferation of lymphocytes (ELISA-BrdU), activation of these cells (flow cytometry), cytokine profile (ELISA), and influence of costimulatory molecules blocking on these parameters were measured. We did not detect any differences in regulation of Th1/Th2 cytokine balance. CD86 seems to be the main costimulatory molecule involved in the proliferation response but CD80 is the main costimulatory molecule influencing cytokine secretion in pregnant mice. In conclusion, this study showed that CD80 and CD86 costimulatory molecules regulate OT-II CD4+ T lymphocyte proliferation and cytokine response in cocultures with antigen-presenting cells derived from pregnant and pseudopregnant mice. The implications of these changes still remain unclear. PMID:24771983

  17. CD80 and CD86 Costimulatory Molecules Differentially Regulate OT-II CD4+ T Lymphocyte Proliferation and Cytokine Response in Cocultures with Antigen-Presenting Cells Derived from Pregnant and Pseudopregnant Mice

    Directory of Open Access Journals (Sweden)

    Tomasz Maj

    2014-01-01

    Full Text Available Immune phenomena during the preimplantation period of pregnancy are poorly understood. The aim of our study was to assess the capacity for antigen presentation of splenic antigen-presenting cells (APCs derived from pregnant and pseudopregnant mice in in vitro conditions. Therefore, sorted CD11c+ dendritic cells and macrophages F4/80+ and CD11b+ presenting ovalbumin (OVA were cocultured with CD4+ T cells derived from OT-II mice’s (C57BL6/J-Tg(TcraTcrb1100Mjb/J spleen. After 132 hours of cell culture, proliferation of lymphocytes (ELISA-BrdU, activation of these cells (flow cytometry, cytokine profile (ELISA, and influence of costimulatory molecules blocking on these parameters were measured. We did not detect any differences in regulation of Th1/Th2 cytokine balance. CD86 seems to be the main costimulatory molecule involved in the proliferation response but CD80 is the main costimulatory molecule influencing cytokine secretion in pregnant mice. In conclusion, this study showed that CD80 and CD86 costimulatory molecules regulate OT-II CD4+ T lymphocyte proliferation and cytokine response in cocultures with antigen-presenting cells derived from pregnant and pseudopregnant mice. The implications of these changes still remain unclear.

  18. 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

  19. 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.

  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. Skewed Helper T-Cell Responses to IL-12 Family Cytokines Produced by Antigen-Presenting Cells and the Genetic Background in Behcet’s Disease

    Directory of Open Access Journals (Sweden)

    Jun Shimizu

    2013-01-01

    Full Text Available Behcet’s disease (BD is a multisystemic inflammatory disease and is characterized by recurrent attacks on eyes, brain, skin, and gut. There is evidence that skewed T-cell responses contributed to its pathophysiology in patients with BD. Recently, we found that Th17 cells, a new helper T (Th cell subset, were increased in patients with BD, and both Th type 1 (Th1 and Th17 cell differentiation signaling pathways were overactivated. Several researches revealed that genetic polymorphisms in Th1/Th17 cell differentiation signaling pathways were associated with the onset of BD. Here, we summarize current findings on the Th cell subsets, their contribution to the pathogenesis of BD and the genetic backgrounds, especially in view of IL-12 family cytokine production and pattern recognition receptors of macrophages/monocytes.

  2. 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...

  3. Non-covalent pomegranate (Punica granatum) hydrolyzable tannin-protein complexes modulate antigen uptake, processing and presentation by a T-cell hybridoma line co-cultured with murine peritoneal macrophages.

    Science.gov (United States)

    Madrigal-Carballo, Sergio; Haas, Linda; Vestling, Martha; Krueger, Christian G; Reed, Jess D

    2016-12-01

    In this work we characterize the interaction of pomegranate hydrolyzable tannins (HT) with hen egg-white lysozyme (HEL) and determine the effects of non-covalent tannin-protein complexes on macrophage endocytosis, processing and presentation of antigen. We isolated HT from pomegranate and complex to HEL, the resulting non-covalent tannin-protein complex was characterized by gel electrophoresis and MALDI-TOF MS. Finally, cell culture studies and confocal microscopy imaging were conducted on the non-covalent pomegranate HT-HEL protein complexes to evaluate its effect on macrophage antigen uptake, processing and presentation to T-cell hybridomas. Our results indicate that non-covalent pomegranate HT-HEL protein complexes modulate uptake, processing and antigen presentation by mouse peritoneal macrophages. After 4 h of pre-incubation, only trace amounts of IL-2 were detected in the co-cultures treated with HEL alone, whereas a non-covalent pomegranate HT-HEL complex had already reached maximum IL-2 expression. Pomegranate HT may increase rate of endocytose of HEL and subsequent expression of IL-2 by the T-cell hybridomas. PMID:27406472

  4. Cross-dressing by donor dendritic cells after allogeneic bone marrow transplantation contributes to formation of the immunological synapse and maximizes responses to indirectly presented antigen.

    Science.gov (United States)

    Markey, Kate A; Koyama, Motoko; Gartlan, Kate H; Leveque, Lucie; Kuns, Rachel D; Lineburg, Katie E; Teal, Bianca E; MacDonald, Kelli P A; Hill, Geoffrey R

    2014-06-01

    The stimulation of naive donor T cells by recipient alloantigen is central to the pathogenesis of graft-versus-host disease after bone marrow transplantation (BMT). Using mouse models of transplantation, we have observed that donor cells become "cross-dressed" in very high levels of recipient hematopoietic cell-derived MHC class I and II molecules following BMT. Recipient-type MHC is transiently present on donor dendritic cells (DCs) after BMT in the setting of myeloablative conditioning but is persistent after nonmyeloablative conditioning, in which recipient hematopoietic cells remain in high numbers. Despite the high level of recipient-derived alloantigen present on the surface of donor DCs, donor T cell proliferative responses are generated only in response to processed recipient alloantigen presented via the indirect pathway and not in response to cross-dressed MHC. Assays in which exogenous peptide is added to cross-dressed MHC in the presence of naive TCR transgenic T cells specific to the MHC class II-peptide combination confirm that cross-dressed APC cannot induce T cell proliferation in isolation. Despite failure to induce T cell proliferation, cross-dressing by donor DCs contributes to generation of the immunological synapse between DCs and CD4 T cells, and this is required for maximal responses induced by classical indirectly presented alloantigen. We conclude that the process of cross-dressing by donor DCs serves as an efficient alternative pathway for the acquisition of recipient alloantigen and that once acquired, this cross-dressed MHC can assist in immune synapse formation prior to the induction of full T cell proliferative responses by concurrent indirect Ag presentation.

  5. 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.

  6. CD40-induced aggregation of MHC class II and CD80 on the cell surface leads to an early enhancement in antigen presentation.

    Science.gov (United States)

    Clatza, Abigail; Bonifaz, Laura C; Vignali, Dario A A; Moreno, José

    2003-12-15

    Ligation of CD40 on B cells increases their ability to present Ag and to activate MHC class II (MHC-II)-restricted T cells. How this occurs is not entirely clear. In this study we demonstrate that CD40 ligation on Ag-presenting B cells (APC) for a short period between 30 min and 3 h has a rapid, augmenting effect on the ability of a B cell line and normal B cells to activate T cells. This is not due to alterations in Ag processing or to an increase in surface expression of CD80, CD86, ICAM-1, or MHC-II. This effect is particularly evident with naive, resting T lymphocytes and appears to be more pronounced under limiting Ag concentrations. Shortly after CD40 ligation on a B cell line, MHC-II and CD80 progressively accumulated in cholesterol-enriched microdomains on the cell surface, which correlated with an initial enhancement in their Ag presentation ability. Moreover, CD40 ligation induced a second, late, more sustained enhancement of Ag presentation, which correlates with a significant increase in CD80 expression by APC. Thus, CD40 signaling enhances the efficiency with which APC activate T cells by at least two related, but distinct, mechanisms: an early stage characterized by aggregation of MHC-II and CD80 clusters, and a late stage in which a significant increase in CD80 expression is observed. These results raise the possibility that one important role of CD40 is to contribute to the formation of the immunological synapse on the APC side.

  7. 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...

  8. 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

  9. 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

  10. 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

  11. 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.

  12. Effects of antigen presentation of eosinophils on lung Th1/Th2 imbalance

    Institute of Scientific and Technical Information of China (English)

    XIE Zheng-fu; SHI Huan-zhong; QIN Xue-jun; KANG Lan-fu; HUANG Chun-ping; CHEN Yi-qiang

    2005-01-01

    Background Antigen-loaded eosinophils (EOSs) instilled intratracheally into mice were capable of inducing Th2-type cytokine production in the draining lymph nodes. The aim of the present study was to evaluate whether EOSs within the tracheobronchial lumen can stimulate Th2 cell expansion in the lung tissues.Methods Airway EOSs were recovered from ovalbumin-sensitized and -challenged BALB/c mice, these EOSs were then cocultured with CD4+ cells isolated from sensitized mice in the absence or presence of anti-CD80 or/and -CD86 monoclonal antibodies. Airway EOSs were instilled into the trachea of sensitized mice. At the day 3 thereafter, the lung tissues were removed and prepared into cell suspensions for culture. Cell-free culture supernatants were collected for detection of cytokines.Results Airway EOSs functioned as CD80- and CD86-dependent antigen-presenting cells to stimulate lung CD4+ lymphocytes to produce interleukin-4, interleukin-5 and interleukin-13, but not interferon-γ in in vitro assay. When instilled intratracheally in sensitized recipient mice, airway EOSs primed lung Th2 cells in vivo for interleukin-4, interleukin-5 and interleukin-13, but not interferon-γ, production during the in vitro culture that was also CD80- and CD86-dependent. Conclusion EOSs within the lumina of airways could process inhaled antigen and function in vitro and in vivo as antigen-presenting cells to promote expansion of Th2 cells in the lungs.

  13. 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...

  14. 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’

  15. 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.

  16. 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.

  17. 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

  18. 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...

  19. Activation of human antigen-presenting cells by the mycobacterial cord factor and its glycolipid adjuvant analogue trehalose-6,6’-dibehenate

    OpenAIRE

    Ostrop, Jenny

    2015-01-01

    The mycobacterial cord factor trehalose-6,6’-dimycolate (TDM) is an abundant cell wall glycolipid of Mycobacterium tuberculosis and other mycobacteria. It causes inflammation and adjuvanticity, but it is also a major virulence factor of M. tuberculosis. Its synthetic analogue trehalose-6,6’-dibehenate (TDB) has robust adjuvant activity and induces a Th1/Th17 T cell response in animal models. The TDB-containing liposomal adjuvant formulation Caf01 has entered phase I clinical studies in humans...

  20. Calcipotriol inhibits the proliferation of hyperproliferative CD29 positive keratinocytes in psoriatic epidermis in the absence of an effect on the function and number of antigen-presenting cells

    DEFF Research Database (Denmark)

    Jensen, A.M.; Llado, Minna Fyhn Lykke; Skov, L.;

    1998-01-01

    for infiltrating leucocytes (CD45+) and Langerhans cells (CD1a+). Flow cytometric analysis showed that calcipotriol did not alter the number of CD45+ cells or Langerhans cells in psoriatic skin. These results indicate that calcipotriol does not alter either the number of the function of epidermal antigen......The aim of this study was to elucidate some of the possible mechanisms of action of the vitamin D analogue calcipotriol in vivo. Calcipotriol is finding increasing use in the treatment of psoriasis, but the primary target cell in vivo has not yet been identified. We treated psoriatic patients...... and healthy volunteers with calcipotriol and placebo ointment for 4 and 7 days, and obtained epidermal cell suspensions from treated areas. Epidermal cells were cocultured with autologous T cells, isolated from peripheral blood, in the absence or the presence of a classical antigen or a superantigen. In both...

  1. Half-Antibody Functionalized Lipid-Polymer Hybrid Nanoparticles for Targeted Drug Delivery to Carcinoembryonic Antigen (CEA) Presenting Pancreatic Cancer Cells

    Science.gov (United States)

    Hu, Che-Ming Jack; Kaushal, Sharmeela; Tran Cao, Hop S.; Aryal, Santosh; Sartor, Marta; Esener, Sadik; Bouvet, Michael; Zhang, Liangfang

    2010-01-01

    Current chemotherapy regimens against pancreatic cancer are met with little success as poor tumor vascularization significantly limits the delivery of oncological drugs. High-dose targeted drug delivery, through which a drug delivery vehicle releases a large payload upon tumor localization, is thus a promising alternative strategy against this lethal disease. Herein, we synthesize anti-CEA half-antibody conjugated lipid-polymer hybrid nanoparticles and characterize their ligand conjugation yields, physicochemical properties, and targeting ability against pancreatic cancer cells. Under the same drug loading, the half-antibody targeted nanoparticles show enhanced cancer killing effect compared to the corresponding non-targeted nanoparticles. PMID:20394436

  2. Modulation of Th1/Th2 Immune Responses by Killed Propionibacterium acnes and Its Soluble Polysaccharide Fraction in a Type I Hypersensitivity Murine Model: Induction of Different Activation Status of Antigen-Presenting Cells

    Science.gov (United States)

    Mussalem, Juliana Sekeres; Ishimura, Mayari Eika; Longo-Maugéri, Ieda Maria

    2015-01-01

    Propionibacterium acnes (P. acnes) is a gram-positive anaerobic bacillus present in normal human skin microbiota, which exerts important immunomodulatory effects, when used as heat- or phenol-killed suspensions. We previously demonstrated that heat-killed P. acnes or its soluble polysaccharide (PS), extracted from the bacterium cell wall, suppressed or potentiated the Th2 response to ovalbumin (OVA) in an immediate hypersensitivity model, depending on the treatment protocol. Herein, we investigated the mechanisms responsible for these effects, using the same model and focusing on the activation status of antigen-presenting cells (APCs). We verified that higher numbers of APCs expressing costimulatory molecules and higher expression levels of these molecules are probably related to potentiation of the Th2 response to OVA induced by P. acnes or PS, while higher expression of toll-like receptors (TLRs) seems to be related to Th2 suppression. In vitro cytokines production in cocultures of dendritic cells and T lymphocytes indicated that P. acnes and PS seem to perform their effects by acting directly on APCs. Our data suggest that P. acnes and PS directly act on APCs, modulating the expression of costimulatory molecules and TLRs, and these differently activated APCs drive distinct T helper patterns to OVA in our model. PMID:25973430

  3. 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

  4. 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 ...

  5. 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.)

  6. 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...

  7. Mouse bone marrow-derived dendritic cells can phagocytize the Sporothrix schenckii, and mature and activate the immune response by secreting interleukin-12 and presenting antigens to T lymphocytes.

    Science.gov (United States)

    Kusuhara, Masahiro; Qian, Hua; Li, Xiaoguang; Tsuruta, Daisuke; Tsuchisaka, Atsunari; Ishii, Norito; Ohata, Chika; Furumura, Minao; Hashimoto, Takashi

    2014-05-01

    In sporotrichosis, dermal dendritic cells were considered to participate in induction of the immune responses against Sporothrix schenckii infection. However, it is still unclear whether and how dermal dendritic cells were involved in the progress. To clarify the pathogenic role of dermal dendritic cells (DC) in sporotrichosis, we examined the phagocytosis, maturation stages, cytokine production and antigen-presenting ability of mouse bone marrow-derived DC after stimulation with S. schenckii. By analysis of flow cytometry, electron microscope and confocal microscope, mouse bone marrow-derived DC were proved to be able to phagocytize the S. schenckii. The increased expression of CD40, CD80 and CD86 on the surface of S. schenckii-pulsed mouse bone marrow-derived DC was detected by flow cytometer, indicating that the S. schenckii-pulsed mouse bone marrow-derived DC underwent the maturation program. The secretory enhancement of interleukin (IL)-12, but not IL-4, was found in S. schenckii-pulsed mouse bone marrow-derived DC, suggesting the possible activation of T-helper 1 prone immune responses. Furthermore, S. schenckii-pulsed mouse bone marrow-derived DC were demonstrated to be capable of inducing the proliferation of T lymphocytes from BALB/c mice that were pre-sensitized with S. schenckii. Together, all the results implied that dermal DC may participate in the induction of immune responses against S. schenckii infection in sporotrichosis.

  8. Suppression of autophagy and antigen presentation by Mycobacterium tuberculosis PE_PGRS47.

    Science.gov (United States)

    Saini, Neeraj K; Baena, Andres; Ng, Tony W; Venkataswamy, Manjunatha M; Kennedy, Steven C; Kunnath-Velayudhan, Shajo; Carreño, Leandro J; Xu, Jiayong; Chan, John; Larsen, Michelle H; Jacobs, William R; Porcelli, Steven A

    2016-01-01

    Suppression of major histocompatibility complex (MHC) class II antigen presentation is believed to be among the major mechanisms used by Mycobacterium tuberculosis to escape protective host immune responses. Through a genome-wide screen for the genetic loci of M. tuberculosis that inhibit MHC class II-restricted antigen presentation by mycobacteria-infected dendritic cells, we identified the PE_PGRS47 protein as one of the responsible factors. Targeted disruption of the PE_PGRS47 (Rv2741) gene led to attenuated growth of M. tuberculosis in vitro and in vivo, and a PE_PGRS47 mutant showed enhanced MHC class II-restricted antigen presentation during in vivo infection of mice. Analysis of the effects of deletion or over-expression of PE_PGRS47 implicated this protein in the inhibition of autophagy in infected host phagocytes. Our findings identify PE_PGRS47 as a functionally relevant, non-redundant bacterial factor in the modulation of innate and adaptive immunity by M. tuberculosis, suggesting strategies for improving antigen presentation and the generation of protective immunity during vaccination or infection. PMID:27562263

  9. Suppression of autophagy and antigen presentation by Mycobacterium tuberculosis PE_PGRS47.

    Science.gov (United States)

    Saini, Neeraj K; Baena, Andres; Ng, Tony W; Venkataswamy, Manjunatha M; Kennedy, Steven C; Kunnath-Velayudhan, Shajo; Carreño, Leandro J; Xu, Jiayong; Chan, John; Larsen, Michelle H; Jacobs, William R; Porcelli, Steven A

    2016-08-15

    Suppression of major histocompatibility complex (MHC) class II antigen presentation is believed to be among the major mechanisms used by Mycobacterium tuberculosis to escape protective host immune responses. Through a genome-wide screen for the genetic loci of M. tuberculosis that inhibit MHC class II-restricted antigen presentation by mycobacteria-infected dendritic cells, we identified the PE_PGRS47 protein as one of the responsible factors. Targeted disruption of the PE_PGRS47 (Rv2741) gene led to attenuated growth of M. tuberculosis in vitro and in vivo, and a PE_PGRS47 mutant showed enhanced MHC class II-restricted antigen presentation during in vivo infection of mice. Analysis of the effects of deletion or over-expression of PE_PGRS47 implicated this protein in the inhibition of autophagy in infected host phagocytes. Our findings identify PE_PGRS47 as a functionally relevant, non-redundant bacterial factor in the modulation of innate and adaptive immunity by M. tuberculosis, suggesting strategies for improving antigen presentation and the generation of protective immunity during vaccination or infection.

  10. 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

  11. 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.

  12. 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

  13. Signal transduction by HLA class II antigens expressed on activated T cells

    DEFF Research Database (Denmark)

    Ødum, Niels; Martin, P J; Schieven, G L;

    1991-01-01

    Human T cells express HLA class II antigens upon activation. Although activated, class II+ T cells can present alloantigens under certain circumstances, the functional role of class II antigens on activated T cells remains largely unknown. Here, we report that cross-linking of HLA-DR molecules ex...

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. Toxicities of chimeric antigen receptor T cells: recognition and management.

    Science.gov (United States)

    Brudno, Jennifer N; Kochenderfer, James N

    2016-06-30

    Chimeric antigen receptor (CAR) T cells can produce durable remissions in hematologic malignancies that are not responsive to standard therapies. Yet the use of CAR T cells is limited by potentially severe toxicities. Early case reports of unexpected organ damage and deaths following CAR T-cell therapy first highlighted the possible dangers of this new treatment. CAR T cells can potentially damage normal tissues by specifically targeting a tumor-associated antigen that is also expressed on those tissues. Cytokine release syndrome (CRS), a systemic inflammatory response caused by cytokines released by infused CAR T cells can lead to widespread reversible organ dysfunction. CRS is the most common type of toxicity caused by CAR T cells. Neurologic toxicity due to CAR T cells might in some cases have a different pathophysiology than CRS and requires different management. Aggressive supportive care is necessary for all patients experiencing CAR T-cell toxicities, with early intervention for hypotension and treatment of concurrent infections being essential. Interleukin-6 receptor blockade with tocilizumab remains the mainstay pharmacologic therapy for CRS, though indications for administration vary among centers. Corticosteroids should be reserved for neurologic toxicities and CRS not responsive to tocilizumab. Pharmacologic management is complicated by the risk of immunosuppressive therapy abrogating the antimalignancy activity of the CAR T cells. This review describes the toxicities caused by CAR T cells and reviews the published approaches used to manage toxicities. We present guidelines for treating patients experiencing CRS and other adverse events following CAR T-cell therapy. PMID:27207799

  19. 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

  20. Understanding the immunogenicity and antigenicity of nanomaterials: Past, present and future.

    Science.gov (United States)

    Ilinskaya, Anna N; Dobrovolskaia, Marina A

    2016-05-15

    Nanoparticle immunogenicity and antigenicity have been under investigation for many years. During the past decade, significant progress has been made in understanding what makes a nanoparticle immunogenic, how immune cells respond to nanoparticles, what consequences of nanoparticle-specific antibody formation exist and how they challenge the application of nanoparticles for drug delivery. Moreover, it has been recognized that accidental contamination of therapeutic protein formulations with nanosized particulate materials may contribute to the immunogenicity of this type of biotechnology products. While the immunological properties of engineered nanomaterials and their application as vaccine carriers and adjuvants have been given substantial consideration in the current literature, little attention has been paid to nanoparticle immuno- and antigenicity. To fill in this gap, we herein provide an overview of this subject to highlight the current state of the field, review past and present research, and discuss future research directions.

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

    Directory of Open Access Journals (Sweden)

    Endang Winiati Bachtiar

    2015-11-01

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

  2. Isolation and characterization of NIH 3T3 cells expressing polyomavirus small T antigen

    Energy Technology Data Exchange (ETDEWEB)

    Noda, T.; Satake, M.; Robins, T.; Ito, Y.

    1986-10-01

    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 10/sup 6/ 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.

  3. 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 thyroiditis (HT), Graves' disease (GD) and healthy controls were incubated with human thyroglobulin (Tg) before adding normal peripheral blood mononuclear cells. The deposition of immunoglobulins and C3 fragments on B cells was then assessed. Inclusion of Tg in serum from HT patients promoted B cell capture...... of IgG and C3 fragments. Furthermore, the binding of Tg to B cells in preparations of normal blood cells was higher in HT serum than in serum from controls and correlated positively with the serum anti-Tg activity, as did the B and CD4+ T cell proliferation. Disruption of the three-dimensional structure...

  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. 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

    2016-01-01

    ABSTRACT 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

  6. 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

  7. Effect of multiple genetic polymorphisms on antigen presentation and susceptibility to Mycobacterium tuberculosis infection.

    Science.gov (United States)

    Chang, Stewart T; Linderman, Jennifer J; Kirschner, Denise E

    2008-07-01

    Several molecules related to antigen presentation, including gamma interferon (IFN-gamma) and the major histocompatibility complex (MHC), are encoded by polymorphic genes. Some polymorphisms were found to affect susceptibility to tuberculosis (TB) when they were considered singly in epidemiological studies, but how multiple polymorphisms interact to determine susceptibility to TB in an individual remains an open question. We hypothesized that polymorphisms in some genes may counteract or intensify the effects of polymorphisms in other genes. For example, an increase in IFN-gamma expression may counteract the weak binding that a particular MHC variant displays for a peptide from Mycobacterium tuberculosis to establish the same T-cell response as another, more strongly binding MHC variant. To test this hypothesis, we developed a mathematical model of antigen presentation based on experimental data for the known effects of genetic polymorphisms and simulated time courses when multiple polymorphisms were present. We found that polymorphisms in different genes could affect antigen presentation to the same extent and therefore compensate for each other. Furthermore, we defined the conditions under which such relationships could exist. For example, increased IFN-gamma expression compensated for decreased peptide-MHC affinity in the model only above a certain threshold of expression. Below this threshold, changes in IFN-gamma expression were ineffectual compared to changes in peptide-MHC affinity. The finding that polymorphisms exhibit such relationships could explain discrepancies in the epidemiological literature, where some polymorphisms have been inconsistently associated with susceptibility to TB. Furthermore, the model allows polymorphisms to be ranked by effect, providing a new tool for designing association studies.

  8. 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...

  9. Diminished Memory T-Cell Expansion Due to Delayed Kinetics of Antigen Expression by Lentivectors.

    Directory of Open Access Journals (Sweden)

    Karina Furmanov

    Full Text Available Memory CD8(+ T lymphocytes play a central role in protective immunity. In attempt to increase the frequencies of memory CD8(+ T cells, repeated immunizations with viral vectors are regularly explored. Lentivectors have emerged as a powerful vaccine modality with relatively low pre-existing and anti-vector immunity, thus, thought to be ideal for boosting memory T cells. Nevertheless, we found that lentivectors elicited diminished secondary T-cell responses that did not exceed those obtained by priming. This was not due to the presence of anti-vector immunity, as limited secondary responses were also observed following heterologous prime-boost immunizations. By dissecting the mechanisms involved in this process, we demonstrate that lentivectors trigger exceptionally slow kinetics of antigen expression, while optimal activation of lentivector-induced T cells relays on durable expression of the antigen. These qualities hamper secondary responses, since lentivector-encoded antigen is rapidly cleared by primary cytotoxic T cells that limit its presentation by dendritic cells. Indeed, blocking antigen clearance by cytotoxic T cells via FTY720 treatment, fully restored antigen presentation. Taken together, while low antigen expression is expected during secondary immunization with any vaccine vector, our results reveal that the intrinsic delayed expression kinetics of lentiviral-encoded antigen, further dampens secondary CD8(+ T-cell expansion.

  10. Cell wall anchoring of the Campylobacter antigens to Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Patrycja Anna Kobierecka

    2016-02-01

    Full Text Available 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 Campylobacter 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 analysed 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 LAB (Lactic Acid Bacteria 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

  11. 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.

  12. 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

  13. Enteroantigen-presenting B cells efficiently stimulate CD4(+) T cells in vitro

    DEFF Research Database (Denmark)

    Schmidt, Esben Gjerløff Wedebye; Kristensen, Nanna Ny; Claesson, Mogens Helweg;

    2011-01-01

    Presentation of enterobacterial antigens by antigen-presenting cells and activation of enteroantigen-specific CD4(+) T cells are considered crucial steps in inflammatory bowel disease (IBD) pathology. The detrimental effects of such CD4(+) T cells have been thoroughly demonstrated in models...... of colitis. Also, we have previously established an in vitro assay where murine enteroantigen-specific colitogenic CD4(+) CD25(-) T cells are activated by splenocytes pulsed with an enterobacterial extract....

  14. Immune Responses of Dendritic Cells Loaded with Antigens from Apoptotic Cholangiocarcinoma Cells Caused by γ-Irradation

    Institute of Scientific and Technical Information of China (English)

    WUGang; HANBenli; PEIXuetao

    2002-01-01

    Objective:To investigate the induction cytotoxic T cells(CTLs) with antitumor activity and therapeutic efficacy after dendritic cells(DCs) acquired antigen from apoptotic cholangiocarcinoma cells caused by γ-irradiation. Methods:DCs from peripheral blood mononuclear cells (PBMC) that maintain the antigen capturing and processing capacity charateristic of immature cells have been established in vitro, using granulocyte macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4). Then, in cholangiocarcinoma cells apoptosis was induced by γ-irradiation. The experimental groups were as follows:(1)coculture of DCs and apoptotic cancer cells and T cells;(2)coculture of DCs and necrotic cancer cells and T cells;(3)coculture of DCs, cultured cancer cell and T cells. They are cocultured for 7 days.DCs and T cells were riched, isolated and their antitumor response was tested. Results:The cells had typical dendritic morphology, expressed high levels of CDla and B7, acquired antigen from apoptotic cells caused by γ-irradiation and induced an increased T cell stimulatory capacity in mixed lymphocyte reactions (MLR). Conclusion:DCs obtained from PBMCs using GM-CSF and IL-4 can efficiently present antigen derived from apoptotic cells caused by γ-irradiation and efficiently induce T cells.This strategy, therefore, may present an effective approach to transduce DCs with antigen.

  15. Dendritic cell maturation and cross-presentation: timing matters!

    Science.gov (United States)

    Alloatti, Andrés; Kotsias, Fiorella; Magalhaes, Joao Gamelas; Amigorena, Sebastian

    2016-07-01

    As a population, dendritic cells (DCs) appear to be the best cross-presenters of internalized antigens on major histocompatibility complex class I molecules in the mouse. To do this, DCs have developed a number of unique and dedicated means to control their endocytic and phagocytic pathways: among them, the capacity to limit acidification of their phagosomes, to prevent proteolytic degradation, to delay fusion of phagosomes to lysosomes, to recruit ER proteins to phagosomes, and to export phagocytosed antigens to the cytosol. The regulation of phagocytic functions, and thereby of antigen processing and presentation by innate signaling, represents a critical level of integration of adaptive and innate immune responses. Understanding how innate signals control antigen cross-presentation is critical to define effective vaccination strategies for CD8(+) T-cell responses.

  16. NLRC5, AT THE HEART OF ANTIGEN PRESENTATION

    Directory of Open Access Journals (Sweden)

    Andreas eNeerincx

    2013-11-01

    Full Text Available Nucleotide-binding domain and leucine-rich repeat containing receptors (NLRs are intracellular proteins mainly involved in pathogen recognition, inflammatory responses, and cell death. Until recently, the function of the family member NLR caspase recruitment domain (CARD containing 5 (NLRC5 has been a matter of debate. It is now clear that NLRC5 acts as a transcriptional regulator of the major-histocompatibility complex (MHC class I. In this review we detail the development of our understanding of NLRC5 function, discussing both the accepted and the controversial aspects of NLRC5 activity. We give insight into the molecular mechanisms, and the potential implications, of NLRC5 function in health and disease.

  17. Antigen Processing by Autoreactive B Cells Promotes Determinant Spreading

    Institute of Scientific and Technical Information of China (English)

    Yang D.Dai; George Carayanniotis; Eli Sercarz

    2005-01-01

    Acute primary immune responses tend to focus on few immunodominant determinants using a very limited number of T cell clones for expansion, whereas chronic inflammatory responses generally recruit a large number of different T cell clones to attack a broader range of determinants of the invading pathogens or the inflamed tissues.In T cell-mediated organ-specific autoimmune disease, a transition from the acute to the chronic phase contributes to pathogenesis, and the broadening process is called determinant spreading. The cellular components catalyzing the spreading reaction are not identified. It has been suggested that autoreactive B cells may play a central role in diversifying autoreactive T cell responses, possibly through affecting antigen processing and presentation. The clonal identity and diversity of the B cells and antibodies seem critical in regulating T cell activity and subsequent tissue damage or repair. Here, we use two autoimmune animal models, experimental autoimmune thyroiditis (EAT)and type 1 diabetes (T1D), to discuss how autoreactive B cells or antibodies alter the processing and presentation of autoantigens to regulate specific T cell response.

  18. Delayed type hypersensitivity to allogeneic mouse epidermal cell antigens, 2

    International Nuclear Information System (INIS)

    A low dose of ultraviolet B radiation impairs the effectiveness of epidermal cell antigens. We studied the effect of ultraviolet B radiation on the delayed type hypersensitivity induced by allogeneic epidermal cell antigen. The delayed type hypersensitivity response was assayed by footpad swelling in mice. When epidermal cells were exposed to ultraviolet B radiation (660 J/m2), their ability to induce T cells of delayed type hypersensitivity activation was markedly inhibited in any combination of recipient mice and allogeneic epidermal cells. The effect of ultraviolet B radiation on epidermal cells was observed before immunization and challenge. Ultraviolet B treated epidermal cells did not induce suppressor T cells in mice. These results indicate that ultraviolet B radiation destroys the antigenicity of epidermal cells. (author)

  19. Antigen loading on dendritic cells affects the lell function in stimulating T cells.

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To study the effect of antigen loading on dendritic cells (DC). Methods: DCs collected from peripheral blood monocytes were loaded with a tumor antigen from XG-7 cell line. These DCs were then co-cultured with allogeneic T cells and were compared with those DCs without antigen exposure.

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

    Institute of Scientific and Technical Information of China (English)

    张桂梅; 黄波; 李东; 王洪涛; 冯作化

    2003-01-01

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

  1. Effective Delivery of Antigen-Encapsulin Nanoparticle Fusions to Dendritic Cells Leads to Antigen-Specific Cytotoxic T Cell Activation and Tumor Rejection.

    Science.gov (United States)

    Choi, Bongseo; Moon, Hyojin; Hong, Sung Joon; Shin, Changsik; Do, Yoonkyung; Ryu, Seongho; Kang, Sebyung

    2016-08-23

    In cancer immunotherapy, robust and efficient activation of cytotoxic CD8(+) T cell immune responses is a promising, but challenging task. Dendritic cells (DCs) are well-known professional antigen presenting cells that initiate and regulate antigen-specific cytotoxic CD8(+) T cells that kill their target cells directly as well as secrete IFN-γ, a cytokine critical in tumor rejection. Here, we employed recently established protein cage nanoparticles, encapsulin (Encap), as antigenic peptide nanocarriers by genetically incorporating the OT-1 peptide of ovalbumin (OVA) protein to the three different positions of the Encap subunit. With them, we evaluated their efficacy in activating DC-mediated antigen-specific T cell cytotoxicity and consequent melanoma tumor rejection in vivo. DCs efficiently engulfed Encap and its variants (OT-1-Encaps), which carry antigenic peptides at different positions, and properly processed them within phagosomes. Delivered OT-1 peptides were effectively presented by DCs to naïve CD8(+) T cells successfully, resulting in the proliferation of antigen-specific cytotoxic CD8(+) T cells. OT-1-Encap vaccinations in B16-OVA melanoma tumor bearing mice effectively activated OT-1 peptide specific cytotoxic CD8(+) T cells before or even after tumor generation, resulting in significant suppression of tumor growth in prophylactic as well as therapeutic treatments. A large number of cytotoxic CD8(+) T cells that actively produce both intracellular and secretory IFN-γ were observed in tumor-infiltrating lymphocytes collected from B16-OVA tumor masses originally vaccinated with OT-1-Encap-C upon tumor challenges. The approaches we describe herein may provide opportunities to develop epitope-dependent vaccination systems that stimulate and/or modulate efficient and epitope-specific cytotoxic T cell immune responses in nonpathogenic diseases.

  2. 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

  3. Control of T cell antigen reactivity via programmed TCR downregulation.

    Science.gov (United States)

    Gallegos, Alena M; Xiong, Huizhong; Leiner, Ingrid M; Sušac, Bože; Glickman, Michael S; Pamer, Eric G; van Heijst, Jeroen W J

    2016-04-01

    The T cell antigen receptor (TCR) is unique in that its affinity for ligand is unknown before encounter and can vary by orders of magnitude. How the immune system regulates individual T cells that display very different reactivity to antigen remains unclear. Here we found that activated CD4(+) T cells, at the peak of clonal expansion, persistently downregulated their TCR expression in proportion to the strength of the initial antigen recognition. This programmed response increased the threshold for cytokine production and recall proliferation in a clone-specific manner and ultimately excluded clones with the highest antigen reactivity. Thus, programmed downregulation of TCR expression represents a negative feedback mechanism for constraining T cell effector function with a suitable time delay to thereby allow pathogen control while avoiding excess inflammatory damage. PMID:26901151

  4. 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...

  5. Parallel detection of antigen-specific T cell responses by combinatorial encoding of MHC multimers

    DEFF Research Database (Denmark)

    Andersen, Rikke Sick; Kvistborg, Pia; Frøsig, Thomas Mørch;

    2012-01-01

    Fluorescently labeled multimeric complexes of peptide-MHC, the molecular entities recognized by the T cell receptor, have become essential reagents for detection of antigen-specific CD8(+) T cells by flow cytometry. Here we present a method for high-throughput parallel detection of antigen-specif......(+) immune responses during cancer and infectious disease or after immunotherapy. One panel of 28 combinatorially encoded MHC multimers can be prepared in 4 h. Staining and detection takes a further 3 h....

  6. 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.

  7. Identification of a highly antigenic linear B cell epitope within Plasmodium vivax apical membrane antigen 1 (AMA-1.

    Directory of Open Access Journals (Sweden)

    Lilian Lacerda Bueno

    Full Text Available Apical membrane antigen 1 (AMA-1 is considered to be a major candidate antigen for a malaria vaccine. Previous immunoepidemiological studies of naturally acquired immunity to Plasmodium vivax AMA-1 (PvAMA-1 have shown a higher prevalence of specific antibodies to domain II (DII of AMA-1. In the present study, we confirmed that specific antibody responses from naturally infected individuals were highly reactive to both full-length AMA-1 and DII. Also, we demonstrated a strong association between AMA-1 and DII IgG and IgG subclass responses. We analyzed the primary sequence of PvAMA-1 for B cell linear epitopes co-occurring with intrinsically unstructured/disordered regions (IURs. The B cell epitope comprising the amino acid sequence 290-307 of PvAMA-1 (SASDQPTQYEEEMTDYQK, with the highest prediction scores, was identified in domain II and further selected for chemical synthesis and immunological testing. The antigenicity of the synthetic peptide was identified by serological analysis using sera from P. vivax-infected individuals who were knowingly reactive to the PvAMA-1 ectodomain only, domain II only, or reactive to both antigens. Although the synthetic peptide was recognized by all serum samples specific to domain II, serum with reactivity only to the full-length protein presented 58.3% positivity. Moreover, IgG reactivity against PvAMA-1 and domain II after depletion of specific synthetic peptide antibodies was reduced by 18% and 33% (P = 0.0001 for both, respectively. These results suggest that the linear epitope SASDQPTQYEEEMTDYQK is highly antigenic during natural human infections and is an important antigenic region of the domain II of PvAMA-1, suggesting its possible future use in pre-clinical studies.

  8. Macrophages transfer antigens to dendritic cells by releasing exosomes containing dead-cell-associated antigens partially through a ceramide-dependent pathway to enhance CD4(+) T-cell responses.

    Science.gov (United States)

    Xu, Yingping; Liu, Yi; Yang, Chunqing; Kang, Li; Wang, Meixiang; Hu, Jingxia; He, Hao; Song, Wengang; Tang, Hua

    2016-10-01

    Defects in rapid clearance of apoptotic cells lead to an accumulation of dead cells (late apoptotic or secondary necrotic cells), which results in an aberrant immune response. However, little is known about whether and how macrophages (Mφs) cooperate with dendritic cells (DCs) in the presentation of dead-cell-associated antigens in this process. By transferring high numbers of dead cells to mimic a failure of apoptotic cell clearance in vivo, we found that Mφs and neutrophils were the predominant phagocytes in the uptake of dead cells in the spleen. Moreover, both Mφs and DCs were required for an optimal CD4(+) T-cell response triggered by dead-cell-associated antigens. Importantly, although Mφs alone had a poor capacity for antigen presentation, they could transfer phagocytosed antigens to DCs for potent antigen presentation to enhance T-cell responses. Finally, we found that exosomes released from Mφs acted as a transmitter to convey antigens to DCs partially in a ceramide-dependent manner, since treatment with the neutral sphingomyelinase inhibitor GW4869 and spiroepoxide resulted in a significant reduction of T-cell proliferation in vitro and in vivo. These findings point to a novel pathway of cross-talk between Mφs and DCs, which will be helpful to explain possible mechanisms for autoimmune diseases characterized by increased rates of apoptosis.

  9. Human antigen-specific regulatory T cells generated by T cell receptor gene transfer.

    Directory of Open Access Journals (Sweden)

    Todd M Brusko

    Full Text Available BACKGROUND: Therapies directed at augmenting regulatory T cell (Treg activities in vivo as a systemic treatment for autoimmune disorders and transplantation may be associated with significant off-target effects, including a generalized immunosuppression that may compromise beneficial immune responses to infections and cancer cells. Adoptive cellular therapies using purified expanded Tregs represents an attractive alternative to systemic treatments, with results from animal studies noting increased therapeutic potency of antigen-specific Tregs over polyclonal populations. However, current methodologies are limited in terms of the capacity to isolate and expand a sufficient quantity of endogenous antigen-specific Tregs for therapeutic intervention. Moreover, FOXP3+ Tregs fall largely within the CD4+ T cell subset and are thus routinely MHC class II-specific, whereas class I-specific Tregs may function optimally in vivo by facilitating direct tissue recognition. METHODOLOGY/PRINCIPAL FINDINGS: To overcome these limitations, we have developed a novel means for generating large numbers of antigen-specific Tregs involving lentiviral T cell receptor (TCR gene transfer into in vitro expanded polyclonal natural Treg populations. Tregs redirected with a high-avidity class I-specific TCR were capable of recognizing the melanoma antigen tyrosinase in the context of HLA-A*0201 and could be further enriched during the expansion process by antigen-specific reactivation with peptide loaded artificial antigen presenting cells. These in vitro expanded Tregs continued to express FOXP3 and functional TCRs, and maintained the capacity to suppress conventional T cell responses directed against tyrosinase, as well as bystander T cell responses. Using this methodology in a model tumor system, murine Tregs designed to express the tyrosinase TCR effectively blocked antigen-specific effector T cell (Teff activity as determined by tumor cell growth and luciferase reporter

  10. Recognition of antigen-specific B-cell receptors from chronic lymphocytic leukemia patients by synthetic antigen surrogates.

    Science.gov (United States)

    Sarkar, Mohosin; Liu, Yun; Morimoto, Jumpei; Peng, Haiyong; Aquino, Claudio; Rader, Christoph; Chiorazzi, Nicholas; Kodadek, Thomas

    2014-12-18

    In patients with chronic lymphocytic leukemia (CLL), a single neoplastic antigen-specific B cell accumulates and overgrows other B cells, leading to immune deficiency. CLL is often treated with drugs that ablate all B cells, leading to further weakening of humoral immunity, and a more focused therapeutic strategy capable of targeting only the pathogenic B cells would represent a significant advance. One approach to this would be to develop synthetic surrogates of the CLL antigens allowing differentiation of the CLL cells and healthy B cells in a patient. Here, we describe nonpeptidic molecules capable of targeting antigen-specific B cell receptors with good affinity and selectivity using a combinatorial library screen. We demonstrate that our hit compounds act as synthetic antigen surrogates and recognize CLL cells and not healthy B cells. Additionally, we argue that the technology we developed can be used to identify other classes of antigen surrogates.

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

    OpenAIRE

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

    2007-01-01

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

  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. Typing of murine cell-surface antigens by cellular radioimmunoassay

    International Nuclear Information System (INIS)

    A cellular radioimmunoassay utilizing 125I-labelled Protein A was used for detecting antigen-antibody complexes on gultaraldehyde fixed cells attached to microtiter plates. This method is rapid, sensitive and specific for revealing H-2 private and public specificities as well as Ia and Lyt antigens. As plates may be kept for months, several reactivities can be tested in one step on a large panel rendering a regular supply of animals unnecessary. (Auth.)

  14. Reassessing target antigens for adoptive T cell therapy

    Science.gov (United States)

    Hinrichs, Christian S.; Restifo, Nicholas P.

    2014-01-01

    Adoptive T cell therapy can target and kill widespread malignant cells thereby inducing durable clinical responses in melanoma and selected other malignances. However, many commonly targeted tumor antigens are also expressed by healthy tissues, and T cells do not distinguish between benign and malignant tissues if both express the target antigen. As such, autoimmune toxicity from T-cell-mediated destruction of normal tissue has limited the development and adoption of this otherwise promising type of cancer therapy. A review of the unique biology of T-cell therapy and of recent clinical experience compels a reassessment of target antigens that traditionally have been viewed from the perspective of weaker immunotherapeutic modalities. In selecting target antigens for adoptive T-cell therapy, expression by tumors and not by essential healthy tissues is of paramount importance. The risk of autoimmune adverse events can be further mitigated by generating antigen receptors using strategies that reduce the chance of cross-reactivity against epitopes in unintended targets. In general, a circumspect approach to target selection and thoughtful preclinical and clinical studies are pivotal to the ongoing advancement of these promising treatments. PMID:24142051

  15. Lipopeptides: a novel antigen repertoire presented by major histocompatibility complex class I molecules.

    Science.gov (United States)

    Morita, Daisuke; Sugita, Masahiko

    2016-10-01

    Post-translationally modified peptides, such as those containing either phosphorylated or O-glycosylated serine/threonine residues, may be presented to cytotoxic T lymphocytes (CTLs) by MHC class I molecules. Most of these modified peptides are captured in the MHC class I groove in a similar manner to that for unmodified peptides. N-Myristoylated 5-mer lipopeptides have recently been identified as a novel chemical class of MHC class I-presented antigens. The rhesus classical MHC class I allele, Mamu-B*098, was found to be capable of binding N-myristoylated lipopeptides and presenting them to CTLs. A high-resolution X-ray crystallographic analysis of the Mamu-B*098:lipopeptide complex revealed that the myristic group as well as conserved C-terminal serine residue of the lipopeptide ligand functioned as anchors, whereas the short stretch of three amino acid residues located in the middle of the lipopeptides was only exposed externally with the potential to interact directly with specific T-cell receptors. Therefore, the modes of lipopeptide-ligand interactions with MHC class I and with T-cell receptors are novel and fundamentally distinct from that for MHC class I-presented peptides. Another lipopeptide-presenting MHC class I allele has now been identified, leading us to the prediction that MHC class I molecules may be separated on a functional basis into two groups: one presenting long peptides and the other presenting short lipopeptides. Since the N-myristoylation of viral proteins is often linked to pathogenesis, CTLs capable of sensing N-myristoylation may serve to control pathogenic viruses, raising the possibility for the development of a new type of lipopeptide vaccine. PMID:27402593

  16. A single subset of dendritic cells controls the cytokine bias of natural killer T cell responses to diverse glycolipid antigens.

    Science.gov (United States)

    Arora, Pooja; Baena, Andres; Yu, Karl O A; Saini, Neeraj K; Kharkwal, Shalu S; Goldberg, Michael F; Kunnath-Velayudhan, Shajo; Carreño, Leandro J; Venkataswamy, Manjunatha M; Kim, John; Lazar-Molnar, Eszter; Lauvau, Gregoire; Chang, Young-tae; Liu, Zheng; Bittman, Robert; Al-Shamkhani, Aymen; Cox, Liam R; Jervis, Peter J; Veerapen, Natacha; Besra, Gurdyal S; Porcelli, Steven A

    2014-01-16

    Many hematopoietic cell types express CD1d and are capable of presenting glycolipid antigens to invariant natural killer T cells (iNKT cells). However, the question of which cells are the principal presenters of glycolipid antigens in vivo remains controversial, and it has been suggested that this might vary depending on the structure of a particular glycolipid antigen. Here we have shown that a single type of cell, the CD8α(+) DEC-205(+) dendritic cell, was mainly responsible for capturing and presenting a variety of different glycolipid antigens, including multiple forms of α-galactosylceramide that stimulate widely divergent cytokine responses. After glycolipid presentation, these dendritic cells rapidly altered their expression of various costimulatory and coinhibitory molecules in a manner that was dependent on the structure of the antigen. These findings show flexibility in the outcome of two-way communication between CD8α(+) dendritic cells and iNKT cells, providing a mechanism for biasing toward either proinflammatory or anti-inflammatory responses.

  17. Tracking antigen-specific T-cells during clinical tolerance induction in humans.

    Directory of Open Access Journals (Sweden)

    Aamir Aslam

    Full Text Available Allergen immunotherapy presents an opportunity to define mechanisms of induction of clinical tolerance in humans. Significant progress has been made in our understanding of changes in T cell responses during immunotherapy, but existing work has largely been based on functional T cell assays. HLA-peptide-tetrameric complexes allow the tracking of antigen-specific T-cell populations based on the presence of specific T-cell receptors and when combined with functional assays allow a closer assessment of the potential roles of T-cell anergy and clonotype evolution. We sought to develop tools to facilitate tracking of antigen-specific T-cell populations during wasp-venom immunotherapy in people with wasp-venom allergy. We first defined dominant immunogenic regions within Ves v 5, a constituent of wasp venom that is known to represent a target antigen for T-cells. We next identified HLA-DRB1*1501 restricted epitopes and used HLA class II tetrameric complexes alongside cytokine responses to Ves v 5 to track T-cell responses during immunotherapy. In contrast to previous reports, we show that there was a significant initial induction of IL-4 producing antigen-specific T-cells within the first 3-5 weeks of immunotherapy which was followed by reduction of circulating effector antigen-specific T-cells despite escalation of wasp-venom dosage. However, there was sustained induction of IL-10-producing and FOXP3 positive antigen-specific T cells. We observed that these IL-10 producing cells could share a common precursor with IL-4-producing T cells specific for the same epitope. Clinical tolerance induction in humans is associated with dynamic changes in frequencies of antigen-specific T-cells, with a marked loss of IL-4-producing T-cells and the acquisition of IL-10-producing and FOXP3-positive antigen-specific CD4+ T-cells that can derive from a common shared precursor to pre-treatment effector T-cells. The development of new approaches to track antigen

  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. 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

  20. Antigen-induced and non-antigen-induced histamine release from rat mast cells sensitized with mouse antiserum.

    Directory of Open Access Journals (Sweden)

    Kurose,Masao

    1981-10-01

    Full Text Available Marked IgE-mediated histamine release from rat mast cells sensitized in vitro with mouse antiserum occurs in the presence of added Ca++ and phosphatidylserine (PS, although a considerable degree of antigen-induced histamine release which may utilize intracellular or cell-bound calcium is also observed. The decay in the responsiveness to Ca++ of the sensitized cells stimulated by antigen in Ca++-free medium in the presence of PS is relatively slow, and maximum release is produced by Ca++ added 1 min after antigen. Histamine release also occurs when Ca++ is added after PS in the absence of antigen to the sensitized cells suspended in Ca++-free medium. Unlike the antigen-induced release, the intensity of this non-antigen-induced release varies depending on both mast-cell and antiserum pools. A heat-labile factor(s, which is different from antigen-specific IgE antibody and is also contained in normal mouse serum, is involved in this reaction. In the antigen-nondependent (PS + Ca++-induced release, no decay in the responsiveness to Ca++ is observed after PS addition. Both the antigen-induced and non-antigen-induced release are completed fairly rapidly and are dependent of temperature, pH and energy.

  1. Reactivity of Monoclonal Antibodies Directed against Lung Cancer Antigens with Human Lung, Breast and Colon Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Udo Schumacher

    1993-01-01

    Full Text Available A panel of monoclonal antibodies (n=72 including controls directed against lung cancer antigens was screened immunohistochemically against a panel of seven human lung cancer cell lines (including small cell carcinoma, squamous cell carcinoma, adenocarcinoma and mesothelioma, six human breast cancer cell lines and one human colon cancer cell line, The majority of the antibodies (n=42 reacted also with antigens present on breast and colon cancer cell lines, This cross reactivity especially between lung and breast cancer cell lines is not altogether unexpected since antigens common to breast and lung tissue including their neoplasms such as MUC1 antigen have been described, Our results indicate that epitopes shared by lung and breast cancers are probably more common than previously thought. The relevance for prognosis and therapy of these shared antigens, especially as disease markers in breast cancer, has to be investigated.

  2. Langerhans Cell Histiocytosis Presenting as Uncontrolled Asthma

    Directory of Open Access Journals (Sweden)

    Frederic A. Rawlins

    2013-01-01

    Full Text Available 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 cor pulmonale may be observed in advanced disease. The chest radiograph is typically abnormal with nodular or interstitial infiltrates and cystic changes. High-resolution computed tomography of the chest with these findings in the middle and upper lobes of an adult smoker is virtually diagnostic of LCH. Pulmonary function assessment is variable. Asthma has rarely been reported in association with this disorder. There are only three reported cases of the diagnosis of concomitant asthma which have been made in association with the diagnosis of LCH. We present a case in which our patient presented with signs and symptoms of asthma to include confirmatory findings of airway hyperresponsiveness. The diagnosis of LCH was established after the patient failed to respond to conventional treatment for asthma, and further evaluation was completed.

  3. 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...

  4. 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.

  5. Efficient induction of CD25- iTreg by co-immunization requires strongly antigenic epitopes for T cells

    Directory of Open Access Journals (Sweden)

    Li Jinyao

    2011-05-01

    Full Text Available Abstract Background We previously showed that co-immunization with a protein antigen and a DNA vaccine coding for the same antigen induces CD40low IL-10high tolerogenic DCs, which in turn stimulates the expansion of antigen-specific CD4+CD25-Foxp3+ regulatory T cells (CD25- iTreg. However, it was unclear how to choose the antigen sequence to maximize tolerogenic antigen presentation and, consequently, CD25- iTreg induction. Results In the present study, we demonstrated the requirement of highly antigenic epitopes for CD25- iTreg induction. Firstly, we showed that the induction of CD25- iTreg by tolerogenic DC can be blocked by anti-MHC-II antibody. Next, both the number and the suppressive activity of CD25- iTreg correlated positively with the overt antigenicity of an epitope to activate T cells. Finally, in a mouse model of dermatitis, highly antigenic epitopes derived from a flea allergen not only induced more CD25- iTreg, but also more effectively prevented allergenic reaction to the allergen than did weakly antigenic epitopes. Conclusions Our data thus indicate that efficient induction of CD25- iTreg requires highly antigenic peptide epitopes. This finding suggests that highly antigenic epitopes should be used for efficient induction of CD25- iTreg for clinical applications such as flea allergic dermatitis.

  6. Strategy for eliciting antigen-specific CD8+ T cell-mediated immune response against a cryptic CTL epitope of merkel cell polyomavirus large T antigen

    Directory of Open Access Journals (Sweden)

    Gomez Bianca P

    2012-10-01

    Full Text Available Abstract Background Merkel cell carcinoma (MCC is a relatively new addition to the expanding category of oncovirus-induced cancers. Although still comparably rare, the number of cases has risen dramatically in recent years. Further complicating this trend is that MCC is an extremely aggressive neoplasm with poor patient prognosis and limited treatment options for advanced disease. The causative agent of MCC has been identified as the merkel cell polyomavirus (MCPyV. The MCPyV-encoded large T (LT antigen is an oncoprotein that is theorized to be essential for virus-mediated tumorigenesis and is therefore, an excellent MCC antigen for the generation of antitumor immune responses. As a foreign antigen, the LT oncoprotein avoids the obstacle of immune tolerance, which normally impedes the development of antitumor immunity. Ergo, it is an excellent target for anti-MCC immunotherapy. Since tumor-specific CD8+ T cells lead to better prognosis for MCC and numerous other cancers, we have generated a DNA vaccine that is capable of eliciting LT-specific CD8+ T cells. The DNA vaccine (pcDNA3-CRT/LT encodes the LT antigen linked to a damage-associated molecular pattern, calreticulin (CRT, as it has been demonstrated that the linkage of CRT to antigens promotes the induction of antigen-specific CD8+ T cells. Results The present study shows that DNA vaccine-induced generation of LT-specific CD8+ T cells is augmented by linking CRT to the LT antigen. This is relevant since the therapeutic effects of the pcDNA3-CRT/LT DNA vaccine is mediated by LT-specific CD8+ T cells. Mice vaccinated with the DNA vaccine produced demonstrably more LT-specific CD8+ T cells. The DNA vaccine was also able to confer LT-specific CD8+ T cell-mediated protective and therapeutic effects to prolong the survival of mice with LT-expressing tumors. In the interest of determining the LT epitope which most MCC-specific CD8+ T cells recognize, we identified the amino acid sequence of the

  7. Antigenicity and immunogenicity of an extract from the cell wall and cell membrane of Histoplasma capsulatum yeast cells.

    OpenAIRE

    Gómez, A M; Rhodes, J C; Deepe, G S

    1991-01-01

    In order to identify T-cell antigens from Histoplasma capsulatum yeast cells, we prepared a detergent extract of the cell wall and cell membrane of yeast-phase H. capsulatum G217B and analyzed its antigenicity and immunogenicity. Mice injected with viable H. capsulatum yeast cells or with 500 or 1,000 micrograms of the extract mounted a delayed-type hypersensitivity response to solubilized cell wall and cell membrane. Vaccination with this antigenic preparation conferred a protective immune r...

  8. Normal adult ramified microglia separated from other central nervous system macrophages by flow cytometric sorting: Phenotypic differences defined and direct ex vivo antigen presentation to myelin basic protein-reactive CD4{sup +} T cells compared

    Energy Technology Data Exchange (ETDEWEB)

    Ford, A.L.; Goodsall, A.L.; Sedgwick, J.D. [Centenary Institute of Cancer Medicine and Cell Biology, Sydney (Australia)] [and others

    1995-05-01

    Ramified microglia in the adult central nervous system (CNS) are the principal glial element up-regulating MHC class I and II expression in response to inflammatory events or neuronal damage. A proportion of these cells also express MHC class II constitutively in the normal CNS. The role of microglia as APCs for CD4{sup +} cells extravasating into the CNS remains undefined. In this study, using irradiation bone marrow chimeras in CD45-congenic rats, the phenotype CD45{sup low}CD11b/c{sup +} is shown to identify microglial cells specifically within the CNS. Highly purified populations of microglia and nonmicroglial but CNS-associated macrophages (CD45{sup high}CD11b/c{sup +}) have been obtained directly from the adult CNS, by using flow cytometric sorting. Morphologically, freshly isolated microglia vs other CNS macrophages are quite distinct. Of the two populations recovered from the normal CNS, it is the minority CD45{sup high}CD11 b/c{sup +} transitional macrophage population, and not microglia, that is the effective APC for experimental autoimmune encephalomyelitis-inducing CD4{sup +} myelin basic protein (MBP)-reactive T cells. CD45{sup high}CD11b/c{sup +} CNS macrophages also stimulate MBP-reactive T cells without addition of MBP to culture suggesting presentation of endogenous Ag. This is the first study in which microglia vs other CNS macrophages have been analyzed for APC ability directly from the CNS, with substantial cross-contamination between the two populations eliminated. The heterogeneity of these populations in terms of APC function is clearly demonstrated. Evidence is still lacking that adult CNS microglia have the capacity to interact with and stimulate CD4{sup +} T cells to proliferate or secrete IL-2. 60 refs., 6 figs., 1 tab.

  9. Development of antibodies to human embryonic stem cell antigens

    OpenAIRE

    Stanley Marisa; Rao Mahendra S; Olson Judith M; Cai Jingli; Taylor Eva; Ni Hsiao-Tzu

    2005-01-01

    Abstract Background Using antibodies to specific protein antigens is the method of choice to assign and identify cell lineage through simultaneous analysis of surface molecules and intracellular markers. Embryonic stem cell research can be benefited from using antibodies specific to transcriptional factors/markers that contribute to the "stemness" phenotype or critical for cell lineage. Results In this report, we have developed and validated antibodies (either monoclonal or polyclonal) specif...

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

    Science.gov (United States)

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

    2004-03-15

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

  11. Engineering antigen-specific T cells from genetically modified human hematopoietic stem cells in immunodeficient mice.

    Directory of Open Access Journals (Sweden)

    Scott G Kitchen

    Full Text Available There is a desperate need for effective therapies to fight chronic viral infections. The immune response is normally fastidious at controlling the majority of viral infections and a therapeutic strategy aimed at reestablishing immune control represents a potentially powerful approach towards treating persistent viral infections. We examined the potential of genetically programming human hematopoietic stem cells to generate mature CD8+ cytotoxic T lymphocytes that express a molecularly cloned, "transgenic" human anti-HIV T cell receptor (TCR. Anti-HIV TCR transduction of human hematopoietic stem cells directed the maturation of a large population of polyfunctional, HIV-specific CD8+ cells capable of recognizing and killing viral antigen-presenting cells. Thus, through this proof-of-concept we propose that genetic engineering of human hematopoietic stem cells will allow the tailoring of effector T cell responses to fight HIV infection or other diseases that are characterized by the loss of immune control.

  12. 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...

  13. Antigen-Specific Th17 Cells Are Primed by Distinct and Complementary Dendritic Cell Subsets in Oropharyngeal Candidiasis.

    Directory of Open Access Journals (Sweden)

    Kerstin Trautwein-Weidner

    2015-10-01

    Full Text Available Candida spp. can cause severe and chronic mucocutaneous and systemic infections in immunocompromised individuals. Protection from mucocutaneous candidiasis depends on T helper cells, in particular those secreting IL-17. The events regulating T cell activation and differentiation toward effector fates in response to fungal invasion in different tissues are poorly understood. Here we generated a Candida-specific TCR transgenic mouse reactive to a novel endogenous antigen that is conserved in multiple distant species of Candida, including the clinically highly relevant C. albicans and C. glabrata. Using TCR transgenic T cells in combination with an experimental model of oropharyngeal candidiasis (OPC we investigated antigen presentation and Th17 priming by different subsets of dendritic cells (DCs present in the infected oral mucosa. Candida-derived endogenous antigen accesses the draining lymph nodes and is directly presented by migratory DCs. Tissue-resident Flt3L-dependent DCs and CCR2-dependent monocyte-derived DCs collaborate in antigen presentation and T cell priming during OPC. In contrast, Langerhans cells, which are also present in the oral mucosa and have been shown to prime Th17 cells in the skin, are not required for induction of the Candida-specific T cell response upon oral challenge. This highlights the functional compartmentalization of specific DC subsets in different tissues. These data provide important new insights to our understanding of tissue-specific antifungal immunity.

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

    Science.gov (United States)

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

    2004-01-01

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

  15. Molecular structure and biological function of proliferating cell nuclear antigen

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote.As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

  16. Hepatitis B virus antigens impair NK cell function.

    Science.gov (United States)

    Yang, Yinli; Han, Qiuju; Zhang, Cai; Xiao, Min; Zhang, Jian

    2016-09-01

    An inadequate immune response of the host is thought to be a critical factor causing chronic hepatitis B virus (CHB) infection. Natural killer (NK) cells, as one of the key players in the eradication and control of viral infections, were functionally impaired in CHB patients, which might contribute to viral persistence. Here, we reported that HBV antigens HBsAg and HBeAg directly inhibited NK cell function. HBsAg and/or HBeAg blocked NK cell activation, cytokine production and cytotoxic granule release in human NK cell-line NK-92 cells, which might be related to the downregulation of activating receptors and upregulation of inhibitory receptor. Furthermore, the underlying mechanisms likely involved the suppression of STAT1, NF-κB and p38 MAPK pathways. These findings implicated that HBV antigen-mediated inhibition of NK cells might be an efficient strategy for HBV evasion, targeting the early antiviral responses mediated by NK cells and resulting in the establishment of chronic virus infection. Therefore, this study revealed the relationship between viral antigens and human immune function, especially a potential important interaction between HBV and innate immune responses. PMID:27341035

  17. 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

  18. Adsorption of multimeric T cell antigens on carbon nanotubes

    DEFF Research Database (Denmark)

    Fadel, Tarek R; Li, Nan; Shah, Smith;

    2013-01-01

    Antigen-specific activation of cytotoxic T cells can be enhanced up to three-fold more than soluble controls when using functionalized bundled carbon nanotube substrates ((b) CNTs). To overcome the denaturing effects of direct adsorption on (b) CNTs, a simple but robust method is demonstrated...... to stabilize the T cell stimulus on carbon nanotube substrates through non-covalent attachment of the linker neutravidin....

  19. Limited transplantation of antigen-expressing hematopoietic stem cells induces long-lasting cytotoxic T cell responses.

    Directory of Open Access Journals (Sweden)

    Warren L Denning

    Full Text Available Harnessing the ability of cytotoxic T lymphocytes (CTLs to recognize and eradicate tumor or pathogen-infected cells is a critical goal of modern immune-based therapies. Although multiple immunization strategies efficiently induce high levels of antigen-specific CTLs, the initial increase is typically followed by a rapid contraction phase resulting in a sharp decline in the frequency of functional CTLs. We describe a novel approach to immunotherapy based on a transplantation of low numbers of antigen-expressing hematopoietic stem cells (HSCs following nonmyeloablative or partially myeloablative conditioning. Continuous antigen presentation by a limited number of differentiated transgenic hematopoietic cells results in an induction and prolonged maintenance of fully functional effector T cell responses in a mouse model. Recipient animals display high levels of antigen-specific CTLs four months following transplantation in contrast to dendritic cell-immunized animals in which the response typically declines at 4-6 weeks post-immunization. Majority of HSC-induced antigen-specific CD8+ T cells display central memory phenotype, efficiently kill target cells in vivo, and protect recipients against tumor growth in a preventive setting. Furthermore, we confirm previously published observation that high level engraftment of antigen-expressing HSCs following myeloablative conditioning results in tolerance and an absence of specific cytotoxic activity in vivo. In conclusion, the data presented here supports potential application of immunization by limited transplantation of antigen-expressing HSCs for the prevention and treatment of cancer and therapeutic immunization of chronic infectious diseases such as HIV-1/AIDS.

  20. Dissection of T-cell antigen specificity in human melanoma

    DEFF Research Database (Denmark)

    Andersen, Rikke Sick; Albæk Thrue, Charlotte; Junker, Niels;

    2012-01-01

    Tumor-infiltrating lymphocytes (TIL) isolated from melanoma patients and expanded in vitro by interleukin (IL)-2 treatment can elicit therapeutic response after adoptive transfer, but the antigen specificities of the T cells transferred have not been determined. By compiling all known melanoma-as...... from different fragments of resected melanoma lesions. In summary, our findings provide an initial definition of T-cell populations contributing to tumor recognition in TILs although the specificity of many tumor-reactive TILs remains undefined.......Tumor-infiltrating lymphocytes (TIL) isolated from melanoma patients and expanded in vitro by interleukin (IL)-2 treatment can elicit therapeutic response after adoptive transfer, but the antigen specificities of the T cells transferred have not been determined. By compiling all known melanoma......-associated antigens and applying a novel technology for high-throughput analysis of T-cell responses, we dissected the composition of melanoma-restricted T-cell responses in 63 TIL cultures. T-cell reactivity screens against 175 melanoma-associated epitopes detected 90 responses against 18 different epitopes...

  1. Whole tumor antigen vaccination using dendritic cells: Comparison of RNA electroporation and pulsing with UV-irradiated tumor cells

    Directory of Open Access Journals (Sweden)

    Benencia Fabian

    2008-04-01

    Full Text Available Abstract Because of the lack of full characterization of tumor associated antigens for solid tumors, whole antigen use is a convenient approach to tumor vaccination. Tumor RNA and apoptotic tumor cells have been used as a source of whole tumor antigen to prepare dendritic cell (DC based tumor vaccines, but their efficacy has not been directly compared. Here we compare directly RNA electroporation and pulsing of DCs with whole tumor cells killed by ultraviolet (UV B radiation using a convenient tumor model expressing human papilloma virus (HPV E6 and E7 oncogenes. Although both approaches led to DCs presenting tumor antigen, electroporation with tumor cell total RNA induced a significantly higher frequency of tumor-reactive IFN-gamma secreting T cells, and E7-specific CD8+ lymphocytes compared to pulsing with UV-irradiated tumor cells. DCs electroporated with tumor cell RNA induced a larger tumor infiltration by T cells and produced a significantly stronger delay in tumor growth compared to DCs pulsed with UV-irradiated tumor cells. We conclude that electroporation with whole tumor cell RNA and pulsing with UV-irradiated tumor cells are both effective in eliciting antitumor immune response, but RNA electroporation results in more potent tumor vaccination under the examined experimental conditions.

  2. Analysis of expression profiles of MAGE-A antigens in oral squamous cell carcinoma cell lines

    Directory of Open Access Journals (Sweden)

    Reichert Torsten E

    2009-04-01

    Full Text Available Abstract Background The immunological response to solid tumours is insufficient. Therefore, tumour specific antigens have been explored to facilitate the activation of the immune system. The cancer/testis antigen class of MAGE-A antigens is a possible target for vaccination. Their differential expression profiles also modulate the course of the cancer disease and its response to antineoplastic drugs. Methods The expression profiles of MAGE-A2, -A3, -A4, -A6 and -A10 in five own oral squamous cell carcinoma cell lines were characterised by rt-PCR, qrt-PCR and immunocytochemistry with a global MAGE-A antibody (57B and compared with those of an adult keratinocyte cell line (NHEK. Results All tumour cell lines expressed MAGE-A antigens. The antigens were expressed in groups with different preferences. The predominant antigens expressed were MAGE-A2, -A3 and -A6. MAGE-A10 was not expressed in the cell lines tested. The MAGE-A gene products detected in the adult keratinocyte cell line NHEK were used as a reference. Conclusion MAGE-A antigens are expressed in oral squamous cell carcinomas. The expression profiles measured facilitate distinct examinations in forthcoming studies on responses to antineoplastic drugs or radiation therapy. MAGE-A antigens are still an interesting aim for immunotherapy.

  3. Structural characteristics of an antigen required for its interaction with Ia and recognition by T cells

    DEFF Research Database (Denmark)

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

    1987-01-01

    A detailed analysis of the residues within an immunogenic peptide that endow it with the capacity to interact with Ia and to be recognized by T cells is presented. Ia interacts with only a few of the peptide residues and overall exhibits a very broad specificity. Some residues appear to interact...... both with Ia and with T cells, leading to a model in which a peptide antigen is 'sandwiched' between Ia and the T-cell receptor....

  4. Nuclear localization of Merkel cell polyomavirus large T antigen in Merkel cell carcinoma

    International Nuclear Information System (INIS)

    To clarify whether mutations in the large T gene encoded by Merkel cell polyomavirus affect the expression and function of large T antigen in Merkel cell carcinoma cases, we investigated the expression of large T antigen in vitro and in vivo. Immunohistochemistry using a rabbit polyclonal antibody revealed that large T antigen was expressed in the nuclei of Merkel cell carcinoma cells with Merkel cell polyomavirus infection. Deletion mutant analyses identified an Arg-Lys-Arg-Lys sequence (amino acids 277-280) as a nuclear localization signal in large T antigen. Sequence analyses revealed that there were no mutations in the nuclear localization signal in any of the eleven Merkel cell polyomavirus strains examined. Furthermore, stop codons were not observed in the upstream of the nuclear localization signal in any of the Merkel cell carcinoma cases examined. These data suggest that the nuclear localization signal is highly conserved and functional in Merkel cell carcinoma cases.

  5. Comparison of antigen-specific T-cell responses of tuberculosis patients using complex or single antigens of Mycobacterium tuberculosis

    DEFF Research Database (Denmark)

    Mustafa, A S; Amoudy, H A; Wiker, H G;

    1998-01-01

    We have screened peripheral blood mononuclear cells (PBMC) from tuberculosis (TB) patients for proliferative reactivity and interferon-gamma (IFN-gamma) secretion against a panel of purified recombinant (r) and natural (n) culture filtrate (rESAT-6, nMPT59, nMPT64 and nMPB70) and somatic-derived (r....... tuberculosis, MT-CF and M. bovis BCG. We also observed that most of the high responders to complex antigens recognized all of the antigens tested (covariation), demonstrating that the repertoire of human T-cell specificities induced by natural infection is directed towards several unrelated culture filtrate...... as well as somatic-derived protein antigens. In conclusion, the results obtained suggest that the cellular immune response in humans is directed against several important target antigens of M. tuberculosis and that some antigens, such as ESAT-6, are recognized by a high number of individuals...

  6. Chimeric Antigen Receptor T Cell Therapy in Hematology.

    Science.gov (United States)

    Ataca, Pınar; Arslan, Önder

    2015-12-01

    It is well demonstrated that the immune system can control and eliminate cancer cells. Immune-mediated elimination of tumor cells has been discovered and is the basis of both cancer vaccines and cellular therapies including hematopoietic stem cell transplantation. Adoptive T cell transfer has been improved to be more specific and potent and to cause less off-target toxicity. Currently, there are two forms of engineered T cells being tested in clinical trials: T cell receptor (TCR) and chimeric antigen receptor (CAR) modified T cells. On 1 July 2014, the United States Food and Drug Administration granted 'breakthrough therapy' designation to anti-CD19 CAR T cell therapy. Many studies were conducted to evaluate the benefits of this exciting and potent new treatment modality. This review summarizes the history of adoptive immunotherapy, adoptive immunotherapy using CARs, the CAR manufacturing process, preclinical and clinical studies, and the effectiveness and drawbacks of this strategy.

  7. Antibodies to new beta cell antigen ICA12 in Latvian diabetes patients.

    Science.gov (United States)

    Shtauvere-Brameus, A; Hagopian, W; Rumba, I; Sanjeevi, C B

    2002-04-01

    In Latvia diabetes mellitus is diagnosed using the WHO's clinical criteria, and assays for the detection of autoantibodies are not available. In consequence, slowly progressive autoimmune diabetes or LADA is likely to be missed. Antibodies to GAD65 and IA-2 are the major immunological markers in autoimmune diabetes. Recently, a new beta cell antigen, called ICA12, has been identified, which has a homology to the SOX family of transcription factors. The aim of the study was to analyze the prevalence of ICA12 antibodies in diabetes mellitus patients and controls from Latvia and to see whether this antigen is important in revealing autoimmunity when antibodies against major antigens are not present. We studied 88 IDDM patients and 100 NIDDM patients as well as controls for the prevalence of GAD65, IA-2, and ICA12 antibodies by radioligand binding assay (RIA) using (35)S-labeled islet antigens. We found ICA12Abs in 26 of 88 IDDM patients (30%) vs. 4% in healthy controls (4/100) and in 9 of 100 NIDDM patients (9%) vs. 2% controls (2/100). ICA12Abs alone are present in only 3% (3/88) of the patients with IDDM and 1% (1/100) of the NIDDM patients. We conclude that ICA12 represents the minor antigens in autoimmune diabetes and that, as a minor antigen, ICA12 alone does not contribute significantly in revealing new cases of autoimmunity.

  8. Viral Escape Mutant Epitope Maintains TCR Affinity for Antigen yet Curtails CD8 T Cell Responses.

    Directory of Open Access Journals (Sweden)

    Shayla K Shorter

    Full Text Available T cells have the remarkable ability to recognize antigen with great specificity and in turn mount an appropriate and robust immune response. Critical to this process is the initial T cell antigen recognition and subsequent signal transduction events. This antigen recognition can be modulated at the site of TCR interaction with peptide:major histocompatibility (pMHC or peptide interaction with the MHC molecule. Both events could have a range of effects on T cell fate. Though responses to antigens that bind sub-optimally to TCR, known as altered peptide ligands (APL, have been studied extensively, the impact of disrupting antigen binding to MHC has been highlighted to a lesser extent and is usually considered to result in complete loss of epitope recognition. Here we present a model of viral evasion from CD8 T cell immuno-surveillance by a lymphocytic choriomeningitis virus (LCMV escape mutant with an epitope for which TCR affinity for pMHC remains high but where the antigenic peptide binds sub optimally to MHC. Despite high TCR affinity for variant epitope, levels of interferon regulatory factor-4 (IRF4 are not sustained in response to the variant indicating differences in perceived TCR signal strength. The CD8+ T cell response to the variant epitope is characterized by early proliferation and up-regulation of activation markers. Interestingly, this response is not maintained and is characterized by a lack in IL-2 and IFNγ production, increased apoptosis and an abrogated glycolytic response. We show that disrupting the stability of peptide in MHC can effectively disrupt TCR signal strength despite unchanged affinity for TCR and can significantly impact the CD8+ T cell response to a viral escape mutant.

  9. 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

  10. Germinal center B cells recognize antigen through a specialized immune synapse architecture.

    Science.gov (United States)

    Nowosad, Carla R; Spillane, Katelyn M; Tolar, Pavel

    2016-07-01

    B cell activation is regulated by B cell antigen receptor (BCR) signaling and antigen internalization in immune synapses. Using large-scale imaging across B cell subsets, we found that, in contrast with naive and memory B cells, which gathered antigen toward the synapse center before internalization, germinal center (GC) B cells extracted antigen by a distinct pathway using small peripheral clusters. Both naive and GC B cell synapses required proximal BCR signaling, but GC cells signaled less through the protein kinase C-β-NF-κB pathway and produced stronger tugging forces on the BCR, thereby more stringently regulating antigen binding. Consequently, GC B cells extracted antigen with better affinity discrimination than naive B cells, suggesting that specialized biomechanical patterns in B cell synapses regulate T cell-dependent selection of high-affinity B cells in GCs. PMID:27183103

  11. Interferon-gamma-like molecule induces Ia antigens on cultured mast cell progenitors.

    OpenAIRE

    Wong, G H; Clark-lewis, I.; McKimm-Breschkin, J L; Schrader, J W

    1982-01-01

    Persisting (P) cells (murine cells that resemble mast cells and grow continuously in vitro for prolonged periods in the presence of a specific growth factor) did not express detectable levels of Ia antigens (murine class II major histocompatibility antigens) when their growth was supported by partially purified P cell-stimulating factor. However, when these Ia-negative P cells were transferred to medium conditioned by concanavalin A-stimulated spleen cells, Ia antigens appeared within 24 hr. ...

  12. Studies of the antigenicity and immunogenicity of bromelain-pretreated red blood cells.

    Science.gov (United States)

    Cox, K O; Baddams, H; Evans, A

    1977-02-01

    The effects of the proteolytic enzyme bromelain (Br) on the antigenicity and immunogenicity of sheep and mouse red blood cells (RBC) have been investigated. The results presented support the previous claim that there are antigens present on Br RBC that are not present in an exposed form on untreated RBC and that Br RBC have lost some of the antigens present on the surface of normal RBC. The susceptibility of Br RBC to osmotic lysis was very similar to that of normal RBC, implying that the modified RBC were not more fragile than normal RBC. Injection of mice with Br mouse-RBC did not increase the unusually high "background" number of cells producing IgM antibodies against Br mouse-RBC and mice did not mount delayed-type hypersensitivity reactions against Br mouse-RBC, either before or after sensitizing injections of Br mouse-RBC. However, mouse-RBC and Br mouse-RBC elicited similar antibody responses in rabbits and guinea pigs. Although mice appeared unresponsive to Br mouse-RBC injections, delayed-type hypersensitivity responses and antibody production in primary and secondary responses were of similar levels irrespective of whether sheep-RBC or Br sheep-RBC were used as immunogens. From these studies it appears that mice have B-cells producing antibodies against the "new" antigens on Br mouse-RBC, but there are no T-cells that respond to these antigens by way of "helper" activity in antibody production or by way of cell-mediated immune reactions.

  13. Intravacuolar Membranes Regulate CD8 T Cell Recognition of Membrane-Bound Toxoplasma gondii Protective Antigen.

    Science.gov (United States)

    Lopez, Jodie; Bittame, Amina; Massera, Céline; Vasseur, Virginie; Effantin, Grégory; Valat, Anne; Buaillon, Célia; Allart, Sophie; Fox, Barbara A; Rommereim, Leah M; Bzik, David J; Schoehn, Guy; Weissenhorn, Winfried; Dubremetz, Jean-François; Gagnon, Jean; Mercier, Corinne; Cesbron-Delauw, Marie-France; Blanchard, Nicolas

    2015-12-15

    Apicomplexa parasites such as Toxoplasma gondii target effectors to and across the boundary of their parasitophorous vacuole (PV), resulting in host cell subversion and potential presentation by MHC class I molecules for CD8 T cell recognition. The host-parasite interface comprises the PV limiting membrane and a highly curved, membranous intravacuolar network (IVN) of uncertain function. Here, using a cell-free minimal system, we dissect how membrane tubules are shaped by the parasite effectors GRA2 and GRA6. We show that membrane association regulates access of the GRA6 protective antigen to the MHC I pathway in infected cells. Although insertion of GRA6 in the PV membrane is key for immunogenicity, association of GRA6 with the IVN limits presentation and curtails GRA6-specific CD8 responses in mice. Thus, membrane deformations of the PV regulate access of antigens to the MHC class I pathway, and the IVN may play a role in immune modulation. PMID:26628378

  14. Comparison of antigen-specific T-cell responses of tuberculosis patients using complex or single antigens of Mycobacterium tuberculosis

    DEFF Research Database (Denmark)

    Mustafa, A S; Amoudy, H A; Wiker, H G;

    1998-01-01

    We have screened peripheral blood mononuclear cells (PBMC) from tuberculosis (TB) patients for proliferative reactivity and interferon-gamma (IFN-gamma) secretion against a panel of purified recombinant (r) and natural (n) culture filtrate (rESAT-6, nMPT59, nMPT64 and nMPB70) and somatic-derived (r......GroES, rPstS, rGroEL and rDnaK) antigens of Mycobacterium tuberculosis. The responses of PBMC to these defined antigens were compared with the corresponding results obtained with complex antigens, such as whole-cell M. tuberculosis, M. tuberculosis culture filtrate (MT-CF) and cell wall antigens, as well...... as the vaccine strain, Mycobacterium bovis bacillus Calmette-Guerin (BCG). In addition, M. tuberculosis and MT-CF-induced T-cell lines were tested in the same assays against the panel of purified and complex antigens. The compiled data from PBMC and T-cell lines tested for antigen-induced proliferation and IFN...

  15. 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

  16. Circadian control of antigen-specific T cell responses

    Directory of Open Access Journals (Sweden)

    Nobis CC

    2016-09-01

    Full Text Available Chloé C Nobis,1–3 Nathalie Labrecque,2–4 Nicolas Cermakian1,5–8 1Douglas Mental Health University Institute, 2Maisonneuve-Rosemont Hospital Research Centre, 3Department of Microbiology, Infectious Diseases and Immunology, 4Department of Medicine, University of Montreal, 5Department of Psychiatry, 6Department of Microbiology and Immunology, 7Department of Neurology and Neurosurgery, 8Department of Physiology, McGill University, Montreal, QC, Canada Abstract: The immune system is composed of two arms, the innate and the adaptive immunity. While the innate response constitutes the first line of defense and is not specific for a particular pathogen, the adaptive response is highly specific and allows for long-term memory of the pathogen encounter. T lymphocytes (or T cells are central players in the adaptive immune response. Various aspects of T cell functions vary according to the time of day. Circadian clocks located in most tissues and cell types generate 24-hour rhythms of various physiological processes. These clocks are based on a set of clock genes, and this timing mechanism controls rhythmically the expression of numerous other genes. Clock genes are expressed in cells of the immune system, including T cells. In this review, we provide an overview of the circadian control of the adaptive immune response, with emphasis on T cells, including their development, trafficking, response to antigen, and effector functions. Keywords: circadian clock, adaptive immune response, T lymphocyte, antigen, cytokine, proliferation

  17. 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...

  18. Immune complexes that contain HIV antigens activate peripheral blood T cells.

    Science.gov (United States)

    Korolevskaya, L B; Shmagel, K V; Saidakova, E V; Shmagel, N G; Chereshnev, V A

    2016-07-01

    Uninfected donor T cells were treated in vitro by model immune complexes that contained either HIV or hepatitis C virus (HCV) antigens. Unlike HCV antigen-containing complexes, the immune complexes that contained HIV antigens have been shown to activate peripheral blood T cells of uninfected donors under in vitro conditions. Both the antiviral antibodies and HIV antigen were involved in the activation process. The unique properties of the immune complexes formed by HIV antigens and antiviral antibodies are believed to result from the virus-specific antibody properties and molecular conformation of the antigen-antibody complex. PMID:27595830

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

    Directory of Open Access Journals (Sweden)

    Amy X Yang

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

  20. Antigen-sensitized CD4+CD62Llow memory/effector T helper 2 cells can induce airway hyperresponsiveness in an antigen free setting

    Directory of Open Access Journals (Sweden)

    Nagatani Katsuya

    2005-05-01

    Full Text Available Abstract Background Airway hyperresponsiveness (AHR is one of the most prominent features of asthma, however, precise mechanisms for its induction have not been fully elucidated. We previously reported that systemic antigen sensitization alone directly induces AHR before development of eosinophilic airway inflammation in a mouse model of allergic airway inflammation, which suggests a critical role of antigen-specific systemic immune response itself in the induction of AHR. In the present study, we examined this possibility by cell transfer experiment, and then analyzed which cell source was essential for this process. Methods BALB/c mice were immunized with ovalbumin (OVA twice. Spleen cells were obtained from the mice and were transferred in naive mice. Four days later, AHR was assessed. We carried out bronchoalveolar lavage (BAL to analyze inflammation and cytokine production in the lung. Fluorescence and immunohistochemical studies were performed to identify T cells recruiting and proliferating in the lung or in the gut of the recipient. To determine the essential phenotype, spleen cells were column purified by antibody-coated microbeads with negative or positive selection, and transferred. Then, AHR was assessed. Results Transfer of spleen cells obtained from OVA-sensitized mice induced a moderate, but significant, AHR without airway antigen challenge in naive mice without airway eosinophilia. Immunization with T helper (Th 1 elicited antigen (OVA with complete Freund's adjuvant did not induce the AHR. Transferred cells distributed among organs, and the cells proliferated in an antigen free setting for at least three days in the lung. This transfer-induced AHR persisted for one week. Interleukin-4 and 5 in the BAL fluid increased in the transferred mice. Immunoglobulin E was not involved in this transfer-induced AHR. Transfer of in vitro polarized CD4+ Th2 cells, but not Th1 cells, induced AHR. We finally clarified that CD4+CD62Llow memory

  1. Auto-presentation of Staphylococcal enterotoxin A by mouse CD4+ T cells

    Science.gov (United States)

    The currently accepted model for superantigen (SAg )induced T cell activation suggests that SAg, without being processed, cross links both MHC class II, from Antigen Presenting Cells (APC), and V-beta, from T-cell receptor (TCR), initiating nonspecific T-cell activation. This T-cell proliferation in...

  2. T-cell recognition of a cross-reactive antigen(s) in erythrocyte stages of Plasmodium falciparum and Plasmodium yoelii: inhibition of parasitemia by this antigen(s).

    OpenAIRE

    Lucas, B.; Engels, A; Camus, D; Haque, A.

    1993-01-01

    In the current study, we investigated the presence of a cross-reactive antigen(s) in the erythrocyte stage from Plasmodium yoelii (265 BY strain) and Plasmodium falciparum through recognition by T cells primed in vivo with antigens from each of these parasites. BALB/c mice are naturally resistant to P. falciparum but are susceptible to P. yoelii infection. Mice that had recovered from P. yoelii primary infection became resistant to a second infection. A higher in vitro proliferative response ...

  3. Migratory dendritic cells transfer antigen to a lymph node-resident dendritic cell population for efficient CTL priming.

    Science.gov (United States)

    Allan, Rhys S; Waithman, Jason; Bedoui, Sammy; Jones, Claerwen M; Villadangos, Jose A; Zhan, Yifan; Lew, Andrew M; Shortman, Ken; Heath, William R; Carbone, Francis R

    2006-07-01

    Skin dendritic cells (DCs) are thought to act as key initiators of local T cell immunity. Here we show that after skin infection with herpes simplex virus (HSV), cytotoxic T lymphocyte (CTL) activation required MHC class I-restricted presentation by nonmigratory CD8(+) DCs rather than skin-derived DCs. Despite a lack of direct presentation by migratory DCs, blocking their egress from infected skin substantially inhibited class I-restricted presentation and HSV-specific CTL responses. These results support the argument for initial transport of antigen by migrating DCs, followed by its transfer to the lymphoid-resident DCs for presentation and CTL priming. Given that relatively robust CTL responses were seen with small numbers of skin-emigrant DCs, we propose that this inter-DC antigen transfer functions to amplify presentation across a larger network of lymphoid-resident DCs for efficient T cell activation. PMID:16860764

  4. Effective expansion of forkhead box P3⁺ regulatory T cells via early secreted antigenic target 6 and antigen 85 complex B from Mycobacterium tuberculosis.

    Science.gov (United States)

    Wu, Ying-E; Du, Zhong-Ren; Cai, Ying-Mu; Peng, Wen-Guang; Zheng, Gao-Zhe; Zheng, Geng-Long; Wu, Li-Biao; Li, Ke

    2015-04-01

    The expansion of CD4+ CD25+ forkhead box (FOX)P3+ regulatory T (Treg) cells has been observed in patients with Mycobacterium (M.) tuberculosis; however, the mechanism of expansion remains to be elucidated. The aim of the present study was to examine the role of the early secreted antigenic target 6(ESAT‑6) and antigen 85 complex B (Ag85B) from M. tuberculosis on Treg cell expansion. To investigate the sensitivity of peripheral blood cultures to the M. tuberculosis ESAT‑6 and Ag85B antigens, the proportion of circulating CD4+ CD25+ FOXP3+ Treg cells was determined using flow cytometry and the levels of FOXP3 mRNA were determined using reverse transcription quantitative polymerase chain reaction. The mRNA levels of FOXP3 and the proportion of circulating CD4+ CD25+ FOXP3+ Treg cells were increased in multiplicitous drug‑resistant tuberculosis patients compared with those in healthy controls and patients with latent tuberculosis (TB) infection (LTBI) (Ptuberculosis antigens ESAT‑6 and Ag85B induced CD4+ CD25+ FOXP3+ Treg‑cell expansion, particularly in patients with LTBI. These findings indicated that CD4+ CD25+ FOXP3+ Treg cells may have a primary role in the failure of the host immune system to eradicate M. tuberculosis.

  5. 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...

  6. Expression, Purification and Characterization of Ricin vectors used for exogenous antigen delivery into the MHC Class I presentation pathway

    Directory of Open Access Journals (Sweden)

    Smith Daniel C.

    2003-01-01

    Full Text Available Disarmed versions of the cytotoxin ricin can deliver fused peptides into target cells leading to MHC class I-restricted antigen presentation [Smith et al. J Immunol 2002; 169:99-107]. The ricin delivery vector must contain an attenuated catalytic domain to prevent target cell death, and the fused peptide epitope must remain intact for delivery and functional loading to MHC class I molecules. Expression in E. coli and purification by cation exchange chromatography of the fusion protein is described. Before used for delivery, the activity of the vector must be characterized in vitro, via an N-glycosidase assay, and in vivo, by a cytotoxicity assay. The presence of an intact epitope must be confirmed using mass spectrometry by comparing the actual mass with the predicted mass.

  7. 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...

  8. Overnight resting of PBMC changes functional signatures of antigen specific T- cell responses: impact for immune monitoring within clinical trials.

    Directory of Open Access Journals (Sweden)

    Sarah Kutscher

    Full Text Available Polyfunctional CD4 or CD8 T cells are proposed to represent a correlate of immune control for persistent viruses as well as for vaccine mediated protection against infection. A well-suited methodology to study complex functional phenotypes of antiviral T cells is the combined staining of intracellular cytokines and phenotypic marker expression using polychromatic flow cytometry. In this study we analyzed the effect of an overnight resting period at 37 °C on the quantity and functionality of HIV-1, EBV, CMV, HBV and HCV specific CD4 and CD8 T-cell responses in a cohort of 21 individuals. We quantified total antigen specific T cells by multimer staining and used 10-color intracellular cytokine staining (ICS to determine IFNγ, TNFα, IL2 and MIP1β production. After an overnight resting significantly higher numbers of functionally active T cells were detectable by ICS for all tested antigen specificities, whereas the total number of antigen specific T cells determined by multimer staining remained unchanged. Overnight resting shifted the quality of T-cell responses towards polyfunctionality and increased antigen sensitivity of T cells. Our data suggest that the observed effect is mediated by T cells rather than by antigen presenting cells. We conclude that overnight resting of PBMC prior to ex vivo analysis of antiviral T-cell responses represents an efficient method to increase sensitivity of ICS-based methods and has a prominent impact on the functional phenotype of T cells.

  9. Stable isotope labeling of oligosaccharide cell surface antigens

    Energy Technology Data Exchange (ETDEWEB)

    Unkefer, C.J.; Silks, L.A. III; Martinez, R.A. [and others

    1998-12-31

    The overall goal of this Laboratory Directed Research and Development (LDRD) project was to develop new methods for synthesis of {sup 13}C-labeled oligosaccharides that are required for nuclear magnetic resonance (NMR) studies of their solution conformation. Oligosaccharides are components of the cell`s outer surface and are involved in important processes such as cell-cell recognition and adhesion. Recently, Danishefsky and coworkers at Slone-Kettering Cancer Center developed a method for the solid-phase chemical synthesis of oligosaccharides. The specific goal of this LDRD project was to prepare uniform {sup 13}C-labeled aldohexose precursors required for the solid-phase synthesis of the Lewis blood-group antigenic determinants. We report the synthesis of {sup 13}C-labeled D-glucal, D-galactal and Fucosyl precursors. We have been collaborating with the Danishefsky group on the synthesis of the Lewis oligosaccharides and the NMR analysis of their solution conformation.

  10. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  12. Serological analysis of cell surface antigens of null cell acute lymphocytic leukemia by mouse monoclonal antibodies.

    OpenAIRE

    Ueda, R; Tanimoto, M; Takahashi, T.; Ogata, S; Nishida, K; Namikawa, R.; Nishizuka, Y; Ota, K.

    1982-01-01

    Nine antigens systems were defined. Two were related to HLA-A,B,C and to Ia-like antigens; the others could be grouped into three categories. (i) NL-22, NL-1: NL-22 antibody reacted with leukemia cells from 12 to 16 cases of null cell acute lymphocytic leukemia (null-ALL) but not with any other type of leukemia tested or with lymphoid cells of various origins. Among cultured cell lines tested, one (NALM-6) of three null-ALL cell lines was positive, the others were negative. Absorption analysi...

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

    Science.gov (United States)

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

    2016-08-01

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

  14. Impaired cell surface expression of HLA-B antigens on mesenchymal stem cells and muscle cell progenitors

    DEFF Research Database (Denmark)

    Isa, Adiba; Nehlin, Jan; Sabir, Hardee Jawad;

    2010-01-01

    HLA class-I expression is weak in embryonic stem cells but increases rapidly during lineage progression. It is unknown whether all three classical HLA class-I antigens follow the same developmental program. In the present study, we investigated allele-specific expression of HLA-A, -B, and -C...... at the mRNA and protein levels on human mesenchymal stem cells from bone marrow and adipose tissue as well as striated muscle satellite cells and lymphocytes. Using multicolour flow cytometry, we found high cell surface expression of HLA-A on all stem cells and PBMC examined. Surprisingly, HLA-B was either...... undetectable or very weakly expressed on all stem cells protecting them from complement-dependent cytotoxicity (CDC) using relevant human anti-B and anti-Cw sera. IFNgamma stimulation for 48-72 h was required to induce full HLA-B protein expression. Quantitative real-time RT-PCR showed that IFNgamma induced...

  15. 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

  16. 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

  17. MONOCLONAL-ANTIBODIES TO HUMAN EMBRYONAL CARCINOMA-CELLS - ANTIGENIC RELATIONSHIPS OF GERM-CELL TUMORS

    NARCIS (Netherlands)

    DEWIT, TFR; WILSON, L; VANDENELSEN, PJ; THIELEN, F; BREKHOFF, D; OOSTERHUIS, JW; PERA, MF; STERN, PL

    1991-01-01

    Fifteen monoclonal antibodies (mAb) that show specificity for human embryonal carcinoma cells are described. C57BL/6 mice were immunized with Tera-2 embryonal carcinoma cells, and hybridomas were isolated and tested versus a set of human developmental tumor cell lines. The antigens exhibit relativel

  18. From the Deep Sea to Everywhere: Environmental Antigens for iNKT Cells.

    Science.gov (United States)

    Wingender, Gerhard

    2016-08-01

    Invariant natural killer T (iNKT) cells are a unique subset of innate T cells that share features with innate NK cells and adaptive memory T cells. The first iNKT cell antigen described was found 1993 in a marine sponge and it took over 10 years for other, bacterial antigens to be described. Given the paucity of known bacterial iNKT cell antigens, it appeared as if iNKT cells play a very specialist role in the protection against few, rare and unusual pathogenic bacteria. However, in the last few years several publications painted a very different picture, suggesting that antigens for iNKT cells are found almost ubiquitous in the environment. These environmental iNKT cell antigens can shape the distribution, phenotype and function of iNKT cells. Here, these recent findings will be reviewed and their implications for the field will be outlined. PMID:26703211

  19. 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

    The recognition of many class II major histocompatibility complex (MHC)-associated antigens by T cells requires the participation of the L3T4 molecule. It has been proposed that this molecule acts to stabilize low affinity binding to antigen in association with MHC and thereby increases the avidity...... 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...... the formation of TCR complexes and so prevent activation. However, by increasing the epitope density of the activating ligand, the avidity of the T cell/ligand interaction can be increased sufficiently to prevent this disruption.(ABSTRACT TRUNCATED AT 400 WORDS)...

  20. Present and future of allogeneic natural killer cell therapy

    Directory of Open Access Journals (Sweden)

    Okjae eLim

    2015-06-01

    Full Text Available Natural killer (NK cells are innate lymphocytes that are capable of eliminating tumor cells and are therefore used for cancer therapy. Although many early investigators used autologous NK cells, including lymphokine-activated killer cells, the clinical efficacies were not satisfactory. Meanwhile, human leukocyte antigen (HLA-haploidentical hematopoietic stem cell transplantation revealed the anti-tumor effect of allogeneic NK cells, and HLA-haploidentical, killer cell immunoglobulin-like receptor (KIR ligand-mismatched allogeneic NK cells are currently used for many protocols requiring NK cells. Moreover, allogeneic NK cells from non-HLA-related healthy donors have been recently used in cancer therapy. The use of allogeneic NK cells from non-HLA-related healthy donors allows the selection of donor NK cells with higher flexibility and to prepare expanded, cryopreserved NK cells for instant administration without delay for ex vivo expansion. In cancer therapy with allogeneic NK cells, optimal matching of donors and recipients is important to maximize the efficacy of the therapy. In this review, we summarize the present state of allogeneic NK cell therapy and its future directions.

  1. The role of class I histocompatibility antigens in the regulation of T-cell activation.

    OpenAIRE

    Dasgupta, J D; Cemach, K; Dubey, D P; Yunis, E J; Amos, D. B.

    1987-01-01

    Class I major histocompatibility antigens in humans (HLA antigens) were found to participate in the regulation of T-cell activation and proliferation induced by phytohemagglutinin. W6/32, a monomorphic antibody directed against class I HLA-A,B,C antigens, significantly inhibited the phytohemagglutinin-induced cell proliferation of peripheral blood lymphocytes. Almost complete suppression of cell activation was achieved on a subfraction of peripheral blood lymphocytes enriched in Mo1+ monocyte...

  2. Monoclonal immunoglobulin M antibody to Japanese encephalitis virus that can react with a nuclear antigen in mammalian cells.

    OpenAIRE

    Gould, E A; Chanas, A C; Buckley, A.; Clegg, C S

    1983-01-01

    An immunoglobulin M (IgM) class monoclonal antibody raised against Japanese encephalitis virus reacted with an epitope on the nonstructural virus protein P74 (NV4 in the old nomenclature) of several flaviviruses and also with an antigen present in the nuclei of a variety of mammalian cell types. This antigen had a characteristic granular distribution by immunofluorescence and may correspond to a polypeptide of molecular weight 56,000 seen in nitrocellulose transfers of sodium dodecyl sulfate-...

  3. Exosomes Derived from M. Bovis BCG Infected Macrophages Activate Antigen-Specific CD4+ and CD8+ T Cells In Vitro and In Vivo

    OpenAIRE

    Giri, Pramod K.; Schorey, Jeffrey S.

    2008-01-01

    Activation of both CD4(+) and CD8(+) T cells is required for an effective immune response to an M. tuberculosis infection. However, infected macrophages are poor antigen presenting cells and may be spatially separated from recruited T cells, thus limiting antigen presentation within a granuloma. Our previous studies showed that infected macrophages release from cells small membrane-bound vesicles called exosomes which contain mycobacterial lipid components and showed that these exosomes could...

  4. Antigen transfer from exosomes to dendritic cells as an explanation for the immune enhancement seen by IgE immune complexes.

    Directory of Open Access Journals (Sweden)

    Rebecca K Martin

    Full Text Available IgE antigen complexes induce increased specific T cell proliferation and increased specific IgG production. Immediately after immunization, CD23(+ B cells capture IgE antigen complexes, transport them to the spleen where, via unknown mechanisms, dendritic cells capture the antigen and present it to T cells. CD23, the low affinity IgE receptor, binds IgE antigen complexes and internalizes them. In this study, we show that these complexes are processed onto B-cell derived exosomes (bexosomes in a CD23 dependent manner. The bexosomes carry CD23, IgE and MHC II and stimulate antigen specific T-cell proliferation in vitro. When IgE antigen complex stimulated bexosomes are incubated with dendritic cells, dendritic cells induce specific T-cell proliferation in vivo, similar to IgE antigen complexes. This suggests that bexosomes can provide the essential transfer mechanism for IgE antigen complexes from B cells to dendritic cells.

  5. Phosphorylation of Large T Antigen Regulates Merkel Cell Polyomavirus Replication

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, Jason; Wang, Xin; Tsang, Sabrina H. [Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104 (United States); Jiao, Jing [Department of Pathology and Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA 19104 (United States); You, Jianxin, E-mail: jianyou@mail.med.upenn.edu [Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104 (United States)

    2014-07-08

    Merkel Cell Polyomavirus (MCPyV) was recently discovered as a novel human polyomavirus that is associated with ~80% of Merkel Cell Carcinomas. The Large Tumor antigen (LT) is an early viral protein which has a variety of functions, including manipulation of the cell cycle and initiating viral DNA replication. Phosphorylation plays a critical regulatory role for polyomavirus LT proteins, but no investigation of MCPyV LT phosphorylation has been performed to date. In this report mass spectrometry analysis reveals three unique phosphorylation sites: T271, T297 and T299. In vivo replication assays confirm that phosphorylation of T271 does not play a role in viral replication, while modification at T297 and T299 have dramatic and opposing effects on LT’s ability to initiate replication from the viral origin. We test these mutants for their ability to bind, unwind, and act as a functional helicase at the viral origin. These studies provide a framework for understanding how phosphorylation of LT may dynamically regulate viral replication. Although the natural host cell of MCPyV has not yet been established, this work provides a foundation for understanding how LT activity is regulated and provides tools for better exploring this regulation in both natural host cells and Merkel cells.

  6. Identification of a potent microbial lipid antigen for diverse Natural Killer T cells1

    Science.gov (United States)

    Wolf, Benjamin J.; Tatituri, Raju V. V.; Almeida, Catarina F.; Le Nours, Jérôme; Bhowruth, Veemal; Johnson, Darryl; Uldrich, Adam P.; Hsu, Fong-Fu; Brigl, Manfred; Besra, Gurdyal S.; Rossjohn, Jamie; Godfrey, Dale I.; Brenner, Michael B.

    2016-01-01

    Invariant Natural Killer T (iNKT) cells are a well-characterized CD1d-restricted T cell subset. The availability of potent antigens and tetramers for iNKT cells has allowed this population to be extensively studied and has revealed their central roles in infection, autoimmunity, and tumor immunity. In contrast, diverse Natural Killer T (dNKT) cells are poorly understood because the lipid antigens they recognize are largely unknown. We sought to identify dNKT cell lipid antigen(s) by interrogating a panel of dNKT mouse cell hybridomas with lipid extracts from the pathogen Listeria monocytogenes. We identified Listeria phosphatidylglycerol (PG) as a microbial antigen that was significantly more potent than a previously characterized dNKT cell antigen, mammalian PG. Further, while mammalian PG loaded CD1d tetramers did not stain dNKT cells, the Listeria-derived PG loaded tetramers did. The structure of Listeria PG was distinct from mammalian PG since it contained shorter, fully-saturated anteiso fatty acid lipid tails. CD1d binding lipid displacement studies revealed that the microbial PG antigen binds significantly better to CD1d than counterparts with the same headgroup. These data reveal a highly-potent microbial lipid antigen for a subset of dNKT cells and provide an explanation for its increased antigen potency compared to the mammalian counterpart. PMID:26254340

  7. Regulation of T cell response to leishmania antigens by determinants of histocompatibility leukocyte class I and II molecules

    Directory of Open Access Journals (Sweden)

    Bacellar O.

    1998-01-01

    Full Text Available It has been shown that HLA class I molecules play a significant role in the regulation of the proliferation of T cells activated by mitogens and antigens. We evaluated the ability of mAb to a framework determinant of HLA class I molecules to regulate T cell proliferation and interferon gamma (IFN-g production against leishmania, PPD, C. albicans and tetanus toxoid antigens in patients with tegumentary leishmaniasis and healthy subjects. The anti-major histocompatibility complex (MHC mAb (W6/32 suppressed lymphocyte proliferation by 90% in cultures stimulated with aCD3, but the suppression was variable in cultures stimulated with leishmania antigen. This suppression ranged from 30-67% and was observed only in 5 of 11 patients. IFN-g production against leishmania antigen was also suppressed by anti-HLA class I mAb. In 3 patients IFN-g levels were suppressed by more than 60%, while in the other 2 cultures IFN-g levels were 36 and 10% lower than controls. The suppression by HLA class I mAb to the proliferative response in leishmaniasis patients and in healthy controls varied with the antigens and the patients or donors tested. To determine whether the suppression is directed at antigen presenting cells (APCs or at the responding T cells, experiments with antigen-primed non-adherent cells, separately incubated with W6/32, were performed. Suppression of proliferation was only observed when the W6/32 mAb was added in the presence of T cells. These data provide evidence that a mAb directed at HLA class I framework determinants can suppress proliferation and cytokine secretion in response to several antigens.

  8. Cell-mediated immune response of synovial fluid lymphocytes to ureaplasma antigen in Reiter's syndrome

    Directory of Open Access Journals (Sweden)

    Pavlica Ljiljana

    2003-01-01

    Full Text Available INTRODUCTION Reiter's syndrome (RS is an seronegative arthritis that occurs after urogenital or enteric infection which in addition with occular and/or mucocutaneous manifestations presents complete form of disease. According to previous understanding arthritis in the RS is the reactive one, which means that it is impossible to isolate its causative agent. However, there are the more and more authors suggesting that arthritis in the urogenital form of disease is caused by the infective agent in the affected joint. This suggestion is based on numerous studies on the presence of Chlmaydia trachomatis and Ureaplasma urealyticum in the inflamed joint by using new diagnostic methods in molecular biology published in the recent literature [1-3]. Besides, numerous studies of the humoral and cell-mediated immune response to "triggering" bacteria in the affected joint have supported previous suggestions [4-7]. Aim of the study was to determine whether synovial fluid T-cells specifically recognize the "triggering" bacteria presumably responsible for the Reiter's syndrome. METHOD The 3H-thymidine uptake procedure for measuring lymphocyte responses was applied to lymphocytes derived concurrently from synovial fluid (SF and from peripheral blood (PB [8]. Ureaplasma antigen and mitogen PHA stimulated lymphocytes in 24 RS patients (24 PB samples, 9 SF samples and the results were compared with those found in 10 patients with rheumatoid arthritis (RA (10 PB samples, 5 SF samples. Preparation of ureaplasma antigen. Ureaplasma was cultured on cell-free liquid medium [9]. Sample of 8 ml was heat-inactivated for 15 minutes at 601C and permanently stirred with magnetic mixer. The sample was centrifuged at 2000 x g for 40 minutes and than deposits carefully carried to other sterile glass tubes (Corex and recentrifuged at 9000 x g for 30 minutes. The deposit was washed 3 times in sterile 0.9% NaCl, and final sediment was resuspended in 1.2 ml sterile 0.9% Na

  9. A Fusion Protein between Streptavidin and the Endogenous TLR4 Ligand EDA Targets Biotinylated Antigens to Dendritic Cells and Induces T Cell Responses In Vivo

    Directory of Open Access Journals (Sweden)

    Laura Arribillaga

    2013-01-01

    Full Text Available The development of tools for efficient targeting of antigens to antigen presenting cells is of great importance for vaccine development. We have previously shown that fusion proteins containing antigens fused to the extra domain A from fibronectin (EDA, an endogenous TLR4 ligand, which targets antigens to TLR4-expressing dendritic cells (DC, are highly immunogenic. To facilitate the procedure of joining EDA to any antigen of choice, we have prepared the fusion protein EDAvidin by linking EDA to the N terminus of streptavidin, allowing its conjugation with biotinylated antigens. We found that EDAvidin, as streptavidin, forms tetramers and binds biotin or biotinylated proteins with a Kd ~ 2.6 × 10−14 mol/L. EDAvidin favours the uptake of biotinylated green fluorescent protein by DC. Moreover, EDAvidin retains the proinflammatory properties of EDA, inducing NF-κβ by TLR4-expressing cells, as well as the production of TNF-α by the human monocyte cell line THP1 and IL-12 by DC. More importantly, immunization of mice with EDAvidin conjugated with the biotinylated nonstructural NS3 protein from hepatitis C virus induces a strong anti-NS3 T cell immune response. These results open a new way to use the EDA-based delivery tool to target any antigen of choice to DC for vaccination against infectious diseases and cancer.

  10. A fusion protein between streptavidin and the endogenous TLR4 ligand EDA targets biotinylated antigens to dendritic cells and induces T cell responses in vivo.

    Science.gov (United States)

    Arribillaga, Laura; Durantez, Maika; Lozano, Teresa; Rudilla, Francesc; Rehberger, Federico; Casares, Noelia; Villanueva, Lorea; Martinez, Marta; Gorraiz, Marta; Borrás-Cuesta, Francisco; Sarobe, Pablo; Prieto, Jesús; Lasarte, Juan José

    2013-01-01

    The development of tools for efficient targeting of antigens to antigen presenting cells is of great importance for vaccine development. We have previously shown that fusion proteins containing antigens fused to the extra domain A from fibronectin (EDA), an endogenous TLR4 ligand, which targets antigens to TLR4-expressing dendritic cells (DC), are highly immunogenic. To facilitate the procedure of joining EDA to any antigen of choice, we have prepared the fusion protein EDAvidin by linking EDA to the N terminus of streptavidin, allowing its conjugation with biotinylated antigens. We found that EDAvidin, as streptavidin, forms tetramers and binds biotin or biotinylated proteins with a Kd ~ 2.6 × 10(-14) mol/L. EDAvidin favours the uptake of biotinylated green fluorescent protein by DC. Moreover, EDAvidin retains the proinflammatory properties of EDA, inducing NF- κβ by TLR4-expressing cells, as well as the production of TNF- α by the human monocyte cell line THP1 and IL-12 by DC. More importantly, immunization of mice with EDAvidin conjugated with the biotinylated nonstructural NS3 protein from hepatitis C virus induces a strong anti-NS3 T cell immune response. These results open a new way to use the EDA-based delivery tool to target any antigen of choice to DC for vaccination against infectious diseases and cancer. PMID:24093105

  11. γδ T cells recognize a microbial encoded B cell antigen to initiate a rapid antigen specific Interleukin 17 response

    Science.gov (United States)

    Zeng, Xun; Wei, Yu-ling; Huang, Jun; Newell, Evan W.; Yu, Hongxiang; Kidd, Brian A.; Kuhns, Michael S.; Waters, Ray W.; Davis, Mark M.; Weaver, Casey T.; Chien, Yueh-hsiu

    2012-01-01

    Summary γδ T cells contribute uniquely to host immune defense. However, how they function remains an enigma. Although it is unclear what most γδ T cells recognize, common dogma asserts that they recognize self-antigens. While they are the major initial Interleukin-17 (IL-17) producers in infections, it is unclear what is required to trigger these cells to act. Here, we report that a noted B cell antigen, the algae protein-phycoerythrin (PE) is an antigen for murine and human γδ T cells. PE also stained specific bovine γδ T cells. Employing this specificity, we demonstrated that antigen recognition, but not extensive clonal expansion, was required to activate naïve γδ T cells to make IL-17. In this activated state, γδ T cells gained the ability to respond to cytokine signals that perpetuated the IL-17 production. These results underscore the adaptability of lymphocyte antigen receptors and suggest a previously unrecognized antigen-driven rapid response in protective immunity prior to the maturation of classical adaptive immunity. PMID:22960222

  12. γδ T cells recognize a microbial encoded B cell antigen to initiate a rapid antigen-specific interleukin-17 response.

    Science.gov (United States)

    Zeng, Xun; Wei, Yu-Ling; Huang, Jun; Newell, Evan W; Yu, Hongxiang; Kidd, Brian A; Kuhns, Michael S; Waters, Ray W; Davis, Mark M; Weaver, Casey T; Chien, Yueh-hsiu

    2012-09-21

    γδ T cells contribute uniquely to immune competence. Nevertheless, how they function remains an enigma. It is unclear what most γδ T cells recognize, what is required for them to mount an immune response, and how the γδ T cell response is integrated into host immune defense. Here, we report that a noted B cell antigen, the algae protein phycoerythrin (PE), is a murine and human γδ T cell antigen. Employing this specificity, we demonstrated that antigen recognition activated naive γδ T cells to make interleukin-17 and respond to cytokine signals that perpetuate the response. High frequencies of antigen-specific γδ T cells in naive animals and their ability to mount effector response without extensive clonal expansion allow γδ T cells to initiate a swift, substantial response. These results underscore the adaptability of lymphocyte antigen receptors and suggest an antigen-driven rapid response in protective immunity prior to the maturation of classical adaptive immunity. PMID:22960222

  13. Blockade of LFA-1 augments in vitro differentiation of antigen-induced Foxp3+ Treg cells

    OpenAIRE

    Verhagen, Johan; Wraith, David C.

    2014-01-01

    Adoptive transfer of antigen-specific, in vitro-induced Foxp3+ Treg (iTreg) cells protects against autoimmune disease. To generate antigen-specific iTreg cells at high purity, however, remains a challenge. Whereas polyclonal T cell stimulation with anti-CD3 and anti-CD28 antibody yields Foxp3+ iTreg cells at a purity of 90–95%, antigen-induced iTreg cells typically do not exceed a purity of 65–75%, even in a TCR-transgenic model. In a similar vein to thymic Treg cell selection, iTreg cell dif...

  14. Activation of Type II Cells into Regenerative Stem Cell Antigen-1+ Cells during Alveolar Repair

    Science.gov (United States)

    Kumar, Varsha Suresh; Zhang, Wei; Rehman, Jalees; Malik, Asrar B.

    2015-01-01

    The alveolar epithelium is composed of two cell types: type I cells comprise 95% of the gas exchange surface area, whereas type II cells secrete surfactant, while retaining the ability to convert into type I cells to induce alveolar repair. Using lineage-tracing analyses in the mouse model of Pseudomonas aeruginosa–induced lung injury, we identified a population of stem cell antigen (Sca)-1–expressing type II cells with progenitor cell properties that mediate alveolar repair. These cells were shown to be distinct from previously reported Sca-1–expressing bronchioalveolar stem cells. Microarray and Wnt reporter studies showed that surfactant protein (Sp)-C+Sca-1+ cells expressed Wnt signaling pathway genes, and inhibiting Wnt/β-catenin signaling prevented the regenerative function of Sp-C+Sca-1+ cells in vitro. Thus, P. aeruginosa–mediated lung injury induces the generation of a Sca-1+ subset of type II cells. The progenitor phenotype of the Sp-C+Sca-1+ cells that mediates alveolar epithelial repair might involve Wnt signaling. PMID:25474582

  15. Immature CD4+ dendritic cells conditioned with donor kidney antigen prolong renal allograft survival in rats

    Institute of Scientific and Technical Information of China (English)

    WANG Tao; XU Lin; LI Heng; HUANG Zheng-yu; ZHANG Sheng-ping; MIAO Bin; NA Ning

    2012-01-01

    Background AIIogeneic transplant rejection is currently a major problem encountered during organ transplantation.The dendritic cell (DC) is the most effective powerful known professional antigen-presenting cell,and recent studies have found that DCs can also induce immune tolerance,and avoid or reduce the degree of transplant rejection.The aim of this study was to evaluate the effect of transfused immature CD4+ DCs on renal allografts in the rat model.Methods In this study,we induced CD4+ immature DCs from rat bone marrow cells by a cytokine cocktail.The immature CD4+ DCs were identified by morphological analysis and then the suppressive activity of these cells conditioned with donor kidney antigen was evaluated in vitro and in vivo.Results Immature CD4+ DCs conditioned with donor kidney antigen possessed immunosuppressive activity in vitro and they were able to prolong renal transplant survival in an allograft rat model in vivo.Conclusions Our study provides new information on efficacious renal transplantation,which might be useful for understanding the function of immature CD4+ DCs in modulating renal transplant rejection and improving clinical outcome in future studies.

  16. Kinetics of T cell-activation molecules in response to Mycobacterium tuberculosis antigens

    Directory of Open Access Journals (Sweden)

    Antas Paulo RZ

    2002-01-01

    Full Text Available The phenotypic features acquired subsequent to antigen-specific stimulation in vitro were evaluated by means of the kinetic expressions of CD69 and CD25 activation molecules on T lymphocytes and assayed by flow cytometry in response to PPD, Ag85B, and ferritin in PPD-positive healthy control individuals. In response to PHA, CD69 staining on both CD4+ and CD8+ T cells became initially marked after 4 h, peaked at 24 h, and quickly decreased after 120 h. For CD25, a latter expression was detected around 8 h, having increased after 96 h. As expected, the response rate to the mycobacterial antigens was much lower than that to the mitogen. Positive staining was high after 96 h for CD25 and after 24 h for CD69. CD69 expression was significantly enhanced (p < 0.05 on CD8+ as compared to CD4+ T cells. High levels were also found between 96-120 h. Regarding Ag85B, CD25+ cells were mostly CD4+ instead of CD8+ T cells. Moreover, in response to ferritin, a lower CD25 expression was noted. The present data will allow further characterization of the immune response to new mycobacterial-specific antigens and their evaluation for possible inclusion in developing new diagnostic techniques for tuberculosis as well in a new vaccine to prevent the disease.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  18. 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

  19. In situ Delivery of Antigen to DC-SIGN(+)CD14(+) Dermal Dendritic Cells Results in Enhanced CD8(+) T-Cell Responses.

    Science.gov (United States)

    Fehres, Cynthia M; van Beelen, Astrid J; Bruijns, Sven C M; Ambrosini, Martino; Kalay, Hakan; van Bloois, Louis; Unger, Wendy W J; Garcia-Vallejo, Juan J; Storm, Gert; de Gruijl, Tanja D; van Kooyk, Yvette

    2015-09-01

    CD14(+) dendritic cells (DCs) present in the dermis of human skin represent a large subset of dermal DCs (dDCs) that are considered macrophage-like cells with poor antigen (cross)-presenting capacity and limited migratory potential to the lymph nodes. CD14(+) dDC highly express DC-specific ICAM-3-grabbing non-integrin (DC-SIGN), a receptor containing potent endocytic capacity, facilitating intracellular routing of antigens to major histocompatibility complex I and II (MHC-I andII) loading compartments for the presentation to antigen-specific CD8(+) and CD4(+) T cells. Here we show using a human skin explant model that the in situ targeting of antigens to DC-SIGN using glycan-modified liposomes enhances the antigen-presenting capacity of CD14(+) dDCs. Intradermal vaccination of liposomes modified with the DC-SIGN-targeting glycan Lewis(X), containing melanoma antigens (MART-1 or Gp100), accumulated in CD14(+) dDCs and resulted in enhanced Gp100- or MART-1-specific CD8(+) T-cell responses. Simultaneous intradermal injection of the cytokines GM-CSF and IL-4 as adjuvant enhanced the migration of the skin DCs and increased the expression of DC-SIGN on the CD14(+) and CD1a(+) dDCs. These data demonstrate that human CD14(+) dDCs exhibit potent cross-presenting capacity when targeted in situ through DC-SIGN. PMID:25885805

  20. In situ Delivery of Antigen to DC-SIGN + CD14 + Dermal Dendritic Cells Results in Enhanced CD8 + T-Cell Responses

    NARCIS (Netherlands)

    Fehres, Cynthia M.; Van Beelen, Astrid J.; Bruijns, Sven C M; Ambrosini, Martino; Kalay, Hakan; Van Bloois, Louis; Unger, Wendy W J; Garcia-Vallejo, Juan J.; Storm, G; De Gruijl, Tanja D.; Van Kooyk, Yvette V.

    2015-01-01

    CD14 + dendritic cells (DCs) present in the dermis of human skin represent a large subset of dermal DCs (dDCs) that are considered macrophage-like cells with poor antigen (cross)-presenting capacity and limited migratory potential to the lymph nodes. CD14 + dDC highly express DC-specific ICAM-3-grab

  1. Determining Outdoor CPV Cell Temperature (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Muller, M.

    2011-04-01

    An accurate method is needed for determining cell temperature when measuring CPV modules outdoors. It has been suggested that cell temperature can be calculated though a procedure that shutters sunlight to the cells while measuring the transients in open-circuit voltage (Voc) and heat sink temperature. This presentation documents application of this shutter procedure to multiple CPV modules at NREL. The challenges and limitations are presented along with an alternate approach to measuring CPV cell operating temperature.

  2. Uptake and presentation of myelin basic protein by normal human B cells

    DEFF Research Database (Denmark)

    Brimnes, Marie Klinge; Hansen, Bjarke Endel; Nielsen, Leif Kofoed;

    2014-01-01

    were capable of binding the MS-associated self-antigen myelin basic protein (MBP) and of presenting the immunodominant peptide MBP85-99, as determined by staining with the mAb MK16 recognising the peptide presented by HLA-DR15-positive cells. In the presence of serum, however, the majority of B cells...

  3. 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...

  4. Detection of 2 immunoreactive antigens in the cell wall of Sporothrix brasiliensis and Sporothrix globosa.

    Science.gov (United States)

    Ruiz-Baca, Estela; Hernández-Mendoza, Gustavo; Cuéllar-Cruz, Mayra; Toriello, Conchita; López-Romero, Everardo; Gutiérrez-Sánchez, Gerardo

    2014-07-01

    The cell wall of members of the Sporothrix schenckii complex contains highly antigenic molecules which are potentially useful for the diagnosis and treatment of sporotrichosis. In this study, 2 immunoreactive antigens of 60 (Gp60) and 70 kDa (Gp70) were detected in the cell wall of the yeast morphotypes of Sporothrix brasiliensis and Sporothrix globosa.

  5. Dynamic visualization of dendritic cell-antigen interactions in the skin following transcutaneous immunization.

    Directory of Open Access Journals (Sweden)

    Teerawan Rattanapak

    Full Text Available Delivery of vaccines into the skin provides many advantages over traditional parenteral vaccination and is a promising approach due to the abundance of antigen presenting cells (APC residing in the skin including Langerhans cells (LC and dermal dendritic cells (DDC. However, the main obstacle for transcutaneous immunization (TCI is the effective delivery of the vaccine through the stratum corneum (SC barrier to the APC in the deeper skin layers. This study therefore utilized microneedles (MN and a lipid-based colloidal delivery system (cubosomes as a synergistic approach for the delivery of vaccines to APC in the skin. The process of vaccine uptake and recruitment by specific types of skin APC was investigated in real-time over 4 hours in B6.Cg-Tg (Itgax-EYFP 1 Mnz/J mice by two-photon microscopy. Incorporation of the vaccine into a particulate delivery system and the use of MN preferentially increased vaccine antigen uptake by a highly motile subpopulation of skin APC known as CD207⁺ DC. No uptake of antigen or any response to immunisation by LC could be detected.

  6. Enhanced expression of beta2-microglobulin and HLA antigens on human lymphoid cells by interferon

    DEFF Research Database (Denmark)

    Heron, I; Hokland, M; Berg, K

    1979-01-01

    Mononuclear cells from the blood of healthy normal humans were kept in cultures under nonstimulating conditions for 16 hr in the presence or absence of human interferon. The relative quantities of HLA antigens and beta(2)-microglobulin on the cultured cells were determined by quantitative...... was observed on B- and T-enriched lymphocyte populations and was found to be dose dependent with the optimum with "physiological" concentrations of interferon. Pretreatment of lymphocytes with interferon for 2 hr was found to be as effective as having interferon present during the total culture period...

  7. An improved haemolytic plaque assay for the detection of cells secreting antibody to bacterial antigens

    DEFF Research Database (Denmark)

    Barington, T; Heilmann, C

    1992-01-01

    Recent advances in the development of conjugate polysaccharide vaccines for human use have stimulated interest in the use of assays detecting antibody-secreting cells (AbSC) with specificity for bacterial antigens. Here we present improved haemolytic plaque-forming cell (PFC) assays detecting Ab......SC with specificity for tetanus and diphtheria toxoid as well as for Haemophilus influenzae type b and pneumococcal capsular polysaccharides. These assays were found to be less time consuming, more economical and yielded 1.9-3.4-fold higher plaque numbers than traditional Jerne-type PFC assays. In the case of anti...

  8. Antigen availability determines CD8⁺ T cell-dendritic cell interaction kinetics and memory fate decisions.

    Science.gov (United States)

    Henrickson, Sarah E; Perro, Mario; Loughhead, Scott M; Senman, Balimkiz; Stutte, Susanne; Quigley, Michael; Alexe, Gabriela; Iannacone, Matteo; Flynn, Michael P; Omid, Shaida; Jesneck, Jonathan L; Imam, Sabrina; Mempel, Thorsten R; Mazo, Irina B; Haining, W Nicholas; von Andrian, Ulrich H

    2013-09-19

    T cells are activated by antigen (Ag)-bearing dendritic cells (DCs) in lymph nodes in three phases. The duration of the initial phase of transient, serial DC-T cell interactions is inversely correlated with Ag dose. The second phase, characterized by stable DC-T cell contacts, is believed to be necessary for full-fledged T cell activation. Here we have shown that this is not the case. CD8⁺ T cells interacting with DCs presenting low-dose, short-lived Ag did not transition to phase 2, whereas higher Ag dose yielded phase 2 transition. Both antigenic constellations promoted T cell proliferation and effector differentiation but yielded different transcriptome signatures at 12 hr and 24 hr. T cells that experienced phase 2 developed long-lived memory, whereas conditions without stable contacts yielded immunological amnesia. Thus, T cells make fate decisions within hours after Ag exposure, resulting in long-term memory or abortive effector responses, correlating with T cell-DCs interaction kinetics. PMID:24054328

  9. The uptake of soluble and particulate antigens by epithelial cells in the mouse small intestine.

    Science.gov (United States)

    Howe, Savannah E; Lickteig, Duane J; Plunkett, Kyle N; Ryerse, Jan S; Konjufca, Vjollca

    2014-01-01

    Intestinal epithelial cells (IECs) overlying the villi play a prominent role in absorption of digested nutrients and establish a barrier that separates the internal milieu from potentially harmful microbial antigens. Several mechanisms by which antigens of dietary and microbial origin enter the body have been identified; however whether IECs play a role in antigen uptake is not known. Using in vivo imaging of the mouse small intestine, we investigated whether epithelial cells (enterocytes) play an active role in the uptake (sampling) of lumen antigens. We found that small molecular weight antigens such as chicken ovalbumin, dextran, and bacterial LPS enter the lamina propria, the loose connective tissue which lies beneath the epithelium via goblet cell associated passageways. However, epithelial cells overlying the villi can internalize particulate antigens such as bacterial cell debris and inert nanoparticles (NPs), which are then found co-localizing with the CD11c+ dendritic cells in the lamina propria. The extent of NP uptake by IECs depends on their size: 20-40 nm NPs are taken up readily, while NPs larger than 100 nm are taken up mainly by the epithelial cells overlying Peyer's patches. Blocking NPs with small proteins or conjugating them with ovalbumin does not inhibit their uptake. However, the uptake of 40 nm NPs can be inhibited when they are administered with an endocytosis inhibitor (chlorpromazine). Delineating the mechanisms of antigen uptake in the gut is essential for understanding how tolerance and immunity to lumen antigens are generated, and for the development of mucosal vaccines and therapies.

  10. Group-specific human granulocyte antigens on a chronic myelogenous leukemia cell line with a Philadelphia chromosome marker.

    Science.gov (United States)

    Drew, S I; Terasaki, P I; Billing, R J; Bergh, O J; Minowada, J; Klein, E

    1977-05-01

    Group-specific human granulocyte antigens are serologically detectable with granulocytotoxic-positive human alloantisera on a cell line, K562, of chronic myelogenous leukemia origin which bears a Philadelphia chromosomal marker. The same cell line lacks serologically detectable HLA, B2 microglobulin, and B-lymphocyte antigens. Granulocyte antigens are important cell markers for cell lines of suspected myeloid lineage.

  11. Gamma delta T cells recognize a microbial encoded B Cell antigen to initiate a rapid antigen-specific Interleukin-17 response

    Science.gov (United States)

    Gamma delta T cells contribute uniquely to host immune defense, but the way in which they do so remains an enigma. Here we show that an algae protein, phycoerythrin (PE) is recognized by gamma delta T cells from mice, bovine and humans and binds directly to specific gamma delta T cell antigen recept...

  12. The T cell antigen receptor: the Swiss army knife of the immune system.

    Science.gov (United States)

    Attaf, M; Legut, M; Cole, D K; Sewell, A K

    2015-07-01

    The mammalian T cell receptor (TCR) orchestrates immunity by responding to many billions of different ligands that it has never encountered before and cannot adapt to at the protein sequence level. This remarkable receptor exists in two main heterodimeric isoforms: αβ TCR and γδ TCR. The αβ TCR is expressed on the majority of peripheral T cells. Most αβ T cells recognize peptides, derived from degraded proteins, presented at the cell surface in molecular cradles called major histocompatibility complex (MHC) molecules. Recent reports have described other αβ T cell subsets. These 'unconventional' T cells bear TCRs that are capable of recognizing lipid ligands presented in the context of the MHC-like CD1 protein family or bacterial metabolites bound to the MHC-related protein 1 (MR1). γδ T cells constitute a minority of the T cell pool in human blood, but can represent up to half of total T cells in tissues such as the gut and skin. The identity of the preferred ligands for γδ T cells remains obscure, but it is now known that this receptor can also functionally engage CD1-lipid, or immunoglobulin (Ig) superfamily proteins called butyrophilins in the presence of pyrophosphate intermediates of bacterial lipid biosynthesis. Interactions between TCRs and these ligands allow the host to discriminate between self and non-self and co-ordinate an attack on the latter. Here, we describe how cells of the T lymphocyte lineage and their antigen receptors are generated and discuss the various modes of antigen recognition by these extraordinarily versatile receptors.

  13. T cells expressing VHH-directed oligoclonal chimeric HER2 antigen receptors

    DEFF Research Database (Denmark)

    Jamnani, Fatemeh Rahimi; Rahbarizadeh, Fatemeh; Shokrgozar, Mohammad Ali;

    2014-01-01

    Adoptive cell therapy with engineered T cells expressing chimeric antigen receptors (CARs) originated from antibodies is a promising strategy in cancer immunotherapy. Several unsuccessful trials, however, highlight the need for alternative conventional binding domains and the better combination...

  14. Human antibodies targeting cell surface antigens overexpressed by the hormone refractory metastatic prostate cancer cells: ICAM-1 is a tumor antigen that mediates prostate cancer cell invasion

    OpenAIRE

    Conrad, Fraser; Zhu, Xiaodong; Zhang, Xin; Chalkley, Robert J.; Burlingame, Alma L; Marks, James D.; Liu, Bin

    2009-01-01

    Transition from hormone-sensitive to hormone-refractory metastatic tumor types poses a major challenge for prostate cancer treatment. Tumor antigens that are differentially expressed during this transition are likely to play important roles in imparting prostate cancer cells with the ability to grow in a hormone-deprived environment and to metastasize to distal sites such as the bone and thus, are likely targets for therapeutic intervention. To identify those molecules and particularly cell s...

  15. Amiloride enhances antigen specific CTL by faciliting HBV DNA vaccine entry into cells.

    Directory of Open Access Journals (Sweden)

    Shuang Geng

    Full Text Available The induction of relatively weak immunity by DNA vaccines in humans can be largely attributed to the low efficiency of transduction of somatic cells. Although formulation with liposomes has been shown to enhance DNA transduction of cultured cells, little, if any, effect is observed on the transduction of somatic tissues and cells. To improve the rate of transduction, DNA vaccine delivery by gene gun and the recently developed electroporation techniques have been employed. We report here that to circumvent requirement for such equipment, amiloride, a drug that is prescribed for hypertension treatment, can accelerate plasmid entry into antigen presenting cells (APCs both in vitro and in vivo. The combination induced APCs more dramatically in both maturation and cytokine secretion. Amiloride enhanced development of full CD8 cytolytic function including induction of high levels of antigen specific CTL and expression of IFN-γ+perforin+granzymeB+ in CD8+ T cells. Thus, amiloride is a facilitator for DNA transduction into host cells which in turn enhances the efficiency of the immune responses.

  16. Epithelial membrane antigen in cells from the uterine cervix: immunocytochemical staining of cervical smears.

    OpenAIRE

    Valkova, B; Ormerod, M G; Moncrieff, D.; Coleman, D V

    1984-01-01

    Smears made from cervical scrapes have been stained immunocytochemically for epithelial membrane antigen using a polyclonal antiserum and two monoclonal antibodies. With the polyclonal antiserum malignant cells and those showing dysplasia consistently expressed the antigen. Normal cells were generally negative, with the exception of some metaplastic cells. The monoclonal antibodies, although they stained the abnormal cells less consistently, gave the same pattern of staining. All three antibo...

  17. Cell Wall-Associated Protein Antigens of Streptococcus salivarius: Purification, Properties, and Function in Adherence

    Science.gov (United States)

    Weerkamp, Anton H.; Jacobs, Ton

    1982-01-01

    Three cell wall-associated protein antigens (antigens b, c, and d) were isolated from mutanolysin-solubilized cell walls of Streptococcus salivarius HB and purified to apparent homogeneity by a combination of ion-exchange chromatography, gel filtration, and immunoadsorption chromatography. Antigens b and c were also isolated from culture supernatants. Antigen b consisted of more than 80% protein and had an apparent molecular weight as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of 320,000. Antigen c consisted of 57% protein, about 30% neutral sugar, and about 13% amino sugar, and its glycoprotein nature was confirmed by specific staining techniques. During sodium dodecyl sulfate-polyacrylamide gel electrophoresis antigen c resolved into two or more bands, depending on the source or the isolation procedure, in the molecular weight range from 220,000 to 280,000. Antigen d consisted of 95% protein and was observed in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as two bands with molecular weights of 129,000 and 121,000. Under nondenaturing conditions all three antigens had molecular weights in the range from 1 × 106 to 3 × 106 as determined by gel filtration. The amino acid compositions of antigens b, c, and d were characterized by low amounts of basic amino acids and relatively high levels of nonpolar amino acids. Among oral streptococcal species antigens b and c were virtually restricted to strains of S. salivarius and most often to serotype I strains. Antigen b was recognized as the factor that mediates coaggregation of S. salivarius with Veillonella strains. The purified protein retained its biological activity. Antigen c could be linked to functions relating to adhesion of the streptococci to host tissues on the basis of its absence in mutant strains and blocking by specific antisera. The purified molecule had no detectable biological activity. Antigen d could not be linked to an established adhesion function. Images

  18. An indirect immunofluorescence assay using a cell culture-derived antigen for detection of antibodies to the agent of human granulocytic ehrlichiosis.

    OpenAIRE

    Nicholson, W L; Comer, J A; Sumner, J W; Gingrich-Baker, C; Coughlin, R T; Magnarelli, L A; Olson, J G; Childs, J. E.

    1997-01-01

    An indirect immunofluorescence assay for the detection of human antibodies to the agent of human granulocytic ehrlichiosis (HGE) was developed and standardized. Antigen was prepared from a human promyelocytic leukemia cell line (HL-60) infected with a tick-derived isolate of the HGE agent (USG3). Suitable antigen presentation and preservation of cellular morphology were obtained when infected cells were applied and cultured on the slide, excess medium was removed, and cells were fixed with ac...

  19. Vaccination with human induced pluripotent stem cells creates an antigen-specific immune response against HIV-1 gp160

    Directory of Open Access Journals (Sweden)

    Shinji eYoshizaki

    2011-02-01

    Full Text Available Induced pluripotent stem cells (iPSCs are artificially derived from somatic cells that have been transduced with defined reprogramming factors. A previous report has indicated the possibility of using iPSCs as an immune stimulator to generate antigen-specific immunity. In our current study, we have investigated whether human iPSCs (hiPSCs have the ability to enhance specific immune response against a human immunodeficiency virus type 1 (HIV-1 antigen in a xenogenic mouse model. Our results show that BALB/c mice immunized with hiPSCs transduced with an adenoviral vector encoding HIV-1 gp160 exhibited prominent antigen-specific cellular immune responses. We further found that pre-treatment of hiPSCs with ionizing radiation promotes the secretion of pro-inflammatory cytokines such as interleukin-1 alpha (IL-1α, IL-12 and IL-18. These cytokines might promote the activation of antigen-presenting cells and the effective induction of cellular immunity. Our present findings thus demonstrate that a hiPSCs-based vaccine has the potential to generate cellular immunity against viral antigens such as HIV-1 gp160 in a xenogenic condition.

  20. Flow Cytometric Analysis of T, B, and NK Cells Antigens in Patients with Mycosis Fungoides.

    Science.gov (United States)

    Yazıcı, Serkan; Bülbül Başkan, Emel; Budak, Ferah; Oral, Barbaros; Adim, Şaduman Balaban; Ceylan Kalin, Zübeyde; Özkaya, Güven; Aydoğan, Kenan; Saricaoğlu, Hayriye; Tunali, Şükran

    2015-01-01

    We retrospectively analyzed the clinicopathological correlation and prognostic value of cell surface antigens expressed by peripheral blood mononuclear cells in patients with mycosis fungoides (MF). 121 consecutive MF patients were included in this study. All patients had peripheral blood flow cytometry as part of their first visit. TNMB and histopathological staging of the cases were retrospectively performed in accordance with International Society for Cutaneous Lymphomas/European Organization of Research and Treatment of Cancer (ISCL/EORTC) criteria at the time of flow cytometry sampling. To determine prognostic value of cell surface antigens, cases were divided into two groups as stable and progressive disease. 17 flow cytometric analyses of 17 parapsoriasis (PP) and 11 analyses of 11 benign erythrodermic patients were included as control groups. Fluorescent labeled monoclonal antibodies were used to detect cell surface antigens: T cells (CD3(+), CD4(+), CD8(+), TCRαβ(+), TCRγδ(+), CD7(+), CD4(+)CD7(+), CD4(+)CD7(-), and CD71(+)), B cells (HLA-DR(+), CD19(+), and HLA-DR(+)CD19(+)), NKT cells (CD3(+)CD16(+)CD56(+)), and NK cells (CD3(-)CD16(+)CD56(+)). The mean value of all cell surface antigens was not statistically significant between parapsoriasis and MF groups. Along with an increase in cases of MF stage statistically significant difference was found between the mean values of cell surface antigens. Flow cytometric analysis of peripheral blood cell surface antigens in patients with mycosis fungoides may contribute to predicting disease stage and progression. PMID:26788525

  1. Intravacuolar Membranes Regulate CD8 T Cell Recognition of Membrane-Bound Toxoplasma gondii Protective Antigen

    Directory of Open Access Journals (Sweden)

    Jodie Lopez

    2015-12-01

    Full Text Available Apicomplexa parasites such as Toxoplasma gondii target effectors to and across the boundary of their parasitophorous vacuole (PV, resulting in host cell subversion and potential presentation by MHC class I molecules for CD8 T cell recognition. The host-parasite interface comprises the PV limiting membrane and a highly curved, membranous intravacuolar network (IVN of uncertain function. Here, using a cell-free minimal system, we dissect how membrane tubules are shaped by the parasite effectors GRA2 and GRA6. We show that membrane association regulates access of the GRA6 protective antigen to the MHC I pathway in infected cells. Although insertion of GRA6 in the PV membrane is key for immunogenicity, association of GRA6 with the IVN limits presentation and curtails GRA6-specific CD8 responses in mice. Thus, membrane deformations of the PV regulate access of antigens to the MHC class I pathway, and the IVN may play a role in immune modulation.

  2. Distinct populations of dendritic cells are present in the subepithelial dome and T cell regions of the murine Peyer's patch

    Science.gov (United States)

    1996-01-01

    Despite the fact that the Peyer's patch (PP) is the primary site for antigen uptake in the intestine, the cellular basis of antigen handling after transport into the PP is poorly understood. We performed immunohistology of murine PPs using the dendritic cell (DC)-reactive monoclonal antibodies N418, NLDC-145, M342, and 2A1, as well as antibodies to other T cell, B cell, and macrophage markers. N418+, 2A1+, NLDC-145-, M342- cells form a dense layer of cells in the subepithelial dome (SED), just beneath the follicle epithelium, and are scattered throughout the follicle, sparing the germinal center. In contrast, N418+, 2A1+, NLDC-145+, and M342+ DCs are present in the interfollicular T cell regions (IFR). CD3+ and CD4+, but no CD8+ T cells were present in the SED and the follicle, including the germinal center, while CD3+, CD4+, and CD8+ T cells were present in the IFR. B cells and macrophages were poorly represented in the SED as no B220+ cells, only few Mac-1lo cells, and no F4/80+ cells were present at this site. In contrast, Mac-1hi cells were found in the IFR and lamina propria of intestinal villi, while F4/80+ cells were found only in the latter. In further phenotypic studies, we analyzed surface molecules of PP and spleen DCs by flow cytometry and found that these cells had similar fluorescence profiles when stained with N418, NLDC-145, and 33D1 DC-reactive antibodies, and antibodies to the costimulatory molecules B7-1 (1G10) and B7-2 (GL1). In contrast, PP DCs expressed 5- 10-fold higher levels of major histocompatibility complex class II antigens (IEk) than spleen DCs. Finally, in functional studies, we demonstrated that both PP and spleen DCs process soluble protein antigens during overnight culture and induce similar levels of proliferation in CD3+ T cells, and CD4+/Mel 14hi T cells from T cell receptor transgenic mice. The in vivo relevance of such presentation was shown by the fact that PP DCs isolated from Balb/c mice after being fed ovalbumin stimulated

  3. HLA-DR, DQ and T cell antigen receptor constant beta genes in Japanese patients with ulcerative colitis.

    Science.gov (United States)

    Kobayashi, K; Atoh, M; Konoeda, Y; Yagita, A; Inoko, H; Sekiguchi, S

    1990-01-01

    We studied the T cell antigen receptor (TcR) constant beta chain genes on HLA typed Japanese patients with ulcerative colitis (UC). A TcR constant beta EcoRI 6.0-kb fragment was present in all Japanese UC patients (n = 17) but completely absent in the controls (n = 35) (chi2 = 47.6, P less than 0.001). The frequency of HLA-DR2 antigen was significantly higher in UC patients (85% versus 28% in controls, P less than 0.001). Furthermore, HLA-DQw1 antigen was also increased in UC patients (96% versus 60% in controls, P less than 0.001). However, HLA-DR4 antigen was significantly decreased in UC patients (12% versus 37%, P = 0.02). HLA-DR1 antigen was not found in UC patients and was present in only 15% of the controls. These results suggest that TcR beta chain and HLA-DQw1 antigen may be important in the pathogenesis of Japanese UC. Images Fig. 1 PMID:1973647

  4. 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.

  5. Variability in expression of cell surface antigens of Candida albicans during morphogenesis.

    OpenAIRE

    Brawner, D L; Cutler, J. E.

    1986-01-01

    The location and expression of two different cell surface antigens on germinating and nongerminating Candida albicans cells was examined by using transmission electron microscopy after labeling with monoclonal antibodies (H9 or C6) and immunocolloidal gold. Immunodeterminant expression of the two carbohydrate antigens was followed from early germination events through 20 h of development. The determinant detected by H9 antibody, which was initially lost from the mother cell surface and prefer...

  6. Regulation of murine macrophage Ia-antigen expression by products of activated spleen cells

    OpenAIRE

    1980-01-01

    This investigation examined the effects of mediators derived form activated spleen cells on macrophage Ia-antigen expression and function. Incubation of adherent thioglycollate-induced murine peritoneal macrophages(> 90% Ia-) with concanavalin A (Con A)- stimulated spleen cell supernate (Con A sup) resulted in a dose- dependent increase in the percentage of Ia-containing (Ia+) phagocytic cells, as detected by antiserum-and-complement-mediated cytotoxicity. The Ia-antigen expression of macroph...

  7. Merkel Cell Polyomavirus Large T Antigen Has Growth-Promoting and Inhibitory Activities

    OpenAIRE

    Cheng, Jingwei; Rozenblatt-Rosen, Orit; Paulson, Kelly G.; Nghiem, Paul; DeCaprio, James A.

    2013-01-01

    Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer. In at least 80% of all MCC, Merkel cell polyomavirus (MCPyV) DNA has undergone clonal integration into the host cell genome, and most tumors express the MCPyV large and small T antigens. In all cases of MCC reported to date, the integrated MCPyV genome has undergone mutations in the large T antigen. These mutations result in expression of a truncated large T antigen that retains the Rb binding or LXCXE motif but deletes...

  8. Lung adenocarcinoma with clear cell features producing carbohydrate antigen 19-9.

    Science.gov (United States)

    Goto, Taichiro; Hada, Masao; Oyama, Toshio

    2015-10-01

    A 76-year-old man underwent surgery for lung cancer. Histopathologically, most of the resected tumor was composed of polygonal cells with foamy cytoplasm, and the cells were arranged predominantly in acinar patterns. In this case, although the carbohydrate antigen 19-9 level was high before surgery, it normalized after resection. The tumor was considered a carbohydrate antigen 19-9-producing tumor, which was further supported by the results of immunohistochemical analysis. Adenocarcinoma with clear cell features, producing carbohydrate antigen 19-9, is an exceedingly rare entity.

  9. Red Blood Cell Antigen Genotyping for Sickle Cell Disease, Thalassemia, and Other Transfusion Complications.

    Science.gov (United States)

    Fasano, Ross M; Chou, Stella T

    2016-10-01

    Since the discovery of the ABO blood group in the early 20th century, more than 300 blood group antigens have been categorized among 35 blood group systems. The molecular basis for most blood group antigens has been determined and demonstrates tremendous genetic diversity, particularly in the ABO and Rh systems. Several blood group genotyping assays have been developed, and 1 platform has been approved by the Food and Drug Administration as a "test of record," such that no phenotype confirmation with antisera is required. DNA-based red blood cell (RBC) phenotyping can overcome certain limitations of hemagglutination assays and is beneficial in many transfusion settings. Genotyping can be used to determine RBC antigen phenotypes in patients recently transfused or with interfering allo- or autoantibodies, to resolve discrepant serologic typing, and/or when typing antisera are not readily available. Molecular RBC antigen typing can facilitate complex antibody evaluations and guide RBC selection for patients with sickle cell disease (SCD), thalassemia, and autoimmune hemolytic anemia. High-resolution RH genotyping can identify variant RHD and RHCE in patients with SCD, which have been associated with alloimmunization. In the future, broader access to cost-efficient, high-resolution RBC genotyping technology for both patient and donor populations may be transformative for the field of transfusion medicine. PMID:27345938

  10. Immunoregulatory adherent cells in human tuberculosis: radiation-sensitive antigen-specific suppression by monocytes

    Energy Technology Data Exchange (ETDEWEB)

    Kleinhenz, M.E.; Ellner, J.J.

    1985-07-01

    In human tuberculosis, adherent mononuclear cells (AMC) selectively depress in vitro responses to the mycobacterial antigen tuberculin purified protein derivative (PPD). The phenotype of this antigen-specific adherent suppressor cell was characterized by examining the functional activity of adherent cells after selective depletion of sheep erythrocyte-rosetting T cells or OKM1-reactive monocytes. Adherent cell suppression was studied in the (/sup 3/H)thymidine-incorporation microculture assay by using T cells rigorously depleted of T cells with surface receptors for the Fc portion of IgG (T gamma cells) as antigen-responsive cells. PPD-induced (/sup 3/H)thymidine incorporation by these non gamma T cells was uniformly reduced (mean, 42% +/- 10% (SD)) when autologous AMC were added to non gamma T cells at a ratio of 1:2. Antigen-specific suppression by AMC was not altered by depletion of sheep erythrocyte-rosetting T cells or treatment with indomethacin. However, AMC treated with OKM1 and complement or gamma irradiation (1,500 rads) no longer suppressed tuberculin responses in vitro. These studies identify the antigen-specific adherent suppressor cell in tuberculosis as an OKM1-reactive, non-erythrocyte-rosetting monocyte. The radiosensitivity of this monocyte immunoregulatory function may facilitate its further definition.

  11. Exosomes derived from M. Bovis BCG infected macrophages activate antigen-specific CD4+ and CD8+ T cells in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Pramod K Giri

    Full Text Available Activation of both CD4(+ and CD8(+ T cells is required for an effective immune response to an M. tuberculosis infection. However, infected macrophages are poor antigen presenting cells and may be spatially separated from recruited T cells, thus limiting antigen presentation within a granuloma. Our previous studies showed that infected macrophages release from cells small membrane-bound vesicles called exosomes which contain mycobacterial lipid components and showed that these exosomes could stimulate a pro-inflammatory response in naïve macrophages. In the present study we demonstrate that exosomes stimulate both CD4(+ and CD8(+ splenic T cells isolated from mycobacteria-sensitized mice. Although the exosomes contain MHC I and II as well as costimulatory molecules, maximum stimulation of T cells required prior incubation of exosomes with antigen presenting cells. Exosomes isolated from M. bovis and M. tuberculosis infected macrophages also stimulated activation and maturation of mouse bone marrow-derived dendritic cells. Interestingly, intranasal administration of mice with exosomes isolated from M. bovis BCG infected macrophages induce the generation of memory CD4(+ and CD8(+ T cells. The isolated T cells also produced IFN-gamma upon restimulation with BCG antigens. The release of exosomes from infected macrophages may overcome some of the defects in antigen presentation associated with mycobacterial infections and we suggest that exosomes may be a promising M. tuberculosis vaccine candidate.

  12. Serum antibodies to whole-cell and recombinant antigens of Borrelia burgdorferi in cottontail rabbits.

    Science.gov (United States)

    Magnarelli, Louis A; Norris, Steven J; Fikrig, Erol

    2012-01-01

    Archived serum samples, from 95 eastern cottontail rabbits (Sylvilagus floridanus) captured in New York, New York, USA and Millbrook, New York, USA, during 1985-86, were analyzed in solid-phase enzyme-linked immunosorbent assays (ELISA) for total and class-specific immunoglobulin (Ig) M antibodies to whole-cell or recombinant antigens of Borrelia burgdorferi sensu stricto. Using a polyvalent conjugate, rabbit sera contained antibodies to whole-cell and recombinant antigens (protein [p]35, p37, or VlsE) during different seasons, but there was no reactivity to outer surface protein (Osp)A or OspB. Seventy-six of the 102 sera (75%) analyzed were reactive with one or more of the antigens; 61 of the positive samples (80%) reacted to whole-cell antigens, followed by results for the p35 (58%, 44/76), VlsE (43%, 33/76), and p37 (29%, 22/ 76) antigens. Fifty-eight sera (76%) contained antibodies to the VlsE or p35 antigens with or without reactivity to whole-cell antigens. High antibody titers (≥1:2,560) recorded for 52 sera indicate robust antibody production. In analyses for IgM antibodies in an ELISA containing whole-cell antigens, there were 30 positive sera; titers ranged from 1:160 to 1:640. There was minimal cross-reactivity when rabbit antisera to Treponema pallidum or four serovars of Leptospira interrogans were screened against B. burgdorferi antigens. Based on more-specific results, VlsE and p35 antigens appear to be useful markers for detecting possible B. burgdorferi infections. PMID:22247369

  13. ACTIVATION OF CELLS FROM HYPOTHALAMIC STRUCTURES AFTER INJECTION OF ANTIGENS DIFFERENT IN THEIR NATURE (by the c-Fos expression

    Directory of Open Access Journals (Sweden)

    S. V. Perekrest

    2006-01-01

    Full Text Available Abstract. Activation levels of hypothalamic structures (AHN, PVH, DMH, VMH, LHA, PH were analyzed within first hours after injection of antigens [lipopolysaccharide (LPS and bovine serum albumine [BSA]. For all investigated hypothalamic structures, an increase of c-Fos positive cells numbers was observed after injection of the antigens, as compared to the controls. LPS injection caused activation of more multiple neuron populations. AHN, PVH, LHA, and PH structures exhibited the highest levels of c-Fos activation upon LPS application. BSA injection induced activation of lesser cells quantities, but their enrichment in c-Fos protein was higher, thus resulting into increased optical density of VMH, LHA and PH neurons. Hence, the present work has shown that activation pattern of hypothalamic structures differs upon application of antigens that are different by their origin.

  14. Impaired cell surface expression of HLA-B antigens on mesenchymal stem cells and muscle cell progenitors.

    Directory of Open Access Journals (Sweden)

    Adiba Isa

    Full Text Available HLA class-I expression is weak in embryonic stem cells but increases rapidly during lineage progression. It is unknown whether all three classical HLA class-I antigens follow the same developmental program. In the present study, we investigated allele-specific expression of HLA-A, -B, and -C at the mRNA and protein levels on human mesenchymal stem cells from bone marrow and adipose tissue as well as striated muscle satellite cells and lymphocytes. Using multicolour flow cytometry, we found high cell surface expression of HLA-A on all stem cells and PBMC examined. Surprisingly, HLA-B was either undetectable or very weakly expressed on all stem cells protecting them from complement-dependent cytotoxicity (CDC using relevant human anti-B and anti-Cw sera. IFNgamma stimulation for 48-72 h was required to induce full HLA-B protein expression. Quantitative real-time RT-PCR showed that IFNgamma induced a 9-42 fold increase of all six HLA-A,-B,-C gene transcripts. Interestingly, prior to stimulation, gene transcripts for all but two alleles were present in similar amounts suggesting that post-transcriptional mechanisms regulate the constitutive expression of HLA-A,-B, and -C. Locus-restricted expression of HLA-A, -B and -C challenges our current understanding of the function of these molecules as regulators of CD8(+ T-cell and NK-cell function and should lead to further inquiries into their expression on other cell types.

  15. Chimeric Antigen Receptor T Cell (Car T Cell Therapy In Hematology

    Directory of Open Access Journals (Sweden)

    Pinar Ataca

    2015-12-01

    Full Text Available It is well demonstrated that immune system can control and eliminate cancer cells. Immune-mediated elimination of tumor cells has been discovered and is the basis of both cancer vaccines and cellular therapies including hematopoietic stem cell transplantation (HSCT. Adoptive T cell transfer has been improved to be more specific and potent and cause less off-target toxicities. Currently, there are two forms of engineered T cells being tested in clinical trials: T cell receptor (TCR and chimeric antigen receptor (CAR modified T cells. On July 1, 2014, the United States Food and Drug Administration granted ‘breakthrough therapy’ designation to anti-CD19 CAR T cell therapy. Many studies were conducted to evaluate the beneficiaries of this exciting and potent new treatment modality. This review summarizes the history of adoptive immunotherapy, adoptive immunotherapy using CARs, the CAR manufacturing process, preclinical-clinical studies, effectiveness and drawbacks of this strategy.

  16. Docking of B-cell epitope antigen to specific hepatitis B antibody

    Indian Academy of Sciences (India)

    R Rajkannan; E J Padma Malar

    2007-09-01

    The interaction of pres1 region of hepatitis B virus B-cell epitope antigen with specific hepatitis B neutralizing monoclonal antibody was examined by docking study. We modelled the 3D complex structure of B-cell epitope antigen residues CTTPAQGNSMFPSCCCTKPTDGNCY by homology modelling and docked it with the crystal structure of monoclonal antibody specific for the pres1 region of the hepatitis B virus. At the optimized docked conformation, the interactions between the amino acids of antigen and antibody were examined. It is found that the docked complex is stabilized by 59.3 kcal/mol. The stability of the docked antigen-antibody complex is due to hydrogen bonding and van der Waals interactions. The amino acids of the antigen and antibody responsible for the interaction were identified.

  17. Different-Sized Gold Nanoparticle Activator/Antigen Increases Dendritic Cells Accumulation in Liver-Draining Lymph Nodes and CD8+ T Cell Responses.

    Science.gov (United States)

    Zhou, Qianqian; Zhang, Yulong; Du, Juan; Li, Yuan; Zhou, Yong; Fu, Qiuxia; Zhang, Jingang; Wang, Xiaohui; Zhan, Linsheng

    2016-02-23

    The lack of efficient antigen and activator delivery systems, as well as the restricted migration of dendritic cells (DCs) to secondary lymph organs, dramatically limits DC-based adoptive immunotherapy. We selected two spherical gold nanoparticle (AuNP)-based vehicles of optimal size for activator and antigen delivery. Their combination (termed the NanoAu-Cocktail) was associated with the dual targeting of CpG oligonucleotides (CpG-ODNs) and an OVA peptide (OVAp) to DC subcellular compartments, inducing enhanced antigen cross-presentation, upregulated expression of costimulatory molecules and elevated secretion of T helper1 cytokines. We demonstrated that the intravenously transfused NanoAu-Cocktail pulsed DCs showed dramatically improved in vivo homing ability to lymphoid tissues and were settled in T cell area. Especially, by tissue-distribution analysis, we found that more than 60% of lymphoid tissues-homing DCs accumulated in liver-draining lymph nodes (LLNs). The improved homing ability of NanoAu-Cocktail pulsed DCs was associated with the high expression of chemokine receptor 7 (CCR7) and rearrangement of the cytoskeletons. In addition, by antigen-specific tetramers detection, NanoAu-Cocktail pulsed DCs were proved able to elicit strong antigen-specific CD8+ T cell responses, which provided enhanced protection from viral invasions. This study highlights the importance of codelivering antigen/adjuvant using different sized gold nanoparticles to improve DC homing and therapy. PMID:26771692

  18. Nonclassical antigen-processing pathways are required for MHC class II-restricted direct tumor recognition by NY-ESO-1-specific CD4(+) T cells.

    Science.gov (United States)

    Matsuzaki, Junko; Tsuji, Takemasa; Luescher, Immanuel; Old, Lloyd J; Shrikant, Protul; Gnjatic, Sacha; Odunsi, Kunle

    2014-04-01

    Tumor antigen-specific CD4(+) T cells that directly recognize cancer cells are important for orchestrating antitumor immune responses at the local tumor sites. However, the mechanisms of direct MHC class II (MHC-II) presentation of intracellular tumor antigen by cancer cells are poorly understood. We found that two functionally distinct subsets of CD4(+) T cells were expanded after HLA-DPB1*04 (DP04)-binding NY-ESO-1157-170 peptide vaccination in patients with ovarian cancer. Although both subsets recognized exogenous NY-ESO-1 protein pulsed on DP04(+) target cells, only one type recognized target cells with intracellular expression of NY-ESO-1. The tumor-recognizing CD4(+) T cells more efficiently recognized the short 8-9-mer peptides than the non-tumor-recognizing CD4(+) T cells. In addition to endosomal/lysosomal proteases that are typically involved in MHC-II antigen presentation, several pathways in the MHC class I presentation pathways, such as the proteasomal degradation and transporter-associated with antigen-processing-mediated peptide transport, were also involved in the presentation of intracellular NY-ESO-1 on MHC-II. The presentation was inhibited significantly by primaquine, a small molecule that inhibits endosomal recycling, consistent with findings that pharmacologic inhibition of new protein synthesis enhances antigen presentation. Together, our data demonstrate that cancer cells selectively present peptides from intracellular tumor antigens on MHC-II by multiple nonclassical antigen-processing pathways. Harnessing the direct tumor-recognizing ability of CD4(+) T cells could be a promising strategy to enhance antitumor immune responses in the immunosuppressive tumor microenvironment.

  19. Merkel cell polyomavirus large T antigen has growth-promoting and inhibitory activities.

    Science.gov (United States)

    Cheng, Jingwei; Rozenblatt-Rosen, Orit; Paulson, Kelly G; Nghiem, Paul; DeCaprio, James A

    2013-06-01

    Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer. In at least 80% of all MCC, Merkel cell polyomavirus (MCPyV) DNA has undergone clonal integration into the host cell genome, and most tumors express the MCPyV large and small T antigens. In all cases of MCC reported to date, the integrated MCPyV genome has undergone mutations in the large T antigen. These mutations result in expression of a truncated large T antigen that retains the Rb binding or LXCXE motif but deletes the DNA binding and helicase domains. However, the transforming functions of full-length and truncated MCPyV large T antigen are unknown. We compared the transforming activities of full-length, truncated, and alternatively spliced 57kT forms of MCPyV large T antigen. MCPyV large T antigen could bind to Rb but was unable to bind to p53. Furthermore, MCPyV-truncated large T antigen was more effective than full-length and 57kT large T antigen in promoting the growth of human and mouse fibroblasts. In contrast, expression of the MCPyV large T antigen C-terminal 100 residues could inhibit the growth of several different cell types. These data imply that the deletion of the C terminus of MCPyV large T antigen found in MCC serves not only to disrupt viral replication but also results in the loss of a distinct growth-inhibitory function intrinsic to this region. PMID:23514892

  20. Biochemical basis of synergy between antigen and T-helper (Th) cell-mediated activation of resting human B cells.

    OpenAIRE

    Chartash, E K; Crow, M K; Friedman, S M

    1989-01-01

    We have utilized CD23 expression as a marker for B cell activation in order to investigate the biochemical basis for synergy between antigen and T helper (Th) cells in the activation of resting human B cells. Our results confirm that while ligation of surface immunoglobulin (sIg) receptors by antigen analogues (e.g., F(ab')2 goat anti-human IgM) does not lead to CD23 expression, this stimulus markedly enhances CD23 expression induced during antigen specific Th-B cell interaction or by rIL-4. ...

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

    Science.gov (United States)

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

    2014-03-01

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

  2. 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...

  3. Proliferating cell nuclear antigen and Ki-67 immunohistochemistry of oligodendrogliomas with special reference to prognosis

    DEFF Research Database (Denmark)

    HEEGAARD, S.; Sommer, Helle Mølgaard; BROHOLM, H.;

    1995-01-01

    Background. The biologic behavior of oligodendrogliomas is somewhat unpredictable. A supplementary prognostic factor is, therefore, desirable. Methods. Thirty-two pure supratentorial oligodendrogliomas were investigated using proliferating cell nuclear antigen (PCNA) and Ki-67 immunohistochemical...

  4. Antigen selection in B-cell lymphomas--tracing the evidence.

    Science.gov (United States)

    Sutton, Lesley-Ann; Agathangelidis, Andreas; Belessi, Chrysoula; Darzentas, Nikos; Davi, Frederic; Ghia, Paolo; Rosenquist, Richard; Stamatopoulos, Kostas

    2013-12-01

    While signaling through the B cell receptor (BcR) facilitates B cell development and maintenance, it also carries intertwined risks for the development of lymphomas since malignant B cells can exploit these pathways in order to trigger and fuel clonal expansion. This corruption of the normal B cell response to antigens, leading to sustained BcR signaling, has given great impulse to investigate in detail the role of antigen in lymphomas. Suffice it to conclude from such studies, largely immunogenetics based, that the evidence implicating antigens (exogenous or self) in lymphoma development is substantial and that lymphomagenesis is functionally driven and dynamic, rather than a simple stochastic process. As the paradigm of antigen-driven lymphoma evolves, further investigation will be paramount to the identification of the inciting agent(s) that may be responsible for immunoproliferative neoplasms and also for the development of therapeutic agents targeting effectors of the BcR signaling pathway.

  5. Uptake and presentation of myelin basic protein by normal human B cells.

    Directory of Open Access Journals (Sweden)

    Marie Klinge Brimnes

    Full Text Available B cells may play both pathogenic and protective roles in T-cell mediated autoimmune diseases such as multiple sclerosis (MS. These functions relate to the ability of B cells to bind and present antigens. Under serum-free conditions we observed that 3-4% of circulating B cells from healthy donors were capable of binding the MS-associated self-antigen myelin basic protein (MBP and of presenting the immunodominant peptide MBP85-99, as determined by staining with the mAb MK16 recognising the peptide presented by HLA-DR15-positive cells. In the presence of serum, however, the majority of B cells bound MBP in a complement-dependent manner, and almost half of the B cells became engaged in presentation of MBP85-99. Even though complement receptor 1 (CR1, CD35 and CR2 (CD21 both contributed to binding of MBP to B cells, only CR2 was important for the subsequent presentation of MBP85-99. A high proportion of MBP85-99 presenting B cells expressed CD27, and showed increased expression of CD86 compared to non-presenting B cells. MBP-pulsed B cells induced a low frequency of IL-10-producing CD4+ T cells in 3 out of 6 donors, indicating an immunoregulatory role of B cells presenting MBP-derived peptides. The mechanisms described here refute the general assumption that B-cell presentation of self-antigens requires uptake via specific B-cell receptors, and may be important for maintenance of tolerance as well as for driving T-cell responses in autoimmune diseases.

  6. Tumor Expression of the Carcinoembryonic Antigen Correlates with High Mitotic Activity and Cell Pleomorphism Index in Lung Carcinoma

    Directory of Open Access Journals (Sweden)

    Rancés Blanco

    2013-01-01

    Full Text Available At present, some research efforts are focusing on the evaluation of a variety of tumor associated antigens (TAAs for a better understanding of tumor biology and genetics of lung tumors. For this reason, we evaluated the tissue expression of carcinoembryonic antigen (CEA and ior C2 (a cell surface O-linked glycoprotein carbohydrate chain TAA in lung carcinomas, as well as its correlation with a variety of clinicopathological features. The tissue expression of CEA was evidenced in 22/43 (51.16% lung carcinomas and it was correlated with mitotic activity, cell pleomorphism indexes, and age of patients. The expression of ior C2 was observed in 15/43 (34.88% tumors but no correlation with the clinicopathological features mentioned above was obtained. No correlation between both CEA and ior C2 antigens expression and the overall survival (OS of non-small-cell lung cancer patients was also observed. However, CEA-negative patients displayed higher OS rates as compared with positive ones (69.74 versus 58.26 months. Our results seem to be in agreement with the role of CEA expression in tumor cell proliferation, inhibition of cell polarizations and tissue architecture distortion. The significance of ior C2 antigen in these malignancies and it potential use in diagnosis, prognosis, and/or immunotherapy must be reevaluated.

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

    Directory of Open Access Journals (Sweden)

    Daniel S Chen

    2005-10-01

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

  8. Tandem CAR T cells targeting HER2 and IL13Rα2 mitigate tumor antigen escape.

    Science.gov (United States)

    Hegde, Meenakshi; Mukherjee, Malini; Grada, Zakaria; Pignata, Antonella; Landi, Daniel; Navai, Shoba A; Wakefield, Amanda; Fousek, Kristen; Bielamowicz, Kevin; Chow, Kevin K H; Brawley, Vita S; Byrd, Tiara T; Krebs, Simone; Gottschalk, Stephen; Wels, Winfried S; Baker, Matthew L; Dotti, Gianpietro; Mamonkin, Maksim; Brenner, Malcolm K; Orange, Jordan S; Ahmed, Nabil

    2016-08-01

    In preclinical models of glioblastoma, antigen escape variants can lead to tumor recurrence after treatment with CAR T cells that are redirected to single tumor antigens. Given the heterogeneous expression of antigens on glioblastomas, we hypothesized that a bispecific CAR molecule would mitigate antigen escape and improve the antitumor activity of T cells. Here, we created a CAR that joins a HER2-binding scFv and an IL13Rα2-binding IL-13 mutein to make a tandem CAR exodomain (TanCAR) and a CD28.ζ endodomain. We determined that patient TanCAR T cells showed distinct binding to HER2 or IL13Rα2 and had the capability to lyse autologous glioblastoma. TanCAR T cells exhibited activation dynamics that were comparable to those of single CAR T cells upon encounter of HER2 or IL13Rα2. We observed that TanCARs engaged HER2 and IL13Rα2 simultaneously by inducing HER2-IL13Rα2 heterodimers, which promoted superadditive T cell activation when both antigens were encountered concurrently. TanCAR T cell activity was more sustained but not more exhaustible than that of T cells that coexpressed a HER2 CAR and an IL13Rα2 CAR, T cells with a unispecific CAR, or a pooled product. In a murine glioblastoma model, TanCAR T cells mitigated antigen escape, displayed enhanced antitumor efficacy, and improved animal survival. Thus, TanCAR T cells show therapeutic potential to improve glioblastoma control by coengaging HER2 and IL13Rα2 in an augmented, bivalent immune synapse that enhances T cell functionality and reduces antigen escape.

  9. Tandem CAR T cells targeting HER2 and IL13Rα2 mitigate tumor antigen escape.

    Science.gov (United States)

    Hegde, Meenakshi; Mukherjee, Malini; Grada, Zakaria; Pignata, Antonella; Landi, Daniel; Navai, Shoba A; Wakefield, Amanda; Fousek, Kristen; Bielamowicz, Kevin; Chow, Kevin K H; Brawley, Vita S; Byrd, Tiara T; Krebs, Simone; Gottschalk, Stephen; Wels, Winfried S; Baker, Matthew L; Dotti, Gianpietro; Mamonkin, Maksim; Brenner, Malcolm K; Orange, Jordan S; Ahmed, Nabil

    2016-08-01

    In preclinical models of glioblastoma, antigen escape variants can lead to tumor recurrence after treatment with CAR T cells that are redirected to single tumor antigens. Given the heterogeneous expression of antigens on glioblastomas, we hypothesized that a bispecific CAR molecule would mitigate antigen escape and improve the antitumor activity of T cells. Here, we created a CAR that joins a HER2-binding scFv and an IL13Rα2-binding IL-13 mutein to make a tandem CAR exodomain (TanCAR) and a CD28.ζ endodomain. We determined that patient TanCAR T cells showed distinct binding to HER2 or IL13Rα2 and had the capability to lyse autologous glioblastoma. TanCAR T cells exhibited activation dynamics that were comparable to those of single CAR T cells upon encounter of HER2 or IL13Rα2. We observed that TanCARs engaged HER2 and IL13Rα2 simultaneously by inducing HER2-IL13Rα2 heterodimers, which promoted superadditive T cell activation when both antigens were encountered concurrently. TanCAR T cell activity was more sustained but not more exhaustible than that of T cells that coexpressed a HER2 CAR and an IL13Rα2 CAR, T cells with a unispecific CAR, or a pooled product. In a murine glioblastoma model, TanCAR T cells mitigated antigen escape, displayed enhanced antitumor efficacy, and improved animal survival. Thus, TanCAR T cells show therapeutic potential to improve glioblastoma control by coengaging HER2 and IL13Rα2 in an augmented, bivalent immune synapse that enhances T cell functionality and reduces antigen escape. PMID:27427982

  10. Location of T cell and major histocompatibility complex antigens in the human thymus

    OpenAIRE

    1980-01-01

    A series of monoclonal antibodies were used to study the intrathymic distribution of T cell-specific antigens, Ia antigens, and beta 2- microglobulin in frozen sections of human thymus by immunofluorescence and immunoperoxidase techniques. Most of the cortical thymocytes reacted with anti-T4, anti-T5, anti-T6, anti-T8, and anti-T10 antibodies, thus indicating coexpression of multiple antigens on cortical lymphocytes. The staining of cells in the medulla was most satisfactorily judged in secti...

  11. Involvement of proliferating cell nuclear antigen (cyclin) in DNA replication in living cells.

    OpenAIRE

    Zuber, M; Tan, E M; Ryoji, M

    1989-01-01

    Proliferating cell nuclear antigen (PCNA) (also called cyclin) is known to stimulate the activity of DNA polymerase delta but not the other DNA polymerases in vitro. We injected a human autoimmune antibody against PCNA into unfertilized eggs of Xenopus laevis and examined the effects of this antibody on the replication of injected plasmid DNA as well as egg chromosomes. The anti-PCNA antibody inhibited plasmid replication by up to 67%, demonstrating that PCNA is involved in plasmid replicatio...

  12. SERUM ANTIBODIES TO WHOLE-CELL AND RECOMBINANT ANTIGENS OF BORRELIA BURGDORFERI IN COTTONTAIL RABBITS

    OpenAIRE

    Magnarelli, Louis A.; Norris, Steven J; Fikrig, Erol

    2012-01-01

    Archived serum samples, from 95 eastern cottontail rabbits (Sylvilagus floridanus) captured in New York, New York, USA and Millbrook, New York, USA, during 1985–86, were analyzed in solid-phase enzyme-linked immunosorbent assays (ELISA) for total and class-specific immunoglobulin (Ig) M antibodies to whole-cell or recombinant antigens of Borrelia burgdorferi sensu stricto. Using a polyvalent conjugate, rabbit sera contained antibodies to whole-cell and recombinant antigens (protein [p]35, p37...

  13. Identification of chimeric antigen receptors that mediate constitutive or inducible proliferation of T cells

    OpenAIRE

    Frigault, Matthew J.; Lee, Jihyun; Basil, Maria Ciocca; Carpenito, Carmine; Motohashi, Shinichiro; Scholler, John; Kawalekar, Omkar U.; Guedan, Sonia; McGettigan, Shannon E; Posey, Avery D; Ang, Sonny; Cooper, Laurence J. N.; Platt, Jesse M.; Johnson, F. Brad; Paulos, Chrystal M.

    2015-01-01

    This study compared second generation chimeric antigen receptors encoding signaling domains composed of CD28, ICOS and 4-1BB. Here we report that certain CARs endow T cells with the ability to undergo long-term autonomous proliferation. Transduction of primary human T-cell with lentiviral vectors encoding some of the CARs resulted in sustained proliferation for up to three months following a single stimulation through the TCR. Sustained numeric expansion was independent of cognate antigen and...

  14. Quantitative interrelations of Lewis antigens in normal mucosa and transitional cell bladder carcinomas.

    OpenAIRE

    Limas, C

    1991-01-01

    The factors regulating the expression of the Lewis blood group related antigens in tissues have yet to be clarified. In an attempt to resolve some of the existing controversies the quantitative interrelationship of the Le(a), Le(b), X and Y antigens in normal urothelium and transitional cell carcinomas (TCC) was studied using biopsy specimens derived from 22 patients whose ABO and Lewis red blood cell phenotype was known. A quantitative scale was devised to encompass both the extent and inten...

  15. Hybrid human immunodeficiency virus Gag particles as an antigen carrier system: induction of cytotoxic T-cell and humoral responses by a Gag:V3 fusion.

    OpenAIRE

    Griffiths, J C; Harris, S. J.; Layton, G T; Berrie, E L; French, T J; Burns, N R; Adams, S E; Kingsman, A J

    1993-01-01

    In attempts to increase the immunogenicity of recombinant antigens, a number of particulate antigen presentation systems have been developed. In this study, we used human immunodeficiency virus Gag particles as carriers for the human immunodeficiency virus envelope V3 region. Gag:V3 fusion proteins were expressed from baculovirus expression vectors; they migrated to the insect cell membrane and budded from the cells as hybrid particles. An immunization study carried out with rats showed that ...

  16. Proliferating cell nuclear antigen (PCNA expression in pituitary adenomas: relationship to the endocrine phenotype of adenoma.

    Directory of Open Access Journals (Sweden)

    Andrzej Radek

    2006-04-01

    Full Text Available The expression of proliferating cell nuclear antigen (PCNA correlates to cell proliferation and for this reason it is commonly considered as one of proliferation markers. Since proliferation rate is an important factor determining the tumor aggressiveness, the evaluation of PCNA index (the percentage of PCNA-immunopositive nuclei in the investigated tumor sample is suggested as useful in predicting pituitary adenoma outcome. Seventy three unselected, surgically removed pituitary adenomas were immunostained with antibodies against the pituitary hormones or their subunits and against the proliferating cell nuclear antigen (PCNA. The highest PCNA index was found in ACTH-immunopositive tumors without the manifestation of the Cushing's disease ("silent" corticotropinomas. This value was significantly different in comparison to other adenoma subtypes including corticotropinomas manifesting themselves by Cushing's disease. The lowest PCNA index was noticed in monohormonal GH-secreting tumors. The adenomas which express more than one hormone (plurihormonal adenomas seem to have a higher PCNA indices than monohormonal ones; the difference was significant in the case of mono- and plurihormonal prolactinomas. The recurrent tumors presented a higher mean PCNA index as compared to the primary tumors, although the difference was significant only in the case of prolactinomas. These findings suggest that the proliferative potential of pituitary adenomas is related to the tumor recurrence and hormone expression.

  17. Immunophenotyping of Waldenstroms macroglobulinemia cell lines reveals distinct patterns of surface antigen expression: potential biological and therapeutic implications.

    Directory of Open Access Journals (Sweden)

    Aneel Paulus

    Full Text Available Waldenströms macroglobulinemia (WM is a subtype of Non-Hodgkin's lymphoma in which the tumor cell population is markedly heterogeneous, consisting of immunoglobulin-M secreting B-lymphocytes, plasmacytoid lymphocytes and plasma cells. Due to rarity of disease and scarcity of reliable preclinical models, many facets of WM molecular and phenotypic architecture remain incompletely understood. Currently, there are 3 human WM cell lines that are routinely used in experimental studies, namely, BCWM.1, MWCL-1 and RPCI-WM1. During establishment of RPCI-WM1, we observed loss of the CD19 and CD20 antigens, which are typically present on WM cells. Intrigued by this observation and in an effort to better define the immunophenotypic makeup of this cell line, we conducted a more comprehensive analysis for the presence or absence of other cell surface antigens that are present on the RPCI-WM1 model, as well as those on the two other WM cell lines, BCWM.1 and MWCL-1. We examined expression of 65 extracellular and 4 intracellular antigens, comprising B-cell, plasma cell, T-cell, NK-cell, myeloid and hematopoietic stem cell surface markers by flow cytometry analysis. RPCI-WM1 cells demonstrated decreased expression of CD19, CD20, and CD23 with enhanced expression of CD28, CD38 and CD184, antigens that were differentially expressed on BCWM.1 and MWCL-1 cells. Due to increased expression of CD184/CXCR4 and CD38, RPCI-WM1 represents a valuable model in which to study the effects anti-CXCR4 or anti-CD38 targeted therapies that are actively being developed for treatment of hematologic cancers. Overall, differences in surface antigen expression across the 3 cell lines may reflect the tumor clone population predominant in the index patients, from whom the cell lines were developed. Our analysis defines the utility of the most commonly employed WM cell lines as based on their immunophenotype profiles, highlighting unique differences that can be further studied for

  18. Combinational targeting offsets antigen escape and enhances effector functions of adoptively transferred T cells in glioblastoma.

    Science.gov (United States)

    Hegde, Meenakshi; Corder, Amanda; Chow, Kevin K H; Mukherjee, Malini; Ashoori, Aidin; Kew, Yvonne; Zhang, Yi Jonathan; Baskin, David S; Merchant, Fatima A; Brawley, Vita S; Byrd, Tiara T; Krebs, Simone; Wu, Meng Fen; Liu, Hao; Heslop, Helen E; Gottschalk, Stephen; Gottachalk, Stephen; Yvon, Eric; Ahmed, Nabil

    2013-11-01

    Preclinical and early clinical studies have demonstrated that chimeric antigen receptor (CAR)-redirected T cells are highly promising in cancer therapy. We observed that targeting HER2 in a glioblastoma (GBM) cell line results in the emergence of HER2-null tumor cells that maintain the expression of nontargeted tumor-associated antigens. Combinational targeting of these tumor-associated antigens could therefore offset this escape mechanism. We studied the single-cell coexpression patterns of HER2, IL-13Rα2, and EphA2 in primary GBM samples using multicolor flow cytometry and immunofluorescence, and applied a binomial routine to the permutations of antigen expression and the related odds of complete tumor elimination. This mathematical model demonstrated that cotargeting HER2 and IL-13Rα2 could maximally expand the therapeutic reach of the T cell product in all primary tumors studied. Targeting a third antigen did not predict an added advantage in the tumor cohort studied. We therefore generated bispecific T cell products from healthy donors and from GBM patients by pooling T cells individually expressing HER2 and IL-13Rα2-specific CARs and by making individual T cells to coexpress both molecules. Both HER2/IL-13Rα2-bispecific T cell products offset antigen escape, producing enhanced effector activity in vitro immunoassays (against autologous glioma cells in the case of GBM patient products) and in an orthotopic xenogeneic murine model. Further, T cells coexpressing HER2 and IL-13Rα2-CARs exhibited accentuated yet antigen-dependent downstream signaling and a particularly enhanced antitumor activity.

  19. 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

  20. Chimeric Antigen Receptor Therapy for B-cell Malignancies

    Directory of Open Access Journals (Sweden)

    David L Porter, Michael Kalos, Zhaohui Zheng, Bruce Levine, Carl June

    2011-01-01

    Full Text Available We presented data showing that the CART-19 cells expressing the 4-1BB signaling domain can have unprecedented and massive in-vivo expansion, traffic to tumor sites, persist long term in vivo, and induce rapid and potent anti-tumor activity in chemotherapy refractory CLL patients.

  1. Chimeric Antigen Receptor Therapy for B-cell Malignancies

    OpenAIRE

    Porter, David L.; Kalos, Michael; Zheng, Zhaohui; Levine, Bruce; June, Carl

    2011-01-01

    We presented data showing that the CART-19 cells expressing the 4-1BB signaling domain can have unprecedented and massive in-vivo expansion, traffic to tumor sites, persist long term in vivo, and induce rapid and potent anti-tumor activity in chemotherapy refractory CLL patients.

  2. Secretion, interaction and assembly of two O-glycosylated cell wall antigens from Candida albicans.

    Science.gov (United States)

    Pavia, J; Aguado, C; Mormeneo, S; Sentandreu, R

    2001-07-01

    The mechanisms of incorporation of two antigens have been determined using a monoclonal antibody (3A10) raised against the material released from the mycelial cell wall by zymolyase digestion and retained on a concanavalin A column. One of the hybridomas secreted an IgG that reacted with two bands in Western blots. Indirect immunofluorescence showed that the antigens were located on the surfaces of mycelial cells, but within the cell walls of yeasts. These antigens were detected in a membrane preparation, in the SDS-soluble material and in the material released by a 1,3-beta-glucanase and chitinase from the cell walls of yeast and mycelial cells. In the latter three samples, an additional high-molecular-mass, highly polydispersed band was also detected. Beta-elimination of each fraction resulted in the disappearance of all antigen bands, suggesting that they are highly O-glycosylated. In addition, the electrophoretic mobility of the high-molecular-mass, highly polydispersed bands increased after digestion with endoglycosidase H, indicating that they are also N-glycosylated. New antigen bands were released when remnants of the cell walls extracted with 1,3-beta-glucanase or chitinase were digested with chitinase or 1,3-beta-glucanase. These results are consistent with the notion that, after secretion, parts of the O-glycosylated antigen molecules are transferred to an N-glycosylated protein(s). This molecular complex, as well as the remaining original 70 and 80 kDa antigen molecules, next bind to 1,3-beta-glucan or chitin, probably via 1,6-beta-glucan, and, in an additional step, to chitin or 1,3-beta-glucan. This process results in the final molecular product of each antigen, and their distribution in the cell walls. PMID:11429475

  3. Cytotoxicity of tumor antigen specific human T cells is unimpaired by arginine depletion.

    Directory of Open Access Journals (Sweden)

    Markus Munder

    Full Text Available Tumor-growth is often associated with the expansion of myeloid derived suppressor cells that lead to local or systemic arginine depletion via the enzyme arginase. It is generally assumed that this arginine deficiency induces a global shut-down of T cell activation with ensuing tumor immune escape. While the impact of arginine depletion on polyclonal T cell proliferation and cytokine secretion is well documented, its influence on chemotaxis, cytotoxicity and antigen specific activation of human T cells has not been demonstrated so far. We show here that chemotaxis and early calcium signaling of human T cells are unimpaired in the absence of arginine. We then analyzed CD8(+ T cell activation in a tumor peptide as well as a viral peptide antigen specific system: (i CD8(+ T cells with specificity against the MART-1aa26-35*A27L tumor antigen expanded with in vitro generated dendritic cells, and (ii clonal CMV pp65aa495-503 specific T cells and T cells retrovirally transduced with a CMV pp65aa495-503 specific T cell receptor were analyzed. Our data demonstrate that human CD8(+ T cell antigen specific cytotoxicity and perforin secretion are completely preserved in the absence of arginine, while antigen specific proliferation as well as IFN-γ and granzyme B secretion are severely compromised. These novel results highlight the complexity of antigen specific T cell activation and demonstrate that human T cells can preserve important activation-induced effector functions in the context of arginine deficiency.

  4. Successive Administration of Streptococcus Type 5 Group A Antigens and S. typhimurium Antigenic Complex Corrects Elevation of Serum Cytokine Concentration and Number of Bone Marrow Stromal Pluripotent Cells in CBA Mice Induced by Each Antigen Separately.

    Science.gov (United States)

    Gorskaya, Yu F; Danilova, T A; Grabko, V I; Nesterenko, V G

    2015-12-01

    Administration of bacterial antigens to CBA mice induced an increase in serum concentration of virtually all cytokines with a peak in 4 h after administration of S. typhimurium antigens and in 7 h after administration of streptococcus antigens. In 20 h, cytokine concentrations returned to the control level or were slightly below it. In 4 h after administration of S. typhimurium antigens preceded 3 h before by administration of streptococcus antigens, we observed a significant decrease in serum concentrations of IFN-γ, IL-10, GM-CSF, IL-12, and TNF-α, in comparison with injection S. typhimurium antigens alone and IL-5, IL-10, GM-CSF, and TNF-α in comparison with injection of streptococcus antigens alone; the concentrations of IL-2 and IFN-γ, in contrast, increased by 1.5 times in this case. In 20 h after administration of S. typhimurium antigens, the number of multipotential stromal cells (MSC) in the bone marrow and their cloning efficiency (ECF-MSC) increased by 4.8 and 4.4 times, respectively, in comparison with the control, while after administration of streptococcus antigens by 2.6 and 2.4 times, respectively. In 20 h after administration of S. typhimurium antigens preceded 3 h before by administration of streptococcus antigens, these parameters increased by 3.2 and 2.9 times, respectively, in comparison with the control, i.e. the observed increase in the level of MSC count and ECF-MSC is more consistent with the response of the stromal tissue to streptococcus antigens. Thus, successive administration of two bacterial antigens corrected both serum cytokine profiles and MSC response to administration of each antigen separately, which indicates changeability of the stromal tissue in response to changes in the immune response.

  5. Neural Crest Cells Isolated from the Bone Marrow of Transgenic Mice Express JCV T-Antigen.

    Directory of Open Access Journals (Sweden)

    Jennifer Gordon

    Full Text Available JC virus (JCV, a common human polyomavirus, is the etiological agent of the demyelinating disease, progressive multifocal leukoencephalopathy (PML. In addition to its role in PML, studies have demonstrated the transforming ability of the JCV early protein, T-antigen, and its association with some human cancers. JCV infection occurs in childhood and latent virus is thought to be maintained within the bone marrow, which harbors cells of hematopoietic and non-hematopoietic lineages. Here we show that non-hematopoietic mesenchymal stem cells (MSCs isolated from the bone marrow of JCV T-antigen transgenic mice give rise to JCV T-antigen positive cells when cultured under neural conditions. JCV T-antigen positive cells exhibited neural crest characteristics and demonstrated p75, SOX-10 and nestin positivity. When cultured in conditions typical for mesenchymal cells, a population of T-antigen negative cells, which did not express neural crest markers arose from the MSCs. JCV T-antigen positive cells could be cultured long-term while maintaining their neural crest characteristics. When these cells were induced to differentiate into neural crest derivatives, JCV T-antigen was downregulated in cells differentiating into bone and maintained in glial cells expressing GFAP and S100. We conclude that JCV T-antigen can be stably expressed within a fraction of bone marrow cells differentiating along the neural crest/glial lineage when cultured in vitro. These findings identify a cell population within the bone marrow permissible for JCV early gene expression suggesting the possibility that these cells could support persistent viral infection and thus provide clues toward understanding the role of the bone marrow in JCV latency and reactivation. Further, our data provides an excellent experimental model system for studying the cell-type specificity of JCV T-antigen expression, the role of bone marrow-derived stem cells in the pathogenesis of JCV-related diseases

  6. The generation and antigen-specificity of CD4+CD25+ regulatory T cells.

    Science.gov (United States)

    Taams, Leonie S; Curnow, S John; Vukmanovic-Stejic, M; Akbar, Arne N

    2006-09-01

    CD4+CD25+ regulatory T cells are essential components of the immune system. They help to maintain immune tolerance by exerting suppressive effects on cells of the adaptive and innate immune system. In the last few years there has been an abundance of papers addressing the suppressive effects of CD4+CD25+ regulatory T cells and their putative role in various experimental disease models and human diseases. Despite the enormous amounts of data on these cells a number of controversial issues still exists. CD4+CD25+ regulatory T cells were originally described as thymus-derived anergic/suppressive T cells. Recent papers however indicate that these cells might also be generated in the periphery. Due to the thymic development of CD4+CD25+ regulatory T cells it was thought that these cells were specific for self-antigens. Indeed it was shown that CD4+CD25+ regulatory T cells could be positively selected upon high affinity interaction with self-antigens. However, evidence is accumulating that these cells might also interact with non-self antigens. Finally, in the literature there is conflicting evidence regarding the role of soluble factors versus cell-contact in the mechanism of suppression. The aim of this review is to summarize the evidence supporting these opposing viewpoints and to combine them into a general model for the origin, function and antigen-specificity of CD4+CD25+ regulatory T cells. PMID:16918478

  7. Detection and manipulation of live antigen-expressing cells using conditionally stable nanobodies.

    Science.gov (United States)

    Tang, Jonathan Cy; Drokhlyansky, Eugene; Etemad, Behzad; Rudolph, Stephanie; Guo, Binggege; Wang, Sui; Ellis, Emily G; Li, Jonathan Z; Cepko, Constance L

    2016-01-01

    The ability to detect and/or manipulate specific cell populations based upon the presence of intracellular protein epitopes would enable many types of studies and applications. Protein binders such as nanobodies (Nbs) can target untagged proteins (antigens) in the intracellular environment. However, genetically expressed protein binders are stable regardless of antigen expression, complicating their use for applications that require cell-specificity. Here, we created a conditional system in which the stability of an Nb depends upon an antigen of interest. We identified Nb framework mutations that can be used to rapidly create destabilized Nbs. Fusion of destabilized Nbs to various proteins enabled applications in living cells, such as optogenetic control of neural activity in specific cell types in the mouse brain, and detection of HIV-infected human cells by flow cytometry. These approaches are generalizable to other protein binders, and enable the rapid generation of single-polypeptide sensors and effectors active in cells expressing specific intracellular epitopes. PMID:27205882

  8. 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

  9. Vitamin D controls T cell antigen receptor signaling and activation of human T cells

    DEFF Research Database (Denmark)

    von Essen, Marina Rode; Kongsbak-Wismann, Martin; Schjerling, Peter;

    2010-01-01

    Phospholipase C (PLC) isozymes are key signaling proteins downstream of many extracellular stimuli. Here we show that naive human T cells had very low expression of PLC-gamma1 and that this correlated with low T cell antigen receptor (TCR) responsiveness in naive T cells. However, TCR triggering...... led to an upregulation of approximately 75-fold in PLC-gamma1 expression, which correlated with greater TCR responsiveness. Induction of PLC-gamma1 was dependent on vitamin D and expression of the vitamin D receptor (VDR). Naive T cells did not express VDR, but VDR expression was induced by TCR...... signaling via the alternative mitogen-activated protein kinase p38 pathway. Thus, initial TCR signaling via p38 leads to successive induction of VDR and PLC-gamma1, which are required for subsequent classical TCR signaling and T cell activation....

  10. The administration route is decisive for the ability of the vaccine adjuvant CAF09 to induce antigen-specific CD8(+) T-cell responses

    DEFF Research Database (Denmark)

    Schmidt, Signe Tandrup; Khadke, Swapnil; Korsholm, Karen Smith;

    2016-01-01

    A prerequisite for vaccine-mediated induction of CD8(+) T-cell responses is the targeting of dendritic cell (DC) subsets specifically capable of cross-presenting antigen epitopes to CD8(+) T cells. Administration of a number of cationic adjuvants via the intraperitoneal (i.p.) route has been show...

  11. Inhibition of Ly-6A antigen expression prevents T cell activation

    OpenAIRE

    1990-01-01

    Antisense oligonucleotides complementary to the 5' end of the mRNA encoding the Ly-6A protein were used to block the expression of that protein. Using this approach we could inhibit the expression of Ly-6A by 60-80% in antigen-primed lymph node (LN) T cells as well as in the D10 T cell clone. Inhibition of Ly-6 expression resulted in the inability to restimulate in vitro, antigen-primed T cells. It also blocked the activation of normal spleen cells by Con A, monoclonal antibody (mAb) to CD3, ...

  12. Low antigenicity of hematopoietic progenitor cells derived from human ES cells

    Directory of Open Access Journals (Sweden)

    Eun-Mi Kim

    2010-02-01

    Full Text Available Eun-Mi Kim1, Nicholas Zavazava1,21Department of Internal Medicine, University of Iowa and Veterans Affairs Medical Center, Iowa City, Iowa, USA; 2Immunology Graduate Program, University of Iowa, Iowa City, Iowa, USAAbstract: Human embryonic stem (hES cells are essential for improved understanding of diseases and our ability to probe new therapies for use in humans. Currently, bone marrow cells and cord blood cells are used for transplantation into patients with hematopoietic malignancies, immunodeficiencies and in some cases for the treatment of autoimmune diseases. However, due to the high immunogenicity of these hematopoietic cells, toxic regimens of drugs are required for preconditioning and prevention of rejection. Here, we investigated the efficiency of deriving hematopoietic progenitor cells (HPCs from the hES cell line H13, after co-culturing with the murine stromal cell line OP9. We show that HPCs derived from the H13 ES cells poorly express major histocompatibility complex (MHC class I and no detectable class II antigens (HLA-DR. These characteristics make hES cell-derived hematopoietic cells (HPCs ideal candidates for transplantation across MHC barriers under minimal immunosuppression.Keywords: human embryonic stem cells, H13, hematopoiesis, OP9 stromal cells, immunogenicity

  13. Flow Cytometric Analysis of T, B, and NK Cells Antigens in Patients with Mycosis Fungoides

    Directory of Open Access Journals (Sweden)

    Serkan Yazıcı

    2015-01-01

    Full Text Available We retrospectively analyzed the clinicopathological correlation and prognostic value of cell surface antigens expressed by peripheral blood mononuclear cells in patients with mycosis fungoides (MF. 121 consecutive MF patients were included in this study. All patients had peripheral blood flow cytometry as part of their first visit. TNMB and histopathological staging of the cases were retrospectively performed in accordance with International Society for Cutaneous Lymphomas/European Organization of Research and Treatment of Cancer (ISCL/EORTC criteria at the time of flow cytometry sampling. To determine prognostic value of cell surface antigens, cases were divided into two groups as stable and progressive disease. 17 flow cytometric analyses of 17 parapsoriasis (PP and 11 analyses of 11 benign erythrodermic patients were included as control groups. Fluorescent labeled monoclonal antibodies were used to detect cell surface antigens: T cells (CD3+, CD4+, CD8+, TCRαβ+, TCRγδ+, CD7+, CD4+CD7+, CD4+CD7−, and CD71+, B cells (HLA-DR+, CD19+, and HLA-DR+CD19+, NKT cells (CD3+CD16+CD56+, and NK cells (CD3−CD16+CD56+. The mean value of all cell surface antigens was not statistically significant between parapsoriasis and MF groups. Along with an increase in cases of MF stage statistically significant difference was found between the mean values of cell surface antigens. Flow cytometric analysis of peripheral blood cell surface antigens in patients with mycosis fungoides may contribute to predicting disease stage and progression.

  14. 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

  15. Purification and characterization of fetal hematopoietic cells that express the common acute lymphoblastic leukemia antigen (CALLA)

    DEFF Research Database (Denmark)

    Hokland, P; Rosenthal, P; Griffin, J D;

    1983-01-01

    Fetal hematopoietic cells that express the common acute lymphoblastic leukemia antigen (CALLA) were purified from both fetal liver and fetal bone marrow by immune rosetting with sheep erythrocytes coated with rabbit anti-mouse immunoglobulin and by fluorescence-activated cell sorting. Dual fluore...... that these cells are relatively immature lymphoid cells, CALLA+ cells do not appear to contain either myeloid precursor cells (CFU-G/M) or the earliest lymphoid stem cells. Udgivelsesdato: 1983-Jan-1......Fetal hematopoietic cells that express the common acute lymphoblastic leukemia antigen (CALLA) were purified from both fetal liver and fetal bone marrow by immune rosetting with sheep erythrocytes coated with rabbit anti-mouse immunoglobulin and by fluorescence-activated cell sorting. Dual...... fluorescence techniques disclosed that these cells were heterogenous with respect to the expression of a series of differentiation and activation antigens defined by monoclonal antibodies. Thus, whereas all CALLA+ cells were Ia+ and expressed two activation antigens, J2 and T10, only 30-50% expressed B1...

  16. Antigen-specific monoclonal antibodies isolated from B cells expressing constitutively active STAT5.

    Directory of Open Access Journals (Sweden)

    Ferenc A Scheeren

    Full Text Available BACKGROUND: Fully human monoclonal antibodies directed against specific pathogens have a high therapeutic potential, but are difficult to generate. METHODOLOGY/PRINCIPAL FINDINGS: Memory B cells were immortalized by expressing an inducible active mutant of the transcription factor Signal Transducer and Activator of Transcription 5 (STAT5. Active STAT5 inhibits the differentiation of B cells while increasing their replicative life span. We obtained cloned B cell lines, which produced antibodies in the presence of interleukin 21 after turning off STAT5. We used this method to obtain monoclonal antibodies against the model antigen tetanus toxin. CONCLUSIONS/SIGNIFICANCE: Here we describe a novel and relatively simple method of immortalizing antigen-specific human B cells for isolation of human monoclonal antibodies. These results show that STAT5 overexpression can be employed to isolate antigen specific antibodies from human memory B cells.

  17. Modified tumour antigen-encoding mRNA facilitates the analysis of naturally occurring and vaccine-induced CD4 and CD8 T cells in cancer patients.

    Science.gov (United States)

    Knights, Ashley J; Nuber, Natko; Thomson, Christopher W; de la Rosa, Olga; Jäger, Elke; Tiercy, Jean-Marie; van den Broek, Maries; Pascolo, Steve; Knuth, Alexander; Zippelius, Alfred

    2009-03-01

    The development of effective anti-cancer vaccines requires precise assessment of vaccine-induced immunity. This is often hampered by low ex vivo frequencies of antigen-specific T cells and limited defined epitopes. This study investigates the applicability of modified, in vitro-transcribed mRNA encoding a therapeutically relevant tumour antigen to analyse T cell responses in cancer patients. In this study transfection of antigen presenting cells, by mRNA encoding the tumour antigen NY-ESO-1, was optimised and applied to address spontaneous and vaccine-induced T cell responses in cancer patients. Memory CD8+ T cells from lung cancer patients having detectable humoral immune responses directed towards NY-ESO-1 could be efficiently detected in peripheral blood. Specific T cells utilised a range of different T cell receptors, indicating a polyclonal response. Specific killing of a panel of NY-ESO-1 expressing tumour cell lines indicates recognition restricted to several HLA allelic variants, including a novel HLA-B49 epitope. Using a modified mRNA construct targeting the translated antigen to the secretory pathway, detection of NY-ESO-1-specific CD4+ T cells in patients could be enhanced, which allowed the in-depth characterisation of established T cell clones. Moreover, broad CD8+ and CD4+ T cell responses covering multiple epitopes were detected following mRNA stimulation of patients treated with a recombinant vaccinia/fowlpox NY-ESO-1 vaccine. This approach allows for a precise monitoring of responses to tumour antigens in a setting that addresses the breadth and magnitude of antigen-specific T cell responses, and that is not limited to a particular combination of known epitopes and HLA-restrictions. PMID:18663444

  18. Human T cell responses to dengue virus antigens. Proliferative responses and interferon gamma production.

    OpenAIRE

    Kurane, I; Innis, B L; Nisalak, A; Hoke, C; Nimmannitya, S; Meager, A.; Ennis, F A

    1989-01-01

    The severe complications of dengue virus infections, hemorrhagic manifestations and shock, are more commonly observed during secondary dengue virus infections than during primary infections. It has been speculated that these complications are mediated by cross-reactive host-immune responses. We have begun to analyze human T cell responses to dengue antigens in vitro to explain the possible role of T lymphocytes in the pathogenesis of these complications. Dengue antigens induce proliferative r...

  19. Immunofluorescence of bovine virus diarrhea viral antigen in white blood cells from experimentally infected immunocompetent calves.

    OpenAIRE

    Bezek, D M; Baker, J. C.; Kaneene, J B

    1988-01-01

    A study to evaluate the detection of bovine virus diarrhea viral antigen using immunofluorescence testing of white blood cells was conducted. Five colostrum-deprived calves were inoculated intravenously with a cytopathic strain of the virus. Lymphocyte and buffy coat smears were prepared daily for direct immunofluorescent staining for detection of antigen. Lymphocytes were separated from heparinized blood using a Ficoll density procedure. Buffy coat smears were prepared from centrifuged blood...

  20. Degranulation of human mast cells induces an endothelial antigen central to leukocyte adhesion.

    OpenAIRE

    Klein, L M; Lavker, R M; Matis, W L; Murphy, G F

    1989-01-01

    To understand better the role of mast cell secretory products in the genesis of inflammation, a system was developed for in vitro degranulation of human mast cells in skin organ cultures. Within 2 hr after morphine sulfate-induced degranulation, endothelial cells lining microvessels adjacent to affected mast cells expressed an activation antigen important for endothelial-leukocyte adhesion. Identical results were obtained when other mast cell secretagogues (anti-IgE, compound 48/80, and calci...

  1. Enhanced interferon-γ secretion and antitumor activity of T-lymphocytes activated by dendritic cells loaded with glycoengineered myeloma antigens

    Institute of Scientific and Technical Information of China (English)

    XIONG Hong; WU Qiu-ye; HU Hong-gang; LIU Ban; GUO Zhong-wu; Daniel Man-yuan Sze; HOU Jian

    2007-01-01

    Background Immunotherapy is emerging as a promising cure for cancer. However, a severe problem in this area is the immune tolerance to tumor cells and tumor-associated antigens, as evidenced by the ability of cancer to escape immune surveillance. To overcome this problem this work examined the potential of improving the antigenicity of myeloma by metabolic engineering of its cell surface carbohydrate antigens (i.e., glycoengineering) and presentation of the modified tumor antigens by dendritic cells (DCs) to generate cytotoxic T-lymphocytes (CTLs).Methods CD138+ myeloma cells were isolated from 11 multipe myeloma (MM) patients by the immunomagnetic bead method. The MM cells were treated with N-propionyl-D-mannosamine (ManNPr), a synthetic analog of N-acetyl-D-mannosamine (ManNAc), the natural biosynthetic precursor of N-acetyl sialic acid (NeuNAc), to express unnatural N-propionylated sialoglycans. The giycoengineered cells were then induced to apoptosis, and the apoptotic products were added to cultured functional DCs that could present the unnatural carbohydrate antigens to autologous T-lymphocytes.Results It was found that the resultant DCs could activate CD4+ and CD8+ T-lymphocytes, resulting in increased expression of T cell surface markers, including CD8CD28 and CD4CD29. Moreover, upon stimulation by glycoengineered MM cells, these DC-activated T-lymphocytes could release significantly higher levels of IFN-γ (P<0.05).Lactate dehydrogenase (LDH) assays further showed that the stimulated T-lymphocytes were cytotoxic to glycoengineered MM cells.Conclusions This work demonstrated that glycoengineered myeloma cells were highly antigenic and the CTLs induced by the DCs loaded with the unnatural myeloma antigens were specifically cytotoxic to the glycoengineered myeloma.This may provide a new strategy for overcoming the problem of immune tolerance for the development of effective immunotherapies for MM.

  2. Past, present and future of fuel cells

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Though the fuel cell was invented by Grove in 1839,there are no commercially viable products at present.The development of fuel cells can be conveniently divided into three phases-exploratory phase(1839-1967).The main emphasis of the work is to increase the area of the three-phase interface at the electrode.The problem was solved by Bacon who invented the dual porosity,biporous nickel electrode.He demonstrated the first H2/O2 fuel cell(180℃,20atm).This cell was later improved and scaled up to power the Apollo lunar mission.However,the cost is too high for civilian applications and we come to the development phase (1967-2001).The main emphasis has been on the use of Teflon bonded electrodes and novel catalysts(PtRu,Pt/WO3 and Pt-Ru/WO3 anode catalyst for the anodic oxidation of impure H2 and methanol.In addition,the recent discovery of gadolinium doped ceria has reduced the operating temperature of solid oxide electrolytes to ~500℃ instead of 1 000℃.From 2001 onwards,we may be entering the breakthrough phase where the most favourable candidates are direct methanol vapor fuel cells and solid oxide electrolyte fuel cells.In the former case,there is a need to reduce the cross-over of methanol to the cathode compartment and the development of air cathode catalyst which are less affected by methanol and in the latter case,there is a need to improve the activity of the anode and cathode catalysts.

  3. Development of an algorithm for production of inactivated arbovirus antigens in cell culture.

    Science.gov (United States)

    Goodman, C H; Russell, B J; Velez, J O; Laven, J J; Nicholson, W L; Bagarozzi, D A; Moon, J L; Bedi, K; Johnson, B W

    2014-11-01

    Arboviruses are medically important pathogens that cause human disease ranging from a mild fever to encephalitis. Laboratory diagnosis is essential to differentiate arbovirus infections from other pathogens with similar clinical manifestations. The Arboviral Diseases Branch (ADB) reference laboratory at the CDC Division of Vector-Borne Diseases (DVBD) produces reference antigens used in serological assays such as the virus-specific immunoglobulin M antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA). Antigen production in cell culture has largely replaced the use of suckling mice; however, the methods are not directly transferable. The development of a cell culture antigen production algorithm for nine arboviruses from the three main arbovirus families, Flaviviridae, Togaviridae, and Bunyaviridae, is described here. Virus cell culture growth and harvest conditions were optimized, inactivation methods were evaluated, and concentration procedures were compared for each virus. Antigen performance was evaluated by the MAC-ELISA at each step of the procedure. The antigen production algorithm is a framework for standardization of methodology and quality control; however, a single antigen production protocol was not applicable to all arboviruses and needed to be optimized for each virus.

  4. Antigen dynamics govern the induction of CD4(+) T cell tolerance during autoimmunity.

    Science.gov (United States)

    Challa, Dilip K; Mi, Wentao; Lo, Su-Tang; Ober, Raimund J; Ward, E Sally

    2016-08-01

    Antigen-specific T cell tolerance holds great promise for the treatment of autoimmune diseases. However, strategies to induce durable tolerance using high doses of soluble antigen have to date been unsuccessful, due to lack of efficacy and the risk of hypersensitivity. In the current study we have overcome these limitations by developing a platform for tolerance induction based on engineering the immunoglobulin Fc region to modulate the dynamic properties of low doses (1 μg/mouse; ∼50 μg/kg) of Fc-antigen fusions. Using this approach, we demonstrate that antigen persistence is a dominant factor governing the elicitation of tolerance in the model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE), induced by immunizing B10.PL mice with the N-terminal epitope of myelin basic protein. Unexpectedly, our analyses reveal a stringent threshold of antigen persistence for both prophylactic and therapeutic treatments, although distinct mechanisms lead to tolerance in these two settings. Importantly, the delivery of tolerogenic Fc-antigen fusions during ongoing disease results in the downregulation of T-bet and CD40L combined with amplification of Foxp3(+) T cell numbers. The generation of effective, low dose tolerogens using Fc engineering has potential for the regulation of autoreactive T cells. PMID:27236506

  5. Leishmania chagasi T-cell antigens identified through a double library screen.

    Science.gov (United States)

    Martins, Daniella R A; Jeronimo, Selma M B; Donelson, John E; Wilson, Mary E

    2006-12-01

    Control of human visceral leishmaniasis in regions where it is endemic is hampered in part by limited accessibility to medical care and emerging drug resistance. There is no available protective vaccine. Leishmania spp. protozoa express multiple antigens recognized by the vertebrate immune system. Since there is not one immunodominant epitope recognized by most hosts, strategies must be developed to optimize selection of antigens for prevention and immunodiagnosis. For this reason, we generated a cDNA library from the intracellular amastigote form of Leishmania chagasi, the cause of South American visceral leishmaniasis. We employed a two-step expression screen of the library to systematically identify T-cell antigens and T-dependent B-cell antigens. The first step was aimed at identifying the largest possible number of clones producing an epitope-containing polypeptide by screening with a pool of sera from Brazilians with documented visceral leishmaniasis. After removal of clones encoding heat shock proteins, positive clones underwent a second-step screen for their ability to cause proliferation and gamma interferon responses in T cells from immune mice. Six unique clones were selected from the second screen for further analysis. The corresponding antigens were derived from glutamine synthetase, a transitional endoplasmic reticulum ATPase, elongation factor 1gamma, kinesin K39, repetitive protein A2, and a hypothetical conserved protein. Humans naturally infected with L. chagasi mounted both cellular and antibody responses to these proteins. Preparations containing multiple antigens may be optimal for immunodiagnosis and protective vaccines. PMID:17000724

  6. Self-antigen recognition by TGFβ1-deficient T cells causes their activation and systemic inflammation

    OpenAIRE

    Bommireddy, Ramireddy; Pathak, Leena J; Martin, Jennifer; Ormsby, Ilona; Engle, Sandra J; Gregory P. Boivin; Babcock, George F.; Eriksson, Anna U.; Singh, Ram R; DOETSCHMAN, THOMAS

    2006-01-01

    To investigate whether the multifocal inflammatory disease in TGFβ1-deficient mice is caused by self-antigen (self-Ag)-specific autoreactive T cells, or whether it is caused by antigen independent, spontaneous hyperactivation of T cells, we have generated Tgfb1−/− and Tgfb1−/− Rag1−/− mice expressing the chicken OVA-specific TCR transgene (DO11.10). On a Rag1-sufficient background, Tgfb1−/− DO11.10 mice develop a milder inflammation than do Tgfb1−/− mice, and their T cells display a less acti...

  7. Durable Complete Response from Metastatic Melanoma after Transfer of Autologous T Cells Recognizing 10 Mutated Tumor Antigens.

    Science.gov (United States)

    Prickett, Todd D; Crystal, Jessica S; Cohen, Cyrille J; Pasetto, Anna; Parkhurst, Maria R; Gartner, Jared J; Yao, Xin; Wang, Rong; Gros, Alena; Li, Yong F; El-Gamil, Mona; Trebska-McGowan, Kasia; Rosenberg, Steven A; Robbins, Paul F

    2016-08-01

    Immunotherapy treatment of patients with metastatic cancer has assumed a prominent role in the clinic. Durable complete response rates of 20% to 25% are achieved in patients with metastatic melanoma following adoptive cell transfer of T cells derived from metastatic lesions, responses that appear in some patients to be mediated by T cells that predominantly recognize mutated antigens. Here, we provide a detailed analysis of the reactivity of T cells administered to a patient with metastatic melanoma who exhibited a complete response for over 3 years after treatment. Over 4,000 nonsynonymous somatic mutations were identified by whole-exome sequence analysis of the patient's autologous normal and tumor cell DNA. Autologous B cells transfected with 720 mutated minigenes corresponding to the most highly expressed tumor cell transcripts were then analyzed for their ability to stimulate the administered T cells. Autologous tumor-infiltrating lymphocytes recognized 10 distinct mutated gene products, but not the corresponding wild-type products, each of which was recognized in the context of one of three different MHC class I restriction elements expressed by the patient. Detailed clonal analysis revealed that 9 of the top 20 most prevalent clones present in the infused T cells, comprising approximately 24% of the total cells, recognized mutated antigens. Thus, we have identified and enriched mutation-reactive T cells and suggest that such analyses may lead to the development of more effective therapies for the treatment of patients with metastatic cancer. Cancer Immunol Res; 4(8); 669-78. ©2016 AACR.

  8. TSCOT+ thymic epithelial cell-mediated sensitive CD4 tolerance by direct presentation.

    Directory of Open Access Journals (Sweden)

    Sejin Ahn

    2008-08-01

    Full Text Available Although much effort has been directed at dissecting the mechanisms of central tolerance, the role of thymic stromal cells remains elusive. In order to further characterize this event, we developed a mouse model restricting LacZ to thymic stromal cotransporter (TSCOT-expressing thymic stromal cells (TDLacZ. The thymus of this mouse contains approximately 4,300 TSCOT+ cells, each expressing several thousand molecules of the LacZ antigen. TSCOT+ cells express the cortical marker CDR1, CD40, CD80, CD54, and major histocompatibility complex class II (MHCII. When examining endogenous responses directed against LacZ, we observed significant tolerance. This was evidenced in a diverse T cell repertoire as measured by both a CD4 T cell proliferation assay and an antigen-specific antibody isotype analysis. This tolerance process was at least partially independent of Autoimmune Regulatory Element gene expression. When TDLacZ mice were crossed to a novel CD4 T cell receptor (TCR transgenic reactive against LacZ (BgII, there was a complete deletion of double-positive thymocytes. Fetal thymic reaggregate culture of CD45- and UEA-depleted thymic stromal cells from TDLacZ and sorted TCR-bearing thymocytes excluded the possibility of cross presentation by thymic dendritic cells and medullary epithelial cells for the deletion. Overall, these results demonstrate that the introduction of a neoantigen into TSCOT-expressing cells can efficiently establish complete tolerance and suggest a possible application for the deletion of antigen-specific T cells by antigen introduction into TSCOT+ cells.

  9. High Frequencies of Anti-Host Reactive CD8+ T Cells Ignore Non-Hematopoietic Antigen after Bone Marrow Transplantation in a Murine Model

    Directory of Open Access Journals (Sweden)

    Asmae Gassa

    2016-03-01

    Full Text Available Background: Graft versus host disease (GvHD occurs in 20% of cases with patients having an MHC I matched bone marrow transplantation (BMT. Mechanisms causing this disease remain to be studied. Methods: Here we used a CD8+ T cell transgenic mouse line (P14/CD45.1+ and transgenic DEE mice bearing ubiquitously the glycoprotein 33-41 (GP33 antigen derived from the major lymphocytic choriomeningitis virus (LCMV epitope to study mechanisms of tolerance in anti-host reactive CD8+ T cells after BMT. Results: We found that anti-host reactive CD8+ T cells (P14 T cells were not negatively selected in the thymus and that they were present in wild type (WT recipient mice as well as in DEE recipient mice. Anti-host reactive CD8+ T cells ignored the GP33 antigen expressed ubiquitously by host cells but they could be activated ex vivo via LCMV-infection. Lipopolysaccharides (LPS induced transient cell damage in DEE mice bearing anti-host reactive CD8+ T cells after BMT, suggesting that induction of host inflammatory response could break antigen ignorance. Introducing the GP33 antigen into BM cells led to deletion of anti-host reactive CD8+ T cells. Conclusion: We found that after BMT anti-host reactive CD8+ T cells ignored host antigen in recipients and that they were only deleted when host antigen was present in hematopoietic cells. Moreover, LPS-induced immune activation contributed to induction of alloreactivity of anti-host reactive CD8+ T cells after BMT.

  10. Non-major histocompatibility complex-restricted cytotoxic activity of blood mononuclear cells stimulated with secreted mycobacterial proteins and other mycobacterial antigens

    DEFF Research Database (Denmark)

    Ravn, P; Pedersen, B K

    1994-01-01

    Several observations indicate that non-major histocompatibility complex (MHC)-restricted cytotoxicity, mediated for example by natural killer cells and lymphokine-activated killer cells, may serve as an important antimicrobial defense mechanism. The purpose of the present study was to investigate...... the influences of different mycobacterial antigens on non-MHC-restricted cytotoxicity and further to investigate the ways by which various lymphocyte subpopulations contribute to the development of this cytotoxicity. Non-MHC-restricted cytotoxicity was induced following stimulation of mononuclear cells......+ cells proliferated and expressed interleukin-2 receptors following stimulation with mycobacterial antigens. Depletion studies after antigen stimulation showed that the cytotoxic effector cells were CD16+ CD56+ and CD4-; the CD4+ cells alone did not mediate non-MHC-restricted cytotoxicity. To evaluate...

  11. Targeting proliferating cell nuclear antigen and its protein interactions induces apoptosis in multiple myeloma cells.

    Directory of Open Access Journals (Sweden)

    Rebekka Müller

    Full Text Available Multiple myeloma is a hematological cancer that is considered incurable despite advances in treatment strategy during the last decade. Therapies targeting single pathways are unlikely to succeed due to the heterogeneous nature of the malignancy. Proliferating cell nuclear antigen (PCNA is a multifunctional protein essential for DNA replication and repair that is often overexpressed in cancer cells. Many proteins involved in the cellular stress response interact with PCNA through the five amino acid sequence AlkB homologue 2 PCNA-interacting motif (APIM. Thus inhibiting PCNA's protein interactions may be a good strategy to target multiple pathways simultaneously. We initially found that overexpression of peptides containing the APIM sequence increases the sensitivity of cancer cells to contemporary therapeutics. Here we have designed a cell-penetrating APIM-containing peptide, ATX-101, that targets PCNA and show that it has anti-myeloma activity. We found that ATX-101 induced apoptosis in multiple myeloma cell lines and primary cancer cells, while bone marrow stromal cells and primary healthy lymphocytes were much less sensitive. ATX-101-induced apoptosis was caspase-dependent and cell cycle phase-independent. ATX-101 also increased multiple myeloma cells' sensitivity against melphalan, a DNA damaging agent commonly used for treatment of multiple myeloma. In a xenograft mouse model, ATX-101 was well tolerated and increased the anti-tumor activity of melphalan. Therefore, targeting PCNA by ATX-101 may be a novel strategy in multiple myeloma treatment.

  12. Serum squamous cell carcinoma antigen and CYFRA 21-1 in cervical cancer treatment

    International Nuclear Information System (INIS)

    Purpose: To analyze whether serum squamous cell carcinoma (SCC) antigen and cytokeratin-19 fragments (CYFRA) levels can assist in selecting patients with locally advanced cervical cancer who will benefit from combined treatment or additive surgery. Methods and Materials: Of 114 patients with cervical cancer Stage IB-IV, the first 39 patients received radiotherapy, the following 75 patients received identical radiotherapy plus concomitant chemotherapy (3 cycles of carboplatin and 5-fluorouracil). SCC antigen and CYFRA 21-1 serum levels were measured before treatment, after therapy, and during follow-up. Baseline tumor markers were related to tumor stage and size and clinical outcome. Results: Before treatment, SCC antigen was elevated (>1.9 μg/L) in 60% and CYFRA 21-1 (>2.2 μg/L) in 46% of patients. For all patients, disease-free survival (DFS) was better after combined treatment (67% vs. 43%, p<0.0005). For patients with elevated baseline SCC antigen, DFS was better after combination therapy (67% vs. 27%, p=0.001) which resulted more frequently in a normal SCC antigen (93% vs. 65%, p=0.004). In contrast, in those with a normal baseline CYFRA 21-1, combined therapy resulted in a better DFS (p=0.04). Patients who achieved a normal SCC antigen or CYFRA 21-1 after treatment had a better DFS (respectively 63 vs. 17% and 64 vs. 30%). Elevated SCC antigen posttreatment indicated residual tumor in 11/12 patients (92%), elevated CYFRA 21-1 in 7/10 patients (70%). Forty-seven patients had a tumor recurrence. At recurrence, SCC antigen was raised in 70% and CYFRA 21-1 in 69%. Conclusions: In patients with an elevated pretreatment SCC antigen, SCC antigen normalized more frequently with combined treatment and those patients had a better DFS. Elevated SCC antigen or CYFRA 21-1 levels after treatment completion indicated residual tumor in respectively 92% and 70%. The presence of elevated posttreatment levels of SCC antigen or CYFRA 21-1 indicates the need for additional

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-05-08

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

  14. The B cell antigen receptor and overexpression of MYC can cooperate in the genesis of B cell lymphomas.

    Directory of Open Access Journals (Sweden)

    Yosef Refaeli

    2008-06-01

    Full Text Available A variety of circumstantial evidence from humans has implicated the B cell antigen receptor (BCR in the genesis of B cell lymphomas. We generated mouse models designed to test this possibility directly, and we found that both the constitutive and antigen-stimulated state of a clonal BCR affected the rate and outcome of lymphomagenesis initiated by the proto-oncogene MYC. The tumors that arose in the presence of constitutive BCR differed from those initiated by MYC alone and resembled chronic B cell lymphocytic leukemia/lymphoma (B-CLL, whereas those that arose in response to antigen stimulation resembled large B-cell lymphomas, particularly Burkitt lymphoma (BL. We linked the genesis of the BL-like tumors to antigen stimulus in three ways. First, in reconstruction experiments, stimulation of B cells by an autoantigen in the presence of overexpressed MYC gave rise to BL-like tumors that were, in turn, dependent on both MYC and the antigen for survival and proliferation. Second, genetic disruption of the pathway that mediates signaling from the BCR promptly killed cells of the BL-like tumors as well as the tumors resembling B-CLL. And third, growth of the murine BL could be inhibited by any of three distinctive immunosuppressants, in accord with the dependence of the tumors on antigen-induced signaling. Together, our results provide direct evidence that antigenic stimulation can participate in lymphomagenesis, point to a potential role for the constitutive BCR as well, and sustain the view that the constitutive BCR gives rise to signals different from those elicited by antigen. The mouse models described here should be useful in exploring further the pathogenesis of lymphomas, and in preclinical testing of new therapeutics.

  15. Dexamethasone and Monophosphoryl Lipid A-Modulated Dendritic Cells Promote Antigen-Specific Tolerogenic Properties on Naive and Memory CD4+ T Cells

    Science.gov (United States)

    Maggi, Jaxaira; Schinnerling, Katina; Pesce, Bárbara; Hilkens, Catharien M.; Catalán, Diego; Aguillón, Juan C.

    2016-01-01

    Tolerogenic dendritic cells (DCs) are a promising tool to control T cell-mediated autoimmunity. Here, we evaluate the ability of dexamethasone-modulated and monophosphoryl lipid A (MPLA)-activated DCs [MPLA-tolerogenic DCs (tDCs)] to exert immunomodulatory effects on naive and memory CD4+ T cells in an antigen-specific manner. For this purpose, MPLA-tDCs were loaded with purified protein derivative (PPD) as antigen and co-cultured with autologous naive or memory CD4+ T cells. Lymphocytes were re-challenged with autologous PPD-pulsed mature DCs (mDCs), evaluating proliferation and cytokine production by flow cytometry. On primed-naive CD4+ T cells, the expression of regulatory T cell markers was evaluated and their suppressive ability was assessed in autologous co-cultures with CD4+ effector T cells and PPD-pulsed mDCs. We detected that memory CD4+ T cells primed by MPLA-tDCs presented reduced proliferation and proinflammatory cytokine expression in response to PPD and were refractory to subsequent stimulation. Naive CD4+ T cells were instructed by MPLA-tDCs to be hyporesponsive to antigen-specific restimulation and to suppress the induction of T helper cell type 1 and 17 responses. In conclusion, MPLA-tDCs are able to modulate antigen-specific responses of both naive and memory CD4+ T cells and might be a promising strategy to “turn off” self-reactive CD4+ effector T cells in autoimmunity.

  16. T Cell Receptors that Recognize the Tyrosinase Tumor Antigen | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    The National Cancer Institute, Surgery Branch, Tumor Immunology Section, is seeking statements of capability or interest from parties interested in collaborative research to further develop, evaluate, or commercialize T Cells Attacking Cancer: T Cell Receptors that Recognize the Tyrosinase Tumor Antigen

  17. The clinical value of squamous cell carcinoma antigen in cancer of the uterine cervix

    NARCIS (Netherlands)

    de Bruijn, HWA; Duk, JM; van der Zee, AGJ; Pras, E; Willemse, PHB; Hollema, H; Mourits, MJE; de Vries, EGE; Aalders, JG; Boonstra, J.

    1998-01-01

    A review is given of the clinical use and interpretation of serum tumor marker levels during the treatment of patients with cancer of the uterine cervix, Pretreatment serum squamous cell carcinoma (SCC) antigen provides a new prognostic factor in early stage squamous cell carcinoma of the uterine ce

  18. Discovering naturally processed antigenic determinants that confer protective T cell immunity

    DEFF Research Database (Denmark)

    Gilchuk, Pavlo; Spencer, Charles T; Conant, Stephanie B;

    2013-01-01

    CD8+ T cells (TCD8) confer protective immunity against many infectious diseases, suggesting that microbial TCD8 determinants are promising vaccine targets. Nevertheless, current T cell antigen identification approaches do not discern which epitopes drive protective immunity during active infectio...

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

    Science.gov (United States)

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

    2016-03-30

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

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

    Science.gov (United States)

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

    2016-03-30

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

  1. Squamous cell carcinoma antigen isoforms in serum from cervical cancer patients

    NARCIS (Netherlands)

    Roijer, E; de Bruijn, HWA; Dahlen, U; ten Hoor, K; Lundin, M; Nilsson, K; Soderstrom, K; Nilsson, O

    2006-01-01

    Squamous cell carcinoma antigen (SCCA) is a serological marker of squamous cell carcinomas (SCC). To study whether any of the SCCA isoforms would provide additional and more specific/sensitive clinical information than total SCCA, immunoassays specific for the different forms of SCCA (free SCCA2, to

  2. A rendezvous before rejection: Where do T cells meet transplant antigens?

    OpenAIRE

    Briscoe, David M.; Sayegh, Mohamed H.

    2002-01-01

    Interactions between recipient T cells and donor endothelial graft cells may be an important mechanism for both acute and chronic rejection of vascularized allografts. This finding provides a starting point for investigations to develop novel ways of inducing long-lasting immunologic tolerance to donor antigens.

  3. Genetic Variant as a Selection Marker for Anti–Prostate Stem Cell Antigen Immunotherapy of Bladder Cancer

    OpenAIRE

    Kohaar, Indu; Porter-Gill, Patricia; Lenz, Petra; Fu, Yi-Ping; Mumy, Adam; Tang, Wei; Apolo, Andrea B.; Rothman, Nathaniel; Baris, Dalsu; Schned, Alan R.; Ylaya, Kris; Schwenn, Molly; Johnson, Alison; Jones, Michael; Kida, Masatoshi

    2012-01-01

    A monoclonal antibody against prostate stem cell antigen (PSCA) has emerged as a novel cancer therapy currently being tested in clinical trials for prostate and pancreatic cancers, but this treatment is likely to be efficient only in patients with PSCA-expressing tumors. The present study demonstrates that a genetic variant (rs2294008) discovered by bladder cancer genome-wide association studies is a strong predictor of PSCA protein expression in bladder tumors, as measured by two-sided multi...

  4. Prospects for chimeric antigen receptor (CAR) γδ T cells: A potential game changer for adoptive T cell cancer immunotherapy.

    Science.gov (United States)

    Mirzaei, Hamid Reza; Mirzaei, Hamed; Lee, Sang Yun; Hadjati, Jamshid; Till, Brian G

    2016-10-01

    Excitement is growing for therapies that harness the power of patients' immune systems to combat their diseases. One approach to immunotherapy involves engineering patients' own T cells to express a chimeric antigen receptor (CAR) to treat advanced cancers, particularly those refractory to conventional therapeutic agents. Although these engineered immune cells have made remarkable strides in the treatment of patients with certain hematologic malignancies, success with solid tumors has been limited, probably due to immunosuppressive mechanisms in the tumor niche. In nearly all studies to date, T cells bearing αβ receptors have been used to generate CAR T cells. In this review, we highlight biological characteristics of γδ T cells that are distinct from those of αβ T cells, including homing to epithelial and mucosal tissues and unique functions such as direct antigen recognition, lack of alloreactivity, and ability to present antigens. We offer our perspective that these features make γδ T cells promising for use in cellular therapy against several types of solid tumors, including melanoma and gastrointestinal cancers. Engineered γδ T cells should be considered as a new platform for adoptive T cell cancer therapy for mucosal tumors. PMID:27392648

  5. Identification of putative cathepsin S in mangrove red snapper Lutjanus argentimaculatus and its role in antigen presentation.

    Science.gov (United States)

    Zhou, Jin; Li, Lei; Cai, Zhong-Hua

    2012-05-01

    Cathepsin S (CTSS) is a key enzyme employed in the histocompatibility complex (MHC) class II-restricted antigens, which are presented by processing class II-associated invariant chains and loaded antigen peptides into class II molecules. To date, little is known about the character and function of CTSS in fish. In the present study, we screened and identified a CTSS cDNA sequence from the mangrove red snapper head kidney cDNA library. The full-length CTSS cDNA contained 1339-bp nucleotide acids encoding 337 amino acids. The sequence shared high identity and similarity with other known cathepsins, especially CTSS (about 56-78% and 79-89%, respectively). Like other cathepsins, the deduced peptide consisted of regions with N-terminal signal peptides, propeptides, and mature peptides. A typical ERWNIN motif in L-like cathepsins and three conservative catalytic activity sites forming a catalytic triad active center were respectively identified in the pro-peptide and mature peptide regions of CTSS. Phylogenetic analysis revealed that mangrove red snapper CTSS was located in the CTSS clade belonging to the L-like cathepsin group, and evolved from the same ancestry. To further characterize the biological activity of the putative CTSS of mangrove snapper, CTSS was expressed in Escherichia coli M15 strains. Like other mammalian CTSS, the recombinant CTSS (rCTSS) had autocatalytic activation properties, can remove pro-peptides, and can release active mature peptides. Active CTSS had the ability to catalyze Z-Phe-Arg-AMC substrates in acidic conditions (pH 5.0) and weak alkaline environments (pH 7.5); this activity could be blocked by the cysteine protease inhibitor E-64. Active CTSS can process recombinant Ii chains (invariant chains) in a stepwise manner in vitro. The results indicate that mangrove red snapper CTSS is a lysosomal cysteine protease family member with a key role in antigen processing in fish.

  6. Serological survey of normal humans for natural antibody to cell surface antigens of melanoma.

    Science.gov (United States)

    Houghton, A N; Taormina, M C; Ikeda, H; Watanabe, T; Oettgen, H F; Old, L J

    1980-01-01

    Sera of 106 normal adult men were tested for antibodies reacting with cell surface antigens of three established lines of cultured malignant melanoma. Positive reactions with a protein A assay for IgG antibodies were extremely rare (1-2%). The frequency of positive reactions with assays for IgM antibodies was higher: 5-15% in immune adherence assays and 55-82% in anti-C3 mixed hemadsorption assays. After low-titered sera and sera reacting with fetal calf serum components, conventional alloantigens, and widely distributed class 3 antigens were excluded, sera from seven individuals (one with IgG antibody and six with IgM antibodies) were selected for detailed analysis. The serum containing the IgG antibody came from a healthy 65-year-old Caucasian man; titers of antibody in his serum ranged from < 1/10 to 1/40,000 in tests with different melanoma cell lines. This IgG antibody identifies a differentiation antigen of melanocytes, provisionally designated Mel 1, that distinguishes two classes of melanomas: 22 melanoma cell lines typed Mel 1+ and 17 types Mel 1-. Mel 1 is expressed by fetal fibroblasts but not adult fibroblasts and can be found on a proportion of cultured epithelial cancer cell lines (5 out of 23) but not on glioma or B-cell lines. The melanoma antigens detected by the naturally occurring IgM antibodies are serologically unrelated to Mel 1 but, like Mel 1, appear to be differentiation antigens that distinguish subsets of melanoma. These IgM antibodies detect antigens that are identical or closely related to the AH antigen, a melanoma surface antigen that was initially defined by autologous antibody in a patient with melanoma. In view of the immunogenicity of both Mel 1 and the AH antigens in humans and their occurrence on more than 50% of melanomas, it remains to be seen whether antibody to these antigens can be elicited by specific vaccination of seronegative melanoma patients and whether this will have an influence on the clinical course of the disease

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

    Science.gov (United States)

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

    2016-08-01

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

  8. An unusual presentation of Langerhans cell histiocytosis

    Directory of Open Access Journals (Sweden)

    Palak Agarwal

    2014-01-01

    Full Text Available Langerhans cell histiocytosis (LCH is a relatively rare and unique disease. An incidence of 7.9% in the jaws is reported. We report a case of 9-year-old male child referred to us from dental outpatient department, who presented with a firm swelling in right lower jaw along with bilateral submandibular lymphadenopathy for 1-month. Fine-needle aspiration was done from lytic lesion in the body of mandible and multiple smears were prepared. On the basis of the clinical and cytomorphological findings, a diagnosis of LCH was suggested. The diagnosis was confirmed on histology. Thus, a high possibility of LCH should be considered in children presenting with lytic lesions in head and neck region.

  9. An unusual presentation of Langerhans cell histiocytosis

    Science.gov (United States)

    Agarwal, Palak; Kaushal, Manju

    2014-01-01

    Langerhans cell histiocytosis (LCH) is a relatively rare and unique disease. An incidence of 7.9% in the jaws is reported. We report a case of 9-year-old male child referred to us from dental outpatient department, who presented with a firm swelling in right lower jaw along with bilateral submandibular lymphadenopathy for 1-month. Fine-needle aspiration was done from lytic lesion in the body of mandible and multiple smears were prepared. On the basis of the clinical and cytomorphological findings, a diagnosis of LCH was suggested. The diagnosis was confirmed on histology. Thus, a high possibility of LCH should be considered in children presenting with lytic lesions in head and neck region. PMID:25745295

  10. Basal Cell Nevus Syndrome. A Case Presentation

    Directory of Open Access Journals (Sweden)

    Ángel Luis Cruz Leiva

    2007-12-01

    Full Text Available Basal Cell Nevus Syndrome is an infrequent entity of very low incidence according to reports in medical literature. It is characterized by considerable groups of alterations which are presented in the organism in a variable way, and with localized lesions in the maxillofacial area. A 61 year-old white male patient who lives in the urban area of Cienfuegos city is presented. He has family references of numerous physical deformities since he was born such as mental retardation, presence of moles since the first decade of his life and augmentation of the mandibular body volume. The diagnosis was keratocysts based on the clinical and radiological examinations as well as histopathological studies.

  11. Merkel Cell Polyomavirus Small T Antigen Targets the NEMO Adaptor Protein To Disrupt Inflammatory Signaling

    OpenAIRE

    Griffiths, David A.; Abdul-Sada, Hussein; Knight, Laura M.; Jackson, Brian R.; Richards, Kathryn; Prescott, Emma L.; Peach, A. Howard S.; Blair, G. Eric; MacDonald, Andrew; Whitehouse, Adrian

    2013-01-01

    Merkel cell carcinoma (MCC) is a highly aggressive nonmelanoma skin cancer arising from epidermal mechanoreceptor Merkel cells. In 2008, a novel human polyomavirus, Merkel cell polyomavirus (MCPyV), was identified and is strongly implicated in MCC pathogenesis. Currently, little is known regarding the virus-host cell interactions which support virus replication and virus-induced mechanisms in cellular transformation and metastasis. Here we identify a new function of MCPyV small T antigen (ST)...

  12. Proliferating cell nuclear antigen: a marker for hepatocellular proliferation in rodents.

    OpenAIRE

    Eldrige, S R; Butterworth, B E; Goldsworthy, T L

    1993-01-01

    Two different markers for quantitating cell proliferation were evaluated in livers of control and chemically treated mice and rats. Proliferating cell nuclear antigen (PCNA), an endogenous cell replication marker, and bromodeoxyuridine (BrdU), an exogenously administered DNA precursor label, were detected in formalin-fixed, paraffin-embedded tissues using immunohistochemical techniques. The percentage of cells in S phase (labeling indexes, LI) evaluated as PCNA- or BrdU-positive hepatocellula...

  13. Long-term in vivo provision of antigen-specific T cell immunity by programming hematopoietic stem cells

    Science.gov (United States)

    Yang, Lili; Baltimore, David

    2005-03-01

    A method to genetically program mouse hematopoietic stem cells to develop into functional CD8 or CD4 T cells of defined specificity in vivo is described. For this purpose, a bicistronic retroviral vector was engineered that efficiently delivers genes for both and chains of T cell receptor (TCR) to hematopoietic stem cells. When modified cell populations were used to reconstruct the hematopoietic lineages of recipient mice, significant percentages of antigen-specific CD8 or CD4 T cells were observed. These cells expressed normal surface markers and responded to peptide antigen stimulation by proliferation and cytokine production. Moreover, they could mature into memory cells after peptide stimulation. Using TCRs specific for a model tumor antigen, we found that the recipient mice were able to partially resist a challenge with tumor cells carrying the antigen. By combining cells modified with CD8- and CD4-specific TCRs, and boosting with dendritic cells pulsed with cognate peptides, complete suppression of tumor could be achieved and even tumors that had become established would regress and be eliminated after dendritic cell/peptide immunization. This methodology of "instructive immunotherapy" could be developed for controlling the growth of human tumors and attacking established pathogens.

  14. Tumorigenic activity of Merkel cell polyomavirus T antigens expressed in the stratified epithelium of mice

    Science.gov (United States)

    Spurgeon, Megan E.; Cheng, Jingwei; Bronson, Roderick T.; Lambert, Paul F.; DeCaprio, James A.

    2015-01-01

    Merkel cell polyomavirus (MCPyV) is frequently associated with Merkel cell carcinoma (MCC), a highly aggressive neuroendocrine skin cancer. Most MCC tumors contain integrated copies of the viral genome with persistent expression of the MCPyV large T (LT) and small T (ST) antigen. MCPyV isolated from MCC typically contain wild type ST but truncated forms of LT that retain the N-terminus but delete the C-terminus and render LT incapable of supporting virus replication. To determine the oncogenic activity of MCC tumor-derived T antigens in vivo, a conditional, tissue-specific mouse model was developed. Keratin 14-mediated Cre recombinase expression induced expression of MCPyV T antigens in stratified squamous epithelial cells and Merkel cells of the skin epidermis. Mice expressing MCPyV T antigens developed hyperplasia, hyperkeratosis, and acanthosis of the skin with additional abnormalities in whisker pads, footpads and eyes. Nearly half of the mice also developed cutaneous papillomas. Evidence for neoplastic progression within stratified epithelia included increased cellular proliferation, unscheduled DNA synthesis, increased E2F-responsive genes levels, disrupted differentiation, and presence of a DNA damage response. These results indicate that MCPyV T antigens are tumorigenic in vivo, consistent with their suspected etiological role in human cancer. PMID:25596282

  15. Tumorigenic activity of merkel cell polyomavirus T antigens expressed in the stratified epithelium of mice.

    Science.gov (United States)

    Spurgeon, Megan E; Cheng, Jingwei; Bronson, Roderick T; Lambert, Paul F; DeCaprio, James A

    2015-03-15

    Merkel cell polyomavirus (MCPyV) is frequently associated with Merkel cell carcinoma (MCC), a highly aggressive neuroendocrine skin cancer. Most MCC tumors contain integrated copies of the viral genome with persistent expression of the MCPyV large T (LT) and small T (ST) antigen. MCPyV isolated from MCC typically contains wild-type ST but truncated forms of LT that retain the N-terminus but delete the C-terminus and render LT incapable of supporting virus replication. To determine the oncogenic activity of MCC tumor-derived T antigens in vivo, a conditional, tissue-specific mouse model was developed. Keratin 14-mediated Cre recombinase expression induced expression of MCPyV T antigens in stratified squamous epithelial cells and Merkel cells of the skin epidermis. Mice expressing MCPyV T antigens developed hyperplasia, hyperkeratosis, and acanthosis of the skin with additional abnormalities in whisker pads, footpads, and eyes. Nearly half of the mice also developed cutaneous papillomas. Evidence for neoplastic progression within stratified epithelia included increased cellular proliferation, unscheduled DNA synthesis, increased E2F-responsive genes levels, disrupted differentiation, and presence of a DNA damage response. These results indicate that MCPyV T antigens are tumorigenic in vivo, consistent with their suspected etiologic role in human cancer. PMID:25596282

  16. Expression of I-A and I-E,C region-coded Ia antigens on functional B cell subpopulations.

    Science.gov (United States)

    Frelinger, J A; Hibbler, F J; Hill, S W

    1978-12-01

    Ia antigens from specific subregions have been examined on functional B cell populations. Expression of both I-A and I-E,C region antigens was demonstrated on cells required for both lipopolysaccharide mitogenesis and polyclonal activation. Similar I-A and I-E,C subregion expression was found on cells required for response to the T-independent antigen, polyvinylpyrrolidone. TNP-specific IgM and hen egg lysozyme-specific IgG plaque-forming cells also express I-A and I-E,C region antigens. No evidence was found for an Ia- population responsive in the systems tested. Further, no evidence of preferential expression of I-A or I-E,C region antigens was observed in any system examined. Therefore, it appears that B cells express both I-A and I-E,C region-coded Ia antigens.

  17. Near-infrared labeled, ovalbumin loaded polymeric nanoparticles based on a hydrophilic polyester as model vaccine: In vivo tracking and evaluation of antigen-specific CD8(+) T cell immune response.

    Science.gov (United States)

    Rahimian, Sima; Kleinovink, Jan Willem; Fransen, Marieke F; Mezzanotte, Laura; Gold, Henrik; Wisse, Patrick; Overkleeft, Hermen; Amidi, Maryam; Jiskoot, Wim; Löwik, Clemens W; Ossendorp, Ferry; Hennink, Wim E

    2015-01-01

    Particulate antigen delivery systems aimed at the induction of antigen-specific T cells form a promising approach in immunotherapy to replace pharmacokinetically unfavorable soluble antigen formulations. In this study, we developed a delivery system using the model protein antigen ovalbumin (OVA) encapsulated in nanoparticles based on the hydrophilic polyester poly(lactide-co-hydroxymethylglycolic acid) (pLHMGA). Spherical nanoparticles with size 300-400 nm were prepared and characterized and showed a strong ability to deliver antigen to dendritic cells for cross-presentation to antigen-specific T cells in vitro. Using near-infrared (NIR) fluorescent dyes covalently linked to both the nanoparticle and the encapsulated OVA antigen, we tracked the fate of this formulation in mice. We observed that the antigen and the nanoparticles are efficiently co-transported from the injection site to the draining lymph nodes, in a more gradual and durable manner than soluble OVA protein. OVA-loaded pLHMGA nanoparticles efficiently induced antigen cross-presentation to OVA-specific CD8+ T cells in the lymph nodes, superior to soluble OVA vaccination. Together, these data show the potential of pLHMGA nanoparticles as attractive antigen delivery vehicles.

  18. Identification of Leishmania proteins preferentially released in infected cells using change mediated antigen technology (CMAT.

    Directory of Open Access Journals (Sweden)

    Peter E Kima

    Full Text Available Although Leishmania parasites have been shown to modulate their host cell's responses to multiple stimuli, there is limited evidence that parasite molecules are released into infected cells. In this study, we present an implementation of the change mediated antigen technology (CMAT to identify parasite molecules that are preferentially expressed in infected cells. Sera from mice immunized with cell lysates prepared from L. donovani or L. pifanoi-infected macrophages were adsorbed with lysates of axenically grown amastigotes of L. donovani or L. pifanoi, respectively, as well as uninfected macrophages. The sera were then used to screen inducible parasite expression libraries constructed with genomic DNA. Eleven clones from the L. pifanoi and the L. donovani screen were selected to evaluate the characteristics of the molecules identified by this approach. The CMAT screen identified genes whose homologs encode molecules with unknown function as well as genes that had previously been shown to be preferentially expressed in the amastigote form of the parasite. In addition a variant of Tryparedoxin peroxidase that is preferentially expressed within infected cells was identified. Antisera that were then raised to recombinant products of the clones were used to validate that the endogenous molecules are preferentially expressed in infected cells. Evaluation of the distribution of the endogenous molecules in infected cells showed that some of these molecules are secreted into parasitophorous vacuoles (PVs and that they then traffic out of PVs in vesicles with distinct morphologies. This study is a proof of concept study that the CMAT approach can be applied to identify putative Leishmania parasite effectors molecules that are preferentially expressed in infected cells. In addition we provide evidence that Leishmania molecules traffic out of the PV into the host cell cytosol and nucleus.

  19. Identification of ATP synthase beta subunit (ATPB on the cell surface as a non-small cell lung cancer (NSCLC associated antigen

    Directory of Open Access Journals (Sweden)

    Qian Zhi

    2009-01-01

    Full Text Available Abstract Background Antibody-based immuneotherapy has achieved some success for cancer. But the main problem is that only a few tumor-associated antigens or therapeutic targets have been known to us so far. It is essential to identify more immunogenic antigens (especially cellular membrane markers for tumor diagnosis and therapy. Methods The membrane proteins of lung adenocarcinoma cell line A549 were used to immunize the BALB/c mice. A monoclonal antibody 4E7 (McAb4E7 was produced with hybridoma technique. MTT cell proliferation assay was carried out to evaluate the inhibitory effect of McAb4E7 on A549 cells. Flow cytometric assay, immunohistochemistry, western blot and proteomic technologies based on 2-DE and mass spectrometry were employed to detect and identify the corresponding antigen of McAb4E7. Results The monoclonal antibody 4E7 (McAb4E7 specific against A549 cells was produced, which exhibited inhibitory effect on the proliferation of A549 cells. By the proteomic technologies, we identified that ATP synthase beta subunit (ATPB was the corresponding antigen of McAb4E7. Then, flow cytometric analysis demonstrated the localization of the targeting antigen of McAb4E7 was on the A549 cells surface. Furthermore, immunohistochemstry showed that the antigen of McAb4E7 mainly aberrantly expressed in tumor cellular membrane in non-small cell lung cancer (NSCLC, but not in small cell lung cancer (SCLC. The rate of ectopic expressed ATPB in the cellular membrane in lung adenocarcinoma, squamous carcinoma and their adjacent nontumourous lung tissues was 71.88%, 66.67% and 25.81% respectively. Conclusion In the present study, we identified that the ectopic ATPB in tumor cellular membrane was the non-small cell lung cancer (NSCLC associated antigen. ATPB may be a potential biomarker and therapeutic target for the immunotherapy of NSCLC.

  20. Chimeric Antigen Receptor-Engineered T Cells for Immunotherapy of Cancer

    Directory of Open Access Journals (Sweden)

    Marc Cartellieri

    2010-01-01

    Full Text Available CD4+ and CD8+ T lymphocytes are powerful components of adaptive immunity, which essentially contribute to the elimination of tumors. Due to their cytotoxic capacity, T cells emerged as attractive candidates for specific immunotherapy of cancer. A promising approach is the genetic modification of T cells with chimeric antigen receptors (CARs. First generation CARs consist of a binding moiety specifically recognizing a tumor cell surface antigen and a lymphocyte activating signaling chain. The CAR-mediated recognition induces cytokine production and tumor-directed cytotoxicity of T cells. Second and third generation CARs include signal sequences from various costimulatory molecules resulting in enhanced T-cell persistence and sustained antitumor reaction. Clinical trials revealed that the adoptive transfer of T cells engineered with first generation CARs represents a feasible concept for the induction of clinical responses in some tumor patients. However, further improvement is required, which may be achieved by second or third generation CAR-engrafted T cells.

  1. HCA520, A NOVEL TUMOR ASSOCIATED ANTIGEN, INVOLVED IN CELL PROLIFERATION AND APOPTOSIS

    Institute of Scientific and Technical Information of China (English)

    杨美香; 曲迅; 刘福利; 郑广娟

    2003-01-01

    Objective: Tumor associated antigen encoding gene HCA520 (AF146019) was identified by screening a human hepatocellular carcinoma expressing cDNA library using SEREX technique. In this experiment we studied the effect of HCA520 on cell proliferation and apoptosis. Methods: Gene HCA520 was gained by PCR and transfected into 293 cells. The stable expression cells were obtained by G418 selection. The cell proliferation was measured by [3H]-TdR uptake and apoptosis assay was measured by FACS. Results: Eukaryotic expression plasmid pcDNA3-HCA520 was constructed and its stable transfectants were obtained. Overexpression of HCA520 inhibited the cell proliferation and enhanced cell apoptosis after serum deprivation. Conclusion: HCA520 is a novel tumor associated antigen that can affect cell proliferation and apoptosis.

  2. The immunodominant Eimeria acervulina sporozoite antigen previously described as p160/p240 is a 19-kilodalton antigen present in several Eimeria species.

    Science.gov (United States)

    Laurent, F; Bourdieu, C; Kazanji, M; Yvoré, P; Péry, P

    1994-01-01

    A lambda Zap II cDNA expression library, constructed from Eimeria acervulina (PAPa46 strain) sporulated oocyst stage, was screened with sera raised to E. acervulina or Eimeria tenella oocysts in order to isolate clones coding for antigens common to the two species. Most of the clones isolated were derived from the same gene. Antisera raised to a recombinant glutathione-S-transferase fusion protein 1P reacted with an antigen of 19 kDa in immunoblot of E. acervulina sporulated and unsporulated oocysts. Immunofluorescence of E. acervulina sporozoites indicated that the antigen is located in the cytoplasm. The anti-1P antisera reacted on immunoblots of E. tenella with a 19-kDa antigen and by immunofluorescence on E. tenella, Eimeria maxima and Eimeria falciformis sporozoites, indicating that the antigen is conserved in Eimeria species. DNA sequencing indicated that the sequence was almost identical to that of clone cSZ1 previously described by Jenkins et al. using E. acervulina strain #12. The 1P insert hybridized to a 1150-nt mRNA from E. acervulina PAPa46 strain and strain #12, a size consistent with the observed molecular weight of the protein.

  3. Frequencies of red blood cell major blood group antigens and phenotypes in the Chinese Han population from Mainland China.

    Science.gov (United States)

    Yu, Y; Ma, C; Sun, X; Guan, X; Zhang, X; Saldanha, J; Chen, L; Wang, D

    2016-08-01

    Alloantibodies directed to red blood cell (RBC) antigens play an important role in alloimmune-mediated haemolytic transfusion reactions and haemolytic disease of the foetus and newborn. The frequencies and phenotypes of RBC antigens are different in populations from different geographic areas and races. However, the data on major blood group antigens in the Chinese Han population from Mainland China are still very limited; thus, we aimed to investigate them in this study. A total of 1412 unrelated voluntary Chinese Han blood donors were randomly recruited. All donors were typed for blood group antigens: D, C, c, E, e, C(w) , Jk(a) , Jk(b) ,M, N, S, s, Le(a) , Le(b) , K, k. Kp(a) , Kp(b) , Fy(a) , Fy(b) , Lu(a) , Lu(b) , P1 and Di(a) using serological technology. Calculations of antigen and phenotype frequencies were expressed as percentages and for allele frequencies under the standard assumption of Hardy-Weinberg equilibrium. Amongst the Rh antigens, D was the most common (98.94%) followed by e (92.28%), C (88.81%), c (58.43%), E (50.78%) and C(w) (0.07%) with DCe/DCe (R1 R1 , 40.72%) being the most common phenotype. In the Kell blood group system, k was present in 100% of the donors and a rare phenotype, Kp (a+b+), was found in 0.28% of the donors. For the Kidd and Duffy blood group systems, Jk (a+b+) and Fy (a+b-) were the most common phenotypes (44.05% and 84.35%, respectively). In the MNS blood group system, M+N+S-s+ (45.54%) was the most common, whereas M+N-S-s- and M-N+S-s- were not found. The rare Lu (a-b-) and Lu (a+b+) phenotypes were identified in 0.43% and 1.13% of the donors, respectively. Le(a) and Le(b) were seen in 17.92% and 63.03% of donors, respectively. The frequency of Di(a) was 4.75%, which was higher than in the Chinese population in Taiwan region or the Caucasian and Black populations (P < 0.0001). This study systematically describes the frequencies of 24 blood group antigens in the Chinese Han population from Mainland China. The data can

  4. Interferon-induced changes in expression of antigens defined by monoclonal antibodies on malignant and nonmalignant mononuclear hematopoietic cells

    DEFF Research Database (Denmark)

    Hokland, M; Ritz, J; Hokland, P

    1983-01-01

    The effect of alpha interferon (alpha IFN) on the expression of histocompatibility--as well as differentiation antigens on normal and malignant hematopoietic mononuclear cells--were investigated by cell cytofluorometry using a panel of monoclonal antibodies (MoAbs). An increase in the expression...... of HLA-antigens detected by beta 2-Microglobulin (beta 2-M) could be demonstrated for peripheral blood mononuclear cells, non-T cells, Null cells, activated T cells, fetal thymocytes, adherent cells, and on four malignant non-T lymphoblastoid cell lines. In contrast, no significant differences were...... observed in the expression of antigens specific for B-lymphocytes (B1), T-lymphocytes (T3, T4, T6, T8, T11), NK-cells (901) and adherent cells (Mo1-4). Likewise, the expression of Ia-antigens remained unaltered on non-T cells, Null cells, and monocytes. The only other effect of IFN was an increase...

  5. Subdominant H60 antigen-specific CD8 T-cell response precedes dominant H4 antigen-specific response during the initial phase of allogenic skin graft rejection.

    Science.gov (United States)

    Yoo, Kang Il; Jeon, Ji Yeong; Ryu, Su Jeong; Nam, Giri; Youn, Hyewon; Choi, Eun Young

    2015-02-13

    In allogeneic transplantation, including the B6 anti-BALB.B settings, H60 and H4 are two representative dominant minor histocompatibility antigens that induce strong CD8 T-cell responses. With different distribution patterns, H60 expression is restricted to hematopoietic cells, whereas H4 is ubiquitously expressed. H60-specific CD8 T-cell response has been known to be dominant in most cases of B6 anti-BALB.B allo-responses, except in the case of skin transplantation. To understand the mechanism underlying the subdominance of H60 during allogeneic skin transplantation, we investigated the dynamics of the H60-specific CD8 T cells in B6 mice transplanted with allogeneic BALB.B tail skin. Unexpectedly, longitudinal bioluminescence imaging and flow cytometric analyses revealed that H60-specific CD8 T cells were not always subdominant to H4-specific cells but instead showed a brief dominance before the H4 response became predominant. H60-specific CD8 T cells could expand in the draining lymph node and migrate to the BALB.B allografts, indicating their active participation in the anti-BALB.B allo-response. Enhancing the frequencies of H60-reactive CD8 T cells prior to skin transplantation reversed the immune hierarchy between H60 and H4. Additionally, H60 became predominant when antigen presentation was limited to the direct pathway. However, when antigen presentation was restricted to the indirect pathway, the expansion of H60-specific CD8 T cells was limited, whereas H4-specific CD8 T cells expanded significantly, suggesting that the temporary immunodominance and eventual subdominance of H60 could be due to their reliance on the direct antigen presentation pathway. These results enhance our understanding of the immunodominance phenomenon following allogeneic tissue transplantation.

  6. Non-major histocompatibility complex-restricted cytotoxic activity of blood mononuclear cells stimulated with secreted mycobacterial proteins and other mycobacterial antigens

    DEFF Research Database (Denmark)

    Ravn, P; Pedersen, B K

    1994-01-01

    Several observations indicate that non-major histocompatibility complex (MHC)-restricted cytotoxicity, mediated for example by natural killer cells and lymphokine-activated killer cells, may serve as an important antimicrobial defense mechanism. The purpose of the present study was to investigate...... the influences of different mycobacterial antigens on non-MHC-restricted cytotoxicity and further to investigate the ways by which various lymphocyte subpopulations contribute to the development of this cytotoxicity. Non-MHC-restricted cytotoxicity was induced following stimulation of mononuclear.