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Sample records for cell lysate antigen

  1. Incorporation of antigens from whole cell lysates and purified virions from MP12 into fluorescence microsphere immunoassays for the detection of antibodies against Rift Valley fever virus

    Science.gov (United States)

    Background: The purpose of this study was the development of multiplex fluorescence microsphere immunoassay (FMIA) for the detection of Rift Valley fever virus (RVFV) IgG and IgM antibodies by incorporation of antigens from whole cell lysates and purified virions from MP12. Methods and Findings: Vir...

  2. Autologous Dendritic Cells Pulsed with Allogeneic Tumor Cell Lysate in Mesothelioma: From Mouse to Human.

    Science.gov (United States)

    Aerts, Joachim G J V; de Goeje, Pauline L; Cornelissen, Robin; Kaijen-Lambers, Margaretha E H; Bezemer, Koen; van der Leest, Cor H; Mahaweni, Niken M; Kunert, André; Eskens, Ferry A L M; Waasdorp, Cynthia; Braakman, Eric; van der Holt, Bronno; Vulto, Arnold G; Hendriks, Rudi W; Hegmans, Joost P J J; Hoogsteden, Henk C

    2018-02-15

    Purpose: Mesothelioma has been regarded as a nonimmunogenic tumor, which is also shown by the low response rates to treatments targeting the PD-1/PD-L1 axis. Previously, we demonstrated that autologous tumor lysate-pulsed dendritic cell (DC) immunotherapy increased T-cell response toward malignant mesothelioma. However, the use of autologous tumor material hampers implementation in large clinical trials, which might be overcome by using allogeneic tumor cell lines as tumor antigen source. The purpose of this study was to investigate whether allogeneic lysate-pulsed DC immunotherapy is effective in mice and safe in humans. Experimental Design: First, in two murine mesothelioma models, mice were treated with autologous DCs pulsed with either autologous or allogeneic tumor lysate or injected with PBS (negative control). Survival and tumor-directed T-cell responses of these mice were monitored. Results were taken forward in a first-in-human clinical trial, in which 9 patients were treated with 10, 25, or 50 million DCs per vaccination. DC vaccination consisted of autologous monocyte-derived DCs pulsed with tumor lysate from five mesothelioma cell lines. Results: In mice, allogeneic lysate-pulsed DC immunotherapy induced tumor-specific T cells and led to an increased survival, to a similar extent as DC immunotherapy with autologous tumor lysate. In the first-in-human clinical trial, no dose-limiting toxicities were established and radiographic responses were observed. Median PFS was 8.8 months [95% confidence interval (CI), 4.1-20.3] and median OS not reached (median follow-up = 22.8 months). Conclusions: DC immunotherapy with allogeneic tumor lysate is effective in mice and safe and feasible in humans. Clin Cancer Res; 24(4); 766-76. ©2017 AACR . ©2017 American Association for Cancer Research.

  3. FRET microscopy autologous tumor lysate processing in mature dendritic cell vaccine therapy

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    Ridolfi Ruggero

    2010-06-01

    Full Text Available Abstract Background Antigen processing by dendritic cells (DC exposed to specific stimuli has been well characterized in biological studies. Nonetheless, the question of whether autologous whole tumor lysates (as used in clinical trials are similarly processed by these cells has not yet been resolved. Methods In this study, we examined the transfer of peptides from whole tumor lysates to major histocompatibility complex class II molecules (MHC II in mature dendritic cells (mDC from a patient with advanced melanoma. Tumor antigenic peptides-MHC II proximity was revealed by Förster Resonance Energy Transfer (FRET measurements, which effectively extends the application of fluorescence microscopy to the molecular level ( Results We detected significant energy transfer between donor and acceptor-labelled antibodies against HLA-DR at the membrane surface of mDC. FRET data indicated that fluorescent peptide-loaded MHC II molecules start to accumulate on mDC membranes at 16 hr from the maturation stimulus, steeply increasing at 22 hr with sustained higher FRET detected up to 46 hr. Conclusions The results obtained imply that the patient mDC correctly processed the tumor specific antigens and their display on the mDC surface may be effective for several days. These observations support the rationale for immunogenic efficacy of autologous tumor lysates.

  4. Immunological Characterization of Whole Tumour Lysate-Loaded Dendritic Cells for Cancer Immunotherapy.

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    Veronica Rainone

    Full Text Available Dendritic cells play a key role as initiators of T-cell responses, and even if tumour antigen-loaded dendritic cells can induce anti-tumour responses, their efficacy has been questioned, suggesting a need to enhance immunization strategies.We focused on the characterization of bone marrow-derived dendritic cells pulsed with whole tumour lysate (TAA-DC, as a source of known and unknown antigens, in a mouse model of breast cancer (MMTV-Ras. Dendritic cells were evaluated for antigen uptake and for the expression of MHC class I/II and costimulatory molecules and markers associated with maturation.Results showed that antigen-loaded dendritic cells are characterized by a phenotypically semi-mature/mature profile and by the upregulation of genes involved in antigen presentation and T-cell priming. Activated dendritic cells stimulated T-cell proliferation and induced the production of high concentrations of IL-12p70 and IFN-γ but only low levels of IL-10, indicating their ability to elicit a TH1-immune response. Furthermore, administration of Antigen loaded-Dendritic Cells in MMTV-Ras mice evoked a strong anti-tumour response in vivo as demonstrated by a general activation of immunocompetent cells and the release of TH1 cytokines.Data herein could be useful in the design of antitumoral DC-based therapies, showing a specific activation of immune system against breast cancer.

  5. Tumour cell lysate-loaded dendritic cell vaccine induces biochemical and memory immune response in castration-resistant prostate cancer patients.

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    Reyes, D; Salazar, L; Espinoza, E; Pereda, C; Castellón, E; Valdevenito, R; Huidobro, C; Inés Becker, M; Lladser, A; López, M N; Salazar-Onfray, F

    2013-09-17

    Recently, we produced a tumour antigen-presenting cells (TAPCells) vaccine using a melanoma cell lysate, called TRIMEL, as an antigen source and an activation factor. Tumour antigen-presenting cells induced immunological responses and increased melanoma patient survival. Herein, we investigated the effect of TAPCells loaded with prostate cancer cell lysates (PCCL) as an antigen source, and TRIMEL as a dendritic cell (DC) activation factor; which were co-injected with the Concholepas concholepas haemocyanin (CCH) as an adjuvant on castration-resistant prostate cancer (CRPC) patients. The lysate mix capacity, for inducing T-cell activation, was analysed by flow cytometry and Elispot. Delayed-type hypersensitivity (DTH) reaction against PCCL, frequency of CD8(+) memory T cells (Tm) in blood and prostate-specific antigen (PSA) levels in serum were measured in treated patients. The lysate mix induced functional mature DCs that were capable of activating PCCL-specific T cells. No relevant adverse reactions were observed. Six out of 14 patients showed a significant decrease in levels of PSA. DTH(+) patients showed a prolonged PSA doubling-time after treatment. Expansion of functional central and effector CD8(+) Tm were detected. Treatment of CRPC patients with lysate-loaded TAPCells and CCH as an adjuvant is safe: generating biochemical and memory immune responses. However, the limited number of cases requires confirmation in a phase II clinical trial.

  6. Clinical Benefit of Allogeneic Melanoma Cell Lysate-Pulsed Autologous Dendritic Cell Vaccine in MAGE-Positive Colorectal Cancer Patients

    DEFF Research Database (Denmark)

    Toh, Han Chong; Wang, Who-Whong; Chia, Whay Kuang

    2009-01-01

    PURPOSE: We evaluated the clinical benefit of an allogeneic melanoma cell lysate (MCL)-pulsed autologous dendritic cell (DC) vaccine in advanced colorectal cancer patients expressing at least one of six MAGE-A antigens overexpressed by the cell line source of the lysate. EXPERIMENTAL DESIGN: DCs...... were cultured from peripheral blood mononuclear cells (PBMC), pulsed with the allogeneic MCL, and matured using cytokines that achieved high CD83- and CCR7-expressing DCs. Each patient received up to 10 intradermal vaccinations (3-5 x 10(6) cells per dose) at biweekly intervals. RESULTS: Twenty...... patients received a total of 161 vaccinations. Treatment was well tolerated and quality of life measurements did not vary much across time. One patient experienced partial response [5%; 95% confidence interval (CI), 1-24%] and seven achieved stable disease (35%; 95% CI, 18-57%), one of whom also achieved...

  7. Murine Dendritic Cells Pulsed with Whole Tumor Lysates Mediate Potent Antitumor Immune Responses in vitro and in vivo

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    Fields, R. C.; Shimizu, K.; Mule, J. J.

    1998-08-01

    The highly efficient nature of dendritic cells (DC) as antigen-presenting cells raises the possibility of uncovering in tumor-bearing hosts very low levels of T cell reactivity to poorly immunogenic tumors that are virtually undetectable by other means. Here, we demonstrate the in vitro and in vivo capacities of murine bone marrow-derived, cytokine-driven DC to elicit potent and specific anti-tumor responses when pulsed with whole tumor lysates. Stimulation of naive spleen-derived T cells by tumor lysate-pulsed DC generated tumor-specific proliferative cytokine release and cytolytic reactivities in vitro. In addition, in two separate strains of mice with histologically distinct tumors, s.c. injections of DC pulsed with whole tumor lysates effectively primed these animals to reject subsequent lethal challenges with viable parental tumor cells and, important to note, also mediated significant reductions in the number of metastases established in the lungs. Tumor rejection depended on host-derived CD8+ T cells and, to a lesser extent, CD4+ T cells. Spleens from mice that had rejected their tumors contained specific precursor cytotoxic T lymphocytes. The use of whole tumor lysates as a source of tumor-associated antigen(s) for pulsing of DC circumvents several limitations encountered with other methods as well as provides certain distinct advantages, which are discussed. These data serve as rationale for our recent initiation of a phase I clinical trial of immunization with autologous tumor lysate-pulsed DC in adult and pediatric cancer patients.

  8. Vaccination with melanoma lysate-pulsed dendritic cells, of patients with advanced colorectal carcinoma: report from a phase I study

    DEFF Research Database (Denmark)

    Burgdorf, S K; Fischer, A; Claesson, M H

    2006-01-01

    Immune therapy have shown new and exciting perspectives for cancer treatment. Aim of our study was to evaluate toxicity and possible adverse effects from vaccination of patients with advanced colorectal cancer with autologous dendritic cells (DC) pulsed with lysate from a newly developed melanoma...... cell line, DDM-1.13. Six patients were enrolled in the phase I trial. Autologous DCs were generated in vitro from peripheral blood monocytes in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). DCs were pulsed with melanoma cell lysate from a cloned...... and selected melanoma cell line enriched in expression of MAGE-A antigens and deficient in expression of melanoma differentiation antigens: tyrosinase, MART-1 and gp100. Vaccinations were administered intradermally on the proximal thigh with a total of five given vaccines at 2 weeks intervals. Each vaccine...

  9. Intradermal immunization with combined baculovirus and tumor cell lysate induces effective antitumor immunity in mice.

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    Kawahara, Mamoru; Takaku, Hiroshi

    2013-12-01

    Although tumor lysate contains all the potential helper and killer epitopes capable of stimulating T cells, it is difficult to use as a cancer vaccine because it suppresses dendritic cell (DC) function. We report that wild-type baculovirus possesses an adjuvant effect to improve the immunogenicity of tumor lysate. When mice were administered CT26 tumor cell lysate combined with baculovirus intradermally, antitumor immunity was induced and rejection of CT26 tumor growth was observed in 40% of the immunized mice. In contrast, such antitumor immunity was not elicited in mice inoculated with tumor cell lysate or baculovirus alone. In tumor-bearing mice, which had previously received the combined baculovirus and tumor lysate vaccine, the established tumors were completely eradicated by administering a booster dose of the combined vaccine. This antitumor effect was attributed to tumor-specific T cell immunity mediated primarily by CD8⁺ T cells. Baculovirus also strongly activated DCs loaded with tumor lysate. Increased interleukin (IL)-6 and IL-12p70 production were also observed in DCs co-cultured with tumor cell lysate and baculovirus. Our study demonstrates that combined baculovirus and tumor lysate vaccine can effectively stimulate DCs to induce acquired antitumor immunity.

  10. Effect of platelet lysate on human cells involved in different phases of wound healing.

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    Barsotti, Maria Chiara; Chiara Barsotti, Maria; Losi, Paola; Briganti, Enrica; Sanguinetti, Elena; Magera, Angela; Al Kayal, Tamer; Feriani, Roberto; Di Stefano, Rossella; Soldani, Giorgio

    2013-01-01

    Platelets are rich in mediators able to positively affect cell activity in wound healing. Aim of this study was to characterize the effect of different concentrations of human pooled allogeneic platelet lysate on human cells involved in the different phases of wound healing (inflammatory phase, angiogenesis, extracellular matrix secretion and epithelialization). Platelet lysate effect was studied on endothelial cells, monocytes, fibroblasts and keratinocytes, in terms of viability and proliferation, migration, angiogenesis, tissue repair pathway activation (ERK1/2) and inflammatory response evaluation (NFκB). Results were compared both with basal medium and with a positive control containing serum and growth factors. Platelet lysate induced viability and proliferation at the highest concentrations tested (10% and 20% v/v). Whereas both platelet lysate concentrations increased cell migration, only 20% platelet lysate was able to significantly promote angiogenic activity (phealing.

  11. Effect of platelet lysate on human cells involved in different phases of wound healing.

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    Maria Chiara Barsotti

    Full Text Available BACKGROUND: Platelets are rich in mediators able to positively affect cell activity in wound healing. Aim of this study was to characterize the effect of different concentrations of human pooled allogeneic platelet lysate on human cells involved in the different phases of wound healing (inflammatory phase, angiogenesis, extracellular matrix secretion and epithelialization. METHODOLOGY/PRINCIPAL FINDINGS: Platelet lysate effect was studied on endothelial cells, monocytes, fibroblasts and keratinocytes, in terms of viability and proliferation, migration, angiogenesis, tissue repair pathway activation (ERK1/2 and inflammatory response evaluation (NFκB. Results were compared both with basal medium and with a positive control containing serum and growth factors. Platelet lysate induced viability and proliferation at the highest concentrations tested (10% and 20% v/v. Whereas both platelet lysate concentrations increased cell migration, only 20% platelet lysate was able to significantly promote angiogenic activity (p<0.05 vs. control, comparably to the positive control. Both platelet lysate concentrations activated important inflammatory pathways such as ERK1/2 and NFκB with the same early kinetics, whereas the effect was different for later time-points. CONCLUSION/SIGNIFICANCE: These data suggest the possibility of using allogeneic platelet lysate as both an alternative to growth factors commonly used for cell culture and as a tool for clinical regenerative application for wound healing.

  12. Enhanced target-specific signal detection using an Escherichia coli lysate in multiplex microbead immunoassays with E. coli-derived recombinant antigens.

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    Crestani, Sandra; Leitolis, Amanda; Lima, Lucianna Freitas Oliveira; Krieger, Marco A; Foti, Leonardo

    2016-08-01

    Diverse techniques have been developed to analyze antibody-mediated responses to infections. However, the most common tests, i.e., enzyme-linked immunosorbent assays, require separate reactions for each antigen and consequently necessitate large sample volumes. Luminex technology allows the detection of multiple antibodies in a single experiment, but nonspecific binding can impair the results. Therefore, we examined the use of Escherichia coli lysates to reduce nonspecific binding and improve the results of liquid microarrays based on Luminex technology. Anti-bacteria antibodies were detected in human serum samples, as evidenced by high median fluorescence intensity (MFI) in assays performed with paramagnetic microspheres coupled with E. coli lysates. Moreover, the addition of an E. coli lysate as a blocker reduced the nonspecific binding of antigens produced by E. coli in a concentration-dependent manner. Tris-HCl reduced MFI values in negative samples, but did not affect MFI for positive samples. For microspheres coupled with different antigens, an E. coli lysate blocker significantly improved the fluorescence signals from positive samples. The addition of Tris-HCl and the E. coli lysate induced antigen-specific differences in MFI. This combination of the E. coli lysate blocker and Tris-HCl yielded a statistically significant improvement in MFI in the assays for Chagas disease and hepatitis C virus samples. However, for the Treponema pallidum p47 antigen improvement in MFI was only observed for the preparation with the E. coli blocker at a concentration of 3%. In conclusion, the addition of an E. coli lysate and Tris-HCl to the microarray assay reduced the nonspecific binding of human anti-bacteria antibodies and, therefore, increased the specific MFI. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Middle T antigen-transformed endothelial cells exhibit an increased activity of nitric oxide synthase

    OpenAIRE

    1995-01-01

    Endothelioma cell lines transformed by polyoma virus middle T antigen (mTa) cause cavernous hemangiomas in syngeneic mice by recruitment of host cells. The production of nitric oxide (NO), as measured by nitrite and citrulline production, was significantly higher in mTa-transformed endothelial cells in comparison with nontransformed control cells. The maximal activity of NO synthase (NOS) was about 200-fold higher in cell lysates from the tEnd.1 endothelioma cell line than in lysates from non...

  14. Freeze-thaw lysates of Plasmodium falciparum-infected red blood cells induce differentiation of functionally competent regulatory T cells from memory T cells.

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    Finney, Olivia C; Lawrence, Emma; Gray, Alice P; Njie, Madi; Riley, Eleanor M; Walther, Michael

    2012-07-01

    In addition to naturally occurring regulatory T (nTreg) cells derived from the thymus, functionally competent Treg cells can be induced in vitro from peripheral blood lymphocytes in response to TCR stimulation with cytokine costimulation. Using these artificial stimulation conditions, both naïve as well as memory CD4(+) T cells can be converted into induced Treg (iTreg) cells, but the cellular origin of such iTreg cells in vivo or in response to more physiologic stimulation with pathogen-derived antigens is less clear. Here, we demonstrate that a freeze/thaw lysate of Plasmodium falciparum schizont extract (PfSE) can induce functionally competent Treg cells from peripheral lymphocytes in a time- and dose-dependent manner without the addition of exogenous costimulatory factors. The PfSE-mediated induction of Treg cells required the presence of nTreg cells in the starting culture. Further experiments mixing either memory or naïve T cells with antigen presenting cells and CFSE-labeled Treg cells identified CD4(+) CD45RO(+) CD25(-) memory T cells rather than Treg cells as the primary source of PfSE-induced Treg cells. Taken together, these data suggest that in the presence of nTreg cells, PfSE induces memory T cells to convert into iTreg cells that subsequently expand alongside PfSE-induced effector T cells. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Vaccination with Toxoplasma lysate antigen and CpG oligodeoxynucleotides: comparison of immune responses in intranasal versus intramuscular administrations.

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    EL-Malky, Mohamed A; Al-Harthi, Saeed A; Mohamed, Raafat T; EL Bali, Mohamed A; Saudy, Niveen S

    2014-06-01

    Toxoplasma gondii (T. gondii) is one of the most successful intracellular protozoan parasites on earth and highly prevalent in most warm-blooded vertebrates. There are no drugs that target the chronic cyst stage of this infection; therefore, development of an effective vaccine would be an important advance in disease control. Oligodeoxynucleotides (ODN) which contain immunostimulatory CG motifs (CpG ODN) can promote T-helper 1 (Th1) responses, an adjuvant activity that is desirable for vaccination against intracellular pathogen. In this study, we compare the immune responses of Toxoplasma susceptible C57BL/6 mice following intranasal and intramuscular vaccination with Toxoplasma lysate antigen (TLA) with or without CpG ODN as adjuvant. Immunized and control non-immunized mice were challenged with 85 cyst of the moderately virulent Beverley strain of T. gondii. Intranasal vaccination gave significantly a higher protection compared to other groups as indicated by prolonged survival and significantly reduced brain cyst burden (P intramuscular vaccination enhanced humoral immunity towards a type Th1 pattern characterized by a significant increase of specific IgG and Ig2a. Our results suggest that intranasal administration of CpG/TLA would provide a stable, pronounced, and effective vaccine against toxoplasmosis through stimulation of Th1 cellular immunity and mucosal IgA.

  16. Determination of Immunogenic Relevant Antigens in the Excretory-Secretory (ES Products and the Lysates of Ascaridia galli Larvae

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    S Saffi

    2008-04-01

    Full Text Available Background: Ascaridia galli, the largest nematode of small intestine of birds, especially the native poultry, may give rise to serious illness, pathological defects and economical losses even in modern poultry production systems. Although various measures have been undertaken to vaccinate poultry against A.galli, no satisfactory results were obtained so far. However, there is no report on the efficacy of excretory-secretory (ES proteins of A.galli larvae in immunization of poultry. Thus, the aim of the present research project was based on the use of the ES products of the larvae, in order to find the protective anti­gens.Methods: Five hundred native poultry were autopsied and adult A.galli was removed form their intestines. The eggs were harvested form the uterus of female worms and cultured at 25 ˚C in water containing 0.1 N sulphuric acid for almost a fort­night. The larvae were then freed mechanically and kept in Earl's salt solution for a few days. The supernatant solution of alive larvae containing the ES products of the larvae, as well as the sonicated alive and dead larvae, was analyzed by SDS-PAGE.Result: Many protein fractions of 15 kDa up to 200 kDa were demonstrated in lysate of these larvae. Using the serum of a hen, infected with a high numbers of A.galli, an immunogenic antigen was identified between 55 kDa to 72 kDa by Western blotting procedure.Conclusion: Finding the protein band between 55 and 72 kDa can be promising for preparation of vaccine, though more investigations are needed to prove the protective ability of this antigen.

  17. A simple, inexpensive method for preparing cell lysates suitable for downstream reverse transcription quantitative PCR.

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    Shatzkes, Kenneth; Teferedegne, Belete; Murata, Haruhiko

    2014-04-11

    Sample nucleic acid purification can often be rate-limiting for conventional quantitative PCR (qPCR) workflows. We recently developed high-throughput virus microneutralization assays using an endpoint assessment approach based on reverse transcription qPCR (RT-qPCR). The need for cumbersome RNA purification is circumvented in our assays by making use of a commercial reagent that can easily generate crude cell lysates amenable to direct analysis by one-step RT-qPCR. In the present study, we demonstrate that a simple buffer containing a non-ionic detergent can serve as an inexpensive alternative to commercially available reagents for the purpose of generating RT-qPCR-ready cell lysates from MDCK cells infected with influenza virus. We have found that addition of exogenous RNase inhibitor as a buffer component is not essential in order to maintain RNA integrity, even following stress at 37 °C incubation for 1-2 hours, in cell-lysate samples either freshly prepared or previously stored frozen at -80 °C.

  18. Optimizing parameters for clinical-scale production of high IL-12 secreting dendritic cells pulsed with oxidized whole tumor cell lysate

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    Chiang Cheryl L-L

    2011-11-01

    Full Text Available Abstract Background Dendritic cells (DCs are the most potent antigen-presenting cell population for activating tumor-specific T cells. Due to the wide range of methods for generating DCs, there is no common protocol or defined set of criteria to validate the immunogenicity and function of DC vaccines. Methods Monocyte-derived DCs were generated during 4 days of culture with recombinant granulocyte-macrophage colony stimulating factor and interleukin-4, and pulsed with tumor lysate produced by hypochlorous acid oxidation of tumor cells. Different culture parameters for clinical-scale DC preparation were investigated, including: 1 culture media; 2 culture surface; 3 duration of activating DCs with lipopolysaccharide (LPS and interferon (IFN-gamma; 4 method of DC harvest; and 5 cryomedia and final DC product formulation. Results DCs cultured in CellGenix DC media containing 2% human AB serum expressed higher levels of maturation markers following lysate-loading and maturation compared to culturing with serum-free CellGenix DC media or AIM-V media, or 2% AB serum supplemented AIM-V media. Nunclon™Δ surface, but not Corning® tissue-culture treated surface and Corning® ultra-low attachment surface, were suitable for generating an optimal DC phenotype. Recombinant trypsin resulted in reduced major histocompatibility complex (MHC Class I and II expression on mature lysate-loaded DCs, however presentation of MHC Class I peptides by DCs was not impaired and cell viability was higher compared to cell scraping. Preservation of DCs with an infusible cryomedia containing Plasma-Lyte A, dextrose, sodium chloride injection, human serum albumin, and DMSO yielded higher cell viability compared to using human AB serum containing 10% DMSO. Finally, activating DCs for 16 hours with LPS and IFN-γ stimulated robust mixed leukocyte reactions (MLRs, and high IL-12p70 production in vitro that continued for 24 hours after the cryopreserved DCs were thawed and

  19. Leishmania (L.) amazonensis peptidase activities inside the living cells and in their lysates.

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    Caroselli, Elide E; Assis, Diego M; Barbiéri, Clara L; Júdice, Wagner A S; Juliano, Maria A; Gazarini, Marcos L; Juliano, Luiz

    2012-08-01

    In this study we investigated the peptidase activity in Leishmania (L.) amazonensis live amastigote by confocal microscopy using peptidyl-MCA as substrates, the hydrolysis of which releases the MCA fluorophore inside the cells. Cell pre-treatment with peptidase inhibitors indicated the presence of cysteine and serine peptidases. It was noteworthy that Leishmania amastigotes incorporate only substrates (Z-FR-MCA, Z-RR-MCA) or inhibitors (E64, TLCK) containing positively charged groups. The peptidase activities in the supernatants of amastigotes and promastigotes lysates were also evaluated with the same peptidyl-MCA substrates and inhibitors in the pH range 4.5-9.0. The effects of temperature and different salts were also included in this study. The hydrolytic activities of supernatants on Z-FR-MCA clearly indicate the presence of different cysteine peptidases that adapted to work in different environment conditions. Intact Leishmania cells incorporated Z-RR-MCA, the hydrolysis of which was inhibited only by TLCK indicating the presence of at least one serine peptidase. The pH profile of Z-RR-MCA hydrolysis by amastigotes and promastigotes lysate supernatants, and the hydrolysis time course of the FRET peptide Abz-AGRRRAQ-EDDnp at RA bond, followed by removal of the two C-termini R to yield Abz-AGR-OH that is a unique characteristic of oligopeptidase B, indicate its presence in the parasite. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Naegleria fowleri lysate induces strong cytopathic effects and pro-inflammatory cytokine release in rat microglial cells.

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    Lee, Yang-Jin; Park, Chang-Eun; Kim, Jong-Hyun; Sohn, Hae-Jin; Lee, Jinyoung; Jung, Suk-Yul; Shin, Ho-Joon

    2011-09-01

    Naegleria fowleri, a ubiquitous free-living ameba, causes fatal primary amebic meningoencephalitis in humans. N. fowleri trophozoites are known to induce cytopathic changes upon contact with microglial cells, including necrotic and apoptotic cell death and pro-inflammatory cytokine release. In this study, we treated rat microglial cells with amebic lysate to probe contact-independent mechanisms for cytotoxicity, determining through a combination of light microscopy and scanning and transmission electron microscopy whether N. fowleri lysate could effect on both necrosis and apoptosis on microglia in a time- as well as dose-dependent fashion. A (51)Cr release assay demonstrated pronounced lysate induction of cytotoxicity (71.5%) toward microglial cells by 24 hr after its addition to cultures. In an assay of pro-inflammatory cytokine release, microglial cells treated with N. fowleri lysate produced TNF-α, IL-6, and IL-1β, though generation of the former 2 cytokines was reduced with time, and that of the last increased throughout the experimental period. In summary, N. fowleri lysate exerted strong cytopathic effects on microglial cells, and elicited pro-inflammatory cytokine release as a primary immune response.

  1. Stimulation with lysates of Aspergillus terreus, Candida krusei and Rhizopus oryzae maximizes cross-reactivity of anti-fungal T cells.

    Science.gov (United States)

    Deo, Shivashni S; Virassamy, Balaji; Halliday, Catriona; Clancy, Leighton; Chen, Sharon; Meyer, Wieland; Sorrell, Tania C; Gottlieb, David J

    2016-01-01

    Invasive fungal diseases caused by filamentous fungi and yeasts are significant causes of morbidity and mortality in immunosuppressed hematology patients. We previously published a method to expand Aspergillus fumigatus-specific T cells for clinical cell therapy. In the present study, we investigated expansion of T cells specific for other fungal pathogens and creation of a broadly reactive panfungal T-cell product. Fungal strains selected were those frequently observed in the clinical hematology setting and included Aspergillus, Candida, Fusarium, Rhizopus and Lomentospora/Scedosporium. Four T-cell cultures specific to each fungus were established. We selected lysates of Aspergillus terreus, Candida krusei and Rhizopus oryzae to expand panfungal T cells. Allelic restriction of anti-fungal activity was determined through the use of specific major histocompatibility complex class II-blocking antibodies. Individual T-cell cultures specific to each fungus could be expanded in vitro, generating predominantly CD4(+) T cells of which 8% to 20% were fungus-specific. We successfully expanded panfungal T cells from the peripheral blood (n = 8) and granulocyte-colony-stimulating factor-primed stem cell products (n = 3) of normal donors by using a combination of lysates from Aspergillus terreus, Candida krusei and Rhizopus oryzae. Anti-fungal activity was mediated through human leukocyte antigen (HLA)-DR alleles and was maintained when antigen-presenting cells from partially HLA-DRB1-matched donors were used to stimulate T cells. We demonstrate a method to manufacture panfungal T-cell products with specificity against a range of clinical fungal pathogens by use of the blood and stem cells of healthy donors as the starting material. The safety and efficacy of these products will need to be tested clinically. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  2. A similar in vitro and in cell lysate folding intermediate for the FF domain.

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    Latham, Michael P; Kay, Lewis E

    2014-09-23

    Understanding the mechanisms by which proteins fold into their three-dimensional structures, including a description of the intermediates that are formed during the folding process, remains a goal of protein science. Most studies are performed under carefully controlled conditions in which the folding reaction is monitored in a buffer solution that is far from the natural milieu of the cell. Here, we have used (13)C and (1)H relaxation dispersion NMR spectroscopy to study folding of the FF domain in both Escherichia coli and Saccharomyces cerevisiae cellular lysates. We find that a conformationally excited state is populated in both lysates, which is very similar in structure to a folding intermediate observed in previous studies in buffer, with the kinetics and thermodynamics of the interconversion between native and intermediate conformers somewhat changed. The results point to the importance of extending folding studies beyond the test tube yet emphasize that insights can be obtained through careful experiments recorded in controlled buffer solutions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Immune responses in patients with metastatic renal cell carcinoma treated with dendritic cells pulsed with tumor lysate

    DEFF Research Database (Denmark)

    Soleimani, A; Berntsen, A; Svane, I M

    2009-01-01

    Patients with metastatic renal cell carcinoma (mRCC) have a limited life expectancy but still a subset of these patients develop immune and clinical responses after immunotherapy including dendritic cell (DC) vaccination. In a recently published phase I/II trials, fourteen HLA-A2 negative patients...... with progressive mRCC were vaccinated with autologous DC pulsed with allogeneic tumour lysate. Low-dose IL-2 administered subcutaneously was given concomitantly. In this study, we analysed lysate specific proliferation of PBMCs from these patients together with the TH1/TH2 balance of the responding T cells. Also......, serum concentrations of IL-10, IL-12, IL-15, IL-17 and IL-18 from these patients and additional thirteen HLA-A2 positive mRCC patients treated with autologous DC pulsed with survivin and telomerase peptides were analysed during vaccination to identify systemic immune responses and potential response...

  4. Surface-enhanced Raman spectroscopy of cell lysates mixed with silver nanoparticles for tumor classification

    Directory of Open Access Journals (Sweden)

    Mohamed Hassoun

    2017-06-01

    Full Text Available The throughput of spontaneous Raman spectroscopy for cell identification applications is limited to the range of one cell per second because of the relatively low sensitivity. Surface-enhanced Raman scattering (SERS is a widespread way to amplify the intensity of Raman signals by several orders of magnitude and, consequently, to improve the sensitivity and throughput. SERS protocols using immuno-functionalized nanoparticles turned out to be challenging for cell identification because they require complex preparation procedures. Here, a new SERS strategy is presented for cell classification using non-functionalized silver nanoparticles and potassium chloride to induce aggregation. To demonstrate the principle, cell lysates were prepared by ultrasonication that disrupts the cell membrane and enables interaction of released cellular biomolecules to nanoparticles. This approach was applied to distinguish four cell lines – Capan-1, HepG2, Sk-Hep1 and MCF-7 – using SERS at 785 nm excitation. Six independent batches were prepared per cell line to check the reproducibility. Principal component analysis was applied for data reduction and assessment of spectral variations that were assigned to proteins, nucleotides and carbohydrates. Four principal components were selected as input for classification models based on support vector machines. Leave-three-batches-out cross validation recognized four cell lines with sensitivities, specificities and accuracies above 96%. We conclude that this reproducible and specific SERS approach offers prospects for cell identification using easily preparable silver nanoparticles.

  5. Heat inactivation of a norovirus surrogate in cell culture lysate, abalone meat, and abalone viscera.

    Science.gov (United States)

    Park, Shin Young; Bae, San-Cheong; Ha, Sang-Do

    2015-03-01

    The current study examined the effects of temperature and heat treatment duration on murine norovirus-1 (MNV-1) from both viral cell culture lysate (7-8 log10 PFU) and experimentally contaminated abalone meat and viscera (5-6 log10 PFU) as a model of human norovirus (NoV). MNV-1 titers in cell culture lysate, abalone meat, and abalone viscera were gradually reduced to 1.93-4.55, 1.79-3.00, and 2.26-3.26 log10 PFU/ml, respectively, after treatment at 70 °C for 1-10 min. Treatment at 85 °C for 1-5 min gradually reduced MNV-1 titers in abalone meat to 2.71-4.15 log10 PFU/ml. MNV-1 titers in abalone viscera were gradually reduced to 2.91-3.46 log10 PFU/ml after treatment at 85 °C for 1-3 min. No significant difference (P > 0.05) was found in MNV-1 titers in the abalone meat and viscera among treatment groups (70 °C for 5 min, 70 °C for 3 min, and 85 °C for 1 min). Complete inactivation of MNV-1 in cell culture lysate was determined at 85 °C for ≥1 min and 100 °C for ≥0.5 min. Complete inactivation of MNV-1 in abalone was determined at 100 °C for ≥0.5 min for meat, and 85 °C for 5 min and 100 °C for ≥0.5 min for viscera. At treatments at 70 °C, the Td-values (3 log reduction time) were significantly lower (P 0.05) between abalone meat (1.78) and abalone viscera (1.33) at treatments at 85 °C. This study suggests that 100 °C for ≥0.5 min could potentially be used to inactivate NoV in molluscan shellfishes, including viscera.

  6. Feasibility and Efficiency of Human Bone Marrow Stromal Cell Culture with Allogeneic Platelet Lysate-Supplementation for Cell Therapy against Stroke

    Directory of Open Access Journals (Sweden)

    Chengbo Tan

    2016-01-01

    Full Text Available Currently, there is increasing interest in human bone marrow stromal cells (hBMSCs as regeneration therapy against cerebral stroke. The aim of the present study was to evaluate the feasibility and validity of hBMSC cultures with allogeneic platelet lysates (PLs. Platelet concentrates (PC were harvested from healthy volunteers and made into single donor-derived PL (sPL. The PL mixtures (mPL were made from three different sPL. Some growth factors and platelet cell surface antigens were detected by enzyme-linked immunosorbent assay (ELISA. The hBMSCs cultured with 10% PL were analyzed for their proliferative potential, surface markers, and karyotypes. The cells were incubated with superparamagnetic iron oxide (SPIO agents and injected into a pig brain. MRI and histological analysis were performed. Consequently, nine lots of sPL and three mPL were prepared. ELISA analysis showed that PL contained adequate growth factors and a particle of platelet surface antigens. Cell proliferation capacity of PLs was equivalent to or higher than that of fetal calf serum (FCS. No contradiction in cell surface markers and no chromosomal aberrations were found. The MRI detected the distribution of SPIO-labeled hBMSCs in the pig brain. In summary, the hBMSCs cultured with allogeneic PL are suitable for cell therapy against stroke.

  7. Effect of radiation on the expression of tumor-associated antigens of human lung adenocarcinoma cells

    International Nuclear Information System (INIS)

    Hareyama, Masato

    1988-01-01

    We studied the effects of irradiation on the expression of a tumor-associated antigen (YH206 antigen) of cultured human lung adenocarcinoma A549 cells by using enzyme-linked immunosorbent assay (ELISA) and flow cytometry. YH206 antigen is preferentially expressed on adenocarcinoma cells. Irradiation of A549 cells remarkably increased the expression of YH206 antigen on the cell surface and the level of the antigen in the culture supernatant as well as in the cell lysate, whereas it significantly affected the expression of HLA (MHC-class I) antigen on the same cells. The expression of HLA antigen on the cell was also increased after treatment of the cells with interferon-γ. In an additional experiment, cells were stained simultaneously for surface antigens (fluorescein coupled antibodies) and for DNA content (propidium iodide), and then dual parameter measurements were performed by flow cytometry to analyse the relationship between antigen levels and the cell cycle. YH206 antigen and HLA antigen increased more in the S and G 2 /M phases of the cell cycle than in G 0 /G 1 . The expression of YH206 antigen was enhanced in the S and G 2 /M phases by irradiation, whereas the expression of HLA antigen was enhanced in each phase of the cell cycle with irradiation or IFN. These results suggest that irradiation plays a key role in the change of the expression of certain tumor-associated antigens. (author)

  8. Colony Lysate Arrays for Proteomic Profiling of Drug-Tolerant Persisters of Cancer Cell.

    Science.gov (United States)

    Kume, Kohei; Nishizuka, Satoshi S

    2017-09-05

    Functional heterogeneity of cancer cells is one of the key properties to understanding relapse after drug treatment. Hence, clarification is needed with regard to which types of subgroups of cancer cells dominantly contribute to the initiation of relapse. Recently, we established the colony lysate array (CoLA), which is a method that allows comparison of individual colonies at the protein level to assess the initiation of anticancer drug-tolerant persisters (DTPs) based on the reverse-phase protein array (RPPA) system. DTPs grow in various drug concentrations and types showing 2-dimensional growth (∼1 mm) on a flat surface. The size of DTPs are larger than spheroids (∼0.3 mm) in agarose gel, which makes them easy to handle for a number of assays. DTPs provide functional information during the process of their formation, initiating from the origin of a drug-tolerant single cell. Using >2000 DTPs generated from various drugs and doses profiled on the basis of 44 proteins, we demonstrate that the DTPs are clustered on the basis of their proteomic profiles changing in response to drugs and doses. Of interest, nine transcription factors in the DTPs, such as STAT3 and OCT4A, were identified as having decreased or increased levels of proteins in response to gefitinib. Importantly, these results can be obtained only by individual proteomic colony profiling, which may identify alternative therapeutic targets and biomarkers for DTPs that may harbor critical mechanisms for cancer relapse.

  9. Dendritic cells loaded with pancreatic Cancer Stem Cells (CSCs lysates induce antitumor immune killing effect in vitro.

    Directory of Open Access Journals (Sweden)

    Tao Yin

    Full Text Available According to the cancer stem cells (CSCs theory, malignant tumors may be heterogeneous in which a small population of CSCs drive the progression of cancer. Because of their intrinsic abilities, CSCs may survive a variety of treatments and then lead to therapeutic resistance and cancer recurrence. Pancreatic CSCs have been reported to be responsible for the malignant behaviors of pancreatic cancer, including suppression of immune protection. Thus, development of immune strategies to eradicate pancreatic CSCs may be of great value for the treatment of pancreatic cancer. In this study, we enriched pancreatic CSCs by culturing Panc-1 cells under sphere-forming conditions. Panc-1 CSCs expressed low levels of HLA-ABC and CD86, as measured by flow cytometry analysis. We further found that the Panc-1 CSCs modulate immunity by inhibiting lymphocyte proliferation which is promoted by phytohemagglutinin (PHA and anti-CD3 monoclonal antibodies. The monocyte derived dendritic cells (DCs were charged with total lysates generated from Panc-1 CSCs obtained from tumor sphere culturing. After co-culturing with lymphocytes at different ratios, the Panc-1 CSCs lysates modified DC effectively promoted lymphocyte proliferation. The activating efficiency reached 72.4% and 74.7% at the ratios of 1∶10 and 1∶20 with lymphocytes. The activated lymphocytes secreted high levels of INF-γ and IL-2, which are strong antitumor cytokines. Moreover, Panc-1 CSCs lysates modified DC induced significant cytotoxic effects of lymphocytes on Panc-1 CSCs and parental Panc-1 cells, respectively, as shown by lactate dehydrogenase (LDH assay. Our study demonstrates that the development of CSCs-based vaccine is a promising strategy for treating pancreatic cancer.

  10. Identification of Yeast V-ATPase Mutants by Western Blots Analysis of Whole Cell Lysates

    Science.gov (United States)

    Parra-Belky, Karlett

    2002-11-01

    A biochemistry laboratory was designed for an undergraduate course to help students better understand the link between molecular engineering and biochemistry. Students identified unknown yeast strains with high specificity using SDS-PAGE and Western blot analysis of whole cell lysates. This problem-solving exercise is a common application of biochemistry in biotechnology research. Three different strains were used: a wild-type and two mutants for the proton pump vacuolar ATPase (V-ATPase). V-ATPases are multisubunit enzymes and the mutants used were deletion mutants; each lacked one structural gene of the complex. After three, three-hour labs, mutant strains were easily identified by the students and distinguished from wild-type cells analyzing the pattern of SDS-PAGE distribution of proteins. Identifying different subunits of one multimeric protein allowed for discussion of the structure and function of this metabolic enzyme, which captured the interest of the students. The experiment can be adapted to other multimeric protein complexes and shows improvement of the described methodology over previous reports, perhaps because the problem and its solution are representative of the type of techniques currently used in research labs.

  11. Donor age of human platelet lysate affects proliferation and differentiation of mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Michael Lohmann

    Full Text Available The regenerative potential declines upon aging. This might be due to cell-intrinsic changes in stem and progenitor cells or to influences by the microenvironment. Mesenchymal stem cells (MSC raise high hopes in regenerative medicine. They are usually culture expanded in media with fetal calf serum (FCS or other serum supplements such as human platelet lysate (HPL. In this study, we have analyzed the impact of HPL-donor age on culture expansion. 31 single donor derived HPLs (25 to 57 years old were simultaneously compared for culture of MSC. Proliferation of MSC did not reveal a clear association with platelet counts of HPL donors or growth factors concentrations (PDGF-AB, TGF-β1, bFGF, or IGF-1, but it was significantly higher with HPLs from younger donors (45 years. Furthermore, HPLs from older donors increased activity of senescence-associated beta-galactosidase (SA-βgal. HPL-donor age did not affect the fibroblastoid colony-forming unit (CFU-f frequency, immunophenotype or induction of adipogenic differentiation, whereas osteogenic differentiation was significantly lower with HPLs from older donors. Concentrations of various growth factors (PDGF-AB, TGF-β1, bFGF, IGF-1 or hormones (estradiol, parathormone, leptin, 1,25 vitamin D3 were not associated with HPL-donor age or MSC growth. Taken together, our data support the notion that aging is associated with systemic feedback mechanisms acting on stem and progenitor cells, and this is also relevant for serum supplements in cell culture: HPLs derived from younger donors facilitate enhanced expansion and more pronounced osteogenic differentiation.

  12. Rapid and simple purification of elastin-like polypeptides directly from whole cells and cell lysates by organic solvent extraction.

    Science.gov (United States)

    VerHeul, Ross; Sweet, Craig; Thompson, David H

    2018-03-26

    Elastin-like polypeptides (ELP) are a well-known class of proteins that are being increasingly utilized in a variety of biomedical applications, due to their beneficial physicochemical properties. A unifying feature of ELP is their demonstration of a sequence tunable inverse transition temperature (Tt) that enables purification using a simple, straightforward process called inverse transition cycling (ITC). Despite the utility of ITC, the process is inherently limited to ELP with an experimentally accessible Tt. Since the underlying basis for the ELP Tt is related to its high overall hydrophobicity, we anticipated that ELP would be excellent candidates for purification by organic extraction. We report the first method for rapidly purifying ELP directly from whole E. coli cells or clarified lysates using pure organic solvents and solvent mixtures, followed by aqueous back extraction. Our results show that small ELP and a large ELP-fusion protein can be isolated in high yield from whole cells or cell lysates with greater than 95% purity in less than 30 min and with very low levels of LPS and DNA contamination.

  13. Data for high-throughput estimation of specific activities of enzyme/mutants in cell lysates through immunoturbidimetric assay of proteins

    Directory of Open Access Journals (Sweden)

    Yiran Feng

    2017-10-01

    Full Text Available Data in this article are associated with the research article “Highthroughput estimation of specific activities of enzyme/mutants in cell lysates through immunoturbidimetric assay of proteins” (Yang et al., 2017 [1]. This article provided data on how to develop an immunoturbidimetric assay (ITA of enzyme/mutants as proteins in cell lysates in high-throughput (HTP mode together with HTP assay of their activities to derive their specific activities in cell lysates for comparison, with Pseudomonas aeruginosa arylsulfatase (PAAS and Bacillus fastidious uricase (BFU plus their mutants as models. Data were made publicly available for further analyses.

  14. Allogeneic effector/memory Th-1 cells impair FoxP3+ regulatory T lymphocytes and synergize with chaperone-rich cell lysate vaccine to treat leukemia.

    Science.gov (United States)

    Janikashvili, Nona; LaCasse, Collin J; Larmonier, Claire; Trad, Malika; Herrell, Amanda; Bustamante, Sara; Bonnotte, Bernard; Har-Noy, Michael; Larmonier, Nicolas; Katsanis, Emmanuel

    2011-02-03

    Therapeutic strategies combining the induction of effective antitumor immunity with the inhibition of the mechanisms of tumor-induced immunosuppression represent a key objective in cancer immunotherapy. Herein we demonstrate that effector/memory CD4(+) T helper-1 (Th-1) lymphocytes, in addition to polarizing type-1 antitumor immune responses, impair tumor-induced CD4(+)CD25(+)FoxP3(+) regulatory T lymphocyte (Treg) immunosuppressive function in vitro and in vivo. Th-1 cells also inhibit the generation of FoxP3(+) Tregs from naive CD4(+)CD25(-)FoxP3(-) T cells by an interferon-γ-dependent mechanism. In addition, in an aggressive mouse leukemia model (12B1), Th-1 lymphocytes act synergistically with a chaperone-rich cell lysate (CRCL) vaccine, leading to improved survival and long-lasting protection against leukemia. The combination of CRCL as a source of tumor-specific antigens and Th-1 lymphocytes as an adjuvant has the potential to stimulate efficient specific antitumor immunity while restraining Treg-induced suppression.

  15. Combinations of SPR and MS for Characterizations of Native and Recombinant Proteins in Cell Lysates

    DEFF Research Database (Denmark)

    Borch, Jonas; Roepstorff, Peter

    2006-01-01

    of 14-3-3 proteins in order to test their activity. Specific binding of recombinant and native 14-3-3 proteins in complex mixtures to immobilized phosphopeptides and subsequent elution was also tested by SPR-MS. Ammonium sulfate precipitate fractions from lysates of E. coli expressing 14-3-3 protein...

  16. Clinical and Immunological Effects in Patients with Advanced Non-Small Cell Lung-Cancer after Vaccination with Dendritic Cells Exposed to an Allogeneic Tumor Cell Lysate*

    DEFF Research Database (Denmark)

    Engell-Noerregaard, Lotte; Kvistborg, Pia; Zocca, Mai-Britt

    2013-01-01

    Background: We evaluated the clinical and immunological effects of dendritic cell (DC) vaccination of patients with NSCLC. Autologous DCs were pulsed with a MAGE containing allogeneic melanoma cell lysate (MelCancerVac®, Dandrit Biotech, Copenhagen, Denmark). Imiquimod cream, proleukin and celeco......Background: We evaluated the clinical and immunological effects of dendritic cell (DC) vaccination of patients with NSCLC. Autologous DCs were pulsed with a MAGE containing allogeneic melanoma cell lysate (MelCancerVac®, Dandrit Biotech, Copenhagen, Denmark). Imiquimod cream, proleukin...... one patient with progressive disease (PD) showed vaccine-specific re- sponses. Conclusion: This DC-based vaccine trial has indicated a correlation between vaccine-specific immunity and sustained SD. Furthermore, we observed an unexpectedly prolonged survival in some patients, which may indicate de...

  17. Induction of interleukin-8 by Naegleria fowleri lysates requires activation of extracellular signal-regulated kinase in human astroglial cells.

    Science.gov (United States)

    Kim, Jong-Hyun; Sohn, Hae-Jin; Lee, Sang-Hee; Kwon, Daeho; Shin, Ho-Joon

    2012-08-01

    Naegleria fowleri is a pathogenic free-living amoeba which causes primary amoebic meningoencephalitis in humans and experimental animals. To investigate the mechanisms of such inflammatory diseases, potential chemokine gene activation in human astroglial cells was investigated following treatment with N. fowleri lysates. We demonstrated that N. fowleri are potent inducers for the expression of interleukin-8 (IL-8) genes in human astroglial cells which was preceded by activation of extracellular signal-regulated kinase (ERK). In addition, N. fowleri lysates induces the DNA binding activity of activator protein-1 (AP-1), an important transcription factor for IL-8 induction. The specific mitogen-activated protein kinase kinase/ERK inhibitor, U0126, blocks N. fowleri-mediated AP-1 activation and subsequent IL-8 induction. N. fowleri-induced IL-8 expression requires activation of ERK in human astroglial cells. These findings indicate that treatment of N. fowleri on human astroglial cells leads to the activation of AP-1 and subsequent expression of IL-8 which are dependent on ERK activation. These results may help understand the N. fowleri-mediated upregulation of chemokine and cytokine expression in the astroglial cells.

  18. A comparative study of Mono Mac 6 cells, isolated mononuclear cells and Limulus amoebocyte lysate assay in pyrogen testing

    DEFF Research Database (Denmark)

    Moesby, Lise; Jensen, S; Hansen, E W

    1999-01-01

    ) and Staphylococcus aureus was comparable to that of MNC. Aspergillus niger and Candida albicans induced IL-6 in isolated MNC, but not in MM6. The detection limit for Salmonella typhimurium in the MM6 assay was comparable to that of the LAL assay. As expected, S. aureus and C. albicans did not show any LAL activity......Pyrogen induced secretion of interleukin 6 (IL-6) in Mono Mac 6 (MM6) cells was measured. The ability of the MM6 cell culture to detect pyrogens was compared to the Limulus amoebocyte lysate (LAL) test and isolated mononuclear cells (MNC). The detection limit of MM6 for lipopolysaccharide (LPS....... A. niger and Influenza virus showed some activity in the LAL test, but could not be detected by MM6 cells. In conclusion, the MM6 assay is a good supplement to the current pyrogen assays for detection of LPS, S. aureus and S. typhimurium, but the MM6 assay could not detect A. niger, C. albicans...

  19. Mapping of proteomic lysate of a MCF-7 cancer cell line for the identification of potential markers for breast cancer

    Directory of Open Access Journals (Sweden)

    V. E. Shevchenko

    2012-01-01

    Full Text Available Mass spectrometric mapping of proteomic lysate of a MCF-7 cancer cell line was carried out, which identified 153 proteins having molecular weights of 5000 to 630000 Da, a high proportion of which was cytoplasmic and nuclear proteins. The latter accounted for 60 % of their total number whereas the proportion of extracellular and membrane proteins constituted 13 %. After using some selection criteria to analyze the findings, the authors present a list of 31 potential biomarkers and describe 12 promising breast anticancer therapeutic targets.

  20. Donor T cells primed on leukemia lysate-pulsed recipient APCs mediate strong graft-versus-leukemia effects across MHC barriers in full chimeras.

    Science.gov (United States)

    Ghosh, Arnab; Koestner, Wolfgang; Hapke, Martin; Schlaphoff, Verena; Länger, Florian; Baumann, Rolf; Koenecke, Christian; Cornberg, Markus; Welte, Karl; Blazar, Bruce R; Sauer, Martin G

    2009-04-30

    Antigen-presenting cells (APCs) of host origin drive graft-versus-leukemia (GVL) effects but can also trigger life-threatening graft-versus-host disease (GVHD) after hematopoietic cell transplantation (HCT) across major histocompatibility complex (MHC) barriers. We show that in vitro priming of donor lymphocytes can circumvent the need of recipient-derived APCs in vivo for mediating robust GVL effects and significantly diminishes the risk of severe GVHD. In vitro, generated and expanded T cells (ETCs) mediate anti-leukemia effects only when primed on recipient-derived APCs. Loading of APCs in vitro with leukemia cell lysate, chimerism status of the recipient, and timing of adoptive transfer after HCT are important factors determining the outcome. Delayed transfer of ETCs resulted in strong GVL effects in leukemia-bearing full chimera (FC) and mixed chimera (MC) recipients, which were comparable with the GVL/GVHD rates observed after the transfer of naive donor lymphocyte infusion (DLI). Upon early transfer, GVL effects were more pronounced with ETCs but at the expense of significant GVHD. The degree of GVHD was most severe in MCs after transfer of ETCs that had been in vitro primed either on nonpulsed recipient-derived APCs or with donor-derived APCs.

  1. Overcoming the bottleneck of platelet lysate supply in large-scale clinical expansion of adipose-derived stem cells

    DEFF Research Database (Denmark)

    Glovinski, Peter Viktor; Herly, Mikkel; Mathiasen, Anders B

    2017-01-01

    BACKGROUND: Platelet lysates (PL) represent a promising replacement for xenogenic growth supplement for adipose-derived stem cell (ASC) expansions. However, fresh platelets from human blood donors are not clinically feasible for large-scale cell expansion based on their limited supply. Therefore......, we tested PLs prepared via three methods from outdated buffy coat-derived platelet concentrates (PCs) to establish an efficient and feasible expansion of ASCs for clinical use. METHODS: PLs were prepared by the freeze-thaw method from freshly drawn platelets or from outdated buffy coat-derived PCs...... time, cell yield, differentiation potential and cell surface markers. Gene expression profiles were analyzed using microarray assays, and growth factor concentrations in the cell culture medium were measured using enzyme-linked immunosorbent assay (ELISA). RESULTS: Of the three PL compositions produced...

  2. Vaccination with melanoma lysate-pulsed dendritic cells, of patients with advanced colorectal carcinoma: report from a phase I study

    DEFF Research Database (Denmark)

    Burgdorf, S K; Fischer, A; Claesson, M H

    2006-01-01

    and selected melanoma cell line enriched in expression of MAGE-A antigens and deficient in expression of melanoma differentiation antigens: tyrosinase, MART-1 and gp100. Vaccinations were administered intradermally on the proximal thigh with a total of five given vaccines at 2 weeks intervals. Each vaccine...

  3. High DNA stability in white blood cells and buffy coat lysates stored at ambient temperature under anoxic and anhydrous atmosphere.

    Directory of Open Access Journals (Sweden)

    Anne-Lise Fabre

    Full Text Available Conventional storage of blood-derived fractions relies on cold. However, lately, ambient temperature preservation has been evaluated by several independent institutions that see economic and logistic advantages in getting rid of the cold chain. Here we validated a novel procedure for ambient temperature preservation of DNA in white blood cell and buffy coat lysates based on the confinement of the desiccated biospecimens under anoxic and anhydrous atmosphere in original hermetic minicapsules. For this validation we stored encapsulated samples either at ambient temperature or at several elevated temperatures to accelerate aging. We found that DNA extracted from stored samples was of good quality with a yield of extraction as expected. Degradation rates were estimated from the average fragment size of denatured DNA run on agarose gels and from qPCR reactions. At ambient temperature, these rates were too low to be measured but the degradation rate dependence on temperature followed Arrhenius' law, making it possible to extrapolate degradation rates at 25°C. According to these values, the DNA stored in the encapsulated blood products would remain larger than 20 kb after one century at ambient temperature. At last, qPCR experiments demonstrated the compatibility of extracted DNA with routine DNA downstream analyses. Altogether, these results showed that this novel storage method provides an adequate environment for ambient temperature long term storage of high molecular weight DNA in dehydrated lysates of white blood cells and buffy coats.

  4. High DNA stability in white blood cells and buffy coat lysates stored at ambient temperature under anoxic and anhydrous atmosphere

    Science.gov (United States)

    Luis, Aurélie; Colotte, Marthe; Tuffet, Sophie; Bonnet, Jacques

    2017-01-01

    Conventional storage of blood-derived fractions relies on cold. However, lately, ambient temperature preservation has been evaluated by several independent institutions that see economic and logistic advantages in getting rid of the cold chain. Here we validated a novel procedure for ambient temperature preservation of DNA in white blood cell and buffy coat lysates based on the confinement of the desiccated biospecimens under anoxic and anhydrous atmosphere in original hermetic minicapsules. For this validation we stored encapsulated samples either at ambient temperature or at several elevated temperatures to accelerate aging. We found that DNA extracted from stored samples was of good quality with a yield of extraction as expected. Degradation rates were estimated from the average fragment size of denatured DNA run on agarose gels and from qPCR reactions. At ambient temperature, these rates were too low to be measured but the degradation rate dependence on temperature followed Arrhenius’ law, making it possible to extrapolate degradation rates at 25°C. According to these values, the DNA stored in the encapsulated blood products would remain larger than 20 kb after one century at ambient temperature. At last, qPCR experiments demonstrated the compatibility of extracted DNA with routine DNA downstream analyses. Altogether, these results showed that this novel storage method provides an adequate environment for ambient temperature long term storage of high molecular weight DNA in dehydrated lysates of white blood cells and buffy coats. PMID:29190767

  5. Evaluation of human platelet lysate and dimethyl sulfoxide as cryoprotectants for the cryopreservation of human adipose-derived stem cells.

    Science.gov (United States)

    Wang, Chuan; Xiao, Ran; Cao, Yi-Lin; Yin, Hong-Yu

    2017-09-09

    Cryopreservation provides an effective technique to maintain the functional properties of human adipose-derived stem cells (ASCs). Dimethylsulfoxide (DMSO) and fetal bovine serum (FBS) are frequently used as cryoprotectants for this purpose. However, the use of DMSO can result in adverse effects and toxic reactions and FBS can introduce risks of viral, prion, zoonose contaminations and evoke immune responses after injection. It is therefore crucial to reduce DMSO concentrations and use serum-free solution in the cryopreservation process. Human platelet lysate (PL) is a promising candidate for use as an alternative to DMSO and FBS. Therefore, in this study, with an aim to identify a cryoprotective agent for ASC cryopreservation, we determined the viability, proliferation potential, phenotype, and differentiation potential of fresh ASCs and ASCs cryopreserved using different combinations of three cryoprotective agents: fetal bovine serum (FBS), dimethylsulfoxide (DMSO), and human platelet lysate (PL). The viability of the ASCs cryopreserved with 90% FBS and 10% DMSO, 95% FBS and 5% DMSO, and 97% PL and 3% DMSO was >80%, and the proliferation potentials, cell phenotypes, and differentiation potentials of these groups were similar to those of fresh ASCs. Together, our findings suggest that a combination of 97% PL and 3% DMSO is an ideal cryoprotective agent for the efficient cryopreservation of human ASCs. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Precision cancer immunotherapy: optimizing dendritic cell-based strategies to induce tumor antigen-specific T-cell responses against individual patient tumors.

    Science.gov (United States)

    Osada, Takuya; Nagaoka, Koji; Takahara, Masashi; Yang, Xiao Yi; Liu, Cong-Xiao; Guo, Hongtao; Roy Choudhury, Kingshuk; Hobeika, Amy; Hartman, Zachary; Morse, Michael A; Lyerly, H Kim

    2015-05-01

    Most dendritic cell (DC)-based vaccines have loaded the DC with defined antigens, but loading with autologos tumor-derived antigens would generate DCs that activate personalized tumor-specific T-cell responses. We hypothesized that DC matured with an optimized combination of reagents and loaded with tumor-derived antigens using a clinically feasible electroporation strategy would induce potent antitumor immunity. We first studied the effects on DC maturation and antigen presentation of the addition of picibanil (OK432) to a combination of zoledronic acid, tumor necrosis factor-α, and prostaglandin E2. Using DC matured with the optimized combination, we tested 2 clinically feasible sources of autologous antigen for electroloading, total tumor mRNA or total tumor lysate, to determine which stimulated more potent antigen-specific T cells in vitro and activated more potent antitumor immunity in vivo. The combination of tumor necrosis factor-α/prostaglandin E2/zoledronic acid/OK432 generated DC with high expression of maturation markers and antigen-specific T-cell stimulatory function in vitro. Mature DC electroloaded with tumor-derived mRNA [mRNA electroporated dendritic cell (EPDC)] induced greater expansion of antigen-specific T cells in vitro than DC electroloaded with tumor lysate (lysate EPDC). In a therapeutic model of MC38-carcinoembryonic antigen colon cancer-bearing mice, vaccination with mRNA EPDC induced the most efficient anti-carcinoembryonic antigen cellular immune response, which significantly suppressed tumor growth. In conclusion, mature DC electroloaded with tumor-derived mRNA are a potent cancer vaccine, especially useful when specific tumor antigens for vaccination have not been identified, allowing autologous tumor, and if unavailable, allogeneic cell lines to be used as an unbiased source of antigen. Our data support clinical testing of this strategy.

  7. Data from SILAC-based quantitative analysis of lysates from mouse microglial cells treated with Withaferin A (WA

    Directory of Open Access Journals (Sweden)

    Malathi Narayan

    2016-06-01

    Full Text Available Mass spectrometry data collected in a study analyzing the effect of withaferin A (WA on a mouse microglial (N9 cell line is presented in this article. Data was collected from SILAC-based quantitative analysis of lysates from mouse microglial cells treated with either WA or DMSO vehicle control. This article reports all the proteins that were identified in this analysis. The data presented here is related to the published research article on the effect of WA on the differential regulation of proteins in mouse microglial cells [1]. Mass spectrometry data has also been deposited in the ProteomeXchange with the identifier http://www.ebi.ac.uk/pride/archive/projects/PXD003032.

  8. Cultivation and irradiation of human fibroblasts in a medium enriched with platelet lysate for obtaining feeder layer in epidermal cell culture

    International Nuclear Information System (INIS)

    Yoshito, Daniele

    2011-01-01

    For over 30 years, the use of culture medium, enriched with bovine serum, and murines fibroblasts, with the rate of proliferation controlled by irradiation or by share anticarcinogenic drugs, has been playing successfully its role in assisting in the development of keratinocytes in culture, for clinical purposes. However, currently there is a growing concern about the possibility of transmitting prions and animals viruses to transplanted patients. Taking into account this concern, the present work aims to cultivate human fibroblasts in a medium enriched with human platelets lysate and determine the irradiation dose of these cells, for obtaining feeder layer in epidermal cell culture. For carrying out the proposed objective, platelets lysis has standardized, this lysate was used for human fibroblasts cultivation and the irradiation dose enough to inhibit its duplication was evaluated. Human keratinocytes were cultivated in these feeder layers, in culture medium enriched with the lysate. With these results we conclude that the 10% platelets lysate promoted a better adhesion and proliferation of human fibroblasts and in all dose levels tested (60 to 300 Gy), these had their mitotic activity inactivated by ionizing irradiation, being that the feeder layers obtained with doses from 70 to 150 Gy were those that provided the best development of keratinocytes in medium containing 2.5% of human platelet lysate. Therefore, it was possible to standardize both the cultivation of human fibroblasts as its inactivation for use as feeder layer in culture of keratinocytes, so as to eliminate xenobiotics components. (author)

  9. Highly Efficient In Vitro Reparative Behaviour of Dental Pulp Stem Cells Cultured with Standardised Platelet Lysate Supplementation

    Directory of Open Access Journals (Sweden)

    Pasquale Marrazzo

    2016-01-01

    Full Text Available Dental pulp is an accessible source of multipotent mesenchymal stromal cells (MSCs. The perspective role of dental pulp stem cells (DPSCs in regenerative medicine demands an in vitro expansion and in vivo delivery which must deal with the safety issues about animal serum, usually required in cell culture practice. Human platelet lysate (PL contains autologous growth factors and has been considered as valuable alternative to fetal bovine serum (FBS in cell cultures. The optimum concentration to be added of such supplement is highly dependent on its preparation whose variability limits comparability of results. By in vitro experiments, we aimed to evaluate a standardised formulation of pooled PL. A low selected concentration of PL (1% was able to support the growth and maintain the viability of the DPSCs. The use of PL in cell cultures did not impair cell surface signature typically expressed by MSCs and even upregulated the transcription of Sox2. Interestingly, DPSCs cultured in presence of PL exhibited a higher healing rate after injury and are less susceptible to toxicity mediated by exogenous H2O2 than those cultured with FBS. Moreover, PL addition was shown as a suitable option for protocols promoting osteogenic and chondrogenic differentiation of DPSCs. Taken together, our results indicated that PL is a valid substitute of FBS to culture and differentiate DPSCs for clinical-grade use.

  10. Comparison of LTQ-Orbitrap Velos and Q-Exactive for proteomic analysis of 1-1000 ng RAW 264.7 cell lysate digests

    Science.gov (United States)

    Sun, Liangliang; Zhu, Guijie

    2013-01-01

    Rational There is interest in extending bottom-up proteomics to the smallest possible sample size. We investigated the performance of two modern instruments for the analysis of samples ranging from 1 ng to 1 µg of RAW 264.7 cell lysate digests. Methods A UPLC system coupled with either an LTQ-Orbitrap Velos or a Q-Exactive mass spectrometers was used for peptide separation and identification. Results For 1–1,000 ng RAW 264.7 cell lysate digests, the Q-Exactive generated 10–83% more protein groups and 11–109% more peptides than the LTQ-Orbitrap Velos (higher-energy collisional dissociation, HCD) with MASCOT database searching, due to faster scan rate and higher resolution. In addition, HCD and collision induced dissociation (CID) modes of the LTQ-Orbitrap Velos were compared. HCD produced higher peptide and protein group IDs than CID for 1–1,000 ng RAW 264.7 cell lysate digests with MASCOT database searching. Database searching results from SEQUEST and MASCOT were also compared and comparable protein group IDs were obtained from the two search engines. Conclusions These results indicated that Q-Exactive outperformed LTQ-Orbitrap Velos for shotgun proteomics analysis of 1 to 1,000 ng RAW 264.7 cell lysate digests in terms of obtained peptide and protein group IDs. PMID:23239329

  11. A sensitive fluorescence-based assay for monitoring GM2 ganglioside hydrolysis in live patient cells and their lysates.

    Science.gov (United States)

    Tropak, Michael B; Bukovac, Scott W; Rigat, Brigitte A; Yonekawa, Sayuri; Wakarchuk, Warren; Mahuran, Don J

    2010-03-01

    Enzyme enhancement therapy, utilizing small molecules as pharmacological chaperones, is an attractive approach for the treatment of lysosomal storage diseases that are associated with protein misfolding. However, pharmacological chaperones are also inhibitors of their target enzyme. Thus, a major concern with this approach is that, despite enhancing protein folding within, and intracellular transport of the functional mutant enzyme out of the endoplasmic reticulum, the chaperone will continue to inhibit the enzyme in the lysosome, preventing substrate clearance. Here we demonstrate that the in vitro hydrolysis of a fluorescent derivative of lyso-GM2 ganglioside, like natural GM2 ganglioside, is specifically carried out by the beta-hexosaminidase A isozyme, requires the GM2 activator protein as a co-factor, increases when the derivative is incorporated into anionic liposomes and follows similar Michaelis-Menten kinetics. This substrate can also be used to differentiate between lysates from normal and GM2 activator-deficient cells. When added to the growth medium of cells, the substrate is internalized and primarily incorporated into lysosomes. Utilizing adult Tay-Sachs fibroblasts that have been pre-treated with the pharmacological chaperone Pyrimethamine and subsequently loaded with this substrate, we demonstrate an increase in both the levels of mutant beta-hexosaminidase A and substrate-hydrolysis as compared to mock-treated cells.

  12. Capillary zone electrophoresis-multiple reaction monitoring from 100 pg of RAW 264.7 cell lysate digest.

    Science.gov (United States)

    Sun, Liangliang; Li, Yihan; Champion, Matthew M; Zhu, Guijie; Wojcik, Roza; Dovichi, Norman J

    2013-06-07

    Capillary zone electrophoresis-multiple/single reaction monitoring (CZE-MRM/SRM), which employed an electrokinetically driven sheath-flow electrospray interface, was used for the rapid and highly sensitive detection of protein analytes in complex tryptic digests. MRM channels were developed against a commercial exponential mixture of bovine proteins. Five proteins spanning four orders of magnitude concentration range were confidently detected from only 2.5 ng of the digest mixture; the mass detection limits (S/N = 3) of two detected proteins, alpha-casein and glutamate dehydrogenase were about 600 zmol and 30 amol, respectively. This technique was then applied to a RAW 264.7 cell lysate digest. Three proteins were confidently and reproducibly detected from 100 pg of this digest. The sample amount corresponds to the approximate protein content from a single cell, which suggests that CZE-MRM may be a useful analytical tool in chemical cytometry. In addition to providing highly sensitive detection of proteins in complex mixtures, this system is highly rapid; migration time of the protein digests was less than 10 min.

  13. Disposable Amperometric Immunosensor for the Determination of Human P53 Protein in Cell Lysates Using Magnetic Micro-Carriers

    Directory of Open Access Journals (Sweden)

    María Pedrero

    2016-11-01

    Full Text Available An amperometric magnetoimmunosensor for the determination of human p53 protein is described in this work using a sandwich configuration involving the covalent immobilization of a specific capture antibody onto activated carboxylic-modified magnetic beads (HOOC-MBs and incubation of the modified MBs with a mixture of the target protein and horseradish peroxidase-labeled antibody (HRP-anti-p53. The resulting modified MBs are captured by a magnet placed under the surface of a disposable carbon screen-printed electrode (SPCE and the amperometric responses are measured at −0.20 V (vs. an Ag pseudo-reference electrode, upon addition of hydroquinone (HQ as a redox mediator and H2O2 as the enzyme substrate. The magnetoimmunosensing platform was successfully applied for the detection of p53 protein in different cell lysates without any matrix effect after a simple sample dilution. The results correlated accurately with those provided by a commercial ELISA kit, thus confirming the immunosensor as an attractive alternative for rapid and simple determination of this protein using portable and affordable instrumentation.

  14. A new application of aptamer: One-step purification and immobilization of enzyme from cell lysates for biocatalysis.

    Science.gov (United States)

    Qiao, Lifeng; Lv, Bo; Feng, Xudong; Li, Chun

    2015-06-10

    Aptamers are nucleic acid-based high affinity ligands that are able to capture their corresponding target through molecular recognition. In this study, several DNA aptamers with high affinity and specificity for β-glucuronidases (PGUS-E) were obtained by our modified SELEX method. Among them, Apt5 and Apt9 were selected as representatives and covalently linked to magnetic beads, respectively. The aptamer-modified magnetic beads were characterized and successfully applied to one-step purification and immobilization of PGUS-E from the complex cell lysates. By conveniently adjusting the pH and ion strength, the PGUS-E purities reached 84% for Apt5-modified beads and 88% for Apt9-modified beads. Moreover, the maximum PGUS-E capturing capacity of the Apt5 and Apt9 modified magnetic beads were found to be 31.75μg/mg and 32.95μg/mg, respectively. The immobilized PGUS-E on aptamer-based magnetic beads showed good reusability, and the conversion of glycyrrhizin still remained more than 70% after 7 cycles. In addition, the aptamer-modified beads support can be easily regenerated, and the conversion rate of glycyrrhizin (GL) was still 62% after the 7th cycle of regeneration. This investigation can be easily extended to other enzyme systems and may help open a generic route to develop a novel enzyme immobilization technology for biocatalysis based on aptamer. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. A novel whole-cell lysate kinase assay identifies substrates of the p38 MAPK in differentiating myoblasts

    Directory of Open Access Journals (Sweden)

    Knight James DR

    2012-03-01

    Full Text Available Abstract Background The p38α mitogen-activated protein kinase (MAPK is a critical mediator of myoblast differentiation, and does so in part through the phosphorylation and regulation of several transcription factors and chromatin remodelling proteins. However, whether p38α is involved in processes other than gene regulation during myogenesis is currently unknown, and why other p38 isoforms cannot compensate for its loss is unclear. Methods To further characterise the involvement of p38α during myoblast differentiation, we developed and applied a simple technique for identifying relevant in vivo kinase substrates and their phosphorylation sites. In addition to identifying substrates for one kinase, the technique can be used in vitro to compare multiple kinases in the same experiment, and we made use of this to study the substrate specificities of the p38α and β isoforms. Results Applying the technique to p38α resulted in the identification of seven in vivo phosphorylation sites on six proteins, four of which are cytoplasmic, in lysate derived from differentiating myoblasts. An in vitro comparison with p38β revealed that substrate specificity does not discriminate these two isoforms, but rather that their distinguishing characteristic appears to be cellular localisation. Conclusion Our results suggest p38α has a novel cytoplasmic role during myogenesis and that its unique cellular localisation may be why p38β and other isoforms cannot compensate for its absence. The substrate-finding approach presented here also provides a necessary tool for studying the hundreds of protein kinases that exist and for uncovering the deeper mechanisms of phosphorylation-dependent cell signalling.

  16. Rapid and sensitive detection of multiple microRNAs in cell lysate by low-fouling surface plasmon resonance biosensor

    Czech Academy of Sciences Publication Activity Database

    Vaisocherová, Hana; Šípová, Hana; Víšová, Ivana; Bocková, Markéta; Špringer, Tomáš; Ermini, Maria Laura; Chadtová Song, Xue; Krejčík, Z.; Chrastinová, L.; Pastva, O.; Pimková, K.; Merkerová-Dostálová, M.; Dyr, J. E.; Homola, Jiří

    2015-01-01

    Roč. 70, August 05 (2015), s. 226-231 ISSN 0956-5663 R&D Projects: GA ČR(CZ) GBP205/12/G118 Institutional support: RVO:67985882 Keywords : Erythrocyte lysate * Polymer brushes * DNA array Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 7.476, year: 2015

  17. Harnessing Dendritic Cells for Tumor Antigen Presentation

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-04-26

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

  18. An innovative immunosensor for ultrasensitive detection of breast cancer specific carbohydrate (CA 15-3) in unprocessed human plasma and MCF-7 breast cancer cell lysates using gold nanospear electrochemically assembled onto thiolated graphene quantum dots.

    Science.gov (United States)

    Hasanzadeh, Mohammad; Tagi, Solmaz; Solhi, Elham; Mokhtarzadeh, Ahad; Shadjou, Nasrin; Eftekhari, Aziz; Mahboob, Soltanali

    2018-04-03

    The accurate quantification of the level of breast cancer specific protein CA 15-3 in serum is crucial for cancer prognosis. This work, a novel and sensitive label-free immunoassay based on gold nanospear (Au NSs) electrochemically assembled onto thiolated graphene quantum dots (CysA/GQDs) for the detection of CA 15-3 antibodies. The CysA/Au NSs/GQDs hybrid interface provides a large surface area for the effective immobilization of CA 15-3 antigens, as well as it ascertains the bioactivity and stability of immobilized CA 15-3 antigens. Field emission scanning electron microscope (FE-SEM), and EDS photoelectron spectroscopies were used to monitor the sensor fabrication. Also, cyclic voltammetry was used to quantify the extent of Au NSs' surface coverage by CA 15-3 antigens. Square wave voltammetry (SWV) was employed to investigate the immunosensor fabrication and to monitor the binding events between CA 15-3 antigens-antibodies. Under optimized experimental conditions, the immunosensor displayed good sensitivity and specificity. The CA 15-3 were detected in a concentration as low as 0.11U/mL with a linear range from 0.16-125U/mL. The high sensitivity of the immunosensor may derive from the high loading of CA 15-3 antibodies on CysA/Au NSs/GQDs hybrid interface which increases the number of binding events. The method was successfully applied assay of the CA 15-3 in unprocessed human plasma samples. Also, proposed immunosensor was applied to the assay of CA 15-3 malignant cell line lysates (human breast adenocarcinoma cell line-MCF-7). Copyright © 2018. Published by Elsevier B.V.

  19. 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’

  20. The Antigen Presenting Cells Instruct Plasma Cell Differentiation

    Directory of Open Access Journals (Sweden)

    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.

  1. [Immune response of melanoma antigen gene-3 modified dendritic cell vaccines in gastric carcinoma].

    Science.gov (United States)

    He, Song-bing; Wang, Liang; Zhang, Yan-yun

    2009-05-01

    To investigate the anti-gastric carcinoma immunological efficacy of dendritic cells (DC) precursors, that were mobilized into the peripheral blood by injection of macrophage inflammation protein-1 alpha (MIP-1 alpha), and induced by DC vaccine expressing melanoma antigen gene-3 (MAGE-3) ex vivo and in vivo. 615 mice were injected with MIP-1 alpha via the tail vein. Freshly isolated B220(-) CD11c+ cells were cultured with cytokines and assayed by phenotype analysis and mixed lymphocyte reaction (MLR). For adenoviral (Ad)-mediated gene transduction, cultured B220(-) CD11c+ cells were incubated with Ad-melanoma antigen gene-3. MIP-1 alpha-mobilized B220(-) CD11c+ cells pulsed MFC cells tumor lysate were used as positive control. The stimulated DC vaccination-induced T lymphocytes, and the killing effect of the T cells on gastric carcinoma cells were assayed by MTT. INF-gamma production was determined with the INF-gamma ELISA kit. To establish the solid tumor model, groups of 615 mice were injected with MFC cells subcutaneously into the abdominal wall. MIP-1 alpha-mobilized DC vaccines expressing MAGE-3 gene were used to immunize the mice after the challenge of MFC cells, then the tumor size and the survival of mice were examined to detect the therapeutic effect of DC vaccines. B220(-) CD11c+ cells increased obviously after MIP-1 alpha injection, and freshly isolated B220(-) CD11c+ cells cultured with mGM-CSF, IL-4, and mTNF-alpha were phenotypically identical to typical DC, gained the capacity to stimulate allogeneic T cells. These MIP-1 alpha-mobilized DCs were transduced with Ad-MAGE-3, which were prepared for DC vaccines expressing tumor antigen. T lymphocytes stimulated with DC-transduced with Ad-MAGE-3 showed specific killing effect on gastric carcinoma cells and produced high levels of INF-gamma [(1460.00 +/- 16.82) pg/ml]. Five days after the MFC cells challenge, the mice were subsequently injected with DC vaccines. The tumor size of the experimental group was

  2. The antigen presenting cells instruct plasma cell differentiation.

    Science.gov (United States)

    Xu, Wei; Banchereau, Jacques

    2014-01-06

    The professional antigen presenting cells (APCs), including many subsets of dendritic cells and macrophages, not only mediate prompt but non-specific 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 (PCs), 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 PCs 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. The natural killer cell response and tumor debulking are associated with prolonged survival in recurrent glioblastoma patients receiving dendritic cells loaded with autologous tumor lysates

    Science.gov (United States)

    Pellegatta, Serena; Eoli, Marica; Frigerio, Simona; Antozzi, Carlo; Bruzzone, Maria Grazia; Cantini, Gabriele; Nava, Sara; Anghileri, Elena; Cuppini, Lucia; Cuccarini, Valeria; Ciusani, Emilio; Dossena, Marta; Pollo, Bianca; Mantegazza, Renato; Parati, Eugenio A.; Finocchiaro, Gaetano

    2013-01-01

    Recurrent glioblastomas (GBs) are highly aggressive tumors associated with a 6–8 mo survival rate. In this study, we evaluated the possible benefits of an immunotherapeutic strategy based on mature dendritic cells (DCs) loaded with autologous tumor-cell lysates in 15 patients affected by recurrent GB. The median progression-free survival (PFS) of this patient cohort was 4.4 mo, and the median overall survival (OS) was 8.0 mo. Patients with small tumors at the time of the first vaccination (< 20 cm3; n = 8) had significantly longer PFS and OS than the other patients (6.0 vs. 3.0 mo, p = 0.01; and 16.5 vs. 7.0 mo, p = 0.003, respectively). CD8+ T cells, CD56+ natural killer (NK) cells and other immune parameters, such as the levels of transforming growth factor β, vascular endothelial growth factor, interleukin-12 and interferon γ (IFNγ), were measured in the peripheral blood and serum of patients before and after immunization, which enabled us to obtain a vaccination/baseline ratio (V/B ratio). An increased V/B ratio for NK cells, but not CD8+ T cells, was significantly associated with prolonged PFS and OS. Patients exhibiting NK-cell responses were characterized by high levels of circulating IFNγ and E4BP4, an NK-cell transcription factor. Furthermore, the NK cell V/B ratio was inversely correlated with the TGFβ2 and VEGF V/B ratios. These results suggest that tumor-loaded DCs may increase the survival rate of patients with recurrent GB after effective tumor debulking, and emphasize the role of the NK-cell response in this therapeutic setting. PMID:23802079

  4. A practical approach to pancreatic cancer immunotherapy using resected tumor lysate vaccines processed to express α-gal epitopes.

    Directory of Open Access Journals (Sweden)

    Kenta Furukawa

    Full Text Available Single-agent immunotherapy is ineffective against poorly immunogenic cancers, including pancreatic ductal adenocarcinoma (PDAC. The aims of this study were to demonstrate the feasibility of production of novel autologous tumor lysate vaccines from resected PDAC tumors, and verify vaccine safety and efficacy.Fresh surgically resected tumors obtained from human patients were processed to enzymatically synthesize α-gal epitopes on the carbohydrate chains of membrane glycoproteins. Processed membranes were analyzed for the expression of α-gal epitopes and the binding of anti-Gal, and vaccine efficacy was assessed in vitro and in vivo.Effective synthesis of α-gal epitopes was demonstrated after processing of PDAC tumor lysates from 10 different patients, and tumor lysates readily bound an anti-Gal monoclonal antibody. α-gal(+ PDAC tumor lysate vaccines elicited strong antibody production against multiple tumor-associated antigens and activated multiple tumor-specific T cells. The lysate vaccines stimulated a robust immune response in animal models, resulting in tumor suppression and a significant improvement in survival without any adverse events.Our data suggest that α-gal(+ PDAC tumor lysate vaccination may be a practical and effective new immunotherapeutic approach for treating pancreatic cancer.

  5. Is buffer a good proxy for a crowded cell-like environment? A comparative NMR study of calmodulin side-chain dynamics in buffer and E. coli lysate.

    Directory of Open Access Journals (Sweden)

    Michael P Latham

    Full Text Available Biophysical studies of protein structure and dynamics are typically performed in a highly controlled manner involving only the protein(s of interest. Comparatively fewer such studies have been carried out in the context of a cellular environment that typically involves many biomolecules, ions and metabolites. Recently, solution NMR spectroscopy, focusing primarily on backbone amide groups as reporters, has emerged as a powerful technique for investigating protein structure and dynamics in vivo and in crowded "cell-like" environments. Here we extend these studies through a comparative analysis of Ile, Leu, Val and Met methyl side-chain motions in apo, Ca(2+-bound and Ca(2+, peptide-bound calmodulin dissolved in aqueous buffer or in E. coli lysate. Deuterium spin relaxation experiments, sensitive to pico- to nano-second time-scale processes and Carr-Purcell-Meiboom-Gill relaxation dispersion experiments, reporting on millisecond dynamics, have been recorded. Both similarities and differences in motional properties are noted for calmodulin dissolved in buffer or in lysate. These results emphasize that while significant insights can be obtained through detailed "test-tube" studies, experiments performed under conditions that are "cell-like" are critical for obtaining a comprehensive understanding of protein motion in vivo and therefore for elucidating the relation between motion and function.

  6. Integrated culture platform based on a human platelet lysate supplement for the isolation and scalable manufacturing of umbilical cord matrix-derived mesenchymal stem/stromal cells.

    Science.gov (United States)

    de Soure, António M; Fernandes-Platzgummer, Ana; Moreira, Francisco; Lilaia, Carla; Liu, Shi-Hwei; Ku, Chen-Peng; Huang, Yi-Feng; Milligan, William; Cabral, Joaquim M S; da Silva, Cláudia L

    2017-05-01

    Umbilical cord matrix (UCM)-derived mesenchymal stem/stromal cells (MSCs) are promising therapeutic candidates for regenerative medicine settings. UCM MSCs have advantages over adult cells as these can be obtained through a non-invasive harvesting procedure and display a higher proliferative capacity. However, the high cell doses required in the clinical setting make large-scale manufacturing of UCM MSCs mandatory. A commercially available human platelet lysate-based culture supplement (UltraGRO TM , AventaCell BioMedical) (5%(v/v)) was tested to effectively isolate UCM MSCs and to expand these cells under (1) static conditions, using planar culture systems and (2) stirred culture using plastic microcarriers in a spinner flask. The MSC-like cells were isolated from UCM explant cultures after 11 ± 2 days. After five passages in static culture, UCM MSCs retained their immunophenotype and multilineage differentiation potential. The UCM MSCs cultured under static conditions using UltraGRO TM -supplemented medium expanded more rapidly compared with UCM MSCs expanded using a previously established protocol. Importantly, UCM MSCs were successfully expanded under dynamic conditions on plastic microcarriers using UltraGRO TM -supplemented medium in spinner flasks. Upon an initial 54% cell adhesion to the beads, UCM MSCs expanded by >13-fold after 5-6 days, maintaining their immunophenotype and multilineage differentiation ability. The present paper reports the establishment of an easily scalable integrated culture platform based on a human platelet lysate supplement for the effective isolation and expansion of UCM MSCs in a xenogeneic-free microcarrier-based system. This platform represents an important advance in obtaining safer and clinically meaningful MSC numbers for clinical translation. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Induction of an antitumor response using dendritic cells transfected with DNA constructs encoding the HLA-A*02:01-restricted epitopes of tumor-associated antigens in culture of mononuclear cells of breast cancer patients.

    Science.gov (United States)

    Sennikov, Sergey Vital'evich; Shevchenko, Julia Alexandrovna; Kurilin, Vasilii Vasil'evich; Khantakova, Julia Nikolaevna; Lopatnikova, Julia Anatol'evna; Gavrilova, Elena Vasil'evna; Maksyutov, Rinat Amirovich; Bakulina, Anastasiya Yur'evna; Sidorov, Sergey Vasil'evich; Khristin, Alexander Alexandrovich; Maksyutov, Amir Zakievich

    2016-02-01

    Advances in oncoimmunology related to the definition of the basic mechanisms of the formation of antitumor immune response, as well as the opening of tumor-associated antigens recognized by immune cells, allowed to start developing ways to influence the effector cells of the immune system to generate effective antitumor cytotoxic response. We investigated the possibility to stimulate an antitumor response in a culture of mononuclear cells of breast cancer patients by dendritic cells transfected with HLA-A*02:01-restricted DNA constructs. We isolated dendritic cells from peripheral blood monocytes and delivered our constructs to these cells by magnetic transfection. Additionally, a series of experiments with loading of dendritic cells with autologous tumor cell lysate antigens was conducted. We have shown that dendritic cells transfected with the HLA-A*02:01-restricted DNA constructs are effective in inducing an antitumor response in a culture of mononuclear cells of breast cancer patients. Dendritic cells transfected with DNA constructor dendritic cells loaded with lysate antigens revealed a comparable stimulated cytotoxic response of mononuclear cells to these two ways of antigen delivery. We conclude that using DNA constructs in conjunction with patient stratification by HLA type allows the application of transfected DCs as an effective method to stimulate antitumor immunity in vitro.

  8. T cell recognition of breast cancer antigens

    DEFF Research Database (Denmark)

    Petersen, Nadia Viborg; Andersen, Sofie Ramskov; Andersen, Rikke Sick

    Recent studies are encouraging research of breast cancer immunogenicity to evaluate the applicability ofimmunotherapy as a treatment strategy. The epitope landscape in breast cancer is minimally described, thus it is necessary to identify T cell targets to develop immune mediated therapies.......This project investigates four proteins commonly upregulated in breast cancer and thus probable tumor associated antigens (TAAs). Aromatase, prolactin, NEK3, and PIAS3 contribute to increase growth, survival, and motility of malignant cells. Aspiring to uncover novel epitopes for cytotoxic T cells, a reverse...... recognition utilizing DNA barcode labeled MHC multimers to screen peripheral blood lymphocytes from breast cancer patients and healthy donor samples. Signif-icantly more TAA specific T cell responses were detected in breast cancer patients than healthy donors for both HLA-A*0201 (P

  9. Real-time PCR analysis of genes encoding tumor antigens in esophageal tumors and a cancer vaccine

    DEFF Research Database (Denmark)

    Weinert, Brian T; Krishnadath, Kausilia K; Milano, Francesca

    2009-01-01

    Tumor antigens are the primary target of therapeutic cancer vaccines. We set out to define and compare the expression pattern of tumor antigen genes in esophagus carcinoma biopsies and in an allogeneic tumor lysate-based cancer vaccine, MelCancerVac. Cells used for vaccine production were treated...... with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-aza-CdR) to determine whether this treatment could improve the profile of tumor antigen genes expressed in these cells. In addition, the presence of MAGE-A tumor antigen protein was evaluated in the purified tumor cell lysate used...

  10. LOCALIZATION OF ANTIGEN IN TISSUE CELLS

    Science.gov (United States)

    Coons, Albert H.; Leduc, Elizabeth H.; Kaplan, Melvin H.

    1951-01-01

    The fate of three proteins, crystalline hen's egg albumin, crystalline bovine plasma albumin, and human plasma γ-globulin, was traced after intravenous injection into mice. This was done by preparing frozen sections of quick-frozen tissue, allowing what foreign protein might be present in the section to react with homologous antibody labelled with fluorescein, and examining the section under the fluorescence microscope. By this means, which employs the serological specificity of the protein as a natural "marker," all three of these proteins were found in the cells of the reticulo-endothelial system, the connective tissue, the vascular endothelium, the lymphocytes of spleen and lymph node, and the epithelium of the kidney tubules, the liver, and in very small amounts in the adrenal. The central nervous system was not studied. All three persisted longest in the reticulo-endothelial system and the connective tissue, and in the doses employed egg white (10 mg.) was no longer detectable after 1 day, bovine albumin (10 mg.) after 2 days, and human γ-globulin (4 mg.) after 6 days, although in a somewhat higher dose (10 mg.) human γ-globulin persisted longer than 8 days. Egg albumin differed from the others in not being detectable in the cells of the renal glomerulus. It was found that each of the three proteins was present in the nuclei of each cell type enumerated above, often in higher concentration than in the cytoplasm. Further, some of the nuclei not only contained antigen, soon after injection, but were also surrounded by a bright ring associated with the nuclear membrane. By means of photographic records under the fluorescence microscope of sections stained for antigen, and direct observation under the light microscope of the same field subsequently stained with hematoxylin and eosin, it could be determined that the antigen was not adsorbed to chromatin or nucleoli, but was apparently in solution in the nuclear sap. PMID:14803641

  11. Comparison of the LTQ-Orbitrap Velos and the Q-Exactive for proteomic analysis of 1-1000 ng RAW 264.7 cell lysate digests.

    Science.gov (United States)

    Sun, Liangliang; Zhu, Guijie; Dovichi, Norman J

    2013-01-15

    There is interest in extending bottom-up proteomics to the smallest possible sample size. We investigated the performance of two modern mass spectrometers for the analysis of samples ranging from 1 ng to 1 µg of RAW 264.7 cell lysate digests. An ultra-performance liquid chromatography (UPLC) system coupled with either an LTQ-Orbitrap Velos or a Q-Exactive mass spectrometer was used for peptide separation and identification. For 1-1000 ng RAW 264.7 cell lysate digests, the Q-Exactive generated 10-83% more protein groups and 11-109% more peptides than the LTQ-Orbitrap Velos (higher-energy collisional dissociation, HCD) with MASCOT database searching, due to its faster scan rate and higher resolution. In addition, HCD and collision-induced dissociation (CID) modes of the LTQ-Orbitrap Velos were compared. HCD produced higher peptide and protein group IDs than CID for 1-1000 ng RAW 264.7 cell lysate digests with MASCOT database searching. Database searching results from SEQUEST and MASCOT were also compared and comparable protein group IDs were obtained from the two search engines. The Q-Exactive outperformed the LTQ-Orbitrap Velos for shotgun proteomics analysis of 1 to 1000 ng RAW 264.7 cell lysate digests in terms of obtained peptide and protein group IDs. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Platelet lysate as a novel serum-free media supplement for the culture of equine bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Naskou, Maria C; Sumner, Scarlett M; Chocallo, Anna; Kemelmakher, Hannah; Thoresen, Merrilee; Copland, Ian; Galipeau, Jacques; Peroni, John F

    2018-03-22

    Mesenchymal stem cells (MSCs) produced for clinical purposes rely on culture media containing fetal bovine serum (FBS) which is xenogeneic and has the potential to significantly alter the MSC phenotype, rendering these cells immunogenic. As a result of bovine-derived exogenous proteins expressed on the cell surface, MSCs may be recognized by the host immune system as non-self and be rejected. Platelet lysate (PL) may obviate some of these concerns and shows promising results in human medicine as a possible alternative to FBS. Our goal was to evaluate the use of equine platelet lysate (ePL) pooled from donor horses in place of FBS to culture equine MSCs. We hypothesized that ePL, produced following apheresis, will function as the sole media supplement to accelerate the expansion of equine bone marrow-derived MSCs without altering their phenotype and their immunomodulatory capacity. Platelet concentrate was obtained via plateletpheresis and ePL were produced via freeze-thaw and centrifugation cycles. Population doublings (PD) and doubling time (DT) of bone marrow-derived MSCs (n = 3) cultured with FBS or ePL media were calculated. Cell viability, immunophenotypic analysis, and trilineage differentiation capacity of MSCs were assessed accordingly. To assess the ability of MSCs to modulate inflammatory responses, E. coli lipopolysaccharide (LPS)-stimulated monocytes were cocultured with MSCs cultured in the two different media formulations, and cell culture supernatants were assayed for the production of tumor necrosis factor (TNF)-α. Our results showed that MSCs cultured in ePL media exhibited similar proliferation rates (PD and DT) compared with those cultured in FBS at individual time points. MSCs cultured in ePL showed a statistically significant increased viability following a single washing step, expressed similar levels of MSC markers compared to FBS, and were able to differentiate towards the three lineages. Finally, MSCs cultured in ePL efficiently suppressed

  13. Assessment of in vivo anti-tumor activity of human umbilical vein endothelial cell vaccines prepared by various antigen forms.

    Science.gov (United States)

    Zhou, Ling; Si, Chunfeng; Li, Defang; Lu, Meiyu; Zhong, Weilan; Xie, Zeping; Guo, Lin; Zhang, Shumin; Xu, Maolei

    2018-03-01

    Human umbilical vein endothelial cell (HUVEC) vaccine has been proved as an effective whole-cell vaccine, but the modest therapeutic anti-tumor efficiency limits its clinical use. Various antigen forms, including paraformaldehyde-fixed HUVEC, glutaraldehyde-fixed HUVEC, HUVEC lysate and live HUVEC, have been intensively used in HUVEC vaccine preparation, however, the most effective antigen form has not yet been identified. In the present study, these four commonly used antigen forms were used to prepare vaccines named Para-Fixed-EC, Glu-Fixed-EC, Lysate-EC, and Live-EC respectively, and the anti-tumor efficacy of these four vaccines was investigated. Results showed that Live-EC exhibited the most favorable anti-tumor growth and metastasis effects among the four vaccines in both H22 hepatocellular carcinoma and Lewis lung cancer models. High titer anti-HUVEC antibodies were detected in Live-EC immunized mice sera, and the immune sera of Live-EC group could significantly inhibit HUVEC proliferation and tube formation. Moreover, T cells isolated from Live-EC immunized mice exhibited strong cytotoxicity against HUVEC cells, with an increasing IFN-γ and decreasing Treg production in Live-EC immunized mice. Finally, CD31 immunohistochemical analysis of the excised tumors verified a significant reduction in vessel density after Live-EC vaccination, which was in accordance with the anti-tumor efficiency. Taken together, all the results proved that live HUVEC was the most effective antigen form to induce robust HUVEC specific antibody and CTL responses, which could lead to the significant inhibition of tumor growth and metastasis. We hope the present findings would provide a rationale for the further optimization of HUVEC vaccine. Copyright © 2017. Published by Elsevier B.V.

  14. Endothelial cells present antigens in vivo

    Directory of Open Access Journals (Sweden)

    Tellides George

    2004-03-01

    Full Text Available Abstract Background Immune recognition of vascular endothelial cells (EC has been implicated in allograft rejection, protection against pathogens, and lymphocyte recruitment. However, EC pervade nearly all tissues and predominate in none, complicating any direct test of immune recognition. Here, we examined antigen presentation by EC in vivo by testing immune responses against E. coli β-galactosidase (β-gal in two lines of transgenic mice that express β-gal exclusively in their EC. TIE2-lacZ mice express β-gal in all EC and VWF-lacZ mice express β-gal in heart and brain microvascular EC. Results Transgenic and congenic wild type FVB mice immunized with β-gal expression vector DNA or β-gal protein generated high titer, high affinity antisera containing comparable levels of antigen-specific IgG1 and IgG2a isotypes, suggesting equivalent activation of T helper cell subsets. The immunized transgenic mice remained healthy, their EC continued to express β-gal, and their blood vessels showed no histological abnormalities. In response to β-gal in vitro, CD4+ and CD8+ T cells from immunized transgenic and FVB mice proliferated, expressed CD25, and secreted IFN-γ. Infection with recombinant vaccinia virus encoding β-gal raised equivalent responses in transgenic and FVB mice. Hearts transplanted from transgenic mice into FVB mice continued to beat and the graft EC continued to express β-gal. These results suggested immunological ignorance of the transgene encoded EC protein. However, skin transplanted from TIE2-lacZ onto FVB mice lost β-gal+ EC and the hosts developed β-gal-specific antisera, demonstrating activation of host immune effector mechanisms. In contrast, skin grafted from TIE2-lacZ onto VWF-lacZ mice retained β-gal+ EC and no antisera developed, suggesting a tolerant host immune system. Conclusion Resting, β-gal+ EC in transgenic mice tolerize specific lymphocytes that would otherwise respond against β-gal expressed by EC within

  15. Removal process of prion and parvovirus from human platelet lysates used as clinical-grade supplement for ex vivo cell expansion.

    Science.gov (United States)

    Kao, Yu-Chun; Bailey, Andy; Samminger, Bernhard; Tanimoto, Junji; Burnouf, Thierry

    2016-07-01

    Pooled human platelet lysate (HPL) is becoming the new gold standard as supplement for ex vivo cell culture for clinical protocols. However, the risk of pathogen contamination of HPL increases with the platelet pool size. We hypothesized that hollow fiber anion exchange membrane chromatography using QyuSpeed D (QSD) could remove resistant and untested bloodborne pathogens, such as parvoviruses and prions, from HPL-supplemented growth media without substantially affecting their capacity to support ex vivo cell expansion. Frozen or thawed platelet concentrates were serum-converted and centrifuged for obtaining HPL that was added to various growth media (ca. 100 mL), filtered through a 0.6-mL QSD membrane and characterized for proteins, growth factors and chemical composition. Capacity to expand Chinese hamster ovary, periodontal ligament, gingival fibroblast cells and Wharton's jelly mesenchymal stromal cells was studied. Removal of porcine parvovirus (PPV) and of the 263K prion strain of hamster-adapted scrapie was studied by spiking experiments following international guidelines. QSD had minimal impact on HPL-supplemented medium composition in proteins, growth factors and chemical content, nor capacity to expand and differentiate cells. In addition, QSD could remove ≥5.58 log10 [TCID50/mL] and ≥3.72 log10 of PPV and the 263K prion, respectively. QSD hollow fiber chromatography can be used to improve the virus and prion safety of HPL-supplemented media to safely expand cells for clinical protocols. These data bring new perspectives for increasingly safer use of pooled HPL in cell therapy and regenerative medicine applications. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  16. Donor T cells primed on leukemia lysate-pulsed recipient APCs mediate strong graft-versus-leukemia effects across MHC barriers in full chimeras

    OpenAIRE

    Ghosh, Arnab; Koestner, Wolfgang; Hapke, Martin; Schlaphoff, Verena; Länger, Florian; Baumann, Rolf; Koenecke, Christian; Cornberg, Markus; Welte, Karl; Blazar, Bruce R.; Sauer, Martin G.

    2009-01-01

    Antigen-presenting cells (APCs) of host origin drive graft-versus-leukemia (GVL) effects but can also trigger life-threatening graft-versus-host disease (GVHD) after hematopoietic cell transplantation (HCT) across major histocompatibility complex (MHC) barriers. We show that in vitro priming of donor lymphocytes can circumvent the need of recipient-derived APCs in vivo for mediating robust GVL effects and significantly diminishes the risk of severe GVHD. In vitro, generated and expanded T cel...

  17. Two-dimensional blue native/SDS-PAGE analysis of whole cell lysate protein complexes of rice in response to salt stress.

    Science.gov (United States)

    Hashemi, Amenehsadat; Gharechahi, Javad; Nematzadeh, Ghorbanali; Shekari, Faezeh; Hosseini, Seyed Abdollah; Salekdeh, Ghasem Hosseini

    2016-08-01

    To understand the biology of a plant in response to stress, insight into protein-protein interactions, which almost define cell behavior, is thought to be crucial. Here, we provide a comparative complexomics analysis of leaf whole cell lysate of two rice genotypes with contrasting responses to salt using two-dimensional blue native/SDS-PAGE (2D-BN/SDS-PAGE). We aimed to identify changes in subunit composition and stoichiometry of protein complexes elicited by salt. Using mild detergent for protein complex solubilization, we were able to identify 9 protein assemblies as hetero-oligomeric and 30 as homo-oligomeric complexes. A total of 20 proteins were identified as monomers in the 2D-BN/SDS-PAGE gels. In addition to identifying known protein complexes that confirm the technical validity of our analysis, we were also able to discover novel protein-protein interactions. Interestingly, an interaction was detected for glycolytic enzymes enolase (ENO1) and triosephosphate isomerase (TPI) and also for a chlorophyll a-b binding protein and RuBisCo small subunit. To show changes in subunit composition and stoichiometry of protein assemblies during salt stress, the differential abundance of interacting proteins was compared between salt-treated and control plants. A detailed exploration of some of the protein complexes provided novel insight into the function, composition, stoichiometry and dynamics of known and previously uncharacterized protein complexes in response to salt stress. Copyright © 2016 Elsevier GmbH. All rights reserved.

  18. Vaccination with autologous dendritic cells pulsed with multiple tumor antigens for treatment of patients with malignant melanoma: results from a phase I/II trial

    DEFF Research Database (Denmark)

    Trepiakas, Redas; Berntsen, Annika; Hadrup, Sine Reker

    2010-01-01

    Dendritic cells are regarded as the most effective antigen presenting cells and coordinators of the immune response and therefore suitable as vaccine basis. Here we present results from a clinical study in which patients with malignant melanoma (MM) with verified progressive disease received...... vaccination with autologous monocyte-derived mature dendritic cells (DC) pulsed with p53, survivin and telomerase-derived peptides (HLA-A2+ patients) or with autologous/allogeneic tumor lysate (HLA-A2(-) patients) in combination with low-dose interleukin (IL)-2 and interferon (IFN)-alpha2b....

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

    Science.gov (United States)

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

    2015-01-01

    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, 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 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 dendritic cells. 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 antigen presenting cells and provide foundational information for the rational design of targeted nanovaccines against HIV-1. PMID:25068589

  20. Antigen cross-priming of cell-associated proteins is enhanced by macroautophagy within the antigen donor cell

    Directory of Open Access Journals (Sweden)

    Matthew eAlbert

    2012-03-01

    Full Text Available Phagocytosis of dying cells constitutes an importance mechanism of antigen capture for the cross-priming of CD8+ T cells. This process has been shown to be critical for achieving tumor and viral immunity. While most studies have focused on the mechanisms inherent in the dendritic cell that account for exogenous antigen accessing MHC I, several recent reports have highlighted the important contribution made by the antigen donor cell. Specifically, the cell stress and cell death pathways that precede antigen transfer are now known to impact cross-presentation and cross-priming. Herein, we review the current literature regarding a role for macro-autophagy within the antigen donor cell. Further examination of this point of immune regulation is warranted and may contribute to a better understanding of how to optimize immunotherapy for treatment of cancer and chronic infectious disease.

  1. Improved efficacy of therapeutic vaccination with dendritic cells pulsed with tumor cell lysate against hepatocellular carcinoma by introduction of 2 tandem repeats of microbial HSP70 peptide epitope 407-426 and OK-432.

    Science.gov (United States)

    Ge, Chiyu; Xing, Yun; Wang, Qi; Xiao, Wen; Lu, Yong; Hu, Xiangbing; Gao, Zhenqiu; Xu, Maolei; Ma, Yanjun; Cao, Rongyue; Liu, Jingjing

    2011-12-01

    Therapeutic vaccination with dendritic cells (DCs) pulsed with tumor cell lysate vaccine (H-D) represents an attractive approach for hepatocellular carcinoma (HCC) treatment. However, the efficacy of this approach is not most satisfactory for the low levels of T helper 1 (Th1)-type cytokines secretion and weak T cell responses. In this study, in order to increase the potency of H-D, two tandem repeats of microbial HSP70 peptide epitope 407-426 (2mHSP70(407-426), M2) which has been demonstrated to be effective in enhancing DC maturation were applied. The DC vaccine (HM-D) which was HCC tumor cell lysate pulsed with M2 was developed. Nevertheless, the immunotherapeutic effect was still not satisfactory enough even some promotion was obtained. Therefore, OK-432 (OK), which is a useful anti-cancer agent and effectively in stimulating DC maturation, was introduced to HM-D. Our results demonstrated that treatment with the improved DC vaccine which was tumor cell lysate pulsed with M2 and OK (HMO-D), compared with H-D and HM-D, significantly increased cell surface markers (MHC-I and II, CD40, CD80, CD86 and CD11c) expression on DCs, enhanced Th1-type cytokines (IL-12, TNF-α and IFN-γ) production but not Th2-type cytokine (IL-5) production, induced remarkable high levels of lymphocytes proliferation and CD8(+) cytotoxic T-lymphocyte (CTL). Furthermore, immunization with HMO-D effectively reduced tumor progression and enhanced the survival of mice with H22 tumors. Besides, we also found that the capability of M2 in inducing the Th1 cytokines was stronger than OK. In view of these results, HMO-D vaccination provided a novel immunotherapeutic approach for the treatment of HCC. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. A high-throughput 2D-analytical technique to obtain single protein parameters from complex cell lysates for in silico process development of ion exchange chromatography.

    Science.gov (United States)

    Kröner, Frieder; Elsäßer, Dennis; Hubbuch, Jürgen

    2013-11-29

    The accelerating growth of the market for biopharmaceutical proteins, the market entry of biosimilars and the growing interest in new, more complex molecules constantly pose new challenges for bioseparation process development. In the presented work we demonstrate the application of a multidimensional, analytical separation approach to obtain the relevant physicochemical parameters of single proteins in a complex mixture for in silico chromatographic process development. A complete cell lysate containing a low titre target protein was first fractionated by multiple linear salt gradient anion exchange chromatography (AEC) with varying gradient length. The collected fractions were subsequently analysed by high-throughput capillary gel electrophoresis (HT-CGE) after being desalted and concentrated. From the obtained data of the 2D-separation the retention-volumes and the concentration of the single proteins were determined. The retention-volumes of the single proteins were used to calculate the related steric-mass action model parameters. In a final evaluation experiment the received parameters were successfully applied to predict the retention behaviour of the single proteins in salt gradient AEC. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Validated hemoglobin-depletion approach for red blood cell lysate proteome analysis by means of 2D PAGE and Orbitrap MS.

    Science.gov (United States)

    Walpurgis, Katja; Kohler, Maxie; Thomas, Andreas; Wenzel, Folker; Geyer, Hans; Schänzer, Wilhelm; Thevis, Mario

    2012-08-01

    The analysis of the cytosolic red blood cell (RBC) proteome is negatively affected by the high intracellular amount of hemoglobin complicating the detection of low-abundant cytosolic proteins. In this study, an alternative approach for the preparation of hemoglobin-depleted RBC lysates is presented, which was established in combination with downstream 2D PAGE analysis and Orbitrap MS. Hemoglobin removal was accomplished by using HemoVoid(TM) depletion reagent, which enabled a very efficient enrichment of low-abundant proteins by simultaneously reducing the hemoglobin concentration of the sample. After defining selected sample preparation protocol characteristics including specificity/selectivity, precision and linearity, a 2D reference map (pH 4-7) of the cytosolic RBC proteome was generated and a total of 189 different proteins were identified. Thus, the presented approach proved to be highly suitable to prepare reproducible high-resolution 2D protein maps of the RBC cytosol and provides a helpful tool for future studies investigating disease- or storage-induced changes of the cytosolic RBC proteome. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Endotoxin, thrombin, and the Limulus amebocyte lysate test.

    Science.gov (United States)

    Yin, E T

    1975-09-01

    The Limulus amebocyte lysate, a proteinaceous composite isolated from the hemolymph cells of the horseshoe crab (Limulus polyphemus) is sensitive to picogram quantities of Gram-negative bacterial lipopolysaccharides. However, a controversy currently exists as to whether the Limulus amebocyte lysate is specifically sensitive to Gram-negative bacterial endotoxins as a result of a recent report that the blood coagulation protease, thrombin, can mimic endotoxins in the Limulus amebocyte lysate test. Experiments including those employing two highly purified fractions isolated from the Limulus lystae have provided us with evidence that thrombin per se is unable to mimic endotoxin.

  5. Microbial lysate upregulates host oxytocin

    Science.gov (United States)

    Varian, Bernard J.; Poutahidis, Theofilos; DiBenedictis, Brett T.; Levkovich, Tatiana; Ibrahim, Yassin; Didyk, Eliska; Shikhman, Lana; Cheung, Harry K.; Hardas, Alexandros; Ricciardi, Catherine E.; Kolandaivelu, Kumaran; Veenema, Alexa H.; Alm, Eric J.; Erdman, Susan E.

    2017-01-01

    Neuropeptide hormone oxytocin has roles in social bonding, energy metabolism, and wound healing contributing to good physical, mental and social health. It was previously shown that feeding of a human commensal microbe Lactobacillus reuteri (L. reuteri) is sufficient to up-regulate endogenous oxytocin levels and improve wound healing capacity in mice. Here we show that oral L. reuteri-induced skin wound repair benefits extend to human subjects. Further, dietary supplementation with a sterile lysate of this microbe alone is sufficient to boost systemic oxytocin levels and improve wound repair capacity. Oxytocin-producing cells were found to be increased in the caudal paraventricular nucleus [PVN] of the hypothalamus after feeding of a sterile lysed preparation of L. reuteri, coincident with lowered blood levels of stress hormone corticosterone and more rapid epidermal closure, in mouse models. We conclude that microbe viability is not essential for regulating host oxytocin levels. The results suggest that a peptide or metabolite produced by bacteria may modulate host oxytocin secretion for potential public or personalized health goals. PMID:27825953

  6. Platelet lysate as a substitute for animal serum for the ex-vivo expansion of mesenchymal stem/stromal cells: present and future.

    Science.gov (United States)

    Astori, Giuseppe; Amati, Eliana; Bambi, Franco; Bernardi, Martina; Chieregato, Katia; Schäfer, Richard; Sella, Sabrina; Rodeghiero, Francesco

    2016-07-13

    The use of fetal bovine serum (FBS) as a cell culture supplement is discouraged by regulatory authorities to limit the risk of zoonoses and xenogeneic immune reactions in the transplanted host. Additionally, FBS production came under scrutiny due to animal welfare concerns. Platelet derivatives have been proposed as FBS substitutes for the ex-vivo expansion of mesenchymal stem/stromal cells (MSCs) since platelet-derived growth factors can promote MSC ex-vivo expansion. Platelet-derived growth factors are present in platelet lysate (PL) obtained after repeated freezing-thawing cycles of the platelet-rich plasma or by applying physiological stimuli such as thrombin or CaCl2.PL-expanded MSCs have been used already in the clinic, taking advantage of their faster proliferation compared with FBS-expanded preparations. Should PL be applied to other biopharmaceutical products, its demand is likely to increase dramatically. The use of fresh platelet units for the production of PL raises concerns due to limited availability of platelet donors. Expired units might represent an alternative, but further data are needed to define safety, including pathogen reduction, and functionality of the obtained PL. In addition, relevant questions concerning the definition of PL release criteria, including concentration ranges of specific growth factors in PL batches for various clinical indications, also need to be addressed. We are still far from a common definition of PL and standardized PL manufacture due to our limited knowledge of the mechanisms that mediate PL-promoting cell growth. Here, we concisely discuss aspects of PL as MSC culture supplement as a preliminary step towards an agreed definition of the required characteristics of PL for the requirements of manufacturers and users.

  7. Phase 1/2 study of immunotherapy with dendritic cells pulsed with autologous tumor lysate in patients with refractory bone and soft tissue sarcoma.

    Science.gov (United States)

    Miwa, Shinji; Nishida, Hideji; Tanzawa, Yoshikazu; Takeuchi, Akihiko; Hayashi, Katsuhiro; Yamamoto, Norio; Mizukoshi, Eishiro; Nakamoto, Yasunari; Kaneko, Shuichi; Tsuchiya, Hiroyuki

    2017-05-01

    There are limited options for the curative treatment of refractory bone and soft tissue sarcomas. The purpose of this phase 1/2 study was to assess the immunological and clinical effects of dendritic cells (DCs) pulsed with autologous tumor lysate (TL) in patients with advanced bone and soft tissue sarcomas. Thirty-seven patients with metastatic or recurrent sarcomas were enrolled in this study. Peripheral blood mononuclear cells obtained from the patients were suspended in media containing interleukin 4 (IL-4) and granulocyte-macrophage colony-stimulating factor. Subsequently, these cells were treated with TL, tumor necrosis factor α, and OK-432. The DCs were injected into the inguinal or axillary region. One treatment course comprised 6 weekly DC injections. The toxicity, clinical response (tumor volume, serum interferon-γ [IFN-γ], and serum IL-12), and oncological outcomes were observed. In total, 47 courses of DC therapy were performed in 37 patients. No severe adverse events or deaths associated with the DC injections were observed in the study patients. Increased serum IFN-γ and IL-12 levels were observed 1 month after the DC injection. Among the 37 patients, 35 patients were assessed for clinical responses: 28 patients showed tumor progression, 6 patients had stable disease, and 1 patient showed a partial response 8 weeks after the DC injection. The 3-year overall and progression-free survival rates of the patients were 42.3% and 2.9%, respectively. Although DC therapy appears safe and resulted in an immunological response in patients with refractory sarcoma, it resulted in an improvement of the clinical outcome in only a small number of patients. Cancer 2017;123:1576-1584. © 2017 American Cancer Society. © 2017 American Cancer Society.

  8. Cell-free antigens of Sporothrix brasiliensis: antigenic diversity and application in an immunoblot assay.

    Science.gov (United States)

    Almeida-Paes, Rodrigo; Bailão, Alexandre Melo; Pizzini, Cláudia Vera; Reis, Rosani Santos; Soares, Célia Maria de Almeida; Peralta, José Mauro; Gutierrez-Galhardo, Maria Clara; Zancopé-Oliveira, Rosely Maria

    2012-11-01

    Sporotrichosis is a subcutaneous mycosis diagnosed by isolation of the fungus in culture. Serological tests for help in diagnosis in general do not use purified or recombinant antigens, because there is a paucity of described immunoreactive proteins, especially for the new described Sporothrix species, such as Sporothrix brasiliensis. This study aims to characterise antigens from S. brasiliensis and verify their application in serodiagnosis of sporotrichosis. An immunoblot assay allied with computer-based analysis was used to identify putative antigenic molecules in a cell-free extracts of both morphological phases of this fungus, and to delineate antigenic polymorphism among seven S. brasiliensis isolates and one S. schenckii Brazilian strain. The mycelial and yeast phase of the fungus originated 14 and 23 reactive bands, respectively, which were variable in intensity. An 85 kDa antigen, verified in the yeast phase of the fungus, was observed in all strains used and the immunodominant protein was identified. This protein, however, cross-react with serum samples from patients infected with other pathogens. The results show that the S. brasiliensis cell-free antigen extract is a single and inexpensive source of antigens, and can be applied on the sporotrichosis serodiagnosis. © 2012 Blackwell Verlag GmbH.

  9. Lipopolysaccharide-binding proteins of Limulus amebocyte lysate.

    OpenAIRE

    Roth, R I; Tobias, P S

    1993-01-01

    Limulus amebocyte lysate, obtained from horseshoe crab (Limulus polyphemus) blood cells, contains a coagulation system which is activated by bacterial lipopolysaccharide (LPS). A chromatographic fraction of Limulus lysate, containing the endotoxin-sensitive factor(s) which initiates the coagulation cascade, was studied. We utilized a photoreactive, cleavable, radiolabeled derivative of Salmonella minnesota LPS, LPS-(p-azidosalicylamido)-1,3'-dithiopropionamide (LPS-ASD), to identify LPS-bindi...

  10. Boosting antibody responses by targeting antigens to dendritic cells.

    Science.gov (United States)

    Caminschi, Irina; Shortman, Ken

    2012-02-01

    Delivering antigens directly to dendritic cells (DCs) in situ, by injecting antigens coupled to antibodies specific for DC surface molecules, is a promising strategy for enhancing vaccine efficacy. Enhanced cytotoxic T cell responses are obtained if an adjuvant is co-administered to activate the DC. Such DC targeting is also effective at enhancing humoral immunity, via the generation of T follicular helper cells. Depending on the DC surface molecule targeted, antibody production can be enhanced even in the absence of adjuvants. In the case of Clec9A as the DC surface target, enhanced antibody production is a consequence of the DC-restricted expression of the target molecule. Few other cells absorb the antigen-antibody construct, therefore, it persists in the bloodstream, allowing sustained antigen presentation, even by non-activated DCs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Safety and complications reporting update on the re-implantation of culture-expanded mesenchymal stem cells using autologous platelet lysate technique.

    Science.gov (United States)

    Centeno, Christopher J; Schultz, John R; Cheever, Michelle; Freeman, Michael; Faulkner, Stephen; Robinson, Brent; Hanson, Ronald

    2011-12-01

    Mesenchymal stem cells (MSCs) hold great promise as therapeutic agents in regenerative medicine. Numerous animal studies have documented the multipotency of MSCs, showing their capabilities for differentiating into orthopedic tissues such as muscle, bone, cartilage, and tendon. However, the safety of culture expanded MSC's for human use has only just begun to be reported. Between 2006 and 2010, two groups of patients were treated for various orthopedic conditions with culture-expanded, autologous, bone marrow-derived MSCs (group 1: n=50; group 2: n=290-one patient in both groups). Cells were cultured in monolayer culture flasks using an autologous platelet lysate technique and re-injected into peripheral joints or into intervertebral discs with use of c-arm fluoroscopy. While both groups had prospective surveillance for complications, Group 1 additionally underwent 3.0T MRI tracking of the re-implant sites. The mean age of patients treated was 53 +/- 13.85 years; 214 were males and 125 females with mean follow-up time from any procedure being 435 days +/- 261 days. Number of contacts initiated based on time from first procedure was 482 at 3 months, 433 at 6 months, 316 contacts at 12 months, 110 contacts at 24 months, and 22 contacts at 36 months. For Group 1, 50 patients underwent 210 MRI surveillance procedures at 3 months, 6 months, 1, 2, and 3 years which failed to demonstrate any tumor formation at the re-implant sites. Formal disease surveillance for adverse events based on HHS criteria documented significantly less morbidity than is commonly reported for more invasive surgical procedures, all of which were either self-limited or were remedied with therapeutic measures. Two patients were diagnosed with cancer out of 339 patients treated since study inception; however, this was almost certainly unrelated to the MSC therapy and the neoplasm rate in similar to that seen in the U.S. Caucasian population. Knee outcome data was collected on a subset of patients

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    -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...... predominantly from differentiation and cancer-testis antigens. Notably, the majority of these responses were of low frequency and tumor-specific T-cell frequencies decreased during rapid expansion. A further notable observation was a large variation in the T-cell specificities detected in cultures established...

  13. Chimeric antigen receptor T-cell therapy for solid tumors

    Directory of Open Access Journals (Sweden)

    Kheng Newick

    2016-01-01

    Full Text Available Chimeric antigen receptor (CAR T cells are engineered constructs composed of synthetic receptors that direct T cells to surface antigens for subsequent elimination. Many CAR constructs are also manufactured with elements that augment T-cell persistence and activity. To date, CAR T cells have demonstrated tremendous success in eradicating hematological malignancies (e.g., CD19 CARs in leukemias. This success is not yet extrapolated to solid tumors, and the reasons for this are being actively investigated. Here in this mini-review, we discuss some of the key hurdles encountered by CAR T cells in the solid tumor microenvironment.

  14. Effective antigen presentation to helper T cells by human eosinophils.

    Science.gov (United States)

    Farhan, Ruhaifah K; Vickers, Mark A; Ghaemmaghami, Amir M; Hall, Andrew M; Barker, Robert N; Walsh, Garry M

    2016-12-01

    Although eosinophils are inflammatory cells, there is increasing attention on their immunomodulatory roles. For example, murine eosinophils can present antigen to CD4 + T helper (Th) cells, but it remains unclear whether human eosinophils also have this ability. This study determined whether human eosinophils present a range of antigens, including allergens, to activate Th cells, and characterized their expression of MHC class II and co-stimulatory molecules required for effective presentation. Human peripheral blood eosinophils purified from non-allergic donors were pulsed with the antigens house dust mite extract (HDM), Timothy Grass extract (TG) or Mycobacterium tuberculosis purified protein derivative (PPD), before co-culture with autologous CD4 + Th cells. Proliferative and cytokine responses were measured, with eosinophil expression of HLA-DR/DP/DQ and the co-stimulatory molecules CD40, CD80 and CD86 determined by flow cytometry. Eosinophils pulsed with HDM, TG or PPD drove Th cell proliferation, with the response strength dependent on antigen concentration. The cytokine responses varied with donor and antigen, and were not biased towards any particular Th subset, often including combinations of pro- and anti-inflammatory cytokines. Eosinophils up-regulated surface expression of HLA-DR/DP/DQ, CD80, CD86 and CD40 in culture, increases that were sustained over 5 days when incubated with antigens, including HDM, or the major allergens it contains, Der p I or Der p II. Human eosinophils can, therefore, act as effective antigen-presenting cells to stimulate varied Th cell responses against a panel of antigens including HDM, TG or PPD, an ability that may help to determine the development of allergic disease. © 2016 John Wiley & Sons Ltd.

  15. Antigen Availability Shapes T Cell Differentiation and Function during Tuberculosis.

    Science.gov (United States)

    Moguche, Albanus O; Musvosvi, Munyaradzi; Penn-Nicholson, Adam; Plumlee, Courtney R; Mearns, Helen; Geldenhuys, Hennie; Smit, Erica; Abrahams, Deborah; Rozot, Virginie; Dintwe, One; Hoff, Søren T; Kromann, Ingrid; Ruhwald, Morten; Bang, Peter; Larson, Ryan P; Shafiani, Shahin; Ma, Shuyi; Sherman, David R; Sette, Alessandro; Lindestam Arlehamn, Cecilia S; McKinney, Denise M; Maecker, Holden; Hanekom, Willem A; Hatherill, Mark; Andersen, Peter; Scriba, Thomas J; Urdahl, Kevin B

    2017-06-14

    CD4 T cells are critical for protective immunity against Mycobacterium tuberculosis (Mtb), the cause of tuberculosis (TB). Yet to date, TB vaccine candidates that boost antigen-specific CD4 T cells have conferred little or no protection. Here we examined CD4 T cell responses to two leading TB vaccine antigens, ESAT-6 and Ag85B, in Mtb-infected mice and in vaccinated humans with and without underlying Mtb infection. In both species, Mtb infection drove ESAT-6-specific T cells to be more differentiated than Ag85B-specific T cells. The ability of each T cell population to control Mtb in the lungs of mice was restricted for opposite reasons: Ag85B-specific T cells were limited by reduced antigen expression during persistent infection, whereas ESAT-6-specific T cells became functionally exhausted due to chronic antigenic stimulation. Our findings suggest that different vaccination strategies will be required to optimize protection mediated by T cells recognizing antigens expressed at distinct stages of Mtb infection. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

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

    2009-01-01

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

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

    DEFF Research Database (Denmark)

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

    1988-01-01

    The processing of a protein antigen is a multi-step event taking place in antigen-presenting cells. Processing is a prerequisite for the recognition of most antigens by T lymphocytes. The antigen is ingested by endocytosis, transported to an acid cellular compartment and subjected to proteolytic...... fragmentation. Some of the antigen fragments bind to MHC class II molecules and are transported to the surface of the antigen-presenting cell where the actual presentation to T lymphocytes occurs. The nature of the processed antigen, how and where it is derived and subsequently becomes associated with MHC...

  18. Transportation of sublingual antigens across sublingual ductal epithelial cells to the ductal antigen-presenting cells in mice.

    Science.gov (United States)

    Nagai, Y; Shiraishi, D; Tanaka, Y; Nagasawa, Y; Ohwada, S; Shimauchi, H; Aso, H; Endo, Y; Sugawara, S

    2015-03-01

    Sublingual immunotherapy (SLIT) has proven to be safe and efficient for the treatment of type I allergies. However, the mechanisms underlying allergen transportation within the sublingual compartment, the localization of antigens, and the identities of the cells responsible for this immunization remain incompletely understood. In this study, we focused on the sublingual ductal system and analysed the localization and transportation of antigens after their sublingual application. In mice given adjuvant-free antigens sublingually, tissues were removed at 0, 0.5, 1, or 2 h after the application and subjected to immunohistochemistry. Cells isolated from the sublingual duct and mucosa were analysed by flow cytometry. Substantial immunoreactivity to ovalbumin (OVA) was evident in sublingual ductal epithelial cells at 30 min and 1 h after sublingual administration of OVA, but it had disappeared at 2 h. The ductal epithelial cells incorporated not only OVA, but also particulate antigens such as latex or silica beads and microbes. MHC class II (MHCII)(+) antigen-presenting cells (APCs) were located around the sublingual ductal system, and MHCII(+) cells were co-localized with, and around, antigen-incorporated sublingual duct cells. CD11b(+) CD11c(-) cells were present among CD45(+) MHCII(+) cells at greater frequency in the sublingual duct than in the sublingual mucosa, and they were the main contributors to the incorporation of OVA in vitro. This study reveals that sublingual antigens can be transported across sublingual ductal epithelial cells to the ductal APCs. If the system is the same in humans as in mice, the ductal APCs may prove to be important target cells for SLIT. © 2014 John Wiley & Sons Ltd.

  19. Analysis of cell surface antigens by Surface Plasmon Resonance imaging

    NARCIS (Netherlands)

    Stojanovic, Ivan; Schasfoort, Richardus B.M.; Terstappen, Leonardus Wendelinus Mathias Marie

    2013-01-01

    Surface Plasmon Resonance (SPR) is most commonly used to measure bio-molecular interactions. SPR is used significantly less frequent for measuring whole cell interactions. Here we introduce a method to measure whole cells label free using the specific binding of cell surface antigens expressed on

  20. HLA-DR antigen detection in giant cell lesions.

    Science.gov (United States)

    Regezi, J A; Zarbo, R J; Lloyd, R V

    1986-09-01

    Sixty-six giant cell lesions ranging from inflammatory to neoplastic were evaluated for HLA-DR antigens using formalin/paraffin tissue and a monoclonal antibody labelled by the avidin-biotin peroxidase. HLA-DR antigens were expressed in nearly all lesions, predominantly on round, macrophage-like cells. Granulomatous inflammatory lesions were generally more immunoreactive than non-inflammatory lesions. Multinucleate giant cells were relatively unreactive in non-inflammatory lesions as compared to inflammatory lesions. Determination of HLA-DR expression does not appear to be helpful in discriminating between the various giant cell lesions.

  1. Cell-to-Cell Transfer of M. tuberculosis Antigens Optimizes CD4 T Cell Priming

    Science.gov (United States)

    Srivastava, Smita; Ernst, Joel D.

    2014-01-01

    SUMMARY During Mycobacterium tuberculosis and other respiratory infections, optimal T cell activation requires pathogen transport from the lung to a local draining lymph node (LN). However, the infected inflammatory monocyte-derived dendritic cells (DCs) that transport M. tuberculosis to the local lymph node are relatively inefficient at activating CD4 T cells, possibly due to bacterial inhibition of antigen presentation. We found that infected migratory DCs release M. tuberculosis antigens as soluble, unprocessed proteins for uptake and presentation by uninfected resident lymph node DCs. This transfer of bacterial proteins from migratory to local DCs results in optimal priming of antigen-specific CD4 T cells, which are essential in controlling tuberculosis. Additionally, this mechanism does not involve transfer of the whole bacterium and is distinct from apoptosis or exosome shedding. These findings reveal a mechanism that bypasses pathogen inhibition of antigen presentation by infected cells and generates CD4 T cell responses that control the infection. PMID:24922576

  2. Matrix Metalloproteinase-2, Squamous Cell Carcinoma Antigen, and Tissue Polypeptide-Specific Antigen Expression in Egyptian Patients with Cervical Carcinoma: Relationship with Prognosis

    Directory of Open Access Journals (Sweden)

    Maha Imam Ahmed

    2004-01-01

    Full Text Available Matrix metalloproteinases (MMPs, a family of proteolytic enzymes produced by both stromal and tumor cells, appear to have a key role in the events leading to local invasion and metastasis by malignant neoplasms. In the present study, we evaluated the role of MMP-2, squamous cell carcinoma antigen (SCCA, and tissue polypeptide – specific antigen (TPS in cervical neoplasia. Using Western blotting and enzyme immunoassay (EIA, we analyzed 50 patients with cervical carcinoma (CC and 25 normal controls for expression of MMP-2 in tissue cell lysates. We also quantified SCCA and TPS with microparticle immunoassay and EIA, respectively. The results were correlated with human papilloma virus (HPV infection, clinicopathological findings, and disease outcome. The cutoff point for each marker was estimated from receiver operating characteristic curves. Logistic regression analysis was performed to estimate the odds ratio (OR and 95% confidence interval (CI for each marker. MMP-2, SCCA, and TPS protein expression were significantly higher in patients with CC than in normal controls. While TPS was the best marker for discriminating between patients and controls, MMP-2 was associated with an advanced tumor stage (OR, 13.9 [95% CI, 1.4-133.9] and poor histological grade (OR, 10.2 [95% CI, 1.7-60.5]. Moreover, independent of the effect of an advanced CC stage and grade, the patients' age, and the presence of HPV infection, MMP-2 was considered a strong predictor for CC recurrence (OR, 8.1 [95% CI, 1.3- 49.1]. Tissue markers may be used to select high-risk patients for early detection of and adjuvant therapy for recurrence. Our MMP-2 findings are particularly relevant to the development of protease inhibitors as a new cancer therapy approach.

  3. T-cell target antigens across major gynecologic cancers.

    Science.gov (United States)

    Rodriguez-Garcia, Alba; Minutolo, Nicholas G; Robinson, John M; Powell, Daniel J

    2017-06-01

    Immunotherapies have achieved remarkable success in treating different forms of cancer including melanoma, non-small cell lung carcinoma, bladder cancer, synovial cell sarcoma, and multiple myeloma using immune checkpoint blockade or gene-engineered T-cells. Although gynecologic cancers have not been historically classified as immunogenic tumors, growing evidence has shown that they are in fact able to elicit endogenous antitumor immune responses suggesting that patients with these cancers may benefit from immunotherapy. Modest clinical success has been accomplished in early trials using immunotherapeutic modalities for major gynecologic cancers including ovarian, cervical, and endometrial cancer. Unlike solid cancers with high mutational burdens, or hematologic malignancies where target antigens are expressed homogenously and exclusively by tumor cells, identifying tumor-restricted antigens has been challenging when designing a T-cell targeted therapy for gynecologic tumors. Nevertheless, mounting preclinical and clinical evidence suggests that targeting shared, viral or patient-specific mutated antigens expressed by gynecologic tumors with T-cells may improve patient outcome. Here we review the strengths and weaknesses of targeting these various antigens, as well as provide insight into the future of immunotherapy for gynecologic cancers. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Elutriated lymphocytes for manufacturing chimeric antigen receptor T cells

    OpenAIRE

    Stroncek, David F.; Lee, Daniel W.; Ren, Jiaqiang; Sabatino, Marianna; Highfill, Steven; Khuu, Hanh; Shah, Nirali N.; Kaplan, Rosandra N.; Fry, Terry J.; Mackall, Crystal L.

    2017-01-01

    Background Clinical trials of Chimeric Antigen Receptor (CAR) T cells manufactured from autologous peripheral blood mononuclear cell (PBMC) concentrates for the treatment of hematologic malignancies have been promising, but CAR T cell yields have been variable. This variability is due in part to the contamination of the PBMC concentrates with monocytes and granulocytes. Methods Counter-flow elutriation allows for the closed system separation of lymphocytes from monocytes and granulocytes. We ...

  5. 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.

  6. Macropinocytosis in phagocytes: regulation of MHC class-II-restricted antigen presentation in dendritic cells

    OpenAIRE

    Liu, Zhenzhen; Roche, Paul A.

    2015-01-01

    AbstractDendritic cells (DCs) are outstanding antigen presenting cells (APCs) due to their robust ability to internalize extracellular antigens using endocytic processes such as receptor-mediated endocytosis, phagocytosis, and macropinocytosis. Macropinocytosis mediates the non-specific uptake of soluble antigens and occurs in DCs constitutively. Macropinocytosis plays a key role in DC-mediated antigen presentation to T cells against pathogens and the efficiency of macropinocytosis in antigen...

  7. High-affinity memory B cells induced by conjugate vaccines against weak tumor antigens are vulnerable to nonconjugated antigen.

    Science.gov (United States)

    Savelyeva, Natalia; Shipton, Michael; Suchacki, Amy; Babbage, Gavin; Stevenson, Freda K

    2011-07-21

    Induction of antibody-mediated immunity against hematologic malignancies requires CD4(+) T-cell help, but weak tumor antigens generally fail to induce adequate T-cell responses, or to overcome tolerance. Conjugate vaccines can harness alternative help to activate responses, but memory B cells may then be exposed to leaking tumor-derived antigen without CD4(+) T-cell support. We showed previously using lymphoma-derived idiotypic antigen that exposure to "helpless" antigen silences the majority of memory IgG(+) B cells. Transfer experiments now indicate that silencing is permanent. In marked contrast to IgG, most coexisting IgM(+) memory B cells exposed to "helpless" antigen survive. Confirmation in a hapten (NP) model allowed measurement of affinity, revealing this, rather than isotype, as the determinant of survival. IgM(+) B cells had Ig variable region gene usage similar to IgG but with fewer somatic mutations. Survival of memory B cells appears variably controlled by affinity for antigen, allowing a minority of low affinity IgG(+), but most IgM(+), memory B cells to escape deletion in the absence of T-cell help. The latter remain, but the majority fail to undergo isotype switch. These findings could apply to other tumor antigens and are relevant for vaccination strategies aimed to induce long-term antibody.

  8. The activation of the adaptive immune system: cross-talk between antigen-presenting cells, T cells and B cells.

    Science.gov (United States)

    den Haan, Joke M M; Arens, Ramon; van Zelm, Menno C

    2014-12-01

    The adaptive immune system consists of T and B cells that express clonally distributed antigen receptors. To achieve functional adaptive immune responses, antigen-specific T cell populations are stimulated by professional antigen-presenting cells like dendritic cells (DCs), which provide crucial stimulatory signals for efficient expansion and development of effector functions. Antigen-specific B cells receive costimulatory signals from helper T cells to stimulate affinity maturation and isotype switching. Here we elaborate on the interactions between DCs, T cells and B cells, and on the important signals for efficient induction of adaptive immune responses. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. A novel recycling mechanism of native IgE-antigen complexes in human B cells facilitates transfer of antigen to dendritic cells for antigen presentation.

    Science.gov (United States)

    Engeroff, Paul; Fellmann, Marc; Yerly, Daniel; Bachmann, Martin F; Vogel, Monique

    2017-10-23

    IgE-immune complexes (IgE-ICs) have been shown to enhance antibody and T-cell responses in mice by targeting CD23 (FcεRII), the low-affinity receptor for IgE on B cells. In humans, the mechanism by which CD23-expressing cells take up IgE-ICs and process them is not well understood. To investigate this question, we compared the fate of IgE-ICs in human B cells and in CD23-expressing monocyte-derived dendritic cells (moDCs) that represent classical antigen-presenting cells and we aimed at studying IgE-dependent antigen presentation in both cell types. B cells and monocytes were isolated from peripheral blood, and monocytes were differentiated into moDCs. Both cell types were stimulated with IgE-ICs consisting of 4-hydroxy-3-iodo-5-nitrophenylacetyl (NIP)-specific IgE JW8 and NIP-BSA to assess binding, uptake, and degradation dynamics. To assess CD23-dependent T-cell proliferation, B cells and moDCs were pulsed with IgE-NIP-tetanus toxoid complexes and cocultured with autologous T cells. IgE-IC binding was CD23-dependent in B cells, and moDCs and CD23 aggregation, as well as IgE-IC internalization, occurred in both cell types. Although IgE-ICs were degraded in moDCs, B cells did not degrade the complexes but recycled them in native form to the cell surface, enabling IgE-IC uptake by moDCs in cocultures. The resulting proliferation of specific T cells was dependent on cell-cell contact between B cells and moDCs, which was explained by increased upregulation of costimulatory molecules CD86 and MHC class II on moDCs induced by B cells. Our findings argue for a novel model in which human B cells promote specific T-cell proliferation on IgE-IC encounter. On one hand, B cells act as carriers transferring antigen to more efficient antigen-presenting cells such as DCs. On the other hand, B cells can directly promote DC maturation and thereby enhance T-cell stimulation. Copyright © 2017. Published by Elsevier Inc.

  10. Virosome-mediated delivery of protein antigens to dendritic cells

    NARCIS (Netherlands)

    Bungener, L; Serre, K; Bijl, L; Leserman, L; Wilschut, J; Daemen, T; Machy, P

    2002-01-01

    Virosomes are reconstituted viral membranes in which protein can be encapsulated. Fusion-active virosomes, fusion-inactive virosomes and liposomes were used to study the conditions needed for delivery of encapsulated protein antigen ovalbumin (OVA) to dendritic cells (DCs) for MHC class I and 11

  11. Vaccination of B-CLL patients with autologous dendritic cells can change the frequency of leukemia antigen-specific CD8+ T cells as well as CD4+CD25+FoxP3+ regulatory T cells toward an antileukemia response.

    Science.gov (United States)

    Hus, I; Schmitt, M; Tabarkiewicz, J; Radej, S; Wojas, K; Bojarska-Junak, A; Schmitt, A; Giannopoulos, K; Dmoszyńska, A; Roliński, J

    2008-05-01

    Recently, we described that vaccination with allogeneic dendritic cells (DCs) pulsed with tumor cell lysate generated specific CD8+ T cell response in patients with B-cell chronic lymphocytic leukemia (B-CLL). In the present study, the potential of autologous DCs pulsed ex vivo with tumor cell lysates to stimulate antitumor immunity in patients with B-CLL in early stages was evaluated. Twelve patients at clinical stage 0-2 as per Rai were vaccinated intradermally up to eight times with a mean number of 7.4 x 10(6) DCs pulsed with B-CLL cell lysate. We observed a decrease of peripheral blood leukocytes and CD19+/CD5+ leukemic cells in five patients, three patients showed a stable disease and four patients progressed despite DC vaccination. A significant increase of specific cytotoxic CD8+ T lymphocytes against the leukemia-associated antigens RHAMM or fibromodulin was detected in four patients after DC vaccination. In patients with a clinical response, an increase of interleukin 12 (IL-12) serum levels and a decrease of the frequency of CD4+CD25(+)FOXP3+ T regulatory cells were observed. Taken together, the study demonstrated that vaccination with autologous DC in CLL patients is feasible and safe. Immunological and to some extend hematological responses could be noted, justifying further investigation on this immunotherapeutical approach.

  12. Out-of-plane integration of a multimode optical fiber for single particle/cell detection at multiple points on a microfluidic device with applications to particle/cell counting, velocimetry, size discrimination and the analysis of single cell lysate injections.

    Science.gov (United States)

    Sadeghi, Jalal; Patabadige, Damith E W; Culbertson, Anne H; Latifi, Hamid; Culbertson, Christopher T

    2016-12-20

    In this paper a single particle/cell-tracking microfluidic device that integrates an out-of-plane multimode optical fiber (OP-MMF) is reported. This OP-MMF is used to generate three excitation light-lines and three detection spots using only one excitation source and one detector. It takes advantage of an optical tunneling mode to create two excitation lines in a microfluidic channel emanating from a single fiber end. This method was used to accurately count particles/cells and perform velocity measurements and size discrimination. The velocity and size distributions of 5, 7, and 10 μm fluorescently labeled polystyrene beads were determined using the OP-MMF. Additionally, this method was used to analyze cell lysates with the third excitation line in the separation channel. The OP-MMF setup accurately detected an intact cell twice ∼2 mm prior to lysis, determined its velocity, and detected the injected cell lysate 3 mm downstream of the injection point in the separation channel. Using this setup, the velocity of cells entering the lysis intersection and the absolute migration times of fluorescently labeled analytes injected into the separation channel were determined in an automated fashion. This method enabled us to determine a lysing/injection efficiency coefficient (K) using signals from the injected lysate signal and from the intact cell before lysing. K provided a reliable measurement of the amount of cell lysate that was injected into the separation channel. The approach reported here could be used in the future to track particles, cells or droplets in a variety of existing microfluidic devices without the need for multiplexed masks, layers, bulky optical elements or complex optical designs.

  13. T cell antigen receptor activation and actin cytoskeleton remodeling

    Science.gov (United States)

    Kumari, Sudha; Curado, Silvia; Mayya, Viveka

    2013-01-01

    T cells constitute a crucial arm of the adaptive immune system and their optimal function is required for a healthy immune response. After the initial step of T cell-receptor (TCR) triggering by antigenic peptide complexes on antigen presenting cell (APC), the T cell exhibits extensive cytoskeletal remodeling. This cytoskeletal remodeling leads to formation of an “immunological synapse” [1] characterized by regulated clustering, segregation and movement of receptors at the interface. Synapse formation regulates T cell activation and response to antigenic peptides and proceeds via feedback between actin cytoskeleton and TCR signaling. Actin polymerization participates in various events during the synapse formation, maturation, and eventually its disassembly. There is increasing knowledge about the actin effectors that couple TCR activation to actin rearrangements [2, 3], and how defects in these effectors translate into impairment of T cell activation. In this review we aim to summarize and integrate parts of what is currently known about this feedback process. In addition, in light of recent advancements in our understanding of TCR triggering and translocation at the synapse, we speculate on the organizational and functional diversity of microfilament architecture in the T cell. PMID:23680625

  14. Modulation of antigen presenting cell functions during chronic HPV infection

    Directory of Open Access Journals (Sweden)

    Abate Assefa Bashaw

    2017-12-01

    Full Text Available High-risk human papillomaviruses (HR-HPV infect basal keratinocytes, where in some individuals they evade host immune responses and persist. Persistent HR-HPV infection of the cervix causes precancerous neoplasia that can eventuate in cervical cancer. Dendritic cells (DCs are efficient in priming/cross-priming antigen-specific T cells and generating antiviral and antitumor cytotoxic CD8+ T cells. However, HR-HPV have adopted various immunosuppressive strategies, with modulation of DC function crucial to escape from the host adaptive immune response. HPV E6 and E7 oncoproteins alter recruitment and localization of epidermal DCs, while soluble regulatory factors derived from HPV-induced hyperplastic epithelium change DC development and influence initiation of specific cellular immune responses. This review focuses on current evidence for HR-HPV manipulation of antigen presentation in dendritic cells and escape from host immunity.

  15. MHC class II antigen presentation by B cells in health and disease

    NARCIS (Netherlands)

    Souwer, Yuri

    2009-01-01

    MHC class II antigen presentation by B cells is important to activate CD4+ T cells that stimulate the B cell to produce antibodies. Besides this, disruption of MHC class II antigen presentation could play a role in immune escape by tumor cells. This thesis describes MHC class II antigen presentation

  16. 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....

  17. Anti-immunoglobulin augments the B-cell antigen-presentation function independently of internalization of receptor-antigen complex.

    OpenAIRE

    Casten, L A; Lakey, E K; Jelachich, M L; Margoliash, E; Pierce, S K

    1985-01-01

    All mouse splenic B cells, including small resting B cells, process and present the native globular protein antigens, pigeon and tobacco hornworm moth cytochromes c, to a cytochrome c-specific T-cell hybrid in a major histocompatibility complex-restricted fashion, in the micromolar to nanomolar antigen-concentration range. As is the case for macrophages, treatment with paraformaldehyde or the lysosomotropic agents chloroquine and ammonium chloride blocked processing of the native pigeon prote...

  18. Cell-wall composition and the grouping antigens of Streptococci.

    Science.gov (United States)

    SLADE, H D; SLAMP, W C

    1962-08-01

    Slade, Hutton D. (Northwestern University Medical School, Chicago, Ill.) and William C. Slamp. Cell-wall composition and grouping antigens of streptococci. J. Bacteriol. 84:345-351. 1962.-The carbohydrates present in the cell walls of streptococci belonging to serological groups A-H and K-S, and unclassifiable strains, have been identified. The sugars found were rhamnose, glucose, galactose, arabinose, and mannose. All sugars vary considerably in their distribution among the groups; glucose, galactose, and rhamnose occur most frequently. Strains were found which contained each of the latter sugars singly or in combination with one or both of the other sugars. Variation within a single group occurred in one-half of the groups. A strain containing only glucose and another only galactose were found. Except for groups A and C, in which only rhamnose is present in the great majority of strains, the presence or absence of the sugars does not aid in the identification of the groups. The cell walls of all groups examined also contained alanine, glutamic acid, lysine, glucosamine, galactosamine, and muramic acid. The cell walls of all groups, except D, agglutinated in the presence of specific group antisera, indicating the presence of the group antigen in the cell wall. Strains in groups F, K, and M gave a weak reaction. The structure and chemical composition of the group antigens of the streptococci are discussed.

  19. CARbodies: Human Antibodies Against Cell Surface Tumor Antigens Selected From Repertoires Displayed on T Cell Chimeric Antigen Receptors

    Directory of Open Access Journals (Sweden)

    Vanesa Alonso-Camino

    2013-01-01

    Full Text Available A human single-chain variable fragment (scFv antibody library was expressed on the surface of human T cells after transduction with lentiviral vectors (LVs. The repertoire was fused to a first-generation T cell receptor ζ (TCRζ-based chimeric antigen receptor (CAR. We used this library to isolate antibodies termed CARbodies that recognize antigens expressed on the tumor cell surface in a proof-of-principle system. After three rounds of activation-selection there was a clear repertoire restriction, with the emergence dominant clones. The CARbodies were purified from bacterial cultures as soluble and active proteins. Furthermore, to validate its potential application for adoptive cell therapy, human T cells were transduced with a LV encoding a second-generation costimulatory CAR (CARv2 bearing the selected CARbodies. Transduced human primary T cells expressed significant levels of the CARbodies-based CARv2 fusion protein on the cell surface, and importantly could be specifically activated, after stimulation with tumor cells. This approach is a promising tool for the generation of antibodies fully adapted to the display format (CAR and the selection context (cell synapse, which could extend the scope of current adoptive cell therapy strategies with CAR-redirected T cells.

  20. Adoptive cancer immunotherapy using DNA-demethylated T helper cells as antigen-presenting cells

    DEFF Research Database (Denmark)

    Kirkin, Alexei F.; Dzhandzhugazyan, Karine N.; Guldberg, Per

    2018-01-01

    In cancer cells, cancer/testis (CT) antigens become epigenetically derepressed through DNA demethylation and constitute attractive targets for cancer immunotherapy. Here we report that activated CD4+ T helper cells treated with a DNA-demethylating agent express a broad repertoire of endogenous CT...... antigens and can be used as antigen-presenting cells to generate autologous cytotoxic T lymphocytes (CTLs) and natural killer cells. In vitro, activated CTLs induce HLA-restricted lysis of tumor cells of different histological types, as well as cells expressing single CT antigens. In a phase 1 trial of 25...... patients with recurrent glioblastoma multiforme, cytotoxic lymphocytes homed to the tumor, with tumor regression ongoing in three patients for 14, 22, and 27 months, respectively. No treatment-related adverse effects were observed. This proof-of-principle study shows that tumor-reactive effector cells can...

  1. Lym-1 Chimeric Antigen Receptor T Cells Exhibit Potent Anti-Tumor Effects against B-Cell Lymphoma

    OpenAIRE

    Long Zheng; Peisheng Hu; Brandon Wolfe; Caryn Gonsalves; Luqing Ren; Leslie A. Khawli; Harvey R. Kaslow; Alan L. Epstein

    2017-01-01

    T cells expressing chimeric antigen receptors (CARs) recognizing CD19 epitopes have produced remarkable anti-tumor effects in patients with B-cell malignancies. However, cancer cells lacking recognized epitopes can emerge, leading to relapse and death. Thus, CAR T cells targeting different epitopes on different antigens could improve immunotherapy. The Lym-1 antibody targets a conformational epitope of Human Leukocyte Antigen-antigen D Related (HLA-DR) on the surface of human B-cell lymphomas...

  2. Microfluidic squeezing for intracellular antigen loading in polyclonal B-cells as cellular vaccines

    Science.gov (United States)

    Lee Szeto, Gregory; van Egeren, Debra; Worku, Hermoon; Sharei, Armon; Alejandro, Brian; Park, Clara; Frew, Kirubel; Brefo, Mavis; Mao, Shirley; Heimann, Megan; Langer, Robert; Jensen, Klavs; Irvine, Darrell J.

    2015-05-01

    B-cells are promising candidate autologous antigen-presenting cells (APCs) to prime antigen-specific T-cells both in vitro and in vivo. However to date, a significant barrier to utilizing B-cells as APCs is their low capacity for non-specific antigen uptake compared to “professional” APCs such as dendritic cells. Here we utilize a microfluidic device that employs many parallel channels to pass single cells through narrow constrictions in high throughput. This microscale “cell squeezing” process creates transient pores in the plasma membrane, enabling intracellular delivery of whole proteins from the surrounding medium into B-cells via mechano-poration. We demonstrate that both resting and activated B-cells process and present antigens delivered via mechano-poration exclusively to antigen-specific CD8+T-cells, and not CD4+T-cells. Squeezed B-cells primed and expanded large numbers of effector CD8+T-cells in vitro that produced effector cytokines critical to cytolytic function, including granzyme B and interferon-γ. Finally, antigen-loaded B-cells were also able to prime antigen-specific CD8+T-cells in vivo when adoptively transferred into mice. Altogether, these data demonstrate crucial proof-of-concept for mechano-poration as an enabling technology for B-cell antigen loading, priming of antigen-specific CD8+T-cells, and decoupling of antigen uptake from B-cell activation.

  3. Cultivation and irradiation of human fibroblasts in a medium enriched with platelet lysate for obtaining feeder layer in epidermal cell culture; Cultivo e irradiacao de fibroblastos humanos em meio enriquecido com lisado de plaquetas para obtencao de camada de sustentacao em culturas de celulas da epiderme

    Energy Technology Data Exchange (ETDEWEB)

    Yoshito, Daniele

    2011-07-01

    For over 30 years, the use of culture medium, enriched with bovine serum, and murines fibroblasts, with the rate of proliferation controlled by irradiation or by share anticarcinogenic drugs, has been playing successfully its role in assisting in the development of keratinocytes in culture, for clinical purposes. However, currently there is a growing concern about the possibility of transmitting prions and animals viruses to transplanted patients. Taking into account this concern, the present work aims to cultivate human fibroblasts in a medium enriched with human platelets lysate and determine the irradiation dose of these cells, for obtaining feeder layer in epidermal cell culture. For carrying out the proposed objective, platelets lysis has standardized, this lysate was used for human fibroblasts cultivation and the irradiation dose enough to inhibit its duplication was evaluated. Human keratinocytes were cultivated in these feeder layers, in culture medium enriched with the lysate. With these results we conclude that the 10% platelets lysate promoted a better adhesion and proliferation of human fibroblasts and in all dose levels tested (60 to 300 Gy), these had their mitotic activity inactivated by ionizing irradiation, being that the feeder layers obtained with doses from 70 to 150 Gy were those that provided the best development of keratinocytes in medium containing 2.5% of human platelet lysate. Therefore, it was possible to standardize both the cultivation of human fibroblasts as its inactivation for use as feeder layer in culture of keratinocytes, so as to eliminate xenobiotics components. (author)

  4. Mature IgM-expressing plasma cells sense antigen and develop competence for cytokine production upon antigenic challenge

    Science.gov (United States)

    Blanc, Pascal; Moro-Sibilot, Ludovic; Barthly, Lucas; Jagot, Ferdinand; This, Sébastien; de Bernard, Simon; Buffat, Laurent; Dussurgey, Sébastien; Colisson, Renaud; Hobeika, Elias; Fest, Thierry; Taillardet, Morgan; Thaunat, Olivier; Sicard, Antoine; Mondière, Paul; Genestier, Laurent; Nutt, Stephen L.; Defrance, Thierry

    2016-01-01

    Dogma holds that plasma cells, as opposed to B cells, cannot bind antigen because they have switched from expression of membrane-bound immunoglobulins (Ig) that constitute the B-cell receptor (BCR) to production of the secreted form of immunoglobulins. Here we compare the phenotypical and functional attributes of plasma cells generated by the T-cell-dependent and T-cell-independent forms of the hapten NP. We show that the nature of the secreted Ig isotype, rather than the chemical structure of the immunizing antigen, defines two functionally distinct populations of plasma cells. Fully mature IgM-expressing plasma cells resident in the bone marrow retain expression of a functional BCR, whereas their IgG+ counterparts do not. Antigen boost modifies the gene expression profile of IgM+ plasma cells and initiates a cytokine production program, characterized by upregulation of CCL5 and IL-10. Our results demonstrate that IgM-expressing plasma cells can sense antigen and acquire competence for cytokine production upon antigenic challenge. PMID:27924814

  5. Rational combinations of in vivo cancer antigen priming and adoptive T-cell therapy mobilize immune and clinical responses in terminal cancers.

    Science.gov (United States)

    Ruan, Qing Zhao; Fu, Jian Qian; Wu, Xiao Xuan; Huang, Li Ping; Ruan, Run Sheng

    2018-03-06

    It is now recognized that solid tumors encroach on the host's immune microenvironment to favor its own proliferation. Strategies to enhance the specificity of the endogenous T-cell population against tumors have been met with limited clinical success. We aimed to devise a two-tier protocol coupling in vivo whole antigen priming with ex vivo cellular expansion to clinically evaluate survival in patients following re-infusion of primed, autologous T cells, thereby determining treatment efficacy. Treatment commenced with the acquisition of whole tumor antigens from tumor cell lines corresponding with patients' primary malignancy. Lysate mixture was inoculated intradermally, while peripheral blood mononuclear cells (PBMCs) were periodically extracted via phlebotomy and expanded in culture ex vivo for re-infusion. Post-treatment tumor-specific T-cell response and cytotoxicity was confirmed via Elispot and real-time cell analyzing (RTCA) assay. Serum cytokine levels and cytotoxicity scores were evaluated for associations with survival status and duration. There was a significant increase in cytotoxicity exhibited by T cells measured using both Elispot and RTCA following treatment. Correlation analysis determined significant association between higher post-treatment cytotoxicity scores and survival status (R = 0.52, p = 0.0028) as well as longer survival duration in months (R = 0.59, p = 0.005). Our treatment protocol successfully demonstrated significant correlation between tumor-associated antigen-specific immune response and objective prolongation of survival. Whole-cell cancer antigen priming and adoptive T-cell therapy is, therefore, a highly feasible clinical model which can be easily replicated to positively influence outcome in end-stage malignancy.

  6. The Diagnostic Value of Carcinoembryonic Antigen and Squamous Cell Carcinoma Antigen in Lung Adenosquamous Carcinoma.

    Science.gov (United States)

    Jin, Xiangyu; Xu, Xiaoling; Xu, Haimiao; Lv, Lei; Lu, Hongyang

    2017-04-01

    Lung adenosquamous carcinoma (ASC) is a rare malignant tumor with an adenocarcinoma and a squamous cell carcinoma component and associated with a lower 5-year survival rate than lung squamous cell carcinoma and lung adenocarcinoma. Surgical specimen histology revealed the inadequacy of conventional transbronchial needle aspiration samples in the diagnosis of lung ASC. Most lung ASC patients are not suitable to receive surgery, and it is difficult to diagnose ASC. This study is to explore the possibility of using serum carcinoembryonic antigen (CEA) and squamous cell carcinoma antigen (SCC) as a supplementary diagnostic test for ASC. We retrospectively analyzed the preoperative serum CEA and SCC levels in 34 patients with lung ASC, 35 cases of lung adenocarcinoma patients, 35 cases of lung squamous cell carcinoma patients. 36 cases of lung benign disease patients and 35 cases of healthy people as a control group were also retrospectively collected and analyzed from January 2012 to December 2014 at the Zhejiang Cancer Hospital, China. The differences of CEA and SCC among the groups were evaluated, and the area under the curve (AUC), sensitivity, and specificity were calculated. The levels of SCC and CEA in the lung ASC group were significantly higher than those in the healthy control group and benign disease group (p < 0.05). The SCC level in lung ASC group was significantly higher than that in lung adenocarcinoma group (p < 0.05). CEA and SCC had good diagnostic sensitivity and specificity compared with the healthy control group, and the difference was statistically significant (p < 0.05). Our retrospective study suggested a role for serum CEA and SCC levels as reference markers in the diagnosis of lung ASC. Patients with elevated CEA and SCC levels and diagnosed as lung adenocarcinoma by limited biopsy materials should be offered further work-up to reach an accurate diagnosis and treatment.

  7. Oligopeptide antigens of the angiotensin lineage compete for presentation by paraformaldehyde-treated accessory cells to T cells

    DEFF Research Database (Denmark)

    Buus, S; Werdelin, O

    1986-01-01

    The heptapeptide antigen angiotensin III can be presented to guinea pig T cells by paraformaldehyde-treated antigen-presenting cells, which are incapable of processing antigens and presumably cannot even ingest them. We demonstrate here that the decapeptide angiotensin I can outcompete angiotensin...... III for presentation by paraformaldehyde-treated antigen-presenting cells. It seems likely that the competition is for a site on the surface of the presenting cell. This extends earlier findings of competition for presentation between antigens. We also demonstrate that the antigens of the angiotensin...

  8. Healthy human T-Cell Responses to Aspergillus fumigatus antigens.

    Directory of Open Access Journals (Sweden)

    Neelkamal Chaudhary

    2010-02-01

    Full Text Available Aspergillus fumigatus is associated with both invasive and allergic pulmonary diseases, in different hosts. The organism is inhaled as a spore, which, if not cleared from the airway, germinates into hyphal morphotypes that are responsible for tissue invasion and resultant inflammation. Hyphae secrete multiple products that function as antigens, evoking both a protective (T(H1-T(H17 and destructive allergic (T(H2 immunity. How Aspergillus allergens (Asp f proteins participate in the development of allergic sensitization is unknown.To determine whether Asp f proteins are strictly associated with T(H2 responses, or represent soluble hyphal products recognized by healthy hosts, human T cell responses to crude and recombinant products were characterized by ELISPOT. While responses (number of spots producing IFN-gamma, IL-4 or IL-17 to crude hyphal antigen preparations were weak, responses to recombinant Asp f proteins were higher. Recombinant allergens stimulated cells to produce IFN-gamma more so than IL-4 or IL-17. Volunteers exhibited a diverse CD4+ and CD8+ T cell antigen recognition profile, with prominent CD4 T(H1-responses to Asp f3 (a putative peroxismal membrane protein, Asp f9/16 (cell wall glucanase, Asp f11 (cyclophilin type peptidyl-prolyl isomerase and Asp f22 (enolase. Strong IFN-gamma responses were reproduced in most subjects tested over 6 month intervals.Products secreted after conidial germination into hyphae are differentially recognized by protective T cells in healthy, non-atopic individuals. Defining the specificity of the human T cell repertoire, and identifying factors that govern early responses may allow for development of novel diagnostics and therapeutics for both invasive and allergic Aspergillus diseases.

  9. Healthy human T-Cell Responses to Aspergillus fumigatus antigens.

    Science.gov (United States)

    Chaudhary, Neelkamal; Staab, Janet F; Marr, Kieren A

    2010-02-17

    Aspergillus fumigatus is associated with both invasive and allergic pulmonary diseases, in different hosts. The organism is inhaled as a spore, which, if not cleared from the airway, germinates into hyphal morphotypes that are responsible for tissue invasion and resultant inflammation. Hyphae secrete multiple products that function as antigens, evoking both a protective (T(H)1-T(H)17) and destructive allergic (T(H)2) immunity. How Aspergillus allergens (Asp f proteins) participate in the development of allergic sensitization is unknown. To determine whether Asp f proteins are strictly associated with T(H)2 responses, or represent soluble hyphal products recognized by healthy hosts, human T cell responses to crude and recombinant products were characterized by ELISPOT. While responses (number of spots producing IFN-gamma, IL-4 or IL-17) to crude hyphal antigen preparations were weak, responses to recombinant Asp f proteins were higher. Recombinant allergens stimulated cells to produce IFN-gamma more so than IL-4 or IL-17. Volunteers exhibited a diverse CD4+ and CD8+ T cell antigen recognition profile, with prominent CD4 T(H)1-responses to Asp f3 (a putative peroxismal membrane protein), Asp f9/16 (cell wall glucanase), Asp f11 (cyclophilin type peptidyl-prolyl isomerase) and Asp f22 (enolase). Strong IFN-gamma responses were reproduced in most subjects tested over 6 month intervals. Products secreted after conidial germination into hyphae are differentially recognized by protective T cells in healthy, non-atopic individuals. Defining the specificity of the human T cell repertoire, and identifying factors that govern early responses may allow for development of novel diagnostics and therapeutics for both invasive and allergic Aspergillus diseases.

  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. Specificity of antigens on UV radiation-induced antigenic tumor cell variants measured in vitro and in vivo

    International Nuclear Information System (INIS)

    Hostetler, L.W.; Romerdahl, C.A.; Kripke, M.L.

    1989-01-01

    The purpose of this study was to determine whether antigenic variants cross-react immunologically with the parental tumor and whether the UVR-associated antigen unique to UVR-induced tumors is also present on the variants. Antigenic (regressor) variants and nonimmunogenic (progressor) clones derived from UV-irradiated cultures of the C3H K1735 melanoma and SF19 spontaneous fibrosarcoma cell lines were used to address these questions. In an in vivo immunization and challenge assay, the antigenic variants did not induce cross-protection among themselves, but each induced immunity against the immunizing variant, the parent tumor cells, and nonimmunogenic clones derived from UV-irradiated parent cultures. Therefore, the variants can be used to induce in mice a protective immunity that prevents the growth of the parent tumor and nonimmunogenic clones, but not other antigenic variants. In contrast, immunization with cells of the parental tumor or the nonimmunogenic clones induced no protective immunity against challenge with any of the cell lines. Utilizing the K1735 melanoma-derived cell lines in vitro, T-helper (Th) cells isolated from tumor-immunized mice were tested for cross-reactivity by their ability to collaborate with trinitrophenyl-primed B-cells in the presence of trinitrophenyl-conjugated tumor cells. Also, the cross-reactivity of cytotoxic T-lymphocytes from tumor-immunized mice was assessed by a 4-h 51Cr-release assay. Antigenic variants induced cytotoxic T-lymphocytes and Th activity that was higher than that induced by the parent tumor and nonimmunogenic clones from the UVR-exposed parent tumor and cross-reacted with the parental tumor cells and nonimmunogenic clones, but not with other antigenic variants

  12. 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...

  13. Elevated Squamous Cell Carcinoma Antigen, Cytokeratin 19 Fragment, and Carcinoembryonic Antigen Levels in Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Jianzhong Chen

    2017-01-01

    Full Text Available Objective. We aimed to explore whether squamous cell carcinoma antigen (SCC, cytokeratin 19 fragment (Cyfra21-1, neuron-specific enolase (NSE, and carcinoembryonic antigen (CEA are elevated in diabetic nephropathy (DN and the association between urinary albumin-to-creatinine ratio (UACR and tumor markers in diabetic patients. Methods. Nondialysis patients with diabetes (n=261 and 90 healthy controls were enrolled. DN was defined as an UACR ≥ 30 mg/g in the absence of a urinary tract infection or other renal abnormalities. Results. Patients with DN had significantly higher serum SCC, Cyfra21-1, and CEA levels than those with normoalbuminuria and healthy controls. The rates of positive SCC, Cyfra21-1, and CEA significantly increased with increasing urinary albumin excretion (all P for trend < 0.001. In contrast, NSE was not affected by DN. SCC, Cyfra21-1, and CEA were significantly and positively correlated with UACR. In logistic regression, after multivariable adjustment, increased UACR was associated with increased odds ratio of elevated tumor marker levels (all P for trend < 0.05. Conclusions. Serum levels of SCC, Cyfra21-1, and CEA are markedly increased with increasing urinary albumin excretion, which affects the specificity for diagnosis for lung cancer. Appropriate interpretation of tumor markers in diabetic patients is mandatory to avoid unnecessary and even hazardous biopsies.

  14. Nanoscale artificial antigen presenting cells for cancer immunotherapy.

    Science.gov (United States)

    Rhodes, Kelly R; Green, Jordan J

    2018-03-07

    Exciting developments in cancer nanomedicine include the engineering of nanocarriers to deliver drugs locally to tumors, increasing efficacy and reducing off-target toxicity associated with chemotherapies. Despite nanocarrier advances, metastatic cancer remains challenging to treat due to barriers that prevent nanoparticles from gaining access to remote, dispersed, and poorly vascularized metastatic tumors. Instead of relying on nanoparticles to directly destroy every tumor cell, immunotherapeutic approaches target immune cells to train them to recognize and destroy tumor cells, which, due to the amplification and specificity of an adaptive immune response, may be a more effective approach to treating metastatic cancer. One novel technology for cancer immunotherapy is the artificial antigen presenting cell (aAPC), a micro- or nanoparticle-based system that mimics an antigen presenting cell by presenting important signal proteins to T cells to activate them against cancer. Signal 1 molecules target the T cell receptor and facilitate antigen recognition by T cells, signal 2 molecules provide costimulation essential for T cell activation, and signal 3 consists of secreted cues that further stimulate T cells. Classic microscale aAPCs present signal 1 and 2 molecules on their surface, and biodegradable polymeric aAPCs offer the additional capability of releasing signal 3 cytokines and costimulatory molecules that modulate the T cell response. Although particles of approximately 5-10 μm in diameter may be considered the optimal size of an aAPC for ex vivo cellular expansion, nanoscale aAPCs have demonstrated superior in vivo pharmacokinetic properties and are more suitable for systemic injection. As sufficient surface contact between T cells and aAPCs is essential for activation, nano-aAPCs with microscale contact surface areas have been created through engineering approaches such as shape manipulation and nanoparticle clustering. These design strategies have

  15. 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...

  16. Chimeric antigen receptor engineered stem cells: a novel HIV therapy.

    Science.gov (United States)

    Zhen, Anjie; Carrillo, Mayra A; Kitchen, Scott G

    2017-03-01

    Despite the success of combination antiretroviral therapy (cART) for suppressing HIV and improving patients' quality of life, HIV persists in cART-treated patients and remains an incurable disease. Financial burdens and health consequences of lifelong cART treatment call for novel HIV therapies that result in a permanent cure. Cellular immunity is central in controlling HIV replication. However, HIV adopts numerous strategies to evade immune surveillance. Engineered immunity via genetic manipulation could offer a functional cure by generating cells that have enhanced antiviral activity and are resistant to HIV infection. Recently, encouraging reports from several human clinical trials using an anti-CD19 chimeric antigen receptor (CAR) modified T-cell therapy for treating B-cell malignancies have provided valuable insights and generated remarkable enthusiasm in engineered T-cell therapy. In this review, we discuss the development of HIV-specific chimeric antigen receptors and the use of stem cell based therapies to generate lifelong anti-HIV immunity.

  17. T-cell dysfunction in HIV infection: anergy due to defective antigen-presenting cell function?

    NARCIS (Netherlands)

    Meyaard, L.; Schuitemaker, H.; Miedema, F.

    1993-01-01

    Before CD4+ T cells are depleted, T cells in asymptomatic HIV-infected individuals are functionally abnormal. These T cells are programmed for death, are non-responsive and fail to produce interleukin-2 after antigenic stimulation. Our view is that these different T-cell abnormalities are explained

  18. Defect internalization and tyrosine kinase activation in Aire deficient antigen presenting cells exposed to Candida albicans antigens.

    Science.gov (United States)

    Brännström, Johan; Hässler, Signe; Peltonen, Leena; Herrmann, Björn; Winqvist, Ola

    2006-12-01

    Patients with Autoimmune polyendocrine syndrome type I (APS I) present with multiple endocrine failures due to organ-specific autoimmune disease, thought to be T-cell-mediated. Paradoxically, APS I patients suffer from chronic mucocutaneous candidiasis. The mutated gene has been identified as the Autoimmune regulator (AIRE). Aire is expressed in medullary epithelial cells of the thymus and in antigen presenting cells in the periphery. T cells from Aire deficient mice and men displayed an enhanced proliferative response against Candida antigen in vitro, suggesting that Aire deficient T cells are competent in recognizing Candida albicans. In contrast, monocytes from APS I patients displayed a decreased and delayed internalization of zymosan. Furthermore, Candida antigen activated monocytes from APS I patients show decreased and altered phoshotyrosine kinase activation. In conclusion, Aire deficient APCs have a defect receptor mediated internalization of Candida which affects kinase activation, likely altering the innate Candida immune response.

  19. 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.

  20. Paired Expression Analysis of Tumor Cell Surface Antigens

    Directory of Open Access Journals (Sweden)

    Rimas J. Orentas

    2017-08-01

    Full Text Available Adoptive immunotherapy with antibody-based therapy or with T cells transduced to express chimeric antigen receptors (CARs is useful to the extent that the cell surface membrane protein being targeted is not expressed on normal tissues. The most successful CAR-based (anti-CD19 or antibody-based therapy (anti-CD20 in hematologic malignancies has the side effect of eliminating the normal B cell compartment. Targeting solid tumors may not provide a similar expendable marker. Beyond antibody to Her2/NEU and EGFR, very few antibody-based and no CAR-based therapies have seen broad clinical application for solid tumors. To expand the way in which the surfaceome of solid tumors can be analyzed, we created an algorithm that defines the pairwise relative overexpression of surface antigens. This enables the development of specific immunotherapies that require the expression of two discrete antigens on the surface of the tumor target. This dyad analysis was facilitated by employing the Hotelling’s T-squared test (Hotelling–Lawley multivariate analysis of variance for two independent variables in comparison to a third constant entity (i.e., gene expression levels in normal tissues. We also present a unique consensus scoring mechanism for identifying transcripts that encode cell surface proteins. The unique application of our bioinformatics processing pipeline and statistical tools allowed us to compare the expression of two membrane protein targets as a pair, and to propose a new strategy based on implementing immunotherapies that require both antigens to be expressed on the tumor cell surface to trigger therapeutic effector mechanisms. Specifically, we found that, for MYCN amplified neuroblastoma, pairwise expression of ACVR2B or anaplastic lymphoma kinase (ALK with GFRA3, GFRA2, Cadherin 24, or with one another provided the strongest hits. For MYCN, non-amplified stage 4 neuroblastoma, neurotrophic tyrosine kinase 1, or ALK paired with GFRA2, GFRA3, SSK

  1. Antigen-B Cell Receptor Complexes Associate with Intracellular major histocompatibility complex (MHC) Class II Molecules*

    Science.gov (United States)

    Barroso, Margarida; Tucker, Heidi; Drake, Lisa; Nichol, Kathleen; Drake, James R.

    2015-01-01

    Antigen processing and MHC class II-restricted antigen presentation by antigen-presenting cells such as dendritic cells and B cells allows the activation of naïve CD4+ T cells and cognate interactions between B cells and effector CD4+ T cells, respectively. B cells are unique among class II-restricted antigen-presenting cells in that they have a clonally restricted antigen-specific receptor, the B cell receptor (BCR), which allows the cell to recognize and respond to trace amounts of foreign antigen present in a sea of self-antigens. Moreover, engagement of peptide-class II complexes formed via BCR-mediated processing of cognate antigen has been shown to result in a unique pattern of B cell activation. Using a combined biochemical and imaging/FRET approach, we establish that internalized antigen-BCR complexes associate with intracellular class II molecules. We demonstrate that the M1-paired MHC class II conformer, shown previously to be critical for CD4 T cell activation, is incorporated selectively into these complexes and loaded selectively with peptide derived from BCR-internalized cognate antigen. These results demonstrate that, in B cells, internalized antigen-BCR complexes associate with intracellular MHC class II molecules, potentially defining a site of class II peptide acquisition, and reveal a selective role for the M1-paired class II conformer in the presentation of cognate antigen. These findings provide key insights into the molecular mechanisms used by B cells to control the source of peptides charged onto class II molecules, allowing the immune system to mount an antibody response focused on BCR-reactive cognate antigen. PMID:26400081

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

    Directory of Open Access Journals (Sweden)

    Todd M Brusko

    2010-07-01

    Full Text Available 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.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-based imaging.These results support the

  3. 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...

  4. Granulocytes: New Members of the Antigen-Presenting Cell Family

    Directory of Open Access Journals (Sweden)

    Ang Lin

    2017-12-01

    Full Text Available Granulocytes, the most abundant types of leukocytes, are the first line of defense against pathogen invasion. However, the plasticity and diversity of granulocytes have been increasingly revealed, especially with regard to their versatile functions in orchestrating adaptive immune responses. A substantial body of recent evidence demonstrates that granulocytes can acquire the function as antigen-presenting cells under pathological or inflammatory conditions. In addition, they can acquire surface expression of MHC class II and costimulatory molecules as well as T cell stimulatory behavior when cultured with selected cytokines. The classic view of granulocytes as terminally differentiated, short-lived phagocytes is therefore changing to phenotypically and functionally heterogeneous cells that are engaged in cross-talk with other leukocyte populations and provide an additional link between innate and adaptive immunity. In this brief review, we summarize the current knowledge on the antigen-presenting capacity of granulocyte subsets (neutrophils, eosinophils, and basophils. Underlying mechanisms, relevant physiological significance and potential controversies are also discussed.

  5. 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

  6. Interferon-gamma administration after abdominal surgery rescues antigen-specific helper T cell immune reactivity

    NARCIS (Netherlands)

    Rentenaar, R. J.; de Metz, J.; Bunders, M.; Wertheim-van Dillen, P. M.; Gouma, D. J.; Romijn, J. A.; Sauerwein, H. P.; ten Berge, I. J.; van Lier, R. A.

    2001-01-01

    Antigen-induced activation of T cells is determined by many factors. Among these factors are (i) the number of T-cell receptors (TCRs) triggered by TCR ligands on antigen-presenting cells (APCs), and (ii) the intrinsic cellular threshold for activation. T-cell receptor triggering is optimized by

  7. 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...... was time- and dose-dependent. A brief treatment solely of the accessory cells with the drug compromised their ability to stimulate primed T cells in a subsequent culture provided the accessory cells were treated with chloroquine before their exposure to the antigen. These results suggest that chloroquine...... acts on an early event in the antigen handling by accessory cells. Chloroquine is a well known inhibitor of lysosomal proteolysis, and it is likely that its effect on antigen presentation is caused by an inhibition of antigen degradation....

  8. Isolation and immunochemical characterization of carbohydrate antigens prepared from group A Streptococcus pyogenes.

    Science.gov (United States)

    Hamada, S; Okahashi, N; Yamamoto, T; Morisaki, I; Michalek, S M; McGhee, J R

    1983-11-01

    Group A carbohydrate antigens were prepared from isolated cell walls or whole cells of Streptococcus pyogenes strain Sv (group A, M type 3). Cell walls were lysate by the enzymatic action of M1 endo-N-acetylmuramidase. The cell wall lysate was concentrated and chromatographed on a Sephadex G-100 column. Two fractions reactive with group A antisera were obtained. These were composed of N-acetylglucosamine, rhamnose, and peptidoglycan components such as glutamic acid, lysine, alanine, N-acetylmuramic acid and N-acetylglucosamine. For comparison, hot TCA extract of the cell walls (TCAgA) or Rantz and Randall extract of the whole cells (RRgA) was purified chromatographically. The latter two also contained rhamnose and glucosamine, and were reactive with group A antisera. The molecular weights of M1gA antigens were larger than those of TCAgA and RRgA. Hapten inhibition study indicated that N-acetylglucosamine was the most potent inhibitor.

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

    DEFF Research Database (Denmark)

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

    2004-01-01

    B cells are centrally involved as antigen-presenting cells in certain autoimmune diseases. To establish whether autoantibodies form immune complexes (IC) with self-antigens in autoimmune thyroid disease (AITD) and promote B cell uptake of self-antigen, sera from patients with Hashimoto's thyroidi......B cells are centrally involved as antigen-presenting cells in certain autoimmune diseases. To establish whether autoantibodies form immune complexes (IC) with self-antigens in autoimmune thyroid disease (AITD) and promote B cell uptake of self-antigen, sera from patients with Hashimoto......'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 Tg by boiling reduced the proliferative responses. The data indicate that anti-Tg antibodies associated with AITD facilitate the formation of complement-activating Tg/anti-Tg complexes, binding of IC to B cells, and the subsequent proliferation of B and T cell subsets. This represents a novel...

  10. Flow cytometry and monoclonal antibodies identify normal liver cell populations antigenically related to oval cells.

    Science.gov (United States)

    Agelli, M; Halay, E D

    1995-01-01

    Oval cells, a non-parenchymal cell population induced to rapidly proliferate in animals treated with carcinogens, are thought to be related to the hypothesized liver stem cells. In normal liver there are poorly defined cells antigenically related to oval cells. These oval cell antigen positive (OCAP) cells present in normal animals are thought to include hepatocyte and bile duct cell precursors. To isolate them, we modified the existing protocols designed for oval cells and used it on normal neonatal rat livers. Using flow cytometry, the percentage of normal liver OCAP-cells varied with the monoclonal antibody (MoAb) to the different oval cell membrane markers used: 12% (MoAb 18.2), 23% (MoAb 270.38), 27% (MoAb 18.11), 31% (MoAb 18.13), and 37% (MoAb 374.3). Macrophages consisted 10% of the cells (MoAb MCA 275); hepatocytes were essentially absent ( < 1%, MoAb 236.4). Our results demonstrate that is possible to obtain significant numbers of normal cells antigenically related to oval cells and that using different MoAbs, different cell populations can be sorted for use in experimental studies testing liver progenitor cell hypothesis.

  11. Effects of oral intake of kimchi-derived Lactobacillus plantarum K8 lysates on skin moisturizing.

    Science.gov (United States)

    Kim, Hangeun; Kim, Hye Rim; Jeong, Bong Jun; Lee, Seung Su; Kim, Tae-Rahk; Jeong, Ji Hye; Lee, Miyeong; Lee, Sinai; Lee, Jong Suk; Chung, Dae Kyun

    2015-01-01

    Skin is the soft outer covering of vertebrates that provides protection from pathogenic infection, physical damage, or UV irradiation, and controls body temperature and water content. In this study, we examined the effects of oral intake of kimchi-derived Lactobacillus plantarum K8 lysates on skin moisturizing. In an in vitro study, we observed that the hyaluronic acid content increased in HaCaT cells treated with L. plantarum K8 lysates. Oral administration of L. plantarum K8 lysates effectively attenuated the horny layer formation and decreased epidermal thickening in DNCB-treated SKH-1 hairless mice skin. The damage to barrier function was reduced after 8 weeks of oral administration of L. plantarum K8 lysates as compared with that in the atopic dermatitis mice. For the test with volunteers, we manufactured experimental candy containing 2.1% L. plantarum K8 lysates, while control candy did not contain bacterial lysate. A significant increase in hydration in the experimental candy-administered group as compared with the control candy-administered group was observed on the face after 4 and 8 weeks, and on the forearm after 4 weeks. Decreases in horny layer thickness and TEWL value were observed on the face and forearm of the experimental group. Together, the in vitro cell line and in vivo mouse studies revealed that L. plantarum K8 lysates have a moisturizing effect. A clinical research study with healthy volunteers also showed an improvement in barrier repair and function when volunteers took L. plantarum K8 lysates-containing candy. Thus, our results suggest that L. plantarum K8 lysates may help to improve skin barrier function.

  12. Mast cells and dendritic cells form synapses that facilitate antigen transfer for T cell activation.

    Science.gov (United States)

    Carroll-Portillo, Amanda; Cannon, Judy L; te Riet, Joost; Holmes, Anna; Kawakami, Yuko; Kawakami, Toshiaki; Cambi, Alessandra; Lidke, Diane S

    2015-08-31

    Mast cells (MCs) produce soluble mediators such as histamine and prostaglandins that are known to influence dendritic cell (DC) function by stimulating maturation and antigen processing. Whether direct cell-cell interactions are important in modulating MC/DC function is unclear. In this paper, we show that direct contact between MCs and DCs occurs and plays an important role in modulating the immune response. Activation of MCs through FcεRI cross-linking triggers the formation of stable cell-cell interactions with immature DCs that are reminiscent of the immunological synapse. Direct cellular contact differentially regulates the secreted cytokine profile, indicating that MC modulation of DC populations is influenced by the nature of their interaction. Synapse formation requires integrin engagement and facilitates the transfer of internalized MC-specific antigen from MCs to DCs. The transferred material is ultimately processed and presented by DCs and can activate T cells. The physiological outcomes of the MC-DC synapse suggest a new role for intercellular crosstalk in defining the immune response. © 2015 Carroll-Portillo et al.

  13. Feeding dendritic cells with tumor antigens: self-service buffet or à la carte?

    OpenAIRE

    Melero, I. (Ignacio); Vile, R.G. (Richard G.); Colombo, M.P. (Mario P.)

    2000-01-01

    Adoptive transfer of autologous dendritic cells (DC) presenting tumor-associated antigens initiate and sustain an immune response which eradicate murine malignancies. Based on these observations, several clinical trials are in progress testing safety and efficacy with encouraging preliminary reports. In these approaches, ex vivo incubation of DC with a source of tumor antigens is required to load the relevant antigenic epitopes on the adequate antigen presenting molecules. Recent data show th...

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

    International Nuclear Information System (INIS)

    Diaz, Jason; Wang, Xin; Tsang, Sabrina H.; Jiao, Jing; You, Jianxin

    2014-01-01

    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

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

    Directory of Open Access Journals (Sweden)

    Jason Diaz

    2014-07-01

    Full Text Available 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.

  16. 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.

  17. Macropinocytosis in phagocytes: regulation of MHC class-II-restricted antigen presentation in dendritic cells.

    Science.gov (United States)

    Liu, Zhenzhen; Roche, Paul A

    2015-01-01

    Dendritic cells (DCs) are outstanding antigen presenting cells (APCs) due to their robust ability to internalize extracellular antigens using endocytic processes such as receptor-mediated endocytosis, phagocytosis, and macropinocytosis. Macropinocytosis mediates the non-specific uptake of soluble antigens and occurs in DCs constitutively. Macropinocytosis plays a key role in DC-mediated antigen presentation to T cells against pathogens and the efficiency of macropinocytosis in antigen capture is regulated during the process of DC maturation. Here, we review the methods to study macropinocytosis, describe our current knowledge of the regulatory mechanisms of antigen uptake via macropinocytosis and the intracellular trafficking route followed by macropinocytosed antigens, and discuss the significance of macropinocytosis for DC function.

  18. Macropinocytosis in Phagocytes: Regulation of MHC Class-II-Restricted Antigen Presentation in Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Zhenzhen eLiu

    2015-01-01

    Full Text Available AbstractDendritic cells (DCs are outstanding antigen presenting cells (APCs due to their robust ability to internalize extracellular antigens using endocytic processes such as receptor-mediated endocytosis, phagocytosis, and macropinocytosis. Macropinocytosis mediates the non-specific uptake of soluble antigens and occurs in DCs constitutively. Macropinocytosis plays a key role in DC-mediated antigen presentation to T cells against pathogens and the efficiency of macropinocytosis in antigen capture is regulated during the process of DC maturation. Here, we review the methods to study macropinocytosis, describe our current knowledge of the regulatory mechanisms of antigen uptake via macropinocytosis and the intracellular trafficking route followed by macropinocytosed antigens, and discuss the significance of macropinocytosis for DC function.

  19. 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...

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

    Directory of Open Access Journals (Sweden)

    Jared E. Knickelbein

    2009-11-01

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

  1. Stem cell antigen 1-positive mesenchymal cells are the origin of follicular cells during thyroid regeneration.

    Science.gov (United States)

    Okamoto, Minoru; Hayase, Suguru; Miyakoshi, Masaaki; Murata, Tsubasa; Kimura, Shioko

    2013-01-01

    Many tissues are thought to contain adult stem/progenitor cells that are responsible for repair of the tissue where they reside upon damage and/or carcinogenesis, conditions when cellular homeostasis becomes uncontrolled. While the presence of stem/progenitor cells of the thyroid has been suggested, how these cells contribute to thyroid regeneration remains unclear. Here we show the origin of thyroid follicular cells and the process of their maturation to become follicular cells during regeneration. By using β-galactosidase (β-gal) reporter mice in conjunction with partial thyroidectomy as a model for thyroid regeneration, and bromodeoxyuridine (BrdU) long label-retaining cell analysis, we demonstrated that stem cell antigen 1 (Sca1) and BrdU-positive, but β-gal and NKX2-1 negative cells were found in the non-follicular mesenchymal area 7 days after partial thyroidectomy. They temporarily co-expressed cytokeratin 14, and were observed in part of follicles by day 35 post-partial thyroidectomy. Sca1, BrdU, β-gal, and NKX2-1-positive cells were found 120 days post-partial thyroidectomy. These results suggested that Sca1 and BrdU positive cells may participate in the formation of new thyroid follicles after partial thyroidectomy. The process of thyroid follicular cell regeneration was recapitulated in ex vivo thyroid slice collagen gel culture studies. These studies will facilitate research on thyroid stem/progenitor cells and their roles in thyroid diseases, particularly thyroid carcinomas.

  2. 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

  3. 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.

  4. Molecular Validation of Chondrogenic Differentiation and Hypoxia Responsiveness of Platelet-Lysate Expanded Adipose Tissue–Derived Human Mesenchymal Stromal Cells

    NARCIS (Netherlands)

    Galeano-Garces, Catalina; Camilleri, Emily T.; Riester, Scott M.; Dudakovic, Amel; Larson, Dirk R.; Qu, Wenchun; Smith, Jay; Dietz, Allan B.; Im, Hee-Jeong; Krych, Aaron J.; Larson, A. Noelle; Karperien, Marcel; van Wijnen, Andre J.

    2017-01-01

    Objective: To determine the optimal environmental conditions for chondrogenic differentiation of human adipose tissue–derived mesenchymal stromal/stem cells (AMSCs). In this investigation we specifically investigate the role of oxygen tension and 3-dimensional (3D) culture systems. Design: Both

  5. A sub-population of circulating porcine gammadelta T cells can act as professional antigen presenting cells.

    Science.gov (United States)

    Takamatsu, H-H; Denyer, M S; Wileman, T E

    2002-09-10

    A sub-population of circulating porcine gammadelta T cells express cell surface antigens associated with antigen presenting cells (APCs), and are able to take up soluble antigen very effectively. Functional antigen presentation by gammadelta T cells to memory helper T cells was studied by inbred pig lymphocytes immunised with ovalbumin (OVA). After removing all conventional APCs from the peripheral blood of immunised pigs, the remaining lymphocytes still proliferated when stimulated with OVA. When gammadelta T cells were further depleted, OVA specific proliferation was abolished, but reconstitution with gammadelta T cells restored proliferation. The proliferation was blocked by monoclonal antibodies (mAb) against MHC class II or CD4, and by pre-treatment of gammadelta T cells with chloroquine. These results indicate that a sub-population of circulating porcine gammadelta T cells act as APCs and present antigen via MHC class II.

  6. Surface-Engineering of Red Blood Cells as Artificial Antigen Presenting Cells Promising for Cancer Immunotherapy.

    Science.gov (United States)

    Sun, Xiaoqi; Han, Xiao; Xu, Ligeng; Gao, Min; Xu, Jun; Yang, Rong; Liu, Zhuang

    2017-10-01

    The development of artificial antigen presenting cells (aAPCs) to mimic the functions of APCs such as dendritic cells (DCs) to stimulate T cells and induce antitumor immune responses has attracted substantial interests in cancer immunotherapy. In this work, a unique red blood cell (RBC)-based aAPC system is designed by engineering antigen peptide-loaded major histocompatibility complex-I and CD28 activation antibody on RBC surface, which are further tethered with interleukin-2 (IL2) as a proliferation and differentiation signal. Such RBC-based aAPC-IL2 (R-aAPC-IL2) can not only provide a flexible cell surface with appropriate biophysical parameters, but also mimic the cytokine paracrine delivery. Similar to the functions of matured DCs, the R-aAPC-IL2 cells can facilitate the proliferation of antigen-specific CD8+ T cells and increase the secretion of inflammatory cytokines. As a proof-of-concept, we treated splenocytes from C57 mice with R-aAPC-IL2 and discovered those splenocytes induced significant cancer-cell-specific lysis, implying that the R-aAPC-IL2 were able to re-educate T cells and induce adoptive immune response. This work thus presents a novel RBC-based aAPC system which can mimic the functions of antigen presenting DCs to activate T cells, promising for applications in adoptive T cell transfer or even in direct activation of circulating T cells for cancer immunotherapy. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Raised serum squamous cell carcinoma antigen levels in malignant transformation of mature cystic ovarian teratoma

    NARCIS (Netherlands)

    DeBruijn, HWA; Hollema, H; Willemse, PHB; TenHoor, KA; Boonstra, J.

    1996-01-01

    Mature cystic ovarian teratoma with malignant transformation to squamous cell carcinoma was diagnosed in four patients. Squamous cell carcinoma (SCC) antigen serum levels were elevated at diagnosis and during progression of the disease, but normal in complete remission. Elevated serum SCC antigen

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

    Indian Academy of Sciences (India)

    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 ...

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

    Indian Academy of Sciences (India)

    WINTEC

    Abstract. The interaction of pres1 region of hepatitis B virus B-cell epitope antigen with specific hepa- titis B neutralizing monoclonal antibody was examined by docking study. We modelled the 3D complex structure of B-cell epitope antigen residues CTTPAQGNSMFPSCCCTKPTDGNCY by homology model- ling and ...

  10. Identification of a Highly Antigenic Linear B Cell Epitope within Plasmodium vivax Apical Membrane Antigen 1 (AMA-1)

    Science.gov (United States)

    Bueno, Lilian Lacerda; Lobo, Francisco Pereira; Morais, Cristiane Guimarães; Mourão, Luíza Carvalho; de Ávila, Ricardo Andrez Machado; Soares, Irene Silva; Fontes, Cor Jesus; Lacerda, Marcus Vinícius; Olórtegui, Carlos Chavez; Bartholomeu, Daniella Castanheira; Fujiwara, Ricardo Toshio; Braga, Érika Martins

    2011-01-01

    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. PMID:21713006

  11. 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.

  12. Adoptive T Cell Therapies: A Comparison of T Cell Receptors and Chimeric Antigen Receptors

    Science.gov (United States)

    Harris, Daniel T.; Kranz, David M.

    2016-01-01

    The tumor-killing properties of T cells provide tremendous opportunities to treat cancer. Adoptive T cell therapies have begun to harness this potential by endowing a functionally diverse repertoire of T cells with genetically modified, tumor-specific recognition receptors. Normally, this antigen recognition function is mediated by an αβ T cell receptor (TCR), but the dominant therapeutic forms currently in development are synthetic constructs called chimeric antigen receptors (CARs). While CAR-based adoptive cell therapies are already showing great promise, their basic mechanistic properties have been studied in less detail compared with those of αβ TCRs. In this review, we compare and contrast various features of TCRs versus CARs, with a goal of highlighting issues that need to be addressed to fully exploit the therapeutic potential of both. PMID:26705086

  13. 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...

  14. Germ tube-specific antigens of Candida albicans cell walls

    International Nuclear Information System (INIS)

    Sundstrom, P.R.

    1986-01-01

    Studies were performed to characterize the surface differences between blastospores and germ tubes of the pathogenic, dimorphic yeast, Candida albicans, and to identify components of yeast cells responsible for these differences. Investigation of surfaces differences of the two growth forms was facilitated by the production of rabbit antiserum prepared against Formalin-treated yeast possessing germ tubes. To prepare antiserum specific for germ tubes, this serum was adsorbed with stationary phase blastospores. Whereas the unadsorbed antiserum reacted with both blastospore and germ tube forms by immunofluorescence and Enzyme-Linked Immunosorbent Assay, the adsorbed antiserum did not react with blastospores but detected germ tube-specific antigens in hyphal forms. The differences between blastospores and germ tubes of Candida albicans, were further studied by comparing enzymatic digests of cell walls of both growth forms in radiolabeled organisms. Organisms were labeled either on the surface with 125 I, or metabolically with [ 35 S] methionine or [ 3 H] mannose. Three-surface-located components (as shown by antibody adsorption and elution experiments) were precipitated from Zymolase digests. All three components were mannoproteins as shown by their ability to bind Concanavalin A, and to be labeled in protein labeling procedures, and two of these (200,000 and 155,000 molecular weight) were germ tube specific, as shown by their ability to be precipitated by germ tube-specific antiserum. Monoclonal antibodies were prepared to C. albicans, using blastospores bearing germ tubes as immunogen

  15. Regulation of the Cell Biology of Antigen Cross-Presentation.

    Science.gov (United States)

    Blander, J Magarian

    2018-02-28

    Antigen cross-presentation is an adaptation of the cellular process of loading MHC-I molecules with endogenous peptides during their biosynthesis within the endoplasmic reticulum. Cross-presented peptides derive from internalized proteins, microbial pathogens, and transformed or dying cells. The physical separation of internalized cargo from the endoplasmic reticulum, where the machinery for assembling peptide-MHC-I complexes resides, poses a challenge. To solve this problem, deliberate rewiring of organelle communication within cells is necessary to prepare for cross-presentation, and different endocytic receptors and vesicular traffic patterns customize the emergent cross-presentation compartment to the nature of the peptide source. Three distinct pathways of vesicular traffic converge to form the ideal cross-presentation compartment, each regulated differently to supply a unique component that enables cross-presentation of a diverse repertoire of peptides. Delivery of centerpiece MHC-I molecules is the critical step regulated by microbe-sensitive Toll-like receptors. Defining the subcellular sources of MHC-I and sites of peptide loading during cross-presentation remain key challenges. Expected final online publication date for the Annual Review of Immunology Volume 36 is April 26, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  16. Viral antigen production in cell cultures on microcarriers Bovine parainfluenza 3 virus and MDBK cells.

    Science.gov (United States)

    Conceição, M M; Tonso, A; Freitas, C B; Pereira, C A

    2007-11-07

    Viral antigens can be obtained from infected mammalian cells cultivated on microcarriers. We have worked out parameters for the production of bovine parainfluenza 3 (PI-3) virus by Mandin-Darby Bovine Kidney (MDBK) cells cultivated on Cytodex 1 microcarriers (MCs) in spinners flasks and bioreactor using fetal bovine serum (FBS) supplemented Eagle minimal essential medium (Eagle-MEM). Medium renewal during the cell culture was shown to be crucial for optimal MCs loading (>90% MCs with confluent cell monolayers) and cell growth (2.5 x 10(6)cells/mL and a micro(x) (h(-1)) 0.05). Since cell cultures performed with lower amount of MCs (1g/L), showed good performances in terms of cell loading, we designed batch experiments with a lower concentration of MCs in view of optimizing the cell growth and virus production. Studies of cell growth with lower concentrations of MCs (0.85 g/L) showed that an increase in the initial cell seeding (from 7 to 40 cells/MC) led to a different kinetic of initial cell growth but to comparable final cell concentrations ((8-10)x10(5)cells/mL at 120 h) and cell loading (210-270 cells/MC). Upon infection with PI-3 virus, cultures showed a decrease in cell growth and MC loading directly related to the multiplicity of infection (moi) used for virus infection. Infected cultures showed also a higher consumption of glucose and production of lactate. The PI-3 virus and PI-3 antigen production among the cultures was not significantly different and attained values ranging from, respectively, 7-9 log(10) TCID(50)/mL and 1.5-2.2 OD. The kinetics of PI-3 virus production showed a sharp increase during the first 24h and those of PI-3 antigen increased after 24h. The differential kinetics of PI-3 virus and PI-3 antigen can be explained by the virus sensitivity to temperature. In view of establishing a protocol of virus production and based on the previous experiments, MDBK cell cultures performed under medium perfusion in a bioreactor of 1.2L were infected

  17. Licensing of γδT cells for professional antigen presentation

    Science.gov (United States)

    Anderson, John; Gustafsson, Kenth; Himoudi, Nourredine; Yan, Mengyong; Heuijerjans, Jennifer

    2012-01-01

    Following activation, γδ T cells display many properties of lymphocytes from the innate immune system, yet how they mediate antigen presentation remains an open conundrum. In humans, circulating γδ T cells that express the Vγ9Vδ2 T-cell receptor become reversibly licensed for professional antigen presentation only upon interaction with a target cell opsonized with IgGs. PMID:23264926

  18. Lymphoid cell blastogenesis as an in vitro indicator of cellular immunity to Legionella pneumophila antigens.

    OpenAIRE

    Friedman, F; Widen, R; Klein, T; Friedman, H

    1984-01-01

    The lymphocyte blastogenic transformation assay was adapted to study responsiveness of lymphoid cells from animals and humans to Legionella pneumophila antigens in vitro. Spleen cells from guinea pigs after active immunization with Legionella vaccine, but not from normal animals, responded by blast cell transformation when stimulated in vitro with killed Legionella whole-cell vaccine, sonic extracts thereof, or a purified somatic antigen. The response was dose dependent. Similar lymphocyte bl...

  19. Cancer antigens are expressed in a carcinogen-transformed Bloom syndrome B-lymphoblastoid cell line

    International Nuclear Information System (INIS)

    Shiraishi, Yukimasa; Soma, Hiroaki

    1988-01-01

    The authors have cloned malignant cells carrying specific antigens associated with ovarian cancer (OVC) and malignant lymphoma (ML) from BS-SHI-4M cells, a line derived from a 1-methyl-3-nitro-1-nitrosoguanidine-treated B-lymphoblastoid cell line isolated from a patient with Bloom syndrome. Since BS-SHI-4M cells react with sera from various individual cancer patients at relatively low frequencies (2-9%), as detected by an indirect immunofluorescence technique, cell clones that specifically react with sera from patients with OVC and ML were separated by the panning method in which polystyrene dishes were coated with sera from OVC and ML patients and cells with the corresponding antigens bound to the dishes. Subsequent cloning by limiting dilution provided cell clones highly enriched for OVC- and ML-associated antigens. Karyotype analyses revealed that cell clones with OVC and ML antigens had common marker chromosomes. Interestingly, in cell clones with a strong OVC antigen response, the distal part of the Y chromosome (Yq11) was missing in 100% of the cells. Therefore the cell line BS-SHI-4M appears to be a reservoir of cell clones each of which carries a specific tumor antigen and thus provides a potential tool for rapid serological diagnosis of cancer

  20. Stabilization of Transfected Cells Expressing Low-Incidence Blood Group Antigens: Novel Methods Facilitating Their Use as Reagent-Cells.

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    Cecilia González

    Full Text Available The identification of erythrocyte antibodies in the serum of patients rely on panels of human red blood cells (RBCs, which coexpress many antigens and are not easily available for low-incidence blood group phenotypes. These problems have been addressed by generating cell lines expressing unique blood group antigens, which may be used as an alternative to human RBCs. However, the use of cell lines implies several drawbacks, like the requirement of cell culture facilities and the high cost of cryopreservation. The application of cell stabilization methods could facilitate their use as reagent cells in clinical laboratories.We generated stably-transfected cells expressing low-incidence blood group antigens (Dia and Lua. High-expresser clones were used to assess the effect of TransFix® treatment and lyophilization as cell preservation methods. Cells were kept at 4°C and cell morphology, membrane permeability and antigenic properties were evaluated at several time-points after treatment.TransFix® addition to cell suspensions allows cell stabilization and proper antigen detection for at least 120 days, despite an increase in membrane permeability and a reduction in antigen expression levels. Lyophilized cells showed minor morphological changes and antigen expression levels were rather conserved at days 1, 15 and 120, indicating a high stability of the freeze-dried product. These stabilized cells have been proved to react specifically with human sera containing alloantibodies.Both stabilization methods allow long-term preservation of the transfected cells antigenic properties and may facilitate their distribution and use as reagent-cells expressing low-incidence antigens, overcoming the limited availability of such rare RBCs.

  1. Potent antigen-specific immune response induced by infusion of spleen cells coupled with succinimidyl-4-(N-maleimidomethyl cyclohexane)-1-carboxylate (SMCC) conjugated antigens.

    Science.gov (United States)

    Guo, Yixian; Werbel, Tyler; Wan, Suigui; Wu, Haitao; Li, Yaohua; Clare-Salzler, Michael; Xia, Chang-Qing

    2016-02-01

    In the present study, we report our recently developed new approach to inducing antigen-specific immune response. We use two nucleophilic substitution "click" chemistry processes to successfully couple protein antigens or peptides to mouse spleen cells or T cells by a heterobifunctional crosslinker, succinimidyl-4-(N-maleimidomethyl cyclohexane)-1-carboxylate (SMCC) or sulfo-SMCC. SMCC and its water-soluble analog sulfo-SMCC contain N-hydroxysuccinimide (NHS) ester and maleimide groups, which allow stable covalent conjugation of amine- and sulfhydryl-containing molecules in trans. Protein coupling to cells relies on the free sulfhydryls (thiols) on cell surfaces and the free amines on protein antigens. Although the amount of protein coupled to cells is limited due to the limited number of cell surface thiols, the injection of spleen cells coupled with antigenic proteins, such as keyhole limpet hemocyanin (KLH) or ovalbumin (OVA), induces a potent antigen-specific immune response in vivo, which is even stronger than that induced by the injection of a large dose of protein plus adjuvants. In addition, short peptides coupled to purified splenic T cells also potently elicit peptide-specific T cell proliferation in vivo after injection. Further studies show that antigen-coupled spleen cell treatment leads to augmented IFN-γ-producing T cells. Our study provides a unique antigen delivery method that efficiently distributes antigen to the entire immune system, subsequently eliciting a potent antigen-specific immune response with enhanced IFN-γ production. The findings in the present study suggest that this antigen-cell coupling strategy could be employed in immunotherapy for cancers, infectious diseases as well as immune-mediated disorders. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Chimeric Antigen Receptor-Engineered T Cells in Tumor Immunotherapy: From Bench to Beside

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    Peng WANG

    2017-06-01

    Full Text Available Chimeric antigen receptor-engineered T cells (CAR-T cells, a classification of cultured T cells after modification of gene engineering technology, can recognize specific tumor antigens in a major histocompatibility complex (MHC-independent manner, consequently leading to the activation of antitumor function. The recent studies have confirmed that a variety of tumor-associated antigens (TAAs can act as target antigens for CAR-T cells. Nowadays, CAR T-cell therapy, one of the most potential tumor immunotherapies, has made great breakthroughs in hematological malignancies and promising outcomes in solid tumors. In this article, the biological characteristics and antitumor mechanism of CAR-T cells, and their application in tumor treatment were mainly reviewed.

  3. Effective antigen cross-presentation by prostate cancer patients' dendritic cells: implications for prostate cancer immunotherapy.

    Science.gov (United States)

    Orange, D E; Jegathesan, M; Blachère, N E; Frank, M O; Scher, H I; Albert, M L; Darnell, R B

    2004-01-01

    Despite the potency with which dendritic cells (DCs) are able to utilize the exogenous MHC I antigen cross-presentation pathway to cross-present antigen for the activation of killer T cells in model systems, concern about defects in immune function in cancer patients has led to uncertainty regarding whether immune cells derived from patients can effectively be used to generate tumor vaccines. We have undertaken a careful analysis of the potency of using DCs obtained from prostate cancer patients to cross-present antigen derived from human prostate tumor cells for the activation of antigen-specific T cells. Such DCs can be matured ex vivo into functionally active cells and are capable of cross-presenting influenza antigen derived from internalized apoptotic prostate tumor cells. Importantly, we demonstrate effective stimulation of both CD4+ and CD8+ T cells, as evident by production of IFN-gamma, and the ability of CD8+ T cells to differentiate into effector CTLs. These results, defining conditions in which prostate cancer patient DCs can efficiently utilize the cross-presentation pathway and in which apoptotic tumor can serve as a source of antigen for DCs to activate T cells, demonstrate that this system warrants clinical study as a potential immunotherapy.

  4. Spreading the load: Antigen transfer between migratory and lymph node-resident dendritic cells promotes T-cell priming.

    Science.gov (United States)

    Mueller, Scott N

    2017-10-01

    Dendritic cells (DC) are specialized in the processing and presentation of antigen for the activation of lymphocytes. Multiple subsets of DCs exist with distinct functions and roles in the initiation of immune responses. DCs found within tissues acquire antigens or become infected by pathogens and migrate to local draining lymph nodes (LN) where they can directly stimulate T cells. These migratory DCs can also transfer antigens to LN-resident DCs and may indirectly enhance T cell priming. In this issue of the European Journal of Immunology, Gurevich et al. [Eur. J. Immunol. 2017. 47: 1802-1818] elegantly demonstrate the influence of the transfer of antigen from migratory DCs to resident DCs on the dynamics of CD8 T-cell priming in mice. Using both in vitro imaging to visualise antigen dissemination and intravital 2-photon microscopy to track T cell clustering with migratory and resident DCs, antigen-donor DC were found to efficiently distribute antigen to recipient DC. This process, which involved LFA-1, enhanced the recruitment of CD8 + T cells into the response and rescued priming when DCs were impaired in presentation capacity. Together, these findings shed light on the dynamics of the transfer of antigens between DCs in vivo for the efficient priming of cytotoxic T cell responses. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Surface Antigen Profiling of Helicobacter pylori-Infected and -Uninfected Gastric Cancer Cells Using Antibody Microarray.

    Science.gov (United States)

    Sukri, Asif; Hanafiah, Alfizah; Kosai, Nik Ritza; Mohamed Taher, Mustafa; Mohamed Rose, Isa

    2016-10-01

    Comprehensive immunophenotyping cluster of differentiation (CD) antigens in gastric adenocarcinoma, specifically between Helicobacter pylori-infected and -uninfected gastric cancer patients by using DotScan(™) antibody microarray has not been conducted. Current immunophenotyping techniques include flow cytometry and immunohistochemistry are limited to the use of few antibodies for parallel examination. We used DotScan(™) antibody microarray consisting 144 CD antibodies to determine the distribution of CD antigens in gastric adenocarcinoma cells and to elucidate the effect of H. pylori infection toward CD antigen expression in gastric cancer. Mixed leukocytes population derived from gastric adenocarcinoma patients were immunophenotyped using DotScan(™) antibody microarray. AGS cells were infected with H. pylori strains and cells were captured on DotScan(™) slides. Cluster of differentiation antigens involved in perpetuating the tolerance of immune cells to tumor cells was upregulated in gastric adenocarcinoma cells compared to normal cells. CD279 which is essential in T cells apoptosis was found to be upregulated in normal cells. Remarkably, H. pylori-infected gastric cancer patients exhibited upregulated expression of CD27 that important in maintenance of T cells. Infection of cagA+ H. pylori with AGS cells increased CD antigens expression which involved in cancer stem cell while cagA- H. pylori polarized AGS cells to express immune-regulatory CD antigens. Increased CD antigens expression in AGS cells infected with cagA+ H. pylori were also detected in H. pylori-infected gastric cancer patients. This study suggests the tolerance of immune system toward tumor cells in gastric cancer and distinct mechanisms of immune responses exploited by different H. pylori strains. © 2016 John Wiley & Sons Ltd.

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

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    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.

  7. 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.

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

    International Nuclear Information System (INIS)

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

    1985-01-01

    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 [ 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 [ 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

  9. Despite disorganized synapse structure, Th2 cells maintain directional delivery of CD40L to antigen-presenting B cells.

    Directory of Open Access Journals (Sweden)

    Jennifer L Gardell

    Full Text Available Upon recognition of peptide displayed on MHC molecules, Th1 and Th2 cells form distinct immunological synapse structures. Th1 cells have a bull's eye synapse structure with TCR/ MHC-peptide interactions occurring central to a ring of adhesion molecules, while Th2 cells have a multifocal synapse with small clusters of TCR/MHC interactions throughout the area of T cell/antigen-presenting cell interaction. In this study, we investigated whether this structural difference in the immunological synapse affects delivery of T cell help. The immunological synapse is thought to ensure antigen-specific delivery of cytolytic granules and killing of target cells by NK cells and cytolytic T cells. In helper T cells, it has been proposed that the immunological synapse may direct delivery of other effector molecules including cytokines. CD40 ligand (CD40L is a membrane-bound cytokine essential for antigen-specific T cell help for B cells in the antibody response. We incubated Th1 and Th2 cells overnight with a mixture of antigen-presenting and bystander B cells, and the delivery of CD40L to B cells and subsequent B cell responses were compared. Despite distinct immunological synapse structures, Th1 and Th2 cell do not differ in their ability to deliver CD40L and T cell help in an antigen-specific fashion, or in their susceptibility to inhibition of help by a blocking anti-CD40L antibody.

  10. Despite disorganized synapse structure, Th2 cells maintain directional delivery of CD40L to antigen-presenting B cells.

    Science.gov (United States)

    Gardell, Jennifer L; Parker, David C

    2017-01-01

    Upon recognition of peptide displayed on MHC molecules, Th1 and Th2 cells form distinct immunological synapse structures. Th1 cells have a bull's eye synapse structure with TCR/ MHC-peptide interactions occurring central to a ring of adhesion molecules, while Th2 cells have a multifocal synapse with small clusters of TCR/MHC interactions throughout the area of T cell/antigen-presenting cell interaction. In this study, we investigated whether this structural difference in the immunological synapse affects delivery of T cell help. The immunological synapse is thought to ensure antigen-specific delivery of cytolytic granules and killing of target cells by NK cells and cytolytic T cells. In helper T cells, it has been proposed that the immunological synapse may direct delivery of other effector molecules including cytokines. CD40 ligand (CD40L) is a membrane-bound cytokine essential for antigen-specific T cell help for B cells in the antibody response. We incubated Th1 and Th2 cells overnight with a mixture of antigen-presenting and bystander B cells, and the delivery of CD40L to B cells and subsequent B cell responses were compared. Despite distinct immunological synapse structures, Th1 and Th2 cell do not differ in their ability to deliver CD40L and T cell help in an antigen-specific fashion, or in their susceptibility to inhibition of help by a blocking anti-CD40L antibody.

  11. Effects of radiation on the expression of antigens on the membranes of human adenocarcinoma cells

    International Nuclear Information System (INIS)

    Hareyama, Masato; Imai, Kozo; Oouchi, Atsushi; Shidou, Mitsuo; Takahashi, Hiroki; Koshiba, Hirohumi; Yachi, Akira; Morita, Kazuo

    1992-01-01

    We have investigated the effects of irradiation on the membranes of tumor cells. X-ray irradiation caused remarkable increases in the expression of tumor-associated antigens (YH206, CEA) and c-erbB-2 protein by flow cytometry, whereas IFN had no obvious effect on the expression of tumor-associated antigens and c-erbB-2 protein. On the other hand, the expression of MHC Class I and ICAM-1 antigen on the membrane by flow cytometry was enhanced by both irradiation and IFN. In addition, the irradiated cells, when analyzed using a CEA specific probe, showed remarkable increases in the CEA mRNA compared to IFN-treated cells. It is possible that enhancement of the expression of tumor-associated antigens and c-erbB-2 protein, together with the enhancement of that of MHC-Class I and ICAM-1, would help cytotoxic killer cells recognize the tumor cells. (author)

  12. MHC class I-presented tumor antigen appraisable for T-cell responses against ovarian cancer

    Directory of Open Access Journals (Sweden)

    Jing Yao Wang

    2015-08-01

    Full Text Available The purpose of this study is to assess whether MHC class I-presented tumor antigen is appraisable for T-cell responses against ovarian cancer. In ovarian cancer cell, human leukocyte antigen A2 (HLA-A2 associated with peptides was used to promote the activation of naive T cells so as to activate antigen-specific T cells. 7 or 4 patients were observed grade 1 or 2 injection site reactions, respectively. 5, 2 or 1 patients were observed grade 1, 2 or 3 pain reactions, respectively. 4 or 1 patients were observed grade 1 or 2 induration reactions. Total number mean value of patients experiencing response to the particular peptide was 7.73, and total number mean value of peptides to which the patients responded was 7.45. MHC class I-presented tumor antigen is appraisable for T-cell responses against ovarian cancer in China.

  13. Langerhans Cells Prevent Autoimmunity via Expansion of Keratinocyte Antigen-Specific Regulatory T Cells

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    Daniela Y. Kitashima

    2018-01-01

    Full Text Available Langerhans cells (LCs are antigen-presenting cells in the epidermis whose roles in antigen-specific immune regulation remain incompletely understood. Desmoglein 3 (Dsg3 is a keratinocyte cell-cell adhesion molecule critical for epidermal integrity and an autoantigen in the autoimmune blistering disease pemphigus. Although antibody-mediated disease mechanisms in pemphigus are extensively characterized, the T cell aspect of this autoimmune disease still remains poorly understood. Herein, we utilized a mouse model of CD4+ T cell-mediated autoimmunity against Dsg3 to show that acquisition of Dsg3 and subsequent presentation to T cells by LCs depended on the C-type lectin langerin. The lack of LCs led to enhanced autoimmunity with impaired Dsg3-specific regulatory T cell expansion. LCs expressed the IL-2 receptor complex and the disruption of IL-2 signaling in LCs attenuated LC-mediated regulatory T cell expansion in vitro, demonstrating that direct IL-2 signaling shapes LC function. These data establish that LCs mediate peripheral tolerance against an epidermal autoantigen and point to langerin and IL-2 signaling pathways as attractive targets for achieving tolerogenic responses particularly in autoimmune blistering diseases such as pemphigus.

  14. CD8(+)NKT-like cells regulate the immune response by killing antigen-bearing DCs.

    Science.gov (United States)

    Wang, Chao; Liu, Xi; Li, Zhengyuan; Chai, Yijie; Jiang, Yunfeng; Wang, Qian; Ji, Yewei; Zhu, Zhongli; Wan, Ying; Yuan, Zhenglong; Chang, Zhijie; Zhang, Minghui

    2015-09-15

    CD1d-dependent NKT cells have been extensively studied; however, the function of CD8(+)NKT-like cells, which are CD1d-independent T cells with NK markers, remains unknown. Here, we report that CD1d-independent CD8(+)NKT-like cells, which express both T cell markers (TCRβ and CD3) and NK cell receptors (NK1.1, CD49b and NKG2D), are activated and significantly expanded in mice immunized with GFP-expressing dendritic cells. Distinct from CD1d-dependent NKT cells, CD8(+)NKT-like cells possess a diverse repertoire of TCRs and secrete high levels of IFN-gamma but not IL-4. CD8(+)NKT-like cell development is normal in CD1d(-/-) mice, which suggests that CD8(+)NKT-like cells undergo a unique development pathway that differs from iNKT cells. Further functional analyses show that CD8(+)NKT-like cells suppress T-cell responses through elimination of dendritic cells in an antigen-specific manner. Adoptive transfer of antigen-specific CD8(+)NKT-like cells into RIP-OVA mice prevented subsequent development of diabetes in the animals induced by activated OT-I CD8 T cells. Our study suggests that CD8(+)NKT-like cells can function as antigen-specific suppressive cells to regulate the immune response through killing antigen-bearing DCs. Antigen-specific down regulation may provide an active and precise method for constraining an excessive immune response and avoiding bypass suppression of necessary immune responses to other antigens.

  15. CD8+NKT-like cells regulate the immune response by killing antigen-bearing DCs

    Science.gov (United States)

    Wang, Chao; Liu, Xi; Li, Zhengyuan; Chai, Yijie; Jiang, Yunfeng; Wang, Qian; Ji, Yewei; Zhu, Zhongli; Wan, Ying; Yuan, Zhenglong; Chang, Zhijie; Zhang, Minghui

    2015-01-01

    CD1d-dependent NKT cells have been extensively studied; however, the function of CD8+NKT-like cells, which are CD1d-independent T cells with NK markers, remains unknown. Here, we report that CD1d-independent CD8+NKT-like cells, which express both T cell markers (TCRβ and CD3) and NK cell receptors (NK1.1, CD49b and NKG2D), are activated and significantly expanded in mice immunized with GFP-expressing dendritic cells. Distinct from CD1d-dependent NKT cells, CD8+NKT-like cells possess a diverse repertoire of TCRs and secrete high levels of IFN-gamma but not IL-4. CD8+NKT-like cell development is normal in CD1d−/− mice, which suggests that CD8+NKT-like cells undergo a unique development pathway that differs from iNKT cells. Further functional analyses show that CD8+NKT-like cells suppress T-cell responses through elimination of dendritic cells in an antigen-specific manner. Adoptive transfer of antigen-specific CD8+NKT-like cells into RIP-OVA mice prevented subsequent development of diabetes in the animals induced by activated OT-I CD8 T cells. Our study suggests that CD8+NKT-like cells can function as antigen-specific suppressive cells to regulate the immune response through killing antigen-bearing DCs. Antigen-specific down regulation may provide an active and precise method for constraining an excessive immune response and avoiding bypass suppression of necessary immune responses to other antigens. PMID:26369936

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

    Directory of Open Access Journals (Sweden)

    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

  17. Endocytosis and recycling of immune complexes by follicular dendritic cells enhances B cell antigen binding and activation

    Science.gov (United States)

    Heesters, Balthasar A.; Chatterjee, Priyadarshini; Kim, Young-A; Gonzalez, Santiago F.; Kuligowski, Michael P.; Kirchhausen, Tomas; Carroll, Michael C.

    2013-01-01

    Summary Stromal derived follicular dendritic cells (FDCs) are a major reservoir for antigen that is essential for formation of germinal centers, the site where memory and effector B cells differentiate. A long-standing question is how FDCs retain antigen in its native form for extended periods and how they display it to specific B cells. Here we found that FDC acquired complement-coated immune complexes (IC) from non-cognate B cells via complement receptors 1 and 2 (CD35 and CD21 respectively) and rapidly internalized them by an actin-dependent pathway. IC were retained intact within a non-degradative cycling compartment and were displayed periodically on the cell surface where they were accessible to antigen-specific B cells. This would explain how antigens are protected from damage and retained over long periods of time, while remaining accessible for B cells. PMID:23770227

  18. Cancer Patient T Cells Genetically Targeted to Prostate-Specific Membrane Antigen Specifically Lyse Prostate Cancer Cells and Release Cytokines in Response to Prostate-Specific Membrane Antigen

    Directory of Open Access Journals (Sweden)

    Michael C. Gong

    1999-06-01

    Full Text Available The expression of immunoglobulin-based artificial receptors in normal T lymphocytes provides a means to target lymphocytes to cell surface antigens independently of major histocompatibility complex restriction. Such artificial receptors have been previously shown to confer antigen-specific tumoricidal properties in murine T cells. We constructed a novel ζ chain fusion receptor specific for prostate-specific membrane antigen (PSMA termed Pz-1. PSMA is a cell-surface glycoprotein expressed on prostate cancer cells and the neovascular endothelium of multiple carcinomas. We show that primary T cells harvested from five of five patients with different stages of prostate cancer and transduced with the Pz-1 receptor readily lyse prostate cancer cells. Having established a culture system using fibroblasts that express PSMA, we next show that T cells expressing the Pz-1 receptor release cytokines in response to cell-bound PSMA. Furthermore, we show that the cytokine release is greatly augmented by B7.1-mediated costimulation. Thus, our findings support the feasibility of adoptive cell therapy by using genetically engineered T cells in prostate cancer patients and suggest that both CD4+ and CD8+ T lymphocyte functions can be synergistically targeted against tumor cells.

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

    Science.gov (United States)

    Kitchen, Scott G; Bennett, Michael; Galić, Zoran; Kim, Joanne; Xu, Qing; Young, Alan; Lieberman, Alexis; Joseph, Aviva; Goldstein, Harris; Ng, Hwee; Yang, Otto; Zack, Jerome A

    2009-12-07

    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.

  20. 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.

  1. Antigen storage compartments in mature dendritic cells facilitate prolonged cytotoxic T lymphocyte cross-priming capacity.

    Science.gov (United States)

    van Montfoort, Nadine; Camps, Marcel G; Khan, Selina; Filippov, Dmitri V; Weterings, Jimmy J; Griffith, Janice M; Geuze, Hans J; van Hall, Thorbald; Verbeek, J Sjef; Melief, Cornelis J; Ossendorp, Ferry

    2009-04-21

    Dendritic cells (DCs) are crucial for priming of naive CD8(+) T lymphocytes to exogenous antigens, so-called "cross-priming." We report that exogenous protein antigen can be conserved for several days in mature DCs, coinciding with strong cytotoxic T lymphocyte cross-priming potency in vivo. After MHC class I peptide elution, protein antigen-derived peptide presentation is efficiently restored, indicating the presence of an intracellular antigen depot. We characterized this depot as a lysosome-like organelle, distinct from MHC class II compartments and recently described early endosomal compartments that allow acute antigen presentation in MHC class I. The storage compartments we report here facilitate continuous supply of MHC class I ligands. This mechanism ensures sustained cross-presentation by DCs, despite the short-lived expression of MHC class I-peptide complexes at the cell surface.

  2. Cellular Cancer Vaccines: an Update on the Development of Vaccines Generated from Cell Surface Antigens

    Directory of Open Access Journals (Sweden)

    Petr G. Lokhov, Elena E. Balashova

    2010-01-01

    Full Text Available A recent advance in anti-cancer therapies has been the use of cancer cells to develop vaccines. However, immunization with cancer cell-based vaccines has not resulted in significant long-term therapeutic benefits. A possible reason for this is that while cancer cells provide surface antigens that are targets for a desired immune response, they also contain a high abundance of housekeeping proteins, carbohydrates, nucleic acids, lipids, and other intracellular contents that are ubiquitous in all mammalian cells. These ubiquitous molecules are not the intended targets of this therapy approach, and thus, the immune response generated is not sufficient to eliminate the cancer cells present. In this review, a discussion of the cell surface of cancer cells is presented in relation to the goals of improving antigen composition of cancer cell-based vaccines. Strategies to enrich vaccines for cancer-specific antigens are also discussed.

  3. JC virus T-antigen regulates glucose metabolic pathways in brain tumor cells.

    Science.gov (United States)

    Noch, Evan; Sariyer, Ilker Kudret; Gordon, Jennifer; Khalili, Kamel

    2012-01-01

    Recent studies have reported the detection of the human neurotropic virus, JCV, in a significant population of brain tumors, including medulloblastomas. Accordingly, expression of the JCV early protein, T-antigen, which has transforming activity in cell culture and in transgenic mice, results in the development of a broad range of tumors of neural crest and glial origin. Evidently, the association of T-antigen with a range of tumor-suppressor proteins, including p53 and pRb, and signaling molecules, such as β-catenin and IRS-1, plays a role in the oncogenic function of JCV T-antigen. We demonstrate that T-antigen expression is suppressed by glucose deprivation in medulloblastoma cells and in glioblastoma xenografts that both endogenously express T-antigen. Mechanistic studies indicate that glucose deprivation-mediated suppression of T-antigen is partly influenced by 5'-activated AMP kinase (AMPK), an important sensor of the AMP/ATP ratio in cells. In addition, glucose deprivation-induced cell cycle arrest in the G1 phase is blocked with AMPK inhibition, which also prevents T-antigen downregulation. Furthermore, T-antigen prevents G1 arrest and sustains cells in the G2 phase during glucose deprivation. On a functional level, T-antigen downregulation is partially dependent on reactive oxygen species (ROS) production during glucose deprivation, and T-antigen prevents ROS induction, loss of ATP production, and cytotoxicity induced by glucose deprivation. Additionally, we have found that T-antigen is downregulated by the glycolytic inhibitor, 2-deoxy-D-glucose (2-DG), and the pentose phosphate inhibitors, 6-aminonicotinamide and oxythiamine, and that T-antigen modulates expression of the glycolytic enzyme, hexokinase 2 (HK2), and the pentose phosphate enzyme, transaldolase-1 (TALDO1), indicating a potential link between T-antigen and metabolic regulation. These studies point to the possible involvement of JCV T-antigen in medulloblastoma proliferation and the metabolic

  4. Skewing to the LFA-3 adhesion pathway by influenza infection of antigen-presenting cells

    NARCIS (Netherlands)

    van Kemenade, F. J.; Kuijpers, K. C.; de Waal-Malefijt, R.; van Lier, R. A.; Miedema, F.

    1993-01-01

    The effect of influenza (FLU) infection on heterotypic conjugate formation between antigen-presenting cells and T lymphocytes has been studied with FLU-specific T cell clones and FLU-infected B-lymphoblastoid cells (B-LCL). Conjugate formation between FLU-infected B-LCL (FLU+ B-LCL) and T cells was

  5. Classing it up to get noticed : MHC class 1 antigen display in dendritic cells and neuroblastoma

    NARCIS (Netherlands)

    Spel, Lotte

    2018-01-01

    In this thesis I have explored the process of MHC-1-mediated antigen presentation in two distinctive cell types: dendritic cells and neuroblastoma tumor cells. Dendritic cells (DCs) are pivotal players that bridge innate and adaptive immunity. DCs are able to engulf tumor-derived material and

  6. Distribution of red blood cell antigens in drug-resistant and drug ...

    African Journals Online (AJOL)

    sofo

    Kramnik , 2000; Gra, 2010; Abel,. 2000). Among the various factors that contribute to a person's genetic individuality are antigens that are the major alloantigen in humans, attached to surface of red blood cells and naturally occurring antibodies ...

  7. Competition for antigen at the level of the antigen presenting cell is a major determinant of immunodominance during memory inflation in murine cytomegalovirus infection

    Science.gov (United States)

    Farrington, Lila A.; Smith, Tameka A.; Grey, Finn; Hill, Ann B.; Snyder, Christopher M.

    2013-01-01

    Cytomegalovirus’s (CMV’s) unique ability to drive the expansion of virus-specific T-cell populations over the course of a lifelong, persistent infection has generated interest in the virus as a potential vaccine strategy. When designing CMV-based vaccine vectors to direct immune responses against HIV or tumor antigens, it becomes important to understand how and why certain CMV-specific populations are chosen to inflate over time. To investigate this, we designed recombinant murine cytomegaloviruses (MCMV) encoding a SIINFEKL-eGFP fusion protein under the control of endogenous immediate early promoters. When mice were infected with these viruses, T cells specific for the SIINFEKL epitope inflated and profoundly dominated T cells specific for non-recombinant (i.e. MCMV-derived) antigens. Moreover, when the virus encoded SIINFEKL, T cells specific for non-recombinant antigens displayed a phenotype indicative of less frequent exposure to antigen. The immunodominance of SIINFEKL-specific T cells could not be altered by decreasing the number of SIINFEKL-specific cells available to respond, or by increasing the number of cells specific for endogenous MCMV antigens. In contrast, coinfection with viruses expressing and lacking SIINFEKL enabled co-inflation of T cells specific for both SIINFEKL and non-recombinant antigens. Because coinfection allows presentation of SIINFEKL and MCMV-derived antigens by different cells within the same animal, these data reveal that competition for, or availability of, antigen at the level of the antigen presenting cell determines the composition of the inflationary response to MCMV. SIINFEKL’s strong affinity for H2-Kb, and its early and abundant expression, may provide this epitope’s competitive advantage. PMID:23455500

  8. Lack of radioimmunodetection and complications associated with monoclonal anticarcinoembryonic antigen antibody cross-reactivity with an antigen on circulating cells

    International Nuclear Information System (INIS)

    Dillman, R.O.; Beauregard, J.C.; Sobol, R.E.; Royston, I.; Bartholomew, R.M.; Hagan, P.S.; Halpern, S.E.

    1984-01-01

    Characterization of several high-affinity murine monoclonal anticarcinoembryonic antigen (CEA) antibodies suggested good specificity except for cross-reactivity with an antigen on granulocytes and erythrocytes which was different from the previously described normal cross-reacting antigen of granulocytes. In vivo studies in athymic mice using an indium conjugate of an anti-CEA monoclonal antibody (MoAb) revealed excellent specific uptake in colorectal carcinoma xenografts. Studies were conducted in humans to determine the limitations produced by the cross-reactivity with granulocytes and erythrocytes. Patients with metastatic colorectal cancer received 3 to 6 mg of anti-CEA MoAb over 10 min or 2 hr. In five of six trials, the MoAb infusion was associated with a 40 to 90% decrease in circulating granulocytes and systemic toxicity including fever, rigors, and emesis. One patient had no change in cell count and had no toxicity. Radionuclide scans with 111 In-anti-CEA MoAb showed marked uptake in the spleen when cells were eliminated, and in the liver, especially when pretreatment CEA levels were high. Metastatic tumor sites failed to concentrate the isotope. This study emphasizes the potential limitations for radioimmunodetection and/or radioimmunotherapy imposed by reactivity with circulating cells, and suggests that certain toxic reactions associated with MoAb infusions are related to destruction of circulating cells rather than allergic reactions to mouse protein. It also emphasizes how variables such as dose and binding affinity of antibody, radioisotope used, and assessment at different observation points can obscure lack of antibody specificity

  9. Lack of radioimmunodetection and complications associated with monoclonal anticarcinoembryonic antigen antibody cross-reactivity with an antigen on circulating cells

    Energy Technology Data Exchange (ETDEWEB)

    Dillman, R.O.; Beauregard, J.C.; Sobol, R.E.; Royston, I.; Bartholomew, R.M.; Hagan, P.S.; Halpern, S.E.

    1984-05-01

    Characterization of several high-affinity murine monoclonal anticarcinoembryonic antigen (CEA) antibodies suggested good specificity except for cross-reactivity with an antigen on granulocytes and erythrocytes which was different from the previously described normal cross-reacting antigen of granulocytes. In vivo studies in athymic mice using an indium conjugate of an anti-CEA monoclonal antibody (MoAb) revealed excellent specific uptake in colorectal carcinoma xenografts. Studies were conducted in humans to determine the limitations produced by the cross-reactivity with granulocytes and erythrocytes. Patients with metastatic colorectal cancer received 3 to 6 mg of anti-CEA MoAb over 10 min or 2 hr. In five of six trials, the MoAb infusion was associated with a 40 to 90% decrease in circulating granulocytes and systemic toxicity including fever, rigors, and emesis. One patient had no change in cell count and had no toxicity. Radionuclide scans with /sup 111/In-anti-CEA MoAb showed marked uptake in the spleen when cells were eliminated, and in the liver, especially when pretreatment CEA levels were high. Metastatic tumor sites failed to concentrate the isotope. This study emphasizes the potential limitations for radioimmunodetection and/or radioimmunotherapy imposed by reactivity with circulating cells, and suggests that certain toxic reactions associated with MoAb infusions are related to destruction of circulating cells rather than allergic reactions to mouse protein. It also emphasizes how variables such as dose and binding affinity of antibody, radioisotope used, and assessment at different observation points can obscure lack of antibody specificity.

  10. 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. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. 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.

  12. The antigen processing machinery of class I human leukocyte antigens: linked patterns of gene expression in neoplastic cells.

    Science.gov (United States)

    Giorda, Ezio; Sibilio, Leonardo; Martayan, Aline; Moretti, Sara; Venturo, Irene; Mottolese, Marcella; Ferrara, Giovan Battista; Cappellacci, Sandra; Eibenschutz, Laura; Catricalà, Caterina; Grammatico, Paola; Giacomini, Patrizio

    2003-07-15

    The ultimate outcome of an immune response (escape or surveillance) depends on a delicate balance of opposing signals delivered by activating and inhibitory immune receptors expressed by cytotoxic T lymphocytes and natural killer cells. In this light, loss and down-regulation of human leukocyte antigens (HLA) class I molecules, while important for keeping tumors below the T-cell detection levels, may incite recognition of missing self. Conversely, the maintenance of normal levels of expression (or even up-regulation) may be favorable to tumors, at least in certain cases. In this study, we took advantage of a previously characterized panel of 15 early passage tumor cell lines (mainly from melanoma and lung carcinoma lesions) enriched with class I-low phenotypes. These cells were systematically characterized by Northern and/or Western blotting (e.g., mini-transcriptome/mini-proteome analysis) for the expression of HLA-A, -B, -C, beta(2)-microglobulin, and the members of the "antigen processing machinery" of class I molecules (LMP2, LMP7, TAP1, TAP2, tapasin, calreticulin, calnexin, and ERp57). In addition, we established four pairs of cultures, each comprising melanoma cells and normal melanocytes from the same patient. We found that approximately 97% of the 185 tested gene products are expressed (although often weakly), and in many cases coordinately regulated in 18 of 19 tumor cell lines. Linked expression patterns could be hierarchically arranged by statistical methods and graphically described as a class I HLA "coordinome." Deviations (both down- and up-regulation) from the coordinome expression pattern inherited from the normal, paired melanocyte counterpart, were allowed but limited in magnitude, as if melanoma cells were trying to keep a "low profile" HLA phenotype. We conclude that irreversible HLA loss is a rare event, and class I expression in tumor cells almost invariably results from reversible gene regulatory (rather than gene disruption) events.

  13. Identification of a second T-cell antigen receptor in human and mouse by an anti-peptide γ-chain-specific monoclonal antibody

    International Nuclear Information System (INIS)

    Ioannides, C.G.; Itoh, K.; Fox, F.E.; Pahwa, R.; Good, R.A.; Platsoucas, C.D.

    1987-01-01

    The authors developed a monoclonal antibody (mAb) (9D7) against a synthetic peptide (P13K) selected from the deduced amino acid sequence of the constant region of the λ chain of the murine T-cell antigen receptor (TCR) (amino acids 118-130). Using this mAb, they identified a putative second TCR expressed on peripheral blood lymphocytes from a patient with severe combined immunodeficiency (SCID) that were propagated in culture with recombinant interleukin 2 (rIL-2) and Con A. This mAb immunoprecipitated two polypeptide chains of 40 and 58 kDa under nonreducing conditions and of 40 and 56 kDa under reducing conditions from 125 I-labeled denatured lysates of T3 + WT31 - lymphocytes expanded in culture from a SCID patient. Chemical crosslinking of 125 I-labeled cells followed by immunoprecipitation with anti-Leu-4 mAb under nonreducing or reducing conditions revealed that the 40- and 56-kDa polypeptide chains were associated with the T3 differentiation antigen. These experiments were done with polyclonal cell populations. Cloned T3 + WT31 - cell populations are required to determine whether the TCR contains two λ polypeptide chains. Using the same 9D7 anti-P18K mAb and immunoblotting analysis, they identified a 35 kDa γ-chain polypeptide under reducing conditions expressed on purified L3T4 - Lyt2 - BALB/c mouse thymocytes. This γ-chain TCR is disulfide linked and has a molecular mass of 80 kDa under nonreducing conditions

  14. Shedding of leukemia-associated P24 antigen by lymphoblastoid cell lines.

    Science.gov (United States)

    Komada, Y; Ochiai, H; Shimizu, K; Azuma, E; Kamiya, H; Sakurai, M

    1987-12-01

    We report the development of a unique enzyme-linked immunosorbent assay (ELISA) which makes possible the detection of leukemia-associated P24 antigen, utilizing its ability to bind the Ricinus communis agglutinin (RCA1) and a monoclonal antibody, SJ-9A4 simultaneously. Using the RCA1/SJ-9A4-ELISA, P24 antigen, as few as 50 X 10(3) cells from a common acute lymphoblastic leukemia (C-ALL) cell line could be detected. The presence of D-galactose gave complete and specific inhibition of P24 antigen binding to RCA1. Matched concentrations of D-glucose and D-sucrose had no effect on binding. The release of the P24 antigen into the culture medium by a C-ALL cell line maintained at 37 degrees C could be detected; however, no P24 antigen was present in the culture medium when the cells were maintained at 4 degrees C. Sequential analysis of the culture medium for soluble P24 antigen revealed that release of the P24 antigen associated with cell growth. Molecular sieve chromatography of concentrated culture medium indicated that shed P24 antigen was eluted in the macromolecule fraction. P24 antigen was detected in the cerebrospinal fluid (CSF) of four patients with P24 positive ALL at the time of relapse of the central nervous system (CNS) and was undetectable while in complete remission. The CSF from three patients with P24 negative ALL and three patients with aseptic meningitis had no detectable activity.

  15. In Vitro Use of Autologous Dendritic Cells Improves Detection of T Cell Responses to Hepatitis B Virus (HBV) Antigens

    NARCIS (Netherlands)

    Carotenuto, Patrizia; Artsen, Andre; Niesters, Hubert G.; Osterhaus, Albert D.; Pontesilli, Oscar

    T lymphocyte responses to hepatitis B virus (HBV) core antigen (HBcAg) are vigorous and easily detectable in vitro during recovery from acute hepatitis B but significantly weaker in patients with chronic HBV infection. In contrast, T cell responses to hepatitis B surface antigen (HBsAg) are almost

  16. Effect of BSA Antigen Sensitization during the Acute Phase of Influenza A Viral Infection on CD11c+ Pulmonary Antigen Presenting Cells

    Directory of Open Access Journals (Sweden)

    Fumitaka Sato

    2009-01-01

    Conclusions: BSA antigen sensitization during the acute phase of influenza A viral infection enhanced IL-10 production from naive CD4+ T cell interaction with CD11c+ pulmonary APCs. The IL-10 secretion evoked Th2 responses in the lungs with downregulation of Th1 responses and was important for the eosinophil recruitment into the lungs after BSA antigen challenge.

  17. The prognostic benefit of tumour-infiltrating Natural Killer cells in endometrial cancer is dependent on concurrent overexpression of Human Leucocyte Antigen-E in the tumour microenvironment

    NARCIS (Netherlands)

    Versluis, M. A. C.; Marchal, S.; Plat, A.; de Bock, G. H.; van Hall, T.; de Bruyn, M.; Hollema, H.; Nijman, H. W.

    2017-01-01

    Background: Human Leucocyte Antigen-E (HLA-E) has been reported as both a positive and negative prognostic marker in cancer. This apparent discrepancy may be due to opposing actions of HLA-E on tumour-infiltrating immune cells. Therefore, we evaluated HLA-E expression and survival in relation to the

  18. Endoplasmic reticulum resident protein of 90 kilodaltons associates with the T- and B-cell antigen receptors and major histocompatibility complex antigens during their assembly

    NARCIS (Netherlands)

    Hochstenbach, F.; DAVID, V.; WATKINS, S.; Brenner, M. B.

    1992-01-01

    In the endoplasmic reticulum (ER), newly synthesized subunits of the T-cell antigen receptor (TCR), membrane-bound immunoglobulin (mIg), and major histocompatibility complex (MHC) class I antigens must fold correctly and assemble completely into multimeric protein complexes prior to transport to the

  19. Flow cytometric assay detecting cytotoxicity against human endogenous retrovirus antigens expressed on cultured multiple sclerosis cells

    DEFF Research Database (Denmark)

    Møller-Larsen, A; Brudek, T; Petersen, T

    2013-01-01

    expressing increased amounts of human endogenous retrovirus antigens. MS patients also have increased antibody levels to these antigens. The target cells are spontaneously growing peripheral blood mononuclear cells (PBMCs) of B cell lineage, expressing human endogenous retrovirus HERV epitopes...... on their surface. Polyclonal antibodies against defined peptides in the Env- and Gag-regions of the HERVs were raised in rabbits and used in antibody-dependent cell-mediated cytotoxicity (ADCC) -assays. Rituximab® (Roche), a chimeric monoclonal antibody against CD20 expressed primarily on B cells, was used...

  20. Killer artificial antigen-presenting cells: the synthetic embodiment of a 'guided missile'.

    Science.gov (United States)

    Schütz, Christian; Oelke, Mathias; Schneck, Jonathan P; Mackensen, Andreas; Fleck, Martin

    2010-07-01

    At present, the treatment of T-cell-dependent autoimmune diseases relies exclusively on strategies leading to nonspecific suppression of the immune systems causing a substantial reduced ability to control concomitant infections or malignancies. Furthermore, long-term treatment with most drugs is accompanied by several serious adverse effects and does not consequently result in cure of the primary immunological malfunction. By contrast, antigen-specific immunotherapy offers the potential to achieve the highest therapeutic efficiency in accordance with minimal adverse effects. Therefore, several studies have been performed utilizing antigen-presenting cells specifically engineered to deplete allo- or antigen-specific T cells ('guided missiles'). Many of these strategies take advantage of the Fas/Fas ligand signaling pathway to efficiently induce antigen-presenting cell-mediated apoptosis in targeted T cells. In this article, we discuss the advantages and shortcomings of a novel non-cell-based 'killer artificial antigen-presenting cell' strategy, developed to overcome obstacles related to current cell-based approaches for the treatment of T-cell-mediated autoimmunity.

  1. Codelivery of antigen and an immune cell adhesion inhibitor is necessary for efficacy of soluble antigen arrays in experimental autoimmune encephalomyelitis

    Directory of Open Access Journals (Sweden)

    Joshua O Sestak

    2014-01-01

    Full Text Available Autoimmune diseases such as multiple sclerosis (MS are typified by the misrecognition of self-antigen and the clonal expansion of autoreactive T cells. Antigen-specific immunotherapies (antigen-SITs have long been explored as a means to desensitize patients to offending self-antigen(s with the potential to retolerize the immune response. Soluble antigen arrays (SAgAs are composed of hyaluronic acid (HA cografted with disease-specific autoantigen (proteolipid protein peptide and an ICAM-1 inhibitor peptide (LABL. SAgAs were designed as an antigen-SIT that codeliver peptides to suppress experimental autoimmune encephalomyelitis (EAE, a murine model of MS. Codelivery of antigen and cell adhesion inhibitor (LABL conjugated to HA was essential for SAgA treatment of EAE. Individual SAgA components or mixtures thereof reduced proinflammatory cytokines in cultured splenocytes from EAE mice; however, these treatments showed minimal to no in vivo therapeutic effect in EAE mice. Thus, carriers that codeliver antigen and a secondary “context” signal (e.g., LABL in vivo may be an important design criteria to consider when designing antigen-SIT for autoimmune therapy.

  2. 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

  3. Immune responses of dendritic cells after acquiring antigen from apoptotic hepatocholangioma cells caused by γ-ray

    International Nuclear Information System (INIS)

    Wu Gang; Gu Hongguang; Han Benli; Pei Xuetao

    2002-01-01

    Objective: To investigate the induction of cytotoxic T lymphocytes (CTLs) in antitumor responsiveness and therapeutic effects after dendritic cells (DCs) acquired antigen from apoptotic hepatocholangioma cells. Methods: DCs from blood mononuclear cells that maintain the characteristics of immaturity-anti-gen-capturing and-processing capacity were established in vitro by using granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-4. Then, apoptosis in hepatocholangioma cells was induced with γ-radiation. The experimental groups included (1) co-culture of DCs, and apoptotic cancer cells and T cells; (2) co-culture of DCs necrotic cancer cells and T cells; (3) co-culture of DCs-cultured cancer cell and T cells. These cells were co-cultured for 7 days. DCs and T cell were enriched separately. Finally, antitumor response test was carried out. Results: These cells had typical dendritic morphology, expressed high levels of CD1a, B7 and acquired antigen from apoptotic cells caused by γ-rays and induced an increased T cell-stimulatory capacity in MLR. Conclusions: DCs obtained from blood mononuclear cells using GM-CSF and IL-4 and DCs can efficiently present antigen driven from apoptotic cells caused by γ-rays and induce T cells increasing obviously. It can probably become an effective approach of DC transduction with antigen

  4. Shedding of CD9 antigen into cerebrospinal fluid by acute lymphoblastic leukemia cells.

    Science.gov (United States)

    Komada, Y; Ochiai, H; Shimizu, K; Azuma, E; Kamiya, H; Sakurai, M

    1990-07-01

    The accurate identification of small numbers of leukemic cells in the cerebrospinal fluid (CSF) presents a diagnostic problem in the treatment of acute lymphoblastic leukemia (ALL). We demonstrated that soluble CD9 antigen was shed into CSF obtained from children with ALL, using enzyme-linked immunosorbent assay (ELISA), which used the activity of CD9 antigen to bind the Ricinus communis agglutinin (RCA1) and a monoclonal antibody, SJ-9A4, simultaneously. Using RCA1/SJ-9A4 ELISA, CD9 antigen was detectable in CSF but not in plasma from 12 cases of CD9+ ALL in central nervous system (CNS) relapse. However, CD9 antigen was not released into CSF from 11 cases of CD9- ALL with CNS involvement, 136 cases of CD9+ ALL in complete remission (CR), 29 cases of CD9- ALL in CR, or 21 cases of aseptic meningitis. Interestingly, the levels of CD9 antigen were elevated in CSF from 7 of 10 CD9+ ALL patients without cytologically proven CNS involvement at diagnosis, with subsequent return to undetectable levels after initial induction chemotherapy was begun. In addition, sequential analysis of CSF from a 5-year-old boy with CD9+ ALL in CNS relapse showed that levels of CD9 antigen correlated well with the number of leukemic cells in CSF. Serial quantitative analysis of CD9 antigen in CSF could be useful to detect the proliferation of residual leukemic cells before the clinical manifestation.

  5. Antigen presentation and MHC class II expression by human esophageal epithelial cells: role in eosinophilic esophagitis.

    Science.gov (United States)

    Mulder, Daniel J; Pooni, Aman; Mak, Nanette; Hurlbut, David J; Basta, Sameh; Justinich, Christopher J

    2011-02-01

    Professional antigen-presenting cells (APCs) play a crucial role in initiating immune responses. Under pathological conditions, epithelial cells at mucosal surfaces act as nonprofessional APCs, thereby regulating immune responses at the site of exposure. Epithelial cells in the esophagus may contribute to the pathogenesis of eosinophilic esophagitis (EoE) by presenting antigens on the major histocompatibility complex (MHC) class II. Our goal was to demonstrate the ability of esophageal epithelial cells to process and present antigens on the MHC class II system and to investigate the contribution of epithelial cell antigen presentation to EoE. Immunohistochemistry detected HLA-DR, CD80, and CD86 expression and enzyme-linked immunosorbent assay detected interferon-γ (IFNγ) in esophageal biopsies. Antigen presentation was studied using the human esophageal epithelial cell line HET-1A by reverse transcriptase-PCR, flow cytometry, and confocal microscopy. T helper cell lymphocyte proliferation was assessed by flow cytometry and IL-2 secretion. IFNγ and MHC class II were increased in mucosa of patients with EoE. IFNγ increased mRNA of HLA-DP, HLA-DQ, HLA-DR, and CIITA in HET-1A cells. HET-1A engulfed cell debris and processed ovalbumin. HET-1A cells expressed HLA-DR after IFNγ treatment. HET-1A stimulated T helper cell activation. In this study, we demonstrated the ability of esophageal epithelial cells to act as nonprofessional APCs in the presence of IFNγ. Esophageal epithelial cell antigen presentation may contribute to the pathophysiology of eosinophilic esophagitis. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  6. 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....

  7. T-cell dysregulation caused by chronic antigenic stress: the role of CMV in immunosenescence?

    Science.gov (United States)

    Pawelec, Graham; Gouttefangeas, Cécile

    2006-04-01

    Dysfunctional T-cell immunity contributes to susceptibility to infectious disease in the elderly. A characteristic feature of this "immunosenescence" is the predominance of clonal expansions of CD8 cells and decreased diversity of the T-cell antigen receptor repertoire. Lifelong chronic antigenic stress commonly caused by infection with persistent activating herpes viruses causes the accumulation of anergic, apoptosis-resistant CD8 T cells. These dysfunctional cells are indirectly immunosuppressive by tasking up the "immunological space" as well as directly suppressive via blockade of antigen presenting cells or cytokine secretion. They are associated with an emerging "immunological risk profile" predicting mortality in longitudinal studies of very old people. It is therefore hypothesized that for that majority of elderly people infected with cytomegalovirus (CMV), which seems to act as the dominant chronic stressor, anti-viral strategies would be of benefit in abrogating some of the detrimental clinical manifestations of immunosenescence.

  8. 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 a particular interest in developing robust high-throughput assays as chicken vaccine trials usually comprise many individuals. In many respects, the avian immune system differs from the mammalian, and T cell assessment protocols must be adjusted accordingly to account for, e.g., differences in leukocyte...... 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...

  9. Breadth of T cell responses after immunization with adenovirus vectors encoding ancestral antigens or polyvalent papillomavirus antigens

    DEFF Research Database (Denmark)

    Ragonnaud, Emeline; Pedersen, Anders Gorm; Holst, Peter Johannes

    2017-01-01

    - either by inducing cross-reactive T cells or by administering a polyvalent vaccine. To test these strategies, we designed 3 ancestral and 2 circulating sequences based on the two domains of the E1 and E2 proteins of papillomaviruses (PVs) that exhibit the highest degree of conservation in comparison...... circulating strains and a putative ancestor of oncogenic HPVs, we showed that the ancestral vaccine antigen has to be approximately 90% identical to the circulating PVs before a marked drop of ~90% mean CD8+ T cell responses ensues. Interestingly, the combination of two or three type-specific PV vaccines did...... not induce a significant decrease of the CD8+ T cell response to the individual targeted PV types. Polyvalent HPV vaccine based on the E1 and E2 proteins seem to be capable of triggering responses towards more than one type of PV while the cross-reactivity of ancestral vaccine seems insufficient...

  10. Immunochemical Investigations of Cell Surface Antigens of Anaerobic Bacteria.

    Science.gov (United States)

    1976-01-15

    has also been visulalized . With use of a radioactive anti’qen bindinq assay, antibody to this capsularpolysaccharide has been demonstrated in anti- sera...With many bacteria, serogrouning is based on cansular oolysaccharide antigens. Serogrouping has led to much valuable epidemiologic information

  11. Carbohydrates as T-cell antigens with implications in health and disease.

    Science.gov (United States)

    Sun, Lina; Middleton, Dustin R; Wantuch, Paeton L; Ozdilek, Ahmet; Avci, Fikri Y

    2016-10-01

    Glycosylation is arguably the most ubiquitous post-translational modification on proteins in microbial and mammalian cells. During the past few years, there has been intensive research demonstrating that carbohydrates, either in pure forms or in conjunction with proteins or lipids, evoke and modulate adaptive immune responses. We now know that carbohydrates can be directly recognized by T cells or participate in T-cell stimulation as components of T-cell epitopes. T-cell recognition of carbohydrate antigens takes place via their presentation by major histocompatibility complex pathways on antigen-presenting cells. In this review, we summarize studies on carbohydrates as T-cell antigens modulating adaptive immune responses. Through discussion of glycan-containing antigens, such as glycoproteins, glycolipids, zwitterionic polysaccharides and carbohydrate-based glycoconjugate vaccines, we will illustrate the key molecular and cellular interactions between carbohydrate antigens and T cells and the implications of these interactions in health and disease. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Killer artificial antigen-presenting cells: the synthetic embodiment of a ‘guided missile’

    Science.gov (United States)

    Schütz, Christian; Oelke, Mathias; Schneck, Jonathan P; Mackensen, Andreas; Fleck, Martin

    2010-01-01

    At present, the treatment of T-cell-dependent autoimmune diseases relies exclusively on strategies leading to nonspecific suppression of the immune systems causing a substantial reduced ability to control concomitant infections or malignancies. Furthermore, long-term treatment with most drugs is accompanied by several serious adverse effects and does not consequently result in cure of the primary immunological malfunction. By contrast, antigen-specific immunotherapy offers the potential to achieve the highest therapeutic efficiency in accordance with minimal adverse effects. Therefore, several studies have been performed utilizing antigen-presenting cells specifically engineered to deplete allo- or antigen-specific T cells (‘guided missiles’). Many of these strategies take advantage of the Fas/Fas ligand signaling pathway to efficiently induce antigen-presenting cell-mediated apoptosis in targeted T cells. In this article, we discuss the advantages and shortcomings of a novel non-cell-based ‘killer artificial antigen-presenting cell’ strategy, developed to overcome obstacles related to current cell-based approaches for the treatment of T-cell-mediated autoimmunity. PMID:20636007

  13. 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

  14. CD1c tetramers detect ex vivo T cell responses to processed phosphomycoketide antigens

    NARCIS (Netherlands)

    Ly, Dalam; Kasmar, Anne G.; Cheng, Tan-Yun; de Jong, Annemieke; Huang, Shouxiong; Roy, Sobhan; Bhatt, Apoorva; van Summeren, Ruben P.; Altman, John D.; Jacobs, William R.; Adams, Erin J.; Minnaard, Adriaan J.; Porcelli, Steven A.; Moody, Branch; Jacobs Jr., William R.

    2013-01-01

    CD1c is expressed with high density on human dendritic cells (DCs) and B cells, yet its antigen presentation functions are the least well understood among CD1 family members. Using a CD1c-reactive T cell line (DN6) to complete an organism-wide survey of M. tuberculosis lipids, we identified C32

  15. Modulation of carcinoembryonic antigen release by glucosylceramide : Implications for HT29 cell differentiation

    NARCIS (Netherlands)

    Babia, T; Hoekstra, D; Kok, JW; Veldman, Robert

    1998-01-01

    Previous work suggested that glucosylceramide (GlcCer) plays a role in the regulation of cell differentiation of HT29 human colon tumor cells [I]. In the present study, we investigated the role of GlcCer in the cellular release of carcinoembryonic antigen (CEA), a marker for cell differentiation.

  16. Phosphatase and tensin homolog (PTEN) in antigen-presenting cells controls Th17-mediated autoimmune arthritis

    NARCIS (Netherlands)

    Bluml, S.; Sahin, E.; Saferding, V.; Goncalves-Alves, E.; Hainzl, E.; Niederreiter, B.; Hladik, A.; Lohmeyer, T.; Brunner, J.S.; Bonelli, M.; Koenders, M.I.; Berg, W.B. van den; Superti-Furga, G.; Smolen, J.S.; Schabbauer, G.; Redlich, K.

    2015-01-01

    INTRODUCTION: Autoreactive T cells are a central element in many systemic autoimmune diseases. The generation of these pathogenic T cells is instructed by antigen-presenting cells (APCs). However, signaling pathways in APCs that drive autoimmune diseases, such as rheumatoid arthritis, are not

  17. 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

  18. A new Kupffer cell receptor mediating plasma clearance of carcinoembryonic antigen by the rat.

    Science.gov (United States)

    Toth, C A; Thomas, P; Broitman, S A; Zamcheck, N

    1982-01-01

    Native human carcinoembryonic antigen is rapidly removed from the circulation by the rat liver Kupffer cell after intravenous injection. The molecule is subsequently transferred to the hepatocyte in an immunologically identifiable form. Carcinoembryonic antigen has a circulatory half-life of 3.7 (+/- 0.8) min, and cellular entry is by receptor-mediated endocytosis. Non-specific fluid pinocytosis and phagocytosis can be excluded as possible mechanisms by the kinetics of clearance and failure of colloidal carbon to inhibit uptake. Substances with known affinity for the hepatic receptors for mannose, N-acetylglucosamine, fucose and galactose all fail to inhibit carcinoembryonic antigen clearance. After two cycles of the Smith degradation, carcinoembryonic antigen is still able to inhibit clearance of the native molecule. Receptor specificity is apparently not dependent on those non-reducing terminal sugars of the native molecule. Performic acid-oxidized carcinoembryonic antigen also inhibits clearance of carcinoembryonic antigen in vivo. Receptor binding is not dependent on tertiary protein conformation. Non-specific cross-reacting antigen, a glycoprotein structurally similar to carcinoembryonic antigen, is cleared by the same mechanism. PMID:6896821

  19. Prevention of B cell antigen receptor-induced apoptosis by ligation of CD40 occurs downstream of cell cycle regulation

    NARCIS (Netherlands)

    Mackus, Wendelina J. M.; Lens, Susanne M. A.; Medema, René H.; Kwakkenbos, Mark J.; Evers, Ludo M.; Oers, Marinus H. J. van; van Lier, René A. W.; Eldering, Eric

    2002-01-01

    Cross-linking of the B cell antigen receptor (BCR) on germinal center B cells can induce growth arrest and apoptosis, thereby eliminating potentially autoreactive B cells. Using the Burkitt lymphoma cell line Ramos as a model, we studied the commitment to apoptosis following growth arrest, as well

  20. Heat shock protein-90 inhibitors enhance antigen expression on melanomas and increase T cell recognition of tumor cells.

    Directory of Open Access Journals (Sweden)

    Timothy J Haggerty

    Full Text Available In an effort to enhance antigen-specific T cell recognition of cancer cells, we have examined numerous modulators of antigen-expression. In this report we demonstrate that twelve different Hsp90 inhibitors (iHsp90 share the ability to increase the expression of differentiation antigens and MHC Class I antigens. These iHsp90 are active in several molecular and cellular assays on a series of tumor cell lines, including eleven human melanomas, a murine B16 melanoma, and two human glioma-derived cell lines. Intra-cytoplasmic antibody staining showed that all of the tested iHsp90 increased expression of the melanocyte differentiation antigens Melan-A/MART-1, gp100, and TRP-2, as well as MHC Class I. The gliomas showed enhanced gp100 and MHC staining. Quantitative analysis of mRNA levels showed a parallel increase in message transcription, and a reporter assay shows induction of promoter activity for Melan-A/MART-1 gene. In addition, iHsp90 increased recognition of tumor cells by T cells specific for Melan-A/MART-1. In contrast to direct Hsp90 client proteins, the increased levels of full-length differentiation antigens that result from iHsp90 treatment are most likely the result of transcriptional activation of their encoding genes. In combination, these results suggest that iHsp90 improve recognition of tumor cells by T cells specific for a melanoma-associated antigen as a result of increasing the expressed intracellular antigen pool available for processing and presentation by MHC Class I, along with increased levels of MHC Class I itself. As these Hsp90 inhibitors do not interfere with T cell function, they could have potential for use in immunotherapy of cancer.

  1. 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.

  2. Antigen entrapped in the escheriosomes leads to the generation of CD4(+) helper and CD8(+) cytotoxic T cell response.

    Science.gov (United States)

    Syed, Faisal M; Khan, Masood A; Nasti, Tahseen H; Ahmad, Nadeem; Mohammad, Owais

    2003-06-02

    In previous study, we demonstrated the potential of Escherichia coli (E. coli) lipid liposomes (escheriosomes) to undergo membrane-membrane fusion with cytoplasmic membrane of the target cells including professional antigen presenting cells. Our present study demonstrates that antigen encapsulated in escheriosomes could be successfully delivered simultaneously to the cytosolic as well as endosomal processing pathways of antigen presenting cells, leading to the generation of both CD4(+) T-helper and CD8(+) cytotoxic T cell response. In contrast, encapsulation of same antigen in egg phosphatidyl-choline (egg PC) liposomes, just like antigen-incomplete Freund's adjuvant (IFA) complex, has inefficient access to the cytosolic pathway of MHC I-dependent antigen presentation and failed to generate antigen-specific CD8(+) cytotoxic T cell response. However, both egg PC liposomes as well as escheriosomes-encapsulated antigen elicited strong humoral immune response in immunized animals but antibody titre was significantly higher in the group of animals immunized with escheriosomes-encapsulated antigen. These results imply usage of liposome-based adjuvant as potential candidate vaccine capable of eliciting both cell-mediated as well as humoral immune responses. Furthermore, antigen entrapped in escheriosomes stimulates antigen-specific CD4(+) T cell proliferation and also enhances the level of IL-2, IFN-gamma and IL-4 in the immunized animals.

  3. Dendritic cells from oral cavity induce Foxp3(+ regulatory T cells upon antigen stimulation.

    Directory of Open Access Journals (Sweden)

    Sayuri Yamazaki

    Full Text Available Evidence is accumulating that dendritic cells (DCs from the intestines have the capacity to induce Foxp3(+CD4(+ regulatory T cells (T-regs and regulate immunity versus tolerance in the intestines. However, the contribution of DCs to controlling immunity versus tolerance in the oral cavity has not been addressed. Here, we report that DCs from the oral cavity induce Foxp3(+ T-regs as well as DCs from intestine. We found that oral-cavity-draining cervical lymph nodes contained higher frequencies of Foxp3(+ T-regs and ROR-γt(+ CD4(+T cells than other lymph nodes. The high frequency of Foxp3(+ T-regs in the oral-cavity-draining cervical lymph nodes was not dependent on the Toll like receptor (TLR adaptor molecules, Myd88 and TICAM-1 (TRIF. In contrast, the high frequency of ROR-γt(+ CD4(+T cells relies on Myd88 and TICAM-1. In vitro data showed that CD11c(+ DCs from oral-cavity-draining cervical lymph nodes have the capacity to induce Foxp3(+ T-regs in the presence of antigen. These data suggest that, as well as in the intestinal environment, antigen-presenting DCs may play a vital role in maintaining tolerance by inducing Foxp3(+ T-regs in the oral cavity.

  4. A novel method to generate T-cell receptor-deficient chimeric antigen receptor T cells.

    Science.gov (United States)

    Kamiya, Takahiro; Wong, Desmond; Png, Yi Tian; Campana, Dario

    2018-03-13

    Practical methods are needed to increase the applicability and efficacy of chimeric antigen receptor (CAR) T-cell therapies. Using donor-derived CAR-T cells is attractive, but expression of endogenous T-cell receptors (TCRs) carries the risk for graft-versus-host-disease (GVHD). To remove surface TCRαβ, we combined an antibody-derived single-chain variable fragment specific for CD3ε with 21 different amino acid sequences predicted to retain it intracellularly. After transduction in T cells, several of these protein expression blockers (PEBLs) colocalized intracellularly with CD3ε, blocking surface CD3 and TCRαβ expression. In 25 experiments, median TCRαβ expression in T lymphocytes was reduced from 95.7% to 25.0%; CD3/TCRαβ cell depletion yielded virtually pure TCRαβ-negative T cells. Anti-CD3ε PEBLs abrogated TCRαβ-mediated signaling, without affecting immunophenotype or proliferation. In anti-CD3ε PEBL-T cells, expression of an anti-CD19-41BB-CD3ζ CAR induced cytokine secretion, long-term proliferation, and CD19 + leukemia cell killing, at rates meeting or exceeding those of CAR-T cells with normal CD3/TCRαβ expression. In immunodeficient mice, anti-CD3ε PEBL-T cells had markedly reduced GVHD potential; when transduced with anti-CD19 CAR, these T cells killed engrafted leukemic cells. PEBL blockade of surface CD3/TCRαβ expression is an effective tool to prepare allogeneic CAR-T cells. Combined PEBL and CAR expression can be achieved in a single-step procedure, is easily adaptable to current cell manufacturing protocols, and can be used to target other T-cell molecules to further enhance CAR-T-cell therapies. © 2018 by The American Society of Hematology.

  5. Downregulation of integrin β4 decreases the ability of airway epithelial cells to present antigens.

    Directory of Open Access Journals (Sweden)

    Chi Liu

    Full Text Available Airway epithelial cells have been demonstrated to be accessory antigen presentation cells (APC capable of activating T cells and may play an important role in the development of allergic airway inflammation of asthma. In asthmatic airways, loss of expression of the adhesion molecule integrin β4 (ITGB4 and an increase in Th2 inflammation bias has been observed in our previous study. Given that ITGB4 is engaged in multiple signaling pathways, we studied whether disruption of ITGB4-mediated cell adhesion may contribute to the adaptive immune response of epithelial cells, including their ability to present antigens, induce the activate and differentiate of T cells. We silenced ITGB4 expression in bronchial epithelial cells with an effective siRNA vector and studied the effects of ITGB4 silencing on the antigen presentation ability of airway epithelial cells. T cell proliferation and cytokine production was investigated after co-culturing with ITGB4-silenced epithelial cells. Surface expression of B7 homologs and the major histocompatibility complex (MHC class II was also detected after ITGB4 was silenced. Our results demonstrated that silencing of ITGB4 resulted in impaired antigen presentation processes and suppressed T cell proliferation. Meanwhile, decrease in Th1 cytokine production and increase in Th17 cytokine production was induced after co-culturing with ITGB4-silenced epithelial cells. Moreover, HLA-DR was decreased and the B7 homologs expression was different after ITGB4 silencing. Overall, this study suggested that downregulation of ITGB4 expression in airway epithelial cells could impair the antigen presentation ability of these cells, which further regulate airway inflammation reaction in allergic asthma.

  6. Invariant Chain Modulates HLA Class II Protein Recycling and Peptide Presentation in Nonprofessional Antigen Presenting Cells

    OpenAIRE

    Haque, Azizul; Hajiaghamohseni, Laela M.; Li, Ping; Toomy, Katherine; Blum, Janice S.

    2007-01-01

    The expression of MHC class II molecules and the invariant chain (Ii) chaperone, is coordinately regulated in professional antigen presenting cells (APC). Ii facilitates class II subunit folding as well as transit and retention in mature endosomal compartments rich in antigenic peptides in these APC. Yet, in nonprofessional APC such as tumors, fibroblasts and endocrine tissues, the expression of class II subunits and Ii may be uncoupled. Studies of nonprofessional APC indicate class II molecu...

  7. 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......-gamma secretion showed that the most frequently recognized antigen was ESAT-6, followed by MPT59, GroES, MPB70, MPT64, DnaK, GroEL and PstS. The frequency of ESAT-6 responders, as measured both by proliferation (18/19) and secretion of IFN-gamma (16/19) was comparable to the results obtained with whole-cell M...

  8. Lym-1 Chimeric Antigen Receptor T Cells Exhibit Potent Anti-Tumor Effects against B-Cell Lymphoma.

    Science.gov (United States)

    Zheng, Long; Hu, Peisheng; Wolfe, Brandon; Gonsalves, Caryn; Ren, Luqing; Khawli, Leslie A; Kaslow, Harvey R; Epstein, Alan L

    2017-12-20

    T cells expressing chimeric antigen receptors (CARs) recognizing CD19 epitopes have produced remarkable anti-tumor effects in patients with B-cell malignancies. However, cancer cells lacking recognized epitopes can emerge, leading to relapse and death. Thus, CAR T cells targeting different epitopes on different antigens could improve immunotherapy. The Lym-1 antibody targets a conformational epitope of Human Leukocyte Antigen-antigen D Related (HLA-DR) on the surface of human B-cell lymphomas. Lym-1 CAR T cells were thus generated for evaluation of cytotoxic activity towards lymphoma cells in vitro and in vivo. Human T cells from healthy donors were transduced to express a Lym-1 CAR, and assessed for epitope-driven function in culture and towards Raji xenografts in NOD-scidIL2Rgamma null (NSG) mice. Lym-1 CAR T cells exhibited epitope-driven activation and lytic function against human B-cell lymphoma cell lines in culture and mediated complete regression of Raji/Luciferase-Green fluorescent protein (Raji/Luc-GFP) in NSG mice with similar or better reactivity than CD19 CAR T cells. Lym-1 CAR transduction of T cells is a promising immunotherapy for patients with Lym-1 epitope positive B-cell malignancies.

  9. Lym-1 Chimeric Antigen Receptor T Cells Exhibit Potent Anti-Tumor Effects against B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Long Zheng

    2017-12-01

    Full Text Available T cells expressing chimeric antigen receptors (CARs recognizing CD19 epitopes have produced remarkable anti-tumor effects in patients with B-cell malignancies. However, cancer cells lacking recognized epitopes can emerge, leading to relapse and death. Thus, CAR T cells targeting different epitopes on different antigens could improve immunotherapy. The Lym-1 antibody targets a conformational epitope of Human Leukocyte Antigen-antigen D Related (HLA-DR on the surface of human B-cell lymphomas. Lym-1 CAR T cells were thus generated for evaluation of cytotoxic activity towards lymphoma cells in vitro and in vivo. Human T cells from healthy donors were transduced to express a Lym-1 CAR, and assessed for epitope-driven function in culture and towards Raji xenografts in NOD-scidIL2Rgammanull (NSG mice. Lym-1 CAR T cells exhibited epitope-driven activation and lytic function against human B-cell lymphoma cell lines in culture and mediated complete regression of Raji/Luciferase-Green fluorescent protein (Raji/Luc-GFP in NSG mice with similar or better reactivity than CD19 CAR T cells. Lym-1 CAR transduction of T cells is a promising immunotherapy for patients with Lym-1 epitope positive B-cell malignancies.

  10. The location of splenic NKT cells favours their rapid activation by blood-borne antigen.

    Science.gov (United States)

    Barral, Patricia; Sánchez-Niño, María Dolores; van Rooijen, Nico; Cerundolo, Vincenzo; Batista, Facundo D

    2012-05-16

    Natural killer T (NKT) cells play an important role in mounting protective responses to blood-borne infections. However, though the spleen is the largest blood filter in the body, the distribution and dynamics of NKT cells within this organ are not well characterized. Here we show that the majority of NKT cells patrol around the marginal zone (MZ) and red pulp (RP) of the spleen. In response to lipid antigen, these NKT cells become arrested and rapidly produce cytokines, while the small proportion of NKT cells located in the white pulp (WP) exhibit limited activation. Importantly, disruption of the splenic MZ by chemical or genetic approaches results in a severe reduction in NKT cell activation indicating the need of cooperation between both MZ macrophages and dendritic cells for efficient NKT cell responses. Thus, the location of splenic NKT cells in the MZ and RP facilitates their access to blood-borne antigen and enables the rapid initiation of protective immune responses.

  11. Localization of splenic cells with antigen-transporting capability in the chicken.

    Science.gov (United States)

    del Cacho, E; Gallego, M; Arnal, C; Bascuas, J A

    1995-01-01

    The objective of the present study is to investigate the migration pattern of the splenic dendritic cell of the chicken named the ellipsoid-associated cell (EAC) from the site of initial location at the periphery of the ellipsoid to the splenic T- and B-dependent areas. Bovine serum albumin bound to biotin and conjugated to gold particles was used as a histochemically identifiable antigen detected as a peroxidase reaction. The antigen was intravenously injected, and subsequently its pattern of distribution in a time sequence and within the tissue was examined at the light and electron microscopy levels. In addition, an hour prior to sacrifice, the chickens received a single injection of the thymidine analogue 5-bromo-2'-deoxyuridine, in order to quantify the number of DNA synthesizing cells and to establish a relationship between the migrating EAC and the rate of mitosis in the white pulp. The observations showed that between 12 hours and 3 days after the second antigen administration the labeled EAC, which was first located around the ellipsoid, progressively reached further areas with time towards the periarteriolar lymphoid sheaths, where newly formed germinal centers appeared. Furthermore, the rate of cell proliferation within the white pulp was associated with the arrival of the antigen-transporting EAC. The results suggest that migrating EAC have a role as both antigen-transporting cell and antigen-presenting cell in the T- and B-dependent areas, as a result of which migrating EAC is transiently found in periellipsoidal white pulp, then periarteriolar lymphoid sheaths, and finally germinal centers, where it may function as an interdigitating cell or as a follicular dendritic cell, depending on its location. Thus, we conclude that the EACs are precursors of both interdigitating and follicular dendritic cells.

  12. 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.

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

    Science.gov (United States)

    Rinaldo, Charles R.

    2013-01-01

    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. PMID:24278768

  14. 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. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Feeding dendritic cells with tumor antigens: self-service buffet or à la carte?

    Science.gov (United States)

    Melero, I; Vile, R G; Colombo, M P

    2000-07-01

    Adoptive transfer of autologous dendritic cells (DC) presenting tumor-associated antigens initiate and sustain an immune response which eradicate murine malignancies. Based on these observations, several clinical trials are in progress testing safety and efficacy with encouraging preliminary reports. In these approaches, ex vivo incubation of DC with a source of tumor antigens is required to load the relevant antigenic epitopes on the adequate antigen presenting molecules. Recent data show that in some instances exogenous DC artificially injected into malignant tissue or endogenous DC attracted to the tumor nodule by means of gene transfer of GM-CSF and CD40L into malignant cells result in efficacious antitumor immunity. In the case of intratumoral injection of DC the procedure is curative only if DC had been genetically engineered to produce IL-12, IL-6 or to express CD40L. Evidence has been obtained showing that intratumoral DC can capture and process tumor antigens to be presented to T-lymphocytes. Although the exact mechanisms of tumor antigen acquisition by DC are still unclear, available data suggest a role for heat shock proteins released from dying malignant cells and for the internalization of tumor-derived apoptotic bodies. Roles for tumor necrosis versus apoptosis are discussed in light of the 'danger theory'. Gene Therapy (2000) 7, 1167-1170.

  16. T-Helper Type 2 Cells Direct Antigen-Induced Eosinophilic Skin Inflammation in Mice.

    Science.gov (United States)

    Kaminuma, Osamu; Nishimura, Tomoe; Kitamura, Noriko; Saeki, Mayumi; Hiroi, Takachika; Mori, Akio

    2018-01-01

    Eosinophilic inflammation in combination with immunoglobulin E (IgE) production is a characteristic feature of atopic dermatitis. Although activated T-helper type (Th) 2 cells play critical roles in the local accumulation and activation of eosinophils, whether they induce eosinophilic skin inflammation, independent of the IgE-mediated pathway has been unclear. To address the functional role of T cells in allergic skin diseases, we herein transferred Th1/Th2-differentiated or naive DO11.10 T cells into unprimed BALB/c mice. Ovalbumin-specific Th2 cells, as well as eosinophils, accumulated in the skin upon antigen challenge, despite the absence of antigen-specific IgE. Neither antigen-specific Th1 nor naive T cells induced eosinophil accumulation, although Th1 cells by themselves migrated into the skin. Interleukin (IL)-4, IL-5, and eotaxin were specifically produced in the skin of antigen-challenged, Th2 cell-transferred mice, whereas interferon (IFN)-γ and regulated on activation, normal T cell expressed and secreted (RANTES) were preferentially produced in Th1 cells-transferred mice. Production of monocyte chemoattractant protein (MCP)-1 and MCP-3 was enhanced by both Th1 and Th2 cells. The accumulation of eosinophils and Th2 cells in the skin was suppressed by both dexamethasone and FK506, indicating an essential role of Th2 cells in eosinophil recruitment. We conclude that Th2 cells can induce eosinophilic infiltration into the skin in the absence of antigen-specific IgE. Copyright © 2018 The Korean Academy of Asthma, Allergy and Clinical Immunology · The Korean Academy of Pediatric Allergy and Respiratory Disease.

  17. Suppressor cells in transplantation tolerance. III. The role of antigen in the maintenance of transplantation tolerance

    International Nuclear Information System (INIS)

    Tutschka, P.J.; Hess, A.D.; Beschorner, W.E.; Santos, G.W.

    1982-01-01

    Suppressor cells, which in an alloantigen-specific manner inhibit proliferation of donor cells to host antigens in a mixed lymphocyte culture and adoptively transfer the suppression of graft-versus-host disease (GVHD), undergo a gradual clonal reduction in long-term, allogeneic, histoincompatible rat radiation chimeras until they can no longer be measured in an in vitro suppressor cell assay. When lymphohematopoietic cells from these chimeras are transferred into lethally irradiated secondary recipients of original donor strain, the suppressor cells, now in a target antigen-free environment, undergo a further clonal reduction. After parking for 120 days, the chimeric cells are specifically tolerant to original host antigens, but cannot adoptively transfer suppression of GVHD. When chimeric cells, parked for 120 days in secondary recipients of original donor strain, are stimulated with original host-type antigen repeatedly during or once at the end of the parking period, the suppressor cell clone is expanded, suppressor cells can be identified in vitro, and suppression of GVHD can adoptively be transferred to tertiary recipients

  18. Invariant NKT cells are required for airway inflammation induced by environmental antigens.

    Science.gov (United States)

    Wingender, Gerhard; Rogers, Paul; Batzer, Glenda; Lee, Myung Steve; Bai, Dong; Pei, Bo; Khurana, Archana; Kronenberg, Mitchell; Horner, Anthony A

    2011-06-06

    Invariant NKT cells (iNKT cells) are a unique subset of T lymphocytes that rapidly carry out effector functions. In this study, we report that a majority of sterile house dust extracts (HDEs) tested contained antigens capable of activating mouse and human iNKT cells. HDEs had adjuvant-like properties in an ovalbumin (OVA)-induced asthma model, which were dependent on Vα14i NKT cells, as vaccinated animals deficient for iNKT cells displayed significantly attenuated immune responses and airway inflammation. Furthermore, the administration of HDEs together with OVA mutually augmented the synthesis of cytokines by Vα14i NKT cells and by conventional CD4(+) T cells in the lung, demonstrating a profound immune response synergy for both Th2 cytokines and IL-17A. These data demonstrate that iNKT cell antigens are far more widely dispersed in the environment than previously anticipated. Furthermore, as the antigenic activity in different houses varied greatly, they further suggest that iNKT cell responses to ambient antigens, particular to certain environments, might promote sensitization to conventional respiratory allergens.

  19. Differentiation and major histocompatibility complex antigen expression in human liver-derived stem cells.

    Science.gov (United States)

    Lee, J-H; Park, H-J; Kim, Y-A; Lee, D-H; Noh, J-K; Kwon, C H D; Jung, S-M; Lee, S-K

    2012-05-01

    Stem cells are a promising source for liver repopulation after cell transplantation, but whether the adult liver contains hepatic stem cells is controversial. The purpose of this study was to characterize the properties and expression profile of major histocompatibility complex (MHC) antigens on the surface of human-derived stem cells. Human liver-derived stem cells (HLSC7) were isolated from the nontumorous tissue of a patient who underwent a resection of an hepatic hemangioendothelioma. We characterized HLSC7 using a fluorescence-activated cell sorter, polymerase chain reactions, and immunofluorescence assays. HLSC7 expressed mesenchymal but not hematopoietic stem cell markers. HLSC7 underwent osteogenic, chondrogenic, and hepatogenic differentiation when cultured in appropriate differentiation media. However, HLSC7 did not differentiate into adipocytes. In addition, HLSC7 did not express MHC class II (HLA-DP, -DQ, and -DR) antigens. However, they did express MHC class I antigens. These results suggest that human liver-derived stem cells express MHC class I antigens and thus may be rejected on transplantation. Therefore, in addition to studies on stem cell differentiation, one must overcome immunologic barriers for successful clinical application of this therapy. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Particle shape dependence of CD8+ T cell activation by artificial antigen presenting cells.

    Science.gov (United States)

    Sunshine, Joel C; Perica, Karlo; Schneck, Jonathan P; Green, Jordan J

    2014-01-01

    Previous work developing particle-based acellular, artificial antigen presenting cells (aAPCs) has focused exclusively on spherical platforms. To explore the role of shape, we generated ellipsoidal PLGA microparticles with varying aspect ratios (ARs) and synthesized aAPCs from them. The ellipsoidal biomimetic aAPCs with high-AR showed significantly enhanced in vitro and in vivo activity above spherical aAPCs with particle volume and antigen content held constant. Confocal imaging indicates that CD8+ T cells preferentially migrate to and are activated by interaction with the long axis of the aAPC. Importantly, enhanced activity of high-AR aAPCs was seen in a mouse melanoma model, with high-AR aAPCs improving melanoma survival compared to non-cognate aAPCs (p = 0.004) and cognate spherical aAPCs (p = 0.05). These findings indicate that particle geometry is a critical design criterion in the generation of aAPCs, and may offer insight into the essential role of geometry in the interaction between CD8+ T cells and biological APCs. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Cleo Goyvaerts

    2015-01-01

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

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

    Science.gov (United States)

    Goyvaerts, Cleo; Breckpot, Karine

    2015-01-01

    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.

  3. 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.

  4. Sustained accumulation of antigen-presenting cells after infection promotes local T-cell immunity.

    Science.gov (United States)

    Collins, Nicholas; Hochheiser, Katharina; Carbone, Francis R; Gebhardt, Thomas

    2017-11-01

    Antigen-presenting cells (APC), such as dendritic cells (DC) and macrophages, are critical for T-cell-mediated immunity. Although it is established that memory T cells accumulate and persist in peripheral tissues after the resolution of infection, whether this is also the case for APC remains unclear. Here, we report that CCR2-dependent cells infiltrate skin during acute infection with herpes simplex virus (HSV)-1 and subsequently give rise to localized populations of DCs and macrophages. These APC are found at elevated numbers at sites of resolved infection or inflammation compared with unaffected regions of skin. Importantly, this local accumulation of APC is sustained for prolonged periods of time and has important functional consequences, as it promotes interferon-γ responses by virus-specific CD4 + T cells upon localized challenge infection with HSV-1. Thus, our results highlight how infection history determines long-term changes in immune cell composition in skin and how different types of immune cells accumulate, persist and co-operate to provide optimal immunity at this critical barrier site.

  5. MHC class I endosomal and lysosomal trafficking coincides with exogenous antigen loading in dendritic cells.

    Directory of Open Access Journals (Sweden)

    Genc Basha

    Full Text Available BACKGROUND: Cross-presentation by dendritic cells (DCs is a crucial prerequisite for effective priming of cytotoxic T-cell responses against bacterial, viral and tumor antigens; however, this antigen presentation pathway remains poorly defined. METHODOLOGY/PRINCIPAL FINDINGS: In order to develop a comprehensive understanding of this process, we tested the hypothesis that the internalization of MHC class I molecules (MHC-I from the cell surface is directly involved in cross-presentation pathway and the loading of antigenic peptides. Here we provide the first examination of the internalization of MHC-I in DCs and we demonstrate that the cytoplasmic domain of MHC-I appears to act as an addressin domain to route MHC-I to both endosomal and lysosomal compartments of DCs, where it is demonstrated that loading of peptides derived from exogenously-derived proteins occurs. Furthermore, by chasing MHC-I from the cell surface of normal and transgenic DCs expressing mutant forms of MHC-I, we observe that a tyrosine-based endocytic trafficking motif is required for the constitutive internalization of MHC-I molecules from the cell surface into early endosomes and subsequently deep into lysosomal peptide-loading compartments. Finally, our data support the concept that multiple pathways of peptide loading of cross-presented antigens may exist depending on the chemical nature and size of the antigen requiring processing. CONCLUSIONS/SIGNIFICANCE: We conclude that DCs have 'hijacked' and adapted a common vacuolar/endocytic intracellular trafficking pathway to facilitate MHC I access to the endosomal and lysosomal compartments where antigen processing and loading and antigen cross-presentation takes place.

  6. Co-delivery of PLGA encapsulated invariant NKT cell agonist with antigenic protein induce strong T cell-mediated antitumor immune responses

    NARCIS (Netherlands)

    Dolen, Y.; Kreutz, M.; Gileadi, U.; Tel, J.; Vasaturo, A.; Dinther, E.A.W. van; Hout-Kuijer, M.A. van; Cerundolo, V.; Figdor, C.G.

    2016-01-01

    Antitumor immunity can be enhanced by the coordinated release and delivery of antigens and immune-stimulating agents to antigen-presenting cells via biodegradable vaccine carriers. So far, encapsulation of TLR ligands and tumor-associated antigens augmented cytotoxic T cell (CTLs) responses. Here,

  7. Carcinoembryonic antigen and carbohydrate antigen 19-9 serum levels in non-small cell lung cancer.

    Science.gov (United States)

    Tsoukalas, Nikolaos; Kostakis, Ioannis D; Giaginis, Constantinos; Tolia, Maria; Galanopoulos, Michail; Kiakou, Maria; Aravantinou-Fatorou, Eleni; Tsapakidis, Konstantinos; Baxevanos, Panagiotis; Litos, Ioannis; Tzouda, Vasiliki; Tzovaras, Alexandros; Kyrgias, George; Tsiambas, Evangelos; Theocharis, Stamatios

    2017-01-01

    Τo investigate the potential diagnostic and prognostic role of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA 19-9) serum levels in non-small cell lung cancer (NSCLC). One hundred consecutive patients with newly diagnosed primary NSCLC were included in this study (88 men and 12 women). Blood was drawn before any kind of treatment and the collected serum was processed using chemiluminescence in order CEA and CA 19-9 levels to be measured. No significant associations between CEA or CA 19-9 levels and any tested clinical and pathological parameter were detected. Moreover, CEA levels did not seem to affect survival. On the other hand, patients with high CA 19-9 values (≥37 IU/ml) (median survival: 8 months) had a shorter overall survival than patients with low CA 19-9 values (<37 IU/ml) (median survival: 13 months) (p=0.026). However, CA 19-9 levels did not remain an independent prognostic factor in the multivariate survival analysis (p=0.114). CEA and CA 19-9 serum levels do not seem to have any diagnostic role in NSCLC. With regard to their prognostic role, CEA values do not seem to affect the prognosis in NSCLC. However, high CA 19-9 values are associated with worse prognosis.

  8. 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 immunof...

  9. 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

  10. Increased prevalence of late stage T cell activation antigen (VLA-1) in active juvenile chronic arthritis

    DEFF Research Database (Denmark)

    Ødum, Niels; Morling, Niels; Platz, P

    1987-01-01

    The presence of activated T cells as judged from the reaction with monoclonal antibodies (MoAb) against (a) a late stage T cell activation antigen (VLA-1), (b) the interleukin 2 (IL2) receptor (CD25), and (c) four different HLA class II molecules (HLA-DR, DRw52, DQ, and DP) was studied in 15 pati...

  11. 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

  12. 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...

  13. Activation of nickel-specific CD4+ T lymphocytes in the absence of professional antigen-presenting cells.

    Science.gov (United States)

    Nasorri, Francesca; Sebastiani, Silvia; Mariani, Valentina; De Pità, Ornella; Puddu, Pietro; Girolomoni, Giampiero; Cavani, Andrea

    2002-01-01

    Allergic contact dermatitis ensues from exaggerated T cell responses to haptens. Dendritic cells are required for the initiation of hapten sensitization, but they may not be necessary for disease expression. Here we investigated the antigen-presenting cell requirement of nickel-specific CD4+ lymphocytes isolated from the blood of six allergic individuals. A significant proportion (42 out of 121; 35%) of the T cell clones proliferated in vitro to nickel also in the absence of professional antigen-presenting cells, suggesting a direct T-T hapten presentation. Antigen-presenting-cell-independent T cells showed a predominant T helper 1 phenotype. Nickel recognition by these T cells was major histocompatibility complex class II restricted, not influenced by CD28 triggering, independent from their state of activation, and did not require processing. The capacity of this T cell subset to be directly stimulated by nickel was not due to unique antigen-presenting properties, as both antigen-presenting-cell-dependent and antigen-presenting-cell-independent clones displayed comparable levels of HLA-DR, CD80, and CD86, and were equally capable of presenting nickel to antigen-presenting-cell-independent clones. In contrast, neither T cell types activated antigen-presenting-cell-dependent T lymphocytes. T-T presentation induced T cell receptor downregulation, CD25, CD80, CD86, and HLA-DR upregulation, and interferon-gamma release, although to a lesser extent compared to those induced by dendritic cell-T presentation. Following T-T presentation, the clones did not undergo unresponsiveness and maintained the capacity to respond to dendritic cells pulsed with antigen. In aggregate, our data suggest that antigen-presenting-cell-independent T cell activation can effectively amplify hapten- specific immune responses.

  14. 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.

  15. MHC-based detection of antigen-specific CD8(+) T cell responses

    DEFF Research Database (Denmark)

    Hadrup, Sine Reker; Schumacher, Nana Maria Pii

    2010-01-01

    epitopes in limited biological material. These technologies are based on the joint binding of differentially labelled MHC multimers on the T cell surface, thereby providing each antigen-specific T cell population with a unique multicolour code. This strategy of 'combinatorial encoding' enables detection...... of many (at least 25) different T cell populations per sample and should be of broad value for both T cell epitope identification and immunomonitoring...

  16. 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...... of costimulatory endodomains for CAR construction to improve the effector functions of the engineered T cells. Camelid single-domain antibodies (VHHs), which are the smallest single domain antibodies, can endow great targeting ability to CAR-engineered T cells....

  17. Humoral and cell-mediated immune response to crude antigens of Dermatophilus congolensis during experimental infection of rabbits.

    Science.gov (United States)

    Makinde, A A; Wilkie, B N

    1979-01-01

    Rabbits were infected with Dermatophilus congolensis and tested for humoral immune response by indirect haemagglutination and for cell-mediated immune response to crude antigens of D. congolensis. Lymphocyte transformation and macrophage migration inhibition assays were used as in vitro correlates of cell-mediated immune response while cutaneous delayed hypersensitivity was used in vivo. Endo-antigen and whole cell antigen were found to significantly induce cell-mediated immune response. In contrast, humoral responses were found to be more significantly induced by exo-antigen. A biphasic immune response was revealed by the lymphocyte transformation test.

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

    Science.gov (United States)

    Rivera, Julie A; McGuire, Travis C

    2005-05-10

    To determine if equine monocyte-derived dendritic cells (DC) were susceptible to equine infectious anemia virus (EIAV) infection, ex vivo-generated DC were infected with virus in vitro. EIAV antigen was detected by immunofluorescence 3 days post-infection with maximum antigen being detected on day 4, whereas there was no antigen detected in DC incubated with the same amount of heat-inactivated EIAV. No cytolytic activity was observed after EIAV(WSU5) infection of DC. These monocyte-derived DC were more effective than macrophages and B cells in stimulating allogenic T lymphocytes. Both infected macrophages and DC stimulated similar levels of memory CTL responses in mixtures of CD8+ and CD4+ cells as detected with (51)Cr-release assays indicating that EIAV infection of DC did not alter antigen presentation. However, EIAV-infected DC were more effective than infected macrophages when used to stimulate memory CTL in isolated CD8+ cells. The maintenance of antigen processing and presenting function by EIAV-infected DC in vitro suggests that this function is maintained during in vivo infection.

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

    International Nuclear Information System (INIS)

    Rivera, Julie A.; McGuire, Travis C.

    2005-01-01

    To determine if equine monocyte-derived dendritic cells (DC) were susceptible to equine infectious anemia virus (EIAV) infection, ex vivo-generated DC were infected with virus in vitro. EIAV antigen was detected by immunofluorescence 3 days post-infection with maximum antigen being detected on day 4, whereas there was no antigen detected in DC incubated with the same amount of heat-inactivated EIAV. No cytolytic activity was observed after EIAV WSU5 infection of DC. These monocyte-derived DC were more effective than macrophages and B cells in stimulating allogenic T lymphocytes. Both infected macrophages and DC stimulated similar levels of memory CTL responses in mixtures of CD8+ and CD4+ cells as detected with 51 Cr-release assays indicating that EIAV infection of DC did not alter antigen presentation. However, EIAV-infected DC were more effective than infected macrophages when used to stimulate memory CTL in isolated CD8+ cells. The maintenance of antigen processing and presenting function by EIAV-infected DC in vitro suggests that this function is maintained during in vivo infection

  20. 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.

  1. An experimental protocol for the establishment of dogs with long-term cellular immune reactions to Leishmania antigens

    Directory of Open Access Journals (Sweden)

    Márcia Cristina Aquino Teixeira

    2011-03-01

    Full Text Available Domestic dogs are considered to be the main reservoirs of zoonotic visceral leishmaniasis. In this work, we evaluated a protocol to induce Leishmania infantum/Leishmania chagasi-specific cellular and humoral immune responses in dogs, which consisted of two injections of Leishmania promastigote lysate followed by a subcutaneous inoculation of viable promastigotes. The primary objective was to establish a canine experimental model to provide positive controls for testing immune responses to Leishmania in laboratory conditions. After inoculation of viable promastigotes, specific proliferative responses of peripheral blood mononuclear cells (PBMCs to either Leishmania lysate or recombinant proteins, the in vitro production of interferon-γ by antigen-stimulated PBMCs and a significant increase in circulating levels of anti-Leishmania antibodies were observed. The immunized dogs also displayed positive delayed-type hypersensitivity reactions to Leishmania crude antigens and to purified recombinant proteins. An important finding that supports the suitability of the dogs as positive controls is that they remained healthy for the entire observation period, i.e., more than seven years after infection. Following the Leishmania antigen lysate injections, the infection of dogs by the subcutaneous route appears to induce a sustained cellular immune response, leading to an asymptomatic infection. This provides a useful model for both the selection of immunogenic Leishmania antigens and for immunobiological studies on their possible immunoprotective activities.

  2. The Dominant Source of CD4+ and CD8+ T-Cell Activation in HIV Infection Is Antigenic Stimulation

    NARCIS (Netherlands)

    Cohen Stuart, J.W.T. (James Willem Theodoor); Hazebergh, M.D. (Mette); Hamann, D. (Dörte); Otto, S.A.; Borleffs, J.C.C.; Miedema, F.; Boucher, C.A.B.; Boer, R.J. de

    2000-01-01

    To distinguish between antigenic stimulation and CD4+ T-cell homeostasis as the cause of T-cell hyperactivation in HIV infection, we studied T-cell activation in 47 patients before and during highly active antiretroviral therapy (HAART). We show that expression of human leukocyte antigen

  3. Tumor Antigen Cross-Presentation and the Dendritic Cell: Where it All Begins?

    Directory of Open Access Journals (Sweden)

    Alison M. McDonnell

    2010-01-01

    Full Text Available Dendritic cells (DCs are professional antigen-presenting cells (APCs that are critical for the generation of effective cytotoxic T lymphocyte (CTL responses; however, their function and phenotype are often defective or altered in tumor-bearing hosts, which may limit their capacity to mount an effective tumor-specific CTL response. In particular, the manner in which exogenous tumor antigens are acquired, processed, and cross-presented to CD8 T cells by DCs in tumor-bearing hosts is not well understood, but may have a profound effect on antitumor immunity. In this paper, we have examined the role of DCs in the cross-presentation of tumor antigen in terms of their subset, function, migration, and location with the intention of examining the early processes that contribute to the development of an ineffective anti-tumor immune response.

  4. 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.

  5. Mucosal-Associated Invariant T Cells: New Insights into Antigen Recognition and Activation

    Directory of Open Access Journals (Sweden)

    Xingxing Xiao

    2017-11-01

    Full Text Available Mucosal-associated invariant T (MAIT cells, a novel subpopulation of innate-like T cells that express an invariant T cell receptor (TCRα chain and a diverse TCRβ chain, can recognize a distinct set of small molecules, vitamin B metabolites, derived from some bacteria, fungi but not viruses, in the context of an evolutionarily conserved major histocompatibility complex-related molecule 1 (MR1. This implies that MAIT cells may play unique and important roles in host immunity. Although viral antigens are not recognized by this limited TCR repertoire, MAIT cells are known to be activated in a TCR-independent mechanism during some viral infections, such as hepatitis C virus and influenza virus. In this article, we will review recent works in MAIT cell antigen recognition, activation and the role MAIT cells may play in the process of bacterial and viral infections and pathogenesis of non-infectious diseases.

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

    Directory of Open Access Journals (Sweden)

    Warren L Denning

    2011-02-01

    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.

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

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    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.

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

    Science.gov (United States)

    Parker, Jennifer Janell

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

  9. Equine peripheral blood mononuclear cells proliferate in response to tetanus toxoid antigen.

    Science.gov (United States)

    McKelvie, J; Little, S; Foster, A P; Cunningham, F M; Hamblin, A

    1998-01-01

    It has been reported that equine peripheral blood mononuclear cells (PBMNs) do not proliferate in response to tetanus toxoid (TT) (Frayne and Stokes 1995, Research in Veterinary Science 59, 79-81). Here we demonstrate that lymphocyte proliferation responses to TT, which are characteristic of a recall antigen, may be achieved under certain culture conditions. Given that TT vaccination is routinely applied to many horses, TT is a suitable antigen for the investigation of cellular immune responses by peripheral blood mononuclear cells in the horse.

  10. 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.

  11. Longitudinal microarray analysis of cell surface antigens on peripheral blood mononuclear cells from HIV+ individuals on highly active antiretroviral therapy

    Directory of Open Access Journals (Sweden)

    Wang Bin

    2008-03-01

    Full Text Available Abstract Background The efficacy of highly active antiretroviral therapy (HAART determined by simultaneous monitoring over 100 cell-surface antigens overtime has not been attempted. We used an antibody microarray to analyze changes in the expression of 135 different cell-surface antigens overtime on PBMC from HIV+ patients on HAART. Two groups were chosen, one (n = 6 achieved sustainable response by maintaining below detectable plasma viremia and the other (n = 6 responded intermittently. Blood samples were collected over an average of 3 years and 5–8 time points were selected for microarray assay and statistical analysis. Results Significant trends over time were observed for the expression of 7 cell surface antigens (CD2, CD3epsilon, CD5, CD95, CD36, CD27 and CD28 for combined patient groups. Between groups, expression levels of 10 cell surface antigens (CD11a, CD29, CD38, CD45RO, CD52, CD56, CD57, CD62E, CD64 and CD33 were found to be differential. Expression levels of CD9, CD11a, CD27, CD28 and CD52, CD44, CD49d, CD49e, CD11c strongly correlated with CD4+ and CD8+ T cell counts, respectively. Conclusion Our findings not only detected markers that may have potential prognostic/diagnostic values in evaluating HAART efficacy, but also showed how density of cell surface antigens could be efficiently exploited in an array-like manner in relation to HAART and HIV-infection. The antigens identified in this study should be further investigated by other methods such as flow cytometry for confirmation as biological analysis of these antigens may help further clarify their role during HAART and HIV infection.

  12. Chimeric Antigen Receptors T Cell Therapy in Solid Tumor: Challenges and Clinical Applications

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    Hamid R. Mirzaei

    2017-12-01

    Full Text Available Adoptive cellular immunotherapy (ACT employing engineered T lymphocytes expressing chimeric antigen receptors (CARs has demonstrated promising antitumor effects in advanced hematologic cancers, such as relapsed or refractory acute lymphoblastic leukemia, chronic lymphocytic leukemia, and non-Hodgkin lymphoma, supporting the translation of ACT to non-hematological malignancies. Although CAR T cell therapy has made remarkable strides in the treatment of patients with certain hematological cancers, in solid tumors success has been limited likely due to heterogeneous antigen expression, immunosuppressive networks in the tumor microenvironment limiting CAR T cell function and persistence, and suboptimal trafficking to solid tumors. Here, we outline specific approaches to overcome barriers to CAR T cell effectiveness in the context of the tumor microenvironment and offer our perspective on how expanding the use of CAR T cells in solid tumors may require modifications in CAR T cell design. We anticipate these modifications will further expand CAR T cell therapy in clinical practice.

  13. CD8α− Dendritic Cells Induce Antigen-Specific T Follicular Helper Cells Generating Efficient Humoral Immune Responses

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    Changsik Shin

    2015-06-01

    Full Text Available Recent studies on T follicular helper (Tfh cells have significantly advanced our understanding of T cell-dependent B cell responses. However, little is known about the early stage of Tfh cell commitment by dendritic cells (DCs, particularly by the conventional CD8α+ and CD8α− DC subsets. We show that CD8α− DCs localized at the interfollicular zone play a pivotal role in the induction of antigen-specific Tfh cells by upregulating the expression of Icosl and Ox40l through the non-canonical NF-κB signaling pathway. Tfh cells induced by CD8α− DCs function as true B cell helpers, resulting in significantly increased humoral immune responses against various human pathogenic antigens, including Yersinia pestis LcrV, HIV Gag, and hepatitis B surface antigen. Our findings uncover a mechanistic role of CD8α− DCs in the initiation of Tfh cell differentiation and thereby provide a rationale for investigating CD8α− DCs in enhancing antigen-specific humoral immune responses for improving vaccines and therapeutics.

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

    Science.gov (United States)

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

    1994-04-01

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

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

    International Nuclear Information System (INIS)

    Rocha, C.D.; Trombone, A.P.F.; Lorenzi, J.C.C.; Almeida, L.P.; Gembre, A.F.; Padilha, E.; Ramos, S.G.; Silva, C.L.; Coelho-Castelo, A.A.M.

    2012-01-01

    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. 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....

  18. Chimeric Antigen Receptor T-Cells for the Treatment of B-Cell Acute Lymphoblastic Leukemia

    Directory of Open Access Journals (Sweden)

    Ciprian Tomuleasa

    2018-02-01

    Full Text Available Chimeric antigen receptor (CAR T-cell technology has seen a rapid development over the last decade mostly due to the potential that these cells may have in treating malignant diseases. It is a generally accepted principle that very few therapeutic compounds deliver a clinical response without treatment-related toxicity, and studies have shown that CAR T-cells are not an exception to this rule. While large multinational drug companies are currently investigating the potential role of CAR T-cells in hematological oncology, the potential of such cellular therapies are being recognized worldwide as they are expected to expand in the patient to support the establishment of the immune memory, provide a continuous surveillance to prevent and/or treat a relapse, and keep the targeted malignant cell subpopulation in check. In this article, we present the possible advantages of using CAR T-cells in treating acute lymphoblastic leukemia, presenting the technology and the current knowledge in their preclinical and early clinical trial use. Thus, this article first presents the main present-day knowledge on the standard of care for acute lymphoblastic leukemia. Afterward, current knowledge is presented about the use of CAR T-cells in cancer immunotherapy, describing their design, the molecular constructs, and the preclinical data on murine models to properly explain the background for their clinical use. Last, but certainly not least, this article presents the use of CAR T-cells for the immunotherapy of B-cell acute lymphoblastic leukemia, describing both their potential clinical advantages and the possible side effects.

  19. Liver sinusoidal endothelial cells contribute to CD8 T cell tolerance toward circulating carcinoembryonic antigen in mice.

    Science.gov (United States)

    Höchst, Bastian; Schildberg, Frank A; Böttcher, Jan; Metzger, Christina; Huss, Sebastian; Türler, Andreas; Overhaus, Markus; Knoblich, Andreas; Schneider, Berthold; Pantelis, Dimitrios; Kurts, Christian; Kalff, Jörg C; Knolle, Percy; Diehl, Linda

    2012-11-01

    Immunity against cancer is impeded by local mechanisms promoting development of tumor-specific T cell tolerance, such as regulatory T cells, myeloid-derived suppressor cells, or immunosuppressive factors in the tumor microenvironment. The release of soluble antigens, such as carcinoembryonic antigen (CEA) from colorectal carcinoma (CRC) cells, has been investigated for diagnostic purposes, but not for its immunological consequences. Here, we address the question of whether soluble CEA influences tumor-specific immunity. Mice were injected with soluble CEA protein, and CEA-specific CD8 T cells were analyzed for their phenotype and functionality by means of restimulation ex vivo or antitumor efficacy in vivo. We furthermore characterized the CD8 T cell population in peripheral blood mononuclear cell (PBMCs) from healthy donors and colorectal carcinoma patients. In mice, circulating CEA was preferentially taken up in a mannose receptor-dependent manner and cross-presented by liver sinusoidal endothelial cells, but not dendritic cells, to CD8 T cells. Such systemically circulating CEA promoted tolerization of CEA-specific CD8 T cells in the endogenous T cell repertoire through the coinhibitory molecule B7H1. These CD8 T cells were not deleted but were rendered nonresponsive to antigen-specific stimulation and failed to control growth of CEA-expressing tumor cells. These nonresponsive CD8 T cells were phenotypically similar to central memory T cells being CD44(high) CD62L(high) CD25(neg) . We found T cells with a similar phenotype in PBMCs of healthy donors and at increased frequency also in patients with colorectal carcinoma. Our results provide evidence for the existence of an unrecognized tumor immune escape involving cross-presentation of systemically circulating tumor antigens that may influence immunotherapy of cancer. Copyright © 2012 American Association for the Study of Liver Diseases.

  20. Phenotype of Antigen Unexperienced TH Cells in the Inflamed Central Nervous System in Experimental Autoimmune Encephalomyelitis.

    Science.gov (United States)

    Franck, Sophia; Paterka, Magdalena; Birkenstock, Jerome; Zipp, Frauke; Siffrin, Volker; Witsch, Esther

    2017-06-01

    Multiple sclerosis is a chronic, disseminated inflammation of the central nervous system which is thought to be driven by autoimmune T cells. Genetic association studies in multiple sclerosis and a large number of studies in the animal model of the disease support a role for effector/memory T helper cells. However, the mechanisms underlying relapses, remission and chronic progression in multiple sclerosis or the animal model experimental autoimmune encephalomyelitis, are not clear. In particular, there is only scarce information on the role of central nervous system-invading naive T helper cells in these processes. By applying two-photon laser scanning microscopy we could show in vivo that antigen unexperienced T helper cells migrated into the deep parenchyma of the inflamed central nervous system in experimental autoimmune encephalomyelitis, independent of their antigen specificity. Using flow cytometric analyses of central nervous system-derived lymphocytes we found that only antigen-specific, formerly naive T helper cells became activated during inflammation of the central nervous system encountering their corresponding antigen.

  1. 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.......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......-specific T cells by combinatorial encoding of MHC multimers. Peptide-MHC complexes are produced by UV-mediated MHC peptide exchange and multimerized in the form of streptavidin-fluorochrome conjugates. Eight different fluorochromes are used for the generation of MHC multimers and, by a two...

  2. Regional Delivery of Chimeric Antigen Receptor (CAR T-Cells for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Praveen Sridhar

    2017-07-01

    Full Text Available Chimeric Antigen Receptor (CAR T-cells are T-cells with recombinant receptors targeted to tumor antigens. CAR-T cell therapy has emerged as a mode of immunotherapy and is now being extensively explored in hematologic cancer. In contrast, CAR-T cell use in solid tumors has been hampered by multiple obstacles. Several approaches have been taken to circumvent these obstacles, including the regional delivery of CAR-T cells. Regional CAR-T cell delivery can theoretically compensate for poor T-cell trafficking and tumor antigen specificity while avoiding systemic toxicity associated with intravenous delivery. We reviewed completed clinical trials for the treatment of glioblastoma and metastatic colorectal cancer and examined the data in these studies for safety, efficacy, and potential advantages that regional delivery may confer over systemic delivery. Our appraisal of the available literature revealed that regional delivery of CAR-T cells in both glioblastoma and hepatic colorectal metastases was generally well tolerated and efficacious in select instances. We propose that the regional delivery of CAR-T cells is an area of potential growth in the solid tumor immunotherapy, and look towards future clinical trials in head and neck cancer, mesothelioma, and peritoneal carcinomatosis as the use of this technique expands.

  3. Chimeric antigen receptor T cells: a novel therapy for solid tumors

    Directory of Open Access Journals (Sweden)

    Shengnan Yu

    2017-03-01

    Full Text Available Abstract The chimeric antigen receptor T (CAR-T cell therapy is a newly developed adoptive antitumor treatment. Theoretically, CAR-T cells can specifically localize and eliminate tumor cells by interacting with the tumor-associated antigens (TAAs expressing on tumor cell surface. Current studies demonstrated that various TAAs could act as target antigens for CAR-T cells, for instance, the type III variant epidermal growth factor receptor (EGFRvIII was considered as an ideal target for its aberrant expression on the cell surface of several tumor types. CAR-T cell therapy has achieved gratifying breakthrough in hematological malignancies and promising outcome in solid tumor as showed in various clinical trials. The third generation of CAR-T demonstrates increased antitumor cytotoxicity and persistence through modification of CAR structure. In this review, we summarized the preclinical and clinical progress of CAR-T cells targeting EGFR, human epidermal growth factor receptor 2 (HER2, and mesothelin (MSLN, as well as the challenges for CAR-T cell therapy.

  4. Regional Delivery of Chimeric Antigen Receptor (CAR) T-Cells for Cancer Therapy.

    Science.gov (United States)

    Sridhar, Praveen; Petrocca, Fabio

    2017-07-18

    Chimeric Antigen Receptor (CAR) T-cells are T-cells with recombinant receptors targeted to tumor antigens. CAR-T cell therapy has emerged as a mode of immunotherapy and is now being extensively explored in hematologic cancer. In contrast, CAR-T cell use in solid tumors has been hampered by multiple obstacles. Several approaches have been taken to circumvent these obstacles, including the regional delivery of CAR-T cells. Regional CAR-T cell delivery can theoretically compensate for poor T-cell trafficking and tumor antigen specificity while avoiding systemic toxicity associated with intravenous delivery. We reviewed completed clinical trials for the treatment of glioblastoma and metastatic colorectal cancer and examined the data in these studies for safety, efficacy, and potential advantages that regional delivery may confer over systemic delivery. Our appraisal of the available literature revealed that regional delivery of CAR-T cells in both glioblastoma and hepatic colorectal metastases was generally well tolerated and efficacious in select instances. We propose that the regional delivery of CAR-T cells is an area of potential growth in the solid tumor immunotherapy, and look towards future clinical trials in head and neck cancer, mesothelioma, and peritoneal carcinomatosis as the use of this technique expands.

  5. Antigen Exposure History Defines CD8 T Cell Dynamics and Protection during Localized Pulmonary Infections

    Science.gov (United States)

    Van Braeckel-Budimir, Natalija; Martin, Matthew D.; Hartwig, Stacey M.; Legge, Kevin L.; Badovinac, Vladimir P.; Harty, John T.

    2017-01-01

    Unlike systemic infections, little is known about the role of repeated localized infections on (re)shaping pathogen-specific memory CD8 T cell responses. Here, we used primary (1°) and secondary (2°) intranasal influenza virus infections of mice as a model to study intrinsic memory CD8 T cell properties. We show that secondary antigen exposure, relative to a single infection, generates memory CD8 T cell responses of superior magnitude in multiple tissue compartments including blood, spleen, draining lymph nodes, and lung. Unexpectedly, regardless of the significantly higher number of 2° memory CD8 T cells, similar degree of protection against pulmonary challenge was observed in both groups of mice containing 1° or 2° memory CD8 T cells. Mechanistically, using pertussis toxin-induced migration block, we showed that superior antigen-driven proliferation and ability to relocate to the site of infection allowed 1° memory CD8 T cells to accumulate in the infected lung during the first few days after challenge, compensating for the initially lower cell numbers. Taken together, the history of antigen exposures to localized pulmonary infections, through altering basic cell biology, dictates dynamic properties of protective memory CD8 T cell responses. This knowledge has important implications for a design of novel and an improvement of existing vaccines and immunization strategies. PMID:28191007

  6. 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...

  7. 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.

  8. Target-specific activation of mast cells by immunoglobulin E reactive with a renal cell carcinoma-associated antigen

    NARCIS (Netherlands)

    Luiten, R. M.; Fleuren, G. J.; Warnaar, S. O.; Litvinov, S. V.

    1996-01-01

    Immunoglobulin E (IgE) that specifically binds to antigens present on carcinoma cells may represent a useful tool to combat carcinomas. Induction of an inflammatory response at the tumor site by tumor-specific IgE may result in reduced tumor growth and tumor regression. Local mast cells may be

  9. Dichotomy of the human T cell response to Leishmania antigens. I. Th1-like response to Leishmania major promastigote antigens in individuals recovered from cutaneous leishmaniasis

    DEFF Research Database (Denmark)

    Kemp, M; Hey, A S; Kurtzhals, J A

    1994-01-01

    The T cell response to antigens from Leishmania major promastigotes was investigated in peripheral blood mononuclear cells from Sudanese individuals with a history of cutaneous leishmaniasis (CL), Sudanese individuals with positive DTH reaction in the leishmanin skin test but with no history of s...... or subclinical L. major infection is an IFN-gamma-producing Th1-like response....

  10. Dichotomy of the human T cell response to Leishmania antigens. I. Th1-like response to Leishmania major promastigote antigens in individuals recovered from cutaneous leishmaniasis

    DEFF Research Database (Denmark)

    Kemp, M; Hey, A S; Kurtzhals, J A

    1994-01-01

    The T cell response to antigens from Leishmania major promastigotes was investigated in peripheral blood mononuclear cells from Sudanese individuals with a history of cutaneous leishmaniasis (CL), Sudanese individuals with positive DTH reaction in the leishmanin skin test but with no history...

  11. Human embryonic stem cells hemangioblast express HLA-antigens

    Directory of Open Access Journals (Sweden)

    Min Wei-Ping

    2009-04-01

    Full Text Available Abstract Background It has been suggested that the initial differentiation of endothelial and hematopoietic cells during embryogenesis occurs from a common progenitor, called hemangioblast (hB. We hypothesized that these cells with dual hematopoietic/endothelial potential could be used in future regenerative medicine. Methods We used the two-step differentiation technology to generate bipotential blast cells from human embryonic stem cells (hES. This involved short differentiation in our in vitro EB system followed by differentiation in semisolid culture medium supplemented with mixture of cytokines. Results The occurrence of blast-colony-forming cells (BL-CFC during EB differentiation (day 0–6 was transient and peaked on day 3. The emergence of this event was associated with expression of mesoderm gene T, and inversely correlated with expression of endoderm gene FoxA2. Similarly, the highest BL-CFC number was associated with increase in expression of early hematopoietic/endothelial genes: CD34, CD31 and KDR. The derived colonies were composed of 30–50 blast cells on day 6 in culture. These cells had homogenous appearance in Wright-Giemsa stain, but to a different extent expressed markers of immature hematopoietic and endothelial cells (CD31, CD34, VE-cadherin, Flt-1 and mature differentiated cells (CD45, CD33, CD146. We found that some of them expressed fetal and embryonic globin genes. Interestingly, these cells expressed also HLA class I molecules, however at very low levels compared to endothelial and hematopoietic cells. The blast cells could be successfully differentiated to hematopoietic cells in a CFU assay. In these conditions, blast cells formed CFU-M colonies (63.4 ± 0.8% containing macrophages, BFU-E colonies (19.5 ± 3.5% containing nucleated red blood cells, and CFU-EM colonies (17.1 ± 2.7% composed of macrophages and nucleated erythrocytes. Cells of CFU-EM and BFU-E colonies expressed both ε – and γ- globin genes, but

  12. 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.

  13. Suppressor cell mediated regulation of delayed-type hypersensitivity to histocompatibility antigens

    NARCIS (Netherlands)

    A. Molendijk (Arie)

    1987-01-01

    textabstractDTH to allogeneic histocompatibility antigens is a T cell dependent reaction, which can be induced in immunologically competent individuals by subcutaneous (s.c.) or intravenous (i.v.) administration of alloantigens (Vander Kwast and Benner, 1978; Bianchi et al., 1984). After

  14. Identification of Theileria lestoquardi Antigens Recognized by CD8+ T Cells.

    Science.gov (United States)

    Goh, Shan; Ngugi, Daniel; Lizundia, Regina; Hostettler, Isabel; Woods, Kerry; Ballingall, Keith; MacHugh, Niall D; Morrison, W Ivan; Weir, Willie; Shiels, Brian; Werling, Dirk

    2016-01-01

    As part of an international effort to develop vaccines for Theileria lestoquardi, we undertook a limited screen to test T. lestoquardi orthologues of antigens recognised by CD8+ T lymphocyte responses against T. annulata and T. parva in cattle. Five MHC defined sheep were immunized by live T. lestoquardi infection and their CD8+ T lymphocyte responses determined. Thirteen T. lestoquardi orthologues of T. parva and T. annulata genes, previously shown to be targets of CD8+ T lymphocyte responses of immune cattle, were expressed in autologous fibroblasts and screened for T cell recognition using an IFNγ assay. Genes encoding T. lestoquardi antigens Tl8 (putative cysteine proteinase, 349 aa) or Tl9 (hypothetical secreted protein, 293 aa) were recognise by T cells from one animal that displayed a unique MHC class I genotype. Antigenic 9-mer peptide epitopes of Tl8 and Tl9 were identified through peptide scans using CD8+ T cells from the responding animal. These experiments identify the first T. lestoquardi antigens recognised by CD8+ T cell responses linked to specific MHC class I alleles.

  15. Identification of Theileria lestoquardi Antigens Recognized by CD8+ T Cells.

    Directory of Open Access Journals (Sweden)

    Shan Goh

    Full Text Available As part of an international effort to develop vaccines for Theileria lestoquardi, we undertook a limited screen to test T. lestoquardi orthologues of antigens recognised by CD8+ T lymphocyte responses against T. annulata and T. parva in cattle. Five MHC defined sheep were immunized by live T. lestoquardi infection and their CD8+ T lymphocyte responses determined. Thirteen T. lestoquardi orthologues of T. parva and T. annulata genes, previously shown to be targets of CD8+ T lymphocyte responses of immune cattle, were expressed in autologous fibroblasts and screened for T cell recognition using an IFNγ assay. Genes encoding T. lestoquardi antigens Tl8 (putative cysteine proteinase, 349 aa or Tl9 (hypothetical secreted protein, 293 aa were recognise by T cells from one animal that displayed a unique MHC class I genotype. Antigenic 9-mer peptide epitopes of Tl8 and Tl9 were identified through peptide scans using CD8+ T cells from the responding animal. These experiments identify the first T. lestoquardi antigens recognised by CD8+ T cell responses linked to specific MHC class I alleles.

  16. Activated human nasal epithelial cells modulate specific antibody response against bacterial or viral antigens.

    Directory of Open Access Journals (Sweden)

    Chiou-Yueh Yeh

    Full Text Available Nasal mucosa is an immune responsive organ evidenced by eliciting both specific local secretory IgA and systemic IgG antibody responses with intra-nasal administration of antigens. Nevertheless, the role of nasal epithelial cells in modulating such responses is unclear. Human nasal epithelial cells (hNECs obtained from sinus mucosa of patients with chronic rhinosinusitis were cultured in vitro and firstly were stimulated by Lactococcus lactis bacterium-like particles (BLPs in order to examine their role on antibody production. Secondly, both antigens of immunodominant protein IDG60 from oral Streptococcus mutans and hemagglutinin (HA from influenza virus were tested to evaluate the specific antibody response. Stimulated hNECs by BLPs exhibited a significant increase in the production of interleukin-6 (IL-6, and thymic stromal lymphopoietin (TSLP. Conditioned medium of stimulated hNECs has effects on enhancing the proliferation of CD4+ T cells together with interferon-γ and IL-5 production, increasing the costimulatory molecules on dendritic cells and augmenting the production of IDG60 specific IgA, HA specific IgG, IgA by human peripheral blood lymphocytes. Such production of antigen specific IgG and IgA is significantly counteracted in the presence of IL-6 and TSLP neutralizing antibodies. In conclusion, properly stimulated hNECs may impart immuno-modulatory effects on the antigen-specific antibody response at least through the production of IL-6 and TSLP.

  17. Genomic organization of the human T-cell antigen-receptor alpha/delta locus

    NARCIS (Netherlands)

    Satyanarayana, K.; Hata, S.; Devlin, P.; Roncarolo, M. G.; de Vries, J. E.; Spits, H.; Strominger, J. L.; Krangel, M. S.

    1988-01-01

    Two clusters of overlapping cosmid clones comprising about 100 kilobases (kb) at the human T-cell antigen-receptor alpha/delta locus were isolated from a genomic library. The structure of the germ-line V delta 1 variable gene segment was determined. V delta 1 is located 8.5 kb downstream of the V

  18. Immunization with mannosylated peptide induces poor T cell effector functions despite enhanced antigen presentation

    NARCIS (Netherlands)

    Kel, J.M.; Geus, E.D. de; Stipdonk, M.J. van; Drijfhout, J.W.; Koning, F.; Nagelkerken, L.

    2008-01-01

    In this study, we investigated the development of T cell responses in mice after administration of a mannosylated ovalbumin peptide (M-OVA323-339). Immunization with M-OVA323-339 in complete adjuvant resulted in enhanced antigen presentation in draining lymph nodes. Monitoring the fate of

  19. 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...

  20. Tolerization of an established αb-crystallin-reactive T-cell response by intravenous antigen

    NARCIS (Netherlands)

    Verbeek, R.; Mark, K. van der; Wawrousek, E.F.; Plomp, A.C.; Noort, J.M. van

    2007-01-01

    Tolerance induction to prevent activation of a naïve T-cell repertoire has been well documented in rodents and can be readily achieved by intravenous, oral or intranasal administration of antigen in the absence of adjuvants. In autoimmune diseases such as multiple sclerosis (MS) the presence of an

  1. Fungal pattern-recognition receptors and tetraspanins: partners on antigen-presenting cells.

    NARCIS (Netherlands)

    Figdor, C.G.; Spriel, A.B. van

    2010-01-01

    Fungal pattern-recognition receptors (F-PRRs), including C-type lectins, Toll-like receptors, scavenger receptors and Fc/complement receptors, are crucial for inducing anti-fungal immune responses by antigen-presenting cells. The recent identification of specific F-PRR interactions with tetraspanins

  2. Individual cathepsins degrade immune complexes internalized by antigen-presenting cells via Fcgamma receptors.

    NARCIS (Netherlands)

    Driessen, C.A.G.G.; Lennon-Dumenil, A.M.; Ploegh, H.L.

    2001-01-01

    We have analyzed the intracellular degradation of an immune complex after its FcgammaR-mediated uptake in antigen-presenting cells (APC). Mice that lack the cathepsins (Cat) S, L, B and D allowed us to assess the direct contribution of these individual proteases to the processing events observed.

  3. Proliferating cell nuclear antigen (PCNA): a key factor in DNA replication and cell cycle regulation.

    Science.gov (United States)

    Strzalka, Wojciech; Ziemienowicz, Alicja

    2011-05-01

    PCNA (proliferating cell nuclear antigen) has been found in the nuclei of yeast, plant and animal cells that undergo cell division, suggesting a function in cell cycle regulation and/or DNA replication. It subsequently became clear that PCNA also played a role in other processes involving the cell genome. This review discusses eukaryotic PCNA, with an emphasis on plant PCNA, in terms of the protein structure and its biochemical properties as well as gene structure, organization, expression and function. PCNA exerts a tripartite function by operating as (1) a sliding clamp during DNA synthesis, (2) a polymerase switch factor and (3) a recruitment factor. Most of its functions are mediated by its interactions with various proteins involved in DNA synthesis, repair and recombination as well as in regulation of the cell cycle and chromatid cohesion. Moreover, post-translational modifications of PCNA play a key role in regulation of its functions. Finally, a phylogenetic comparison of PCNA genes suggests that the multi-functionality observed in most species is a product of evolution. Most plant PCNAs exhibit features similar to those found for PCNAs of other eukaryotes. Similarities include: (1) a trimeric ring structure of the PCNA sliding clamp, (2) the involvement of PCNA in DNA replication and repair, (3) the ability to stimulate the activity of DNA polymerase δ and (4) the ability to interact with p21, a regulator of the cell cycle. However, many plant genomes seem to contain the second, probably functional, copy of the PCNA gene, in contrast to PCNA pseudogenes that are found in mammalian genomes.

  4. Epigenetic modulation of cancer-germline antigen gene expression in tumorigenic human mesenchymal stem cells: implications for cancer therapy

    DEFF Research Database (Denmark)

    Gjerstorff, Morten; Burns, Jorge S; Nielsen, Ole

    2009-01-01

    Cancer-germline antigens are promising targets for cancer immunotherapy, but whether such therapies will also eliminate the primary tumor stem cell population remains undetermined. We previously showed that long-term cultures of telomerized adult human bone marrow mesenchymal stem cells can...... spontaneously evolve into tumor-initiating, mesenchymal stem cells (hMSC-TERT20), which have characteristics of clinical sarcoma cells. In this study, we used the hMSC-TERT20 tumor stem cell model to investigate the potential of cancer-germline antigens to serve as tumor stem cell targets. We found...... of cancer-germline antigens in hMSC-TERT20 cells, while their expression levels in primary human mesenchymal stem cells remained unaffected. The expression pattern of cancer-germline antigens in tumorigenic mesenchymal stem cells and sarcomas, plus their susceptibility to enhancement by epigenetic...

  5. Cell surface antigens of radiation leukemia virus-induced BALB/c leukemias defined by syngeneic cytotoxic T lymphocytes

    International Nuclear Information System (INIS)

    Kaneko, Yukio; Oettgen, H.F.; Obata, Yuichi; Nakayama, Eiichi.

    1989-01-01

    Two cell surface antigens of mouse leukemias were defined by BALB/c cytotoxic T lymphocytes (CTL) generated against syngeneic radiation leukemia virus (RadLV)-induced leukemia, BALBRV1 or BALBRVD. Hyperimmunization of BALB/c mice with irradiated leukemias followed by in vitro sensitization of primed spleen cells resulted in the generation of CTL with high killing activity. The specificity of CTL was examined by direct cytotoxicity assays and competitive inhibition assays. A shared cell surface antigen, designated as BALBRV1 antigen, was detected by BALB/c anti-BALBRV1 CTL. BALBRV1 antigen was expressed not only on RadLV-induced BALB/c leukemias except for BALBRVD, but also on spontaneous or X-ray-induced BALB/c leukemias, chemically-induced leukemias with the H-2 d haplotype and some chemically-induced BALB/c sarcomas. In contrast, a unique cell surface antigen, designated as BALBRVD antigen, was detected by BALB/c anti-BALBRVD CTL. BALBRVD antigen was expressed only on BALBRVD, but not on thirty-nine normal lymphoid or tumor cells. These two antigens could be distinguished from those previously defined on Friend, Moloney, Rauscher or Gross murine leukemia virus (MuLV) leukemias, or MuLV-related antigens. Both cytotoxic responses were blocked by antisera against H-2K d , but not H-2D d . The relationship of BALBRV1 antigen and BALBRVD antigen to endogenous MuLV is discussed with regard to the antigenic distribution on tumor cell lines. (author)

  6. Invariant NKT cells are required for airway inflammation induced by environmental antigens

    OpenAIRE

    Wingender, Gerhard; Rogers, Paul; Batzer, Glenda; Lee, Myung Steve; Bai, Dong; Pei, Bo; Khurana, Archana; Kronenberg, Mitchell; Horner, Anthony A.

    2011-01-01

    Invariant NKT cells (iNKT cells) are a unique subset of T lymphocytes that rapidly carry out effector functions. In this study, we report that a majority of sterile house dust extracts (HDEs) tested contained antigens capable of activating mouse and human iNKT cells. HDEs had adjuvant-like properties in an ovalbumin (OVA)-induced asthma model, which were dependent on V?14i NKT cells, as vaccinated animals deficient for iNKT cells displayed significantly attenuated immune responses and airway ...

  7. Interferon-β Suppresses Murine Th1 Cell Function in the Absence of Antigen-Presenting Cells

    Science.gov (United States)

    Boivin, Nicolas; Baillargeon, Joanie; Doss, Prenitha Mercy Ignatius Arokia; Roy, Andrée-Pascale; Rangachari, Manu

    2015-01-01

    Interferon (IFN)-β is a front-line therapy for the treatment of the relapsing-remitting form of multiple sclerosis. However, its immunosuppressive mechanism of function remains incompletely understood. While it has been proposed that IFN-β suppresses the function of inflammatory myelin antigen-reactive T cells by promoting the release of immunomodulatory cytokines such as IL-27 from antigen-presenting cells (APCs), its direct effects on inflammatory CD4+ Th1 cells are less clear. Here, we establish that IFN-β inhibits mouse IFN-γ+ Th1 cell function in the absence of APCs. CD4+ T cells express the type I interferon receptor, and IFN-β can suppress Th1 cell proliferation under APC-free stimulation conditions. IFN-β-treated myelin antigen-specific Th1 cells are impaired in their ability to induce severe experimental autoimmune encephalomyelitis (EAE) upon transfer to lymphocyte-deficient Rag1-/- mice. Polarized Th1 cells downregulate IFN-γ and IL-2, and upregulate the negative regulatory receptor Tim-3, when treated with IFN-β in the absence of APCs. Further, IFN-β treatment of Th1 cells upregulates phosphorylation of Stat1, and downregulates phosphorylation of Stat4. Our data indicate that IFN-γ-producing Th1 cells are directly responsive to IFN-β and point to a novel mechanism of IFN-β-mediated T cell suppression that is independent of APC-derived signals. PMID:25885435

  8. Estradiol-induced vaginal mucus inhibits antigen penetration and CD8(+) T cell priming in response to intravaginal immunization.

    Science.gov (United States)

    Seavey, Matthew M; Mosmann, Tim R

    2009-04-14

    Although vaginal immunization has been explored as a strategy to induce mucosal immunity in the female reproductive tract, this site displays unique immunological features that probably evolved to inhibit anti-paternal T cell responses after insemination to allow successful pregnancy. We previously demonstrated that estradiol, which induces an estrus-like state, prevented CD8(+) T cell priming during intravaginal immunization of mice. We now show that estradiol prevented antigen loading of vaginal antigen presenting cells (APCs) after intravaginal immunization. Histological examination confirmed that estradiol prevented penetration of peptide antigen into the vaginal wall. Removal of the estradiol-induced mucus barrier by mucinase partially restored antigen loading of vaginal APC and CD8(+) T cell proliferation in vivo. The estradiol-induced mucus barrier may thus prevent exposure to antigens delivered intravaginally, supplementing additional estradiol-dependent mechanism(s) that inhibit CD8(+) T cell priming after insemination or vaginal vaccination.

  9. Estradiol-induced vaginal mucus inhibits antigen penetration and CD8+ T cell priming in response to intravaginal immunization

    Science.gov (United States)

    Seavey, Matthew M.; Mosmann, Tim R.

    2010-01-01

    Although vaginal immunization has been explored as a strategy to induce mucosal immunity in the female reproductive tract, this site displays unique immunological features that probably evolved to inhibit anti-paternal T cell responses after insemination to allow successful pregnancy. We previously demonstrated that estradiol, which induces an estrus-like state, prevented CD8+ T cell priming during intravaginal immunization of mice. We now show that estradiol prevented antigen loading of vaginal antigen presenting cells (APC) after intravaginal immunization. Histological examination confirmed that estradiol prevented penetration of peptide antigen into the vaginal wall. Removal of the estradiol-induced mucus barrier by mucinase partially restored antigen loading of vaginal APC and CD8+ T cell proliferation in vivo. The estradiol-induced mucus barrier may thus prevent exposure to antigens delivered intravaginally, supplementing additional estradiol-dependent mechanism(s) that inhibit CD8+ T cell priming after insemination or vaginal vaccination. PMID:19428849

  10. Butyrate and propionate inhibit antigen-specific CD8+ T cell activation by suppressing IL-12 production by antigen-presenting cells

    DEFF Research Database (Denmark)

    Nastasi, Claudia; Fredholm, Simon; Willerslev-Olsen, Andreas

    2017-01-01

    Short chain fatty acids (SCFAs), such as acetate, butyrate and propionate, are products of microbial macronutrients fermentation that distribute systemically and are believed to modulate host immune responses. Recent data have indicated that certain SCFAs, such as butyrate and propionate, directly...... modulate human dendritic cell (DC) function. Given the role of DCs in initiating and shaping the adaptive immune response, we now explore how SCFAs affect the activation of antigen-specific CD8+ T cells stimulated with autologous, MART1 peptide-pulsed DC. We show that butyrate reduces the frequency...... of peptide-specific CD8+ T cells and, together with propionate, inhibit the activity of those cells. On the contrary, acetate does not affect them. Importantly, butyrate and propionate inhibit the production of IL-12 and IL-23 in the DCs and exogenous IL-12 fully restores the activation of the MART-1...

  11. Complement-dependent transport of antigen into B cell follicles

    DEFF Research Database (Denmark)

    Gonzalez, Santiago F.; Lukacs-Kornek, Veronika; Kuligowski, Michael P.

    2010-01-01

    an additional novel pathway in which complement C3 and its receptors enhance humoral immunity through delivery of Ag to the B cell compartment. In this review, we discuss this pathway and highlight several novel exceptions recently found with a model influenza vaccine, such as mannose-binding lectin...... opsonization of influenza and uptake by macrophages, and the capture of virus by dendritic cells residing in the medullary compartment of peripheral lymph nodes....

  12. Exosomes: novel effectors of human platelet lysate activity

    Directory of Open Access Journals (Sweden)

    E Torreggiani

    2014-09-01

    Full Text Available Despite the popularity of platelet-rich plasma (PRP and platelet lysate (PL in orthopaedic practice, the mechanism of action and the effectiveness of these therapeutic tools are still controversial. So far, the activity of PRP and PL has been associated with different growth factors (GF released during platelet degranulation. This study, for the first time, identifies exosomes, nanosized vesicles released in the extracellular compartment by a number of elements, including platelets, as one of the effectors of PL activity. Exosomes were isolated from human PL by differential ultracentrifugation, and analysed by electron microscopy and Western blotting. Bone marrow stromal cells (MSC treated with three different exosome concentrations (0.6 μg, 5 μg and 50 μg showed a significant, dose-dependent increase in cell proliferation and migration compared to the control. In addition, osteogenic differentiation assays demonstrated that exosome concentration differently affected the ability of MSC to deposit mineralised matrix. Finally, the analysis of exosome protein content revealed a higher amount of basic fibroblast growth factor (bFGF, vascular endothelial growth factor (VEGF, platelet-derived growth factor (PDGF-BB and transforming growth factor beta 1 (TGF-β1 as compared to PL. In regards to RNA content, an enrichment of small RNAs in exosomes as compared to donor platelets has been found. These results suggest that exosomes consistently contribute to PL activity and could represent an advantageous nanodelivery system for cell-free regeneration therapies.

  13. Inhibitory activities of microalgal extracts against Epstein-Barr Virus (EBV antigen expression in lymphoblastoid cells

    Directory of Open Access Journals (Sweden)

    Koh Yih Yih

    2014-01-01

    Full Text Available The inhibitory activities of microalgal extracts against the expression of three EBV antigens, latent membrane protein (LMP1, Epstein-Barr nuclear antigen (EBNA1 and Z Epstein-Barr reactivation activator (ZEBRA were assessed by immunocytochemistry. The observation that the methanol extracts and their fractions from Ankistrodesmus convolutus, Synechococcus elongatus and Spirulina platensis exhibited inhibitory activity against EBV proteins in three Burkitt’s lymphoma cell lines at concentrations as low as 20 μg/ml suggests that microalgae could be a potential source of antiviral compounds against EBV.

  14. Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

    International Nuclear Information System (INIS)

    Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

    1987-01-01

    The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of 3 H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes

  15. Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

    Energy Technology Data Exchange (ETDEWEB)

    Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

    1987-11-01

    The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of /sup 3/H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes.

  16. Brain antigens in functionally distinct antigen-presenting cell populations in cervical lymph nodes in MS and EAE

    NARCIS (Netherlands)

    M. van Zwam (Marloes); R. Huizinga (Ruth); M.J. Melief (Marie-José); A.F. Wierenga-Wolf (Annet); M. van Meurs (Marjan); J.S. Voerman (Jane); K.P.H. Biber (Knut); H.W.G.M. Boddeke (Hendrikus); U.E. Höpken (Uta); C. Meisel (Christian); I. Bechmann (Ingo); R.Q. Hintzen (Rogier); B.A. 't Hart (Bert); S. Amor (Sandra); J.D. Laman (Jon); L.A. Boven (Leonie)

    2009-01-01

    textabstractDrainage of central nervous system (CNS) antigens to the brain-draining cervical lymph nodes (CLN) is likely crucial in the initiation and control of autoimmune responses during multiple sclerosis (MS). We demonstrate neuronal antigens within CLN of MS patients. In monkeys and mice with

  17. Antigen-specific IgA B memory cell responses to Shigella antigens elicited in volunteers immunized with live attenuated Shigella flexneri 2a oral vaccine candidates

    OpenAIRE

    Simon, J. K.; Maciel, M.; Weld, E.D.; Wahid, R.; Pasetti, M.F.; Picking, W.L.; Kotloff, K. L.; Levine, M. M.; Sztein, M. B.

    2011-01-01

    We studied the induction of antigen-specific IgA memory B cells (BM) in volunteers who received live attenuated Shigella flexneri 2a vaccines. Subjects ingested a single oral dose of 107, 108 or 109 CFU of S. flexneri 2a with deletions in guaBA (CVD 1204) or in guaBA, set and sen (CVD 1208). Antigen-specific serum and stool antibody responses to LPS and Ipa B were measured on days 0, 7, 14, 28 and 42. IgA BM cells specific to LPS, Ipa B and total IgA were assessed on days 0 and 28. We show th...

  18. IL-4Rα-associated antigen processing by B cells promotes immunity in Nippostrongylus brasiliensis infection.

    Directory of Open Access Journals (Sweden)

    William G C Horsnell

    2013-10-01

    Full Text Available In this study, B cell function in protective T(H2 immunity against N. brasiliensis infection was investigated. Protection against secondary infection depended on IL-4Rα and IL-13; but not IL-4. Protection did not associate with parasite specific antibody responses. Re-infection of B cell-specific IL-4Rα⁻/⁻ mice resulted in increased worm burdens compared to control mice, despite their equivalent capacity to control primary infection. Impaired protection correlated with reduced lymphocyte IL-13 production and B cell MHC class II and CD86 surface expression. Adoptive transfer of in vivo N. brasiliensis primed IL-4Rα expressing B cells into naïve BALB/c mice, but not IL-4Rα or IL-13 deficient B cells, conferred protection against primary N. brasiliensis infection. This protection required MHC class II compatibility on B cells suggesting cognate interactions by B cells with CD4⁺ T cells were important to co-ordinate immunity. Furthermore, the rapid nature of these protective effects by B cells suggested non-BCR mediated mechanisms, such as via Toll Like Receptors, was involved, and this was supported by transfer experiments using antigen pulsed Myd88⁻/⁻ B cells. These data suggest TLR dependent antigen processing by IL-4Rα-responsive B cells producing IL-13 contribute significantly to CD4⁺ T cell-mediated protective immunity against N. brasiliensis infection.

  19. IL-4Rα-Associated Antigen Processing by B Cells Promotes Immunity in Nippostrongylus brasiliensis Infection

    Science.gov (United States)

    Hoving, Jennifer C.; Nieuwenhuizen, Natalie; McSorley, Henry J.; Ndlovu, Hlumani; Bobat, Saeeda; Kimberg, Matti; Kirstein, Frank; Cutler, Anthony J.; DeWals, Benjamin; Cunningham, Adam F.; Brombacher, Frank

    2013-01-01

    In this study, B cell function in protective TH2 immunity against N. brasiliensis infection was investigated. Protection against secondary infection depended on IL-4Rα and IL-13; but not IL-4. Protection did not associate with parasite specific antibody responses. Re-infection of B cell-specific IL-4Rα−/− mice resulted in increased worm burdens compared to control mice, despite their equivalent capacity to control primary infection. Impaired protection correlated with reduced lymphocyte IL-13 production and B cell MHC class II and CD86 surface expression. Adoptive transfer of in vivo N. brasiliensis primed IL-4Rα expressing B cells into naïve BALB/c mice, but not IL-4Rα or IL-13 deficient B cells, conferred protection against primary N. brasiliensis infection. This protection required MHC class II compatibility on B cells suggesting cognate interactions by B cells with CD4+ T cells were important to co-ordinate immunity. Furthermore, the rapid nature of these protective effects by B cells suggested non-BCR mediated mechanisms, such as via Toll Like Receptors, was involved, and this was supported by transfer experiments using antigen pulsed Myd88−/− B cells. These data suggest TLR dependent antigen processing by IL-4Rα-responsive B cells producing IL-13 contribute significantly to CD4+ T cell-mediated protective immunity against N. brasiliensis infection. PMID:24204255

  20. Immunotherapy of hormone-refractory prostate cancer with antigen-loaded dendritic cells.

    Science.gov (United States)

    Small, E J; Fratesi, P; Reese, D M; Strang, G; Laus, R; Peshwa, M V; Valone, F H

    2000-12-01

    Provenge (Dendreon Corp, Seattle, WA) is an immunotherapy product consisting of autologous dendritic cells loaded ex vivo with a recombinant fusion protein consisting of prostatic acid phosphatase (PAP) linked to granulocyte-macrophage colony-stimulating factor. Sequential phase I and phase II trials were performed to determine the safety and efficacy of Provenge and to assess its capacity to break immune tolerance to the normal tissue antigen PAP. All patients had hormone-refractory prostate cancer. Dendritic-cell precursors were harvested by leukapheresis in weeks 0, 4, 8, and 24, loaded ex vivo with antigen for 2 days, and then infused intravenously over 30 minutes. Phase I patients received increasing doses of Provenge, and phase II patients received all the Provenge that could be prepared from a leukapheresis product. Patients tolerated treatment well. Fever, the most common adverse event, occurred after 15 infusions (14.7%). All patients developed immune responses to the recombinant fusion protein used to prepare Provenge, and 38% developed immune responses to PAP. Three patients had a more than 50% decline in prostate-specific antigen (PSA) level, and another three patients had 25% to 49% decreases in PSA. The time to disease progression correlated with development of an immune response to PAP and with the dose of dendritic cells received. Provenge is a novel immunotherapy agent that is safe and breaks tolerance to the tissue antigen PAP. Preliminary evidence for clinical efficacy warrants further exploration.

  1. TANTIGEN: a comprehensive database of tumor T cell antigens

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn; Tongchusak, Songsak; Lin, Honghuang

    2017-01-01

    than 1000 tumor peptides from 368 different proteins, and implemented a web-accessible infrastructure for storing and accessing these experimental results. All peptides in TANTIGEN are labeled as one of the four categories: (1) peptides measured in vitro to bind the HLA, but not reported to elicit...... either in vivo or in vitro T cell response, (2) peptides found to bind the HLA and to elicit an in vitro T cell response, (3) peptides shown to elicit in vivo tumor rejection, and (4) peptides processed and naturally presented as defined by physical detection. In addition to T cell response, we also...... annotate peptides that are naturally processed HLA binders, e.g., peptides eluted from HLA in mass spectrometry studies. TANTIGEN provides a rich data resource for tumor-associated epitope and neoepitope discovery studies and is freely available at (mirror)....

  2. A DEFICIENCY OF ANTIGEN-PRESENTING CELLS IN PATIENTS WITH PULMONARY TUBERCULOSIS

    Directory of Open Access Journals (Sweden)

    L. V. Sakhno

    2009-01-01

    Full Text Available Abstract. The phenotype and functional properties of antigen-presenting cells (APCs: blood monocytes and in vitro generated macrophages/dendritic cells were investigated in patients with pulmonary tuberculosis (TB, n = 192 with different levels of proliferative response to M. tuberculosis antigens (PPD-responsive vs PPD - anergic patients, n = 118 and 74, respectively. A functional deficiency of all 3 types of APCs was revealed in patients with TB. I.e., a monocyte disfunction was displayed by low CD86 and HLA-DR expression, 2-fold increase of CD14+CD16+ subset, high level of FasL+ and IL-10+ cells, and enhanced IL-10 and IL-6 production upon LPS-stimulation. The in vitro generated macrophages from blood monocytes challenged with GM-CSF, were characterized by shifted Th1/Th2 balance (down-regulated production of IFNγ and IL-18 combined with up-regulation of IL-6 and IL-10, and reduced allostimulatory activity in mixed lymphocyte culture. The dendritic cells were characterized by decrease of mature, activated CD25+ cells, low level of IFNγ production in conjunction with enhanced capacity to produce IL - 10 and IL-6, and profound reduction of functional (allostimulatory activity. The APC disfunction of were most prominent in PPD-anergic patients. A possible role of APC disfunctions in disturbed antigen-specific T-cell response to M. tuberculosis is discussed.

  3. Design and development of therapies using chimeric antigen receptor-expressing T cells.

    Science.gov (United States)

    Dotti, Gianpietro; Gottschalk, Stephen; Savoldo, Barbara; Brenner, Malcolm K

    2014-01-01

    Investigators developed chimeric antigen receptors (CARs) for expression on T cells more than 25 years ago. When the CAR is derived from an antibody, the resultant cell should combine the desirable targeting features of an antibody (e.g. lack of requirement for major histocompatibility complex recognition, ability to recognize non-protein antigens) with the persistence, trafficking, and effector functions of a T cell. This article describes how the past two decades have seen a crescendo of research which has now begun to translate these potential benefits into effective treatments for patients with cancer. We describe the basic design of CARs, describe how antigenic targets are selected, and the initial clinical experience with CAR-T cells. Our review then describes our own and other investigators' work aimed at improving the function of CARs and reviews the clinical studies in hematological and solid malignancies that are beginning to exploit these approaches. Finally, we show the value of adding additional engineering features to CAR-T cells, irrespective of their target, to render them better suited to function in the tumor environment, and discuss how the safety of these heavily modified cells may be maintained. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Phenotype and functional evaluation of ex vivo generated antigen-specific immune effector cells with potential for therapeutic applications

    Directory of Open Access Journals (Sweden)

    Wang Yichen

    2009-08-01

    Full Text Available Abstract Ex vivo activation and expansion of lymphocytes for adoptive cell therapy has demonstrated great success. To improve safety and therapeutic efficacy, increased antigen specificity and reduced non-specific response of the ex vivo generated immune cells are necessary. Here, using a complete protein-spanning pool of pentadecapeptides of the latent membrane protein 2A (LMP2A of Epstein-Barr virus (EBV, a weak viral antigen which is associated with EBV lymphoproliferative diseases, we investigated the phenotype and function of immune effector cells generated based on IFN-γ or CD137 activation marker selection and dendritic cell (DC activation. These ex vivo prepared immune cells exhibited a donor- and antigen-dependent T cell response; the IFN-γ-selected immune cells displayed a donor-related CD4- or CD8-dominant T cell phenotype; however, the CD137-enriched cells showed an increased ratio of CD4 T cells. Importantly, the pentadecapeptide antigens accessed both class II and class I MHC antigen processing machineries and effectively activated EBV-specific CD4 and CD8 T cells. Phenotype and kinetic analyses revealed that the IFN-γ and the CD137 selections enriched more central memory T (Tcm cells than did the DC-activation approach, and after expansion, the IFN-γ-selected effector cells showed the highest level of antigen-specificity and effector activities. While all three approaches generated immune cells with comparable antigen-specific activities, the IFN-γ selection followed by ex vivo expansion produced high quality and quantity of antigen-specific effector cells. Our studies presented the optimal approach for generating therapeutic immune cells with potential for emergency and routine clinical applications.

  5. Prolonged antigen presentation is required for optimal CD8+ T cell responses against malaria liver stage parasites.

    Directory of Open Access Journals (Sweden)

    Ian A Cockburn

    2010-05-01

    Full Text Available Immunization with irradiated sporozoites is currently the most effective vaccination strategy against liver stages of malaria parasites, yet the mechanisms underpinning the success of this approach are unknown. Here we show that the complete development of protective CD8+ T cell responses requires prolonged antigen presentation. Using TCR transgenic cells specific for the malaria circumsporozoite protein, a leading vaccine candidate, we found that sporozoite antigen persists for over 8 weeks after immunization--a remarkable finding since irradiated sporozoites are incapable of replication and do not differentiate beyond early liver stages. Persisting antigen was detected in lymphoid organs and depends on the presence of CD11c+ cells. Prolonged antigen presentation enhanced the magnitude of the CD8+ T cell response in a number of ways. Firstly, reducing the time primed CD8+ T cells were exposed to antigen in vivo severely reduced the final size of the developing memory population. Secondly, fully developed memory cells expanded in previously immunized mice but not when transferred to naïve animals. Finally, persisting antigen was able to prime naïve cells, including recent thymic emigrants, to become functional effector cells capable of eliminating parasites in the liver. Together these data show that the optimal development of protective CD8+ T cell immunity against malaria liver stages is dependent upon the prolonged presentation of sporozoite-derived antigen.

  6. THE ANTIGEN-SPECIFIC CELL IN VITRO TESTS FOR POST-VACCINATION ANTIPLAGUE IMMUNITY FORMATION

    Directory of Open Access Journals (Sweden)

    A. N. Kulichenko

    2017-01-01

    Full Text Available The possibility of post-vaccination anti-plague immunity evaluation was researched using antigen-stimulated cells tests in vitro and cytometry analysis. The object of study — the blood samples of 17 people immunised by the live plague vaccine (Yersinia pestis EV epicutaneously. Blood taking was carried out before vaccination and after immunisation on 7 and on 21 days, in 3 and in 6 months. Intensity antigen reactivity of lymphocytes was detected by cell tests in vitro, analysing markers of early (CD45+CD3+CD25+ and late (CD45+CD3+HLA-DR+ lymphocyte activation using flow cytometry. The complex of water-soluble Y. pestis antigens and allergen — pestin PP was tested as antigen. The high stimulating potential was defined of the water-soluble antigens Y. pestis complex. It is shown that coefficient of stimulation of relative level T- lymphocytes which express receptors for IL-2 was positive for all observation times after immunisation. The coefficient of stimulation had maximum values at 21 days (56.37% and at 3 (47.41% months. In identifying HLADR-positive lymphocytes before vaccination, the negative coefficient of stimulation was indicated on 7 and 21 days and the positive coefficient of stimulation was indicated at 3 and at 6 months. Analysis of intensity expression of early and late lymphocyte activation markers dynamics showed the possibility and prospect of application of cellular in vitro tests for the laboratory evaluation of specific reactivity of cellular immunity in both the early (7 days and late (6 months periods after vaccination. The results can be the basis for developing a new algorithm for assessment of immunological effectiveness of vaccination people against plague. It is the algorithm based on the identification of lymphocyte activation markers by antigen stimulation in conditions in vitro.

  7. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Approach to discover T- and B-cell antigens of intracellular pathogens applied to the design of Chlamydia trachomatis vaccines

    Science.gov (United States)

    Finco, Oretta; Frigimelica, Elisabetta; Buricchi, Francesca; Petracca, Roberto; Galli, Giuliano; Faenzi, Elisa; Meoni, Eva; Bonci, Alessandra; Agnusdei, Mauro; Nardelli, Filomena; Bartolini, Erika; Scarselli, Maria; Caproni, Elena; Laera, Donatello; Zedda, Luisanna; Skibinski, David; Giovinazzi, Serena; Bastone, Riccardo; Ianni, Elvira; Cevenini, Roberto; Grandi, Guido; Grifantini, Renata

    2011-01-01

    Natural immunity against obligate and/or facultative intracellular pathogens is usually mediated by both humoral and cellular immunity. The identification of those antigens stimulating both arms of the immune system is instrumental for vaccine discovery. Although high-throughput technologies have been applied for the discovery of antibody-inducing antigens, few examples of their application for T-cell antigens have been reported. We describe how the compilation of the immunome, here defined as the pool of immunogenic antigens inducing T- and B-cell responses in vivo, can lead to vaccine candidates against Chlamydia trachomatis. We selected 120 C. trachomatis proteins and assessed their immunogenicity using two parallel high-throughput approaches. Protein arrays were generated and screened with sera from C. trachomatis-infected patients to identify antibody-inducing antigens. Splenocytes from C. trachomatis-infected mice were stimulated with 79 proteins, and the frequency of antigen-specific CD4+/IFN-γ+ T cells was analyzed by flow cytometry. We identified 21 antibody-inducing antigens, 16 CD4+/IFN-γ+–inducing antigens, and five antigens eliciting both types of responses. Assessment of their protective activity in a mouse model of Chlamydia muridarum lung infection led to the identification of seven antigens conferring partial protection when administered with LTK63/CpG adjuvant. Protection was largely the result of cellular immunity as assessed by CD4+ T-cell depletion. The seven antigens provided robust additive protection when combined in four-antigen combinations. This study paves the way for the development of an effective anti-Chlamydia vaccine and provides a general approach for the discovery of vaccines against other intracellular pathogens. PMID:21628568

  10. Human leukocyte antigen-E mismatch is associated with better hematopoietic stem cell transplantation outcome in acute leukemia patients.

    Science.gov (United States)

    Tsamadou, Chrysanthi; Fürst, Daniel; Vucinic, Vladan; Bunjes, Donald; Neuchel, Christine; Mytilineos, Daphne; Gramatzki, Martin; Arnold, Renate; Wagner, Eva Maria; Einsele, Hermann; Müller, Carlheinz; Schrezenmeier, Hubert; Mytilineos, Joannis

    2017-11-01

    The immunomodulatory role of human leukocyte antigen (HLA)-E in hematopoietic stem cell transplantation (HSCT) has not been extensively investigated. To this end, we genotyped 509 10/10 HLA unrelated transplant pairs for HLA-E , in order to study the effect of HLA-E as a natural killer (NK)-alloreactivity mediator on HSCT outcome in an acute leukemia (AL) setting. Overall survival (OS), disease free survival (DFS), relapse incidence (RI) and non-relapse mortality (NRM) were set as endpoints. Analysis of our data revealed a significant correlation between HLA-E mismatch and improved HSCT outcome, as shown by both univariate (53% vs 38%, P =0.002, 5-year OS) and multivariate (hazard ratio (HR)=0.63, confidence interval (CI) 95%=0.48-0.83, P =0.001) analyses. Further subgroup analysis demonstrated that the positive effect of HLA-E mismatch was significant and pronounced in advanced disease patients (n=120) (5-year OS: 50% vs 18%, P =0.005; HR=0.40, CI 95%=0.22-0.72, P =0.002; results from univariate and multivariate analyses, respectively). The study herein is the first to report an association between HLA-E incompatibility and improved post-transplant prognosis in AL patients who have undergone matched unrelated HSCT. Combined NK and T cell HLA-E-mediated mechanisms may account for the better outcomes observed. Notwithstanding the necessity for in vitro and confirmational studies, our findings highlight the clinical relevance of HLA-E matching and strongly support prospective HLA-E screening upon donor selection for matched AL unrelated HSCTs. Copyright© Ferrata Storti Foundation.

  11. Proliferating cell nuclear antigen immunostaining in breast carcinoma and its relationship to clinical and pathological variables.

    Science.gov (United States)

    Agarwal, S; Jain, R; Rusia, U; Gupta, R L

    1997-01-01

    Tumour proliferative activity of 74 breast lesions was assessed by determining mitotic index and immunostaining for proliferative cell nuclear antigen using Peroxidase antiperoxidase method. The indices were correlated with histomorphology and clinical stage of the disease. Positively stained nuclei and mitotic figures were counted per 1000 cells to calculate Proliferating Cell Nuclear Antigen (PCNA) and mitotic index respectively. Sixty four cases stained positive for PCNA. The index ranged between 0 to 98. PCNA index was significantly low in benign lesions as compared to malignant lesions (p < 0.0002). There was a linear correlation between the mitotic index and PCNA index. PCNA index also showed significant correlation with tumour size and histologic grade; however, it had no correlation with axillary lymph node status.

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

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  13. Carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) in cancer progression and metastasis.

    Science.gov (United States)

    Beauchemin, Nicole; Arabzadeh, Azadeh

    2013-12-01

    The discovery of the carcinoembryonic antigen (CEA) as a tumor marker for colorectal cancer some 50 years ago became the first step in the identification of a much larger family of 12 carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) with surprisingly diverse functions in cell adhesion, in intracellular and intercellular signaling, and during complex biological processes such as cancer progression, inflammation, angiogenesis, and metastasis. The development of proper molecular and biochemical tools and mouse models has enabled bidirectional translation of the CEACAM network biology. Indeed, CEACAM1, CEACAM5, and CEACAM6 are now considered valid clinical biomarkers and promising therapeutic targets in melanoma, lung, colorectal, and pancreatic cancers. These fascinating proteins illustrate how a better understanding of the CEACAM family of cell adhesion molecules reveals their functional link to the underlying disease and lead to new monitoring and targeting opportunities.

  14. CD1a presentation of endogenous antigens by group 2 innate lymphoid cells.

    Science.gov (United States)

    Hardman, Clare S; Chen, Yi-Ling; Salimi, Maryam; Jarrett, Rachael; Johnson, David; Järvinen, Valtteri J; Owens, Raymond J; Repapi, Emmanouela; Cousins, David J; Barlow, Jillian L; McKenzie, Andrew N J; Ogg, Graham

    2017-12-22

    Group 2 innate lymphoid cells (ILC2) are effectors of barrier immunity, with roles in infection, wound healing, and allergy. A proportion of ILC2 express MHCII (major histocompatibility complex II) and are capable of presenting peptide antigens to T cells and amplifying the subsequent adaptive immune response. Recent studies have highlighted the importance of CD1a-reactive T cells in allergy and infection, activated by the presentation of endogenous neolipid antigens and bacterial components. Using a human skin challenge model, we unexpectedly show that human skin-derived ILC2 can express CD1a and are capable of presenting endogenous antigens to T cells. CD1a expression is up-regulated by TSLP (thymic stromal lymphopoietin) at levels observed in the skin of patients with atopic dermatitis, and the response is dependent on PLA2G4A. Furthermore, this pathway is used to sense Staphylococcus aureus by promoting Toll-like receptor-dependent CD1a-reactive T cell responses to endogenous ligands. These findings define a previously unrecognized role for ILC2 in lipid surveillance and identify shared pathways of CD1a- and PLA2G4A-dependent ILC2 inflammation amenable to therapeutic intervention. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  15. Osteopontin promotes dendritic cell maturation and function in response to HBV antigens

    Directory of Open Access Journals (Sweden)

    Cui GY

    2015-06-01

    Full Text Available Guangying Cui,1,2 Jianing Chen,1,2 Jianqin He,1,2 Chong Lu,1,2 Yingfeng Wei,1,2 Lin Wang,1,2 Xuejun Xu,3 Lanjuan Li,1,2 Toshimitsu Uede,4 Hongyan Diao1,2 1State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 2Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, 3Department of Oral Orthodontics, Affiliated Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, People’s Republic of China; 4Molecular Immunology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan Purpose: Dendritic cells (DCs play critical roles in promoting innate and adaptive immunity in microbial infection. Functional impairment of DCs may mediate the suppression of viral-specific T-cell immune response in chronic hepatitis B (CHB patients. Osteopontin (OPN is involved in several liver diseases and infectious diseases. However, whether OPN affects DC function in hepatitis B virus (HBV infection is unknown.Methods: Twenty CHB patients and 20 healthy volunteers were recruited. OPN secreted by DCs was compared. Peripheral blood mononuclear cells cultured with OPN antibody were examined to study the costimulatory molecular expression and interleukin (IL-12 production of DCs after HBV antigenic stimulation. OPN-deficient mice were used to investigate the influence of OPN on DC maturation and function after HBV antigenic stimulation in vitro and in vivo. Exogenous OPN was administrated to further verify the functioning of DCs from CHB patients upon HBV antigenic stimulation.Results: We found that OPN production of DCs from CHB patients was significantly lower than those from healthy volunteers. The absence of OPN impaired IL-12 production and costimulatory molecular expression of DCs upon stimulation with HBV antigens. Defective DC function led to reduced activation of Th1 response to

  16. Archaeosome Adjuvant Overcomes Tolerance to Tumor-Associated Melanoma Antigens Inducing Protective CD8+ T Cell Responses

    Directory of Open Access Journals (Sweden)

    Lakshmi Krishnan

    2010-01-01

    Full Text Available Vesicles comprised of the ether glycerolipids of the archaeon Methanobrevibacter smithii (archaeosomes are potent adjuvants for evoking CD8+ T cell responses. We therefore explored the ability of archaeosomes to overcome immunologic tolerance to self-antigens. Priming and boosting of mice with archaeosome-antigen evoked comparable CD8+ T cell response and tumor protection to an alternate boosting strategy utilizing live bacterial vectors for antigen delivery. Vaccination with melanoma antigenic peptides TRP181-189 and Gp10025-33 delivered in archaeosomes resulted in IFN-γ producing antigen-specific CD8+ T cells with strong cytolytic capability and protection against subcutaneous B16 melanoma. Targeting responses against multiple antigens afforded prolonged median survival against melanoma challenge. Entrapment of multiple peptides within the same vesicle or admixed formulations were both effective at evoking CD8+ T cells against each antigen. Melanoma-antigen archaeosome formulations also afforded therapeutic protection against established B16 tumors when combined with depletion of T-regulatory cells. Overall, we demonstrate that archaeosome adjuvants constitute an effective choice for formulating cancer vaccines.

  17. The prognostic benefit of tumour-infiltrating Natural Killer cells in endometrial cancer is dependent on concurrent overexpression of Human Leucocyte Antigen-E in the tumour microenvironment

    NARCIS (Netherlands)

    Versluis, M A C; Marchal, S; Plat, A; Bock, G.H.; Hall, T.; de Bruyn, K.M.T.; Hollema, H.; Nijman, Hans W

    2017-01-01

    BACKGROUND: Human Leucocyte Antigen- E (HLA-E) has been reported as both a positive and negative prognostic marker in cancer. This apparent discrepancy may be due to opposing actions of HLA-E on tumour-infiltrating immune cells. Therefore, we evaluated HLA-E expression and survival in relation to

  18. Targeted delivery of antigen to intestinal dendritic cells induces oral tolerance and prevents autoimmune diabetes in NOD mice.

    Science.gov (United States)

    Chen, Yulin; Wu, Jie; Wang, Jiajia; Zhang, Wenjing; Xu, Bohui; Xu, Xiaojun; Zong, Li

    2018-03-15

    The intestinal immune system is an ideal target to induce immune tolerance physiologically. However, the efficiency of oral protein antigen delivery is limited by degradation of the antigen in the gastrointestinal tract and poor uptake by antigen-presenting cells. Gut dendritic cells (DCs) are professional antigen-presenting cells that are prone to inducing antigen-specific immune tolerance. In this study, we delivered the antigen heat shock protein 65-6×P277 (H6P) directly to the gut DCs of NOD mice through oral vaccination with H6P-loaded targeting nanoparticles (NPs), and investigated the ability of this antigen to induce immune tolerance to prevent autoimmune diabetes in NOD mice. A targeting NP delivery system was developed to encapsulate H6P, and the ability of this system to protect and facilitate H6P delivery to gut DCs was assessed. NOD mice were immunised with H6P-loaded targeting NPs orally once a week for 7 weeks and the onset of diabetes was assessed by monitoring blood glucose levels. H6P-loaded targeting NPs protected the encapsulated H6P from degradation in the gastrointestinal tract environment and significantly increased the uptake of H6P by DCs in the gut Peyer's patches (4.1 times higher uptake compared with the control H6P solution group). Oral vaccination with H6P-loaded targeting NPs induced antigen-specific T cell tolerance and prevented diabetes in 100% of NOD mice. Immune deviation (T helper [Th]1 to Th2) and CD4 + CD25 + FOXP3 + regulatory T cells were found to participate in the induction of immune tolerance. In this study, we successfully induced antigen-specific T cell tolerance and prevented the onset of diabetes in NOD mice. To our knowledge, this is the first attempt at delivering antigen to gut DCs using targeting NPs to induce T cell tolerance.

  19. Expanded human blood-derived γδT cells display potent antigen-presentation functions

    Directory of Open Access Journals (Sweden)

    Mohd Wajid Ali Khan

    2014-07-01

    Full Text Available Cell-based immunotherapy strategies target tumors directly (via cytolytic effector cells or aim at mobilizing endogenous anti-tumor immunity. The latter approach includes dendritic cells (DC, most frequently in the form of in vitro cultured peripheral blood monocytes-derived DC. Human blood γδT cells are selective for a single class of non-peptide agonists (phosphoantigens and develop into potent antigen-presenting cells (APC, termed γδT-APC, within 1-3 days of in vitro culture. Availability of large numbers of γδT-APC would be advantageous for use as a novel cellular vaccine. We here report optimal γδT cell expansion (>107 cells/ml blood when peripheral blood mononuclear cells (PBMC from healthy individuals and melanoma patients were stimulated with zoledronate and then cultured for 14 days in the presence of IL-2 and IL-15, yielding γδT cell cultures of variable purity (77±21% and 56±26%, respectively. They resembled effector-memory αβT (TEM cells and retained full functionality as assessed by in vitro tumor cell killing as well as secretion of proinflammatory cytokines (IFNγ, TNFα and cell proliferation in response to stimulation with phosphoantigens. Importantly, day 14 γδT cells expressed numerous APC-related cell surface markers and, in agreement, displayed potent in vitro APC functions. Day 14 γδT cells from PBMC of patients with cancer were equally effective as their counterparts derived from blood of healthy individuals and triggered potent CD8+ αβT cell responses following processing and cross-presentation of simple (influenza M1 and complex (tuberculin purified protein derivative protein antigens. Of note, and in clear contrast to peripheral blood γδT cells, the ability of day 14 γδT cells to trigger antigen-specific αβT cell responses did not depend on re-stimulation. We conclude that day 14 γδT cell cultures provide a convenient source of autologous APC for use in immunotherapy of

  20. Co-stimulatory signaling determines tumor antigen sensitivity and persistence of CAR T cells targeting PSCA+ metastatic prostate cancer.

    Science.gov (United States)

    Priceman, Saul J; Gerdts, Ethan A; Tilakawardane, Dileshni; Kennewick, Kelly T; Murad, John P; Park, Anthony K; Jeang, Brook; Yamaguchi, Yukiko; Yang, Xin; Urak, Ryan; Weng, Lihong; Chang, Wen-Chung; Wright, Sarah; Pal, Sumanta; Reiter, Robert E; Wu, Anna M; Brown, Christine E; Forman, Stephen J

    2018-01-01

    Advancing chimeric antigen receptor (CAR)-engineered adoptive T cells for the treatment of solid cancers is a major focus in the field of immunotherapy, given impressive recent clinical responses in hematological malignancies. Prostate cancer may be amenable to T cell-based immunotherapy since several tumor antigens, including prostate stem-cell antigen (PSCA), are widely over-expressed in metastatic disease. While antigen selectivity of CARs for solid cancers is crucial, it is problematic due to the absence of truly restricted tumor antigen expression and potential safety concerns with "on-target off-tumor" activity. Here, we show that the intracellular co-stimulatory signaling domain can determine a CAR's sensitivity for tumor antigen expression. A 4-1BB intracellular co-stimulatory signaling domain in PSCA-CARs confers improved selectivity for higher tumor antigen density, reduced T cell exhaustion phenotype, and equivalent tumor killing ability compared to PSCA-CARs containing the CD28 co-stimulatory signaling domain. PSCA-CARs exhibit robust in vivo anti-tumor activity in patient-derived bone-metastatic prostate cancer xenograft models, and 4-1BB-containing CARs show superior T cell persistence and control of disease compared with CD28-containing CARs. Our study demonstrates the importance of co-stimulation in defining an optimal CAR T cell, and also highlights the significance of clinically relevant models in developing solid cancer CAR T cell therapies.

  1. Co-stimulatory signaling determines tumor antigen sensitivity and persistence of CAR T cells targeting PSCA+ metastatic prostate cancer

    Science.gov (United States)

    Priceman, Saul J.; Gerdts, Ethan A.; Tilakawardane, Dileshni; Kennewick, Kelly T.; Murad, John P.; Park, Anthony K.; Jeang, Brook; Yamaguchi, Yukiko; Urak, Ryan; Weng, Lihong; Chang, Wen-Chung; Wright, Sarah; Pal, Sumanta; Reiter, Robert E.; Brown, Christine E.; Forman, Stephen J.

    2018-01-01

    ABSTRACT Advancing chimeric antigen receptor (CAR)-engineered adoptive T cells for the treatment of solid cancers is a major focus in the field of immunotherapy, given impressive recent clinical responses in hematological malignancies. Prostate cancer may be amenable to T cell-based immunotherapy since several tumor antigens, including prostate stem-cell antigen (PSCA), are widely over-expressed in metastatic disease. While antigen selectivity of CARs for solid cancers is crucial, it is problematic due to the absence of truly restricted tumor antigen expression and potential safety concerns with “on-target off-tumor” activity. Here, we show that the intracellular co-stimulatory signaling domain can determine a CAR's sensitivity for tumor antigen expression. A 4-1BB intracellular co-stimulatory signaling domain in PSCA-CARs confers improved selectivity for higher tumor antigen density, reduced T cell exhaustion phenotype, and equivalent tumor killing ability compared to PSCA-CARs containing the CD28 co-stimulatory signaling domain. PSCA-CARs exhibit robust in vivo anti-tumor activity in patient-derived bone-metastatic prostate cancer xenograft models, and 4-1BB-containing CARs show superior T cell persistence and control of disease compared with CD28-containing CARs. Our study demonstrates the importance of co-stimulation in defining an optimal CAR T cell, and also highlights the significance of clinically relevant models in developing solid cancer CAR T cell therapies. PMID:29308300

  2. The location of splenic NKT cells favours their rapid activation by blood-borne antigen

    Science.gov (United States)

    Barral, Patricia; Sánchez-Niño, María Dolores; van Rooijen, Nico; Cerundolo, Vincenzo; Batista, Facundo D

    2012-01-01

    Natural killer T (NKT) cells play an important role in mounting protective responses to blood-borne infections. However, though the spleen is the largest blood filter in the body, the distribution and dynamics of NKT cells within this organ are not well characterized. Here we show that the majority of NKT cells patrol around the marginal zone (MZ) and red pulp (RP) of the spleen. In response to lipid antigen, these NKT cells become arrested and rapidly produce cytokines, while the small proportion of NKT cells located in the white pulp (WP) exhibit limited activation. Importantly, disruption of the splenic MZ by chemical or genetic approaches results in a severe reduction in NKT cell activation indicating the need of cooperation between both MZ macrophages and dendritic cells for efficient NKT cell responses. Thus, the location of splenic NKT cells in the MZ and RP facilitates their access to blood-borne antigen and enables the rapid initiation of protective immune responses. PMID:22505026

  3. Enhanced cytotoxicity of natural killer cells following the acquisition of chimeric antigen receptors through trogocytosis.

    Directory of Open Access Journals (Sweden)

    Fu-Nan Cho

    Full Text Available Natural killer (NK cells have the capacity to target tumors and are ideal candidates for immunotherapy. Viral vectors have been used to genetically modify in vitro expanded NK cells to express chimeric antigen receptors (CARs, which confer cytotoxicity against tumors. However, use of viral transduction methods raises the safety concern of viral integration into the NK cell genome. In this study, we used trogocytosis as a non-viral method to modify NK cells for immunotherapy. A K562 cell line expressing high levels of anti-CD19 CARs was generated as a donor cell to transfer the anti-CD19 CARs onto NK cells via trogocytosis. Anti-CD19 CAR expression was observed in expanded NK cells after these cells were co-cultured for one hour with freeze/thaw-treated donor cells expressing anti-CD19 CARs. Immunofluorescence analysis confirmed the localization of the anti-CD19 CARs on the NK cell surface. Acquisition of anti-CD19 CARs via trogocytosis enhanced NK cell-mediated cytotoxicity against the B-cell acute lymphoblastic leukemia (B-ALL cell lines and primary B-ALL cells derived from patients. To our knowledge, this is the first report that describes the increased cytotoxicity of NK cells following the acquisition of CARs via trogocytosis. This novel strategy could be a potential valuable therapeutic approach for the treatment of B-cell tumors.

  4. Enhanced cytotoxicity of natural killer cells following the acquisition of chimeric antigen receptors through trogocytosis.

    Science.gov (United States)

    Cho, Fu-Nan; Chang, Tsung-Hsien; Shu, Chih-Wen; Ko, Ming-Chin; Liao, Shuen-Kuei; Wu, Kang-Hsi; Yu, Ming-Sun; Lin, Shyh-Jer; Hong, Ying-Chung; Chen, Chien-Hsun; Hung, Chien-Hui; Chang, Yu-Hsiang

    2014-01-01

    Natural killer (NK) cells have the capacity to target tumors and are ideal candidates for immunotherapy. Viral vectors have been used to genetically modify in vitro expanded NK cells to express chimeric antigen receptors (CARs), which confer cytotoxicity against tumors. However, use of viral transduction methods raises the safety concern of viral integration into the NK cell genome. In this study, we used trogocytosis as a non-viral method to modify NK cells for immunotherapy. A K562 cell line expressing high levels of anti-CD19 CARs was generated as a donor cell to transfer the anti-CD19 CARs onto NK cells via trogocytosis. Anti-CD19 CAR expression was observed in expanded NK cells after these cells were co-cultured for one hour with freeze/thaw-treated donor cells expressing anti-CD19 CARs. Immunofluorescence analysis confirmed the localization of the anti-CD19 CARs on the NK cell surface. Acquisition of anti-CD19 CARs via trogocytosis enhanced NK cell-mediated cytotoxicity against the B-cell acute lymphoblastic leukemia (B-ALL) cell lines and primary B-ALL cells derived from patients. To our knowledge, this is the first report that describes the increased cytotoxicity of NK cells following the acquisition of CARs via trogocytosis. This novel strategy could be a potential valuable therapeutic approach for the treatment of B-cell tumors.

  5. IgM and IgD B cell receptors differentially respond to endogenous antigens and control B cell fate

    Science.gov (United States)

    Noviski, Mark; Mueller, James L; Satterthwaite, Anne; Garrett-Sinha, Lee Ann; Brombacher, Frank

    2018-01-01

    Naive B cells co-express two BCR isotypes, IgM and IgD, with identical antigen-binding domains but distinct constant regions. IgM but not IgD is downregulated on autoreactive B cells. Because these isotypes are presumed to be redundant, it is unknown how this could impose tolerance. We introduced the Nur77-eGFP reporter of BCR signaling into mice that express each BCR isotype alone. Despite signaling strongly in vitro, IgD is less sensitive than IgM to endogenous antigen in vivo and developmental fate decisions are skewed accordingly. IgD-only Lyn−/− B cells cannot generate autoantibodies and short-lived plasma cells (SLPCs) in vivo, a fate thought to be driven by intense BCR signaling induced by endogenous antigens. Similarly, IgD-only B cells generate normal germinal center, but impaired IgG1+ SLPC responses to T-dependent immunization. We propose a role for IgD in maintaining the quiescence of autoreactive B cells and restricting their differentiation into autoantibody secreting cells. PMID:29521626

  6. 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.

  7. Cell division cycle-associated protein 1 as a new melanoma-associated antigen.

    Science.gov (United States)

    Tokuzumi, Aki; Fukushima, Satoshi; Miyashita, Azusa; Nakahara, Satoshi; Kubo, Yosuke; Yamashita, Junji; Harada, Miho; Nakamura, Kayo; Kajihara, Ikko; Jinnin, Masatoshi; Ihn, Hironobu

    2016-12-01

    Immune checkpoint inhibitors have increased the median survival of melanoma patients. To improve their effects, antigen-specific therapies utilizing melanoma-associated antigens should be developed. Cell division cycle-associated protein 1 (CDCA1), which has a specific function at the kinetochores for stabilizing microtubule attachment, is overexpressed in various cancers. CDCA1, which is a member of cancer-testis antigens, does not show detectable expression levels in normal tissues. Quantitative reverse transcription polymerase chain reaction and immunoblotting analyses revealed that CDCA1 was expressed in all of the tested melanoma cell lines, 74% of primary melanomas, 64% of metastatic melanomas and 25% of nevi. An immunohistochemical analysis and a Cox proportional hazards model showed that CDCA1 could be a prognostic marker in malignant melanoma (MM) patients. CDCA1-specific siRNA inhibited the cell proliferation of SKMEL2 and WM115 cells, but did not reduce the migration or invasion activity. These results suggest that CDCA1 may be a new therapeutic target of melanoma. © 2016 Japanese Dermatological Association.

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

    OpenAIRE

    Manfredi AA; Rovere-Querini P

    2004-01-01

    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 s...

  9. Localization of functional memory B cells at sites of antigen localization and its relationship to local aspects of immunological memory

    International Nuclear Information System (INIS)

    Ponzio, N.M.; Baine, Y.; Thorbecke, G.J.

    1980-01-01

    Experiments are described which have been designed to test whether antigen in a draining lymph node can mediate local accumulation of passively transferred antigen-specific memory B cells, using recipients whose own immune response is inhibited via γ-irradiation or by injection of cyclophosphamide. (Auth.)

  10. A radioimmunoassay for antibodies against surface membrane antigens using adhering cells

    International Nuclear Information System (INIS)

    Tax, A.; Manson, L.A.

    1976-01-01

    A radioimmunoassay using cells adhering to plastic is described. In this assay, A-10 mammary carcinoma attached to the surface of plastic in microtiter plates were permitted to bind antibody and the bound antibody was detected with purified rabbit 125 I-antimouse-Fab. The bound radioactive material was eluted with glycine-HCl buffer (pH 2.5), and the acid eluates were counted in a gamma counter. This assay can be used to detect cytolic or noncytolic antibody to cell surface antigens in studies with any tumor or normal cell that will adhere to a solid surface

  11. Chimeric antigen receptor (CAR T cell therapy for malignant cancers: Summary and perspective

    Directory of Open Access Journals (Sweden)

    Aaron J. Smith

    2016-11-01

    Full Text Available This paper will summarize the data obtained primarily from the last decade of chimeric antigen receptor (CAR T cell immunotherapy. It will do so in a manner that provides an overview needed to set the foundation for perspective on the state of research associated with CAR T cell therapy. The topics covered will include the construction of engineered CAR T cells from the standpoint of the different generations, the mode in which autologous T cells are transfected, the various biomarkers that have been used in CAR T cell immunotherapy, and setbacks associated with engineered T cells. Perspective on priorities of CAR T cell immunotherapy will also be addressed as they are related to safety and efficacy.

  12. Increasing the safety and efficacy of chimeric antigen receptor T cell therapy

    Directory of Open Access Journals (Sweden)

    Hua Li

    2017-04-01

    Full Text Available Abstract Chimeric antigen receptor (CAR T cell therapy is a promising cancer treatment that has recently been undergoing rapid development. However, there are still some major challenges, including precise tumor targeting to avoid off-target or “on-target/off-tumor” toxicity, adequate T cell infiltration and migration to solid tumors and T cell proliferation and persistence across the physical and biochemical barriers of solid tumors. In this review, we focus on the primary challenges and strategies to design safe and effective CAR T cells, including using novel cutting-edge technologies for CAR and vector designs to increase both the safety and efficacy, further T cell modification to overcome the tumor-associated immune suppression, and using gene editing technologies to generate universal CAR T cells. All these efforts promote the development and evolution of CAR T cell therapy and move toward our ultimate goal—curing cancer with high safety, high efficacy, and low cost.

  13. Chimeric-antigen receptor T (CAR-T) cell therapy for solid tumors: challenges and opportunities.

    Science.gov (United States)

    Xia, An-Liang; Wang, Xiao-Chen; Lu, Yi-Jun; Lu, Xiao-Jie; Sun, Beicheng

    2017-10-27

    Chimeric antigen receptor (CAR)-engineered T cells (CAR-T cells) have been shown to have unprecedented efficacy in B cell malignancies, most notably in B cell acute lymphoblastic leukemia (B-ALL) with up to a 90% complete remission rate using anti-CD19 CAR-T cells. However, CAR T-cell therapy for solid tumors currently is faced with numerous challenges such as physical barriers, the immunosuppressive tumor microenvironment and the specificity and safety. The clinical results in solid tumors have been much less encouraging, with multiple cases of toxicity and a lack of therapeutic response. In this review, we will discuss the current stats and challenges of CAR-T cell therapy for solid tumors, and propose possibl e solutions and future perspectives.

  14. Spontaneous loss and alteration of antigen receptor expression in mature CD4+ T cells

    International Nuclear Information System (INIS)

    Kyoizumi, Seishi; Akiyama, Mitoshi; Hirai, Yuko; Kusunoki; Yoichiro; Tanabe, Kazumi; Umeki, Shigeko; Nakamura, Nori; Yamakido, Michio; Hamamoto, Kazuko.

    1990-04-01

    The T-cell receptor CD3 (TCR/CD3) complex plays a central role in antigen recognition and activation of mature T cells, and therefore abnormalities in the expression of the complex should induce unresponsiveness of T cells to antigen stimulus. Using flow cytometry, we detected and enumerated variant cells with loss or alteration of surface TCR/CD3 expression among human mature CD4 + T cells. The presence of variant CD4 + T cells was demonstrated by isolating and cloning them from peripheral blood, and their abnormalities can be accounted for by alterations in TCR expression such as defects of protein expression and partial protein deletion. The variant frequency in peripheral blood increased with aging in normal donors and was highly elevated in patients with ataxia telangiectasia, an autosomal recessive inherited disease with defective DNA repair and variable T-cell immunodeficiency. These findings suggest that such alterations in TCR expression are induced by somatic mutagenesis of TCR genes and can be important factors related to age-dependent and genetic disease-associated T-cell dysfunction. (author)

  15. 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.

  16. Chimeric Antigen Receptor Expressing Natural Killer Cells for the Immunotherapy of Cancer

    Directory of Open Access Journals (Sweden)

    Rohtesh S. Mehta

    2018-02-01

    Full Text Available Adoptive cell therapy has emerged as a powerful treatment for advanced cancers resistant to conventional agents. Most notable are the remarkable responses seen in patients receiving autologous CD19-redirected chimeric antigen receptor (CAR T cells for the treatment of B lymphoid malignancies; however, the generation of autologous products for each patient is logistically cumbersome and has restricted widespread clinical use. A banked allogeneic product has the potential to overcome these limitations, yet allogeneic T-cells (even if human leukocyte antigen-matched carry a major risk of graft-versus-host disease (GVHD. Natural killer (NK cells are bone marrow-derived innate lymphocytes that can eliminate tumors directly, with their activity governed by the integration of signals from activating and inhibitory receptors and from cytokines including IL-15, IL-12, and IL-18. NK cells do not cause GVHD or other alloimmune or autoimmune toxicities and thus, can provide a potential source of allogeneic “off-the-shelf” cellular therapy, mediating major anti-tumor effects without inducing potentially lethal alloreactivity such as GVHD. Given the multiple unique advantages of NK cells, researchers are now exploring the use of CAR-engineered NK cells for the treatment of various hematological and non-hematological malignancies. Herein, we review preclinical data on the development of CAR-NK cells, advantages, disadvantages, and current obstacles to their clinical use.

  17. Performance-enhancing drugs: design and production of redirected chimeric antigen receptor (CAR) T cells.

    Science.gov (United States)

    Levine, B L

    2015-03-01

    Performance enhancement of the immune system can now be generated through ex vivo gene modification of T cells in order to redirect native specificity to target tumor antigens. This approach combines the specificity of antibody therapy, the expanded response of cellular therapy and the memory activity of vaccine therapy. Recent clinical trials of chimeric antigen receptor (CAR) T cells directed toward CD19 as a stand-alone therapy have shown sustained complete responses in patients with acute lymphoblastic leukemia and chronic lymphocytic leukemia. As these drug products are individually derived from a patient's own cells, a different manufacturing approach is required for this kind of personalized therapy compared with conventional drugs. Key steps in the CAR T-cell manufacturing process include the selection and activation of isolated T cells, transduction of T cells to express CARs, ex vivo expansion of modified T cells and cryopreservation in infusible media. In this review, the steps involved in isolating, genetically modifying and scaling-out the CAR T cells for use in a clinical setting are described in the context of in-process and release testing and regulatory standards.

  18. Improved Activation toward Primary Colorectal Cancer Cells by Antigen-Specific Targeting Autologous Cytokine-Induced Killer Cells

    Directory of Open Access Journals (Sweden)

    Claudia Schlimper

    2012-01-01

    Full Text Available Adoptive therapy of malignant diseases with cytokine-induced killer (CIK cells showed promise in a number of trials; the activation of CIK cells from cancer patients towards their autologous cancer cells still needs to be improved. Here, we generated CIK cells ex vivo from blood lymphocytes of colorectal cancer patients and engineered those cells with a chimeric antigen receptor (CAR with an antibody-defined specificity for carcinoembryonic antigen (CEA. CIK cells thereby gained a new specificity as defined by the CAR and showed increase in activation towards CEA+ colon carcinoma cells, but less in presence of CEA− cells, indicated by increased secretion of proinflammatory cytokines. Redirected CIK activation was superior by CAR-mediated CD28-CD3ζ than CD3ζ signaling only. CAR-engineered CIK cells from colon carcinoma patients showed improved activation against their autologous, primary carcinoma cells from biopsies resulting in more efficient tumour cell lysis. We assume that adoptive therapy with CAR-modified CIK cells shows improved selectivity in targeting autologous tumour lesions.

  19. Electrophoretic analysis of the "cross-class" interaction between novel inhibitory serpin, squamous cell carcinoma antigen-1 and cysteine proteinases.

    Science.gov (United States)

    Nawata, S; Nakamura, K; Tanaka, T; Numa, F; Suminami, Y; Tsunaga, N; Kakegawa, H; Katunuma, N; Kato, H

    1997-05-01

    We investigated the "cross-class" interaction between cysteine proteinases and a novel inhibitory serpin, recombinant squamous cell carcinoma (rSCC) antigen-1, which inhibits a serine proteinase, chymotrypsin. rSCC antigen-1 inhibited the cysteine proteinases, papain, papaya proteinase IV and cathepsin L. Interestingly, although rSCC antigen-1 formed sodium dodecyl sulfate (SDS)- and heat-stable complexes with chymotrypsin, rSCC antigen-1 gave the 40 kDa fragment and small molecular mass peptide by incubation with papain without forming an SDS- and heat-stable complex. The cleavage was observed between the Gly353-Ser354 bond, indicating that rSCC antigen-1 interacts with cysteine proteinases not at the predicted reactive site P1-P1' portion (Ser354-Ser355), but at the Gly353-Ser354 of the P2-P1 portion. These findings promote understanding of the "suicide inhibition" mechanism of SCC antigen-1 against cysteine proteinases.

  20. Cytotoxic T cells in chronic idiopathic neutropenia express restricted antigen receptors.

    Science.gov (United States)

    Mastrodemou, Semeli; Stalika, Evangelia; Vardi, Anna; Gemenetzi, Katerina; Spanoudakis, Michalis; Karypidou, Maria; Mavroudi, Irene; Hadzidimitriou, Anastasia; Stavropoulos-Giokas, Catherine; Papadaki, Helen A; Stamatopoulos, Kostas

    2017-12-01

    Chronic idiopathic neutropenia (CIN) is an acquired disorder of granulopoiesis characterized by female predominance and mostly uncomplicated course. Crucial to CIN pathophysiology is the presence of activated T lymphocytes with myelosuppressive properties in both peripheral blood (PB) and bone marrow (BM). We systematically profiled the T cell receptor beta chain (TRB) gene repertoire in CD8 + cells of 34 CIN patients through subcloning/Sanger sequencing analysis of TRBV-TRBD-TRBJ gene rearrangements. Remarkable repertoire skewing and oligoclonality were observed, along with shared clonotypes between different patients, alluding to antigen selection. Cross-comparison of our sequence dataset with public TRB sequence databases revealed that CIN may rarely share common immunogenetic features with other entities, however, the CIN TRB repertoire is largely disease-biased. Overall, these findings suggest that CIN may be driven by long-term exposure to a restricted set of specific CIN-associated antigens.

  1. 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.

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

    Science.gov (United States)

    Kornum, Birgitte Rahbek; Kenny, Eimear E.; Trynka, Gosia; Einen, Mali; Rico, Tom J.; Lichtner, Peter; Dauvilliers, Yves; Arnulf, Isabelle; Lecendreux, Michel; Javidi, Sirous; Geisler, Peter; Mayer, Geert; Pizza, Fabio; Poli, Francesca; Plazzi, Giuseppe; Overeem, Sebastiaan; Lammers, Gert Jan; Kemlink, David; Sonka, Karel; Nevsimalova, Sona; Rouleau, Guy; Desautels, Alex; Montplaisir, Jacques; Frauscher, Birgit; Ehrmann, Laura; Högl, Birgit; Jennum, Poul; Bourgin, Patrice; Peraita-Adrados, Rosa; Iranzo, Alex; Bassetti, Claudio; Chen, Wei-Min; Concannon, Patrick; Thompson, Susan D.; Damotte, Vincent; Fontaine, Bertrand; Breban, Maxime; Gieger, Christian; Klopp, Norman; Deloukas, Panos; Wijmenga, Cisca; Hallmayer, Joachim; Onengut-Gumuscu, Suna; Rich, Stephen S.; Winkelmann, Juliane; Mignot, Emmanuel

    2013-01-01

    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. PMID:23459209

  3. Homology-Directed Recombination for Enhanced Engineering of Chimeric Antigen Receptor T Cells

    Directory of Open Access Journals (Sweden)

    Malika Hale

    2017-03-01

    Full Text Available Gene editing by homology-directed recombination (HDR can be used to couple delivery of a therapeutic gene cassette with targeted genomic modifications to generate engineered human T cells with clinically useful profiles. Here, we explore the functionality of therapeutic cassettes delivered by these means and test the flexibility of this approach to clinically relevant alleles. Because CCR5-negative T cells are resistant to HIV-1 infection, CCR5-negative anti-CD19 chimeric antigen receptor (CAR T cells could be used to treat patients with HIV-associated B cell malignancies. We show that targeted delivery of an anti-CD19 CAR cassette to the CCR5 locus using a recombinant AAV homology template and an engineered megaTAL nuclease results in T cells that are functionally equivalent, in both in vitro and in vivo tumor models, to CAR T cells generated by random integration using lentiviral delivery. With the goal of developing off-the-shelf CAR T cell therapies, we next targeted CARs to the T cell receptor alpha constant (TRAC locus by HDR, producing TCR-negative anti-CD19 CAR and anti-B cell maturation antigen (BCMA CAR T cells. These novel cell products exhibited in vitro cytolytic activity against both tumor cell lines and primary cell targets. Our combined results indicate that high-efficiency HDR delivery of therapeutic genes may provide a flexible and robust method that can extend the clinical utility of cell therapeutics.

  4. Therapy of HPV 16-associated carcinoma with dendritic cell-based vaccines: In vitro priming of the effector cell responses by DC pulsed with tumour lysates and synthetic RAHYNIVTF peptide

    Czech Academy of Sciences Publication Activity Database

    Indrová, Marie; Bubeník, Jan; Šímová, Jana; Vonka, V.; Němečková, Š.; Mendoza, Luis; Reiniš, Milan

    2001-01-01

    Roč. 7, č. 1 (2001), s. 97-100 ISSN 1107-3756 R&D Projects: GA MZd NC5526; GA MZd NC45011; GA ČR GA312/98/0826; GA ČR GA312/99/0542; GA ČR GA301/00/0114; GA AV ČR IAA7052002 Institutional research plan: CEZ:AV0Z5052915 Keywords : tumour vaccines * HPV 16 * dendritic cells Subject RIV: FD - Oncology ; Hematology Impact factor: 1.689, year: 2001

  5. Reduced response to Epstein-Barr virus antigens by T-cells in systemic lupus erythematosus patients

    DEFF Research Database (Denmark)

    Draborg, Anette Holck; Jacobsen, Søren; Westergaard, Marie

    2014-01-01

    OBJECTIVE: Epstein-Barr virus (EBV) has for long been associated with systemic lupus erythematosus (SLE). In this study, we investigated the levels of latent and lytic antigen EBV-specific T-cells and antibodies in SLE patients. METHODS: T cells were analyzed by flow cytometry and antibodies were...... analyzed by enzyme-linked immunosorbent assay. RESULTS: SLE patients showed a significantly reduced number of activated (CD69) T-cells upon ex vivo stimulation with EBV nuclear antigen (EBNA) 1 or EBV early antigen diffuse (EBV-EA/D) in whole blood samples compared with healthy controls. Also, a reduced...... number of T-cells from SLE patients were found to produce interferon-γ upon stimulation with these antigens. Importantly, responses to a superantigen were normal in SLE patients. Compared with healthy controls, SLE patients had fewer EBV-specific T-cells but higher titres of antibodies against EBV...

  6. Induction of CD8+ T-cell responses against subunit antigens by the novel cationic liposomal CAF09 adjuvant

    DEFF Research Database (Denmark)

    Korsholm, Karen Smith; Hansen, Jon; Karlsen, Kasper

    2014-01-01

    Vaccines inducing cytotoxic T-cell responses are required to achieve protection against cancers and intracellular infections such as HIV and Hepatitis C virus. Induction of CD8+ T cell responses in animal models can be achieved by the use of viral vectors or DNA vaccines but so far without much...... clinical success. Here we describe the novel CD8+ T-cell inducing adjuvant, cationic adjuvant formulation (CAF) 09, consisting of dimethyldioctadecylammonium (DDA)-liposomes stabilized with monomycoloyl glycerol (MMG)-1 and combined with the TLR3 ligand, Poly(I:C). Different antigens from tuberculosis (TB......10.3, H56), HIV (Gag p24), HPV (E7) and the model antigen ovalbumin were formulated with CAF09 and administering these vaccines to mice resulted in a high frequency of antigen-specific CD8+ T cells. CAF09 was superior in its ability to induce antigen-specific CD8+ T cells as compared to other...

  7. Interferon regulatory factor 8 regulates pathways for antigen presentation in myeloid cells and during tuberculosis.

    Directory of Open Access Journals (Sweden)

    Jean-François Marquis

    2011-06-01

    Full Text Available IRF8 (Interferon Regulatory Factor 8 plays an important role in defenses against intracellular pathogens, including several aspects of myeloid cells function. It is required for ontogeny and maturation of macrophages and dendritic cells, for activation of anti-microbial defenses, and for production of the Th1-polarizing cytokine interleukin-12 (IL-12 in response to interferon gamma (IFNγ and protection against infection with Mycobacterium tuberculosis. The transcriptional programs and cellular pathways that are regulated by IRF8 in response to IFNγ and that are important for defenses against M. tuberculosis are poorly understood. These were investigated by transcript profiling and chromatin immunoprecipitation on microarrays (ChIP-chip. Studies in primary macrophages identified 368 genes that are regulated by IRF8 in response to IFNγ/CpG and that behave as stably segregating expression signatures (eQTLs in F2 mice fixed for a wild-type or mutant allele at IRF8. A total of 319 IRF8 binding sites were identified on promoters genome-wide (ChIP-chip in macrophages treated with IFNγ/CpG, defining a functional G/AGAAnTGAAA motif. An analysis of the genes bearing a functional IRF8 binding site, and showing regulation by IFNγ/CpG in macrophages and/or in M. tuberculosis-infected lungs, revealed a striking enrichment for the pathways of antigen processing and presentation, including multiple structural and enzymatic components of the Class I and Class II MHC (major histocompatibility complex antigen presentation machinery. Also significantly enriched as IRF8 targets are the group of endomembrane- and phagosome-associated small GTPases of the IRG (immunity-related GTPases and GBP (guanylate binding proteins families. These results identify IRF8 as a key regulator of early response pathways in myeloid cells, including phagosome maturation, antigen processing, and antigen presentation by myeloid cells.

  8. Role of CD5-negative CD8 T Cells in Adaptation to Antigenic ...

    African Journals Online (AJOL)

    Role of CD5-negative CD8. +. T Cells in Adaptation to. Antigenic Variation of Human Immunodeficiency Virus. Type 1. Xin-Yun Zhang1, Jian-Rong Zhao2, .... time point. The viral load was decreased to < 350 copies per mL at each of the follow-up time-points (Table 1). We also observed a remarkable change in the level of ...

  9. 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.

  10. EBV-transformed lymphoblastoid cell lines as vaccines against cancer testis antigen-positive tumors.

    Science.gov (United States)

    Neumann, Frank; Kaddu-Mulindwa, Dominic; Widmann, Thomas; Preuss, Klaus-Dieter; Held, Gerhard; Zwick, Carsten; Roemer, Klaus; Pfreundschuh, Michael; Kubuschok, Boris

    2013-07-01

    EBV-transformed lymphoblastoid cell lines (LCL) are potent antigen-presenting cells. To investigate their potential use as cancer testis antigen (CTA) vaccines, we studied the expression of 12 cancer testis (CT) genes in 20 LCL by RT-PCR. The most frequently expressed CT genes were SSX4 (50 %), followed by GAGE (45 %), SSX1 (40 %), MAGE-A3 and SSX2 (25 %), SCP1, HOM-TES-85, MAGE-C1, and MAGE-C2 (15 %). NY-ESO-1 and MAGE-A4 were found in 1/20 LCL and BORIS was not detected at all. Fifteen of 20 LCL expressed at least one antigen, 9 LCL expressed ≥2 CT genes, and 7 of the 20 LCL expressed ≥4 CT genes. The expression of CT genes did not correlate with the length of in vitro culture, telomerase activity, aneuploidy, or proliferation state. While spontaneous expression of CT genes determined by real-time PCR and Western blot was rather weak in most LCL, treatment with DNA methyltransferase 1 inhibitor alone or in combination with histone deacetylase inhibitors increased CTA expression considerably thus enabling LCL to induce CTA-specific T cell responses. The stability of the CT gene expression over prolonged culture periods makes LCL attractive candidates for CT vaccines both in hematological neoplasias and solid tumors.

  11. A new insight in chimeric antigen receptor-engineered T cells for cancer immunotherapy

    Directory of Open Access Journals (Sweden)

    Erhao Zhang

    2017-01-01

    Full Text Available Abstract Adoptive cell therapy using chimeric antigen receptor (CAR-engineered T cells has emerged as a very promising approach to combating cancer. Despite its ability to eliminate tumors shown in some clinical trials, CAR-T cell therapy involves some significant safety challenges, such as cytokine release syndrome (CRS and “on-target, off-tumor” toxicity, which is related to poor control of the dose, location, and timing of T cell activity. In the past few years, some strategies to avoid the side effects of CAR-T cell therapy have been reported, including suicide gene, inhibitory CAR, dual-antigen receptor, and the use of exogenous molecules as switches to control the CAR-T cell functions. Because of the advances of the CAR paradigm and other forms of cancer immunotherapy, the most effective means of defeating the cancer has become the integration therapy with the combinatorial control system of switchable dual-receptor CAR-T cell and immune checkpoint blockade.

  12. Automated manufacturing of chimeric antigen receptor T cells for adoptive immunotherapy using CliniMACS prodigy.

    Science.gov (United States)

    Mock, Ulrike; Nickolay, Lauren; Philip, Brian; Cheung, Gordon Weng-Kit; Zhan, Hong; Johnston, Ian C D; Kaiser, Andrew D; Peggs, Karl; Pule, Martin; Thrasher, Adrian J; Qasim, Waseem

    2016-08-01

    Novel cell therapies derived from human T lymphocytes are exhibiting enormous potential in early-phase clinical trials in patients with hematologic malignancies. Ex vivo modification of T cells is currently limited to a small number of centers with the required infrastructure and expertise. The process requires isolation, activation, transduction, expansion and cryopreservation steps. To simplify procedures and widen applicability for clinical therapies, automation of these procedures is being developed. The CliniMACS Prodigy (Miltenyi Biotec) has recently been adapted for lentiviral transduction of T cells and here we analyse the feasibility of a clinically compliant T-cell engineering process for the manufacture of T cells encoding chimeric antigen receptors (CAR) for CD19 (CAR19), a widely targeted antigen in B-cell malignancies. Using a closed, single-use tubing set we processed mononuclear cells from fresh or frozen leukapheresis harvests collected from healthy volunteer donors. Cells were phenotyped and subjected to automated processing and activation using TransAct, a polymeric nanomatrix activation reagent incorporating CD3/CD28-specific antibodies. Cells were then transduced and expanded in the CentriCult-Unit of the tubing set, under stabilized culture conditions with automated feeding and media exchange. The process was continuously monitored to determine kinetics of expansion, transduction efficiency and phenotype of the engineered cells in comparison with small-scale transductions run in parallel. We found that transduction efficiencies, phenotype and function of CAR19 T cells were comparable with existing procedures and overall T-cell yields sufficient for anticipated therapeutic dosing. The automation of closed-system T-cell engineering should improve dissemination of emerging immunotherapies and greatly widen applicability. Copyright © 2016. Published by Elsevier Inc.

  13. A Toll-like receptor 2 agonist-fused antigen enhanced antitumor immunity by increasing antigen presentation and the CD8 memory T cells population.

    Science.gov (United States)

    Wu, Chiao-Chieh; Liu, Shih-Jen; Chen, Hsin-Wei; Shen, Kuan-Yin; Leng, Chih-Hsiang

    2016-05-24

    The induction of long-lived effector CD8+ T cells is key to the development of efficient cancer vaccines. In this study, we demonstrated that a Toll-like receptor 2 (TLR2) agonist-fused antigen increased antigen presentation via TLR2 signaling and induced effector memory-like CD8+ T cells against cancer after immunization. The N-terminus of ovalbumin (OVA) was biologically fused with a bacterial lipid moiety TLR2 agonist to produce a recombinant lipidated ovalbumin (rlipo-OVA). We demonstrated that rlipo-OVA activated bone marrow-derived dendritic cells (BM-DCs) maturation and increased antigen presentation by major histocompatibility complex (MHC) class I via TLR2. After immunization, rlipo-OVA skewed the immune response towards T helper (Th) 1 and induced OVA-specific cytotoxic T lymphocyte (CTL) responses. Moreover, immunization with rlipo-OVA induced higher numbers of effector memory (CD44+CD62L-) CD8+ T cells compared with recombinant ovalbumin (rOVA) alone or rOVA mixed with the TLR2 agonist Pam3CSK4. Accordingly, the CD27+CD43+ effector memory CD8+ T cells expressed high levels of the long-lived CD127 marker. The administration of rlipo-OVA could inhibit tumor growth, but the anti-tumor effects were lost after the depletion of CD8 or CD127 cells in vivo. These findings suggested that the TLR2 agonist-fused antigen induced long-lived memory CD8+ T cells for efficient cancer therapy.

  14. Assessment of CD37 B-cell antigen and cell of origin significantly improves risk prediction in diffuse large B-cell lymphoma

    NARCIS (Netherlands)

    Xu-Monette, Z.Y.; Li, L; Byrd, J.C.; Jabbar, K.J.; Manyam, G.C.; Winde, C. Maria de; Brand, M. van den; Tzankov, A.; Visco, C.; Wang, J; Dybkaer, K.; Chiu, A.; Orazi, A.; Zu, Y.; Bhagat, G.; Richards, K.L.; Hsi, E.D.; Choi, W.W.; Huh, J.; Ponzoni, M.; Ferreri, A.J.; Moller, M.B.; Parsons, B.M.; Winter, J.N.; Wang, M.; Hagemeister, F.B.; Piris, M.A.; Krieken, J.H. van; Medeiros, L.J.; Li, Y.; Spriel, A.B. van; Young, K.H.

    2016-01-01

    CD37 (tetraspanin TSPAN26) is a B-cell surface antigen widely expressed on mature B cells. CD37 is involved in immune regulation and tumor suppression but its function has not been fully elucidated. We assessed CD37 expression in de novo diffuse large B-cell lymphoma (DLBCL), and investigated its

  15. Acute lymphoblastic leukemia-derived dendritic cells express tumor associated antigens: PNPT1, PMPCB, RHAMM, BSG and ERCC1.

    Science.gov (United States)

    Luczynski, W; Kowalczuk, O; Stasiak-Barmuta, A; Ilendo, E; Krawczuk-Rybak, M; Chyczewski, L

    2009-01-01

    In all types of leukemia both in children and adults there is a need for novel therapies that could reduce the risk of relapse after standard treatment. Acute lymphoblastic leukemia (ALL) cells are ineffective antigen presenting cells, but as shown by many authors including results from our laboratory, stimulation with CD40L restores their antigen expressing capacity. The development of T-cell therapies for leukemic patients can be based on discovery of leukemia-associated antigens (LAA) which could be recognized by the host immune system. The aim of our present study was to test the hypothesis that leukemia-derived dendritic cells maintain the expression of tumor associated antigens. Twenty five children with B-cell precursor ALL were prospectively enrolled into the study. The mononuclear cells from peripheral blood or bone marrow were cultured and stimulated (or not) with CD40L and IL-4. The assessment of costimulatory/adhesion molecules with the use of flow cytometry and real-time RT PCR were used to confirm the possibility of turning ALL cells into dendritic-like cells. Additionally 22 tumor associated antigens mRNA levels were determined by real-time PCR technique with the TaqMan chemistry using ready-to-use Low Density Arrays for Gene Expression. The results of the study showed maintained expression and even up-regulation of some (PNPT1, PMPCB, HMMR/RHAMM, BSG and ERCC1) tumor associated antigens in CD40-activated leukemic cells. CD40L stimulation leading to the differentiation of leukemic cells into DCs which combine both antigen presenting function and expression of tumor associated antigens represents an interesting approach in cancer immunotherapy.

  16. The role of MHC class II antigenic determinants in the function of human antigen binding T8+ cells, monocytes and helper and suppressor factors.

    Science.gov (United States)

    Lehner, T; Jones, T

    1984-06-01

    The role of MHC class II antigens was investigated in the process of antigen binding by T8+ cells and monocytes (Mo) and in the functions of helper factor (HF) and suppressor factor (SF). Monoclonal antibodies (MoAbs) to HLA-DR, DC and SB determinants were used in immunofluorescence, inhibition of antigen binding and affinity chromatography of HF and SF. Indirect immunofluorescence studies suggest that T lymphocytes from peripheral blood of healthy subjects have a small proportion of cells expressing HLA-DR, beta chain determinants (1.4-3.8%). These belong predominantly to the T8+ subset of cells (4.6-8.8%), with only a very small proportion in the T4+ cells (0.1-1.8%). However, DC1 on DRw6+ T cells and SB2,3 on any HLA typed cells were found in significantly greater proportion than the DR antigens in both T8+ and T4+ cells, though this was again greater on T8+ (30 and 25%) than T4+ (8.3 and 14.4%) cells. Although Mo had a greatly increased proportion of cells with DR-beta chain determinants (27-45%) than the T8+ cells, the converse was found with DC1 and SB2,3 determinants (13.9 and 11.4%). Inhibition of 125I-streptococcal antigen (SA) binding to T8+ cells and to Mo by MoAbs to the class II antigens showed that DR-beta chain monomorphic or polymorphic antibodies and DC1 antibodies inhibited binding to both cell types by 66-94%. However, MoAbs to DR-alpha chains or to the SB2,3 determinant failed to yield significant inhibition. Affinity chromatography studies of HF and SF revealed that the DR-beta chain monomorphic and DC1 antibodies bound HF and SF activities and that this was not found with the DR-beta chain polymorphic or SB2,3 antibodies. The results of inhibition of 125I-SA binding to T8+ cells and Mo, and absorption of HF and SF by affinity chromatography with MoAbs suggest four categories of recognition of human MHC class II antigenic determinants. (1) Class II determinants shared by the T8+ cells, Mo, HF and SF and recognized by MoAbs to monomorphic beta

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

    Directory of Open Access Journals (Sweden)

    Farrell Regina M

    2004-09-01

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

  18. cells targeting a neuronal paraneoplastic antigen mediate tumor rejection and trigger CNS autoimmunity with humoral activation.

    Science.gov (United States)

    Blachère, Nathalie E; Orange, Dana E; Santomasso, Bianca D; Doerner, Jessica; Foo, Patricia K; Herre, Margaret; Fak, John; Monette, Sébastien; Gantman, Emily C; Frank, Mayu O; Darnell, Robert B

    2014-11-01

    Paraneoplastic neurologic diseases (PND) involving immune responses directed toward intracellular antigens are poorly understood. Here, we examine immunity to the PND antigen Nova2, which is expressed exclusively in central nervous system (CNS) neurons. We hypothesized that ectopic expression of neuronal antigen in the periphery could incite PND. In our C57BL/6 mouse model, CNS antigen expression limits antigen-specific CD4+ and CD8+ T-cell expansion. Chimera experiments demonstrate that this tolerance is mediated by antigen expression in nonhematopoietic cells. CNS antigen expression does not limit tumor rejection by adoptively transferred transgenic T cells but does limit the generation of a memory population that can be expanded upon secondary challenge in vivo. Despite mediating cancer rejection, adoptively transferred transgenic T cells do not lead to paraneoplastic neuronal targeting. Preliminary experiments suggest an additional requirement for humoral activation to induce CNS autoimmunity. This work provides evidence that the requirements for cancer immunity and neuronal autoimmunity are uncoupled. Since humoral immunity was not required for tumor rejection, B-cell targeting therapy, such as rituximab, may be a rational treatment option for PND that does not hamper tumor immunity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Comparative analyses of industrial-scale human platelet lysate preparations.

    Science.gov (United States)

    Pierce, Jan; Benedetti, Eric; Preslar, Amber; Jacobson, Pam; Jin, Ping; Stroncek, David F; Reems, Jo-Anna

    2017-12-01

    Efforts are underway to eliminate fetal bovine serum from mammalian cell cultures for clinical use. An emerging, viable replacement option for fetal bovine serum is human platelet lysate (PL) as either a plasma-based or serum-based product. Nine industrial-scale, serum-based PL manufacturing runs (i.e., lots) were performed, consisting of an average ± standard deviation volume of 24.6 ± 2.2 liters of pooled, platelet-rich plasma units that were obtained from apheresis donors. Manufactured lots were compared by evaluating various biochemical and functional test results. Comprehensive cytokine profiles of PL lots and product stability tests were performed. Global gene expression profiles of mesenchymal stromal cells (MSCs) cultured with plasma-based or serum-based PL were compared to MSCs cultured with fetal bovine serum. Electrolyte and protein levels were relatively consistent among all serum-based PL lots, with only slight variations in glucose and calcium levels. All nine lots were as good as or better than fetal bovine serum in expanding MSCs. Serum-based PL stored at -80°C remained stable over 2 years. Quantitative cytokine arrays showed similarities as well as dissimilarities in the proteins present in serum-based PL. Greater differences in MSC gene expression profiles were attributable to the starting cell source rather than with the use of either PL or fetal bovine serum as a culture supplement. Using a large-scale, standardized method, lot-to-lot variations were noted for industrial-scale preparations of serum-based PL products. However, all lots performed as well as or better than fetal bovine serum in supporting MSC growth. Together, these data indicate that off-the-shelf PL is a feasible substitute for fetal bovine serum in MSC cultures. © 2017 AABB.

  20. Antigen Requirements for Efficient Priming of CD8+ T Cells by Leishmania major-Infected Dendritic Cells

    Science.gov (United States)

    Bertholet, Sylvie; Debrabant, Alain; Afrin, Farhat; Caler, Elisabeth; Mendez, Susana; Tabbara, Khaled S.; Belkaid, Yasmine; Sacks, David L.

    2005-01-01

    CD4+ and CD8+ T-cell responses have been shown to be critical for the development and maintenance of acquired resistance to infections with the protozoan parasite Leishmania major. Monitoring the development of immunodominant or clonally restricted T-cell subsets in response to infection has been difficult, however, due to the paucity of known epitopes. We have analyzed the potential of L. major transgenic parasites, expressing the model antigen ovalbumin (OVA), to be presented by antigen-presenting cells to OVA-specific OT-II CD4+ or OT-I CD8+ T cells. Truncated OVA was expressed in L. major as part of a secreted or nonsecreted chimeric protein with L. donovani 3′ nucleotidase (NT-OVA). Dendritic cells (DC) but not macrophages infected with L. major that secreted NT-OVA could prime OT-I T cells to proliferate and release gamma interferon. A diminished T-cell response was observed when DC were infected with parasites expressing nonsecreted NT-OVA or with heat-killed parasites. Inoculation of mice with transgenic parasites elicited the proliferation of adoptively transferred OT-I T cells and their recruitment to the site of infection in the skin. Together, these results demonstrate the possibility of targeting heterologous antigens to specific cellular compartments in L. major and suggest that proteins secreted or released by L. major in infected DC are a major source of peptides for the generation of parasite-specific CD8+ T cells. The ability of L. major transgenic parasites to activate OT-I CD8+ T cells in vivo will permit the analysis of parasite-driven T-cell expansion, differentiation, and recruitment at the clonal level. PMID:16177338

  1. 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. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Antigen-affinity controls pregerminal centser B cell selection by promoting Mcl-1 induction through BAFF receptor signaling

    NARCIS (Netherlands)

    Wensveen, Felix M.; Slinger, Erik; van Attekum, Martijn H. A.; Brink, Robert; Eldering, Eric

    2016-01-01

    Upon antigen encounter, the responsive B cell pool undergoes stringent selection which eliminates cells with low B cell receptor (BCR) affinity. Already before formation of the germinal center, activated B cells of low-affinity are negatively selected in a process that is molecularly not well

  3. Expression of 5'-nucleotidase (CD73) related to other differentiation antigens in leukemias of B-cell lineage

    NARCIS (Netherlands)

    Pieters, R.; Thompson, L. F.; Broekema, G. J.; Huismans, D. R.; Peters, G. J.; Pals, S. T.; Horst, E.; Hählen, K.; Veerman, A. J.

    1991-01-01

    Ecto-5'nucleotidase (5'NT; CD73) expression was studied with a monoclonal antibody (7G2) and a radiochemical assay and compared with the expression of other antigens in B-cell-lineage leukemias on cells from 100 leukemic patients and two cell lines. A B-cell origin was confirmed by the expression of

  4. Role of antigen in migration patterns of T cell subsets arising from gut-associated lymphoid tissue

    International Nuclear Information System (INIS)

    Dunkley, M.L.; Husband, A.J.

    1989-01-01

    Studies of the migration of antigen-specific regulatory T cell subsets responding to gut immunization were undertaken to clarify their migratory potential and the role of antigen in their localization. In initial experiments, lymphocytes collected from the thoracic duct of rats after immunization of Peyer's patches (PP) with keyhole limpet hemocyanin (KLH), were enriched for T helper (Th) cells and labelled with the fluorochrome H33342. In other experiments, a higher frequency of antigen-specific T cells was achieved by short-term culture of the enriched Th cells in the presence of KLH and the blast cells labelled with 3H-thymidine. The distribution of both populations was determined after injection into immunized and unimmunized syngeneic recipients. Whereas the uncultured population (predominantly small Th cells) localized almost exclusively in follicular lymphoid tissues, the cells expanded by secondary culture (predominantly Th blasts) appeared in the gut lamina propria (LP) initially, then in PP and mesenteric lymph nodes. The Th blasts in the LP were almost always seen in close proximity to the gut epithelium. However, the migration of neither population appeared to be influenced significantly by antigen, in contrast to previous findings with regard to IgA-committed B cells. The initial subepithelial location of Th blasts in the gut LP and their subsequent appearance in PP may provide a mechanism by which antigen presented by epithelial cells could influence B cell differentiation in PP through modulation of signals expressed by these T cells

  5. Role of antigen in migration patterns of T cell subsets arising from gut-associated lymphoid tissue

    Energy Technology Data Exchange (ETDEWEB)

    Dunkley, M.L.; Husband, A.J. (Univ. of Newcastle, N.S.W. (Australia))

    1989-07-01

    Studies of the migration of antigen-specific regulatory T cell subsets responding to gut immunization were undertaken to clarify their migratory potential and the role of antigen in their localization. In initial experiments, lymphocytes collected from the thoracic duct of rats after immunization of Peyer's patches (PP) with keyhole limpet hemocyanin (KLH), were enriched for T helper (Th) cells and labelled with the fluorochrome H33342. In other experiments, a higher frequency of antigen-specific T cells was achieved by short-term culture of the enriched Th cells in the presence of KLH and the blast cells labelled with 3H-thymidine. The distribution of both populations was determined after injection into immunized and unimmunized syngeneic recipients. Whereas the uncultured population (predominantly small Th cells) localized almost exclusively in follicular lymphoid tissues, the cells expanded by secondary culture (predominantly Th blasts) appeared in the gut lamina propria (LP) initially, then in PP and mesenteric lymph nodes. The Th blasts in the LP were almost always seen in close proximity to the gut epithelium. However, the migration of neither population appeared to be influenced significantly by antigen, in contrast to previous findings with regard to IgA-committed B cells. The initial subepithelial location of Th blasts in the gut LP and their subsequent appearance in PP may provide a mechanism by which antigen presented by epithelial cells could influence B cell differentiation in PP through modulation of signals expressed by these T cells.

  6. In vivo targeting of porcine reproductive and respiratory syndrome virus antigen through porcine DC-SIGN to dendritic cells elicits antigen-specific CD4T cell immunity in pigs.

    Science.gov (United States)

    Subramaniam, Sakthivel; Piñeyro, Pablo; Tian, Debin; Overend, Christopher; Yugo, Danielle M; Matzinger, Shannon R; Rogers, Adam J; Haac, Mary Etna R; Cao, Qian; Heffron, C Lynn; Catanzaro, Nicholas; Kenney, Scott P; Huang, Yao-Wei; Opriessnig, Tanja; Meng, Xiang-Jin

    2014-11-28

    Immunogenicity of protein subunit vaccines may be dramatically improved by targeting them through antibodies specific to c-type lectin receptors (CLRs) of dendritic cells in mice, cattle, and primates. This novel vaccine development approach has not yet been explored in pigs or other species largely due to the lack of key reagents. In this study, we demonstrate that porcine reproductive and respiratory syndrome virus (PRRSV) antigen was targeted efficiently to dendritic cells through antibodies specific to a porcine CLR molecule DC-SIGN (dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin) in pigs. A recombinant PRRSV antigen (shGP45M) was constructed by fusing secretory-competent subunits of GP4, GP5 and M proteins derived from genetically-shuffled strains of PRRSV. In vaccinated pigs, when the PRRSV shGP45M antigen was delivered through a recombinant mouse-porcine chimeric antibody specific to the porcine DC-SIGN (pDC-SIGN) neck domain, porcine dendritic cells rapidly internalized them in vitro and induced higher numbers of antigen-specific interferon-γ producing CD4T cells compared to the pigs receiving non-targeted PRRSV shGP45M antigen. The pDC-SIGN targeting of recombinant antigen subunits may serve as an alternative or complementary strategy to existing vaccines to improve protective immunity against PRRSV by inducing efficient T cell responses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Comparing Proteolytic Fingerprints of Antigen-Presenting Cells during Allergen Processing

    Directory of Open Access Journals (Sweden)

    Heidi Hofer

    2017-06-01

    Full Text Available Endolysosomal processing has a critical influence on immunogenicity as well as immune polarization of protein antigens. In industrialized countries, allergies affect around 25% of the population. For the rational design of protein-based allergy therapeutics for immunotherapy, a good knowledge of T cell-reactive regions on allergens is required. Thus, we sought to analyze endolysosomal degradation patterns of inhalant allergens. Four major allergens from ragweed, birch, as well as house dust mites were produced as recombinant proteins. Endolysosomal proteases were purified by differential centrifugation from dendritic cells, macrophages, and B cells, and combined with allergens for proteolytic processing. Thereafter, endolysosomal proteolysis was monitored by protein gel electrophoresis and mass spectrometry. We found that the overall proteolytic activity of specific endolysosomal fractions differed substantially, whereas the degradation patterns of the four model allergens obtained with the different proteases were extremely similar. Moreover, previously identified T cell epitopes were assigned to endolysosomal peptides and indeed showed a good overlap with known T cell epitopes for all four candidate allergens. Thus, we propose that the degradome assay can be used as a predictor to determine antigenic peptides as potential T cell epitopes, which will help in the rational design of protein-based allergy vaccine candidates.

  8. Segregation Lag in Polyploid Cells of the Pathogen GenusBorrelia: Implications for Antigenic Variation
.

    Science.gov (United States)

    Crowder, Christopher D; Denny, Richard L; Barbour, Alan G

    2017-06-01

    Relapsing fever agents like Borrelia hermsii undergo multiphasic antigenic variation that is attributable to spontaneous DNA non-reciprocal transpositions at a particular locus in the genome. This genetic switch results in a new protein being expressed on the cell surface, allowing cells with that phenotype to escape prevailing immunity. But the switch occurs in only one of several genomes in these spirochetes, and a newly-switched gene is effectively "recessive" until homozygosity is achieved. The longer that descendants of the switched cell expressed both old and new proteins, the longer this lineage risks neutralization by antibody to the old protein. We investigated the implications for antigenic variation of the phenotypic lag that polyploidy would confer on cells. We first experimentally determined the average genome copy number in daughter cells after division during mouse infection with B. hermsii strain HS1. We then applied discrete deterministic and stochastic simulations to predict outcomes when genomes were equably segregated either linearly, i.e. according to their position in one-dimensional arrays, or randomly partitioned, as for a sphere. Linear segregation replication provided for a lag in achievement of homozygosity that was significantly shorter than could be achieved under the random segregation condition. For cells with 16 genomes, this would be a 4-generation lag. A model incorporating the immune response and evolved matrices of switch rates indicated a greater fitness for polyploid over monoploid bacteria in terms of duration of infection.

  9. Cell-mediated immunity against human retinal extract, S-antigen, and interphotoreceptor retinoid binding protein in onchocercal chorioretinopathy

    NARCIS (Netherlands)

    van der Lelij, A.; Rothova, A.; Stilma, J. S.; Hoekzema, R.; Kijlstra, A.

    1990-01-01

    Autoimmune mechanisms are thought to be involved in the pathogenesis of onchocercal chorioretinopathy. Cell-mediated immune responses to human retinal S-antigen, interphotoreceptor retinoid binding protein (IRBP), and crude retinal extract were investigated in patients with onchocerciasis from

  10. 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

    (DC) and macrophages infiltrate the CNS during experimental autoimmune encephalomyelitis (EAE). Microglia are not considered to be as effective APC as DC or macrophages. METHODS: In this work we compared the antigen presenting capacity of CD11c+ and CD11c- microglia subsets with infiltrating CD11c......+ APC, which include DC. The microglial subpopulations (CD11c- CD45dim CD11b+ and CD11c+ CD45dim CD11b+) as well as infiltrating CD11c+ CD45high cells were sorted from CNS of C57BL/6 mice with EAE. Sorted cells were characterised by flow cytometry for surface phenotype and by quantitative real-time PCR...... 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...

  11. Interleukin-2 promotes antigenic reactivity of rested T cells but prolongs the postactivational refractory phase of activated T cells.

    Science.gov (United States)

    Norris, M S; McConnell, T J; Mannie, M D

    2001-07-10

    IL-2 is a principal autocrine growth factor that promotes T-cell activation and proliferation. However, IL-2 has also been implicated as a key intermediate in the induction and maintenance of self-tolerance in vivo. The purpose of this study was to assess whether the differential regulatory activity of IL-2 was related to the activation status of responder T cells. In cultures of rested myelin basic protein (MBP)-specific T cells, IL-2 not only induced IL-2R alpha but also augmented surface expression of several other activation-associated glycoproteins including OX40, LFA-1, B7.1, B7.2, TCR, and CD4. Pretreatment of T cells with IL-2 also up-regulated subsequent antigen reactivity in assays of MBP-stimulated proliferation and IL-2 production and also promoted proliferative responsiveness to IL-2. In cultures of activated T cells, however, IL-2 inhibited subsequent reactivity to antigen or IL-2 and thereby prolonged a phase of postactivational refractoriness. Exposure of preactivated T cells to IL-2 also inhibited subsequent responses to the mitogenic combination of PMA, ionomycin, and IL-2 without enhancing cell death. These data support the concept that the inhibitory activity of IL-2 is dependent upon the activation status of T cells and is manifest as impaired cell cycle progression in response to a variety of IL-2-dependent stimuli. Copyright 2001 Academic Press.

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

    Science.gov (United States)

    León, Beatriz; Ballesteros-Tato, André; Randall, Troy D.

    2014-01-01

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

  13. Detection of antibody activity in human sera against meningococcal cell wall antigens using a gel-immuno-radio-assay (GIRA)

    International Nuclear Information System (INIS)

    Poolman, J.T.; Zanen, H.C.

    1980-01-01

    The authors recently described the application of the SDS-polyacrylamide-gel-electrophoresis-immuno-peroxidase (SGIP) technique to the analysis of meningococcal cell walls. However, it appeared that SGIP was not sensitive enough to detect low levels of human antibodies against meningococcal cell wall antigens. They therefore replaced the peroxidase labeled anti-IgG by 125 I-labeled protein A in order to detect antibody binding by bacterial antigens separated in gels, resulting in gel-immuno-radio-assay (GIRA). (Auth.)

  14. Targeting mucosal dendritic cells with microbial antigens from probiotic lactic acid bacteria.

    Science.gov (United States)

    Mohamadzadeh, Mansour; Duong, Tri; Hoover, Timothy; Klaenhammer, Todd R

    2008-03-01

    The use of vaccines against infectious microbes has been critical to the advancement of medicine. Vaccine strategies combined with, or without, adjuvants have been established to eradicate various bacterial and viral pathogens. A new generation of vaccines is being developed using specific strains of Gram-positive, lactic acid bacteria and, notably, some probiotic lactobacilli. These bacteria have been safely consumed by humans for centuries in fermented foods. Thus, they can be orally administered, are well tolerated by recipients and could be easily and economically provided to large populations. In this overview, we focus on mucosal immunity and how its cellular component(s), particularly dendritic cells, can be specifically targeted to deliver immunogenic subunits, such as the protective antigen from Bacillus anthracis (the causative agent of anthrax). An antigen-specific immune response can be elicited using specific strains of Lactobacillus acidophilus expressing the protective antigen. A mucosal, dendritic cell-targeted approach increases the bioavailability of an immunogen of interest when delivered orally by L. acidophilus. This provides an efficiently elegant natural strategy and serves a dual function as an immune-stimulating adjuvant in vivo.

  15. HIV-specific Immunity Derived From Chimeric Antigen Receptor-engineered Stem Cells.

    Science.gov (United States)

    Zhen, Anjie; Kamata, Masakazu; Rezek, Valerie; Rick, Jonathan; Levin, Bernard; Kasparian, Saro; Chen, Irvin Sy; Yang, Otto O; Zack, Jerome A; Kitchen, Scott G

    2015-08-01

    The human immunodeficiency virus (HIV)-specific cytotoxic T lymphocyte (CTL) response is critical in controlling HIV infection. Since the immune response does not eliminate HIV, it would be beneficial to develop ways to enhance the HIV-specific CTL response to allow long-term viral suppression or clearance. Here, we report the use of a protective chimeric antigen receptor (CAR) in a hematopoietic stem/progenitor cell (HSPC)-based approach to engineer HIV immunity. We determined that CAR-modified HSPCs differentiate into functional T cells as well as natural killer (NK) cells in vivo in humanized mice and these cells are resistant to HIV infection and suppress HIV replication. These results strongly suggest that stem cell-based gene therapy with a CAR may be feasible and effective in treating chronic HIV infection and other morbidities.

  16. Role of very late antigen-1 in T-cell-mediated immunity to systemic viral infection

    DEFF Research Database (Denmark)

    Ørding Kauffmann, Susanne; Thomsen, Allan Randrup; Christensen, Jan Pravsgaard

    2006-01-01

    The T-cell response to lymphocytic choriomeningitis virus was studied in mice lacking very late antigen-1 (VLA-1). The generation of virus-specific effector T cells was unimpaired in VLA-1(-/-) mice. In the memory phase, VLA-1 deficiency did not influence the number of memory CD8(+) T cells or th......, the current findings indicate that the expression of VLA-1 is not pivotal for T-cell-mediated antiviral immunity to a systemic infection....... or their distribution between lymphoid and nonlymphoid organs. Regarding a functional role of VLA-1, we found that intracerebral infection of both VLA-1(-/-) and wild-type (wt) mice resulted in lethal T-cell-mediated meningitis, and quantitative and qualitative analyses of the cellular exudate did not reveal any...

  17. Red cell antigen prevalence predicted by molecular testing in ethnic groups of South Texas blood donors.

    Science.gov (United States)

    Aranda, Lorena I; Smith, Linda A; Jones, Scott; Beddard, Rachel

    2015-01-01

    Alloimmunization to red blood cell antigens is seen in patients receiving chronic blood transfusion. Knowing the prevalence of blood group antigens of the different ethnicities of South Texas donors can provide better management of rare blood inventory for patients in this geographical area. A total of 4369 blood donors were tested and analyzed for various antigens in the following blood group systems: ABO, Rh, Kell, Duffy, Kidd, MNS, Lutheran, Dombrock, Landsteiner-Wiener, Diego, Colton, and Scianna. Donors tested to be group 0 or A were serologically tested for the Rh (C, E, c, e) antigens. Those that tested as presumably R1R1, R2R2, or Ror were then genotyped. Donors constituted three major ethnicities: black (18.3%), Hispanic (36.3%), and Caucasian (41.1%); ethnicities comprised of Asian, American Indian, multiracial, and other accounted for the remaining donors (4.3%). The most likely common Rh phenotype for each ethnicity is as follows: black -Ror (44.4%), Hispanic -R1R1 (59.0%), and Caucasian -R1R1 (38.9%). The prevalence of Kell, Duffy, and Kidd blood group system antigens in black and Caucasian donors is comparable with published reports for the entire U.S. The black South Texas donor population had an 8.8 percent increase in prevalence of the Fy(a+b-) phenotype as compared with these published reports; the Hispanic South Texas donor population had a prevalence of 36.1 percent of the Fy(a+b-) phenotype. Regarding the Diego blood group system, the Hispanic donor population in South Texas had a prevalence of 93.5 percent for the Di(a-b+) phenotype as compared with published reports for the entire U.S. (>99.9%). The Hispanic population had a prevalence of 7.9 percent of donors testing as M-N+S-s+ as compared with 20.2 percent and 15.6 percent for black and Caucasian donors, respectively. This study helped us determine the prevalence of each of the blood group antigens in the South Texas donor population to establish and maintain adequate rare inventory of

  18. Synthetic melanin bound to subunit vaccine antigens significantly enhances CD8+ T-cell responses.

    Directory of Open Access Journals (Sweden)

    Antoine F Carpentier

    Full Text Available Cytotoxic T-lymphocytes (CTLs play a key role in immunity against cancer; however, the induction of CTL responses with currently available vaccines remains difficult. Because several reports have suggested that pigmentation and immunity might be functionally linked, we investigated whether melanin can act as an adjuvant in vaccines. Short synthetic peptides (8-35 amino acids long containing T-cell epitopes were mixed with a solution of L-Dopa, a precursor of melanin. The mixture was then oxidized to generate nanoparticles of melanin-bound peptides. Immunization with melanin-bound peptides efficiently triggered CTL responses in mice, even against self-antigens and at a very low dose of peptides (microgram range. Immunization against a tumor antigen inhibited the growth of established tumors in mice, an effect that was abrogated by the depletion of CD8+ lymphocytes. These results demonstrate the efficacy of melanin as a vaccine adjuvant.

  19. Age-Associated Decline in Thymic B Cell Expression of Aire and Aire-Dependent Self-Antigens

    Directory of Open Access Journals (Sweden)

    Sergio Cepeda

    2018-01-01

    Full Text Available Although autoimmune disorders are a significant source of morbidity and mortality in older individuals, the mechanisms governing age-associated increases in susceptibility remain incompletely understood. Central T cell tolerance is mediated through presentation of self-antigens by cells constituting the thymic microenvironment, including epithelial cells, dendritic cells, and B cells. Medullary thymic epithelial cells (mTECs and B cells express distinct cohorts of self-antigens, including tissue-restricted self-antigens (TRAs, such that developing T cells are tolerized to antigens from peripheral tissues. We find that expression of the TRA transcriptional regulator Aire, as well as Aire-dependent genes, declines with age in thymic B cells in mice and humans and that cell-intrinsic and cell-extrinsic mechanisms contribute to the diminished capacity of peripheral B cells to express Aire within the thymus. Our findings indicate that aging may diminish the ability of thymic B cells to tolerize T cells, revealing a potential mechanistic link between aging and autoimmunity.

  20. The Staphylococcus aureus Cell Wall-Anchored Protein Clumping Factor A Is an Important T Cell Antigen.

    Science.gov (United States)

    Lacey, Keenan A; Leech, John M; Lalor, Stephen J; McCormack, Niamh; Geoghegan, Joan A; McLoughlin, Rachel M

    2017-12-01

    Staphylococcus aureus has become increasingly resistant to antibiotics, and vaccines offer a potential solution to this epidemic of antimicrobial resistance. Targeting of specific T cell subsets is now considered crucial for next-generation anti- S. aureus vaccines; however, there is a paucity of information regarding T cell antigens of S. aureus This study highlights the importance of cell wall-anchored proteins as human CD4 + T cell activators capable of driving antigen-specific Th1 and Th17 cell activation. Clumping factor A (ClfA), which contains N1, N2, and N3 binding domains, was found to be a potent human T cell activator. We further investigated which subdomains of ClfA were involved in T cell activation and found that the full-length ClfA N123 and N23 were potent Th1 and Th17 activators. Interestingly, the N1 subdomain was capable of exclusively activating Th1 cells. Furthermore, when these subdomains were used in a model vaccine, N23 and N1 offered Th1- and Th17-mediated systemic protection in mice upon intraperitoneal challenge. Overall, however, full-length ClfA N123 is required for maximal protection both locally and systemically. Copyright © 2017 Lacey et al.

  1. Responses of Bovine WC1+ γδ T Cells to Protein and Nonprotein Antigens of Mycobacterium bovis

    Science.gov (United States)

    Welsh, Michael D.; Kennedy, Hilary E.; Smyth, Allister J.; Girvin, R. Martyn; Andersen, Peter; Pollock, John M.

    2002-01-01

    WC1+ γδ T cells of Mycobacterium bovis-infected cattle are highly responsive to M. bovis sonic extract (MBSE). In mycobacterial infections of other species, γδ T cells have been shown to respond to protein and nonprotein antigens, but the bovine WC1+ γδ T-cell antigenic targets within MBSE require further definition in terms of the dominance of protein versus nonprotein components. The present study sought to characterize the WC1+ γδ T-cell antigenic targets, together with the role of interleukin-2 (IL-2), in the context of M. bovis infection. This was achieved by testing crude and defined antigens to assess protein versus nonprotein recognition by WC1+ γδ T cells in comparison with CD4+ αβ T cells. Both cell types proliferated strongly in response to MBSE, with CD4+ T cells being the major producers of gamma interferon (IFN-γ). However, enzymatic digestion of the protein in MBSE removed its ability to stimulate CD4+ T-cell responses, whereas some WC1+ γδ T-cell proliferation remained. The most antigenic protein inducing proliferation and IFN-γ secretion in WC1+ γδ T-cell cultures was found to be ESAT-6, which is a potential novel diagnostic reagent and vaccine candidate. In addition, WC1+ γδ T-cell proliferation was observed in response to stimulation with prenyl pyrophosphate antigens (isopentenyl pyrophosphate and monomethyl phosphate). High levels of cellular activation (CD25 expression) resulted from MBSE stimulation of WC1+ γδ T cells from infected animals. A similar degree of activation was induced by IL-2 alone, but for WC1+ γδ T-cell division IL-2 was found to act only as a costimulatory signal, enhancing antigen-driven responses. Overall, the data indicate that protein antigens are important stimulators of WC1+ γδ T-cell proliferation and IFN-γ secretion in M. bovis infection, with nonprotein antigens inducing significant proliferation. These findings have important implications for diagnostic and vaccine development. PMID

  2. Evolution of MHC-based technologies used for detection of antigen-responsive T cells.

    Science.gov (United States)

    Bentzen, Amalie Kai; Hadrup, Sine Reker

    2017-05-01

    T cell-mediated recognition of peptide-major histocompatibility complex (pMHC) class I and II molecules is crucial for the control of intracellular pathogens and cancer, as well as for stimulation and maintenance of efficient cytotoxic responses. Such interactions may also play a role in the development of autoimmune diseases. Novel insights into this mechanism are crucial to understanding disease development and establishing new treatment strategies. MHC multimers have been used for detection of antigen-responsive T cells since the first report by Altman et al. showed that tetramerization of pMHC class I molecules provided sufficient stability to T cell receptor (TCR)-pMHC interactions, allowing detection of MHC multimer-binding T cells using flow cytometry. Since this breakthrough the scientific community has aimed for expanding the capacity of MHC multimer-based detection technologies to facilitate large-scale epitope discovery and immune monitoring in limited biological material. Screening of T cell specificity using large libraries of pMHC molecules is suitable for analyses of T cell recognition potentially at genome-wide levels rather than analyses restricted to a selection of model antigens. Such strategies provide novel insights into the immune specificities involved in disease development and response to immunotherapy, and extend fundamental knowledge related to T cell recognition patterns and cross-recognition by TCRs. MHC multimer-based technologies have now evolved from detection of 1-2 different T cell specificities per cell sample, to include more than 1000 evaluable pMHC molecules using novel technologies. Here, we provide an overview of MHC multimer-based detection technologies developed over two decades, focusing primarily on MHC class I interactions.

  3. CD4+ T-cell epitope prediction using antigen processing constraints.

    Science.gov (United States)

    Mettu, Ramgopal R; Charles, Tysheena; Landry, Samuel J

    2016-05-01

    T-cell CD4+ epitopes are important targets of immunity against infectious diseases and cancer. State-of-the-art methods for MHC class II epitope prediction rely on supervised learning methods in which an implicit or explicit model of sequence specificity is constructed using a training set of peptides with experimentally tested MHC class II binding affinity. In this paper we present a novel method for CD4+ T-cell eptitope prediction based on modeling antigen-processing constraints. Previous work indicates that dominant CD4+ T-cell epitopes tend to occur adjacent to sites of initial proteolytic cleavage. Given an antigen with known three-dimensional structure, our algorithm first aggregates four types of conformational stability data in order to construct a profile of stability that allows us to identify regions of the protein that are most accessible to proteolysis. Using this profile, we then construct a profile of epitope likelihood based on the pattern of transitions from unstable to stable regions. We validate our method using 35 datasets of experimentally measured CD4+ T cell responses of mice bearing I-Ab or HLA-DR4 alleles as well as of human subjects. Overall, our results show that antigen processing constraints provide a significant source of predictive power. For epitope prediction in single-allele systems, our approach can be combined with sequence-based methods, or used in instances where little or no training data is available. In multiple-allele systems, sequence-based methods can only be used if the allele distribution of a population is known. In contrast, our approach does not make use of MHC binding prediction, and is thus agnostic to MHC class II genotypes. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Identification of Bacterial Surface Antigens by Screening Peptide Phage Libraries Using Whole Bacteria Cell-Purified Antisera

    Science.gov (United States)

    Hu, Yun-Fei; Zhao, Dun; Yu, Xing-Long; Hu, Yu-Li; Li, Run-Cheng; Ge, Meng; Xu, Tian-Qi; Liu, Xiao-Bo; Liao, Hua-Yuan

    2017-01-01

    Bacterial surface proteins can be good vaccine candidates. In the present study, we used polyclonal antibodies purified with intact Erysipelothrix rhusiopthiae to screen phage-displayed random dodecapeptide and loop-constrained heptapeptide libraries, which led to the identification of mimotopes. Homology search of the mimotope sequences against E. rhusiopthiae-encoded ORF sequences revealed 14 new antigens that may localize on the surface of E. rhusiopthiae. When these putative surface proteins were used to immunize mice, 9/11 antigens induced protective immunity. Thus, we have demonstrated that a combination of using the whole bacterial cells to purify antibodies and using the phage-displayed peptide libraries to determine the antigen specificities of the antibodies can lead to the discovery of novel bacterial surface antigens. This can be a general approach for identifying surface antigens for other bacterial species. PMID:28184219

  5. Highly efficient gene transfer using a retroviral vector into murine T cells for preclinical chimeric antigen receptor-expressing T cell therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kusabuka, Hotaka; Fujiwara, Kento; Tokunaga, Yusuke; Hirobe, Sachiko; Nakagawa, Shinsaku, E-mail: nakagawa@phs.osaka-u.ac.jp; Okada, Naoki, E-mail: okada@phs.osaka-u.ac.jp

    2016-04-22

    Adoptive immunotherapy using chimeric antigen receptor-expressing T (CAR-T) cells has attracted attention as an efficacious strategy for cancer treatment. To prove the efficacy and safety of CAR-T cell therapy, the elucidation of immunological mechanisms underlying it in mice is required. Although a retroviral vector (Rv) is mainly used for the introduction of CAR to murine T cells, gene transduction efficiency is generally less than 50%. The low transduction efficiency causes poor precision in the functional analysis of CAR-T cells. We attempted to improve the Rv gene transduction protocol to more efficiently generate functional CAR-T cells by optimizing the period of pre-cultivation and antibody stimulation. In the improved protocol, gene transduction efficiency to murine T cells was more than 90%. In addition, almost all of the prepared murine T cells expressed CAR after puromycin selection. These CAR-T cells had antigen-specific cytotoxic activity and secreted multiple cytokines by antigen stimulation. We believe that our optimized gene transduction protocol for murine T cells contributes to the advancement of T cell biology and development of immunotherapy using genetically engineered T cells. - Highlights: • We established highly efficient gene transduction protocols for murine T cells. • CD8{sup +} CAR-T cells had antigen-specific cytotoxic activity. • CD4{sup +} CAR-T cells secreted multiple cytokines by antigen stimulation. • This finding can contribute to the development of T-cell biology and immunotherapy.

  6. Highly efficient gene transfer using a retroviral vector into murine T cells for preclinical chimeric antigen receptor-expressing T cell therapy

    International Nuclear Information System (INIS)

    Kusabuka, Hotaka; Fujiwara, Kento; Tokunaga, Yusuke; Hirobe, Sachiko; Nakagawa, Shinsaku; Okada, Naoki

    2016-01-01

    Adoptive immunotherapy using chimeric antigen receptor-expressing T (CAR-T) cells has attracted attention as an efficacious strategy for cancer treatment. To prove the efficacy and safety of CAR-T cell therapy, the elucidation of immunological mechanisms underlying it in mice is required. Although a retroviral vector (Rv) is mainly used for the introduction of CAR to murine T cells, gene transduction efficiency is generally less than 50%. The low transduction efficiency causes poor precision in the functional analysis of CAR-T cells. We attempted to improve the Rv gene transduction protocol to more efficiently generate functional CAR-T cells by optimizing the period of pre-cultivation and antibody stimulation. In the improved protocol, gene transduction efficiency to murine T cells was more than 90%. In addition, almost all of the prepared murine T cells expressed CAR after puromycin selection. These CAR-T cells had antigen-specific cytotoxic activity and secreted multiple cytokines by antigen stimulation. We believe that our optimized gene transduction protocol for murine T cells contributes to the advancement of T cell biology and development of immunotherapy using genetically engineered T cells. - Highlights: • We established highly efficient gene transduction protocols for murine T cells. • CD8 + CAR-T cells had antigen-specific cytotoxic activity. • CD4 + CAR-T cells secreted multiple cytokines by antigen stimulation. • This finding can contribute to the development of T-cell biology and immunotherapy.

  7. Novel fusion proteins for the antigen-specific staining and elimination of B cell receptor-positive cell populations demonstrated by a tetanus toxoid fragment C (TTC) model antigen.

    Science.gov (United States)

    Klose, Diana; Saunders, Ute; Barth, Stefan; Fischer, Rainer; Jacobi, Annett Marita; Nachreiner, Thomas

    2016-02-17

    In an earlier study we developed a unique strategy allowing us to specifically eliminate antigen-specific murine B cells via their distinct B cell receptors using a new class of fusion proteins. In the present work we elaborated our idea to demonstrate the feasibility of specifically addressing and eliminating human memory B cells. The present study reveals efficient adaptation of the general approach to selectively target and eradicate human memory B cells. In order to demonstrate the feasibility we engineered a fusion protein following the principle of recombinant immunotoxins by combining a model antigen (tetanus toxoid fragment C, TTC) for B cell receptor targeting and a truncated version of Pseudomonas aeruginosa exotoxin A (ETA') to induce apoptosis after cellular uptake. The TTC-ETA' fusion protein not only selectively bound to a TTC-reactive murine B cell hybridoma cell line in vitro but also to freshly isolated human memory B cells from immunized donors ex vivo. Specific toxicity was confirmed on an antigen-specific population of human CD27(+) memory B cells. This protein engineering strategy can be used as a generalized platform approach for the construction of therapeutic fusion proteins with disease-relevant antigens as B cell receptor-binding domains, offering a promising approach for the specific depletion of autoreactive B-lymphocytes in B cell-driven autoimmune diseases.

  8. Antigenic protein synthesis of Campylobacter jejuni in contact with chicken cells

    DEFF Research Database (Denmark)

    Vegge, Christina Skovgaard; Bang, Dang D.; Li, Yiping

    to the environment of the avian gastrointestinal tract. Consequently, the most important reservoir for C. jejuni is the gut of chickens, which are colonized efficiently without causing disease in the birds. Upon co-cultivation with mammalian cells, C. jejuni secrete specific Cia proteins, which are required...... the synthesis of antigenic C. jejuni proteins upon cultivation with chicken cells. Two strains of C. jejuni (the human isolate NCTC11168 and the chicken isolate DVI-SC11) were incubated with primary intestinal chicken cells and subsequently used to raise antisera in rabbits. Negative controls were carried out...... in parallel. These antisera were tested by Western blotting against C. jejuni total protein as well as periplasmic-, surface- and extracellular protein fractions. A unique antibody reaction was discovered to a protein from samples, which had been cultivated with chicken cells. The identity of this protein...

  9. Chimeric antigen receptors for adoptive T cell therapy in acute myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Mingxue Fan

    2017-08-01

    Full Text Available Abstract Currently, conventional therapies for acute myeloid leukemia (AML have high failure and relapse rates. Thus, developing new strategies is crucial for improving the treatment of AML. With the clinical success of anti-CD19 chimeric antigen receptor (CAR T cell therapies against B-lineage malignancies, many studies have attempted to translate the success of CAR T cell therapy to other malignancies, including AML. This review summarizes the current advances in CAR T cell therapy against AML, including preclinical studies and clinical trials, and discusses the potential AML-associated surface markers that could be used for further CAR technology. Finally, we describe strategies that might address the current issues of employing CAR T cell therapy in AML.

  10. Identification of Mycobacterium bovis antigens by analysis of bovine T-cell responses after infection with a virulent strain

    Directory of Open Access Journals (Sweden)

    Alito A.

    2003-01-01

    Full Text Available Purification and characterization of individual antigenic proteins are essential for the understanding of the pathogenic mechanisms of mycobacteria and the immune response against them. In the present study, we used anion-exchange chromatography to fractionate cell extracts and culture supernatant proteins from Mycobacterium bovis to identify T-cell-stimulating antigens. These fractions were incubated with peripheral blood mononuclear cells (PBMC from M. bovis-infected cattle in lymphoproliferation assays. This procedure does not denature proteins and permits the testing of mixtures of potential antigens that could be later identified. We characterized protein fractions with high stimulation indices from both culture supernatants and cell extracts. Proteins were identified by two-dimensional gel electrophoresis followed by N-terminal sequencing or MALDI-TOF. Culture supernatant fractions containing low molecular weight proteins such as ESAT6 and CFP10 and other proteins (85B, MPB70, and the novel antigens TPX and TRB-B were associated with a high stimulation index. These results reinforce the concept that some low molecular weight proteins such as ESAT6 and CFP10 play an important role in immune responses. Also, Rv3747 and L7/L12 were identified in high stimulation index cell extract fractions. These data show that protein fractions with high lymphoproliferative activity for bovine PBMC can be characterized and antigens which have been already described and new protein antigens can also be identified in these fractions.

  11. 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.

  12. Engineering tolerance using biomaterials to target and control antigen presenting cells.

    Science.gov (United States)

    Tostanoski, Lisa H; Gosselin, Emily A; Jewell, Christopher M

    2016-05-01

    Autoimmune diseases occur when cells of the adaptive immune system incorrectly recognize and attack "self" tissues. Importantly, the proliferation and differentiation of these cells is triggered and controlled by interactions with antigen presenting cells (APCs), such as dendritic cells. Thus, modulating the signals transduced by APCs (e.g., cytokines, costimulatory surface proteins) has emerged as a promising strategy to promote tolerance for diseases such as multiple sclerosis, type 1 diabetes, and lupus. However, many approaches have been hindered by non-specific activity of immunosuppressive or immunoregulatory cues, following systemic administration of soluble factors via traditional injections routes (e.g., subcutaneous, intravenous). Biomaterials offer a unique opportunity to control the delivery of tolerogenic signals in vivo via properties such as controlled particle size, tunable release kinetics, and co-delivery of multiple classes of cargo. In this review, we highlight recent reports that exploit these properties of biomaterials to target APCs and promote tolerance via three strategies, i) passive or active targeting of particulate carriers to APCs, ii) biomaterial-mediated control over antigen localization and processing, and iii) targeted delivery of encapsulated or adsorbed immunomodulatory signals. These reports represent exciting advances toward the goal of more effective therapies for autoimmune diseases, without the broad suppressive effects associated with current clinically-approved therapies.

  13. T-cell responses against Malaria: Effect of parasite antigen diversity and relevance for vaccine development.

    Science.gov (United States)

    Nlinwe, Omarine Nfor; Kusi, Kwadwo Asamoah; Adu, Bright; Sedegah, Martha

    2018-03-21

    The on-going agenda for global malaria elimination will require the development of additional disease control and prevention measures since currently available tools are showing signs of inadequacy. Malaria vaccines are seen as one such important addition to the control arsenal since vaccines have proven to be highly effective public health tools against important human diseases. Both cell-mediated and antibody responses are generally believed to be important for malaria parasite control, although the exact targets of T and B cell responses against malaria have not been clearly defined. However, our current understanding of the immune response to malaria suggests that T cell responses against multiple antigenic targets may potentially be key for the development of a highly efficacious malaria vaccine. This review takes a comprehensive look at the available literature on T cell-mediated immunity against all human stages of the malaria parasite and the effect of antigen diversity on these responses. The implications of these interrelationships for the development of an effective vaccine for malaria are also highlighted. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Oral delivery of human biopharmaceuticals, autoantigens and vaccine antigens bioencapsulated in plant cells.

    Science.gov (United States)

    Kwon, Kwang-Chul; Verma, Dheeraj; Singh, Nameirakpam D; Herzog, Roland; Daniell, Henry

    2013-06-15

    Among 12billion injections administered annually, unsafe delivery leads to >20million infections and >100million reactions. In an emerging new concept, freeze-dried plant cells (lettuce) expressing vaccine antigens/biopharmaceuticals are protected in the stomach from acids/enzymes but are released to the immune or blood circulatory system when plant cell walls are digested by microbes that colonize the gut. Vaccine antigens bioencapsulated in plant cells upon oral delivery after priming, conferred both mucosal and systemic immunity and protection against bacterial, viral or protozoan pathogens or toxin challenge. Oral delivery of autoantigens was effective against complications of type 1 diabetes and hemophilia, by developing tolerance. Oral delivery of proinsulin or exendin-4 expressed in plant cells regulated blood glucose levels similar to injections. Therefore, this new platform offers a low cost alternative to deliver different therapeutic proteins to combat infectious or inherited diseases by eliminating inactivated pathogens, expensive purification, cold storage/transportation and sterile injections. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Application of Adoptive T-Cell Therapy Using Tumor Antigen-Specific T-Cell Receptor Gene Transfer for the Treatment of Human Leukemia

    Directory of Open Access Journals (Sweden)

    Toshiki Ochi

    2010-01-01

    Full Text Available The last decade has seen great strides in the field of cancer immunotherapy, especially the treatment of melanoma. Beginning with the identification of cancer antigens, followed by the clinical application of anti-cancer peptide vaccination, it has now been proven that adoptive T-cell therapy (ACT using cancer antigen-specific T cells is the most effective option. Despite the apparent clinical efficacy of ACT, the timely preparation of a sufficient number of cancer antigen-specific T cells for each patient has been recognized as its biggest limitation. Currently, therefore, attention is being focused on ACT with engineered T cells produced using cancer antigen-specific T-cell receptor (TCR gene transfer. With regard to human leukemia, ACT using engineered T cells bearing the leukemia antigen-specific TCR gene still remains in its infancy. However, several reports have provided preclinical data on TCR gene transfer using Wilms' tumor gene product 1 (WT1, and also preclinical and clinical data on TCR gene transfer involving minor histocompatibility antigen, both of which have been suggested to provide additional clinical benefit. In this review, we examine the current status of anti-leukemia ACT with engineered T cells carrying the leukemia antigen-specific TCR gene, and discuss the existing barriers to progress in this area.

  16. Cellular Immune Responses for Squamous Cell Carcinoma Antigen Recognized by T Cells 3 in Patients with Hepatocellular Carcinoma.

    Directory of Open Access Journals (Sweden)

    Kiichiro Kaji

    Full Text Available Squamous cell carcinoma antigen recognized by T cells 3 (SART3, a tumor-associated antigen expressed in many cancers, functions in tumor rejection. In this study, we investigated its usefulness as an immunotherapeutic target in hepatocellular carcinoma (HCC.The expression of SART3 in hepatoma cell lines and HCC tissues was investigated by immunofluorescence and immunohistochemical analyses. Two peptides derived from SART3 (SART3109 and SART3315 were used for immunological analysis. T-cell responses were investigated by interferon-gamma (IFN-γ enzyme-linked immunospot and cytotoxic T lymphocyte (CTL assays using peripheral blood mononuclear cells (PBMCs in 47 patients, and tumor-infiltrating lymphocytes in 8 of 47 patients with HCC. The safety of immunotherapy using a SART3-derived peptide was investigated by vaccinations of SART3109 in 12 patients with HCC (trial registration: UMIN000005677.The immunofluorescence and immunohistochemical analyses showed that SART3 was expressed in six HCC cell lines, and in HCC tissues including of alpha-fetoprotein-negative individuals. SART3-specific CTLs were generated by stimulating PBMCs with the peptides, and they showed cytotoxicity against HCC cells expressing the protein. Of the 47 HCC patients, 25.5% and 10.6% showed significant responses to SART3109 and SART3315, respectively. The infiltration of SART3109-specific IFN-γ-producing CTLs into the tumor site was confirmed. In the vaccination study, no severe adverse events were observed, and the peptide-specific CTLs were newly induced in four of five patients tested.SART3 is an immunotherapeutic candidate, and peptides from this antigen may be applied in HCC immunotherapy.UMIN000005677.

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

    Science.gov (United States)

    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; Zhao, Yangbing; Kalos, Michael; Milone, Michael C; June, Carl H

    2015-04-01

    This study compared second-generation chimeric antigen receptors (CAR) encoding signaling domains composed of CD28, ICOS, and 4-1BB (TNFRSF9). Here, we report that certain CARs endow T cells with the ability to undergo long-term autonomous proliferation. Transduction of primary human T cells with lentiviral vectors encoding some of the CARs resulted in sustained proliferation for up to 3 months following a single stimulation through the T-cell receptor (TCR). Sustained numeric expansion was independent of cognate antigen and did not require the addition of exogenous cytokines or feeder cells after a single stimulation of the TCR and CD28. Results from gene array and functional assays linked sustained cytokine secretion and expression of T-bet (TBX21), EOMES, and GATA-3 to the effect. Sustained expression of the endogenous IL2 locus has not been reported in primary T cells. Sustained proliferation was dependent on CAR structure and high expression, the latter of which was necessary but not sufficient. The mechanism involves constitutive signaling through NF-κB, AKT, ERK, and NFAT. The propagated CAR T cells retained a diverse TCR repertoire, and cellular transformation was not observed. The CARs with a constitutive growth phenotype displayed inferior antitumor effects and engraftment in vivo. Therefore, the design of CARs that have a nonconstitutive growth phenotype may be a strategy to improve efficacy and engraftment of CAR T cells. The identification of CARs that confer constitutive or nonconstitutive growth patterns may explain observations that CAR T cells have differential survival patterns in clinical trials. ©2015 American Association for Cancer Research.

  18. Loss of Proliferation and Antigen Presentation Activity following Internalization of Polydispersed Carbon Nanotubes by Primary Lung Epithelial Cells

    Science.gov (United States)

    Kumari, Mandavi; Sachar, Sumedha; Saxena, Rajiv K.

    2012-01-01

    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. PMID:22384094

  19. High expression of carcinoembryonic antigen-related cell adhesion molecule (CEACAM) 6 and 8 in primary myelofibrosis

    DEFF Research Database (Denmark)

    Riley, Caroline Hasselbalch; Skov, Vibe; Larsen, Thomas Stauffer

    2011-01-01

    for the egress of CD34+ cells from the bone marrow. Carcinoembryonic antigen-related cell adhesion molecule (CEACAM) 6 has been implicated in cell adhesion, cellular invasiveness, angiogenesis, and inflammation, which are all key processes in the pathophysiology of PMF. Accordingly, CEACAMs may play an important...

  20. Uptake of synthetic naked RNA by skin-resident dendritic cells via macropinocytosis allows antigen expression and induction of T-cell responses in mice.

    Science.gov (United States)

    Selmi, Abderraouf; Vascotto, Fulvia; Kautz-Neu, Kordula; Türeci, Özlem; Sahin, Ugur; von Stebut, Esther; Diken, Mustafa; Kreiter, Sebastian

    2016-09-01

    Intradermal administration of antigen-encoding RNA has entered clinical testing for cancer vaccination. However, insight into the underlying mechanism of RNA uptake, translation and antigen presentation is still limited. Utilizing pharmacologically optimized naked RNA, the dose-response kinetics revealed a rise in reporter signal with increasing RNA amounts and a prolonged RNA translation of reporter protein up to 30 days after intradermal injection. Dendritic cells (DCs) in the dermis were shown to engulf RNA, and the signal arising from the reporter RNA was significantly diminished after DC depletion. Macropinocytosis was relevant for intradermal RNA uptake and translation in vitro and in vivo. By combining intradermal RNA vaccination and inhibition of macropinocytosis, we show that effective priming of antigen-specific CD8(+) T-cells also relies on this uptake mechanism. This report demonstrates that direct antigen translation by dermal DCs after intradermal naked RNA vaccination is relevant for efficient priming of antigen-specific T-cells.

  1. Comparison of monocyte-derived dendritic cells from colorectal cancer patients, non-small-cell-lung-cancer patients and healthy donors

    DEFF Research Database (Denmark)

    Kvistborg, P; Bechmann, C M; Pedersen, A W

    2009-01-01

    Dendritic cells (DCs) are bone marrow-derived professional antigen presenting cells. Due to their role as potent inducers of immune responses, these cells are widely used as adjuvant in experimental clinical settings for cancer immune therapy. We have developed a DC-based vaccine using autologous...... blood monocytes loaded with allogeneic tumor cell lysate rich in cancer/testis antigens. This vaccine has at present been tested for activity in three phase II clinical trials including two cohorts of patients with advanced colorectal cancer (CRC) and one cohort of patients with advanced non-small-cell...

  2. Role of sustained antigen release from nanoparticle vaccines in shaping the T cell memory phenotype.

    Science.gov (United States)

    Demento, Stacey L; Cui, Weiguo; Criscione, Jason M; Stern, Eric; Tulipan, Jacob; Kaech, Susan M; Fahmy, Tarek M

    2012-06-01

    Particulate vaccines are emerging promising technologies for the creation of tunable prophylactics against a wide variety of conditions. Vesicular and solid biodegradable polymer platforms, exemplified by liposomes and polyesters, respectively, are two of the most ubiquitous platforms in vaccine delivery studies. Here we directly compared the efficacy of each in a long-term immunization study and in protection against a model bacterial antigen. Immunization with poly(lactide-co-glycolide) (PLGA) nanoparticles elicited prolonged antibody titers compared to liposomes and alum. The magnitude of the cellular immune response was also highest in mice vaccinated with PLGA, which also showed a higher frequency of effector-like memory T cell phenotype, leading to an effective clearance of intracellular bacteria. The difference in performance of these two common particulate platforms is shown not to be due to material differences but appears to be connected to the kinetics of antigen delivery. Thus, this study highlights the importance of sustained antigen release mediated by particulate platforms and its role in the long-term appearance of effector memory cellular response. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Co-culture with podoplanin+ cells protects leukemic blast cells with leukemia-associated antigens in the tumor microenvironment.

    Science.gov (United States)

    Lee, Ji Yoon; Han, A-Reum; Lee, Sung-Eun; Min, Woo-Sung; Kim, Hee-Je

    2016-05-01

    Podoplanin+ cells are indispensable in the tumor microenvironment. Increasing evidence suggests that podoplanin may support the growth and metastasis of solid tumors; however, to the best of our knowledge no studies have determined whether or not podoplanin serves a supportive role in acute myeloid leukemia (AML). The effects of co‑culture with podoplanin+ cells on the cellular activities of the leukemic cells, such as apoptosis and cell proliferation, in addition to the expression of podoplanin in leukemic cells, were investigated. Due to the fact that genetic abnormalities are the primary cause of leukemogenesis, the overexpression of the fibromyalgia‑like tyrosine kinase‑3 gene in colony forming units was also examined following cell sorting. Podoplanin+ cells were found to play a protective role against apoptosis in leukemic cells and to promote cell proliferation. Tumor‑associated antigens, including Wilms' tumor gene 1 and survivin, were increased when leukemic cells were co‑cultured with podoplanin+ cells. In combination, the present results also suggest that podoplanin+ cells can function as stromal cells for blast cell retention in the AML tumor microenvironment.

  4. Identification of Anti-tumor Cells Carrying Natural Killer (NK Cell Antigens in Patients With Hematological Cancers

    Directory of Open Access Journals (Sweden)

    Ewelina Krzywinska

    2015-10-01

    Full Text Available Natural killer (NK cells, a cytotoxic lymphocyte lineage, are able to kill tumor cells in vitro and in mouse models. However, whether these cells display an anti-tumor activity in cancer patients has not been demonstrated. Here we have addressed this issue in patients with several hematological cancers. We found a population of highly activated CD56dimCD16+ NK cells that have recently degranulated, evidence of killing activity, and it is absent in healthy donors. A high percentage of these cells expressed natural killer cell p46-related protein (NKp46, natural-killer group 2, member D (NKG2D and killer inhibitory receptors (KIRs and a low percentage expressed NKG2A and CD94. They are also characterized by a high metabolic activity and active proliferation. Notably, we found that activated NK cells from hematological cancer patients have non-NK tumor cell antigens on their surface, evidence of trogocytosis during tumor cell killing. Finally, we found that these activated NK cells are distinguished by their CD45RA+RO+ phenotype, as opposed to non-activated cells in patients or in healthy donors displaying a CD45RA+RO− phenotype similar to naïve T cells. In summary, we show that CD45RA+RO+ cells, which resemble a unique NK population, have recognized tumor cells and degranulate in patients with hematological neoplasias.

  5. Chimeric antigen receptor T cells for the treatment of cancer and the future of preclinical models for predicting their toxicities.

    Science.gov (United States)

    Wegner, Anja

    2017-06-01

    Chimeric antigen receptor T-cell therapy has achieved highly promising results in clinical trials, particularly in B-cell malignancies. However, reports of serious adverse events including a number of patient deaths have raised concerns about safety of this treatment. Presently available preclinical models are not designed for predicting toxicities seen in human patients. Besides choosing the right animal model, careful considerations must be taken in chimeric antigen receptor T-cell design and the amount of T cells infused. The development of more sophisticated in vitro models and humanized mouse models for preclinical modeling and toxicity tests will help us to improve the design of clinical trials in cancer immunotherapy.

  6. Antigen-specific IgA B memory cell responses to Shigella antigens elicited in volunteers immunized with live attenuated Shigella flexneri 2a oral vaccine candidates.

    Science.gov (United States)

    Simon, J K; Maciel, M; Weld, E D; Wahid, R; Pasetti, M F; Picking, W L; Kotloff, K L; Levine, M M; Sztein, M B

    2011-05-01

    We studied the induction of antigen-specific IgA memory B cells (B(M)) in volunteers who received live attenuated Shigella flexneri 2a vaccines. Subjects ingested a single oral dose of 10(7), 10(8) or 10(9) CFU of S. flexneri 2a with deletions in guaBA (CVD 1204) or in guaBA, set and sen (CVD 1208). Antigen-specific serum and stool antibody responses to LPS and Ipa B were measured on days 0, 7, 14, 28 and 42. IgA B(M) cells specific to LPS, Ipa B and total IgA were assessed on days 0 and 28. We show the induction of significant LPS-specific IgA B(M) cells in anti-LPS IgA seroresponders. Positive correlations were found between anti-LPS IgA B(M) cells and anti-LPS IgA in serum and stool; IgA B(M) cell responses to IpaB were also observed. These B(M) cell responses are likely play an important role in modulating the magnitude and longevity of the humoral response. Copyright © 2011 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    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; Zhao, Yangbing; Kalos, Michael; Milone, Michael C.; June, Carl H.

    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 did not require the addition of exogenous cytokines or feeder cells after a single stimulation of the TCR and CD28. Results from gene array and functional assays linked sustained cytokine secretion and expression of T-bet, EOMES and GATA-3 to the effect. Sustained expression of the endogenous IL2 locus has not been reported in primary T cells. Sustained proliferation was dependent on CAR structure and high expression, the latter of which was necessary but not sufficient. The mechanism involves constitutive signaling through NF-kB, Akt, Erk and NFAT. The propagated CAR T cells retained a diverse TCR repertoire and cellular transformation was not observed. The CARs with a constitutive growth phenotype displayed inferior antitumor effects and engraftment in vivo. Therefore the design of CARs that have a non-constitutive growth phenotype may be a strategy to improve efficacy and engraftment of CAR T cells. The identification of CARs that confer constitutive or non-constitutive growth patterns may explain observations that CAR T cells have differential survival patterns in clinical trials. PMID:25600436

  8. Antigen and Memory CD8 T Cells: Were They Both Right?

    Directory of Open Access Journals (Sweden)

    Epelman Slava

    2007-06-01

    Full Text Available Picture yourself as a researcher in immunology. To begin your project, you ask a question: Do CD8 T cells require antigen to maintain a memory response? This question is of prime importance to numerous medical fields. In chronologic order, you digest the literature, but unfortunately, you hit a major stumbling block in the 1990s. The crux of the problem is that which so often happens in science: two well-recognized, capable groups emerge with diametrically opposed conclusions, leaving you pondering which set of wellcontrolled data to believe. Fortunately, years later, a surprising group of articles sheds light on this mystery and subtly reconciles these two positions.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    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...

  10. Localization of human immunodeficiency virus antigens in infected cells by scanning/transmission-immunogold techniques

    International Nuclear Information System (INIS)

    Herrera, M.I.; Santa Maria, I.; de Andres, R.; Najera, R.

    1988-01-01

    An application of high resolution scanning/transmission electron microscopy (STEM) and gold-labelling techniques for the rapid detection of human immunodeficiency virus (HIV) in infected cells has been developed. Experimental in vitro studies for detecting two HIV structural proteins, gp41 and p17, were performed following an indirect labeling procedure that uses monoclonal anti-p17 and anti-gp41 antibodies as primary antibodies and 40 nm gold-linked goat antimouse IgG as secondary antibodies. The cells were then studied by STEM in the scanning mode. Unambiguous localization of the viral antigens was possible by combining the three-dimensional image provided by the secondary electron image and the atomic number-dependent backscattered electron image for the identification of the gold marker. This technique combines both the morphological information and the rapid procedures of scanning electron microscopy with the precise and sensitive antigen detection provided by the use of STEM and immunological methods. The preliminary results of its application to the study of peripheral blood mononuclear cells from four anti-HIV-seropositive patients showing the presence of specific labeling in all of them suggest that it might prove useful for early detection of HIV infection before seroconversion, as well as for quantitative studies

  11. Squamous Cell Carcinoma Antigen 2 (SCCA2, SERPINB4: An Emerging Biomarker for Skin Inflammatory Diseases

    Directory of Open Access Journals (Sweden)

    Kenji Izuhara

    2018-04-01

    Full Text Available Squamous cell carcinoma antigens 1 and 2 (SCCA1 and 2, SERPIN B3 and B4, members of the ovalbumin serpin (ov-serpin/clade B serpin family, were originally discovered as tumor-specific antigens and are used as tumor markers for various kinds of squamous cell carcinomas. Recently, our understanding of the underlying mechanisms of how SCCA1/2 enhance tumor growth has greatly increased. Moreover, it has been shown that SCCA1/2 are involved in the pathogenesis of several inflammatory diseases: asthma, psoriasis, and atopic dermatitis (AD. IL-22 and IL-17, signature cytokines of type 17 inflammation, as well as IL-4 and IL-13, signature cytokines of type 2 inflammation, both of which are positively correlated with the pathogenesis of psoriasis and allergic diseases, respectively, can induce expression of SCCA1/2 in airway epithelial cells and/or keratinocytes, leading to high expression of SCCA1/2 in these diseases. Based on these findings, several trials have been performed to examine the potential of applying SCCA1/2 to biomarkers for these diseases. The findings show that SCCA2 is useful to aid diagnosis, estimate clinical severity and disease type, and assess responses to treatment in psoriasis and AD. These results suggest that SCCA2 has emerged as a novel biomarker for skin inflammatory diseases.

  12. T cell activation. II. Activation of human T lymphoma cells by cross-linking of their MHC class I antigens

    DEFF Research Database (Denmark)

    Dissing, S; Geisler, C; Rubin, B

    1990-01-01

    The present work demonstrates that antibody-induced cross-linking of MHC class I antigens on Jurkat T lymphoma cells leads to a rise in intracellular calcium (Cai2+) and, in the presence of phorbol ester (PMA), to IL-2 production and IL-2 receptor expression. The rise in Cai2+ exhibited a profile...... very different from that obtained after anti-CD3 antibody-induced activation suggesting that activation signals are transduced differently after binding of anti-CD3 antibody and class I cross-linking, respectively. However, when Cai2+ was examined in individual Jurkat cells by means of a digital image...

  13. Assay of endotoxin by limulus amebocyte lysate.

    Science.gov (United States)

    Ketchum, P A; Novitsky, T J

    2000-01-01

    Horseshoe crabs fight off infectious agents with a complex array of proteins present in amebocytes, the major cell type in their hemolymph. These amebocytes contain both large and small granules (1). When exposed to bacteria or other infectious agents the amebocytes release proteins into their surroundings by exocytosis. The small granules of Limulus amebocytes contain antibacterial proteins, including polyphemusins and the big defensins (2). The large granules contain the Limulus anti-lipopolysaccharide factor (LALF) and the clot-forming group of serine protease zymogens. Exocytosis is initiated by the reaction of amebocytes with lipopolysaccharide (LPS) from Gram-negative bacteria or other microbial components. LPS is also called endotoxin because it is found in the outer membrane of the gram-negative bacterial cell wall. A solid clot forms in response to the lipid A portion of LPS, thereby walling off the infection site or preventing the loss of blood when the animal is damaged physically (3).

  14. The Fas/CD95 receptor regulates the death of autoreactive B cells and the selection of antigen-specific B cells

    Directory of Open Access Journals (Sweden)

    Anne-Odile eHUEBER

    2012-07-01

    Full Text Available Cell death receptors have crucial roles in the regulation of immune responses. Here we review recent in vivo data confirming that the Fas death receptor (TNFSR6 on B cells is important for the regulation of autoimmunity since the impairment of only Fas function on B cells results in uncontrolled autoantibody production and autoimmunity. Fas plays a role in the elimination of the non-specific and auto-reactive B cells in germinal center, while during the selection of antigen specific B cells different escape signals ensure the resistance to Fas-mediated apoptosis. Antigen specific survival such as BCR or MHCII signal or coreceptors (CD19 cooperating with BCR inhibits the formation of death inducing signaling complex. Antigen-specific survival can be reinforced by antigen-independent signals of IL4 or CD40 overproducing the anti-apoptotic members of the Bcl-2 family proteins.

  15. Recognition of nonpeptide antigens by human V gamma 9V delta 2 T cells requires contact with cells of human origin.

    Science.gov (United States)

    Green, A E; Lissina, A; Hutchinson, S L; Hewitt, R E; Temple, B; James, D; Boulter, J M; Price, D A; Sewell, A K

    2004-06-01

    SUMMARY It is becoming apparent that gamma delta T cells form an important part of the adaptive immune response. However, the ligands recognized by gamma delta T cell receptors (TCRs) and the exact biological function of the cells that express this receptor remain unclear. Numerous studies have shown that the dominant human peripheral blood subset of gamma delta T cells, which express a V gamma 9V delta 2 TCR, can activate in response to low molecular weight nonpeptidic molecules. Some of these components have been purified from bacteria or parasites. We examined the activation of polyclonal gamma delta T cell lines, clones with V gamma 9V delta 2 and V gamma 9V delta 1 TCRs, and gamma delta T cells directly ex vivo in response to multiple phosphate, alkylamine and aminobisphosphonate (nBP) antigens and purified protein derivative from Mycobacterium tuberculosis (PPD). V gamma 9V delta 2 T cells were able to respond to multiple small organic molecules of highly variable structure whereas cells expressing a similar V gamma 9 chain paired with a V delta 1 chain failed to recognize these antigens. Thus, the TCR delta chain appears to make an important contribution to the recognition of these antigens. The kinetics of responses to alkylphosphate and alkylamine antigens differ from those of responses to the nBP pamidronate. These different classes of antigen are believed to have differed mechanisms of action. Such differences explain why nBPs can be pulsed onto antigen presenting cells (APCs) and still retain their ability to activate gamma delta T cells while alkylphosphate and alkylamine antigens cannot. We also demonstrate that a substantial proportion of the cells that produce IFN gamma directly ex vivo in response to PPD are gamma delta T cells and that gamma delta T cell activation requires contact with cells of human origin.

  16. Adoptive Immunotherapy for Hematological Malignancies Using T Cells Gene-Modified to Express Tumor Antigen-Specific Receptors

    Directory of Open Access Journals (Sweden)

    Hiroshi Fujiwara

    2014-12-01

    Full Text Available Accumulating clinical evidence suggests that adoptive T-cell immunotherapy could be a promising option for control of cancer; evident examples include the graft-vs-leukemia effect mediated by donor lymphocyte infusion (DLI and therapeutic infusion of ex vivo-expanded tumor-infiltrating lymphocytes (TIL for melanoma. Currently, along with advances in synthetic immunology, gene-modified T cells retargeted to defined tumor antigens have been introduced as “cellular drugs”. As the functional properties of the adoptive immune response mediated by T lymphocytes are decisively regulated by their T-cell receptors (TCRs, transfer of genes encoding target antigen-specific receptors should enable polyclonal T cells to be uniformly redirected toward cancer cells. Clinically, anticancer adoptive immunotherapy using genetically engineered T cells has an impressive track record. Notable examples include the dramatic benefit of chimeric antigen receptor (CAR gene-modified T cells redirected towards CD19 in patients with B-cell malignancy, and the encouraging results obtained with TCR gene-modified T cells redirected towards NY-ESO-1, a cancer-testis antigen, in patients with advanced melanoma and synovial cell sarcoma. This article overviews the current status of this treatment option, and discusses challenging issues that still restrain the full effectiveness of this strategy, especially in the context of hematological malignancy.

  17. Kinetics of antigen specific and non-specific polyclonal B-cell responses during lethal Plasmodium yoelii malaria

    Directory of Open Access Journals (Sweden)

    Laurence Rolland

    1992-06-01

    Full Text Available In order to study the kinetics and composition of the polyclonal B-cell activation associated to malaria infection, antigen-specific and non-specific B-cell responses were evaluated in the spleens of mice infected with Plasmodium yoelii 17 XL or injected with lysed erythrocytes or plasma from P. yoelii infected mice or with P. falciparum culture supernatants. Spleen/body weigth ratio, numbers of nucleated spleen cells and Immunoglobulin-containing and Immunoglobulin-secreting cells increased progressively during the course of infection,in parallel to the parasitemia. A different pattern of kinetics was observed when anti-sheep red blood cell and anti-trinitrophenylated-sheep red blood cell plaque forming cells response were studied: maximum values were observed at early stages of infection, whereas the number of total Immunoglobulin-containing and Immunoglobulin-secreting cells were not yet altered. Conversely, at the end of infection, when these latter values reached their maximum, the anti-sheep red blood cell and anti-trinitrophenylated-sheep red blood cell specific responses were normal or even infranormal. In mice injected with Plasmodium-derived material, a higher increase in antigen-specific PFC was observed, as compared to the increase of Immunoglobulin-containing and Immunoglobulin-secreting cell numbers. This suggested a "preferential" (antigen-plus mitogen-induced stimulation of antigen-specific cells rather than a generalized non-specific (mitogen-induced triggering of B-lymphocytes. On the basis of these and previous results, it is suggested that polyclonal B-cell activation that takes place during the course of infection appears as a result of successive waves of antigen-specific B-cell activation.

  18. Incorporation of a hinge domain improves the expansion of chimeric antigen receptor T cells

    Directory of Open Access Journals (Sweden)

    Le Qin

    2017-03-01

    Full Text Available Abstract Background Multiple iterations of chimeric antigen receptors (CARs have been developed, mainly focusing on intracellular signaling modules. However, the effect of non-signaling extracellular modules on the expansion and therapeutic efficacy of CARs remains largely undefined. Methods We generated two versions of CAR vectors, with or without a hinge domain, targeting CD19, mesothelin, PSCA, MUC1, and HER2, respectively. Then, we systematically compared the effect of the hinge domains on the growth kinetics, cytokine production, and cytotoxicity of CAR T cells in vitro and in vivo. Results During in vitro culture period, the percentages and absolute numbers of T cells expressing the CARs containing a hinge domain continuously increased, mainly through the promotion of CD4+ CAR T cell expansion, regardless of the single-chain variable fragment (scFv. In vitro migration assay showed that the hinges enhanced CAR T cells migratory capacity. The T cells expressing anti-CD19 CARs with or without a hinge had similar antitumor capacities in vivo, whereas the T cells expressing anti-mesothelin CARs containing a hinge domain showed enhanced antitumor activities. Conclusions Hence, our results demonstrate that a hinge contributes to CAR T cell expansion and is capable of increasing the antitumor efficacy of some specific CAR T cells. Our results suggest potential novel strategies in CAR vector design.

  19. Cognate antigen stimulation generates potent CD8+ inflammatory effector T cells.

    Directory of Open Access Journals (Sweden)

    Hsueh-Cheng eSung

    2013-12-01

    Full Text Available Inflammatory reactions are believed to be triggered by innate signals and have a major protective role by recruiting innate immunity cells, favoring lymphocyte activation and differentiation, and thus contributing to the sequestration and elimination of the injurious stimuli. Although certain lymphocyte types such as TH17 cells co-participate in inflammatory reactions, their generation from the naïve pool requires the pre-existence of an inflammatory milieu. In this context, inflammation is always regarded as beginning with an innate response that may be eventually perpetuated and amplified by certain lymphocyte types. In contrast, we here show that even in sterile immunizations or in MyD88 deficient mice, CD8 T cells produce a burst of pro-inflammatory cytokines and chemokines. These functions follow opposite rules to the classic CD8 effector functions since they are generated prior to cell expansion and decline before antigen elimination. As few as 56 CD8+ inflammatory effector cells in a lymph node can mobilize 107 cells in 24h, including lymphocytes, natural killer cells and several accessory cell types involved in inflammatory reactions. Thus, although inflammation modulates cognate responses, CD8 cognate responses also initiate local inflammatory reactions.

  20. The athymic nude rat. Immunobiological characteristics with special reference to establishment of non-antigen-specific T-cell reactivity and induction of antigen-specific immunity

    DEFF Research Database (Denmark)

    Hougen, H P

    1991-01-01

    The aim of the present review has been to describe some immunobiological characteristics of the athymic nude rat and on the basis of these to describe the possibilities of establishing non-antigen-specific T-cell reactivity and inducing antigen-specific immunity. After a brief introduction, some...... general characteristics of the autosomal recessive rnu/rnu rat are outlined. This athymic mutant normally has a longer lifespan than athymic nude mice and is easier to breed. Inbred nude rats are now available with several rat strain backgrounds. Since the rnu/rnu rat is athymic, the morphology...... are mentioned and their possible function outlined. However, thymic hormones still do not play an important role in immunotherapy. There are some striking differences in the morphology of lymphatic tissues of athymic and euthymic rats. The thymic area in nude rats consists only of fat and clusters of epithelial...

  1. Repopulated antigen presenting cells induced an imbalanced differentiation of the helper T cells in whole body gamma irradiated mice

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hae Ran; Jo, Sung Kee [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Paik, Sang Kee [Chungnam National University, Taejon (Korea, Republic of)

    2004-07-01

    Therapeutic irradiation of cancer patients, although it may be protected by several antioxidant agents against free radicals, often induces chronic sequelae such as inflammation (allergic inflammation). This is a limiting factor for radiotherapy. Following radiotherapy, the inflammation or injury can occur in any organ with a high radiosensitivity such as the lung, bladder, kidney, liver, stomach and intestine. The mechanism by which ionizing radiation initiates inflammation is, however, poorly understood. In recent studies, it was suggested that a factor for irradiation-induced inflammation might be the over production of IL-4 that enhances fibroblast proliferation and collagen synthesis. During the early stages after irradiation, type 2 of the helper T cells might be the major source of IL-4, and later on there seems to be an activation of the other IL-4 producing cell types, e.q. macrophages or mast cells. This is interesting because inflammation is classically seen to be dominated by Th1 cells secreting IFN-{gamma}. In the previous study, we were interested in the enhancement of the IL-4 and the IgE production during the development of immune cells after {gamma}-irradiation. We were able to deduce that IL-4 production was increased because of the shifted differentiation of the naive Th cells by the repopulated antigen presenting cells after irradiation. The aim of the present study was to precisely define whether antigen-presenting cells (APCs) of whole body irradiation-treated mice could influence the shifted differentiation of the Th cells. This view can be demonstrated by confirming that the shifted functional status of the Th cells is induced by the altered function of the repopulated macrophages after whole body irradiation (WBI)

  2. Different Ia antigen characterization between granulocyte progenitor cells (CFC-G) and monocyte-macrophage progenitor cells (CFC-M).

    Science.gov (United States)

    Numata, M; Koizumi, S; Horita, S; Ueno, Y; Yamagami, M; Taniguchi, N

    1985-09-01

    Ia-like antigen-positive (Ia+) and -negative (Ia-) cell populations were separated from human cord blood cells and bone marrow mononuclear cells by a rosette technique with a combined use of staphylococcal protein-A-coated bovine red blood cells and the monoclonal OKIa 1 antibody, or by using a cell-sorting technique. Colony-forming units-granulocytes-monocytes-macrophages (GFU-GM) were assayed in a semisolid agar culture, and colony-forming cells-granulocytes (CFC-G) were differentiated from colony-forming cells-monocytes-macrophages (CFC-M) by double staining for esterase activity. The majority of CFC-G in cord blood was grown in the Ia+ fraction; Ia+ CFC-G/Ia- CFC-G = 1.62 +/- 0.34 (mean +/- SD), which was similar to the ratio in bone marrow (Ia+/Ia- = 1.80 +/- 0.37). In contrast, the majority of CFC-M in cord blood was grown in the Ia- fraction; Ia+/Ia- for CFC-M = 0.50 +/- 0.09. The predominance of CFC-G in the Ia+ fraction in contrast to predominance of CFC-M in the Ia- fraction was confirmed by using a cell-sorting technique. T-lymphocyte depletion and the culture supernatants of Ia+ and Ia- cells did not affect differentiation of CFC-G and CFC-M. These data suggest that there are potent differences in the expression of Ia-like antigens between CFC-G and CFC-M, indicating that the Ia+ progenitor cell population generates predominantly CFC-G, whereas the Ia- population generates mainly CFC-M during the maturation process in granulopoiesis.

  3. VSTM-v1, a potential myeloid differentiation antigen that is downregulated in bone marrow cells from myeloid leukemia patients

    OpenAIRE

    Xie, Min; Li, Ting; Li, Ning; Li, Jinlan; Yao, Qiumei; Han, Wenling; Ruan, Guorui

    2015-01-01

    Leukocyte differentiation antigens often represent important markers for the diagnosis, classification, prognosis, and therapeutic targeting of myeloid leukemia. Herein, we report a potential leukocyte differentiation antigen gene VSTM1 (V-set and transmembrane domain-containing 1) that was downregulated in bone marrow cells from leukemia patients and exhibited a higher degree of promoter methylation. The expression level of its predominant encoded product, VSTM1-v1, was positively correlated...

  4. Pooled human platelet lysate versus fetal bovine serum—investigating the proliferation rate, chromosome stability and angiogenic potential of human adipose tissue-derived stem cells intended for clinical use

    DEFF Research Database (Denmark)

    Trojahn Kølle, Stig-Frederik; Oliveri, Roberto S; Glovinski, Peter V

    2013-01-01

    Because of an increasing focus on the use of adipose-derived stem cells (ASCs) in clinical trials, the culture conditions for these cells are being optimized. We compared the proliferation rates and chromosomal stability of ASCs that had been cultured in Dulbecco's modified Eagle's Medium (DMEM...

  5. Changes in lamina propria dendritic cells on the oral administration of exogenous protein antigens during weaning.

    Science.gov (United States)

    Ohue, Ryuji; Nakamoto, Masahiro; Kitabatake, Naofumi; Tani, Fumito

    2012-05-01

    Two critical periods of maximum exposure to antigens occur in young mammals, immediately after birth and at weaning, as a result of colonization by commensal bacteria and the ingestion of new diets. At weaning, active immune responses of antibody production against dietary proteins are known to occur, but simultaneously, oral tolerance is acquired for harmless food proteins. However, regulated mechanisms of the immune system at weaning remain to be elucidated although its immune responses may be somewhat similar to those in adulthood. Considering that tolerogenic antigen-presenting cells (APCs) are likely to be a key factor in the acquisition of oral tolerance, in the present study, we examined the changes of dendritic cells (DCs) in the lamina propria (LP) on exposure to food proteins at weaning. C57BL/6 female mice were weaned at the age of 3 weeks and orally administered 10 mg of ovalbumin (OVA) for ten consecutive days after weaning. The administration led to a decrease in the plasma level of immunoglobulin specific for OVA, suggesting the acquisition of oral tolerance. The uptake of fluorescence-labeled OVA was significantly observed for CD11c(+)LPDCs. When we analyzed the changes of two types of LPDCs, PDCA-1(+) MHC II(+) DCs and CD103(+) MHC II(+) DCs, ten consecutive gavages of OVA marginally, but not significantly, augmented only the frequency of PDCA-1(+) MHC II(+) DCs. Considering that the change of APCs likely appears immediately on the response to antigen intake, we found the statistically significant increase in the frequency of PDCA-1(+) DCs, but not in that of CD103(+) DCs, even after two treatments, indicating PDCA-1(+) DCs to be recruited in the LP within 2 days of exposure to food proteins. These results suggest that the behavior of tolerogenic PDCA-1(+) DCs may change at weaning with the removal of the immunoprotective components of maternal milk.

  6. Cis-acting pathways selectively enforce the non-immunogenicity of shed placental antigen for maternal CD8 T cells.