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Sample records for antibody-dependent cell-mediated cytotoxicity

  1. Enhancement of antibody-dependent cell mediated cytotoxicity: a new era in cancer treatment

    Directory of Open Access Journals (Sweden)

    Rajasekaran N

    2015-05-01

    Full Text Available Narendiran Rajasekaran,1,* Cariad Chester,1,* Atsushi Yonezawa,1,2 Xing Zhao,1,3 Holbrook E Kohrt1 1Division of Oncology, Stanford School of Medicine, Stanford University, Stanford, CA, USA; 2Department of Clinical Pharmacology and Therapeutics, Kyoto University Hospital, Kyoto, Japan; 3Tissue Engineering and Stem Cells Research Center, Department of Immunology, Guiyang Medical University, Guiyang, Guizhou Province, People's Republic of China *These authors contributed equally to this work Abstract: The therapeutic efficacy of some anti-tumor monoclonal antibodies (mAbs depends on the capacity of the mAb to recognize the tumor-associated antigen and induce cytotoxicity via a network of immune effector cells. This process of antibody-dependent cell-mediated cytotoxicity (ADCC against tumor cells is triggered by the interaction of the fragment crystallizable (Fc portion of the mAb with the Fc receptors on effector cells like natural killer cells, macrophages, γδ T cells, and dendritic cells. By augmenting ADCC, the antitumor activity of mAbs can be significantly increased. Currently, identifying and developing therapeutic agents that enhance ADCC is a growing area of research. Combining existing tumor-targeting mAbs and ADCC-promoting agents that stimulate effector cells will translate to greater clinical responses. In this review, we discuss strategies for enhancing ADCC and emphasize the potential of combination treatments that include US Food and Drug Administration-approved mAbs and immunostimulatory therapeutics. Keywords: ADCC, NK cell, reovirus, TLR, CD137

  2. Antigenic specificity of antibody-dependent cell-mediated cytotoxicity directed against human immunodeficiency virus in antibody-positive sera.

    OpenAIRE

    Koup, R A; Sullivan, J L; Levine, P H; Brewster, F; Mahr, A; Mazzara, G; McKenzie, S; Panicali, D

    1989-01-01

    Antibody-dependent cell-mediated cytotoxicity (ADCC) specific for human immunodeficiency virus (HIV) has been described for HIV-infected individuals. To determine the antigenic specificity of this immune response and to define its relationship to the disease state, an ADCC assay was developed using Epstein-Barr virus-transformed lymphoblastoid cell line targets infected with vaccinia virus vectors expressing HIV proteins. The vaccinia virus vectors induced appropriate HIV proteins (envelope g...

  3. Studies on ADCC (antibody-dependent cell-mediated cytotoxicity) using sheep red blood cells as target cells, 2

    International Nuclear Information System (INIS)

    Ichikawa, Yukinobu; Takaya, Masatoshi; Arimori, Shigeru

    1979-01-01

    A non-specific cytotoxic mediator from effector cells (human peripheral blood leukocytes) was investigated in the ADCC (antibody-dependent cell-mediated cytotoxicity) system using antibody-coated sheep red blood cells (SRBC) as target cells. 51 Cr-labelled homologous (sheep) or heterologous (human) red blood cells were used as adjacent cells. Either crude lymphocyte fraction, phagocyte depleted fraction or granulocyte rich fraction separated from human peripheral leukocytes showed moderate cytotoxic effect on homologous adjacent cells, however no cytotoxic activity on heterologous adjacent cells was demonstrated in any leukocyte fraction. This suggests that the cytotoxic effects on homologous adjacent cells were resulted from the translocation of antibody molecules to adjacent cells from antibody-coated target cells. We concluded that the cytotoxic mechanism in this ADCC system was not mediated by non-specific soluble factors released from either human peripheral lymphocytes, monocytes or granulocytes. (author)

  4. Comparison of Antibody-Dependent Cell-Mediated Cytotoxicity and Virus Neutralization by HIV-1 Env-Specific Monoclonal Antibodies.

    Science.gov (United States)

    von Bredow, Benjamin; Arias, Juan F; Heyer, Lisa N; Moldt, Brian; Le, Khoa; Robinson, James E; Zolla-Pazner, Susan; Burton, Dennis R; Evans, David T

    2016-07-01

    Although antibodies to the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein have been studied extensively for their ability to block viral infectivity, little data are currently available on nonneutralizing functions of these antibodies, such as their ability to eliminate virus-infected cells by antibody-dependent cell-mediated cytotoxicity (ADCC). HIV-1 Env-specific antibodies of diverse specificities, including potent broadly neutralizing and nonneutralizing antibodies, were therefore tested for ADCC against cells infected with a lab-adapted HIV-1 isolate (HIV-1NL4-3), a primary HIV-1 isolate (HIV-1JR-FL), and a simian-human immunodeficiency virus (SHIV) adapted for pathogenic infection of rhesus macaques (SHIVAD8-EO). In accordance with the sensitivity of these viruses to neutralization, HIV-1NL4-3-infected cells were considerably more sensitive to ADCC, both in terms of the number of antibodies and magnitude of responses, than cells infected with HIV-1JR-FL or SHIVAD8-EO ADCC activity generally correlated with antibody binding to Env on the surfaces of virus-infected cells and with viral neutralization; however, neutralization was not always predictive of ADCC, as instances of ADCC in the absence of detectable neutralization, and vice versa, were observed. These results reveal incomplete overlap in the specificities of antibodies that mediate these antiviral activities and provide insights into the relationship between ADCC and neutralization important for the development of antibody-based vaccines and therapies for combating HIV-1 infection. This study provides fundamental insights into the relationship between antibody-dependent cell-mediated cytotoxicity (ADCC) and virus neutralization that may help to guide the development of antibody-based vaccines and immunotherapies for the prevention and treatment of HIV-1 infection. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  5. Ocaratuzumab, an Fc-engineered antibody demonstrates enhanced antibody-dependent cell-mediated cytotoxicity in chronic lymphocytic leukemia.

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    Cheney, Carolyn M; Stephens, Deborah M; Mo, Xiaokui; Rafiq, Sarwish; Butchar, Jonathan; Flynn, Joseph M; Jones, Jeffrey A; Maddocks, Kami; O'Reilly, Adrienne; Ramachandran, Abhijit; Tridandapani, Susheela; Muthusamy, Natarajan; Byrd, John C

    2014-01-01

    Chronic lymphocytic leukemia (CLL) is common in both developed and developing nations where the need for inexpensive and convenient administration of therapy is apparent. Ocaratuzumab is a novel Fc-engineered humanized IgG1 anti-CD20 monoclonal antibody (mAb) designed for effective antibody-dependent cell-mediated cytotoxicity (ADCC) at very low concentrations that may facilitate sub-cutaneous (vs. intravenous) dosing. Here, we report ocaratuzumab's potency against CLL cells. In vitro assessment of ocaratuzumab's direct cytotoxicity (DC), complement-dependent cytotoxicity (CDC), antibody-dependent cellular phagocytosis (ADCP), and ADCC was performed on CLL cells. Ocaratuzumab induced DC, CDC, and ADCP similarly to rituximab or ofatumumab (anti-CD20 mAbs). However, ocaratuzumab showed an advantage in NK cell-mediated ADCC over these antibodies. In allogeneic ADCC, [E:T (effector:target) ratios = 25:1, 12:1, 6:1], ocaratuzumab (10 µg/mL) improved ADCC by ~3-fold compared with rituximab or ofatumumab (P<0.001 all tested E:T ratios). Notably, the superiority of ocaratuzumab-induced ADCC was observed at low concentrations (0.1-10 ug/ml; P<0.03; allogeneic assays). In extended allogeneic ADCC E:T titration, ocaratuzumab (0.1 µg/mL) demonstrated 19.4% more cytotoxicity than rituximab (E:T = 0.38:1; P = 0.0066) and 21.5% more cytotoxicity than ofatumumab (E:T = 1.5:1; P = 0.0015). In autologous ADCC, ocaratuzumab (10 µg/mL) demonstrated ~1.5-fold increase in cytotoxicity compared with rituximab or ofatumumab at all E:T ratios tested (E:Ts = 25:1,12:1,6:1; all P<0.001). Obinutuzumab, a glyco-engineered anti-CD20 mAb, showed no improvement in ADCC activity compared with ocaratuzumab. The enhanced ADCC of ocaratuzumab suggests that it may be effective at low concentrations. If supported by clinical investigation, this feature could potentially allow for subcutaneous dosing at low doses that could expand the potential of administering chemoimmunotherapy in developing

  6. Antibody-dependent cell-mediated cytotoxicity can be induced by MUC1 peptide vaccination of breast cancer patients.

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    Snijdewint, F G; von Mensdorff-Pouilly, S; Karuntu-Wanamarta, A H; Verstraeten, A A; Livingston, P O; Hilgers, J; Kenemans, P

    2001-07-01

    Human polymorphic epithelial mucin (PEM, MUC1) is a high molecular weight transmembrane glycoprotein expressed on the apical cell surface of glandular epithelium and is over-expressed and hypo-glycosylated in adenocarcinomas. The extracellular part of the molecule consists mainly of a variable number of 20 amino acid repeats that contain cryptic epitopes exposed in malignancy. The objective of our study was to determine whether humanized MUC1 MAbs and Abs induced by vaccination of breast cancer patients with MUC1 peptides can effect an antibody-dependent cell-mediated cytotoxicity (ADCC). An in vitro assay has been set up in which the breast tumor cell line ZR-75-1 is used as target and PBMC of healthy donors as effector cells. Different target and effector cells, as well as various MUC1 MAbs were tested to optimize the efficacy of the in vitro assay. The humanized MAb HuHMFG-1, which recognizes the PDTR sequence in the MUC1 tandem repeat, induced a strong cell-mediated cytotoxicity. Nine MUC1-expressing tumor cell lines, including 3 bone marrow-derived cell lines, as well as 2 MUC1-transfected cell lines were susceptible to different extent to MUC1 Ab-dependent killing. Large variations in the killing capacity of PBMC from healthy donors were found. The NK cells were the essential effector cells for the MUC1 Ab-dependent killing. Plasma samples with induced high levels of MUC1 Ab were obtained from breast cancer patients repeatedly immunized with a KLH-conjugated 33-mer or 106-mer MUC1 tandem repeat. Pre- and post-vaccinated plasma samples of these patients were compared in the ADCC assay and it could be clearly demonstrated that the induced MUC1 Abs can effect tumor cell killing. MUC1 Ab-dependent cell-mediated tumor cell killing may occur in vivo and the ADCC assay can be applied to monitor MUC1 vaccination trials. Copyright 2001 Wiley-Liss, Inc.

  7. Aberrantly glycosylated MUC1 is expressed on the surface of breast cancer cells and a target for antibody-dependent cell-mediated cytotoxicity

    DEFF Research Database (Denmark)

    Lavrsen, Kirstine; Madsen, Caroline B; Rasch, Morten G

    2013-01-01

    not covered by immunological tolerance in MUC1 humanized mice and man. The objective of this study was to determine if mouse antibodies to this Tn-MUC1 epitope induce antibody-dependent cellular cytotoxicity (ADCC) pivotal for their potential use in cancer immunotherapy. Binding affinity of mAb 5E5 directed...... to Tn-MUC1 was investigated using BiaCore. The availability of Tn-MUC1 on the surface of breast cancer cells was evaluated by immunohistochemistry, confocal microscopy, and flow cytometry, followed by in vitro assessment of antibody-dependent cellular cytotoxicity by mAb 5E5. Biacore analysis...... is expressed on the surface of breast cancer cells and a target for antibody-dependent cell-mediated cytotoxicity suggesting that antibodies targeting glycopeptide epitopes on mucins are strong candidates for cancer-specific immunotherapies....

  8. MEDI-563, a humanized anti-IL-5 receptor alpha mAb with enhanced antibody-dependent cell-mediated cytotoxicity function.

    Science.gov (United States)

    Kolbeck, Roland; Kozhich, Alexander; Koike, Masamichi; Peng, Li; Andersson, Cecilia K; Damschroder, Melissa M; Reed, Jennifer L; Woods, Robert; Dall'acqua, William W; Stephens, Geoffrey L; Erjefalt, Jonas S; Bjermer, Leif; Humbles, Alison A; Gossage, David; Wu, Herren; Kiener, Peter A; Spitalny, George L; Mackay, Charles R; Molfino, Nestor A; Coyle, Anthony J

    2010-06-01

    Peripheral blood eosinophilia and lung mucosal eosinophil infiltration are hallmarks of bronchial asthma. IL-5 is a critical cytokine for eosinophil maturation, survival, and mobilization. Attempts to target eosinophils for the treatment of asthma by means of IL-5 neutralization have only resulted in partial removal of airway eosinophils, and this warrants the development of more effective interventions to further explore the role of eosinophils in the clinical expression of asthma. We sought to develop a novel humanized anti-IL-5 receptor alpha (IL-5Ralpha) mAb with enhanced effector function (MEDI-563) that potently depletes circulating and tissue-resident eosinophils and basophils for the treatment of asthma. We used surface plasmon resonance to determine the binding affinity of MEDI-563 to FcgammaRIIIa. Primary human eosinophils and basophils were used to demonstrate antibody-dependent cell-mediated cytotoxicity. The binding epitope of MEDI-563 on IL-5Ralpha was determined by using site-directed mutagenesis. The consequences of MEDI-563 administration on peripheral blood and bone marrow eosinophil depletion was investigated in nonhuman primates. MEDI-563 binds to an epitope on IL-5Ralpha that is in close proximity to the IL-5 binding site, and it inhibits IL-5-mediated cell proliferation. MEDI-563 potently induces antibody-dependent cell-mediated cytotoxicity of both eosinophils (half-maximal effective concentration = 0.9 pmol/L) and basophils (half-maximal effective concentration = 0.5 pmol/L) in vitro. In nonhuman primates MEDI-563 depletes blood eosinophils and eosinophil precursors in the bone marrow. MEDI-563 might provide a novel approach for the treatment of asthma through active antibody-dependent cell-mediated depletion of eosinophils and basophils rather than through passive removal of IL-5. Copyright (c) 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  9. Enhancement of antibody-dependent cell-mediated cytotoxicity by endowing IgG with FcαRI (CD89) binding.

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    Borrok, M Jack; Luheshi, Nadia M; Beyaz, Nurten; Davies, Gareth C; Legg, James W; Wu, Herren; Dall'Acqua, William F; Tsui, Ping

    2015-01-01

    Fc effector functions such as antibody-dependent cell-mediated cytotoxicity (ADCC) and antibody-dependent cell-mediated phagocytosis (ADCP) are crucial to the efficacy of many antibody therapeutics. In addition to IgG, antibodies of the IgA isotype can also promote cell killing through engagement of myeloid lineage cells via interactions between the IgA-Fc and FcαRI (CD89). Herein, we describe a unique, tandem IgG1/IgA2 antibody format in the context of a trastuzumab variable domain that exhibits enhanced ADCC and ADCP capabilities. The IgG1/IgA2 tandem Fc format retains IgG1 FcγR binding as well as FcRn-mediated serum persistence, yet is augmented with myeloid cell-mediated effector functions via FcαRI/IgA Fc interactions. In this work, we demonstrate anti-human epidermal growth factor receptor-2 antibodies with the unique tandem IgG1/IgA2 Fc can better recruit and engage cytotoxic polymorphonuclear (PMN) cells than either the parental IgG1 or IgA2. Pharmacokinetics of IgG1/IgA2 in BALB/c mice are similar to the parental IgG, and far surpass the poor serum persistence of IgA2. The IgG1/IgA2 format is expressed at similar levels and with similar thermal stability to IgG1, and can be purified via standard protein A chromatography. The tandem IgG1/IgA2 format could potentially augment IgG-based immunotherapeutics with enhanced PMN-mediated cytotoxicity while avoiding many of the problems associated with developing IgAs.

  10. Natural killer (NK cell mediated antibody-dependent cellular cytotoxicity (ADCC in tumour immunotherapy with therapeutic antibodies

    Directory of Open Access Journals (Sweden)

    Ursula Jördis Eva Seidel

    2013-03-01

    Full Text Available In the last decade several therapeutic antibodies have been FDA and EMEA approved. Although their mechanisms of action in vivo is not fully elucidated, antibody-dependent cellular cytotoxicity (ADCC mediated by natural killer (NK cells is presumed to be a key effector function. A substantial role of ADCC has been demonstrated in vitro and in mouse tumour models. However, a direct in vivo effect of ADCC in tumour reactivity in humans remains to be shown. Several studies revealed a predictive value of FcγRIIIa-V158F polymorphism in monoclonal antibody treatment, indicating a potential effect of ADCC on outcome for certain indications. Furthermore, the use of therapeutic antibodies after allogeneic haematopoietic stem cell transplantation is an interesting option. Studying the role of the FcγRIIIa-V158F polymorphism and the influence of KIR-receptor-ligand incompatibility on ADCC in this approach may contribute to future transplantation strategies. Despite the success of approved second-generation antibodies in the treatment of several malignancies, efforts are made to further augment ADCC in vivo by antibody engineering. Here, we review currently used therapeutic antibodies for which ADCC has been suggested as effector function.

  11. Antibody dependent cellular phagocytosis (ADCP) and antibody dependent cellular cytotoxicity (ADCC) of breast cancer cells mediated by bispecific antibody, MDX-210.

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    Watanabe, M; Wallace, P K; Keler, T; Deo, Y M; Akewanlop, C; Hayes, D F

    1999-02-01

    MDX-210 is a bispecific antibody (BsAb) with specificity for both the proto-oncogene product of HER-2/neu (c-erbB-2) and FcgammaRI (CD64). HER-2/neu is overexpressed in malignant tissue of approximately 30% of patients with breast cancer, and FcgammaRI is expressed on human monocytes, macrophages, and IFN-gamma activated granulocytes. We investigated phagocytosis and cytolysis of cultured human breast cancer cells by human monocyte-derived macrophages (MDM) mediated by BsAb MDX-210, its partially humanized derivative (MDX-H210), and its parent MoAb 520C9 (anti-HER-2/neu) under various conditions. Purified monocytes were cultured with GM-CSF, M-CSF, or no cytokine for five or six days. Antibody dependent cellular phagocytosis (ADCP) and cytolysis (ADCC) assays were performed with the MDM and HER-2/neu positive target cells (SK-BR-3). ADCP was measured by two-color fluorescence flow cytometry using PKH2 (green fluorescent dye) and phycoerythrin-conjugated (red) monoclonal antibodies (MoAb) against human CD14 and CD11b. ADCC was measured with a non-radioactive LDH detection kit. Both BsAb MDX-210 (via FcgammaRI) and MoAb 520C9 (mouse IgG1, via FcgammaRII) mediated similar levels of ADCP and ADCC. ADCP mediated by BsAb MDX-H210 was identical to that mediated by BsAb MDX-210. Confocal microscopy demonstrated that dual-labeled cells represented true phagocytosis. Both ADCP and ADCC were higher when MDM were pre-incubated with GM-CSF than when incubated with M-CSF. BsAb MDX-210 is as active in vitro as the parent MoAb 520C9 in inducing both phagocytosis and cytolysis of MDM. MDX-210 and its partially humanized derivative, MDX-H210, mediated similar levels of ADCP. GM-CSF appears to superior to M-CSF in inducing MDM-mediated ADCC and ADCP. These studies support the ongoing clinical investigations of BsAb MDX-210 and its partially humanized derivative.

  12. Trastuzumab mediates antibody-dependent cell-mediated cytotoxicity and phagocytosis to the same extent in both adjuvant and metastatic HER2/neu breast cancer patients.

    Science.gov (United States)

    Petricevic, Branka; Laengle, Johannes; Singer, Josef; Sachet, Monika; Fazekas, Judit; Steger, Guenther; Bartsch, Rupert; Jensen-Jarolim, Erika; Bergmann, Michael

    2013-12-12

    Monoclonal antibodies (mAb), such as trastuzumab are a valuable addition to breast cancer therapy. Data obtained from neoadjuvant settings revealed that antibody-dependent cell-mediated cytotoxicity (ADCC) is a major mechanism of action for the mAb trastuzumab. Conflicting results still call into question whether disease progression, prolonged treatment or concomitant chemotherapy influences ADCC and related immunological phenomena. We analyzed the activity of ADCC and antibody-dependent cell-mediated phagocytosis (ADCP) of peripheral blood mononuclear cells (PBMCs) from human epidermal growth factor receptor 2 (HER2/neu) positive breast cancer patients receiving trastuzumab therapy either in an adjuvant (n = 13) or metastatic (n = 15) setting as well as from trastuzumab treatment-naive (t-naive) HER2/neu negative patients (n = 15). PBMCs from healthy volunteers (n = 24) were used as controls. ADCC and ADCP activity was correlated with the expression of antibody binding Fc-gamma receptor (FcγR)I (CD64), FcγRII (CD32) and FcγRIII (CD16) on CD14+ (monocytes) and CD56+ (NK) cells, as well as the expression of CD107a+ (LAMP-1) on CD56+ cells and the total amount of CD4+CD25+FOXP3+ (Treg) cells. In metastatic patients, markers were correlated with progression-free survival (PFS). ADCC activity was significantly down regulated in metastatic, adjuvant and t-naive patient cohorts as compared to healthy controls. Reduced ADCC activity was inversely correlated with the expression of CD107a on CD56+ cells in adjuvant patients. ADCC and ADCP activity of the patient cohorts were similar, regardless of treatment duration or additional chemotherapy. PFS in metastatic patients inversely correlated with the number of peripheral Treg cells. The reduction of ADCC in patients as compared to healthy controls calls for adjuvant strategies, such as immune-enhancing agents, to improve the activity of trastuzumab. However, efficacy of trastuzumab-specific ADCC and ADCP appears not to

  13. The impact of HLA class I-specific killer cell immunoglobulin-like receptors on antibody-dependent natural killer cell-mediated cytotoxicity and organ allograft rejection

    Directory of Open Access Journals (Sweden)

    Raja Rajalingam

    2016-12-01

    Full Text Available Natural killer (NK cells of the innate immune system are cytotoxic lymphocytes that play important roles following transplantation of solid organs and hematopoietic stem cells. Recognition of self HLA class I molecules by inhibitory killer cell immunoglobulin-like receptors (KIR is involved in the calibration of NK cell effector capacities during a developmental stage, allowing the subsequent recognition and elimination of target cells with decreased expression of self HLA class I (due to virus infection or tumor transformation or HLA class I disparities (in the setting of allogeneic transplantation. NK cells expressing an inhibitory KIR binding self HLA can be activated when confronted with allografts lacking a ligand for the inhibitory receptor. Following the response of the adaptive immune system, NK cells can further destroy allograft endothelium by antibody-dependent cell-mediated cytotoxicity (ADCC, triggered through cross-linking of the CD16 Fc receptor by donor-specific antibodies bound to allograft. Upon recognizing allogeneic target cells, NK cells also secrete cytokines and chemokines that drive maturation of dendritic cells to promote cellular and humoral adaptive immune responses against the allograft. The cumulative activating and inhibitory signals generated by ligation of the receptors regulates mature NK cell killing of target cells and their production of cytokines and chemokines. This review summarizes the role of NK cells in allograft rejection and proposes mechanistic concepts that indicate a prominent role for KIR-HLA interactions in facilitating NK cells for Fc receptor-mediated ADCC effector function involved in antibody-mediated rejection of solid organ transplants.

  14. Tyrosine kinase inhibitors as modulators of trastuzumab-mediated antibody-dependent cell-mediated cytotoxicity in breast cancer cell lines.

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    Collins, Denis M; Gately, Kathy; Hughes, Clare; Edwards, Connla; Davies, Anthony; Madden, Stephen F; O'Byrne, Kenneth J; O'Donovan, Norma; Crown, John

    2017-09-01

    Trastuzumab is an anti-HER2 monoclonal antibody (mAb) therapy capable of antibody-dependent cell-mediated cytotoxicity (ADCC) and used in the treatment of HER2+ breast cancer. Through interactions with FcƴR+ immune cell subsets, trastuzumab functions as a passive immunotherapy. The EGFR/HER2-targeting tyrosine kinase inhibitor (TKI) lapatinib and the next generation TKIs afatinib and neratinib, can alter HER2 levels, potentially modulating the ADCC response to trastuzumab. Using LDH-release assays, we investigated the impact of antigen modulation, assay duration and peripheral blood mononuclear cell (PBMC) activity on trastuzumab-mediated ADCC in breast cancer models of maximal (SKBR3) and minimal (MCF-7) target antigen expression to determine if modulating the ADCC response to trastuzumab using TKIs may be a viable approach for enhancing tumor immune reactivity. HER2 levels were determined in lapatinib, afatinib and neratinib-treated SKBR3 and MCF-7 using high content analysis (HCA). Trastuzumab-mediated ADCC was assessed following treatment with TKIs utilising a colorimetric LDH release-based protocol at 4 and 12h timepoints. PBMC activity was assessed against non-MHC-restricted K562 cells. A flow cytometry-based method (CFSE/7-AAD) was also used to measure trastuzumab-mediated ADCC in medium-treated SKBR3 and MCF-7. HER2 antigen levels were significantly altered by the three TKIs in both cell line models. The TKIs significantly reduced LDH levels directly in SKBR3 cells but not MCF-7. Lapatinib and neratinib augment trastuzumab-related ADCC in SKBR3 but the effect was not consistent with antigen expression levels and was dependent on volunteer PBMC activity (vs. K562). A 12h assay timepoint produced more consistent results. Trastuzumab-mediated ADCC (PBMC:target cell ratio of 10:1) was measured at 7.6±4.7% (T12) by LDH assay and 19±3.2 % (T12) using the flow cytometry-based method in the antigen-low model MCF-7. In the presence of effector cells with high

  15. Differential effects of IL-2 and IL-21 on expansion of the CD4+ CD25+ Foxp3+ T regulatory cells with redundant roles in natural killer cell mediated antibody dependent cellular cytotoxicity in chronic lymphocytic leukemia.

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    Gowda, Aruna; Ramanunni, Asha; Cheney, Carolyn; Rozewski, Darlene; Kindsvogel, Wayne; Lehman, Amy; Jarjoura, David; Caligiuri, Michael; Byrd, John C; Muthusamy, Natarajan

    2010-01-01

    CD4(+) CD25(+) regulatory T cells are expanded in solid and hematological malignancies including chronic lymphocytic leukemia (CLL). Several cytokines and co-stimulatory molecules are required for generation, survival and maintenance of their suppressive effect. We and others have shown direct cytotoxic effect of the novel common gamma chain cytokine interleukin (IL)-21 on primary B cells from CLL patients. Since members of this family of cytokines are known to exhibit their effects on diverse immune cells, we have examined the effects of IL-21 on CLL patient derived regulatory T cell (Treg) induction, expansion and the inhibitory effect on natural killer cells in vitro. We demonstrate here the expression of IL-21 receptor in CD4(+)CD25(High) regulatory cells from CLL patients. In contrast to IL-2, the IL-21 cytokine failed to mediate expansion of regulatory T cells or induced expression of Foxp3 in CD4(+)CD25(Intermediate) or CD4(+)CD25(Dim/-) T cells in whole blood derived from CLL patients. Interestingly, in contrast to their differential effects on expansion of the CD4(+)CD25(+)Foxp3(+)T cells, IL-2 and IL-21 exhibited a redundant role in Treg mediated suppression of NK cell mediated antibody dependent cytotoxicity function. Given the infusion related toxicities and pro-survival effect of IL-2 in CLL, these studies provide a rationale to explore IL-21 as an alternate gamma chain cytokine in CLL therapy.

  16. Athymic nude rat. III natural cell mediated cytotoxicity.

    NARCIS (Netherlands)

    W.H. de Jong; P.A. Steerenberg; P.S. Ursem; A.D.M.E. Osterhaus (Albert); J.G. Vos (Joseph); E.J. Ruitenberg (Joost)

    1980-01-01

    textabstractHomozygous rnu/rnu and heterozygous +/rnu rats were investigated and compared with each other for the existence of natural cell-mediated cytotoxicity. Investigated were total, adherent, and nonadherent cell populations from spleen, peritoneal cavity, and mesenteric lymph node. The

  17. Antibody targeting of Cathepsin S induces antibody-dependent cellular cytotoxicity

    Directory of Open Access Journals (Sweden)

    Kwok Hang Fai

    2011-12-01

    Full Text Available Abstract Background Proteolytic enzymes have been implicated in driving tumor progression by means of their cancer cell microenvironment activity where they promote proliferation, differentiation, apoptosis, migration, and invasion. Therapeutic strategies have focused on attenuating their activity using small molecule inhibitors, but the association of proteases with the cell surface during cancer progression opens up the possibility of targeting these using antibody dependent cellular cytotoxicity (ADCC. Cathepsin S is a lysosomal cysteine protease that promotes the growth and invasion of tumour and endothelial cells during cancer progression. Our analysis of colorectal cancer patient biopsies shows that cathepsin S associates with the cell membrane indicating a potential for ADCC targeting. Results Here we report the cell surface characterization of cathepsin S and the development of a humanized antibody (Fsn0503h with immune effector function and a stable in vivo half-life of 274 hours. Cathepsin S is expressed on the surface of tumor cells representative of colorectal and pancreatic cancer (23%-79% positive expression. Furthermore the binding of Fsn0503h to surface associated cathepsin S results in natural killer (NK cell targeted tumor killing. In a colorectal cancer model Fsn0503h elicits a 22% cytotoxic effect. Conclusions This data highlights the potential to target cell surface associated enzymes, such as cathepsin S, as therapeutic targets using antibodies capable of elicitingADCC in tumor cells.

  18. Malignant monoblasts can function as effector cells in natural killer cell and antibody-dependent cellular cytotoxicity assays

    DEFF Research Database (Denmark)

    Hokland, P; Hokland, M; Ellegaard, J

    1981-01-01

    This is the first report describing natural killer (NK) and antibody-dependent cellular cytotoxicity (ADCC) of malignant monoblasts. Pure acute monoblastic leukemia was diagnosed in bone marrow aspirations from two patients by use of conventional cytochemical methods as well as multiple immunologic...

  19. Antibody-dependent cellular cytotoxicity in antimyelin antibody-induced oligodendrocyte damage in vitro.

    Science.gov (United States)

    Griot-Wenk, M; Griot, C; Pfister, H; Vandevelde, M

    1991-08-01

    Treatment of dissociated murine brain cell cultures with an antibody recognizing galactocerebroside (GalC) led to degeneration of oligodendrocytes with loss of their cell processes. F(ab')2 fragments prepared from this antibody showed no effect. The anti-GalC antibody--but not its F(ab')2 fragments b2 was able to stimulate macrophages in these cultures as seen in a chemiluminescence assay. Therefore, antibodies bound to oligodendrocytes stimulated nearby macrophages by interacting with their Fc receptors. The oligodendroglial damage coincided with the release of toxic compounds by the stimulated macrophages, since treatment of the cultures with the anti-GalC antibody and a variety of other macrophage stimulating agents led to secretion of reactive oxygen species and--in some experiments--tumor necrosis factor, both known to be toxic for oligodendrocytes. These in vitro experiments show evidence that antibody-dependent cellular cytotoxicity may be an important mechanism of tissue destruction in inflammatory demyelinating diseases.

  20. Clinical Cancer Therapy by NK Cells via Antibody-Dependent Cell-Mediated Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Kory L. Alderson

    2011-01-01

    Full Text Available Natural killer (NK cells are powerful effector cells that can be directed to eliminate tumor cells through tumor-targeted monoclonal antibodies (mAbs. Some tumor-targeted mAbs have been successfully applied in the clinic and are included in the standard of care for certain malignancies. Strategies to augment the antitumor response by NK cells have led to an increased understanding of how to improve their effector responses. Next-generation reagents, such as molecularly modified mAbs and mAb-cytokine fusion proteins (immunocytokines, ICs designed to augment NK-mediated killing, are showing promise in preclinical and some clinical settings. Continued research into the antitumor effects induced by NK cells and tumor-targeted mAbs suggests that additional intrinsic and extrinsic factors may influence the antitumor response. Therefore more research is needed that focuses on evaluating which NK cell and tumor criteria are best predictive of a clinical response and which combination immunotherapy regimens to pursue for distinct clinical settings.

  1. Natural killer cell cytotoxicity and antibody-dependent cellular cytotoxicity to herpes simplex virus-infected cells in human pregnancy.

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    Gonik, B; Loo, L S; West, S; Kohl, S

    1987-01-01

    Natural killer cell (NKC) cytotoxicity and antibody-dependent cellular cytotoxicity (ADCC) represent the ability of human leukocyte effector cells to destroy target cells in the absence and presence of antibody, respectively. Since these immune systems play a pivotal role in the body's primary lines of defense against a variety of pathogens including herpes simplex virus (HSV), a study was undertaken to evaluate the influence of pregnancy on these systems. Eleven uncomplicated gravidas were followed serially through each trimester and compared to 11 nonpregnant female controls. Mononuclear cells were acquired by Ficoll-Hypaque centrifugation of heparinized blood. Chang liver cells infected with HSV-I were utilized as target cells in a 51Cr release assay. Mean NKC values in the pregnant patients were uniformly lower than in the controls. No similar decreases in ADCC activity were observed in a comparison between the two study populations. These data support previous observations suggesting that pregnancy represents a relatively immunocompromised state. Differences apparently exist between NKC and ADCC effector cell populations with regard to the influence of pregnancy. Although these physiologic alterations in immunoregulation may help support the fetoplacental allograph, detrimental conditions may exist regarding susceptibility to various pathogens such as HSV.

  2. 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.

  3. HIV-1 Env- and Vpu-Specific Antibody-Dependent Cellular Cytotoxicity Responses Associated with Elite Control of HIV.

    Science.gov (United States)

    Madhavi, Vijaya; Wines, Bruce D; Amin, Janaki; Emery, Sean; Lopez, Ester; Kelleher, Anthony; Center, Rob J; Hogarth, P Mark; Chung, Amy W; Kent, Stephen J; Stratov, Ivan

    2017-09-15

    Studying HIV-infected individuals who control HIV replication (elite controllers [ECs]) enables exploration of effective anti-HIV immunity. HIV Env-specific and non-Env-specific antibody-dependent cellular cytotoxicity (ADCC) may contribute to protection from progressive HIV infection, but the evidence is limited. We recruited 22 ECs and matched them with 44 viremic subjects. HIV Env- and Vpu-specific ADCC responses in sera were studied using a novel enzyme-linked immunosorbent assay (ELISA)-based dimeric recombinant soluble FcγRIIIa (rsFcγRIIIa)-binding assay, surface plasmon resonance, antibody-dependent natural killer (NK) cell activation assays, and ADCC-mediated killing assays. ECs had higher levels of HIV Env-specific antibodies capable of binding FcγRIIIa, activating NK cells, and mediating granzyme B activity (all P Env-specific and Vpu epitope-specific ADCC in effective immune responses against HIV among ECs. Our findings have implications for understanding the role of ADCC in HIV control. IMPORTANCE Understanding immune responses associated with elite control of HIV may aid the development of immunotherapeutic and vaccine strategies for controlling HIV infection. Env is a major HIV protein target of functional antibody responses that are heightened in ECs. Interestingly, EC antibodies also target Vpu, an accessory protein crucial to HIV, which degrades CD4 and antagonizes tetherin. Antibodies specific to Vpu are a common feature of the immune response of ECs that may prove to be of functional importance to the design of improved ADCC-based immunotherapy and preventative HIV vaccines. Copyright © 2017 American Society for Microbiology.

  4. HIV-Specific Antibody-Dependent Cellular Cytotoxicity (ADCC) -Mediating Antibodies Decline while NK Cell Function Increases during Antiretroviral Therapy (ART)

    DEFF Research Database (Denmark)

    Skov Jensen, Sanne; Fomsgaard, Anders; Borggren, Marie

    2015-01-01

    Understanding alterations in HIV-specific immune responses during antiretroviral therapy (ART), such as antibody-dependent cellular cytotoxicity (ADCC), is important in the development of novel strategies to control HIV-1 infection. This study included 53 HIV-1 positive individuals. We evaluated...... during ART. These findings suggest improved cytotoxic function of the NK cells if initiating ART early during infection, while the levels of ADCC mediating antibodies declined during ART....

  5. Natural killer cell-mediated cytotoxicity is increased by a type II arabinogalactan from Anoectochilus formosanus.

    Science.gov (United States)

    Yang, Li-Chan; Lai, Ching-Yi; Lin, Wen-Chuan

    2017-01-02

    This study investigated the effects of a type II arabinogalactan from Anoectochilus formosanus (AGAF) on natural killer (NK) cell-mediated cytotoxicity and the possible underlying mechanisms. This study reported that sustained exposure to AGAF increased NK-92MI cell-mediated cytotoxicity in a time- and concentration-dependent manner, as characterized according to the cellular lactic dehydrogenase leakage from K562 leukemia cells. Additionally, antibody neutralization studies have reported that interferon (IFN)-γ, but not perforin or tumor necrosis factor-α, released by NK-92MI NK cells is crucial in enhancing cytotoxicity through an autocrine loop. In this study, AGAF was further demonstrated to induce IFN-γ expression, increasing the susceptibility to NK-92MI cell-mediated cytotoxicity through the toll-like receptor (TLR)-2, TLR4, extracellular signal-regulated kinase, p38 mitogen-activated protein kinase, and nuclear factor-κB pathways. A pharmacological study revealed that Janus kinase 2/signal transducers and activators of the signal transducers and of transcription 3 signaling are involved in IFN-γ-induced NK cell-mediated cytotoxicity. Copyright © 2016. Published by Elsevier Ltd.

  6. Inhibition of natural killer cell-mediated cytotoxicity by lipids extracted from Mycobacterium bovis BCG

    NARCIS (Netherlands)

    Roozemond, R. C.; Halperin, M.; Das, P. K.

    1985-01-01

    Several studies have demonstrated an augmentation of natural killer (NK) cell-mediated cytotoxicity by various adjuvants including BCG. Inhibitory effects of BCG have also been reported, particularly for relatively high doses. Because the cell wall of Mycobacterium bovis BCG contains a high

  7. Augmentation of antibody-dependent cellular cytotoxicity with defucosylated monoclonal antibodies in patients with GI-tract cancer.

    Science.gov (United States)

    Nakajima, Takahiro; Okayama, Hirokazu; Ashizawa, Mai; Noda, Masaru; Aoto, Keita; Saito, Motonobu; Monma, Tomoyuki; Ohki, Shinji; Shibata, Masahiko; Takenoshita, Seiichi; Kono, Koji

    2018-02-01

    Enhancement of antibody-dependent cellular cytotoxicity (ADCC) with some modalities may be a promising approach to enhance the efficacy of therapeutic monoclonal antibodies (mAbs). It has previously been demonstrated that the removal of fucose from antibody oligosaccharides (defucosylation) leads to augmentation of ADCC activity. To establish clinically relevant evidence of this procedure, the present study evaluated trastuzumab- and cetuximab-mediated ADCC by comparing defucosylated mAbs with conventional mAbs using peripheral blood mononuclear cells (PBMCs). PBMCs were isolated from 20 patients with gastrointestinal tract cancer and 10 healthy volunteers. ADCCs were measured using PBMCs as effector cells and two gastric cancer cell lines as target cells. ADCCs were significantly enhanced with defucosylated mAbs compared with conventional mAbs using PBMC from the healthy donors and patients with cancer. The results confirmed that the cetuximab- and trastuzumab-mediated ADCCs in advanced disease were impaired in comparison to those in early disease or healthy individuals. However, when the defucosylated mAbs were used instead of the conventional mAbs, the ADCC activities in the advanced cases were almost comparable with those in early disease or healthy individuals. Furthermore, the expression of ADCC associated molecules were modified toward immunosuppressive status with a mitogen-activated protein kinase inhibitor in vitro , the conventional cetuximab- and trastuzumab-mediated ADCC was downregulated, and the defucosylated mAbs overcome the downregulation of ADCC. In conclusion, defucosylated therapeutic mAbs may enhance ADCC activities in patients with cancer, which may lead to more effective anti-cancer treatments.

  8. Breadth of HIV-1 Env-specific antibody-dependent cellular cytotoxicity: relevance to global HIV vaccine design.

    Science.gov (United States)

    Madhavi, Vijaya; Wren, Leia H; Center, Rob J; Gonelli, Christopher; Winnall, Wendy R; Parsons, Matthew S; Kramski, Marit; Kent, Stephen J; Stratov, Ivan

    2014-08-24

    The objective of this study is to determine the breadth of HIV-1 Env-specific antibody-dependent cellular cytotoxicity (ADCC) in HIV controllers and HIV progressors with a view to design globally relevant HIV vaccines. The breadth of ADCC towards four major HIV-1 Env subtypes was measured in vitro for 11 HIV controllers and 11 HIV progressors. Plasma from 11 HIV controllers (including long-term slow progressors, viremic controllers, elite controller and posttreatment controller) and 11 HIV progressors, mostly infected with HIV-1 subtype B, was analysed for ADCC responses. ADCC assays were performed against 10 HIV-1 gp120 and 8 gp140 proteins from four major HIV-1 subtypes (A, B, C and E) and 3 glycosylation-mutant gp140 proteins. ADCC-mediated natural killer cell activation was significantly broader (P = 0.02) and of higher magnitude (P HIV controllers than in HIV progressors. HIV controllers also showed significantly higher magnitude of ADCC-mediated killing of Env-coated target cells than HIV progressors to both HIV-1 subtype B and the heterologous subtype E gp140 (P = 0.001). We found good ADCC reactivity to subtype B and E Envs, less cross-reactivity to subtype A and minimal cross-reactivity to subtype C Envs. Glycosylation-dependent ADCC epitopes comprise a significant proportion of the total Env-specific ADCC response, as evident from the reduction in ADCC to nonglycosylated form of HIV-1 gp140 (P = 0.004). HIV controllers have robust ADCC responses that recognize a broad range of HIV-1 Env. Glycosylation of Env was found to be important for recognition of ADCC epitopes. Identifying conserved ADCC epitopes will assist in designing globally relevant ADCC-based HIV vaccines.

  9. Cytotoxic T cells mediate pathology and metastasis in cutaneous leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Fernanda O Novais

    Full Text Available Disease progression in response to infection can be strongly influenced by both pathogen burden and infection-induced immunopathology. While current therapeutics focus on augmenting protective immune responses, identifying therapeutics that reduce infection-induced immunopathology are clearly warranted. Despite the apparent protective role for murine CD8⁺ T cells following infection with the intracellular parasite Leishmania, CD8⁺ T cells have been paradoxically linked to immunopathological responses in human cutaneous leishmaniasis. Transcriptome analysis of lesions from Leishmania braziliensis patients revealed that genes associated with the cytolytic pathway are highly expressed and CD8⁺ T cells from lesions exhibited a cytolytic phenotype. To determine if CD8⁺ T cells play a causal role in disease, we turned to a murine model. These studies revealed that disease progression and metastasis in L. braziliensis infected mice was independent of parasite burden and was instead directly associated with the presence of CD8⁺ T cells. In mice with severe pathology, we visualized CD8⁺ T cell degranulation and lysis of L. braziliensis infected cells. Finally, in contrast to wild-type CD8⁺ T cells, perforin-deficient cells failed to induce disease. Thus, we show for the first time that cytolytic CD8⁺ T cells mediate immunopathology and drive the development of metastatic lesions in cutaneous leishmaniasis.

  10. Antiglycopeptide Mouse Monoclonal Antibody LpMab-21 Exerts Antitumor Activity Against Human Podoplanin Through Antibody-Dependent Cellular Cytotoxicity and Complement-Dependent Cytotoxicity.

    Science.gov (United States)

    Kato, Yukinari; Kunita, Akiko; Fukayama, Masashi; Abe, Shinji; Nishioka, Yasuhiko; Uchida, Hiroaki; Tahara, Hideaki; Yamada, Shinji; Yanaka, Miyuki; Nakamura, Takuro; Saidoh, Noriko; Yoshida, Kanae; Fujii, Yuki; Honma, Ryusuke; Takagi, Michiaki; Ogasawara, Satoshi; Murata, Takeshi; Kaneko, Mika K

    2017-02-01

    The interaction between podoplanin (PDPN) and C-type lectin-like receptor 2 (CLEC-2) is involved in tumor malignancy. We have established many monoclonal antibodies (mAbs) against human podoplanin using the cancer-specific mAb (CasMab) technology. LpMab-21, one of the mouse antipodoplanin mAbs, is of the IgG 2a subclass, and its minimum epitope was determined to be Thr76-Arg79 of the human podoplanin. Importantly, sialic acid is linked to Thr76; therefore, LpMab-21 is an antiglycopeptide mAb (GpMab). In this study, we investigated whether LpMab-21 shows antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against human podoplanin-expressing cancer cell lines in vitro and also studied its antitumor activities using a xenograft model. LpMab-21 showed high ADCC and CDC activities against not only podoplanin-expressing Chinese hamster ovary cells but also LN319 glioblastoma cells and PC-10 lung cancer cells, both of which endogenously express podoplanin. Furthermore, LpMab-21 decreased tumor growth in vivo, indicating that LpMab-21 could be useful for antibody therapy against human podoplanin-expressing cancers.

  11. Immunization with Clinical HIV-1 Env Proteins Induces Broad Antibody Dependent Cellular Cytotoxicity-Mediating Antibodies in a Rabbit Vaccination Model

    DEFF Research Database (Denmark)

    Karlsson, Ingrid; Borggren, Marie; Jensen, Sanne Skov

    2018-01-01

    The induction of both neutralizing antibodies and non-neutralizing antibodies with effector functions, for example, antibody-dependent cellular cytotoxicity (ADCC), is desired in the search for effective vaccines against HIV-1. In the pursuit of novel immunogens capable of inducing an efficient...... of inducing antibodies with ADCC activity did not necessarily induce neutralizing activity and vice versa. Nevertheless, we identified vaccine candidates that were able to concurrently induce both types of responses and that had ADCC activity that was cross-reactive between different subtypes. When searching...

  12. A novel antibody-dependent cellular cytotoxicity mechanism involved in defense against malaria requires costimulation of monocytes FcgammaRII and FcgammaRIII

    DEFF Research Database (Denmark)

    Jafarshad, Ali; Dziegiel, Morten Hanefeld; Lundquist, Rasmus

    2007-01-01

    Clinical experiments have shown that the Ab-dependent cell-mediated inhibition of Plasmodium falciparum is a major mechanism controlling malaria parasitemia and thereby symptoms. In this study, we demonstrate that a single merozoite per monocyte (MN) is sufficient to trigger optimal antiparasitic......-dependent cellular cytotoxicity and implies that all MN are not equally effective. These findings have both fundamental and practical implications, particularly for vaccine discovery....

  13. Sensitive Detection of the Natural Killer Cell-Mediated Cytotoxicity of Anti-CD20 Antibodies and Its Impairment by B-Cell Receptor Pathway Inhibitors

    Directory of Open Access Journals (Sweden)

    Floyd Hassenrück

    2018-01-01

    Full Text Available The antibody-dependent cell-mediated cytotoxicity (ADCC of the anti-CD20 monoclonal antibodies (mAbs rituximab and obinutuzumab against the cell line Raji and isolated CLL cells and its potential impairment by kinase inhibitors (KI was determined via lactate dehydrogenase release or calcein retention, respectively, using genetically modified NK92 cells expressing CD16-176V as effector cells. Compared to peripheral blood mononuclear cells, recombinant effector cell lines showed substantial alloreactivity-related cytotoxicity without addition of mAbs but afforded determination of ADCC with reduced interassay variability. The cytotoxicity owing to alloreactivity was less susceptible to interference by KI than the ADCC of anti-CD20 mAbs, which was markedly diminished by ibrutinib, but not by idelalisib. Compared to rituximab, the ADCC of obinutuzumab against primary CLL cells showed approximately 30% higher efficacy and less interference with KI. Irreversible BTK inhibitors at a clinically relevant concentration of 1 μM only weakly impaired the ADCC of anti-CD20 mAbs, with less influence in combinations with obinutuzumab than with rituximab and by acalabrutinib than by ibrutinib or tirabrutinib. In summary, NK cell line-based assays permitted the sensitive detection of ADCC of therapeutic anti-CD20 mAbs against CLL cells and of the interference of KI with this important killing mechanism.

  14. Neutralizing Antibody Response and Antibody-Dependent Cellular Cytotoxicity in HIV-1-Infected Individuals from Guinea-Bissau and Denmark

    DEFF Research Database (Denmark)

    Borggren, Marie; Jensen, Sanne Skov; Heyndrickx, Leo

    2016-01-01

    cytotoxicity (ADCC) against local and nonlocal circulating HIV-1 strains. The neutralizing activity did not demonstrate higher potential against local circulating strains according to geography and subtype determination, but the plasma from Danish individuals demonstrated significantly higher inhibitory...

  15. Effect of radiation on cell-mediated cytotoxicity and lymphocyte subpopulations in patients with ovarian carcinoma

    International Nuclear Information System (INIS)

    Kohorn, E.I.; Mitchell, M.S.; Dwyer, J.M.; Knowlton, A.H.; Klein-Angerer, S.

    1978-01-01

    Lymphocyte subpopulations and cell-mediated cytotoxicity (CMI) were studied during radiation therapy in 16 patients with ovarian carcinoma. The total lymphocyte count became depressed in all patients. The depression was more marked among T cells, while the proportion of B cells remained unaffected. In patients with Stage I and II ovarian cancer, CMI was depressed significantly by radiotherapy after 7 days of treatment, remained low at 14 days but recovered despite continuation of radiation. This depression of CMI occurred at a delivered dose of 1,000 rads with subsequent recovery. Patients with Stage III ovarian cancer given pelvic and abdominal radiation were found to have no consistent depression of CMI, a finding similar to that in Stage III ovarian carcinoma patients given chemotherapy

  16. Immunological low-dose radiation modulates the pediatric medulloblastoma antigens and enhances antibody-dependent cellular cytotoxicity.

    Science.gov (United States)

    Das, Arabinda; McDonald, Daniel; Lowe, Stephen; Bredlau, Amy-Lee; Vanek, Kenneth; Patel, Sunil J; Cheshier, Samuel; Eskandari, Ramin

    2017-03-01

    Immunotherapy can be an effective treatment for pediatric medulloblastoma (MB) patients. However, major subpopulations do not respond to immunotherapy, due to the lack of antigenic mutations or the immune-evasive properties of MB cells. Clinical observations suggest that radiation therapy (RT) may expand the therapeutic reach of immunotherapy. The aim of the present investigation is to study the effect of low-dose X-ray radiation (LDXR, 1 Gy) on the functional immunological responses of MB cells (DAOY, D283, and D341). Induction of MB cell death was examined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Production of reactive oxygen species (ROS) was measured by fluorescent probes. Changes in the expression of  human leukocyte antigen (HLA) molecules and caspase-3 activities during treatment were analyzed using Western blotting and caspase-3 assay. Western blot analysis demonstrated that LDXR upregulated the expression of HLA class I and HLA II molecules by more than 20% compared with control and high-dose (12 Gy) groups in vitro. Several of these HLA subtypes, such as MAGE C1, CD137, and ICAM-1, have demonstrated upregulation. In addition, LDXR increases ROS production in association with phosphorylation of NF-κB and cell surface expression of mAb target molecules (HER2 and VEGF). These data suggest that a combined LDXR and mAb therapy can create a synergistic effect in vitro. These results suggest that LDXR modulates HLA molecules, leading to alterations in T-cell/tumor-cell interaction and enhancement of T-cell-mediated MB cell death. Also, low-dose radiotherapy combined with monoclonal antibody therapy may one day augment the standard treatment for MB, but more investigation is needed to prove its utility as a new therapeutic combination for MB patients.

  17. HIV-Specific Antibody-Dependent Cellular Cytotoxicity (ADCC) -Mediating Antibodies Decline while NK Cell Function Increases during Antiretroviral Therapy (ART).

    Science.gov (United States)

    Jensen, Sanne Skov; Fomsgaard, Anders; Borggren, Marie; Tingstedt, Jeanette Linnea; Gerstoft, Jan; Kronborg, Gitte; Rasmussen, Line Dahlerup; Pedersen, Court; Karlsson, Ingrid

    2015-01-01

    Understanding alterations in HIV-specific immune responses during antiretroviral therapy (ART), such as antibody-dependent cellular cytotoxicity (ADCC), is important in the development of novel strategies to control HIV-1 infection. This study included 53 HIV-1 positive individuals. We evaluated the ability of effector cells and antibodies to mediate ADCC separately and in combination using the ADCC-PanToxiLux assay. The ability of the peripheral blood mononuclear cells (PBMCs) to mediate ADCC was significantly higher in individuals who had been treated with ART before seroconversion, compared to the individuals initiating ART at a low CD4+ T cell count (ART-naïve individuals. The frequency of CD16 expressing natural killer (NK) cells correlated with both the duration of ART and Granzyme B (GzB) activity. In contrast, the plasma titer of antibodies mediating ADCC declined during ART. These findings suggest improved cytotoxic function of the NK cells if initiating ART early during infection, while the levels of ADCC mediating antibodies declined during ART.

  18. Humanised IgG1 antibody variants targeting membrane-bound carcinoembryonic antigen by antibody-dependent cellular cytotoxicity and phagocytosis.

    Science.gov (United States)

    Ashraf, S Q; Umana, P; Mössner, E; Ntouroupi, T; Brünker, P; Schmidt, C; Wilding, J L; Mortensen, N J; Bodmer, W F

    2009-11-17

    The effect of glycoengineering a membrane specific anti-carcinoembryonic antigen (CEA) (this paper uses the original term CEA for the formally designated CEACAM5) antibody (PR1A3) on its ability to enhance killing of colorectal cancer (CRC) cell lines by human immune effector cells was assessed. In vivo efficacy of the antibody was also tested. The antibody was modified using EBNA cells cotransfected with beta-1,4-N-acetylglucosaminyltransferase III and the humanised hPR1A3 antibody genes. The resulting alteration of the Fc segment glycosylation pattern enhances the antibody's binding affinity to the FcgammaRIIIa receptor on human immune effector cells but does not alter the antibody's binding capacity. Antibody-dependent cellular cytotoxicity (ADCC) is inhibited in the presence of anti-FcgammaRIII blocking antibodies. This glycovariant of hPR1A3 enhances ADCC 10-fold relative to the parent unmodified antibody using either unfractionated peripheral blood mononuclear or natural killer (NK) cells and CEA-positive CRC cells as targets. NK cells are far more potent in eliciting ADCC than either freshly isolated monocytes or granulocytes. Flow cytometry and automated fluorescent microscopy have been used to show that both versions of hPR1A3 can induce antibody-dependent cellular phagocytosis (ADCP) by monocyte-derived macrophages. However, the glycovariant antibody did not mediate enhanced ADCP. This may be explained by the relatively low expression of FcgammaRIIIa on cultured macrophages. In vivo studies show the efficacy of glycoengineered humanised IgG1 PR1A3 in significantly improving survival in a CRC metastatic murine model. The greatly enhanced in vitro ADCC activity of the glycoengineered version of hPR1A3 is likely to be clinically beneficial.

  19. Narcolepsy-Associated HLA Class I Alleles Implicate Cell-Mediated Cytotoxicity

    Science.gov (United States)

    Tafti, Mehdi; Lammers, Gert J.; Dauvilliers, Yves; Overeem, Sebastiaan; Mayer, Geert; Nowak, Jacek; Pfister, Corinne; Dubois, Valérie; Eliaou, Jean-François; Eberhard, Hans-Peter; Liblau, Roland; Wierzbicka, Aleksandra; Geisler, Peter; Bassetti, Claudio L.; Mathis, Johannes; Lecendreux, Michel; Khatami, Ramin; Heinzer, Raphaël; Haba-Rubio, José; Feketeova, Eva; Baumann, Christian R.; Kutalik, Zoltán; Tiercy, Jean-Marie

    2016-01-01

    Study Objectives: Narcolepsy with cataplexy is tightly associated with the HLA class II allele DQB1*06:02. Evidence indicates a complex contribution of HLA class II genes to narcolepsy susceptibility with a recent independent association with HLA-DPB1. The cause of narcolepsy is supposed be an autoimmune attack against hypocretin-producing neurons. Despite the strong association with HLA class II, there is no evidence for CD4+ T-cell-mediated mechanism in narcolepsy. Since neurons express class I and not class II molecules, the final effector immune cells involved might include class I-restricted CD8+ T-cells. Methods: HLA class I (A, B, and C) and II (DQB1) genotypes were analyzed in 944 European narcolepsy with cataplexy patients and in 4,043 control subjects matched by country of origin. All patients and controls were DQB1*06:02 positive and class I associations were conditioned on DQB1 alleles. Results: HLA-A*11:01 (OR = 1.49 [1.18–1.87] P = 7.0*10−4), C*04:01 (OR = 1.34 [1.10–1.63] P = 3.23*10−3), and B*35:01 (OR = 1.46 [1.13–1.89] P = 3.64*10−3) were associated with susceptibility to narcolepsy. Analysis of polymorphic class I amino-acids revealed even stronger associations with key antigen-binding residues HLA-A-Tyr9 (OR = 1.32 [1.15–1.52] P = 6.95*10−5) and HLA-C-Ser11 (OR = 1.34 [1.15–1.57] P = 2.43*10−4). Conclusions: Our findings provide a genetic basis for increased susceptibility to infectious factors or an immune cytotoxic mechanism in narcolepsy, potentially targeting hypocretin neurons. Citation: Tafti M, Lammers GJ, Dauvilliers Y, Overeem S, Mayer G, Nowak J, Pfister C, Dubois V, Eliaou JF, Eberhard HP, Liblau R, Wierzbicka A, Geisler P, Bassetti CL, Mathis J, Lecendreux M, Khatami R, Heinzer R, Haba-Rubio J, Feketeova E, Baumann CR, Kutalik Z, Tiercy JM. Narcolepsy-associated HLA class I alleles implicate cell-mediated cytotoxicity. SLEEP 2016;39(3):581–587. PMID:26518595

  20. Combined use of anti-ErbB monoclonal antibodies and erlotinib enhances antibody-dependent cellular cytotoxicity of wild-type erlotinib-sensitive NSCLC cell lines

    Directory of Open Access Journals (Sweden)

    Cavazzoni Andrea

    2012-12-01

    Full Text Available Abstract Background The epidermal growth factor receptor (EGFR is an established target for anti-cancer treatment in different tumour types. Two different strategies have been explored to inhibit this pivotal molecule in epithelial cancer development: small molecules TKIs and monoclonal antibodies. ErbB/HER-targeting by monoclonal antibodies such as cetuximab and trastuzumab or tyrosine-kinase inhibitors as gefitinib or erlotinib has been proven effective in the treatment of advanced NSCLC. Results In this study we explored the potential of combining either erlotinib with cetuximab or trastuzumab to improve the efficacy of EGFR targeted therapy in EGFR wild-type NSCLC cell lines. Erlotinib treatment was observed to increase EGFR and/or HER2 expression at the plasma membrane level only in NSCLC cell lines sensitive to the drug inducing protein stabilization. The combined treatment had marginal effect on cell proliferation but markedly increased antibody-dependent, NK mediated, cytotoxicity in vitro. Moreover, in the Calu-3 xenograft model, the combination significantly inhibited tumour growth when compared with erlotinib and cetuximab alone. Conclusion Our results indicate that erlotinib increases surface expression of EGFR and/or HER2 only in EGFR-TKI sensitive NSCLC cell lines and, in turns, leads to increased susceptibility to ADCC both in vitro and in a xenograft models. The combination of erlotinib with monoclonal antibodies represents a potential strategy to improve the treatment of wild-type EGFR NSCLC patients sensitive to erlotinib.

  1. Antitumor activity of chLpMab-2, a human-mouse chimeric cancer-specific antihuman podoplanin antibody, via antibody-dependent cellular cytotoxicity.

    Science.gov (United States)

    Kaneko, Mika K; Yamada, Shinji; Nakamura, Takuro; Abe, Shinji; Nishioka, Yasuhiko; Kunita, Akiko; Fukayama, Masashi; Fujii, Yuki; Ogasawara, Satoshi; Kato, Yukinari

    2017-04-01

    Human podoplanin (hPDPN), a platelet aggregation-inducing transmembrane glycoprotein, is expressed in different types of tumors, and it binds to C-type lectin-like receptor 2 (CLEC-2). The overexpression of hPDPN is involved in invasion and metastasis. Anti-hPDPN monoclonal antibodies (mAbs) such as NZ-1 have shown antitumor and antimetastatic activities by binding to the platelet aggregation-stimulating (PLAG) domain of hPDPN. Recently, we developed a novel mouse anti-hPDPN mAb, LpMab-2, using the cancer-specific mAb (CasMab) technology. In this study we developed chLpMab-2, a human-mouse chimeric anti-hPDPN antibody, derived from LpMab-2. chLpMab-2 was produced using fucosyltransferase 8-knockout (KO) Chinese hamster ovary (CHO)-S cell lines. By flow cytometry, chLpMab-2 reacted with hPDPN-expressing cancer cell lines including glioblastomas, mesotheliomas, and lung cancers. However, it showed low reaction with normal cell lines such as lymphatic endothelial and renal epithelial cells. Moreover, chLpMab-2 exhibited high antibody-dependent cellular cytotoxicity (ADCC) against PDPN-expressing cells, despite its low complement-dependent cytotoxicity. Furthermore, treatment with chLpMab-2 abolished tumor growth in xenograft models of CHO/hPDPN, indicating that chLpMab-2 suppressed tumor development via ADCC. In conclusion, chLpMab-2 could be useful as a novel antibody-based therapy against hPDPN-expressing tumors. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  2. Separation of cell-dependent antibody (CDA) and inhibitory antibody by protein-A affinity chromatography and the effect of fractions on antibody-dependent cellular cytotoxicity (ADCC).

    Science.gov (United States)

    Sato, N; Yabuki, Y; Toh, K; Ishii, Y; Kikuchi, K

    1979-01-01

    The nature of cell-dependent antibody (CDA) and the mechanism of inhibition of antibody-dependent cellular cytotoxicity (ADCC) were studied in the ADCC assay system in which culture cells of methylcholanthrene-induced rat fibrosarcoma (KMT-50) were used as target cells, xenogeneic antiserum (rabbit anti-KMT-50) as the CDA, and human peripheral blood leucocytes (PBL) as effector cells, respectively. By using protein-A Sepharose CL-4B affinity column chromatography of rabbit anti-KMT-50 serum, CDA was shown to bind protein A. Complement dependent-cytotoxicity (CDC), however, was demonstrated in both the adsorbed fraction (eluate) and the non-adsorbed fraction (effluent) to protein A from the same affinity column chromatography. These data confirmed that CDA was IgG with an intact Fc portion. Inhibition of ADCC occurred by pretreatment of effector cells with rabbit anti-effector (human PBL) serum even with extremely small amounts of antiserum. Such inhibition was demonstrated with the eluate but not with the effluent from protein-A Sepharose CL-4B affinity column chromatography of rabbit anti-effector serum. F(ab')2 fragments of the same eluate (IgG) did not inhibit the ADCC activity. These data showed that the inhibition of ADCC was induced by the blocking of Fc receptors of effector cells with the Fc portions of IgG in anti-effector serum. The data obtained indicate the usefulness of protein A in separation and analysis of CDA and in investigation of the inhibitory mechanisms of ADCC. Images Figure 2 PMID:437836

  3. ChLpMab-23: Cancer-Specific Human-Mouse Chimeric Anti-Podoplanin Antibody Exhibits Antitumor Activity via Antibody-Dependent Cellular Cytotoxicity.

    Science.gov (United States)

    Kaneko, Mika K; Nakamura, Takuro; Kunita, Akiko; Fukayama, Masashi; Abe, Shinji; Nishioka, Yasuhiko; Yamada, Shinji; Yanaka, Miyuki; Saidoh, Noriko; Yoshida, Kanae; Fujii, Yuki; Ogasawara, Satoshi; Kato, Yukinari

    2017-06-01

    Podoplanin is expressed in many cancers, including oral cancers and brain tumors. The interaction between podoplanin and its receptor C-type lectin-like receptor 2 (CLEC-2) has been reported to be involved in cancer metastasis and tumor malignancy. We previously established many monoclonal antibodies (mAbs) against human podoplanin using the cancer-specific mAb (CasMab) technology. LpMab-23 (IgG 1 , kappa), one of the mouse anti-podoplanin mAbs, was shown to be a CasMab. However, we have not shown the usefulness of LpMab-23 for antibody therapy against podoplanin-expressing cancers. In this study, we first determined the minimum epitope of LpMab-23 and revealed that Gly54-Leu64 peptide, especially Gly54, Thr55, Ser56, Glu57, Asp58, Arg59, Tyr60, and Leu64 of podoplanin, is a critical epitope of LpMab-23. We further produced human-mouse chimeric LpMab-23 (chLpMab-23) and investigated whether chLpMab-23 exerts antibody-dependent cellular cytotoxicity (ADCC) and antitumor activity. In flow cytometry, chLpMab-23 showed high sensitivity against a podoplanin-expressing glioblastoma cell line, LN319, and an oral cancer cell line, HSC-2. chLpMab-23 also showed ADCC activity against podoplanin-expressing CHO cells (CHO/podoplanin). In xenograft models with HSC-2 and CHO/podoplanin, chLpMab-23 exerts antitumor activity using human natural killer cells, indicating that chLpMab-23 could be useful for antibody therapy against podoplanin-expressing cancers.

  4. Effects of ADAM10 and ADAM17 Inhibitors on Natural Killer Cell Expansion and Antibody-dependent Cellular Cytotoxicity Against Breast Cancer CellsIn Vitro.

    Science.gov (United States)

    Pham, Dang-Huan; Kim, Ju-Sun; Kim, Sang-Ki; Shin, Dong-Jun; Uong, Nguyen-Thanh-Tung; Hyun, Hoon; Yoon, Mee Sun; Kang, Sin Jae; Ryu, Young Jae; Cho, Jin Seong; Yoon, Jung Han; Lee, Ji Shin; Cho, Duck; Lee, Soo-Hyeon; Park, Min Ho

    2017-10-01

    The inhibition of a disintegrin and metalloproteinase (ADAM) has the potential to become a novel approach for natural killer (NK) cell-based cancer immunotherapy. Thus, the aim of this study was to investigate the influence of ADAM10 and ADAM17 inhibitors on expanded NK cell to enhance antibody-dependent cellular cytotoxicity (ADCC) in breast cancer cell lines. NK cells were expanded in medium supplemented with an ADAM10 or ADAM17 inhibitor to prevent the shedding of soluble CD16/FcγRIII. The expression level of CD16 and production of interferon-gamma (IFN-γ) was detected by flow cytometry using specific antibodies. ADCC activity of expanded NK cells was estimated in trastuzumab treated breast cancer cell lines such as MCF-7, MDA-MB-231, SKBR3, and BT-474 cells. The ADAM17 inhibitor increased the purity of expanded NK cells to 90% after 14 days at 5 and 10 μM in vitro (p=0.043). However, the expansion rate of NK cells was decreased at 10 μM of the ADAM 17 inhibitor (p=0.043). Inhibition of ADAM10 suppressed the expansion of NK cells, although the NK purity was increased at 1 μM of the inhibitor. The expression of CD16 was significantly increased at 1 and 5 μM of the ADAM17 inhibitor (p=0.046, 0.028, respectively) during the culturing period. Inhibition of ADAM10 reduced the expression of CD16 on NK cells. The cytotoxic activity of the ADAM17 inhibitor treated NK cells against MCF-7 (p=0.039) and BT-474 (p=0.027) cells was significantly elevated. The ADCC activity of NK cells treated with 5 μM of ADAM17 inhibitor was significantly increased against SKBR-3 and BT-474 (p=0.027). Inhibition of ADAM17 increased the production of IFN-γ in expanded NK cells. The inhibition of ADAM17 enhanced the purity of expanded NK cells and the ADCC activity of these cells against trastuzumab treated breast cancer cell lines. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  5. Au@Pt nanoparticles as catalase mimics to attenuate tumor hypoxia and enhance immune cell-mediated cytotoxicity

    Science.gov (United States)

    Liang, Hong; Wu, Ying; Ou, Xiang-Yu; Li, Jing-Ying; Li, Juan

    2017-11-01

    Hypoxic tumor microenvironment (TME) is closely linked to tumor progression, heterogeneity and immune suppression. Therefore, the development of effective methods to overcome hypoxia and substantially enhance the immunotherapy efficacy remains a desirable goal. Herein, we engineered a biocompatible Au core/Pt shell nanoparticles (Au@Pt NPs) to reoxygenate the TME by reacting with endogenous H2O2. Treatment with Au@Pt NPs appeared to improve oxygen in intracellular environments and decrease hypoxia-inducible factor-1α expression. Furthermore, the integration of high catalytic efficiency of Au@Pt NPs with cytokine-induced killer (CIK) cell immunotherapy, could lead to significantly improve the effect of CIK cell-mediated cytotoxicity. These results suggest great potential of Au@Pt NPs for regulation of the hypoxic TME and enhance immune cell mediated anti-tumor immunity.

  6. TCR down-regulation boosts T-cell-mediated cytotoxicity and protection against poxvirus infections

    DEFF Research Database (Denmark)

    Hansen, Ann Kathrine; Regner, Matthias; Bonefeld, Charlotte Menne

    2011-01-01

    Cytotoxic T (Tc) cells play a key role in the defense against virus infections. Tc cells recognize infected cells via the T-cell receptor (TCR) and subsequently kill the target cells by one or more cytotoxic mechanisms. Induction of the cytotoxic mechanisms is finely tuned by the activation signals...... from the TCR. To determine whether TCR down-regulation affects the cytotoxicity of Tc cells, we studied TCR down-regulation-deficient CD3¿LLAA mice. We found that Tc cells from CD3¿LLAA mice have reduced cytotoxicity due to a specific deficiency in exocytosis of lytic granules. To determine whether......-regulation critically increases Tc cell cytotoxicity and protection against poxvirus infection....

  7. High antibody-dependent cellular cytotoxicity responses are correlated with strong CD8 T cell viral suppressive activity but not with B57 status in HIV-1 elite controllers.

    Directory of Open Access Journals (Sweden)

    Olivier Lambotte

    Full Text Available The role of Antibody-dependent cellular cytotoxicity (ADCC responses in HIV-1 controllers is still unclear due to the heterogeneity of these patients. We analyzed 67 HIV-1 controllers and found significantly higher levels of ADCC antibodies in controllers versus viremic subjects (p = 0.017. Moreover, multivariate analysis revealed significantly higher ADCC titers in HLA B57- controllers compared to HLA-B57+ ones (p = 0.0086. These data suggest a role for ADCC in immune control of HIV, especially in HLA B57 negative controllers.

  8. Chimeric Anti-Human Podoplanin Antibody NZ-12 of Lambda Light Chain Exerts Higher Antibody-Dependent Cellular Cytotoxicity and Complement-Dependent Cytotoxicity Compared with NZ-8 of Kappa Light Chain.

    Science.gov (United States)

    Kaneko, Mika K; Abe, Shinji; Ogasawara, Satoshi; Fujii, Yuki; Yamada, Shinji; Murata, Takeshi; Uchida, Hiroaki; Tahara, Hideaki; Nishioka, Yasuhiko; Kato, Yukinari

    2017-02-01

    Podoplanin (PDPN), a type I transmembrane 36-kDa glycoprotein, is expressed not only in normal cells, such as renal epithelial cells (podocytes), lymphatic endothelial cells, and pulmonary type I alveolar cells, but also in cancer cells, including brain tumors and lung squamous cell carcinomas. Podoplanin activates platelet aggregation by binding to C-type lectin-like receptor-2 (CLEC-2) on platelets, and the podoplanin/CLEC-2 interaction facilitates blood/lymphatic vessel separation. We previously produced neutralizing anti-human podoplanin monoclonal antibody (mAb), clone NZ-1 (rat IgG 2a , lambda), which neutralizes the podoplanin/CLEC-2 interaction and inhibits platelet aggregation and cancer metastasis. Human-rat chimeric antibody, NZ-8, was previously developed using variable regions of NZ-1 and human constant regions of heavy chain (IgG 1 ) and light chain (kappa chain). Although NZ-8 showed high antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against human podoplanin-expressing cancer cells, the binding affinity of NZ-8 was lower than that of NZ-1. Herein, we produced a novel human-rat chimeric antibody, NZ-12, the constant regions of which consist of IgG 1 heavy chain and lambda light chain. Using flow cytometry, we demonstrated that the binding affinity of NZ-12 was much higher than that of NZ-8. Furthermore, ADCC and CDC activities of NZ-12 were significantly increased against glioblastoma cell lines (LN319 and D397) and lung cancer cell line (PC-10). These results suggested that NZ-12 could become a promising therapeutic antibody against podoplanin-expressing brain tumors and lung cancers.

  9. A novel antibody-dependent cellular cytotoxicity mechanism involved in defense against malaria requires costimulation of monocytes FcgammaRII and FcgammaRIII

    DEFF Research Database (Denmark)

    Jafarshad, Ali; Dziegiel, Morten Hanefeld; Lundquist, Rasmus

    2007-01-01

    Clinical experiments have shown that the Ab-dependent cell-mediated inhibition of Plasmodium falciparum is a major mechanism controlling malaria parasitemia and thereby symptoms. In this study, we demonstrate that a single merozoite per monocyte (MN) is sufficient to trigger optimal antiparasitic...

  10. Induction of cell-mediated immunity against mycobacterium tuberculosis using DNA vaccines encoding cytotoxic and helper T-cell epitopes of the 38-kilodalton protein

    NARCIS (Netherlands)

    Fonseca, DPAJ; Benaissa-Trouw, B; Kraaijeveld, CA; Snippe, H; Verheul, AFM

    Cell-mediated immune responses are crucial in the protection against tuberculosis. In this study, we constructed DNA vaccines encoding cytotoxic T lymphocytes (CTL) and T helper cell (Th) epitopes of the 38-kDa lipoglycoprotein of Mycobacterium tuberculosis and analyzed and compared their

  11. Cell-mediated cytotoxicity in rainbow trout, Oncorhynchus mykiss, infected with viral haemorrhagic septicaemia virus

    DEFF Research Database (Denmark)

    Utke, K.; Bergmann, S.; Lorenzen, Niels

    2007-01-01

    classical MHC class I locus Onmy-UBA is identical in the rainbow trout clone C25 and in the permanent rainbow trout cell line RTG-2. This enabled us to develop an assay to measure antiviral cytotoxicity in rainbow trout using a system of MHC class I-matched effector and target cells. Peripheral blood...... leucocytes (PBL) isolated from low dose viral haemorrhagic septicaemia virus (VHSV)-infected rainbow trout killed MHC class I-matched and later also xenogeneic MHC class I-mismatched VHSV-infected cells. When compared to PBL from uninfected control fish PBL from infected fish showed a higher transcriptional...

  12. Cell-mediated immunity to Plasmodium falciparum infection: evidence against the involvement of cytotoxic lymphocytes

    DEFF Research Database (Denmark)

    Theander, T G; Andersen, B J; Pedersen, B K

    1988-01-01

    by either SPag or PPD in the presence of immune serum. Studies on subpopulations of PBMC indicated that the inhibitory cells resided among the adherent cell fraction. Furthermore we tested PBMC for cytotoxic activity against P. falciparum-infected autologous or heterologous erythrocytes. Experiments were......Blood mononuclear cells (PBMC) recognizing soluble malaria antigens (SPag) are present in the peripheral blood of individuals clinically immune to malaria, and they proliferate after exposure to such antigens. To test whether these cells have effector activity against Plasmodium falciparum, we...... stimulated PBMC from malaria-immune donors by SPag and purified protein derivative (PPD) in culture for 7 days. The PBMC were then co-incubated with P. falciparum for 48 h, and parasitaemia was determined by microscopy. Parasite growth was only significantly impaired after incubation with PBMC stimulated...

  13. An Fc engineering approach that modulates antibody-dependent cytokine release without altering cell-killing functions.

    Science.gov (United States)

    Kinder, Michelle; Greenplate, Allison R; Strohl, William R; Jordan, Robert E; Brezski, Randall J

    2015-01-01

    Cytotoxic therapeutic monoclonal antibodies (mAbs) often mediate target cell-killing by eliciting immune effector functions via Fc region interactions with cellular and humoral components of the immune system. Key functions include antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC). However, there has been increased appreciation that along with cell-killing functions, the induction of antibody-dependent cytokine release (ADCR) can also influence disease microenvironments and therapeutic outcomes. Historically, most Fc engineering approaches have been aimed toward modulating ADCC, ADCP, or CDC. In the present study, we describe an Fc engineering approach that, while not resulting in impaired ADCC or ADCP, profoundly affects ADCR. As such, when peripheral blood mononuclear cells are used as effector cells against mAb-opsonized tumor cells, the described mAb variants elicit a similar profile and quantity of cytokines as IgG1. In contrast, although the variants elicit similar levels of tumor cell-killing as IgG1 with macrophage effector cells, the variants do not elicit macrophage-mediated ADCR against mAb-opsonized tumor cells. This study demonstrates that Fc engineering approaches can be employed to uncouple macrophage-mediated phagocytic and subsequent cell-killing functions from cytokine release.

  14. IFN-α augments natural killer-mediated antibody-dependent cellular cytotoxicity of HIV-1-infected autologous CD4+ T cells regardless of major histocompatibility complex class 1 downregulation.

    Science.gov (United States)

    Tomescu, Costin; Tebas, Pablo; Montaner, Luis J

    2017-03-13

    We have previously shown that IFN-α stimulation augments direct natural killer (NK) cell lysis of autologous CD4 primary T cells infected with certain HIV-1 isolates based upon major histocompatibility complex class 1 (MHC-1) downregulation capacity. Here, we investigated if antibody-dependent cellular cytotoxicity (ADCC) could trigger lysis of HIV-1 isolates that were resistant to direct NK lysis and if IFN-α prestimulation of NK cells could further enhance ADCC. Using broadly neutralizing monoclonal antibodies against gp120 (VRC01 or PGV04) or plasma from HIV-1-infected patients (ART-suppressed or elite controller) to trigger ADCC, we measured NK cell chromium release cytotoxicity against HIV-1-infected autologous CD4 primary T cells and NK cell CD107a degranulation against gp120-coated CD4 T cells. Total or NK-depleted peripheral blood mononuclear cells were used as effectors in the presence or absence of IFN-α prestimulation. Plasma from HIV-1-infected patients and monoclonal antibodies against gp120 could trigger NK-dependent ADCC lysis of viral isolates that were resistant to direct NK cell lysis following IFN-α stimulation. In contrast, viral isolates that exhibited potent MHC-I downregulation capacity could be lysed by NK cells through either IFN-α stimulated direct cytotoxicity or through ADCC. When utilized in combination, IFN-α prestimulation significantly augmented ADCC lysis of HIV-1-infected target cells and increased NK cell CD107a degranulation against gp120-coated ADCC targets (P cytotoxicity depending on MHC downregulation status.

  15. Effect of irradiation-induced intercellular adhesion molecule-1 expression on natural killer cell-mediated cytotoxicity toward human cancer cells.

    Science.gov (United States)

    Jeong, Jae-Uk; Uong, Tung Nguyen Thanh; Chung, Woong-Ki; Nam, Taek-Keun; Ahn, Sung-Ja; Song, Ju-Young; Kim, Sang-Ki; Shin, Dong-Jun; Cho, Eugene; Kim, Kyoung Won; Cho, Duck; Yoon, Mee Sun

    2018-03-20

    Irradiation enhances the adhesion between natural killer (NK) cells and target cells by up-regulating intercellular adhesion molecule-1 (ICAM-1) on target cells. Therefore, we investigated the effect of irradiation-induced ICAM-1 expression on human cancer cells on NK cell-mediated cytotoxicity. Expression levels of ICAM-1 on the target cell surface before and after irradiation of six human cancer cell lines (HL60, SKBR-3, T47D, HCT-116, U937 and U251) were analyzed by flow cytometry. Ex vivo expansion of NK cells from human peripheral blood mononuclear cells was performed by co-culture with irradiated K562 cells. The related adhesion molecule lymphocyte function-associated antigen 1 (LFA-1) on NK cells was analyzed by flow cytometry. An enzyme-linked immunosorbent assay was used to detect interferon-γ (IFN-γ), and WST-8 assays were performed to check NK cell cytotoxicity. Finally, blocking assays were performed using monoclonal antibodies against ICAM-1 or LFA-1. LFA-1 expression increased on NK cells after expansion (P cytotoxicity increased after irradiation of HL60 (P cytotoxicity against irradiated SKBR-3 (P cytotoxicity against irradiated HL60 (P cytotoxicity. Therefore, irradiation combined with NK cell therapy may improve the antitumor effects of NK cells. Copyright © 2018. Published by Elsevier Inc.

  16. Anti-Glycoprotein G Antibodies of Herpes Simplex Virus 2 Contribute to Complete Protection after Vaccination in Mice and Induce Antibody-Dependent Cellular Cytotoxicity and Complement-Mediated Cytolysis

    Directory of Open Access Journals (Sweden)

    Staffan Görander

    2014-11-01

    Full Text Available We investigated the role of antibodies against the mature portion of glycoprotein G (mgG-2 of herpes simplex virus 2 (HSV-2 in protective immunity after vaccination. Mice were immunized intramuscularly with mgG-2 and oligodeoxynucleotides containing two CpG motifs plus alum as adjuvant. All C57BL/6 mice survived and presented no genital or systemic disease. High levels of immunoglobulin G subclass 1 (IgG1 and IgG2 antibodies were detected and re-stimulated splenic CD4+ T cells proliferated and produced IFN-γ. None of the sera from immunized mice exhibited neutralization, while all sera exerted antibody-dependent cellular cytotoxicity (ADCC and complement-mediated cytolysis (ACMC activity. Passive transfer of anti-mgG-2 monoclonal antibodies, or immune serum, to naive C57BL/6 mice did not limit disease progression. Immunized B‑cell KO mice presented lower survival rate and higher vaginal viral titers, as compared with vaccinated B-cell KO mice after passive transfer of immune serum and vaccinated C57BL/6 mice. Sera from mice that were vaccinated subcutaneously and intranasally with mgG-2 presented significantly lower titers of IgG antibodies and lower ADCC and ACMC activity. We conclude that anti-mgG-2 antibodies were of importance to limit genital HSV‑2 infection. ADCC and ACMC activity are potentially important mechanisms in protective immunity, and could tentatively be evaluated in future animal vaccine studies and in clinical trials.

  17. Anti-glycoprotein g antibodies of herpes simplex virus 2 contribute to complete protection after vaccination in mice and induce antibody-dependent cellular cytotoxicity and complement-mediated cytolysis.

    Science.gov (United States)

    Görander, Staffan; Ekblad, Maria; Bergström, Tomas; Liljeqvist, Jan-Åke

    2014-11-12

    We investigated the role of antibodies against the mature portion of glycoprotein G (mgG-2) of herpes simplex virus 2 (HSV-2) in protective immunity after vaccination. Mice were immunized intramuscularly with mgG-2 and oligodeoxynucleotides containing two CpG motifs plus alum as adjuvant. All C57BL/6 mice survived and presented no genital or systemic disease. High levels of immunoglobulin G subclass 1 (IgG1) and IgG2 antibodies were detected and re-stimulated splenic CD4+ T cells proliferated and produced IFN-γ. None of the sera from immunized mice exhibited neutralization, while all sera exerted antibody-dependent cellular cytotoxicity (ADCC) and complement-mediated cytolysis (ACMC) activity. Passive transfer of anti-mgG-2 monoclonal antibodies, or immune serum, to naive C57BL/6 mice did not limit disease progression. Immunized B‑cell KO mice presented lower survival rate and higher vaginal viral titers, as compared with vaccinated B-cell KO mice after passive transfer of immune serum and vaccinated C57BL/6 mice. Sera from mice that were vaccinated subcutaneously and intranasally with mgG-2 presented significantly lower titers of IgG antibodies and lower ADCC and ACMC activity. We conclude that anti-mgG-2 antibodies were of importance to limit genital HSV‑2 infection. ADCC and ACMC activity are potentially important mechanisms in protective immunity, and could tentatively be evaluated in future animal vaccine studies and in clinical trials.

  18. Glycoengineered Monoclonal Antibodies with Homogeneous Glycan (M3, G0, G2, and A2 Using a Chemoenzymatic Approach Have Different Affinities for FcγRIIIa and Variable Antibody-Dependent Cellular Cytotoxicity Activities.

    Directory of Open Access Journals (Sweden)

    Masaki Kurogochi

    Full Text Available Many therapeutic antibodies have been developed, and IgG antibodies have been extensively generated in various cell expression systems. IgG antibodies contain N-glycans at the constant region of the heavy chain (Fc domain, and their N-glycosylation patterns differ during various processes or among cell expression systems. The Fc N-glycan can modulate the effector functions of IgG antibodies, such as antibody-dependent cellular cytotoxicity (ADCC and complement dependent cytotoxicity (CDC. To control Fc N-glycans, we performed a rearrangement of Fc N-glycans from a heterogeneous N-glycosylation pattern to homogeneous N-glycans using chemoenzymatic approaches with two types of endo-β-N-acetyl glucosaminidases (ENG'ases, one that works as a hydrolase to cleave all heterogeneous N-glycans, another that is used as a glycosynthase to generate homogeneous N-glycans. As starting materials, we used an anti-Her2 antibody produced in transgenic silkworm cocoon, which consists of non-fucosylated pauci-mannose type (Man2-3GlcNAc2, high-mannose type (Man4-9GlcNAc2, and complex type (Man3GlcNAc3-4 N-glycans. As a result of the cleavage of several ENG'ases (endoS, endoM, endoD, endoH, and endoLL, the heterogeneous glycans on antibodies were fully transformed into homogeneous-GlcNAc by a combination of endoS, endoD, and endoLL. Next, the desired N-glycans (M3; Man3GlcNAc1, G0; GlcNAc2Man3GlcNAc1, G2; Gal2GlcNAc2Man3GlcNAc1, A2; NeuAc2Gal2GlcNAc2Man3GlcNAc1 were transferred from the corresponding oxazolines to the GlcNAc residue on the intact anti-Her2 antibody with an ENG'ase mutant (endoS-D233Q, and the glycoengineered anti-Her2 antibody was obtained. The binding assay of anti-Her2 antibody with homogenous N-glycans with FcγRIIIa-V158 showed that the glycoform influenced the affinity for FcγRIIIa-V158. In addition, the ADCC assay for the glycoengineered anti-Her2 antibody (mAb-M3, mAb-G0, mAb-G2, and mAb-A2 was performed using SKBR-3 and BT-474 as target

  19. 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.

  20. Comprehensive Cross-Clade Characterization of Antibody-Mediated Recognition, Complement-Mediated Lysis, and Cell-Mediated Cytotoxicity of HIV-1 Envelope-Specific Antibodies toward Eradication of the HIV-1 Reservoir.

    Science.gov (United States)

    Mujib, Shariq; Liu, Jun; Rahman, A K M Nur-Ur; Schwartz, Jordan A; Bonner, Phil; Yue, Feng Yun; Ostrowski, Mario A

    2017-08-15

    Immunotherapy with passive administration of broadly neutralizing HIV-1 envelope-specific antibodies (bnAbs) in the setting of established infection in vivo has yielded mixed results. The contribution of different antibodies toward the direct elimination of infected cells is poorly understood. In this study, we determined the ability of 12 well-characterized anti-HIV-1 neutralizing antibodies to recognize and eliminate primary CD4 T cells infected with HIV-1 belonging to clades A, B, C, and D, via antibody-dependent complement-mediated lysis (ADCML) and antibody-dependent cell-mediated cytotoxicity (ADCC), in vitro We further tested unique combinations of these antibodies to determine the optimal antibody cocktails to be tested in future clinical trials. We report that antibody binding to infected CD4 T cells is highly variable and correlates with ADCML and ADCC processes. Particularly, antibodies targeting the envelope glycan shield (2G12) and V1/V2 site (PG9, PG16, and PGT145) are best at recognizing HIV-1-infected CD4 T cells. However, only PG9 and PG16 and their combinations with other bnAbs sufficiently induced the elimination of HIV-1-infected CD4 T cells by ADCML, ADCC, or both. Notably, CD4 binding site antibodies VRC01, 3BNC117, and NIH45-46 G54W did not exhibit recognition of infected cells and were unable to induce their killing. Future trials geared toward the development of a cure for HIV/AIDS should incorporate V1/V2 antibodies for maximal clearance of infected cells. With the use of only primary immune cells, we conducted a comprehensive cross-clade physiological analysis to aid the direction of antibodies as therapeutics toward the development of a cure for HIV/AIDS. IMPORTANCE Several antibodies capable of neutralizing the majority of circulating HIV-1 strains have been identified to date and have been shown to prevent infection in animal models. However, the use of combinations of such broadly neutralizing antibodies (bnAbs) for the treatment and

  1. Cell-mediated immunity to herpes simplex in humans: lymphocyte cytotoxicity measured by 51Cr release from infected cells

    International Nuclear Information System (INIS)

    Russell, A.S.; Percy, J.S.; Kovithavongs, T.

    1975-01-01

    We assessed cell-mediated immunity to herpes simplex virus type 1 antigen in patients suffering from recurrent cold sores and in a series of healthy controls. Paradoxically, all those subject to recurrent herpetic infections had, without exception, evidence of cell-mediated immunity to herpes antigens. This was demonstrated by lymphocyte transformation and specific 51 Cr release from infected human amnion cells after incubation with peripheral blood mononuclear cells. Where performed, skin tests with herpes antigen were also positive. In addition, serum from these patients specifically sensitized herpes virus-infected cells to killing by nonimmune, control mononuclear cells. These tests were negative in the control patients except in a few cases, and it is suggested that these latter may be the asymptomatic herpes virus carriers previously recognized or that they may have experienced a genital infection. (U.S.)

  2. T cell-mediated cytotoxicity against p53-protein derived peptides in bulk and limiting dilution cultures of healthy donors

    DEFF Research Database (Denmark)

    Röpke, M; Regner, M; Claesson, M H

    1995-01-01

    -I restricted epitopes for T cell recognition and p53-derived peptides have been suggested as targets for tumour-specific cytotoxic T lymphocytes (CTL). Our primary aim was to estimate the frequencies of p53-peptide reactive CTL precursors (CTLp) in peripheral blood from healthy young individuals. We selected...

  3. Inhibition of clone formation as an assay for T cell-mediated cytotoxicity: short-term kinetics and comparison with 51Cr release

    International Nuclear Information System (INIS)

    Lees, R.K.; MacDonald, H.R.; Sinclair, N.R.; University of Western Ontario London

    1977-01-01

    The short-term kinetics of T cell-mediated cytotoxicity was investigated using a cloning inhibition assay. Murine cytotoxic thymus-derived lymphocytes generated in vitro in mixed leukocyte cultures were incubated for various periods of time at 37degC with allogeneic mastocytoma target cells. The mixtures were then plated in soft agar, and mastocytoma clone formation was assessed after 5-7 days incubation. Using this technique, it was demonstrated that events leading to the loss of cloning ability could be detected after 1-3 min incubation at 37degC, and after 20-30 min, 95% of the clone forming cells had been inactivated. When these results were compared directly with those obtained using the conventional 51 Cr-release assay, it was found that the events leading to loss of cloning ability occurred more rapidly than indicated by the isotope assay. However, a modification of the 51 Cr-release assay involving EDTA addition gave comparable result to the cloning inhibition assay. These results raise the possibility that the events leading to 51 Cr-release of tumor target cells may be related in time to those leading to the loss of cloning ability

  4. From sabotage to camouflage: viral evasion of cytotoxic T lymphocyte and natural killer cell-mediated immunity.

    Science.gov (United States)

    Farrell, H E; Davis-Poynter, N J

    1998-06-01

    The outcome of a virus infection is strongly influenced by interactions between host immune defences and virus 'antidefence' mechanisms. For many viruses, their continued survival depends on the speed of their attack:their capacity to replicate and transmit to uninfected hosts prior to their elimination by an effective immune response. In contrast, the success of persistent viruses lies in their capacity for immunological subterfuge: the evasion of host defence mechanism by either mutation (covered elsewhere in this issue, by Gould and Bangham, pp. 331-338) or interference with the action of host cellular proteins that are important components of the immune response. This review will focus on the strategies employed by persistent viruses against two formidable host defences against virus infection: the CD8+ cytotoxic T lymphocyte (CTL) and natural killer (NK) cell responses.

  5. Genes related to cell-mediated cytotoxicity and interferon response are induced in the retina of European sea bass upon intravitreal infection with nodavirus.

    Science.gov (United States)

    Valero, Yulema; Boughlala, Bassima; Arizcun, Marta; Patel, Sonal; Fiksdal, Ingrid U; Esteban, M Ángeles; De Juan, Joaquín; Meseguer, José; Chaves-Pozo, Elena; Cuesta, Alberto

    2018-03-01

    Viral diseases are responsible for high rates of mortality and subsequent economic losses in modern aquaculture. The nervous necrosis virus (NNV) produces viral encephalopathy and retinopathy (VER), which affects the central nervous system, is considered one of the most serious viral diseases in marine aquaculture. Although some studies have localized NNV in the retina cells, none has dealt with immunity in the retina. Thus, for the first time, we intravitreally infected healthy specimens of European sea bass (Dicentrarchus labrax) with NNV with the aim of characterizing the immune response in the retina. Ultrastructural analysis detected important retinal injuries and structure degradation, including pycnosis, hydropic degeneration and vacuolization in some cell layers as well as myelin sheaths in the optic nerve fibres. Immunohistochemistry demonstrated that NNV replicated in the eyes. Regarding retinal immunity, NNV infection elicited the transcription of genes encoding proteins involved in the interferon (IFN) and cell-mediated cytotoxicity (CMC) responses as well as B and T cell markers, demonstrating that viral replication influences innate and adaptive responses. Further studies are needed to understand the retina immunity and whether the main retinal function, vision, is affected by nodavirus. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. CD4+ T cell-mediated cytotoxicity is associated with MHC class II expression on malignant CD19+ B cells in diffuse large B cell lymphoma.

    Science.gov (United States)

    Zhou, Yong; Zha, Jie; Lin, Zhijuan; Fang, Zhihong; Zeng, Hanyan; Zhao, Jintao; Luo, Yiming; Li, Zhifeng; Xu, Bing

    2018-01-15

    Diffuse large B cell lymphoma (DLBCL) is a common B cell malignancy with approximately 30% of patients present relapsed or refractory disease after first-line therapy. Research of further treatment options is needed. Cytotoxic CD4 + T cells express cytolytic molecules and have potential antitumor function. Here, we showed that the CD19 + cells from DLBCL patients presented significantly reduced expression of MHC II molecules than those from healthy controls. Three years after the first-line treatment, patients that presented relapsed disease had significantly lower MHC II expression on their CD19 + cells than patients who did not show recurrence. Examining cytotoxic CD4 + T cells show that DLBCL patients presented significantly elevated frequencies of granzyme A-, granzyme B-, and/or perforin-expressing cytotoxic CD4 + T cells. Also, frequency of cytotoxic CD4 + T cells in DLBCL patients was positively correlated with the MHC II expression level. Subsequently, the cytotoxic potential of CD4 + T cells against autologous CD19 + cells was investigated. We found that the cytotoxic potential of CD4 + T cells was highest in MHC II-high, intermediate in MHC II-mid, and lowest in MHC II-low patients. The percentage of MHC II-expressing viable CD19 + cells presented a significant reduction after longer incubation with cytotoxic CD4 + T cells, suggesting that cytotoxic CD4 + T cells preferentially eliminated MHC II-expressing CD19 + cells. Blocking MHC II on CD19 + cells significantly reduced the cytolytic capacity of CD4 + T cells. Despite these discoveries, the frequency of cytotoxic CD4 + T cells did not predict the clinical outcome of DLBCL patients. Together, these results demonstrated that cytotoxic CD4 + T cells presented an MHC II-dependent cytotoxic potential against autologous CD19 + cells and could potentially represent a future treatment option for DLBCL. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. A marked reduction in priming of cytotoxic CD8+ T cells mediated by stress-induced glucocorticoids involves multiple deficiencies in cross-presentation by dendritic cells.

    Science.gov (United States)

    Hunzeker, John T; Elftman, Michael D; Mellinger, Jennifer C; Princiotta, Michael F; Bonneau, Robert H; Truckenmiller, Mary E; Norbury, Christopher C

    2011-01-01

    Protracted psychological stress elevates circulating glucocorticoids, which can suppress CD8(+) T cell-mediated immunity, but the mechanisms are incompletely understood. Dendritic cells (DCs), required for initiating CTL responses, are vulnerable to stress/corticosterone, which can contribute to diminished CTL responses. Cross-priming of CD8(+) T cells by DCs is required for initiating CTL responses against many intracellular pathogens that do not infect DCs. We examined the effects of stress/corticosterone on MHC class I (MHC I) cross-presentation and priming and show that stress/corticosterone-exposed DCs have a reduced ability to cross-present OVA and activate MHC I-OVA(257-264)-specific T cells. Using a murine model of psychological stress and OVA-loaded β(2)-microglobulin knockout "donor" cells that cannot present Ag, DCs from stressed mice induced markedly less Ag-specific CTL proliferation in a glucocorticoid receptor-dependent manner, and endogenous in vivo T cell cytolytic activity generated by cross-presented Ag was greatly diminished. These deficits in cross-presentation/priming were not due to altered Ag donation, Ag uptake (phagocytosis, receptor-mediated endocytosis, or fluid-phase uptake), or costimulatory molecule expression by DCs. However, proteasome activity in corticosterone-treated DCs or splenic DCs from stressed mice was partially suppressed, which limits formation of antigenic peptide-MHC I complexes. In addition, the lymphoid tissue-resident CD11b(-)CD24(+)CD8α(+) DC subset, which carries out cross-presentation/priming, was preferentially depleted in stressed mice. At the same time, CD11b(-)CD24(+)CD8α(-) DC precursors were increased, suggesting a block in development of CD8α(+) DCs. Therefore, glucocorticoid-induced changes in both the cellular composition of the immune system and intracellular protein degradation contribute to impaired CTL priming in stressed mice.

  8. HER2/HER3 signaling regulates NK cell-mediated cytotoxicity via MHC class I chain-related molecule A and B expression in human breast cancer cell lines.

    Science.gov (United States)

    Okita, Riki; Mougiakakos, Dimitrios; Ando, Takashi; Mao, Yumeng; Sarhan, Dhifaf; Wennerberg, Erik; Seliger, Barbara; Lundqvist, Andreas; Mimura, Kousaku; Kiessling, Rolf

    2012-03-01

    Overexpression of the receptor tyrosine kinases HER2 and HER3 is associated with a poor prognosis in several types of cancer. Presently, HER2- as well as HER3-targeted therapies are in clinical practice or evaluated within clinical trials, including treatment with mAbs mediating growth inhibition and/or activation of Ab-induced innate or adaptive cellular immunity. A better understanding of how HER2/HER3 signaling in tumors influences cellular immune mechanisms is therefore warranted. In this study, we demonstrate that HER2/HER3 signaling regulates the expression of MHC class I-related chain A and B (MICA and MICB) in breast cancer cell lines. The MICA and MICB (MICA/B) molecules act as key ligands for the activating receptor NK group 2, member D (NKG2D) and promote NK cell-mediated recognition and cytolysis. Genetic silencing of HER3 but not HER2 downregulated the expression of MICA/B, and HER3 overexpression significantly enhanced MICA expression. Among the major pathways activated by HER2/HER3 signaling, the PI3K/AKT pathway was shown to predominantly regulate MICA/B expression. Treatment with the HER3-specific ligand neuregulin 1β promoted the expression in a process that was antagonized by pharmacological and genetic interference with HER3 but not by the ataxia-telangiectasia-mutated (ATM) and ATM and Rad3-related protein kinases inhibitor caffeine. These observations further emphasize that HER2/HER3 signaling directly, and not via genotoxic stress, regulates MICA/B expression. As anticipated, stimulating HER2/HER3 enhanced the NKG2D-MICA/B-dependent NK cell-mediated cytotoxicity. Taken together, we conclude that signaling via the HER2/HER3 pathway in breast carcinoma cell lines may lead to enhanced NKG2D-MICA/B recognition by NK cells and T cells.

  9. Monoclonal Antibodies, Derived from Humans Vaccinated with the RV144 HIV Vaccine Containing the HVEM Binding Domain of Herpes Simplex Virus (HSV) Glycoprotein D, Neutralize HSV Infection, Mediate Antibody-Dependent Cellular Cytotoxicity, and Protect Mice from Ocular Challenge with HSV-1.

    Science.gov (United States)

    Wang, Kening; Tomaras, Georgia D; Jegaskanda, Sinthujan; Moody, M Anthony; Liao, Hua-Xin; Goodman, Kyle N; Berman, Phillip W; Rerks-Ngarm, Supachai; Pitisuttithum, Punnee; Nitayapan, Sorachai; Kaewkungwal, Jaranit; Haynes, Barton F; Cohen, Jeffrey I

    2017-10-01

    The RV144 HIV vaccine trial included a recombinant HIV glycoprotein 120 (gp120) construct fused to a small portion of herpes simplex virus 1 (HSV-1) glycoprotein D (gD) so that the first 40 amino acids of gp120 were replaced by the signal sequence and the first 27 amino acids of the mature form of gD. This region of gD contains most of the binding site for HVEM, an HSV receptor important for virus infection of epithelial cells and lymphocytes. RV144 induced antibodies to HIV that were partially protective against infection, as well as antibodies to HSV. We derived monoclonal antibodies (MAbs) from peripheral blood B cells of recipients of the RV144 HIV vaccine and showed that these antibodies neutralized HSV-1 infection in cells expressing HVEM, but not the other major virus receptor, nectin-1. The MAbs mediated antibody-dependent cellular cytotoxicity (ADCC), and mice that received the MAbs and were then challenged by corneal inoculation with HSV-1 had reduced eye disease, shedding, and latent infection. To our knowledge, this is the first description of MAbs derived from human recipients of a vaccine that specifically target the HVEM binding site of gD. In summary, we found that monoclonal antibodies derived from humans vaccinated with the HVEM binding domain of HSV-1 gD (i) neutralized HSV-1 infection in a cell receptor-specific manner, (ii) mediated ADCC, and (iii) reduced ocular disease in virus-infected mice. IMPORTANCE Herpes simplex virus 1 (HSV-1) causes cold sores and neonatal herpes and is a leading cause of blindness. Despite many trials, no HSV vaccine has been approved. Nectin-1 and HVEM are the two major cellular receptors for HSV. These receptors are expressed at different levels in various tissues, and the role of each receptor in HSV pathogenesis is not well understood. We derived human monoclonal antibodies from persons who received the HIV RV144 vaccine that contained the HVEM binding domain of HSV-1 gD fused to HIV gp120. These antibodies were

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

  11. Cytotoxic effects of Urtica dioica radix on human colon (HT29) and gastric (MKN45) cancer cells mediated through oxidative and apoptotic mechanisms.

    Science.gov (United States)

    Ghasemi, S; Moradzadeh, M; Mousavi, S H; Sadeghnia, H R

    2016-10-15

    Defects in the apoptotic pathways are responsible for both the colorectal cancer pathogenesis and resistance to therapy. In this study, we examined the level of cellular oxidants, cytotoxicity and apoptosis induced by hydroalcoholic extract of U. dioica radix (0-2000 µg/mL) and oxaliplatin (0-1000 µg/mL, as positive control) in human gastric (MKN45) and colon (HT29) cancer, as well as normal human foreskin fibroblast (HFF) cells. Exposure to U. dioica or oxaliplatin showed a concentration dependent suppression in cell survival with IC50 values of 24.7, 249.9 and 857.5 µg/mL for HT29, MKN45 and HFF cells after 72 h treatment, respectively. ROS formation and lipid peroxidation were also concentration-dependently increased following treatment with U. dioica, similar to oxaliplatin. In addition, the number of apoptotic cells significantly increased concomitantly with concentration of U. dioica as compared with control cells, which is similar to oxaliplatin and serum-deprived cancer cells. In conclusion, the present study demonstrated that U. dioica inhibited proliferation of gastric and colorectal cancer cells while posing no significant toxic effect on normal cells. U. dioica not only increased levels of oxidants, but also induced concomitant increase of apoptosis. The precise signaling pathway by which U. dioica induce apoptosis needs further research.

  12. Behçet disease-associated MHC class I residues implicate antigen binding and regulation of cell-mediated cytotoxicity.

    Science.gov (United States)

    Ombrello, Michael J; Kirino, Yohei; de Bakker, Paul I W; Gül, Ahmet; Kastner, Daniel L; Remmers, Elaine F

    2014-06-17

    The HLA protein, HLA-B*51, encoded by HLA-B in MHC, is the strongest known genetic risk factor for Behçet disease (BD). Associations between BD and other factors within the MHC have been reported also, although strong regional linkage disequilibrium complicates their confident disentanglement from HLA-B*51. In the current study, we examined a combination of directly obtained and imputed MHC-region SNPs, directly obtained HLA-B locus types, and imputed classical HLA types with their corresponding polymorphic amino acid residues for association with BD in 1,190 cases and 1,257 controls. SNP mapping with logistic regression of the MHC identified the HLA-B/MICA region and the region between HLA-F and HLA-A as independently associated with BD (P MHC class I (MHC-I) amino acid residues, including anchor residues that critically define the selection and binding of peptides to MHC-I molecules, residues known to influence MHC-I-killer immunoglobulin-like receptor interactions, and a residue located in the signal peptide of HLA-B. The locations of these variants collectively implicate MHC-I peptide binding in the pathophysiology of BD. Furthermore, several lines of evidence suggest a role for altered regulation of cellular cytotoxicity in BD pathogenesis.

  13. Human recombinant anti-thyroperoxidase autoantibodies: in vitro cytotoxic activity on papillary thyroid cancer expressing TPO.

    Science.gov (United States)

    Rebuffat, S A; Morin, M; Nguyen, B; Castex, F; Robert, B; Péraldi-Roux, S

    2010-03-02

    Thyroid cancers are difficult to treat due to their limited responsiveness to chemo- and radiotherapy. There is thus a great interest in and a need for alternative therapeutic approaches. We studied the cytotoxic activity of anti-thyroperoxidase autoantibodies (anti-TPO aAbs, expressed in baculovirus/insect cell (B4) and CHO cells (B4') or purified from patients' sera) against a papillary thyroid cancer (NPA) cell line. Anti-TPO aAbs from patients' sera led to a partial destruction of NPA cell line by complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC) and exhibited an anti-proliferative activity. Comparison of the cytotoxic activity of anti-TPO aAbs shows that B4' induced an anti-proliferative effect and a better ADCC than B4, but a lower one than anti-TPO aAbs from patients' sera. Antibody-dependent cell-mediated cytotoxicity was increased when human peripheral blood mononuclear cells were used as effector cells, suggesting that FcgammaRs, CD64, CD32 and CD16 are involved. Indeed, anti-TPO aAbs from patients' sera, but not B4 and B4', exhibited CDC activity. These data indicate that anti-TPO aAbs display moderate ADCC and anti-proliferative activities on NPA cells; IgG glycosylation appears to be important for cytotoxic activity and ADCC efficiency depends on FcgammaR-bearing cells. Finally, recombinant human anti-TPO aAbs cannot yet be considered as an optimal tool for the development of a novel therapeutic approach for thyroid cancer.

  14. Antibody dependent cellular phagocytosis by macrophages is a novel mechanism of action of elotuzumab.

    Science.gov (United States)

    Kurdi, Ahmed T; Glavey, Siobhan V; Bezman, Natalie A; Jhatakia, Amy; Guerriero, Jennifer L; Manier, Salomon; Moschetta, Michele; Mishima, Yuji; Roccaro, Aldo; Detappe, Alexandre; Liu, Chia-Jen; Sacco, Antonio; Huynh, Daisy; Tai, Yu-Tzu; Robbins, Michael D; Azzi, Jamil; Ghobrial, Irene M

    2018-04-13

    Elotuzumab, a recently approved antibody for the treatment of multiple myeloma (MM), has been shown to stimulate Fcγ receptor (FcγR)-mediated antibody-dependent cellular cytotoxicity (ADCC) by natural killer (NK) cells towards myeloma cells. The modulatory effects of elotuzumab on other effector cells in the tumor microenvironment, however, has not been fully explored. Antibody dependent cellular phagocytosis (ADCP) is a mechanism by which macrophages contribute to anti-tumor potency of monoclonal antibodies. Herein, we studied the NK cell independent effect of elotuzumab on tumor associated macrophages (TAMs) using a xenograft tumor model deficient in NK and adaptive immune cells. We demonstrate significant anti-tumor efficacy of single agent elotuzumab in immunocompromised xenograft models of multiple myeloma, which is in part mediated by Fc-FcγR interaction of elotuzumab with macrophages. Elotuzumab is shown in this study to induce phenotypic activation of macrophages in-vivo and mediates ADCP of myeloma cells though a FcγR dependent manner in-vitro. Together, these findings propose a novel immune mediated mechanism by which elotuzumab exerts anti-myeloma activity and helps to provide rationale for combination therapies that can enhance macrophage activity. Copyright ©2018, American Association for Cancer Research.

  15. Modulating Cytotoxic Effector Functions by Fc Engineering to Improve Cancer Therapy.

    Science.gov (United States)

    Kellner, Christian; Otte, Anna; Cappuzzello, Elisa; Klausz, Katja; Peipp, Matthias

    2017-09-01

    In the last two decades, monoclonal antibodies have revolutionized the therapy of cancer patients. Although antibody therapy has continuously been improved, still a significant number of patients do not benefit from antibody therapy. Therefore, rational optimization of the antibody molecule by Fc engineering represents a major area of translational research to further improve this potent therapeutic option. Monoclonal antibodies are able to trigger a variety of effector mechanisms. Especially Fc-mediated effector functions such as antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement- dependent cytotoxicity (CDC) are considered important in antibody therapy of cancer. Novel mechanistic insights into the action of monoclonal antibodies allowed the development of various Fc engineering approaches to modulate antibodies' effector functions. Strategies in modifying the Fc glycosylation profile (Fc glyco-engineering) or approaches in engineering the protein backbone (Fc protein engineering) have been intensively evaluated. In the current review, Fc engineering strategies resulting in improved ADCC, ADCP and CDC activity are summarized and discussed.

  16. Contribution of NK cell education to both direct and anti-HIV-1 antibody-dependent NK cell functions.

    Science.gov (United States)

    Kristensen, Anne B; Kent, Stephen J; Parsons, Matthew S

    2018-03-07

    mediate antibody-dependent functions remain poorly defined. We now show that NK cell education determines the capacity of NK cells to exhibit anti-HIV-1 antibody-dependent activation and mediate antibody-dependent cellular cytotoxicity. These observations suggest the process of NK cell education could be of importance for understanding HIV-1 pathogenesis and designing immune-based prophylactics or therapeutics. Copyright © 2018 American Society for Microbiology.

  17. 2. Cell-mediatedImmunity

    Indian Academy of Sciences (India)

    Admin

    Cell-mediated Immunity sma hmed', Banishree Saha', nand Patwardhan°,. Shwetha Shivaprasad and Dipankar Nandis. Our immune system, by and large, does a fine job in protect- ing us from opportunistic and infectious microbes, potential carcinogens and allergens. It is therefore crucial to under- stand the organization ...

  18. Proteasome Inhibition Suppresses Dengue Virus Egress in Antibody Dependent Infection.

    Directory of Open Access Journals (Sweden)

    Milly M Choy

    2015-11-01

    Full Text Available The mosquito-borne dengue virus (DENV is a cause of significant global health burden, with an estimated 390 million infections occurring annually. However, no licensed vaccine or specific antiviral treatment for dengue is available. DENV interacts with host cell factors to complete its life cycle although this virus-host interplay remains to be fully elucidated. Many studies have identified the ubiquitin proteasome pathway (UPP to be important for successful DENV production, but how the UPP contributes to DENV life cycle as host factors remains ill defined. We show here that proteasome inhibition decouples infectious virus production from viral RNA replication in antibody-dependent infection of THP-1 cells. Molecular and imaging analyses in β-lactone treated THP-1 cells suggest that proteasome function does not prevent virus assembly but rather DENV egress. Intriguingly, the licensed proteasome inhibitor, bortezomib, is able to inhibit DENV titers at low nanomolar drug concentrations for different strains of all four serotypes of DENV in primary monocytes. Furthermore, bortezomib treatment of DENV-infected mice inhibited the spread of DENV in the spleen as well as the overall pathological changes. Our findings suggest that preventing DENV egress through proteasome inhibition could be a suitable therapeutic strategy against dengue.

  19. Functional cell mediated lympholysis I. Description of the assay

    International Nuclear Information System (INIS)

    Goeken, N.E.; Thompson, J.S.

    1981-01-01

    The anamnestic response by human bi-directional (BD) mixed lymphocyte cultures (MLC) to restimulation by cells of the original stimulating type is generally strikingly reduced as compared to that of standard one-way cultures. This difference was shown not to be related to a change in kinetics nor was it due to exhaustion of the media or soluble factors since fresh media did not ameliorate the effect nor were supernatants from BD cultures found to be suppressive. The relative inhibition was also not reversed by removal of the allogeneic cells by phenotype specific antiserum. Cytotoxic tests with donor and responder specific antisera revealed that the cells bearing that phenotype were dramatically reduced in BD as compared to one-way cultures. Thus, the diminished secondary response appears to be due to cytotoxic elimination of the responder cells. This allogeneic cytotoxicity is dependent on non-T, phagocytic, adherent cells. The phenomenon is called Functional Cell Mediated Lympholysis (F-CML). (author)

  20. Clustered Ergot Alkaloids Modulate Cell-mediated Cytotoxicity

    Czech Academy of Sciences Publication Activity Database

    Křen, Vladimír; Fišerová, Anna; Weignerová, Lenka; Stibor, I.; Halada, Petr; Přikrylová, Věra; Sedmera, Petr; Pospíšil, Miloslav

    2002-01-01

    Roč. 10, - (2002), s. 415-424 ISSN 0968-0896 R&D Projects: GA AV ČR IAA4020901; GA ČR GA310/98/0347 Institutional research plan: CEZ:AV0Z5020903 Keywords : clustered * ergot * alkaloids Subject RIV: EE - Microbiology, Virology Impact factor: 2.043, year: 2002

  1. FcγRII-binding Centyrins mediate agonism and antibody-dependent cellular phagocytosis when fused to an anti-OX40 antibody.

    Science.gov (United States)

    Zhang, Di; Whitaker, Brian; Derebe, Mehabaw G; Chiu, Mark L

    2018-04-01

    Immunostimulatory antibodies against the tumor necrosis factor receptors (TNFR) are emerging as promising cancer immunotherapies. The agonism activity of such antibodies depends on crosslinking to Fc gamma RIIB receptor (FcγRIIB) to enable the antibody multimerization that drives TNFR activation. Previously, Fc engineering was used to enhance the binding of such antibodies to Fcγ receptors. Here, we report the identification of Centyrins as alternative scaffold proteins with binding affinities to homologous FcγRIIB and FcγRIIA, but not to other types of Fcγ receptors. One Centyrin, S29, was engineered at distinct positions of an anti-OX40 SF2 antibody to generate bispecific and tetravalent molecules named as mAbtyrins. Regardless of the position of S29 on the SF2 antibody, SF2-S29 mAbtyrins could bind FcγRIIB and FcγRIIA specifically while maintaining binding to OX40 receptors. In a NFκB reporter assay, attachment of S29 Centyrin molecules at the C-termini, but not the N-termini, resulted in SF2 antibodies with increased agonism owing to FcγRIIB crosslinking. The mAbtyrins also showed agonism in T-cell activation assays with immobilized FcγRIIB and FcγRIIA, but this activity was confined to mAbtyrins with S29 specifically at the C-termini of antibody heavy chains. Furthermore, regardless of the position of the molecule, S29 Centyrin could equip an otherwise Fc-silent antibody with antibody-dependent cellular phagocytosis activity without affecting the antibody's intrinsic antibody-dependent cell-meditated cytotoxicity and complement-dependent cytotoxicity. In summary, the appropriate adoption FcγRII-binding Centyrins as functional modules represents a novel strategy to engineer therapeutic antibodies with improved functionalities.

  2. Effect of trastuzumab interchain disulfide bond cleavage on Fcγ receptor binding and antibody-dependent tumour cell phagocytosis.

    Science.gov (United States)

    Suzuki, Mami; Yamanoi, Ayaka; Machino, Yusuke; Ootsubo, Michiko; Izawa, Ken-ichi; Kohroki, Junya; Masuho, Yasuhiko

    2016-01-01

    The Fc domain of human IgG1 binds to Fcγ receptors (FcγRs) to induce effector functions such as phagocytosis. There are four interchain disulfide bonds between the H and L chains. In this study, the disulfide bonds within the IgG1 trastuzumab (TRA), which is specific for HER2, were cleaved by mild S-sulfonation or by mild reduction followed by S-alkylation with three different reagents. The cleavage did not change the binding activities of TRA to HER2-bearing SK-BR-3 cells. The binding activities of TRA to FcγRIIA and FcγRIIB were greatly enhanced by modification with mild reduction and S-alkylation with ICH2CONH2 or N-(4-aminophenyl) maleimide, while the binding activities of TRA to FcγRI and FcγRIIIA were decreased by any of the four modifications. However, the interchain disulfide bond cleavage by the different modifications did not change the antibody-dependent cell-mediated phagocytosis (ADCP) of SK-BR-3 cells by activated THP-1 cells. The order of FcγR expression levels on the THP-1 cells was FcγRII > FcγRI > FcγRIII and ADCP was inhibited by blocking antibodies against FcγRI and FcγRII. These results imply that the effect of the interchain disulfide bond cleavage on FcγRs binding and ADCP is dependent on modifications of the cysteine residues and the FcγR isotypes. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  3. Antibody-Dependent Enhancement of Dengue Virus Growth in Human Monocytes as a Risk Factor for Dengue Hemorrhagic Fever

    Science.gov (United States)

    1989-01-01

    Clamfication) Antibody-Dependent Enhancement of Dengue Virus Growth in Human Monocytes as a Risk Factor for Dengue Hemorrhagic Fever 𔃼 PERSONAL AjTHOR(S...FELD GROUP SUBGROUP Antibody-Dependent Enhancement of Dengue Virus Growth in Human Monocytes as a Risk Factor for Dengue Hemorrhagic Fever . 19...clinically diagnosed as dengue hemorrhagic fever . Antibody-dependent enhancement of virus growth was quantitated by measurement of virus yields in

  4. Antibody-dependent enhancement of dengue virus infection is inhibited by SA-17, a doxorubicin derivative

    NARCIS (Netherlands)

    Ayala Nunez, Vanesa; Jarupathirun, Patsaporn; Kaptein, Suzanne; Neyts, Johan; Smit, Jolanda

    2013-01-01

    Antibody-dependent enhancement (ADE) is thought to play a critical role in the exacerbation of dengue virus (DENV)-induced disease during a heterologous re-infection. Despite ADE's clinical impact, only a few antiviral compounds have been assessed for their anti-ADE activity. We reported earlier

  5. Antibody-dependent NK cell activation is associated with late kidney allograft dysfunction and the complement-independent alloreactive potential of donor-specific antibodies

    Directory of Open Access Journals (Sweden)

    Tristan Legris

    2016-08-01

    Full Text Available Although kidney transplantation remains the best treatment for end-stage renal failure, it is limited by chronic humoral aggression of the graft vasculature by donor-specific antibodies (DSAs. The complement-independent mechanisms that lead to the antibody-mediated rejection (ABMR of kidney allografts remain poorly understood. Increasing lines of evidence have revealed the relevance of natural killer (NK cells as innate immune effectors of antibody-dependent cellular cytotoxicity, but few studies have investigated their alloreactive potential in the context of solid organ transplantation. Our study aimed to investigate the potential contribution of the antibody-dependent alloreactive function of NK cells to kidney graft dysfunction. We first conducted an observational study to investigate whether the cytotoxic function of NK cells is associated with chronic allograft dysfunction. The NK-Cellular Humoral Activation Test (NK-CHAT was designed to evaluate the recipient and antibody-dependent reactivity of NK cells against allogeneic target cells. The release of CD107a/Lamp1+ cytotoxic granules, resulting from the recognition of rituximab-coated B cells by NK cells, was analyzed in 148 kidney transplant recipients (KTRs, mean graft duration: 6.2 years. Enhanced ADCC responsiveness was associated with reduced graft function and identified as an independent risk factor predicting a decline in the estimated glomerular filtration rate (eGFR over a 1-year period (hazard ratio: 2.83. In a second approach, we used the NK-CHAT to reveal the cytotoxic potential of circulating alloantibodies in vitro. The level of CD16 engagement resulting from the in vitro recognition of serum-coated allogeneic B cells or splenic cells was further identified as a specific marker of DSA-induced ADCC. The NK-CHAT scoring of sera obtained from 40 patients at the time of transplant biopsy was associated with ABMR diagnosis. Our findings indicate that despite the administration

  6. Antitumor and cytotoxic properties of a humanized antibody specific for the GM3(Neu5Gc) ganglioside.

    Science.gov (United States)

    Dorvignit, Denise; García-Martínez, Liliana; Rossin, Aurélie; Sosa, Katya; Viera, Justo; Hernández, Tays; Mateo, Cristina; Hueber, Anne-Odile; Mesa, Circe; López-Requena, Alejandro

    2015-12-01

    Gangliosides are sialic acid-bearing glycosphingolipids expressed on all mammalian cell membranes, and participate in several cellular processes. During malignant transformation their expression changes, both at the quantitative and qualitative levels. Of particular interest is the overexpression by tumor cells of Neu5Gc-gangliosides, which are absent, or detected in trace amounts, in human normal cells. The GM3(Neu5Gc) ganglioside in particular has been detected in many human tumors, and it is considered one of the few tumor specific antigen. We previously demonstrated that a humanized antibody specific for this molecule, named 14F7hT, retained the binding and cytotoxic properties of the mouse antibody. In this work, we confirm that 14F7hT exerts a non-apoptotic cell death mechanism in vitro and shows its potent in vivo antitumor activity on a solid mouse myeloma model. Also, we demonstrate, in contrast to the murine counterpart, the capacity of this antibody to induce antibody-dependent cell-mediated cytotoxicity using human effector cells, which increases its potential for the treatment of GM3(Neu5Gc)-expressing human tumors. Copyright © 2015 Elsevier GmbH. All rights reserved.

  7. A modified short-term cytotoxicity test

    International Nuclear Information System (INIS)

    Rees, R.C.; Platts, A.A.

    1983-01-01

    Using whole blood from normal subjects, the authors have observed natural killing of K562 cells in a 4 h 51 Cr-release assay comparable with that shown by separated PBMC and whole blood depleted of serum components. Separated plasma was not toxic towards K562 targets, and failed to potentiate the level of PBMC cytotoxicity through ADCC. The presence of red blood cells did not influence natural killing. The natural cytotoxicity of whole blood was augmented by interferon and depressed by prostaglandins E1 and E2. Studies with appropriate control blood fractions show that cytotoxicity tests with whole blood provide results reflecting natural cell-mediated cytotoxicity. (Auth.)

  8. Rebmab200, a Humanized Monoclonal Antibody Targeting the Sodium Phosphate Transporter NaPi2b Displays Strong Immune Mediated Cytotoxicity against Cancer: A Novel Reagent for Targeted Antibody Therapy of Cancer

    Science.gov (United States)

    dos Santos, Mariana Lopes; Yeda, Fernanda Perez; Tsuruta, Lilian Rumi; Horta, Bruno Brasil; Pimenta, Alécio A.; Degaki, Theri Leica; Soares, Ibere C.; Tuma, Maria Carolina; Okamoto, Oswaldo Keith; Alves, Venancio A. F.; Ritter, Gerd; Moro, Ana Maria

    2013-01-01

    NaPi2b, a sodium-dependent phosphate transporter, is highly expressed in ovarian carcinomas and is recognized by the murine monoclonal antibody MX35. The antibody had shown excellent targeting to ovarian cancer in several early phase clinical trials but being murine the antibody's full therapeutic potential could not be explored. To overcome this impediment we developed a humanized antibody version named Rebmab200, expressed in human PER.C6® cells and cloned by limiting dilution. In order to select a clone with high therapeutic potential clones were characterized using a series of physicochemical assays, flow cytometry, real-time surface plasmon resonance, glycosylation analyses, immunohistochemistry, antibody-dependent cell-mediated cytotoxicity, complement-dependent-cytotoxicity assays and quantitative PCR. Comparative analyses of Rebmab200 and MX35 monoclonal antibodies demonstrated that the two antibodies had similar specificity for NaPi2b by flow cytometry with a panel of 30 cell lines and maintained similar kinetic parameters. Robust and high producer cell clones potentially suitable for use in manufacturing were obtained. Rebmab200 antibodies were assessed by immunohistochemistry using a large panel of tissues including human carcinomas of ovarian, lung, kidney and breast origin. An assessment of its binding towards 33 normal human organs was performed as well. Rebmab200 showed selected strong reactivity with the tested tumor types but little or no reactivity with the normal tissues tested confirming its potential for targeted therapeutics strategies. The remarkable cytotoxicity shown by Rebmab200 in OVCAR-3 cells is a significant addition to the traits of stability and productivity displayed by the top clones of Rebmab200. Antibody-dependent cell-mediated toxicity functionality was confirmed in repeated assays using cancer cell lines derived from ovary, kidney and lung as targets. To explore use of this antibody in clinical trials, GMP production of Rebmab

  9. Epidemics with Multistrain Interactions: Cross Immunity and Antibody-Dependent Enhancement

    Science.gov (United States)

    Bianco, Simone; Shaw, Leah

    2008-03-01

    Dynamics of epidemic spread is a problem of global interest. In this work we investigate the dynamical properties of a multistrain disease in a population where the strains interact via antibody-dependent enhancement (ADE) and cross immunity. ADE is a property of some multistrain diseases, such as dengue fever and Ebola, in which the antibodies generated by a primary infection with a strain tend to increase the infectiousness of a secondary infection with a different strain. After a primary infection, cross immunity provides temporary reduced susceptibility to the other strains. The presence of chaotic outbreaks and desynchronization between strains has already been observed in a model with no cross immunity if the ADE is sufficiently strong. The addition of weak cross immunity provides a stabilizing effect, while strong cross immunity leads to large amplitude chaotic outbreaks. A stochastic version of the model is also considered.

  10. Slaying the Trojan horse: natural killer cells exhibit robust anti-HIV-1 antibody-dependent activation and cytolysis against allogeneic T cells.

    Science.gov (United States)

    Gooneratne, Shayarana L; Richard, Jonathan; Lee, Wen Shi; Finzi, Andrés; Kent, Stephen J; Parsons, Matthew S

    2015-01-01

    Many attempts to design prophylactic human immunodeficiency virus type 1 (HIV-1) vaccines have focused on the induction of neutralizing antibodies (Abs) that block infection by free virions. Despite the focus on viral particles, virus-infected cells, which can be found within mucosal secretions, are more infectious than free virus both in vitro and in vivo. Furthermore, assessment of human transmission couples suggests infected seminal lymphocytes might be responsible for a proportion of HIV-1 transmissions. Although vaccines that induce neutralizing Abs are sought, only some broadly neutralizing Abs efficiently block cell-to-cell transmission of HIV-1. As HIV-1 vaccines need to elicit immune responses capable of controlling both free and cell-associated virus, we evaluated the potential of natural killer (NK) cells to respond in an Ab-dependent manner to allogeneic T cells bearing HIV-1 antigens. This study presents data measuring Ab-dependent anti-HIV-1 NK cell responses to primary and transformed allogeneic T-cell targets. We found that NK cells are robustly activated in an anti-HIV-1 Ab-dependent manner against allogeneic targets and that tested target cells are subject to Ab-dependent cytolysis. Furthermore, the educated KIR3DL1(+) NK cell subset from HLA-Bw4(+) individuals exhibits an activation advantage over the KIR3DL1(-) subset that contains both NK cells educated through other receptor/ligand combinations and uneducated NK cells. These results are intriguing and important for understanding the regulation of Ab-dependent NK cell responses and are potentially valuable for designing Ab-dependent therapies and/or vaccines. NK cell-mediated anti-HIV-1 antibody-dependent functions have been associated with protection from infection and disease progression; however, their role in protecting from infection with allogeneic cells infected with HIV-1 is unknown. We found that HIV-1-specific ADCC antibodies bound to allogeneic cells infected with HIV-1 or coated

  11. Antibody-Dependent Enhancement of Dengue Virus Infection in Primary Human Macrophages; Balancing Higher Fusion against Antiviral Responses

    NARCIS (Netherlands)

    Flipse, Jacky; Diosa-Toro, Mayra A.; Hoornweg, Tabitha E.; van de Pol, Denise P. I.; Urcuqui-Inchima, Silvio; Smit, Jolanda M.

    2016-01-01

    The dogma is that the human immune system protects us against pathogens. Yet, several viruses, like dengue virus, antagonize the hosts' antibodies to enhance their viral load and disease severity; a phenomenon called antibody-dependent enhancement of infection. This study offers novel insights in

  12. CD47 limits antibody dependent phagocytosis against non-malignant B cells.

    Science.gov (United States)

    Gallagher, Sandra; Turman, Sean; Lekstrom, Kristen; Wilson, Susan; Herbst, Ronald; Wang, Yue

    2017-05-01

    Recent studies have demonstrated the importance of CD47 in protecting malignant B cells from antibody dependent cellular phagocytosis (ADCP). Combined treatment of anti-CD47 and -CD20 antibodies synergistically augment elimination of tumor B cells in xenograft mouse models. This has led to the development of novel reagents that can potentially enhance killing of malignant B cells in patients. B cell depleting therapy is also a promising treatment for autoimmune patients. In the current study, we aimed to investigate whether or not CD47 protects non-malignant B cells from ADCP. We show that CD47 is expressed on all B cells in mice, with the highest level on plasma cells in bone marrow and spleen. Although its expression is dispensable for B cell development in mice, CD47 on B cells limits antibody mediated phagocytosis. B cell depletion following in vivo anti-CD19 treatment is more efficient in CD47-/- mice than in wild type mice. In vitro, both naïve and activated B cells from CD47-/- mice are more sensitive to ADCP than wild type B cells. Lastly, we show in an ADCP assay that blocking CD47 can enhance anti-CD19 antibody mediated phagocytosis of wild type B cells. These results suggest that in addition to its already demonstrated benefit in cancer, targeting CD47 may be used as an adjunct in combination with B cell depletion antibodies for treatment of autoimmune diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Low Levels of Antibody-Dependent Enhancement in Vitro Using Viruses and Plasma from Dengue Patients

    Science.gov (United States)

    Chaichana, Panjaporn; Okabayashi, Tamaki; Puiprom, Orapim; Sasayama, Mikiko; Sasaki, Tadahiro; Yamashita, Akifumi; Ramasoota, Pongrama; Kurosu, Takeshi; Ikuta, Kazuyoshi

    2014-01-01

    Background The majority of dengue patients infected with any serotype of dengue virus (DENV) are asymptomatic, but the remainder may develop a wide spectrum of clinical symptoms, ranging from mild dengue fever (DF) to severe dengue hemorrhagic fever (DHF). Severe cases occur more often in patients who experience a secondary infection with a different virus serotype. A phenomenon called antibody-dependent enhancement (ADE) has been proposed to explain the onset of these severe cases, but the exact mechanism of ADE remains unclear. Methodology/Principal Finding Virus neutralization and ADE assays were performed using ultracentrifugation supernatants of acute-phase sera from patients with secondary infections or human monoclonal antibodies (HuMAbs) as anti-DENV antibodies. Virus sources included infectious serum-derived viruses from the ultracentrifugation precipitates, laboratory-culture adapted DENV, or recombinant DENVs derived from patient sera. In contrast to the high levels of ADE observed with laboratory virus strains, low ADE was observed with autologous patient-derived viruses, when patient sera were used to provide the antibody component in the ADE assays. Similar results were obtained using samples from DF and DHF patients. Recombinant-viruses derived from DHF patients showed only minor differences in neutralization and ADE activity in the presence of HuMAbs or plasma derived from the same DHF patient. Conclusion/Significance Serum or plasma taken from patients during the acute phase of a secondary infection showed high levels of ADE, but no neutralization activity, when assayed in the presence of laboratory-adapted virus strains. By contrast, serum or plasma from the same patient showed high levels of neutralization activity but failed to induce significant ADE when the assays were performed with autologous virus. These results demonstrate the significance of the virus source when measuring ADE. They also suggest that repeated passage of DENV in cell

  14. Possible neuroimmunomodulation therapy in T-cell-mediated oral diseases

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Sato

    2015-01-01

    Full Text Available Introduction: Recurrent aphthous stomatitis and oral lichen planus are local chronic inflammatory diseases which are implicated in T cell-mediated immunity. According to the systematic review, there is insufficient evidence to support any specific treatment for T-cell mediated oral diseases. The hypothesis: In this paper, we propose a hypothesis that recurrent aphthous stomatitis and oral lichen planus can be treated with selective α7 subunit of nicotinic acetylcholine receptor (α7 -nAChR agonists. Our hypothesis is supported by the following two facts. First, the pathophysiological conditions, T h 1/T h 17 cell activation and autonomic nervous system dysfunction, are observed in T-cell mediated oral diseases as well as in T-cell mediated systemic diseases such as rheumatoid arthritis. Second, the cholinergic anti-inflammatory pathway is inhibited in systemic T-cell mediated chronic inflammatory diseases. On the other hand, treatment with α7 -nAChR agonists which activate the cholinergic anti-inflammatory pathway suppresses neuroinflammation via inhibition of T h 1/T h 17 responses in animal model of systemic T-cell mediated chronic inflammatory diseases. We thus expect that selective α7 -nAChR agonists will be effective for the treatment of T-cell mediated oral diseases. Evaluation of the hypothesis: To test our hypothesis, we need to develop in vivo mouse model of T-cell mediated oral diseases. To evaluate the therapeutic effect of a selective α7 -nAChR agonist, we choose ABT-107 because of its safety and tolerability. We believe that the selective α7 -nAChR agonist, especially ABT-107, may be a therapeutic drug to treat T-cell mediated oral diseases.

  15. Can we find a possible structural explanation for antibody-dependent enhancement of dengue virus infection resulting in hemorrhagic fever?

    Science.gov (United States)

    Mikita, Cecilia P; Padlan, Eduardo A

    2016-03-01

    Dengue virus infection is one of the most prevalent mosquito-borne illnesses worldwide, affecting as many as 400 million persons annually. Most people experience a self-limited viral illness, but some experience life-threatening disease. Subsequent infection with other dengue virus serotypes increases the risk of development of severe dengue disease with plasma leakage with or without hemorrhage and end organ impairment. Antibody-dependent enhancement of dengue virus infection has been implicated in the development of severe dengue disease, previously referred to as dengue hemorrhagic fever and dengue shock syndrome. We propose a structural explanation for the role of non-neutralizing antibodies in the development of antibody-dependent enhancement of dengue virus infection via complement fixation or binding to Fcγ receptors facilitating entry into target cells. Published by Elsevier Ltd.

  16. Antibody-dependent infection of human macrophages by severe acute respiratory syndrome coronavirus.

    Science.gov (United States)

    Yip, Ming Shum; Leung, Nancy Hiu Lan; Cheung, Chung Yan; Li, Ping Hung; Lee, Horace Hok Yeung; Daëron, Marc; Peiris, Joseph Sriyal Malik; Bruzzone, Roberto; Jaume, Martial

    2014-05-06

    Public health risks associated to infection by human coronaviruses remain considerable and vaccination is a key option for preventing the resurgence of severe acute respiratory syndrome coronavirus (SARS-CoV). We have previously reported that antibodies elicited by a SARS-CoV vaccine candidate based on recombinant, full-length SARS-CoV Spike-protein trimers, trigger infection of immune cell lines. These observations prompted us to investigate the molecular mechanisms and responses to antibody-mediated infection in human macrophages. We have used primary human immune cells to evaluate their susceptibility to infection by SARS-CoV in the presence of anti-Spike antibodies. Fluorescence microscopy and real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR) were utilized to assess occurrence and consequences of infection. To gain insight into the underlying molecular mechanism, we performed mutational analysis with a series of truncated and chimeric constructs of fragment crystallizable γ receptors (FcγR), which bind antibody-coated pathogens. We show here that anti-Spike immune serum increased infection of human monocyte-derived macrophages by replication-competent SARS-CoV as well as Spike-pseudotyped lentiviral particles (SARS-CoVpp). Macrophages infected with SARS-CoV, however, did not support productive replication of the virus. Purified anti-viral IgGs, but not other soluble factor(s) from heat-inactivated mouse immune serum, were sufficient to enhance infection. Antibody-mediated infection was dependent on signaling-competent members of the human FcγRII family, which were shown to confer susceptibility to otherwise naïve ST486 cells, as binding of immune complexes to cell surface FcγRII was necessary but not sufficient to trigger antibody-dependent enhancement (ADE) of infection. Furthermore, only FcγRII with intact cytoplasmic signaling domains were competent to sustain ADE of SARS-CoVpp infection, thus providing additional

  17. Cell-mediated immune responses in rainbow trout after DNA immunization against the viral hemorrhagic septicemia virus

    DEFF Research Database (Denmark)

    Utke, Katrin; Kock, Holger; Schuetze, Heike

    2008-01-01

    To identify viral proteins that induce cell-mediated cytotoxicity (CMC) against viral hemorrhagic septicemia virus (VHSV)-infected cells, rainbow trout were immunized with DNA vectors encoding the glycoprotein G or the nucleocapsid protein N of VHSV. The G protein was a more potent trigger...... of cytotoxic cells than the N protein. Peripheral blood leukocytes (PBL) isolated from trout immunized against the G protein killed both VHSV-infected MHC class I matched (RTG-2) and VHSV-infected xenogeneic (EPC) target cells, suggesting the involvement of both cytotoxic T lymphocytes (CTL) and NK cells......, respectively. In contrast, PBL from trout that were immunized against the N protein only killed VHSV-infected RTG-2 cells, indicating that this protein only elicits a CTL response. Further, a significant killing capacity of these PBL was only observed during summer months. PBL from fish that were immunized...

  18. Vulnerability of cultured canine lung tumor cells to NK cell-mediated cytolysis

    International Nuclear Information System (INIS)

    Haley, P.J.; Kohr, J.M.; Kelly, G.; Muggenburg, B.A.; Guilmette, B.A.

    1988-01-01

    Five cell lines, designated as canine lung epithelial cell (CLEP), derived from radiation induced canine lung tumors and canine thyroid adeno-carcinoma (CTAC) cells were compared for their susceptibility to NK cell-mediated cytolysis using peripheral blood lymphocytes from normal, healthy Beagle dogs as effector cells. Effector cells and chromium 51 radiolabeled target cells were incubated for 16 h at ratios of 12.5:1, 25:1, 50:1, and 100:1. Increasing cytolysis was observed for all cell lines as the effector-to-target-cell ratios increased from 12.5:1 to 100:1. The percent cytotoxicity was significantly less for all lung tumor cell lines as compared to CTAC at the 100:1 ratio. One lung tumor cell line, CLEP-9, had 85% of the lytic vulnerability of the CTAC cell line and significantly greater susceptibility to NK cell-mediated lysis than all of the other lung tumor cell lines. Susceptibility to NK cell cytolysis did not correlate with in vivo malignant behavior of the original tumor. These data suggest that cultured canine lung tumor cells are susceptible to NK cell cytolytic activity in vitro and that at least one of these cell lines (CLEP-9) is a candidate for substitution of the standard canine NK cell target, CTAC, in NK cell assays. The use of lung tumor cells in NK cell assays may provide greater insight into the control of lung tumors by immune mechanisms. (author)

  19. Combined effect of x irradiation and cell-mediated immune reaction

    International Nuclear Information System (INIS)

    Song, C.W.; Guertin, D.P.

    1978-01-01

    The combined effect of radiation and cell-mediated immune reaction on tumor cells was investigated in vitro. Mastocytoma P815-X2 cells of DBA mice either were irradiated first and subjected to immune lysis by immune splenic lymphocytes of C57Bl mice, or the tumor cells were subjected to immune reaction first and then irradiated. Cell survival was quantitated by colony formation in soft agar medium. It was observed that cellular immune damage to tumor cells did not influence the response of tumor cells to subsequent radiation. Irradiation of tumor cells first, followed by subjection of the cells to cellular immune reaction, slightly enhanced the death of the tumor cells. It appears that this enhanced death might have resulted from a relative increase in the ratio of the number of cytotoxic immune cells to the number of target tumor cells in the incubation mixture as a consequence of the decrease in the number of viable tumor cells by radiation

  20. Effects of Reactive Nitrogen Scavengers on NK-Cell-Mediated Killing of K562 Cells

    Directory of Open Access Journals (Sweden)

    Yili Zeng

    2012-01-01

    Full Text Available This study explored the effects of reactive nitrogen metabolites (RNMS on natural-killer- (NK- cell-mediated killing of K562 cells and the influence of RNM scavengers, such as tiopronin (TIP, glutamylcysteinylglycine (GSH, and histamine dihydrochloride (DHT, on reversing the suppressing effect of RNM. We administered exogenous and endogenous RNM in the NK + K562 culture system and then added RNM scavengers. The concentrations of RNM, TNF-β and IFN-γ, and NK-cell cytotoxicity (NCC and the percentage of living NK cells were then examined. We found that both exogenous and endogenous RNM caused the KIR to decrease (<0.01; however, RNM scavengers such as TIP and GSH rescued this phenomenon dose dependently. In conclusion, our data suggests that RNM scavengers such as TIP and GSH enhance the antineoplasmic activity of NK cells.

  1. Daratumumab depletes CD38+ immune-regulatory cells, promotes T-cell expansion, and skews T-cell repertoire in multiple myeloma

    DEFF Research Database (Denmark)

    Krejcik, Jakub; Casneuf, Tineke; Nijhof, Inger S

    2016-01-01

    Daratumumab targets CD38-expressing myeloma cells through a variety of immune-mediated mechanisms (complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, and antibody-dependent cellular phagocytosis) and direct apoptosis with cross-linking. These mechanisms may also tar...

  2. Antibody-dependent cellular inhibition is associated with reduced risk against febrile malaria in a longitudinal cohort study involving Ghanaian children

    DEFF Research Database (Denmark)

    Tiendrebeogo, Regis W; Adu, Bright; Singh, Susheel K

    2015-01-01

    The antibody-dependent respiratory burst and opsonic phagocytosis assays have been associated with protection against malaria; however, other mechanisms may also be involved. The antibody-dependent cellular inhibition (ADCI) assay is yet to be correlated with protection in longitudinal cohort stu...... of the ADCI assay as a correlate of protection to guide malaria vaccine studies.......The antibody-dependent respiratory burst and opsonic phagocytosis assays have been associated with protection against malaria; however, other mechanisms may also be involved. The antibody-dependent cellular inhibition (ADCI) assay is yet to be correlated with protection in longitudinal cohort...... studies (LCS). We investigated the relationship between ADCI activity of immunoglobulin G before malaria season and risk of malaria in a LCS involving Ghanaian children. High ADCI activity was significantly associated with reduced risk against malaria. Findings here suggest a potential usefulness...

  3. Mesenchymal stem cell-mediated functional tooth regeneration in swine.

    Directory of Open Access Journals (Sweden)

    Wataru Sonoyama

    2006-12-01

    Full Text Available Mesenchymal stem cell-mediated tissue regeneration is a promising approach for regenerative medicine for a wide range of applications. Here we report a new population of stem cells isolated from the root apical papilla of human teeth (SCAP, stem cells from apical papilla. Using a minipig model, we transplanted both human SCAP and periodontal ligament stem cells (PDLSCs to generate a root/periodontal complex capable of supporting a porcelain crown, resulting in normal tooth function. This work integrates a stem cell-mediated tissue regeneration strategy, engineered materials for structure, and current dental crown technologies. This hybridized tissue engineering approach led to recovery of tooth strength and appearance.

  4. Enhanced antibody-dependent cellular phagocytosis by chimeric monoclonal antibodies with tandemly repeated Fc domains.

    Science.gov (United States)

    Nagashima, Hiroaki; Ootsubo, Michiko; Fukazawa, Mizuki; Motoi, Sotaro; Konakahara, Shu; Masuho, Yasuhiko

    2011-04-01

    We previously reported that chimeric monoclonal antibodies (mAbs) with tandemly repeated Fc domains, which were developed by introducing tandem repeats of Fc domains downstream of 2 Fab domains, augmented binding avidities for all Fcγ receptors, resulting in enhanced antibody (Ab)-dependent cellular cytotoxicity. Here we investigated regarding Ab-dependent cellular phagocytosis (ADCP) mediated by these chimeric mAbs, which is considered one of the most important mechanisms that kills tumor cells, using two-color flow cytometric methods. ADCP mediated by T3-Ab, a chimeric mAb with 3 tandemly repeated Fc domains, was 5 times more potent than that by native anti-CD20 M-Ab (M-Ab hereafter). Furthermore, T3-Ab-mediated ADCP was resistant to competitive inhibition by intravenous Ig (IVIG), although M-Ab-mediated ADCP decreased in the presence of IVIG. An Fcγ receptor-blocking study demonstrated that T3-Ab mediated ADCP via both FcγRIA and FcγRIIA, whereas M-Ab mediated ADCP exclusively via FcγRIA. These results suggest that chimeric mAbs with tandemly repeated Fc domains enhance ADCP as well as ADCC, and that Fc multimerization may significantly enhance the efficacy of therapeutic Abs. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  5. The Major Players in Adaptive Immunity-Cell-mediated Immunity

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 6. The Major Players in Adaptive Immunity - Cell-mediated Immunity. Asma Ahmed Banishree Saha Anand Patwardhan Shwetha Shivaprasad Dipankar Nandi. General Article Volume 14 Issue 6 June 2009 pp 610-621 ...

  6. Different NK cell-activating receptors preferentially recruit Rab27a or Munc13-4 to perforin-containing granules for cytotoxicity

    DEFF Research Database (Denmark)

    Wood, Stephanie M; Meeths, Marie; Chiang, Samuel C C

    2009-01-01

    of perforin-containing lytic granules induced by signals for natural and antibody-dependent cellular cytotoxicity. We demonstrate here that these signals fail to induce degranulation in resting NK cells from Rab27a-deficient patients. In resting NK cells from healthy subjects, endogenous Rab27a and Munc13...... functional antigen-1, NKG2D, or 2B4 induced colocalization of Rab27a, but not Munc13-4, with perforin. Conversely, engagement of antibody-dependent cellular cytotoxicity receptor CD16 induced colocalization of Munc13-4, but not Rab27a, with perforin. Furthermore, colocalization of Munc13-4 with perforin...

  7. Narcolepsy-Associated HLA Class I Alleles Implicate Cell-Mediated Cytotoxicity

    NARCIS (Netherlands)

    Tafti, M.; Lammers, G.J.; Dauvilliers, Y.; Overeem, S.; Mayer, G.; Nowak, J.; Pfister, C.; Dubois, V.; Eliaou, J.F.; Eberhard, H.P.; Liblau, R.; Wierzbicka, A.; Geisler, P.; Bassetti, C.L.; Mathis, J.; Lecendreux, M.; Khatami, R.; Heinzer, R.; Haba-Rubio, J.; Feketeova, E.; Baumann, C.R.; Kutalik, Z.; Tiercy, J.M.

    2016-01-01

    STUDY OBJECTIVES: Narcolepsy with cataplexy is tightly associated with the HLA class II allele DQB1*06:02. Evidence indicates a complex contribution of HLA class II genes to narcolepsy susceptibility with a recent independent association with HLA-DPB1. The cause of narcolepsy is supposed be an

  8. Role of the endothelin axis in astrocyte- and endothelial cell-mediated chemoprotection of cancer cells

    Science.gov (United States)

    Kim, Seung Wook; Choi, Hyun Jin; Lee, Ho-Jeong; He, Junqin; Wu, Qiuyu; Langley, Robert R.; Fidler, Isaiah J.; Kim, Sun-Jin

    2014-01-01

    Background Recent evidence suggests that astrocytes protect cancer cells from chemotherapy by stimulating upregulation of anti-apoptotic genes in those cells. We investigated the possibility that activation of the endothelin axis orchestrates survival gene expression and chemoprotection in MDA-MB-231 breast cancer cells and H226 lung cancer cells. Methods Cancer cells, murine astrocytes, and murine fibroblasts were grown in isolation, and expression of endothelin (ET) peptides and ET receptors (ETAR and ETBR) compared with expression on cancer cells and astrocytes (or cancer cells and fibroblasts) that were co-incubated for 48 hours. Type-specific endothelin receptor antagonists were used to evaluate the contribution of ETAR and ETBR to astrocyte-induced activation of the protein kinase B (AKT)/mitogen-activated protein kinase (MAPK) signal transduction pathways, anti-apoptotic gene expression, and chemoprotection of cancer cells. We also investigated the chemoprotective potential of brain endothelial cells and microglial cells. Results Gap junction signaling between MDA-MB-231 cancer cells and astrocytes stimulates upregulation of interleukin 6 (IL-6) and IL-8 expression in cancer cells, which increases ET-1 production from astrocytes and ET receptor expression on cancer cells. ET-1 signals for activation of AKT/MAPK and upregulation of survival proteins that protect cancer cells from taxol. Brain endothelial cell-mediated chemoprotection of cancer cells also involves endothelin signaling. Dual antagonism of ETAR and ETBR is required to abolish astrocyte- and endothelial cell-mediated chemoprotection. Conclusions Bidirectional signaling between astrocytes and cancer cells involves upregulation and activation of the endothelin axis, which protects cancer cells from cytotoxicity induced by chemotherapeutic drugs. PMID:25008093

  9. [In vitro study of the cytotoxic activity of sipunculid leukocytes towards allogeneic and xenogenic erythrocytes].

    Science.gov (United States)

    Boiledieu, D; Valembois, P

    1976-07-19

    A cell mediated cytotoxic reaction analogous to that known in Vertebrates is induced in vitro by leukocytes of sipunculid worms (coelomata invertebrates). Xenogenic or allogenic erythrocytes are employed as target cells. A cytotoxic effect always occurs when killer leukocytes react against xenogenic cells. A cytotoxic activity against allogenic erythrocytes occurs in all cases when donors of leukocytes and donors of erythrocytes arise from stations far apart (Roscoff and Arcachon). Between stations near each other (4 miles apart) a cytotoxic effect is noticed only in one case out of three. No reaction is noticed between Sipunculus nudus from the same station.

  10. Neonatal Fc Receptor Expression in Dendritic Cells Mediates Protective Immunity Against Colorectal Cancer

    Science.gov (United States)

    Baker, Kristi; Rath, Timo; Flak, Magdalena B.; Arthur, Janelle C.; Chen, Zhangguo; Glickman, Jonathan N.; Zlobec, Inti; Karamitopoulou, Eva; Stachler, Matthew D.; Odze, Robert D.; Lencer, Wayne I.; Jobin, Christian; Blumberg, Richard S.

    2014-01-01

    SUMMARY Cancers arising in mucosal tissues account for a disproportionately large fraction of malignancies. IgG and the neonatal Fc receptor for IgG (FcRn) have an important function in the mucosal immune system which we have now shown extends to the induction of CD8+ T cell-mediated anti-tumor immunity. We demonstrate that FcRn within dendritic cells (DC) was critical for homeostatic activation of mucosal CD8+ T cells which drove protection against the development of colorectal cancers and lung metastases. FcRn-mediated tumor protection was driven by DC activation of endogenous tumor-reactive CD8+ T cells via the cross-presentation of IgG complexed antigens (IgG IC) as well as the induction of cytotoxicity-promoting cytokine secretion, particularly interleukin-12 (IL-12), both of which were independently triggered by the FcRn–IgG IC interaction in murine and human DC. FcRn thus has a primary role within mucosal tissues in activating local immune responses that are critical for priming efficient anti-tumor immunosurveillance. PMID:24290911

  11. The 3 major types of innate and adaptive cell-mediated effector immunity.

    Science.gov (United States)

    Annunziato, Francesco; Romagnani, Chiara; Romagnani, Sergio

    2015-03-01

    The immune system has tailored its effector functions to optimally respond to distinct species of microbes. Based on emerging knowledge on the different effector T-cell and innate lymphoid cell (ILC) lineages, it is clear that the innate and adaptive immune systems converge into 3 major kinds of cell-mediated effector immunity, which we propose to categorize as type 1, type 2, and type 3. Type 1 immunity consists of T-bet(+) IFN-γ-producing group 1 ILCs (ILC1 and natural killer cells), CD8(+) cytotoxic T cells (TC1), and CD4(+) TH1 cells, which protect against intracellular microbes through activation of mononuclear phagocytes. Type 2 immunity consists of GATA-3(+) ILC2s, TC2 cells, and TH2 cells producing IL-4, IL-5, and IL-13, which induce mast cell, basophil, and eosinophil activation, as well as IgE antibody production, thus protecting against helminthes and venoms. Type 3 immunity is mediated by retinoic acid-related orphan receptor γt(+) ILC3s, TC17 cells, and TH17 cells producing IL-17, IL-22, or both, which activate mononuclear phagocytes but also recruit neutrophils and induce epithelial antimicrobial responses, thus protecting against extracellular bacteria and fungi. On the other hand, type 1 and 3 immunity mediate autoimmune diseases, whereas type 2 responses can cause allergic diseases. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  12. Cell-mediated immune responses in the head-associated lymphoid tissues induced to a live attenuated avian coronavirus vaccine.

    Science.gov (United States)

    Gurjar, Rucha S; Gulley, Stephen L; van Ginkel, Frederik W

    2013-12-01

    Humoral immunity is important for controlling viral diseases of poultry, but recent studies have indicated that cytotoxic T cells also play an important role in the immune response to infectious bronchitis virus (IBV). To better understand the cell mediated immune responses to IBV in the mucosal and systemic immune compartments chickens were ocularly vaccinated with IBV. This induced a lymphocyte expansion in head-associated lymphoid tissues (HALT) and to a lesser extent in the spleen, followed by a rapid decline, probably due to homing of lymphocytes out of these organs and contraction of the lymphocyte population. This interpretation was supported by observations that changes in mononuclear cells were mirrored by that in CD3(+)CD44(+) T cell abundance, which presumably represent T effector cells. Increased interferon gamma (IFN-γ) expression was observed in the mucosal immune compartment, i.e., HALT, after primary vaccination, but shifted to the systemic immune compartment after boosting. In contrast, the expression of cytotoxicity-associated genes, i.e., granzyme A (GZMA) and perforin mRNA, remained associated with the HALT after boosting. Thus, an Ark-type IBV ocular vaccine induces a central memory IFN-γ response in the spleen while the cytotoxic effector memory response, as measured by GZMA and perforin mRNA expression, remains associated with CALT after boosting. Copyright © 2013. Published by Elsevier Ltd.

  13. Engineering PTEN-L for Cell-Mediated Delivery.

    Science.gov (United States)

    Lavictoire, Sylvie J; Gont, Alexander; Julian, Lisa M; Stanford, William L; Vlasschaert, Caitlyn; Gray, Douglas A; Jomaa, Danny; Lorimer, Ian A J

    2018-06-15

    The tumor suppressor PTEN is frequently inactivated in glioblastoma. PTEN-L is a long form of PTEN produced by translation from an alternate upstream start codon. Unlike PTEN, PTEN-L has a signal sequence and a tract of six arginine residues that allow PTEN-L to be secreted from cells and be taken up by neighboring cells. This suggests that PTEN-L could be used as a therapeutic to restore PTEN activity. However, effective delivery of therapeutic proteins to treat CNS cancers such as glioblastoma is challenging. One method under evaluation is cell-mediated therapy, where cells with tumor-homing abilities such as neural stem cells are genetically modified to express a therapeutic protein. Here, we have developed a version of PTEN-L that is engineered for enhanced cell-mediated delivery. This was accomplished by replacement of the native leader sequence of PTEN-L with a leader sequence from human light-chain immunoglobulin G (IgG). This version of PTEN-L showed increased secretion and an increased ability to transfer to neighboring cells. Neural stem cells derived from human fibroblasts could be modified to express this version of PTEN-L and were able to deliver catalytically active light-chain leader PTEN-L (lclPTEN-L) to neighboring glioblastoma cells.

  14. Specific cytotoxic T cells are found in the nonrejected kidneys of blood-transfused rats

    International Nuclear Information System (INIS)

    Dallman, M.J.; Wood, K.J.; Morris, P.J.

    1987-01-01

    Preoperative, donor-specific blood transfusion leads to indefinite survival of rat renal allografts in the strain combinations used. 51 Cr-release assays have shown that the level of specific cytotoxic effector activity in the grafts of transfused (nonrejected kidney) animals is very high and may equal or exceed that seen in the grafts of untreated (rejected kidney) recipients. Such cytotoxicity demonstrates specificity for the alloantigens of the kidney, is T cell-mediated, and may persist within the transplant

  15. Streptococcus pneumoniae cocultured with fibroblasts enhances both interferon production and cytotoxic activity by lymphocytes.

    OpenAIRE

    Weigent, D A; Baron, S; Stanton, G J

    1985-01-01

    Cell-mediated cytotoxicity against normal human fibroblasts was dependent on treatment of the fibroblasts with Streptococcus pneumoniae. Both spontaneous and interferon (IFN)-enhanced lymphocytes killed human foreskin (HFS) or skin muscle cells cocultured with S. pneumoniae five- to eightfold more than control nontreated cells. Based on Percoll gradient centrifugation, the cytotoxic effector cell migrated like a large granular lymphocyte. The human IFN produced from mixtures of HFS cells, lym...

  16. The generation of cytotoxic T cell epitopes and their generation for cancer immunotherapy

    NARCIS (Netherlands)

    Kessler, Jan

    2009-01-01

    Cytotoxic T cell epitopes are the targets for a T cell mediated immunotherapy of cancer. The thesis reports on their identification in the tumor associated proteins BCR-ABL and PRAME by the reverse immunology (prediction) strategy. An extended strategy is used, including the analysis of the

  17. Local cell-mediated immune reactions in cancer patients

    International Nuclear Information System (INIS)

    Bilynskij, B.T.; Vasil'ev, N.V.; Volod'ko, N.A.; Akademiya Meditsinskikh Nauk SSSR, Tomsk. Onkologicheskij Nauchnyj Tsentr)

    1988-01-01

    The analysis of 178 cases of stage I-II breast cancer showed morphological features of local cell-mediated immune reactions to be of limited prognostic value. A comparative evaluation of some characteristics of cell surface receptors, such as ability to spontaneous rosette formation with sheep erythrocytes and sensitivty to theophylline, was carried out in lymphocyte samples obtained from tumor tissue and peripheral blood of 76 cancer patients subjected to preoperative radiotherapy. The said parameters were studied in breast cancer patients of rosette-forming cell reaction to theophylline were identified, the incidence of some of them being determined by the presence or absence of regional metastases. The level and functional activity of surface receptors of tumor mononuclear cells proved to influence prognosis

  18. Disturbances of cell-mediated immunity in ornithosis.

    Science.gov (United States)

    Konopka, L; Koba, S; Partyka, M; Maślanka, K; Kryczka, W; Szerszén, B; Bartosz, B

    1984-01-01

    27 cases of ornithosis were observed during an epidemia in 1980 in Kielce and subsequently followed with respect to immunological characteristics of peripheral blood lymphocytes. Blastic transformation of these cells was tested after stimulation in vitro with three different mitogens. Identification of peripheral blood T and B lymphocytes was done using rosette tests (E,EA,EAC) and the occurrence of surface immunoglobulins was determined by the immunofluorescent method with polyvalent anti-immunoglobulin serum. The counts of T and B lymphocytes in the peripheral blood were normal throughout the whole period of the observation, but from the 3rd week on a significant impairment of 3H-thymidine incorporation into the cells stimulated with Con A was observed, and from the 10th week on, this impairment appeared also in cells stimulated with PHA and PWM. These observations revealed considerable disturbances in cell-mediated reactivity in patients with ornithosis and seem to be connected with chronic infection with Chlamydia psittaci.

  19. Cell mediated immune response in human antirabies revaccination

    Directory of Open Access Journals (Sweden)

    Débora Regina Veiga

    1987-04-01

    Full Text Available The occurrence of secondary cell mediated immune response (CMI in human antirabies immunization was studied. The Puenzalida & Palácios vaccine was used because it is routinely used in Brazil. CMI was evaluated by lymphoblastic transformation indices obtained in whole blood culture in the presence of rabies and control (nervous tissue antigens. Eleven volunteers submitted to revaccination constituted the group under study, while three other volunteers submitted primo vaccination were utilized as control group. A clear secondary CMI to rabies antigen was detected in all the revaccinated volunteers who showed earlier and more intense response than the control group. Response to the control antigen, however, present in all the components of the first group was not detectable in two out of the three primovaccinated and very low in the third one.

  20. Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection.

    Science.gov (United States)

    Wang, Miao; Yang, Fan; Huang, Dana; Huang, Yalan; Zhang, Xiaomin; Wang, Chao; Zhang, Shaohua; Zhang, Renli

    2017-01-01

    Dengue virus (DENV) co-circulates as four serotypes (DENV1-4). Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR), a process known as antibody dependent enhancement (ADE). Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM) of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2) and DENV-2 prM monoclonal antibody (prM mAb) could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs) specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo , interferon-α and γ receptor-deficient mice (AG6) were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10) and alaninea minotransferase (ALT) in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo , suggested that anti-idiotypic antibodies might be a new choice to be considered to treat

  1. Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Miao Wang

    2017-05-01

    Full Text Available Dengue virus (DENV co-circulates as four serotypes (DENV1-4. Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS. Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR, a process known as antibody dependent enhancement (ADE. Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2 and DENV-2 prM monoclonal antibody (prM mAb could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo, interferon-α and γ receptor-deficient mice (AG6 were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10 and alaninea minotransferase (ALT in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo, suggested that anti-idiotypic antibodies might be a new choice to be considered to

  2. Mast cell mediator tryptase levels after inhalation or intravenous administration of high doses pharmaceutically prepared heroin

    NARCIS (Netherlands)

    Rook, E. J.; van Zanten, A. P.; van den Brink, W.; van Ree, J. M.; Beijnen, J. H.

    2006-01-01

    BACKGROUND: Opioids like morphine and heroin induce mast cell degranulation in vitro. The release of mast cell mediators like histamine and tryptase may lead to allergic symptoms. In this study it was investigated whether mast cell mediator release also occurs in vivo in addicted patients who

  3. C1-esterase inhibitor blocks T lymphocyte proliferation and cytotoxic T lymphocyte generation in vitro

    DEFF Research Database (Denmark)

    Nissen, Mogens Holst; Bregenholt, S; Nording, J A

    1998-01-01

    cultures grown in the presence of complement-inactivated serum. Read-outs were cell proliferation, lymphokine production and development of T cell-mediated cytotoxicity. We found that addition of C1-inh to MLC and mitogen-exposed murine and human lymphocyte cultures inhibited proliferation, the development...... beta2m in nanomolar amounts to a one-way allogenic mixed lymphocyte culture (MLC) increased the endogenous production of IL-2 and the generation of allo-specific cytotoxic T lymphocytes. C1-inh was purified from fresh human plasma and added to human or murine MLC and mitogen-stimulated lymphocyte...... of allospecific cytotoxic activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12 and IFN-gamma. These data clearly demonstrate a regulatory function of C1-inh on T cell-mediated immune functions....

  4. Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches.

    Science.gov (United States)

    Akram, Khondoker M; Patel, Neil; Spiteri, Monica A; Forsyth, Nicholas R

    2016-01-19

    The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or insult, a specialised group of facultative lung progenitors become activated to replenish damaged tissue through a reparative process called regeneration. Disruption in this process results in healing by fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent studies provide exciting and novel insights into postnatal lung development and post-injury lung regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem cells, embryonic stem cells and inducible pluripotent stem cells (iPSC) show evidences of their regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold and stem cells is now becoming reality. In this review, we will highlight the advancement of our understanding in lung regeneration and development of stem cell mediated therapeutic strategies in combating incurable lung diseases.

  5. Cell-mediated immunity during syphilis. A review

    Science.gov (United States)

    Pavia, Charles S.; Folds, James D.; Baseman, Joel B.

    1978-01-01

    Evidence is presented which reinforces the complexity of the host-parasite interaction during the course of syphilis. Infection with Treponema pallidum evokes a complicated antibody response and an assortment of cell-mediated immune reactions in the host. It appears that humoral immunity plays a minor role towards the complete elimination of syphilitic infection while the cellular limb of the immune response may be an important host defence mechanism. Information now available indicates that a state of anergy, or immunosuppression, exists in the early stages of human and experimental rabbit syphilis based upon negative skin reactions to T. pallidum antigen(s), the abnormal histological appearance of lymphoid organs, and impaired in vitro lymphocyte reactivity. It is also evident that in the later stages of the disease cellular immunity becomes activated as delayed type skin reactions can normally be elicited in tertiary syphilitics and lymphocyte behaviour in cell culture appears normal. Several mechanisms have been invoked to explain the delay in an effective immune response against syphilitic infection and the duration of the disease: (1) a capsule-like substance on the outer surface of virulant T. pallidum may act as a barrier against treponemicidal antibody; (2) this material and other biological properties of virulent treponemes could enable spirochaetes to escape being engulfed by macrophages and other phagocytic cells; (3) antigenic competition among different treponemal antigens causing partial tolerance; (4) T. pallidum infection may bring about the elaboration of immunosuppressive substances of host or treponemal origin which inhibit the proper function of lymphocytes, macrophages, and other cell types. PMID:350348

  6. Cell-mediated non-allergic rhinitis in children.

    Science.gov (United States)

    Maselli Del Giudice, Alessandro; Barbara, Michele; Russo, Giuseppe Maria; Fiocca Matthews, Emily; Cassano, Michele

    2012-12-01

    Non-allergic rhinitis is a heterogeneous disease whose etiology is largely unknown. Nasal cytology only allows us to recognize different non-allergic rhinitis forms on the basis of the prevalent inflammatory cell infiltrate: non-allergic rhinitis with eosinophils, with neutrophils, with mast-cells and with both eosinophils and mast-cells. The aim of this study is to define the incidence, clinical features and comorbidity of the different types of cell-mediated non-allergic rhinitis in a pediatric age group. One hundred and fourteen non-allergic children with chronic nasal obstruction and associated symptoms (rhinorrhea, sneezing and nasal itchiness) were retrospectively selected. All patients had been submitted to a clinical history, pediatric evaluation, anterior rhinoscopy and fiberendoscopy, rhinomanometry and nasal cytology. Non-allergic rhinitis with neutrophils was present in 46 (40.4%) children, non-allergic rhinitis with eosinophils in 53 (46.5%), non-allergic rhinitis with mast-cells in 12 (10.5%) and non-allergic rhinitis with both eosinophils and mast-cells in 3 (2.6%). Nasal obstruction was prevalent in non-allergic rhinitis with eosinophils and in non-allergic rhinitis with mast-cells patients (Pallergic rhinitis with eosinophils group showed a higher probability of asthma (Ppediatric age group the most frequent forms of non-allergic rhinitis are those with eosinophils or with neutrophils. A diagnosis of non-allergic rhinitis with eosinophils in children presumes more severe symptoms and a higher incidence of pulmonary disease and roncopathy. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. B-cell-mediated strategies to fight chronic allograft rejection

    Directory of Open Access Journals (Sweden)

    Ali H Dalloul

    2013-12-01

    Full Text Available Solid organs have been transplanted for decades. Since the improvement in graft selection and in medical and surgical procedures, the likelihood of graft function after one year is now close to 90%. Nonetheless even well-matched recipients continue to need medications for the rest of their lives hence adverse side effects and enhanced morbidity. Understanding Immune rejection mechanisms, is of increasing importance since the greater use of living-unrelated donors and genetically unmatched individuals. Chronic rejection is devoted to T-cells, however the role of B-cells in rejection has been appreciated recently by the observation that B-cell depletion improve graft survival. By contrast however, B-cells can be beneficial to the grafted tissue. This protective effect is secondary to either the secretion of protective antibodies or the induction of B-cells that restrain excessive inflammatory responses, chiefly by local provision of IL-10, or inhibit effector T-cells by direct cellular interactions. As a proof of concept B-cell-mediated infectious transplantation tolerance could be achieved in animal models, and evidence emerged that the presence of such B-cells in transplanted patients correlate with a favorable outcome. Among these populations, regulatory B-cells constitute a recently described population. These cells may develop as a feedback mechanism to prevent uncontrolled reactivity to antigens and inflammatory stimuli. The difficult task for the clinician, is to quantify the respective ratios and functions of tolerant vs effector B-cells within a transplanted organ, at a given time point in order to modulate B-cell-directed therapy. Several receptors at the B-cell membrane as well as signaling molecules, can now be targeted for this purpose. Understanding the temporal expansion of regulatory B-cells in grafted patients and the stimuli that activate them will help in the future to implement specific strategies aimed at fighting chronic

  8. Differences in Granule Morphology yet Equally Impaired Exocytosis among Cytotoxic T Cells and NK Cells from Chediak-Higashi Syndrome Patients.

    Science.gov (United States)

    Chiang, Samuel C C; Wood, Stephanie M; Tesi, Bianca; Akar, Himmet Haluk; Al-Herz, Waleed; Ammann, Sandra; Belen, Fatma Burcu; Caliskan, Umran; Kaya, Zühre; Lehmberg, Kai; Patiroglu, Turkan; Tokgoz, Huseyin; Ünüvar, Ayşegül; Introne, Wendy J; Henter, Jan-Inge; Nordenskjöld, Magnus; Ljunggren, Hans-Gustaf; Meeths, Marie; Ehl, Stephan; Krzewski, Konrad; Bryceson, Yenan T

    2017-01-01

    Chediak-Higashi syndrome (CHS) is caused by autosomal recessive mutations in LYST , resulting in enlarged lysosomal compartments in multiple cell types. CHS patients display oculocutaneous albinism and may develop life-threatening hemophagocytic lymphohistiocytosis (HLH). While NK cell-mediated cytotoxicity has been reported to be uniformly defective, variable defects in T cell-mediated cytotoxicity has been observed. The latter has been linked to the degree of HLH susceptibility. Since the discrepancies in NK cell- and T cell-mediated cellular cytotoxicity might result from differences in regulation of cytotoxic granule release, we here evaluated perforin-containing secretory lysosome size and number in freshly isolated lymphocytes from CHS patients and furthermore compared their exocytic capacities. Whereas NK cells from CHS patients generally contained a single, gigantic perforin-containing granule, cytotoxic T cells predominantly contained several smaller granules. Nonetheless, in a cohort of 21 CHS patients, cytotoxic T cell and NK cell granule exocytosis were similarly impaired upon activating receptor stimulation. Mechanistically, polarization of cytotoxic granules was defective in cytotoxic lymphocytes from CHS patients, with EEA1, a marker of early endosomes, mislocalizing to lysosomal structures. The results leads to the conclusion that lysosome enlargement corresponds to loss of distinct organelle identity in the endocytic pathway, which on a subcellular level more adversely affects NK cells than T cells. Hence, vesicular size or numbers do not per se dictate the impairment of lysosomal exocytosis in the two cell types studied.

  9. Differences in Granule Morphology yet Equally Impaired Exocytosis among Cytotoxic T Cells and NK Cells from Chediak–Higashi Syndrome Patients

    Science.gov (United States)

    Chiang, Samuel C. C.; Wood, Stephanie M.; Tesi, Bianca; Akar, Himmet Haluk; Al-Herz, Waleed; Ammann, Sandra; Belen, Fatma Burcu; Caliskan, Umran; Kaya, Zühre; Lehmberg, Kai; Patiroglu, Turkan; Tokgoz, Huseyin; Ünüvar, Ayşegül; Introne, Wendy J.; Henter, Jan-Inge; Nordenskjöld, Magnus; Ljunggren, Hans-Gustaf; Meeths, Marie; Ehl, Stephan; Krzewski, Konrad; Bryceson, Yenan T.

    2017-01-01

    Chediak–Higashi syndrome (CHS) is caused by autosomal recessive mutations in LYST, resulting in enlarged lysosomal compartments in multiple cell types. CHS patients display oculocutaneous albinism and may develop life-threatening hemophagocytic lymphohistiocytosis (HLH). While NK cell-mediated cytotoxicity has been reported to be uniformly defective, variable defects in T cell-mediated cytotoxicity has been observed. The latter has been linked to the degree of HLH susceptibility. Since the discrepancies in NK cell- and T cell-mediated cellular cytotoxicity might result from differences in regulation of cytotoxic granule release, we here evaluated perforin-containing secretory lysosome size and number in freshly isolated lymphocytes from CHS patients and furthermore compared their exocytic capacities. Whereas NK cells from CHS patients generally contained a single, gigantic perforin-containing granule, cytotoxic T cells predominantly contained several smaller granules. Nonetheless, in a cohort of 21 CHS patients, cytotoxic T cell and NK cell granule exocytosis were similarly impaired upon activating receptor stimulation. Mechanistically, polarization of cytotoxic granules was defective in cytotoxic lymphocytes from CHS patients, with EEA1, a marker of early endosomes, mislocalizing to lysosomal structures. The results leads to the conclusion that lysosome enlargement corresponds to loss of distinct organelle identity in the endocytic pathway, which on a subcellular level more adversely affects NK cells than T cells. Hence, vesicular size or numbers do not per se dictate the impairment of lysosomal exocytosis in the two cell types studied. PMID:28458669

  10. Micronutrient supplementation and T-cell mediated immune responses in patients with tuberculosis in Tanzania

    Science.gov (United States)

    Limited studies exist regarding whether incorporating micronutrient supplements during tuberculosis (TB) treatment may improve cell-mediated immune response. We examine the effect of micronutrient supplementation on lymphocyte proliferation response to mycobacteria or T cell mitogens in a randomize...

  11. Role of macrophage inflammatory protein-1alpha in T-cell-mediated immunity to viral infection

    DEFF Research Database (Denmark)

    Madsen, Andreas N; Nansen, Anneline; Christensen, Jan P

    2003-01-01

    The immune response to lymphocytic choriomeningitis virus in mice lacking macrophage inflammatory protein-1alpha (MIP-1alpha) was evaluated. Generation of virus-specific effector T cells is unimpaired in MIP-1alpha-deficient mice. Furthermore, MIP-1alpha is not required for T-cell-mediated virus...... control or virus-induced T-cell-dependent inflammation. Thus, MIP-1alpha is not mandatory for T-cell-mediated antiviral immunity....

  12. Glycan elongation beyond the mucin associated Tn antigen protects tumor cells from immune-mediated killing

    DEFF Research Database (Denmark)

    Madsen, Caroline B; Lavrsen, Kirstine; Steentoft, Catharina

    2013-01-01

    and pancreatic cancer cell lines T47D and Capan-1 increases sensitivity to both NK cell mediated antibody-dependent cellular-cytotoxicity (ADCC) and cytotoxic T lymphocyte (CTL)-mediated killing. In addition, we investigated the association between total cell surface expression of MUC1/MUC16 and NK or CTL...

  13. Follicular lymphoma: in vitro effects of combining lymphokine-activated killer (LAK) cell-induced cytotoxicity and rituximab- and obinutuzumab-dependent cellular cytotoxicity (ADCC) activity.

    Science.gov (United States)

    García-Muñoz, Ricardo; López-Díaz-de-Cerio, Ascensión; Feliu, Jesus; Panizo, Angel; Giraldo, Pilar; Rodríguez-Calvillo, Mercedes; Grande, Carlos; Pena, Esther; Olave, Mayte; Panizo, Carlos; Inogés, Susana

    2016-04-01

    Follicular lymphoma (FL) is a disease of paradoxes-incurable but with a long natural history. We hypothesized that a combination of lymphokine-activated killer (LAK) cells and monoclonal antibodies might provide a robust synergistic treatment and tested this hypothesis in a phase II clinical trial (NCT01329354). In this trial, in addition to R-CHOP, we alternated the administration of only rituximab with rituximab and autologous LAK cells that were expanded ex vivo. Our objective was to determine the in vitro capability of LAK cells generated from FL patients to produce cytotoxicity against tumor cell lines and to determine rituximab- and obinutuzumab-induced cytotoxicity via antibody-dependent cellular cytotoxicity (ADCC) activity. We analyzed the LAK cell-induced cytotoxicity and rituximab (R)- and obinutuzumab (GA101)-induced ADCC activity. We show that LAK cells generated from FL patients induce cytotoxicity against tumor cell lines. R and GA101 enhance cytolysis through ADCC activity of LAK cells. Impaired LAK cell cytotoxicity and ADCC activity were detected in 50 % of patients. Percentage of NK cells in LAK infusions were correlated with the R- and GA101-induced ADCC. Our results indicate that the combination of R or GA101 and LAK cells should be an option as frontline maintenance therapy in patients with FL.

  14. The Effect of radiation on T-cell mitosis and natural killer cell mediated cytotoxicity in solid cancer patients

    International Nuclear Information System (INIS)

    Choi, Il Bong; Bahk, Yong Whee

    1986-01-01

    The present study has been conducted to investigate whether such tests can be used as a guideline in planning radiation therapy and in prognosticating radiation treatment of patients with a solid cancer. The first group consisted of 68 patients with solid tumors who received radiation therapy from May 1984 until July 1985 at the Department of Radiology, Catholic Medical College and these showed the following results of T-cell function change by the phytohemagglutinin (PHA) stimulation test and the response of the NK cell in vivo following radiation by NKMC test. Secondly the NKMC and PHA stimulation tests have been studied in 27 patients with solid tumors who did not receive radiation therapy (cancer control group) and thirdly 30 normal subjects were tested as normal control. (Author)

  15. Relationship between laminin binding capacity and laminin expression on tumor cells sensitive or resistant to natural cell-mediated cytotoxicity

    International Nuclear Information System (INIS)

    Laybourn, K.A.; Varani, J.; Fligiel, S.E.G.; Hiserodt, J.C.

    1986-01-01

    Previous studies have identified the presence of laminin binding sites on murine NK and NC sensitive tumor cells by 125 I-laminin binding and laminin induced cell-cell aggregation. The finding that the addition of exogenous laminin inhibits NK/NC binding to sensitive tumor cells suggests laminin binding sites may serve as target antigens for NK cells. The present study extends earlier reports by analyzing a large panel of tumor cells for laminin binding capacity, laminin expression and sensitivity to NK/NC killing. The data indicate that all tumor cells which bind to NK/NC cells (8 lines tested) express laminin binding sites. All of these tumor cells were capable of competing for NK lysis of YAC-1 cells in cold target competition assays, and all bound enriched NK cells in direct single cell binding assays. In contrast, tumor cells expressing high levels of surface laminin (B16 melanomas, C57B1/6 fibrosarcomas, and RAS transfected 3T3 fibroblasts) but low levels of laminin binding capacity did not bind NK/NC cells and were resistant to lysis. These data support the hypothesis that expression of laminin/laminin binding sites may contribute to tumor cell sensitivity to NK/NC binding and/or killing

  16. Induction of human immunodeficiency virus (HIV-1 envelope specific cell-mediated immunity by a non-homologous synthetic peptide.

    Directory of Open Access Journals (Sweden)

    Ammar Achour

    2007-11-01

    Full Text Available Cell mediated immunity, including efficient CTL response, is required to prevent HIV-1 from cell-to-cell transmission. In previous investigations, we have shown that B1 peptide derived by Fourier transformation of HIV-1 primary structures and sharing no sequence homology with the parent proteins was able to generate antiserum which recognizes envelope and Tat proteins. Here we have investigated cellular immune response towards a novel non-homologous peptide, referred to as cA1 peptide.The 20 amino acid sequence of cA1 peptide was predicted using the notion of peptide hydropathic properties; the peptide is encoded by the complementary anti-sense DNA strand to the sense strand of previously described non-homologous A1 peptide. In this report we demonstrate that the cA1 peptide can be a target for major histocompatibility complex (MHC class I-restricted cytotoxic T lymphocytes in HIV-1-infected or envelope-immunized individuals. The cA1 peptide is recognized in association with different MHC class I allotypes and could prime in vitro CTLs, derived from gp160-immunized individuals capable to recognize virus variants.For the first time a theoretically designed immunogen involved in broad-based cell-immune memory activation is described. Our findings may thus contribute to the advance in vaccine research by describing a novel strategy to develop a synthetic AIDS vaccine.

  17. Hemolytic disease of the fetus and newborn due to anti-Ge3: combined antibody-dependent hemolysis and erythroid precursor cell growth inhibition.

    Science.gov (United States)

    Blackall, Douglas P; Pesek, Gina D; Montgomery, Matthew M; Oza, Krishna K; Arndt, Patricia A; Garratty, George; Shahcheraghi, Ali; Denomme, Gregory A

    2008-10-01

    The Gerbich (Ge) antigens are a collection of high-incidence antigens carried on the red blood cell membrane glycoproteins, glycophorins C and D. Antibodies against these antigens are uncommon, and there have been only rare case reports of hemolytic disease of the fetus and newborn due to anti-Ge. In this case report, we present a neonate with severe anemia and hyperbilirubinemia due to anti-Ge3. Routine and special laboratory studies undertaken in this case suggested two mechanisms for the patient's hemolysis and persistent anemia. Antibody-dependent hemolysis was associated with early-onset hyperbilirubinemia, anemia, and a mild reticulocytosis, and inhibition of erythroid progenitor cell growth was associated with late anemia and normal bilirubin and reticulocyte values. Though rare, anti-Ge3 can be a dangerous antibody in pregnancy. Affected neonates may require intensive initial therapy and close follow-up for at least several weeks after delivery.

  18. Marrow grafts between phenotypically DLA-identical and haploidentical unrelated dogs: additional antigens controlling engraftment are not detected by cell-mediated lympholysis

    Energy Technology Data Exchange (ETDEWEB)

    Deeg, H.J. (Fred Hutchinson Cancer Research Center, Seattle, WA); Storb, R.; Raff, R.F.; Weiden, P.L.; DeRose, S.; Thomas, E.D.

    1982-01-01

    Bone marrow transplants with low marrow cell doses (less than or equal to4 X 10/sup 8/ cells/kg) from unrelated donors were carried out in 16 dogs conditioned with 9 Gy (900 rad) of total body irradiation. No immunosuppression was given after grafting. Eleven donor-recipient pairs were phenotypically identical (group 1) for the known antigens of the canine major histocompatibility complex (DLA) and in five the donor was homozygous and the recipient heterozygous for DLA (group 2), as determined by serological histocompatibility typing and mixed leukocyte cultures including homozygous cell typing. In addition, lymphocytes from donors and recipients in group 1 were mutually nonreactive in cell-mediated lympholysis; lymphocytes from recipients in group 2 were not cytotoxic against donor cells. Eight dogs rejected their grafts and eight showed sustained engraftment; of these, four died from graft-versus-host disease. The incidence of rejection was higher than in DLA-identical littermates but lower than in DLA-nonidentical unrelated or littermate dogs. These results indicate that antigens different from the recognized alleles at DLA are involved in the control of engraftment. These antigens most likely represent the expression of unrecognized differences within DLA or are coded for by a locus different from but linked to DLA-A, B, C or D; they are not recognized in the cell-mediated lympholysis assay.

  19. Bystander apoptosis in human cells mediated by irradiated blood plasma

    Energy Technology Data Exchange (ETDEWEB)

    Vinnikov, Volodymyr, E-mail: vlad.vinnikov@mail.ru [Grigoriev Institute for Medical Radiology of the National Academy of Medical Science of Ukraine (Ukraine); Lloyd, David; Finnon, Paul [Centre for Radiation, Chemical and Environmental Hazards of the Health Protection Agency of the United Kingdom (United Kingdom)

    2012-03-01

    Following exposure to high doses of ionizing radiation, due to an accident or during radiotherapy, bystander signalling poses a potential hazard to unirradiated cells and tissues. This process can be mediated by factors circulating in blood plasma. Thus, we assessed the ability of plasma taken from in vitro irradiated human blood to produce a direct cytotoxic effect, by inducing apoptosis in primary human peripheral blood mononuclear cells (PBM), which mainly comprised G{sub 0}-stage lymphocytes. Plasma was collected from healthy donors' blood irradiated in vitro to 0-40 Gy acute {gamma}-rays. Reporter PBM were separated from unirradiated blood with Histopaque and held in medium with the test plasma for 24 h at 37 Degree-Sign C. Additionally, plasma from in vitro irradiated and unirradiated blood was tested against PBM collected from blood given 4 Gy. Apoptosis in reporter PBM was measured by the Annexin V test using flow cytometry. Plasma collected from unirradiated and irradiated blood did not produce any apoptotic response above the control level in unirradiated reporter PBM. Surprisingly, plasma from irradiated blood caused a dose-dependent reduction of apoptosis in irradiated reporter PBM. The yields of radiation-induced cell death in irradiated reporter PBM (after subtracting the respective values in unirradiated reporter PBM) were 22.2 {+-} 1.8% in plasma-free cultures, 21.6 {+-} 1.1% in cultures treated with plasma from unirradiated blood, 20.2 {+-} 1.4% in cultures with plasma from blood given 2-4 Gy and 16.7 {+-} 3.2% in cultures with plasma from blood given 6-10 Gy. These results suggested that irradiated blood plasma did not cause a radiation-induced bystander cell-killing effect. Instead, a reduction of apoptosis in irradiated reporter cells cultured with irradiated blood plasma has implications concerning oncogenic risk from mutated cells surviving after high dose in vivo irradiation (e.g. radiotherapy) and requires further study.

  20. Bystander apoptosis in human cells mediated by irradiated blood plasma

    International Nuclear Information System (INIS)

    Vinnikov, Volodymyr; Lloyd, David; Finnon, Paul

    2012-01-01

    Following exposure to high doses of ionizing radiation, due to an accident or during radiotherapy, bystander signalling poses a potential hazard to unirradiated cells and tissues. This process can be mediated by factors circulating in blood plasma. Thus, we assessed the ability of plasma taken from in vitro irradiated human blood to produce a direct cytotoxic effect, by inducing apoptosis in primary human peripheral blood mononuclear cells (PBM), which mainly comprised G 0 -stage lymphocytes. Plasma was collected from healthy donors’ blood irradiated in vitro to 0–40 Gy acute γ-rays. Reporter PBM were separated from unirradiated blood with Histopaque and held in medium with the test plasma for 24 h at 37 °C. Additionally, plasma from in vitro irradiated and unirradiated blood was tested against PBM collected from blood given 4 Gy. Apoptosis in reporter PBM was measured by the Annexin V test using flow cytometry. Plasma collected from unirradiated and irradiated blood did not produce any apoptotic response above the control level in unirradiated reporter PBM. Surprisingly, plasma from irradiated blood caused a dose-dependent reduction of apoptosis in irradiated reporter PBM. The yields of radiation-induced cell death in irradiated reporter PBM (after subtracting the respective values in unirradiated reporter PBM) were 22.2 ± 1.8% in plasma-free cultures, 21.6 ± 1.1% in cultures treated with plasma from unirradiated blood, 20.2 ± 1.4% in cultures with plasma from blood given 2–4 Gy and 16.7 ± 3.2% in cultures with plasma from blood given 6–10 Gy. These results suggested that irradiated blood plasma did not cause a radiation-induced bystander cell-killing effect. Instead, a reduction of apoptosis in irradiated reporter cells cultured with irradiated blood plasma has implications concerning oncogenic risk from mutated cells surviving after high dose in vivo irradiation (e.g. radiotherapy) and requires further study.

  1. TNFα and IFNγ but not perforin are critical for CD8 T cell-mediated protection against pulmonary Yersinia pestis infection.

    Science.gov (United States)

    Szaba, Frank M; Kummer, Lawrence W; Duso, Debra K; Koroleva, Ekaterina P; Tumanov, Alexei V; Cooper, Andrea M; Bliska, James B; Smiley, Stephen T; Lin, Jr-Shiuan

    2014-05-01

    Septic pneumonias resulting from bacterial infections of the lung are a leading cause of human death worldwide. Little is known about the capacity of CD8 T cell-mediated immunity to combat these infections and the types of effector functions that may be most effective. Pneumonic plague is an acutely lethal septic pneumonia caused by the Gram-negative bacterium Yersinia pestis. We recently identified a dominant and protective Y. pestis antigen, YopE69-77, recognized by CD8 T cells in C57BL/6 mice. Here, we use gene-deficient mice, Ab-mediated depletion, cell transfers, and bone marrow chimeric mice to investigate the effector functions of YopE69-77-specific CD8 T cells and their relative contributions during pulmonary Y. pestis infection. We demonstrate that YopE69-77-specific CD8 T cells exhibit perforin-dependent cytotoxicity in vivo; however, perforin is dispensable for YopE69-77-mediated protection. In contrast, YopE69-77-mediated protection is severely impaired when production of TNFα and IFNγ by CD8 T cells is simultaneously ablated. Interestingly, TNFα is absolutely required at the time of challenge infection and can be provided by either T cells or non-T cells, whereas IFNγ provided by T cells prior to challenge appears to facilitate the differentiation of optimally protective CD8 T cells. We conclude that cytokine production, not cytotoxicity, is essential for CD8 T cell-mediated control of pulmonary Y. pestis infection and we suggest that assays detecting Ag-specific TNFα production in addition to antibody titers may be useful correlates of vaccine efficacy against plague and other acutely lethal septic bacterial pneumonias.

  2. IL-10 polymorphism and cell-mediated immune response to Chlamydia trachomatis

    DEFF Research Database (Denmark)

    Öhman, H.; Tiitinen, A; Halttunen, M.

    2006-01-01

    background. To study a relationship between interleukin-10 (IL-10) promoter -1082 polymorphism and cell-mediated immune response during C trachomatis infection in vitro, lymphocyte proliferation and cytokine (IL-10, IFN-gamma, TNF-alpha, IL-2, IL-4 and IL-5) secretion were analysed in subjects with different...... IL-10 genotypes. Enhanced IL-10 secretion and reduced antigen-specific lymphocyte proliferative and IFN-gamma responses were found in subjects with IL-10 -1082 GG genotype when compared to those with -1082 AA genotype. CD14+ monocytes were main source of IL-10 indicating that these cells...... are important regulators of the antigen-specific cell-mediated responses during active C trachomatis infection. We conclude that impaired cell-mediated response to C trachomatis is associated with IL-10 genotype in subjects with high IL-10 producing capacity. A comparison of immune markers between subjects...

  3. Analysis of cell-mediated immune responses in support of dengue vaccine development efforts.

    Science.gov (United States)

    Rothman, Alan L; Currier, Jeffrey R; Friberg, Heather L; Mathew, Anuja

    2015-12-10

    Dengue vaccine development has made significant strides, but a better understanding of how vaccine-induced immune responses correlate with vaccine efficacy can greatly accelerate development, testing, and deployment as well as ameliorate potential risks and safety concerns. Advances in basic immunology knowledge and techniques have already improved our understanding of cell-mediated immunity of natural dengue virus infection and vaccination. We conclude that the evidence base is adequate to argue for inclusion of assessments of cell-mediated immunity as part of clinical trials of dengue vaccines, although further research to identify useful correlates of protective immunity is needed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Tumor Induced Inactivation of Natural Killer Cell Cytotoxic Function; Implication in Growth, Expansion and Differentiation of Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Anahid Jewett, Han-Ching Tseng

    2011-01-01

    Full Text Available Accumulated evidence indicates that cytotoxic function of immune effectors is largely suppressed in the tumor microenvironment by a number of distinct effectors and their secreted factors. The aims of this review are to provide a rationale and a potential mechanism for immunosuppression in cancer and to demonstrate the significance of such immunosuppression in cellular differentiation and progression of cancer. To that end, we have recently shown that NK cells mediate significant cytotoxicity against primary oral squamous carcinoma stem cells (OSCSCs as compared to their more differentiated oral squamous carcinoma cells (OSCCs. In addition, human embryonic stem cells (hESCs, Mesenchymal Stem Cells (hMSCs, dental pulp stem cells (hDPSCs and induced pluripotent stem cells (hiPSCs were all significantly more susceptible to NK cell mediated cytotoxicity than their differentiated counterparts or parental cells from which they were derived. We have also reported that inhibition of differentiation or reversion of cells to a less-differentiated phenotype by blocking NFκB or targeted knock down of COX2 in primary monocytes in vivo significantly augmented NK cell function. Total population of monocytes and those depleted of CD16(+ subsets were able to substantially prevent NK cell mediated lysis of OSCSCs, MSCs and DPSCs. Taken together, our results suggest that stem cells are significant targets of the NK cell cytotoxicity. The concept of split anergy in NK cells and its contribution to tissue repair and regeneration and in tumor resistance and progression will be discussed in this review.

  5. Korean mistletoe lectin enhances natural killer cell cytotoxicity via upregulation of perforin expression.

    Science.gov (United States)

    Kim, Younghoon; Kim, Inbo; Park, Choon-Ho; Kim, Jong Bae

    2018-03-31

    Natural killer (NK) cells are crucial components of the innate immune system, providing the first line of defense against pathogens. In a previous study, we demonstrated prophylactic activity of water extract of Korean mistletoe (Viscum album coloratum) on tumor metastasis. However, the leading compound from water extract of Korean mistletoe was not clearly addressed. The purpose of this research was mainly focused on addressing the effect of Korean mistletoe lectin (KMLC) on NK cell cytotoxicity, and the ability of cytokine secretion as well as its signal transduction, mitogen-activated protein kinase (MAPK) pathway. KMLC was used to test NK cell-mediated cytotoxicity in vitro and in vivo. Non-isotope cytotoxicity assay (bis-N,N,N',N'-tetraacetic acid (BATDA) release assay) was performed to test the cytotoxicity of NK cells against target tumor cells. Receptor expression was checked by flow cytometry analysis and MAPK signal molecules were analyzed by immunoblotting. KMLC at 200 ng/mL increased the cytotoxicity of NK92 cells by 35% compared with untreated cells. KMLC-treated (at 100 ng/mL) mice splenocytes showed a 20% increase in cytotoxic activity. Also, the B chain, one of the subchains of KMLC, increases perforin expression. We demonstrated that the signal transduction controlling NK cell cytotoxicity was mediated by upregulation of the NKG2D receptor and expression of a cytotoxic effector molecule. These results suggested that KMLC possessed immunological activity, mediated by NK cell activation.

  6. Cell-mediated immunity in Aujeszky disease virus infected pigs. I. Lymphocyte stimulation.

    Science.gov (United States)

    Wittmann, G; Bartenbach, G; Jakubik, J

    1976-01-01

    The appearance of cell-mediated immunity was studied in Aujeszky diseased pigs with the aid of the in vitro stimulation of sensitized lymphocytes. The first cell-mediated immunity reaction of lymphocytes occurred 4 days after infection. From day 7 to 35, the latest day tested, the reactions were most marked with lymphocytes from lymph nodes and spleen, whereas blood and thymus lymphocytes reacted less frequently; bone marrow lymphocytes showed no response. Reinfection did not considerably enhance lymphocyte reactivity. Humoral immunity was demonstrated a few days later than cell-mediated immunity. Neutralizing antibodies were first detected at day 7, reaching optimal titers at day 14. Complement fixing antibodies were detected from day 14 onward. Reinfection caused a very weak booster effect only on neutralizing antibody production. The sensitivity of the neutralization test could be enhanced up to sixfold by the addition of fresh guinea pig complement. It is concluded that cell-mediated immunity influences the early stage of infection with Aujeszky disease virus when humoral immunity is not yet demonstrable or yet rather low. Lymph nodes and spleen are apparently of special importance for the appearance of ADV-reactive lymphocytes.

  7. Contribution of T cell-mediated immunity to the resistance to staphlococcal infection

    International Nuclear Information System (INIS)

    Tsuda, S.; Sasai, Y.; Minami, K.; Nomoto, K.

    1978-01-01

    Abscess formation in nude mice after subcutaneous inoculation of Staphylococcus aureus (S. aureus) was more extensive and prolonged as compared with that in phenotypically normal littermates. Abscess formation in nude mice was augmented markedly by whole-body irradiation. Not only T cell-mediated immunity but also radiosensitive, nonimmune phagocytosis appear to contribute to the resistance against staphylococcal infection

  8. Intravital imaging reveals improved Kupffer cell-mediated phagocytosis as a mode of action of glycoengineered anti-CD20 antibodies.

    Science.gov (United States)

    Grandjean, Capucine L; Montalvao, Fabricio; Celli, Susanna; Michonneau, David; Breart, Beatrice; Garcia, Zacarias; Perro, Mario; Freytag, Olivier; Gerdes, Christian A; Bousso, Philippe

    2016-10-04

    Anti-CD20 monoclonal antibodies (mAbs) represent an effective treatment for a number of B cell malignancies and autoimmune disorders. Glycoengineering of anti-CD20mAb may contribute to increased anti-tumor efficacy through enhanced antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADP) as reported by in vitro studies. However, where and how glycoengineered Ab may potentiate therapeutic responses in vivo is yet to be elucidated. Here, we have performed mouse liver transplants to demonstrate that the liver is sufficient to mediate systemic B cells depletion after anti-CD20 treatment. Relying on intravital two-photon imaging of human CD20-expressing mice, we provide evidence that ADP by Kupffer cells (KC) is a major mechanism for rituximab-mediated B cell depletion. Notably, a glycoengineered anti-mouse CD20 Ab but not its wild-type counterpart triggered potent KC-mediated B cell depletion at low doses. Finally, distinct thresholds for KC phagocytosis were also observed for GA101 (obinutuzumab), a humanized glycoengineered type II anti-CD20 Ab and rituximab. Thus, we propose that enhanced phagocytosis of circulating B cells by KC represents an important in vivo mechanism underlying the improved activity of glycoengineered anti-CD20 mAbs.

  9. Secondary infection as a risk factor for dengue hemorrhagic fever/dengue shock syndrome: an historical perspective and role of antibody-dependent enhancement of infection.

    Science.gov (United States)

    Guzman, Maria G; Alvarez, Mayling; Halstead, Scott B

    2013-07-01

    Today, dengue viruses are the most prevalent arthropod-borne viruses in the world. Since the 1960s, numerous reports have identified a second heterologous dengue virus (DENV) infection as a principal risk factor for severe dengue disease (dengue hemorrhagic fever/dengue shock syndrome, DHF/DSS). Modifiers of dengue disease response include the specific sequence of two DENV infections, the interval between infections, and contributions from the human host, such as age, ethnicity, chronic illnesses and genetic background. Antibody-dependent enhancement (ADE) of dengue virus infection has been proposed as the early mechanism underlying DHF/DSS. Dengue cross-reactive antibodies raised following a first dengue infection combine with a second infecting virus to form infectious immune complexes that enter Fc-receptor-bearing cells. This results in an increased number of infected cells and increased viral output per cell. At the late illness stage, high levels of cytokines, possibly the result of T cell elimination of infected cells, result in vascular permeability, leading to shock and death. This review is focused on the etiological role of secondary infections (SI) and mechanisms of ADE.

  10. Fcγ-receptor IIa-mediated Src Signaling Pathway Is Essential for the Antibody-Dependent Enhancement of Ebola Virus Infection.

    Directory of Open Access Journals (Sweden)

    Wakako Furuyama

    2016-12-01

    Full Text Available Antibody-dependent enhancement (ADE of Ebola virus (EBOV infection has been demonstrated in vitro, raising concerns about the detrimental potential of some anti-EBOV antibodies. ADE has been described for many viruses and mostly depends on the cross-linking of virus-antibody complexes to cell surface Fc receptors, leading to enhanced infection. However, little is known about the molecular mechanisms underlying this phenomenon. Here we show that Fcγ-receptor IIa (FcγRIIa-mediated intracellular signaling through Src family protein tyrosine kinases (PTKs is required for ADE of EBOV infection. We found that deletion of the FcγRIIa cytoplasmic tail abolished EBOV ADE due to decreased virus uptake into cellular endosomes. Furthermore, EBOV ADE, but not non-ADE infection, was significantly reduced by inhibition of the Src family protein PTK pathway, which was also found to be important to promote phagocytosis/macropinocytosis for viral uptake into endosomes. We further confirmed a significant increase of the Src phosphorylation mediated by ADE. These data suggest that antibody-EBOV complexes bound to the cell surface FcγRIIa activate the Src signaling pathway that leads to enhanced viral entry into cells, providing a novel perspective for the general understanding of ADE of virus infection.

  11. Substitution of the precursor peptide prevents anti-prM antibody-mediated antibody-dependent enhancement of dengue virus infection.

    Science.gov (United States)

    Wang, Ying; Si, Lu-Lu; Guo, Xiao-Lan; Cui, Guo-Hui; Fang, Dan-Yun; Zhou, Jun-Mei; Yan, Hui-Jun; Jiang, Li-Fang

    2017-02-02

    Antibody-dependent enhancement (ADE) is currently considered as the mechanism underlying the pathogenesis of severe dengue disease. Many studies have shown that precursor (pr) peptide-specific antibodies do not efficiently neutralize infection but potently promote ADE of dengue virus (DENV) infection. To explore the effect of pr peptide substitution on neutralization and ADE of DENV infection, the rabbit anti-prM polyclonal antibodies (pAbs) and anti-JEVpr/DENV-M pAbs were prepared, and the neutralization and ADE of these two pAbs were further compared. Here, we report that both anti-JEVpr/DENV-M and anti-prM pAbs exhibited broad cross-reactivity and only partial neutralization with four DENV serotypes and immature DENV. Rabbit anti-prM pAbs showed a significant enhancement in a broad range of serum dilutions. However, there was no statistically significant difference in the enhancing activity of rabbit anti-JEVpr/DENV-M pAbs at various levels of dilution. These results demonstrate that anti-prM antibody-mediated ADE can be prevented by JEV pr peptide replacement. The present study contribute further to research on the pathogenesis of DENV infection. Copyright © 2016. Published by Elsevier B.V.

  12. Biodegradable nanoparticle delivery of inactivated swine influenza virus vaccine provides heterologous cell-mediated immune response in pigs.

    Science.gov (United States)

    Dhakal, Santosh; Hiremath, Jagadish; Bondra, Kathryn; Lakshmanappa, Yashavanth S; Shyu, Duan-Liang; Ouyang, Kang; Kang, Kyung-Il; Binjawadagi, Basavaraj; Goodman, Jonathan; Tabynov, Kairat; Krakowka, Steven; Narasimhan, Balaji; Lee, Chang Won; Renukaradhya, Gourapura J

    2017-02-10

    Swine influenza virus (SwIV) is one of the important zoonotic pathogens. Current flu vaccines have failed to provide cross-protection against evolving viruses in the field. Poly(lactic-co-glycolic acid) (PLGA) is a biodegradable FDA approved polymer and widely used in drug and vaccine delivery. In this study, inactivated SwIV H1N2 antigens (KAg) encapsulated in PLGA nanoparticles (PLGA-KAg) were prepared, which were spherical in shape with 200 to 300nm diameter, and induced maturation of antigen presenting cells in vitro. Pigs vaccinated twice with PLGA-KAg via intranasal route showed increased antigen specific lymphocyte proliferation and enhanced the frequency of T-helper/memory and cytotoxic T cells (CTLs) in peripheral blood mononuclear cells (PBMCs). In PLGA-KAg vaccinated and heterologous SwIV H1N1 challenged pigs, clinical flu symptoms were absent, while the control pigs had fever for four days. Grossly and microscopically, reduced lung pathology and viral antigenic mass in the lung sections with clearance of infectious challenge virus in most of the PLGA-KAg vaccinated pig lung airways were observed. Immunologically, PLGA-KAg vaccine irrespective of not significantly boosting the mucosal antibody response, it augmented the frequency of IFN-γ secreting total T cells, T-helper and CTLs against both H1N2 and H1N1 SwIV. In summary, inactivated influenza virus delivered through PLGA-NPs reduced the clinical disease and induced cross-protective cell-mediated immune response in a pig model. Our data confirmed the utility of a pig model for intranasal particulate flu vaccine delivery platform to control flu in humans. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Modulation of Dengue/Zika Virus Pathogenicity by Antibody-Dependent Enhancement and Strategies to Protect Against Enhancement in Zika Virus Infection

    Directory of Open Access Journals (Sweden)

    Rekha Khandia

    2018-04-01

    Full Text Available Antibody-dependent enhancement (ADE is a phenomenon in which preexisting poorly neutralizing antibodies leads to enhanced infection. It is a serious concern with mosquito-borne flaviviruses such as Dengue virus (DENV and Zika virus (ZIKV. In vitro experimental evidences have indicated the preventive, as well as a pathogenicity-enhancing role, of preexisting DENV antibodies in ZIKV infections. ADE has been confirmed in DENV but not ZIKV infections. Principally, the Fc region of the anti-DENV antibody binds with the fragment crystallizable gamma receptor (FcγR, and subsequent C1q interactions and immune effector functions are responsible for the ADE. In contrast to normal DENV infections, with ADE in DENV infections, inhibition of STAT1 phosphorylation and a reduction in IRF-1 gene expression, NOS2 levels, and RIG-1 and MDA-5 expression levels occurs. FcγRIIA is the most permissive FcγR for DENV-ADE, and under hypoxic conditions, hypoxia-inducible factor-1 alpha transcriptionally enhances expression levels of FcγRIIA, which further enhances ADE. To produce therapeutic antibodies with broad reactivity to different DENV serotypes, as well as to ZIKV, bispecific antibodies, Fc region mutants, modified Fc regions, and anti-idiotypic antibodies may be engineered. An in-depth understanding of the immunological and molecular mechanisms of DENV-ADE of ZIKV pathogenicity will be useful for the design of common and safe therapeutics and prophylactics against both viral pathogens. The present review discusses the role of DENV antibodies in modulating DENV/ZIKV pathogenicity/infection and strategies to counter ADE to protect against Zika infection.

  14. Viral Load and Cytokine Response Profile Does Not Support Antibody-Dependent Enhancement in Dengue-Primed Zika Virus-Infected Patients.

    Science.gov (United States)

    Terzian, Ana Carolina Bernardes; Schanoski, Alessandra Soares; Mota, Mânlio Tasso de Oliveira; da Silva, Rafael Alves; Estofolete, Cássia Fernanda; Colombo, Tatiana Elias; Rahal, Paula; Hanley, Kathryn A; Vasilakis, Nikos; Kalil, Jorge; Nogueira, Maurício Lacerda

    2017-10-15

    The pathogenesis of severe dengue disease involves immune components as biomarkers. The mechanism by which some dengue virus (DENV)-infected individuals progress to severe disease is poorly understood. Most studies on the pathogenesis of severe dengue disease focus on the process of antibody-dependent enhancement (ADE) as a primary risk factor. With the circulation of Zika virus (ZIKV) in DENV-endemic areas, many people infected by ZIKV were likely exposed to DENV. The influence of such exposure on Zika disease outcomes remains unknown. We investigated whether patients previously exposed to DENV exhibited higher viremia when exposed to a subsequent, heterologous dengue or Zika infection than those patients not previously exposed to dengue. We measured viral loads and cytokine profile during patients' acute infections. Neither dengue nor Zika viremia was higher in patients with prior DENV infection, although the power to detect such a difference was only adequate in the ZIKV analysis. Of the 10 cytokines measured, only 1 significant difference was detected: Levels of interleukin 1β (IL-1β) were lower in dengue-infected patients who had experienced a previous dengue infection than patients infected with dengue for the first time. However, power to detect differences between groups was low. In Zika-infected patients, levels of IL-1β showed a significant, positive correlation with viral load. No signs of ADE were observed in vivo in patients with acute ZIKV infection who had prior exposure to DENV. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  15. Sulfated polysaccharide, curdlan sulfate, efficiently prevents entry/fusion and restricts antibody-dependent enhancement of dengue virus infection in vitro: a possible candidate for clinical application.

    Directory of Open Access Journals (Sweden)

    Koji Ichiyama

    Full Text Available Curdlan sulfate (CRDS, a sulfated 1→3-β-D glucan, previously shown to be a potent HIV entry inhibitor, is characterized in this study as a potent inhibitor of the Dengue virus (DENV. CRDS was identified by in silico blind docking studies to exhibit binding potential to the envelope (E protein of the DENV. CRDS was shown to inhibit the DENV replication very efficiently in different cells in vitro. Minimal effective concentration of CRDS was as low as 0.1 µg/mL in LLC-MK2 cells, and toxicity was observed only at concentrations over 10 mg/mL. CRDS can also inhibit DENV-1, 3, and 4 efficiently. CRDS did not inhibit the replication of DENV subgenomic replicon. Time of addition experiments demonstrated that the compound not only inhibited viral infection at the host cell binding step, but also at an early post-attachment step of entry (membrane fusion. The direct binding of CRDS to DENV was suggested by an evident reduction in the viral titers after interaction of the virus with CRDS following an ultrafiltration device separation, as well as after virus adsorption to an alkyl CRDS-coated membrane filter. The electron microscopic features also showed that CRDS interacted directly with the viral envelope, and caused changes to the viral surface. CRDS also potently inhibited DENV infection in DC-SIGN expressing cells as well as the antibody-dependent enhancement of DENV-2 infection. Based on these data, a probable binding model of CRDS to DENV E protein was constructed by a flexible receptor and ligand docking study. The binding site of CRDS was predicted to be at the interface between domains II and III of E protein dimer, which is unique to this compound, and is apparently different from the β-OG binding site. Since CRDS has already been tested in humans without serious side effects, its clinical application can be considered.

  16. Dengue virus specific IgY provides protection following lethal dengue virus challenge and is neutralizing in the absence of inducing antibody dependent enhancement.

    Directory of Open Access Journals (Sweden)

    Ashley L Fink

    2017-07-01

    Full Text Available Dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS are severe disease manifestations that can occur following sequential infection with different dengue virus serotypes (DENV1-4. At present, there are no licensed therapies to treat DENV-induced disease. DHF and DSS are thought to be mediated by serotype cross-reactive antibodies that facilitate antibody-dependent enhancement (ADE by binding to viral antigens and then Fcγ receptors (FcγR on target myeloid cells. Using genetically engineered DENV-specific antibodies, it has been shown that the interaction between the Fc portion of serotype cross-reactive antibodies and FcγR is required to induce ADE. Additionally, it was demonstrated that these antibodies were as neutralizing as their non-modified variants, were incapable of inducing ADE, and were therapeutic following a lethal, antibody-enhanced infection. Therefore, we hypothesized that avian IgY, which do not interact with mammalian FcγR, would provide a novel therapy for DENV-induced disease. We demonstrate here that goose-derived anti-DENV2 IgY neutralized DENV2 and did not induce ADE in vitro. Anti-DENV2 IgY was also protective in vivo when administered 24 hours following a lethal DENV2 infection. We were also able to demonstrate via epitope mapping that both full-length and alternatively spliced anti-DENV2 IgY recognized different epitopes, including epitopes that have not been previously identified. These observations provide evidence for the potential therapeutic applications of goose-derived anti-DENV2 IgY.

  17. Lipidated dengue-2 envelope protein domain III independently stimulates long-lasting neutralizing antibodies and reduces the risk of antibody-dependent enhancement.

    Directory of Open Access Journals (Sweden)

    Chen-Yi Chiang

    Full Text Available BACKGROUND: Dengue virus is a mosquito-transmitted virus that can cause self-limiting dengue fever, severe life-threatening dengue hemorrhagic fever and dengue shock syndrome. The existence of four serotypes of dengue virus has complicated the development of an effective and safe dengue vaccine. Recently, a clinical phase 2b trial of Sanofi Pasteur's CYD tetravalent dengue vaccine revealed that the vaccine did not confer full protection against dengue-2 virus. New approaches to dengue vaccine development are urgently needed. Our approach represents a promising method of dengue vaccine development and may even complement the deficiencies of the CYD tetravalent dengue vaccine. METHODOLOGY/PRINCIPAL FINDINGS: Two important components of a vaccine, the immunogen and immunopotentiator, were combined into a single construct to generate a new generation of vaccines. We selected dengue-2 envelope protein domain III (D2ED III as the immunogen and expressed this protein in lipidated form in Escherichia coli, yielding an immunogen with intrinsic immunopotentiation activity. The formulation containing lipidated D2ED III (LD2ED III in the absence of exogenous adjuvant elicited higher D2ED III-specific antibody responses than those obtained from its nonlipidated counterpart, D2ED III, and dengue-2 virus. In addition, the avidity and neutralizing capacity of the antibodies induced by LD2ED III were higher than those elicited by D2ED III and dengue-2 virus. Importantly, we showed that after lipidation, the subunit candidate LD2ED III exhibited increased immunogenicity while reducing the potential risk of antibody-dependent enhancement of infection in mice. CONCLUSIONS/SIGNIFICANCE: Our study suggests that the lipidated subunit vaccine approach could be applied to other serotypes of dengue virus and other pathogens.

  18. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    Energy Technology Data Exchange (ETDEWEB)

    Chotiwan, Nunya; Roehrig, John T. [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States); Schlesinger, Jacob J. [Department of Medicine, University of Rochester, Rochester, NY 14642 (United States); Blair, Carol D. [Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523 (United States); Huang, Claire Y.-H., E-mail: yxh0@cdc.gov [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States)

    2014-05-15

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection.

  19. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    International Nuclear Information System (INIS)

    Chotiwan, Nunya; Roehrig, John T.; Schlesinger, Jacob J.; Blair, Carol D.; Huang, Claire Y.-H.

    2014-01-01

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection

  20. Cell-mediated immunity as an early diagnostic test for osteosarcoma in human radium cases

    International Nuclear Information System (INIS)

    Lloyd, E.L.; Menon, M.; Mitchen, J.L.

    1976-01-01

    Lymphocytes from patients carrying a body burden greater than 0.3 μCi of 226 Ra have been tested for specific cytotoxicity to four different osteosarcoma cell lines as well as to normal human fibroblasts. Cytotoxicity indexes (defined as the ratio of the number of target cells remaining, after treatment with the patients' lymphocytes, relative to the values obtained with normal control subjects) have been calculated. With one exception no cytotoxicity was observed. This is in agreement with the fact that no fresh osteosarcomas were diagnosed. The patient in whom cytotoxicity was found was suffering from an inflammatory lesion involving bone as the result of a foreign-body reaction at the time of the first test. When the test was repeated 10 months later, no cytotoxicity was observed. No significant nonspecific cytotoxicity was observed when lymphocytes from normal control subjects were interacted with any of the target cell lines

  1. Recent Advances in Type-2-Cell-Mediated Immunity: Insights from Helminth Infection.

    Science.gov (United States)

    Harris, Nicola L; Loke, P'ng

    2017-12-19

    Type-2-cell-mediated immune responses play a critical role in mediating both host-resistance and disease-tolerance mechanisms during helminth infections. Recently, type 2 cell responses have emerged as major regulators of tissue repair and metabolic homeostasis even under steady-state conditions. In this review, we consider how studies of helminth infection have contributed toward our expanding cellular and molecular understanding of type-2-cell-mediated immunity, as well as new areas such as the microbiome. By studying how these successful parasites form chronic infections without overt pathology, we are gaining additional insights into allergic and inflammatory diseases, as well as normal physiology. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Receptor binding and cell-mediated metabolism of [125I]monoiodoglucagon by isolated canine hepatocytes

    International Nuclear Information System (INIS)

    Hagopian, W.A.; Tager, H.S.

    1984-01-01

    A reverse-phase HPLC method has been developed to purify 125 I-labeled products resulting from the chloramine-T-based iodination of glucagon. In addition the products [( 125 I)iodoTyr 10 13 ]glucagon, [( 125 I)iodoTyr 13 ]glucagon, and [( 125 I)iodoTyr 10 ]glucagon) have been used to study the receptor binding of glucagon and the cell-mediated metabolism of the hormone by isolated canine hepatocytes. It was concluded that (a) not withstanding apparent differences in affinities exhibited by the three peptides, the interactions with the glucagon receptor are functionally equivalent, and (b) the cell-mediated metabolism of receptor-bound glucagon involves the formation of hormone-derived peptides in which the biologically important NH 2 -terminal region of the hormone has been modified by limited proteolytic cleavage

  3. Effect of microencapsulated ampicillin on cell-mediated immune responses in mice.

    Science.gov (United States)

    Barsoum, I S; Kopydlowski, K M; Burge, J R; Setterstrom, J A

    1997-11-01

    The effects of free ampicillin, microencapsulated ampicillin anhydrate (MEAA) and antibiotic-free microspheres on the cell-mediated immune response in Balb/c mice were measured by lymphoproliferation assay, delayed-type hypersensitivity (DTH) and cytokine production. Injection into mice for seven consecutive days with equivalent subcutaneous doses of ampicillin, MEAA or placebo microspheres did not produce any consistent change in lymphocyte proliferation nor did it affect DTH responses or interleukin-2 production. Although the production of interleukin-4 in mice treated with ampicillin or MEAA increased compared with the control mice, this increase was not statistically significant. These results indicate that ampicillin and MEAA have similar effects on cell-mediated immunity in mice.

  4. Challenges and opportunities for T cell-mediated strategies to eliminate HIV reservoirs

    Directory of Open Access Journals (Sweden)

    Mark Alan Brockman

    2015-10-01

    Full Text Available HIV’s ability to establish latent reservoirs of reactivation-competent virus is the major barrier to cure. Shock and kill methods consisting of latency reversing agents (LRAs followed by elimination of reactivating cells through cytopathic effects are under active development. However, the clinical efficacy of LRAs remains to be established. Moreover, recent studies indicate that reservoirs may not be reduced efficiently by either viral cytopathic or CD8+ T-cell-mediated mechanisms. In this perspective, we highlight challenges to T-cell-mediated elimination of HIV reservoirs, including characteristics of responding T-cells, aspects of the cellular reservoirs and properties of the latent virus itself. We also discuss potential strategies to overcome these challenges by targeting the antiviral activity of T-cells towards appropriate viral antigens following latency.

  5. Cell-mediated allergy to cerebral aneurysm clip causing extensive cerebral edema.

    Science.gov (United States)

    Tan, Terence; Tee, Jin W; Han, Tiew F

    2014-10-01

    The authors report the first case of vasogenic cerebral edema due to a cell-mediated hypersensitivity reaction to a nickel-containing aneurysm clip. The patient initially presented for elective clipping of a right middle cerebral artery aneurysm, and on long-term follow-up she demonstrated relapsing-remitting cerebral edema. Four years post-aneurysm clipping, she underwent an exploratory craniotomy given unsuccessful conservative management of her headaches and imaging evidence of cerebral edema with mass effect. During surgery, gross parenchymal edema and inflammatory nodules were observed. Histopathology was consistent with a cell-mediated (Type IV) hypersensitivity reaction. Concerns regarding nickel allergy are often reported in the cardiac literature. This case highlights the possibility of nickel hypersensitivity when using nickel-containing aneurysm clips, especially in patients with known nickel allergies.

  6. Role of very late antigen-1 in T-cell-mediated immunity to systemic viral infection

    DEFF Research Database (Denmark)

    Ørding Kauffmann, Susanne; Thomsen, Allan Randrup; Christensen, Jan Pravsgaard

    2006-01-01

    The T-cell response to lymphocytic choriomeningitis virus was studied in mice lacking very late antigen-1 (VLA-1). The generation of virus-specific effector T cells was unimpaired in VLA-1(-/-) mice. In the memory phase, VLA-1 deficiency did not influence the number of memory CD8(+) T cells or th......, the current findings indicate that the expression of VLA-1 is not pivotal for T-cell-mediated antiviral immunity to a systemic infection....... or their distribution between lymphoid and nonlymphoid organs. Regarding a functional role of VLA-1, we found that intracerebral infection of both VLA-1(-/-) and wild-type (wt) mice resulted in lethal T-cell-mediated meningitis, and quantitative and qualitative analyses of the cellular exudate did not reveal any...

  7. Saos-2 cell-mediated mineralization on collagen gels: Effect of densification and bioglass incorporation.

    Science.gov (United States)

    Liu, Gengbo; Pastakia, Meet; Fenn, Michael B; Kishore, Vipuil

    2016-05-01

    Plastic compression is a collagen densification process that has been widely used for the development of mechanically robust collagen-based materials. Incorporation of bioglass within plastically compressed collagen gels has been shown to mimic the microstructural properties of native bone and enhance in vitro cell-mediated mineralization. The current study seeks to decouple the effects of collagen densification and bioglass incorporation to understand the interplay between collagen packing density and presence of bioglass on cell-mediated mineralization. Saos-2 cell-mediated mineralization was assessed as a measure of the osteoconductivity of four different collagen gels: (1) uncompressed collagen gel (UC), (2) bioglass incorporated uncompressed collagen gel (UC + BG), (3) plastically compressed collagen gel (PC), and (4) bioglass incorporated plastically compressed collagen gel (PC + BG). The results indicated that collagen densification enhanced mineralization as shown by SEM, increased alkaline phosphatase activity and produced significantly higher amounts of mineralized nodules on PC gels compared to UC gels. Further, the amount of nodule formation on PC gels was significantly higher compared to UC + BG gels indicating that increase in matrix stiffness due to collagen densification had a greater effect on cell-mediated mineralization compared to bioglass incorporation into loosely packed UC gels. Incorporation of bioglass into PC gels further enhanced mineralization as evidenced by significantly larger nodule size and higher amount of mineralization on PC + BG gels compared to PC gels. In conclusion, collagen densification via plastic compression improves the osteoconductivity of collagen gels. Further, incorporation of bioglass within PC gels has an additive effect and further enhances the osteoconductivity of collagen gels. © 2016 Wiley Periodicals, Inc.

  8. Cell-mediated immune response in rotavirus-infected calves: leucocyte migration inhibition assay.

    Science.gov (United States)

    Chauhan, R S; Singh, N P

    1992-07-01

    The cell-mediated immune (CMI) response was determined in rotavirus-infected calves by leucocyte migration inhibition assay with blood, spleen, mesenteric lymph node and intestinal lymphocytes. The inhibition of migration was more prominent in intestinal and mesenteric lymph node lymphocytes than in spleen and blood. In rotavirus-infected calves, the assay indicated the presence of CMI response which was more prominent at the local site of infection.

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

    Science.gov (United States)

    Makinde, A A; Wilkie, B N

    1979-01-01

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

  10. Subversion of early innate antiviral responses during antibody-dependent enhancement of Dengue virus infection induces severe disease in immunocompetent mice.

    Science.gov (United States)

    Costa, Vivian V; Fagundes, Caio T; Valadão, Deborah F; Ávila, Thiago V; Cisalpino, Daniel; Rocha, Rebeca F; Ribeiro, Lucas S; Ascenção, Fernando R; Kangussu, Lucas M; Celso, M Q; Astigarraga, Ruiz G; Gouveia, Frederico L; Silva, Tarcília A; Bonaventura, Daniela; Sampaio, Divaldo de Almeida; Leite, Ana Cristina L; Teixeira, Mauro M; Souza, Danielle G

    2014-08-01

    Dengue is a mosquito-borne disease caused by one of four serotypes of Dengue virus (DENV-1-4). Epidemiologic and observational studies demonstrate that the majority of severe dengue cases, dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS), occurs predominantly in either individuals with cross-reactive immunity following a secondary heterologous infection or in infants with primary DENV infections born from dengue-immune mothers, suggesting that B-cell-mediated and antibody responses impact on disease evolution. We demonstrate here that B cells play a pivotal role in host responses against primary DENV infection in mice. After infection, μMT(-/-) mice showed increased viral loads followed by severe disease manifestation characterized by intense thrombocytopenia, hemoconcentration, cytokine production and massive liver damage that culminated in death. In addition, we show that poly and monoclonal anti-DENV-specific antibodies can sufficiently increase viral replication through a suppression of early innate antiviral responses and enhance disease manifestation, so that a mostly non-lethal illness becomes a fatal disease resembling human DHF/DSS. Finally, treatment with intravenous immunoglobulin containing anti-DENV antibodies confirmed the potential enhancing capacity of subneutralizing antibodies to mediate virus infection and replication and induce severe disease manifestation of DENV-infected mice. Thus, our results show that humoral responses unleashed during DENV infections can exert protective or pathological outcomes and provide insight into the pathogenesis of this important human pathogen.

  11. Flow cytometric readout based on Mitotracker Red CMXRos staining of live asexual blood stage malarial parasites reliably assesses antibody dependent cellular inhibition

    Directory of Open Access Journals (Sweden)

    Jogdand Prajakta S

    2012-07-01

    Full Text Available Abstract Background Functional in vitro assays could provide insights into the efficacy of malaria vaccine candidates. For estimating the anti-parasite effect induced by a vaccine candidate, an accurate determination of live parasite count is an essential component of most in vitro bioassays. Although traditionally parasites are counted microscopically, a faster, more accurate and less subjective method for counting parasites is desirable. In this study mitochondrial dye (Mitotracker Red CMXRos was used for obtaining reliable live parasite counts through flow cytometry. Methods Both asynchronous and tightly synchronized asexual blood stage cultures of Plasmodium falciparum were stained with CMXRos and subjected to detection by flow cytometry and fluorescence microscopy. The parasite counts obtained by flow cytometry were compared to standard microscopic counts obtained through examination of Giemsa-stained thin smears. A comparison of the ability of CMXRos to stain live and compromised parasites (induced by either medium starvation or by anti-malarial drug treatment was carried out. Finally, parasite counts obtained by CMXRos staining through flow cytometry were used to determine specific growth inhibition index (SGI in an antibody-dependent cellular inhibition (ADCI assay. Results Mitotracker Red CMXRos can reliably detect live intra-erythrocytic stages of P. falciparum. Comparison between staining of live with compromised parasites shows that CMXRos predominantly stains live parasites with functional mitochondria. Parasite counts obtained by CMXRos staining and flow cytometry were highly reproducible and can reliably determine the ability of IgG from hyper-immune individuals to inhibit parasite growth in presence of monocytes in ADCI assay. Further, a dose-dependent parasite growth inhibitory effect could be detected for both total IgG purified from hyper-immune sera and affinity purified IgGs against the N-terminal non-repeat region of GLURP

  12. Flow cytometric readout based on Mitotracker Red CMXRos staining of live asexual blood stage malarial parasites reliably assesses antibody dependent cellular inhibition.

    Science.gov (United States)

    Jogdand, Prajakta S; Singh, Susheel K; Christiansen, Michael; Dziegiel, Morten H; Singh, Subhash; Theisen, Michael

    2012-07-20

    Functional in vitro assays could provide insights into the efficacy of malaria vaccine candidates. For estimating the anti-parasite effect induced by a vaccine candidate, an accurate determination of live parasite count is an essential component of most in vitro bioassays. Although traditionally parasites are counted microscopically, a faster, more accurate and less subjective method for counting parasites is desirable. In this study mitochondrial dye (Mitotracker Red CMXRos) was used for obtaining reliable live parasite counts through flow cytometry. Both asynchronous and tightly synchronized asexual blood stage cultures of Plasmodium falciparum were stained with CMXRos and subjected to detection by flow cytometry and fluorescence microscopy. The parasite counts obtained by flow cytometry were compared to standard microscopic counts obtained through examination of Giemsa-stained thin smears. A comparison of the ability of CMXRos to stain live and compromised parasites (induced by either medium starvation or by anti-malarial drug treatment) was carried out. Finally, parasite counts obtained by CMXRos staining through flow cytometry were used to determine specific growth inhibition index (SGI) in an antibody-dependent cellular inhibition (ADCI) assay. Mitotracker Red CMXRos can reliably detect live intra-erythrocytic stages of P. falciparum. Comparison between staining of live with compromised parasites shows that CMXRos predominantly stains live parasites with functional mitochondria. Parasite counts obtained by CMXRos staining and flow cytometry were highly reproducible and can reliably determine the ability of IgG from hyper-immune individuals to inhibit parasite growth in presence of monocytes in ADCI assay. Further, a dose-dependent parasite growth inhibitory effect could be detected for both total IgG purified from hyper-immune sera and affinity purified IgGs against the N-terminal non-repeat region of GLURP in ADCI assays coupled with determination of

  13. Pichia pastoris-Expressed Bivalent Virus-Like Particulate Vaccine Induces Domain III-Focused Bivalent Neutralizing Antibodies without Antibody-Dependent Enhancement in Vivo

    Directory of Open Access Journals (Sweden)

    Rahul Shukla

    2018-01-01

    Full Text Available Dengue, a significant public health problem in several countries around the world, is caused by four different serotypes of mosquito-borne dengue viruses (DENV-1, -2, -3, and -4. Antibodies to any one DENV serotype which can protect against homotypic re-infection, do not offer heterotypic cross-protection. In fact, cross-reactive antibodies may augment heterotypic DENV infection through antibody-dependent enhancement (ADE. A recently launched live attenuated vaccine (LAV for dengue, which consists of a mixture of four chimeric yellow-fever/dengue vaccine viruses, may be linked to the induction of disease-enhancing antibodies. This is likely related to viral interference among the replicating viral strains, resulting in an unbalanced immune response, as well as to the fact that the LAV encodes prM, a DENV protein documented to elicit ADE-mediating antibodies. This makes it imperative to explore the feasibility of alternate ADE risk-free vaccine candidates. Our quest for a non-replicating vaccine centered on the DENV envelope (E protein which mediates virus entry into the host cell and serves as an important target of the immune response. Serotype-specific neutralizing epitopes and the host receptor recognition function map to E domain III (EDIII. Recently, we found that Pichia pastoris-expressed DENV E protein, of all four serotypes, self-assembled into virus-like particles (VLPs in the absence of prM. Significantly, these VLPs displayed EDIII and elicited EDIII-focused DENV-neutralizing antibodies in mice. We now report the creation and characterization of a novel non-replicating recombinant particulate vaccine candidate, produced by co-expressing the E proteins of DENV-1 and DENV-2 in P. pastoris. The two E proteins co-assembled into bivalent mosaic VLPs (mVLPs designated as mE1E2bv VLPs. The mVLP, which preserved the serotype-specific antigenic integrity of its two component proteins, elicited predominantly EDIII-focused homotypic virus

  14. Evidence for the protective effect of maternal FcR-blocking IgG alloantibodies HLA-DR in Rh D-haemolytic disease of the newborn

    NARCIS (Netherlands)

    Dooren, M. C.; van Kamp, I. L.; Kanhai, H. H.; Gravenhorst, J. B.; von dem Borne, A. E.; Engelfriet, C. P.

    1993-01-01

    In cases of Rh D alloimmunization, strong results in the antibody-dependent cell-mediated cytotoxicity (ADCC) assay (> 80% lysis as compared to that of the standard anti-D serum) are indicative of severe hemolytic disease to occur in the newborn (HDN). However, discrepant cases were found in which

  15. Cell-mediated immunity against human retinal extract, S-antigen, and interphotoreceptor retinoid binding protein in onchocercal chorioretinopathy

    NARCIS (Netherlands)

    van der Lelij, A.; Rothova, A.; Stilma, J. S.; Hoekzema, R.; Kijlstra, A.

    1990-01-01

    Autoimmune mechanisms are thought to be involved in the pathogenesis of onchocercal chorioretinopathy. Cell-mediated immune responses to human retinal S-antigen, interphotoreceptor retinoid binding protein (IRBP), and crude retinal extract were investigated in patients with onchocerciasis from

  16. A Novel Mechanism of Estrogen Action in Breast Cancer Cells Mediated Through ER-FE65 Complex Formation

    Science.gov (United States)

    2013-03-01

    breast cancer cells mediated through ER-FE65 complex formation PRINCIPAL INVESTIGATOR: Wenlong Bai, Ph.D. CONTRACTING ORGANIZATION...breast cancer cells mediated through ER-FE65 complex formation 5b. GRANT NUMBER W81XWH-09-1-0574 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...above information, we proposed a novel function for Fe65 in breast cancer cells . We hypothesize that Fe65 functions as a dual adaptor for ERα and

  17. 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

  18. [T cell-mediated immune responses and the recognition of tuberculosis antigens].

    Science.gov (United States)

    Tsujimura, Kunio; Koide, Yukio

    2010-06-01

    T cell-mediated immune responses profoundly contribute to the protection against the re-activation of latently infected Mycobacterium tuberculosis. Th1 cells produce IFN-gamma to activate infected macrophages and promote the formation of granulomas around infected macrophages. CD8+, gamma delta and CD1-restricted T cells also produce IFN-gamma and participate the protective responses against bacterial growth. Th17 cells produce IL-17 to promote the mobilization of immunocompetent cells and contribute to the granuloma formation. On the contrary, Th2 cells and Tregs interfere these protective immune responses.

  19. Dendritic cell-mediated-immunization with xenogenic PrP and adenoviral vectors breaks tolerance and prolongs mice survival against experimental scrapie.

    Directory of Open Access Journals (Sweden)

    Martine Bruley Rosset

    Full Text Available In prion diseases, PrP(c, a widely expressed protein, is transformed into a pathogenic form called PrP(Sc, which is in itself infectious. Antibodies directed against PrP(c have been shown to inhibit PrP(c to PrP(Sc conversion in vitro and protect in vivo from disease. Other effectors with potential to eliminate PrPSc-producing cells are cytotoxic T cells directed against PrP-derived peptides but their ability to protect or to induce deleterious autoimmune reactions is not known. The natural tolerance to PrP(c makes difficult to raise efficient adaptive responses. To break tolerance, adenovirus (Ad encoding human PrP (hPrP or control Ad were administered to wild-type mice by direct injection or by transfer of Ad-transduced dendritic cells (DCs. Control Ad-transduced DCs from Tg650 mice overexpressing hPrP were also used for immunization. DC-mediated but not direct administration of AdhPrP elicited antibodies that bound to murine native PrP(c. Frequencies of PrP-specific IFNgamma-secreting T cells were low and in vivo lytic activity only targeted cells strongly expressing hPrP. Immunohistochemical analysis revealed that CD3(+ T cell infiltration was similar in the brain of vaccinated and unvaccinated 139A-infected mice suggesting the absence of autoimmune reactions. Early splenic PrP(Sc replication was strongly inhibited ten weeks post infection and mean survival time prolonged from 209 days in untreated 139A-infected mice to 246 days in mice vaccinated with DCs expressing the hPrP. The efficacy appeared to be associated with antibody but not with cytotoxic cell-mediated PrP-specific responses.

  20. NK cell-mediated killing of AML blasts. Role of histamine, monocytes and reactive oxygen metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Brune, M.; Mellqvist, U.H. [Sahlgren`s Univ. Hospital, Dept. of Medicine, Haematology Section, Goeteborg (Sweden); Hansson, M.; Hermodsson, S.; Hellstrand, K. [Sahlgren`s Univ. Hospital, Dept. of Virology, Goeteborg (Sweden)

    1996-10-01

    Blasts recovered from patients with acute myelogenous leukaemia (AML) were lysed by heterologeous natural killer (NK) cells treated with NK cell-activating cytokine-induced killing of AML blasts was inhibited by monocytes, recovered from peripheral blood by counterflow centrifugal elutriation. Histamine, at concentrations exceeding 0.1 {mu}M, abrogated the monocyte-induced inhibition of NK cells; thereby, histamine and IL-2 or histamine and IFN-{alpha} synergistically induced NK cell-mediated destruction of AML blasts. The effect of histamine was completely blocked by the histamine H2-receptor (H2R) antagonist ranitidine but not by its chemical control AH20399AA. Catalase, a scavenger of reactive oxygen metabolites (ROM), reversed the monocyte-induced inhibition of NK cell-mediated killing of blast cells, indicating that the inhibitory signal was mediated by products of the respiratory burst of monocytes. It is concluded that (i) monocytes inhibit anti-leukemic properties of NK cells, (ii) the inhibition is conveyed by monocyte-derived ROM, and (iii) histamine reverses the inhibitory signal and, thereby, synergizes with NK cell-activating cytokines to induce killing of AML blasts. (au) 19 refs.

  1. Role of T-cell-mediated inflammation in psoriasis: pathogenesis and targeted therapy

    Directory of Open Access Journals (Sweden)

    Flatz L

    2013-02-01

    Full Text Available Lukas Flatz, Curdin ConradDepartment of Dermatology, University Hospital of Lausanne (CHUV, Lausanne, SwitzerlandAbstract: Psoriasis is one of the most common chronic, inflammatory, T-cell-mediated autoimmune diseases. Over the past decade, increased knowledge of disease pathogenesis has fundamentally changed psoriasis treatment, with the introduction of biologics, and this has led to a multitude of improved selective targets providing potential therapeutic options. Indeed, numerous pathogenesis-based treatments are currently in development, as psoriasis has also become increasingly relevant for proof-of-concept studies. The purpose of this review was to summarize current knowledge of psoriasis immunopathogenesis, focusing on the T-cell-mediated immune response and its initiation. The authors describe recent advances in psoriasis treatment and discuss pathogenesis-based therapies that are currently in development or which could be envisioned for the future. Although current biologics are well tolerated, several issues such as long-term efficacy, long-term safety, and high costs keep driving the search for new and better therapies. With further advances in understanding disease pathogenesis, more genomic data from psoriasis patients becoming available, and potentially the identification of autoantigens in psoriasis, current research should lead to the development of a growing arsenal of improved targeted treatments and to further breakthrough immunotherapies.Keywords: autoimmunity, autoimmune disease, immune response, immunopathogenesis

  2. The measurement of cell mediated immunity by radioimmunoassay in desensitizing treatment with acupoints for allergic asthma

    International Nuclear Information System (INIS)

    Zhou Ronglin; Luan Meiling; Wang Mingsuo; Liu Keliang

    1994-05-01

    Three mitogens consisted of PHA, PWM, LPS were used to activate lymphocytes. Lymphocyte transformation with radioisotope incorporation of 3 H-TdR was done in 20 patients with allergic asthma and 14 healthy persons as control groups. Cell mediated immune in these cases of desensitizing treatment with acupoints were studied. The experiments showed that the incorporation rates of 3 H-TdR, acupoints were studied. The experiments showed that the incorporation rates of 3 H-TdR, activated by PHA, PWM, LPS, of the allergic asthma patients were P>0.05, P 3 H-TdR in lymphocytes after desensitizing treatment with acupoints compared with that before the treatment tended to be normal. Lymphocyte transformation difference of 3 H-TdR incorporation rates between this group and A or B control groups was significant (P<0.01). This study provides scientific clinical experimental evidences for researching cell mediated immune in attack and curative effects of allergic asthma

  3. An Interventional Study Using Cell-Mediated Immunity to Personalize Therapy for Cytomegalovirus Infection After Transplantation.

    Science.gov (United States)

    Kumar, D; Mian, M; Singer, L; Humar, A

    2017-09-01

    Cell-mediated immune responses predict clinical cytomegalovirus (CMV) events but have not been adopted into routine practice due to lack of interventional studies. Our objective was to demonstrate the safety and feasibility of early discontinuation of antivirals based on the real-time measurement of CMV-specific cell-mediated immunity (CMI) in patients with CMV viremia. Transplant patients were enrolled at the onset of CMV viremia requiring antiviral therapy. CD8 T cell responses were determined using the Quantiferon-CMV assay, and results were used to guide subsequent management. A total of 27 patients (median viral load at onset 10 900 International Units/mL) were treated until viral load negative. At end of treatment, 14/27 (51.9%) had a positive CMV-CMI response and had antivirals discontinued. The remaining 13/27 (48.1%) patients had a negative CMV-CMI response and received 2 months of secondary antiviral prophylaxis. In those with a positive CMI and early discontinuation of antivirals, only a single patient experienced a low-level asymptomatic recurrence. In contrast, recurrence was observed in 69.2% of CMI-negative patients despite more prolonged antivirals (p = 0.001). In conclusion, this is the first study to demonstrate the feasibility and safety of real-time CMV-specific CMI assessment to guide changes to the management of CMV infection. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  4. The Role of Antioxidation and Immunomodulation in Postnatal Multipotent Stem Cell-Mediated Cardiac Repair

    Directory of Open Access Journals (Sweden)

    Johnny Huard

    2013-08-01

    Full Text Available Oxidative stress and inflammation play major roles in the pathogenesis of coronary heart disease including myocardial infarction (MI. The pathological progression following MI is very complex and involves a number of cell populations including cells localized within the heart, as well as cells recruited from the circulation and other tissues that participate in inflammatory and reparative processes. These cells, with their secretory factors, have pleiotropic effects that depend on the stage of inflammation and regeneration. Excessive inflammation leads to enlargement of the infarction site, pathological remodeling and eventually, heart dysfunction. Stem cell therapy represents a unique and innovative approach to ameliorate oxidative stress and inflammation caused by ischemic heart disease. Consequently, it is crucial to understand the crosstalk between stem cells and other cells involved in post-MI cardiac tissue repair, especially immune cells, in order to harness the beneficial effects of the immune response following MI and further improve stem cell-mediated cardiac regeneration. This paper reviews the recent findings on the role of antioxidation and immunomodulation in postnatal multipotent stem cell-mediated cardiac repair following ischemic heart disease, particularly acute MI and focuses specifically on mesenchymal, muscle and blood-vessel-derived stem cells due to their antioxidant and immunomodulatory properties.

  5. Cytotoxicity assay automation

    Science.gov (United States)

    Levinthal, E. C.; Payne, R. O.

    1971-01-01

    The design and construction of a system to automatically test HLP antigens are described. Major efforts were made to test and evaluate the performance of such a system, and compare its performance with nonautomatic tissue typing techniques. The system is based on the fluorochromatic cytotoxicity assay. Results show the system will work but is subject to malfunctions after a few samplings, and poses problems in showing correctly the necessary readings.

  6. Spleen cells of whole body x-irradiated W/Fu rats enhance tumor growth in vivo and non-specific cytotoxicity in vitro

    International Nuclear Information System (INIS)

    Moroson, H.; Schechter, M.; Herskovic, T.; Kurzman, I.; Rotman, M.; Friedenberg, R.

    1980-01-01

    This study was designed to investigate the influence of spleen cells of normal Wistar/Furth (W/Fu) rats obtained after whole body x-irradiation (WBI) upon mammary carcinoma growth in vivo, and cell mediated cytotoxicity against several target cells in vitro. The ME/H mammary carcinoma employed here originally arose spontaneously in a W/Fu rat, metastasizing to the retroperitoneal lymph node and lungs. It was found that surviving non-adherent spleen cells taken two days after 500R WBI cause enhanced tumor growth and metastases development in a Winn assay compared with nonadherent spleen cells from unirradiated controls. These cells were also enriched in granulocytes compared with controls. While the level of nonspecific cell mediated cytotoxicity was variable, it increased significantly following WBI of the spleen cell donor. Our results indicate that there are apparently two opposing effects shown by non-adherent spleen cells surviving WBI of normal W/Fu rats: enhancement of in vivo tumor growth; and enhancement of in vitro cell mediated cytotoxicity. A possible mechanism to explain these contrasting results is suggested

  7. The susceptibility to cytotoxic T lymphocyte mediated lysis of chemically induced sarcomas from immunodeficient and normal mice

    DEFF Research Database (Denmark)

    Svane, I M; Engel, A M; Thomsen, Allan Randrup

    1997-01-01

    the sensitivity to CTL mediated lysis and surface expression of the MHC class I molecule Ld of the tumour cells. Tumour cells incapable of in vitro presentation of viral antigen to specific cytotoxic T cells originated from tumours known from previous experiments to be readily accepted after transplantation...... tested for susceptibility to cytolysis by virus specific cytotoxic T cells. Tumour cells originating from tumours induced in immunocompetent C.B.-17 mice presented virus antigen more efficiently than tumour cells from immunodeficient SCID mice. No significant difference in virus antigen presentation...... was found between tumours from nude and nu/+ BALB/c mice. The sensitivity of target cells from the individual tumours to cytotoxic T lymphocyte (CTL) mediated lysis correlated negatively with their sensitivity to natural killer (NK) cell mediated lysis. There was a positive correlation between...

  8. A non-surgical approach for male germ cell mediated gene transmission through transgenesis.

    Science.gov (United States)

    Usmani, Abul; Ganguli, Nirmalya; Sarkar, Hironmoy; Dhup, Suveera; Batta, Suryaprakash R; Vimal, Manoj; Ganguli, Nilanjana; Basu, Sayon; Nagarajan, P; Majumdar, Subeer S

    2013-12-05

    Microinjection of foreign DNA in male pronucleus by in-vitro embryo manipulation is difficult but remains the method of choice for generating transgenic animals. Other procedures, including retroviral and embryonic stem cell mediated transgenesis are equally complicated and have limitations. Although our previously reported technique of testicular transgenesis circumvented several limitations, it involved many steps, including surgery and hemicastration, which carried risk of infection and impotency. We improved this technique further, into a two step non-surgical electroporation procedure, for making transgenic mice. In this approach, transgene was delivered inside both testes by injection and modified parameters of electroporation were used for in-vivo gene integration in germ cells. Using variety of constructs, germ cell integration of the gene and its transmission in progeny was confirmed by PCR, slot blot and immunohistochemical analysis. This improved technique is efficient, requires substantially less time and can be easily adopted by various biomedical researchers.

  9. Biomimetic and cell-mediated mineralization of hydroxyapatite by carrageenan functionalized graphene oxide.

    Science.gov (United States)

    Liu, Hongyan; Cheng, Ju; Chen, Fengjuan; Hou, Fengping; Bai, Decheng; Xi, Pinxian; Zeng, Zhengzhi

    2014-03-12

    In bone tissue engineering, it is imperative to design multifunctional biomaterials that can induce and assemble bonelike apatite that is close to natural bone. In this study, graphene oxide (GO) was functionalized by carrageenan. The resulting GO-carrageenan (GO-Car) composite was further used as a substrate for biomimetic and cell-mediated mineralization of hydroxyapatite (HA). It was confirmed that carrageenan on the GO surface facilitated the nucleation of HA. The observation of the effect of the GO-Car on the adhesion, morphology, and proliferation of MC3T3-E1 cells was investigated. In vitro studies clearly show the effectiveness of GO-Car in promoting HA mineralization and cell differentiation. The results of this study suggested that the GO-Car hybrid will be a promising material for bone regeneration and implantation.

  10. Immunotherapy: Shifting the Balance of Cell-Mediated Immunity and Suppression in Human Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, Jo A.; Jochems, Caroline [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Gulley, James L. [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Schlom, Jeffrey, E-mail: js141c@nih.gov; Tsang, Kwong Y. [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2012-12-11

    Active immunotherapy is dependent on the ability of the immune system to recognize and respond to tumors. Despite overwhelming evidence to support a cell-mediated immune response to prostate cancer, it is insufficient to eradicate the disease. This is likely due to a high level of suppression at the tumor site from a variety of sources, including immunosuppressive cells. Immune cells entering the tumor microenvironment may be inhibited directly by the tumor, stromal cells or other immune cells that have been induced to adopt a suppressive phenotype. The resurgence of interest in immunotherapy following the approval of sipuleucel-T and ipilimumab by the Food and Drug Administration has brought about new strategies for overcoming tumor-mediated suppression and bolstering anti-tumor responses. Improved understanding of the immune response to prostate cancer can lead to new combination therapies, such as the use of vaccine with small molecule and checkpoint inhibitors or other immunotherapies.

  11. Effect of Schizonepeta tenuifolia extract on mast cell-mediated immediate-type hypersensitivity in rats.

    Science.gov (United States)

    Shin, T Y; Jeong, H J; Jun, S M; Chae, H J; Kim, H R; Baek, S H; Kim, H M

    1999-11-01

    We investigated the effect of an aqueous extract of Schizonepeta tenuifolia (STAE) on mast cell-mediated immediate-type hypersensitivity. STAE inhibited systemic allergic reaction induced by compound 48/80 in rats dose-dependently. STAE also inhibited plasma histamine levels induced by compound 48/80. STAE inhibited local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. In addition, STAE does-dependently inhibited histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. However, STAE had a significant enhancing effect on anti-DNP IgE-induced tumor necrosis factor-alpha (TNF-alpha) production from RPMC. These results indicate that STAE inhibits immediate-type hypersensitivity and suggest that STAE can selectively activate the TNF-alpha production from RPMC.

  12. Cell-mediated fibre recruitment drives extracellular matrix mechanosensing in engineered fibrillar microenvironments

    Science.gov (United States)

    Baker, Brendon M.; Trappmann, Britta; Wang, William Y.; Sakar, Mahmut S.; Kim, Iris L.; Shenoy, Vivek B.; Burdick, Jason A.; Chen, Christopher S.

    2015-12-01

    To investigate how cells sense stiffness in settings structurally similar to native extracellular matrices, we designed a synthetic fibrous material with tunable mechanics and user-defined architecture. In contrast to flat hydrogel surfaces, these fibrous materials recapitulated cell-matrix interactions observed with collagen matrices including stellate cell morphologies, cell-mediated realignment of fibres, and bulk contraction of the material. Increasing the stiffness of flat hydrogel surfaces induced mesenchymal stem cell spreading and proliferation; however, increasing fibre stiffness instead suppressed spreading and proliferation for certain network architectures. Lower fibre stiffness permitted active cellular forces to recruit nearby fibres, dynamically increasing ligand density at the cell surface and promoting the formation of focal adhesions and related signalling. These studies demonstrate a departure from the well-described relationship between material stiffness and spreading established with hydrogel surfaces, and introduce fibre recruitment as a previously undescribed mechanism by which cells probe and respond to mechanics in fibrillar matrices.

  13. T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models.

    Science.gov (United States)

    Watson, Alan M; Klimstra, William B

    2017-04-11

    The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus.

  14. Modulations in cell-mediated immunity of Mytilus edulis following the 'Sea Empress' oil spill

    International Nuclear Information System (INIS)

    Dyrynda, E.A.; Dyrynda, P.E.J.; Ratcliffe, N.A.; Pipe, R.K.

    1997-01-01

    The 'Sea Empress' oil tanker grounded outside Milford Haven (Wales, UK) in February 1996, spilling ∼ 70,000 tonnes of crude oil and contaminating over 100 km of coastline, causing mass mortalities and strandings of at least 11 mollusc species. Intensive field monitoring commenced after the spill, examining immunity and hydrocarbon levels in the mussel, Mytilus edulis (Mollusca: Bivalvia), a commercially-harvested species which can accumulate contaminants. Comparisons of mussels from oiled and reference sites revealed significant modulations in cell-mediated immunity. Elevations in blood cell (haemocyte) numbers and decreases in superoxide generation and phagocytosis were identified in contaminated animals. The immune response of contaminated mussels gradually improved and generally showed no significant differences compared with clean mussels after 11 weeks. By then, total hydrocarbon content in contaminated mussels had declined by 70-90%, while polycyclic aromatic hydrocarbon content had decreased by over 90%. (author)

  15. Immunotherapy: Shifting the Balance of Cell-Mediated Immunity and Suppression in Human Prostate Cancer

    International Nuclear Information System (INIS)

    Tucker, Jo A.; Jochems, Caroline; Gulley, James L.; Schlom, Jeffrey; Tsang, Kwong Y.

    2012-01-01

    Active immunotherapy is dependent on the ability of the immune system to recognize and respond to tumors. Despite overwhelming evidence to support a cell-mediated immune response to prostate cancer, it is insufficient to eradicate the disease. This is likely due to a high level of suppression at the tumor site from a variety of sources, including immunosuppressive cells. Immune cells entering the tumor microenvironment may be inhibited directly by the tumor, stromal cells or other immune cells that have been induced to adopt a suppressive phenotype. The resurgence of interest in immunotherapy following the approval of sipuleucel-T and ipilimumab by the Food and Drug Administration has brought about new strategies for overcoming tumor-mediated suppression and bolstering anti-tumor responses. Improved understanding of the immune response to prostate cancer can lead to new combination therapies, such as the use of vaccine with small molecule and checkpoint inhibitors or other immunotherapies

  16. Cell-mediated mutagenesis and cell transformation of mammalian cells by chemical carcinogens

    International Nuclear Information System (INIS)

    Huberman, E.; Langenbach, R.

    1977-01-01

    We have developed a cell-mediated mutagenesis assay in which cells with the appropriate markers for mutagenesis are co-cultivated with either lethally irradiated rodent embryonic cells that can metabolize carcinogenic hydrocarbons or with primary rat liver cells that can metabolize chemicals carcinogenic to the liver. During co-cultivation, the reactive metabolites of the procarcinogen appear to be transmitted to the mutable cells and induce mutations in them. Assays of this type make it possible to demonstrate a relationship between carcinogenic potency of the chemicals and their ability to induce mutations in mammalian cells. In addition, by simultaneously comparing the frequencies of transformation and mutation induced in normal diploid hamster cells by benzo(a)pyrene (BP) and one of its metabolites, it is possible to estimate the genetic target size for cell transformation in vitro

  17. A longitudinal study of cell-mediated immunity in pigs infected with porcine parvovirus

    DEFF Research Database (Denmark)

    Ladekjaer-Mikkelsen, A.S.; Nielsen, Jens

    2002-01-01

    Porcine parvovirus (PPV) is an ubiquitous pathogen causing reproductive failure in swine. Protection against reproductive failure caused by acute PPV infection has commonly been related to the presence of specific antibodies in the dam. However, the role of cell-mediated immunity during chronic PPV......-mediated immune response, a longitudinal infection experiment was performed, using swine leukocyte antigens (SLA) class I characterized growing pigs (haplotype H7/H7). Pigs were intranasally inoculated with PPV at 0, 80, and 136 days. At predetermined time points, peripheral blood mononuclear cells (PBMC) were......-cell subset of PBMC proliferated in response to virus antigen, in keeping with the assumed role for these cells in immunological memory. This is, to our knowledge, the first indication of a cellular immune response following PPV infection. A weak CTL activity, which peaked on days 80 and 87, was observed...

  18. Daratumumab: a first-in-class CD38 monoclonal antibody for the treatment of multiple myeloma

    Directory of Open Access Journals (Sweden)

    Larysa Sanchez

    2016-06-01

    Full Text Available Abstract Daratumumab is a human monoclonal antibody that targets CD38, a cell surface protein that is overexpressed on multiple myeloma (MM cells. Preclinical studies have shown that daratumumab induces MM cell death through several mechanisms, including complement-dependent cytotoxicity (CDC, antibody-dependent cell-mediated cytotoxicity (ADCC, antibody-dependent cellular phagocytosis (ADCP, and apoptosis. Given the encouraging efficacy and acceptable safety profile of daratumumab demonstrated in clinical trials, daratumumab has emerged as a novel treatment option for myeloma and became the first monoclonal antibody approved by the FDA for the treatment of MM.

  19. A convergent and essential interneuron pathway for Mauthner-cell-mediated escapes.

    Science.gov (United States)

    Lacoste, Alix M B; Schoppik, David; Robson, Drew N; Haesemeyer, Martin; Portugues, Ruben; Li, Jennifer M; Randlett, Owen; Wee, Caroline L; Engert, Florian; Schier, Alexander F

    2015-06-01

    The Mauthner cell (M-cell) is a command-like neuron in teleost fish whose firing in response to aversive stimuli is correlated with short-latency escapes [1-3]. M-cells have been proposed as evolutionary ancestors of startle response neurons of the mammalian reticular formation [4], and studies of this circuit have uncovered important principles in neurobiology that generalize to more complex vertebrate models [3]. The main excitatory input was thought to originate from multisensory afferents synapsing directly onto the M-cell dendrites [3]. Here, we describe an additional, convergent pathway that is essential for the M-cell-mediated startle behavior in larval zebrafish. It is composed of excitatory interneurons called spiral fiber neurons, which project to the M-cell axon hillock. By in vivo calcium imaging, we found that spiral fiber neurons are active in response to aversive stimuli capable of eliciting escapes. Like M-cell ablations, bilateral ablations of spiral fiber neurons largely eliminate short-latency escapes. Unilateral spiral fiber neuron ablations shift the directionality of escapes and indicate that spiral fiber neurons excite the M-cell in a lateralized manner. Their optogenetic activation increases the probability of short-latency escapes, supporting the notion that spiral fiber neurons help activate M-cell-mediated startle behavior. These results reveal that spiral fiber neurons are essential for the function of the M-cell in response to sensory cues and suggest that convergent excitatory inputs that differ in their input location and timing ensure reliable activation of the M-cell, a feedforward excitatory motif that may extend to other neural circuits. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Hypoxia simultaneously alters satellite cell-mediated angiogenesis and hepatocyte growth factor expression.

    Science.gov (United States)

    Flann, K L; Rathbone, C R; Cole, L C; Liu, X; Allen, R E; Rhoads, R P

    2014-05-01

    Skeletal muscle regeneration is a multifaceted process requiring the spatial and temporal coordination of myogenesis as well as angiogenesis. Hepatocyte growth factor (HGF) plays a pivotal role in myogenesis by activating satellite cells (SC) in regenerating muscle and likely plays a role as a contributor to revascularization. Moreover, repair of a functional blood supply is critical to ameliorate tissue ischemia and restore skeletal muscle function, however effects of hypoxia on satellite cell-mediated angiogenesis remain unclear. The objective of this study was to examine the role of HGF and effect of hypoxia on the capacity of satellite cells to promote angiogenesis. To characterize the role of HGF, a microvascular fragment (MVF) culture model coupled with satellite cell conditioned media (CM) was employed. The activity of HGF was specifically blocked in SC CM reducing sprout length compared to control CM. In contrast, MVF sprout number did not differ between control or HGF-deficient SC CM media. Next, we cultured MVF in the presence of CM from satellite cells exposed to normoxic (20% O2 ) or hypoxic (1% O2 ) conditions. Hypoxic CM recapitulated a MVF angiogenic response identical to HGF deficient satellite cell CM. Hypoxic conditions increased satellite cell HIF-1α protein abundance and VEGF mRNA abundance but decreased HGF mRNA abundance compared to normoxic satellite cells. Consistent with reduced HGF gene expression, HGF promoter activity decreased during hypoxia. Taken together, this data indicates that hypoxic modulation of satellite cell-mediated angiogenesis involves a reduction in satellite cell HGF expression. © 2013 Wiley Periodicals, Inc.

  1. Effect of vitamin E levels on the cell-mediated immunity of broilers vaccinated against coccidiosis

    Directory of Open Access Journals (Sweden)

    ICM da Silva

    2011-03-01

    Full Text Available Studies on the relationships between animal nutrition and immunity have sought reliable methodologies to measure responses. Cell-mediated immune response is similarly studied in humans. The cutaneous basophil hypersensitivity test (CBH is one of the methods to measure that response and consists in the infiltration of inflammatory cells, particularly of lymphocytes and basophils, as result of the application of substances capable of inducing cell proliferation in determined sites, such as wings, wattle, and interdigital space in birds. CBH is considered a simple and fast method and can be applied in birds of different ages. In immunocompetence studies with poultry, phytohemagglutinin-P (PHA-P is a commonly used substance, despite the variability of the response related to the method of application (intradermal injection and the antigens used. In the present experiment, PHA-P was used to observe the cell-mediated immune response of 216 chicks fed three dietary levels of vitamin E from 1 to 36 days of age. All birds were immunologically challenged by vaccination against coccidiosis at three days of age and against Newcastle Disease (NCD at 14 and 30 days of age. At 36 days of age, birds were submitted to the CBH test according to the methodology of Corrier & DeLoach (1990. Birds fed 65mg/kg of vitamin E presented lasting cell reaction (p<0.08, which indicates that this vitamin E level improved cell immune response of birds due to its antioxidant and immunomodulating properties. The use of this vitamin E level can be considered by nutritionists under practical conditions, aiming to improve broiler immunity.

  2. Cytomegalovirus-Infected Cells Resist T Cell Mediated Killing in an HLA-Recognition Independent Manner.

    Science.gov (United States)

    Proff, Julia; Walterskirchen, Christian; Brey, Charlotte; Geyeregger, Rene; Full, Florian; Ensser, Armin; Lehner, Manfred; Holter, Wolfgang

    2016-01-01

    In order to explore the potential of HLA-independent T cell therapy for human cytomegalovirus (HCMV) infections, we developed a chimeric antigen receptor (CAR) directed against the HCMV encoded glycoprotein B (gB), which is expressed at high levels on the surface of infected cells. T cells engineered with this anti-gB CAR recognized HCMV-infected cells and released cytokines and cytotoxic granules. Unexpectedly, and in contrast to analogous approaches for HIV, Hepatitis B or Hepatitis C virus, we found that HCMV-infected cells were resistant to killing by the CAR-modified T cells. In order to elucidate whether this phenomenon was restricted to the use of CARs, we extended our experiments to T cell receptor (TCR)-mediated recognition of infected cells. To this end we infected fibroblasts with HCMV-strains deficient in viral inhibitors of antigenic peptide presentation and targeted these HLA-class I expressing peptide-loaded infected cells with peptide-specific cytotoxic T cells (CTLs). Despite strong degranulation and cytokine production by the T cells, we again found significant inhibition of lysis of HCMV-infected cells. Impairment of cell lysis became detectable 1 day after HCMV infection and gradually increased during the following 3 days. We thus postulate that viral anti-apoptotic factors, known to inhibit suicide of infected host cells, have evolved additional functions to directly abrogate T cell cytotoxicity. In line with this hypothesis, CAR-T cell cytotoxicity was strongly inhibited in non-infected fibroblasts by expression of the HCMV-protein UL37x1, and even more so by additional expression of UL36. Our data extend the current knowledge on Betaherpesviral evasion from T cell immunity and show for the first time that, beyond impaired antigen presentation, infected cells are efficiently protected by direct blockade of cytotoxic effector functions through viral proteins.

  3. Autophagy plays a critical role in ChLym-1-induced cytotoxicity of non-hodgkin's lymphoma cells.

    Directory of Open Access Journals (Sweden)

    Jiajun Fan

    Full Text Available Autophagy is a critical mechanism in both cancer therapy resistance and tumor suppression. Monoclonal antibodies have been documented to kill tumor cells via apoptosis, antibody-dependent cellular cytotoxicity (ADCC and complement-dependent cytotoxicity (CDC. In this study, we report for the first time that chLym-1, a chimeric anti-human HLA-DR monoclonal antibody, induces autophagy in Raji Non-Hodgkin's Lymphoma (NHL cells. Interestingly, inhibition of autophagy by pharmacological inhibitors (3-methyladenine and NH4Cl or genetic approaches (siRNA targeting Atg5 suppresses chLym-1-induced growth inhibition, apoptosis, ADCC and CDC in Raji cells, while induction of autophagy could accelerate cytotoxic effects of chLym-1 on Raji cells. Furthermore, chLym-1-induced autophagy can mediate apoptosis through Caspase 9 activation, demonstrating the tumor-suppressing role of autophagy in antilymphoma effects of chLym-1. Moreover, chLym-1 can activate several upstream signaling pathways of autophagy including Akt/mTOR and extracellular signal-regulated kinase 1/2 (Erk1/2. These results elucidate the critical role of autophagy in cytotoxicity of chLym-1 antibody and suggest a potential therapeutic strategy of NHL therapy by monoclonal antibody chLym-1 in combination with autophagy inducer.

  4. Remarkable heterogeneity displayed by oval cells in rat and mouse models of stem cell-mediated liver regeneration

    DEFF Research Database (Denmark)

    Jelnes, Peter; Santoni-Rugiu, Eric; Rasmussen, Morten

    2007-01-01

    the molecular phenotypes of oval cells in several of the most commonly used protocols of stem cell-mediated liver regeneration-namely, treatment with 2-acetylaminofluorene and partial (70%) hepatectomy (AAF/PHx); a choline-deficient, ethionine-supplemented (CDE) diet; a 3,5-diethoxycarbonyl-1,4-dihydro...

  5. CELL-MEDIATED IMMUNE RESPONSES IN THE SEA-STAR ASTERIAS RUBENS (ECHINODERM)

    OpenAIRE

    Michel Leclerc

    2012-01-01

    Cell-mediated immune responses occur in sea star system. In Asterias rubens it is said that B sea star lymphocytes and T sea star lymphocytes exist in the axial organ which can be considered as an ancestral lymphoid organ. In the same manner the origin of lymphocytes can be found in Invertebrates such as Echinodermal.

  6. Effect of renal and non-renal ischemia/reperfusion on cell-mediated immunity in organs and plasma

    DEFF Research Database (Denmark)

    Brøchner, Anne C; Dagnaes-Hansen, Frederik; Toft, Palle

    2010-01-01

    , the mortality rate still remains above 50%. The causes of death are primarily extra-renal and include infection, shock, septicemia, and respiratory failure. We wanted to evaluate the cell-mediated inflammatory response of renal ischemia-reperfusion (I/R) and non-renal I/R, in blood and in distant organs. In our...

  7. Membrane-bound Dickkopf-1 in Foxp3+ regulatory T cells suppresses T-cell-mediated autoimmune colitis.

    Science.gov (United States)

    Chae, Wook-Jin; Park, Jong-Hyun; Henegariu, Octavian; Yilmaz, Saliha; Hao, Liming; Bothwell, Alfred L M

    2017-10-01

    Induction of tolerance is a key mechanism to maintain or to restore immunological homeostasis. Here we show that Foxp3 + regulatory T (Treg) cells use Dickkopf-1 (DKK-1) to regulate T-cell-mediated tolerance in the T-cell-mediated autoimmune colitis model. Treg cells from DKK-1 hypomorphic doubleridge mice failed to control CD4 + T-cell proliferation, resulting in CD4 T-cell-mediated autoimmune colitis. Thymus-derived Treg cells showed a robust expression of DKK-1 but not in naive or effector CD4 T cells. DKK-1 expression in Foxp3 + Treg cells was further increased upon T-cell receptor stimulation in vitro and in vivo. Interestingly, Foxp3 + Treg cells expressed DKK-1 in the cell membrane and the functional inhibition of DKK-1 using DKK-1 monoclonal antibody abrogated the suppressor function of Foxp3 + Treg cells. DKK-1 expression was dependent on de novo protein synthesis and regulated by the mitogen-activated protein kinase pathway but not by the canonical Wnt pathway. Taken together, our results highlight membrane-bound DKK-1 as a novel Treg-derived mediator to maintain immunological tolerance in T-cell-mediated autoimmune colitis. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

  8. Effect of response to backtest and housing condition on cell-mediated and humoral immunity in adult pigs

    NARCIS (Netherlands)

    Geverink, N.A.; Parmentier, H.K.; Vries Reilingh, de G.; Schouten, W.G.P.; Gort, G.; Wiegant, V.M.

    2004-01-01

    Several recent studies in juvenile pigs demonstrated a relationship between the degree of resistance displayed early in life in a so-called "backtest" and parameters of cell-mediated and humoral immunity. Some of the immune characteristics were reported to depend on the interaction between backtest

  9. Evidence of functional cell-mediated immune responses to nontypeable Haemophilus influenzae in otitis-prone children

    Science.gov (United States)

    Seppanen, Elke; Tan, Dino; Corscadden, Karli J.; Currie, Andrew J.; Richmond, Peter C.; Thornton, Ruth B.

    2018-01-01

    Otitis media (OM) remains a common paediatric disease, despite advances in vaccinology. Susceptibility to recurrent acute OM (rAOM) has been postulated to involve defective cell-mediated immune responses to common otopathogenic bacteria. We compared the composition of peripheral blood mononuclear cells (PBMC) from 20 children with a history of rAOM (otitis-prone) and 20 healthy non-otitis-prone controls, and assessed innate and cell-mediated immune responses to the major otopathogen nontypeable Haemophilus influenzae (NTHi). NTHi was a potent stimulator of inflammatory cytokine secretion from PBMC within 4 hours, with no difference in cytokine levels produced between PBMC from cases or controls. In the absence of antigen stimulation, otitis-prone children had more circulating Natural Killer (NK) cells (potitis-prone and non-otitis-prone children (potitis-prone children are functional and respond to NTHi. CD8+ T cells and NK cells from both cases and controls produced IFNγ in response to polyclonal stimulus (Staphylococcal enterotoxin B; SEB), with more IFNγ+ CD8+ T cells present in cases than controls (pOtitis-prone children had more circulating IFNγ-producing NK cells (potitis-prone children mounted innate and T cell-mediated responses to NTHi challenge that were comparable to healthy children. These data provide evidence that otitis-prone children do not have impaired functional cell mediated immunity. PMID:29621281

  10. A 17 year experience in perioperative anaphylaxis 1998-2015: harmonising optimal detection of mast cell mediator release.

    OpenAIRE

    Egner, W.; Sargur, R.; Shrimpton, A.; York, M.; Green, K.

    2016-01-01

    BACKGROUND: Sheffield NARCOS (National Adverse Reactions Advisory Service) investigates suspected perioperative anaesthetic reactions using serial tryptase, urinary methylhistamine and clinical information. Further recommendations for additional allergy clinic assessment are provided. OBJECTIVE: To establish a robustly measurable protocol for identifying mast cell mediator (MMR) release in this cohort. To compare these thresholds with previous suggested thresholds and algorithms. METHOD: A re...

  11. Gold Nanoparticles Cytotoxicity

    Science.gov (United States)

    Mironava, Tatsiana

    Over the last two decades gold nanoparticles (AuNPs) have been used for many scientific applications and have attracted attention due to the specific chemical, electronic and optical size dependent properties that make them very promising agents in many fields such as medicine, imagine techniques and electronics. More specifically, biocompatible gold nanoparticles have a huge potential for use as the contrast augmentation agent in X-ray Computed Tomography and Photo Acoustic Tomography for early tumor diagnostic as well these nanoparticles are extensively researched for enhancing the targeted cancer treatment effectiveness such as photo-thermal and radiotherapy. In most biomedical applications biocompatible gold nanoparticles are labeled with specific tumor or other pathology targeting antibodies and used for site specific drug delivery. However, even though gold nanoparticles poses very high level of anti cancer properties, the question of their cytotoxicity ones they are released in normal tissue has to be researched. Moreover, the huge amount of industrially produced gold nanoparticles raises the question of these particles being a health hazard, since the penetration is fairly easy for the "nano" size substances. This study focuses on the effect of AuNPs on a human skin tissue, since it is fall in both categories -- the side effects for biomedical applications and industrial workers and users' exposure during production and handling. Therefore, in the present project, gold nanoparticles stabilized with the biocompatible agent citric acid were generated and characterized by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). The cytotoxic effect of AuNPs release to healthy skin tissue was modeled on 3 different cell types: human keratinocytes, human dermal fibroblasts, and human adipose derived stromal (ADS) cells. The AuNPs localization inside the cell was found to be cell type dependent. Overall cytotoxicity was found to be dependent

  12. Cytotoxic constituents of Bursera permollis.

    Science.gov (United States)

    Wickramaratne, D B; Mar, W; Chai, H; Castillo, J J; Farnsworth, N R; Soejarto, D D; Cordell, G A; Pezzuto, J M; Kinghorn, A D

    1995-02-01

    Four cytotoxic lignans were isolated from the stem bark of Bursera permollis (Burseraceae), namely, deoxypodophyllotoxin (1), beta-peltatin methyl ether (2), picro-beta-peltatin methyl ether (3), and dehydro-beta-peltatin methyl ether (4). Also isolated was the inactive lignan, nemerosin (5). Compounds 1 and 2 were potently cytotoxic when evaluated against a panel of human cancer cell lines.

  13. Cell-mediated immune suppression effect of rocket kerosene through dermal exposure in mice

    Directory of Open Access Journals (Sweden)

    Bing-xin XU

    2015-10-01

    Full Text Available Objective To study the effect of cell-mediated immune suppression effect of rocket kerosene (RK through dermal application in mice. Methods Skin delayed type hypersensitivity (DTH was used to observe the relation of the RK amount the skin exposed and the cellular immune inhibitory function. Different amount of the undiluted fuel was smeared directly onto the dorsal skin of mice. Mice in negative and positive control groups were treated with acetone. After the last exposure, all the mice except those in negative control group were allergized by evenly smearing with 1% dinitrofluorobenzene (DNFB solution on their dorsum. Five days after allergy, 1% DNFB solution was smeared onto right ear of all mice to stimulate the allergic reaction. Twenty-four hours after attack, the auricle swelling, spleen index and thymus index in corresponding mice were determined. In the first series of experiments, different dosages of RK were applied once, and the ICR mice were randomly divided into negative control group, positive control group and experimental group (0.5ml/kg.BW×1, 1ml/kg.BW×1 and 2ml/kg.BW×1 group. In the second series of experiments, the certain and same dosage of RK was applied for different times, and the ICR mice were randomly divided into negative control group, positive control group and experimental group (0.5ml/kg.BW×1, 0.5mL/kg.BW×2, 0.5ml/kg.BW×3, 0.5ml/kg.BW×4 and 0.5mL/kg.BW×5 group. In the third series of experiments, the different dosages of RK were applied more than once, and the ICR mice were randomly divided into negative control group, positive control group and experimental group (0.5ml/kg.BW×5, 1ml/kg.BW×5 and 2ml/kg.BW×5 group. Lymphocyte proliferation experiment in vitrowas conducted to observe the persistent time of the cell-mediated immune suppression in mice by RK dermal exposure. The lymphocyte proliferation induced by concanavalin A (Con A was analyzed by MTT assay, and T lymphocyte subsets (CD3+, CD4+ and CD

  14. Glycosylation regulates NK cell-mediated effector function through PI3K pathway

    Czech Academy of Sciences Publication Activity Database

    Benson, Veronika; Grobárová, Valeria; Richter, Jan; Fišerová, Anna

    2010-01-01

    Roč. 22, č. 3 (2010), s. 167-177 ISSN 0953-8178 R&D Projects: GA AV ČR IAA500200620; GA AV ČR IAA500200509; GA ČR GA204/06/0771; GA ČR GD310/08/H077 Institutional research plan: CEZ:AV0Z50200510 Keywords : cytotoxic activity * gene regulation * glycoconjugate Subject RIV: EC - Immunology Impact factor: 3.301, year: 2010

  15. [Optimization of triple plasmids transfection into HEK293 cells mediated by polyethylenimine].

    Science.gov (United States)

    Fu, Qiang; Li, Yan; Zheng, Zhaofen; Liu, Aizhong; Yuan, Zhenhua; Peng, Jianqiang; He, Jin

    2015-02-01

    In the present study, packaging system composed of pAAV-CMV-GFP, pAAV-RC and pHelper were transfected into human embryonic kidney 293 cells (HEK293 cells) mediated by polyethyleneimine (PEI) to explore an optimal transfection condition. Different total plasmid DNA dosages (1, 2, 3, 4, 5, 6 μg) and different PEI/Plasmid ratios (1:1, 3:1, 5:1, 7:1) were tested with detection of green fluorescence protein (GFP) with ImagePro Plus6. 0 Software. Then transfection efficiency of the optimized transfection system was further observed for different time periods(12, 24, 36, 48, 60, 72 h). The results showed that total plasmid dosage of 4 μg/well with PEI/plasmid ratio of 3 : 1-5 : 1 was an efficient transfection condition. Transfection efficiency-time curve was an S-shaped curve. Transfection efficiency reached a plateau at 60 h after transfection. The optimized conditions for PEI-mediated transfection at the optimal time result in enhanced transfection efficiency of triple plasmid into HEK293 cells.

  16. TRESK channel as a potential target to treat T-cell mediated immune dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jaehee [Medical Research Center for Neural Dysfunction, Department of Physiology, Institute of Health Sciences, Gyeongsang National University, School of Medicine, Jinju 660-751 (Korea, Republic of); Kang, Dawon, E-mail: dawon@gnu.ac.kr [Medical Research Center for Neural Dysfunction, Department of Physiology, Institute of Health Sciences, Gyeongsang National University, School of Medicine, Jinju 660-751 (Korea, Republic of)

    2009-12-25

    In this review, we propose that TRESK background K{sup +} channel could serve as a potential therapeutic target for T-cell mediated immune dysfunction. TRESK has many immune function-related properties. TRESK is abundantly expressed in the thymus, the spleen, and human leukemic T-lymphocytes. TRESK is highly activated by Ca{sup 2+}, calcineurin, acetylcholine, and histamine which induce hypertrophy, whereas TRESK is inhibited by immunosuppressants, such as cyclosporin A and FK506. Cyclosporine A and FK506 target the binding site of nuclear factor of activated T-cells (NFAT) to inhibit calcineurin. Interestingly, TRESK possesses an NFAT-like docking site that is present at its intracellular loop. Calcineurin has been found to interact with TRESK via specific NFAT-like docking site. When the T-cell is activated, calcineurin can bind to the NFAT-docking site of TRESK. The activation of both TRESK and NFAT via Ca{sup 2+}-calcineurin-NFAT/TRESK pathway could modulate the transcription of new genes in addition to regulating several aspects of T-cell function.

  17. First line of defense: Innate cell-mediated control of pulmonary Aspergillosis

    Directory of Open Access Journals (Sweden)

    Vanessa eEspinosa

    2016-03-01

    Full Text Available Mycotic infections and their effect on the human condition have been widely overlooked and poorly surveilled by many health organizations even though mortality rates have increased in recent years. The increased usage of immunosuppressive and myeloablative therapies for the treatment of malignant as well as non-malignant diseases has contributed significantly to the increased incidence of fungal infections. Invasive fungal infections have been found to be responsible for at least 1.5 million deaths worldwide. About 90% of these deaths can be attributed to Cryptococcus, Candida, Aspergillus, and Pneumocystis. A better understanding of how the host immune system contains fungal infection is likely to facilitate the development of much needed novel antifungal therapies. Innate cells are responsible for the rapid recognition and containment of fungal infections and have been found to play essential roles in defense against multiple fungal pathogens. In this review we summarize our current understanding of host-fungi interactions with a focus on mechanisms of innate cell-mediated recognition and control of pulmonary aspergillosis.

  18. Atrophying pityriasis versicolor as an idiosyncratic T cell-mediated response to Malassezia: A case series.

    Science.gov (United States)

    Levy, Jonathan Michael Stephen; Magro, Cynthia

    2017-04-01

    Atrophying pityriasis versicolor (PV), first described in 1971, is a rare variant in which lesions appear atrophic. We sought to determine the pathophysiology of atrophying PV. A retrospective chart review identified 6 cases of atrophying PV. In all cases, routine light microscopy, an elastic tissue stain, and immunohistochemical assessment for the expression of CD3, CD4, CD8, GATA3 and CXCR3 was performed. All cases demonstrated hyperkeratosis with intracorneal infiltration by pathogenic hyphal forms as well as epidermal attenuation and papillary dermal elastolysis. A supervening, mild-to-moderate, superficial lymphocytic infiltrate was noted and characterized by a focal CD8 + T cell-mediated interface dermatitis along with a mixed T-cell infiltrate composed of GATA3 + and CXCR3 + T cells. Small sample size and the loss of some patients to follow-up. Atrophying PV represents the sequelae of a mixed helper T-cell (T H 1 and T H 2) idiosyncratic immune response to Malassezia and can present as a protracted dermatosis that may clinically mimic an atypical lymphocytic infiltrate. T H 1 cytokines can recruit histiocytes, a source of elastases, and upregulate matrix metalloproteinase activity, which may contribute to epidermal atrophy. Copyright © 2016. Published by Elsevier Inc.

  19. Epistasis between MicroRNAs 155 and 146a during T Cell-Mediated Antitumor Immunity

    Directory of Open Access Journals (Sweden)

    Thomas B. Huffaker

    2012-12-01

    Full Text Available An increased understanding of antitumor immunity is necessary for improving cell-based immunotherapies against human cancers. Here, we investigated the roles of two immune system-expressed microRNAs (miRNAs, miR-155 and miR-146a, in the regulation of antitumor immune responses. Our results indicate that miR-155 promotes and miR-146a inhibits interferon γ (IFNγ responses by T cells and reduces solid tumor growth in vivo. Using a double-knockout (DKO mouse strain deficient in both miR-155 and miR-146a, we have also identified an epistatic relationship between these two miRNAs. DKO mice had defective T cell responses and tumor growth phenotypes similar to miR-155−/− mice. Further analysis of the T cell compartment revealed that miR-155 modulates IFNγ expression through a mechanism involving repression of Ship1. Our work reveals critical roles for miRNAs in the reciprocal regulation of CD4+ and CD8+ T cell-mediated antitumor immunity and demonstrates the dominant nature of miR-155 during its promotion of immune responses.

  20. Dynamics of an HIV-1 infection model with cell mediated immunity

    Science.gov (United States)

    Yu, Pei; Huang, Jianing; Jiang, Jiao

    2014-10-01

    In this paper, we study the dynamics of an improved mathematical model on HIV-1 virus with cell mediated immunity. This new 5-dimensional model is based on the combination of a basic 3-dimensional HIV-1 model and a 4-dimensional immunity response model, which more realistically describes dynamics between the uninfected cells, infected cells, virus, the CTL response cells and CTL effector cells. Our 5-dimensional model may be reduced to the 4-dimensional model by applying a quasi-steady state assumption on the variable of virus. However, it is shown in this paper that virus is necessary to be involved in the modeling, and that a quasi-steady state assumption should be applied carefully, which may miss some important dynamical behavior of the system. Detailed bifurcation analysis is given to show that the system has three equilibrium solutions, namely the infection-free equilibrium, the infectious equilibrium without CTL, and the infectious equilibrium with CTL, and a series of bifurcations including two transcritical bifurcations and one or two possible Hopf bifurcations occur from these three equilibria as the basic reproduction number is varied. The mathematical methods applied in this paper include characteristic equations, Routh-Hurwitz condition, fluctuation lemma, Lyapunov function and computation of normal forms. Numerical simulation is also presented to demonstrate the applicability of the theoretical predictions.

  1. Loss of STAT3 in Lymphoma Relaxes NK Cell-Mediated Tumor Surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Putz, Eva Maria [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Hoelzl, Maria Agnes [Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna (MUV), Waehringer Strasse 13A, Vienna 1090 (Austria); Baeck, Julia [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Bago-Horvath, Zsuzsanna [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Clinical Institute of Pathology, Medical University of Vienna (MUV), Waehringer Gürtel 18-20, Vienna 1090 (Austria); Schuster, Christian [Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna (MUV), Waehringer Strasse 13A, Vienna 1090 (Austria); Reichholf, Brian [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Kern, Daniela; Aberger, Fritz [Department of Molecular Biology, University of Salzburg, Hellbrunnerstrasse 34, Salzburg 5020 (Austria); Sexl, Veronika; Hoelbl-Kovacic, Andrea, E-mail: andrea.hoelbl@vetmeduni.ac.at [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria)

    2014-01-27

    The transcription factors and proto-oncogenes STAT3 and STAT5 are highly activated in hematological malignancies and represent promising therapeutic targets. Whereas the importance of STAT5 as tumor promoter is beyond doubt, the role of STAT3 in hematological cancers is less well understood. Both, enforced as well as attenuated expression of STAT3 were reported in hematopoietic malignancies. Recent evidence implicates STAT3 as key player for tumor immune surveillance as it both mediates the production of and response to inflammatory cytokines. Here we investigated the effects of STAT3 deletion in a BCR/ABL-induced lymphoma model, which is tightly controlled by natural killer (NK) cells in vivo. Upon STAT3 deletion tumor growth is significantly enhanced when compared to STAT3-expressing controls. The increased tumor size upon loss of STAT3 was accompanied by reduced NK cell infiltration and decreased levels of the cytokine IFN-γ and the chemokine RANTES. Upon transplantation into NK cell-deficient mice differences in lymphoma size were abolished indicating that STAT3 expression in the tumor cells controls NK cell-dependent tumor surveillance. Our findings indicate that STAT3 inhibition in lymphoma patients will impair NK cell-mediated tumor surveillance, which needs to be taken into account when testing STAT3 inhibitors in preclinical or clinical trials.

  2. Fibrocyte-like cells mediate acquired resistance to anti-angiogenic therapy with bevacizumab

    Science.gov (United States)

    Mitsuhashi, Atsushi; Goto, Hisatsugu; Saijo, Atsuro; Trung, Van The; Aono, Yoshinori; Ogino, Hirokazu; Kuramoto, Takuya; Tabata, Sho; Uehara, Hisanori; Izumi, Keisuke; Yoshida, Mitsuteru; Kobayashi, Hiroaki; Takahashi, Hidefusa; Gotoh, Masashi; Kakiuchi, Soji; Hanibuchi, Masaki; Yano, Seiji; Yokomise, Hiroyasu; Sakiyama, Shoji; Nishioka, Yasuhiko

    2015-01-01

    Bevacizumab exerts anti-angiogenic effects in cancer patients by inhibiting vascular endothelial growth factor (VEGF). However, its use is still limited due to the development of resistance to the treatment. Such resistance can be regulated by various factors, although the underlying mechanisms remain incompletely understood. Here we show that bone marrow-derived fibrocyte-like cells, defined as alpha-1 type I collagen-positive and CXCR4-positive cells, contribute to the acquired resistance to bevacizumab. In mouse models of malignant pleural mesothelioma and lung cancer, fibrocyte-like cells mediate the resistance to bevacizumab as the main producer of fibroblast growth factor 2. In clinical specimens of lung cancer, the number of fibrocyte-like cells is significantly increased in bevacizumab-treated tumours, and correlates with the number of treatment cycles, as well as CD31-positive vessels. Our results identify fibrocyte-like cells as a promising cell biomarker and a potential therapeutic target to overcome resistance to anti-VEGF therapy. PMID:26635184

  3. Bowman Capsulitis Predicts Poor Kidney Allograft Outcome in T Cell-Mediated Rejection.

    Science.gov (United States)

    Gallan, Alexander J; Chon, W James; Josephson, Michelle A; Cunningham, Patrick N; Henriksen, Kammi J; Chang, Anthony

    2018-02-28

    Acute T cell-mediated rejection (TCMR) is an important cause of renal allograft loss. The Banff classification for tubulointerstitial (type I) rejection is based on the extent of both interstitial inflammation and tubulitis. Lymphocytes may also be present between parietal epithelial cells and Bowman capsules in this setting, which we have termed "capsulitis." We conducted this study to determine the clinical significance of capsulitis. We identified 42 patients from the pathology archives at the University of Chicago with isolated Banff type I TCMR from 2010-2015. Patient demographic data, Banff classification, and graft outcome measurements were compared between capsulitis and non-capsulitis groups using Mann-Whitney U test. Capsulitis was present in 26 (62%), and was more frequently seen in Banff IB than IA TCMR (88% vs 44%, P=.01). Patients with capsulitis had a higher serum creatinine at biopsy (4.6 vs 2.9mg/dL, P=.04) and were more likely to progress to dialysis (42% vs 13%, P=.06) with fewer recovering their baseline serum creatinine (12% vs 38%, P=.08). Patients with both Banff IA TCMR and capsulitis have clinical outcomes similar or possibly worse than Banff IB TCMR compared to those with Banff IA and an absence of capsulitis. Capsulitis is an important pathologic parameter in the evaluation of kidney transplant biopsies with potential diagnostic, prognostic, and therapeutic implications in the setting of TCMR. Copyright © 2018. Published by Elsevier Inc.

  4. Epstein-Barr virus reactivation associated with diminished cell-mediated immunity in antarctic expeditioners

    Science.gov (United States)

    Mehta, S. K.; Pierson, D. L.; Cooley, H.; Dubow, R.; Lugg, D.

    2000-01-01

    Epstein-Barr virus (EBV) reactivation and cell-mediated immune (CMI) responses were followed in 16 Antarctic expeditioners during winter-over isolation at 2 Australian National Antarctic Research Expedition stations. Delayed-type hypersensitivity (DTH) skin testing was used as an indicator of the CMI response, that was evaluated 2 times before winter isolation and 3 times during isolation. At all 5 evaluation times, 8 or more of the 16 subjects had a diminished CMI response. Diminished DTH was observed on every test occasion in 4/16 subjects; only 2/16 subjects exhibited normal DTH responses for all 5 tests. A polymerase chain reaction (PCR) assay was used to detect EBV DNA in saliva specimens collected before, during, and after the winter isolation. EBV DNA was present in 17% (111/642) of the saliva specimens; all 16 subjects shed EBV in their saliva on at least 1 occasion. The probability of EBV shedding increased (P = 0.013) from 6% before or after winter isolation to 13% during the winter period. EBV appeared in saliva during the winter isolation more frequently (P viruses.

  5. Maternal immunity enhances Mycoplasma hyopneumoniae vaccination induced cell-mediated immune responses in piglets.

    Science.gov (United States)

    Bandrick, Meggan; Theis, Kara; Molitor, Thomas W

    2014-06-05

    Passively acquired maternal derived immunity (MDI) is a double-edged sword. Maternal derived antibody-mediated immunity (AMI) and cell-mediated immunity (CMI) are critical immediate defenses for the neonate; however, MDI may interfere with the induction of active immunity in the neonate, i.e. passive interference. The effect of antigen-specific MDI on vaccine-induced AMI and CMI responses to Mycoplasma hyopneumoniae (M. hyopneumoniae) was assessed in neonatal piglets. To determine whether CMI and AMI responses could be induced in piglets with MDI, piglets with high and low levels of maternal M. hyopneumoniae-specific immunity were vaccinated against M. hyopneumoniae at 7 d of age. Piglet M. hyopneumoniae-specific antibody, lymphoproliferation, and delayed type hypersensitivity (DTH) responses were measured 7 d and 14 d post vaccination. Piglets with M. hyopneumoniae-specific MDI failed to show vaccine-induced AMI responses; there was no rise in M. hyopneumoniae antibody levels following vaccination of piglets in the presence of M. hyopneumoniae-specific MDI. However, piglets with M. hyopneumoniae-specific MDI had primary (antigen-specific lymphoproliferation) and secondary (DTH) M. hyopneumoniae-specific CMI responses following vaccination. In this study neonatal M. hyopneumoniae-specific CMI was not subject to passive interference by MDI. Further, it appears that both maternal derived and endogenous CMI contribute to M. hyopneumoniae-specific CMI responses in piglets vaccinated in the face of MDI.

  6. Cell-mediated retraction versus hemodynamic loading - A delicate balance in tissue-engineered heart valves.

    Science.gov (United States)

    van Loosdregt, Inge A E W; Argento, Giulia; Driessen-Mol, Anita; Oomens, Cees W J; Baaijens, Frank P T

    2014-06-27

    Preclinical studies of tissue-engineered heart valves (TEHVs) showed retraction of the heart valve leaflets as major failure of function mechanism. This retraction is caused by both passive and active cell stress and passive matrix stress. Cell-mediated retraction induces leaflet shortening that may be counteracted by the hemodynamic loading of the leaflets during diastole. To get insight into this stress balance, the amount and duration of stress generation in engineered heart valve tissue and the stress imposed by physiological hemodynamic loading are quantified via an experimental and a computational approach, respectively. Stress generation by cells was measured using an earlier described in vitro model system, mimicking the culture process of TEHVs. The stress imposed by the blood pressure during diastole on a valve leaflet was determined using finite element modeling. Results show that for both pulmonary and systemic pressure, the stress imposed on the TEHV leaflets is comparable to the stress generated in the leaflets. As the stresses are of similar magnitude, it is likely that the imposed stress cannot counteract the generated stress, in particular when taking into account that hemodynamic loading is only imposed during diastole. This study provides a rational explanation for the retraction found in preclinical studies of TEHVs and represents an important step towards understanding the retraction process seen in TEHVs by a combined experimental and computational approach. © 2013 Published by Elsevier Ltd.

  7. Growth suppression of Leydig TM3 cells mediated by aryl hydrocarbon receptor

    International Nuclear Information System (INIS)

    Iseki, Minoru; Ikuta, Togo; Kobayashi, Tetsuya; Kawajiri, Kaname

    2005-01-01

    Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin induces developmental toxicity in reproductive organs. To elucidate the function of AhR, we generated stable transformants of TM3 cells overexpressing wild-type aryl hydrocarbon receptor (AhR) or its mutants which carried mutations in nuclear localization signal or nuclear export signal. In the presence of 3-methylcholanthrene (MC), proliferation of the cells transfected with wild-type AhR was completely suppressed, whereas cells expressing AhR mutants proliferated in a manner equivalent to control TM3 cells, suggesting AhR-dependent growth inhibition. The suppression was associated with up-regulation of cyclin-dependent kinase inhibitor p21 Cip1 , which was abolished by pretreatment with actinomycin D. A p38 MAPK specific inhibitor, SB203580, blocked the increase of p21 Cip1 mRNA in response to MC. Treatment with indigo, another AhR ligand, failed to increase of p21 Cip1 mRNA, although up-regulation of mRNA for CYP1A1 was observed. These data suggest AhR in Leydig cells mediates growth inhibition by inducing p21 Cip1

  8. Mathematical modeling on T-cell mediated adaptive immunity in primary dengue infections.

    Science.gov (United States)

    Sasmal, Sourav Kumar; Dong, Yueping; Takeuchi, Yasuhiro

    2017-09-21

    At present, dengue is the most common mosquito-borne viral disease in the world, and the global dengue incidence is increasing day by day due to climate changing. Here, we present a mathematical model of dengue viruses (DENVs) dynamics in micro-environment (cellular level) consisting of healthy cells, infected cells, virus particles and T-cell mediated adaptive immunity. We have considered the explicit role of cytokines and antibody in our model. We find that the virus load goes down to zero within 6 days as it is common for DENV infection. From our analysis, we have identified the important model parameters and done the numerical simulation with respect to such important parameters. We have shown that the cytokine mediated virus clearance plays a very important role in dengue dynamics. It can change the dynamical behavior of the system and causes essential extinction of the virus. Finally, we have incorporated the antiviral treatment for dengue in our model and shown that the basic reproduction number is directly proportional to the antiviral treatment effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Induction of cell-mediated immunity during early stages of infection with intracellular protozoa

    Directory of Open Access Journals (Sweden)

    Gazzinelli R.T.

    1998-01-01

    Full Text Available Toxoplasma gondii and Trypanosoma cruzi are intracellular parasites which, as part of their life cycle, induce a potent cell-mediated immunity (CMI maintained by Th1 lymphocytes and IFN-g. In both cases, induction of a strong CMI is thought to protect the host against rapid parasite multiplication and consequent pathology and lethality during the acute phase of infection. However, the parasitic infection is not eliminated by the immune system and the vertebrate host serves as a parasite reservoir. In contrast, Leishmania sp, which is a slow growing parasite, appears to evade induction of CMI during early stages of infection as a strategy for surviving in a hostile environment (i.e., inside the macrophages which are their obligatory niche in the vertebrate host. Recent reports show that the initiation of IL-12 synthesis by macrophages during these parasitic infections is a key event in regulating CMI and disease outcome. The studies reviewed here indicate that activation/inhibition of distinct signaling pathways and certain macrophage functions by intracellular protozoa are important events in inducing/modulating the immune response of their vertebrate hosts, allowing parasite and host survival and therefore maintaining parasite life cycles.

  10. 5-Azacytidine treatment sensitizes tumor cells to T-cell mediated cytotoxicity and modulates NK cells in patients with myeloid malignancies

    DEFF Research Database (Denmark)

    Gang, A O; Frøsig, T M; Brimnes, M K

    2014-01-01

    Treatment with the demethylating agent 5-Azacytidine leads to prolonged survival for patients with myelodysplastic syndrome, and the demethylation induces upregulation of cancer-testis antigens. Cancer-testis antigens are well-known targets for immune recognition in cancer, and the immune system ...

  11. Split anergized natural killer cells halt inflammation by inducing stem cell differentiation, resistance to NK cell cytotoxicity and prevention of cytokine and chemokine secretion

    Science.gov (United States)

    Tseng, Han-Ching; Cacalano, Nicholas; Jewett, Anahid

    2015-01-01

    The mechanism of suppression of NK cytotoxicity in cancer patients is not clearly established. In this paper we provide evidence that anergized NK cells induce differentiation of healthy Dental Pulp Stem Cells (DPSCs) or transformed Oral Squamous Cancer Stem Cells (OSCSCs) resulting in cell growth inhibition, resistance to NK cell-mediated cytotoxicity and prevention of inflammatory mediators secretion. Induction of cytotoxicity resistance in differentiated cells correlated with increased CD54 and MHC class I surface expression and mediated by the combination of IFN-γ and TNF-α since antibodies to both, but not each cytokine alone, was able to inhibit resistance. In contrast, inhibition of cytokine and chemokine release was mediated by IFN-γ since the addition of anti-IFN-γ antibody, and not anti-TNF-α, restored secretion of inflammatory mediators in NK cell cultures with differentiated DPSCs and OSCSCs. There was a gradual and time dependent decrease in MHC class I and CD54 expression which correlated with the restoration of NK cell cytotoxicity, augmentation of cytokine secretion and increased cell growth from days 0–12 post NK removal. Continuous presence of NK cells is required for the maintenance of cell differentiation since the removal of NK cell-mediated function reverses the phenotype and function of differentiated cells to their stem-like cells. PMID:25860927

  12. 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.

  13. Cytotoxicity effects of alkoxy

    Directory of Open Access Journals (Sweden)

    Wan M. Khairul

    2017-05-01

    Full Text Available In this study, the effort was to design and synthesize five new members of alkoxy substituted thiourea derivatives (3a–3e featuring general formula of A-ArC(ONHC(SNHAr-D in which A represents the methoxy group and D as –OCnH2n+1 (alkoxyl group, where n = 6,7,8,9, and 10 have been successfully designed, prepared, characterized, and evaluated for anti-amoebic activities. They were spectroscopically characterized by 1H and 13C Nuclear Magnetic Resonance (NMR, Fourier Transform Infrared (FT-IR spectroscopy, and Ultraviolet–visible (UV–vis spectroscopy analysis. In turn, they were used to investigate the cytotoxicity effect on Acanthamoeba sp. at their IC50 values and membrane permeability. Compounds 3a and 3b revealed to have good activity towards Acanthamoeba sp. compared to other compounds of 3c, 3d, and 3e. The observation under fluorescence microscopy by AOPI (Acridine-orange/Propidium iodide staining indicated that treated amoeba cells by 3a–3e show loss of their membrane permeability.

  14. Cell-mediated immune responses differentiate infections with Brucella suis from Yersinia enterocolitica serotype O : 9 in pigs

    DEFF Research Database (Denmark)

    Riber, Ulla; Jungersen, Gregers

    2007-01-01

    with YeO:9 were all negative, except for solitary false positives in 3.7% of the samples from both the experimentally YeO:9 infected pigs and control pigs. Skin tests using the same commercial Brucella antigen confirmed the ability of cell-mediated immune responses to differentiate between the two...... of antibody responses it was hypothesized that cell-mediated immune responses to non-LPS antigens of the two bacteria can be used to separate immune responses to these two biologically very different infections. Following subclinical experimental infections with Brucella suis biovar 2, high interferon......-gamma (IFN-gamma) assay responses with a commercial Brucella melitensis antigen preparation (Brucellergene OCB) preceded the development of antibodies. High IFN-gamma responses in the seven B. suis inoculated pigs with serological evidence of infection were consistent throughout a 20-week postinoculation...

  15. Cytotoxicity of dentin bonding agents.

    Science.gov (United States)

    Cal, Ebru; Guneri, Pelin; Atay, Ayse; Cetintas, Vildan Bozok

    2014-01-01

    This study sought to evaluate the cytotoxicity of 5 dentin bonding agents (Admira Bond, Adper Single Bond Plus, Clearfil SE Bond, Clearfil S3 Bond, and Heliobond) by XTT assay using human gingival fibroblast cells. Samples of dentin bonding agents were prepared on a black 96-well microplate, and the cytotoxicity of each bonding material was measured every 24 hours for 7 days, then on Days 14, 21, and 28. One-way ANOVA and Bonferroni post hoc tests were used for statistical analyses. All 5 materials were evaluated as severely cytotoxic (P agents showed severe cytotoxicity with viability results exception of Adper Single Bond Plus, toxicity continued to Day 28 for all compounds. The utmost care must be considered during the clinical utilization of dentin bonding agents to keep them within the area of restoration and prevent their contact with adjacent tissues.

  16. Cytotoxicity of Hymenocallis expansa alkaloids.

    Science.gov (United States)

    Antoun, M D; Mendoza, N T; Ríos, Y R; Proctor, G R; Wickramaratne, D B; Pezzuto, J M; Kinghorn, A D

    1993-08-01

    From the bulbs and leaves of Hymenocallis expansa (Amaryllidaceae), three alkaloid constituents were identified: (+)-tazettine, (+)-hippeastrine, and (-)-haemanthidine. These alkaloids demonstrated significant cytotoxicity when tested against a panel of human and murine tumor cell lines.

  17. pH-evoked dural afferent signaling is mediated by ASIC3 and is sensitized by mast cell mediators.

    Science.gov (United States)

    Yan, Jin; Wei, Xiaomei; Bischoff, Christina; Edelmayer, Rebecca M; Dussor, Gregory

    2013-09-01

    Prior studies have shown that decreased meningeal pH activates dural afferents via opening of acid-sensing ion channels (ASICs), suggesting one pathophysiological mechanism for the generation of headaches. The studies described here further examined the ASIC subtype mediating pH-induced dural-afferent activation and examined whether sensitization influences pH responses. Given the potential importance of meningeal mast cells to headache, the goal of this study was to evaluate dural afferent responses to pH following sensitization with mast cell mediators. Cutaneous allodynia was measured in rats following stimulation of the dura with decreased pH alone or in combination with mast cell mediators. Trigeminal ganglion neurons retrogradely labeled from the dura were stained with an ASIC3 antibody using immunohistochemistry. Current and action potentials evoked by changes in pH alone or in combination with mast cell mediators were measured in retrogradely labeled dural afferents using patch-clamp electrophysiology. pH-sensitive dural afferents generated currents in response to the ASIC3 activator 2-guanidine-4-methylquinazoline (GMQ), approximately 80% of these neurons express ASIC3 protein, and pH-evoked behavioral responses were inhibited by the ASIC3 blocker APETx2. Following exposure to mast cell mediators, dural afferents exhibited increased pH-evoked excitability, and cutaneous allodynia was observed at higher pH than with pH stimuli alone. These data indicate that the predominant ASIC subtype responding to decreased meningeal pH is ASIC3. Additionally, they demonstrate that in the presence of inflammation, dural afferents respond to even smaller decreases in pH providing further support for the ability of small pH changes within the meninges to initiate afferent input leading to headache. © 2013 American Headache Society.

  18. Slp-76 is a critical determinant of NK cell-mediated recognition of missing-self targets

    OpenAIRE

    Lampe, Kristin; Endale, Mehari; Cashman, Siobhan; Fang, Hao; Mattner, Jochen; Hildeman, David; Hoebe, Kasper

    2015-01-01

    Absence of MHC class I expression is an important mechanism by which NK cells recognize a variety of target cells, yet the pathways underlying “missing-self” recognition, including the involvement of activating receptors, remain poorly understood. Using ENU mutagenesis in mice, we identified a germline mutant, designated Ace, with a marked defect in NK cell-mediated recognition and elimination of “missing-self” targets. The causative mutation was linked to chromosome 11 and identified as a mi...

  19. UTX demethylase activity is required for satellite cell-mediated muscle regeneration.

    Science.gov (United States)

    Faralli, Hervé; Wang, Chaochen; Nakka, Kiran; Benyoucef, Aissa; Sebastian, Soji; Zhuang, Lenan; Chu, Alphonse; Palii, Carmen G; Liu, Chengyu; Camellato, Brendan; Brand, Marjorie; Ge, Kai; Dilworth, F Jeffrey

    2016-04-01

    The X chromosome-encoded histone demethylase UTX (also known as KDM6A) mediates removal of repressive trimethylation of histone H3 lysine 27 (H3K27me3) to establish transcriptionally permissive chromatin. Loss of UTX in female mice is embryonic lethal. Unexpectedly, male UTX-null mice escape embryonic lethality due to expression of UTY, a paralog that lacks H3K27 demethylase activity, suggesting an enzyme-independent role for UTX in development and thereby challenging the need for active H3K27 demethylation in vivo. However, the requirement for active H3K27 demethylation in stem cell-mediated tissue regeneration remains untested. Here, we employed an inducible mouse KO that specifically ablates Utx in satellite cells (SCs) and demonstrated that active H3K27 demethylation is necessary for muscle regeneration. Loss of UTX in SCs blocked myofiber regeneration in both male and female mice. Furthermore, we demonstrated that UTX mediates muscle regeneration through its H3K27 demethylase activity, as loss of demethylase activity either by chemical inhibition or knock-in of demethylase-dead UTX resulted in defective muscle repair. Mechanistically, dissection of the muscle regenerative process revealed that the demethylase activity of UTX is required for expression of the transcription factor myogenin, which in turn drives differentiation of muscle progenitors. Thus, we have identified a critical role for the enzymatic activity of UTX in activating muscle-specific gene expression during myofiber regeneration and have revealed a physiological role for active H3K27 demethylation in vivo.

  20. Effect of Zinc on Humoral and Cell-Mediated Immunity of Broilers Vaccinated Against Coccidiosis

    Directory of Open Access Journals (Sweden)

    Milad Moazeni

    2013-09-01

    Full Text Available Background: The aim of the present study was the comparison of humoral and cell-mediated immunity in ‎broilers fed with different levels of zinc during a coccidiosis challenge.‎Methods: One hundred and forty-‎four one-day-old broiler chicks were used with three ‎dietary zinc ‎(40, 120 and 200 mg/kg. At 14 d of age, all birds were inoculated orally with 5×103 sporulated oocysts of E. Tenella. ‎At ‎2, 22, 32, 42 ‎days of age, the blood serums were tested for ‎antibody titer against‎ Newcas­tle disease vaccine, using ‎the standard HI test. On day 42 the sum of nitrite ‎and nitrate based on the reduction of nitrate ‎to nitrite by cadmium ‎and white blood cell count (WBC using a hemocytometer were measured.Results: At 42 d, levels of ‎120 and 200 mg significantly (P< 0.05 increased the antibody titer in compare with the control. The peak response of CBH was observed at the level of 200 mg Zn/kg diet. Also both level of 120 and 200 mg Zn/kg diet increased WBC count and sum of nitrite and nitrate‎ in serum compared with the control.Conclusion: The levels of 120 and 200 mg Zn/kg diet could be considered as a non-pharmacologic booster of immunity in broilers chicks infected with E. Tenella.

  1. Endogenous n-3 polyunsaturated fatty acids attenuate T cell-mediated hepatitis via autophagy activation

    Directory of Open Access Journals (Sweden)

    Yanli Li

    2016-09-01

    Full Text Available Omega-3 polyunsaturated fatty acids (n-3 PUFAs exert anti-inflammatory effects in several liver disorders, including cirrhosis, acute liver failure, and fatty liver disease. To date, little is known about their role in immune-mediated liver diseases. In this study, we used fat-1 transgenic mice rich in endogenous n-3 PUFAs to examine the role of n-3 PUFAs in immune-mediated liver injury. Concanavalin A (Con A was administered intravenously to wild-type (WT and fat-1 transgenic mice to induce T cell-mediated hepatitis. Reduced liver damage was shown in Con A-administrated fat-1 transgenic mice, as evidenced by decreased mortality, attenuated hepatic necrosis, lessened serum alanine aminotransferase (ALT activity, and inhibited production of pro-inflammatory cytokines (e.g. TNF-α, IL-6, IL-17A and IFN-γ. In vivo and in vitro studies demonstrated that n-3 PUFAs significantly inhibited the activation of hepatic T cells and the differentiation of Th1 cells after Con A challenge. Further studies showed that n-3 PUFAs markedly increased autophagy level in Con A-treated fat-1 T cells compared with the WT counterparts. Blocking hepatic autophagy activity with chloroquine diminished the differences in T cell activation and liver injury between Con A-injected WT and fat-1 transgenic mice. We conclude that n-3 PUFAs limit Con A-induced hepatitis via an autophagy-dependent mechanism, and could be exploited as a new therapeutic approach for autoimmune hepatitis.

  2. Emerging Targets for Developing T Cell-Mediated Vaccines for Human Immunodeficiency Virus (HIV-1

    Directory of Open Access Journals (Sweden)

    Danushka K. Wijesundara

    2017-10-01

    Full Text Available Human immunodeficiency virus (HIV-1 has infected >75 million individuals globally, and, according to the UN, is responsible for ~2.1 million new infections and 1.1 million deaths each year. Currently, there are ~37 million individuals with HIV infection and the epidemic has already resulted in 35 million deaths. Despite the advances of anti-retroviral therapy (ART, a cost-effective vaccine remains the best long-term solution to end the HIV-1 epidemic especially given that the vast majority of infected individuals live in poor socio-economic regions of the world such as Sub-Saharan Africa which limits their accessibility to ART. The modest efficacy of the RV144 Thai trial provides hope that a vaccine for HIV-1 is possible, but as markers for sterilizing immunity are unknown, the design of an effective vaccine is empirical, although broadly cross-reactive neutralizing antibodies (bNAb that can neutralize various quasispecies of HIV-1 are considered crucial. Since HIV-1 transmission often occurs at the genito-rectal mucosa and is cell-associated, there is a need to develop vaccines that can elicit CD8+ T cell immunity with the capacity to kill virus infected cells at the genito-rectal mucosa and the gut. Here we discuss the recent progress made in developing T cell-mediated vaccines for HIV-1 and emphasize the need to elicit mucosal tissue-resident memory CD8+ T (CD8+ Trm cells. CD8+ Trm cells will likely form a robust front-line defense against HIV-1 and eliminate transmitter/founder virus-infected cells which are responsible for propagating HIV-1 infections following transmission in vast majority of cases.

  3. Mixed Signals: Co-Stimulation in Invariant Natural Killer T Cell-Mediated Cancer Immunotherapy

    Directory of Open Access Journals (Sweden)

    Susannah C. Shissler

    2017-11-01

    Full Text Available Invariant natural killer T (iNKT cells are an integral component of the immune system and play an important role in antitumor immunity. Upon activation, iNKT cells can directly kill malignant cells as well as rapidly produce cytokines that stimulate other immune cells, making them a front line defense against tumorigenesis. Unfortunately, iNKT cell number and activity are reduced in multiple cancer types. This anergy is often associated with upregulation of co-inhibitory markers such as programmed death-1. Similar to conventional T cells, iNKT cells are influenced by the conditions of their activation. Conventional T cells receive signals through the following three types of receptors: (1 T cell receptor (TCR, (2 co-stimulation molecules, and (3 cytokine receptors. Unlike conventional T cells, which recognize peptide antigen presented by MHC class I or II, the TCRs of iNKT cells recognize lipid antigen in the context of the antigen presentation molecule CD1d (Signal 1. Co-stimulatory molecules can positively and negatively influence iNKT cell activation and function and skew the immune response (Signal 2. This study will review the background of iNKT cells and their co-stimulatory requirements for general function and in antitumor immunity. We will explore the impact of monoclonal antibody administration for both blocking inhibitory pathways and engaging stimulatory pathways on iNKT cell-mediated antitumor immunity. This review will highlight the incorporation of co-stimulatory molecules in antitumor dendritic cell vaccine strategies. The use of co-stimulatory intracellular signaling domains in chimeric antigen receptor-iNKT therapy will be assessed. Finally, we will explore the influence of innate-like receptors and modification of immunosuppressive cytokines (Signal 3 on cancer immunotherapy.

  4. Divergent Roles of Interferon-γ and Innate Lymphoid Cells in Innate and Adaptive Immune Cell-Mediated Intestinal Inflammation

    Science.gov (United States)

    Brasseit, Jennifer; Kwong Chung, Cheong K. C.; Noti, Mario; Zysset, Daniel; Hoheisel-Dickgreber, Nina; Genitsch, Vera; Corazza, Nadia; Mueller, Christoph

    2018-01-01

    Aberrant interferon gamma (IFNγ) expression is associated with the pathogenesis of numerous autoimmune- and inflammatory disorders, including inflammatory bowel diseases (IBD). However, the requirement of IFNγ for the pathogenesis of chronic intestinal inflammation remains controversial. The aim of this study was thus to investigate the role of IFNγ in experimental mouse models of innate and adaptive immune cell-mediated intestinal inflammation using genetically and microbiota-stabilized hosts. While we find that IFNγ drives acute intestinal inflammation in the anti-CD40 colitis model in an innate lymphoid cell (ILC)-dependent manner, IFNγ secreted by both transferred CD4 T cells and/or cells of the lymphopenic Rag1−/− recipient mice was dispensable for CD4 T cell-mediated colitis. In the absence of IFNγ, intestinal inflammation in CD4 T cell recipient mice was associated with enhanced IL17 responses; consequently, targeting IL17 signaling in IFNγ-deficient mice reduced T cell-mediated colitis. Intriguingly, in contrast to the anti-CD40 model of colitis, depletion of ILC in the Rag1−/− recipients of colitogenic CD4 T cells did not prevent induction of colonic inflammation. Together, our findings demonstrate that IFNγ represents an essential, or a redundant, pro-inflammatory cytokine for the induction of intestinal inflammation, depending on the experimental mouse model used and on the nature of the critical disease inducing immune cell populations involved. PMID:29416538

  5. Slp-76 is a critical determinant of NK cell-mediated recognition of missing-self targets

    Science.gov (United States)

    Lampe, Kristin; Endale, Mehari; Cashman, Siobhan; Fang, Hao; Mattner, Jochen; Hildeman, David; Hoebe, Kasper

    2015-01-01

    Absence of MHC class I expression is an important mechanism by which NK cells recognize a variety of target cells, yet the pathways underlying “missing-self” recognition, including the involvement of activating receptors, remain poorly understood. Using ENU mutagenesis in mice, we identified a germline mutant, designated Ace, with a marked defect in NK cell-mediated recognition and elimination of “missing-self” targets. The causative mutation was linked to chromosome 11 and identified as a missense mutation [Thr428Ile] in the SH2 domain of Slp-76—a critical adapter molecule downstream of ITAM-containing surface receptors. The Slp-76 Ace mutation behaved as a hypomorphic allele—while no major defects were observed in conventional T cell development/function, a marked defect in NK cell-mediated elimination of β2-Microglobulin (β2M)-deficient target cells was observed. Further studies revealed Slp-76 to control NK cell receptor expression and maturation, however, activation of Slp-76ace/ace NK cells through ITAM-containing NK cell receptors or allogeneic/tumor target cells appeared largely unaffected. Imagestream analysis of the NK-β2M−/− target cell synapse, revealed a specific defect in actin recruitment to the conjugate synapse in Slp-76ace/ace NK cells. Overall these studies establish Slp-76 as a critical determinant of NK cell development and NK cell-mediated elimination of missing-self target cells. PMID:25929249

  6. Concordance of CCR5 Genotypes that Influence Cell-Mediated Immunity and HIV-1 Disease Progression Rates

    Science.gov (United States)

    Catano, Gabriel; Chykarenko, Zoya A.; Mangano, Andrea; Anaya, J-M; Smith, Alison; Bologna, Rosa; Sen, Luisa; Clark, Robert A.; Lloyd, Andrew; Shostakovich-Koretskaya, Ludmila

    2011-01-01

    We used cutaneous delayed-type hypersensitivity responses, a powerful in vivo measure of cell-mediated immunity, to evaluate the relationships among cell-mediated immunity, AIDS, and polymorphisms in CCR5, the HIV-1 coreceptor. There was high concordance between CCR5 polymorphisms and haplotype pairs that influenced delayed-type hypersensitivity responses in healthy persons and HIV disease progression. In the cohorts examined, CCR5 genotypes containing -2459G/G (HHA/HHA, HHA/HHC, HHC/HHC) or -2459A/A (HHE/HHE) associated with salutary or detrimental delayed-type hypersensitivity and AIDS phenotypes, respectively. Accordingly, the CCR5-Δ32 allele, when paired with non-Δ32-bearing haplotypes that correlate with low (HHA, HHC) versus high (HHE) CCR5 transcriptional activity, associates with disease retardation or acceleration, respectively. Thus, the associations of CCR5-Δ32 heterozygosity partly reflect the effect of the non-▵32 haplotype in a background of CCR5 haploinsufficiency. The correlations of increased delayed-type hypersensitivity with -2459G/G-containing CCR5 genotypes, reduced CCR5 expression, decreased viral replication, and disease retardation suggest that CCR5 may influence HIV infection and AIDS, at least in part, through effects on cell-mediated immunity. PMID:21288827

  7. Specificity of two tests for the early diagnosis of bovine paratuberculosis based on cell-mediated immunity : the Johnin skin test and the gamma interferon assay

    NARCIS (Netherlands)

    Kalis, CHJ; Collins, MT; Hesselink, JW; Barkema, H.W.

    2003-01-01

    Paratuberculosis in cattle is a chronic debilitating infectious disease caused by Mycobacterium paratuberculosis. Control of paratuberculosis is based on tests that principally detect advanced stages of infections: faecal culture and serology. Tests measuring cell-mediated immunity (CMI) could

  8. Cell mediated immune responses in the placenta following challenge of vaccinated pregnant heifers with Neospora caninum.

    Science.gov (United States)

    Hecker, Y P; Cantón, G; Regidor-Cerrillo, J; Chianini, F; Morrell, E; Lischinsky, L; Ortega-Mora, L M; Innes, E A; Odeón, A; Campero, C M; Moore, D P

    2015-12-15

    The aim of the present study was to investigate and correlate the cell-mediated immune response and pathological changes at the maternal-fetal interface of Neospora-challenged pregnant cattle previously immunized with live and inactivated experimental vaccines. Pregnant heifers naïve to Neospora caninum were divided in 5 groups of 4 animals, each one immunized before mating: Group A heifers were intravenously (iv) immunized with 6.25 × 10(7) live tachyzoites of the NC-6 strain; group B heifers were immunized twice subcutaneously (sc) 3 weeks apart with native antigen extract of the NC-6 strain formulated with ISCOMs; group C heifers were sc immunized twice 3 weeks apart with three recombinant proteins (rNcSAG1, rNcHSP20, rNcGRA7) of the NC-1 strain formulated with ISCOMs; group D heifers were sc injected with sterile phosphate-buffered saline (PBS) and group E heifers received sc ISCOM-matrix (ISCOMs without antigen). All groups were iv-challenged with 4.7 × 10(7) NC-1 tachyzoites at 70 days of gestation. Heifers were culled at day 104 of gestation and placentomes were examined to evaluate lesions and local cellular immune responses using histopathology, immunohistochemistry and real time-PCR. Immunohistochemistry was performed using bovine leucocyte specific antibodies. Cytokine expression and levels (IFN-γ, IL-4, IL-10, IL-12 and TNF-α) were measured using real-time reverse transcription-PCR and ELISA, respectively. Minimal inflammation was observed in group A placentomes; while placentomes from group B, C, D and E had moderate to severe infiltration with CD3(+), CD4(+), γδ-T cells, CD8(+) cells and macrophages being more numerous in groups B and E placentomes, when compared with groups C and D (P<0.001). Cytokine levels were significantly increased in the caruncles of animals of groups B and C in comparison with the other animal groups (P < 0.001). The results from this study showed that the strongest cellular immune responses were observed in the

  9. Cell mediated therapeutics for cancer treatment: Tumor homing cells as therapeutic delivery vehicles

    Science.gov (United States)

    Balivada, Sivasai

    Many cell types were known to have migratory properties towards tumors and different research groups have shown reliable results regarding cells as delivery vehicles of therapeutics for targeted cancer treatment. Present report discusses proof of concept for 1. Cell mediated delivery of Magnetic nanoparticles (MNPs) and targeted Magnetic hyperthermia (MHT) as a cancer treatment by using in vivo mouse cancer models, 2. Cells surface engineering with chimeric proteins for targeted cancer treatment by using in vitro models. 1. Tumor homing cells can carry MNPs specifically to the tumor site and tumor burden will decrease after alternating magnetic field (AMF) exposure. To test this hypothesis, first we loaded Fe/Fe3O4 bi-magnetic NPs into neural progenitor cells (NPCs), which were previously shown to migrate towards melanoma tumors. We observed that NPCs loaded with MNPs travel to subcutaneous melanoma tumors. After alternating magnetic field (AMF) exposure, the targeted delivery of MNPs by the NPCs resulted in a mild decrease in tumor size (Chapter-2). Monocytes/macrophages (Mo/Ma) are known to infiltrate tumor sites, and also have phagocytic activity which can increase their uptake of MNPs. To test Mo/Ma-mediated MHT we transplanted Mo/Ma loaded with MNPs into a mouse model of pancreatic peritoneal carcinomatosis. We observed that MNP-loaded Mo/Ma infiltrated pancreatic tumors and, after AMF treatment, significantly prolonged the lives of mice bearing disseminated intraperitoneal pancreatic tumors (Chapter-3). 2. Targeted cancer treatment could be achieved by engineering tumor homing cell surfaces with tumor proteases cleavable, cancer cell specific recombinant therapeutic proteins. To test this, Urokinase and Calpain (tumor specific proteases) cleavable; prostate cancer cell (CaP) specific (CaP1 targeting peptide); apoptosis inducible (Caspase3 V266ED3)- rCasp3V266ED3 chimeric protein was designed in silico. Hypothesized membrane anchored chimeric protein (rCasp3V

  10. A Comparative Study of the Expression of Cytotoxic Proteins in Allergic Contact Dermatitis and Psoriasis

    Science.gov (United States)

    Yawalkar, Nikhil; Hunger, Robert E.; Buri, Caroline; Schmid, Simone; Egli, Fabienne; Brand, Christoph U.; Mueller, Christoph; Pichler, Werner J.; Braathen, Lasse R.

    2001-01-01

    Recent reports indicate that cytotoxic T cells are critically involved in contact hypersensitivity reactions in animals. In this study we sought to investigate the in vivo expression of cytotoxic granule proteins in the elicitation phase of allergic contact dermatitis in humans. Skin biopsy specimens were obtained from patients with allergic contact dermatitis (n = 8) and psoriasis (n = 6) and from controls with normal skin (n = 6). Expression of perforin and granzyme B was investigated by in situ hybridization and immunohistochemistry. In contrast to normal skin and psoriasis, a significant enhancement of perforin and granzyme B gene expression and immunoreactivity was observed in the mononuclear cell infiltrate of allergic contact dermatitis. Immunoreactivity for perforin and granzyme B was mainly found in the cytoplasm of lymphocytic cells, which were located in the dense perivascular infiltrate as well as at sites of marked spongiosis in the epidermis. Double immunostaining revealed that both CD4+ and CD8+ T cells are capable of expressing perforin and granzyme B. In conclusion, our data suggest that T-cell-mediated mechanisms involving cytotoxic granule proteins may elicit epidermal cell injury in vivo and thereby strongly contribute to the development of allergic contact dermatitis in humans. PMID:11238028

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

    Directory of Open Access Journals (Sweden)

    Fu-Nan Cho

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

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

    Science.gov (United States)

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

    2014-01-01

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

  13. Studies of Cell-Mediated Immunity Against Immune Disorders Using Synthetic Peptides and Rotating Bioreactor System

    Science.gov (United States)

    Sastry, Jagannadha K.

    1998-01-01

    We conducted a series of experiments using mouse immune-precursor cells, and observed that bioreactor culturing results in the loss of antigen-specific cytotoxic T lymphocyte (CTL) function. The reason for the abrogation of CTL function is microgravity conditions in the bioreactor, but not the antigen per se or its MHC restriction. Similarly, we observed that allostimulation of human PBMC in the bioreactor, but not in the T flask, resulted in the blunting of both allo-CTL function and the NK activity, indicating that the microgravity-associated functional defects are not unique to the mouse system. These results provide further confirmation to the microgravity-associated immune dysfunction, and constitute ground-based confirmatory data for those related to space-travel.

  14. Slp-76 is a critical determinant of NK-cell mediated recognition of missing-self targets.

    Science.gov (United States)

    Lampe, Kristin; Endale, Mehari; Cashman, Siobhan; Fang, Hao; Mattner, Jochen; Hildeman, David; Hoebe, Kasper

    2015-07-01

    Absence of MHC class I expression is an important mechanism by which NK cells recognize a variety of target cells, yet the pathways underlying "missing-self" recognition, including the involvement of activating receptors, remain poorly understood. Using ethyl-N-nitrosourea mutagenesis in mice, we identified a germline mutant, designated Ace, with a marked defect in NK cell mediated recognition and elimination of "missing-self" targets. The causative mutation was linked to chromosome 11 and identified as a missense mutation (Thr428Ile) in the SH2 domain of Slp-76-a critical adapter molecule downstream of ITAM-containing surface receptors. The Slp-76 Ace mutation behaved as a hypomorphic allele-while no major defects were observed in conventional T-cell development/function, a marked defect in NK cell mediated elimination of β2-microglobulin (β2M) deficient target cells was observed. Further studies revealed Slp-76 to control NK-cell receptor expression and maturation; however, activation of Slp-76(ace/ace) NK cells through ITAM-containing NK-cell receptors or allogeneic/tumor target cells appeared largely unaffected. Imagestream analysis of the NK-β2M(-/-) target cell synapse revealed a specific defect in actin recruitment to the conjugate synapse in Slp-76(ace/ace) NK cells. Overall these studies establish Slp-76 as a critical determinant of NK-cell development and NK cell mediated elimination of missing-self target cells in mice. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Humoral and cell-mediated immune responses in DNA immunized mink challenged with wild-type canine distemper virus

    DEFF Research Database (Denmark)

    Nielsen, Line; Søgaard, Mette; Karlskov-Mortensen, Peter

    2009-01-01

    The aim of the study was to investigate the different phases of the immune response after DNA immunization with the hemagglutinin and nucleoprotein genes from canine distemper virus (CDV). Although attenuated live CDV vaccines have effectively reduced the incidence of disease, canine distemper...... is still a problem worldwide. The broad host range of CDV creates a constant viral reservoir among wildlife animals. Our results demonstrated early humoral and cell-mediated immune responses (IFN-gamma) in DNA vaccinated mink compared to mock-vaccinated mink after challenge with a Danish wild-type CDV....... The DNA vaccine-induced immunity protected the natural host against disease development....

  16. CHARACTERISATION OF CELL-MEDIATED IMMUNE RESPONSE IN PIGS IN A CLINICAL CHALLENGE EXPERIMENT OF A VACCINE AGAINST MYCOPLASMA HYOSYNOVIAE

    DEFF Research Database (Denmark)

    Rasmussen, Josephine Skovgaard; Riber, Ulla; Lauritsen, Klara Tølbøll

    be due to increased systemic infection in the placebo group. Cell-mediated immune response was further characterised by four colour flow cytometry analysis of peripheral blood mononuclear cells (PBMCs) before Mhs challenge (day -1) and at days 6 and 9 after challenge. IFN-γ producing cells were found...... to be CD4 and especially CD4CD8 double positive T-cells simultaneously expressing CD25. Interestingly, the proportion of CD4CD8 double positive T-cells within the total population of CD4 positive cells increased in the vaccine group after challenge, indicating that generation of specific T-cell memory had...

  17. THE STATE OF CELL MEDIATED IMMUNITY AMONG HEPATITIS B SURFACE ,ANTGENI CARRIERS IN IRAN,

    Directory of Open Access Journals (Sweden)

    A. MASSOUD

    1987-06-01

    Full Text Available Cell-mediated immune (CMI s t a t us and sub- popul at i ons o f pe r ipheral b l ood lymphocytes were investigated in one hundre d volunt a ry blood donors who were car r ier s of Ag • HE S A signi f i c ant decr e ase of t otal T-cells observed in HB Ag carri e rs as compared t o normal controls. The percenS t age o f active T-cells a nd B-lymphocytes did not d i f f e r signi f icant ly between the t wo groups ."nAddi t ion of aut ologous serum from HE Ag c a r r iers t o s t heir l ymphocyt e s reduced the numbe r of detectabl e cells in HE Ag carriers . This reduction coul d be due to the s presence of a r osette i nhi bitory f actor in their serum. Our studies demonstrated a failur e o f CMI among HB Ags car r i ers detected by the l e ukocyte migr ation i nhibition (LMI test. This failure cannot be attributed to the presence of HE Ag-AB complexes in their serum. It is s possible that specific failure of CMI allows the hepatitis B virus to remain harmless in carriers a Hepatitis B surface-antigen (HE Ag; Hepatitis Bs coreantigen (HE Ag and Hepatitis Be-antigen (HE Ag, c e have been established as indicating ineffectivity in viral hepatitis B ({I, 6 , 20, 28."nA number of infected individuals also developed clini cal evidence of disease and HE Ag may s the serum of some subjects for a long rema•ln present I•n time (18. It has been suggested that to a defect in CMI, the persistence of HB Ag s whether liver disease is is related present or not, and impairment of the lymphocyte response to phytohaemagglutinin (PHA in this group is presented in evide•"nnee (8, •9 , 13, 24, 25 .In contrast, other workers report a normal respons e t o PHA in healthy carriers of HE Ag and s they concludE that the defective T-cell response is relat ed to the live!' disease rather than the immune system (31. Dudley et al (8 have suggested that liver damage occurring after hepatitis B infection, may be an effect of thymus-dependent lymphocytes (12."n

  18. Vitamin C plus hydrogel facilitates bone marrow stromal cell-mediated endometrium regeneration in rats

    Directory of Open Access Journals (Sweden)

    Huan Yang

    2017-11-01

    Full Text Available Abstract Background Intrauterine adhesion (IUA is a common uterine cavity disease which can be caused by mechanical damage that may eventually lead to infertility and pregnancy abnormalities. Since the effect of therapeutic drugs appears disappointing, cell therapy has emerged as an alternative choice for endometrium regeneration. The aim of this study is to investigate whether the combination of hydrogel Pluronic F-127 (PF-127, Vitamin C (Vc, and a bone marrow stromal cell (BMSC mixture could be a feasible strategy to improve the endometrial regeneration in a mechanical damage model of IUA in rats. Methods Firstly, PF-127 cytotoxicity and the effect of Vc was tested in vitro using the Annexin V/propidium iodide (PI apoptosis test, cell count kit (CCK growth test, and enzyme-linked immunosorbent assay (ELISA. For the establishment of the rat IUA model, a 2-mm transverse incision in the uterus was prepared at the upper end, and 1.5- to 2.0-cm endometrial damage was scraped. Rats were randomly assigned to five groups to investigate the combined strategy on IUA uterine regeneration: a sham group, an IUA control group, an IUA BMSC encapsulated in PF-127 plus Vc group, an IUA BMSC plus Vc group, and an IUA PF-127 plus Vc group. A cell mixture was injected into the uterine horn while making the IUA model. Eight weeks after cell transplantation, the rats were sacrificed and the uterine was dissected for analysis. Endometrial thickness, gland number, fibrosis area, and the expression of marker proteins for endometrial membrane were examined by hematoxylin and eosin staining, Masson’s staining, and immunohistochemistry. Results Vc promoted the survival and health of PF-127-encapsulated BMSCs in vitro. When this combination was transplanted in vivo, the endometrium showed better restoration as the endometrium membrane became thicker and had more glands and less fibrosis areas. The expression of cytokeratin, von Willebrand Factor (vWF, was also restored

  19. 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.

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

    Science.gov (United States)

    de Wit, Jelle; Souwer, Yuri; Jorritsma, Tineke; Klaasse Bos, Hanny; ten Brinke, Anja; Neefjes, Jacques; van Ham, S Marieke

    2010-09-27

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

  1. Cloning and expression analysis of nonspecific cytotoxic cell receptor 1 (Ls-NCCRP1) from red snapper (Lutjanus sanguineus).

    Science.gov (United States)

    Cai, Jia; Wei, Shina; Wang, Bei; Huang, Yucong; Tang, Jufen; Lu, Yishan; Wu, Zaohe; Jian, Jichang

    2013-09-01

    It is well known that nonspecific cytotoxic cells (NCCs) are kinds of natural killer cell mediated innate immune responses in teleosts. The nonspecific cytotoxic cell receptor protein 1 (NCCRP-1) is an important cell surface protein on NCC, which serves crucial functions in target cell recognition and cytotoxicity activation. In the present study, a nonspecific cytotoxic cell receptor protein NCCRP-1 (Ls-NCCRP1) was cloned from red snapper, Lutjanus sanguineus. The Ls-NCCRP1 cDNA is composed of 986bp with a 43bp of 5'-UTR, 702bp open reading frame (ORF) and 241bp 3'-UTR, encoding a polypeptide of 233 amino acids (GenBank accession no: ADK32635). Phylogenetic analysis revealed that Ls-NCCRP1 showed highest similarity to sea bream NCCRP-1. Quantitative real-time PCR (qRT-PCR) analysis showed that Ls-NCCRP1 had relatively high expression level in the head kidney, spleen and liver. After Vibrio alginolyticus infection, transcripts of Ls-NCCRP1 increased and reached its peak at 4h p.i. These results indicated that Ls-NCCRP1 may play an important role in innate immune response to bacteria. © 2013.

  2. Upregulated Expression of Cytotoxicity-Related Genes in IFN-γ Knockout Mice with Schistosoma japonicum Infection

    Directory of Open Access Journals (Sweden)

    Xiaotang Du

    2011-01-01

    Full Text Available It is well accepted that IFN-γ is important to the development of acquired resistance against murine schistosomiasis. However, the in vivo role of this immunoregulatory cytokine in helminth infection needs to be further investigated. In this study, parasite burden and host immune response were observed in IFN-γ knockout mice (IFNg KO infected with Schistosoma japonicum for 6 weeks. The results suggested that deficiency in IFN-γ led to decreased egg burden in mice, with low schistosome-specific IgG antibody response and enhanced activation of T cells during acute infection. Microarray and qRT-PCR data analyses showed significant upregulation of some cytotoxicity-related genes, including those from the granzyme family, tumor necrosis factor, Fas Ligand, and chemokines, in the spleen cells of IFNg KO mice. Furthermore, CD8+ cells instead of NK cells of IFNg KO mice exhibited increased transcription of cytotoxic genes compared with WT mice. Additionally, Schistosoma japonicum-specific egg antigen immunization also could activate CD8+ T cells to upregulate the expression of cytotoxic genes in IFNg KO mice. Our data suggest that IFN-γ is not always a positive regulator of immune responses. In certain situations, the disruption of IFN-γ signaling may up-regulate the cytotoxic T-cell-mediated immune responses to the parasite.

  3. Caspase 3 in dying tumor cells mediates post-irradiation angiogenesis

    Science.gov (United States)

    Zhang, Zhengxiang; Yu, Yang; Cheng, Jin; Gong, Yanping; Li, Chuan-Yuan; Huang, Qian

    2015-01-01

    Cytotoxic radiotherapy unfavorably induces tumor cells to generate various proangiogenic substances, promoting post-irradiation angiogenesis (PIA), which is one of major causes of radiotherapy failure. Though several studies have reported some mechanisms behind PIA, they have not yet described the beginning proangiogenic motivator buried in the irradiated microenvironment. In this work, we revealed that dying tumor cells induced by irradiation prompted PIA via a caspase 3 dependent mechanism. Proteolytic inactivation of caspase 3 in dying tumor cells by transducing a dominant-negative version weakened proangiogenic effects in vitro and in vivo. In addition, inhibition of caspase 3 activity suppressed tumor angiogenesis and tumorigenesis in xenograft mouse model. Importantly, we identified vascular endothelial growth factor (VEGF)-A as a downstream proangiogenic factor regulated by caspase 3 possibly through Akt signaling. Collectively, these findings indicated that besides acting as a key executioner in apoptosis, caspase 3 in dying tumor cells may play a central role in driving proangiogenic response after irradiation. Thus, radiotherapy in combination with caspase 3 inhibitors may be a novel promising therapeutic strategy to reduce tumor recurrence due to restrained PIA. PMID:26431328

  4. Poxvirus-encoded serpins do not prevent cytolytic T cell-mediated recovery from primary infections.

    Science.gov (United States)

    Müllbacher, A; Wallich, R; Moyer, R W; Simon, M M

    1999-06-15

    Previous observations that the highly conserved poxvirus-encoded serpins inhibit cytotoxic activities of alloreactive CTL via granule and/or Fas-mediated pathways was taken to indicate their involvement in immune evasion by poxviruses. We now show that interference with 51Cr release from target cells by ectromelia and cowpoxvirus is limited to alloreactive but not MHC-restricted CTL. The data are in support of the paramount importance of CTL and its effector molecule perforin in the recovery from primary ectromelia virus infection and question the role of serpins in the evasion of poxviruses from killing by CTL. Further analysis of poxvirus interference with target cell lysis by alloreactive CTL revealed that suppression primarily affects the Fas-mediated, and to a lesser extent, the granule exocytosis pathway. Serpin-2 is the main contributor to suppression for both killing pathways. In addition, inhibition of lysis was shown to be both target cell type- and MHC allotype-dependent. We hypothesize that differences in TCR affinities and/or state of activation between alloreactive and MHC-restricted CTL as well as the quality (origin) of target cells are responsible for the observed phenomenon.

  5. Second mitochondria-derived activator of caspase (SMAC) mimetic potentiates tumor susceptibility toward natural killer cell-mediated killing.

    Science.gov (United States)

    Brinkmann, Kerstin; Hombach, Andreas; Seeger, Jens Michael; Wagner-Stippich, Diana; Klubertz, Daniela; Krönke, Martin; Abken, Hinrich; Kashkar, Hamid

    2014-03-01

    Resistance to apoptosis is a hallmark of cancer, and represents an important mechanism of how tumor cells resist immune cell destruction. Mitochondria are the central regulators of the apoptotic machinery by releasing pro-apoptotic factors including cytochrome c and second mitochondria-derived activator of caspase (SMAC) upon mitochondrial outer membrane permeabilization (MOMP). Small molecules activating MOMP such as BH3 mimetics or antagonizers of the inhibitor of apoptosis proteins (IAPs) such as SMAC mimetics have recently engendered new optimism for a more individualized and effective cancer therapy. Here we show that a SMAC mimetic potentiates cancer cell killing by natural killer (NK) cells through reactivation of tumor cell apoptosis. Specifically, the SMAC mimetic enhances the susceptibility of tumor cells toward NK cell-mediated effector mechanisms involving death receptors and cytolytic granules containing perforin and granzymes by relieving caspase activity. Our data highlight for the first time the specific use of SMAC mimetics for boosting immune cell-mediated immunotherapy, representing a novel and promising approach in the treatment of cancer.

  6. Development and regulation of cell-mediated immune responses to the blood stages of malaria: implications for vaccine research.

    Science.gov (United States)

    Good, Michael F; Xu, Huji; Wykes, Michelle; Engwerda, Christian R

    2005-01-01

    The immune response to the malaria parasite is complex and poorly understood. Although antibodies and T cells can control parasite growth in model systems, natural immunity to malaria in regions of high endemicity takes several years to develop. Variation and polymorphism of antibody target antigens are known to impede immune responses, but these factors alone cannot account for the slow acquisition of immunity. In human and animal model systems, cell-mediated responses can control parasite growth effectively, but such responses are regulated by parasite load via direct effects on dendritic cells and possibly on T and B cells as well. Furthermore, high parasite load is associated with pathology, and cell-mediated responses may also harm the host. Inflammatory cytokines have been implicated in the pathogenesis of cerebral malaria, anemia, weight loss, and respiratory distress in malaria. Immunity without pathology requires rapid parasite clearance, effective regulation of the inflammatory anti-parasite effects of cellular responses, and the eventual development of a repertoire of antibodies effective against multiple strains. Data suggest that this may be hastened by exposure to malaria antigens in low dose, leading to augmented cellular immunity and rapid parasite clearance.

  7. Endogenous Tim-1 (Kim-1) promotes T-cell responses and cell-mediated injury in experimental crescentic glomerulonephritis.

    Science.gov (United States)

    Nozaki, Yuji; Nikolic-Paterson, David J; Snelgrove, Sarah L; Akiba, Hisaya; Yagita, Hideo; Holdsworth, Stephen R; Kitching, A Richard

    2012-05-01

    The T-cell immunoglobulin mucin 1 (Tim-1) modulates CD4(+) T-cell responses and is also expressed by damaged proximal tubules in the kidney where it is known as kidney injury molecule-1 (Kim-1). We sought to define the role of endogenous Tim-1 in experimental T-cell-mediated glomerulonephritis induced by sheep anti-mouse glomerular basement membrane globulin acting as a planted foreign antigen. Tim-1 is expressed by infiltrating activated CD4(+) cells in this model, and we studied the effects of an inhibitory anti-Tim-1 antibody (RMT1-10) on immune responses and glomerular disease. Crescentic glomerulonephritis, proliferative injury, and leukocyte accumulation were attenuated following treatment with anti-Tim-1 antibodies, but interstitial foxp3(+) cell accumulation and interleukin-10 mRNA were increased. T-cell proliferation and apoptosis decreased in the immune system along with a selective reduction in Th1 and Th17 cellular responses both in the immune system and within the kidney. The urinary excretion and renal expression of Kim-1 was reduced by anti-Tim-1 antibodies reflecting diminished interstitial injury. The effects of anti-Tim-1 antibodies were not apparent in the early phase of renal injury, when the immune response to sheep globulin was developing. Thus, endogenous Tim-1 promotes Th1 and Th17 nephritogenic immune responses and its neutralization reduces renal injury while limiting inflammation in cell-mediated glomerulonephritis.

  8. Gamma-irradiated scrub typhus immunogens: development of cell-mediated immunity after vaccination of inbred mice

    International Nuclear Information System (INIS)

    Jerrells, T.R.; Palmer, B.A.; Osterman, J.V.

    1983-01-01

    Mice immunized with three injections of gamma-irradiated Karp strain of Rickettsia tsutsugamushi were evaluated for the presence of cell-mediated immunity by using delayed-type hypersensitivity, antigen-induced lymphocyte proliferation, and antigen-induced lymphokine production. These animals also were evaluated for levels of circulating antibody after immunization as well as for the presence of rickettsemia after intraperitoneal challenge with viable Karp rickettsiae. After immunization with irradiated Karp rickettsiae, a demonstrable cell-mediated immunity was present as evidenced by delayed-type hypersensitivity responsiveness, lymphocyte proliferation, and production of migration inhibition factor and interferon by immune spleen lymphocytes. Also, a reduction in circulating rickettsiae was seen in mice immunized with irradiated rickettsiae after challenge with 1,000 50% mouse lethal doses of viable, homologous rickettsiae. All responses except antibody titer and reduction of rickettsemia were similar to the responses noted in mice immunized with viable organisms. Antibody levels were lower in mice immunized with irradiated rickettsiae than in mice immunized with viable rickettsiae. Furthermore, mice that were immunized with viable rickettsiae demonstrated markedly lower levels of rickettsemia after intraperitoneal challenge compared with either mice immunized with irradiated rickettsiae or nonimmunized mice

  9. Type I NKT-cell-mediated TNF-α is a positive regulator of NLRP3 inflammasome priming.

    Science.gov (United States)

    Chow, Melvyn T; Duret, Helene; Andrews, Daniel M; Faveeuw, Christelle; Möller, Andreas; Smyth, Mark J; Paget, Christophe

    2014-07-01

    The NLRP3 inflammasome plays a crucial role in the innate immune response to pathogens and exogenous or endogenous danger signals. Its activity must be precisely and tightly regulated to generate tailored immune responses. However, the immune cell subsets and cytokines controlling NLRP3 inflammasome activity are still poorly understood. Here, we have shown a link between NKT-cell-mediated TNF-α and NLRP3 inflammasome activity. The NLRP3 inflammasome in APCs was critical to potentiate NKT-cell-mediated immune responses, since C57BL/6 NLRP3 inflammasome-deficient mice exhibited reduced responsiveness to α-galactosylceramide. Importantly, NKT cells were found to act as regulators of NLRP3 inflammasome signaling, as NKT-cell-derived TNF-α was required for optimal IL-1β and IL-18 production by myeloid cells in response to α-galactosylceramide, by acting on the NLRP3 inflammasome priming step. Thus, NKT cells play a role in the positive regulation of NLRP3 inflammasome priming by mediating the production of TNF-α, thus demonstrating another means by which NKT cells control early inflammation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. CD16A activation of NK cells promotes NK cell proliferation and memory-like cytotoxicity against cancer cells.

    Science.gov (United States)

    Pahl, Jens H W; Koch, Joachim; Gotz, Jana-Julia; Arnold, Annette; Reusch, Uwe; Gantke, Thorsten; Rajkovic, Erich; Treder, Martin S; Cerwenka, Adelheid

    2018-03-07

    CD16A is a potent cytotoxicity receptor on human NK cells, which can be exploited by therapeutic bispecific antibodies. So far, the effects of CD16A-mediated activation on NK cell effector functions beyond classical antibody-dependent cytotoxicity have remained poorly elucidated. Here, we investigated NK cell responses after exposure to therapeutic antibodies such as the tetravalent bispecific antibody AFM13 (CD30/CD16A), designed for the treatment of Hodgkin lymphoma and other CD30+ lymphomas. Our results reveal that CD16A engagement enhanced subsequent IL2 and IL15¬-driven NK cell proliferation and expansion. This effect involved the up-regulation of CD25 (IL2Ralpha) and CD132 (gammac) on NK cells, resulting in increased sensitivity to low-dose IL2 or to IL15. CD16A engagement initially induced NK cell cytotoxicity. The lower NK cell reactivity observed one day after CD16A engagement could be recovered by re-culture in IL2 or IL15. After re-culture in IL2 or IL15, these CD16A-experienced NK cells exerted more vigorous IFNgamma production upon re-stimulation with tumor cells or cytokines. Importantly, after re-culture, CD16A-experienced NK cells also exerted increased cytotoxicity towards different tumor targets, mainly through the activating NK cell receptor NKG2D. Our findings uncover a role for CD16A engagement in priming NK cell responses to re-stimulation by cytokines and tumor cells, indicative of a memory-like functionality. Our study suggests that combination of AFM13 with IL2 or IL15 may boost NK cell anti-tumor activity in patients by expanding tumor-reactive NK cells and enhancing NK cell reactivity, even upon repeated tumor encounters. Copyright ©2018, American Association for Cancer Research.

  11. 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.

  12. 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...

  13. Structure-cytotoxicity relationships for dietary flavonoids

    DEFF Research Database (Denmark)

    Breinholt, V.; Dragsted, L.O.

    1998-01-01

    , and taxifolin. The structural requirements for cytotoxicity in the human cell lines, however, were less clear. Reduction of the cytotoxic response of the 3',4'-hydroxylated flavonoid, quercetin, by the hydroxyl radical scavenger mannitol and the metal chelator desferozamine suggests that reactive oxygen species......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...

  14. Triterpenes as Potentially Cytotoxic Compounds

    Directory of Open Access Journals (Sweden)

    Malwina Chudzik

    2015-01-01

    Full Text Available Triterpenes are compounds of natural origin, which have numerously biological activities: anti-cancer properties, anti-inflammatory, anti-oxidative, anti-viral, anti-bacterial and anti-fungal. These substances can be isolated from plants, animals or fungi. Nowadays, when neoplasms are main cause of death, triterpenes can become an alternative method for treating cancer because of their cytotoxic properties and chemopreventive activities.

  15. Mechanism of cytotoxicity of paraquat

    OpenAIRE

    Fukushima, Tetsuhito; Tanaka, Keiko; Lim, Heejin; Moriyama, Masaki

    2002-01-01

    Acute paraquat poisoning seems to be very complex because many possible mechanisms of paraquat cytotoxicity have been reported. Some may not be the cause of paraquat poisoning but the result or an accompanying phenomenon of paraquat action. The mechanism critical for cell damage is still unknown. Paraquat poisoning is probably a combination of several paraquat actions. Arguing which mechanism is more critical may not be important, and these clarified mechanisms should be connected and utilize...

  16. 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

  17. Cytotoxic Compounds from Brucea mollis

    Directory of Open Access Journals (Sweden)

    Mai Hung Thanh TUNG

    2016-09-01

    Full Text Available Ten compounds, including soulameanone (1, isobruceine B (2, 9-methoxy-canthin-6-one (3, bruceolline F (4, niloticine (5, octatriacontan-1-ol (6, bombiprenone (7, α-tocopherol (8, inosine (9, and apigenin 7-O-β-D-glucopyranoside (10, were isolated from the leaves, stems, and roots of Brucea mollis Wall. ex Kurz. Their structures were determined using one- and two-dimensional NMR spectroscopy and mass spectrometry. All compounds were evaluated for their cytotoxic activity against KB (human carcinoma of the mouth, LU-1 (human lung adenocarcinoma, LNCaP (human prostate adeno-carcinoma, and HL-60 (human promyelocytic leukemia cancer cell lines. Compound 2 showed significant cytotoxic activity against KB, LU-1, LNCaP, and HL-60 cancer cells with IC50 values of 0.39, 0.40, 0.34, and 0.23 μg/mL, respectively. In addition, compounds 3 and 5 showed significant cytotoxic activity against KB, LU-1, LNCaP, and HL-60 cancer cells with IC50 values around 1–4 μg/mL. Compounds 9-methoxycanthin-6-one (3 and niloticine (5 have been discovered for the first time from the Brucea genus.

  18. Comparative cytotoxicity of periodontal bacteria

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-11-01

    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.

  19. NK cells mediate the cumulative analgesic effect of electroacupuncture in a rat model of neuropathic pain.

    Science.gov (United States)

    Gao, Yong-Hui; Wang, Jun-Ying; Qiao, Li-Na; Chen, Shu-Ping; Tan, Lian-Hong; Xu, Qiu-Ling; Liu, Jun-Ling

    2014-08-26

    Cumulating evidence has revealed the effectiveness of acupuncture therapy in relieving pain via immunoregulation. However, its underlying mechanism remains unknown. The present study was designed to determine the changes of immunogenic responses at different time-points of electroacupuncture (EA) interventions in neuropathic pain rats. The neuropathic pain model was established by ligature of the left sciatic nerve to induce chronic constriction injury (CCI). EA was applied at Zusanli (ST36) and Yanglingquan (GB34) for the EA groups. The thermal pain threshold was detected with an algesia-detector. The subgroups of plasma and splenic lymphocytes were determined via fluorescence-activated cell sorting. Specific inflammatory cytokines were assayed using an ELISA-based bead multiplex assay. The activities of splenic natural killer (NK) cells and cytotoxic T lymphocytes were detected by methyl thiazolyl tetrazolium colorimetric method. For confirming the involvement of NK cell in EA-analgesia, anti-asialo-ganglio-N-tetraosylceramide (anti-asialo-GM1) antibody was given to CCI rats before EA. Following CCI, the thermal pain threshold of the affected hind footpad was significantly decreased, and increased from the 3rd day to the 12th day after EA interventions, presenting a time-dependent tendency from the 5th day on. From day 3 to 5 of EA interventions, the percentages and activity of splenic NK cells, concentrations of splenic interleukin-2 (IL-2) and beta-endorphin (β-EP) were significantly increased. Meanwhile, the concentrations of plasma IL-2, IL-1β and gamma-interferon (IFN-γ) were significantly decreased and returned to the normal level on day 12 following EA. Plasma transforming growth factor-β (TGF-β) levels were considerably upregulated on day 5 and 12 following EA. The CD4+/CD8+ T cell ratio was markedly downregulated compared with the control and CCI groups on day 5 and returned to the normal level on day 12 following EA. After depleting NK cells by

  20. Inducible nitric-oxide synthase plays a minimal role in lymphocytic choriomeningitis virus-induced, T cell-mediated protective immunity and immunopathology

    DEFF Research Database (Denmark)

    Bartholdy, C; Nansen, A; Christensen, Jeanette Erbo

    1999-01-01

    By using mice with a targetted disruption in the gene encoding inducible nitric-oxide synthase (iNOS), we have studied the role of nitric oxide (NO) in lymphocytic choriomeningitis virus (LCMV)-induced, T cell-mediated protective immunity and immunopathology. The afferent phase of the T cell......-mediated immune response was found to be unaltered in iNOS-deficient mice compared with wild-type C57BL/6 mice, and LCMV- induced general immunosuppression was equally pronounced in both strains. In vivo analysis revealed identical kinetics of virus clearance, as well as unaltered clinical severity of systemic....... This might suggest a role of NO in regulating vascular reactivity in the context of T cell-mediated inflammation. In conclusion, these findings indicate a minimal role for iNOS/NO in the host response to LCMV. Except for a reduced local oedema in the knockout mice, iNOS/NO seems to be redundant...

  1. Cell mediated lympholysis: CML. A microplate technique requiring few target cells and employing a new method of supernatant collection

    International Nuclear Information System (INIS)

    Hirschberg, A.; Thorsby, E.

    1977-01-01

    A micromethod for the 51 Cr release assay is described. Allogeneically induced cytotoxic lymphocytes are generated in mixed lymphocyte microcultures in the wells of microplates. Their cytotoxic capacity is assayed by adding 51 Cr-labelled PHA derived lymphoblasts directly into the microcultures with no pooling or transfer of the cytotoxic effector cells being required. The 51 Cr isotope released into the cell supernatants is collected by inserting a cellulose acetate absorption cartridge into each well. A glass fiber filter attached to the cartridge effectively separates the supernatant from the cellular elemets. This system allows the simultaneous collection of the supernatant from 96 wells, and can be used with either adherent or non-adherent target cells

  2. Environmental immunogens and T-cell-mediated responses in fibromyalgia: evidence for immune dysregulation and determinants of granuloma formation.

    Science.gov (United States)

    Shanklin, D R; Stevens, M V; Hall, M F; Smalley, D L

    2000-10-01

    Thirty-nine patients with fibromyalgia syndrome (FMS) according to American College of Rheumatology criteria were studied for cell-mediated sensitivity to environmental chemicals. Lymphocytes were tested by standard [(3)H]thymidine incorporation in vitro for T cell memory to 11 chemical substances. Concanavalin A (Con A) was used to demonstrate T cell proliferation. Controls were 25 contemporaneous healthy adults and 252 other concurrent standard controls without any aspect of FMS. Significantly higher (P P > 0.02) SI were found for cadmium and silicon. FMS patients showed sporadic responses to the specific substances tested, with no high-frequency result (>50%) and no obvious pattern. Mitogenic responses to Con A indicated some suppression of T cell functionality in FMS. Possible links between mitogenicity and immunogenic T cell proliferation, certain electrochemical specifics of granuloma formation, maintenance of connective tissue, and the fundamental nature of FMS are considered. Copyright 2000 Academic Press.

  3. Self-adjuvanting influenza candidate vaccine presenting epitopes for cell-mediated immunity on a proteinaceous multivalent nanoplatform.

    Science.gov (United States)

    Szurgot, Inga; Szolajska, Ewa; Laurin, David; Lambrecht, Benedicte; Chaperot, Laurence; Schoehn, Guy; Chroboczek, Jadwiga

    2013-09-13

    We exploit the features of a virus-like particle, adenoviral dodecahedron (Ad Dd), for engineering a multivalent vaccination platform carrying influenza epitopes for cell-mediated immunity. The delivery platform, Ad Dd, is a proteinaceous, polyvalent, and biodegradable nanoparticle endowed with remarkable endocytosis activity that can be engineered to carry 60 copies of a peptide. Influenza M1 is the most abundant influenza internal protein with the conserved primary structure. Two different M1 immunodominant epitopes were separately inserted in Dd external positions without destroying the particles' dodecahedric structure. Both kinds of DdFluM1 obtained through expression in baculovirus system were properly presented by human dendritic cells triggering efficient activation of antigen-specific T cells responses. Importantly, the candidate vaccine was able to induce cellular immunity in vivo in chickens. These results warrant further investigation of Dd as a platform for candidate vaccine, able to stimulate cellular immune responses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Simultaneous presence of endogenous retrovirus and herpes virus antigens has profound effect on cell-mediated immune responses

    DEFF Research Database (Denmark)

    Brudek, Tomasz; Christensen, Tove; Hansen, Hans Jacob

    2004-01-01

    Retroviruses have been suggested as possible pathogenic factors in multiple sclerosis (MS), supported by the observation that endogenous retroviruses are activated in MS patients. Different members of the herpes family of which several are neurotropic have also been suggested as factors in MS...... pathogenesis. Further, interactions between retroviruses and herpes viruses have been implied in the development of MS. The objective of the study was investigation of cell-mediated immune responses of MS patients to retrovirus and herpes virus antigens, particularly antigen combinations, with analyses...... retrovirus HERV-H and herpes virus antigens resulted in highly increased cellular immune responses among both the MS patients and healthy subjects. The increase was synergistic in character in most samples. Very pronounced effects were obtained using HHV-6A and HSV-1 antigens. Blast transformation assays...

  5. Ascaridia galli infection influences the development of both humoral and cell-mediated immunity after Newcastle Disease vaccination in chickens

    DEFF Research Database (Denmark)

    Pleidrup, Janne; Dalgaard, Tina S.; Norup, Liselotte R.

    2014-01-01

    on the immunological response to vaccination against other infectious diseases. The purpose of this study was to investigate whether A. galli infection influences vaccine-induced immunity to Newcastle Disease (ND) in chickens from an MHC-characterized inbred line. Chickens were experimentally infected with A. galli...... at 4 weeks of age or left as non-parasitized controls. At 10 and 13 weeks of age half of the chickens were ND-vaccinated and at 16 weeks of age, all chickens were challenged with a lentogenic strain of Newcastle disease virus (NDV). A. galli infection influenced both humoral and cell-mediated immune...... vaccinees as compared to non-parasitized vaccinees. However, more work is needed in order to determine if vaccine-induced protective immunity is impaired in A. galli-infected chickens....

  6. Chlamydia trachomatis and chlamydial heat shock protein 60-specific antibody and cell-mediated responses predict tubal factor infertility

    DEFF Research Database (Denmark)

    Tiitinen, A.; Surcel, H.-M.; Halttunen, M.

    2006-01-01

    BACKGROUND: To evaluate the role of Chlamydia trachomatis-induced humoral and cell-mediated immune (CMI) responses in predicting tubal factor infertility (TFI). METHODS: Blood samples were taken from 88 women with TFI and 163 control women. C. trachomatis and chlamydial heat shock protein 60 (CHSP......60)-specific immunoglobulin G (IgG) antibodies were analysed using enzyme-linked immunosorbent assay (ELISA) kits. Proliferative reactivity of peripheral blood mononuclear cells was studied in vitro against Chlamydia elementary body (EB) and recombinant CHSP60 antigens. RESULTS: C. trachomatis......-specific IgG antibodies were found more frequently (43.2 versus 13.5%), and the antibody levels were higher in the TFI cases than in the controls (P cases and 58.9% of the controls (P

  7. Effect of rosemary (Rosmarinus officinalis extract on weight, hematology and cell-mediated immune response of newborn goat kids

    Directory of Open Access Journals (Sweden)

    Borhan Shokrollahi

    2015-06-01

    Full Text Available This study aimed at evaluating the effects of different levels of rosemary (Rosmarinus officinalis extract on growth rate, hematology and cell-mediated immune response in Markhoz newborn goat kids. Twenty four goat kids (aged 7±3 days were randomly allotted to four groups with six replicates. The groups included: control, T1, T2 and T3 groups which received supplemented-milk with 0, 100, 200 and 400mg aqueous rosemary extract per kg of live body weight per day for 42 days. Body weights of kids were measured weekly until the end of the experiment. On day 42, 10 ml blood samples were collected from each kid through the jugular vein. Cell-mediated immune response was assessed through the double skin thickness after intradermal injection of phyto-hematoglutinin (PHA at day 21 and 42. No significant differences were seen in initial body weight, average daily gain (ADG and total gain. However, significant differences in globulin (P<0.05, and white blood cells (WBC (P<0.001 were observed. There were no significant differences in haemoglobin (Hb, packed cell volume (PCV, red blood cells (RBC, lymphocytes and neutrophils between the treatments. Skin thickness in response to intra dermal injection of PHA significantly increased in the treated groups as compared to the control group at day 42 (P<0.01 with the T3 group showing the highest response to PHA injection. In conclusion, the results indicated that aqueous rosemary extract supplemented-milk had a positive effect on immunity and skin thickness of newborn goat kids.

  8. Lactobacillus rhamnosus CRL1505 nasal administration improves recovery of T-cell mediated immunity against pneumococcal infection in malnourished mice.

    Science.gov (United States)

    Barbieri, N; Herrera, M; Salva, S; Villena, J; Alvarez, S

    2017-05-30

    Immunobiotic lactic acid bacteria have become an interesting alternative for the prevention of respiratory infections. Previously, we demonstrated that the nasal administration of Lactobacillus rhamnosus CRL1505, during repletion of malnourished mice, resulted in diminished susceptibility to the challenge with the respiratory pathogen Streptococcus pneumoniae. Considering the known alterations induced by malnutrition on T lymphocytes and the importance of this cell population on the protection against respiratory pathogens, we aimed to study the effect of L. rhamnosus CRL1505 nasal administration on the recovery of T cell-mediated defences against pneumococcal infection in malnourished mice under nutritional recovery. Malnourished mice received a balanced conventional diet (BCD) for seven days or BCD for seven days with nasal L. rhamnosus CRL1505 supplementation during last two days of the treatment. After the treatments mice were infected with S. pneumoniae. Flow cytometry studies were carried out in bone marrow, thymus, spleen and lung to study T cells, and Th 1 /Th 2 cytokine profiles were determined in broncho-alveolar lavages and serum. The administration of CRL1505 strain to malnourished mice under recovery reduced quantitative and qualitative alterations of CD4 + T cells in the bone marrow, thymus, spleen and lung induced by malnutrition. In addition, CRL1505 treatment augmented Th 2 -cytokines (interleukin 10 and 4) in respiratory and systemic compartments after pneumococcal infection. These results show that modulation of CD4 + T lymphocytes induced by L. rhamnosus CRL1505 has an important role in the beneficial effect induced by this strain on the recovery of malnourished mice. These data also indicate that nasally administered L. rhamnosus CRL1505 may represent a non-invasive alternative to modulate and improve the T cell-mediated immunity against respiratory pathogens in immunocompromised malnourished hosts.

  9. The CD39 molecule defines distinct cytotoxic subsets within alloactivated human CD8-positive cells.

    Science.gov (United States)

    Gouttefangeas, C; Mansur, I; Schmid, M; Dastot, H; Gélin, C; Mahouy, G; Boumsell, L; Bensussan, A

    1992-10-01

    Lymphocyte activation induces or increases the expression of several surface structures, none of which is characteristic of an activated cell subset. In particular, structures such as CD45RO, CD25, CD26, CD49b, CD54, CD71 are expressed by the vast majority of lymphocytes at various times following in vitro activation. CD39 molecules were originally identified on activated B lymphocytes and have recently been described on activated T cell clones. In the present report, we have characterized phenotypically and functionally defined cell subsets generated during an in vitro allostimulation. Results indicated that the percentage of CD39+ cells reached a maximum at day 6 and remained stable thereafter. We demonstrate that CD39 expression allows the identification within the allosensitized CD8+ cytotoxic cells of distinct subsets of cells mediating allo cytotoxic T lymphocyte or natural killer (NK)-like reactivity. More precisely, CD8+CD39+ alloactivated cells mainly mediate specific killer activity, whereas CD8+CD39- alloactivated cells predominantly exhibit NK-like reactivity. Further, we show a high functional correlation associated with the lack of CD39 expression on NK-like alloactivated CD8+ cells, while there is no association with CD56 or CD57 NK-associated structures.

  10. The adaptor molecule SAP plays essential roles during invariant NKT cell cytotoxicity and lytic synapse formation.

    Science.gov (United States)

    Das, Rupali; Bassiri, Hamid; Guan, Peng; Wiener, Susan; Banerjee, Pinaki P; Zhong, Ming-Chao; Veillette, André; Orange, Jordan S; Nichols, Kim E

    2013-04-25

    The adaptor molecule signaling lymphocytic activation molecule-associated protein (SAP) plays critical roles during invariant natural killer T (iNKT) cell ontogeny. As a result, SAP-deficient humans and mice lack iNKT cells. The strict developmental requirement for SAP has made it difficult to discern its possible involvement in mature iNKT cell functions. By using temporal Cre recombinase-mediated gene deletion to ablate SAP expression after completion of iNKT cell development, we demonstrate that SAP is essential for T-cell receptor (TCR)-induced iNKT cell cytotoxicity against T-cell and B-cell leukemia targets in vitro and iNKT-cell-mediated control of T-cell leukemia growth in vivo. These findings are not restricted to the murine system: silencing RNA-mediated suppression of SAP expression in human iNKT cells also significantly impairs TCR-induced cytolysis. Mechanistic studies reveal that iNKT cell killing requires the tyrosine kinase Fyn, a known SAP-binding protein. Furthermore, SAP expression is required within iNKT cells to facilitate their interaction with T-cell targets and induce reorientation of the microtubule-organizing center to the immunologic synapse (IS). Collectively, these studies highlight a novel and essential role for SAP during iNKT cell cytotoxicity and formation of a functional IS.

  11. Interleukin-17A Promotes CD8+ T Cell Cytotoxicity To Facilitate West Nile Virus Clearance.

    Science.gov (United States)

    Acharya, Dhiraj; Wang, Penghua; Paul, Amber M; Dai, Jianfeng; Gate, David; Lowery, Jordan E; Stokic, Dobrivoje S; Leis, A Arturo; Flavell, Richard A; Town, Terrence; Fikrig, Erol; Bai, Fengwei

    2017-01-01

    CD8 + T cells are crucial components of immunity and play a vital role in recovery from West Nile virus (WNV) infection. Here, we identify a previously unrecognized function of interleukin-17A (IL-17A) in inducing cytotoxic-mediator gene expression and promoting CD8 + T cell cytotoxicity against WNV infection in mice. We find that IL-17A-deficient (Il17a -/- ) mice are more susceptible to WNV infection and develop a higher viral burden than wild-type (WT) mice. Interestingly, the CD8 + T cells isolated from Il17a -/- mice are less cytotoxic and express lower levels of cytotoxic-mediator genes, which can be restored by supplying recombinant IL-17A in vitro and in vivo Importantly, treatment of WNV-infected mice with recombinant IL-17A, as late as day 6 postinfection, significantly reduces the viral burden and increases survival, suggesting a therapeutic potential for IL-17A. In conclusion, we report a novel function of IL-17A in promoting CD8 + T cell cytotoxicity, which may have broad implications in other microbial infections and cancers. Interleukin-17A (IL-17A) and CD8 + T cells regulate diverse immune functions in microbial infections, malignancies, and autoimmune diseases. IL-17A is a proinflammatory cytokine produced by diverse cell types, while CD8 + T cells (known as cytotoxic T cells) are major cells that provide immunity against intracellular pathogens. Previous studies have demonstrated a crucial role of CD8 + T cells in recovery from West Nile virus (WNV) infection. However, the role of IL-17A during WNV infection remains unclear. Here, we demonstrate that IL-17A protects mice from lethal WNV infection by promoting CD8 + T cell-mediated clearance of WNV. In addition, treatment of WNV-infected mice with recombinant IL-17A reduces the viral burden and increases survival of mice, suggesting a potential therapeutic. This novel IL-17A-CD8 + T cell axis may also have broad implications for immunity to other microbial infections and cancers, where CD8 + T cell

  12. Cytotoxic Compounds from Aloe megalacantha

    Directory of Open Access Journals (Sweden)

    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.

  13. Virus-specific HLA-restricted lysis of herpes simplex virus-infected human monocytes and macrophages mediated by cytotoxic T lymphocytes

    International Nuclear Information System (INIS)

    Torpey, D.J. III.

    1987-01-01

    Freshly-isolated peripheral blood human monocytes and 5 day in vitro cultured macrophages were infected with herpes simplex virus type 1 (HSV-1), labeled with 51 Cr, and used as target cells in a 12-14 hour cell-mediated cytotoxicity assay. Mononuclear leukocytes (MNL) from HSV-1 non-immune individuals, whether unstimulated or stimulated with HSV-1 antigen, did not mediate significant lysis of either target cell. HSV-immune MNL, both freshly-isolated and cultured for 5 days without antigen, demonstrated only low levels of natural killer (NK) cell-mediate lysis. MNL from HSV-immune individuals incubated for 5 days in vitro with HSV-1 antigen mediated significant virus-specific lysis of both target cells. Mean virus-specific lysis of autologous monocytes was 8.5(/+-/2.0)% compared to a three-fold greater virus-specific lysis of autologous macrophages. Greater than 70% of this lytic activity was mediated by Leu-11-negative, T3-positive cytotoxic T lymphocytes (CTL). Allogeneic target cells lacking a common HLA determinant were not significantly lysed while T8-positive CTL mediated infrequent lysis of target cells sharing a common HLA-A and/or HLA-B determinant. T4-positive lymphocytes were demonstrated to be the predominant cell mediating lysis of autologous target cells and allogeneic target cells sharing both HLA-A and/or HLA-B plus HLA-DR determinants with the CTL; the T4-positive cell was the sole CTL mediator of lysis of allogeneic target cells having a common HLA-DR determinant

  14. Isolation of Mallory bodies and an attempt to demonstrate cell mediated immunity to Mallory body isolate in patients with alcoholic liver disease

    DEFF Research Database (Denmark)

    Gluud, C; Hardt, F; Aldershvile, J

    1981-01-01

    in haematoxylin-eosin stained smears. Electron microscopy confirmed the presence of Mallory bodies in the isolates. The Mallory body isolate was used as antigen in the agarose leucocyte migration inhibition test in order to test the cell-mediated immunity. No significant difference in leucocyte migration...

  15. Vaccine-induced T cell-mediated immunity plays a critical role in early protection against pseudorabies virus (suid herpes virus type 1) infection in pigs

    NARCIS (Netherlands)

    Rooij, van E.M.A.; Bruin, de M.G.M.; Visser-Hendriksen, de Y.E.; Middel, W.G.; Boersma, W.J.A.; Bianchi, A.T.J.

    2004-01-01

    The aim of our study was to evaluate the relative importance of antibody and T cell-mediated immunity in protection against pseudorabies virus (suid herpes virus type 1) infection in pigs. We induced different levels of immune responses by using: (1) a modified live vaccine; (2) the same modified

  16. Characteristics of Cell-mediated, Anti-listerial Immunity Induced by A Naturally Avirulent Listeria monocytogenes Serotype 4a Strain HCC23

    Science.gov (United States)

    The characteristics of cell-mediated, anti-listerial immune response initiated by an avirulent Listeria monocytogenes serotype 4a strain HCC23 was assessed. Similar to virulent strain EGD, avirulent strain HCC23 grew readily within macrophage-like J774 cells, but nonhemolytic strain ATCC 15313 did n...

  17. Nucleotide sequence analysis of a human monoclonal antibody TONO-1 with cytotoxic potential for T-leukemia/lymphoma cells.

    Science.gov (United States)

    Numasaki, M; Nakamura, K; Fukuoka, Y; Saeki, H; Hanai, N; Kudo, T

    2001-01-15

    A human monoclonal antibody (HuMab) TONO-1 (IgM, lambda) recognizes cell surface antigens associated primarily with human T-leukemia/lymphoma cells. In this study, we investigated the reactivity against T-leukemia/lymphoma cells in detail, cytotoxic potential and primary nucleotide and deduced amino acid sequences of the rearranged heavy and light chains of the HuMab TONO-1. Expression of the molecules (TONO-1 Ags) detected by a HuMab TONO-1 was significantly heterogeneous even in the same T-leukemia/lymphoma cell lines HPB-MLT and MOLT-4F. The flow cytometric curves showed an unusual broad-based spread of fluorescence intensity. HuMab TONO-1 was shown to have the ability to kill the T-leukernia/lymphoma cells efficiently in the presence of rabbit complements. However, HuMab TONO-1 did not demonstrate significant antibody-dependent cellular cytotoxic activity. Furthermore, HuMab TONO-1 heavy and light chain variable regions were cloned, sequenced and analyzed. HuMab TONO-1 uses a V(H) gene member of the V(H)IV gene family V(H)71-4, and is productively rearranged with the germ line D(H) gene D(XP')1, and the germ line J(H)5 gene with multiple somatic mutations. HuMab TONO-1 Vlambda belongs to the lambda light chain variable subgroup I family and is derived from the Vlambdalc germ line gene Humlv1042, and germ line gene Jlambda1 without somatic mutations. The results reveal that the production of HuMab TONO-1, with cytotoxic potential for human T-leukemia/lymphoma cells, is achieved by rearrangement of the V(H)71-4/Humlv1042 germ line variable region gene combination, that is associated with the autoimmune repertoire.

  18. Circulating blocking factors of lymphoid-cell cytotoxicity in x-ray-induced rat small-bowel adenocarcinoma

    International Nuclear Information System (INIS)

    Stevens, R.H.; Brooks, G.P.; Osborne, J.W.

    1979-01-01

    Circulating blocking factors capable of abrogating cell-mediated immune responses measured by in vitro lymphoid-cell cytotoxicity were identified in the sera of Holtzman outbred rats 6 to 9 months after a single exposure of only the temporarily exteriorized, hypoxic ileum and jejunum to 1700 to 2000 R of X radiation. Such factors were found to exist in the serum of every animal exposed to the ionizing radiation regardless of whether a visibly identifiable small-bowel adenocarcinoma existed or subsequently would develop. Protection of cultured x-ray-induced rat small-bowel cancer cells from destruction by tumor-sensitized lymphoid cells as measured by the release of lactoperoxidase-catalyzed radioiodinated membrane proteins from the tumor target cells was conferred by the action of the blocking factors at both effector and target cell levels. The results of this study demonstrate that exposure of only the rat small intestine to ionizing radiation leads to elaboration of circulating factors identifiable several months postirradiation which will block cell-mediated immune responses directed against cancer cells developing in the exposed tissue

  19. Recurrent Vulvovaginal Candidiasis: Could It Be Related to Cell-Mediated Immunity Defect in Response to Candida Antigen?

    Directory of Open Access Journals (Sweden)

    Zahra Talaei

    2017-09-01

    Full Text Available Background Recurrent vulvovaginal candidiasis (RVVC is a common cause of morbidity affecting millions of women worldwide. Patients with RVVC are thought to have an underlying immunologic defect. This study has been established to evaluate cell-mediated immunity defect in response to candida antigen in RVVC cases. Materials and Methods Our cross-sectional study was performed in 3 groups of RVVC patients (cases, healthy individuals (control I and known cases of chronic mucocutaneous candidiasis (CMC (control II. Patients who met the inclusion criteria of RVVC were selected consecutively and were allocated in the case group. Peripheral blood mononuclear cells were isolated and labeled with CFSE and proliferation rate was measured in exposure to candida antigen via flow cytometry. Results T lymphocyte proliferation in response to candida was significantly lower in RVVC cases (n=24 and CMC patients (n=7 compared to healthy individuals (n=20, P0.05. Family history of primary immunodeficiency diseases (PID differed significantly among groups (P=0.01, RVVC patients has family history of PID more than control I (29.2 vs. 0%, P=0.008 but not statistically different from CMC patients (29.2 vs. 42.9%, P>0.05. Prevalence of atopy was greater in RVVC cases compared to healthy individuals (41.3 vs. 15%, P=0.054. Lymphoproliferative activity and vaginal symptoms were significantly different among RVVC cases with and without allergy (P=0.01, P=0.02. Conclusion Our findings revealed that T cells do not actively proliferate in response to Candida antigen in some RVVC cases. So it is concluded that patients with cell-mediated immunity defect are more susceptible to recurrent fungal infections of vulva and vagina. Nonetheless, some other cases of RVVC showed normal function of T cells. Further evaluations showed that these patients suffer from atopy. It is hypothesized that higher frequency of VVC in patients with history of atopy might be due to allergic response

  20. Host genetic background influences the response to the opportunistic Pseudomonas aeruginosa infection altering cell-mediated immunity and bacterial replication.

    Science.gov (United States)

    De Simone, Maura; Spagnuolo, Lorenza; Lorè, Nicola Ivan; Rossi, Giacomo; Cigana, Cristina; De Fino, Ida; Iraqi, Fuad A; Bragonzi, Alessandra

    2014-01-01

    Pseudomonas aeruginosa is a common cause of healthcare-associated infections including pneumonia, bloodstream, urinary tract, and surgical site infections. The clinical outcome of P. aeruginosa infections may be extremely variable among individuals at risk and patients affected by cystic fibrosis. However, risk factors for P. aeruginosa infection remain largely unknown. To identify and track the host factors influencing P. aeruginosa lung infections, inbred immunocompetent mouse strains were screened in a pneumonia model system. A/J, BALB/cJ, BALB/cAnNCrl, BALB/cByJ, C3H/HeOuJ, C57BL/6J, C57BL/6NCrl, DBA/2J, and 129S2/SvPasCRL mice were infected with P. aeruginosa clinical strain and monitored for body weight and mortality up to seven days. The most deviant survival phenotypes were observed for A/J, 129S2/SvPasCRL and DBA/2J showing high susceptibility while BALB/cAnNCrl and C3H/HeOuJ showing more resistance to P. aeruginosa infection. Next, one of the most susceptible and resistant mouse strains were characterized for their deviant clinical and immunological phenotype by scoring bacterial count, cell-mediated immunity, cytokines and chemokines profile and lung pathology in an early time course. Susceptible A/J mice showed significantly higher bacterial burden, higher cytokines and chemokines levels but lower leukocyte recruitment, particularly neutrophils, when compared to C3H/HeOuJ resistant mice. Pathologic scores showed lower inflammatory severity, reduced intraluminal and interstitial inflammation extent, bronchial and parenchymal involvement and diminished alveolar damage in the lungs of A/J when compared to C3H/HeOuJ. Our findings indicate that during an early phase of infection a prompt inflammatory response in the airways set the conditions for a non-permissive environment to P. aeruginosa replication and lock the spread to other organs. Host gene(s) may have a role in the reduction of cell-mediated immunity playing a critical role in the control of P

  1. Synthesis, characterisation, nuclease and cytotoxic activity of ...

    Indian Academy of Sciences (India)

    Complexes 1 and 2 were evaluated for their nuclease and in vitro anti-tumor activities against human breast and colorectal cancer cell lines. The DNA cleavage and cytotoxic assays revealed that both 1 and 2 are effective in cleaving DNA, while the cytotoxic activity of 1 is better than 2 in both human colon and breast cancer ...

  2. Cytotoxic sesquiterpene lactones from Inula britannica.

    Science.gov (United States)

    Park, E J; Kim, J

    1998-12-01

    Cytotoxicity-guided fractionation of the flowers of Inula britannica led to the isolation of four sesquiterpene lactones, 4 alpha, 6 alpha-dihydroxyeudesman-8 beta, 12-olide (1), ergolide (2), 8-epi-helenalin (3), and bigelovin (4). Compound 1 was isolated as a new natural product. These compounds showed cytotoxicity against human tumor cell lines.

  3. 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.

  4. 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.

  5. The effect of vitamin B6 deficiency on cytotoxic immune responses of T cells, antibodies, and natural killer cells, and phagocytosis by macrophages.

    Science.gov (United States)

    Ha, C; Miller, L T; Kerkvliet, N I

    1984-05-01

    The effect of vitamin B6 on cytotoxic immune responses of T cells, natural killer (NK) cells, cytotoxic antibody production, and macrophage phagocytosis was assessed in 5-week-old female C57B1/6 mice. Mice were fed 20% casein diets with pyridoxine (PN) added at 7, 1, 0.1, or 0 mg/kg diet, which represents 700, 100, 10, and 0% of requirement, respectively. Compared to mice fed 7 or 1 mg PN diet, animals fed 0 or 0.1 mg PN diet showed significantly reduced primary splenic and peritoneal T-cell-mediated cytotoxicity (CMC). Animals fed 0 mg PN diet also showed significantly depressed secondary T CMC of splenic and peritoneal lymphocytes against P815 tumor cells. Complement-dependent antibody-mediated cytotoxicity against P815 cells, phagocytosis of SRBC by macrophages, and native and interferon-induced NK cell activities against YAC cells were not affected by the level of vitamin B6 intake. The percentage of macrophages present in the peritoneal exudate cells was increased in animals fed the 0 mg PN diet. The immune responses were not enhanced or altered by the excess intake of vitamin B6 (7 mg PN). It appears that vitamin B6 is an essential nutrient for maintenance of normal T-cell function in vivo.

  6. Latent Adeno-Associated Virus Infection Elicits Humoral but Not Cell-Mediated Immune Responses in a Nonhuman Primate Model

    Science.gov (United States)

    Hernandez, Yosbani J.; Wang, Jianming; Kearns, William G.; Loiler, Scott; Poirier, Amy; Flotte, Terence R.

    1999-01-01

    Latent infection with wild-type (wt) adeno-associated virus (AAV) was studied in rhesus macaques, a species that is a natural host for AAV and that has some homology to humans with respect to the preferred locus for wt AAV integration. Each of eight animals was infected with an inoculum of 1010 IU of wt AAV, administered by either the intranasal, intramuscular, or intravenous route. Two additional animals were infected intranasally with wt AAV and a helper adenovirus (Ad), while one additional animal was inoculated with saline intranasally as a control. There were no detectable clinical or histopathologic responses to wt AAV administration. Molecular analyses, including Southern blot, PCR, and fluorescence in situ hybridization, were performed 21 days after infection. These studies indicated that AAV DNA sequences persisted at the sites of administration, albeit at low copy number, and in peripheral blood mononuclear cells. Site-specific integration into the AAVS1-like locus was observed in a subset of animals. All animals, except those infected by the intranasal route with wt AAV alone, developed a humoral immune response to wt AAV capsid proteins, as evidenced by a ≥fourfold rise in anti-AAV neutralizing titers. However, only animals infected with both wt AAV and Ad developed cell-mediated immune responses to AAV capsid proteins. These findings provide some insights into the nature of anti-AAV immune responses that may be useful in interpreting results of future AAV-based gene transfer studies. PMID:10482608

  7. A Possible Role for CD8+ T Lymphocytes in the Cell-Mediated Pathogenesis of Pemphigus Vulgaris

    Directory of Open Access Journals (Sweden)

    Federica Giurdanella

    2013-01-01

    Full Text Available Pemphigus vulgaris (PV is an autoimmune blistering disease whose pathogenesis involves both humoral and cell-mediated immune response. Though the pathogenetic role of autoantibodies directed against desmoglein 3 is certain, a number of other factors have been suggested to determine acantholysis in PV. In this study we examined the possible role of CD8+ T cells in the development of acantholysis by a passive transfer of PV autoantibodies using CD8 deficient mice, and we also studied the inflammatory infiltrate of PV skin lesions by immunohistochemical staining. The results of the immunohistochemical staining to study the expression of CD3, CD4, and CD8 in PV skin lesions showed that CD4+ are more expressed than CD8+ in the inflammatory infiltrate of PV lesions, confirming the data of the previous literature. The passive transfer study showed a lower incidence of pemphigus in the group of CD8 deficient mice compared to the control one of wild-type mice. These results suggest that CD8+ T cells may play a role in the pathogenesis of PV, perhaps through the Fas/FasL pathway.

  8. Phytoconstituents of Jatropha curcas L. leaves and their immunomodulatory activity on humoral and cell-mediated immune response in chicks.

    Science.gov (United States)

    Abd-Alla, Howaida I; Moharram, Fatma A; Gaara, Ahmed H; El-Safty, Mounir M

    2009-01-01

    A novel biflavone di-C-glucoside, 6,6"-di-C-beta-D-glucopyranoside-methylene-(8,8")-biapigenin (1), was isolated from the leaves of Jatropha curcas L. (Euphorbiaceae), together with six known compounds; apigenin 7-O-beta-D-neohesperidoside (2), apigenin 7-O-beta-D-galactoside (3), orientin (4), vitexin (5), vicenin II (6), and apigenin (7). Their structures were determined on the basis of extensive chemical and spectroscopic analyses (UV, NMR and HRESI-MS). The immunomodulatory effect of an 80% aqueous methanol extract (AME) and compounds 1-5 (0.25 mg/kg body wt) to one-day-old specific pathogen-free (SPF) chicks was determined. Stimulation of both humoral and cell-mediated seroresponse was observed, especially those of AME and compound 1. Remarkable effective increases of the antibody titers, lymphocyte and macrophage cells, in blood were recorded. SPF chicks treated with the tested samples exhibited protection against Newcastle disease challenge virus after being vaccinated.

  9. Anti-inflammatory effect of curcumin on mast cell-mediated allergic responses in ovalbumin-induced allergic rhinitis mouse.

    Science.gov (United States)

    Zhang, Ning; Li, Hong; Jia, Jihui; He, Mingqiang

    2015-01-01

    Curcumin has commonly been used for the treatment of various allergic diseases. However, its precise anti-allergic rhinitis effect and mechanism remain unknown. In the present study, the effect of curcumin on allergic responses in ovalbumin (OVA)-induced allergic rhinitis mouse was investigated. We explored the effect of curcumin on the release of allergic inflammatory mediators, such as histamine, OVA-specific IgE, and inflammatory cytokines. Also, we found that curcumin improved rhinitis symptoms, inhibited the histopathological changes of nasal mucosa, and decreased the serum levels of histamine, OVA-specific IgE and TNF-α in OVA-induced allergic rhinitis mice. In addition, curcumin suppressed the production of inflammatory cytokines, such as TNF-α, IL-1β, IL-6 and IL-8. Moreover, curcumin significantly inhibited PMA-induced p-ERK, p-p38, p-JNK, p-Iκ-Bα and NF-κB. These findings suggest that curcumin has an anti-allergic effect through modulating mast cell-mediated allergic responses in allergic rhinitis, at least partly by inhibiting MAPK/NF-κB pathway. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Inhibition of Mast Cell-Mediated Allergic Responses by Arctii Fructus Extracts and Its Main Compound Arctigenin.

    Science.gov (United States)

    Kee, Ji-Ye; Hong, Seung-Heon

    2017-11-01

    The Arctium lappa seeds (Arctii Fructus) and its major active compound, arctigenin (ARC), are known to have anticancer, antiobesity, antiosteoporosis, and anti-inflammatory activities. However, the effect of Arctii Fructus and ARC on mast cell-mediated allergic inflammation and its associated mechanism have not been elucidated. Therefore, we attempted to investigate the antiallergic activity of Arctii Fructus and ARC on mast cells and experimental mouse models. Arctii Fructus water extract (AFW) or ethanol extract (AFE) and ARC reduced the production of histamine and pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6, IL-8, and TNF-α in mast cells. AFW, AFE, and ARC inhibited phosphorylation of MAPKs and NF-κB in activated mast cells. Moreover, IgE-mediated passive cutaneous anaphylaxis and compound 48/80-induced anaphylactic shock were suppressed by AFW, AFE, and ARC administration. These results suggest that Arctii Fructus and ARC are potential therapeutic agents against allergic inflammatory diseases.

  11. Circumvention of regulatory CD4(+) T cell activity during cross-priming strongly enhances T cell-mediated immunity.

    Science.gov (United States)

    Heit, Antje; Gebhardt, Friedemann; Lahl, Katharina; Neuenhahn, Michael; Schmitz, Frank; Anderl, Florian; Wagner, Hermann; Sparwasser, Tim; Busch, Dirk H; Kastenmüller, Kathrin

    2008-06-01

    Immunization with purified antigens is a safe and practical vaccination strategy but is generally unable to induce sustained CD8(+) T cell-mediated protection against intracellular pathogens. Most efforts to improve the CD8(+) T cell immunogenicity of these vaccines have focused on co-administration of adjuvant to support cross-presentation and dendritic cell maturation. In addition, it has been shown that CD4(+) T cell help during the priming phase contributes to the generation of protective CD8(+) memory T cells. In this report we demonstrate that the depletion of CD4(+) T cells paradoxically enhances long-lasting CD8-mediated protective immunity upon protein vaccination. Functional and genetic in vivo inactivation experiments attribute this enhancement primarily to MHC class II-restricted CD4(+) regulatory T cells (Treg), which appear to physiologically suppress the differentiation process towards long-living effector memory T cells. Since, in functional terms, this suppression by Treg largely exceeds the positive effects of conventional CD4(+) T cell help, even the absence of all CD4(+) T cells or lack of MHC class II-mediated interactions on priming dendritic cells result in enhanced CD8(+) T cell immunogenicity. These findings have important implications for the improvement of vaccines against intracellular pathogens or tumors, especially in patients with highly active Treg.

  12. Effect of response to backtest and housing condition on cell-mediated and humoral immunity in adult pigs.

    Science.gov (United States)

    Geverink, N A; Parmentier, H K; de Vries Reilingh, G; Schouten, W G P; Gort, G; Wiegant, V M

    2004-01-01

    Several recent studies in juvenile pigs demonstrated a relationship between the degree of resistance displayed early in life in a so-called "backtest" and parameters of cell-mediated and humoral immunity. Some of the immune characteristics were reported to depend on the interaction between backtest classification and housing system. In the present study, the effects of backtest classification and housing condition on immune reactivity in adult gilts were examined. At 10 and 17 days of age, female piglets were subjected to the backtest. In this test, each piglet is restrained on its back for 1 min and the number of escape attempts is scored. Pigs classified as high resisting (HR) or low resisting (LR) were selected and housed in groups of six gilts. At 7 months of age, half of the gilts were housed in individual stalls. At 12 months of age, gilts were challenged by immunization with DNP-KLH. Control gilts were treated similarly with a placebo. Blood samples were drawn prior to immunization (Day 0) and weekly thereafter until Day 28. No significant effects of backtest type on cellular and humoral responses against KLH were found. Furthermore, being housed in stalls as compared to groups had no consequences for the immune response and did not induce differences between HR and LR gilts. Differences in behavior and physiology found previously between HR and LR gilts, particularly in gilts in stall housing, may thus be of relatively little importance for immune-related health.

  13. The Ameliorative Effect of Sophoricoside on Mast Cell-Mediated Allergic Inflammation in Vivo and in Vitro

    Directory of Open Access Journals (Sweden)

    Jae-Young Um

    2013-05-01

    Full Text Available Sophoricoside exhibits numerous pharmacological effects, including anti- inflammatory and anti-cancer actions, yet the exact mechanism that accounts for the anti-allergic effects of sophoricoside is not completely understood. The aim of the present study was to elucidate whether and how sophoricoside modulates the mast cell-mediated allergic inflammation in vitro and in vivo. We investigated the pharmacological effects of sophoricoside on both compound 48/80 or histamine-induced scratching behaviors and 2,4-dinitrochlorobenzene (DNCB-induced atopic dermatitis in mice. Additionally, to find a possible explanation for the anti-inflammatory effects of sophoricoside, we evaluated the effects of sophoricoside on the production of histamine and inflammatory cytokines and activation of nuclear factor-κB (NF-κB and caspase-1 in phorbol 12-myristate 13-acetate plus calcium ionophore A23187 (PMACI-stimulated human mast cells (HMC-1. The finding of this study demonstrated that sophoricoside reduced compound 48/80 or histamine-induced scratching behaviors and DNCB-induced atopic dermatitis in mice. Additionally, sophoricoside inhibited the production of inflammatory cytokines as well as the activation of NF-κB and caspase-1 in stimulated HMC-1. Collectively, the findings of this study provide us with novel insights into the pharmacological actions of sophoricoside as a potential molecule for use in the treatment of allergic inflammation diseases.

  14. The anti-microbial peptide SR-0379 stimulates human endothelial progenitor cell-mediated repair of peripheral artery diseases.

    Science.gov (United States)

    Lee, Tae Wook; Heo, Soon Chul; Kwon, Yang Woo; Park, Gyu Tae; Yoon, Jung Won; Kim, Seung-Chul; Jang, Il Ho; Kim, Jae Ho

    2017-10-01

    Ischemia is a serious disease, characterized by an inadequate blood supply to an organ or part of the body. In the present study, we evaluated the effects of the anti-microbial peptide SR-0379 on the stem cell-mediated therapy of ischemic diseases. The migratory and tube-forming abilities of human endothelial progenitor cells (EPCs) were enhanced by treatment with SR-0379 in vitro. Intramuscular administration of SR-0379 into a murine ischemic hindlimb significantly enhanced blood perfusion, decreased tissue necrosis, and increased the number of blood vessels in the ischemic muscle. Moreover, co-administration of SR-0379 with EPCs stimulated blood perfusion in an ischemic hindlimb more than intramuscular injection with either SR-0379 or EPCs alone. This enhanced blood perfusion was accompanied by a significant increase in the number of CD31- and α-SMApositive blood vessels in ischemic hindlimb. These results suggest that SR-0379 is a potential drug candidate for potentiating EPC-mediated therapy of ischemic diseases. [BMB Reports 2017; 50(10): 504-509].

  15. CD4+ type II NKT cells mediate ICOS and programmed death-1-dependent regulation of type 1 diabetes

    DEFF Research Database (Denmark)

    Kadri, Nadir; Korpos, Eva; Gupta, Shashank

    2012-01-01

    Type 1 diabetes (T1D) is a chronic autoimmune disease that results from T cell-mediated destruction of pancreatic ß cells. CD1d-restricted NKT lymphocytes have the ability to regulate immunity, including autoimmunity. We previously demonstrated that CD1d-restricted type II NKT cells, which carry...... diverse TCRs, prevented T1D in the NOD mouse model for the human disease. In this study, we show that CD4(+) 24aß type II NKT cells, but not CD4/CD8 double-negative NKT cells, were sufficient to downregulate diabetogenic CD4(+) BDC2.5 NOD T cells in adoptive transfer experiments. CD4(+) 24aß NKT cells...... exhibited a memory phenotype including high ICOS expression, increased cytokine production, and limited display of NK cell markers, compared with double-negative 24aß NKT cells. Blocking of ICOS or the programmed death-1/programmed death ligand 1 pathway was shown to abolish the regulation that occurred...

  16. CD4(+) type II NKT cells mediate ICOS and programmed death-1-dependent regulation of type 1 diabetes.

    Science.gov (United States)

    Kadri, Nadir; Korpos, Eva; Gupta, Shashank; Briet, Claire; Löfbom, Linda; Yagita, Hideo; Lehuen, Agnes; Boitard, Christian; Holmberg, Dan; Sorokin, Lydia; Cardell, Susanna L

    2012-04-01

    Type 1 diabetes (T1D) is a chronic autoimmune disease that results from T cell-mediated destruction of pancreatic β cells. CD1d-restricted NKT lymphocytes have the ability to regulate immunity, including autoimmunity. We previously demonstrated that CD1d-restricted type II NKT cells, which carry diverse TCRs, prevented T1D in the NOD mouse model for the human disease. In this study, we show that CD4(+) 24αβ type II NKT cells, but not CD4/CD8 double-negative NKT cells, were sufficient to downregulate diabetogenic CD4(+) BDC2.5 NOD T cells in adoptive transfer experiments. CD4(+) 24αβ NKT cells exhibited a memory phenotype including high ICOS expression, increased cytokine production, and limited display of NK cell markers, compared with double-negative 24αβ NKT cells. Blocking of ICOS or the programmed death-1/programmed death ligand 1 pathway was shown to abolish the regulation that occurred in the pancreas draining lymph nodes. To our knowledge, these results provide for the first time cellular and molecular information on how type II CD1d-restricted NKT cells regulate T1D.

  17. 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.

  18. Cytotoxic chalcones from some Indonesian Cryptocarya

    Science.gov (United States)

    Kurniadewi, F.; Syah, Y. M.; Juliawaty, L. D.; Hakim, E. H.; Koyama, K.; Kinoshita, K.

    2017-07-01

    Malignant tumors are one of the main causes of death in the world. Until now the search for cytotoxic (antitumor) compounds from nature, particularly from plants, is being a continuation activities. One group of plants that produce potential cytotoxic compounds is the Cryptocarya, one of the large genera of the Lauraceae family. As a part of our chemical and cytotoxic evaluation of the Cryptocarya species, we examined three species of Indonesian Cryptocarya. The sample of the wood of C. konishii hayata was collected from Cibodas Botanical Garden, West Java while the stem bark of C. phoebeopsis and C. cagayanensis were obtained from Sorong, Papua. Our investigation of flavonoid constituents on these species afforded three chalcone compounds i.e. desmethylinfectocaryone (1), infectocaryone (2) and cryptocaryone (3). The molecular structures of the isolated compounds were determined based on spectroscopic data, including UV, IR, 1D and 2D NMR. Cytotoxic effects of the compounds were evaluated using MTT [3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide] assay. Compound 1, 2 and 3 displayed strong cytotoxic properties (IC50 cells whereas 2 and 3 exhibited strong cytotoxicity properties against HCT116 (colon cancer). Cryptocaryone (3) also showed moderate cytotoxic properties (IC50 cells.

  19. Investigation of internalization and cytotoxicity of 125I-[Tyr3]-octreotide in NCI-H446 cell line

    International Nuclear Information System (INIS)

    Sun Junjie; Fan Wo; Xu Yujie; Zhang Youjiu; Zhu Ran; Hu Mingjiang

    2004-01-01

    Objective: To investigate the [Tyr 3 ]-octreotide (TOC) internalizing capacity of NCI-H446 cell line, and the cytotoxicity of 125 I-TOC in NCI-H446 cell line. To assess the therapeutic radiopharmaceutical potentiality of 125 I-TOC for the somatostatin receptor (SSTR) positive tumor. Methods: NCI-H446 cells were incubated together with 125 I-TOC for different periods of time, the amount of internalized 125 I-TOC and the 125 I-TOC bound on the cellular nucleus were detected with γ counter, respectively. The viability of the cells was analyzed by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay at different time points with various doses of 125 I-TOC, free 125 I and TOC. Results: 125 I-TOC was internalized into the nucleus and bound on the nucleus in a time-dependent manner. 125 I-TOC bound on the nucleus increased to the highest level at 24 h, the amount of nucleus bound 125 I-TOC at 24 h was 7 times higher than that at 0.5 h. Cytotoxicity of 125 I-TOC in SSTR positive NCI-H446 cells was also dose- and time-dependent. The supreme effect of cytotoxicity was found at 96 h with 74 kBq 125 I-TOC, the survival ratio of cells was reduced to (44.8 ± 7.2)%. Conclusions: 125 I-TOC can be internalized into SSTR positive cells mediated by SSTR. The NCI-H446 cells can be killed by Auger electron emitting from 125 I-TOC. Effect of cytotoxicity showed dose- and time-dependent

  20. Cytotoxicity of anthraquinones from the roots of Pentas schimperi towards multi-factorial drug-resistant cancer cells.

    Science.gov (United States)

    Kuete, Victor; Donfack, Arno R Nanfack; Mbaveng, Armelle T; Zeino, Maen; Tane, Pierre; Efferth, Thomas

    2015-08-01

    Multidrug resistance in cancer represents a major problem in chemotherapy. The present study was designed to assess the cytotoxicity of anthraquinones from Pentas schimperi, namely damnacanthal (1), damnacanthol (2), 3-hydroxy-2-hydroxymethyl anthraquinone (3) and schimperiquinone B (4) against nine drug-sensitive and multidrug resistant (MDR) cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of the above compounds, whilst caspase-Glo assay was used to detect the activation of caspases enzymes by compounds 1 and 2. Cell cycle, mitochondrial membrane potential (MMP) and levels of reactive oxygen species were all analyzed via flow cytometry. Anthraquinones 1 and 2 displayed cytotoxic effects with IC50 values below 81 μM on all the nine tested cancer cell lines whilst 3 and 4 displayed selective activities. The recorded IC50 values for compounds 1 and 2 ranged from 3.12 μM and 12.18 μM (towards leukemia CCRF-CEM cells) and from 30.32 μM and 80.11 μM (towards gliobastoma U87MG.ΔEGFR cells) respectively, and from 0.20 μM (against CCRF-CEM cells) to 195.12 μM (against CEM/ADR5000 cells) for doxorubicin. Compounds 1 and 2 induced apoptosis in CCRF-CEM leukemia cells, mediated by the disruption of the MMP and increase in ROS production. Anthraquinones from Pentas schimperi and mostly 1 and 2 are potential cytotoxic natural products that deserve more investigations to develop novel antineoplastic drugs against multifactorial drug resistant cancers.

  1. Cytotoxicity of the methanol extracts of Elephantopus mollis, Kalanchoe crenata and 4 other Cameroonian medicinal plants towards human carcinoma cells.

    Science.gov (United States)

    Kuete, Victor; Fokou, Fabrice W; Karaosmanoğlu, Oğuzhan; Beng, Veronique P; Sivas, Hülya

    2017-05-25

    Cancer still constitutes one of the major health concerns globally, causing serious threats on patients, their families, and the healthcare system. In this study, the cytotoxicity of the methanol extract of Elephantopus mollis whole plant (EMW), Enantia chlorantha bark (ECB), Kalanchoe crenata leaves (KCL), Lophira alata bark (LAB), Millettia macrophylla leaves (MML) and Phragmanthera capitata leaves (PCL) towards five human solid cancer cell lines and normal CRL2120 fibroblasts, was evaluated. Extracts were subjected to qualitative chemical screening of their secondary metabolite contents using standard methods. The cytotoxicity of samples was evaluated using neutral red uptake (NR) assay meanwhile caspase activation was detected by caspase-Glo assay. Flow cytometry was used to analyze the cell cycle distribution and the mitochondrial membrane potential (MMP) whilst spectrophotometry was used to measure the levels of reactive oxygen species (ROS). Phytochemical analysis revealed the presence of polyphenols, triterpenes and sterols in all extracts. The IC 50 values of the best samples ranged from 3.29 μg/mL (towards DLD-1 colorectal adenocarcinoma cells) to 24.38 μg/mL (against small lung cancer A549 cells) for EMW, from 2.33 μg/mL (mesothelioma SPC212 cells) to 28.96 μg/mL (HepG2 hepatocarcinoma) for KCL, and from 0.04 μg/mL (towards SPC212 cells) to 0.55 μg/mL (towards A549 cells) for doxorubicin. EMW induced apoptosis in MCF-7 cells mediated by MMP loss and increased ROS production whilst KCL induced apoptosis via ROS production. This study provides evidences of the cytotoxicity of the tested plant extract and highlights the good activity of Elephantopus mollis and Kalanchoe crenata. They deserve more exploration to develop novel cytotoxic drugs.

  2. Oxidative stress and cytotoxicity elicited lipid peroxidation in hemocytes of Bombyx mori larva infested with dipteran parasitoid, Exorista bombycis.

    Science.gov (United States)

    Pooja, Makwana; Pradeep, Appukuttan Nair R; Hungund, Shambhavi P; Sagar, Chandrashekhar; Ponnuvel, Kangayam M; Awasthi, Arvind K; Trivedy, Kanika

    2017-12-20

    Parasitization of silkworm, Bombyx mori by invasive larva of dipteran parasitoid Exorista bombycis caused upto 20% revenue loss in sericulture. The parasitism was successful by suppressing host immune system however mechanism of immune suppression induced by E. bombycis is unknown which is unravelled here. The infestation induced cytotoxic symptoms in host hemocytes, such as vacuolated cytoplasm, porous plasma membrane, indented nuclei with condensed chromatin and dilated RER. One of the markers of necrosis is cell permeabilization, which can be measured as released lactate dehydrogenase (LDH). LDH level showed significantly (P<0.01) high release into extracellular medium in vitro after exposure of hemocytes to parasitoid larval tissue protein compared with control revealing membrane permeability and loss of cell integrity. At five minutes after exposure, cytotoxicity was 43% and was increased to 99% at 3h. The cytotoxicity is signalled by increased content of hydrogen peroxide (H2O2) causing lipid peroxidation followed by porosity in plasma membrane. A test for lipid peroxidation by measurement of lipid peroxidation breakdown product, malondialdehyde (MDA) revealed significant increase in peroxidation from one to 24 h post-invasion, with maximum at 12 h (P<0.008). Level of reactive oxygen species measured as H2O2 production increased from 6 to 12 h post-invasion and continued to increase significantly (P<0.03) reaching maximum at 48 h. These observations reveal that dipteran endoparasitoid invasion induced H2O2 production in the hemocytes causing cytotoxicity, lipid peroxidation and membrane porosity that suppressed both humoral- and cell-mediated immune responses of hemocytes in B. mori.

  3. Opposing effects of CXCR3 and CCR5 deficiency on CD8+ T cell-mediated inflammation in the central nervous system of virus-infected mice

    DEFF Research Database (Denmark)

    de Lemos, Carina; Christensen, Jeanette Erbo; Nansen, Anneline

    2005-01-01

    T cells play a key role in the control of viral infection in the CNS but may also contribute to immune-mediated cell damage. To study the redundancy of the chemokine receptors CXCR3 and CCR5 in regulating virus-induced CD8+ T cell-mediated inflammation in the brain, CXCR3/CCR5 double-deficient mice...... and therefore protect mice against the otherwise fatal CD8+ T cell-mediated immune attack. Contrary to expectations, the accumulation of mononuclear cells in cerebrospinal fluid was only slightly delayed compared with mice with normal expression of both receptors. Even more surprising, CXCR3/CCR5 double......-deficient mice were more susceptible to intracerebral infection than CXCR3-deficient mice. Analysis of effector T cell generation revealed an accelerated antiviral CD8+ T cell response in CXCR3/CCR5 double-deficient mice. Furthermore, while the accumulation of CD8+ T cells in the neural parenchyma...

  4. Cornuside inhibits mast cell-mediated allergic response by down-regulating MAPK and NF-κB signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Li, Liangchang [Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Yanbian University, Yanji, 133002 (China); Jin, Guangyu [Yanbian University Hospital, Medicine College, Yanbian University, Yanji, 133000 (China); Jiang, Jingzhi [Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Yanbian University, Yanji, 133002 (China); Zheng, Mingyu; Jin, Yan [College of Pharmacy, Yanbian University, Yanji, 133002 (China); Lin, Zhenhua [Department of Pathology & Cancer Research Center, Yanbian University Medical College, Yanji, 133002 (China); Li, Guangzhao [Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Yanbian University, Yanji, 133002 (China); Choi, Yunho, E-mail: why76@jbnu.ac.kr [Department of Anatomy, Medical School, Institute for Medical Sciences, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Yan, Guanghai, E-mail: ghyan2015@sina.com [Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Yanbian University, Yanji, 133002 (China)

    2016-04-29

    Aims: The present study is to investigate the effect of cornuside on mast cell-mediated allergic response, as well as its possible mechanisms of action. Methods: To test the anti-allergic effects of cornuside in vivo, local extravasation was induced by local injection of anti-dinitrophenyl immunoglobulin E (IgE) followed by intravenous antigenic challenge in passive cutaneous anaphylaxis model rats. Mast cell viability was determined using MTT assay. Histamine content from rat peritoneal mast cells was measured by the radioenzymatic method. To investigate the mechanisms by which cornuside affects the reduction of histamine release, the levels of calcium uptake were measured. To examine whether cornuside affects the expression of pro-inflammatory cytokines, Western blotting and ELISA were carried out. Results: Oral administration of cornuside inhibited passive cutaneous anaphylaxis in rats. Presence of cornuside attenuated IgE-induced histamine release from rat peritoneal mast cells. The inhibitory effect of cornuside on histamine release was mediated by the modulation of intracellular calcium. In addition, cornuside decreased phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187-stimulated production and secretion of pro-inflammatory cytokines such as TNF-α and IL-6 in human mast cells. The inhibitory effect of cornuside on pro-inflammatory cytokines was dependent on nuclear factor-κB and p38 mitogen-activated protein kinase. Conclusions: The present study provides evidence that cornuside inhibits mast cell-derived inflammatory allergic reactions by blocking histamine release and pro-inflammatory cytokine expression. Furthermore, in vivo and in vitro anti-allergic effects of cornuside suggest a possible therapeutic application of this agent in inflammatory allergic diseases.

  5. Vault nanocapsules as adjuvants favor cell-mediated over antibody-mediated immune responses following immunization of mice.

    Directory of Open Access Journals (Sweden)

    Upendra K Kar

    Full Text Available BACKGROUND: Modifications of adjuvants that induce cell-mediated over antibody-mediated immunity is desired for development of vaccines. Nanocapsules have been found to be viable adjuvants and are amenable to engineering for desired immune responses. We previously showed that natural nanocapsules called vaults can be genetically engineered to elicit Th1 immunity and protection from a mucosal bacterial infection. The purpose of our study was to characterize immunity produced in response to OVA within vault nanoparticles and compare it to another nanocarrier. METHODOLOGY AND PRINCIPAL FINDINGS: We characterized immunity resulting from immunization with the model antigen, ovalbumin (OVA encased in vault nanocapsules and liposomes. We measured OVA responsive CD8(+ and CD4(+ memory T cell responses, cytokine production and antibody titers in vitro and in vivo. We found that immunization with OVA contain in vaults induced a greater number of anti-OVA CD8(+ memory T cells and production of IFNγ plus CD4(+ memory T cells. Also, modification of the vault body could change the immune response compared to OVA encased in liposomes. CONCLUSIONS/SIGNIFICANCE: These experiments show that vault nanocapsules induced strong anti-OVA CD8(+ and CD4(+ T cell memory responses and modest antibody production, which markedly differed from the immune response induced by liposomes. We also found that the vault nanocapsule could be modified to change antibody isotypes in vivo. Thus it is possible to create a vault nanocapsule vaccine that can result in the unique combination of immunogen-responsive CD8(+ and CD4(+ T cell immunity coupled with an IgG1 response for future development of vault nanocapsule-based vaccines against antigens for human pathogens and cancer.

  6. Trypanosoma cruzi Adjuvants Potentiate T Cell-Mediated Immunity Induced by a NY-ESO-1 Based Antitumor Vaccine

    Science.gov (United States)

    Junqueira, Caroline; Guerrero, Ana Tereza; Galvão-Filho, Bruno; Andrade, Warrison A.; Salgado, Ana Paula C.; Cunha, Thiago M.; Ropert, Catherine; Campos, Marco Antônio; Penido, Marcus L. O.; Mendonça-Previato, Lúcia; Previato, José Oswaldo; Ritter, Gerd; Cunha, Fernando Q.; Gazzinelli, Ricardo T.

    2012-01-01

    Immunological adjuvants that induce T cell-mediate immunity (TCMI) with the least side effects are needed for the development of human vaccines. Glycoinositolphospholipids (GIPL) and CpGs oligodeoxynucleotides (CpG ODNs) derived from the protozoa parasite Trypanosoma cruzi induce potent pro-inflammatory reaction through activation of Toll-Like Receptor (TLR)4 and TLR9, respectively. Here, using mouse models, we tested the T. cruzi derived TLR agonists as immunological adjuvants in an antitumor vaccine. For comparison, we used well-established TLR agonists, such as the bacterial derived monophosphoryl lipid A (MPL), lipopeptide (Pam3Cys), and CpG ODN. All tested TLR agonists were comparable to induce antibody responses, whereas significant differences were noticed in their ability to elicit CD4+ T and CD8+ T cell responses. In particular, both GIPLs (GTH, and GY) and CpG ODNs (B344, B297 and B128) derived from T. cruzi elicited interferon-gamma (IFN-γ) production by CD4+ T cells. On the other hand, the parasite derived CpG ODNs, but not GIPLs, elicited a potent IFN-γ response by CD8+ T lymphocytes. The side effects were also evaluated by local pain (hypernociception). The intensity of hypernociception induced by vaccination was alleviated by administration of an analgesic drug without affecting protective immunity. Finally, the level of protective immunity against the NY-ESO-1 expressing melanoma was associated with the magnitude of both CD4+ T and CD8+ T cell responses elicited by a specific immunological adjuvant. PMID:22567144

  7. Schwann Cell-Mediated Preservation of Vision in Retinal Degenerative Diseases via the Reduction of Oxidative Stress: A Possible Mechanism.

    Science.gov (United States)

    Mahmoudzadeh, Raziyeh; Heidari-Keshel, Saeed; Lashay, Alireza

    2016-01-01

    After injury to the central nervous system (CNS), regeneration is often inadequate, except in the case of remyelination. This remyelination capacity of the CNS is a good example of a stem/precursor cell-mediated renewal process. Schwann cells have been found to act as remyelinating agents in the peripheral nervous system (PNS), but several studies have highlighted their potential role in remyelination in the CNS too. Schwann cells are able to protect and support retinal cells by secreting growth factors such as brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, and basic fibroblast growth factor. Retinal degenerative diseases can be highly debilitating, and they are a major concern in countries with an ageing populations. One of the leading causes of permanent loss of vision in the West is a retinal degenerative disease known as age-related macular degeneration (AMD). In the United States, nearly 1.75 million people over the age of 40 have advanced AMD, and it is estimated that this number will increase to approximately 3 million people by 2020. One of the most common pathways involved in the initiation and development of retinal diseases is the oxidative stress pathway. In patients with diabetes, Schwann cells have been shown to be able to secrete large amounts of antioxidant enzymes that protect the PNS from the oxidative stress that results from fluctuations in blood glucose levels. This antioxidant ability may be involved in the mechanism by which Schwann cells are able to promote reconstruction in the CNS, especially in individuals with retinal injuries and degenerative diseases.

  8. Immunomodulatory activity of geranial, geranial acetate, gingerol, and eugenol essential oils: evidence for humoral and cell-mediated responses.

    Science.gov (United States)

    Farhath, Seema; Vijaya, Pp; Vimal, Manivannan

    2013-01-01

    The immunomodulatory effect of geranial, geranial acetate, gingerol, and eugenol essential oils were evaluated by studying humoral and cell-mediated immune responses. The essential oils were evaluated for immunomodulatory activity in in vivo studies, using rats as the animal model. The essential oils were tested for hypersensitivity and hemagglutination reactions, using sheep red blood cells (SRBC) as the antigen while sodium carboxy methyl cellulose (SCMC) served as the control in all the tests. Orally administrated essential oils showed a significant increase of test parameters, viz., haemagglutinating antibody titre (HAT) and delayed type hypersensitivity (DTH) response. In rats immunized with sheep RBC, essential oils enhanced the humoral antibody response to the antigen and significantly potentiated the cellular immunity by facilitating the foot pad thickness response to sheep RBC in sensitized rats with doses of 50-800 mg/ml. Haemagglutination titre of geraniol showed the highest increase of 139.3±6.38 and with 5.9±0.7 DTH, respectively. For geranial acetate, the haemagglutination titre showed a moderate increase of 87.5±5.9 and highest increase in DTH with 5.9±0.8, respectively. Using gingerol, the haemagglutination titre showed a moderate increase with 88.2±6.306 and DTH 3.5±0.5, respectively and for eugenol, the haemaggulation titre showed a moderate increase with 112.06±6.169 and DTH 4.4±0.6, respectively. These differences were statistically significant. The essential oils were found to have a significant immunostimulant activity on both the specific and non-specific immune mechanisms.

  9. Immunomodulatory activity of geranial, geranial acetate, gingerol, and eugenol essential oils: evidence for humoral and cell-mediated responses

    Directory of Open Access Journals (Sweden)

    Seema Farhath

    2013-05-01

    Full Text Available Objective: The immunomodulatory effect of geranial, geranial acetate, gingerol, and eugenol essential oils were evaluated by studying humoral and cell-mediated immune responses. Materials and Method: The essential oils were evaluated for immunomodulatory activity in in vivo studies, using rats as the animal model. The essential oils were tested for hypersensitivity and hemagglutination reactions, using sheep red blood cells (SRBC as the antigen while sodium carboxy methyl cellulose (SCMC served as the control in all the tests. Result: Orally administrated essential oils showed a significant increase of test parameters, viz., haemagglutinating antibody titre (HAT and delayed type hypersensitivity (DTH response. In rats immunized with sheep RBC, essential oils enhanced the humoral antibody response to the antigen and significantly potentiated the cellular immunity by facilitating the foot pad thickness response to sheep RBC in sensitized rats with doses of 50-800 mg/ml. Haemagglutination titre of geraniol showed the highest increase of 139.3±6.38 and with 5.9±0.7 DTH, respectively. For geranial acetate, the haemagglutination titre showed a moderate increase of 87.5±5.9 and highest increase in DTH with 5.9±0.8, respectively. Using gingerol, the haemagglutination titre showed a moderate increase with 88.2±6.306 and DTH 3.5±0.5, respectively and for eugenol, the haemaggulation titre showed a moderate increase with 112.06±6.169 and DTH 4.4±0.6, respectively. These differences were statistically significant. Conclusion: The essential oils were found to have a significant immunostimulant activity on both the specific and non-specific immune mechanisms.

  10. Immunotoxicity of aflatoxin B1: Impairment of the cell-mediated response to vaccine antigen and modulation of cytokine expression

    International Nuclear Information System (INIS)

    Meissonnier, Guylaine M.; Pinton, Philippe; Laffitte, Joelle; Cossalter, Anne-Marie; Gong, Yun Yun; Wild, Christopher P.; Bertin, Gerard; Galtier, Pierre; Oswald, Isabelle P.

    2008-01-01

    Aflatoxin B1 (AFB1), a mycotoxin produced by Aspergillus flavus or A. parasiticus, is a frequent contaminant of food and feed. This toxin is hepatotoxic and immunotoxic. The present study analyzed in pigs the influence of AFB1 on humoral and cellular responses, and investigated whether the immunomodulation observed is produced through interference with cytokine expression. For 28 days, pigs were fed a control diet or a diet contaminated with 385, 867 or 1807 μg pure AFB1/kg feed. At days 4 and 15, pigs were vaccinated with ovalbumin. AFB1 exposure, confirmed by an observed dose-response in blood aflatoxin-albumin adduct, had no major effect on humoral immunity as measured by plasma concentrations of total IgA, IgG and IgM and of anti-ovalbumin IgG. Toxin exposure did not impair the mitogenic response of lymphocytes but delayed and decreased their specific proliferation in response to the vaccine antigen, suggesting impaired lymphocyte activation in pigs exposed to AFB1. The expression level of pro-inflammatory (TNF-α, IL-1β, IL-6, IFN-γ) and regulatory (IL-10) cytokines was assessed by real-time PCR in spleen. A significant up-regulation of all 5 cytokines was observed in spleen from pigs exposed to the highest dose of AFB1. In pigs exposed to the medium dose, IL-6 expression was increased and a trend towards increased IFN-γ and IL-10 was observed. In addition we demonstrate that IL-6 impaired in vitro the antigenic- but not the mitogenic-induced proliferation of lymphocytes from control pigs vaccinated with ovalbumin. These results indicate that AFB1 dietary exposure decreases cell-mediated immunity while inducing an inflammatory response. These impairments in the immune response could participate in failure of vaccination protocols and increased susceptibility to infections described in pigs exposed to AFB1

  11. A 17-year experience in perioperative anaphylaxis 1998-2015: harmonizing optimal detection of mast cell mediator release.

    Science.gov (United States)

    Egner, W; Sargur, R; Shrimpton, A; York, M; Green, K

    2016-11-01

    Sheffield NARCOS (National Adverse Reactions Advisory Service) investigates suspected perioperative anaesthetic reactions using serial tryptase, urinary methylhistamine (UMH) and clinical information. Further recommendations for additional allergy clinic assessment are provided. To establish a robustly measurable protocol for identifying mast cell mediator (MMR) release in this cohort. To compare these thresholds with previously suggested thresholds and algorithms. A review of 3455 NARCOS cases referred with a suspected perioperative allergic reaction. Tryptase, UMH and clinical details were analysed. A total of 1746 cases were graded using the Ring and Messmer scale. Reaction grade, tryptase and UMH changes were compared with statistical and graphical presentations appropriate to non-normally distributed measurements using Analyse-IT software. Sensitive strategies such as 3 μg/L or 20% are measurable and translatable and would substantially increase detection of potentially relevant changes in tryptases. Adequate quality assurance for low-level measurement is needed. An incremental threshold of 20% would identify potential MMR in an additional 14% of cases with peak tryptase (Tp) between 5 and 14 μg/L and a further 15% with Tp below 5 μg/L. Further work is required to establish the diagnostic performance characteristics of this more sensitive approach. UMH also identified up to 120 further cases of potential MMR in the absence of tryptase increments. Future studies should establish and compare the predictive performance characteristics of each strategy against clinical phenotypes. A single agreed definition of positive serial tryptases is needed to enable robust evaluation of diagnostic strategies. This could serve as a harmonized standard for comparative studies of case series from different centres. © 2016 John Wiley & Sons Ltd.

  12. Influence of Ganoderma lucidum (Curt.: Fr.) P. Karst. on T-cell-mediated immunity in normal and immunosuppressed mice line CBA/Ca.

    Science.gov (United States)

    Nizhenkovska, Iryna V; Pidchenko, Vitalii T; Bychkova, Nina G; Bisko, Nina A; Rodnichenko, Angela Y; Kozyko, Natalya O

    2015-09-01

    The article presents the results of the investigation of the effect of biomass powder of the fungus Ganoderma lucidum on T-cell-mediated immunity in normal and immunosuppressed mice CBA/Ca. Delayed-type hypersensitivity assay was used. Experimental immunodeficiency was established with intraperitoneal injection of the immunosuppressant cyclophosphamide at a single dose of 150 mg/kg on the first day of the experiment. Results of the study show that the administration of biomass powder of Ganoderma lucidum in a dose of 0.5 mg/kg orally for 10 days increases the delayed-type hypersensitivity response in normal mice CBA/Ca. Administration of 0.5 mg/kg of biomass powder of the fungus Ganoderma lucidum for 10 days blocked the development of the T-cell-mediated immunosuppression, induced by administration of cyclophosphamide and restored the delayed-type hypersensitivity response in immunosuppressed mice. Key words: fungus Ganoderma lucidum cyclophosphamide immunodeficiency T-cell-mediated immunity delayed-type hypersensitivity.

  13. Integrin αvβ8-Mediated TGF-β Activation by Effector Regulatory T Cells Is Essential for Suppression of T-Cell-Mediated Inflammation

    Science.gov (United States)

    Worthington, John J.; Kelly, Aoife; Smedley, Catherine; Bauché, David; Campbell, Simon; Marie, Julien C.; Travis, Mark A.

    2015-01-01

    Summary Regulatory T (Treg) cells play a pivotal role in suppressing self-harmful T cell responses, but how Treg cells mediate suppression to maintain immune homeostasis and limit responses during inflammation is unclear. Here we show that effector Treg cells express high amounts of the integrin αvβ8, which enables them to activate latent transforming growth factor-β (TGF-β). Treg-cell-specific deletion of integrin αvβ8 did not result in a spontaneous inflammatory phenotype, suggesting that this pathway is not important in Treg-cell-mediated maintenance of immune homeostasis. However, Treg cells lacking expression of integrin αvβ8 were unable to suppress pathogenic T cell responses during active inflammation. Thus, our results identify a mechanism by which Treg cells suppress exuberant immune responses, highlighting a key role for effector Treg-cell-mediated activation of latent TGF-β in suppression of self-harmful T cell responses during active inflammation. PMID:25979421

  14. 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.

  15. Evidence of cell-mediated cardiac myocyte injury involved in the heart failure of a patient with progressive systemic sclerosis.

    Science.gov (United States)

    Takahashi, N; Seko, Y; Azuma, M; Yagita, H; Okumura, K; Yazaki, Y

    1999-01-01

    A 54-year-old woman with progressive systemic sclerosis (PSS) was admitted to hospital because of dyspnea and chest pain. Echocardiogram revealed diffuse hypokinesis of the left ventricle (ejection fraction 24%). Methylprednisolone, heparin, and diuretics were administered, without benefit. Anemia, thrombocytopenia, and renal dysfunction rapidly progressed, and she died of heart failure on the 14th hospital day. Immunohistochemical study of the myocardial tissue showed mild to moderate cell infiltration, mainly consisting of natural killer (NK) cells, macrophages, cytotoxic T lymphocytes (CTLs), and T helper cells. Perforin, a cytolytic factor, was expressed in the infiltrating CTLs and NK cells, indicating that these cells were activated killer cells. Furthermore, human leukocyte antigen classes I and II, intercellular adhesion molecule-1, as well as costimulatory molecules B7-1, B7-2, and CD40, all of which are known not to be expressed in cardiac myocytes under normal conditions, were moderately to strongly expressed in cardiac myocytes. There was no detectable level of enterovirus genomes in the polymerase chain reaction products from the myocardial tissue of this patient. These findings strongly suggest that the infiltrating killer cells recognized cardiac myocytes as target cells and directly damaged them by releasing perforin. Enhanced expression of these antigens may have played an important role in the activation and cytotoxicity of the infiltrating killer cells. Absence of enterovirus genomes in the myocardial tissue may suggest that this autoimmune process is primarily induced by PSS.

  16. 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.

  17. Cytotoxicity of leukocytes from normal and Shigella-susceptible (opium-treated) guinea pigs against virulent Shigella sonnei.

    Science.gov (United States)

    Morgan, D R; DuPont, H L; Wood, L V; Kohl, S

    1984-01-01

    Intraepithelial lymphocytes were collected from the ileum of adult Hartley strain guinea pigs and used as effector cells in a 60-min bactericidal assay with virulent Shigella sonnei as target cells. Natural killer cytotoxicity (NKC) and antibody-dependent cellular cytotoxicity (ADCC) were measured and correlated with the resistance of the animals to infection by S. sonnei. Normal guinea pig intraepithelial lymphocytes exhibited mean NKC and ADCC values of 22.8 +/- 5.0 and 34.1 +/- 13.6, respectively. These animals were resistant to oral challenge with virulent S. sonnei. Intraepithelial lymphocytes from guinea pigs which were fasted for 4 days demonstrated NKC and ADCC values similar to those of normal animals (31.0 +/- 8.1 and 41.7 +/- 6.7, respectively). These animals also were resistant to oral challenge. Intraepithelial lymphocytes from guinea pigs which were given 1 ml of deodorized tincture of opium 2 h before cell collection demonstrated deficient NKC (4.7 +/- 4.2) and ADCC (5.3 +/- 4.9) values but remained resistant to infection by S. sonnei. When guinea pigs were fasted for 4 days and given opium, deficient NKC (2.0 +/- 2.0) and ADCC (1.3 +/- 1.3) values were demonstrated; this group of animals was susceptible to infection by S. sonnei (P less than 0.04). These experiments demonstrated that opium treatment depresses one form of gut immunity. When combined with starvation, opium treatment may increase susceptibility to infection by shigellae by modulation of immunity in addition to the effects on gut motility and bacterial flora. PMID:6384044

  18. 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.

  19. Enhancement Of The T Cell Mediated Hypersensitivity Reaction By Thymus Extract In GAMMA Irradiated BALB/C Mice

    International Nuclear Information System (INIS)

    EL-BEIH, N.M.; ESSAM, H.M.; MOHAMED, M.I.

    2009-01-01

    swelling response caused by gamma radiation. In conclusion, data of the present study showed a beneficial role of thymus extract in combating the negative effect of gamma irradiation on the T cell mediated hypersensitivity reaction.

  20. The cytotoxicity study of praziquantel enantiomers.

    Science.gov (United States)

    Sun, Qian; Mao, Ruifeng; Wang, Dongling; Hu, Changyan; Zheng, Yang; Sun, Dequn

    2016-01-01

    Praziquantel (PZQ) is prescribed as a racemic mixture (racemic-PZQ, rac-PZQ), which is composed of (R)-PZQ and (S)-PZQ. In this work, the cytotoxicity of rac-PZQ and its two enantiomers (R)-PZQ and (S)-PZQ on eight cell lines (L-02, HepG2, prf-plc-5, SH-SY5Y, HUVEC, A549, HCT-15, Raw264.7) was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphe-nyltetrazolium bromide and lactate dehydrogenase assays. The morphology of apoptotic cells was studied by fluorescence microscope using Hoechst 33342 staining, and the cytotoxicity of the compounds was also tested by lactate dehydrogenase assay. Results revealed that (R)-PZQ had negligible cytotoxicity against L-02, SH-SY5Y, HUVEC, A549, HCT-15, and Raw264.7 cells but selectively inhibited tumor cell lines (prf-plc-5 and HepG2). However, in contrast to (R)-PZQ, the (S)-isomer showed higher cytotoxicity against L-02 cells and lower inhibition on prf-plc-5 and HepG2 cells. Besides, (R)-PZQ showed lower cytotoxicity on SH-SY5Y cells than (S)-PZQ. Meanwhile, (R)-PZQ at cytotoxicity than (S)-PZQ and has similar cytotoxicity with rac-PZQ. (S)-PZQ is the principal enantiomer to cause side effects on human definitive hosts. These findings gave the reasonable reasons for World Health Organization to produce (R)-PZQ as a replacement for rac-PZQ for the treatment of schistosomiasis.

  1. In vitro cytotoxic, antiviral and immunomodulatory effects of Plantago major and Plantago asiatica.

    Science.gov (United States)

    Chiang, Lien-Chai; Chiang, Wen; Chang, Mei-Yin; Lin, Chun-Ching

    2003-01-01

    Plantago major linn. and P. asiatica Linn. (Plantaginaceae) are commonly used as folk medicine in Taiwan for treating infectious diseases related to the respiratory, urinary and digestive tracts. In this study, we investigated the antiviral, cytotoxic and immunomodulatory activities of hot water extracts of these two species in vitro on a series of viruses, namely herpesviruses (HSV-1 and HSV-2), adenoviruses (ADV-3, ADV-8 and ADV-11), and on various human leukemia, lymphoma and carcinoma cells with XTT, BrdU and IFN-gamma kits. Results showed that hot water extract of P. asiatica possessed significant inhibitory activity on the proliferation of lymphoma (U937) and carcinoma (bladder, bone, cervix, kidney, lung and stomach) cells and on viral infection (HSV-2 and ADV-11). P. major and P. asiatica both exhibited dual effects of immunodulatory activity, enhancing lymphocyte proliferation and secretion of interferon-gamma at low concentrations ( 50 microg/ml). The present study concludes that hot water extracts of P. major and P. asiatica possess abroad-spectrum of antileukemia, anticarcinoma and antiviral activities, as well as activities which modulate cell-mediated immunity. Further investigations to elucidate the active component(s) of P. asiatica and P. major and to evaluate their clinical application are warranted.

  2. Role of T-bet, the master regulator of Th1 cells, in the cytotoxicity of murine CD4+T cells.

    Science.gov (United States)

    Eshima, Koji; Misawa, Kana; Ohashi, Chihiro; Iwabuchi, Kazuya

    2018-03-25

    Although CD4 + T cells are generally regarded as helper T cells, some activated CD4 + T cells exert cytotoxicity. Since CD4 + cytotoxic T lymphocytes (CTLs) often secrete IFN-γ, CTL activity among CD4 + T cells may be attributable to Th1 cells, where a T-box family molecule, T-bet serves as the "master regulator". However, although the essential contribution of T-bet to the expression of IFN-γ has been well-documented, it remains unclear if T-bet is involved in CD4 + T cell-mediated cytotoxicity. In this study, in order to investigate the ability of T-bet to confer cytolytic activity on CD4 + T cells, we introduced the T-bet gene into non-cytocidal CD4 + T cell lines and analyzed their cytolytic function. We observed up-regulation of FasL (CD178) in T-bet-transfected CD4 + T cells, but not in untransfected parental cells, which provided the transfectant with cytotoxicity. In one cell line, T-bet transduction also induced perforin gene expression, and T-bet-transfectants efficiently killed Fas - target cells. Although T-bet repressed the up-regulation of CD40L (CD154), which controls FasL-mediated cytolysis, the level of CD40L expression on in vitro-differentiated Th1 cells was similar to that on Th2 cells, suggesting the existence of a compensatory mechanism. These results collectively indicate that T-bet may be involved in the expression of genes, such as FasL and perforin, that confer cytotoxicity on Th1 cells. © 2018 The Societies and John Wiley & Sons Australia, Ltd.

  3. 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.

  4. Safe handling of cytotoxics: guideline recommendations.

    Science.gov (United States)

    Easty, A C; Coakley, N; Cheng, R; Cividino, M; Savage, P; Tozer, R; White, R E

    2015-02-01

    This evidence-based practice guideline was developed to update and address new issues in the handling of cytotoxics, including the use of oral cytotoxics; the selection and use of personal protective equipment; and treatment in diverse settings, including the home setting. The guideline was developed primarily from an adaptation and endorsement of an existing guideline and from three systematic reviews. Before publication, the guideline underwent a series of peer and external reviews to gather feedback. All comments were addressed, and the guideline was amended when required. The guideline applies to health care workers who could come into contact with cytotoxic drugs at any point in the medication circuit. The intended users are hospital administrators, educators, and managers; occupational health and safety services; and pharmacy and health care workers. The recommendations represent a reasonable and practical set of procedures that the intended users of this guideline should implement to minimize opportunities for accidental exposure. They are not limited to just the point of care; they cover the entire chain of cytotoxics handling from the time such agents enter the institution until they leave in the patient or as waste. Reducing the likelihood of accidental exposure to cytotoxic agents within the medication circuit is the main objective of this evidenced-based guideline. The recommendations differ slightly from earlier guidelines because of the availability of new evidence.

  5. High-Throughput Flow Cytometric Method for the Simultaneous Measurement of CAR-T Cell Characterization and Cytotoxicity against Solid Tumor Cell Lines.

    Science.gov (United States)

    Martinez, Emily M; Klebanoff, Samuel D; Secrest, Stephanie; Romain, Gabrielle; Haile, Samuel T; Emtage, Peter C R; Gilbert, Amy E

    2018-04-01

    High-throughput flow cytometry is an attractive platform for the analysis of adoptive cellular therapies such as chimeric antigen receptor T cell therapy (CAR-T) because it allows for the concurrent measurement of T cell-dependent cellular cytotoxicity (TDCC) and the functional characterization of engineered T cells with respect to percentage of CAR transduction, T cell phenotype, and measurement of T cell function such as activation in a single assay. The use of adherent tumor cell lines can be challenging in these flow-based assays. Here, we present the development of a high-throughput flow-based assay to measure TDCC for a CAR-T construct co-cultured with multiple adherent tumor cell lines. We describe optimal assay conditions (such as adherent cell dissociation techniques to minimize impact on cell viability) that result in robust cytotoxicity assays. In addition, we report on the concurrent use of T cell transduction and activation antibody panels (CD25) that provide further dissection of engineered T cell function. In conclusion, we present the development of a high-throughput flow cytometry method allowing for in vitro interrogation of solid tumor, targeting CAR-T cell-mediated cytotoxicity, CAR transduction, and engineered T cell characterization in a single assay.

  6. 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.

  7. New cytotoxic phloroglucinol derivatives from Agrimonia pilosa.

    Science.gov (United States)

    Tang, Lan; Fu, Lulu; Lu, Chenghua; Hou, Xiaorong; Shan, Weiguang; Zhan, Zhajun

    2017-04-01

    Three new phloroglucinol derivatives, namely agripinol A-C (1-3), were isolated from Agrimonia pilosa Ledeb, along with two known ones (4-5). Their structures were characterized by spectroscopic methods, including MS and NMR spectroscopic techniques. The absolute configurations of the new compounds were unambiguously established by single crystal X-ray diffraction analyses. In the cytotoxicity assay, all compounds exhibited more potent cytotoxic activities against HCT-116, MDA-MB-231 and PC-3, as compared with the positive control fluorouracil. Copyright © 2017. Published by Elsevier B.V.

  8. Cytotoxicity of Two Triterpenoids from Nigella glandulifera

    Directory of Open Access Journals (Sweden)

    Erxi Wu

    2006-09-01

    Full Text Available During an investigation of antitumor substances from Nigella glandulifera Freyn et Sint. (Ranunculaceae the cytotoxicity of two oleanane triterpene saponins isolated from the seeds of this species, kalopanaxsaponins A and I, was evaluated against HepG2, drug resistant HepG2 (R-HepG2 (two hepatocyte cell lines and primary cultured normal mouse hepatocytes. Evident cytotoxic activities were observed. Morphological observations and cell cycle analysis suggest that these compounds inhibit the proliferation of hepatoma by inducing apoptosis and consequently kalopanaxsaponins A and I may be potential therapeutic agents for the treatment of parental and drug resistant hepatoma.

  9. Biotransformation and Cytotoxic Activity of Guaiacol Dimer

    Directory of Open Access Journals (Sweden)

    Galuh Widiyarti

    2014-07-01

    Full Text Available Guaiacol, a phenolic compound is known as an anticancer. Dimerization of guaiacol has been done by biotransformation using peroxidase enzyme as biocatalyst. This enzyme was isolated from Indonesian plant, kailan (Brassica oleraceae var. alboglabra. Analysis of dimerization product was carried out by TLC, IR, LC-MS, and NMR. Whilst analysis of in-vitro cytotoxic activity was carried out by MTT method against breast cancer T47D and MCF7 cells. The result showed that the dimerization reaction gave O-para dehydroguaiacol. The in-vitro cytotoxic activity analysis showed that O-para dehydroguaiacol compound has potency as anti-breast cancer.

  10. Cytotoxic Aaptamines from Malaysian Aaptos aaptos

    Directory of Open Access Journals (Sweden)

    Kee Cheng Ling

    2008-12-01

    Full Text Available In a preliminary screen, Aaptos aaptos showed significant cytotoxic activity towards a panel of cell lines and was thus subjected to bioassay-guided isolation of the bioactive constituents. In addition to the known aaptamine, two new derivatives of the alkaloid were isolated from the bioactive chloroform fraction of the crude methanolic extract. Detailed analysis by NMR and mass spectroscopy enabled their identification to be 3-(phenethylaminodemethyl(oxyaaptamine and 3-(isopentylaminodemethyl(oxy aaptamine. The cytotoxic activities of the three alkaloids were further evaluated against CEM-SS cells.

  11. IL-18 potentiated whole blood IFN-γ assay can identify cell-mediated immune responses towards Lawsonia intracellularis in experimentally infected pigs

    DEFF Research Database (Denmark)

    Riber, Ulla; Jakobsen, Jeanne Toft; Hvass, Henriette Cordes

    Lawsonia intracellularis is an obligate intracellular bacteria causing proliferative enteropathy (PE) in pigs. The infection causes diarrhoea, retarded growth and sudden death in pigs and is one of the most economically important diseases in the swine industry worldwide. The infection is one...... indications that cell-mediated immune responses (CMI) are important for the protection against infections with L. intracellularis and in mice models IFN-γ has been shown to play a key role in the host defence against experimental infections . In L. intracellularis infected pigs, IFN-γ is only sparsely...

  12. Cytotoxicity associated with prolonged room temperature storage of serum and proposed methods for reduction of cytotoxicity.

    Science.gov (United States)

    Shiraishi, Rikiya; Hirayama, Norio

    2015-12-01

    Canine serum preserved at room temperature (25°C) for longer than 24h is known to exhibit significant cytotoxicity. This phenomenon is one of the major reasons for the failure of virus neutralization tests. In this study, a method for reducing this cytotoxicity was investigated by applying several treatments to dog, cat and human serum prior to room temperature storage. Additionally, the identity of the cytotoxic factor generated during room temperature storage was investigated. Heat-inactivation at 56°C or 65°C and the addition of protease inhibitor prior to storage were found to be effective for reducing cytotoxicity in the serum. Furthermore, heat-inactivation at 65°C reduced the cytotoxicity that was induced under room temperature storage. Several protein factors in serum were suspected to play a role in the observed cytotoxicity. According to this study, the membrane-attack-complex in serum was not involved in the cytotoxicity. This study provides useful information for development and improvement of cell culture and virus neutralization tests. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Correlation between luminescence intensity and cytotoxicity in cell-based cytotoxicity assay using luciferase.

    Science.gov (United States)

    Wakuri, S; Yamakage, K; Kazuki, Y; Kazuki, K; Oshimura, M; Aburatani, S; Yasunaga, M; Nakajima, Y

    2017-04-01

    The luciferase reporter assay has become one of the conventional methods for cytotoxicity evaluation. Typically, the decrease of luminescence expressed by a constitutive promoter is used as an index of cytotoxicity. However, to our knowledge, there have been no reports of the correlation between cytotoxicity and luminescence intensity. In this study, to accurately verify the correlation between them, beetle luciferase was stably expressed in human hepatoma HepG2 cells harboring the multi-integrase mouse artificial chromosome vector. We showed that the cytotoxicity assay using luciferase does not depend on the stability of luciferase protein and the kind of constitutive promoter. Next, HepG2 cells in which green-emitting beetle luciferase was expressed under the control of CAG promoter were exposed to 58 compounds. The luminescence intensity and cytotoxicity curves of cells exposed to 48 compounds showed similar tendencies, whereas those of cells exposed to 10 compounds did not do so, although the curves gradually approached each other with increasing exposure time. Finally, we demonstrated that luciferase expressed under the control of a constitutive promoter can be utilized both as an internal control reporter for normalizing a test reporter and for monitoring cytotoxicity when two kinds of luciferases are simultaneously used in the cytotoxicity assay. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Incipient cytotoxicity: A time-independent measure of cytotoxic potency in vitro.

    Science.gov (United States)

    Gülden, Michael; Kähler, Daria; Seibert, Hasso

    2015-09-01

    Time is an important determinant of toxicity but largely ignored in in vitro toxicity assays where exposure times chosen are rather arbitrary. To investigate the impact of time on the cytotoxic potency of chemicals in vitro, the concentration dependent cytotoxic action of selected chemicals (surfactants, metals, oxidative stressors, a mitochondrial poison) was determined after various exposure times (1-72 h) in cultures of Balb/c 3T3 cells. Time affected the cytotoxic potency as well as the cytotoxic efficacy. The median cytotoxic concentrations, EC50, decreased and in most cases approached an "incipient" value, EC50,∞, within 72 h. Cytotoxicity due to mitochondrial insult occurred after a threshold time which was dependent on the medium glucose concentration. Within the chemicals studied the extent of potency change with time ranged from 3- to >1000-fold and the "time to incipient cytotoxicity", tic, from 4 to >72 h. Hence, also the relative cytotoxic potencies depend on exposure time. Ignoring this may lead to severe bias in toxicological hazard and risk assessment. Therefore it is recommended to determine the incipient cytotoxic potency of chemical compounds, represented by, e.g., the incipient median effect (EC50,∞), no effect (NEC∞) or lowest effect concentrations (LEC∞) instead of measures obtained after arbitrary exposure times. If this is not possible, the 72 h-potency measurements appear to be useful surrogates. These time-independent incipient potency values can be reasonably compared between substances, endpoints, cells and biological test systems and may serve to define points of departure for quantitative in vitro-in vivo extrapolations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. The Human Antibody Fragment DIATHIS1 Specific for CEACAM1 Enhances Natural Killer Cell Cytotoxicity Against Melanoma Cell Lines In Vitro

    Science.gov (United States)

    Dupuis, Maria L.; Soriani, Alessandra; Ricci, Biancamaria; Dominici, Sabrina; Moricoli, Diego; Ascione, Alessandro; Santoni, Angela; Magnani, Mauro; Cianfriglia, Maurizio

    2015-01-01

    Several lines of evidence show that de novo expression of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is strongly associated with reduced disease-free survival of patients affected by metastatic melanoma. Previously published investigations report that homophilic interactions between CEACAM1 expressed on natural killer (NK) cells and tumors inhibit the NK cell-mediated killing independently of major histocompatibility complex class I recognition. This biological property can be physiologically relevant in metastatic melanoma because of the increased CEACAM1 expression observed on NK cells from some patients. Moreover, this inhibitory mechanism in many cases might hinder the efficacy of immunotherapeutic treatments of CEACAM1+ malignancies because of tumor evasion by activated effector cells. In the present study, we designed an in vitro experimental model showing that the human single-chain variable fragment (scFv) DIATHIS1 specific for CEACAM1 is able to enhance the lytic machinery of NK cells against CEACAM1+ melanoma cells. The coincubation of the scFv DIATHIS1 with CEACAM1+ melanoma cells and NK-92 cell line significantly increases the cell-mediated cytotoxicity. Moreover, pretreatment of melanoma cells with scFv DIATHIS1 promotes the activation and the degranulation capacity of in vitro–expanded NK cells from healthy donors. It is interesting to note that the melanoma cell line MelC and the primary melanoma cells STA that respond better to DIATHIS1 treatment, express higher relative levels of CEACAM1-3L and CEACAM1-3S splice variants isoforms compared with Mel501 cells that are less responsive to DIATHIS1-induced NK cell–mediated cytotoxicity. Taken together, our results suggest that the fully human antibody fragment DIATHIS1 originated by biopanning approach from a phage antibody library may represent a relevant biotechnological platform to design and develop completely human antimelanoma therapeutics of biological origin. PMID

  16. The Escape of Cancer from T Cell-Mediated Immune Surveillance: HLA Class I Loss and Tumor Tissue Architecture

    Directory of Open Access Journals (Sweden)

    Federico Garrido

    2017-02-01

    Full Text Available Tumor immune escape is associated with the loss of tumor HLA class I (HLA-I expression commonly found in malignant cells. Accumulating evidence suggests that the efficacy of immunotherapy depends on the expression levels of HLA class I molecules on tumors cells. It also depends on the molecular mechanism underlying the loss of HLA expression, which could be reversible/“soft” or irreversible/“hard” due to genetic alterations in HLA, β2-microglobulin or IFN genes. Immune selection of HLA-I negative tumor cells harboring structural/irreversible alterations has been demonstrated after immunotherapy in cancer patients and in experimental cancer models. Here, we summarize recent findings indicating that tumor HLA-I loss also correlates with a reduced intra-tumor T cell infiltration and with a specific reorganization of tumor tissue. T cell immune selection of HLA-I negative tumors results in a clear separation between the stroma and the tumor parenchyma with leucocytes, macrophages and other mononuclear cells restrained outside the tumor mass. Better understanding of the structural and functional changes taking place in the tumor microenvironment may help to overcome cancer immune escape and improve the efficacy of different immunotherapeutic strategies. We also underline the urgent need for designing strategies to enhance tumor HLA class I expression that could improve tumor rejection by cytotoxic T-lymphocytes (CTL.

  17. HPV-E7 Delivered by Engineered Exosomes Elicits a Protective CD8+ T Cell-Mediated Immune Response

    Science.gov (United States)

    Di Bonito, Paola; Ridolfi, Barbara; Columba-Cabezas, Sandra; Giovannelli, Andrea; Chiozzini, Chiara; Manfredi, Francesco; Anticoli, Simona; Arenaccio, Claudia; Federico, Maurizio

    2015-01-01

    We developed an innovative strategy to induce a cytotoxic T cell (CTL) immune response against protein antigens of choice. It relies on the production of exosomes, i.e., nanovesicles spontaneously released by all cell types. We engineered the upload of huge amounts of protein antigens upon fusion with an anchoring protein (i.e., HIV-1 Nefmut), which is an inactive protein incorporating in exosomes at high levels also when fused with foreign proteins. We compared the immunogenicity of engineered exosomes uploading human papillomavirus (HPV)-E7 with that of lentiviral virus-like particles (VLPs) incorporating equivalent amounts of the same antigen. These exosomes, whose limiting membrane was decorated with VSV-G, i.e., an envelope protein inducing pH-dependent endosomal fusion, proved to be as immunogenic as the cognate VLPs. It is noteworthy that the immunogenicity of the engineered exosomes remained unaltered in the absence of VSV-G. Most important, we provide evidence that the inoculation in mouse of exosomes uploading HPV-E7 induces production of anti-HPV E7 CTLs, blocks the growth of syngeneic tumor cells inoculated after immunization, and controls the development of tumor cells inoculated before the exosome challenge. These results represent the proof-of-concept about both feasibility and efficacy of the Nefmut-based exosome platform for the induction of CD8+ T cell immunity. PMID:25760140

  18. HPV-E7 Delivered by Engineered Exosomes Elicits a Protective CD8+ T Cell-Mediated Immune Response

    Directory of Open Access Journals (Sweden)

    Paola Di Bonito

    2015-03-01

    Full Text Available We developed an innovative strategy to induce a cytotoxic T cell (CTL immune response against protein antigens of choice. It relies on the production of exosomes, i.e., nanovesicles spontaneously released by all cell types. We engineered the upload of huge amounts of protein antigens upon fusion with an anchoring protein (i.e., HIV-1 Nefmut, which is an inactive protein incorporating in exosomes at high levels also when fused with foreign proteins. We compared the immunogenicity of engineered exosomes uploading human papillomavirus (HPV-E7 with that of lentiviral virus-like particles (VLPs incorporating equivalent amounts of the same antigen. These exosomes, whose limiting membrane was decorated with VSV-G, i.e., an envelope protein inducing pH-dependent endosomal fusion, proved to be as immunogenic as the cognate VLPs. It is noteworthy that the immunogenicity of the engineered exosomes remained unaltered in the absence of VSV-G. Most important, we provide evidence that the inoculation in mouse of exosomes uploading HPV-E7 induces production of anti-HPV E7 CTLs, blocks the growth of syngeneic tumor cells inoculated after immunization, and controls the development of tumor cells inoculated before the exosome challenge. These results represent the proof-of-concept about both feasibility and efficacy of the Nefmut-based exosome platform for the induction of CD8+ T cell immunity.

  19. Induction of foetal haemoglobin synthesis in erythroid progenitor stem cells: mediated by water-soluble components of Terminalia catappa.

    Science.gov (United States)

    Aimola, I A; Inuwa, H M; Nok, A J; Mamman, A I

    2014-06-01

    Current novel therapeutic agents for the treatment of sickle cell anaemia (SCA) focus on increasing foetal haemoglobin (HbF) levels in SCA patients. Unfortunately, the only approved HbF-inducing agent, hydroxyurea, has long-term unpredictable side effects. Studies have shown the potential of plant compounds to modulate HbF synthesis in primary erythroid progenitor stem cells. We isolated a novel HbF-inducing Terminalia catappa distilled water active fraction (TCDWF) from Terminalia catappa leaves that induced the commitment of erythroid progenitor stem cells to the erythroid lineage and relatively higher HbF synthesis of 9.2- and 6.8-fold increases in both erythropoietin (EPO)-independent and EPO-dependent progenitor stem cells respectively. TCDWF was differentially cytotoxic to EPO-dependent and EPO-independent erythroid progenitor stem cell cultures as revealed by lactate dehydrogenase release from the cells. TCDWF demonstrated a protective effect on EPO-dependent and not EPO-independent progenitor cells. TCDWF induced a modest increase in caspase 3 activity in EPO-independent erythroid progenitor stem cell cultures compared with a significantly higher (P˂0.05) caspase 3 activity in EPO-dependent ones. The results demonstrate that TCDWF may hold promising HbF-inducing compounds, which work synergistically, and suggest a dual modulatory effect on erythropoiesis inherent in this active fraction. Copyright © 2014 John Wiley & Sons, Ltd.

  20. IFN-α-producing PDCA-1+ Siglec-H- B cells mediate innate immune defense by activating NK cells.

    Science.gov (United States)

    Bao, Yan; Han, Yanmei; Chen, Zhubo; Xu, Sheng; Cao, Xuetao

    2011-03-01

    B cells have multiple functions in adaptive immunity, including antibody production, antigen presentation and regulation of T-cell responses. Recent evidences indicate that B cells have more subsets than previously thought and may have non-classical functions, such as involvement in innate immunity and immune regulation; however, how B cells respond to microbial infection and elicit innate defense remain unclear. In this study, we identified a new subset of PDCA-1(+) Siglec-H(-) CD19(+) B cells in mice during the early period of bacterial infection with Listeria monocytogenes. PDCA-1(+) Siglec-H(-) CD19(+) B cells secreted large amounts of IFN-α and thus facilitated IFN-γ production and cytotoxicity function of natural killer (NK) cells via IFN-α. B-cell-deficient Btk(-/-) mice were incapable of producing PDCA-1(+) CD19(+) B cells, and were more sensitive to L. monocytogenes infection. Adoptive transfer of PDCA-1(+) CD19(+) B cells to Btk(-/-) mice normalized their resistance to L. monocytogenes infection. Furthermore, we found that macrophages were essential for the inducible generation of PDCA-1(+) Siglec-H(-) CD19(+) B cells via CD40-CD40L ligation. Therefore, we have identified a new subset of PDCA-1(+) Siglec-H(-) CD19(+) B cells, which enhances innate immune responses against bacterial infection by activating NK cells via secretion of IFN-α. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. Phytochemical and cytotoxic analysis of Pharthenium hysterophosis ...

    African Journals Online (AJOL)

    Parthenium hysterophorus is a well known medicinal plant widely used traditionally in the treatment of various diseases and as a constituent of various drugs, and in phytotherapy. The current study was designed to investigate the phytochemical screening and cytotoxic capacity of methanolic and n-hexane extract of P.

  6. Synthesis and cytotoxic evaluation of isoxazoles an

    Indian Academy of Sciences (India)

    tetrazolium bromide] cell proliferation assay was used to evaluate the cytotoxic activity of the synthesized compounds against COLO320 adenocarcinoma col- orectal cancer cell lines.6 COLO320 cancer cell line was maintained in complete tissue culture medium. RPMI with 10% Fetal Bovine Serum and 2 mM L-. Glutamine ...

  7. 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, ...

  8. Anticonvulsant, Antimicrobial and Cytotoxic Activities of Berberis ...

    African Journals Online (AJOL)

    Purpose: To evaluate the anticonvulsant, antimicrobial and cytotoxic activities of Berberis calliobotrys. Methods: The powdered plant material (10 kg) was extracted thrice with methanol (3 × 12 L) by dipping for seven days. The methanol extract was concentrated to dryness under reduced pressure, and then successively ...

  9. 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 ...

  10. 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 ...

  11. Synthesis, characterisation, nuclease and cytotoxic activity of ...

    Indian Academy of Sciences (India)

    GULZAR A BHAT

    2018-02-07

    Feb 7, 2018 ... Synthesis, characterisation, nuclease and cytotoxic activity of phosphate-free and phosphate-containing copper. 4 -(N-methylpyridinium)-2,2 :6 ,2 terpyridine complexes. GULZAR A BHATa, RAIHANA MAQBOOLb and RAMASWAMY MURUGAVELa,∗. aDepartment of Chemistry, Indian Institute of ...

  12. Rifampicin: Cytotoxic and Genotoxic Action | Olufunsho | Nigerian ...

    African Journals Online (AJOL)

    The purpose of this study was to investigate the cytotoxic and genotoxic effects of Rif to better understand its mutagenicity. The study was carried out using three methods: Standard Allium cepa (Linn.) assay, modified Ames test (which is a modification of the standard Ames assay) and micronucleus test (an in vivo method ...

  13. 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.

  14. 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 ...

  15. Fowlpox virus recombinants expressing HPV-16 E6 and E7 oncogenes for the therapy of cervical carcinoma elicit humoral and cell-mediated responses in rabbits.

    Science.gov (United States)

    Radaelli, Antonia; Pozzi, Eleana; Pacchioni, Sole; Zanotto, Carlo; Morghen, Carlo De Giuli

    2010-04-21

    Around half million new cases of cervical cancer arise each year, making the development of an effective therapeutic vaccine against HPV a high priority. As the E6 and E7 oncoproteins are expressed in all HPV-16 tumour cells, vaccines expressing these proteins might clear an already established tumour and support the treatment of HPV-related precancerous lesions. Three different immunisation regimens were tested in a pre-clinical trial in rabbits to evaluate the humoral and cell-mediated responses of a putative HPV-16 vaccine. Fowlpoxvirus (FP) recombinants separately expressing the HPV-16 E6 (FPE6) and E7 (FPE7) transgenes were used for priming, followed by E7 protein boosting. All of the protocols were effective in eliciting a high antibody response. This was also confirmed by interleukin-4 production, which increased after simultaneous priming with both FPE6 and FPE7 and after E7 protein boost. A cell-mediated immune response was also detected in most of the animals. These results establish a preliminary profile for the therapy with the combined use of avipox recombinants, which may represent safer immunogens than vaccinia-based vectors in immuno-compromised individuals, as they express the transgenes in most mammalian cells in the absence of a productive replication.

  16. Fowlpox virus recombinants expressing HPV-16 E6 and E7 oncogenes for the therapy of cervical carcinoma elicit humoral and cell-mediated responses in rabbits

    Directory of Open Access Journals (Sweden)

    Pacchioni Sole

    2010-04-01

    Full Text Available Abstract Background Around half million new cases of cervical cancer arise each year, making the development of an effective therapeutic vaccine against HPV a high priority. As the E6 and E7 oncoproteins are expressed in all HPV-16 tumour cells, vaccines expressing these proteins might clear an already established tumour and support the treatment of HPV-related precancerous lesions. Methods Three different immunisation regimens were tested in a pre-clinical trial in rabbits to evaluate the humoral and cell-mediated responses of a putative HPV-16 vaccine. Fowlpoxvirus (FP recombinants separately expressing the HPV-16 E6 (FPE6 and E7 (FPE7 transgenes were used for priming, followed by E7 protein boosting. Results All of the protocols were effective in eliciting a high antibody response. This was also confirmed by interleukin-4 production, which increased after simultaneous priming with both FPE6 and FPE7 and after E7 protein boost. A cell-mediated immune response was also detected in most of the animals. Conclusion These results establish a preliminary profile for the therapy with the combined use of avipox recombinants, which may represent safer immunogens than vaccinia-based vectors in immuno-compromised individuals, as they express the transgenes in most mammalian cells in the absence of a productive replication.

  17. 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.

  18. Radiation vulcanized natural rubber latex is not cytotoxic

    International Nuclear Information System (INIS)

    Nakamura, Akitada; Ikarashi, Y.; Tsuchiya, T.; Kaniwa, M.

    1990-01-01

    It has been reported that urethritis and/or urethral strictures caused by urinary catheters relates to cytotoxicities of their materials, and that natural rubber latex (NRL) materials often show the strong cytotoxicities. This paper reports the cytotoxicity testing method using chinese hamster V79 cultured cells, clarifies that the toxicities of NRLs vulcanized by the conventional processes are due mainly to the contents of zinc dialkyldithiocarbamates in the materials, and that the cytotoxicity of radiation vulcanized NRL (RVNRL) is very weak. (author)

  19. Cytotoxic hydroazulene diterpenes from the brown alga Cystoseira myrica.

    Science.gov (United States)

    Ayyad, Seif-Eldin N; Abdel-Halim, Osama B; Shier, W Thomas; Hoye, Thomas R

    2003-01-01

    Cytotoxicity-guided fractionation of the alcohol extract of the brown alga, Cystoseira myrica, afforded four new cytotoxic hydroazulene diterpenes, dictyone acetate (2), dictyol F monoacetate (4), isodictytriol monoacetate (6), and cystoseirol monoacetate (8), together with two known cytotoxic hydroazulene diterpenes, pachydictyol A (1) and dictyone (3). The constitution of each isolated compound has been determined on the basis of spectroscopic and chemical evidence.

  20. 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 ...

  1. CYTOTOXICITY TESTING OF WOUND DRESSINGS USING METHYLCELLULOSE CELL-CULTURE

    NARCIS (Netherlands)

    VANLUYN, MJA; VANWACHEM, PB; NIEUWENHUIS, P; JONKMAN, MF

    1992-01-01

    Wound dressings may induce cytotoxic effects. In this study, we check several, mostly commercially available, wound dressings for cytotoxicity. We used our previously described, newly developed and highly sensitive 7 d methylcellulose cell culture with fibroblasts as the test system. Cytotoxicity is

  2. Altered features and increased chemosensitivity of human breast cancer cells mediated by adipose tissue-derived mesenchymal stromal cells.

    Science.gov (United States)

    Kucerova, Lucia; Skolekova, Svetlana; Matuskova, Miroslava; Bohac, Martin; Kozovska, Zuzana

    2013-11-09

    Mesenchymal stromal cells (MSCs) represent heterogeneous cell population suitable for cell therapies in regenerative medicine. MSCs can also substantially affect tumor biology due to their ability to be recruited to the tumor stroma and interact with malignant cells via direct contacts and paracrine signaling. The aim of our study was to characterize molecular changes dictated by adipose tissue-derived mesenchymal stromal cells (AT-MSCs) and the effects on drug responses in human breast cancer cells SKBR3. The tumor cells were either directly cocultured with AT-MSCs or exposed to MSCs-conditioned medium (MSC-CM). Changes in cell biology were evaluated by kinetic live cell imaging, fluorescent microscopy, scratch wound assay, expression analysis, cytokine secretion profiling, ATP-based viability and apoptosis assays. The efficiency of cytotoxic treatment in the presence of AT-MSCs or MSCs-CM was analyzed. The AT-MSCs altered tumor cell morphology, induced epithelial-to-mesenchymal transition, increased mammosphere formation, cell confluence and migration of SKBR3. These features were attributed to molecular changes induced by MSCs-secreted cytokines and chemokines in breast cancer cells. AT-MSCs significantly inhibited the proliferation of SKBR3 cells in direct cocultures which was shown to be dependent on the SDF-1α/CXCR4 signaling axis. MSC-CM-exposed SKBR3 or SKBR3 in direct coculture with AT-MSCs exhibited increased chemosensitivity and induction of apoptosis in response to doxorubicin and 5-fluorouracil. Our work further highlights the multi-level nature of tumor-stromal cell interplay and demonstrates the capability of AT-MSCs and MSC-secreted factors to alter the anti-tumor drug responses.

  3. CD8 T cell-mediated killing of orexinergic neurons induces a narcolepsy-like phenotype in mice.

    Science.gov (United States)

    Bernard-Valnet, Raphaël; Yshii, Lidia; Quériault, Clémence; Nguyen, Xuan-Hung; Arthaud, Sébastien; Rodrigues, Magda; Canivet, Astrid; Morel, Anne-Laure; Matthys, Arthur; Bauer, Jan; Pignolet, Béatrice; Dauvilliers, Yves; Peyron, Christelle; Liblau, Roland S

    2016-09-27

    Narcolepsy with cataplexy is a rare and severe sleep disorder caused by the destruction of orexinergic neurons in the lateral hypothalamus. The genetic and environmental factors associated with narcolepsy, together with serologic data, collectively point to an autoimmune origin. The current animal models of narcolepsy, based on either disruption of the orexinergic neurotransmission or neurons, do not allow study of the potential autoimmune etiology. Here, we sought to generate a mouse model that allows deciphering of the immune mechanisms leading to orexin(+) neuron loss and narcolepsy development. We generated mice expressing the hemagglutinin (HA) as a "neo-self-antigen" specifically in hypothalamic orexin(+) neurons (called Orex-HA), which were transferred with effector neo-self-antigen-specific T cells to assess whether an autoimmune process could be at play in narcolepsy. Given the tight association of narcolepsy with the human leukocyte antigen (HLA) HLA-DQB1*06:02 allele, we first tested the pathogenic contribution of CD4 Th1 cells. Although these T cells readily infiltrated the hypothalamus and triggered local inflammation, they did not elicit the loss of orexin(+) neurons or clinical manifestations of narcolepsy. In contrast, the transfer of cytotoxic CD8 T cells (CTLs) led to both T-cell infiltration and specific destruction of orexin(+) neurons. This phenotype was further aggravated upon repeated injections of CTLs. In situ, CTLs interacted directly with MHC class I-expressing orexin(+) neurons, resulting in cytolytic granule polarization toward neurons. Finally, drastic neuronal loss caused manifestations mimicking human narcolepsy, such as cataplexy and sleep attacks. This work demonstrates the potential role of CTLs as final effectors of the immunopathological process in narcolepsy.

  4. Nature of the suppressor cells mediating prolonged graft survival after administration of extracted histocompatibility antigen and cyclosporine

    International Nuclear Information System (INIS)

    Yoshimura, N.; Kahan, B.D.

    1985-01-01

    Antigen-specific suppressor T cells are induced by donor histocompatibility antigen extracted from spleen cells with 3M KCl combined with cyclosporine (Ag-CsA). A single i.v. injection of 5 mg 3M-KCl-extracted donor Buffalo (Buf, RT1b) antigen (Ag) combined with a three day course of CsA prolonged renal allograft survival in Wistar-Furth (WFu, RT1u) hosts to a greater extent (MST 26.5 days) than CsA alone (MST 11.8 days). Peripheral blood lymphocytes (PBL) or spleen cells harvested from Ag-CsA-treated recipients ten days after transplantation inhibited the mixed lymphocyte reaction (MLR) between normal responder WFu cells and irradiated Buf cells (55.6% and 64.4% suppression, respectively, P less than 0.025), but not third-party Brown-Norway (BN, RT1n) stimulator cells (13.6% and -18.3% suppression, respectively, NS). The suppressor effect was not mediated by cytolytic cells; there was neither primary nor secondary cytolytic activity against 51 Cr-labeled Con-A blastoid Buf cells. The suppressor cells were neither adherent to plastic dishes nor to nylon-wool columns. PBL irradiated with 800 rads, but not 1500 rads, suppressed the MLR. A single injection of cyclophosphamide (CY, 25 mg/kg) seven days after transplantation abrogated the suppression induced by Ag-CsA treatment. Moreover, PBL from Ag-CsA recipients failed to suppress the MLR, if depleted either of all T cells by treatment with monoclonal antibody (Mab) W3/13 HLK (pan T cells; % suppression -15.8), or of cytotoxic/suppressor cells with Mab OX-8 (-19.3% suppression) together with rabbit antimouse immunoglobulin and complement

  5. Altered features and increased chemosensitivity of human breast cancer cells mediated by adipose tissue-derived mesenchymal stromal cells

    International Nuclear Information System (INIS)

    Kucerova, Lucia; Skolekova, Svetlana; Matuskova, Miroslava; Bohac, Martin; Kozovska, Zuzana

    2013-01-01

    Mesenchymal stromal cells (MSCs) represent heterogeneous cell population suitable for cell therapies in regenerative medicine. MSCs can also substantially affect tumor biology due to their ability to be recruited to the tumor stroma and interact with malignant cells via direct contacts and paracrine signaling. The aim of our study was to characterize molecular changes dictated by adipose tissue-derived mesenchymal stromal cells (AT-MSCs) and the effects on drug responses in human breast cancer cells SKBR3. The tumor cells were either directly cocultured with AT-MSCs or exposed to MSCs-conditioned medium (MSC-CM). Changes in cell biology were evaluated by kinetic live cell imaging, fluorescent microscopy, scratch wound assay, expression analysis, cytokine secretion profiling, ATP-based viability and apoptosis assays. The efficiency of cytotoxic treatment in the presence of AT-MSCs or MSCs-CM was analyzed. The AT-MSCs altered tumor cell morphology, induced epithelial-to-mesenchymal transition, increased mammosphere formation, cell confluence and migration of SKBR3. These features were attributed to molecular changes induced by MSCs-secreted cytokines and chemokines in breast cancer cells. AT-MSCs significantly inhibited the proliferation of SKBR3 cells in direct cocultures which was shown to be dependent on the SDF-1α/CXCR4 signaling axis. MSC-CM-exposed SKBR3 or SKBR3 in direct coculture with AT-MSCs exhibited increased chemosensitivity and induction of apoptosis in response to doxorubicin and 5-fluorouracil. Our work further highlights the multi-level nature of tumor-stromal cell interplay and demonstrates the capability of AT-MSCs and MSC-secreted factors to alter the anti-tumor drug responses

  6. Inhibition of allogeneic cytotoxic T cell (CD8+) proliferation via polymer-induced Treg (CD4+) cells.

    Science.gov (United States)

    Kang, Ning; Toyofuku, Wendy M; Yang, Xining; Scott, Mark D

    2017-07-15

    T cell-mediated immune rejection remains a barrier to successful transplantation. Polymer-based bioengineering of cells may provide an effective means of preventing allorecognition and the proliferation of cytotoxic (CD8 + ) T lymphocytes (CTL). Using MHC-disparate murine splenocytes modified with succinimidyl valerate activated methoxypoly(ethylene glycol) [SVA-mPEG] polymers, the effects of leukocyte immunocamouflage on CD8 + and CD4 + alloproliferation and T regulatory (Treg) cell induction were assessed in a mixed lymphocyte reaction (MLR) model. Polymer-grafting effectively camouflaged multiple leukocyte markers (MHC class I and II, TCR and CD3) essential for effective allorecognition. Consequent to the polymer-induced immunocamouflage of the cell membrane, both CD8 + and CD4 + T cell alloproliferation were significantly inhibited in a polymer dose-dependent manner. The loss of alloproliferation correlated with the induction of Treg cells (CD4 + CD25 + Foxp3 + ). The Tregs, surprisingly, arose primarily via differentiation of naive, non-proliferating, CD4 + cells. Of biologic importance, the polymer-induced Treg were functional and exhibited potent immunosuppressive activity on allogeneic CTL proliferation. These results suggest that immunocamouflage-mediated attenuation of alloantigen-TCR recognition can prevent the tissue destructive allogeneic CD8 + T cell response, both directly and indirectly, through the generation/differentiation of functional Tregs. Immunocamouflage induced tolerance could be clinically valuable in attenuating T cell-mediated transplant rejection and in the treatment of autoimmune diseases. While our previous studies have demonstrated that polymer-grafting to MHC disparate leukocytes inhibits CD4 + cell proliferation, the effects of PEGylation on the alloproliferation of CD8 + cytotoxic T cells (CTL) was not examined. As shown here, PEGylation of allogeneic leukocytes prevents the generation of the CTL response responsible for acute

  7. Cord blood stem cell-mediated induction of apoptosis in glioma downregulates X-linked inhibitor of apoptosis protein (XIAP.

    Directory of Open Access Journals (Sweden)

    Venkata Ramesh Dasari

    2010-07-01

    Full Text Available XIAP (X-linked inhibitor of apoptosis protein is one of the most important members of the apoptosis inhibitor family. XIAP is upregulated in various malignancies, including human glioblastoma. It promotes invasion, metastasis, growth and survival of malignant cells. We hypothesized that downregulation of XIAP by human umbilical cord blood mesenchymal stem cells (hUCBSC in glioma cells would cause them to undergo apoptotic death.We observed the effect of hUCBSC on two malignant glioma cell lines (SNB19 and U251 and two glioma xenograft cell lines (4910 and 5310. In co-cultures of glioma cells with hUCBSC, proliferation of glioma cells was significantly inhibited. This is associated with increased cytotoxicity of glioma cells, which led to glioma cell death. Stem cells induced apoptosis in glioma cells, which was evaluated by TUNEL assay, FACS analyses and immunoblotting. The induction of apoptosis is associated with inhibition of XIAP in co-cultures of hUCBSC. Similar results were obtained by the treatment of glioma cells with shRNA to downregulate XIAP (siXIAP. Downregulation of XIAP resulted in activation of caspase-3 and caspase-9 to trigger apoptosis in glioma cells. Apoptosis is characterized by the loss of mitochondrial membrane potential and upregulation of mitochondrial apoptotic proteins Bax and Bad. Cell death of glioma cells was marked by downregulation of Akt and phospho-Akt molecules. We observed similar results under in vivo conditions in U251- and 5310-injected nude mice brains, which were treated with hUCBSC. Under in vivo conditions, Smac/DIABLO was found to be colocalized in the nucleus, showing that hUCBSC induced apoptosis is mediated by inhibition of XIAP and activation of Smac/DIABLO.Our results indicate that downregulation of XIAP by hUCBSC treatment induces apoptosis, which led to the death of the glioma cells and xenograft cells. This study demonstrates the therapeutic potential of XIAP and hUCBSC to treat malignant

  8. 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.

  9. Improved cytotoxicity testing of magnesium materials

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Janine, E-mail: janine.fischer@hzg.de [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.

  10. Increase of cytotoxicity during wastewater chlorination: Impact factors and surrogates.

    Science.gov (United States)

    Du, Ye; Wu, Qian-Yuan; Lu, Yun; Hu, Hong-Ying; Yang, Yang; Liu, Rui; Liu, Feng

    2017-02-15

    Toxic and harmful disinfection byproducts (DBPs) were formed during wastewater chlorination. It was recently suggested that cytotoxicity to mammalian cells reflects risks posed by chlorinated wastewater. Here, ATP assays were performed to evaluate the cytotoxicity to mammalian cells. Chlorination significantly increased cytotoxicity of treated wastewater. Factors affecting cytotoxicity formation during wastewater chlorination were investigated. Quenching with sodium thiosulfate and ascorbic acid decreased the formed cytotoxicity, while ammonium kept the cytotoxicity stable. The chlorine dose required for the maximum cytotoxicity increase was dramatically affected by DOC and ammonia concentrations. The maximum cytotoxicity increase, defined as the cytotoxicity formation potential (CtFP), occurred when wastewater was treated for 48h with a chlorine dose of 2·DOC+11·NH 3 N+10 (mg-Cl 2 /L). During chlorination, the amounts of AOX formation was found to be significantly correlated with cytotoxicity formation when no DBPs were destroyed. AOX formation could be used as a surrogate to estimate cytotoxicity increase during wastewater chlorination. Besides, the CtFP of 14 treated wastewater samples was assessed ranged from 5.4-20.4mg-phenol/L. The CtFP could be estimated from UV 254 of treated wastewater because CtFP and UV 254 were strongly correlated. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Multifunctional cytotoxic agents from Anacardium occidentale.

    Science.gov (United States)

    Kubo, Isao; Nitoda, Teruhiko; Tocoli, Felismino E; Green, Ivan R

    2011-01-01

    The effects of anacardic acids and cardols isolated from the cashew nut and apple Anacardium occidentale (Anacardiaceae) on murine B16-F10 melanoma cells were tested. Although anacardic acids and cardols were found to inhibit tyrosinase, a key enzyme in melanin synthesis, melanogenesis in melanocytes was not suppressed in cultured cells but rather enhanced. Both anacardic acids and cardols exhibited moderate cytotoxicity. Copyright © 2010 John Wiley & Sons, Ltd.

  12. Arecoline is cytotoxic for human endothelial cells.

    Science.gov (United States)

    Ullah, Mafaz; Cox, Stephen; Kelly, Elizabeth; Boadle, Ross; Zoellner, Hans

    2014-11-01

    Oral submucous fibrosis is a pre-malignant fibrotic condition caused by areca nut use and involves reduced mucosal vascularity. Arecoline is the principal areca nut alkaloid and is cytotoxic for epithelium and fibroblasts. Endothelial cell cycle arrest is reported on exposure to arecoline, as is cytotoxicity for endothelial-lung carcinoma hybrid cells. We here describe cytotoxicity for primary human endothelial cultures from seven separate donors. Human umbilical vein endothelial cells were exposed to increasing concentrations of arecoline and examined by: phase-contrast microscopy, haemocytometer counts, transmission electron microscopy, lactate dehydrogenase release and the methyl-thiazol-tetrazolium assay. Vacuolation and detachment of endothelium were observed at and above arecoline concentrations of 333 μg/ml or more. Ultrastructural features of cellular stress were seen after 24-h treatment with 111 μg/ml arecoline and included reduced ribosomal studding of endoplasmic reticulum, increased autophagolysosomal structures, increased vacuolation and reduced mitochondrial cristae with slight swelling. Similar changes were seen at 4 h with arecoline at 333 μg/ml or above, but with more severe mitochondrial changes including increased electron density of mitochondrial matrix and greater cristal swelling, while by 24 h, these cells were frankly necrotic. Haemocytometer counts were paralleled by both lactate dehydrogenase release and the methyl-thiazol-tetrazolium assays. Arecoline is cytotoxic via necrosis for endothelium, while biochemical assays indicate no appreciable cellular leakage before death and detachment, as well as no clear effect on mitochondrial function in viable cells. Arecoline toxicity may thus contribute to reduced vascularity in oral submucous fibrosis. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Novel cytotoxic annonaceous acetogenins from Annona muricata.

    Science.gov (United States)

    Chang, F R; Wu, Y C

    2001-07-01

    Seven new annonaceous acetogenins, muricins A-G (1-7), as well as five known compounds, a mixture of muricatetrocin A (8) and muricatetrocin B (9), longifolicin (10), corossolin (11), and corossolone (12), were isolated from the seeds of Annona muricata. The structures of all isolates were elucidated and characterized by spectral and chemical methods. These acetogenins showed significantly selective in vitro cytotoxicities toward the human hepatoma cell lines Hep G(2) and 2,2,15.

  14. A New Cytotoxic Alkenylresorcinol from Embelia schimperi

    Directory of Open Access Journals (Sweden)

    Blanche L. Ndontsa

    2014-01-01

    Full Text Available An investigation of MeOH extract of Embelia schimperi stem led to the isolation of a new resorcinol derivative, 5-(7’Z-pentadecenylresorcinol (1, along with the known compounds lupeol (2 and β-sitosterol glucoside (3. The structures of isolated compounds were elucidated using spectroscopic methods. Compound 1 exhibited moderate in vitro cytotoxic activity against human Hela cell line.

  15. Cytotoxic limonoids from Trichilia americana leaves.

    Science.gov (United States)

    Ji, Kai-Long; Zhang, Ping; Li, Xiao-Nian; Guo, Juan; Hu, Hua-Bin; Xiao, Chun-Fen; Xie, Xiang-Qun; Xu, You-Kai

    2015-10-01

    Ten cedrelone limonoids were isolated from the leaves of Trichilia americana. These compounds include americanolides A-D (1-4), 1,2-dihydrodeacetylhirtin (5), 1α-hydroxy-1,2-dihydrodeacetylhirtin (6), 1α-hydroxy-1,2-dihydrohirtin (7), 1α-methoxy-1,2-dihydrodeacetylhirtin (8), 11β-hydroxy-12α-propanoyloxycedrelone (9), and 1α,11β-dihydroxy-1,2-dihydrocedrelone (10), as well as two previously reported compounds, deacetylhirtin (11) and hirtin (12). Their structures were characterized on the basis of spectroscopic studies, and the assignment of the absolute configuration of americanolide A (1) was supported by single-crystal X-ray diffraction studies. The cytotoxic activities of all isolated compounds were also evaluated against five human tumour cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW-480) using an MTS assay. Compounds 11 and 12 showed significant cytotoxicity with IC50 values ranging from 0.1 to 0.5 μM, and compounds 5, 6, 7, 8, 9, and 10 exhibited potent or selective cytotoxic activity with IC50 values ranging from 1.0 to 39.6 μM. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Co-incubation with IL-18 potentiates antigen-specific IFN-γ response in a whole-blood stimulation assay for measurement of cell-mediated immune responses in pigs experimentally infected with Lawsonia intracellularis

    DEFF Research Database (Denmark)

    Riber, Ulla; Boesen, Henriette Toft; Jakobsen, Jeanne Toft

    2011-01-01

    The whole-blood interferon-gamma (IFN-γ) assay is a quantitative in-vitro assay for a direct read out of Ag-specific cell-mediated immune (CMI) responses to infectious diseases. The IFN-γ assay is robust in severe intracellular infections like Brucella or mycobacteria, but more difficult to evalu......The whole-blood interferon-gamma (IFN-γ) assay is a quantitative in-vitro assay for a direct read out of Ag-specific cell-mediated immune (CMI) responses to infectious diseases. The IFN-γ assay is robust in severe intracellular infections like Brucella or mycobacteria, but more difficult...

  17. Absence of cytotoxic antibody to human immunodeficiency virus-infected cells in humans and its induction in animals after infection or immunization with purified envelope glycoprotein gp120

    International Nuclear Information System (INIS)

    Nara, P.L.; Robey, W.G.; Gonda, M.A.; Carter, S.G.; Fischinger, P.J.

    1987-01-01

    The presence of antibody-dependent complement-mediated cytotoxicity (ACC) was assessed in humans and chimpanzees, which are capable of infection with human immunodeficiency virus isolate HTLV-IIIb, and examined in the goat after immunization with the major viral glycoprotein (gp120) of HTLV-IIIb. In infected humans no antibody mediating ACC was observed regardless of the status of disease. Even healthy individuals with high-titer, broadly reactive, neutralizing antibodies has no ACC. In contrast, chimpanzees infected with HTLV-IIIb, from whom virus could be isolated, not only had neutralizing antibody but also antibodies broadly reactive in ACC, even against distantly related human immunodeficiency virus isolates, as well as against their own reisolated virus. In the goat, the gp120 of HTLV-IIIb induced a highly type-specific response as measured by both ACC and flow cytofluorometry of live infected H9 cells. Normal human cells were not subject to ACC by animal anti-HTLV-III gp120-specific sera. Induction of ACC and neutralizing antibody were closely correlated in the animal experimental models but not in humans. The presence of ACC in gp120-inoculated goats and HTLV-III-infected chimpanzees represent a qualitative difference that may be important in the quest for the elicitation of a protective immunity in humans

  18. Absence of cytotoxic antibody to human immunodeficiency virus-infected cells in humans and its induction in animals after infection or immunization with purified envelope glycoprotein gp120

    Energy Technology Data Exchange (ETDEWEB)

    Nara, P.L.; Robey, W.G.; Gonda, M.A.; Carter, S.G.; Fischinger, P.J.

    1987-06-01

    The presence of antibody-dependent complement-mediated cytotoxicity (ACC) was assessed in humans and chimpanzees, which are capable of infection with human immunodeficiency virus isolate HTLV-IIIb, and examined in the goat after immunization with the major viral glycoprotein (gp120) of HTLV-IIIb. In infected humans no antibody mediating ACC was observed regardless of the status of disease. Even healthy individuals with high-titer, broadly reactive, neutralizing antibodies has no ACC. In contrast, chimpanzees infected with HTLV-IIIb, from whom virus could be isolated, not only had neutralizing antibody but also antibodies broadly reactive in ACC, even against distantly related human immunodeficiency virus isolates, as well as against their own reisolated virus. In the goat, the gp120 of HTLV-IIIb induced a highly type-specific response as measured by both ACC and flow cytofluorometry of live infected H9 cells. Normal human cells were not subject to ACC by animal anti-HTLV-III gp120-specific sera. Induction of ACC and neutralizing antibody were closely correlated in the animal experimental models but not in humans. The presence of ACC in gp120-inoculated goats and HTLV-III-infected chimpanzees represent a qualitative difference that may be important in the quest for the elicitation of a protective immunity in humans.

  19. Opposing effects of CXCR3 and CCR5 deficiency on CD8+ T cell-mediated inflammation in the central nervous system of virus-infected mice

    DEFF Research Database (Denmark)

    de Lemos, Carina; Christensen, Jeanette Erbo; Nansen, Anneline

    2005-01-01

    T cells play a key role in the control of viral infection in the CNS but may also contribute to immune-mediated cell damage. To study the redundancy of the chemokine receptors CXCR3 and CCR5 in regulating virus-induced CD8+ T cell-mediated inflammation in the brain, CXCR3/CCR5 double-deficient mice......-deficient mice were more susceptible to intracerebral infection than CXCR3-deficient mice. Analysis of effector T cell generation revealed an accelerated antiviral CD8+ T cell response in CXCR3/CCR5 double-deficient mice. Furthermore, while the accumulation of CD8+ T cells in the neural parenchyma...... were generated and infected intracerebrally with noncytolytic lymphocytic choriomeningitis virus. Because these chemokine receptors are mostly expressed by overlapping subsets of activated CD8+ T cells, it was expected that absence of both receptors would synergistically impair effector T cell invasion...

  20. The interleukin-15 system suppresses T cell-mediated autoimmunity by regulating negative selection and nT(H)17 cell homeostasis in the thymus.

    Science.gov (United States)

    Hou, Mau-Sheng; Huang, Shih-Ting; Tsai, Ming-Han; Yen, Ching-Cheng; Lai, Yein-Gei; Liou, Yae-Huei; Lin, Chih-Kung; Liao, Nan-Shih

    2015-01-01

    The interleukin-15 (IL-15) system is important for regulating both innate and adaptive immune responses, however, its role in autoimmune disease remained unclear. Here we found that Il15(-/-) and Il15ra(-/-) mice spontaneously developed late-onset autoimmune phenotypes. CD4(+) T cells of the knockout mice showed elevated autoreactivity as demonstrated by the induction of lymphocyte infiltration in the lacrimal and salivary glands when transferred into nude mice. The antigen-presenting cells in the thymic medullary regions expressed IL-15 and IL-15Rα, whose deficiency resulted in insufficient negative selection and elevated number of natural IL-17A-producing CD4(+) thymocytes. These findings reveal previously unknown functions of the IL-15 system in thymocyte development, and thus a new layer of regulation in T cell-mediated autoimmunity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Daratumumab-mediated lysis of primary multiple myeloma cells is enhanced in combination with the human anti-KIR antibody IPH2102 and lenalidomide

    DEFF Research Database (Denmark)

    Nijhof, I. S.; Lammerts van Bueren, J. J.; van Kessel, B.

    2015-01-01

    killer cell inhibitory receptors with the human monoclonal anti-KIR antibody IPH2102, next to activation of natural killer cells with the immune modulatory drug lenalidomide. In 4-hour antibody-dependent cell-mediated cytotoxicity assays, IPH2102 did not induce lysis of multiple myeloma cell lines......RIIa-131R allele, who bind IgG1 with lower affinity than patients carrying the FcgammaRIIIa-158V allele or the FcgammaRIIa-131H allele. Finally, a further synergistically improved myeloma cell lysis with the daratumumab-IPH2102 combination was observed by adding lenalidomide, which suggests that more...

  2. Detection of herpes simplex virus type 2 (HSV-2) -specific cell-mediated immune responses in guinea pigs during latent HSV-2 genital infection.

    Science.gov (United States)

    Perry, Clarice L; Banasik, Brianne N; Gorder, Summer R; Xia, Jingya; Auclair, Sarah; Bourne, Nigel; Milligan, Gregg N

    2016-12-01

    Genital infections with herpes simplex virus type 2 (HSV-2) are a source of considerable morbidity and are a health concern for newborns exposed to virus during vaginal delivery. Additionally, HSV-2 infection diminishes the integrity of the vaginal epithelium resulting in increased susceptibility of individuals to infection with other sexually transmitted pathogens. Understanding immune protection against HSV-2 primary infection and immune modulation of virus shedding events following reactivation of the virus from latency is important for the development of effective prophylactic and therapeutic vaccines. Although the murine model of HSV-2 infection is useful for understanding immunity following immunization, it is limited by the lack of spontaneous reactivation of HSV-2 from latency. Genital infection of guinea pigs with HSV-2 accurately models the disease of humans including the spontaneous reactivation of HSV-2 from latency and provides a unique opportunity to examine virus-host interactions during latency. Although the guinea pig represents an accurate model of many human infections, relatively few reagents are available to study the immunological response to infection. To analyze the cell-mediated immune response of guinea pigs at extended periods of time after establishment of HSV-2 latency, we have modified flow-cytometry based proliferation assays and IFN-γ ELISPOT assays to detect and quantify HSV-specific cell-mediated responses during latent infection of guinea pigs. Here we demonstrate that a combination of proliferation and ELISPOT assays can be used to quantify and characterize effecter function of virus-specific immune memory responses during HSV-latency. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Depression of Complement Regulatory Factors in Rat and Human Renal Grafts Is Associated with the Progress of Acute T-Cell Mediated Rejection.

    Directory of Open Access Journals (Sweden)

    Kazuaki Yamanaka

    Full Text Available The association of complement with the progression of acute T cell mediated rejection (ATCMR is not well understood. We investigated the production of complement components and the expression of complement regulatory proteins (Cregs in acute T-cell mediated rejection using rat and human renal allografts.We prepared rat allograft and syngeneic graft models of renal transplantation. The expression of Complement components and Cregs was assessed in the rat grafts using quantitative real-time PCR (qRT-PCR and immunofluorescent staining. We also administered anti-Crry and anti-CD59 antibodies to the rat allograft model. Further, we assessed the relationship between the expression of membrane cofactor protein (MCP by immunohistochemical staining in human renal grafts and their clinical course.qRT-PCR results showed that the expression of Cregs, CD59 and rodent-specific complement regulator complement receptor 1-related gene/protein-y (Crry, was diminished in the rat allograft model especially on day 5 after transplantation in comparison with the syngeneic model. In contrast, the expression of complement components and receptors: C3, C3a receptor, C5a receptor, Factor B, C9, C1q, was increased, but not the expression of C4 and C5, indicating a possible activation of the alternative pathway. When anti-Crry and anti-CD59 mAbs were administered to the allograft, the survival period for each group was shortened. In the human ATCMR cases, the group with higher MCP expression in the grafts showed improved serum creatinine levels after the ATCMR treatment as well as a better 5-year graft survival rate.We conclude that the expression of Cregs in allografts is connected with ATCMR. Our results suggest that controlling complement activation in renal grafts can be a new strategy for the treatment of ATCMR.

  4. Inhibitors of histone deacetylase 1 reverse the immune evasion phenotype to enhance T-cell mediated lysis of prostate and breast carcinoma cells.

    Science.gov (United States)

    Gameiro, Sofia R; Malamas, Anthony S; Tsang, Kwong Y; Ferrone, Soldano; Hodge, James W

    2016-02-16

    The clinical promise of cancer immunotherapy relies on the premise that the immune system can recognize and eliminate tumor cells identified as non-self. However, tumors can evade host immune surveillance through multiple mechanisms, including epigenetic silencing of genes involved in antigen processing and immune recognition. Hence, there is an unmet clinical need to develop effective therapeutic strategies that can restore tumor immune recognition when combined with immunotherapy, such as immune checkpoint blockade and therapeutic cancer vaccines. We sought to examine the potential of clinically relevant exposure of prostate and breast human carcinoma cells to histone deacetylase (HDAC) inhibitors to reverse tumor immune escape to T-cell mediated lysis. Here we demonstrate that prostate (LNCAP) and breast (MDA-MB-231) carcinoma cells are more sensitive to T-cell mediated lysis in vitro after clinically relevant exposure to epigenetic therapy with either the pan-HDAC inhibitor vorinostat or the class I HDAC inhibitor entinostat. This pattern of immunogenic modulation was observed against a broad range of tumor-associated antigens, such as CEA, MUC1, PSA, and brachyury, and associated with augmented expression of multiple proteins involved in antigen processing and tumor immune recognition. Genetic and pharmacological inhibition studies identified HDAC1 as a key determinant in the reversal of carcinoma immune escape. Further, our findings suggest that the observed reversal of tumor immune evasion is driven by a response to cellular stress through activation of the unfolded protein response. This offers the rationale for combining HDAC inhibitors with immunotherapy, including therapeutic cancer vaccines.

  5. Mechanical properties and cytotoxicity of a resorbable bioactive implant prepared by rapid prototyping technique.

    Science.gov (United States)

    El-Ghannam, Ahmed; Hart, Amanda; White, Dean; Cunningham, Larry

    2013-10-01

    Bioceramic processing using rapid prototyping technique (RPT) results in a fragile device that requires thermal treatment to improve the mechanical properties. This investigation evaluates the effect of thermal treatment on the mechanical, porosity, and bioactivity properties as well as the cytotoxicity of a porous silica-calcium phosphate nanocomposite (SCPC) implant prepared by RPT. Porous SCPC implant was subject to 3-h treatment at 800°C, 850°C, or 900°C. The compressive strength (s) and modulus of elasticity (E) were doubled when the sintering temperature is raised from 850 to 900°C measuring (s = 15.326 ± 2.95 MPa and E = 1095 ± 164 MPa) after the later treatment. The significant increase in mechanical properties takes place with minimal changes in the surface area and the percentage of pores in the range 1-356 μm. The SCPC implant prepared at 900°C was loaded with rh-BMP-2 and grafted into a segmental defect in the rabbit ulna. Histology analyses showed highly vascularized bone formation inside the defect. Histopathological analyses of the liver, spleen, kidney, heart, and the lung of rabbits grafted with and without SCPC demonstrated healthy tissues with no signs of toxicity or morphology alterations. Results of the study suggest that it is possible to engineering the mechanical properties of the SCPC implant without compromising its bioactivity. The enhanced bone formation inside the porous SCPC facilitated cell-mediated graft resorption and prohibited any accumulation of the material in the body organs. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

  6. Innate-like Cytotoxic Function of Bystander-Activated CD8+T Cells Is Associated with Liver Injury in Acute Hepatitis A.

    Science.gov (United States)

    Kim, Jihye; Chang, Dong-Yeop; Lee, Hyun Woong; Lee, Hoyoung; Kim, Jong Hoon; Sung, Pil Soo; Kim, Kyung Hwan; Hong, Seon-Hui; Kang, Wonseok; Lee, Jino; Shin, So Youn; Yu, Hee Tae; You, Sooseong; Choi, Yoon Seok; Oh, Insoo; Lee, Dong Ho; Lee, Dong Hyeon; Jung, Min Kyung; Suh, Kyung-Suk; Hwang, Shin; Kim, Won; Park, Su-Hyung; Kim, Hyung Joon; Shin, Eui-Cheol

    2018-01-16

    Acute hepatitis A (AHA) involves severe CD8 + T cell-mediated liver injury. Here we showed during AHA, CD8 + T cells specific to unrelated viruses became activated. Hepatitis A virus (HAV)-infected cells produced IL-15 that induced T cell receptor (TCR)-independent activation of memory CD8 + T cells. TCR-independent activation of non-HAV-specific CD8 + T cells were detected in patients, as indicated by NKG2D upregulation, a marker of TCR-independent T cell activation by IL-15. CD8 + T cells derived from AHA patients exerted innate-like cytotoxicity triggered by activating receptors NKG2D and NKp30 without TCR engagement. We demonstrated that the severity of liver injury in AHA patients correlated with the activation of HAV-unrelated virus-specific CD8 + T cells and the innate-like cytolytic activity of CD8 + T cells, but not the activation of HAV-specific T cells. Thus, host injury in AHA is associated with innate-like cytotoxicity of bystander-activated CD8 + T cells, a result with implications for acute viral diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Monocytes and the 38kDa-antigen of mycobacterium tuberculosis modulate natural killer cell activity and their cytolysis directed against ovarian cancer cell lines

    Directory of Open Access Journals (Sweden)

    Gottschalk Nina

    2012-10-01

    Full Text Available Abstract Background Despite strong efforts to improve clinical outcome of ovarian cancer patients by conventional and targeted immuno-based therapies, the prognosis of advanced ovarian cancer is still poor. Natural killer (NK cells mediate antibody-dependent cellular cytotoxicity (ADCC, release immunostimulatory cytokines and thus function as potent anti-tumour effector cells. However, tumour cells developed mechanisms to escape from an effective immune response. So highly immunogenic substances, like the 38 kDa-preparation of M. tuberculosis, PstS-1, are explored for their potential to enhance cancer-targeted immune responses. In this study we examined the modulation of different NK cell functions by accessory monocytes and PstS-1. We focussed on NK cell activation as well as natural and antibody-dependent cellular cytotoxicity directed against epidermal-growth-factor-receptor (EGFR-positive ovarian cancer cell lines. Methods Activation, cytokine release and cytotoxicity of NK cells stimulated by monocytes and PstS-1 were determined by FACS-analysis, ELISA, Bioplex assay and quantitative polymerase-chain reaction (qPCR. Transwell assays were used to discriminate cell-cell contact-dependent from contact-independent mechanisms. Five ovarian cancer cell lines (A2780, IGROV-1, OVCAR-3, OVCAR-4 and SKOV-3 with different EGFR-expression were used as target cells for natural and antibody-dependent cellular cytotoxicity assays. Cetuximab (anti-EGFR-antibody was used for ADCC studies. Results Our data show that monocytes effectively enhance activation as well natural and antibody-dependent cytolytic activity of NK cells. PstS-1 directly stimulated monocytes and further activated monocyte-NK-co-cultures. However, PstS-1 did not directly influence purified NK cells and did also not affect natural and antibody-dependent cellular cytotoxicity directed against EGFR-positive ovarian cancer cells, even in presence of monocytes. Direct cell-cell contact between

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

    NARCIS (Netherlands)

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

    2016-01-01

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

  9. Characterization of Antibody-Dependent Killing of Trypanosomes by Macrophages.

    Science.gov (United States)

    1985-01-01

    specific antibody, murine peritoneal macrophages and macrophage-like cell lines bind Trypanosoma rhodesiense parasites in vitro. Using a large bank of anti ...as T. cruzi are able to actively penetrate host cells. However, the mechanism of cellular uptake of T. rhodesiense is not known. We therefore...intracellular parasites. Am. J. Trop. Med. Hyg. 26:161. 18. Takayanagi, T. and Y. Nakatake. 1977. Trypanosoma fambiense: The binding activity of antiserum to

  10. Characterization of Antibody-Dependent Killing of Trypanosomes by Macrophages.

    Science.gov (United States)

    1983-04-01

    werse e f08~m~ id’ Vm@ Trpnsm rhodesiense; trypanosomes; African trypanosomiasis ; protozoa, jpiiii tes macrophages; phagocytosis; antibody SEE...agglutinating antibody in the 19H im oglobulin fraction of rabbit antistrum during eaxwtntal African trypanosomiasis . .:283-292. Silverstein, S.C., R.N...species specificity in the action of complement since dog, human , guinea pig and mouse sera could be used as complement sources.4 In the presence of

  11. The combination of IL-21 and IFN-alpha boosts STAT3 activation, cytotoxicity and experimental tumor therapy

    DEFF Research Database (Denmark)

    Eriksen, Karsten W; Søndergaard, Henrik; Woetmann, Anders

    2008-01-01

    such as IFN-alpha and IL-2 have multiple and severe side effects. Accordingly, they are generally used at sub-optimal doses, which limit their clinical efficacy. Here we hypothesized that a combination of IFN-alpha and IL-21, a novel cytokine of the IL-2 family with anti-cancer effects, will increase the anti......-cancer efficacy at sub-optimal cytokine doses. We show that the combined stimulation of target-cells with IFN-alpha and IL-21 triggers an increased STAT3 activation whereas the activation of other STATs including STAT1/2 is unaffected. In parallel, the combined stimulation with IFN-alpha and IL-21 triggers...... a selective increase in MHC class I expression and NK- and CD8(+) T-cell-mediated cytotoxicity. In an experimental in vivo model of renal carcinoma, the combined treatment of IFN-alpha and IL-21 also produces a significant anti-cancer effect as judged by an inhibition of tumor growth and an increased survival...

  12. Vitamin B12 and Folic Acid Imbalance Modifies NK Cytotoxicity, Lymphocytes B and Lymphoprolipheration in Aged Rats

    Directory of Open Access Journals (Sweden)

    Teresa Partearroyo

    2013-11-01

    Full Text Available Different vitamin B12 and folic acid concentrations could exacerbate the immune response. The aim was to evaluate different dietary folic acid and vitamin B12 levels on the immune response in aged rats. Male Sprague Dawley aged rats were assigned to three folic acid groups (deficient, control, supplemented each in absence of vitamin B12 for 30 days. Several parameters of innate and acquired immune responses were measured. Serum and hepatic folate levels increased according to folic acid dietary level, while vitamin B12 levels decreased. There was a significant decrease in natural killer cell-mediated cytotoxicity in the spleen for the vitamin B12 deficient diet and folic acid control diet groups. Significant changes in CD45 lymphocyte subsets were also observed according to dietary imbalance. Lymphoproliferative response to concanavalin A and phytohemagglutinin did not differ significantly between groups. The spleen response to lipopolysaccharide increased significantly, but was unmodified for the other organs. An imbalance between dietary vitamin B12 and folic acid concentrations alters some immunological parameters in aged rats. Therefore, the ratio between folate and vitamin B12 could be as important as their absolute dietary concentrations.

  13. 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.

  14. 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

  15. In vitro cytotoxicity of metallic ions released from dental alloys.

    Science.gov (United States)

    Milheiro, Ana; Nozaki, Kosuke; Kleverlaan, Cornelis J; Muris, Joris; Miura, Hiroyuki; Feilzer, Albert J

    2016-05-01

    The cytotoxicity of a dental alloy depends on, but is not limited to, the extent of its corrosion behavior. Individual ions may have effects on cell viability that are different from metals interacting within the alloy structure. We aimed to investigate the cytotoxicity of individual metal ions in concentrations similar to those reported to be released from Pd-based dental alloys on mouse fibroblast cells. Metal salts were used to prepare seven solutions (concentration range 100 ppm-1 ppb) of the transition metals, such as Ni(II), Pd(II), Cu(II), and Ag(I), and the metals, such as Ga(III), In(III), and Sn(II). Cytotoxicity on mouse fibroblasts L929 was evaluated using the MTT assay. Ni, Cu, and Ag are cytotoxic at 10 ppm, Pd and Ga at 100 ppm. Sn and In were not able to induce cytotoxicity at the tested concentrations. Transition metals were able to induce cytotoxic effects in concentrations similar to those reported to be released from Pd-based dental alloys. Ni, Cu, and Ag were the most cytotoxic followed by Pd and Ga; Sn and In were not cytotoxic. Cytotoxic reactions might be considered in the etiopathogenesis of clinically observed local adverse reactions.

  16. 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.

  17. 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.

  18. 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.

  19. Cytotoxic halogenated monoterpenes from Plocamium cartilagineum.

    Science.gov (United States)

    Sabry, Omar M M; Goeger, Douglas E; Valeriote, Frederick A; Gerwick, William H

    2017-02-01

    As a result of our efforts to identify bioactive agents from marine algae, we have isolated and identified one new halogenated monoterpene 1 [(-)-(5E,7Z)-348-trichloro-7-dichloromethyl-3-methyl-157-octatriene] in addition to three known compounds (2, 3 and 4) from the red alga Plocamium cartilagineum collected by hand from the eastern coast of South Africa. Compound 1 was found to be active as a cytotoxic agent in human lung cancer (NCI-H460) and mouse neuro-2a cell lines (IC 50 4 μg/mL). Two of these compounds (3 and 4) were found to have cytotoxic activity in other cell line assays, especially against human leukaemia and human colon cancers (IC 50 1.3 μg/mL). None of these metabolites were active as sodium channel blockers or activators. All structures were determined by spectroscopic methods (UV, IR, LRMS, HRMS, 1D NMR and 2D NMR). 1D and 2D NOE experiments were carried out on these compounds to confirm the geometry of the double bonds.

  20. Triterpenes from Euphorbia hirta and their cytotoxicity.

    Science.gov (United States)

    Ragasa, Consolacion Y; Cornelio, Kimberly B

    2013-09-01

    To investigate the chemical constituents of the stems, leaves and roots of Euphorbia hirta, and to test for the cytotoxic and antimicrobial potentials of the major constituents of the plant. The compounds were isolated by silica gel chromatography and their structures were elucidated by NMR spectroscopy. The cytotoxicity tests were conducted using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, while the antimicrobial tests employed the agar well method. The air-dried stems of E. hirta afforded taraxerone 1, a mixture of 25-hydroperoxycycloart-23-en-3β-ol (2a) and 24-hydroperoxycycloart-25-en-3β-ol (2b) (sample 2) in a 2 : 1 ratio, and another mixture of cycloartenol (3a), lupeol (3b), α-amyrin (3c) and β-amyrin (3d) (sample 3) in a 0.5 : 4 : 1 : 1 ratio. The air-dried leaves of E. hirta yielded sample 2 in a 3 : 2 ratio, sample 3 in a 2 : 3 : 1 : 1 ratio, phytol and phytyl fatty acid ester, while the roots afforded sample 2 in a 2 : 1 ratio, sample 3 in a 2 : 1 : 1 : 1 ratio, a mixture of cycloartenyl fatty acid ester 4a, lupeol fatty acid ester 4b, α-amyrin fatty acid ester 4c and β-amyrin fatty acid ester 4d (sample 4) in a 3 : 2 : 1 : 1 ratio, linoleic acid, β-sitosterol and squalene. Compound 1 from the stems, sample 2 from the leaves, and sample 3 from the stems were assessed for cytotoxicity against a human cancer cell line, colon carcinoma (HCT 116). Sample 2 showed good activity with an IC50 value of 4.8 μg·mL(-1), while 1 and sample 3 were inactive against HCT 116. Sample 2 was further tested for cytotoxicity against non-small cell lung adenocarcinoma (A549). It showed good activity against this cell line with an IC50 value of 4.5 μg·mL(-1). Antimicrobial assays were conducted on 1 and sample 2. Results of the study indicated that 1 was active against the bacteria: Pseudomonas aeruginosa and Staphylococcus aureus, but was inactive against Escherichia coli and Bacillus subtilis. Sample 2 was active against the

  1. DNA prime/Adenovirus boost malaria vaccine encoding P. falciparum CSP and AMA1 induces sterile protection associated with cell-mediated immunity.

    Directory of Open Access Journals (Sweden)

    Ilin Chuang

    Full Text Available BACKGROUND: Gene-based vaccination using prime/boost regimens protects animals and humans against malaria, inducing cell-mediated responses that in animal models target liver stage malaria parasites. We tested a DNA prime/adenovirus boost malaria vaccine in a Phase 1 clinical trial with controlled human malaria infection. METHODOLOGY/PRINCIPAL FINDINGS: The vaccine regimen was three monthly doses of two DNA plasmids (DNA followed four months later by a single boost with two non-replicating human serotype 5 adenovirus vectors (Ad. The constructs encoded genes expressing P. falciparum circumsporozoite protein (CSP and apical membrane antigen-1 (AMA1. The regimen was safe and well-tolerated, with mostly mild adverse events that occurred at the site of injection. Only one AE (diarrhea, possibly related to immunization, was severe (Grade 3, preventing daily activities. Four weeks after the Ad boost, 15 study subjects were challenged with P. falciparum sporozoites by mosquito bite, and four (27% were sterilely protected. Antibody responses by ELISA rose after Ad boost but were low (CSP geometric mean titer 210, range 44-817; AMA1 geometric mean micrograms/milliliter 11.9, range 1.5-102 and were not associated with protection. Ex vivo IFN-γ ELISpot responses after Ad boost were modest (CSP geometric mean spot forming cells/million peripheral blood mononuclear cells 86, range 13-408; AMA1 348, range 88-1270 and were highest in three protected subjects. ELISpot responses to AMA1 were significantly associated with protection (p = 0.019. Flow cytometry identified predominant IFN-γ mono-secreting CD8+ T cell responses in three protected subjects. No subjects with high pre-existing anti-Ad5 neutralizing antibodies were protected but the association was not statistically significant. SIGNIFICANCE: The DNA/Ad regimen provided the highest sterile immunity achieved against malaria following immunization with a gene-based subunit vaccine (27%. Protection

  2. Cytotoxicity of lapachol metabolites produced by probiotics.

    Science.gov (United States)

    Oliveira Silva, E; Cruz de Carvalho, T; Parshikov, I A; Alves dos Santos, R; Silva Emery, F; Jacometti Cardoso Furtado, N A

    2014-07-01

    Probiotics are currently added to a variety of functional foods to provide health benefits to the host and are commonly used by patients with gastrointestinal complaints or diseases. The therapeutic effects of lapachol continue to inspire studies to obtain derivatives with improved bioactivity and lower unwanted effects. Therefore, the general goal of this study was to show that probiotics are able to convert lapachol and are important to assess the effects of bacterial metabolism on drug performance and toxicity. The microbial transformations of lapachol were carried out by Bifidobacterium sp. and Lactobacillus acidophilus and different metabolites were produced in mixed and isolated cultures. The cytotoxic activities against breast cancer and normal fibroblast cell lines of the isolated metabolites (4α-hydroxy-2,2-dimethyl-5-oxo-2,3,4,4α,5,9β-hexahydroindeno[1,2-β]pyran-9β-carboxilic acid, a new metabolite produced by mixed culture and dehydro-α-lapachone produced by isolated cultures) were assessed and compared with those of lapachol. The new metabolite displayed a lower activity against a breast cancer cell line (IC50 = 532.7 μmol l(-1) ) than lapachol (IC50 = 72.3 μmol l(-1) ), while dehydro-α-lapachone (IC50 = 10.4 μmol l(-1) ) displayed a higher activity than lapachol. The present study is the first to demonstrate that probiotics are capable of converting lapachol into the most effective cytotoxic compound against a breast cancer cell line. Probiotics have been used in dairy products to promote human health and have the ability to metabolize drugs and other xenobiotics. Naphthoquinones, such as lapachol, are considered privileged scaffolds due to their high propensity to interact with biological targets. The present study is the first to demonstrate that probiotics are capable of converting lapachol into the most effective cytotoxic compound against a breast cancer cell line. The developed approach highlights the importance of probiotics to assess

  3. In vitro cytotoxic and antioxidant properties of the aqueous ...

    African Journals Online (AJOL)

    The in vitro cytotoxic and antioxidant properties of the aqueous, chloroform and methanol extracts of the Dicranopteris linearis leaves were investigated in the present study. The cytotoxic effect was determined against the normal (3T3) and cancer cells' lines (MCF-7, HeLa, HT-29, HL-60, K-562 and MDA-MB-231) using the ...

  4. Lymphocyte cytotoxicity of colchicine in Hiroshima atomic bomb survivors

    International Nuclear Information System (INIS)

    Caplan, R.A.; Odoroff, C.L.; Ozaki, Kyoko; Hamilton, H.B.; Finch, S.C.

    1979-07-01

    The cytotoxicity of colchicine for the peripheral blood lymphocytes of 151 Hiroshima atomic bomb survivors and their controls was determined. No radiation effect was found, but modest age-related changes for the initial number of vialble cells and for the cytotoxicity of colchicine were observed. (author)

  5. 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.

  6. Cytotoxic Effect of Ethanol Extract of Convolvulus arvensis L ...

    African Journals Online (AJOL)

    Purpose: To evaluate the cytotoxic effect of ethanol extract of aerial parts of Convolvulus arvensis against lymphoblastic leukemia, Jurkat cells. Methods: The aerial parts of C. arvensis were collected, identified, powdered and soaked in ethanol. The extract was filtered and evaporated, and the residue assessed for cytotoxic ...

  7. Cytotoxic and Antioxidant Activities of Antidesma thwaitesianum Müll ...

    African Journals Online (AJOL)

    Purpose: To investigate the cytotoxic and antioxidant activities of the fruit and fruit waste (residue and marc) extracts of Antidesma thwaitesianum Müll. Arg., known as mamao in Thai, using chemical and cell-based assays. Methods: The cytotoxicity of mamao fruit and fruit waste extracts obtained by expression, maceration ...

  8. 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.

  9. Cytotoxic, anti-inflammatory and antioxidant activities of four different ...

    African Journals Online (AJOL)

    Purpose: To evaluate the cytotoxic, anti-inflammatory and antioxidant activities of four different solvent extracts obtained from the aerial parts of Galega officinalis L. Methods: The hexane, DCM, methanol and water extracts of G. officinalis were successively obtained by soxhlet extraction method. The cytotoxic activity of the ...

  10. 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 ...

  11. 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 ...

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

    African Journals Online (AJOL)

    Cytotoxic activity of Agave lechuguilla Torr. Florita Ramos Casillas, Azucena Oranday Cardenas, Catalina Rivas Morales, Ma. ... The extract and isolated saponins were tested for their cytotoxicity against Vero cells, where they showed IC50 values of 126, 171.6 and 172.2 μg/ml, respectively. Key words: Agave lechuguilla, ...

  13. In vitro cytotoxicity of metallic ions released from dental alloys

    NARCIS (Netherlands)

    Milheiro, A.; Nozaki, K.; Kleverlaan, C.J.; Muris, J.; Miura, H.; Feilzer, A.J.

    2016-01-01

    The cytotoxicity of a dental alloy depends on, but is not limited to, the extent of its corrosion behavior. Individual ions may have effects on cell viability that are different from metals interacting within the alloy structure. We aimed to investigate the cytotoxicity of individual metal ions in

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

    African Journals Online (AJOL)

    The bactericidal activity was heat-resistant and showed minimal cytotoxic effects on human brain microvascular endothelial cells. FPLC revealed eight peaks, with three of them representing compounds that had maximum bactericidal activity against all the tested isolates, but showed < 30 % host cell cytotoxicity. Conclusion: ...

  15. 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 ...

  16. Effect of Boiling on the Cytotoxic and Antioxidant Properties of ...

    African Journals Online (AJOL)

    Boiling had significant effect (p < 0.01) on its antioxidant activity and also on its cytotoxic effect (56 % and 44 % dead cells respectively for Bext and Fext at respectively, at a concentration of 200 μg/ml). Conclusion: It is concluded that B. aegyptiaca aqueous extracts have remarkable cytotoxic activity against stomach cancer ...

  17. Cytotoxic Effect of Turkish Propolis on Liver, Colon, Breast, Cervix ...

    African Journals Online (AJOL)

    Purpose: To investigate the total polyphenolic and flavonoid contents, antioxidant power and cytotoxic activity of ethanol extracts of Turkish propolis (EEP). Methods: The total polyphenolic and flavonoid contents of EEP were determined by spectrometric methods. Antioxidant power and cytotoxic activity of EEP were ...

  18. Synthesis, characterization and cytotoxic activity of palladium (II ...

    Indian Academy of Sciences (India)

    considerable cytotoxicity while the ligands were non-toxic on the tested cell lines. Keywords. Carbohydrate; pyridyl triazole; palladium complexes; cytotoxicity. 1. Introduction. Bioinorganic chemistry is a rapidly developing field dealing with the synthesis and biological investigation of inorganic complexes.1–5 In inorganic ...

  19. Immunization of Mice with a Live Transconjugant Shigella Hybrid Strain Induced Th1 and Th17 Cell-Mediated Immune Responses and Confirmed Passive Protection Against Heterologous Shigellae.

    Science.gov (United States)

    Nag, D; Koley, H; Sinha, R; Mukherjee, P; Sarkar, C; Withey, J H; Gachhui, R

    2016-02-01

    An avirulent, live transconjugant Shigella hybrid (LTSHΔstx) strain was constructed in our earlier study by introducing a plasmid vector, pPR1347, into a Shiga toxin gene deleted Shigella dysenteriae 1. Three successive oral administrations of LTSHΔstx to female adult mice produced comprehensive passive heterologous protection in their offspring against challenge with wild-type shigellae. Production of NO and different cytokines such asIL-12p70, IL-1β and IL-23 in peritoneal mice macrophages indicated that LTSHΔstx induced innate and adaptive immunity in mice. Furthermore, production of IFN-γ, IL-10 and IL-17 in LTSH-primed splenic CD4+ T cell suggested that LTSHΔstx may induce Th1 and Th17 cell-mediated immune responses. Exponential increase of the serum IgG and IgA titre against whole shigellae was observed in immunized adult mice during and after the immunization with the highest peak on day 35. Antigen-specific sIgA was also determined from intestinal lavage of immunized mice. The stomach extracts of neonates from immunized mice, mainly containing mother's milk, contained significant levels of anti-LTSHΔstx immunoglobulin. These studies suggest that the LTSHΔstx could be a new live oral vaccine candidate against shigellosis in the near future. © 2015 The Foundation for the Scandinavian Journal of Immunology.

  20. Recombinant flagellin-PAL fusion protein of Legionella pneumophila induced cell-mediated and protective immunity against bacteremia in BALB/c mice.

    Science.gov (United States)

    Mohabati Mobarez, Ashraf; Ahmadrajabi, Roya; Khoramabadi, Nima; Salmanian, Ali Hatef

    2017-09-08

    We report a new recombinant fusion protein composed of full-length Legionella pneumophila flagellin A and peptidoglycan-associated lipoprotein (PAL), rFLA-PAL, capable of inducing protective immunity against L. pneumophila. The recombinant protein was over expressed in Escherichia coli strain BL21 (DE3) using pET-28a (+) expression vector (pET28a-flaA-pal) and purified by Ni 2+ exchange chromatography. Immunological properties of rFLA-PAL were assessed in a mouse model. Female BALB/c mice, immunized with rFLA-PAL, exhibited a rapid increase in serum antibody concentration against each of its protein portions. Furthermore, a strong activation of both innate and adaptive cell-mediated immunity was observed as indicated by antigen-specific splenocyte proliferation, IFN-γ and IL-12 production, and early production of TNF-α in the serum and in splenocyte cultures which were separately assessed against PAL and FLA. BALB/c mice were challenged with a lethal dose of L. pneumophila intravenously. In a 10-days follow-up after intravenous lethal challenge with L. pneumophila, a 100% survival rate was observed for mice immunized with rFLA-PAL, same as for those immunized with a sublethal dose of L. pneumophila. Based on the potent immune responses observed in mice immunized with rFLA-PAL, this recombinant fusion protein could be a potential vaccine candidate against the intracellular pathogen L. pneumophila.

  1. The CD8⁺ T Cell-Mediated Immunity Induced by HPV-E6 Uploaded in Engineered Exosomes Is Improved by ISCOMATRIXTM Adjuvant.

    Science.gov (United States)

    Manfredi, Francesco; di Bonito, Paola; Ridolfi, Barbara; Anticoli, Simona; Arenaccio, Claudia; Chiozzini, Chiara; Baz Morelli, Adriana; Federico, Maurizio

    2016-11-09

    We recently described the induction of an efficient CD8⁺ T cell-mediated immune response against a tumor-associated antigen (TAA) uploaded in engineered exosomes used as an immunogen delivery tool. This immune response cleared tumor cells inoculated after immunization, and controlled the growth of tumors implanted before immunization. We looked for new protocols aimed at increasing the CD8⁺ T cell specific response to the antigen uploaded in engineered exosomes, assuming that an optimized CD8⁺ T cell immune response would correlate with a more effective depletion of tumor cells in the therapeutic setting. By considering HPV-E6 as a model of TAA, we found that the in vitro co-administration of engineered exosomes and ISCOMATRIX TM adjuvant, i.e., an adjuvant composed of purified ISCOPREP TM saponin, cholesterol, and phospholipids, led to a stronger antigen cross-presentation in both B- lymphoblastoid cell lines ( and monocyte-derived immature dendritic cells compared with that induced by the exosomes alone. Consistently, the co-inoculation in mice of ISCOMATRIX TM adjuvant and engineered exosomes induced a significant increase of TAA-specific CD8⁺ T cells compared to mice immunized with the exosomes alone. This result holds promise for effective usage of exosomes as well as alternative nanovesicles in anti-tumor therapeutic approaches.

  2. The CD8+ T Cell-Mediated Immunity Induced by HPV-E6 Uploaded in Engineered Exosomes Is Improved by ISCOMATRIXTM Adjuvant

    Science.gov (United States)

    Manfredi, Francesco; di Bonito, Paola; Ridolfi, Barbara; Anticoli, Simona; Arenaccio, Claudia; Chiozzini, Chiara; Baz Morelli, Adriana; Federico, Maurizio

    2016-01-01

    We recently described the induction of an efficient CD8+ T cell-mediated immune response against a tumor-associated antigen (TAA) uploaded in engineered exosomes used as an immunogen delivery tool. This immune response cleared tumor cells inoculated after immunization, and controlled the growth of tumors implanted before immunization. We looked for new protocols aimed at increasing the CD8+ T cell specific response to the antigen uploaded in engineered exosomes, assuming that an optimized CD8+ T cell immune response would correlate with a more effective depletion of tumor cells in the therapeutic setting. By considering HPV-E6 as a model of TAA, we found that the in vitro co-administration of engineered exosomes and ISCOMATRIXTM adjuvant, i.e., an adjuvant composed of purified ISCOPREPTM saponin, cholesterol, and phospholipids, led to a stronger antigen cross-presentation in both B- lymphoblastoid cell lines ( and monocyte-derived immature dendritic cells compared with that induced by the exosomes alone. Consistently, the co-inoculation in mice of ISCOMATRIXTM adjuvant and engineered exosomes induced a significant increase of TAA-specific CD8+ T cells compared to mice immunized with the exosomes alone. This result holds promise for effective usage of exosomes as well as alternative nanovesicles in anti-tumor therapeutic approaches. PMID:27834857

  3. CD209a Synergizes with Dectin-2 and Mincle to Drive Severe Th17 Cell-Mediated Schistosome Egg-Induced Immunopathology

    Directory of Open Access Journals (Sweden)

    Parisa Kalantari

    2018-01-01

    Full Text Available The immunopathology caused by schistosome helminths varies greatly in humans and among mouse strains. A severe form of parasite egg-induced hepatic granulomatous inflammation, seen in CBA mice, is driven by Th17 cells stimulated by IL-1β and IL-23 produced by dendritic cells that express CD209a (SIGNR5, a C-type lectin receptor (CLR related to human DC-SIGN. Here, we show that CD209a-deficient CBA mice display decreased Th17 responses and are protected from severe immunopathology. In vitro, CD209a augments the egg-induced IL-1β and IL-23 production initiated by the related CLRs Dectin-2 and Mincle. While Dectin-2 and Mincle trigger an FcRγ-dependent signaling cascade that involves the tyrosine kinase Syk and the trimolecular Card9-Bcl10-Malt1 complex, CD209a promotes the sustained activation of Raf-1. Our findings demonstrate that CD209a drives severe Th17 cell-mediated immunopathology in a helminthic disease based on synergy between DC-SIGN- and Dectin-2-related CLRs.

  4. Impact of T-cell-mediated immune response on xenogeneic heart valve transplantation: short-term success and mid-term failure.

    Science.gov (United States)

    Biermann, Anna C; Marzi, Julia; Brauchle, Eva; Schneider, Maria; Kornberger, Angela; Abdelaziz, Sherif; Wichmann, Julian L; Arendt, Christophe T; Nagel, Eike; Brockbank, Kelvin G M; Seifert, Martina; Schenke-Layland, Katja; Stock, Ulrich A

    2018-04-01

    Allogeneic frozen cryopreserved heart valves (allografts or homografts) are commonly used in clinical practice. A major obstacle for their application is the limited availability in particular for paediatrics. Allogeneic large animal studies revealed that alternative ice-free cryopreservation (IFC) results in better matrix preservation and reduced immunogenicity. The objective of this study was to evaluate xenogeneic (porcine) compared with allogeneic (ovine) IFC heart valves in a large animal study. IFC xenografts and allografts were transplanted in 12 juvenile merino sheep for 1-12 weeks. Immunohistochemistry, ex vivo computed tomography scans and transforming growth factor-β release profiles were analysed to evaluate postimplantation immunopathology. In addition, near-infrared multiphoton imaging and Raman spectroscopy were employed to evaluate matrix integrity of the leaflets. Acellular leaflets were observed in both groups 1 week after implantation. Allogeneic leaflets remained acellular throughout the entire study. In contrast, xenogeneic valves were infiltrated with abundant T-cells and severely thickened over time. No collagen or elastin changes could be detected in either group using multiphoton imaging. Raman spectroscopy with principal component analysis focusing on matrix-specific peaks confirmed no significant differences for explanted allografts. However, xenografts demonstrated clear matrix changes, enabling detection of distinct inflammatory-driven changes but without variations in the level of transforming growth factor-β. Despite short-term success, mid-term failure of xenogeneic IFC grafts due to a T-cell-mediated extracellular matrix-triggered immune response was shown.

  5. B1 Cell IgE Impedes Mast Cell-Mediated Enhancement of Parasite Expulsion through B2 IgE Blockade.

    Science.gov (United States)

    Martin, Rebecca K; Damle, Sheela R; Valentine, Yolander A; Zellner, Matthew P; James, Briana N; Lownik, Joseph C; Luker, Andrea J; Davis, Elijah H; DeMeules, Martha M; Khandjian, Laura M; Finkelman, Fred D; Urban, Joseph F; Conrad, Daniel H

    2018-02-13

    Helminth infection is known for generating large amounts of poly-specific IgE. Here we demonstrate that innate-like B1 cells are responsible for this IgE production during infection with the nematode parasites Nippostrongylus brasiliensis and Heligmosomoides polygyrus bakeri. In vitro analysis of B1 cell immunoglobulin class switch recombination to IgE demonstrated a requirement for anti-CD40 and IL-4 that was further enhanced when IL-5 was added or when the B1 source was helminth infected mice. An IL-25-induced upregulation of IgE in B1 cells was also demonstrated. In T cell-reconstituted RAG1 -/- mice, N. brasiliensis clearance was enhanced with the addition of B2 cells in an IgE-dependent manner. This enhanced clearance was impeded by reconstitution with IgE sufficient B1 cells. Mucosal mast cells mediated the B2 cell enhancement of clearance in the absence of B1 cells. The data support B1 cell IgE secretion as a regulatory response exploited by the helminth. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  6. Cyclophosphamide chemotherapy sensitizes tumor cells to TRAIL-dependent CD8 T cell-mediated immune attack resulting in suppression of tumor growth.

    Directory of Open Access Journals (Sweden)

    Robbert G van der Most

    Full Text Available BACKGROUND: Anti-cancer chemotherapy can be simultaneously lymphodepleting and immunostimulatory. Pre-clinical models clearly demonstrate that chemotherapy can synergize with immunotherapy, raising the question how the immune system can be mobilized to generate anti-tumor immune responses in the context of chemotherapy. METHODS AND FINDINGS: We used a mouse model of malignant mesothelioma, AB1-HA, to investigate T cell-dependent tumor resolution after chemotherapy. Established AB1-HA tumors were cured by a single dose of cyclophosphamide in a CD8 T cell- and NK cell-dependent manner. This treatment was associated with an IFN-alpha/beta response and a profound negative impact on the anti-tumor and total CD8 T cell responses. Despite this negative effect, CD8 T cells were essential for curative responses. The important effector molecules used by the anti-tumor immune response included IFN-gamma and TRAIL. The importance of TRAIL was supported by experiments in nude mice where the lack of functional T cells could be compensated by agonistic anti-TRAIL-receptor (DR5 antibodies. CONCLUSION: The data support a model in which chemotherapy sensitizes tumor cells for T cell-, and possibly NK cell-, mediated apoptosis. A key role of tumor cell sensitization to immune attack is supported by the role of TRAIL in tumor resolution and explains the paradox of successful CD8 T cell-dependent anti-tumor responses in the absence of CD8 T cell expansion.

  7. Primary vaccination with the LiESP/QA-21 vaccine (CaniLeish) produces a cell-mediated immune response which is still present 1 year later.

    Science.gov (United States)

    Moreno, Javier; Vouldoukis, Ioannis; Schreiber, Paul; Martin, Virginie; McGahie, David; Gueguen, Sylvie; Cuisinier, Anne-Marie

    2014-04-15

    Canine leishmaniasis, an important zoonotic disease of dogs, is the result of an ineffective and inappropriate immune response to infection with Leishmania infantum. It is widely accepted that the appropriate immune response is characterised by a T-helper (Th)1-dominated profile in an overall mixed Th1/Th2 response. The absence of a strong Th1 response is associated with progression to the clinical disease. Thus, there is a need for an effective vaccine that could modulate the immune response to a more appropriate profile against the parasite. In this study we measured the impact of the LiESP/QA-21 canine vaccine, recently launched commercially in Europe, on selected humoral and cellular immune markers for one year after a primary vaccination course. The humoral response to vaccination was characterised by a predominantly IgG2 profile. Vaccinated dogs developed long-lasting cell-mediated immune responses against L. infantum, specifically with a stronger ability of macrophages to reduce intracellular parasite burdens in co-culture with autologous lymphocytes compared to control dogs (p=0.0002), which was correlated with induction of inducible nitric oxide synthase (iNOS) and production of nitric oxide (NO) derivatives. These results confirm that vaccination with LiESP/QA-21 is capable of inducing an appropriate Th1-dominated immune profile which persists for a full year. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Earlier low-dose TBI or DST overcomes CD8+ T-cell-mediated alloresistance to allogeneic marrow in recipients of anti-CD40L.

    Science.gov (United States)

    Takeuchi, Yasuo; Ito, Hiroshi; Kurtz, Josef; Wekerle, Thomas; Ho, Leon; Sykes, Megan

    2004-01-01

    Treatment with a single injection of anti-CD40L (CD154) monoclonal antibody (mAb) and fully mismatched allogeneic bone marrow transplant (BMT) allows rapid tolerization of CD4+ T cells to the donor. The addition of in vivo CD8 T-cell depletion leads to permanent mixed hematopoietic chimerism and tolerance. We now describe two approaches that obviate the requirement for CD8 T-cell depletion by rapidly tolerizing recipient CD8 T cells in addition to CD4 cells. Administration of donor-specific transfusion (DST) to mice receiving 3 Gy total body irradiation (TBI), BMT and anti-CD40L mAb on day 0 uniformly led to permanent mixed chimerism and tolerance, compared with only 40% of mice receiving similar treatment without DST. In the absence of DST, moving the timing of 3 Gy TBI to day -1 or day -2 instead of day 0 led to rapid (by 2 weeks) induction of CD8+ cell tolerance, and also permitted uniform achievement of permanent mixed chimerism and donor-specific tolerance in recipients of anti-CD40L and BMT on day 0. These nontoxic regimens overcome CD8+ and CD4+ T-cell-mediated alloresistance without requiring host T-cell depletion, permitting the induction of permanent mixed chimerism and tolerance.

  9. Synthetic long peptide-based vaccine formulations for induction of cell mediated immunity: A comparative study of cationic liposomes and PLGA nanoparticles.

    Science.gov (United States)

    Varypataki, Eleni Maria; Silva, Ana Luisa; Barnier-Quer, Christophe; Collin, Nicolas; Ossendorp, Ferry; Jiskoot, Wim

    2016-03-28

    Nanoparticulate formulations for synthetic long peptide (SLP)-cancer vaccines as alternative to clinically used Montanide ISA 51- and squalene-based emulsions are investigated in this study. SLPs were loaded into TLR ligand-adjuvanted cationic liposomes and PLGA nanoparticles (NPs) to potentially induce cell-mediated immune responses. The liposomal and PLGA NP formulations were successfully loaded with up to four different compounds and were able to enhance antigen uptake by dendritic cells (DCs) and subsequent activation of T cells in vitro. Subcutaneous vaccination of mice with the different formulations showed that the SLP-loaded cationic liposomes were the most efficient for the induction of functional antigen-T cells in vivo, followed by PLGA NPs which were as potent as or even more than the Montanide and squalene emulsions. Moreover, after transfer of antigen-specific target cells in immunized mice, liposomes induced the highest in vivo killing capacity. These findings, considering also the inadequate safety profile of the currently clinically used adjuvant Montanide ISA-51, make these two particulate, biodegradable delivery systems promising candidates as delivery platforms for SLP-based immunotherapy of cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Disruption of Tumor Necrosis Factor Receptor-Associated Factor 5 Exacerbates Murine Experimental Colitis via Regulating T Helper Cell-Mediated Inflammation.

    Science.gov (United States)

    Shang, Jian; Li, Lixia; Wang, Xiaobing; Pan, Huaqin; Liu, Shi; He, Ruohang; Li, Jin; Zhao, Qiu

    2016-01-01

    Tumor necrosis factor (TNF) receptor-associated factor 5 (TRAF5) is a key mediator of TNF receptor superfamily members and is important in both T helper (Th) cell immunity and the regulation of multiple signaling pathways. To clarify TRAF5's influence on inflammatory bowel diseases (IBDs), we investigated TRAF5 deficiency's effect on dextran sulfate sodium- (DSS-) induced colitis. Colitis was induced in TRAF5 knockout (KO) mice and their wild-type (WT) littermates by administering 3% DSS orally for 7 days. The mice were then sacrificed, and their colons were removed. Our data suggested that KO mice were more susceptible to DSS-induced colitis. TRAF5 deficiency significantly enhanced IFN-γ, IL-4, and IL-17a mRNA and protein levels in the colons of DSS-fed mice, and the mRNA expression of T-bet and GATA-3 was also markedly elevated. However, ROR-α and ROR-γt mRNA levels did not differ between DSS-induced KO and WT mice. Flow cytometry showed increased frequencies of Th2 and IFN-γ/IL-17a-coproducing CD4(+) T cells in the colons of DSS-induced KO mice. Additionally, TRAF5 deficiency significantly enhanced the activation of NF-κB in CD4(+) T cells after DSS administration. These results indicated that TRAF5 deficiency significantly aggravated DSS-induced colitis, most likely by regulating Th cell-mediated inflammation.

  11. Cytotoxic and renoprotective diterpenoids from Clerodendranthus spicatus.

    Science.gov (United States)

    Luo, Yong; Li, Xiao-Zhen; Xiang, Bin; Luo, Qi; Liu, Jia-Wang; Yan, Yong-Ming; Sun, Qin; Cheng, Yong-Xian

    2018-03-01

    Three new diterpenoids, spicatusenes A-C (1-3), and eleven known ones (4-14) were isolated from the aerial parts of Clerodendranthus spicatus. Their structures were identified by spectroscopic methods. The cytotoxic activities of all the compounds against human cancer cells (HL-60, SMMC-7721, A-549, MCF-7, and SW-480) were examined and found that compounds 2, 3, 6, 8, 10, and 13 were active against one or more cancer cell lines. Besides, the renoprotective effects of all the isolates in TGF-β1-induced rat kidney fibroblasts revealed that compounds 3-7, 9, 13, and 14 were beneficial for renal fibrosis. Finally, a plausible biosynthetic pathway for 1 via a Hantzsch-type reaction was proposed. Copyright © 2018. Published by Elsevier B.V.

  12. Cytotoxic clerodane diterpenes from Zuelania guidonia.

    Science.gov (United States)

    Calderón, Carlos; De Ford, Christian; Castro, Victor; Merfort, Irmgard; Murillo, Renato

    2014-03-28

    The leaves of Zuelania guidonia yielded eight new clerodane diterpenes, namely, zuelaguidins A-H (1-8), and the known clerodane diterpene esculentin A (9). Some of these structures contained a 3,6-dihydro-1,2-dioxin moiety. The new compounds were isolated and identified using 1D- and 2D-NMR experiments. All compounds were evaluated for cytotoxicity against the CCRF-CEM (human acute lymphocytic leukemia), CEM-ADR5000 (human acute lymphocytic leukemia resistant to doxorubicin), and MIA-PaCa-2 (human pancreatic carcinoma) cell lines as well as for their selectivity against peripheral blood mononuclear cells from healthy human subjects. Zuelaguidins B, C, and E were the most potent compounds against the CCRF-CEM cell line, with IC50 values ranging from 1.6 to 2.5 μM.

  13. Cytotoxicity screening of endemic plants from Guayana highlands.

    Science.gov (United States)

    Guil-Guerrero, José Luis; Campra, Pablo

    2009-08-01

    A chemical-ecology approach has been used to screen plants growing in Guyana Highlands as an indicator of production of biologically active secondary metabolites. Extracts of leaves from 19 species, most of them endemic in this area, and collected at the top of Roraima Tepui (2,723 m) were screened in vitro at different concentrations for their potential cytotoxic activity against three tumour cell lines: HT29 (colon), A549 (lung) and MDA-MB-231 (breast). MTT (tetrazolium blue) colorimetric assay was employed as cytotoxicity test. Extracts of nine species caused less than 30% growth in at least one cell line. From these species, high cytotoxic activity was detected in Casearia sylvestris var. lingua and Ledotamnus sessiliflorus extracts; medium activity was found in Cyathea sp. Two other species, Cyrilla racemiflora and Heliamphora minor showed lower but significant cytotoxicity. Further cytotoxicity-directed fractionation of these extracts would be advisable to isolate and identify the active principles of these plants.

  14. 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.

  15. 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

  16. Monocytic MDSCs regulate macrophage-mediated xenogenic cytotoxicity.

    Science.gov (United States)

    Maeda, Akira; Eguchi, Hiroshi; Nakahata, Kengo; Lo, Pei-Chi; Yamanaka, Kazuaki; Kawamura, Takuji; Matsuura, Rei; Sakai, Rieko; Asada, Mayumi; Okuyama, Hiroomi; Miyagawa, Shuji

    2015-10-01

    Xenotransplantation is considered to be one of the most attractive strategies for overcoming the worldwide shortage of organs. However, many obstructions need to be overcome before it will achieve clinical use in patients. One such obstacle is the development of an effective immunosuppressive strategy. We previously reported that myeloid-derived suppressor cells (MDSCs), a heterogeneous population of progenitor and immature myeloid cells, suppress xenogenic CTL-mediated cytotoxicity. Because of their heterogeneous nature, MDSC can function via several suppressive mechanisms that disrupt both innate and adaptive immunity. Since macrophages play a pivotal role in the rejection of a xenograft, in this study, we evaluated the suppressive effects of MDSC against macrophage-mediated xenogenic rejection. To evaluate the effect of monocyte-derived MDSCs on xenogenic immune reactions, a CFSE(carboxyfluorescein diacetate, succinimidyl ester)assay was employed to assess cytotoxicity. While, in the absence of activation, primed MDSCs had no detectable effect on macrophage-induced cytotoxicity against SEC cells, LPS-activated MDSCs were found to significantly suppress xenogenic cytotoxicity. A CFSE cytotoxicity assay revealed that MDSCs significantly suppressed macrophage-induced cytotoxicity. Furthermore, an indoleamine 2,3 dioxygenase (IDO) inhibitor, 1-methyl tryptophan (1-MT), abolished the MDSC-induced suppression of macrophage-mediated xeno-rejection, indicating that MDSCs may suppress macrophage-mediated cytotoxicity in an IDO-dependent manner. These findings indicate that MDSCs have great potential for immunosuppressing macrophage-mediated xeno-rejection. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Cytotoxicity of alginate for orthodontic use

    Directory of Open Access Journals (Sweden)

    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

  18. Antileishmanial activity and cytotoxicity of Brazilian plants.

    Science.gov (United States)

    Ribeiro, Tatiana G; Chávez-Fumagalli, Miguel A; Valadares, Diogo G; Franca, Juçara R; Lage, Paula S; Duarte, Mariana C; Andrade, Pedro H R; Martins, Vivian T; Costa, Lourena E; Arruda, Ana L A; Faraco, André A G; Coelho, Eduardo A F; Castilho, Rachel O

    2014-08-01

    Leishmaniasis is a major public health problem, and the alarming spread of parasite resistance has increased the importance of discovering new therapeutic products. The present study aimed to investigate the in vitro leishmanicidal activity from 16 different Brazilian medicinal plants. Stationary-phase promastigotes of Leishmania amazonensis and murine macrophages were exposed to 44 plant extracts or fractions for 48 h at 37°C, in order to evaluate their antileishmanial activity and cytotoxicity, respectively. The most potent extracts against L. amazonensis were the hexanic extract of Dipteryx alata (IC50 of 0.08 μg/mL), the hexanic extract of Syzygium cumini (IC50 of 31.64 μg/mL), the ethanolic and hexanic extracts of leaves of Hymenaea courbaril (IC50 of 44.10 μg/mL and 35.84 μg/mL, respectively), the ethanolic extract of H. stignocarpa (IC50 of 4.69 μg/mL), the ethanolic extract of Jacaranda caroba (IC50 of 13.22 μg/mL), and the ethanolic extract of J. cuspidifolia leaves (IC50 of 10.96 μg/mL). Extracts of D. alata and J. cuspidifolia presented higher selectivity index, with high leishmanicidal activity and low cytotoxicity in the mammalian cells. The capacity in treated infected macrophages using the extracts and/or fractions of D. alata and J. cuspidifolia was also analyzed, and reductions of 95.80%, 98.31%, and 97.16%, respectively, in the parasite burden, were observed. No nitric oxide (NO) production could be observed in the treated macrophages, after stimulation with the extracts and/or fractions of D. alata and J. cuspidifolia, suggesting that the biological activity could be due to mechanisms other than macrophage activation mediated by NO production. Based on phytochemistry studies, the classes of compounds that could contribute to the observed activities are also discussed. In conclusion, the data presented in this study indicated that traditional medicinal plant extracts present effective antileishmanial activity. Future studies could focus on

  19. Disruption of Tumor Necrosis Factor Receptor-Associated Factor 5 Exacerbates Murine Experimental Colitis via Regulating T Helper Cell-Mediated Inflammation

    Directory of Open Access Journals (Sweden)

    Jian Shang

    2016-01-01

    Full Text Available Tumor necrosis factor (TNF receptor-associated factor 5 (TRAF5 is a key mediator of TNF receptor superfamily members and is important in both T helper (Th cell immunity and the regulation of multiple signaling pathways. To clarify TRAF5’s influence on inflammatory bowel diseases (IBDs, we investigated TRAF5 deficiency’s effect on dextran sulfate sodium- (DSS- induced colitis. Colitis was induced in TRAF5 knockout (KO mice and their wild-type (WT littermates by administering 3% DSS orally for 7 days. The mice were then sacrificed, and their colons were removed. Our data suggested that KO mice were more susceptible to DSS-induced colitis. TRAF5 deficiency significantly enhanced IFN-γ, IL-4, and IL-17a mRNA and protein levels in the colons of DSS-fed mice, and the mRNA expression of T-bet and GATA-3 was also markedly elevated. However, ROR-α and ROR-γt mRNA levels did not differ between DSS-induced KO and WT mice. Flow cytometry showed increased frequencies of Th2 and IFN-γ/IL-17a-coproducing CD4+ T cells in the colons of DSS-induced KO mice. Additionally, TRAF5 deficiency significantly enhanced the activation of NF-κB in CD4+ T cells after DSS administration. These results indicated that TRAF5 deficiency significantly aggravated DSS-induced colitis, most likely by regulating Th cell-mediated inflammation.

  20. Effects of in ovo exposure to PCBs (coplanar congener, kanechlor mixture, hydroxylated metabolite) on the developing cell-mediated immunity in chickens

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, J.; Matsuda, M.; Kawano, M.; Wakimoto, T. [Faculty of Agriculture, Ehime Univ., Matsuyama, Ehime (Japan); Kashima, Y. [Dept. of Hygiene, Yokohama City Univ. School of Medicine, Yokohama (Japan)

    2004-09-15

    Polychlorinated biphenyls (PCBs) are wide spread environmental contaminants and known to cause various adverse effects on health of human and wildlife. Immune system is one of the several targets for toxic effects of PCBs and its normal balance is often disrupted by the exposure of the compounds. For example, PCBs may induce immune suppression and result in increased susceptibility to bacterial and viral infections, or conversely, excessive immune enhancement may cause adverse outcomes including as autoimmune disease and anergy. Therefore immune function is regarded as one of an important endpoint in toxicological risk assessment. There are a number of studies shown that neonatal organisms perinatally exposed to polyhalogenated aromatic hydrocarbons (PHAHs) such as PCBs have severer effects on their immune system than adult. Dioxins and coplanar PCB congeners, structurally planar PHAHs are known to have high affinity for aryl hydrocarbon receptor (AhR). 2,3,7,8-tetrachlorinated dibenzo-p-dioxin (TCDD) have the strongest affinity among such compounds and these are considered to act on immune system through AhR. On the other hand, such as non-planar PCB congeners with low affinity for AhR, which are abundantly contained in commercial PCB preparations have non-additive (antagonistic) effects on immune function. Prenatal exposure of TCDD to rodent induced abnormal lymphoid development in the thymus and thymus-dependent immune functions were remarkably disturbed. Although several experimental studies in mammals have been carried out on the developmental immunotoxicity of PCBs, there are still limited information available on avian species. Thus in this study, prenatal exposure to low level of PCBs and the effects on the developing immune system were investigated with chicken as a model animal of avian species, especially it is focused on the cell-mediated immune function.

  1. The effect of feed supplementation with zinc chelate and zinc sulphate on selected humoral and cell-mediated immune parameters and cytokine concentration in broiler chickens.

    Science.gov (United States)

    Jarosz, Łukasz; Marek, Agnieszka; Grądzki, Zbigniew; Kwiecień, Małgorzata; Kalinowski, Marcin

    2017-06-01

    The ability of poultry to withstand infectious disease caused by bacteria, viruses or protozoa depends upon the integrity of the immune system. Zinc is important for proper functioning of heterophils, mononuclear phagocytes and T lymphocytes. Numerous data indicate that the demand for zinc in poultry is not met in Poland due to its low content in feeds of vegetable origin. The aim of the study was to determine the effect of supplementation of inorganic (ZnSO 4 and ZnSO 4 + phytase enzyme), and organic forms of zinc (Zn with glycine and Zn with glycine and phytase enzyme) on selected parameters of the cellular and humoral immune response in broiler chickens by evaluating the percentage of CD3 + CD4 + , CD3 + CD8 + , CD25 + , MHC Class II, and BU-1 + lymphocytes, the phagocytic activity of monocytes and heterophils, and the concentration of IL-2, IL-10 and TNF-α in the peripheral blood. Flow cytometry was used to determine selected cell-mediated immune response parameters. Phagocytic activity in whole blood was performed using the commercial Phagotest kit (ORPEGEN-Pharma, Immuniq, Poland). The results showed that supplementation with zinc chelates causes activation of the cellular and humoral immune response in poultry, helping to maintain the balance between the Th1 and Th2 response and enhancing resistance to infections. In contrast with chelates, the use of zinc in the form of sulphates has no immunomodulatory effect and may contribute to the development of local inflammatory processes in the digestive tract, increasing susceptibility to infection. Copyright © 2016. Published by Elsevier Ltd.

  2. Activation of cell-mediated immunity in depression: association with inflammation, melancholia, clinical staging and the fatigue and somatic symptom cluster of depression.

    Science.gov (United States)

    Maes, Michael; Mihaylova, Ivana; Kubera, Marta; Ringel, Karl

    2012-01-10

    Depression is characterized by activation of cell-mediated immunity (CMI), including increased neopterin levels, and increased pro-inflammatory cytokines (PICs), such as interleukin-1 (IL-1) and tumor necrosis factor-α (TNFα). These PICs may induce depressive, melancholic and chronic fatigue (CF) symptoms. We examined serum neopterin and plasma PIC levels in depressive subgroups in relation to the depressive subtypes and the melancholic and CF symptoms of depression. Participants were 85 patients with depression and in 26 normal controls. Severity of depression was assessed with the Hamilton Depression Rating Scale (HDRS) and severity of CF with the Fibromyalgia and Chronic Fatigue Syndrome (FF) Rating Scale. Serum neopterin was significantly higher in depressed patients and in particular in those with melancholia. There were positive correlations between serum neopterin, the plasma PICs and the number of previous depressive episodes. Neopterin and TNFα were associated with melancholia, while both PICs were associated with CF. Melancholia-group membership was predicted by the HDRS and neopterin, and CF group membership by age, the FF score and serum TNFα. Depression and melancholia are accompanied by CMI activation, suggesting that neopterin plays a role in their pathophysiology, e.g. through activation of oxidative and nitrosative stress and apoptosis pathways. The intertwined CMI and inflammatory responses are potentially associated with the onset of depression and with the melancholic and CF symptoms of depression. Exposure to previous depressive episodes may magnify the size of CMI and PIC responses, possibly increasing the likelihood of new depressive episodes. CMI activation and inflammation may contribute to the staging or recurrence of depression. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Increased IgA responses to the LPS of commensal bacteria is associated with inflammation and activation of cell-mediated immunity in chronic fatigue syndrome.

    Science.gov (United States)

    Maes, Michael; Twisk, Frank N M; Kubera, Marta; Ringel, Karl; Leunis, Jean-Claude; Geffard, Michel

    2012-02-01

    Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is accompanied by a) systemic IgA/IgM responses against the lipopolysaccharides (LPS) of commensal bacteria; b) inflammation, e.g. increased plasma interleukin-(IL)1 and tumor necrosis factor (TNF)α; and c) activation of cell-mediated immunity (CMI), as demonstrated by increased neopterin. To study the relationships between the IgA/IgM responses to the LPS of microbiota, inflammation, CMI and the symptoms of ME/CFS we measured the IgA/IgM responses to the LPS of 6 different enterobacteria, serum IL-1, TNFα, neopterin, and elastase in 128 patients with ME/CFS and chronic fatigue (CF). Severity of symptoms was assessed by the Fibromyalgia and Chronic Fatigue Syndrome (FF) Rating Scale. Serum IL-1, TNFα, neopterin and elastase are significantly higher in patients with ME/CFS than in CF patients. There are significant and positive associations between the IgA responses to LPS and serum IL-1, TNFα, neopterin and elastase. Patients with an abnormally high IgA response show increased serum IL-1, TNFα and neopterin levels, and higher ratings on irritable bowel syndrome (IBS) than subjects with a normal IgA response. Serum IL-1, TNFα and neopterin are significantly related to fatigue, a flu-like malaise, autonomic symptoms, neurocognitive disorders, sadness and irritability. The findings show that increased IgA responses to commensal bacteria in ME/CFS are associated with inflammation and CMI activation, which are associated with symptom severity. It is concluded that increased translocation of commensal bacteria may be responsible for the disease activity in some ME/CFS patients. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Primordial germ cell-mediated chimera technology produces viable pure-line Houbara bustard offspring: potential for repopulating an endangered species.

    Directory of Open Access Journals (Sweden)

    Ulrich Wernery

    2010-12-01

    Full Text Available The Houbara bustard (Chlamydotis undulata is a wild seasonal breeding bird populating arid sandy semi-desert habitats in North Africa and the Middle East. Its population has declined drastically during the last two decades and it is classified as vulnerable. Captive breeding programmes have, hitherto, been unsuccessful in reviving population numbers and thus radical technological solutions are essential for the long term survival of this species. The purpose of this study was to investigate the use of primordial germ cell-mediated chimera technology to produce viable Houbara bustard offspring.Embryonic gonadal tissue was dissected from Houbara bustard embryos at eight days post-incubation. Subsequently, Houbara tissue containing gonadal primordial germ cells (gPGCs was injected into White Leghorn chicken (Gallus gallus domesticus embryos, producing 83/138 surviving male chimeric embryos, of which 35 chimeric roosters reached sexual maturity after 5 months. The incorporation and differentiation of Houbara gPGCs in chimeric chicken testis were assessed by PCR with Houbara-specific primers and 31.3% (5/16 gonads collected from the injected chicken embryos showed the presence of donor Houbara cells. A total of 302 semen samples from 34 chimeric roosters were analyzed and eight were confirmed as germline chimeras. Semen samples from these eight roosters were used to artificially inseminate three female Houbara bustards. Subsequently, 45 Houbara eggs were obtained and incubated, two of which were fertile. One egg hatched as a male live born Houbara; the other was female but died before hatching. Genotyping confirmed that the male chick was a pure-line Houbara derived from a chimeric rooster.This study demonstrates for the first time that Houbara gPGCs can migrate, differentiate and eventually give rise to functional sperm in the chimeric chicken testis. This approach may provide a promising tool for propagation and conservation of endangered avian

  5. Transcriptomic Analysis of Persistent Infection with Foot-and-Mouth Disease Virus in Cattle Suggests Impairment of Apoptosis and Cell-Mediated Immunity in the Nasopharynx.

    Directory of Open Access Journals (Sweden)

    Michael Eschbaumer

    Full Text Available In order to investigate the mechanisms of persistent foot-and-mouth disease virus (FMDV infection in cattle, transcriptome alterations associated with the FMDV carrier state were characterized using a bovine whole-transcriptome microarray. Eighteen cattle (8 vaccinated with a recombinant FMDV A vaccine, 10 non-vaccinated were challenged with FMDV A24 Cruzeiro, and the gene expression profiles of nasopharyngeal tissues collected between 21 and 35 days after challenge were compared between 11 persistently infected carriers and 7 non-carriers. Carriers and non-carriers were further compared to 2 naïve animals that had been neither vaccinated nor challenged. At a controlled false-discovery rate of 10% and a minimum difference in expression of 50%, 648 genes were differentially expressed between FMDV carriers and non-carriers, and most (467 had higher expression in carriers. Among these, genes associated with cellular proliferation and the immune response-such as chemokines, cytokines and genes regulating T and B cells-were significantly overrepresented. Differential gene expression was significantly correlated between non-vaccinated and vaccinated animals (biological correlation +0.97, indicating a similar transcriptome profile across these groups. Genes related to prostaglandin E2 production and the induction of regulatory T cells were overexpressed in carriers. In contrast, tissues from non-carrier animals expressed higher levels of complement regulators and pro-apoptotic genes that could promote virus clearance. Based on these findings, we propose a working hypothesis for FMDV persistence in nasopharyngeal tissues of cattle, in which the virus may be maintained by an impairment of apoptosis and the local suppression of cell-mediated antiviral immunity by inducible regulatory T cells.

  6. Anandamide attenuates Th-17 cell-mediated delayed-type hypersensitivity response by triggering IL-10 production and consequent microRNA induction.

    Directory of Open Access Journals (Sweden)

    Austin R Jackson

    Full Text Available Endogenous cannabinoids [endocannabinoids] are lipid signaling molecules that have been shown to modulate immune functions. However, their role in the regulation of Th17 cells has not been studied previously. In the current study, we used methylated Bovine Serum Albumin [mBSA]-induced delayed type hypersensitivity [DTH] response in C57BL/6 mice, mediated by Th17 cells, as a model to test the anti-inflammatory effects of endocannabinoids. Administration of anandamide [AEA], a member of the endocannabinoid family, into mice resulted in significant mitigation of mBSA-induced inflammation, including foot pad swelling, cell infiltration, and cell proliferation in the draining lymph nodes [LN]. AEA treatment significantly reduced IL-17 and IFN-γ production, as well as decreased RORγt expression while causing significant induction of IL-10 in the draining LNs. IL-10 was critical for the AEA-induced mitigation of DTH response inasmuch as neutralization of IL-10 reversed the effects of AEA. We next analyzed miRNA from the LN cells and found that 100 out of 609 miRNA species were differentially regulated in AEA-treated mice when compared to controls. Several of these miRNAs targeted proinflammatory mediators. Interestingly, many of these miRNA were also upregulated upon in vitro treatment of LN cells with IL-10. Together, the current study demonstrates that AEA may suppress Th-17 cell-mediated DTH response by inducing IL-10 which in turn triggers miRNA that target proinflammatory pathways.

  7. The effects of chloroform, ethyl acetate and methanolic extracts of Brassica rapa L. on cell-mediated immune response in mice.

    Science.gov (United States)

    Jafarian-Dehkordi, A; Zolfaghari, B; Mirdamadi, M

    2013-07-01

    Turnips with a long history of usage, are helpful in preventing breast and prostate cancer, inflammation and body`s immune system dysfunction. In this study, we investigated the effects of chloroform, ethyl acetate and methanolic extracts of Brassica rapa L. on cell-mediated immune response in mice. Chloroform, ethyl acetate and methanolic extracts of B. rapa glands were prepared by maceration method. To study the effects of B. rapa on acquired immunity, groups of Balb/c mice (n=8) were used. Sheep red blood cell (SRBC) was injected (s.c., 1×10(8)cells/ml, 0.02 ml) and 5 days later, different extracts (10, 100 and 500 mg/kg), betamethasone (4 mg/kg) and Levamisol (4 mg/kg) as a positive control and normal saline as a negative control were given i.p. After 1 h SRBC was injected to footpad (s.c., 1×10(8)cells/ml, 0.02 ml) and footpad swelling was measured up to 72 h. To investigate the effects of B. rapa on innate immunity the same procedure was used, but animals only received one injection of SRBC 1 h after i.p. injection of test compounds. Our findings showed that SRBC induced an increase in paw swelling with maximum response at 6-8 and 2-4 h for innate and acquired immunity, respectively. Betamethasone inhibited and levamisol increased paw thickness in both models. In both innate and acquired immunity models, chloroform, ethyl acetate and methanolic extracts of B. rapa glands significantly and dose-dependently reduced paw thickness. Ethyl acetate extract showed better effect. As glucosinolates are better extracted by ethyl acetate, it may be concluded that they are contributed in the more pronounced effects of ethyl acetate extract.

  8. 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.

  9. T-cell mediated anti-tumor immunity after photodynamic therapy: Why does it not always work and how can we improve it?

    Science.gov (United States)

    de Freitas, Lucas Freitas; Hamblin, Michael R

    2015-01-01

    Photodynamic therapy (PDT) uses the combination of non-toxic photosensitizers and harmless light to generate reactive oxygen species that destroy tumors by a combination of direct tumor cell killing, vascular shutdown, and activation of the immune system. It has been shown in some animal models that mice that have been cured of cancer by PDT, may exhibit resistance to rechallenge. The cured mice can also possess tumor specific T-cells that recognize defined tumor antigens, destroy tumor cells in vitro, and can be adoptively transferred to protect naïve mice from cancer. However, these beneficial outcomes are the exception rather than the rule. The reasons for this lack of consistency lie in the ability of many tumors to suppress the host immune system and to actively evade immune attack. The presence of an appropriate tumor rejection antigen in the particular tumor cell line is a requisite for T-cell mediated immunity. Regulatory T-cells (CD25+, Foxp3+) are potent inhibitors of anti-tumor immunity, and their removal by low dose cyclophosphamide can potentiate the PDT-induced immune response. Treatments that stimulate dendritic cells (DC) such as CpG oligonucleotide can overcome tumor-induced DC dysfunction and improve PDT outcome. Epigenetic reversal agents can increase tumor expression of MHC class I and also simultaneously increase expression of tumor antigens. A few clinical reports have shown that anti-tumor immunity can be generated by PDT in patients, and it is hoped that these combination approaches may increase tumor cures in patients. PMID:26062987

  10. IL-2/neuroantigen fusion proteins as antigen-specific tolerogens in experimental autoimmune encephalomyelitis (EAE): correlation of T cell-mediated antigen presentation and tolerance induction.

    Science.gov (United States)

    Mannie, Mark D; Clayson, Barbara A; Buskirk, Elizabeth J; DeVine, Jarret L; Hernandez, Jose J; Abbott, Derek J

    2007-03-01

    The purpose of this study was to assess whether the Ag-targeting activity of cytokine/neuroantigen (NAg) fusion proteins may be associated with mechanisms of tolerance induction. To assess this question, we expressed fusion proteins comprised of a N-terminal cytokine domain and a C-terminal NAg domain. The cytokine domain comprised either rat IL-2 or IL-4, and the NAg domain comprised the dominant encephalitogenic determinant of the guinea pig myelin basic protein. Subcutaneous administration of IL2NAg (IL-2/NAg fusion protein) into Lewis rats either before or after an encephalitogenic challenge resulted in an attenuated course of experimental autoimmune encephalomyelitis. In contrast, parallel treatment of rats with IL4NAg (IL-4/NAg fusion protein) or NAg lacked tolerogenic activity. In the presence of IL-2R(+) MHC class II(+) T cells, IL2NAg fusion proteins were at least 1,000 times more potent as an Ag than NAg alone. The tolerogenic activity of IL2NAg in vivo and the enhanced potency in vitro were both dependent upon covalent linkage of IL-2 and NAg. IL4NAg also exhibited enhanced antigenic potency. IL4NAg was approximately 100-fold more active than NAg alone in the presence of splenic APC. The enhanced potency of IL4NAg also required covalent linkage of cytokine and NAg and was blocked by soluble IL-4 or by a mAb specific for IL-4. Other control cytokine/NAg fusion proteins did not exhibit a similar enhancement of Ag potency compared with NAg alone. Thus, the IL2NAg and IL4NAg fusion proteins targeted NAg for enhanced presentation by particular subsets of APC. The activities of IL2NAg revealed a potential relationship between NAg targeting to activated T cells, T cell-mediated Ag presentation, and tolerance induction.

  11. Silibinin prevents prostate cancer cell-mediated differentiation of naïve fibroblasts into cancer-associated fibroblast phenotype by targeting TGF β2.

    Science.gov (United States)

    Ting, Harold J; Deep, Gagan; Jain, Anil K; Cimic, Adela; Sirintrapun, Joseph; Romero, Lina M; Cramer, Scott D; Agarwal, Chapla; Agarwal, Rajesh

    2015-09-01

    Tumor microenvironment (TM) is an essential element in prostate cancer (PCA), offering unique opportunities for its prevention. TM includes naïve fibroblasts that are recruited by nascent neoplastic lesion and altered into 'cancer-associated fibroblasts' (CAFs) that promote PCA. A better understanding and targeting of interaction between PCA cells and fibroblasts and inhibiting CAF phenotype through non-toxic agents are novel approaches to prevent PCA progression. One well-studied cancer chemopreventive agent is silibinin, and thus, we examined its efficacy against PCA cells-mediated differentiation of naïve fibroblasts into a myofibroblastic-phenotype similar to that found in CAFs. Silibinin's direct inhibitory effect on the phenotype of CAFs derived directly from PCA patients was also assessed. Human prostate stromal cells (PrSCs) exposed to control conditioned media (CCM) from human PCA PC3 cells showed more invasiveness, with increased alpha-smooth muscle actin (α-SMA) and vimentin expression, and differentiation into a phenotype we identified in CAFs. Importantly, silibinin (at physiologically achievable concentrations) inhibited α-SMA expression and invasiveness in differentiated fibroblasts and prostate CAFs directly, as well as indirectly by targeting PCA cells. The observed increase in α-SMA and CAF-like phenotype was transforming growth factor (TGF) β2 dependent, which was strongly inhibited by silibinin. Furthermore, induction of α-SMA and CAF phenotype by CCM were also strongly inhibited by a TGFβ2-neutralizing antibody. The inhibitory effect of silibinin on TGFβ2 expression and CAF-like biomarkers was also observed in PC3 tumors. Together, these findings highlight the potential usefulness of silibinin in PCA prevention through targeting the CAF phenotype in the prostate TM. © 2014 Wiley Periodicals, Inc.

  12. 21 Days head-down bed rest induces weakening of cell-mediated immunity - Some spaceflight findings confirmed in a ground-based analog.

    Science.gov (United States)

    Kelsen, Jens; Bartels, Lars Erik; Dige, Anders; Hvas, Christian Lodberg; Frings-Meuthen, Petra; Boehme, Gisela; Thomsen, Marianne Kragh; Fenger-Grøn, Morten; Dahlerup, Jens Frederik

    2012-08-01

    Several studies indicate a weakening of cell-mediated immunity (CMI) and reactivation of latent herpes viruses during spaceflight. We tested the hypothesis that head-down bed rest (HDBR), a ground-based analog of spaceflight, mimics the impact of microgravity on human immunity. Seven healthy young males underwent two periods of 3 weeks HDBR in the test facility of the German Aerospace Center. As a nutritional countermeasure aimed against bone demineralisation, 90 mmol potassium bicarbonate (KHCO(3)) was administered daily in a crossover design. Blood samples were drawn on five occasions. Whole blood was stimulated with antigen i.e. Candida albicans, purified protein derivative (PPD) tuberculin, tetanus toxoid and Cytomegalovirus (CMV) (CMV-QuantiFERON). Flow cytometric analysis included CD4(+)CD25(+)CD127(-)FOXP3(+) regulatory T cells (Tregs), γδ T cells, B cells, NK cells and dendritic cells. In one of the two bed rest periods, we observed a significant decrease in production of interleukin-2 (IL-2), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) following phytohemagglutinin (PHA) stimulation, with a rapid normalization being observed after HDBR. The cytokine levels showed a V-shaped pattern that led to a relativeTh2-shift in cytokine balance. Only three individuals responded to the specific T cell antigens without showing signs of an altered response during HDBR, nor did we observe reactivation of CMV or Epstein-Barr virus (EBV). Of unknown significance, dietary supplementation with KHCO(3) counteracted the decrease in IL-2 levels during HDBR, while there was no impact on other immunological parameters. We conclude that discrete alterations in CMI may be induced by HDBR in selected individuals. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. CCR5 Antagonist TD-0680 Uses a Novel Mechanism for Enhanced Potency against HIV-1 Entry, Cell-mediated Infection, and a Resistant Variant*

    Science.gov (United States)

    Kang, Yuanxi; Wu, Zhiwei; Lau, Terrence C. K.; Lu, Xiaofan; Liu, Li; Cheung, Allen K. L.; Tan, Zhiwu; Ng, Jenny; Liang, Jianguo; Wang, Haibo; Li, Saikam; Zheng, Bojian; Li, Ben; Chen, Li; Chen, Zhiwei

    2012-01-01

    Regardless of the route of transmission, R5-tropic HIV-1 predominates early in infection, rendering C-C chemokine receptor type 5 (CCR5) antagonists as attractive agents not only for antiretroviral therapy but also for prevention. Here, we report the specificity, potency, and underlying mechanism of action of a novel small molecule CCR5 antagonist, TD-0680. TD-0680 displayed the greatest potency against a diverse group of R5-tropic HIV-1 and SIV strains when compared with its prodrug, TD-0232, the Food and Drug Administration-approved CCR5 antagonist Maraviroc, and TAK-779, with EC50 values in the subnanomolar range (0.09–2.29 nm). Importantly, TD-0680 was equally potent at blocking envelope-mediated cell-cell fusion and cell-mediated viral transmission as well as the replication of a TAK-779/Maraviroc-resistant HIV-1 variant. Interestingly, TD-0232 and TD-0680 functioned differently despite binding to a similar transmembrane pocket of CCR5. Site-directed mutagenesis, drug combination, and antibody blocking assays identified a novel mechanism of action of TD-0680. In addition to binding to the transmembrane pocket, the unique exo configuration of this molecule protrudes and sterically blocks access to the extracellular loop 2 (ECL2) region of CCR5, thereby interrupting the interaction between virus and its co-receptor more effectively. This mechanism of action was supported by the observations of similar TD-0680 potency against CD4-dependent and -independent SIV strains and by molecular docking analysis using a CCR5 model. TD-0680, therefore, merits development as an anti-HIV-1 agent for therapeutic purposes and/or as a topical microbicide for the prevention of sexual transmission of R5-tropic HIV-1. PMID:22447925

  14. Novel cytotoxic phenanthrenequinone from Odontioda Marie Noel 'Velano'.

    Science.gov (United States)

    Masuda, Yuko; Suzuki, Ryuichiro; Sakagami, Hiroshi; Umemura, Naoki; Shirataki, Yoshiaki

    2012-01-01

    A new phenanthrenequinone, 5-hydroxy-2,3-dimethoxy-1,4-phenanthrenequinone (1), was isolated along with a known 9,10-dihydrophenanthrenequinone, ephemeranthoquinone B (2) from an MeOH extract of Odontioda Marie Noel 'Velano' through bioassay-guided fractionation. Their structures were elucidated by spectroscopic analysis, and the compounds were tested for in vitro cytotoxic activity. The compounds showed slightly higher cytotoxicity in human oral squamous cell carcinoma and leukemic cell lines as compared with human oral normal cells. The results suggest that apoptosis may not be involved in the cytotoxicity induction.

  15. Cytotoxicity study of dimethylisatin and its heterocyclic derivatives

    Directory of Open Access Journals (Sweden)

    Mohammad Mamun Hossain

    2007-06-01

    Full Text Available Isatin derivatives are bioactive molecules. To study the cytotoxicity and eventually the anticancer activities against cancer cell lines, a series of dimethyl-substitituted isatin derivatives (4-8 starting from isatin thiosemicarbazones (3 had been synthesized in high yields. Investigation of the cytotoxicity of these compounds was carried out against brine shrimp by lethality bioassay. The present study shows that compounds 4, 5, 6 and 8/ with heterocyclic moiety had pronounced cytotoxicity whereas 7, 7/ and 8 were moderately active. It is remarkable that the substituent, X = -OCH3 has greater activity than the bromine atom in this series.

  16. Cytotoxicity of dental casting alloys pretreated with biologic solutions.

    Science.gov (United States)

    Nelson, S K; Wataha, J C; Neme, A M; Cibirka, R M; Lockwood, P E

    1999-05-01

    Short-term (72-168 hours) in vitro tests are used to evaluate the cytotoxicity of dental casting alloys. The ability of these short-term tests to predict long-term in vivo cytotoxicity has been questioned. A procedure to accelerate the testing of casting alloys would be useful in predicting longer-term alloy cytotoxicity. This study hypothesized that preconditioning casting alloys by soaking in a biologic liquid would change subsequent cytotoxicity by removing some elements. Preconditioning may be 1 method of accelerating short-term in vitro tests. Dental casting alloys were exposed to either saline, cell culture medium, or a saline/bovine serum albumin (BSA) solution for 72 hours before standard in vitro cytotoxicity testing. Six types of alloys were tested (n = 6): 5 Au-Ag-Cu-Pd alloys (single phase) and 1 Ag-Pd-Cu alloy (multiple phase). Teflon (Tf) samples served as a control. After preconditioning, alloys were placed in direct contact with Balb/c fibroblasts for 72 hours, after which cell viability was measured by succinic dehydrogenase activity (MTT method) relative to Tf controls (100% = no toxicity). Elements released into the preconditioning solutions were measured by atomic absorption spectroscopy. Cytotoxicities of preconditioned alloys and amounts of elemental release were compared with unconditioned alloys. A preconditioning time of 72 hours was sufficient to change the cytotoxicity of the tested alloys. The alloys that were more cytotoxic initially became less cytotoxic after preconditioning. For all the alloys tested, except the Ag-Pd-Cu multiphase alloy, preconditioning with either the saline or the saline/BSA solution caused an increase in cellular activity, therefore the preconditioned alloys were less cytotoxic. The cell culture medium preconditioning solution had a variable effect, causing increased or decreased cellular activity depending on the alloy treated. Preconditioning of casting alloys decreased subsequent cytotoxicity. However, not all

  17. Assay of mast cell mediators

    DEFF Research Database (Denmark)

    Rådinger, Madeleine; Jensen, Bettina M; Swindle, Emily

    2015-01-01

    Mediator release from activated mast cells is a major initiator of the symptomology associated with allergic disorders such as anaphylaxis and asthma. Thus, methods to monitor the generation and release of such mediators have widespread applicability in studies designed to understand the processes...... regulating mast cell activation and for the identification of therapeutic approaches to block mast cell-driven disease. In this chapter, we discuss approaches used for the determination of mast cell degranulation, lipid-derived inflammatory mediator production, and cytokine/chemokine gene expression as well...

  18. "False" cytotoxicity of ions-adsorbing hydroxyapatite - Corrected method of cytotoxicity evaluation for ceramics of high specific surface area.

    Science.gov (United States)

    Klimek, Katarzyna; Belcarz, Anna; Pazik, Robert; Sobierajska, Paulina; Han, Tomasz; Wiglusz, Rafal J; Ginalska, Grazyna

    2016-08-01

    An assessment of biomaterial cytotoxicity is a prerequisite for evaluation of its clinical potential. A material is considered toxic while the cell viability decreases under 70% of the control. However, extracts of certain materials are likely to reduce the cell viability due to the intense ions adsorption from culture medium (e.g. highly bioactive ceramics of high surface area). Thus, the standard ISO 10993-5 procedure is inappropriate for cytotoxicity evaluation of ceramics of high specific surface area because biomaterial extract obtained in this method (ions-depleted medium) is not optimal for cell cultures per se. Therefore, a simple test was designed as an alternative to ISO 10993-5 standard for cytotoxicity evaluation of the biomaterials of high surface area and high ions absorption capacity. The method, presented in this paper, included the evaluation of ceramics extract prepared according to corrected procedure. The corrected extract was found not cytotoxic (cell viability above 70%), suggesting that modified method for cytotoxicity evaluation of ions-adsorbing ceramics is more appropriate than ISO 10993-5 standard. For such biomaterials, the term "false" cytotoxicity is more suitable. Moreover, it was noted that NRU assay and microscopic observations should be recommended for cytotoxicity evaluation of ceramics of high surface area. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. 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

  20. 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.

  1. 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.

  2. Genotoxic monitoring of nurses handling cytotoxic drugs

    Directory of Open Access Journals (Sweden)

    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.

  3. Cytotoxicity and ion release of alloy nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Anne [Laser Zentrum Hannover e.V (Germany); Fuhlrott, Jutta; Loos, Anneke [Hannover Medical School, Biovertraeglichkeitslabor BioMedimplant (Germany); Barcikowski, Stephan, E-mail: stephan.barcikowski@uni-due.de [Laser Zentrum Hannover e.V (Germany)

    2012-01-15

    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 {mu}M. 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. Enhanced CDC of B cell chronic lymphocytic leukemia cells mediated by rituximab combined with a novel anti-complement factor H antibody.

    Directory of Open Access Journals (Sweden)

    Mark T Winkler

    Full Text Available Rituximab therapy for B cell chronic lymphocytic leukemia (B-CLL has met with mixed success. Among several factors to which resistance can be attributed is failure to activate complement dependent cytotoxicity (CDC due to protective complement regulatory proteins, including the soluble regulator complement factor H (CFH. We hypothesized that rituximab killing of non-responsive B-CLL cells could be augmented by a novel human monoclonal antibody against CFH. The B cells from 11 patients with B-CLL were tested ex vivo in CDC assays with combinations of CFH monoclonal antibody, rituximab, and a negative control antibody. CDC of rituximab non-responsive malignant B cells from CLL patients could in some cases be augmented by the CFH monoclonal antibody. Antibody-mediated cytotoxicity of cells was dependent upon functional complement. In one case where B-CLL cells were refractory to CDC by the combination of rituximab plus CFH monoclonal antibody, additionally neutralizing the membrane complement regulatory protein CD59 allowed CDC to occur. Inhibiting CDC regulatory proteins such as CFH holds promise for overcoming resistance to rituximab therapy in B-CLL.

  5. Comparative Measurement of In Vitro T-2 Toxin Cytotoxicity using Three Different Cytotoxicity Assays.

    Science.gov (United States)

    Heidari, Mahnaz; Ghazi-Khansari, Mahmmoud; Khoshnoodi, Jalal; Shokri, Fazel

    2003-01-01

    T-2 toxin is a secondary fungal metabolite produced by various species of fusarium. In this study, the in vitro cytotoxicity of T-2 toxin in the human hepatoma cell line (HepG2) was determined using three methods, including neutral red dye adsorption, trypan blue dye exclusion, and uptake of radiolabeled 3 H-thymidine. The 50% lethal concentration of T-2 toxin was found to be similar for all three, accounting for 2.39, 2.96, and 3.44 ng/mL, respectively, as determined by these assays. Significant correlations were also observed among the three methods (p objectivity.

  6. Heterogeneity of Human Breast Cancer Cell Clones with respect to Cytotoxic Susceptibility detected by Cytotoxic T-Lymphocytes and Natural Killer Cells

    OpenAIRE

    Sato, Takashi; Sato, Noriyuki; Cho, Junmin; Takahashi, Shuji; Toda, Kazunori; Asaishi, Kazuaki; Hirata, Koichi; Kikuchi, Kokichi

    1991-01-01

    Clonal heterogeneity of human breast cancer cells, HMC-1, with respect to the cytotoxic susceptibility against autologous cytotoxic T-lymphocytes (CTL), TcHMC-1, and natural killer- (NK) cells was demonstrated in a ??Cr release cytotoxicity assay. We have established 8 tumor cell clones, HMC-1-1 through HMC-1-8, from HMC-1 cells and autologous TcHMC-1 clone that showed high cytotoxic activity as well. In the cytotoxicity assays, HMC-1-8 clone showed significantly high cytotoxic susceptibility...

  7. A novel synthesis and preliminary in vitro cytotoxic evaluation of ...

    Indian Academy of Sciences (India)

    /fulltext/jcsc/129/02/0249-0258. Keywords. Triflic anhydride; Boc anhydride; Negishi coupling; acid-amine coupling; cyclization reaction; cytotoxicity; MCF-7. Abstract. We report the synthesis and characterization of four new compounds: ...

  8. 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 ...

  9. Antibacterial and cytotoxic compounds from the bark of Cananga odorata.

    Science.gov (United States)

    Rahman, M Mukhlesur; Lopa, Simin S; Sadik, Golam; Harun-Or-Rashid; Islam, Robiul; Khondkar, Proma; Alam, A H M Khurshid; Rashid, Mohammad A

    2005-12-01

    O-Methylmoschatoline, liriodenine and 3,4-dihydroxybenzoic acid isolated from the barks of Cananga odorata showed antibacterial activities against a number of Gram (+) and Gram (-) bacteria. The compounds also showed antifungal and cytotoxic activities.

  10. Antibacterial, Cytotoxic and Antioxidant Potential of Vitex Negundo ...

    African Journals Online (AJOL)

    Ciocalteau reagent and Aluminium chloride colorimetric estimation method respectively. Negundoside and agnuside content were estimated using HPLC. Antibacterial activity of both the extracts was tested by Agar well diffusion assay. Cytotoxicity ...

  11. 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...

  12. In vitro Cytotoxic and Antioxidant Activity of Leaf Extracts of ...

    African Journals Online (AJOL)

    In vitro Cytotoxic and Antioxidant Activity of Leaf Extracts of Mangrove Plant, Phoenix paludosa Roxb. Sameera R. Samarakoon, Chanthirika Shanmuganathan, Meran K. Ediriweera, Kamani H. Tennekoon, Poorna Piyathilaka, Ira Thabrew, E Dilip de Silva ...

  13. Phytochemical Analysis and Cytotoxicity Evaluation of Kelussia odoratissima Mozaff.

    Directory of Open Access Journals (Sweden)

    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.

  14. In vitro antifungal and cytotoxicity activities of selected Tanzanian ...

    African Journals Online (AJOL)

    Purpose: To evaluate the antifungal and cytotoxic activities of four medicinal plants from Tanzania, namely, Mystroxylon aethiopicum, Lonchocarpus capassa, Albizia anthelmentica and Myrica salicifolia. Methods: The plant materials were subjected to extraction using dichloromethane, ethyl acetate and distilled water.

  15. Cytotoxic effects of delfin insecticide ( Bacillus thuringiensis ) on cell ...

    African Journals Online (AJOL)

    Cytotoxic effects of delfin insecticide ( Bacillus thuringiensis ) on cell behaviour, phagocytosis, contractile vacuole activity and macronucleus in a protozoan ciliate Paramecium caudatum. ... macronucleus, fragmentation, vacuolization and complete diffusion of macronucleus were observed and were dose dependent.

  16. Comparing the cytotoxicity of electronic cigarette fluids, aerosols and solvents.

    Science.gov (United States)

    Behar, Rachel Z; Wang, Yuhuan; Talbot, Prue

    2017-06-08

    As thousands of electronic cigarette (e-cigarette) refill fluids continue to be formulated and distributed, there is a growing need to understand the cytotoxicity of the flavouring chemicals and solvents used in these products to ensure they are safe. The purpose of this study was to compare the cytotoxicity of e-cigarette refill fluids/solvents and their corresponding aerosols using in vitro cultured cells. E-cigarette refill fluids and do-it-yourself products were screened in liquid and aerosol form for cytotoxicity using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The sensitivity of human pulmonary fibroblasts, lung epithelial cells (A549) and human embryonic stem cells to liquids and aerosols was compared. Aerosols were produced using Johnson Creek's Vea cartomizer style e-cigarette. A hierarchy of potency was established for the aerosolised products. Our data show that (1) e-cigarette aerosols can produce cytotoxic effects in cultured cells, (2) four patterns of cytotoxicity were found when comparing refill fluids and their corresponding aerosols, (3) fluids accurately predicted aerosol cytotoxicity 74% of the time, (4) stem cells were often more sensitive to aerosols than differentiated cells and (5) 91% of the aerosols made from refill fluids containing only glycerin were cytotoxic, even when produced at a low voltage. Our data show that various flavours/brands of e-cigarette refill fluids and their aerosols are cytotoxic and demonstrate the need for further evaluation of e-cigarette products to better understand their potential health effects. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  17. Novel Cytotoxic Phenanthrenequinone from Odontioda Marie Noel ‘Velano’

    OpenAIRE

    増田, 裕子; 鈴木, 龍一郎; 坂上, 宏; Umemura, Naoki; 白瀧, 義明

    2012-01-01

    A new phenanthrenequinone, 5-hydroxy-2,3-dimethoxy-1,4-phenanthrenequinone (1), was isolated along with a known 9,10-dihydrophenanthrenequinone, ephemeranthoquinone B (2) from an MeOH extract of Odontioda Marie Noel ‘Velano’ through bioassay-guided fractionation. Their structures were elucidated by spectroscopic analysis, and the compounds were tested for in vitro cytotoxic activity. The compounds showed slightly higher cytotoxicity in human oral squamous cell carcinoma and leukemic cell line...

  18. Effect of Cytotoxicity of Pegylated Liposomal Recombinant Human ...

    African Journals Online (AJOL)

    The difference in cytotoxicity between the free drug (IC50 = 110.1 ± 3.1 μg/ml) and nanodrug (IC50 = 87.2 ± 2.3 μg/ml) was statistically significant (p ˂ 0.05). Conclusion: This study shows that pegylated nanoliposomal rHuEPO has a powerful cytotoxic effect on SH-SY5Y cell line and is therefore a suitable alternative to the ...

  19. Extravasational side effects of cytotoxic drugs: A preventable catastrophe

    OpenAIRE

    Thakur, Jagdeep S.; Chauhan, C. G. S.; Diwana, Vijay K.; Chauhan, Dayal C.; Thakur, Anamika

    2008-01-01

    In addition to their therapeutic effects on malignant cells, cytotoxic agents have the potential of causing destruction of healthy, normal cells. Extravasation of the drug can produce extensive necrosis of the skin and subcutaneous tissue. Management of these extravasational effects differs from one centre to another and prevention is usually strongly emphasized. We analyzed our management of 12 patients referred to us over five years with extravasation of cytotoxic drugs and reviewed the lit...

  20. Propofol Enhances Hemoglobin-Induced Cytotoxicity in Neurons.

    Science.gov (United States)

    Yuan, Jing; Cui, Guiyun; Li, Wenlu; Zhang, Xiaoli; Wang, Xiaoying; Zheng, Hui; Zhang, Jian; Xiang, Shuanglin; Xie, Zhongcong

    2016-04-01

    It has been increasingly suggested that propofol protects against hypoxic-/ischemic-induced neuronal injury. As evidenced by hemorrhage-induced stroke, hemorrhage into the brain may also cause brain damage. Whether propofol protects against hemorrhage-induced brain damage remains unknown. Therefore, in this study, we investigated the effects of propofol on hemoglobin-induced cytotoxicity in cultured mouse cortical neurons. Neurons were prepared from the cortex of embryonic 15-day-old mice. Hemoglobin was used to induce cytotoxicity in the neurons. The neurons were then treated with propofol for 4 hours. Cytotoxicity was determined by lactate dehydrogenase release assay. Caspase-3 activation was examined by Western blot analysis. Finally, the free radical scavenger U83836E was used to examine the potential involvement of oxidative stress in propofol's effects on hemoglobin-induced cytotoxicity. We found that treatment with hemoglobin induced cytotoxicity in the neurons. Propofol enhanced hemoglobin-induced cytotoxicity. Specifically, there was a significant difference in the amount of lactate dehydrogenase release between hemoglobin plus saline (19.84% ± 5.38%) and hemoglobin plus propofol (35.79% ± 4.41%) in mouse cortical neurons (P = 0.00058, Wilcoxon Mann-Whitney U test, n = 8 in the control group or the treatment group). U83836E did not attenuate the enhancing effects of propofol on hemoglobin-induced cytotoxicity in the neurons, and propofol did not significantly affect caspase-3 activation induced by hemoglobin. These data suggested that caspase-3 activation and oxidative stress might not be the underlying mechanisms by which propofol enhanced hemoglobin-induced cytotoxicity. Moreover, these data suggested that the neuroprotective effects of propofol would be dependent on the condition of the brain injury, which will need to be confirmed in future studies. These results from our current proof-of-concept study should promote more research in vitro and in