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Sample records for ab-dependent cell-mediated cytotoxicity

  1. Natural killer cell mediated cytotoxic responses in the Tasmanian devil.

    PubMed

    Brown, Gabriella K; Kreiss, Alexandre; Lyons, A Bruce; Woods, Gregory M

    2011-01-01

    The Tasmanian devil (Sarcophilus harrisii), the world's largest marsupial carnivore, is under threat of extinction following the emergence of an infectious cancer. Devil facial tumour disease (DFTD) is spread between Tasmanian devils during biting. The disease is consistently fatal and devils succumb without developing a protective immune response. The aim of this study was to determine if Tasmanian devils were capable of forming cytotoxic antitumour responses and develop antibodies against DFTD cells and foreign tumour cells. The two Tasmanian devils immunised with irradiated DFTD cells did not form cytotoxic or humoral responses against DFTD cells, even after multiple immunisations. However, following immunisation with xenogenic K562 cells, devils did produce cytotoxic responses and antibodies against this foreign tumour cell line. The cytotoxicity appeared to occur through the activity of natural killer (NK) cells in an antibody dependent manner. Classical NK cell responses, such as innate killing of DFTD and foreign cancer cells, were not observed. Cells with an NK-like phenotype comprised approximately 4 percent of peripheral blood mononuclear cells. The results of this study suggest that Tasmanian devils have NK cells with functional cytotoxic pathways. Although devil NK cells do not directly recognise DFTD cancer cells, the development of antibody dependent cell-mediated cytotoxicity presents a potential pathway to induce cytotoxic responses against the disease. These findings have positive implications for future DFTD vaccine research. PMID:21957452

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

    PubMed Central

    Rajasekaran, Narendiran; Chester, Cariad; Yonezawa, Atsushi; Zhao, Xing; Kohrt, Holbrook E

    2015-01-01

    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.

  3. Antibody-Dependent Cell-Mediated Cytotoxicity to Hemagglutinin of Influenza A Viruses After Influenza Vaccination in Humans

    PubMed Central

    Zhong, Weimin; Liu, Feng; Wilson, Jason R.; Holiday, Crystal; Li, Zhu-Nan; Bai, Yaohui; Tzeng, Wen-Pin; Stevens, James; York, Ian A.; Levine, Min Z.

    2016-01-01

    Background. Detection of neutralizing antibodies (nAbs) to influenza A virus hemagglutinin (HA) antigens by conventional serological assays is currently the main immune correlate of protection for influenza vaccines However, current prepandemic avian influenza vaccines are poorly immunogenic in inducing nAbs despite considerable protection conferred. Recent studies show that Ab-dependent cell-mediated cytotoxicity (ADCC) to HA antigens are readily detectable in the sera of healthy individuals and patients with influenza infection. Methods. Virus neutralization and ADCC activities of serum samples from individuals who received either seasonal or a stock-piled H5N1 avian influenza vaccine were evaluated by hemagglutination inhibition assay, microneutralization assay, and an improved ADCC natural killer (NK) cell activation assay. Results. Immunization with inactivated seasonal influenza vaccine led to strong expansion of both nAbs and ADCC-mediating antibodies (adccAbs) to H3 antigen of the vaccine virus in 24 postvaccination human sera. In sharp contrast, 18 individuals vaccinated with the adjuvanted H5N1 avian influenza vaccine mounted H5-specific antibodies with strong ADCC activities despite moderate virus neutralization capacity. Strength of HA-specific ADCC activities is largely associated with the titers of HA-binding antibodies and not with the fine antigenic specificity of anti-HA nAbs. Conclusions. Detection of both nAbs and adccAbs may better reflect protective capacity of HA-specific antibodies induced by avian influenza vaccines.

  4. A rapid and sensitive fluorometric microassay for determining cell mediated cytotoxicity to adherent growing cell lines.

    PubMed

    Krüger-Krasagakes, S; Garbe, C; Kossman, P; Orfanos, C E

    1992-11-25

    In order to measure cell mediated cytotoxicity to adherent growing cell lines in vitro more rapidly and conveniently, a fluorometric microassay was developed and results were compared with those obtained by the 51Cr release assay. The fluorometric method is based on the hydrolysis of the fluorochrome 4-methylumbelliferyl heptanoate (MUH) by intracellular esterases of viable cells. Melanoma cell monolayers were incubated with lymphokine activated killer (LAK) cells for 4 h at various effector: target (E:T) cell ratios (E:T = 16, 8, 4, 2:1). Thereafter surviving adherent melanoma cells were stained with MUH for 30 min and fluorescence was measured directly in a 96 well plate reader. For the calculation of LAK cell cytotoxicity fluorescence values were corrected for the number of nonspecifically detached tumor cells during the washes and the number of nonspecifically adherent LAK cells. Using identical target and effector cell preparations both assays showed a nearly proportional increase of percentage cytotoxicity with rising numbers of lymphocytes. Compared with the 51Cr release assay, however, higher cytotoxicity values were obtained with the fluorometric MUH microassay: 57% with MUH versus 26% with 51Cr and 39% versus 14% for cell lines StML-11 and SKMel-28, respectively (E:T ratio = 16:1). The higher cytotoxicity rates obtained with the fluorometric MUH microassay were not due to the additional 30 min staining with MUH or due to nonspecific hydrolysis of MUH by extracellular esterases released from damaged cells, as could be shown by a series of experiments. In conclusion, a simple and rapid fluorometric microassay has been developed showing reliable reproducibility and a higher sensitivity compared with the 51Cr release assay for the determination of cellular cytotoxicity to adherent growing cell lines, avoiding hazardous radioactive labels. PMID:1431156

  5. Compromised NK Cell-Mediated Antibody-Dependent Cellular Cytotoxicity in Chronic SIV/SHIV Infection

    PubMed Central

    He, Xuan; Li, Dan; Luo, Zhenwu; Liang, Hua; Peng, Hong; Zhao, Yangyang; Wang, Nidan; Liu, Donghua; Qin, Chuan; Wei, Qiang; Yan, Huimin; Shao, Yiming

    2013-01-01

    Increasing evidence indicates that antibody-dependent cellular cytotoxicity (ADCC) contributes to the control of HIV/SIV infection. However, little is known about the ADCC function of natural killer (NK) cells in non-human primate model. Here we demonstrated that ADCC function of NK cells was significantly compromised in chronic SIV/SHIV infection, correlating closely with the expression of FcγRIIIa receptor (CD16) on NK cells. CD32, another class of IgG Fc receptors, was identified on NK cells with higher expression in the infected macaques and the blockade of CD32 impacted the ability of NK cells to respond to antibody-coated target cells. The inhibition of matrix metalloproteases (MMPs), a group of enzymes normally involved in tissue/receptor remodeling, could restore NK cell-mediated ADCC with increased CD16 expression on macaque NK cells. These data offer a clearer understanding of NK cell-mediated ADCC in rhesus macaques, which will allow us to evaluate the ADCC repertoire arising from preclinical vaccination studies in non-human primates and inform us in the future design of effective HIV vaccination strategies. PMID:23424655

  6. Kinetics of cell-mediated cytotoxicity in mice fed diets of various fat contents.

    PubMed

    Olson, L M; Visek, W J

    1990-06-01

    We previously reported lower mitogen-induced blastogenic and cytotoxic activity of splenocytes from C3H/OUJ female mice fed 20% soybean oil (SBO) in their diet compared to those fed 5% SBO. The present study examined the kinetics of cell-mediated cytotoxicity using the same animal model and dietary treatments. Kinetic parameters were determined by analyzing the lytic efficiency of splenocytes cultured for various times with several concentrations of radiolabeled P815 mastocytoma cells. The apparent avidity constant (K1/2) of the reaction was not changed by dietary SBO intake (1.0 +/- 0.2 x 10(5) cells for 20% SBO versus 1.3 +/- 0.3 x 10(5) cells for 5% SBO). However, the maximum velocity (Vmax) of the reaction for splenocytes from mice fed 20% SBO was significantly lower than that for splenocytes from mice fed 5% SBO (1.4 +/- 0.2 x 10(4) cells/h for 20% SBO versus 2.3 +/- 0.4 x 10(4) cells/h for 5% SBO, p less than 0.05). The evidence indicates that the rate of target cell lysis, but not the avidity of the lymphocytes for the target cell antigen, was altered by increasing dietary SBO concentration. PMID:2352036

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

    PubMed Central

    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

  8. Cell-mediated cytotoxicity-supporting activity of various human gammaglobulin preparations.

    PubMed

    Wakiguchi, H; Fujieda, M; Matsumoto, K; Ohara, Y; Kuroiwa, Y; Wakiguchi, A; Shiraishi, T; Oda, M; Kurashige, T; Kitamura, I

    1987-04-01

    Antibody activity, especially that involved in the reaction of antibody-dependent cell-mediated cytotoxicity (ADCC), of five commercially available human gammaglobulin preparations (standard, pepsin-treated, plasmin-treated, polyethylene glycol-fractionated and S-sulfonated gammaglobulin) was measured. All these gammaglobulin preparations had high titers of hemagglutination inhibition and neutralizing antibody against measles virus. In ADCC reaction, the pepsin-treated gammaglobulin preparation showed no antibody activity. The standard gammaglobulin preparation showed weak activity only when highly diluted. The remaining three preparations showed high activity. Though the S-sulfonated gammaglobulin preparation showed no activity in ADCC reaction, it showed high activity after reconversion by means of oxidation and reduction in vitro. The plasmin-treated gammaglobulin preparation showed greater activity than the polyethylene glycol-fractionated preparation of the optimal concentration. In ADCC tests using the plasmin-treated gammaglobulin preparation, K cell activity was strongly inhibited by Hg (thimerosal), while, in those using the standard gammaglobulin preparation, the activity was hardly influenced by Hg, suggesting that the low ADCC activity of the standard gammaglobulin preparation of high concentrations was due to the inhibitory effect of aggregated immunoglobulin G molecules. PMID:2438903

  9. Systemic induction of cells mediating antibody-dependent cellular cytotoxicity following administration of interleukin 2.

    PubMed

    Eisenthal, A; Rosenberg, S A

    1989-12-15

    We have previously demonstrated that incubation of murine cells in vitro in interleukin 2 (IL-2) induced antibody-dependent cellular cytotoxicity (ADCC) and that these cells were derived from the NK/LAK, FcR+ cell population. In the present study we show that in vivo administration of IL-2 to mice induces cells which exhibit ADCC activity in the peritoneal cavity, liver, lungs, and to a lesser degree in the bone marrow, spleen, mesenteric lymph nodes, and thymus. A gradual increase in ADCC activity and the number of Fc-receptor-positive cells was seen 1 to 3 days after starting IL-2 treatment. The cells mediating ADCC are closely related to LAK cells since they expressed Thy1.2 antigens and are derived from asialo GM1-positive, Lyt2/L3T4-negative, radiosensitive cells. These results demonstrate that IL-2 can systemically induce cells with ADCC activity and that this ability may be useful in the establishment of therapeutic models against disseminated cancer when combined with specific antitumor monoclonal antibodies. PMID:2573425

  10. [Progress of study on antitumor effects of antibody dependent cell mediated cytotoxicity--review].

    PubMed

    Qu, Yu-Hua; Li, Yang

    2010-10-01

    In recent years, as increasing of monoclonal antibody application in clinic, the antitumor effect of antibody dependent cell-mediated cytotoxicity (ADCC) get increasing attention. The natural killer (NK) cells are the most important effector cells mediating specific antitumor of ADCC; the phagocytes, T-cells and granulocytes have the definite effect on antitumor of ADCC. ADCC is confirmed as the important mechanism and means for clinically treating the cancers with monoclonal antibodies. The IgG antibody firstly combines with target cells (tumor cells) through antigen-binding sites, and then FcγR on effector cells identifies its Fc fragment and mediates ADCC. Today many kinds of monoclonal antibodies have been put into clinical application such as rituximab and other new anti-CD20 monoclonal antibodies including trastuzumab, erbitux, cetuximab, edrecolomab, nimotuzumab, gemtuzumab ozogamicin and so on, which all can mediate ADCC. The antitumor effects of ADCC mediated by monoclonal antibody can be influenced by IgG Fc receptor gene polymorphism, tumor cell antigen, serum antibody levels, cytokines and drugs etc. As to peripheral blood mononuclear cells, ADCC efficacies of FcγRIIIa-158V/V and FcγRIIa-131H/H are higher than that of other genotypes, while increasing the level of tumor antigen and decreasing the level of serum antibody or adding some cytokines (IL-2, IL-21, IL-15, etc) may elevate the ADCC effect mediated by monoclonal antibodies. Avoiding use of certain drugs (dexamethasone, TNF antagonist) or appropriately using of ondansetron and clemastine also can enhance the anti-tumor effect of ADCC mediated by monoclonal antibodies. In short, ADCC is very important in clinical application for anti-tumor treatment, but its efficacy may be impacted by multiple factors.In this article, the killing mechanisms of ADCC, the clinical use of monoclonal antibodies with antitumor effect of ADCC, the factors influencing anti-tumor efficacy of ADCC, and the antitumor

  11. A Neutralizing Antibody Assay Based on a Reporter of Antibody-Dependent Cell-Mediated Cytotoxicity.

    PubMed

    Wu, Yuling; Li, Jia J; Kim, Hyun Jun; Liu, Xu; Liu, Weiyi; Akhgar, Ahmad; Bowen, Michael A; Spitz, Susan; Jiang, Xu-Rong; Roskos, Lorin K; White, Wendy I

    2015-11-01

    Benralizumab is a humanized anti-IL5 receptor α (IL5Rα) monoclonal antibody (mAb) with enhanced (afucosylation) antibody-dependent cell-mediated cytotoxicity (ADCC) function. An ADCC reporter cell-based neutralizing antibody (NAb) assay was developed and characterized to detect NAb against benralizumab in human serum to support the clinical development of benralizumab. The optimal ratio of target cells to effector cells was 3:1. Neither parental benralizumab (fucosylated) nor benralizumab Fab resulted in ADCC activity, confirming the requirement for ADCC activity in the NAb assay. The serum tolerance of the cells was determined to be 2.5%. The cut point derived from normal and asthma serum samples was comparable. The effective range of benralizumab was determined, and 35 ng/mL [80% maximal effective concentration (EC80)] was chosen as the standard concentration to run in the assessment of NAb. An affinity purified goat anti-benralizumab polyclonal idiotype antibody preparation was shown to have NAb since it inhibited ADCC activity in a dose-dependent fashion. The low endogenous concentrations of IL5 and soluble IL5 receptor (sIL5R) did not demonstrate to interfere with the assay. The estimated assay sensitivities at the cut point were 1.02 and 1.10 μg/mL as determined by the surrogate neutralizing goat polyclonal and mouse monoclonal anti-drug antibody (ADA) controls, respectively. The assay can detect NAb (at 2.5 μg/mL) in the presence of 0.78 μg/mL benralizumab. The assay was not susceptible to non-specific matrix effects. This study provides an approach and feasibility of developing an ADCC cell-based NAb assay to support biopharmaceuticals with an ADCC function. PMID:26205082

  12. NK Cell-Mediated Antibody-Dependent Cellular Cytotoxicity in Cancer Immunotherapy

    PubMed Central

    Wang, Wei; Erbe, Amy K.; Hank, Jacquelyn A.; Morris, Zachary S.; Sondel, Paul M.

    2015-01-01

    Natural killer (NK) cells play a major role in cancer immunotherapies that involve tumor-antigen targeting by monoclonal antibodies (mAbs). NK cells express a variety of activating and inhibitory receptors that serve to regulate the function and activity of the cells. In the context of targeting cells, NK cells can be “specifically activated” through certain Fc receptors that are expressed on their cell surface. NK cells can express FcγRIIIA and/or FcγRIIC, which can bind to the Fc portion of immunoglobulins, transmitting activating signals within NK cells. Once activated through Fc receptors by antibodies bound to target cells, NK cells are able to lyse target cells without priming, and secrete cytokines like interferon gamma to recruit adaptive immune cells. This antibody-dependent cell-mediated cytotoxicity (ADCC) of tumor cells is utilized in the treatment of various cancers overexpressing unique antigens, such as neuroblastoma, breast cancer, B cell lymphoma, and others. NK cells also express a family of receptors called killer immunoglobulin-like receptors (KIRs), which regulate the function and response of NK cells toward target cells through their interaction with their cognate ligands that are expressed on tumor cells. Genetic polymorphisms in KIR and KIR-ligands, as well as FcγRs may influence NK cell responsiveness in conjunction with mAb immunotherapies. This review focuses on current therapeutic mAbs, different strategies to augment the anti-tumor efficacy of ADCC, and genotypic factors that may influence patient responses to antibody-dependent immunotherapies. PMID:26284063

  13. HER2-specific immunoligands engaging NKp30 or NKp80 trigger NK-cell-mediated lysis of tumor cells and enhance antibody-dependent cell-mediated cytotoxicity.

    PubMed

    Peipp, Matthias; Derer, Stefanie; Lohse, Stefan; Staudinger, Matthias; Klausz, Katja; Valerius, Thomas; Gramatzki, Martin; Kellner, Christian

    2015-10-13

    NK cells detect tumors through activating surface receptors, which bind self-antigens that are frequently expressed upon malignant transformation. To increase the recognition of tumor cells, the extracellular domains of ligands of the activating NK cell receptors NKp30, NKp80 and DNAM-1 (i.e. B7-H6, AICL and PVR, respectively) were fused to a single-chain fragment variable (scFv) targeting the human epidermal growth factor receptor 2 (HER2), which is displayed by various solid tumors. The resulting immunoligands, designated B7-H6:HER2-scFv, AICL:HER2-scFv, and PVR:HER2-scFv, respectively, bound HER2 and the addressed NK cell receptor. However, whereas B7-H6:HER2-scFv and AICL:HER2-scFv triggered NK cells to kill HER2-positive breast cancer cells at nanomolar concentrations, PVR:HER2-scFv was not efficacious. Moreover, NK cell cytotoxicity was enhanced synergistically when B7-H6:HER2-scFv or AICL:HER2-scFv were applied in combination with another HER2-specific immunoligand engaging the stimulatory receptor NKG2D. In contrast, no improvements were achieved by combining B7-H6:HER2-scFv with AICL:HER2-scFv. Additionally, B7-H6:HER2-scFv and AICL:HER2-scFv enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) by the therapeutic antibodies trastuzumab and cetuximab synergistically, with B7-H6:HER2-scFv exhibiting a higher efficacy. In summary, antibody-derived proteins engaging NKp30 or NKp80 may represent attractive biologics to further enhance anti-tumor NK cell responses and may provide an innovative approach to sensitize tumor cells for antibody-based immunotherapy. PMID:26392331

  14. HER2-specific immunoligands engaging NKp30 or NKp80 trigger NK-cell-mediated lysis of tumor cells and enhance antibody-dependent cell-mediated cytotoxicity

    PubMed Central

    Peipp, Matthias; Derer, Stefanie; Lohse, Stefan; Staudinger, Matthias; Klausz, Katja; Valerius, Thomas; Gramatzki, Martin; Kellner, Christian

    2015-01-01

    NK cells detect tumors through activating surface receptors, which bind self-antigens that are frequently expressed upon malignant transformation. To increase the recognition of tumor cells, the extracellular domains of ligands of the activating NK cell receptors NKp30, NKp80 and DNAM-1 (i.e. B7-H6, AICL and PVR, respectively) were fused to a single-chain fragment variable (scFv) targeting the human epidermal growth factor receptor 2 (HER2), which is displayed by various solid tumors. The resulting immunoligands, designated B7-H6:HER2-scFv, AICL:HER2-scFv, and PVR:HER2-scFv, respectively, bound HER2 and the addressed NK cell receptor. However, whereas B7-H6:HER2-scFv and AICL:HER2-scFv triggered NK cells to kill HER2-positive breast cancer cells at nanomolar concentrations, PVR:HER2-scFv was not efficacious. Moreover, NK cell cytotoxicity was enhanced synergistically when B7-H6:HER2-scFv or AICL:HER2-scFv were applied in combination with another HER2-specific immunoligand engaging the stimulatory receptor NKG2D. In contrast, no improvements were achieved by combining B7-H6:HER2-scFv with AICL:HER2-scFv. Additionally, B7-H6:HER2-scFv and AICL:HER2-scFv enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) by the therapeutic antibodies trastuzumab and cetuximab synergistically, with B7-H6:HER2-scFv exhibiting a higher efficacy. In summary, antibody-derived proteins engaging NKp30 or NKp80 may represent attractive biologics to further enhance anti-tumor NK cell responses and may provide an innovative approach to sensitize tumor cells for antibody-based immunotherapy. PMID:26392331

  15. Natural cell-mediated cytotoxicity against Candida albicans induced by cyclophosphamide: nature of the in vitro cytotoxic effector.

    PubMed Central

    Baccarini, M; Bistoni, F; Puccetti, P; Garaci, E

    1983-01-01

    We have recently reported the in vivo modulation of resistance to experimental Candida albicans infection by cyclophosphamide (150 mg/kg intraperitoneally) in mice and have shown that increased resistance to the microbial challenge occurs 12 to 21 days after treatment with the drug (Bistoni et al., Infect. Immun. 40: 46-55, 1983). The event is accompanied by the appearance of a highly candidacidal cell population in the spleen and the activation of a subpopulation of natural cytotoxic effectors reactive in vitro against YAC-1 tumor cells. We now provide evidence that these anti-YAC-1 cytotoxic effectors are clearly distinct from the cyclophosphamide-induced candidacidal effectors, which seem to belong to a macrophage-monocyte lineage. The enhanced cytotoxic activity induced by cyclophosphamide was not restricted to C. albicans but was also exerted against a panel of Candida strains. PMID:6352489

  16. Suppression of NK cell-mediated cytotoxicity against PRRSV-infected porcine alveolar macrophages in vitro.

    PubMed

    Cao, Jun; Grauwet, Korneel; Vermeulen, Ben; Devriendt, Bert; Jiang, Ping; Favoreel, Herman; Nauwynck, Hans

    2013-06-28

    The adaptive immunity against PRRSV has already been studied in depth, but only limited data are available on the innate immune responses against this pathogen. In the present study, we analyzed the interaction between porcine natural killer (NK) cells and PRRSV-infected primary porcine alveolar macrophages (PAMs), since NK cells are one of the most important components of innate immunity and PAMs are primary target cells of PRRSV infection. NK cytotoxicity assays were performed using enriched NK cells as effector cells and virus-infected or mock-inoculated PAMs as target cells. The NK cytotoxicity against PRRSV-infected PAMs was decreased starting from 6h post inoculation (hpi) till the end of the experiment (12 hpi) and was significantly lower than that against pseudorabies virus (PrV)-infected PAMs. UV-inactivated PRRSV also suppressed NK activity, but much less than infectious PRRSV. Furthermore, co-incubation with PRRSV-infected PAMs inhibited degranulation of NK cells. Finally, using the supernatant of PRRSV-infected PAMs collected at 12 hpi showed that the suppressive effect of PRRSV on NK cytotoxicity was not mediated by soluble factors. In conclusion, PRRSV-infected PAMs showed a reduced susceptibility toward NK cytotoxicity, which may represent one of the multiple evasion strategies of PRRSV. PMID:23522639

  17. MANGANESE CHLORIDE ENHANCES MURINE CELL-MEDIATED CYTOTOXICITY: EFFECTS ON NATURAL KILLER CELLS

    EPA Science Inventory

    Natural killer (NK) cell activity of mice given a single injection of manganese chloride (MnCl2) was significantly enhanced as measured in a 4-hr in vitro 51Cr release assay. Enhanced activity persisted for several days after injection. This cytotoxic activity was associated with...

  18. Fasting-Mimicking Diet Reduces HO-1 to Promote T Cell-Mediated Tumor Cytotoxicity.

    PubMed

    Di Biase, Stefano; Lee, Changhan; Brandhorst, Sebastian; Manes, Brianna; Buono, Roberta; Cheng, Chia-Wei; Cacciottolo, Mafalda; Martin-Montalvo, Alejandro; de Cabo, Rafael; Wei, Min; Morgan, Todd E; Longo, Valter D

    2016-07-11

    Immune-based interventions are promising strategies to achieve long-term cancer-free survival. Fasting was previously shown to differentially sensitize tumors to chemotherapy while protecting normal cells, including hematopoietic stem and immune cells, from its toxic side effects. Here, we show that the combination of chemotherapy and a fasting-mimicking diet (FMD) increases the levels of bone marrow common lymphoid progenitor cells and cytotoxic CD8(+) tumor-infiltrating lymphocytes (TILs), leading to a major delay in breast cancer and melanoma progression. In breast tumors, this effect is partially mediated by the downregulation of the stress-responsive enzyme heme oxygenase-1 (HO-1). These data indicate that FMD cycles combined with chemotherapy can enhance T cell-dependent targeted killing of cancer cells both by stimulating the hematopoietic system and by enhancing CD8(+)-dependent tumor cytotoxicity. PMID:27411588

  19. Epirubicin pretreatment enhances NK cell-mediated cytotoxicity against breast cancer cells in vitro

    PubMed Central

    Feng, Hui; Dong, Ying; Wu, Jing; Qiao, Yuan; Zhu, Ge; Jin, Haofan; Cui, Jiuwei; Li, Wei; Liu, Yong-Jun; Chen, Jingtao; Song, Yanqiu

    2016-01-01

    Anthracycline-based chemotherapy is a conventional treatment for breast cancer. However, it can negatively affect host immune function and thereby impair patients’ quality of life. Boosting the host immune system and reducing the adverse effect of chemotherapy are important for effective cancer treatment. Natural killer (NK) cells stimulate immune responses against cancer; autologous immune enhancement therapy with NK cells prolongs patient survival without significant adverse effects. This study investigated the effects of combined treatment with the anthracycline agent epirubicin (EPI) and NK cells on human breast cancer cells. NK cells were obtained by autologous adoptive cell transfer from breast cancer patients and amplified for 14 days in vitro. The cytotoxicity of NK cells against breast cancer cells was higher following EPI (5.0 μg/ml) pretreatment than without EPI pretreatment or application of EPI alone. The expression of NKG2D ligands [unique long 16-binding protein (ULBP) 1, ULBP2, and major histocompatibility complex class I-related chain A] in breast cancer cells was upregulated by pretreatment with EPI, which also increased the secretion of interferon-γ and tumor necrosis factor-α and expression of perforin and granzyme B in NK cells. These results indicate that EPI-NK cell treatment has synergistic cytotoxic effects against breast cancer cells, and suggest that anthracycline-based chemotherapy and NK cell-based immunotherapy can be combined for more effective breast cancer treatment. PMID:27158340

  20. Effect of carrageenan on the induction of cell-mediated cytotoxic responses in vivo.

    PubMed Central

    Sakemi, T; Kuroiwa, A; Nomoto, K

    1980-01-01

    Carrageenan (CAR), a sulphated polygalactose having macrophage toxic properties, elicited a suppression of primary cytotoxic T lymphocyte (CTL) responses against allogeneic tumour cells in the spleen when the tumour cells (EL-4 tumour cells, H-2b) were administered subcutaneously to AKR mice. When the allogeneic tumour cells were administered intravenously to AKR mice, no CTL responses to the alloantigens were detected in the spleen, but were detected in the peritoneal exudate cells, and CAR treatment suppressed the responses. On the other hand, in vitro secondary CTL responses of cells from alloantigen-primed mice were markedly enhanced by the pre-treatment of such mice with CAR. These results may suggest that two steps, macrophage-dependent and independent, are involved in the development of CTL responses in vivo. PMID:6969217

  1. Role of antibody dependent cell mediated cytotoxicity (ADCC) in Sm-p80-mediated protection against Schistosoma mansoni

    PubMed Central

    Torben, Workineh; Ahmad, Gul; Zhang, Weidong; Nash, Stewart; Le, Loc; Karmakar, Souvik; Siddiqui, Afzal A.

    2012-01-01

    Schistosomiasis is a major health problem in the developing world and for international travelers to the endemic countries. Existing strategies to control schistosomiasis have had limited successes so far. The addition of an effective vaccine in existing control measures would be greatly beneficial in reducing the impact of the disease. In this regard, Sm-p80 mediated protection against intestinal schistosomiasis caused by Schistosoma mansoni has been observed to be promising in two animal models of infection and disease. In this study, the role of antibody dependent cell mediated cytotoxcity (ADCC) was deciphered in Sm-p80-mediated protection especially in the elimination of lung stage schistosomula. This was achieved using lung lavage cells and lung cells that were isolated from mice immunized with and without Sm-p80 formulated in a recombinant vaccine formulation. Significant differences were observed in cytotoxicity assays using immune sera with the lung lavage cells which showed 51% more killing of schistosomula and elevated levels of nitric oxide in the supernatants were detected compared to controls. PMID:23000221

  2. Envelope Glycoprotein Internalization Protects Human and Simian Immunodeficiency Virus-Infected Cells from Antibody-Dependent Cell-Mediated Cytotoxicity

    PubMed Central

    von Bredow, Benjamin; Arias, Juan F.; Heyer, Lisa N.; Gardner, Matthew R.; Farzan, Michael; Rakasz, Eva G.

    2015-01-01

    ABSTRACT The cytoplasmic tails of human and simian immunodeficiency virus (HIV and SIV, respectively) envelope glycoproteins contain a highly conserved, membrane-proximal endocytosis motif that prevents the accumulation of Env on the surface of infected cells prior to virus assembly. Using an assay designed to measure the killing of virus-infected cells by antibody-dependent cell-mediated cytotoxicity (ADCC), we show that substitutions in this motif increase the susceptibility of HIV-1- and SIV-infected cells to ADCC in a manner that directly correlates with elevated Env levels on the surface of virus-infected cells. In the case of HIV-1, this effect is additive with a deletion in vpu recently shown to enhance the susceptibility of HIV-1-infected cells to ADCC as a result of tetherin-mediated retention of budding virions on the cell surface. These results reveal a previously unappreciated role for the membrane-proximal endocytosis motif of gp41 in protecting HIV-1- and SIV-infected cells from antibody responses by regulating the amount of Env present on the cell surface. IMPORTANCE This study reveals an unappreciated role for the membrane-proximal endocytosis motif of gp41 in protecting HIV-1- and SIV-infected cells from elimination by Env-specific antibodies. Thus, strategies designed to interfere with this mechanism of Env internalization may improve the efficacy of antibody-based vaccines and antiretroviral therapies designed to enhance the immunological control of HIV-1 replication in chronically infected individuals. PMID:26269175

  3. Antibody-dependent cell-mediated cytotoxicity against IBR-infected bovine kidney cells by ruminant neutrophils: the role of lysosomal cationic protein.

    PubMed Central

    Thorne, K J; Norman, J M; Haydock, S F; Lammas, D A; Duffus, P H

    1984-01-01

    Antibody-dependent cell-mediated cytotoxicity (ADCC) of infectious bovine rhinotracheitis (IBR)-infected bovine kidney cells (MDBK) by neutrophils was demonstrated. Neutrophils from bovine and sheep mammary exudate and peripheral blood, and also from human peripheral blood, were all active in the presence of anti-IBR antibody. The component of the ruminant neutrophil granules which was responsible for cytotoxicity appeared to be cationic protein since purified cationic protein lysed the virus-infected cells and heparin inhibited cytotoxicity. Human neutrophil cytotoxicity to herpes simplex virus (HSV)-infected human Chang liver cells was also inhibited by heparin. Human neutrophil cytotoxicity to IBR-infected bovine kidney cells did not appear to be mediated by cationic protein since it was inhibited by the chelators of oxidative intermediates DMSO, thiourea, tryptophane, benzoate and mannitol, and not by heparin. PMID:6092270

  4. Separation of effector cells mediating antibody-dependent cellular cytotoxicity (ADC) to erythrocyte targets from those mediating ADC to tumor targets.

    PubMed

    Pollack, S B; Nelson, K; Grausz, J D

    1976-04-01

    Murine spleen cells mediate antibody-dependent cellular cytotoxicity (ADC) both to erythrocyte targets in a 51Cr release assay and to syngeneic tumor targets in a microcytotoxicity assay. The effector cells active in the two ADC assays can be separated by passage of the spleen cells through columns of Sephadex G-10 at 37 degrees C. Cells mediating ADC to sarcoma cells did not adhere to the G-10 and were recovered in the column effluent. These nonadherent cells were not cytotoxic to antibody-coated chicken red blood cells. Spleen cells which mediated ADC in a 51Cr release assay to the red cell targets adhered to G-10. Adherent effector cells could subsequently be recovered from the columns by elution with 5 X 10(-4) M EDTA. PMID:815438

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

    PubMed

    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. PMID:25970007

  6. Propanil Exposure Induces Delayed but Sustained Abrogation of Cell-Mediated Immunity through Direct Interference with Cytotoxic T-Lymphocyte Effectors

    PubMed Central

    Sheil, James M.; Frankenberry, Marc A.; Schell, Todd D.; Brundage, Kathleen M.; Barnett, John B.

    2006-01-01

    The postemergent herbicide propanil (PRN; also known as 3,4-dichloropropionanilide) is used on rice and wheat crops and has well-known immunotoxic effects on various compartments of the immune system, including T-helper lymphocytes, B lymphocytes, and macrophages. It is unclear, however, whether PRN also adversely affects cytotoxic T lymphocytes (CTLs), the primary (1°) effectors of cell-mediated immunity. In this study we examined both the direct and indirect effects of PRN exposure on CTL activation and effector cell function to gauge its likely impact on cell-mediated immunity. Initial experiments addressed whether PRN alters the class I major histocompatibility complex (MHC) pathway for antigen processing and presentation by antigen-presenting cells (APCs), thereby indirectly affecting effector function. These experiments demonstrated that PRN does not impair the activation of CTLs by PRN-treated APCs. Subsequent experiments addressed whether PRN treatment of CTLs directly inhibits their activation and revealed that 1° alloreactive CTLs exposed to PRN are unimpaired in their proliferative response and only marginally inhibited in their lytic activity. Surprisingly, secondary stimulation of these alloreactive CTL effectors, however, even in the absence of further PRN exposure, resulted in complete abrogation of CTL lytic function and a delayed but significant long-term effect on CTL responsiveness. These findings may have important implications for the diagnosis and clinical management of anomalies of cell-mediated immunity resulting from environmental exposure to various herbicides and other pesticides. PMID:16835059

  7. Cell-mediated cytotoxicity of bovine mononuclear cells to IBRV-infected cells: dependence on Sephadex G-10 adherent cells.

    PubMed

    Campos, M; Rossi, C R

    1985-04-01

    Following intranasal inoculation of cattle with infectious bovine rhinotracheitis virus (IBRV) mononuclear cells that produced a genetically unrestricted cytotoxic response against IBRV-infected, but not against uninfected cells, were present in peripheral blood. Cytotoxicity was detected between 6 and 14 days after primary infection in a 20 h, but not in a 5 h, 51Cr-release assay. Cytotoxic activity was present in peripheral blood mononuclear cells from infected and subsequently hyperimmunized cattle for a considerably longer time. Neither natural cytotoxicity, antibody-dependent cell cytotoxicity, nor antibody produced during the assay was responsible for the cytotoxicity. However, cytotoxicity was dependent upon an adherent mononuclear cell that was partially removed by passage over nylon wool and completely removed by passage over Sephadex G-10. PMID:2408374

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

    PubMed

    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. PMID:26138671

  9. C-type lectin-like molecule-1 (CLL1)-targeted TRAIL augments the tumoricidal activity of granulocytes and potentiates therapeutic antibody-dependent cell-mediated cytotoxicity

    PubMed Central

    Wiersma, Valerie R; de Bruyn, Marco; Shi, Ce; Gooden, Marloes JM; Wouters, Maartje CA; Samplonius, Douwe F; Hendriks, Djoke; Nijman, Hans W; Wei, Yunwei; Zhou, Jin; Helfrich, Wijnand; Bremer, Edwin

    2015-01-01

    The therapeutic effect of anti-cancer monoclonal antibodies stems from their capacity to opsonize targeted cancer cells with subsequent phagocytic removal, induction of antibody-dependent cell-mediated cytotoxicity (ADCC) or induction of complement-mediated cytotoxicity (CDC). The major immune effector cells involved in these processes are natural killer (NK) cells and granulocytes. The latter and most prevalent blood cell population contributes to phagocytosis, but is not effective in inducing ADCC. Here, we report that targeted delivery of the tumoricidal protein tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to granulocyte marker C-type lectin-like molecule-1 (CLL1), using fusion protein CLL1:TRAIL, equips granulocytes with high levels of TRAIL. Upon CLL1-selective binding of this fusion protein, granulocytes acquire additional TRAIL-mediated cytotoxic activity that, importantly, potentiates antibody-mediated cytotoxicity of clinically used therapeutic antibodies (e.g., rituximab, cetuximab). Thus, CLL1:TRAIL could be used as an adjuvant to optimize the clinical potential of anticancer antibody therapy by augmenting tumoricidal activity of granulocytes. PMID:25760768

  10. Mechanisms of corticosteroid action on lymphocyte subpopulations. III. Differential effects of dexamethasone administration on subpopulations of effector cells mediating cellular cytotoxicity in man

    PubMed Central

    Parrillo, J. E.; Fauci, A. S.

    1978-01-01

    . Neutrophil ADCC against Ch and HHC was minimal and was not affected by DEX administration. This study demonstrates differential effects of corticosteroids on antibody-dependent cell-mediated cytotoxicity, reflecting changes in proportion of circulating effector cell populations. These changes depend on (a) the target cell employed, (b) the effector cell mediating cytotoxicity and (c) the duration of time since the last dose of corticosteroid. PMID:639343

  11. Evaluation of antigen specific recognition and cell mediated cytotoxicity by a modified lysispot assay in a rat colon carcinoma model

    PubMed Central

    2012-01-01

    Background Antigen-specific CD8+ cytotoxic T lymphocytes represent potent effector cells of the adaptive immune response against viruses as well as tumours. Therefore assays capable at exploring the generation and function of cytotoxic T lymphocytes represent an important objective for both clinical and experimental settings. Methods Here we show a simple and reproducible assay for the evaluation of antigen-specific CD8+ cytotoxic T lymphocytes based on a LysiSpot technique for the simultaneous determination of antigen-specific IFN-γ production and assessment of tumor cytolysis. The assay was developed within an experimental model of colorectal carcinoma, induced by the colorectal tumor cell line DHD-K12 that induces tumors in BDIX rats and, in turn, elicits a tumor- specific immune response. Results Using DHD-K12 cells transfected to express Escherichia coli β-galactosidase as target cells, and by the fine setting of spot colours detection, we have developed an in vitro assay that allows the recognition of cytotoxic T lymphocytes induced in BDIX rats as well as the assessment of anti-tumour cytotoxicity. The method highlighted that in the present experimental model the tumour antigen-specific immune response was bound to killing target cells in the proportion of 55%, while 45% of activated cells were not cytotoxic but released IFN-γ. Moreover in this model by an ELISPOT assay we demonstrated the specific recognition of a nonapeptide epitope called CSH-275 constitutionally express in DHD-K12 cells. Conclusions The assay proved to be highly sensitive and specific, detecting even low frequencies of cytotoxic/activated cells and providing the evaluation of cytokine-expressing T cells as well as the extent of cytotoxicity against the target cells as independent functions. This assay may represent an important tool to be adopted in experimental settings including the development of vaccines or immune therapeutic strategies PMID:22296726

  12. Contrasting Effects of the Cytotoxic Anticancer Drug Gemcitabine and the EGFR Tyrosine Kinase Inhibitor Gefitinib on NK Cell-Mediated Cytotoxicity via Regulation of NKG2D Ligand in Non-Small-Cell Lung Cancer Cells

    PubMed Central

    Okita, Riki; Wolf, Diana; Yasuda, Koichiro; Maeda, Ai; Yukawa, Takuro; Saisho, Shinsuke; Shimizu, Katsuhiko; Yamaguchi, Yoshiyuki; Oka, Mikio; Nakayama, Eiichi; Lundqvist, Andreas; Kiessling, Rolf; Seliger, Barbara; Nakata, Masao

    2015-01-01

    Introduction Several cytotoxic anticancer drugs inhibit DNA replication and/or mitosis, while EGFR tyrosine kinase inhibitors inactivate EGFR signalling in cancer cell. Both types of anticancer drugs improve the overall survival of the patients with non-small-cell lung cancer (NSCLC), although tumors often become refractory to this treatment. Despite several mechanisms by which the tumors become resistant having been described the effect of these compounds on anti-tumor immunity remains largely unknown. Methods This study examines the effect of the cytotoxic drug Gemcitabine and the EGFR tyrosine kinase inhibitor Gefitinib on the expression of NK group 2 member D (NKG2D) ligands as well as the sensitivity of NSCLC cells to the NK-mediated lysis. Results We demonstrate that Gemcitabine treatment leads to an enhanced expression, while Gefitinib downregulated the expression of molecules that act as key ligands for the activating receptor NKG2D and promote NK cell-mediated recognition and cytolysis. Gemcitabine activated ATM and ATM- and Rad-3-related protein kinase (ATR) pathways. The Gemcitabine-induced phosphorylation of ATM as well as the upregulation of the NKG2D ligand expression could be blocked by an ATM-ATR inhibitor. In contrast, Gefitinib attenuated NKG2D ligand expression. Silencing EGFR using siRNA or addition of the PI3K inhibitor resulted in downregulation of NKG2D ligands. The observations suggest that the EGFR/PI3K pathway also regulates the expression of NKG2D ligands. Additionally, we showed that both ATM-ATR and EGFR regulate MICA/B via miR20a. Conclusion In keeping with the effect on NKG2D expression, Gemcitabine enhanced NK cell-mediated cytotoxicity while Gefitinib attenuated NK cell killing in NSCLC cells. PMID:26439264

  13. Comparing high-throughput methods to measure NK cell-mediated antibody dependent cellular cytotoxicity during HIV-infection.

    PubMed

    Konstantinus, Iyaloo N; Gamieldien, Hoyam; Mkhize, Nonhlanhla N; Kriek, Jean-Mari; Passmore, Jo-Ann S

    2016-07-01

    HIV-specific binding antibody responses, including those mediating antibody-dependent cellular cytotoxicity (ADCC), provided the best functional correlate of lower risk of infection in the RV144 HIV-1 vaccine clinical trial. The aim of this study was to compare two high-throughput flow cytometry based methods to measure HIV-specific ADCC responses, the GranToxilux and PanToxilux assays. Plasma from nine HIV-1 seropositive individuals was screened for binding antibody titres against HIV-1 subtype C gp120 by ELISA and western blot. Plasma from six HIV-negative individuals was included as controls. Both ADCC assays used subtype C gp120-coated CEM.NKRCCR5 cells as targets. The PanToxilux assay (which measured both granzyme B and caspase activity) measured higher levels of direct natural killer (NK) cell killing of K562 tumour cells than the GranToxilux assay (granzyme B alone; p<0.05). In ADCC assays in which NK cell killing was directed against gp120-coated CEM.NKRCCR5 cells in an antibody-dependent manner, plasma from HIV-positive individuals yielded significantly higher levels of ADCC activity than the HIV-negative controls. In contrast to direct killing, the GranToxilux assay measured similar levels of ADCC killing as the PanToxilux assay but had significantly lower background cytotoxicity against target cells coated with HIV negative serum. In conclusion, the PanToxilux assay was more sensitive for detecting direct NK cell killing of K562 cells than the GranToxilux assay, although the GranToxilux assay performed better at detecting HIV-specific ADCC activity, because of lower background cytotoxicity from HIV-negative serum. This is the first study to compare GranToxilux and PanToxilux ability to detect ADCC during HIV infection. PMID:27094485

  14. Development of IgG Mediated Antibody Dependent Cell-mediated Cytotoxicity (ADCC) in the Serum and Genital Mucosa of HIV Seroconverters

    PubMed Central

    Aziz, Mariam; Mahmood, Fareeha; Mata, Mariana; Durkin, Helen G; Liu, Chenglong; Greenblatt, Ruth M; Nowicki, Marek; Golub, Elizabeth T; Anastos, Kathryn; French, Audrey L; Baum, Linda L

    2015-01-01

    Background We measured antibody-dependent cell mediated cytotoxicity (ADCC) activity in serum and genital fluids of heterosexually exposed women during HIV seroconversion. Methods Plasma and cervico-vaginal lavage (CVL) fluid from 11 seroconverters (SC) were analyzed biannually from one year pre- to 6 year post-seroconversion using a 51Cr-release assay to measure HIV-1 gp120 specific ADCC. Results No SC had significant HIV specific CVL ADCC activity before seroconversion or until 1.5 yr after seroconversion. One individual had a %Specific Release (SR) of 25.4 at 2 years, 26.7 at 3 years and 21.0 at 4 years after seroconversion in CVL. Another sample had 4.7% SR at 2 years, 5.3 at 3 years, 10.9 at 4 years, and 8.4 at 5 years after seroconversion in CVL. A third had no activity until 17% SR 5 years after seroconversion in CVL. A fourth showed activity of 36.5% SR at 6.5 years after seroconversion. Seven women had no ADCC activity in their CVL. Paired serum samples showed HIV specific ADCC activity prior to the appearance of CVL ADCC activity. Conclusions HIV specific ADCC activity in CVL rose 2 years after seroconversion; ADCC was present in the serum prior to this time. These data suggest that genital tract ADCC activity is not present until well after acute infection. PMID:26798561

  15. Small CD4 Mimetics Prevent HIV-1 Uninfected Bystander CD4 + T Cell Killing Mediated by Antibody-dependent Cell-mediated Cytotoxicity

    PubMed Central

    Richard, Jonathan; Veillette, Maxime; Ding, Shilei; Zoubchenok, Daria; Alsahafi, Nirmin; Coutu, Mathieu; Brassard, Nathalie; Park, Jongwoo; Courter, Joel R.; Melillo, Bruno; Smith, Amos B.; Shaw, George M.; Hahn, Beatrice H.; Sodroski, Joseph; Kaufmann, Daniel E.; Finzi, Andrés

    2015-01-01

    Human immunodeficiency virus type 1 (HIV-1) infection causes a progressive depletion of CD4 + T cells. Despite its importance for HIV-1 pathogenesis, the precise mechanisms underlying CD4 + T-cell depletion remain incompletely understood. Here we make the surprising observation that antibody-dependent cell-mediated cytotoxicity (ADCC) mediates the death of uninfected bystander CD4 + T cells in cultures of HIV-1-infected cells. While HIV-1-infected cells are protected from ADCC by the action of the viral Vpu and Nef proteins, uninfected bystander CD4 + T cells bind gp120 shed from productively infected cells and are efficiently recognized by ADCC-mediating antibodies. Thus, gp120 shedding represents a viral mechanism to divert ADCC responses towards uninfected bystander CD4 + T cells. Importantly, CD4-mimetic molecules redirect ADCC responses from uninfected bystander cells to HIV-1-infected cells; therefore, CD4-mimetic compounds might have therapeutic utility in new strategies aimed at specifically eliminating HIV-1-infected cells. PMID:26870823

  16. Overcoming chemoresistance of small-cell lung cancer through stepwise HER2-targeted antibody-dependent cell-mediated cytotoxicity and VEGF-targeted antiangiogenesis

    PubMed Central

    Minami, Toshiyuki; Kijima, Takashi; Kohmo, Satoshi; Arase, Hisashi; Otani, Yasushi; Nagatomo, Izumi; Takahashi, Ryo; Miyake, Kotaro; Higashiguchi, Masayoshi; Morimura, Osamu; Ihara, Shoichi; Tsujino, Kazuyuki; Hirata, Haruhiko; Inoue, Koji; Takeda, Yoshito; Kida, Hiroshi; Tachibana, Isao; Kumanogoh, Atsushi

    2013-01-01

    Small-cell lung cancer (SCLC) easily recurs with a multidrug resistant phenotype. However, standard therapeutic strategies for relapsed SCLC remain unestablished. We found that human epidermal growth factor receptor 2 (HER2) is not only expressed in pretreated human SCLC specimens, but is also upregulated when HER2-positive SCLC cells acquire chemoresistance. Trastuzumab induced differential levels of antibody-dependent cell-mediated cytotoxicity (ADCC) to HER2-positive SCLC cells. Furthermore, as a mechanism of the differential levels of ADCC, we have revealed that coexpression of intracellular adhesion molecule (ICAM)-1 on SCLC cells is essential to facilitate and accelerate the trastuzumab-mediated ADCC. Although SN-38–resistant SCLC cells lacking ICAM-1 expression were still refractory to trastuzumab, their in vivo growth was significantly suppressed by bevacizumab treatment due to dependence on their distinctive and abundant production of vascular endothelial growth factor. Collectively, stepwise treatment with trastuzumab and bevacizumab is promising for the treatment of chemoresistant SCLC. PMID:24036898

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

    PubMed Central

    2013-01-01

    Background 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. Methods 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). Results 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. Conclusion 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

  18. The strong in vivo anti-tumor effect of the UIC2 monoclonal antibody is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity.

    PubMed

    Szalóki, Gábor; Krasznai, Zoárd T; Tóth, Ágnes; Vízkeleti, Laura; Szöllősi, Attila G; Trencsényi, György; Lajtos, Imre; Juhász, István; Krasznai, Zoltán; Márián, Teréz; Balázs, Margit; Szabó, Gábor; Goda, Katalin

    2014-01-01

    P-glycoprotein (Pgp) extrudes a large variety of chemotherapeutic drugs from the cells, causing multidrug resistance (MDR). The UIC2 monoclonal antibody recognizes human Pgp and inhibits its drug transport activity. However, this inhibition is partial, since UIC2 binds only to 10-40% of cell surface Pgps, while the rest becomes accessible to this antibody only in the presence of certain substrates or modulators (e.g. cyclosporine A (CsA)). The combined addition of UIC2 and 10 times lower concentrations of CsA than what is necessary for Pgp inhibition when the modulator is applied alone, decreased the EC50 of doxorubicin (DOX) in KB-V1 (Pgp+) cells in vitro almost to the level of KB-3-1 (Pgp-) cells. At the same time, UIC2 alone did not affect the EC50 value of DOX significantly. In xenotransplanted severe combined immunodeficient (SCID) mice co-treated with DOX, UIC2 and CsA, the average weight of Pgp+ tumors was only ∼10% of the untreated control and in 52% of these animals we could not detect tumors at all, while DOX treatment alone did not decrease the weight of Pgp+ tumors. These data were confirmed by visualizing the tumors in vivo by positron emission tomography (PET) based on their increased 18FDG accumulation. Unexpectedly, UIC2+DOX treatment also decreased the size of tumors compared to the DOX only treated animals, as opposed to the results of our in vitro cytotoxicity assays, suggesting that immunological factors are also involved in the antitumor effect of in vivo UIC2 treatment. Since UIC2 binding itself did not affect the viability of Pgp expressing cells, but it triggered in vitro cell killing by peripheral blood mononuclear cells (PBMCs), it is concluded that the impressive in vivo anti-tumor effect of the DOX-UIC2-CsA treatment is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity (ADCC). PMID:25238617

  19. Proteomic comparison of 3D and 2D glioma models reveals increased HLA-E expression in 3D models is associated with resistance to NK cell-mediated cytotoxicity.

    PubMed

    He, Weiqi; Kuang, Yongqin; Xing, Xuemin; Simpson, Richard J; Huang, Haidong; Yang, Tao; Chen, Jingmin; Yang, Libin; Liu, Enyu; He, Weifeng; Gu, Jianwen

    2014-05-01

    Three-dimensional cell culture techniques can better reflect the in vivo characteristics of tumor cells compared with traditional monolayer cultures. Compared with their 2D counterparts, 3D-cultured tumor cells showed enhanced resistance to the cytotoxic T cell-mediated immune response. However, it remains unclear whether 3D-cultured tumor cells have an enhanced resistance to NK cell cytotoxicity. In this study, a total of 363 differentially expressed proteins were identified between the 2D- and 3D-cultured U251 cells by comparative proteomics, and an immune-associated protein-protein interaction (PPI) network based on these differential proteins was constructed by bioinformatics. Within the network, HLA-E, as a molecule for inhibiting NK cell activation, was significantly up-regulated in the 3D-cultured tumor cells. Then, we found that the 3D-cultured U251 cells exhibited potent resistance to NK cell cytotoxicity in vitro and were prone to tumor formation in vivo. The resistance of the 3D-cultured tumor cells to NK cell lysis was mediated by the HLA-E/NKG2A interaction because the administration of antibodies that block either HLA-E or NKG2A completely eliminated this resistance and significantly decreased tumor formation. Taken together, our findings indicate that HLA-E up-regulation in 3D-cultured cells may result in enhanced tumor resistance to NK cell-mediated immune response. PMID:24742303

  20. Cytotoxic activity against human neuroblastoma and melanoma cells mediated by IgM antibodies derived from peripheral blood of healthy donors.

    PubMed

    Devarapu, Satish Kumar; Mamidi, Srinivas; Plöger, Frank; Dill, Othmar; Blixt, Ola; Kirschfink, Michael; Schwartz-Albiez, Reinhard

    2016-06-15

    A small percentage of healthy donors identified in the Western population carry antibodies in their peripheral blood which convey cytotoxic activity against certain human melanoma and neuroblastoma cell lines. We measured the cytotoxic activity of sera and plasmas from healthy donors on the human neuroblastoma cell line Kelly and various melanoma cell lines. Antibodies of IgM isotype, presumably belonging to the class of naturally occurring antibodies, exerted cytotoxic activity in a complement-dependent fashion. Apart from complement-dependent tumor cell lysis, we observed C3 opsonization in all tumor cell lines upon treatment with cytotoxic plasmas. Cell lines tested primarily expressed membrane complement regulatory proteins (mCRP) CD46, CD55 and CD59 to various extents. Blocking of mCRPs by monoclonal antibodies enhanced cell lysis and opsonization, though some melanoma cells remained resistant to complement attack. Epitopes recognized by cytotoxic antibodies were represented by gangliosides such as GD2 and GD3, as evidenced by cellular sialidase pretreatment and enhanced expression of distinct gangliosides. It remains to be clarified why only a small fraction of healthy persons carry these antitumor cytotoxic antibodies. PMID:26830059

  1. HLA-G1-transfected K562 cells do not inhibit NK-cell-mediated lysis in europium release cytotoxicity assay.

    PubMed

    Sapak, M; Buc, M

    2003-01-01

    The class Ia of HLA molecules are recognised by NK-cells either by inhibitory or stimulatory NK-receptors. When inhibitory signals prevail over stimulatoryones, the target cells expressing the class Ia of HLA molecules are not lysed by NK-cells. Similarly, class Ib of HLA molecules have been reported to induce the inhibitory signal in NK-cells. The cell line K562 is deprived of both class Ia and class Ib of HLA molecules, respectively, the fact of which enhances the lysis of K562 cells when they are co-cultivated with NK-cells. To study the role of HLA-G molecules in NK-cell cytotoxic activity, HLA-G tranfected K562 cells were used as target cells. NK-cells were isolated from the peripheral blood of 4 unrelated persons using Miltenyi's Biotec isolation system. The purity of directly isolated NK cells (CD56 Multisort kit) was 74.1%, and that of indirectly isolated NK-cells (NK-cell isolation kit) 69.4%. The europium release cytotoxicity assay was used in all experiments. The percentage of cytotoxicity ranged from 19% to 24% when K562 target cells were used. Similar results were obtained with the HLA-G1-transfected target cells: the percentage of cytotoxicity ranged from 17% to 29%. Our preliminary results indicate that NK-cells are able to lyse both, K562 cells and the HLA-G1-transfected K562 cells. (Tab. 1, Fig. 8, Ref. 21.). PMID:15055728

  2. A novel method for evaluating antibody-dependent cell-mediated cytotoxicity by flowcytometry using cryopreserved human peripheral blood mononuclear cells

    PubMed Central

    Yamashita, Makiko; Kitano, Shigehisa; Aikawa, Hiroaki; Kuchiba, Aya; Hayashi, Mitsuhiro; Yamamoto, Noboru; Tamura, Kenji; Hamada, Akinobu

    2016-01-01

    Analyzing the cytotoxic functions of effector cells, such as NK cells against target cancer cells, is thought to be necessary for predicting the clinical efficacy of antibody-dependent cellular cytotoxicity (ADCC) -dependent antibody therapy. The 51Cr release assay has long been the most widely used method for quantification of ADCC activity. However, the reproducibilities of these release assays are not adequate, and they do not allow evaluation of the lysis susceptibilities of distinct cell types within the target cell population. In this study, we established a novel method for evaluating cytotoxicity, which involves the detection and quantification of dead target cells using flowcytometry. CFSE (carboxyfluorescein succinimidyl ester) was used as a dye to specifically stain and thereby label the target cell population, allowing living and dead cells, as well as both target and effector cells, to be quantitatively distinguished. Furthermore, with our new approach, ADCC activity was more reproducibly, sensitively, and specifically detectable, not only in freshly isolated but also in frozen human peripheral blood mononuclear cells (PBMCs), than with the calcein-AM release assay. This assay, validated herein, is expected to become a standard assay for evaluating ADCC activity which will ultimately contribute the clinical development of ADCC dependent-antibody therapies. PMID:26813960

  3. In vitro analysis of T cell-mediated cytotoxicity displayed by rat heart allograft recipients rendered unresponsive by total-lymphoid irradiation and extracted donor antigen

    SciTech Connect

    Florence, L.S.; Jiang, G.L.; Ang, K.K.; Stepkowski, S.M.; Kahan, B.D. )

    1990-02-01

    The addition of 3M KCl-extracted donor antigen (HAg) to immunosuppressive therapy with 16 Gy total lymphoid irradiation produces a significantly higher fraction of Wistar-Furth (WFu) recipients displaying indefinite survival of heterotopic buffalo (BUF) heart allografts, namely 80 versus 20%. The experiments presented herein analyzed the direct activity as well as estimated the potential precursor numbers at 1 and 3 months in treated recipients. At 1 month post-TLI/HAg therapy, recipients showed reduced proliferative responses in mixed lymphocyte reactions (MLR) in a specific pattern toward donor but not third-party stimulators. Both TLI/Graft and TLI/HAg/Graft groups showed a higher frequency of BUF antigen-directed T-cytotoxic cells (fTc) than TLI-treated, but nontransplanted, WFu hosts. In addition, the TLI/HAg group alone displayed alloantigen-specific suppressor cells that suppressed the MLR proliferative responses of normal spleen T cells against donor, but not third-party, alloantigens. At 3 months postirradition, both TLI/Graft and TLI/HAg/Graft groups displayed variable MLR proliferative responses toward donor and third-party alloantigens. Whereas nontransplanted, TLI-treated WFu rats recovered their fTc to normal levels at 3 months, the TLI and TLI/HAg treated recipients bearing functional heart allografts demonstrated significantly decreased splenic fTc. These results show that reduced numbers of cytotoxic cell precursors may afford more reliable indices of prolonged heart allograft survival than MLR responses. The observations suggest that TLI/HAg transplant hosts display both reduced cytotoxic precursors and activated suppressor elements.

  4. Advantage of tacrolimus/mycophenolate mofetil regimen for cytotoxic T cell-mediated defence and its inhibition by additive steroid administration in high-risk liver transplant recipients.

    PubMed

    Uemoto, S; Ozawa, K; Kaido, T; Mori, A; Fujimoto, Y

    2016-04-01

    Our previous work revealed that the recipients with the highest pre-existing numbers of CD8(+) effector T cells (TE ) [hyperparathyroidism (HPT)E recipients] occupied approximately 30% of adult transplant recipients performed in our hospital. HPTE recipients demonstrated very poor clinical outcome compared with the remaining 70% of recipients with the lowest pre-existing TE (LPTE recipient). This study aimed to clarify the best combined immunosuppressive regimen related to function of cytotoxic T lymphocytes (CTLs) for HPTE recipients. Eighty-one HPTE recipients were classified into three types, according to the immunosuppressive regimens: type 1, tacrolimus (Tac)/glucocorticoid (GC); type 2, Tac/mycophenolate mofetil (MMF)/GC; and type 3, Tac/MMF. Frequencies of severe infection, rejection and hospital death were the highest in types 1 and 2, whereas the lowest occurred in type 3. The survival rate in type 3 was the highest (100%) during follow-up until post-operative day 2000. Regarding the immunological mechanism, in type 1 TE perforin and interferon (IFN)-γ were generated through the self-renewal of CD8(+) central memory T cells (TCM ), but decreased in the early post-transplant period due to marked down-regulation of interleukin (IL)-12 receptor beta-1 of TCM. In type 2, the self-renewal TCM did not develop, and the effector function could not be increased. In type 3, in contrast, the effectors and cytotoxicity were correlated inversely with IL-12Rβ1(+) TCM levels, and increased at the highest level around the pre-transplant levels of IL-12Rβ1(+) TCM . However, the immunological advantage of Tac/MMF therapy was inhibited strongly by additive steroid administration. PMID:26560892

  5. T cell-mediated hepatitis in mice infected with lymphocytic choriomeningitis virus. Liver cell destruction by H-2 class I-restricted virus-specific cytotoxic T cells as a physiological correlate of the /sup 51/Cr-release assay

    SciTech Connect

    Zinkernagel, R.M.; Haenseler, E.; Leist, T.; Cerny, A.; Hengartner, H.; Althage, A.

    1986-10-01

    A model for immunologically T cell-mediated hepatitis was established in mice infected with lymphocytic choriomeningitis virus (LCMV). The severity of hepatitis was monitored histologically and by determination of changes in serum levels of the enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutamate dehydrogenase (GLDH), and alkaline phosphatase (AP). Kinetics of histological disease manifestations, increases of liver enzyme levels in the serum, and cytotoxic T cell activities in livers and spleens all correlated and were dependent upon several parameters: LCMV-isolate; LCMV-WE caused extensive hepatitis, LCMV-Armstrong virtually none. Virus dose. Route of infection; i.v. or i.p. infection caused hepatitis, whereas infection into the footpad did not. The general genetic background of the murine host; of the strains tested, Swiss mice and A-strain mice were more susceptible than C57BL or CBA mice; BALB/c and DBA/2 mice were least susceptible. The degree of immunocompetence of the murine host; T cell deficient nu/nu mice never developed hepatitis, whereas nu/+ or +/+ mice always did. B cell-depleted anti-IgM-treated mice developed immune-mediated hepatitis comparably or even more extensively than control mice. Local cytotoxic T cell activity; mononuclear cells isolated from livers during the period of overt hepatitis were two to five times more active than equal numbers of spleen cells. Adoptive transfer of nylon wool-nonadherent anti-Thy-1.2 and anti-Lyt-2 plus C-sensitive, anti-L3T4 plus C-resistant lymphocytes into irradiated mice preinfected with LCMV-WE caused a rapid time- and dose-dependent linear increase of serum enzyme levels. This increase was caused by adoptive transfer of lymphocytes if immune cell donors and recipient mice shared class I, but not when they shared class II histocompatibility antigens.

  6. A Human Anti-M2 Antibody Mediates Antibody-Dependent Cell-Mediated Cytotoxicity (ADCC) and Cytokine Secretion by Resting and Cytokine-Preactivated Natural Killer (NK) Cells

    PubMed Central

    Simhadri, Venkateswara R.; Dimitrova, Milena; Mariano, John L.; Zenarruzabeitia, Olatz; Zhong, Weimin; Ozawa, Tatsuhiko; Muraguchi, Atsushi; Kishi, Hiroyuki; Eichelberger, Maryna C.; Borrego, Francisco

    2015-01-01

    The highly conserved matrix protein 2 (M2) is a good candidate for the development of a broadly protective influenza vaccine that induces long-lasting immunity. In animal models, natural killer (NK) cells have been proposed to play an important role in the protection provided by M2-based vaccines through a mechanism of antibody-dependent cell-mediated cytotoxicity (ADCC). We investigated the ability of the human anti-M2 Ab1-10 monoclonal antibody (mAb) to activate human NK cells. They mediated ADCC against M2-expressing cells in the presence of Ab1-10 mAb. Furthermore, NK cell pro-inflammatory cytokine and chemokine secretion is also enhanced when Ab1-10 mAb is present. We also generated cytokine-preactivated NK cells and showed that they still displayed increased effector functions in the presence of Ab1-10 mAb. Thus, our study has demonstrated that human resting and cytokine-preactivated NK cells may have a very important role in the protection provided by anti-M2 Abs. PMID:25915748

  7. B Cells Are Critical to T-cell-Mediated Antitumor Immunity Induced by a Combined Immune-Stimulatory/Conditionally Cytotoxic Therapy for Glioblastoma12

    PubMed Central

    Candolfi, Marianela; Curtin, James F; Yagiz, Kader; Assi, Hikmat; Wibowo, Mia K; Alzadeh, Gabrielle E; Foulad, David; Muhammad, AKM G; Salehi, Sofia; Keech, Naomi; Puntel, Mariana; Liu, Chunyan; Sanderson, Nicholas R; Kroeger, Kurt M; Dunn, Robert; Martins, Gislaine; Lowenstein, Pedro R; Castro, Maria G

    2011-01-01

    We have demonstrated that modifying the tumor microenvironment through intratumoral administration of adenoviral vectors (Ad) encoding the conditional cytotoxic molecule, i.e., HSV1-TK and the immune-stimulatory cytokine, i.e., fms-like tyrosine kinase 3 ligand (Flt3L) leads to T-cell-dependent tumor regression in rodent models of glioblastoma. We investigated the role of B cells during immune-mediated glioblastoma multiforme regression. Although treatment with Ad-TK+Ad-Flt3L induced tumor regression in 60% of wild-type (WT) mice, it completely failed in B-cell-deficient Igh6-/- mice. Tumor-specific T-cell precursors were detected in Ad-TK+Ad-Flt3L-treated WT mice but not in Igh6-/- mice. The treatment also failed in WT mice depleted of total B cells or marginal zone B cells. Because we could not detect circulating antibodies against tumor cells and the treatment was equally efficient in WT mice and in mice with B-cell-specific deletion of Prdm 1 (encoding Blimp-1), in which B cells are present but unable to fully differentiate into antibody-secreting plasma cells, tumor regression in this model is not dependent on B cells' production of tumor antigen-specific immunoglobulins. Instead, B cells seem to play a role as antigen-presenting cells (APCs). Treatment with Ad-TK+Ad-Flt3L led to an increase in the number of B cells in the cervical lymph nodes, which stimulated the proliferation of syngeneic T cells and induced clonal expansion of antitumor T cells. Our data show that B cells act as APCs, playing a critical role in clonal expansion of tumor antigen-specific T cells and brain tumor regression. PMID:22028620

  8. Removal of a C-terminal serine residue proximal to the inter-chain disulfide bond of a human IgG1 lambda light chain mediates enhanced antibody stability and antibody dependent cell-mediated cytotoxicity

    PubMed Central

    Shen, Yang; Zeng, Lin; Zhu, Aiping; Blanc, Tim; Patel, Dipa; Pennello, Anthony; Bari, Amtul; Ng, Stanley; Persaud, Kris; Kang, Yun (Kenneth); Balderes, Paul; Surguladze, David; Hindi, Sagit; Zhou, Qinwei; Ludwig, Dale L.; Snavely, Marshall

    2013-01-01

    Optimization of biophysical properties is a critical success factor for the developability of monoclonal antibodies with potential therapeutic applications. The inter-domain disulfide bond between light chain (Lc) and heavy chain (Hc) in human IgG1 lends structural support for antibody scaffold stability, optimal antigen binding, and normal Fc function. Recently, human IgG1λ has been suggested to exhibit significantly greater susceptibility to reduction of the inter Lc-Hc disulfide bond relative to the same disulfide bond in human IgG1κ. To understand the molecular basis for this observed difference in stability, the sequence and structure of human IgG1λ and human IgG1κ were compared. Based on this Lc comparison, three single mutations were made in the λ Lc proximal to the cysteine residue, which forms a disulfide bond with the Hc. We determined that deletion of S214 (dS) improved resistance of the association between Lc and Hc to thermal stress. In addition, deletion of this terminal serine from the Lc of IgG1λ provided further benefit, including an increase in stability at elevated pH, increased yield from transient transfection, and improved in vitro antibody dependent cell-mediated cytotoxicity (ADCC). These observations support the conclusion that the presence of the terminal serine of the λ Lc creates a weaker inter-chain disulfide bond between the Lc and Hc, leading to slightly reduced stability and a potential compromise in IgG1λ function. Our data from a human IgG1λ provide a basis for further investigation of the effects of deleting terminal serine from λLc on the stability and function of other human IgG1λ antibodies. PMID:23567210

  9. Removal of terminal alpha-galactosyl residues from xenogeneic porcine endothelial cells. Decrease in complement-mediated cytotoxicity but persistence of IgG1-mediated antibody-dependent cell-mediated cytotoxicity.

    PubMed

    Watier, H; Guillaumin, J M; Piller, F; Lacord, M; Thibault, G; Lebranchu, Y; Monsigny, M; Bardos, P

    1996-07-15

    To determine the role of the terminal alpha-galactosyl residue in the endothelial damage mediated by human xenoreactive natural antibodies (IgM and IgG), we treated porcine endothelial cells in culture with green coffee bean alpha-galactosidase. A practically complete removal of terminal alpha-Gal residues (as evaluated by flow cytometry with Bandeiraea simplicifolia isolectin B4) and concomitant exposure of N-acetyllactosamine were obtained without altering cell viability. A dramatic decrease in IgM and IgG binding (from a pool of human sera) was observed, confirming the key role of the alpha-galactosyl residues. The enzyme treatment did not induce any nonspecific immunoglobulin binding sites, but led to the exposure of new epitopes for a minor fraction of IgM. The main residual IgM and IgG binding could be due to xenoantigens other than the alpha-galactosyl residues. When alpha-galactosidase-treated endothelial cells were used as targets in cytotoxicity experiments, they were less susceptible than untreated cells to complement-mediated cytotoxicity induced by fresh human serum. In contrast, they did not acquire resistance to human IgG-dependent cellular cytotoxicity, despite the decrease in IgG binding. Because it is known that antibody-dependent cytotoxicity mediated by CD16+ NK cells is dependent on IgG1 and IgG3, and not on IgG2 or IgG4, which was confirmed by blocking experiments, we studied the binding of all four subclasses to intact and alpha-galactosidase-treated endothelial cells. Two major subclasses, IgG1 and IgG2, bound to untreated endothelial cells, whereas IgG3 binding was low and IgG4 binding was negligible. A decrease in IgG1, IgG2, and IgG3 binding was observed upon alpha-galactosidase treatment, indicating that antibodies belonging to these three subclasses recognize alpha-galactosyl residues. The decrease in IgG2 binding was more pronounced than the decrease in IgG1 binding. Collectively, these data indicate that IgG1 xenoreactive natural

  10. γδ T Cell-Mediated Antibody-Dependent Cellular Cytotoxicity with CD19 Antibodies Assessed by an Impedance-Based Label-Free Real-Time Cytotoxicity Assay.

    PubMed

    Seidel, Ursula Jördis Eva; Vogt, Fabian; Grosse-Hovest, Ludger; Jung, Gundram; Handgretinger, Rupert; Lang, Peter

    2014-01-01

    γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T cells with CD19 antibodies for immunotherapy of B-lineage ALL, γδ T cells were expanded after a GMP-compliant protocol and ADCC of both primary and expanded γδ T cells with an Fc-optimized CD19 antibody (4G7SDIE) and a bi-specific antibody with the specificities CD19 and CD16 (N19-C16) was evaluated in CD107a-degranulation assays and intracellular cytokine staining. CD107a, TNFα, and IFNγ expression of primary γδ T cells were significantly increased and correlated with CD16-expression of γδ T cells. γδ T cells highly expressed CD107a after expansion and no further increased expression by 4G7SDIE and N19-C16 was measured. Cytotoxicity of purified expanded γδ T cells targeting CD19-expressing cells was assessed in both europium-TDA release and in an impedance-based label-free method (using the xCELLigence system) measuring γδ T cell lysis in real-time. Albeit in the 2 h end-point europium-TDA release assay no increased lysis was observed, in real-time xCELLigence assays both significant antibody-independent cytotoxicity and ADCC of γδ T cells were observed. The xCELLigence system outperformed the end-point europium-TDA release assay in sensitivity and allows drawing of conclusions to lysis kinetics of γδ T cells over prolonged periods of time periods. Combination of CD19 antibodies with primary as well as expanded γδ T cells exhibits a promising approach, which may enhance clinical outcome of patients with pediatric B-lineage ALL and requires clinical

  11. Effect of a recombinant lectin, Viscum album agglutinin on the secretion of interleukin-12 in cultured human peripheral blood mononuclear cells and on NK-cell-mediated cytotoxicity of rat splenocytes in vitro and in vivo.

    PubMed

    Hajto, T; Hostanska, K; Weber, K; Zinke, H; Fischer, J; Mengs, U; Lentzen, H; Saller, R

    1998-01-01

    A plant lectin, Viscum album agglutinin-I (VAA-I) has been shown to increase the number and cytotoxic activity of natural killer (NK) cells in animal models, but the mechanisms underlying these effects are poorly understood. We investigated the effects of the recombinant form of this lectin (rVAA) on secretion of interleukin (IL)-12 and on NK-mediated cytotoxicity against K562 target cells in cultures of human peripheral blood mononuclear cells (PBMC) as well as against YAC-1 target cells in cultured rat spleen cells. In 24-hour cultures of PBMC, 10 ng/ml plant VAA-I and 50 ng/ml rVAA induced significant increases in the secretion of total IL-12. Its biologically active heterodimeric form, p70, was also significantly induced by rVAA. Preincubation of PBMC or splenocytes for 48 h with rVAA in concentrations ranging between 10 pg/ml and 100 pg/ml resulted in moderate enhancements of NK-mediated cytotoxicity. However, coincubation of a low dose of rVAA (100 pg/ml) together with IL-2 and IL-12 (60 U/ml and 2 U/ml, respectively) led to additive stimulation of NK activity. In in vivo experiments, rVAA showed an enhancing effect on NK activity with a bell-shaped curve of efficacy. Forty-eight hours after a single intravenous injection of its most effective doses, 0.5 and 1 ng/kg, into Wistar rats, the NK cytotoxicity of splenocytes against YAC-1 targets doubled, and the frequency of large granular lymphocytes in peripheral blood showed 2.1- and 3-fold increases as compared to control animals. Twenty-four hours following these low lectin doses, the number of large granular lymphocytes was also significantly elevated. After 48 h, 0.5 ng/kg rVAA induced a significant augmentation in the percentage of peripheral Mac-1+ mononuclear cells, including activated monocytes and NK cells. The present results suggest that rVAA augments the secretion of an active form of IL-12 and potentiates the cytokine-induced NK activation. These effects of rVAA may be related to its stimulatory

  12. Cetuximab ± chemotherapy enhances dendritic cell-mediated phagocytosis of colon cancer cells and ignites a highly efficient colon cancer antigen-specific cytotoxic T-cell response in vitro.

    PubMed

    Correale, P; Botta, C; Cusi, M G; Del Vecchio, M T; De Santi, M M; Gori Savellini, G; Bestoso, E; Apollinari, S; Mannucci, S; Marra, M; Abbruzzese, A; Aquino, A; Turriziani, M; Bonmassar, L; Caraglia, M; Tagliaferri, P

    2012-04-01

    Cetuximab is a human/mouse chimeric IgG1 monoclonal antibody (mAb) to epidermal growth factor receptor, approved for colorectal carcinoma treatment in combination with chemotherapy. The immune-mediated effects elicited by its human fraction of crystallization moiety might critically contribute to the overall anti-tumor effectiveness of the antibody. We therefore investigated cetuximab ability to promote colon cancer cell opsonization and phagocytosis by human dendritic cells (DCs) that are subsequently engaged in antigen-cross presentation to cytotoxic T-lymphocyte (CTL) precursors. Human colon cancer cell lines were evaluated for susceptibility to DC-mediated phagocytosis before and after treatment with chemotherapy ± cetuximab in vitro. Human DCs loaded with control or drug-treated cetuximab-coated colon cancer cells were used to in vitro generate cytotoxic T cell clones from peripheral blood mononuclear cells of human leucocyte antigen-A(*)02.01(+) donors. T-cell cultures were characterized for immune-phenotype and tumor-antigen specific CTL activity. The results confirmed that treatment of tumor cells with irinotecan + L-folinate + 5-flurouracil (ILF) or with gemcitabine + ILF increased tumor antigen expression. Moreover, malignant cells exposed to chemotherapy and cetuximab were highly susceptible to phagocytosis by human DCs and were able to promote their activation. The consequent DC-mediated cross-priming of antigens derived from mAb-covered/drug-treated cancer cells elicited a robust CTL anti-tumor response. On the basis of our data, we suggest a possible involvement of CTL-dependent immunity in cetuximab anti-cancer effects. PMID:21618510

  13. Curculigoside augments cell-mediated immune responses in metastatic tumor-bearing animals.

    PubMed

    Murali, Vishnu Priya; Kuttan, Girija

    2016-08-01

    A positive modulation of immune system is necessary for preparing the body to fight against malignant tumor cells. In the present study, the stimulatory effect of Curculigoside on cell-mediated immune response against the metastasis of B16F10 melanoma cells was analyzed in C57BL/6 mice. Curculigoside is a phenolic glucoside present in the plant Curculigo orchioides Gaertn. (Family - Amaryllidaceae). Administration of Curculigoside enhanced the natural killer (NK) cell activity, antibody-dependent cell-mediated cytotoxicity and complement-mediated cytotoxicity in metastatic tumor-bearing animals, when compared to the untreated control animals. The compound was also found to be effective in reducing the levels of proinflammatory cytokines such as TNF-α, IL-1β, IL-6 and GM-CSF during metastasis. Besides these, levels of TH1 cytokines, such as IL-2 and IFN-γ, were significantly enhanced (p < 0.001) by Curculigoside administration and thereby reduces the metastatic lung colony formation along with an increased lifespan of the experimental animals. These studies provide an evidence for the stimulation of cell-mediated immune responses by Curculigoside against B16F10-induced metastatic tumor progression in experimental animals. PMID:27228189

  14. Mast Cell-Mediated Mechanisms of Nociception

    PubMed Central

    Aich, Anupam; Afrin, Lawrence B.; Gupta, Kalpna

    2015-01-01

    Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner. PMID:26690128

  15. Cell-mediated immunity in anorexia nervosa.

    PubMed Central

    Cason, J; Ainley, C C; Wolstencroft, R A; Norton, K R; Thompson, R P

    1986-01-01

    Twelve patients with anorexia nervosa were studied for cell-mediated immunity in terms of delayed hypersensitivity reactions to recall antigens, lymphocyte transformation responses to T-cell mitogens, and numbers of circulating leucocytes and T-cell subpopulations. Compared to controls, all patients had reduced cutaneous reactions and four were anergic. There was a mild leucopenia in patients and both T4+ and T3+ numbers were slightly reduced. Mean peak transformation responses for patients were slightly lower than controls for phytohaemagglutinin, but not for concanavalin A; however, patients required greater doses of mitogens to elicit peak transformation responses. Plasmas from patients did not contain inhibitors of transformation responses. We conclude that there are functional cellular abnormalities associated with the under-nutrition of anorexia nervosa. PMID:3742879

  16. Cell-mediated immunity in epidermodysplasia verruciformis.

    PubMed

    Gliński, W; Jablonska, S; Langner, A; Obalek, S; Haftek, M; Proniewska, M

    1976-01-01

    Investigations were performed in 6 cases of epidermodysplasia verruciformis and 2 healthy family members. Nonspecific cell-mediated immunity (CMI) was studied by measuring response to phytohemagglutinin (PHA) and concanavalin A (Con A), percentrages of E- and EAC-rosette-forming lymphocytes, bacterial skin tests, and allergic reactions to dinitrochloro-benzene (DNCB). Impairment of CMI was manifested by reduction in the percentage of E rosettes, and lowered response to PHA, and- to a lesser degree- to Con A. The immune response to DNCB sensitization was invariably negative. Impairment of CMI was greater in cases of long duration and with extensive lesions. The cases of similar duration and extent of lesions, which never showed tendency to tumor formation, were not different in CMI in comparison with cases with numerous tumors. Only in cases with very advanced tumors CMI was impaired parallel to the gravity of the patient's general condition. PMID:1017532

  17. LACK OF IMMUNODEPRESSION IN THE ANTIGEN SPECIFIC CELL MEDIATED IMMUNE RESPONSE AFTER CHALLENGE WITH VIRULENT OR VERY VIRULENT MAREK'S DISEASE VIRUS STRAINS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection with Marek's disease is known to produce a generalized "immunodepression" to the cell-mediated immune response as measured by reduced mitogen stimulation. We used the major histocompatibility complex restricted (MHC) cytotoxic T lymphocyte (CTL) response to the avian leukosis virus (ALV) ...

  18. Cell mediated immune regulation in autoimmunity.

    PubMed

    Gillissen, G; Pusztai-Markos, Z

    1979-01-01

    Autoimmunity is the term for the immune conditions characterized by a specific humoral or cell mediated response to the body's own tissues. The termination of the natural state of self tolerance may lead to immunopathological manifestations with clinical consequences, i.e. autoimmune diseases. In a very general sense, one may classify autoimmune diseases into two groups with respect to the underlying mechanism: 1. There are autoimmune diseases which develop in the presence of a normal intact regulation mechanism. 2. Another group whose development must be understood on the basis of a cellular dysfunction. In the first case, dequestered or semi-sequestered autoantigens are liberated as a consequence of exogenic influences inducing the sensitization of immunocompetent cells. The immune system then reacts with these autoantigens in the same way as with foreign substances. This kind of autoimmune disease will, however, not be dealt with here. In the second case, autoantigens are normally, i.e. in healthy individuals, accessible to the immunocompetent cells. To understand the reason for the development of an autoimmune reaction one must first clarify the mechanism of self tolerance. Then one must examine the way in which a break of this physiological state takes place. One of the major unanswered questions is the relative importance of antibody-mediated and cell-mediated immune mechanisms in the onset and further development of autoimmune diseases. Recently it has been suggested that a dysfunction at the cellular level might represent the basic cause which induces the termination of selftolerance. Most of the conceptions about the mechanism by which autoimmune diseases are triggered were gained through experiments with animals. It is, however, difficult to use these experimental results to explain human diseases; in humans many questions are still open. Undoubtedly, the mechanisms of induction and maintenance of self tolerance and also the ways in which autoimmune

  19. Cell-mediated immune deficiency in Hodgkin's disease.

    PubMed

    Kumar, R K; Penny, R

    1982-10-01

    Disturbances of the immune system frequently accompany the development of lymphomas in man. In the early stages of non-Hodgkin's lymphomas, abnormalities of immunological function are usually minimal, but impairment of both antibody- and cell-mediated immunity is often noted in advanced disease. In contrast, while antibody-mediated immune responses in patients with Hodgkin's disease usually remain intact until late in the course of the illness, cell-mediated immune dysfunction is an early and consistent feature. Here Rakesh Kumar and Ronald Penny discuss the abnormalities of cell-mediated immunity in Hodgkin's disease. PMID:25290229

  20. Cell-mediated immunity in experimental Nocardia asteroides infection.

    PubMed Central

    Sundararaj, T; Agarwal, S C

    1977-01-01

    Experimental mycetoma-like lesions developed in guinea pigs after subcutaneous injection of Nocardia asteroides. Although delayed hypersensitivity appeared earlier, increased macrophage migration inhibition and microbicidal activity appeared after 7 weeks. When the lesions healed, high cell-mediated immunity was present. Cell-mediated immunity was transferred to normal recipient guinea pigs from healed donor guinea pigs by spleen cell transfer. Recipient guinea pigs showed marked protection against challenge with N. asteroides. PMID:321348

  1. Suppression of cell-mediated immunity to challenge with P 815 mastocytoma in concanavalin A-treated mice.

    PubMed

    Ekstedt, R D; Merdian, D J

    1983-01-01

    C57Bl/6 (B6) mice allogeneic to the P 815 mastocytoma tumor cell line when treated with concanavalin A prior to and at frequent intervals following challenge intraperitoneally with 10(7) tumor cells showed a significant suppression of their cell-mediated immune response at 9-10 days when compared with untreated animals. Suppression of the immune response of mice syngeneic (DBA/2) or hybrid (BDF1) to the tumor was also evidenced by increased mortality rates in concanavalin A-treated animals. The suppression of cell-mediated cytotoxicity observed in B6 mice treated with concanavalin A could be reversed by pretreatment with 20 mg silica injected intraperitoneally 7 days prior to challenge. These results suggest that macrophages play a significant role in the concanavalin A-induced immune suppression observed in this in vivo tumor-host system. PMID:6297806

  2. Idiopathic pulmonary fibrosis: can cell mediated immunity markers predict clinical outcome?

    PubMed Central

    Meliconi, R; Lalli, E; Borzì, R M; Sturani, C; Galavotti, V; Gunella, G; Miniero, R; Facchini, A; Gasbarrini, G

    1990-01-01

    Most of the cells found in lung parenchyma in patients with idiopathic pulmonary fibrosis are activated T lymphocytes and macrophages. The serum levels of three markers of cell mediated immunity were measured in 20 patients with idiopathic pulmonary fibrosis, in 20 normal subjects and in 12 patients with sarcoidosis to evaluate their clinical and prognostic significance in idiopathic pulmonary fibrosis. The three markers were: soluble CD8 (from activated suppressor-cytotoxic lymphocytes), soluble interleukin (IL)-2 receptors (from activated T cells and macrophages), and neopterin (from activated macrophages). Patients with idiopathic pulmonary fibrosis had higher levels of all three markers than the control subjects. Soluble IL-2 receptor and neopterin tended to be lower (though not significantly) in patients with idiopathic pulmonary fibrosis than in those with sarcoidosis, whereas soluble CD8 was similar in the two groups of patients. No correlation was found between soluble IL-2 receptors or soluble CD8 and the clinical, radiological, and physiological measures of disease activity or with clinical outcome (after a mean follow up of 23 months). Tumour necrosis factor levels were also determined. Only 30% of patients with idiopathic pulmonary fibrosis or sarcoidosis had detectable circulating tumour necrosis factor; these patients had a lower percentage of bronchoalveolar lavage fluid neutrophils in their lavage fluid. Tumour necrosis factor levels did not correlate with clinical measures of severity or outcome. Thus our data support the hypothesis that cell mediated alveolitis occurs in idiopathic pulmonary fibrosis. They do not, however, provide evidence to support the use of these markers of cell mediated immunity to monitor the clinical course in these patients. PMID:2118691

  3. Astaxanthin stimulates cell-mediated and humoral immune responses in cats.

    PubMed

    Park, Jean Soon; Mathison, Bridget D; Hayek, Michael G; Massimino, Stefan; Reinhart, Gregory A; Chew, Boon P

    2011-12-15

    Astaxanthin is a potent antioxidant carotenoid and may play a role in modulating immune response in cats. Blood was taken from female domestic shorthair cats (8-9 mo old; 3.2 ± 0.04 kg body weight) fed 0, 1, 5 or 10mg astaxanthin daily for 12 wk to assess peripheral blood mononuclear cell (PBMC) proliferation response, leukocyte subpopulations, natural killer (NK) cell cytotoxic activity, and plasma IgG and IgM concentration. Cutaneous delayed-type hypersensitivity (DTH) response against concanavalin A and an attenuated polyvalent vaccine was assessed on wk 8 (prior to vaccination) and 12 (post-vaccination). There was a dose-related increase in plasma astaxanthin concentrations, with maximum concentrations observed on wk 12. Dietary astaxanthin enhanced DTH response to both the specific (vaccine) and nonspecific (concanavalin A) antigens. In addition, cats fed astaxanthin had heightened PBMC proliferation and NK cell cytotoxic activity. The population of CD3(+) total T and CD4(+) T helper cells were also higher in astaxanthin-fed cats; however, no treatment difference was found with the CD8(+) T cytotoxic and MHC II(+) activated lymphocyte cell populations. Dietary astaxanthin increased concentrations of plasma IgG and IgM. Therefore, dietary astaxanthin heightened cell-mediated and humoral immune responses in cats. PMID:21930306

  4. Cell-mediated response at the muscle phase of Trichinella pseudospiralis and Trichinella spiralis infections.

    PubMed

    Lee, K M; Ko, R C

    2006-06-01

    The cell-mediated response in BALB/c mice infected either by Trichinella pseudospiralis or Trichinella spiralis was compared at days 30-50 post-infection (muscle phase). The former species is non-encapsulated, whereas the latter is encapsulated in host muscles. The pattern of response against the two species was similar. Both species elicited T(H)0 or T(H)1/T(H)2 response, with the last one being dominant. Productions of interferon gamma (IFN-gamma), interleukin (IL)-4 and IL-5 were observed after antigenic restimulation of splenocytes from infected mice. No significant difference was observed between the levels of response to concanavalin A (Con-A) by the splenocytes from both infected and non-infected animals. There was a significant increase in serum IgG(1) and IgG(2a). Flow cytometric analysis revealed a marked proliferative response of splenocytes from infected mice to worm antigens, dominated by B (CD19) lymphoblasts. Only a few helper (CD4+) and cytotoxic (CD8+) T lymphoblasts were present. This was confirmed by an up-regulation of CD69, with a dominant expression on B lymphoblasts. In conclusion, the minimal or lack of intense cellular response against T. pseudospiralis in muscles is likely not due to depression of cell-mediated immunity. PMID:16489472

  5. Detection of cell mediated immune response to avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In birds, lymphomyeloid tissues develop from epithelial (Bursa of Fabricus or thymus) or mesenchymal tissue which are populated by heamatopoietic stem cells. These stem cells develop directly into immunologically competent B (bursa) and T (thymus) cells. Cell-mediated immunity (CMI) is a part of the...

  6. EFFECTS OF ENVIRONMENTAL CONTAMINANTS ON CELL MEDIATED IMMUNITY

    EPA Science Inventory

    The effect of lead and cadmium on cell-mediated immunity was studied in peritoneal macrophages, B-, and T-lymphocytes of mice. Lead and cadmium were administered in drinking water for 10 weeks in short-term experiments and up to 18 months to deal with immune responses in aged mic...

  7. Effect of Biophytum sensitivum on cell-mediated immune response in mice.

    PubMed

    Guruvayoorappan, C; Kuttan, G

    2007-01-01

    Effect of Biophytum sensitivum on cell-mediated immune response was studied in normal as well as Ehrlich ascites tumor bearing BALB/c mice. Administration of Biophytum sensitivum significantly enhanced the proliferation of splenocytes, thymocytes and bone marrow cells by stimulating the mitogenic potential of various mitogens such as Lipopolysaccharide (LPS), Concanavalin A (Con A), Phytohaemagglutinin (PHA) and Poke Weed Mitogen (PWM). Natural killer (NK) cell activity was enhanced significantly by Biophytum sensitivum in both the normal (43.6% cell lysis on day 5) and the tumor bearing group (48.2% cell lysis on day 5), and it was found to be earlier than tumor bearing control animals (maximum of 13.4% cell lysis on day 9). Antibody dependent cellular cytotoxicity (ADCC) was also enhanced significantly in both Biophytum treated normal (35% cell lysis on day 7) as well as tumor bearing animals (40.2% cell lysis on day 7) compared to untreated control tumor bearing animals (maximum of 12.3% cell lysis on day 11). An early antibody dependent complement mediated cytotoxicity (ACC) was also observed in the Biophytum treated normal (22.6% cell lysis, on day 15) and tumor bearing animals (26.4% cell lysis, on day 15). Results of our present study suggest the immunomodulatory property of Biophytum sensitivum. PMID:18075848

  8. Integrin receptors on tumor cells facilitate NK cell-mediated antibody-dependent cytotoxicity.

    PubMed

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J; Powers, Gordon D; Sato, Takami; Campbell, Kerry S; Sykulev, Yuri

    2014-08-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high antibody concentration, revealing a dose limiting effect. A similar effect was also observed with primary human NK cells. The effect was erased after IFN-γ treatment of tumor cells resulting in upregulation of ICAM-1. Furthermore, killing of the same tumor cells induced by Herceptin antibody was significantly impaired in the presence of CNTO 95Ala-Ala antibody variant that blocks αV integrins but is incapable of binding to CD16. These data suggest that αV integrins on tumor cells could compensate for the loss of ICAM-1 molecules, thereby facilitating ADCC by NK cells. Thus, NK cells could exercise cytolytic activity against ICAM-1 deficient tumor cells in the absence of proinflammatory cytokines, emphasizing the importance of NK cells in tumor-specific immunity at early stages of cancer. PMID:24810893

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

    PubMed Central

    Alderson, Kory L.; Sondel, Paul M.

    2011-01-01

    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. PMID:21660134

  10. Cord blood T cells mediate enhanced antitumor effects compared with adult peripheral blood T cells.

    PubMed

    Hiwarkar, Prashant; Qasim, Waseem; Ricciardelli, Ida; Gilmour, Kimberly; Quezada, Sergio; Saudemont, Aurore; Amrolia, Persis; Veys, Paul

    2015-12-24

    Unrelated cord blood transplantation (CBT) without in vivo T-cell depletion is increasingly used to treat high-risk hematologic malignancies. Following T-replete CBT, naïve CB T cells undergo rapid peripheral expansion with memory-effector differentiation. Emerging data suggest that unrelated CBT, particularly in the context of HLA mismatch and a T-replete graft, may reduce leukemic relapse. To study the role of CB T cells in mediating graft-versus-tumor responses and dissect the underlying immune mechanisms for this, we compared the ability of HLA-mismatched CB and adult peripheral blood (PB) T cells to eliminate Epstein-Barr virus (EBV)-driven human B-cell lymphoma in a xenogeneic NOD/SCID/IL2rg(null) mouse model. CB T cells mediated enhanced tumor rejection compared with equal numbers of PB T cells, leading to improved survival in the CB group (P < .0003). Comparison of CB T cells that were autologous vs allogeneic to the lymphoma demonstrated that this antitumor effect was mediated by alloreactive rather than EBV-specific T cells. Analysis of tumor-infiltrating lymphocytes demonstrated that CB T cells mediated this enhanced antitumor effect by rapid infiltration of the tumor with CCR7(+)CD8(+) T cells and prompt induction of cytotoxic CD8(+) and CD4(+) T-helper (Th1) T cells in the tumor microenvironment. In contrast, in the PB group, this antilymphoma effect is impaired because of delayed tumoral infiltration of PB T cells and a relative bias toward suppressive Th2 and T-regulatory cells. Our data suggest that, despite being naturally programmed toward tolerance, reconstituting T cells after unrelated T-replete CBT may provide superior Tc1-Th1 antitumor effects against high-risk hematologic malignancies. PMID:26450984

  11. Effect of space flight on cell-mediated immunity

    NASA Technical Reports Server (NTRS)

    Mandel, A. D.; Balish, E.

    1977-01-01

    The cell-mediated immune response to Listeria monocytogenes was studied in rats subjected to 20 days of flight aboard the Soviet biosatellite Kosmos 7820. Groups of rats were immunized with 1,000,000 formalin-killed Listeria suspended in Freunds Complete Adjuvant, 5 days prior to flight. Immunized rats subjected to the same environmental factors as the flight rats, except flight itself, and immunized and nonimmunized rats held in a normal animal colony served as controls. Following recovery, lymphocyte cultures were harvested from spleens of all rats, cultured in vitro in the presence of L. monocytogenes antigens, Phytohemagglutinin, Conconavlin A, or purified protein derivative (PPD), and measured for their uptake of H-3-thymidine. Although individual rats varied considerably, all flight and immunized control rats gave a blastogenic response to the Listeria antigens and PPD. With several mitogens, the lymphocytes of flight rats showed a significantly increased blastogenic response over the controls. The results of this study do not support a hypothesis of a detrimental effect of space flight on cell-mediated immunity. The data suggest a possible suppressive effect of stress and gravity on an in vitro correlate of cell-mediated immunity.

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

    PubMed

    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. PMID:25528359

  13. CIS is a potent checkpoint in NK cell-mediated tumor immunity.

    PubMed

    Delconte, Rebecca B; Kolesnik, Tatiana B; Dagley, Laura F; Rautela, Jai; Shi, Wei; Putz, Eva M; Stannard, Kimberley; Zhang, Jian-Guo; Teh, Charis; Firth, Matt; Ushiki, Takashi; Andoniou, Christopher E; Degli-Esposti, Mariapia A; Sharp, Phillip P; Sanvitale, Caroline E; Infusini, Giuseppe; Liau, Nicholas P D; Linossi, Edmond M; Burns, Christopher J; Carotta, Sebastian; Gray, Daniel H D; Seillet, Cyril; Hutchinson, Dana S; Belz, Gabrielle T; Webb, Andrew I; Alexander, Warren S; Li, Shawn S; Bullock, Alex N; Babon, Jeffery J; Smyth, Mark J; Nicholson, Sandra E; Huntington, Nicholas D

    2016-07-01

    The detection of aberrant cells by natural killer (NK) cells is controlled by the integration of signals from activating and inhibitory ligands and from cytokines such as IL-15. We identified cytokine-inducible SH2-containing protein (CIS, encoded by Cish) as a critical negative regulator of IL-15 signaling in NK cells. Cish was rapidly induced in response to IL-15, and deletion of Cish rendered NK cells hypersensitive to IL-15, as evidenced by enhanced proliferation, survival, IFN-γ production and cytotoxicity toward tumors. This was associated with increased JAK-STAT signaling in NK cells in which Cish was deleted. Correspondingly, CIS interacted with the tyrosine kinase JAK1, inhibiting its enzymatic activity and targeting JAK for proteasomal degradation. Cish(-/-) mice were resistant to melanoma, prostate and breast cancer metastasis in vivo, and this was intrinsic to NK cell activity. Our data uncover a potent intracellular checkpoint in NK cell-mediated tumor immunity and suggest possibilities for new cancer immunotherapies directed at blocking CIS function. PMID:27213690

  14. Possible involvement of soluble B7-H4 in T cell-mediated inflammatory immune responses.

    PubMed

    Kamimura, Yosuke; Kobori, Hiroko; Piao, Jinhua; Hashiguchi, Masaaki; Matsumoto, Koichiro; Hirose, Sachiko; Azuma, Miyuki

    2009-11-13

    B7-H4, a newly identified B7 family molecule, is reported to regulate T cell activation. However, the expression and function of B7-H4 remain controversial. Here, we demonstrated that B7-H4 expression in immune cells was undetectable at both the transcription and cell-surface protein levels. B7-H4 transfectants augmented anti-CD3 mAb-induced re-directed cytotoxicity and this was inhibited by anti-B7-H4 mAb. In a hapten-induced contact hypersensitivity model, treatment with anti-B7-H4 mAb at sensitization, but not at challenge, efficiently suppressed the ear swelling and CD8(+) T cell activation assessed by CD25 expression and IFN-gamma production. We found that cells expressing B7-H4 secreted soluble B7-H4 and the serum B7-H4 level increased with disease progression in lupus-prone and collagen-induced arthritis autoimmune mice and after the antigen challenge in allergic inflammatory diseases. Our results suggest a different action of B7-H4 in T cell-mediated inflammatory responses and the possible involvement of soluble B7-H4 in inflammatory immune responses. PMID:19723502

  15. Establishment of Stable, Cell-Mediated Immunity that Makes "Susceptible" Mice Resistant to Leishmania major

    NASA Astrophysics Data System (ADS)

    Bretscher, Peter A.; Wei, Guojian; Menon, Juthika N.; Bielefeldt-Ohmann, Helle

    1992-07-01

    Cell-mediated, but not antibody-mediated, immune responses protect humans against certain pathogens that produce chronic diseases such as leishmaniasis. Effective vaccination against such pathogens must therefore produce an immunological "imprint" so that stable, cell-mediated immunity is induced in all individuals after natural infection. BALB/c mice "innately susceptible" to Leishmania major produce antibodies after substantial infection. In the present study, "susceptible" mice injected with a small number of parasites mounted a cell-mediated response and acquired resistance to a larger, normally pathogenic, challenge. This vaccination strategy may be applicable in diseases in which protection is dependent on cell-mediated immunity.

  16. Depressed cell-mediated immunity in coeliac disease.

    PubMed Central

    Scott, B B; Losowsky, M S

    1976-01-01

    Fourteen coeliac patients on a gluten free diet (GFD) and 10 on a normal diet were studied by lymphocyte transformation in response to PHA to assess the integrity of cell-mediated immunity (CMI). Transformation was depressed in the majority taking a normal diet, with improvement after a GFD. In some patients the depression may have been due to a serum factor, as transformation was more nearly normal when the lymphocytes were cultured in pooled AB serum than in their own serum. There was no correlation between transformation and nutritional deficiencies. Mantoux tests were performed in some of these and other coeliac patients and there was a very significant reduction in the incidence of positive tests compared with controls. These findings provide evidence of depressed CMI in coeliac patients taking a normal diet with improvement on a GFD and may be of relevance to the high risk of malignancy in coeliac disease, further strengthening the case for a strict GFD. PMID:1087262

  17. Nonspecific cell-mediated immunity in patients with epidermodysplasia verruciformis.

    PubMed

    Pereira de Oliveira, Walmar Roncalli; Carrasco, Solange; Neto, Cyro Festa; Rady, Peter; Tyring, Stephen K

    2003-03-01

    Epidermodysplasia verruciformis (EV) is a rare disease that usually begins in childhood and is characterized by a generalized infection by human papilloma virus (HPV), frequent associations with cutaneous carcinomas, and abnormalities of cell-mediated immunity (CMI). We studied nonspecific CMI in 13 patients with EV by bacterial skin tests, allergic reactions to dinitrochlorobenzene (DNCB), measurement of responses to phytohemagglutinin (PHA), and quantification of T lymphocytes and T lymphocytes subsets in peripheral blood. Impairment of CMI was manifested by the cutaneous anergy to a variety of common skin antigens and, by the reduction of the lymphocyte transformation to PHA. There were no correlation between the severity of cases and abnormalities of CMI in our patients, however; the impairment of CMI was lower in cases of short duration, suggesting that the impairment of CMI in EV might reflect a long period of disease. PMID:12692356

  18. Electric Pulse Stimulation of Myotubes as an In Vitro Exercise Model: Cell-Mediated and Non-Cell-Mediated Effects

    PubMed Central

    Evers-van Gogh, Inkie J.A.; Alex, Sheril; Stienstra, Rinke; Brenkman, Arjan B.; Kersten, Sander; Kalkhoven, Eric

    2015-01-01

    Regular exercise has emerged as one of the best therapeutic strategies to prevent and treat type-2-diabetes. Exercise-induced changes in the muscle secretome, consisting of myokines and metabolites, may underlie the inter-organ communication between muscle and other organs. To investigate this crosstalk, we developed an in vitro system in which mouse C2C12 myotubes underwent electric pulse stimulation (EPS) to induce contraction. Subsequently the effects of EPS-conditioned media (EPS-CM) on hepatocytes were investigated. Here, we demonstrate that EPS-CM induces Metallothionein 1/2 and Slc30a2 gene expression and reduces Cyp2a3 gene expression in rat hepatocytes. When testing EPS-CM that was generated in the absence of C2C12 myotubes (non-cell EPS-CM) no decrease in Cyp2a3 expression was detected. However, similar inductions in hepatic Mt1/2 and Slc30a2 expression were observed. Non-cell EPS-CM were also applied to C2C12 myotubes and compared to C2C12 myotubes that underwent EPS: here changes in AMPK phosphorylation and myokine secretion largely depended on EPS-induced contraction. Taken together, these findings indicate that EPS can alter C2C12 myotube function and thereby affect gene expression in cells subjected to EPS-CM (Cyp2a3). However, EPS can also generate non-cell-mediated changes in cell culture media, which can affect gene expression in cells subjected to EPS-CM too. While EPS clearly represents a valuable tool in exercise research, care should be taken in experimental design to control for non-cell-mediated effects. PMID:26091097

  19. Cell-mediated immune response of patients with meningiomas defined in vitro by a [3H]proline microcytotoxicity test.

    PubMed Central

    Pees, H W; Seidel, B

    1976-01-01

    Cell-mediated cytotoxicity (CTX) of meningioma patients was assessed postoperatively by a [3H]proline microcytotoxicity test. Autologous and allogeneic tumour cells were used for prelabelling with isotope and peripheral blood lymphocytes added in a ratio of 200:1. After 60 hg the plates were washed and residual CMP counted. Control target cells consisted of normal skin fibroblasts. CTX was calculated in percentage reduction compared to cultures incubated with control lymphocytes. Specific CTX on meningioma cells (i.e. not destroying control cells) greater than 20% was considered 'positive' if significant at P less than 0-05. Fifteen of twenty-three meningiomas showed specific CTX (65%). Among eight CNS tumours of different type and thirteen non-malignant diseases and normals only three (14%) were specifically cytotoxic for meningioma cells. A cross-reaction could be demonstrated between autologous and allogeneic meningioma target cells. However, no activity of lymphocytes from patients with meningiomas on glioblastoma cells and foetal brain tissue could be found at the ratio used for evaluation. Evidence is presented indicating that a cellular immune response as measured in the microcytotoxic test may be dependent on a residual or recurrent tumour in the body. PMID:1277580

  20. Cell-mediated immunity to insulin: a new criterion for differentiation of diabetes mellitus?

    PubMed

    Asfandiyarova, Nailya S

    2012-03-01

    Any classification is a step forward and it should help to determine the reason, the course, the prognosis, the treatment of a disease. The current classification of diabetes mellitus (DM) is really very convenient for work, but it has some drawbacks, and the absence of differentiation of type 2 diabetes is the main. The problem is the absence of an adequate criterion, based on pathogenesis for differentiation. We suppose that cell mediated immunity (CMI) to insulin plays the central role in the diabetes genesis. Autoimmune process may be triggered by viruses family Paramyxoviridae, in 10-20% of type 1 diabetes patients the disease is a consequence of direct cytotoxic effect of other viruses to the islet cells of pancreas. In acute phase of viral infection (measles, mumps, parainfluenza) CMI against viruses is developed, in some patients CMI to insulin appeared. We suppose that autoimmune reactions in these cases are the result of cross reaction between viral antigens and insulin. The majorities of patients suppress these reactions and recover from acute infection diseases with the antiviral immunity development and without any complications. Other patients are not able to suppress autoimmune reactions to insulin and pathological process is triggered. Type 1A diabetes is a result of direct CMI to insulin, and this process is responsible for beta-cells destruction; may be type 1B DM is due to the direct cytotoxic effect of other viruses or toxins to them. Some patients with acute viral infection cannot destroy the aggressive clone and they suppress autoimmune reaction to insulin by prostaglandin synthesizing cells (PGSC) or сells with histamine receptors (CHR). As a result of this process the insulin resistance is developed, because these cells or their cytokines form a block to the insulin receptors not only on immunocompetent cells, but in insulin sensitive tissues too. Patients with different reactions to insulin have different courses and outcomes of DM. We

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

    PubMed

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

    2016-01-01

    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. PMID:26797607

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

    PubMed Central

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

    2016-01-01

    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. PMID:26797607

  3. Carbonic anhydrase enzymes regulate mast cell-mediated inflammation.

    PubMed

    Henry, Everett K; Sy, Chandler B; Inclan-Rico, Juan M; Espinosa, Vanessa; Ghanny, Saleena S; Dwyer, Daniel F; Soteropoulos, Patricia; Rivera, Amariliz; Siracusa, Mark C

    2016-08-22

    Type 2 cytokine responses are necessary for the development of protective immunity to helminth parasites but also cause the inflammation associated with allergies and asthma. Recent studies have found that peripheral hematopoietic progenitor cells contribute to type 2 cytokine-mediated inflammation through their enhanced ability to develop into mast cells. In this study, we show that carbonic anhydrase (Car) enzymes are up-regulated in type 2-associated progenitor cells and demonstrate that Car enzyme inhibition is sufficient to prevent mouse mast cell responses and inflammation after Trichinella spiralis infection or the induction of food allergy-like disease. Further, we used CRISPR/Cas9 technology and illustrate that genetically editing Car1 is sufficient to selectively reduce mast cell development. Finally, we demonstrate that Car enzymes can be targeted to prevent human mast cell development. Collectively, these experiments identify a previously unrecognized role for Car enzymes in regulating mast cell lineage commitment and suggest that Car enzyme inhibitors may possess therapeutic potential that can be used to treat mast cell-mediated inflammation. PMID:27526715

  4. Cell-mediated immunity in the course of cervical ectropion.

    PubMed

    De Luca Brunori, I; Facchini, V; Filippeschi, M; Battini, L; Giusti, G; Romani, L; Scida, P; Urbano, M

    1994-01-01

    In the present study we evaluated cellular immunitary response in course of asymptomatic ectropion. Biopsies of the injured and healthy zones of the exocervix were carried out. All biopsies were examined by an immuno-histo-chemical method (Avidin-Biotin Complex, ABC) with monoclonal antibodies, in order to phenotype T lymphocytic subpopulations, in particular T helper lymphocytes (CD4), T suppressor lymphocytes (CD8) and Langerhans cells (CD1), which are basic elements of the monocytic-macrophagic series. Our preliminary findings showed a reduction of CD4, CD8 and CD1 lymphocytic subpopulations in ectropion zones, while these subpopulations are normally present in healthy zones of the exocervix. These findings support the hypothesis that, in ectropion, as in HPV infections and in CIN, a localized immuno-deficiency may appear and depress immuno-surveillance and cell-mediated response. In conclusion, it may be supposed that ectropion represents a non-stable lesion, which therefore needs suitable therapeutic intervention. PMID:7915218

  5. B-Cell-Mediated Strategies to Fight Chronic Allograft Rejection

    PubMed Central

    Dalloul, Ali

    2013-01-01

    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 1 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 allograft

  6. Cell-mediated immune responses to respiratory syncytial virus infection

    PubMed Central

    Geevarghese, Bessey; Weinberg, Adriana

    2014-01-01

    We evaluated the cell-mediated immune (CMI) response to RSV acute infection including the magnitude, kinetics and correlates with morbidity and age. Twenty-nine RSV-infected patients with mean ± SD age of 15 ± 14 months were enrolled during their first week of disease. Th1, Th2, Th9, Th17 and Th22 responses were measured at entry and 2 and 6 weeks later. All subjects were hospitalized for a median (range) of 5 (3–11) days. RSV-specific effector and memory Th1 CMI measured by lymphocyte proliferation and IFNγ ELISPOT significantly increased over time (P ≤ 0.03). In contrast, Th22 responses decreased over time (P ≤ 0.03). Other changes did not reach statistical significance. The severity of RSV disease measured by the length of hospitalization positively correlated with the magnitude of Th9, Th22 and TNFα inflammatory responses (rho ≥ 0.4; P ≤ 0.04) and negatively with memory CMI (rho = –0.45; P = 0.04). The corollary of this observation is that robust Th1 and/or low Th9, Th22, and TNFα inflammatory responses may be associated with efficient clearance of RSV infection and therefore desirable characteristics of an RSV vaccine. Young age was associated with low memory and effector Th1 responses (rho ≥ 0.4; P ≤ 0.04) and high Th2, Th9, Th17, Th22 and TNFα inflammatory responses (rho ≤ –0.4; P ≤ 0.04), indicating that age at vaccination may be a major determinant of the CMI response pattern. PMID:24513666

  7. Siglecs as targets for therapy in immune cell mediated disease

    PubMed Central

    O’Reilly, Mary K.; Paulson, James C.

    2010-01-01

    The sialic acid-binding immunoglobulin-like lectins (siglecs) comprise a family of receptors that are differentially expressed on leukocytes and other immune cells. The restricted expression of several siglecs to one or a few cell types makes them attractive targets for cell-directed therapies. The anti-CD33 (Siglec-3) antibody Gemtuzumab (Mylotarg™) is approved for treatment of acute myeloid leukemia (AML), and antibodies targeting CD22 (Siglec-2) are currently in clinical trials for treatment of B cell non-Hodgkins lymphomas and autoimmune diseases. Because siglecs are endocytic receptors, they are well suited for a ‘Trojan horse’ strategy, whereby therapeutic agents conjugated to an antibody, or multimeric glycan ligand, bind to the siglec and are efficiently carried into the cell. Although the rapid internalization of unmodified siglec antibodies reduces their utility for induction of antibody-dependent cellular cytotoxicity (ADCC) or complement-mediated cytotoxicity (CDC), antibody binding of Siglec-8, Siglec-9, and CD22 have been demonstrated to induce apoptosis of eosinophils, neutrophils, and depletion of B cells, respectively. Here we review the properties of siglecs that make them attractive for cell-targeted therapies. PMID:19359050

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  9. A virus-sensitive suppressor cell is involved in the regulation of human allospecific T cell-mediated cytotoxicity

    SciTech Connect

    Muluk, S.C.; Bernstein, D.C.; Shearer, G.M. )

    1989-10-01

    The in vitro generation of allospecific CTL by human PBMC was enhanced 4- to 16-fold by sequential plastic and nylon wool adherence, which depleted the PBMC of macrophages and B cells. The enhanced CTL response was suppressed by adding back irradiated, unfractionated PBMC or adherent cells to the depleted cells. This finding suggests that the enhanced CTL response was not simply a consequence of enrichment of T cells, but was instead due to active suppression by radioresistant cells contained in the adherent fraction. Of note is the finding that, unlike the CTL response, the proliferative response to allostimulation was not affected by the removal of adherent cells. The suppressor function could be abrogated by preincubation of irradiated PBMC with influenza A virus before the coculture with depleted cells. Furthermore, costimulation of unfractionated PBMC with influenza A virus and allogeneic stimulators augmented allospecific CTL activity. Thus, in the adherent fraction of human PBMC, there appears to be a native suppressor population that can be functionally inactivated by virus. This result may account for the clinical observation of increased allograft rejection after certain viral infections.

  10. PTEN-mRNA engineered mesenchymal stem cell-mediated cytotoxic effects on U251 glioma cells

    PubMed Central

    GUO, XING RONG; HU, QIN YONG; YUAN, YA HONG; TANG, XIANG JUN; YANG, ZHUO SHUN; ZOU, DAN DAN; BIAN, LIU JIAO; DAI, LONG JUN; LI, DONG SHENG

    2016-01-01

    Mesenchymal stem cells (MSCs) have been considered to have potential as ideal carriers for the delivery of anticancer agents since the capacity for tumor-oriented migration and integration was identified. In contrast to DNA-based vectors, mRNA synthesized in vitro may be readily transfected and is mutagenesis-free. The present study was performed in order to investigate the effects of phosphatase and tensin homolog (PTEN) mRNA-engineered MSCs on human glioma U251 cells under indirect co-culture conditions. PTEN-bearing mRNA was generated by in vitro transcription and was transfected into MSCs. The expression of PTEN in transfected MSCs was detected by immunoblotting, and the migration ability of MSCs following PTEN-bearing mRNA transfection was verified using Transwell co-cultures. The indirect co-culture was used to determine the effects of PTEN-engineered MSCs on the viability of U251 glioma cells by luminescence and fluorescence microscopy. The synthesized PTEN mRNA was expressed in MSCs, and the expression was highest at 24 h subsequent to transfection. An enhanced migration rate was observed in MSCs transfected with PTEN mRNA compared with non-transfected MSCs (P<0.05). A significant inhibition of U251 cells was observed when the cells were cultured with conditioned medium from PTEN mRNA-engineered MSCs (P<0.05). The results suggested that anticancer gene-bearing mRNA synthesized in vitro is capable of being applied to a MSC-mediated anticancer strategy for the treatment of glioblastoma patients. PMID:27073544

  11. Generation of BiKEs and TriKEs to Improve NK Cell-Mediated Targeting of Tumor Cells.

    PubMed

    Felices, Martin; Lenvik, Todd R; Davis, Zachary B; Miller, Jeffrey S; Vallera, Daniel A

    2016-01-01

    Cancer immunotherapies have gained significant momentum over the past decade, particularly with the advent of checkpoint inhibitors and CAR T-cells. While the latter personalized targeted immunotherapy has revolutionized the field, a need for off-the-shelf therapies remains. The ability of NK cells to quickly lyse antibody-coated tumors and potently secrete cytokines without prior priming has made NK cells ideal candidates for antigen-specific immunotherapy. NK cells have been targeted to tumors through two main strategies: mono-specific antibodies and bi/tri-specific antibodies. Mono-specific antibodies drive NK cell antibody-dependent cell-mediated cytotoxicity (ADCC) of tumor cells. Bi/tri-specific antibodies drive re-directed lysis of tumor cells through binding of a tumor antigen and direct binding and crosslinking of the CD16 receptor on NK cells, thus bypassing the need for binding of the Fc portion of mono-specific antibodies. This chapter focuses on the generation of bi- and tri-specific killer engagers (BiKEs and TriKEs) meant to target NK cells to tumors. BiKEs and TriKEs are smaller molecules composed of 2-3 variable portions of antibodies with different specificities, and represent a novel and more versatile strategy compared to traditional bi- and tri-specific antibody platforms. PMID:27177679

  12. The requirement for DNAM-1, NKG2D, and NKp46 in the natural killer cell-mediated killing of myeloma cells.

    PubMed

    El-Sherbiny, Yasser M; Meade, Josephine L; Holmes, Tim D; McGonagle, Dennis; Mackie, Sarah L; Morgan, Ann W; Cook, Gordon; Feyler, Sylvia; Richards, Stephen J; Davies, Faith E; Morgan, Gareth J; Cook, Graham P

    2007-09-15

    Recent evidence suggests a role for natural killer (NK) cells in the control of multiple myeloma. We show that expression of the NK cell receptor DNAM-1 (CD226) is reduced on CD56(dim) NK cells from myeloma patients with active disease compared with patients in remission and healthy controls. This suggested that this receptor might play a role in NK-myeloma interactions. The DNAM-1 ligands Nectin-2 (CD112) and the poliovirus receptor (PVR; CD155) were expressed by most patient myeloma samples analyzed. NK killing of patient-derived myelomas expressing PVR and/or Nectin-2 was DNAM-1 dependent, revealing a functional role for DNAM-1 in myeloma cell killing. In myeloma cell lines, cell surface expression of PVR was associated with low levels of NKG2D ligands, whereas cells expressing high levels of NKG2D ligands did not express PVR protein or mRNA. Furthermore, NK cell-mediated killing of myeloma cell lines was dependent on either DNAM-1 or NKG2D but not both molecules. In contrast, the natural cytotoxicity receptor NKp46 was required for the killing of all myeloma cell lines analyzed. Thus, DNAM-1 is important in the NK cell-mediated killing of myeloma cells expressing the cognate ligands. The importance of NKp46, NKG2D, and DNAM-1 in myeloma killing mirrors the differential expression of NK cell ligands by myeloma cells, reflecting immune selection during myeloma disease progression. PMID:17875681

  13. Effects of feed supplementation with glycine chelate and iron sulfate on selected parameters of cell-mediated immune response in broiler chickens.

    PubMed

    Jarosz, Łukasz; Kwiecień, Małgorzata; Marek, Agnieszka; Grądzki, Zbigniew; Winiarska-Mieczan, Anna; Kalinowski, Marcin; Laskowska, Ewa

    2016-08-01

    Because little is known about the impact of chelated (Fe-Gly, Fe-Gly+F) and inorganic (FeSO4, FeSO4+F) iron products on immune response parameters in broiler chickens, the objective of the study was to determine the effects of inorganic and organic forms of iron on selected parameters of the cell-mediated immune response in broiler chickens by assessing the percentage of CD3(+)CD4(+), CD3(+)CD8(+), CD25(+), and MHC Class II lymphocytes, as well as the CD4(+)/CD8(+) ratio and IL-2 concentration in the peripheral blood. The experiments were conducted using 50day-old Ross 308 roosters. The test material was peripheral blood. Flow cytometry was used to determine selected cell-mediated immune response parameters. The results obtained indicate that the use of iron chelates in the diet of broiler chickens may stimulate cellular defense mechanisms. As a result of the experiment an increase was observed in the percentage of Th1, mainly T CD4(+) and T CD8(+). It was also noted that application of chelated iron can increase production of T CD8(+) cytotoxic cells and IL-2, which promotes the body's natural response to developing inflammation. There were no changes in T CD4(+), T CD8(+), T CD25(+) or MHC II lymphocyte subpopulations in the chickens following application of the inorganic form of iron. PMID:27473977

  14. NK Cell and Ig Interplay in Defense against Herpes Simplex Virus Type 1: Epistatic Interaction of CD16A and IgG1 Allotypes of Variable Affinities Modulates Antibody-Dependent Cellular Cytotoxicity and Susceptibility to Clinical Reactivation.

    PubMed

    Moraru, Manuela; Black, Laurel E; Muntasell, Aura; Portero, Francisca; López-Botet, Miguel; Reyburn, Hugh T; Pandey, Janardan P; Vilches, Carlos

    2015-08-15

    HSV-1 latently infects most humans, causing a variable clinical picture that depends, in part, on host genetic factors. Both IgG and its cellular FcRs, CD16A and CD32A-C (encoded by FCGR3A and FCGR2A-C, respectively, on chromosome 1), display polymorphisms that could affect their defensive function. Of potential relevance are a FCGR3A dimorphism resulting in CD16A-valine/phenylalanine-158 allotypes with different IgG affinity, variations conditioning NK cell expression of CD32B or CD32C, and IgG1 H chain (IGHG1) and kappa-chain (IGKC) polymorphisms determining allotypes designated G1m and Km. In this study, we assessed the contribution of Ig genetic variations and their interaction with FcR polymorphism to HSV-1 susceptibility, as well as their impact on NK cell-mediated Ab-dependent cellular cytotoxicity (ADCC). Our results show an epistatic interaction between IGHG1 and FCGR3A such that the higher affinity CD16A-158V/V genotype associates with an asymptomatic course of HSV-1 infection only in homozygotes for G1m3. Furthermore, CD16A-158V and G1m3 allotypes enhanced ADCC against opsonized HSV-1-infected fibroblasts. Conversely, Km allotypes and CD32B or CD32C expression on NK cells did not significantly influence HSV-1 susceptibility or ADCC. NK cells degranulating against immune serum-opsonized HSV-1-infected fibroblasts had heterogeneous phenotypes. Yet, enhanced ADCC was observed among NK cells showing a differentiated, memory-like phenotype (NKG2C(bright)NKG2A(-)CD57(+)FcRγ(-)), which expand in response to human CMV. These results extend our knowledge on the importance of immunogenetic polymorphisms and NK cell-Ab interplay in the host response against HSV-1 and point to the relevance of interactions between immune responses elicited during chronic coinfection by multiple herpesviruses. PMID:26179905

  15. Suppression of cell-mediated immunity after infection with attenuated rubella virus.

    PubMed Central

    Ganguly, R; Cusumano, C L; Waldman, R H

    1976-01-01

    The effects of attenuated rubella virus infection upon cell-mediated immunity of human volunteers were studied. The volunteers received the vaccine either by nose drops or by the subcutaneous route. Changes in cell-mediated immunity in terms of delayed cutaneous sensitivity to recall antigens, phytohemagglutination stimulation, and spontaneous migration inhibitory factor-like activity were studied at various time periods after infection. Spontaneous migration inhibitory factor-like activity was studied on supernatants of the lymphocytes obtained from the volunteers and incubated for 72 h in the absence of any antigens. A significant proportion of the volunteers showed suppression of one or more parameters of cell-medicated immunity tested by week 2 of infection compared to the control; however, there was no correlation between suppression of the various parameters studied. No difference was noticed in the incidence of cell-mediated immunity suppression between nose drops and subcutaneous route groups. PMID:770329

  16. Assessing humoral and cell-mediated immune response in Hawaiian green turtles, Chelonia mydas

    USGS Publications Warehouse

    Work, T.M.; Balazs, G.H.; Rameyer, R.A.; Chang, S.P.; Berestecky, J.

    2000-01-01

    Seven immature green turtles, Chelonia mydas, captured from Kaneohe Bay on the island of Oahu were used to evaluate methods for assessing their immune response. Two turtles each were immunized intramuscularly with egg white lysozyme (EWL) in Freunda??s complete adjuvant, Gerbu, or ISA-70; a seventh turtle was immunized with saline only and served as a control. Humoral immune response was measured with an indirect enzyme linked immunosorbent assay (ELISA). Cell-mediated immune response was measured using in vitro cell proliferation assays (CPA) using whole blood or peripheral blood mononuclear cells (PBM) cultured with concanavalin A (ConA), phytohaemagglutinin (PHA), or soluble egg EWL antigen. All turtles, except for one immunized with Gerbu and the control, produced a detectable humoral immune response by 6 weeks which persisted for at least 14 weeks after a single immunization. All turtles produced an anamnestic humoral immune response after secondary immunization. Antigen specific cell-mediated immune response in PBM was seen in all turtles either after primary or secondary immunization, but it was not as consistent as humoral immune response; antigen specific cell-mediated immune response in whole blood was rarely seen. Mononuclear cells had significantly higher stimulation indices than whole blood regardless of adjuvant, however, results with whole blood had lower variability. Both Gerbu and ISA-70 appeared to potentiate the cell-mediated immune response when PBM or whole blood were cultured with PHA. This is the first time cell proliferation assays have been compared between whole blood and PBM for reptiles. This is also the first demonstration of antigen specific cell-mediated response in reptiles. Cell proliferation assays allowed us to evaluate the cell-mediated immune response of green turtles. However, CPA may be less reliable than ELISA for detecting antigen specific immune response. Either of the three adjuvants appears suitable to safely elicit a

  17. Cell mediated immunity to corn starch in starch-induced granulomatous peritonitis.

    PubMed

    Goodacre, R L; Clancy, R L; Davidson, R A; Mullens, J E

    1976-03-01

    Two patients with histologically diagnosed starch induced granulomatous peritonitis (SGP) have been shown to have cell mediated immunity to corn starch using the techniques of macrophage migration inhibition and lymphocyte DNA synthesis. Control groups of normal subjects, patients with uncomplicated laparotomy, and patients with Crohn's disease were negative in both tests. Lymphocytes from two patients with band adhesions, one of whom had biopsy evidence of a granulomatous reaction to starch, were sensitized to starch. Cell mediated immunity to starch may contribute to the pathogenesis of SGP, and some band adhesions may be a chronic low grade manifestation of this disorder. PMID:1269987

  18. KERATINOCYTE CELL-MEDIATED MUTAGENESIS ASSAY: CORRELATION WITH IN VIVO TUMOR STUDIES

    EPA Science Inventory

    A murine keratinocyte cell-mediated mutagenesis assay was characterized and examined as an in vitro model system for studying the biotransformation of promutagens/procarcinogens by mouse skin. The assay used living cultured newborn SENCAR keratinocytes for the metabolic activatio...

  19. CALORIE RESTRICTION ENHANCES T CELL MEDIATED IMMUNE RESPONSE IN OVERWEIGHT MEN AND WOMEN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is well known that dietary energy restriction prolongs lifespan and enhances immune responsiveness in a wide range of laboratory animals. However, information on the applicability of these results to humans is limited. In this study we examined the effects of calorie restriction on T cell mediate...

  20. Genetic diversity predicts pathogen resistance and cell-mediated immunocompetence in house finches

    PubMed Central

    Hawley, Dana M; Sydenstricker, Keila V; Kollias, George V; Dhondt, André A

    2005-01-01

    Evidence is accumulating that genetic variation within individual hosts can influence their susceptibility to pathogens. However, there have been few opportunities to experimentally test this relationship, particularly within outbred populations of non-domestic vertebrates. We performed a standardized pathogen challenge in house finches (Carpodacus mexicanus) to test whether multilocus heterozygosity across 12 microsatellite loci predicts resistance to a recently emerged strain of the bacterial pathogen, Mycoplasma gallisepticum (MG). We simultaneously tested whether the relationship between heterozygosity and pathogen susceptibility is mediated by differences in cell-mediated or humoral immunocompetence. We inoculated 40 house finches with MG under identical conditions and assayed both humoral and cell-mediated components of the immune response. Heterozygous house finches developed less severe disease when infected with MG, and they mounted stronger cell-mediated immune responses to phytohaemagglutinin. Differences in cell-mediated immunocompetence may, therefore, partly explain why more heterozygous house finches show greater resistance to MG. Overall, our results underscore the importance of multilocus heterozygosity for individual pathogen resistance and immunity. PMID:17148199

  1. Cell-Mediated Immune Function and Cytokine Regulation During Space Flight

    NASA Technical Reports Server (NTRS)

    Sams, Clarence F.; Pierson, Duane L.; Paloski, W. H. (Technical Monitor)

    2000-01-01

    The changes in immune function which occur during space flight potentially expose the crews to an increased risk for development of illness. Decreased cellular immune function has been repeatedly documented after space flight and confirmed during flight by in vivo delayed-type hypersensitivity testing. However, correlation of immune changes with a clinically significant risk factor has not yet been performed. Our hypothesis is that space flight induces a decrease in cell-mediated immune function accompanied by a shift from a type 1 cytokine pattern (favoring cell-mediated immunity) to a type 2 cytokine pattern (favoring humoral immunity). We further hypothesize that reactivation of latent viruses will occur during space flight in association with the decreased cellular immunity. To test these hypotheses, we will determine the effects of space flight on cell-mediated immunity and viral reactivation. We will utilize delayed-type hypersensitivity testing as an in vivo measure of integrated cell-mediated immune function. The production of cytokines and immunoregulatory factors by lymphocytes and monocytes will be measured to determine whether changes in cytokine patterns are associated with the space flight-induced immune dysregulation. Correlation of antigen-specific immune changes with reactivation of latent herpes viruses will be determined by measuring peripheral levels of viral (CMV, VZV, EBV) antigen-specific T cells and comparing to the levels of EBV-infected B-cells by fluorescence in situ hybridization and flow cytometry. A comparison of cell-mediated immune function, cytokine regulation and viral reactivation will provide new insights into crew member health risks during flight.

  2. Augmented IFN-γ and TNF-α Induced by Probiotic Bacteria in NK Cells Mediate Differentiation of Stem-Like Tumors Leading to Inhibition of Tumor Growth and Reduction in Inflammatory Cytokine Release; Regulation by IL-10

    PubMed Central

    Bui, Vickie T.; Tseng, Han-Ching; Kozlowska, Anna; Maung, Phyu Ou; Kaur, Kawaljit; Topchyan, Paytsar; Jewett, Anahid

    2015-01-01

    Our previous reports demonstrated that the magnitude of natural killer (NK) cell-mediated cytotoxicity correlate directly with the stage and level of differentiation of tumor cells. In addition, we have shown previously that activated NK cells inhibit growth of cancer cells through induction of differentiation, resulting in the resistance of tumor cells to NK cell-mediated cytotoxicity through secreted cytokines, as well as direct NK-tumor cell contact. In this report, we show that in comparison to IL-2 + anti-CD16mAb-treated NK cells, activation of NK cells by probiotic bacteria (sAJ2) in combination with IL-2 and anti-CD16mAb substantially decreases tumor growth and induces maturation, differentiation, and resistance of oral squamous cancer stem cells, MIA PaCa-2 stem-like/poorly differentiated pancreatic tumors, and healthy stem cells of apical papillae through increased secretion of IFN-γ and TNF-α, as well as direct NK-tumor cell contact. Tumor resistance to NK cell-mediated killing induced by IL-2 + anti-CD16mAb + sAJ2-treated NK cells is induced by combination of IFN-γ and TNF-α since antibodies to both, and not each cytokine alone, were able to restore tumor sensitivity to NK cells. Increased surface expression of CD54, B7H1, and MHC-I on NK-differentiated tumors was mediated by IFN-γ since the addition of anti-IFN-γ abolished their increase and restored the ability of NK cells to trigger cytokine and chemokine release; whereas differentiated tumors inhibited cytokine release by the NK cells. Monocytes synergize with NK cells in the presence of probiotic bacteria to induce regulated differentiation of stem cells through secretion of IL-10 resulting in resistance to NK cell-mediated cytotoxicity and inhibition of cytokine release. Therefore, probiotic bacteria condition activated NK cells to provide augmented differentiation of cancer stem cells resulting in inhibition of tumor growth, and decreased inflammatory cytokine release. PMID

  3. Tumors Escape CD4+ T-cell-Mediated Immunosurveillance by Impairing the Ability of Infiltrating Macrophages to Indirectly Present Tumor Antigens.

    PubMed

    Tveita, Anders Aune; Schjesvold, Fredrik; Haabeth, Ole Audun; Fauskanger, Marte; Bogen, Bjarne

    2015-08-15

    Tumors cells can escape cytotoxic CD8+ T cells by preventing MHC I display of tumor antigens. It is unknown how tumors evade CD4+ T-cell responses, but because many tumor cells lack MHC II expression, novel mechanisms would be required. We have investigated this issue in a model in which MHC II(NEG) myeloma cells secrete a monoclonal Ig containing a V region L chain (VL) epitope recognized by CD4+ T cells. Infiltrating macrophages process and present the secreted tumor antigen to Th1 cells, resulting in induction of macrophage cytotoxicity and apparent rejection of the tumor. Despite long-term tumor protection in VL-specific T-cell receptor transgenic mice, we here describe that some myeloma cells persisted in a dormant state and, eventually, formed expanding tumors. Escape tumor cells maintained their secretion of complete (H+L) monoclonal Ig with unchanged sequence, while secretion of surplus free L chain was severely diminished. Although free L chains were efficiently processed and presented by tumor-infiltrating macrophages to CD4+ T cells, complete (H+L) monoclonal Ig was not. Forced overexpression of free L chain secretion reinstated tumor rejection. These results show that tumors can escape CD4+ T-cell-mediated rejection by impairing indirect presentation of tumor antigen by infiltrating macrophages. This occurs through a novel mechanism of immunoediting, in which modulation of the quaternary structure of the secreted tumor-specific antigen reduces its immunogenicity. PMID:26038231

  4. Induction of Potent Humoral and Cell-Mediated Immune Responses by Attenuated Vaccinia Virus Vectors with Deleted Serpin Genes

    PubMed Central

    Legrand, Fatema A.; Verardi, Paulo H.; Jones, Leslie A.; Chan, Kenneth S.; Peng, Yue; Yilma, Tilahun D.

    2004-01-01

    Vaccinia virus (VV) has been effectively utilized as a live vaccine against smallpox as well as a vector for vaccine development and immunotherapy. Increasingly there is a need for a new generation of highly attenuated and efficacious VV vaccines, especially in light of the AIDS pandemic and the threat of global bioterrorism. We therefore developed recombinant VV (rVV) vaccines that are significantly attenuated and yet elicit potent humoral and cell-mediated immune responses. B13R (SPI-2) and B22R (SPI-1) are two VV immunomodulating genes with sequence homology to serine protease inhibitors (serpins) that possess antiapoptotic and anti-inflammatory properties. We constructed and characterized rVVs that have the B13R or B22R gene insertionally inactivated (vΔB13R and vΔB22R) and coexpress the vesicular stomatitis virus glycoprotein (v50ΔB13R and v50ΔB22R). Virulence studies with immunocompromised BALB/cBy nude mice indicated that B13R or B22R gene deletion decreases viral replication and significantly extends time of survival. Viral pathogenesis studies in immunocompetent CB6F1 mice further demonstrated that B13R or B22R gene inactivation diminishes VV virulence, as measured by decreased levels of weight loss and limited viral spread. Finally, rVVs with B13R and B22R deleted elicited potent humoral, T-helper, and cytotoxic T-cell immune responses, revealing that the observed attenuation did not reduce immunogenicity. Therefore, inactivation of immunomodulating genes such as B13R or B22R represents a general method for enhancing the safety of rVV vaccines while maintaining a high level of immunogenicity. Such rVVs could serve as effective vectors for vaccine development and immunotherapy. PMID:14990697

  5. The NKG2D-IL-15 signaling pathway contributes to T-cell mediated pathology in inflammatory myopathies.

    PubMed

    Ruck, Tobias; Bittner, Stefan; Afzali, Ali Maisam; Göbel, Kerstin; Glumm, Sarah; Kraft, Peter; Sommer, Claudia; Kleinschnitz, Christoph; Preuße, Corinna; Stenzel, Werner; Wiendl, Heinz; Meuth, Sven G

    2015-12-22

    NKG2D is an activating receptor on T cells, which has been implicated in the pathogenesis of autoimmune diseases. T cells are critically involved in idiopathic inflammatory myopathies (IIM) and have been proposed as specific therapeutic targets. However, the mechanisms underlying T cell-mediated progressive muscle destruction in IIM remain to be elucidated. We here determined the involvement of the NKG2D - IL-15 signaling pathway. Primary human myoblasts expressed NKG2D ligands, which were further upregulated upon inflammatory stimuli. In parallel, shedding of the soluble NKG2D ligand MICA (sMICA) decreased upon inflammation potentially diminishing inhibition of NKG2D signaling. Membrane-related expression of IL-15 by myoblasts induced differentiation of naïve CD8+ T cells into highly activated, cytotoxic CD8+NKG2Dhigh T cells demonstrating NKG2D-dependent lysis of myoblasts in vitro. CD8+NKG2Dhigh T cell frequencies were increased in the peripheral blood of polymyositis (PM) patients and correlated with serum creatinine kinase concentrations, while serum sMICA levels were not significantly changed. In muscle biopsy specimens from PM patients expression of the NKG2D ligand MICA/B was upregulated, IL-15 was expressed by muscle cells, CD68+ macrophages as well as CD4+ T cells, and CD8+NKG2D+ cells were frequently detected within inflammatory infiltrates arguing for a local signaling circuit in the inflammatory muscle milieu. In conclusion, the NKG2D - IL-15 signaling pathway contributes to progressive muscle destruction in IIM potentially opening new therapeutic avenues. PMID:26646698

  6. Dietary fatty acid effects on T-cell-mediated immunity in mice infected with mycoplasma pulmonis or given carcinogens by injection.

    PubMed Central

    Bennett, M.; Uauy, R.; Grundy, S. M.

    1987-01-01

    To test whether or not diets enriched in w-6 polyunsaturated fatty acids are significantly immunosuppressive, B10.D2, DBA/2, and C3B6F1 mice were fed diets enriched for fatty acids: linoleic (POLY), oleic (MONO), palmitic (SAT), or eicosapentanoic (FISH). The B10.D2 and DBA/2 mice were given injected methylcholanthrene several weeks later, and immune studies were performed several months after carcinogen treatment. In conventional quarters, DBA/2 fed the POLY diet survived poorly, and many were infected with Mycoplasma pulmonis, even if given the vehicle, tractinoin, only. B10.D2 mice survived well unless on the POLY diet and given methylcholanthrene. Nevertheless, only mice on the POLY diet were significantly immunosuppressed, and only T-cell-mediated cutaneous sensitivity reactions were affected. Antibody, natural killer cell, and natural cytotoxic cell responses were not influenced by the diets. The C3B6F1 mice were assessed for immune functions prior to carcinogen (ethylnitrosourea) instillation into the trachea, and no immunosuppression was detected. After instillation, mice on the POLY and MONO diets were suppressed for T-cell cutaneous responses. Deliberate infection with Mycoplasma pulmonis resulted in suppressed cutaneous T-cell responses in the POLY group of C3B6F1 mice, and aspirin partially reversed the immunosuppression. Mice on the FISH diet were resistant to immunosuppression. It is tentatively concluded that diets rich in w-6 polyunsaturated diets, while not directly immunosuppressive, do predispose animals to suppression of certain T-cell-mediated immune responses. This immunosuppression can be "triggered" by infection and/or by exposure to carcinogens. PMID:3812635

  7. Challenges and Opportunities for T-Cell-Mediated Strategies to Eliminate HIV Reservoirs

    PubMed Central

    Brockman, Mark A.; Jones, R. Brad; Brumme, Zabrina L.

    2015-01-01

    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 toward appropriate viral antigens following latency. PMID:26483795

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

    PubMed

    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. PMID:9421323

  9. Effect of disodium cromoglycate on mast cell-mediated immediate-type allergic reactions.

    PubMed

    Shin, Hye-Young; Kim, Jung-Sook; An, Nyeon-Hyoung; Park, Rae-Kil; Kim, Hyung-Min

    2004-04-23

    We investigated the effect of disodium cromoglycate (DSCG) on mast cell-mediated immediate-type hypersensitivity. DSCG inhibited systemic allergic reaction induced by compound 48/80 dose-dependently. Passive cutaneous anaphylaxis was inhibited by 71.6% by oral administration of DSCG (1 g/kg). When DSCG was pretreated at concentration rang from 0.01-1000 g/kg, the serum histamine levels were reduced in a dose dependent manner. DSCG also significantly inhibited histamine release from rat peritoneal mast cell (RPMC) by compound 48/80. We confirmed that DSCG inhibited compound 48/80-induced degranulation of RPMC by alcian blue/nuclear fast red staining. In addition, DSCG showed a significant inhibitory effect on anti-dinitrophenyl IgE-mediated tumor necrosis factor-alpha production. These results indicate that DSCG inhibits mast cell-mediated immediate-type allergic reaction. PMID:15050425

  10. [Production of a dialysable transfer factor of cell mediated immunity by lymphoblastoid cells in continuous proliferation].

    PubMed

    Goust, J M; Viza, D; Moulias, R; Trejdosiewicz, L; Lesourd, B; Marescot, M R; Prévot, A

    1975-01-20

    Four lymphoblastoid cell lines tested in this work contain normally a dialysable moiety having by ultraviolet spectroscopy, column chromatography (Biogel P 10) and chemically the same properties than human dialysable Transfer Factor (TFd), but unable to transfer cell mediated immune response against common antigens. Two of them are able to do so after incubation with minimal amounts of TFd. Production of a molecule identical to human TFd is possible in some lymphoblastoid cell lines after induction with TFd. PMID:808340

  11. Loss of PTEN promotes resistance to T cell-mediated immunotherapy

    PubMed Central

    Peng, Weiyi; Chen, Jie Qing; Liu, Chengwen; Malu, Shruti; Creasy, Caitlin; Tetzlaff, Michael T; Xu, Chunyu; McKenzie, Jodi A; Zhang, Chunlei; Liang, Xiaoxuan; Williams, Leila J; Deng, Wanleng; Chen, Guo; Mbofung, Rina; Lazar, Alexander J; Torres-Cabala, Carlos A; Cooper, Zachary A; Chen, Pei-Ling; Tieu, Trang N; Spranger, Stefani; Yu, Xiaoxing; Bernatchez, Chantale; Forget, Marie-Andree; Haymaker, Cara; Amaria, Rodabe; McQuade, Jennifer L; Glitza, Isabella C; Cascone, Tina; Li, Haiyan S; Kwong, Lawrence N; Heffernan, Timothy P; Hu, Jianhua; Bassett, Roland L; Bosenberg, Marcus W; Woodman, Scott E; Overwijk, Willem W; Lizée, Gregory; Roszik, Jason; Gajewski, Thomas F; Wargo, Jennifer A; Gershenwald, Jeffrey E; Radvanyi, Laszlo; Davies, Michael A; Hwu, Patrick

    2015-01-01

    T cell-mediated immunotherapies are promising cancer treatments. However, most patients still fail to respond to these therapies. The molecular determinants of immune resistance are poorly understood. We show that loss of PTEN in tumor cells in preclinical models of melanoma inhibits T cell-mediated tumor killing and decreases T cell trafficking into tumors. In patients, PTEN loss correlates with decreased T cell infiltration at tumor sites, reduced likelihood of successful T cell expansion from resected tumors, and inferior outcomes with PD-1 inhibitor therapy. PTEN loss in tumor cells increased the expression of immunosuppressive cytokines, resulting in decreased T cell infiltration in tumors, and inhibited autophagy, which decreased T cell-mediated cell death. Treatment with a selective PI3Kβ inhibitor improved the efficacy of both anti-PD-1 and anti-CTLA4 antibodies in murine models. Together these findings demonstrate that PTEN loss promotes immune resistance and support the rationale to explore combinations of immunotherapies and PI3K-AKT pathway inhibitors. PMID:26645196

  12. Activation of cell-mediated immunity by Morinda citrifolia fruit extract and its constituents.

    PubMed

    Murata, Kazuya; Abe, Yumi; Futamura-Masudaa, Megumi; Uwaya, Akemi; Isami, Fumiyuki; Matsuda, Hideaki

    2014-04-01

    Morinda citrifolia, commonly known as noni, is a traditional natural medicine in French Polynesia and Hawaii. Functional foods derived from M. citrifolia fruit have been marketed to help prevent diseases and promote good health. The objective of this study was to assess the effects of M. citrifolia fruit on cell-mediated immunity. In the picryl chloride-induced contact dermatitis test, M. citrifolia fruit extract (Noni-ext) inhibited the suppression of cell-mediated immunity by immunosuppressive substances isolated from freeze-dried ascites of Ehrlich carcinoma-bearing mice (EC-sup). In addition, Noni-ext inhibited reduction of IL-2 production in EC-sup-treated mice and activated natural killer cells in normal mice. These results suggest that Noni-ext has multiple effects on the recovery of cell-mediated immunity. Furthermore, we investigated the active principles of Noni-ext and identified an iridoid glycoside, deacetylasperulosidic acid. Oral administration of deacetylasperulosidic acid inhibited the reduction of ear swelling, and also cancelled the suppression of IL-2 production along with the activation of natural killer cells in the same manner as that of Noni-ext. PMID:24868850

  13. Nonspecific cytotoxic cells of teleosts are armed with multiple granzymes and other components of the granule exocytosis pathway.

    PubMed

    Praveen, Kesavannair; Leary, John H; Evans, Donald L; Jaso-Friedmann, Liliana

    2006-03-01

    Granzymes are members of the serine protease family and major components of cytotoxic granules of professional killer cells. Multiple granzymes have been identified from human and rodents with different substrate specificities. Although the significance of granzymes A and B in cell-mediated cytotoxicity has been extensively investigated, recent reports suggest that other granzymes may have either equal or greater importance in mediating cell death. Studies on the evolution of these closely related proteases were hindered by the lack of sequence and biochemical information of granzymes from "lower vertebrates." Here we report the generation of a catalytically active recombinant granzyme identified in the cytotoxic cells of an ectothermic vertebrate. Fully active, soluble recombinant catfish granzyme-1 (CFGR-1) was generated using a yeast-based expression system. In vitro enzyme kinetic assays using various thiobenzyl ester substrates verified its tryptase activity in full agreement with previous observations by sequence comparison and molecular modeling. The tryptase activity that was secreted from catfish NCC during an in vitro cytotoxicity assay strongly correlated with the cytotoxicity induced by these cells. Evidence for additional granzymes with different substrate specificities in NCC was obtained by analysis of the protease activity of supernatants collected from in vitro cytotoxicity assays. Searches of the catfish EST database further confirmed the presence of teleost granzymes with different substrate specificities. Granzyme activity measurements suggested a predominance of chymase and tryptase activities in NCC. Further proof that the granule exocytosis pathway is one of the cytotoxic mechanisms in NCC was provided by the expression of granule components perforin, granulysin and serglycin detected by RT-PCR analysis. These results demonstrate the evidence for a parallel evolution of effector molecules of cell-mediated cytotoxicity in teleosts. PMID

  14. Enhancing natural killer cell-mediated lysis of lymphoma cells by combining therapeutic antibodies with CD20-specific immunoligands engaging NKG2D or NKp30

    PubMed Central

    Kellner, Christian; Günther, Andreas; Humpe, Andreas; Repp, Roland; Klausz, Katja; Derer, Stefanie; Valerius, Thomas; Ritgen, Matthias; Brüggemann, Monika; van de Winkel, Jan GJ; Parren, Paul WHI; Kneba, Michael; Gramatzki, Martin; Peipp, Matthias

    2016-01-01

    Antibody-dependent cell-mediated cytotoxicity (ADCC) mediated through the IgG Fc receptor FcγRIIIa represents a major effector function of many therapeutic antibodies. In an attempt to further enhance natural killer (NK) cell-mediated ADCC, we combined therapeutic antibodies against CD20 and CD38 with recombinant immunoligands against the stimulatory NK cell receptors NKG2D or NKp30. These immunoligands, respectively designated as ULBP2:7D8 and B7-H6:7D8, contained the CD20 scFv 7D8 as a targeting moiety and a cognate ligand for either NKG2D or NKp30 (i.e. ULBP2 and B7-H6, respectively). Both the immunoligands synergistically augmented ADCC in combination with the CD20 antibody rituximab and the CD38 antibody daratumumab. Combinations with ULBP2:7D8 resulted in higher cytotoxicity compared to combinations with B7-H6:7D8, suggesting that coligation of FcγRIIIa with NKG2D triggered NK cells more efficiently than with NKp30. Addition of B7-H6:7D8 to ULBP2:7D8 and rituximab in a triple combination did not further increase the extent of tumor cell lysis. Importantly, immunoligand-mediated enhancement of ADCC was also observed for tumor cells and autologous NK cells from patients with hematologic malignancies, in which, again, ULBP2:7D8 was particularly active. In summary, co-targeting of NKG2D was more effective in promoting rituximab or daratumumab-mediated ADCC by NK cells than co-ligation of NKp30. The observed increase in the ADCC activity of these therapeutic antibodies suggests promise for a ‘dual-dual-targeting’ approach in which tumor cell surface antigens are targeted in concert with two distinct activating NK cell receptors (i.e. FcγRIIIa and NKG2D or B7-H6). PMID:26942070

  15. Membrane-Bound TRAIL Supplements Natural Killer Cell Cytotoxicity Against Neuroblastoma Cells

    PubMed Central

    Sheard, Michael A.; Asgharzadeh, Shahab; Liu, Yin; Lin, Tsen-Yin; Wu, Hong-Wei; Ji, Lingyun; Groshen, Susan; Lee, Dean A.; Seeger, Robert C.

    2013-01-01

    Neuroblastoma cells have been reported to be resistant to death induced by soluble, recombinant forms of TRAIL (CD253/TNFSF10) due to low or absent expression of caspase-8 and/or TRAIL-receptor 2 (TRAIL-R2/DR5/CD262/TNFRSF10b). However, their sensitivity to membrane-bound TRAIL on natural killer (NK) cells is not known. Comparing microarray gene expression and response to NK cell-mediated cytotoxicity, we observed a correlation between TRAIL-R2 expression and the sensitivity of fourteen neuroblastoma cell lines to the cytotoxicity of NK cells activated with IL-2 plus IL-15. Even though most NK cytotoxicity was dependent upon perforin, the cytotoxicity was supplemented by TRAIL in fourteen of seventeen (82%) neuroblastoma cell lines as demonstrated using an anti-TRAIL neutralizing antibody. Similarly, a recently developed NK cell expansion system employing IL-2 plus lethally irradiated K562 feeder cells constitutively expressing membrane-bound IL-21 (K562 clone 9.mbIL21) resulted in activated NK cells derived from normal healthy donors and neuroblastoma patients that also utilized TRAIL to supplement cytotoxicity. Exogenous IFNγ up-regulated expression of caspase-8 in three of four neuroblastoma cell lines and increased the contribution of TRAIL to NK cytotoxicity against two of the three lines; however, relatively little inhibition of cytotoxicity was observed when activated NK cells were treated with an anti-IFNγ neutralizing antibody. Constraining the binding of anti-TRAIL neutralizing antibody to membrane-bound TRAIL but not soluble TRAIL indicated that membrane-bound TRAIL alone was responsible for essentially all of the supplemental cytotoxicity. Together, these findings support a role for membrane-bound TRAIL in the cytotoxicity of NK cells against neuroblastoma cells. PMID:23719242

  16. The Exonuclease Domain of Lassa Virus Nucleoprotein Is Involved in Antigen-Presenting-Cell-Mediated NK Cell Responses

    PubMed Central

    Russier, Marion; Reynard, Stéphanie; Carnec, Xavier

    2014-01-01

    ABSTRACT Lassa virus is an Old World Arenavirus which causes Lassa hemorrhagic fever in humans, mostly in West Africa. Lassa fever is an important public health problem, and a safe and effective vaccine is urgently needed. The infection causes immunosuppression, probably due to the absence of activation of antigen-presenting cells (dendritic cells and macrophages), low type I interferon (IFN) production, and deficient NK cell function. However, a recombinant Lassa virus carrying D389A and G392A substitutions in the nucleoprotein that abolish the exonuclease activity and IFN activation loses its inhibitory activity and induces strong type I IFN production by dendritic cells and macrophages. We show here that during infection by this mutant Lassa virus, antigen-presenting cells trigger efficient human NK cell responses in vitro, including production of IFN-γ and cytotoxicity. NK cell activation involves close contact with both antigen-presenting cells and soluble factors. We report that infected dendritic cells and macrophages express the NKG2D ligands major histocompatibility complex (MHC) class I-related chains A and B and that they may produce interleukin-12 (IL-12), IL-15, and IL-18, all involved in NK cell functions. NK cell degranulation is significantly increased in cocultures, suggesting that NK cells seem to kill infected dendritic cells and macrophages. This work confirms the inhibitory function of Lassa virus nucleoprotein. Importantly, we demonstrate for the first time that Lassa virus nucleoprotein is involved in the inhibition of antigen-presenting cell-mediated NK cell responses. IMPORTANCE The pathogenesis and immune responses induced by Lassa virus are poorly known. Recently, an exonuclease domain contained in the viral nucleoprotein has been shown to be able to inhibit the type I IFN response by avoiding the recognition of viral RNA by cell sensors. Here, we studied the responses of NK cells to dendritic cells and macrophages infected with a

  17. Dehydroeffusol effectively inhibits human gastric cancer cell-mediated vasculogenic mimicry with low toxicity

    SciTech Connect

    Liu, Wenming; Meng, Mei; Zhang, Bin; Du, Longsheng; Pan, Yanyan; Yang, Ping; Gu, Zhenlun; Zhou, Quansheng Cao, Zhifei

    2015-09-01

    Accumulated data has shown that various vasculogenic tumor cells, including gastric cancer cells, are able to directly form tumor blood vessels via vasculogenic mimicry, supplying oxygen and nutrients to tumors, and facilitating progression and metastasis of malignant tumors. Therefore, tumor vasculogenic mimicry is a rational target for developing novel anticancer therapeutics. However, effective antitumor vasculogenic mimicry-targeting drugs are not clinically available. In this study, we purified 2,7-dihydroxyl-1-methyl-5-vinyl-phenanthrene, termed dehydroeffusol, from the traditional Chinese medicinal herb Juncus effusus L., and found that dehydroeffusol effectively inhibited gastric cancer cell-mediated vasculogenic mimicry in vitro and in vivo with very low toxicity. Dehydroeffusol significantly suppressed gastric cancer cell adhesion, migration, and invasion. Molecular mechanistic studies revealed that dehydroeffusol markedly inhibited the expression of a vasculogenic mimicry master gene VE-cadherin and reduced adherent protein exposure on the cell surface by inhibiting gene promoter activity. In addition, dehydroeffusol significantly decreased the expression of a key vasculogenic gene matrix metalloproteinase 2 (MMP2) in gastric cancer cells, and diminished MMP2 protease activity. Together, our results showed that dehydroeffusol effectively inhibited gastric cancer cell-mediated vasculogenic mimicry with very low toxicity, suggesting that dehydroeffusol is a potential drug candidate for anti-gastric cancer neovascularization and anti-gastric cancer therapy. - Highlights: • Dehydroeffusol markedly inhibits gastric cancer cell-mediated vasculogenic mimicry. • Dehydroeffusol suppresses the expression of vasculogenic mimicry key gene VE-cadherin. • Dehydroeffusol decreases the MMP2 expression and activity in gastric cancer cells. • Dehydroeffusol is a potential anti-cancer drug candidate with very low toxicity.

  18. Ornamental comb colour predicts T-cell-mediated immunity in male red grouse Lagopus lagopus scoticus

    NASA Astrophysics Data System (ADS)

    Mougeot, Francois

    2008-02-01

    Sexual ornaments might reliably indicate the ability to cope with parasites and diseases, and a better ability to mount a primary inflammatory response to a novel challenge. Carotenoid-based ornaments are amongst the commonest sexual signals of birds and often influence mate choice. Because carotenoids are immuno-stimulants, signallers may trade-off allocating these to ornamental colouration or using them for immune responses, so carotenoid-based ornaments might be particularly useful as honest indicators of immuno-compentence. Tetraonid birds, such as the red grouse Lagopus lagopus scoticus, exhibit supra-orbital yellow red combs, a conspicuous ornament which functions in intra- and inter-sexual selection. The colour of combs is due to epidermal pigmentation by carotenoids, while their size is testosterone-dependent. In this study, I investigated whether comb characteristics, and in particular, comb colour, indicated immuno-competence in free-living male red grouse. I assessed T-cell-mediated immunity using a standardised challenge with phytohaemagglutinin. Red grouse combs reflect in the red and in the ultraviolet spectrum of light, which is not visible to humans but that grouse most likely see, so I measured comb colour across the whole bird visible spectrum (300 700 nm) using a reflectance spectrometer. I found that males with bigger and redder combs, but with less ultraviolet reflectance, had greater T-cell-mediated immune response. Comb colour predicted T-cell-mediated immune response better than comb size, indicating that the carotenoid-based colouration of this ornament might reliably signal this aspect of male quality.

  19. Essential oil of clove (Eugenia caryophyllata) augments the humoral immune response but decreases cell mediated immunity.

    PubMed

    Halder, Sumita; Mehta, Ashish K; Mediratta, Pramod K; Sharma, Krishna K

    2011-08-01

    The present study was undertaken to explore the effect of the essential oil isolated from the buds of Eugenia caryophyllata on some immunological parameters. Humoral immunity was assessed by measuring the hemagglutination titre to sheep red blood cells and delayed type hypersensitivity was assessed by measuring foot pad thickness. Clove oil administration produced a significant increase in the primary as well as secondary humoral immune response. In addition, it also produced a significant decrease in foot pad thickness compared with the control group. Thus, these results suggest that clove oil can modulate the immune response by augmenting humoral immunity and decreasing cell mediated immunity. PMID:21796701

  20. HLA Associations and Clinical Implications in T-Cell Mediated Drug Hypersensitivity Reactions: An Updated Review

    PubMed Central

    Cheng, Chi-Yuan; Chen, Chi-Hua; Chen, Wei-Li; Deng, Shin-Tarng; Chung, Wen-Hung

    2014-01-01

    T-cell mediated drug hypersensitivity reactions may range from mild rash to severe fatal reactions. Among them, drug reaction with eosinophilia and systemic symptoms (DRESS) or drug-induced hypersensitivity syndrome (DIHS), Stevens-Johnson syndrome/ toxic epidermal necrolysis (SJS/TEN), are some of the most life-threatening severe cutaneous adverse reactions (SCARs). Recent advances in pharmacogenetic studies show strong genetic associations between human leukocyte antigen (HLA) alleles and susceptibility to drug hypersensitivity. This review summarizes the literature on recent progresses in pharmacogenetic studies and clinical application of pharmacogenetic screening based on associations between SCARs and specific HLA alleles to avoid serious conditions associated with drug hypersensitivity. PMID:24901010

  1. Determination of Cytotoxicity.

    PubMed

    2016-01-01

    Cytotoxicity assays are used for drug screening and cytotoxicity tests of chemicals. Nowadays, various reagents are used for cell viability detection. They are based on various cell functions such as enzyme activity, cell membrane permeability, cell adherence, ATP production, co-enzyme production and nucleotide uptake activity. Many have established methods such as colony formation method, crystal violet method, tritium-labelled thymidine uptake method, MTT and WST methods, which are used for counting the number of live cells. Moreover, trypan blue is a widely used assay for staining dead cells. In this method, cell viability must be determined by counting the unstained cells with a microscope or other instruments. This chapter is a collection of all these methods to be followed by researchers in a sequential manner. PMID:26939283

  2. Cytotoxicity of Vinca minor.

    PubMed

    Khanavi, Mahnaz; Pourmoslemi, Shabnam; Farahanikia, Behnaz; Hadjiakhoondi, Abbas; Ostad, Seyed Nasser

    2010-01-01

    Vinca minor L. (Apocynaceae) is a medicinal plant that has long been used to treat cerebral and memory disorders in European folk medicine. Furthermore, it contains more than 50 alkaloids, some of them having bisindole structure such as the antineoplastic alkaloids present in Catharanthus roseus (L.) G. Don (Apocynaceae). In this study, the plant's alkaloid extract was divided into three fractions and the cytotoxic effects on cell proliferation of HT-29, Caco-2, T47D, and NIH/3T3 cell lines were examined. All alkaloid fractions showed a dose-dependent cytotoxic effect on the cell lines. IC(50) values confirmed that the growth and proliferation of NIH/3T3 cells were less affected in comparison to other cell lines. PMID:20645762

  3. Fluorinated Nanocarbons Cytotoxicity.

    PubMed

    Teo, Wei Zhe; Chua, Chun Kiang; Sofer, Zdenek; Pumera, Martin

    2015-09-01

    As the research in nanotechnology progresses, there will eventually be an influx in the number of commercial products containing different types of nanomaterials. This phenomenon might damage our health and environment if the nanomaterials used are found to be toxic and they are released into the waters when the products degrade. In this study, we investigated the cytotoxicity of fluorinated nanocarbons (CXFs), a group of nanomaterials which can find applications in solid lubricants and lithium primary batteries. Our cell viability findings indicated that the toxicological effects induced by the CXF are dependent on the dose, size, shape, and fluorine content of the CXF. In addition, we verified that CXFs have insignificant interactions with the cell viability assays-methylthiazolyldiphenyl-tetrazolium bromide (MTT) and water-soluble tetrazolium salt (WST-8), thus suggesting that the cytotoxicity data obtained are unlikely to be affected by CXF-induced artifacts and the results will be reliable. PMID:26215131

  4. Humoral, Mucosal, and Cell-Mediated Immunity Against Vaccine and Nonvaccine Genotypes After Administration of Quadrivalent Human Papillomavirus Vaccine to HIV-Infected Children

    PubMed Central

    Weinberg, Adriana; Song, Lin-Ye; Saah, Alfred; Brown, Martha; Moscicki, Anna B.; Meyer, William A.; Bryan, Janine; Levin, Myron J.

    2012-01-01

    Objectives. To characterize the immunogenicity of a quadrivalent human papillomavirus vaccine (QHPV) in human immunodeficiency virus (HIV)–infected children, we studied their immune responses to 3 or 4 doses. Methods. HIV-infected children aged 7–12 years with a CD4 cell percentage of ≥15% of lymphocytes, received 3 doses of QHPV with or without a fourth dose after 72 weeks. Type-specific and cross-reactive antibodies and cell-mediated immunity were measured. Results. Type-specific antibodies to HPV6, 11, and 16 were detected in 100% and ≥94% of children at 4 and 72 weeks, respectively, after the third QHPV dose. Corresponding numbers for HPV18 were 97% and 76%, respectively. A fourth QHPV dose increased seropositivity to ≥96% for all vaccine genotypes. Four weeks after the third QHPV dose, 67% of vaccinees seroconverted to HPV31, an HPV16-related genotype not in the vaccine; 69% and 39% of vaccinees developed mucosal HPV16 and 18 immunoglobulin G antibodies, respectively; and 60% and 52% of vaccinees developed cytotoxic T lymphocytes (CTLs) for HPV16 and 31, respectively. Conclusions. Three QHPV doses generated robust and persistent antibodies to HPV6, 11, and 16 but comparatively weaker responses to HPV18. A fourth dose increased antibodies against all vaccine genotypes in an anamnestic fashion. CTLs and mucosal antibodies against vaccine genotypes, as well as cross-reactive antibodies and CTL against nonvaccine genotypes, were detected. PMID:22859825

  5. Induction of ATM/ATR pathway combined with Vγ2Vδ2 T cells enhance cytotoxicity of ovarian cancer cells

    PubMed Central

    Lu, Jingwei; Das, Manjusri; Kanji, Suman; Aggarwal, Reeva; Joseph, Matthew; Ray, Alo; Shapiro, Charles L.; Pompili, Vincent J.; Das, Hiranmoy

    2014-01-01

    Summary Many ovarian cancer cells express stress-related molecule MICA/B on their surface that is recognized by Vγ2Vδ2 T cells through their NKG2D receptor, which is transmitted to downstream stress-signaling pathway. However, it is yet to be established how Vγ2Vδ2 T cells-mediated recognition of MICA/B signal is transmitted to downstream stress-related molecules. Identifying targeted molecules would be critical to develop a better therapy for ovarian cancer cells. It is well established that ATM/ATR signal transduction pathways, which is modulated by DNA damage, replication stress, and oxidative stress play central role in stress signaling pathway regulating cell cycle checkpoint and apoptosis. We investigated whether ATM/ATR and its down stream molecules affect Vγ2Vδ2 T cells-mediated cytotoxicity. Herein, we show that ATM/ATR pathway is modulated in ovarian cancer cells in presence of Vγ2Vδ2 T cells. Furthermore, downregulation of ATM pathway resulted downregulation of MICA, and reduced Vγ2Vδ2 T cells-mediated cytotoxicity. Alternately, stimulating ATM pathway enhanced expression of MICA, and sensitized ovarian cancer cells for cytotoxic lysis by Vγ2Vδ2 T cells. We further show that combining currently approved chemotherapeutic drugs, which induced ATM signal transduction, along with Vγ2Vδ2 T cells enhanced cytotoxicity of resistant ovarian cancer cells. These findings indicate that ATM/ATR pathway plays an important role in tumor recognition, and drugs promoting ATM signaling pathway might be considered as a combination therapy together with Vγ2Vδ2 T cells for effectively treating resistant ovarian cancer cells. PMID:24726882

  6. Tetherin promotes the innate and adaptive cell-mediated immune response against retrovirus infection in vivo

    PubMed Central

    Li, Sam X.; Barrett, Bradley S.; Heilman, Karl J.; Messer, Ronald J.; Liberatore, Rachel A.; Bieniasz, Paul D.; Kassiotis, George; Hasenkrug, Kim J.; Santiago, Mario L.

    2014-01-01

    Tetherin/BST-2 is a host restriction factor that could directly inhibit retroviral particle release by tethering nascent virions to the plasma membrane. However, the immunological impact of Tetherin during retrovirus infection remains unknown. We now show that Tetherin influences antiretroviral cell-mediated immune responses. In contrast to the direct antiviral effects of Tetherin, which are dependent on cell surface expression, the immunomodulatory effects are linked to the endocytosis of the molecule. Mice encoding endocytosis-competent C57BL/6 Tetherin exhibited lower viremia and pathology at 7 days post-infection with Friend retrovirus (FV) compared to mice encoding endocytosis-defective NZW/LacJ Tetherin. Notably, antiretroviral protection correlated with stronger NK cell responses. In addition, FV infection levels were significantly lower in wild-type C57BL/6 mice than in Tetherin knock-out mice at 2 weeks post-infection, and antiretroviral protection correlated with stronger NK cell and virus-specific CD8+ T cell responses. The results demonstrate that Tetherin acts as a modulator of the cell-mediated immune response against retrovirus infection in vivo. PMID:24872193

  7. Design strategies and applications of circulating cell-mediated drug delivery systems

    PubMed Central

    Kim, Gloria B.; Dong, Cheng; Yang, Jian

    2015-01-01

    Drug delivery systems, particularly nanomaterial-based drug delivery systems, possess a tremendous amount of potential to improve diagnostic and therapeutic effects of drugs. Controlled drug delivery targeted to a specific disease is designed to significantly improve the pharmaceutical effects of drugs and reduce their side effects. Unfortunately, only a few targeted drug delivery systems can achieve high targeting efficiency after intravenous injection, even with the development of numerous surface markers and targeting modalities. Thus, alternative drug and nanomedicine targeting approaches are desired. Circulating cells, such as erythrocytes, leukocytes, and stem cells, present innate disease sensing and homing properties. Hence, using living cells as drug delivery carriers has gained increasing interest in recent years. This review highlights the recent advances in the design of cell-mediated drug delivery systems and targeting mechanisms. The approaches of drug encapsulation/conjugation to cell-carriers, cell-mediated targeting mechanisms, and the methods of controlled drug release are elaborated here. Cell-based “live” targeting and delivery could be used to facilitate a more specific, robust, and smart payload distribution for the next-generation drug delivery systems. PMID:25984572

  8. Cordyceps militaris Enhances Cell-Mediated Immunity in Healthy Korean Men.

    PubMed

    Kang, Ho Joon; Baik, Hyun Wook; Kim, Sang Jung; Lee, Seong Gyu; Ahn, Hong Yup; Park, Ju Sang; Park, Sang Jong; Jang, Eun Jeong; Park, Sang Woon; Choi, Jin Young; Sung, Ji Hee; Lee, Seung Min

    2015-10-01

    Cordyceps militaris is a mushroom traditionally used for diverse pharmaceutical purposes in East Asia, including China, and has been found to be effective for enhancing immunity through various types of animal testing. The aim of this study is to determine the efficacy of C. militaris for enhancing cell-mediated immunity and its safety in healthy male adults. Healthy male adults were divided into the experimental group (n = 39), given 1.5 g/day of ethanol treated C. militaris in capsules, and the control group (n = 40), given the same number of identical placebo capsules filled with microcrystalline cellulose and lactose for 4 weeks from February 13 to March 14, 2012; the natural killer (NK) cell activity, lymphocyte proliferation index (PI), and T-helper cell 1 (Th1) cytokine cluster (interferon [IFN]-γ, interleukin [IL]-12, IL-2, and tumor necrosis factor [TNF]-α) were measured, along with stability test, at weeks 0, 2, and 4. The C. militaris group showed a statistically significant greater increase in NK200 (P = .0010), lymphocyte PI (P ≤ .0001), IL-2 (P = .0096), and IFN-γ (P = .0126), compared with the basal level, than the placebo group. There was no statistically significant adverse reaction. C. militaris enhanced the NK cell activity and lymphocyte proliferation and partially increased Th1 cytokine secretion. Therefore, C. militaris is safe and effective for enhancing cell-mediated immunity of healthy male adults. PMID:26284906

  9. Inhibition of humoral and cell-mediated immune responses in man by distinct suppressor cell systems.

    PubMed Central

    Lobo, P I; Spencer, C E

    1979-01-01

    Studies were designed to investigate whether the suppressor cell systems that regulate the humoral and cell-mediated immune responses belong to the same subsets of T cells or different subsets. Mitogen-activated suppressor cells were simultaneously assayed for their ability to inhibit (a) pokeweed mitogen-induced generation of plasma cells, (b) blastogenic response of lymphocytes to allogeneic cells, and (c) generation of killer cells in the cell-mediated lymphocytotoxicity assay. We found that suppressor cells that inhibited the generation of plasma cells were activated by concanavalin A (Con A) and were both radiation and prednisone sensitive. Suppressors that inhibited the blastogenic response in lymphocytes to allogenic cells were also activated by Con A but differed in that they were both radiation and prednisone resistant. In contrast, suppressors that inhibited the generation of the killer cells were activated with phytohemagglutinin and not Con A. These suppressors were prednisone and radiation resistant. These observations cannot be explained by differences at the pro-suppressor or suppressor activator levels as both T cell subsets are radiosensitive. Alternatively, heterogeneity of suppressor cell systems may explain these differences. PMID:156197

  10. Ripe fruit of Rubus coreanus inhibits mast cell-mediated allergic inflammation.

    PubMed

    Kim, Hui-Hun; Choi, Phil Hyung; Yoo, Jin-Su; Jeon, Hoon; Chae, Byeong-Suk; Park, Jeong-Suk; Kim, Sang-Hyun; Shin, Tae-Yong

    2012-02-01

    In this study, we investigated the effect of a water extract of the ripe fruits of Rubus coreanus Miq. (Rosaceae) (RFRC) on mast cell-mediated allergic inflammation and studied the possible mechanism of action. Mast cell-mediated allergic disease is involved in many diseases such as anaphylaxis, rhinitis, asthma and atopic dermatitis. RFRC dose-dependently inhibited compound 48/80-induced systemic anaphylaxis and serum histamine release in mice. RFRC reduced the immunoglobulin E (IgE)-mediated local allergic reaction, passive cutaneous anaphylaxis. RFRC attenuated histamine release from rat peritoneal mast cells and human mast cells by the reduction of intracellular calcium. RFRC decreased the phorbol 12-myristate 13-acetate (PMA) and the calcium ionophore A23187 (PMACI)-stimulated expression and secretion of pro-inflammatory cytokines in human mast cells. The inhibitory effect of RFRC on cytokine production was nuclear factor (NF)-κB- and mitogen-activated protein kinase (MAPK)-dependent. In addition, RFRC suppressed the activation of caspase-1. Our findings provide evidence that RFRC inhibits mast cell-derived allergic inflammatory reactions, and for the involvement of calcium, NF-κB, MAPKs and caspase-1 in these effects. Furthermore, in vivo and in vitro anti-allergic inflammatory effects of RFRC provide affirmative proof of a possible therapeutic application of this agent in allergic inflammatory diseases. PMID:22075758

  11. Interleukin 2-diphtheria toxin fusion protein can abolish cell-mediated immunity in vivo.

    PubMed Central

    Kelley, V E; Bacha, P; Pankewycz, O; Nichols, J C; Murphy, J R; Strom, T B

    1988-01-01

    De novo expression of the interleukin 2 receptor (IL-2R) is a critical and pivotal event in initiation of an immune response. Targeting the low-affinity IL-2-binding p55 subunit of the high-affinity IL-2R with the rat anti-mouse IgM monoclonal antibody M7/20 suppresses a variety of T-cell-mediated reactions, including transplant rejection, autoimmunity, and delayed-type hypersensitivity (DTH). A hybrid IL-2-toxin gene was constructed from the diphtheria toxin gene by replacing the DNA encoding the diphtheria toxin receptor-binding domain with the DNA encoding the receptor-binding domain of IL-2, and the fusion protein encoded by the hybrid gene was expressed in Escherichia coli [Williams, D.P., Parker, K., Bacha, P., Bishai, W., Borowski, M., Genbauffe, F., Strom, T.B. & Murphy, J.R. (1987) Protein Eng. 1, 493-498]. We examined the action of the chimeric IL-2-toxin fusion protein on an in vivo T-cell mediated response, DTH. The IL-2-toxin fusion protein was found to be a potent immunosuppressive agent. Treatment of mice with the IL-2-toxin blocks DTH and prevents expansion of IL-2R+ T cells. Indeed, IL-2-toxin treatment targets IL-2R+ T cells in vivo and is shown to selectively eliminate their appearance in draining lymph nodes. DTH suppression was observed even in mice possessing high titers of antibodies to diphtheria toxoid. PMID:3131768

  12. Cutting edge: membrane lymphotoxin regulates CD8(+) T cell-mediated intestinal allograft rejection.

    PubMed

    Guo, Z; Wang, J; Meng, L; Wu, Q; Kim, O; Hart, J; He, G; Zhou, P; Thistlethwaite, J R; Alegre, M L; Fu, Y X; Newell, K A

    2001-11-01

    Blocking the CD28/B7 and/or CD154/CD40 costimulatory pathways promotes long-term allograft survival in many transplant models where CD4(+) T cells are necessary for rejection. When CD8(+) T cells are sufficient to mediate rejection, these approaches fail, resulting in costimulation blockade-resistant rejection. To address this problem we examined the role of lymphotoxin-related molecules in CD8(+) T cell-mediated rejection of murine intestinal allografts. Targeting membrane lymphotoxin by means of a fusion protein, mAb, or genetic mutation inhibited rejection of intestinal allografts by CD8(+) T cells. This effect was associated with decreased monokine induced by IFN-gamma (Mig) and secondary lymphoid chemokine (SLC) gene expression within allografts and spleens respectively. Blocking membrane lymphotoxin did not inhibit rejection mediated by CD4(+) T cells. Combining disruption of membrane lymphotoxin and treatment with CTLA4-Ig inhibited rejection in wild-type mice. These data demonstrate that membrane lymphotoxin is an important regulatory molecule for CD8(+) T cells mediating rejection and suggest a strategy to avoid costimulation blockade-resistant rejection. PMID:11673481

  13. Controlling Stem Cell-mediated Bone Regeneration through Tailored Mechanical Properties of Collagen Scaffolds

    PubMed Central

    Sun, Hongli; Zhu, Feng; Hu, Qingang; Krebsbach, Paul H.

    2014-01-01

    Mechanical properties of the extracellular matrix (ECM) play an essential role in cell fate determination. To study the role of mechanical properties of ECM in stem cell-mediated bone regeneration, we used a 3D in vivo ossicle model that recapitulates endochondral bone formation. Three-dimensional gelatin scaffolds with distinct stiffness were developed using 1-Ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC) mediated zero-length crosslinking. The mechanical strength of the scaffolds was significantly increased by EDC treatment, while the microstructure of the scaffold was preserved. Cell behavior on the scaffolds with different mechanical properties was evaluated in vitro and in vivo. EDC-treated scaffolds promoted early chondrogenic differentiation, while it promoted both chondrogenic and osteogenic differentiation at later time points. Both micro-computed tomography and histologic data demonstrated that EDC-treatment significantly increased trabecular bone formation by transplanted cells transduced with AdBMP. Moreover, significantly increased chondrogenesis was observed in the EDC-treated scaffolds. Based on both in vitro and in vivo data, we conclude that the high mechanical strength of 3D scaffolds promoted stem cell mediated bone regeneration by promoting endochondral ossification. These data suggest a new method for harnessing stem cells for bone regeneration in vivo by tailoring the mechanical properties of 3D scaffolds. PMID:24211076

  14. In vivo and in vitro effects of lead on humoral and cell-mediated immunity.

    PubMed Central

    Lawrence, D A

    1981-01-01

    The humoral and cell-mediated immune responses of murine lymphocytes exposed to lead in vivo and in vitro were investigated. In vivo Pb was administered via the drinking water (0 to 10 mM) for 1 to 10 weeks. In vivo exposure of the mice to Pb did not alter significantly their plaque-forming cell response to sheep erythrocytes; however, their susceptibility to Listeria infection was reduced significantly with Pb dosages of greater than 0.4 mM. Although the in vivo plaque-forming cell responses did not appear to be altered, in vitro assessment of the reactivity of these in vivo Pb-exposed lymphocytes indicated that intermediate doses enhanced, but a high dose (10 mM) was suppressive. The 10 mM in vivo Pb dose suppressed the in vitro plaque-forming cell response, the mixed-lymphocyte culture response, and lipopolysaccharide-induced proliferation, but it did not affect concanavalin A- or phytohemagglutinin-induced proliferation. Interestingly, in vitro Pb exposure (10(-6) to 10(-4) M) of murine spleen cells caused an enhancement of most activities even though these in vitro concentrations of Pb were slightly above the in vivo concentrations. Direct in vitro Pb effects on the lymphocytes could be measured, and Pb consistently enhanced humoral and cell-mediated immunity. PMID:6971260

  15. Dehydroeffusol effectively inhibits human gastric cancer cell-mediated vasculogenic mimicry with low toxicity.

    PubMed

    Liu, Wenming; Meng, Mei; Zhang, Bin; Du, Longsheng; Pan, Yanyan; Yang, Ping; Gu, Zhenlun; Zhou, Quansheng; Cao, Zhifei

    2015-09-01

    Accumulated data has shown that various vasculogenic tumor cells, including gastric cancer cells, are able to directly form tumor blood vessels via vasculogenic mimicry, supplying oxygen and nutrients to tumors, and facilitating progression and metastasis of malignant tumors. Therefore, tumor vasculogenic mimicry is a rational target for developing novel anticancer therapeutics. However, effective antitumor vasculogenic mimicry-targeting drugs are not clinically available. In this study, we purified 2,7-dihydroxyl-1-methyl-5-vinyl-phenanthrene, termed dehydroeffusol, from the traditional Chinese medicinal herb Juncus effusus L., and found that dehydroeffusol effectively inhibited gastric cancer cell-mediated vasculogenic mimicry in vitro and in vivo with very low toxicity. Dehydroeffusol significantly suppressed gastric cancer cell adhesion, migration, and invasion. Molecular mechanistic studies revealed that dehydroeffusol markedly inhibited the expression of a vasculogenic mimicry master gene VE-cadherin and reduced adherent protein exposure on the cell surface by inhibiting gene promoter activity. In addition, dehydroeffusol significantly decreased the expression of a key vasculogenic gene matrix metalloproteinase 2 (MMP2) in gastric cancer cells, and diminished MMP2 protease activity. Together, our results showed that dehydroeffusol effectively inhibited gastric cancer cell-mediated vasculogenic mimicry with very low toxicity, suggesting that dehydroeffusol is a potential drug candidate for anti-gastric cancer neovascularization and anti-gastric cancer therapy. PMID:25982451

  16. CD47 Blockade Triggers T cell-mediated Destruction of Immunogenic Tumors

    PubMed Central

    Liu, Xiaojuan; Pu, Yang; Cron, Kyle; Deng, Liufu; Kline, Justin; Frazier, William A.; Xu, Hairong; Peng, Hua; Fu, Yang-Xin; Xu, Meng Michelle

    2015-01-01

    Macrophage phagocytosis of tumor cells mediated by CD47-specific blocking antibodies has been proposed to be the major effector mechanism in xenograft models. Using syngeneic immunocompetent tumor models, we reveal that in the therapeutic effects of CD47 blockade depend on dendritic cell (DC) but not macrophage cross-priming of T cell responses in immunocompetent mice. The therapeutic effects of anti-CD47 antibody therapy were abrogated in T cell-deficient mice. In addition, the anti-tumor effects of CD47 blockade required expression of the cytosolic DNA sensor STING, but neither MyD88 nor TRIF, in CD11c+ cells, suggesting that cytosolic sensing of DNA from tumor cells is enhanced by anti-CD47 treatment, further bridging the innate and adaptive responses. Notably, the timing of administration of standard chemotherapy markedly impacted the induction of anti-tumor T cell responses by CD47 blockade. Together, our findings indicate that CD47 blockade drives T cell-mediated elimination of immunogenic tumors. PMID:26322579

  17. Skewed B cell differentiation affects lymphoid organogenesis but not T cell-mediated autoimmunity.

    PubMed

    Colombo, E; Tentorio, P; Musio, S; Rajewsky, K; Pedotti, R; Casola, S; Farina, C

    2014-04-01

    B cell receptor (BCR) signalling determines B cell differentiation and may potentially alter T cell-mediated immune responses. In this study we used two transgenic strains of BCR-deficient mice expressing Epstein-Barr virus latent membrane protein (LMP)2A in B cells, where either follicular and marginal zone differentiation (D(H)LMP2A mice) or B-1 cell development (V(H)LMP2A mice) were supported, and evaluated the effects of skewed B lymphocyte differentiation on lymphoid organogenesis and T cell responses in vivo. Compared to wild-type animals, both transgenic strains displayed alterations in the composition of lymphoid organs and in the dynamics of distinct immune cell subsets following immunization with the self-antigen PLP₁₈₅₋₂₀₆. However, ex-vivo T cell proliferation to PLP₁₈₅₋₂₀₆ peptide measured in immunized D(H)LMP2A and V(H)LMP2A mice was similar to that detected in immunized control mice. Further, clinical expression of experimental autoimmune encephalitis in both LMP2A strains was identical to that of wild-type mice. In conclusion, mice with skewed B cell differentiation driven by LMP2A expression in BCR-negative B cells do not show changes in the development of a T cell mediated disease model of autoimmunity, suggesting that compensatory mechanisms support the generation of T cell responses. PMID:24325711

  18. Foxa2 programs Th2 cell-mediated innate immunity in the developing lung.

    PubMed

    Chen, Gang; Wan, Huajing; Luo, Fengming; Zhang, Liqian; Xu, Yan; Lewkowich, Ian; Wills-Karp, Marsha; Whitsett, Jeffrey A

    2010-06-01

    After birth, the respiratory tract adapts to recurrent exposures to pathogens, allergens, and toxicants by inducing the complex innate and acquired immune systems required for pulmonary homeostasis. In this study, we show that Foxa2, expressed selectively in the respiratory epithelium, plays a critical role in regulating genetic programs influencing Th2 cell-mediated pulmonary inflammation. Deletion of the Foxa2 gene, encoding a winged helix/forkhead box transcription factor that is selectively expressed in respiratory epithelial cells, caused spontaneous pulmonary eosinophilic inflammation and goblet cell metaplasia. Loss of Foxa2 induced the recruitment and activation of myeloid dendritic cells and Th2 cells in the lung, causing increased production of Th2 cytokines and chemokines. Loss of Foxa2-induced expression of genes regulating Th2 cell-mediated inflammation and goblet cell differentiation, including IL-13, IL-4, eotaxins, thymus and activation-regulated chemokine, Il33, Ccl20, and SAM pointed domain-containing Ets transcription factor. Pulmonary inflammation and goblet cell differentiation were abrogated by treatment of neonatal Foxa2(Delta/Delta) mice with mAb against IL-4Ralpha subunit. The respiratory epithelium plays a central role in the regulation of Th2-mediated inflammation and innate immunity in the developing lung in a process regulated by Foxa2. PMID:20483781

  19. Autoxidation and cytotoxicity

    SciTech Connect

    Borg, D C; Schaich, K M; Elmore, Jr, J J

    1980-01-01

    A comprehensive synthesis, or reaction schema, to relate autoxidations of non-lipid compounds to lipid chain peroxidation in vivo is presented. This is done in the context of cytotoxic autoxidation reactions, and it is concluded that hydroxyl radicals produced by iron-dependent Fenton reactions serve as both primary toxicants and as sources of secondary toxicants. The latter stem from lipid chain peroxidation initiated by the Fenton-derived hydroxyl radicals, which are visualized as the obligate coupling step linking enzyme-dependent and non-enzymic autoxidations to potentially toxic outcomes.

  20. Immunohistochemical Analysis of the Natural Killer Cell Cytotoxicity Pathway in Human Abdominal Aortic Aneurysms

    PubMed Central

    Hinterseher, Irene; Schworer, Charles M.; Lillvis, John H.; Stahl, Elizabeth; Erdman, Robert; Gatalica, Zoran; Tromp, Gerard; Kuivaniemi, Helena

    2015-01-01

    Our previous analysis using genome-wide microarray expression data revealed extreme overrepresentation of immune related genes belonging the Natural Killer (NK) Cell Mediated Cytotoxicity pathway (hsa04650) in human abdominal aortic aneurysm (AAA). We followed up the microarray studies by immunohistochemical analyses using antibodies against nine members of the NK pathway (VAV1, VAV3, PLCG1, PLCG2, HCST, TYROBP, PTK2B, TNFA, and GZMB) and aortic tissue samples from AAA repair operations (n = 6) and control aortae (n = 8) from age-, sex- and ethnicity-matched donors from autopsies. The results confirmed the microarray results. Two different members of the NK pathway, HCST and GRZB, which act at different steps in the NK-pathway, were actively transcribed and translated into proteins in the same cells in the AAA tissue demonstrated by double staining. Furthermore, double staining with antibodies against CD68 or CD8 together with HCST, TYROBP, PTK2B or PLCG2 revealed that CD68 and CD8 positive cells expressed proteins of the NK-pathway but were not the only inflammatory cells involved in the NK-pathway in the AAA tissue. The results provide strong evidence that the NK Cell Mediated Cytotoxicity Pathway is activated in human AAA and valuable insight for future studies to dissect the pathogenesis of human AAA. PMID:25993291

  1. Cytotoxicity of denture adhesives.

    PubMed

    de Gomes, Pedro Sousa; Figueiral, Maria Helena; Fernandes, Maria Helena R; Scully, Crispian

    2011-12-01

    Ten commercially available denture adhesives, nine soluble formulations (six creams, three powders) and one insoluble product (pad), were analyzed regarding the cytotoxicity profile in direct and indirect assays using L929 fibroblast cells. In the direct assay, fibroblasts were seeded over the surface of a thick adhesive gel (5%, creams; 2.5%, powders and pad). In the indirect assay, cells were cultured in the presence of adhesive extracts prepared in static and dynamic conditions (0.5-2%, creams; 0.25-1%, powders and pad). Cell toxicity was assessed for cell viability/proliferation (MTT assay) and cell morphology (observation of the F-actin cytoskeleton organization by confocal laser scanning microscopy). Direct contact of the L929 fibroblasts with the thick adhesive gels caused no, or only a slight, decrease in cell viability/proliferation. The adhesive extracts (especially those prepared in dynamic conditions) caused significantly higher growth inhibition of fibroblasts and, in addition, caused dose- and time-dependent effects, throughout the 6-72 h exposure time. Also, dose-dependent effects on cell morphology, with evident disruption of the F-actin cytoskeleton organization, were seen in the presence of most adhesives. In conclusion, the adhesives possessed different degrees of cytotoxicity, but similar dose- and time-dependent biological profiles. PMID:20844908

  2. Cell-Mediated Immunity in Elite Controllers Naturally Controlling HIV Viral Load.

    PubMed

    Genovese, Luca; Nebuloni, Manuela; Alfano, Massimo

    2013-01-01

    The natural course of human immunodeficiency virus (HIV) infection is characterized by high viral load, depletion of immune cells, and immunodeficiency, ultimately leading to acquired immunodeficiency syndrome phase and the occurrence of opportunistic infections and diseases. Since the discovery of HIV in the early 1980s a naturally selected population of infected individuals has been emerged in the last years, characterized by being infected for many years, with viremia constantly below detectable level and poor depletion of immune cells. These individuals are classified as "elite controllers (EC) or suppressors" and do not develop disease in the absence of anti-retroviral therapy. Unveiling host factors and immune responses responsible for the elite status will likely provide clues for the design of therapeutic vaccines and functional cures. Scope of this review was to examine and discuss differences of the cell-mediated immune responses between HIV+ individuals with disease progression and EC. PMID:23577012

  3. Female Iberian wall lizards prefer male scents that signal a better cell-mediated immune response.

    PubMed

    López, Pilar; Martín, José

    2005-12-22

    In spite of the importance of chemoreception in sexual selection of lizards, only a few studies have examined the composition of chemical signals, and it is unknown whether and how chemicals provide honest information. Chemical signals might be honest if there were a trade-off between sexual advertisement and the immune system. Here, we show that proportions of cholesta-5,7-dien-3-ol in femoral secretions of male Iberian wall lizards (Podarcis hispanica) were related to their T-cell-mediated immune response. Thus, only males with a good immune system may allocate higher amounts of this chemical to signalling. Furthermore, females selected scents of males with higher proportions of cholesta-5,7-dien-3-ol and lower proportions of cholesterol. Thus, females might base their mate choice on the males' quality as indicated by the composition of their chemical signals. PMID:17148218

  4. Salmonella Modulates B Cell Biology to Evade CD8+ T Cell-Mediated Immune Responses

    PubMed Central

    Lopez-Medina, Marcela; Perez-Lopez, Araceli; Alpuche-Aranda, Celia; Ortiz-Navarrete, Vianney

    2014-01-01

    Although B cells and antibodies are the central effectors of humoral immunity, B cells can also produce and secrete cytokines and present antigen to helper T cells. The uptake of antigen is mainly mediated by endocytosis; thus, antigens are often presented by MHC-II molecules. However, it is unclear if B cells can present these same antigens via MHC-I molecules. Recently, Salmonella bacteria were found to infect B cells, allowing possible antigen cross-processing that could generate bacterial peptides for antigen presentation via MHC-I molecules. Here, we will discuss available knowledge regarding Salmonella antigen presentation by infected B cell MHC-I molecules and subsequent inhibitory effects on CD8+ T cells for bacterial evasion of cell-mediated immunity. PMID:25484884

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

    NASA Astrophysics Data System (ADS)

    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.

  6. Cell-mediated fiber recruitment drives extracellular matrix mechanosensing in engineered fibrillar microenvironments

    PubMed Central

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

    2015-01-01

    To investigate how cells sense stiffness in settings structurally similar to native extracellular matrices (ECM), 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 fibers, and bulk contraction of the material. While increasing the stiffness of flat hydrogel surfaces induced mesenchymal stem cell spreading and proliferation, increasing fiber stiffness instead suppressed spreading and proliferation depending on network architecture. Lower fiber stiffness permitted active cellular forces to recruit nearby fibers, dynamically increasing ligand density at the cell surface and promoting the formation of focal adhesions and related signaling. These studies demonstrate a departure from the well-described relationship between material stiffness and spreading established with hydrogel surfaces, and introduce fiber recruitment as a novel mechanism by which cells probe and respond to mechanics in fibrillar matrices. PMID:26461445

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

    PubMed

    Kawai, K; Meydani, S N; Urassa, W; Wu, D; Mugusi, F M; Saathoff, E; Bosch, R J; Villamor, E; Spiegelman, D; Fawzi, W W

    2014-07-01

    Limited studies exist regarding whether incorporating micronutrient supplements during tuberculosis (TB) treatment may improve cell-mediated immune response. We examined the effect of micronutrient supplementation on lymphocyte proliferation response to mycobacteria or T-cell mitogens in a randomized trial conducted on 423 patients with pulmonary TB. Eligible participants were randomly assigned to receive a daily dose of micronutrients (vitamins A, B-complex, C, E, and selenium) or placebo at the time of initiation of TB treatment. We found no overall effect of micronutrient supplements on lymphocyte proliferative responses to phytohaemagglutinin or purified protein derivatives in HIV-negative and HIV-positive TB patients. Of HIV-negative TB patients, the micronutrient group tended to show higher proliferative responses to concanavalin A than the placebo group, although the clinical relevance of this finding is not readily notable. The role of nutritional intervention in this vulnerable population remains an important area of future research. PMID:24093552

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

    PubMed

    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. PMID:24527702

  9. Optimistic Expectancies and Cell-Mediated Immunity: The Role of Positive Affect

    PubMed Central

    Segerstrom, Suzanne C.; Sephton, Sandra E.

    2014-01-01

    Optimistic expectancies affect many psychosocial outcomes and may also predict immune system changes and health, but the nature and mechanisms of any such physiological effects have not been identified. The present study related law-school expectancies to cell-mediated immunity (CMI), examining the within- and between-person components of this relationship and affective mediators. First-year law students (N = 124) completed questionnaire measures of expectancies and affect and received delayed-type hypersensitivity skin tests at five time points. A positive relationship between optimistic expectancies and CMI occurred, in which that changes in optimism correlated with changes in CMI. Likewise, changes in optimism predicted changes in positive and, to a lesser degree, negative affect, but the relationship between optimism and immunity was partially accounted for only by positive affect. This dynamic relationship between expectancies and immunity has positive implications for psychological interventions to improve health, particularly those that increase positive affect. PMID:20424083

  10. Molecular, genetic and stem cell-mediated therapeutic strategies for spinal muscular atrophy (SMA)

    PubMed Central

    Zanetta, Chiara; Riboldi, Giulietta; Nizzardo, Monica; Simone, Chiara; Faravelli, Irene; Bresolin, Nereo; Comi, Giacomo P; Corti, Stefania

    2014-01-01

    Spinal muscular atrophy (SMA) is an autosomal recessive motor neuron disease. It is the first genetic cause of infant mortality. It is caused by mutations in the survival motor neuron 1 (SMN1) gene, leading to the reduction of SMN protein. The most striking component is the loss of alpha motor neurons in the ventral horn of the spinal cord, resulting in progressive paralysis and eventually premature death. There is no current treatment other than supportive care, although the past decade has seen a striking advancement in understanding of both SMA genetics and molecular mechanisms. A variety of disease modifying interventions are rapidly bridging the translational gap from the laboratory to clinical trials. In this review, we would like to outline the most interesting therapeutic strategies that are currently developing, which are represented by molecular, gene and stem cell-mediated approaches for the treatment of SMA. PMID:24400925

  11. Explanatory style and cell-mediated immunity in elderly men and women.

    PubMed

    Kamen-Siegel, L; Rodin, J; Seligman, M E; Dwyer, J

    1991-01-01

    Correlated pessimistic explanatory style--the belief that negative events are caused by internal, stable, and global factors--with lowered immunocompetence in a sample of 26 older adults. Two measures of cell-mediated immunity--T-helper cell/T-suppressor cell ratio and T-lymphocyte response to mitogen challenge--were lower in individuals with a pessimistic style, controlling for the influence of current health, depression, medication, recent weight change, sleep, and alcohol use. A relative increase in the percentage of T-suppressor cells seemed to underlie this immunosuppression. Although the mechanism by which explanatory style might influence immune function remains unknown, we speculate that a pessimistic style might be an important psychological risk factor--at least among older people--in the early course of certain immune-mediated diseases. PMID:1915208

  12. Role of histamine in natural killer cell-mediated resistance against tumor cells.

    PubMed

    Hellstrand, K; Asea, A; Hermodsson, S

    1990-12-15

    The formation of lung metastases by i.v.-injected B16 melanoma (F1 and F10 strain) cells in Swiss albino, C57BL/6, and BALB/c mice was reduced by a single dose of histamine given 24 h before tumor cell inoculation. The antimetastatic effect of histamine was specifically mediated by histamine H2-receptors (H2R): it was blocked by the H2R antagonist ranitidine and mimicked by dimaprit, a specific H2R agonist but not by an H2R-inactive structural analog of this compound, nor-dimaprit, or the H1R agonist 2-thiazolyl-ethylamide. A single dose of any of the H2R antagonists ranitidine, tiotidine, famotidine, or cimetidine drastically augmented metastasis. Effects of H2R-interactive compounds on B16 metastasis required intact NK cells, as judged by the inability of histamine or ranitidine to affect B16 metastasis after NK cell depletion in vivo using antibodies to asialo-GM1. NK-cell-mediated lysis of YAC-1 lymphoma cells in vivo was enhanced by histamine and reduced by ranitidine within 4 h after inoculation of tumor cells. The antimetastatic effect of IL-2 was potentiated by histamine; in some experiments, combined treatment with a low dose of IL-2 (6000 U/kg) and histamine completely eliminated metastasis, whereas concomitant treatment with ranitidine abrogated antimetastatic effects of IL-2; animals treated with ranitidine and IL-2 displayed the same level of enhanced metastasis as those treated with ranitidine alone. The presented data are suggestive of an earlier unrecognized role for histamine in NK cell-mediated resistance against metastatic tumor cells. PMID:2147942

  13. T-cell-mediated drug hypersensitivity: immune mechanisms and their clinical relevance

    PubMed Central

    Cai, Fenfen; Lee, Frederick J; Pichler, Werner J

    2016-01-01

    T-cell-mediated drug hypersensitivity represents a significant proportion of immune mediated drug hypersensitivity reactions. In the recent years, there has been an increase in understanding the immune mechanisms behind T-cell-mediated drug hypersensitivity. According to hapten mechanism, drug specific T-cell response is stimulated by drug-protein conjugate presented on major histocompatibility complex (MHC) as it is presented as a new antigenic determinant. On the other hand, p-i concept suggests that a drug can stimulate T cells via noncovalent direct interaction with T-cell receptor and/or peptide-MHC. The drug binding site is quite variable and this leads to several different mechanisms within p-i concept. Altered peptide repertoire can be regarded as an 'atypical' subset of p-i concept since the mode of the drug binding and the binding site are essentially identical to p-i concept. However, the intracellular binding of abacavir to HLA-B*57:01 additionally results in alteration in peptide repertoire. Furthermore the T-cell response to altered peptide repertoire model is only shown for abacavir and HLA-B*57:01 and therefore it may not be generalised to other drug hypersensitivity. Danger hypothesis has been postulated to play an important role in drug hypersensitivity by providing signal 2 but its experimental data is lacking at this point in time. Furthermore, the recently described allo-immune response suggests that danger signal may be unnecessary. Finally, in view of these new understanding, the classification and the definition of type B adverse drug reaction should be revised. PMID:27141480

  14. T-cell-mediated drug hypersensitivity: immune mechanisms and their clinical relevance.

    PubMed

    Yun, James; Cai, Fenfen; Lee, Frederick J; Pichler, Werner J

    2016-04-01

    T-cell-mediated drug hypersensitivity represents a significant proportion of immune mediated drug hypersensitivity reactions. In the recent years, there has been an increase in understanding the immune mechanisms behind T-cell-mediated drug hypersensitivity. According to hapten mechanism, drug specific T-cell response is stimulated by drug-protein conjugate presented on major histocompatibility complex (MHC) as it is presented as a new antigenic determinant. On the other hand, p-i concept suggests that a drug can stimulate T cells via noncovalent direct interaction with T-cell receptor and/or peptide-MHC. The drug binding site is quite variable and this leads to several different mechanisms within p-i concept. Altered peptide repertoire can be regarded as an 'atypical' subset of p-i concept since the mode of the drug binding and the binding site are essentially identical to p-i concept. However, the intracellular binding of abacavir to HLA-B(*)57:01 additionally results in alteration in peptide repertoire. Furthermore the T-cell response to altered peptide repertoire model is only shown for abacavir and HLA-B(*)57:01 and therefore it may not be generalised to other drug hypersensitivity. Danger hypothesis has been postulated to play an important role in drug hypersensitivity by providing signal 2 but its experimental data is lacking at this point in time. Furthermore, the recently described allo-immune response suggests that danger signal may be unnecessary. Finally, in view of these new understanding, the classification and the definition of type B adverse drug reaction should be revised. PMID:27141480

  15. Mast cells mediate the immune suppression induced by dermal exposure to JP-8 jet fuel.

    PubMed

    Limón-Flores, Alberto Y; Chacón-Salinas, Rommel; Ramos, Gerardo; Ullrich, Stephen E

    2009-11-01

    Applying jet propulsion-8 (JP-8) jet fuel to the skin of mice induces immune suppression. Applying JP-8 to the skin of mice suppresses T-cell-mediated immune reactions including, contact hypersensitivity (CHS) delayed-type hypersensitivity and T-cell proliferation. Because dermal mast cells play an important immune regulatory role in vivo, we tested the hypothesis that mast cells mediate jet fuel-induced immune suppression. When we applied JP-8 to the skin of mast cell deficient mice CHS was not suppressed. Reconstituting mast cell deficient mice with wild-type bone marrow derived mast cells (mast cell "knock-in mice") restored JP-8-induced immune suppression. When, however, mast cells from prostaglandin E(2) (PGE(2))-deficient mice were used, the ability of JP-8 to suppress CHS was not restored, indicating that mast cell-derived PGE(2) was activating immune suppression. Examining the density of mast cells in the skin and lymph nodes of JP-8-treated mice indicated that jet fuel treatment caused an initial increase in mast cell density in the skin, followed by increased numbers of mast cells in the subcutaneous space and then in draining lymph nodes. Applying JP-8 to the skin increased mast cell expression of CXCR4, and increased the expression of CXCL12 by draining lymph node cells. Because CXCL12 is a chemoattractant for CXCR4+ mast cells, we treated JP-8-treated mice with AMD3100, a CXCR4 antagonist. AMD3100 blocked the mobilization of mast cells to the draining lymph node and inhibited JP-8-induced immune suppression. Our findings demonstrate the importance of mast cells in mediating jet fuel-induced immune suppression. PMID:19726579

  16. Gold Nanoparticles Cytotoxicity

    NASA Astrophysics Data System (ADS)

    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

  17. Cytotoxicity of halogenated graphenes

    NASA Astrophysics Data System (ADS)

    Teo, Wei Zhe; Khim Chng, Elaine Lay; Sofer, Zdeněk; Pumera, Martin

    2013-12-01

    Graphene and its family of derivatives possess unique and remarkable physicochemical properties which make them valuable materials for applications in many areas like electronics, energy storage and biomedicine. In response to the possibility of its large-scale manufacturing as commercial products in the future, an investigation was conducted to determine the cytotoxicity of one particular family of graphene derivatives, the halogenated graphenes, for the first time. Halogenated graphenes were prepared through thermal exfoliation of graphite oxide in gaseous chlorine, bromine or iodine atmospheres to yield chlorine- (TRGO-Cl), bromine- (TRGO-Br) and iodine-doped graphene (TRGO-I) respectively. 24 h exposure of human lung carcinoma epithelial cells (A549) to the three halogenated graphenes and subsequent cell viability assessments using methylthiazolyldiphenyl-tetrazolium bromide (MTT) and water-soluble tetrazolium salt (WST-8) assays revealed that all the halogenated graphenes examined are rather cytotoxic at the concentrations tested (3.125 μg mL-1 to 200 μg mL-1) and the effects are dose-dependent, with TRGO-Cl reducing the cell viability to as low as 25.7% at the maximum concentration of 200 μg mL-1. Their levels of cytotoxicity can be arranged in the order of TRGO-Cl > TRGO-Br > TRGO-I, and it is suggested that the amount of halogen present in the graphene material is the determining factor for the observed trend. Control experiments were carried out to test for possible nanomaterial-induced interference as a consequence of reaction between the halogenated graphenes and the viability markers (MTT/WST-8 reagent) or binding of the formazan products under cell-free conditions. The data obtained eliminate the probability of significant influence by these interferents as the change in the normalized percentage of formazan formed is relatively small and thorough washings were performed prior to the viability assessments to reduce the amount of halogenated

  18. MANGANESE CHLORIDE ENHANCES NATURAL CELL-MEDIATED IMMUNE EFFECTOR CELL FUNCTION: EFFECTS ON MACROPHAGES

    EPA Science Inventory

    A single intramuscular injection of MnCl2 in mice caused an increase in macrophage functional activity. Spleen cell antibody-dependent cellmediated cytotoxicity (ADCC) against both chicken erythrocytes and P815 tumor cell targets was enhanced 24 hours following a single injection...

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

    PubMed

    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. PMID:27375569

  20. Efficient Gene Transfection into Mammalian Cells Mediated by Cross-linked Polyethylenimine

    PubMed Central

    Dong, Wei; Li, Shufeng; Jin, Guanghui; Sun, Qiming; Ma, Dingyuan; Hua, Zichun

    2007-01-01

    25 kDa branched polyethylenimine (PEI) has successfully been used for in vitro and in vivo gene delivery approaches, but it is cytotoxic. Smaller PEIs are usually non-cytotoxic but less efficient. In order to enhance the gene delivery efficiency and minimize cytotoxicity of PEI, we explored to synthesize cross-linked PEIs with degradable bonds by reacting amines of small branched 2000 Da PEI with small diacrylate (1,4-butanediol diacrylate or ethyleneglycol dimethacrylate) for 2–6 hours. The efficiency of the cross-linked PEIs during in vitro delivering plasmid containing enhanced green fluorescent protein (EGFP) gene reporter and their cytotoxicity were assessed in melanoma B16F10 cell and other cell lines. In vivo gene delivery efficiency was evaluated by direct injection delivery of the EGFP plasmid/cross-linked PEI complexes into mice and by estimating the EGFP expression in animal muscles. Compared to commercially available 25-kDa branched PEI, the cross-linked PEIs reported here could mediate more efficient expression of reporter gene than the 25-kDa PEI control, 19-fold more efficiently in B16F10 cells, 17-fold in 293T cells, 2.3-fold in 3T3 cells, and they exhibited essentially nontoxic at their optimized condition for gene delivery. Furthermore the transfection activity of polyplexs was preserved in the presence of serum proteins. The muscle transfected with the cross-linked PEI prepared here exhibited normal morphology and excellent gene expression. The cross-linked PEIs reported here were evidently more efficient than the commercial 25-kD PEI control and had less cytotoxicity in gene delivery in vitro and in vivo.

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

    PubMed Central

    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. PMID:27375569

  2. RAT BLADDER CELL-MEDIATED MUTAGENESIS OF CHINESE HAMSTER V79 CELLS AND METABOLISM OF BENZO(A)PYRENE

    EPA Science Inventory

    Primary rat bladder epithelial cells were coculivated with Chinese hamster V79 cells in the presence of carcinogens, and the induction of 6-thioguanine resistance in the V79 cells was used as a marker of cell-mediated mutagenesis. The carcinogens dimethylnitrosamine, 7, 12-dimeth...

  3. Cell-mediated immunity in patients with chronic fatigue syndrome, healthy control subjects and patients with major depression.

    PubMed Central

    Lloyd, A; Hickie, I; Hickie, C; Dwyer, J; Wakefield, D

    1992-01-01

    The chronic fatigue syndrome (CFS) is characterized by severe persistent fatigue and neuropsychiatric symptoms. It has been proposed that the abnormalities in cell-mediated immunity which have been documented in patients with CFS may be attributable to a clinical depression, prevalent in patients with this disorder. Cell-mediated immune status was evaluated in patients with carefully defined CFS and compared with that of matched subjects with major depression (non-melancholic, non-psychotic) as well as healthy control subjects. Patients with CFS demonstrated impaired lymphocyte responses to phytohaemagglutinin (PHA) stimulation, and reduced or absent delayed-type hypersensitivity (DTH) skin responses when compared either with subjects with major depression or with healthy control subjects (P less than 0.05 for each analysis). Although depression is common in patients with CFS, the disturbances of cell-mediated immunity in this disorder differ in prevalence and magnitude from those associated with major depression. These observations strengthen the likelihood of a direct relationship between abnormal cell-mediated immunity and the etiology of CFS. PMID:1733640

  4. T cells recognizing leukemic CD34+ progenitor cells mediate the antileukemic effect of donor lymphocyte infusions for relapsed chronic myeloid leukemia after allogeneic stem cell transplantation

    PubMed Central

    Smit, Willem M.; Rijnbeek, Marion; van Bergen, Cornelis A. M.; Fibbe, Willem E.; Willemze, Roel; Falkenburg, J. H. Frederik

    1998-01-01

    Adoptive immunotherapy with donor lymphocyte infusions (DLI) is an effective treatment for relapsed chronic myeloid leukemia (CML) after allogeneic stem cell transplantation. To identify the effector and target cell populations responsible for the elimination of the leukemic cells in vivo we developed an assay to measure the frequency of T lymphocyte precursor cells capable of suppressing leukemic progenitor cells. Target cells in this assay were CML cells that were cultured in the presence of stem cell factor, interleukin 3, granulocyte–macrophage colony-stimulating factor, granulocyte colony-stimulating factor, and erythropoietin. [3H]thymidine incorporation at day 7 represented the proliferation of the progeny of the CD34+ CML progenitor cells, and not of the more mature CD34− CML cells. Effector cells were mononuclear cells, which were used in a limiting dilution analysis to measure the frequencies of CML progenitor cell-inhibitory lymphocyte precursors (PCILp) in peripheral blood of seven patients before and after DLI for relapsed CML. In the six patients who entered complete remission, a 5- to 100-fold increase of PCILp was found during the clinical response. In the patient with resistant relapse the frequency of PCILp was <10 per ml before and after DLI. Leukemia-reactive helper T lymphocyte precursor frequencies remained unchanged after DLI. A significant increase in cytotoxic T lymphocyte precursor frequency against more mature leukemic cells was found in only two responding patients. These results indicate that T cells specifically directed against CD34+ CML progenitor cells mediate the antileukemic effect of DLI. PMID:9707616

  5. Protection against henipaviruses in swine requires both, cell-mediated and humoral immune response.

    PubMed

    Pickering, Brad S; Hardham, John M; Smith, Greg; Weingartl, Eva T; Dominowski, Paul J; Foss, Dennis L; Mwangi, Duncan; Broder, Christopher C; Roth, James A; Weingartl, Hana M

    2016-09-14

    Hendra virus (HeV) and Nipah virus (NiV) are members of the genus Henipavirus, within the family Paramyxoviridae. Nipah virus has caused outbreaks of human disease in Bangladesh, Malaysia, Singapore, India and Philippines, in addition to a large outbreak in swine in Malaysia in 1998/1999. Recently, NiV was suspected to be a causative agent of an outbreak in horses in 2014 in the Philippines, while HeV has caused multiple human and equine outbreaks in Australia since 1994. A swine vaccine able to prevent shedding of infectious virus is of veterinary and human health importance, and correlates of protection against henipavirus infection in swine need to be better understood. In the present study, three groups of animals were employed. Pigs vaccinated with adjuvanted recombinant soluble HeV G protein (sGHEV) and challenged with HeV, developed antibody levels considered to be protective prior to the challenge (titers of 320). However, activation of the cell-mediated immune response was not detected, and the animals were only partially protected against challenge with 5×10(5) PFU of HeV per animal. In the second group, cross-neutralizing antibody levels against NiV in the sGHEV vaccinated animals did not reach protective levels, and with no activation of cellular immune memory, these animals were not protected against NiV. Only pigs orally infected with 5×10(4) PFU of NiV per animal were protected against nasal challenge with 5×10(5) PFU of NiV per animal. This group of pigs developed protective antibody levels, as well as cell-mediated immune memory. Peripheral blood mononuclear cells restimulated with UV-inactivated NiV upregulated IFN-gamma, IL-10 and the CD25 activation marker on CD4(+)CD8(+) T memory helper cells and to lesser extent on CD4(-)CD8(+) T cells. In conclusion, both humoral and cellular immune responses were required for protection of swine against henipaviruses. PMID:27544586

  6. Stimulatory effect of Eucalyptus essential oil on innate cell-mediated immune response

    PubMed Central

    Serafino, Annalucia; Vallebona, Paola Sinibaldi; Andreola, Federica; Zonfrillo, Manuela; Mercuri, Luana; Federici, Memmo; Rasi, Guido; Garaci, Enrico; Pierimarchi, Pasquale

    2008-01-01

    Background Besides few data concerning the antiseptic properties against a range of microbial agents and the anti-inflammatory potential both in vitro and in vivo, little is known about the influence of Eucalyptus oil (EO) extract on the monocytic/macrophagic system, one of the primary cellular effectors of the immune response against pathogen attacks. The activities of this natural extract have mainly been recognized through clinical experience, but there have been relatively little scientific studies on its biological actions. Here we investigated whether EO extract is able to affect the phagocytic ability of human monocyte derived macrophages (MDMs) in vitro and of rat peripheral blood monocytes/granulocytes in vivo in absence or in presence of immuno-suppression induced by the chemotherapeutic agent 5-fluorouracil (5-FU). Methods Morphological activation of human MDMs was analysed by scanning electron microscopy. Phagocytic activity was tested: i) in vitro in EO treated and untreated MDMs, by confocal microscopy after fluorescent beads administration; ii) in vivo in monocytes/granulocytes from peripheral blood of immuno-competent or 5-FU immuno-suppressed rats, after EO oral administration, by flow cytometry using fluorescein-labelled E. coli. Cytokine release by MDMs was determined using the BD Cytometric Bead Array human Th1/Th2 cytokine kit. Results EO is able to induce activation of MDMs, dramatically stimulating their phagocytic response. EO-stimulated internalization is coupled to low release of pro-inflammatory cytokines and requires integrity of the microtubule network, suggesting that EO may act by means of complement receptor-mediated phagocytosis. Implementation of innate cell-mediated immune response was also observed in vivo after EO administration, mainly involving the peripheral blood monocytes/granulocytes. The 5-FU/EO combined treatment inhibited the 5-FU induced myelotoxicity and raised the phagocytic activity of the granulocytic

  7. 5-Azacytidine treatment sensitizes tumor cells to T-cell mediated cytotoxicity and modulates NK cells in patients with myeloid malignancies.

    PubMed

    Gang, A O; Frøsig, T M; Brimnes, M K; Lyngaa, R; Treppendahl, M B; Grønbæk, K; Dufva, I H; Straten, P Thor; Hadrup, S R

    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 may have a role in this treatment regimen. We show here that 5-Azacytidine treatment leads to increased T-cell recognition of tumor cells. T-cell responses against a large panel of cancer-testis antigens were detected before treatment, and these responses were further induced upon initiation of treatment. These characteristics point to an ideal combination of 5-Azacytidine and immune therapy to preferentially boost T-cell responses against cancer-testis antigens. To initiate such combination therapy, essential knowledge is required about the general immune modulatory effect of 5-Azacytidine. We therefore examined potential treatment effects on both immune stimulatory (CD8 and CD4 T cells and Natural Killer (NK) cells) and immune inhibitory cell subsets (myeloid-derived suppressor cells and regulatory T cells). We observed a minor decrease and modulation of NK cells, but for all other populations no effects could be detected. Together, these data support a strategy for combining 5-Azacytidine treatment with immune therapy for potential clinical benefit. PMID:24681961

  8. 5-Azacytidine treatment sensitizes tumor cells to T-cell mediated cytotoxicity and modulates NK cells in patients with myeloid malignancies

    PubMed Central

    Gang, A O; Frøsig, T M; Brimnes, M K; Lyngaa, R; Treppendahl, M B; Grønbæk, K; Dufva, I H; Straten, P thor; Hadrup, S R

    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 may have a role in this treatment regimen. We show here that 5-Azacytidine treatment leads to increased T-cell recognition of tumor cells. T-cell responses against a large panel of cancer-testis antigens were detected before treatment, and these responses were further induced upon initiation of treatment. These characteristics point to an ideal combination of 5-Azacytidine and immune therapy to preferentially boost T-cell responses against cancer-testis antigens. To initiate such combination therapy, essential knowledge is required about the general immune modulatory effect of 5-Azacytidine. We therefore examined potential treatment effects on both immune stimulatory (CD8 and CD4 T cells and Natural Killer (NK) cells) and immune inhibitory cell subsets (myeloid-derived suppressor cells and regulatory T cells). We observed a minor decrease and modulation of NK cells, but for all other populations no effects could be detected. Together, these data support a strategy for combining 5-Azacytidine treatment with immune therapy for potential clinical benefit. PMID:24681961

  9. Purification and characterization of a fish granzymeA involved in cell-mediated immunity.

    PubMed

    Matsuura, Yuta; Yabu, Takeshi; Shiba, Hajime; Moritomo, Tadaaki; Nakanishi, Teruyuki

    2016-07-01

    Granzymes are serine proteases involved in the induction of cell death against non-self cells. The enzymes differ in their primary substrate specificity and have one of four hydrolysis activities: tryptase, Asp-ase, Met-ase and chymase. Although granzyme genes have been isolated from several fishes, evidence for their involvement in cytotoxicity has not yet been reported. In the present study, we attempted to purify and characterize a fish granzyme involved in cytotoxicity using ginbuna crucian carp. The cytotoxicity of leukocytes was significantly inhibited by the serine protease inhibitor ''3, 4-dichloroisocoumarin''. In addition, we found that granzymeA-like activity (hydrolysis of Z-GPR-MCA) was inhibited by the same inhibitor and significantly enhanced by allo-antigen stimulation in vivo. Proteins from leukocyte extracts were subjected to two steps of chromatographic purification using benzamidine-Sepharose and SP-Sepharose. The molecular weight of the purified enzyme was estimated to be 26,900 Da by SDS-PAGE analysis. The purified enzyme displayed a Km of 220 μM, a Kcat of 21.7 sec(-1) and a Kcat/Km of 98,796 sec(-1) M(-1) with an optimal pH of 9.5 for the Z-GPR-MCA substrate. The protease was totally inhibited by serine protease inhibitors and showed granzymeA-like substrate specificity. Therefore, we conclude that the purified enzyme belongs to the mammalian granzymeA (EC 3.4.21.78) and appears to be involved in cytotoxicity in fish. PMID:26872543

  10. Cytotoxicity of Hymenocallis expansa alkaloids.

    PubMed

    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. PMID:8229020

  11. Cytotoxic activity of Staphylococcus hyicus.

    PubMed

    Allaker, R P; Whitlock, M; Lloyd, D H

    1991-01-01

    Culture supernatants from a number of Staphylococcus hyicus strains caused toxic effects to both murine fibroblast and porcine keratinocyte cells in culture. The extent of cytotoxicity was shown to differ between strains and may provide an indication of strain virulence. Purification of cytotoxic activity produced by S. hyicus (strain P119) using preparative isoelectric-focussing demonstrated it to be cytolytic, haemolytic and non-proteolytic. The cytotoxin demonstrates certain properties in common with the delta haemolysin of Staphylococcus aureus. PMID:2024438

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

    NASA Astrophysics Data System (ADS)

    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.

  13. Candida mannan: chemistry, suppression of cell-mediated immunity, and possible mechanisms of action.

    PubMed Central

    Nelson, R D; Shibata, N; Podzorski, R P; Herron, M J

    1991-01-01

    The ability of Candida albicans to establish an infection involves multiple components of this fungal pathogen, but its ability to persist in host tissue may involve primarily the immunosuppressive property of a major cell wall glycoprotein, mannan. Mannan and oligosaccharide fragments of mannan are potent inhibitors of cell-mediated immunity and appear to reproduce the immune deficit of patients with the mucocutaneous form of candidiasis. However, neither the exact structures of these inhibitory species nor their mechanisms of action have yet been clearly defined. Different investigators have proposed that mannan or mannan catabolites act upon monocytes or suppressor T lymphocytes, but research from unrelated areas has provided still other possibilities for consideration. These include interference with cytokine activities, lymphocyte-monocyte interactions, and leukocyte homing. To stimulate further research of the immunosuppressive property of C. albicans mannan, we have reviewed (i) the relationship of mannan to other antigens and virulence factors of the fungus; (ii) the chemistry of mannan, together with methods for preparation of mannan and mannan fragments; and (iii) the historical evidence for immunosuppression by Candida mannan and the mechanisms currently proposed for this property; and (iv) we have speculated upon still other mechanisms by which mannan might influence host defense functions. It is possible that understanding the immunosuppressive effects of mannan will provide clues to novel therapies for candidiasis that will enhance the efficacy of both available and future anti-Candida agents. PMID:2004345

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

    PubMed Central

    2014-01-01

    Background 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. Results 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. Conclusions 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. PMID:24903770

  15. Hypothalamus-Pituitary-Adrenal cell-mediated immunity regulation in the Immune Restoration Inflammatory Syndrome

    PubMed Central

    Khakshooy, Allen; Chiappelli, Francesco

    2016-01-01

    Over one third of the patients sero-positive for the human immunodeficiency virus (HIV) with signs of the acquired immune deficiency syndrome (AIDS), and under treatment with anti-retroviral therapy (ART), develop the immune reconstitution inflammatory syndrome (IRIS). It is not clear what variables are that determine whether a patient with HIV/AIDS will develop ART-related IRIS, but the best evidence base thus far indicates that HIV/AIDS patients with low CD4 cell count, and HIV/AIDS patients whose CD4 count recovery shows a sharp slope, suggesting a particularly fast "immune reconstitution", are at greater risk of developing IRIS. Here, we propose the hypothesis that one important variable that can contribute to low CD4 cell count number and function in ART-treated HIV/AIDS patients is altered hypothalamic-pituitary-adrenal (HPA) cell-mediated immune (CMI) regulation. We discuss HPA-CMI deregulation in IRIS as the new frontier in comparative effectiveness research (CRE) for obtaining and utilizing the best evidence base for treatment of patients with HIV/AIDS in specific clinical settings. We propose that our hypothesis about altered HPA-CMI may extend to the pathologies observed in related viral infection, including Zika PMID:27212842

  16. Periodontal Ligament Stem Cell-Mediated Treatment for Periodontitis in Miniature Swine

    PubMed Central

    Liu, Yi; Zheng, Ying; Ding, Gang; Fang, Dianji; Zhang, Chunmei; Bartold, Peter Mark; Gronthos, Stan; Shi, Songtao; Wang, Songlin

    2009-01-01

    Periodontitis is a periodontal tissue infectious disease and the most common cause for tooth loss in adults. It has been linked to many systemic disorders, such as coronary artery disease, stroke, and diabetes. At present, there is no ideal therapeutic approach to cure periodontitis and achieve optimal periodontal tissue regeneration. In this study, we explored the potential of using autologous periodontal ligament stem cells (PDLSCs) to treat periodontal defects in a porcine model of periodontitis. The periodontal lesion was generated in the first molars area of miniature pigs by the surgical removal of bone and subsequent silk ligament suture around the cervical portion of the tooth. Autologous PDLSCs were obtained from extracted teeth of the miniature pigs and then expanded ex vivo to enrich PDLSC numbers. When transplanted into the surgically created periodontal defect areas, PDLSCs were capable of regenerating periodontal tissues, leading to a favorable treatment for periodontitis. This study demonstrates the feasibility of using stem cell-mediated tissue engineering to treat periodontal diseases. PMID:18238856

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

    PubMed Central

    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

  18. Triphasic mixture model of cell-mediated enzymatic degradation of hydrogels

    PubMed Central

    Vernerey, Franck J.; Greenwald, Eric C.; Bryant, Stephanie J.

    2012-01-01

    In order to engineer living tissue equivalents, a critical component is designing scaffolds, such as hydrogels, whose degradation kinetics can match that of matrix production by cells. However, cell-mediated enzymatic degradation of a hydrogel is highly complex and nonlinear process that is challenging to comprehend based solely on experimental observations. To address this issue, this study presents a triphasic mixture model of the enzyme/hydrogel system, that consists of a solid polymer network, water and enzyme. Based on mixture theory, rubber elasticity theory and the Michaelis-Menton kinetics for degradation, the model naturally incorporates a strong coupling between gel mechanical properties, the kinetics of degradation and the transport of enzyme through the gel. The model is then used to investigate the particular problem of a single spherical enzyme-producing cell, embedded in a spherical hydrogel domain, for which the governing equations can be cast within the cento-symmetric assumptions. The governing equations are subsequently solved using an implicit nonlinear finite element procedure in order to obtain the evolution of enzyme concentration and gel degradation through time and space. The model shows that two regimes of degradation behavior exist, whereby degradation is dominated either by diffusion or dominated by reaction kinetics. Depending on the enzyme properties and the initial hydrogel design, the temporal and spatial changes in gel cross-linking are dramatically impacted, a feature that is likely to strongly affect new tissue development. PMID:21809945

  19. Activation by SLAM Family Receptors Contributes to NK Cell Mediated “Missing-Self” Recognition

    PubMed Central

    Alari-Pahissa, Elisenda; Grandclément, Camille; Jeevan-Raj, Beena; Leclercq, Georges; Veillette, André; Held, Werner

    2016-01-01

    Natural Killer (NK) cells attack normal hematopoietic cells that do not express inhibitory MHC class I (MHC-I) molecules, but the ligands that activate NK cells remain incompletely defined. Here we show that the expression of the Signaling Lymphocyte Activation Molecule (SLAM) family members CD48 and Ly9 (CD229) by MHC-I-deficient tumor cells significantly contributes to NK cell activation. When NK cells develop in the presence of T cells or B cells that lack inhibitory MHC-I but express activating CD48 and Ly9 ligands, the NK cells’ ability to respond to MHC-I-deficient tumor cells is severely compromised. In this situation, NK cells express normal levels of the corresponding activation receptors 2B4 (CD244) and Ly9 but these receptors are non-functional. This provides a partial explanation for the tolerance of NK cells to MHC-I-deficient cells in vivo. Activating signaling via 2B4 is restored when MHC-I-deficient T cells are removed, indicating that interactions with MHC-I-deficient T cells dominantly, but not permanently, impair the function of the 2B4 NK cell activation receptor. These data identify an important role of SLAM family receptors for NK cell mediated “missing-self” reactivity and suggest that NK cell tolerance in MHC-I mosaic mice is in part explained by an acquired dysfunction of SLAM family receptors. PMID:27054584

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

    SciTech Connect

    Han, Jaehee; Kang, Dawon

    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.

  1. Cell mediated contraction in 3D cell-matrix constructs leads to spatially regulated osteogenic differentiation

    PubMed Central

    Klumpers, Darinka D.; Zhao, Xuanhe; Mooney, David J.; Smit, Theo H.

    2013-01-01

    During embryonic development, morphogenetic processes give rise to a variety of shapes and patterns that lead to functional tissues and organs. While the impact of chemical signals in these processes is widely studied, the role of physical cues is less understood. The aim of this study was to test the hypothesis that the interplay of cell mediated contraction and mechanical boundary conditions alone can result in spatially regulated differentiation in simple 3D constructs. An experimental model consisting of a 3D cell-gel construct and a finite element (FE) model were used to study the effect of cellular traction exerted by mesenchymal stem cells (MSCs) on an initially homogeneous matrix under inhomogeneous boundary conditions. A robust shape change is observed due to contraction under time-varying mechanical boundary conditions, which is explained by the finite element model. Furthermore, distinct local differences of osteogenic differentiation are observed, with a spatial pattern independent of osteogenic factors in the culture medium. Regions that are predicted to have experienced relatively high shear stress at any time during contraction, correlate with the regions of distinct osteogenesis. Taken together, these results support the underlying hypothesis that cellular contractility and mechanical boundary conditions alone can result in spatially regulated differentiation. These results will have important implications for tissue engineering and regeneration. PMID:23925497

  2. Epstein-Barr Virus Reactivation Associated with Diminished Cell-Mediated Immunity in Antarctic Expeditioners

    NASA Technical Reports Server (NTRS)

    Pierson, Duane L.; Mehta, Satish K.; Cooley, Helen; Dubow, Robin; Lugg, Desmond

    1999-01-01

    Reactivation of Epstein-Barr virus (EBV) and cell-mediated immune (CMI) responses were followed in 16 Antarctic expeditioners during winter-over isolation at two Australian National Antarctic Research Expedition stations. Delayed-type hypersensitivity skin testing was used as an indicator of the CMI response, which was evaluated two times before winter isolation and three times during isolation. At all five evaluation times, 8 or more of the 16 subjects had a diminished. CMI response. Diminished CMI was observed on every test occasion in 4/16 subjects; only 2/16 subjects exhibited normal CMI responses for all five tests. A polymerase chain reaction (PCR) assay was used to detect EBV DNA in saliva specimens collected before, after, and during 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 one 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<0.0005) when CMI responsiveness was diminished than when CMI status was normal. The findings indicate that the psychosocial, physical, and other stresses associated with working and living in physical isolation during the Antarctic winter results in diminished CMI and an accompanying increased reactivation and shedding of latent viruses.

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

    NASA Technical Reports Server (NTRS)

    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 < 0.0005) when DTH response was diminished than when DTH was normal. The findings indicate that the psychosocial, physical, and other stresses associated with working and living in physical isolation during the Antarctic winter result in diminished CMI and an accompanying increased reactivation and shedding of latent viruses.

  4. NLRC5 shields T lymphocytes from NK-cell-mediated elimination under inflammatory conditions

    PubMed Central

    Ludigs, Kristina; Jandus, Camilla; Utzschneider, Daniel T.; Staehli, Francesco; Bessoles, Stéphanie; Dang, Anh Thu; Rota, Giorgia; Castro, Wilson; Zehn, Dietmar; Vivier, Eric; Held, Werner; Romero, Pedro; Guarda, Greta

    2016-01-01

    NLRC5 is a transcriptional regulator of MHC class I (MHCI), which maintains high MHCI expression particularly in T cells. Recent evidence highlights an important NK–T-cell crosstalk, raising the question on whether NLRC5 specifically modulates this interaction. Here we show that NK cells from Nlrc5-deficient mice exhibit moderate alterations in inhibitory receptor expression and responsiveness. Interestingly, NLRC5 expression in T cells is required to protect them from NK-cell-mediated elimination upon inflammation. Using T-cell-specific Nlrc5-deficient mice, we show that NK cells surprisingly break tolerance even towards ‘self' Nlrc5-deficient T cells under inflammatory conditions. Furthermore, during chronic LCMV infection, the total CD8+ T-cell population is severely decreased in these mice, a phenotype reverted by NK-cell depletion. These findings strongly suggest that endogenous T cells with low MHCI expression become NK-cell targets, having thus important implications for T-cell responses in naturally or therapeutically induced inflammatory conditions. PMID:26861112

  5. Using Molecular Phenotyping to Guide Improvements in the Histologic Diagnosis of T Cell-Mediated Rejection.

    PubMed

    Reeve, J; Chang, J; Salazar, I D R; Lopez, M Merino; Halloran, P F

    2016-04-01

    Recognition that some lesions typical of T cell-mediated rejection (TCMR) also occur in antibody-mediated rejection requires revision of the histologic TCMR definition. To guide this process, we assessed the relative importance of various lesions and the performance of new histology diagnostic algorithms, using molecular TCMR scores as histology-independent estimates of true TCMR. In 703 indication biopsies, random forest analysis and logistic regression indicated that interstitial infiltrate (i-lesions) and tubulitis (t-lesions) were the key histologic predictors of molecular TCMR, with arteritis (v-lesions) having less importance. Histology predicted molecular TCMR more accurately when diagnoses were assigned by strictly applying the Banff rules to the lesion scores and redefining isolated v-lesion TCMR. This improved prediction from area under the curve (AUC) 0.70 with existing rules to AUC 0.80. Further improvements were achieved by introducing more categories to reflect inflammation (AUC 0.84), by summing the lesion scores (AUC 0.85) and by logistic regression (AUC 0.90). We concluded that histologic assessment of TCMR can be improved by placing more emphasis on i- and t-lesions and incorporating new algorithms for diagnosis. Nevertheless, some discrepancies between histologic and molecular diagnoses persist, partially due to the inherent nonspecificity of i- and t-lesions, and molecular methods will be required to help resolve these cases. PMID:26730747

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

    SciTech Connect

    Iseki, Minoru; Ikuta, Togo; Kobayashi, Tetsuya; Kawajiri, Kaname . E-mail: kawajiri@cancer-c.pref.saitama.jp

    2005-06-17

    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{sup Cip1}, which was abolished by pretreatment with actinomycin D. A p38 MAPK specific inhibitor, SB203580, blocked the increase of p21{sup Cip1} mRNA in response to MC. Treatment with indigo, another AhR ligand, failed to increase of p21{sup Cip1} mRNA, although up-regulation of mRNA for CYP1A1 was observed. These data suggest AhR in Leydig cells mediates growth inhibition by inducing p21{sup Cip1}.

  7. Hypothalamus-Pituitary-Adrenal cell-mediated immunity regulation in the Immune Restoration Inflammatory Syndrome.

    PubMed

    Khakshooy, Allen; Chiappelli, Francesco

    2016-01-01

    Over one third of the patients sero-positive for the human immunodeficiency virus (HIV) with signs of the acquired immune deficiency syndrome (AIDS), and under treatment with anti-retroviral therapy (ART), develop the immune reconstitution inflammatory syndrome (IRIS). It is not clear what variables are that determine whether a patient with HIV/AIDS will develop ART-related IRIS, but the best evidence base thus far indicates that HIV/AIDS patients with low CD4 cell count, and HIV/AIDS patients whose CD4 count recovery shows a sharp slope, suggesting a particularly fast "immune reconstitution", are at greater risk of developing IRIS. Here, we propose the hypothesis that one important variable that can contribute to low CD4 cell count number and function in ART-treated HIV/AIDS patients is altered hypothalamic-pituitary-adrenal (HPA) cell-mediated immune (CMI) regulation. We discuss HPA-CMI deregulation in IRIS as the new frontier in comparative effectiveness research (CRE) for obtaining and utilizing the best evidence base for treatment of patients with HIV/AIDS in specific clinical settings. We propose that our hypothesis about altered HPA-CMI may extend to the pathologies observed in related viral infection, including Zika. PMID:27212842

  8. Proteasome immunosubunits protect against the development of CD8 T-cell-mediated autoimmune diseases

    PubMed Central

    Zaiss, Dietmar M.W.; Bekker, Cornelis P.J.; Gröne, Andrea; Lie, Benedicte A.; Sijts, Alice J.A.M.

    2011-01-01

    Exposure of cells to inflammatory cytokines induces the expression of three proteasome immunosubunits, two of which are encoded in the MHC-II region. The induced subunits replace their constitutive homologues in newly formed, so called immunoproteasomes. Immunosubunit incorporation enhances the proteasome’ proteolytic activity and modifies the proteasome’ cleavage site preferences, which improves the generation of many MHC-I presented peptides and shapes the fine-specificity of pathogen-specific CD8 T cell responses. We here report on a second effect of immunoproteasome formation on CD8 T cell responses. We show that mice deficient for the immunosubunits β5i/LMP7 and β2i/MECL-1 develop early-stage multi-organ autoimmunity following irradiation and BM transplantation. Disease symptoms are caused by CD8 T cells and transferrable into immunosubunit-deficient, RAG1-deficient mice. Moreover, using the human Type 1 Diabetes Genetics Consortium (T1DGC) MHC dataset, we identified two SNPs within the β5i/LMP7-encoding gene sequences, that were in strong linkage disequilibrium (LD), as independent genetic risk factors for T1D development in humans. Strikingly, these SNPs significantly enhanced the risk conferred by HLA haplotypes that were formerly shown to predispose for T1D. These data suggest that inflammation-induced immunosubunit expression in peripheral tissues constitutes a mechanism that prevents the development of CD8 T cell mediated autoimmune diseases. PMID:21804012

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

    PubMed

    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

  10. Is cell-mediated immunity related to the evolution of life-history strategies in birds?

    PubMed Central

    Tella, José L; Scheuerlein, Alex; Ricklefs, Robert E

    2002-01-01

    According to life-history theory, the development of immune function should be balanced through evolutionary optimization of the allocation of resources to reproduction and through mechanisms that promote survival. We investigated interspecific variability in cell-mediated immune response (CMI), as measured by the phytohaemagglutinin (PHA) assay, in relation to clutch size, longevity and other life-history traits in 50 species of birds. CMI exhibited significant repeatability within species, and PHA responses in chicks were consistently stronger than in adults. Univariate tests showed a variety of significant relationships between the CMI of both chicks and adults with respect to size, development period and lifespan, but not clutch size or prevalence of blood parasites in adults. Multivariate analyses confirmed these patterns but independent variables were too highly correlated to isolate unique influences on CMI. The positive relationship of chick CMI to nestling period is further complicated by a parallel relationship of chick CMI to the age at testing. However, multivariate analysis showed that chick CMI varies uniquely with length of the nestling period. Adult CMI was associated with a strong life-history axis of body size, development rate and longevity. Therefore, adult CMI may be associated with prevention and repair mechanisms related to long lifespan, but it also may be allometrically related to body size through other pathways. Neither chick CMI nor adult CMI was related to clutch size, contradicting previous results linking parasite-related mortality to CMI and the evolution of clutch size (reproductive investment) in birds. PMID:12028764

  11. Cell mediated immune response of the Mediterranean sea urchin Paracentrotus lividus after PAMPs stimulation.

    PubMed

    Romero, A; Novoa, B; Figueras, A

    2016-09-01

    The Mediterranean sea urchin (Paracentrotus lividus) is of great ecological and economic importance for the European aquaculture. Yet, most of the studies regarding echinoderm's immunological defense mechanisms reported so far have used the sea urchin Strongylocentrotus purpuratus as a model, and information on the immunological defense mechanisms of Paracentrotus lividus and other sea urchins, is scarce. To remedy this gap in information, in this study, flow cytometry was used to evaluate several cellular immune mechanisms, such as phagocytosis, cell cooperation, and ROS production in P. lividus coelomocytes after PAMP stimulation. Two cell populations were described. Of the two, the amoeboid-phagocytes were responsible for the phagocytosis and ROS production. Cooperation between amoeboid-phagocytes and non-adherent cells resulted in an increased phagocytic response. Stimulation with several PAMPs modified the phagocytic activity and the production of ROS. The premise that the coelomocytes were activated by the bacterial components was confirmed by the expression levels of two cell mediated immune genes: LPS-Induced TNF-alpha Factor (LITAF) and macrophage migration inhibitory factor (MIF). These results have helped us understand the cellular immune mechanisms in P. lividus and their modulation after PAMP stimulation. PMID:27113124

  12. CD8+ T Cell-Mediated Neuronal Dysfunction and Degeneration in Limbic Encephalitis

    PubMed Central

    Ehling, Petra; Melzer, Nico; Budde, Thomas; Meuth, Sven G.

    2015-01-01

    Autoimmune inflammation of the limbic gray matter structures of the human brain has recently been identified as major cause of mesial temporal lobe epilepsy with interictal temporal epileptiform activity and slowing of the electroencephalogram, progressive memory disturbances, as well as a variety of other behavioral, emotional, and cognitive changes. Magnetic resonance imaging exhibits volume and signal changes of the amygdala and hippocampus, and specific anti-neuronal antibodies binding to either intracellular or plasma membrane neuronal antigens can be detected in serum and cerebrospinal fluid. While effects of plasma cell-derived antibodies on neuronal function and integrity are increasingly becoming characterized, potentially contributing effects of T cell-mediated immune mechanisms remain poorly understood. CD8+ T cells are known to directly interact with major histocompatibility complex class I-expressing neurons in an antigen-specific manner. Here, we summarize current knowledge on how such direct CD8+ T cell–neuron interactions may impact neuronal excitability, plasticity, and integrity on a single cell and network level and provide an overview on methods to further corroborate the in vivo relevance of these mechanisms mainly obtained from in vitro studies. PMID:26236280

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

    PubMed

    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. PMID:24268314

  14. Mast Cells Mediate Acute Kidney Injury through the Production of TNF

    PubMed Central

    Summers, Shaun A.; Chan, Jacky; Gan, Poh-Yi; Dewage, Lakshi; Nozaki, Yuji; Steinmetz, Oliver M.; Nikolic-Paterson, David J.; Kitching, A. Richard

    2011-01-01

    Leukocyte recruitment contributes to acute kidney injury (AKI), but the mechanisms by which leukocytes promote injury are not completely understood. The degranulation of mast cells releases inflammatory molecules, including TNF, but whether these cells participate in the pathogenesis of AKI is unknown. Here, we induced AKI with cisplatin in mast cell-deficient and wild-type mice. Compared with wild-type mice, deficiency of mast cells attenuated renal injury, reduced serum levels of TNF, and reduced recruitment of leukocytes to the inflamed kidney. Mast cell-deficient mice also exhibited significantly lower intrarenal expression of leukocyte chemoattractants. Mast cell-deficient mice reconstituted with mast cells from wild-type mice exhibited similar cisplastin-induced renal damage and serum levels of TNF as wild-type mice. In contrast, mast cell-deficient mice reconstituted with mast cells from TNF-deficient mice continued to demonstrate significant attenuation of cisplatin-induced renal injury. Furthermore, the mast-cell stabilizer sodium chromoglycate also significantly abrogated renal injury in this model of AKI. Taken together, these results suggest that mast cells mediate AKI through the production of TNF. PMID:22021718

  15. NKG2D Signaling Leads to NK Cell Mediated Lysis of Childhood AML

    PubMed Central

    Schlegel, Patrick; Ditthard, Kerstin; Lang, Peter; Mezger, Markus; Michaelis, Sebastian; Handgretinger, Rupert; Pfeiffer, Matthias

    2015-01-01

    Natural killer cells have been shown to be relevant in the recognition and lysis of acute myeloid leukemia. In childhood acute lymphoblastic leukemia, it was shown that HLA I expression and KIR receptor-ligand mismatch significantly impact ALL cytolysis. We characterized 14 different primary childhood AML blasts by flow cytometry including NKG2D ligands. Further HLA I typing of blasts was performed and HLA I on the AML blasts was quantified. In two healthy volunteer NK cell donors HLA I typing and KIR genotyping were done. Blasts with high NKG2D ligand expression had significantly higher lysis by isolated NK cells. Grouping the blasts by NKG2D ligand expression led to a significant inverse correlation of HLA I expression and cytolysis in NKG2D low blasts. Furthermore, a significant positive correlation of NKG2D ligand expression and blast cytolysis was shown. No impact of KIR ligand-ligand mismatch was found but a significantly increased lysis of homozygous C2 blasts by KIR2DL1 negative NK cells (donor B) was revealed. In conclusion, NKG2D signaling leads to NK cell mediated lysis of childhood AML despite high HLA I expression. PMID:26236752

  16. First Line of Defense: Innate Cell-Mediated Control of Pulmonary Aspergillosis

    PubMed Central

    Espinosa, Vanessa; Rivera, Amariliz

    2016-01-01

    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. PMID:26973640

  17. Essential role for caspase 8 in T-cell homeostasis and T-cell-mediated immunity

    PubMed Central

    Salmena, Leonardo; Lemmers, Benedicte; Hakem, Anne; Matysiak-Zablocki, Elzbieta; Murakami, Kiichi; Au, P.Y. Billie; Berry, Donna M.; Tamblyn, Laura; Shehabeldin, Amro; Migon, Eva; Wakeham, Andrew; Bouchard, Denis; Yeh, Wen Chen; McGlade, Jane C.; Ohashi, Pamela S.; Hakem, Razqallah

    2003-01-01

    Defects in death receptor-mediated apoptosis have been linked to cancer and autoimmune disease in humans. The in vivo role of caspase 8, a component of this pathway, has eluded analysis in postnatal tissues because of the lack of an appropriate animal model. Targeted disruption of caspase 8 is lethal in utero. We generated mice with a targeted caspase 8 mutation that is restricted to the T-cell lineage. Despite normal thymocyte development in the absence of caspase 8, we observed a marked decrease in the number of peripheral T-cells and impaired T-cell response ex vivo to activation stimuli. caspase 8 ablation protected thymocytes and activated T-cells from CD95 ligand but not anti-CD3-induced apoptosis, or apoptosis activated by agents that are known to act through the mitochondria. caspase 8 mutant mice were unable to mount an immune response to viral infection, indicating that caspase 8 deletion in T-cells leads to immunodeficiency. These findings identify an essential, cell-stage-specific role for caspase 8 in T-cell homeostasis and T-cell-mediated immunity. This is consistent with the recent identification of caspase 8 mutations in human immunodeficiency. PMID:12654726

  18. Herpesvirus ateles and herpesvirus saimiri transform marmoset T cells into continuously proliferating cell lines that can mediate natural killer cell-like cytotoxicity.

    PubMed Central

    Johnson, D R; Jondal, M

    1981-01-01

    Herpesvirus ateles (HVA) and herpesvirus saimiri (HVS) have the capacity to transform cotton-topped marmoset T lymphocytes into continuously proliferating cell lines that retain some functions associated with cell-mediated immunity. In the present paper, we demonstrate that HVA/HVS-transformed T cell lines are cytotoxic in a short-term 51Cr release assay and that this killing resembles killing by marmoset natural killer (NK) cells. The relationship between NK cells and HVA/HVS-transformed killer cell lines is discussed in view of present knowledge of the origin and function of the NK system. It is suggested that the described cytotoxic cell lines may be useful for further defining cellular cytotoxicity with regard to cell surface recognition, regulatory events, and lytic mechanisms. PMID:6273869

  19. Polypropylene Sulfide Nanoparticle p24 Vaccine Promotes Dendritic Cell-Mediated Specific Immune Responses against HIV-1.

    PubMed

    Caucheteux, Stephan M; Mitchell, John P; Ivory, Matthew O; Hirosue, Sachiko; Hakobyan, Svetlana; Dolton, Garry; Ladell, Kristin; Miners, Kelly; Price, David A; Kan-Mitchell, June; Sewell, Andrew K; Nestle, Frank; Moris, Arnaud; Karoo, Richard O; Birchall, James C; Swartz, Melody A; Hubbel, Jeffrey A; Blanchet, Fabien P; Piguet, Vincent

    2016-06-01

    Delivery of vaccine formulations into the dermis using antigen-coated microneedle patches is a promising and safe approach because of efficient antigen delivery and safety. We evaluated an intradermal vaccine using HIV-1 p24 Gag peptide-conjugated polypropylene sulfide nanoparticles to induce immunity against HIV-1. This peptide-conjugated polypropylene sulfide nanoparticle formulation did not accelerate the maturation of blood- or skin-derived subsets of dendritic cells, either generated in vitro or purified ex vivo, despite efficient uptake in the absence of adjuvant. Moreover, dendritic cell-mediated capture of particulate antigen in this form induced potent HIV-1-specific CD4(+) T-cell responses, as well as B-cell-mediated antibody production. Nanoparticle-based intradermal antigen delivery may therefore provide a new option in the global effort to develop an effective vaccine against HIV-1. PMID:26896775

  20. Cell-mediated immune responses after immunization of healthy seronegative children with varicella vaccine: kinetics and specificity.

    PubMed

    Watson, B; Keller, P M; Ellis, R W; Starr, S E

    1990-10-01

    Humoral and cell-mediated immune responses were determined in seronegative children immunized with live attenuated Oka strain varicella vaccine. At 2 weeks after immunization, 80% of children had detectable lymphocyte proliferation to varicella-zoster virus (VZV) antigens, while only 40% had antibodies to VZV as detected by ELISA. By 6 weeks after immunization, 97% of children seroconverted, and 95% of these responded to VZV antigens in the proliferation assay. A high proportion of immunized children also responded in the proliferation assay to purified glycoproteins I, II, and III of VZV. These results indicate that most children develop a broad cell-mediated immune response to VZV antigens within weeks after immunization with varicella vaccine. PMID:2169495

  1. Influence of brachytherapy ( sup 192 Ir afterloading) on cell-mediated immune reactions in patients with stage I endometrial cancer

    SciTech Connect

    Gerstner, G.J.; Kucera, H.; Kudlacek, S.; Micksche, M. )

    1989-11-01

    The influence of radiation therapy on cell-mediated immune reactions in cancer patients seems to depend on source, dose, and area of irradiation, as well as on the variables reflected by the patient population investigated. In the present study we demonstrated that brachytherapy ({sup 192}Ir afterloading), applied to patients with inoperable stage I endometrial cancer, has no immediate or sustained effect on lymphocyte function. Both lymphocyte mitogen response and natural killer cell (NK) activity are not significantly changed in terms of baseline values compared with test results during and after therapy. Brachytherapy, as used in this study, has no influence on cell-mediated immunity in patients with endometrial cancer stage I.

  2. Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure

    PubMed Central

    Weng, Hong-Lei; Cai, Xiaobo; Yuan, Xiaodong; Liebe, Roman; Dooley, Steven; Li, Hai; Wang, Tai-Ling

    2015-01-01

    Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called “second pathway of liver regeneration.” The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin. PMID:26136687

  3. Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure.

    PubMed

    Weng, Hong-Lei; Cai, Xiaobo; Yuan, Xiaodong; Liebe, Roman; Dooley, Steven; Li, Hai; Wang, Tai-Ling

    2015-01-01

    Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called "second pathway of liver regeneration." The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin. PMID:26136687

  4. NKG2D and DNAM-1 Ligands: Molecular Targets for NK Cell-Mediated Immunotherapeutic Intervention in Multiple Myeloma

    PubMed Central

    Fionda, Cinzia; Soriani, Alessandra; Zingoni, Alessandra; Santoni, Angela; Cippitelli, Marco

    2015-01-01

    A pivotal strategy to improve NK cell-mediated antitumor activity involves the upregulation of activating ligands on tumor cells. Enhancement of NK cell-mediated recognition of multiple myeloma cells was reported by us and others showing increased surface expression of NKG2D and DNAM-1 ligands on tumor cells following treatment with a number of chemotherapeutic agents, such as genotoxic drugs or inhibitors of proteasome, histone deacetylases, GSK3, and HSP-90. These compounds have the capability to affect tumor survival but also to activate specific transduction pathways associated with the upregulation of different NK cell activating ligands on the tumor cells. Here, we will summarize and discuss the molecular pathways whereby these drugs can regulate the expression of NK cell activating ligands in multiple myeloma cells. PMID:26161387

  5. Sequestration of inhaled particulate antigens by lung phagocytes. A mechanism for the effective inhibition of pulmonary cell-mediated immunity.

    PubMed Central

    MacLean, J. A.; Xia, W.; Pinto, C. E.; Zhao, L.; Liu, H. W.; Kradin, R. L.

    1996-01-01

    Dendritic cells (DCs) have emerged as the dominant antigen-presenting cells (APCs) of the lung, playing a vital role in the induction of cell-mediated immunity to inhaled antigens. We have previously demonstrated that an airway challenge with the soluble antigen hen egg lysozyme yields rapid acquisition of specific antigen-presenting cell activity by purified pulmonary DCs and a cell-mediated immune response in the lung upon secondary challenge. To examine how a particulate antigen leads to a cell-mediated response in vivo, graded concentrations of heat-killed Listeria (HKL) were injected intratracheally into Lewis rats. The bacteria were rapidly ingested by lung macrophages and polymorphonuclear leukocytes. The ability of purified pulmonary DCs pulsed in vivo by an airway challenge with HKL to subsequently stimulate HKL-specific responses ex vivo showed a threshold response, requiring a dose in excess of 10(9) organisms/rat. By contrast, all dosages of HKL yielded specific sensitization of lymphocytes in the draining bilar nodes. Pulmonary DCs purified from rats after a secondary in vivo airway challenge with HKL at day 14 were ineffective antigen-presenting cells except at high dosages of antigen. The generation of cell-mediated pulmonary inflammation paralleled the antigen-presenting cell activity of pulmonary DCs and was observed only at high antigen dosages. Hen egg lysozyme immobilized onto polystyrene beads and injected intratracheally yielded comparable results to those observed with HKL. We suggest that a pulmonary cellular immune response is generated to an inhaled particulate antigen when the protective phagocytic capacities of the lung are exceeded and antigen is able to interact directly with interstitial DCs. The diversion of particulate antigens by pulmonary phagocytes may help to limit undesirable pulmonary inflammation while allowing the generation of antigen-specific immune lymphocytes in vivo. Images Figure 2 Figure 4 Figure 5 Figure 7 Figure 9

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

    PubMed Central

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

    2013-01-01

    Background 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. Objective 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. Methods 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. Currents 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. Results 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. Conclusion 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. PMID:23808707

  7. Electrospun nanofibrous scaffolds increase the efficacy of stem cell-mediated therapy of surgically resected glioblastoma.

    PubMed

    Bagó, Juli R; Pegna, Guillaume J; Okolie, Onyi; Mohiti-Asli, Mahsa; Loboa, Elizabeth G; Hingtgen, Shawn D

    2016-06-01

    Engineered stem cell (SC)-based therapy holds enormous promise for treating the incurable brain cancer glioblastoma (GBM). Retaining the cytotoxic SCs in the surgical cavity after GBM resection is one of the greatest challenges to this approach. Here, we describe a biocompatible electrospun nanofibrous scaffold (bENS) implant capable of delivering and retaining tumor-homing cytotoxic stem cells that suppress recurrence of post-surgical GBM. As a new approach to GBM therapy, we created poly(l-lactic acid) (PLA) bENS bearing drug-releasing human mesenchymal stem cells (hMSCs). We discovered that bENS-based implant increased hMSC retention in the surgical cavity 5-fold and prolonged persistence 3-fold compared to standard direct injection using our mouse model of GBM surgical resection/recurrence. Time-lapse imaging showed cytotoxic hMSC/bENS treatment killed co-cultured human GBM cells, and allowed hMSCs to rapidly migrate off the scaffolds as they homed to GBMs. In vivo, bENS loaded with hMSCs releasing the anti-tumor protein TRAIL (bENS(sTR)) reduced the volume of established GBM xenografts 3-fold. Mimicking clinical GBM patient therapy, lining the post-operative GBM surgical cavity with bENS(sTR) implants inhibited the re-growth of residual GBM foci 2.3-fold and prolonged post-surgical median survival from 13.5 to 31 days in mice. These results suggest that nanofibrous-based SC therapies could be an innovative new approach to improve the outcomes of patients suffering from terminal brain cancer. PMID:27016620

  8. Kupffer cell-mediated exacerbation of methimazole-induced acute liver injury in rats.

    PubMed

    Akai, Sho; Uematsu, Yasuaki; Tsuneyama, Koichi; Oda, Shingo; Yokoi, Tsuyoshi

    2016-05-01

    Methimazole (MTZ), an anti-thyroid drug, is known to cause liver injury in humans. It has been demonstrated that MTZ-induced liver injury in Balb/c mice is accompanied by T helper (Th) 2 cytokine-mediated immune responses; however, there is little evidence for immune responses associated with MTZ-induced liver injury in rats. To investigate species differences in MTZ-induced liver injury, we administered MTZ with a glutathione biosynthesis inhibitor, L-buthionine-S,R-sulfoximine (BSO), to F344 rats and subsequently observed an increase in plasma alanine aminotransferase (ALT) and high-mobility group box 1 (HMGB1), which are associated with hepatic lesions. The hepatic mRNA expression of innate immune-related genes significantly increased in BSO- and MTZ-treated rats, but the change in Th2-related genes was not much greater than the change observed in the previous mouse study. Moreover, an increase in Kupffer cells and an induction of the phosphorylation of extracellular signal-regulated kinase (ERK)/c-Jun N-terminal kinase (JNK) proteins were accompanied by an increase in Toll-like receptor 4 (TLR4) expression, indicating that Kupffer cell activation occurs through HMGB1-TLR4 signaling. To elucidate the mechanism of liver injury in rats, gadolinium chloride, which inactivates the function of Kupffer cells, was administered before BSO and MTZ administration. The gadolinium chloride treatment significantly suppressed the increased ALT, which was accompanied by decreased hepatic mRNA expression related to innate immune responses and ERK/JNK phosphorylation. In conclusion, Kupffer cell-mediated immune responses are crucial factors for the exacerbation of MTZ-induced liver injury in rats, indicating apparent species differences in the immune-mediated exacerbation of liver injury between mice and rats. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26177832

  9. Roscovitine Suppresses CD4+ T Cells and T Cell-Mediated Experimental Uveitis

    PubMed Central

    Zhang, Zili; Liu, Qi; Leskov, Konstantin S.; Wu, Xiumei; Duan, Jie; Zhang, Gary L.; Hall, Mark; Rosenbaum, James T.

    2013-01-01

    Background T cells are essential for the development of uveitis and other autoimmune diseases. After initial activation, CD4+ lymphocytes express the co-stimulatory molecule OX40 that plays an important role in T cell proliferation. Cyclin dependent kinase 2 (CdK2) plays a pivotal role in the cell cycle transition from G1 to S phase. In addition, recent research has implicated CdK2 in T cell activation. Thus, we sought to test the immunosuppressive effect of roscovitine, a potent CdK2 inhibitor, on CD4+ T cell activation, proliferation, and function. Design and Methods Mouse CD4+ T cells were activated by anti-CD3 and anti-CD28 antibodies. The expression of OX40, CD44, and CdK2 were analyzed by flow cytometry. In addition, cell cycle progression and apoptosis of control and roscovitine-treated T lymphocytes were measured by BrdU incorporation and annexin V assay, respectively. Furthermore, the immunoregulatory effect of roscovitine was evaluated in both ovalbumin-induced uveitis and experimental autoimmune uveitis (EAU) models. Results In this study, we found that T cell activation induced OX40 expression. Cell cycle analysis showed that more CD4+OX40+ cells entered S phase than OX40- T cells. Concurrently, CD4+OX40+ cells had a higher level of CdK2 expression. Roscovitine treatment blocked activated CD4+ cells from entering S phase. In addition, roscovitine not only reduced the viability of CD4+ lymphocytes but also suppressed T cell activation and cytokine production. Finally, roscovitine significantly attenuated the severity of T cell-dependent, OX40-enhanced uveitis. Conclusion These results implicate CdK2 in OX40-augmented T cell response and expansion. Furthermore, this study suggests that roscovitine is a novel, promising, therapeutic agent for treating T cell-mediated diseases such as uveitis. PMID:24260551

  10. Effect of chronic microwave radiation on T cell-mediated immunity in the rabbit.

    PubMed

    Nageswari, K S; Sarma, K R; Rajvanshi, V S; Sharan, R; Sharma, M; Barathwal, V; Singh, V

    1991-09-01

    Experiments were conducted to elucidate the effects of chronic low power-level microwave radiation on the immunological systems of rabbits. Fourteen male Belgian white rabbits were exposed to microwave radiation at 5 mW/cm2, 2.1 GHz, 3 h daily, 6 days/week for 3 months in two batches of 7 each in specially designed miniature anechoic chambers. Seven rabbits were subjected to sham exposure for identical duration. The microwave energy was provided through S band standard gain horns connected to a 4K3SJ2 Klystron power amplifier. The first batch of animals were assessed for T lymphocyte-mediated cellular immune response mechanisms and the second batch of animals for B lymphocyte-mediated humoral immune response mechanisms. The peripheral blood samples collected monthly during microwave/sham exposure and during follow-up (5/14 days after termination of exposures, in the second batch animals only) were analysed for T lymphocyte numbers and their mitogen responsiveness to ConA and PHA. Significant suppression of T lymphocyte numbers was noted in the microwave group at 2 months (P less than 0.01, delta % 21.5%) and during follow-up (P less than 0.01, delta % 30.2%). The first batch animals were initially sensitised with BCG and challenged with tuberculin (0.03 ml) at the termination of microwave irradiation/sham exposure and the increase in foot pad thickness (delta mm), which is a measure of T cell-mediated immunity (delayed type hypersensitivity response, DTH) was noted in both the groups. The microwave group revealed a better response than the control group (delta % +12.4 vs. +7.54). The animals were sacrificed and the tissue T lymphocyte counts (spleen and lymph node) were analysed.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1743776

  11. Effect of Chicoric Acid on Mast Cell-Mediated Allergic Inflammation in Vitro and in Vivo.

    PubMed

    Lee, Na Young; Chung, Kyung-Sook; Jin, Jong Sik; Bang, Keuk Soo; Eom, Ye-Jin; Hong, Chul-Hee; Nugroho, Agung; Park, Hee-Jun; An, Hyo-Jin

    2015-12-24

    Chicoric acid (dicaffeoyl-tartaric acid), is a natural phenolic compound found in a number of plants, such as chicory (Cichorium intybus) and Echinacea (Echinacea purpurea), which possesses antioxidant, anti-inflammatory, antiviral, and analgesic activities. Although these biological effects of chicoric acid have been investigated, there are no reports of its antiallergic-related anti-inflammatory effects in human mast cells (HMC)-1 or anaphylactic activity in a mouse model. Therefore, we investigated the antiallergic-related anti-inflammatory effect of chicoric acid and its underlying mechanisms of action using phorbol-12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated HMC-1 cells. Chicoric acid decreased the mRNA expression of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β. We studied the inhibitory effects of chicoric acid on the nuclear translocation of nuclear factor kappa B (NF-κB) and activation of caspase-1. However, mitogen-activated protein kinase (MAPK) activation was not sufficient to abrogate the stimulus. In addition, we investigated the ability of chicoric acid to inhibit compound 48/80-induced systemic anaphylaxis in vivo. Oral administration of chicoric acid at 20 mg/kg inhibited histamine release and protected mice against compound 48/80-induced anaphylactic mortality. These results suggest that chicoric acid has an antiallergic-related anti-inflammatory effect that involves modulating mast cell-mediated allergic responses. Therefore, chicoric acid could be an efficacious agent for allergy-related inflammatory disorders. PMID:26593037

  12. Anti-allergic effects of Lycopus lucidus on mast cell-mediated allergy model

    SciTech Connect

    Shin, Tae-Yong . E-mail: tyshin@woosuk.ac.kr; Kim, Sang-Hyun; Suk, Kyoungho; Ha, Jeoung-Hee; Kim, InKyeom; Lee, Maan-Gee; Jun, Chang-Duk; Kim, Sang-Yong; Lim, Jong-Pil; Eun, Jae-Soon; Shin, Hye-Young; Kim, Hyung-Min

    2005-12-15

    The current study characterizes the mechanism by which the aqueous extract of Lycopus lucidus Turcz. (Labiatae) (LAE) decreases mast cell-mediated immediate-type allergic reaction. The immediate-type allergic reaction is involved in many allergic diseases such as asthma and allergic rhinitis. LAE has been used as a traditional medicine in Korea and is known to have an anti-inflammatory effect. However, its specific mechanism of action is still unknown. LAE was anally administered to mice for high and fast absorption. LAE inhibited compound 48/80-induced systemic reactions in mice. LAE decreased the local allergic reaction, passive cutaneous anaphylaxis, activated by anti-dinitrophenyl (DNP) IgE antibody. LAE dose-dependently reduced histamine release from rat peritoneal mast cells activated by compound 48/80 or anti-DNP IgE. Furthermore, LAE decreased the secretion of TNF-{alpha} and IL-6 in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated human mast cells. The inhibitory effect of LAE on the pro-inflammatory cytokine was p38 mitogen-activated protein kinase (MAPK) and nuclear factor-{kappa}B (NF-{kappa}B) dependent. LAE attenuated PMA plus A23187-induced degradation of I{kappa}B{alpha} and nuclear translocation of NF-{kappa}B, and specifically blocked activation of p38 MAPK, but not that of c-jun N-terminal kinase and extracellular signal-regulated kinase. Our findings provide evidence that LAE inhibits mast cell-derived immediate-type allergic reactions and involvement of pro-inflammatory cytokines, p38 MAPK, and NF-{kappa}B in these effects.

  13. Precision Subtypes of T Cell-Mediated Rejection Identified by Molecular Profiles

    PubMed Central

    Kadota, Paul Ostrom; Hajjiri, Zahraa; Finn, Patricia W.; Perkins, David L.

    2015-01-01

    Among kidney transplant recipients, the treatment of choice for acute T cell-mediated rejection (TCMR) with pulse steroids or antibody protocols has variable outcomes. Some rejection episodes are resistant to an initial steroid pulse, but respond to subsequent antibody protocols. The biological mechanisms causing the different therapeutic responses are not currently understood. Histological examination of the renal allograft is considered the gold standard in the diagnosis of acute rejection. The Banff Classification System was established to standardize the histopathological diagnosis and to direct therapy. Although widely used, it shows variability among pathologists and lacks criteria to guide precision individualized therapy. The analysis of the transcriptome in allograft biopsies, which we analyzed in this study, provides a strategy to develop molecular diagnoses that would have increased diagnostic precision and assist the development of individualized treatment. Our hypothesis is that the histological classification of TCMR contains multiple subtypes of rejection. Using R language algorithms to determine statistical significance, multidimensional scaling, and hierarchical, we analyzed differential gene expression based on microarray data from biopsies classified as TCMR. Next, we identified KEGG functions, protein–protein interaction networks, gene regulatory networks, and predicted therapeutic targets using the integrated database ConsesnsusPathDB (CPDB). Based on our analysis, two distinct clusters of biopsies termed TCMR01 and TCMR02 were identified. Despite having the same Banff classification, we identified 1933 differentially expressed genes between the two clusters. These genes were further divided into three major groups: a core group contained within both the TCMR01 and TCMR02 subtypes, as well as genes unique to TCMR01 or TCMR02. The subtypes of TCMR utilized different biological pathways, different regulatory networks and were predicted to

  14. Cytotoxicity Is Mandatory for CD8+ T Cell–mediated Contact Hypersensitivity

    PubMed Central

    Kehren, Jeanne; Desvignes, Cyril; Krasteva, Maya; Ducluzeau, Marie-Thérèse; Assossou, Olga; Horand, Françoise; Hahne, Michael; Kägi, David; Kaiserlian, Dominique; Nicolas, Jean-François

    1999-01-01

    Contact hypersensitivity (CHS) is a T cell–mediated skin inflammation induced by epicutaneous exposure to haptens in sensitized individuals. We have previously reported that CHS to dinitrofluorobenzene in mice is mediated by major histocompatibility complex (MHC) class I–restricted CD8+ T cells. In this study, we show that CD8+ T cells mediate the skin inflammation through their cytotoxic activity. The contribution of specific cytotoxic T lymphocytes (CTLs) to the CHS reaction was examined both in vivo and in vitro, using mice deficient in perforin and/or Fas/Fas ligand (FasL) pathways involved in cytotoxicity. Mice double deficient in perforin and FasL were able to develop hapten-specific CD8+ T cells in the lymphoid organs but did not show CHS reaction. However, they did not generate hapten-specific CTLs, demonstrating that the CHS reaction is dependent on cytotoxic activity. In contrast, Fas-deficient lpr mice, FasL-deficient gld mice, and perforin-deficient mice developed a normal CHS reaction and were able to generate hapten-specific CTLs, suggesting that CHS requires either the Fas/FasL or the perforin pathway. This was confirmed by in vitro studies showing that the hapten-specific CTL activity was exclusively mediated by MHC class I–restricted CD8+ T cells which could use either the perforin or the Fas/FasL pathway for their lytic activity. Thus, cytotoxic CD8+ T cells, commonly implicated in the host defence against tumors and viral infections, could also mediate harmful delayed-type hypersensitivity reactions. PMID:10049941

  15. The Host Defense Peptide Cathelicidin Is Required for NK Cell-Mediated Suppression of Tumor Growth

    PubMed Central

    Büchau, Amanda S.; Morizane, Shin; Trowbridge, Janet; Schauber, Jürgen; Kotol, Paul; Bui, Jack D.; Gallo, Richard L.

    2010-01-01

    Tumor surveillance requires the interaction of multiple molecules and cells that participate in innate and the adaptive immunity. Cathelicidin was initially identified as an antimicrobial peptide, although it is now clear that it fulfills a variety of immune functions beyond microbial killing. Recent data have suggested contrasting roles for cathelicidin in tumor development. Because its role in tumor surveillance is not well understood, we investigated the requirement of cathelicidin in controlling transplantable tumors in mice. Cathelicidin was observed to be abundant in tumor-infiltrating NK1.1+ cells in mice. The importance of this finding was demonstrated by the fact that cathelicidin knockout mice (Camp−/−) permitted faster tumor growth than wild type controls in two different xenograft tumor mouse models (B16.F10 and RMA-S). Functional in vitro analyses found that NK cells derived from Camp−/− versus wild type mice showed impaired cytotoxic activity toward tumor targets. These findings could not be solely attributed to an observed perforin deficiency in freshly isolated Camp−/− NK cells, because this deficiency could be partially restored by IL-2 treatment, whereas cytotoxic activity was still defective in IL-2-activated Camp−/− NK cells. Thus, we demonstrate a previously unrecognized role of cathelicidin in NK cell antitumor function. PMID:19949065

  16. Multiple low-dose streptozotocin-induced diabetes in the mouse. Evidence for stimulation of a cytotoxic cellular immune response against an insulin-producing beta cell line.

    PubMed Central

    McEvoy, R C; Andersson, J; Sandler, S; Hellerström, C

    1984-01-01

    Mice were examined for the presence of splenocytes specifically cytotoxic for a rat insulinoma cell line (RIN) during the induction of diabetes by streptozotocin (SZ) in multiple low doses (Multi-Strep). Cytotoxicity was quantitated by the release of 51Cr from damaged cells. A low but statistically significant level of cytolysis (5%) by splenocytes was first detectable on day 8 after the first dose of SZ. The cytotoxicity reached a maximum of approximately 9% on day 10 and slowly decreased thereafter, becoming undetectable 42 d after SZ was first given. The time course of the in vitro cytotoxic response correlated with the degree of insulitis demonstrable in the pancreata of the Multi-Strep mice. The degree of cytotoxicity after Multi-Strep was related to the number of effector splenocytes to which the target RIN cells were exposed and was comparable to that detectable after immunization by intraperitoneal injection of RIN cells in normal mice. The cytotoxicity was specific for insulin-producing cells; syngeneic, allogeneic, and xenogeneic lymphocytes and lymphoblasts, 3T3 cells, and a human keratinocyte cell line were not specifically lysed by the splenocytes of the Multi-Strep mice. This phenomenon was limited to the Multi-Strep mice. Splenocytes from mice made diabetic by a single, high dose of SZ exhibited a very low level of cytotoxicity against the RIN cells. The cytotoxic response was also quantitated in splenocytes from control and Multi-Strep mice (10 d after the first dose of SZ) before and after culture with mitomycin-treated RIN cells in the presence of T cell growth factor (TCGF). The cytotoxicity of the Multi-Strep splenocytes was enhanced more than fivefold after such culture, suggesting the proliferation of an effector cell that could be stimulated and supported in vitro by TCGF. These results support the hypothesis that cell-mediated anti-beta cell autoimmunity may play a role in the destruction of the beta cells in this animal model. The

  17. CDK8-Mediated STAT1-S727 Phosphorylation Restrains NK Cell Cytotoxicity and Tumor Surveillance

    PubMed Central

    Putz, Eva Maria; Gotthardt, Dagmar; Hoermann, Gregor; Csiszar, Agnes; Wirth, Silvia; Berger, Angelika; Straka, Elisabeth; Rigler, Doris; Wallner, Barbara; Jamieson, Amanda M.; Pickl, Winfried F.; Zebedin-Brandl, Eva Maria; Müller, Mathias; Decker, Thomas; Sexl, Veronika

    2013-01-01

    Summary The transcription factor STAT1 is important in natural killer (NK) cells, which provide immediate defense against tumor and virally infected cells. We show that mutation of a single phosphorylation site (Stat1-S727A) enhances NK cell cytotoxicity against a range of tumor cells, accompanied by increased expression of perforin and granzyme B. Stat1-S727A mice display significantly delayed disease onset in NK cell-surveilled tumor models including melanoma, leukemia, and metastasizing breast cancer. Constitutive phosphorylation of S727 depends on cyclin-dependent kinase 8 (CDK8). Inhibition of CDK8-mediated STAT1-S727 phosphorylation may thus represent a therapeutic strategy for stimulating NK cell-mediated tumor surveillance. PMID:23933255

  18. Cytotoxic T lymphocytes as a potential brake of keratinocyte proliferation in psoriasis.

    PubMed

    Vičić, Marijana; Peternel, Sandra; Simonić, Edita; Sotošek-Tokmadžić, Vlatka; Massari, Dražen; Brajac, Ines; Kaštelan, Marija; Prpić-Massari, Larisa

    2016-02-01

    Psoriasis is a chronic papulosquamous skin disease, histologically characterized by epidermal hyperproliferation and dermal infiltration of inflammatory cells. The majority of T lymphocytes infiltrating dermis are CD4+ T lymphocytes secreting type 1 and type 17 cytokines. These cytokines are responsible for triggering keratinocyte proliferation as well as chemokine secretion and subsequent migration of other inflammatory cells in the skin. Contrarily, lymphocytes that accumulate in epidermis are mainly CD8+ T lymphocytes. According to the recent findings, these cells can also secrete type 1 and type 17 cytokines. However, it is demonstrated so far that epidermal CD8+ T lymphocytes contain higher amounts of cytolytic molecules, such as perforin, granzyme B and granulysin whose role in psoriasis pathogenesis is still unknown. Therefore, in this article we hypothesize the active involvement of cell mediated cytotoxicity in killing the proliferating keratinocytes as a mechanism of potential self-defense and possible brake in psoriatic plaque formation, maintaining skin homeostasis. PMID:26826643

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed

    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

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

    NASA Technical Reports Server (NTRS)

    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.

  2. Vα24-invariant NKT cells mediate antitumor activity via killing of tumor-associated macrophages

    PubMed Central

    Song, Liping; Asgharzadeh, Shahab; Salo, Jill; Engell, Kelly; Wu, Hong-wei; Sposto, Richard; Ara, Tasnim; Silverman, Ayaka M.; DeClerck, Yves A.; Seeger, Robert C.; Metelitsa, Leonid S.

    2009-01-01

    Tumor infiltration with Vα24-invariant NKT cells (NKTs) associates with favorable outcome in neuroblastoma and other cancers. Although NKTs can be directly cytotoxic against CD1d+ cells, the majority of human tumors are CD1d–. Therefore, the role of NKTs in cancer remains largely unknown. Here, we demonstrate that CD68+ tumor-associated monocytes/macrophages (TAMs) represented the majority of CD1d-expressing cells in primary human neuroblastomas. TAMs stimulated neuroblastoma growth in human cell lines and their xenografts in NOD/SCID mice via IL-6 production. Indeed, TAMs produced IL-6 in primary tumors and in the BM of patients with metastatic neuroblastoma. Gene expression analysis using TaqMan low-density arrays of 129 primary human neuroblastomas without MYCN amplification revealed that high-level expression of TAM-specific genes (CD14, CD16, IL6, IL6R, and TGFB1) was associated with poor 5-year event-free survival. While NKTs were not cytotoxic against neuroblastoma cells, they effectively killed monocytes pulsed with tumor cell lysate. The killing of monocytes was CD1d restricted because it was inhibited by a CD1d-specific mAb. Cotransfer of human monocytes and NKTs to tumor-bearing NOD/SCID mice decreased monocyte number at the tumor site and suppressed tumor growth compared with mice transferred with monocytes alone. Thus, killing of TAMs reveals what we believe to be a novel mechanism of NKT antitumor activity that relates to the disease outcome. PMID:19411762

  3. Saponins as cytotoxic agents: a review

    PubMed Central

    Galanty, Agnieszka; Sobolewska, Danuta

    2010-01-01

    Saponins are natural glycosides which possess a wide range of pharmacological properties including cytotoxic activity. In this review, the recent studies (2005–2009) concerning the cytotoxic activity of saponins have been summarized. The correlations between the structure and the cytotoxicity of both steroid and triterpenoid saponins have been described as well as the most common mechanisms of action. PMID:20835386

  4. Cell-mediated and humoral immune responses in pigs following primary and challenge-exposure to Lawsonia intracellularis

    PubMed Central

    2012-01-01

    To investigate immune responses upon re-infection with Lawsonia intracellularis, local and peripheral humoral and cell-mediated immune responses to primary and challenge inoculations were studied in 22 pigs. Pigs were orally inoculated with virulent L. intracellularis at the age of 5-6 weeks, treated with antibiotics and challenged with a re-inoculation (RE) at the age of 12 weeks. Treatment control (TC) pigs received only the primary inoculation and challenge control (CC) pigs received only the secondary inoculation at 12 weeks of age. Following this regimen, all RE pigs were protected against the re-infection as defined by reduced colonisation and pathology of intestinal mucosa, absence of bacterial shedding and without increase in serum acute phase protein response. In the protected RE pigs, serum IgG responses were variable with both high and low responders. Serum IgA responses were not boosted by the re-inoculation, since identical intestinal IgA responses developed in response to the inoculation in both the susceptible CC pigs and the protected RE pigs. A memory recall cell-mediated immune response developed in RE pigs which was significantly stronger compared to the primary response in age-matched CC pigs as assessed by whole blood IFN-γ assay and by calculation of IFN-γ integrated median fluorescence intensity (iMFI) after flow cytometry. The major IFN-γ producing cells were identified as CD8+ and CD4+CD8+ double positive lymphocytes. The results indicate that cell-mediated immune responses are likely mediators of protective immunity against L. intracellularis, with CD8+ effector cells and CD4+CD8+ double positive memory T cells as main contributors to the antigen-specific IFN-γ production. PMID:22316065

  5. Cell-mediated and humoral immune responses in pigs following primary and challenge-exposure to Lawsonia intracellularis.

    PubMed

    Cordes, Henriette; Riber, Ulla; Jensen, Tim K; Jungersen, Gregers

    2012-01-01

    To investigate immune responses upon re-infection with Lawsonia intracellularis, local and peripheral humoral and cell-mediated immune responses to primary and challenge inoculations were studied in 22 pigs. Pigs were orally inoculated with virulent L. intracellularis at the age of 5-6 weeks, treated with antibiotics and challenged with a re-inoculation (RE) at the age of 12 weeks. Treatment control (TC) pigs received only the primary inoculation and challenge control (CC) pigs received only the secondary inoculation at 12 weeks of age. Following this regimen, all RE pigs were protected against the re-infection as defined by reduced colonisation and pathology of intestinal mucosa, absence of bacterial shedding and without increase in serum acute phase protein response. In the protected RE pigs, serum IgG responses were variable with both high and low responders. Serum IgA responses were not boosted by the re-inoculation, since identical intestinal IgA responses developed in response to the inoculation in both the susceptible CC pigs and the protected RE pigs. A memory recall cell-mediated immune response developed in RE pigs which was significantly stronger compared to the primary response in age-matched CC pigs as assessed by whole blood IFN-γ assay and by calculation of IFN-γ integrated median fluorescence intensity (iMFI) after flow cytometry. The major IFN-γ producing cells were identified as CD8+ and CD4+CD8+ double positive lymphocytes. The results indicate that cell-mediated immune responses are likely mediators of protective immunity against L. intracellularis, with CD8+ effector cells and CD4+CD8+ double positive memory T cells as main contributors to the antigen-specific IFN-γ production. PMID:22316065

  6. The role of T-cell-mediated mechanisms in virus infections of the nervous system.

    PubMed

    Dörries, R

    2001-01-01

    during or shortly after exerting their effector functions. The clinical consequences and the influence of the effector phase on the further course of the infection depends on the balance and fine-tuning of the contributing lymphoid cell populations. Generally, any delay in the recruitment of effector lymphocytes to the tissue or an unbalanced combination of lymphocyte subsets allows the virus to spread in the CNS, which in turn will cause severe immune-mediated tissue effects as well as disease. If either too late or partially deficient, the immune system response may contribute to a lethal outcome or cause autosensitization to brain-specific antigens by epitope spreading to the antigen-presenting system in peripheral lymphoid tissue. This could form the basis for subsequent booster reactions of autosensitized CD4+ T cells--a process that finally will end in an inflammatory autoimmune reaction, which in humans we call multiple sclerosis. In contrast, a rapid and specific local response in the brain tissue will result in efficient limitation of viral spread and thereby a subclinical immune system-mediated termination of the infection. After clearance of virus-infected cells, downsizing of the local response probably occurs via self-elimination of the contributing T cell populations and/or by so far unidentified signal pathways. However, much of this is highly speculative, and more data have to be collected to make decisive conclusions regarding this matter. Several strategies have been developed by viruses to escape T cell-mediated eradication, including interference with the MHC class I presentation pathway of the host cell or "hiding" in cells which lack MHC class I expression. This may result in life-long persistence of the virus in the brain, a state which probably is actively controlled by T lymphocytes. Under severe immunosuppression, however, reactivation of viral replication can occur, which is a lethal threat to the host. PMID:11417137

  7. Overrepresentation of IL-10-Expressing B Cells Suppresses Cytotoxic CD4+ T Cell Activity in HBV-Induced Hepatocellular Carcinoma

    PubMed Central

    Tan, Hongwu; Zhu, Zun-Qiang; Zhang, Zhang-Yun; Zhao, Ludong

    2016-01-01

    Hepatocellular carcinoma (HCC) is a common cancer with poor prognosis and low five-year survival rate. A strong and effective CD4+ T cell-mediated cytotoxicity was associated with better survival and low recurrence rate in HCC, but the regulatory mechanism that controls CD4+ T cell cytotoxicity in HCC patients is not fully examined. Given that IL-10-expressing B cells could suppress the inflammation of cytotoxic CD8+ T cells, T helper 1 (Th1) cells and Th17 cells, while promoting regulatory T (Treg) cell differentiation, we examined the role of IL-10-expressing B cells in HBV-related HCC patients. We found that compared to healthy controls, HCC patients exhibited significantly higher frequencies of IL-10-expressing B cells, which were negatively correlated with the frequencies of granzyme A, granzyme B, and perforin expressing CD4+ T cells. Surface molecule Tim-1 was preferentially expressed on IL-10-expressing B cells. Therefore, we separated total B cells into Tim-1+ and Tim-1- B cells. CD4+ T cells incubated with Tim-1+ B cells exhibited significantly reduced levels of granzyme A, granzyme B and perforin expression, compared to the CD4+ T cells incubated with Tim-1- B cells. Antagonizing IL-10 in culture rescued CD4+ T cell cytotoxicity. Compared to that in peripheral blood, the level of IL-10-expressing B cells were further upregulated in resected tumor, while the level of CD4+ cytotoxic T cells was downregulated. The negative correlations between IL-10-expressing B cells and CD4+ cytotoxic T cells were also observed in tumor-infiltrating cells. Together, our data revealed an additional antitumor mechanism mediated by IL-10-expressing B cells. PMID:27136203

  8. Overrepresentation of IL-10-Expressing B Cells Suppresses Cytotoxic CD4+ T Cell Activity in HBV-Induced Hepatocellular Carcinoma.

    PubMed

    Xue, Hongwei; Lin, Fuhuang; Tan, Hongwu; Zhu, Zun-Qiang; Zhang, Zhang-Yun; Zhao, Ludong

    2016-01-01

    Hepatocellular carcinoma (HCC) is a common cancer with poor prognosis and low five-year survival rate. A strong and effective CD4+ T cell-mediated cytotoxicity was associated with better survival and low recurrence rate in HCC, but the regulatory mechanism that controls CD4+ T cell cytotoxicity in HCC patients is not fully examined. Given that IL-10-expressing B cells could suppress the inflammation of cytotoxic CD8+ T cells, T helper 1 (Th1) cells and Th17 cells, while promoting regulatory T (Treg) cell differentiation, we examined the role of IL-10-expressing B cells in HBV-related HCC patients. We found that compared to healthy controls, HCC patients exhibited significantly higher frequencies of IL-10-expressing B cells, which were negatively correlated with the frequencies of granzyme A, granzyme B, and perforin expressing CD4+ T cells. Surface molecule Tim-1 was preferentially expressed on IL-10-expressing B cells. Therefore, we separated total B cells into Tim-1+ and Tim-1- B cells. CD4+ T cells incubated with Tim-1+ B cells exhibited significantly reduced levels of granzyme A, granzyme B and perforin expression, compared to the CD4+ T cells incubated with Tim-1- B cells. Antagonizing IL-10 in culture rescued CD4+ T cell cytotoxicity. Compared to that in peripheral blood, the level of IL-10-expressing B cells were further upregulated in resected tumor, while the level of CD4+ cytotoxic T cells was downregulated. The negative correlations between IL-10-expressing B cells and CD4+ cytotoxic T cells were also observed in tumor-infiltrating cells. Together, our data revealed an additional antitumor mechanism mediated by IL-10-expressing B cells. PMID:27136203

  9. Frequency of Cytotoxic T Lymphocyte Precursors to Herpes Simplex Virus Type 1 as Determined by Limiting Dilution Analysis

    PubMed Central

    Rouse, Barry T.; Larsen, Hal S.; Wagner, Hermann

    1983-01-01

    The conditions for establishing a limiting dilution assay to measure cytotoxic T lymphocyte precursors (CTL-P) against herpes simplex virus type 1 (HSV-1) were determined. Analysis by Poisson statistics demonstrated that the estimated frequency of HSV-1-reactive cells in the spleens of normal mice was less than 1/250,000. In contrast, mice immunized previously with infectious HSV-1 demonstrated a CTL-P frequency between 1/3,500 and 1/15,670. The generation of a maximum cytotoxic T lymphocyte response required that mice be primed in vivo with infectious virus. Immunization with inactivated virus either failed to elicit detectable CTL-P frequencies or gave frequencies markedly less than those induced with infectious virus. To obtain positive cultures, the responder cell population had to be exposed to stimulator splenocytes expressing viral antigens. Normal splenocytes without virus or normal splenocytes with T cell growth factor did not result in significant cytotoxicity. Split culture analysis comparing cytotoxicity against syngeneic and allogeneic virus-infected targets provided evidence for specificity, H-2 restriction, and the T cell nature of the CTL-P. It was determined that precursors were eliminated by treatment with anti-Thy 1, Lyt 2.1, or Lyt 1.1, indicating the CTL-P were Lyt 1+2+ cells. Cytotoxicity was reduced after treatment of the responders with anti-Lyt 2 plus complement, which gave further evidence of the T cell nature of the cytotoxic T lymphocytes. These experiments demonstrated the feasibility of using the limiting dilution approach as a highly sensitive and quantitative means to measure the cell-mediated immune response to HSV-1 antigens. PMID:6299949

  10. Comparative immunotoxicity of 2,2`-dichlorodiethyl sulfide and cyclophosphamide: Evaluation of L1210 tumor cell resistance, cell-mediated immunity, and humoral immunity. (Reannouncement with new availability information)

    SciTech Connect

    Blank, J.A.; Joiner, R.L.; Houchens, D.P.; Dill, G.S.; Hobson, D.W.

    1991-12-31

    The immunotoxicity of 2,2`-dichlorodiethyl sulfide (sulfur mustard, SM),on humoral and cell-mediated immunity was compared with that of the nitrogen mustard 2-(bis(2-chloroethyl) amino)tetrahydro- 2H-1,3,2-oxazophosphorine 2-oxide (cyclophosphamide, CP). SM and CP had similar effects on thymic and splenic weights, spleen cell number, and the formation of antibody producing cells to sheep red blood cells (sRBC) when examined 5 days after exposure, but differed in their effects on body weights. Although there were no differences in the delayed hypersensitivity response to keyhole limpet hemocyanin, CP and SM had different effects in the L1210 tumor cell allograft rejection assay. CP, but not SM, decreased the 28 day survival rate of allogeneic mice exposed to a sublethal L1210 tumor challenge. The differing effects on survival to the L1210 tumor challenge could not be attributed to a direct cytotoxic effect of SM on the L1210 tumor cells as SM did not increase the survival rate or mediansurvival time of syngeneic mice exposed to a lethal L1210 tumor cell challenge. In summary, SM and CP had immunosuppressive effects in the humoral immune assay. Although neither compound suppressed the delayed hypersensitivity response, CP was found to suppress host resistance to L1210 tumor cells.

  11. MHC-I non-restricted cytotoxic activity in Macaca sylvana experimentally inoculated with HIV2 and SIV/mac.

    PubMed

    Charaf, B; Sanhadji, K; Sekkat, S; Farouqui, B; Touraine, J L; Benslimane, A

    1993-08-01

    The anti-retrovirus cell-mediated immunity was repeatedly investigated in seven monkeys (Macaca sylvana). Four of these animals were injected with cell-free supernatants containing human immunodeficiency viruses: two monkeys received HIV1 Bru (2.5 x 10(6) cpm), two received HIV2 Rod (1.5 x 10(6) cpm). Two additional animals were injected with a cell-free supernatant containing simian immunodeficiency virus SIV/mac 251 (1.5 x 10(6) cpm) and the last animal served as control. The four macaques infected with HIV2 Rod and SIV/mac 251 seroconverted. Freshly isolated and non stimulated peripheral blood mononuclear cells from these infected macaques and from the uninfected control were repeatedly assessed for cytolytic activity. Target cells consisted of heterologous human cell lines expressing HIV1 Bru, HIV2 Rod or SIV/mac proteins. A significant cytotoxic activity, non-restricted at the major histocompatibility complex class I (MHC-I), was demonstrated in one HIV2 Rod-infected animal (F8) and in one SIV/mac 251-infected animal (M1). This last animal showed progressively diminishing cytolytic activity that was correlated with a pronounced decrease in CD4+ lymphocytes. An AIDS-like disease developed in M1, with presence of lymphadenopathy, weight loss, diarrhea and opportunistic infections. Cytotoxic activity was active against SIV and HIV2-infected target cells in an MHC-unrestricted manner; it was specific to virus-infected cells and there was cross-reactivity between HIV2 and SIV. Cytotoxic effectors appeared to be mainly CD8+ cells. This model may prove to be very useful in evaluating the capacity of candidate AIDS vaccines to elicit effective cell-mediated immune responses. PMID:7905683

  12. Stromal cell-mediated mitochondrial redox adaptation regulates drug resistance in childhood acute lymphoblastic leukemia

    PubMed Central

    Liu, Jizhong; Masurekar, Ashish; Johnson, Suzanne; Chakraborty, Sohini; Griffiths, John; Smith, Duncan; Alexander, Seema; Dempsey, Clare; Parker, Catriona; Harrison, Stephanie; Li, Yaoyong; Miller, Crispin; Di, Yujun; Ghosh, Zhumur; Krishnan, Shekhar; Saha, Vaskar

    2015-01-01

    Despite the high cure rates in childhood acute lymphoblastic leukemia (ALL), relapsed ALL remains a significant clinical problem. Genetic heterogeneity does not adequately explain variations in response to therapy. The chemoprotective tumor microenvironment may additionally contribute to disease recurrence. This study identifies metabolic reprogramming of leukemic cells by bone marrow stromal cells (BMSC) as a putative mechanism of drug resistance. In a BMSC-extracellular matrix culture model, BMSC produced chemoprotective soluble factors and facilitated the emergence of a reversible multidrug resistant phenotype in ALL cells. BMSC environment induced a mitochondrial calcium influx leading to increased reactive oxygen species (ROS) levels in ALL cells. In response to this oxidative stress, drug resistant cells underwent a redox adaptation process, characterized by a decrease in ROS levels and mitochondrial membrane potential with an upregulation of antioxidant production and MCL-1 expression. Similar expanded subpopulations of low ROS expressing and drug resistant cells were identified in pre-treatment bone marrow samples from ALL patients with slower response to therapy. This suggests that the bone marrow microenvironment induces a redox adaptation in ALL subclones that protects against cytotoxic stress and potentially gives rise to minimal residual disease. Targeting metabolic remodeling by inhibiting antioxidant production and antiapoptosis was able to overcome drug resistance. Thus metabolic plasticity in leukemic cell response to environmental factors contributes to chemoresistance and disease recurrence. Adjunctive strategies targeting such processes have the potential to overcome therapeutic failure in ALL. PMID:26474278

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

    PubMed Central

    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

  14. NK Cells and γδ T Cells Mediate Resistance to Polyomavirus–Induced Tumors

    PubMed Central

    Mishra, Rabinarayan; Chen, Alex T.; Welsh, Raymond M.; Szomolanyi-Tsuda, Eva

    2010-01-01

    NK and γδ T cells can eliminate tumor cells in many experimental models, but their effect on the development of tumors caused by virus infections in vivo is not known. Polyomavirus (PyV) induces tumors in neonatally infected mice of susceptible strains and in adult mice with certain immune deficiencies, and CD8+ αβ T cells are regarded as the main effectors in anti-tumor immunity. Here we report that adult TCRβ knockout (KO) mice that lack αβ but have γδ T cells remain tumor-free after PyV infection, whereas TCRβ×δ KO mice that lack all T cells develop tumors. In addition, E26 mice, which lack NK and T cells, develop the tumors earlier than TCRβ×δ KO mice. These observations implicate γδ T and NK cells in the resistance to PyV-induced tumors. Cell lines established from PyV-induced tumors activate NK and γδ T cells both in culture and in vivo and express Rae-1, an NKG2D ligand. Moreover, these PyV tumor cells are killed by NK cells in vitro, and this cytotoxicity is prevented by treatment with NKG2D-blocking antibodies. Our findings demonstrate a protective role for NK and γδ T cells against naturally occurring virus-induced tumors and suggest the involvement of NKG2D-mediated mechanisms. PMID:20523894

  15. Modulation by gamma interferon of antiviral cell-mediated immune responses in vivo.

    PubMed Central

    Utermöhlen, O; Dangel, A; Tárnok, A; Lehmann-Grube, F

    1996-01-01

    Mice were infected with lymphocytic choriomeningitis virus and injected once 24 h later with a monoclonal antibody directed against gamma interferon. In comparison with controls, the increase of numbers of CD8+ T cells and the generation of virus-specific cytotoxic T lymphocytes in spleens and virus clearance from organs were diminished, as was the ability of spleen cells to transmit adoptive immunity to infected recipients. The same treatment slightly but consistently lessened rather than augmented the virus titers early in infection, which was also observed in thymusless nu/nu mice. Injection into infected mice of the lymphokine itself in quantities probably higher than are produced endogenously resulted in lower virus titers in spleens but higher titers in livers. The adoptive immunity in infected mice achieved by infusion of immune spleen cells was not altered by treating the recipients with gamma interferon monoclonal antibody. Such treatment did not measurably affect the production of antiviral serum antibodies. We conclude that in lymphocytic choriomeningitis virus-infected mice, gamma interferon is needed for the generation of antivirally active CD8+ T lymphocytes, and furthermore that in this experimental model, direct antiviral effects of the lymphokine elude detection. PMID:8627670

  16. Stromal cell-mediated mitochondrial redox adaptation regulates drug resistance in childhood acute lymphoblastic leukemia.

    PubMed

    Liu, Jizhong; Masurekar, Ashish; Johnson, Suzanne; Chakraborty, Sohini; Griffiths, John; Smith, Duncan; Alexander, Seema; Dempsey, Clare; Parker, Catriona; Harrison, Stephanie; Li, Yaoyong; Miller, Crispin; Di, Yujun; Ghosh, Zhumur; Krishnan, Shekhar; Saha, Vaskar

    2015-12-15

    Despite the high cure rates in childhood acute lymphoblastic leukemia (ALL), relapsed ALL remains a significant clinical problem. Genetic heterogeneity does not adequately explain variations in response to therapy. The chemoprotective tumor microenvironment may additionally contribute to disease recurrence. This study identifies metabolic reprogramming of leukemic cells by bone marrow stromal cells (BMSC) as a putative mechanism of drug resistance. In a BMSC-extracellular matrix culture model, BMSC produced chemoprotective soluble factors and facilitated the emergence of a reversible multidrug resistant phenotype in ALL cells. BMSC environment induced a mitochondrial calcium influx leading to increased reactive oxygen species (ROS) levels in ALL cells. In response to this oxidative stress, drug resistant cells underwent a redox adaptation process, characterized by a decrease in ROS levels and mitochondrial membrane potential with an upregulation of antioxidant production and MCL-1 expression. Similar expanded subpopulations of low ROS expressing and drug resistant cells were identified in pre-treatment bone marrow samples from ALL patients with slower response to therapy. This suggests that the bone marrow microenvironment induces a redox adaptation in ALL subclones that protects against cytotoxic stress and potentially gives rise to minimal residual disease. Targeting metabolic remodeling by inhibiting antioxidant production and antiapoptosis was able to overcome drug resistance. Thus metabolic plasticity in leukemic cell response to environmental factors contributes to chemoresistance and disease recurrence. Adjunctive strategies targeting such processes have the potential to overcome therapeutic failure in ALL. PMID:26474278

  17. Dendritic cell based immunotherapy using tumor stem cells mediates potent antitumor immune responses.

    PubMed

    Dashti, Amir; Ebrahimi, Marzieh; Hadjati, Jamshid; Memarnejadian, Arash; Moazzeni, Seyed Mohammad

    2016-04-28

    Cancer stem cells (CSCs) are demonstrated to be usually less sensitive to conventional methods of cancer therapies, resulting in tumor relapse. It is well-known that an ideal treatment would be able to selectively target and kill CSCs, so as to avoid the tumor reversion. The aim of our present study was to evaluate the effectiveness of a dendritic cell (DC) based vaccine against CSCs in a mouse model of malignant melanoma. C57BL/6 mouse bone marrow derived DCs pulsed with a murine melanoma cell line (B16F10) or CSC lysates were used as a vaccine. Immunization of mice with CSC lysate-pulsed DCs was able to induce a significant prophylactic effect by a higher increase in lifespan and obvious depression of tumor growth in tumor bearing mice. The mice vaccinated with DCs loaded with CSC-lysate were revealed to produce specific cytotoxic responses to CSCs. The proliferation assay and cytokine (IFN-γ and IL-4) secretion of mice vaccinated with CSC lysate-pulsed DCs also showed more favorable results, when compared to those receiving B16F10 lysate-pulsed DCs. These findings suggest a potential strategy to improve the efficacy of DC-based immunotherapy of cancers. PMID:26803056

  18. Plasmodium berghei: immunosuppression of the cell-mediated immune response induced by nonviable antigenic preparations

    SciTech Connect

    Gross, A.; Frankenburg, S.

    1989-01-01

    In this work, plasmodial antigens were examined for their ability to suppress the cellular immune response during lethal Plasmodium berghei infection. Splenic enlargement and the number and function of white spleen cells were assessed after injection of normal mice with irradiated parasitized erythrocytes (IPE) or with parasitized erythrocytes (PE) membranes. Both IPE and PE membranes caused splenomegaly and an increase in the number of splenic white cells with concurrent alteration of the relative proportions of T cells and macrophages. The percentage of T lymphocytes was fractionally diminished, but there was a marked increase in Lyt 2.2 positive (suppressor and cytotoxic) T subsets and in the number of splenic macrophage precursors. The pathological enlargement of the spleen was induced by various plasma membrane-derived antigens containing both proteins and carbohydrates. Splenocytes of mice injected with liposomes containing deoxycholate-treated PE or PE fractions showed both diminished interleukin 2 production and a decreased response to mitogen. It appears that some of the changes in the cellular immune response during P. berghei infection are a consequence of the massive provision of a wide spectrum of antigens, capable of suppressing the immune response. Thus, it may be appropriate to evaluate the possible negative effect of parasite epitopes that are candidates for vaccine.

  19. Cytotoxic geranylflavonoids from Bonannia graeca

    PubMed Central

    Rosselli, Sergio; Bruno, Maurizio; Maggio, Antonella; Raccuglia, Rosa Angela; Safder, Muhammad; Lai, Chin-Yu; Bastow, Kenneth F.; Lee, Kuo-Hsiung

    2011-01-01

    The analysis of the aerial parts of Bonannia graeca led to the isolation and characterization of two new polar geranylated flavonoids (6 and 7). The structure elucidation was performed by extensive spectroscopic methods (1D and 2D NMR) and comparison with literature data. All natural flavonoids isolated from B. graeca (1–7) and some synthetic derivatives (8–11) were tested for cytotoxic activity against four human tumor cell lines. Preliminary structure-activity relationship correlations are discussed. PMID:21459391

  20. Cytotoxic diterpenes from Scoparia dulcis.

    PubMed

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

    2003-07-01

    Four new labdane-derived diterpenes, iso-dulcinol (1), 4-epi-scopadulcic acid B (2), dulcidiol (4), and scopanolal (5), together with two known diterpenes, dulcinol/scopadulciol (3) and scopadiol (6), were isolated from the aerial parts of Scoparia dulcis. The structures were determined by extensive NMR studies. The crude extracts as well as the pure diterpenes showed cytotoxicity against a panel of six human stomach cancer cell lines. PMID:12880314

  1. Cytotoxic Compounds from Brucea mollis

    PubMed Central

    Tung, Mai Hung Thanh; Đuc, Ho Viet; Huong, Tran Thu; Duong, Nguyen Thanh; Phuong, Do Thi; Thao, Do Thi; Tai, Bui Huu; Kim, Young Ho; Bach, Tran The; Cuong, Nguyen Manh

    2013-01-01

    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. PMID:24106661

  2. Cytotoxic effects of aggregated nanomaterials.

    PubMed

    Soto, Karla; Garza, K M; Murr, L E

    2007-05-01

    This study deals with cytotoxicity assays performed on an array of commercially manufactured inorganic nanoparticulate materials, including Ag, TiO(2), Fe(2)O(3), Al(2)O(3), ZrO(2), Si(3)N(4), naturally occurring mineral chrysotile asbestos and carbonaceous nanoparticulate materials such as multiwall carbon nanotube aggregates and black carbon aggregates. The nanomaterials were characterized by TEM, as the primary particles, aggregates or long fiber dimensions ranged from 2nm to 20microm. Cytotoxicological assays of these nanomaterials were performed utilizing a murine alveolar macrophage cell line and human macrophage and epithelial lung cell lines as comparators. The nanoparticulate materials exhibited varying degrees of cytoxicity for all cell lines and the general trends were similar for both the murine and human macrophage cell lines. These findings suggest that representative cytotoxic responses for humans might be obtained by nanoparticulate exposures to simple murine macrophage cell line assays. Moreover, these results illustrate the utility in performing rapid in vitro assays for cytotoxicity assessments of nanoparticulate materials as a general inquiry of potential respiratory health risks in humans. PMID:17275430

  3. Mosla dianthera inhibits mast cell-mediated allergic reactions through the inhibition of histamine release and inflammatory cytokine production

    SciTech Connect

    Lee, Dong-Hee; Kim, Sang-Hyun . E-mail: shkim72@knu.ac.kr; Eun, Jae-Soon; Shin, Tae-Yong . E-mail: tyshin@woosuk.ac.kr

    2006-11-01

    In this study, we investigated the effect of the aqueous extract of Mosla dianthera (Maxim.) (AEMD) on the mast cell-mediated allergy model and studied the possible mechanism of action. Mast cell-mediated allergic disease is involved in many diseases such as asthma, sinusitis and rheumatoid arthritis. The discovery of drugs for the treatment of allergic disease is an important subject in human health. AEMD inhibited compound 48/80-induced systemic reactions in mice. AEMD decreased immunoglobulin E-mediated local allergic reactions, passive cutaneous anaphylaxis. AEMD attenuated intracellular calcium level and release of histamine from rat peritoneal mast cells activated by compound 48/80. Furthermore, AEMD attenuated the phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187-stimulated TNF-{alpha}, IL-8 and IL-6 secretion in human mast cells. The inhibitory effect of AEMD on the pro-inflammatory cytokines was nuclear factor-{kappa}B (NF-{kappa}B) dependent. AEMD decreased PMA and A23187-induced degradation of I{kappa}B{alpha} and nuclear translocation of NF-{kappa}B. Our findings provide evidence that AEMD inhibits mast cell-derived immediate-type allergic reactions and involvement of pro-inflammatory cytokines and NF-{kappa}B in these effects.

  4. Comparison of the effectiveness of antibody and cell-mediated immunity against inhaled and instilled influenza virus challenge

    PubMed Central

    2013-01-01

    Background To evaluate immunity against influenza, mouse challenge studies are typically performed by intranasal instillation of a virus suspension to anesthetized animals. This results in an unnatural environment in the lower respiratory tract during infection, and therefore there is some concern that immune mechanisms identified in this model may not reflect those that protect against infectious virus particles delivered directly to the lower respiratory tract as an aerosol. Method To evaluate differences in protection against instilled and inhaled virus, mice were immunized with influenza antigens known to induce antibody or cell-mediated responses and then challenged with 100 LD50 A/PR/8/34 (PR8) in the form of aerosol (inhaled) or liquid suspension (instilled). Results Mice immunized with recombinant adenovirus (Ad) expressing hemagglutinin were protected against weight loss and death in both challenge models, however immunization with Ad expressing nucleoprotein of influenza A (NPA) or M2 resulted in greater protection against inhaled aerosolized virus than virus instilled in liquid suspension. Ad-M2, but not Ad-NPA-immunized mice were protected against a lower instillation challenge dose. Conclusions These results demonstrate differences in protection that are dependent on challenge method, and suggest that cell-mediated immunity may be more accurately demonstrated in mouse inhalation studies. Furthermore, the data suggest immune mechanisms generally characterized as incomplete or weak in mouse models using liquid intranasal challenge may offer greater immunity against influenza infection than previously thought. PMID:23777453

  5. Regulation of NKT cell-mediated immune responses to tumours and liver inflammation by mitochondrial PGAM5-Drp1 signalling

    PubMed Central

    Kang, Young Jun; Bang, Bo-Ram; Han, Kyung Ho; Hong, Lixin; Shim, Eun-Jin; Ma, Jianhui; Lerner, Richard A.; Otsuka, Motoyuki

    2015-01-01

    The receptor-interacting protein kinase 3 (RIPK3) plays crucial roles in programmed necrosis and innate inflammatory responses. However, a little is known about the involvement of RIPK3 in NKT cell-mediated immune responses. Here, we demonstrate that RIPK3 plays an essential role in NKT cell function via activation of the mitochondrial phosphatase phosphoglycerate mutase 5 (PGAM5). RIPK3-mediated activation of PGAM5 promotes the expression of cytokines by facilitating nuclear translocation of NFAT and dephosphorylation of dynamin-related protein 1 (Drp1), a GTPase is essential for mitochondrial homoeostasis. Ripk3−/− mice show reduced NKT cell responses to metastatic tumour cells, and both deletion of RIPK3 and pharmacological inhibition of Drp1 protects mice from NKT cell-mediated induction of acute liver damage. Collectively, the results identify a crucial role for RIPK3-PGAM5-Drp1/NFAT signalling in NKT cell activation, and further suggest that RIPK3-PGAM5 signalling may mediate crosstalk between mitochondrial function and immune signalling. PMID:26381214

  6. TRAF3 is required for T cell-mediated immunity and T cell receptor/CD28 signaling1

    PubMed Central

    Xie, Ping; Kraus, Zachary J.; Stunz, Laura L.; Liu, Yan; Bishop, Gail A.

    2011-01-01

    We recently reported that TRAF3, a ubiquitously expressed adaptor protein, promotes mature B cell apoptosis. However, the specific function of TRAF3 in T cells has remained unclear. Here we report the generation and characterization of T cell-specific TRAF3−/− mice, in which the TRAF3 gene was deleted from thymocytes and T cells. Ablation of TRAF3 in the T cell-lineage did not affect the numbers or proportions of CD4+,CD8+ or double positive or negative thymocytes, or CD4 or CD8 T cell populations in secondary lymphoid organs except that the T cell specific TRAF3−/− mice had a two-fold increase in FoxP3+ T cells.. In striking contrast to mice lacking TRAF3 in B cells, the T cell TRAF3 deficient mice exhibited defective IgG1 responses to a T dependent antigen, and impaired T cell-mediated immunity to infection with Listeria monocytogenes. Surprisingly, we found that TRAF3 was recruited to the TCR/CD28 signaling complex upon co-stimulation, and that TCR/CD28-mediated proximal and distal signaling events were compromised by TRAF3 deficiency. These findings provide new insights into the roles played by TRAF3 in T cell activation and T cell-mediated immunity. PMID:21084666

  7. T cell-mediated modulation of mast cell function: heterotypic adhesion-induced stimulatory or inhibitory effects.

    PubMed

    Mekori, Yoseph A; Hershko, Alon Y

    2012-01-01

    Close physical proximity between mast cells and T cells has been demonstrated in several T cell mediated inflammatory processes such as rheumatoid arthritis and sarcoidosis. However, the way by which mast cells are activated in these T cell-mediated immune responses has not been fully elucidated. We have identified and characterized a novel mast cell activation pathway initiated by physical contact with activated T cells, and showed that this pathway is associated with degranulation and cytokine release. The signaling events associated with this pathway of mast cell activation have also been elucidated confirming the activation of the Ras mitogen-activated protein kinase systems. More recently, we hypothesized and demonstrated that mast cells may also be activated by microparticles released from activated T cells that are considered as miniature version of a cell. By extension, microparticles might affect the activity of mast cells, which are usually not in direct contact with T cells at the inflammatory site. Recent works have also focused on the effects of regulatory T cells (Treg) on mast cells. These reports highlighted the importance of the cytokines IL-2 and IL-9, produced by mast cells and T cells, respectively, in obtaining optimal immune suppression. Finally, physical contact, associated by OX40-OX40L engagement has been found to underlie the down-regulatory effects exerted by Treg on mast cell function. PMID:22566892

  8. T-Cell-Mediated Inflammatory Myopathies in HIV-Positive Individuals: A Histologic Study of 19 Cases.

    PubMed

    Hiniker, Annie; Daniels, Brianne H; Margeta, Marta

    2016-03-01

    T cell-mediated inflammatory myopathies (polymyositis [PM] and inclusion body myositis [IBM]) sometimes arise in conjunction with HIV infection; however, it is not understood whether PM and IBM arising in the context of HIV (HIV-PM and HV-IBM) differ from PM and IBM arising sporadically in HIV-negative individuals (sPM and sIBM). Here, we report the largest series of T cell-mediated inflammatory myopathies from HIV-infected patients (19 biopsies from 15 subjects); 5 cases were pathologically classified as PM (HIV-PM) and 14 as IBM (HIV-IBM). As with sporadic cases, quantitative immunohistochemistry for LC3, p62, and TDP-43 showed significantly greater percentage of stained fibers (% FS) in HIV-IBM compared to HIV-PM samples; however, there was no significant difference in % FS for any of the three markers between HIV-associated and sporadic cases. Despite histologic similarities between HIV-IBM and sIBM but in concordance with prior case reports, patients with HIV-IBM were significantly younger at diagnosis than patients with sIBM; in contrast, the mean age of HIV-PM and sPM patients was not significantly different. In summary, HIV-PM and HIV-IBM are morphologically similar to sPM and sIBM; thus, it remains unclear why patients with HIV-IBM, in contrast to patients with sIBM, sometimes show clinical improvement in response to immunosuppressive therapy. PMID:26843609

  9. Antiviral protection following immunization correlates with humoral but not cell-mediated immunity.

    PubMed

    Panchanathan, Vijay; Chaudhri, Geeta; Karupiah, Gunasegaran

    2010-01-01

    Smallpox was a deadly disease when it was rife yet despite its eradication more than 30 years ago, the possibility of accidental or intentional release has driven research in search of better definitions of correlates of protective immunity. Mousepox, a disease caused by ectromelia virus (ECTV), is arguably one of the best surrogate small animal models for smallpox. Correlates of protection in mousepox are well defined during primary infection, whereas those in a secondary infection, which have definite relevance to vaccination strategies, are less well understood. We previously established that neutralizing antibody (Ab), which is generated far more rapidly during a secondary infection compared with a primary infection, has a key role during a secondary virus challenge. In this study, we show that the route of immunization or the use of homologous or heterologous virus vaccines for immunization does not influence the ability of mice to control high-dose virulent ECTV challenge or to mount a substantial secondary neutralizing Ab response. In contrast, the recall cytotoxic T lymphocyte (CTL) responses generated under these regimes of immunization were varied and did not correlate with virus control. Furthermore, unlike the recall Ab response that was generated rapidly, the kinetics of the secondary antiviral CTL response was no different to a primary infection and peaked only at day 8 post-challenge. This finding further underscores the importance of Ab in conferring protection during secondary poxvirus infection. This information could potentially prove useful in the design of safer and more efficacious vaccines against poxviruses or other diseases using poxvirus vectors. PMID:20066003

  10. Genetic Adjuvantation of Recombinant MVA with CD40L Potentiates CD8 T Cell Mediated Immunity

    PubMed Central

    Lauterbach, Henning; Pätzold, Juliane; Kassub, Ronny; Bathke, Barbara; Brinkmann, Kay; Chaplin, Paul; Suter, Mark; Hochrein, Hubertus

    2013-01-01

    Modified vaccinia Ankara (MVA) is a safe and promising viral vaccine vector that is currently investigated in several clinical and pre-clinical trials. In contrast to inactivated or sub-unit vaccines, MVA is able to induce strong humoral as well as cellular immune responses. In order to further improve its CD8 T cell inducing capacity, we genetically adjuvanted MVA with the coding sequence of murine CD40L, a member of the tumor necrosis factor superfamily. Immunization of mice with this new vector led to strongly enhanced primary and memory CD8 T cell responses. Concordant with the enhanced CD8 T cell response, we could detect stronger activation of dendritic cells and higher systemic levels of innate cytokines (including IL-12p70) early after immunization. Interestingly, acquisition of memory characteristics (i.e., IL-7R expression) was accelerated after immunization with MVA-CD40L in comparison to non-adjuvanted MVA. Furthermore, the generated cytotoxic T-lymphocytes (CTLs) also showed improved functionality as demonstrated by intracellular cytokine staining and in vivo killing activity. Importantly, the superior CTL response after a single MVA-CD40L immunization was able to protect B cell deficient mice against a fatal infection with ectromelia virus. Taken together, we show that genetic adjuvantation of MVA can change strength, quality, and functionality of innate and adaptive immune responses. These data should facilitate a rational vaccine design with a focus on rapid induction of large numbers of CD8 T cells able to protect against specific diseases. PMID:23986761

  11. Dynamics of cytotoxic T cell subsets during immunotherapy predicts outcome in acute myeloid leukemia

    PubMed Central

    Sander, Frida Ewald; Rydström, Anna; Bernson, Elin; Kiffin, Roberta; Riise, Rebecca; Aurelius, Johan; Anderson, Harald; Brune, Mats; Foà, Robin; Hellstrand, Kristoffer; Thorén, Fredrik B.; Martner, Anna

    2016-01-01

    Preventing relapse after chemotherapy remains a challenge in acute myeloid leukemia (AML). Eighty-four non-transplanted AML patients in first complete remission received relapse-preventive immunotherapy with histamine dihydrochloride and low-dose interleukin-2 in an international phase IV trial (ClinicalTrials.gov; NCT01347996). Blood samples were drawn during cycles of immunotherapy and analyzed for CD8+ (cytotoxic) T cell phenotypes in blood. During the first cycle of therapy, a re-distribution of cytotoxic T cells was observed comprising a reduction of T effector memory cells and a concomitant increase of T effector cells. The dynamics of T cell subtypes during immunotherapy prognosticated relapse and survival, in particular among older patients and remained significantly predictive of clinical outcome after correction for potential confounders. Presence of CD8+ T cells with specificity for leukemia-associated antigens identified patients with low relapse risk. Our results point to novel aspects of T cell-mediated immunosurveillance in AML and provide conceivable biomarkers in relapse-preventive immunotherapy. PMID:26863635

  12. Efficacy of a modified live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine in pigs naturally exposed to a heterologous European (Italian cluster) field strain: Clinical protection and cell-mediated immunity.

    PubMed

    Martelli, Paolo; Gozio, Stefano; Ferrari, Luca; Rosina, Stefano; De Angelis, Elena; Quintavalla, Cecilia; Bottarelli, Ezio; Borghetti, Paolo

    2009-06-01

    specific IFN-gamma production at 21-34 days PE were concomitant and associated to changes in natural killer (NK) cells, gamma/delta T, and cytotoxic T lymphocytes in the blood. In our field study, evidences of EU attenuated vaccine-induced clinical protection against natural exposure to a genetically diverse (84% homology) PRRSV-1 isolate (Italian cluster) was demonstrated by the statistically significant reduction in clinical signs in terms of incidence, duration and severity and by a more efficient cell-mediated immune response in the vaccinated pigs as compared to the unvaccinated controls. PMID:19442420

  13. Cytotoxic activity of Origanum dictamnus.

    PubMed

    Chinou, Ioanna; Liolios, Christos; Moreau, Dimitri; Roussakis, Christos

    2007-07-01

    Several extracts of Origanum dictamnus, an endemic plant of Greece growing only in the island of Crete and the bioassay-directed isolated ursolic acid, were tested in vitro against the P388 (murine leukemia) and the human bronchial epidermoid cancer NSCLC-N6 (non small cell lung cancer) cell lines. Both the initial dichloromethane extract and the isolated from it ursolic acid exhibited cytotoxic activity. Ursolic acid was also tested in vivo, on murine ascite leukemia P388, where it exhibited at a dose of 50 mg/kg a marginal antileukemic activity. PMID:17507178

  14. The cell mediated and humoral immune response to vaccination with acellular and whole cell pertussis vaccine in adult humans.

    PubMed

    Petersen, J W; Ibsen, P H; Bentzon, M W; Capiau, C; Heron, I

    1991-10-01

    The cell mediated immune response (CMI) against pertussis antigens following vaccination with the traditional Danish whole cell pertussis vaccine (WC-P) and the Japanese acellular pertussis vaccine (A-PV) JNIH-3 was studied in four adult human volunteers. Vaccination with the A-PV induced an in vitro proliferative response of peripheral blood lymphocytes to pertussis toxin (PT) subunits S2-S4, S3-S4 and S5 and the filamentous hemagglutinin (FHA), and a better serological response to native PT, detoxified PT (dPT) and FHA than the WC-PV. The induced CMI and serological response were followed over a period of 17 weeks, and were not seen to decline during this period. Further, an in vitro proliferative response to Bordetella pertussis agglutinogen 2 and 3 were demonstrated using lymphocytes from recently and not-so-recently pertussis-vaccinated adults. PMID:1797049

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

    PubMed

    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. PMID:23880363

  16. The role of cytokines and chemokines in the T-cell-mediated autoimmune process in alopecia areata.

    PubMed

    Ito, Taisuke; Tokura, Yoshiki

    2014-11-01

    The aetiology of alopecia areata (AA) is still not fully understood. However, recent clinical and experimental studies have provided insights into the pathomechanisms of AA and revealed that it is an organ-specific and cell-mediated autoimmune disease. Some triggers, such as viral infections, trauma, hormones and emotional/physical stressors, may cause activation of autoreactive T cells that target hair follicle (HF) autoantigens. In these immunological responses, cytokines and chemokines are regarded as key players that mediate the autoimmune inflammation. This results in the collapse of HF immune privilege, which is central to the pathogenesis of AA. This essay will focus on how cytokines and chemokines contribute to the immunological aspects of AA. The management of AA often remains difficult in a number of cases. Our review suggests that novel therapies for AA may involve targeting cytokines and chemokines. PMID:25040075

  17. In vivo testing confirms a blunting of the human cell-mediated immune mechanism during space flight

    NASA Technical Reports Server (NTRS)

    Taylor, G. R.; Janney, R. P.

    1992-01-01

    The cell-mediated immune (CMI) mechanism was evaluated in 10 space shuttle astronauts by measuring their delayed-type hypersensitivity response to seven common recall antigens. The Multitest CMI test system was used to administer antigens of tetanus, diphtheria, Streptococcus, Proteus, old tuberculin, Candida, and Trichophyton to the forearm 46 h before nominal mission termination; readings were conducted 2 h after landing. The mean number of reactions was reduced from 4.5 preflight to 3.0 inflight, and the mean reaction score was reduced from 21.4 to 13.7 mm inflight. The data presented suggest that the CMI system is still being degraded by space flight conditions on day 4 and that between day 5 and day 10, the depression maximizes and the system begins to adjust to the new conditions. The relation of these in vivo findings to previously reported in vitro results is discussed.

  18. Serotype-Specific Cell-Mediated Immunity Associated With Clearance of Homotypic Group B Streptococcus Rectovaginal Colonization in Pregnant Women.

    PubMed

    Kwatra, Gaurav; Adrian, Peter V; Shiri, Tinevimbo; Izu, Alane; Cutland, Clare L; Buchmann, Eckhart J; Madhi, Shabir A

    2016-06-15

    We investigated the association between group B Streptococcus (GBS) serotype-specific capsular polysaccharide cellular immunity, measured with enzyme-linked immunospot (ELISPOT) interferon γ release assay at 20 weeks gestation in pregnant women, and its effect on rectovaginal serotype-specific GBS colonization up to 37 weeks gestation. Among women colonized by serotype III at enrollment, interferon γ ELISPOT positivity was more common in those in whom colonization was cleared (44.4%) than in those in whom colonization persisted (7.4%; P = .008), with a similar trend observed for serotype Ia. Presence of serotype-specific capsular polysaccharide cell-mediated immunity contributes to the clearance of GBS rectovaginal colonization. PMID:27029777

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

    PubMed

    Omokoko, Tana A; Luxemburger, Uli; Bardissi, Shaheer; Simon, Petra; Utsch, Magdalena; Breitkreuz, Andrea; Türeci, Özlem; Sahin, Ugur

    2016-01-01

    Immunotherapy is rapidly evolving as an effective treatment option for many cancers. With the emerging fields of cancer vaccines and adoptive cell transfer therapies, there is an increasing demand for high-throughput in vitro cytotoxicity assays that efficiently analyze immune effector functions. The gold standard (51)Cr-release assay is very accurate but has the major disadvantage of being radioactive. We reveal the development of a versatile and nonradioactive firefly luciferase in vitro transcribed (IVT) RNA-based assay. Demonstrating high efficiency, consistency, and excellent target cell viability, our optimized luciferase IVT RNA is used to transfect dividing and nondividing primary antigen presenting cells. Together with the long-lasting expression and minimal background, the direct measurement of intracellular luciferase activity of living cells allows for the monitoring of killing kinetics and displays paramount sensitivity. The ability to cotransfect the IVT RNA of the luciferase reporter and the antigen of interest into the antigen presenting cells and its simple read-out procedure render the assay high-throughput in nature. Results generated were comparable to the (51)Cr release and further confirmed the assay's ability to measure antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. The assay's combined simplicity, practicality, and efficiency tailor it for the analysis of antigen-specific cellular and humoral effector functions during the development of novel immunotherapies. PMID:27057556

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

    PubMed Central

    Omokoko, Tana A.; Luxemburger, Uli; Bardissi, Shaheer; Simon, Petra; Utsch, Magdalena; Breitkreuz, Andrea; Türeci, Özlem; Sahin, Ugur

    2016-01-01

    Immunotherapy is rapidly evolving as an effective treatment option for many cancers. With the emerging fields of cancer vaccines and adoptive cell transfer therapies, there is an increasing demand for high-throughput in vitro cytotoxicity assays that efficiently analyze immune effector functions. The gold standard 51Cr-release assay is very accurate but has the major disadvantage of being radioactive. We reveal the development of a versatile and nonradioactive firefly luciferase in vitro transcribed (IVT) RNA-based assay. Demonstrating high efficiency, consistency, and excellent target cell viability, our optimized luciferase IVT RNA is used to transfect dividing and nondividing primary antigen presenting cells. Together with the long-lasting expression and minimal background, the direct measurement of intracellular luciferase activity of living cells allows for the monitoring of killing kinetics and displays paramount sensitivity. The ability to cotransfect the IVT RNA of the luciferase reporter and the antigen of interest into the antigen presenting cells and its simple read-out procedure render the assay high-throughput in nature. Results generated were comparable to the 51Cr release and further confirmed the assay's ability to measure antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity. The assay's combined simplicity, practicality, and efficiency tailor it for the analysis of antigen-specific cellular and humoral effector functions during the development of novel immunotherapies. PMID:27057556

  1. Induction of potent NK cell-dependent anti-myeloma cytotoxic T cells in response to combined mapatumumab and bortezomib

    PubMed Central

    Neeson, Paul J; Hsu, Andy K; Chen, Yin R; Halse, Heloise M; Loh, Joanna; Cordy, Reece; Fielding, Kate; Davis, Joanne; Noske, Josh; Davenport, Alex J; Lindqvist-Gigg, Camilla A; Humphreys, Robin; Tai, Tsin; Prince, H Miles; Trapani, Joseph A; Smyth, Mark J; Ritchie, David S

    2015-01-01

    There is increasing evidence that some cancer therapies can promote tumor immunogenicity to boost the endogenous antitumor immune response. In this study, we used the novel combination of agonistic anti-TRAIL-R1 antibody (mapatumumab, Mapa) with low dose bortezomib (LDB) for this purpose. The combination induced profound myeloma cell apoptosis, greatly enhanced the uptake of myeloma cell apoptotic bodies by dendritic cell (DC) and induced anti-myeloma cytotoxicity by both CD8+ T cells and NK cells. Cytotoxic lymphocyte expansion was detected within 24 h of commencing therapy and was maximized when myeloma-pulsed DC were co-treated with low dose bortezomib and mapatumumab (LDB+Mapa) in the presence of NK cells. This study shows that Mapa has two distinct but connected modes of action against multiple myeloma (MM). First, when combined with LDB, Mapa produced powerful myeloma cell apoptosis; secondly, it promoted DC priming and an NK cell-mediated expansion of anti-myeloma cytotoxic lymphocyte (CTL). Overall, this study indicates that Mapa can be used to drive potent anti-MM immune responses. PMID:26405606

  2. Rat liver endothelial and Kupffer cell-mediated mutagenicity and polycyclic aromatic hydrocarbons and aflatoxin B sub 1

    SciTech Connect

    Steinberg, P.; Schlemper, B.; Molitor, E.; Platt, K.L.; Seidel, A.; Oesch, F. )

    1990-08-01

    The ability of isolated rat liver endothelial and Kupffer cells to activate benzo(a)pyrene (BP), trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene (DDBP), trans-1,2-dihydroxy-1,2-dihydrochrysene (DDCH), and aflatoxin B{sub 1} (AFB{sub 1}) to mutagenic metabolites was assessed by means of a cell-mediated bacterial mutagenicity assay and compared with the ability of parenchymal cells to activate these compounds. Endothelial and Kupffer cells from untreated rats were able to activate AFB{sub 1} and DDBP; DDBP was activated even in the absence of an NADPH-generating system. Pretreating the animals with Aroclor 1254 strongly enhanced the mutagenicity of the dihydrodiol, whereas the mutagenicity of AFB{sub 1} showed a slight increase. BP and DDCH were only activated by endothelial and Kupffer cells isolated from Aroclor 1254-pretreated rats. Parenchymal cells form untreated animals activated all four carcinogens tested; Aroclor 1254 enhanced the parenchymal cell-mediated mutagenicity of BP and DDCH but did not affect that of DDBP and clearly reduced that of AFB{sub 1}. The reduced mutagenicity of AFB{sub 1} correlates with the decrease in the amount of 2{alpha}-hydroxytestosterone formed when testosterone was incubated with parenchymal cell microsomes from Aroclor 1254-pretreated rats (compared with microsomes from untreated animals): the formation of 2{alpha}-hydroxytestosterone is specifically catalyzed by cytochrome P-450h, a hemoprotein thought to be involved in the activation of AFB{sub 1}. These results show that not only rat liver parenchymal cells, but also endothelial and Kupffer cells, activated several carcinogens to mutagenic metabolites.

  3. Interference with intraepithelial TNF-α signaling inhibits CD8(+) T-cell-mediated lung injury in influenza infection.

    PubMed

    Srikiatkhachorn, Anon; Chintapalli, Jyothi; Liu, Jun; Jamaluddin, Mohammad; Harrod, Kevin S; Whitsett, Jeffrey A; Enelow, Richard I; Ramana, Chilakamarti V

    2010-12-01

    CD8(+) T-cell-mediated pulmonary immunopathology in respiratory virus infection is mediated in large part by antigen-specific TNF-α expression by antiviral effector T cells, which results in epithelial chemokine expression and inflammatory infiltration of the lung. To further define the signaling events leading to lung epithelial chemokine production in response to CD8(+) T-cell antigen recognition, we expressed the adenoviral 14.7K protein, a putative inhibitor of TNF-α signaling, in the distal lung epithelium, and analyzed the functional consequences. Distal airway epithelial expression of 14.7K resulted in a significant reduction in lung injury resulting from severe influenza pneumonia. In vitro analysis demonstrated a significant reduction in the expression of an important mediator of injury, CCL2, in response to CD8(+) T-cell recognition, or to TNF-α. The inhibitory effect of 14.7K on CCL2 expression resulted from attenuation of NF-κB activity, which was independent of Iκ-Bα degradation or nuclear translocation of the p65 subunit. Furthermore, epithelial 14.7K expression inhibited serine phosphorylation of Akt, GSK-3β, and the p65 subunit of NF-κB, as well as recruitment of NF-κB for DNA binding in vivo. These results provide insight into the mechanism of 14.7K inhibition of NF-κB activity, as well as further elucidate the mechanisms involved in the induction of T-cell-mediated immunopathology in respiratory virus infection. PMID:21142450

  4. Interference with Intraepithelial TNF-α Signaling Inhibits CD8+ T-Cell-Mediated Lung Injury in Influenza Infection

    PubMed Central

    Srikiatkhachorn, Anon; Chintapalli, Jyothi; Liu, Jun; Jamaluddin, Mohammad; Harrod, Kevin S.; Whitsett, Jeffrey A.; Enelow, Richard I.

    2010-01-01

    Abstract CD8+ T-cell-mediated pulmonary immunopathology in respiratory virus infection is mediated in large part by antigen-specific TNF-α expression by antiviral effector T cells, which results in epithelial chemokine expression and inflammatory infiltration of the lung. To further define the signaling events leading to lung epithelial chemokine production in response to CD8+ T-cell antigen recognition, we expressed the adenoviral 14.7K protein, a putative inhibitor of TNF-α signaling, in the distal lung epithelium, and analyzed the functional consequences. Distal airway epithelial expression of 14.7K resulted in a significant reduction in lung injury resulting from severe influenza pneumonia. In vitro analysis demonstrated a significant reduction in the expression of an important mediator of injury, CCL2, in response to CD8+ T-cell recognition, or to TNF-α. The inhibitory effect of 14.7K on CCL2 expression resulted from attenuation of NF-κB activity, which was independent of Iκ-Bα degradation or nuclear translocation of the p65 subunit. Furthermore, epithelial 14.7K expression inhibited serine phosphorylation of Akt, GSK-3β, and the p65 subunit of NF-κB, as well as recruitment of NF-κB for DNA binding in vivo. These results provide insight into the mechanism of 14.7K inhibition of NF-κB activity, as well as further elucidate the mechanisms involved in the induction of T-cell-mediated immunopathology in respiratory virus infection. PMID:21142450

  5. The human antibody fragment DIATHIS1 specific for CEACAM1 enhances natural killer cell cytotoxicity against melanoma cell lines in vitro.

    PubMed

    Dupuis, Maria L; Fiori, Valentina; 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:26448580

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

    SciTech Connect

    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 /sup 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.

  7. Cutting edge: An antibody recognizing ancestral endogenous virus glycoproteins mediates antibody-dependent cellular cytotoxicity on HIV-1-infected cells.

    PubMed

    Michaud, Henri-Alexandre; SenGupta, Devi; de Mulder, Miguel; Deeks, Steven G; Martin, Jeffrey N; Kobie, James J; Sacha, Jonah B; Nixon, Douglas F

    2014-08-15

    The failure of antiviral vaccines is often associated with rapid viral escape from specific immune responses. In the past, conserved epitope or algorithmic epitope selections, such as mosaic vaccines, have been designed to diversify immunity and to circumvent potential viral escape. An alternative approach is to identify conserved stable non-HIV-1 self-epitopes present exclusively in HIV-1-infected cells. We showed previously that human endogenous retroviral (HERV) mRNA transcripts and protein are found in cells of HIV-1-infected patients and that HERV-K (HML-2)-specific T cells can eliminate HIV-1-infected cells in vitro. In this article, we demonstrate that a human anti-HERV-K (HML-2) transmembrane protein Ab binds specifically to HIV-1-infected cells and eliminates them through an Ab-dependent cellular cytotoxicity mechanism in vitro. Thus, Abs directed against epitopes other than HIV-1 proteins may have a role in eliminating HIV-1-infected cells and could be targeted in novel vaccine approaches or immunotherapeutic modalities. PMID:25024383

  8. Cytoplasmic Delivery of Liposomes into MCF-7 Breast Cancer Cells Mediated by Cell-Specific Phage Fusion Coat Protein

    PubMed Central

    Wang, Tao; Yang, Shenghong; Petrenko, Valery A; Torchilin, Vladimir P

    2010-01-01

    Earlier, we have shown that doxorubicin-loaded liposomes (Doxil) modified with a chimeric phage fusion coat protein specific towards MCF-7 breast cancer cells identified from a phage landscape library demonstrated a significantly enhanced association with target cells and an increased cytotoxicity. Based on some structural similarities between the N-terminus of the phage potein and known fusogenic peptides, we hypothesized that, in addition to the specific targeting, the phage protein may possess endosome-escaping potential and an increased cytotoxicity of drug-loaded phage protein-targeted liposomes may be explained by an advantageous combination of both, cell targeting and endosomal escape of drug-loaded nanocarrier. The use of the fluorescence resonance energy transfer (FRET) technique allowed us to clearly demonstrate the pH-dependent membrane fusion activity of the phage protein. Endosomal escape and cytosolic delivery of phage-liposomes was visualized with fluorescence microscopy. Endosome acidification inhibition by bafilomycin A 1 resulted in decreased cytotoxicity of the phage-Doxil, while the endosome disruption by chloroquine had a negligible effect on efficacy of phage-Doxil, confirming its endosomal escape. Our results demonstrated an endosome-escaping property of the phage protein and provided an insight on mechanism of the enhanced cytotoxicity of phage-Doxil. PMID:20438086

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  10. Caloric Restriction reduces inflammation and improves T cell-mediated immune response in obese mice but concomitant consumption of curcumin/piperine adds no further benefit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity is associated with low-grade inflammation and impaired immune response. Caloric restriction (CR) has been shown to inhibit inflammatory response and enhance cell-mediated immune function. Curcumin, the bioactive phenolic component of turmeric spice, is proposed to have anti-obesity and anti-...

  11. Cytotoxic Aporphines from Artabotrys crassifolius.

    PubMed

    Kwan, Tan Kok; Shipton, Fiona; Azman, Nadiah Syafiqah Nor; Hossan, Shahadat; Jin, Khoo Ten; Wiart, Christophe

    2016-03-01

    Artabotrys crassifolius Hook. f. & Thomson is a medicinal plant used in Malaysia. The cytotoxic effects of the hexane, chloroform and ethanol extracts of the leaves and bark were examined in vitro against MCF-7, MDA-468 and HCT-116 cells. The chloroform extract of the bark inhibited the growth of all cell lines with GI₅₀ values ranging from 4.2 µg/mL to 9.4 µg/mL. Silica gel column chromatography of this extract yielded artabotrine, liridine, atherospermidine and lysicamine. Artabotrine and lysicamine inhibited the growth of HCT-116 and MCF-7 cells with GI₅₀ values ranging from 3.3 µM to 3.9 µM. These alkaloids were not toxic to human embryonic kidney cells (HEK297) up to a concentration of 50 µg/mL. PMID:27169188

  12. Lenalidomide enhances antibody-dependent cellular cytotoxicity of solid tumor cells in vitro: influence of host immune and tumor markers.

    PubMed

    Wu, Lei; Parton, Anastasia; Lu, Ling; Adams, Mary; Schafer, Peter; Bartlett, J Blake

    2011-01-01

    We evaluated the effect of combining lenalidomide with therapeutic antibodies on antibody-dependant cell-mediated cytotoxicity (ADCC) of solid tumor cells, and the requirement for expression of natural killer (NK) cell-activating receptors and their solid tumor surface ligands. Twenty-three human tumor cell lines (colon, breast, lung, head and neck, ovary, and bone sarcoma) were analyzed. NK effector cells were isolated from healthy donors, pre-treated with and without lenalidomide, and incubated with antibody-coated tumor cells to determine ADCC. In blocking experiments, NK cells were pre-incubated with anti-DNAM-1 or anti-NKG2D antibodies, and target colorectal cells were pre-incubated with anti-CD155 (PVR), anti-MIC-A/B, or anti-ULBP 3 antibodies. Differences between groups were assessed using unpaired and paired Student's t test and one-way ANOVA. Lenalidomide enhanced NK cell-mediated ADCC of trastuzumab- and cetuximab-coated tumor cells. Activity against colorectal cancer cells was dependent on target antigen expression, but independent of KRAS status and FcγRIIIa genotype. The extent of ADCC and its enhancement by lenalidomide correlated with NK cell expression of NKG2D and DNAM-1, and tumor cell expression of PVR and MIC-A. Blocking of NKG2D and, to a lesser extent, DNAM-1 inhibited ADCC. Anti-MIC-A/B monoclonal antibody blocked natural cytotoxicity, but not ADCC. Lenalidomide enhances the ability of IgG1-isotype antibodies to mediate ADCC of solid tumor cells, the extent of which is largely dependent on NKG2D-NKG2D ligand interactions, but appears to be independent of MIC-A/B. This provides a rationale for exploratory clinical studies and an assessment of potential biomarkers predictive of clinical benefit. PMID:20848094

  13. Host Genetic Background Influences the Response to the Opportunistic Pseudomonas aeruginosa Infection Altering Cell-Mediated Immunity and Bacterial Replication

    PubMed Central

    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

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

    PubMed

    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

  15. Cytotoxic components of bardanae fructus (goboshi).

    PubMed

    Moritani, S; Nomura, M; Takeda, Y; Miyamoto, K

    1996-11-01

    Bardanae Furctus (Goboshi) extract showed potent in vitro cytotoxicity and in vivo antitumor activity against human hepatoma HepG2 cells and mouse sarcoma 180 cells, respectively. In this study, the cytotoxicities of four fractions and three major components (arctiin, arctigenin, and chlorogenic acid) isolated from Goboshi extract were examined. Arctiin and arctigenin, which were contained in the ethylacetate fraction and n-butanol fraction, respectively, showed strong cytotoxicity against HepG2 cells, but little toxicity against Chang liver cells. Chlorogenic acid isolated from the water fraction did not affect the viability of these cells. The cytotoxicity of arctigenin against Chang liver cells was markedly potentiated by treatment with glutathione (GSH) synthesis inhibitor, L-buthionine-(S,R)-sulfoximine (BSO). On the other hand, in HepG2 cells, the cytotoxicity of arctigenin was hardly changed by BSO. The cytotoxicity of arctigenin against HepG2 cells increased in an exposure-time dependent manner. These characteristics of arctigenin were similar to those of Goboshi extract, as previously observed. We therefore conclude that the principal cytotoxic components of Goboshi extract are arctiin and its aglycone arctigenin. PMID:8951177

  16. Cytotoxic effects of bangladeshi medicinal plant extracts.

    PubMed

    Uddin, Shaikh J; Grice, I Darren; Tiralongo, Evelin

    2011-01-01

    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 (IC(50) 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 (IC(50) > 2.5 mg mL(-1)) against mouse fibroblasts but selective cytotoxicity (IC(50) 0.2-2.3 mg mL(-1)) against different cancer cell lines. The methanolic extract of Blumea lacera showed the highest cytotoxicity (IC(50) 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. PMID:19706693

  17. Cytotoxic Effects of Bangladeshi Medicinal Plant Extracts

    PubMed Central

    Uddin, Shaikh J.; Grice, I. Darren; Tiralongo, Evelin

    2011-01-01

    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. PMID:19706693

  18. PD-L1 Expression on Retrovirus-Infected Cells Mediates Immune Escape from CD8+ T Cell Killing.

    PubMed

    Akhmetzyanova, Ilseyar; Drabczyk, Malgorzata; Neff, C Preston; Gibbert, Kathrin; Dietze, Kirsten K; Werner, Tanja; Liu, Jia; Chen, Lieping; Lang, Karl S; Palmer, Brent E; Dittmer, Ulf; Zelinskyy, Gennadiy

    2015-10-01

    Cytotoxic CD8+ T Lymphocytes (CTL) efficiently control acute virus infections but can become exhausted when a chronic infection develops. Signaling of the inhibitory receptor PD-1 is an important mechanism for the development of virus-specific CD8+ T cell dysfunction. However, it has recently been shown that during the initial phase of infection virus-specific CD8+ T cells express high levels of PD-1, but are fully competent in producing cytokines and killing virus-infected target cells. To better understand the role of the PD-1 signaling pathway in CD8+ T cell cytotoxicity during acute viral infections we analyzed the expression of the ligand on retrovirus-infected cells targeted by CTLs. We observed increased levels of PD-L1 expression after infection of cells with the murine Friend retrovirus (FV) or with HIV. In FV infected mice, virus-specific CTLs efficiently eliminated infected target cells that expressed low levels of PD-L1 or that were deficient for PD-L1 but the population of PD-L1high cells escaped elimination and formed a reservoir for chronic FV replication. Infected cells with high PD-L1 expression mediated a negative feedback on CD8+ T cells and inhibited their expansion and cytotoxic functions. These findings provide evidence for a novel immune escape mechanism during acute retroviral infection based on PD-L1 expression levels on virus infected target cells. PMID:26484769

  19. PD-L1 Expression on Retrovirus-Infected Cells Mediates Immune Escape from CD8+ T Cell Killing

    PubMed Central

    Neff, C. Preston; Gibbert, Kathrin; Dietze, Kirsten K.; Werner, Tanja; Liu, Jia; Chen, Lieping; Lang, Karl S.; Palmer, Brent E.; Dittmer, Ulf; Zelinskyy, Gennadiy

    2015-01-01

    Cytotoxic CD8+ T Lymphocytes (CTL) efficiently control acute virus infections but can become exhausted when a chronic infection develops. Signaling of the inhibitory receptor PD-1 is an important mechanism for the development of virus-specific CD8+ T cell dysfunction. However, it has recently been shown that during the initial phase of infection virus-specific CD8+ T cells express high levels of PD-1, but are fully competent in producing cytokines and killing virus-infected target cells. To better understand the role of the PD-1 signaling pathway in CD8+ T cell cytotoxicity during acute viral infections we analyzed the expression of the ligand on retrovirus-infected cells targeted by CTLs. We observed increased levels of PD-L1 expression after infection of cells with the murine Friend retrovirus (FV) or with HIV. In FV infected mice, virus-specific CTLs efficiently eliminated infected target cells that expressed low levels of PD-L1 or that were deficient for PD-L1 but the population of PD-L1high cells escaped elimination and formed a reservoir for chronic FV replication. Infected cells with high PD-L1 expression mediated a negative feedback on CD8+ T cells and inhibited their expansion and cytotoxic functions. These findings provide evidence for a novel immune escape mechanism during acute retroviral infection based on PD-L1 expression levels on virus infected target cells. PMID:26484769

  20. Altered NK Cell Development and Enhanced NK Cell-Mediated Resistance to MCMV in NKG2D-Deficient Mice

    PubMed Central

    Zafirova, Biljana; Mandarić, Sanja; Antulov, Ronald; Krmpotić, Astrid; Jonsson, Helena; Yokoyama, Wayne M.; Jonjić, Stipan; Polić, Bojan

    2009-01-01

    Summary NKG2D is a potent activating receptor on NK cells which acts as a molecular sensor for stressed cells expressing NKG2D ligands such as infected or tumor transformed cells. Although NKG2D is expressed on NK cell precursors, its role in NK cell development is still not known. We have generated NKG2D-deficient mice by targeting the Klrk1 locus. Here we provide evidence for an important regulatory role of NKG2D in the development of NK cells. The absence of NKG2D causes faster division of NK cells, perturbation in size of some NK cell subpopulations and their augmented sensitivity to apoptosis. As expected, NKG2D−/− NK cells are less responsive to tumor targets expressing NKG2D ligands. NKG2D−/− mice, however, show an enhanced NK cell-mediated resistance to MCMV infection as a consequence of NK cell dysregulation. Altogether, these findings provide evidence for yet unknown regulatory function of NKG2D in NK cell physiology. PMID:19631564

  1. Intradermal delivery of DNA encoding HCV NS3 and perforin elicits robust cell-mediated immunity in mice and pigs.

    PubMed

    Grubor-Bauk, B; Yu, W; Wijesundara, D; Gummow, J; Garrod, T; Brennan, A J; Voskoboinik, I; Gowans, E J

    2016-01-01

    Currently, no vaccine is available against hepatitis C virus (HCV), and although DNA vaccines have considerable potential, this has not been realised. Previously, the efficacy of DNA vaccines for human immunodeficiency virus (HIV) and HCV was shown to be enhanced by including the gene for a cytolytic protein, viz. perforin. In this study, we examined the mechanism of cell death by this bicistronic DNA vaccine, which encoded the HCV non-structural protein 3 (NS3) under the control of the CMV promoter and perforin is controlled by the SV40 promoter. Compared with a canonical DNA vaccine and a bicistronic DNA vaccine encoding NS3 and the proapoptotic gene NSP4, the perforin-containing vaccine elicited enhanced cell-mediated immune responses against the NS3 protein in vaccinated mice and pigs, as determined by ELISpot and intracellular cytokine staining, whereas a mouse challenge model suggested that the immunity was CD8(+) T-cell-dependent. The results of the study showed that the inclusion of perforin in the DNA vaccine altered the fate of NS3-positive cells from apoptosis to necrosis, and this resulted in more robust immune responses in mice and pigs, the latter of which represents an accepted large animal model in which to test vaccine efficacy. PMID:26262584

  2. Cell-mediated Immunity to Human Tamm-Horsfall Glycoprotein in Autoimmune Liver Disease with Renal Tubular Acidosis

    PubMed Central

    Tsantoulas, D. C.; McFarlane, I. G.; Portmann, B.; Eddleston, A. L. W. F.; Williams, Roger

    1974-01-01

    Cell-mediated immune responses to Tamm-Horsfall glycoprotein isolated from human urine were investigated using the leucocyte migration test. Abnormal responses were found in 91% of patients with active chronic hepatitis or primary biliary cirrhosis with an associated renal tubular acidosis (R.T.A.) but in only 19% of those without R.T.A. In nearly all of a group of patients without autoimmune liver disease and in a control group of normal subjects results were within normal limits. In addition, using an immunofluorescent technique with rabbit antibody to human Tamm-Horsfall glycoprotein, it was possible to show the presence in human liver cell membrane of material reacting immunologically as Tamm-Horsfall. These findings suggest that the development of an immune response to this glycoprotein, initiated by release of cross-reacting antigens from damaged hepatocytes, could be the mechanism underlying the occurrence of R.T.A. in some patients with autoimmune liver disease. ImagesFIG. 3 PMID:4611578

  3. Cell-mediated and humoral immune responses after vaccination of human volunteers with the live vaccine strain of Francisella tularensis.

    PubMed

    Waag, D M; McKee, K T; Sandstrom, G; Pratt, L L; Bolt, C R; England, M J; Nelson, G O; Williams, J C

    1995-03-01

    The specific humoral and cell-mediated immune responses of human volunteers vaccinated with the Francisella tularensis live vaccine strain (LVS) were evaluated. In the search for an optimal antigen to measure the immunogenicity of the vaccine in an enzyme-linked immunosorbent assay, we tested irradiation-killed LVS, an aqueous ether extract of the LVS (EEx), lipopolysaccharide (LPS) from LVS, and a virulent strain (SCHU4). Volunteers were immunized with LVS by scarification. Immunoglobulin G (IgG) responses to LVS and LPS gave the highest background titers when tested with sera from unimmunized volunteers, whereas IgA, IgG, and IgM background titers to EEx and SCHU4 were low. Vaccination caused a significant rise (P < 0.01) in IgA, IgG, and IgM titers to all antigens tested, except for the IgG response to LPS. Eighty percent of vaccinated volunteers developed a positive IgG response to EEx 14 days postvaccination, while 50% were positive to LVS. By day 14 after vaccination, 70% of immunized volunteers exhibited a positive response to EEx in an in vitro peripheral blood lymphocyte proliferation assay. EEx, a specific and sensitive antigen for evaluating immune responses of vaccinated volunteers, may be a superior antigen for the diagnosis of tularemia. PMID:7697521

  4. New approaches for predicting T cell-mediated drug reactions: A role for inducible and potentially preventable autoimmunity.

    PubMed

    Michels, Aaron W; Ostrov, David A

    2015-08-01

    Adverse drug reactions (ADRs) are commonplace and occur when a drug binds to its intended pharmacologic target (type A ADR) or an unintended target (type B ADR). Immunologically mediated type B ADRs, such as drug hypersensitivity syndrome, drug reaction with eosinophilia and systemic symptoms syndrome, and Stevens-Johnson syndrome/toxic epidermal necrolysis, can be severe and result in a diverse set of clinical manifestations that include fever and rash, as well as multiple organ failure (liver, kidney, lungs, and/or heart) in the case of drug hypersensitivity syndrome. There is increasing evidence that specific HLA alleles influence the risk of drug reactions. Several features of T cell-mediated ADRs are strikingly similar to those displayed by patients with autoimmune diseases like type I diabetes, such as strong HLA association, organ-specific adaptive immune responses, viral involvement, and activation of innate immunity. There is a need to better predict patient populations at risk for immunologically mediated type B ADRs. Because methods to predict type 1 diabetes by using genetic and immunologic biomarkers have been developed to a high level of accuracy (predicting 100% of subjects likely to progress), new research strategies based on these methods might also improve the ability to predict drug hypersensitivity. PMID:26254052

  5. Reversal of CD8 T-cell-mediated mucocutaneous graft-versus-host-like disease by the JAK inhibitor tofacitinib.

    PubMed

    Okiyama, Naoko; Furumoto, Yasuko; Villarroel, Vadim A; Linton, Jay T; Tsai, Wanxia L; Gutermuth, Jan; Ghoreschi, Kamran; Gadina, Massimo; O'Shea, John J; Katz, Stephen I

    2014-04-01

    The utility of allogeneic hematopoietic stem cell transplantation is limited by graft-versus-host disease (GVHD), a significant cause of morbidity and mortality. Patients with GVHD exhibit cutaneous manifestations with histological features of interface dermatitis followed by scleroderma-like changes. JAK inhibitors represent a class of immunomodulatory drugs that inhibit signaling by multiple cytokines. Herein we report the effects of tofacitinib in a murine model of GVHD. Oral administration of tofacitinib prevented GVHD-like disease manifested by weight loss and mucocutaneous lesions. More importantly, tofacitinib was also effective in reversing established disease. Tofacitinib diminished the expansion and activation of murine CD8 T cells in this model, and had similar effects on IL-2-stimulated human CD8 T cells. Tofacitinib also inhibited the expression of IFN-γ-inducible chemoattractants by keratinocytes, and IFN-γ-inducible cell death of keratinocytes. Tofacitinib may be an effective drug for treatment against CD8 T-cell-mediated mucocutaneous diseases in patients with GVHD. PMID:24213371

  6. Allogeneic cell-mediated immunotherapy for breast cancer after autologous stem cell transplantation: a clinical pilot study.

    PubMed

    Or, R; Ackerstein, A; Nagler, A; Kapelushnik, J; Naparstek, E; Samuel, S; Amar, A; Bruatbar, C; Slavin, S

    1998-03-01

    Allogeneic cell therapy (allo-CT) is emerging as an effective treatment for patients relapsing after allogeneic bone marrow transplantation (BMT), indicating that tumor cells resisting chemoradiotherapy may still respond to immunocompetent allogeneic lymphocytes. We investigated possible graft-versus-tumor (GVT) effects in six patients with metastatic breast cancer that would be comparable to the graft-versus-leukemia (GVL) phenomenon occurring after allogeneic BMT in hematologic malignancies. The patients were cytoreduced with high-dose chemotherapy and autologous stem cell transplantation (ASCT), and were treated ambulatory with allo-CT consisting of adoptive transfer of HLA-matched donor peripheral blood lymphocytes (PBL) activated in vivo with human recombinant interleukin-2 (rIL-2). If no graft-versus-host disease (GVHD) developed, allo-CT was augmented with infusion of donor PBL, preactivated in vitro with rIL-2. Treatment was well tolerated, with low therapy-related toxicity in all patients. Two patients developed signs and symptoms compatible with GVHD grade I-II, one of whom shows no evidence of disease at more than 34 months out. In the remaining patients, progression-free survival following allo-CT ranged between 7 and 13 months. Allogeneic cell-mediated, cytokine-activated immunotherapy might be utilized for induction of GVT in metastatic breast cancer. A search for techniques to boost chimerism without severe GVHD is indicated. PMID:9557210

  7. Colostral antibody-mediated and cell-mediated immunity contributes to innate and antigen-specific immunity in piglets.

    PubMed

    Bandrick, Meggan; Ariza-Nieto, Claudia; Baidoo, Samuel K; Molitor, Thomas W

    2014-03-01

    Immunoglobulins and immune cells are critical components of colostral immunity; however, their transfer to and function in the neonate, especially maternal lymphocytes, is unclear. Cell-mediated and antibody-mediated immunity in sow blood and colostrum and piglet blood before (PS) and after (AS) suckling were assessed to investigate transfer and function of maternal immunity in the piglet. CD4, CD8, and γδ lymphocytes were found in sow blood and colostrum and piglet blood PS and AS; each had a unique T lymphocyte profile. Immunoglobulins were detected in sow blood, colostrum, and in piglet blood AS; the immunoglobulin profile of piglet serum AS mimicked that of sow serum. These results suggest selectivity in lymphocyte concentration into colostrum and subsequent lymphocyte transfer into the neonate, but that immunoglobulin transfer is unimpeded. Assessment of colostral natural killer activity and antigen-specific proliferation revealed that colostral cells are capable of influencing the innate and specific immune response of neonatal pigs. PMID:24252519

  8. Empirical evidence of cold stress induced cell mediated and humoral immune response in common myna ( Sturnus tristis)

    NASA Astrophysics Data System (ADS)

    Sandhu, Mansur A.; Zaib, Anila; Anjum, Muhammad S.; Qayyum, Mazhar

    2015-11-01

    Common myna ( Sturnus tristis) is a bird indigenous to the Indian subcontinent that has invaded many parts of the world. At the onset of our investigation, we hypothesized that the immunological profile of myna makes it resistant to harsh/new environmental conditions. In order to test this hypothesis, a number of 40 mynas were caught and divided into two groups, i.e., 7 and 25 °C for 14 days. To determine the effect of cold stress, cell mediated and humoral immune responses were assessed. The macrophage engulfment percentage was significantly ( P < 0.05) higher at 25 °C rather than 7 °C either co-incubated with opsonized or unopsonized sheep red blood cells (SRBC). Macrophage engulfment/cell and nitric oxide production behaved in a similar manner. However, splenic cells plaque formation, heterophil to lymphocyte (H/L) ratio, and serum IgM or IgG production remained non-significant. There was a significant increase of IgG antibody production after a second immunization by SRBC. To the best of our knowledge, these findings have never been reported in the progression of this bird's invasion in frosty areas of the world. The results revealed a strengthened humoral immune response of myna and made this bird suitable for invasion in the areas of harsh conditions.

  9. Pig but not Human Interferon-γ Initiates Human Cell-Mediated Rejection of Pig Tissue in vivo

    NASA Astrophysics Data System (ADS)

    Sultan, Parvez; Murray, Allan G.; McNiff, Jennifer M.; Lorber, Marc I.; Askenase, Philip W.; Bothwell, Alfred L. M.; Pober, Jordan S.

    1997-08-01

    Split-thickness pig skin was transplanted on severe combined immunodeficient mice so that pig dermal microvessels spontaneously inosculated with mouse microvessels and functioned to perfuse the grafts. Pig endothelial cells in the healed grafts constitutively expressed class I and class II major histocompatibility complex molecules. Major histocompatibility complex molecule expression could be further increased by intradermal injection of pig interferon-γ (IFN-γ ) but not human IFN-γ or tumor necrosis factor. Grafts injected with pig IFN-γ also developed a sparse infiltrate of mouse neutrophils and eosinophils without evidence of injury. Introduction of human peripheral blood mononuclear cells into the animals by intraperitoneal inoculation resulted in sparse perivascular mononuclear cell infiltrates in the grafts confined to the pig dermis. Injection of pig skin grafts on mice that received human peripheral blood mononuclear cells with pig IFN-γ (but not human IFN-γ or heat-inactivated pig IFN-γ ) induced human CD4+ and CD8+ T cells and macrophages to more extensively infiltrate the pig skin grafts and injure pig dermal microvessels. These findings suggest that human T cell-mediated rejection of xenotransplanted pig organs may be prevented if cellular sources of pig interferon (e.g., passenger lymphocytes) are eliminated from the graft.

  10. Coupling of HIV-1 Antigen to the Selective Autophagy Receptor SQSTM1/p62 Promotes T-Cell-Mediated Immunity

    PubMed Central

    Andersen, Aram Nikolai; Landsverk, Ole Jørgen; Simonsen, Anne; Bogen, Bjarne; Corthay, Alexandre; Øynebråten, Inger

    2016-01-01

    Vaccines aiming to promote T-cell-mediated immune responses have so far showed limited efficacy, and there is a need for novel strategies. Studies indicate that autophagy plays an inherent role in antigen processing and presentation for CD4+ and CD8+ T cells. Here, we report a novel vaccine strategy based on fusion of antigen to the selective autophagy receptor sequestosome 1 (SQSTM1)/p62. We hypothesized that redirection of vaccine antigen from proteasomal degradation into the autophagy pathway would increase the generation of antigen-specific T cells. A hybrid vaccine construct was designed in which the antigen is fused to the C-terminus of p62, a signaling hub, and a receptor that naturally delivers ubiquitinated cargo for autophagic degradation. Fusion of the human immunodeficiency virus-1 antigen Gagp24 to p62 resulted in efficient antigen delivery into the autophagy pathway. Intradermal immunization of mice revealed that, in comparison to Gagp24 delivered alone, fusion to p62 enhanced the number of Gagp24-specific interferon-γ-producing T cells, including CD8+ T cells. The strategy may also have the potential to modulate the antigenic peptide repertoire. Because p62 and autophagy are highly conserved between species, we anticipate this strategy to be a candidate for the development of T-cell-based vaccines in humans. PMID:27242780

  11. Thy-1 Is Expressed in Hepatic Myofibroblasts and Not Oval Cells in Stem Cell-Mediated Liver Regeneration

    PubMed Central

    Dezső, Katalin; Jelnes, Peter; László, Viktória; Baghy, Kornélia; Bödör, Csaba; Paku, Sándor; Tygstrup, Niels; Bisgaard, Hanne Cathrine; Nagy, Peter

    2007-01-01

    Thy-1, a marker of hematopoietic stem cells, has been reported to be expressed by oval cells proliferating during stem cell-mediated regeneration in rat liver, suggesting a relationship between the two cell populations. Consequently, Thy-1 has become an accepted cell surface marker to sort hepatic oval cells. In the present study we used the well-characterized 2-acetylaminfluorene/partial hepatectomy model to induce transit-amplification of hepatic oval cells in the regenerating liver and characterized Thy-1 expression using Northern hybridization, quantitative reverse transcriptase-polymerase chain reaction analysis, immunofluorescence confocal microscopy, and immunoelectronmicroscopy. We found that Thy-1 expression was induced during transit-amplification of the oval cell population, but Thy-1 mRNA was not present in the α-fetoprotein-expressing oval cells. Thy-1 protein was consistently present outside the basement membrane surrounding the oval cells. It overlapped frequently with smooth muscle actin staining. A similar cellular localization of the Thy-1 protein was found on human liver specimens with ductular reactions obtained from patients with fulminant liver failure. Furthermore, Thy-1 was expressed by myofibroblasts in experimental liver fibrosis models without oval cell proliferation. We conclude that Thy-1 is not a marker of oval cells but is present on a subpopulation of myofibroblasts/stellate cells. PMID:17884967

  12. Tumoral NKG2D alters cell cycle of acute myeloid leukemic cells and reduces NK cell-mediated immune surveillance.

    PubMed

    Tang, Mingying; Acheampong, Desmond Omane; Wang, Youfu; Xie, Wei; Wang, Min; Zhang, Juan

    2016-06-01

    The stimulatory natural killer group 2 member D (NKG2D) lymphocyte receptor, initially discovered and expressed mostly on natural killer (NK) cells, T cells and natural killer T cells, can promote tumor immune surveillance. However, with increasing tumor grade, tumors themselves express NKG2D to self-stimulate oncogenic pathways. To confirm that cancer cells themselves express NKG2D, we have now investigated the role of the tumoral NKG2D in NK cell-mediated immune surveillance. Both anti-NKG2D and shRNA to that down-regulated tumoral NKG2D increased the number of cells in G1 phase and S phase, increased the expression of cyclin E-CDK2 and decreased P21. In addition, CD107a, IFN-γ and TNF-α increased when the cells were treated with anti-NKG2D which suggests that blocking tumoral NKG2D could augment tumor surveillance of NK cells. Altogether, tumoral NKG2D stimulates cell propagation and immune escape in acute myeloid leukemia cells. PMID:26740330

  13. Effect of early vitamin A supplementation on cell-mediated immunity in infants younger than 6 mo.

    PubMed

    Rahman, M M; Mahalanabis, D; Alvarez, J O; Wahed, M A; Islam, M A; Habte, D

    1997-01-01

    One hundred twenty infants were randomly assigned to receive either 15 mg vitamin A or placebo with each of three DPT/OPV (diphtheria, pertussis, tetanus/oral polio vaccine) immunizations at monthly intervals. Sixty-two received vitamin A and 58 received placebo. One month after the third supplementation dose, the response to the delayed cutaneous hypersensitivity test [multitest cell-mediated immunity (CMI) skin evaluation] for tetanus, diphtheria, and tuberculin (purified protein derivative, PPD) was the same in the vitamin A and placebo infants. The number of anergic infants was 17 (27%) and 19 (33%) in the vitamin A and placebo groups, respectively. The number of positive tests among well-nourished infants was significantly higher than that in malnourished infants irrespective of supplementation (P < 0.001). Among the infants with adequate serum retinol concentrations (> 0.7 mumol/L) after supplementation, the vitamin A-supplemented infants had a significantly higher proportion of positive CMI tests than the placebo infants (chi-square test: 8.99, P = 0.008). Among the infants with low serum retinol concentrations (< 0.7 mumol/L) after supplementation, vitamin A supplementation had no effect on CMI response. These results indicate that CMI in young infants was positively affected by vitamin A supplementation only in those infants whose vitamin A status was adequate (ie, serum retinol > 0.7 mumol/L) at the time of the CMI test. CMI was consistently better in well-nourished infants irrespective of supplementation. PMID:8988926

  14. Bacterial kidney disease as a model for studies of cell mediated immunity in rainbow trout (Oncorhynchus mykiss).

    PubMed

    Jansson, Eva; Hongslo, Thorbjörn; Johannisson, Anders; Pilström, Lars; Timmusk, Sirje; Norrgren, Leif

    2003-04-01

    A cell mediated immune (CMI) response was measured in vitro to heat-killed and to paraformaldehyde fixed Renibacterium salmoninarum (Rs) in rainbow trout (Oncorhynchus mykiss) experimentally challenged with live Rs. The mitogenic response to the T lymphocyte mitogen Concanavalin A (Con A) was reduced during samplings 4 to 6 weeks after immersion, but no effect of the response to the B lymphocyte mitogen lipopolysaccharide (LPS) was detected. The subpopulation of lymphocytes, detected by the monoclonal antibody 1C2, was decreased from the 4th week to the 5th week of infection, and remained at the decreased level up to 10 weeks post immersion. The proportion of Immunoglobulin (Ig) bearing lymphocytes was not affected during the Rs infection period. The humoral antibody level to heat-stable Rs-antigens was increased up to 10 weeks after immersion but after 27 weeks was reduced to a level similar to that of the non-challenged fish. An anamnestic response was demonstrated in challenged fish, as intraperitoneal injection of heat-treated Rs bacteria into Rs challenged fish elicited a stronger humoral antibody response compared with injection into non-challenged fish. PMID:12657537

  15. Sensitive colorimetric cytotoxicity measurement using alarmar blue.

    PubMed

    Page, B; Page, M

    1995-01-01

    Cytotoxicity testing of anticancer drugs requires techniques which are sensitive, reproductible and applicable to large scale testing using automated instruments. End point staining of cells or viability stains are reliable but they are often not sensitive enough or not suitable for automation. We have already described a fluorometric cytotoxicity assay using a non fluorescent substrate, Alarmar Blue, which upon reduction in living cells, yields a fluorescent product. This assay is sensitive and highly reproductible but it is limited since automated fluorescent plate readers are not found frequently in laboratories. The conditions are now described for using Alamar Blue as a substrate in a colorimetric cytotoxicity assay. This new economical assay could be used with advantage for large scale screening of cytotoxic agents in microtitration plates. PMID:21597689

  16. Cell Death Mechanisms Induced by Cytotoxic Lymphocytes

    PubMed Central

    Chávez-Galán, L; Arenas-Del Angel, M C; Zenteno, E; Chávez, R; Lascurain, R

    2009-01-01

    One of the functions of the immune system is to recognize and destroy abnormal or infected cells to maintain homeostasis. This is accomplished by cytotoxic lymphocytes. Cytotoxicity is a highly organized multifactor process. Here, we reviewed the apoptosis pathways induced by the two main cytotoxic lymphocyte subsets, natural killer (NK) cells and CD8+ T cells. In base to recent experimental evidence, we reviewed NK receptors involved in recognition of target-cell, as well as lytic molecules such as perforin, granzymes-A and -B, and granulysin. In addition, we reviewed the Fas-FasL intercellular linkage mediated pathway, and briefly the cross-linking of tumor necrosis factor (TNF) and TNF receptor pathway. We discussed three models of possible molecular interaction between lytic molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis. PMID:19254476

  17. Influence of Ganoderma lucidum (Curt.: Fr.) P. Karst. on T-cell-mediated immunity in normal and immunosuppressed mice line CBA/Ca.

    PubMed

    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. PMID:26459128

  18. The ability of Hepatitis B surface antigen DNA vaccine to elicit cell-mediated immune responses, but not antibody responses, was affected by the deglysosylation of S antigen.

    PubMed

    Xing, Yiping; Huang, Zuhu; Lin, Yan; Li, Jun; Chou, Te-Hui; Lu, Shan; Wang, Shixia

    2008-09-19

    Hepatitis B Virus (HBV) infection remains a major worldwide infectious disease with serious long-term morbidity and mortality. The limited selections of drug treatment are not able to control the progress of disease in people with active and persistent HBV infection. Immunotherapy to control the degree of viral infection is one possible alternative solution to this challenge. HBV DNA vaccines, with their strong ability to induce cell-mediated immune responses, offer an attractive option. HBV surface protein is important in viral immunity. Re-establishing anti-S immunity in chronic HBV infected patients will bring significant benefit to the patients. Previous studies have shown that HBV S DNA vaccines are immunogenic in a number of animal studies. In the current study, we further investigated the effect of glycosylation to the expression and immunogenicity of S DNA vaccines. Our results demonstrate that deglycosylation at the two potential N-linked glycosylation sites in S protein resulted in a significant decrease of S-specific cell-mediated immune responses, but did not affect anti-S antibody responses. This finding provides important direction to the development of S DNA vaccines to elicit the optimal and balanced antibody and cell-mediated immune responses to treat people with HBV chronic infections. PMID:18462847

  19. Protection in antibody- and T cell-mediated autoimmune diseases by antiinflammatory IgG Fcs requires type II FcRs.

    PubMed

    Fiebiger, Benjamin M; Maamary, Jad; Pincetic, Andrew; Ravetch, Jeffrey V

    2015-05-01

    The antiinflammatory activity of intravenous immunoglobulin (IVIG) is dependent on the presence of sialic acid in the core IgG fragment crystallizable domain (Fc) glycan, resulting in increased conformational flexibility of the CH2 domain with corresponding modulation of Fc receptor (FcR) binding specificity from type I to type II receptors. Sialylated IgG Fc (sFc) increases the activation threshold of innate effector cells to immune complexes by stimulating the up-regulation of the inhibitory receptor FcγRIIB. We have found that the structural alterations induced by sialylation can be mimicked by specific amino acid modifications to the CH2 domain. An IgG Fc variant with a point mutation at position 241 (F→A) exhibits antiinflammatory activity even in the absence of sialylation. F241A and sFc protect mice from arthritis in the K/BxN-induced model and, in the T cell-mediated experimental autoimmune encephalomyelitis (EAE) mouse model, suppress disease by specifically activating regulatory T cells (Treg cells). Protection by these antiinflammatory Fcs in both antibody- and T cell-mediated autoimmune diseases required type II FcRs and the induction of IL-33. These results further clarify the mechanism of action of IVIG in both antibody- and T cell-mediated inflammatory diseases and demonstrate that Fc variants that mimic the structural alterations induced by sialylation, such as F241A, can be promising therapeutic candidates for the treatment of various autoimmune disorders. PMID:25870292

  20. Protection in antibody- and T cell-mediated autoimmune diseases by antiinflammatory IgG Fcs requires type II FcRs

    PubMed Central

    Fiebiger, Benjamin M.; Maamary, Jad; Pincetic, Andrew; Ravetch, Jeffrey V.

    2015-01-01

    The antiinflammatory activity of intravenous immunoglobulin (IVIG) is dependent on the presence of sialic acid in the core IgG fragment crystallizable domain (Fc) glycan, resulting in increased conformational flexibility of the CH2 domain with corresponding modulation of Fc receptor (FcR) binding specificity from type I to type II receptors. Sialylated IgG Fc (sFc) increases the activation threshold of innate effector cells to immune complexes by stimulating the up-regulation of the inhibitory receptor FcγRIIB. We have found that the structural alterations induced by sialylation can be mimicked by specific amino acid modifications to the CH2 domain. An IgG Fc variant with a point mutation at position 241 (F→A) exhibits antiinflammatory activity even in the absence of sialylation. F241A and sFc protect mice from arthritis in the K/BxN-induced model and, in the T cell-mediated experimental autoimmune encephalomyelitis (EAE) mouse model, suppress disease by specifically activating regulatory T cells (Treg cells). Protection by these antiinflammatory Fcs in both antibody- and T cell-mediated autoimmune diseases required type II FcRs and the induction of IL-33. These results further clarify the mechanism of action of IVIG in both antibody- and T cell-mediated inflammatory diseases and demonstrate that Fc variants that mimic the structural alterations induced by sialylation, such as F241A, can be promising therapeutic candidates for the treatment of various autoimmune disorders. PMID:25870292

  1. Flow cytometric assessment of chicken T cell-mediated immune responses after Newcastle disease virus vaccination and challenge.

    PubMed

    Dalgaard, T S; Norup, L R; Pedersen, A R; Handberg, K J; Jørgensen, P H; Juul-Madsen, H R

    2010-06-17

    The objective of this study was to use flow cytometry to assess chicken T cell-mediated immune responses. In this study two inbred genetic chicken lines (L130 and L133) were subjected to two times vaccination against Newcastle disease (ND) and a subsequent challenge by ND virus (NDV) infection. Despite a delayed NDV-specific antibody response to vaccination, L133 appeared to be better protected than L130 in the subsequent infection challenge as determined by the presence of viral genomes. Peripheral blood was analyzed by flow cytometry and responses in vaccinated/challenged birds were studied by 5-color immunophenotyping as well as by measuring the proliferative capacity of NDV-specific T cells after recall stimulation. Immunophenotyping identified L133 as having a significantly lower CD4/CD8 ratio and a lower frequency of gammadelta T cells than L130 in the peripheral T cell compartment. Furthermore, peripheral lymphocytes from L133 exhibited a significantly higher expression of CD44 and CD45 throughout the experiment. Interestingly, also vaccine-induced differences were observed in L133 as immune chickens had a significantly higher CD45 expression on their lymphocytes than the naïve controls. Immune chickens from both lines had a significantly higher frequency of circulating gammadelta T cells than the naïve controls both after vaccination and challenge. Finally, the proliferative capacity of peripheral CD4+ and CD8+ cells specific for NDV was addressed 3 weeks after vaccination and 1 week after infection and found to be significantly higher in L133 than in L130 at both sampling times. In conclusion, we found the applied flow cytometric methods very useful for the study of chicken T cell biology. PMID:20434546

  2. Protective cell-mediated immunity by DNA vaccination against Papillomavirus L1 capsid protein in the Cottontail Rabbit Papillomavirus model.

    PubMed

    Hu, Jiafen; Cladel, Nancy M; Budgeon, Lynn R; Reed, Cynthia A; Pickel, Martin D; Christensen, Neil D

    2006-01-01

    Papillomavirus major capsid protein L1 has successfully stimulated protective immunity against virus infection by induction of neutralizing antibodies in animal models and in clinical trials. However, the potential impact of L1-induced protective cell-mediated immune (CMI) responses is difficult to measure in vivo because of the coincidence of anti-L1 antibody. In this study, we tested the hypothesis that L1 could activate CMI, using the Cottontail Rabbit Papillomavirus (CRPV)-rabbit model. A unique property of this model is that infections can be initiated with viral DNA, thus bypassing all contributions to protection via neutralizing anti-L1 antibody. DNA vaccines containing either CRPV L1, or subfragments of L1 (amino-terminal two-thirds of L1 [L1N] and the carboxylterminal two-thirds of L1 [L1C]), were delivered intracutaneously into rabbits, using a gene gun. After three booster immunizations, the rabbits were challenged with several viral DNA constructs: wild-type CRPV, CRPV L1ATGko (an L1 ATG knockout mutation), and CRPV-ROPV hybrid (CRPV with a replacement L1 from Rabbit Oral Papillomavirus). Challenge of L1 DNA-vaccinated rabbits with wild-type CRPV resulted in significantly fewer papillomas when compared with challenge with CRPV L1ATGko DNA. Significantly smaller papillomas were found in CRPV L1-, L1N-, and L1C-vaccinated rabbits. In addition, rabbits vaccinated with either L1 or L1N grew significantly fewer and smaller papillomas when challenged with CRPV-ROPV hybrid DNA. Therefore, CRPV L1 DNA vaccination induced CMI responses to CRPV DNA infections that can contribute to protective immunity. Cross-protective immunity against CRPV L1 and ROPV L1 was elicited in these CRPV L1- and subfragment-vaccinated rabbits. PMID:16987067

  3. Multivalent TB vaccines targeting the esx gene family generate potent and broad cell-mediated immune responses superior to BCG

    PubMed Central

    Villarreal, Daniel O; Walters, Jewell; Laddy, Dominick J; Yan, Jian; Weiner, David B

    2014-01-01

    Development of a broad-spectrum synthetic vaccine against TB would represent an important advance to the limited vaccine armamentarium against TB. It is believed that the esx family of TB antigens may represent important vaccine candidates. However, only 4 esx antigens have been studied as potential vaccine antigens. The challenge remains to develop a vaccine that simultaneously targets all 23 members of the esx family to induce enhanced broad-spectrum cell-mediated immunity. We sought to investigate if broader cellular immune responses could be induced using a multivalent DNA vaccine representing the esx family protein members delivered via electroporation. In this study, 15 designed esx antigens were created to cross target all members of the esx family. They were distributed into groups of 3 self-processing antigens each, resulting in 5 trivalent highly optimized DNA plasmids. Vaccination with all 5 constructs elicited robust antigen-specific IFN-γ responses to all encoded esx antigens and induced multifunctional CD4 Th1 and CD8 T cell responses. Importantly, we show that when all constructs are combined into a cocktail, the RSQ-15 vaccine, elicited substantial broad Ag-specific T cell responses to all esx antigens as compared with vaccination with BCG. Moreover, these vaccine-induced responses were highly cross-reactive with BCG encoded esx family members and were highly immune effective in a BCG DNA prime-boost format. Furthermore, we demonstrate the vaccine potential and immunopotent profile of several novel esx antigens never previously studied. These data highlight the likely importance of these novel immunogens for study as preventative or therapeutic synthetic TB vaccines in combination or as stand alone antigens. PMID:25424922

  4. Chronically Elevated Levels of Short-Chain Fatty Acids Induce T Cell-Mediated Ureteritis and Hydronephrosis.

    PubMed

    Park, Jeongho; Goergen, Craig J; HogenEsch, Harm; Kim, Chang H

    2016-03-01

    Short-chain fatty acids (SCFAs) are major products of gut microbial fermentation and profoundly affect host health and disease. SCFAs generate IL-10(+) regulatory T cells, which may promote immune tolerance. However, SCFAs can also induce Th1 and Th17 cells upon immunological challenges and, therefore, also have the potential to induce inflammatory responses. Because of the seemingly paradoxical SCFA activities in regulating T cells, we investigated, in depth, the impact of elevated SCFA levels on T cells and tissue inflammation in mice. Orally administered SCFAs induced effector (Th1 and Th17) and regulatory T cells in ureter and kidney tissues, and they induced T cell-mediated ureteritis, leading to kidney hydronephrosis (hereafter called acetate-induced renal disease, or C2RD). Kidney hydronephrosis in C2RD was caused by ureteral obstruction, which was, in turn, induced by SCFA-induced inflammation in the ureteropelvic junction and proximal ureter. Oral administration of all major SCFAs, such as acetate, propionate, and butyrate, induced the disease. We found that C2RD development is dependent on mammalian target of rapamycin activation, T cell-derived inflammatory cytokines such as IFN-γ and IL-17, and gut microbiota. Young or male animals were more susceptible than old or female animals, respectively. However, SCFA receptor (GPR41 or GPR43) deficiency did not affect C2RD development. Thus, SCFAs, when systemically administered at levels higher than physiological levels, cause dysregulated T cell responses and tissue inflammation in the renal system. The results provide insights into the immunological and pathological effects of chronically elevated SCFAs. PMID:26819206

  5. Immunotoxicity of aflatoxin B1: Impairment of the cell-mediated response to vaccine antigen and modulation of cytokine expression

    SciTech Connect

    Meissonnier, Guylaine M.; Pinton, Philippe; Laffitte, Joelle; Cossalter, Anne-Marie; Gong, Yun Yun; Wild, Christopher P.; Bertin, Gerard; Galtier, Pierre; Oswald, Isabelle P.

    2008-09-01

    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 {mu}g 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-{alpha}, IL-1{beta}, IL-6, IFN-{gamma}) 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-{gamma} 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.

  6. Trypanosoma cruzi Adjuvants Potentiate T Cell-Mediated Immunity Induced by a NY-ESO-1 Based Antitumor Vaccine

    PubMed Central

    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. Investigational treatment suspension and enhanced cell-mediated immunity at rebound followed by drug-free remission of simian AIDS

    PubMed Central

    2013-01-01

    Background HIV infection persists despite antiretroviral treatment (ART) and is reignited as soon as therapies are suspended. This vicious cycle is fueled by the persistence of viral reservoirs that are invulnerable to standard ART protocols, and thus therapeutic agents able to target these reservoirs are needed. One such agent, auranofin, has recently been shown to decrease the memory T-cell reservoir in chronically SIVmac251-infected macaques. Moreover, auranofin could synergize with a fully suppressive ART protocol and induce a drug-free post-therapy containment of viremia. Results We administered buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis currently in clinical trials for cancer, in combination with auranofin to chronically SIVmac251-infected macaques under highly-intensified ART (H-iART). The ART/auranofin/BSO therapeutic protocol was followed, after therapy suspension, by a significant decrease of viral RNA and DNA in peripheral blood as compared to pre-therapy levels. Drug-free post-therapy control of the infection was achieved in animals with pre-therapy viral loads ranging from values comparable to average human set points to levels largely higher. This control was dependent on the presence CD8+ cells and associated with enhanced levels of cell-mediated immune responses. Conclusions The level of post-therapy viral set point reduction achieved in this study is the largest reported so far in chronically SIVmac251-infected macaques and may represent a promising strategy to improve over the current “ART for life” plight. PMID:23866829

  8. Role of donor and host cells in muscle-derived stem cell-mediated bone repair: differentiation vs. paracrine effects

    PubMed Central

    Gao, Xueqin; Usas, Arvydas; Proto, Jonathan D.; Lu, Aiping; Cummins, James H.; Proctor, Alexander; Chen, Chien-Wen; Huard, Johnny

    2014-01-01

    Murine muscle-derived stem cells (MDSCs) have been shown capable of regenerating bone in a critical size calvarial defect model when transduced with BMP 2 or 4; however, the contribution of the donor cells and their interactions with the host cells during the bone healing process have not been fully elucidated. To address this question, C57/BL/6J mice were divided into MDSC/BMP4/GFP, MDSC/GFP, and scaffold groups. After transplanting MDSCs into the critical-size calvarial defects created in normal mice, we found that mice transplanted with BMP4GFP-transduced MDSCs healed the bone defect in 4 wk, while the control groups (MDSC-GFP and scaffold) demonstrated no bone healing. The newly formed trabecular bone displayed similar biomechanical properties as the native bone, and the donor cells directly participated in endochondral bone formation via their differentiation into chondrocytes, osteoblasts, and osteocytes via the BMP4-pSMAD5 and COX-2-PGE2 signaling pathways. In contrast to the scaffold group, the MDSC groups attracted more inflammatory cells initially and incurred faster inflammation resolution, enhanced angiogenesis, and suppressed initial immune responses in the host mice. MDSCs were shown to attract macrophages via the secretion of monocyte chemotactic protein 1 and promote endothelial cell proliferation by secreting multiple growth factors. Our findings indicated that BMP4GFP-transduced MDSCs not only regenerated bone by direct differentiation, but also positively influenced the host cells to coordinate and promote bone tissue repair through paracrine effects.—Gao, X., Usas, A., Proto, J. D., Lu, A., Cummins, J. H., Proctor, A., Chen, C.-W., Huard, J. Role of donor and host cells in muscle-derived stem cell-mediated bone repair: differentiation vs. paracrine effects. PMID:24843069

  9. Disappearance of T Cell-Mediated Rejection Despite Continued Antibody-Mediated Rejection in Late Kidney Transplant Recipients.

    PubMed

    Halloran, Philip F; Chang, Jessica; Famulski, Konrad; Hidalgo, Luis G; Salazar, Israel D R; Merino Lopez, Maribel; Matas, Arthur; Picton, Michael; de Freitas, Declan; Bromberg, Jonathan; Serón, Daniel; Sellarés, Joana; Einecke, Gunilla; Reeve, Jeff

    2015-07-01

    The prevalent renal transplant population presents an opportunity to observe the adaptive changes in the alloimmune response over time, but such studies have been limited by uncertainties in the conventional biopsy diagnosis of T cell-mediated rejection (TCMR) and antibody-mediated rejection (ABMR). To circumvent these limitations, we used microarrays and conventional methods to investigate rejection in 703 unselected biopsies taken 3 days to 35 years post-transplant from North American and European centers. Using conventional methods, we diagnosed rejection in 205 biopsy specimens (28%): 67 pure TCMR, 110 pure ABMR, and 28 mixed (89 designated borderline). Using microarrays, we diagnosed rejection in 228 biopsy specimens (32%): 76 pure TCMR, 124 pure ABMR, and 28 mixed (no borderline). Molecular assessment confirmed most conventional diagnoses (agreement was 90% for TCMR and 83% for ABMR) but revealed some errors, particularly in mixed rejection, and improved prediction of failure. ABMR was strongly associated with increased graft loss, but TCMR was not. ABMR became common in biopsy specimens obtained >1 year post-transplant and continued to appear in all subsequent intervals. TCMR was common early but progressively disappeared over time. In 108 biopsy specimens obtained 10.2-35 years post-transplant, TCMR defined by molecular and conventional features was never observed. We conclude that the main cause of kidney transplant failure is ABMR, which can present even decades after transplantation. In contrast, TCMR disappears by 10 years post-transplant, implying that a state of partial adaptive tolerance emerges over time in the kidney transplant population. PMID:25377077

  10. Lymphomas are sensitive to perforin-dependent cytotoxic pathways despite expression of PI-9 and overexpression of bcl-2.

    PubMed

    Godal, Robert; Keilholz, Ulrich; Uharek, Lutz; Letsch, Anne; Asemissen, Anne Marie; Busse, Antonia; Na, Il-Kang; Thiel, Eckhard; Scheibenbogen, Carmen

    2006-04-15

    There is considerable interest in immunotherapeutic approaches for lymphoma. The expression of proteinase inhibitor 9 (PI-9), a molecule that inactivates granzyme B, is considered an immune escape mechanism in lymphoma. Further, lymphomas frequently overexpress the antiapoptotic molecule bcl-2, which is able to inhibit perforin-dependent cytotoxic pathways. In this study, the impact of PI-9 and bcl-2 expression on the sensitivity of lymphomas to T- and natural killer (NK) cell-mediated cytotoxicity was analyzed. We found PI-9 expression in 10 of 18 lymphoma cell lines and in 9 of 14 primary lymphomas. Overexpression of bcl-2 was found in 8 of 18 cell lines and in 12 of 14 primary lymphomas. All lymphoma cells were sensitive to cytolysis by specific T cells and cytokine-activated NK cells, and no difference in sensitivity was observed with respect to PI-9 or bcl-2 expression. Cytolysis was mediated predominantly through perforin-dependent pathways despite expression of PI-9 and bcl-2. Interestingly, the majority of lymphoma cells were resistant to cytolysis by resting allogeneic NK cells. This was due to the failure of lymphomas to induce degranulation of resting NK cells. These results show that resistance to perforin-dependent pathways is not a relevant immune escape mechanism in lymphoma and therefore is unlikely to impair clinical outcome of immunotherapeutic approaches. PMID:16373664

  11. Anti-ovarian tumor response of donor peripheral blood mononuclear cells is due to infiltrating cytotoxic NK cells

    PubMed Central

    Pandey, Veethika; Oyer, Jeremiah L.; Igarashi, Robert Y.; Gitto, Sarah B.; Copik, Alicja J.; Altomare, Deborah A.

    2016-01-01

    Treatment of ovarian cancer, a leading cause of gynecological malignancy, has good initial efficacy with surgery and platinum/taxane-based chemotherapy, but poor long-term survival in patients. Inferior long-term prognosis is attributed to intraperitoneal spreading, relapse and ineffective alternate therapies. Adoptive cell therapy is promising for tumor remission, although logistical concerns impede widespread implementation. In this study, healthy PBMCs were used to examine the immune response in a mouse model with human ovarian cancer, where natural killer (NK) cells were found to be the effector cells that elicited an anti-tumor response. Presence of tumor was found to stimulate NK cell expansion in mice treated intraperitoneally with PBMC+Interleukin-2 (IL-2), as compared to no expansion in non-tumor-bearing mice given the same treatment. PBMC+IL-2 treated mice exhibiting NK cell expansion had complete tumor remission. To validate NK cell mediated anti-tumor response, the intratumoral presence of NK cells and their cytotoxicity was confirmed by immunohistochemistry and granzyme activity of NK cells recovered from the tumor. Collectively, this study highlights the significance of NK cell-cytotoxic response to tumor, which may be attributed to interacting immune cell types in the PBMC population, as opposed to clinically used isolated NK cells showing lack of anti-tumor efficacy in ovarian cancer patients. PMID:26802025

  12. The cytotoxicity study of praziquantel enantiomers

    PubMed Central

    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 <80 μM concentration could promote proliferation of macrophage cells (Raw264.7). Our research revealed that (R)-PZQ has lower 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. PMID:27445457

  13. The cytotoxicity study of praziquantel enantiomers.

    PubMed

    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 <80 μM concentration could promote proliferation of macrophage cells (Raw264.7). Our research revealed that (R)-PZQ has lower 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. PMID:27445457

  14. Fc-galactosylation modulates antibody-dependent cellular cytotoxicity of therapeutic antibodies.

    PubMed

    Thomann, Marco; Reckermann, Katharina; Reusch, Dietmar; Prasser, Jessica; Tejada, Max L

    2016-05-01

    The therapeutic activity of monoclonal antibodies can involve immune cell mediated effector functions including antibody-dependent cellular cytotoxicity (ADCC), an activity that is modulated by the structure of Fc-glycans, and in particular the lack of core fucose. The heterogeneity of these glycostructures and the inherent variability of traditional PBMC-based in vitro ADCC assays, have made it challenging to quantitatively assess the impact of other glycostructures on ADCC activity. We applied a quantitative NK cell based assay to generate a database consisting of Fc-glycostructure and ADCC data from 54 manufacturing batches of a CHO-derived monoclonal antibody. Explorative analysis of the data indicated that, apart from afucosylation, galactosylation levels could influence ADCC activity. We confirmed this hypothesis by demonstrating enhanced ADCC upon enzymatic hypergalactosylation of four different monoclonal antibodies derived using standard CHO manufacturing processes. Furthermore we quantitatively compare the effects of galactosylation and afucosylation in the context of glycan heterogeneity and demonstrate that while galactose can influence ADCC activity, afucosylation remains the primary driver of this activity. PMID:27058641

  15. NK cell education after allogeneic transplantation: dissociation between recovery of cytokine-producing and cytotoxic functions.

    PubMed

    Foley, Bree; Cooley, Sarah; Verneris, Michael R; Curtsinger, Julie; Luo, Xianghua; Waller, Edmund K; Weisdorf, Daniel J; Miller, Jeffrey S

    2011-09-01

    Natural killer (NK) cells mediate GVL effects after allogeneic hematopoietic cell transplantation (allo-HCT) by the production of inflammatory cytokines and by direct target lysis. The acquisition of both functions was presumed to be developmentally linked, but this linkage remained unstudied after allo-HCT. We tested the cytokine production and degranulation of reconstituting NK cells after adult unrelated donor or umbilical cord blood grafting. Recipients of T cell-depleted transplants, receiving no immune suppression, showed diminished NK cell degranulation. In contrast, degranulation was normal or increased after T-cell replete transplants given with immune suppression. Strikingly, target cell-induced IFNγ production was markedly diminished in all transplant settings, especially with T cell-depleted or naive T cell-containing umbilical cord blood grafts, suggesting a role for T cells in NK education. Although degranulation was similar in the KIR(+) and KIR(-) populations that coexpressed NKG2A, target cell-induced IFNγ production was limited to the subset of NK cells expressing KIR inhibited by self-ligands. Thus, cytokine production and cytotoxic function do not consistently coexist in NK cells reconstituting after allo-HCT. Exposure to IL-15 rapidly increased target-inducible IFNγ production, indicative of IL-15's potential as a therapeutic tool to enhance NK cell function to protect against infection and relapse after allo-HCT. PMID:21757615

  16. Safe handling of cytotoxics: guideline recommendations

    PubMed Central

    Easty, A.C.; Coakley, N.; Cheng, R.; Cividino, M.; Savage, P.; Tozer, R.; White, R.E.

    2015-01-01

    Background 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. Methods 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. Results 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. Conclusions 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. PMID:25684994

  17. Isoflavanones from Desmodium oxyphyllum and their cytotoxicity.

    PubMed

    Li, Yan-Ping; Li, Yin-Ke; Du, Gang; Yang, Hai-Yin; Gao, Xue-Mei; Hu, Qiu-Fen

    2014-01-01

    Two new isoflavanones, (3R)-7-hydroxy-4'-methoxy-5-methoxycarbonyl-isoflavanone (1) and (3R)-8-hydroxy-4'-methoxy-7-methoxycarbonyl-isoflavanone (2), together with seven known isoflavanones (3-9) were isolated from Desmodium oxyphyllum of the Leguminosae family. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compound 1 showed good cytotoxicity against NB4 and SHSY5Y cell lines with IC50 values of 3.1 and 2.5 μM; compound 2 exhibited cytotoxicity against PC3 cell lines with a IC50 value of 3.6 μM; compound 4 showed cytotoxicity against A549 and SHSY5Y cell lines with IC50 values of 3.6 and 2.8 μM; and compound 5 displayed cytotoxicity against NB4, SHSY5Y, and MCF7 cell lines with IC50 values of 2.6, 3.8, and 2.8 μM, respectively. Other compounds also showed moderate cytotoxicity for some tested cell lines with IC50 values between 5.4 and 8.8 μM. PMID:24749537

  18. Cytotoxicity and intracellular dissolution of nickel nanowires.

    PubMed

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

    2016-09-01

    The assessment of cytotoxicity of nanostructures is a fundamental step for their development as biomedical tools. As widely used nanostructures, nickel nanowires (Ni NWs) seem promising candidates for such applications. In this work, Ni NWs were synthesized and then characterized using vibrating sample magnetometry, energy dispersive X-Ray analysis, and electron microscopy. After exposure to the NWs, cytotoxicity was evaluated in terms of cell viability, cell membrane damage, and induced apoptosis/necrosis on the model human cell line HCT 116. The influence of NW to cell ratio (10:1 to 1000:1) and exposure times up to 72 hours was analyzed for Ni NWs of 5.4 μm in length, as well as for Ni ions. The results show that cytotoxicity markedly increases past 24 hours of incubation. Cellular uptake of NWs takes place through the phagocytosis pathway, with a fraction of the dose of NWs dissolved inside the cells. Cell death results from a combination of apoptosis and necrosis, where the latter is the outcome of the secondary necrosis pathway. The cytotoxicity of Ni ions and Ni NWs dissolution studies suggest a synergistic toxicity between NW aspect ratio and dissolved Ni, with the cytotoxic effects markedly increasing after 24 hours of incubation. PMID:26692167

  19. [Synthesis and cytotoxicity of allobetulin derivatives].

    PubMed

    Kazakova, O B; Smirnova, I E; Khusnutdinova, E F; Zhukova, O S; Fetisova, L V; Apryshko, G N; Medvedeva, N I; Iamansarov, E Iu; Baĭkova, I P; Nguen, Thanh Tra; Thu, Do Thi H

    2014-01-01

    The synthesis and screening of antitumor activity in vitro (cytotoxicity) of various oxygen, nitrogen, sulfur and platinum-containing derivatives of allobetulin, including different arrangements of the double bonds in the A and B rings, penta- and hexacyclic ring A, 21-acetyl-20,28-epoxy-18α,19βH-ursane-isomeric cycle E, was carry out. (3R,5R)-19β,28-Epoxy-4,5-seco-18α-olean-3(5)-ozonide and 2,3-indolo-21β-acetyl-20β,28-epoxy-18α, H-19β-ursane showed significant cytotoxic activity against melanoma MeWo and Leukemia SR cells, appropriately. (3S,5S)-Diastereomer of the first compound showed no cytotoxicity. PMID:25895356

  20. Spectrum and Possible Mechanism of Carrageenan Cytotoxicity

    PubMed Central

    Catanzaro, Phillip J.; Schwartz, Howard J.; Graham, Richard C.

    1971-01-01

    Carrageenan, a sulfated polygalactose which suppresses established delayed hypersensitivity in vivo, is shown to be cytotoxic to macrophages but not to lymphocytes in vitro. This cytotoxicity depends on the carrageenan concentration and degree of lysosomal differentiation but is independent of serum. Survival of macrophages in the presence of carrageenan can be enhanced temporarily by corticosteroids. Ultrastructural studies reveal that carrageenan is readily taken up by macrophages and stored in lysosomes, which subsequently swell and rupture, apparently resulting in cell death. The presence of corticosteroids temporarily retards lysosome swelling. It is suggested that carrageenan may exert its cytotoxic effect by causing osmotic rupture of lysosomes. The possible immunologic significance of these findings is discussed. ImagesFig 3Fig 4Fig 2Fig 5Fig 6Fig 1 PMID:5142272

  1. Cytotoxic triterpenoid saponins from Clematis tangutica.

    PubMed

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

    2016-10-01

    Eight previously undescribed oleanane-type triterpenoid saponins, clematangoticosides A-H, together with eight known saponins, were isolated from the whole plants of Clematis tangutica (Maxim.) Korsh. Their structures were elucidated by extensive spectroscopic analysis, in combination with chemical methods (acid hydrolysis and mild alkaline hydrolysis). Clematangoticosides D-G were found to be unusual 23, 28-bidesmosidic glycosides. The cytotoxic activities of all of the isolated saponins were evaluated against the four human cancer cell lines SGC-7901, HepG2, HL-60 and U251MG. Clematoside S, sapindoside B, kalopanax saponin A, and koelreuteria saponin A exhibited cytotoxicity against all of the test cancer cell lines with IC50 values in the range of 1.88-27.20 μM, while clematangoticoside D and F showed selective cytotoxicity against SGC-7901 with IC50 values of 24.22 and 21.35 μM, respectively. PMID:27262876

  2. Spontaneous and antibody-dependent cellular cytotoxicity by lymphocyte subpopulations in peripheral blood and spleen from adult untreated patients with Hodgkin's disease.

    PubMed Central

    Gupta, S; Fernandes, G

    1981-01-01

    Subpopulations of lymphocytes in the peripheral blood and spleen from adult untreated patients with Hodgkin's disease were studied for spontaneous (SCMC) and antibody-dependent cellular cytotoxicities (ADCC). Peripheral blood from seven of 24 patients demonstrated abnormally low T cell-mediated SCMC when compared to age- and sex-matched healthy controls. Only two of these patients also demonstrated low T cell ADCC and non-T cell-mediated SCMC and ADCC. T cell ADCC in the peripheral blood of patients with involved spleen was significantly higher (P less than 0.05) when compared to those in whom spleen was not involved. When SCMC and ADCC were compared between peripheral blood and splenic lymphocytes with regard to involvement of spleen by Hodgkin's disease, non-T cell SCMC in the involved spleen was significantly lower (P less than 0.05) than their peripheral blood non-T cell SCMC. SCMC and ADCC tended to be higher in patients with stages III and IV of Hodgkin's disease when compared to those with stages I and II. However, the differences were not statistically significant. No direct relationship was observed between T and SCMC or ADCC and the proportion of T cells with IgG Fc receptors (T gamma). The significance of these observations is discussed. PMID:6975681

  3. Cell-Mediated Immune Responses in Four-Year-Old Children after Primary Immunization with Acellular Pertussis Vaccines

    PubMed Central

    Ausiello, Clara M.; Lande, Roberto; Urbani, Francesca; la Sala, Andrea; Stefanelli, Paola; Salmaso, Stefania; Mastrantonio, Paola; Cassone, Antonio

    1999-01-01

    Cell-mediated immune (CMI) responses to Bordetella pertussis antigens (pertussis toxin [PT], pertactin [PRN], and filamentous hemagglutinin [FHA]) were assessed in 48-month-old recipients of acellular pertussis [aP] vaccines (either from Chiron-Biocine [aP-CB] or from SmithKline Beecham [aP-SB]) and compared to CMI responses to the same antigens at 7 months of age, i.e., 1 month after completion of the primary immunization cycle. None of the children enrolled in this study received any booster of pertussis vaccines or was affected by pertussis during the whole follow-up period. Overall, around 75% of 4-year-old children showed a CMI-positive response to at least one B. pertussis antigen, independently of the type of aP vaccine received, and the proportion of CMI responders were at least equal at 48 and 7 months of age. However, longitudinal examination of individual responses showed that from 20 (against PT) to 37% (against FHA) of CMI responders after primary immunization became negative at 48 months of age. This loss was more than compensated for by conversion to positive CMI responses, ranging from 36% against FHA to 69% against PRN, in other children who were CMI negative at 7 months of age. In 60 to 80% of these CMI converters, a lack of decline or even marked elevation of antibody (Ab) titers against B. pertussis antigens also occurred between 20 and 48 months of age. In particular, the frequency of seropositivity to PRN and FHA (but not to PT) was roughly three times higher in CMI converters than in nonconverters. The acquisition of CMI response to B. pertussis antigens in 48-month-old children was not associated with a greater frequency of coughing episodes lasting ≥7 days and was characterized by a prevalent type 1 cytokine profile, with high gamma interferon and low or no production of interleukin-5, reminiscent of cytokine patterns following immunization with whole-cell pertussis vaccine or natural infection. Our data imply that vaccination

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

    PubMed

    Pleidrup, Janne; Dalgaard, Tina S; Norup, Liselotte R; Permin, Anders; Schou, Torben W; Skovgaard, Kerstin; Vadekær, Dorte F; Jungersen, Gregers; Sørensen, Poul; Juul-Madsen, Helle R

    2014-01-01

    Potent vaccine efficiency is crucial for disease control in both human and livestock vaccination programmes. Free range chickens and chickens with access to outdoor areas have a high risk of infection with parasites including Ascaridia galli, a gastrointestinal nematode with a potential influence 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 responses after ND vaccination. Thus, significantly lower NDV serum titres were found in the A. galli-infected group as compared to the non-parasitized group early after vaccination. In addition, the A. galli-infected chickens showed significantly lower frequencies of NDV-specific T cells in peripheral blood three weeks after the first ND vaccination as compared to non-parasitized chickens. Finally, A. galli significantly increased local mRNA expression of IL-4 and IL-13 and significantly decreased TGF-ß4 expression in the jejunum two weeks after infection with A. galli. At the time of vaccination (six and nine weeks after A. galli infection) the local expression in the jejunum of both IFN-? and IL-10 was significantly decreased in A. galli-infected chickens. Upon challenge with the NDV LaSota strain, viral genomes persisted in the oral cavity for a slightly longer period of time in A. galli-infected 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

  5. Humoral and Cell-Mediated Immune Responses to Alternate Booster Schedules of Anthrax Vaccine Adsorbed in Humans.

    PubMed

    Quinn, Conrad P; Sabourin, Carol L; Schiffer, Jarad M; Niemuth, Nancy A; Semenova, Vera A; Li, Han; Rudge, Thomas L; Brys, April M; Mittler, Robert S; Ibegbu, Chris C; Wrammert, Jens; Ahmed, Rafi; Parker, Scott D; Babcock, Janiine; Keitel, Wendy; Poland, Gregory A; Keyserling, Harry L; El Sahly, Hana; Jacobson, Robert M; Marano, Nina; Plikaytis, Brian D; Wright, Jennifer G

    2016-04-01

    Protective antigen (PA)-specific antibody and cell-mediated immune (CMI) responses to annual and alternate booster schedules of anthrax vaccine adsorbed (AVA; BioThrax) were characterized in humans over 43 months. Study participants received 1 of 6 vaccination schedules: a 3-dose intramuscular (IM) priming series (0, 1, and 6 months) with a single booster at 42 months (4-IM); 3-dose IM priming with boosters at 18 and 42 months (5-IM); 3-dose IM priming with boosters at 12, 18, 30, and 42 months (7-IM); the 1970 licensed priming series of 6 doses (0, 0.5, 1, 6, 12, and 18 months) and two annual boosters (30 and 42 months) administered either subcutaneously (SQ) (8-SQ) or IM (8-IM); or saline placebo control at all eight time points. Antibody response profiles included serum anti-PA IgG levels, subclass distributions, avidity, and lethal toxin neutralization activity (TNA). CMI profiles included frequencies of gamma interferon (IFN-γ)- and interleukin 4 (IL-4)-secreting cells and memory B cells (MBCs), lymphocyte stimulation indices (SI), and induction of IFN-γ, IL-2, IL-4, IL-6, IL-1β, and tumor necrosis factor alpha (TNF-α) mRNA. All active schedules elicited high-avidity PA-specific IgG, TNA, MBCs, and T cell responses with a mixed Th1-Th2 profile and Th2 dominance. Anti-PA IgG and TNA were highly correlated (e.g., month 7,r(2)= 0.86,P< 0.0001, log10 transformed) and declined in the absence of boosters. Boosters administered IM generated the highest antibody responses. Increasing time intervals between boosters generated antibody responses that were faster than and superior to those obtained with the final month 42 vaccination. CMI responses to the 3-dose IM priming remained elevated up to 43 months. (This study has been registered at ClinicalTrials.gov under registration no. NCT00119067.). PMID:26865594

  6. Cytotoxic and antiplasmodial xanthones from Pentadesma butyracea.

    PubMed

    Zelefack, Fabien; Guilet, David; Fabre, Nicolas; Bayet, Christine; Chevalley, Séverine; Ngouela, Silvère; Lenta, Bruno Ndjakou; Valentin, Alexis; Tsamo, Etienne; Dijoux-Franca, Marie-Geneviève

    2009-05-22

    Four new xanthones, butyraxanthones A-D (1-4), were isolated from the stem bark of Pentadesma butyracea, together with six known xanthones (5-10) and a triterpenoid (lupeol). The structures of 1-4 were established by spectroscopic methods. Compounds 1-10 were tested in vitro for antiplasmodial activity against a Plasmodium falciparum chloroquine-resistant strain and for cytotoxicity against a human breast cancer cell line (MCF-7). Nearly all of these xanthones exhibited good antiplasmodial activity, and some of them also demonstrated potent cytotoxicity. PMID:19296616

  7. Cytotoxic Terpene Quinones from Marine Sponges

    PubMed Central

    Gordaliza, Marina

    2010-01-01

    The 1,4-benzoquinone moiety is a common structural feature in a large number of compounds that have received considerable attention owing to their broad spectrum of biological activities. The cytotoxic and antiproliferative properties of many natural sesquiterpene quinones and hydroquinones from sponges of the order Dictyoceratida, such as avarol, avarone, illimaquinone, nakijiquinone and bolinaquinone, offer promising opportunities for the development of new antitumor agents. The present review summarizes the structure and cytotoxicity of natural terpenequinones/hydroquinones and their bioactive analogues and derivatives. PMID:21339953

  8. Nucleotide chloramines and neutrophil-mediated cytotoxicity.

    PubMed

    Bernofsky, C

    1991-03-01

    Hypochlorite is a reactive oxidant formed as an end product of the respiratory burst in activated neutrophils. It is responsible for killing bacteria and has been implicated in neutrophil-mediated tissue injury associated with the inflammatory process. Although hypochlorite is a potent cytotoxic agent, the primary mechanism by which it exerts its effect is unclear. This review examines evidence that the primary event in hypochlorite cytotoxicity is the loss of adenine nucleotides from the target cell. This loss appears to be mediated by the formation of adenine nucleotide chloramines which are reactive intermediates with a free radical character and are capable of forming stable ligands with proteins and nucleic acids. PMID:1848195

  9. Cytotoxic polycyclic polyprenylated acylphloroglucinols from Hypericum attenuatum.

    PubMed

    Zhou, Zhong-bo; Zhang, Yang-mei; Pan, Ke; Luo, Jian-guang; Kong, Ling-yi

    2014-06-01

    Six new polycyclic polyprenylated acylphloroglucinols, attenuatumiones A-F (1-6), together with twelve known analogs (7-18) were isolated from the whole plant of Hypericum attenuatum. Their structures were elucidated by spectroscopic methods, and the absolute configuration of C-13 in attenuatumione C (3) was deduced via the circular dichroism datum of the in situ formed [Rh2(OCOCF3)4] complexes. All isolates were evaluated for the cytotoxic activities on three human cancer cell lines. Compound 3 showed moderate cytotoxic activities with IC50 values of 10.12 and 10.56 μM against SMMC7721 and U2OS, respectively. PMID:24603092

  10. Therapeutic blockade of LIGHT interaction with HVEM and LTβR attenuates in vivo cytotoxic allogeneic responses

    PubMed Central

    del Rio, Maria-Luisa; Fernandez-Renedo, Carlos; Scheu, Stefanie; Pfeffer, Klaus; Shintani, Yasushi; Kronenberg, Mitchell; Chaloin, Olivier; Schneider, Pascal; Rodriguez-Barbosa, Jose-Ignacio

    2016-01-01

    Background TNF/TNFR superfamily members conform a group of molecular interaction pathways of essential relevance during the process of T cell activation and differentiation towards effector cells and particularly for the maintenance phase of the immune response. Specific blockade of these interacting pathways, such as CD40/CD40L, contributes to modulate the deleterious outcome of allogeneic immune responses. We postulated that antagonizing the interaction of LIGHT expression on activated T cells with its receptors, HVEM and LTβR may decrease T cell-mediated allogeneic responses. Methods A flow cytometry competition assay was designed to identify anti-LIGHT monoclonal antibodies capable to prevent the interaction of mouse LIGHT with its receptors expressed on transfected cells. An antibody with the desired specificity was evaluated in a short-term in vivo allogeneic cytotoxic assay and tested for its ability to detect endogenous mouse LIGHT. Results We provide evidence for the first time that in mice, as previously described in humans, LIGHT protein is rapidly and transiently expressed after T cell activation, and this expression was stronger on CD8 T cells than on CD4 T cells. Two anti-LIGHT antibodies prevented interactions of mouse LIGHT with its two known receptors HVEM and LTβR. In vivo administration of anti-LIGHT antibody (clone 10F12) ameliorated host anti-donor short-term cytotoxic response in WT B6 mice, although to a lesser extent than that observed in LIGHT-deficient mice. Conclusions The therapeutic targeting of LIGHT may contribute to achieve a better control of cytotoxic responses refractory to current immunosuppressive drugs in transplantation. PMID:25226173

  11. Small-molecule inhibitors of NMO-IgG binding to aquaporin-4 reduce astrocyte cytotoxicity in neuromyelitis optica

    PubMed Central

    Tradtrantip, Lukmanee; Zhang, Hua; Anderson, Marc O.; Saadoun, Samira; Phuan, Puay-Wah; Papadopoulos, Marios C.; Bennett, Jeffrey L.; Verkman, A. S.

    2012-01-01

    Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of spinal cord and optic nerve caused by pathogenic autoantibodies (NMO-IgG) against astrocyte aquaporin-4 (AQP4). We developed a high-throughput screen to identify blockers of NMO-IgG binding to human AQP4 using a human recombinant monoclonal NMO-IgG and transfected Fisher rat thyroid cells stably expressing human M23-AQP4. Screening of ∼60,000 compounds yielded the antiviral arbidol, the flavonoid tamarixetin, and several plant-derived berbamine alkaloids, each of which blocked NMO-IgG binding to AQP4 without affecting AQP4 expression, array assembly, or water permeability. The compounds inhibited NMO-IgG binding to AQP4 in NMO patient sera and blocked NMO-IgG-dependent complement- and cell-mediated cytotoxicity with IC50 down to ∼5 μM. Docking computations identified putative sites of blocker binding at the extracellular surface of AQP4. The blockers did not affect complement-dependent cytotoxicity caused by anti-GD3 antibody binding to ganglioside GD3. The blockers reduced by >80% the severity of NMO lesions in an ex vivo spinal cord slice culture model of NMO and in mice in vivo. Our results provide proof of concept for a small-molecule blocker strategy to reduce NMO pathology. Small-molecule blockers may also be useful for other autoimmune diseases caused by binding of pathogenic autoantibodies to defined targets.—Tradtrantip, L., Zhang, H., Anderson, M. O., Saadoun, S., Phuan, P.-W., Papadopoulos, M. C., Bennett, J. L., Verkman, A. S. Small-molecule inhibitors of NMO-IgG binding to aquaporin-4 reduce astrocyte cytotoxicity in neuromyelitis optica. PMID:22319008

  12. The Human Antibody Fragment DIATHIS1 Specific for CEACAM1 Enhances Natural Killer Cell Cytotoxicity Against Melanoma Cell Lines In Vitro

    PubMed Central

    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

  13. New cytotoxic cucurbitacins from Wilbrandia ebracteata Cogn.

    PubMed

    Lang, Karen L; da Rosa Guimarães, Tatiana; Rocha Machado, Vanessa; Zimmermann, Lara A; Silva, Izabella T; Teixeira, Marina R; Durán, Fernando J; Palermo, Jorge A; Simões, Cláudia M O; Caro, Miguel S B; Schenkel, Eloir P

    2011-09-01

    Chemical investigation of the roots of Wilbrandia ebracteata Cogn. (Cucurbitaceae) led to the isolation of two new (1- 2) and four known (3- 6) cucurbitacins. Their structures were elucidated by NMR and MS and compared with related compounds. The in vitro cytotoxicity of isolated compounds was evaluated against RD, KB, HCT-8, and A549 cell lines showing strong activity. PMID:21472651

  14. Cytotoxic activity of four Mexican medicinal plants.

    PubMed

    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. PMID:22128430

  15. Cytotoxicity potentials of eleven Bangladeshi medicinal plants.

    PubMed

    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. PMID:25431796

  16. Ethanol cytotoxic effect on trophoblast cells.

    PubMed

    Clave, S; Joya, X; Salat-Batlle, J; Garcia-Algar, O; Vall, O

    2014-03-01

    Prenatal ethanol exposure may cause both, altered fetal neurodevelopment and impaired placental function. These disturbances can lead to growth retardation, which is one of the most prevalent features in Fetal Alcohol Syndrome (FAS). It is not known whether there is a specific pattern of cytotoxicity caused by ethanol that can be extrapolated to other cell types. The aim of this study was to determine the cytotoxic effects caused by sustained exposure of trophoblast cells to ethanol. The cytotoxic effect of sustained exposure to standard doses of ethanol on an in vitro human trophoblast cell line, JEG3, was examined. Viable cell count by exclusion method, total protein concentration, lactate dehydrogenase (LDH) activity and activation of apoptotic markers (P-H2AX, caspase-3 and PARP-1) were determined. Sustained exposure to ethanol decreased viable cell count and total protein concentration. LDH activity did not increased in exposed cells but apoptotic markers were detected. In addition, there was a dose-dependent relationship between ethanol concentration and apoptotic pathways activation. Sustained ethanol exposure causes cellular cytotoxicity by apoptotic pathways induction as a result of DNA damage. This apoptotic induction may partially explain the altered function of placental cells and the damage previously detected in other tissues. PMID:24374569

  17. Cytotoxicity Potentials of Eleven Bangladeshi Medicinal Plants

    PubMed Central

    Haque, Tania; 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. PMID:25431796

  18. Natural deep eutectic solvents: cytotoxic profile.

    PubMed

    Hayyan, Maan; Mbous, Yves Paul; Looi, Chung Yeng; Wong, Won Fen; Hayyan, Adeeb; Salleh, Zulhaziman; Mohd-Ali, Ozair

    2016-01-01

    The purpose of this study was to investigate the cytotoxic profiles of different ternary natural deep eutectic solvents (NADESs) containing water. For this purpose, five different NADESs were prepared using choline chloride as a salt, alongside five hydrogen bond donors (HBD) namely glucose, fructose, sucrose, glycerol, and malonic acid. Water was added as a tertiary component during the eutectics preparation, except for the malonic acid-based mixture. Coincidentally, the latter was found to be more toxic than any of the water-based NADESs. A trend was observed between the cellular requirements of cancer cells, the viscosity of the NADESs, and their cytotoxicity. This study also highlights the first time application of the conductor-like screening model for real solvent (COSMO-RS) software for the analysis of the cytotoxic mechanism of NADESs. COSMO-RS simulation of the interactions between NADESs and cellular membranes' phospholipids suggested that NADESs strongly interacted with cell surfaces and that their accumulation and aggregation possibly defined their cytotoxicity. This reinforced the idea that careful selection of NADESs components is necessary, as it becomes evident that organic acids as HBD highly contribute to the increasing toxicity of these neoteric mixtures. Nevertheless, NADESs in general seem to possess relatively less acute toxicity profiles than their DESs parents. This opens the door for future large scale utilization of these mixtures. PMID:27386357

  19. Cytotoxicity of the rhizome of medicinal plants

    PubMed Central

    Hossain, Shakhawoat; Kader, Golam; Nikkon, Farjana; Yeasmin, Tanzima

    2012-01-01

    Objective To investigate the cytotoxicity of the crude ethanol extract of the rhizome of Zingiber zerumbet (Z. zerumbet) (L) Smith. and Curcuma zedoaria (C. zedoaria) Rosc. against Artemia salina Leach. Methods Fresh rhizomes of Z. zerumbet (L) Smith. and C. zedoaria Rosc. were extracted separately in cold with ethanol (2.5 L) and after concentration a brownish syrupy suspension of ethanol extracts of Z. zerumbet (L) Smith. and C. zedoaria Rosc. was obtained. The cytotoxic effect of the crude ethanol extracts of both plants was determined by brine shrimp lethality bioassay. Results Crude ethanol extracts of the rhizome of Z. zerumbet (L) Smith. showed the highest cytotoxicity (LC50 was 1.24 µg/mL) against brine shrimp nauplii as compared with C. zedoaria Rosc. (LC50 was 33.593 µg/mL) after 24 h of exposure. Conclusions It can be concluded that the rhizome of Z. zerumbet (L) Smith. and C. zedoaria Rosc. can be used as a source of cytotoxic agent. PMID:23569881

  20. Exercise-induced stress inhibits both the induction and elicitation phases of in vivo T-cell-mediated immune responses in humans.

    PubMed

    Harper Smith, Adam D; Coakley, Sarah L; Ward, Mark D; Macfarlane, Andrew W; Friedmann, Peter S; Walsh, Neil P

    2011-08-01

    Little is known about the influence of exercise on induction and elicitation phases of in vivo immunity in humans. We used experimental contact-hypersensitivity, a clinically relevant in vivo measure of T cell-mediated immunity, to investigate the effects of exercise on induction and elicitation phases of immune responses to a novel antigen. The effects of 2 h-moderate-intensity-exercise upon the induction (Study One) and elicitation of in vivo immune memory (Study Two) to diphenylcyclopropenone (DPCP) were examined. Study One: matched, healthy males were randomly-assigned to exercise (N=16) or control (N=16) and received a primary DPCP exposure (sensitization), 20 min after either 2 h running at 60% V O(2peak) (EX) or 2 h seated rest (CON). Four weeks later, participants received a low, dose-series DPCP challenge (elicitation) on their upper inner arm, which was read at 24 and 48 h as clinical score, oedema (skinfold thickness) and redness (erythema). Study Two: pilot; 13 healthy males were sensitized to DPCP. Elicitation challenges were repeated every 4 weeks until responses reached a reproducible plateau. Then, N=9 from the pilot study completed both EX and CON trials in a randomized order. Elicitation challenges were applied and evaluated as in Study One. Results demonstrate that exercise-induced stress significantly impairs both the induction (oedema -53% at 48 h; P<0.001) and elicitation (oedema -19% at 48 h; P<0.05) phases of the in vivo T-cell-mediated immune response. These findings demonstrate that prolonged moderate-intensity exercise impairs the induction and elicitation phases of in vivo T-cell-mediated immunity. Moreover, the induction component of new immune responses appears more sensitive to systemic-stress-induced modulation than the elicitation component. PMID:21362469

  1. A novel liposome adjuvant DPC mediates Mycobacterium tuberculosis subunit vaccine well to induce cell-mediated immunity and high protective efficacy in mice.

    PubMed

    Liu, Xun; Da, Zejiao; Wang, Yue; Niu, Hongxia; Li, Ruiying; Yu, Hongjuan; He, Shanshan; Guo, Ming; Wang, Yong; Luo, Yanping; Ma, Xingming; Zhu, Bingdong

    2016-03-01

    Tuberculosis (TB) is a serious disease around the world, and protein based subunit vaccine is supposed to be a kind of promising novel vaccine against it. However, there is no effective adjuvant available in clinic to activate cell-mediated immune responses which is required for TB subunit vaccine. Therefore, it is imperative to develop new adjuvant. Here we reported an adjuvant composed of dimethyl dioctadecylammonium (DDA), Poly I:C and cholesterol (DPC for short). DDA can form a kind of cationic liposome with the ability to deliver and present antigen and can induce Th1 type cell-mediated immune response. Poly I:C, a ligand of TLR3 receptor, could attenuate the pathologic reaction induced by following Mycobacterium tuberculosis challenge. Cholesterol, which could enhance rigidity of lipid bilayer, is added to DDA and Poly I:C to improve the stability of the adjuvant. The particle size and Zeta-potential of DPC were analyzed in vitro. Furthermore, DPC was mixed with a TB fusion protein ESAT6-Ag85B-MPT64(190-198)-Mtb8.4-Rv2626c (LT70) to construct a subunit vaccine. The subunit vaccine-induced immune responses and protective efficacy against M. tuberculosis H37Rv infection in C57BL/6 mice were investigated. The results showed that the DPC adjuvant with particle size of 400nm and zeta potential of 40mV was in good stability. LT70 in the adjuvant of DPC generated strong antigen-specific humoral and cell-mediated immunity, and induced long-term higher protective efficacy against M. tuberculosis infection (5.41±0.38log10CFU) than traditional vaccine Bacillus Calmette-Guerin (BCG) (6.01±0.33log10CFU) and PBS control (6.53±0.26log10CFU) at 30 weeks post-vaccination. In conclusion, DPC would be a promising vaccine adjuvant with the ability to stimulate Th1 type cell-mediated immunity, and could be used in TB subunit vaccine. PMID:26845736

  2. Induction of synthesis of the cytolytic C9 (ninth component of complement)-related protein in human peripheral mononuclear cells by monoclonal antibody OKT3 or interleukin 2: correlation with cytotoxicity and lymphocyte phenotype

    SciTech Connect

    Martin, D.E.; Zalman, L.S.; Jung, G.; Mueller-Eberhard, H.J.

    1987-05-01

    Synthesis of the cytolytic C9-related protein (C9RP) was induced by activation of resting human peripheral T lymphocytes with the anti-CD3 antibody OKT3 or interleukin 2. Comparison of cellular cytotoxicity and C9RP content at various times during activation yielded a coefficient of correlation r = 0.92. During OKT3 stimulation of peripheral mononuclear cells, maximal C9RP content and cytotoxicity were observed by day 2 for 3, with subsequent decline to baseline values by day 5, whereas during interleukin 2 stimulation, both parameters reached the maximal level at days 3-5. After fluorescence-activated cell sorting, C9RP and cytotoxicity were quantitated in CD4/sup +/, CD8/sup +/, and Leu-19/sup +/ subsets. In OKT3-activated CD8/sup +/ cells, C9RP increased to approx. 3 x 10/sup 6/ molecules per cell, with a corresponding increase in lysis of human melanoma cells mediated by anti-CD3-anti-melanoma monoclonal antibody conjugates. Interleukin 2-stimulated CD8/sup +/ cell showed similar increases, but cytotoxicity was conjugate-independent. Activated CD4/sup +/ cells showed minimal increase in C9RP content. Leu-19/sup +/ cells, which exhibit natural killer cell activity, had a high C9RP content before stimulation.

  3. Wnt3a is critical for endothelial progenitor cell-mediated neural stem cell proliferation and differentiation.

    PubMed

    Du, Yibin; Zhang, Shuo; Yu, Tao; Du, Gongwen; Zhang, Hui; Yin, Zongsheng

    2016-09-01

    The present study aimed to determine whether co-culture with bone marrow‑derived endothelial progenitor cells (EPCs) affects the proliferation and differentiation of spinal cord-derived neural stem cells (NSCs), and to investigate the underlying mechanism. The proliferation and differentiation of the NSCs were evaluated by an MTT cell proliferation and cytotoxicity assay, and immunofluorescence, respectively. The number of neurospheres and the number of β‑tubulin III‑positive cells were detected by microscopy. The wingless‑type MMTV integration site family, member 3a (Wnt3a)/β-catenin signaling pathway was analyzed by western blot analysis and reverse transcription‑quantitative polymerase chain reaction to elucidate the possible mechanisms of EPC‑mediated NSC proliferation and differentiation. The results revealed that co‑culture with EPCs significantly induced NSC proliferation and differentiation. In addition, co‑culture with EPCs markedly induced the expression levels of Wnt3a and β‑catenin and inhibited the phosphorylation of glycogen synthase kinase 3β (GSK‑3β). By contrast, Wnt3a knockdown using a short hairpin RNA plasmid in the EPCs reduced EPC‑mediated NSC proliferation and differentiation, accompanied by inhibition of the EPC‑mediated expression of β‑catenin, and its phosphorylation and activation of GSK‑3β. Taken together, the findings of the present study demonstrated that Wnt3a was critical for EPC‑mediated NSC proliferation and differentiation. PMID:27484039

  4. TRAIL-expressing CD8+ T cells mediate tolerance following soluble peptide-induced peripheral T cell deletion

    PubMed Central

    Gurung, Prajwal; Kucaba, Tamara A.; Schoenberger, Stephen P.; Ferguson, Thomas A.; Griffith, Thomas S.

    2010-01-01

    Peripheral tolerance controls the action of self-reactive T cells that escape thymic deletion. We showed previously that deletion of Ag-specific CD4+ T cells induced a CD8+ Treg population that maintained tolerance by deleting T cells with the same Ag specificity. The present study explored the mechanism of action of these CD8+ Treg. Following OT-II T cell deletion by soluble OVA323–339, B6 mice were unresponsive to challenge after CFA/OVA immunization, and Trail−/− or Dr5−/− mice were immune, although all strains displayed similar OT-II peripheral deletion. Interestingly, B6 mice remained tolerant to OVA even after a second infusion of OT-II T cells. Tolerance could be transferred to naïve recipients using CD8+ T cells from B6 or Dr5−/− mice that experienced peptide-induced peripheral OT-II deletion but not from Trail−/− mice. Subsequent investigation found that the mechanism of action of the CD8+ Treg was TRAIL-mediated OT-II T cell deletion in a TCR-specific manner. Furthermore, the tolerance was transient, as it was established by 14 days after peptide injection but lost by Day 56. Together, these data provide evidence to suggest that the mechanism behind transient peripheral tolerance induced following T cell deletion is the cytotoxic activity of TRAIL-expressing CD8+ Treg. PMID:20807702

  5. Induction of foetal haemoglobin synthesis in erythroid progenitor stem cells: mediated by water-soluble components of Terminalia catappa.

    PubMed

    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. PMID:24470326

  6. Resveratrol oligomers isolated from Carex species inhibit growth of human colon tumorigenic cells mediated by cell cycle arrest.

    PubMed

    González-Sarrías, Antonio; Gromek, Samantha; Niesen, Daniel; Seeram, Navindra P; Henry, Geneive E

    2011-08-24

    Research has shown that members of the Carex genus produce biologically active stilbenoids including resveratrol oligomers. This is of great interest to the nutraceutical industry given that resveratrol, a constituent of grape and red wine, has attracted immense research attention due to its potential human health benefits. In the current study, five resveratrol oligomers (isolated from Carex folliculata and Carex gynandra ), along with resveratrol, were evaluated for antiproliferative effects against human colon cancer (HCT-116, HT-29, Caco-2) and normal human colon (CCD-18Co) cells. The resveratrol oligomers included one dimer, two trimers, and two tetramers: pallidol (1); α-viniferin (2) and trans-miyabenol C (3); and kobophenols A (4) and B (5), respectively. Although not cytotoxic, the resveratrol oligomers (1-5), as well as resveratrol, inhibited growth of the human colon cancer cells. Among the six stilbenoids, α-viniferin (2) was most active against the colon cancer cells with IC(50) values of 6-32 μM (>2-fold compared to normal colon cells). Moreover, α-viniferin (at 20 μM) did not induce apoptosis but arrested cell cycle (in the S-phase) for the colon cancer but not the normal colon cells. This study adds to the growing body of knowledge supporting the anticancer effects of resveratrol and its oligomers. Furthermore, Carex species should be investigated for their nutraceutical potential given that they produce biologically active stilbenoids such as α-viniferin. PMID:21761862

  7. Wnt3a is critical for endothelial progenitor cell-mediated neural stem cell proliferation and differentiation

    PubMed Central

    Du, Yibin; Zhang, Shuo; Yu, Tao; Du, Gongwen; Zhang, Hui; Yin, Zongsheng

    2016-01-01

    The present study aimed to determine whether co-culture with bone marrow-derived endothelial progenitor cells (EPCs) affects the proliferation and differentiation of spinal cord-derived neural stem cells (NSCs), and to investigate the underlying mechanism. The proliferation and differentiation of the NSCs were evaluated by an MTT cell proliferation and cytotoxicity assay, and immunofluorescence, respectively. The number of neurospheres and the number of β-tubulin III-positive cells were detected by microscopy. The wingless-type MMTV integration site family, member 3a (Wnt3a)/β-catenin signaling pathway was analyzed by western blot analysis and reverse transcription-quantitative polymerase chain reaction to elucidate the possible mechanisms of EPC-mediated NSC proliferation and differentiation. The results revealed that co-culture with EPCs significantly induced NSC proliferation and differentiation. In addition, co-culture with EPCs markedly induced the expression levels of Wnt3a and β-catenin and inhibited the phosphorylation of glycogen synthase kinase 3β (GSK-3β). By contrast, Wnt3a knockdown using a short hairpin RNA plasmid in the EPCs reduced EPC-mediated NSC proliferation and differentiation, accompanied by inhibition of the EPC-mediated expression of β-catenin, and its phosphorylation and activation of GSK-3β. Taken together, the findings of the present study demonstrated that Wnt3a was critical for EPC-mediated NSC proliferation and differentiation. PMID:27484039

  8. Gold Nanoparticles Inhibit Matrix Metalloproteases without Cytotoxicity.

    PubMed

    Hashimoto, M; Sasaki, J I; Yamaguchi, S; Kawai, K; Kawakami, H; Iwasaki, Y; Imazato, S

    2015-08-01

    Nanoparticles (NPs) are currently the focus of considerable attention for dental applications; however, their biological effects have not been fully elucidated. The long-term, slow release of matrix metalloproteases (MMPs) digests collagen fibrils within resin-dentin bonds. Therefore, MMP inhibitors can prolong the durability of resin-dentin bonds. However, there have been few reports evaluating the combined effect of MMP inhibition and the cytotoxic effects of NPs for dentin bonding. The aim of this study was to evaluate MMP inhibition and cytotoxic responses to gold (AuNPs) and platinum nanoparticles (PtNPs) stabilized by polyvinylpyrrolidone (PVP) in cultured murine macrophages (RAW264) by using MMP inhibition assays, measuring cell viability and inflammatory responses (quantitative reverse transcription polymerase chain reaction [RT-qPCR]), and conducting a micromorphological analysis by fluorescence and transmission electron microscopy. Cultured RAW264 cells were exposed to metal NPs at various concentrations (1, 10, 100, and 400 µg/mL). AuNPs and PtNPs markedly inhibited MMP-8 and MMP-9 activity. Although PtNPs were cytotoxic at high concentrations (100 and 400 µg/mL), no cytotoxic effects were observed for AuNPs at any concentration. Transmission electron microscopy images showed a significant nonrandom intercellular distribution for AuNPs and PtNPs, which were mostly observed to be localized in lysosomes but not in the nucleus. RT-qPCR analysis demonstrated inflammatory responses were not induced in RAW264 cells by AuNPs or PtNPs. The cytotoxicity of nanoparticles might depend on the core metal composition and arise from a "Trojan horse" effect; thus, MMP inhibition could be attributed to the surface charge of PVP, which forms the outer coating of NPs. The negative charge of the surface coating of PVP binds to Zn(2+) from the active center of MMPs by chelate binding and results in MMP inhibition. In summary, AuNPs are attractive NPs that effectively

  9. Long-term moderate calorie restriction inhibits inflammation without impairing cell-mediated immunity: a randomized controlled trial in non-obese humans

    PubMed Central

    Meydani, Simin N.; Das, Sai K.; Pieper, Carl F.; Lewis, Michael R.; Klein, Sam; Dixit, Vishwa D.; Gupta, Alok K.; Villareal, Dennis T.; Bhapkar, Manjushri; Huang, Megan; Fuss, Paul J.; Roberts, Susan B.; Holloszy, John O.; Fontana, Luigi

    2016-01-01

    Calorie restriction (CR) inhibits inflammation and slows aging in many animal species, but in rodents housed in pathogen-free facilities, CR impairs immunity against certain pathogens. However, little is known about the effects of long-term moderate CR on immune function in humans. In this multi-center, randomized clinical trial to determine CR's effect on inflammation and cell-mediated immunity, 218 healthy non-obese adults (20-50 y), were assigned 25% CR (n=143) or an ad-libitum (AL) diet (n=75), and outcomes tested at baseline, 12, and 24 months of CR. CR induced a 10.4% weight loss over the 2-y period. Relative to AL group, CR reduced circulating inflammatory markers, including total WBC and lymphocyte counts, ICAM-1 and leptin. Serum CRP and TNF-α concentrations were about 40% and 50% lower in CR group, respectively. CR had no effect on the delayed-type hypersensitivity skin response or antibody response to vaccines, nor did it cause difference in clinically significant infections. In conclusion, long-term moderate CR without malnutrition induces a significant and persistent inhibition of inflammation without impairing key in vivo indicators of cell-mediated immunity. Given the established role of these pro-inflammatory molecules in the pathogenesis of multiple chronic diseases, these CR-induced adaptations suggest a shift toward a healthy phenotype. PMID:27410480

  10. The ROS-induced cytotoxicity of ascorbate is attenuated by hypoxia and HIF-1alpha in the NCI60 cancer cell lines.

    PubMed

    Sinnberg, Tobias; Noor, Seema; Venturelli, Sascha; Berger, Alexander; Schuler, Paul; Garbe, Claus; Busch, Christian

    2014-03-01

    Intravenous application of high-dose ascorbate is used in complementary palliative medicine to treat cancer patients. Pharmacological doses of ascorbate in the mM range induce cytotoxicity in cancer cells mediated by reactive oxygen species (ROS), namely hydrogen peroxide and ascorbyl radicals. However, little is known about intrinsic or extrinsic factors modulating this ascorbate-mediated cytotoxicity. Under normoxia and hypoxia, ascorbate IC50 values were determined on the NCI60 cancer cells. The cell cycle, the influence of cobalt chloride-induced hypoxia-inducible factor-1α (HIF-1α) and the glucose transporter 1 (GLUT-1) expression (a pro-survival HIF-1α-downstream-target) were analysed after ascorbate exposure under normoxic and hypoxic conditions. The amount of ascorbyl radicals increased with rising serum concentrations. Hypoxia (0.1% O2 ) globally increased the IC50 of ascorbate in the 60 cancer cell lines from 4.5 ± 3.6 mM to 10.1 ± 5.9 mM (2.2-fold increase, P < 0.001, Mann-Whitney t-test), thus inducing cellular resistance towards ascorbate. This ascorbate resistance depended on HIF-1α-signalling, but did not correlate with cell line-specific expression of the ascorbate transporter GLUT-1. However, under normoxic and hypoxic conditions, ascorbate treatment at the individual IC50 reduced the expression of GLUT-1 in the cancer cells. Our data show a ROS-induced, HIF-1α- and O2 -dependent cytotoxicity of ascorbate on 60 different cancer cells. This suggests that for clinical application, cancer patients should additionally be oxygenized to increase the cytotoxic efficacy of ascorbate. PMID:24330097

  11. The ROS-induced cytotoxicity of ascorbate is attenuated by hypoxia and HIF-1alpha in the NCI60 cancer cell lines

    PubMed Central

    Sinnberg, Tobias; Noor, Seema; Venturelli, Sascha; Berger, Alexander; Schuler, Paul; Garbe, Claus; Busch, Christian

    2014-01-01

    Intravenous application of high-dose ascorbate is used in complementary palliative medicine to treat cancer patients. Pharmacological doses of ascorbate in the mM range induce cytotoxicity in cancer cells mediated by reactive oxygen species (ROS), namely hydrogen peroxide and ascorbyl radicals. However, little is known about intrinsic or extrinsic factors modulating this ascorbate-mediated cytotoxicity. Under normoxia and hypoxia, ascorbate IC50 values were determined on the NCI60 cancer cells. The cell cycle, the influence of cobalt chloride-induced hypoxia-inducible factor-1α (HIF-1α) and the glucose transporter 1 (GLUT-1) expression (a pro-survival HIF-1α-downstream-target) were analysed after ascorbate exposure under normoxic and hypoxic conditions. The amount of ascorbyl radicals increased with rising serum concentrations. Hypoxia (0.1% O2) globally increased the IC50 of ascorbate in the 60 cancer cell lines from 4.5 ± 3.6 mM to 10.1 ± 5.9 mM (2.2-fold increase, P < 0.001, Mann–Whitney t-test), thus inducing cellular resistance towards ascorbate. This ascorbate resistance depended on HIF-1α-signalling, but did not correlate with cell line-specific expression of the ascorbate transporter GLUT-1. However, under normoxic and hypoxic conditions, ascorbate treatment at the individual IC50 reduced the expression of GLUT-1 in the cancer cells. Our data show a ROS-induced, HIF-1α-and O2-dependent cytotoxicity of ascorbate on 60 different cancer cells. This suggests that for clinical application, cancer patients should additionally be oxygenized to increase the cytotoxic efficacy of ascorbate. PMID:24330097

  12. Cytotoxic activity of selected Nigerian plants.

    PubMed

    Sowemimo, A; van de Venter, M; Baatjies, L; Koekemoer, T

    2009-01-01

    Cancer is one of the most prominent human diseases which has stimulated scientific and commercial interest in the discovery of new anticancer agents from natural sources. The current study investigates the cytotoxic activity of ethanolic extracts of sixteen Nigerian plants used locally for the treatment of cancer using the MTT assay on the HeLa cell line. Sapium ellipticum leaves showed activity comparable to the reference compound Cisplatin and greater cytotoxic activity than Combretum paniculatum, Celosia trigyna, Drymaria cordata, Cyathula achyranthoides and Cyathula prostata. Justica extensa, Pupalia lappacea, Hedranthera barteri leaves, Alternanthera sessilis, Ethulia conyzoides leaves, Combretum zenkeri root, Sapium ellipticum stembark and Lannea nigritana stembark showed very low activity while Combretum molle, Adenanthera parvoniana and Lannea acida showed no activity. The results justify the use of Sapium, Combretum, Celosia, Drymaria and Cyathula in traditional treatment of cancer. PMID:20606772

  13. Cytotoxic diterpenoids from Rabdosia lophanthoides var. gerardianus.

    PubMed

    Lin, Chao-Zhan; Zhao, Wei; Feng, Xiu-Li; Liu, Fang-Le; Zhu, Chen-Chen

    2016-03-01

    Two new abietane diterpenoids, Gerardianin B (1) and Gerardianin C (2), one new lignan glycoside, Gerardianin D (3) and one new lupane-type triterpenoid, Gerardianol A (4), together with seven known abietane diterpenoids were isolated from the aerial parts of Rabdosia lophanthoides var. gerardianus. Their structures were determined by 1D and 2D NMR spectroscopic data. The cytotoxic activities of the nine diterpenoids were evaluated on human cancer cell lines. Compounds 6-11 exhibited significant cytotoxic activities against HepG2 cell lines with IC50 from 4.68 to 9.43μM and HCF-8 cell lines with IC50 from 9.12 to 13.53μM. PMID:26608401

  14. Cytotoxic steroidal saponins from Agave sisalana.

    PubMed

    Chen, Pi-Yu; Chen, Chin-Hui; Kuo, Ching-Chuan; Lee, Tzong-Huei; Kuo, Yueh-Hsiung; Lee, Ching-Kuo

    2011-06-01

    Two new steroidal saponins, 8 and 10, along with 7 known steroidal sapogenins and saponins (1-7) and a furostanol saponin (9) were isolated from Agave sisalana Perrine ex Engelm. The structures of these two new compounds were identified and characterized by 1D and 2D NMR spectroscopy and mass spectrometry. In addition, acid hydrolysis and GC-FID were used to confirm the sugar moieties of 8 and 10. The cytotoxic effects of 1-10 on MCF-7, NCI-H460, and SF-268 cancer cells were evaluated, and among them, compound 10 proved to be the most cytotoxic with IC₅₀ values of 1.2, 3.8, and 1.5 µM, respectively. PMID:21243587

  15. Cytotoxic activity of Vitex trifolia purpurea extracts.

    PubMed

    El-Sayed, Mortada M; El-Hashash, Maher M; Mohamed, Mona A; Korany, Tamer M

    2011-08-01

    Defatted 85% crude hot aqueous methanol extract of Vitex trifolia purpurea (AME) successively extracted with, chloroform and ethyl acetate. Cytotoxicity of (AME), chloroform methanol extract (CE), ethyl acetate methanol extract (EE) and the residue obtained from methanol extract after successive extraction (RME) have been evaluated on brine shrimp (Artemia salina) and Hep-G2 cell lines as well. In brine shrimp lethality bioassay the results revealed that the (RME) is the most potent one with LC50 value 173 microg/ml while LC50 values of (AME), (CE) and (EE) was 180, 199 and 286 microg/ml, respectively. As well as the results of cytotoxic assay against Hep-G2 cell lines are in full agreement with previous results, with IC50 values 6, 10.7, 20.8 and 65.8 microg/ml for (RME), (AME), (CE) and (EE), respectively. PMID:21980779

  16. Cytotoxic farnesyl glycosides from Pittosporum pancheri.

    PubMed

    Eparvier, Véronique; Thoison, Odile; Bousserouel, Hadjira; Guéritte, Françoise; Sévenet, Thierry; Litaudon, Marc

    2007-03-01

    Bioassay guided purification of the ethanolic extract of the bark of New Caledonian Pittosporum pancheri Brongn. and Gris (Pittosporaceae) led to the isolation and characterization of two new farnesyl monoglycosides, pancherins A and B. The structure of these compounds were determined on the basis of spectroscopic studies. The new compounds displayed a significant activity in the in vitro cytotoxic assay against KB cancer cell line, and pancherin A inhibits weakly farnesyl protein transferase. PMID:17174992

  17. Four new cytotoxic xanthones from Garcinia nujiangensis.

    PubMed

    Tang, Zhong-Yan; Xia, Zheng-Xiang; Qiao, Shi-Ping; Jiang, Chao; Shen, Guo-Rong; Cai, Mei-Xiang; Tang, Xiao-Yan

    2015-04-01

    Bioassay-guided fractionation of the acetone extract of the twigs of Garcinia nujiangensis resulted in the isolation of four new prenylated xanthones, nujiangexanthones C-F (1-4), and ten known related analogues. The structures of compounds 1-4 were elucidated by interpretation of their spectroscopic data. The compounds isolated were evaluated for their cytotoxic effects against three cancer cell lines, the test substances demonstrated selectivity toward the cancer cells. PMID:25727735

  18. Cytotoxicity screening of some South American Solanaceae.

    PubMed

    Moreno-Murillo, B; Fajardo, V M; Suárez, M

    2001-08-01

    Alcoholic extracts of seven plants belonging to the Solanaceae family were phytochemically screened and evaluated for their cytotoxic activity by Brine Shrimp Test (BST) with Artemia salina larvae, Inhibition of Cell Division Test (ICDT) on sea urchin Loxechinus albus fertilized eggs and inhibition of crown gall tumors on Potato Disk Bioassay (PDB). From Salpichroa diffusa, bioassay-guided chromatographic separation afforded some active fractions from which epi-katonic acid was identified. PMID:11543969

  19. Synthesis and cytotoxic activity of acetogenin analogues.

    PubMed

    Rodier, S; Le Huérou, Y; Renoux, B; Doyon, J; Renard, P; Pierré, A; Gesson, J P; Grée, R

    2000-06-19

    A set of 16 new simplified analogues of acetogenins has been designed based on: (i) the replacement of the bis THF moiety of these natural products by an ethylene glycol bis ether unit; (ii) the introduction of different lipophilic side chains (alkyl, aryl, dialkylamino, O-cholesteryl); (iii) the presence of the same terminal isolactone. In vitro cytotoxic activity against L1210 leukemia is reported. PMID:10890167

  20. Mycoplasma pneumoniae induces cytotoxic activity in guinea pig bronchoalveolar cells

    SciTech Connect

    Kist, M.; Koester, H.; Bredt, W.

    1985-06-01

    Precultured guinea pig alveolar macrophages (AM) and freshly harvested alveolar cells (FHAC) activated by interaction with Mycoplasma pneumoniae were cytotoxic for xenogeneic /sup 75/selenomethionine-labeled tumor target cells. Phagocytosis of whole opsonized or nonopsonized M. pneumoniae cells was more effective in eliciting cytotoxicity than uptake of sonicated microorganisms. The addition of living mycoplasma cells to the assay system enhanced the cytotoxic effect considerably. Target cells were significantly more susceptible to the cytotoxic action of phagocytes if they were coated with mycoplasma antigen or cocultured together with M. pneumoniae. The activation of the phagocytes could be inhibited by 2-deoxy-D-glucose but not by antimicrobial substances suppressing mycoplasma protein synthesis. It was accompanied by /sup 51/Cr release without detectable signs of cell damage. The supernatants of activated cells were cytotoxic for approximately 24 h. Inhibition, release, and cytotoxic activity indicate the necessity of an intact metabolism of the effector cells and suggest a secretion of cytotoxic substances.

  1. Neural Stem Cell-Mediated Delivery of Irinotecan-Activating Carboxylesterases to Glioma: Implications for Clinical Use

    PubMed Central

    Gutova, Margarita; Lacey, Simon F.; Abramyants, Yelena; Vo, Tien; Gilchrist, Megan; Tirughana, Revathiswari; Ghoda, Lucy Y.; Barish, Michael E.; Brown, Christine E.; Najbauer, Joseph; Potter, Philip M.; Portnow, Jana; Synold, Timothy W.

    2013-01-01

    CPT-11 (irinotecan) has been investigated as a treatment for malignant brain tumors. However, limitations of CPT-11 therapy include low levels of the drug entering brain tumor sites and systemic toxicities associated with higher doses. Neural stem cells (NSCs) offer a novel way to overcome these obstacles because of their inherent tumor tropism and ability to cross the blood-brain barrier, which enables them to selectively target brain tumor sites. Carboxylesterases (CEs) are enzymes that can convert the prodrug CPT-11 (irinotecan) to its active metabolite SN-38, a potent topoisomerase I inhibitor. We have adenovirally transduced an established clonal human NSC line (HB1.F3.CD) to express a rabbit carboxylesterase (rCE) or a modified human CE (hCE1m6), which are more effective at converting CPT-11 to SN-38 than endogenous human CE. We hypothesized that NSC-mediated CE/CPT-11 therapy would allow tumor-localized production of SN-38 and significantly increase the therapeutic efficacy of irinotecan. Here, we report that transduced NSCs transiently expressed high levels of active CE enzymes, retained their tumor-tropic properties, and mediated an increase in the cytotoxicity of CPT-11 toward glioma cells. CE-expressing NSCs (NSC.CEs), whether administered intracranially or intravenously, delivered CE to orthotopic human glioma xenografts in mice. NSC-delivered CE catalyzed conversion of CPT-11 to SN-38 locally at tumor sites. These studies demonstrate the feasibility of NSC-mediated delivery of CE to glioma and lay the foundation for translational studies of this therapeutic paradigm to improve clinical outcome and quality of life in patients with malignant brain tumors. PMID:24167321

  2. Altered features and increased chemosensitivity of human breast cancer cells mediated by adipose tissue-derived mesenchymal stromal cells

    PubMed Central

    2013-01-01

    Background 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. Methods 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. Results 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. Conclusions 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. PMID:24209831

  3. HLA-A11-mediated protection from NK cell-mediated lysis: role of HLA-A11-presented peptides.

    PubMed

    Gavioli, R; Zhang, Q J; Masucci, M G

    1996-08-01

    The capacity of MHC class I to protect target cells from NK is well established, but the mechanism by which these molecules influence NK recognition and the physical properties associated with this function remain poorly defined. We have examined this issue using as a model the HLA-A11 allele. HLA-A11 expression correlated with reduced susceptibility to NK and interferon-activated cytotoxicity in transfected sublines of the A11-defective Burkitt's lymphoma WW2-BL and the HLA class I A,B-null C1R cell line. Protection was also achieved by transfection of HLA-A11 in the peptide processing mutant T2 cells line (T2/A11), despite a very low expression of the transfected product at the cell surface. Induction of surface HLA-A11 by culture of T2/A11 cells at 26 degrees C or in the presence of beta 2m did not affect lysis, whereas NK sensitivity was restored by culture in the presence of HLA-All-binding synthetic peptides derived from viral or cellular proteins. Acid treatment rendered T2/A11 and C1R/A11 cells sensitive to lysis, but protection was restored after preincubation with peptide preparations derived from surface stripping of T2/A11 cells. Similar peptide preparations from T2 cells had no effect. The results suggest that NK protection is mediated by HLA-A11 molecules carrying a particular set of peptides that are translocated to the site of MHC class I assembly in the ER in a TAP-independent fashion. PMID:8839770

  4. Initial cytotoxicity of novel titanium alloys.

    PubMed

    Koike, M; Lockwood, P E; Wataha, J C; Okabe, T

    2007-11-01

    We assessed the biological response to several novel titanium alloys that have promising physical properties for biomedical applications. Four commercial titanium alloys [Super-TIX(R) 800, Super-TIX(R) 51AF, TIMETAL(R) 21SRx, and Ti-6Al-4V (ASTM grade 5)] and three experimental titanium alloys [Ti-13Cr-3Cu, Ti-1.5Si and Ti-1.5Si-5Cu] were tested. Specimens (n = 6; 5.0 x 5.0 x 3.0 mm(3)) were cast in a centrifugal casting machine using a MgO-based investment and polished to 600 grit, removing 250 mum from each surface. Commercially pure titanium (CP Ti: ASTM grade 2) and Teflon (polytetrafluoroethylene) were used as positive controls. The specimens were cleaned and disinfected, and then each cleaned specimen was placed in direct contact with Balb/c 3T3 fibroblasts for 72 h. The cytotoxicity [succinic dehydrogenase (SDH) activity] of the extracts was assessed using the MTT method. Cytotoxicity of the metals tested was not statistically different compared to the CP Ti and Teflon controls (p > 0.05). These novel titanium alloys pose cytotoxic risks no greater than many other commonly used alloys, including commercially pure titanium. The promising short-term biocompatibility of these Ti alloys is probably due to their excellent corrosion resistance under static conditions, even in biological environments. PMID:17385227

  5. Iron oxide nanoparticle enhancement of radiation cytotoxicity

    NASA Astrophysics Data System (ADS)

    Mazur, Courtney M.; Tate, Jennifer A.; Strawbridge, Rendall R.; Gladstone, David J.; Hoopes, P. Jack

    2013-02-01

    Iron oxide nanoparticles (IONPs) have been investigated as a promising means for inducing tumor cell-specific hyperthermia. Although the ability to generate and use nanoparticles that are biocompatible, tumor specific, and have the ability to produce adequate cytotoxic heat is very promising, significant preclinical and clinical development will be required for clinical efficacy. At this time it appears using IONP-induced hyperthermia as an adjunct to conventional cancer therapeutics, rather than as an independent treatment, will provide the initial IONP clinical treatment. Due to their high-Z characteristics, another option is to use intracellular IONPs to enhance radiation therapy without excitation with AMF (production of heat). To test this concept IONPs were added to cell culture media at a concentration of 0.2 mg Fe/mL and incubated with murine breast adenocarcinoma (MTG-B) cells for either 48 or 72 hours. Extracellular iron was then removed and all cells were irradiated at 4 Gy. Although samples incubated with IONPs for 48 hrs did not demonstrate enhanced post-irradiation cytotoxicity as compared to the non-IONP-containing cells, cells incubated with IONPs for 72 hours, which contained 40% more Fe than 48 hr incubated cells, showed a 25% decrease in clonogenic survival compared to their non-IONP-containing counterparts. These results suggest that a critical concentration of intracellular IONPs is necessary for enhancing radiation cytotoxicity.

  6. Mutagenic and cytotoxic activities of benfuracarb insecticide.

    PubMed

    Eren, Yasin; Erdoğmuş, Sevim Feyza; Akyıl, Dilek; Özkara, Arzu

    2016-08-01

    Benfuracarb is a carbamate insecticide used to control insect pests in vegetables and it has anti-acetylcholinesterase activity lower than other carbamates. Cytotoxic effects of benfuracarb were evaluated by using root growth inhibition (EC50), mitotic index (MI), and mitotic phase determinations on the root meristem cells of Allium cepa and mutagenic effects were determined in Salmonella typhymurium Ames test by TA98 and TA100 strains with and without metabolic activation. In Allium test, 1 % DMSO was used as negative control group and 10 ppm MMS was used as positive control group. 75 ppm concentration of benfuracarb was found as EC50. In MI and mitotic phases determination study, 37.5, 75 and 150 ppm doses of benfuracarb were used. Dose-dependent cytotoxic activity was found by root growth inhibition and MI studies. It was identified that mitotic inhibition activity of benfuracarb was higher than 10 ppm MMS. In Ames test, mutagenic activity was not observed and over 200 µg/plate of benfuracarb was determined as cytotoxic to S. typhymurium strains. Benfuracarb can be called as "mitotic inhibitor" but not called as mutagen. PMID:25381170

  7. Recombinant Bivalent Fusion Protein rVE Induces CD4+ and CD8+ T-Cell Mediated Memory Immune Response for Protection Against Yersinia enterocolitica Infection

    PubMed Central

    Singh, Amit K.; Kingston, Joseph J.; Gupta, Shishir K.; Batra, Harsh V.

    2015-01-01

    Studies investigating the correlates of immune protection against Yersinia infection have established that both humoral and cell mediated immune responses are required for the comprehensive protection. In our previous study, we established that the bivalent fusion protein (rVE) comprising immunologically active regions of Y. pestis LcrV (100–270 aa) and YopE (50–213 aa) proteins conferred complete passive and active protection against lethal Y. enterocolitica 8081 challenge. In the present study, cohort of BALB/c mice immunized with rVE or its component proteins rV, rE were assessed for cell mediated immune responses and memory immune protection against Y. enterocolitica 8081. rVE immunization resulted in extensive proliferation of both CD4 and CD8 T cell subsets; significantly high antibody titer with balanced IgG1: IgG2a/IgG2b isotypes (1:1 ratio) and up-regulation of both Th1 (TNF-α, IFN-γ, IL-2, and IL-12) and Th2 (IL-4) cytokines. On the other hand, rV immunization resulted in Th2 biased IgG response (11:1 ratio) and proliferation of CD4+ T-cell; rE group of mice exhibited considerably lower serum antibody titer with predominant Th1 response (1:3 ratio) and CD8+ T-cell proliferation. Comprehensive protection with superior survival (100%) was observed among rVE immunized mice when compared to the significantly lower survival rates among rE (37.5%) and rV (25%) groups when IP challenged with Y. enterocolitica 8081 after 120 days of immunization. Findings in this and our earlier studies define the bivalent fusion protein rVE as a potent candidate vaccine molecule with the capability to concurrently stimulate humoral and cell mediated immune responses and a proof of concept for developing efficient subunit vaccines against Gram negative facultative intracellular bacterial pathogens. PMID:26733956

  8. Impaired antibody-dependent cellular cytotoxicity mediated by herceptin in patients with gastric cancer.

    PubMed

    Kono, Koji; Takahashi, Akihiro; Ichihara, Fumiko; Sugai, Hidemitsu; Fujii, Hideki; Matsumoto, Yoshirou

    2002-10-15

    The humanized monoclonal antibody Herceptin, which specifically targets HER-2/neu, exhibits growth inhibitory activity against HER-2/neu-overexpressing tumors and is approved for therapeutic use with proved survival benefit in patients with HER-2/neu-positive breast cancer. In the present study, we investigated whether Herceptin could affect the HER-2/neu-overexpressing gastric cancer cells based on antibody-dependent cell-mediated cytotoxicity (ADCC) and compared immune effector cells from gastric cancer patients with normal individuals on ADCC. HER-2/neu-expressing gastric cancer cells could be killed by Herceptin-mediated ADCC and the Herceptin-induced ADCC correlated with the degree of HER-2/neu expression on the gastric cancer cells. However, the Herceptin-mediated ADCC was significantly impaired in peripheral blood mononuclear cells from advanced disease patients (n = 10) compared with that in early disease (n = 12; P = 0.04) or healthy individuals (n = 10, P = 0.02). Moreover, natural killer (NK) cells purified from patients with advanced disease indicated less Herceptin-mediated ADCC in comparison with that from healthy donors (P = 0.04), whereas monocytes purified from the patients showed an almost equal amount of Herceptin-mediated ADCC in comparison with that from healthy individuals, indicating that NK cell dysfunction contributed to the impaired Herceptin-mediated ADCC in gastric cancer patients. Furthermore, the NK-cell dysfunction on Herceptin-mediated ADCC correlated with the down-regulation of CD16zeta expression in the patients, and interleukin 2 ex vivo treatment of NK cells could restore the impairment of Herceptin-mediated ADCC, concomitant to the normalization of the expression of CD16zeta molecules. Thus, some modalities such as interleukin 2 treatment aimed at reversing NK dysfunction may be necessary for successful Herceptin treatment of gastric cancer. PMID:12384543

  9. Cellular cytotoxicity mediated by isotype-switch variants of a monoclonal antibody to human neuroblastoma.

    PubMed Central

    d'Uscio, C. H.; Jungi, T. W.; Blaser, K.

    1991-01-01

    The biological property of an antibody is determined by its antigen binding characteristics and its isotype-related effector functions. We have established monoclonal antibodies of different isotypes by stepwise selection and cloning of the hybridoma CE7. The original CE7 secretes an IgG1/kappa (CE7 gamma 1) antibody that recognises a 185 kD cell surface glycoprotein expressed on all human sympatho-adrenomedullary cells. Isotype-switch variants were isolated in the following sequence: from the original CE7 gamma 1, CE7 gamma 2b variants were isolated, and from a CE7 gamma 2b variant CE7 gamma 2a variants were isolated. The antibodies of three different isotype variant cell lines possess identical antigen binding characteristics, but display distinct effector functions as demonstrated by antibody dependent cell-mediated cytotoxicity (ADCC). ADCC was performed with the neuroblastoma line IMR-32 as the target cells, and different FcR gamma positive cells were either freshly isolated from human peripheral blood leukocytes or cultured for 6-10 days and tested as potential effector cells. Tumour lysis mediated by monocyte-derived macrophages depended on the presence of CE7 gamma 2a antibodies; antibodies from the CE7 hybridomas of gamma 2b and gamma 1 isotypes were virtually inactive in ADCC assay. Pre-exposure of macrophages to rIFN-gamma enhanced their ADCC activity, a result that is compatible with the notion that the high affinity Fc IgG receptor (FcR gamma I/CD64) is involved in the triggering of ADCC in macrophages. In contrast to macrophages, mononuclear cells, nonadherent cells and monocytes displayed considerable non-specific lytic activity, which was little influenced by the presence of antibody regardless of the isotype added. PMID:1911183

  10. Cord Blood Stem Cell-Mediated Induction of Apoptosis in Glioma Downregulates X-Linked Inhibitor of Apoptosis Protein (XIAP)

    PubMed Central

    Dasari, Venkata Ramesh; Velpula, Kiran Kumar; Kaur, Kiranpreet; Fassett, Daniel; Klopfenstein, Jeffrey D.; Dinh, Dzung H.; Gujrati, Meena; Rao, Jasti S.

    2010-01-01

    Background 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. Methodology/Principal Findings 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. Conclusions/Significance 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

  11. Serglycin determines secretory granule repertoire and regulates natural killer cell and cytotoxic T lymphocyte cytotoxicity.

    PubMed

    Sutton, Vivien R; Brennan, Amelia J; Ellis, Sarah; Danne, Jill; Thia, Kevin; Jenkins, Misty R; Voskoboinik, Ilia; Pejler, Gunnar; Johnstone, Ricky W; Andrews, Daniel M; Trapani, Joseph A

    2016-03-01

    The anionic proteoglycan serglycin is a major constituent of secretory granules in cytotoxic T lymphocyte (CTL)/natural killer (NK) cells, and is proposed to promote the safe storage of the mostly cationic granule toxins, granzymes and perforin. Despite the extensive defects of mast cell function reported in serglycin gene-disrupted mice, no comprehensive study of physiologically relevant CTL/NK cell populations has been reported. We show that the cytotoxicity of serglycin-deficient CTL and NK cells is severely compromised but can be partly compensated in both cell types when they become activated. Reduced intracellular granzyme B levels were noted, particularly in CD27(+) CD11b(+) mature NK cells, whereas serglycin(-/-) TCR-transgenic (OTI) CD8 T cells also had reduced perforin stores. Culture supernatants from serglycin(-/-) OTI T cells and interleukin-2-activated NK contained increased granzyme B, linking reduced storage with heightened export. By contrast, granzyme A was not significantly reduced in cells lacking serglycin, indicating differentially regulated trafficking and/or storage for the two granzymes. A quantitative analysis of different granule classes by transmission electronmicroscopy showed a selective loss of dense-core granules in serglycin(-/-) CD8(+) CTLs, although other granule types were maintained quantitatively. The findings of the present study show that serglycin plays a critical role in the maturation of dense-core cytotoxic granules in cytotoxic lymphocytes and the trafficking and storage of perforin and granzyme B, whereas granzyme A is unaffected. The skewed retention of cytotoxic effector molecules markedly reduces CTL/NK cell cytotoxicity, although this is partly compensated for as a result of activating the cells by physiological means. PMID:26756195

  12. DNA vaccine cocktail expressing genotype A and C HBV surface and consensus core antigens generates robust cytotoxic and antibody responses in mice and Rhesus macaques.

    PubMed

    Obeng-Adjei, N; Hutnick, N A; Yan, J; Chu, J S; Myles, D J F; Morrow, M P; Sardesai, N Y; Weiner, D B

    2013-12-01

    There are well over a quarter of a billion chronic hepatitis B virus (HBV) carriers across the globe. Most carriers are at high risk for development of liver cirrhosis and subsequent progression to hepatocellular carcinoma. It is therefore imperative to develop new approaches for immunotherapy against this infection. Antibodies and cytotoxic T cells to different HBV antigens are believed to be important for reducing viral load and clearing HBV-infected cells from the liver. Some of the major challenges facing current vaccine candidates have been their inability to induce both humoral and cellular immunity to multiple antigenic targets and the induction of potent immune responses against the major genotypes of HBV. In this study, highly optimized synthetic DNA plasmids against the HBV consensus core (HBc) and surface (HBs) antigens genotypes A and C were developed and evaluated for their immune potential. These plasmids, which encode the most prevalent genotypes of the virus, were observed to individually induce binding antibodies to HBs antigens and drove robust cell-mediated immunity in animal models. Similar responses to both HBc and HBs antigens were observed when mice and non-human primates were inoculated with the HBc-HBs cocktails. In addition to the cytotoxic T lymphocyte activities exhibited by the immunized mice, the vaccine-induced responses were broadly distributed across multiple antigenic epitopes. These elements are believed to be important to develop an effective therapeutic vaccine. These data support further evaluation of multivalent synthetic plasmids as therapeutic HBV vaccines. PMID:24310062

  13. Novel CD8(+) cytotoxic T cell epitopes in bovine leukemia virus with cattle.

    PubMed

    Bai, Lanlan; Takeshima, Shin-Nosuke; Isogai, Emiko; Kohara, Junko; Aida, Yoko

    2015-12-16

    Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T cell leukemia virus (HTLV). The cytotoxic T lymphocyte (CTL) plays a key role in suppressing the progression of disease caused by BLV. T and B cell epitopes in BLV have been studied, but CD8(+) CTL epitopes remain poorly understood. We used a library of 115 synthetic peptides covering the entirety of the Env proteins (gp51 and gp30), the Gag proteins (p15, p24, and p12), and the Tax protein of BLV to identify 11 novel CD8(+) T cell epitopes (gp51N5, gp51N11, gp51N12, gp30N5, gp30N6, gp30N8, gp30N16, tax16, tax18, tax19, and tax20) in four calves experimentally infected with BLV. The number of CD8(+) T cell epitopes that could be identified in each calf correlated with the BLV proviral load. Interestingly, among the 11 epitopes identified, only gp51N11 was capable of inducing CD8(+) T cell-mediated cytotoxicity in all four calves, but it is not a suitable vaccine target because it shows a high degree of polymorphism according to the Wu-Kabat variability index. By contrast, no CTL epitopes were identified from the Gag structural protein. In addition, several epitopes were obtained from gp30 and Tax, indicating that cellular immunity against BLV is strongly targeted to these proteins. CD8(+) CTL epitopes from gp30 and Tax were less polymorphic than epitopes from. Indeed, peptides tax16, tax18, tax19, and tax20 include a leucine-rich activation domain that encompasses a transcriptional activation domain, and the gp30N16 peptide contains a proline-rich region that interacts with a protein tyrosine phosphatase SHP1 to regulate B cell activation. Moreover, at least one CD8(+) CTL epitope derived from gp30 was identified in each of the four calves. These results indicate that BLV gp30 may be the best candidate for the development of a BLV vaccine. PMID:26552001

  14. Cell-mediated and humoral immune responses induced by scarification vaccination of human volunteers with a new lot of the live vaccine strain of Francisella tularensis.

    PubMed Central

    Waag, D M; Galloway, A; Sandstrom, G; Bolt, C R; England, M J; Nelson, G O; Williams, J C

    1992-01-01

    Tularemia is a disease caused by the facultative intracellular bacterium Francisella tularensis. We evaluated a new lot of live F. tularensis vaccine for its immunogenicity in human volunteers. Scarification vaccination induced humoral and cell-mediated immune responses. Indications of a positive immune response after vaccination included an increase in specific antibody levels, which were measured by enzyme-linked immunosorbent and immunoblot assays, and the ability of peripheral blood lymphocytes to respond to whole F. tularensis bacteria as recall antigens. Vaccination caused a significant rise (P less than 0.05) in immunoglobulin A (IgA), IgG, and IgM titers. Lymphocyte stimulation indices were significantly increased (P less than 0.01) in vaccinees 14 days after vaccination. These data verify that this new lot of live F. tularensis vaccine is immunogenic. Images PMID:1400988

  15. Erlotinib inhibits T-cell-mediated immune response via down-regulation of the c-Raf/ERK cascade and Akt signaling pathway

    SciTech Connect

    Luo Qiong; Gu Yanhong; Zheng Wei; Wu Xingxin; Gong Fangyuan; Gu Liyun; Sun Yang; Xu Qiang

    2011-03-01

    Erlotinib is a potent inhibitor of epidermal growth factor receptor tyrosine kinase and has been demonstrated to treat advanced or metastatic non-small cell lung cancer to prolong survival after failure of first-line or second-line chemotherapy. However, little is known about its effects on immune system. In the present study, we aimed to investigate the immunosuppressive activity of erlotinib on T lymphocytes both in vitro and in vivo, and further explore its potential molecular mechanism. Erlotinib exerted a significant inhibition on the T cell proliferation and activation induced by concanavalin A, anti-CD3 plus anti-CD28, staphylococcal enterotoxin B or phorbol myristate acetate respectively in a concentration-dependent manner and it also inhibited the secretion of the proinflammatory cytokines such as IL-2 and IFN-{gamma} of activated T cells. Further study showed that erlotinib caused G0/G1 arrest and suppressed the phosphorylations of c-Raf, ERK and Akt in activated T cells. Moreover, erlotinib significantly ameliorated picryl chloride-induced ear contact dermatitis in a dose-dependent manner in vivo. In summary, these findings suggest that erlotinib may cause the impairment of T-cell-mediated immune response both in vitro and in vivo through inhibiting T cell proliferation and activation, which is closely associated with its potent down-regulation of the c-Raf/ERK cascade and Akt signaling pathway. - Graphical abstract: Erlotinib may cause the impairment of T-cell-mediated immune response both in vitro and in vivo through inhibiting T cell proliferation and activation, which is closely associated with its potent down-regulation of the c-Raf/ERK cascade and Akt signaling pathway. Display Omitted

  16. Inhibitors of histone deacetylase 1 reverse the immune evasion phenotype to enhance T-cell mediated lysis of prostate and breast carcinoma cells.

    PubMed

    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. PMID:26862729

  17. Inhibitors of histone deacetylase 1 reverse the immune evasion phenotype to enhance T-cell mediated lysis of prostate and breast carcinoma cells

    PubMed Central

    Gameiro, Sofia R.; Malamas, Anthony S.; Tsang, Kwong Y.; Ferrone, Soldano; Hodge, James W.

    2016-01-01

    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. PMID:26862729

  18. Depression of Complement Regulatory Factors in Rat and Human Renal Grafts Is Associated with the Progress of Acute T-Cell Mediated Rejection

    PubMed Central

    Yamanaka, Kazuaki; Kakuta, Yoichi; Miyagawa, Shuji; Nakazawa, Shigeaki; Kato, Taigo; Abe, Toyofumi; Imamura, Ryoichi; Okumi, Masayoshi; Maeda, Akira; Okuyama, Hiroomi; Mizuno, Masashi; Nonomura, Norio

    2016-01-01

    Background 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. Methods 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. Results 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. Conclusions 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. PMID:26928779

  19. Structure of the Human Activating Natural Cytotoxicity Receptor NKp30 Bound to its Tumor Cell Ligand B7-H6

    SciTech Connect

    Y Li; Q Wang; R Mariuzza

    2011-12-31

    Natural killer (NK) cells are lymphocytes of the innate immune system that participate in the elimination of tumor cells. In humans, the activating natural cytotoxicity receptors (NCRs) NKp30, NKp44, and NKp46 play a major role in NK cell-mediated tumor cell lysis. NKp30 recognizes B7-H6, a member of the B7 family which is expressed on tumor, but not healthy, cells. To understand the basis for tumor surveillance by NCRs, we determined the structure of NKp30, a member of the CD28 family which includes CTLA-4 and PD-1, in complex with B7-H6. The overall organization of the NKp30-B7-H6-activating complex differs considerably from those of the CTLA-4-B7 and PD-1-PD-L T cell inhibitory complexes. Whereas CTLA-4 and PD-1 use only the front {beta}-sheet of their Ig-like domain to bind ligands, NKp30 uses both front and back {beta}-sheets, resulting in engagement of B7-H6 via the side, as well as face, of the {beta}-sandwich. Moreover, B7-H6 contacts NKp30 through the complementarity-determining region (CDR) - like loops of its V-like domain in an antibody-like interaction that is not observed for B7 or PD-L. This first structure of an NCR bound to ligand provides a template for designing molecules to stimulate NKp30-mediated cytolytic activity for tumor immunotherapy.

  20. Identification of cytotoxic T lymphocyte epitopes on swine viruses: multi-epitope design for universal T cell vaccine.

    PubMed

    Liao, Yu-Chieh; Lin, Hsin-Hung; Lin, Chieh-Hua; Chung, Wen-Bin

    2013-01-01

    Classical swine fever (CSF), foot-and-mouth disease (FMD) and porcine reproductive and respiratory syndrome (PRRS) are the primary diseases affecting the pig industry globally. Vaccine induced CD8(+) T cell-mediated immune response might be long-lived and cross-serotype and thus deserve further attention. Although large panels of synthetic overlapping peptides spanning the entire length of the polyproteins of a virus facilitate the detection of cytotoxic T lymphocyte (CTL) epitopes, it is an exceedingly costly and cumbersome approach. Alternatively, computational predictions have been proven to be of satisfactory accuracy and are easily performed. Such a method enables the systematic identification of genome-wide CTL epitopes by incorporating epitope prediction tools in analyzing large numbers of viral sequences. In this study, we have implemented an integrated bioinformatics pipeline for the identification of CTL epitopes of swine viruses including the CSF virus (CSFV), FMD virus (FMDV) and PRRS virus (PRRSV) and assembled these epitopes on a web resource to facilitate vaccine design. Identification of epitopes for cross protections to different subtypes of virus are also reported in this study and may be useful for the development of a universal vaccine against such viral infections among the swine population. The CTL epitopes identified in this study have been evaluated in silico and possibly provide more and wider protection in compared to traditional single-reference vaccine design. The web resource is free and open to all users through http://sb.nhri.org.tw/ICES. PMID:24358361

  1. Inhibitory effects of various oxygenated sterols on the differentiation and function of tumor-specific cytotoxic T lymphocytes

    SciTech Connect

    Spangrude, G.J.; Sherris, D.; Daynes, R.A.

    1982-05-01

    Irradiation of skin with ultraviolet light (UVL) is capable of causing many biological and biochemical changes in this complex organ. One early consequence is the oxidation of epidermal plasma membrane cholesterol, causing the induction of a wide variety of photoproducts. It is well recognized that some oxygenated sterols possess potent biological activity on mammalian cells by their ability to inhibit endogeneous mevalonate and cholesterol biosynthesis. In the few immunological systems that have been studied, there is general agreement that lymphocyte function is altered in the presence of certain oxygenated sterols. Insight into the biochemical basis for altered lymphocyte function is lacking, as both afferent and efferent blockades have been suggested. These studies were undertaken to determine the effect of various oxygenated sterols (representing a number of known cholesterol-derived photoproducts) on the generation (afferent) and function (efferent) of cytotoxic T lymphocytes (CTLs). Cell-mediated immune responses which result in the generation of both alloantigen-specific and syngeneic tumor-specific CTLs were evaluated. (JMT)

  2. Cytotoxic activities of several geranyl-substituted flavanones.

    PubMed

    Smejkal, Karel; Svacinová, Jana; Slapetová, Tereza; Schneiderová, Kristýna; Dall'acqua, Stefano; Innocenti, Gabbriella; Závalová, Veronika; Kollár, Peter; Chudík, Stanislav; Marek, Radek; Julínek, Ondrej; Urbanová, Marie; Kartal, Murat; Csöllei, Marek; Dolezal, Karel

    2010-04-23

    Nine geranylated flavanones isolated from the fruits of Paulownia tomentosa (4-12) and two from the roots of Morus alba (13 and 14) were examined for cytotoxicity to selected human cancer cell lines and normal human fibroblasts. Cytotoxicity was determined in vitro using a calcein AM cytotoxicity assay. Cytotoxicity for the THP-1 monocytic leukemia cell line was tested using erythrosin B cell staining. The geranylated compounds tested were compared with the known simple flavanone standards taxifolin (1), naringenin (2), and hesperetin (3) and with the standard anticancer drugs olomoucine II, diaziquone, and oxaliplatin and the antineoplastic compound camptothecin, and showed different levels of cytotoxicity. The effects of structural changes on cytotoxic activity, including geranyl substitution of the flavanone skeleton and the oxidation pattern of ring B of the flavanones, are discussed. PMID:20192247

  3. Lectin-dependent neutrophil-mediated cytotoxicity. I. Characteristics.

    PubMed Central

    Simchowitz, L; Schur, P H

    1976-01-01

    Isolated normal human peripheral neutrophils became cytotoxic to chicken red blood cells (CRBC) in the presence of phytohaemagglutinin (PHA) and concanavalin A (Con A), a phenomenon which we have termed lectin-dependent neutrophilmediated cytotoxicity (LDNMC). Substantial cytotoxicity could be demonstrated by 1 h of incubation at 37 degrees. Isolated human peripheral lymphocytes were not cytotoxic to CRBC in the presence of these lectins, even after 18 h of incubation. Both PHA and Con A exhibited dose responses over a wide concentration range and displayed progressive, time-dependent cytotoxicity. Cytotoxicity for both PHA and Con A was greater at 37 degrees than at 22 degrees, and was undetectable at 4 degrees. CRBC as target cells were much more readily lysed than either sheep or human erythrocytes. Erythrophagocytosis did not appear to play a role. Images Figure 1 PMID:955680

  4. Cytotoxic Effects of Fucoidan Nanoparticles against Osteosarcoma

    PubMed Central

    Kimura, Ryuichiro; Rokkaku, Takayoshi; Takeda, Shinji; Senba, Masachika; Mori, Naoki

    2013-01-01

    In this study, we analyzed the size-dependent bioactivities of fucoidan by comparing the cytotoxic effects of native fucoidan and fucoidan lipid nanoparticles on osteosarcoma in vitro and in vivo. In vitro experiments indicated that nanoparticle fucoidan induced apoptosis of an osteosarcoma cell line more efficiently than native fucoidan. The more potent effects of nanoparticle fucoidan, relative to native fucoidan, were confirmed in vivo using a xenograft osteosarcoma model. Caco-2 cell transport studies showed that permeation of nanoparticle fucoidan was higher than native fucoidan. The higher bioactivity and superior bioavailability of nanoparticle fucoidan could potentially be utilized to develop novel therapies for osteosarcoma. PMID:24177673

  5. Cytotoxic constituents of the lichen Diploicia canescens.

    PubMed

    Millot, Marion; Tomasi, Sophie; Studzinska, Elisabeth; Rouaud, Isabelle; Boustie, Joël

    2009-12-01

    A new diphenyl ether (1), along with 12 known compounds, was isolated from the lichen Diploicia canescens. The structure of compound 1 was elucidated by spectroscopic data analysis, and the biosynthetic origin of this product is discussed. Secalonic acids B (7), D (8), and F (9) were isolated for the first time from D. canescens. The cytotoxic activities of 1-3, 6-8, and 10 against the B16 murine melanoma and HaCaT human keratinocyte cell lines were evaluated. PMID:19919064

  6. Cytotoxic Polyisoprenyl Benzophenonoids from Garcinia subelliptica

    PubMed Central

    Zhang, Li-Jie; Chiou, Chun-Tang; Cheng, Jing-Jy; Huang, Hui-Chi; Yang Kuo, Li-Ming; Liao, Chia-Chin; Bastow, Kenneth F.; Lee, Kuo-Hsiung; Kuo, Yao-Haur

    2010-01-01

    Six new polyisoprenyl benzophenonoids, (±)-garcinialiptone A (1, 2), garcinialiptone B (3), (−)-cycloxanthochymol (4), garcinialiptone C (5), and garcinialiptone D (6), along with three known compounds, xanthochymol (7), isoxanthochymol (8), and cycloxanthochymol (9), were isolated from the fruits of Garcinia subelliptica. The structures of 1–6 were elucidated by spectroscopic analysis. Biological evaluation showed that all compounds 1–9 exhibited cytotoxic activity against a small panel of human tumor cell lines (A549, DU145, KB, vincristine-resistant KB). PMID:20232858

  7. Cytotoxic phorbol esters of Croton tiglium.

    PubMed

    Zhang, Xiao-Long; Wang, Lun; Li, Fu; Yu, Kai; Wang, Ming-Kui

    2013-05-24

    Chemical investigation of the seeds of Croton tiglium afforded eight new phorbol diesters (three phorbol diesters, 1-3, and five 4-deoxy-4α-phorbol diesters, 4-8), together with 11 known phorbol diesters (nine phorbol diesters, 9-17, and two 4-deoxy-4α-phorbol diesters, 18 and 19). The structures of compounds 1-8 were determined by spectroscopic data information and chemical degradation experiments. The cytotoxic activities of the phorbol diesters were evaluated against the SNU387 hepatic tumor cell line, and compound 3 exhibited the most potent activity (IC50 1.2 μM). PMID:23701597

  8. New Cytotoxic Tigliane Diterpenoids from Croton caudatus.

    PubMed

    Chen, Ying-Ying; Yang, Kun-Xian; Yang, Xing-Wei; Khan, Afsar; Liu, Lu; Wang, Bei; Zhao, Yun-Li; Liu, Ya-Ping; Li, Yan; Luo, Xiao-Dong

    2016-05-01

    Three new tigliane-type diterpenoids were isolated from the methanolic extract of the twigs and leaves of Croton caudatus, trivially named crotusins A-C (1-3). The structures of compounds 1-3 were elucidated on the basis of extensive spectral methods. These new compounds were highly oxygenated and heavily substituted. Cytotoxic activity against five human tumor cell lines was assessed for compounds 1-3 of which compound 3 showed significant inhibitory activity with IC50 values ranging from 0.49 to 4.19 µM against these cells, while crotusins A and B exhibited moderate activity. PMID:27002392

  9. Synthesis and cytotoxic evaluation of combretafurazans.

    PubMed

    Tron, Gian Cesare; Pagliai, Francesca; Del Grosso, Erika; Genazzani, Armando A; Sorba, Giovanni

    2005-05-01

    Combretastatin A-4 is an antitumoral and antitubulin agent that is active only in its cis configuration. In the present manuscript, we have synthesized cis-locked combretastatins embodying a furazan ring (combretafurazans). To achieve this, we have developed a new strategy that exploits the dehydration of vicinal dioximes using the Mitsunobu reaction. Among the advantages of following such a strategy are the mild conditions used for the construction of the diarylfurazan derivatives, allowing for the presence of highly functionalized substrates and deactivated aromatic rings. Combretafurazans are more potent in vitro cytotoxic compounds compared to combretastatins in neuroblastoma cells, yet maintaining similar structure-activity relationship and pharmacodynamic profiles. PMID:15857132

  10. CALOTROPIN, A CYTOTOXIC PRINCIPLE ISOLATED FROM ASCLEPIAS CURASSAVICA L.

    PubMed

    KUPCHAN, S M; KNOX, J R; KELSEY, J E; SAENZRENAULD, J A

    1964-12-25

    An alcoholic extract of Asclepias curassavica L., a plant widely used in folk medicine for treating cancer and warts, shows cytotoxic activity when tested in vitro against cells derived from human carcinoma of the nasopharynx. Systematic fractionation of the extract has led to isolation and characterization of calotropin as a cytotoxic principle. Calotropin is similar in structure to two cardiac glycosides recently shown to be responsible for the cytotoxicity of Apocynum cannabinum L. PMID:14224519

  11. In vitro cytotoxicity of metallic ions released from dental alloys.

    PubMed

    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. PMID:25549610

  12. Variant antigenic peptide promotes cytotoxic T lymphocyte adhesion to target cells without cytotoxicity

    PubMed Central

    Shotton, David M.; Attaran, Amir

    1998-01-01

    Timelapse video microscopy has been used to record the motility and dynamic interactions between an H-2Db-restricted murine cytotoxic T lymphocyte clone (F5) and Db-transfected L929 mouse fibroblasts (LDb) presenting normal or variant antigenic peptides from human influenza nucleoprotein. F5 cells will kill LDb target cells presenting specific antigen (peptide NP68: ASNENMDAM) after “browsing” their surfaces for between 8 min and many hours. Cell death is characterized by abrupt cellular rounding followed by zeiosis (vigorous “boiling” of the cytoplasm and blebbing of the plasma membrane) for 10–20 min, with subsequent cessation of all activity. Departure of cytotoxic T lymphocytes from unkilled target cells is rare, whereas serial killing is sometimes observed. In the absence of antigenic peptide, cytotoxic T lymphocytes browse target cells for much shorter periods, and readily leave to encounter other targets, while never causing target cell death. Two variant antigenic peptides, differing in nonamer position 7 or 8, also act as antigens, albeit with lower efficiency. A third variant peptide NP34 (ASNENMETM), which differs from NP68 in both positions and yet still binds Db, does not stimulate F5 cytotoxicity. Nevertheless, timelapse video analysis shows that NP34 leads to a significant modification of cell behavior, by up-regulating F5–LDb adhesive interactions. These data extend recent studies showing that partial agonists may elicit a subset of the T cell responses associated with full antigen stimulation, by demonstrating that TCR interaction with variant peptide antigens can trigger target cell adhesion and surface exploration without activating the signaling pathway that results in cytotoxicity. PMID:9861010

  13. Preparing cytotoxic agents in an isolator.

    PubMed

    Favier, M; Hansel, S; Bressolle, F

    1993-11-01

    The design of an isolator and its use by an oncology satellite pharmacy for preparing cytotoxic drugs are described. The isolator (Iso Concept, Boulogne, France) is a totally enclosed ventilated biological-safety cabinet of class III polyvinyl chloride (PVC) with positive air pressure, a half-suit with a rotating seal, and attached neoprene gloves. There are three work-stations, one for the half-suit and two along one side of the isolator. The ventilation and air filtration system consists of one entry pipe with a full ventilation-filtration box fitted with one prefilter, one blower, one ball valve, one high-efficiency particulate air (HEPA) filter, one airtight nipple connected to an automatic sterilizer, alarms, and one exhaust pipe protected by a HEPA filter. The air lock consists of a rigid, transparent Plexiglas pass-through. The chamber is sterilized with heated compressed air mixed with 3.5% peracetic acid. Maintenance includes regular changing of gloves and HEPA filters; checking of the integrity of the PVC, half-suit, and gloves; and washing and decontamination procedures. Preparation of cytotoxics is planned in advance with prescription data and manufacturing sheets. In the half-suit, a pharmacy technician reads the label, supervises preparation of the sterile admixture, and writes a label. The operators on the side of the unit read the manufacturing sheet and prepare the dose identified by the label.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8266957

  14. Cytotoxic isoferulic acidamide from Myricaria germanica (Tamaricaceae)

    PubMed Central

    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- 1H and 13C 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 IC50''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. PMID:23123452

  15. Study of Cytotoxic Effects of Benzonitrile Pesticides

    PubMed Central

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

    2015-01-01

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

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

    PubMed

    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. PMID:23123452

  17. Study of Cytotoxic Effects of Benzonitrile Pesticides.

    PubMed

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

    2015-01-01

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

  18. Cytotoxicity of occupationally and environmentally relevant mycotoxins.

    PubMed

    Bünger, Jürgen; Westphal, Götz; Mönnich, Angelika; Hinnendahl, Britta; Hallier, Ernst; Müller, Michael

    2004-10-01

    Mycotoxins can cause various toxic effects in humans. Acute and chronic respiratory diseases were reported after inhalation of organic dust containing toxigenic moulds and mycotoxins, respectively. To gain first insights into health effects from airborne exposure to these compounds, five toxigenic airborne moulds of the genera Aspergillus and Penicillium collected at composting plants and eight reference mycotoxins were tested for cytotoxicity in four established cell lines as a surrogate of tissues known or suspected to be targets of toxic effects of mycotoxins. The known mycotoxins sterigmatocystin, fumagillin, verruculogen, penitrem A, and roquefortine C were detected in extracts of the moulds. All five extracts caused serious toxic effects in the cell lines. Sterigmatocystin caused a 80-fold higher toxicity in the A-549 lung cell line compared to Hep-G2 liver cells indicating a specific susceptibility of A-549 to this agent. Since only a minor part of the toxic effects of the extracts in A-549 cells and--to a lesser extent--in the other cell lines could be explained by contents of the identified mycotoxins, the presence of additional mycotoxins or other toxic principles is assumed in the mould extracts. However, the detected mycotoxins in the mould extracts and their distinctive cytotoxicity support the hypothesis that mycotoxins may be involved in the aetiology of lung diseases due to the inhalation of organic dust. PMID:15337583

  19. Cytotoxicity and genotoxicity of biogenic silver nanoparticles

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    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.

  20. Cytotoxicity of silver dressings on diabetic fibroblasts.

    PubMed

    Zou, Shi-Bo; Yoon, Won-Young; Han, Seung-Kyu; Jeong, Seong-Ho; Cui, Zheng-Jun; Kim, Woo-Kyung

    2013-06-01

    A large number of silver-based dressings are commonly used in the management of chronic wounds that are at risk of infection, including diabetic foot ulcers. However, there are still controversies regarding the toxicity of silver dressings on wound healing. The purpose of this study was to objectively test the cytotoxicity of silver dressings on human diabetic fibroblasts. Human diabetic fibroblasts were obtained from the foot skin of four diabetic foot ulcer patients and cultured. The effect of five silver-containing dressing products (Aquacel Ag, Acticoat*Absorbent, Medifoam Ag, Biatain Ag and PolyMem Ag) and their comparable silver-free dressing products on morphology, proliferation and collagen synthesis of the cultured human diabetic fibroblasts were compared in vitro. In addition, extracts of each dressing were tested in order to examine the effect of other chemical components found in the dressings on cytotoxicity. The diabetic fibroblasts cultured with each silver-free dressing adopted the typical dendritic and fusiform shape. On the other hand, the diabetic fibroblasts did not adopt this typical morphology when treated with the different silver dressings. All silver dressings tested in the study reduced the viability of the diabetic fibroblasts and collagen synthesis by 54-70 and 48-68%, respectively, when compared to silver-free dressings. Silver dressings significantly changed the cell morphology and decreased cell proliferation and collagen synthesis of diabetic fibroblasts. Therefore, silver dressings should be used with caution when treating diabetic wounds. PMID:22533495

  1. Fibril Fragmentation Enhances Amyloid Cytotoxicity*♦

    PubMed Central

    Xue, Wei-Feng; Hellewell, Andrew L.; Gosal, Walraj S.; Homans, Steve W.; Hewitt, Eric W.; Radford, Sheena E.

    2009-01-01

    Fibrils associated with amyloid disease are molecular assemblies of key biological importance, yet how cells respond to the presence of amyloid remains unclear. Cellular responses may not only depend on the chemical composition or molecular properties of the amyloid fibrils, but their physical attributes such as length, width, or surface area may also play important roles. Here, we report a systematic investigation of the effect of fragmentation on the structural and biological properties of amyloid fibrils. In addition to the expected relationship between fragmentation and the ability to seed, we show a striking finding that fibril length correlates with the ability to disrupt membranes and to reduce cell viability. Thus, despite otherwise unchanged molecular architecture, shorter fibrillar samples show enhanced cytotoxic potential than their longer counterparts. The results highlight the importance of fibril length in amyloid disease, with fragmentation not only providing a mechanism by which fibril load can be rapidly increased but also creating fibrillar species of different dimensions that can endow new or enhanced biological properties such as amyloid cytotoxicity. PMID:19808677

  2. Cytotoxic benzophenone and triterpene from Garcinia hombroniana.

    PubMed

    Jamila, Nargis; Khairuddean, Melati; Yaacob, Nik Soriani; Kamal, Nik Nur Syazni Nik Mohamed; Osman, Hasnah; Khan, Sadiq Noor; Khan, Naeem

    2014-06-01

    Garcinia hombroniana (seashore mangosteen) in Malaysia is used to treat itching and as a protective medicine after child birth. This study was aimed to investigate the bioactive chemical constituents of the bark of G. hombroniana. Ethyl acetate and dichloromethane extracts of G. hombroniana yielded two new (1, 9) and thirteen known compounds which were characterized by the spectral techniques of NMR, UV, IR and EI/ESI-MS, and identified as; 2,3',4,5'-tetrahydroxy-6-methoxybenzophenone(1), 2,3',4,4'-tetrahydroxy-6-methoxybenzophenone (2), 2,3',4,6-tetrahydroxybenzophenone (3), 1,3,6,7-tetrahydroxyxanthone (4), 3,3',4',5,7-pentahydroxyflavone (5),3,3',5,5',7-pentahydroxyflavanone (6), 3,3',4',5,5',7-hexahydroxyflavone (7), 4',5,7-trihydroxyflavanone-7-rutinoside (8), 18(13→17)-abeo-3β-acetoxy-9α,13β-lanost-24E-en-26-oic acid (9), garcihombronane B (10), garcihombronane D (11), friedelan-3-one (12), lupeol (13), stigmasterol (14) and stigmasterol glucoside (15). In the in vitro cytotoxicity against MCF-7, DBTRG, U2OS and PC-3 cell lines, compounds 1 and 9 displayed good cytotoxic effects against DBTRG cancer cell lines. Compounds 1-8 were also found to possess significant antioxidant activities. Owing to these properties, this study can be further extended to explore more significant bioactive components of this plant. PMID:24813683

  3. Cytotoxic T-cells from T-cell receptor transgenic NOD8.3 mice destroy beta-cells via the perforin and Fas pathways.

    PubMed

    Dudek, Nadine L; Thomas, Helen E; Mariana, Lina; Sutherland, Robyn M; Allison, Janette; Estella, Eugene; Angstetra, Eveline; Trapani, Joseph A; Santamaria, Pere; Lew, Andrew M; Kay, Thomas W H

    2006-09-01

    Cytotoxic T-cells are the major mediators of beta-cell destruction in type 1 diabetes, but the molecular mechanisms are not definitively established. We have examined the contribution of perforin and Fas ligand to beta-cell destruction using islet-specific CD8(+) T-cells from T-cell receptor transgenic NOD8.3 mice. NOD8.3 T-cells killed Fas-deficient islets in vitro and in vivo. Perforin-deficient NOD8.3 T-cells were able to destroy wild-type but not Fas-deficient islets in vitro. These results imply that NOD8.3 T-cells use both pathways and that Fas is required for beta-cell killing only when perforin is missing. Consistent with this theory, transgenic NOD8.3 mice with beta-cells that do not respond to Fas ligation were not protected from diabetes. We next investigated the mechanism of protection provided by overexpression of suppressor of cytokine signaling-1 (SOCS-1) in beta-cells of NOD8.3 mice. SOCS-1 islets remained intact when grafted into NOD8.3 mice and were less efficiently killed in vitro. However, addition of exogenous peptide rendered SOCS-1 islets susceptible to 8.3 T-cell-mediated lysis. Therefore, NOD8.3 T-cells use both perforin and Fas pathways to kill beta-cells and the surprising blockade of NOD8.3 T-cell-mediated beta-cell death by SOCS-1 overexpression may be due in part to reduced target cell recognition. PMID:16936188

  4. Fc-optimized NKG2D-Fc constructs induce NK cell antibody-dependent cellular cytotoxicity against breast cancer cells independently of HER2/neu expression status.

    PubMed

    Raab, Stefanie; Steinbacher, Julia; Schmiedel, Benjamin J; Kousis, Philaretos C; Steinle, Alexander; Jung, Gundram; Grosse-Hovest, Ludger; Salih, Helmut R

    2014-10-15

    The ability of NK cells to mediate Ab-dependent cellular cytotoxicity (ADCC) largely contributes to the clinical success of antitumor Abs, including trastuzumab, which is approved for the treatment of breast cancer with HER2/neu overexpression. Notably, only ∼25% of breast cancer patients overexpress HER2/neu. Moreover, HER2/neu is expressed on healthy cells, and trastuzumab application is associated with side effects. In contrast, the ligands of the activating immunoreceptor NKG2D (NKG2DL) are selectively expressed on malignant cells. In this study, we took advantage of the tumor-associated expression of NKG2DL by using them as target Ags for NKG2D-IgG1 fusion proteins optimized by amino acid exchange S239D/I332E in their Fc part. Compared to constructs with wild-type Fc parts, fusion proteins carrying the S239D/I332E modification (NKG2D-Fc-ADCC) mediated highly enhanced degranulation, ADCC, and IFN-γ production of NK cells in response to breast cancer cells. NKG2D-Fc-ADCC substantially enhanced NK reactivity also against HER2/neu-low targets that were unaffected by trastuzumab, as both compounds mediated their immunostimulatory effects in strict dependence of target Ag expression levels. Thus, in line with the hierarchically organized potential of the various activating receptors governing NK reactivity and due to its highly increased affinity to CD16, NKG2D-Fc-ADCC potently enhances NK cell reactivity despite the inevitable reduction of activating signals upon binding to NKG2DL. Due to the tumor-restricted expression of NKG2DL, NKG2D-Fc-ADCC may constitute an attractive means for immunotherapy especially of HER2/neu-low or -negative breast cancer. PMID:25217158

  5. In vitro macrophage cytotoxicity of five calcium silicates.

    PubMed Central

    Skaug, V; Davies, R; Gylseth, B

    1984-01-01

    Five calcium silicate minerals (two naturally occurring and three synthetic compounds) with defined morphology and chemical composition were compared for their cytotoxic and lysosomal enzyme releasing effects on unstimulated mouse peritoneal macrophages in vitro. One synthetic material, a fibrous tobermorite, was cytotoxic towards the cells, and two naturally occurring wollastonites induced selective release of beta-glucuronidase from the cells. Images PMID:6318798

  6. [Study of cytotoxic and antiviral effects of some eye drops].

    PubMed

    Dediulescu, Lucreţia; Dediulescu, Daniela Florentina

    2008-01-01

    The study of the cytotoxic and antiviral effect of six commercial mixtures, eye drops type, underlined the advantages of using eye drops with Indomethacin for Herpetic Keratitis, due to the antiviral effect and also for the lack of cytotoxicity. PMID:19354165

  7. New cytotoxic steroids from the soft coral Clavularia viridis.

    PubMed

    Duh, Chang-Yih; Lo, I-Wen; Wang, Shang-Kwei; Dai, Chang-Feng

    2007-06-01

    Ten new cytotoxic steroids, stoloniferones H-Q (1-10) were isolated from the methylene chloride solubles of the soft coral Clavularia viridis. The structures of the metabolites were elucidated on the basis of spectroscopic (IR, MS, and 1D and 2D NMR) analysis and their cytotoxicity against selected cancer cells was measured in vitro. PMID:17485104

  8. Size dependent cytotoxicity of fly ash particles

    SciTech Connect

    Liu, W.K.; Tam, J.S.K.; Wong, M.H.

    1988-01-01

    Fly ash samples were collected from the electrostatic precipitator of a coal-fired power plant in Hong Kong. The particles of the respirable range (smaller than 10 {mu}m) were divided into 4 groups according to their particle size (mass median aerodynamic diameters). The surface morphology and the metal contents (Fe, Mn, Al and Zn) of fly ash particles were examined by a scanning electron microscopy and an inductively coupled plasma spectrophotometer, respectively. The particles were very heterogeneous in size and shape as well as the concentration of metals. The cytotoxicity of these four groups of fly ash particles were evaluated using an in vitro rat alveolar macrophages culture assay. The viability of alveolar macrophages was lower when incubated with smaller size particles. This relationship was also reflected by the damage of the surface morphology of the cells and the release of cytoplasmic (lactate dehydrogenase) and lysosomal (acid phosphatase and {beta}-glucuronidase) marker enzymes into the culture media.

  9. Synthesis and cytotoxic properties of tryptamine derivatives.

    PubMed

    Salikov, Rinat F; Belyy, Aleksandr Yu; Khusnutdinova, Nailya S; Vakhitova, Yulia V; Tomilov, Yury V

    2015-09-01

    The cyclopropyliminium and subsequent Grandberg rearrangements of cyclopropylketone hydrozones lead to the formation of tryptamines, which were additionally substituted at either the aromatic ring atoms or the amino group. The products were tested for their cytotoxic properties against HepG2, Jurkat and HEK293 cell lines using MTT assay. The highest activity as well as the highest selectivity was found amongst the compounds derived with one benzyl substituent at the amino group. The flow cytometry technique revealed cell-type specificity in terms of the mechanism of viability inhibition. Thus, the compounds were found to induce mainly apoptosis in HEK293 and HepG2 cells, while Jurkat cells displayed late apoptotic and necrotic responses. The apoptosis pathway is most likely to include mitochondrial damage. PMID:26174553

  10. Stability and cytotoxicity of crystallin amyloid nanofibrils.

    PubMed

    Kaur, Manmeet; Healy, Jackie; Vasudevamurthy, Madhusudan; Lassé, Moritz; Puskar, Ljiljana; Tobin, Mark J; Valery, Celine; Gerrard, Juliet A; Sasso, Luigi

    2014-11-01

    Previous work has identified crystallin proteins extracted from fish eye lenses as a cheap and readily available source for the self-assembly of amyloid nanofibrils. However, before exploring potential applications, the biophysical aspects and safety of this bionanomaterial need to be assessed so as to ensure that it can be effectively and safely used. In this study, crude crystallin amyloid fibrils are shown to be stable across a wide pH range, in a number of industrially relevant solvents, at both low and high temperatures, and in the presence of proteases. Crystallin nanofibrils were compared to well characterised insulin and whey protein fibrils using Thioflavin T assays and TEM imaging. Cell cytotoxicity assays suggest no adverse impact of both mature and fragmented crystallin fibrils on cell viability of Hec-1a endometrial cells. An IR microspectroscopy study supports long-term structural integrity of crystallin nanofibrils. PMID:25255060

  11. Fluid dynamics of cytotoxic safety cabinets.

    PubMed

    Braconnier, R; Bonthoux, F

    2010-03-01

    This study investigated the specific fluid dynamics characteristics of cytotoxic safety cabinets (CSC), particularly those used in cancer drug reconstitution operations. Measurements taken on site were used to derive characteristic data for these cabinets. An in-depth laboratory investigation of airflows inside another CSC was also conducted. Anemometric values recorded on these two installations enabled the experimental validation of computational fluid dynamics methods applied to CSC. The digital flow simulations conducted provide a better understanding of the detailed flow structure inside a CSC and made it possible to study the influence of different operating parameters on the air velocity distribution inside the cabinet front opening: recycled air temperature, product protection airflow rate, suction openings spatial distribution, air compensation mode and draughts, operator arm penetration, and operator presence in front of the cabinet. PMID:20007340

  12. Cell signaling and cytotoxicity by peroxynitrite.

    PubMed Central

    Cantoni, Orazio; Palomba, Letizia; Guidarelli, Andrea; Tommasini, Ilaria; Cerioni, Liana; Sestili, Piero

    2002-01-01

    Reactive nitrogen species are now considered to play an important role in various pathologies. Although the pathological significance of these molecules, peroxynitrite in particular, has long been attributed to their abilities to react with any component of the cells, including lipids, proteins, and DNA, a paradigm shift has recently been occurring whereby reactive nitrogen species are appreciated as signaling molecules. The question therefore arises as to whether nitrosative stress is indeed the result of a random (stochastic) process of cell damage, as it has traditionally been viewed, or rather is a consequence of the specific activation of a cascade of signaling events. The above considerations have provided the bases for the research work performed in our laboratory, and the results obtained are illustrated in the present article. In particular, our results indicate that some effects of peroxynitrite are not directly mediated by the oxidant; rather, it appears that peroxynitrite triggers a signaling pathway that finally leads to cytotoxicity. PMID:12426139

  13. Cytotoxic indole alkaloids from Tabernaemontana divaricata.

    PubMed

    Bao, Mei-Fen; Yan, Ju-Ming; Cheng, Gui-Guang; Li, Xing-Yao; Liu, Ya-Ping; Li, Yan; Cai, Xiang-Hai; Luo, Xiao-Dong

    2013-08-23

    Five new vobasinyl-ibogan-type bisindole alkaloids, tabernaricatines A-E (1-5), two new monomers, tabernaricatines F and G (6 and 7), and 24 known indole alkaloids were isolated from the aerial parts of Tabernaemontana divaricata. Alkaloids 1 and 2 are the first vobasinyl-ibogan-type alkaloids possessing a six-membered ring via an ether linkage between C-17 and C-21. All compounds except for 3 were evaluated for their cytotoxicity against five human cancer cell lines; conophylline showed significant bioactivity against HL-60, SMMC-7721, A-549, MCF-7, and SW480 cells with IC₅₀ values of 0.17, 0.35, 0.21, 1.02, and 1.49 μM, respectively. PMID:23944995

  14. Cytotoxic withanolide constituents of Physalis longifolia.

    PubMed

    Zhang, Huaping; Samadi, Abbas K; Gallagher, Robert J; Araya, Juan J; Tong, Xiaoqin; Day, Victor W; Cohen, Mark S; Kindscher, Kelly; Gollapudi, Rao; Timmermann, Barbara N

    2011-12-27

    Fourteen new withanolides, 1-14, named withalongolides A-N, respectively, were isolated from the aerial parts of Physalis longifolia together with eight known compounds (15-22). The structures of compounds 1-14 were elucidated through spectroscopic techniques and chemical methods. In addition, the structures of withanolides 1, 2, 3, and 6 were confirmed by X-ray crystallographic analysis. Using a MTS viability assay, eight withanolides (1, 2, 3, 7, 8, 15, 16, and 19) and four acetylated derivatives (1a, 1b, 2a, and 2b) showed potent cytotoxicity against human head and neck squamous cell carcinoma (JMAR and MDA-1986), melanoma (B16F10 and SKMEL-28), and normal fetal fibroblast (MRC-5) cells with IC₅₀ values in the range between 0.067 and 9.3 μM. PMID:22098611

  15. Cytotoxic Withanolide Constituents of Physalis longifolia

    PubMed Central

    Zhang, Huaping; Samadi, Abbas K.; Gallagher, Robert J.; Araya, Juan J.; Tong, Xiaoqin; Day, Victor W.; Cohen, Mark S.; Kindscher, Kelly; Gollapudi, Rao; Timmermann, Barbara N.

    2011-01-01

    Fourteen new withanolides 1-14, named withalongolides A-N, respectively, were isolated from the aerial parts of Physalis longifolia together with eight known compounds (15-22). The structures of compounds 1-14 were elucidated through spectroscopic techniques and chemical methods. In addition, the structures of withanolides 1, 2, 3, and 6 were confirmed by X-ray crystallographic analysis. Using a MTS viability assays, eight withanolides (1, 2, 3, 7, 8, 15, 16, and 19) and four acetylated derivatives (1a, 1b, 2a, and 2b) showed potent cytotoxicity against human head and neck squamous cell carcinoma (JMAR and MDA-1986), melanoma (B16F10 and SKMEL-28), and normal fetal fibroblast (MRC-5) cells with IC50 values in the range between 0.067 and 9.3 μM. PMID:22098611

  16. Cytotoxic Activities of Flavonoids from Centaurea scoparia

    PubMed Central

    Ahmed, Sayed A.; Kamel, Emadeldin M.

    2014-01-01

    Phytochemical studies on the ethanolic extract of the aerial parts of Centaurea scoparia led to the isolation of two new flavonoids, 3′,4′-dihydroxy-(3′′,4′′-dihydro-3′′-hydroxy-4′′-acetoxy)-2′′,2′′-dimethylpyrano-(5′′,6′′:7,8)-flavone-3-O-β-D-glucopyranoside (1) and 3,3′,4′-trihydroxy-(3′′,4′′-dihydro-3′′,4′′-dihydroxy)-2′′,2′′-dimethylpyrano-(5′′,6′′:7,8)-flavone (2), along with eight known flavonoids isolated for the first time from this plant, cynaroside (3), Apigetrin (4), centaureidin (5), oroxylin A (6), 5,7-dihydroxy-3′,4′,5′-trimethoxyflavone (7), atalantoflavone (8), 5-hydroxy-3′,4′,8-trimethoxy-2′′,2′′-dimethylpyrano (5′′,6′′:6,7)-flavone (9), and 3′,4′,5,8-tetramethoxy-2′′,2′′-dimethylpyrano (5′′,6′′:6,7)-flavone (10). The structures of the isolated compounds were elucidated by means of spectroscopic tools including 1D and 2D NMR, UV, IR, and mass spectroscopy. Cytotoxic activities of the isolated compounds were evaluated against human cervical carcinoma HeLa, human hepatocellular carcinoma HepG2, and human breast carcinoma MCF-7. Compound 2 was the most potent cytotoxic agent against HeLa cells with an IC50 0.079 μM. PMID:25114960

  17. Determining optimal cytotoxic activity of human Her2neu specific CD8 T cells by comparing the Cr51 release assay to the xCELLigence system.

    PubMed

    Erskine, Courtney L; Henle, Andrea M; Knutson, Keith L

    2012-01-01

    Cytotoxic CD8 T cells constitute a subgroup of T cells that are capable of inducing the death of infected or malignant host cells. These cells express a specialized receptor, called the T cell receptor (TCR), which can recognize a specific antigenic peptide bound to HLA class I molecules. Engagement of infected cells or tumor cells through their HLA class I molecule results in production of lytic molecules such as granzymes and perforin resulting in target cell death. While it is useful to determine frequencies of antigen-specific CD8 T cells using assays such as the ELIspot or flow cytometry, it is also helpful to ascertain the strength of CD8 T cell responses using cytotoxicity assays. The most recognizable assay for assessing cytotoxic function is the Chromium Release Assay (CRA), which is considered a standard assay. The CRA has several limitations, including exposure of cells to gamma radiation, lack of reproducibility, and a requirement for large numbers of cells. Over the past decade, there has been interest in adopting new strategies to overcome these limitations. Newer approaches include those that measure caspase release , BLT esterase activity and surface expression of CD107. The impedance-based assay, using the Roche xCelligence system, was examined in the present paper for its potential as an alternative to the CRA. Impedance or opposition to an electric current occurs when adherent tumor cells bind to electrode plates. Tumor cells detach following killing and electrical impedance is reduced which can be measured by the xCelligence system. The ability to adapt the impedance-based approach to assess cell-mediated killing rests on the observation that T cells do not adhere tightly to most surfaces and do not appear to have much impact on impedance thus diminishing any concern of direct interference of the T cells with the measurement. Results show that the impedance-based assay can detect changes in the levels of antigen-specific cytotoxic CD8 T cells

  18. Synthesis and cytotoxic activities of semisynthetic zearalenone analogues.

    PubMed

    Tadpetch, Kwanruthai; Kaewmee, Benyapa; Chantakaew, Kittisak; Kantee, Kawalee; Rukachaisirikul, Vatcharin; Phongpaichit, Souwalak

    2016-08-01

    Zearalenone is a β-resorcylic acid macrolide with various biological activities. Herein we report the synthesis and cytotoxic activities of 34 zearalenone analogues against human oral epidermoid carcinoma (KB) and human breast adenocarcinoma (MCF-7) cells as well as noncancerous Vero cells. Some zearalenone analogues showed moderately enhanced cytotoxic activities against the two cancer cell lines. We have discovered the potential lead compounds with diminished or no cytotoxicity to Vero cells. Preliminary structure-activity relationship studies revealed that the double bond at the 1' and 2' positions of zearalenone core was crucial for cytotoxic activities on both cell lines. In addition, for zearalenol analogues, the unprotected hydroxyl group at C-2 and an alkoxy substituent at C-4 played key roles on cytotoxic effects of both cell lines. PMID:27311894

  19. Immunohistochemical identification of cytotoxic lymphocytes using human perforin monoclonal antibody.

    PubMed Central

    Hameed, A.; Olsen, K. J.; Cheng, L.; Fox, W. M.; Hruban, R. H.; Podack, E. R.

    1992-01-01

    Perforin is a potent cytolytic pore-forming protein expressed in cytoplasmic granules of cytotoxic T lymphocytes and natural killer cells. A new monoclonal antibody raised against human perforin was used to detect both in vitro and in vivo perforin expression in cytotoxic cells. Immunohistochemical analysis of human peripheral blood mononuclear cells cultured in recombinant interleukin-2 (rIL-2) showed strong granular cytoplasmic staining of the IL-2 activated cytotoxic cells. Fresh-frozen tissue sections from patients with heart allograft rejection were also stained. Strong granular cytoplasmic staining of the mononuclear inflammatory infiltrate characteristic for perforin in cardiac allograft rejection was observed. The detection and quantitative analysis of perforin-associated cytotoxic cells by the human anti-perforin monoclonal antibody will help to evaluate the significance of these functionally distinct cytotoxic cells in human tissue. Images Figure 1 PMID:1374586

  20. Pseudorabies Virus US3 Protein Kinase Protects Infected Cells from NK Cell-Mediated Lysis via Increased Binding of the Inhibitory NK Cell Receptor CD300a

    PubMed Central

    Grauwet, K.; Vitale, M.; De Pelsmaeker, S.; Jacob, T.; Laval, K.; Moretta, L.; Parodi, M.; Parolini, S.; Cantoni, C.

    2015-01-01

    ABSTRACT Several reports have indicated that natural killer (NK) cells are of particular importance in the innate response against herpesvirus infections. As a consequence, herpesviruses have developed diverse mechanisms for evading NK cells, although few such mechanisms have been identified for the largest herpesvirus subfamily, the alphaherpesviruses. The antiviral activity of NK cells is regulated by a complex array of interactions between activating/inhibitory receptors on the NK cell surface and the corresponding ligands on the surfaces of virus-infected cells. Here we report that the US3 protein kinase of the alphaherpesvirus pseudorabies virus (PRV) displays previously uncharacterized immune evasion properties: it triggers the binding of the inhibitory NK cell receptor CD300a to the surface of the infected cell, thereby providing increased CD300a-mediated protection of infected cells against NK cell-mediated lysis. US3-mediated CD300a binding was found to depend on aminophospholipid ligands of CD300a and on group I p21-activated kinases. These data identify a novel alphaherpesvirus strategy for evading NK cells and demonstrate, for the first time, a role for CD300a in regulating NK cell activity upon contact with virus-infected target cells. IMPORTANCE Herpesviruses have developed fascinating mechanisms to evade elimination by key elements of the host immune system, contributing to their ability to cause lifelong infections with recurrent reactivation events. Natural killer (NK) cells are central in the innate antiviral response. Here we report that the US3 protein kinase of the alphaherpesvirus pseudorabies virus displays a previously uncharacterized capacity for evasion of NK cells. Expression of US3 protects infected cells from NK cell-mediated lysis via increased binding of the inhibitory NK cell receptor CD300a. We show that this US3-mediated increase in CD300a binding depends on aminophospholipids and on cellular p21-activated kinases (PAKs). The

  1. IGRP and insulin vaccination induce CD8+ T cell-mediated autoimmune diabetes in the RIP-CD80GP mouse.

    PubMed

    Fuchs, Y F; Adler, K; Lindner, A; Karasinsky, A; Wilhelm, C; Weigelt, M; Balke, H; Förtsch, K; Mortler-Hildebrandt, L F; Harlan, D M; Pechhold, K; Ziegler, A-G; Bonifacio, E

    2014-05-01

    Autoimmune diabetes is characterized by autoantigen-specific T cell-mediated destruction of pancreatic islet beta cells, and CD8(+) T cells are key players during this process. We assessed whether the bitransgenic RIP-CD80 x RIP-LCMV-GP (RIP-CD80GP) mice may be a versatile antigen-specific model of inducible CD8(+) T cell-mediated autoimmune diabetes. Antigen-encoding DNA, peptide-loaded dendritic cells and antigen plus incomplete Freund's adjuvant were used for vaccination. Of 14 pancreatic proteins tested by DNA vaccination, murine pre-proinsulin 2 (100% of mice; median time after vaccination, 60 days) and islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP) (77%, 58 days) could induce diabetes. Vaccination with DNA encoding for zinc transporter 8, Ia-2, Ia-2β, glutamic acid decarboxylase 67 (Gad67), chromogranin A, insulinoma amyloid polypeptide and homeobox protein Nkx-2.2 induced diabetes development in 25-33% of mice. Vaccination with DNA encoding for Gad65, secretogranin 5, pancreas/duodenum homeobox protein 1 (Pdx1), carboxyl ester lipase, glucagon and control hepatitis B surface antigen (HBsAg) induced diabetes in <20% of mice. Diabetes induction efficiency could be increased by DNA vaccination with a vector encoding a ubiquitin-antigen fusion construct. Diabetic mice had florid T cell islet infiltration. CD8(+) T cell targets of IGRP were identified with a peptide library-based enzyme-linked immunospot assay, and diabetes could also be induced by vaccination with major histocompatibility complex (MHC) class I-restricted IGRP peptides loaded on mature dendritic cells. Vaccination with antigen plus incomplete Freund's adjuvant, which can prevent diabetes in other models, led to rapid diabetes development in the RIP-CD80GP mouse. We conclude that RIP-CD80GP mice are a versatile model of antigen specific autoimmune diabetes and may complement existing mouse models of autoimmune diabetes for evaluating CD8(+) T cell

  2. Silica vesicles as nanocarriers and adjuvants for generating both antibody and T-cell mediated immune resposes to Bovine Viral Diarrhoea Virus E2 protein.

    PubMed

    Mody, Karishma T; Mahony, Donna; Zhang, Jun; Cavallaro, Antonino S; Zhang, Bing; Popat, Amirali; Mahony, Timothy J; Yu, Chengzhong; Mitter, Neena

    2014-12-01

    Bovine Viral Diarrhoea Virus (BVDV) is widely distributed in cattle industries and causes significant economic losses worldwide annually. A limiting factor in the development of subunit vaccines for BVDV is the need to elicit both antibody and T-cell-mediated immunity as well as addressing the toxicity of adjuvants. In this study, we have prepared novel silica vesicles (SV) as the new generation antigen carriers and adjuvants. With small particle size of 50 nm, thin wall (~6 nm), large cavity (~40 nm) and large entrance size (5.9 nm for SV-100 and 16 nm for SV-140), the SV showed high loading capacity (∼ 250 μg/mg) and controlled release of codon-optimised E2 (oE2) protein, a major immunogenic determinant of BVDV. The in vivo functionality of the system was validated in mice immunisation trials comparing oE2 plus Quil A (50 μg of oE2 plus 10 μg of Quil A, a conventional adjuvant) to the oE2/SV-140 (50 μg of oE2 adsorbed to 250 μg of SV-140) or oE2/SV-140 together with 10 μg of Quil A. Compared to the oE2 plus Quil A, which generated BVDV specific antibody responses at a titre of 10(4), the oE2/SV-140 group induced a 10 times higher antibody response. In addition, the cell-mediated response, which is essential to recognise and eliminate the invading pathogens, was also found to be higher [1954-2628 spot forming units (SFU)/million cells] in mice immunised with oE2/SV-140 in comparison to oE2 plus Quil A (512-1369 SFU/million cells). Our study has demonstrated that SV can be used as the next-generation nanocarriers and adjuvants for enhanced veterinary vaccine delivery. PMID:25239045

  3. DNA Prime/Adenovirus Boost Malaria Vaccine Encoding P. falciparum CSP and AMA1 Induces Sterile Protection Associated with Cell-Mediated Immunity

    PubMed Central

    Chuang, Ilin; Sedegah, Martha; Cicatelli, Susan; Spring, Michele; Polhemus, Mark; Tamminga, Cindy; Patterson, Noelle; Guerrero, Melanie; Bennett, Jason W.; McGrath, Shannon; Ganeshan, Harini; Belmonte, Maria; Farooq, Fouzia; Abot, Esteban; Banania, Jo Glenna; Huang, Jun; Newcomer, Rhonda; Rein, Lisa; Litilit, Dianne; Richie, Nancy O.; Wood, Chloe; Murphy, Jittawadee; Sauerwein, Robert; Hermsen, Cornelus C.; McCoy, Andrea J.; Kamau, Edwin; Cummings, James; Komisar, Jack; Sutamihardja, Awalludin; Shi, Meng; Epstein, Judith E.; Maiolatesi, Santina; Tosh, Donna; Limbach, Keith; Angov, Evelina; Bergmann-Leitner, Elke; Bruder, Joseph T.; Doolan, Denise L.; King, C. Richter; Carucci, Daniel; Dutta, Sheetij; Soisson, Lorraine; Diggs, Carter; Hollingdale, Michael R.; Ockenhouse, Christian F.; Richie, Thomas L.

    2013-01-01

    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 was

  4. Resistance of cytotoxic T lymphocytes to lysis by a clone of cytotoxic T lymphocytes.

    PubMed Central

    Kranz, D M; Eisen, H N

    1987-01-01

    To investigate how cytotoxic T lymphocytes (CTL) avoid killing themselves when they destroy target cells, we compared 20 different cell lines as target cells, including several CTL cell lines, for their susceptibility to lysis by CTL. Variations in recognition of this diverse set of target cells was circumvented by attaching to all of them a monoclonal antibody to the antigen-specific receptor of a cloned CTL cell line (clone 2C) and using the 2C cell line as the standard aggressor or effector cell. All of the nine tumor cell lines and the four noncytolytic T-helper cell lines tested as targets were highly susceptible to lysis by the aggressor CTL, but seven cytotoxic T-cell lines (six CTL and one T-helper cell line with cytotoxic activity) were largely resistant. These results, and the use of the lectin Con A as an alternative means for triggering CTL activity, point clearly to a level of resistance that could enable CTL to avoid their own destruction when they lyse target cells. The resistance of the cytolytic T cells did not appear to be accompanied by a similar resistance to complement-mediated lysis, indicating that mechanisms of CTL-mediated and complement-mediated lysis are not identical. PMID:2953028

  5. Immunoregulatory CD4+ CD45R+ suppressor/inducer T lymphocyte subsets and impaired cell-mediated immunity in patients with Down's syndrome.

    PubMed Central

    Raziuddin, S; Elawad, M E

    1990-01-01

    The monoclonal antibodies 2H4 and 4B4 allow CD4+ and CD8+ T lymphocytes to be subdivided into CD45R+ and CDW29+ functional subpopulations. The CD4+ CD45R+ lymphocytes are designated as suppressor/inducer and CD4+ CDW29+ as helper/inducer subsets. Peripheral blood lymphocytes from 19 patients with Down's syndrome and 19 age- and sex-matched normal controls were analysed for the CD45R+ and CDW29+ subsets from the CD4+ and CD8+ T lymphocytes. The percentage of CD4+ CD45R+ cells (suppressor inducer) was markedly increased and of CD4+ CDW29+ cells (helper/inducer) decreased in all patients with Down's syndrome. In contract, the percentage of CD8+ CD45R+ and CD8+ CDW29+ subsets showed no major differences between patients with Down's syndrome and normal controls. Moreover, an alteration in the CD4+ and CD45R+ and CD4+ CDW29+ T cell subsets was accompanied by a markedly reduced proliferative response to phytohaemagglutinin and concanavalin A stimulation of the CD4+ T lymphocytes. Thus, a deficiency exists in patients with Down's syndrome in the CD4+ CDW29+ helper/inducer T cell subset which may contribute to their impaired cell-mediated immunity. PMID:1967994

  6. Primary vaccination with the LiESP/QA-21 vaccine (CaniLeish) produces a cell-mediated immune response which is still present 1 year later.

    PubMed

    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. PMID:24560650

  7. Effects of inoculum size on cell-mediated and humoral immune responses of foals experimentally infected with Rhodococcus equi: a pilot study.

    PubMed

    Jacks, Stephanie; Giguère, Steeve

    2010-02-15

    The objective of this pilot study was to compare the cytokine profile as well as cell-mediated and antibody responses of foals infected with a low inoculum of virulent Rhodococcus equi resulting in subclinical pneumonia to that of foals infected with a high inoculum resulting in severe clinical pneumonia. The mean (+/-SD) ratio of post-infection to pre-infection anti-R. equi IgG(T) concentration was significantly (P=0.002) higher in foals infected with the high inoculum (195+/-145; range 62-328) compared to foals infected with the low inoculum (3.9+/-4.5; range 0.5-11). Similarly, mean (+/-SD) ratio of post-infection to pre-infection IgM concentration was significantly (P=0.002) higher in foals infected with the high inoculum (12+/-4.0; range 7.4-14) compared to foals infected with the low inoculum (2.5+/-1.5; range 1.2-4.7). Proliferative responses to R. equi antigens as well as expression of mRNA for IL-2, IL-4, IL-10, and IFN-gamma in BLN were not significantly different between the two groups. There was a tendency (P=0.073) towards a higher IFN-gamma/IL-4 ratio in the low inoculum group. This study demonstrates that the size of inoculum modulates the IgG subisotype response and possibly the cytokine profile of foals. PMID:19720402

  8. Analysis of leukocyte populations in Canadian Holsteins classified as high or low immune responders for antibody- or cell-mediated immune response.

    PubMed

    Hine, Brad C; Cartwright, Shannon L; Mallard, Bonnie A

    2012-04-01

    Selection of dairy cattle for increased milk production with little or no emphasis on health traits leads to an increased prevalence of disease. A possible genetic solution to this problem is to combine production and immune response traits in a weighted selection index. In the current study, leukocyte populations in heifers identified as having a high antibody-mediated immune response (HiAMIR) or high cell-mediated immune response (HiCMIR) phenotype were compared before and after immunization in order to identify leukocyte population profiles associated with these phenotypes. The results demonstrated that the HiCMIR-phenotype animals had a higher baseline proportion of gamma-delta T-cells in peripheral blood. Also, the observed increase in the proportion of B-cells in peripheral blood in response to immunization was greater in the HiAMIR-phenotype animals. It is expected that identifying leukocyte population profiles associated with immune response phenotypes will improve our ability to identify animals with enhanced overall immune responsiveness. PMID:23024458

  9. Humoral and cell-mediated immunity to the Plasmodium falciparum ring-infected erythrocyte surface antigen in an adult population exposed to highly endemic malaria.

    PubMed Central

    Beck, H P; Felger, I; Genton, B; Alexander, N; al-Yaman, F; Anders, R F; Alpers, M

    1995-01-01

    A parasitological and immunological survey was carried out in an area in Papua New Guinea highly endemic for malaria. Two hundred fourteen adult individuals were selected for studies to assess their immune responses against the malaria vaccine candidate ring-infected erythrocyte surface antigen (RESA). Total immunoglobulin G (IgG) antibodies directed against RESA as well as specific IgG1, IgG2, and IgG3 antibodies were determined. Humoral responses directed against RESA were frequent in all IgG subclasses. Only IgG3 responses were found to be age dependent. Total anti-RESA IgG antibodies were not correlated with protection against malaria as measured by parasite prevalence, parasite density, or health center attendance. In contrast, cytophilic antibodies (IgG1 and IgG3) were associated with reduced Plasmodium falciparum prevalence and reduced health center attendance. T-cell proliferation in general was low and very infrequent. No correlation between humoral and cellular immune responses could be found. Parasite density, parasite prevalence, and health center visits tended to be reduced in individuals with good humoral and cell-mediated immune responses. PMID:7822028

  10. An antioxidant agent prevents NO sub 2 -induced inhibition of mast cell mediator release: Evidence that the mechanism involves free radicals

    SciTech Connect

    Fujimaki, Hidekazu; Shiraishi, Fujio; Wakamori, Kazuo Jikei Univ. School of Medicine, Tokyo )

    1990-12-01

    Previously we established that in vitro NO{sub 2} exposure induced inhibition of histamine release from rat peritoneal mast cells (PMC) stimulated with secretagogues such as compound 48/80 or substance P. To further explore the effects of NO{sub 2} exposure on mast cells, we investigated whether the addition of an antioxidant agent, 2-mercaptoethanol (2-ME), can prevent NO{sub 2}-induced inhibition of mediator release from PMC. Histamine release from 5 ppm NO{sub 2}-exposed PMC stimulated with 20 {mu}M substance P was also significantly inhibited compared with that from the controls. {beta}-Hexosaminidase release from 5 ppm NO{sub 2}-exposed PMC stimulated with 20 {mu}M substance P was also significantly inhibited. However, the inhibition of both histamine and {beta}-hexosaminidase release from exposed PMC was diminished by the addition of 5 mM 2-ME during NO{sub 2} exposure. Although IgE-mediated histamine release from NO{sub 2} exposed PMC was markedly inhibited, the addition of 5 mM 2-ME during NO{sub 2} exposure induced no inhibition of histamine release. These results suggest a possible relationship between NO{sub 2}-induced inhibition of mast cell mediator release and production of free radicals by the action of NO{sub 2}.

  11. 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.

    PubMed

    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. PMID:26478541

  12. Hemagglutinin-based polyanhydride nanovaccines against H5N1 influenza elicit protective virus neutralizing titers and cell-mediated immunity

    PubMed Central

    Ross, Kathleen A; Loyd, Hyelee; Wu, Wuwei; Huntimer, Lucas; Ahmed, Shaheen; Sambol, Anthony; Broderick, Scott; Flickinger, Zachary; Rajan, Krishna; Bronich, Tatiana; Mallapragada, Surya; Wannemuehler, Michael J; Carpenter, Susan; Narasimhan, Balaji

    2015-01-01

    H5N1 avian influenza is a significant global concern with the potential to become the next pandemic threat. Recombinant subunit vaccines are an attractive alternative for pandemic vaccines compared to traditional vaccine technologies. In particular, polyanhydride nanoparticles encapsulating subunit proteins have been shown to enhance humoral and cell-mediated immunity and provide protection upon lethal challenge. In this work, a recombinant H5 hemagglutinin trimer (H53) was produced and encapsulated into polyanhydride nanoparticles. The studies performed indicated that the recombinant H53 antigen was a robust immunogen. Immunizing mice with H53 encapsulated into polyanhydride nanoparticles induced high neutralizing antibody titers and enhanced CD4+ T cell recall responses in mice. Finally, the H53-based polyanhydride nanovaccine induced protective immunity against a low-pathogenic H5N1 viral challenge. Informatics analyses indicated that mice receiving the nanovaccine formulations and subsequently challenged with virus were similar to naïve mice that were not challenged. The current studies provide a basis to further exploit the advantages of polyanhydride nanovaccines in pandemic scenarios. PMID:25565816

  13. Modulation of CD112 by the alphaherpesvirus gD protein suppresses DNAM-1–dependent NK cell-mediated lysis of infected cells

    PubMed Central

    Grauwet, Korneel; Cantoni, Claudia; Parodi, Monica; De Maria, Andrea; Devriendt, Bert; Pende, Daniela; Moretta, Lorenzo; Vitale, Massimo; Favoreel, Herman W.

    2014-01-01

    Natural killer (NK) cells are key players in the innate response to viruses, including herpesviruses. In particular, the variety of viral strategies to modulate the recognition of certain herpesviruses witnesses the importance of NK cells in the control of this group of viruses. Still, NK evasion strategies have remained largely elusive for the largest herpesvirus subfamily, the alphaherpesviruses. Here, we report that the gD glycoprotein of the alphaherpesviruses pseudorabies virus (PRV) and herpes simplex virus 2 (HSV-2) displays previously uncharacterized immune evasion properties toward NK cells. Expression of gD during infection or transfection led to degradation and consequent down-regulation of CD112, a ligand for the activating NK receptor DNAX accessory molecule 1 (DNAM-1). CD112 downregulation resulted in a reduced ability of DNAM-1 to bind to the surface of both virus-infected and gD-transfected cells. Consequently, expression of gD suppressed NK cell degranulation and NK cell-mediated lysis of PRV- or HSV-2–infected cells. These data identify an alphaherpesvirus evasion strategy from NK cells and point out that interactions between viral envelope proteins and host cell receptors can have biological consequences that stretch beyond virus entry. PMID:25352670

  14. Humoral and Cell-mediated Autoimmune Reactions to Human Acidic Ribosomal P2 Protein in Individuals Sensitized to Aspergillus fumigatus P2 Protein

    PubMed Central

    Mayer, Christina; Appenzeller, Ulrich; Seelbach, Heike; Achatz, Gernot; Oberkofler, Hannes; Breitenbach, Michael; Blaser, Kurt; Crameri, Reto

    1999-01-01

    A panel of cDNAs encoding allergenic proteins was isolated from an Aspergillus fumigatus cDNA library displayed on the surface of filamentous phage. Solid phase–immobilized serum immunoglobulin E (IgE) from A. fumigatus–allergic individuals was used to enrich phage displaying IgE-binding molecules. One of the cDNAs encoded a 11.1-kD protein that was identified as acidic ribosomal phosphoprotein type 2 (P2 protein). The allergen, formally termed rAsp f 8, shares >62% sequence identity and >84% sequence homology to corresponding eukaryotic P2 proteins, including human P2 protein. The sequences encoding human and fungal P2 protein were subcloned, expressed in Escherichia coli as His6-tagged fusion proteins, and purified by Ni2+–chelate affinity chromatography. Both recombinant P2 proteins were recognized by IgE antibodies from allergic individuals sensitized to the A. fumigatus P2 protein and elicited strong type 1–specific skin reactions in these individuals. Moreover, human and fungal P2 proteins induced proliferative responses in peripheral blood mononuclear cells of A. fumigatus– allergic subjects sensitized to the fungal P2 protein. These data provide strong evidence for in vitro and in vivo humoral and cell-mediated autoreactivity to human P2 protein in patients suffering from chronic A. fumigatus allergy. PMID:10224291

  15. Designing the method for optical in vitro monitoring of the cell-mediated scaffold technology for bone regeneration based on laser-induced fluorescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Larionov, P. M.; Maslov, N. A.; Papaeva, E. O.; Tereshchenko, V. P.; Khlestkin, V. K.; Bogachev, S. S.; Proskurina, A. S.; Titov, A. T.; Filipenko, M. L.; Pavlov, V. V.; Kudrov, G. A.; Orishich, A. M.

    2016-08-01

    One of the main unsolved problems in traumatology and orthopedics is reconstruction of critical-sized segmental bone defects. We believe that implementation of noninvasive monitoring of the bioengineering stages for cell-mediated bone scaffold by laser-induced fluorescence (LIF) can become a positive aspect in mastering this technique. An electrospun scaffold model (parameters: 10 wt. % polycaprolactone; 5% wt type A gelatin; mean fiber diameter 877.1 ± 169.1, and contact angle 45.3°) seeded with BHK IR cell culture (182 ± 38 cells/mm2) was used to show the principal possibility of differentiating between the scaffold seeded and unseeded with cells. First of all, the fluorescence spectra of the cell-seeded scaffold contain a peak at 305 nm for the excitation range of 230-290 nm, which can be used to differentiate between the samples. An increase in fluorescence intensity of the cell-seeded scaffold in the range of 400- 580 nm upon excitation at 230-340 nm is also noticeable. The wavelength of 250 nm is characterized by high signal intensity and is most suitable for differentiation between the samples.

  16. Disruption of Tumor Necrosis Factor Receptor-Associated Factor 5 Exacerbates Murine Experimental Colitis via Regulating T Helper Cell-Mediated Inflammation

    PubMed Central

    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. PMID:27110068

  17. Autochthonous primary and metastatic melanomas in Hgf-Cdk4 R24C mice evade T-cell-mediated immune surveillance.

    PubMed

    Landsberg, Jennifer; Gaffal, Evelyn; Cron, Mira; Kohlmeyer, Judith; Renn, Marcel; Tüting, Thomas

    2010-10-01

    Genetically engineered mouse models offer new opportunities to investigate the role of cell-mediated immunity in the natural progression of melanoma in an immunocompetent host. Here we report that Hgf-Cdk4(R24C) mice spontaneously develop a spectrum of primary melanomas with high penetrance during their first year of life. Malignant transformation proceeds in a stepwise manner from multiple melanocytic nevi to single nodular melanomas and disseminated metastases in most mice. Migrating melanoma cells invade the draining lymph nodes without activating the immune system. Autochthonous primary tumors are destroyed following experimental introduction of immune surveillance using an adoptive lymphocyte transfer approach. However, some tumor cells are able to survive, evade immune cell control, and recur both locally and systemically. Immune tolerance in recurring tumors may be supported by immunosuppressive Gr1(+) myeloid cells. Taken together, our results demonstrate that primary and metastatic melanomas developing spontaneously in Hgf-Cdk4(R24C) mice effectively evade cellular immune surveillance. PMID:20649939

  18. Cell mediated innate responses of cattle and swine are diverse during foot-and-mouth disease virus (FMDV) infection: a unique landscape of innate immunity.

    PubMed

    Toka, Felix N; Golde, William T

    2013-05-01

    Pathogens in general and pathogenic viruses in particular have evolved a myriad of mechanisms to escape the immune response of mammalian species. Viruses that cause acute disease tend to bear characteristics that make them very contagious, as survival does not derive from chronicity of infection, but spread of disease throughout the herd. Foot-and-mouth disease virus (FMDV) is one of the most contagious viruses known. Upon infection of susceptible species, cloven-hoofed animals, the virus proliferates rapidly and causes a vesicular disease within 2-4 days. Disease symptoms resolve by 10 days to 2 weeks and in most cases, virus can no longer be detected. Periods of fever and viremia are usually brief, 1-3 days. In vivo control of virus infection and clearance of the virus during and following acute infection is of particular interest. The interaction of this virus with cells mediating the early, innate immune response has been analyzed in a number of recent studies. In most reports, the virus has a distinct inhibitory effect on the response of cells early in infection. Here we review these new data and discuss the dynamics of the interaction of virus with different cell types mediating the immune response to infection. PMID:23727070

  19. Cell-mediated immunity to pancreatic islet cells in the non-obese diabetic (NOD) mouse: in vitro characterization and time course study.

    PubMed Central

    Timsit, J; Debray-Sachs, M; Boitard, C; Bach, J F

    1988-01-01

    The non-obese diabetic (NOD) mouse is an animal model of insulin-dependent diabetes mellitus (IDDM), in which 80% of the females become diabetic after the age of 12 weeks. Using an in vitro assay we investigated the capacity of spleen lymphocytes from NOD mice to inhibit the insulin secretion of normal islet cells after stimulation by theophylline plus arginine. Spleen cells from diabetic NOD mice inhibited the insulin release of DBA/2 islet cells. Depletion experiments using monoclonal antibodies demonstrated that inhibitory cells belonged to the Lyt2 positive T lymphocyte subset. The phenomenon was not restricted by the MHC class I K region, shared by NOD and DBA/2 mice, since lymphocytes from diabetic NOD mice also inhibited the insulin secretion of normal Wistar rat islet cells. Inhibitory T cells were detected in overtly diabetic mice but also in non-diabetic females aged 5-11 weeks indicating that they are not secondary to metabolic disturbances and might contribute to their onset. Conversely they were not found in male NOD mice although some of these mice show insulitis. The presence of these inhibitory T cells might thus represent an early and sensitive marker of anti-islet cell-mediated autoimmunity. PMID:3052943

  20. Nizatidine, a small molecular compound, enhances killed H5N1 vaccine cell-mediated responses and protects mice from lethal viral challenge.

    PubMed

    Wang, Shuang; Wu, Bing; Xue, Jia; Wang, Ming; Chen, Ruiai; Wang, Bin

    2014-01-01

    Nizatidine (NIZ), closely related to Cimetidine, is a histamine H2 receptor inverse agonist used primarily as an anti-acid drug. Recent studies showed that this class of compounds may also modulate immune responses. To evaluate adjuvant effects of NIZ on vaccine immune modulation, we formulated NIZ with a H5N1 killed viral antigen and tested in vitro and in vivo. NIZ activated DC maturation and stimulated Th1 and Th2 immune responses to H5N1 vaccine. As a result, it enhanced both antibody and T cell-mediated immune responses. We also observed that a single immunization into C57BL/6 mice blocked IL-10 upregulation and potentiated Th1/Th2 dual polarization. Importantly, the inoculation of H5N1 vaccine with NIZ significantly improved protection of animals from death after challenge and reduced virus loads in the lung tissues. Considering its water-soluble nature, compared with Cimetidine, Nizatidine may be a better choice to use as a vaccine adjuvant. PMID:24253609

  1. The cytotoxicity of kaolin towards macrophages in vitro.

    PubMed Central

    Davies, R.; Griffiths, D. M.; Johnson, N. F.; Preece, A. W.; Livingston, D. C.

    1984-01-01

    The inhalation of china clay dust by man can cause pneumoconiosis. In an attempt to identify the factors responsible the cytotoxicity in vitro of china clay dust towards mouse peritoneal macrophages was examined. Respirable dusts collected at china clay drying plants were cytotoxic towards the cells. This activity was caused by kaolinite (the major mineral in china clay) and was not due to the presence of ancillary minerals. The cytotoxicity of kaolinite was not due to particle morphology and the positively charged edges of the mineral contributed only slightly to cytotoxicity. An electron microscope study showed that macrophages phagocytosed PVPNO-coated kaolinite particles indicating that the low cytotoxicity of these particles was not due to poor phagocytosis. Residence of china clay in rat lungs appeared to reduce its cytotoxicity. It was concluded that the cytotoxicity of kaolinite was probably related to the proposed amorphous silica-rich gel coating on the particles. The relevance of the findings in vitro to the effects in vivo of china clay is discussed. Images Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:6466554

  2. Stability and cytotoxicity of crystallin amyloid nanofibrils

    NASA Astrophysics Data System (ADS)

    Kaur, Manmeet; Healy, Jackie; Vasudevamurthy, Madhusudan; Lassé, Moritz; Puskar, Ljiljana; Tobin, Mark J.; Valery, Celine; Gerrard, Juliet A.; Sasso, Luigi

    2014-10-01

    Previous work has identified crystallin proteins extracted from fish eye lenses as a cheap and readily available source for the self-assembly of amyloid nanofibrils. However, before exploring potential applications, the biophysical aspects and safety of this bionanomaterial need to be assessed so as to ensure that it can be effectively and safely used. In this study, crude crystallin amyloid fibrils are shown to be stable across a wide pH range, in a number of industrially relevant solvents, at both low and high temperatures, and in the presence of proteases. Crystallin nanofibrils were compared to well characterised insulin and whey protein fibrils using Thioflavin T assays and TEM imaging. Cell cytotoxicity assays suggest no adverse impact of both mature and fragmented crystallin fibrils on cell viability of Hec-1a endometrial cells. An IR microspectroscopy study supports long-term structural integrity of crystallin nanofibrils.Previous work has identified crystallin proteins extracted from fish eye lenses as a cheap and readily available source for the self-assembly of amyloid nanofibrils. However, before exploring potential applications, the biophysical aspects and safety of this bionanomaterial need to be assessed so as to ensure that it can be effectively and safely used. In this study, crude crystallin amyloid fibrils are shown to be stable across a wide pH range, in a number of industrially relevant solvents, at both low and high temperatures, and in the presence of proteases. Crystallin nanofibrils were compared to well characterised insulin and whey protein fibrils using Thioflavin T assays and TEM imaging. Cell cytotoxicity assays suggest no adverse impact of both mature and fragmented crystallin fibrils on cell viability of Hec-1a endometrial cells. An IR microspectroscopy study supports long-term structural integrity of crystallin nanofibrils. Electronic supplementary information (ESI) available: ThT fluorescence graphs of buffers and solvents used for

  3. Cytotoxicity of Naturally Occurring Isoquinoline Alkaloids of Different Structural Types.

    PubMed

    Chlebek, Jakub; Doskocil, Ivo; Hulcová, Daniela; Breiterová, Katerina; Šafratová, Marcela; Havelek, Radim; Habartová, Klára; Hošt'álková, Anna; Volštátová, Tereza; Cahlíková, Lucie

    2016-06-01

    Forty-six isoquinoline alkaloids, of eleven structural types isolated in our laboratory, have been evaluated for their cytotoxicity against two cancer cell lines (Caco-2 and Hep-G2 cancer cells), as well as against normal human lung fibroblast cells. Only scoulerine, aromoline, berbamine and parfumidine showed significant cytotoxic effects, but only scoulerine was active against both Caco-2 and Hep-G2 cells (IC50 values 6.44 ± 0.87 and 4.57 ± 0.42, respectively). Unfortunately, except for parfumidine, the other active alkaloids were also cytotoxic to the normal human lung fibroblast cells. PMID:27534109

  4. Predicting cytotoxicity of PAMAM dendrimers using molecular descriptors

    PubMed Central

    Jones, David E; Ghandehari, Hamidreza

    2015-01-01

    Summary The use of data mining techniques in the field of nanomedicine has been very limited. In this paper we demonstrate that data mining techniques can be used for the development of predictive models of the cytotoxicity of poly(amido amine) (PAMAM) dendrimers using their chemical and structural properties. We present predictive models developed using 103 PAMAM dendrimer cytotoxicity values that were extracted from twelve cancer nanomedicine journal articles. The results indicate that data mining and machine learning can be effectively used to predict the cytotoxicity of PAMAM dendrimers on Caco-2 cells. PMID:26665059

  5. Comparative cytotoxicity of quantum dot and gold conjugates

    NASA Astrophysics Data System (ADS)

    Nadeau, Jay; Kumar, Anil; Dumas, Eve-Marie

    2009-02-01

    Nanoparticle toxicity is of interest for the design of anti-bacterial and anti-cancer agents, and also for development of regulations for their safe handling and disposal. However, the same reactivity that makes nanoparticles show unique optical properties also makes them interact with standard cytotoxicity agents, causing false positive and/or false negative results. We discuss which cytotoxicity assays are most likely to work with nanoparticles and which are to be avoided, and present some results on comparative cytotoxicity of different types of conjugates.

  6. CYTOTOXICITY AND BIOCOMPATIBILITY OF DIRECT AND INDIRECT PULP CAPPING MATERIALS

    PubMed Central

    Modena, Karin Cristina da Silva; Casas-Apayco, Leslie Caroll; Atta, Maria Teresa; Costa, Carlos Alberto de Souza; Hebling, Josimeri; Sipert, Carla Renata; Navarro, Maria Fidela de Lima; Santos, Carlos Ferreira

    2009-01-01

    There are several studies about the cytotoxic effects of dental materials in contact with the pulp tissue, such as calcium hydroxide (CH), adhesive systems, resin composite and glass ionomer cements. The aim of this review article was to summarize and discuss the cytotoxicity and biocompatibility of materials used for protection of the dentin-pulp complex, some components of resin composites and adhesive systems when placed in direct or indirect contact with the pulp tissue. A large number of dental materials present cytotoxic effects when applied close or directly to the pulp, and the only material that seems to stimulate early pulp repair and dentin hard tissue barrier formation is CH. PMID:20027424

  7. Synthesis and Cytotoxicity of Semisynthetic Withalongolide A Analogues

    PubMed Central

    2013-01-01

    The natural product withaferin A exhibits potent antitumor activity and other diverse pharmacological activities. The recently discovered withalongolide A, a C-19 hydroxylated congener of withaferin A, was recently reported to possess cytotoxic activity against head and neck squamous cell carcinomas. Semisynthetic acetylated analogues of withalongolide A were shown to be considerably more cytotoxic than the parent compound. To further explore the structure–activity relationships, 20 new semisynthetic analogues of withalongolide A were synthesized and evaluated for cytotoxic activity against four different cancer cell lines. A number of derivatives were found to be more potent than the parent compound and withaferin A. PMID:24273633

  8. "False" cytotoxicity of ions-adsorbing hydroxyapatite - Corrected method of cytotoxicity evaluation for ceramics of high specific surface area.

    PubMed

    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. PMID:27157729

  9. Cytotoxic Sesquiterpene Lactones from Kauna lasiophthalma Griseb

    PubMed Central

    Maldonado, Eliana M.; Svensson, Daniel; Oredsson, Stina M.; Sterner, Olov

    2014-01-01

    Two new eudesmane derivatives (3 and 8) were isolated from the ethanol extract of the aerial parts of Kaunia lasiophthalma Griseb, together with 14 known eudesmane, germacrane, and guaiane sesquiterpenes, and four flavones. The structures and relative configurations of all the compounds were established by NMR spectroscopy and high-resolution mass spectrometry. The anticancer activity of sesquiterpenes 1, 3, 6–9, 11, 12, 14, and 16 was evaluated in vitro with the breast cancer cell lines HCC1937, JIMT-1, L56Br-C1, MCF-7, and SK-BR-3, and compared with the cytotoxicity in the non-cancerous breast epithelial cell line MCF-10A. All compounds were found to possess anticancer activity, and compound 1 was the most potent in all of the investigated cancer cell lines with IC50 values ranging between 2.0 and 6.2 μM. In order to demonstrate the importance of the α-methylene-γ-lactone/ester moiety present in all compounds for the effects on the cells, the methyl cysteine adduct 21 was prepared from 9 and found to be inactive or considerably less potent. PMID:24634851

  10. Nanomaterial Induced Immune Responses and Cytotoxicity.

    PubMed

    Ali, Ashraf; Suhail, Mohd; Mathew, Shilu; Shah, Muhammad Ali; Harakeh, Steve M; Ahmad, Sultan; Kazmi, Zulqarnain; Alhamdan, Mohammed Abdul Rahman; Chaudhary, Adeel; Damanhouri, Ghazi Abdullah; Qadri, Ishtiaq

    2016-01-01

    Nanomaterials are utilized in a wide array of end user products such as pharmaceuticals, electronics, clothes and cosmetic products. Due to its size (< 100 nm), nanoparticles have the propensity to enter through the airway and skin, making its path perilous with the potential to cause damages of varying severity. Once within the body, these particles have unconstrained access to different tissues and organs including the brain, liver, and kidney. As a result, nanomaterials may cause the perturbation of the immune system eliciting an inflammatory response and cytotoxicity. This potential role is dependent on many factors such as the characteristics of the nanomaterials, presence or absence of diseases, and genetic predisposition. Cobalt and nickel nanoparticles, for example, were shown to have inflammogenic properties, while silver nanoparticles were shown to reduce allergic inflammation. Just as asbestos fibers, carbon nanotubes were shown to cause lungs damage. Some nanomaterials were shown, based on animal studies, to result in cell damage, leading to the formation of pre-cancerous lesions. This review highlights the impact of nanomaterials on immune system and its effect on human health with toxicity consideration. It recommends the development of suitable animal models to study the toxicity and bio-clearance of nanomaterials and propose safety guidelines. PMID:27398432

  11. The Cytotoxicity of Layered Black Phosphorus.

    PubMed

    Latiff, Naziah Mohamad; Teo, Wei Zhe; Sofer, Zdenek; Fisher, Adrian C; Pumera, Martin

    2015-09-28

    Black phosphorus (BP), the latest addition to the family of 2D layered materials, has attracted much interest owing to potential optoelectronics, nanoelectronics, and biomedicine applications. Little is known about its toxicity, such as whether it could be as toxic as white phosphorus. In response to the possibility of BP employment into commercial products and biomedical devices, its cytotoxicity to human lung carcinoma epithelial cells (A549) was investigated. Following a 24 h exposure of the cells with different BP concentrations, cell viability assessments were conducted using water-soluble tetrazolium salt (WST-8) and methylthiazolyldiphenyltetrazolium bromide (MTT) assays. The toxicological effects were found to be dose-dependent, with BP reducing cell viabilities to 48% (WST-8) and 34% (MTT) at 50 μg mL(-1) exposure. This toxicity was observed to be generally intermediate between that of graphene oxides and exfoliated transition-metal dichalcogenides (MoS2, WS2, WSe2). The relatively low toxicity paves the way to utilization of black phosphorus. PMID:26291565

  12. Cytotoxicity Test and Mass Spectrometry of IPMC

    NASA Astrophysics Data System (ADS)

    Takashima, Kazuto; Kamamichi, Norihiro; Yagi, Tohru; Asaka, Kinji; Mukai, Toshiharu

    Ionic polymer-metal composite (IPMC) is a promising material in biomedical actuators and sensors because IPMC is soft and flexible, leading to the safety of the device itself. The purpose of this study is to investigate the biocompatibility of IPMC by in vitro experiments, in order to evaluate the applicability in biomedical fields. In addition to an IPMC specimen prepared by the conventional “impregnation-reduction method” using cationic gold complexes and reducing agents, two specimens were prepared by processes in addition to that used for the conventional IPMC specimen. One specimen was reduced in Na2SO3 solution and another specimen was cleaned in H2O2 solution. Colony-forming test using Chinese hamster V79 cells shows high cytotoxicity of all IPMC specimens. Examination of direct inlet mass spectrometry (DI-MS) revealed that the peak intensity of gold complex (particularly, m/z=180) was different from that of Nafion film. Monitoring the peak at m/z=180 showed a remnant with the structure of phenanthroline in IPMC specimens which were not cleaned in H2O2 solution.

  13. Oleandrin: A cardiac glycosides with potent cytotoxicity

    PubMed Central

    Kumar, Arvind; De, Tanmoy; Mishra, Amrita; Mishra, Arun K.

    2013-01-01

    Cardiac glycosides are used in the treatment of congestive heart failure and arrhythmia. Current trend shows use of some cardiac glycosides in the treatment of proliferative diseases, which includes cancer. Nerium oleander L. is an important Chinese folk medicine having well proven cardio protective and cytotoxic effect. Oleandrin (a toxic cardiac glycoside of N. oleander L.) inhibits the activity of nuclear factor kappa-light-chain-enhancer of activated B chain (NF-κB) in various cultured cell lines (U937, CaOV3, human epithelial cells and T cells) as well as it induces programmed cell death in PC3 cell line culture. The mechanism of action includes improved cellular export of fibroblast growth factor-2, induction of apoptosis through Fas gene expression in tumor cells, formation of superoxide radicals that cause tumor cell injury through mitochondrial disruption, inhibition of interleukin-8 that mediates tumorigenesis and induction of tumor cell autophagy. The present review focuses the applicability of oleandrin in cancer treatment and concerned future perspective in the area. PMID:24347921

  14. Cytotoxic effects of tebufenozide in vitro bioassays.

    PubMed

    Yu, Xiaoqin; Zhang, Yang; Yang, Mingjun; Guo, Junfu; Xu, Wenping; Gao, Jufang; Li, Yaxiao; Tao, Liming

    2016-07-01

    Tebufenozide is considered an environmentally friendly pesticide due to its specificity on target insects, but the effects on human are well studied. Studies on the toxicity of tebufenozide at molecular and cellular level is poorly understood. The present study reveals non-selective cytotoxic effects of tebufenozide, and the apoptotic mechanism induced by tebufenozide on HeLa and Tn5B1-4 cells. We demonstrate that the viability of HeLa and Tn5B1-4 cells is inhibited by tebufenozide in a time- and concentration-dependent manner. Intracellular biochemical assays showed that tebufenozide-induced apoptosis of two cell lines concurrent with a decrease in the mitochondrial membrane potential and an increase reactive oxygen species generation, the release of cytochrome-c into the cytosol and a marked activation of caspase-3. These results indicate that a mitochondrial-dependent intrinsic pathway contributes to tebufenozide induced apoptosis in HeLa and Tn5B1-4 cells and suggests potential threats to ecosystems and human health. PMID:27043174

  15. Biosynthetically Distinct Cytotoxic Polyketides from Setophoma terrestris

    PubMed Central

    El-Elimat, Tamam; Figueroa, Mario; Raja, Huzefa A.; Graf, Tyler N.; Swanson, Steven M.; Falkinham, Joseph O.; Wani, Mansukh C.; Pearce, Cedric J.

    2014-01-01

    Sixteen polyketides belonging to diverse structural classes, including monomeric/dimeric tetrahydroxanthones and resorcylic acid lactones, were isolated from an organic extract of a fungal culture Setophoma terrestris (MSX45109) using bioactivity-directed fractionation as part of a search for anticancer leads from filamentous fungi. Of these, six were new: penicillixanthone B (5), blennolide H (6), 11-deoxy blennolide D (7), blennolide I (9), blennolide J (10), and pyrenomycin (16). The known compounds were: secalonic acid A (1), secalonic acid E (2), secalonic acid G (3), penicillixanthone A (4), paecilin B (8), aigialomycin A (11), hypothemycin (12), dihydrohypothemycin (13), pyrenochaetic acid C (14), and nidulalin B (15). The structures were elucidated using a set of spectroscopic and spectrometric techniques; the absolute configurations of compounds 1–10 were determined using ECD spectroscopy combined with time-dependent density functional theory (TDDFT) calculations, while a modified Mosher’s ester method was used for compound 16. The cytotoxic activities of compounds (1–15) were evaluated using the MDA-MB-435 (melanoma) and SW-620 (colon) cancer cell lines. Compounds 1, 4, and 12 were the most potent with IC50 values ranging from 0.16 to 2.14 μM. When tested against a panel of bacteria and fungi, compounds 3 and 5 showed promising activity against the Gram-positive bacterium Micrococcus luteus with MIC values of 5 and 15 μg/mL, respectively. PMID:25574154

  16. Cytotoxic Sesquiterpene Lactones from Kauna lasiophthalma Griseb.

    PubMed

    Maldonado, Eliana M; Svensson, Daniel; Oredsson, Stina M; Sterner, Olov

    2014-03-01

    Two new eudesmane derivatives (3 and 8) were isolated from the ethanol extract of the aerial parts of Kaunia lasiophthalma Griseb, together with 14 known eudesmane, germacrane, and guaiane sesquiterpenes, and four flavones. The structures and relative configurations of all the compounds were established by NMR spectroscopy and high-resolution mass spectrometry. The anticancer activity of sesquiterpenes 1, 3, 6-9, 11, 12, 14, and 16 was evaluated in vitro with the breast cancer cell lines HCC1937, JIMT-1, L56Br-C1, MCF-7, and SK-BR-3, and compared with the cytotoxicity in the non-cancerous breast epithelial cell line MCF-10A. All compounds were found to possess anticancer activity, and compound 1 was the most potent in all of the investigated cancer cell lines with IC50 values ranging between 2.0 and 6.2 μM. In order to demonstrate the importance of the α-methylene-γ-lactone/ester moiety present in all compounds for the effects on the cells, the methyl cysteine adduct 21 was prepared from 9 and found to be inactive or considerably less potent. PMID:24634851

  17. Cytotoxicity effects of amiodarone on cultured cells.

    PubMed

    Golli-Bennour, Emna El; Bouslimi, Amel; Zouaoui, Olfa; Nouira, Safa; Achour, Abdellatif; Bacha, Hassen

    2012-07-01

    Amiodarone is a potent anti-arrhythmic drug used for the treatment of cardiac arrhythmias. Although, the effects of amiodarone are well characterized on post-ischemic heart and cardiomyocytes, its toxicity on extra-cardiac tissues is still poorly understood. To this aim, we have monitored the cytotoxicity effects of this drug on three cultured cell lines including hepatocytes (HepG2), epithelial cells (EAhy 926) and renal cells (Vero). We have investigated the effects of amiodarone on (i) cell viabilities, (ii) heat shock protein expressions (Hsp 70) as a parameter of protective and adaptive response and (iii) oxidative damage.Our results clearly showed that amiodarone inhibits cell proliferation, induces an over-expression of Hsp 70 and generates significant amount of reactive oxygen species as measured by lipid peroxidation occurrence. However, toxicity of amiodarone was significantly higher in renal and epithelial cells than in hepatocytes. Vitamin E supplement restores the major part of cell mortalities induced by amiodarone showing that oxidative damage is the predominant toxic effect of the drug.Except its toxicity for the cardiac system, our findings demonstrated that amiodarone can target other tissues. Therefore, kidneys present a high sensibility to this drug which may limit its use with subjects suffering from renal disorders. PMID:21093234

  18. Cytotoxic macrocyclic diterpenoid esters from Euphorbia cornigera.

    PubMed

    Baloch, Imam Bakhsh; Baloch, Musa Kaleem; Saqib, Qazi Najam

    2006-07-01

    Root extract of Euphorbia cornigera Boiss. (Euphorbiaceae) was separated into seven (compound 1-7) isolates through multiple Craig's distributions and preparative HPLC. The structures and relative configuration of theses compounds were established via spectral analyses as 7,8,12- O-triacetyl-3- O-(2-methylbutanoyl)-ingol (1), 3,8,12- O-triacetyl-7- O-(2-methylbutanoyl = -ingol (2), 3,7,12- O-triacetyl-8- O-(2-methylbutanoyl)-ingol (3), 3,7,8- O-triacetyl-12- O-(2-methylbutanoyl)-ingol (4), 7,12- O-diacetyl-3- O-(2-methylbutanoyl)-8- O-methylingol (5), 3,12- O-diacetyl-7- O-(2-methylbutanoyl)-8- O-methylingol (6) and 3,7- O-diacetyl-12- O-(2-methylbutanoyl)-8- O-methylingol (7). All these compounds, except for 2, are novel metabolites and have not been reported earlier. It has further been demonstrated that all the compounds (1 - 7) are cytotoxic. PMID:16881017

  19. Cytotoxicity of pilocarpine to human corneal stromal cells and its underlying cytotoxic mechanisms

    PubMed Central

    Yuan, Xiao-Long; Wen, Qian; Zhang, Meng-Yu; Fan, Ting-Jun

    2016-01-01

    AIM To examine the cytotoxic effect of pilocarpine, an anti-glaucoma drug, on human corneal stromal (HCS) cells and its underlying cytotoxic mechanisms using an in vitro model of non-transfected HCS cells. METHODS After HCS cells were treated with pilocarpine at a concentration from 0.15625 g/L to 20.0 g/L, their morphology and viability were detected by light microscopy and MTT assay. The membrane permeability, DNA fragmentation and ultrastructure were examined by acridine orange (AO)/ethidium bromide (EB) double-staining. DNA electrophoresis and transmission electron microscopy (TEM), cell cycle, phosphatidylserine (PS) orientation and mitochondrial transmembrane potential (MTP) were assayed by flow cytometry (FCM). And the activation of caspases was checked by ELISA. RESULTS Morphology observations and viability assay showed that pilocarpine at concentrations above 0.625 g/L induced dose- and time-dependent morphological abnormality and viability decline of HCS cells. AO/EB double-staining, DNA electrophoresis and TEM noted that pilocarpine at concentrations above 0.625 g/L induced dose- and/or time-dependent membrane permeability elevation, DNA fragmentation, and apoptotic body formation of the cells. Moreover, FCM and ELISA assays revealed that 2.5 g/L pilocarpine also induced S phase arrest, PS externalization, MTP disruption, and caspase-8, -9 and -3 activation of the cells. CONCLUSION Pilocarpine at concentrations above 0.625 g/L (1/32 of its clinical therapeutic dosage) has a dose- and time-dependent cytotoxicity to HCS cells by inducing apoptosis in these cells, which is most probably regulated by a death receptor-mediated mitochondrion-dependent signaling pathway. PMID:27162720

  20. Cytotoxic and immunogenic mechanisms of recombinant oncolytic poliovirus.

    PubMed

    Brown, Michael C; Gromeier, Matthias

    2015-08-01

    An oncolytic virus (OV) based on poliovirus (PV), the highly attenuated polio/rhinovirus recombinant PVSRIPO, may deliver targeted inflammatory cancer cell killing; a principle that is showing promise in clinical trials for recurrent glioblastoma (GBM). The two decisive factors in PVSRIPO anti-tumor efficacy are selective cytotoxicity and its in situ immunogenic imprint. While our work is focused on what constitutes PVSRIPO cancer cytotoxicity, we are also studying how this engenders host immune responses that are vital to tumor regression. We hypothesize that PVSRIPO cytotoxicity and immunogenicity are inextricably linked in essential, complimentary roles that define the anti-neoplastic response. Herein we delineate mechanisms we unraveled to decipher the basis for PVSRIPO cytotoxicity and its immunotherapeutic potential. PMID:26083317

  1. Cytotoxicity and antiviral activity of the compounds from Euphorbia kansui.

    PubMed

    Zheng, W F; Cui, Z; Zhu, Q

    1998-12-01

    Eleven compounds including four triterpenes, one sterol, and six diterpenes from E kansui had been assayed for their cytotoxicity and activiral activity. The relations between structures and bioactivities have also been noted. PMID:9933994

  2. Cytotoxic sesquiterpenes from the endophytic fungus Pseudolagarobasidium acaciicola.

    PubMed

    Wibowo, Mario; Prachyawarakorn, Vilailak; Aree, Thammarat; Mahidol, Chulabhorn; Ruchirawat, Somsak; Kittakoop, Prasat

    2016-02-01

    Twenty previously unknown compounds and two known metabolites, merulin A and merulin D, were isolated from the endophytic fungus Pseudolagarobasidium acaciicola, which was isolated from a mangrove tree, Bruguiera gymnorrhiza. Structures of the 20 compounds were elucidated by analysis of spectroscopic data. The absolute configuration of seven of these compounds was addressed by a single crystal X-ray analysis using CuKα radiation and an estimate of the Flack parameter. Three compounds also possessed a tricyclic ring system. Terpene endoperoxides isolated exhibited cytotoxic activity, while those without an endoperoxide moiety did not show activity. The endoperoxide moiety of sesquiterpenes has significant impact on cytotoxic activity, and thus is an important functionality for cytotoxicity. One terpene endoperoxide displayed potent cytotoxic activity (IC50 0.28μM), and selectively exhibited activity against the HL-60 cell line. PMID:26701647

  3. Cytotoxic diterpenoids from Jatropha curcas cv. nigroviensrugosus CY Yang Roots.

    PubMed

    Liu, JieQing; Yang, YuanFeng; Xia, JianJun; Li, XuYang; Li, ZhongRong; Zhou, Lin; Qiu, MingHua

    2015-09-01

    An investigation of phytochemicals from the roots of Jatropha curcas cv. nigroviensrugosus resulted in the isolation of twenty diterpenoids, including lathyranlactone, an unusual diterpenoid lactone possessing a 5/13/3 tricyclic skeleton, jatrocurcasenones A-E and jatrophodiones B-E, as well as 10 known analogues. All isolates were evaluated for cytotoxicity against the HL-60, SMMC-772, A-549, MCF-7 and SW480 human tumor cell lines using the MTS viability assay. Four of the known analogues showed cytotoxic activity in these cell lines, with IC50 values ranging from 2.0 to 23.0 μM. Moreover, the assessment of their cytotoxic structure-activity relationships showed the epoxy ring between C-5 and C-6 and the hydroxyl group at C-2 were the key functionalities for cytotoxicity. PMID:26209936

  4. Novel cytotoxic cembranoids from the soft coral Sinularia flexibilis.

    PubMed

    Duh, C Y; Wang, S K; Tseng, H K; Sheu, J H; Chiang, M Y

    1998-06-26

    Three new cytotoxic cembranoid diterpenes, sinuflexolide (1), dihydrosinuflexolide (2), and sinuflexibilin (3), have been isolated from the soft coral Sinularia flexibilis. The structures of compounds 1-3 were determined by spectral and X-ray crystallographic analysis. PMID:9644083

  5. IN VITRO CYTOTOXICITY OF BTEX METABOLITES IN HELA CELL LINES

    EPA Science Inventory

    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...

  6. Photoinduced cytotoxicity of a photochromic diarylethene via caspase cascade activation.

    PubMed

    Okuda, Jun-ya; Tanaka, Yukimi; Kodama, Ryuhei; Sumaru, Kimio; Morishita, Kana; Kanamori, Toshiyuki; Yamazoe, Seiji; Hyodo, Kengo; Yamazaki, Shohei; Miyatake, Tomohiro; Yokojima, Satoshi; Nakamura, Sinichiro; Uchida, Kingo

    2015-07-11

    The photo-generated closed-ring isomer of bis(5-methyl-2-phenylthiazoyl)perfluorocyclopentene shows cytotoxicity to Madin-Darby canine kidney (MDCK) cells through a caspase cascade and induces apoptosis of cells. PMID:26063471

  7. A Role for Orexin in Cytotoxic Chemotherapy-Induced Fatigue

    PubMed Central

    Weymann, K. B.; Wood, L. J.; Zhu, X.; Marks, D. L.

    2014-01-01

    Fatigue is the most common symptom related to cytotoxic chemotherapeutic treatment of cancer. Peripheral inflammation associated with cytotoxic chemotherapy is likely a causal factor of fatigue. The neural mechanisms by which cytotoxic chemotherapy associated inflammation induces fatigue behavior are not known. This lack of knowledge hinders development of interventions to reduce or prevent this disabling symptom. Infection induced fatigue/lethargy in rodents is mediated by suppression of hypothalamic orexin activity. Orexin is critical for maintaining wakefulness and motivated behavior. Though there are differences between infection and cytotoxic chemotherapy in some symptoms, both induce peripheral inflammation and fatigue. Based on these similarities we hypothesized that cytotoxic chemotherapy induces fatigue by disrupting orexin neuron activity. We found that a single dose of a cytotoxic chemotherapy cocktail (cyclophosphamide, adriamycin, 5-fluorouracil—CAF) induced fatigue/lethargy in mice and rats as evidenced by a significant decline in voluntary locomotor activity measured by telemetry. CAF induced inflammatory gene expression—IL-1R1 (p<0.001), IL-6 (p<0.01), TNFα (p<0.01), and MCP-1 (p<0.05) —in the rodent hypothalamus 6 to 24 hours after treatment during maximum fatigue/lethargy. CAF decreased orexin neuron activity as reflected by decreased nuclear cFos localization in orexin neurons 24 hours after treatment (p<0.05) and by decreased orexin-A in cerebrospinal fluid 16 hours after treatment (p<0.001). Most importantly, we found that central administration of1 μg orexin-A restored activity in CAF-treated rats (p<0.05). These results demonstrate that cytotoxic chemotherapy induces hypothalamic inflammation and that suppression of hypothalamic orexin neuron activity has a causal role in cytotoxic chemotherapy-induced fatigue in rodents. PMID:24216337

  8. Cytotoxicity of Doxycycline Effluent Generated by the Fenton Process

    PubMed Central

    Borghi, Alexandre Augusto; Stephano, Marco Antônio; Monteiro de Souza, Paula; Alves Palma, Mauri Sérgio

    2014-01-01

    This study aims at determining the Minimum Inhibitory Concentration with Escherichia coli ATCC 25922 and cytotoxicity to L929 cells (ATCC CCL-1) of the waste generated by doxycycline degradation by the Fenton process. This process has shown promise in this treatment thanks mainly to the fact that the waste did not show any relevant inhibitory effect on the test organism and no cytotoxicity to L-929 cells, thus demonstrating that the antibiotic properties were inactivated. PMID:25379532

  9. Cytotoxicity of doxycycline effluent generated by the Fenton process.

    PubMed

    Borghi, Alexandre Augusto; Oliveira-Nascimento, Laura; Stephano, Marco Antônio; de Souza, Paula Monteiro; Converti, Attilio; Palma, Mauri Sérgio Alves

    2014-01-01

    This study aims at determining the Minimum Inhibitory Concentration with Escherichia coli ATCC 25922 and cytotoxicity to L929 cells (ATCC CCL-1) of the waste generated by doxycycline degradation by the Fenton process. This process has shown promise in this treatment thanks mainly to the fact that the waste did not show any relevant inhibitory effect on the test organism and no cytotoxicity to L-929 cells, thus demonstrating that the antibiotic properties were inactivated. PMID:25379532

  10. [Two recombinant adenovirus vaccine candidates containing neuraminidase Gene of H5N1 influenza virus (A/Anhui/1/2005) elicited effective cell-mediated immunity in mice].

    PubMed

    Ma, Jing; Zhang, Xiao-Guang; Chen, Hong; Li, Kui-Biao; Zhang, Xiao-Mei; Zhang, Ke; Yang, Liang; Xu, Hong; Shu, Yue-Long; Tan, Wen-Jie; Zeng, Yi

    2009-09-01

    The aim of this study is to develop the recombinant adenovirus vaccine (rAdV) candidates containing neuraminidase (NA) gene of H5N1 influenza virus and test in BALB/c mice the effect of cell-mediated immunity. In this study, two kind of NA gene (WtNA gene, the wild type; Mod. NA gene, the codon-modified type) derived from H5N1 influenza virus (A/Anhui/1/2005) were cloned and inserted respectively into plasmid of adenovirus vector, then the rAdV vaccines candidates (rAdV-WtNA and rAdV-Mod. NA) were developed and purified, followed by immunization intramuscularly (10(9) TCID50 per dose, double injection at 0 and 4th week) in BALB/c mice, the effect of cell-mediated immunity were analysed at 5th week. Results indicated that: (i) NA protein expression was detected in two rAdV vaccines candidates by Western blotting; (ii) the rAdV-Mod. NA vaccine could elicit more robust NA specific cell-mediated immunity in mice than that of rAdV-WtNA vaccine (P = 0. 016) by IFN-gamma ELIspot assay. These findings suggested rAdV-Mod. NA vaccine was a potential vaccine candidate against H5N1 influenza and worthy of further investigation. PMID:19954107

  11. Targeting of XIAP combined with systemic mesenchymal stem cell-mediated delivery of sTRAIL ligand inhibits metastatic growth of pancreatic carcinoma cells.

    PubMed

    Mohr, Andrea; Albarenque, Stella Maris; Deedigan, Laura; Yu, Rui; Reidy, Mairead; Fulda, Simone; Zwacka, Ralf Michael

    2010-11-01

    Disseminating tumors are one of the gravest medical problems. Here, we combine the tumor-specific apoptosis-inducing activity of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) with the ability of mesenchymal stem cells (MSCs) to infiltrate both tumor and lymphatic tissues to target primary tumors as well as disseminated cancer cells in a human pancreatic cancer mouse model. Furthermore, we targeted X-linked inhibitor of apoptosis protein (XIAP) by RNA interference (RNAi) inside the cancer cells to make use of the apoptosis sensitization as well the antimetastatic effect that is afforded by XIAP silencing. We generated MSCs, termed MSC.sTRAIL, that express and secrete a trimeric form of soluble TRAIL (sTRAIL). MSC.sTRAIL triggered limited apoptosis in human pancreatic carcinoma cells that were resistant to soluble recombinant TRAIL, which is most likely due to the enhanced effect of the direct, cell-mediated delivery of trimeric TRAIL. MSC.sTRAIL-mediated cell death was markedly increased by concomitant knockdown of XIAP by RNAi in the cancer cells. These findings were confirmed in xenograft models, in which tumors from the parental pancreatic carcinoma cells showed only growth retardation on treatment with MSC.sTRAIL, whereas tumors with silenced XIAP that were treated with MSC.sTRAIL went into remission. Moreover, animals with XIAP-negative xenografts treated with MSC.sTRAIL were almost free of lung metastasis, whereas animals treated with control MSCs showed substantial metastatic growth in the lungs. In summary, this is the first demonstration that a combined approach using systemic MSC-mediated delivery of sTRAIL together with XIAP inhibition suppresses metastatic growth of pancreatic carcinoma. PMID:20882532

  12. Alarmin IL-33 acts as an immunoadjuvant for enhancing antigen-specific cell-mediated immunity resulting in potent anti-tumor immunity

    PubMed Central

    Villarreal, Daniel O.; Wise, Megan C.; Walters, Jewell N.; Reuschel, Emma; Choi, Min Joung; Obeng-Adjei, Nyamekye; Yan, Jian; Morrow, Matthew P.; Weiner, David B.

    2014-01-01

    Interleukin 33 (IL-33) has emerged as a cytokine that can exhibit pleiotropic properties. Here we examine IL-33 for its immunoadjuvant effects in an HPV-associated cancer immune therapy model in which cell-mediated immunity is critical for protection. It is known that two biologically active forms of IL-33 exist: full-length IL-33 and mature IL-33. The potential ability of both isoforms to act as vaccine adjuvants to influence the CD4 Th1 and CD8 T cell immune responses has not been well defined. We show that both isoforms of IL-33 are capable of enhancing potent antigen (Ag)-specific effector and memory T cell immunity in vivo in a DNA vaccine setting. We also show that while both forms of IL-33 drove robust IFN-γ responses, neither form drove high secretion of IL-4 or any elevation of IgE levels. Moreover, both isoforms augmented vaccine-induced Ag-specific polyfunctional CD4+ and CD8+ T cell responses, with a large proportion of CD8+ T cells undergoing cytolytic plurifunctional degranulation. Therapeutic studies indicated that established TC-1-bearing mice undergo rapid and complete regression after therapeutic vaccination with both IL-33 adjuvant isoforms used in conjunction with an HPV DNA vaccine. Furthermore, using the P14 transgenic mouse model, we show that IL-33 can significantly expand the magnitude of Ag-specific CD8+ T cell responses and elicit bonafide effector-memory CD8+ T cells. Overall, the data suggests the potential use of these two IL-33 isoforms as immunoadjuvant candidates in future vaccination against other pathogens and in the context of anti-tumor immune-based therapy. PMID:24448242

  13. Hepatitis C Virus-Specific Cell-Mediated Immune Responses in Children Born to Mothers Infected with Hepatitis C Virus

    PubMed Central

    El-Kamary, Samer S.; Hashem, Mohamed; Saleh, Doaa A.; Abdelwahab, Sayed F.; Sobhy, Maha; Shebl, Fatma M.; Shardell, Michelle D.; Strickland, G. Thomas; Shata, Mohamed Tarek

    2013-01-01

    Objective To investigate the association between hepatitis C virus (HCV)-specific cell-mediated immunity (CMI) responses and viral clearance in children born to mothers infected with HCV. Study design A cross-sectional study of children from a mother-infant cohort in Egypt were enrolled to detect CMI responses to recombinant core and nonstructural HCV antigens (nonstructural segments NS3, NS4a/b, and NS5 of the HCV genome) using an interferon-gamma enzyme-linked immunospot assay. Children born to mothers with chronic HCV were enrolled into 3 groups: transiently viremic (n = 5), aviremic (n = 36), and positive control (n = 6), which consisted of 1 child with chronic HCV from this cohort and another 5 children with chronic HCV from a companion study. Children without HCV born to mothers without HCV (n = 27) served as a negative control group. Wilcoxon rank sum test was used to compare the magnitude of CMI responses between groups. Results None of the 6 control children who were positive for HCV responded to any HCV antigen, and 4 (80%) of 5 children with transient viremia responded to at least one HCV antigen, compared with 5 (14%) of 36 and 3 (11%) of 27 children in the aviremic and negative control groups, respectively. Children with transient viremia elicited stronger responses than did negative controls (P = .005), positive controls (P = .011), or children without HCV viremia (P = .012), particularly to nonstructural antigens. Conclusions HCV-specific CMI responses were significantly higher in magnitude and frequency among transiently infected children compared with those persistently infected. This suggests CMI responses may be associated with past viral clearance and can identify children at high risk of infection, who can be targeted for health education, screening, and follow-up. PMID:22883419

  14. An investigation of the effect of anti-inflammatory and anti-rheumatoid drugs in cell-mediated immune arthritis in guinea-pigs by microfocal radiography.

    PubMed Central

    Cashin, C. H.; Doherty, N. S.; Jeffries, B. L.; Buckland-Wright, J. C.

    1980-01-01

    Guinea-pigs were sensitized by intra-articular injection of M. tuberculosis (2.0 mg) into one knee joint and arthritis induced in the opposite knee 21 days later by intra-articular injection of antigen (0.2 mg). The time course off the arthritic changes was followed for 25 days by assessment of knee swelling and hind-limb flexion. Twenty-eight days after challenge the experiment was terminated and radiographic changes evaluated by means of a microfocal X-ray unit. The effect of treatment with the anti-rheumatic drugs, D-penicillamine (100 mg/kg by mouth), dexamethasone (0.1 mg/kg i.p.), aspirin (100 mg/kg by mouth), chloroquine phosphate (30 mg/kg by mouth) and sodium aurothiomalate (2 mg/kg i.m.) given daily from 10 days after sensitization until 28 days after challenge was assessed. Changes in joint swelling and hind-limb flexion were maximal 1-3 days after challenge. None of the drug treatments influenced these parameters. Microfocal radiography showed marked changes in arthritis animals of all X-ray parameters measured. It was possible readily to identify joint erosion, trabecular loss and associated osteoporosis, the latter occurring proximal to and relatively remote from the affected joint. None of the treatments prevented the radiographic changes but exacerbation of trabecular number in the area of the epiphysis was seen with aspirin and D-penicillamine and of trabecular density further up the shaft of the femur was seen with D-penicillamine. The changes with D-penicillamine may reflect the potentiation of cell-mediated hypersensitivity with this drug reported by other workers. It was concluded that the model is not suitable for the detection of clinically active anti-rheumatic drugs but that microfocal radiography provides a sensitive index for the assessment of joint damage in small animals. Images Fig. 1 Fig. 2 PMID:6775665

  15. Gene Expression Profiles Underlying Selective T-Cell-Mediated Immunity Activity of a Chinese Medicine Granule on Mice Infected with Influenza Virus H1N1

    PubMed Central

    Lu, Na-na; Liu, Qi; Gu, Li-gang; Ge, Shi-jie; Wu, Jun; Ze-ji, Qiu; Qiu, Ze-ji; Zhang, Hong-chun; Chao, En-xiang; Yu, Zhuo-nan

    2014-01-01

    A Chinese medicine granule, Shu-Feng-Xuan-Fei (SFXF), is critical for viral clearance in early phase of influenza virus infection. In this study, 72 ICR mice were randomly divided into six groups: normal control group, virus control group, Oseltamivir group, low-dose SFXF, medium-dose SFXF, and high-dose SFXF. Mice were anesthetized and inoculated with 4LD50 of influenza virus A (H1N1) except normal control group. Oseltamivir group received 11.375 mg·kg−1·d−1 Oseltamivir Phosphate. SFXF 3.76, 1.88 and 0.94 g·kg−1·d−1 were administrated to mice in all SFXF groups. Each group was in equal dose of 0.2ml daily for 4 consecutive days. Mice were sacrificed and then total RNA was extracted in lung tissue. Some genes involved in T-cell-mediated immunity were selected by DNA microarray. These candidate genes were verified by Real-Time PCR and western immunoblotting. Compared with virus control group, in Toll-like receptor signaling pathway, 12 virus-altered genes were significantly reduced following medium-dose SFXF treatment. Eighteen antigen processing presentation-associated genes were upregulated by medium-dose SFXF. In the process of T cell receptor signaling pathway, 19 genes were downregulated by medium-dose SFXF treatment. On exploration into effector T cells activation and cytokines, all of altered genes in virus control group were reversed by medium-dose SFXF. Real-time PCR and western immunoblotting showed that the regulation of medium-dose SFXF in IL-4, IFN-γ, TNF-α, IL-1β, TLR7, MyD88, p38, and JNK was superior to Oseltamivir and high-dose SFXF group. Therefore, SFXF granules could reduce influenza infected cells and activation of T cells. PMID:24527057

  16. Thiol dependent NF-κB suppression and inhibition of T-cell mediated adaptive immune responses by a naturally occurring steroidal lactone Withaferin A.

    PubMed

    Gambhir, Lokesh; Checker, Rahul; Sharma, Deepak; Thoh, M; Patil, Anand; Degani, M; Gota, Vikram; Sandur, Santosh K

    2015-12-01

    Withaferin A (WA), a steroidal lactone isolated from ayurvedic medicinal plant Withania somnifera, was shown to inhibit tumor growth by inducing oxidative stress and suppressing NF-κB pathway. However, its effect on T-cell mediated adaptive immune responses and the underlying mechanism has not been investigated. Since both T-cell responses and NF-κB pathway are known to be redox sensitive, the present study was undertaken to elucidate the effect of WA on adaptive immune responses in vitro and in vivo. WA inhibited mitogen induced T-cell and B-cell proliferation in vitro without inducing any cell death. It inhibited upregulation of T-cell (CD25, CD69, CD71 and CD54) and B-cell (CD80, CD86 and MHC-II) activation markers and secretion of Th1 and Th2 cytokines. WA induced oxidative stress by increasing the basal ROS levels and the immunosuppressive effects of WA were abrogated only by thiol anti-oxidants. The redox modulatory effects of WA in T-cells were attributed to its ability to directly interact with free thiols. WA inhibited NF-κB nuclear translocation in lymphocytes and prevented the direct binding of nuclear NF-κB to its consensus sequence. MALDI-TOF analysis using a synthetic NF-κB-p50 peptide containing Cys-62 residue suggested that WA can modify the cysteine residue of NF-κB. The pharmacokinetic studies for WA were also carried out and in vivo efficacy of WA was studied using mouse model of Graft-versus-host disease. In conclusion, WA is a potent inhibitor of T-cell responses and acts via a novel thiol dependent mechanism and inhibition of NF-κB pathway. PMID:26408225

  17. Cell-mediated immunity to Toxoplasma gondii develops primarily by local Th-1 host immune responses in the absence of parasite replication1

    PubMed Central

    Gigley, Jason P.; Fox, Barbara A.; Bzik, David J.

    2008-01-01

    A single inoculation of mice with the live attenuated Toxoplasma gondii uracil auxotroph strain cps1-1 induces long-lasting immunity against lethal challenge with hyper-virulent strain RH. The mechanism for this robust immunity in the absence of parasite replication has not been addressed. The mechanism of long-lasting immunity, the importance of route of immunization, cellular recruitment to the site of infection, and local and systemic inflammation were evaluated. Our results show that infection with cps1-1 elicits long-lasting CD8+ T cell mediated immunity. We show that immunization with cps1-1 infected DCs elicits long-lasting immunity. Intraperitoneal infection with cps1-1 induced a rapid influx of GR1+ neutrophils and 2 stages of GR1+ CD68+ inflammatory monocyte infiltration into the site of inoculation. CD19+ B cells and CD3+ T cells steadily increase for 8 days after infection. CD8+ T cells were rapidly recruited to the site of infection and increased faster than CD4+ T cells. Surprisingly, cps1-1 infection induced high systemic levels of bioactive IL-12p70 and very low level and transient systemic Ifn-γ. Furthermore, we show significant levels of these inflammatory cytokines were locally produced at the site of cps1-1 inoculation. These findings offer new insight into immunological mechanisms and local host responses to a non-replicating Type I parasite infection associated with development of long-lasting immunity to Toxoplasma gondii. PMID:19124750

  18. Cell-mediated immunity to Toxoplasma gondii develops primarily by local Th1 host immune responses in the absence of parasite replication.

    PubMed

    Gigley, Jason P; Fox, Barbara A; Bzik, David J

    2009-01-15

    A single inoculation of mice with the live, attenuated Toxoplasma gondii uracil auxotroph strain cps1-1 induces long-lasting immunity against lethal challenge with hypervirulent strain RH. The mechanism for this robust immunity in the absence of parasite replication has not been addressed. The mechanism of long-lasting immunity, the importance of route of immunization, cellular recruitment to the site of infection, and local and systemic inflammation were evaluated. Our results show that infection with cps1-1 elicits long-lasting CD8+ T cell- mediated immunity. We show that immunization with cps1-1-infected dendritic cells elicits long-lasting immunity. Intraperitoneal infection with cps1-1 induced a rapid influx of GR1+ neutrophils and two stages of GR1+CD68+ inflammatory monocyte infiltration into the site of inoculation. CD19+ B cells and CD3+ T cells steadily increase for 8 days after infection. CD8+ T cells were rapidly recruited to the site of infection and increased faster than CD4+ T cells. Surprisingly, cps1-1 infection induced high systemic levels of bioactive IL-12p70 and a very low level and transient systemic IFN-gamma. Furthermore, we show significant levels of these inflammatory cytokines were locally produced at the site of cps1-1 inoculation. These findings offer new insight into immunological mechanisms and local host responses to a non-replicating type I parasite infection associated with development of long-lasting immunity to Toxoplasma gondii. PMID:19124750

  19. Dim light at night interferes with the development of the short-day phenotype and impairs cell-mediated immunity in Siberian hamsters (Phodopus sungorus).

    PubMed

    Aubrecht, Taryn G; Weil, Zachary M; Nelson, Randy J

    2014-10-01

    Winter is a challenging time to survive and breed outside of the tropics. Animals use day length (photoperiod) to regulate seasonally appropriate adaptations in anticipation of challenging winter conditions. The net result of these photoperiod-mediated adjustments is enhanced immune function and increased survival. Thus, the ability to discriminate day length information is critical for survival and reproduction in small animals. However, during the past century, urban and suburban development has rapidly expanded and filled the night sky with light from various sources, obscuring crucial light-dark signals, which alters physiological interpretation of day lengths. Furthermore, reduced space, increased proximity to people, and the presence of light at night may act as stressors for small animals. Whereas acute stressors typically enhance immune responses, chronic exposure to stressors often impairs immune responses. Therefore, we hypothesized that the combination of dim light at night and chronic stress interferes with enhanced cell-mediated immunity observed during short days. Siberian hamsters (Phodopus sungorus) were assigned to short or long days with dark nights (0 lux) or dim (5 lux) light at night for 10 weeks. Following 2 weeks of chronic restraint (6 hr/day), a model of chronic stress, delayed type hypersensitivity (DTH) responses were assessed. Both dim light at night and restraint reduced the DTH response. Dim light at night during long nights produced an intermediate short day phenotype. These results suggest the constant presence of light at night could negatively affect survival of photoperiodic rodents by disrupting the timing of breeding and immune responses. PMID:24962267

  20. The effects of chloroform, ethyl acetate and methanolic extracts of Brassica rapa L. on cell-mediated immune response in mice

    PubMed Central

    Jafarian-Dehkordi, A.; Zolfaghari, B.; Mirdamadi, M.

    2013-01-01

    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., 1×108cells/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., 1×108cells/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. PMID:24019825

  1. Cytotoxicity of commonly used luting cements -An in vitro study.

    PubMed

    Trumpaite-Vanagiene, Rita; Bukelskiene, Virginija; Aleksejuniene, Jolanta; Puriene, Alina; Baltriukiene, Daiva; Rutkunas, Vygandas

    2015-01-01

    The study aimed to 1) evaluate the cytotoxicity of luting cements: Hoffmann's Zinc Phosphate (Hoffmann's ZP), GC Fuji Plus Resin Modified Glass Ionomer (Fuji Plus RMGI) and 3M ESPE RelyX Unicem Resin Cement (RelyX Unicem RC) and 2) test if pre-washing reduces the cements' cytotoxicity. In vitro human gingival fibroblast (HGF) culture model was chosen. The cytotoxicity was evaluated by MTT test, the cell viability -by staining the cells with AO/EB dye mixture. The means±SD of Cell Survival Ratio (CSR%) were compared among different cement types under two testing conditions, with or without cement pre-washing. The CSR%s were compared by ANOVA and linear multiple regression (LMR). Hoffmann's ZPC was less cytotoxic, while Fuji Plus RMGIC and RelyX Unicem RC were more cytotoxic (ANOVA, p<0.001). The type of cement and cement pre-washing jointly explained 90% of cell survival (LMR, p<0.001, adjusted squared R=0.889). The commonly used luting cements such as Hoffmann's ZP, Fuji Plus RMGI and RelyX Unicem RC may have a cytotoxic potential. PMID:25904168

  2. Evaluation of cytotoxicity of different tobacco product preparations.

    PubMed

    Arimilli, Subhashini; Damratoski, Brad E; Bombick, Betsy; Borgerding, Michael F; Prasad, G L

    2012-12-01

    Acute exposure to cigarette smoke or its components triggers diverse cellular effects, including cytotoxicity. However, available data regarding the potential cytotoxic effects of smokeless tobacco (ST) extracts lack consensus. Here, we investigated the relative biological effects of 2S3 reference ST, and whether ST elicits differential cellular/molecular responses compared to combustible tobacco product preparations (TPPs) prepared from 3R4F cigarettes. Total particulate matter (TPM) and whole smoke conditioned medium (WS-CM) were employed as combustible TPPs, while the ST extract was used as non-combustible TPP. HL60, THP1 cells and human PBMCs were used to examine the effects of TPPs in short-term cell culture. Corresponding EC(50) values, normalized for nicotine content of the TPPs, suggest that combustible TPPs induced higher cytotoxicity as follows: WS-CM TPM ≥ ≫ST extract>nicotine. While all three TPPs induced detectable levels of DNA damage and IL8 secretion, the combustible TPPs were significantly more potent than the ST preparation. The major PBMC subsets showed differential cytotoxicity to combustible TPPs as follows: CD4>CD8>monocytes>NK cells. These findings suggest that, relative cytotoxic and other cell biological effects of TPPs are dose-dependent, and that ST extract is the least cytotoxic TPP tested in this study. PMID:22996032

  3. [Chemical constituents from Callicarpa nudiflora and their cytotoxic activities].

    PubMed

    Ma, Yan-Chun; Zhang, Min; Xu, Wen-Tong; Feng, Shi-Xiu; Lei, Ming; Yi, Bo

    2014-08-01

    The chemical consitituents from cytotoxic fraction of the Callicarpa nudiflora extract were isolated and purified by a combination of HP-20 macroporous resin, silica gel and Sephadex LH-20 column chromatographies. The structures were elucidated on the basis of the spectroscopic data and comparison of their spectroscopic data with reported data. The cytotoxicity was evaluated by the MTT assay. The 50% and 70% EtOH elutions of EtOH-extract showed significant cytotoxic activities, leading to the isolation of twelve compounds, which were identified as luteoloside(1), lutedin-4'-O-β-D-glucoside(2), 6-hydroxyluteolin-7-O-β-glucoside(3), lutedin-7-O-neohesperidoside(4), rhoifolin (5), luteolin-7, 4'-di-O-glucoside (6), forsythoside B (7), acteoside (8), alyssonoside (9), catalpol(10), nudifloside(11), and leonuride(12). Compounds 3-6, 10 and 12 were isolated from this genus for the first time, and compound 9 was isolated from this plant for the first time. The cytotoxicity assay demonstrated that flavonoids 1-6, in various concentrations, showed monolithic proliferation inhibitory activities against Hela, A549 and MCF-7 cell lines. Compounds 3, 5 and iridoid glycoside 11 possessed higher cytotoxicacivities. In short, flavonoids are the main components of cytotoxic extract from C. nudiflora, while phenylethanoid glycosides are the predominant ingredient but inactive to cancer cell lines. In addition, the minor iridoid glycoside expressed weak cytotoxic activity. PMID:25509294

  4. Permeation of cytotoxic formulations through swatches from selected medical gloves.

    PubMed

    Klein, Michael; Lambov, Nikolai; Samev, Nikola; Carstens, Gerhard

    2003-05-15

    The permeability of selected medical glove materials to various cytotoxic agents is described. Fifteen cytotoxic agents were prepared at the highest concentrations normally encountered by hospital personnel. Four single-layer and two double-layer glove systems made of two materials--latex and neoprene--were exposed to the drugs for 30, 60, 90, 120, 150, and 180 minutes. Circular sections of the glove material were cut from the cuff and evaluated without any pretreatment. Permeability tests were conducted in an apparatus consisting of a donor chamber containing the cytotoxic solution and a collection chamber filled with water (the acceptor medium). The two sections were separated by the glove material. Permeating portions, collected in water as the acceptor medium, were analyzed by either ultraviolet-visible light spectrophotometry or high-performance liquid chromatography (HPLC). Permeation rates were calculated on the basis of the concentration of the cytotoxic agent in the acceptor medium. Spectrophotometric measurements were taken every 30 minutes, and HPLC analysis was performed at the end of the three-hour period. Average permeation rates for 14 drugs were low (< 0.2 nmol/[min.cm2]) or no permeation was detected in all glove materials. All glove materials tested were impermeable to most of the cytotoxic agents over a period of three hours. Carmustine was the only agent that substantially permeated single-layer latex glove materials. Permeation of most tested cytotoxic formulations was low through swatches of material from various medical gloves. PMID:12789871

  5. Induction of Cytotoxicity through Photorelease of Aminoferrocene.

    PubMed

    Leonidova, Anna; Anstaett, Philipp; Pierroz, Vanessa; Mari, Cristina; Spingler, Bernhard; Ferrari, Stefano; Gasser, Gilles

    2015-10-19

    Reactive oxygen species (ROS)-activated aminoferrocene-based anticancer prodrug candidates successfully take advantage of intrinsically high amounts of ROS in tumor tissues. Interestingly, the ROS-initiated activation of these prodrug candidates leads to formation of unstable aminoferrocene (Fc-NH2) derivatives, which decay to iron ions. The latter catalytically increases ROS concentration to a lethal level. In this work, we prepared light-controlled aminoferrocene prodrug candidates by derivatizing Fc-NH2 with an o-nitrophenyl and an o-nitrobiphenyl photolabile protecting group (PLPG), respectively, and by further conjugation to a mitochondria localization signal (MLS) peptide (Cys-D-Arg-Phe-Lys-NH2). The resulting bioconjugates were found to be more stable and less cytotoxic, in the dark, toward human promyelocytic leukemia cells (HL-60) compared to Fc-NH2. Upon light irradiation at 355 nm, both conjugates released Fc-NH2, albeit with very different photolysis quantum yields. The o-nitrobiphenyl photocage was in fact several orders of magnitude more efficient than the o-nitrophenyl photocage in releasing Fc-NH2. This difference was reflected by the light irradiation experiments on the HL-60 cell line, in which aminoferrocene conjugated with the o-nitrobiphenyl cage and the MLS displayed the highest phototoxicity index (2.5 ± 0.4) of all the compounds tested. The iron release assays confirmed the rise in iron ion concentrations upon light irradiation of both caged aminoferrocene derivatives. Together with the absence of phototoxicity on the nonmalignant hTERT-immortalized retinal pigment epithelial (hTERT RPE-1) cell line, these results indicate catalytic generation of ROS as possible mode of action. PMID:26440628

  6. Cytotoxicity of titanium and silicon dioxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Wagner, Stefanie; Münzer, Simon; Behrens, Peter; Scheper, Thomas; Bahnemann, Detlef; Kasper, Cornelia

    2009-05-01

    Different TiO2 and SiO2 nanoparticles have been tested concerning their toxicity on selected mammalian cell lines. Various powders and suspensions, all of which consist of titanium or silicon dioxide nanoparticles have been examined. These particles differ in the crystal structure, the size and the BET-surface area. There was also a classification in fixed particles and in particles easily accessible in solution. With focus on the possible adsorption of the nanoparticles into the human organism, via skin and via respiratory tract, the effects on fibroblasts (NIH-3T3) and on a human lung adenocarcinoma epithelial cell line were examined. Additionally, the particles were tested with HEP-G2 cells, which are often used as model cell line for biocompatibility tests, and PC-12 cells, a rat adrenal pheochromocytoma cell line. The viability of the cells was examined by the MTT-test. The viability results were found to partly depend on the type of cells used. The experimental results show that the adhesion of the cells on the different powders strongly depends on the type of cell lines as well as on the type of powder. It was found that the lower viability of some cells on the powder coatings is not only caused by a cytotoxicity effect of the powders, but is also due to a lower adhesion of the cells on the particle surfaces. Furthermore, it could be shown that the physical properties of the powders cannot be easily correlated to any observed biological effect. While some powders show a significant suppression of the cell growth, others with similar physical properties indicate no toxic effect.

  7. Neurobiological changes by cytotoxic agents in mice.

    PubMed

    Seigers, R; Loos, M; Van Tellingen, O; Boogerd, W; Smit, A B; Schagen, S B

    2016-02-15

    Cognitive deficit is a frequently reported side-effect of adjuvant chemotherapy. A large number of animal studies has been performed to examine the neurobiological mechanisms underlying this phenomenon, however, definite conclusions from these studies are restricted due to differences in experimental set-up. We systematically investigated the effects of 6 cytotoxic agents on various neurobiological parameters. C57Bl/6J mice were treated with cyclophosphamide, docetaxel, doxorubicin, 5-fluorouracil, methotrexate, or topotecan. The animals were sacrificed 3 or 15 weeks after treatment and the effect on neurogenesis, blood vessel density, and neuroinflammation was analyzed using immunohistochemistry. None of the cytostatic agents tested affected neurogenesis (cell survival or cell proliferation). Blood vessel density was increased in the hippocampus and prefrontal cortex 3 weeks after treatment with docetaxel and doxorubicin compared with control animals. A decrease in the number of microglial cells was observed in the prefrontal cortex after treatment with cyclophosphamide, docetaxel, 5-FU, and topotecan compared with control mice. The observed decrease in microglia cells is indicative of inflammation that occurred after treatment. Overall, the magnitude of the effects was relatively modest. Therefore, we conducted a similar study with topotecan in Abcg2;Abcb1a/b knock out and wildtype FVB mice. Animals were sacrificed 3 weeks after treatment and no notable effect was seen in hippocampal cell differentiation (DCX), microglia activation, or blood vessel density. Perhaps the FVB strain is more resistant to the neurotoxic effects of topotecan which makes this not the correct model to study the mechanism of chemotherapy-induced cognitive impairment. PMID:26602283

  8. Human Sulfotransferases Enhance the Cytotoxicity of Tolvaptan.

    PubMed

    Fang, Jia-Long; Wu, Yuanfeng; Gamboa da Costa, Gonçalo; Chen, Si; Chitranshi, Priyanka; Beland, Frederick A

    2016-03-01

    Tolvaptan, a vasopressin receptor 2 antagonist used to treat hyponatremia, has recently been reported to be associated with liver injury. Sulfotransferases (SULTs) have been implicated as important detoxifying and/or activating enzymes for numerous xenobiotics, drugs, and endogenous compounds. To characterize better the role of SULTs in tolvaptan metabolism, HEK293 cells stably overexpressing 12 human SULTs were generated. Using these cell lines, the extent of tolvaptan sulfate formation was assessed by reversed-phase high-performance liquid chromatography through comparison to a synthetic standard. Of the 12 known human SULTs, no detectable sulfation of tolvaptan was observed with SULT1A1, SULT1A2, SULT1A3, SULT1C2, SULT1C4, SULT4A1, or SULT6B1. The affinity of individual SULT isozymes, as determined by Km analysis, was SULT1C3 > SULT2A1 > SULT2B1 ∼ SULT1B1 > SULT1E1. The half inhibitory concentration of tolvaptan on cell growth in HEK293/SULT1C3 cells and HEK293/CYP3A4 & SULT1C3 cells was significantly lower than that in the corresponding HEK293/vector cells or HEK293/CYP3A4 & SULT vector cells. Moreover, exposing cells to tolvaptan in the presence of cyclosporine A, an inhibitor of the drug efflux transporters, significantly increased the intracellular levels of tolvaptan sulfate and decreased the cell viability in HEK293/SULT1C3 cells. These data indicate that sulfation increased the cytotoxicity of tolvaptan. PMID:26660633

  9. Differential inhibition of trastuzumab- and cetuximab-induced cytotoxicity of cancer cells by immunoglobulin G1 expressing different GM allotypes.

    PubMed

    Namboodiri, A M; Pandey, J P

    2011-12-01

    Antibody-dependent cell-mediated cytotoxicity (ADCC), which links the innate and the adaptive arms of immunity, is a major host immunosurveillance mechanism against tumours, as well as the leading mechanism underlying the clinical efficacy of therapeutic antibodies such as cetuximab and trastuzumab, which target tumour antigens, human epidermal growth factor receptor (HER)1 and HER2, respectively. Immunoglobulin (Ig)G antibody-mediated ADCC is triggered upon ligation of Fcγ receptor (FcγR) to the Fc region of IgG molecules. It follows that genetic variation in FcγR and Fc could contribute to the differences in the magnitude of ADCC. Genetic variation in FcγR is known to contribute to the differences in the magnitude of ADCC, but the contribution of natural genetic variation in Fc, GM allotypes, in this interaction has hitherto not been investigated. Using an ADCC inhibition assay, we show that IgG1 expressing the GM 3+, 1-, 2- allotypes was equally effective in inhibiting cetuximab- and trastuzumab-mediated ADCC of respective target cells, in the presence of natural killer (NK) cells expressing either valine or phenylalanine allele of FcγRIIIa. In contrast, IgG1 expressing the allelic GM 17+, 1+, 2+ allotypes was significantly more effective in inhibiting the ADCC - mediated by both monoclonal antibodies - when NK cells expressed the valine, rather than the phenylalanine, allele of FcγRIIIa. These findings have important implications for engineering antibodies (with human γ1 constant region) against malignancies characterized by the over-expression of tumour antigens HER1 and HER2 - especially for patients who, because of their FcγRIIIa genotype, are unlikely to benefit from the currently available therapeutics. PMID:22059994

  10. Critical role of the NKG2D receptor for NK cell-mediated control and immune escape of B-cell lymphoma.

    PubMed

    Belting, Lena; Hömberg, Nadine; Przewoznik, Margarethe; Brenner, Christoph; Riedel, Tanja; Flatley, Andrew; Polić, Bojan; Busch, Dirk H; Röcken, Martin; Mocikat, Ralph

    2015-09-01

    Little is known on the control of lymphomas by NK cells. Here, we study the role of the NK group 2D (NKG2D) receptor for the immunosurveillance of lymphoma. By using transplantable tumors as well as a λ-myc-transgenic model of endogenously arising lymphoma and NKG2D-deficient mice, we show that NK cells eliminate tumor cells in vivo after receiving two signals. One step involved the activation of NK cells giving rise to IFN-γ expression, which was effected by MHCI(low) tumor cells or DCs. However, this was necessary but not sufficient to mediate cytotoxicity. Triggering cytotoxicity additionally required a second step, which could be mediated by engagement of the NKG2D receptor. Thus, NKG2D-deficient NK cells could become activated in vivo, but they were not able to reject transplanted lymphomas or to degranulate in animals bearing autochthonous lymphomas. Tumor growth in NKG2D-deficient λ-myc-transgenic mice was significantly accelerated compared to NKG2D-competent animals. Whereas the latter developed tumors that lost expression of NKG2D ligands (NKG2D-L) in late disease stages, this did not occur in NKG2D-deficient mice. This indicates that NK cells and the NKG2D receptor play a role for control of lymphomas and that selection for NKG2D-L loss mutants provides a mechanism of tumor escape. PMID:26151313

  11. Augmentation of natural killer cell and antibody-dependent cellular cytotoxicity in BALB/c mice by sulforaphane, a naturally occurring isothiocyanate from broccoli through enhanced production of cytokines IL-2 and IFN-gamma.

    PubMed

    Thejass, P; Kuttan, G

    2006-01-01

    Effect of sulforaphane on cell-mediated immune (CMI) response was studied in normal as well as Ehrlich ascites tumor-bearing BALB/c mice. Administration of sulforaphane significantly enhanced natural killer (NK) cell activity in both normal as well as tumor-bearing animals, and the activity was observed earlier than in tumor-bearing control animals. Antibody-dependent cellular cytotoxicity (ADCC) also was enhanced significantly in both normal as well as tumor-bearing animals after sulforaphane administration compared with untreated control tumor-bearing animals. An early antibody-dependent complement-mediated cytotoxicity (ACC) also was observed in sulforaphane-treated normal and tumor-bearing animals. Administration of sulforaphane significantly enhanced the production of Interleukin-2 and Interferon-gamma in normal as well as tumor-bearing animals. In addition, sulforaphane significantly enhanced the proliferation of splenocytes, bone marrow cells, and thymocytes by stimulating the mitogenic potential of various mitogens such as concanavalin A, phytohaemagglutinin, poke weed mitogen, and lipopolysaccharide. PMID:16997793

  12. Dissociation of TNF-alpha cytotoxic and proinflammatory activities by p55 receptor- and p75 receptor-selective TNF-alpha mutants.

    PubMed Central

    Barbara, J A; Smith, W B; Gamble, J R; Van Ostade, X; Vandenabeele, P; Tavernier, J; Fiers, W; Vadas, M A; Lopez, A F

    1994-01-01

    Human tumour necrosis factor alpha (TNF-alpha) is a pleiotropic cytokine capable of killing mammalian tumour cells in vitro and in vivo, and of enhancing the proinflammatory activity of leucocytes and endothelium, the latter effects limiting its usage as an antitumour agent in humans. Using TNF-alpha mutants with a selective capacity to bind to the TNF p55 receptor (TNFR55) or to the p75 receptor (TNFR75) we show here that these two major activities of TNF-alpha can be dissociated. The TNFR55-selective mutants (R32W, E146K and R32W-S86T) which bind poorly to TNFR75 displayed similar potency to wild-type TNF in causing cytotoxicity of a human laryngeal carcinoma-derived cell line (HEp-2) and cytostasis in a human leukaemic cell line (U937). However, these TNFR55-selective mutants exhibited lower proinflammatory activity than wild-type TNF. Specifically, TNF-alpha's priming of human neutrophils for superoxide production and antibody-dependent cell-mediated cytotoxicity, platelet-activating factor synthesis and adhesion to endothelium were reduced by up to 170-fold. Activation of human endothelial cell functions represented by human umbilical venular endothelial cell (HUVEC) adhesiveness for neutrophils, E-selectin expression, neutrophil transmigration and IL-8 secretion were also reduced by up to 280-fold. On the other hand, D143F, a TNFR75-selective mutant tested either alone or in combination with TNFR55-selective mutants, did not stimulate these activities despite being able to cause cytokine production in TNFR75-transfected PC60 cells.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7509279

  13. Effects of p56lck deficiency on the growth and cytolytic effector function of an interleukin-2-dependent