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Sample records for antigen-specific polyclonal cytotoxic

  1. Antigen-Specific Polyclonal Cytotoxic T Lymphocytes Induced by Fusions of Dendritic Cells and Tumor Cells

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    Shigeo Koido

    2010-01-01

    Full Text Available The aim of cancer vaccines is induction of tumor-specific cytotoxic T lymphocytes (CTLs that can reduce the tumor mass. Dendritic cells (DCs are potent antigen-presenting cells and play a central role in the initiation and regulation of primary immune responses. Thus, DCs-based vaccination represents a potentially powerful strategy for induction of antigen-specific CTLs. Fusions of DCs and whole tumor cells represent an alternative approach to deliver, process, and subsequently present a broad spectrum of antigens, including those known and unidentified, in the context of costimulatory molecules. Once DCs/tumor fusions have been infused back into patient, they migrate to secondary lymphoid organs, where the generation of antigen-specific polyclonal CTL responses occurs. We will discuss perspectives for future development of DCs/tumor fusions for CTL induction.

  2. Allopurinol reduces antigen-specific and polyclonal activation of human T cells

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    Damián ePérez-Mazliah

    2012-09-01

    Full Text Available Allopurinol is the most popular commercially available xanthine oxidase inhibitor and it is widely used for treatment of symptomatic hyperuricaemia, or gout. Although, several anti-inflammatory actions of allopurinol have been demonstrated in vivo and in vitro, there have been few studies on the action of allopurinol on T cells. In the current study, we have assessed the effect of allopurinol on antigen-specific and mitogen-driven activation and cytokine production in human T cells. Allopurinol markedly decreased the frequency of IFN-γ and IL-2-producing T cells, either after polyclonal or antigen-specific stimulation with Herpes Simplex virus 1, Influenza virus, tetanus toxoid and Trypanosoma cruzi-derived antigens. Allopurinol attenuated CD69 upregulation after CD3 and CD28 engagement and significantly reduced the levels of spontaneous and mitogen-induced intracellular reactive oxygen species in T cells. The diminished T cell activation and cytokine production in the presence of allopurinol support a direct action of allopurinol on human T cells, offering a potential pharmacological tool for the management of cell-mediated inflammatory diseases.

  3. Kinetics of antigen specific and non-specific polyclonal B-cell responses during lethal Plasmodium yoelii malaria

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    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.

  4. Antigen-specific cytotoxic T cell and antigen-specific proliferating T cell clones can be induced to cytolytic activity by monoclonal antibodies against T3

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    Spits, H.; Yssel, H.; Leeuwenberg, J.; de Vries, J. E.

    1985-01-01

    T3 is a human differentiation antigen expressed exclusively on mature T cells. In this study it is shown that anti-T3 monoclonal antibodies, in addition to their capacity to induce T cells to proliferate, are able to induce antigen-specific cytotoxic T lymphocyte clones to mediate antigen

  5. Visualization of antigen-specific human cytotoxic T lymphocytes labeled with superparamagnetic iron-oxide particles

    Energy Technology Data Exchange (ETDEWEB)

    Beer, Ambros J. [Technical University of Munich (TUM), Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Holzapfel, Konstantin; Settles, Marcus; Rummeny, Ernst J. [Technical University of Munich, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Neudorfer, Juliana; Kroenig, Holger; Peschel, Christian; Bernhard, Helga [TUM, Munich, Department of Hematology/Oncology, Klinikum rechts der Isar, Munich (Germany); Piontek, Guido; Schlegel, Juergen [TUM, Munich, Division of Neuropathology, Institute of Pathology, Klinikum rechts der Isar, Munich (Germany)

    2008-06-15

    New technologies are needed to characterize the migration and survival of antigen-specific T cells in vivo. In this study, we developed a novel technique for the labeling of human cytotoxic T lymphocytes with superparamagnetic iron-oxide particles and the subsequent depiction with a conventional 1.5-T magnetic resonance scanner. Antigen-specific CD8{sup +} T lymphocytes were labeled with ferucarbotran by lipofection. The uptake of ferucarbotran was confirmed by immunofluorescence microscopy using a dextran-specific antibody, and the intracellular enrichment of iron was measured by atomic absorption spectrometry. The imaging of T cells was performed by magnetic resonance on day 0, 2, 7 and 14 after the labeling procedure. On day 0 and 2 post labeling, a pronounced shortening of T2*-relaxation times was observed, which diminished after 7 days and was not detectable anymore after 14 days, probably due to the retained mitotic activity of the labeled T cells. Of importance, the antigen-specific cytolytic activity of the T cells was preserved following ferucarbotran labeling. Efficient ferucarbotran labeling of functionally active T lymphocytes and their detection by magnetic resonance imaging allows the in vivo monitoring of T cells and, subsequently, will impact the further development of T cell-based therapies. (orig.)

  6. Visualization of antigen-specific human cytotoxic T lymphocytes labeled with superparamagnetic iron-oxide particles

    International Nuclear Information System (INIS)

    Beer, Ambros J.; Holzapfel, Konstantin; Settles, Marcus; Rummeny, Ernst J.; Neudorfer, Juliana; Kroenig, Holger; Peschel, Christian; Bernhard, Helga; Piontek, Guido; Schlegel, Juergen

    2008-01-01

    New technologies are needed to characterize the migration and survival of antigen-specific T cells in vivo. In this study, we developed a novel technique for the labeling of human cytotoxic T lymphocytes with superparamagnetic iron-oxide particles and the subsequent depiction with a conventional 1.5-T magnetic resonance scanner. Antigen-specific CD8 + T lymphocytes were labeled with ferucarbotran by lipofection. The uptake of ferucarbotran was confirmed by immunofluorescence microscopy using a dextran-specific antibody, and the intracellular enrichment of iron was measured by atomic absorption spectrometry. The imaging of T cells was performed by magnetic resonance on day 0, 2, 7 and 14 after the labeling procedure. On day 0 and 2 post labeling, a pronounced shortening of T2*-relaxation times was observed, which diminished after 7 days and was not detectable anymore after 14 days, probably due to the retained mitotic activity of the labeled T cells. Of importance, the antigen-specific cytolytic activity of the T cells was preserved following ferucarbotran labeling. Efficient ferucarbotran labeling of functionally active T lymphocytes and their detection by magnetic resonance imaging allows the in vivo monitoring of T cells and, subsequently, will impact the further development of T cell-based therapies. (orig.)

  7. Increasing a Robust Antigen-Specific Cytotoxic T Lymphocyte Response by FMDV DNA Vaccination with IL-9 Expressing Construct

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    Qiang Zou

    2010-01-01

    Full Text Available Various chemokines and cytokines as adjuvants can be used to improve efficacy of DNA vaccination. In this study, we sought to investigate if a DNA construct expressing IL-9 (designed as proV-IL9 as a molecular adjuvant enhance antigen specific immune responses elicited by the pcD-VP1 DNA vaccination. Mice immunized with pcD-VP1 combined with proV-IL9 developed a strong humoral response. In addition, the coinoculation induced significant higher level of antigen-specific cell proliferation and cytotoxic response. This agreed well with higher expression level of IFN-γ and perforin in CD8+ T cells, but not with IL-17 in these T cells. The results indicate that IL-9 induces the development of IFN-γ-producing CD8+ T cells (Tc1, but not the IL-17-producing CD8+ T cells (Tc17. Up-regulated expressions of BCL-2 and BCL-XL were exhibited in these Tc1 cells, suggesting that IL-9 may trigger antiapoptosis mechanism in these cells. Together, these results demonstrated that IL-9 used as molecular adjuvant could enhance the immunogenicity of DNA vaccination, in augmenting humoral and cellular responses and particularly promoting Tc1 activations. Thus, the IL-9 may be utilized as a potent Tc1 adjuvant for DNA vaccines.

  8. T Helper 17 Promotes Induction of Antigen-Specific Gut-Mucosal Cytotoxic T Lymphocytes following Adenovirus Vector Vaccination

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    Masahisa Hemmi

    2017-11-01

    Full Text Available Few current vaccines can establish antigen (Ag-specific immune responses in both mucosal and systemic compartments. Therefore, development of vaccines providing defense against diverse infectious agents in both compartments is of high priority in global health. Intramuscular vaccination of an adenovirus vector (Adv has been shown to induce Ag-specific cytotoxic T lymphocytes (CTLs in both systemic and gut-mucosal compartments. We previously found that type I interferon (IFN signaling is required for induction of gut-mucosal, but not systemic, CTLs following vaccination; however, the molecular mechanism involving type I IFN signaling remains unknown. Here, we found that T helper 17 (Th17-polarizing cytokine expression was down-regulated in the inguinal lymph nodes (iLNs of Ifnar2−/− mice, resulting in the reduction of Ag-specific Th17 cells in the iLNs and gut mucosa of the mice. We also found that prior transfer of Th17 cells reversed the decrease in the number of Ag-specific gut-mucosal CTLs in Ifnar2−/− mice following Adv vaccination. Additionally, prior transfer of Th17 cells into wild-type mice enhanced the induction of Ag-specific CTLs in the gut mucosa, but not in systemic compartments, suggesting a gut mucosa-specific mechanism where Th17 cells regulate the magnitude of vaccine-elicited Ag-specific CTL responses. These data suggest that Th17 cells translate systemic type I IFN signaling into a gut-mucosal CTL response following vaccination, which could promote the development of promising Adv vaccines capable of establishing both systemic and gut-mucosal protective immunity.

  9. Tracking in vivo migration and distribution of antigen-specific cytotoxic T lymphocytes by 5,6-carboxyfluorescein diacetate succinimidyl ester staining during cancer immunotherapy.

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    Xu, Wei-li; Li, Suo-lin; Wen, Ming; Wen, Jun-ye; Han, Jie; Zhang, Hong-zhen; Gao, Fei; Cai, Jian-hui

    2013-08-01

    Killing of targeted tumors during adoptive cell transfer therapy is associated with cytotoxic T lymphocyte (CTL) numbers, immunophenotype, tumor-specificity, and in vivo residence time, migration, and distribution. Therefore, tracing in vivo persistence, migration, and distribution of CTLs is important for cancer immunotherapy. Optimal staining concentration for CTL proliferation was determined by cell counting kit-8 (CCK-8) assay and killing efficiencies of CTLs or carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled melanoma antigen-specific cytotoxic T lymphocytes (CFSE-CTLs) for malignant melanoma cells in vitro were compared. Additionally, CFSE-CTLs were intravenously transfused to mice receiving B16 melanoma, and their residence time, migration, and distribution in vivo were observed by measuring fluorescence intensities of CFSE-CTLs per gram of tissue (%FI/g) in various tissues and analyzing tumor/non-tumor (T/NT) values. Anti-tumor effects of transferred CTLs and correlation between %FI/g and D-value of tumor size were analyzed. Five-micromolar CFSE was optimal for labeling CTLs with minimal cytotoxicity. No significant difference occurred between CTLs and CFSE-CTLs for tumor cell killing (P = 0.849) or interleukin-2 (P = 0.318) and interferon-γ (P = 0.201) levels. Distribution of CTLs in vivo varied with time. A negative correlation between %FI/g in tumors and D-value of tumor sizes by Spearman correlation analysis was observed. CTLs were recruited to and killed tumors from 6 hours to 3 days after cell infusion. CTLs were observed up to three weeks later in the tumor, liver, kidneys, and spleen; this was related to the abundant blood supply or the nature of immune organs. CCK-8 assay is a novel method to select optimal CFSE staining concentrations. Fluorescence intensity of transferred CTLs reflects their killing efficiency of tumors. CFSE fluorescent markers can trace in vivo CTL persistence, migration, and distribution because of its stability

  10. Antigen-specific primed cytotoxic T cells eliminate tumour cells in vivo and prevent tumour development, regardless of the presence of anti-apoptotic mutations conferring drug resistance.

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    Jaime-Sánchez, Paula; Catalán, Elena; Uranga-Murillo, Iratxe; Aguiló, Nacho; Santiago, Llipsy; M Lanuza, Pilar; de Miguel, Diego; A Arias, Maykel; Pardo, Julián

    2018-05-09

    Cytotoxic CD8 + T (Tc) cells are the main executors of transformed and cancer cells during cancer immunotherapy. The latest clinical results evidence a high efficacy of novel immunotherapy agents that modulate Tc cell activity against bad prognosis cancers. However, it has not been determined yet whether the efficacy of these treatments can be affected by selection of tumoural cells with mutations in the cell death machinery, known to promote drug resistance and cancer recurrence. Here, using a model of prophylactic tumour vaccination based on the LCMV-gp33 antigen and the mouse EL4 T lymphoma, we analysed the molecular mechanism employed by Tc cells to eliminate cancer cells in vivo and the impact of mutations in the apoptotic machinery on tumour development. First of all, we found that Tc cells, and perf and gzmB are required to efficiently eliminate EL4.gp33 cells after LCMV immunisation during short-term assays (1-4 h), and to prevent tumour development in the long term. Furthermore, we show that antigen-pulsed chemoresistant EL4 cells overexpressing Bcl-X L or a dominant negative form of caspase-3 are specifically eliminated from the peritoneum of infected animals, as fast as parental EL4 cells. Notably, antigen-specific Tc cells control the tumour growth of the mutated cells, as efficiently as in the case of parental cells. Altogether, expression of the anti-apoptotic mutations does not confer any advantage for tumour cells neither in the short-term survival nor in long-term tumour formation. Although the mechanism involved in the elimination of the apoptosis-resistant tumour cells is not completely elucidated, neither necroptosis nor pyroptosis seem to be involved. Our results provide the first experimental proof that chemoresistant cancer cells with mutations in the main cell death pathways are efficiently eliminated by Ag-specific Tc cells in vivo during immunotherapy and, thus, provide the molecular basis to treat chemoresistant cancer cells with CD8 Tc

  11. Human Tregs Made Antigen Specific by Gene Modification: The Power to Treat Autoimmunity and Antidrug Antibodies with Precision

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    Patrick R. Adair

    2017-09-01

    Full Text Available Human regulatory CD4+ T cells (Tregs are potent immunosuppressive lymphocytes responsible for immune tolerance and homeostasis. Since the seminal reports identifying Tregs, vast research has been channeled into understanding their genesis, signature molecular markers, mechanisms of suppression, and role in disease. This research has opened the doors for Tregs as a potential therapeutic for diseases and disorders such as multiple sclerosis, type I diabetes, transplantation, and immune responses to protein therapeutics, like factor VIII. Seminal clinical trials have used polyclonal Tregs, but the frequency of antigen-specific Tregs among polyclonal populations is low, and polyclonal Tregs may risk non-specific immunosuppression. Antigen-specific Treg therapy, which uses genetically modified Tregs expressing receptors specific for target antigens, greatly mitigates this risk. Building on the principles of T-cell receptor cloning, chimeric antigen receptors (CARs, and a novel CAR derivative, called B-cell antibody receptors, our lab has developed different types of antigen-specific Tregs. This review discusses the current research and optimization of gene-modified antigen-specific human Tregs in our lab in several disease models. The preparations and considerations for clinical use of such Tregs also are discussed.

  12. Rapid production of antigen-specific monoclonal antibodies from a variety of animals

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    Kurosawa Nobuyuki

    2012-09-01

    Full Text Available Abstract Background Although a variety of animals have been used to produce polyclonal antibodies against antigens, the production of antigen-specific monoclonal antibodies from animals remains challenging. Results We propose a simple and rapid strategy to produce monoclonal antibodies from a variety of animals. By staining lymph node cells with an antibody against immunoglobulin and a fluorescent dye specific for the endoplasmic reticulum, plasma/plasmablast cells were identified without using a series of antibodies against lineage markers. By using a fluorescently labeled antigen as a tag for a complementary cell surface immunoglobulin, antigen-specific plasma/plasmablast cells were sorted from the rest of the cell population by fluorescence-activated cell sorting. Amplification of cognate pairs of immunoglobulin heavy and light chain genes followed by DNA transfection into 293FT cells resulted in the highly efficient production of antigen-specific monoclonal antibodies from a variety of immunized animals. Conclusions Our technology eliminates the need for both cell propagation and screening processes, offering a significant advantage over hybridoma and display strategies.

  13. Screening Immunomodulators To Skew the Antigen-Specific Autoimmune Response.

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    Northrup, Laura; Sullivan, Bradley P; Hartwell, Brittany L; Garza, Aaron; Berkland, Cory

    2017-01-03

    Current therapies to treat autoimmune diseases often result in side effects such as nonspecific immunosuppression. Therapies that can induce antigen-specific immune tolerance provide an opportunity to reverse autoimmunity and mitigate the risks associated with global immunosuppression. In an effort to induce antigen-specific immune tolerance, co-administration of immunomodulators with autoantigens has been investigated in an effort to reprogram autoimmunity. To date, identifying immunomodulators that may skew the antigen-specific immune response has been ad hoc at best. To address this need, we utilized splenocytes obtained from mice with experimental autoimmune encephalomyelitis (EAE) in order to determine if certain immunomodulators may induce markers of immune tolerance following antigen rechallenge. Of the immunomodulatory compounds investigated, only dexamethasone modified the antigen-specific immune response by skewing the cytokine response and decreasing T-cell populations at a concentration corresponding to a relevant in vivo dose. Thus, antigen-educated EAE splenocytes provide an ex vivo screen for investigating compounds capable of skewing the antigen-specific immune response, and this approach could be extrapolated to antigen-educated cells from other diseases or human tissues.

  14. A novel dendritic cell-based direct ex vivo assay for detection and enumeration of circulating antigen-specific human T cells.

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    Carrio, Roberto; Zhang, Ge; Drake, Donald R; Schanen, Brian C

    2018-05-07

    Although a variety of assays have been used to examine T cell responses in vitro, standardized ex vivo detection of antigen-specific CD4 + T cells from human circulatory PBMCs remains constrained by low-dimensional characterization outputs and the need for polyclonal, mitogen-induced expansion methods to generate detectable response signals. To overcome these limitations, we developed a novel methodology utilizing antigen-pulsed autologous human dendritic target cells in a rapid and sensitive assay to accurately enumerate antigen-specific CD4 + T cell precursor frequency by multiparametric flow cytometry. With this approach, we demonstrate the ability to reproducibly quantitate poly-functional T cell responses following both primary and recall antigenic stimulation. Furthermore, this approach enables more comprehensive phenotypic profiling of circulating antigen-specific CD4 + T cells, providing valuable insights into the pre-existing polarization of antigen-specific T cells in humans. Combined, this approach permits sensitive and detailed ex vivo detection of antigen-specific CD4 + T cells delivering an important tool for advancing vaccine, immune-oncology and other therapeutic studies.

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

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

    2003-01-01

    Background: Soybean protein is used in a number of food products but unfortunately is also a common cause of food allergy. Upon ingestion of soy protein, healthy mice like other animals and humans generate a soy-specific antibody response in the absence of signs of illness. Not much is known about...... the relationship between the immunogenic proteins involved in this nondeleterious antibody response and the pathological response associated with food allergy. The objective of the present study was to characterize the antigenic specificity of the soy protein-specific antibody response generated in healthy mice...... ingesting soy protein. Methods: Blood from mice fed a soy-containing diet was analyzed using ELISA and immunoblot for antibody reactivity towards various soy protein fractions and pure soy proteins/subunits. Mice bred on a soy-free diet were used as controls. Results: The detectable antigenic specificity...

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

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

    2012-01-01

    Tumor-infiltrating lymphocytes (TIL) isolated from melanoma patients and expanded in vitro by interleukin (IL)-2 treatment can elicit therapeutic response after adoptive transfer, but the antigen specificities of the T cells transferred have not been determined. By compiling all known melanoma-as...... from different fragments of resected melanoma lesions. In summary, our findings provide an initial definition of T-cell populations contributing to tumor recognition in TILs although the specificity of many tumor-reactive TILs remains undefined....

  17. Rapid profiling of the antigen regions recognized by serum antibodies using massively parallel sequencing of antigen-specific libraries.

    KAUST Repository

    Domina, Maria; Lanza Cariccio, Veronica; Benfatto, Salvatore; D'Aliberti, Deborah; Venza, Mario; Borgogni, Erica; Castellino, Flora; Biondo, Carmelo; D'Andrea, Daniel; Grassi, Luigi; Tramontano, Anna; Teti, Giuseppe; Felici, Franco; Beninati, Concetta

    2014-01-01

    There is a need for techniques capable of identifying the antigenic epitopes targeted by polyclonal antibody responses during deliberate or natural immunization. Although successful, traditional phage library screening is laborious and can map only some of the epitopes. To accelerate and improve epitope identification, we have employed massive sequencing of phage-displayed antigen-specific libraries using the Illumina MiSeq platform. This enabled us to precisely identify the regions of a model antigen, the meningococcal NadA virulence factor, targeted by serum antibodies in vaccinated individuals and to rank hundreds of antigenic fragments according to their immunoreactivity. We found that next generation sequencing can significantly empower the analysis of antigen-specific libraries by allowing simultaneous processing of dozens of library/serum combinations in less than two days, including the time required for antibody-mediated library selection. Moreover, compared with traditional plaque picking, the new technology (named Phage-based Representation OF Immuno-Ligand Epitope Repertoire or PROFILER) provides superior resolution in epitope identification. PROFILER seems ideally suited to streamline and guide rational antigen design, adjuvant selection, and quality control of newly produced vaccines. Furthermore, this method is also susceptible to find important applications in other fields covered by traditional quantitative serology.

  18. Rapid profiling of the antigen regions recognized by serum antibodies using massively parallel sequencing of antigen-specific libraries.

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    Maria Domina

    Full Text Available There is a need for techniques capable of identifying the antigenic epitopes targeted by polyclonal antibody responses during deliberate or natural immunization. Although successful, traditional phage library screening is laborious and can map only some of the epitopes. To accelerate and improve epitope identification, we have employed massive sequencing of phage-displayed antigen-specific libraries using the Illumina MiSeq platform. This enabled us to precisely identify the regions of a model antigen, the meningococcal NadA virulence factor, targeted by serum antibodies in vaccinated individuals and to rank hundreds of antigenic fragments according to their immunoreactivity. We found that next generation sequencing can significantly empower the analysis of antigen-specific libraries by allowing simultaneous processing of dozens of library/serum combinations in less than two days, including the time required for antibody-mediated library selection. Moreover, compared with traditional plaque picking, the new technology (named Phage-based Representation OF Immuno-Ligand Epitope Repertoire or PROFILER provides superior resolution in epitope identification. PROFILER seems ideally suited to streamline and guide rational antigen design, adjuvant selection, and quality control of newly produced vaccines. Furthermore, this method is also susceptible to find important applications in other fields covered by traditional quantitative serology.

  19. Rapid profiling of the antigen regions recognized by serum antibodies using massively parallel sequencing of antigen-specific libraries.

    KAUST Repository

    Domina, Maria

    2014-12-04

    There is a need for techniques capable of identifying the antigenic epitopes targeted by polyclonal antibody responses during deliberate or natural immunization. Although successful, traditional phage library screening is laborious and can map only some of the epitopes. To accelerate and improve epitope identification, we have employed massive sequencing of phage-displayed antigen-specific libraries using the Illumina MiSeq platform. This enabled us to precisely identify the regions of a model antigen, the meningococcal NadA virulence factor, targeted by serum antibodies in vaccinated individuals and to rank hundreds of antigenic fragments according to their immunoreactivity. We found that next generation sequencing can significantly empower the analysis of antigen-specific libraries by allowing simultaneous processing of dozens of library/serum combinations in less than two days, including the time required for antibody-mediated library selection. Moreover, compared with traditional plaque picking, the new technology (named Phage-based Representation OF Immuno-Ligand Epitope Repertoire or PROFILER) provides superior resolution in epitope identification. PROFILER seems ideally suited to streamline and guide rational antigen design, adjuvant selection, and quality control of newly produced vaccines. Furthermore, this method is also susceptible to find important applications in other fields covered by traditional quantitative serology.

  20. Antigen-Specific Antibody Glycosylation Is Regulated via Vaccination

    NARCIS (Netherlands)

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

    2016-01-01

    Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain

  1. Characterization of a human antigen specific helper factor

    International Nuclear Information System (INIS)

    Richardson, B.

    1986-01-01

    While antigen (Ag) specific helper factors have been characterized in mice, similar molecules have not been identified in humans. To characterize human antigen specific helper molecules, an IL-2 dependent tetanus toxoid (T.T.) reactive T cell line was fused with a 6-thioguanine resistant CEM line, and hybrids selected in medium containing hypoxanthine and azaserine. Hybrids were screened by culturing the cells with 35 S-Met then reacting the supernatants with T.T. or hepatitis vaccine immobilized on nitrocellulose. One hybrid, TT6BA-O, was identified which secreted a Met-containing molecule which bound T.T. but not hepatitis vaccine. Supernatants from TT6BA-O, but not the parent CEM line, when added to autologous peripheral blood mononuclear cells (PBMC's) stimulated secretion of T.T. specific antibodies (Abs). Specificity controls demonstrated that TT6BA-O supernatant did not induce antibodies to diphtheria toxoid, hepatitis vaccine or pneumococcal polysaccharide, and total immunoglobulin (lg) synthesis was minimally increased. In contrast, pokeweed mitogen stimulated significant lg synthesis as well as Ab's to pneumococcal polysaccharide and T.T. TT6BA-O supernatant induced anti-T.T.Ab's in autologous PBMC's but not PBMC's from 3 unrelated donors, suggesting that the activity of the helper factor is restricted, possibly by the MHC. The molecular weight of the helper factor was estimated at 100,000-150,000 by Sephacryl S-300 chromatography. Finally, the helper factor could be demonstrated to bind and elute from sephorose-immobilized T.T. and anti-DR antisera, but not anti-lg antisera or the T40/25 monoclonal antibody, which binds a nonpolymorphic determinant on the human T cell receptor. These results demonstrate that human Ag specific helper factors exist, bind antigen and bear class II MHC determinants

  2. Adoptive Immunotherapy for Hematological Malignancies Using T Cells Gene-Modified to Express Tumor Antigen-Specific Receptors

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    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.

  3. Characterizing complex polysera produced by antigen-specific immunization through the use of affinity-selected mimotopes.

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    Galina Denisova

    Full Text Available BACKGROUND: Antigen-based (as opposed to whole organism vaccines are actively being pursued for numerous indications. Even though different formulations may produce similar levels of total antigen-specific antibody, the composition of the antibody response can be quite distinct resulting in different levels of therapeutic activity. METHODOLOGY/PRINCIPAL FINDINGS: Using plasmid-based immunization against the proto-oncogene HER-2 as a model, we have demonstrated that affinity-selected epitope mimetics (mimotopes can provide a defined signature of a polyclonal antibody response. Further, using novel computer algorithms that we have developed, these mimotopes can be used to predict epitope targets. CONCLUSIONS/SIGNIFICANCE: By combining our novel strategy with existing methods of epitope prediction based on physical properties of an individual protein, we believe that this method offers a robust method for characterizing the breadth of epitope-specificity within a specific polyserum. This strategy is useful as a tool for monitoring immunity following vaccination and can also be used to define relevant epitopes for the creation of novel vaccines.

  4. Rapid desensitization induces internalization of antigen-specific IgE on mouse mast cells.

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    Oka, Tatsuya; Rios, Eon J; Tsai, Mindy; Kalesnikoff, Janet; Galli, Stephen J

    2013-10-01

    Rapid desensitization transiently prevents severe allergic reactions, allowing administration of life-saving therapies in previously sensitized patients. However, the mechanisms underlying successful rapid desensitization are not fully understood. We sought to investigate whether the mast cell (MC) is an important target of rapid desensitization in mice sensitized to exhibit IgE-dependent passive systemic anaphylaxis in vivo and to investigate the antigen specificity and underlying mechanisms of rapid desensitization in our mouse model. C57BL/6 mice (in vivo) or primary isolated C57BL/6 mouse peritoneal mast cells (PMCs; in vitro) were passively sensitized with antigen-specific anti-2,4-dinitrophenyl IgE, anti-ovalbumin IgE, or both. MCs were exposed over a short period of time to increasing amounts of antigen (2,4-dinitrophenyl-human serum albumin or ovalbumin) in the presence of extracellular calcium in vitro or by means of intravenous administration to sensitized mice in vivo before challenging the mice with or exposing the PMCs to optimal amounts of specific or irrelevant antigen. Rapidly exposing mice or PMCs to progressively increasing amounts of specific antigen inhibited the development of antigen-induced hypothermia in sensitized mice in vivo and inhibited antigen-induced PMC degranulation and prostaglandin D2 synthesis in vitro. Such MC hyporesponsiveness was induced antigen-specifically and was associated with a significant reduction in antigen-specific IgE levels on MC surfaces. Rapidly exposing MCs to progressively increasing amounts of antigen can both enhance the internalization of antigen-specific IgE on the MC surface and also desensitize these cells in an antigen-specific manner in vivo and in vitro. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen. There is ......Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen...

  6. Functional, Antigen-Specific Stem Cell Memory (TSCM CD4+ T Cells Are Induced by Human Mycobacterium tuberculosis Infection

    Directory of Open Access Journals (Sweden)

    Cheleka A. M. Mpande

    2018-03-01

    Full Text Available BackgroundMaintenance of long-lasting immunity is thought to depend on stem cell memory T cells (TSCM, which have superior self-renewing capacity, longevity and proliferative potential compared with central memory (TCM or effector (TEFF T cells. Our knowledge of TSCM derives primarily from studies of virus-specific CD8+ TSCM. We aimed to determine if infection with Mycobacterium tuberculosis (M. tb, the etiological agent of tuberculosis, generates antigen-specific CD4+ TSCM and to characterize their functional ontology.MethodsWe studied T cell responses to natural M. tb infection in a longitudinal adolescent cohort of recent QuantiFERON-TB Gold (QFT converters and three cross-sectional QFT+ adult cohorts; and to bacillus Calmette–Guerin (BCG vaccination in infants. M. tb and/or BCG-specific CD4 T cells were detected by flow cytometry using major histocompatibility complex class II tetramers bearing Ag85, CFP-10, or ESAT-6 peptides, or by intracellular cytokine staining. Transcriptomic analyses of M. tb-specific tetramer+ CD4+ TSCM (CD45RA+ CCR7+ CD27+ were performed by microfluidic qRT-PCR, and functional and phenotypic characteristics were confirmed by measuring expression of chemokine receptors, cytotoxic molecules and cytokines using flow cytometry.ResultsM. tb-specific TSCM were not detected in QFT-negative persons. After QFT conversion frequencies of TSCM increased to measurable levels and remained detectable thereafter, suggesting that primary M. tb infection induces TSCM cells. Gene expression (GE profiling of tetramer+ TSCM showed that these cells were distinct from bulk CD4+ naïve T cells (TN and shared features of bulk TSCM and M. tb-specific tetramer+ TCM and TEFF cells. These TSCM were predominantly CD95+ and CXCR3+, markers typical of CD8+ TSCM. Tetramer+ TSCM expressed significantly higher protein levels of CCR5, CCR6, CXCR3, granzyme A, granzyme K, and granulysin than bulk TN and TSCM cells. M. tb-specific TSCM were also

  7. Semi-allogeneic dendritic cells can induce antigen-specific T-cell activation, which is not enhanced by concurrent alloreactivity.

    Science.gov (United States)

    Wells, James W; Cowled, Chris J; Darling, David; Guinn, Barbara-Ann; Farzaneh, Farzin; Noble, Alistair; Galea-Lauri, Joanna

    2007-12-01

    Alloreactive T-cell responses are known to result in the production of large amounts of proinflammatory cytokines capable of activating and maturing dendritic cells (DC). However, it is unclear whether these allogeneic responses could also act as an adjuvant for concurrent antigen-specific responses. To examine effects of simultaneous alloreactive and antigen-specific T-cell responses induced by semi-allogeneic DC. Semi-allogeneic DC were generated from the F(1) progeny of inbred strains of mice (C57BL/6 and C3H, or C57BL/6 and DBA). We directly primed antigen-specific CD8(+) and CD4(+) T-cells from OT-I and OT-II mice, respectively, in the absence of allogeneic responses, in vitro, and in the presence or absence of alloreactivity in vivo. In vitro, semi-allogeneic DC cross-presented ovalbumin (OVA) to naïve CD8(+) OT-I transgenic T-cells, primed naïve CD4(+) OT-II transgenic T-cells and could stimulate strong alloreactive T-cell proliferation in a primary mixed lymphocyte reaction (MLR). In vivo, semi-allogeneic DC migrated efficiently to regional lymph nodes but did not survive there as long as autologous DC. In addition, they were not able to induce cytotoxic T-lymphocyte (CTL) activity to a target peptide, and only weakly stimulated adoptively transferred OT-II cells. The CD4(+) response was unchanged in allo-tolerized mice, indicating that alloreactive T-cell responses could not provide help for concurrently activated antigen-specific responses. In an EL4 tumour-treatment model, vaccination with semi-allogeneic DC/EL4 fusion hybrids, but not allogeneic DC/EL4 hybrids, significantly increased mouse survival. Expression of self-Major histocompatibility complex (MHC) by semi-allogeneic DC can cause the induction of antigen-specific immunity, however, concurrently activated allogeneic bystander responses do not provide helper or adjuvant effects.

  8. T-Cell Therapy Using Interleukin-21-Primed Cytotoxic T-Cell Lymphocytes Combined With Cytotoxic T-Cell Lymphocyte Antigen-4 Blockade Results in Long-Term Cell Persistence and Durable Tumor Regression.

    Science.gov (United States)

    Chapuis, Aude G; Roberts, Ilana M; Thompson, John A; Margolin, Kim A; Bhatia, Shailender; Lee, Sylvia M; Sloan, Heather L; Lai, Ivy P; Farrar, Erik A; Wagener, Felecia; Shibuya, Kendall C; Cao, Jianhong; Wolchok, Jedd D; Greenberg, Philip D; Yee, Cassian

    2016-11-01

    Purpose Peripheral blood-derived antigen-specific cytotoxic T cells (CTLs) provide a readily available source of effector cells that can be administered with minimal toxicity in an outpatient setting. In metastatic melanoma, this approach results in measurable albeit modest clinical responses in patients resistant to conventional therapy. We reasoned that concurrent cytotoxic T-cell lymphocyte antigen-4 (CTLA-4) checkpoint blockade might enhance the antitumor activity of adoptively transferred CTLs. Patients and Methods Autologous MART1-specific CTLs were generated by priming with peptide-pulsed dendritic cells in the presence of interleukin-21 and enriched by peptide-major histocompatibility complex multimer-guided cell sorting. This expeditiously yielded polyclonal CTL lines uniformly expressing markers associated with an enhanced survival potential. In this first-in-human strategy, 10 patients with stage IV melanoma received the MART1-specific CTLs followed by a standard course of anti-CTLA-4 (ipilimumab). Results The toxicity profile of the combined treatment was comparable to that of ipilimumab monotherapy. Evaluation of best responses at 12 weeks yielded two continuous complete remissions, one partial response (PR) using RECIST criteria (two PRs using immune-related response criteria), and three instances of stable disease. Infused CTLs persisted with frequencies up to 2.9% of CD8 + T cells for as long as the patients were monitored (up to 40 weeks). In patients who experienced complete remissions, PRs, or stable disease, the persisting CTLs acquired phenotypic and functional characteristics of long-lived memory cells. Moreover, these patients also developed responses to nontargeted tumor antigens (epitope spreading). Conclusion We demonstrate that combining antigen-specific CTLs with CTLA-4 blockade is safe and produces durable clinical responses, likely reflecting both enhanced activity of transferred cells and improved recruitment of new responses

  9. T-Cell Therapy Using Interleukin-21–Primed Cytotoxic T-Cell Lymphocytes Combined With Cytotoxic T-Cell Lymphocyte Antigen-4 Blockade Results in Long-Term Cell Persistence and Durable Tumor Regression

    Science.gov (United States)

    Chapuis, Aude G.; Roberts, Ilana M.; Thompson, John A.; Margolin, Kim A.; Bhatia, Shailender; Lee, Sylvia M.; Sloan, Heather L.; Lai, Ivy P.; Farrar, Erik A.; Wagener, Felecia; Shibuya, Kendall C.; Cao, Jianhong; Wolchok, Jedd D.; Greenberg, Philip D.

    2016-01-01

    Purpose Peripheral blood–derived antigen-specific cytotoxic T cells (CTLs) provide a readily available source of effector cells that can be administered with minimal toxicity in an outpatient setting. In metastatic melanoma, this approach results in measurable albeit modest clinical responses in patients resistant to conventional therapy. We reasoned that concurrent cytotoxic T-cell lymphocyte antigen-4 (CTLA-4) checkpoint blockade might enhance the antitumor activity of adoptively transferred CTLs. Patients and Methods Autologous MART1-specific CTLs were generated by priming with peptide-pulsed dendritic cells in the presence of interleukin-21 and enriched by peptide-major histocompatibility complex multimer-guided cell sorting. This expeditiously yielded polyclonal CTL lines uniformly expressing markers associated with an enhanced survival potential. In this first-in-human strategy, 10 patients with stage IV melanoma received the MART1-specific CTLs followed by a standard course of anti–CTLA-4 (ipilimumab). Results The toxicity profile of the combined treatment was comparable to that of ipilimumab monotherapy. Evaluation of best responses at 12 weeks yielded two continuous complete remissions, one partial response (PR) using RECIST criteria (two PRs using immune-related response criteria), and three instances of stable disease. Infused CTLs persisted with frequencies up to 2.9% of CD8+ T cells for as long as the patients were monitored (up to 40 weeks). In patients who experienced complete remissions, PRs, or stable disease, the persisting CTLs acquired phenotypic and functional characteristics of long-lived memory cells. Moreover, these patients also developed responses to nontargeted tumor antigens (epitope spreading). Conclusion We demonstrate that combining antigen-specific CTLs with CTLA-4 blockade is safe and produces durable clinical responses, likely reflecting both enhanced activity of transferred cells and improved recruitment of new responses

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1985-07-01

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

  11. 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

  12. Analysis of antigen-specific B-cell memory directly ex vivo.

    Science.gov (United States)

    McHeyzer-Williams, Louise J; McHeyzer-Williams, Michael G

    2004-01-01

    Helper T-cell-regulated B-cell memory develops in response to initial antigen priming as a cellular product of the germinal center (GC) reaction. On antigen recall, memory response precursors expand rapidly with exaggerated differentiation into plasma cells to produce the high-titer, high-affinity antibody(Ab) that typifies the memory B-cell response in vivo. We have devised a high-resolution flow cytometric strategy to quantify the emergence and maintenance of antigen-specific memory B cells directly ex vivo. Extended cell surface phenotype establishes a level of cellular diversity not previously appreciated for the memory B-cell compartment. Using an "exclusion transfer" strategy, we ascertain the capacity of two distinct memory B-cell populations to transfer antigen-specific memory into naive adoptive hosts. Finally, we sequence expressed messenger ribonucleic acid (mRNA) from single cells within the population to estimate the level of somatic hypermutation as the best molecular indicator of B-cell memory. In this chapter, we describe the methods used in each of these four sections that serve to provide high-resolution quantification of antigen-specific B-cell memory responses directly ex vivo.

  13. Accelerated production of antigen-specific T-cells for pre-clinical and clinical applications using Gas-permeable Rapid Expansion cultureware (G-Rex)

    Science.gov (United States)

    Vera, Juan F.; Brenner, Lara J.; Gerdemann, Ulrike; Ngo, Minhtran C.; Sili, Uluhan; Liu, Hao; Wilson, John; Dotti, Gianpietro; Heslop, Helen E.; Leen, Ann M.; Rooney, Cliona M.

    2009-01-01

    The clinical manufacture of antigen-specific cytotoxic T lymphocytes (CTL) for adoptive immunotherapy is limited by the complexity and time required to produce large numbers with the desired function and specificity. The culture conditions required are rigorous, and in some cases only achieved in 2cm2 wells in which cell growth is limited by gas exchange, nutrients and waste accumulation. Bioreactors developed to overcome these issues tend to be complex, expensive and not always conducive to CTL growth. We observed that antigen-specific CTL undergo seven to ten divisions post-stimulation. However the expected CTL numbers were achieved only in the first week of culture. By recreating the culture conditions present during this first week - low frequency of antigen-specific T-cells and high frequency of feeder cells - we were able to increase CTL expansion to expected levels which could be sustained for several weeks without affecting phenotype or function. However, the number of 24-well plates needed was excessive and cultures required frequent media changes, increasing complexity and manufacturing costs. Therefore, we evaluated novel gas-permeable culture devices (G-Rex) with a silicone membrane at the base allowing gas exchange to occur uninhibited by depth of medium above. This system effectively supports the expansion of CTL and actually increases output by up to 20-fold while decreasing required technician time. Importantly, this amplified cell expansion is not due to more cell divisions but to reduced cell death. This bioprocess optimization increased T-cell output while decreasing the complexity and cost of CTL manufacture, making cell therapy more accessible. PMID:20445351

  14. Developing antigen-specific therapies in multiple sclerosis: a tale of Tantalus or Ulysses?

    Science.gov (United States)

    van Noort JM

    1999-10-01

    Autoreactive T-cell responses directed to myelin proteins in the central nervous system are widely believed to be crucial in the pathology of multiple sclerosis (MS). However, effective ways of selectively targeting these T-cells in order to alter the clinical course of MS in a predictable manner has yet to be demonstrated. This review discusses two recent developments of crucial importance to the rational development of antigen-specific therapy in MS. The very idea of antigen-specific therapy in MS has long faced the challenge of determinant spreading, i.e., the development of novel autoimmune responses as the consequence of tissue damage. This phenomenon has led many to expect that in ongoing MS, many different pathogenic specificities would accumulate. Obviously, this would render antigen-specific therapy very difficult. Recent data now suggest that determinant spreading is most likely to be a transient phenomenon limited only to the first stages of tissue damage. A second development has changed our perspective on the specificity of individual T-cells and, thus, on the suitability of various ways to implement antigen-specific therapy. Evidence is rapidly accumulating that T-cell receptors are much more cross-reactive than previously assumed. This notion poses unexpected challenges to therapeutic approaches in MS that are based on selective targeting of autoreactive TCR. Vaccination with TCR peptides, administration of anti-TCR antibodies and development of therapeutically altered peptide ligands all depend on a significant level of predictability of pathogenic TCR. With such predictability now turning out to be much lower than was previously hoped, selective TCR-directed strategies for intervention may therefore turn out to be much less effective than anticipated. In the development of antigen-specific therapies, the use of whole protein tolerogens now seems to be the most promising route. Oral, intranasal or iv. administration of antigen remain viable options

  15. Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells.

    Science.gov (United States)

    Correa, Isabel; Ilieva, Kristina M; Crescioli, Silvia; Lombardi, Sara; Figini, Mariangela; Cheung, Anthony; Spicer, James F; Tutt, Andrew N J; Nestle, Frank O; Karagiannis, Panagiotis; Lacy, Katie E; Karagiannis, Sophia N

    2018-01-01

    Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.

  16. Immunization Elicits Antigen-Specific Antibody Sequestration in Dorsal Root Ganglia Sensory Neurons

    Science.gov (United States)

    Gunasekaran, Manojkumar; Chatterjee, Prodyot K.; Shih, Andrew; Imperato, Gavin H.; Addorisio, Meghan; Kumar, Gopal; Lee, Annette; Graf, John F.; Meyer, Dan; Marino, Michael; Puleo, Christopher; Ashe, Jeffrey; Cox, Maureen A.; Mak, Tak W.; Bouton, Chad; Sherry, Barbara; Diamond, Betty; Andersson, Ulf; Coleman, Thomas R.; Metz, Christine N.; Tracey, Kevin J.; Chavan, Sangeeta S.

    2018-01-01

    The immune and nervous systems are two major organ systems responsible for host defense and memory. Both systems achieve memory and learning that can be retained, retrieved, and utilized for decades. Here, we report the surprising discovery that peripheral sensory neurons of the dorsal root ganglia (DRGs) of immunized mice contain antigen-specific antibodies. Using a combination of rigorous molecular genetic analyses, transgenic mice, and adoptive transfer experiments, we demonstrate that DRGs do not synthesize these antigen-specific antibodies, but rather sequester primarily IgG1 subtype antibodies. As revealed by RNA-seq and targeted quantitative PCR (qPCR), dorsal root ganglion (DRG) sensory neurons harvested from either naïve or immunized mice lack enzymes (i.e., RAG1, RAG2, AID, or UNG) required for generating antibody diversity and, therefore, cannot make antibodies. Additionally, transgenic mice that express a reporter fluorescent protein under the control of Igγ1 constant region fail to express Ighg1 transcripts in DRG sensory neurons. Furthermore, neural sequestration of antibodies occurs in mice rendered deficient in neuronal Rag2, but antibody sequestration is not observed in DRG sensory neurons isolated from mice that lack mature B cells [e.g., Rag1 knock out (KO) or μMT mice]. Finally, adoptive transfer of Rag1-deficient bone marrow (BM) into wild-type (WT) mice or WT BM into Rag1 KO mice revealed that antibody sequestration was observed in DRG sensory neurons of chimeric mice with WT BM but not with Rag1-deficient BM. Together, these results indicate that DRG sensory neurons sequester and retain antigen-specific antibodies released by antibody-secreting plasma cells. Coupling this work with previous studies implicating DRG sensory neurons in regulating antigen trafficking during immunization raises the interesting possibility that the nervous system collaborates with the immune system to regulate antigen-mediated responses. PMID:29755449

  17. Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells

    Directory of Open Access Journals (Sweden)

    Isabel Correa

    2018-03-01

    Full Text Available Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1 specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.

  18. Immunization Elicits Antigen-Specific Antibody Sequestration in Dorsal Root Ganglia Sensory Neurons

    Directory of Open Access Journals (Sweden)

    Manojkumar Gunasekaran

    2018-04-01

    Full Text Available The immune and nervous systems are two major organ systems responsible for host defense and memory. Both systems achieve memory and learning that can be retained, retrieved, and utilized for decades. Here, we report the surprising discovery that peripheral sensory neurons of the dorsal root ganglia (DRGs of immunized mice contain antigen-specific antibodies. Using a combination of rigorous molecular genetic analyses, transgenic mice, and adoptive transfer experiments, we demonstrate that DRGs do not synthesize these antigen-specific antibodies, but rather sequester primarily IgG1 subtype antibodies. As revealed by RNA-seq and targeted quantitative PCR (qPCR, dorsal root ganglion (DRG sensory neurons harvested from either naïve or immunized mice lack enzymes (i.e., RAG1, RAG2, AID, or UNG required for generating antibody diversity and, therefore, cannot make antibodies. Additionally, transgenic mice that express a reporter fluorescent protein under the control of Igγ1 constant region fail to express Ighg1 transcripts in DRG sensory neurons. Furthermore, neural sequestration of antibodies occurs in mice rendered deficient in neuronal Rag2, but antibody sequestration is not observed in DRG sensory neurons isolated from mice that lack mature B cells [e.g., Rag1 knock out (KO or μMT mice]. Finally, adoptive transfer of Rag1-deficient bone marrow (BM into wild-type (WT mice or WT BM into Rag1 KO mice revealed that antibody sequestration was observed in DRG sensory neurons of chimeric mice with WT BM but not with Rag1-deficient BM. Together, these results indicate that DRG sensory neurons sequester and retain antigen-specific antibodies released by antibody-secreting plasma cells. Coupling this work with previous studies implicating DRG sensory neurons in regulating antigen trafficking during immunization raises the interesting possibility that the nervous system collaborates with the immune system to regulate antigen-mediated responses.

  19. Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells

    Science.gov (United States)

    Correa, Isabel; Ilieva, Kristina M.; Crescioli, Silvia; Lombardi, Sara; Figini, Mariangela; Cheung, Anthony; Spicer, James F.; Tutt, Andrew N. J.; Nestle, Frank O.; Karagiannis, Panagiotis; Lacy, Katie E.; Karagiannis, Sophia N.

    2018-01-01

    Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires. PMID:29628923

  20. Identification of antigen-specific human monoclonal antibodies using high-throughput sequencing of the antibody repertoire.

    Science.gov (United States)

    Liu, Ju; Li, Ruihua; Liu, Kun; Li, Liangliang; Zai, Xiaodong; Chi, Xiangyang; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-04-22

    High-throughput sequencing of the antibody repertoire provides a large number of antibody variable region sequences that can be used to generate human monoclonal antibodies. However, current screening methods for identifying antigen-specific antibodies are inefficient. In the present study, we developed an antibody clone screening strategy based on clone dynamics and relative frequency, and used it to identify antigen-specific human monoclonal antibodies. Enzyme-linked immunosorbent assay showed that at least 52% of putative positive immunoglobulin heavy chains composed antigen-specific antibodies. Combining information on dynamics and relative frequency improved identification of positive clones and elimination of negative clones. and increase the credibility of putative positive clones. Therefore the screening strategy could simplify the subsequent experimental screening and may facilitate the generation of antigen-specific antibodies. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Research Paper Polyclonal antibodies production against ...

    African Journals Online (AJOL)

    The main aim of this project is to produce polyclonal antibodies directed against the Staphylococcus aureus protein A and their use to appreciate bacteriological analysis of milk quality. In this context, an immunization produce was set up to test and detect in a batch of animals the convenient responder to the injected ...

  2. Polyclonal antibodies of Ganoderma boninense isolated from ...

    African Journals Online (AJOL)

    Polyclonal antibodies of Ganoderma boninense isolated from Malaysian oil palm for detection of basal stem rot disease. ... ELISA-PAb shows better detection as compared to cultural-based method, Ganoderma selective medium (GSM) with an improvement of 18% at nursery trial. The present study also demonstrates ...

  3. Comparative Immunologic Activities of Polyclonal Antibodies ...

    African Journals Online (AJOL)

    Three types of Vibrio cholerae (El tor, Ogawa) whole cell antigens constituted with liquid paraffin adjuvant (LPA), Freund's incomplete adjuvant (FIA) and physiological saline (SA) were used for polyclonal antisera production in adult rabbits. Antisera were compared for serologic reactivities with homologous and ...

  4. A novel polyclonal antibody against human cytomegalovirus ...

    African Journals Online (AJOL)

    Future research should be directed to epitope screening of synthetic HMCV peptides, which could help to understand HCMV infection and virus-neutralising antibodies more fully and to prepare HCMV vaccines and antiviral drugs. Key words: Human cytomegalovirus, AD169 strain, Towne strains, polyclonal antibody.

  5. Total and antigen-specific Ige levels in umbilical cord blood

    Directory of Open Access Journals (Sweden)

    Sybilski AJ

    2009-12-01

    Full Text Available Abstract The present study was conducted to learn whether the perinatal and environmental factors could influence the total and antigen-specific IgE levels in umbilical cord blood. Retrospective data were obtained from 173 mother-infant pairs. Total and specific (for children's food, wheat/grass and house dust mite-HDM cord blood IgE levels were determined using the immunoassay test. The total cord blood IgE was between 0.0-23.08 IU/ml (mean 0.55 ± 2.07 IU/ml; median 0.16 IU/ml. Total IgE levels were significantly higher in boys compared with girls (OR = 2.2; P = 0.007, and in newborns with complicated pregnancy (OR = 2.7; P = 0.003. A greater number of siblings correlated with increases in the total cord blood IgE (P

  6. Improved proliferation of antigen-specific cytolytic T lymphocytes using a multimodal nanovaccine

    Directory of Open Access Journals (Sweden)

    Li B

    2016-11-01

    Full Text Available Bo Li,1,2 Michael Siuta,1 Vanessa Bright,1,2 Dmitry Koktysh,3,4 Brittany K Matlock,5 Megan E Dumas,1 Meiying Zhu,1 Alex Holt,1 Donald Stec,3,6 Shenglou Deng,7 Paul B Savage,7 Sebastian Joyce,8,9 Wellington Pham1,2,6,10–12 1Institute of Imaging Science, Vanderbilt University School of Medicine, 2Department of Radiology and Radiological Sciences, 3Department of Chemistry, Vanderbilt University, 4Vanderbilt Institute of Nanoscale Science and Engineering, 5Vanderbilt Flow Cytometry Shared Resource, Vanderbilt University, 6Vanderbilt Institute of Chemical Biology, 7Department of Chemistry and Biochemistry, Brigham Young University, 8Department of Pathology, Microbiology and Immunology, Vanderbilt University, 9Veterans Administration Tennessee Valley Healthcare System, 10Department of Biomedical Engineering, 11Vanderbilt Ingram Cancer Center, 12Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA Abstract: The present study investigated the immunoenhancing property of our newly designed nanovaccine, that is, its ability to induce antigen-specific immunity. This study also evaluated the synergistic effect of a novel compound PBS-44, an α-galactosylceramide analog, in boosting the immune response induced by our nanovaccine. The nanovaccine was prepared by encapsulating ovalbumin (ova and an adjuvant within the poly(lactic-co-glycolic acid nanoparticles. Quantitative analysis of our study data showed that the encapsulated vaccine was physically and biologically stable; the core content of our nanovaccine was found to be released steadily and slowly, and nearly 90% of the core content was slowly released over the course of 25 days. The in vivo immunization studies exhibited that the nanovaccine induced stronger and longer immune responses compared to its soluble counterpart. Similarly, intranasal inhalation of the nanovaccine induced more robust antigen-specific CD8+ T cell response than intraperitoneal injection of nanovaccine

  7. Polyclonal Antibody Therapies for Clostridium difficile Infection

    Directory of Open Access Journals (Sweden)

    Michael R. Simon

    2014-10-01

    Full Text Available Clostridium difficile infection has emerged as a growing worldwide health problem. The colitis of Clostridium difficile infection results from the synergistic action of C. difficile secreted toxins A and B upon the colon mucosa. A human monoclonal IgG anti-toxin has demonstrated the ability in combination therapy to reduce mortality in C. difficile challenged hamsters. This antibody is currently in a clinical trial for the treatment of human Clostridium difficile infection. More than one group of investigators has considered using polyclonal bovine colostral antibodies to toxins A and B as an oral passive immunization. A significant proportion of the healthy human population possesses polyclonal antibodies to the Clostridium difficile toxins. We have demonstrated that polyclonal IgA derived from the pooled plasma of healthy donors possesses specificity to toxins A and B and can neutralize these toxins in a cell-based assay. This suggests that secretory IgA prepared from such pooled plasma IgA may be able to be used as an oral treatment for Clostridium difficile infection.

  8. Formulation of the bivalent prostate cancer vaccine with surgifoam elicits antigen-specific effector T cells in PSA-transgenic mice.

    Science.gov (United States)

    Karan, Dev

    2017-10-13

    We previously developed and characterized an adenoviral-based prostate cancer vaccine for simultaneous targeting of prostate-specific antigen (PSA) and prostate stem cell antigen (PSCA). We also demonstrated that immunization of mice with the bivalent vaccine (Ad 5 -PSA+PSCA) inhibited the growth of established prostate tumors. However, there are multiple challenges hindering the success of immunological therapies in the clinic. One of the prime concerns has been to overcome the immunological tolerance and maintenance of long-term effector T cells. In this study, we further characterized the use of the bivalent vaccine (Ad 5 -PSA+PSCA) in a transgenic mouse model expressing human PSA in the mouse prostate. We demonstrated the expression of PSA analyzed at the mRNA level (by RT-PCR) and protein level (by immunohistochemistry) in the prostate lobes harvested from the PSA-transgenic (PSA-Tg) mice. We established that the administration of the bivalent vaccine in surgifoam to the PSA-Tg mice induces strong PSA-specific effector CD8 + T cells as measured by IFN-γ secretion and in vitro cytotoxic T-cell assay. Furthermore, the use of surgifoam with Ad 5 -PSA+PSCA vaccine allows multiple boosting vaccinations with a significant increase in antigen-specific CD8 + T cells. These observations suggest that the formulation of the bivalent prostate cancer vaccine (Ad 5 -PSA+PSCA) with surgifoam bypasses the neutralizing antibody response, thus allowing multiple boosting. This formulation is also helpful for inducing an antigen-specific immune response in the presence of self-antigen, and maintains long-term effector CD8 + T cells. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  9. Vaxfectin enhances antigen specific antibody titers and maintains Th1 type immune responses to plasmid DNA immunization.

    Science.gov (United States)

    Reyes, L; Hartikka, J; Bozoukova, V; Sukhu, L; Nishioka, W; Singh, G; Ferrari, M; Enas, J; Wheeler, C J; Manthorpe, M; Wloch, M K

    2001-06-14

    Antigen specific immune responses were characterized after intramuscular immunization of BALB/c mice with 5 antigen encoding plasmid DNAs (pDNAs) complexed with Vaxfectin, a cationic lipid formulation. Vaxfectin increased IgG titers for all of the antigens with no effect on the CTL responses to the 2 antigens for which CTL assays were performed. Both antigen specific IgG1 and IgG2a were increased, although IgG2a remained greater than IgG1. Furthermore, Vaxfectin had no effect on IFN-gamma or IL-4 production by splenocytes re-stimulated with antigen, suggesting that the Th1 type responses typical of intramuscular pDNA immunization were not altered. Studies with IL-6 -/- mice suggest that the antibody enhancement is IL-6 dependent and results in a correlative increase in antigen specific antibody secreting cells.

  10. Single-dilution enzyme-linked immunosorbent assay for quantification of antigen-specific salmonid antibody

    Science.gov (United States)

    Alcorn, S.W.; Pascho, R.J.

    2000-01-01

    An enzyme-linked immunosorbent assay (ELISA) was developed on the basis of testing a single dilution of serum to quantify the level of antibody to the p57 protein of Renibaclerium salmoninarum in sockeye salmon (Oncorhynchus nerka). The levels of antibody were interpolated from a standard curve constructed by relating the optical densities (OD) produced by several dilutions of a high-titer rainbow trout (O. mykiss) antiserum to the p57 protein. The ELISA OD values produced by as many as 36 test sera on each microplate were compared with the standard curve to calculate the antigen-specific antibody activity. Repeated measurements of 36 samples on 3 microplates on each of 6 assay dates indicated that the mean intraassay coefficient of variation (CV) was 6.68% (range, 0-23%) and the mean interassay CV was 8.29% (range, 4-16%). The antibody levels determined for the serum sample from 24 sockeye salmon vaccinated with a recombinant p57 protein generally were correlated with the levels determined by endpoint titration (r2 = 0.936) and with results from another ELISA that was based on extrapolation of antibody levels from a standard curve (r2 = 0.956). The single-dilution antibody ELISA described here increases the number of samples that can be tested on each microplate compared with immunoassays based on analysis of several dilutions of each test serum. It includes controls for interassay standardization and can be used to test fish weighing <3 g.

  11. Characterization of Antigen-Specific B Cells Using Nominal Antigen-Coated Flow-Beads

    Science.gov (United States)

    Akl, Ahmed; Lepetit, Maud; Crochette, Romain; Giral, Magali; Lepourry, Julie; Pallier, Annaick; Castagnet, Stéphanie; Dugast, Emilie; Guillot-Gueguen, Cécile; Jacq-Foucher, Marylène; Saulquin, Xavier; Cesbron, Anne; Laplaud, David; Nicot, Arnaud; Brouard, Sophie; Soulillou, Jean-Paul

    2013-01-01

    In order to characterize the reactivity of B cells against nominal antigens, a method based on the coupling of antigens onto the surface of fluorescent core polystyrene beads was developed. We first demonstrate that murine B cells with a human MOG-specific BCR are able to interact with MOG-coated beads and do not recognize beads coated with human albumin or pp65. B cells purified from human healthy volunteer blood or immunized individuals were tested for their ability to interact with various nominal antigens, including viral, vaccine, self and alloantigens, chosen for their usefulness in studying a variety of pathological processes. A substantial amount of B cells binding self-antigen MOG-coated beads can be detected in normal blood. Furthermore, greater frequencies of B cell against anti-Tetanic Toxin or anti-EBNA1 were observed in primed individuals. This method can reveal increased frequencies of anti-HLA committed B cells in patients with circulating anti-HLA antibodies compared to unsensitized patients and normal individuals. Of interest, those specific CD19 cells were preferentially identified within CD27−IgD+ (i-e naïve) subset. These observations suggest that a broad range of medical situations could benefit from a tool that allows the detection, the quantification and the characterization of antigen-specific blood B cells. PMID:24386360

  12. Antigen-specific tolerance of human alpha1-antitrypsin induced by helper-dependent adenovirus.

    Science.gov (United States)

    Cerullo, V; McCormack, W; Seiler, M; Mane, V; Cela, R; Clarke, C; Rodgers, J R; Lee, B

    2007-12-01

    As efficient and less toxic virus-derived gene therapy vectors are developed, a pressing problem is to avoid immune response to the therapeutic gene product. Secreted therapeutic proteins potentially represent a special problem, as they are readily available to professional antigen-presenting cells throughout the body. Some studies suggest that immunity to serum proteins can be avoided in some mouse strains by using tissue-specific promoters. Here we show that expression of human alpha1-antitrypsin (AAT) was nonimmunogenic in the immune-responsive strain C3H/HeJ, when expressed from helper-dependent (HD) vectors using ubiquitous as well as tissue-specific promoters. Coadministration of less immunogenic HD vectors with an immunogenic first-generation vector failed to immunize, suggesting immune suppression rather than immune stealth. Indeed, mice primed with HD vectors were tolerant to immune challenge with hAAT emulsified in complete Freund's adjuvant. Such animals developed high-titer antibodies to coemulsified human serum albumin, showing that tolerance was antigen specific. AAT-specific T cell responses were depressed in tolerized animals, suggesting that tolerance affects both T and B cells. These results are consistent with models of high-dose tolerance of B cells and certain other suppressive mechanisms, and suggest that a high level of expression from HD vectors can be sufficient to induce specific immune tolerance to serum proteins.

  13. Augmentation of antigen-specific immune responses using DNA-fusogenic liposome vaccine

    International Nuclear Information System (INIS)

    Yoshikawa, Tomoaki; Imazu, Susumu; Gao Jianqing; Hayashi, Kazuyuki; Tsuda, Yasuhiro; Shimokawa, Mariko; Sugita, Toshiki; Niwa, Takako; Oda, Atushi; Akashi, Mitsuru; Tsutsumi, Yasuo; Mayumi, Tadanori; Nakagawa, Shinsaku

    2004-01-01

    In an attempt to enhance the immunological efficacy of genetic immunization, we investigated a new biological means for delivering antigen gene directly to the cytoplasm via membrane fusion. In this context, we investigated fusogenic liposome (FL) encapsulating DNA as a possible genetic immunization vehicle. RT-PCR analysis indicated that a FL could introduce and express encapsulating OVA gene efficiently and rapidly in vitro. Consistent with this observation, an in vitro assay showed that FL-mediated antigen-gene delivery can induce potent presentation of antigen via the MHC class I-dependent pathway. Accordingly, immunization with FL containing the OVA-gene induced potent OVA-specific Th1 and Th2 cytokine production. Additionally, OVA-specific CTL responses and antibody production were also observed in systemic compartments including the spleen, upon immunization with the OVA-gene encapsulating FL. These findings suggest that FL is an effective genetic immunization carrier system for the stimulation of antigen-specific immune responses against its encoding antigen

  14. T Lymphocyte-Endothelial Interactions: Emerging Understanding of Trafficking and Antigen-Specific Immunity

    Directory of Open Access Journals (Sweden)

    Christopher Vincent Carman

    2015-11-01

    Full Text Available Antigen-specific immunity requires regulated trafficking of T cells in and out of diverse tissues in order to orchestrate lymphocyte development, immune surveillance, responses and memory. The endothelium serves as a unique barrier, as well as a sentinel, between the blood and the tissues and as such it plays an essential locally tuned role in regulating T cell migration and information exchange. While it is well established that chemoattractants and adhesion molecules are major determinants of T cell trafficking, emerging studies have now enumerated a large number of molecular players as well as a range of discrete cellular remodeling activities (e.g. transmigratory cups and invadosome-like protrusions, IPLs that participate in directed migration and pathfinding by T cells. In addition to providing trafficking cues, intimate cell-cell interaction between lymphocytes and endothelial cells provide instruction to T cells that influence their activation and differentiation states. Perhaps the most intriguing and underappreciated of these ‘sentinel’ roles is the ability of the endothelium to act as a non-hematopoietic ‘semi-professional’ antigen-presenting cell. Close contacts between circulating T cells and antigen-presenting endothelium may play unique non-redundant roles in shaping adaptive immune responses within the periphery. A better understanding of the mechanisms directing T cell trafficking and the antigen-presenting role of the endothelium may not only increase our knowledge of the adaptive immune response but also empower the utility of emerging immunomodulatory therapeutics.

  15. Development of an epitope panel for consistent identification of antigen-specific T-cells in humans

    DEFF Research Database (Denmark)

    Fløe, Andreas; Løppke, Caroline; Hilberg, Ole

    2017-01-01

    Objective We aimed to establish a panel of MHC-peptide multimers suitable as a positive control in detection of HLA A*0201 restricted antigen specific T-cells (ASTC) by flow cytometry. Materials and methods MHC Dextramers were loaded with HLA A*0201 binding peptides from viral antigens and melano...

  16. Polyclonal and monoclonal antibodies in clinic.

    Science.gov (United States)

    Wootla, Bharath; Denic, Aleksandar; Rodriguez, Moses

    2014-01-01

    Immunoglobulins (Ig) or antibodies are heavy plasma proteins, with sugar chains added to amino-acid residues by N-linked glycosylation and occasionally by O-linked glycosylation. The versatility of antibodies is demonstrated by the various functions that they mediate such as neutralization, agglutination, fixation with activation of complement and activation of effector cells. Naturally occurring antibodies protect the organism against harmful pathogens, viruses and infections. In addition, almost any organic chemical induces antibody production of antibodies that would bind specifically to the chemical. These antibodies are often produced from multiple B cell clones and referred to as polyclonal antibodies. In recent years, scientists have exploited the highly evolved machinery of the immune system to produce structurally and functionally complex molecules such as antibodies from a single B clone, heralding the era of monoclonal antibodies. Most of the antibodies currently in the clinic, target components of the immune system, are not curative and seek to alleviate symptoms rather than cure disease. Our group used a novel strategy to identify reparative human monoclonal antibodies distinct from conventional antibodies. In this chapter, we discuss the therapeutic relevance of both polyclonal and monoclonal antibodies in clinic.

  17. Manipulating the Lewis antigen specificity of the cholesterol-dependent cytolysin lectinolysin

    Directory of Open Access Journals (Sweden)

    Sara eLawrence

    2012-11-01

    Full Text Available The cholesterol-dependent cytolysins (CDCs attack cells by punching large holes in their membranes. Lectinolysin from Streptococcus mitis is unique among CDCs due to the presence of an N-terminal lectin domain that enhances the pore-forming activity of the toxin. We recently determined the crystal structures of the lectin domain in complex with various glycans. These structures revealed the molecular basis for the Lewis antigen specificity of the toxin. Based on this information we have used in silico molecular modelling to design a mutant toxin, which we predicted would increase its specificity for Lewis y, an antigen found on the surface of cancer cells. Surprisingly, we found by surface plasmon resonance binding experiments that the resultant mutant lectin domain exhibited higher specificity for Lewis b antigens instead. We then undertook comparative crystallographic and molecular dynamics simulation studies of the wild-type and mutant lectin domains to understand the molecular basis for the disparity between the theoretical and experimental results. The crystallographic results revealed that the net number of interactions between Lewis y and wild-type versus mutant was unchanged whereas there was a loss of a hydrogen bond between mutant and Lewis b compared to wild-type. In contrast, the molecular dynamics studies revealed that the Lewis b antigen spent more time in the binding pocket of the mutant compared to wild-type and the reverse was true for Lewis y. The results of these simulation studies are consistent with the conclusions drawn from the surface plasmon resonance studies. This work is part of a program to engineer lectinolysin so that it will target and kill specific cells in human diseases.

  18. MRI contrast demonstration of antigen-specific targeting with an iron-based ferritin construct

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Edward G., E-mail: edward_walsh@brown.edu [Brown University, Department of Neuroscience (United States); Mills, David R. [Rhode Island Hospital/Warren Alpert Medical School of Brown University, Division of Hematology and Oncology, Department of Medicine (United States); Lim, Sierin; Sana, Barindra [Nanyang Technological University, Division of Bioengineering (Singapore); Brilliant, Kate E. [Rhode Island Hospital/Warren Alpert Medical School of Brown University, Division of Hematology and Oncology, Department of Medicine (United States); Park, William K. C. [Rhode Island Hospital, Department of Diagnostic Imaging (United States)

    2013-01-15

    A genetically modified ferritin has been examined for its properties as a tumor-selective magnetic resonance imaging (MRI) contrast agent. The engineered ferritin described herein was derived from Archaeoglobus fulgidus (AfFtn-AA), which stores a significantly greater quantity of iron than wild-type ferritins. Relaxivity measurements were taken at 3 Tesla of ferritin particles uniformly distributed in an agarose gel to assess relaxivities r{sub 1} and r{sub 2}. The r{sub 1} and r{sub 2} values of the uniformly distributed modified ferritin were significantly higher (r{sub 1} = 1,290 mM{sup -1} s{sup -1} and r{sub 2} = 5,740 mM{sup -1} s{sup -1}) than values observed for wild-type ferritin (e.g., horse spleen, r{sub 1} = 0.674 mM{sup -1} s{sup -1}, r{sub 2} = 95.54 mM{sup -1} s{sup -1}). The modified iron-enriched ferritin (14.5 nm diameter) was conjugated with a monoclonal antibody (10 nm length) against rat Necl-5, a cell surface glycoprotein overexpressed by many epithelial cancers. In vitro studies showed strong reactivity of the assembled nanoconjugate to transformed Necl-5 positive rat prostate epithelial cells. Furthermore, MRI demonstrated a significant T{sub 2} contrast with negligible T{sub 1} effect when bound to cells. These findings highlight the utility of the modified ferritin construct as a novel MRI contrast agent that can be manipulated to target antigen-specific tissues.

  19. Apoptotic Effect of Anti myeloma Polyclonal Antibodies on The Growth of Myeloma Cells

    International Nuclear Information System (INIS)

    Abd El-Ghany, I.Y.; El-Kolaly, M.T.; Moustafa, K.A.; El-Shershaby, H.M.; Sayed, A.A.; Borai, I.H.; El-Lahloby, N.M.

    2013-01-01

    Multiple myeloma (MM) is a malignancy characterized by proliferation of plasma cells. Cancer immunotherapy is a major branch of biological therapy that utilizes living cells and their products. The aim of this study is to produce and evaluate the antiproliferative effect of anti myeloma polyclonal antibodies (with and without labelling with radioactive isotopes) against the growth of myeloma cells. The production of polyclonal antibodies (PAb) was generated by immunizing five healthy female mature white New-Zealand rabbits with myeloma cells (SP2/OR) through primary injection and five booster doses. The preparation of labelled anti myeloma antibodies was carried out using chloramine-T method and it was purified using PD-10 chromatographic column. The results obtained revealed that anti myeloma polyclonal antibodies inhibited proliferation and induced apoptosis of myeloma cell lines in vitro and induced apoptosis after serial intraperitoneal injection of PAb in ascites bearing mice in vivo. The present study suggested that the effect of labelled anti myeloma antibodies on myeloma cells growth inhibition was more effective than that of anti myeloma antibodies without labelling which is due to the cytotoxic effect of ionizing radiation. Apoptosis triggered by PAb was confirmed by flow cytometry, caspase -8 and -9 and β2-microglobulin.

  20. Antigenic specificity and morphologic characteristics of Chlamydia trachomatis, strain SFPD, isolated from hamsters with proliferative ileitis.

    Science.gov (United States)

    Fox, J G; Stills, H F; Paster, B J; Dewhirst, F E; Yan, L; Palley, L; Prostak, K

    1993-10-01

    Profound diarrhea associated with proliferating intestinal cells containing intraepithelial campylobacter-like organisms (ICLO) occurs in a variety of mammalian hosts, particularly swine and hamsters. Recently, intracellular bacteria were isolated from proliferative intestinal tissue of hamsters and propagated in intestine cell line 407. Oral inoculation of hamsters with cell culture lysates containing these organisms reproduced the disease in susceptible hamsters. In the present study, an intracellular bacterium from the INT 407 cell line was shown by a variety of techniques to be a member of the genus Chlamydia and has been designated Chlamydia sp. strain SFPD. McCoy cells infected with Chlamydia sp. strain SFPD demonstrated bright fluorescent-stained intracytoplasmic inclusions when examined with fluorescein-labeled species-specific C. trachomatis monoclonal antibodies. The organism also reacted to fluorescein-labeled polyclonal but not monoclonal ICLO "omega" antisera. Ultrastructural examination of the Chlamydia sp. strain SFPD from McCoy cells revealed electrondense elementary bodies and a less electron-dense reticulate-like body that was circular; both features are consistent in morphology to developmental forms of Chlamydia and do not conform to ICLO morphology. Molecular studies, 16S ribosomal sequence analysis, and sequencing of the outer membrane protein confirmed that the isolate is a C. trachomatis closely related to the mouse pneumonitis strain of C. trachomatis.

  1. Affinity isolation of antigen-specific circulating B cells for generation of phage display-derived human monoclonal antibodies

    DEFF Research Database (Denmark)

    Ditzel, Henrik

    2009-01-01

    A method is described for affinity isolation of antigen-specific circulating B cells of interest for subsequent generation of immune antibody phage display libraries. This approach should overcome the problem of low yields of monoclonal antibodies of interest in the libraries generated from...... peripheral blood lymphocytes caused by the low abundance of antigen-specific B cells in the circulation. The preselection of B cells is based on the specificity of the surface Ig receptor and is accomplished using the antigen of interest conjugated to magnetic beads. This method should significantly increase...... the frequency of antibody phage particles of interest in the library and allow for efficient isolation monoclonal antibodies with the predefined specificity....

  2. Immunizations with hepatitis B viral antigens and a TLR7/8 agonist adjuvant induce antigen-specific immune responses in HBV-transgenic mice

    Directory of Open Access Journals (Sweden)

    Ying Wang

    2014-12-01

    Conclusions: Immunization with CL097-conjugated HBV-Ag reversed immune tolerance in HBV-Tg mice and induced antigen-specific immune responses. TLR7/8 agonists appear to be potent adjuvants for the induction of antigen-specific Th1 responses in an immune tolerant state.

  3. Induction of antigen-specific immunity by pH-sensitive carbonate apatite as a potent vaccine carrier

    International Nuclear Information System (INIS)

    Hebishima, Takehisa; Tada, Seiichi; Takeshima, Shin-nosuke; Akaike, Toshihiro; Ito, Yoshihiro; Aida, Yoko

    2011-01-01

    Highlights: ► To develop effective vaccine, we examined the effects of CO 3 Ap as an antigen carrier. ► OVA contained in CO 3 Ap was taken up by BMDCs more effectively than free OVA. ► OVA-immunized splenocytes was activated by OVA contained in CO 3 Ap effectively. ► OVA contained in CO 3 Ap induced strong OVA-specific immune responses to C57BL/6 mice. ► CO 3 Ap is promising antigen carrier for the achievement of effective vaccine. -- Abstract: The ability of carbonate apatite (CO 3 Ap) to enhance antigen-specific immunity was examined in vitro and in vivo to investigate its utility as a vaccine carrier. Murine bone marrow-derived dendritic cells took up ovalbumin (OVA) containing CO 3 Ap more effectively than free OVA. Interestingly, mice immunized with OVA-containing CO 3 Ap produced OVA-specific antibodies more effectively than mice immunized with free OVA. Furthermore, immunization of C57BL/6 mice with OVA-containing CO 3 Ap induced the proliferation and antigen-specific production of IFN-γ by splenocytes more strongly than immunization with free OVA. Moreover, no significant differences were detected in the induction of delayed-type hypersensitivity responses, an immune reaction involving an antigen-specific, cell-mediated immune response between OVA-containing CO 3 Ap and OVA-containing alumina salt (Alum), suggesting that CO 3 Ap induced cell-mediated immune response to the same degree as Alum, which is commonly used for clinical applications. This study is the first to demonstrate the induction of antigen-specific immune responses in vivo by CO 3 Ap.

  4. Generation of Tumor Antigen-Specific iPSC-Derived Thymic Emigrants Using a 3D Thymic Culture System

    Directory of Open Access Journals (Sweden)

    Raul Vizcardo

    2018-03-01

    Full Text Available Summary: Induced pluripotent stem cell (iPSC-derived T cells may provide future therapies for cancer patients, but those generated by current methods, such as the OP9/DLL1 system, have shown abnormalities that pose major barriers for clinical translation. Our data indicate that these iPSC-derived CD8 single-positive T cells are more like CD4+CD8+ double-positive T cells than mature naive T cells because they display phenotypic markers of developmental arrest and an innate-like phenotype after stimulation. We developed a 3D thymic culture system to avoid these aberrant developmental fates, generating a homogeneous subset of CD8αβ+ antigen-specific T cells, designated iPSC-derived thymic emigrants (iTEs. iTEs exhibit phenotypic and functional similarities to naive T cells both in vitro and in vivo, including the capacity for expansion, memory formation, and tumor suppression. These data illustrate the limitations of current methods and provide a tool to develop the next generation of iPSC-based antigen-specific immunotherapies. : A barrier for clinical application of iPSC-derived CD8 T cells using OP9/DLL1 is their abnormal biology. Vizcardo et al. show that a 3D thymic culture system enables the generation of a homogeneous antigen-specific T cell subset, named iTEs, which closely mimics naive T cells and exhibits potent anti-tumor activity. Keywords: thymopoiesis, T cell differentiation, iPSC differentiation, adoptive cell transfer, naïve T cell, recent rhymic emigrants, fetal thymus organ culture, immunotherapy, 3D culture, tumor antigen specific T cell

  5. Isolation and characterization of antigen-specific alpaca (Lama pacos) VHH antibodies by biopanning followed by high-throughput sequencing.

    Science.gov (United States)

    Miyazaki, Nobuo; Kiyose, Norihiko; Akazawa, Yoko; Takashima, Mizuki; Hagihara, Yosihisa; Inoue, Naokazu; Matsuda, Tomonari; Ogawa, Ryu; Inoue, Seiya; Ito, Yuji

    2015-09-01

    The antigen-binding domain of camelid dimeric heavy chain antibodies, known as VHH or Nanobody, has much potential in pharmaceutical and industrial applications. To establish the isolation process of antigen-specific VHH, a VHH phage library was constructed with a diversity of 8.4 × 10(7) from cDNA of peripheral blood mononuclear cells of an alpaca (Lama pacos) immunized with a fragment of IZUMO1 (IZUMO1PFF) as a model antigen. By conventional biopanning, 13 antigen-specific VHHs were isolated. The amino acid sequences of these VHHs, designated as N-group VHHs, were very similar to each other (>93% identity). To find more diverse antibodies, we performed high-throughput sequencing (HTS) of VHH genes. By comparing the frequencies of each sequence between before and after biopanning, we found the sequences whose frequencies were increased by biopanning. The top 100 sequences of them were supplied for phylogenic tree analysis. In total 75% of them belonged to N-group VHHs, but the other were phylogenically apart from N-group VHHs (Non N-group). Two of three VHHs selected from non N-group VHHs showed sufficient antigen binding ability. These results suggested that biopanning followed by HTS provided a useful method for finding minor and diverse antigen-specific clones that could not be identified by conventional biopanning. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Daniel S Chen

    2005-10-01

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

  7. Administration of sulfosuccinimidyl-4-[N-maleimidomethyl] cyclohexane-1-carboxylate conjugated GP10025–33 peptide-coupled spleen cells effectively mounts antigen-specific immune response against mouse melanoma

    International Nuclear Information System (INIS)

    Chang, Xiaoli; Xia, Chang-Qing

    2015-01-01

    It remains a top research priority to develop immunotherapeutic approaches to induce potent antigen-specific immune responses against tumors. However, in spite of some promising results, most strategies are ineffective because they generate low numbers of tumor-reactive cytotoxic T lymphocytes (CTLs). Here we designed a strategy to enhance antigen-specific immune response via administering sulfosuccinimidyl-4-[N-maleimidomethyl] cyclohexane-1-carboxylate (sulfo-SMCC)-conjugated melanoma tumor antigen GP100 25–33 peptide-coupled syngeneic spleen cells in a mouse model of melanoma. We found that infusion of GP100 25–33 peptide-coupled spleen cells significantly attenuated the growth of melanoma in prophylactic and therapeutic immunizations. Consistent with these findings, the adoptive transfer of spleen cells from immunized mice to naïve syngeneic mice was able to transfer anti-tumor effect, suggesting that GP100 25–33 peptide-specific immune response was induced. Further studies showed that, CD8+ T cell proliferation and the frequency of interferon (IFN)-γ-producing CD8+ T cells upon ex vivo stimulation by GP100 25–33 were significantly increased compared to control groups. Tumor antigen, GP100 25–23 specific immune response was also confirmed by ELISpot and GP100-tetramer assays. This approach is simple, easy-handled, and efficiently delivering antigens to lymphoid tissues. Our study offers an opportunity for clinically translating this approach into tumor immunotherapy. - Highlights: • Infusion of GP100 25–33 -coupled spleen cells leads to potent anti-melanoma immunity. • GP100 25–33 -coupled spleen cell treatment induces antigen-specific IFN-γ-producing CD8 T cells. • This approach takes advantage of homing nature of immune cells.

  8. Administration of sulfosuccinimidyl-4-[N-maleimidomethyl] cyclohexane-1-carboxylate conjugated GP100{sub 25–33} peptide-coupled spleen cells effectively mounts antigen-specific immune response against mouse melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Xiaoli [Department of Hematology, Xuanwu Hospital, Capital Medical University, Beijing (China); Xia, Chang-Qing, E-mail: cqx65@yahoo.com [Department of Hematology, Xuanwu Hospital, Capital Medical University, Beijing (China); Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL32610 (United States)

    2015-12-04

    It remains a top research priority to develop immunotherapeutic approaches to induce potent antigen-specific immune responses against tumors. However, in spite of some promising results, most strategies are ineffective because they generate low numbers of tumor-reactive cytotoxic T lymphocytes (CTLs). Here we designed a strategy to enhance antigen-specific immune response via administering sulfosuccinimidyl-4-[N-maleimidomethyl] cyclohexane-1-carboxylate (sulfo-SMCC)-conjugated melanoma tumor antigen GP100{sub 25–33} peptide-coupled syngeneic spleen cells in a mouse model of melanoma. We found that infusion of GP100{sub 25–33} peptide-coupled spleen cells significantly attenuated the growth of melanoma in prophylactic and therapeutic immunizations. Consistent with these findings, the adoptive transfer of spleen cells from immunized mice to naïve syngeneic mice was able to transfer anti-tumor effect, suggesting that GP100{sub 25–33} peptide-specific immune response was induced. Further studies showed that, CD8+ T cell proliferation and the frequency of interferon (IFN)-γ-producing CD8+ T cells upon ex vivo stimulation by GP100{sub 25–33} were significantly increased compared to control groups. Tumor antigen, GP100{sub 25–23} specific immune response was also confirmed by ELISpot and GP100-tetramer assays. This approach is simple, easy-handled, and efficiently delivering antigens to lymphoid tissues. Our study offers an opportunity for clinically translating this approach into tumor immunotherapy. - Highlights: • Infusion of GP100{sub 25–33}-coupled spleen cells leads to potent anti-melanoma immunity. • GP100{sub 25–33}-coupled spleen cell treatment induces antigen-specific IFN-γ-producing CD8 T cells. • This approach takes advantage of homing nature of immune cells.

  9. Physiological level production of antigen-specific human immunoglobulin in cloned transchromosomic cattle.

    Directory of Open Access Journals (Sweden)

    Akiko Sano

    Full Text Available Therapeutic human polyclonal antibodies (hpAbs derived from pooled plasma from human donors are Food and Drug Administration approved biologics used in the treatment of a variety of human diseases. Powered by the natural diversity of immune response, hpAbs are effective in treating diseases caused by complex or quickly-evolving antigens such as viruses. We previously showed that transchromosomic (Tc cattle carrying a human artificial chromosome (HAC comprising the entire unrearranged human immunoglobulin heavy-chain (hIGH and kappa-chain (hIGK germline loci (named as κHAC are capable of producing functional hpAbs when both of the bovine immunoglobulin mu heavy-chains, bIGHM and bIGHML1, are homozygously inactivated (double knockouts or DKO. However, B lymphocyte development in these Tc cattle is compromised, and the overall production of hpAbs is low. Here, we report the construction of an improved HAC, designated as cKSL-HACΔ, by incorporating all of the human immunoglobulin germline loci into the HAC. Furthermore, for avoiding the possible human-bovine interspecies incompatibility between the human immunoglobulin mu chain protein (hIgM and bovine transmembrane α and β immunoglobulins (bIgα and bIgβ in the pre-B cell receptor (pre-BCR complex, we partially replaced (bovinized the hIgM constant domain with the counterpart of bovine IgM (bIgM that is involved in the interaction between bIgM and bIgα/Igβ; human IgM bovinization would also improve the functionality of hIgM in supporting B cell activation and proliferation. We also report the successful production of DKO Tc cattle carrying the cKSL-HACΔ (cKSL-HACΔ/DKO, the dramatic improvement of B cell development in these cattle and the high level production of hpAbs (as measured for the human IgG isotype in the plasma. We further demonstrate that, upon immunization by tumor immunogens, high titer tumor immunogen-specific human IgG (hIgG can be produced from such Tc cattle.

  10. 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.

  11. Recombinant Polyclonal Antibody Libraries for Breast Cancer Therapy

    National Research Council Canada - National Science Library

    Sharon, Jacqueline

    1999-01-01

    .... In the present study, V region genes for construction of a polyclonal Fab phage display library were obtained from the spleen, bone marrow, and intestine of a BALB/c mouse that had been immunized with BT-20 cells...

  12. Pretreatment antigen-specific immunity and regulation - association with subsequent immune response to anti-tumor DNA vaccination.

    Science.gov (United States)

    Johnson, Laura E; Olson, Brian M; McNeel, Douglas G

    2017-07-18

    Immunotherapies have demonstrated clinical benefit for many types of cancers, however many patients do not respond, and treatment-related adverse effects can be severe. Hence many efforts are underway to identify treatment predictive biomarkers. We have reported the results of two phase I trials using a DNA vaccine encoding prostatic acid phosphatase (PAP) in patients with biochemically recurrent prostate cancer. In both trials, persistent PAP-specific Th1 immunity developed in some patients, and this was associated with favorable changes in serum PSA kinetics. In the current study, we sought to determine if measures of antigen-specific or antigen non-specific immunity were present prior to treatment, and associated with subsequent immune response, to identify possible predictive immune biomarkers. Patients who developed persistent PAP-specific, IFNγ-secreting immune responses were defined as immune "responders." The frequency of peripheral T cell and B cell lymphocytes, natural killer cells, monocytes, dendritic cells, myeloid derived suppressor cells, and regulatory T cells were assessed by flow cytometry and clinical laboratory values. PAP-specific immune responses were evaluated by cytokine secretion in vitro, and by antigen-specific suppression of delayed-type hypersensitivity to a recall antigen in an in vivo SCID mouse model. The frequency of peripheral blood cell types did not differ between the immune responder and non-responder groups. Non-responder patients tended to have higher PAP-specific IL-10 production pre-vaccination (p = 0.09). Responder patients had greater preexisting PAP-specific bystander regulatory responses that suppressed DTH to a recall antigen (p = 0.016). While our study population was small (n = 38), these results suggest that different measures of antigen-specific tolerance or regulation might help predict immunological outcome from DNA vaccination. These will be prospectively evaluated in an ongoing randomized, phase II trial.

  13. A novel and effective cancer immunotherapy mouse model using antigen-specific B cells selected in vitro.

    Directory of Open Access Journals (Sweden)

    Tatsuya Moutai

    Full Text Available Immunotherapies such as adoptive transfer of T cells or natural killer cells, or monoclonal antibody (MoAb treatment have recently been recognized as effective means to treat cancer patients. However, adoptive transfer of B cells or plasma cells producing tumor-specific antibodies has not been applied as a therapy because long-term culture and selective expansion of antigen-specific B cells has been technically very difficult. Here, we describe a novel cancer immunotherapy that uses B-cell adoptive transfer. We demonstrate that germinal-center-like B cells (iGB cells induced in vitro from mouse naïve B cells become plasma cells and produce IgG antibodies for more than a month in the bone marrow of non-irradiated recipient mice. When transferred into mice, iGB cells producing antibody against a surrogate tumor antigen suppressed lung metastasis and growth of mouse melanoma cells expressing the same antigen and prolonged survival of the recipients. In addition, we have developed a novel culture system called FAIS to selectively expand antigen-specific iGB cells utilizing the fact that iGB cells are sensitive to Fas-induced cell death unless their antigen receptors are ligated by membrane-bound antigens. The selected iGB cells efficiently suppressed lung metastasis of melanoma cells in the adoptive immunotherapy model. As human blood B cells can be propagated as iGB cells using culture conditions similar to the mouse iGB cell cultures, our data suggest that it will be possible to treat cancer-bearing patients by the adoptive transfer of cancer-antigen-specific iGB cells selected in vitro. This new adoptive immunotherapy should be an alternative to the laborious development of MoAb drugs against cancers for which no effective treatments currently exist.

  14. Hierarchical Bayesian mixture modelling for antigen-specific T-cell subtyping in combinatorially encoded flow cytometry studies

    DEFF Research Database (Denmark)

    Lin, Lin; Chan, Cliburn; Hadrup, Sine R

    2013-01-01

    subtype identification in this novel, general model framework, and provide a detailed example using simulated data. We then describe application to a data set from an experimental study of antigen-specific T-cell subtyping using combinatorially encoded assays in human blood samples. Summary comments...... profiling in many biological areas, traditional flow cytometry measures relative levels of abundance of marker proteins using fluorescently labeled tags that identify specific markers by a single-color. One specific and important recent development in this area is the use of combinatorial marker assays...

  15. Use of a solid-phase radioimmunoassay and formalin-fixed whole bacterial antigen in the detection of antigen-specific immunoglobulin in prostatic fluid.

    OpenAIRE

    Shortliffe, L M; Wehner, N; Stamey, T A

    1981-01-01

    The prostatic fluid of two patients with Escherichia coli bacterial prostatitis was analyzed for evidence of a local immune response to bacterial infection. A solid-phase radioimmunoassay was modified to measure the immunoglobulin (Ig)A and IgG antigen-specific antibody responses to infecting bacteria in serum and prostatic fluid from patient. Formalin-fixed whole E. coli were used as antigen. In one patient with acute E. coli prostatic infection, measurements of antigen-specific antibody con...

  16. Mycobacterium avium and purified protein derivative-specific cytotoxicity mediated by CD4+ lymphocytes from healthy HIV-seropositive and-seronegative individuals

    DEFF Research Database (Denmark)

    Ravn, P; Pedersen, B K

    1996-01-01

    by a defect in the cytotoxic capacity of the individual CD4+ lymphocyte after antigen stimulation, and it could not be explained by a reduction in the total number of CD4+ cells before antigen stimulation. The antigen-specific cytotoxic activity was, however, closely related to the ability of the CD4+ T cells...

  17. Polyclonal antibodies for the detection of Trypanosoma cruzi circulating antigens.

    Directory of Open Access Journals (Sweden)

    Edith S Málaga-Machaca

    2017-11-01

    Full Text Available Detection of Trypanosoma cruzi antigens in clinical samples is considered an important diagnostic tool for Chagas disease. The production and use of polyclonal antibodies may contribute to an increase in the sensitivity of immunodiagnosis of Chagas disease.Polyclonal antibodies were raised in alpacas, rabbits, and hens immunized with trypomastigote excreted-secreted antigen, membrane proteins, trypomastigote lysate antigen and recombinant 1F8 to produce polyclonal antibodies. Western blot analysis was performed to determine specificity of the developed antibodies. An antigen capture ELISA of circulating antigens in serum, plasma and urine samples was developed using IgY polyclonal antibodies against T. cruzi membrane antigens (capture antibody and IgG from alpaca raised against TESA. A total of 33 serum, 23 plasma and 9 urine samples were analyzed using the developed test. Among serum samples, compared to serology, the antigen capture ELISA tested positive in 55% of samples. All plasma samples from serology positive subjects were positive in the antigen capture ELISA. All urine positive samples had corresponding plasma samples that were also positive when tested by the antigen capture ELISA.Polyclonal antibodies are useful for detection of circulating antigens in both the plasma and urine of infected individuals. Detection of antigens is direct evidence of the presence of the parasite, and could be a better surrogate of current infection status.

  18. Variable Domain N-Linked Glycans Acquired During Antigen-Specific Immune Responses Can Contribute to Immunoglobulin G Antibody Stability

    Directory of Open Access Journals (Sweden)

    Fleur S. van de Bovenkamp

    2018-04-01

    Full Text Available Immunoglobulin G (IgG can contain N-linked glycans in the variable domains, the so-called Fab glycans, in addition to the Fc glycans in the CH2 domains. These Fab glycans are acquired following introduction of N-glycosylation sites during somatic hypermutation and contribute to antibody diversification. We investigated whether Fab glycans may—in addition to affecting antigen binding—contribute to antibody stability. By analyzing thermal unfolding profiles of antibodies with or without Fab glycans, we demonstrate that introduction of Fab glycans can improve antibody stability. Strikingly, removal of Fab glycans naturally acquired during antigen-specific immune responses can deteriorate antibody stability, suggesting in vivo selection of stable, glycosylated antibodies. Collectively, our data show that variable domain N-linked glycans acquired during somatic hypermutation can contribute to IgG antibody stability. These findings indicate that introducing Fab glycans may represent a mechanism to improve therapeutic/diagnostic antibody stability.

  19. Tracking by flow cytometry antigen-specific follicular helper T cells in wild-type animals after protein vaccination.

    Science.gov (United States)

    Chakarov, Svetoslav; Fazilleau, Nicolas

    2015-01-01

    Flow cytometry is a valuable technology used in immunology to characterize and enumerate the different cell subpopulations specific for a nonself-antigen in the context of an ongoing immune response. Among them, follicular helper T cells are the cognate regulators of B cells in secondary lymphoid tissues. Thus, tracking them is of high interest especially in the context of protein vaccination. For this purpose, transgenic antigen-receptor mouse models have been largely used. It is now clear that transgenic models are not always the best means to study the dynamics of the immune response since they can modify the response. In this chapter, we describe how to track endogenous antigen-specific follicular helper T cells by flow cytometry after protein vaccination in nonmodified wild-type animals, which ultimately provides a comprehensive way to enumerate, characterize, and isolate these particular cells in vivo.

  20. An MHC-restricted antibody-based chimeric antigen receptor requires TCR-like affinity to maintain antigen specificity

    Directory of Open Access Journals (Sweden)

    Marcela V Maus

    2016-01-01

    Full Text Available Chimeric antigen receptors (CARs are synthetic receptors that usually redirect T cells to surface antigens independent of human leukocyte antigen (HLA. Here, we investigated a T cell receptor-like CAR based on an antibody that recognizes HLA-A*0201 presenting a peptide epitope derived from the cancer-testis antigen NY-ESO-1. We hypothesized that this CAR would efficiently redirect transduced T cells in an HLA-restricted, antigen-specific manner. However, we found that despite the specificity of the soluble Fab, the same antibody in the form of a CAR caused moderate lysis of HLA-A2 expressing targets independent of antigen owing to T cell avidity. We hypothesized that lowering the affinity of the CAR for HLA-A2 would improve its specificity. We undertook a rational approach of mutating residues that, in the crystal structure, were predicted to stabilize binding to HLA-A2. We found that one mutation (DN lowered the affinity of the Fab to T cell receptor-range and restored the epitope specificity of the CAR. DN CAR T cells lysed native tumor targets in vitro, and, in a xenogeneic mouse model implanted with two human melanoma lines (A2+/NYESO+ and A2+/NYESO−, DN CAR T cells specifically migrated to, and delayed progression of, only the HLA-A2+/NY-ESO-1+ melanoma. Thus, although maintaining MHC-restricted antigen specificity required T cell receptor-like affinity that decreased potency, there is exciting potential for CARs to expand their repertoire to include a broad range of intracellular antigens.

  1. Nod2 is required for antigen-specific humoral responses against antigens orally delivered using a recombinant Lactobacillus vaccine platform.

    Directory of Open Access Journals (Sweden)

    Sara A Bumgardner

    Full Text Available Safe and efficacious orally-delivered mucosal vaccine platforms are desperately needed to combat the plethora of mucosally transmitted pathogens. Lactobacillus spp. have emerged as attractive candidates to meet this need and are known to activate the host innate immune response in a species- and strain-specific manner. For selected bacterial isolates and mutants, we investigated the role of key innate immune pathways required for induction of innate and subsequent adaptive immune responses. Co-culture of murine macrophages with L. gasseri (strain NCK1785, L. acidophilus (strain NCFM, or NCFM-derived mutants-NCK2025 and NCK2031-elicited an M2b-like phenotype associated with TH2 skewing and immune regulatory function. For NCFM, this M2b phenotype was dependent on expression of lipoteichoic acid and S layer proteins. Through the use of macrophage genetic knockouts, we identified Toll-like receptor 2 (TLR2, the cytosolic nucleotide-binding oligomerization domain containing 2 (NOD2 receptor, and the inflammasome-associated caspase-1 as contributors to macrophage activation, with NOD2 cooperating with caspase-1 to induce inflammasome derived interleukin (IL-1β in a pyroptosis-independent fashion. Finally, utilizing an NCFM-based mucosal vaccine platform with surface expression of human immunodeficiency virus type 1 (HIV-1 Gag or membrane proximal external region (MPER, we demonstrated that NOD2 signaling is required for antigen-specific mucosal and systemic humoral responses. We show that lactobacilli differentially utilize innate immune pathways and highlight NOD2 as a key mediator of macrophage function and antigen-specific humoral responses to a Lactobacillus acidophilus mucosal vaccine platform.

  2. Focal radiation therapy combined with 4-1BB activation and CTLA-4 blockade yields long-term survival and a protective antigen-specific memory response in a murine glioma model.

    Directory of Open Access Journals (Sweden)

    Zineb Belcaid

    Full Text Available Glioblastoma (GBM is the most common malignant brain tumor in adults and is associated with a poor prognosis. Cytotoxic T lymphocyte antigen -4 (CTLA-4 blocking antibodies have demonstrated an ability to generate robust antitumor immune responses against a variety of solid tumors. 4-1BB (CD137 is expressed by activated T lymphocytes and served as a co-stimulatory signal, which promotes cytotoxic function. Here, we evaluate a combination immunotherapy regimen involving 4-1BB activation, CTLA-4 blockade, and focal radiation therapy in an immune-competent intracranial GBM model.GL261-luciferace cells were stereotactically implanted in the striatum of C57BL/6 mice. Mice were treated with a triple therapy regimen consisted of 4-1BB agonist antibodies, CTLA-4 blocking antibodies, and focal radiation therapy using a small animal radiation research platform and mice were followed for survival. Numbers of brain-infiltrating lymphocytes were analyzed by FACS analysis. CD4 or CD8 depleting antibodies were administered to determine the relative contribution of T helper and cytotoxic T cells in this regimen. To evaluate the ability of this immunotherapy to generate an antigen-specific memory response, long-term survivors were re-challenged with GL261 glioma en B16 melanoma flank tumors.Mice treated with triple therapy had increased survival compared to mice treated with focal radiation therapy and immunotherapy with 4-1BB activation and CTLA-4 blockade. Animals treated with triple therapy exhibited at least 50% long-term tumor free survival. Treatment with triple therapy resulted in a higher density of CD4+ and CD8+ tumor infiltrating lymphocytes. Mechanistically, depletion of CD4+ T cells abrogated the antitumor efficacy of triple therapy, while depletion of CD8+ T cells had no effect on the treatment response.Combination therapy with 4-1BB activation and CTLA-4 blockade in the setting of focal radiation therapy improves survival in an orthotopic mouse

  3. 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.

  4. Preparation and characterization of the polyclonal antibody against ...

    African Journals Online (AJOL)

    To prepare the polyclonal antibody against GAR domain, cDNA encoding 466 amino acids protein of GAR domain was amplified from MG-63 cell by RT-PCR. The amplified cDNA, that exhibited 99% identity to the published sequence, was cloned into prokaryotic expression vector pQE-80L for the expression of GAR ...

  5. Development of polyclonal antibodies for the detection of ...

    African Journals Online (AJOL)

    Development of polyclonal antibodies for the detection of recombinant human erythropoietin. Collares Thaís Farias, Monte Leonardo Garcia, Campos Vinicius Farias, Seixas Fabiana Kömmiling, Collares Tiago Veiras, Dellagostin Odir, Hartleben Cláudia Pinho ...

  6. Induction of an antigen specific gut inflammatory reaction in mice and rats: a model for human Inflammatory Bowel Disease

    Directory of Open Access Journals (Sweden)

    Gerlinde Agate Platais Brasil Teixeira

    2009-06-01

    Full Text Available Food allergy is an adverse reaction that occurs in susceptible people when they eat sensitizing foods and is one of the causes of Inflammatory Bowel Disease (IBD. The effort to understand the induction process of these diseases is important as IBD is increasing worldwide, including in Brazil. The aim of this study was to develop an experimental antigen specific inflammatory process of the gut of mice and rats, using peanut seeds. Animals were immunized with peanut protein extract before their exposure to the in natura peanut seeds. Results showed that systemic immunization with peanut protein extracts rendered significantly higher antibody titers than control groups and that immunized animals submitted to a challenge diet containing peanuts presented time dependent alterations of the gut similar to celiac disease. In conclusion, results suggested that this experimental model was a convenient tool to study the evolution of alterations in chronic antigen specific gut inflammatory process.A alergia alimentar consiste em uma reação adversa que ocorre em pessoas susceptíveis quando ingerem alimentos sensibilizantes, sendo uma das causas das Doenças Inflamatórias Intestinais (IBD. O objetivo deste estudo foi desenvolver um protocolo experimental de indução de um processo inflamatório intestinal antígeno-específico em camundongos e ratos. Foi escolhida para a indução deste processo a semente de amendoim. Os animais foram imunizados com o extrato protéico previamente à exposição com a semente in natura. Nossos resultados mostram que a imunização sistêmica com extratos protéicos de amendoim ocasiona títulos significativamente maiores de anticorpos quando comparado ao grupo controle e que os animais imunizados submetidos ao desafio com a dieta contendo exclusivamente amendoim apresentam alterações intestinais tempo-dependente similares àquelas observadas na doença celíaca. Os resultados obtidos sugerem que este modelo

  7. Antigen-Specific IgG ameliorates allergic airway inflammation via Fcγ receptor IIB on dendritic cells

    Directory of Open Access Journals (Sweden)

    Karasuyama Hajime

    2011-04-01

    Full Text Available Abstract Background There have been few reports on the role of Fc receptors (FcRs and immunoglobulin G (IgG in asthma. The purpose of this study is to clarify the role of inhibitory FcRs and antigen presenting cells (APCs in pathogenesis of asthma and to evaluate antigen-transporting and presenting capacity by APCs in the tracheobronchial mucosa. Methods In FcγRIIB deficient (KO and C57BL/6 (WT mice, the effects of intratracheal instillation of antigen-specific IgG were analysed using the model with sensitization and airborne challenge with ovalbumin (OVA. Thoracic lymph nodes instilled with fluorescein-conjugated OVA were analysed by fluorescence microscopy. Moreover, we analysed the CD11c+ MHC class II+ cells which intaken fluorescein-conjugated OVA in thoracic lymph nodes by flow cytometry. Also, lung-derived CD11c+ APCs were analysed by flow cytometry. Effects of anti-OVA IgG1 on bone marrow dendritic cells (BMDCs in vitro were also analysed. Moreover, in FcγRIIB KO mice intravenously transplanted dendritic cells (DCs differentiated from BMDCs of WT mice, the effects of intratracheal instillation of anti-OVA IgG were evaluated by bronchoalveolar lavage (BAL. Results In WT mice, total cells and eosinophils in BAL fluid reduced after instillation with anti-OVA IgG1. Anti-OVA IgG1 suppressed airway inflammation in hyperresponsiveness and histology. In addition, the number of the fluorescein-conjugated OVA in CD11c+ MHC class II+ cells of thoracic lymph nodes with anti-OVA IgG1 instillation decreased compared with PBS. Also, MHC class II expression on lung-derived CD11c+ APCs with anti-OVA IgG1 instillation reduced. Moreover, in vitro, we showed that BMDCs with anti-OVA IgG1 significantly decreased the T cell proliferation. Finally, we demonstrated that the lacking effects of anti-OVA IgG1 on airway inflammation on FcγRIIB KO mice were restored with WT-derived BMDCs transplanted intravenously. Conclusion Antigen-specific IgG ameliorates

  8. Enhanced Dendritic Cell-Mediated Antigen-Specific CD4+ T Cell Responses: IFN-Gamma Aids TLR Stimulation

    Directory of Open Access Journals (Sweden)

    Kuo-Ching Sheng

    2013-01-01

    Full Text Available Phenotypic maturation and T cell stimulation are two functional attributes of DCs critical for immune induction. The combination of antigens, including those from cancer, with Toll-like receptor (TLR ligands induces far superior cellular immune responses compared to antigen alone. In this study, IFN-gamma treatment of bone marrow-derived DC, followed by incubation with the TLR2, TLR4, or TLR9 agonists, enhanced DC activation compared to TLR ligation alone. Most notably, the upregulation of CD40 with LPS stimulation and CD86 with CpG stimulation was observed in in vitro cultures. Similarly, IFN-gamma coinjected with TLR ligands was able to promote DC activation in vivo, with DCs migrating from the site of immunization to the popliteal lymph nodes demonstrating increased expression of CD80 and CD86. The heightened DC activation translated to a drastic increase in T cell stimulatory capacity in both antigen independent and antigen dependent fashions. This is the first time that IFN-gamma has been shown to have a combined effect with TLR ligation to enhance DC activation and function. The results demonstrate the novel use of IFN-gamma together with TLR agonists to enhance antigen-specific T cell responses, for applications in the development of enhanced vaccines and drug targets against diseases including cancer.

  9. Effect of operating conditions in production of diagnostic Salmonella Enteritidis O-antigen-specific monoclonal antibody in different bioreactor systems.

    Science.gov (United States)

    Ayyildiz-Tamis, Duygu; Nalbantsoy, Ayse; Elibol, Murat; Deliloglu-Gurhan, Saime Ismet

    2014-01-01

    In this study, different cultivation systems such as roller bottles (RB), 5-L stirred-tank bioreactor (STR), and disposable bioreactors were used to cultivate hybridoma for lab-scale production of Salmonella Enteritidis O-antigen-specific monoclonal antibody (MAb). Hybridoma cell line was cultivated in either serum-containing or serum-free medium (SFM) culture conditions. In STR, MAb production scaled up to 4 L, and production capabilities of the cells were also evaluated in different featured production systems. Moreover, the growth parameters of the cells in all production systems such as glucose consumption, lactate and ammonia production, and also MAb productivities were determined. Collected supernatants from the reactors were concentrated by a cross-flow filtration system. In conclusion, cells were not adapted to SFM in RB and STR. Therefore, less MAb titer in both STR and RB systems with SFM was observed compared to the cultures containing fetal bovine serum-supplemented medium. A higher MAb titer was gained in the membrane-aerated system compared to those in STR and RB. Although the highest MAb titer was obtained in the static membrane bioreactor system, the highest productivity was obtained in STR operated in semicontinuous mode with overlay aeration.

  10. Splenic B cells and antigen-specific B cells process anti-Ig in a similar manner

    International Nuclear Information System (INIS)

    Myers, C.D.; Vitetta, E.S.

    1989-01-01

    B lymphocytes can process and present antigen to T cells. However, the fate of native antigen after its binding to specific B cells, i.e., the intracellular events involved in the processing and recycling of the antigenic fragments to the cell surface for antigen presentation, are not well understood. In the present study, we demonstrate that murine B cells degrade anti-Ig molecules bound to their surface and release acid soluble fragments into the supernatant. We also demonstrate that the kinetics of this process are identical for anti-mu, anti-delta, and anti-light chain antibodies, indicating that both surface IgM and surface IgD are equally effective in binding antigen and directing its processing. We also describe the effects of azide, chloroquine, and irradiation on this process. To extend these studies to the processing of specifically bound antigen, we demonstrate that highly purified trinitrophenyl antigen-binding cells degrade anti-Ig molecules with the same kinetics as unpurified splenic B cells. Thus, this purified population provides a suitable model system for the analysis of antigen degradation by antigen-specific cells

  11. Antigen-specific IL-23/17 pathway activation by murine semi-mature DC-like cells

    Energy Technology Data Exchange (ETDEWEB)

    Nagasaka, Shinya; Iwasaki, Takumi; Okano, Tomoko [Department of Biological Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510 (Japan); Chiba, Joe, E-mail: chibaj@rs.noda.tus.ac.jp [Department of Biological Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510 (Japan)

    2009-09-11

    We analyzed the phenotype and function of bone marrow-derived dendritic cells (DCs) induced in vitro without using any serum during the late stage of cultivation. These 'serum-free' DCs (SF-DCs) possessed the ability to induce T cell proliferation as well as antibody responses, indicating that they were functional DCs. Surprisingly, the SF-DCs akin to semi-mature DCs in terms of both phenotypic and functional characteristics. The SF-DCs did not produce IL-12 but produced large amounts of IL-23 following lipopolysaccharide stimulation. The antigen-specific production of IL-17 by CD4{sup +} T cells co-cultured with OVA-loaded SF-DCs was significantly higher than that with OVA-loaded conventional DCs. These results suggest that SF-DCs tend to produce IL-23 and can consequently induce the IL-17 producing CD4{sup +} T cells. The semi-mature DC-like cells reported here will be useful vehicles for DC immunization and might contribute to studies on the possible involvement of semi-mature DCs in Th17 cell differentiation.

  12. Fluorescently labeled dengue viruses as probes to identify antigen-specific memory B cells by multiparametric flow cytometry.

    Science.gov (United States)

    Woda, Marcia; Mathew, Anuja

    2015-01-01

    Low frequencies of memory B cells in the peripheral blood make it challenging to measure the functional and phenotypic characteristics of this antigen experienced subset of B cells without in vitro culture. To date, reagents are lacking to measure ex vivo frequencies of dengue virus (DENV)-specific memory B cells. We wanted to explore the possibility of using fluorescently labeled DENV as probes to detect antigen-specific memory B cells in the peripheral blood of DENV immune individuals. Alexa Fluor dye-labeled DENV yielded viable virus that could be stored at -80°C for long periods of time. Using a careful gating strategy and methods to decrease non-specific binding, we were able to identify a small frequency of B cells from dengue immune individuals that bound labeled DENV. Sorted DENV(+) B cells from immune, but not naïve donors secreted antibodies that bound DENV after in vitro stimulation. Overall, Alexa Fluor dye-labeled DENVs are useful reagents to enable the detection and characterization of memory B cells in DENV immune individuals. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Enumeration of antigen-specific CD8+ T lymphocytes by single-platform, HLA tetramer-based flow cytometry: a European multicenter evaluation.

    NARCIS (Netherlands)

    Heijnen, I.; Barnett, D.; Arroz, M.J.; Barry, S.M.; Bonneville, M.; Brando, B.; D'Hautcourt, J.L.; Kern, F.; Totterman, T.H.; Marijt, E.W.; Bossy, D.; Preijers, F.W.M.B.; Rothe, G.; Gratama, J.W.

    2004-01-01

    BACKGROUND: HLA class I peptide tetramers represent powerful diagnostic tools for detection and monitoring of antigen-specific CD8(+) T cells. The impetus for the current multicenter study is the critical need to standardize tetramer flow cytometry if it is to be implemented as a routine diagnostic

  14. The simultaneous ex vivo detection of low-frequency antigen-specific CD4+ and CD8+ T-cell responses using overlapping peptide pools.

    Science.gov (United States)

    Singh, Satwinder Kaur; Meyering, Maaike; Ramwadhdoebe, Tamara H; Stynenbosch, Linda F M; Redeker, Anke; Kuppen, Peter J K; Melief, Cornelis J M; Welters, Marij J P; van der Burg, Sjoerd H

    2012-11-01

    The ability to measure antigen-specific T cells at the single-cell level by intracellular cytokine staining (ICS) is a promising immunomonitoring tool and is extensively applied in the evaluation of immunotherapy of cancer. The protocols used to detect antigen-specific CD8+ T-cell responses generally work for the detection of antigen-specific T cells in samples that have undergone at least one round of in vitro pre-stimulation. Application of a common protocol but now using long peptides as antigens was not suitable to simultaneously detect antigen-specific CD8+ and CD4+ T cells directly ex vivo in cryopreserved samples. CD8 T-cell reactivity to monocytes pulsed with long peptides as antigens ranged between 5 and 25 % of that observed against monocytes pulsed with a direct HLA class I fitting minimal CTL peptide epitope. Therefore, we adapted our ICS protocol and show that the use of tenfold higher concentration of long peptides to load APC, the use of IFN-α and poly(I:C) to promote antigen processing and improve T-cell stimulation, does allow for the ex vivo detection of low-frequency antigen-specific CD8+ and CD4+ T cells in an HLA-independent setting. While most of the improvements were related to increasing the ability to measure CD8+ T-cell reactivity following stimulation with long peptides to at least 50 % of the response detected when using a minimal peptide epitope, the final analysis of blood samples from vaccinated patients successfully showed that the adapted ICS protocol also increases the ability to ex vivo detect low-frequency p53-specific CD4+ T-cell responses in cryopreserved PBMC samples.

  15. Longitudinal multiparameter single-cell analysis of macaques immunized with pneumococcal protein-conjugated or unconjugated polysaccharide vaccines reveals distinct antigen specific memory B cell repertoires.

    Directory of Open Access Journals (Sweden)

    Bin Jia

    Full Text Available The efficacy of protein-conjugated pneumococcal polysaccharide vaccines has been well characterized for children. The level of protection conferred by unconjugated polysaccharide vaccines remains less clear, particularly for elderly individuals who have had prior antigenic experience through immunization with unconjugated polysaccharide vaccines or natural exposure to Streptococcus pneumoniae.We compared the magnitude, diversity and genetic biases of antigen-specific memory B cells in two groups of adult cynomolgus macaques that were immunized with a 7-valent conjugated vaccine and boosted after five years with either a 13-valent pneumococcal polysaccharide conjugate vaccine (13vPnC or a 23-valent unconjugated pneumococcal polysaccharide vaccine (23vPS using microengraving (a single-cell analysis method and single-cell RT-PCR.Seven days after boosting, the mean frequency of antigen-specific memory B cells was significantly increased in macaques vaccinated with 13vPnC compared to those receiving 23vPS. The 13vPnC-vaccinated macaques also exhibited a more even distribution of antibody specificities to four polysaccharides in the vaccine (PS4, 6B, 14, 23F that were examined. However, single-cell analysis of the antibody variable region sequences from antigen-specific B cells elicited by unconjugated and conjugated vaccines indicated that both the germline gene segments forming the heavy chains and the average lengths of the Complementary Determining Region 3 (CDR3 were similar.Our results confirm that distinctive differences can manifest between antigen-specific memory B cell repertoires in nonhuman primates immunized with conjugated and unconjugated pneumococcal polysaccharide vaccines. The study also supports the notion that the conjugated vaccines have a favorable profile in terms of both the frequency and breadth of the anamnestic response among antigen-specific memory B cells.

  16. An inducible model of abacterial prostatitis induces antigen specific inflammatory and proliferative changes in the murine prostate

    Science.gov (United States)

    Haverkamp, Jessica M.; Charbonneau, Bridget; Meyerholz, David K.; Cohen, Michael B.; Snyder, Paul W.; Svensson, Robert U.; Henry, Michael D.; Wang, Hsing- Hui

    2011-01-01

    Background Prostatitis is a poorly understood disease and increasing evidence suggests inflammation is involved in other prostatic diseases, including prostate cancer. Methods The ability of pre-activated CD8 T cells to induce prostatitis was examined by adoptive transfer into POET-3 mice or POET-3/Luc/Pten−/+ mice. Characterization of the inflammatory response was determined by examining leukocyte infiltration by histological analysis, flow cytometry and by evaluating cytokine and chemokine levels in prostate tissue. The impact of inflammation on the prostate was evaluated by monitoring epithelial cell proliferation over time. Results Initiation of inflammation by ovalbumin specific CD8+ T cells (OT-I cells) resulted in development of acute prostatitis in the anterior, dorsolateral and anterior prostate of POET-3 and POET-3/Luc/Pten−/+ mice. Acute prostatitis was characterized by recruitment of adoptively transferred OT-I cells and importantly, autologous CD4+ and CD8+ T cells, myeloid-derived suppressor cells (MDSC) and regulatory T cells (Treg). In concert with leukocyte infiltration elevated levels of pro-inflammatory cytokines and chemokines were observed. Inflammation also resulted in marked epithelial cell proliferation that was sustained up to 80 days post adoptive-transfer of OT-I cells. Conclusions The POET-3 model represents a novel mouse model to study both acute and chronic prostate inflammation in an antigen-specific system. Further, the POET-3 mouse model can be crossed with other genetic models of disease such as the C57/Luc/Pten−/− model of prostate cancer, allowing the impact of prostatitis on other prostatic diseases to be evaluated. PMID:21656824

  17. Antigen specific T-cell responses against tumor antigens are controlled by regulatory T cells in patients with prostate cancer.

    Science.gov (United States)

    Hadaschik, Boris; Su, Yun; Huter, Eva; Ge, Yingzi; Hohenfellner, Markus; Beckhove, Philipp

    2012-04-01

    Immunotherapy is a promising approach in an effort to control castration resistant prostate cancer. We characterized tumor antigen reactive T cells in patients with prostate cancer and analyzed the suppression of antitumor responses by regulatory T cells. Peripheral blood samples were collected from 57 patients with histologically confirmed prostate cancer, 8 patients with benign prostatic hyperplasia and 16 healthy donors. Peripheral blood mononuclear cells were isolated and antigen specific interferon-γ secretion of isolated T cells was analyzed by enzyme-linked immunospot assay. T cells were functionally characterized and T-cell responses before and after regulatory T-cell depletion were compared. As test tumor antigens, a panel of 11 long synthetic peptides derived from a total of 8 tumor antigens was used, including prostate specific antigen and prostatic acid phosphatase. In patients with prostate cancer we noted a 74.5% effector T-cell response rate compared with only 25% in patients with benign prostatic hyperplasia and 31% in healthy donors. In most patients 2 or 3 tumor antigens were recognized. Comparing various disease stages there was a clear increase in the immune response against prostate specific antigens from intermediate to high risk tumors and castration resistant disease. Regulatory T-cell depletion led to a significant boost in effector T-cell responses against prostate specific antigen and prostatic acid phosphatase. Tumor specific effector T cells were detected in most patients with prostate cancer, especially those with castration resistant prostate cancer. Since effector T-cell responses against prostate specific antigens strongly increased after regulatory T-cell depletion, our results indicate that immunotherapy efficacy could be enhanced by decreasing regulatory T cells. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  18. Correlation between CD16a binding and immuno effector functionality of an antigen specific immunoglobulin Fc fragment (Fcab).

    Science.gov (United States)

    Kainer, Manuela; Antes, Bernhard; Wiederkum, Susanne; Wozniak-Knopp, Gordana; Bauer, Anton; Rüker, Florian; Woisetschläger, Max

    2012-10-15

    Antigen binding immunoglobulin Fc fragments (Fcab) are generated by engineering loop regions in the CH3 domain of human IgG1 Fc. Variants of an Fcab specific for Her-2 were designed to display either enhanced (S239D:A330L:I332E) or diminished (L234A:L235A) binding affinities to the Fc receptor CD16a based on mutations described previously. The two mutant Fcab proteins demonstrated the expected modulation of CD16a binding. Interaction with recombinant or cell surface expressed Her-2 was unaffected in both mutants compared to the parental Fcab. Binding affinities for CD16a correlated with the ADCC-potencies of the Fcab variants. Additional studies indicated that the L234A:L235A variant Fcab had equivalent structural features as the unmodified Fcab since their DSC profiles were similar and antigen binding after re-folding upon partial heat denaturation had not changed. Introduction of the S239D:A330L:I332E mutations resulted in a significant reduction of the CH2 domain melting temperature, a moderate decrease of the thermal transition of the CH3 domain and lower antigen binding after thermal stress compared to the parental Fcab. We conclude that the known correlation between CD16a binding affinity and ADCC potency is also valid in Fcab proteins and that antigen specific Fcab molecules can be further engineered for fine tuning of immuno effector functions. Copyright © 2012 Elsevier Inc. All rights reserved.

  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

    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. Lack of protection following passive transfer of polyclonal highly functional low-dose non-neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Anne-Sophie Dugast

    Full Text Available Recent immune correlates analysis from the RV144 vaccine trial has renewed interest in the role of non-neutralizing antibodies in mediating protection from infection. While neutralizing antibodies have proven difficult to induce through vaccination, extra-neutralizing antibodies, such as those that mediate antibody-dependent cellular cytotoxicity (ADCC, are associated with long-term control of infection. However, while several non-neutralizing monoclonal antibodies have been tested for their protective efficacy in vivo, no studies to date have tested the protective activity of naturally produced polyclonal antibodies from individuals harboring potent ADCC activity. Because ADCC-inducing antibodies are highly enriched in elite controllers (EC, we passively transferred highly functional non-neutralizing polyclonal antibodies, purified from an EC, to assess the potential impact of polyclonal non-neutralizing antibodies on a stringent SHIV-SF162P3 challenge in rhesus monkeys. Passive transfer of a low-dose of ADCC inducing antibodies did not protect from infection following SHIV-SF162P3 challenge. Passively administered antibody titers and gp120-specific, but not gp41-specific, ADCC and antibody induced phagocytosis (ADCP were detected in the majority of the monkeys, but did not correlate with post infection viral control. Thus these data raise the possibility that gp120-specific ADCC activity alone may not be sufficient to control viremia post infection but that other specificities or Fc-effector profiles, alone or in combination, may have an impact on viral control and should be tested in future passive transfer experiments.

  1. Antigen-Specific lgA B Memory Cell Responses to Shigella Antigens Elicited in Volunteers Immunized with Live Attenuated Shigella flexneri 2a Oral Vaccine Candidates

    Science.gov (United States)

    2011-01-01

    167. [10] E.V. Oaks, T.L. Hale, S.B. Formal, Serum immune response to Shigella protein antigens in rhesus monkeys and humans infected with Shigella ...cell responses to Shigella antigens elicited in volunteers immunized with live attenuated Shigella flexneri 2a oral vaccine candidates J.K. Simona,b... Shigella ;. B cell memory; Immunoglobulin lgA; Mucosal immunity Abstract We studied the induction of antigen-specific lgA memory B cells (BM) in

  2. NOG-hIL-4-Tg, a new humanized mouse model for producing tumor antigen-specific IgG antibody by peptide vaccination.

    Directory of Open Access Journals (Sweden)

    Yoshie Kametani

    Full Text Available Immunodeficient mice transplanted with human peripheral blood mononuclear cells (PBMCs are promising tools to evaluate human immune responses to vaccines. However, these mice usually develop severe graft-versus-host disease (GVHD, which makes estimation of antigen-specific IgG production after antigen immunization difficult. To evaluate antigen-specific IgG responses in PBMC-transplanted immunodeficient mice, we developed a novel NOD/Shi-scid-IL2rγnull (NOG mouse strain that systemically expresses the human IL-4 gene (NOG-hIL-4-Tg. After human PBMC transplantation, GVHD symptoms were significantly suppressed in NOG-hIL-4-Tg compared to conventional NOG mice. In kinetic analyses of human leukocytes, long-term engraftment of human T cells has been observed in peripheral blood of NOG-hIL-4-Tg, followed by dominant CD4+ T rather than CD8+ T cell proliferation. Furthermore, these CD4+ T cells shifted to type 2 helper (Th2 cells, resulting in long-term suppression of GVHD. Most of the human B cells detected in the transplanted mice had a plasmablast phenotype. Vaccination with HER2 multiple antigen peptide (CH401MAP or keyhole limpet hemocyanin (KLH successfully induced antigen-specific IgG production in PBMC-transplanted NOG-hIL-4-Tg. The HLA haplotype of donor PBMCs might not be relevant to the antibody secretion ability after immunization. These results suggest that the human PBMC-transplanted NOG-hIL-4-Tg mouse is an effective tool to evaluate the production of antigen-specific IgG antibodies.

  3. Antigen-specific tolerance inhibits autoimmune uveitis in pre-sensitized animals by deletion and CD4+CD25+ T-regulatory cells.

    Science.gov (United States)

    Matta, Bharati; Jha, Purushottam; Bora, Puran S; Bora, Nalini S

    2010-02-01

    The objective of this study was to inhibit experimental autoimmune anterior uveitis (EAAU) by establishing antigen-specific immune tolerance in animals pre-sensitized with melanin-associated antigen (MAA). Intravenous administration of MAA on days 6, 7, 8 and 9 post-immunization induced tolerance and inhibited EAAU in all Lewis rats. The number of cells (total T cells, CD4(+) T cells and CD8(+) T cells) undergoing apoptosis dramatically increased in the popliteal lymph nodes (LNs) of the tolerized animals compared with non-tolerized animals. In addition, Fas ligand (FasL), TNF receptor 1 (TNFR1) and caspase-8 were upregulated in tolerized rats. Proliferation of total lymphocytes, CD4(+)T cells and CD8(+) T cells (harvested from the popliteal LNs) in response to antigenic stimulation was drastically reduced in the state of tolerance compared with the cells from non-tolerized animals. The level of interferon (IFN)-gamma and IL-2 decreased, whereas TGF-beta2 was elevated in the state of tolerance. Furthermore, the number of CD4(+)CD25(+)FoxP3(+) regulatory T cells (Tregs) increased in the popliteal LNs of tolerized animals compared with non-tolerized animals. In conclusion, our results suggest that deletion of antigen-specific T cells by apoptosis and active suppression mediated by Tregs has an important role in the induction of antigen specific immune tolerance in animals with an established immune response against MAA.

  4. Synthesis of Polyclonal Antibodies against Aflatoxin B1

    Directory of Open Access Journals (Sweden)

    Wiyogo Prio Wicaksono

    2015-09-01

    Full Text Available Polyclonal antibodies of aflatoxin B1 were successfully produced from New Zealand White female rabbits after immunization by the hapten of aflatoxin B1-carboxymethyl hydroxylamine hemihydrochloride (AFB1-CMO conjugated with bovine serum albumin (BSA as the antigen. The hapten was synthesized using the carbodiimide method with CMO as a linker. Absorption peaks at 362, 264, and 218 nm were observed as a result of characterization with UV-Vis spectroscopy, while IR spectroscopy showed peaks at 3448 cm-1 and 1642 cm-1 attributable to the hydroxyl and nitrile groups, respectively. Furthermore, mass spectrometry showed fragmentation at the m/z of 386, 368.2, and 310, which confirms that the hapten of AFB1-CMO was successfully synthesized. The hapten was then conjugated with BSA to serve as an antigen of AFB1 when it was injected into the rabbits. The specificity of the antigen towards its antibody and the confirmation of hapten-BSA conjugation were characterized using the dot blot immunoassay, which showed a BSA concentration of 1.74 mg/mL. Two weeks after the primary immunization by its antigen, agar gel precipitation testing showed that the rabbit blood serum had positive results for polyclonal antibodiest against AFB1 with the highest concentration of antibodiest of 2.19 mg/mL.

  5. Polyclonal antibody to ovomucoid determination in gamma irradiated laying eggs

    International Nuclear Information System (INIS)

    Harder, Marcia N.C.; Arthur, Valter; Silva, Lucia C.A.S.; Lopes, Tatiana G.G.; Duarte, Keila M.R.; Canniatti-Brazaca, Solange G.; Savino, Vicente J.M.; Coelho, Antonio A.D.

    2009-01-01

    To determine allergenic food proteins, one of the most used tests is the immunoassays such as ELISA (enzyme linked immunosorbent assay), where the antibody recognizes the antigen and this connection is showed by an enzymatic system, in other words, optical density. The aim of this study was to determine the polyclonal antibody efficiency, produced in laboratory, to identify the presence the ovomucoid antigen in treated eggs by gamma irradiation for its inactivation. To evaluate the treatments, polyclonal antibody was produced in female rabbits immunized with bioconjugated ovomucoid. Was used Freund Complete Adjuvant at first immunization and PBS Buffer at four subsequently immunizations every fifteen days, plus a booster 48 hours before the blood retreated. The blood serum was tittered by PTA-ELISA (Plate trapped antigen). All procedures were according to European Norms for ethical and animal welfare. It was used, in nature, commercial laying eggs. So the samples were submitted to the gamma radiation coming from a source of Co 60 , type Multipurpose, under a dose rate of 19.4 and 31.8 Gy/hour, in the doses: 0 (control); 10 KGy; 20 KGy and 30 KGy, in all rates. By the ELISA.s test we can find the egg allergen ovomucoid and the radiation treatment do not showed considerable changes. So we can concluded that the antibody produced is capable of identify the ovomucoid allergenic protein and the gamma irradiation in such rates does not shows changes in that protein, therefore showed some changes in the color and visual viscosity of the egg samples. (author)

  6. Polyclonal antibody to ovomucoid determination in gamma irradiated laying eggs

    Energy Technology Data Exchange (ETDEWEB)

    Harder, Marcia N.C.; Arthur, Valter; Silva, Lucia C.A.S.; Lopes, Tatiana G.G. [Centro de Energia Nuclear na Agricultura (CENA/USP, Piracicaba, SP. Dept. de Radiobiologia e Ambiente) (Brazil)], e-mail: mnharder@cena.usp.br, e-mail: arthur@cena.usp.br, e-mail: tgglopes@cena.usp.br; Duarte, Keila M.R. [Instituto de Zootecnia (IZ . Nova Odessa), Nova Odessa, SP (Brazil)], e-mail: keila@iz.sp.gov.br; Canniatti-Brazaca, Solange G.; Savino, Vicente J.M.; Coelho, Antonio A.D. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil)], e-mail: sgcbraza@esalq.usp.br, e-mail: vjmsavin@esalq.usp.br, e-mail: aadcoelh@esalq.usp.br

    2009-07-01

    To determine allergenic food proteins, one of the most used tests is the immunoassays such as ELISA (enzyme linked immunosorbent assay), where the antibody recognizes the antigen and this connection is showed by an enzymatic system, in other words, optical density. The aim of this study was to determine the polyclonal antibody efficiency, produced in laboratory, to identify the presence the ovomucoid antigen in treated eggs by gamma irradiation for its inactivation. To evaluate the treatments, polyclonal antibody was produced in female rabbits immunized with bioconjugated ovomucoid. Was used Freund Complete Adjuvant at first immunization and PBS Buffer at four subsequently immunizations every fifteen days, plus a booster 48 hours before the blood retreated. The blood serum was tittered by PTA-ELISA (Plate trapped antigen). All procedures were according to European Norms for ethical and animal welfare. It was used, in nature, commercial laying eggs. So the samples were submitted to the gamma radiation coming from a source of Co{sup 60}, type Multipurpose, under a dose rate of 19.4 and 31.8 Gy/hour, in the doses: 0 (control); 10 KGy; 20 KGy and 30 KGy, in all rates. By the ELISA.s test we can find the egg allergen ovomucoid and the radiation treatment do not showed considerable changes. So we can concluded that the antibody produced is capable of identify the ovomucoid allergenic protein and the gamma irradiation in such rates does not shows changes in that protein, therefore showed some changes in the color and visual viscosity of the egg samples. (author)

  7. 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.

  8. Generation of Recombinant Monoclonal Antibodies from Immunised Mice and Rabbits via Flow Cytometry and Sorting of Antigen-Specific IgG+ Memory B Cells.

    Directory of Open Access Journals (Sweden)

    Dale O Starkie

    Full Text Available Single B cell screening strategies, which avoid both hybridoma fusion and combinatorial display, have emerged as important technologies for efficiently sampling the natural antibody repertoire of immunized animals and humans. Having access to a range of methods to interrogate different B cell subsets provides an attractive option to ensure large and diverse panels of high quality antibody are produced. The generation of multiple antibodies and having the ability to find rare B cell clones producing IgG with unique and desirable characteristics facilitates the identification of fit-for-purpose molecules that can be developed into therapeutic agents or research reagents. Here, we describe a multi-parameter flow cytometry single-cell sorting technique for the generation of antigen-specific recombinant monoclonal antibodies from single IgG+ memory B cells. Both mouse splenocytes and rabbit PBMC from immunised animals were used as a source of B cells. Reagents staining both B cells and other unwanted cell types enabled efficient identification of class-switched IgG+ memory B cells. Concurrent staining with antigen labelled separately with two spectrally-distinct fluorophores enabled antigen-specific B cells to be identified, i.e. those which bind to both antigen conjugates (double-positive. These cells were then typically sorted at one cell per well using FACS directly into a 96-well plate containing reverse transcriptase reaction mix. Following production of cDNA, PCR was performed to amplify cognate heavy and light chain variable region genes and generate transcriptionally-active PCR (TAP fragments. These linear expression cassettes were then used directly in a mammalian cell transfection to generate recombinant antibody for further testing. We were able to successfully generate antigen-specific recombinant antibodies from both the rabbit and mouse IgG+ memory B cell subset within one week. This included the generation of an anti-TNFR2 blocking

  9. Enumeration of antigen-specific CD8+ T lymphocytes by single-platform, HLA tetramer-based flow cytometry: a European multicenter evaluation.

    Science.gov (United States)

    Heijnen, Ingmar A F M; Barnett, David; Arroz, Maria J; Barry, Simon M; Bonneville, Marc; Brando, Bruno; D'hautcourt, Jean-Luc; Kern, Florian; Tötterman, Thomas H; Marijt, Erik W A; Bossy, David; Preijers, Frank W M B; Rothe, Gregor; Gratama, Jan W

    2004-11-01

    HLA class I peptide tetramers represent powerful diagnostic tools for detection and monitoring of antigen-specific CD8(+) T cells. The impetus for the current multicenter study is the critical need to standardize tetramer flow cytometry if it is to be implemented as a routine diagnostic assay. Hence, the European Working Group on Clinical Cell Analysis set out to develop and evaluate a single-platform tetramer-based method that used cytomegalovirus (CMV) as the antigenic model. Absolute numbers of CMV-specific CD8(+) T cells were obtained by combining the percentage of tetramer-binding cells with the absolute CD8(+) T-cell count. Six send-outs of stabilized blood from healthy individuals or CMV-carrying donors with CMV-specific CD8(+) T-cell counts of 3 to 10 cells/microl were distributed to 7 to 16 clinical sites. These sites were requested to enumerate CD8(+) T cells and, in the case of CMV-positive donors, CMV-specific subsets on three separate occasions using the standard method. Between-site coefficients of variation of less than 10% (absolute CD8(+) T-cell counts) and approximately 30% (percentage and absolute numbers of CMV-specific CD8(+) T cells) were achieved. Within-site coefficients of variation were approximately 5% (absolute CD8(+) T-cell counts), approximately 9% (percentage CMV-specific CD8(+) T cells), and approximately 17% (absolute CMV-specific CD8(+) T-cell counts). The degree of variation tended to correlate inversely with the proportion of CMV-specific CD8(+) T-cell subsets. The single-platform MHC tetramer-based method for antigen-specific CD8(+) T-cell counting has been evaluated by a European group of laboratories and can be considered a reproducible assay for routine enumeration of antigen-specific CD8(+) T cells. (c) 2004 Wiley-Liss, Inc.

  10. Direct visualization of antigen-specific T cells: HTLV-1 Tax11-19- specific CD8(+) T cells are activated in peripheral blood and accumulate in cerebrospinal fluid from HAM/TSP patients.

    Science.gov (United States)

    Greten, T F; Slansky, J E; Kubota, R; Soldan, S S; Jaffee, E M; Leist, T P; Pardoll, D M; Jacobson, S; Schneck, J P

    1998-06-23

    Human T lymphotropic virus type 1 (HTLV-1) -associated myelopathy/tropic spastic paraparesis is a demyelinating inflammatory neurologic disease associated with HTLV-1 infection. HTLV-1 Tax11-19-specific cytotoxic T cells have been isolated from HLA-A2-positive patients. We have used a peptide-loaded soluble HLA-A2-Ig complex to directly visualize HTLV-1 Tax11-19-specific T cells from peripheral blood and cerebrospinal fluid without in vitro stimulation. Five of six HTLV-1-associated myelopathy/tropic spastic paraparesis patients carried a significant number (up to 13.87%) of CD8(+) lymphocytes specific for the HTLV-1 Tax11-19 peptide in their peripheral blood, which were not found in healthy controls. Simultaneous comparison of peripheral blood and cerebrospinal fluid from one patient revealed 2.5-fold more Tax11-19-specific T cells in the cerebrospinal fluid (23.7% vs. 9.4% in peripheral blood lymphocyte). Tax11-19-specific T cells were seen consistently over a 9-yr time course in one patient as far as 19 yrs after the onset of clinical symptoms. Further analysis of HTLV-1 Tax11-19-specific CD8(+) T lymphocytes in HAM/TSP patients showed different expression patterns of activation markers, intracellular TNF-alpha and gamma-interferon depending on the severity of the disease. Thus, visualization of antigen-specific T cells demonstrates that HTLV-1 Tax11-19-specific CD8(+) T cells are activated, persist during the chronic phase of the disease, and accumulate in cerebrospinal fluid, showing their pivotal role in the pathogenesis of this neurologic disease.

  11. Strong and multi-antigen specific immunity by hepatitis B core antigen (HBcAg)-based vaccines in a murine model of chronic hepatitis B: HBcAg is a candidate for a therapeutic vaccine against hepatitis B virus.

    Science.gov (United States)

    Akbar, Sheikh Mohammad Fazle; Chen, Shiyi; Al-Mahtab, Mamun; Abe, Masanori; Hiasa, Yoichi; Onji, Morikazu

    2012-10-01

    Experimental evidence suggests that hepatitis B core antigen (HBcAg)-specific cytotoxic T lymphocytes (CTL) are essential for the control of hepatitis B virus (HBV) replication and prevention of liver damage in patients with chronic hepatitis B (CHB). However, most immune therapeutic approaches in CHB patients have been accomplished with hepatitis B surface antigen (HBsAg)-based prophylactic vaccines with unsatisfactory clinical outcomes. In this study, we prepared HBsAg-pulsed dendritic cells (DC) and HBcAg-pulsed DC by culturing spleen DC from HBV transgenic mice (HBV TM) and evaluated the immunomodulatory capabilities of these antigens, which may serve as a better therapy for CHB. The kinetics of HBsAg, antibody levels against HBsAg (anti-HBs), proliferation of HBsAg- and HBcAg-specific lymphocytes, production of antigen-specific CTL, and activation of endogenous DC were compared between HBV TM vaccinated with either HBsAg- or HBcAg-pulsed DC. Vaccination with HBsAg-pulsed DC induced HBsAg-specific immunity, but failed to induce HBcAg-specific immunity in HBV TM. However, immunization of HBV TM with HBcAg-pulsed DC resulted in: (1) HBsAg negativity, (2) production of anti-HBs, and (3) development of HBsAg- and HBcAg-specific T cells and CTL in the spleen and the liver. Additionally, significantly higher levels of activated endogenous DC were detected in HBV TM immunized with HBcAg-pulsed DC compared to HBsAg-pulsed DC (pdamage suggests that HBcAg should be an integral component of the therapeutic vaccine against CHB. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Diabetes is associated with lower tuberculosis antigen-specific interferon gamma release in Tanzanian tuberculosis patients and non-tuberculosis controls

    DEFF Research Database (Denmark)

    Faurholt-Jepsen, Daniel; Aabye, Martine Grosos; Jensen, Andreas Vestergaard

    2014-01-01

    in diabetes patients and therefore the validity of interferon gamma release assays (IGRA) may be compromised. The aim of the present study was to assess the association between diabetes and Mycobacterium tuberculosis (Mtb) antigen-specific interferon gamma (IFN-γ) release in a TB endemic area among culture......-confirmed TB patients and non-TB controls. Methods: Culture-confirmed pulmonary TB patients (n = 187) and healthy non-TB neighbourhood controls (n = 190) from Mwanza, Tanzania were tested for the presence of circulating T cells recognizing Mtb antigens using an IGRA. The diabetes status of all participants...

  13. Antiparasitic effects induced by polyclonal IgY antibodies anti-phospholipase A2 from Bothrops pauloensis venom.

    Science.gov (United States)

    Borges, Isabela Pacheco; Silva, Mariana Ferreira; Santiago, Fernanda Maria; de Faria, Lucas Silva; Júnior, Álvaro Ferreira; da Silva, Rafaela José; Costa, Mônica Soares; de Freitas, Vitor; Yoneyama, Kelly Aparecida Geraldo; Ferro, Eloísa Amália Vieira; Lopes, Daiana Silva; Rodrigues, Renata Santos; de Melo Rodrigues, Veridiana

    2018-06-01

    Activities of phospholipases (PLAs) have been linked to pathogenesis in various microorganisms, and implicated in cell invasion and so the interest in these enzymes as potential targets that could contribute to the control of parasite survival and proliferation. Chicken eggs immunized with BnSP-7, a Lys49 phospholipase A 2 (PLA 2 ) homologue from Bothrops pauloensis snake venom, represent an excellent source of polyclonal antibodies with potential inhibitory activity on parasite PLA s. Herein, we report the production, characterization and anti-parasitic effect of IgY antibodies from egg yolks of hens immunized with BnSP-7. Produced antibodies presented increasing avidity and affinity for antigenic toxin epitopes throughout immunization, attaining a plateau after 4weeks. Pooled egg yolks-purified anti-BnSP-7 IgY antibodies were able to specifically recognize different PLA 2 s from Bothrops pauloensis and Bothrops jararacussu venom. Antibodies also neutralized BnSP-7 cytotoxic activity in C2C12 cells. Also, the antibodies recognized targets in Leishmania (Leishmania) amazonensis and Toxoplasma gondii extracts by ELISA and immunofluorescence assays. Anti-BnSP-7 IgY antibodies were cytotoxic to T. gondii tachyzoite and L. (L.) amazonensis promastigotes, and were able to decrease proliferation of both parasites treated before infection. These data suggest that the anti-BnSP-7 IgY is an important tool for discovering new parasite targets and blocking parasitic effects. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Immunoparesis and polyclonal immunoglobulin recovery after auto-SCT for patients with multiple myeloma treated at a single institution.

    Science.gov (United States)

    Jimenez-Zepeda, Victor H; Duggan, Peter; Neri, Paola; Chaudhry, Ahsan; Tay, Jason; Bahlis, Nizar

    2017-11-21

    Immunoparesis and polyclonal immunoglobulin recovery have been recently described as common indicators of immune dysfunction in patients with multiple myeloma. In the present study, we aimed to assess the impact of immunoparesis and polyclonal immunoglobulin recovery at day-100 post autologous stem cell transplant (auto-SCT) on clinical outcomes. A total of 302 patients were included for the analysis of immunoparesis, and 197 were evaluable for polyclonal immunoglobulin recovery evaluation. Immunoparesis was observed in 93.5% of cases, with 47% of cases having polyclonal immunoglobulin recovery at 12 months post auto-SCT. Median overall and progression-free survival were longer in the group of patients with complete or partial normalization of polyclonal immunoglobulins. Patients receiving consolidation had a lower level of polyclonal reconstitution. In conclusion, polyclonal immunoglobulin recovery by 12 months post-auto-SCT is associated with superior overall and progression free survival in patients with MM. Efforts to better enhance polyclonal recovery deserve further investigation.

  15. Pathogenesis of Ovarian Serous Carcinoma as the Basis for Immunologic Directed Diagnosis and Treatment. Project 3 - Development of Antigen-Specific Cancer Vaccines for the Control of Ovarian Cancer

    National Research Council Canada - National Science Library

    Kurman, Robert

    2003-01-01

    The purpose of this study is to test whether the greater extent of intracellular spreading of encoded antigen will generate a higher degree of antigen-specific immunity and ant-tumor effects in vaccinated mice...

  16. Antigen-specific secretion of IFNγ and CXCL10 in whole blood assay detects Mycobacterium leprae infection but does not discriminate asymptomatic infection from symptomatic leprosy.

    Science.gov (United States)

    Hungria, Emerith Mayra; Freitas, Aline Araújo; Pontes, Maria Araci Andrade; Gonçalves, Heitor Sá; Sousa, Ana Lúcia Osório Maroccolo; Costa, Maurício Barcelos; Castilho, Mirian Lane Oliveira Rodrigues; Duthie, Malcolm S; Stefani, Mariane Martins Araújo

    2017-04-01

    To advance toward a whole blood assay (WBA)-based test capable of facilitating the diagnosis of paucibacillary (PB) leprosy, we evaluated a prototype in-tube WBA using combinations of Mycobacterium leprae antigens. Blood was collected from newly diagnosed untreated PB (n=38), multibacillary (MB) (n=30), healthy household contacts (HHC) of MB (n=27), and endemic controls (n=61) residing in Goiânia and Fortaleza, Brazil. Blood was incubated with M. leprae cell sonicate, recombinant proteins (46f+LID-1; ML0276+LID-1), or controls (phosphate-buffered saline, phytohemagglutinin, M. tuberculosis purified protein derivative). Antigen-specific IFNγ production was observed in 71-84% and 55% of PB and HHC, respectively. Antigen-specific CXCL10 levels were similarly assessed to determine if, unlike IFNγ, CXCL10 could differentiate PB from HHC with repeated exposure/asymptomatic M. leprae infection. The CXCL10 levels induced in response to M. leprae antigens could not, however, differentiate PB from HHC. Despite these limitations, the WBAs reported here still represent important tools for assessing M. leprae infection rates and evaluating the impact of control measures. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Production and purification of polyclonal antibody against melatonin hormone

    Directory of Open Access Journals (Sweden)

    Fooladsaz K

    1999-09-01

    Full Text Available Nowadays immunochemical techniques have played a very important and valuable role in quantitative and qualitative assays of liquid compounds of the body. Producing antibody against immunogenes is the first step to make immunochemical kits. In this study production and purification of polyclonal antibody against melatonin has been considered. This hormone which has several important functions in physiological conditions such as migraine, cirrhosis, mammary gland cancer and other diseases, is the most important pineal gland secretion. This gland is a circumventricular organ of brain and according to histological and anatomical studies, it is a high secretory organ, that secretes active biological substances like melatonin, oxytocin, serotonin and ect. In this study, melatonin has been considered as hapten and has become an immunogen by being linked to the bovine serum Albumin. Then, by the immunization of three white New Zeland rabbits that had the booster injections in regular intervals, the antibody titer was detected to be 1/2000, by using checkboard curves, and with the use of melatonin linked to penicillinase as a labeled antigen, the titer was detected 1/200. Finally an antibody with high purification rate has been obtained, which can be used in immunochemical assays like RIA, ELISA, and EIA.

  18. Evaluation of Antigen-Specific IgM and IgG Production during an In Vitro Peripheral Blood Mononuclear Cell Culture Assay

    Directory of Open Access Journals (Sweden)

    Yoshiko Matsuda

    2017-07-01

    Full Text Available The recent attention given to diseases associated with memory B-cell (mBC-produced antibodies (Abs suggests the need for a similar in vitro assay to evaluate the functions of mBCs. Here, we cultured peripheral blood mononuclear cells (PBMCs with the intent to collect mBC-derived Abs in vitro and maintain their cell–cell contact-dependent interactions with helper T-cells. PBMCs were cultured with interleukin (IL-21, CpG-oligodeoxynucleotides (ODN, phorbol myristate acetate (PMA, and phytohemagglutinin/leucoagglutinin (PHA-L in 24-well flat-bottom plates (5 × 105 cells/well. A culture supernatant analysis of PBMCs from healthy donors (n = 10 indicated that antigen-specific IgM Ab levels in a PBMC culture supernatant might be better able to demonstrate the antigen sensitization status in a smaller peripheral blood sample, compared to IgG because Epstein–Barr virus-specific IgM mBCs circulate peripherally at a significantly higher frequency once antiviral humoral immunity has stabilized. Thus, our in vitro assay demonstrated the potential significance of antigen-specific IgM Ab production in the culture supernatants. Furthermore, an analysis of cultured PBMCs from allograft kidney recipients (n = 16 sensitized with de novo donor-specific human leukocyte antigen (HLA-specific Abs (DSAs showed that IgM-type HLA-specific Abs were detected mainly from the culture supernatants from PBMCs of patients with stable graft function, whereas IgG isotype HLA Abs were detectable only from patients with biopsy-proven antibody-mediated rejection. In other words, these IgG isotype Abs also represented an activated humoral immune response in vivo. Additionally, IgM- and IgG-expressing mBCs from healthy donors (n = 5 were cultured with IL-21, CpG-ODN, and a supernatant produced by stimulating CD19+ B-cell-depleted PBMCs with PHA-L and PMA in 24-well flat-bottom plates (1 × 105 cells/well, and the resulting in vitro analysis provided some

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

    Directory of Open Access Journals (Sweden)

    Lynette Beattie

    2010-03-01

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

  20. Growth and yield of mixed polyclonal stands of Populus in short-rotation coppice

    Energy Technology Data Exchange (ETDEWEB)

    Benbrahim, Mohammed; Gavaland, Andre [INRA centre de Toulouse (France). Unite Agroforesterie et foret Paysanne; Gauvin, Jean [INRA centre d' Orleans (France). Unite d' Amelioration des arbres forestiers

    2000-07-01

    Eight clones of poplar were used to compare the growth and productivity of monoclonal and polyclonal mixed plantations in short-rotation coppice. At the end of the eight growing season, the diameter at breast height (DBH) and height of trees were measured and dry weight and yield were estimated. Polyclonal mixtures did not affect mortality. Few differences in growth were observed between clones in monoclonal plots. Polyclonal mixture slightly affected the growth and tree size of the clones compared with monoclonal plots. No increase in stand heterogeneity in relation to clone deployment was observed. A neighbourhood index was calculated for each tree and was significantly affected by polyclonal mixture. However, the relationship between the neighbourhood index and the DBH indicated that this effect did not cause a great change in DBH. Consequently, dry weight and yield productivity were not affected by clone deployment.

  1. Characterization of antigen-specific, Ia-restricted, L3T4+ cytolytic T lymphocytes and assessment of thymic influence on their self specificity

    International Nuclear Information System (INIS)

    Golding, H.; Munitz, T.I.; Singer, A.

    1985-01-01

    The goals of the present study were: (a) to generate antigen-specific L3T4+ cytolytic T lymphocytes (CTL), (b) to determine their major histocompatibility complex (MHC) restriction specificity, and (c) to assess the influence of thymic MHC determinants on their self specificity. The authors found that L3T4+ CTL specific for either trinitrophenyl (TNP)-modified self determinants or minor histocompatibility antigens could be generated from Lyt-2- responder T cells provided that the response cultures were supplemented with supernatants rich in helper factors. Such antigen-specific L3T4+ CTL were Ia-restricted by the criteria that they lysed only Ia+ target cells and that their lysis of Ia+ target cells was specifically inhibited by anti-Ia monoclonal antibodies. The relative frequency of L3T4+ pCTL was found to be only 5-10% of the total anti-TNP pCTL present in the spleens of normal mice. Finally, the authors utilized radiation bone marrow chimeras to assess the influence of the thymic haplotype on the self-Ia specificity of L3T4+ CTL. Both bulk culture and limiting dilution experiments revealed that the self-Ia specificity of L3T4+ anti-TNP CTL from F1----parent and A----B allogeneic chimeras was not markedly skewed toward the haplotype of the chimeric thymus. These results contrast with those obtained previously for L3T4+ anti-TNP Th cells and demonstrate that in the radiation bone marrow chimera model of T cell differentiation, the self specificity of Th cells but not pCTL is markedly influenced by the haplotype of the chimeric thymus

  2. Sequence-Based Discovery Demonstrates That Fixed Light Chain Human Transgenic Rats Produce a Diverse Repertoire of Antigen-Specific Antibodies

    Directory of Open Access Journals (Sweden)

    Katherine E. Harris

    2018-04-01

    Full Text Available We created a novel transgenic rat that expresses human antibodies comprising a diverse repertoire of heavy chains with a single common rearranged kappa light chain (IgKV3-15-JK1. This fixed light chain animal, called OmniFlic, presents a unique system for human therapeutic antibody discovery and a model to study heavy chain repertoire diversity in the context of a constant light chain. The purpose of this study was to analyze heavy chain variable gene usage, clonotype diversity, and to describe the sequence characteristics of antigen-specific monoclonal antibodies (mAbs isolated from immunized OmniFlic animals. Using next-generation sequencing antibody repertoire analysis, we measured heavy chain variable gene usage and the diversity of clonotypes present in the lymph node germinal centers of 75 OmniFlic rats immunized with 9 different protein antigens. Furthermore, we expressed 2,560 unique heavy chain sequences sampled from a diverse set of clonotypes as fixed light chain antibody proteins and measured their binding to antigen by ELISA. Finally, we measured patterns and overall levels of somatic hypermutation in the full B-cell repertoire and in the 2,560 mAbs tested for binding. The results demonstrate that OmniFlic animals produce an abundance of antigen-specific antibodies with heavy chain clonotype diversity that is similar to what has been described with unrestricted light chain use in mammals. In addition, we show that sequence-based discovery is a highly effective and efficient way to identify a large number of diverse monoclonal antibodies to a protein target of interest.

  3. Production and purification of polyclonal antibody against F(ab')2 fragment of human immunoglobulin G

    OpenAIRE

    Nasiri, Hadi; Valedkarimi, Zahra; Aghebati-Maleki, Leili; Abdolalizadeh, Jalal; Kazemi, Tohid; Esparvarinha, Mojghan; Majidi, Jafar

    2017-01-01

    Antibodies are essential tools of biomedical and biochemical researches. Polyclonal antibodies are produced against different epitopes of antigens. Purified F(ab')2 can be used for animal’s immunization to produce polyclonal antibodies. Human immunoglobulin G (IgG) was purified by ion exchange chromatography method. In all stages verification method of the purified antibodies was sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Purified IgG was digested by pepsin enzyme a...

  4. Purification of a polyclonal antibody against CD147 for ELISA using antigen-immunoaffinity chromatography

    Science.gov (United States)

    Liu, Shuangshuang; Li, Shasha; Zhang, Yang; Wang, Ye; Zhu, Yumeng; Wang, Bin; Chen, Zhi-Nan

    2017-01-01

    The immunoglobulin superfamily member CD147 is a widely expressed glycoprotein that occurs in both a membrane-spanning and soluble form. Sandwich ELISA is a powerful tool for analyzing soluble antigens. The aim of the present study was to obtain a highly specific polyclonal antibody against human CD147 that can be used for sandwich ELISA analysis. Expression of recombinant CD147 by a eukaryotic expression system was used to immunize rabbits to obtain antiserum. A highly specific polyclonal antibody that was able to detect soluble CD147 in sandwich ELISA was obtained by antigen-immunoaffinity chromatography purification. The purity of rabbit anti-CD147 polyclonal antibodies was ~99%, and ELISA analysis was able to determine the titer of the rabbit anti-CD147 polyclonal antibodies at 1:512,000. The lowest concentration of the standard CD147 antigen that the sandwich ELISA was able to detect was 31.25 pg/ml. The sandwich ELISA system was composed of anti-hepatoma HAb18 monoclonal antibodies and purified rabbit anti-CD147 polyclonal antibodies. The present study demonstrated that antigen-immunoaffinity chromatography may be a good technique for the purification of polyclonal antibodies, which may be used to detect antigen in sandwich ELISAs. PMID:28487989

  5. 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.

  6. Single-cell multiplexed cytokine profiling of CD19 CAR-T cells reveals a diverse landscape of polyfunctional antigen-specific response.

    Science.gov (United States)

    Xue, Qiong; Bettini, Emily; Paczkowski, Patrick; Ng, Colin; Kaiser, Alaina; McConnell, Timothy; Kodrasi, Olja; Quigley, Máire F; Heath, James; Fan, Rong; Mackay, Sean; Dudley, Mark E; Kassim, Sadik H; Zhou, Jing

    2017-11-21

    It remains challenging to characterize the functional attributes of chimeric antigen receptor (CAR)-engineered T cell product targeting CD19 related to potency and immunotoxicity ex vivo, despite promising in vivo efficacy in patients with B cell malignancies. We employed a single-cell, 16-plex cytokine microfluidics device and new analysis techniques to evaluate the functional profile of CD19 CAR-T cells upon antigen-specific stimulation. CAR-T cells were manufactured from human PBMCs transfected with the lentivirus encoding the CD19-BB-z transgene and expanded with anti-CD3/anti-CD28 coated beads. The enriched CAR-T cells were stimulated with anti-CAR or control IgG beads, stained with anti-CD4 RPE and anti-CD8 Alexa Fluor 647 antibodies, and incubated for 16 h in a single-cell barcode chip (SCBC). Each SCBC contains ~12,000 microchambers, covered with a glass slide that was pre-patterned with a complete copy of a 16-plex antibody array. Protein secretions from single CAR-T cells were captured and subsequently analyzed using proprietary software and new visualization methods. We demonstrate a new method for single-cell profiling of CD19 CAR-T pre-infusion products prepared from 4 healthy donors. CAR-T single cells exhibited a marked heterogeneity of cytokine secretions and polyfunctional (2+ cytokine) subsets specific to anti-CAR bead stimulation. The breadth of responses includes anti-tumor effector (Granzyme B, IFN-γ, MIP-1α, TNF-α), stimulatory (GM-CSF, IL-2, IL-8), regulatory (IL-4, IL-13, IL-22), and inflammatory (IL-6, IL-17A) functions. Furthermore, we developed two new bioinformatics tools for more effective polyfunctional subset visualization and comparison between donors. Single-cell, multiplexed, proteomic profiling of CD19 CAR-T product reveals a diverse landscape of immune effector response of CD19 CAR-T cells to antigen-specific challenge, providing a new platform for capturing CAR-T product data for correlative analysis. Additionally, such high

  7. Generation of HER2 monoclonal antibodies using epitopes of a rabbit polyclonal antibody.

    Science.gov (United States)

    Hu, Francis Jingxin; Uhlen, Mathias; Rockberg, Johan

    2014-01-25

    One of the issues in using polyclonal antibodies is the limited amount of reagent available from an immunisation, leading to batch-to-batch variation and difficulties in obtaining the same antibody performance when the same antigen is re-immunised into several separate animals. This led to the development of hybridoma technology allowing, at least theoretically, for an unlimited production of a specific binder. Nevertheless, polyclonal antibodies are widely used in research and diagnostics and there exists a need for robust methods to convert a polyclonal antibody with good binding performance into a renewable monoclonal with identical or similar binding specificity. Here we have used precise information regarding the functional recognition sequence (epitope) of a rabbit polyclonal antibody with attractive binding characteristics as the basis for generation of a renewable mouse monoclonal antibody. First, the original protein fragment antigen was used for immunisation and generation of mouse hybridoma, without obtaining binders to the same epitope region. Instead a peptide designed using the functional epitope and structural information was synthesised and used for hybridoma production. Several of the monoclonal antibodies generated were found to have similar binding characteristics to those of the original polyclonal antibody. These monoclonal antibodies detected native HER2 on cell lines and were also able to stain HER2 in immunohistochemistry using xenografted mice, as well as human normal and cancer tissues. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. [Preparation and characterization of mouse polyclonal antibody against conserved region of human FOXO3].

    Science.gov (United States)

    Li, Lei; Lyu, Dan

    2017-06-01

    Objective To purify the recombinant protein specific to conserved region of forkhead box O3 (FOXO3) and prepare mouse anti-human FOXO3 polyclonal antibody. Methods The DNA fragment (aa290-472) encoding conserved domain of FOXO3 was amplified by PCR, and subsequently cloned into pET28a vector. Following transformation into E.coli BL21, the soluble fusion protein His-FOXO3 was induced by IPTG and purified by Ni-NTA affinity chromatography. The purified protein was used to immunize BALB/c mice to generate polyclonal antibody. The characteristics of the polyclonal antibody were assessed by ELISA, Western blotting and immunoprecipitation assays. Results We successfully prepared the expression vector pET28a-FOXO3 (aa290-472) and expressed the purified fusion protein in a soluble form. By immunizing mice with the fusion protein, we obtained anti-human FOXO3 polyclonal antibody. ELISA and Western blotting showed that the mouse antibody could recognize specifically the endogenous FOXO3 protein. Conclusion The polyclonal antibody against conserved domain of FOXO3 can identify the endogenous FOXO3 protein. It can be used to analyze the endogenous FOXO3 expression level.

  9. Microneedle-mediated immunization of an adenovirus-based malaria vaccine enhances antigen-specific antibody immunity and reduces anti-vector responses compared to the intradermal route.

    Science.gov (United States)

    Carey, John B; Vrdoljak, Anto; O'Mahony, Conor; Hill, Adrian V S; Draper, Simon J; Moore, Anne C

    2014-08-21

    Substantial effort has been placed in developing efficacious recombinant attenuated adenovirus-based vaccines. However induction of immunity to the vector is a significant obstacle to its repeated use. Here we demonstrate that skin-based delivery of an adenovirus-based malaria vaccine, HAdV5-PyMSP1₄₂, to mice using silicon microneedles induces equivalent or enhanced antibody responses to the encoded antigen, however it results in decreased anti-vector responses, compared to intradermal delivery. Microneedle-mediated vaccine priming and resultant induction of low anti-vector antibody titres permitted repeated use of the same adenovirus vaccine vector. This resulted in significantly increased antigen-specific antibody responses in these mice compared to ID-treated mice. Boosting with a heterologous vaccine; MVA-PyMSP1₄₂ also resulted in significantly greater antibody responses in mice primed with HAdV5-PyMSP1₄₂ using MN compared to the ID route. The highest protection against blood-stage malaria challenge was observed when a heterologous route of immunization (MN/ID) was used. Therefore, microneedle-mediated immunization has potential to both overcome some of the logistic obstacles surrounding needle-and-syringe-based immunization as well as to facilitate the repeated use of the same adenovirus vaccine thereby potentially reducing manufacturing costs of multiple vaccines. This could have important benefits in the clinical ease of use of adenovirus-based immunization strategies.

  10. Antigen-specific T8+ human clone of cells with a nonspecific augmenting function on the T4 cell-B cell helper interaction

    International Nuclear Information System (INIS)

    Brines, R.D.; Sia, D.Y.; Lehner, T.

    1987-01-01

    The authors isolated a T8 + T3 + Ia + clone of cells from the peripheral blood mononuclear cells of a healthy subject. The clone was expanded and maintained with autologous feed cells, interleukin 2, and a streptococcal antigen. The T8 + clone of cells responded specifically to the streptococcal antigen, in the absence of accessory cells,and released a soluble factor. Both the cloned cells and the corresponding soluble factor expressed augmenting helper but not suppressor activity. The augmenting helper activity for B cell antibody synthesis was demonstrable only in the presence of autologous T 4 cells. Radioimmunoassay was used to measure antibodies. Although stimulation of the T8 + cloned cells was antigen-specific, the resulting soluble factor elicited nonspecific antibody synthesis in the presence of T4 and B cells. The T8 + cloned cell-derived factor was adsorbed by B cells but not by T4 cells. Preliminary studies suggest that the factor has the properties of a B cell growth factor. They suggest that the T8 + population consists of functionally heterogeneous cell subsets, some that have suppressor function and others that augment the T4 + helper-inducer activity in B cell antibody synthesis

  11. Clonal analysis of T-cell responses to herpes simplex virus: isolation, characterization and antiviral properties of an antigen-specific helper T-cell clone.

    Science.gov (United States)

    Leung, K N; Nash, A A; Sia, D Y; Wildy, P

    1984-12-01

    A herpes simplex virus (HSV)-specific long-term T-cell clone has been established from the draining lymph node cells of BALB/c mice; the cells required repeated in vitro restimulation with UV-irradiated virus. The established T-cell clone expresses the Thy-1 and Lyt-1+2,3- surface antigens. For optimal proliferation of the cloned cells, both the presence of specific antigen and an exogenous source of T-cell growth factor are required. The proliferative response of the cloned T cells was found to be virus-specific but it did not distinguish between HSV-1 and HSV-2. Adoptive cell transfer of the cloned T cells helped primed B cells to produce anti-herpes antibodies: the response was antigen-specific and cell dose-dependent. The clone failed to produce a significant DTH reaction in vivo, but did produce high levels of macrophage-activating factor. Furthermore, the T-cell clone could protect from HSV infection, as measured by a reduction in local virus growth, and by enhanced survival following the challenge of mice with a lethal dose of virus. The mechanism(s) whereby this clone protects in vivo is discussed.

  12. Microneedle-mediated immunization of an adenovirus-based malaria vaccine enhances antigen-specific antibody immunity and reduces anti-vector responses compared to the intradermal route

    Science.gov (United States)

    Carey, John B.; Vrdoljak, Anto; O'Mahony, Conor; Hill, Adrian V. S.; Draper, Simon J.; Moore, Anne C.

    2014-01-01

    Substantial effort has been placed in developing efficacious recombinant attenuated adenovirus-based vaccines. However induction of immunity to the vector is a significant obstacle to its repeated use. Here we demonstrate that skin-based delivery of an adenovirus-based malaria vaccine, HAdV5-PyMSP142, to mice using silicon microneedles induces equivalent or enhanced antibody responses to the encoded antigen, however it results in decreased anti-vector responses, compared to intradermal delivery. Microneedle-mediated vaccine priming and resultant induction of low anti-vector antibody titres permitted repeated use of the same adenovirus vaccine vector. This resulted in significantly increased antigen-specific antibody responses in these mice compared to ID-treated mice. Boosting with a heterologous vaccine; MVA-PyMSP142 also resulted in significantly greater antibody responses in mice primed with HAdV5-PyMSP142 using MN compared to the ID route. The highest protection against blood-stage malaria challenge was observed when a heterologous route of immunization (MN/ID) was used. Therefore, microneedle-mediated immunization has potential to both overcome some of the logistic obstacles surrounding needle-and-syringe-based immunization as well as to facilitate the repeated use of the same adenovirus vaccine thereby potentially reducing manufacturing costs of multiple vaccines. This could have important benefits in the clinical ease of use of adenovirus-based immunization strategies. PMID:25142082

  13. 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.

  14. Studies on Purification and Coatation of Polyclonal Antibody for Prolactin Solid Phase Radioimmunoassay in Human Serum

    International Nuclear Information System (INIS)

    El-Bayoumy, A.S.A.; Sallam, Kh.M.; Shafik, H.M.

    2012-01-01

    The objective of the present study was oriented to produce purified polyclonal antibody to prepare a prolactin solid phase coated tubes radioimmunoassay system. In the present study, production of polyclonal antibodies was carried out through immunization of three healthy white male mature New Zealand rabbits with a highly purified sheep prolactin antigen. The obtained anti-sera was purified using an anion exchange reactive group, diethylamino ethyle (DEAE) covalently linked to Sepharose. The purified polyclonal antibody was used for coating polystyrene tubes. The preparation of 125 I-prolactin tracer was carried out using chloramine-T method. The preparation of standards was performed using assay buffer to cover the range from 2 to 200 ng/ml. The optimization and validation tests of the assay were performed to evaluate the validity of the prepared system. In conclusion, this low cost assay would be used in diagnosis of pituitary dysfunction and diagnosis of infertility in males and females

  15. Studies on Purification and Coatation of Polyclonal Antibody for Prolactin Solid Phase Radioimmunoassay in Human Serum

    International Nuclear Information System (INIS)

    El-Bayoumy, A.S.A.; Sallam, Kh.M.; Shafik, H.M.

    2014-01-01

    The objective of the present study was oriented to produce purified polyclonal antibody to prepare a prolactin solid phase coated tubes radioimmunoassay system. In the present study, production of polyclonal antibodies was carried out through immunization of three healthy white male mature New Zealand rabbits with a highly purified sheep prolactin antigen. The obtained anti-sera was purified using an anion exchange reactive group, diethylamino ethyle (DEAE) covalently linked to Sepharose. The purified polyclonal antibody was used for coating polystyrene tubes. The preparation of 125 I-prolactin tracer was carried out using chloramine-T method. The preparation of standards was performed using assay buffer to cover the range from 2 to 200 ng/ml. The optimization and validation tests of the assay were performed to evaluate the validity of the prepared system. In conclusion, this low cost assay would be used in diagnosis of pituitary dysfunction and diagnosis of infertility in males and females.

  16. Use of polyclonal IgG in HIV infection and AIDS

    International Nuclear Information System (INIS)

    Buscombe, J.R.; Oyen, W.J.G.; Corstens, F.H.M.

    1995-01-01

    Nuclear Medicine should have a pivitol role to play in the investigation of patients infected with the Human Immunodeficiency Virus (HIV). Unfortunately the use of scintigraphic techniques to localize infection have not become widely used in Europe. Neither 67 Ga citrate or labelled leukocytes are ideal. In a search for new agents which can be used to identify the presence of infection both 99m Tc and 111 In labelled polyclonal immunoglobulin-C have been investigated. It was found that 99m TC labelled polyclonal immunoglobulin-G was not able to localize infection in either the chest or the abdomen. In contrast 111 In labelled polyclonal immunoglobulin-G had both high sensitivity and specificity for imaging infection in HIV infected patients. If these preliminary results are confirmed immunoglobulin-G could find an important clinical application in this specialized patient group

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

    NARCIS (Netherlands)

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

    2015-01-01

    Particulate antigen delivery systems aimed at the induction of antigen-specific T cells form a promising approach in immunotherapy to replace pharmacokinetically unfavorable soluble antigen formulations. In this study, we developed a delivery system using the model protein antigen ovalbumin (OVA)

  18. Phenotyping polyclonal kappa and lambda light chain molecular mass distributions in patient serum using mass spectrometry.

    Science.gov (United States)

    Barnidge, David R; Dasari, Surendra; Ramirez-Alvarado, Marina; Fontan, Adrian; Willrich, Maria A V; Tschumper, Renee C; Jelinek, Diane F; Snyder, Melissa R; Dispenzieri, Angela; Katzmann, Jerry A; Murray, David L

    2014-11-07

    We previously described a microLC-ESI-Q-TOF MS method for identifying monoclonal immunoglobulins in serum and then tracking them over time using their accurate molecular mass. Here we demonstrate how the same methodology can be used to identify and characterize polyclonal immunoglobulins in serum. We establish that two molecular mass distributions observed by microLC-ESI-Q-TOF MS are from polyclonal kappa and lambda light chains using a combination of theoretical molecular masses from gene sequence data and the analysis of commercially available purified polyclonal IgG kappa and IgG lambda from normal human serum. A linear regression comparison of kappa/lambda ratios for 74 serum samples (25 hypergammaglobulinemia, 24 hypogammaglobulinemia, 25 normal) determined by microflowLC-ESI-Q-TOF MS and immunonephelometry had a slope of 1.37 and a correlation coefficient of 0.639. In addition to providing kappa/lambda ratios, the same microLC-ESI-Q-TOF MS analysis can determine the molecular mass for oligoclonal light chains observed above the polyclonal background in patient samples. In 2 patients with immune disorders and hypergammaglobulinemia, we observed a skewed polyclonal molecular mass distribution which translated into biased kappa/lambda ratios. Mass spectrometry provides a rapid and simple way to combine the polyclonal kappa/lambda light chain abundance ratios with the identification of dominant monoclonal as well as oligoclonal light chain immunoglobulins. We anticipate that this approach to evaluating immunoglobulin light chains will lead to improved understanding of immune deficiencies, autoimmune diseases, and antibody responses.

  19. Expression of deleted, atoxic atypical recombinant beta2 toxin in a baculovirus system and production of polyclonal and monoclonal antibodies.

    Science.gov (United States)

    Serroni, Anna; Magistrali, Chiara Francesca; Pezzotti, Giovanni; Bano, Luca; Pellegrini, Martina; Severi, Giulio; Di Pancrazio, Chiara; Luciani, Mirella; Tittarelli, Manuela; Tofani, Silvia; De Giuseppe, Antonio

    2017-05-25

    Clostridium perfringens is an important animal and human pathogen that can produce more than 16 different major and minor toxins. The beta-2 minor toxin (CPB2), comprising atypical and consensus variants, appears to be involved in both human and animal enterotoxaemia syndrome. The exact role of CPB2 in pathogenesis is poorly investigated, and its mechanism of action at the molecular level is still unknown because of the lack of specific reagents such as monoclonal antibodies against the CPB2 protein and/or the availability of a highly purified antigen. Previous studies have reported that purified wild-type or recombinant CPB2 toxin, expressed in a heterologous system, presented cytotoxic effects on human intestinal cell lines. Undoubtedly, for this reason, to date, these purified proteins have not yet been used for the production of monoclonal antibodies (MAbs). Recently, monoclonal antibodies against CPB2 were generated using peptides designed on predicted antigenic epitopes of this toxin. In this paper we report, for the first time, the expression in a baculovirus system of a deleted recombinant C-terminal 6xHis-tagged atypical CPB2 toxin (rCPB2 Δ1-25 -His 6 ) lacking the 25 amino acids (aa) of the N-terminal putative signal sequence. A high level of purified recombinant rCPB2 Δ1-25 -His 6 was obtained after purification by Ni 2+ affinity chromatography. The purified product showed no in vitro and in vivo toxicity. Polyclonal antibodies and twenty hybridoma-secreting Mabs were generated using purified rCPB2 Δ1-25 -His 6 . Finally, the reactivity and specificity of the new antibodies were tested against both recombinant and wild-type CPB2 toxins. The high-throughput of purified atoxic recombinant CPB2 produced in insect cells, allowed to obtain monoclonal and polyclonal antibodies. The availability of these molecules could contribute to develop immunoenzymatic methods and/or to perform studies about the biological activity of CPB2 toxin.

  20. Enhancement of Human Antigen-Specific Memory T-Cell Responses by Interleukin-7 May Improve Accuracy in Diagnosing Tuberculosis▿ †

    Science.gov (United States)

    Feske, Marsha; Nudelman, Rodolfo J.; Medina, Miguel; Lew, Justin; Singh, Manisha; Couturier, Jacob; Graviss, Edward A.; Lewis, Dorothy E.

    2008-01-01

    Children and immunocompromised adults are at an increased risk of tuberculosis (TB), but diagnosis is more challenging. Recently developed gamma interferon (IFN-γ) release assays provide increased sensitivity and specificity for diagnosis of latent TB, but their use is not FDA approved in immunocompromised or pediatric populations. Both populations have reduced numbers of T cells, which are major producers of IFN-γ. Interleukin 7 (IL-7), a survival cytokine, stabilizes IFN-γ message and increases protein production. IL-7 was added to antigen-stimulated lymphocytes to improve IFN-γ responses as measured by enzyme-linked immunosorbent assay (ELISA) and enzyme-linked immunospot (ELISPOT) assay. Antigens used were tetanus toxoid (n = 10), p24 (from human immunodeficiency virus [HIV], n = 9), and TB peptides (n = 15). Keyhole limpet hemocyanin was used as a negative control, and phytohemagglutinin was the positive control. IL-7 improved antigen-specific responses to all antigens tested including tetanus toxoid, HIV type 1 p24, and TB peptides (ESAT-6 and CFP-10) with up to a 14-fold increase (mean = 3.8), as measured by ELISA. Increased IFN-γ responses from controls, HIV-positive patients, and TB patients were statistically significant, with P values of <0.05, 0.01, and 0.05, respectively. ELISPOT assay results confirmed ELISA findings (P values of <0.01, 0.02, and 0.03, respectively), with a strong correlation between the two tests (R2 = 0.82 to 0.99). Based on average background levels, IL-7 increased detection of IFN-γ by 39% compared to the level with antigen alone. Increased production of IFN-γ induced by IL-7 improves sensitivity of ELISA and ELISPOT assays for all antigens tested. Further enhancement of IFN-γ-based assays might improve TB diagnosis in those populations at highest risk for TB. PMID:18753334

  1. Co-delivery of antigen and IL-12 by Venezuelan equine encephalitis virus replicon particles enhances antigen-specific immune responses and anti-tumor effects

    Science.gov (United States)

    Osada, Takuya; Berglund, Peter; Morse, Michael A.; Hubby, Bolyn; Lewis, Whitney; Niedzwiecki, Donna; Hobeika, Amy; Burnett, Bruce; Devi, Gayathri R.; Clay, Timothy M.; Smith, Jonathan; Lyerly, H. Kim

    2013-01-01

    We recently demonstrated that Venezuelan equine encephalitis (VEE) virus-based replicon particles (VRP) encoding tumor antigens could break tolerance in the immunomodulatory environment of advanced cancer. We hypothesized that local injection of VRP expressing Interleukin-12 (IL-12) at the site of injections of VRP-based cancer vaccines would enhance the tumor-antigen-specific T cell and antibody responses and anti-tumor efficacy. Mice were immunized with VRP encoding the human tumor-associated antigen, carcinoembryonic antigen (CEA) (VRP-CEA(6D)) and VRP-IL-12 was also administered at the same site or at a distant location. CEA-specific T cell and antibody responses were measured. To determine antitumor activity, mice were implanted with MC38-CEA-2 cells and immunized with VRP-CEA with and without VRP-IL-12 and tumor growth and mouse survival were measured. VRP-IL-12 greatly enhanced CEA-specific T cell and antibody responses when combined with VRP-CEA(6D) vaccination. VRP IL-12 was superior to IL-12 protein at enhancing immune responses. Vaccination with VRP-CEA(6D) plus VRP-IL-12 was superior to VRP-CEA(6D) or VRP-IL-12 alone in inducing anti-tumor activity and prolonging survival in tumor-bearing mice. Importantly, local injection of VRP-IL-12 at the VRP-CEA(6D) injection site provided more potent activation of CEA-specific immune responses than VRP-IL-12 injected at a distant site from the VRP-CEA injections. Together, this study shows that VRP-IL-12 enhances vaccination with VRP-CEA(6D) and was more effective at activating CEA-specific T cell responses when locally expressed at the vaccine site. Clinical trials evaluating the adjuvant effect of VRP-IL-12 at enhancing the immunogenicity of cancer vaccines are warranted. PMID:22488274

  2. Arachidonic acid-and docosahexaenoic acid-enriched formulas modulate antigen-specific T cell responses to influenza virus in neonatal piglets.

    Science.gov (United States)

    Bassaganya-Riera, Josep; Guri, Amir J; Noble, Alexis M; Reynolds, Kathryn A; King, Jennifer; Wood, Cynthia M; Ashby, Michael; Rai, Deshanie; Hontecillas, Raquel

    2007-03-01

    Whereas the immunomodulatory effects of feeding either arachidonic acid (AA) or docosahexaenoic acid (DHA) separately have been previously investigated, little is known about the immunomodulatory efficacy of AA or DHA when they are fed in combination as infant formula ingredients. The objective of this study was to investigate the ability of AA- and DHA(AA/DHA)-enriched infant formula to modulate immune responses in the neonate in response to an inactivated influenza virus vaccine. Neonatal piglets (n = 48) were weaned on day 2 of age and distributed into 16 blocks of 3 littermate piglets each. Within each block, piglets were randomly assigned to a control formula, AA/DHA-enriched formula (0.63% AA and 0.34% DHA), or sow milk for 30 d. On day 9, 8 blocks of piglets were immunized with an inactivated influenza virus vaccine. On days 0, 9, 16, 23, and 30 after weaning, we measured influenza virus-specific T cell proliferation and phenotype of T subsets in peripheral blood. A delayed-type hypersensitivity reaction test was administered on day 28. Cytokine messenger RNA expression was determined by quantitative real time reverse transcriptase-polymerase chain reaction on day 30. The influenza virus-specific CD4(+) and CD8(+) T cell ex vivo lymphoproliferative responses were significantly lower on day 23 after immunization in piglets receiving dietary AA/DHA supplementation and sow milk than in those receiving the unsupplemented control formula. The immunomodulatory effects of AA/DHA-enriched formulas were consistent with up-regulation of interleukin 10 in peripheral blood mononuclear cells. Overall, it appears that the AA/DHA-enriched formula modulated antigen-specific T cell responses in part through an interleukin 10-dependent mechanism.

  3. Antigen-Specificity of T Cell Infiltrates in Biopsies With T Cell-Mediated Rejection and BK Polyomavirus Viremia: Analysis by Next Generation Sequencing.

    Science.gov (United States)

    Zeng, G; Huang, Y; Huang, Y; Lyu, Z; Lesniak, D; Randhawa, P

    2016-11-01

    This study interrogates the antigen-specificity of inflammatory infiltrates in renal biopsies with BK polyomavirus (BKPyV) viremia (BKPyVM) with or without allograft nephropathy (BKPyVN). Peripheral blood mononuclear cells (PBMC) from five healthy HLA-A0101 subjects were stimulated by peptides derived from the BKPYV proteome or polymorphic regions of HLA. Next generation sequencing of the T cell-receptor complementary DNA was performed on peptide-stimulated PBMC and 23 biopsies with T cell-mediated rejection (TCMR) or BKPyVN. Biopsies from patients with BKPyVM or BKVPyVN contained 7.7732 times more alloreactive than virus-reactive clones. Biopsies with TCMR also contained BKPyV-specific clones, presumably a manifestation of heterologous immunity. The mean cumulative T cell clonal frequency was 0.1378 for alloreactive clones and 0.0375 for BKPyV-reactive clones. Samples with BKPyVN and TCMR clustered separately in dendrograms of V-family and J-gene utilization patterns. Dendrograms also revealed that V-gene, J-gene, and D-gene usage patterns were a function of HLA type. In conclusion, biopsies with BKPyVN contain abundant allospecific clones that exceed the number of virus-reactive clones. The T cell component of tissue injury in viral nephropathy appears to be mediated primarily by an "innocent bystander" mechanism in which the principal element is secondary T cell influx triggered by both antiviral and anti-HLA immunity. © Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.

  4. Activation of Antigen-Specific CD8(+) T Cells by Poly-DL-Lactide/Glycolide (PLGA) Nanoparticle-Primed Gr-1(high) Cells.

    Science.gov (United States)

    Luo, Wen-Hui; Yang, Ya-Wun

    2016-04-01

    The aim of this study was to investigate the induction of antigen-specific T cell activation and cell cycle modulation by a poly-DL-lactide/glycolide (PLGA) nanoparticle (NP)-primed CD11b(+)Gr-1(high) subset isolated from mouse bone marrow. PLGA NPs containing the ovalbumin (OVA) antigen were prepared using the double emulsion and solvent evaporation method, and protein release rate and cell viability were determined. The Lin2(¯)CD11b(+)Gr-1(high)Ly6c(low) (Gr-1(high)) subset was sorted from the bone marrow of C57BL/6 J mice by fluorescence-activated cell sorting (FACS) and co-cultured with OT-I CD8(+) splenic T cells. Proliferation of OT-I CD8(+) T cells was monitored, and cell cycles were determined by 5-bromo-2'-deoxyuridine (BrdU) labeling. Treatment of Gr-1(high) cells with PLGA/OVA NPs upregulated expression of the SIINFEKL-H2K(b) complex in the context of MHC I. Co-cultures of OT-I CD8(+) T cells with the PLGA/OVA NP-primed Gr-1(high) cells induced the proliferation of T cells in vitro and modulated cell division and morphology. Treatment of Gr-1(high) cells with PLGA/OVA NPs also induced cell apoptosis and necrosis. This study demonstrated the function of PLGA/OVA NPs in the activation of OT-I CD8(+) T cells and the capability of cross-presentation via the Gr-1(high) polymorphonuclear subset from mouse bone marrow.

  5. Targeted Delivery of GP5 Antigen of PRRSV to M Cells Enhances the Antigen-Specific Systemic and Mucosal Immune Responses

    Directory of Open Access Journals (Sweden)

    Luping Du

    2018-01-01

    Full Text Available Efficient delivery of antigens through oral immunization is a first and critical step for successful induction of mucosal immunity, which can provide protection against pathogens invading the mucosa. Membranous/microfold cells (M cells within the mucosa can transcytose internalized antigen without degradation and thus play an important role in initiating antigen-specific mucosal immune responses through inducing secretory IgA production. In this research, we modified poly (D, L-lactide-co-glycolide (PLGA nanoparticles (NPs with Ulex europaeus agglutinin 1 (UEA-1 and successfully prepared an oral vaccine delivery system, UEA-1/PLGA NPs. PLGA NPs were prepared using a standard double emulsion solvent evaporation technique, which can protect the entrapped PRRSV DNA vaccine [pcDNA3.1-SynORF5 (synthetic ORF5] or subunit vaccine ORF5-encoded glycoprotein (GP5 from exposure to the gastrointestinal (GI tract and release the plasmids in a controlled manner. With UEA-1 modification, the UEA-1/PLGA NPs can be effectively transported by M-cells. We investigated immune response induced by UEA-1/PLGA-SynORF5 or UEA-1/PLGA-GP5 following inoculation in mice and piglets. Compared with PLGA-SynORF5 or PLGA-GP5 NPs, UEA-1/PLGA-SynORF5, or UEA-1/PLGA-GP5 NPs stimulated significantly increased serum IgG levels and augmented intestinal IgA levels in mice and piglets (P < 0.05. Our findings indicate UEA-1/PLGA NPs can be applied as a promising and universally robust oral vaccine delivery system.

  6. Targeted Delivery of GP5 Antigen of PRRSV to M Cells Enhances the Antigen-Specific Systemic and Mucosal Immune Responses

    Science.gov (United States)

    Du, Luping; Yu, Zhengyu; Pang, Fengjiao; Xu, Xiangwei; Mao, Aihua; Yuan, Wanzhe; He, Kongwang; Li, Bin

    2018-01-01

    Efficient delivery of antigens through oral immunization is a first and critical step for successful induction of mucosal immunity, which can provide protection against pathogens invading the mucosa. Membranous/microfold cells (M cells) within the mucosa can transcytose internalized antigen without degradation and thus play an important role in initiating antigen-specific mucosal immune responses through inducing secretory IgA production. In this research, we modified poly (D, L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) with Ulex europaeus agglutinin 1 (UEA-1) and successfully prepared an oral vaccine delivery system, UEA-1/PLGA NPs. PLGA NPs were prepared using a standard double emulsion solvent evaporation technique, which can protect the entrapped PRRSV DNA vaccine [pcDNA3.1-SynORF5 (synthetic ORF5)] or subunit vaccine ORF5-encoded glycoprotein (GP5) from exposure to the gastrointestinal (GI) tract and release the plasmids in a controlled manner. With UEA-1 modification, the UEA-1/PLGA NPs can be effectively transported by M-cells. We investigated immune response induced by UEA-1/PLGA-SynORF5 or UEA-1/PLGA-GP5 following inoculation in mice and piglets. Compared with PLGA-SynORF5 or PLGA-GP5 NPs, UEA-1/PLGA-SynORF5, or UEA-1/PLGA-GP5 NPs stimulated significantly increased serum IgG levels and augmented intestinal IgA levels in mice and piglets (P < 0.05). Our findings indicate UEA-1/PLGA NPs can be applied as a promising and universally robust oral vaccine delivery system. PMID:29423381

  7. A fully human IgG1 anti-PD-L1 MAb in an in vitro assay enhances antigen-specific T-cell responses

    OpenAIRE

    Grenga, Italia; Donahue, Renee N; Lepone, Lauren M; Richards, Jacob; Schlom, Jeffrey

    2016-01-01

    Monoclonal antibodies (MAbs) that interfere with checkpoint molecules are being investigated for the treatment of infectious diseases and cancer, with the aim of enhancing the function of an impaired immune system. Avelumab (MSB0010718C) is a fully human IgG1 MAb targeting programmed death-ligand 1 (PD-L1), which differs from other checkpoint-blocking antibodies in its ability to mediate antibody-dependent cell-mediated cytotoxicity. These studies were conducted to define whether avelumab cou...

  8. Antigenic profile of human recombinant PrP: generation and chracterization of a versatile polyclonal antiserum

    NARCIS (Netherlands)

    Sachsamanoglou, M.; Paspaltzis, I.; Petrakis, S.; Verghese-Nikolakaki, S.; Panagiotidis, C.H.; Voitlander, T.; Budka, H.; Langeveld, J.P.M.; Sklaviadis, T.

    2004-01-01

    We describe the quality of a rabbit polyclonal antiserum (Sal1) that was raised against mature human recombinant prion protein (rhuPrP). Epitope mapping demonstrated that the Sal1 antiserum recognized six to eight linear antigenic sites, depending on the animal species. The versatility of the

  9. NYESO-1/LAGE-1s and PRAME are targets for antigen specific T cells in chondrosarcoma following treatment with 5-Aza-2-deoxycitabine.

    Directory of Open Access Journals (Sweden)

    Seth M Pollack

    Full Text Available Chondrosarcoma has no proven systemic option in the metastatic setting. The development of a non-cross-resistant strategy, such as cellular immunotherapy using antigen-specific T cells would be highly desirable. NY-ESO-1 and PRAME are members of the Cancer Testis Antigen (CTA family that have been identified as promising targets for T cell therapy. LAGE-1 is a cancer testis antigen 90% homologous to NY-ESO-1, sharing the 157-165 A*0201 NY-ESO-1 epitope with its transcript variant, LAGE-1s. A number of CTA's have been induced using 5-Aza-2-Deoxycitabine (5-Aza-dC in other cancers. We sought to evaluate the feasibility of targeting chondrosarcoma tumors using NY-ESO-1/LAGE-1s and PRAME specific T cells using 5-Aza-dC to induce antigen expression.We used 11 flash frozen tumors from the University of Washington tumor bank to test for the expression of NY-ESO-1, PRAME, LAGE-1s and LAGE-1L in chondrosarcoma tumors. Using four chondrosarcoma cell lines we tested the expression of these CTA's with and without 5-Aza-dC treatments. Finally, using NY-ESO-1/LAGE-1s and PRAME specific effectors that we generated from sarcoma patients, we evaluated the ability of these T cells to lyse A*0201 expressing chondrosarcoma cell lines in vitro both with and without 5-Aza-dC treatment.A minority (36% of chondrosarcoma tumors expressed either NY-ESO-1 or LAGE-1s at >10% of our reference value and none expressed PRAME at that level. However, in all four of the chondrosarcoma cell lines tested, NY-ESO-1 and PRAME expression could be induced following treatment with 5-Aza-dC including in cell lines where expression was absent or barely detectable. Furthermore, NY-ESO-1/LAGE-1s and PRAME specific CD8+ effector T cells were able to specifically recognize and lyse A*0201 expressing chondrosarcoma cell lines following 5-Aza-dC treatment.These data suggest that adoptive immunotherapy in combination with 5-Aza-dC may be a potential strategy to treat unresectable or metastatic

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

    Directory of Open Access Journals (Sweden)

    Gomez Bianca P

    2012-10-01

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

  11. CD4 Depletion or CD40L Blockade Results in Antigen-Specific Tolerance in a Red Blood Cell Alloimmunization Model

    Directory of Open Access Journals (Sweden)

    Prabitha Natarajan

    2017-08-01

    Full Text Available Approximately 3–10% of human red blood cell (RBC transfusion recipients form alloantibodies to non-self, non-ABO blood group antigens expressed on donor RBCs, with these alloantibodies having the potential to be clinically significant in transfusion and pregnancy settings. However, the majority of transfused individuals never form detectable alloantibodies. Expanding upon observations that children initially transfused with RBCs at a young age are less likely to form alloantibodies throughout their lives, we hypothesized that “non-responders” may not only be ignorant of antigens on RBCs but instead tolerized. We investigated this question in a reductionist murine model, in which transgenic donors express the human glycophorin A (hGPA antigen in an RBC-specific manner. Although wild-type mice treated with poly IC and transfused with hGPA RBCs generated robust anti-hGPA IgG alloantibodies that led to rapid clearance of incompatible RBCs, those transfused in the absence of an adjuvant failed to become alloimmunized. Animals depleted of CD4+ cells or treated with CD40L blockade prior to initial hGPA RBC exposure, in the presence of poly IC, failed to generate detectable anti-hGPA IgG alloantibodies. These non-responders to a primary transfusion remained unable to generate anti-hGPA IgG alloantibodies upon secondary hGPA exposure and did not prematurely clear transfused hGPA RBCs even after their CD4 cells had returned or their CD40L blockade had resolved. This observed tolerance was antigen (hGPA specific, as robust IgG responses to transfused RBCs expressing a third-party antigen occurred in all studied groups. Experiments completed in an RBC alloimmunization model that allowed evaluation of antigen-specific CD4+ T-cells (HOD (hen egg lysozyme, ovalbumin, and human duffyb demonstrated that CD40L blockade prevented the expansion of ovalbumin 323-339 specific T-cells after HOD RBC transfusion and also prevented germinal center formation. Taken

  12. Zinc supplementation induces CD4+CD25+Foxp3+ antigen-specific regulatory T cells and suppresses IFN-γ production by upregulation of Foxp3 and KLF-10 and downregulation of IRF-1.

    Science.gov (United States)

    Maywald, Martina; Rink, Lothar

    2017-08-01

    The essential trace element zinc plays a fundamental role in immune function and regulation since its deficiency is associated with autoimmunity, allergies, and transplant rejection. Thus, we investigated the influence of zinc supplementation on the Th1-driven alloreaction in mixed lymphocyte cultures (MLC), on generation of antigen-specific T cells, and analyzed underlying molecular mechanisms. Cell proliferation and pro-inflammatory cytokine production were monitored by [ 3 H]-thymidine proliferation assay and ELISA, respectively. Analysis of surface and intracellular T cell marker was performed by flow cytometry. Western blotting and mRNA analysis were used for Foxp3, KLF-10, and IRF-1 expression. Zinc supplementation on antigen-specific T cells in physiological doses (50 µM) provokes a significant amelioration of cell proliferation and pro-inflammatory cytokine production after reactivation compared to untreated controls. Zinc administration on MLC results in an increased induction and stabilization of CD4 + CD25 + Foxp3 + and CD4 + CD25 + CTLA-4 + T cells (p zinc-induced upregulation of Foxp3 and KLF-10 and downregulation of IRF-1. However, in resting lymphocytes zinc increases IRF-1. In summary, zinc is capable of ameliorating the allogeneic immune reaction by enhancement of antigen-specific iTreg cells due to modulation of essential molecular targets: Foxp3, KLF-10, and IRF-1. Thus, zinc can be seen as an auspicious tool for inducing tolerance in adverse immune reactions.

  13. Establishment of a panel of in-house polyclonal antibodies for the diagnosis of enterovirus infections.

    Science.gov (United States)

    Kotani, Osamu; Iwata-Yoshikawa, Naoko; Suzuki, Tadaki; Sato, Yuko; Nakajima, Noriko; Koike, Satoshi; Iwasaki, Takuya; Sata, Tetsutaro; Yamashita, Teruo; Minagawa, Hiroko; Taguchi, Fumihiro; Hasegawa, Hideki; Shimizu, Hiroyuki; Nagata, Noriyo

    2015-04-01

    The aim of this study was to establish a reliable method of virus detection for the diagnosis of critical enterovirus infections such as acute infective encephalitis, encephalomyelitis and myocarditis. Because histopathological and immunohistochemical analyses of paraffin-embedded tissues play an important role in recognizing infectious agents in tissue samples, six in-house polyclonal antibodies raised against three representative enteroviruses using an indirect immunofluorescence assay and immunohistochemistry were examined. This panel of polyclonal antibodies recognized three serotypes of enterovirus. Two of the polyclonal antibodies were raised against denatured virus particles from enterovirus A71, one was raised against the recombinant VP1 protein of coxsackievirus B3, and the other for poliovirus type 1 were raised against denatured virus particles, the recombinant VP1 protein and peptide 2C. Western blot analysis revealed that each of these antibodies recognized the corresponding viral antigen and none cross-reacted with non-enteroviruses within the family Picornaviridae. However, all cross-reacted to some extent with the antigens derived from other serotypes of enterovirus. Indirect immunofluorescence assay and immunohistochemistry revealed that the virus capsid and non-structural proteins were localized in the cytoplasm of affected culture cells, and skeletal muscles and neurons in neonatal mice experimentally-infected with human enterovirus. The antibodies also recognized antigens derived from recent clinical isolates of enterovirus A71, coxsackievirus B3 and poliovirus. In addition, immunohistochemistry revealed that representative antibodies tested showed the same recognition pattern according to each serotype. Thus, the panel of in-house anti-enterovirus polyclonal antibodies described herein will be an important tool for the screening and pathological diagnosis for enterovirus infections, and may be useful for the classification of different

  14. Preparation and Purification of Polyclonal Antibodies against Mycobacterium Avium Paratuberculosis Antigens in Rabbit

    Directory of Open Access Journals (Sweden)

    Hafezeh Alizadeh

    2012-12-01

    Full Text Available Background and Objective: Johne’s disease is the chronic granulomatous enteritis of ruminants, and a major health hazard worldwide. In recent years, researchers have focused on mycobacterium avium subsp. paratuberculosis (MAP antigens in diagnostic tests. Identification of antibodies against MAP antigens is, therefore, effective for the diagnosis or preparation of vaccine. The aim of this study was to prepare and purify polyclonal antibodies against MAP antigens. Materials and Methods: A New Zealand white rabbit was immunized at a certain time period with MAP antigens and Freund’s adjuvant. After the immunization of the animal, the rabbit was bled to obtain enriched serum. Immunoglobulins were obtained via sedimentation with ammonium sulfate 35% and then IgG was purified by ion exchange (DEAE-cellulose chromatography. Serologic test was used to evaluate the interaction of antigens and antibodies. Results: Ion exchange chromatography of IgG showed one peak, and SDS_PAGE of IgG showed a single band. Serologic test was applied and clear precipitation lines were appeared up to 1:16 dilution, which indicated the high quality of the product. Conclusion: In this study, the humoral immune response was induced well by immunization with MAP antigens in a New Zealand white rabbit and polyclonal antibodies were produced in high titers. Polyclonal antibodies are relatively inexpensive and easy to produce in large quantities and can connect to the more connective sites, resulting in better sensitivity. Identification of polyclonal antibodies via immunological tests can play a significant role in studying MAP disorders.

  15. Large-scale in vitro expansion of polyclonal human switched-memory B lymphocytes.

    Directory of Open Access Journals (Sweden)

    Sonia Néron

    Full Text Available Polyclonal preparations of therapeutic immunoglobulins, namely intravenous immunoglobulins (IVIg, are essential in the treatment of immunodeficiency and are increasingly used for the treatment of autoimmune and inflammatory diseases. Currently, patients' accessibility to IVIg depends exclusively upon volunteer blood donations followed by the fractionation of pooled human plasma obtained from thousands of individuals. Presently, there are no in vitro cell culture procedures allowing the preparation of polyclonal human antibodies. All in vitro human therapeutic antibodies that are currently generated are based on monoclonal antibodies, which are mostly issued from genetic engineering or single cell antibody technologies. Here, we describe an in vitro cell culture system, using CD40-CD154 interactions, that leads to a 1×10(6-fold expansion of switched memory B lymphocytes in approximately 50 days. These expanded cells secrete polyclonal IgG, which distribution into IgG(1, IgG(2, IgG(3 and IgG(4 is similar to that of normal human serum. Such in vitro generated IgG showed relatively low self-reactivity since they interacted moderately with only 24 human antigens among a total of 9484 targets. Furthermore, up to one liter of IgG secreting cells can be produced in about 40 days. This experimental model, providing large-scale expansion of human B lymphocytes, represents a critical step toward the in vitro production of polyclonal human IgG and a new method for the ex vivo expansion of B cells for therapeutic purposes.

  16. Estimation of polyclonal IgG4 hybrids in normal human serum.

    Science.gov (United States)

    Young, Elizabeth; Lock, Emma; Ward, Douglas G; Cook, Alexander; Harding, Stephen; Wallis, Gregg L F

    2014-07-01

    The in vivo or in vitro formation of IgG4 hybrid molecules, wherein the immunoglobulins have exchanged half molecules, has previously been reported under experimental conditions. Here we estimate the incidence of polyclonal IgG4 hybrids in normal human serum and comment on the existence of IgG4 molecules with different immunoglobulin light chains. Polyclonal IgG4 was purified from pooled or individual donor human sera and sequentially fractionated using light-chain affinity and size exclusion chromatography. Fractions were analysed by SDS-PAGE, immunoblotting, ELISA, immunodiffusion and matrix-assisted laser-desorption mass spectrometry. Polyclonal IgG4 purified from normal serum contained IgG4κ, IgG4λ and IgG4κ/λ molecules. Size exclusion chromatography showed that IgG4 was principally present in monomeric form (150 000 MW). SDS-PAGE, immunoblotting and ELISA showed the purity of the three IgG4 samples. Immunodiffusion, light-chain sandwich ELISA and mass spectrometry demonstrated that both κ and λ light chains were present on only the IgG4κ/λ molecules. The amounts of IgG4κ/λ hybrid molecules ranged from 21 to 33% from the five sera analysed. Based on the molecular weight these molecules were formed of two IgG4 heavy chains plus one κ and one λ light chain. Polyclonal IgG (IgG4-depleted) was similarly fractionated according to light-chain specificity. No evidence of hybrid IgG κ/λ antibodies was observed. These results indicate that hybrid IgG4κ/λ antibodies compose a substantial portion of IgG4 from normal human serum. © 2014 John Wiley & Sons Ltd.

  17. Identification of swine influenza virus epitopes and analysis of multiple specificities expressed by cytotoxic T cell subsets

    DEFF Research Database (Denmark)

    Pedersen, Lasse Eggers; Breum, Solvej Østergaard; Riber, Ulla

    2014-01-01

    Background: Major histocompatibility complex (MHC) class I peptide binding and presentation are essential for antigen-specific activation of cytotoxic T lymphocytes (CTLs) and swine MHC class I molecules, also termed swine leukocyte antigens (SLA), thus play a crucial role in the process that leads...... to elimination of viruses such as swine influenza virus (SwIV). This study describes the identification of SLA-presented peptide epitopes that are targets for a swine CTL response, and further analyses multiple specificities expressed by SwIV activated CTL subsets. Findings: Four SwIV derived peptides were...

  18. Generation and Characterization of Polyclonal Antibody Against Part of Immunoglobulin Constant Heavy υ Chain of Goose

    Science.gov (United States)

    Zhao, Panpan; Guo, Yongli; Ma, Bo; Wang, Junwei

    2014-01-01

    Immunoglobulin Y (abbreviated as IgY) is a type of immunoglobulin that is the major antibody in bird, reptile, and lungfish blood. IgY consists of two light (λ) and two heavy (υ) chains. In the present study, polyclonal antibody against IgYFc was generated and evaluated. rIgYCυ3/Cυ4 was expressed in Escherichia coli, purified and utilized to raise polyclonal antibody in rabbit. High affinity antisera were obtained, which successfully detected the antigen at a dilution of 1:204,800 for ELISA assay. The antibody can specifically recognize both rIgYCυ3/Cυ4 and native IgY by Western bolt analysis. Furthermore, the serum of Grus japonensis or immunoglobulin of chicken, duck, turkey, and silkie samples and dynamic changes of serum GoIgY after immunogenicity with GPV-VP3-virus-like particles (GPV-VP3-VLPs) can be detected with the anti-GoIgYFc polyclonal antibody. These results suggested that the antibody is valuable for the investigation of biochemical properties and biological functions of GoIgY. PMID:25171010

  19. Iodine-131 labeled anti-CEA polyclonal antibody detection of gastrointestinal cancer

    International Nuclear Information System (INIS)

    Nabi, H.A.; Hinkle, G.H.; Olsen, J.O.; Haagensen, D.A.; Thurston, M.O.; Mojzisik, C.; Houchens, D.; Martin, E.W. Jr.

    1984-01-01

    To localize gastrointestinal tumor, 31 patients were injected with 1.7-2.1 mCi I-131 anti-CEA baboon polyclonal antibody. Whole body imaging at 48, 72, and occasionally 96 hrs was performed with a Signa Camera (Technicare) peaked at 364 keV with 20% window. Additional spot views were usually obtained. No subtraction methods were used. All patients had surgical and pathological confirmation of the nuclear medicine studies. Labeled antibody images were positive in 15 (8 recurrent or metastatic colorectal, 2 gastric, 1 pancreatic, 1 primary colon, and 1 breast metastatic to chest wall). In 1, antibody images were positive for metastatic deposits in para-aortic lymph nodes, but negative for primary rectal tumor. True negative images were observed in 6; false negative images in 9 (4 liver metastases, 2 rectal, 1 pancreatic, 1 mesenteric lymph node metastasis, 1 bone metastasis). In all cases, no correlation existed between preoperative CEA serum levels and imaging. I-131 labeled anti-CEA polyclonal antibody imaging proved highly efficient in detecting gastric cancer (2/2) and moderately efficient in detecting recurrent colorectal cancer (8/15). On the other hand, the I-131 labeled polyclonal anti-CEA antibody imaging was of limited value in detecting colon cancer (1/9), pancreatic cancer (1/4) and metastatic liver disease

  20. A Time- and Cost-Saving Method of Producing Rat Polyclonal Antibodies

    International Nuclear Information System (INIS)

    Wakayama, Tomohiko; Kato, Yukio; Utsumi, Rie; Tsuji, Akira; Iseki, Shoichi

    2006-01-01

    Producing antibodies usually takes more than three months. In the present study, we introduce a faster way of producing polyclonal antibodies based on preparation of the recombinant oligopeptide as antigen followed by immunization of rats. Using this method, we produced antisera against two mouse proteins: ERGIC-53 and c-Kit. An expression vector ligated with a pair of complementary synthetic oligodeoxyribonucleotides encoding the protein was introduced into bacteria, and the recombinant oligopeptide fused with the carrier protein glutathione-S-transferase was purified. Wistar rats were immunized by injecting the emulsified antigen subcutaneously into the hind footpads, followed by a booster injection after 2 weeks. One week after the booster, the sera were collected and examined for the antibody titer by immunohistochemistry. Antisera with 1600-fold titer at the maximum were obtained for both antigens and confirmed for their specificity by Western blotting. Anti-ERGIC-53 antisera recognized acinar cells in the sublingual gland, and anti-c-Kit antisera recognized spermatogenic and Leydig cells in the testis. These antisera were applicable to fluorescent double immunostaining with mouse monoclonal or rabbit polyclonal antibodies. Consequently, this method enabled us to produce specific rat polyclonal antisera available for immunohistochemistry in less than one month at a relatively low cost

  1. Comparison of monoclonal and polyclonal ELISAs for fecal elastase in patients with cystic fibrosis and pancreatic insufficiency.

    Science.gov (United States)

    Borowitz, Drucy; Lin, Rong; Baker, Susan S

    2007-02-01

    Two enzyme-linked immunosorbent assay methodologies are used to detect pancreatic insufficiency: monoclonal and polyclonal. We sought to compare these assays in patients with cystic fibrosis and to correlate these with the coefficient of fat absorption (CFA). As part of a larger study, subjects had stool elastase measured by both methods while taking exogenous enzymes. Subjects subsequently stopped enzymes and had a fecal fat balance study performed; the CFA was then calculated. One hundred twenty-four subjects participated in this substudy. The median values for the monoclonal and polyclonal assays were 0.3 and 22.75 microg/g, respectively. The correlation coefficient between the 2 tests was 0.86 (P definition of pancreatic insufficiency was set at a CFA definition of pancreatic insufficiency was set at <100 microg/g, then the monoclonal and polyclonal assay positive predictive values were 97.6% (120 of 123) and 97.4% (111 of 114), respectively. The positive predictive value of both monoclonal and polyclonal fecal elastase in patients with cystic fibrosis is extremely good; however, correlation of either test with CFA was poor. The median value for the polyclonal elastase assay is higher than for the monoclonal assay, which could potentially lead to lower sensitivity of the polyclonal assay at lower cutpoints for the monoclonal assay is used.

  2. Leukocyte function-associated antigen-1-dependent lysis of Fas+ (CD95+/Apo-1+) innocent bystanders by antigen-specific CD8+ CTL.

    Science.gov (United States)

    Kojima, H; Eshima, K; Takayama, H; Sitkovsky, M V

    1997-09-15

    Exquisite specificity toward Ag-bearing cells (cognate targets) is one of the most important properties of CD8+ CTL-mediated cytotoxicity. Using highly Ag-specific CD8+ CTL lines and clones, which spare noncognate, Ag-free targets, we found that in the presence of Ag-bearing targets the CTL acquire the ability to lyse noncognate target cells (bystanders). It is shown that the unexpectedly rapid and efficient lysis of bystanders by Ag-activated CTL is mediated by a Fas ligand (FasL)/Fas-based mechanism and does not depend on perforin. The CTL lysed Fas-expressing bystanders, but spared the Fas-negative or anti-Fas mAb-resistant bystander cells. Accordingly, the FasL-deficient gld/gld CTL did not kill bystanders, while perforin-deficient CTL did. Unlike anti-Fas mAb-induced cell death, the lysis of bystanders was not only FasL/Fas dependent but also required adhesion molecule LFA-1 on the surface of the activated CTL. Lysis of bystanders is viewed as acceptable "collateral" damage, but the persistent presence of activated CTL could result in immunopathologies involving functional Fas-expressing tissues.

  3. Role of 4-1BB receptor in the control played by CD8(+ T cells on IFN-gamma production by Mycobacterium tuberculosis antigen-specific CD4(+ T Cells.

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    Carla Palma

    Full Text Available BACKGROUND: Antigen-specific IFN-gamma producing CD4(+ T cells are the main mediators of protection against Mycobacterium tuberculosis infection both under natural conditions and following vaccination. However these cells are responsible for lung damage and poor vaccine efficacy when not tightly controlled. Discovering new tools to control nonprotective antigen-specific IFN-gamma production without affecting protective IFN-gamma is a challenge in tuberculosis research. METHODS AND FINDINGS: Immunization with DNA encoding Ag85B, a candidate vaccine antigen of Mycobacterium tuberculosis, elicited in mice a low but protective CD4(+ T cell-mediated IFN-gamma response, while in mice primed with DNA and boosted with Ag85B protein a massive increase in IFN-gamma response was associated with loss of protection. Both protective and non-protective Ag85B-immunization generated antigen-specific CD8(+ T cells which suppressed IFN-gamma-secreting CD4(+ T cells. However, ex vivo ligation of 4-1BB, a member of TNF-receptor super-family, reduced the massive, non-protective IFN-gamma responses by CD4(+ T cells in protein-boosted mice without affecting the low protective IFN-gamma-secretion in mice immunized with DNA. This selective inhibition was due to the induction of 4-1BB exclusively on CD8(+ T cells of DNA-primed and protein-boosted mice following Ag85B protein stimulation. The 4-1BB-mediated IFN-gamma inhibition did not require soluble IL-10, TGF-beta, XCL-1 and MIP-1beta. In vivo Ag85B stimulation induced 4-1BB expression on CD8(+ T cells and in vivo 4-1BB ligation reduced the activation, IFN-gamma production and expansion of Ag85B-specific CD4(+ T cells of DNA-primed and protein-boosted mice. CONCLUSION/SIGNIFICANCE: Antigen-specific suppressor CD8(+ T cells are elicited through immunization with the mycobacterial antigen Ag85B. Ligation of 4-1BB receptor further enhanced their suppressive activity on IFN-gamma-secreting CD4(+ T cells. The selective

  4. Cytotoxicity of fluorographene

    Czech Academy of Sciences Publication Activity Database

    Teo, W. Z.; Sofer, Z.; Šembera, Filip; Janoušek, Zbyněk; Pumera, M.

    2015-01-01

    Roč. 5, č. 129 (2015), s. 107158-107165 ISSN 2046-2069 R&D Projects: GA ČR(CZ) GA15-09001S Institutional support: RVO:61388963 Keywords : fluorinated graphene * viability assays * cytotoxicity Subject RIV: CC - Organic Chemistry Impact factor: 3.289, year: 2015

  5. Comprehensive Analysis of Cytomegalovirus pp65 Antigen-Specific CD8+ T Cell Responses According to Human Leukocyte Antigen Class I Allotypes and Intraindividual Dominance

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    Seung-Joo Hyun

    2017-11-01

    Full Text Available To define whether individual human leukocyte antigen (HLA class I allotypes are used preferentially in human cytomegalovirus (CMV-specific cytotoxic T lymphocyte responses, CD8+ T cell responses restricted by up to six HLA class I allotypes in an individual were measured in parallel using K562-based artificial antigen-presenting cells expressing both CMV pp65 antigen and one of 32 HLA class I allotypes (7 HLA-A, 14 HLA-B, and 11 HLA-C present in 50 healthy Korean donors. The CD8+ T cell responses to pp65 in the HLA-C allotypes were lower than responses to those in HLA-A and -B allotypes and there was no difference between the HLA-A and HLA-B loci. HLA-A*02:01, -B*07:02, and -C*08:01 showed the highest magnitude and frequency of immune responses to pp65 at each HLA class I locus. However, HLA-A*02:07, -B*59:01, -B*58:01, -B*15:11, -C*03:02, and -C*02:02 did not show any immune responses. Although each individual has up to six different HLA allotypes, 46% of the donors showed one allotype, 24% showed two allotypes, and 2% showed three allotypes that responded to pp65. Interestingly, the frequencies of HLA-A alleles were significantly correlated with the positivity of specific allotypes. Our results demonstrate that specific HLA class I allotypes are preferentially used in the CD8+ T cell immune response to pp65 and that a hierarchy among HLA class I allotypes is present in an individual.

  6. Deposition of idiotype-anti-idiotype immune complexes in renal glomeruli after polyclonal B cell activation

    International Nuclear Information System (INIS)

    Goldman, M.; Rose, L.M.; Hochmann, A.; Lambert, P.H.

    1982-01-01

    We investigated the possible role of idiotypic interactions in the pathogenesis of the glomerular lesions observed in mice undergoing polyclonal B cell activation. BALB/c mice were studied for the presence of renal deposits of T15 idiotype-anti-T15 idiotype-immune complexes (IC) after injection of bacterial lipopolysaccharides (LPS). The T15 idiotype is the major idiotype of BALB/c mice anti-phosphorylcholine (PC) antibodies, which are cross-reactive with the idiotype of the TEPC-15 myeloma protein. This model was used because T15 idiotype-anti-T15 idiotype IC have been detected in the circulation of BALB/c mice after polyclonal B cell activation. First, an idiotype-specific immunofluorescence technique allowed us to detect T15 idiotype-bearing immunoglobulins in glomeruli from day 6 to day 28 after LPS injection. Second, fluorescein isothiocyanate-conjugated TEPC-15 myeloma protein was found to localize in the glomeruli after in vivo injection 18 d after LPS administration. This renal localization was shown to be idiotype-specific and could be quantified in a trace-labeling experiment. Third, kidney-deposited immunoglobulins of mice injected with LPS were eluted, radiolabeled, and analyzed by radioimmunoassay. Both T15 idiotype-bearing immunoglobulins and anti-T15 idiotype antibodies were detected in the eluates, providing further evidence for a renal deposition of T15 idiotype-anti-T15 idiotype IC. Polyclonal B cell activation is likely to result in a simultaneous triggering of many idiotypic clones and of corresponding anti-idiotypic clones represented in the B cell repertoire. This could lead to the formation of a variety of idiotype-anti-idiotype IC that could participate in the development of glomerular lesions

  7. KIT of human polyclonal IGG for the I diagnostic of infectious processes

    International Nuclear Information System (INIS)

    Perera, Alejandro

    1997-01-01

    Early diagnosis of infections can be performed by using non-invasive techniques of Nuclear Medicine, even before appearing anatomical damage of the tissues. The main aim of the present work was to obtain a freeze-dried kit for direct labelling of human polyclonal IgG, for the detection of septic processes by scintigraphy. 99mT c-IgG labelling procedure was carried out by Schwarz method Its was obtained the best yields of 99m Tc using using sodium pyrophosphate decahydrate as a week chelating agent

  8. Technetium-99m labeling anti-amastigote polyclonal antibodies of Leishmania amazonensis

    International Nuclear Information System (INIS)

    Araujo, J.G.V.C.; Toledo, V.P.C.P.; Guimaraes, T.M.P.D.; Bernardo-Filho, M.; Simal, C.J.R.; Mota, L.G.; Diniz, S.O.F.; Cardoso, V.N.

    2002-01-01

    Anti-amastigote polyclonal antibody (IgG) was incubated with solutions of stannous chloride and sodium borohidride. After that, 3.7 MBq of technetium-99m ( 99m Tc) was added. A labeling yield of the antibody about 84% was obtained. After filtration of 99m Tc-IgG, the radiochemical purity increased from 84 to 95%. The labeling of IgG with 99m Tc did not modify the immunoreactivity of the antibody, since it was able to identify in vitro and in vivo the specific antigen of Leishmania amazonensis

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

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    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.

  10. Altered Memory T-Cell Responses to Bacillus Calmette-Guerin and Tetanus Toxoid Vaccination and Altered Cytokine Responses to Polyclonal Stimulation in HIV-Exposed Uninfected Kenyan Infants.

    Science.gov (United States)

    Garcia-Knight, Miguel A; Nduati, Eunice; Hassan, Amin S; Gambo, Faith; Odera, Dennis; Etyang, Timothy J; Hajj, Nassim J; Berkley, James Alexander; Urban, Britta C; Rowland-Jones, Sarah L

    2015-01-01

    Implementation of successful prevention of mother-to-child transmission of HIV strategies has resulted in an increased population of HIV-exposed uninfected (HEU) infants. HEU infants have higher rates of morbidity and mortality than HIV-unexposed (HU) infants. Numerous factors may contribute to poor health in HEU infants including immunological alterations. The present study assessed T-cell phenotype and function in HEU infants with a focus on memory Th1 responses to vaccination. We compared cross-sectionally selected parameters at 3 and 12 months of age in HIV-exposed (n = 42) and HU (n = 28) Kenyan infants. We measured ex vivo activated and bulk memory CD4 and CD8 T-cells and regulatory T-cells by flow cytometry. In addition, we measured the magnitude, quality and memory phenotype of antigen-specific T-cell responses to Bacillus Calmette-Guerin and Tetanus Toxoid vaccine antigens, and the magnitude and quality of the T cell response following polyclonal stimulation with staphylococcal enterotoxin B. Finally, the influence of maternal disease markers on the immunological parameters measured was assessed in HEU infants. Few perturbations were detected in ex vivo T-cell subsets, though amongst HEU infants maternal HIV viral load positively correlated with CD8 T cell immune activation at 12 months. Conversely, we observed age-dependent differences in the magnitude and polyfunctionality of IL-2 and TNF-α responses to vaccine antigens particularly in Th1 cells. These changes mirrored those seen following polyclonal stimulation, where at 3 months, cytokine responses were higher in HEU infants compared to HU infants, and at 12 months, HEU infant cytokine responses were consistently lower than those seen in HU infants. Finally, reduced effector memory Th1 responses to vaccine antigens were observed in HEU infants at 3 and 12 months and higher central memory Th1 responses to M. tuberculosis antigens were observed at 3 months only. Long-term monitoring of vaccine efficacy

  11. Altered Memory T-Cell Responses to Bacillus Calmette-Guerin and Tetanus Toxoid Vaccination and Altered Cytokine Responses to Polyclonal Stimulation in HIV-Exposed Uninfected Kenyan Infants.

    Directory of Open Access Journals (Sweden)

    Miguel A Garcia-Knight

    Full Text Available Implementation of successful prevention of mother-to-child transmission of HIV strategies has resulted in an increased population of HIV-exposed uninfected (HEU infants. HEU infants have higher rates of morbidity and mortality than HIV-unexposed (HU infants. Numerous factors may contribute to poor health in HEU infants including immunological alterations. The present study assessed T-cell phenotype and function in HEU infants with a focus on memory Th1 responses to vaccination. We compared cross-sectionally selected parameters at 3 and 12 months of age in HIV-exposed (n = 42 and HU (n = 28 Kenyan infants. We measured ex vivo activated and bulk memory CD4 and CD8 T-cells and regulatory T-cells by flow cytometry. In addition, we measured the magnitude, quality and memory phenotype of antigen-specific T-cell responses to Bacillus Calmette-Guerin and Tetanus Toxoid vaccine antigens, and the magnitude and quality of the T cell response following polyclonal stimulation with staphylococcal enterotoxin B. Finally, the influence of maternal disease markers on the immunological parameters measured was assessed in HEU infants. Few perturbations were detected in ex vivo T-cell subsets, though amongst HEU infants maternal HIV viral load positively correlated with CD8 T cell immune activation at 12 months. Conversely, we observed age-dependent differences in the magnitude and polyfunctionality of IL-2 and TNF-α responses to vaccine antigens particularly in Th1 cells. These changes mirrored those seen following polyclonal stimulation, where at 3 months, cytokine responses were higher in HEU infants compared to HU infants, and at 12 months, HEU infant cytokine responses were consistently lower than those seen in HU infants. Finally, reduced effector memory Th1 responses to vaccine antigens were observed in HEU infants at 3 and 12 months and higher central memory Th1 responses to M. tuberculosis antigens were observed at 3 months only. Long-term monitoring of

  12. 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.

  13. Anti-IL-39 (IL-23p19/Ebi3) polyclonal antibodies ameliorate autoimmune symptoms in lupus-like mice

    Science.gov (United States)

    Wang, Xiaoqian; Zhang, Yu; Wang, Zhiding; Liu, Xiaoling; Zhu, Gaizhi; Han, Gencheng; Chen, Guojiang; Hou, Chunmei; Wang, Tianxiao; Shen, Beifen; Li, Yan; Xiao, He; Ma, Ning; Wang, Renxi

    2018-01-01

    The interleukin (IL)-12 family cytokines have been examined as therapeutic targets in the treatment of several autoimmune diseases. Our previous study showed that a novel IL-12 family cytokine, IL-39 (IL-23p19/Ebi3) mediates inflammation in lupus-like mice. In the present study, the effect of anti-mouse IL-39 polyclonal antibodies on autoimmune symptoms in lupus-like mice was investigated. Rabbit anti-mouse IL-39 polyclonal antibodies were produced by immunization with recombinant mouse IL-39, and purified using protein A chromatography. These antibodies were subsequently used to treat lupus-like mice. Flow cytometry, captured images, ELISA and H&E staining were used to determine the effect of anti-IL-39 polyclonal antibodies on inflammatory cells, autoantibody titers, proteinuria, infiltrating inflammatory cells and the structure of the glomerular region. The anti-IL-39 polyclonal antibodies effectively reduced the numbers of inflammatory cells, splenomegaly, autoantibody titers, proteinuria, infiltrating inflammatory cells, and restored the structure of the glomerular region in MRL/lpr mice. Taken together, these results suggested that anti-IL-39 polyclonal antibodies ameliorated autoimmune symptoms in lupus-like mice. Therefore, IL-39 may be used as a possible target for the treatment of systemic lupus erythematosus. PMID:29138852

  14. Determination of Aspergillus pathogens in agricultural products by a specific nanobody-polyclonal antibody sandwich ELISA.

    Science.gov (United States)

    Wang, Ting; Li, Peiwu; Zhang, Qi; Zhang, Wen; Zhang, Zhaowei; Wang, Tong; He, Ting

    2017-06-28

    Aspergillus and its poisonous mycotoxins are distributed worldwide throughout the environment and are of particular interest in agriculture and food safety. In order to develop a specific method for rapid detection of Aspergillus flavus to forecast diseases and control aflatoxins, a nanobody, PO8-VHH, highly reactive to A. flavus was isolated from an immunized alpaca nanobody library by phage display. The nanobody was verified to bind to the components of extracellular and intracellular antigen from both A. flavus and A. parasiticus. To construct a sandwich format immunoassay, polyclonal antibodies against Aspergillus were raised with rabbits. Finally, a highly selective nanobody-polyclonal antibody sandwich enzyme-linked immunosorbent assay was optimized and developed. The results revealed that the detection limits of the two fungi were as low as 1 μg mL -1 , and that it is able to detect fungal concentrations below to 2 μg mg -1 of peanut and maize grains in both artificially and naturally contaminated samples. Therefore, we here provided a rapid and simple method for monitoring Aspergillus spp. contamination in agricultural products.

  15. Production of Polyclonal Antibody against Grapevine fanleaf virus Movement Protein Expressed in Escherichia coli

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    Davoud Koolivand

    2016-10-01

    Full Text Available The genomic region of Grapevine fanleaf virus (GFLV encoding the movement protein (MP was cloned into pET21a and transformed into Escherichia coli strain BL21 (DE3 to express the protein. Induction was made with a wide range of isopropyl-β-D-thiogalactopyranoside (IPTG concentrations (1, 1.5, and 2 mM each for duration of 4, 6, or 16 h. However, the highest expression level was achieved with 1 mM IPTG for 4 h. Identity of the expressed protein was confirmed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE followed by Western blotting. The expressed 41 kDa protein was purified under denaturing condition by affinity chromatography, reconfirmed by Western blotting and plate-trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA before being used as a recombinant antigen to raise polyclonal antibodies in rabbits. Purified anti-GFLV MP immunoglobulines (IgGs and conjugated IgGs detected the expressed MP and GFLV virions in infected grapevines when used in PTA-ELISA, double antibody sandwich-ELISA, and Western blotting. This is the first report on the production of anti-GFLV MP polyclonal antibodies and application for the virus detection.

  16. Development, characterization, and use of monoclonal and polyclonal antibodies against the myxosporean, Ceratomyxa shasta

    Science.gov (United States)

    Bartholomew, J.L.; Rohovec, J.S.; Fryer, J.L.

    1989-01-01

    Both monoclonal and polyclonal antisera were produced against Ceratomyxa shasta. Ascites containing trophozoites of the parasite was collected from infected fish and used as antigen for immunization of mice. The resulting monoclonal antibodies reacted specifically with trophozoite and sporoblast stages but did not react with C. shasta spores by either indirect fluorescent antibody techniques or in Western blots. This indicates that some C. shasta antigens are specific to certain life stages of the parasite. Polyclonal antiserum was produced in a rabbit by injecting a spore protein electro-eluted from an SDS-polyacrylamide gel. This antiserum reacted with both trophozoites and spores by indirect fluorescent antibody techniques and in Western blots. All antisera were tested for cross-reactivity to trout white blood cells, a contaminant of the ascites, and to other myxosporea. Two monoclonal antibodies reacted with white blood cells and myxosporea of the genera Sphaerospora and Myxobilatus. One hybridoma produced antibodies of high specificity for C. shasta pre-spore stages. This is the first report of a monoclonal antibody produced against a myxosporean parasite.

  17. Induction of polyclonal B cell activation and differentiation by the AIDS retrovirus (HTLV-III/LAV)

    International Nuclear Information System (INIS)

    Higgins, S.E.; Schnittman, S.M.; Lane, H.C.; Folks, T.; Koenig, S.; Fauci, A.S.

    1986-01-01

    The immune systems of individuals infected with HTLV-III/LAV are characterized by a profound defect in cellular immunity together with paradoxical polyclonal B cell activation. The present study examined the direct effects of HTLV-III/LAV on B lymphocytes. Peripheral blood B cells from healthy donors were incubated with a variety of HTLV-III/LAV isolates for 1 h and 3 H-thymidine incorporation was measured at multiple time points. Responses ranged from 9000-28,000 cpm and peaked on day 4. This B cell activation was not enhanced by the addition of interleukin-2 to culture, was not synergistic with Staphylococcus aureus Cowan I, was not modulated by the addition of T lymphocytes to culture, and was not associated with B cell transformation. Supernatant Ig could first be detected in virus-activated cultures at day 4, plateaued by day 8, and yielded a mean of 12,500 ng IgG+IgM/ml/50,000 B cells. Thus, HTLV-III/LAV is a potent T cell independent B cell mitogen capable of inducing B cell activation, proliferation, and differentiation comparable in magnitude to that of the most potent B cell activators. This biological property of HTLV-III/LAV may help explain the profound polyclonal B cell activation observed in patients with AIDS and may provide investigators with another probe for investigating the mechanisms of B cell activation

  18. A novel method for producing target cells and assessing cytotoxic T lymphocyte activity in outbred hosts

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    Bendinelli Mauro

    2009-03-01

    Full Text Available Abstract Background Cytotoxic T lymphocytes play a crucial role in the immunological control of microbial infections and in the design of vaccines and immunotherapies. Measurement of cytotoxic T lymphocyte activity requires that the test antigen is presented by target cells having the same or compatible class I major hystocompatibility complex antigens as the effector cells. Conventional assays use target cells labeled with 51chromium and infer cytotoxic T lymphocyte activity by measuring the isotope released by the target cells lysed following incubation with antigen-specific cytotoxic T lymphocytes. This assay is sensitive but needs manipulation and disposal of hazardous radioactive reagents and provides a bulk estimate of the reporter released, which may be influenced by spontaneous release of the label and other poorly controllable variables. Here we describe a novel method for producing target in outbred hosts and assessing cytotoxic T lymphocyte activity by flow cytometry. Results The method consists of culturing skin fibroblasts, immortalizing them with a replication defective clone of simian virus 40, and finally transducing them with a bicistronic vector encoding the target antigen and the reporter green fluorescent protein. When used in a flow cytometry-based assay, the target cells obtained with this method proved valuable for assessing the viral envelope protein specific cytotoxic T lymphocyte activity in domestic cats acutely or chronically infected with feline immunodeficiency virus, a lentivirus similar to human immunodeficiency virus and used as animal model for AIDS studies. Conclusion Given the versatility of the bicistronic vector used, its ability to deliver multiple and large transgenes in target cells, and its extremely wide cell specificity when pseudotyped with the vesicular stomatitis virus envelope protein, the method is potentially exploitable in many animal species.

  19. THE USE OF THE SPECIFIC ANTI-SALMONELLA POLYCLONAL ANTIBODIES ISOLATED FROM HEN EGGS, IN SALMONELLOSIS PROPHYLAXIS

    Directory of Open Access Journals (Sweden)

    CRISTE ADRIANA

    2007-01-01

    Full Text Available The administration of increased doses of antibodies in groupsexperimentally infected with Salmonella gallinarum, in order torecord the efficiency of their administration in salmonellosisprophylaxis was the aim of our research. When a low infectiondose, 1x107 CFU Salmonella gallinarum, was used theadministration of IgY polyclonal antibodies as immunoglobulinextract, or even yolk administration had a protective effect againstgerms invasion. This effect was not recorded when a 10 folds higherdose was administered (1x108 CFU. The prophylactic effect of theadministration of polyclonal antibodies is demonstrated.

  20. THE USE OF THE SPECIFIC ANTI-SALMONELLA POLYCLONAL ANTIBODIES ISOLATED FROM HEN EGGS, IN SALMONELLOSIS PROPHYLAXIS

    Directory of Open Access Journals (Sweden)

    ADRIANA CRISTE

    2007-05-01

    Full Text Available The administration of increased doses of antibodies in groups experimentallyinfected with Salmonella gallinarum, in order to record the efficiency of theiradministration in salmonellosis prophylaxis was the aim of our research. When alow infection dose, 1x107 CFU Salmonella gallinarum, was used theadministration of IgY polyclonal antibodies as immunoglobulin extract, or evenyolk administration had a protective effect against germs invasion. This effect wasnot recorded when a 10 folds higher dose was administered (1x108 CFU. Theprophylactic effect of the administration of polyclonal antibodies is demonstrated.

  1. Measuring T cell-mediated cytotoxicity using fluorogenic caspase substrates.

    Science.gov (United States)

    Chahroudi, A; Silvestri, G; Feinberg, M B

    2003-10-01

    Cytotoxic T lymphocytes (CTLs) play a major role in the immune response against viruses and other intracellular pathogens. In addition, CTLs are implicated in the control of tumor cells in certain settings. Accurate measures of CTL function are of critical importance to study the pathogenesis of infectious diseases and to evaluate the efficacy of new vaccines and immunotherapies. To this end, we have recently developed a flow cytometry-based CTL (FCC) assay that measures the CTL-induced caspase activation within target cells using cell permeable fluorogenic caspase substrates. This novel assay reliably detects, by flow cytometry or fluorescence/confocal microscopy, antigen-specific CTLs in a wide variety of human and murine systems, and is safer and more informative than the standard 51Cr-release assay. In addition, the flow cytometric CTL (FCC) assay provides an alternative method that is often more sensitive and physiologically informative when compared to previously described FCC assays, as it measures a biological indicator of apoptosis within the target cell. The FCC assay may thus represent a useful tool to further understand the molecular and cellular mechanisms that underlie CTL-mediated killing during tumorigenesis or following infection with viruses or other intracellular pathogens.

  2. Mycobacterium avium and purified protein derivative-specific cytotoxicity mediated by CD4+ lymphocytes from healthy HIV-seropositive and-seronegative individuals

    DEFF Research Database (Denmark)

    Ravn, P; Pedersen, B K

    1996-01-01

    mycobacteria. Our objective was to investigate the M.tuberculosis-and M. avium-specific cytotoxic capacity of T cells from healthy, bacille Calmette-Guérin-vaccinated, HIV-seropositive individuals. Blood mononuclear cells were obtained from 10 healthy HIV-seropositive and 10 healthy seronegative persons...... with no history of previous or active mycobacterial infection. Antigen-specific killing of macrophages presenting mycobacterial antigens (purified protein derivative or M. avium culture filtrate) was conducted. The phenotype of the killer cells was determined by a fluorescence-activated cell sorter after antigen...

  3. HETEROGENEITY OF POLYCLONAL IMMUNOGLOBULINS NUCLEASE ACTIVITY IN RHEUMATOID AND REACTIVE ARTHRITIS

    Directory of Open Access Journals (Sweden)

    M. V. Volkova

    2017-01-01

    Full Text Available Catalytic properties of immunoglobulins are widely studied within recent years. It was found that nuclease activity of immunoglobulins is increased in systemic autoimmune diseases. Given some pathogenetic features of rheumatoid arthritis and reactive arthritis, it is appropriate to clarify the nature of nuclease activity in these diseases. Determination of DNAse activity of immunoglobulins with different DNA substrates, and search for specific substrates for distinct clinical entities could serve these purposes. The aim of present work is to determine DNase activity of the polyclonal class G immunoglobulins in rheumatoid and reactive arthritis using various methods.Different methods are used to evaluate nuclease activity. In this paper we present newly developed and modified techniques for determination of DNAse activity of polyclonal IgGs. Particular attention was paid to the electrophoretic method of DNase activity assessment. Polyclonal IgG isolated from blood serum of patients with rheumatoid arthritis and reactive arthritis were used for assays. In this study, we demonstrated the presence of an inhomogeneous DNase activity of immunoglobulins in relation to different substrates.Along with calf thymus DNA, we used bacterial plasmid DNA and PCR products based on bacterial gene sequences. Levels of DNase activity by rivanol clot method with calf thymus DNA as substrate proved to be higher in patients with rheumatoid arthritis than the control values (p < 0.01. DNase abzyme activity in patients with rheumatoid arthritis was elevated, as compared to the patients with reactive arthritis (p < 0.01.When examining ability of the IgG to hydrolyze procaryotic DNA (bacterial plasmid DNA and PCR products, based on bacterial genes, we obtained heterogeneous results. Different Ig samples showed varying degrees of DNA hydrolysis. Abzyme hydrolysis of DNA substrates longer than 700 bp was more pronounced, as compared to short DNA substrates (100 base pairs

  4. Cytotoxicity Testing: Cell Experiments

    Science.gov (United States)

    Grünert, Renate; Westendorf, Aron; Buczkowska, Magdalena; Hänsch, Mareike; Grüunert, Sybil; Bednarski, Patrick J.

    Screening for new anticancer agents has traditionally been done with in vitro cell culture methods. Even in the genomic era of target-driven drug design, screening for cytotoxic activity is still a standard tool in the search for new anticancer agents, especially if the mode of action of a substance is not yet known. A wide variety of cell culture methods with unique end-points are available for testing the anticancer potential of a substance. Each has its advantages and disadvantages, which must be weighed in the decision to use a particular method. Often several complementary methods are used to gain information on the mode of action of a substance.

  5. The kinematics of cytotoxic lymphocytes influence their ability to kill target cells.

    Directory of Open Access Journals (Sweden)

    Purnima Bhat

    Full Text Available Cytotoxic lymphocytes (CTL have been reported to show a range of motility patterns from rapid long-range tracking to complete arrest, but how and whether these kinematics affect their ability to kill target cells is not known. Many in vitro killing assays utilize cell lines and tumour-derived cells as targets, which may be of limited relevance to the kinetics of CTL-mediated killing of somatic cells. Here, live-cell microscopy is used to examine the interactions of CTL and primary murine skin cells presenting antigens. We developed a qualitative and quantitative killing assay using extended-duration fluorescence time-lapse microscopy coupled with large-volume objective software-based data analysis to obtain population data of cell-to-cell interactions, motility and apoptosis. In vivo and ex vivo activated antigen-specific cytotoxic lymphocytes were added to primary keratinocyte targets in culture with fluorometric detection of caspase-3 activation in targets as an objective determinant of apoptosis. We found that activated CTL achieved contact-dependent apoptosis of non-tumour targets after a period of prolonged attachment - on average 21 hours - which was determined by target cell type, amount of antigen, and activation status of CTL. Activation of CTL even without engagement of the T cell receptor was sufficient to mobilise cells significantly above baseline, while the addition of cognate antigen further enhanced their motility. Highly activated CTL showed markedly increased vector displacement, and velocity, and lead to increased antigen-specific target cell death. These data show that the inherent kinematics of CTL correlate directly with their ability to kill non-tumour cells presenting cognate antigen.

  6. In vitro analysis of cytotoxic T cell recruitment mediated by the DC-derived chemokine CCL17

    OpenAIRE

    sprotocols

    2015-01-01

    Dendritic cell (DC) licensing in cross-priming requires physical interaction of several rare immune cells, i.e. cytotoxic T cells (CTL), and cross-presenting DCs. Here we describe a novel in vitro method of analyzing chemokine effects on complex recruitment events in a multi-cellular system. To study CTL recruitment towards CCL17-producing DCs, we established a co-culture system of murine splenic DCs with polyclonal splenic CTL from donor mice, which enables visualization of cell motility and...

  7. Murine Visceral Leishmaniasis: IgM and Polyclonal B-Cell Activation Lead to Disease Exacerbation

    Science.gov (United States)

    Deak, Eszter; Jayakumar, Asha; Wing Cho, Ka; Goldsmith-Pestana, Karen; Dondji, Blaise; Lambris, John D.; McMahon-Pratt, Diane

    2010-01-01

    In visceral leishmaniasis, the draining lymph node (DLN) is the initial site for colonization and establishment of infection after intradermal transmission by the sand fly vector; however, little is known about the developing immune response within this site. Using an intradermal infection model, which allows for parasite visceralization, we have examined the ongoing immune responses in the DLN of BALB/c mice infected with L. infantum. Although not unexpected, at early times post-infection there is a marked B cell expansion in the DLN, which persists throughout infection. However, the characteristics of this response were of interest; as early as day 7 post-infection, polyclonal antibodies (TNP, OVA, chromatin) were observed and the levels appeared comparable to the specific anti-leishmania response. Although B-cell-deficient JHD BALB/c mice are relatively resistant to infection, neither B-cell-derived IL-10 nor B-cell antigen presentation appear to be primarily responsible for the elevated parasitemia. However, passive transfer and reconstitution of JHD BALB/c with secretory immunoglobulins, (IgM or IgG; specific or non-specific immune complexes) results in increased susceptibility to L. infantum infection. Further, JHD BALB/c mice transgenetically reconstituted to secrete IgM demonstrated exacerbated disease in comparison to wild type BALB/c mice as early as 2 days post-infection. Evidence suggests that complement activation (generation of C5a) and signaling via the C5aR (CD88) is related to the disease exacerbation caused by IgM rather than cytokine levels (IL-10 or IFN-γ). Overall these studies indicate that polyclonal B cell activation, which is known to be associated with human visceral leishmaniasis, is an early and intrinsic characteristic of disease and may represent a target for therapeutic intervention. PMID:20213734

  8. Polyclonal VDAC3 antibody decreases human sperm motility: a novel approach to male contraception

    Directory of Open Access Journals (Sweden)

    Asmarinah Asmarinah

    2011-02-01

    Full Text Available Background: Voltage dependent anion channels (VDAC mediate transport of anions, cations and ATP which play an important role in sperm motility. This study was aimed to examine the effect of polyclonal VDAC3 antiserum to human sperm motility.Methods: Polyclonal VDAC3 antiserum used in this study was produced in rabbits by immunization of VDAC3-specific synthetic peptides.  Preimmunserum was collected before immunization and used for control experiment. Recognition of VDAC3 antiserum to antigen in human sperm was performed by western blot. Thirty sperm samples obtained from fertile men which had high quality of sperm motility were washed and collected by Percoll gradient. Sperm motility was assessed by means of evaluation of sperm velocity (seconds per 0.1 mm distance and the number of unmoved sperm (million per ml which were observed 0 minute, 30 minutes and 60 minutes after addition of VDAC3 antiserum and preimmunserum as a control. Both data were analyzed by SPSS 13.0 software.Results: VDAC3 antiserum recognized VDAC3 protein in human sperm. Statistical analysis demonstrated that there were increasing numbers of unmoved spermatozoa after addition of anti-VDAC3 antiserum in vitro for 60 minutes observation compared with preimmunserum (control. We found also that sperm velocity decreased signifi cantly after giving anti-VDAC3 antiserum in vitro for 0 minute, 30 minutes, and 60 minutes compared with pre-immunee serum (control.Conclusion: VDAC3 antiserum can decrease motility of human sperm. and may provide a novel principle of male contraception in the future. (Med J Indones 2011; 20:5-10Keywords: VDAC3 antiserum, sperm, motility, contraception

  9. PRODUCTION OF POLYCLONAL ANTIBODY TO THE COAT PROTEIN OF CITRUS TRISTEZA VIRUS IN CHICKEN EGGS

    Directory of Open Access Journals (Sweden)

    Nurhadi Nurhadi

    2016-10-01

    Full Text Available Citrus tristeza virus (CTV is one of the most destructive diseases in many citrus growing areas of Indonesia. Effective strategies for controlling CTV depend on diagnostic procedure namely enzyme-linked immunosorbent assay (ELISA. Study aimed to purify the CTV antigen and produced its polyclonal antibody. Virion of the severe CTV isolate designated UPM/ T-002 was concentrated by polyethylene glycol (PEG precipitation combined with low speed centrifugation. Semipurified antigen was further purified by sodium dodecyl sulphatepolyacrylamide gel electrophoresis (SDS-PAGE. The specific coat protein (CP band of CTV with molecular weight of 25 kD was excised and eluted using elution buffer containing 0.25 M Tris-HCl pH 6.8 + 0.1% SDS, then used as antigen for injection into 6-month-old female of White Leghorn chicken. Results, showed than the specific polyclonal antibody raised against the 25-kDa CP had a titer of approximately 104, gave low background reaction with healthy plant sap and reacted specifically with CTV isolates. The reaction was equally strong for a severe, a moderate, a mild, and a symptomless isolate, suggesting a broad reaction range of this antibody toward different CTV isolates. Optimal virus titer can be obtained since virus loss during purification could be minimized and the highly purified antigen as an immunogen could be obtained by cutting out the CP band from SDS-PAGE gels. Large amount of highly titer of CTV antibody can be produced in chicken egg. The simplicity of the procedure makes it economically acceptable and technically adoptable because the antibody can be produced in basic laboratory.

  10. Detection of acute inflammation with 111In-labeled nonspecific polyclonal IgG

    International Nuclear Information System (INIS)

    Fischman, A.J.; Rubin, R.H.; Khaw, B.A.

    1988-01-01

    The detection of focal sites of inflammation is an integral part of the clinical evaluation of the febrile patient. When anatomically distinct abscesses are present, lesion detection can be accomplished by standard radiographic techniques, particularly in patients with normal anatomy. At the phlegmon stage, however, and in patients who have undergone surgery, these techniques are considerably less effective. While radionuclide methods, such as Gallium-67 (67Ga)-citrate and Indium-111 (111In)-labeled WBCs have been relatively successful for the detection of early inflammation, neither approach is ideal. In the course of studies addressing the use of specific organism-directed antibodies for imaging experimental infections in animals, we observed that nonspecific polyclonal immunoglobulin G (IgG) localized as well as specific antibodies. Preliminary experiments suggested that the Fc portion of IgG is necessary for effective inflammation localization. Since polyclonal IgG in gram quantities has been safely used for therapy in patients with immune deficiency states, we decided to test whether milligram quantities of radiolabeled IgG could image focal sites of inflammation in humans. Thus far, we have studied a series of 84 patients with suspected lesions in the abdomen, pelvis, vascular grafts, lungs, or bones/joints. In 48 of 52 patients with focal lesions detected by surgery, computed tomography (CT), magnetic resonance imaging (MRI), or ultrasound (US), the IgG scan correctly localized the site, while 31 patients without focal inflammation had no abnormal focal localization of the radiopharmaceutical. Four patients had false negative scans and one patient had a false positive scan. For this small series, the overall sensitivity and specificity were 92% and 95%, respectively. In this report, we review our experience with this exciting new agent

  11. Evaluation of the inflammatory activity in chronic osteomyelitis. Contribution of the scintigraphy with polyclonal antibodies

    International Nuclear Information System (INIS)

    Sapienza, Marcelo Tatit

    1996-01-01

    Active chronic osteomyelitis or complicating osteomyelitis (superimposed on diseases that changes the normal bone structure fractures, post-surgery, prosthesis) can be difficult to diagnose by anatomic radiological imaging modalities, like plain radiograph and CT. These diseases frequently cause also increased bone remodeling, leading to nonspecific uptake of Tc-99m-bone scan agents and gallium-67. New radiopharmaceuticals with greater inflammation/infection avidity and specificity are being developed, including the nonspecific polyclonal immunoglobulin (IgG) labeled with technetium-99. Tc-99m-IgG may be available as a ready to use kit, with no reported side effects, low patient absorbed radiation dose and low cost. The mechanism of IgG uptake at the inflammation site has not been fully elucidated yet. Specific (receptor linking, physico-chemical immunoglobulin properties) and nonspecific mechanisms (enhanced vascular permeability and macromolecular exudate) has been suggested. IgG scintigraphy results are affected by the isotope, labeling procedure adopted and characteristics of the inflammatory focus. Nineteen patients with suspected osteomyelitis (active chronic osteomyelitis or violated bone osteomyelitis) were studied by Tc-99m-IgG scintigraphy (directly labeled polyclonal immunoglobulin, Sandoglobuilina - Sandoz). All patients also underwent standard three-phase bone scintigraphy using methylene diphosphonate (Tc-99m-MDP), gallium-67 scintigraphy and plain radiographs. Infection was found in 8 sites. Sensitivity and specificity for Tc-99m-MDP, gallium-67 and Tc 99m-IgG scintigraphy were, respectively, 88 and 36%, 75 and 73%,88 and 82%. All patients with false positive IgG scintigraphies had previous surgery. Other current scintigraphic procedures used in the diagnosis of osteomyelitis are also reviewed. (author)

  12. [Cytotoxic effect of Vibrio cholerae non-O1 on Vero cells].

    Science.gov (United States)

    Figueroa-Arredondo, P; García-Lozano, H; Gutiérrez-Cogco, L; Valdespino-Gómez, J L

    1994-01-01

    At the present time there is still in Mexico a diarrhoeal outbreak due to Vibrio cholerae O1. In INDRE we have isolated from the same outbreak last year (jan-apr), 70 strains of Vibrio cholerae Non-O1. These were isolated from patients with a diarrhoeal illness different from cholera. Patients were of different ages and sex, and from various geographic areas. The isolated strains were confirmed by serological agglutination test with polyclonal antisera, and they neither belong to O1 serogroup or O139. We assayed all the 70 strains in Vero cells, searching for cytotoxic effect, probably attributed to cholera toxin, or any other toxin. The strains were screened by PCR for cholera toxin gene detection, and negative results were obtained. We have found only one CT-producer strain, but it was a rough one so, we are not able to affirm that is not a V. cholerae O1 serotype. Vibrio cholerae Non-O1 strains, tested in Vero cells assay, produced cytotoxic effect within 24 h. It was found that 48/70 strains (66.6%), had cytotoxic activity, showing rounding and then lysis of cells. From our results we concluded that this cytotoxic effect, is not cholera toxin related, instead we propose it could be due to an unknown virulence factor, probably a different toxin in mexican Vibrio cholerae Non-O1 strains.

  13. Moult-inhibiting fusion protein augments while polyclonal antisera attenuate moult stages and duration in Penaeus monodon

    Digital Repository Service at National Institute of Oceanography (India)

    Vrinda, S.; Jasmin, C.; Sivakumar, K.C.; Jose, B.; Philip, R; BrightSingh, I

    thioredoxin-fused mature MIH I protein (mf-PmMIH I) of P. monodon in a bacterial system and its use as antigen to raise polyclonal antiserum (anti-mf-PmMIH I). The mature MIH I gene of 231 bp, that codes for 77 amino acids, was cloned into the Escherichia coli...

  14. Production of Polyclonal Antiobies to a Recombinant Potato Mop-top Virus Non-structural Triple Gene Block Protein l

    Czech Academy of Sciences Publication Activity Database

    Čeřovská, Noemi; Filigarová, Marie; Pečenková, Tamara

    2006-01-01

    Roč. 154, - (2006), s. 422-427 ISSN 0931-1785 R&D Projects: GA ČR GA522/04/1329 Institutional research plan: CEZ:AV0Z50380511 Keywords : Potato mop-top virus * recombinant protein * triple gene block * polyclonal antibodies Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.817, year: 2006

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

    International Nuclear Information System (INIS)

    Han, Hui; Peng, Ji-Run; Chen, Peng-Cheng; Gong, Lei; Qiao, Shi-Shi; Wang, Wen-Zhen; Cui, Zhu-Qingqing; Yu, Xin; Wei, Yu-Hua; Leng, Xi-Sheng

    2011-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-05

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

  17. Antigen-specific therapies in multiple sclerosis

    NARCIS (Netherlands)

    Noort, J.M. van

    1998-01-01

    Multiple sclerosis is the major neurological disease of young adults in the western world, affecting about 1 per 1,000. It is characterised by chronic or recurrent lesions of inflammatory damage in the white matter of the central nervous system. Within such lesions, the protective myelin sheath is

  18. Engineering antigen-specific immunological tolerance.

    Energy Technology Data Exchange (ETDEWEB)

    Kontos, Stephan; Grimm, Alizee J.; Hubbell, Jeffrey A.

    2015-05-01

    Unwanted immunity develops in response to many protein drugs, in autoimmunity, in allergy, and in transplantation. Approaches to induce immunological tolerance aim to either prevent these responses or reverse them after they have already taken place. We present here recent developments in approaches, based on engineered peptides, proteins and biomaterials, that harness mechanisms of peripheral tolerance both prophylactically and therapeutically to induce antigenspecific immunological tolerance. These mechanisms are based on responses of B and T lymphocytes to other cells in their immune environment that result in cellular deletion or ignorance to particular antigens, or in development of active immune regulatory responses. Several of these approaches are moving toward clinical development, and some are already in early stages of clinical testing.

  19. Lymphocyte antibody-dependent cytotoxicity test for evaluation of clinical role of monoclonal anti-D-antibodies for prevention of rhesus sensitization.

    Science.gov (United States)

    Olovnikova, N I; Belkina, E V; Nikolaeva, T L; Miterev, G Yu; Chertkov, I L

    2006-01-01

    Monoclonal antibodies to D antigen were studied in the reaction of antibody-dependent cytotoxicity for evaluation of the possibility of using these antibodies for preventing rhesus sensitization. High hemolytic activity of four anti-D-monoclonal antibodies in the antibody-dependent cytotoxicity test, mediated by their interaction with FcgammaRI, and the capacity to accelerate elimination of D+ erythrocytes from circulation did not provide the immunosuppressive effect. It was hypothesized that monoclonal antibodies for prevention of rhesus sensitization should interact with FcgammaRIII on lymphocytes. These monoclonal antibodies are extremely rare: only 4 of 125 studied antibodies mediated hemolysis in the antibody-dependent cytotoxicity test with lymphocytes, while all polyclonal anti-D-preparations exhibited this activity.

  20. Characterization of polyclonal antibodies against nonstructural protein 9 from the porcine reproductive and respiratory syndrome virus

    Directory of Open Access Journals (Sweden)

    Mengmeng ZHAO,Juanjuan QIAN,Jiexiong XIE,Tiantian CUI,Songling FENG,Guoqiang WANG,Ruining WANG,Guihong ZHANG

    2016-06-01

    Full Text Available Porcine reproductive and respiratory syndrome (PRRS is considered to be one of the most important infectious diseases impacting the swine industry and is characterized by reproductive failure in late term gestation in sows and respiratory disease in pigs of all ages. The nonstructural protein 9 gene, Nsp9, encoding the RNA-dependent RNA polymerase, is generally regarded as fairly conserved when compared to other viral proteins. Antibodies against Nsp9 will be of great importance for the diagnosis and treatment of the causal agent, PRRS virus. A study was undertaken to generate polyclonal antibodies against the immunodominant Nsp9. For this purpose, the Nsp9 was expressed in Escherichia coli and subsequently used as an antigen to immunize New Zealand rabbits. Antiserum was identified via an indirect ELISA, and then verified based on the ability to react with both naturally and artificially expressed Nsp9. Results of virus neutralization test showed that this antiserum could not neutralize the PRRSV. Nevertheless, this antiserum as a diagnostic core reagent should prove invaluable for further investigations into the mechanism of PRRS pathogenesis.

  1. Production, characterization and applications for Toxoplasma gondii-specific polyclonal chicken egg yolk immunoglobulins.

    Directory of Open Access Journals (Sweden)

    Álvaro Ferreira Júnior

    Full Text Available Toxoplasma gondii may cause abortions, ocular and neurological disorders in warm-blood hosts. Immunized mammals are a wide source of hyperimmune sera used in different approaches, including diagnosis and the study of host-parasite interactions. Unfortunately, mammalian antibodies present limitations for its production, such as the necessity for animal bleeding, low yield, interference with rheumatoid factor, complement activation and affinity to Fc mammalian receptors. IgY antibodies avoid those limitations; therefore they could be an alternative to be applied in T. gondii model.In this study we immunized hens with soluble tachyzoite antigens of T. gondii (STAg and purified egg yolk antibodies (IgY by an inexpensive and simple method, with high yield and purity degree. IgY anti-STAg antibodies presented high avidity and were able to recognize a broad range of parasite antigens, although some marked differences were observed in reactivity profile between antibodies produced in immunized hens and mice. Interestingly, IgY antibodies against Neospora caninum and Eimeria spp. did not react to STAg. We also show that IgY antibodies were suitable to detect T. gondii forms in paraffin-embedded sections and culture cell monolayers.Due to its cost-effectiveness, high production yield and varied range of possible applications, polyclonal IgY antibodies are useful tools for studies involving T. gondii.

  2. A methodological approach for production and purification of polyclonal antibody against dog IgG.

    Science.gov (United States)

    Sadeghi, Somayeh; Aghebati-Maleki, Leili; Nozari, Samira; Majidi, Jafar

    2018-01-01

    Antibodies are a class of biomolecules that has an important role in the immune system and lots of applications in biotechnological methods and in pharmaceutics. Production and purification of antibodies in laboratory animals is one of the first ways to manufacture of these prominent tools. The obtained antibodies from these process could be used in various types of bioassay techniques such as enzyme linked immunosorbent assay (ELISA), radioimmunoassay, etc. Also, antibodies employed in diagnostics applications in humans and other animals in order to detect specific antigens. In this study, we aimed to produce and purify anti-dog IgG via immunizing rabbits with dog IgG in combination with Freund's adjuvant. Polyclonal IgG were purified by ion exchange chromatography and then the purified antibody was labeled with horse radish peroxidase (HPR). Direct ELISA was used to determine the optimum titer and cross-reactivity of HRP conjugated IgG. The purity of various IgG preparations and the optimum dilution of prepared HRP conjugated IgG, respectively, was about 95.00% and 1:8000. This study showed that efficiency ion-exchange chromatography could be an appropriate method for purification of IgG antibodies. This antibody could be a useful tool for future dog immune diagnosis tests. This product characterization shown here sets the foundations for future work on dog IgGs.

  3. Production and characterization of polyclonal antibody against a synthetic peptide from β-actin protein

    Directory of Open Access Journals (Sweden)

    Nazila Amini

    2014-06-01

    Full Text Available Objective(s:Antibodies against actin, as one of the most widely studied structural and multifunctional housekeeping proteins in eukaryotic cells, are used as internal loading controls in western blot analyses. The aim of this study was to produce polyclonal antibody against a synthetic peptide derived from N-terminal region of β-actin protein to be used as a protein loading control in western blot and other assay systems. Materials and Methods: A synthetic peptide derived from β-actin protein was designed and conjugated to Keyhole limpet hemocyanin (KLH (and used to immunize a white New Zealand rabbit. The antibody was purified from serum by affinity chromatography column. The purity of the antibody was determined by SDS-PAGE and its ability to recognize the immunizing peptide was measured by ELISA. The reactivity of the antibody with β-actin protein in a panel of different cell lysates was then evaluated by western blot. In addition, the reactivity of the antibody with the corresponding protein was also evaluated by Immunocytochemistry and Immunohistochemistry in different samples. Results: The antibody could recognize the immunizing peptide in ELISA. It could also recognize            β-actin protein in western blot as well as in immunocytochemistry and immunohistochemistry. Conclusion: Our data suggest that this antibody may be used as an internal control in western blot analyses as well as in other immunological applications such as ELISA,immunocytochemistry and immunohistochemistry.

  4. A comprehensive immunoassay for the detection of microcystins in waters based on polyclonal antibodies

    International Nuclear Information System (INIS)

    Sheng Jianwu; He Miao; Shi Hanchang; Qian Yi

    2006-01-01

    Microcystins (MCs) are a group of closely related toxic cyclic heptapeptides produced by common cyanobacteria (blue-green algae), and microcystin-leucine-arginine (MC-LR) is among the most frequent and most toxic microcystin congeners. In this study, a free amino group was introduced to MC-LR at its seventh amino acid residue with 2-mercaptoethylamine, and the product aminoethyl-MC-LR was coupled to bovine serum albumin (BSA) and horseradish peroxidise (HRP) by glutaraldehyde to be complete antigen (MC-LR-BSA) and labelled hapten (MC-LR-HRP), respectively. Polyclonal antibodies against MC-LR were generated by immunization with MC-LR-BSA. A direct competitive enzyme-linked immunosorbent assay (dc-ELISA) was established to detect the MCs in waters, which showed a good cross-reactivity with MC-LR, MC-RR, MC-YR, MC-LF, MC-LW and nodularin, and have a detection limit for MC-LR 0.12 μg L -1 , the 50% inhibition concentration (IC 50 ) for MC-LR was 0.63 ± 0.06 μg L -1 and the quantitative detection range was from 0.17 to 2.32 μg L -1 , the analysis result of water samples showed good recovery and reliability. So the comprehensive and reliable dc-ELISA will well potentially suit for sensitive analysis for total MCs in drinking as well as resource water samples

  5. Immunological Reactivity Using Monoclonal and Polyclonal Antibodies of Autoimmune Thyroid Target Sites with Dietary Proteins

    Directory of Open Access Journals (Sweden)

    Datis Kharrazian

    2017-01-01

    Full Text Available Many hypothyroid and autoimmune thyroid patients experience reactions with specific foods. Additionally, food interactions may play a role in a subset of individuals who have difficulty finding a suitable thyroid hormone dosage. Our study was designed to investigate the potential role of dietary protein immune reactivity with thyroid hormones and thyroid axis target sites. We identified immune reactivity between dietary proteins and target sites on the thyroid axis that includes thyroid hormones, thyroid receptors, enzymes, and transport proteins. We also measured immune reactivity of either target specific monoclonal or polyclonal antibodies for thyroid-stimulating hormone (TSH receptor, 5′deiodinase, thyroid peroxidase, thyroglobulin, thyroxine-binding globulin, thyroxine, and triiodothyronine against 204 purified dietary proteins commonly consumed in cooked and raw forms. Dietary protein determinants included unmodified (raw and modified (cooked and roasted foods, herbs, spices, food gums, brewed beverages, and additives. There were no dietary protein immune reactions with TSH receptor, thyroid peroxidase, and thyroxine-binding globulin. However, specific antigen-antibody immune reactivity was identified with several purified food proteins with triiodothyronine, thyroxine, thyroglobulin, and 5′deiodinase. Laboratory analysis of immunological cross-reactivity between thyroid target sites and dietary proteins is the initial step necessary in determining whether dietary proteins may play a potential immunoreactive role in autoimmune thyroid disease.

  6. Scintigraphy with 99mTc labelled polyclonal human IgG in rheumatoid arthritis patients

    International Nuclear Information System (INIS)

    Stanchev, V.; Batalov, A.; Atanasov, A.

    1999-01-01

    The study design to assess the diagnostic relevance of scintigraphy with 99m Tc labelled polyclonal human IgG (HIG) for detecting active synovitis in rheumatoid arthritis patients. Fifteen patients presenting rheumatoid arthritis and 3 healthy volunteers are studied on digital camera (Diacam, Siemens). Following iv injection of 500 MBq 99m Tc - HIG, a 3- phase scintigraphy of the knee joints is performed and 4 hours later multiple planar views of the peripheral joint are recorded. Scintigraphic data are comparatively studied with the clinical indicators pointing to active synovitis - joint swellings and pain. Markedly expressed 99m Tc - HIG uptake is noted in joints apparently the most actively involved in the arthritis process clinically, whereas most of the joints without evidence of active synovitis revealed background activity only. The obtained scintigraphic results correlate strongly with the clinical indicator joint swelling (93.2%), and somewhat less with the presence of pain (81.5%). 13.5 per cent of the joints without clinically detectable swelling and 25.6% those free of pain are HIG-positive. 99m Tc - HIG scintigraphy is a highly sensitive noninvasive method of detecting active synovitis, promoting objective assessment of the joint inflammatory process in the course of treatment and follow-up study of rheumatoid arthritis patients

  7. Immune reconstitution with two different rabbit polyclonal anti-thymocytes globulins.

    Science.gov (United States)

    Bamoulid, Jamal; Crepin, Thomas; Gaiffe, Emilie; Laheurte, Caroline; Moulin, Bruno; Frimat, Luc; Rieu, Philippe; Mousson, Christiane; Durrbach, Antoine; Heng, Anne-Elisabeth; Rebibou, Jean-Michel; Saas, Philippe; Courivaud, Cécile; Ducloux, Didier

    2017-12-01

    Broad T cell depletion by polyclonal anti-thymocyte globulins (ATG) has been used for many years as a part of immunosuppressive treatment in transplantation. Currently, two different ATG are used in clinical practice, Thymoglobulin and Grafalon. Due to differences in the immunization source, these products contain different specificities and quantity of antibodies. These differences may have clinical consequences. We conducted a nested study in a large prospective multicentric cohort of kidney transplant to determine whether Grafalon-treated and Thymoglobulin-treated patients experience different lymphocyte reconstitution and clinical outcomes. 182 patients matched for age, gender, CMV status, CMV prophylaxis, number of previous transplantation, and maintenance immunosuppressive treatment were included (Thymoglobulin, [n=91]; Grafalon®, [n=91]). One-year post-transplant, recent thymic emigrants were significantly decreased (12±10% vs 21±12%; p<0.001) in Grafalon-treated patients. By contrast, T cell activation (CD38+DR+Ki67+) and senescence (CD8+CD57+CD28-) was increased in Thymoglobulin-treated patients. Compared to Grafalon, Thymoglobulin was not associated with a significantly different rate of acute rejection. CMV disease (p=0.013) was more frequent in Thymoglobulin-treated patients. Grafalon and Thymoglobulin seem to be equivalent to prevent acute rejection. CMV disease is more frequent in Thymoglobulin-treated patients. One year post-transplant immune profile profoundly differs according to the type of ATG. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Glycation of polyclonal IgGs: Effect of sugar excipients during stability studies.

    Science.gov (United States)

    Leblanc, Y; Bihoreau, N; Jube, M; Andre, M-H; Tellier, Z; Chevreux, G

    2016-05-01

    A number of intravenous immunoglobulin preparations are stabilized with sugar additives that may lead over time to undesirable glycation reactions especially in liquid formulation. This study aimed to evaluate the reactivity of sugar excipients on such preparations in condition of temperature, formulation and concentration commonly used for pharmaceutical products. Through an innovative LC-MS method reported to characterize post-translational modifications of IgGs Fc/2 fragments, a stability study of IVIg formulated with reducing and non-reducing sugars has been undertaken. The rate of polyclonal IgGs glycation was investigated during 6months at 5, 25, 30 and 40°C. High levels of glycation were observed with reducing sugars such as glucose and maltose in the first months of the stability study from 25°C. Non-reducing sugars presented a low reactivity even at the highest tested temperature (40°C). Furthermore, a site by site analysis was performed by MS/MS to determine the glycation sites which were mainly identified at Lys246, Lys248 and Lys324. This work points out the high probability of glycation reactions in some commercialized products and describes a useful method to characterize IVIg glycated products issued from reducing sugar excipients. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Production and Characterization of Anti-LH Polyclonal Antibodies for Establishment of Sepharose Solid Phase Radioimmunoassay

    International Nuclear Information System (INIS)

    Ebeid, N.H.; Mehany, N.L.

    2016-01-01

    The present study was designed to achieve the production and characterization of polyclonal antibody of luteinizing hormone (Anti-LH) as a basic component of LH radioimmunoassay (RIA). The main objective was to improve the immunogenicity of LH by conjugation of LH with bovine serum albumin (LH: BSA) as a protein carrier using Ethyl dimethylaminopropyl Carbodiimide (ECDI). Production of Anti-LH was described where LH : BSA immunogen was immunized into three male mature white New-Zealand rabbits through primary immunization and four boosters. The criteria for selecting LH antiserum for liquid phase RIA system were mainly titer, displacement and immuno response profile and followed by partial purification of IgG-LH. The radioiodinated 125 I-LH tracer was carried out using Chloramine-T as an oxidizing agent and the tracer was purified through PD-10 column. The preparation of LH standards was carried out. Coupling of purified IgG-LH to activated Sepharose particles CL-4B was carried out after activation of Sepharose particles with 1,1-carbonyldiimidazole. Extensive studies were carried out to obtain the optimum conditions of using solid phase Sepharose particles to reach the optimum separation efficiency. The results of validation tests revealed that the local solid phase RIA system is precise and accurate to detect LH concentration in human serum to be used as a diagnostic tool in investigating the infertility in the hypothalamic pituitary gonadal disorders

  10. Solid phase radioimmunoassay for detection of malaria antigen. Comparison of monoclonal and polyclonal antibodies

    International Nuclear Information System (INIS)

    Khusmith, S.; Tharavanij, S.; Patarapotikul, J.; Kasemsuth, R.; Bunnag, D.

    1986-01-01

    A solid phase competitive binding radioimmunoassay (RIA) was developed for the detection of Plasmodium falciparum in infected blood. A suspension of NP40 treated red blood cells was mixed with labelled antimalarial IgG, incubated and then added to malarial antigen coated microtitre plate. Antimalarial IgGs were purified either from high titre sera from individuals living in a malaria endemic area in Thailand or from a locally produced monoclonal antibody (MAB) which showed a bright generalized immunofluorescent staining pattern against all blood stages of P. falciparum, including gametocytes. This MAB reacted with 27 of 31 P. falciparum isolates from Thailand. Using dilution of red blood cells from in vitro cultures of P. falciparum, the test was found to detect parasites at levels equivalent to 13 and 2.2 parasites/10 6 red blood cells with labelled polyclonal IgG (PIgG) and labelled monoclonal IgG (MIgG), respectively. No false positive results were obtained among samples from non-malarial subjects. Of the samples that gave negative results upon microscopic examination, 50 and 35% were still positive with RIA using MIgG and PIgG, respectively. There was a correlation between RIA and the number of parasites, especially when MIgG was used. The results indicate that the IgG fraction of sera from individuals with natural acquired immunity to malaria showed a lower degree of sensitivity in parasite detection than the IgG from monoclonal antibody. (author)

  11. Heparin binding domain of antithrombin III: Characterization using a synthetic peptide directed polyclonal antibody

    International Nuclear Information System (INIS)

    Smith, J.W.; Dey, B.; Knauer, D.J.

    1990-01-01

    Antithrombin III (ATIII) is a plasma-borne serine protease inhibitor that apparently forms covalent complexes with thrombin. The interaction between ATIII and thrombin is enhanced several thousandfold by the glycosaminoglycan, heparin. The authors have previously proposed that the heparin binding site of ATIII residues within a region extending from amino acid residues 114-156. Computer-assisted analysis of this region revealed the presence of a 22 amino acid domain (residues 124-145), part of which shows a strong potential for the formation of an amphipathic helix: hydrophobic on one face and highly positively charged on the other. In the presence studies, polyclonal antisera were generated against a synthetic peptide corresponding to residues 124-145 in native human ATIII. Affinity-purified IgG from these antisera, as well as monovalent Fab's derived from them, specifically blocked the binding of heparin to ATIII. Additionally, occupancy of the heparin binding site by these same monovalent and bivalent IgG's at least partially substituted for heparin, accelerating linkage formation between ATIII and thrombin. These results provide the first immunological evidence that region 124-145 is directly involved in the binding of heparin to ATIII and that an antibody-induced conformational change within this region can mediate ATIII activation

  12. Detection and quantification of Duffy antigen on bovine red blood cell membranes using a polyclonal antibody

    Directory of Open Access Journals (Sweden)

    Ana Teresa B.F. Antonangelo

    2012-09-01

    Full Text Available Babesiosis is one of the most important diseases affecting livestock agriculture worldwide. Animals from the subspecies Bos taurus indicus are more resistant to babesiosis than those from Bos taurus taurus. The genera Babesia and Plasmodium are Apicomplexa hemoparasites and share features such as invasion of red blood cells (RBC. The glycoprotein Duffy is the only human erythrocyte receptor for Pasmodium vivax and a mutation which abolishes expression of this glycoprotein on erythrocyte surfaces is responsible for making the majority of people originating from the indigenous populations of West Africa resistant to P. vivax. The current work detected and quantified the Duffy antigen on Bos taurus indicus and Bos taurus taurus erythrocyte surfaces using a polyclonal antibody in order to investigate if differences in susceptibility to Babesia are due to different levels of Duffy antigen expression on the RBCs of these animals, as is known to be the case in human beings for interactions of Plasmodium vivax-Duffy antigen. ELISA tests showed that the antibody that was raised against Duffy antigens detected the presence of Duffy antigen in both subspecies and that the amount of this antigen on those erythrocyte membranes was similar. These results indicate that the greater resistance of B. taurus indicus to babesiosis cannot be explained by the absence or lower expression of Duffy antigen on RBC surfaces.

  13. The role of Tc-99m polyclonal human immunoglobulin G scintigraphy in Graves' ophthalmopathy

    International Nuclear Information System (INIS)

    Ortapamuk, H.; Hosal, B.; Naldoken, S.

    2002-01-01

    The aim of this study was to clarify whether Tc-99m HIG (Polyclonal Human Immunoglobulin G) can image and determine the severity of orbital involvement in patients with Graves' ophthalmopathy. Twenty-six patients between 19 and 56 years old with Graves' ophthalmopathy were examined. All patients received approximately 370 MBq Tc-99m HIG by intravenous (i.v.) injection. Planar and SPECT examination were performed 4 hours after the injection. Visual and semiquantitative evaluations were performed for both orbits by two independent observers. Clinically active ophthalmopathy patients had noticeably increased orbital accumulation of Tc-99m HIG. In patients with inactive disease, and 14 of 19 had no uptake, whereas 5 patients had orbital radioactivity accumulation. The duration of Graves' ophthalmopathy did not correlate with the presence of active ophthalmopathy and Tc-99m HIG grade. There was no correlation between clinical classification and clinical activity (r=278). There was a good correlation between clinical activity and the radioactivity grade with r=0.666 (p=0.01). The clinical classification closely correlated with Tc-99m HIG grade (r=0.423, p=0.05) Tc-99m HIG scan can clearly identified clinically active patients, and subclinical inflammation can be shown by this scintigraphic evaluation. The current preliminary results suggested that Tc-99m HIG SPECT might be useful for the assessment of disease activity in Graves' ophthalmopathy. (author)

  14. Are diamond nanoparticles cytotoxic?

    Science.gov (United States)

    Schrand, Amanda M; Huang, Houjin; Carlson, Cataleya; Schlager, John J; Omacr Sawa, Eiji; Hussain, Saber M; Dai, Liming

    2007-01-11

    Finely divided carbon particles, including charcoal, lampblack, and diamond particles, have been used for ornamental and official tattoos since ancient times. With the recent development in nanoscience and nanotechnology, carbon-based nanomaterials (e.g., fullerenes, nanotubes, nanodiamonds) attract a great deal of interest. Owing to their low chemical reactivity and unique physical properties, nanodiamonds could be useful in a variety of biological applications such as carriers for drugs, genes, or proteins; novel imaging techniques; coatings for implantable materials; and biosensors and biomedical nanorobots. Therefore, it is essential to ascertain the possible hazards of nanodiamonds to humans and other biological systems. We have, for the first time, assessed the cytotoxicity of nanodiamonds ranging in size from 2 to 10 nm. Assays of cell viability such as mitochondrial function (MTT) and luminescent ATP production showed that nanodiamonds were not toxic to a variety of cell types. Furthermore, nanodiamonds did not produce significant reactive oxygen species. Cells can grow on nanodiamond-coated substrates without morphological changes compared to controls. These results suggest that nanodiamonds could be ideal for many biological applications in a diverse range of cell types.

  15. Polyclonal immune responses to antigens associated with cancer signaling pathways and new strategies to enhance cancer vaccines.

    Science.gov (United States)

    Clay, Timothy M; Osada, Takuya; Hartman, Zachary C; Hobeika, Amy; Devi, Gayathri; Morse, Michael A; Lyerly, H Kim

    2011-04-01

    Aberrant signaling pathways are a hallmark of cancer. A variety of strategies for inhibiting signaling pathways have been developed, but monoclonal antibodies against receptor tyrosine kinases have been among the most successful. A challenge for these therapies is therapeutic unresponsiveness and acquired resistance due to mutations in the receptors, upregulation of alternate growth and survival pathways, or inadequate function of the monoclonal antibodies. Vaccines are able to induce polyclonal responses that can have a multitude of affects against the target molecule. We began to explore therapeutic vaccine development to antigens associated with these signaling pathways. We provide an illustrative example in developing therapeutic cancer vaccines inducing polyclonal adaptive immune responses targeting the ErbB family member HER2. Further, we will discuss new strategies to augment the clinical efficacy of cancer vaccines by enhancing vaccine immunogenicity and reversing the immunosuppressive tumor microenvironment.

  16. Cross-Reactivity of Polyclonal Antibodies against Canavalia ensiformis (Jack Bean) Urease and Helicobacter pylori Urease Subunit A Fragments.

    Science.gov (United States)

    Kaminski, Zbigniew Jerzy; Relich, Inga; Konieczna, Iwona; Kaca, Wieslaw; Kolesinska, Beata

    2018-01-01

    Overlapping decapeptide fragments of H. pylori urease subunit A (UreA) were synthesized and tested with polyclonal antibodies against Canavalia ensiformis (Jack bean) urease. The linear epitopes of UreA identified using the dot blot method were then examined using epitope mapping. For this purpose, series of overlapping fragments of UreA, frameshifted ± four amino acid residues were synthesized. Most of the UreA epitopes which reacted with the Jack bean urease polyclonal antibodies had been recognized in previous studies by monoclonal antibodies against H. pylori urease. Fragments 11 - 24, 21 - 33, and 31 - 42 were able to interact with the Jack bean urease antibodies, giving stable immunological complexes. However, the lack of recognition by these antibodies of all the components in the peptide map strongly suggests that a non-continuous (nonlinear) epitope is located on the N-terminal domain of UreA. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

  17. The development and applications of polyclonal and monoclonal antibodies for the detection of illicit drugs in saliva samples

    OpenAIRE

    Fanning, Lorna M.

    2002-01-01

    Anti-tetrahydrocannabinol (THC), anti-cocaine and anti-morphine polyclonal antibodies were produced. These antibodies were successfully applied to an ELISA format for the detection of THC, cocaine, and morphine in saliva samples. Monoclonal antibodies against amphetamine and its derivatives were produced using two different conjugates, amphetamine-bovine serum albumin and methamphetaminebovine serum albumin. Two successful clones were produced, and the antibodies were applied to an ELISA ...

  18. Detection of Giardia duodenalis antigen in human fecal eluates by enzyme-linked immunosorbent assay using polyclonal antibodies

    Directory of Open Access Journals (Sweden)

    Sofía Duque-Beltrán

    2002-12-01

    Full Text Available The present study developed and standardized an enzime-linked immunosorbent assay (ELISA to detect Giardia antigen in feces using rabbit polyclonal antibodies. Giardia cysts were purified from human fecal samples by sucrose and percoll gradients. Gerbils (Meriones unguiculatus were infected to obtain trophozoites. Rabbits were inoculated with either cyst or trophozoite antigens of 14 Colombian Giardia isolates to develop antibodies against the respective stages. The IgG anti-Giardia were purified by sequential caprylic acid and ammonium sulfate precipitation. A portion of these polyclonal antibodies was linked to alkaline phosphatase (conjugate. One hundred and ninety six samples of human feces, from different patients, were tested by parasitologic diagnosis: 69 were positive for Giardia cysts, 56 had no Giardia parasites, and 71 revealed parasites other than Giardia. The optimal concentration of polyclonal antibodies for antigen capture was 40 µg/ml and the optimal conjugate dilution was 1:100. The absorbance cut-off value was 0.24. The parameters of the ELISA test for Giardia antigen detection were: sensitivity, 100% (95% CI: 93.4-100%; specificity, 95% (95% CI: 88.6-97.6%; positive predictive value, 91% (95% CI: 81.4-95.9%; and negative predictive value, 100% (95% CI: 96.1-100%. This ELISA will improve the diagnosis of Giardia infections in Colombia and will be useful in following patients after treatment.

  19. Production, purification and characterization of polyclonal antibody against the truncated gK of the duck enteritis virus

    Directory of Open Access Journals (Sweden)

    Zhang Shunchuan

    2010-09-01

    Full Text Available Abstract Duck virus enteritis (DVE is an acute, contagious herpesvirus infection of ducks, geese, and swans, which has produced significant economic losses in domestic and wild waterfowl. With the purpose of decreasing economic losses in the commercial duck industry, studying the unknown glycoprotein K (gK of DEV may be a new method for preferably preventing and curing this disease. So this is the first time to product and purify the rabbit anti-tgK polyclonal antibody. Through the western blot and ELISA assay, the truncated glycoprotein K (tgK has good antigenicity, also the antibody possesses high specificity and affinity. Meanwhile the rabbit anti-tgK polyclonal antibody has the potential to produce subunit vaccines and the functions of neutralizing DEV and anti-DEV infection because of its neutralization titer. Indirect immunofluorescent microscopy using the purified rabbit anti-tgK polyclonal antibody as diagnostic antibody was susceptive to detect a small quantity of antigen in tissues or cells. This approach also provides effective experimental technology for epidemiological investigation and retrospective diagnose of the preservative paraffin blocks.

  20. Neutralization of feline immunodeficiency virus by polyclonal cat antibody: Simultaneous involvement of hypervariable regions 4 and 5 of the surface glycoprotein.

    NARCIS (Netherlands)

    C.H.J. Siebelink (Kees); W. Huisman (Willem); J.A. Karlas (Jos); G.F. Rimmelzwaan (Guus); M.L. Bosch (Marnix); A.D.M.E. Osterhaus (Albert)

    1995-01-01

    textabstractSites involved in antibody-mediated neutralization of feline immunodeficiency virus were mapped by reciprocal exchange of envelope fragments or amino acids between molecular clones of feline immunodeficiency virus with different susceptibilities to neutralization by a polyclonal cat

  1. Improved detection of a staphylococcal infection by monomeric and protein A-purified polyclonal human immunoglobulin

    International Nuclear Information System (INIS)

    Calame, W.

    1993-01-01

    The present study was undertaken to compare the technetium-99m labelled non-specific polyclonal human immunoglobulin (Ig) with 99m Tc-labelled monomeric human immunoglobulin (m-Ig), 99m Tc-labelled, protein A-purified, human immunoglobulin (A-IG) and 99m Tc-labelled monomeric, protein A-purified, human immunoglobulin (mA-Ig) as tracer agents for the detection of a thigh infection with Staphylococcus aureus. In vitro the binding of the various tracer agents to bacteria at various intervals was determined. For the in vivo evaluation, mice were infected and received one of the various labelled proteins. Scintigrams were made 0.25, 1, 4 and 24 h later. All 99m Tc-labelled Igs bound to bacteria in vitro: The percentages of binding for the m-Ig (from 1 h onwards) and A-Ig and mA-Ig (from 3 h onwards) were significantly higher than that for Ig. The in vivo target-to-non-target (T/NT) ratios were significantly higher from 4 h onwards for all purified Igs than for Ig. Protein A-purified Ig yielded higher T/NT ratios than m-Ig. Furthermore, the amount of activity in the liver was significantly lower 24 h after administration of m-Ig, A-Ig and mA-Ig than after administration of Ig. It is concluded that in this experimental infection 99m Tc-labelled monomeric Ig localizes a staphylococcal thigh infection better and faster than 99m Tc-labelled unpurified Ig. However, the accumulation obtained with protein A-purified Ig or protein A-purified monomeric Ig was the highest of all tracer agents tested. (orig.)

  2. Tumor-targeted delivery of IL-2 by NKG2D leads to accumulation of antigen-specific CD8+ T cells in the tumor loci and enhanced anti-tumor effects.

    Directory of Open Access Journals (Sweden)

    Tae Heung Kang

    Full Text Available Interleukin-2 (IL-2 has been shown to promote tumor-specific T-cell proliferation and differentiation but systemic administration of IL-2 results in significant toxicity. Therefore, a strategy that can specifically deliver IL-2 to the tumor location may alleviate concerns of toxicity. Because NKG2D ligands have been shown to be highly expressed in many cancer cells but not in healthy cells, we reason that a chimeric protein consisting of NKG2D linked to IL-2 will lead to the specific targeting of IL-2 to the tumor location. Therefore, we created chimeric proteins consisting of NKG2D linked to Gaussia luciferase (GLuc; a marker protein or IL-2 to form NKG2D-Fc-GLuc and NKG2D-Fc-IL2, respectively. We demonstrated that NKG2D linked to GLuc was able to deliver GLuc to the tumor location in vivo. Furthermore, we showed that TC-1 tumor-bearing mice intramuscularly injected with DNA encoding NKG2D-Fc-IL2, followed by electroporation, exhibited an increased number of luciferase-expressing E7-specific CD8+ T cells at the tumor location. More importantly, treatment with the DNA construct encoding NKG2D-Fc-IL2 significantly enhanced the therapeutic anti-tumor effects generated by intradermal vaccination with therapeutic HPV DNA in tumor-bearing mice. Therefore, by linking NKG2D to IL2, we are able to specifically deliver IL-2 to the tumor location, enhancing antigen-specific T-cell immune response and controlling tumor growth. Our approach represents a platform technology to specifically deliver proteins of interest to tumor loci.

  3. Characterization of the antigen-specific CD4+ T cell response induced by prime-boost strategies with CAF01 and CpG adjuvants administered by the intranasal and subcutaneous routes

    Directory of Open Access Journals (Sweden)

    Annalisa eCiabattini

    2015-08-01

    Full Text Available The design of heterologous prime-boost vaccine combinations that optimally shape the immune response is of critical importance for the development of next generation vaccines. Here we tested different prime-boost combinations using the tuberculosis vaccine antigen H56 with CAF01 or CpG ODN 1821 adjuvants, administered by the parenteral and nasal routes. By using peptide-MHC class II tetramers, antigen-specific CD4+ T cells were tracked following primary and booster immunizations. Both parenteral priming with H56 plus CAF01 and nasal priming with H56 plus CpG elicited significant expansion of CD4+ tetramer-positive T cells in the spleen, however only parenterally primed cells responded to booster immunization. Subcutaneous priming with H56 and CAF01 followed by nasal boosting with H56 and CpG showed the greater expansion of CD4+ tetramer-positive T cells in the spleen and lungs compared to all the other homologous and heterologous prime-boost combinations. Nasal boosting exerted a recruitment of primed CD4+ T cells into lungs that was stronger in subcutaneously than nasally primed mice, in accordance with different chemokine receptor expression induced by primary immunization. These data demonstrate that subcutaneous priming is fundamental for eliciting CD4+ T cells that can be efficiently boosted by the nasal route and results in the recruitment of antigen-experienced cells into the lungs. Combination of different vaccine formulations and routes of delivery for priming and boosting is a strategic approach for improving and directing vaccine-induced immune responses.

  4. CHARACTERISTICS OF SIGNALING PATHWAYS MEDIATING A CYTOTOXIC EFFECT OF DENDRITIC CELLS UPON ACTIVATED Т LYMPHOCYTES AND NK CELLS

    Directory of Open Access Journals (Sweden)

    T. V. Tyrinova

    2012-01-01

    Full Text Available Abstract. Cytotoxic/pro-apoptogenic effects of IFNα-induced dendritic cells (IFN-DCs directed against Т-lymphocytes and NK cells were investigated in healthy donors. Using an allogenic MLC system, it was revealed that IFN-DCs induce apoptosis of both activated CD4+ and CD8+ T-lymphocytes, and NK cells. Apoptosis of CD4+ and CD8+ T-lymphocytes induced by their interaction with IFN-DCs was mediated by various signaling pathways. In particular, activated CD4+Т-lymphocytes were most sensitive to TRAIL- и Fas/ FasL-transduction pathways, whereas activated CD8+ T-lymphocytes were induced to apoptosis via TNFα-mediated pathway. PD-1/B7-H1-signaling pathway also played a distinct role in cytotoxic activity of IFNDCs towards both types of T lymphocytes and activated NK cells. The pro-apoptogenic/cytotoxic activity of IFN-DC against activated lymphocytes may be regarded as a mechanism of a feedback regulation aimed at restriction of immune response and maintenance of immune homeostasis. Moreover, upregulation of proapoptogenic molecules on DCs under pathological conditions may lead to suppression of antigen-specific response, thus contributing to the disease progression.

  5. Semi-automated limit-dilution assay and clonal expansion of all T-cell precursors of cytotoxic lymphocytes

    International Nuclear Information System (INIS)

    Wilson, A.; Chen, W.-F.; Scollay, R.; Shortman, K.

    1982-01-01

    A limit-dilution microculture system is described, where almost all precursor T cells of the cytotoxic lineage (CTL-p) develop into extended clones of cytotoxic T cells (CTL), which are then detected with a new radio-autographic 111 In-release assay. The principle is to polyclonally activate all T cells with concanavalin A, to expand the resultant clones over an 8-9 day period in cultures saturated with growth factors, then to detect all clones with cytotoxic function by phytohaemagglutinin mediated lysis of P815 tumour cells. The key variables for obtaining high cloning efficiency are the use of flat-bottomed 96-well culture trays, the use of appropriately irradiated spleen filler cells, and the inclusion of a T-cell growth factor supplement. Cultures are set up at input levels of around one T cell per well. Forty percent of T cells then form CTL clones readily detected by the cytotoxic assay. The lytic activity of the average clone is equivalent to 3000 CTL, but clone size appears to be much larger. The precursor cells are predominantly if not entirely from the Lyt 2 + T-cell subclass and almost all cells of this subclass form cytolytic clones. Analysis of the frequency of positive cultures shows a good fit to the expected Poisson distribution, with no evidence of the CTL-p frequency estimates being distorted by helper or suppressor effects. (Auth.)

  6. Semi-automated limit-dilution assay and clonal expansion of all T-cell precursors of cytotoxic lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, A.; Chen, W.F.; Scollay, R.; Shortman, K. (Walter and Eliza Hall Inst. of Medical Research, Parkville (Australia))

    1982-08-13

    A limit-dilution microculture system is described, where almost all precursor T cells of the cytotoxic lineage (CTL-p) develop into extended clones of cytotoxic T cells (CTL), which are then detected with a new radio-autographic /sup 111/In-release assay. The principle is to polyclonally activate all T cells with concanavalin A, to expand the resultant clones over an 8-9 day period in cultures saturated with growth factors, then to detect all clones with cytotoxic function by phytohaemagglutinin mediated lysis of P815 tumour cells. The key variables for obtaining high cloning efficiency are the use of flat-bottomed 96-well culture trays, the use of appropriately irradiated spleen filler cells, and the inclusion of a T-cell growth factor supplement. Cultures are set up at input levels of around one T cell per well. Forty percent of T cells then form CTL clones readily detected by the cytotoxic assay. The lytic activity of the average clone is equivalent to 3000 CTL, but clone size appears to be much larger. The precursor cells are predominantly if not entirely from the Lyt 2/sup +/ T-cell subclass and almost all cells of this subclass form cytolytic clones. Analysis of the frequency of positive cultures shows a good fit to the expected Poisson distribution, with no evidence of the CTL-p frequency estimates being distorted by helper or suppressor effects.

  7. Dairy cows produce cytokine and cytotoxic T cell responses following vaccination with an antigenic fraction from Streptococcus uberis.

    Science.gov (United States)

    Wedlock, D Neil; Buddle, Bryce M; Williamson, John; Lacy-Hulbert, S Jane; Turner, Sally-Anne; Subharat, Supatsak; Heiser, Axel

    2014-07-15

    Streptococcus uberis is a major cause of mastitis in dairy cows worldwide and currently, there is no vaccine commercially available against this form of mastitis. In the current study, cell-free extracts (CFE) were prepared from each of three different S. uberis strains, designated as #3, #24 and #363 representative of the three main sequence types of S. uberis that cause mastitis in New Zealand. These proteins were formulated into vaccines with Emulsigen-D and the immunogenicity of the vaccines was determined in both calves and dairy cows. Two groups of calves (n=5/group) were vaccinated subcutaneously with CFE from strain #24 or strains #3, #24 and #363 formulated with Emulsigen-D, respectively. A third group (n=5) was vaccinated with CFE from the three strains formulated with Emulsigen-D and also containing recombinant bovine granulocyte macrophage colony-stimulating factor while, a control group (n=5) was not vaccinated. Vaccinated animals produced strong antibody responses to the S. uberis antigens and an antigen-specific cytotoxic effect against blood monocytes/macrophages that had phagocytosed S. uberis, with no significant differences in responses observed between the three vaccinated groups. In a second trial, the safety and immunogenicity of the vaccine containing CFE from all three strains of S. uberis and Emulsigen-D was determined in dairy cows. A group of six cows were vaccinated subcutaneously at 3 and 1 week prior to dry off and revaccinated 2-3 weeks before calving. Immune responses in blood and mammary gland secretions (MGS) were monitored during the dry period and in the subsequent lactation. The vaccine was well tolerated with no adverse effect from vaccination observed in any of the cows. Vaccination induced an antigen-specific cytotoxic effect against blood monocytes/macrophages that had phagocytosed S. uberis, moderate antigen-specific IFN-γ responses in blood and strong antibody responses in both blood and MGS. In conclusion, the results

  8. Measurement of lymphatic function with technetium-99m-labelled polyclonal immunoglobulin

    International Nuclear Information System (INIS)

    Svensson, W.; Glass, D.M.; Bradley, D.; Peters, A.M.

    1999-01-01

    A reliable method for measuring lymph flow in physiological units would be valuable, especially in conditions in which it is uncertain whether lymph flow is increased or decreased. The requirements of a radiopharmaceutical for such measurement include stable radionuclide labelling and rapid access to lymphatic vessels following tissue injection but no access to blood vessels. A soluble macromolecule is likely to come closest to meeting these requirements. Technetium-99m- labelled human polyclonal immunoglobulin (HIG) was therefore investigated firstly in comparison with 99m Tc-labelled human serum albumin (HSA) in patients undergoing routine lymphoscintigraphy and secondly with respect to injection site in a group of volunteers with post-mastectomy oedema (PMO). Subcutaneous injection of 99m Tc-HIG into the web space of a distal extremity gave images in which lymphatic vessels were more clearly defined compared with images obtained after injection of 99m Tc-HSA. Lymph nodes were also more clearly defined, suggesting specific retention of HIG, possibly through Fc-mediated binding. Peripheral blood sampling showed a delayed arrival in blood of radioactivity after 99m Tc-HIG compared with 99m Tc-HSA, although ultimately, the blood recovery of 99m Tc-HIG was significantly higher (P 99m Tc-HSA. Clearance rates of radioactivity from the injection site were not sinificantly different, however, between the two agents. In patients with PMO, web space injection of 99m Tc-HIG gave excellent images of normal lymphatic vessels, of lymph nodes and of abnormal lymph drainage such as dermal backflow in swollen arms. In contrast, neither lymphatic vessels nor lymph nodes were visualised after injection into the skin of the dorsum of the distal forearm. Although there was no difference in clearance rates from the injection sites between normal and swollen arms with either agent in PMO, clearance was significantly faster following injection into the web space (0.11% per minute for

  9. Moult-inhibiting fusion protein augments while polyclonal antisera attenuate moult stages and duration in Penaeus monodon.

    Science.gov (United States)

    Vrinda, S; Jasmin, C; Sivakumar, K C; Jose, Blessy; Philip, Rosamma; Bright Singh, I S

    2016-07-01

    Moulting in crustaceans is regulated by moult-inhibiting hormone (MIH) of the CHH family neuropeptides. The inhibitory functions of MIH have pivotal roles in growth and reproduction of Penaeus monodon. In this study, we report the expression of a thioredoxin-fused mature MIH I protein (mf-PmMIH I) of P. monodon in a bacterial system and its use as antigen to raise polyclonal antiserum (anti-mf-PmMIH I). The mature MIH I gene of 231bp, that codes for 77 amino acids, was cloned into the Escherichia coli thioredoxin gene fusion expression system. The translation expression vector construct (mf-PmMIH I+pET32a+) upon induction produced 29.85kDa mature MIH I fusion protein (mf-PmMIH I). The purified fusion protein was used as exogenous MIH I and as antigen to raise polyclonal antisera. When fusion protein (mf-PmMIH I) was injected into D2 and D3 stages of juvenile shrimp, the moult cycle duration was extended significantly to 16.67±1.03 and 14.67±1.03days respectively compared to that of 11.67±1.03days in controls. Moult duration was further reduced to 8.33±0.82days when polyclonal antiserum (anti-mf-PmMIH I - 1:500 dilutions) was injected. Anti-mf-PmMIH I immunolocalized MIH I producing neurosecretory cells in the eyestalk of P. monodon. In short, the present manuscript reports an innovative means of moult regulation in P. monodon with thioredoxin fused MIH I and antisera developed. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Anti-infectivity of camel polyclonal antibodies against hepatitis C virus in Huh7.5 hepatoma

    Directory of Open Access Journals (Sweden)

    EL-Fakharany Esmail M

    2012-09-01

    Full Text Available Abstract Purpose To extend the study of the camel milk proteins which have antiviral activity against HCV, camel naïve polyclonal IgGs, α-lactalbumin were purified from camel milk and their anti-HCV effect was examined using PBMCs and Huh7.5 cell-lines. They were compared with the activity of human polyclonal IgGs and camel lactoferrin and casein. Material and methods Three types of experiments were performed on PBMCs and HuH7.5 cell. HCV was directly incubated with the purified proteins and then mixed with both cell types, or the proteins were incubated with the cells and then exposed to HCV, or the HCV pre-infected cells were treated with the proteins to inhibit intracellular replication. The proteins were added to cells or virus at different concentrations and time intervals. Results Pretreated PBMCs and Huh7.5 cells with milk proteins were not protected when exposed to HCV infection. The direct interaction between HCV and camel IgGs and camel lactoferrin (cLf led to a complete inhibition of HCV entry into cells, while casein, α-lactalbumin and human IgGs failed to inhibit HCV entry at any tested concentration. Camel IgGs showed ability to recognize HCV peptides with a significant titer (12 × 103 in comparison with human IgGs which failed to do it. Camel lactoferrin was capable of inhibiting the intracellular HCV replication at concentrations of 0.25-1.25 mg/ml. Conclusion Camel milk naïve polyclonal IgGs isolated from camel milk could inhibit the HCV infectivity and demonstrated strong signal against its synthetic peptides. Lactoferrin inhibit the HCV infectivity started from 0.25 mg/ml. However, α-lactalbumin, human IgGs and casein failed to demonstrate any activity against HCV infectivity.

  11. Polyclonal B cell differentiation and loss of gastrointestinal tract germinal centers in the earliest stages of HIV-1 infection.

    Directory of Open Access Journals (Sweden)

    Marc C Levesque

    2009-07-01

    Full Text Available The antibody response to HIV-1 does not appear in the plasma until approximately 2-5 weeks after transmission, and neutralizing antibodies to autologous HIV-1 generally do not become detectable until 12 weeks or more after transmission. Moreover, levels of HIV-1-specific antibodies decline on antiretroviral treatment. The mechanisms of this delay in the appearance of anti-HIV-1 antibodies and of their subsequent rapid decline are not known. While the effect of HIV-1 on depletion of gut CD4(+ T cells in acute HIV-1 infection is well described, we studied blood and tissue B cells soon after infection to determine the effect of early HIV-1 on these cells.In human participants, we analyzed B cells in blood as early as 17 days after HIV-1 infection, and in terminal ileum inductive and effector microenvironments beginning at 47 days after infection. We found that HIV-1 infection rapidly induced polyclonal activation and terminal differentiation of B cells in blood and in gut-associated lymphoid tissue (GALT B cells. The specificities of antibodies produced by GALT memory B cells in acute HIV-1 infection (AHI included not only HIV-1-specific antibodies, but also influenza-specific and autoreactive antibodies, indicating very early onset of HIV-1-induced polyclonal B cell activation. Follicular damage or germinal center loss in terminal ileum Peyer's patches was seen with 88% of follicles exhibiting B or T cell apoptosis and follicular lysis.Early induction of polyclonal B cell differentiation, coupled with follicular damage and germinal center loss soon after HIV-1 infection, may explain both the high rate of decline in HIV-1-induced antibody responses and the delay in plasma antibody responses to HIV-1. Please see later in the article for Editors' Summary.

  12. Regulating gonad inhibition and vitellogenin/vitellin induction in Penaeus monodon using mature GIH fusion protein and polyclonal antisera

    Digital Repository Service at National Institute of Oceanography (India)

    Vrinda, S.; Jasmin, C.; Sivakumar, K.C.; Jose, S.; Jose, B.; Philip, R; BrightSingh, I

    September 2016 Available online 15 September 2016 Keywords: Gonad-inhibiting hormone (GIH) Fusion/chimeric proteinaa r t i c l e i n f o b s t r a c tRegulating gonad inhibition and vitellogen Penaeus monodon using mature GIH fusion polyclonal antisera... restriction site overhangs to match with that of the expression vector; pET32a+. The forward primer (GIH-F- 5′-GAAT TCAACATCCTGGACAGCAAATGCAGGGGTGC-3′) contained EcoR I site (italics) and 29 nucleotide residues encoding the N terminal amino acid residues...

  13. Cytotoxic glucosphingolipid from Celtis Africana.

    Science.gov (United States)

    Perveen, Shagufta; Al-Taweel, Areej Mohammad; Fawzy, Ghada Ahmed; El-Shafae, Azza Muhammed; Khan, Afsar; Proksch, Peter

    2015-05-01

    Literature survey proved the use of the powdered sun-dried bark and roots of Celtis africana for the treatment of cancer in South Africa. The aim of this study was to do further isolation work on the ethyl acetate fraction and to investigate the cytotoxic activities of the various fractions and isolated compound. Cytotoxicity of petroleum ether, chloroform, ethyl acetate, n-butanol fractions and compound 1 were tested on mouse lymphoma cell line L5178Y using the microculture tetrazolium assay. One new glucosphingolipid 1 was isolated from the aerial parts of C. africana. The structure of the new compound was determined by extensive analysis by one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy and mass spectrometry. The ethyl acetate fraction and compound 1 showed strong cytotoxic activity with an EC50 value of 8.3 μg/mL and 7.8 μg/mL, respectively, compared with Kahalalide F positive control (6.3 μg/mL). This is the first report of the occurrence of a cytotoxic glucosphingolipid in family Ulmaceae.

  14. The antioxidant properties, cytotoxicity and monoamine oxidase ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... and the nitroblue tetrazolium (NBT) assay. The cytotoxicity ... The antioxidant activity and cytotoxic effect of the extracts increased with increase ... supplements are concoctions of plants and/or plant .... In vitro antioxidant assay.

  15. Cannabinoid Receptor 2 (CB2 Plays a Role in the Generation of Germinal Center and Memory B Cells, but Not in the Production of Antigen-Specific IgG and IgM, in Response to T-dependent Antigens.

    Directory of Open Access Journals (Sweden)

    Sreemanti Basu

    Full Text Available The cannabinoid receptor 2 (CB2 has been reported to modulate B cell functions including migration, proliferation and isotype class switching. Since these processes are required for the generation of the germinal center (GC and antigen-specific plasma and memory cells following immunization with a T-dependent antigen, CB2 has the capacity to alter the quality and magnitude of T-dependent immune responses. To address this question, we immunized WT and CB2(-/- mice with the T-dependent antigen 4-hydroxy-3-nitrophenylacetyl (NP-chicken-gamma-globulin (CGG and measured GC B cell formation and the generation of antigen-specific B cells and serum immunoglobulin (Ig. While there was a significant reduction in the number of splenic GC B cells in CB2(-/- mice early in the response there was no detectable difference in the number of NP-specific IgM and IgG1 plasma cells. There was also no difference in NP-specific IgM and class switched IgG1 in the serum. In addition, we found no defect in the homing of plasma cells to the bone marrow (BM and affinity maturation, although memory B cell cells in the spleen were reduced in CB2(-/- mice. CB2-deficient mice also generated similar levels of antigen-specific IgM and IgG in the serum as WT following immunization with sheep red blood cells (sRBC. This study demonstrates that although CB2 plays a role in promoting GC and memory B cell formation/maintenance in the spleen, it is dispensable on all immune cell types required for the generation of antigen-specific IgM and IgG in T-dependent immune responses.

  16. Chimeric analysis of EGFP and DsRed2 transgenic mice demonstrates polyclonal maintenance of pancreatic acini.

    Science.gov (United States)

    Ryu, Je-Young; Siswanto, Antoni; Harimoto, Kenichi; Tagawa, Yoh-ichi

    2013-06-01

    The pancreatic islet is an assembly of specific endocrine cells. There are many conflicting reports regarding whether the acinus develops from single or multiple progenitor cells. This study investigated the development and maintenance clonality of the pancreatic acinus and duct using a chimeric analysis with EGFP and DsRed2 transgenic mice. Chimeric mice (G-R mice) were obtained by the aggregation method, using 8-cell stage embryos from EGFP and DsRed2 transgenic mice. The islets from the G-R mice were chimeric and mosaic, consisting of either EGFP- or DsRed2-positive populations, as in previous reports. On the other hand, most acini developed from either EGFP or DsRed2 origin, but some were chimeric. Interestingly, these chimeric acini were clearly separated into two-color regions and were not mosaic. Some large intralobular pancreatic ducts consisting of more than 10 cells were found to be chimeric, but no small ducts made up of less than 9 cells were chimeric. Our histological observations suggest that the pancreatic acinus polyclonally and directionally is maintained by multiple progenitor cells. Pancreatic large ducts also seem to develop polyclonally and might result from the assembly of small ducts that develop from a single origin. These findings provide useful information for further understanding pancreatic maintenance.

  17. A Rapid Detection Method of Brucella with Quantum Dots and Magnetic Beads Conjugated with Different Polyclonal Antibodies

    Science.gov (United States)

    Song, Dandan; Qu, Xiaofeng; Liu, Yushen; Li, Li; Yin, Dehui; Li, Juan; Xu, Kun; Xie, Renguo; Zhai, Yue; Zhang, Huiwen; Bao, Hao; Zhao, Chao; Wang, Juan; Song, Xiuling; Song, Wenzhi

    2017-03-01

    Brucella spp. are facultative intracellular bacteria that cause zoonotic disease of brucellosis worldwide. Traditional methods for detection of Brucella spp. take 48-72 h that does not meet the need of rapid detection. Herein, a new rapid detection method of Brucella was developed based on polyclonal antibody-conjugating quantum dots and antibody-modified magnetic beads. First, polyclonal antibodies IgG and IgY were prepared and then the antibody conjugated with quantum dots (QDs) and immunomagnetic beads (IMB), respectively, which were activated by N-(3-dimethylaminopropyl)- N'-ethylcar-bodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) to form probes. We used the IMB probe to separate the Brucella and labeled by the QD probe, and then detected the fluorescence intensity with a fluorescence spectrometer. The detection method takes 105 min with a limit of detection of 103 CFU/mL and ranges from 10 to 105 CFU/mL ( R 2 = 0.9983), and it can be well used in real samples.

  18. The fluorometric microculture cytotoxicity assay.

    Science.gov (United States)

    Lindhagen, Elin; Nygren, Peter; Larsson, Rolf

    2008-01-01

    The fluorometric microculture cytotoxicity assay (FMCA) is a nonclonogenic microplate-based cell viability assay used for measurement of the cytotoxic and/or cytostatic effect of different compounds in vitro. The assay is based on hydrolysis of the probe, fluorescein diacetate (FDA) by esterases in cells with intact plasma membranes. The assay is available as both a semiautomated 96-well plate setup and a 384-well plate version fully adaptable to robotics. Experimental plates are prepared with a small amount of drug solution and can be stored frozen. Cells are seeded on the plates and cell viability is evaluated after 72 h. The protocol described here is applicable both for cell lines and freshly prepared tumor cells from patients and is suitable both for screening in drug development and as a basis for a predictive test for individualization of anticancer drug therapy.

  19. Cytotoxic diterpenes from Scoparia dulcis.

    Science.gov (United States)

    Ahsan, Monira; Islam, S K N; Gray, Alexander I; Stimson, William H

    2003-07-01

    Four new labdane-derived diterpenes, iso-dulcinol (1), 4-epi-scopadulcic acid B (2), dulcidiol (4), and scopanolal (5), together with two known diterpenes, dulcinol/scopadulciol (3) and scopadiol (6), were isolated from the aerial parts of Scoparia dulcis. The structures were determined by extensive NMR studies. The crude extracts as well as the pure diterpenes showed cytotoxicity against a panel of six human stomach cancer cell lines.

  20. Structure-cytotoxicity relationships for dietary flavonoids

    DEFF Research Database (Denmark)

    Breinholt, V.; Dragsted, L.O.

    1998-01-01

    The cytotoxicity of a large series of dietary flavonoids was tested in a non-tumorigenic mouse and two human cancer cell lines, using the neutral red dye exclusion assay. All compounds tested exhibited a concentration-dependent cytotoxic action in the employed cell lines. The relative cytotoxicity...... of the flavonoids, however, Tvas found to vary greatly among the different cell Lines. With a few exceptions, the investigated flavonoids were more cytotoxic to the human cancer cell lines, than the mouse cell line. The differences in cytotoxicity were accounted for in part by differences in cellular uptake...... and metabolic capacity among the different cell types. In 3T3 cells fairly consistent structure-cytotoxicity relationships were found. The most cytotoxic structures tested in 3T3 cells were flavonoids with adjacent 3',4' hydroxy groups on the B-ring, such as luteolin, quercetin, myricetin, fisetin, eriodictyol...

  1. Comparative cytotoxicity of periodontal bacteria

    International Nuclear Information System (INIS)

    Stevens, R.H.; Hammond, B.F.

    1988-01-01

    The direct cytotoxicity of sonic extracts (SE) from nine periodontal bacteria for human gingival fibroblasts (HGF) was compared. Equivalent dosages (in terms of protein concentration) of SE were used to challenge HGF cultures. The cytotoxic potential of each SE was assessed by its ability to (1) inhibit HGF proliferation, as measured by direct cell counts; (2) inhibit 3H-thymidine incorporation in HGF cultures; or (3) cause morphological alterations of the cells in challenged cultures. The highest concentration (500 micrograms SE protein/ml) of any of the SEs used to challenge the cells was found to be markedly inhibitory to the HGFs by all three of the criteria of cytotoxicity. At the lowest dosage tested (50 micrograms SE protein/ml); only SE from Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, and Fusobacterium nucleatum caused a significant effect (greater than 90% inhibition or overt morphological abnormalities) in the HGFs as determined by any of the criteria employed. SE from Capnocytophaga sputigena, Eikenella corrodens, or Wolinella recta also inhibited cell proliferation and thymidine incorporation at this dosage; however, the degree of inhibition (5-50%) was consistently, clearly less than that of the first group of three organisms named above. The SE of the three other organisms tested (Actinomyces odontolyticus, Bacteroides intermedius, and Streptococcus sanguis) had little or no effect (0-10% inhibition) at this concentration. The data suggest that the outcome of the interaction between bacterial components and normal resident cells of the periodontium is, at least in part, a function of the bacterial species

  2. Comparison of the C-mediating killing activity and C-activating properties of mouse monoclonal and polyclonal antibodies against Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    T. L. Kipnis

    1992-01-01

    Full Text Available A Mouse polyclonal antiserum against Trypanosoma cruzi or its IgG and IgM fractions and five monoclonal antibodies (two IgM, two IgG1 and one IgG2a recognize and combine with membrane components of trypomastigote forms of the parasite as revealed by immunofluorescence. Although all these antibodies sensitize trypomastigotes and prepare them to activate the complement (C system, as measured by consumption of total C, C4, B and C3, only the polyclonal antiserum or its IgG, IgM and Fabμ fragments were able to induce trypanosome lysis by the alternative C pathway.

  3. Recycling endosomes in human cytotoxic T lymphocytes constitute an auxiliary intracellular trafficking pathway for newly synthesized perforin

    Science.gov (United States)

    Lesteberg, Kelsey E.; Orange, Jordan S.; Makedonas, George

    2018-01-01

    Background Although cytotoxic T lymphocytes (CTLs) store perforin within cytoplasmic secretory granules for immediate use, perforin is synthesized anew within hours of TCR stimulation. Previously, we observed new perforin protein at an immunologic synapse independent of secretory lysosomes; herein we aimed to determine how new perforin transits to the synapse if not via lytic granules. Results We analyzed antigen-specific human CTLs via imaging flow cytometry and high-resolution confocal microscopy, with attention to intracellular trafficking components and new perforin. The recycling endosome compartments identified by rab8, rab11a, rab4, and rab37 co-localized with new perforin, as well as the SNAREs vti1b and VAMP4. After ablating the function of the recycling endosome pathway, we observed a relative accumulation of new perforin in rab8 vesicles. Conclusions The recycling endosome pathway may serve as an auxiliary intracellular route for the delivery of new perforin to an immunologic synapse in order to perpetuate a cytotoxic response. PMID:28822075

  4. Dendritic cells transduced with Rsf-1/HBXAP gene generate specific cytotoxic T lymphocytes against ovarian cancer in vitro

    International Nuclear Information System (INIS)

    Sun, Li; Kong, Beihua; Sheng, Xiugui; Sheu, Jim Jinn-Chyuan; Shih, Ie-Ming

    2010-01-01

    Recently, some studies have indicated that Rsf-1/HBXAP plays a role in chromatin remodeling and transcriptional regulation that may contribute to tumorigenesis in ovarian cancer. The present study demonstrates that using dendritic cells (DCs) from human cord blood CD34 + cells transduced with Rsf-1/HBXAP DNA plasmids by nucleofection generate specific cytotoxic T lymphocytes (CTL) against ovarian cancer in vitro. After transfection, DCs were analyzed for Rsf-1/HBXAP mRNA expression by RT-PCR and protein expression by Western blot. Then the DC phenotypes, T-cell stimulatory capacity, endocytic activity and migration capacity were explored by flow cytometry analysis, allogeneic mixed lymphocyte reaction, endocytosis and transwell chemotaxis assay, respectively. After transfection, Rsf-1/HBXAP expression was detected at mRNA and protein levels. Allogeneic T-cell proliferation induced by transfected DCs was obviously higher than non-transfected DCs, but the endocytosis capacity and migratory ability were not different. Rsf-1/HBXAP gene-transduced DCs could induce antigen-specific CTL and generate a very potent cytotoxicity to OVCAR3 cells. These data suggest that Rsf-1/HBXAP gene-transduced DCs may be a potential adjuvant immunotherapy for ovarian cancer in clinical applications.

  5. Suppressive effect on polyclonal B-cell activation of a synthetic peptide homologous to a transmembrane component of oncogenic retroviruses

    Energy Technology Data Exchange (ETDEWEB)

    Mitani, M.; Cianciolo, G.J.; Snyderman, R.; Yasuda, M.; Good, R.A.; Day, N.K.

    1987-01-01

    Purified feline leukemia virus, UV light-inactivated feline leukemia virus, and a synthetic peptide (CKS-17) homologous to a well-conserved region of the transmembrane components of several human and animal retroviruses were each studied for their effect on IgG production by feline peripheral blood lymphocytes. Using a reverse hemolytic plaque assay, both the viable virus and the UV-inactivated feline leukemia virus, but not the CKS-17, activated B lymphocytes to secrete IgG. When staphylococcal protein A, a polyclonal B-cell activator, was used to stimulate IgG synthesis by feline lymphocytes, the viable virus, the UV-inactivated virus, and the CKS-17 peptide each strongly suppressed IgG secretion without compromising viability of the lymphocytes. These finding suggest that the immunosuppressive influences of feline leukemia virus on immunoglobulin synthesis may reside in a conserved portion of the envelope glycoprotein that includes the region homologous to CKS-17.

  6. Suppressive effect on polyclonal B-cell activation of a synthetic peptide homologous to a transmembrane component of oncogenic retroviruses

    International Nuclear Information System (INIS)

    Mitani, M.; Cianciolo, G.J.; Snyderman, R.; Yasuda, M.; Good, R.A.; Day, N.K.

    1987-01-01

    Purified feline leukemia virus, UV light-inactivated feline leukemia virus, and a synthetic peptide (CKS-17) homologous to a well-conserved region of the transmembrane components of several human and animal retroviruses were each studied for their effect on IgG production by feline peripheral blood lymphocytes. Using a reverse hemolytic plaque assay, both the viable virus and the UV-inactivated feline leukemia virus, but not the CKS-17, activated B lymphocytes to secrete IgG. When staphylococcal protein A, a polyclonal B-cell activator, was used to stimulate IgG synthesis by feline lymphocytes, the viable virus, the UV-inactivated virus, and the CKS-17 peptide each strongly suppressed IgG secretion without compromising viability of the lymphocytes. These finding suggest that the immunosuppressive influences of feline leukemia virus on immunoglobulin synthesis may reside in a conserved portion of the envelope glycoprotein that includes the region homologous to CKS-17

  7. Matrix effects in applying mono- and polyclonal ELISA systems to the analysis of weathered oils in contaminated soil.

    Science.gov (United States)

    Pollard, S J T; Farmer, J G; Knight, D M; Young, P J

    2002-01-01

    Commercial mono- and polyclonal enzyme-linked immunosorbent assay (ELISA) systems were applied to the on-site analysis of weathered hydrocarbon-contaminated soils at a former integrated steelworks. Comparisons were made between concentrations of solvent extractable matter (SEM) determined gravimetrically by Soxhlet (dichloromethane) extraction and those estimated immunologically by ELISA determination over a concentration range of 2000-330,000 mg SEM/kg soil dry weight. Both ELISA systems tinder-reported for the more weathered soil samples. Results suggest this is due to matrix effects in the sample rather than any inherent bias in the ELISA systems and it is concluded that, for weathered hydrocarbons typical of steelworks and coke production sites, the use of ELISA requires careful consideration as a field technique. Consideration of the target analyte relative to the composition of the hydrocarbon waste encountered appears critical.

  8. The Cloning and Characterization of the Enolase2 Gene of Gekko japonicus and Its Polyclonal Antibody Preparation

    Directory of Open Access Journals (Sweden)

    Mei Liu

    2013-04-01

    Full Text Available The enolase2 gene is usually expressed in mature neurons and also named neuron specific enolase (NSE. In the present study, we first obtained the NSE gene cDNA sequence by using the RACE method based on the expressed sequence tag (EST fragment from the cDNA library of Gekko japonicus and identified one transcript of about 2.2 kb in central nervous system of Gekko japonicus by Northern blotting. The open reading frame of NSE is 1305 bp, which encodes a 435 amino-acid protein. We further investigated the multi-tissue expression pattern of NSE by RT-PCR and found that the expression of NSE mRNA was very high in brain, spinal cord and low in heart, while it was not detectable in other tissues. The real-time quantitative PCR was used to investigate the time-dependent change in the expression of the NSE mRNA level after gecko spinal cord transection and found it significantly increased at one day, reaching its highest level three days post-injury and then decreasing at the seventh day of the experiment. The recombinant plasmid of pET-32a-NSE was constructed and induced to express His fused NSE protein. The purified NSE protein was used to immunize rabbits to generate polyclonal antisera. The titer of the antiserum was more than 1:65536 determined by ELISA. Western blotting showed that the prepared antibody could specifically recognize the recombinant and endogenous NSE protein. The result of immunohistochemistry revealed that positive signals were present in neurons of the brain and the spinal cord. This study provided the tools of cDNA and polyclonal antibody for studying NSE function in Gekko japonicus.

  9. Quantification of natural populations of Gluconacetobacter diazotrophicus and Herbaspirillum spp. In sugar cane (Saccharum spp.) Using differente polyclonal antibodies

    Science.gov (United States)

    da Silva-Froufe, Lúcia Gracinda; Boddey, Robert Michael; Reis, Veronica Massena

    2009-01-01

    The species Gluconacetobacter diazotrophicus, Herbaspirillum seropedicae and H. rubrisubalbicans are endophytic N2-fixing [diazotrophic] bacteria which colonise not only roots, but also the aerial tissue of sugar cane. However, the technique most commonly used to quantify the populations of these microbes in plants is by culturing serial dilutions of macerates of plant tissues in N free semi-solid media which are only semi-selective for the species/genera [the Most Probable Number (MPN) Technique] and each culture must be further subjected to several tests to identify the isolates at the species level. The use of species-specific polyclonal antibodies with the indirect ELISA (enzyme-linked immunosorbent assay) can be an alternative which is rapid and specific to quantify these populations of bacteria. This study was performed to investigate the viability of adapting the indirect ELISA technique to quantify individually the populations of these three species of diazotroph within the root and shoot tissues of sugarcane. The results showed that species-specific polyclonal antibodies could be obtained by purifying sera in protein-A columns which removed non-specific immuno-globulins. It was possible to quantify the three bacterial species in the Brazilian sugarcane variety SP 70-1143 in numbers above 105 cells per g fresh weight in roots, rhizomes and leaves. The numbers of the different bacterial species evaluated using the ELISA technique were found to be higher than when the same populations were evaluated using the MPN technique, reaching 1400 times greater for G. diazotrophicus and 225 times greater for Herbaspirillum spp. These results constitute the first quantification of Herbaspirillum using immunological techniques. PMID:24031435

  10. Newly Identified TLR9 Stimulant, M6-395 Is a Potent Polyclonal Activator for Murine B Cells.

    Science.gov (United States)

    Park, Mi-Hee; Jung, Yu-Jin; Kim, Pyeung-Hyeun

    2012-02-01

    Toll-like receptors (TLRs) have been extensively studied in recent years. However, functions of these molecules in murine B cell biology are largely unknown. A TLR4 stimulant, LPS is well known as a powerful polyclonal activator for murine B cells. In this study, we explored the effect of a murine TLR9 stimulant, M6-395 (a synthetic CpG ODNs) on B cell proliferation and Ig production. First, M6-395 was much more potent than LPS in augmenting B cell proliferation. As for Ig expression, M6-395 facilitated the expression of both TGF-β1-induced germ line transcript α (GLTα) and IL-4-induced GLTγ1 as levels as those by LPS and Pam3CSK4 (TLR1/2 agonist) : a certain Ig GLT expression is regarded as an indicative of the corresponding isotype switching recombination. However, IgA and IgG1 secretion patterns were quite different--these Ig isotype secretions by M6-395 were much less than those by LPS and Pam3CSK4. Moreover, the increase of IgA and IgG1 production by LPS and Pam3CSK4 was virtually abrogated by M6-395. The same was true for the secretion of IgG3. We found that this unexpected phenomena provoked by M6-395 is attributed, at least in part, to its excessive mitogenic nature. Taken together, these results suggest that M6-395 can act as a murine polyclonal activator but its strong mitogenic activity is unfavorable to Ig isotype switching.

  11. Development and characterization of polyclonal antibodies against the linker region of the telomere-binding protein TRF2

    Directory of Open Access Journals (Sweden)

    Nadya V. Ilicheva

    2018-03-01

    Full Text Available Background: TRF2 (telomeric repeat binding factor 2 is an essential component of the telomere-binding protein complex shelterin. TRF2 induces the formation of a special structure of telomeric DNA and counteracts activation of DNA damage-response pathways telomeres. TRF2 has a poorly characterized linker region (udTRF2 between its homodimerization and DNA-binding domains. Some lines of evidence have shown that this region could be involved in TRF2 interaction with nuclear lamina. Results: In this study, the fragment of the TERF2 gene encoding udTRF2 domain of telomere-binding protein TRF2 was produced by PCR and cloned into the pET32a vector. The resulting plasmid pET32a-udTRF2 was used for the expression of the recombinant udTRF2 in E. coli RosettaBlue (DE3. The protein was isolated and purified using ammonium sulfate precipitation followed by ion-exchange chromatography. The purified recombinant protein udTRF2 was injected into guinea pigs to generate polyclonal antibodies. The ability of anti-udTRF2 antibodies to bind endogenous TRF2 in human skin fibroblasts was tested by western blotting and immunofluorescent staining. Conclusions: In this study, the recombinant protein udTRF2 and antibodies to it were generated. Both protein and antibodies will provide a useful tool for investigation of the functions of the udTRF2 domain and its role in the interaction between TRF2 and nuclear lamina. Keywords: Chromosomes, Molecular cloning, Nuclear lamina, Nucleoprotein complexes, Polyclonal antibodies, Recombinant polypeptide, Shelterin, Telomere-binding protein TRF2, Telomeres, Telomeric DNA, TTAGGG repeats

  12. Quantification of natural populations of Gluconacetobacter diazotrophicus and Herbaspirillum spp. In sugar cane (Saccharum spp.) Using differente polyclonal antibodies.

    Science.gov (United States)

    da Silva-Froufe, Lúcia Gracinda; Boddey, Robert Michael; Reis, Veronica Massena

    2009-10-01

    The species Gluconacetobacter diazotrophicus, Herbaspirillum seropedicae and H. rubrisubalbicans are endophytic N2-fixing [diazotrophic] bacteria which colonise not only roots, but also the aerial tissue of sugar cane. However, the technique most commonly used to quantify the populations of these microbes in plants is by culturing serial dilutions of macerates of plant tissues in N free semi-solid media which are only semi-selective for the species/genera [the Most Probable Number (MPN) Technique] and each culture must be further subjected to several tests to identify the isolates at the species level. The use of species-specific polyclonal antibodies with the indirect ELISA (enzyme-linked immunosorbent assay) can be an alternative which is rapid and specific to quantify these populations of bacteria. This study was performed to investigate the viability of adapting the indirect ELISA technique to quantify individually the populations of these three species of diazotroph within the root and shoot tissues of sugarcane. The results showed that species-specific polyclonal antibodies could be obtained by purifying sera in protein-A columns which removed non-specific immuno-globulins. It was possible to quantify the three bacterial species in the Brazilian sugarcane variety SP 70-1143 in numbers above 10(5) cells per g fresh weight in roots, rhizomes and leaves. The numbers of the different bacterial species evaluated using the ELISA technique were found to be higher than when the same populations were evaluated using the MPN technique, reaching 1400 times greater for G. diazotrophicus and 225 times greater for Herbaspirillum spp. These results constitute the first quantification of Herbaspirillum using immunological techniques.

  13. Quantification of natural populations of Gluconacetobacter diazotrophicus and Herbaspirillum spp. In sugar cane (Saccharum spp. Using differente polyclonal antibodies

    Directory of Open Access Journals (Sweden)

    Lúcia Gracinda da Silva-Froufe

    2009-12-01

    Full Text Available The species Gluconacetobacterdiazotrophicus, Herbaspirillum seropedicae and H. rubrisubalbicans are endophytic N2-fixing [diazotrophic] bacteria which colonise not only roots, but also the aerial tissue of sugar cane. However, the technique most commonly used to quantify the populations of these microbes in plants is by culturing serial dilutions of macerates of plant tissues in N free semi-solid media which are only semi-selective for the species/genera [the Most Probable Number (MPN Technique] and each culture must be further subjected to several tests to identify the isolates at the species level. The use of species-specific polyclonal antibodies with the indirect ELISA (enzyme-linked immunosorbent assay can be an alternative which is rapid and specific to quantify these populations of bacteria. This study was performed to investigate the viability of adapting the indirect ELISA technique to quantify individually the populations of these three species of diazotroph within the root and shoot tissues of sugarcane. The results showed that species-specific polyclonal antibodies could be obtained by purifying sera in protein-A columns which removed non-specific immuno-globulins. It was possible to quantify the three bacterial species in the Brazilian sugarcane variety SP 70-1143 in numbers above 10(5 cells per g fresh weight in roots, rhizomes and leaves. The numbers of the different bacterial species evaluated using the ELISA technique were found to be higher than when the same populations were evaluated using the MPN technique, reaching 1400 times greater for G. diazotrophicus and 225 times greater for Herbaspirillum spp. These results constitute the first quantification of Herbaspirillum using immunological techniques.

  14. Generation of genic diversity among Streptococcus pneumoniae strains via horizontal gene transfer during a chronic polyclonal pediatric infection.

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    N Luisa Hiller

    2010-09-01

    Full Text Available Although there is tremendous interest in understanding the evolutionary roles of horizontal gene transfer (HGT processes that occur during chronic polyclonal infections, to date there have been few studies that directly address this topic. We have characterized multiple HGT events that most likely occurred during polyclonal infection among nasopharyngeal strains of Streptococcus pneumoniae recovered from a child suffering from chronic upper respiratory and middle-ear infections. Whole genome sequencing and comparative genomics were performed on six isolates collected during symptomatic episodes over a period of seven months. From these comparisons we determined that five of the isolates were genetically highly similar and likely represented a dominant lineage. We analyzed all genic and allelic differences among all six isolates and found that all differences tended to occur within contiguous genomic blocks, suggestive of strain evolution by homologous recombination. From these analyses we identified three strains (two of which were recovered on two different occasions that appear to have been derived sequentially, one from the next, each by multiple recombination events. We also identified a fourth strain that contains many of the genomic segments that differentiate the three highly related strains from one another, and have hypothesized that this fourth strain may have served as a donor multiple times in the evolution of the dominant strain line. The variations among the parent, daughter, and grand-daughter recombinant strains collectively cover greater than seven percent of the genome and are grouped into 23 chromosomal clusters. While capturing in vivo HGT, these data support the distributed genome hypothesis and suggest that a single competence event in pneumococci can result in the replacement of DNA at multiple non-adjacent loci.

  15. Cytotoxic Compounds from Aloe megalacantha

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    Negera Abdissa

    2017-07-01

    Full Text Available Phytochemical investigation of the ethyl acetate extract of the roots of Aloe megalacantha led to the isolation of four new natural products—1,8-dimethoxynepodinol (1, aloesaponarin III (2, 10-O-methylchrysalodin (3 and methyl-26-O-feruloyl-oxyhexacosanate (4—along with ten known compounds. All purified metabolites were characterized by NMR, mass spectrometric analyses and comparison with literature data. The isolates were evaluated for their cytotoxic activity against a human cervix carcinoma cell line KB-3-1 and some of them exhibited good activity, with aloesaponarin II (IC50 = 0.98 µM being the most active compound.

  16. High-density fecal Enterococcus faecium colonization in hospitalized patients is associated with the presence of the polyclonal subcluster CC17

    NARCIS (Netherlands)

    Ruiz-Garbajosa, P.; de Regt, M.; Bonten, M.; Baquero, F.; Coque, T. M.; Canton, R.; Harmsen, H. J. M.; Willems, Rob J. L.

    Enterococcus faecium belonging to the polyclonal subcluster CC17, with a typical ampicillin-resistant E. faecium (AREfm) phenotype, have become prevalent among nosocomial infections around the world. High-density intestinal AREfm colonization could be one of the factors contributing to the

  17. Cytotoxicity study of pyrazole derivatives

    Directory of Open Access Journals (Sweden)

    Nusrat Binta Ahasan

    2007-06-01

    Full Text Available Pyrazolone heterocyclic compound, 3-methyl-1-phenyl-2-pyrazoline-5-one 2(a was synthesized by condensation reaction between ethyl acetoacetate and phenyl hydrazine and was converted into their corresponding heterocyclic derivatives 2(b to 2(f2 . Their cytotoxicity effects were measured by brine shrimp lethality bioassay. Among them the compounds 2(b , 2(f1 , and 2(f2 were highly active according to IC50 values 19.50, 19.50 and 20 ppm respectively. The rest of compounds 2(a , 2(c , 2(d1 , and 2(d2 having IC50 values 38, 33.50, 37.50, 36, 37.50 and 36 ppm in that order, were moderately active.

  18. Cytotoxicity study of pyrazole derivatives

    Directory of Open Access Journals (Sweden)

    Nusrat Binta Ahasan and Md. Rabiul Islam

    2007-12-01

    Full Text Available Pyrazolone heterocyclic compound, 3-methyl-1-phenyl-2-pyrazoline-5-one 2(a was synthesized by condensation reaction between ethyl acetoacetate and phenyl hydrazine and was converted into their corresponding heterocyclic derivatives 2(b to 2(f2. Their cytotoxicity effects were measured by brine shrimp lethality bioassay. Among them the compounds 2(b, 2(f1, and 2(f2 were highly active according to IC50 values 19.50, 19.50 and 20 ppm respectively. The rest of compounds 2(a, 2(c, 2(d1, and 2(d2 having IC50 values 38, 33.50, 37.50, 36, 37.50 and 36 ppm in that order, were moderately active.

  19. DNA vaccine-generated duck polyclonal antibodies as a postexposure prophylactic to prevent hantavirus pulmonary syndrome (HPS.

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    Rebecca Brocato

    Full Text Available Andes virus (ANDV is the predominant cause of hantavirus pulmonary syndrome (HPS in South America and the only hantavirus known to be transmitted person-to-person. There are no vaccines, prophylactics, or therapeutics to prevent or treat this highly pathogenic disease (case-fatality 35-40%. Infection of Syrian hamsters with ANDV results in a disease that closely mimics human HPS in incubation time, symptoms of respiratory distress, and disease pathology. Here, we evaluated the feasibility of two postexposure prophylaxis strategies in the ANDV/hamster lethal disease model. First, we evaluated a natural product, human polyclonal antibody, obtained as fresh frozen plasma (FFP from a HPS survivor. Second, we used DNA vaccine technology to manufacture a polyclonal immunoglobulin-based product that could be purified from the eggs of vaccinated ducks (Anas platyrhynchos. The natural "despeciation" of the duck IgY (i.e., Fc removed results in an immunoglobulin predicted to be minimally reactogenic in humans. Administration of ≥ 5,000 neutralizing antibody units (NAU/kg of FFP-protected hamsters from lethal disease when given up to 8 days after intranasal ANDV challenge. IgY/IgYΔFc antibodies purified from the eggs of DNA-vaccinated ducks effectively neutralized ANDV in vitro as measured by plaque reduction neutralization tests (PRNT. Administration of 12,000 NAU/kg of duck egg-derived IgY/IgYΔFc protected hamsters when administered up to 8 days after intranasal challenge and 5 days after intramuscular challenge. These experiments demonstrate that convalescent FFP shows promise as a postexposure HPS prophylactic. Moreover, these data demonstrate the feasibility of using DNA vaccine technology coupled with the duck/egg system to manufacture a product that could supplement or replace FFP. The DNA vaccine-duck/egg system can be scaled as needed and obviates the necessity of using limited blood products obtained from a small number of HPS survivors. This

  20. Consistent manufacturing and quality control of a highly complex recombinant polyclonal antibody product for human therapeutic use.

    Science.gov (United States)

    Frandsen, Torben P; Naested, Henrik; Rasmussen, Søren K; Hauptig, Peter; Wiberg, Finn C; Rasmussen, Lone Kjaer; Jensen, Anne Marie Valentin; Persson, Pia; Wikén, Margareta; Engström, Anders; Jiang, Yun; Thorpe, Susan J; Förberg, Cecilia; Tolstrup, Anne B

    2011-09-01

    The beneficial effect of antibody therapy in human disease has become well established mainly for the treatment of cancer and immunological disorders. The inherent monospecificity of mAbs present limitations to mAb therapy which have become apparent notably in addressing complex entities like infectious agents or heterogenic endogenous targets. For such indications mixtures of antibodies comprising a combination of specificities would convey more potent biological effect which could translate into therapeutic efficacy. Recombinant polyclonal antibodies (rpAb) consisting of a defined number of well-characterized mAbs constitute a new class of target specific antibody therapy. We have developed a cost-efficient cell banking and single-batch manufacturing concept for the production of such products and demonstrate that a complex pAb composition, rozrolimupab, comprising 25 individual antibodies can be manufactured in a highly consistent manner in a scaled-up manufacturing process. We present a strategy for the release and characterization of antibody mixtures which constitute a complete series of chemistry, manufacturing, and control (CMC) analytical methods to address identity, purity, quantity, potency, and general characteristics. Finally we document selected quality attributes of rozrolimupab based on a battery of assays at the genetic-, protein-, and functional level and demonstrate that the manufactured rozrolimupab batches are highly pure and very uniform in their composition. Copyright © 2011 Wiley Periodicals, Inc.

  1. Activity modulation of microbial enzymes by llama (Lama glama) heavy-chain polyclonal antibodies during in vivo immune responses.

    Science.gov (United States)

    Ferrari, A; Weill, F S; Paz, M L; Cela, E M; González Maglio, D H; Leoni, J

    2012-03-01

    Since they were first described in 1993, it was found that recombinant variable fragments (rVHHs) of heavy-chain antibodies (HCAbs) from Camelidae have unusual biophysical properties, as well as a special ability to interact with epitopes that are cryptic for conventional Abs. It has been assumed that in vivo raised polyclonal HCAbs (pHCAbs) should behave in a similar manner than rVHHs; however, this assumption has not been tested sufficiently. Furthermore, our own preliminary work on a single serum sample from a llama immunized with a β-lactamase, has suggested that pHCAbs have no special ability to down-modulate catalytic activity. In this work, we further explored the interaction of pHCAbs from four llamas raised against two microbial enzymes and analyzed it within a short and a long immunization plan. The relative contribution of pHCAbs to serum titer was found to be low compared with that of the most abundant conventional subisotype (IgG(1)), during the whole immunization schedule. Furthermore, pHCAbs not only failed to inhibit the enzymes, but also activated one of them. Altogether, these results suggest that raising high titer inhibitory HCAbs is not a straightforward strategy - neither as a biotechnological strategy nor in the biological context of an immune response against infection - as raising inhibitory rVHHs.

  2. Development of 111In-DTPA-human polyclonal antibody complex for long-term inflammation/infection detection

    International Nuclear Information System (INIS)

    Jalilian, A.R.; Rowshanfarzad, P.; Kamali-Dehghan, M.; Moafian, J.; Akhlaghi, M.; Rajabifar, S.; Mirzaii, M.; Shafaii, K.; Babaii, M.

    2005-01-01

    Human polyclonal antibody (HIgG) was successively labeled with 111-indium chloride after residulation with freshly prepared cyclic DTPA-dianhydride. The best results of the conjugation were obtained by the addition of solid DTPA-dianhydride (0.1-0.3 mg) to 100 μl of the HIgG solution (0.2-0.4 mg/ml) at pH = 6 in phosphate buffer media at 25 o C with continuous stirring for 30 min. Radio-thin-layer chromatography showed an overall radiochemical yield of 96-99% at optimized conditions (specific activity = 300-500 MBq/mg, radiochemical purity >98%). The final isotonic 111 In-DTPA-HIgG complex was checked by radio-TLC to ensure the formation of only one species followed by filtration through a 0.22 μ filter. Preliminary long-term in vivo studies in turpentine-oil induced inflammation in rat model was performed to determine late complex distribution of the radioimmunoconjugate. The target/skin and target/blood ratios were 27 and 51 after 24 h, and 23 and 51 after 110 h, showing a high selectivity of the radiopharmaceutical for inflammatory lesions. (author)

  3. Accurate Point-of-Care Detection of Ruptured Fetal Membranes: Improved Diagnostic Performance Characteristics with a Monoclonal/Polyclonal Immunoassay

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    Linda C. Rogers

    2016-01-01

    Full Text Available Objective Accurate and timely diagnosis of rupture of membranes (ROM is imperative to allow for gestational age-specific interventions. This study compared the diagnostic performance characteristics between two methods used for the detection of ROM as measured in the same patient. Methods Vaginal secretions were evaluated using the conventional fern test as well as a point-of-care monoclonal/polyclonal immunoassay test (ROM Plus® in 75 pregnant patients who presented to labor and delivery with complaints of leaking amniotic fluid. Both tests were compared to analytical confirmation of ROM using three external laboratory tests. Diagnostic performance characteristics were calculated including sensitivity, specificity, positive predictive value (PPV, negative predictive value (NPV, and accuracy. Results Diagnostic performance characteristics uniformly favored ROM detection using the immunoassay test compared to the fern test: sensitivity (100% vs. 77.8%, specificity (94.8% vs. 79.3%, PPV (75% vs. 36.8%, NPV (100% vs. 95.8%, and accuracy (95.5% vs. 79.1%. Conclusions The point-of-care immunoassay test provides improved diagnostic accuracy for the detection of ROM compared to fern testing. It has the potential of improving patient management decisions, thereby minimizing serious complications and perinatal morbidity.

  4. Homeostatic 'bystander' proliferation of human peripheral blood B cells in response to polyclonal T-cell stimulation in vitro.

    Science.gov (United States)

    Jasiulewicz, Aleksandra; Lisowska, Katarzyna A; Pietruczuk, Krzysztof; Frąckowiak, Joanna; Fulop, Tamas; Witkowski, Jacek M

    2015-11-01

    The mechanisms of maintenance of adequate numbers of B lymphocytes and of protective levels of immunoglobulins in the absence of antigenic (re)stimulation remain not fully understood. Meanwhile, our results presented here show that both peripheral blood naive and memory B cells can be activated strongly and non-specifically (in a mitogen-like fashion) in 5-day in vitro cultures of anti-CD3- or concanavalin A (Con A)-stimulated peripheral blood mononuclear cells of healthy people. This polyclonal, bystander activation of the B cells includes multiple divisions of most of them (assessed here by the flow cytometric technique of dividing cell tracking) and significant antibody [immunoglobulin M (IgM) and IgG] secretion. Observed proliferation of the CD19(+) B cells depends on contact with stimulated T helper (Th) cells (via CD40-CD40L interaction) and on the response of B cells to secreted interleukins IL-5, IL-10 and IL-4, and is correlated with the levels of these Th-derived molecules, while it does not involve the ligation of the BCR/CD19 complex. We suggest that the effect might reflect the situation occurring in vivo as the homeostatic proliferation of otherwise non-stimulated, peripheral B lymphocytes, providing an always ready pool for efficient antibody production to any new (or cognate) antigen challenge. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Detection of a local staphylococcal infection in mice with technetium-99m-labeled polyclonal human immunoglobulin

    International Nuclear Information System (INIS)

    Calame, W.; Feitsma, H.I.; Ensing, G.J.; Goedemans, W.T.; Camps, J.A.; van Furth, R.; Pauwels, E.K.

    1991-01-01

    The purpose of this study was to investigate both the ability of 99mTc-labeled polyclonal human immunoglobulin (HIG) to localize an infection and the modes of action involved in this process. Mice, infected with Staphylococcus aureus ATCC 25923 in a thigh muscle, received HIG intravenously. Scintigrams were made 1, 4, and 24 hr later; subsequently the mice were killed and the activity in several organs and thighs was determined. The radiopharmaceutical demonstrated a time-dependent accumulation at the site of infection. It was found that vascular permeability or Fc binding alone could not account for the mode of action of HIG. Neither the origin of Ig (human versus murine) nor the total amount of protein (0.01-1.0 mg Ig per mouse) affected the target-to-background (T/B) ratios. Ratios were not different for leukocytopenic animals. A correlation (p less than 0.001) was demonstrated between the number of bacteria at the site of infection and the T/B ratio. This was also found after antibiotic treatment (p less than 0.02)

  6. Sensitive detection of capsaicinoids using a surface plasmon resonance sensor with anti-homovanillic Acid polyclonal antibodies.

    Science.gov (United States)

    Nakamura, Shingo; Yatabe, Rui; Onodera, Takeshi; Toko, Kiyoshi

    2013-11-13

    Recently, highly functional biosensors have been developed in preparation for possible large-scale terrorist attacks using chemical warfare agents. Practically applicable sensors are required to have various abilities, such as high portability and operability, the capability of performing rapid and continuous measurement, as well as high sensitivity and selectivity. We developed the detection method of capsaicinoids, the main component of some lachrymators, using a surface plasmon resonance (SPR) immunosensor as an on-site detection sensor. Homovanillic acid, which has a vanillyl group similar to capsaicinoids such as capsaicin and dihydrocapsaicin, was bound to Concholepas concholepas hemocyanin (CCH) for use as an immunogen to generate polyclonal antibodies. An indirect competitive assay was carried out to detect capsaicinoids using SPR sensor chips on which different capsaicin analogues were immobilized. For the sensor chip on which 4-hydroxy-3-methoxybenzylamine hydrochloride was immobilized, a detection limit of 150 ppb was achieved. We found that the incubation time was not required and the detection can be completed in five minutes.

  7. Binding of 99mTc-labelled polyclonal human immunoglobulin to bacteria as a mechanism for scintigraphic detection of infection

    International Nuclear Information System (INIS)

    Calame, W.; Furth, R. van

    1991-01-01

    The aim of the present study was to determine whether 99m Tc-labelled polyclonal human immunoglobulin ( 99m Tc-HIG) binds to bacteria in vitro as well as in vivo. In vitro, the binding of 99m Tc-HIG to various gram-positive and gram-negative bacteria was determined. In vivo, mice were infected with Staphylococcus aureus Cowan I (protein A rich) or S. aureus EMS (protein A deficient) in a tigh muscle and then 99m Tc-HIG or 99m Tc-labelled human serum albumin ( 99m Tc-HSA) was administered; scintigrams were made 1, 4 and 18 h later. In vitro binding of 99m Tc-HIG to bacteria was higher for gram-positive than for gram-negative forms. A positive correlation was found between the protein A content and the degree of binding to S. aureus. This was also found in vivo. The accumulation of 99m Tc-HIG at the site of infection was significantly (P 99m Tc-HSA, for both strains of S. aureus. It is concluded that vascular permeability cannot fully explain the accumulation of 99m Tc-HIG at the site of infection and that binding of 99m Tc-HIG to bacteria plays a role in this respect. (orig.)

  8. POLYCLONAL OUTBREAK OF BLOODSTREAM INFECTIONS CAUSED BY Burkholderia cepacia COMPLEX IN HEMATOLOGY AND BONE MARROW TRANSPLANT OUTPATIENT UNITS

    Directory of Open Access Journals (Sweden)

    Icaro Boszczowski

    2014-01-01

    Full Text Available Aim: The objective was to describe an outbreak of bloodstream infections by Burkholderia cepacia complex (Bcc in bone marrow transplant and hematology outpatients. Methods: On February 15, 2008 a Bcc outbreak was suspected. 24 cases were identified. Demographic and clinical data were evaluated. Environment and healthcare workers' (HCW hands were cultured. Species were determined and typed. Reinforcement of hand hygiene, central venous catheter (CVC care, infusion therapy, and maintenance of laminar flow cabinet were undertaken. 16 different HCWs had cared for the CVCs. Multi-dose heparin and saline were prepared on counter common to both units. Findings: 14 patients had B. multivorans (one patient had also B. cenopacia, six non-multivorans Bcc and one did not belong to Bcc. Clone A B. multivorans occurred in 12 patients (from Hematology; in 10 their CVC had been used on February 11/12. Environmental and HCW cultures were negative. All patients were treated with meropenem, and ceftazidime lock-therapy. Eight patients (30% were hospitalized. No deaths occurred. After control measures (multidose vial for single patient; CVC lock with ceftazidime; cleaning of laminar flow cabinet; hand hygiene improvement; use of cabinet to store prepared medication, no new cases occurred. Conclusions: This polyclonal outbreak may be explained by a common source containing multiple species of Bcc, maybe the laminar flow cabinet common to both units. There may have been contamination by B. multivorans (clone A of multi-dose vials.

  9. Sensitive Detection of Capsaicinoids Using a Surface Plasmon Resonance Sensor with Anti-Homovanillic Acid Polyclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Kiyoshi Toko

    2013-11-01

    Full Text Available Recently, highly functional biosensors have been developed in preparation for possible large-scale terrorist attacks using chemical warfare agents. Practically applicable sensors are required to have various abilities, such as high portability and operability, the capability of performing rapid and continuous measurement, as well as high sensitivity and selectivity. We developed the detection method of capsaicinoids, the main component of some lachrymators, using a surface plasmon resonance (SPR immunosensor as an on-site detection sensor. Homovanillic acid, which has a vanillyl group similar to capsaicinoids such as capsaicin and dihydrocapsaicin, was bound to Concholepas concholepas hemocyanin (CCH for use as an immunogen to generate polyclonal antibodies. An indirect competitive assay was carried out to detect capsaicinoids using SPR sensor chips on which different capsaicin analogues were immobilized. For the sensor chip on which 4-hydroxy-3-methoxybenzylamine hydrochloride was immobilized, a detection limit of 150 ppb was achieved. We found that the incubation time was not required and the detection can be completed in five minutes.

  10. Combination of Weight-Bearing Training and Anti-MSTN Polyclonal Antibody Improve Bone Quality In Rats.

    Science.gov (United States)

    Tang, Liang; Gao, Xiaohang; Yang, Xiaoying; Zhang, Didi; Zhang, Xiaojun; Du, Haiping; Han, Yanqi; Sun, Lijun

    2016-12-01

    Weight-bearing exercise is beneficial to bone health. Myostatin (MSTN) deficiency has a positive effect on bone formation. We wondered if a combination of weight-bearing training and polyclonal antibody for MSTN (MsAb) would augment bone formation to a greater degree than single treatment. In this study, rats were randomly assigned to four groups: Control, weight-bearing training (WT), MsAb, and WT+MsAb. The trained rats ran at 15 m/min bearing with 35% of their body weight, 40 min/day (2 min of running followed by 2 min of rest), 6 days/week, for 8 weeks. The rats with MsAb were injected once a week with MsAb for 8 weeks. MicroCT analysis showed that compared with the MsAb group, WT+MsAb significantly enhanced cortical bone mineral density (BMD) (p .05), weight-bearing training significantly increased energy absorption (p weight-bearing training and MsAb have a greater positive effect on bone than treatment with either MsAb or weight-bearing training alone, suggesting that resistance training in combination with MSTN antagonists could be an effective approach for improving bone health and reducing osteoporosis risk.

  11. Cytotoxic Effects of Bangladeshi Medicinal Plant Extracts

    Directory of Open Access Journals (Sweden)

    Shaikh J. Uddin

    2011-01-01

    Full Text Available To investigate the cytotoxic effect of some Bangladeshi medicinal plant extracts, 16 Bangladeshi medicinal plants were successively extracted with n-hexane, dichloromethane, methanol and water. The methanolic and aqueous extracts were screened for cytotoxic activity against healthy mouse fibroblasts (NIH3T3 and three human cancer-cell lines (gastric: AGS; colon: HT-29; and breast: MDA-MB-435S using the MTT assay. Two methanolic extracts (Hygrophila auriculata and Hibiscus tiliaceous and one aqueous extract (Limnophila indica showed no toxicity against healthy mouse fibroblasts, but selective cytotoxicity against breast cancer cells (IC50 1.1–1.6 mg mL−1. Seven methanolic extracts from L. indica, Clerodendron inerme, Cynometra ramiflora, Xylocarpus moluccensis, Argemone mexicana, Ammannia baccifera and Acrostichum aureum and four aqueous extracts from Hygrophila auriculata, Bruguiera gymnorrhiza, X. moluccensis and Aegiceras corniculatum showed low toxicity (IC50 > 2.5 mg mL−1 against mouse fibroblasts but selective cytotoxicity (IC50 0.2–2.3 mg mL−1 against different cancer cell lines. The methanolic extract of Blumea lacera showed the highest cytotoxicity (IC50 0.01–0.08 mg mL−1 against all tested cell lines among all extracts tested in this study. For some of the plants their traditional use as anticancer treatments correlates with the cytotoxic results, whereas for others so far unknown cytotoxic activities were identified.

  12. Investigation of a panel of monoclonal antibodies and polyclonal sera against anthrax toxins resulted in identification of an anti-lethal factor antibody with disease-enhancing characteristics.

    Science.gov (United States)

    Kulshreshtha, Parul; Tiwari, Ashutosh; Priyanka; Joon, Shikha; Sinha, Subrata; Bhatnagar, Rakesh

    2015-12-01

    Hybridomas were created using spleen of mice that were actively immunized with rLFn (recombinant N-terminal domain of lethal factor). Later on, separate group of mice were immunized with rLFn to obtain a polyclonal control for passive immunization studies of monoclonal antibodies. This led to the identification of one cohort of rLFn-immnized mice that harboured disease-enhancing polyclonal antibodies. At the same time, the monoclonal antibodies secreted by all the hybridomas were being tested. Two hybridomas secreted monoclonal antibodies (H10 and H8) that were cross-reactive with EF (edema factor) and LF (lethal factor), while the other two hybridomas secreted LF-specific antibodies (H7 and H11). Single chain variable fragment (LETscFv) was derived from H10 hybridoma. H11 was found to have disease-enhancing property. Combination of H11 with protective monoclonal antibodies (H8 and H10) reduced its disease enhancing nature. This in vitro abrogation of disease-enhancement provides the proof of concept that in polyclonal sera the disease enhancing character of a fraction of antibodies is overshadowed by the protective nature of the rest of the antibodies generated on active immunization. Copyright © 2015. Published by Elsevier Ltd.

  13. Combined in vivo and in vitro approach for the characterization of penicillin-specific polyclonal lymphocyte reactivity: tolerance tests with safe penicillins instead of challenge with culprit drugs.

    Science.gov (United States)

    Sachs, B; Al Masaoudi, T; Merk, H F; Erdmann, S

    2004-10-01

    Amino-penicillins are a major cause of delayed-type reactions to penicillins. The aim of this study was to establish a diagnostic approach for the characterization of the individual penicillin-specific polyclonal lymphocyte reactivity in order to detect side chain-specific sensitization to amino-penicillins. Patients can then be advised to undergo a tolerance test with safe penicillins instead of provocation with culprit penicillins for confirmation of penicillin allergy. We investigated penicillin-specific polyclonal lymphocyte reactivity in nine patients with delayed-type reactions to amino-penicillins by a combined in vivo (patch, prick and intracutaneous tests with delayed readings) and in vitro (lymphocyte transformation test, LTT) approach. A combination of LTT and skin tests improved the sensitivity for the characterization of penicillin-specific polyclonal lymphocyte reactivity and allowed the detection of three different patterns of lymphocyte reactivity. Four patients showed a side chain-specific sensitization to amino-penicillins in vivo and in vitro and were advised to undergo tolerance tests with safe penicillins. Two patients agreed and were exposed to parenteral benzyl-penicillin and oral phenoxymethyl-penicillin which they tolerated without complications. These data suggest that a combined in vivo and in vitro approach is helpful for the detection of side chain-specific sensitization to amino-penicillins. Patients with such sensitization are very likely to tolerate safe penicillins, thereby expanding their therapeutic options when antibiotic treatment is required.

  14. Incidence of Lettuce mosaic virus in lettuce and its detection by polyclonal antibodies produced against recombinant coat protein expressed in Escherichia coli.

    Science.gov (United States)

    Sharma, Prachi; Sharma, Susheel; Singh, Jasvir; Saha, Swati; Baranwal, V K

    2016-04-01

    Lettuce mosaic virus (LMV), a member of the genus Potyvirus of family Potyviridae, causes mosaic disease in lettuce has recently been identified in India. The virus is seed borne and secondary infection occurs through aphids. To ensure virus freedom in seeds it is important to develop diagnostic tools, for serological methods the production of polyclonal antibodies is a prerequisite. The coat protein (CP) gene of LMV was amplified, cloned and expressed using pET-28a vector in Escherichia coli BL21DE3 competent cells. The LMV CP was expressed as a fusion protein containing a fragment of the E. coli His tag. The LMV CP/His protein reacted positively with a commercial antiserum against LMV in an immunoblot assay. Polyclonal antibodies purified from serum of rabbits immunized with the fusion protein gave positive results when LMV infected lettuce (Lactuca sativa) was tested at 1:1000 dilution in PTA-ELISA. These were used for specific detection of LMV in screening lettuce accessions. The efficacy of the raised polyclonal antiserum was high and it can be utilized in quarantine and clean seed production. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. A freeze dried kit formulation for the preparation of 99m Tc labelled human polyclonal IgG for the detection of infection and inflammation

    International Nuclear Information System (INIS)

    Pedraza L, M.

    1996-01-01

    A freeze dried kit formulation for the preparation of 99m Tc-labelled human polyclonal IgG for the detection of infection and inflammation employing direct methods for protein labeling was developed. The method comprises reduction of intrinsic disulphide bridges within the antibody molecule by the use of the reductant 2-mercaptoethanol. Following a subsequent purification, the resulting reduced antibody is labeled via Sn 2+ reduction of pertechnetate in the presence of a weak competing ligand ethane-1-hydroxy-1,1-diphosphonate (EHDP). High labeling efficiencies (>90%) were obtained with high in vitro stability and without effect upon antibody immunoreactivity. Methods of analysis were also established permitting identification of radiochemical impurities which may be present in radiopharmaceutical solution. 99m Tc-polyclonal IgG prepared by the kit method was evaluated for scintigraphic localization of inflammatory lesions and abscesses in rabbits. Data demonstrated that the 99m Tc-polyclonal IgG after kit-reconstitution shows excellent stability and is an effective imaging agent of infection and/or inflammation. (Author)

  16. Molecular cytotoxic mechanisms of anticancer hydroxychalcones.

    Science.gov (United States)

    Sabzevari, Omid; Galati, Giuseppe; Moridani, Majid Y; Siraki, Arno; O'Brien, Peter J

    2004-06-30

    Chalcones are being considered as anticancer agents as they are natural compounds that are particularly cytotoxic towards K562 leukemia or melanoma cells. In this study, we have investigated phloretin, isoliquiritigenin, and 10 other hydroxylated chalcones for their cytotoxic mechanisms towards isolated rat hepatocytes. All hydroxychalcones partly depleted hepatocyte GSH and oxidized GSH to GSSG. These chalcones also caused a collapse of mitochondrial membrane potential and increased oxygen uptake. Furthermore, glycolytic or citric acid cycle substrates prevented cytotoxicity and mitochondrial membrane potential collapse. The highest pKa chalcones were the most effective at collapsing the mitochondrial membrane potential which suggests that the cytotoxic activity of hydroxychalcones are likely because of their ability to uncouple mitochondria.

  17. Produção de anticorpos policlonais anti-ricina Production of polyclonal anti-ricin antibodies

    Directory of Open Access Journals (Sweden)

    Roselayne Ferro Furtado

    2011-02-01

    Full Text Available A ricina é uma proteína bastante tóxica presente nas sementes de mamona que impossibilita o uso da torta de mamona "in natura", como ração. A torta de mamona destoxificada necessita ainda de métodos de análise que garantam a ausência de traços dessa proteína. Objetivou-se, neste trabalho, produzir e avaliar a sensibilidade e especificidade de anticorpos policlonais anti-ricina, para serem empregados como possíveis componentes de métodos sorológicos na detecção de ricina em torta de mamona destoxificada. Foram avaliadas três doses da proteína: 400, 180 e 100 µg cada uma dividida em duas aplicações em coelhos. A primeira dose foi injetada no animal no início do experimento e a segunda após 21 dias. O método de ELISA indicou que as duas doses menores (100 e 180 µg induziram respostas imunológicas primária e secundária com produção de anticorpos específicos. Enquanto a dose maior (400 µg de ricina apresentou uma resposta primária com elevação dos títulos de anticorpos, seguida de uma supressão da resposta. Esse perfil é sugestivo de tolerância imunológica. Pela técnica de Western blotting verificou-se que os anticorpos policlonais produzidos são bastante específicos para a ricina, no entanto, por detectarem ricina na forma nativa e desnaturada não são recomendados para o monitoramento de ricina em torta de mamona destoxificada por tratamento térmico.Ricin is a very toxic protein found in castor bean plants, making it impossible to use natural castor cake as animal food. The detoxificated castor cake needs to be analyzed by methods that ensure the absence of traces of this protein. This work had the objective to produce and to evaluate the sensitivity and specificity of anti-ricin polyclonal antibodies, to be employed as component of sorologic methods as the ELISA in the detection of ricin in detoxificated castor cake. Three doses of protein, 400, 180 and 100 µg were evaluated each one injected twice into

  18. Oxidative Mechanisms of Monocyte-Mediated Cytotoxicity

    Science.gov (United States)

    Weiss, Stephen J.; Lobuglio, Albert F.; Kessler, Howard B.

    1980-01-01

    Human monocytes stimulated with phorbol myristate acetate were able to rapidly destroy autologous erythrocyte targets. Monocyte-mediated cytotoxicity was related to phorbol myristate acetate concentration and monocyte number. Purified preparations of lymphocytes were incapable of mediating erythrocyte lysis in this system. The ability of phorbol myristate acetate-stimulated monocytes to lyse erythrocyte targets was markedly impaired by catalase or superoxide dismutase but not by heat-inactivated enzymes or albumin. Despite a simultaneous requirement for superoxide anion and hydrogen peroxide in the cytotoxic event, a variety of hydroxyl radical and singlet oxygen scavengers did not effect cytolysis. However, tryptophan significantly inhibited cytotoxicity. The myeloperoxidase inhibitor cyanide enhanced erythrocyte destruction, whereas azide reduced it modestly. The inability of cyanide to reduce cytotoxicity coupled with the protective effect of superoxide dismutase suggests that cytotoxicity is independent of the classic myeloperoxidase system. We conclude that monocytes, stimulated with phorbol myristate acetate, generate superoxide anion and hydrogen peroxide, which together play an integral role in this cytotoxic mechanism.

  19. A polyclonal antibody against extracellular loops 1 of chNHE1 blocks avian leukosis virus subgroup J infection.

    Science.gov (United States)

    Meng, Wei; Zhou, Defang; Li, Chengui; Wang, Guihua; Huang, Libo; Cheng, Ziqiang

    2018-05-02

    Avian leukosis virus subgroup J (ALV-J), an oncogenic retrovirus, induces myelocytomas and other various tumors, leading to great economical losses in poultry industry. It is a great challenge to develop effective preventive methods for ALV-J control due to its antigenic variations in the variable regions of envelope. In present study, we generated a mouse polyclonal antibody targeting the first extracellular loop (ECL1) of chicken Na + /H + exchanger isoform 1 (chNHE1), the receptor of ALV-J, to block ALV-J infection in vitro and in vivo. In ALV-J infected DF-1 cells, chNHE1 expression and the intracellular pH (pHi) were up-regulated with "wave" pattern, indicating that the disequilibrium of ALV-J infected cells associated with chNHE1. Next, we validated that ALV-J infection was significantly blocked with time dependent after treating with anti-ECL1 antibody and accordingly the pHi value were recovered, indicating the blockage of ALV-J infection did not affect Na + /H + exchange. Furthermore, in anti-ECL1 antibody treatment chickens that infected by ALV-J, weight gain and immune organs were recovered, and viral loads were significantly decreased, and the tissue injury and inflammation were reduced significantly from 21 to 35 days of age. The study demonstrated that anti-ECL1 antibody effectively blocks ALV-J infection without affecting Na + /H + exchange, and sheds light on a novel strategy for retroviruses control. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Oxaliplatin regulates expression of stress ligands in ovarian cancer cells and modulates their susceptibility to natural killer cell-mediated cytotoxicity.

    Science.gov (United States)

    Siew, Yin-Yin; Neo, Soek-Ying; Yew, Hui-Chuing; Lim, Shun-Wei; Ng, Yi-Cheng; Lew, Si-Min; Seetoh, Wei-Guang; Seow, See-Voon; Koh, Hwee-Ling

    2015-12-01

    Selected cytotoxic chemicals can provoke the immune system to recognize and destroy malignant tumors. Most of the studies on immunogenic cell death are focused on the signals that operate on a series of receptors expressed by dendritic cells to induce tumor antigen-specific T-cell responses. Here, we explored the effects of oxaliplatin, an immunogenic cell death inducer, on the induction of stress ligands and promotion of natural killer (NK) cell-mediated cytotoxicity in human ovarian cancer cells. The results indicated that treatment of tumor cells with oxaliplatin induced the production of type I interferons and chemokines and enhanced the expression of major histocompatibility complex class I-related chains (MIC) A/B, UL16-binding protein (ULBP)-3, CD155 and TNF-related apoptosis-inducing ligand (TRAIL)-R1/R2. Furthermore, oxaliplatin but not cisplatin treatment enhanced susceptibility of ovarian cancer cells to NK cell-mediated cytolysis. In addition, activated NK cells completely abrogated the growth of cancer cells that were pretreated with oxaliplatin. However, cancer cells pretreated with the same concentration of oxaliplatin alone were capable of potentiating regrowth over a period of time. These results suggest an advantage in combining oxaliplatin and NK cell-based therapy in the treatment of ovarian cancer. Further investigation on such potential combination therapy is warranted. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Induction of CML28-specific cytotoxic T cell responses using co-transfected dendritic cells with CML28 DNA vaccine and SOCS1 small interfering RNA expression vector

    International Nuclear Information System (INIS)

    Zhou Hongsheng; Zhang Donghua; Wang Yaya; Dai Ming; Zhang Lu; Liu Wenli; Liu Dan; Tan Huo; Huang Zhenqian

    2006-01-01

    CML28 is an attractive target for antigen-specific immunotherapy. SOCS1 represents an inhibitory control mechanism for DC antigen presentation and the magnitude of adaptive immunity. In this study, we evaluated the potential for inducing CML28-specific cytotoxic T lymphocytes (CTL) responses by dendritic cells (DCs)-based vaccination. We constructed a CML28 DNA vaccine and a SOCS1 siRNA vector and then cotransfect monocyte-derived DCs. Flow cytometry analysis showed gene silencing of SOCS1 resulted in higher expressions of costimulative moleculars in DCs. Mixed lymphocyte reaction (MLR) indicated downregulation of SOCS1 stronger capability to stimulate proliferation of responder cell in DCs. The CTL assay revealed transfected DCs effectively induced autologous CML28-specific CTL responses and the lytic activities induced by SOCS1-silenced DCs were significantly higher compared with those induced by SOCS1-expressing DCs. These results in our study indicates gene silencing of SOCS1 remarkably enhanced the cytotoxicity efficiency of CML28 DNA vaccine in DCs

  2. Immune-mediated bone marrow failure syndromes of progenitor and stem cells: molecular analysis of cytotoxic T cell clones.

    Directory of Open Access Journals (Sweden)

    Ramon Tiu

    2007-03-01

    Full Text Available The unique structure of the T cell receptor (TCR enables molecular identification of individual T cell clones and provides an unique opportunity for the design of molecular diagnostic tests based on the structure of the rearranged TCR chain e.g., using the TCR CDR3 region. Initially, clonal T cell malignancies, including T cell large granular lymphocyte leukemia (T-LGL, mucosis fungoides and peripheral T cell lymphoma were targets for the TCR-based analytic assays such as detection of clonality by T-gamma rearrangement using y-chain-specific PCR or Southern Blotting. Study of these disorders facilitated further analytic concepts and application of rational methods of TCR analysis to investigations of polyclonal T cell-mediated diseases. In hematology, such conditions include graft versus host disease (GvHD and immune-mediated bone marrow failure syndromes. In aplastic anemia (AA, myelodysplastic syndrome (MDS or paroxysmal nocturnal hemoglobinuria (PNH, cytotoxic T cell responses may be directed against certain antigens located on stem or more lineage-restricted progenitor cells in single lineage cytopenias. The nature of the antigenic targets driving polyclonal CTL responses remains unclear. Novel methods of TCR repertoire analysis, include VB flow cytometry, peptide-specific tetramer staining, in vitro stimulation assays and TCR CDR3-specific PCR. Such PCR assay can be either VB family-specific or multiplexed for all VB families. Amplified products can be characterized and quantitated to facilitate detection of the most immunodominant clonotypes. Such clonotypes may serve as markers for the global polyclonal T cell response. Identification of these clonotypes can be performed in blood and tissue biopsy material by various methods. Once immunodominant clonotypes corresponding to pathogenic CTL clones are identified they can serve as surrogate markers for the activity of the pathophysiologic process or even indicate the presence of specific

  3. Antigen delivery by α2-macroglobulin enhances the cytotoxic T lymphocyte response

    Science.gov (United States)

    Bowers, Edith V.; Horvath, Jeffrey J.; Bond, Jennifer E.; Cianciolo, George J.; Pizzo, Salvatore V.

    2009-01-01

    α2M* targets antigens to APCs for rapid internalization, processing, and presentation. When used as an antigen-delivery vehicle, α2M* amplifies MHC class II presentation, as demonstrated by increased antibody titers. Recent evidence, however, suggests that α2M* encapsulation may also enhance antigen-specific CTL immunity. In this study, we demonstrate that α2M*-delivered antigen (OVA) enhances the production of specific in vitro and in vivo CTL responses. Murine splenocytes expressing a transgenic TCR specific for CTL peptide OVA257–264 (SIINFEKL) demonstrated up to 25-fold greater IFN-γ and IL-2 secretion when treated in vitro with α2M*-OVA compared with soluble OVA. The frequency of IFN-γ-producing cells was increased ∼15-fold, as measured by ELISPOT. Expansion of the OVA-specific CD8+ T cell population, as assayed by tetramer binding and [3H]thymidine incorporation, and OVA-specific cell-mediated cytotoxicity, as determined by a flow cytometric assay, were also enhanced significantly by α2M*-OVA. Furthermore, significant CTL responses were observed at antigen doses tenfold lower than those required with OVA alone. Finally, we also observed enhanced humoral and CTL responses by naïve mice following intradermal immunization with α2M*-OVA. These α2M*-OVA-immunized mice demonstrated increased protection against a s.c.-implanted, OVA-expressing tumor, as demonstrated by delayed tumor growth and prolonged animal survival. The observation that α2M*-mediated antigen delivery elicits specific CTL responses suggests the cross-presentation of antigen onto MHC class I. These results support α2M* as an effective antigen-delivery system that may be particularly useful for vaccines based on weakly immunogenic subunits or requiring dose sparing. PMID:19652028

  4. Polymer nanoparticles for cross-presentation of exogenous antigens and enhanced cytotoxic T-lymphocyte immune response

    Directory of Open Access Journals (Sweden)

    Song C

    2016-08-01

    Full Text Available Chanyoung Song,* Young-Woock Noh,* Yong Taik Lim SKKU Advanced Institute of Nanotechnology (SAINT, School of Chemical Engineering, Sungkyunkwan University, Suwon, South Korea *These authors contributed equally to this work Abstract: Effective induction of an antigen-specific cytotoxic T lymphocyte (CTL immune response is one of the key goals of cancer immunotherapy. We report the design and fabrication of polyethylenimine (PEI-coated polymer nanoparticles (NPs as efficient antigen-delivery carriers that can induce antigen cross-presentation and a strong CTL response. After synthesis of poly(d,l-lactide-co-glycolide (PLGA NPs containing ovalbumin (OVA by the double-emulsion solvent-evaporation method, cationic-charged PLGA NPs were generated by coating them with PEI. In a methyl tetrazolium salt assay, no discernible cytotoxic effect of PEI-coated PLGA (OVA NPs was observed. The capacity and mechanism of PEI-coated PLGA (OVA NPs for antigen delivery and cross-presentation on dendritic cells (DCs were determined by fluorescence microscopy and flow cytometry. PEI-coated PLGA (OVA NPs were internalized efficiently via phagocytosis or macropinocytosis in DCs and induced efficient cross-presentation of the antigen on MHC class I molecules via both endosome escape and a lysosomal processing mechanism. The DCs treated with PEI-coated PLGA (OVA NPs induced a release of IL-2 cytokine from OVA-specific CD8-OVA1.3 T cells more efficiently than DCs treated with PLGA (OVA NPs. Therefore, the PEI-coated PLGA (OVA NPs can induce antigen cross-presentation and are expected to be used for induction of a strong CTL immune response and for efficient anticancer immunotherapy. Keywords: antigen delivery, dendritic cells, polymer NPs, vaccine, cross-presentation

  5. Immunoregulatory T cells in man. Histamine-induced suppressor T cells are derived from a Leu 2+ (T8+) subpopulation distinct from that which gives rise to cytotoxic T cells

    International Nuclear Information System (INIS)

    Sansoni, P.; Silverman, E.D.; Khan, M.M.; Melmon, K.L.; Engleman, E.G.

    1985-01-01

    One mechanism of histamine-mediated inhibition of the immune response in man is to activate T suppressor cells that bear the Leu 2 (OKT8) marker. The current study was undertaken to characterize the histamine-induced suppressor cell using a monoclonal antibody (9.3) shown previously to distinguish cytotoxic T cells from antigen-specific suppressor T cells. Leu 2+ cells isolated from peripheral blood were further separated with antibody 9.3 into Leu 2+, 9.3+, and Leu 2+, 9.3- subsets and each subset was incubated with different concentrations of histamine before determining their ability to suppress immune responses in vitro. The results indicate that the Leu 2+, 9.3- subpopulation includes all histamine-induced suppressor cells, that 10(-4) M histamine is the optimal concentration for suppressor cell induction, and that exposure of Leu 2+, 9.3- cells to histamine for 30 s is sufficient to initiate the induction process. After treatment with histamine these cells inhibit both phytohemagglutinin-induced T cell proliferation and pokeweed mitogen-induced B cell differentiation. The suppression of phytohemagglutinin-induced proliferation was resistant to x-irradiation with 1,200 rad, either before or after histamine exposure, suggesting that Leu 2+, 9.3- cells need not proliferate to become suppressor cells or exert suppression. Moreover, suppression by these cells was not due to altered kinetics of the response. Finally, a histamine type 2 receptor antagonist (cimetidine) but not a type 1 receptor antagonist (mepyramine) blocked the induction of suppressor cells. On the basis of these results and our previous studies of antigen specific suppressor cells, we conclude that Leu 2+ suppressor cells in man are derived from a precursor pool that is phenotypically distinct from cells that can differentiate into cytotoxic T cells

  6. Cytotoxicity and intracellular dissolution of nickel nanowires

    KAUST Repository

    Perez, Jose E.

    2015-12-22

    The assessment of cytotoxicity of nanostructures is a fundamental step for their development as biomedical tools. As widely used nanostructures, nickel nanowires (Ni NWs) seem promising candidates for such applications. In this work, Ni NWs were synthesized and then characterized using vibrating sample magnetometry, energy dispersive X-Ray analysis and electron microscopy. After exposure to the NWs, cytotoxicity was evaluated in terms of cell viability, cell membrane damage and induced apoptosis/necrosis on the model human cell line HCT 116. The influence of NW to cell ratio (10:1 to 1000:1) and exposure times up to 72 hours was analyzed for Ni NWs of 5.4 µm in length, as well as for Ni ions. The results show that cytotoxicity markedly increases past 24 hours of incubation. Cellular uptake of NWs takes place through the phagocytosis pathway, with a fraction of the dose of NWs dissolved inside the cells. Cell death results from a combination of apoptosis and necrosis, where the latter is the outcome of the secondary necrosis pathway. The cytotoxicity of Ni ions and Ni NWs dissolution studies suggest a synergistic toxicity between NW aspect ratio and dissolved Ni, with the cytotoxic effects markedly increasing after 24 hours of incubation.

  7. Cytotoxicity and intracellular dissolution of nickel nanowires.

    Science.gov (United States)

    Perez, Jose E; Contreras, Maria F; Vilanova, Enrique; Felix, Laura P; Margineanu, Michael B; Luongo, Giovanni; Porter, Alexandra E; Dunlop, Iain E; Ravasi, Timothy; Kosel, Jürgen

    2016-09-01

    The assessment of cytotoxicity of nanostructures is a fundamental step for their development as biomedical tools. As widely used nanostructures, nickel nanowires (Ni NWs) seem promising candidates for such applications. In this work, Ni NWs were synthesized and then characterized using vibrating sample magnetometry, energy dispersive X-Ray analysis, and electron microscopy. After exposure to the NWs, cytotoxicity was evaluated in terms of cell viability, cell membrane damage, and induced apoptosis/necrosis on the model human cell line HCT 116. The influence of NW to cell ratio (10:1 to 1000:1) and exposure times up to 72 hours was analyzed for Ni NWs of 5.4 μm in length, as well as for Ni ions. The results show that cytotoxicity markedly increases past 24 hours of incubation. Cellular uptake of NWs takes place through the phagocytosis pathway, with a fraction of the dose of NWs dissolved inside the cells. Cell death results from a combination of apoptosis and necrosis, where the latter is the outcome of the secondary necrosis pathway. The cytotoxicity of Ni ions and Ni NWs dissolution studies suggest a synergistic toxicity between NW aspect ratio and dissolved Ni, with the cytotoxic effects markedly increasing after 24 hours of incubation.

  8. Cytotoxicity and intracellular dissolution of nickel nanowires

    KAUST Repository

    Perez, Jose E.; Contreras, Maria F.; Vidal, Enrique Vilanova; Felix Servin, Laura P.; Margineanu, Michael B.; Luongo, Giovanni; Porter, Alexandra E.; Dunlop, Iain E.; Ravasi, Timothy; Kosel, Jü rgen

    2015-01-01

    The assessment of cytotoxicity of nanostructures is a fundamental step for their development as biomedical tools. As widely used nanostructures, nickel nanowires (Ni NWs) seem promising candidates for such applications. In this work, Ni NWs were synthesized and then characterized using vibrating sample magnetometry, energy dispersive X-Ray analysis and electron microscopy. After exposure to the NWs, cytotoxicity was evaluated in terms of cell viability, cell membrane damage and induced apoptosis/necrosis on the model human cell line HCT 116. The influence of NW to cell ratio (10:1 to 1000:1) and exposure times up to 72 hours was analyzed for Ni NWs of 5.4 µm in length, as well as for Ni ions. The results show that cytotoxicity markedly increases past 24 hours of incubation. Cellular uptake of NWs takes place through the phagocytosis pathway, with a fraction of the dose of NWs dissolved inside the cells. Cell death results from a combination of apoptosis and necrosis, where the latter is the outcome of the secondary necrosis pathway. The cytotoxicity of Ni ions and Ni NWs dissolution studies suggest a synergistic toxicity between NW aspect ratio and dissolved Ni, with the cytotoxic effects markedly increasing after 24 hours of incubation.

  9. Polyclonal type II natural killer T cells require PLZF and SAP for their development and contribute to CpG-mediated antitumor response

    Science.gov (United States)

    Zhao, Jie; Weng, Xiufang; Bagchi, Sreya; Wang, Chyung-Ru

    2014-01-01

    CD1d-restricted natural killer T (NKT) cells are innate-like T cells with potent immunomodulatory function via rapid production of both Th1 and Th2 cytokines. NKT cells comprise well-characterized type I NKT cells, which can be detected by α-galactosylceramide-loaded CD1d tetramers, and less-studied type II NKT cells, which do not recognize α-galactosylceramide. Here we characterized type II NKT cells on a polyclonal level by using a Jα18-deficient IL-4 reporter mouse model. This model allows us to track type II NTK cells by the GFP+TCRβ+ phenotype in the thymus and liver. We found type II NKT cells, like type I NKT cells, exhibit an activated phenotype and are dependent on the transcriptional regulator promyelocytic leukemia zinc finger (PLZF) and the adaptor molecule signaling lymphocyte activation molecule-associated protein (SAP) for their development. Type II NKT cells are potently activated by β-D-glucopyranosylceramide (β-GlcCer) but not sulfatide or phospholipids in a CD1d-dependent manner, with the stimulatory capacity of β-GlcCer influenced by acyl chain length. Compared with type I NKT cells, type II NKT cells produce lower levels of IFN-γ but comparable amounts of IL-13 in response to polyclonal T-cell receptor stimulation, suggesting they may play different roles in regulating immune responses. Furthermore, type II NKT cells can be activated by CpG oligodeoxynucletides to produce IFN-γ, but not IL-4 or IL-13. Importantly, CpG-activated type II NKT cells contribute to the antitumor effect of CpG in the B16 melanoma model. Taken together, our data reveal the characteristics of polyclonal type II NKT cells and their potential role in antitumor immunotherapy. PMID:24550295

  10. GoldiRunx and Remembering Cytotoxic Memory.

    Science.gov (United States)

    Mikami, Yohei; Kanno, Yuka

    2018-04-17

    The molecular basis for T cell memory differentiation remains elusive. Wang et al. (2018) identify Runx3 as an initiating transcription factor that specifies regulatory regions required for cytotoxic T cell (CTL) memory differentiation early after TCR signaling and constrains the ability of T-bet to drive terminal effector generation. Published by Elsevier Inc.

  11. Cytotoxicity potentials of eleven Bangladeshi medicinal plants.

    Science.gov (United States)

    Khatun, Amina; Rahman, Mahmudur; Haque, Tania; Rahman, Md Mahfizur; Akter, Mahfuja; Akter, Subarna; Jhumur, Afrin

    2014-01-01

    Various forms of cancer are rising all over the world, requiring newer therapy. The quest of anticancer drugs both from natural and synthetic sources is the demand of time. In this study, fourteen extracts of different parts of eleven Bangladeshi medicinal plants which have been traditionally used for the treatment of different types of carcinoma, tumor, leprosy, and diseases associated with cancer were evaluated for their cytotoxicity for the first time. Extraction was conceded using methanol. Phytochemical groups like reducing sugars, tannins, saponins, steroids, gums, flavonoids, and alkaloids were tested using standard chromogenic reagents. Plants were evaluated for cytotoxicity by brine shrimp lethality bioassay using Artemia salina comparing with standard anticancer drug vincristine sulphate. All the extracts showed potent to moderate cytotoxicity ranging from LC50 2 to 115 µg/mL. The highest toxicity was shown by Hygrophila spinosa seeds (LC50 = 2.93 µg/mL) and the lowest by Litsea glutinosa leaves (LC50 = 114.71 µg/mL) in comparison with standard vincristine sulphate (LC50 = 2.04 µg/mL). Among the plants, the plants traditionally used in different cancer and microbial treatments showed highest cytotoxicity. The results support their ethnomedicinal uses and require advanced investigation to elucidate responsible compounds as well as their mode of action.

  12. Cytotoxicity Potentials of Eleven Bangladeshi Medicinal Plants

    Directory of Open Access Journals (Sweden)

    Amina Khatun

    2014-01-01

    Full Text Available Various forms of cancer are rising all over the world, requiring newer therapy. The quest of anticancer drugs both from natural and synthetic sources is the demand of time. In this study, fourteen extracts of different parts of eleven Bangladeshi medicinal plants which have been traditionally used for the treatment of different types of carcinoma, tumor, leprosy, and diseases associated with cancer were evaluated for their cytotoxicity for the first time. Extraction was conceded using methanol. Phytochemical groups like reducing sugars, tannins, saponins, steroids, gums, flavonoids, and alkaloids were tested using standard chromogenic reagents. Plants were evaluated for cytotoxicity by brine shrimp lethality bioassay using Artemia salina comparing with standard anticancer drug vincristine sulphate. All the extracts showed potent to moderate cytotoxicity ranging from LC50 2 to 115 µg/mL. The highest toxicity was shown by Hygrophila spinosa seeds (LC50=2.93 µg/mL and the lowest by Litsea glutinosa leaves (LC50=114.71 µg/mL in comparison with standard vincristine sulphate (LC50=2.04 µg/mL. Among the plants, the plants traditionally used in different cancer and microbial treatments showed highest cytotoxicity. The results support their ethnomedicinal uses and require advanced investigation to elucidate responsible compounds as well as their mode of action.

  13. SYNTHESIS AND CYTOTOXICITY OF NOVEL LIGNANS

    NARCIS (Netherlands)

    Middel, O; Woerdenbag, H.J.; van Uden, W.; van Oeveren, A.; Jansen, J.F.G.A.; Feringa, B.L.; Konings, A.WT; Pras, N.; Kellogg, R.M

    1995-01-01

    In this study the syntheses of 11 novel lignans are described. Their cytotoxicities are studied in GLC(4), a human small cell lung carcinoma cell line, using the microculture tetrazolium (MTT) assay. Ten of these compounds were substituted with a menthyloxy group on the 5-position of the lactone.

  14. Synthesis and Cytotoxicity of Novel Hexahydrothienocycloheptapyridazinone Derivatives

    Directory of Open Access Journals (Sweden)

    Irene Marchesi

    2009-09-01

    Full Text Available Designed as a new group of tricyclic molecules containing the thienocycloheptapyridazinone ring system, a number of 2N-substituted-hexahydrothienocycloheptapyridazinone derivatives were synthesized and their biological activity evaluated. Among the synthesized compounds, derivatives 7d and 7h were found to possess cytotoxic activity against non-small cell lung cancer and central nervous system cancer cell lines, respectively.

  15. Cytotoxic activity of four Mexican medicinal plants.

    Science.gov (United States)

    Vega-Avila, Elisa; Espejo-Serna, Adolfo; Alarcón-Aguilar, Francisco; Velasco-Lezama, Rodolfo

    2009-01-01

    Ibervillea sonorae Greene, Cucurbita ficifolia Bouché, Tagetes lucida Cav and Justicia spicigera Scheltdd are Mexican native plants used in the treatment of different illnesses. The ethanolic extract of J. spicigera and T. lucida as well as aqueous extracts from I. sonorae, C. ficifolia, T. lucida and J. spicigera were investigated using sulforhodamine B assay. These extracts were assessed using two cell line: T47D (Human Breast cancer) and HeLa (Human cervix cancer). Colchicine was used as the positive control. Data are presented as the dose that inhibited 50% control growth (ED50). All of the assessed extracts were cytotoxic (ED50 < 20 microg/ml) against T47D cell line, meanwhile only the aqueous extract from T. lucida and the ethanolic extract from J. spicigera were cytotoxic to HeLa cell line. Ethanolic extract from J. spicigera presented the best cytotoxic effect. The cytotoxic activity of J. spicigera correlated with one of the popular uses, the treatment of cancer.

  16. Cytotoxic human CD4(+) T cells

    NARCIS (Netherlands)

    van de Berg, Pablo J.; van Leeuwen, Ester M.; ten Berge, Ineke J.; van Lier, Rene

    2008-01-01

    The induction of adaptive immune responses critically depends on helper signals provided by CD4(+) T cells. These signals not only license antigen presenting cells (APC) to activate naïve CD8(+) T cells leading to the formation of vast numbers of cytotoxic T lymphocytes but also support the

  17. Randomized anticancer and cytotoxicity activities of Guibourtia ...

    African Journals Online (AJOL)

    Materials and Methods: The plants were screened for the presence of coumarins, alkaloids, flavonoids, anthraquinones, steroids and terpenoids using thin layer chromatography. Anticancer screening was performed on a panel of three cancer cell lines, while cytotoxicity was determined using a human fibroblast cell line, ...

  18. Cytotoxicity of poly(p-phenylenediamine)

    Czech Academy of Sciences Publication Activity Database

    Kuceková, Z.; Rejmontová, P.; Humpolíček, P.; Kašpárková, V.; Bober, Patrycja; Sáha, P.; Stejskal, Jaroslav

    2017-01-01

    Roč. 71, č. 2 (2017), s. 367-372 ISSN 0366-6352 R&D Projects: GA ČR(CZ) GA13-00270S Institutional support: RVO:61389013 Keywords : cytotoxicity * poly(p-phenylenediamine) * mouse embryonic fibroblasts Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 1.258, year: 2016

  19. Cytotoxicity of Nanoliposomal Cisplatin Coated with Synthesized ...

    African Journals Online (AJOL)

    Purpose: To evaluate the cytotoxicity of pegylated nanoliposomal cisplatin on human ovarian cancer cell line A2780CP. Methods: Synthesized methoxypolyethylene glycol (mPEG) propionaldehyde was characterized by 1Hnuclear magnetic resonance (1H-NMR) and Fourier transform infrared spectroscopy (FTIR) and used ...

  20. The antioxidant properties, cytotoxicity and monoamine oxidase ...

    African Journals Online (AJOL)

    Tarchonanthus camphoratus (camphor bush) has been widely used for numerous medicinal purposes. The aim of the present study was to evaluate the antioxidant properties, cytotoxicity and monoamine oxidase inhibition activities of the crude dichloromethane leaf extract of T. camphoratus. The antioxidant activities were ...

  1. Dissection and manipulation of antigen-specific T cell responses

    NARCIS (Netherlands)

    Schepers, Koen

    2006-01-01

    T cells recognize pathogen-derived antigens and are crucial for fighting pathogens such as viruses and bacteria. In addition, T cells are able to recognize and attack certain types of tumors, in particular virally induced tumors. In this thesis we aimed 1) to obtain more insight into

  2. Polyclonal and monoclonal antibodies specific for the six-helix bundle of the human respiratory syncytial virus fusion glycoprotein as probes of the protein post-fusion conformation

    International Nuclear Information System (INIS)

    Palomo, Concepción; Mas, Vicente; Vázquez, Mónica; Cano, Olga; Luque, Daniel; Terrón, María C.; Calder, Lesley J.; Melero, José A.

    2014-01-01

    Human respiratory syncytial virus (hRSV) has two major surface glycoproteins (G and F) anchored in the lipid envelope. Membrane fusion promoted by hRSV F occurs via refolding from a pre-fusion form to a highly stable post-fusion state involving large conformational changes of the F trimer. One of these changes results in assembly of two heptad repeat sequences (HRA and HRB) into a six-helix bundle (6HB) motif. To assist in distinguishing pre- and post-fusion conformations of hRSV F , we have prepared polyclonal (α-6HB) and monoclonal (R145) rabbit antibodies specific for the 6HB. Among other applications, these antibodies were used to explore the requirements of 6HB formation by isolated protein segments or peptides and by truncated mutants of the F protein. Site-directed mutagenesis and electron microscopy located the R145 epitope in the post-fusion hRSV F at a site distantly located from previously mapped epitopes, extending the repertoire of antibodies that can decorate the F molecule. - Highlights: • Antibodies specific for post-fusion respiratory syncytial virus fusion protein are described. • Polyclonal antibodies were obtained in rabbit inoculated with chimeric heptad repeats. • Antibody binding required assembly of a six-helix bundle in the post-fusion protein. • A monoclonal antibody with similar structural requirements is also described. • Binding of this antibody to the post-fusion protein was visualized by electron microscopy

  3. Highly sensitive determination of diclofenac based on resin beads and a novel polyclonal antibody by using flow injection chemiluminescence competitive immunoassay

    Science.gov (United States)

    Shi, Jing; Xu, Mingxia; Tang, Qinghui; Zhao, Kang; Deng, Anping; Li, Jianguo

    2018-02-01

    A novel flow injection chemiluminescence immunoassay for simple, sensitive and low-cost detection of diclofenac was established based on specific binding of antigen and antibody. Carboxylic resin beads used as solid phase carrier materials provided good biocompatibility and large surface-to-volume ratio for modifying more coating antigen. There was a competitive process between the diclofenac in solution and the immobilized coating antigen to react with the limited binding sites of the polyclonal antibody to form the immunocomplex. The second antibody labelled with horseradish peroxidase was introduced into the immunosensor and trapped by captured polyclonal antibody against diclofenac, which could effectively amplify chemiluminescence signals of luminol-PIP-H2O2. Under optimal conditions, the diclofenac could be detected quantitatively. The chemiluminescence intensity decreased linearly with the logarithm of the diclofenac concentration in the range of 0.1-100 ng mL- 1 with a detection limit of 0.05 ng mL- 1 at a signal-to-noise ratio of 3. The immunosensor exhibited high sensitivity, specificity and acceptable stability. This easy-operated and cost-effective analytical method could be valuable for the diclofenac determination in real water samples.

  4. Radiolabeled, nonspecific, polyclonal human immunoglobulin in the detection of focal inflammation by scintigraphy: Comparison with gallium-67 citrate and technetium-99m-labeled albumin

    International Nuclear Information System (INIS)

    Rubin, R.H.; Fischman, A.J.; Needleman, M.; Wilkinson, R.; Callahan, R.J.; Khaw, B.A.; Hansen, W.P.; Kramer, P.B.; Strauss, H.W.

    1989-01-01

    The accumulation of nonspecific polyclonal human immunoglobulin (IgG) radiolabeled with 125 I or 111 In was compared to that of [ 67 Ga]citrate and [ 99m Tc]albumin in rats with deep thigh inflammation due to Escherichia coli infection. Serial scintigrams were acquired at 1, 3, 24, and in some cases, 48 hr after injection. As early as 3 hr postinjection, [ 111 In]IgG showed greater accumulation at the lesion than [ 99m Tc]HSA (p less than 0.01). Both [ 125 I]IgG and [ 111 In]IgG showed greater accumulation than [ 67 Ga]citrate (p less than 0.01). At 24 hr, IgG image definition increased, while HSA image definition decreased, and the intensity of accumulation of both IgG preparations was greater than that of [ 67 Ga]citrate or [ 99m Tc]HSA (p less than 0.01). At all imaging times, [ 67 Ga]citrate accumulation was surprisingly low. In inflammation produced by Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Candida albicans, or turpentine, [ 111 In]IgG accumulation was similar to the results obtained with Escherichia coli. These studies suggest that focal sites of inflammation can be detected with radiolabeled nonspecific human polyclonal IgG

  5. Polyclonal and monoclonal antibodies specific for the six-helix bundle of the human respiratory syncytial virus fusion glycoprotein as probes of the protein post-fusion conformation

    Energy Technology Data Exchange (ETDEWEB)

    Palomo, Concepción; Mas, Vicente; Vázquez, Mónica; Cano, Olga [Unidad de Biología Viral, Centro Nacional de Microbiología, Madrid (Spain); CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain); Luque, Daniel; Terrón, María C. [Unidad de Microscopía Electrónica y Confocal, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain); Calder, Lesley J. [National Institute for Medical Research, MRC, Mill Hill, London NW7 1AA (United Kingdom); Melero, José A., E-mail: jmelero@isciii.es [Unidad de Biología Viral, Centro Nacional de Microbiología, Madrid (Spain); CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain)

    2014-07-15

    Human respiratory syncytial virus (hRSV) has two major surface glycoproteins (G and F) anchored in the lipid envelope. Membrane fusion promoted by hRSV{sub F} occurs via refolding from a pre-fusion form to a highly stable post-fusion state involving large conformational changes of the F trimer. One of these changes results in assembly of two heptad repeat sequences (HRA and HRB) into a six-helix bundle (6HB) motif. To assist in distinguishing pre- and post-fusion conformations of hRSV{sub F}, we have prepared polyclonal (α-6HB) and monoclonal (R145) rabbit antibodies specific for the 6HB. Among other applications, these antibodies were used to explore the requirements of 6HB formation by isolated protein segments or peptides and by truncated mutants of the F protein. Site-directed mutagenesis and electron microscopy located the R145 epitope in the post-fusion hRSV{sub F} at a site distantly located from previously mapped epitopes, extending the repertoire of antibodies that can decorate the F molecule. - Highlights: • Antibodies specific for post-fusion respiratory syncytial virus fusion protein are described. • Polyclonal antibodies were obtained in rabbit inoculated with chimeric heptad repeats. • Antibody binding required assembly of a six-helix bundle in the post-fusion protein. • A monoclonal antibody with similar structural requirements is also described. • Binding of this antibody to the post-fusion protein was visualized by electron microscopy.

  6. Effect of low doses of ionizing radiation on the thymus-dependent humoral immune response and the polyclonal activation of B-lymphocytes

    International Nuclear Information System (INIS)

    Sharetskij, A.N.; Surinov, B.P.; Abramova, M.R.

    2000-01-01

    The results of studies on the effect of the low-dose (10 cGy with the dose rate of 1cGy/min) γ-radiation on the indices of the mice system and local immune response are presented. The sheep erythrocytes were used as a thymus-dependent antigen. It is shown that the total irradiation with the above dose rate induced the increase in the primary thymus-dependent humoral immune response on the sheep erythrocytes and polyclonal activation of the B-lymphocytes. The sharp oppression of the antibody formation was observed in the immune response dynamics after the phase of the radiation-induced elevation. The injection of hydroquinone right after the irradiation resulted in elimination of the radiation stimulation of the polyclonal response of the B-cells. The essential decrease in the immunoantilogarithmic radiation effect took place in the animals treated with thymogen. The possible negative consequences of the low-dose ionizing radiation impact on the body immune system are discussed [ru

  7. Phenolics, Antiradical Assay and Cytotoxicity of Processed Mango ...

    African Journals Online (AJOL)

    Phenolics, Antiradical Assay and Cytotoxicity of Processed Mango ( Mangifera indica ) and Bush Mango ( Irvingia gabonensis ) Kernels. ... Nigerian Food Journal ... Phenolic constituents (total phenols, flavonoids, tannins, and anthocyanins), comparative antiradical potency and cytotoxicity of processed mango (Mangifera ...

  8. A cytotoxic serine proteinase isolated from mouse submandibular gland.

    Science.gov (United States)

    Shimamura, T; Nagumo, N; Ikigai, H; Murakami, K; Okubo, S; Toda, M; Ohnishi, R; Tomita, M

    1989-08-01

    We have isolated a novel cytotoxic factor from the submandibular glands of male BALB/c mice by Sephadex G-50 gel filtration chromatography and reverse-phase HPLC. The cytotoxic factor is a serine proteinase, which belongs to the mouse glandular kallikrein (mGK) family, with an Mr of approximately 27,000. The purified serine proteinase showed cytotoxic activity against mouse thymocytes in a dose-dependent manner, and a serine proteinase inhibitor, diisopropyl fluorophosphate, blocked its cytotoxic activity.

  9. Cytotoxic effect of betulinic acid and betulinic acid acetate isolated ...

    African Journals Online (AJOL)

    Cytotoxic effect of betulinic acid and betulinic acid acetate isolated from Melaleuca cajuput on human myeloid leukemia (HL-60) cell line. ... The cytotoxic effect of betulinic acid (BA), isolated from Melaleuca cajuput a Malaysian plant and its four synthetic derivatives were tested for their cytotoxicity in various cell line or ...

  10. Polyclonal Recipient nTregs Are Superior to Donor or Third-Party Tregs in the Induction of Transplantation Tolerance

    Directory of Open Access Journals (Sweden)

    Nina Pilat

    2015-01-01

    Full Text Available Induction of donor-specific tolerance is still considered as the “Holy Grail” in transplantation medicine. The mixed chimerism approach is virtually the only tolerance approach that was successfully translated into the clinical setting. We have previously reported successful induction of chimerism and tolerance using cell therapy with recipient T regulatory cells (Tregs to avoid cytotoxic recipient treatment. Treg therapy is limited by the availability of cells as large-scale expansion is time-consuming and associated with the risk of contamination with effector cells. Using a costimulation-blockade based bone marrow (BM transplantation (BMT model with Treg therapy instead of cytoreductive recipient treatment we aimed to determine the most potent Treg population for clinical translation. Here we show that CD4+CD25+ in vitro activated nTregs are superior to TGFβ induced iTregs in promoting the induction of chimerism and tolerance. Therapy with nTregs (but not iTregs led to multilineage chimerism and donor-specific tolerance in mice receiving as few as 0.5 × 106 cells. Moreover, we show that only recipient Tregs, but not donor or third-party Tregs, had a beneficial effect on BM engraftment at the tested doses. Thus, recipient-type nTregs significantly improve chimerism and tolerance and might be the most potent Treg population for translation into the clinical setting.

  11. Cytotoxic constituents of ethyl acetate fraction from Dianthus superbus.

    Science.gov (United States)

    Ding, Chengli; Zhang, Wu; Li, Jie; Lei, Jiachuan; Yu, Jianqing

    2013-01-01

    The ethyl acetate fraction (EE-DS) from Dianthus superbus was found to possess the cytotoxic activity against cancer cells in previous study. To investigate cytotoxic constituents, the bioassay-guided isolation of compounds from EE-DS was performed. Two dianthramides (1 and 2), three flavonoids (3-5), two coumarins (6 and 7) and three other compounds (8-10) were obtained. Structures of isolated compounds were identified by spectroscopic analysis. Cytotoxicity of the compounds against HepG2 cells was evaluated. Compound 1 showed the strongest cytotoxicity, compounds 10, 4, 3 and 5 had moderate cytotoxicity.

  12. Cytotoxicity of Poly(Alkyl Cyanoacrylate Nanoparticles

    Directory of Open Access Journals (Sweden)

    Einar Sulheim

    2017-11-01

    Full Text Available Although nanotoxicology has become a large research field, assessment of cytotoxicity is often reduced to analysis of one cell line only. Cytotoxicity of nanoparticles is complex and should, preferentially, be evaluated in several cell lines with different methods and on multiple nanoparticle batches. Here we report the toxicity of poly(alkyl cyanoacrylate nanoparticles in 12 different cell lines after synthesizing and analyzing 19 different nanoparticle batches and report that large variations were obtained when using different cell lines or various toxicity assays. Surprisingly, we found that nanoparticles with intermediate degradation rates were less toxic than particles that were degraded faster or more slowly in a cell-free system. The toxicity did not vary significantly with either the three different combinations of polyethylene glycol surfactants or with particle size (range 100–200 nm. No acute pro- or anti-inflammatory activity on cells in whole blood was observed.

  13. Improved cytotoxicity testing of magnesium materials

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Janine [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Department for Structural Research on Macromolecules, Max-Planck Str. 1, D - 21502 Geesthacht (Germany); Proefrock, Daniel [Helmholtz-Zentrum Geesthacht, Institute for Coastal Research, Department for Marine Bioanalytical Chemistry, Max-Planck Str. 1, D - 21502 Geesthacht (Germany); Hort, Norbert [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Department for Magnesium Processing, Max-Planck Str. 1, D - 21502 Geesthacht (Germany); Willumeit, Regine; Feyerabend, Frank [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Department for Structural Research on Macromolecules, Max-Planck Str. 1, D - 21502 Geesthacht (Germany)

    2011-06-25

    Metallic magnesium (Mg) and its alloys are highly suitable for medical applications as biocompatible and biodegradable implant materials. Magnesium has mechanical properties similar to bone, stimulates bone regeneration, is an essential non-toxic element for the human body and degrades completely within the body environment. In consequence, magnesium is a promising candidate as implant material for orthopaedic applications. Protocols using the guideline of current ISO standards should be carefully evaluated when applying them for the characterization of the cytotoxic potential of degradable magnesium materials. For as-cast material we recommend using 10 times more extraction medium than recommended by the ISO standards to obtain reasonable results for reliable cytotoxicity rankings of degradable materials in vitro. In addition primary isolated human osteoblasts or mesenchymal stem cells should be used to test magnesium materials.

  14. Improved cytotoxicity testing of magnesium materials

    International Nuclear Information System (INIS)

    Fischer, Janine; Proefrock, Daniel; Hort, Norbert; Willumeit, Regine; Feyerabend, Frank

    2011-01-01

    Metallic magnesium (Mg) and its alloys are highly suitable for medical applications as biocompatible and biodegradable implant materials. Magnesium has mechanical properties similar to bone, stimulates bone regeneration, is an essential non-toxic element for the human body and degrades completely within the body environment. In consequence, magnesium is a promising candidate as implant material for orthopaedic applications. Protocols using the guideline of current ISO standards should be carefully evaluated when applying them for the characterization of the cytotoxic potential of degradable magnesium materials. For as-cast material we recommend using 10 times more extraction medium than recommended by the ISO standards to obtain reasonable results for reliable cytotoxicity rankings of degradable materials in vitro. In addition primary isolated human osteoblasts or mesenchymal stem cells should be used to test magnesium materials.

  15. Study of Cytotoxic Effects of Benzonitrile Pesticides

    OpenAIRE

    Lovecka, Petra; Thimova, Marketa; Grznarova, Petra; Lipov, Jan; Knejzlik, Zdenek; Stiborova, Hana; Nindhia, Tjokorda Gde Tirta; Demnerova, Katerina; Ruml, Tomas

    2015-01-01

    The benzonitrile herbicides bromoxynil, chloroxynil, dichlobenil, and ioxynil have been used actively worldwide to control weeds in agriculture since 1970s. Even though dichlobenil is prohibited in EU since 2008, studies addressing the fate of benzonitrile herbicides in the environment show that some metabolites of these herbicides are very persistent. We tested the cytotoxic effects of benzonitrile herbicides and their microbial metabolites using two human cell lines, Hep G2 and HEK293T, rep...

  16. Cytotoxic triterpenoid saponins from Clematis tangutica.

    Science.gov (United States)

    Zhao, Min; Da-Wa, Zhuo-Ma; Guo, Da-Le; Fang, Dong-Mei; Chen, Xiao-Zhen; Xu, Hong-Xi; Gu, Yu-Cheng; Xia, Bing; Chen, Lei; Ding, Li-Sheng; Zhou, Yan

    2016-10-01

    Eight previously undescribed oleanane-type triterpenoid saponins, clematangoticosides A-H, together with eight known saponins, were isolated from the whole plants of Clematis tangutica (Maxim.) Korsh. Their structures were elucidated by extensive spectroscopic analysis, in combination with chemical methods (acid hydrolysis and mild alkaline hydrolysis). Clematangoticosides D-G were found to be unusual 23, 28-bidesmosidic glycosides. The cytotoxic activities of all of the isolated saponins were evaluated against the four human cancer cell lines SGC-7901, HepG2, HL-60 and U251MG. Clematoside S, sapindoside B, kalopanax saponin A, and koelreuteria saponin A exhibited cytotoxicity against all of the test cancer cell lines with IC50 values in the range of 1.88-27.20 μM, while clematangoticoside D and F showed selective cytotoxicity against SGC-7901 with IC50 values of 24.22 and 21.35 μM, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Cytotoxic and phytotoxic actions of Heliotropium strigosum.

    Science.gov (United States)

    Shah, Syed Majid; Hussain, Sajid; Khan, Arif-Ullah; Shah, Azhar-Ul-Haq Ali; Khan, Haroon; Ullah, Farhat; Barkatullah

    2015-05-01

    This study describes the cytotoxic and phytotoxic activities of the crude extract of Heliotropium strigosum and its resultant fractions. In brine shrimp toxicology assays, profound cytotoxicity was displayed by ethyl acetate (LD50 8.3 μg/ml) and chloroform (LD50 8.8 μg/ml) fractions, followed by relatively weak crude methanolic extract of H. strigosum (LD50 909 μg/ml) and n-hexane fraction (LD50 1000 μg/ml). In case of phytotoxicity activity against Lemna acquinoctialis, highest phytotoxic effect was showed by ethyl acetate fraction (LD50 91.0 μg/ml), while chloroform fraction, plant crude extract and n-hexane, respectively, caused 50%, 30.76 ± 1.1% and 30.7 ± 1.1% inhibitory action at maximum concentration used, that is, 1000 μg/ml. These data indicates that H. strigosum exhibits cytotoxic and phytotoxic potential, which explore its use as anticancer and herbicidal medicine. The ethyl acetate and chloroform fractions were more potent for the evaluated toxicity effects, thus recommended for isolation and identification of the active compounds. © The Author(s) 2012.

  18. Cytotoxic constituents of Soymida febrifuga from Myanmar.

    Science.gov (United States)

    Awale, Suresh; Miyamoto, Tatsuya; Linn, Thein Zaw; Li, Feng; Win, Nwet Nwet; Tezuka, Yasuhiro; Esumi, Hiroyasu; Kadota, Shigetoshi

    2009-09-01

    The 70% ethanol extract of Soymida febrifuga was found to kill PANC-1 human pancreatic cancer cells preferentially under nutrition-deprived conditions at a concentration of 10 microg/mL. Phytochemical investigation led to the isolation of 27 compounds including four new compounds [(3R)-6,4'-dihydroxy-8-methoxyhomoisoflavan (1), (2R)-7,4'-dihydroxy-5-methoxy-8-methylflavan (2), 7-hydroxy-6-methoxy-3-(4'-hydroxybenzyl)coumarin (3), and 6-hydroxy-7-methoxy-3-(4'-hydroxybenzyl)coumarin (4)]. 2',4'-Dihydroxychalcone (8) displayed the most potent preferential cytotoxicity (PC(50) 19.0 microM) against PANC-1 cells. In addition, the cytotoxic activity against colon 26-L5 carcinoma (colon 26-L5), B16-BL6 melanoma (B16-BL6), lung A549 adenocarcinoma (A549), cervix HeLa adenocarcinoma (HeLa), and HT-1080 fibrosarcoma (HT-1080) cell lines and their structure-activity relationship are discussed. The cytotoxic activity of 4'-hydroxy-3,5-dimethoxystilbene (6) against colon 26-L5 (IC(50) 2.96 microM) was found to be stronger than the positive control, doxorubicin, at IC(50) 3.12 microM.

  19. Production of anti-fullerene C{sub 60} polyclonal antibodies and study of their interaction with a conjugated form of fullerene

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, O. D., E-mail: odhendrick@gmail.com; Fedyunina, N. S. [Russian Academy of Sciences, Institute of Biochemistry (Russian Federation); Martianov, A. A. [Moscow State University (Russian Federation); Zherdev, A. V.; Dzantiev, B. B. [Russian Academy of Sciences, Institute of Biochemistry (Russian Federation)

    2011-09-15

    The aim of this study was to produce anti-fullerene C{sub 60} antibodies for the development of detection systems for fullerene C{sub 60} derivatives. To produce anti-fullerene C{sub 60} antibodies, conjugates of the fullerene C{sub 60} carboxylic derivative with thyroglobulin, soybean trypsin inhibitor, and bovine serum albumin were synthesized by carbodiimide activation and characterized. Immunization of rabbits by the conjugates led to the production of polyclonal anti-fullerene antibodies. The specificity of the immune response to fullerene was investigated. Indirect competitive immunoenzyme assay was developed for the determination of conjugated fullerene with detection limits of 0.04 ng/mL (calculated for coupled C{sub 60}) and 0.4 ng/mL (accordingly to total fullerene-protein concentration).

  20. Polyclonal immunoglobulins from a chronic hepatitis C virus patient protect human liver-chimeric mice from infection with a homologous hepatitis C virus strain

    DEFF Research Database (Denmark)

    Vanwolleghem, Thomas; Bukh, Jens; Meuleman, Philip

    2008-01-01

    The role of the humoral immune response in the natural course of hepatitis C virus (HCV) infection is widely debated. Most chronically infected patients have immunoglobulin G (IgG) antibodies capable of neutralizing HCV pseudoparticles (HCVpp) in vitro. It is, however, not clear whether these Ig...... were loaded with chronic phase polyclonal IgG and challenged 3 days later with a 100% infectious dose of the acute phase H77C virus, both originating from patient H. Passive immunization induced sterilizing immunity in five of eight challenged animals. In the three nonprotected animals, the HCV...... infection was attenuated, as evidenced by altered viral kinetics in comparison with five control IgG-treated animals. Plasma samples obtained from the mice at viral challenge neutralized H77C-HCVpp at dilutions as high as 1/400. Infection was completely prevented when, before administration to naïve...

  1. Epstein-Barr Virus Lytic Reactivation Activates B Cells Polyclonally and Induces Activation-Induced Cytidine Deaminase Expression: A Mechanism Underlying Autoimmunity and Its Contribution to Graves' Disease.

    Science.gov (United States)

    Nagata, Keiko; Kumata, Keisuke; Nakayama, Yuji; Satoh, Yukio; Sugihara, Hirotsugu; Hara, Sayuri; Matsushita, Michiko; Kuwamoto, Satoshi; Kato, Masako; Murakami, Ichiro; Hayashi, Kazuhiko

    2017-04-01

    Graves' disease is an autoimmune disease that results in and is the most common cause of hyperthyroidism, and the reactivation of persisting Epstein-Barr virus (EBV) in B lymphocytes induces the differentiation of host B cells into plasma cells. We previously reported that some EBV-infected B cells had thyrotropin receptor antibodies (TRAbs) as surface immunoglobulins (Igs), and EBV reactivation induced these TRAb+EBV+ cells to produce TRAbs. EBV reactivation induces Ig production from host B cells. The purpose of the present study was to examine total Ig productions from B cell culture fluids and to detect activation-induced cytidine deaminase (AID), nuclear factor kappa B (NF-κB), and EBV latent membrane protein (LMP) 1 in culture B cells during EBV reactivation induction and then we discussed the mechanisms of EBV reactivation-induced Ig production in relation to autoimmunity. We showed that the EBV reactivation induces the production of every isotype of Ig and suggested that the Ig production was catalyzed by AID through LMP1 and NF-κB. The results that the amount of IgM was significantly larger compared with IgG suggested the polyclonal B cell activation due to LMP1. We proposed the pathway of EBV reactivation induced Ig production; B cells newly infected with EBV are activated by polyclonal B cell activation and produce Igs through plasma cell differentiation induced by EBV reactivation. LMP1-induced AID enabled B cells to undergo class-switch recombination to produce every isotype of Ig. According to this mechanism, EBV rescues autoreactive B cells to produce autoantibodies, which contribute to the development and exacerbation of autoimmune diseases.

  2. Evaluation of the inflammatory activity in chronic osteomyelitis. Contribution of the scintigraphy with polyclonal antibodies; Avaliacao de atividade inflamatoria em osteomielite cronica. Contribuicao da cintilografia com anticorpos policlonais

    Energy Technology Data Exchange (ETDEWEB)

    Sapienza, Marcelo Tatit

    1996-07-01

    Active chronic osteomyelitis or complicating osteomyelitis (superimposed on diseases that changes the normal bone structure fractures, post-surgery, prosthesis) can be difficult to diagnose by anatomic radiological imaging modalities, like plain radiograph and CT. These diseases frequently cause also increased bone remodeling, leading to nonspecific uptake of Tc-99m-bone scan agents and gallium-67. New radiopharmaceuticals with greater inflammation/infection avidity and specificity are being developed, including the nonspecific polyclonal immunoglobulin (IgG) labeled with technetium-99. Tc-99m-IgG may be available as a ready to use kit, with no reported side effects, low patient absorbed radiation dose and low cost. The mechanism of IgG uptake at the inflammation site has not been fully elucidated yet. Specific (receptor linking, physico-chemical immunoglobulin properties) and nonspecific mechanisms (enhanced vascular permeability and macromolecular exudate) has been suggested. IgG scintigraphy results are affected by the isotope, labeling procedure adopted and characteristics of the inflammatory focus. Nineteen patients with suspected osteomyelitis (active chronic osteomyelitis or violated bone osteomyelitis) were studied by Tc-99m-IgG scintigraphy (directly labeled polyclonal immunoglobulin, Sandoglobuilina - Sandoz). All patients also underwent standard three-phase bone scintigraphy using methylene diphosphonate (Tc-99m-MDP), gallium-67 scintigraphy and plain radiographs. Infection was found in 8 sites. Sensitivity and specificity for Tc-99m-MDP, gallium-67 and Tc 99m-IgG scintigraphy were, respectively, 88 and 36%, 75 and 73%,88 and 82%. All patients with false positive IgG scintigraphies had previous surgery. Other current scintigraphic procedures used in the diagnosis of osteomyelitis are also reviewed. (author)

  3. Production of polyclonal antibody against Tehran strain influenza virus (A/H1N1/2009 hemagglutinin conserved domain (HA2: brief report

    Directory of Open Access Journals (Sweden)

    Somayeh Zamani

    2015-10-01

    Full Text Available Background: The influenza virus is one of the most important factors for higher morbidity and mortality in the world. Recently, researchers have been focused on influenza conserved antigenic proteins such as hemagglutinin stalk domain (HA2 for vaccine production and serological studies. The HA2 plays a major role in the fusion of the virus with host cells membrane. The immunity system enables to produce antibody against HA2. The aim of this study is polyclonal antibody production against influenza HA2. Methods: This study was done in the Influenza Research Lab, Pasteur Institute of Iran, Tehran for one year from September 2013 to October 2014. In the present study, recombinant HA2 protein was produced in prokaryotic system and purified using Nickel affinity chromatography. The purified HA2 was mixed with Freund’s adjuvant (complete and incomplete and injected into two New Zealand white rabbits by intramuscularly and subcutaneously routes. Immunization was continued for several months with two weeks interval. Before each immunization, blood was drawn by venous puncture from the rabbit ear. Function of rabbit's sera was evaluated using radial immunodiffusion (RID in both forms, Single RID (SRID and Double RID (DRID. Finally, antiserum activity against HA2 was evaluated using western blotting as serological assay. Results: Sedimentary line and zone was observed in RID assays (SRID and DRID represent interaction between HA2 protein and anti- HA2 antibody. As well as, western blotting results was positive for HA2 protein. Therefore, these results showed that polyclonal antibody produced against HA2 protein can identify HA2 protein antigenic sites. Conclusion: These findings show that humoral immune responses have properly been stimulated in rabbits and these antibodies can identify HA2 protein and may be suitable for other serological methods.

  4. Generation of TCR-Expressing Innate Lymphoid-like Helper Cells that Induce Cytotoxic T Cell-Mediated Anti-leukemic Cell Response.

    Science.gov (United States)

    Ueda, Norihiro; Uemura, Yasushi; Zhang, Rong; Kitayama, Shuichi; Iriguchi, Shoichi; Kawai, Yohei; Yasui, Yutaka; Tatsumi, Minako; Ueda, Tatsuki; Liu, Tian-Yi; Mizoro, Yasutaka; Okada, Chihiro; Watanabe, Akira; Nakanishi, Mahito; Senju, Satoru; Nishimura, Yasuharu; Kuzushima, Kiyotaka; Kiyoi, Hitoshi; Naoe, Tomoki; Kaneko, Shin

    2018-06-05

    CD4 + T helper (Th) cell activation is essential for inducing cytotoxic T lymphocyte (CTL) responses against malignancy. We reprogrammed a Th clone specific for chronic myelogenous leukemia (CML)-derived b3a2 peptide to pluripotency and re-differentiated the cells into original TCR-expressing T-lineage cells (iPS-T cells) with gene expression patterns resembling those of group 1 innate lymphoid cells. CD4 gene transduction into iPS-T cells enhanced b3a2 peptide-specific responses via b3a2 peptide-specific TCR. iPS-T cells upregulated CD40 ligand (CD40L) expression in response to interleukin-2 and interleukin-15. In the presence of Wilms tumor 1 (WT1) peptide, antigen-specific dendritic cells (DCs) conditioned by CD4-modified CD40L high iPS-T cells stimulated WT1-specific CTL priming, which eliminated WT1 peptide-expressing CML cells in vitro and in vivo. Thus, CD4 modification of CD40L high iPS-T cells generates innate lymphoid helper-like cells inducing bcr-abl-specific TCR signaling that mediates effectiveanti-leukemic CTL responses via DC maturation, showing potential for adjuvant immunotherapy against leukemia. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Bacterial CpG-DNA activates dendritic cells in vivo: T helper cell-independent cytotoxic T cell responses to soluble proteins.

    Science.gov (United States)

    Sparwasser, T; Vabulas, R M; Villmow, B; Lipford, G B; Wagner, H

    2000-12-01

    Receptors for conserved molecular patterns associated with microbial pathogens induce synthesis of co-stimulatory molecules and cytokines in immature dendritic cells (DC), as do antigen-reactive CD4 T helper cells via CD40 signaling. Once activated, antigen-presenting DC may activate CD8 T cell responses in a T helper cell-independent fashion. Using immunostimulatory CpG-oligonucleotides (ODN) mimicking bacterial CpG-DNA, we tested whether CpG-DNA bypasses the need for T helper cells in CTL responses towards proteins by directly activating antigen-presenting DC to transit into professional APC. We describe that immature DC in situ constitutively process soluble proteins and generate CD8 T cell determinants yet CD8 T cell responses remain abortive. Induction of primary antigen-specific CD8 cytotoxic T lymphocyte (CTL)-mediated responses becomes initiated in wild-type as well as T helper cell-deficient mice, provided soluble protein and CpG-ODN are draining into the same lymph node. Specifically we show that CpG-ODN trigger antigen-presenting immature DC within the draining lymph node to acutely up-regulate co-stimulatory molecules and produce IL-12. These results provide new insights for generating in vivo efficient CTL responses to soluble proteins which may influence vaccination strategies.

  6. Cytotoxic and radioprotective effects of Podophyllum hexandrum.

    Science.gov (United States)

    Shukla, Sandeep Kumar; Chaudhary, Pankaj; Prem Kumar, Indracanti; Afrin, Farhat; Puri, Satish Chandra; Qazi, Ghulam Nabi; Sharma, Rakesh Kumar

    2006-07-01

    Podophyllum hexandrum, a herb thriving in Himalayas has already been reported to exhibit antitumor and radioprotective properties. Present study was undertaken to unravel the possible mechanism responsible for the cytotoxic and radioprotective properties of REC-2001, a fraction isolated from the rhizome of P. hexandrum using murine peritoneal macrophages and plasmid DNA as model systems. Cell death, levels of intracellular reactive oxygen species (ROS) and apoptosis were studied employing trypan blue exclusion assay, dichlorofluorescein diacetate and DNA fragmentation assay, respectively. Superoxide anions, hydroxyl radicals and DNA damage were estimated following nitroblue tetrazolium, 2-deoxyribose degradation and plasmid DNA relaxation assays, respectively. Pre-irradiation administration of REC-2001 to peritoneal macrophages in the concentration range of 25-200μg/ml significantly reduced radiation induced ROS generation, DNA damage, apoptosis and cell killing in comparison to radiation control group indicating radioprotective potential. Studies with plasmid DNA indicated the ability of REC-2001 to inhibit 20Gy induced single and double strand breaks further supporting the antioxidative potential. However, REC-2001 in a dose-dependent fashion induced cell death, ROS and DNA fragmentation indicating the cytotoxic nature. REC-2001, in presence of 100μM copper sulfate, generated significant amount of hydroxyl radicals and superoxide anions indicating ability to act as a pro-oxidant in presence of metal ions. The superoxide anion generation was found to be sensitive to metal chelators like EDTA and deferoxamine mesylate (DFR). These results suggest that the ability of REC-2001 to act as a pro-oxidant in presence of metal ions and antioxidant in presence of free radicals might be responsible for cytotoxic and radioprotective properties.

  7. Flavonoids of Calligonum polygonoides and their cytotoxicity.

    Science.gov (United States)

    Ahmed, Hayam; Moawad, Abeer; Owis, Asmaa; AbouZid, Sameh; Ahmed, Osama

    2016-10-01

    Context Calligonum polygonoides L. subsp. comosum L' Hér. (Polygonaceae), locally known as "arta", is a slow-growing small leafless desert shrub. Objective Isolation, structure elucidation and evaluation of cytotoxic activity of flavonoids from C. polygonoides aerial parts. Materials and methods Flavonoids in the hydroalcoholic extract of the of C. polygonoides were isolated and purified using column chromatography and preparative HPLC. The structures of the isolated flavonoids were elucidated on the basis of spectroscopic data including 2D NMR techniques. The cytotoxic activity of the isolated flavonoids (6.25, 25, 50 and 100 μg/mL) was evaluated against liver HepG2 and breast MCF-7 cancer cell lines using sulphorhodamine-B assay. Results A new flavonoid, kaempferol-3-O-β-D-(6″-n-butyl glucuronide) (1), and 13 known flavonoids, quercetin 3-O-β-D-(6″-n-butyl glucuronide) (2), kaempferol-3-O-β-D-(6″-methyl glucuronide) (3), quercetin-3-O-β-D-(6″-methyl glucuronide) (4), quercetin-3-O-glucuronide (5), kaempferol-3-O-glucuronide (6), quercetin-3-O-α-rhamnopyranoside (7), astragalin (8), quercetin-3-O-glucopyranoside (9), taxifolin (10), (+)-catechin (11), dehydrodicatechin A (12), quercetin (13), and kaempferol (14), were isolated from the aerial parts of C. polygonoides. Quercetin showed significant cytotoxic activity against HepG2 and MCF-7 cell lines with IC50 values of 4.88 and 0.87 μg/mL, respectively. Structure-activity relationships were analyzed by comparing IC50 values of several pairs of flavonoids differing in one structural element. Discussion and conclusion The activity against breast cancer cell lines decreased by glycosylation at C-3. The presence of 2,3-double bond in ring C, carbonyl group at C-4 and 3',4'-dihydroxy substituents in ring B are essential structural requirements for the cytotoxic activity against breast cancer cells.

  8. A potent cytotoxic photoactivated platinum complex

    Czech Academy of Sciences Publication Activity Database

    Mackay, F.S.; Woods, J.A.; Heringová, Pavla; Kašpárková, Jana; Pizarro, A.M.; Moggach, S.A.; Parsons, S.; Brabec, Viktor; Sadler, P.J.

    2007-01-01

    Roč. 104, č. 52 (2007), s. 20743-20748 ISSN 0027-8424 R&D Projects: GA ČR(CZ) GA305/05/2030; GA ČR(CZ) GD204/03/H016; GA MZd(CZ) NR8562; GA AV ČR(CZ) 1QS500040581 Grant - others:GA AV ČR(CZ) KAN200200651 Program:KA Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : cytotoxicity * DNA binding * photochemistry Subject RIV: BO - Biophysics Impact factor: 9.598, year: 2007

  9. Characteristics of medication errors with parenteral cytotoxic drugs

    OpenAIRE

    Fyhr, A; Akselsson, R

    2012-01-01

    Errors involving cytotoxic drugs have the potential of being fatal and should therefore be prevented. The objective of this article is to identify the characteristics of medication errors involving parenteral cytotoxic drugs in Sweden. A total of 60 cases reported to the national error reporting systems from 1996 to 2008 were reviewed. Classification was made to identify cytotoxic drugs involved, type of error, where the error occurred, error detection mechanism, and consequences for the pati...

  10. Cytotoxicity and genotoxicity of biogenic silver nanoparticles

    International Nuclear Information System (INIS)

    Lima, R; Feitosa, L O; Ballottin, D; Tasic, L; Durán, N; Marcato, P D

    2013-01-01

    Biogenic silver nanoparticles with 40.3 ± 3.5 nm size and negative surface charge (− 40 mV) were prepared with Fusarium oxysporum. The cytotoxicity of 3T3 cell and human lymphocyte were studied by a TaliTM image-based cytometer and the genotoxicity through Allium cepa and comet assay. The results of BioAg-w (washed) and BioAg-nw (unwashed) biogenic silver nanoparticles showed cytotoxicity exceeding 50 μg/mL with no significant differences of response in 5 and 10 μg/mL regarding viability. Results of genotoxicity at concentrations 5.0 and 10.0 ug/mL show some response, but at concentrations 0.5 and 1.0 μg/mL the washed and unwashed silver nanoparticles did not present any effect. This in an important result since in tests with different bacteria species and strains, including resistant, MIC (minimal inhibitory concentration) had good answers at concentrations less than 1.9 μg/mL. This work concludes that biogenic silver nanoparticles may be a promising option for antimicrobial use in the range where no cyto or genotoxic effect were observed. Furthermore, human cells were found to have a greater resistance to the toxic effects of silver nanoparticles in comparison with other cells.

  11. Study of Cytotoxic Effects of Benzonitrile Pesticides

    Science.gov (United States)

    Lovecka, Petra; Thimova, Marketa; Grznarova, Petra; Lipov, Jan; Knejzlik, Zdenek; Stiborova, Hana; Nindhia, Tjokorda Gde Tirta; Demnerova, Katerina; Ruml, Tomas

    2015-01-01

    The benzonitrile herbicides bromoxynil, chloroxynil, dichlobenil, and ioxynil have been used actively worldwide to control weeds in agriculture since 1970s. Even though dichlobenil is prohibited in EU since 2008, studies addressing the fate of benzonitrile herbicides in the environment show that some metabolites of these herbicides are very persistent. We tested the cytotoxic effects of benzonitrile herbicides and their microbial metabolites using two human cell lines, Hep G2 and HEK293T, representing liver and kidneys as potential target organs in humans. The cell viability and proliferation were determined by MTT test and RTCA DP Analyzer system, respectively. The latter allows real-time monitoring of the effect of added substances. As the cytotoxic compounds could compromise cell membrane integrity, the lactate dehydrogenase test was performed as well. We observed high toxic effects of bromoxynil, chloroxynil, and ioxynil on both tested cell lines. In contrast, we determined only low inhibition of cell growth in presence of dichlobenil and microbial metabolites originating from the tested herbicides. PMID:26339609

  12. Cytotoxic isoferulic acidamide from Myricaria germanica (Tamaricaceae).

    Science.gov (United States)

    Nawwar, Mahmoud A; Swilam, Noha F; Hashim, Amani N; Al-Abd, Ahmed M; Abdel-Naim, Ashraf B; Lindequist, Ulrike

    2013-01-01

    Tamgermanitin, a unique N-trans-Isoferuloyltyramine, together with the hitherto unknown polyphenolics, 2,4-di-O-galloyl-(α/β)-glucopyranose and kaempferide 3,7-disulphate have been isolated from the leaf aqueous ethanol extract of the false tamarisk, Myricaria germanica DESV. In addition, 18 known phenolics were also separated and characterized. All structures were elucidated on the basis of detailed analysis of 1D- (1)H and (13)C NMR, COSY, HSQC, HMBC and HRFTESIMS spectral data. The extract, its chromatographic column fractions and the isolated isoferuloyltyramine, tamgermanetin demonstrated potential cytotoxic effect against three different tumor cell lines, namely liver (Huh-7), breast (MCF-7) and prostate (PC-3). The IC 50''s were found to be substantially low with low-resistance possibility. DNA flow-cytometic analysis indicated that column fractions and tamgermanetin enhanced pre-G apoptotic fraction. Both materials showed inhibiting activity against PARP enzyme activity. In conclusion, we report the isolation and identification of a novel compound, tamgermanitin, from the aqueous ethanol extract of Myricaria germanica leaves. Further, different fractions of the extract and tamgermanitin exhibit potent cytotoxic activities which warrant further investigations.

  13. Cytotoxicity study of plant Aloe vera (Linn

    Directory of Open Access Journals (Sweden)

    Atul N Chandu

    2012-01-01

    Full Text Available Background: The objective of this study has been to evaluate the in-vitro antitumor activity of Aloe vera extract of in cultured B16F10 melanoma cell line by measuring cell viability using "Trypan blue exclusion assay" method. Aim: To find out such kind of anticancer drug which is a cheap, safe, less toxic, and more potent drug compared to chemotherapy drug. Materials and Methods: In-vitro antitumor activity cell culture1, drug treatment (standard and test extract and Trypan blue exclusion assay growth and viability test 1 were used. Treatment of Aloe vera extract against B16F10 melanoma cell line, in all concentration range, showed decrease in percent cell viability, as compared to that of negative when examined by "Trypan blue exclusion assay". Results: In overall variation of test samples, Aloe vera extract showed its best activity in the concentration of 300 μg/ml, which was approximately equal to the activity of standard drug doxorubicin. Evaluation of in-vitro antitumor activity revealed that Aloe vera extract exhibits good cytotoxic activity. The best cytotoxic activity by Aloe vera was shown at 200 μg/ml concentration. Conclusion: The study of cytoprotection against normal cells by micronucleus assay has shown that the herbal extracts have less toxic effects to the normal blood lymphocytes, as compared to that of standard anticancer drug.

  14. Spectratyping analysis of the islet-reactive T cell repertoire in diabetic NOD Igμnull mice after polyclonal B cell reconstitution

    Directory of Open Access Journals (Sweden)

    Sercarz Eli E

    2011-07-01

    Full Text Available Abstract Background Non Obese Diabetic mice lacking B cells (NOD.Igμnull mice do not develop diabetes despite their susceptible background. Upon reconstitution of B cells using a chimera approach, animals start developing diabetes at 20 weeks of age. Methods We have used the spectratyping technique to follow the T cell receptor (TCR V beta repertoire of NOD.Igμnull mice following B cell reconstitution. This technique provides an unbiased approach to understand the kinetics of TCR expansion. We have also analyzed the TCR repertoire of reconstituted animals receiving cyclophosphamide treatment and following tissue transplants to identify common aggressive clonotypes. Results We found that B cell reconstitution of NOD.Igμnull mice induces a polyclonal TCR repertoire in the pancreas 10 weeks later, gradually diversifying to encompass most BV families. Interestingly, these clonotypic BV expansions are mainly confined to the pancreas and are absent from pancreatic lymph nodes or spleens. Cyclophosphamide-induced diabetes at 10 weeks post-B cell reconstitution reorganized the predominant TCR repertoires by removing potential regulatory clonotypes (BV1, BV8 and BV11 and increasing the frequency of others (BV4, BV5S2, BV9, BV16-20. These same clonotypes are more frequently present in neonatal pancreatic transplants under the kidney capsule of B-cell reconstituted diabetic NOD.Igμnull mice, suggesting their higher invasiveness. Phenotypic analysis of the pancreas-infiltrating lymphocytes during diabetes onset in B cell reconstituted animals show a predominance of CD19+ B cells with a B:T lymphocyte ratio of 4:1. In contrast, in other lymphoid organs (pancreatic lymph nodes and spleens analyzed by FACS, the B:T ratio was 1:1. Lymphocytes infiltrating the pancreas secrete large amounts of IL-6 and are of Th1 phenotype after CD3-CD28 stimulation in vitro. Conclusions Diabetes in NOD.Igμnull mice appears to be caused by a polyclonal repertoire of T cell

  15. [Research on medical speciality of traditional Chinese medicines using dot-immunoblotting method based on polyclonal antibody prepared from traditional Chinese medicines with hot/cold nature].

    Science.gov (United States)

    Wang, Houwei; Dou, Yanling; Tian, Jingzhen; Li, Feng; Wang, Shijun; Wang, Zhenguo

    2009-02-01

    To research on the substantial foundation of the medical speciality of Chinese traditional medicines from immunogenicity. Control antigen with hot nature was prepared from the mixture of the aqueous extracts of three Chinese traditional medicines with three typical hot nature of Alpinia officinarum, Cinnamomum cassia and Curculigo orchioides, while that with cold nature prepared with Rheum palmatum, Anemarrhena asphodeloides, Coptis chinensis, and polyclonal antibody was prepared by immunizing rabbit with control antigen. Dot blotting was performed between the polyclonal antibody of control antigen and the aqueous extracts of nine Chinese traditional medicines on a piece of PVDF membrane, and the blotting signals were analyzed by the software of Quantity One. Blotting signals with hot control antigen of nine Chinese traditional medicines in descending were Zingiber officinale, Aconitum carmichaeli, Eucommia ulmoides, Fraxinus rhynchophylla, Lonicera japonica, Anemarrhena asphodeloides, Coptis chinensis, Rheum palmatum and Phellodendron chinense, which degree of similarity to control antigen in peak value were 57.33%, 43.56 %, 34.16%, 30.2%, 28.81%, 26.53%, 21.68%, 17.62% and 14.85%, respectively. Blotting signals with cold control antigen were Rheum palmatum, Anemarrhena asphodeloides, Coptis chinensis, Phellodendron chinense, Zingiber officinale, Lonicera japonica, Fraxinus rhynchophylla, Eucommia ulmoides and Aconitum carmichaeli in descending, of which degree of similarity to cold control antigen in peak value were 55.22%, 54.23%, 46.72%, 34.08%, 30.3%, 24.48%, 24.33%, 20.35% and 15.17%, respectively. Results of cluster analysis with Wistar's method showed that nine medicines were classified into two groups, one group included Phellodendron chinense, Anemarrhena asphodeloides, Coptis chinensis, Rheum palmatum, another was Zingiber officinale, Aconitum carmichaeli, Eucommia ulmoides, Fraxinus rhynchophylla, Lonicera japonica. Blotting signals of nine medicines

  16. In-Vivo Neutralization of Botulinum Neurotoxin Serotype E Using Rabbit Polyclonal Antibody Developed against BoNT/E Light Chain.

    Science.gov (United States)

    Rani, Sarita; Ponmariappan, S; Sharma, Arti; Kamboj, D V; Jain, A K

    2017-01-01

    Clostridium botulinum is an obligate anaerobic, Gram positive bacterium that secretes extremely toxic substances known as botulinum neurotoxins (BoNTs) that cause serious paralytic illness called botulism. Based upon the serological properties, these neurotoxin have been classified into seven serotypes designated from A to G. Due to extreme toxicity of BoNTs, these neurotoxins have been designated as category A biowarfare agents. There is no commercial neutralizing antibody available for the treatment of botulism. Hence there is an urgent need to develop therapeutic intervention for prevention and cure of botulism within short period. BoNT antiserum injection is still the effective treatment. In the present study, the recombinant light chain of BoNT/E was successfully purified in soluble form. The purified rBoNT/E LC was used for the generation of polyclonal antibody in rabbit. In order to find out the neutralizing capacity of generated antisera, rabbit antiserum was incubated with 20 LD50 of botulinum neurotoxin type E for 1 hour at 37°C and then injected intraperitoneally (IP) into mice. Further in another set of experiments antiserum was administered in different ways that included administration of - antiserum and BoNT/E toxin simultaneously without preincubation, one after another at the same and different time points for its therapeutic ability. To find out cross neutralization capacity, rBoNT/E LC antiserum was pre-incubated with 5 LD50 of BoNT/A, BoNT/B, BoNT/F and then injected (IP) into mice. In all the cases mice were observed continuously for 96 hours. The results clearly indicate that developed polyclonal rabbit antiserum showed serotype specific neutralization of BoNT/E toxin only but not of BoNT/A, BoNT/B and BoNT/F. The developed antibodies will be used for preventive and therapeutic intervention of type 'E' botulism. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Effect of varying incubation periods on cytotoxicity and virucidal ...

    African Journals Online (AJOL)

    Backgrounds: Justicia gendarussa Burm.f. has an anti-HIV activity. This study was conducted to evaluate the effects of incubation periods on the cytotoxicity and virucidal activities of the J. gendarussa leaves extract on MOLT-4 cells. Materials and Methods: The cytotoxicity assay was evaluated by using the WST-1 test with ...

  18. Cytotoxicity of Sambucus ebulus on cancer cell lines and protective ...

    African Journals Online (AJOL)

    Regarding the traditional utilization of Sambucus ebulus, Iranian native botany and its active ingredients (e.g. ebulitin and ebulin 1), cytotoxicity of ethyl acetate ... cytotoxic agent on liver and colon cancer cells and suggest that vitamins C and E may protect normal cells, when SEE were used in cancer therapy in future.

  19. CYTOTOXICITY AND MUTAGENESIS METHODS FOR EVALUATING TOXICITY REMOVAL FROM WASTEWATERS

    Science.gov (United States)

    This project was a feasibility study of the effectiveness of a mammalian cell cytotoxicity assay and a mammalian cell mutagenesis assay for monitoring the toxicity and mutagenicity of influent and effluent wastewater at treatment plants. In the cytotoxicity assay, ambient samples...

  20. Cytotoxic activity of Agave lechuguilla Torr | Casillas | African ...

    African Journals Online (AJOL)

    The cytotoxic activity of extract and isolated saponin from leaves of Agave lechuguilla was investigated. Ethanol extract from leaves of A. lechuguilla exhibited cytotoxic activity against HeLa cells in vitro (50% inhibitory concentration (IC50) = 89 μg/ml). Bioassay-guided fractionation of this extract had led to the isolation of 5-β ...

  1. Cytotoxic compounds from the leaves of Combretum paniculatum Vent

    African Journals Online (AJOL)

    It is used locally in the treatment of carcinomous tumors. The cytotoxic activity of pheophorbide a and pheophorbide a-methyl ester isolated from the leaves of C. paniculatum were investigated. In vitro cytotoxicity of the compounds were evaluated against HT-29, MCF-7 and HeLa cancer cell lines using the methyl thiazolyl ...

  2. Antibacterial and Cytotoxic Activities of Acacia nilotica Lam ...

    African Journals Online (AJOL)

    Erah

    that had maximum bactericidal activity against all the tested isolates, but showed < 30 % host cell cytotoxicity. Conclusion: The lysate of Acacia nilotica ... cytotoxic effects on human cells. EXPERIMENTAL. Plant material. Acacia nilotica Lam .... a detergent that permeabilizes eukaryotic cells and results in HBMEC damage.

  3. induced acute cytotoxicity in human cervical epithelial carcinoma cells

    African Journals Online (AJOL)

    Molecular basis of arsenite (As +3 )-induced acute cytotoxicity in human cervical epithelial carcinoma cells. ... Libyan Journal of Medicine ... Methods: After performing cytotoxic assays on a human epithelial carcinoma cell line, expression analysis was done by quantitative polymerase chain reaction, western blotting, and ...

  4. Anti-inflammatory and cytotoxic activities of five Veronica species.

    Science.gov (United States)

    Harput, U Sebnem; Saracoglu, Iclal; Inoue, Makoto; Ogihara, Yukio

    2002-04-01

    Biological activities of five Veronica species (Scrophulariaceae), V. cymbalaria, V. hederifolia, V. pectinata var. glandulosa, V. persica and V. polita were studied for their anti-inflammatory and cytotoxic activities. Their methanol extracts showed both the inhibitory activity of nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophages and cytotoxic activity against KB epidermoid carcinoma and B16 melanoma. When the methanol extracts were fractionated between water and chloroform, water fractions significantly inhibited NO production without any cytotoxicity, while chloroform fractions showed cytotoxicity dose-dependently. When the radical scavenging activity was determined using 2,2-diphenyl-1-picryl-hydrazyl (DPPH), water fractions of the five Veronica species scavenged free radicals effectively, suggesting that the inhibitory effect of this species on NO production was due to their radical scavenging activity. On the other hand, chloroform fractions of Veronica species except for V. cymbalaria showed similar cytotoxic activity against KB and B16 melanoma cells.

  5. Development of a polyclonal anti-dugong immunoglobulin G (IgG) antibody with evaluation of total plasma IgG in a living dugong (Dugong dugon) population.

    Science.gov (United States)

    Wong, Arthur; Lanyon, Janet M; McKee, Sara J; Linedale, Richard; Woolford, Lucy; Long, Trevor; Leggatt, Graham R

    2018-06-01

    Species-specific antibodies (Ab) for the measurement of immunoglobulins (Ig) are valuable tools for determining the humoral immune status of threatened and endangered wildlife species such as dugongs. However, no studies have reported antibody reagents against dugong immunoglobulin. The object of this study was to develop an Ab with specificity for dugong IgG and apply this tool to survey total IgG levels in plasma samples from a live wild population of dugongs in southern Queensland, Australia. Dugong IgG was isolated from plasma by protein A/G column chromatography and a polyclonal antiserum was successfully raised against the dugong IgG through immunization of mice. The anti-dugong antiserum was reactive with dugong serum but not immunoglobulin from other species such as rats and humans. When tested against a panel of dugong plasma samples, relative IgG levels from dugongs (n = 116) showed biologically relevant relationships with pregnancy status and a principal component of Body Mass Index (BMI)/globulin/fecal glucocorticosteroid (chronic stress) levels combined, which together accounted for 9.2% of the variation in total Ig levels. Together these data suggest that dugongs show variation in total IgG and that this correlates with some physiological parameters of dugong health. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. A convenient model of severe, high incidence autoimmune gastritis caused by polyclonal effector T cells and without perturbation of regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Eric Tu

    Full Text Available Autoimmune gastritis results from the breakdown of T cell tolerance to the gastric H(+/K(+ ATPase. The gastric H(+/K(+ ATPase is responsible for the acidification of gastric juice and consists of an α subunit (H/Kα and a β subunit (H/Kβ. Here we show that CD4(+ T cells from H/Kα-deficient mice (H/Kα(-/- are highly pathogenic and autoimmune gastritis can be induced in sublethally irradiated wildtype mice by adoptive transfer of unfractionated CD4(+ T cells from H/Kα(-/- mice. All recipient mice consistently developed the most severe form of autoimmune gastritis 8 weeks after the transfer, featuring hypertrophy of the gastric mucosa, complete depletion of the parietal and zymogenic cells, and presence of autoantibodies to H(+/K(+ ATPase in the serum. Furthermore, we demonstrated that the disease significantly affected stomach weight and stomach pH of recipient mice. Depletion of parietal cells in this disease model required the presence of both H/Kα and H/Kβ since transfer of H/Kα(-/- CD4(+ T cells did not result in depletion of parietal cells in H/Kα(-/- or H/Kβ(-/- recipient mice. The consistency of disease severity, the use of polyclonal T cells and a specific T cell response to the gastric autoantigen make this an ideal disease model for the study of many aspects of organ-specific autoimmunity including prevention and treatment of the disease.

  7. Passive immunization with a polyclonal antiserum to the hemoglobin receptor of Haemophilus ducreyi confers protection against a homologous challenge in the experimental swine model of chancroid.

    Science.gov (United States)

    Leduc, Isabelle; Fusco, William G; Choudhary, Neelima; Routh, Patty A; Cholon, Deborah M; Hobbs, Marcia M; Almond, Glen W; Orndorff, Paul E; Elkins, Christopher

    2011-08-01

    Haemophilus ducreyi, the etiologic agent of chancroid, has an obligate requirement for heme. Heme is acquired by H. ducreyi from its human host via TonB-dependent transporters expressed at its bacterial surface. Of 3 TonB-dependent transporters encoded in the genome of H. ducreyi, only the hemoglobin receptor, HgbA, is required to establish infection during the early stages of the experimental human model of chancroid. Active immunization with a native preparation of HgbA (nHgbA) confers complete protection in the experimental swine model of chancroid, using either Freund's or monophosphoryl lipid A as adjuvants. To determine if transfer of anti-nHgbA serum is sufficient to confer protection, a passive immunization experiment using pooled nHgbA antiserum was conducted in the experimental swine model of chancroid. Pigs receiving this pooled nHgbA antiserum were protected from a homologous, but not a heterologous, challenge. Passively transferred polyclonal antibodies elicited to nHgbA bound the surface of H. ducreyi and partially blocked hemoglobin binding by nHgbA, but were not bactericidal. Taken together, these data suggest that the humoral immune response to the HgbA vaccine is protective against an H. ducreyi infection, possibly by preventing acquisition of the essential nutrient heme.

  8. Passive Immunization with a Polyclonal Antiserum to the Hemoglobin Receptor of Haemophilus ducreyi Confers Protection against a Homologous Challenge in the Experimental Swine Model of Chancroid▿

    Science.gov (United States)

    Leduc, Isabelle; Fusco, William G.; Choudhary, Neelima; Routh, Patty A.; Cholon, Deborah M.; Hobbs, Marcia M.; Almond, Glen W.; Orndorff, Paul E.; Elkins, Christopher

    2011-01-01

    Haemophilus ducreyi, the etiologic agent of chancroid, has an obligate requirement for heme. Heme is acquired by H. ducreyi from its human host via TonB-dependent transporters expressed at its bacterial surface. Of 3 TonB-dependent transporters encoded in the genome of H. ducreyi, only the hemoglobin receptor, HgbA, is required to establish infection during the early stages of the experimental human model of chancroid. Active immunization with a native preparation of HgbA (nHgbA) confers complete protection in the experimental swine model of chancroid, using either Freund's or monophosphoryl lipid A as adjuvants. To determine if transfer of anti-nHgbA serum is sufficient to confer protection, a passive immunization experiment using pooled nHgbA antiserum was conducted in the experimental swine model of chancroid. Pigs receiving this pooled nHgbA antiserum were protected from a homologous, but not a heterologous, challenge. Passively transferred polyclonal antibodies elicited to nHgbA bound the surface of H. ducreyi and partially blocked hemoglobin binding by nHgbA, but were not bactericidal. Taken together, these data suggest that the humoral immune response to the HgbA vaccine is protective against an H. ducreyi infection, possibly by preventing acquisition of the essential nutrient heme. PMID:21646451

  9. [Levels and molecular heterogeneity of serotonin transporter protein in platelets of patients with different mental diseases: a comparative analysis with the use of monoclonal and polyclonal antibodies].

    Science.gov (United States)

    Brusov, O S; Faktor, M I; Zlobina, G P; Bologov, P V; Kaleda, V G; Oleĭchik, I V; Korenev, A N; Piatnitskiĭ, A N; Dupin, A M; Katasonov, A B; Morozova, M A; Beniashvili, A G; Lozier, R Kh; Pavlova, E V; Segal, O L; Massino, Iu S; Dmitriev, A D

    2001-01-01

    Polyclonal (PAb) and monoclonal (MAb) antibodies to CT2-epitope of the C-terminal fragment of serotonin transporter (SERT) protein were used to study the levels and molecular heterogeneity of platelet SERT in healthy donors and patients with affective (AD) and somatoform (SD) disorders, schizoaffective disorder (SAD) and schizophrenia. SERT was found to exist as high molecular wight (HMW) and low molecular weight (LMW) forms separated after electrophoresis. The levels of HMW and LMW forms of SERT were significantly, decreased in mentally ill patients as compared to healthy individuals. Unlike PAb, horse radish peroxidase (HRP)-conjugated MAbs were more sensitive and specific to SERT and could detect the LMW form of SERT as a duplet protein form with MW about 40 and 43 kDa. The MAb to CT2 C-terminal fragment of SERT conjugated with HRP is considered to be a new valuable tool for further investigation of SERT expression, properties, and posttranslation modification in the controls and in patients with different psychopathology.

  10. Control of polyclonal immunoglobulin production from human lymphocytes by leukotrienes; leukotriene B4 induces an OKT8(+), radiosensitive suppressor cell from resting, human OKT8(-) T cells

    International Nuclear Information System (INIS)

    Atluru, D.; Goodwin, J.S.

    1984-01-01

    We report that leukotriene B4 (LTB4), a 5-lipoxygenase metabolite of arachidonic acid, is a potent suppressor of polyclonal Ig production in pokeweed mitogen (PWM)-stimulated cultures of human peripheral blood lymphocytes, while LTC4 and LTD4 have little activity in this system. Preincubation of T cells with LTB4 in nanomolar to picomolar concentrations rendered these cells suppressive of Ig production in subsequent PWM-stimulated cultures of fresh, autologous B + T cells. This LTB4-induced suppressor cell was radiosensitive, and its generation could be blocked by cyclohexamide but not by mitomycin C. The LTB4-induced suppressor cell was OKT8(+), while the precursor for the cell could be OKT8(-). The incubation of OKT8(-) T cells with LTB4 for 18 h resulted in the appearance of the OKT8(+) on 10-20% of the cells, and this could be blocked by cyclohexamide but not by mitomycin C. Thus, LTB4 in very low concentrations induces a radiosensitive OKT8(+) suppressor cell from OKT8(-) cells. In this regard, LTB4 is three to six orders of magnitude more potent than any endogenous hormonal inducer of suppressor cells previously described. Glucocorticosteroids, which block suppressor cell induction in many systems, may act by inhibiting endogenous production of LTB4

  11. Iodoacetyl-functionalized pullulan: A supplemental enhancer for single-domain antibody-polyclonal antibody sandwich enzyme-linked immunosorbent assay for detection of survivin.

    Science.gov (United States)

    Matsushita, Takahiko; Arai, Hidenao; Koyama, Tetsuo; Hatano, Ken; Nemoto, Naoto; Matsuoka, Koji

    2017-11-01

    Survivin, an inhibitor of the apoptosis protein family, is a potent tumor marker for diagnosis and prognosis. The enzyme-linked immunosorbent assay (ELISA) is one of the methods that has been used for detection of survivin. However, ELISA has several disadvantages caused by the use of conventional antibodies, and we have therefore been trying to develop a novel ELISA system using camelid single-domain antibodies (VHHs) as advantageous replacements. Here we report a supplemental approach to improve the VHH-polyclonal antibody sandwich ELISA for survivin detection. Iodoacetyl-functionalized pullulan was synthesized, and its thiol reactivity was characterized by a model reaction with l-cysteine. The thiophilic pullulan was applied to an immunoassay asan additive upon coating of standard assay plates with an anti-survivin VHH fusion protein with C-terminal cysteine. The results showed that the mole ratio of the additive to VHH had a significant effect on the consequent response. Mole ratios of 0.07, 0.7, and 7 led to 90% lower, 15% higher, and 69% lower responses, respectively, than the response of a positive control in which no additive was used. The background levels observed in any additive conditions were as low as that of a negative control lacking both VHH and the additive. These results indicate the applicability of the thiol-reactive pullulan as a response enhancer to VHH-based ELISA. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Immune escape mutants of Highly Pathogenic Avian Influenza H5N1 selected using polyclonal sera: identification of key amino acids in the HA protein.

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    Ioannis Sitaras

    Full Text Available Evolution of Avian Influenza (AI viruses--especially of the Highly Pathogenic Avian Influenza (HPAI H5N1 subtype--is a major issue for the poultry industry. HPAI H5N1 epidemics are associated with huge economic losses and are sometimes connected to human morbidity and mortality. Vaccination (either as a preventive measure or as a means to control outbreaks is an approach that splits the scientific community, due to the risk of it being a potential driving force in HPAI evolution through the selection of mutants able to escape vaccination-induced immunity. It is therefore essential to study how mutations are selected due to immune pressure. To this effect, we performed an in vitro selection of mutants from HPAI A/turkey/Turkey/1/05 (H5N1, using immune pressure from homologous polyclonal sera. After 42 rounds of selection, we identified 5 amino acid substitutions in the Haemagglutinin (HA protein, most of which were located in areas of antigenic importance and suspected to be prone to selection pressure. We report that most of the mutations took place early in the selection process. Finally, our antigenic cartography studies showed that the antigenic distance between the selected isolates and their parent strain increased with passage number.

  13. Evaluation of 99Tcm nonspecific polyclonal IgG in the detection of rejection in a single lung transplant canine model

    International Nuclear Information System (INIS)

    Larcos, G.; McLarty, A.J.; McGregor, C.G.A.; Brown, M.L.; Hung, J.C.; O'Connor, M.K.; Tazelaar, H.D.

    1993-01-01

    Acute rejection is an important cause of graft failure in single lung transplantation, however, current noninvasive tests are neither sensitive nor specific for this diagnosis. The aim of this study was to determine whether 99 Tc m -labelled human nonspecific polyclonal IgG ( 99 Tc m -IgG) may serve as a marker for acute pulmonary rejection following allotransplantation in a dog model. Seventeen mongrel dogs were studied, including four controls and thirteen dogs which underwent surgery [right autotransplant recipient right unmodified allotransplant recipient, and right immunosuppressed allotransplant recipient]. At 6 days following surgery, all dogs received 67 Ga-citrate and 99 Tc m -IgG. Two days later all dogs were sacrified. Post-mortem examination revealed acute lung rejection in nine animals. No significant difference was found in the percentage uptake of both 99 Tc m -IgG and 67 Ga-citrate per gram of tissue between rejecting and nonrejecting transplanted lungs. In cases of moderate to severe rejection, only 67 Ga-citrate showed a significant difference in uptake between rejecting and contralateral native lungs, respectively. We conclude that 99 Tc m -IgG does not accurately identify acute lung rejection in the early postoperative period. (author)

  14. The future of cytotoxic therapy: selective cytotoxicity based on biology is the key

    International Nuclear Information System (INIS)

    Bono, Johann S de; Tolcher, Anthony W; Rowinsky, Eric K

    2003-01-01

    Although mortality from breast cancer is decreasing, 15% or more of all patients ultimately develop incurable metastatic disease. It is hoped that new classes of target-based cytotoxic therapeutics will significantly improve the outcome for these patients. Many of these novel agents have displayed cytotoxic activity in preclinical and clinical evaluations, with little toxicity. Such preferential cytotoxicity against malignant tissues will remain tantamount to the Holy Grail in oncologic therapeutics because this portends improved patient tolerance and overall quality of life, and the capacity to deliver combination therapy. Combinations of such rationally designed target-based therapies are likely to be increasingly important in treating patients with breast carcinoma. The anticancer efficacy of these agents will, however, remain dependent on the involvement of the targets of these agents in the biology of the individual patient's disease. Results of DNA microarray analyses have raised high hopes that the analyses of RNA expression levels can successfully predict patient prognosis, and indicate that the ability to rapidly 'fingerprint' the oncogenic profile of a patient's tumor is now possible. It is hoped that these studies will support the identification of the molecules driving a tumor's growth, and the selection of the appropriate combination of targeted agents in the near future

  15. Generation and characterization of polyclonal antibodies specific to N-terminal extension of p85 isoform of ribosomal protein S6 kinase 1 (p85 S6K1

    Directory of Open Access Journals (Sweden)

    Savinska L. O.

    2015-08-01

    Full Text Available Aim. Generation of polyclonal antibodies specific to the ribosomal protein S6 kinase isoform – p85S6K1 and directed to the N-terminal (1–23 aa extension of p85S6K1. Methods. Animal immunization with synthetic (1–23 aa peptide, ELISA, Western blot, Immunoprecipitation, immunofluorescent analysis. Results. Polyclonal antibodies have been generated, which specifically recognize only p85 but not p70 isoform of S6K1 in western blot, immunoprecipitation and immunofluorescence analysis. Conclusions. The obtained antibodies can be recommended for studies on the p85S6K1 and other S6K1 isoforms possessing the N-terminal extension – the identification of binding protein partners, analysis of subcellular localization under different physiological conditions, elucidation of the signal transduction pathways involving different S6K1 isoforms.

  16. Cytotoxicity of alginate for orthodontic use

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    Matheus Melo Pithon

    2012-12-01

    Full Text Available OBJECTIVE: To evaluate the cytotoxicity of three different alginate impression materials for orthodontic use. METHODS: Three different brands of alginate were divided into three groups, namely, Group JCO (Jeltrate Chromatic Ortho, OP (Orthoprint and CO (Cavex Orthotrace. Three control groups were also included: Group C+ (positive control, consisting of detergent Tween 80; Group C- (negative control, consisting of PBS, and Group CC (cell control, consisting of cells not exposed to any material. After manipulating the materials according to the respective manufacturer instructions, samples were made with the use of silicon rings. Then the samples were immersed in Eagle's minimum essential medium (MEM for 2 minutes. The supernatants were then removed and brought into direct contact with L929 fibroblasts. After exposure to the medium, the cells were incubated for 24 hours. Then 100 µl of 0.01% neutral red dye were added. The cells were incubated again for 3 hours so that the dye could be absorbed. After this 3-hour period, the cells were fixed to perform the viable cell count, using a spectrophotometer (BioTek, Winooski, Vermont, USA at a wavelength of 492 nm. RESULTS: Statistical differences were found when Groups CC and C- were compared with the other experimental groups. Group JCO had the highest cytotoxicity, followed by Groups OP and CO. CONCLUSION: Based on the results obtained in this work, it was concluded that all alginate impression materials are potentially cytotoxic.OBJETIVO: avaliar a citotoxicidade de três diferentes alginatos de uso ortodôntico. MÉTODOS: foram avaliados três diferentes alginatos divididos em três grupos, denominados grupo JCO (Jeltrate Chromatic Ortho, OP (Orthoprint e CO (Carrex Orthotrace. Três grupos controle também participaram: controle + (C+, constituído pelo detergente celular Tween 80; controle - (C- PBS; e controle de célula (CC onde as células não foram expostas a nenhum material. Após manipula

  17. Cytotoxicity and genotoxicity of lipid nanocapsules.

    Science.gov (United States)

    Le Roux, Gaël; Moche, Hélène; Nieto, Alejandro; Benoit, Jean-Pierre; Nesslany, Fabrice; Lagarce, Frédéric

    2017-06-01

    Lipid nanocapsules (LNCs) offer a promising method for the entrapment and nanovectorisation of lipophilic molecules. This new type of nanocarrier, formulated according to a solvent-free process and using only regulatory-approved components, exhibits many prerequisites for being well tolerated. Although toxicological reference values have already been obtained in mice, interaction of LNCs at the cell level needs to be elucidated. LNCs, measuring from 27.0±0.1nm (25nm LNCs) and 112.1±1.8nm (100nm LNCs) and with a zeta potential between -38.7±1.2mV and +9.18±0.4mV, were obtained by a phase inversion process followed by post-insertion of carboxy- or amino-DSPE-PEG. Trypan blue, MTS and neutral red uptake (NRU) assays were performed to evaluate the cytotoxicity of LNCs on mouse macrophage-like cells RAW264.7 after 24h of exposure. The determination of 50% lethal concentration (LC50) showed a size effect of LNCs on toxicity profiles: LC50 ranged from 1.036mg/L (MTS) and 0.477mg/mL (NRU) for 25nm LNCs, to 4.42mg/mL (MTS) and 2.18mg/mL (NRU) for 100nm LNCs. Surfactant Solutol® HS15 has been shown to be the only constituent to exhibit cytotoxicity; its LC50 reached 0.427mg/mL. Moreover, LNCs were not more toxic than their components in simple mixtures. At sublethal concentration, 100nm LNCs only were able to induce a significant production of nitric oxide (NO) by RAW264.7 cells, as assessed by the Griess reaction. Again, surfactant was the only component responsible for an increased NO release (1.8±0.2-fold). Genotoxicity assays revealed no DNA damage on human lymphocytes in both the in vitro Comet and micronucleus assays using 4-hour and 24-hour treatments, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Interleukin-2 activation of cytotoxic cells in postmastectomy seroma.

    Science.gov (United States)

    Gercel-Taylor, C; Hoffman, J P; Taylor, D D; Owens, K J; Eisenberg, B L

    1996-02-15

    Lymphocytes were isolated from breast seroma fluids and used to study the mechanism of activation of cytotoxic lymphocytes and possible role of immunological potentiation following surgery in breast cancer patients. Single or serial samples were obtained from patients who had undergone mastectomy or lumpectomy with axillary node dissection. Lymphocytes were activated with rIL-2 (interleukin-2) and their cytotoxic activity was studied against Daudi and K562 cells and against a breast tumor line (SKBr-3). All of the patients (21/21) responded to IL-2 stimulation by significant activation of cytotoxic activity. The unstimulated cytotoxic activity of these cells against NK targets was low with less than 10% specific release in cytotoxicity assays. In simultaneous experiments, autologous seroma fluid was included during activation of lymphocytes to study possible regulatory molecules that may be present. In 17/21 patients, the presence of their seroma fluid, during the activation period, enhanced or did not effect the cytotoxic potential of their lymphocytes; inhibition was observed when seroma fluids from 4/21 patients were included. Analysis of the cytotoxic population derived from combined IL-2 and seroma treatments indicates the presence of cells with increased expression of CD56, and CD2, as well as in some cases CD16 expression. Cytotoxic lymphocytes derived from IL-2 and seroma treatments appeared to be more effective killers. Modulation of CD2 expression with seroma alone appeared to result in the generation of this highly cytotoxic population. This study demonstrates the role of CD2 expression in the effectiveness of LAK cell killing and also potential benefit of an immunotherapeutic approach to the postoperative treatment of carcinoma of the breast.

  19. Acquired agranulocytosis with granulocyte specific cytotoxic autoantibody.

    Science.gov (United States)

    Blaschke, J; Goeken, N E; Thompson, J S; Dick, F R; Gingrich, R D

    1979-05-01

    Multiple infections and severe neutropenia were found in a previously healthy 29 year old man with no history of similar syndromes in the family, drug ingestion or exposure to environmental toxins. There was no evidence at the time of presentation of diseases previously associated with agranulocytosis (e.g., neoplasia, thyrotoxicosis, chronic infection, collagen-vascular disease or leukoagglutinating antibody). His serum contained a nonagglutinating, complement-dependent, cytotoxic antibody, however, reactive with peripheral blood granulocytes from 35 per cent of normal donors. The neutropenia was not affected by steroids but resolved promptly after splenectomy. Microscopic examination of the spleen revealed ingestion of polymorphonuclear leukocytes by splenic macrophages. Family studies indicated that the target antigen was non-HLA and that the antibody was not absorbed by lymphocytes or platelets. We conclude that the agranulocytosis was autoimmune in origin and suggest that similar myeloid-specific immune responses could influence granulocyte tranfusion and bone marrow transplantation by alloimmune "rejection" that would not be avoided by matching only for HLA specificities.

  20. Diuron-induced rat bladder epithelial cytotoxicity.

    Science.gov (United States)

    Da Rocha, Mitscheli S; Arnold, Lora L; Pennington, Karen L; Muirhead, David; Dodmane, Puttappa R; Anwar, Muhammad M; Battalora, Michael; De Camargo, João Lauro V; Cohen, Samuel M

    2012-12-01

    Diuron, a substituted urea herbicide, is carcinogenic to the rat urinary bladder at high dietary levels (2500 ppm). To further elucidate the mode of action, this study aimed to determine the time course and sequence of bladder cytotoxic and proliferative changes induced by diuron treatment of male Wistar rats. Rats were randomized into two groups (control and 2500 ppm diuron) and treated for 28 days. Ten rats from each group were terminated on each of study days 1, 3, 7, or 28. Scanning electron micro scopy (SEM) showed urothelial cell swelling beginning on day 1, and by day 28, showed extensive necrosis, exfoliation and piling up of cells suggestive of hyperplasia. No difference in the bromo deoxyuridine labeling index was detected. In a second experiment, rats were randomized into control and diuron-treated groups and treated for 7 days or 8 weeks. After 7 days, transmission electron microscopy showed cell degenerative changes and distention of the cytoplasm, organelles, and nuclei characteristic of cytolysis. This resulted in protrusion of the superficial cells into the lumen, corresponding to the cell swelling observed previously by SEM. After 8 weeks, bladders in the diuron-treated group showed an increased incidence of simple hyperplasia by light microscopy (6/10, p diuron exposure in rats.

  1. Genotoxic monitoring of nurses handling cytotoxic drugs

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    Anna Tompa

    2016-01-01

    Full Text Available Objective: Several biomarkers may be used to detect harmful exposure and individual susceptibility to cancer. Monitoring of biomarkers related to exposure may have a significant effect on early detection of cell transformation, thereby aiding the primary prevention of various chronic and malignant diseases. Nurses who handle cytotoxic drugs are exposed to carcinogenic agents, which have the potential to interrupt the cell cycle and to induce chromosomal aberrations. The presence of high chromosomal aberrations indicates the need for intervention even when exposure to these carcinogens is low. Methods: Nationally representative samples of 552 nurses were investigated by a follow-up monitoring system. The measured biomarkers were clinical laboratory routine tests, completed with genotoxicological (chromosome aberrations [CAs] and sister chromatid exchanges [SCEs] and immunotoxicological monitoring (ratio of lymphocyte subpopulations and lymphocyte activation markers measured on peripheral blood lymphocytes. Results were compared to the data of 140 healthy, age-matched controls. Results: In nurses exposed to cytostatics, we observed a significantly increased frequency of CAs and SCEs compared with those in the controls. Cytostatic drug exposure also manifested itself in an increased frequency of helper T lymphocytes. Genotoxicological and immunotoxicological changes, as well as negative health effects (i.e., iron deficiency, anemia, and thyroid diseases, increased among cytostatic exposed subjects. Conclusions: These results raised concerns about the protection of nursing staff from chemical carcinogens in the working environment.

  2. Copper Nanoparticle Induced Cytotoxicity to Nitrifying Bacteria ...

    Science.gov (United States)

    With the inclusion of engineered nanomaterials in industrial processes and consumer products, wastewater treatments plants (WWTPs) will serve as a major sink for these emerging contaminants. Previous research has demonstrated that nanomaterials are potentially toxic to microbial communities utilized in biological wastewater treatment (BWT). Copper-based nanoparticles (CuNPs) are of particular interest based on their increasing use in wood treatment, paints, household products, coatings, and byproducts of semiconductor manufacturing. A critical step in BWT is nutrient removal via denitrification. This study examined the potential toxicity of bare and polyvinylpyrrolidone (PVP) coated CuO, and Cu2O nanoparticles, as well as Cu ions to microbial communities responsible for nitrogen removal in BWT. Inhibition was inferred from changes to the specific oxygen uptake rate (sOUR) in the absence and presence of Cu ions and CuNPs. X-ray absorption fine structure spectroscopy, with Linear Combination Fitting (LCF), was utilized to track changes to Cu speciation throughout exposure. Results indicate that the dissolution of Cu ions from CuNPs drive microbial inhibition. The presence of a PVP coating on CuNPs has little effect on inhibition. LCF fitting of the biomass combined with metal partitioning analysis supports the current hypothesis that Cu-induced cytotoxicity is primarily caused by reactive oxygen species formed from ionic Cu in solution via catalytic reaction inter

  3. Cytotoxicity and ion release of alloy nanoparticles

    International Nuclear Information System (INIS)

    Hahn, Anne; Fuhlrott, Jutta; Loos, Anneke; Barcikowski, Stephan

    2012-01-01

    It is well-known that nanoparticles could cause toxic effects in cells. Alloy nanoparticles with yet unknown health risk may be released from cardiovascular implants made of Nickel–Titanium or Cobalt–Chromium due to abrasion or production failure. We show the bio-response of human primary endothelial and smooth muscle cells exposed to different concentrations of metal and alloy nanoparticles. Nanoparticles having primary particle sizes in the range of 5–250 nm were generated using laser ablation in three different solutions avoiding artificial chemical additives, and giving access to formulations containing nanoparticles only stabilized by biological ligands. Endothelial cells are found to be more sensitive to nanoparticle exposure than smooth muscle cells. Cobalt and Nickel nanoparticles caused the highest cytotoxicity. In contrast, Titanium, Nickel–Iron, and Nickel–Titanium nanoparticles had almost no influence on cells below a nanoparticle concentration of 10 μM. Nanoparticles in cysteine dissolved almost completely, whereas less ions are released when nanoparticles were stabilized in water or citrate solution. Nanoparticles stabilized by cysteine caused less inhibitory effects on cells suggesting cysteine to form metal complexes with bioactive ions in media.

  4. Cytotoxic activity of quassinoids from Eurycoma longifolia.

    Science.gov (United States)

    Miyake, Katsunori; Li, Feng; Tezuka, Yasuhiro; Awale, Suresh; Kadota, Shigetoshi

    2010-07-01

    Twenty-four quassinoids isolated from Eurycoma longifolia Jack were investigated for their cytotoxicity against a panel of four different cancer cell lines, which includes three murine cell lines [colon 26-L5 carcinoma (colon 26-L5), B16-BL6 melanoma (B16-BL6), Lewis lung carcinoma (LLC)] and a human lung A549 adenocarcinoma (A549) cell line. Among the tested compounds, eurycomalactone (9) displayed the most potent activity against all the tested cell lines; colon 26-L5 (IC50 = 0.70 microM), B16-BL6 (IC50 = 0.59 microM), LLC (IC50 = 0.78 microM), and A549 (IC50 = 0.73 microM). These activities were comparable to clinically used anticancer agent doxorubicin (colon 26-L5, IC50 = 0.76 microM; B16-BL6, IC50 = 0.86 microM; LLC, IC50 = 0.80 microM; A549, IC50 = 0.66 microM).

  5. Production of polyclonal antibodies for lectin from Anticarsia gemmatalis hemolymph Produção de anticorpos policlonais para lectina de hemolinfa de Anticarsia gemmatalis

    Directory of Open Access Journals (Sweden)

    Mario Augusto Ono

    2005-10-01

    Full Text Available The velvet bean caterpillar Anticarsia gemmatalis promotes extensive damage to soybean and is controlled frequently by chemical insecticides. Due to risks to human and animal health as well as the environment, new approaches were developed to A. gemmatalis control such as the bioinsectide Baculoviru anticarsia. The development of resistance in A. gemmatalis populations treated along several generations with B. anticarsia was reported under laboratory conditions. The insects show complex mechanisms against microorganism infection, such as the lectins, that work as recognition molecules. The aim of this work was to develop polyclonal antibodies to A. gemmatalis lectin. The lectin activity in A. gemmatalis caterpillar hemolymph was evaluated using erythrocytes from human, rabbit, mouse, sheep and cow. Only bovine erythrocytes were not agglutinated by lectin. The rabbit erythrocytes showed stronger reactivity (1:512. Therefore the polyclonal antibodies were raised in rabbit immunized with autologous erythrocytes sensitized with lectin. The antibody to lectin showed a titer of 1:8 in immunodiffusion test. In this study we described a simple method for antibody production against hemolymph lectin without expensive purification techniques. A lagarta de Anticarsia gemmatalis promove extensos danos na cultura da soja e seu controle é geralmente baseado na aplicação de inseticidas químicos. Devido aos riscos à saúde humana, animal e ao meio ambiente, métodos alternativos de controle tem sido desenvolvidos como o bioinseticida Baculovirus anticarsia. Há relatos de desenvolvimento de resistência em populações de A. gemmatalis submetidas, em laboratório, ao tratamento com baculovirus durante várias gerações. Os insetos apresentam mecanismos elaborados de proteção contra agentes infecciosos, como as lectinas, que atuam como moléculas de reconhecimento. Assim, o objetivo deste estudo foi desenvolver anticorpos policlonais para lectina de A

  6. Cross-reactivity of a polyclonal antibody against Chinemys reevesii vitellogenin with the vitellogenins of other turtle species: Chelydra serpentina , Macrochelys temminckii , and Pelodiscus sinensis.

    Science.gov (United States)

    Saka, Masahiro; Tada, Noriko; Kamata, Yoichi

    2008-09-01

    Vitellogenin (VTG), a yolk-precursor protein in oviparous vertebrates, is a useful biomarker for reproductive physiology and environmental estrogenic pollution. To examine interspecific applicability of an enzyme-linked immunosorbent assay (ELISA) for quantifying Chinemys reevesii VTG, we observed cross-reactivity between a polyclonal antibody against Chinemys reevesii VTG and the VTGs from other turtle species: Chelydra serpentina (Chelydridae), Macrochelys temminckii (Chelydridae), and Pelodiscus sinensis (Trionychidae), which are phylogenetically distant from Chinemys reevesii (Geoemydidae). The VTGs of the three species were induced by injecting estradiol 17beta into the turtles and purified by using the EDTA-MgCl(2) precipitation method. The purified VTG appeared as a 200-kDa protein in sodium dodecylsulfate polyacrylamide gel electrophoresis, indicating that the molecular mass of the VTGs of the three species was similar to that of Chinemys reevesii VTG. The purified VTGs were serially diluted (0.004-2 mug/ml) and applied to the ELISA. Although the VTGs of the two chelydrid turtles showed cross-reactivity in a concentration-dependent manner, the degree of cross-reactivity was only 22.8-41.2% (mean=30.0%) and 19.7-53.0% (mean=33.2%) for Chelydra serpentina VTG and Macrochelys temminckii VTG, respectively. The ELISA may therefore be theoretically applicable to measure relative levels of the VTGs of these two species, but the absolute concentration values may be inaccurate. Pelodiscus sinensis VTG showed almost no cross-reactivity (8.0-9.7%, mean=8.9%) at any concentration tested, thus indicating the inapplicability of the ELISA to quantify Pelodiscus sinensis VTG. There are thus limitations in extending the applicability of the ELISA across species, even within the order Testudines.

  7. A Convenient Model of Severe, High Incidence Autoimmune Gastritis Caused by Polyclonal Effector T Cells and without Perturbation of Regulatory T Cells

    Science.gov (United States)

    Tu, Eric; Ang, Desmond K. Y.; Hogan, Thea V.; Read, Simon; Chia, Cheryl P. Z.; Gleeson, Paul A.; van Driel, Ian R.

    2011-01-01

    Autoimmune gastritis results from the breakdown of T cell tolerance to the gastric H+/K+ ATPase. The gastric H+/K+ ATPase is responsible for the acidification of gastric juice and consists of an α subunit (H/Kα) and a β subunit (H/Kβ). Here we show that CD4+ T cells from H/Kα-deficient mice (H/Kα−/−) are highly pathogenic and autoimmune gastritis can be induced in sublethally irradiated wildtype mice by adoptive transfer of unfractionated CD4+ T cells from H/Kα−/− mice. All recipient mice consistently developed the most severe form of autoimmune gastritis 8 weeks after the transfer, featuring hypertrophy of the gastric mucosa, complete depletion of the parietal and zymogenic cells, and presence of autoantibodies to H+/K+ ATPase in the serum. Furthermore, we demonstrated that the disease significantly affected stomach weight and stomach pH of recipient mice. Depletion of parietal cells in this disease model required the presence of both H/Kα and H/Kβ since transfer of H/Kα−/− CD4+ T cells did not result in depletion of parietal cells in H/Kα−/− or H/Kβ−/− recipient mice. The consistency of disease severity, the use of polyclonal T cells and a specific T cell response to the gastric autoantigen make this an ideal disease model for the study of many aspects of organ-specific autoimmunity including prevention and treatment of the disease. PMID:22096532

  8. Generation of polyclonal antibody with high avidity to rosuvastatin and its use in development of highly sensitive ELISA for determination of rosuvastatin in plasma

    Directory of Open Access Journals (Sweden)

    Al-Malaq Hamoud A

    2011-07-01

    Full Text Available Abstract In this study, a polyclonal antibody with high avidity and specificity to the potent hypocholesterolaemic agent rosuvastatin (ROS has been prepared and used in the development of highly sensitive enzyme-linked immunosorbent assay (ELISA for determination of ROS in plasma. ROS was coupled to keyhole limpt hemocyanin (KLH and bovine serum albumin (BSA using carbodiimide reagent. ROS-KLH conjugate was used for immunization of female 8-weeks old New Zealand white rabbits. The immune response of the rabbits was monitored by direct ELISA using ROS-BSA immobilized onto microwell plates as a solid phase. The rabbit that showed the highest antibody titer and avidity to ROS was scarified and its sera were collected. The IgG fraction was isolated and purified by avidity chromatography on protein A column. The purified antibody showed high avidity to ROS; IC50 = 0.4 ng/ml. The specificity of the antibody for ROS was evaluated by indirect ELISA using various competitors from the ROS-structural analogues and the therapeutic agents used with ROS in a combination therapy. The proposed ELISA involved a competitive binding reaction between ROS, in plasma sample, and the immobilized ROS-BSA for the binding sites on a limited amount of the anti-ROS antibody. The bound anti-ROS antibody was quantified with horseradish peroxidase-labeled second anti-rabbit IgG antibody (HRP-IgG and 3,3',5,5'-tetramethylbenzidine (TMB as a substrate for the peroxidase enzyme. The concentration of ROS in the sample was quantified by its ability to inhibit the binding of the anti-ROS antibody to the immobilized ROS-BSA and subsequently the color intensity in the assay wells. The assay enabled the determination of ROS in plasma at concentrations as low as 40 pg/ml.

  9. A polyclonal antibody based immunoassay detects seven subtypes of Shiga toxin 2 produced by Escherichia coli in human and environmental samples.

    Directory of Open Access Journals (Sweden)

    Xiaohua He

    Full Text Available BACKGROUND: Shiga toxin-producing Escherichia coli (STEC are frequent causes of severe human diseases ranging from diarrhea to hemolytic uremic syndrome. The existing strategy for detection of STEC relies on the unique sorbitol-negative fermentation property of the O157 strains, the most commonly identified serotype has been E. coli O157. It is becoming increasingly evident, however, that numerous non-O157 STEC serotypes also cause outbreaks and severe illnesses. It is necessary to have new methods that are capable of detecting all STEC strains. METHODS AND FINDINGS: Here we describe the development of a sandwich ELISA assay for detecting both O157 and non-O157 STECs by incorporating a novel polyclonal antibody (pAb against Stx2. The newly established immunoassay was capable of detecting Stx2a spiked in environmental samples with a limit of detection between 10 and 100 pg/mL in soil and between 100 and 500 pg/mL in feces. When applied to 36 bacterial strains isolated from human and environmental samples, this assay detected Stx2 in all strains that were confirmed to be stx2-positive by real-time PCR, demonstrating a 100% sensitivity and specificity. CONCLUSIONS: The sandwich ELISA developed in this study will enable any competent laboratory to identify and characterize Stx2-producing O157 and non-O157 strains in human and environmental samples, resulting in rapid diagnosis and patient care. The results of epitope mapping from this study will be useful for further development of a peptide-based antibody and vaccine.

  10. In vitro Cytotoxic and Antioxidant Activity of Leaf Extracts of ...

    African Journals Online (AJOL)

    plant were tested for cytotoxicity against four cancer cells, viz, MCF-7 (oestrogen ... Results: The methanol extract showed the highest antioxidant activity (DPPH, half maximal inhibitory .... Total flavonoid content was determined using the.

  11. Cytotoxic diterpenoids from Jatropha curcas cv. nigroviensrugosus CY Yang Roots.

    Science.gov (United States)

    Liu, JieQing; Yang, YuanFeng; Xia, JianJun; Li, XuYang; Li, ZhongRong; Zhou, Lin; Qiu, MingHua

    2015-09-01

    An investigation of phytochemicals from the roots of Jatropha curcas cv. nigroviensrugosus resulted in the isolation of twenty diterpenoids, including lathyranlactone, an unusual diterpenoid lactone possessing a 5/13/3 tricyclic skeleton, jatrocurcasenones A-E and jatrophodiones B-E, as well as 10 known analogues. All isolates were evaluated for cytotoxicity against the HL-60, SMMC-772, A-549, MCF-7 and SW480 human tumor cell lines using the MTS viability assay. Four of the known analogues showed cytotoxic activity in these cell lines, with IC50 values ranging from 2.0 to 23.0 μM. Moreover, the assessment of their cytotoxic structure-activity relationships showed the epoxy ring between C-5 and C-6 and the hydroxyl group at C-2 were the key functionalities for cytotoxicity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Effect of Cytotoxicity of Pegylated Liposomal Recombinant Human ...

    African Journals Online (AJOL)

    drug release pattern were evaluated spectrophotometrically. The cytotoxicity effect of pegylated nanoliposomal ... encapsulating a broad range of drugs can be used as drug .... addition, PEG helps to increase pharmacokinetic properties and ...

  13. CD56 marks human dendritic cell subsets with cytotoxic potential

    NARCIS (Netherlands)

    Roothans, D.; Smits, E.; Lion, E.; Tel, J.; Anguille, S.

    2013-01-01

    Human plasmacytoid and myeloid dendritic cells (DCs), when appropriately stimulated, can express the archetypal natural killer (NK)-cell surface marker CD56. In addition to classical DC functions, CD56(+) DCs are endowed with an unconventional cytotoxic capacity.

  14. Cytotoxicity and Apoptotic Activity of Ficus pseudopalma Blanco ...

    African Journals Online (AJOL)

    Blanco Leaf Extracts Against Human Prostate Cancer Cell. Lines ... Keywords: Ficus pseudopalma, Cytotoxicity, Apopotic, human prostate PRST2 cancer cell, Lupeol,. Quercetin. ..... apoptosis through Fas-receptor mediated pathway in a ...

  15. Antimycobacterial and cytotoxic activities of extracts from fungal ...

    African Journals Online (AJOL)

    Antimycobacterial and cytotoxic activities of extracts from fungal isolates of Lake Magadi. Keno David Kowanga, Joan John Eliona Munissi, Rose Masalu, Stephen Samwel Nyandoro, Pax Masimba, Erastus Gatebe ...

  16. Phytochemical Analysis and Cytotoxicity Evaluation of Kelussia odoratissima Mozaff.

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    Amir Abbas Momtazi

    2017-06-01

    Conclusions: The present results suggest a direct cytotoxic activity of K. odoratissima leaf extract against human cancer cell lines. This activity of K. odoratissima may find application in combination with traditional herbal medicines to develop a new anticancer pharmacopuncture therapy.

  17. The Antifungal Activity and Cytotoxicity of Silver Containing Denture ...

    African Journals Online (AJOL)

    2015-10-30

    Oct 30, 2015 ... Objective: Denture base materials are susceptible to fungal adhesion, which is an important .... (Shimadzu Corp., Kyoto, Japan) to achieve a wavelength ..... assay for detection of cytotoxicity and prediction of acute toxicity.

  18. Effect of radiotherapy on lymphocyte cytotoxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, J; Melen, B [Central Microbiological Laboratory, Stockholm County Council (Sweden); Blomgren, H; Glas, U; Perlmann, P

    1975-11-01

    The cytotoxic functions of highly purified blood lymphocytes from patients with breast cancer were studied before and after radiotherapy. Addition of PHA or of rabbit antibodies to target cells (chicken erythrocytes) were chosen as two means of inducing lymphocyte cytotoxicity in vitro. The proportion of T and non-T lymphocytes was determined by means of E and EAC rosette tests. The antibody-induced cytotoxicity of lymphocytes decreased following radiotherapy while that mediated by PHA remained unchanged. There was some reduction in the percentage of EAC rosette-forming cells. These results, as well as earlier observations, suggest that the decrease in the peripheral blood of the proportion of lymphocytes with receptors for activated complement is responsible for changes in the antibody-mediated lymphocyte cytotoxicity.

  19. IN VITRO CYTOTOXICITY OF BTEX METABOLITES IN HELA CELL LINES

    Science.gov (United States)

    Fuel leakage from underground storage tanks is a major source of groundwater contamination. Although the toxicity of regulated compounds such as benzene, toluene, ethylbenzene, and xylene (BTEX) are well recognized, the cytotoxicity of their metabolites has not been studied exte...

  20. Leishmanicidal and cytotoxic activity of extracts and saponins from ...

    African Journals Online (AJOL)

    ISSN: 1596-5996 (print); 1596-9827 (electronic) ... Purpose: To evaluate the leishmanicidal and cytotoxic activity of alcohol and non-alcohol extracts and .... each) in a percolator at room temperature and ..... nitric oxide-dependent mechanism.

  1. Antibacterial and Cytotoxic Activities of Acacia nilotica Lam ...

    African Journals Online (AJOL)

    Erah

    Keywords: Acacia nilotica, ESBLs, MRSA, E. coli, Klebsiella, Antibacterial resistance, Cytotoxicity. Received: ... infectious diseases, is an age-long practice, especially ... used in a variety of infections. ... E. coli K1 [14] and MRSA [15] were used.

  2. Immunomodulatory, Cytotoxicity, and Antioxidant Activities of Roots of Ziziphus mauritiana

    OpenAIRE

    Afzal, Samina; Batool, Murium; Ch, Bashir Ahmad; Ahmad, Ashfaq; Uzair, Muhammad; Afzal, Khurram

    2017-01-01

    Aims: The study is conducted to evaluate the immunomodulatory, cytotoxicity, and antioxidant potential of Ziziphus mauritiana (Rhamnaceae). Phytochemical analysis of Z. mauritiana revealed the presence of alkaloids, anthraquinone glycoside, cardiac glycoside, saponin, tannin, and flavonoids. Methodology: The cytotoxicity of the plant Z. mauritiana was evaluated by brine shrimp lethality test. Antioxidant parameters such as superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and ma...

  3. Antimicrobial and Cytotoxic Assessment of Marine Cyanobacteria - Synechocystis and Synechococcus

    OpenAIRE

    Martins, Rosário F.; Ramos, Miguel F.; Herfindal, Lars; Sousa, José A.; Skærven, Kaja; Vasconcelos, Vitor M.

    2008-01-01

    Aqueous extracts and organic solvent extracts of isolated marine cyanobacteria strains were tested for antimicrobial activity against a fungus, Gram-positive and Gram-negative bacteria and for cytotoxic activity against primary rat hepatocytes and HL-60 cells. Antimicrobial activity was based on the agar diffusion assay. Cytotoxic activity was measured by apoptotic cell death scored by cell surface evaluation and nuclear morphology. A high percentage of apoptotic cells were observed for HL-60...

  4. Permeation of cytotoxic formulations through swatches from selected medical gloves.

    Science.gov (United States)

    Klein, Michael; Lambov, Nikolai; Samev, Nikola; Carstens, Gerhard

    2003-05-15

    The permeability of selected medical glove materials to various cytotoxic agents is described. Fifteen cytotoxic agents were prepared at the highest concentrations normally encountered by hospital personnel. Four single-layer and two double-layer glove systems made of two materials--latex and neoprene--were exposed to the drugs for 30, 60, 90, 120, 150, and 180 minutes. Circular sections of the glove material were cut from the cuff and evaluated without any pretreatment. Permeability tests were conducted in an apparatus consisting of a donor chamber containing the cytotoxic solution and a collection chamber filled with water (the acceptor medium). The two sections were separated by the glove material. Permeating portions, collected in water as the acceptor medium, were analyzed by either ultraviolet-visible light spectrophotometry or high-performance liquid chromatography (HPLC). Permeation rates were calculated on the basis of the concentration of the cytotoxic agent in the acceptor medium. Spectrophotometric measurements were taken every 30 minutes, and HPLC analysis was performed at the end of the three-hour period. Average permeation rates for 14 drugs were low (materials. All glove materials tested were impermeable to most of the cytotoxic agents over a period of three hours. Carmustine was the only agent that substantially permeated single-layer latex glove materials. Permeation of most tested cytotoxic formulations was low through swatches of material from various medical gloves.

  5. In Vitro Evidence of the Presence of Mesenchymal Stromal Cells in Cervical Cancer and Their Role in Protecting Cancer Cells from Cytotoxic T Cell Activity

    Science.gov (United States)

    Montesinos, Juan J.; Mora-García, María de L.; Mayani, Héctor; Flores-Figueroa, Eugenia; García-Rocha, Rosario; Fajardo-Orduña, Guadalupe R.; Castro-Manrreza, Marta E.; Weiss-Steider, Benny

    2013-01-01

    Mesenchymal stromal cells (MSCs) have been isolated from different tumors and it has been suggested that they support tumor growth through immunosuppression processes that favor tumor cell evasion from the immune system. To date, however, the presence of MSCs in cervical cancer (CeCa) and their possible role in tumor growth remains unknown. Herein we report on the presence of MSCs in cervical tissue, both in normal conditions (NCx-MSCs) and in CeCa (CeCa-MSCs), and described several biological properties of such cells. Our study showed similar patterns of cell surface antigen expression, but distinct differentiation potentials, when we compared both cervical MSC populations to MSCs from normal bone marrow (BM-MSCs, the gold standard). Interestingly, CeCa-MSCs were negative for the presence of human papiloma virus, indicating that these cells are not infected by such a viral agent. Also, interestingly, and in contrast to NCx-MSCs, CeCa-MSCs induced significant downregulation of surface HLA class I molecules (HLA-A*0201) on CaSki cells and other CeCa cell lines. We further observed that CeCa-MSCs inhibited antigen-specific T cell recognition of CaSki cells by cytotoxic T lymphocytes (CTLs). HLA class I downregulation on CeCa cells correlated with the production of IL-10 in cell cocultures. Importantly, this cytokine strongly suppressed recognition of CeCa cells by CTLs. In summary, this study demonstrates the presence of MSCs in CeCa and suggests that tumor-derived MSCs may provide immune protection to tumor cells by inducing downregulation of HLA class I molecules. This mechanism may have important implications in tumor growth. PMID:23656504

  6. Human Polyclonal Antibodies Produced through DNA Vaccination of Transchromosomal Cattle Provide Mice with Post-Exposure Protection against Lethal Zaire and Sudan Ebolaviruses.

    Directory of Open Access Journals (Sweden)

    Callie E Bounds

    Full Text Available DNA vaccination of transchromosomal bovines (TcBs with DNA vaccines expressing the codon-optimized (co glycoprotein (GP genes of Ebola virus (EBOV and Sudan virus (SUDV produce fully human polyclonal antibodies (pAbs that recognize both viruses and demonstrate robust neutralizing activity. Each TcB was vaccinated by intramuscular electroporation (IM-EP a total of four times and at each administration received 10 mg of the EBOV-GPco DNA vaccine and 10 mg of the SUDV-GPco DNA vaccine at two sites on the left and right sides, respectively. After two vaccinations, robust antibody responses (titers > 1000 were detected by ELISA against whole irradiated EBOV or SUDV and recombinant EBOV-GP or SUDV-GP (rGP antigens, with higher titers observed for the rGP antigens. Strong, virus neutralizing antibody responses (titers >1000 were detected after three vaccinations when measured by vesicular stomatitis virus-based pseudovirion neutralization assay (PsVNA. Maximal neutralizing antibody responses were identified by traditional plaque reduction neutralization tests (PRNT after four vaccinations. Neutralizing activity of human immunoglobulins (IgG purified from TcB plasma collected after three vaccinations and injected intraperitoneally (IP into mice at a 100 mg/kg dose was detected in the serum by PsVNA up to 14 days after administration. Passive transfer by IP injection of the purified IgG (100 mg/kg to groups of BALB/c mice one day after IP challenge with mouse adapted (ma EBOV resulted in 80% protection while all mice treated with non-specific pAbs succumbed. Similarly, interferon receptor 1 knockout (IFNAR(-/- mice receiving the purified IgG (100 mg/kg by IP injection one day after IP challenge with wild type SUDV resulted in 89% survival. These results are the first to demonstrate that filovirus GP DNA vaccines administered to TcBs by IM-EP can elicit neutralizing antibodies that provide post-exposure protection. Additionally, these data describe

  7. Cytotoxic activity of plants from East Azarbaijan province, Iran

    Directory of Open Access Journals (Sweden)

    M. Irani

    2017-11-01

    Full Text Available Background and objectives: Due to the high cancer mortality rates and side effects of different types of cancer treatments, discovering effective treatments without or with fewer side effects is the main purpose of many researchers all around the world. Plants play an important role in the discovery of new drugs. Iran owns rich and varied vegetation but the majority of these plants have not yet undergone chemical, pharmacological and toxicological studies. In the present study, some species from East Azarbaijan province of Iran were evaluated for cytotoxicity effects. Methods: Total methanol extract of 29 plants from 18 families were screened for their cytotoxic activities. The inhibition of cell growth for these extracts was evaluated against MCF-7, A-549, Hep-G2, HT-29 and MDBK cell lines. Their 50% inhibitions of growth (IC50 were determined by MTT assay. Moreover, cytotoxic evaluation of different fractions (ether de petrol, chloroform and methanol of the most potent species was performed. Results: Total extracts and fractions of Bryonia aspera, Centaurea salicifolia, Cuscuta chinensis, Ecbalium elaterium, Gypsophila ruscifolia, Ononis spinosa exhibited potent cytotoxic activity against one or more of the cell lines. Three of the mentioned total extracts presented cytotoxicity effects exclusively against HT-29 cells. Also three fractions (one ether de petrol and two chloroform fractions demonstrated selective cytotoxicity effects against MCF-7cells. Conclusion: It was concluded that these 6 potent species were proper candidates for identification and isolation of active ingredients with cytotoxic effects  and further studies about these species are recommended.

  8. Quantitative structure-cytotoxicity relationship of phenylpropanoid amides.

    Science.gov (United States)

    Shimada, Chiyako; Uesawa, Yoshihiro; Ishihara, Mariko; Kagaya, Hajime; Kanamoto, Taisei; Terakubo, Shigemi; Nakashima, Hideki; Takao, Koichi; Saito, Takayuki; Sugita, Yoshiaki; Sakagami, Hiroshi

    2014-07-01

    A total of 12 phenylpropanoid amides were subjected to quantitative structure-activity relationship (QSAR) analysis, based on their cytotoxicity, tumor selectivity and anti-HIV activity, in order to investigate on their biological activities. Cytotoxicity against four human oral squamous cell carcinoma (OSCC) cell lines and three human oral normal cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Tumor selectivity was evaluated by the ratio of the mean CC50 (50% cytotoxic concentration) against normal oral cells to that against OSCC cell lines. Anti-HIV activity was evaluated by the ratio of CC50 to EC50 (50% cytoprotective concentration from HIV infection). Physicochemical, structural, and quantum-chemical parameters were calculated based on the conformations optimized by the LowModeMD method followed by density functional theory (DFT) method. Twelve phenylpropanoid amides showed moderate cytotoxicity against both normal and OSCC cell lines. N-Caffeoyl derivatives coupled with vanillylamine and tyramine exhibited relatively higher tumor selectivity. Cytotoxicity against normal cells was correlated with descriptors related to electrostatic interaction such as polar surface area and chemical hardness, whereas cytotoxicity against tumor cells correlated with free energy, surface area and ellipticity. The tumor-selective cytotoxicity correlated with molecular size (surface area) and electrostatic interaction (the maximum electrostatic potential). The molecular size, shape and ability for electrostatic interaction are useful parameters for estimating the tumor selectivity of phenylpropanoid amides. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  9. 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.

  10. Supplementary Material for: Cytotoxicity and intracellular dissolution of nickel nanowires

    KAUST Repository

    Perez, Jose E.; Contreras, Maria F.; Vidal, Enrique Vilanova; Felix Servin, Laura P.; Margineanu, Michael B.; Luongo, Giovanni; Porter, Alexandra E.; Dunlop, Iain E.; Ravasi, Timothy; Kosel, Jü rgen

    2016-01-01

    The assessment of cytotoxicity of nanostructures is a fundamental step for their development as biomedical tools. As widely used nanostructures, nickel nanowires (Ni NWs) seem promising candidates for such applications. In this work, Ni NWs were synthesized and then characterized using vibrating sample magnetometry, energy dispersive X-Ray analysis, and electron microscopy. After exposure to the NWs, cytotoxicity was evaluated in terms of cell viability, cell membrane damage, and induced apoptosis/necrosis on the model human cell line HCT 116. The influence of NW to cell ratio (10:1 to 1000:1) and exposure times up to 72 hours was analyzed for Ni NWs of 5.4 μm in length, as well as for Ni ions. The results show that cytotoxicity markedly increases past 24 hours of incubation. Cellular uptake of NWs takes place through the phagocytosis pathway, with a fraction of the dose of NWs dissolved inside the cells. Cell death results from a combination of apoptosis and necrosis, where the latter is the outcome of the secondary necrosis pathway. The cytotoxicity of Ni ions and Ni NWs dissolution studies suggest a synergistic toxicity between NW aspect ratio and dissolved Ni, with the cytotoxic effects markedly increasing after 24 hours of incubation.

  11. Phytochemical and Cytotoxic Investigations of Alpinia mutica Rhizomes

    Directory of Open Access Journals (Sweden)

    Kae Shin Sim

    2011-01-01

    Full Text Available The methanol and fractionated extracts (hexane, ethyl acetate and water of Alpinia mutica (Zingiberaceae rhizomes were investigated for their cytotoxic effect against six human carcinoma cell lines, namely KB, MCF7, A549, Caski, HCT116, HT29 and non-human fibroblast cell line (MRC 5 using an in vitro cytotoxicity assay. The ethyl acetate extract possessed high inhibitory effect against KB, MCF7 and Caski cells (IC50 values of 9.4, 19.7 and 19.8 µg/mL, respectively. Flavokawin B (1, 5,6-dehydrokawain (2, pinostrobin chalcone (3 and alpinetin (4, isolated from the active ethyl acetate extract were also evaluated for their cytotoxic activity. Of these, pinostrobin chalcone (3 and alpinetin (4 were isolated from this plant for the first time. Pinostrobin chalcone (3 displayed very remarkable cytotoxic activity against the tested human cancer cells, such as KB, MCF7 and Caski cells (IC50 values of 6.2, 7.3 and 7.7 µg/mL, respectively. This is the first report of the cytotoxic activity of Alpinia mutica.

  12. Analysis of cytotoxic effects of nickel on human blood lymphocytes.

    Science.gov (United States)

    Zarei, Mohammad Hadi; Hosseini Shirazi, Seyed Farshad; Aghvami, Marjan; Salimi, Ahmad; Pourahmad, Jalal

    2018-02-01

    Nickel compounds possess many applications in different industrial processes. Human beings are exposed to nickel commonly through occupational exposure and food. Although a few studies so far have investigated the effects of nickel compounds on human lymphocytes, the complete mechanism of cytotoxicity of this metal on human lymphocytes is yet to be determined. The intention of this paper was to determine the cytotoxicity mechanism of water soluble NiCl 2 toward human lymphocytes using the accelerated cytotoxicity mechanisms screening (ACMS) technique. Human lymphocytes were isolated from the blood of healthy subjects based on Ficoll-Paque PLUS standard method. For the assessment of cell viability, lymphocytes were incubated with 0.05-1 mM NiCl 2 for 12 h. Determination of mechanistic parameters was performed 2, 4 and 6 h after treatment of cells with ½ EC50 12h , EC50 12h and 2EC50 12h of NiCl 2 . Our results demonstrate that cytotoxicity of NiCl 2 on human lymphocytes is associated with increased ROS formation, mitochondrial membrane potential collapse, glutathione depletion, lysosomal membrane damage, cellular proteolysis and activation of caspase-3 before cytotoxicity ensued.

  13. Cytotoxicity evaluation of ceramic particles of different sizes and shapes.

    Science.gov (United States)

    Yamamoto, Akiko; Honma, Rieko; Sumita, Masae; Hanawa, Takao

    2004-02-01

    When artificial hip or knee joints are implanted in the human body, they release metallic, ceramic, and polymeric debris into the surrounding tissues. The toxicity of the released particles is of two types: chemical, caused by the released soluble ions and monomers, and mechanical, a result of mechanical stimulation produced by the insoluble particles. In this study, the cytotoxicity of particles of TiO2, Al2O3, ZrO2, Si3N4, and SiC for murine fibroblasts and macrophages were examined to evaluate just their mechanical toxicity because these particles are not expected to release soluble metal ions. Different sizes and shapes of TiO2 particles were used to evaluate the effect of size and shape on particle cytotoxicity. The results suggest that the cytotoxicity of ceramic particles does not depend on their chemical species. Cytotoxicity levels were lower than those of corresponding metal ions, indicating that the mechanical toxicity of particles is lower than the chemical toxicity of released soluble ions and monomers. The differences in size did not affect the mechanical toxicity of these particles. The dendritic particles had a higher cytotoxicity level for macrophages than did spindle and spheric particles. Copyright 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 244-256, 2004

  14. A fluorescence-based rapid screening assay for cytotoxic compounds

    International Nuclear Information System (INIS)

    Montoya, Jessica; Varela-Ramirez, Armando; Estrada, Abril; Martinez, Luis E.; Garza, Kristine; Aguilera, Renato J.

    2004-01-01

    A simple fluorescence-based assay was developed for the rapid screening of potential cytotoxic compounds generated by combinatorial chemistry. The assay is based on detection of nuclear green fluorescent protein (GFP) staining of a human cervical cancer cell line (HeLa) carrying an integrated histone H2B-GFP fusion gene. Addition of a cytotoxic compound to the HeLa-GFP cells results in the eventual degradation of DNA and loss of the GFP nuclear fluorescence. Using this assay, we screened 11 distinct quinone derivatives and found that several of these compounds were cytotoxic. These compounds are structurally related to plumbagin an apoptosis-inducing naphthoquinone isolated from Black Walnut. In order to determine the mechanism by which cell death was induced, we performed additional experiments with the most cytotoxic quinones. These compounds were found to induce morphological changes (blebbing and nuclear condensation) consistent with induction of apoptosis. Additional tests revealed that the cytotoxic compounds induce both necrotic and apoptotic modes of death

  15. Identification of Glyceraldehyde-3-phosphate dehydrogenase (GAPDH as a binding protein for a 68-kDa Bacillus thuringiensis parasporal protein cytotoxic against leukaemic cells

    Directory of Open Access Journals (Sweden)

    Nadarajah Vishna

    2010-11-01

    Full Text Available Abstract Background Bacillus thuringiensis (Bt, an ubiquitous gram-positive spore-forming bacterium forms parasporal proteins during the stationary phase of its growth. Recent findings of selective human cancer cell-killing activity in non-insecticidal Bt isolates resulted in a new category of Bt parasporal protein called parasporin. However, little is known about the receptor molecules that bind parasporins and the mechanism of anti-cancer activity. A Malaysian Bt isolate, designated Bt18 produces parasporal protein that exhibit preferential cytotoxic activity for human leukaemic T cells (CEM-SS but is non-cytotoxic to normal T cells or other cancer cell lines such as human cervical cancer (HeLa, human breast cancer (MCF-7 and colon cancer (HT-29 suggesting properties similar to parasporin. In this study we aim to identify the binding protein for Bt18 in human leukaemic T cells. Methods Bt18 parasporal protein was separated using Mono Q anion exchange column attached to a HPLC system and antibody was raised against the purified 68-kDa parasporal protein. Receptor binding assay was used to detect the binding protein for Bt18 parasporal protein in CEM-SS cells and the identified protein was sent for N-terminal sequencing. NCBI protein BLAST was used to analyse the protein sequence. Double immunofluorescence staining techniques was applied to localise Bt18 and binding protein on CEM-SS cell. Results Anion exchange separation of Bt18 parasporal protein yielded a 68-kDa parasporal protein with specific cytotoxic activity. Polyclonal IgG (anti-Bt18 for the 68-kDa parasporal protein was successfully raised and purified. Receptor binding assay showed that Bt18 parasporal protein bound to a 36-kDa protein from the CEM-SS cells lysate. N-terminal amino acid sequence of the 36-kDa protein was GKVKVGVNGFGRIGG. NCBI protein BLAST revealed that the binding protein was Glyceraldehyde-3-phosphate dehydrogenase (GAPDH. Double immunofluorescence staining showed

  16. Cytotoxicity of an 125I-labelled DNA ligand

    International Nuclear Information System (INIS)

    Karagiannis, T.C.; Lobachevsky, P.N.; Martin, R.F.

    2000-01-01

    The subcellular distribution and cytotoxicity of a DNA-binding ligand [ 125 I]-Hoechst 33258 following incubation of K562 cells with the drug was investigated. The ability of a radical scavenger, dimethyl sulphoxide, to protect cells from the 125 I-decay induced cell death was also studied. Three different concentrations and specific activities of the drug were used to provide different ligand : DNA binding ratios. The results demonstrated a trend toward improved delivery of the ligand to the nucleus and to chromatin at higher ligand concentrations, with concomitant increased sensitivity to 125 I-decay induced cytotoxicity and decreased protection by dimethyl sulphoxide. This correlation of radiobiological parameters with subcellular drug distribution is consistent with the classical dogma that attributes cytotoxicity to DNA double-stranded breakage in the vicinity of the site of decay, where the high LET nature of the damage confers minimal sensitivity to radical scavenging

  17. Cytotoxic bibenzyl dimers from the stems of Dendrobium fimbriatum Hook.

    Science.gov (United States)

    Xu, Feng-Qing; Xu, Fang-Cheng; Hou, Bo; Fan, Wei-Wei; Zi, Cheng-Ting; Li, Yan; Dong, Fa-Wu; Liu, Yu-Qing; Sheng, Jun; Zuo, Zhi-Li; Hu, Jiang-Miao

    2014-11-15

    The bioassay-guided chemical investigation of the stems of Dendrobium fimbriatum Hook led to the isolation of seven first reported bibenzyl dimers with a linkage of a methylene moiety, fimbriadimerbibenzyls A-G (1-7), together with a new dihydrophenanthrene derivative (S)-2,4,5,9-tetrahydroxy-9,10-dihydrophenanthrene (8) and thirteen known compounds (9-21). The structure of the new compound was established by spectroscopic analysis. Biological evaluation of bibenzyl derivatives against five human cell lines indicated that seven of those compounds exhibited broad-spectrum and cytotoxic activities with IC50 values ranging from 2.2 to 21.2 μM. Those rare bibenzyl dimers exhibited cytotoxic activities in vitro and the cytotoxicity decreased as the number of oxygen-containing groups in the structure decreases. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Phytochemistry, cytotoxicity and antiviral activity of Eleusine indica (sambau)

    Science.gov (United States)

    Iberahim, Rashidah; Yaacob, Wan Ahmad; Ibrahim, Nazlina

    2015-09-01

    Goose grass also known as Eleusine indica (EI) is a local medicinal plant that displays antioxidant, antimicrobial and anticancer activities. The present study is to determine the phytochemical constituents, cytotoxicity and antiviral activities for both crude extract and fraction obtained from the plant. The crude extract contained more secondary metabolites compared to the hexane fraction as gauged using standard phytochemical tests. Cytotoxicity screening against Vero cells using MTT assay showed that the CC50 values for crude extract and hexane fraction were 2.07 and 5.62 mg/ml respectively. The antiviral activity towards Herpes Simplex Virus type 1 (HSV-1) was determined using plaque reduction assay. The selective indices (SI = CC50 / EC50) for both methanol extract and hexane fraction were 12.2 and 6.2 respectively. These results demonstrate that the extract prepared from E. indica possesses phytochemical compound that was non cytotoxic to the cell with potential antiviral activity.

  19. Cytotoxic components of Pereskia bleo (Kunth) DC. (Cactaceae) leaves.

    Science.gov (United States)

    Malek, Sri Nurestri Abdul; Shin, Sim Kae; Wahab, Norhanom Abdul; Yaacob, Hashim

    2009-05-06

    Dihydroactinidiolide (1) and a mixture of sterols [campesterol (2), stigmasterol (3) and beta-sitosterol (4)], together with the previously isolated individual compounds beta-sitosterol (4), 2,4-di-tert-butylphenol (5), alpha-tocopherol (6), phytol (7) were isolated from the active ethyl acetate fraction of Pereskia bleo (Kunth) DC. (Cactaceae) leaves. Cytotoxic activities of the above mentioned compounds against five human carcinoma cell lines, namely the human nasopharyngeal epidermoid carcinoma cell line (KB), human cervical carcinoma cell line (CasKi), human colon carcinoma cell line (HCT 116), human hormone-dependent breast carcinoma cell line (MCF7) and human lung carcinoma cell line (A549); and non-cancer human fibroblast cell line (MRC-5) were investigated. Compound 5 possessed very remarkable cytotoxic activity against KB cells, with an IC(50 )value of 0.81microg/mL. This is the first report on the cytotoxic activities of the compounds isolated from Pereskia bleo.

  20. Antiviral and cytotoxic activities of some Indonesian plants.

    Science.gov (United States)

    Lohézic-Le Dévéhat, F; Bakhtiar, A; Bézivin, C; Amoros, M; Boustie, J

    2002-08-01

    Ten methanolic extracts from eight Indonesian medicinal plants were phytochemically screened and evaluated for antiviral (HSV-1 and Poliovirus) and cytotoxic activities on murine and human cancer lines (3LL, L1210, K562, U251, DU145, MCF-7). Besides Melastoma malabathricum (Melastomataceae), the Indonesian Loranthaceae species among which Elytranthe tubaeflora, E. maingayi, E. globosa and Scurrula ferruginea exhibited attractive antiviral and cytotoxic activities. Piper aduncum (Piperaceae) was found active on Poliovirus. S. ferruginea was selected for further studies because of its activity on the U251 glioblastoma cells.

  1. Analogues of luteinizing hormone-releasing hormone containing cytotoxic groups.

    Science.gov (United States)

    Janáky, T; Juhász, A; Bajusz, S; Csernus, V; Srkalovic, G; Bokser, L; Milovanovic, S; Redding, T W; Rékási, Z; Nagy, A

    1992-02-01

    In an attempt to produce better cytotoxic analogues, chemotherapeutic antineoplastic radicals including an alkylating nitrogen mustard derivative of D-phenylalanine (D-melphalan), reactive cyclopropane, anthraquinone derivatives [2-(hydroxymethyl)anthraquinone and the anticancer antibiotic doxorubicin], and an antimetabolite (methotrexate) were coupled to suitably modified agonists and antagonists of luteinizing hormone-releasing hormone (LH-RH). Analogues with D-lysine6 and D-ornithine6 or N epsilon-(2,3-diaminopropionyl)-D-lysine and N delta-(2,3-diaminopropionyl)-D-ornithine were used as carriers for one or two cytotoxic moieties. The enhanced biological activities produced by the incorporation of D amino acids into position 6 of the agonistic analogues were further increased by the attachment of hydrophobic cytotoxic groups, resulting in compounds with 10-50 times higher activity than LH-RH. Most of the monosubstituted agonistic analogues showed high affinities for the membrane receptors of human breast cancer cells, while the receptor binding affinities of peptides containing two cytotoxic side chains were lower. Antagonistic carriers [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,D-Lys6,D-Ala10] LH-RH [where Nal(2) is 3-(2-naphthyl)alanine], [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,N epsilon-(2,3-diaminopropionyl)-D-Lys6,D-Ala10]LH-RH, and their D-Pal(3)3 homologs [Pal(3) is 3-(3-pyridyl)alanine] as well as [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Pal(3)3,Tyr5,N epsilon-(2,3-diamino-propionyl)-D-Lys6,D-Ala10]LH-RH were linked to cytotoxic compounds. The hybrid molecules inhibited ovulation in rats at doses of 10 micrograms and suppressed LH release in vitro. The receptor binding of cytotoxic analogues was decreased compared to the precursor peptides, although analogues with 2-(hydroxymethyl)anthraquinone hemiglutarate had high affinities. All of the cytotoxic analogues tested inhibited [3H]thymidine incorporation into DNA in cultures of human breast and prostate cancer cell lines

  2. Preferentially Cytotoxic Constituents of Andrographis paniculata and their Preferential Cytotoxicity against Human Pancreatic Cancer Cell Lines.

    Science.gov (United States)

    Lee, Sullim; Morita, Hiroyuki; Tezuka, Yasuhiro

    2015-07-01

    In the course of our search for anticancer agents based on a novel anti-austerity strategy, we found that the 70% EtOH extract of the crude drug Andrographis Herba (aerial parts of Andrographis paniculata), used in Japanese Kampo medicines, killed PANC-1 human pancreatic cancer cells preferentially in nutrient-deprived medium (NDM). Phytochemical investigation of the 70% EtOH extract led to the isolation of 21 known compounds consisting of six labdane-type diterpenes (11, 15, 17-19, 21), six flavones (5, 7, 10, 12, 14, 20), three flavanones (2, 6, 16), two sterols (3, 8), a fatty acid (1), a phthalate (4), a triterpene (9), and a monoterpene (13). Among them, 14-deoxy-11,12-didehydroandrographolide (17) displayed the most potent preferential cytotoxicity against PANC-1 and PSN-1 cells with PC50 values of 10.0 μM and 9.27 μM, respectively. Microscopical observation, double staining with ethidium bromide (EB) and acridine orange (AO), and flow cytometry with propidium iodide/annexin V double staining indicated that 14-deoxy-11,12-didehydroandrographolide (17) triggered apoptosis-like cell death in NDM with an amino acids and/or serum-sensitive mode.

  3. In vitro Antimalarial and Cytotoxic Activities of Leaf Extracts of ...

    African Journals Online (AJOL)

    efficacy of the plant leaves for treatment of malaria. Key Words: Antiplasmodial, cytotoxicity, Vernonia amygdalina leave, in vitro, Plasmodium falciparum, vero cell line. INTRODUCTION. Malaria constitutes one of the major public health problems in the world, especially in tropical. Africa, Asia and Latin America. The World.

  4. Cytotoxic activity and apoptotic induction of some edible Thai local ...

    African Journals Online (AJOL)

    inverted microscopy and DNA fragmentation using agarose gel electrophoresis. Results: P. ... However, further studies are needed to isolate the active compounds responsible for the cytotoxic ..... D-E: TL at 500 and 4,000 μg/mL. Arrows ...

  5. Urtica dioica Induces Cytotoxicity in Human Prostate Carcinoma ...

    African Journals Online (AJOL)

    In order to evaluate the involvement of caspases in UD-AQ induced cytotoxicity, the activities of caspase 3 and 9 were measured using a colorimetric assay. Following treatment of. LNCaP cells with UD-AQ extract (50 µg/ml) in 6- well plates, cells were collected by centrifugation and lysed with lysis buffer (1 % Triton X-100,.

  6. IgM-mediated opsonization and cytotoxicity in the shark.

    Science.gov (United States)

    McKinney, E C; Flajnik, M F

    1997-02-01

    Two types of cytotoxic reactions have been observed using cells from the nurse shark: spontaneous cytotoxicity mediated by cells of the macrophage lineage and antibody-dependent killing carried out by a different effector cell population. Previous data showed that removal of phagocytic cells using iron particles abolished macrophage-mediated killing, but not antibody-dependent reactions. The current study used single cell assays and showed that the effector of antibody-driven reactions was the neutrophil. Surprisingly, the mechanism of killing was shown to be phagocytosis mediated by both 7S and 19S immunoglobulin M (IgM). Reactions proceeded with as little as 0.01 microg of purified 19S or 7S IgM and were complete within 4-6 h. In contrast, purified immunoglobulin did not adsorb to macrophages and had no effect on target cell binding or cytotoxicity. Pretreatment of cells with cytochalasin D abolished the phagocytic reaction, but not spontaneous cytotoxicity. These data show that antibody-mediated killing results from opsonization and phagocytosis; the mechanism of macrophage killing is currently unknown. In addition, these data show that the shark neutrophil, not the macrophage lineage, carries a receptor for Fc mu.

  7. Activation of cytotoxic lymphocytes in patients with scrub typhus

    NARCIS (Netherlands)

    de Fost, Maaike; Chierakul, Wirongrong; Pimda, Kriangsak; Dondorp, Arjen M.; White, Nicholas J.; van der Poll, Tom

    2005-01-01

    Thai patients with scrub typhus caused by the intracellular pathogen Orientia tsutsugamushi displayed elevated plasma concentrations of granzymes A and B, interferon-gamma (IFN)-gamma-inducible protein 10, and monokine induced by IFN-gamma. These data suggest that activation of cytotoxic lymphocytes

  8. Altered effector function of peripheral cytotoxic cells in COPD

    Directory of Open Access Journals (Sweden)

    Corne Jonathan M

    2009-06-01

    Full Text Available Abstract Background There is mounting evidence that perforin and granzymes are important mediators in the lung destruction seen in COPD. We investigated the characteristics of the three main perforin and granzyme containing peripheral cells, namely CD8+ T lymphocytes, natural killer (NK; CD56+CD3- cells and NKT-like (CD56+CD3+ cells. Methods Peripheral blood mononuclear cells (PBMCs were isolated and cell numbers and intracellular granzyme B and perforin were analysed by flow cytometry. Immunomagnetically selected CD8+ T lymphocytes, NK (CD56+CD3- and NKT-like (CD56+CD3+ cells were used in an LDH release assay to determine cytotoxicity and cytotoxic mechanisms were investigated by blocking perforin and granzyme B with relevant antibodies. Results The proportion of peripheral blood NKT-like (CD56+CD3+ cells in smokers with COPD (COPD subjects was significantly lower (0.6% than in healthy smokers (smokers (2.8%, p +CD3- cells from COPD subjects were significantly less cytotoxic than in smokers (16.8% vs 51.9% specific lysis, p +CD3+ cells (16.7% vs 52.4% specific lysis, p +CD3- and NKT-like (CD56+CD3+ cells from smokers and HNS. Conclusion In this study, we show that the relative numbers of peripheral blood NK (CD56+CD3- and NKT-like (CD56+CD3+ cells in COPD subjects are reduced and that their cytotoxic effector function is defective.

  9. Kinetin (N -furfuryladenine): Cytotoxicity against MCF-7 breast ...

    African Journals Online (AJOL)

    Jane

    2011-07-06

    Jul 6, 2011 ... The cytotoxicity effect of kinetin on MCF-7 breast cancer cell lines was ... Medium (DMEM) containing 10% FBS, 2 mM glutamine, 100 units/ml ..... apoptosis of human myeloid leukemia cells by cytokinins and cytokinin ...

  10. Cytotoxic Effect and Antioxidant Activity of Bioassay- guided ...

    African Journals Online (AJOL)

    ... were investigated for their in vitro cytotoxic effect against various cancer cell lines using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5- ... In MTT assay, fractions 1, 2 and 4 from methanol extract showed the ... plant is used as antitumourigenic, antioxidant,.

  11. In-vitro cytotoxicity of biosynthesized gold nanoparticles against ...

    African Journals Online (AJOL)

    The AuNPs were evaluated by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV–Vis) spectroscopy and transmission electron microscopy (TEM). They were also assessed for cytotoxicity against SW579 cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide ...

  12. Physico-chemical characterization and cytotoxicity studies of seed ...

    African Journals Online (AJOL)

    The seeds of Khaya senegalensis were extracted using petroleum ether and methanol with the aim of determining the physico-chemical properties of the seed oil and the cytotoxicity of the two extracts. The refractive index of the oil was found to be 1.458, while the relative density was 0.953. The iodine and saponification ...

  13. Analysis of cytotoxic T cell epitopes in relation to cancer

    DEFF Research Database (Denmark)

    Stranzl, Thomas

    The human immune system is a highly adaptable system, defending our bodies against pathogens and tumor cells. Cytotoxic T cells (CTL) are cells of the adaptive immune system, capable of inducing a programmed cell death and thus able to eliminate infected or tumor cells. CTLs discriminate between...

  14. Phytochemical Screening and Cytotoxicity of Crude Extracts of ...

    African Journals Online (AJOL)

    Thin–layer chromatography (TLC) and phytochemical screening were employed to identify the chemical constituents. Cytotoxicity was characterized by 50 % inhibition (IC50) of human breast cancer cell lines (MCF-7 and MDA-MB-468) using 3-(4,5-dimethylthaizol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.

  15. Cytotoxicity testing of aqueous extract of bitter leaf (Vernonia ...

    African Journals Online (AJOL)

    Cytotoxicity testing of aqueous extract of bitter leaf (Vernonia amygdalina Del) and sniper. 1000EC (2,3 ... man and animals.1 It is estimated that 80% of the popula- ..... evaluation of waste, surface and ground water quality using the Allium test ...

  16. Physico-chemical characterization and cytotoxicity studies of seed ...

    African Journals Online (AJOL)

    GREGO

    2007-04-02

    Apr 2, 2007 ... saponification values were 88.40 and 195.58, respectively. The peroxide and acid values were 4.6 and. 2.69, respectively. Brine shrimp lethality bioassay of petroleum ether and methanol extracts of the seeds showed that the extracts were moderately cytotoxic at high concentration. The LC50 values using.

  17. The evaluation of selected ghanaian medicinal plants for cytotoxic ...

    African Journals Online (AJOL)

    Extracts of Adenia lobata root, Clerodendrum capitatum leaves, Garcinia kola stem bark, Plumbago zeylanica leaves and Vernonia conferta root, showed relatively low cytotoxic activities while extracts of Ficus asperifolia leaves, Paullinia pinnata root and Thonningia sanguinea root exhibited moderate activity (IC50 values ...

  18. Cytotoxicity of Phenol Red in Toxicity Assays for Carbon Nanoparticles

    Directory of Open Access Journals (Sweden)

    Chunhai Fan

    2012-09-01

    Full Text Available To explore the novel properties of carbon nanoparticles (CNPs in nanotoxicity assays, the adsorption of phenol red (a pH indicator for culture medium by multi-walled carbon nanotubes (MWNTs and three kinds of carbon blacks (CBs with nanosize, and its effects on cytotoxicity were studied. Results indicated that the phenol red adsorbed and delivered into cells by CBs was responsible for the toxicity to Hela cells in the medium without serum. The cellular uptake of phenol red was verified using 125I-labeling techniques. The size-dependent cytotoxicity of CBs was found to closely correlate to adsorption of phenol red, cellular uptake of phenol red-CB complexes and the amount of phenol red delivered into the cells by CBs. Although the CBs were either nontoxic or slightly toxic, as vehicles of phenol red, they played an essential role in the cytotoxicity induced by phenol red. However, MWNTs showed an intrinsic cytotoxicity independent of phenol red. The implications associated with these findings are discussed.

  19. Cytotoxicity testing of aqueous extract of bitter leaf ( Vernonia ...

    African Journals Online (AJOL)

    Cytotoxicity testing of aqueous extract of bitter leaf ( Vernonia amygdalina Del ) and sniper 1000EC (2,3 dichlorovinyl dimethyl phosphate) using the Alium cepa ... 96 hours and EC50 values at 95% confidence interval was determined from a plot of root length against sample concentrations using Microsoft Excel software.

  20. GENERATION OF CYTOTOXIC LYMPHOCYTES IN MIXED LYMPHOCYTE REACTIONS

    Science.gov (United States)

    Forman, James; Möller, Göran

    1973-01-01

    Generation of cytotoxic effector cells by a unidirectional mixed lymphocyte reaction (MLR) in the mouse H-2 system was studied using labeled YAC (H-2a) leukemia cells as targets. The responding effector cell displayed a specific cytotoxic effect against target cells of the same H-2 genotype as the stimulating cell population. Killing of syngeneic H-2 cells was not observed, even when the labeled target cells were "innocent bystanders" in cultures where specific target cells were reintroduced. Similar results were found with spleen cells taken from mice sensitized in vivo 7 days earlier. The effector cell was not an adherent cell and was not activated by supernatants from MLR. The supernatants were not cytotoxic by themselves. When concanavalin A or phytohemagglutinin was added to the cytotoxic test system, target and effector cells were agglutinated. Under these conditions, killing of H-2a target cells was observed in mixed cultures where H-2a lymphocytes were also the effector cells. These findings indicate that specifically activated, probably thymus-derived lymphocytes, can kill nonspecifically once they have been activated and providing there is close contact between effector and target cells. Thus, specificity of T cell killing appears to be restricted to recognition and subsequent binding to the targets, the actual effector phase being nonspecific. PMID:4269560

  1. Evaluation of the anti-proliferative and cytotoxic potentials of ...

    African Journals Online (AJOL)

    The partitioned aqueous and chloroform fractions obtained from the methanol extract of the leaf of Cnidoscolus aconitifolius were examined for anti-proliferative (1-30 mg/mL) and cytotoxic activities (20-400 μg/mL) using the seed radicle inhibition and tadpole mortality assays over a period of 24 and 96 h respectively.

  2. Cytotoxic activity and phytochemical analysis of Arum palaestinum Boiss.

    Directory of Open Access Journals (Sweden)

    Mai Mohammed Farid

    2015-11-01

    Conclusions: The present study is considered to be the first report on the cytotoxic activities carried out on different selected fractions and pure compounds of A. palaestinum to provide evidences for its strong antitumor activities. In addition, chrysoeriol and isovitexin compounds were isolated for the first time from the studied taxa.

  3. An efficient analysis of nanomaterial cytotoxicity based on bioimpedance

    International Nuclear Information System (INIS)

    Kandasamy, Karthikeyan; Kim, Sanghyo; Choi, Cheol Soo

    2010-01-01

    In the emerging nanotechnology field, there is an urgent need for the development of a significant and sensitive method that can be used to analyse and compare the cytotoxicities of nanomaterials such as carbon nanotubes (CNTs) and gold nanoparticles (AuNPs), since such materials can be applied as contrast agents or drug delivery carriers. The bioimpedance system possesses great potential in many medical research fields including nanotechnology. Electric cell-substrate impedance sensing (ECIS) is a particular bioimpedance system that offers a real-time, non-invasive, and quantitative measurement method for the cytotoxicity of various materials. The present work compared the cytotoxicity of AuNPs to that of purchased single-walled carbon nanotubes (SWCNTs). The size-controlled and monodispersed AuNPs were synthesized under autoclaved conditions and reduced by ascorbic acid (AA) whereas the purchased SWCNTs were used without any surface modifications. Bioimpedance results were validated by conventional WST-1 and trypan blue assays, and transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM) were performed to examine nanomaterials inside the VERO cells. This research evaluates the ability of the ECIS system compared to those of conventional methods in analyzing the cytotoxicity of AuNPs and SWCNTs with higher sensitivity under real-time conditions.

  4. Fetal Toxicity and Cytotoxicity of Lannea kerstingii Engl and Krause ...

    African Journals Online (AJOL)

    Purpose: To evaluate the fetal toxicity and cytotoxicity of L. kerstingii in pregnant rats exposed in the organogenic ... was performed and uterine horns were removed. The number of .... microplate reader (Dynatech MR 4000, .... activity, diarrhoea and vaginal bleeding. .... abnormal Savda Munziq aqueous extract in human.

  5. Urtica dioica Induces Cytotoxicity in Human Prostate Carcinoma ...

    African Journals Online (AJOL)

    Purpose: To evaluate the cytotoxic mechanisms of an extract from the leaves of the Urtica dioica (UD) plant in LNCaP prostate cancer cells. Methods: LNCaP cells were exposed to the UD extract for 24hrs and cell viability assessed using the MTT assay. Reactive oxygen species generation was assessed using the NBT ...

  6. Cytotoxic sesquiterpene lactones from the aerial parts of Inula aucheriana.

    Directory of Open Access Journals (Sweden)

    Ahmad Reza Gohari

    2015-06-01

    Full Text Available Inula aucheriana DC is a member of the family Asteraceae which is known to produce cytotoxic secondary metabolites noted as sesquiterpene lactones. In the present study, sesquiterpene lactones inuchinenolide B, 6-deoxychamissonolide (stevin and 14-acetoxy-1β,5α,7αH-4β-hydroxy-guai-9(10,11(13-dien-12,8α-olide were isolated from I. aucheriana. Inuchinenolide B and 14-acetoxy-1β,5α,7αH-4β-hydroxy-guai-9(10,11(13-dien-12,8α-olide were further evaluated by the MTT (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide assay to demonstrate cytotoxic activity with IC50 values of (56.6, 19.0, (39.0, 11.8, and (55.7, 15.3 μg/mL against HepG-2, MCF-7 and A-549 cells, respectively. The cytotoxic activity of the two evaluated sesquiterpene lactones partly explains the cytotoxic activity that was previously observed for the extracts of Inula aucheriana. The isolated compounds could be further investigated in cancer research studies.

  7. In vitro anticancer activity and cytotoxicity of some papaver alkaloids ...

    African Journals Online (AJOL)

    Materials and Methods: The Vero and HeLa cell lines were treated with various concentrations (1-300 μg/mL) of alkaloids for 48 h. Values for cytotoxicity measured by MTT assay were expressed as the concentration that causes a 50% decrease in cell viability (IC50) (μg/mL). Results: Berberine and macranthine were the ...

  8. Cytotoxicity and antibacterial studies of iridoids and phenolic ...

    African Journals Online (AJOL)

    The latex of Himatanthus sucuuba (Spruce) Woodson, used popularly in the Amazon for the treatment of tumors, gastritis, inflammations and infections, was evaluated for cytotoxicity and antibacterial activities. The iridoid lactones, plumericin and isoplumericin were isolated from latex by bioassay fractionation and were ...

  9. Phytochemistry, cytotoxicity and apoptosis studies of β-sitosterol-3 ...

    African Journals Online (AJOL)

    Materials and methods: In this study, compounds from the leaves and bark of this plant were isolated and tested for their cytotoxicity and apoptosis induction in two human cancer cell lines (hepatocellular carcinoma (HepG2) and colorectal carcinoma (Caco-2)) and a non-cancer cell line (embryonic kidney (HEK293)).

  10. Preparation and in-vitro cytotoxicity of zinc oxide nanoparticles ...

    African Journals Online (AJOL)

    The cytotoxicity of the NPs against human osteoarthritic chondrocytes was studied using eosin Y test method. Results: The change in color of the reaction solution from colorless to pale white within 1 h indicated the formation of ZnO NPs. FTIR results revealed coating of plant polyphenols on ZnO NPs surface while XRD and ...

  11. MODERATE CYTOTOXICITY OF PROANTHOCYANIDINS TO HUMAN TUMOR-CELL LINES

    NARCIS (Netherlands)

    KOLODZIEJ, H; HABERLAND, C; WOERDENBAG, HJ; KONINGS, AWT

    In the present study the cytotoxicity of 16 proanthocyanidins was evaluated in GLC(4), a human small cell lung carcinoma cell line, and in COLO 320, a human colorectal cancer cell line, using the microculture tetrazolium (MTT) assay. With IC50 values ranging from 18 to >200 mu m following continuous

  12. Three New Cytotoxic ent-Kaurane Diterpenes from Isodon excisoides

    Directory of Open Access Journals (Sweden)

    Li-Ping Dai

    2015-09-01

    Full Text Available Three types of ent-kaurane diterpenoids were isolated from the aerial parts of Isodon excisoides, including three new diterpenoids, 1α,7α,14β-trihydroxy-20-acetoxy-ent-kaur-15-one (1; 1α,7α,14β,18-tetrahydroxy-20-acetoxy-ent-kaur-15-one (2; and 1α-acetoxy-14β-hydroxy-7α,20-epoxy-ent-kaur-16-en-15-one (3; together with six known diterpenes henryin (4; kamebanin (5; reniformin C (6; kamebacetal A (7; kamebacetal B (8; and oridonin (9. The structures of the isolated compounds were elucidated by means of nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry in conjunction with published data for their analogs, as well as their fragmentation patterns. Compounds 5 and 9 were isolated from Isodon excisoides for the first time. To explore the structure-activity relationships of the isolated compounds, they were tested for their cytotoxic effects against five human cancer cell lines: HCT-116, HepG2, A2780, NCI-H1650, and BGC-823. Most of the isolated compounds showed certain cytotoxic activity against the five cancer cell lines with IC50 values ranging from 1.09–8.53 µM. Among the tested compounds, compound 4 exhibited the strongest cytotoxic activity in the tested cell lines, with IC50 values ranging from 1.31–2.07 µM. Compounds 1, 6, and 7 exhibited selective cytotoxic activity.

  13. Chemical composition, cytotoxicity and antioxidant activities of the ...

    African Journals Online (AJOL)

    The species of the genus Citrus (Rutaceae) have been widely used in traditional medicine. In this study, the essential oil was extracted from the leaves of Citrus aurantium and its cytotoxicity effect on six tumor cell lines and a normal cell line was studied. Furthermore, antioxidant potential of the oil was tested by 2, ...

  14. Phytochemical screening, cytotoxicity and acute toxicity of Annona ...

    African Journals Online (AJOL)

    Phytochemical screening, cytotoxicity and acute toxicity of Annona vepretorum Mart (Annonaceae) leaf extracts. Mariana G e Silva, Ana P de Oliveira, Camila de S Araújo, Érica M de Lavor, Juliane C Silva, Rosemairy L Mendes, Cláudia do Ó Pessoa, Marcília P Costa, Jackson R G da S Almeida ...

  15. Efficiency of immunotoxin cytotoxicity is modulated by the intracellular itinerary.

    Directory of Open Access Journals (Sweden)

    Lori L Tortorella

    Full Text Available Pseudomonas exotoxin-based immunotoxins, including LMB-2 (antiTac(F(v-PE38, are proposed to traffic to the trans-Golgi network (TGN and move by a retrograde pathway to the endoplasmic reticulum, where they undergo translocation to the cytoplasm, a step that is essential for cytotoxicity. The retrograde transport pathways used by LMB-2 are not completely understood, so it is unclear if transit through specific organelles is critical for maximal cytotoxic activity. In this study, we used Chinese hamster ovary (CHO cell lines that express chimeric constructs of CD25, the Tac antigen, attached to the cytoplasmic domain of the TGN-targeted transmembrane proteins, TGN38 and furin. These chimeras are both targeted to the TGN, but the itineraries they follow are quite different. LMB-2 was incubated with the two cell lines, and the efficiency of cell killing was determined using cell viability and cytotoxicity assays. LMB-2 that is targeted through the endocytic recycling compartment to the TGN via Tac-TGN38 kills the cells more efficiently than immunotoxins delivered through the late endosomes by Tac-furin. Although the processing to the 37 kDa active fragment was more efficient in Tac-furin cells than in Tac-TGN38 cells, this was not associated with enhanced cytotoxicity - presumably because the toxin was also degraded more rapidly in these cells. These data indicate that trafficking through specific organelles is an important factor modulating toxicity by LMB-2.

  16. Cytotoxic Activities of Several Geranyl-Substituted Flavanones

    Czech Academy of Sciences Publication Activity Database

    Šmejkal, K.; Svačinová, Jana; Šlapetová, T.; Schneiderová, K.; Dall’Acqua, S.; Innocenti, G.; Závalová, V.; Kollár, P.; Chudík, S.; Marek, R.; Julínek, O.; Urbanová, M.; Kartal, M.; Csöllei, M.; Doležal, Karel

    2010-01-01

    Roč. 73, č. 4 (2010), s. 568-572 ISSN 0163-3864 R&D Projects: GA MŠk(CZ) LC06030; GA ČR GD522/08/H003 Institutional research plan: CEZ:AV0Z50380511 Keywords : flavanones * geranyl * cytotoxicity Subject RIV: BO - Biophysics Impact factor: 2.872, year: 2010

  17. chemical constituents and cytotoxicity of some tanzanian wild

    African Journals Online (AJOL)

    Mgina

    C - 6), 115.9 (C - 3, C - 5), 161 (C - 4) and. 190.7 (CHO). Brine Shrimp Lethality Bioassays. The cytotoxicity of ... HO. 3. Both the 1H and 13C NMR spectra of compound 2 exhibited signals that suggested the presence of two olefinic double bonds instead of three as shown in ergosterol. The 13C NMR spectrum, unlike.

  18. Klebsiella pneumoniae triggers a cytotoxic effect on airway epithelial cells

    Directory of Open Access Journals (Sweden)

    Llobet-Brossa Enrique

    2009-08-01

    Full Text Available Abstract Background Klebsiella pneumoniae is a capsulated Gram negative bacterial pathogen and a frequent cause of nosocomial infections. Despite its clinical relevance, little is known about the features of the interaction between K. pneumoniae and lung epithelial cells on a cellular level, neither about the role of capsule polysaccharide, one of its best characterised virulence factors, in this interaction. Results The interaction between Klebsiella pneumoniae and cultured airway epithelial cells was analysed. K. pneumoniae infection triggered cytotoxicity, evident by cell rounding and detachment from the substrate. This effect required the presence of live bacteria and of capsule polysaccharide, since it was observed with isolates expressing different amounts of capsule and/or different serotypes but not with non-capsulated bacteria. Cytotoxicity was analysed by lactate dehydrogenase and formazan measurements, ethidium bromide uptake and analysis of DNA integrity, obtaining consistent and complementary results. Moreover, cytotoxicity of non-capsulated strains was restored by addition of purified capsule during infection. While a non-capsulated strain was avirulent in a mouse infection model, capsulated K. pneumoniae isolates displayed different degrees of virulence. Conclusion Our observations allocate a novel role to K. pneumoniae capsule in promotion of cytotoxicity. Although this effect is likely to be associated with virulence, strains expressing different capsule levels were not equally virulent. This fact suggests the existence of other bacterial requirements for virulence, together with capsule polysaccharide.

  19. Cytotoxicity and antimicrobial activity of Salvia officinalis L. flowers ...

    African Journals Online (AJOL)

    In this study a comparison of the Cytotoxicity and antimicrobial action of the aqueous and 70% methanol extracts from the flower of the herbal species Salvia officinalis L. (Lamiaceae), originating from Sudan was carried out. Material and Methods: Aqueous, and aquatic methanolic extracts of S. officinalis was investigated for ...

  20. In vitro cytotoxicity of biosynthesized titanium dioxide nanoparticles ...

    African Journals Online (AJOL)

    The FT-IR spectrum of C. tamala leaf extract showed that the biomolecules were potentially involved in reduction processes. The negative zeta potential of -14 mV indicated that the NPs were stable and discrete while their crystalline nature was confirmed by XRD. Cytotoxicity analysis showed that the TiO2 NPs exhibit a ...

  1. Cytotoxic and toxicogenomic effects of silibinin in bladder cancer

    Indian Academy of Sciences (India)

    Silibinin is a natural phenol found in the seeds of the milk thistle plant. Recent data have shown its effectiveness forpreventing/treating bladder tumours. Therefore, in this study we investigated the cytotoxic and toxicogenetic activityof silibinin in bladder cancer cells with different TP53 statuses. Two bladder urothelial ...

  2. Cytotoxicity, Total Phenolic Contents and Antioxidant Activity of the ...

    African Journals Online (AJOL)

    The leaves of Annona muricata were extracted using ethanol and the extracts were evaluated for cytotoxicity using Brine Shrimp Lethality Assay, total phenolic content (TPC) and antioxidant activity using DPPH radical scavenging assay. The crude extract showed 73.33 % mortality at 1000 μg/mL concentration and its ...

  3. In Vitro Screening of Cytotoxic, Antimicrobial and Antioxidant ...

    African Journals Online (AJOL)

    Purpose: To evaluate the in vitro cytotoxic, antioxidant and antimicrobial activities of Clinacanthus nutans extracts and semi-fractions. Method: The plant was subjected to cold solvent extraction to produce petroleum ether, ethyl acetate and methanol crude extracts, followed by isolation using bioassay-guided fractionation.

  4. Cytotoxicity against MCF-7 breast cancer cell line and interaction ...

    African Journals Online (AJOL)

    N6-furfuryladenine (kinetin) is a cytokinin growth factor with several biological effects observed in human cells and fruit flies. Kinetin exists naturally in the DNA of almost all organisms tested so far, including human cells and various plants. The cytotoxicity effect of kinetin on MCF-7 breast cancer cell lines was measured by ...

  5. Cytotoxic T-Lymphocyte Antigen-2 alpha participates in axial ...

    African Journals Online (AJOL)

    Cytotoxic T-lymphocyte antigen-2 alpha (CTLA-2α) has been discovered and expressed in mouse activated T-cells and mast cells. Structurally, it is homologous to the proregion of mouse cathepsin L, a lysosomal cystein proteinase. Expressed recombinant CTLA-2α is shown to exhibit selective inhibition to cathepsin L and ...

  6. Changes in Actin Organization During the Cytotoxic Process

    NARCIS (Netherlands)

    Radosevic, K.; Radosevic, Katarina; van Leeuwen, Anne Marie T.; Segers-Nolten, Gezina M.J.; Figdor, Carl; de Grooth, B.G.; Greve, Jan

    1994-01-01

    Changes in organization of F-actin during the cytotoxic process between NK and K562 cells have been observed and studied using confpcal laser scanning microscopy and quantitative fluorescence microscopy. An increase in F-actin content and orientation of F-actin towards the target cell have been

  7. Antibacterial and Cytotoxic Activity of Compounds Isolated from Flourensia oolepis

    Directory of Open Access Journals (Sweden)

    Mariana Belén Joray

    2015-01-01

    Full Text Available The antibacterial and cytotoxic effects of metabolites isolated from an antibacterial extract of Flourensia oolepis were evaluated. Bioguided fractionation led to five flavonoids, identified as 2′,4′-dihydroxychalcone (1, isoliquiritigenin (2, pinocembrin (3, 7-hydroxyflavanone (4, and 7,4′-dihydroxy-3′-methoxyflavanone (5. Compound 1 showed the highest antibacterial effect, with minimum inhibitory concentration (MIC values ranging from 31 to 62 and 62 to 250 μg/mL, against Gram-positive and Gram-negative bacteria, respectively. On further assays, the cytotoxic effect of compounds 1–5 was determined by MTT assay on acute lymphoblastic leukemia (ALL and chronic myeloid leukemia (CML cell lines including their multidrug resistant (MDR phenotypes. Compound 1 induced a remarkable cytotoxic activity toward ALL cells (IC50 = 6.6–9.9 μM and a lower effect against CML cells (IC50 = 27.5–30.0 μM. Flow cytometry was used to analyze cell cycle distribution and cell death by PI-labeled cells and by Annexin V/PI staining, respectively. Upon treatment, 1 induced cell cycle arrest in the G2/M phase accompanied by a strong induction of apoptosis. These results describe for the first time the antibacterial metabolites of F. oolepis extract, with 1 being the most effective. This chalcone also emerges as a selective cytotoxic agent against sensitive and resistant leukemic cells, highlighting its potential as a lead compound.

  8. Anti-inflammatory, cytotoxic and antioxidant effects of methanolic ...

    African Journals Online (AJOL)

    ... 67.05μg/ml (ABTS). Methanol extract was able to inhibit inflammation by in vitro about 85-90% (HRBC stabilization method) and in vivo about 40-45% (Paw oedema method) anti-inflammatory assays compared to standard produced 50.04% at 6h period. In cytotoxicity assay (MTT assay) methanolic extract exhibited IC50 ...

  9. Cytotoxicity of p-chloroamphetamine in dimethylhydrazine-induced carcinomata of rat colon.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1979-01-01

    Previous studies have shown that several serotonin-related compounds are cytotoxic to dimethylhydrazine-induced carcinomata of the colon of rat. This paper reports the cytotoxicity of another serotonin-related compound, p-chloroamphetamine.

  10. DNA and factor VII-activating protease protect against the cytotoxicity of histones

    NARCIS (Netherlands)

    Marsman, Gerben; von Richthofen, Helen; Bulder, Ingrid; Lupu, Florea; Hazelzet, Jan; Luken, Brenda M.; Zeerleder, Sacha

    2017-01-01

    Circulating histones have been implicated as major mediators of inflammatory disease because of their strong cytotoxic effects. Histones form the protein core of nucleosomes; however, it is unclear whether histones and nucleosomes are equally cytotoxic. Several plasma proteins that neutralize

  11. Cytotoxic Constituents from the Leaves of Zanthoxylum schinifolium

    International Nuclear Information System (INIS)

    Fang, Zhe; Min, Byung Sun; Kim, Ae Kyong; Woo, Mi Hee; Jun, Do Youn; Kim, Young Ho

    2010-01-01

    The roots, stems, pericarps, and seeds of Z. schinifolium were each extracted with MeOH, and the leaves were extracted with 80% MeOH and concentrated. These extracts were examined on MTT for cytotoxicity against Jurkat T cell clone E6.1. The results showed that the leaves extract had the strongest MTT cytotoxicity. The MeOH extract of Z. schinifolium leaves was subsequently fractionated into four parts: methylene chloride, ethyl acetate, n-butanol and water. These fractions were examined on MTT for cytotoxicity. The results showed that the methylene chloride fraction exhibited the strongest MTT cytotoxicity. Chromatographic separation of the methylene chloride and butanol fractions had yielded a quinolin (1), three phenylpropanoids (2, 3, 12), four coumarins (4 ∼ 7), three triterpenoids (8 ∼ 10), an alkaloid (11), an alcohol glucoside (13) and three monoterpene glucosides (14, 15, 16). One of these compounds were identified as new threo-6-amino-5-hydroxy-5-methyl-1,3-oxazinan-4-one (11) together with fifteen known, 3-heptyl-2-methylisoquinolin-1(2H)-one (1), integrifoliodiol (2), cuspidiol (3), bergapten (4), aurapten (5), 8-hydroxy-7-methoxy-chromen-2-one (6), 6,7-dimethoxy-2H-naphthalen-1-one (7), lupeol (8), lupeone (9), β-sitosterol (10), syringin (12), 2-propyl alchol β-D-glucopyranoside (13), vomifoliol-9-O-β-D-glucopyranoside (14), betulalbuside A (15) and cnidioside C (16) on the basis of spectroscopic and chemical evidences. All of the compounds were isolated for the first time from this plant except 5 and 7. In the MTT cytotoxicity assay against Jurkat T cell clone E6.1, IC 50 values of cuspidiol (3) and auraptene (5) were obtained at 7.3 μg/mL and 16.5 μg/mL, respectively

  12. Cytotoxic Constituents from the Leaves of Zanthoxylum schinifolium

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Zhe; Min, Byung Sun; Kim, Ae Kyong; Woo, Mi Hee [Catholic Univ. of Daegu, Gyeongsan (Korea, Republic of); Jun, Do Youn; Kim, Young Ho [Kyungpook National Univ., Daegu (Korea, Republic of)

    2010-04-15

    The roots, stems, pericarps, and seeds of Z. schinifolium were each extracted with MeOH, and the leaves were extracted with 80% MeOH and concentrated. These extracts were examined on MTT for cytotoxicity against Jurkat T cell clone E6.1. The results showed that the leaves extract had the strongest MTT cytotoxicity. The MeOH extract of Z. schinifolium leaves was subsequently fractionated into four parts: methylene chloride, ethyl acetate, n-butanol and water. These fractions were examined on MTT for cytotoxicity. The results showed that the methylene chloride fraction exhibited the strongest MTT cytotoxicity. Chromatographic separation of the methylene chloride and butanol fractions had yielded a quinolin (1), three phenylpropanoids (2, 3, 12), four coumarins (4 ∼ 7), three triterpenoids (8 ∼ 10), an alkaloid (11), an alcohol glucoside (13) and three monoterpene glucosides (14, 15, 16). One of these compounds were identified as new threo-6-amino-5-hydroxy-5-methyl-1,3-oxazinan-4-one (11) together with fifteen known, 3-heptyl-2-methylisoquinolin-1(2H)-one (1), integrifoliodiol (2), cuspidiol (3), bergapten (4), aurapten (5), 8-hydroxy-7-methoxy-chromen-2-one (6), 6,7-dimethoxy-2H-naphthalen-1-one (7), lupeol (8), lupeone (9), β-sitosterol (10), syringin (12), 2-propyl alchol β-D-glucopyranoside (13), vomifoliol-9-O-β-D-glucopyranoside (14), betulalbuside A (15) and cnidioside C (16) on the basis of spectroscopic and chemical evidences. All of the compounds were isolated for the first time from this plant except 5 and 7. In the MTT cytotoxicity assay against Jurkat T cell clone E6.1, IC{sub 50} values of cuspidiol (3) and auraptene (5) were obtained at 7.3 μg/mL and 16.5 μg/mL, respectively.

  13. Cytotoxic and antibacterial naphthoquinones from an endophytic fungus, Cladosporium sp.

    Directory of Open Access Journals (Sweden)

    Md. Imdadul Huque Khan

    Full Text Available Objective: Endophytes have the potential to synthesize various bioactive secondary metabolites. The aim of the study was to find new cytotoxic and antibacterial metabolites from endophytic fungus, Cladosporium sp. isolated from the leaves of Rauwolfia serpentina (L. Benth. ex Kurz. (Fam: Apocyanaceae. Materials and methods: The endophytic fungus was grown on potato dextrose agar medium and extracted using ethyl acetate. Secondary metabolites were isolated by chromatographic separation and re-crystallization, and structures were confirmed by 1H NMR, 13C NMR and mass spectroscopic data. The cytotoxicity was determined by WST-1 assay and brine shrimp lethality bioassay, while antibacterial activity was assessed by disc diffusion method. Results: Two naphthoquinones, namely anhydrofusarubin (1 and methyl ether of fusarubin (2, were isolated from Cladosporium sp. The isolated compounds 1 and 2, by WST-1 assay against human leukemia cells (K-562 showed potential cytotoxicity with IC50 values of 3.97 μg/mL and 3.58 μg/mL, respectively. Initial screening of crude ethyl acetate extract and column fractions F-8 and F-10 exhibited noticeable cytotoxicity to brine shimp nauplii with LC50 values of 42.8, 1.2 and 2.1 μg/mL, respectively. Moreover, the isolated compound 2 (40 μg/disc showed prominent activities against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus megaterium with an average zone of inhibition of 27 mm, 25 mm, 24 mm and 22 mm, respectively and the activities were compared with kanamycin (30 μg/disc. Conclusion: Our findings indicate that anhydrofusarubin (1 and methyl ether of fusarubin (2 might be useful lead compounds to develop potential cytotoxic and antimicrobial drugs. Keywords: Endophytic fungi, Cladosporium species, Fusarubin, Cytoxicity, Antibacterial activity

  14. Cystatin F as a regulator of immune cell cytotoxicity.

    Science.gov (United States)

    Kos, Janko; Nanut, Milica Perišić; Prunk, Mateja; Sabotič, Jerica; Dautović, Esmeralda; Jewett, Anahid

    2018-05-10

    Cysteine cathepsins are lysosomal peptidases involved in the regulation of innate and adaptive immune responses. Among the diverse processes, regulation of granule-dependent cytotoxicity of cytotoxic T-lymphocytes (CTLs) and natural killer (NK) cells during cancer progression has recently gained significant attention. The function of cysteine cathepsins is regulated by endogenous cysteine protease inhibitors-cystatins. Whereas other cystatins are generally cytosolic or extracellular proteins, cystatin F is present in endosomes and lysosomes and is thus able to regulate the activity of its target directly. It is delivered to endosomal/lysosomal vesicles as an inactive, disulphide-linked dimer. Proteolytic cleavage of its N-terminal part leads to the monomer, the only form that is a potent inhibitor of cathepsins C, H and L, involved in the activation of granzymes and perforin. In NK cells and CTLs the levels of active cathepsin C and of granzyme B are dependent on the concentration of monomeric, active cystatin F. In tumour microenvironment, inactive dimeric cystatin F can be secreted from tumour cells or immune cells and further taken up by the cytotoxic cells. Subsequent monomerization and inhibition of cysteine cathepsins within the endosomal/lysosomal vesicles impairs granzyme and perforin activation, and provokes cell anergy. Further, the glycosylation pattern has been shown to be important in controlling secretion of cystatin F from target cells, as well as internalization by cytotoxic cells and trafficking to endosomal/lysosomal vesicles. Cystatin F is therefore an important mediator used by bystander cells to reduce NK and T-cell cytotoxicity.

  15. Cytotoxicity of ferrite particles by MTT and agar diffusion methods for hyperthermic application

    International Nuclear Information System (INIS)

    Kim, Dong-Hyun; Lee, Se-Ho; Kim, Kyoung-Nam; Kim, Kwang-Mahn; Shim, In-Bo; Lee, Yong-Keun

    2005-01-01

    We investigated the cytotoxicity of the prepared various ferrites (Fe-, Li-, Ni/Zn/Cu-, Ba-, Sr-, Co-, Co/Ni-ferrites) using MTT assay as well as agar diffusion method. Their cytotoxicity was compared with that of alginate-encapsulated ferrites. In the MTT assay, Fe 3 O 4 and SrFe 12 O 19 ferrite showed the highest cell viability of 90%. Alginate-encapsulated Ba-ferrite was ranked mildly cytotoxic, whereas their ferrite particles were ranked cytotoxic

  16. Cytotoxic and cytoprotective activities of curcumin. Effects on paracetamol-induced cytotoxicity, lipid peroxidation and glutathione depletion in rat hepatocytes

    NARCIS (Netherlands)

    Donatus, I A; Sardjoko,; Vermeulen, N P

    1990-01-01

    The cytoprotective effect of curcumin, a natural constituent of Curcuma longa, on the cytotoxicity of paracetamol in rat hepatocytes was studied. Paracetamol was selected as a model-toxin, since it is known to be bioactivated by 3-methylcholanthrene inducible cytochromes P450 presumably to

  17. Cytotoxic drug sensitivity testing of tumor cells from patients with ovarian carcinoma using the fluorometric microculture cytotoxicity assay (FMCA).

    Science.gov (United States)

    Csoka, K; Larsson, R; Tholander, B; Gerdin, E; de la Torre, M; Nygren, P

    1994-08-01

    The automated fluorometric microculture cytotoxicity assay (FMCA) is based on the measurement of fluorescence generated from cellular hydrolysis of fluorescein diacetate (FDA) to fluorescein by viable cells after a 72-hr culture period in microtiter plates. The FMCA was adopted for chemosensitivity testing of tumor cells from patients with ovarian carcinoma. Thirty-seven samples of solid tumors and malignant effusions were obtained from 35 patients at diagnosis or relapse. Tumor cells from solid samples and effusions were prepared by enzymatic digestion and centrifugation, respectively, followed by Percoll or Ficoll purification. The fluorescence was proportional to the number of cells/well and considerably higher in tumor cells than in contaminating normal cells. The effect of up to 19 cytotoxic drugs was successfully assessed in 70% of the samples and there was a good correlation between drug sensitivity data reported by the FMCA and the DiSC assay performed in parallel. The overall drug sensitivity pattern in vitro corresponded well to the clinical experience. The effect of cisplatin varied considerably between patients and resistance was found also in cases not previously exposed to cytotoxic drugs. The FMCA is a rapid and simple method that seems to report clinically relevant cytotoxic drug sensitivity data in ovarian carcinomas. In the future, this method may contribute to optimizing chemotherapy by assisting in individualized drug selection and new drug development.

  18. Evaluation of the cytotoxicity of dihydroxytryptamines and 5-hydroxytryptamine antagonists as cytotoxic agents in dimethylhydrazine-induced adenocarcinomata.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1978-01-01

    The cytotoxicity of 5,6-dihydroxytryptamine (5,6-DHT), 5,7-dihydroxytryptamine (5,7-DHT), bromolysergic acid diethylamide (BOL), methysergide, and cyproheptadine, and also of 5,6-DHT together with either BOL, methysergide, or cyproheptadine in dimethylhydrazine-induced (DMH) carcinomata of rat colon was evaluated by estimating the percentage of necrotic cells in histological sections of tissues taken 15 h after injection of each of the drugs. In addition, the influence of methysergide and cyproheptadine on the tumour cell mitotic rate was estimated by means of a stathmokinetic technique. Both 5,6-DHT and 5,7-DHT were cytotoxic at each dose tested and for each of these agents the percentage of necrotic cells was directly correlated with the dose of drug used. BOL was not found to be cytotoxic to the colonic carcinomata, whereas both methysergide and cyproheptadine did cause detectable tumour cell necrosis. Methysergide was also found to accelerate tumour cell proliferation, whereas cyproheptadine did not. BOL competitively inhibited the cytotoxicity of 5,6-DHT and neither methysergide nor cyproheptadine potentiated the effect of 5,6 DHT.

  19. Identification of stable cytotoxic factors in the gas phase extract of cigarette smoke and pharmacological characterization of their cytotoxicity.

    Science.gov (United States)

    Noya, Yoichi; Seki, Koh-Ichi; Asano, Hiroshi; Mai, Yosuke; Horinouchi, Takahiro; Higashi, Tsunehito; Terada, Koji; Hatate, Chizuru; Hoshi, Akimasa; Nepal, Prabha; Horiguchi, Mika; Kuge, Yuji; Miwa, Soichi

    2013-12-06

    Smoking is a major risk factor for atherosclerotic vascular diseases, but the mechanism for its genesis is unknown. We have recently shown that the gas phase of cigarette smoke (nicotine- and tar-free cigarette smoke extract; CSE) likely to reach the systemic circulation contains stable substances which cause cytotoxicity like plasma membrane damage and cell death in cultured cells, and also that the plasma membrane damage is caused through sequential activation of protein kinase C (PKC) and NADPH oxidase (NOX) and the resulting generation of reactive oxygen species (PKC/NOX-dependent mechanism), whereas cell death is caused through PKC/NOX-dependent and -independent mechanisms. To identify these stable substances, the CSE was prepared by passing the main-stream smoke of 10 cigarettes through a Cambridge glass fiber filter, trapping of the smoke in a vessel cooled at -80°C, and subsequent dissolution in 10ml of water. The CSE was fractionated into nine fractions using reversed-phase HPLC, and each fraction was screened for cytotoxicity in cultured cells, using propidium iodide uptake assay for cell membrane damage and MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] reduction assay for cell viability. The cytotoxicity was positive in two of the nine fractions (Fr2 and Fr5). After extraction of the active fractions into dichloromethane, GC/MS analysis identified 2-cyclopenten-1-one (CPO) in Fr5 but none in Fr2. After derivatization of the active fractions with O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine hydrochloride, GC/MS analysis identified acrolein, acetone and propionaldehyde in Fr2, and methyl vinyl ketone (MVK) in Fr5. After 4-h incubation, authentic acrolein and MVK induced concentration-dependent cytotoxicity with EC50 values of 75.9±8.2 and 47.0±8.0μM (mean±SEM; n=3), respectively, whereas acetone, propionaldehyde and CPO were without effect. However, after 24-h incubation, CPO induced concentration

  20. CEA/CD3-bispecific T cell-engaging (BiTE) antibody-mediated T lymphocyte cytotoxicity maximized by inhibition of both PD1 and PD-L1.

    Science.gov (United States)

    Osada, Takuya; Patel, Sandip P; Hammond, Scott A; Osada, Koya; Morse, Michael A; Lyerly, H Kim

    2015-06-01

    Bispecific T cell-engaging (BiTE) antibodies recruit polyclonal cytotoxic T cells (CTL) to tumors. One such antibody is carcinoembryonic antigen (CEA) BiTE that mediates T cell/tumor interaction by simultaneously binding CD3 expressed by T cells and CEA expressed by tumor cells. A widely operative mechanism for mitigating cytotoxic T cell-mediated killing is the interaction of tumor-expressed PD-L1 with T cell-expressed PD-1, which may be partly reversed by PD-1/PD-L1 blockade. We hypothesized that PD-1/PD-L1 blockade during BiTE-mediated T cell killing would enhance CTL function. Here, we determined the effects of PD-1 and PD-L1 blockade during initial T cell-mediated killing of CEA-expressing human tumor cell lines in vitro, as well as subsequent T cell-mediated killing by T lymphocytes that had participated in tumor cell killing. We observed a rapid upregulation of PD-1 expression and diminished cytolytic function of T cells after they had engaged in CEA BiTE-mediated killing of tumors. T cell cytolytic activity in vitro could be maximized by administration of anti-PD-1 or anti-PD-L1 antibodies alone or in combination if applied prior to a round of T cell killing, but T cell inhibition could not be fully reversed by this blockade once the T cells had killed tumor. In conclusion, our findings demonstrate that dual blockade of PD-1 and PD-L1 maximizes T cell killing of tumor directed by CEA BiTE in vitro, is more effective if applied early, and provides a rationale for clinical use.

  1. Cytotoxicity of metal and semiconductor nanoparticles indicated by cellular micromotility.

    Science.gov (United States)

    Tarantola, Marco; Schneider, David; Sunnick, Eva; Adam, Holger; Pierrat, Sebastien; Rosman, Christina; Breus, Vladimir; Sönnichsen, Carsten; Basché, Thomas; Wegener, Joachim; Janshoff, Andreas

    2009-01-27

    In the growing field of nanotechnology, there is an urgent need to sensitively determine the toxicity of nanoparticles since many technical and medical applications are based on controlled exposure to particles, that is, as contrast agents or for drug delivery. Before the in vivo implementation, in vitro cell experiments are required to achieve a detailed knowledge of toxicity and biodegradation as a function of the nanoparticles' physical and chemical properties. In this study, we show that the micromotility of animal cells as monitored by electrical cell-substrate impedance analysis (ECIS) is highly suitable to quantify in vitro cytotoxicity of semiconductor quantum dots and gold nanorods. The method is validated by conventional cytotoxicity testing and accompanied by fluorescence and dark-field microscopy to visualize changes in the cytoskeleton integrity and to determine the location of the particles within the cell.

  2. Interference of magnesium corrosion with tetrazolium-based cytotoxicity assays.

    Science.gov (United States)

    Fischer, Janine; Prosenc, Marc H; Wolff, Martin; Hort, Norbert; Willumeit, Regine; Feyerabend, Frank

    2010-05-01

    Magnesium (Mg) alloys are promising materials for the development of biodegradable implants. However, the current in vitro test procedures for cytotoxicity, cell viability and proliferation are not always suitable for this class of materials. In this paper we show that tetrazolium-salt-based assays, which are widely used in practice, are influenced by the corrosion products of Mg-based alloys. Corroded Mg converts tetrazolium salts to formazan, leading to a higher background and falsifying the results of cell viability. Tetrazolium-based assays are therefore not a useful tool for testing the cytotoxicity of Mg in static in vitro assays. Copyright (c) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. Reprint of: Improved cytotoxicity testing of magnesium materials

    International Nuclear Information System (INIS)

    Fischer, Janine; Pröfrock, Daniel; Hort, Norbert; Willumeit, Regine; Feyerabend, Frank

    2011-01-01

    Metallic magnesium (Mg) and its alloys are highly suitable for medical applications as biocompatible and biodegradable implant materials. Magnesium has mechanical properties similar to bone, stimulates bone regeneration, is an essential non-toxic element for the human body and degrades completely within the body environment. In consequence, magnesium is a promising candidate as implant material for orthopaedic applications. Protocols using the guideline of current ISO standards should be carefully evaluated when applying them for the characterization of the cytotoxic potential of degradable magnesium materials. For as-cast material we recommend using 10 times more extraction medium than recommended by the ISO standards to obtain reasonable results for reliable cytotoxicity rankings of degradable materials in vitro. In addition primary isolated human osteoblasts or mesenchymal stem cells should be used to test magnesium materials.

  4. Reprint of: Improved cytotoxicity testing of magnesium materials

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Janine [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Department for Structural Research on Macromolecules, Max-Planck Str. 1, D - 21502 Geesthacht (Germany); Proefrock, Daniel [Helmholtz-Zentrum Geesthacht, Institute for Coastal Research, Department for Marine Bioanalytical Chemistry, Max-Planck Str. 1, D - 21502 Geesthacht (Germany); Hort, Norbert [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Department for Magnesium Processing, Max-Planck Str. 1, D - 21502 Geesthacht (Germany); Willumeit, Regine; Feyerabend, Frank [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Department for Structural Research on Macromolecules, Max-Planck Str. 1, D - 21502 Geesthacht (Germany)

    2011-12-15

    Metallic magnesium (Mg) and its alloys are highly suitable for medical applications as biocompatible and biodegradable implant materials. Magnesium has mechanical properties similar to bone, stimulates bone regeneration, is an essential non-toxic element for the human body and degrades completely within the body environment. In consequence, magnesium is a promising candidate as implant material for orthopaedic applications. Protocols using the guideline of current ISO standards should be carefully evaluated when applying them for the characterization of the cytotoxic potential of degradable magnesium materials. For as-cast material we recommend using 10 times more extraction medium than recommended by the ISO standards to obtain reasonable results for reliable cytotoxicity rankings of degradable materials in vitro. In addition primary isolated human osteoblasts or mesenchymal stem cells should be used to test magnesium materials.

  5. In vitro cytotoxicity of fungi spoiling maize silage

    DEFF Research Database (Denmark)

    Rasmussen, Rie Romme; Rasmussen, Peter Have; Larsen, Thomas Ostenfeld

    2011-01-01

    Penicillium roqueforti, Penicillium paneum, Monascus ruber, Alternaria tenuissima, Fusarium graminearum, Fusarium avenaceum, Byssochlamys nivea and Aspergillus fumigatus have previously been identified as major fungal contaminants of Danish maize silage. In the present study their metabolite....... roqueforti metabolites roquefortine C (48μg/mL), andrastin A (>50μg/mL), mycophenolic acid (>100μg/mL) and 1-hydroxyeremophil-7(11),9(10)-dien-8-one (>280μg/mL) were high. Fractionating of agar extracts identified PR-toxin as an important cytotoxic P. roqueforti metabolite, also detectable in maize silage....... The strongly cytotoxic B. nivea and P. paneum agar extracts contained patulin above the IC50 of 0.6μg/mL, however inoculated onto maize silage B. nivea and P. paneum did not produce patulin (>371μg/kg). Still B. nivea infected maize silage containing mycophenolic acid (∼50mg/kg), byssochlamic acid and other...

  6. Interconnection between thyroid hormone signalling pathways and parvovirus cytotoxic functions.

    Science.gov (United States)

    Vanacker, J M; Laudet, V; Adelmant, G; Stéhelin, D; Rommelaere, J

    1993-01-01

    Nonstructural (NS) proteins of autonomous parvoviruses can repress expression driven by heterologous promoters, an activity which thus far has not been separated from their cytotoxic effects. It is shown here that, in transient transfection assays, the NS-1 protein of the parvovirus minute virus of mice (MVMp) activates the promoter of the human c-erbA1 gene, encoding the thyroid hormone (T3) receptor alpha. The endogenous c-erbA1 promoter is also a target for induction upon MVMp infection. Moreover, T3 was found to up-modulate the level of cell sensitivity to parvovirus attack. These data suggest an interconnection between T3 signalling and NS cytotoxic pathways. Images PMID:8230488

  7. Cytotoxicity of extracts of spices to cultured cells.

    Science.gov (United States)

    Unnikrishnan, M C; Kuttan, R

    1988-01-01

    The cytotoxicity of the extracts from eight different spices used in the Indian diet was determined using Dalton's lymphoma ascites tumor cells and human lymphocytes in vitro and Chinese Hamster Ovary cells and Vero cells in tissue culture. Alcoholic extracts of the spices were found to be more cytotoxic to these cells than their aqueous extracts. Alcoholic extracts of several spices inhibited cell growth at concentrations of 0.2-1 mg/ml in vitro and 0.12-0.3 mg/ml in tissue culture. Ginger, pippali (native to India; also called dried catkins), pepper, and garlic showed the highest activity followed by asafetida, mustard, and horse-gram (native to India). These extracts also inhibited the thymidine uptake into DNA.

  8. In vitro bioactivity and cytotoxicity of chemically treated glass fibers

    Directory of Open Access Journals (Sweden)

    Ângela Leão Andrade

    2004-12-01

    Full Text Available Samples of a commercial glass fiber FM® (Fiber Max were used to test the efficacy of a chemical sol-gel surface treatment to enhance their bioactivity. After treatment with tetraethoxysilane (TEOS, individual fiber samples were soaked into a simulated body fluid (SBF solution, from which they were removed at intervals of 5 and 10 days. Micrographs obtained by scanning electron microscopy (SEM analysis of samples chemically treated with TEOS revealed the formation of a hydroxyapatite (HA coating layer after 5 days into SBF solution. Fourier transform infrared spectroscopic (FTIR analyses confirmed that the coating layer has P-O vibration bands characteristic of HA. The in vitro cytotoxicity was evaluated using a direct contact test, minimum essential medium elution test (ISO 10993-5 and MTT assay. Fibers immersed in SBF and their extracts exhibited lower cytotoxicity than the controls not subjected to immersion, suggesting that SBF treatment improves the biocompatibility of the fiber.

  9. Reducing ZnO nanoparticle cytotoxicity by surface modification.

    Science.gov (United States)

    Luo, Mingdeng; Shen, Cenchao; Feltis, Bryce N; Martin, Lisandra L; Hughes, Anthony E; Wright, Paul F A; Turney, Terence W

    2014-06-07

    Nanoparticulate zinc oxide (ZnO) is one of the most widely used engineered nanomaterials and its toxicology has gained considerable recent attention. A key aspect for controlling biological interactions at the nanoscale is understanding the relevant nanoparticle surface chemistry. In this study, we have determined the disposition of ZnO nanoparticles within human immune cells by measurement of total Zn, as well as the proportions of extra- and intracellular dissolved Zn as a function of dose and surface coating. From this mass balance, the intracellular soluble Zn levels showed little difference in regard to dose above a certain minimal level or to different surface coatings. PEGylation of ZnO NPs reduced their cytotoxicity as a result of decreased cellular uptake arising from a minimal protein corona. We conclude that the key role of the surface properties of ZnO NPs in controlling cytotoxicity is to regulate cellular nanoparticle uptake rather than altering either intracellular or extracellular Zn dissolution.

  10. Antimycobacterial and cytotoxicity activity of synthetic and natural compounds

    Directory of Open Access Journals (Sweden)

    Ana O. de Souza

    2007-01-01

    Full Text Available Antimycobacterial and cytotoxicity activity of synthetic and natural compounds. Secondary metabolites from Curvularia eragrostidis and Drechslera dematioidea, Clusia sp. floral resin, alkaloids from Pilocarpus alatus, salicylideneanilines, piperidine amides, the amine 1-cinnamylpiperazine and chiral pyridinium salts were assayed on Mycobacterium tuberculosis H37Rv. N-(salicylidene-2-hydroxyaniline was the most effective compound with a minimal inhibitory concentration (MIC of 8 µmol/L. Dihydrocurvularin was moderately effective with a MIC of 40 µmol/L. Clusia sp. floral resin and a gallocatechin-epigallocatechin mixture showed MIC of 0.02 g/L and 38 µmol/L, respectively. The cytotoxicity was evaluated for N-(salicylidene-2-hydroxyaniline, curvularin, dihydrocurvularin and Clusia sp. floral resin, and the selectivity indexes were > 125, 0.47, 0.75 and 5, respectively.

  11. In vitro cytotoxic activity of Brazilian Middle West plant extracts

    Directory of Open Access Journals (Sweden)

    Talal Suleiman Mahmoud

    2011-06-01

    Full Text Available Cytotoxic activity of eight plant extracts, native from the Mid-West of Brazil comprising Cerrado, Pantanal and semideciduous forest, was evaluated for MDA-MB-435, SF-295, and HCT-8 cancer cell strains. A single 100 µg.mL-1 dose of each extract was employed with 72 h of incubation for all tests. Doxorubicin (1 µg.mL-1 was used as the positive control and the MTT method was used to detect the activity. Cytotoxicity of distinct polarities was observed in thirty extracts (46%, from different parts of the following species: Tabebuia heptaphylla (Vell. Toledo, Bignoniaceae, Tapirira guianensis Aubl., Anacardiaceae, Myracrodruon urundeuva Allemão, Anacardiaceae, Schinus terebinthifolius Raddi, Anacardiaceae, Gomphrena elegans Mart., Amaranthaceae, Attalea phalerata Mart. ex Spreng., Arecaceae, Eugenia uniflora L., Myrtaceae, and Annona dioica A. St.-Hil., Annonaceae. Extracts of at least two tested cell strains were considered to be highly active since their inhibition rate was over 75%.

  12. Evaluation of cell cytotoxic effect on herbal extracts mixtures

    International Nuclear Information System (INIS)

    Kim, Yong Soo; Gwon, Hui Jeong; Choi, Bo Ram; Lim, Youn Mook; Nho, Young Chang

    2009-01-01

    Herbal extracts (HE) such as Houttuynia cordata Thunb., Eucommia ulimoides, Plantago asiatica var., Morus alba L., and Ulmus davidiana var., are known to suppress an atopic dermatitis like skin lesions. In this study, to evaluate the cell cytotoxicity effect on L929, HaCaT and HMC-1 cell by the HE, the herbs were extracted with distilled water (at 75 .deg. C) and then the HE mixtures were freeze-dried for 5 days and sterilized with γ-rays. The cytotoxicity was measured by Cell Counting Kit-8 (CCK-8) assay. The result showed that the HE mixtures did not significantly affect cell viability and had no toxicity on the cells. These findings indicate that the HE mixtures can be used as a potential therapeutic agent

  13. Evaluation of cell cytotoxic effect on herbal extracts mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Soo; Gwon, Hui Jeong; Choi, Bo Ram; Lim, Youn Mook; Nho, Young Chang [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2009-12-15

    Herbal extracts (HE) such as Houttuynia cordata Thunb., Eucommia ulimoides, Plantago asiatica var., Morus alba L., and Ulmus davidiana var., are known to suppress an atopic dermatitis like skin lesions. In this study, to evaluate the cell cytotoxicity effect on L929, HaCaT and HMC-1 cell by the HE, the herbs were extracted with distilled water (at 75 .deg. C) and then the HE mixtures were freeze-dried for 5 days and sterilized with {gamma}-rays. The cytotoxicity was measured by Cell Counting Kit-8 (CCK-8) assay. The result showed that the HE mixtures did not significantly affect cell viability and had no toxicity on the cells. These findings indicate that the HE mixtures can be used as a potential therapeutic agent.

  14. In vitro cytotoxicity of chemical preservatives on human fibroblast cells

    Directory of Open Access Journals (Sweden)

    Daniel Gonsales Spindola

    2018-05-01

    Full Text Available ABSTRACT Preservatives are widely used substances that are commonly added to various cosmetic and pharmaceutical products to prevent or inhibit microbial growth. In this study, we compared the in vitro cytotoxicity of different types of currently used preservatives, including methylparaben, imidazolidinyl urea (IMU, and sodium benzoate, using the human newborn fibroblast cell line CCD1072Sk. Of the tested preservatives, only IMU induced a reduction in cell viability, as shown using the MTT assay and propidium iodide staining (IMU>methylparaben>sodium benzoate. IMU was shown to promote homeostatic alterations potentially related to the initiation of programed cell death, such as decreased mitochondrial membrane potential and caspase-3 activation, in the treated cells. Methylparaben and sodium benzoate were shown to have a very low cytotoxic activity. Taken together, our results suggest that IMU induces programed cell death in human fibroblasts by a canonical intrinsic pathway via mitochondrial perturbation and subsequent release of proapoptotic factors.

  15. Preparation of Conjugates of Cytotoxic Lupane Triterpenes with Biotin.

    Science.gov (United States)

    Soural, Miroslav; Hodon, Jiri; Dickinson, Niall J; Sidova, Veronika; Gurska, Sona; Dzubak, Petr; Hajduch, Marian; Sarek, Jan; Urban, Milan

    2015-12-16

    To better understand the mechanism of action of antitumor triterpenes, we are developing methods to identify their molecular targets. A promising method is based on combination of quantitative proteomics with SILAC and uses active compounds anchored to magnetic beads via biotin-streptavidin interaction. We developed a simple and fast solid-phase synthetic technique to connect terpenes to biotin through a linker. Betulinic acid was biotinylated from three different conjugation sites for use as a standard validation tool since many molecular targets of this triterpene are already known. Then, a set of four other cytotoxic triterpenoids was biotinylated. Biotinylated terpenes were similarly cytotoxic to their nonbiotinylated parents, which suggests that the target identification should not be influenced by linker or biotin. The developed solid-phase synthetic approach is the first attempt to use solid-phase synthesis to connect active triterpenes to biotin and is applicable as a general procedure for routine conjugation of triterpenes with other molecules of choice.

  16. Myrtus comunis and Eucalyptus camaldulensis cytotoxicity on breast cancer cells

    Directory of Open Access Journals (Sweden)

    Hrubik Jelena D.

    2012-01-01

    Full Text Available In vitro cytotoxicity of methanol, ethyl acetate, n-buthanol, and water extracts of Myrtus communis L. and Eucalyptus camaldulensis Dehnh. was examined against two human breast cancer cell lines (MCF 7 and MDA-MB-231 using MTT and SRB assays. The results showed significant cytotoxic potential of examined extracts, with IC50 values ranging from 7 to 138 μg/ml for M. communis and 3-250 μg/ml for E. camaldulensis. The two plants generally expressed similar activity, and no significant difference in cell line’s sensitivity towards extracts was observed. The results indicate to M. communis and E. camaldulensis as candidates for thorough chemical analyses for identification of active compounds, and eventually for attention in the process of discovery of new natural products in the control of cancer. [Projekat Ministarstva nauke Republike Srbije, br. 173037 i br. 172058

  17. Cytotoxic Amides from Fruits of Kawakawa, Macropiper excelsum.

    Science.gov (United States)

    Lei, Jeremy; Burgess, Elaine J; Richardson, Alistair T B; Hawkins, Bill C; Baird, Sarah K; Smallfield, Bruce M; van Klink, John W; Perry, Nigel B

    2015-08-01

    Cytotoxic amides have been isolated from the fruits of the endemic New Zealand medicinal plant kawakawa, Macropiper excelsum (Piperaceae). The main amide was piperchabamide A and this is the first report of this rare compound outside the genus Piper. Eleven other amides were purified including two new compounds with the unusual 3,4-dihydro-1(2H)-pyridinyl group. The new compounds were fully characterized by 2D NMR spectroscopy, which showed a slow exchange between two rotamers about the amide bond, and they were chemically synthesized. In view of the antitumor activity of the related piperlongumine, all of these amides plus four synthetic analogs were tested for cytotoxicity. The most active was the piperine homolog piperdardine, with an IC50 of 14 µM against HT 29 colon cancer cells. Georg Thieme Verlag KG Stuttgart · New York.

  18. In vitro anthelmintic and cytotoxicity activities the Digitaria insularis (Poaceae).

    Science.gov (United States)

    Santos, Francianne Oliveira; de Lima, Hélimar Gonçalves; de Souza Santos, Nathália Silva; Serra, Taiane Menezes; Uzeda, Rosângela Soares; Reis, Isabella Mary Alves; Botura, Mariana Borges; Branco, Alexsandro; Batatinha, Maria José Moreira

    2017-10-15

    This study aimed to evaluate the in vitro activity of D. insularis extracts and fractions against gastrointestinal nematodes of goats and its cytotoxicity on Vero cells. The egg hatch (EHT) and larval motility (LMT) tests were conducted to investigate the anthelmintic effects of the crude hydroethanolic (CH), ethyl acetate (EA), butanolic (BT) and residual hydroethanolic (RH) extracts. The elution of the active extract (EA) on column chromatography (SiO 2 ) using organic solvents furnished six fractions (FR1 to FR6), which were also tested. Cytotoxicity was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Trypan Blue exclusion assays. All extracts, FR2 and FR3, inhibited egg hatching in a concentration-dependent manner. The EHT led to EC 50 values (effective concentration 50%) of 0.64; 0.69; 0.77; 0.96; 0.27 and 0.65mg/mL for CH, EA, BT, RH, FR2 and FR3, respectively. However, the extracts exhibited low effect on the motility of L 3. In the cytotoxicity evaluation (MTT assay), the IC 50 (inhibitory concentration 50%) was 1.18 (EA), 1.65 (FR2) and 1.59mg/mL (FR3), which was relatively high (low toxicity) in comparison to the EC 50 values in EHT, mainly for FR2. The chemical analyses of most active fractions (FR2) by Liquid Chromatography coupled to Mass Spectrometry (LC-MS) led the characterization of the flavones tricin and diosmetin. These results showed the high anthelmintic effect and low cytotoxicity of D. insularis and also that the flavones can be probably responsible for the nematocidal activity of this plant. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Phototoxicity and cytotoxicity of fullerol in human lens epithelial cells

    International Nuclear Information System (INIS)

    Roberts, Joan E.; Wielgus, Albert R.; Boyes, William K.; Andley, Usha; Chignell, Colin F.

    2008-01-01

    The water-soluble, hydroxylated fullerene [fullerol, nano-C 60 (OH) 22-26 ] has several clinical applications including use as a drug carrier to bypass the blood ocular barriers. We have assessed fullerol's potential ocular toxicity by measuring its cytotoxicity and phototoxicity induced by UVA and visible light in vitro with human lens epithelial cells (HLE B-3). Accumulation of nano-C 60 (OH) 22-26 in the cells was confirmed spectrophotometrically at 405 nm and cell viability estimated using MTS and LDH assays. Fullerol was cytotoxic to HLE B-3 cells maintained in the dark at concentrations higher than 20 μM. Exposure to either UVA or visible light in the presence of > 5 μM fullerol-induced phototoxic damage. When cells were pretreated with non-toxic antioxidants: 20 μM lutein, 1 mM N-acetyl cysteine, or 1 mM L-ascorbic acid prior to irradiation, only the singlet oxygen quencher-lutein significantly protected against fullerol photodamage. Apoptosis was observed in lens cells treated with fullerol whether or not the cells were irradiated, in the order UVA > visible light > dark. Dynamic light scattering (DLS) showed that in the presence of the endogenous lens protein α-crystallin, large aggregates of fullerol were reduced. In conclusion, fullerol is both cytotoxic and phototoxic to human lens epithelial cells. Although the acute toxicity of water-soluble nano-C 60 (OH) 22-26 is low, these compounds are retained in the body for long periods, raising concern for their chronic toxic effect. Before fullerols are used to deliver drugs to the eye, they should be tested for photo- and cytotoxicity in vivo

  20. Antioxidant and cytotoxicity effects of seed oils from edible fruits

    OpenAIRE

    Olubunmi Atolani; Joshua Omere; C.A. Otuechere; A. Adewuyi

    2012-01-01

    Objective: To propose a natural remedy for the some acute diseases the fatty acids profile, antioxidant and cytotoxicity potentials of seed oils from natural sources have been examined. Methods: The fatty acids profile of seed oils from sweet orange, grape, lime and watermelon obtained by soxhlet extraction were trans-esterified and examined by gas chromatography-mass spectrometry (GC-MS). The antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl assay were examined and compared with ga...

  1. A cytotoxic cyclic heptapeptide from the seeds of Annona cherimola.

    Science.gov (United States)

    Wélé, Alassane; Zhang, Yanjun; Ndoye, Idrissa; Brouard, Jean-Paul; Pousset, Jean-Louis; Bodo, Bernard

    2004-09-01

    From a methanol extract of the seeds of Annona cherimola, a new cyclic heptapeptide, cherimolacyclopeptide C, has been isolated. The structure was elucidated on the basis of the MS/MS fragmentation using a Q-TOF mass spectrometer equipped with an ESI source, extensive 2D NMR experiments, and chemical degradation. Cherimolacyclopeptide C exhibited significant in vitro cytotoxic activity against KB cells, with an IC(50) value of 0.072 microM.

  2. Cytotoxic Natural Products from Marine Sponge-Derived Microorganisms

    Directory of Open Access Journals (Sweden)

    Huawei Zhang

    2017-03-01

    Full Text Available A growing body of evidence indicates that marine sponge-derived microbes possess the potential ability to make prolific natural products with therapeutic effects. This review for the first time provides a comprehensive overview of new cytotoxic agents from these marine microbes over the last 62 years from 1955 to 2016, which are assorted into seven types: terpenes, alkaloids, peptides, aromatics, lactones, steroids, and miscellaneous compounds.

  3. Colloidal polyaniline dispersions: Antibacterial activity, cytotoxicity and neutrophil oxidative burst

    Czech Academy of Sciences Publication Activity Database

    Kuceková, Z.; Humpolíček, P.; Kašpárková, V.; Perečko, Tomáš; Lehocký, M.; Hauerlandova, I.; Saha, P.; Stejskal, Jaroslav

    Roč. 116, APR 2014 ( 2014 ), s. 411-417 ISSN 0927-7765 R&D Projects: GA ČR(CZ) GA13-08944S; GA MŠk(CZ) EE2.3.30.0030 Institutional support: RVO:68081707 ; RVO:61389013 Keywords : Cytotoxicity * Apoptosis * Necrosis Subject RIV: BO - Biophysics; CD - Macromolecular Chemistry (UMCH-V) Impact factor: 4.152, year: 2014

  4. Toxin content and cytotoxicity of algal dietary supplements

    Energy Technology Data Exchange (ETDEWEB)

    Heussner, A.H.; Mazija, L. [Human and Environmental Toxicology, University of Konstanz, 78457 Konstanz (Germany); Fastner, J. [Federal Environmental Agency, Section II 3.3—Drinking-water resources and treatment, Berlin (Germany); Dietrich, D.R., E-mail: daniel.dietrich@uni-konstanz.de [Human and Environmental Toxicology, University of Konstanz, 78457 Konstanz (Germany)

    2012-12-01

    Blue-green algae (Spirulina sp., Aphanizomenon flos-aquae) and Chlorella sp. are commercially distributed as organic algae dietary supplements. Cyanobacterial dietary products in particular have raised serious concerns, as they appeared to be contaminated with toxins e.g. microcystins (MCs) and consumers repeatedly reported adverse health effects following consumption of these products. The aim of this study was to determine the toxin contamination and the in vitro cytotoxicity of algae dietary supplement products marketed in Germany. In thirteen products consisting of Aph. flos-aquae, Spirulina and Chlorella or mixtures thereof, MCs, nodularins, saxitoxins, anatoxin-a and cylindrospermopsin were analyzed. Five products tested in an earlier market study were re-analyzed for comparison. Product samples were extracted and analyzed for cytotoxicity in A549 cells as well as for toxin levels by (1) phosphatase inhibition assay (PPIA), (2) Adda-ELISA and (3) LC–MS/MS. In addition, all samples were analyzed by PCR for the presence of the mcyE gene, a part of the microcystin and nodularin synthetase gene cluster. Only Aph. flos-aquae products were tested positive for MCs as well as the presence of mcyE. The contamination levels of the MC-positive samples were ≤ 1 μg MC-LR equivalents g{sup −1} dw. None of the other toxins were found in any of the products. However, extracts from all products were cytotoxic. In light of the findings, the distribution and commercial sale of Aph. flos-aquae products, whether pure or mixed formulations, for human consumption appear highly questionable. -- Highlights: ► Marketed algae dietary supplements were analyzed for toxins. ► Methods: Phosphatase inhibition assay (PPIA), Adda-ELISA, LC-MS/MS. ► Aph. flos-aquae products all tested positive for microcystins. ► Products tested negative for nodularins, saxitoxins, anatoxin-a, cylindrospermopsin. ► Extracts from all products were cytotoxic.

  5. The relevancy of controlled nanocrystallization on rifampicin characteristics and cytotoxicity

    Directory of Open Access Journals (Sweden)

    Mohyeldin SM

    2016-05-01

    Full Text Available Salma M Mohyeldin, Mohammed M Mehanna, Nazik A Elgindy Department of Industrial Pharmacy, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt Purpose: This article investigated the influence of novel rifampicin nanosuspension (RIF NS for enhancing drug delivery properties. Methods: RIF NS was fabricated using the antisolvent precipitation technique. The impact of solvent type and flow rate, stabilizer type and concentration, and stirring time and apparatus together with the solvent–antisolvent volume ratio on its controlled nanocrystallization has been evaluated. NSs were characterized by transmission electron microscopy, particle size and zeta potential analysis, solubility, and dissolution profiles. The compatibility between RIF and the stabilizer was investigated via Fourier transform infrared spectroscopy and the differential scanning calorimetry techniques. The shelf-life stability of the RIF NS was assessed within a period of 3 months at different storage temperatures. Cell cytotoxicity was evaluated using 3(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay on lung epithelial cells. Results: Polyvinyl alcohol at 0.4% w/v, 1:15 methanol to deionized water volume ratio and 30-minutes sonication were the optimal parameters for RIF NS preparation. Nanocrystals were obtained with a nanometeric particle size (101 nm and a negative zeta potential (-26 mV. NS exhibited a 50-fold enhancement in RIF solubility and 97% of RIF was dissolved after 10 minutes. The RIF NS was stable at 4±0.5°C with no significant change in particle size or zeta potential. The MTT cytotoxicity assay of RIF NS demonstrated a good safety profile and reduction in cell cytotoxicity with half maximal inhibitory concentration values of 0.5 and 0.8 mg/mL for free RIF and RIF NS, respectively. Conclusion: A novel RIF NS could be followed as an approach for enhancing RIF physicochemical characteristics with a prominence of a safer and better drug

  6. Antimycobacterial, antioxidant and cytotoxic activities of essential oil ...

    African Journals Online (AJOL)

    mL and 495.6 - >2000μg/mL for DPPH and ABTS assay respectively. The cytotoxicity assay showed LC50 ranged between 26.47 to 93.64 μg/mL against Vero cells and 74.29 to 225.40 μg/mL against C3A. The results of this study show that the ...

  7. In vitro cytotoxicity of biosynthesized titanium dioxide nanoparticles ...

    African Journals Online (AJOL)

    ISSN: 1596-5996 (print); 1596-9827 (electronic) ... dioxide (Ti(OH)2) (80 mL) in aqueous solution with stirring for 2 h at room temperature. The TiO2 NPs ... The TiO2 NPs showed dose-dependent cytotoxicity towards D145 cells. Keywords: .... with ethanol and chloroform, and dried at room ... oxidation state of the TiO2 NPs.

  8. CYTOTOXIC AND ANTIOXIDANT ACTIVITY OF BUCKWHEAT HULL EXTRACTS

    Directory of Open Access Journals (Sweden)

    Martina Danihelová

    2013-02-01

    Full Text Available Buckwheat contains many prophylactic compounds that are concentrated mainly in outer layers of buckwheat grain. The aim of this study was to prepare buckwheat hull extracts. Ten buckwheat cultivars were screened for their antioxidant and anticancer properties. Total polyphenol content was determined using Folin-Ciocalteau's reagent. Antioxidant activity was established by the method of binding free radical DPPH. Cytotoxic properties were measured on human cervical cancer cells HeLa using mitochondrial cytotoxic test (MTT. Total polyphenol content ranged from 166.67 to 635.31 mg GAE/100 g DW. The highest content displayed tartary buckwheat cultivar Madawaska (0.64% of hulls weight. Among common buckwheat the richest in polyphenols were cultivars Bamby and KASHO-2. The best free radical binding antioxidant activity was found for cultivars with highest polyphenol content. This relationship was not observed for cytotoxic action on human cervical cancer cells. The best growth inhibitory activity on HeLa cancer cells displayed common buckwheat cultivars Bamby and KASHO-2 (up to 50%, extract concentration 100 µg/ml. This was not found for tartary buckwheat cultivar Madawaska.

  9. A Cytotoxic Hydroperoxy Sterol from the Brown Alga, Nizamuddinia Zanardinii

    Directory of Open Access Journals (Sweden)

    Abdolhossein Rustaiyan

    2013-03-01

    Full Text Available Background:The marine environment is a unique source of bioactive natural products, of which Nizamuddinia zanardinii is an important brown algae distributed in Oman Sea. Literature revealed that there is no report on phytochemistry and pharmacology of this valuable algae.Methods:Bioguided fractionation of the methanolic extract of Nizamuddinia zanardinii, collected from Oman Sea, led to the isolation of a hydroperoxy sterol. Its structure was determined by analysis of the spectroscopic data as 24-hydroperoxy-24-vinyl cholesterol (HVC. In vitro cytotoxic activity of this compound was evaluated against HT29, MCF7, A549, HepG2 and MDBK cell lines.Results:Although 24(R-hydroproxy-24-vinylcholesterol has been previously reported from Sargassum and Padina species, it is the first report on the presence of this compound from N. zanardinii. This compound exhibited cytotoxicity in all cell lines (IC50, 3.62, 9.09, 17.96, 32.31 and 37.31 μg/mL respectively. HVC was also evaluated for apoptotic activity and demonstrated positive results in terminal deoxynucleotidyl transferase dUTP Nick End labeling (TUNEL assay suggesting it a candidate for further apoptotic studies.Conclusions:Nizamuddinia zanardinii, a remarkable brown algae of Oman Sea, is a good source of hydroproxy sterols with promising cytotoxic on various cell lines particularly human colon adenocarcinoma.

  10. Cytotoxicity of graphene: recent advances and future perspective.

    Science.gov (United States)

    Zhou, Ruhong; Gao, Huajian

    2014-01-01

    Graphene, a unique two-dimensional single-atom-thin nanomaterial with exceptional structural, mechanical, and electronic properties, has spurred an enormous interest in many fields, including biomedical applications, which at the same time ignites a growing concern on its biosafety and potential cytotoxicity to human and animal cells. In this review, we present a summary of some very recent studies on this important subject with both experimental and theoretical approaches. The molecular interactions of graphene with proteins, DNAs, and cell membranes (both bacteria and mammalian cells) are discussed in detail. Severe distortions in structures and functions of these biomacromolecules by graphene are identified and characterized. For example, the graphene is shown to disrupt bacteria cell membranes by insertion/cutting as well as destructive extraction of lipid molecules directly. More interestingly, this cytotoxicity has been shown to have implications in de novo design of nanomedicine, such as graphene-based band-aid, a potential 'green' antibiotics due to its strong physical-based (instead of chemical-based) antibacterial capability. These studies have provided a better understanding of graphene nanotoxicity at both cellular and molecular levels, and also suggested therapeutic potential by using graphene's cytotoxicity against bacteria cells. © 2014 Wiley Periodicals, Inc.

  11. In vitro cytotoxic screening of selected Saudi medicinal plants.

    Science.gov (United States)

    Almehdar, Hussein; Abdallah, Hossam M; Osman, Abdel-Moneim M; Abdel-Sattar, Essam A

    2012-04-01

    Many natural products from plants have been identified to exert anticancer activity. It might be expected to be a challenge to look at the Saudi plants in order to discover new sources for new molecules which may have anticancer activity. The methanolic extracts of forty species of plants traditionally used in Saudi Arabia for the treatment of a variety of diseases were tested in vitro for their potential anticancer activity on different human cancer cell lines. The cytotoxic activity of the methanolic extracts of the tested plants were determined using three human cancer cell lines, namely, breast cancer (MCF7), hepatocellular carcinoma (HEPG2), and cervix cancer (HELA) cells. In addition, human normal melanocyte (HFB4) was used as normal nonmalignant cells. Sulforhodamine B colorimetric assay was used to evaluate the in vitro cytotoxic activity of the different extracts. The growth inhibition of 50% (IC(50)) for each extract was calculated from the optical density of treated and untreated cells. Doxorubicin, a broad-spectrum anticancer drug, was used as the positive control. Nine plant extracts were chosen for further fractionation based on their activity and availability. Interesting cytotoxic activity was observed for Hypoestes forskaolii, Withania somnifera, Solanum glabratum, Adenium obesum, Pistacia vera oleoresin, Caralluma quadrangula, Eulophia petersii, Phragmanthera austroarabica, and Asparagus officinalis. Other extracts showed poor activity.

  12. Antimicrobial and cytotoxic potentials of Buddleja polystachya extracts

    Directory of Open Access Journals (Sweden)

    Ghada Ahmed Fawzy

    2013-06-01

    Full Text Available Most of the species of Buddleja have found applications in folk medicine. This study aimed to evaluate the in vitro antimicrobial and cytotoxic potentials of B. polystachya extracts. Four extracts were prepared A-D (dichloromethane, ethyl acetate, n-butanol, and aqueous extracts, respectively. The antimicrobial activity was evaluated using the broth micro-dilution assay for minimum inhibitory concentrations (MIC. The crystal violet staining method (CVS was used for the evaluation of the cytotoxic activity on HepG-2, MCF-7 and HCT-116 human cell lines. Results showed that the highest antimicrobial activity was given by the ethyl acetate extract followed by the dichloromethane extract, while the n-butanol revealed moderate activity against gram positive bacteria only with no activity against the rest of tested microorganisms. The aqueous extract was totally ineffective against all tested microorganisms at 20 mg/ml. Among the four extracts tested, dichloromethane and ethyl acetate extracts showed the highest cytotoxic activity on all three human cell lines.

  13. Cytotoxic Activity of Coagulase-Negative Staphylococci in Bovine Mastitis

    Science.gov (United States)

    Zhang, Songlin; Maddox, Carol W.

    2000-01-01

    Secreted toxins play important roles in the pathogenesis of bacterial infections. In this study, we examined the presence of secreted cytotoxic factors of coagulase-negative staphylococci (CoNS) from bovine clinical and subclinical mastitis. A 34- to 36-kDa protein with cell-rounding cytotoxic activity was found in many CoNS strains, especially in Staphylococcus chromogenes strains. The protein caused cell detachment and cell rounding in several cell lines, including HEp-2, Int 407, CHO-K1, and Y-1 cells. Native protein recovered from nondenatured polyacrylamide gel electrophoresis showed both cytotoxic activity and casein hydrolysis activity. The purified protein had a pH optimal at 7.2 to 7.5 and a pI of 5.1 and was heat labile. The proteolytic activity could be inhibited by zinc and metal specific inhibitors such as 1,10-phenanthroline and EDTA, indicating that it is a metalloprotease. Protein mass analysis and peptide sequencing indicated that the protein is a novel metalloprotease. Different bacterial strains expressed variable levels of 34- to 36-kDa protease, which may provide an indication of strain virulence. PMID:10678913

  14. Cytotoxicity of cardenolides and cardenolide glycosides from Asclepias curassavica.

    Science.gov (United States)

    Li, Jun-Zhu; Qing, Chen; Chen, Chang-Xiang; Hao, Xiao-Jiang; Liu, Hai-Yang

    2009-04-01

    A new cardenolide, 12beta,14beta-dihydroxy-3beta,19-epoxy-3alpha-methoxy-5alpha-card-20(22)-enolide (6), and a new doubly linked cardenolide glycoside, 12beta-hydroxycalotropin (13), together with eleven known compounds, coroglaucigenin (1), 12beta-hydroxycoroglaucigenin (2), calotropagenin (3), desglucouzarin (4), 6'-O-feruloyl-desglucouzarin (5), calotropin (7), uscharidin (8), asclepin (9), 16alpha-hydroxyasclepin (10), 16alpha-acetoxycalotropin (11), and 16alpha-acetoxyasclepin (12), were isolated from the aerial part of ornamental milkweed, Asclepias curassavica and chemically elucidated through spectral analyses. All the isolates were evaluated for their cytotoxic activity against HepG2 and Raji cell lines. The results showed that asclepin (9) had the strongest cytotoxic activity with an IC(50) value of 0.02 microM against the two cancer cell lines and the new compound 13 had significant cytotoxic activity with IC(50) values of 0.69 and 1.46 microM, respectively.

  15. Immunomodulatory Effect of Rhaphidophora korthalsii on Natural Killer Cell Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Swee Keong Yeap

    2012-01-01

    Full Text Available The in vivo immunomodulatory effect of ethanolic extracts from leaves of Rhaphidophora korthalsii was determined via immune cell proliferation, T/NK cell phenotyping, and splenocyte cytotoxicity of BALB/c mice after 5 consecutive days of i.p. administration at various concentrations. Splenocyte proliferation index, cytotoxicity, peripheral blood T/NK cell population, and plasma cytokine (IL-2 and IFN-γ in mice were assessed on day 5 and day 15. High concentration of extract (350 μg/mice/day for 5 consecutive days was able to stimulate immune cell proliferation, peripheral blood NK cell population, IL-2, and IFN- γ cytokines, as well as splenocyte cytotoxicity against Yac-1 cell line. Unlike rIL-2 which degraded rapidly, the stimulatory effect from the extract managed to last until day 15. These results suggested the potential of this extract as an alternative immunostimulator, and they encourage further study on guided fractionation and purification to identify the active ingredients that contribute to this in vitro and in vivo immunomodulatory activity.

  16. Antimicrobial, Cytotoxic, Phytotoxic and Antioxidant Potential of Heliotropium strigosum Willd.

    Science.gov (United States)

    Khurm, Muhammad; Chaudhry, Bashir A; Uzair, Muhammad; Janbaz, Khalid H

    2016-07-28

    Background: Heliotropium strigosum Willd. (Chitiphal) is a medicinally important herb that belongs to the Boraginaceae family. Traditionally, this plant was used in the medication therapy of various ailments in different populations of the world. The aim of the study is to probe the therapeutic aspects of H. strigosum described in the traditional folklore history of medicines. Methods: In the present study, the dichloromethane crude extract of this plant was screened to explore the antimicrobial, cytotoxic, phytotoxic and antioxidant potential of H. strigosum . For antibacterial, antifungal and antioxidant activities, microplate alamar blue assay (MABA), agar tube dilution method and diphenyl picryl hydrazine (DPPH) radical-scavenging assay were used, respectively. The cytotoxic and phytotoxic potential were demonstrated by using brine shrimp lethality bioassay and Lemna minor assay. Results: The crude extract displayed positive cytotoxic activity in the brine shrimp lethality assay, with 23 of 30 shrimps dying at the concentration of 1000 µg/mL. It also showed moderate phytotoxic potential with percent inhibition of 50% at the concentration of 1000 µg/mL. The crude extract exhibited no significant antibacterial activity against Staphylococcus aureus , Shigella flexneri , Escherichia coli and Pseudomonas aeruginosa . Non-significant antifungal and radical scavenging activity was also shown by the dichloromethane crude extract. Conclusion: It is recommended that scientists focus on the identification and isolation of beneficial bioactive constituents with the help of advanced scientific methodologies that seems to be helpful in the synthesis of new therapeutic agents of desired interest.

  17. Development and cytotoxicity evaluation of SiAlONs ceramics

    International Nuclear Information System (INIS)

    Santos, C.; Ribeiro, S.; Daguano, J.K.M.F.; Rogero, S.O.; Strecker, K.; Silva, C.R.M.

    2007-01-01

    SiAlONs are ceramics with high potential as biomaterials due to their chemical stability, associated with suitable mechanical properties, such as high fracture toughness and fracture resistance. The objective of this work was to investigate the mechanical properties and the cytotoxicity of these ceramic materials. Three different compositions were prepared, using silicon nitride, aluminum nitride and a rare earth oxide mixture as starting powders, yielding Si 3 N 4 -SiAlON composites or pure SiAlON ceramics, after hot-pressing at 1750 deg. C, for 30 min. The sintered samples were characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). Furthermore, hardness and fracture toughness were determined using the Vicker's indentation method. The biological compatibility was evaluated by in vitro cytotoxicity tests. Ceramic with elevated hardness, ranging between 17 and 21 GPa, and high fracture toughness of 5 to 6 MPa m 1/2 were obtained. Since a nontoxic behavior was observed in the cytotoxicity tests, it may be assumed that SiAlON-based ceramics are viable materials for clinical applications

  18. Cytotoxic Flavones from the Stem Bark of Bougainvillea spectabilis Willd.

    Science.gov (United States)

    Do, Lien T M; Aree, Thammarat; Siripong, Pongpun; Vo, Nga T; Nguyen, Tuyet T A; Nguyen, Phung K P; Tip-Pyang, Santi

    2018-01-01

    Five new flavones possessing a fully substituted A-ring with C-6 and C-8 methyl groups, bougainvinones I - M (1: -5: ), along with three known congeners, 2'-hydroxydemethoxymatteucinol (6: ), 5,7,3',4'-tetrahydroxy-3-methoxy-6,8-dimethylflavone (7: ) and 5,7,4'-trihydroxy-3-methoxy-6,8-dimethylflavone (8: ), were isolated from the EtOAc extract of the stem bark of Bougainvillea spectabilis . Their structures were established by means of spectroscopic data (ultraviolet, infrared, high-resolution electrospray ionization mass spectrometry, and one-dimensional and two-dimensional nuclear magnetic resonance) and single-crystal X-ray crystallographic analysis. The in vitro cytotoxicity of all isolated compounds against five cancer cell lines (KB, HeLa S-3, MCF-7, HT-29, and HepG2) was evaluated. Compound 5: showed promising cytotoxic activity against the KB and HeLa S-3 cell lines, with IC 50 values of 7.44 and 6.68 µM. The other compounds exhibited moderate cytotoxicity against the KB cell line. Georg Thieme Verlag KG Stuttgart · New York.

  19. Cytotoxicity of titanium dioxide nanoparticles in mouse fibroblast cells.

    Science.gov (United States)

    Jin, Cheng-Yu; Zhu, Bang-Shang; Wang, Xue-Feng; Lu, Qing-Hua

    2008-09-01

    Nanotitanium dioxide (TiO2) is an important industrial material that is widely used as an additive in cosmetics, pharmaceuticals, and food colorants. Although the small size of the TiO2 nanoparticle is useful in various applications, the biosafety of this material needs to be evaluated. In this study, mouse fibroblast (L929) cells were used to evaluate the cytotoxicity of different concentrations (3-600 microg/mL) of homogeneous and weakly aggregated TiO2 nanoparticles in aqueous solution. The L929 cells became round and even shrank as the concentration of TiO2 nanoparticles increased. Moreover, TiO2 nanoparticle-treated cells had condensed fragmented chromatin or were directly necrosed, as observed by acridine orange (AO) staining. The transmission electron microscopy (TEM) analysis showed that in cells cultured in a medium containing 300 microg/mL TiO2, the number of lysosomes increased, and some cytoplasmic organelles were damaged. In addition, there was a significant increase in oxidative stress at higher TiO2 nanoparticle concentrations (>60 microg/mL). As the concentration of TiO2 nanoparticles increased in the culture medium, the levels of reactive oxygen species (ROS) and lactate dehydrogenase (LDH) increased, while those of methyl tetrazolium cytotoxicity (MTT), glutathione (GSH), and superoxide dismutase (SOD) decreased. A possible mechanism for the cytotoxicity of TiO2 nanoparticles is also discussed.

  20. Modification of the cytotoxic activity of mitomycin C

    International Nuclear Information System (INIS)

    Marshall, R.S.; Rauth, A.M.

    1985-01-01

    Utilizing a system in which oxygen levels could be altered and monitored during acute drug exposures, the authors have begun to characterize the cellular and molecular damage produced by MMC in CHO cells. The cytotoxic activity of MMC decreases sharply from 0 to 0.1% oxygen in solution, while from 0.1 to 20.0% there is little change. DNA crosslinking in cells was examined under these conditions by alkaline elution and found to be directly correlated with cell killing. While hypoxia increased crosslinking, significant levels were still observed under aerobic conditions. A cell-free assay for alkylation confirmed that overall levels increase in the absence of oxygen; however, negligible alkylation was observed under aerobic conditions. It was also noted that ascorbic acid present in the exposure medium (0.284 mM) increased the aerobic cytotoxicity without altering the hypoxic cytotoxicity. The present data suggest that MMC can be activated to an alkylating species by two mechanisms, one oxygen sensitive and one oxygen insensitive and that these two mechanisms may be independently modified