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Sample records for cell responses evidence

  1. Primary immune system responders to nucleus pulposus cells: evidence for immune response in disc herniation

    Directory of Open Access Journals (Sweden)

    K Murai

    2010-01-01

    Full Text Available Although intervertebral disc herniation and associated sciatica is a common disease, its molecular pathogenesis is not well understood. Immune responses are thought to be involved. This study provides direct evidence that even non-degenerated nucleus pulposus (NP cells elicit immune responses. An in vitro colony forming inhibition assay demonstrated the suppressive effects of autologous spleen cells on NP cells and an in vitro cytotoxicity assay showed the positive cytotoxic effects of natural killer (NK cells and macrophages on NP cells. Non-degenerated rat NP tissues transplanted into wild type rats and immune-deficient mice demonstrated a significantly higher NP cell survival rate in immune-deficient mice. Immunohistochemical staining showed the presence of macrophages and NK cells in the transplanted NP tissues. These results suggest that even non-degenerated autologous NP cells are recognized by macrophages and NK cells, which may have an immunological function in the early phase of disc herniation. These findings contribute to understanding resorption and the inflammatory reaction to disc herniation.

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

    Science.gov (United States)

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

    2018-01-01

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

  3. Suppression of in vitro primary immune response by L1210 cells and their culture supernatant: evidence for cytotoxic effects

    International Nuclear Information System (INIS)

    Huget, R.P.; Flad, H.D.; Opitz, H.G.

    1977-01-01

    L1210 cells and their culture supernatants were found to inhibit the generation of PFC in the in vitro primary immune response of spleen cells to SRBC. As few as 1 percent of L1210 cells and 1 percent of culture fluid were inhibitory. Inhibition of DNA or protein synthesis of L1210 cells did not abolish their immunosuppressive activity, excluding exhaustion of culture medium as a possible mechanism of inhibition of PFC. Heating of the supernatant completely abrogated the suppressive effect and resulted in a marked increase of PFC. Daily evaluation of cell viability in the cultures revealed that, in the presence of L1210 and supernatants, the fraction of surviving cells is markedly reduced. We conclude that a direct cytotoxic effect on splenic lymphocytes and macrophages is the predominant immunosuppressive mechanism of L1210 cells and their culture supernatants

  4. Evidence for a role of Collapsin response mediator protein-2 in signaling pathways that regulate the proliferation of non-neuronal cells

    International Nuclear Information System (INIS)

    Tahimic, Candice Ginn T.; Tomimatsu, Nozomi; Nishigaki, Ryuichi; Fukuhara, Akiko; Toda, Tosifusa; Kaibuchi, Kozo; Shiota, Goshi; Oshimura, Mitsuo; Kurimasa, Akihiro

    2006-01-01

    Collapsin response mediator protein-2 or Crmp-2 plays a critical role in the establishment of neuronal polarity. In this study, we present evidence that apart from its functions in neurodevelopment, Crmp-2 is also involved in pathways that regulate the proliferation of non-neuronal cells through its phosphorylation by regulatory proteins. We show that Crmp-2 undergoes dynamic phosphorylation changes in response to contact inhibition-induced quiescence and that hyperphosphorylation of Crmp-2 occurs in a tumor. We further suggest that de-regulation of Crmp-2 phosphorylation levels at certain amino acid residues may lead to aberrant cell proliferation and consequently, tumorigenesis

  5. Evidence for induction of DNA double strand breaks in the bystander response to targeted soft X-rays in repair deficient CHO cells

    International Nuclear Information System (INIS)

    Kashino, Genro; Suzuki, Keiji; Prise, K.M.

    2005-01-01

    Evidence is accumulating that irradiated cells produce some signals which interact with non-exposed cells in the same population. Here, we analysed the mechanism of such a bystander effect from targeted cells to non-targeted cells. Firstly, in order to investigate the bystander effect in Chinese hamster ovary (CHO) cell lines we irradiated a single cell within a population and scored the formation of micronuclei. When a single nucleus in the population, of double strand break repair deficient xrs5 cells, was targeted with 1 Gy of Al-K soft X-rays, elevated numbers of micronuclei were induced in the neighbouring unirradiated cells. The induction of micronuclei was also observed when conditioned medium was transferred from irradiated to non-irradiated xrs5 cells. These results suggest that DNA double strand breaks are caused by factors secreted in the medium from irradiated cells. To clarify the involvements of radical species in the bystander response, cells were treated with 0.5%DMSO 1 hour before irradiation and then bystander effects were estimated in xrs5 cells. The results showed clearly that DMSO treatment during X-irradiation suppress the induction of micronuclei in bystander xrs5 cells, when conditioned medium was transferred from irradiated xrs5 cells. Therefore, it is suggested that radical species induced by ionizing radiation are important for producing bystander signals. (author)

  6. H-2 restriction of the T cell response to chemically induced tumors: evidence from F1 → parent chimeras

    International Nuclear Information System (INIS)

    Lannin, D.R.; Yu, S.; McKhann, C.F.

    1982-01-01

    It has been well established that T cells that react to tumor antigen on virus-induced tumors must share H-2D or H-2K specificities with the tumor. It has been impossible to perform similar studies with chemically induced tumors because each chemically induced tumor expresses a unique tumor antigen that cannot be studied in association with other H-2 types. This study provies evidence that H-2 recognition is also necessary for recognition of chemically induced tumors. We have found that F 1 → parent chimeras preferentially recognize chemically induced tumors of parental H-2 type. C3H/HeJ and C57BL/6 mice were lethally irradiated and restored with (C3H x C57BL/6) F 1 hybrid bone marrow. The F 1 → C3H chimera but not the F 1 → C57BL/6 chimera was able to respond to a C3H fibrosarcoma in mixed lymphocyte-tumor cell culture and also to neutralize the tumor in an in vivo tumor neutralization assay. On the other hand, the F 1 → C57BL/6 chimera but not the F 1 → C3H chimera was able to kill the C57BL/6 lymphoma EL4 in an in vitro cytotoxicity assay. Both chimeras were tolerant to C3H and C57BL/6 alloantigens but could respond normally to Con A and to BALB/c spleen cells in mixed lymphocyte cultures and cytotoxicity assay

  7. Cell response to surgery.

    LENUS (Irish Health Repository)

    Ni Choileain, Niamh

    2012-02-03

    OBJECTIVES: To describe the profound alterations in host immunity that are produced by major surgery as demonstrated by experimental and clinical studies, and to evaluate the benefits of therapeutic strategies aimed at attenuating perioperative immune dysfunction. DATA SOURCES: A review of the English-language literature was conducted, incorporating searches of the MEDLINE, EMBASE, and Cochrane collaboration databases to identify laboratory and clinical studies investigating the cellular response to surgery. STUDY SELECTION: Original articles and case reports describing immune dysfunction secondary to surgical trauma were included. DATA EXTRACTION: The results were compiled to show outcomes of different studies and were compared. DATA SYNTHESIS: Current evidence indicates that the early systemic inflammatory response syndrome observed after major surgery that is characterized by proinflammatory cytokine release, microcirculatory disturbance, and cell-mediated immune dysfunction is followed by a compensatory anti-inflammatory response syndrome, which predisposes the patient to opportunistic infection, multiple organ dysfunction syndrome, and death. Because there are currently no effective treatment options for multiple organ dysfunction syndrome, measures to prevent its onset should be initiated at an early stage. Accumulating experimental evidence suggests that targeted therapeutic strategies involving immunomodulatory agents such as interferon gamma, granulocyte colony-stimulating factor, the prostaglandin E(2) antagonist, indomethacin, and pentoxifylline may be used for the treatment of systemic inflammatory response syndrome to prevent the onset of multiple organ dysfunction syndrome. CONCLUSIONS: Surgical trauma produces profound immunological dysfunction. Therapeutic strategies directed at restoring immune homeostasis should aim to redress the physiological proinflammatory-anti-inflammatory cell imbalance associated with major surgery.

  8. Modulation of the heterogeneous membrane potential response of neutrophils to N-formyl-methionyl-leucyl-phenylalanine (FMLP) by leukotriene B4: evidence for cell recruitment

    International Nuclear Information System (INIS)

    Fletcher, M.P.

    1986-01-01

    Individual human neutrophils (PMN) isolated by Hypaque-Ficoll gradient sedimentation, dextran sedimentation, or buffy coat preparation were assessed for the effects of leukotriene B4 (5S,12R dihydroxy 6,14-cis-8, 10 trans eicosatetraenoic acid (LTB4)-pretreatment on N-formylmethionyl-leucyl-phenylalanine (FMLP)-mediated membrane potential or oxidative responses by using flow cytometry and a lipophilic probe of membrane potential (di-pentyl-oxacarbocyanine, di-O-C(5)3), or the nitroblue tetrazolium dye (NBT) reduction test, respectively. Although exposure to LTB4 (10(-7) M) had no effect on the membrane potential of resting PMN and little effect on oxidant production, pretreating PMN with LTB4 followed by FMLP (10(-6) M) demonstrated a significant enhancement in the proportion of depolarizing PMN over that seen with FMLP alone (p = 0.0014, N = 9). This recruitment of previously unresponsive cells by LTB4 was dose and time dependent, with the maximal relative increase in the proportion of depolarizing cells occurring at LTB4 concentrations of 10(-8) to 10(-7) M and within 1 min of LTB4 addition. The recruitment effect persisted despite vigorous washing of the cells. LTB4 also increased the proportion of NBT-positive PMN in response to FMLP. Although LTB4 alone did not depolarize PMN it did induce a light scatter shift indicative of cell activation. 3 H-FMLP binding studied at 0 degree C comparing buffer and LTB4-treated PMN indicated no significant change in the number or affinity of FMLP binding. The data provide evidence for the recruitment of a greater proportion of cells into a FMLP-responsive state as a mechanism for the enhanced functional response of PMN pretreated with LTB4, as well as for a dissociation of the membrane potential and light scattering responses of cells to this pro-inflammatory LT

  9. Adjuvant therapeutic vaccination in patients with non-small cell lung cancer made lymphopenic and reconstituted with autologous PBMC: first clinical experience and evidence of an immune response

    Directory of Open Access Journals (Sweden)

    Schendel Dolores J

    2007-09-01

    Full Text Available Abstract Background Given the considerable toxicity and modest benefit of adjuvant chemotherapy for non-small cell lung cancer (NSCLC, there is clearly a need for new treatment modalities in the adjuvant setting. Active specific immunotherapy may represent such an option. However, clinical responses have been rare so far. Manipulating the host by inducing lymphopenia before vaccination resulted in a magnification of the immune response in the preclinical setting. To evaluate feasibility and safety of an irradiated, autologous tumor cell vaccine given following induction of lymphopenia by chemotherapy and reinfusion of autologous peripheral blood mononuclear cells (PBMC, we are currently conducting a pilot-phase I clinical trial in patients with NSCLC following surgical resection. This paper reports on the first clinical experience and evidence of an immune response in patients suffering from NSCLC. Methods NSCLC patients stages I-IIIA are recruited. Vaccines are generated from their resected lung specimens. Patients undergo leukapheresis to harvest their PBMC prior to or following the surgical procedure. Furthermore, patients receive preparative chemotherapy (cyclophosphamide 350 mg/m2 and fludarabine 20 mg/m2 on 3 consecutive days for induction of lymphopenia followed by reconstitution with their autologous PBMC. Vaccines are administered intradermally on day 1 following reconstitution and every two weeks for a total of up to five vaccinations. Granulocyte-macrophage-colony-stimulating-factor (GM-CSF is given continuously (at a rate of 50 μg/24 h at the site of vaccination via minipump for six consecutive days after each vaccination. Results To date, vaccines were successfully manufactured for 4 of 4 patients. The most common toxicities were local injection-site reactions and mild constitutional symptoms. Immune responses to chemotherapy, reconstitution and vaccination are measured by vaccine site and delayed type hypersensitivity (DTH skin

  10. Association of FKBP51 with priming of autophagy pathways and mediation of antidepressant treatment response: evidence in cells, mice, and humans.

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    Nils C Gassen

    2014-11-01

    Full Text Available FK506 binding protein 51 (FKBP51 is an Hsp90 co-chaperone and regulator of the glucocorticoid receptor, and consequently of stress physiology. Clinical studies suggest a genetic link between FKBP51 and antidepressant response in mood disorders; however, the underlying mechanisms remain elusive. The objective of this study was to elucidate the role of FKBP51 in the actions of antidepressants, with a particular focus on pathways of autophagy.Established cell lines, primary neural cells, human blood cells of healthy individuals and patients with depression, and mice were treated with antidepressants. Mice were tested for several neuroendocrine and behavioral parameters. Protein interactions and autophagic pathway activity were mainly evaluated by co-immunoprecipitation and Western blots. We first show that the effects of acute antidepressant treatment on behavior are abolished in FKBP51 knockout (51KO mice. Autophagic markers, such as the autophagy initiator Beclin1, were increased following acute antidepressant treatment in brains from wild-type, but not 51KO, animals. FKBP51 binds to Beclin1, changes decisive protein interactions and phosphorylation of Beclin1, and triggers autophagic pathways. Antidepressants and FKBP51 exhibited synergistic effects on these pathways. Using chronic social defeat as a depression-relevant stress model in combination with chronic paroxetine (PAR treatment revealed that the stress response, as well as the effects of antidepressants on behavior and autophagic markers, depends on FKBP51. In human blood cells of healthy individuals, FKBP51 levels correlated with the potential of antidepressants to induce autophagic pathways. Importantly, the clinical antidepressant response of patients with depression (n = 51 could be predicted by the antidepressant response of autophagic markers in patient-derived peripheral blood lymphocytes cultivated and treated ex vivo (Beclin1/amitriptyline: r = 0.572, p = 0.003; Beclin1/PAR: r

  11. Evidence for induction of DNA double strand breaks in the bystander response to targeted soft X-rays in CHO cells

    International Nuclear Information System (INIS)

    Kashino, Genro; Prise, Kevin M.; Schettino, Giuseppe; Folkard, Melvyn; Vojnovic, Borivoj; Michael, Barry D.; Suzuki, Keiji; Kodama, Seiji; Watanabe, Masami

    2004-01-01

    This study investigated the role of DNA double strand breaks and DNA base damage in radiation-induced bystander responses in Chinese hamster ovary (CHO) cell lines. Two CHO repair-deficient clones, xrs5 (DNA double strand break repair-deficient) and EM9 (DNA base excision repair-deficient) were used in addition to the wild type (CHO). The Gray Cancer Institute ultrasoft X-ray microprobe is a powerful tool for investigating the bystander response, because it permits the irradiation of only a single nucleus of a cell, as reported previously. In order to investigate the bystander effect in each repair-deficient cell line, we irradiated a single cell within a population and scored the formation of micronuclei. When a single nucleus in the population was targeted with 1 Gy, elevated numbers of micronuclei were induced in the neighbouring unirradiated cells in the EM9 and xrs5 cell lines, whereas induction was not observed in CHO. The induction of micronuclei in xrs5 was significantly higher than that in EM9. Under these conditions, the surviving fraction in the neighbouring cells was significantly lower in xrs5 than in the other cell lines, showing a higher cell killing effect in xrs5. To confirm that bystander factors secreted from irradiated cells caused these effects, we carried out medium transfer experiments using conventional X-irradiation. Medium conditioned for 24 h with irradiated cells was transferred to unirradiated cells and elevated induction of micronuclei was observed in xrs5. These results suggest that DNA double strand breaks rather than base damage are caused by factors secreted in the medium from irradiated cells

  12. Genetic control of murine T cell proliferative responses to Mycobacterium leprae. V. Evidence for cross-reactivity between host antigens and Mycobacterium leprae

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    Harris, D.P.; Jones, A.G.; Wade, S.; Krahenbuhl, J.L.; Gillis, T.P.; Watson, J.D.

    1988-09-01

    T cell proliferative responses to Mycobacterium leprae were measured by immunization of mice at the base of the tail with Ag and challenging lymphocytes from draining lymph nodes in culture with M. leprae. C57BL/10J and B10.BR mice were identified as low responder mice and the congenic strains B10.M, B10.Q, and B10.AKM as high responders whereas F1 (high x low) hybrid mice were found to be low responders. The cellular basis of low responsiveness did not appear to result from a defect in Ag-presenting cells or the activation of suppressor T cells by M. leprae. The influence of the environment in which T cells developed on responsiveness to M. leprae was analyzed in chimeric mice prepared by irradiating F1(C57BL/10J x B10.M) mice and reconstituting with bone marrow from C57BL/10J, B10.M, or F1 donors. Six weeks later, chimeric mice were immunized with M. leprae, lymph node cells were subsequently prepared, and H-2 phenotyped and challenged in culture with M. leprae Ag. T cell proliferative responses were found to be low in all cases, similar to those observed using lymph node cells from F1 hybrid mice. These results suggested that high responder B10.M lymphocytes developing in the irradiated F1 mice became tolerized to antigenic determinants found on M. leprae. This implied cross-reactive epitopes existed between some mouse strains and M. leprae. Low responsiveness to M. leprae in low responder and F1 hybrid mice may result from tolerance to H-2-encoded Ag that show cross-reactivity with M. leprae.

  13. Genetic control of murine T cell proliferative responses to Mycobacterium leprae. V. Evidence for cross-reactivity between host antigens and Mycobacterium leprae

    International Nuclear Information System (INIS)

    Harris, D.P.; Jones, A.G.; Wade, S.; Krahenbuhl, J.L.; Gillis, T.P.; Watson, J.D.

    1988-01-01

    T cell proliferative responses to Mycobacterium leprae were measured by immunization of mice at the base of the tail with Ag and challenging lymphocytes from draining lymph nodes in culture with M. leprae. C57BL/10J and B10.BR mice were identified as low responder mice and the congenic strains B10.M, B10.Q, and B10.AKM as high responders whereas F1 (high x low) hybrid mice were found to be low responders. The cellular basis of low responsiveness did not appear to result from a defect in Ag-presenting cells or the activation of suppressor T cells by M. leprae. The influence of the environment in which T cells developed on responsiveness to M. leprae was analyzed in chimeric mice prepared by irradiating F1(C57BL/10J x B10.M) mice and reconstituting with bone marrow from C57BL/10J, B10.M, or F1 donors. Six weeks later, chimeric mice were immunized with M. leprae, lymph node cells were subsequently prepared, and H-2 phenotyped and challenged in culture with M. leprae Ag. T cell proliferative responses were found to be low in all cases, similar to those observed using lymph node cells from F1 hybrid mice. These results suggested that high responder B10.M lymphocytes developing in the irradiated F1 mice became tolerized to antigenic determinants found on M. leprae. This implied cross-reactive epitopes existed between some mouse strains and M. leprae. Low responsiveness to M. leprae in low responder and F1 hybrid mice may result from tolerance to H-2-encoded Ag that show cross-reactivity with M. leprae

  14. Comparison of P2 purinergic receptors of aortic endothelial cells with those of adrenal medulla: evidence for heterogeneity of receptor subtype and of inositol phosphate response.

    Science.gov (United States)

    Allsup, D J; Boarder, M R

    1990-07-01

    Vascular endothelial cells from different parts of the circulation are known to show different functional responses, presumably corresponding to physiological roles. Previous studies have shown that ATP acts on P2 purinergic receptors of endothelial cells of major blood vessels, stimulating the formation of inositol phosphates. Here we have compared the action of ATP and congeners acting on endothelial cells of bovine thoracic aorta with cells derived from the microvasculature of bovine adrenal medulla. With measurement of total inositol phosphates, cells from the aorta showed a rank order of agonist potency of 2-methylthio-ATP greater than adenosine 5'-O-(3-thiotriphosphate) (ATP gamma S) greater than ADP greater than ATP greater than beta, gamma-imido-ATP greater than beta, gamma-methylene-ATP, consistent with action at receptors of the P2Y subtype. However, with adrenal cells the rank order of potency was ATP gamma S greater than ATP greater than beta, gamma-imido-ATP greater than ADP greater than beta, gamma-methylene-ATP = 2-methylthio-ATP. This profile is not consistent with either P2X or P2Y receptors. When the nature of this inositol phosphate response was analyzed with anion exchange chromatography, it was found that the aortic cells showed an inositol trisphosphate stimulation that peaked within a few seconds and rapidly declined, whereas the response of the adrenal medulla cells continued to rise through 5 min. Analysis of isomers of inositol phosphates revealed a different pattern of metabolism between the two cell types, which may account for the different time course of response. With adrenal cells, ATP at low micromolar concentrations caused a dose-dependent increase in levels of cyclic AMP and had a greater than additive effect on cyclic AMP levels when combined with submaximal stimulation by prostaglandin E2. These results suggest the presence of a P2Y receptor on aortic endothelial cells, with an 'atypical' purinocepter, i.e., neither P2X nor P2Y

  15. NKT Cell Responses to B Cell Lymphoma.

    Science.gov (United States)

    Li, Junxin; Sun, Wenji; Subrahmanyam, Priyanka B; Page, Carly; Younger, Kenisha M; Tiper, Irina V; Frieman, Matthew; Kimball, Amy S; Webb, Tonya J

    2014-06-01

    Natural killer T (NKT) cells are a unique subset of CD1d-restricted T lymphocytes that express characteristics of both T cells and natural killer cells. NKT cells mediate tumor immune-surveillance; however, NKT cells are numerically reduced and functionally impaired in lymphoma patients. Many hematologic malignancies express CD1d molecules and co-stimulatory proteins needed to induce anti-tumor immunity by NKT cells, yet most tumors are poorly immunogenic. In this study, we sought to investigate NKT cell responses to B cell lymphoma. In the presence of exogenous antigen, both mouse and human NKT cell lines produce cytokines following stimulation by B cell lymphoma lines. NKT cell populations were examined ex vivo in mouse models of spontaneous B cell lymphoma, and it was found that during early stages, NKT cell responses were enhanced in lymphoma-bearing animals compared to disease-free animals. In contrast, in lymphoma-bearing animals with splenomegaly and lymphadenopathy, NKT cells were functionally impaired. In a mouse model of blastoid variant mantle cell lymphoma, treatment of tumor-bearing mice with a potent NKT cell agonist, α-galactosylceramide (α-GalCer), resulted in a significant decrease in disease pathology. Ex vivo studies demonstrated that NKT cells from α-GalCer treated mice produced IFN-γ following α-GalCer restimulation, unlike NKT cells from vehicle-control treated mice. These data demonstrate an important role for NKT cells in the immune response to an aggressive hematologic malignancy like mantle cell lymphoma.

  16. T-cell response in human leishmaniasis

    DEFF Research Database (Denmark)

    Kharazmi, A; Kemp, K; Ismail, A

    1999-01-01

    In the present communication we provide evidence for the existence of a Th1/Th2 dichotomy in the T-cell response to Leishmania antigens in human leishmaniasis. Our data suggest that the pattern of IL-4 and IFN-gamma response is polarised in these patients. Lymphocytes from individuals recovered...... from cutaneous leishmaniasis (CL) responded by IFN-gamma production following stimulation with Leishmania antigens whereas cells from patients recovered from visceral leishmaniasis (VL) showed a mixed pattern of IFN-gamma and IL-4 responses. The cells producing these cytokines were predominantly CD4......+. Furthermore, IL-10 plays an important role in the development of post kala azar dermal leishmaniasis (PKDL) from VL. The balance between the parasitic-specific T-cell response plays an important regulatory role in determining the outcome of Leishmania infections in humans....

  17. No Evidence of Increase in Calcitonin Concentrations or Development of C-Cell Malignancy in Response to Liraglutide for Up to 5 Years in the LEADER Trial

    DEFF Research Database (Denmark)

    Hegedüs, Laszlo; Sherman, Steven I; Tuttle, R Michael

    2018-01-01

    of increase in calcitonin concentrations in male (estimated treatment ratio [ETR] 1.03 [95% CI 1.00, 1.06]; P = 0.068) and female (ETR 1.00 [95% CI 0.97, 1.02]; P = 0.671) subgroups. There were no episodes of C-cell hyperplasia or medullary thyroid carcinoma in liraglutide-treated patients. CONCLUSIONS...

  18. Two rice GRAS family genes responsive to N -acetylchitooligosaccharide elicitor are induced by phytoactive gibberellins: evidence for cross-talk between elicitor and gibberellin signaling in rice cells.

    Science.gov (United States)

    Day, R Bradley; Tanabe, Shigeru; Koshioka, Masaji; Mitsui, Toshiaki; Itoh, Hironori; Ueguchi-Tanaka, Miyako; Matsuoka, Makoto; Kaku, Hanae; Shibuya, Naoto; Minami, Eiichi

    2004-01-01

    In this study, we present data showing that two members of the GRAS family of genes from rice, CIGR1 and CIGR2 (chitin-inducible gibberellin-responsive), inducible by the potent elicitor N -acetylchitooligosaccharide (GN), are rapidly induced by exogenous gibberellins. The pattern of mRNA accumulation was dependent on the dose and biological activity of the gibberellins, suggesting that the induction of the genes by gibberellin is mediated by a biological receptor capable of specific recognition and signal transduction upon perception of the phytoactive compounds. Further pharmacological analysis revealed that the CIGR1 and CIGR2 mRNA accumulation by treatment with gibberellin is dependent upon protein phosphorylation/dephosphorylation events. In rice calli derived from slender rice 1, a constitutive gibberellin-responsive mutant, or d1, a mutant deficient in the alpha -subunit of the heterotrimeric G-protein, CIGR1 and CIGR2 were induced by a GN elicitor, yet not by gibberellin. Neither gibberellin nor GN showed related activities in defense or development, respectively. These results strongly suggested that the signal transduction cascade from gibberellin is independent of that from GN, and further implied that CIGR1 and CIGR2 have dual, distinct roles in defense and development.

  19. Frequency response of electrochemical cells

    Science.gov (United States)

    Thomas, Daniel L.

    1990-01-01

    The main objective was to examine the feasibility of using frequency response techniques (1) as a tool in destructive physical analysis of batteries, particularly for estimating electrode structural parameters such as specific area, porosity, and tortuosity and (2) as a non-destructive testing technique for obtaining information such as state of charge and acceptability for space flight. The phenomena that contribute to the frequency response of an electrode include: (1) double layer capacitance; (2) Faradaic reaction resistance; (3) mass transfer of Warburg impedance; and (4) ohmic solution resistance. Nickel cadmium cells were investigated in solutions of KOH. A significant amount of data was acquired. Quantitative data analysis, using the developed software, is planned for the future.

  20. Epidermal Growth Factor Receptor Mutation (EGFR) Testing for Prediction of Response to EGFR-Targeting Tyrosine Kinase Inhibitor (TKI) Drugs in Patients with Advanced Non-Small-Cell Lung Cancer: An Evidence-Based Analysis.

    Science.gov (United States)

    2010-01-01

    In February 2010, the Medical Advisory Secretariat (MAS) began work on evidence-based reviews of the literature surrounding three pharmacogenomic tests. This project came about when Cancer Care Ontario (CCO) asked MAS to provide evidence-based analyses on the effectiveness and cost-effectiveness of three oncology pharmacogenomic tests currently in use in Ontario.Evidence-based analyses have been prepared for each of these technologies. These have been completed in conjunction with internal and external stakeholders, including a Provincial Expert Panel on Pharmacogenetics (PEPP). Within the PEPP, subgroup committees were developed for each disease area. For each technology, an economic analysis was also completed by the Toronto Health Economics and Technology Assessment Collaborative (THETA) and is summarized within the reports.THE FOLLOWING REPORTS CAN BE PUBLICLY ACCESSED AT THE MAS WEBSITE AT: http://www.health.gov.on.ca/mas or at www.health.gov.on.ca/english/providers/program/mas/mas_about.htmlGENE EXPRESSION PROFILING FOR GUIDING ADJUVANT CHEMOTHERAPY DECISIONS IN WOMEN WITH EARLY BREAST CANCER: An Evidence-Based AnalysisEpidermal Growth Factor Receptor Mutation (EGFR) Testing for Prediction of Response to EGFR-Targeting Tyrosine Kinase Inhibitor (TKI) Drugs in Patients with Advanced Non-Small-Cell Lung Cancer: an Evidence-Based AnalysisK-RAS testing in Treatment Decisions for Advanced Colorectal Cancer: an Evidence-Based Analysis The Medical Advisory Secretariat undertook a systematic review of the evidence on the clinical effectiveness and cost-effectiveness of epidermal growth factor receptor (EGFR) mutation testing compared with no EGFR mutation testing to predict response to tyrosine kinase inhibitors (TKIs), gefitinib (Iressa(®)) or erlotinib (Tarceva(®)) in patients with advanced non-small cell lung cancer (NSCLC). TARGET POPULATION AND CONDITION With an estimated 7,800 new cases and 7,000 deaths last year, lung cancer is the leading cause of cancer

  1. Emerging Evidence for Platelets as Immune and Inflammatory Effector Cells

    Directory of Open Access Journals (Sweden)

    Matthew Thomas Rondina

    2014-12-01

    Full Text Available While traditionally recognized for their roles in hemostatic pathways, emerging evidence demonstrates that platelets have previously unrecognized, dynamic roles that span the immune continuum. These newly-recognized platelet functions, including the secretion of immune mediators, interactions with endothelial cells, monocytes, and neutrophils, toll-like receptor (TLR mediated responses, and induction of neutrophil extracellular trap (NET formation, bridge thrombotic and inflammatory pathways and contribute to host defense mechanisms against invading pathogens. In this focused review, we highlight several of these emerging aspects of platelet biology and their implications in clinical infectious syndromes.

  2. Human regulatory B cells control the TFH cell response.

    Science.gov (United States)

    Achour, Achouak; Simon, Quentin; Mohr, Audrey; Séité, Jean-François; Youinou, Pierre; Bendaoud, Boutahar; Ghedira, Ibtissem; Pers, Jacques-Olivier; Jamin, Christophe

    2017-07-01

    Follicular helper T (T FH ) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of T FH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on T FH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate T FH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing T FH cell maturation. In cocultures they differentiated B cells into CD138 + plasma and IgD - CD27 + memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented T FH cell development. Added to T FH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3 + CXCR5 + PD-1 + follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on T FH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Human Breg cells control T FH cell maturation, expand follicular regulatory T cells, and inhibit the T FH cell-mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the T FH cell-dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  3. Temporal Analyses of the Response of Intervertebral Disc Cells and Mesenchymal Stem Cells to Nutrient Deprivation

    Directory of Open Access Journals (Sweden)

    Sarah A. Turner

    2016-01-01

    Full Text Available Much emphasis has been placed recently on the repair of degenerate discs using implanted cells, such as disc cells or bone marrow derived mesenchymal stem cells (MSCs. This study examines the temporal response of bovine and human nucleus pulposus (NP cells and MSCs cultured in monolayer following exposure to altered levels of glucose (0, 3.15, and 4.5 g/L and foetal bovine serum (0, 10, and 20% using an automated time-lapse imaging system. NP cells were also exposed to the cell death inducers, hydrogen peroxide and staurosporine, in comparison to serum starvation. We have demonstrated that human NP cells show an initial “shock” response to reduced nutrition (glucose. However, as time progresses, NP cells supplemented with serum recover with minimal evidence of cell death. Human NP cells show no evidence of proliferation in response to nutrient supplementation, whereas MSCs showed greater response to increased nutrition. When specifically inducing NP cell death with hydrogen peroxide and staurosporine, as expected, the cell number declined. These results support the concept that implanted NP cells or MSCs may be capable of survival in the nutrient-poor environment of the degenerate human disc, which has important clinical implications for the development of IVD cell therapies.

  4. Regulation of T cell responses in atherosclerosis

    NARCIS (Netherlands)

    Puijvelde, Gijsbrecht Henricus Maria van

    2007-01-01

    One of the most important characteristics of atherosclerosis is the chronic inflammatory response in which T cells and NKT cells are very important. In this thesis several methods to modulate the activity of these T and NKT cells in atherosclerosis are described. The induction of regulatory T cells

  5. Cell Culture Assay for Human Noroviruses [response

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Tim M.; Honer Zu Bentrup, Kerstin; Orosz Coghlan, Patricia; Dohnalkova, Alice; Mayer, Brooke K.; Bartholomew, Rachel A.; Valdez, Catherine O.; Bruckner-Lea, Cindy J.; Gerba, Charles P.; Abbaszadegan, Morteza A.; Nickerson, Cheryl A.

    2007-07-01

    We appreciate the comments provided by Leung et al., in response to our recently published article “In Vitro Cell Culture Infectivity Assay for Human Noroviruses” by Straub et al. (1). The specific aim of our project was to develop an in vitro cell culture infectivity assay for human noroviruses (hNoV) to enhance risk assessments when they are detected in water supplies. Reverse transcription (RT) qualitative or quantitative PCR are the primary assays for waterborne NoV monitoring. However, these assays cannot distinguish between infectious vs. non-infectious virions. When hNoV is detected in water supplies, information provided by our infectivity assay will significantly improve risk assessment models and protect human health, regardless of whether we are propagating NoV. Indeed, in vitro cell culture infectivity assays for the waterborne pathogen Cryptosporidium parvum that supplement approved fluorescent microscopy assays, do not result in amplification of the environmentally resistant hard-walled oocysts (2). However, identification of life cycle stages in cell culture provides evidence of infectious oocysts in a water supply. Nonetheless, Leung et al.’s assertion regarding the suitability of our method for the in vitro propagation of high titers of NoV is valid for the medical research community. In this case, well-characterized challenge pools of virus would be useful for developing and testing diagnostics, therapeutics, and vaccines. As further validation of our published findings, we have now optimized RT quantitative PCR to assess the level of viral production in cell culture, where we are indeed finding significant increases in viral titer. The magnitude and time course of these increases is dependent on both virus strain and multiplicity of infection. We are currently preparing a manuscript that will discuss these findings in greater detail, and the implications this may have for creating viral challenge pools

  6. Evidence for a Role for the Plasma Membrane in the Nanomechanical Properties of the Cell Wall as Revealed by an Atomic Force Microscopy Study of the Response of Saccharomyces cerevisiae to Ethanol Stress.

    Science.gov (United States)

    Schiavone, Marion; Formosa-Dague, Cécile; Elsztein, Carolina; Teste, Marie-Ange; Martin-Yken, Helene; De Morais, Marcos A; Dague, Etienne; François, Jean M

    2016-08-01

    A wealth of biochemical and molecular data have been reported regarding ethanol toxicity in the yeast Saccharomyces cerevisiae However, direct physical data on the effects of ethanol stress on yeast cells are almost nonexistent. This lack of information can now be addressed by using atomic force microscopy (AFM) technology. In this report, we show that the stiffness of glucose-grown yeast cells challenged with 9% (vol/vol) ethanol for 5 h was dramatically reduced, as shown by a 5-fold drop of Young's modulus. Quite unexpectedly, a mutant deficient in the Msn2/Msn4 transcription factor, which is known to mediate the ethanol stress response, exhibited a low level of stiffness similar to that of ethanol-treated wild-type cells. Reciprocally, the stiffness of yeast cells overexpressing MSN2 was about 35% higher than that of the wild type but was nevertheless reduced 3- to 4-fold upon exposure to ethanol. Based on these and other data presented herein, we postulated that the effect of ethanol on cell stiffness may not be mediated through Msn2/Msn4, even though this transcription factor appears to be a determinant in the nanomechanical properties of the cell wall. On the other hand, we found that as with ethanol, the treatment of yeast with the antifungal amphotericin B caused a significant reduction of cell wall stiffness. Since both this drug and ethanol are known to alter, albeit by different means, the fluidity and structure of the plasma membrane, these data led to the proposition that the cell membrane contributes to the biophysical properties of yeast cells. Ethanol is the main product of yeast fermentation but is also a toxic compound for this process. Understanding the mechanism of this toxicity is of great importance for industrial applications. While most research has focused on genomic studies of ethanol tolerance, we investigated the effects of ethanol at the biophysical level and found that ethanol causes a strong reduction of the cell wall rigidity (or

  7. Evidence for a Role for the Plasma Membrane in the Nanomechanical Properties of the Cell Wall as Revealed by an Atomic Force Microscopy Study of the Response of Saccharomyces cerevisiae to Ethanol Stress

    Science.gov (United States)

    Schiavone, Marion; Formosa-Dague, Cécile; Elsztein, Carolina; Teste, Marie-Ange; Martin-Yken, Helene; De Morais, Marcos A.; Dague, Etienne

    2016-01-01

    ABSTRACT A wealth of biochemical and molecular data have been reported regarding ethanol toxicity in the yeast Saccharomyces cerevisiae. However, direct physical data on the effects of ethanol stress on yeast cells are almost nonexistent. This lack of information can now be addressed by using atomic force microscopy (AFM) technology. In this report, we show that the stiffness of glucose-grown yeast cells challenged with 9% (vol/vol) ethanol for 5 h was dramatically reduced, as shown by a 5-fold drop of Young's modulus. Quite unexpectedly, a mutant deficient in the Msn2/Msn4 transcription factor, which is known to mediate the ethanol stress response, exhibited a low level of stiffness similar to that of ethanol-treated wild-type cells. Reciprocally, the stiffness of yeast cells overexpressing MSN2 was about 35% higher than that of the wild type but was nevertheless reduced 3- to 4-fold upon exposure to ethanol. Based on these and other data presented herein, we postulated that the effect of ethanol on cell stiffness may not be mediated through Msn2/Msn4, even though this transcription factor appears to be a determinant in the nanomechanical properties of the cell wall. On the other hand, we found that as with ethanol, the treatment of yeast with the antifungal amphotericin B caused a significant reduction of cell wall stiffness. Since both this drug and ethanol are known to alter, albeit by different means, the fluidity and structure of the plasma membrane, these data led to the proposition that the cell membrane contributes to the biophysical properties of yeast cells. IMPORTANCE Ethanol is the main product of yeast fermentation but is also a toxic compound for this process. Understanding the mechanism of this toxicity is of great importance for industrial applications. While most research has focused on genomic studies of ethanol tolerance, we investigated the effects of ethanol at the biophysical level and found that ethanol causes a strong reduction of the cell

  8. Dynamics of NKT-Cell Responses to Chlamydial Infection.

    Science.gov (United States)

    Shekhar, Sudhanshu; Joyee, Antony George; Yang, Xi

    2015-01-01

    Natural killer T (NKT) cells have gained great attention owing to their critical functional roles in immunity to various pathogens. In this review, we provide an overview of the current knowledge on the role of NKT cells in host defense against and pathogenesis due to Chlamydia, which is an intracellular bacterial pathogen that poses a threat to the public health worldwide. Accumulating evidence has demonstrated that NKT cells, particularly invariant NKT (iNKT) cells, play a crucial role in host defense against chlamydial infections, especially in C. pneumoniae infection. iNKT cells can promote type-1 protective responses to C. pneumoniae by inducing enhanced production of IL-12 by dendritic cells (DCs), in particular CD8α+ DCs, which promote the differentiation of naive T cells into protective IFN-γ-producing Th1/Tc1 type CD4+/CD8+ T cells. This iNKT-cell-mediated modulation of DC function is largely dependent upon CD40-CD40L interaction, IFN-γ production, and cell-to-cell contact. In addition, iNKT cells modulate the function of natural killer cells. NKT cells may be also involved in the pathogenesis of some chlamydial diseases by inducing different patterns of cytokine production. A better understanding of NKT-cell biology will enable us to rationally design prophylactic and therapeutic tools to combat infectious diseases.

  9. Mast cells are important modifiers of autoimmune disease: With so much evidence, why is there controversy?

    Directory of Open Access Journals (Sweden)

    Melissa Ann Brown

    2012-06-01

    Full Text Available There is abundant evidence that mast cells are active participants in events that mediate tissue damage in autoimmune disease. Disease-associated increases in mast cell numbers accompanied by mast cell degranulation and elaboration of numerous mast cell mediators at sites of inflammation are commonly observed in many human autoimmune diseases including multiple sclerosis, rheumatoid arthritis and bullous pemphigoid. In animal models, treatment with mast cell stabilizing drugs or mast cell ablation can result in diminished disease. A variety of receptors including those engaged by antibody, complement, pathogens and intrinsic danger signals are implicated in mast cell activation in disease. Similar to their role as first responders in infection settings, mast cells likely orchestrate early recruitment of immune cells, including neutrophils, to the sites of autoimmune destruction. This co-localization promotes cellular crosstalk and activation and results in the amplification of the local inflammatory response thereby promoting and sustaining tissue damage. Despite the evidence, there is still a debate regarding the relative role of mast cells in these processes. However, by definition, mast cells can only act as accessory cells to the self-reactive T and/or antibody driven autoimmune responses. Thus, when evaluating mast cell involvement using existing and somewhat imperfect animal models of disease, their importance is sometimes obscured. However, these potent immune cells are undoubtedly major contributors to autoimmunity and should be considered as important targets for therapeutic disease intervention.

  10. Demand Response in U.S. Electricity Markets: Empirical Evidence

    OpenAIRE

    Cappers, Peter

    2009-01-01

    Empirical evidence concerning demand response (DR) resources is needed in order to establish baseline conditions, develop standardized methods to assess DR availability and performance, and to build confidence among policymakers, utilities, system operators, and stakeholders that DR resources do offer a viable, cost-effective alternative to supply-side investments. This paper summarizes the existing contribution of DR resources in U.S. electric power markets. In 2008, customers enrolled in ...

  11. Responses of Cells to Flow in Vitro

    Directory of Open Access Journals (Sweden)

    Shigehiro Hashimoto

    2013-06-01

    Full Text Available The response of cells to a flow has been studied in vitro. The response of cells was examined in two types of flow channels: a circumnutating flow in a donut-shaped open channel in a culture dish, and a one-way flow in a parallelepiped rhombus flow channel. Variation was made on the material of the parallelepiped channel to study on adhesion of cells to the plates: glass and polydimethylsiloxane. Behavior of cells on the plate was observed under a flow of a medium with an inverted phase-contrast-microscope. The shear stress on the plate is calculated with an estimated parabolic distribution of the velocity between the parallel plates. The adhesion of cells was evaluated with the cumulated shear, which is a product of the shear stress and the exposure time. The experimental results show that cells are responsive to the flow, which governs orientation, exfoliation, and differentiation. The response depends on the kinds of cells: endothelial cells orient along the stream line, although myocytes orient perpendicular to the stream line. The adhesion depends on the combination between scaffold and cell: myocytes are more adhesive to glass than cartilage cells, and fibroblasts are more adhesive to oxygenated polydimethylsiloxane than glass.

  12. Collective cell migration during inflammatory response

    Science.gov (United States)

    Wu, Di; Stroka, Kimberly; Aranda-Espinoza, Helim

    2012-02-01

    Wound scratch healing assays of endothelial cell monolayers is a simple model to study collective cell migration as a function of biological signals. A signal of particular interest is the immune response, which after initial wounding in vivo causes the release of various inflammatory factors such as tumor necrosis alpha (TNF-α). TNF-α is an innate inflammatory cytokine that can induce cell growth, cell necrosis, and change cell morphology. We studied the effects of TNF-α on collective cell migration using the wound healing assays and measured several migration metrics, such as rate of scratch closure, velocities of leading edge and bulk cells, closure index, and velocity correlation functions between migrating cells. We observed that TNF-α alters all migratory metrics as a function of the size of the scratch and TNF-α content. The changes observed in migration correlate with actin reorganization upon TNF-α exposure.

  13. Evidence for tension-based regulation of Drosophila MAL and SRF during invasive cell migration.

    Science.gov (United States)

    Somogyi, Kálmán; Rørth, Pernille

    2004-07-01

    Cells migrating through a tissue exert force via their cytoskeleton and are themselves subject to tension, but the effects of physical forces on cell behavior in vivo are poorly understood. Border cell migration during Drosophila oogenesis is a useful model for invasive cell movement. We report that this migration requires the activity of the transcriptional factor serum response factor (SRF) and its cofactor MAL-D and present evidence that nuclear accumulation of MAL-D is induced by cell stretching. Border cells that cannot migrate lack nuclear MAL-D but can accumulate it if they are pulled by other migrating cells. Like mammalian MAL, MAL-D also responds to activated Diaphanous, which affects actin dynamics. MAL-D/SRF activity is required to build a robust actin cytoskeleton in the migrating cells; mutant cells break apart when initiating migration. Thus, tension-induced MAL-D activity may provide a feedback mechanism for enhancing cytoskeletal strength during invasive migration.

  14. Metabolomic Responses of Guard Cells and Mesophyll Cells to Bicarbonate

    Science.gov (United States)

    Misra, Biswapriya B.; de Armas, Evaldo; Tong, Zhaohui; Chen, Sixue

    2015-01-01

    Anthropogenic CO2 presently at 400 ppm is expected to reach 550 ppm in 2050, an increment expected to affect plant growth and productivity. Paired stomatal guard cells (GCs) are the gate-way for water, CO2, and pathogen, while mesophyll cells (MCs) represent the bulk cell-type of green leaves mainly for photosynthesis. We used the two different cell types, i.e., GCs and MCs from canola (Brassica napus) to profile metabolomic changes upon increased CO2 through supplementation with bicarbonate (HCO3 -). Two metabolomics platforms enabled quantification of 268 metabolites in a time-course study to reveal short-term responses. The HCO3 - responsive metabolomes of the cell types differed in their responsiveness. The MCs demonstrated increased amino acids, phenylpropanoids, redox metabolites, auxins and cytokinins, all of which were decreased in GCs in response to HCO3 -. In addition, the GCs showed differential increases of primary C-metabolites, N-metabolites (e.g., purines and amino acids), and defense-responsive pathways (e.g., alkaloids, phenolics, and flavonoids) as compared to the MCs, indicating differential C/N homeostasis in the cell-types. The metabolomics results provide insights into plant responses and crop productivity under future climatic changes where elevated CO2 conditions are to take center-stage. PMID:26641455

  15. Public responses to water reuse - Understanding the evidence.

    Science.gov (United States)

    Smith, H M; Brouwer, S; Jeffrey, P; Frijns, J

    2018-02-01

    Over the years, much research has attempted to unpack what drives public responses to water reuse, using a variety of approaches. A large amount of this work was captured by an initial review that covered research undertaken up to the early 2000s (Hartley, 2006). This paper showcases post-millennium evidence and thinking around public responses to water reuse, and highlights the novel insights and shifts in emphasis that have occurred in the field. Our analysis is structured around four broad, and highly interrelated, strands of thinking: 1) work focused on identifying the range of factors that influence public reactions to the concept of water reuse, and broadly looking for associations between different factors; 2) more specific approaches rooted in the socio-psychological modelling techniques; 3) work with a particular focus on understanding the influences of trust, risk perceptions and affective (emotional) reactions; and 4) work utilising social constructivist perspectives and socio-technical systems theory to frame responses to water reuse. Some of the most significant advancements in thinking in this field stem from the increasingly sophisticated understanding of the 'yuck factor' and the role of such pre-cognitive affective reactions. These are deeply entrenched within individuals, but are also linked with wider societal processes and social representations. Work in this area suggests that responses to reuse are situated within an overall process of technological 'legitimation'. These emerging insights should help stimulate some novel thinking around approaches to public engagement for water reuse. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Evidence-Responsiveness and the Ongoing Autonomy of Treatment Preferences.

    Science.gov (United States)

    Weimer, Steven

    2017-06-14

    To be an autonomous agent is to determine one's own path in life. However, this cannot plausibly be seen as a one-off affair. An autonomous agent does not merely set herself on a particular course and then lock the steering wheel in place, so to speak, but must maintain some form of ongoing control over her direction in life-must keep her eyes on the road and her hands on the wheel. Circumstances often change in important and unexpected ways, after all, and it is reasonable to think that a crucial part of autonomy consists of the ability and disposition to recognize and properly respond to such changes. This implies, I contend, that a patient whose initial decision to undergo a given treatment satisfied plausible requirements of autonomy, but who is now unable to recognize that available evidence indicates the need to reconsider her medical situation and options has come to lack autonomy with respect to her desire to continue that treatment. However, and despite its importance with respect to both theoretical understandings of autonomy and applications of the concept to clinical ethics, this ongoing aspect of autonomy has received little attention. This paper aims to go some way toward remedying that. I first critically review two of the few theories of autonomy that do address "evidence-responsiveness" so as to identify and elaborate what I take to be the most promising way in which to account for this aspect of autonomy. After considering and responding to a possible objection to the evidence-responsiveness condition I propose, I conclude by discussing its clinical implications. That condition, I argue, is not merely theoretically sound, but can and should be applied to clinical practice.

  17. Evidence for differentiation of cell wall poles in Bacillus subtilis

    International Nuclear Information System (INIS)

    Sonnenfeld, E.M.

    1985-01-01

    Previous data have suggested that the chromosome of Bacillus subtilis was found to the cell surface at polar regions. A significant corollary of DNA attachment to cell poles is the role of the cell wall in chromosome segregation. This project was mainly concerned with visualizing the DNA-cell wall association through autoradiography. The origin and terminus of replication were labelled with ( 3 H)-thymidine using a temperature-sensitive DNA initiation mutant. It was found that most of the radioactivity was associated with cell poles. Ultrastructural analyses of cell walls stained with dilute cationized ferritin showed that the polar area contained a site of dense electronegativity. It is not immediately apparent why cell wall poles would contain an area with a high concentration of negative charge. This finding may be related to the cell pole functioning as the site of chromosome attachment. An additional observation encountered in this study was that cell wall exhibited asymmetry with regard to negative charge, the outside surface being more electronegative than the inside. A significant consequence of this finding is that both teichoic acid and muramyl peptides are situated perpendicularly to the cell surface. This favored arrangement may facilitate cell separation during the division process due to opposition of like charges at septa. The results of this work provide further convincing evidence that the cell wall of B. subtilis is differentiated

  18. T-cell responses in malaria

    DEFF Research Database (Denmark)

    Hviid, L; Jakobsen, P H; Abu-Zeid, Y A

    1992-01-01

    Malaria is caused by infection with protozoan parasites of the genus Plasmodium. It remains one of the most severe health problems in tropical regions of the world, and the rapid spread of resistance to drugs and insecticides has stimulated intensive research aimed at the development of a malaria...... vaccine. Despite this, no efficient operative vaccine is currently available. A large amount of information on T-cell responses to malaria antigens has been accumulated, concerning antigens derived from all stages of the parasite life cycle. The present review summarizes some of that information......, and discusses factors affecting the responses of T cells to malaria antigens....

  19. T-cell proliferative responses following sepsis in neonatal rats.

    Science.gov (United States)

    Dallal, Ousama; Ravindranath, Thyyar M; Choudhry, Mashkoor A; Kohn, Annamarie; Muraskas, Jonathan K; Namak, Shahla Y; Alattar, Mohammad H; Sayeed, Mohammed M

    2003-01-01

    Both experimental and clinical evidence suggest a suppression of T-cell function in burn and sepsis. The objective of the present study was to evaluate splenocyte and purified T-cell proliferative response and IL-2 production in septic neonatal rats. We also examined if alterations in T-cell proliferation and IL-2 production in neonatal sepsis is due to elevation in PGE2. PGE2 is known to play a significant role in T-cell suppression during sepsis in adults. Sepsis was induced in 15-day-old neonatal Sprague-Dawley rats by implanting 0.1 cm3 of fecal pellet impregnated with Escherichia coli (50 CFU) and Bacteroides fragilis (10(3) CFU). Animals receiving fecal pellets without the bacteria were designated as sterile. A group of septic and sterile rats were treated with PGE2 synthesis inhibitors, NS398 and resveratrol. These treatments of animals allowed us to evaluate the role of PGE2 in T-cell suppression during neonatal sepsis. Splenocytes as well as purified T cells were prepared and then proliferative response and IL-2 productive capacities were measured. A significant suppression of splenocyte proliferation and IL-2 production was noticed in both sterile and septic animals compared to the T cells from unoperated control rats. In contrast, the proliferation and IL-2 production by nylon wool purified T cells in sterile rats was not significantly different from control rats, whereas, a significant suppression in Con A-mediated T-cell proliferation and IL-2 production noticed in septic rat T cells compared to the sterile and control rat T cells. Such decrease in T-cell proliferation and IL-2 production was accompanied with 20-25% deaths in neonates implanted with septic pellets. No mortality was noted in sterile-implanted neonates. Treatment of animals with COX-1 inhibitor had no effect on T-cell proliferation response in both septic and sterile groups, whereas COX-2 inhibitor abrogated the decrease in T-cell proliferative response in the septic group. The treatment

  20. Atypical radiation response of SCID cells

    Science.gov (United States)

    Chawapun, Nisa

    Murine SCID (severe combined immune deficiency) cells are well known for their defect in DNA double-strand break repair and in variable(diversity)joining [V(D)J] recombination due to a mutation in a catalytic subunit of DNA-dependent protein kinase (DNA-PKcs). As a consequence, scid cells are hypersensitive to ionizing radiation. The present study showed that asynchronous populations of scid cells were about two-fold more sensitive than Balb/c with respect to cell killing and the defect in scid cells was corrected by complementation with human chromosome 8. Analysis of the survival of synchronized populations as a function of the cell cycle revealed that while scid cells were hypersensitive in all cell cycle phases compared to wild-type cells, this hypersensitivity is even more pronounced in G1 phase. The hypersensitivity reduced as the cells progressed into S phase suggested that homologous recombination repair plays a role. The results imply that there are at least two pathways for the repair of DSB DNA, consistent with a model previously proposed by others. The scid cells were also more sensitive to UVC light (254 nm) killing as compared to wild type cells by clonogenic survival. Using a host cell reactivation (HCR) assay to study the nucleotide excision repair (NER) which is the major repair pathway for UV-photoproducts, the results showed that NER in scid cells was not as efficient as CB- 17. This suggests that DNA-PK is involved in NER as well as non-homologous end-joining (NHEJ) DSB repair which is responsible for ionizing radiation sensitivity in scid cells. Repair in scid cells was not totally absent as shown by low dose rate sparing of cell killing after exposure to 137Cs γ-rays at dose rate of 0.6 cGy/h, 1.36 cGy/h, 6 cGy/h as compared to high dose rate at 171 cGy/min, although this phenomenon could be explained partly by proliferation. However, for radiation induced transformation, no significant dose rate effect was seen. A plot of transformation

  1. Demand response in U.S. electricity markets: Empirical evidence

    International Nuclear Information System (INIS)

    Cappers, Peter; Goldman, Charles; Kathan, David

    2010-01-01

    Empirical evidence concerning demand response (DR) resources is needed in order to establish baseline conditions, develop standardized methods to assess DR availability and performance, and to build confidence among policymakers, utilities, system operators, and stakeholders that DR resources do offer a viable, cost-effective alternative to supply-side investments. This paper summarizes the existing contribution of DR resources in U.S. electric power markets. In 2008, customers enrolled in existing wholesale and retail DR programs were capable of providing ∝38,000 MW of potential peak load reductions in the United States. Participants in organized wholesale market DR programs, though, have historically overestimated their likely performance during declared curtailments events, but appear to be getting better as they and their agents gain experience. In places with less developed organized wholesale market DR programs, utilities are learning how to create more flexible DR resources by adapting legacy load management programs to fit into existing wholesale market constructs. Overall, the development of open and organized wholesale markets coupled with direct policy support by the Federal Energy Regulatory Commission has facilitated new entry by curtailment service providers, which has likely expanded the demand response industry and led to product and service innovation. (author)

  2. The Role of the Immune Response in Merkel Cell Carcinoma

    International Nuclear Information System (INIS)

    Triozzi, Pierre L.; Fernandez, Anthony P.

    2013-01-01

    Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer. The Merkel cell polyomavirus (MCPyV) is implicated in its pathogenesis. Immune mechanisms are also implicated. Patients who are immunosuppressed have an increased risk. There is evidence that high intratumoral T-cell counts and immune transcripts are associated with favorable survival. Spontaneous regressions implicate immune effector mechanisms. Immunogenicity is also supported by observation of autoimmune paraneoplastic syndromes. Case reports suggest that immune modulation, including reduction of immune suppression, can result in tumor regression. The relationships between MCPyV infection, the immune response, and clinical outcome, however, remain poorly understood. Circulating antibodies against MCPyV antigens are present in most individuals. MCPyV-reactive T cells have been detected in both MCC patients and control subjects. High intratumoral T-cell counts are also associated with favorable survival in MCPyV-negative MCC. That the immune system plays a central role in preventing and controlling MCC is supported by several observations. MCCs often develop, however, despite the presence of humoral and cellular immune responses. A better understanding on how MCPyV and MCC evade the immune response will be necessary to develop effective immunotherapies

  3. The Role of the Immune Response in Merkel Cell Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Triozzi, Pierre L., E-mail: triozzp@ccf.org [Taussig Cancer Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Fernandez, Anthony P. [Departments of Dermatology and Anatomic Pathology, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195 (United States)

    2013-02-28

    Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer. The Merkel cell polyomavirus (MCPyV) is implicated in its pathogenesis. Immune mechanisms are also implicated. Patients who are immunosuppressed have an increased risk. There is evidence that high intratumoral T-cell counts and immune transcripts are associated with favorable survival. Spontaneous regressions implicate immune effector mechanisms. Immunogenicity is also supported by observation of autoimmune paraneoplastic syndromes. Case reports suggest that immune modulation, including reduction of immune suppression, can result in tumor regression. The relationships between MCPyV infection, the immune response, and clinical outcome, however, remain poorly understood. Circulating antibodies against MCPyV antigens are present in most individuals. MCPyV-reactive T cells have been detected in both MCC patients and control subjects. High intratumoral T-cell counts are also associated with favorable survival in MCPyV-negative MCC. That the immune system plays a central role in preventing and controlling MCC is supported by several observations. MCCs often develop, however, despite the presence of humoral and cellular immune responses. A better understanding on how MCPyV and MCC evade the immune response will be necessary to develop effective immunotherapies.

  4. FMRI evidence of 'mirror' responses to geometric shapes.

    Directory of Open Access Journals (Sweden)

    Clare Press

    Full Text Available Mirror neurons may be a genetic adaptation for social interaction. Alternatively, the associative hypothesis proposes that the development of mirror neurons is driven by sensorimotor learning, and that, given suitable experience, mirror neurons will respond to any stimulus. This hypothesis was tested using fMRI adaptation to index populations of cells with mirror properties. After sensorimotor training, where geometric shapes were paired with hand actions, BOLD response was measured while human participants experienced runs of events in which shape observation alternated with action execution or observation. Adaptation from shapes to action execution, and critically, observation, occurred in ventral premotor cortex (PMv and inferior parietal lobule (IPL. Adaptation from shapes to execution indicates that neuronal populations responding to the shapes had motor properties, while adaptation to observation demonstrates that these populations had mirror properties. These results indicate that sensorimotor training induced populations of cells with mirror properties in PMv and IPL to respond to the observation of arbitrary shapes. They suggest that the mirror system has not been shaped by evolution to respond in a mirror fashion to biological actions; instead, its development is mediated by stimulus-general processes of learning within a system adapted for visuomotor control.

  5. FMRI evidence of 'mirror' responses to geometric shapes.

    Science.gov (United States)

    Press, Clare; Catmur, Caroline; Cook, Richard; Widmann, Hannah; Heyes, Cecilia; Bird, Geoffrey

    2012-01-01

    Mirror neurons may be a genetic adaptation for social interaction. Alternatively, the associative hypothesis proposes that the development of mirror neurons is driven by sensorimotor learning, and that, given suitable experience, mirror neurons will respond to any stimulus. This hypothesis was tested using fMRI adaptation to index populations of cells with mirror properties. After sensorimotor training, where geometric shapes were paired with hand actions, BOLD response was measured while human participants experienced runs of events in which shape observation alternated with action execution or observation. Adaptation from shapes to action execution, and critically, observation, occurred in ventral premotor cortex (PMv) and inferior parietal lobule (IPL). Adaptation from shapes to execution indicates that neuronal populations responding to the shapes had motor properties, while adaptation to observation demonstrates that these populations had mirror properties. These results indicate that sensorimotor training induced populations of cells with mirror properties in PMv and IPL to respond to the observation of arbitrary shapes. They suggest that the mirror system has not been shaped by evolution to respond in a mirror fashion to biological actions; instead, its development is mediated by stimulus-general processes of learning within a system adapted for visuomotor control.

  6. Evidence for an early innate immune response in the motor cortex of ALS.

    Science.gov (United States)

    Jara, Javier H; Genç, Barış; Stanford, Macdonell J; Pytel, Peter; Roos, Raymond P; Weintraub, Sandra; Mesulam, M Marsel; Bigio, Eileen H; Miller, Richard J; Özdinler, P Hande

    2017-06-26

    Recent evidence indicates the importance of innate immunity and neuroinflammation with microgliosis in amyotrophic lateral sclerosis (ALS) pathology. The MCP1 (monocyte chemoattractant protein-1) and CCR2 (CC chemokine receptor 2) signaling system has been strongly associated with the innate immune responses observed in ALS patients, but the motor cortex has not been studied in detail. After revealing the presence of MCP1 and CCR2 in the motor cortex of ALS patients, to elucidate, visualize, and define the timing, location and the extent of immune response in relation to upper motor neuron vulnerability and progressive degeneration in ALS, we developed MCP1-CCR2-hSOD1 G93A mice, an ALS reporter line, in which cells expressing MCP1 and CCR2 are genetically labeled by monomeric red fluorescent protein-1 and enhanced green fluorescent protein, respectively. In the motor cortex of MCP1-CCR2-hSOD1 G93A mice, unlike in the spinal cord, there was an early increase in the numbers of MCP1+ cells, which displayed microglial morphology and selectively expressed microglia markers. Even though fewer CCR2+ cells were present throughout the motor cortex, they were mainly infiltrating monocytes. Interestingly, MCP1+ cells were found in close proximity to the apical dendrites and cell bodies of corticospinal motor neurons (CSMN), further implicating the importance of their cellular interaction to neuronal pathology. Similar findings were observed in the motor cortex of ALS patients, where MCP1+ microglia were especially in close proximity to the degenerating apical dendrites of Betz cells. Our findings reveal that the intricate cellular interplay between immune cells and upper motor neurons observed in the motor cortex of ALS mice is indeed recapitulated in ALS patients. We generated and characterized a novel model system, to study the cellular and molecular basis of this close cellular interaction and how that relates to motor neuron vulnerability and progressive degeneration in

  7. Sustained CD8+ T-cell responses induced after acute parvovirus B19 infection in humans

    DEFF Research Database (Denmark)

    Norbeck, Oscar; Isa, Adiba; Pöhlmann, Christoph

    2005-01-01

    Murine models have suggested that CD8+ T-cell responses peak early in acute viral infections and are not sustained, but no evidence for humans has been available. To address this, we longitudinally analyzed the CD8+ T-cell response to human parvovirus B19 in acutely infected individuals. We...... observed striking CD8+ T-cell responses, which were sustained or even increased over many months after the resolution of acute disease, indicating that CD8+ T cells may play a prominent role in the control of parvovirus B19 and other acute viral infections of humans, including potentially those generated...

  8. Evidence for a role of claudin 2 as a proximal tubular stress responsive paracellular water channel

    Energy Technology Data Exchange (ETDEWEB)

    Wilmes, Anja, E-mail: Anja.Wilmes@i-med.ac.at; Aschauer, Lydia; Limonciel, Alice; Pfaller, Walter; Jennings, Paul

    2014-09-01

    Claudins are the major proteins of the tight junctions and the composition of claudin subtypes is decisive for the selective permeability of the paracellular route and thus tissue specific function. Their regulation is complex and subject to interference by several factors, including oxidative stress. Here we show that exposure of cultured human proximal tubule cells (RPTEC/TERT1) to the immunosuppressive drug cyclosporine A (CsA) induces an increase in transepithelial electrical resistance (TEER), a decrease in dome formation (on solid growth supports) and a decrease in water transport (on microporous growth supports). In addition, CsA induced a dramatic decrease in the mRNA for the pore forming claudins -2 and -10, and the main subunits of the Na{sup +}/K{sup +} ATPase. Knock down of claudin 2 by shRNA had no discernable effect on TEER or dome formation but severely attenuated apical to basolateral water reabsorption when cultured on microporous filters. Generation of an osmotic gradient in the basolateral compartment rescued water transport in claudin 2 knock down cells. Inhibition of Na{sup +}/K{sup +} ATPase with ouabain prevented dome formation in both cell types. Taken together these results provide strong evidence that dome formation is primarily due to transcellular water transport following a solute osmotic gradient. However, in RPTEC/TERT1 cells cultured on filters under iso-osmotic conditions, water transport is primarily paracellular, most likely due to local increases in osmolarity in the intercellular space. In conclusion, this study provides strong evidence that claudin 2 is involved in paracellular water transport and that claudin 2 expression is sensitive to compound induced cellular stress. - Highlights: • Cyclosporine A increased TEER and decreased water transport in RPTEC/TERT1 cells. • Claudins 2 and 10 were decreased in response to cyclosporine A. • Knock down of claudin 2 inhibited water transport in proximal tubular cells. • We

  9. Global gene expression response to telomerase in bovine adrenocortical cells

    International Nuclear Information System (INIS)

    Perrault, Steven D.; Hornsby, Peter J.; Betts, Dean H.

    2005-01-01

    The infinite proliferative capability of most immortalized cells is dependent upon the presence of the enzyme telomerase and its ability to maintain telomere length and structure. However, telomerase may be involved in a greater system than telomere length regulation, as recent evidence has shown it capable of increasing wound healing in vivo, and improving cellular proliferation rate and survival from apoptosis in vitro. Here, we describe the global gene expression response to ectopic telomerase expression in an in vitro bovine adrenocortical cell model. Telomerase-immortalized cells showed an increased ability for proliferation and survival in minimal essential medium above cells transgenic for GFP. cDNA microarray analyses revealed an altered cell state indicative of increased adrenocortical cell proliferation regulated by the IGF2 pathway and alterations in members of the TGF-B family. As well, we identified alterations in genes associated with development and wound healing that support a model that high telomerase expression induces a highly adaptable, progenitor-like state

  10. Climate change and biological invasions: evidence, expectations, and response options.

    Science.gov (United States)

    Hulme, Philip E

    2017-08-01

    A changing climate may directly or indirectly influence biological invasions by altering the likelihood of introduction or establishment, as well as modifying the geographic range, environmental impacts, economic costs or management of alien species. A comprehensive assessment of empirical and theoretical evidence identified how each of these processes is likely to be shaped by climate change for alien plants, animals and pathogens in terrestrial, freshwater and marine environments of Great Britain. The strongest contemporary evidence for the potential role of climate change in the establishment of new alien species is for terrestrial arthropods, as a result of their ectothermic physiology, often high dispersal rate and their strong association with trade as well as commensal relationships with human environments. By contrast, there is little empirical support for higher temperatures increasing the rate of alien plant establishment due to the stronger effects of residence time and propagule pressure. The magnitude of any direct climate effect on the number of new alien species will be small relative to human-assisted introductions driven by socioeconomic factors. Casual alien species (sleepers) whose population persistence is limited by climate are expected to exhibit greater rates of establishment under climate change assuming that propagule pressure remains at least at current levels. Surveillance and management targeting sleeper pests and diseases may be the most cost-effective option to reduce future impacts under climate change. Most established alien species will increase their distribution range in Great Britain over the next century. However, such range increases are very likely be the result of natural expansion of populations that have yet to reach equilibrium with their environment, rather than a direct consequence of climate change. To assess the potential realised range of alien species will require a spatially explicit approach that not only

  11. Biomimetic materials for controlling bone cell responses.

    Science.gov (United States)

    Drevelle, Olivier; Faucheux, Nathalie

    2013-01-01

    Bone defects that cannot "heal spontaneously during life" will become an ever greater health problem as populations age. Harvesting autografts has several drawbacks, such as pain and morbidity at both donor and acceptor sites, the limited quantity of material available, and frequently its inappropriate shape. Researchers have therefore developed alternative strategies that involve biomaterials to fill bone defects. These biomaterials must be biocompatible and interact with the surrounding bone tissue to allow their colonization by bone cells and blood vessels. The latest generation biomaterials are not inert; they control cell responses like adhesion, proliferation and differentiation. These biomaterials are called biomimetic materials. This review focuses on the development of third generation materials. We first briefly describe the bone tissue with its cells and matrix, and then how bone cells interact with the extracellular matrix. The next section covers the materials currently used to repair bone defects. Finally, we describe the strategies employed to modify the surface of materials, such as coating with hydroxyapatite and grafting biomolecules.

  12. Regulatory T Cells in Radiotherapeutic Responses

    International Nuclear Information System (INIS)

    Schaue, Dörthe; Xie, Michael W.; Ratikan, Josephine A.; McBride, William H.

    2012-01-01

    Radiation therapy (RT) can extend its influence in cancer therapy beyond what can be attributed to in-field cytotoxicity by modulating the immune system. While complex, these systemic effects can help tip the therapeutic balance in favor of treatment success or failure. Engagement of the immune system is generally through recognition of damage-associated molecules expressed or released as a result of tumor and normal tissue radiation damage. This system has evolved to discriminate pathological from physiological forms of cell death by signaling “danger.” The multiple mechanisms that can be evoked include a shift toward a pro-inflammatory, pro-oxidant microenvironment that can promote maturation of dendritic cells and, in cancer treatment, the development of effector T cell responses to tumor-associated antigens. Control over these processes is exerted by regulatory T cells (Tregs), suppressor macrophages, and immunosuppressive cytokines that act in consort to maintain tolerance to self, limit tissue damage, and re-establish tissue homeostasis. Unfortunately, by the time RT for cancer is initiated the tumor-host relationship has already been sculpted in favor of tumor growth and against immune-mediated mechanisms for tumor regression. Reversing this situation is a major challenge. However, recent data show that removal of Tregs can tip the balance in favor of the generation of radiation-induced anti-tumor immunity. The clinical challenge is to do so without excessive depletion that might precipitate serious autoimmune reactions and increase the likelihood of normal tissue complications. The selective modulation of Treg biology to maintain immune tolerance and control of normal tissue damage, while releasing the “brakes” on anti-tumor immune responses, is a worthy aim with promise for enhancing the therapeutic benefit of RT for cancer.

  13. Regulatory T cells in radiotherapeutic responses

    Directory of Open Access Journals (Sweden)

    Dörthe eSchaue

    2012-08-01

    Full Text Available Radiation therapy (RT can extend its influence in cancer therapy beyond what can be attributed to in-field cytotoxicity by modulating the immune system. While complex, these systemic effects can help tip the therapeutic balance in favor of treatment success or failure. Engagement of the immune system is generally through recognition of damage-associated molecules expressed or released as a result of tumor and normal tissue radiation damage. This system has evolved to discriminate pathological from physiological forms of cell death by signaling danger. The multiple mechanisms that can be evoked include a shift towards a pro-inflammatory, pro-oxidant microenvironment that can promote maturation of dendritic cells and, in cancer treatment, the development of effector T cell responses to tumor-associated antigens. Control over these processes is exerted by regulatory T cells (Tregs, suppressor macrophages and immunosuppressive cytokines that act in consort to maintain tolerance to self, limit tissue damage, and re-establish tissue homeostasis. Unfortunately, by the time RT for cancer is initiated the tumor-host relationship has already been sculpted in favor of tumor growth and against immune-mediated mechanisms for tumor regression. Reversing this situation is a major challenge. However, recent data show that removal of Tregs can tip the balance in favor of the generation of radiation-induced anti-tumor immunity. The clinical challenge is to do so without excessive depletion that might precipitate serious autoimmune reactions and increase the likelihood of normal tissue complications. The selective modulation of Treg biology to maintain immune tolerance and control of normal tissue damage, while releasing the brakes on anti-tumor immune responses, is a worthy aim with promise for enhancing the therapeutic benefit of RT for cancer.

  14. Emerging Evidence for MicroRNAs as Regulators of Cancer Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, Aisha [Department of Pathology, Henry Ford Hospital, Detroit, MI 48202 (United States); Sholl, Lynette M., E-mail: lmsholl@partners.org [Department of Pathology, Brigham and Women' s Hospital and Harvard Medical School, Boston, MA 02115 (United States)

    2011-10-24

    Cancer stem cells are defined as a subpopulation of cells within a tumor that are capable of self-renewal and differentiation into the heterogeneous cell lineages that comprise the tumor. Many studies indicate that cancer stem cells may be responsible for treatment failure and relapse in cancer patients. The factors that regulate cancer stem cells are not well defined. MicroRNAs (miRNAs) are small non-coding RNAs that regulate translational repression and transcript degradation. miRNAs play a critical role in embryonic and inducible pluripotent stem cell regulation and emerging evidence supports their role in cancer stem cell evolution. To date, miRNAs have been shown to act either as tumor suppressor genes or oncogenes in driving critical gene expression pathways in cancer stem cells in a wide range of human malignancies, including hematopoietic and epithelial tumors and sarcomas. miRNAs involved in cancer stem cell regulation provide attractive, novel therapeutic targets for cancer treatment. This review attempts to summarize progress to date in defining the role of miRNAs in cancer stem cells.

  15. Emerging Evidence for MicroRNAs as Regulators of Cancer Stem Cells

    International Nuclear Information System (INIS)

    Sethi, Aisha; Sholl, Lynette M.

    2011-01-01

    Cancer stem cells are defined as a subpopulation of cells within a tumor that are capable of self-renewal and differentiation into the heterogeneous cell lineages that comprise the tumor. Many studies indicate that cancer stem cells may be responsible for treatment failure and relapse in cancer patients. The factors that regulate cancer stem cells are not well defined. MicroRNAs (miRNAs) are small non-coding RNAs that regulate translational repression and transcript degradation. miRNAs play a critical role in embryonic and inducible pluripotent stem cell regulation and emerging evidence supports their role in cancer stem cell evolution. To date, miRNAs have been shown to act either as tumor suppressor genes or oncogenes in driving critical gene expression pathways in cancer stem cells in a wide range of human malignancies, including hematopoietic and epithelial tumors and sarcomas. miRNAs involved in cancer stem cell regulation provide attractive, novel therapeutic targets for cancer treatment. This review attempts to summarize progress to date in defining the role of miRNAs in cancer stem cells

  16. Plant Cell Adaptive Responses to Microgravity

    Science.gov (United States)

    Kordyum, Elizabeth; Kozeko, Liudmyla; Talalaev, Alexandr

    simulated microgravity and temperature elevation have different effects on the small HSP genes belonging to subfamilies with different subcellular localization: cytosol/nucleus - PsHSP17.1-CII and PsHSP18.1-CI, cloroplasts - PsHSP26.2-Cl, endoplasmatic reticulum - PsHSP22.7-ER and mitochondria - PsHSP22.9-M: unlike high temperature, clinorotation does not cause denaturation of cell proteins, that confirms the sHSP chaperone function. Dynamics of investigated gene expression in pea seedlings growing 5 days after seed germination under clinorotation was similar to that in the stationary control. Similar patterns in dynamics of sHSP gene expression in the stationary control and under clinorotation may be one of mechanisms providing plant adaptation to simulated microgravity. It is pointed that plant cell responses in microgravity and under clinorotation vary according to growth phase, physiological state, and taxonomic position of the object. At the same time, the responses have, to some degree, a similar character reflecting the changes in cell organelle functional load. Thus, next certain changes in the structure and function of plant cells may be considered as adaptive: 1) an increase in the unsaturated fatty acid content in the plasmalemma, 2) rearrangements of organelle ultrastructure and an increase in their functional load, 3) an increase in cortical F-actin under destabilization of tubulin microtubules, 4) the level of gene expression and synthesis of heat shock proteins, 5) alterations of the enzyme and antioxidant system activity. The dynamics of these patterns demonstrated that the adaptation occurs on the principle of self-regulating systems in the limits of physiological norm reaction. The very importance of changed expression of genes involved in different cellular processes, especially HSP genes, in cell adaptation to altered gravity is discussed.

  17. Evidence for two concurrent inhibitory mechanisms during response preparation

    Science.gov (United States)

    Duque, Julie; Lew, David; Mazzocchio, Riccardo; Olivier, Etienne; Ivry, Richard B.

    2010-01-01

    Inhibitory mechanisms are critically involved in goal-directed behaviors. To gain further insight into how such mechanisms shape motor representations during response preparation, motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) and H-reflexes were recorded from left hand muscles during choice reaction time tasks. The imperative signal, which indicated the required response, was always preceded by a preparatory cue. During the post-cue delay period, left MEPs were suppressed when the left hand had been cued for the forthcoming response, suggestive of a form of inhibition specifically directed at selected response representations. H-reflexes were also suppressed on these trials, indicating that the effects of this inhibition extend to spinal circuits. In addition, left MEPs were suppressed when the right hand was cued, but only when left hand movements were a possible response option before the onset of the cue. Notably, left hand H-reflexes were not modulated on these trials, consistent with a cortical locus of inhibition that lowers the activation of task-relevant, but non-selected responses. These results suggest the concurrent operation of two inhibitory mechanisms during response preparation: one decreases the activation of selected responses at the spinal level, helping to control when selected movements should be initiated by preventing their premature release; a second, upstream mechanism helps to determine what response to make during a competitive selection process. PMID:20220014

  18. Cross-talk between cd1d-restricted nkt cells and γδ cells in t regulatory cell response

    Directory of Open Access Journals (Sweden)

    Huber Sally A

    2011-01-01

    Full Text Available Abstract CD1d is a non-classical major histocompatibility class 1-like molecule which primarily presents either microbial or endogenous glycolipid antigens to T cells involved in innate immunity. Natural killer T (NKT cells and a subpopulation of γδ T cells expressing the Vγ4 T cell receptor (TCR recognize CD1d. NKT and Vγ4 T cells function in the innate immune response via rapid activation subsequent to infection and secrete large quantities of cytokines that both help control infection and modulate the developing adaptive immune response. T regulatory cells represent one cell population impacted by both NKT and Vγ4 T cells. This review discusses the evidence that NKT cells promote T regulatory cell activation both through direct interaction of NKT cell and dendritic cells and through NKT cell secretion of large amounts of TGFβ, IL-10 and IL-2. Recent studies have shown that CD1d-restricted Vγ4 T cells, in contrast to NKT cells, selectively kill T regulatory cells through a caspase-dependent mechanism. Vγ4 T cell elimination of the T regulatory cell population allows activation of autoimmune CD8+ effector cells leading to severe cardiac injury in a coxsackievirus B3 (CVB3 myocarditis model in mice. CD1d-restricted immunity can therefore lead to either immunosuppression or autoimmunity depending upon the type of innate effector dominating during the infection.

  19. Households' vulnerability and responses to shocks: evidence from rural Kenya

    NARCIS (Netherlands)

    Ndirangu, L.

    2007-01-01

    Key words: Vulnerability, HIV/AIDS, weather shocks, risk management, coping strategies, rural households, gender. Empirical investigation on household’s responses to sources of vulnerability is important for designing and implementation of social policies. The design of an effective

  20. Interaction with Epithelial Cells Modifies Airway Macrophage Response to Ozone

    Science.gov (United States)

    The initial innate immune response to ozone (03) in the lung is orchestrated by structural cells, such as epithelial cells, and resident immune cells, such as airway macrophages (Macs). We developed an epithelial cell-Mac coculture model to investigate how epithelial cell-derived...

  1. The Perception of Investors on Socially Responsible Investment: International Evidence

    OpenAIRE

    Chiew, Dominic Kia Seng

    2008-01-01

    It is quite impossible to deny the growing importance of socially responsible investing (SRI) since its introduction in the early 1990s (Robson and Wakefield, 2007), when little attention was paid to this subject within the business ethics community as an alternative outlet to the existing conventional investment philosophy (Sparkes, 2001). The increasing use of Socially Responsible Investment (SRI) in the financial markets has become more apparent today. Organization have included many other...

  2. Corporate Social Responsibility and Corporate Financial Performance: Evidence from Korea

    OpenAIRE

    Choi, Jong-Seo; Kwak, Young-Min; Choe, Chongwoo

    2010-01-01

    This paper studies the empirical relation between corporate social responsibility (CSR) and corporate financial performance in Korea using a sample of 1122 firm-years during 2002-2008. We measure corporate social responsibility by both an equal-weighted CSR index and a stakeholder-weighted CSR index suggested by Akpinar et al. (2008). Corporate financial performance is measured by ROE, ROA and Tobin’s Q. We find a positive and significant relation between corporate financial performance and t...

  3. CORPORATE PHILANTHROPIC DISASTER RESPONSE AND POST PERFORMANCE: EVIDENCE FROM CHINA

    OpenAIRE

    Xiaodong Qiu

    2013-01-01

    This paper examines whether the decision and amount of firm charitable giving in response to catastrophic events are related to firm post-performance, and whether firm ownership type moderates this relationship. Using data on Chinese firms’ philanthropic response to the 2008 Sichuan earthquake, we find that firm future sales growth and ROA change are positively associated with both the probability and the amount of corporate giving. The results also indicate that this positive philanthropic...

  4. Hemopoietic cell precursor responses to erythropoietin in plasma clot cultures

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, W.L.

    1979-01-01

    The time dependence of the response of mouse bone marrow cells to erythropoietin (Ep) in vitro was studied. Experiments include studies on the Ep response of marrow cells from normal, plethoric, or bled mice. Results with normal marrow reveal: (1) Not all erythroid precursors (CFU-E) are alike in their response to Ep. A significant number of the precursors develop to a mature erythroid colony after very short Ep exposures, but they account for only approx. 13% of the total colonies generated when Ep is active for 48 hrs. If Ep is active more than 6 hrs, a second population of erythroid colonies emerges at a nearly constant rate until the end of the culture. Full erythroid colony production requires prolonged exposure to erythropoietin. (2) The longer erythropoietin is actively present, the larger the number of erythroid colonies that reach 17 cells or more. Two distinct populations of immediate erythroid precursors are also present in marrow from plethoric mice. In these mice, total colony numbers are equal to or below those obtained from normal mice. However, the population of fast-responding CFU-E is consistently decreased to 10 to 20% of that found in normal marrow. The remaining colonies are formed from plethoric marrow at a rate equal to normal marrow. With increasing Ep exposures, the number of large colonies produced increases. From the marrow of bled mice, total erythroid colony production is equal to or above that of normal marrow. Two populations of colony-forming cells are again evident, with the fast-responding CFU-E being below normal levels. The lack of colonies from this group was compensated in bled mice by rapid colony production in the second population. A real increase in numbers of precursors present in this pool increased the rate of colony production in culture to twice that of normal marrow. The number of large colonies obtained from bled mice was again increased as the Ep exposure was lengthened. (ERB)

  5. Response of a direct methanol fuel cell to fuel change

    Energy Technology Data Exchange (ETDEWEB)

    Leo, T.J. [Dpto de Sistemas Oceanicos y Navales- ETSI Navales, Univ. Politecnica de Madrid, Avda Arco de la Victoria s/n, 28040 Madrid (Spain); Raso, M.A.; de la Blanca, E. Sanchez [Dpto de Quimica Fisica I- Fac. CC. Quimicas, Univ. Complutense de Madrid, Avda Complutense s/n, 28040 Madrid (Spain); Navarro, E.; Villanueva, M. [Dpto de Motopropulsion y Termofluidodinamica, ETSI Aeronauticos, Univ. Politecnica de Madrid, Pza Cardenal Cisneros 3, 28040 Madrid (Spain); Moreno, B. [Instituto de Ceramica y Vidrio, Consejo Superior de Investigaciones Cientificas, C/Kelsen 5, Campus de la UAM, 28049 Cantoblanco, Madrid (Spain)

    2010-10-15

    Methanol and ethanol have recently received much attention as liquid fuels particularly as alternative 'energy-vectors' for the future. In this sense, to find a direct alcohol fuel cell that able to interchange the fuel without losing performances in an appreciable way would represent an evident advantage in the field of portable applications. In this work, the response of a in-house direct methanol fuel cell (DMFC) to the change of fuel from methanol to ethanol and its behaviour at different ambient temperature values have been investigated. A corrosion study on materials suitable to fabricate the bipolar plates has been carried out and either 316- or 2205-duplex stainless steels have proved to be adequate for using in direct alcohol fuel cells. Polarization curves have been measured at different ambient temperature values, controlled by an experimental setup devised for this purpose. Data have been fitted to a model taking into account the temperature effect. For both fuels, methanol and ethanol, a linear dependence of adjustable parameters with temperature is obtained. Fuel cell performance comparison in terms of open circuit voltage, kinetic and resistance is established. (author)

  6. Metabolic features of the cell danger response.

    Science.gov (United States)

    Naviaux, Robert K

    2014-05-01

    The cell danger response (CDR) is the evolutionarily conserved metabolic response that protects cells and hosts from harm. It is triggered by encounters with chemical, physical, or biological threats that exceed the cellular capacity for homeostasis. The resulting metabolic mismatch between available resources and functional capacity produces a cascade of changes in cellular electron flow, oxygen consumption, redox, membrane fluidity, lipid dynamics, bioenergetics, carbon and sulfur resource allocation, protein folding and aggregation, vitamin availability, metal homeostasis, indole, pterin, 1-carbon and polyamine metabolism, and polymer formation. The first wave of danger signals consists of the release of metabolic intermediates like ATP and ADP, Krebs cycle intermediates, oxygen, and reactive oxygen species (ROS), and is sustained by purinergic signaling. After the danger has been eliminated or neutralized, a choreographed sequence of anti-inflammatory and regenerative pathways is activated to reverse the CDR and to heal. When the CDR persists abnormally, whole body metabolism and the gut microbiome are disturbed, the collective performance of multiple organ systems is impaired, behavior is changed, and chronic disease results. Metabolic memory of past stress encounters is stored in the form of altered mitochondrial and cellular macromolecule content, resulting in an increase in functional reserve capacity through a process known as mitocellular hormesis. The systemic form of the CDR, and its magnified form, the purinergic life-threat response (PLTR), are under direct control by ancient pathways in the brain that are ultimately coordinated by centers in the brainstem. Chemosensory integration of whole body metabolism occurs in the brainstem and is a prerequisite for normal brain, motor, vestibular, sensory, social, and speech development. An understanding of the CDR permits us to reframe old concepts of pathogenesis for a broad array of chronic, developmental

  7. The Price of Ethics : Evidence from Socially Responsible Mutual Funds

    NARCIS (Netherlands)

    Renneboog, L.D.R.; Ter Horst, J.R.; Zhang, C.

    2007-01-01

    This paper estimates the price of ethics by studying the risk-return relation in socially responsible investment (SRI) funds. Consistent with investors paying a price for ethics, SRI funds in many European and Asia-Pacific countries strongly underperform domestic benchmark portfolios by about 5% per

  8. Dose-response relationship with radiotherapy: an evidence?

    International Nuclear Information System (INIS)

    Chauvet, B.; Rauglaudre, G. de; Mineur, L.; Alfonsi, M.; Reboul, F.

    2003-01-01

    The dose-response relationship is a fundamental basis of radiobiology. Despite many clinical data, difficulties remain to demonstrate a relation between dose and local control: relative role of treatment associated with radiation therapy (surgery, chemotherapy, hormonal therapy), tumor heterogeneity, few prospective randomized studies, uncertainty of local control assessment. Three different situations are discussed: tumors with high local control probabilities for which dose effect is demonstrated by randomized studies (breast cancer) or sound retrospective data (soft tissues sarcomas), tumors with intermediate local control probabilities for which dose effect seems to be important according to retrospective studies and ongoing or published phase III trials (prostate cancer), tumors with low local control probabilities for which dose effect appears to be modest beyond standard doses, and inferior to the benefit of concurrent chemotherapy (lung and oesophageal cancer). For head and neck tumors, the dose-response relationship has been explored through hyperfractionation and accelerated radiation therapy and a dose effect has been demonstrated but must be compared to the benefit of concurrent chemotherapy. Last but not least, the development of conformal radiotherapy allow the exploration of the dose response relationship for tumors such as hepatocellular carcinomas traditionally excluded from the field of conventional radiation therapy. In conclusion, the dose-response relationship remains a sound basis of radiation therapy for many tumors and is a parameter to take into account for further randomized studies. (author)

  9. Corporate Social Responsibility and Earnings Management : Evidence from Asian Economies

    NARCIS (Netherlands)

    Scholtens, Bert; Kang, Feng-Ching

    2013-01-01

    We investigate how earnings management is associated with corporate social responsibility (CSR) and investor protection with 139 firms in ten Asian countries. In Asia, CSR is increasingly attracting attention but the legal system generally is perceived as being poor. We hypothesize that there is an

  10. Muscarinic responses of gastric parietal cells

    International Nuclear Information System (INIS)

    Wilkes, J.M.; Kajimura, M.; Scott, D.R.; Hersey, S.J.; Sachs, G.

    1991-01-01

    Isolated rabbit gastric glands were used to study the nature of the muscarinic cholinergic responses of parietal cells. Carbachol stimulation of acid secretion, as measured by the accumulation of aminopyrine, was inhibited by the M1 antagonist, pirenzepine, with an IC50 of 13 microM; by the M2 antagonist, 11,2-(diethylamino)methyl-1 piperidinyl acetyl-5,11-dihydro-6H-pyrido 2,3-b 1,4 benzodiazepin-6-one (AF-DX 116), with an IC50 of 110 microM; and by the M1/M3 antagonist, diphenyl-acetoxy-4-methylpiperidinemethiodide, with an IC50 of 35 nM. The three antagonists displayed equivalent IC50 values for the inhibition of carbachol-stimulated production of 14CO2 from radiolabeled glucose, which is a measure of the turnover of the H,K-ATPase, the final step of acid secretion. Intracellular calcium levels were measured in gastric glands loaded with FURA 2. Carbachol was shown to both release calcium from an intracellular pool and to promote calcium entry across the plasma membrane. The calcium entry was inhibitable by 20 microM La3+. The relative potency of the three muscarinic antagonists for inhibition of calcium entry was essentially the same as for inhibition of acid secretion or pump related glucose oxidation. Image analysis of the glands showed the effects of carbachol, and of the antagonists, on intracellular calcium were occurring largely in the parietal cell. The rise in cell calcium due to release of calcium from intracellular stores was inhibited by 4-DAMP with an IC50 of 1.7 nM, suggesting that the release pathway was regulated by a low affinity M3 muscarinic receptor or state; Ca entry and acid secretion are regulated by a high affinity M3 muscarinic receptor or state, inhibited by higher 4-DAMP concentrations, suggesting that it is the steady-state elevation of Ca that is related to parietal cell function rather than the [Ca]i transient

  11. Novel sex cells and evidence for sex pheromones in diatoms.

    Science.gov (United States)

    Sato, Shinya; Beakes, Gordon; Idei, Masahiko; Nagumo, Tamotsu; Mann, David G

    2011-01-01

    Diatoms belong to the stramenopiles, one of the largest groups of eukaryotes, which are primarily characterized by a presence of an anterior flagellum with tubular mastigonemes and usually a second, smooth flagellum. Based on cell wall morphology, diatoms have historically been divided into centrics and pennates, of which only the former have flagella and only on the sperm. Molecular phylogenies show the pennates to have evolved from among the centrics. However, the timing of flagellum loss--whether before the evolution of the pennate lineage or after--is unknown, because sexual reproduction has been so little studied in the 'araphid' basal pennate lineages, to which Pseudostaurosira belongs. Sexual reproduction of an araphid pennate, Pseudostaurosira trainorii, was studied with light microscopy (including time lapse observations and immunofluorescence staining observed under confocal scanning laser microscopy) and SEM. We show that the species produces motile male gametes. Motility is mostly associated with the extrusion and retrieval of microtubule-based 'threads', which are structures hitherto unknown in stramenopiles, their number varying from one to three per cell. We also report experimental evidence for sex pheromones that reciprocally stimulate sexualization of compatible clones and orientate motility of the male gametes after an initial 'random walk'. The threads superficially resemble flagella, in that both are produced by male gametes and contain microtubules. However, one striking difference is that threads cannot beat or undulate and have no motility of their own, and they do not bear mastigonemes. Threads are sticky and catch and draw objects, including eggs. The motility conferred by the threads is probably crucial for sexual reproduction of P. trainorii, because this diatom is non-motile in its vegetative stage but obligately outbreeding. Our pheromone experiments are the first studies in which gametogenesis has been induced in diatoms by cell

  12. Novel sex cells and evidence for sex pheromones in diatoms.

    Directory of Open Access Journals (Sweden)

    Shinya Sato

    Full Text Available BACKGROUND: Diatoms belong to the stramenopiles, one of the largest groups of eukaryotes, which are primarily characterized by a presence of an anterior flagellum with tubular mastigonemes and usually a second, smooth flagellum. Based on cell wall morphology, diatoms have historically been divided into centrics and pennates, of which only the former have flagella and only on the sperm. Molecular phylogenies show the pennates to have evolved from among the centrics. However, the timing of flagellum loss--whether before the evolution of the pennate lineage or after--is unknown, because sexual reproduction has been so little studied in the 'araphid' basal pennate lineages, to which Pseudostaurosira belongs. METHODS/PRINCIPAL FINDING: Sexual reproduction of an araphid pennate, Pseudostaurosira trainorii, was studied with light microscopy (including time lapse observations and immunofluorescence staining observed under confocal scanning laser microscopy and SEM. We show that the species produces motile male gametes. Motility is mostly associated with the extrusion and retrieval of microtubule-based 'threads', which are structures hitherto unknown in stramenopiles, their number varying from one to three per cell. We also report experimental evidence for sex pheromones that reciprocally stimulate sexualization of compatible clones and orientate motility of the male gametes after an initial 'random walk'. CONCLUSIONS/SIGNIFICANCE: The threads superficially resemble flagella, in that both are produced by male gametes and contain microtubules. However, one striking difference is that threads cannot beat or undulate and have no motility of their own, and they do not bear mastigonemes. Threads are sticky and catch and draw objects, including eggs. The motility conferred by the threads is probably crucial for sexual reproduction of P. trainorii, because this diatom is non-motile in its vegetative stage but obligately outbreeding. Our pheromone experiments

  13. Cell envelope stress response in cell wall-deficient L-forms of Bacillus subtilis.

    Science.gov (United States)

    Wolf, Diana; Domínguez-Cuevas, Patricia; Daniel, Richard A; Mascher, Thorsten

    2012-11-01

    L-forms are cell wall-deficient bacteria that can grow and proliferate in osmotically stabilizing media. Recently, a strain of the Gram-positive model bacterium Bacillus subtilis was constructed that allowed controlled switching between rod-shaped wild-type cells and corresponding L-forms. Both states can be stably maintained under suitable culture conditions. Because of the absence of a cell wall, L-forms are known to be insensitive to β-lactam antibiotics, but reports on the susceptibility of L-forms to other antibiotics that interfere with membrane-anchored steps of cell wall biosynthesis are sparse, conflicting, and strongly influenced by strain background and method of L-form generation. Here we investigated the response of B. subtilis to the presence of cell envelope antibiotics, with regard to both antibiotic resistance and the induction of the known LiaRS- and BceRS-dependent cell envelope stress biosensors. Our results show that B. subtilis L-forms are resistant to antibiotics that interfere with the bactoprenol cycle, such as bacitracin, vancomycin, and mersacidin, but are hypersensitive to nisin and daptomycin, which both affect membrane integrity. Moreover, we established a lacZ-based reporter gene assay for L-forms and provide evidence that LiaRS senses its inducers indirectly (damage sensing), while the Bce module detects its inducers directly (drug sensing).

  14. 20 CFR 416.1014 - Responsibilities for obtaining evidence to make disability determinations.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Responsibilities for obtaining evidence to make disability determinations. 416.1014 Section 416.1014 Employees' Benefits SOCIAL SECURITY... Responsibilities for Performing the Disability Determination Function § 416.1014 Responsibilities for obtaining...

  15. 20 CFR 404.1614 - Responsibilities for obtaining evidence to make disability determinations.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Responsibilities for obtaining evidence to make disability determinations. 404.1614 Section 404.1614 Employees' Benefits SOCIAL SECURITY... Responsibilities for Performing the Disability Determination Function § 404.1614 Responsibilities for obtaining...

  16. Cardio–Pulmonary Response Of Patients With Sickle Cell Anaemia ...

    African Journals Online (AJOL)

    Cardio–Pulmonary Response Of Patients With Sickle Cell Anaemia ... any risk of adverse cardio-respiratory response during the course of physical rehabilitation. A total of 70 subjects participated in the study; 30 of these had Haemoglobin ...

  17. Normalization of cell responses in cat striate cortex

    Science.gov (United States)

    Heeger, D. J.

    1992-01-01

    Simple cells in the striate cortex have been depicted as half-wave-rectified linear operators. Complex cells have been depicted as energy mechanisms, constructed from the squared sum of the outputs of quadrature pairs of linear operators. However, the linear/energy model falls short of a complete explanation of striate cell responses. In this paper, a modified version of the linear/energy model is presented in which striate cells mutually inhibit one another, effectively normalizing their responses with respect to stimulus contrast. This paper reviews experimental measurements of striate cell responses, and shows that the new model explains a significantly larger body of physiological data.

  18. Bone marrow function. I. Peripheral T cells are responsible for the increased auto-antiidiotype response of older mice

    International Nuclear Information System (INIS)

    Kim, Y.T.; Goidl, E.A.; Samarut, C.; Weksler, M.E.; Thorbecke, G.J.; Siskind, G.W.

    1985-01-01

    After immunization with trinitrophenyl (TNP)-Ficoll, mice produced both anti-TNP antibodies and auto-anti-idiotype (auto-anti-Id) antibodies specific for the anti-TNP antibody. Older animals produced more auto-anti-Id than did young animals. When mice were exposed to a normally lethal dose of irradiation while their bone marrow (BM) was partially shielded, they survived and slowly (6 wk) regained immune function, as indicated by the number of nucleated cells in their spleen and the in vitro primary plaque-forming cell (PFC) response of their spleen cells to TNP-treated aminoethylated polyacrylamide beads. Recovery is presumably the result of repopulation of the peripheral lymphoid system by cells originating in the BM. By enzyme-linked immunosorbent assay (ELISA), and by hapten-augmentable PFC assay, the authors show that, after recovery from irradiation with their BM shielded, old animals produce low auto-anti-Id responses, like those of young animals. The transfer of splenic T cells into mice irradiated with their BM shielded provided evidence that the magnitude of the auto-anti-Id response is controlled by the peripheral T cells. Thus, mice that received splenic T cells from aged donors produced high levels of auto-anti-Id while those that received splenic T cells from young donors produce low levels of auto-anti-Id

  19. Modulation of Dendritic Cell Responses by Parasites: A Common Strategy to Survive

    Directory of Open Access Journals (Sweden)

    César A. Terrazas

    2010-01-01

    Full Text Available Parasitic infections are one of the most important causes of morbidity and mortality in our planet and the immune responses triggered by these organisms are critical to determine their outcome. Dendritic cells are key elements for the development of immunity against parasites; they control the responses required to eliminate these pathogens while maintaining host homeostasis. However, there is evidence showing that parasites can influence and regulate dendritic cell function in order to promote a more permissive environment for their survival. In this review we will focus on the strategies protozoan and helminth parasites have developed to interfere with dendritic cell activities as well as in the possible mechanisms involved.

  20. Evidence against the involvement of ionically bound cell wall proteins in pea epicotyl growth

    Science.gov (United States)

    Melan, M. A.; Cosgrove, D. J.

    1988-01-01

    Ionically bound cell wall proteins were extracted from 7 day old etiolated pea (Pisum sativum L. cv Alaska) epicotyls with 3 molar LiCl. Polyclonal antiserum was raised in rabbits against the cell wall proteins. Growth assays showed that treatment of growing region segments (5-7 millimeters) of peas with either dialyzed serum, serum globulin fraction, affinity purified immunoglobulin, or papain-cleaved antibody fragments had no effect on growth. Immunofluorescence microscopy confirmed antibody binding to cell walls and penetration of the antibodies into the tissues. Western blot analysis, immunoassay results, and affinity chromatography utilizing Sepharose-bound antibodies confirmed recognition of the protein preparation by the antibodies. Experiments employing in vitro extension as a screening measure indicated no effect upon extension by antibodies, by 50 millimolar LiCl perfusion of the apoplast or by 3 molar LiCl extraction. Addition of cell wall protein to protease pretreated segments did not restore extension nor did addition of cell wall protein to untreated segments increase extension. It is concluded that, although evidence suggests that protein is responsible for the process of extension, the class(es) of proteins which are extracted from pea cell walls with 3 molar LiCl are probably not involved in this process.

  1. Response to "Critical Assessment of the Evidence for Striped Nanoparticles".

    Directory of Open Access Journals (Sweden)

    Quy Khac Ong

    Full Text Available Stirling et al., (10.1371/journal.pone.0108482 presented an analysis on some of our publications on the formation of stripe-like domains on mixed-ligand coated gold nanoparticles. The authors shed doubts on some of our results however no valid argument is provided against what we have shown since our first publication: scanning tunneling microscopy (STM images of striped nanoparticles show stripe-like domains that are independent of imaging parameters and in particular of imaging speed. We have consistently ruled out the presence of artifacts by comparing sets of images acquired at different tip speeds, finding invariance of the stipe-like domains. Stirling and co-workers incorrectly analyzed this key control, using a different microscope and imaging conditions that do not compare to ours. We show here data proving that our approach is rigorous. Furthermore, we never solely relied on image analysis to draw our conclusions; we have always used the chemical nature of the particles to assess the veracity of our images. Stirling et al. do not provide any justification for the spacing of the features that we find on nanoparticles: ~1 nm for mixed ligand particles and ~ 0.5 nm for homoligand particles. Hence our two central arguments remain unmodified: independence from imaging parameters and dependence on ligand shell chemical composition. The paper report observations on our STM images; none is a sufficient condition to prove that our images are artifacts. We thoroughly addressed issues related to STM artifacts throughout our microscopy work. Stirling et al. provide guidelines for what they consider good STM images of nanoparticles, such images are indeed present in our literature. They conclude that the evidences we provided to date are insufficient, this is a departure from one of the authors' previous article which concluded that our images were composed of artifacts. Given that four independent laboratories have reproduced our measurements and

  2. B Cells Promote Th1- Skewed NKT Cell Response by CD1d-TCR Interaction

    OpenAIRE

    Shin, Jung Hoon; Park, Se-Ho

    2013-01-01

    CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although ?-galactosylceramide (?-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-? by NKT cells, concomitant with a d...

  3. Evidence for some signal transduction elements involved in UV-light-dependent responses in parsley protoplasts

    International Nuclear Information System (INIS)

    Frohnmeyer, H.; Bowler, C.; Schäfer, E.

    1997-01-01

    The signalling pathways used by UV-light are largely unknown. Using protoplasts from a heterotrophic parsley (Petroselinum crispum L.) cell culture that exclusively respond to UV-B light between 300 and 350 nm with a fast induction of genes encoding flavonoid biosynthetic enzymes, information was obtained about the UV-light signal transduction pathway for chalcone synthase (CHS) and phenylalanine ammonia-lyase (PAL) gene expression. Pharmacological effectors which influence intracellular calcium levels, calmodulin and the activity of serine/threonine kinases also changed the UV-light-dependent expression of these genes. This evaluation indicated the participation of these components on the UV-B-mediated signal transduction cascade to CHS. In contrast, neither membrane-permeable cyclic GMP nor the tyrosine kinase inhibitor genistein affected CHS or PAL expression. Similar results were obtained in protoplasts, which have been transiently transformed with CHS-promoter/GUS (β-glucuronidase) reporter fusion constructs. The involvement of calcium and calmodulin was further indicated in a cell-free light-responsive in vitro transcription system from evacuolated parsley protoplasts. In conclusion, there is evidence now that components of the UV-light-dependent pathway leading to the CHS-promoter are different from the previously characterized cGMP-dependent pathway to CHS utilized by phytochrome in soybean (Glycine max) and tomato seedlings (Lycopersicon esculentum). (author)

  4. Response of thyroid follicular cells to accelerated iron ions

    International Nuclear Information System (INIS)

    Green, L.M.; Bianski, B.M.

    2003-01-01

    Full text: Suspension cultures of early and later passages thyroid follicular fisher rat thyroid cells (FRTL-5) were exposed to iron ions delivered over a dose range of 0-3 Gy and their comparative biological responses measured. Early passage FRTL-5 cultures are slow-growing, connexin32 competent whereas, later passage cultures are relatively rapidly growing and connexin32 defective. The iron-irradiated cells had sustained levels of incorporated dUTP into 3' strand breaks, reflecting DNA damage. There were no significant differences between early and later passage cultures except at 0.5 and 1 Gy, 48-hours (p 0.05). The presence of consistently medium-larger micronuclei was evidence that severe damage was introduced by exposure to iron ions. The levels of apoptosis were not linear with dose, nor was there a marked difference with time. In all cases the 3 Gy levels were less than or equal to the levels measured at 0.5 Gy. When survival characteristics were compared the most significant difference between early and later passage cultures were in the a-components of the survival curves (0.60 Gy -1 for early and 0.71 Gy-1 for the later passage cultures, p<0.014). When cell cycle phase redistribution was measured, both the early and later passage cultures displayed a significant shift toward G2 (p<0.001). In conclusion, these findings suggest that neither the presence of gap junctions, nor the differences in growth rate translated to significant differences in the biological response of thyroid follicles to iron ions

  5. Stochasticity in the enterococcal sex pheromone response revealed by quantitative analysis of transcription in single cells.

    Science.gov (United States)

    Breuer, Rebecca J; Bandyopadhyay, Arpan; O'Brien, Sofie A; Barnes, Aaron M T; Hunter, Ryan C; Hu, Wei-Shou; Dunny, Gary M

    2017-07-01

    In Enterococcus faecalis, sex pheromone-mediated transfer of antibiotic resistance plasmids can occur under unfavorable conditions, for example, when inducing pheromone concentrations are low and inhibiting pheromone concentrations are high. To better understand this paradox, we adapted fluorescence in situ hybridization chain reaction (HCR) methodology for simultaneous quantification of multiple E. faecalis transcripts at the single cell level. We present direct evidence for variability in the minimum period, maximum response level, and duration of response of individual cells to a specific inducing condition. Tracking of induction patterns of single cells temporally using a fluorescent reporter supported HCR findings. It also revealed subpopulations of rapid responders, even under low inducing pheromone concentrations where the overall response of the entire population was slow. The strong, rapid induction of small numbers of cells in cultures exposed to low pheromone concentrations is in agreement with predictions of a stochastic model of the enterococcal pheromone response. The previously documented complex regulatory circuitry controlling the pheromone response likely contributes to stochastic variation in this system. In addition to increasing our basic understanding of the biology of a horizontal gene transfer system regulated by cell-cell signaling, demonstration of the stochastic nature of the pheromone response also impacts any future efforts to develop therapeutic agents targeting the system. Quantitative single cell analysis using HCR also has great potential to elucidate important bacterial regulatory mechanisms not previously amenable to study at the single cell level, and to accelerate the pace of functional genomic studies.

  6. Evidences Suggesting Involvement of Viruses in Oral Squamous Cell Carcinoma

    Science.gov (United States)

    Gupta, Kanupriya; Metgud, Rashmi

    2013-01-01

    Oral cancer is one of the most common cancers and it constitutes a major health problem particularly in developing countries. Oral squamous cell carcinoma (OSCC) represents the most frequent of all oral neoplasms. Several risk factors have been well characterized to be associated with OSCC with substantial evidences. The etiology of OSCC is complex and involves many factors. The most clearly defined potential factors are smoking and alcohol, which substantially increase the risk of OSCC. However, despite this clear association, a substantial proportion of patients develop OSCC without exposure to them, emphasizing the role of other risk factors such as genetic susceptibility and oncogenic viruses. Some viruses are strongly associated with OSCC while the association of others is less frequent and may depend on cofactors for their carcinogenic effects. Therefore, the exact role of viruses must be evaluated with care in order to improve the diagnosis and treatment of OSCC. Although a viral association within a subset of OSCC has been shown, the molecular and histopathological characteristics of these tumors have yet to be clearly defined. PMID:24455418

  7. Evidences Suggesting Involvement of Viruses in Oral Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Kanupriya Gupta

    2013-01-01

    Full Text Available Oral cancer is one of the most common cancers and it constitutes a major health problem particularly in developing countries. Oral squamous cell carcinoma (OSCC represents the most frequent of all oral neoplasms. Several risk factors have been well characterized to be associated with OSCC with substantial evidences. The etiology of OSCC is complex and involves many factors. The most clearly defined potential factors are smoking and alcohol, which substantially increase the risk of OSCC. However, despite this clear association, a substantial proportion of patients develop OSCC without exposure to them, emphasizing the role of other risk factors such as genetic susceptibility and oncogenic viruses. Some viruses are strongly associated with OSCC while the association of others is less frequent and may depend on cofactors for their carcinogenic effects. Therefore, the exact role of viruses must be evaluated with care in order to improve the diagnosis and treatment of OSCC. Although a viral association within a subset of OSCC has been shown, the molecular and histopathological characteristics of these tumors have yet to be clearly defined.

  8. Stress responses in flavivirus-infected cells: activation of unfolded protein response and autophagy

    Directory of Open Access Journals (Sweden)

    Ana-Belén eBlázquez

    2014-06-01

    Full Text Available The Flavivirus is a genus of RNA viruses that includes multiple long known human, animal and zoonotic pathogens such as Dengue virus, yellow fever virus, West Nile virus or Japanese encephalitis virus, as well as other less known viruses that represent potential threats for human and animal health such as Usutu or Zika viruses. Flavivirus replication is based on endoplasmic reticulum-derived structures. Membrane remodeling and accumulation of viral factors induce endoplasmic reticulum stress that results in activation of a cellular signaling response termed unfolded protein response (UPR, which can be modulated by the viruses for their own benefit. Concomitant with the activation of the UPR, an upregulation of the autophagic pathway in cells infected with different flaviviruses has also been described. This review addresses the current knowledge of the relationship between endoplasmic reticulum stress, UPR and autophagy in flavivirus-infected cells and the growing evidences for an involvement of these cellular pathways in the replication and pathogenesis of these viruses.

  9. Regulation of Cancer Cell Responsiveness to Ionizing Radiation Treatment by Cyclic AMP Response Element Binding Nuclear Transcription Factor

    Directory of Open Access Journals (Sweden)

    Francesca D’Auria

    2017-05-01

    Full Text Available Cyclic AMP response element binding (CREB protein is a member of the CREB/activating transcription factor (ATF family of transcription factors that play an important role in the cell response to different environmental stimuli leading to proliferation, differentiation, apoptosis, and survival. A number of studies highlight the involvement of CREB in the resistance to ionizing radiation (IR therapy, demonstrating a relationship between IR-induced CREB family members’ activation and cell survival. Consistent with these observations, we have recently demonstrated that CREB and ATF-1 are expressed in leukemia cell lines and that low-dose radiation treatment can trigger CREB activation, leading to survival of erythro-leukemia cells (K562. On the other hand, a number of evidences highlight a proapoptotic role of CREB following IR treatment of cancer cells. Since the development of multiple mechanisms of resistance is one key problem of most malignancies, including those of hematological origin, it is highly desirable to identify biological markers of responsiveness/unresponsiveness useful to follow-up the individual response and to adjust anticancer treatments. Taking into account all these considerations, this mini-review will be focused on the involvement of CREB/ATF family members in response to IR therapy, to deepen our knowledge of this topic, and to pave the way to translation into a therapeutic context.

  10. B Cells Promote Th1- Skewed NKT Cell Response by CD1d-TCR Interaction.

    Science.gov (United States)

    Shin, Jung Hoon; Park, Se-Ho

    2013-10-01

    CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although α-galactosylceramide (α-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-γ by NKT cells, concomitant with a decreased level of IL-4, in the circumstance of co-culture of DCs and B Cells. Remarkably, the response promoted by B cells was dependent on CD1d expression of B cells.

  11. Nanomaterials for Engineering Stem Cell Responses.

    Science.gov (United States)

    Kerativitayanan, Punyavee; Carrow, James K; Gaharwar, Akhilesh K

    2015-08-05

    Recent progress in nanotechnology has stimulated the development of multifunctional biomaterials for tissue engineering applications. Synergistic interactions between nanomaterials and stem cell engineering offer numerous possibilities to address some of the daunting challenges in regenerative medicine, such as controlling trigger differentiation, immune reactions, limited supply of stem cells, and engineering complex tissue structures. Specifically, the interactions between stem cells and their microenvironment play key roles in controlling stem cell fate, which underlines therapeutic success. However, the interactions between nanomaterials and stem cells are not well understood, and the effects of the nanomaterials shape, surface morphology, and chemical functionality on cellular processes need critical evaluation. In this Review, focus is put on recent development in nanomaterial-stem cell interactions, with specific emphasis on their application in regenerative medicine. Further, the emerging technologies based on nanomaterials developed over the past decade for stem cell engineering are reviewed, as well as the potential applications of these nanomaterials in tissue regeneration, stem cell isolation, and drug/gene delivery. It is anticipated that the enhanced understanding of nanomaterial-stem cell interactions will facilitate improved biomaterial design for a range of biomedical and biotechnological applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Evident?

    DEFF Research Database (Denmark)

    Plant, Peter

    2012-01-01

    Quality assurance and evidence in career guidance in Europe are often seen as self-evident approaches, but particular interests lie behind......Quality assurance and evidence in career guidance in Europe are often seen as self-evident approaches, but particular interests lie behind...

  13. Investigation of the response of low-dose irradiated cells. Pt. 2. Radio-adaptive response of human embryonic cells is related to cell-to-cell communication

    International Nuclear Information System (INIS)

    Ishii, Keiichiro; Watanabe, Masami.

    1994-01-01

    To clarify the radio-adaptive response of normal cells to low-dose radiation, we irradiated human embryonic cells and HeLa cells with low-dose X-ray and examined the changes in sensitivity to subsequent high-dose X-irradiation. The results obtained were as follows; (1) When HE cells were irradiated by a high-dose of 200 cGy, the growth ratio of the living cells five days after the irradiation decreased to 37% of that of the cells which received no X-irradiation. When the cells received a preliminary irradiation of 10 to 20 cGy four hours before the irradiation of 200 cGy, the relative growth ratios increased significantly to 45-53%. (2) This preliminary irradiation effect was not observed in HeLa cells, being cancer cells. (3) When the HE cells suspended in a Ca 2+ iron-free medium or TPA added medium while receiving the preliminary irradiation of 13 cGy, the effect of the preliminary irradiation in increasing the relative growth ratio of living cells was not observed. (4) This indicates that normal cells shows an adaptive response to low-dose radiation and become more radioresistant. This phenomenon is considered to involve cell-to-cell communication maintained in normal cells and intracellular signal transduction in which Ca 2+ ion plays a role. (author)

  14. CD1d expression and invariant NKT cell responses in herpesvirus infections

    Directory of Open Access Journals (Sweden)

    Rusung eTan

    2015-06-01

    Full Text Available Invariant natural killer T (iNKT cells are a highly conserved subset of unconventional T lymphocytes that express a canonical, semi-invariant T cell receptor (TCR and surface markers shared with the natural killer cell lineage. iNKT cells recognize exogenous and endogenous glycolipid antigens restricted by non-polymorphic CD1d molecules, and are highly responsive to the prototypical agonist, α-galactosylceramide. Upon activation, iNKT cells rapidly coordinate signaling between innate and adaptive immune cells through the secretion of proinflammatory cytokines, leading to the maturation of antigen-presenting cells and expansion of antigen-specific CD4+ and CD8+ T cells. Because of their potent immunoregulatory properties, iNKT cells have been extensively studied and are known to play a pivotal role in mediating immune responses against microbial pathogens including viruses. Here, we review evidence that herpesviruses manipulate CD1d expression to escape iNKT cell surveillance and establish lifelong latency in humans. Collectively, published findings suggest that iNKT cells play critical roles in anti-herpesvirus immune responses and could be harnessed therapeutically to limit viral infection and viral-associated disease.

  15. Stem Cells Matter in Response to Fasting

    Directory of Open Access Journals (Sweden)

    Badi Sri Sailaja

    2015-12-01

    Full Text Available The molecular processes underlying intestinal adaptation to fasting and re-feeding remain largely uncharacterized. In this issue of Cell Reports, Richmond et al. report that dormant intestinal stem cells are regulated by PTEN and nutritional status.

  16. Inhibition of erythroid cell growth by allogeneic murine lymphocytes. Evidence for a synergism between lymph node cells and thymocytes

    International Nuclear Information System (INIS)

    Blomgren, H.; Jacobsson, H.

    1974-01-01

    Murine lymphoid cells from thymus and lymph nodes were tested for synergistic response in a graft-vs-host test. The test is based on the principle that allogeneic lymphocytes inhibit erythroid cell proliferation in the spleens of irradiated mice infused with syngeneic bone marrow cells. Mixtures of thymocytes and lymph node cells from the same parental strain yielded graft-vs-host responses in irradiated F 1 -hybrids higher than expected by summing the responses of the two cell populations tested separately. A similar synergistic response was obtained using mixtures of thymocytes and lymph node cells obtained from the two parental strains of the hybrid, whereas such an effect was not detected using mixtures of lymph node cells or mixtures of thymocytes from the two parental strains. Nor could synergy be demonstrated between parental strain lymph node cells and thymocytes syngeneic with the bone marrow target cells. Thymocytes obtained from one parental strain which was injected into its irradiated F 1 -hybrid transformed into a population of sensitized cells in the spleens of the recipients. This transformation was suppressed by the simultaneous injection of lymph node cells from the second parental strain. Since there is a synergistic immune response by such cell mixtures it is concluded that thymocytes may enhance the graft-vs-host response of lymph node cells. Parental strain thymocytes and lymph node cells, the latter being specifically immunologically tolerant to the bone marrow target cells, failed to give a synergistic response indicating that thymocytes do not transform unresponsive lymphocytes into responsive, but rather enhance the reactivity of existing, specifically responsive cells. The results thus show that thymocytes may enhance the response of lymph node cells in this specific graft-vs-host assay

  17. The slow cell death response when screening chemotherapeutic agents.

    Science.gov (United States)

    Blois, Joseph; Smith, Adam; Josephson, Lee

    2011-09-01

    To examine the correlation between cell death and a common surrogate of death used in screening assays, we compared cell death responses to those obtained with the sulforhodamine B (SRB) cell protein-based "cytotoxicity" assay. With the SRB assay, the Hill equation was used to obtain an IC50 and final cell mass, or cell mass present at infinite agent concentrations, with eight adherent cell lines and four agents (32 agent/cell combinations). Cells were treated with high agent concentrations (well above the SRB IC50) and the death response determined as the time-dependent decrease in cells failing to bind both annexin V and vital fluorochromes by flow cytometry. Death kinetics were categorized as fast (5/32) (similar to the reference nonadherent Jurkat line), slow (17/32), or none (10/32), despite positive responses in the SRB assay in all cases. With slow cell death, a single exposure to a chemotherapeutic agent caused a slow, progressive increase in dead (necrotic) and dying (apoptotic) cells for at least 72 h. Cell death (defined by annexin and/or fluorochrome binding) did not correlate with the standard SRB "cytotoxicity" assay. With the slow cell death response, a single exposure to an agent caused a slow conversion from vital to apoptotic and necrotic cells over at least 72 h (the longest time point examined). Here, increasing the time of exposure to agent concentrations modestly above the SRB IC50 provides a method of maximizing cell kill. If tumors respond similarly, sustained low doses of chemotherapeutic agents, rather than a log-kill, maximum tolerated dose strategy may be an optimal strategy of maximizing tumor cell death.

  18. System-wide Analysis of the T Cell Response

    Directory of Open Access Journals (Sweden)

    Ruxandra Covacu

    2016-03-01

    Full Text Available The T cell receptor (TCR controls the cellular adaptive immune response to antigens, but our understanding of TCR repertoire diversity and response to challenge is still incomplete. For example, TCR clones shared by different individuals with minimal alteration to germline gene sequences (public clones are detectable in all vertebrates, but their significance is unknown. Although small in size, the zebrafish TCR repertoire is controlled by processes similar to those operating in mammals. Thus, we studied the zebrafish TCR repertoire and its response to stimulation with self and foreign antigens. We found that cross-reactive public TCRs dominate the T cell response, endowing a limited TCR repertoire with the ability to cope with diverse antigenic challenges. These features of vertebrate public TCRs might provide a mechanism for the rapid generation of protective T cell immunity, allowing a short temporal window for the development of more specific private T cell responses.

  19. The effect of incorporation of SDF-1alpha into PLGA scaffolds on stem cell recruitment and the inflammatory response.

    Science.gov (United States)

    Thevenot, Paul T; Nair, Ashwin M; Shen, Jinhui; Lotfi, Parisa; Ko, Cheng-Yu; Tang, Liping

    2010-05-01

    Despite significant advances in the understanding of tissue responses to biomaterials, most implants are still plagued by inflammatory responses which can lead to fibrotic encapsulation. This is of dire consequence in tissue engineering, where seeded cells and bioactive components are separated from the native tissue, limiting the regenerative potential of the design. Additionally, these interactions prevent desired tissue integration and angiogenesis, preventing functionality of the design. Recent evidence supports that mesenchymal stem cells (MSC) and hematopoietic stem cells (HSC) can have beneficial effects which alter the inflammatory responses and improve healing. The purpose of this study was to examine whether stem cells could be targeted to the site of biomaterial implantation and whether increasing local stem cell responses could improve the tissue response to PLGA scaffold implants. Through incorporation of SDF-1alpha through factor adsorption and mini-osmotic pump delivery, the host-derived stem cell response can be improved resulting in 3X increase in stem cell populations at the interface for up to 2 weeks. These interactions were found to significantly alter the acute mast cell responses, reducing the number of mast cells and degranulated mast cells near the scaffold implants. This led to subsequent downstream reduction in the inflammatory cell responses, and through altered mast cell activation and stem cell participation, increased angiogenesis and decreased fibrotic responses to the scaffold implants. These results support that enhanced recruitment of autologous stem cells can improve the tissue responses to biomaterial implants through modifying/bypassing inflammatory cell responses and jumpstarting stem cell participation in healing at the implant interface. Copyright 2010 Elsevier Ltd. All rights reserved.

  20. Evidence for deterministic chaos in aperiodic oscillations of acute lymphoblastic leukemia cells in long-term culture

    Science.gov (United States)

    Lambrou, George I.; Chatziioannou, Aristotelis; Vlahopoulos, Spiros; Moschovi, Maria; Chrousos, George P.

    Biological systems are dynamic and possess properties that depend on two key elements: initial conditions and the response of the system over time. Conceptualizing this on tumor models will influence conclusions drawn with regard to disease initiation and progression. Alterations in initial conditions dynamically reshape the properties of proliferating tumor cells. The present work aims to test the hypothesis of Wolfrom et al., that proliferation shows evidence for deterministic chaos in a manner such that subtle differences in the initial conditions give rise to non-linear response behavior of the system. Their hypothesis, tested on adherent Fao rat hepatoma cells, provides evidence that these cells manifest aperiodic oscillations in their proliferation rate. We have tested this hypothesis with some modifications to the proposed experimental setup. We have used the acute lymphoblastic leukemia cell line CCRF-CEM, as it provides an excellent substrate for modeling proliferation dynamics. Measurements were taken at time points varying from 24h to 48h, extending the assayed populations beyond that of previous published reports that dealt with the complex dynamic behavior of animal cell populations. We conducted flow cytometry studies to examine the apoptotic and necrotic rate of the system, as well as DNA content changes of the cells over time. The cells exhibited a proliferation rate of nonlinear nature, as this rate presented oscillatory behavior. The obtained data have been fit in known models of growth, such as logistic and Gompertzian growth.

  1. Mesenchymal stem cells induce dermal fibroblast responses to injury

    International Nuclear Information System (INIS)

    Smith, Andria N.; Willis, Elise; Chan, Vincent T.; Muffley, Lara A.; Isik, F. Frank; Gibran, Nicole S.; Hocking, Anne M.

    2010-01-01

    Although bone marrow-derived mesenchymal stem cells have been shown to promote repair when applied to cutaneous wounds, the mechanism for this response remains to be determined. The aim of this study was to determine the effects of paracrine signaling from mesenchymal stem cells on dermal fibroblast responses to injury including proliferation, migration and expression of genes important in wound repair. Dermal fibroblasts were co-cultured with bone marrow-derived mesenchymal stem cells grown in inserts, which allowed for paracrine interactions without direct cell contact. In this co-culture model, bone marrow-derived mesenchymal stem cells regulate dermal fibroblast proliferation, migration and gene expression. When co-cultured with mesenchymal stem cells, dermal fibroblasts show increased proliferation and accelerated migration in a scratch assay. A chemotaxis assay also demonstrated that dermal fibroblasts migrate towards bone marrow-derived mesenchymal stem cells. A PCR array was used to analyze the effect of mesenchymal stem cells on dermal fibroblast gene expression. In response to mesenchymal stem cells, dermal fibroblasts up-regulate integrin alpha 7 expression and down-regulate expression of ICAM1, VCAM1 and MMP11. These observations suggest that mesenchymal stem cells may provide an important early signal for dermal fibroblast responses to cutaneous injury.

  2. The radiation response of cells recovering after chronic hypoxia

    International Nuclear Information System (INIS)

    Kwok, T.T.; Sutherland, R.M.

    1989-01-01

    Experiments were performed to study the influence of hypoxic pretreatment on the radiation response of A431 human squamous carcinoma cells. Reaeration for 10 min after chronic hypoxia (greater than 2 h) was found to enhance the radiosensitivity of A431 cells, and the maximal effect was seen for those cells reaerated after 12 h of hypoxia. The radiosensitivity enhancement for reaerated cells after 12 h of hypoxia was maximized by 5 min after the return to aerobic conditions and reached the control level by 12 h of reaeration. This enhanced radiosensitive state was characterized by a reduced shoulder region and increased slope of the radiation dose-response curve for cells in both the exponential and plateau phases of growth. There was a slight increase in the number of G1 and decrease in the number of S and G2 + M cells for both exponential- and plateau-phase cultures following 12 h hypoxic treatment. Although growth inhibition induced by 12 h of hypoxia was seen for cells in the exponential phase, there was no cell number change in the plateau-phase culture after hypoxia. Plating efficiency (PE) of cells in both growth phases was reduced by 30% after hypoxia. Furthermore, in the exponential-phase culture, the extent of reduction in PE after hypoxia was similar among cells in different phases of the cell cycle. Although S-phase cells in exponentially growing cultures were relatively more resistant to radiation than G1 and G2 + M cells, the cell age-response pattern was the same whether the cells had been aerobic or hypoxic before reaeration and irradiation. Furthermore, the enhancement ratio associated with reaeration after 12 h of hypoxia for these three subpopulations of cells was 1.3. Our results indicate that the increase in radiosensitivity due to reaeration after chronic hypoxia is unlikely to be related to the changes of cell cycle stage and growth phase during hypoxic treatment

  3. The intersection between DNA damage response and cell death pathways.

    Science.gov (United States)

    Nowsheen, S; Yang, E S

    2012-10-01

    Apoptosis is a finely regulated process that serves to determine the fate of cells in response to various stresses. One such stress is DNA damage, which not only can signal repair processes but is also intimately involved in regulating cell fate. In this review we examine the relationship between the DNA damage/repair response in cell survival and apoptosis following insults to the DNA. Elucidating these pathways and the crosstalk between them is of great importance, as they eventually contribute to the etiology of human disease such as cancer and may play key roles in determining therapeutic response. This article is part of a Special Issue entitled "Apoptosis: Four Decades Later".

  4. Epidermal stem cells response to radiative genotoxic stress

    International Nuclear Information System (INIS)

    Marie, Melanie

    2013-01-01

    Human skin is the first organ exposed to various environmental stresses, which requires the development by skin stem cells of specific mechanisms to protect themselves and to ensure tissue homeostasis. As stem cells are responsible for the maintenance of epidermis during individual lifetime, the preservation of genomic integrity in these cells is essential. My PhD aimed at exploring the mechanisms set up by epidermal stem cells in order to protect themselves from two genotoxic stresses, ionizing radiation (Gamma Rays) and ultraviolet radiation (UVB). To begin my PhD, I have taken part of the demonstration of protective mechanisms used by keratinocyte stem cells after ionizing radiation. It has been shown that these cells are able to rapidly repair most types of radiation-induced DNA damage. Furthermore, we demonstrated that this repair is activated by the fibroblast growth factor 2 (FGF2). In order to know if this protective mechanism is also operating in cutaneous carcinoma stem cells, we investigated the response to gamma Rays of carcinoma stem cells isolated from a human carcinoma cell line. As in normal keratinocyte stem cells, we demonstrated that cancer stem cells could rapidly repair radio-induced DNA damage. Furthermore, fibroblast growth factor 2 also mediates this repair, notably thanks to its nuclear isoforms. The second project of my PhD was to study human epidermal stem cells and progenitors responses to UVB radiation. Once cytometry and irradiation conditions were set up, the toxicity of UVB radiation has been evaluate in the primary cell model. We then characterized UVB photons effects on cell viability, proliferation and repair of DNA damage. This study allowed us to bring out that responses of stem cells and their progeny to UVB are different, notably at the level of part of their repair activity of DNA damage. Moreover, progenitors and stem cells transcriptomic responses after UVB irradiation have been study in order to analyze the global

  5. Epithelium-innate immune cell axis in mucosal responses to SIV.

    Science.gov (United States)

    Shang, L; Duan, L; Perkey, K E; Wietgrefe, S; Zupancic, M; Smith, A J; Southern, P J; Johnson, R P; Haase, A T

    2017-03-01

    In the SIV (simian immunodeficiency virus)-rhesus macaque model of HIV-1 (human immunodeficiency virus type I) transmission to women, one hallmark of the mucosal response to exposure to high doses of SIV is CD4 T-cell recruitment that fuels local virus expansion in early infection. In this study, we systematically analyzed the cellular events and chemoattractant profiles in cervical tissues that precede CD4 T-cell recruitment. We show that vaginal exposure to the SIV inoculum rapidly induces chemokine expression in cervical epithelium including CCL3, CCL20, and CXCL8. The chemokine expression is associated with early recruitment of macrophages and plasmacytoid dendritic cells that are co-clustered underneath the cervical epithelium. Production of chemokines CCL3 and CXCL8 by these cells in turn generates a chemokine gradient that is spatially correlated with the recruitment of CD4 T cells. We further show that the protection of SIVmac239Δnef vaccination against vaginal challenge is correlated with the absence of this epithelium-innate immune cell-CD4 T-cell axis response in the cervical mucosa. Our results reveal a critical role for cervical epithelium in initiating early mucosal responses to vaginal infection, highlight an important role for macrophages in target cell recruitment, and provide further evidence of a paradoxical dampening effect of a protective vaccine on these early mucosal responses.

  6. [Skin cell response after jellyfish sting].

    Science.gov (United States)

    Adamicová, Katarína; Výbohová, Desanka; Fetisovová, Želmíra; Nováková, Elena; Mellová, Yvetta

    2016-01-01

    Jellyfish burning is not commonly part of the professional finding in the central Europe health care laboratory. Holiday seaside tourism includes different and unusual presentations of diseases for our worklplaces. Sea water-sports and leisure is commonly connected with jellyfish burning and changes in the skin, that are not precisely described. Authors focused their research on detection of morphological and quantitative changes of some inflammatory cells in the skin biopsy of a 59-years-old woman ten days after a jellyfish stinging. Because of a comparison of findings the biopsy was performed in the skin with lesional and nonlesional skin. Both excisions of the skin were tested by imunohistochemical methods to detect CD68, CD163, CD30, CD4, CD3, CD8, CD20 a CD1a, to detect histiocytes, as well as several clones of lymphocytes and Langerhans cells (antigen presenting cells of skin), CD 117, toluidin blue and chloracetase esterase to detect mastocytes and neutrophils. Material was tested by immunofluorescent methods to detect IgA, IgM, IgG, C3, C4, albumin and fibrinogen. Representative view-fields were documented by microscope photocamera Leica DFC 420 C. Registered photos from both samples of the skin were processed by morphometrical analysis by the Vision Assistant software. A student t-test was used for statistical analysis of reached results. Mean values of individual found cells in the sample with lesion and without lesion were as follows: CD117 -2.64/0.37, CD68-6.86/1.63, CD163-3.13/2.23, CD30-1.36/0.02, CD4-3.51/0.32, CD8-8.22/0.50, CD3-10.69/0.66, CD20-0.56/0.66, CD1a-7.97/0.47 respectively. Generally mild elevation of eosinofils in lesional skin was detected. Increased values of tested cells seen in excision from lesional skin when compared with nonlesional ones were statistically significant in eight case at the level p = 0.033 to 0.001. A not statistically significant difference was found only in the group of CD163+ histiocytes. Authors detected numbers

  7. Chemotherapy and radiation therapy elicits tumor specific T cell responses in a breast cancer patient

    International Nuclear Information System (INIS)

    Bernal-Estévez, David; Sánchez, Ramiro; Tejada, Rafael E.; Parra-López, Carlos

    2016-01-01

    Experimental evidence and clinical studies in breast cancer suggest that some anti-tumor therapy regimens generate stimulation of the immune system that accounts for tumor clinical responses, however, demonstration of the immunostimulatory power of these therapies on cancer patients continues to be a formidable challenge. Here we present experimental evidence from a breast cancer patient with complete clinical response after 7 years, associated with responsiveness of tumor specific T cells. T cells were obtained before and after anti-tumor therapy from peripheral blood of a 63-years old woman diagnosed with ductal breast cancer (HER2/neu+++, ER-, PR-, HLA-A*02:01) treated with surgery, followed by paclitaxel, trastuzumab (suspended due to cardiac toxicity), and radiotherapy. We obtained a leukapheresis before surgery and after 8 months of treatment. Using in vitro cell cultures stimulated with autologous monocyte-derived dendritic cells (DCs) that produce high levels of IL-12, we characterize by flow cytometry the phenotype of tumor associated antigens (TAAs) HER2/neu and NY-ESO 1 specific T cells. The ex vivo analysis of the TCR-Vβ repertoire of TAA specific T cells in blood and Tumor Infiltrating Lymphocytes (TILs) were performed in order to correlate both repertoires prior and after therapy. We evidence a functional recovery of T cell responsiveness to polyclonal stimuli and expansion of TAAs specific CD8+ T cells using peptide pulsed DCs, with an increase of CTLA-4 and memory effector phenotype after anti-tumor therapy. The ex vivo analysis of the TCR-Vβ repertoire of TAA specific T cells in blood and TILs showed that whereas the TCR-Vβ04-02 clonotype is highly expressed in TILs the HER2/neu specific T cells are expressed mainly in blood after therapy, suggesting that this particular TCR was selectively enriched in blood after anti-tumor therapy. Our results show the benefits of anti-tumor therapy in a breast cancer patient with clinical complete response in

  8. PET/CT imaging in response evaluation of patients with small cell lung cancer

    DEFF Research Database (Denmark)

    Fischer, Barbara M; Mortensen, Jann; Langer, Seppo W

    2006-01-01

    UNLABELLED: There is an increasing amount of evidence on the usability of PET in response evaluation of non-small cell lung cancer. However, data on SCLC is scarce and mainly retrospective. This prospective study assesses the use of PET (positron emission tomography) and PET/CT in response...... evaluation of patients with small cell lung cancer (SCLC). METHODS: Assignment of early and final response was compared between PET, PET/CT, and CT in 20 patients with SCLC. Final response as assigned by CT (RECIST) served as reference. RESULTS: At response evaluation after one cycle of chemotherapy major...... by PET/CT is feasible, but it is uncertain whether it adds further information to evaluation by RECIST, thus further studies and standardization of methods are needed....

  9. iNKT cells suppress the CD8+ T cell response to a murine Burkitt's-like B cell lymphoma.

    Directory of Open Access Journals (Sweden)

    Ryan L Bjordahl

    Full Text Available The T cell response to B cell lymphomas differs from the majority of solid tumors in that the malignant cells themselves are derived from B lymphocytes, key players in immune response. B cell lymphomas are therefore well situated to manipulate their surrounding microenvironment to enhance tumor growth and minimize anti-tumor T cell responses. We analyzed the effect of T cells on the growth of a transplantable B cell lymphoma and found that iNKT cells suppressed the anti-tumor CD8(+ T cell response. Lymphoma cells transplanted into syngeneic wild type (WT mice or Jalpha18(-/- mice that specifically lack iNKT cells grew initially at the same rate, but only the mice lacking iNKT cells were able to reject the lymphoma. This effect was due to the enhanced activity of tumor-specific CD8(+ T cells in the absence of iNKT cells, and could be partially reversed by reconstitution of iNKT cells in Jalpha 18(-/- mice. Treatment of tumor-bearing WT mice with alpha -galactosyl ceramide, an activating ligand for iNKT cells, reduced the number of tumor-specific CD8(+ T cells. In contrast, lymphoma growth in CD1d1(-/- mice that lack both iNKT and type II NKT cells was similar to that in WT mice, suggesting that type II NKT cells are required for full activation of the anti-tumor immune response. This study reveals a tumor-promoting role for iNKT cells and suggests their capacity to inhibit the CD8(+ T cell response to B cell lymphoma by opposing the effects of type II NKT cells.

  10. Evidence of heterogeneity within bovine satellite cells isolated from young and adult animals.

    Science.gov (United States)

    Li, J; Gonzalez, J M; Walker, D K; Hersom, M J; Ealy, A D; Johnson, S E

    2011-06-01

    Satellite cells are a heterogeneous population of myogenic precursors responsible for muscle growth and repair in mammals. The objectives of the experiment were to examine the growth rates and degree of heterogeneity within bovine satellite cells (BSC) isolated from young and adult animals. The BSC were harvested from the semimembranosus of young (4.3 ± 0.5 d) and adult (estimated 24 to 27 mo) cattle and cultured en masse. Young animal BSC re-enter the cell cycle sooner and reach maximal 5-ethynyl-2'-deoxyuridine (EdU) incorporation earlier (P animals after 3, 4, and 5 d in culture. These results indicate that BSC from young animals activate, proliferate, and differentiate sooner than isolates from adult animals. Lineage heterogeneity within BSC was examined using antibodies specific for Pax7 and Myf5, lineage markers of satellite cells, and myoblasts. Immunocytochemistry revealed the majority of Pax7-expressing BSC also express Myf5; a minor population (~5%) fails to exhibit Myf5 immunoreactivity. The percentage of Pax7:Myf5 BSC from young animals decreases sooner (P cell clones were established and analyzed after 10 d. Colonies segregated into 2 groups based upon population doubling time. Immunostaining of the slow-growing colonies (population doubling time ≥ 3 d) revealed that a portion exhibited asymmetric distribution of the lineage markers Pax7 and Myf5, similar to self-renewable mouse muscle stem cells. In summary, these results offer insight into the heterogeneity of BSC and provide evidence for subtle differences between rodent and bovine myogenic precursors.

  11. Phenomenon of adaptive response of cells in radiobiology

    International Nuclear Information System (INIS)

    Fillipovich, I.V.

    1991-01-01

    Consideration is given to various adaptive reactions to low-level radiation, their association with an absorbed dose, dose rate, radiation quality and time-interval between exposures, as well as with a cell cycle phase. Possible mechanisms of the adaptive response and the character and role of DNA damages, that can induce gene expression of the adaptive response, are discussed. The data on the influence of a preliminary long-term exposure to low-level radiation on the radiosensitivity of biological objects are analyzed with due regard for the adaptive cell response. It is concluded that the adaptive response of cells to ionizing radiation is a particular case of the phenomenon of cell adaptation of the effect of genotoxic factors of the environment

  12. Evidence That Androgens Modulate Human Thymic T Cell Output

    Science.gov (United States)

    Olsen, Nancy J.; Kovacs, William J.

    2010-01-01

    Background The thymus has long been recognized as a target for the actions of androgenic hormones, but it has only been recently recognized that alterations in circulating levels of gonadal steroids might affect thymic output of T cells. We had the opportunity to examine parameters of thymic cellular output in several hypogonadal men undergoing androgen replacement therapy. Methods Circulating naive (CD4+CD45RA+) T cells were quantitated by flow cytometric analysis of peripheral blood mononuclear cells (PBMCs). Cells bearing T cell receptor excision circles (TRECs) were quantitated using real-time PCR amplification of DNA isolated from PBMCs from normal men and from hypogonadal men before and after testosterone replacement therapy. Results CD4+CD45+ (“naïve”) T cells comprised 10.5% of lymphocytes in normal males; this proportion was greatly increased in two hypogonadal men (35.5% and 44.4%). One man was studied sequentially during treatment with physiologic doses of testosterone. CD4+CD45RA+ cells fell from 37.36% to 20.05% after one month and to 12.51% after 7 months of normalized androgen levels. In two hypogonadal patients TREC levels fell by 83% and 78% after androgen replacement therapy. Conclusions Our observations indicate that the hypogonadal state is associated with increased thymic output of T cells and that this increase in recent thymic emigrants in peripheral blood is reversed by androgen replacement. PMID:21218609

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

    Science.gov (United States)

    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

    2015-09-01

    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.

  14. Suppression of pro-inflammatory T-cell responses by human mesothelial cells.

    Science.gov (United States)

    Lin, Chan-Yu; Kift-Morgan, Ann; Moser, Bernhard; Topley, Nicholas; Eberl, Matthias

    2013-07-01

    Human γδ T cells reactive to the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP) contribute to acute inflammatory responses. We have previously shown that peritoneal dialysis (PD)-associated infections with HMB-PP producing bacteria are characterized by locally elevated γδ T-cell frequencies and poorer clinical outcome compared with HMB-PP negative infections, implying that γδ T cells may be of diagnostic, prognostic and therapeutic value in acute disease. The regulation by local tissue cells of these potentially detrimental γδ T-cell responses remains to be investigated. Freshly isolated γδ or αβ T cells were cultured with primary mesothelial cells derived from omental tissue, or with mesothelial cell-conditioned medium. Stimulation of cytokine production and proliferation by peripheral T cells in response to HMB-PP or CD3/CD28 beads was assessed by flow cytometry. Resting mesothelial cells were potent suppressors of pro-inflammatory γδ T cells as well as CD4+ and CD8+ αβ T cells. The suppression of γδ T-cell responses was mediated through soluble factors released by primary mesothelial cells and could be counteracted by SB-431542, a selective inhibitor of TGF-β and activin signalling. Recombinant TGF-β1 but not activin-A mimicked the mesothelial cell-mediated suppression of γδ T-cell responses to HMB-PP. The present findings indicate an important regulatory function of mesothelial cells in the peritoneal cavity by dampening pro-inflammatory T-cell responses, which may help preserve the tissue integrity of the peritoneal membrane in the steady state and possibly during the resolution of acute inflammation.

  15. Nitric oxide mediated bystander responses induced by microbeam targeted cells

    International Nuclear Information System (INIS)

    Shao, C.; Prise, K.M.; Folkard, M.; Michael, B.D.

    2003-01-01

    Considerable evidence has recently been accumulated in support of the existence of a 'bystander effect', which cells having received no irradiation show biological consequences from their vicinal irradiated cells. The application of microbeams is providing new insights into the radiation-induced bystander effect. The present study found that when a fraction of radioresistant human glioblastoma cells were individually targeted with a precise number of helium ions generated from the Gray Cancer Institute Charged Particle Microbeam, micronucleus (MN) induction significantly exceeded the expected value that was calculated from the number of MN observed when all of the cells were targeted assuming no bystander effect occurring. Even when only a single cell within a population was hit by one helium ion, the MN induction in the population could be increased by 16%. These results provide direct evidence of radiation-induced bystander effect. Moreover, MN was effectively induced in the unirradiated primary human fibroblasts and glioblastoma cells either co-cultured with irradiated cells or treated with the medium harvested from irradiated cells, indicating a signal molecule was produced from the irradiated cells. However, when c-PTIO, a nitric oxide (NO)-specific scavenger, was present in the medium during and after irradiation until MN analysis, the production of MN in all of the above cases was reduced to low levels. Consequently, NO plays an important role in the radiation-induced bystander effect

  16. Responses of fibroblasts and glial cells to nanostructured platinum surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Pennisi, C P; Sevcencu, C; Yoshida, K [Center for Sensory-Motor Interaction (SMI), Aalborg University, Aalborg (Denmark); Dolatshahi-Pirouz, A; Foss, M; Larsen, A Nylandsted; Besenbacher, F [Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus (Denmark); Hansen, J Lundsgaard [Department of Physics and Astronomy, Aarhus University, Aarhus (Denmark); Zachar, V, E-mail: cpennisi@hst.aau.d [Laboratory for Stem Cell Research, Aalborg University (Denmark)

    2009-09-23

    The chronic performance of implantable neural prostheses is affected by the growth of encapsulation tissue onto the stimulation electrodes. Encapsulation is associated with activation of connective tissue cells at the electrode's metallic contacts, usually made of platinum. Since surface nanotopography can modulate the cellular responses to materials, the aim of the present work was to evaluate the 'in vitro' responses of connective tissue cells to platinum strictly by modulating its surface nanoroughness. Using molecular beam epitaxy combined with sputtering, we produced platinum nanostructured substrates consisting of irregularly distributed nanopyramids and investigated their effect on the proliferation, cytoskeletal organization and cellular morphology of primary fibroblasts and transformed glial cells. Cells were cultured on these substrates and their responses to surface roughness were studied. After one day in culture, the fibroblasts were more elongated and their cytoskeleton less mature when cultured on rough substrates. This effect increased as the roughness of the surface increased and was associated with reduced cell proliferation throughout the observation period (4 days). Morphological changes also occurred in glial cells, but they were triggered by a different roughness scale and did not affect cellular proliferation. In conclusion, surface nanotopography modulates the responses of fibroblasts and glial cells to platinum, which may be an important factor in optimizing the tissue response to implanted neural electrodes.

  17. Molecular mechanism of radioadaptive response: A cross-adaptive response for enhanced repair of DNA damage in adapted cells

    International Nuclear Information System (INIS)

    Takaji Ikushima

    1997-01-01

    The radioadaptive response (RAR) has been attributed to the induction of a repair mechanism by low doses of ionizing radiation, but the molecular nature of the mechanism is not yet elucidated. We have characterized RAR in a series of experiments in cultured Chinese hamster V79 cells. A 4-h interval is required for the full expression of RAR, which decays with the progression of cell proliferation. Treatments with inhibitors of poly(ADP-ribose) polymerase, protein- or RNA synthesis, and protein kinase C suppress the RAR expression. The RAR cross-reacts on clastogenic lesions induced by other physical and chemical DNA-damaging agents. The presence of newly synthesised proteins has been detected during the expression period. Experiments performed using single-cell gel electrophoresis provided more direct evidence for a faster and enhaced DNA repair rate in adapted cells. Here, using single-cell gel electrophoresis, a cross-adaptive response has been demonstrated for enhanced repair of DNA damage induced by neocarzinostatin in radio-adapted cells. (author)

  18. Cytokines and the Inception of CD8 T Cell Responses

    Science.gov (United States)

    Cox, Maureen A.; Harrington, Laurie E.; Zajac, Allan J.

    2011-01-01

    The activation and differentiation of CD8 T cells is a necessary first step that endows these cells with the phenotypic and functional properties required for the control of intracellular pathogens. The induction of the CD8 T cell responses typically results in the development of a massive overall population of effector cells, comprised of both highly functional but short-lived terminally differentiated cells, as well as a smaller subset of precursors that are predisposed to survive and transition into the memory T cell pool. In this article we discuss how inflammatory cytokines and IL-2 bias the initial response towards short-lived effector generation and also highlight the potential counterbalancing role of IL-21. PMID:21371940

  19. Radiation response of haematopoietic cell lines of human origin

    International Nuclear Information System (INIS)

    Lehnert, S.; Rybka, W.B.; Suissa, S.; Giambattisto, D.

    1986-01-01

    Six human haematopoietic cell lines, five of leukaemic origin, including cells with myeloid, lymphoid and undifferentiated phenotype have been studied with respect to radiation response. The intrinsic radio-sensitivity of the cells varied widely, the D 0 s ranging from 0.53 to 1.39 Gy. Five of the cell lines showed some capacity to accumulate sublethal damage; in three of these, enhanced survival was demonstrated in split-dose experiments. One cell line (HL-60) was anomalous in that although little accumulation of sublethal damage was demonstrable, survival was enhanced by fractionation of the dose. Five of the six cell lines studied were of leukaemic origin. The results support the belief that, in contrast to the almost constant radiosensitivity of normal haematopoietic cell progenitors, leukaemic cell progenitors may show a wide range of radiosensitivities. (author)

  20. Tissue specific heterogeneity in effector immune cell response

    Directory of Open Access Journals (Sweden)

    Saba eTufail

    2013-08-01

    Full Text Available Post pathogen invasion, migration of effector T-cell subsets to specific tissue locations is of prime importance for generation of robust immune response. Effector T cells are imprinted with distinct ‘homing codes’ (adhesion molecules and chemokine receptors during activation which regulate their targeted trafficking to specific tissues. Internal cues in the lymph node microenvironment along with external stimuli from food (vitamin A and sunlight (vitamin D3 prime dendritic cells, imprinting them to play centrestage in the induction of tissue tropism in effector T cells. B cells as well, in a manner similar to effector T cells, exhibit tissue tropic migration. In this review, we have focused on the factors regulating the generation and migration of effector T cells to various tissues alongwith giving an overview of tissue tropism in B cells.

  1. Cyperus scariosus Chloroform Fraction Inhibits T cell Responses in ...

    African Journals Online (AJOL)

    Erah

    CSC did not significantly (p < 0.01) suppress Th2 (IL-4) system. Conclusion: The findings from this investigation reveal that C. scariosus causes immunosuppression by inhibiting Th1 cytokines. Keywords: Cyperus scariosus; Immunosuppression; Humoral antibody titre; Cell-mediated immune response; CD 4+ T- helper cells ...

  2. T Cell Responses: Naive to Memory and Everything in Between

    Science.gov (United States)

    Pennock, Nathan D.; White, Jason T.; Cross, Eric W.; Cheney, Elizabeth E.; Tamburini, Beth A.; Kedl, Ross M.

    2013-01-01

    The authors describe the actions that take place in T cells because of their amazing capacity to proliferate and adopt functional roles aimed at clearing a host of an infectious agent. There is a drastic decline in the T cell population once the primary response is over and the infection is terminated. What remains afterward is a population of T…

  3. A response calculus for immobilized T cell receptor ligands

    DEFF Research Database (Denmark)

    Andersen, P S; Menné, C; Mariuzza, R A

    2001-01-01

    determine the level of T cell activation. When fitted to T cell responses against purified ligands immobilized on plastic surfaces, the 2D-affinity model adequately simulated changes in cellular activation as a result of varying ligand affinity and ligand density. These observations further demonstrated...

  4. Radiation adaptive response for the growth of cultured glial cells

    International Nuclear Information System (INIS)

    Suzuki, S.; Miura, Y.; Kano, M.; Toda, T.; Urano, S.

    2003-01-01

    Full text: To examine the molecular mechanism of radiation adaptive response (RAR) for the growth of cultured glial cells and to investigate the influence of aging on the response, glial cells were cultured from young and aged rats (1 month and 24 months old). RAR for the growth of glial cells conditioned with a low dose of X-rays and subsequently exposed to a high dose of X-rays was examined for cell number and BrdU incorporation. Involvement of the subcellular signaling pathway factors in RAR was investigated using their inhibitors, activators and mutated glial cells. RAR was observed in cells cultured from young rats, but was not in cells from aged rats. The inhibitors of protein kinase C (PKC) and DNA-dependent protein kinase (DNA-PK) or phosphatidylinositol 3-kinase (PI3K) suppressed RAR. The activators of PKC instead of low dose irradiation also caused RAR. Moreover, glial cells cultured from severe combined immunodeficiency (scid) mice (CB-17 scid) and ataxia-telangiectasia (AT) cells from AT patients showed no RAR. These results indicated that PKC, ATM, DNAPK and/or PI3K were involved in RAR for growth and BrdU incorporation of cultured glial cells and RAR decreased with aging. Proteomics data of glial cells exposed to severe stress of H 2 O 2 or X-rays also will be presented in the conference since little or no difference has not been observed with slight stress yet

  5. Numerical and functional responses of intestinal helminths in three rajid skates: evidence for competition between parasites?

    Science.gov (United States)

    Randhawa, Haseeb S

    2012-11-01

    Host-parasite interactions generally involve communities of parasites. Within these communities, species will co-exist and/or interact with one another in a manner either benefiting the species involved or to the detriment of one or more of the species. At the level of helminth infracommunities, evidence for intra- and inter-specific competition includes numerical responses, i.e. those regulating helminth intensity of infection, and functional responses, i.e. where the presence of competitors modifies the realised niche of infrapopulations. The objectives of this study are to assess the numerical and functional responses of helminths in infracommunities from 3 rajid skates using general linear models. Despite a lack of numerical responses, functional responses to intra- and inter-specific interactions were observed. A positive correlation between the number of individuals in an infrapopulation and its niche breadth (functional response) was observed for the tapeworms Pseudanthobothrium spp. and Echeneibothrium spp., in all their respective hosts, and for the nematode Pseudanisakis sp. in the little skate. Evidence for inter-specific competition includes niche shifts in Pseudanthobothrium purtoni (ex little skate) and Pseudanisakis sp. (ex thorny skate) in the presence of Pseudanisakis sp. and the tapeworm Grillotia sp., respectively. These results are consistent with other studies in providing evidence for competition between helminths of skates.

  6. Regulatory T Cells and Host Anti-CML Responses

    National Research Council Canada - National Science Library

    Wong, Jr, K. K

    2008-01-01

    CD4+CD25+FoxP-3+ regulatory T-cells (Tregs) suppress immune responses to "self" antigens, but also have been shown to suppress host anti-tumor responses in several human malignancies, including breast, gastrointestinal, and ovarian cancer...

  7. Modulation of Trypanosoma cruzi-specific T-cell responses after chemotherapy for chronic Chagas disease

    Directory of Open Access Journals (Sweden)

    María Cecilia Albareda

    2015-05-01

    Full Text Available The aim of this review is to describe the contributions of the knowledge of T-cell responses to the understanding of the physiopathology and the responsiveness to etiological treatment during the chronic phase of Chagas disease. T-helper (Th1 and interleukin (IL-10 Trypanosoma cruzi-specific T-cells have been linked to the asymptomatic phase or to severe clinical forms of the disease, respectively or vice versa, depending on the T. cruzi antigen source, the patient’s location and the performed immunological assays. Parasite-specific T-cell responses are modulated after benznidazole (BZ treatment in chronically T. cruzi-infected subjects in association with a significant decrease in T. cruzi-specific antibodies. Accumulating evidence has indicated that treatment efficacy during experimental infection with T. cruzi results from the combined action of BZ and the activation of appropriate immune responses in the host. However, strong support of this interaction in T. cruzi-infected humans remains lacking. Overall, the quality of T-cell responses might be a key factor in not only disease evolution, but also chemotherapy responsiveness. Immunological parameters are potential indicators of treatment response regardless of achievement of cure. Providing tools to monitor and provide early predictions of treatment success will allow the development of new therapeutic options.

  8. Contribution of herpesvirus specific CD8 T cells to anti-viral T cell response in humans.

    Directory of Open Access Journals (Sweden)

    Elena Sandalova

    Full Text Available Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 12 with Dengue, 12 with Influenza, 3 with Adenovirus infection and 3 with fevers of unknown etiology. Virus-specific (EBV, HCMV, Influenza pentamer+ and total CD8 T cells were analyzed for activation (CD38/HLA-DR, proliferation (Ki-67/Bcl-2(low and cytokine production. We observed that all acute viral infections trigger an expansion of activated/proliferating CD8 T cells, which differs in size depending on the infection but is invariably inflated by CD8 T cells specific for persistent herpesviruses (HCMV/EBV. CD8 T cells specific for other non-related non persistent viral infection (i.e. Influenza were not activated. IL-15, which is produced during acute viral infections, is the likely contributing mechanism driving the selective activation of herpesvirus specific CD8 T cells. In addition we were able to show that herpesvirus specific CD8 T cells displayed an increased ability to produce the anti-viral cytokine interferon-gamma during the acute phase of heterologous viral infection. Taken together, these data demonstrated that activated herpesvirus specific CD8 T cells inflate the activated/proliferating CD8 T cells population present during acute viral infections in human and can contribute to the heterologous anti-viral T cell response.

  9. Epithelial cells from smokers modify dendritic cell responses in the context of influenza infection

    Science.gov (United States)

    Epidemiologic evidence suggests that cigarette smoking is a risk factor for infection with influenza, but the mechanisms underlying this susceptibility remain unknown. To ascertain if airway epithelial cells from smokers demonstrate a decreased ability to orchestrate an influenza...

  10. Natural killer cells promote early CD8 T cell responses against cytomegalovirus.

    Directory of Open Access Journals (Sweden)

    Scott H Robbins

    2007-08-01

    Full Text Available Understanding the mechanisms that help promote protective immune responses to pathogens is a major challenge in biomedical research and an important goal for the design of innovative therapeutic or vaccination strategies. While natural killer (NK cells can directly contribute to the control of viral replication, whether, and how, they may help orchestrate global antiviral defense is largely unknown. To address this question, we took advantage of the well-defined molecular interactions involved in the recognition of mouse cytomegalovirus (MCMV by NK cells. By using congenic or mutant mice and wild-type versus genetically engineered viruses, we examined the consequences on antiviral CD8 T cell responses of specific defects in the ability of the NK cells to control MCMV. This system allowed us to demonstrate, to our knowledge for the first time, that NK cells accelerate CD8 T cell responses against a viral infection in vivo. Moreover, we identify the underlying mechanism as the ability of NK cells to limit IFN-alpha/beta production to levels not immunosuppressive to the host. This is achieved through the early control of cytomegalovirus, which dramatically reduces the activation of plasmacytoid dendritic cells (pDCs for cytokine production, preserves the conventional dendritic cell (cDC compartment, and accelerates antiviral CD8 T cell responses. Conversely, exogenous IFN-alpha administration in resistant animals ablates cDCs and delays CD8 T cell activation in the face of NK cell control of viral replication. Collectively, our data demonstrate that the ability of NK cells to respond very early to cytomegalovirus infection critically contributes to balance the intensity of other innate immune responses, which dampens early immunopathology and promotes optimal initiation of antiviral CD8 T cell responses. Thus, the extent to which NK cell responses benefit the host goes beyond their direct antiviral effects and extends to the prevention of innate

  11. Modulation of immune response by alloactivated suppressor T cells

    International Nuclear Information System (INIS)

    Bernstein, A.; Sopori, M.L.; Gose, J.E.; Sondel, P.M.

    1979-01-01

    These studies show that there may be several different kinds of suppressor cells, each activated by different pathways and able to suppress different parts of the immune response either specifically or nonspecifically. As such, the physiology of one type of suppressor cell need not necessarily apply to that of another type of suppressor. Thus we emphasize the trap that the suppressor cell option provides: that is, virtually any previously inexplicable in vitro and in vivo immune phenomenon can always be adequately accounted for by evoking a suppressor mechanism, either by suppressing the response or suppressing the suppressor

  12. Phagocytic response of astrocytes to damaged neighboring cells.

    Directory of Open Access Journals (Sweden)

    Nicole M Wakida

    Full Text Available This study aims to understand the phagocytic response of astrocytes to the injury of neurons or other astrocytes at the single cell level. Laser nanosurgery was used to damage individual cells in both primary mouse cortical astrocytes and an established astrocyte cell line. In both cases, the release of material/substances from laser-irradiated astrocytes or neurons induced a phagocytic response in near-by astrocytes. Propidium iodide stained DNA originating from irradiated cells was visible in vesicles of neighboring cells, confirming phagocytosis of material from damaged cortical cells. In the presence of an intracellular pH indicator dye, newly formed vesicles correspond to acidic pH fluorescence, thus suggesting lysosome bound degradation of cellular debris. Cells with shared membrane connections prior to laser damage had a significantly higher frequency of induced phagocytosis compared to isolated cells with no shared membrane. The increase in phagocytic response of cells with a shared membrane occurred regardless of the extent of shared membrane (a thin filopodial connection vs. a cell cluster with significant shared membrane. In addition to the presence (or lack of a membrane connection, variation in phagocytic ability was also observed with differences in injury location within the cell and distance separating isolated astrocytes. These results demonstrate the ability of an astrocyte to respond to the damage of a single cell, be it another astrocyte, or a neuron. This single-cell level of analysis results in a better understanding of the role of astrocytes to maintain homeostasis in the CNS, particularly in the sensing and removal of debris in damaged or pathologic nervous tissue.

  13. Polyfunctional response by ImmTAC (IMCgp100) redirected CD8+ and CD4+ T cells.

    Science.gov (United States)

    Boudousquie, Caroline; Bossi, Giovanna; Hurst, Jacob M; Rygiel, Karolina A; Jakobsen, Bent K; Hassan, Namir J

    2017-11-01

    The success of immune system-based cancer therapies depends on a broad immune response engaging a range of effector cells and mechanisms. Immune mobilizing monoclonal T cell receptors (TCRs) against cancer (ImmTAC™ molecules: fusion proteins consisting of a soluble, affinity enhanced TCR and an anti-CD3 scFv antibody) were previously shown to redirect CD8 + and CD4 + T cells against tumours. Here we present evidence that IMCgp100 (ImmTAC recognizing a peptide derived from the melanoma-specific protein, gp100, presented by HLA-A*0201) efficiently redirects and activates effector and memory cells from both CD8 + and CD4 + repertoires. Using isolated subpopulations of T cells, we find that both terminally differentiated and effector memory CD8 + T cells redirected by IMCgp100 are potent killers of melanoma cells. Furthermore, CD4 + effector memory T cells elicit potent cytotoxic activity leading to melanoma cell killing upon redirection by IMCgp100. The majority of T cell subsets belonging to both the CD8 + and CD4 + repertoires secrete key pro-inflammatory cytokines (tumour necrosis factor-α, interferon-γ, interleukin-6) and chemokines (macrophage inflammatory protein-1α-β, interferon-γ-inducible protein-10, monocyte chemoattractant protein-1). At an individual cell level, IMCgp100-redirected T cells display a polyfunctional phenotype, which is a hallmark of a potent anti-cancer response. This study demonstrates that IMCgp100 induces broad immune responses that extend beyond the induction of CD8 + T cell-mediated cytotoxicity. These findings are of particular importance because IMCgp100 is currently undergoing clinical trials as a single agent or in combination with check point inhibitors for patients with malignant melanoma. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

  14. Reshaping Child Welfare's Response to Trauma: Assessment, Evidence-Based Intervention, and New Research Perspectives

    Science.gov (United States)

    Ai, Amy L.; Jackson Foster, Lovie J.; Pecora, Peter J.; Delaney, Nancy; Rodriguez, Wenceslao

    2013-01-01

    Growing evidence has linked early trauma with severe psychiatric consequences. Posttraumatic stress disorder (PTSD) is a potentially debilitating mental health condition found among some youth in foster care and foster care alumni. However, the current child welfare practice response has not met the demands in both assessment and intervention.…

  15. Studies on adaptive responses in Chinese hamster cells

    International Nuclear Information System (INIS)

    Michelin, S.C.; Perez, M.R. Del; Dubner, D.; Gisone, P.A.

    1997-01-01

    For many years the possibility has been considered of low doses of radiation inducing adaptive responses in cells and organisms against the mutagenic effects of radiation. Currently, a number of experimental data appraise the existence of an adaptive response that is characterized by a decrease of radiation induced genetic damages. The understanding of the molecular mechanism involved in this phenomenon permits to estimate the effects and risks of low dose exposure. In this work, preliminary results of studies on the induction of adaptive response in cells subjected to different doses of ionizing radiation are presented

  16. Antitumor Responses of Invariant Natural Killer T Cells

    Directory of Open Access Journals (Sweden)

    Jennie B. Altman

    2015-01-01

    Full Text Available Natural killer T (NKT cells are innate-like lymphocytes that were first described in the late 1980s. Since their initial description, numerous studies have collectively shed light on their development and effector function. These studies have highlighted the unique requirements for the activation of these lymphocytes and the functional responses that distinguish these cells from other effector lymphocyte populations such as conventional T cells and NK cells. This body of literature suggests that NKT cells play diverse nonredundant roles in a number of disease processes, including the initiation and propagation of airway hyperreactivity, protection against a variety of pathogens, development of autoimmunity, and mediation of allograft responses. In this review, however, we focus on the role of a specific lineage of NKT cells in antitumor immunity. Specifically, we describe the development of invariant NKT (iNKT cells and the factors that are critical for their acquisition of effector function. Next, we delineate the mechanisms by which iNKT cells influence and modulate the activity of other immune cells to directly or indirectly affect tumor growth. Finally, we review the successes and failures of clinical trials employing iNKT cell-based immunotherapies and explore the future prospects for the use of such strategies.

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

    Directory of Open Access Journals (Sweden)

    Neelkamal Chaudhary

    2010-02-01

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

  18. Nanosecond electric pulses trigger actin responses in plant cells

    International Nuclear Information System (INIS)

    Berghoefer, Thomas; Eing, Christian; Flickinger, Bianca; Hohenberger, Petra; Wegner, Lars H.; Frey, Wolfgang; Nick, Peter

    2009-01-01

    We have analyzed the cellular effects of nanosecond pulsed electrical fields on plant cells using fluorescently tagged marker lines in the tobacco cell line BY-2 and confocal laser scanning microscopy. We observe a disintegration of the cytoskeleton in the cell cortex, followed by contraction of actin filaments towards the nucleus, and disintegration of the nuclear envelope. These responses are accompanied by irreversible permeabilization of the plasma membrane manifest as uptake of Trypan Blue. By pretreatment with the actin-stabilizing drug phalloidin, the detachment of transvacuolar actin from the cell periphery can be suppressed, and this treatment can also suppress the irreversible perforation of the plasma membrane. We discuss these findings in terms of a model, where nanosecond pulsed electric fields trigger actin responses that are key events in the plant-specific form of programmed cell death.

  19. Characterisation of endogenous A2A and A2B receptor-mediated cyclic AMP responses in HEK 293 cells using the GloSensor™ biosensor: Evidence for an allosteric mechanism of action for the A2B-selective antagonist PSB 603.

    Science.gov (United States)

    Goulding, Joelle; May, Lauren T; Hill, Stephen J

    2018-01-01

    Endogenous adenosine A 2B receptors (A 2B AR) mediate cAMP accumulation in HEK 293 cells. Here we have used a biosensor to investigate the mechanism of action of the A 2B AR antagonist PSB 603 in HEK 293 cells. The A 2A agonist CGS 21680 elicited a small response in these cells (circa 20% of that obtained with NECA), suggesting that they also contain a small population of A 2A receptors. The responses to NECA and adenosine were antagonised by PSB 603, but not by the selective A 2A AR antagonist SCH 58261. In contrast, CGS 21680 responses were not antagonised by high concentrations of PSB 603, but were sensitive to inhibition by SCH 58261. Analysis of the effect of increasing concentrations of PSB 603 on the response to NECA indicated a non-competitive mode of action yielding a marked reduction in the NECA E MAX with no significant effect on EC 50 values. Kinetics analysis of the effect of PSB 603 on the A 2B AR-mediated NECA responses confirmed a saturable effect that was consistent with an allosteric mode of antagonism. The possibility that PSB 603 acts as a negative allosteric modulator of A 2B AR suggests new approaches to the development of therapeutic agents to treat conditions where adenosine levels are high. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  20. Immunotherapeutic strategies targeting Natural killer T cell responses in cancer

    Science.gov (United States)

    Shissler, Susannah C.; Bollino, Dominique R.; Tiper, Irina V.; Bates, Joshua; Derakhshandeh, Roshanak; Webb, Tonya J.

    2017-01-01

    Natural killer T (NKT) cells are a unique subset of lymphocytes that bridge the innate and adaptive immune system. NKT cells possess a classic αβ T-cell receptor (TCR) that is able to recognize self and foreign glycolipid antigens presented by the nonclassical class I major histocompatibility complex (MHC) molecule, CD1d. Type I NKT cells (referred to as invariant NKT cells) express a semi-invariant Vα14Jα18 TCR in mice and Vα24Jα18 TCR in humans. Type II NKT cells are CD1d-restricted T cells that express a more diverse set of TCR α chains. The two types of NKT cells often exert opposing effects especially in tumor immunity, where Type II cells generally suppress tumor immunity while Type I NKT cells can enhance antitumor immune responses. In this review, we focus on the role of NKT cells in cancer. We discuss their effector and suppressive functions, as well as describe preclinical and clinical studies utilizing therapeutic strategies focused on harnessing their potent anti-tumor effector functions, and conclude with a discussion on potential next steps for the utilization of NKT cell targeted therapies for the treatment of cancer. PMID:27393665

  1. Expanded breadth of the T-cell response to mosaic HIV-1 envelope DNA vaccination

    Energy Technology Data Exchange (ETDEWEB)

    Korber, Bette [Los Alamos National Laboratory; Fischer, William [Los Alamos National Laboratory; Wallstrom, Timothy [Los Alamos National Laboratory

    2009-01-01

    An effective AIDS vaccine must control highly diverse circulating strains of HIV-1. Among HIV -I gene products, the envelope (Env) protein contains variable as well as conserved regions. In this report, an informatic approach to the design of T-cell vaccines directed to HIV -I Env M group global sequences was tested. Synthetic Env antigens were designed to express mosaics that maximize the inclusion of common potential Tcell epitope (PTE) 9-mers and minimize the inclusion of rare epitopes likely to elicit strain-specific responses. DNA vaccines were evaluated using intracellular cytokine staining (ICS) in inbred mice with a standardized panel of highly conserved 15-mer PTE peptides. I, 2 and 3 mosaic sets were developed that increased theoretical epitope coverage. The breadth and magnitude ofT-cell immunity stimulated by these vaccines were compared to natural strain Env's; additional comparisons were performed on mutant Env's, including gpl60 or gpl45 with or without V regions and gp41 deletions. Among them, the 2 or 3 mosaic Env sets elicited the optimal CD4 and CD8 responses. These responses were most evident in CD8 T cells; the 3 mosaic set elicited responses to an average of 8 peptide pools compared to 2 pools for a set of3 natural Env's. Synthetic mosaic HIV -I antigens can therefore induce T-cell responses with expanded breadth and may facilitate the development of effective T -cell-based HIV -1 vaccines.

  2. Cell-cycle distributions and radiation responses of Chinese hamster cells cultured continuously under hypoxic conditions

    International Nuclear Information System (INIS)

    Tokita, N.; Carpenter, S.G.; Raju, M.R.

    1984-01-01

    Cell-cycle distributions were measured by flow cytometry for Chinese hamster (CHO) cells cultured continuously under hypoxic conditions. DNA histograms showed an accumulation of cells in the early S phase followed by a traverse delay through the S phase, and a G 2 block. During hypoxic culturing, cell viability decreased rapidly to less than 0.1% at 120 h. Radiation responses for cells cultured under these conditions showed an extreme radioresistance at 72 h. Results suggest that hypoxia induces a condition similar to cell synchrony which itself changes the radioresistance of hypoxic cells. (author)

  3. T-cell activation and early gene response in dogs.

    Directory of Open Access Journals (Sweden)

    Sally-Anne Mortlock

    Full Text Available T-cells play a crucial role in canine immunoregulation and defence against invading pathogens. Proliferation is fundamental to T-cell differentiation, homeostasis and immune response. Initiation of proliferation following receptor mediated stimuli requires a temporally programmed gene response that can be identified as immediate-early, mid- and late phases. The immediate-early response genes in T-cell activation engage the cell cycle machinery and promote subsequent gene activation events. Genes involved in this immediate-early response in dogs are yet to be identified. The present study was undertaken to characterise the early T-cell gene response in dogs to improve understanding of the genetic mechanisms regulating immune function. Gene expression profiles were characterised using canine gene expression microarrays and quantitative reverse transcription PCR (qRT-PCR, and paired samples from eleven dogs. Significant functional annotation clusters were identified following stimulation with phytohemagluttinin (PHA (5μg/ml, including the Toll-like receptor signaling pathway and phosphorylation pathways. Using strict statistical criteria, 13 individual genes were found to be differentially expressed, nine of which have ontologies that relate to proliferation and cell cycle control. These included, prostaglandin-endoperoxide synthase 2 (PTGS2/COX2, early growth response 1 (EGR1, growth arrest and DNA damage-inducible gene (GADD45B, phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1, V-FOS FBJ murine osteosarcoma viral oncogene homolog (FOS, early growth response 2 (EGR2, hemogen (HEMGN, polo-like kinase 2 (PLK2 and polo-like kinase 3 (PLK3. Differential gene expression was re-examined using qRT-PCR, which confirmed that EGR1, EGR2, PMAIP1, PTGS2, FOS and GADD45B were significantly upregulated in stimulated cells and ALAS2 downregulated. PTGS2 and EGR1 showed the highest levels of response in these dogs. Both of these genes are involved in

  4. Stem cell responses to plasma surface modified electrospun polyurethane scaffolds.

    Science.gov (United States)

    Zandén, Carl; Hellström Erkenstam, Nina; Padel, Thomas; Wittgenstein, Julia; Liu, Johan; Kuhn, H Georg

    2014-07-01

    The topographical effects from functional materials on stem cell behavior are currently of interest in tissue engineering and regenerative medicine. Here we investigate the influence of argon, oxygen, and hydrogen plasma surface modification of electrospun polyurethane fibers on human embryonic stem cell (hESC) and rat postnatal neural stem cell (NSC) responses. The plasma gases were found to induce three combinations of fiber surface functionalities and roughness textures. On randomly oriented fibers, plasma treatments lead to substantially increased hESC attachment and proliferation as compared to native fibers. Argon plasma was found to induce the most optimal combination of surface functionality and roughness for cell expansion. Contact guided migration of cells and alignment of cell processes were observed on aligned fibers. Neuronal differentiation around 5% was found for all samples and was not significantly affected by the induced variations of surface functional group distribution or individual fiber topography. In this study the influence of argon, oxygen, and hydrogen plasma surface modification of electrospun polyurethane fibers on human embryonic stem cell and rat postnatal neural stem cell (NSC) responses is studied with the goal of clarifying the potential effects of functional materials on stem cell behavior, a topic of substantial interest in tissue engineering and regenerative medicine. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Relation between radio-adaptive response and cell to cell communication

    International Nuclear Information System (INIS)

    Keiichiro Ishii

    1996-01-01

    Ionizing radiation has been considered to cause severe damages to DNA and do harm to cells in proportion to the dose, however low it might be. In 1984, Wolff et al. showed that human peripheral lymphocytes adapted to the low-dose radiation from 3 H-TdR added in culture medium and became resistant to the subsequent irradiation with high-doses of X-rays. This response, which is called radio-adaptive response, is also induced by X-rays and gamma-rays in human lymphocytes and Chinese hamster V79 cells. However, the mechanisms of and conditions for adaptive responses to radiation have not been clarified. With an objective of clarifying the conditions for adaptive responses of cells to radiation, we examined how the cell to cell communication is involved in the adaptive responses. We irradiated normal human embryo-derived (HE) cells and cancer cells (HeLa) in culture at high density with low-dose X-ray and examined their radio-adaptive responses by measuring the changes in sensitivity to subsequent high-dose X-ray irradiation using the Trypan Blue dye-exclusion test method. We also conducted experiments to examine the effects of Ca 2+ ions and Phorbol 12-Myristate 13-Acetate (TPA) which are supposed to be involved in cell to cell communication. (author)

  6. Some empirical evidence on the relationship between inventory management and social responsibility

    Directory of Open Access Journals (Sweden)

    Khaled Elsayed

    2013-09-01

    Full Text Available Despite the crucial role that inventory plays in supply chain management (SCM, research that examines the relationship between inventory and corporate social responsibility (CSR is rare. This is surprising given the evidence that inventory represents a huge source of cost, a matter that is often reported as a major impediment in practicing social responsibility in SCM. As such, this paper fills this gape in literature by examining directly the effect of inventory management on CSR. Maximum-likelihood ordered logistic regression was performed on a sample of 38 Egyptian listed firms during the period from 2007 to 2010. The results demonstrate that inventory management exerts a positive and significant coefficient on CSR. Further analysis shows that inventory management cannot be safely dropped from model of analysis. Rather, inventory management does add something unique in explaining differences in CSR. For practitioners interested in optimizing their firms’ values, thinking in managing supply chain imperatives, and specially inventory, in terms of social responsibility may guide them to build up a stock of reputational capital that can be used, in turn, to increase the cost of their rivals. This study, to the best of knowledge, is the first one that offers empirical evidence regarding the effect of inventory management on CSR. Moreover, the paper adds to both SCM and CSR literature by providing empirical evidence from Egypt as an emerging market, where much of the existing evidence reflects experience from developed countries.

  7. DNA damage responses in human induced pluripotent stem cells and embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Olga Momcilovic

    2010-10-01

    Full Text Available Induced pluripotent stem (iPS cells have the capability to undergo self-renewal and differentiation into all somatic cell types. Since they can be produced through somatic cell reprogramming, which uses a defined set of transcription factors, iPS cells represent important sources of patient-specific cells for clinical applications. However, before these cells can be used in therapeutic designs, it is essential to understand their genetic stability.Here, we describe DNA damage responses in human iPS cells. We observe hypersensitivity to DNA damaging agents resulting in rapid induction of apoptosis after γ-irradiation. Expression of pluripotency factors does not appear to be diminished after irradiation in iPS cells. Following irradiation, iPS cells activate checkpoint signaling, evidenced by phosphorylation of ATM, NBS1, CHEK2, and TP53, localization of ATM to the double strand breaks (DSB, and localization of TP53 to the nucleus of NANOG-positive cells. We demonstrate that iPS cells temporary arrest cell cycle progression in the G(2 phase of the cell cycle, displaying a lack of the G(1/S cell cycle arrest similar to human embryonic stem (ES cells. Furthermore, both cell types remove DSB within six hours of γ-irradiation, form RAD51 foci and exhibit sister chromatid exchanges suggesting homologous recombination repair. Finally, we report elevated expression of genes involved in DNA damage signaling, checkpoint function, and repair of various types of DNA lesions in ES and iPS cells relative to their differentiated counterparts.High degrees of similarity in DNA damage responses between ES and iPS cells were found. Even though reprogramming did not alter checkpoint signaling following DNA damage, dramatic changes in cell cycle structure, including a high percentage of cells in the S phase, increased radiosensitivity and loss of DNA damage-induced G(1/S cell cycle arrest, were observed in stem cells generated by induced pluripotency.

  8. Regulation of T Cell Homeostasis and Responses by Pten

    Directory of Open Access Journals (Sweden)

    Ryan H. Newton

    2012-06-01

    Full Text Available The generation of lipid products catalyzed by PI3K is critical for normal T cell homeostasis and a productive immune response. PI3K can be activated in response to antigen receptor, costimulatory, cytokine and chemokine signals. Moreover, dysregulation of this pathway frequently occurs in T cell lymphomas and is implicated in lymphoproliferative autoimmune disease. Akt acts as a central mediator of PI3K signals, downstream of which is the mTOR pathway, controlling cell growth and metabolism. Members of the Foxo family of transcription factors are also regulated by Akt, thus linking control over homing and migration of T cells, as well cell cycle entry, apoptosis, and DNA damage and oxidative stress responses, to PI3K signaling. PTEN, first identified as a tumor suppressor gene, encodes a lipid phosphatase that, by catalyzing the reverse of the PI3K reaction, directly opposes PI3K signaling. However, PTEN may have other functions as well, and recent reports have suggested roles for PTEN as a tumor suppressor independent of its effects on PI3K signaling. Through the use of models in which Pten is deleted specifically in T cells, it is becoming increasingly clear that control over autoimmunity and lymphomagenesis by PTEN involves multi-faceted functions of this molecule at multiple stages of T cell development.

  9. Exploring the representational basis of response-effect compatibility: Evidence from bilingual verbal response-effect mappings.

    Science.gov (United States)

    Földes, Noémi; Philipp, Andrea M; Badets, Arnaud; Koch, Iring

    2018-05-01

    The ideomotor principle states that actions are represented by their anticipated sensory effects. This notion is often tested using the response-effect compatibility (REC) paradigm, where participants' responses are followed either by a compatible or incompatible response effect (e.g., an effect on the right side after a right-hand response is considered R-E compatible due to the spatial overlap, whereas an effect on the left side after the right-hand response is considered incompatible). Shorter reaction times are typically observed in the compatible condition compared to the incompatible condition (i.e., REC effect), suggesting that effect anticipation plays a role in action control. Previous evidence from verbal REC suggested that effect anticipation can be due to conceptual R-E overlap, but there was also phonological overlap (i.e., anticipated reading of a word preceded by the vocal response of saying that very word). To examine the representational basis of REC, in three experiments, we introduced a bilingual R-E mapping to exclude phonological R-E overlap (i.e., in the R-E compatible condition, the translation equivalent of the response word is presented as an effect word in a different language). Our findings show that the REC effect is obtained when presenting the effect word in the same language as the response (i.e., monolingual condition), but the compatibility effect was not found when the semantically same word is presented in a different language, suggesting no conceptually generalized REC in a bilingual setting. (232 words). Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Radiation response of spermatogonial stem cells in the mouse

    International Nuclear Information System (INIS)

    Bootsma, A.L.

    1978-01-01

    Spermatogonial stem cells are able to repopulate the testis by forming clones that elongate along the walls of the seminiferous tubules depleted of spermatogenetic cells as a result of an irradiation. The surviving number of stem cells after irradiation was estimated by determining the fraction of repopulated tubules in cross-sections of the testis 11 weeks after irradiation. This fraction, called the 'repopulation index', is assumed to be directly proportional to the number of surviving stem cells. The response of spermatogonial stem cells in the CBA mouse to 1-MeV fission neutrons was investigated. Radioresistant, colony forming stem cells in the mouse testis move into a much more radiosensitive phase of their cell cycle shortly after irradiation. This is demonstrated in publication II in experiments in which total doses of 300 rad of neutrons and 1200 rad of X-rays were split into two equal fractions. The radiation response of spermatogonial stem cells in the mouse which survived various doses of fission neutrons 24 hours before was studied in publication III. Twenty four hours after a dose of 150 rad of fission neutrons all first-dose survivors have moved from a radioresistant (D 0 89+-4 rad in this study) towards a radiosensitive phase of their cell cycle. Spermatogonial stem cells which survive a neutron dose of 150 rad all belong to a radioresistant stem cell population in the seminiferous epithelium. The data in publication IV show that during the first 26 days after a dose of 150 rad of neutrons the stem cell population first increases and then slowly decreases its radiosensitivity, to stay fixed at a relatively high level. (Auth.)

  11. Biochemical and microscopic evidence for the internalization and degradation of heparin-containing mast cell granules by bovine endothelial cells

    International Nuclear Information System (INIS)

    Atkins, F.M.; Friedman, M.M.; Metcalfe, D.D.

    1985-01-01

    Incubation of [ 35 S]heparin-containing mast cell granules with cultured bovine endothelial cells was followed by the appearance of 35 S-granule-associated radioactivity within the endothelial cells and a decrease in radioactivity in the extracellular fluid. These changes occurred during the first 24 hours of incubation and suggested ingestion of the mast cell granules by the endothelial cells. Periodic electron microscopic examination of the monolayers confirmed this hypothesis by demonstrating apposition of the granules to the plasmalemma of endothelial cells, which was followed by the engulfment of the granules by cytoplasmic projections. Under light microscopic examination, mast cell granules within endothelial cells then appeared to undergo degradation. The degradation of [ 35 S]heparin in mast cell granules was demonstrated by a decrease in the amount of intracellular [ 35 S]heparin proteoglycan after 24 hours and the appearance of free [ 35 S]sulfate in the extracellular compartment. Intact endothelial cells were more efficient at degrading [ 35 S]heparin than were cell lysates or cell supernatants. These data provide evidence of the ability of endothelial cells to ingest mast cell granules and degrade native heparin that is presented as a part of the mast cell granule

  12. Effects of Behavioral Genetic Evidence on Perceptions of Criminal Responsibility and Appropriate Punishment

    Science.gov (United States)

    Appelbaum, Paul S.; Scurich, Nicholas; Raad, Raymond

    2015-01-01

    Demonstrations of a link between genetic variants and criminal behavior have stimulated increasing use of genetic evidence to reduce perceptions of defendants’ responsibility for criminal behavior and to mitigate punishment. However, because only limited data exist regarding the impact of such evidence on decision makers and the public at large, we recruited a representative sample of the U.S. adult population (n=960) for a web-based survey. Participants were presented with descriptions of three legal cases and were asked to: determine the length of incarceration for a convicted murderer; adjudicate an insanity defense; and decide whether a defendant should receive the death penalty. A fully crossed, between-participants, factorial design was used, varying the type of evidence (none, genetic, neuroimaging, both), heinousness of the crime, and past criminal record, with sentence or verdict as the primary outcome. Also assessed were participants’ apprehension of the defendant, belief in free will, political ideology, and genetic knowledge. Across all three cases, genetic evidence had no significant effects on outcomes. Neuroimaging data showed an inconsistent effect in one of the two cases in which it was introduced. In contrast, heinousness of the offense and past criminal record were strongly related to participants’ decisions. Moreover, participants’ beliefs about the controllability of criminal behavior and political orientations were significantly associated with their choices. Our findings suggest that neither hopes that genetic evidence will modify judgments of culpability and punishment nor fears about the impact of genetic evidence on decision makers are likely to come to fruition. PMID:26240516

  13. Effects of Behavioral Genetic Evidence on Perceptions of Criminal Responsibility and Appropriate Punishment.

    Science.gov (United States)

    Appelbaum, Paul S; Scurich, Nicholas; Raad, Raymond

    2015-05-01

    Demonstrations of a link between genetic variants and criminal behavior have stimulated increasing use of genetic evidence to reduce perceptions of defendants' responsibility for criminal behavior and to mitigate punishment. However, because only limited data exist regarding the impact of such evidence on decision makers and the public at large, we recruited a representative sample of the U.S. adult population (n=960) for a web-based survey. Participants were presented with descriptions of three legal cases and were asked to: determine the length of incarceration for a convicted murderer; adjudicate an insanity defense; and decide whether a defendant should receive the death penalty. A fully crossed, between-participants, factorial design was used, varying the type of evidence (none, genetic, neuroimaging, both), heinousness of the crime, and past criminal record, with sentence or verdict as the primary outcome. Also assessed were participants' apprehension of the defendant, belief in free will, political ideology, and genetic knowledge. Across all three cases, genetic evidence had no significant effects on outcomes. Neuroimaging data showed an inconsistent effect in one of the two cases in which it was introduced. In contrast, heinousness of the offense and past criminal record were strongly related to participants' decisions. Moreover, participants' beliefs about the controllability of criminal behavior and political orientations were significantly associated with their choices. Our findings suggest that neither hopes that genetic evidence will modify judgments of culpability and punishment nor fears about the impact of genetic evidence on decision makers are likely to come to fruition.

  14. The Inflammation Response to DEHP through PPARγ in Endometrial Cells

    Directory of Open Access Journals (Sweden)

    Qiansheng Huang

    2016-03-01

    Full Text Available Epidemiological studies have shown the possible link between phthalates and endometrium-related gynecological diseases, however the molecular mechanism(s behind this is/are still unclear. In the study, both primary cultured endometrial cells and an endometrial adenocarcinoma cell line (Ishikawa were recruited to investigate the effects of di-(2-ethylhexyl phthalate (DEHP at human-relevant concentrations. The results showed that DEHP did not affect the viability of either type of cell, which showed different responses to inflammation. Primary cultured cells showed stronger inflammatory reactions than the Ishikawa cell line. The expression of inflammatory factors was induced both at the mRNA and protein levels, however the inflammation did not induce the progress of epithelial-mesenchymal transition (EMT as the protein levels of EMT markers were not affected after exposure to either cell type. Further study showed that the mRNA levels of peroxisome proliferator-activated receptor gamma (PPARγ wereup-regulated after exposure. In all, our study showed that human-relevant concentrations of DEHP could elicit the inflammatory response in primary cultured endometrial cells rather than in Ishikawa cell line. PPARγ may act as the mediating receptor in the inflammation reaction.

  15. Th17 cell-mediated immune responses promote mast cell proliferation by triggering stem cell factor in keratinocytes

    International Nuclear Information System (INIS)

    Cho, Kyung-Ah; Park, Minhwa; Kim, Yu-Hee; Woo, So-Youn

    2017-01-01

    Although mast cells are traditionally thought to function as effector cells in allergic responses, they have increasingly been recognized as important regulators of various immune responses. Mast cells mature locally; thus, tissue-specific influences are important for promoting mast cell accumulation and survival in the skin and the gastrointestinal tract. In this study, we determined the effects of keratinocytes on mast cell accumulation during Th17-mediated skin inflammation. We observed increases in dermal mast cells in imiquimod-induced psoriatic dermatitis in mice accompanied by the expression of epidermal stem cell factor (SCF), a critical mast cell growth factor. Similar to mouse epidermal keratinocytes, SCF was highly expressed in the human HaCaT keratinocyte cell line following stimulation with IL−17. Further, keratinocytes promoted mast cell proliferation following stimulation with IL−17 in vitro. However, the effects of keratinocytes on mast cells were significantly diminished in the presence of anti−CD117 (stem cell factor receptor) blocking antibodies. Taken together, our results revealed that the Th17-mediated inflammatory environment promotes mast cell accumulation through keratinocyte-derived SCF. - Highlights: • Psoriasis-like skin inflammation increase dermal mast cells. • Keratinocyte produce stem cell factor in psoriasis-like skin inflammation. • Keratinocyte promote mast cell proliferation by stem cell factor dependent manner

  16. Increased proinflammatory responses from asthmatic human airway smooth muscle cells in response to rhinovirus infection

    Directory of Open Access Journals (Sweden)

    King Nicholas JC

    2006-05-01

    Full Text Available Abstract Background Exacerbations of asthma are associated with viral respiratory tract infections, of which rhinoviruses (RV are the predominant virus type. Airway smooth muscle is important in asthma pathogenesis, however little is known about the potential interaction of RV and human airway smooth muscle cells (HASM. We hypothesised that rhinovirus induction of inflammatory cytokine release from airway smooth muscle is augmented and differentially regulated in asthmatic compared to normal HASM cells. Methods HASM cells, isolated from either asthmatic or non-asthmatic subjects, were infected with rhinovirus. Cytokine production was assayed by ELISA, ICAM-1 cell surface expression was assessed by FACS, and the transcription regulation of IL-6 was measured by luciferase activity. Results RV-induced IL-6 release was significantly greater in HASM cells derived from asthmatic subjects compared to non-asthmatic subjects. This response was RV specific, as 5% serum- induced IL-6 release was not different in the two cell types. Whilst serum stimulated IL-8 production in cells from both subject groups, RV induced IL-8 production in only asthmatic derived HASM cells. The transcriptional induction of IL-6 was differentially regulated via C/EBP in the asthmatic and NF-κB + AP-1 in the non-asthmatic HASM cells. Conclusion This study demonstrates augmentation and differential transcriptional regulation of RV specific innate immune response in HASM cells derived from asthmatic and non-asthmatics, and may give valuable insight into the mechanisms of RV-induced asthma exacerbations.

  17. Spectral response of a polycrystalline silicon solar cell

    International Nuclear Information System (INIS)

    Ba, B.; Kane, M.

    1994-10-01

    A theoretical study of the spectral response of a polycrystalline silicon n-p junction solar cell is presented. The case of a fibrously oriented grain structure, involving grain boundary recombination velocity and grain size effects is discussed. The contribution of the base region on the internal quantum efficiency Q int is computed for different grain sizes and grain boundary recombination velocities in order to examine their influence. Suggestions are also made for the determination of base diffusion length in polycrystalline silicon solar cells using the spectral response method. (author). 15 refs, 4 figs

  18. Cell Wall Metabolism in Response to Abiotic Stress

    Science.gov (United States)

    Gall, Hyacinthe Le; Philippe, Florian; Domon, Jean-Marc; Gillet, Françoise; Pelloux, Jérôme; Rayon, Catherine

    2015-01-01

    This review focuses on the responses of the plant cell wall to several abiotic stresses including drought, flooding, heat, cold, salt, heavy metals, light, and air pollutants. The effects of stress on cell wall metabolism are discussed at the physiological (morphogenic), transcriptomic, proteomic and biochemical levels. The analysis of a large set of data shows that the plant response is highly complex. The overall effects of most abiotic stress are often dependent on the plant species, the genotype, the age of the plant, the timing of the stress application, and the intensity of this stress. This shows the difficulty of identifying a common pattern of stress response in cell wall architecture that could enable adaptation and/or resistance to abiotic stress. However, in most cases, two main mechanisms can be highlighted: (i) an increased level in xyloglucan endotransglucosylase/hydrolase (XTH) and expansin proteins, associated with an increase in the degree of rhamnogalacturonan I branching that maintains cell wall plasticity and (ii) an increased cell wall thickening by reinforcement of the secondary wall with hemicellulose and lignin deposition. Taken together, these results show the need to undertake large-scale analyses, using multidisciplinary approaches, to unravel the consequences of stress on the cell wall. This will help identify the key components that could be targeted to improve biomass production under stress conditions. PMID:27135320

  19. No evidence for the use of stem cell therapy for tendon disorders : a systematic review

    NARCIS (Netherlands)

    Pas, Haiko I M F L; Moen, Maarten H; Haisma, Hidde J; Winters, Marinus

    2017-01-01

    INTRODUCTION: Stem cells have emerged as a new treatment option for tendon disorders. We systematically reviewed the current evidence for stem cell therapy in tendon disorders. METHODS: Randomised and non-randomised controlled trials, cohort studies and case series with a minimum of 5 cases were

  20. A probabilistic approach for the interpretation of RNA profiles as cell type evidence

    NARCIS (Netherlands)

    de Zoete, J.; Curran, J.; Sjerps, M.

    2016-01-01

    DNA profiles can be used as evidence to distinguish between possible donors of a crime stain. In some cases, both the prosecution and the defence claim that the cell material was left by the suspect but they dispute which cell type was left behind. For example, in sexual offense cases the

  1. The response of human and rodent cells to hyperthermia

    International Nuclear Information System (INIS)

    Roizin-Towle, L.; Pirro, J.P.

    1991-01-01

    Inherent cellular radiosensitivity in vitro has been shown to be a good predictor of human tumor response in vivo. In contrast, the importance of the intrinsic thermosensitivity of normal and neoplastic human cells as a factor in the responsiveness of human tumors to adjuvant hyperthermia has never been analyzed systematically. A comparison of thermal sensitivity and thermo-radiosensitization in four rodent and eight human-derived cell lines was made in vitro. Arrhenius plots indicated that the rodent cells were more sensitive to heat killing than the human, and the break-point was 0.5 degrees C higher for the human than rodent cells. The relationship between thermal sensitivity and the interaction of heat with X rays at low doses was documented by thermal enhancement ratios (TER's). Cells received either a 1 hr exposure to 43 degrees C or a 20 minute treatment at 45 degrees C before exposure to 300 kVp X rays. Thermal enhancement ratios ranged from 1.0 to 2.7 for human cells heated at 43 degrees C and from 2.1 to 5.3 for heat exposures at 45 degrees C. Thermal enhancement ratios for rodent cells were generally 2 to 3 times higher than for human cells, because of the fact that the greater thermosensitivity of rodent cells results in a greater enhancement of radiation damage. Intrinsic thermosensitivity of human cells has relevance to the concept of thermal dose; intrinsic thermo-radiosensitization of a range of different tumor cells is useful in documenting the interactive effects of radiation combined with heat

  2. The Yin and Yang aspects of IL-27 in induction of cancer-specific T-cell responses and immunotherapy.

    Science.gov (United States)

    Li, Ming-Song; Liu, Zhenzhen; Liu, Jin-Qing; Zhu, Xiaotong; Liu, Zhihao; Bai, Xue-Feng

    2015-01-01

    Accumulating evidences from animal studies have indicated that both endogenous and exogenous IL-27, an IL-12 family of cytokine, can increase antitumor T-cell activities and inhibit tumor growth. IL-27 can modulate Treg responses, and program effector T cells into a unique T-effector stem cell (TSEC) phenotype, which enhances T-cell survival in the tumor microenvironment. However, animal studies also suggest that IL-27 induces molecular pathways such as IL-10, PD-L1 and CD39, which may downregulate tumor-specific T-cell responses. In this review paper, we will discuss the Yin and Yang aspects of IL-27 in the induction of tumor-specific T-cell responses, and the potential impacts of these functions of IL-27 in the design of cancer immunotherapy.

  3. Evidence Report: Risk of Crew Adverse Health Event Due to Altered Immune Response

    Science.gov (United States)

    Crucian, Brian; Sams, Clarence F.

    2013-01-01

    The Risk of Crew Adverse Health Event Due to Altered Immune Response is identified by the National Aeronautics and Space Administration (NASA) Human Research Program (HRP) as a recognized risk to human health and performance in space. The HRP Program Requirements Document (PRD) defines these risks. This Evidence Report provides a summary of the evidence that has been used to identify and characterize this risk. It is known that human immune function is altered in- and post-flight, but it is unclear at present if such alterations lead to increased susceptibility to disease. Reactivation of latent viruses has been documented in crewmembers, although this reactivation has not been directly correlated with immune changes or with observed diseases. As described in this report, further research is required to better characterize the relationships between altered immune response and susceptibility to disease during and after spaceflight. This is particularly important for future deep-space exploration missions.

  4. Biological response of cancer cells to radiation treatment

    Directory of Open Access Journals (Sweden)

    Rajamanickam eBaskar

    2014-11-01

    Full Text Available Cancer is a class of diseases characterized by uncontrolled cell growth and has the ability to spread or metastasize throughout the body. In recent years, remarkable progress has been made towards the understanding of proposed hallmarks of cancer development, care and treatment modalities. Radiation therapy or radiotherapy is an important and integral component of cancer management, mostly conferring a survival benefit. Radiation therapy destroys cancer by depositing high-energy radiation on the cancer tissues. Over the years, radiation therapy has been driven by constant technological advances and approximately 50% of all patients with localized malignant tumors are treated with radiation at some point in the course of their disease. In radiation oncology, research and development in the last three decades has led to considerable improvement in our understanding of the differential responses of normal and cancer cells. The biological effectiveness of radiation depends on the linear energy transfer (LET, total dose, number of fractions and radiosensitivity of the targeted cells or tissues. Radiation can either directly or indirectly (by producing free radicals damages the genome of the cell. This has been challenged in recent years by a newly identified phenomenon known as radiation induced bystander effect (RIBE. In RIBE, the non-irradiated cells adjacent to or located far from the irradiated cells/tissues demonstrate similar responses to that of the directly irradiated cells. Understanding the cancer cell responses during the fractions or after the course of irradiation will lead to improvements in therapeutic efficacy and potentially, benefitting a significant proportion of cancer patients. In this review, the clinical implications of radiation induced direct and bystander effects on the cancer cell are discussed.

  5. Anaplasma phagocytophilum and Anaplasma marginale Elicit Different Gene Expression Responses in Cultured Tick Cells

    Directory of Open Access Journals (Sweden)

    Zorica Zivkovic

    2009-01-01

    Full Text Available The genus Anaplasma (Rickettsiales: Anaplasmataceae includes obligate tick-transmitted intracellular organisms, Anaplasma phagocytophilum and Anaplasma marginale that multiply in both vertebrate and tick host cells. Recently, we showed that A. marginale affects the expression of tick genes that are involved in tick survival and pathogen infection and multiplication. However, the gene expression profile in A. phagocytophilum-infected tick cells is currently poorly characterized. The objectives of this study were to characterize tick gene expression profile in Ixodes scapularis ticks and cultured ISE6 cells in response to infection with A. phagocypthilum and to compare tick gene expression responses in A. phagocytophilum- and A. marginale-infected tick cells by microarray and real-time RT-PCR analyses. The results of these studies demonstrated modulation of tick gene expression by A. phagocytophilum and provided evidence of different gene expression responses in tick cells infected with A. phagocytophilum and A. marginale. These differences in Anaplasma-tick interactions may reflect differences in pathogen life cycle in the tick cells.

  6. Phenotypic and functional characterization of human memory T cell responses to Burkholderia pseudomallei.

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    Patcharaporn Tippayawat

    Full Text Available Infection with the Gram-negative bacterium Burkholderia pseudomallei is an important cause of community-acquired lethal sepsis in endemic regions in southeast Asia and northern Australia and is increasingly reported in other tropical areas. In animal models, production of interferon-gamma (IFN-gamma is critical for resistance, but in humans the characteristics of IFN-gamma production and the bacterial antigens that are recognized by the cell-mediated immune response have not been defined.Peripheral blood from 133 healthy individuals who lived in the endemic area and had no history of melioidosis, 60 patients who had recovered from melioidosis, and 31 other patient control subjects were stimulated by whole bacteria or purified bacterial proteins in vitro, and IFN-gamma responses were analyzed by ELISPOT and flow cytometry.B. pseudomallei was a potent activator of human peripheral blood NK cells for innate production of IFN-gamma. In addition, healthy individuals with serological evidence of exposure to B. pseudomallei and patients recovered from active melioidosis developed CD4(+ (and CD8(+ T cells that recognized whole bacteria and purified proteins LolC, OppA, and PotF, members of the B. pseudomallei ABC transporter family. This response was primarily mediated by terminally differentiated T cells of the effector-memory (T(EMRA phenotype and correlated with the titer of anti-B. pseudomallei antibodies in the serum.Individuals living in a melioidosis-endemic region show clear evidence of T cell priming for the ability to make IFN-gamma that correlates with their serological status. The ability to detect T cell responses to defined B. pseudomallei proteins in large numbers of individuals now provides the opportunity to screen candidate antigens for inclusion in protein or polysaccharide-conjugate subunit vaccines against this important but neglected disease.

  7. In vivo Ebola virus infection leads to a strong innate response in circulating immune cells.

    Science.gov (United States)

    Caballero, Ignacio S; Honko, Anna N; Gire, Stephen K; Winnicki, Sarah M; Melé, Marta; Gerhardinger, Chiara; Lin, Aaron E; Rinn, John L; Sabeti, Pardis C; Hensley, Lisa E; Connor, John H

    2016-09-05

    Ebola virus is the causative agent of a severe syndrome in humans with a fatality rate that can approach 90 %. During infection, the host immune response is thought to become dysregulated, but the mechanisms through which this happens are not entirely understood. In this study, we analyze RNA sequencing data to determine the host response to Ebola virus infection in circulating immune cells. Approximately half of the 100 genes with the strongest early increases in expression were interferon-stimulated genes, such as ISG15, OAS1, IFIT2, HERC5, MX1 and DHX58. Other highly upregulated genes included cytokines CXCL11, CCL7, IL2RA, IL2R1, IL15RA, and CSF2RB, which have not been previously reported to change during Ebola virus infection. Comparing this response in two different models of exposure (intramuscular and aerosol) revealed a similar signature of infection. The strong innate response in the aerosol model was seen not only in circulating cells, but also in primary and secondary target tissues. Conversely, the innate immune response of vaccinated macaques was almost non-existent. This suggests that the innate response is a major aspect of the cellular response to Ebola virus infection in multiple tissues. Ebola virus causes a severe infection in humans that is associated with high mortality. The host immune response to virus infection is thought to be an important aspect leading to severe pathology, but the components of this overactive response are not well characterized. Here, we analyzed how circulating immune cells respond to the virus and found that there is a strong innate response dependent on active virus replication. This finding is in stark contrast to in vitro evidence showing a suppression of innate immune signaling, and it suggests that the strong innate response we observe in infected animals may be an important contributor to pathogenesis.

  8. Reply to “Response: Board Composition and Firm Performance: Evidence from Bangladesh - A Sceptical View”

    Directory of Open Access Journals (Sweden)

    Afzalur Rashid

    2012-09-01

    Full Text Available This paper replies to Chowdhury’s (2010 response to the paper "Board Composition and Firm Performance: Evidence from Bangladesh" (2010. It challenges the strength of the criticisms, arguing that the factors discussed in Chowdhury (2010 do not necessarily impair the outcome of the research. The authors elucidate issues raised, and in so doing, reproduce the results incorporating the commentator’s suggestions.

  9. Responses of macaque ganglion cells to far violet lights

    International Nuclear Information System (INIS)

    De Monasterio, F.M.; Gouras, P.

    1977-01-01

    In a sample of 487 colour-opponent ganglion cells recorded in the central retina of the rhesus and cynomolgus monkeys, 9% of these neurones were found to have responses with the same sign at both ends of the visible spectrum mediated by red-sensitive cones and mid-spectral responses of opposite sign mediated by green-sensitive cones. Selective chromatic adaptation showed that the responses to far violet lights (400 to 420 nm) were due to input from red- and not blue-sensitive cones. These responses were enhanced by backgrounds depressing the sensitivity of blue- and green-sensitive cones and they were depressed by backgrounds depressing the sensitivity of red-sensitive cones; the sensitivity of these responses was yoked to that of responses to far red lights. The relative incidence of these ganglion cells was maximal at the foveal region and decreased towards the peripheral retina. The properties of these cells are consistent with some psychophysical observations of human vision at the short wave-lengths. (author)

  10. A constructive Indian country response to the evidence-based program mandate.

    Science.gov (United States)

    Walker, R Dale; Bigelow, Douglas A

    2011-01-01

    Over the last 20 years governmental mandates for preferentially funding evidence-based "model" practices and programs has become doctrine in some legislative bodies, federal agencies, and state agencies. It was assumed that what works in small sample, controlled settings would work in all community settings, substantially improving safety, effectiveness, and value-for-money. The evidence-based "model" programs mandate has imposed immutable "core components," fidelity testing, alien programming and program developers, loss of familiar programs, and resource capacity requirements upon tribes, while infringing upon their tribal sovereignty and consultation rights. Tribal response in one state (Oregon) went through three phases: shock and rejection; proposing an alternative approach using criteria of cultural appropriateness, aspiring to evaluability; and adopting logic modeling. The state heard and accepted the argument that the tribal way of knowing is different and valid. Currently, a state-authorized tribal logic model and a review panel process are used to approve tribal best practices for state funding. This constructive response to the evidence-based program mandate elevates tribal practices in the funding and regulatory world, facilitates continuing quality improvement and evaluation, while ensuring that practices and programs remain based on local community context and culture. This article provides details of a model that could well serve tribes facing evidence-based model program mandates throughout the country.

  11. Semiallogenic fusions of MSI+ tumor cells and activated B cells induce MSI-specific T cell responses

    International Nuclear Information System (INIS)

    Garbe, Yvette; Klier, Ulrike; Linnebacher, Michael

    2011-01-01

    Various strategies have been developed to transfer tumor-specific antigens into antigen presenting cells in order to induce cytotoxic T cell responses against tumor cells. One approach uses cellular vaccines based on fusions of autologous antigen presenting cells and allogeneic tumor cells. The fusion cells combine antigenicity of the tumor cell with optimal immunostimulatory capacity of the antigen presenting cells. Microsatellite instability caused by mutational inactivation of DNA mismatch repair genes results in translational frameshifts when affecting coding regions. It has been shown by us and others that these mutant proteins lead to the presentation of immunogenic frameshift peptides that are - in principle - recognized by a multiplicity of effector T cells. We chose microsatellite instability-induced frameshift antigens as ideal to test for induction of tumor specific T cell responses by semiallogenic fusions of microsatellite instable carcinoma cells with CD40-activated B cells. Two fusion clones of HCT116 with activated B cells were selected for stimulation of T cells autologous to the B cell fusion partner. Outgrowing T cells were phenotyped and tested in functional assays. The fusion clones expressed frameshift antigens as well as high amounts of MHC and costimulatory molecules. Autologous T cells stimulated with these fusions were predominantly CD4 + , activated, and reacted specifically against the fusion clones and also against the tumor cell fusion partner. Interestingly, a response toward 6 frameshift-derived peptides (of 14 tested) could be observed. Cellular fusions of MSI + carcinoma cells and activated B cells combine the antigen-presenting capacity of the B cell with the antigenic repertoire of the carcinoma cell. They present frameshift-derived peptides and can induce specific and fully functional T cells recognizing not only fusion cells but also the carcinoma cells. These hybrid cells may have great potential for cellular immunotherapy and

  12. Evidence for Differential Glycosylation of Trophoblast Cell Types*

    Science.gov (United States)

    Chen, Qiushi; Pang, Poh-Choo; Cohen, Marie E.; Longtine, Mark S.; Schust, Danny J.; Haslam, Stuart M.; Blois, Sandra M.; Dell, Anne; Clark, Gary F.

    2016-01-01

    Human placental villi are surfaced by the syncytiotrophoblast (STB), with a layer of cytotrophoblasts (CTB) positioned just beneath the STB. STB in normal term pregnancies is exposed to maternal immune cells in the placental intervillous space. Extravillous cytotrophoblasts (EVT) invade the decidua and spiral arteries, where they act in conjunction with natural killer (NK) cells to convert the spiral arteries into flaccid conduits for maternal blood that support a 3–4 fold increase in the rate of maternal blood flow into the placental intervillous space. The functional roles of these distinct trophoblast subtypes during pregnancy suggested that they could be differentially glycosylated. Glycomic analysis of these trophoblasts has revealed the expression of elevated levels of biantennary N-glycans in STB and CTB, with the majority of them bearing a bisecting GlcNAc. N-glycans terminated with polylactosamine extensions were also detected at low levels. A subset of the N-glycans linked to these trophoblasts were sialylated, primarily with terminal NeuAcα2–3Gal sequences. EVT were decorated with the same N-glycans as STB and CTB, except in different proportions. The level of bisecting type N-glycans was reduced, but the level of N-glycans decorated with polylactosamine sequences were substantially elevated compared with the other types of trophoblasts. The level of triantennary and tetraantennary N-glycans was also elevated in EVT. The sialylated N-glycans derived from EVT were completely susceptible to an α2–3 specific neuraminidase (sialidase S). The possibility exists that the N-glycans associated with these different trophoblast subpopulations could act as functional groups. These potential relationships will be considered. PMID:26929217

  13. Evidence for Differential Glycosylation of Trophoblast Cell Types.

    Science.gov (United States)

    Chen, Qiushi; Pang, Poh-Choo; Cohen, Marie E; Longtine, Mark S; Schust, Danny J; Haslam, Stuart M; Blois, Sandra M; Dell, Anne; Clark, Gary F

    2016-06-01

    Human placental villi are surfaced by the syncytiotrophoblast (STB), with a layer of cytotrophoblasts (CTB) positioned just beneath the STB. STB in normal term pregnancies is exposed to maternal immune cells in the placental intervillous space. Extravillous cytotrophoblasts (EVT) invade the decidua and spiral arteries, where they act in conjunction with natural killer (NK) cells to convert the spiral arteries into flaccid conduits for maternal blood that support a 3-4 fold increase in the rate of maternal blood flow into the placental intervillous space. The functional roles of these distinct trophoblast subtypes during pregnancy suggested that they could be differentially glycosylated. Glycomic analysis of these trophoblasts has revealed the expression of elevated levels of biantennary N-glycans in STB and CTB, with the majority of them bearing a bisecting GlcNAc. N-glycans terminated with polylactosamine extensions were also detected at low levels. A subset of the N-glycans linked to these trophoblasts were sialylated, primarily with terminal NeuAcα2-3Gal sequences. EVT were decorated with the same N-glycans as STB and CTB, except in different proportions. The level of bisecting type N-glycans was reduced, but the level of N-glycans decorated with polylactosamine sequences were substantially elevated compared with the other types of trophoblasts. The level of triantennary and tetraantennary N-glycans was also elevated in EVT. The sialylated N-glycans derived from EVT were completely susceptible to an α2-3 specific neuraminidase (sialidase S). The possibility exists that the N-glycans associated with these different trophoblast subpopulations could act as functional groups. These potential relationships will be considered. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Rapid assay for cell age response to radiation by electronic volume flow cell sorting

    International Nuclear Information System (INIS)

    Freyer, J.P.; Wilder, M.E.; Raju, M.R.

    1987-01-01

    A new technique is described for measuring cell survival as a function of cell cycle position using flow cytometric cell sorting on the basis of electronic volume signals. Sorting of cells into different cell age compartments is demonstrated for three different cell lines commonly used in radiobiological research. Using flow cytometric DNA content analysis and [ 3 H]thymidine autoradiography of the sorted cell populations, it is demonstrated that resolution of the age compartment separation is as good as or better than that reported for other cell synchronizing techniques. Variation in cell survival as a function of position in the cell cycle after a single dose of radiation as measured by volume cell sorting is similar to that determined by other cell synchrony techniques. Advantages of this method include: (1) no treatment of the cells is required, thus, this method is noncytotoxic; (2) no cell cycle progression is needed to obtain different cell age compartments; (3) the cell population can be held in complete growth medium at any desired temperature during sorting; (4) a complete radiation age - response assay can be plated in 2 h. Applications of this method are discussed, along with some technical limitations. (author)

  15. Cell responses to FGFR3 signalling: growth, differentiation and apoptosis

    International Nuclear Information System (INIS)

    L'Hote, Corine G.M.; Knowles, Margaret A.

    2005-01-01

    FGFR3 is a receptor tyrosine kinase (RTK) of the FGF receptor family, known to have a negative regulatory effect on long bone growth. Fgfr3 knockout mice display longer bones and, accordingly, most germline-activating mutations in man are associated with dwarfism. Somatically, some of the same activating mutations are associated with the human cancers multiple myeloma, cervical carcinoma and carcinoma of the bladder. How signalling through FGFR3 can lead to either chondrocyte apoptosis or cancer cell proliferation is not fully understood. Although FGFR3 can be expressed as two main splice isoforms (IIIb or IIIc), there is no apparent link with specific cell responses, which may rather be associated with the cell type or its differentiation status. Depending on cell type, differential activation of STAT proteins has been observed. STAT1 phosphorylation seems to be involved in inhibition of chondrocyte proliferation while activation of the ERK pathway inhibits chondrocyte differentiation and B-cell proliferation (as in multiple myeloma). The role of FGFR3 in epithelial cancers (bladder and cervix) is not known. Some of the cell specificity may arise via modulation of signalling by crosstalk with other signalling pathways. Recently, inhibition of the ERK pathway in achondroplastic mice has provided hope for an approach to the treatment of dwarfism. Further understanding of the ability of FGFR3 to trigger different responses depending on cell type and cellular context may lead to treatments for both skeletal dysplasias and cancer

  16. Lysophosphatidic acid mediates pleiotropic responses in skeletal muscle cells

    International Nuclear Information System (INIS)

    Jean-Baptiste, Gael; Yang Zhao; Khoury, Chamel; Greenwood, Michael T.

    2005-01-01

    Lysophosphatidic acid (LPA) is a potent modulator of growth, cell survival, and apoptosis. Although all four LPA receptors are expressed in skeletal muscle, very little is known regarding the role they play in this tissue. We used RT-PCR to demonstrate that cultured skeletal muscle C2C12 cells endogenously express multiple LPA receptor subtypes. The demonstration that LPA mediates the activation of ERK1/2 MAP kinase and Akt/PKB in C2C12 cells is consistent with the widely observed mitogenic properties of LPA. In spite of these observations, LPA did not induce proliferation in C2C12 cells. Paradoxically, we found that prolonged treatment of C2C12 cells with LPA led to caspase 3 and PARP cleavage as well as the activation of stress-associated MAP kinases JNK and p38. In spite of these typically pro-apoptotic responses, LPA did not induce cell death. Blocking ERK1/2 and Akt/PKB activation with specific pharmacological inhibitors, nevertheless, stimulated LPA-mediated apoptosis. Taken together, these results suggest that both mitogenic and apoptotic responses serve to counterbalance the effects of LPA in cultured C2C12 cells

  17. An Arabidopsis kinase cascade influences auxin-responsive cell expansion.

    Science.gov (United States)

    Enders, Tara A; Frick, Elizabeth M; Strader, Lucia C

    2017-10-01

    Mitogen-activated protein kinase (MPK) cascades are conserved mechanisms of signal transduction across eukaryotes. Despite the importance of MPK proteins in signaling events, specific roles for many Arabidopsis MPK proteins remain unknown. Multiple studies have suggested roles for MPK signaling in a variety of auxin-related processes. To identify MPK proteins with roles in auxin response, we screened mpk insertional alleles and identified mpk1-1 as a mutant that displays hypersensitivity in auxin-responsive cell expansion assays. Further, mutants defective in the upstream MAP kinase kinase MKK3 also display hypersensitivity in auxin-responsive cell expansion assays, suggesting that this MPK cascade affects auxin-influenced cell expansion. We found that MPK1 interacts with and phosphorylates ROP BINDING PROTEIN KINASE 1 (RBK1), a protein kinase that interacts with members of the Rho-like GTPases from Plants (ROP) small GTPase family. Similar to mpk1-1 and mkk3-1 mutants, rbk1 insertional mutants display auxin hypersensitivity, consistent with a possible role for RBK1 downstream of MPK1 in influencing auxin-responsive cell expansion. We found that RBK1 directly phosphorylates ROP4 and ROP6, supporting the possibility that RBK1 effects on auxin-responsive cell expansion are mediated through phosphorylation-dependent modulation of ROP activity. Our data suggest a MKK3 • MPK1 • RBK1 phosphorylation cascade that may provide a dynamic module for altering cell expansion. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  18. Directional Cell Migration in Response to Repeated Substratum Stretching

    Science.gov (United States)

    Okimura, Chika; Iwadate, Yoshiaki

    2017-10-01

    Crawling migration plays an essential role in a variety of biological phenomena, including development, wound healing, and immune system function. Migration properties such as anterior-posterior polarity, directionality, and velocity are regulated not only by the reception of a chemoattractant but also by sensing mechanical inputs from the external environment. In this review, we describe the mechanical response of migrating cells, particularly under repeated stretching of the elastic substratum, highlighting the fact that there appear to be two independent mechanosensing systems that generate the polarity needed for migration. Cells that have no stress fibers, such as Dictyostelium cells and neutrophil-like differentiated HL-60 cells, migrate perpendicular to the stretching direction via myosin II localization. Cells that do possess stress fibers, however, such as fish keratocytes, migrate parallel to the stretching via a stress-fiber-dependent process.

  19. The islet beta-cell: fuel responsive and vulnerable.

    Science.gov (United States)

    Nolan, Christopher J; Prentki, Marc

    2008-10-01

    The pancreatic beta-cell senses blood nutrient levels and is modulated by neurohormonal signals so that it secretes insulin according to the need of the organism. Nutrient sensing involves marked metabolic activation, resulting in the production of coupling signals that promote insulin biosynthesis and secretion. The beta-cell's high capacity for nutrient sensing, however, necessitates reduced protection to nutrient toxicity. This potentially explains why in susceptible individuals, chronic fuel surfeit results in beta-cell failure and type 2 diabetes. Here we discuss recent insights into first, the biochemical basis of beta-cell signaling in response to glucose, amino acids and fatty acids, and second, beta-cell nutrient detoxification. We emphasize the emerging role of glycerolipid/fatty acid cycling in these processes.

  20. Proteomic analysis of the response to cell cycle arrests in human myeloid leukemia cells.

    Science.gov (United States)

    Ly, Tony; Endo, Aki; Lamond, Angus I

    2015-01-02

    Previously, we analyzed protein abundance changes across a 'minimally perturbed' cell cycle by using centrifugal elutriation to differentially enrich distinct cell cycle phases in human NB4 cells (Ly et al., 2014). In this study, we compare data from elutriated cells with NB4 cells arrested at comparable phases using serum starvation, hydroxyurea, or RO-3306. While elutriated and arrested cells have similar patterns of DNA content and cyclin expression, a large fraction of the proteome changes detected in arrested cells are found to reflect arrest-specific responses (i.e., starvation, DNA damage, CDK1 inhibition), rather than physiological cell cycle regulation. For example, we show most cells arrested in G2 by CDK1 inhibition express abnormally high levels of replication and origin licensing factors and are likely poised for genome re-replication. The protein data are available in the Encyclopedia of Proteome Dynamics (

  1. T-cell responses to oncogenic Merkel cell polyomavirus proteins distinguish patients with Merkel cell carcinoma from healthy donors

    DEFF Research Database (Denmark)

    Lyngaa, Rikke; Pedersen, Natasja Wulff; Schrama, David

    2014-01-01

    Purpose: Merkel cell carcinoma (MCC) is a highly aggressive skin cancer with strong evidence of viral carcinogenesis. The association of MCC with the Merkel cell polyomavirus (MCPyV) may explain the explicit immunogenicity of MCC. Indeed, MCPyV-encoded proteins are likely targets for cytotoxic...

  2. Morphological responses of dissociated sponge cells to different organic substrata.

    Science.gov (United States)

    Gaino, E; Magnino, G; Burlando, B; Sara', M

    1993-06-01

    To study interactions between sponge cells and components of the extracellular matrix (ECM), cells of the calcareous sponge Clathrina cerebrum were investigated in vitro by scanning electron microscopy. Cells were settled on glass coverslips, used as controls, and on coverslips coated with various ECM components (laminin, collagens and fibronectin), and with an adhesive substance (polylysine). Cells tended to conserve a rounded shape, producing thin, stiff processes (scleropodia) and lamellipodia, whose shape and extension varied according to the substrata. Spreading was observed only on polylysine, inducing cells to assume a fibroblast-like aspect. On laminin, cell adhesion was assured only by scleropodia. On fibronectin, scleropodia and lamellipodia were present, but reduced in size and length. On collagens, laminar processes occurred among prevailing scleropodia. Measurements of cell area and perimeter allowed statistical comparison of substrata, on the basis of their induction of cell flattening and protuberance formation. In summary, sponge cells were found to modulate their morphology in response to the external environment, expressing features for dynamic activities most fully in the presence of substances close to their natural ECM constituents. These results are discussed in the context of tissue rearrangement as a basic adaptation occurring throughout the life span of these organisms.

  3. Bread making technology influences postprandial glucose response: a review of the clinical evidence.

    Science.gov (United States)

    Stamataki, Nikoleta S; Yanni, Amalia E; Karathanos, Vaios T

    2017-04-01

    Lowering postprandial glucose and insulin responses may have significant beneficial implications for prevention and treatment of metabolic disorders. Bread is a staple food consumed worldwide in a daily basis, and the use of different baking technologies may modify the glucose and insulin response. The aim of this review was to critically record the human studies examining the application of different bread making processes on postprandial glucose and insulin response to bread. Literature is rich of results which show that the use of sourdough fermentation instead of leavening with Saccharomyces cerevisiae is able to modulate glucose response to bread, whereas evidence regarding its efficacy on lowering postprandial insulin response is less clear. The presence of organic acids is possibly involved, but the exact mechanism of action is still to be confirmed. The reviewed data also revealed that the alteration of other processing conditions (method of cooking, proofing period, partial baking freezing technology) can effectively decrease postprandial glucose response to bread, by influencing physical structure and retrogradation of starch. The development of healthier bread products that benefit postprandial metabolic responses is crucial and suggested baking conditions can be used by the bread industry for the promotion of public health.

  4. Evidence for a stepwise program of extrathymic T cell development within the human tonsil

    Science.gov (United States)

    McClory, Susan; Hughes, Tiffany; Freud, Aharon G.; Briercheck, Edward L.; Martin, Chelsea; Trimboli, Anthony J.; Yu, Jianhua; Zhang, Xiaoli; Leone, Gustavo; Nuovo, Gerard; Caligiuri, Michael A.

    2012-01-01

    The development of a broad repertoire of T cells, which is essential for effective immune function, occurs in the thymus. Although some data suggest that T cell development can occur extrathymically, many researchers remain skeptical that extrathymic T cell development has an important role in generating the T cell repertoire in healthy individuals. However, it may be important in the setting of poor thymic function or congenital deficit and in the context of autoimmunity, cancer, or regenerative medicine. Here, we report evidence that a stepwise program of T cell development occurs within the human tonsil. We identified 5 tonsillar T cell developmental intermediates: (a) CD34+CD38dimLin– cells, which resemble multipotent progenitors in the bone marrow and thymus; (b) more mature CD34+CD38brightLin– cells; (c) CD34+CD1a+CD11c– cells, which resemble committed T cell lineage precursors in the thymus; (d) CD34–CD1a+CD3–CD11c– cells, which resemble CD4+CD8+ double-positive T cells in the thymus; and (e) CD34–CD1a+CD3+CD11c– cells. The phenotype of each subset closely resembled that of its thymic counterpart. The last 4 populations expressed RAG1 and PTCRA, genes required for TCR rearrangement, and all 5 subsets were capable of ex vivo T cell differentiation. TdT+ cells found within the tonsillar fibrous scaffold expressed CD34 and/or CD1a, indicating that this distinct anatomic region contributes to pre–T cell development, as does the subcapsular region of the thymus. Thus, we provide evidence of a role for the human tonsil in a comprehensive program of extrathymic T cell development. PMID:22378041

  5. Antitumour responses induced by a cell-based Reovirus vaccine in murine lung and melanoma models

    International Nuclear Information System (INIS)

    Campion, Ciorsdan A.; Soden, Declan; Forde, Patrick F.

    2016-01-01

    The ever increasing knowledge in the areas of cell biology, the immune system and the mechanisms of cancer are allowing a new phase of immunotherapy to develop. The aim of cancer vaccination is to activate the host immune system and some success has been observed particularly in the use of the BCG vaccine for bladder cancer as an immunostimulant. Reovirus, an orphan virus, has proven itself as an oncolytic virus in vitro and in vivo. Over 80 % of tumour cell lines have been found to be susceptible to Reovirus infection and it is currently in phase III clinical trials. It has been shown to induce immune responses to tumours with very low toxicities. In this study, Reovirus was examined in two main approaches in vivo, in mice, using the melanoma B16F10 and Lewis Lung Carcinoma (LLC) models. Initially, mice were treated intratumourally (IT) with Reovirus and the immune responses determined by cytokine analysis. Mice were also vaccinated using a cell-based Reovirus vaccine and subsequently exposed to a tumourigenic dose of cells (B16F10 or LLC). Using the same cell-based Reovirus vaccine, established tumours were treated and subsequent immune responses and virus retrieval investigated. Upregulation of several cytokines was observed following treatment and replication-competent virus was also retrieved from treated tumours. Varying levels of cytokine upregulation were observed and no replication-competent virus was retrieved in vaccine-treated mice. Prolongation of survival and delayed tumour growth were observed in all models and an immune response to Reovirus, either using Reovirus alone or a cell-based vaccine was also observed in all mice. This study provides evidence of immune response to tumours using a cell-based Reovirus vaccine in both tumour models investigated, B16F10 and LLC, cytokine induction was observed with prolongation of survival in almost all cases which may suggest a new method for using Reovirus in the clinic

  6. DNA mismatch repair protein MSH2 dictates cellular survival in response to low dose radiation in endometrial carcinoma cells.

    LENUS (Irish Health Repository)

    Martin, Lynn M

    2013-07-10

    DNA repair and G2-phase cell cycle checkpoint responses are involved in the manifestation of hyper-radiosensitivity (HRS). The low-dose radioresponse of MSH2 isogenic endometrial carcinoma cell lines was examined. Defects in cell cycle checkpoint activation and the DNA damage response in irradiated cells (0.2 Gy) were evaluated. HRS was expressed solely in MSH2+ cells and was associated with efficient activation of the early G2-phase cell cycle checkpoint. Maintenance of the arrest was associated with persistent MRE11, γH2AX, RAD51 foci at 2 h after irradiation. Persistent MRE11 and RAD51 foci were also evident 24 h after 0.2 Gy. MSH2 significantly enhances cell radiosensitivity to low dose IR.

  7. CD83 Antibody Inhibits Human B Cell Responses to Antigen as well as Dendritic Cell-Mediated CD4 T Cell Responses.

    Science.gov (United States)

    Wong, Kuan Y; Baron, Rebecca; Seldon, Therese A; Jones, Martina L; Rice, Alison M; Munster, David J

    2018-05-15

    Anti-CD83 Ab capable of Ab-dependent cellular cytotoxicity can deplete activated CD83 + human dendritic cells, thereby inhibiting CD4 T cell-mediated acute graft-versus-host disease. As CD83 is also expressed on the surface of activated B lymphocytes, we hypothesized that anti-CD83 would also inhibit B cell responses to stimulation. We found that anti-CD83 inhibited total IgM and IgG production in vitro by allostimulated human PBMC. Also, Ag-specific Ab responses to immunization of SCID mice xenografted with human PBMC were inhibited by anti-CD83 treatment. This inhibition occurred without depletion of all human B cells because anti-CD83 lysed activated CD83 + B cells by Ab-dependent cellular cytotoxicity and spared resting (CD83 - ) B cells. In cultured human PBMC, anti-CD83 inhibited tetanus toxoid-stimulated B cell proliferation and concomitant dendritic cell-mediated CD4 T cell proliferation and expression of IFN-γ and IL-17A, with minimal losses of B cells (80% of B cells but had no effect on CD4 T cell proliferation and cytokine expression. By virtue of the ability of anti-CD83 to selectively deplete activated, but not resting, B cells and dendritic cells, with the latter reducing CD4 T cell responses, anti-CD83 may be clinically useful in autoimmunity and transplantation. Advantages might include inhibited expansion of autoantigen- or alloantigen-specific B cells and CD4 T cells, thus preventing further production of pathogenic Abs and inflammatory cytokines while preserving protective memory and regulatory cells. Copyright © 2018 by The American Association of Immunologists, Inc.

  8. Antigen modulation of the immune response. III. Evaluation of the hypothetical short-lived memory cell

    International Nuclear Information System (INIS)

    Feldbush, T.L.; Lande, I.; Bryan, B.; O'Neill, E.

    1974-01-01

    The putative short-lived memory cells, whose existence has been suggested by the results of secondary adoptive transfer experiments, were investigated. On the basis of the following evidences we have concluded that the short-lived memory cell is probably an artifact of the adoptive transfer technique: when immune thoracic duct lymphocytes, known to consist predominantly of long-lived memory cells, were transferred to irradiated recipients and challenged at various times after transfer, approximately 80 to 90 percent of the initial response was absent by Day 14 challenge; preirradiating adoptive recipients with increasing dose of x-irradiation tended to lengthen the observed half life of memory cells; single or multiple treatments of immune donors with 0.3 mg Vinblastin before transfer resulted in neither a depression of the initial secondary response nor an alteration in the rate of decline of the memory potential; reconstitution of irradiated hosts with normal spleen cells one day before transfer of memory cells and challenge resulted in inhibition of the adoptive secondary response; and the transfer of memory cells to antigen free intermediate hosts, in which they were allowed to reside for one day or fourteen days before transfer to irradiated recipients, resulted in only a slight decline in their capacity to respond. We propose that the rapid decline of memory potential in adoptive recipients challenged at various times after transfer is due to modulating effects by the hosts as it recovers from irradiation. These effects may be the result of cell crowding or the loss of irradiation-produced stimulatory factors. The relevance of these findings to adoptive transfer systems in general and the secondary response of intact animals is discussed

  9. Touching force response of the piezoelectric Braille cell.

    Science.gov (United States)

    Smithmaitrie, Pruittikorn; Kanjantoe, Jinda; Tandayya, Pichaya

    2008-11-01

    The objective of this research is to investigate dynamic responses of the piezoelectric Braille cell when it is subjected to both electrical signal and touching force. Physical behavior of the piezoelectric actuator inside the piezoelectric Braille cell is analyzed. The mathematical model of the piezoelectric Braille system is presented. Then, data of visually impaired people using a Braille Note is studied as design information and a reference input for calculation of the piezoelectric Braille response under the touching force. The results show dynamic responses of the piezoelectric Braille cell. The designed piezoelectric bimorph has a settling time of 0.15 second. The relationship between the Braille dot height and applied voltage is linear. The behavior of the piezoelectric Braille dot when it is touched during operation shows that the dot height is decreased as the force increases. The result provides understanding of the piezoelectric Braille cell behavior under both touching force and electrical excitation simultaneously. This is the important issue for the design and development of piezoelectric Braille cells in senses of controlling Braille dot displacement or force-feedback in the future.

  10. Unraveling the response of plant cells to cytotoxic saponins

    Science.gov (United States)

    Balestrazzi, Alma; Macovei, Anca; Tava, Aldo; Avato, Pinarosa; Raimondi, Elena

    2011-01-01

    A wide range of pharmacological properties are ascribed to natural saponins, in addition to their biological activities against herbivores, plant soil-borne pathogens and pests. As for animal cells, the cytotoxicity and the chemopreventive role of saponins are mediated by a complex network of signal transduction pathways which include reactive oxygen species (ROS) and nitric oxide (NO). The involvement of other relevant components of the saponin-related signaling routes, such as the Tumor Necrosis Factor (TNF)α, the interleukin (IL)-6 and the Nuclear Transcription FactorκB (NFκB), has been highlighted in animal cells. By contrast, information concerning the response of plant cells to saponins and the related signal transduction pathways is almost missing. To date, there are only a few common features which link plant and animal cells in their response to saponins, such as the early burst in ROS and NO production and the induction of metallothioneins (MTs), small cysteine-rich, metal-binding proteins. This aspect is discussed in the present paper in view of the recent hypothesis that MTs and NO are part of a novel signal transduction pathway participating in the cell response to oxidative stress. PMID:21673512

  11. Radiation damage of hemopoietic tissue: circulating stem cells and growth factor responses

    International Nuclear Information System (INIS)

    Wagemaker, G.

    1997-01-01

    Briefly, evidence in rodents and nonhuman primates demonstrated two types of immature cells to be involved in regeneration following total body irradiation (X-rays). These cell populations can be separated and there is good responses differ. Related to these observations, experimental growth factor therapy has been ineffective at doses larger than 6-7 Gy X-rays and was shown to be optimally effective at the mid-lethal dose of 5 Gy. Consequently, at relatively high doses of radiation, treatment should initially be directed at reconstitution of growth factor responding stem cell subsets rather than at accelerated production of mature blood cells. Following cytotoxic insult to bone marrow, hemopoietic reconstitution is characterized by an increased fraction of stem cells that enters circulation. This might reflect a physiological mechanism to regulate the activities of the scattered bone marrow sites. In experimental studies with nonhuman primates, we showed that the number of circulating immature cells are proportional to those in the bone marrow and can be used for quantitative evaluation of residual stem cells numbers and to monitor the effectiveness of growth factor therapy at the immature cell level. The latter observations enables the design of growth factor treatment schedules for radiation induced myelosuppression in which thrombopenia is reduced and the recovery of immature bone marrow cells is promoted. (N.C.)

  12. The segment as the minimal planning unit in speech production: evidence based on absolute response latencies.

    Science.gov (United States)

    Kawamoto, Alan H; Liu, Qiang; Lee, Ria J; Grebe, Patricia R

    2014-01-01

    A minimal amount of information about a word must be phonologically and phonetically encoded before a person can begin to utter that word. Most researchers assume that the minimum is the complete word or possibly the initial syllable. However, there is some evidence that the initial segment is sufficient based on longer durations when the initial segment is primed. In two experiments in which the initial segment of a monosyllabic word is primed or not primed, we present additional evidence based on very short absolute response times determined on the basis of acoustic and articulatory onset relative to presentation of the complete target. We argue that the previous failures to find very short absolute response times when the initial segment is primed are due in part to the exclusive use of acoustic onset as a measure of response latency, the exclusion of responses with very short acoustic latencies, the manner of articulation of the initial segment (i.e., plosive vs. nonplosive), and individual differences. Theoretical implications of the segment as the minimal planning unit are considered.

  13. Evidence of asymmetric behavioral responses to changes in gasoline prices and taxes for different fuel types

    International Nuclear Information System (INIS)

    Bajo-Buenestado, Raúl

    2016-01-01

    Using monthly data from the Spanish gasoline retail market we explore asymmetries in consumers’ behavioral responses to changes in gasoline prices and taxes. In particular, we are interested in investigating whether an increase in gasoline taxes has a more negative impact on the demand than a –similar in magnitude– increase in the “pre-tax” price of gasoline for different fuel types. We estimate fuel consumers’ responses using a rich set of robust panel data models considering potential dynamic effects and endogeneity problems. We find evidence to confirm the existence of asymmetric responses for the demand of unleaded fuels and agricultural diesel fuel. However we cannot support this statement for the regular diesel case: for this fuel both the tax-exclusive price and the tax elasticities are roughly the same. This result agrees with the fact that “diesel drivers” tend to be better informed about changes in both fuel prices and taxes. Some implications in terms of fiscal policy and pollution and climate change policy are also discussed. - Highlights: •Provide evidence of asymmetric responses of gasoline demand due to changes in prices and taxes. •Identify differences in the elasticity of the demand of diesel fuel and unleaded gasoline. •Perform robustness checks considering dynamic effects and IV regression. •Provide some policy recommendations for future gasoline tax changes.

  14. Responses to recipient and donor B cells by genetically donor T cells from human haploidentical chimeras

    International Nuclear Information System (INIS)

    Schiff, S.; Sampson, H.; Buckley, R.

    1986-01-01

    Following administration of haploidentical stem cells to infants with severe combined immunodeficiency (SCID), mature T cells of donor karyotype appear later in the recipient without causing graft-versus-host disease. To investigate the effect of the host environment on the responsiveness of these genetically donor T cells, blood B and T lymphocytes from 6 SCID recipients, their parental donors and unrelated controls were purified by double SRBC rosetting. T cells were stimulated by irradiated B cells at a 1:1 ratio in 6 day cultures. Engrafted T cells of donor karyotype gave much smaller responses to irradiated genetically recipient B cells than did fresh donor T cells. Moreover, engrafted T cells of donor karyotype from two of the three SCIDs who are longest post-transplantation responded more vigorously (14,685 and 31,623 cpm) than fresh donor T cells (5141 and 22,709 cpm) to donor B cells. These data indicate that T lymphocytes which have matured from donor stem cells in the recipient microenvironment behave differently from those that have matured in the donor

  15. Molecular mechanisms of radioadaptive responses in human lymphoblastoid cells

    International Nuclear Information System (INIS)

    Kakimoto, Ayana; Taki, Keiko; Nakajima, Tetsuo

    2008-01-01

    Radioadaptive response is a biodefensive response observed in a variety of mammalian cells and animals where exposure to low dose radiation induces resistance against the subsequent high dose radiation. Elucidation of its mechanisms is important for risk estimation of low dose radiation because the radioadaptive response implies that low dose radiation affects cells/individuals in a different manner from high dose radiation. In the present study, we explored the molecular mechanisms of the radioadaptive response in human lymphoblastoid cells AHH-1 in terms of mutation at the hypoxanthine phosphoribosyltransferase (HPRT) gene locus. First we observed that preexposure to the priming dose in the range from 0.02 Gy to 0.2 Gy significantly reduced mutation frequency at HPRT gene locus after irradiation with 3 Gy of X rays. As no significant adaptive response was observed with the priming dose of 0.005 Gy, it was indicated that the lower limit of the priming dose to induce radioadaptive response may be between 0.005 Gy and 0.02 Gy. Second, we examined the effect of 3-amino-benzamide (3AB), an inhibitor of poly(ADP-ribose)polymerase1, which has been reported to inhibit the radioadaptive response in terms of chromosome aberration. However we could observe significant radioadaptive responses in terms of mutation even in the presence of 3AB. These findings suggested that molecular mechanisms of the radioadaptive response in terms of mutation may be different from that for radioadaptive responses in terms of chromosomal aberration, although we could not exclude a possibility that the differential effects of 3AB was due to cell type difference. Finally, by performing a comprehensive analysis of alterations in gene expression using high coverage expression profiling (HiCEP), we could identify 17 genes whose expressions were significantly altered 6 h after irradiation with 0.02 Gy. We also found 17 and 20 genes, the expressions of which were different with or without priming

  16. Are the Public Health Responsibility Deal alcohol pledges likely to improve public health? An evidence synthesis.

    Science.gov (United States)

    Knai, Cécile; Petticrew, Mark; Durand, Mary Alison; Eastmure, Elizabeth; Mays, Nicholas

    2015-08-01

    The English Public Health Responsibility Deal (RD) is a public-private partnership involving voluntary pledges between industry, government and other actors in various areas including alcohol, and designed to improve public health. This paper reviews systematically the evidence underpinning four RD alcohol pledges. We conducted a systematic review of reviews of the evidence underpinning interventions proposed in four RD alcohol pledges, namely alcohol labelling, tackling underage alcohol sales, advertising and marketing alcohol, and alcohol unit reduction. In addition, we included relevant studies of interventions where these had not been covered by a recent review. We synthesized the evidence from 14 reviews published between 2002 and 2013. Overall, alcohol labelling is likely to be of limited effect on consumption: alcohol unit content labels can help consumers assess the alcohol content of drinks; however, labels promoting drinking guidelines and pregnancy warning labels are unlikely to influence drinking behaviour. Responsible drinking messages are found to be ambiguous, and industry-funded alcohol prevention campaigns can promote drinking instead of dissuading consumption. Removing advertising near schools can contribute to reducing underage drinking; however, community mobilization and law enforcement are most effective. Finally, reducing alcohol consumption is more likely to occur if there are incentives such as making lower-strength alcohol products cheaper. The most effective evidence-based strategies to reduce alcohol-related harm are not reflected consistently in the RD alcohol pledges. The evidence is clear that an alcohol control strategy should support effective interventions to make alcohol less available and more expensive. © 2015 Society for the Study of Addiction.

  17. Epigenetics of peripheral B cell differentiation and the antibody response

    Directory of Open Access Journals (Sweden)

    Hong eZan

    2015-12-01

    Full Text Available Epigenetic modifications, such as histone post-translational modifications, DNA methylation, and alteration of gene expression by non-coding RNAs, including microRNAs (miRNAs and long non-coding RNAs (lncRNAs, are heritable changes that are independent from the genomic DNA sequence. These regulate gene activities and, therefore, cellular functions. Epigenetic modifications act in concert with transcription factors and play critical roles in B cell development and differentiation, thereby modulating antibody responses to foreign- and self-antigens. Upon antigen encounter by mature B cells in the periphery, alterations of these lymphocytes epigenetic landscape are induced by the same stimuli that drive the antibody response. Such alterations instruct B cells to undergo immunoglobulin class switch DNA recombination (CSR and somatic hypermutation (SHM, as well as differentiation to memory B cells or long-lived plasma cells for the immune memory. Inducible histone modifications, together with DNA methylation and miRNAs modulate the transcriptome, particularly the expression of activation-induced cytidine deaminase (AID, which is essential for CSR and SHM, and factors central to plasma cell differentiation, such as B lymphocyte-induced maturation protein-1 (Blimp-1. These inducible B cell-intrinsic epigenetic marks guide the maturation of antibody responses. Combinatorial histone modifications also function as histone codes to target CSR and, possibly, SHM machinery to the Ig loci by recruiting specific adaptors that can stabilize CSR/SHM factors. In addition, lncRNAs, such as recently reported lncRNA-CSR and an lncRNA generated through transcription of the S region that form G-quadruplex structures, are also important for CSR targeting. Epigenetic dysregulation in B cells, including the aberrant expression of non-coding RNAs and alterations of histone modifications and DNA methylation, can result in aberrant antibody responses to foreign antigens

  18. Cell response to quasi-monochromatic light with different coherence

    Energy Technology Data Exchange (ETDEWEB)

    Budagovsky, A V; Solovykh, N V [I.V.Michurin All-Russian Recearch Institute of Fruit Crops Genetics and Breeding (Russian Federation); Budagovskaya, O N [I.V.Michurin All-Russia Research and Development Institute of Gardening, Michurinsk, Tambov region (Russian Federation); Budagovsky, I A [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2015-04-30

    The problem of the light coherence effect on the magnitude of the photoinduced cell response is discussed. The origins of ambiguous interpretation of the known experimental results are considered. Using the biological models, essentially differing in anatomy, morphology and biological functions (acrospires of radish, blackberry microsprouts cultivated in vitro, plum pollen), the effect of statistical properties of quasi-monochromatic light (λ{sub max} = 633 nm) on the magnitude of the photoinduced cell response is shown. It is found that for relatively low spatial coherence, the cell functional activity changes insignificantly. The maximal enhancement of growing processes (stimulating effect) is observed when the coherence length L{sub coh} and the correlation radius r{sub cor} are greater than the cell size, i.e., the entire cell fits into the field coherence volume. In this case, the representative indicators (germination of seeds and pollen, the spears length) exceeds those of non-irradiated objects by 1.7 – 3.9 times. For more correct assessment of the effect of light statistical properties on photocontrol processes, it is proposed to replace the qualitative description (coherent – incoherent) with the quantitative one, using the determination of spatial and temporal correlation functions and comparing them with the characteristic dimensions of the biological structures, e.g., the cell size. (biophotonics)

  19. Plasma-Sprayed Titanium Patterns for Enhancing Early Cell Responses

    Science.gov (United States)

    Shi, Yunqi; Xie, Youtao; Pan, Houhua; Zheng, Xuebin; Huang, Liping; Ji, Fang; Li, Kai

    2016-06-01

    Titanium coating has been widely used as a biocompatible metal in biomedical applications. However, the early cell responses and long-term fixation of titanium implants are not satisfied. To obviate these defects, in this paper, micro-post arrays with various widths (150-1000 μm) and intervals (100-300 μm) were fabricated on the titanium substrate by template-assisted plasma spraying technology. In vitro cell culture experiments showed that MC3T3-E1 cells exhibited significantly higher osteogenic differentiation as well as slightly improved adhesion and proliferation on the micro-patterned coatings compared with the traditional one. The cell number on the pattern with 1000 µm width reached 130% after 6 days of incubation, and the expressions of osteopontin (OPN) as well as osteocalcin (OC) were doubled. No obvious difference was found in cell adhesion on various size patterns. The present micro-patterned coatings proposed a new modification method for the traditional plasma spraying technology to enhance the early cell responses and convenience for the bone in-growth.

  20. Heterogeneous response of isolated adult rat heart cells to insulin

    International Nuclear Information System (INIS)

    Haworth, R.A.; Hunter, D.R.; Berkoff, H.A.

    1984-01-01

    3-O-Methylglucose uptake by Ca2+-resistant adult rat heart cells in suspension was measured, free of artifactual inhibitor-insensitive uptake, and with an accuracy of +/- 1.9% pellet water. (Ca2+-resistant cells are cells which retain their original rod-shaped morphology in the presence of physiological levels of Ca2+.) High levels of insulin (10(-6) M) stimulated the rate of 3-O-methylglucose uptake approximately 10-fold. In the presence of low levels of insulin (3 X 10(-11) M, 10(-10) M) uptake was biphasic; it could not be described by a single exponential function within experimental error, but required the sum of two exponentials. Deviation from a single exponential function was not so great with high levels of insulin (10(-6) M) or no insulin. Cell sugar uptake was also investigated using autoradiography of cells which had accumulated [2-14C]deoxyglucose under similar conditions. This showed considerable heterogeneity of 2-deoxyglucose uptake by cells treated with low levels of insulin, but significantly less heterogeneity of 2-deoxyglucose uptake by cells treated with high levels of insulin. It is concluded that the deviation of 3-O-methylglucose uptake from a single exponential observed at low insulin levels can be accounted for in terms of a heterogeneous response of cells to insulin

  1. Marrow fat cell: response to x-ray induced aplasia

    International Nuclear Information System (INIS)

    Bathija, A.; Ohanian, M.; Davis, S.; Trubowitz, S.

    1979-01-01

    Adipose tissue is an integral structural component of normal rabbit marrow and is believed to behave primarily as a cushion in response to hemopoietic proliferation, accommodating to changes in hemopoiesis by change in either size or number or both of the fat cells in order to maintain constancy of the marrow volume. To test this hypothesis, aplasia of the right femur of New Zealand white rabbits was induced by x irradiation with 8000 rads; the left unirradiated limb served as control. Twenty-four hours before sacrifice 50 μCi of palmitate-114C was administered intravenously and the marrow of both femurs removed. Samples of perinephric fat were taken for comparison. Fat cell volume, C14 palmitate turnover and fatty acid composition were determined. The total number of fat cells in the entire marrow of both femurs was calculated. The measurements showed no difference in size or fatty acid turnover of the fat cells in the irradiated aplastic marrow from the cells of the control marrow. The number of fat cells in both the irradiated and the unirradiated control femurs was essentially the same. These findings do not support the view that marrow fat cells respond to diminished hematopoiesis by either increase in their volume or number. In addition, the findings suggest that both marrow and subcutaneous fat cells are fairly resistant to high doses of x-ray irradiation

  2. Evidence from Individual Inference for High-Dimensional Coexistence: Long-Term Experiments on Recruitment Response

    Science.gov (United States)

    Clark, James S.; Soltoff, Benjamin D.; Powell, Amanda S.; Read, Quentin D.

    2012-01-01

    Background For competing species to coexist, individuals must compete more with others of the same species than with those of other species. Ecologists search for tradeoffs in how species might partition the environment. The negative correlations among competing species that would be indicative of tradeoffs are rarely observed. A recent analysis showed that evidence for partitioning the environment is available when responses are disaggregated to the individual scale, in terms of the covariance structure of responses to environmental variation. That study did not relate that variation to the variables to which individuals were responding. To understand how this pattern of variation is related to niche variables, we analyzed responses to canopy gaps, long viewed as a key variable responsible for species coexistence. Methodology/Principal Findings A longitudinal intervention analysis of individual responses to experimental canopy gaps with 12 yr of pre-treatment and 8 yr post-treatment responses showed that species-level responses are positively correlated – species that grow fast on average in the understory also grow fast on average in response to gap formation. In other words, there is no tradeoff. However, the joint distribution of individual responses to understory and gap showed a negative correlation – species having individuals that respond most to gaps when previously growing slowly also have individuals that respond least to gaps when previously growing rapidly (e.g., Morus rubra), and vice versa (e.g., Quercus prinus). Conclusions/Significance Because competition occurs at the individual scale, not the species scale, aggregated species-level parameters and correlations hide the species-level differences needed for coexistence. By disaggregating models to the scale at which the interaction occurs we show that individual variation provides insight for species differences. PMID:22393349

  3. Evidence from individual inference for high-dimensional coexistence: long-term experiments on recruitment response.

    Directory of Open Access Journals (Sweden)

    James S Clark

    Full Text Available BACKGROUND: For competing species to coexist, individuals must compete more with others of the same species than with those of other species. Ecologists search for tradeoffs in how species might partition the environment. The negative correlations among competing species that would be indicative of tradeoffs are rarely observed. A recent analysis showed that evidence for partitioning the environment is available when responses are disaggregated to the individual scale, in terms of the covariance structure of responses to environmental variation. That study did not relate that variation to the variables to which individuals were responding. To understand how this pattern of variation is related to niche variables, we analyzed responses to canopy gaps, long viewed as a key variable responsible for species coexistence. METHODOLOGY/PRINCIPAL FINDINGS: A longitudinal intervention analysis of individual responses to experimental canopy gaps with 12 yr of pre-treatment and 8 yr post-treatment responses showed that species-level responses are positively correlated--species that grow fast on average in the understory also grow fast on average in response to gap formation. In other words, there is no tradeoff. However, the joint distribution of individual responses to understory and gap showed a negative correlation--species having individuals that respond most to gaps when previously growing slowly also have individuals that respond least to gaps when previously growing rapidly (e.g., Morus rubra, and vice versa (e.g., Quercus prinus. CONCLUSIONS/SIGNIFICANCE: Because competition occurs at the individual scale, not the species scale, aggregated species-level parameters and correlations hide the species-level differences needed for coexistence. By disaggregating models to the scale at which the interaction occurs we show that individual variation provides insight for species differences.

  4. Mouse Model of Devil Facial Tumour Disease establishes that an effective immune response can be generated against the cancer cells

    Directory of Open Access Journals (Sweden)

    Terry L Pinfold

    2014-05-01

    Full Text Available The largest carnivorous marsupial in Australia, the Tasmanian devil (Sarcophilus harrisii is facing extinction in the wild due to a transmissible cancer known as Devil Facial Tumour Disease (DFTD. DFTD is a clonal cell line transmitted from host to host with 100% mortality and no known immunity. While it was first considered that low genetic diversity of the population of devils enabled the allograft transmission of DFTD recent evidence reveals that genetically diverse animals succumb to the disease. The lack of an immune response against the DFTD tumor cells may be due to a lack of immunogenicity of the tumor cells. This could facilitate transmission between devils. To test immunogenicity, mice were injected with viable DFTD cells and anti-DFTD immune responses analyzed. A range of antibody isotypes against DFTD cells was detected, indicating that as DFTD cells can induce an immune response they are immunogenic. This was supported by cytokine production, when splenocytes from mice injected with DFTD cells were cultured in vitro with DFTD cells and the supernatant analyzed. There was a significant production of IFN-γ and TNF-α following the first injection with DFTD cells and a significant production of IL-6 and IL-10 following the second injection. Splenocytes from naïve or immunized mice killed DFTD cells in in vitro cytotoxicity assays. Thus they are also targets for immunological destruction. We conclude that as an immune response can be generated against DFTD cells they would be suitable targets for a vaccine.

  5. Human neuronal cell protein responses to Nipah virus infection

    Directory of Open Access Journals (Sweden)

    Hassan Sharifah

    2007-06-01

    Full Text Available Abstract Background Nipah virus (NiV, a recently discovered zoonotic virus infects and replicates in several human cell types. Its replication in human neuronal cells, however, is less efficient in comparison to other fully susceptible cells. In the present study, the SK-N-MC human neuronal cell protein response to NiV infection is examined using proteomic approaches. Results Method for separation of the NiV-infected human neuronal cell proteins using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE was established. At least 800 protein spots were resolved of which seven were unique, six were significantly up-regulated and eight were significantly down-regulated. Six of these altered proteins were identified using mass spectrometry (MS and confirmed using MS/MS. The heterogenous nuclear ribonucleoprotein (hnRNP F, guanine nucleotide binding protein (G protein, voltage-dependent anion channel 2 (VDAC2 and cytochrome bc1 were present in abundance in the NiV-infected SK-N-MC cells in contrast to hnRNPs H and H2 that were significantly down-regulated. Conclusion Several human neuronal cell proteins that are differentially expressed following NiV infection are identified. The proteins are associated with various cellular functions and their abundance reflects their significance in the cytopathologic responses to the infection and the regulation of NiV replication. The potential importance of the ratio of hnRNP F, and hnRNPs H and H2 in regulation of NiV replication, the association of the mitochondrial protein with the cytopathologic responses to the infection and induction of apoptosis are highlighted.

  6. Leptin Suppresses Mouse Taste Cell Responses to Sweet Compounds.

    Science.gov (United States)

    Yoshida, Ryusuke; Noguchi, Kenshi; Shigemura, Noriatsu; Jyotaki, Masafumi; Takahashi, Ichiro; Margolskee, Robert F; Ninomiya, Yuzo

    2015-11-01

    Leptin is known to selectively suppress neural and behavioral responses to sweet-tasting compounds. However, the molecular basis for the effect of leptin on sweet taste is not known. Here, we report that leptin suppresses sweet taste via leptin receptors (Ob-Rb) and KATP channels expressed selectively in sweet-sensitive taste cells. Ob-Rb was more often expressed in taste cells that expressed T1R3 (a sweet receptor component) than in those that expressed glutamate-aspartate transporter (a marker for Type I taste cells) or GAD67 (a marker for Type III taste cells). Systemically administered leptin suppressed taste cell responses to sweet but not to bitter or sour compounds. This effect was blocked by a leptin antagonist and was absent in leptin receptor-deficient db/db mice and mice with diet-induced obesity. Blocking the KATP channel subunit sulfonylurea receptor 1, which was frequently coexpressed with Ob-Rb in T1R3-expressing taste cells, eliminated the effect of leptin on sweet taste. In contrast, activating the KATP channel with diazoxide mimicked the sweet-suppressing effect of leptin. These results indicate that leptin acts via Ob-Rb and KATP channels that are present in T1R3-expressing taste cells to selectively suppress their responses to sweet compounds. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  7. Identification of dendritic cells, B cell and T cell subsets in Tasmanian devil lymphoid tissue; evidence for poor immune cell infiltration into devil facial tumors.

    Science.gov (United States)

    Howson, Lauren J; Morris, Katrina M; Kobayashi, Takumi; Tovar, Cesar; Kreiss, Alexandre; Papenfuss, Anthony T; Corcoran, Lynn; Belov, Katherine; Woods, Gregory M

    2014-05-01

    The Tasmanian devil is under threat of extinction due to the transmissible devil facial tumor disease (DFTD). This fatal tumor is an allograft that does not induce an immune response, raising questions about the activity of Tasmanian devil immune cells. T and B cell analysis has been limited by a lack of antibodies, hence the need to produce such reagents. Amino acid sequence analysis revealed that CD4, CD8, IgM, and IgG were closely related to other marsupials. Monoclonal antibodies were produced against CD4, CD8, IgM, and IgG by generating bacterial fusion proteins. These, and commercial antibodies against CD1a and CD83, identified T cells, B cells and dendritic cells by immunohistochemistry. CD4(+) and CD8(+) T cells were identified in pouch young thymus, adult lymph nodes, spleen, bronchus- and gut-associated lymphoid tissue. Their anatomical distribution was characteristic of mammalian lymphoid tissues with more CD4(+) than CD8(+) cells in lymph nodes and splenic white pulp. IgM(+) and IgG(+) B cells were identified in adult lymph nodes, spleen, bronchus-associated lymphoid tissue and gut-associated lymphoid tissue, with more IgM(+) than IgG(+) cells. Dendritic cells were identified in lymph node, spleen and skin. This distribution is consistent with eutherian mammals and other marsupials, indicating they have the immune cell subsets for an anti-tumor immunity. Devil facial tumor disease tumors contained more CD8(+) than CD4(+) cells, but in low numbers. There were also low numbers of CD1a(+) and MHC class II(+) cells, but no CD83(+) IgM(+) or IgG(+) B cells, consistent with poor immune cell infiltration. © 2014 The Authors. The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology Published by Wiley Periodicals, Inc.

  8. HIF-mediated innate immune responses: cell signaling and therapeutic implications

    Directory of Open Access Journals (Sweden)

    Harris AJ

    2014-05-01

    Full Text Available Alison J Harris, AA Roger Thompson, Moira KB Whyte, Sarah R Walmsley Academic Unit of Respiratory Medicine, Department of Infection and Immunity, University of Sheffield, Sheffield, UK Abstract: Leukocytes recruited to infected, damaged, or inflamed tissues during an immune response must adapt to oxygen levels much lower than those in the circulation. Hypoxia inducible factors (HIFs are key mediators of cellular responses to hypoxia and, as in other cell types, HIFs are critical for the upregulation of glycolysis, which enables innate immune cells to produce adenosine triphosphate anaerobically. An increasing body of evidence demonstrates that hypoxia also regulates many other innate immunological functions, including cell migration, apoptosis, phagocytosis of pathogens, antigen presentation and production of cytokines, chemokines, and angiogenic and antimicrobial factors. Many of these functions are mediated by HIFs, which are not only stabilized posttranslationally by hypoxia, but also transcriptionally upregulated by inflammatory signals. Here, we review the role of HIFs in the responses of innate immune cells to hypoxia, both in vitro and in vivo, with a particular focus on myeloid cells, on which the majority of studies have so far been carried out. Keywords: hypoxia, neutrophils, monocytes, macrophages

  9. Timescale of silver nanoparticle transformation in neural cell cultures impacts measured cell response

    International Nuclear Information System (INIS)

    Hume, Stephanie L.; Chiaramonti, Ann N.; Rice, Katherine P.; Schwindt, Rani K.; MacCuspie, Robert I.; Jeerage, Kavita M.

    2015-01-01

    Both serum protein concentration and ionic strength are important factors in nanoparticle transformation within cell culture environments. However, silver nanoparticles are not routinely tracked at their working concentration in the specific medium used for in vitro toxicology studies. Here we evaluated the transformation of electrostatically stabilized citrate nanoparticles (C-AgNPs) and sterically stabilized polyvinylpyrrolidone nanoparticles (PVP-AgNPs) in a low-serum (∼ 0.2 mg/mL bovine serum albumin) culture medium, while measuring the response of rat cortex neural progenitor cells, which differentiate in this culture environment. After 24 h, silver nanoparticles at concentrations up to 10 µg/mL did not affect adenosine triphosphate levels, whereas silver ions decreased adenosine triphosphate levels at concentrations of 1.1 µg/mL or higher. After 240 h, both silver nanoparticles, as well as silver ion, unambiguously decreased adenosine triphosphate levels at concentrations of 1 and 1.1 µg/mL, respectively, suggesting particle dissolution. Particle transformation was investigated in 1:10 diluted, 1:2 diluted, or undiluted differentiation medium, all having an identical protein concentration, to separate the effect of serum protein stabilization from ionic strength destabilization. Transmission electron microscopy images indicated that particles in 1:10 medium were not surrounded by proteins, whereas particles became clustered within a non-crystalline protein matrix after 24 h in 1:2 medium and at 0 h in undiluted medium. Despite evidence for a protein corona, particles were rapidly destabilized by high ionic strength media. Polyvinylpyrrolidone increased the stability of singly dispersed particles compared to citrate ligands; however, differences were negligible after 4 h in 1:2 medium or after 1 h in undiluted medium. Thus low-serum culture environments do not provide sufficient colloidal stability for long-term toxicology studies with citrate

  10. Timescale of silver nanoparticle transformation in neural cell cultures impacts measured cell response

    Energy Technology Data Exchange (ETDEWEB)

    Hume, Stephanie L.; Chiaramonti, Ann N.; Rice, Katherine P.; Schwindt, Rani K. [National Institute of Standards and Technology (NIST), Applied Chemicals and Materials Division (United States); MacCuspie, Robert I. [National Institute of Standards and Technology (NIST), Materials Measurement Science Division (United States); Jeerage, Kavita M., E-mail: jeerage@boulder.nist.gov [National Institute of Standards and Technology (NIST), Applied Chemicals and Materials Division (United States)

    2015-07-15

    Both serum protein concentration and ionic strength are important factors in nanoparticle transformation within cell culture environments. However, silver nanoparticles are not routinely tracked at their working concentration in the specific medium used for in vitro toxicology studies. Here we evaluated the transformation of electrostatically stabilized citrate nanoparticles (C-AgNPs) and sterically stabilized polyvinylpyrrolidone nanoparticles (PVP-AgNPs) in a low-serum (∼ 0.2 mg/mL bovine serum albumin) culture medium, while measuring the response of rat cortex neural progenitor cells, which differentiate in this culture environment. After 24 h, silver nanoparticles at concentrations up to 10 µg/mL did not affect adenosine triphosphate levels, whereas silver ions decreased adenosine triphosphate levels at concentrations of 1.1 µg/mL or higher. After 240 h, both silver nanoparticles, as well as silver ion, unambiguously decreased adenosine triphosphate levels at concentrations of 1 and 1.1 µg/mL, respectively, suggesting particle dissolution. Particle transformation was investigated in 1:10 diluted, 1:2 diluted, or undiluted differentiation medium, all having an identical protein concentration, to separate the effect of serum protein stabilization from ionic strength destabilization. Transmission electron microscopy images indicated that particles in 1:10 medium were not surrounded by proteins, whereas particles became clustered within a non-crystalline protein matrix after 24 h in 1:2 medium and at 0 h in undiluted medium. Despite evidence for a protein corona, particles were rapidly destabilized by high ionic strength media. Polyvinylpyrrolidone increased the stability of singly dispersed particles compared to citrate ligands; however, differences were negligible after 4 h in 1:2 medium or after 1 h in undiluted medium. Thus low-serum culture environments do not provide sufficient colloidal stability for long-term toxicology studies with citrate

  11. New evidence for the origin of intracranial germ cell tumours from primordial germ cells

    DEFF Research Database (Denmark)

    Hoei-Hansen, C E; Sehested, A; Juhler, M

    2006-01-01

    that it is not required for the initiation of malignant germ cell transformation. The expression of genes associated with embryonic stem cell pluripotency in CNS germ cell tumours strongly suggests that these tumours are derived from cells that retain, at least partially, an embryonic stem cell-like phenotype, which...... germ cell tumours and analysed expression of a wide panel of stem cell-related proteins (C-KIT, OCT-3/4 (POU5F1), AP-2gamma (TFAP2C), and NANOG) and developmentally regulated germ cell-specific proteins (including MAGE-A4, NY-ESO-1, and TSPY). Expression at the protein level was analysed in 21 children...... and young adults with intracranial germinomas and non-germinomas, contributing to a careful description of these unusual tumours and adding to the understanding of pathogenesis. Stem cell related proteins were highly expressed in intracranial germ cell tumours, and many similarities were detected...

  12. Response of maternal immune cells of irradiation of mouse embryos

    International Nuclear Information System (INIS)

    Nicholls, E.M.; Markovic, B.

    1988-01-01

    This work began as an attempt to explain the paradox of pregnancy - the survival and growth of the semi-allogenic embryo in an immunologically hostile environment. In 1982 and 1983 we reported the tracing of quinacrine labelled maternal leukocytes (WBC) in maternal, placental and embryonic mouse tissues by fluorescence microscopy. We found that cells in the placenta phagocytose labelled WBC, so that after 1-2 hours the labelled nuclear DNA is found as brightly fluorescing particles in the cytoplasm of the phagocytes with no evidence of it in the nuclei. Identical cells were observed in slide preparations of embryos which had been carefully separated from their placentas. We also found a small population of intact labelled lymphocytes, clearly maternal in origin, in the embryos. This seems to be another paradox - placental phagocytes are observed to be phagocytosing maternal WBC in the placenta and embryo, but there are also free maternal cells in the placenta and embryo. A theoretical explanation is that maternal lymphocytes alloreactive against the embryo will attempt to react with placental cells and in the process be phagocytosed, while other maternal cells will be able to enter the embryo where they could have a surveillance function, removing dead or mutant embryonic cells. To test this theory a series of experiments were carried out and are reported

  13. Mitochondrial respiration controls lysosomal function during inflammatory T cell responses

    Science.gov (United States)

    Baixauli, Francesc; Acín-Pérez, Rebeca; Villarroya-Beltrí, Carolina; Mazzeo, Carla; Nuñez-Andrade, Norman; Gabandé-Rodriguez, Enrique; Dolores Ledesma, Maria; Blázquez, Alberto; Martin, Miguel Angel; Falcón-Pérez, Juan Manuel; Redondo, Juan Miguel; Enríquez, Jose Antonio; Mittelbrunn, Maria

    2016-01-01

    Summary The endolysosomal system is critical for the maintenance of cellular homeostasis. However, how endolysosomal compartment is regulated by mitochondrial function is largely unknown. We have generated a mouse model with defective mitochondrial function in CD4+ T lymphocytes by genetic deletion of the mitochondrial transcription factor A (Tfam). Mitochondrial respiration-deficiency impairs lysosome function, promotes p62 and sphingomyelin accumulation and disrupts endolysosomal trafficking pathways and autophagy, thus linking a primary mitochondrial dysfunction to a lysosomal storage disorder. The impaired lysosome function in Tfam-deficient cells subverts T cell differentiation toward pro-inflammatory subsets and exacerbates the in vivo inflammatory response. Restoration of NAD+ levels improves lysosome function and corrects the inflammatory defects in Tfam-deficient T cells. Our results uncover a mechanism by which mitochondria regulate lysosome function to preserve T cell differentiation and effector functions, and identify novel strategies for intervention in mitochondrial-related diseases. PMID:26299452

  14. Muscarinic receptor-mediated inositol tetrakisphosphate response in bovine adrenal chromaffin cells

    International Nuclear Information System (INIS)

    Sanborn, B.B.; Schneider, A.S.

    1990-01-01

    Inositol trisphosphate (IP 3 ), a product of the phosphoinositide cycle, mobilizes intracellular Ca 2+ in many cell types. New evidence suggests that inositol tetrakisphosphate (IP 4 ), an IP 3 derivative, may act as another second messenger to further alter calcium homeostasis. However, the function and mechanism of action of IP 4 are presently unresolved. We now report evidence of muscarinic receptor-mediated accumulation of IP 4 in bovine adrenal chromaffin cells, a classic neurosecretory system in which calcium movements have been well studied. Muscarine stimulated an increase in [ 3 H]IP 4 and [ 3 H]IP 3 accumulation in chromaffin cells and this effect was completely blocked by atropine. [ 3 H]IP 4 accumulation was detectable within 15 sec, increased to a maximum by 30 sec and thereafter declined. 2,3-diphosphoglycerate, an inhibitor of IP 3 and IP 4 hydrolysis, enhanced accumulation of these inositol polyphosphates. The results provide the first evidence of a rapid inositol tetrakisphosphate response in adrenal chromaffin cells, which should facilitate the future resolution of the relationship between IP 4 and calcium homeostasis

  15. β2-adrenergic receptor-mediated negative regulation of group 2 innate lymphoid cell responses.

    Science.gov (United States)

    Moriyama, Saya; Brestoff, Jonathan R; Flamar, Anne-Laure; Moeller, Jesper B; Klose, Christoph S N; Rankin, Lucille C; Yudanin, Naomi A; Monticelli, Laurel A; Putzel, Gregory Garbès; Rodewald, Hans-Reimer; Artis, David

    2018-03-02

    The type 2 inflammatory response is induced by various environmental and infectious stimuli. Although recent studies identified group 2 innate lymphoid cells (ILC2s) as potent sources of type 2 cytokines, the molecular pathways controlling ILC2 responses are incompletely defined. Here we demonstrate that murine ILC2s express the β 2 -adrenergic receptor (β 2 AR) and colocalize with adrenergic neurons in the intestine. β 2 AR deficiency resulted in exaggerated ILC2 responses and type 2 inflammation in intestinal and lung tissues. Conversely, β 2 AR agonist treatment was associated with impaired ILC2 responses and reduced inflammation in vivo. Mechanistically, we demonstrate that the β 2 AR pathway is a cell-intrinsic negative regulator of ILC2 responses through inhibition of cell proliferation and effector function. Collectively, these data provide the first evidence of a neuronal-derived regulatory circuit that limits ILC2-dependent type 2 inflammation. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  16. Stimulation of dendritic cells enhances immune response after photodynamic therapy

    Science.gov (United States)

    Mroz, Pawel; Castano, Ana P.; Hamblin, Michael R.

    2009-02-01

    Photodynamic therapy (PDT) involves the administration of photosensitizers followed by illumination of the primary tumor with red light producing reactive oxygen species that cause vascular shutdown and tumor cell necrosis and apoptosis. Anti-tumor immunity is stimulated after PDT due to the acute inflammatory response, priming of the immune system to recognize tumor-associated antigens (TAA). The induction of specific CD8+ Tlymphocyte cells that recognize major histocompatibility complex class I (MHC-I) restricted epitopes of TAAs is a highly desirable goal in cancer therapy. The PDT killed tumor cells may be phagocytosed by dendritic cells (DC) that then migrate to draining lymph nodes and prime naÃve T-cells that recognize TAA epitopes. This process is however, often sub-optimal, in part due to tumor-induced DC dysfunction. Instead of DC that can become mature and activated and have a potent antigen-presenting and immune stimulating phenotype, immature dendritic cells (iDC) are often found in tumors and are part of an immunosuppressive milieu including regulatory T-cells and immunosuppressive cytokines such as TGF-beta and IL10. We here report on the use of a potent DC activating agent, an oligonucleotide (ODN) that contains a non-methylated CpG motif and acts as an agonist of toll like receptor (TLR) 9. TLR activation is a danger signal to notify the immune system of the presence of invading pathogens. CpG-ODN (but not scrambled non-CpG ODN) increased bone-marrow DC activation after exposure to PDT-killed tumor cells, and significantly increased tumor response to PDT and mouse survival after peri-tumoral administration. CpG may be a valuable immunoadjuvant to PDT especially for tumors that produce DC dysfunction.

  17. Dysregulation of type 2 innate lymphoid cells and TH2 cells impairs pollutant-induced allergic airway responses.

    Science.gov (United States)

    De Grove, Katrien C; Provoost, Sharen; Hendriks, Rudi W; McKenzie, Andrew N J; Seys, Leen J M; Kumar, Smitha; Maes, Tania; Brusselle, Guy G; Joos, Guy F

    2017-01-01

    Although the prominent role of T H 2 cells in type 2 immune responses is well established, the newly identified type 2 innate lymphoid cells (ILC2s) can also contribute to orchestration of allergic responses. Several experimental and epidemiologic studies have provided evidence that allergen-induced airway responses can be further enhanced on exposure to environmental pollutants, such as diesel exhaust particles (DEPs). However, the components and pathways responsible remain incompletely known. We sought to investigate the relative contribution of ILC2 and adaptive T H 2 cell responses in a murine model of DEP-enhanced allergic airway inflammation. Wild-type, Gata-3 +/nlslacZ (Gata-3-haploinsufficient), RAR-related orphan receptor α (RORα) fl/fl IL7R Cre (ILC2-deficient), and recombination-activating gene (Rag) 2 -/- mice were challenged with saline, DEPs, or house dust mite (HDM) or DEP+HDM. Airway hyperresponsiveness, as well as inflammation, and intracellular cytokine expression in ILC2s and T H 2 cells in the bronchoalveolar lavage fluid and lung tissue were assessed. Concomitant DEP+HDM exposure significantly enhanced allergic airway inflammation, as characterized by increased airway eosinophilia, goblet cell metaplasia, accumulation of ILC2s and T H 2 cells, type 2 cytokine production, and airway hyperresponsiveness compared with sole DEPs or HDM. Reduced Gata-3 expression decreased the number of functional ILC2s and T H 2 cells in DEP+HDM-exposed mice, resulting in an impaired DEP-enhanced allergic airway inflammation. Interestingly, although the DEP-enhanced allergic inflammation was marginally reduced in ILC2-deficient mice that received combined DEP+HDM, it was abolished in DEP+HDM-exposed Rag2 -/- mice. These data indicate that dysregulation of ILC2s and T H 2 cells attenuates DEP-enhanced allergic airway inflammation. In addition, a crucial role for the adaptive immune system was shown on concomitant DEP+HDM exposure. Copyright © 2016 American

  18. "The Lower Threshold" phenomenon in tumor cells toward endogenous digitalis-like compounds: Responsible for tumorigenesis?

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    Heidrun Weidemann

    2012-01-01

    Full Text Available Since their first discovery as potential anti-cancer drugs decades ago, there is increasing evidence that digitalis-like compounds (DLC have anti-tumor effects. Less is known about endogenous DLC (EDLC metabolism and regulation. As stress hormones synthesized in and secreted from the adrenal gland, they likely take part in the hypothalamo-pituitary-adrenal (HPA axis. In a previous study, we revealed reduced EDLC concentrations in plasma and organs from immune-compromised animals and proposed that a similar situation of a deregulated HPA axis with "adrenal EDLF exhaustion" may contribute to tumorigenesis in chronic stress situations. Here, we put forward the hypothesis that a lowered EDLC response threshold of tumor cells as compared with normal cells increases the risk of tumorigenesis, especially in those individuals with reduced EDLC plasma concentrations after chronic stress exposure. We will evaluate this hypothesis by (a summarizing the effects of different DLC concentrations on tumor as compared with normal cells and (b reviewing some essential differences in the Na/K-ATPase of tumor as compared with normal cells (isoform pattern, pump activity, mutations of other signalosome receptors. We will conclude that (1 tumor cells, indeed, seem to have their individual "physiologic" EDLC response range that already starts at pmolar levels and (2 that individuals with markedly reduced (pmolar EDLC plasma levels are predisposed to cancer because these EDLC concentrations will predominantly stimulate the proliferation of tumor cells. Finally, we will summarize preliminary results from our department supporting this hypothesis.

  19. Is cell survival a determinant of the in situ response of 9L tumours

    International Nuclear Information System (INIS)

    Wheeler, K.T.; Wallen, C.A.

    1980-01-01

    The influence of growth rate, location, size and potential lethal damage (PLD) recovery on the cellular radiosensitivity and the tumour response was studied in 9L/Ro and 9L/SF rat tumours. The median day of death of rats bearing the intracerebral (i.c.) 9L/Ro tumours was 16-18 days; for i.c. 9L/SF tumours it was 23-25 days. The doubling time of 9L/Ro cells was slightly faster than for 9L/SF cells both in culture and in the brain. The cellular radiosensitivity of both i.c. tumour cell sublines was identical. However, subcutaneous (s.c.) 9L/Ro tumour cells were more resistant. There was no evidence of a substantial hypoxic fraction in either site. When i.c. 9L/Ro and 9L/SF tumours of similar size were treated with fractionated doses of BCNU, X-rays or combinations of the two, the responses of the two tumours were essentially identical. The rate of recovery from radiation-induced PLD was identical in the two sublines and the two sites. Increase in life-span of rats bearing i.c. 9L/Ro tumours appeared to be correlated with the tumour cell kill measured after completion of PLD recovery rather than with the tumour cell kill determined immediately after irradiation. (author)

  20. Nasal solitary chemoreceptor cell responses to bitter and trigeminal stimulants in vitro.

    Science.gov (United States)

    Gulbransen, Brian D; Clapp, Tod R; Finger, Thomas E; Kinnamon, Sue C

    2008-06-01

    Nasal trigeminal chemosensitivity in mice and rats is mediated in part by epithelial solitary chemoreceptor (chemosensory) cells (SCCs), but the exact role of these cells in chemoreception is unclear. Histological evidence suggests that SCCs express elements of the bitter taste transduction pathway including T2R (bitter taste) receptors, the G protein alpha-gustducin, PLCbeta2, and TRPM5, leading to speculation that SCCs are the receptor cells that mediate trigeminal nerve responses to bitter taste receptor ligands. To test this hypothesis, we used calcium imaging to determine whether SCCs respond to classic bitter-tasting or trigeminal stimulants. SCCs from the anterior nasal cavity were isolated from transgenic mice in which green fluorescent protein (GFP) expression was driven by either TRPM5 or gustducin. Isolated cells were exposed to a variety of test stimuli to determine which substances caused an increase in intracellular Ca2+ ([Ca2+]i). GFP-positive cells respond with increased [Ca2+]i to the bitter receptor ligand denatonium and this response is blocked by the PLC inhibitor U73122. In addition, GFP+ cells respond to the neuromodulators adenosine 5'-triphosphate and acetylcholine but only very rarely to other bitter-tasting or trigeminal stimuli. Our results demonstrate that TRPM5- and gustducin-expressing nasal SCCs respond to the T2R agonist denatonium via a PLC-coupled transduction cascade typical of T2Rs in the taste system.

  1. Metabolic Responses in Endothelial Cells Following Exposure to Ketone Bodies

    Directory of Open Access Journals (Sweden)

    Erika Meroni

    2018-02-01

    Full Text Available The ketogenic diet (KD is a high-fat, low-carbohydrate diet based on the induction of the synthesis of ketone bodies (KB. Despite its widespread use, the systemic impact of KD is not completely understood. The purpose of this study was to evaluate the effects of physiological levels of KB on HMEC-1 endothelial cells. To this aim, DNA oxidative damage and the activation of Nrf2, a known transcriptional factor involved in cell responses to oxidative stress, were assessed. The exposure of cells to KB exerted a moderate genotoxic effect, measured by a significant increase in DNA oxidative damage. However, cells pre-treated with KB for 48 h and subjected to a secondary oxidative insult (H2O2, significantly decreased DNA damage compared to control oxidized cells. This protection occurred by the activation of Nrf2 pathway. In KB-treated cells, we found increased levels of Nrf2 in nuclear extracts and higher gene expression of HO-1, a target gene of Nrf2, compared to control cells. These results suggest that KB, by inducing moderate oxidative stress, activate the transcription factor Nrf2, which induces the transcription of target genes involved in the cellular antioxidant defense system.

  2. Primed T cell responses to chemokines are regulated by the immunoglobulin-like molecule CD31.

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    Madhav Kishore

    Full Text Available CD31, an immunoglobulin-like molecule expressed by leukocytes and endothelial cells, is thought to contribute to the physiological regulation T cell homeostasis due to the presence of two immunotyrosine-based inhibitory motifs in its cytoplasmic tail. Indeed, loss of CD31 expression leads to uncontrolled T cell-mediated inflammation in a variety of experimental models of disease and certain CD31 polymorphisms correlate with increased disease severity in human graft-versus-host disease and atherosclerosis. The molecular mechanisms underlying CD31-mediated regulation of T cell responses have not yet been clarified. We here show that CD31-mediated signals attenuate T cell chemokinesis both in vitro and in vivo. This effect selectively affects activated/memory T lymphocytes, in which CD31 is clustered on the cell membrane where it segregates to the leading edge. We provide evidence that this molecular segregation, which does not occur in naïve T lymphocytes, might lead to cis-CD31 engagement on the same membrane and subsequent interference with the chemokine-induced PI3K/Akt signalling pathway. We propose that CD31-mediated modulation of memory T cell chemokinesis is a key mechanism by which this molecule contributes to the homeostatic regulation of effector T cell immunity.

  3. Deficiency in DNA damage response of enterocytes accelerates intestinal stem cell aging in Drosophila.

    Science.gov (United States)

    Park, Joung-Sun; Jeon, Ho-Jun; Pyo, Jung-Hoon; Kim, Young-Shin; Yoo, Mi-Ae

    2018-03-07

    Stem cell dysfunction is closely linked to tissue and organismal aging and age-related diseases, and heavily influenced by the niche cells' environment. The DNA damage response (DDR) is a key pathway for tissue degeneration and organismal aging; however, the precise protective role of DDR in stem cell/niche aging is unclear. The Drosophila midgut is an excellent model to study the biology of stem cell/niche aging because of its easy genetic manipulation and its short lifespan. Here, we showed that deficiency of DDR in Drosophila enterocytes (ECs) accelerates intestinal stem cell (ISC) aging. We generated flies with knockdown of Mre11 , Rad50 , Nbs1 , ATM , ATR , Chk1 , and Chk2 , which decrease the DDR system in ECs. EC-specific DDR depletion induced EC death, accelerated the aging of ISCs, as evidenced by ISC hyperproliferation, DNA damage accumulation, and increased centrosome amplification, and affected the adult fly's survival. Our data indicated a distinct effect of DDR depletion in stem or niche cells on tissue-resident stem cell proliferation. Our findings provide evidence of the essential role of DDR in protecting EC against ISC aging, thus providing a better understanding of the molecular mechanisms of stem cell/niche aging.

  4. Protective immunization with B16 melanoma induces antibody response and not cytotoxic T cell response

    International Nuclear Information System (INIS)

    Sarzotti, M.; Sriyuktasuth, P.; Klimpel, G.R.; Cerny, J.

    1986-01-01

    C57BL/6 mice immunized with three intraperitoneal injections of syngeneic, irradiated B16 melanoma cells, became resistant to B16 tumor challenge. Immunized mice had high levels of serum antibody against a membrane antigen of B16 cells. The B16 antigen recognized by the anti-B16 sera formed a major band of 90 KD in gel electrophoresis. The anti-B16 antibody was partially protective when mixed with B16 cells and injected into normal recipient mice. Surprisingly, B16 resistance mice were incapable of generating cytotoxic T cells (CTL) specific for the B16 tumor. Both spleen and lymph node cell populations from immunized mice did not generate B16-specific CTL. Allogeneic mice (DBA/2 or C3H) were also unable to generate B16-specific CTL: however, alloreactive CTL produced in these strains of mice by immunization with C57BL/6 lymphocytes, did kill B16 target cells. Interestingly, spleen cells from syngeneic mice immunized with B16 tumor produced 6-fold more interleukin-2 (IL-2) than normal spleen cells, in vitro. These data suggest that immunization with B16 tumor activates a helper subset of T cells (for antibody and IL-2 production) but not the effector CTL response

  5. Student Perceptions of Auditor Responses to Evidence of Suspicious Activities: An Experimental Assessment

    Directory of Open Access Journals (Sweden)

    David S Murphy

    2015-12-01

    Full Text Available This study assessed student perceptions of auditor responses to evidence that a client failed to respond appropriately to suspicious activities that could indicate money laundering. Subjects were presented with a series of randomized cases in which partner type (new vs. experienced, firm type (regional vs. international and audit fee materiality (not material, material to the local office only, material to the firm were manipulated asked to indicate their perceptions of the likelihood that an audit partner would discuss such evidence with the client, and the likelihood that the issue would be disclosed by the auditor. Both partner type and audit fee materiality was found to have significant effects on perceived likelihoods.

  6. Single cells for forensic DNA analysis--from evidence material to test tube.

    Science.gov (United States)

    Brück, Simon; Evers, Heidrun; Heidorn, Frank; Müller, Ute; Kilper, Roland; Verhoff, Marcel A

    2011-01-01

    The purpose of this project was to develop a method that, while providing morphological quality control, allows single cells to be obtained from the surfaces of various evidence materials and be made available for DNA analysis in cases where only small amounts of cell material are present or where only mixed traces are found. With the SteREO Lumar.V12 stereomicroscope and UV unit from Zeiss, it was possible to detect and assess single epithelial cells on the surfaces of various objects (e.g., glass, plastic, metal). A digitally operated micromanipulator developed by aura optik was used to lift a single cell from the surface of evidence material and to transfer it to a conventional PCR tube or to an AmpliGrid(®) from Advalytix. The actual lifting of the cells was performed with microglobes that acted as carriers. The microglobes were held with microtweezers and were transferred to the DNA analysis receptacles along with the adhering cells. In a next step, the PCR can be carried out in this receptacle without removing the microglobe. Our method allows a single cell to be isolated directly from evidence material and be made available for forensic DNA analysis. © 2010 American Academy of Forensic Sciences.

  7. Evidence for selection in response to radiation exposure: Pinus sylvestris in the Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    Kuchma, Oleksandra; Finkeldey, Reiner

    2011-01-01

    Changes of genetic structures due to viability selection are likely to occur in populations exposed to rapidly and extremely changing environmental conditions after catastrophic events. However, very little is known about the extent of selective responses and in particular the proportion of the genome involved in putatively adaptive reactions for non-model plants. We used amplified fragment length polymorphisms (AFLPs) in order to investigate genetic differences between pine (Pinus sylvestris) trees which were partially exposed to extreme environmental conditions. Genetic variation patterns of pines exposed to high radiation in the Chernobyl exclusion zone with or without phenotypic stress symptoms were compared to control trees with a similar origin. Six percent of the investigated loci (15 of 222 loci) were identified as candidates for selective responses. Moderate differentiation was observed between groups of trees showing either weak or strong phenotypic responses to high radiation levels. - Highlights: → Genetic variation patterns of pines exposed to high radiation were investigated. → Pines with or without phenotypic stress symptoms were compared to control trees. → AFLP markers were used to reveal evidences of selection processes. → 15 of 222 loci are identified as candidates for selective responses. → Moderate differentiation is observed between irradiated and control trees. - Genetic responses to the exposure of trees to radiation in the Chernobyl zone may involve adaptive changes at a comparatively large part of the genome.

  8. Subcellular localization, mobility, and kinetic activity of glucokinase in glucose-responsive insulin-secreting cells.

    Science.gov (United States)

    Stubbs, M; Aiston, S; Agius, L

    2000-12-01

    We investigated the subcellular localization, mobility, and activity of glucokinase in MIN6 cells, a glucose-responsive insulin-secreting beta-cell line. Glucokinase is present in the cytoplasm and a vesicular/granule compartment that is partially colocalized with insulin granules. The granular staining of glucokinase is preserved after permeabilization of the cells with digitonin. There was no evidence for changes in distribution of glucokinase between the cytoplasm and the granule compartment during incubation of the cells with glucose. The rate of release of glucokinase and of phosphoglucoisomerase from digitonin-permeabilized cells was slower when cells were incubated at an elevated glucose concentration (S0.5 approximately 15 mmol/l). This effect of glucose was counteracted by competitive inhibitors of glucokinase (5-thioglucose and mannoheptulose) but was unaffected by fructose analogs and may be due to changes in cell shape or conformation of the cytoskeleton that are secondary to glucose metabolism. Based on the similar release of glucokinase and phosphoglucoisomerase, we found no evidence for specific binding of cytoplasmic digitonin-extractable glucokinase. The affinity of beta-cells for glucose is slightly lower than that in cell extracts and, unlike that in hepatocytes, is unaffected by fructose, tagatose, or a high-K+ medium, which is consistent with the lack of change in glucokinase distribution or release. We conclude that glucokinase is present in two locations, cytoplasm and the granular compartment, and that it does not translocate between them. This conclusion is consistent with the lack of adaptive changes in the glucose phosphorylation affinity. The glucokinase activity associated with the insulin granules may have a role in either direct or indirect coupling between glucose phosphorylation and insulin secretion.

  9. Evidence Supporting Intralesional Stem Cell Therapy to Improve Equine Flexor Tendon Healing

    Directory of Open Access Journals (Sweden)

    Sushmitha Durgam

    2017-01-01

    Full Text Available Clinical bottom lineCurrent experimental evidence suggests that intralesional stem cell administration improves the histological characteristics and matrix organisation of healing equine superficial digital flexor tendons (SDFT; however, the clinical relevance of these findings are not clear. Current case-based evidence suggests that cell-based therapies improve the quality of tendon healing and reduce the recurrence rates of SDFT injuries but the lack of any randomised, controlled prospective studies with function-based outcomes is still concerning, given the widespread advocacy for and use of ‘stem cell’ therapies for the treatment of equine tendon injuries. 

  10. An unexpected antibody response to an engineered influenza virus modifies CD8+ T cell responses.

    Science.gov (United States)

    Thomas, Paul G; Brown, Scott A; Yue, Wen; So, Jenny; Webby, Richard J; Doherty, Peter C

    2006-02-21

    The ovalbumin(323-339) peptide that binds H2I-A(b) was engineered into the globular heads of hemagglutinin (H) molecules from serologically non-cross-reactive H1N1 and H3N2 influenza A viruses, the aim being to analyze recall CD4+ T cell responses in a virus-induced respiratory disease. Prime/challenge experiments with these H1ova and H3ova viruses in H2(b) mice gave the predicted, ovalbumin-specific CD4+ T cell response but showed an unexpectedly enhanced, early expansion of viral epitope-specific CD8+ T cells in spleen and a greatly diminished inflammatory process in the virus-infected respiratory tract. At the same time, the primary antibody response to the H3N2 challenge virus was significantly reduced, an effect that has been associated with preexisting neutralizing antibody in other experimental systems. Analysis of serum from the H1ova-primed mice showed low-level binding to H3ova but not to the wild-type H3N2 virus. Experiments with CD4+ T cell-depleted and Ig-/- mice indicated that this cross-reactive Ig is indeed responsible for the modified pathogenesis after respiratory challenge. Furthermore, the effect does not seem to be virus-dose related, although it does require infection. These findings suggest intriguing possibilities for vaccination and, at the same time, emphasize that engineered modifications in viruses may have unintended immunological consequences.

  11. Cells responsible for tumor surveillance in man: effects of radiotherapy, chemotherapy, and biologic response modifiers

    International Nuclear Information System (INIS)

    Reizenstein, P.; Ogier, C.; Blomgren, H.; Petrini, B.; Wasserman, J.

    1985-01-01

    Currently, the most probable theory of tumor surveillance is neither the existence of any tumor-specific, antigen-dependent, T-cell-mediated cytotoxic effect that could eliminate spontaneous tumors in man and that could be used for some kind of vaccination against tumors, nor the complete absence of any surveillance or defense systems against tumors. What is probable is the cooperation of a number of antigen-independent, relatively weakly cytotoxic or possibly only cytostatic humoral and cellular effects, including nutritional immunity, tumor necrosis factor, certain cytokines, and the cytotoxic effects mediated by macrophages, NK cells, NK-like cells, and certain stimulated T-cells. One question remaining to be solved is why these antigen-independent effects do not attack normal cells. A number of plausible hypotheses are discussed. The hypothetical surveillance system is modulated both by traditional cancer treatment and by attempts at immunomodulation. Radiotherapy reduced the T-helper cell function for almost a decade, but not those of macrophages or NK cells. T-cell changes have no prognostic implication, supporting, perhaps, the suggestion of a major role for macrophages and NK cells. Cyclic adjuvant chemotherapy reduces the peripheral lymphocyte population and several lymphocyte functions but not NK activity. Most of the parameters were normalized some years following treatment, but NK activity remained elevated and Th/Ts cell ratio was still decreased. This might possibly be taken to support the surveillance role of NK cells. Bestatin increases the frequency of lymphocytes forming rosettes with sheep red blood cells (but not their mitogenic responses), enhances NK activity, and augments the phagocytic capacity of granulocytes and monocytes (but not their cytotoxic activity). 154 references

  12. Getting physicians to open the survey: little evidence that an envelope teaser increases response rates

    Directory of Open Access Journals (Sweden)

    Ziegenfuss Jeanette Y

    2012-03-01

    Full Text Available Abstract Background Physician surveys are an important tool to assess attitudes, beliefs and self-reported behaviors of this policy relevant group. In order for a physician to respond to a mailed survey, they must first open the envelope. While there is some evidence that package elements can impact physician response rates, the impact of an envelope teaser is unknown. Here we assess this by testing the impact of adding a brightly colored "$25 incentive" sticker to the outside of an envelope on response rates and nonresponse bias in a survey of physicians. Methods In the second mailing of a survey assessing physicians' moral beliefs and views on controversial health care topics, initial nonrespondents were randomly assigned to receive a survey in an envelope with a colored "$25 incentive" sticker (teaser group or an envelope without a sticker (control group. Response rates were compared between the teaser and control groups overall and by age, gender, region of the United States, specialty and years in practice. Nonresponse bias was assessed by comparing the demographic composition of the respondents to the nonrespondents in the experimental and control condition. Results No significant differences in response rates were observed between the experimental and control conditions overall (p = 0.38 or after stratifying by age, gender, region, or practice type. Within the teaser condition, there was some variation in response rate by years since graduation. There was no independent effect of the teaser on response when simultaneously controlling for demographic characteristics (OR = 0.875, p = 0.4112. Conclusions Neither response rates nor nonresponse bias were impacted by the use of an envelope teaser in a survey of physicians in the United States.

  13. B7-H3 is a potent inhibitor of human T cell activation: No evidence for B7-H3 and TREML2 interaction

    Science.gov (United States)

    Leitner, Judith; Klauser, Christoph; Pickl, Winfried F.; Stöckl, Johannes; Majdic, Otto; Bardet, Anaïs F.; Kreil, David P.; Dong, Chen; Yamazaki, Tomohide; Zlabinger, Gerhard; Pfistershammer, Katharina; Steinberger, Peter

    2010-01-01

    B7-H3 belongs to the B7 superfamily, a group of molecules that costimulate or down-modulate T cell responses. Although it was shown that B7-H3 can inhibit T cell responses, several studies - most of them performed in murine systems - found B7-H3 to act in a costimulatory manner. In this study we have specifically addressed a potential functional dualism of human B7-H3 by assessing the effect of this molecule under varying experimental conditions as well as on different T cell subsets. We show that B7-H3 does not costimulate human T cells. In presence of strong activating signals, B7-H3 potently and consistently down-modulated human T cell responses. This inhibitory effect was evident when analyzing proliferation and cytokine production and affected naïve as well as pre-activated T cells. We furthermore demonstrate that B7-H3 - T cell interaction is characterized by an early suppression of IL-2 and that T cell inhibition can be reverted by exogenous IL-2. Since TREML2 has been recently described as costimulatory receptor of murine B7-H3 we have extensively analysed interaction of human B7-H3 with TREML2 (TLT2). In these experiments we found no evidence for such an interaction. Furthermore our data do not point to a role for murine TREML2 as a receptor for murine B7-H3. PMID:19544488

  14. Evaluation of Radiation Response and Gold Nanoparticle Enhancement in Drug-Resistant Pancreatic Cancer Cells

    Science.gov (United States)

    Abourabia, Assya

    Pancreatic cancer is a major cause of cancer-related death worldwide after lung cancer and colorectal cancer Pancreatic treatment modalities consist of surgery, chemotherapy, and radiation therapy or combination of these therapies. These modalities are good to some extents but they do have some limitations. For example, during the chemotherapy, tumor cells can develop some escape mechanisms and become chemoresistant to protect themselves against the chemo drugs and pass on theses escape mechanisms to their offspring, despite the treatment given. Cancer Cells can become chemoresistant by many mechanisms, for example, decreased drug influx mechanisms, decreased of drug transport molecules, decreased drug activation, altered drug metabolism that diminishes the capacity of cytotoxic drugs, and enhanced repair of DNA damage. Given that some of these chemoresistance mechanisms may impact sensitivity to radiation. Therefore, there is a strong need for a new alternative treatment option to amplify the therapeutic efficacy of radiotherapy and eventually increase the overall efficacy of cancer treatment. Nano-radiation therapy is an emerging and promising modality aims to enhance the therapeutic efficacy of radiotherapy through the use of radiosensitizing nanoparticles. The primary goal of using GNP-enhanced radiation is that GNPs are potent radiosensitizer agents that sensitize the tumor cells to radiation, and these agents promote generation of the free radicals produced by Photo- and Auger- electrons emission at the molecular level which can enhance the effectiveness of radiation-induced cancer cell death. The main aim of this research is to analyze and compare the response to radiation of pancreatic cancer cells, PANC-1, and PANC-1 cells that are resistant to oxaliplatin, PANC-1/OR, and investigate the radiation dose enhancement effect attributable to GNP when irradiating the cells with low-energy (220 kVp) beam at various doses. Based on evidence from the existing

  15. Extracellular Alkalinization as a Defense Response in Potato Cells.

    Science.gov (United States)

    Moroz, Natalia; Fritch, Karen R; Marcec, Matthew J; Tripathi, Diwaker; Smertenko, Andrei; Tanaka, Kiwamu

    2017-01-01

    A quantitative and robust bioassay to assess plant defense response is important for studies of disease resistance and also for the early identification of disease during pre- or non-symptomatic phases. An increase in extracellular pH is known to be an early defense response in plants. In this study, we demonstrate extracellular alkalinization as a defense response in potatoes. Using potato suspension cell cultures, we observed an alkalinization response against various pathogen- and plant-derived elicitors in a dose- and time-dependent manner. We also assessed the defense response against a variety of potato pathogens, such as protists ( Phytophthora infestans and Spongospora subterranea ) and fungi ( Verticillium dahliae and Colletotrichum coccodes ). Our results show that extracellular pH increases within 30 min in proportion to the number of pathogen spores added. Consistently with the alkalinization effect, the higher transcription level of several defense-related genes and production of reactive oxygen species was observed. Our results demonstrate that the alkalinization response is an effective marker to study early stages of defense response in potatoes.

  16. Respiratory epithelial cell responses to cigarette smoke: the unfolded protein response.

    Science.gov (United States)

    Kelsen, Steven G

    2012-12-01

    Cigarette smoking exposes the respiratory epithelium to highly toxic, reactive oxygen nitrogen species which damage lung proteins in the endoplasmic reticulum (ER), the cell organelle in which all secreted and membrane proteins are processed. Accumulation of damaged or misfolded proteins in the ER, a condition termed ER stress, activates a complex cellular process termed the unfolded protein responses (UPR). The UPR acts to restore cellular protein homeostasis by regulating all aspects of protein metabolism including: protein translation and syntheses; protein folding; and protein degradation. However, activation of the UPR may also induce signaling pathways which induce inflammation and cell apoptosis. This review discusses the role of UPR in the respiratory epithelial cell response to cigarette smoke and the pathogenesis of lung diseases like COPD. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Enhancement of radiation response in human hepatocarcinoma cells by Metformin

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Ho; Kim, Won Woo; Kim, Joon; Jung, Won Gyun [Division of heavy ion clinical research, Korea University, Seoul (Korea, Republic of); Jeong, Jae Hoon; Jeong, Youn Kyoung; Kim, Mi Sook [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2012-11-15

    Metformin (1, 1-dimethylbiguanide hydrochloride), the most widely used drug to treat type 2 diabetic patients under benefit good tolerability profile and low cost, has sparked keen interest as potential anticancer agent. Preclinical studies showed that the primary mechanism of action of metformin is through its ability to activate AMP-activated protein kinase (AMPK). Metformin inhibits complex 1 in the mitochondrial electron transport chain, leading to an increase in the AMP-to-ATP ratio, then, phospholylated AMPK increase energy generation or suppress energy consumption and then, inhibits cell growth. However, important caveat in direct action theory of metformin is that millimorlar range, effective dose for inhibition tumor cell growth in vitro, cannot be achieved in patients. This is probably because metformin enter cells through the organic cation transporters OCT1 and OCT2, which is lowly expressed in human cells except liver and adipose cells. dependent pathway rather than through direct effects of the tumor cells. We analyzed combination effect of metformin and radiation focusing to HCC cell lines, which theoretically express high organic cation transporters, producing high centration of metformin in tumor cells. The purpose of this study is to investigate whether metformin had anti-tumor effects when combined with radiation as radiosensitizer in HCC. The results showed that metformin increased radiosensitizing efficacy in HCC cells , as well as in Huh7 xenograft mouse models. Interestingly, metformin effectively sensitizes IR-induced apoptosis in HCC through upregulation of cleaved PARP and caspase3 and increase synergically on DNA damage response with combined treatment.HCC, suggesting potential usefulness of combined therapy of metformin together with radiation for HCC cancer therapy.

  18. Enhancement of radiation response in human hepatocarcinoma cells by Metformin

    International Nuclear Information System (INIS)

    Kim, Eun Ho; Kim, Won Woo; Kim, Joon; Jung, Won Gyun; Jeong, Jae Hoon; Jeong, Youn Kyoung; Kim, Mi Sook

    2012-01-01

    Metformin (1, 1-dimethylbiguanide hydrochloride), the most widely used drug to treat type 2 diabetic patients under benefit good tolerability profile and low cost, has sparked keen interest as potential anticancer agent. Preclinical studies showed that the primary mechanism of action of metformin is through its ability to activate AMP-activated protein kinase (AMPK). Metformin inhibits complex 1 in the mitochondrial electron transport chain, leading to an increase in the AMP-to-ATP ratio, then, phospholylated AMPK increase energy generation or suppress energy consumption and then, inhibits cell growth. However, important caveat in direct action theory of metformin is that millimorlar range, effective dose for inhibition tumor cell growth in vitro, cannot be achieved in patients. This is probably because metformin enter cells through the organic cation transporters OCT1 and OCT2, which is lowly expressed in human cells except liver and adipose cells. dependent pathway rather than through direct effects of the tumor cells. We analyzed combination effect of metformin and radiation focusing to HCC cell lines, which theoretically express high organic cation transporters, producing high centration of metformin in tumor cells. The purpose of this study is to investigate whether metformin had anti-tumor effects when combined with radiation as radiosensitizer in HCC. The results showed that metformin increased radiosensitizing efficacy in HCC cells , as well as in Huh7 xenograft mouse models. Interestingly, metformin effectively sensitizes IR-induced apoptosis in HCC through upregulation of cleaved PARP and caspase3 and increase synergically on DNA damage response with combined treatment.HCC, suggesting potential usefulness of combined therapy of metformin together with radiation for HCC cancer therapy

  19. Curcumin prevents human dendritic cell response to immune stimulants

    International Nuclear Information System (INIS)

    Shirley, Shawna A.; Montpetit, Alison J.; Lockey, R.F.; Mohapatra, Shyam S.

    2008-01-01

    Curcumin, a compound found in the Indian spice turmeric, has anti-inflammatory and immunomodulatory properties, though the mechanism remains unclear. Dendritic cells (DCs) are important to generating an immune response and the effect of curcumin on human DCs has not been explored. The role curcumin in the DC response to bacterial and viral infection was investigated in vitro using LPS and Poly I:C as models of infection. CD14 + monocytes, isolated from human peripheral blood, were cultured in GM-CSF- and IL-4-supplemented medium to generate immature DCs. Cultures were incubated with curcumin, stimulated with LPS or Poly I:C and functional assays were performed. Curcumin prevents DCs from responding to immunostimulants and inducing CD4 + T cell proliferation by blocking maturation marker, cytokine and chemokine expression and reducing both migration and endocytosis. These data suggest a therapeutic role for curcumin as an immune suppressant

  20. Tumor Response to Radiotherapy Regulated by Endothelial Cell Apoptosis

    Science.gov (United States)

    Garcia-Barros, Monica; Paris, Francois; Cordon-Cardo, Carlos; Lyden, David; Rafii, Shahin; Haimovitz-Friedman, Adriana; Fuks, Zvi; Kolesnick, Richard

    2003-05-01

    About 50% of cancer patients receive radiation therapy. Here we investigated the hypothesis that tumor response to radiation is determined not only by tumor cell phenotype but also by microvascular sensitivity. MCA/129 fibrosarcomas and B16F1 melanomas grown in apoptosis-resistant acid sphingomyelinase (asmase)-deficient or Bax-deficient mice displayed markedly reduced baseline microvascular endothelial apoptosis and grew 200 to 400% faster than tumors on wild-type microvasculature. Thus, endothelial apoptosis is a homeostatic factor regulating angiogenesis-dependent tumor growth. Moreover, these tumors exhibited reduced endothelial apoptosis upon irradiation and, unlike tumors in wild-type mice, they were resistant to single-dose radiation up to 20 grays (Gy). These studies indicate that microvascular damage regulates tumor cell response to radiation at the clinically relevant dose range.

  1. Synthesis of alkyl-ether glycerophospholipids in rat glomerular mesangial cells: evidence for alkyldihydroxyacetone phosphate synthase activity

    International Nuclear Information System (INIS)

    Zanglis, A.; Lianos, E.A.

    1987-01-01

    We studied the ability of rat glomerular mesangial cells and their microsomal fractions to incorporate 1-[ 14 C]hexadecanol to glycerophospholipids via an O-alkyl ether linkage and assessed the presence and activity of the required enzyme: alkyl-dihydroxy acetone phosphate synthase. Suspensions of cultured mesangial cells incorporated 1-[ 14 C]hexadecanol to the phosphatidyl ethanolamine and phosphatidyl choline lipid pools, via a bond resistant to acid and base hydrolysis. When cell homogenates or microsomal fractions were incubated with palmitoyl-DHAP and 1-[ 14 C]hexadecanol, alkyl-DHAP and 1-O-alkyl glycerol were formed (alkyl:hexadecyl). The activity of the enzyme responsible for the O-alkyl product formation was calculated to be 2.5 +/- 0.3 and 544 +/- 50 pmoles/min/mg protein for mesangial cell homogenates and mesangial cell microsomes, respectively. These observations provide evidence that mesangial cells may elaborate either linked lipid precursors de novo for the biosynthesis of O-alkyl glycerophospholipids

  2. A critical examination of the numerology of antigen-binding cells: evidence for multiple receptor specificities on single cells.

    Science.gov (United States)

    Miller, A

    1977-01-01

    The data available from other laboratories as well as our own on the frequency of cells recognizing major histocompatibility antigens or conventional protein and hapten antigens is critically evaluated. The frequency of specific binding for a large number of antigens is sufficiently high to support the idea that at least part of the antigen-binding cell population must have multiple specificities. Our results suggest that these multiple specific cells result from single cells synthesizing and displaying as many as 50-100 species of receptor, each at a frequency of 10(4) per cell. A model involving gene expansion of constant-region genes is suggested and some auxilliary evidence consistent with such C-gene expansion is presented.

  3. Human influenza viruses and CD8(+) T cell responses.

    Science.gov (United States)

    Grant, Emma J; Quiñones-Parra, Sergio M; Clemens, E Bridie; Kedzierska, Katherine

    2016-02-01

    Influenza A viruses (IAVs) cause significant morbidity and mortality worldwide, despite new strain-specific vaccines being available annually. As IAV-specific CD8(+) T cells promote viral control in the absence of neutralizing antibodies, and can mediate cross-reactive immunity toward distinct IAVs to drive rapid recovery from both mild and severe influenza disease, there is great interest in developing a universal T cell vaccine. However, despite detailed studies in mouse models of influenza virus infection, there is still a paucity of data on human epitope-specific CD8(+) T cell responses to IAVs. This review focuses on our current understanding of human CD8(+) T cell immunity against distinct IAVs and discusses the possibility of achieving a CD8(+) T cell mediated-vaccine that protects against multiple, distinct IAV strains across diverse human populations. We also review the importance of CD8(+) T cell immunity in individuals highly susceptible to severe influenza infection, including those hospitalised with influenza, the elderly and Indigenous populations. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Purinergic responses of chondrogenic stem cells to dynamic loading

    Directory of Open Access Journals (Sweden)

    Gađanski Ivana

    2013-01-01

    Full Text Available In habitually loaded tissues, dynamic loading can trigger ATP (adenosine 5’- triphosphate release to extracellular environment, and result in calcium signaling via ATP binding to purine P2 receptors1. In the current study we have compared purinergic responses (ATP release of two types of cells: bovine chondrocytes (bCHs and human mesenchymal stem cells (hMSC that were encapsulated in agarose and subjected to dynamic loading. Both cell types were cultured under chondrogenic conditions, and their responses to loading were evaluated by ATP release assay in combination with connexin (Cx-sensitive fluorescent dye (Lucifer Yellow - LY and a Cx-hemichannel blocker (Flufenamic acid - FFA. In response to dynamic loading, chondrogenic hMSCs released significantly higher amounts of ATP (5-fold in comparison to the bCHs early in culture (day 2. Triggering of LY uptake in the bCHs and hMSCs by dynamic loading implies opening of the Cx-hemichannels. However, the number of LY-positive cells in hMSC-constructs was 2.5-fold lower compared to the loaded bCH-constructs, suggesting utilization of additional mechanisms of ATP release. Cx-reactive sites were detected in both bCHs and hMSCs-constructs. FFA application led to reduced ATP release both in bCHs and hMSCs, which confirms the involvement of connexin hemichannels, with more prominent effects in bCHs than in hMSCs, further implying the existence of additional mechanism of ATP release in chondrogenic hMSCs. Taken together, these results indicate stronger purinergic response to dynamic loading of chondrogenic hMSCs than primary chondrocytes, by activation of connexin hemichannels and additional mechanisms of ATP release. [Projekat Ministrastva nauke Republike Srbije, ON174028 i br. III41007

  5. Evidence for Transfer of Membranes from Mesenchymal Stem Cells to HL-1 Cardiac Cells.

    Science.gov (United States)

    Boomsma, Robert A; Geenen, David L

    2014-01-01

    This study examined the interaction of mouse bone marrow mesenchymal stem cells (MSC) with cardiac HL-1 cells during coculture by fluorescent dye labeling and then flow cytometry. MSC were layered onto confluent HL-1 cell cultures in a 1 : 4 ratio. MSC gained gap junction permeant calcein from HL-1 cells after 4 hours which was partially reduced by oleamide. After 20 hours, 99% MSC gained calcein, unaffected by oleamide. Double-labeling HL-1 cells with calcein and the membrane dye DiO resulted in transfer of both calcein and DiO to MSC. When HL-1 cells were labeled with calcein and MSC with DiO, MSC gained calcein while HL-1 cells gained DiO. Very little fusion was observed since more than 90% Sca-1 positive MSC gained DiO from HL-1 cells while less than 9% gained gap junction impermeant CMFDA after 20 hours with no Sca-1 transfer to HL-1 cells. Time dependent transfer of membrane DiD was observed from HL-1 cells to MSC (100%) and vice versa (50%) after 20 hours with more limited transfer of CMFDA. These results demonstrate that MSC and HL-1 cells exchange membrane components which may account for some of the beneficial effect of MSC in the heart after myocardial infarction.

  6. Innate Immune Responses of Bat and Human Cells to Filoviruses: Commonalities and Distinctions.

    Science.gov (United States)

    Kuzmin, Ivan V; Schwarz, Toni M; Ilinykh, Philipp A; Jordan, Ingo; Ksiazek, Thomas G; Sachidanandam, Ravi; Basler, Christopher F; Bukreyev, Alexander

    2017-04-15

    Marburg (MARV) and Ebola (EBOV) viruses are zoonotic pathogens that cause severe hemorrhagic fever in humans. The natural reservoir of MARV is the Egyptian rousette bat ( Rousettus aegyptiacus ); that of EBOV is unknown but believed to be another bat species. The Egyptian rousette develops subclinical productive infection with MARV but is refractory to EBOV. Interaction of filoviruses with hosts is greatly affected by the viral interferon (IFN)-inhibiting domains (IID). Our study was aimed at characterization of innate immune responses to filoviruses and the role of filovirus IID in bat and human cells. The study demonstrated that EBOV and MARV replicate to similar levels in all tested cell lines, indicating that permissiveness for EBOV at cell and organism levels do not necessarily correlate. Filoviruses, particularly MARV, induced a potent innate immune response in rousette cells, which was generally stronger than that in human cells. Both EBOV VP35 and VP24 IID were found to suppress the innate immune response in rousette cells, but only VP35 IID appeared to promote virus replication. Along with IFN-α and IFN-β, IFN-γ was demonstrated to control filovirus infection in bat cells but not in human cells, suggesting host species specificity of the antiviral effect. The antiviral effects of bat IFNs appeared not to correlate with induction of IFN-stimulated genes 54 and 56, which were detected in human cells ectopically expressing bat IFN-α and IFN-β. As bat IFN-γ induced the type I IFN pathway, its antiviral effect is likely to be partially induced via cross talk. IMPORTANCE Bats serve as reservoirs for multiple emerging viruses, including filoviruses, henipaviruses, lyssaviruses, and zoonotic coronaviruses. Although there is no evidence for symptomatic disease caused by either Marburg or Ebola viruses in bats, spillover of these viruses into human populations causes deadly outbreaks. The reason for the lack of symptomatic disease in bats infected with

  7. Biotin deficiency enhances the inflammatory response of human dendritic cells.

    Science.gov (United States)

    Agrawal, Sudhanshu; Agrawal, Anshu; Said, Hamid M

    2016-09-01

    The water-soluble biotin (vitamin B7) is indispensable for normal human health. The vitamin acts as a cofactor for five carboxylases that are critical for fatty acid, glucose, and amino acid metabolism. Biotin deficiency is associated with various diseases, and mice deficient in this vitamin display enhanced inflammation. Previous studies have shown that biotin affects the functions of adaptive immune T and NK cells, but its effect(s) on innate immune cells is not known. Because of that and because vitamins such as vitamins A and D have a profound effect on dendritic cell (DC) function, we investigated the effect of biotin levels on the functions of human monocyte-derived DCs. Culture of DCs in a biotin-deficient medium (BDM) and subsequent activation with LPS resulted in enhanced secretion of the proinflammatory cytokines TNF-α, IL-12p40, IL-23, and IL-1β compared with LPS-activated DCs cultured in biotin-sufficient (control) and biotin-oversupplemented media. Furthermore, LPS-activated DCs cultured in BDM displayed a significantly higher induction of IFN-γ and IL-17 indicating Th1/Th17 bias in T cells compared with cells maintained in biotin control or biotin-oversupplemented media. Investigations into the mechanisms suggested that impaired activation of AMP kinase in DCs cultured in BDM may be responsible for the observed increase in inflammatory responses. In summary, these results demonstrate for the first time that biotin deficiency enhances the inflammatory responses of DCs. This may therefore be one of the mechanism(s) that mediates the observed inflammation that occurs in biotin deficiency.

  8. Modeling T cell antigen discrimination based on feedback control of digital ERK responses.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available T-lymphocyte activation displays a remarkable combination of speed, sensitivity, and discrimination in response to peptide-major histocompatibility complex (pMHC ligand engagement of clonally distributed antigen receptors (T cell receptors or TCRs. Even a few foreign pMHCs on the surface of an antigen-presenting cell trigger effective signaling within seconds, whereas 1 x 10(5-1 x 10(6 self-pMHC ligands that may differ from the foreign stimulus by only a single amino acid fail to elicit this response. No existing model accounts for this nearly absolute distinction between closely related TCR ligands while also preserving the other canonical features of T-cell responses. Here we document the unexpected highly amplified and digital nature of extracellular signal-regulated kinase (ERK activation in T cells. Based on this observation and evidence that competing positive- and negative-feedback loops contribute to TCR ligand discrimination, we constructed a new mathematical model of proximal TCR-dependent signaling. The model made clear that competition between a digital positive feedback based on ERK activity and an analog negative feedback involving SH2 domain-containing tyrosine phosphatase (SHP-1 was critical for defining a sharp ligand-discrimination threshold while preserving a rapid and sensitive response. Several nontrivial predictions of this model, including the notion that this threshold is highly sensitive to small changes in SHP-1 expression levels during cellular differentiation, were confirmed by experiment. These results combining computation and experiment reveal that ligand discrimination by T cells is controlled by the dynamics of competing feedback loops that regulate a high-gain digital amplifier, which is itself modulated during differentiation by alterations in the intracellular concentrations of key enzymes. The organization of the signaling network that we model here may be a prototypic solution to the problem of achieving

  9. Hypothesis: Musculin is a hormone secreted by skeletal muscle, the body's largest endocrine organ. Evidence for actions on the endocrine pancreas to restrain the beta-cell mass and to inhibit insulin secretion and on the hypothalamus to co-ordinate the neuroendocrine and appetite responses to exercise.

    Science.gov (United States)

    Engler, Dennis

    2007-01-01

    Recent studies indicate that skeletal muscle may act as an endocrine organ by secreting interleukin-6 (IL-6) into the systemic circulation. From an analysis of the actions of IL-6 and of additional literature, we postulate that skeletal muscle also secretes an unidentified hormone, which we have named Musculin (Latin: musculus = muscle), which acts on the pancreatic beta-cell to restrain the size of the (beta-cell mass and to tonically inhibit insulin secretion and biosynthesis. It is suggested that the amount of Musculin secreted is determined by, and is positively correlated with, the prevailing insulin sensitivity of skeletal muscle, thereby accounting for the hyperinsulinemia that occurs in insulin resistant disorders such as type 2 diabetes mellitus, obesity, and the polycystic ovary syndrome. In addition, it is postulated that Musculin acts on the hypothalamus (arcuate nucleus, dorsomedial hypothalamic nucleus) to co-ordinate the neuroendocrine and appetite responses to exercise. However, the possibilities that Musculin may act on additional central nervous system sites and that an additional hormone(s) may be responsible for these actions are not excluded. It is suggested that a search be made for Musculin, since analogues of such a substance may be of therapeutic benefit in the treatment of the current global diabetes and obesity epidemic.

  10. Cell response to long term mechanical interaction with nanopipettes

    Science.gov (United States)

    Orynbayeva, Zulfiya; Singhal, Riju; Vitol, Elina; Bouchard, Michael; Azizkhan-Clifford, Jane; Layton, Bradley; Friedman, Gary; Gogotsi, Yury

    2009-03-01

    Traditional microinjection into cells is performed over a relatively short term. Pipettes are typically withdrawn following any kind of injection. On the other hand, there is growing interest in using nanopipettes for cellular and subcellular probing. This interest is partly due to new developments in nanopipette technology which employ carbon nanotubes and provide robustness, flexibility, and biocompatibility. However, as far as we know, no systematic study of physiological, biochemical, and biophysical processes associated with cell response to lengthy mechanical stimulations by nanopipette probing have been performed so far. We present a detailed investigation of a wide range of effects of long term pipette insertion into a cell. Both traditional glass micropipettes and the novel carbon nanotube-tipped probes were involved in this study. The mechanism of Ca2+ response to the mechanical stimuli introduced by the nanopipette, and the role of different organelles in this mechanism were studied. We hypothesize that the calcium response is a function of cytoskeleton integrity and the mode of coupling between the cytoskeleton and the plasma membrane domains.

  11. Bioanalytical evidence that chemicals in tattoo ink can induce adaptive stress responses.

    Science.gov (United States)

    Neale, Peta A; Stalter, Daniel; Tang, Janet Y M; Escher, Beate I

    2015-10-15

    Tattooing is becoming increasingly popular, particularly amongst young people. However, tattoo inks contain a complex mixture of chemical impurities that may pose a long-term risk for human health. As a first step towards the risk assessment of these complex mixtures we propose to assess the toxicological hazard potential of tattoo ink chemicals with cell-based bioassays. Targeted modes of toxic action and cellular endpoints included cytotoxicity, genotoxicity and adaptive stress response pathways. The studied tattoo inks, which were extracted with hexane as a proxy for the bioavailable fraction, caused effects in all bioassays, with the red and yellow tattoo inks having the greatest response, particularly inducing genotoxicity and oxidative stress response endpoints. Chemical analysis revealed the presence of polycyclic aromatic hydrocarbons in the tested black tattoo ink at concentrations twice the recommended level. The detected polycyclic aromatic hydrocarbons only explained 0.06% of the oxidative stress response of the black tattoo ink, thus the majority of the effect was caused by unidentified components. The study indicates that currently available tattoo inks contain components that induce adaptive stress response pathways, but to evaluate the risk to human health further work is required to understand the toxicokinetics of tattoo ink chemicals in the body. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. The Unfolded Protein Response and Cell Fate Control.

    Science.gov (United States)

    Hetz, Claudio; Papa, Feroz R

    2018-01-18

    The secretory capacity of a cell is constantly challenged by physiological demands and pathological perturbations. To adjust and match the protein-folding capacity of the endoplasmic reticulum (ER) to changing secretory needs, cells employ a dynamic intracellular signaling pathway known as the unfolded protein response (UPR). Homeostatic activation of the UPR enforces adaptive programs that modulate and augment key aspects of the entire secretory pathway, whereas maladaptive UPR outputs trigger apoptosis. Here, we discuss recent advances into how the UPR integrates information about the intensity and duration of ER stress stimuli in order to control cell fate. These findings are timely and significant because they inform an evolving mechanistic understanding of a wide variety of human diseases, including diabetes mellitus, neurodegeneration, and cancer, thus opening up the potential for new therapeutic modalities to treat these diverse diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. The CD8 T Cell Response to Respiratory Virus Infections.

    Science.gov (United States)

    Schmidt, Megan E; Varga, Steven M

    2018-01-01

    Humans are highly susceptible to infection with respiratory viruses including respiratory syncytial virus (RSV), influenza virus, human metapneumovirus, rhinovirus, coronavirus, and parainfluenza virus. While some viruses simply cause symptoms of the common cold, many respiratory viruses induce severe bronchiolitis, pneumonia, and even death following infection. Despite the immense clinical burden, the majority of the most common pulmonary viruses lack long-lasting efficacious vaccines. Nearly all current vaccination strategies are designed to elicit broadly neutralizing antibodies, which prevent severe disease following a subsequent infection. However, the mucosal antibody response to many respiratory viruses is not long-lasting and declines with age. CD8 T cells are critical for mediating clearance following many acute viral infections in the lung. In addition, memory CD8 T cells are capable of providing protection against secondary infections. Therefore, the combined induction of virus-specific CD8 T cells and antibodies may provide optimal protective immunity. Herein, we review the current literature on CD8 T cell responses induced by respiratory virus infections. Additionally, we explore how this knowledge could be utilized in the development of future vaccines against respiratory viruses, with a special emphasis on RSV vaccination.

  14. Single cell analysis of Vibrio harveyi uncovers functional heterogeneity in response to quorum sensing signals

    Directory of Open Access Journals (Sweden)

    Anetzberger Claudia

    2012-09-01

    Full Text Available Abstract Background Vibrio harveyi and closely related species are important pathogens in aquaculture. A complex quorum sensing cascade involving three autoinducers controls bioluminescence and several genes encoding virulence factors. Single cell analysis of a V. harveyi population has already indicated intercellular heterogeneity in the production of bioluminescence. This study was undertaken to analyze the expression of various autoinducer-dependent genes in individual cells. Results Here we used reporter strains bearing promoter::gfp fusions to monitor the induction/repression of three autoinducer-regulated genes in wild type conjugates at the single cell level. Two genes involved in pathogenesis - vhp and vscP, which code for an exoprotease and a component of the type III secretion system, respectively, and luxC (the first gene in the lux operon were chosen for analysis. The lux operon and the exoprotease gene are induced, while vscP is repressed at high cell density. As controls luxS and recA, whose expression is not dependent on autoinducers, were examined. The responses of the promoter::gfp fusions in individual cells from the same culture ranged from no to high induction. Importantly, simultaneous analysis of two autoinducer induced phenotypes, bioluminescence (light detection and exoproteolytic activity (fluorescence of a promoter::gfp fusion, in single cells provided evidence for functional heterogeneity within a V. harveyi population. Conclusions Autoinducers are not only an indicator for cell density, but play a pivotal role in the coordination of physiological activities within the population.

  15. Studies on the mechanism of the self restriction of T cell responses in radiation chimeras

    International Nuclear Information System (INIS)

    Fink, P.J.; Bevan, M.J.

    1981-01-01

    Recent experiments with murine radiation chimeras have shown that F 1 T cells that mature in an H-2 homozygous thymus, as is the case in [F 1 → Parent 1] chimeras, are restricted to recognizing foreign antigen in the context of Parent 1 H-2 antigens. Conflicting results on the stringency of self H-2 restriction of T cells from normal mice have suggested that the thymic restriction in chimeras may be due to active suppression of parent 2-restricted T cell clones. We have therefore conducted 3 sets of experiments to test for suppression of maturing T cells that could mediate thymic tutoring of H-2-restriction specificity in chimeras. In 2 sets of experiments, we found no evidence that suppressor cells could be exported from 1 thymus and act either intrathymically on thymocytes in a 2nd thymus or extrathymically on recent thymic emigrants. We believe current data support a role for the thymus in positive as well as negative selection of maturing thymocytes on the basis of self recognition, in the absence of any suppression. Our results do not support the concept that suppression is responsible for the difference in the degree of self preference in the T cells of chimeric mice relative to cell populations obtained from neonatally tolerant mice or from normal mice after acute negative selection

  16. Single cell analysis of Vibrio harveyi uncovers functional heterogeneity in response to quorum sensing signals.

    Science.gov (United States)

    Anetzberger, Claudia; Schell, Ursula; Jung, Kirsten

    2012-09-18

    Vibrio harveyi and closely related species are important pathogens in aquaculture. A complex quorum sensing cascade involving three autoinducers controls bioluminescence and several genes encoding virulence factors. Single cell analysis of a V. harveyi population has already indicated intercellular heterogeneity in the production of bioluminescence. This study was undertaken to analyze the expression of various autoinducer-dependent genes in individual cells. Here we used reporter strains bearing promoter::gfp fusions to monitor the induction/repression of three autoinducer-regulated genes in wild type conjugates at the single cell level. Two genes involved in pathogenesis - vhp and vscP, which code for an exoprotease and a component of the type III secretion system, respectively, and luxC (the first gene in the lux operon) were chosen for analysis. The lux operon and the exoprotease gene are induced, while vscP is repressed at high cell density. As controls luxS and recA, whose expression is not dependent on autoinducers, were examined. The responses of the promoter::gfp fusions in individual cells from the same culture ranged from no to high induction. Importantly, simultaneous analysis of two autoinducer induced phenotypes, bioluminescence (light detection) and exoproteolytic activity (fluorescence of a promoter::gfp fusion), in single cells provided evidence for functional heterogeneity within a V. harveyi population. Autoinducers are not only an indicator for cell density, but play a pivotal role in the coordination of physiological activities within the population.

  17. Alteration of Lymphocyte Phenotype and Function in Sickle Cell Anemia: Implications for Vaccine Responses

    Science.gov (United States)

    Balandya, Emmanuel; Reynolds, Teri; Obaro, Stephen; Makani, Julie

    2016-01-01

    Individuals with sickle cell anemia (SCA) have increased susceptibility to infections, secondary to impairment of immune function. Besides the described dysfunction in innate immunity, including impaired opsonization and phagocytosis of bacteria, evidence of dysfunction of T and B lymphocytes in SCA has also been reported. This includes reduction in the proportion of circulating CD4+ and CD8+ T cells, reduction of CD4+ helper : CD8+ suppressor T cell ratio, aberrant activation and dysfunction of regulatory T cells (Treg), skewing of CD4+ T cells towards Th2 response and loss of IgM-secreting CD27+IgMhighIgDlow memory B cells. These changes occur on the background of immune activation characterized by predominance of memory CD4+ T cell phenotypes, increased Th17 signaling and elevated levels of C-reactive protein and pro-inflammatory cytokines IL-6 and TNF-α, which may affect the immunogenicity and protective efficacy of vaccines available to prevent infections in SCA. Thus, in order to optimize the use of vaccines in SCA, a thorough understanding of T and B lymphocyte functions and vaccine reactivity among individuals with SCA is needed. Studies should be encouraged of different SCA populations, including sub-Saharan Africa where the burden of SCA is highest. This article summarizes our current understanding of lymphocyte biology in SCA, and highlights areas that warrant future research. PMID:27237467

  18. Evidence that pulsed electric field treatment enhances the cell wall porosity of yeast cells.

    Science.gov (United States)

    Ganeva, Valentina; Galutzov, Bojidar; Teissie, Justin

    2014-02-01

    The application of rectangular electric pulses, with 0.1-2 ms duration and field intensity of 2.5-4.5 kV/cm, to yeast suspension mediates liberation of cytoplasmic proteins without cell lysis. The aim of this study was to evaluate the effect of pulsed electric field with similar parameters on cell wall porosity of different yeast species. We found that electrically treated cells become more susceptible to lyticase digestion. In dependence on the strain and the electrical conditions, cell lysis was obtained at 2-8 times lower enzyme concentration in comparison with control untreated cells. The increase of the maximal lysis rate was between two and nine times. Furthermore, when applied at low concentration (1 U/ml), the lyticase enhanced the rate of protein liberation from electropermeabilized cells without provoking cell lysis. Significant differences in the cell surface of control and electrically treated cells were revealed by scanning electron microscopy. Data presented in this study allow us to conclude that electric field pulses provoke not only plasma membrane permeabilization, but also changes in the cell wall structure, leading to increased wall porosity.

  19. Prophylactic platelets in dengue: survey responses highlight lack of an evidence base.

    Directory of Open Access Journals (Sweden)

    James Whitehorn

    Full Text Available Dengue is the most important arboviral infection of humans. Thrombocytopenia is frequently observed in the course of infection and haemorrhage may occur in severe disease. The degree of thrombocytopenia correlates with the severity of infection, and may contribute to the risk of haemorrhage. As a result of this prophylactic platelet transfusions are sometimes advocated for the prevention of haemorrhage. There is currently no evidence to support this practice, and platelet transfusions are costly and sometimes harmful. We conducted a global survey to assess the different approaches to the use of platelets in dengue. Respondents were all physicians involved with the treatment of patients with dengue. Respondents were asked that their answers reflected what they would do if they were the treating physician. We received responses from 306 physicians from 20 different countries. The heterogeneity of the responses highlights the variation in clinical practice and lack of an evidence base in this area and underscores the importance of prospective clinical trials to address this key question in the clinical management of patients with dengue.

  20. PKC activation induces inflammatory response and cell death in human bronchial epithelial cells.

    Directory of Open Access Journals (Sweden)

    Hyunhee Kim

    Full Text Available A variety of airborne pathogens can induce inflammatory responses in airway epithelial cells, which is a crucial component of host defence. However, excessive inflammatory responses and chronic inflammation also contribute to different diseases of the respiratory system. We hypothesized that the activation of protein kinase C (PKC is one of the essential mechanisms of inflammatory response in airway epithelial cells. In the present study, we stimulated human bronchial lung epithelial (BEAS-2B cells with the phorbol ester Phorbol 12, 13-dibutyrate (PDBu, and examined gene expression profile using microarrays. Microarray analysis suggests that PKC activation induced dramatic changes in gene expression related to multiple cellular functions. The top two interaction networks generated from these changes were centered on NFκB and TNF-α, which are two commonly known pathways for cell death and inflammation. Subsequent tests confirmed the decrease in cell viability and an increase in the production of various cytokines. Interestingly, each of the increased cytokines was differentially regulated at mRNA and/or protein levels by different sub-classes of PKC isozymes. We conclude that pathological cell death and cytokine production in airway epithelial cells in various situations may be mediated through PKC related signaling pathways. These findings suggest that PKCs can be new targets for treatment of lung diseases.

  1. Natural Killer Cell Response to Chemotherapy-Stressed Cancer Cells: Role in Tumor Immunosurveillance

    Directory of Open Access Journals (Sweden)

    Alessandra Zingoni

    2017-09-01

    Full Text Available Natural killer (NK cells are innate cytotoxic lymphoid cells that actively prevent neoplastic development, growth, and metastatic dissemination in a process called cancer immunosurveillance. An equilibrium between immune control and tumor growth is maintained as long as cancer cells evade immunosurveillance. Therapies designed to kill cancer cells and to simultaneously sustain host antitumor immunity are an appealing strategy to control tumor growth. Several chemotherapeutic agents, depending on which drugs and doses are used, give rise to DNA damage and cancer cell death by means of apoptosis, immunogenic cell death, or other forms of non-apoptotic death (i.e., mitotic catastrophe, senescence, and autophagy. However, it is becoming increasingly clear that they can trigger additional stress responses. Indeed, relevant immunostimulating effects of different therapeutic programs include also the activation of pathways able to promote their recognition by immune effector cells. Among stress-inducible immunostimulating proteins, changes in the expression levels of NK cell-activating and inhibitory ligands, as well as of death receptors on tumor cells, play a critical role in their detection and elimination by innate immune effectors, including NK cells. Here, we will review recent advances in chemotherapy-mediated cellular stress pathways able to stimulate NK cell effector functions. In particular, we will address how these cytotoxic lymphocytes sense and respond to different types of drug-induced stresses contributing to anticancer activity.

  2. From microgravity to osmotic conditions: mechanical integration of plant cells in response to stress

    Science.gov (United States)

    Wojtaszek, Przemyslaw; Kasprowicz, Anna; Michalak, Michal; Janczara, Renata; Volkmann, Dieter; Baluska, Frantisek

    Chemical reactions and interactions between molecules are commonly thought of as being at the basis of Life. Research of recent years, however, is more and more evidently indicating that physical forces are profoundly affecting the functioning of life at all levels of its organiza-tion. To detect and to respond to such forces, plant cells need to be integrated mechanically. Cell walls are the outermost functional zone of plant cells. They surround the individual cells, and also form a part of the apoplast. In cell suspensions, cell walls are embedded in the cul-ture medium which can be considered as a superapoplast. Through physical and chemical interactions they provide a basis for the structural and functional cell wall-plasma membrane-cytoskeleton (WMC) continuum spanning the whole cell. Here, the working of WMC contin-uum, and the participation of signalling molecules, like NO, would be presented in the context of plant responses to stress. In addition, the effects of the changing composition of WMC continuum will be considered, with particular attention paid to the modifications of the WMC components. Plant cells are normally adapted to changing osmotic conditions, resulting from variable wa-ter availability. The appearance of the osmotic stress activates adaptory mechanisms. If the strength of osmotic stress grows relatively slowly over longer period of time, the cells are able to adapt to conditions that are lethal to non-adapted cells. During stepwise adaptation of tobacco BY-2 suspension cells to the presence of various osmotically active agents, cells diverged into independent, osmoticum type-specific lines. In response to ionic agents (NaCl, KCl), the adhe-sive properties were increased and randomly dividing cells formed clumps, while cells adapted to nonionic osmotica (mannitol, sorbitol, PEG) revealed ordered pattern of precisely positioned cell divisions, resulting in the formation of long cell files. Changes in the growth patterns were accompanied by

  3. Gene expression in epithelial cells in response to pneumovirus infection

    Directory of Open Access Journals (Sweden)

    Rosenberg Helene F

    2001-05-01

    Full Text Available Abstract Respiratory syncytial virus (RSV and pneumonia virus of mice (PVM are viruses of the family Paramyxoviridae, subfamily pneumovirus, which cause clinically important respiratory infections in humans and rodents, respectively. The respiratory epithelial target cells respond to viral infection with specific alterations in gene expression, including production of chemoattractant cytokines, adhesion molecules, elements that are related to the apoptosis response, and others that remain incompletely understood. Here we review our current understanding of these mucosal responses and discuss several genomic approaches, including differential display reverse transcription-polymerase chain reaction (PCR and gene array strategies, that will permit us to unravel the nature of these responses in a more complete and systematic manner.

  4. Cell mediated immune response in human antirabies revaccination

    Directory of Open Access Journals (Sweden)

    Débora Regina Veiga

    1987-04-01

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

  5. Distinct gut-derived lactic acid bacteria elicit divergent dendritic cell-mediated NK cell responses

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Zeuthen, Louise Hjerrild; Christensen, Hanne

    2007-01-01

    Lactic acid bacteria (LAB) are abundant in the gastrointestinal tract where they continuously regulate the immune system. NK cells are potently activated by dendritic cells (DCs) matured by inflammatory stimuli, and NK cells are present in the gut epithelium and in mesenteric lymph nodes......, but it is not known how NK-DC interactions are affected by the predominantly non-pathogenic LAB. We demonstrate that human DCs exposed to different strains of gut-derived LAB consistently induce proliferation, cytotoxicity and activation markers in autologous NK cells. On the contrary, strains of LAB differ greatly...... in their ability to induce DC-dependent IFN-gamma production by NK cells. This suggests that DCs stimulated by gut LAB may expand the pool of NK cells and increase their cytotoxic potential. Specific LAB, inducing high levels of IL-12 in DCs, may promote amplification of a type-1 response via potent stimulation...

  6. The Role of B Cells for in Vivo T Cell Responses to a Friend Virus-Induced Leukemia

    Science.gov (United States)

    Schultz, Kirk R.; Klarnet, Jay P.; Gieni, Randall S.; Hayglass, Kent T.; Greenberg, Philip D.

    1990-08-01

    B cells can function as antigen-presenting cells and accessory cells for T cell responses. This study evaluated the role of B cells in the induction of protective T cell immunity to a Friend murine leukemia virus (F-MuLV)-induced leukemia (FBL). B cell-deficient mice exhibited significantly reduced tumor-specific CD4^+ helper and CD8^+ cytotoxic T cell responses after priming with FBL or a recombinant vaccinia virus containing F-MuLV antigens. Moreover, these mice had diminished T cell responses to the vaccinia viral antigens. Tumor-primed T cells transferred into B cell-deficient mice effectively eradicated disseminated FBL. Thus, B cells appear necessary for efficient priming but not expression of tumor and viral T cell immunity.

  7. Categorical methods for the interpretation of RNA profiles as cell type evidence and their limitations

    NARCIS (Netherlands)

    de Zoete, J.; Curran, J.; Sjerps, M.

    2015-01-01

    Existing methods for the interpretation of RNA profiles as evidence for the presence of certain cell types aim for making categorical statements. Such statements limit the possibility to report the associated uncertainty. From a statistical point of view, a probabilistic approach is a preferable

  8. Intestinal Epithelial Cells Modulate Antigen-Presenting Cell Responses to Bacterial DNA

    Science.gov (United States)

    Campeau, J. L.; Salim, S. Y.; Albert, E. J.; Hotte, N.

    2012-01-01

    Intestinal epithelial cells and antigen-presenting cells orchestrate mucosal innate immunity. This study investigated the role of bacterial DNA in modulating epithelial and bone marrow-derived antigen-presenting cells (BM-APCs) and subsequent T-lymphocyte responses. Murine MODE-K epithelial cells and BM-APCs were treated with DNA from either Bifidobacterium breve or Salmonella enterica serovar Dublin directly and under coculture conditions with CD4+ T cells. Apical stimulation of MODE-K cells with S. Dublin DNA enhanced secretion of cytokines from underlying BM-APCs and induced interleukin-17 (IL-17) and gamma interferon (IFN-γ) secretion from CD4+ T cells. Bacterial DNA isolated from either strain induced maturation and increased cytokine secretion from BM-APCs. Conditioned medium from S. Dublin-treated MODE-K cells elicited an increase in cytokine secretion similar to that seen for S. Dublin DNA. Treatment of conditioned medium from MODE-K cells with RNase and protease prevented the S. Dublin-induced increased cytokine secretion. Oral feeding of mice with B. breve DNA resulted in enhanced levels of colonic IL-10 and transforming growth factor β (TGFβ) compared with what was seen for mice treated with S. Dublin DNA. In contrast, feeding mice with S. Dublin DNA increased levels of colonic IL-17 and IL-12p70. T cells from S. Dublin DNA-treated mice secreted high levels of IL-12 and IFN-γ compared to controls and B. breve DNA-treated mice. These results demonstrate that intestinal epithelial cells are able to modulate subsequent antigen-presenting and T-cell responses to bacterial DNA with pathogenic but not commensal bacterial DNA inducing effector CD4+ T lymphocytes. PMID:22615241

  9. Impaired Epstein-Barr Virus-Specific Neutralizing Antibody Response during Acute Infectious Mononucleosis Is Coincident with Global B-Cell Dysfunction.

    Science.gov (United States)

    Panikkar, Archana; Smith, Corey; Hislop, Andrew; Tellam, Nick; Dasari, Vijayendra; Hogquist, Kristin A; Wykes, Michelle; Moss, Denis J; Rickinson, Alan; Balfour, Henry H; Khanna, Rajiv

    2015-09-01

    Here we present evidence for previously unappreciated B-cell immune dysregulation during acute Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM). Longitudinal analyses revealed that patients with acute IM have undetectable EBV-specific neutralizing antibodies and gp350-specific B-cell responses, which were associated with a significant reduction in memory B cells and no evidence of circulating antibody-secreting cells. These observations correlate with dysregulation of tumor necrosis factor family members BAFF and APRIL and increased expression of FAS on circulating B cells. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  10. [SOS response of DNA repair and genetic cell instability under hypoxic conditions].

    Science.gov (United States)

    Vasil'eva, S V; Strel'tsova, D A

    2011-01-01

    The SOS DNA repair pathway is induced in E. coli as a multifunctional cell response to a wide variety of signals: UV, X or gamma-irradiation, mitomycin C or nalidixic acid treatment, thymine starvation, etc. Triggering of the system can be used as a general and early sign of DNA damage. Additionally, the SOS-response is known to be an "error-prone" DNA repair pathway and one of the sources of genetic instability. Hypoxic conditions are established to be the major factor of genetic instability as well. In this paper we for the first time studied the SOS DNA repair response under hypoxic conditions induced by the well known aerobic SOS-inducers. The SOS DNA repair response was examined as a reaction of E. coli PQ37 [sfiA::lacZ] cells to UVC, NO-donating agents and 4NQO. Here we provide evidence that those agents were able to induce the SOS DNA repair response in E. coli at anaerobic growth conditions. The process does not depend on the transcriptional activity of the universal protein of E. col anaerobic growth Fnr [4Fe-4S]2+ or can not be referred to as an indicator of genetic instability in hypoxic conditions.

  11. Evidence that Meningeal Mast Cells Can Worsen Stroke Pathology in Mice

    Science.gov (United States)

    Arac, Ahmet; Grimbaldeston, Michele A.; Nepomuceno, Andrew R.B.; Olayiwola, Oluwatobi; Pereira, Marta P.; Nishiyama, Yasuhiro; Tsykin, Anna; Goodall, Gregory J.; Schlecht, Ulrich; Vogel, Hannes; Tsai, Mindy; Galli, Stephen J.; Bliss, Tonya M.; Steinberg, Gary K.

    2015-01-01

    Stroke is the leading cause of adult disability and the fourth most common cause of death in the United States. Inflammation is thought to play an important role in stroke pathology, but the factors that promote inflammation in this setting remain to be fully defined. An understudied but important factor is the role of meningeal-located immune cells in modulating brain pathology. Although different immune cells traffic through meningeal vessels en route to the brain, mature mast cells do not circulate but are resident in the meninges. With the use of genetic and cell transfer approaches in mice, we identified evidence that meningeal mast cells can importantly contribute to the key features of stroke pathology, including infiltration of granulocytes and activated macrophages, brain swelling, and infarct size. We also obtained evidence that two mast cell-derived products, interleukin-6 and, to a lesser extent, chemokine (C-C motif) ligand 7, can contribute to stroke pathology. These findings indicate a novel role for mast cells in the meninges, the membranes that envelop the brain, as potential gatekeepers for modulating brain inflammation and pathology after stroke. PMID:25134760

  12. Differences in lifespan and rate of turnover between phytohaemagglutinin responsive cells of the bone marrow and of peripheral lymphoid organs

    International Nuclear Information System (INIS)

    Press, O.W.; Rosse, C.

    1978-01-01

    Radioautographic analyses were performed on PHA stimulated cultures of in vivo labelled cells obtained from mice previously injected with 3 H-TdR to label selectively either cells with a rapid renewal rate (RR) or a slow renewal rate (SR). PHA responsive cells in the bone marrow (BM) were found to be virtually all RR cells, whereas both RR and SR cells from lymph nodes (LN) and spleen (Spl) were stimulated by this mitogen. However, RR cells were proportionately more responsive to PHA than SR cells in all tissues examined. Only one out of 200 BM PHA blasts belonged to the SR subclass, whereas the RR/SR ratio was approximately 1/1 for LN and 2/1 for Spl. Control experiments demonstrated that significant in vitro re-utilization of 3 H-TdR from dying cells did not occur in the cultures. These results support a growing body of evidence that BM PHA responsive cells are precursor T-cells which are known to have a rapid turnover rate. (author)

  13. Response of birds to climatic variability; evidence from the western fringe of Europe

    Science.gov (United States)

    Donnelly, Alison; Cooney, Tom; Jennings, Eleanor; Buscardo, Erika; Jones, Mike

    2009-05-01

    Ireland’s geographic location on the western fringe of the European continent, together with its island status and impoverished avifauna, provides a unique opportunity to observe changes in bird migration and distribution patterns in response to changing climatic conditions. Spring temperatures have increased in western Europe over the past 30 years in line with reported global warming. These have been shown, at least in part, to be responsible for changes in the timing of life cycle events (phenology) of plants and animals. In order to investigate the response of bird species in Ireland to changes in temperature, we examined ornithological records of trans-Saharan migrants over the 31-year period 1969-1999. Analysis of the data revealed that two discrete climatic phenomena produced different responses in summer migrant bird species. Firstly, a number of long-distance migrants showed a significant trend towards earlier arrival. This trend was evident in some species and was found to be a response to increasing spring air temperature particularly in the month of March. Secondly, (1) a step change in the pattern of occurrences of non-breeding migrant bird species, and (2) an increase in the ringing data of migrant species were found to correlate with a step change in temperature in 1987-1988. These results indicate that, for migrant bird species, the impact of a sudden change in temperature can be as important as any long-term monotonic trend, and we suggest that the impact of step change events merits further investigation on a wider range of species and across a greater geographical range.

  14. Inhibition of estrogen-responsive gene activation by the retinoid X receptor beta: evidence for multiple inhibitory pathways.

    OpenAIRE

    Segars, J H; Marks, M S; Hirschfeld, S; Driggers, P H; Martinez, E; Grippo, J F; Brown, M; Wahli, W; Ozato, K

    1993-01-01

    The retinoid X receptor beta (RXR beta; H-2RIIBP) forms heterodimers with various nuclear hormone receptors and binds multiple hormone response elements, including the estrogen response element (ERE). In this report, we show that endogenous RXR beta contributes to ERE binding activity in nuclear extracts of the human breast cancer cell line MCF-7. To define a possible regulatory role of RXR beta regarding estrogen-responsive transcription in breast cancer cells, RXR beta and a reporter gene d...

  15. Gene expression based evidence of innate immune response activation in the epithelium with oral lichen planus

    Science.gov (United States)

    Adami, Guy R.; Yeung, Alexander C.F.; Stucki, Grant; Kolokythas, Antonia; Sroussi, Herve Y.; Cabay, Robert J.; Kuzin, Igor; Schwartz, Joel L.

    2014-01-01

    Objective Oral lichen planus (OLP) is a disease of the oral mucosa of unknown cause producing lesions with an intense band-like inflammatory infiltrate of T cells to the subepithelium and keratinocyte cell death. We performed gene expression analysis of the oral epithelium of lesions in subjects with OLP and its sister disease, oral lichenoid reaction (OLR), in order to better understand the role of the keratinocytes in these diseases. Design Fourteen patients with OLP or OLR were included in the study, along with a control group of 23 subjects with a variety of oral diseases and a normal group of 17 subjects with no clinically visible mucosal abnormalities. Various proteins have been associated with OLP, based on detection of secreted proteins or changes in RNA levels in tissue samples consisting of epithelium, stroma, and immune cells. The mRNA level of twelve of these genes expressed in the epithelium was tested in the three groups. Results Four genes showed increased expression in the epithelium of OLP patients: CD14, CXCL1, IL8, and TLR1, and at least two of these proteins, TLR1 and CXCL1, were expressed at substantial levels in oral keratinocytes. Conclusions Because of the large accumulation of T cells in lesions of OLP it has long been thought to be an adaptive immunity malfunction. We provide evidence that there is increased expression of innate immune genes in the epithelium with this illness, suggesting a role for this process in the disease and a possible target for treatment. PMID:24581860

  16. Effort analysis of gender differences in cardiovascular response: Further evidence involving a traditionally feminine incentive.

    Science.gov (United States)

    Barreto, Patricia; Wright, Rex A; Krubinski, Kimberlee; Molzof, Hylton; Hur, Jinwoo

    2015-07-01

    Participants were presented a moderately- or impossibly difficult cumulative mental addition task with instructions that they could win a traditionally feminine- or masculine incentive if they achieved a 90% success rate. When the incentive was feminine, systolic blood pressure responses during the task period were stronger under moderately difficult conditions among women, but low irrespective of difficulty among men - creating a gender difference only when difficulty was moderate. By contrast, when the incentive was masculine, systolic-, mean arterial- and, to a lesser degree, diastolic blood pressure responses during the task period were stronger under moderately difficult conditions irrespective of gender. The former finding confirmed expectations and adds substantively to the body of evidence favoring a recent effort analysis of gender influence on CV response to performance challenge. The latter findings conflict with what was first expected, but can be understood in terms of post hoc reasoning extended in light of participants' ratings of the masculine incentive. Copyright © 2015. Published by Elsevier B.V.

  17. Low dose decitabine treatment induces CD80 expression in cancer cells and stimulates tumor specific cytotoxic T lymphocyte responses.

    Directory of Open Access Journals (Sweden)

    Li-Xin Wang

    Full Text Available Lack of immunogenicity of cancer cells has been considered a major reason for their failure in induction of a tumor specific T cell response. In this paper, we present evidence that decitabine (DAC, a DNA methylation inhibitor that is currently used for the treatment of myelodysplastic syndrome (MDS, acute myeloid leukemia (AML and other malignant neoplasms, is capable of eliciting an anti-tumor cytotoxic T lymphocyte (CTL response in mouse EL4 tumor model. C57BL/6 mice with established EL4 tumors were treated with DAC (1.0 mg/kg body weight once daily for 5 days. We found that DAC treatment resulted in infiltration of IFN-γ producing T lymphocytes into tumors and caused tumor rejection. Depletion of CD8(+, but not CD4(+ T cells resumed tumor growth. DAC-induced CTL response appeared to be elicited by the induction of CD80 expression on tumor cells. Epigenetic evidence suggests that DAC induces CD80 expression in EL4 cells via demethylation of CpG dinucleotide sites in the promoter of CD80 gene. In addition, we also showed that a transient, low-dose DAC treatment can induce CD80 gene expression in a variety of human cancer cells. This study provides the first evidence that epigenetic modulation can induce the expression of a major T cell co-stimulatory molecule on cancer cells, which can overcome immune tolerance, and induce an efficient anti-tumor CTL response. The results have important implications in designing DAC-based cancer immunotherapy.

  18. Low Dose Decitabine Treatment Induces CD80 Expression in Cancer Cells and Stimulates Tumor Specific Cytotoxic T Lymphocyte Responses

    Science.gov (United States)

    Zhou, Ji-Hao; Yao, Yu-Shi; Li, Yong-Hui; Xu, Yi-Han; Li, Jing-Xin; Gao, Xiao-Ning; Zhou, Min-Hang; Jiang, Meng-Meng; Gao, Li; Ding, Yi; Lu, Xue-Chun; Shi, Jin-Long; Luo, Xu-Feng; Wang, Jia; Wang, Li-Li; Qu, Chunfeng; Bai, Xue-Feng; Yu, Li

    2013-01-01

    Lack of immunogenicity of cancer cells has been considered a major reason for their failure in induction of a tumor specific T cell response. In this paper, we present evidence that decitabine (DAC), a DNA methylation inhibitor that is currently used for the treatment of myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and other malignant neoplasms, is capable of eliciting an anti-tumor cytotoxic T lymphocyte (CTL) response in mouse EL4 tumor model. C57BL/6 mice with established EL4 tumors were treated with DAC (1.0 mg/kg body weight) once daily for 5 days. We found that DAC treatment resulted in infiltration of IFN-γ producing T lymphocytes into tumors and caused tumor rejection. Depletion of CD8+, but not CD4+ T cells resumed tumor growth. DAC-induced CTL response appeared to be elicited by the induction of CD80 expression on tumor cells. Epigenetic evidence suggests that DAC induces CD80 expression in EL4 cells via demethylation of CpG dinucleotide sites in the promoter of CD80 gene. In addition, we also showed that a transient, low-dose DAC treatment can induce CD80 gene expression in a variety of human cancer cells. This study provides the first evidence that epigenetic modulation can induce the expression of a major T cell co-stimulatory molecule on cancer cells, which can overcome immune tolerance, and induce an efficient anti-tumor CTL response. The results have important implications in designing DAC-based cancer immunotherapy. PMID:23671644

  19. Low dose decitabine treatment induces CD80 expression in cancer cells and stimulates tumor specific cytotoxic T lymphocyte responses.

    Science.gov (United States)

    Wang, Li-Xin; Mei, Zhen-Yang; Zhou, Ji-Hao; Yao, Yu-Shi; Li, Yong-Hui; Xu, Yi-Han; Li, Jing-Xin; Gao, Xiao-Ning; Zhou, Min-Hang; Jiang, Meng-Meng; Gao, Li; Ding, Yi; Lu, Xue-Chun; Shi, Jin-Long; Luo, Xu-Feng; Wang, Jia; Wang, Li-Li; Qu, Chunfeng; Bai, Xue-Feng; Yu, Li

    2013-01-01

    Lack of immunogenicity of cancer cells has been considered a major reason for their failure in induction of a tumor specific T cell response. In this paper, we present evidence that decitabine (DAC), a DNA methylation inhibitor that is currently used for the treatment of myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and other malignant neoplasms, is capable of eliciting an anti-tumor cytotoxic T lymphocyte (CTL) response in mouse EL4 tumor model. C57BL/6 mice with established EL4 tumors were treated with DAC (1.0 mg/kg body weight) once daily for 5 days. We found that DAC treatment resulted in infiltration of IFN-γ producing T lymphocytes into tumors and caused tumor rejection. Depletion of CD8(+), but not CD4(+) T cells resumed tumor growth. DAC-induced CTL response appeared to be elicited by the induction of CD80 expression on tumor cells. Epigenetic evidence suggests that DAC induces CD80 expression in EL4 cells via demethylation of CpG dinucleotide sites in the promoter of CD80 gene. In addition, we also showed that a transient, low-dose DAC treatment can induce CD80 gene expression in a variety of human cancer cells. This study provides the first evidence that epigenetic modulation can induce the expression of a major T cell co-stimulatory molecule on cancer cells, which can overcome immune tolerance, and induce an efficient anti-tumor CTL response. The results have important implications in designing DAC-based cancer immunotherapy.

  20. microRNA Response to Listeria monocytogenes Infection in Epithelial Cells

    Science.gov (United States)

    Izar, Benjamin; Mannala, Gopala Krishna; Mraheil, Mobarak Abu; Chakraborty, Trinad; Hain, Torsten

    2012-01-01

    microRNAs represent a family of very small non-coding RNAs that control several physiologic and pathologic processes, including host immune response and cancer by antagonizing a number of target mRNAs. There is limited knowledge about cell expression and the regulatory role of microRNAs following bacterial infections. We investigated whether infection with a Gram-positive bacterium leads to altered expression of microRNAs involved in the host cell response in epithelial cells. Caco-2 cells were infected with Listeria monocytogenes EGD-e, a mutant strain (ΔinlAB or Δhly) or incubated with purified listeriolysin (LLO). Total RNA was isolated and microRNA and target gene expression was compared to the expression in non-infected cells using microRNA microarrays and qRT-PCR. We identified and validated five microRNAs (miR- 146b, miR-16, let-7a1, miR-145 and miR-155) that were significantly deregulated following listerial infection. We show that expression patterns of particular microRNAs strongly depend on pathogen localization and the presence of bacterial effector proteins. Strikingly, miR-155 which was shown to have an important role in inflammatory responses during infection was induced by wild-type bacteria, by LLO-deficient bacteria and following incubation with purified LLO. It was downregulated following ΔinlAB infection indicating a new potent role for internalins in listerial pathogenicity and miRNA regulation. Concurrently, we observed differences in target transcript expression of the investigated miRNAs. We provide first evidence that L. monocytogenes infection leads to deregulation of a set of microRNAs with important roles in host response. Distinct microRNA expression depends on both LLO and pathogen localization. PMID:22312311

  1. The prevalence of adverse cardiometabolic responses to exercise training with evidence-based practice is low

    Directory of Open Access Journals (Sweden)

    Dalleck LC

    2015-01-01

    Full Text Available Lance C Dalleck,1 Gary P Van Guilder,2 Tara B Richardson,1 Chantal A Vella3 1Recreation, Exercise, and Sport Science Department, Western State Colorado University, Gunnison, CO, USA; 2Department of Health and Nutritional Sciences, South Dakota State University, Brookings, SD, USA; 3Department of Movement Sciences, WWAMI Medical Education Program, University of Idaho, Moscow, ID, USA Background: The purpose of this study was to determine the prevalence of individuals who experienced exercise-induced adverse cardiometabolic response (ACR, following an evidence-based, individualized, community exercise program. Methods: Prevalence of ACR was retrospectively analyzed in 332 adults (190 women, 142 men before and after a 14-week supervised community exercise program. ACR included an exercise training-induced increase in systolic blood pressure of 10 mmHg, increase in plasma triglycerides (TG of >37.0 mg/dL (0.42 mmol/L, or decrease in high-density lipoprotein cholesterol (HDL-C of >4.0 mg/dL (0.12 mmol/L. A second category of ACR was also defined – this was ACR that resulted in a metabolic syndrome component (ACR-risk as a consequence of the adverse response. Results: According to the above criteria, prevalence of ACR between baseline and post-program was systolic blood pressure (6.0%, TG (3.6%, and HDL-C (5.1%. The prevalence of ACR-risk was elevated TG (3.2%, impaired fasting blood glucose (2.7%, low HDL-C (2.2%, elevated waist circumference (1.3%, and elevated blood pressure (0.6%. Conclusion: Evidence-based practice exercise programming may attenuate the prevalence of exercise training-induced ACR. Our findings provide important preliminary evidence needed for the vision of exercise prescription as a personalized form of preventative medicine to become a reality. Keywords: evidence-based research, cardiovascular health, community-based research, metabolic health

  2. Major Histocompatibilty Complex-Restricted Adaptive Immune Responses to CT26 Colon Cancer Cell Line in Mixed Allogeneic Chimera.

    Science.gov (United States)

    Lee, K W; Choi, B; Kim, Y M; Cho, C W; Park, H; Moon, J I; Choi, G-S; Park, J B; Kim, S J

    2017-06-01

    Although the induction of mixed allogeneic chimera shows promising clinical tolerance results in organ transplantation, its clinical relevance as an anti-cancer therapy is yet unknown. We introduced a mixed allogenic chimera setting with the use of a murine colon cancer cell line, CT26, by performing double bone marrow transplantation. We analyzed donor- and recipient-restricted anti-cancer T-cell responses, and phenotypes of subpopulations of T cells. The protocol involves challenging 1 × 10 5 cells of CT26 cells intra-hepatically on day 50 after bone marrow transplantation, and, by use of CT26 lysates and an H-2L d -restricted AH1 pentamer, flow cytometric analysis was performed to detect the generation of cancer-specific CD4 + and CD8 + T cells at various time points. We found that immunocompetence against tumors depends heavily on cancer-specific CD8 + T-cell responses in a major histocompatibility complex-restricted manner; the evidence was further supported by the increase of interferon-γ-secreting CD4 + T cells. Moreover, we demonstrated that during the effector immune response to CT26 cancer challenge, there was a presence of central memory cells (CD62L hi CCR7 + ) as well as effector memory cells (CD62L lo CCR7 - ). Moreover, mixed allogeneic chimeras (BALB/c to C56BL/6 or vice versa) showed similar or heightened immune responses to CT26 cells compared with that of wild-type mice. Our results suggest that the responses of primary immunocompetency and of pre-existing memory T cells against allogeneic cancer are sustained and preserved long-term in a mixed allogeneic chimeric environment. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. The effect of cyclosporin A on the primary immune response to allogeneic red cells in rabbits.

    Science.gov (United States)

    Smith, G N

    1982-01-01

    Cyclosporin A (CSA) has been used in an attempt to suppress the primary immune response of HgA(A)-negative rabbits to A-positive red cells. The immune response was assessed by measuring the survival of a small intravenous (i.v.) dose of 51Cr-labelled A-positive cells and by testing the serum of the immunized rabbits for anti-A. In one experiment, eight A-negative rabbits were given a first i.v. injection of A-positive red cells, and CSA (25 mg/kg/day) in olive oil was given by mouth for 17-34 days. There was no evidence of impaired alloimmunization compared with the responses in control animals treated with olive oil alone. In a second experiment, eight A-negative rabbits were given a first injection of A-positive muscularly (i.m.), and CSA (25 mg/kg/day) in miglyol was given by im.m. injection for 10 days. Six of these rabbits were rendered unresponsive, and the remaining two, who showed impaired survival of the monitoring red cells, produced only low anit-A titres. Seven out of eight controls given i.m. miglyol without CSA responded with good anti-A production. Rabbits that were unresponsive to A-positive red cells responded normally to sheep red blood cells 15 weeks after CSA treatment. Higher serum levels of CSA were found following i.m. administration of the drug but treatment by this route as associated with severe toxicity in some rabbits. PMID:7056563

  4. TGF-β1 accelerates the DNA damage response in epithelial cells via Smad signaling

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeeyong; Kim, Mi-Ra; Kim, Hyun-Ji; An, You Sun; Yi, Jae Youn, E-mail: yjy_71@kcch.re.kr

    2016-08-05

    The evidence suggests that transforming growth factor-beta (TGF-β) regulates the DNA-damage response (DDR) upon irradiation, and we previously reported that TGF-β1 induced DNA ligase IV (Lig4) expression and enhanced the nonhomologous end-joining repair pathway in irradiated cells. In the present study, we investigated the effects of TGF-β1 on the irradiation-induced DDRs of A431 and HaCaT cells. Cells were pretreated with or without TGF-β1 and irradiated. At 30 min post-irradiation, DDRs were detected by immunoblotting of phospho-ATM, phospho-Chk2, and the presence of histone foci (γH2AX). The levels of all three factors were similar right after irradiation regardless of TGF-β1 pretreatment. However, they soon thereafter exhibited downregulation in TGF-β1-pretreated cells, indicating the acceleration of the DDR. Treatment with a TGF-β type I receptor inhibitor (SB431542) or transfections with siRNAs against Smad2/3 or DNA ligase IV (Lig4) reversed this acceleration of the DDR. Furthermore, the frequency of irradiation-induced apoptosis was decreased by TGF-β1 pretreatment in vivo, but this effect was abrogated by SB431542. These results collectively suggest that TGF-β1 could enhance cell survival by accelerating the DDR via Smad signaling and Lig4 expression. -- Highlights: •TGF-β1 pretreatment accelerates γ-radiation-induced DNA damage response. •TGF-β1-accelerated DNA damage response is dependent on Smad signaling and DNA Ligase IV. •TGF-β1 pretreatment protects epithelial cells from γ-radiation in vivo.

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

    Directory of Open Access Journals (Sweden)

    Jun Shimizu

    2013-01-01

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

  6. Influence of cell cycle on responses of MCF-7 cells to benzo[a]pyrene

    Directory of Open Access Journals (Sweden)

    Giddings Ian

    2011-06-01

    Full Text Available Abstract Background Benzo[a]pyrene (BaP is a widespread environmental genotoxic carcinogen that damages DNA by forming adducts. This damage along with activation of the aryl hydrocarbon receptor (AHR induces complex transcriptional responses in cells. To investigate whether human cells are more susceptible to BaP in a particular phase of the cell cycle, synchronised breast carcinoma MCF-7 cells were exposed to BaP. Cell cycle progression was analysed by flow cytometry, DNA adduct formation was assessed by 32P-postlabeling analysis, microarrays of 44K human genome-wide oligos and RT-PCR were used to detect gene expression (mRNA changes and Western blotting was performed to determine the expression of some proteins, including cytochrome P450 (CYP 1A1 and CYP1B1, which are involved in BaP metabolism. Results Following BaP exposure, cells evaded G1 arrest and accumulated in S-phase. Higher levels of DNA damage occurred in S- and G2/M- compared with G0/G1-enriched cultures. Genes that were found to have altered expression included those involved in xenobiotic metabolism, apoptosis, cell cycle regulation and DNA repair. Gene ontology and pathway analysis showed the involvement of various signalling pathways in response to BaP exposure, such as the Catenin/Wnt pathway in G1, the ERK pathway in G1 and S, the Nrf2 pathway in S and G2/M and the Akt pathway in G2/M. An important finding was that higher levels of DNA damage in S- and G2/M-enriched cultures correlated with higher levels of CYP1A1 and CYP1B1 mRNA and proteins. Moreover, exposure of synchronised MCF-7 cells to BaP-7,8-diol-9,10-epoxide (BPDE, the ultimate carcinogenic metabolite of BaP, did not result in significant changes in DNA adduct levels at different phases of the cell cycle. Conclusions This study characterised the complex gene response to BaP in MCF-7 cells and revealed a strong correlation between the varying efficiency of BaP metabolism and DNA damage in different phases of the cell

  7. Innate lymphoid cells and their role in immune response regulation

    Directory of Open Access Journals (Sweden)

    Bibiana Patricia Ruiz-Sánchez

    2017-10-01

    Full Text Available Innate lymphoid cells (ILCs are lymphocytes lacking antigen recognition receptors and become activated in response to cytokines and through microbe-associated molecular pattern (MAMP receptors. ILCs are found mainly in mucosal tissues and participate in the immune response against infections and in chronic inflammatory conditions. ILCs are divided in ILC-1, ILC-2 and ILC-3, and these cells have analogue functions to those of immune adaptive response lymphocytes Th1, Th2 and Th17. ILC-1 express T-bet, produce IFNγ, protect against infections with intracellular microorganisms and are related to inflammatory bowel disease immunopathology. ILC-2 express GATA3, produce IL-4, IL-5, IL-13 and amphiregulin, protect against parasitic infections and related to allergy and obesity immunopathology. ILC-3 express ROR(γt, produce IL-17 and IL-22, protect against fungal infections and contribute to tolerance to intestinal microbiota and intestinal repair. They are related to inflammatory bowel disease and psoriasis immunopathology. In general terms, ILCs maintain homeostasis and coadjuvate in the protection against infections.

  8. The circadian response of intrinsically photosensitive retinal ganglion cells.

    Directory of Open Access Journals (Sweden)

    Andrew J Zele

    Full Text Available Intrinsically photosensitive retinal ganglion cells (ipRGC signal environmental light level to the central circadian clock and contribute to the pupil light reflex. It is unknown if ipRGC activity is subject to extrinsic (central or intrinsic (retinal network-mediated circadian modulation during light entrainment and phase shifting. Eleven younger persons (18-30 years with no ophthalmological, medical or sleep disorders participated. The activity of the inner (ipRGC and outer retina (cone photoreceptors was assessed hourly using the pupil light reflex during a 24 h period of constant environmental illumination (10 lux. Exogenous circadian cues of activity, sleep, posture, caffeine, ambient temperature, caloric intake and ambient illumination were controlled. Dim-light melatonin onset (DLMO was determined from salivary melatonin assay at hourly intervals, and participant melatonin onset values were set to 14 h to adjust clock time to circadian time. Here we demonstrate in humans that the ipRGC controlled post-illumination pupil response has a circadian rhythm independent of external light cues. This circadian variation precedes melatonin onset and the minimum ipRGC driven pupil response occurs post melatonin onset. Outer retinal photoreceptor contributions to the inner retinal ipRGC driven post-illumination pupil response also show circadian variation whereas direct outer retinal cone inputs to the pupil light reflex do not, indicating that intrinsically photosensitive (melanopsin retinal ganglion cells mediate this circadian variation.

  9. Mesenchymal Stromal Cells Can Regulate the Immune Response in the Tumor Microenvironment

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    Alessandro Poggi

    2016-11-01

    Full Text Available The tumor microenvironment is a good target for therapy in solid tumors and hematological malignancies. Indeed, solid tumor cells’ growth and expansion can influence neighboring cells’ behavior, leading to a modulation of mesenchymal stromal cell (MSC activities and remodeling of extracellular matrix components. This leads to an altered microenvironment, where reparative mechanisms, in the presence of sub-acute inflammation, are not able to reconstitute healthy tissue. Carcinoma cells can undergo epithelial mesenchymal transition (EMT, a key step to generate metastasis; these mesenchymal-like cells display the functional behavior of MSC. Furthermore, MSC can support the survival and growth of leukemic cells within bone marrow participating in the leukemic cell niche. Notably, MSC can inhibit the anti-tumor immune response through either carcinoma-associated fibroblasts or bone marrow stromal cells. Experimental data have indicated their relevance in regulating cytolytic effector lymphocytes of the innate and adaptive arms of the immune system. Herein, we will discuss some of the evidence in hematological malignancies and solid tumors. In particular, we will focus our attention on the means by which it is conceivable to inhibit MSC-mediated immune suppression and trigger anti-tumor innate immunity.

  10. Induced pluripotent stem cells-derived myeloid-derived suppressor cells regulate the CD8+ T cell response

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    Daniel Joyce

    2018-05-01

    Full Text Available Myeloid-derived suppressor cells (MDSCs are markedly increased in cancer patients and tumor-bearing mice and promote tumor growth and survival by inhibiting host innate and adaptive immunity. In this study, we generated and characterized MDSCs from murine-induced pluripotent stem cells (iPSCs. The iPSCs were co-cultured with OP9 cells, stimulated with GM-CSF, and became morphologically heterologous under co-culturing with hepatic stellate cells. Allogeneic and OVA-specific antigen stimulation demonstrated that iPS-MDSCs have a T-cell regulatory function. Furthermore, a popliteal lymph node assay and autoimmune hepatitis model showed that iPS-MDSCs also regulate immune responsiveness in vivo and have a therapeutic effect against hepatitis. Taken together, our results demonstrated a method of generating functional MDSCs from iPSCs and highlighted the potential of iPS-MDSCs as a key cell therapy resource for transplantation and autoimmune diseases. Keywords: Myeloid-derived suppressor cells, Induced pluripotent stem cells, T cell response

  11. A probabilistic approach for the interpretation of RNA profiles as cell type evidence.

    Science.gov (United States)

    de Zoete, Jacob; Curran, James; Sjerps, Marjan

    2016-01-01

    DNA profiles can be used as evidence to distinguish between possible donors of a crime stain. In some cases, both the prosecution and the defence claim that the cell material was left by the suspect but they dispute which cell type was left behind. For example, in sexual offense cases the prosecution could claim that the sample contains semen cells where the defence argues that the sample contains skin cells. In these cases, traditional methods (e.g. a phosphatase test) can be used to examine the cell type contained in the sample. However, there are some drawbacks when using these methods. For instance, many of these techniques need to be carried out separately for each cell type and each of them requires part of the available sample, which reduces the amount that can be used for DNA analysis. Another option is messenger RNA (mRNA) evidence. mRNA expression levels vary among cell types and can be used to make (probability) statements about the cell type(s) present in a sample. Existing methods for the interpretation of RNA profiles as evidence for the presence of certain cell types aim at making categorical statements. Such statements limit the possibility to report the associated uncertainty. Some of these existing methods will be discussed. Most notably, a method based on a 'n/2' scoring rule (Lindenbergh et al.) and a method using marker values and cell type scoring thresholds (Roeder et al.). From a statistical point of view, a probabilistic approach is the most obvious choice. Two approaches (multinomial logistic regression and naïve Bayes') are suggested. All methods are compared, using two different datasets and several criteria regarding their ability to assess the evidential value of RNA profiles. We conclude that both the naïve Bayes' method and a method based on multinomial logistic regression, that produces a probabilistic statement as measure of the evidential value, are an important improvement of the existing methods. Besides a better performance

  12. Dendritic cell, monocyte and T cell activation and response to glatiramer acetate in multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, F; Hesse, D; Limborg, S

    2012-01-01

    , monocytes and dendritic cells (DC) in relation to disease activity in MS patients treated with GA. Methods: Flow cytometry was used to study the activation of CD4+ T cells and T cell subsets (CD25high and CD26high cells), monocytes and DCs in a cross-sectional study of 39 untreated and 29 GA-treated MS......Background: Treatment with glatiramer acetate (GA) modestly decreases disease activity in multiple sclerosis (MS). The mechanism of action is incompletely understood and differences in the response to treatment between individuals may exist. Objective: To study the activation of CD4+ T cells...... (Bonferroni-corrected p=0.0005). The hazard ratio of relapse was 1.32 (95% confidence interval 1.05–1.64) per 1% increase in CD40+ DCs. Patients treated with GA had fewer CD4+ T cells expressing surface markers associated with T helper type 1 effector responses and more CD4+ T cells expressing surface markers...

  13. Evidence for unfolded protein response activation in monocytes from individuals with alpha-1 antitrypsin deficiency.

    LENUS (Irish Health Repository)

    Carroll, Tomás P

    2010-04-15

    The hereditary disorder alpha-1 antitrypsin (AAT) deficiency results from mutations in the SERPINA1 gene and presents with emphysema in young adults and liver disease in childhood. The most common form of AAT deficiency occurs because of the Z mutation, causing the protein to fold aberrantly and accumulate in the endoplasmic reticulum (ER). This leads to ER stress and contributes significantly to the liver disease associated with the condition. In addition to hepatocytes, AAT is also synthesized by monocytes, neutrophils, and epithelial cells. In this study we show for the first time that the unfolded protein response (UPR) is activated in quiescent monocytes from ZZ individuals. Activating transcription factor 4, X-box binding protein 1, and a subset of genes involved in the UPR are increased in monocytes from ZZ compared with MM individuals. This contributes to an inflammatory phenotype with ZZ monocytes exhibiting enhanced cytokine production and activation of the NF-kappaB pathway when compared with MM monocytes. In addition, we demonstrate intracellular accumulation of AAT within the ER of ZZ monocytes. These are the first data showing that Z AAT protein accumulation induces UPR activation in peripheral blood monocytes. These findings change the current paradigm regarding lung inflammation in AAT deficiency, which up until now was derived from the protease-anti-protease hypothesis, but which now must include the exaggerated inflammatory response generated by accumulated aberrantly folded AAT in circulating blood cells.

  14. Low-Dose Ionizing Radiation Affects Mesenchymal Stem Cells via Extracellular Oxidized Cell-Free DNA: A Possible Mediator of Bystander Effect and Adaptive Response

    Directory of Open Access Journals (Sweden)

    V. A. Sergeeva

    2017-01-01

    Full Text Available We have hypothesized that the adaptive response to low doses of ionizing radiation (IR is mediated by oxidized cell-free DNA (cfDNA fragments. Here, we summarize our experimental evidence for this model. Studies involving measurements of ROS, expression of the NOX (superoxide radical production, induction of apoptosis and DNA double-strand breaks, antiapoptotic gene expression and cell cycle inhibition confirm this hypothesis. We have demonstrated that treatment of mesenchymal stem cells (MSCs with low doses of IR (10 cGy leads to cell death of part of cell population and release of oxidized cfDNA. cfDNA has the ability to penetrate into the cytoplasm of other cells. Oxidized cfDNA, like low doses of IR, induces oxidative stress, ROS production, ROS-induced oxidative modifications of nuclear DNA, DNA breaks, arrest of the cell cycle, activation of DNA reparation and antioxidant response, and inhibition of apoptosis. The MSCs pretreated with low dose of irradiation or oxidized cfDNA were equally effective in induction of adaptive response to challenge further dose of radiation. Our studies suggest that oxidized cfDNA is a signaling molecule in the stress signaling that mediates radiation-induced bystander effects and that it is an important component of the development of radioadaptive responses to low doses of IR.

  15. Human dental pulp cells exhibit bone cell-like responsiveness to fluid shear stress.

    Science.gov (United States)

    Kraft, David Christian Evar; Bindslev, Dorth Arenholt; Melsen, Birte; Klein-Nulend, Jenneke

    2011-02-01

    For engineering bone tissue to restore, for example, maxillofacial defects, mechanosensitive cells are needed that are able to conduct bone cell-specific functions, such as bone remodelling. Mechanical loading affects local bone mass and architecture in vivo by initiating a cellular response via loading-induced flow of interstitial fluid. After surgical removal of ectopically impacted third molars, human dental pulp tissue is an easily accessible and interesting source of cells for mineralized tissue engineering. The aim of this study was to determine whether human dental pulp-derived cells (DPC) are responsive to mechanical loading by pulsating fluid flow (PFF) upon stimulation of mineralization in vitro. Human DPC were incubated with or without mineralization medium containing differentiation factors for 3 weeks. Cells were subjected to 1-h PFF (0.7 ± 0.3 Pa, 5 Hz) and the response was quantified by measuring nitric oxide (NO) and prostaglandin E₂ (PGE₂) production, and gene expression of cyclooxygenase (COX)-1 and COX-2. We found that DPC are intrinsically mechanosensitive and, like osteogenic cells, respond to PFF-induced fluid shear stress. PFF stimulated NO and PGE₂ production, and up-regulated COX-2 but not COX-1 gene expression. In DPC cultured under mineralizing conditions, the PFF-induced NO, but not PGE₂, production was significantly enhanced. These data suggest that human DPC, like osteogenic cells, acquire responsiveness to pulsating fluid shear stress in mineralizing conditions. Thus DPC might be able to perform bone-like functions during mineralized tissue remodeling in vivo, and therefore provide a promising new tool for mineralized tissue engineering to restore, for example, maxillofacial defects.

  16. The Importance of the Nurse Cells and Regulatory Cells in the Control of T Lymphocyte Responses

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    María Guadalupe Reyes García

    2013-01-01

    Full Text Available T lymphocytes from the immune system are bone marrow-derived cells whose development and activities are carefully supervised by two sets of accessory cells. In the thymus, the immature young T lymphocytes are engulfed by epithelial “nurse cells” and retained in vacuoles, where most of them (95% are negatively selected and removed when they have an incomplete development or express high affinity autoreactive receptors. The mature T lymphocytes that survive to this selection process leave the thymus and are controlled in the periphery by another subpopulation of accessory cells called “regulatory cells,” which reduce any excessive immune response and the risk of collateral injuries to healthy tissues. By different times and procedures, nurse cells and regulatory cells control both the development and the functions of T lymphocyte subpopulations. Disorders in the T lymphocytes development and migration have been observed in some parasitic diseases, which disrupt the thymic microenvironment of nurse cells. In other cases, parasites stimulate rather than depress the functions of regulatory T cells decreasing T-mediated host damages. This paper is a short review regarding some features of these accessory cells and their main interactions with T immature and mature lymphocytes. The modulatory role that neurotransmitters and hormones play in these interactions is also revised.

  17. Evidence of endothelial inflammation, T cell activation, and T cell reallocation in uncomplicated Plasmodium falciparum malaria

    DEFF Research Database (Denmark)

    Elhassan, I M; Hviid, L; Satti, G

    1994-01-01

    endothelium. We measured plasma levels of soluble markers of endothelial inflammation and T cell activation in 32 patients suffering from acute, uncomplication P. falciparum malaria, as well as in 10 healthy, aparasitemic control donors. All donors were residents of a malaria-endemic area of Eastern State...... Sudan. In addition, we measured the T cell surface expression of the interleukin-2 receptor (CD25) and the lymphocyte function-associated antigen (LFA-1; CD11a/CD18). We found that the plasma levels of all inflammation and activation markers were significantly increased in the malaria patients compared...... with the control donors. In addition, we found a disease-induced depletion of T cells with high expression of the LFA-1 antigen, particularly in the CD4+ subset. The results obtained provide further support for the hypothesis of T cell reallocation to inflamed endothelium in acute P. falciparum malaria....

  18. Genetic analysis of human traits in vitro: drug response and gene expression in lymphoblastoid cell lines.

    Directory of Open Access Journals (Sweden)

    Edwin Choy

    2008-11-01

    Full Text Available Lymphoblastoid cell lines (LCLs, originally collected as renewable sources of DNA, are now being used as a model system to study genotype-phenotype relationships in human cells, including searches for QTLs influencing levels of individual mRNAs and responses to drugs and radiation. In the course of attempting to map genes for drug response using 269 LCLs from the International HapMap Project, we evaluated the extent to which biological noise and non-genetic confounders contribute to trait variability in LCLs. While drug responses could be technically well measured on a given day, we observed significant day-to-day variability and substantial correlation to non-genetic confounders, such as baseline growth rates and metabolic state in culture. After correcting for these confounders, we were unable to detect any QTLs with genome-wide significance for drug response. A much higher proportion of variance in mRNA levels may be attributed to non-genetic factors (intra-individual variance--i.e., biological noise, levels of the EBV virus used to transform the cells, ATP levels than to detectable eQTLs. Finally, in an attempt to improve power, we focused analysis on those genes that had both detectable eQTLs and correlation to drug response; we were unable to detect evidence that eQTL SNPs are convincingly associated with drug response in the model. While LCLs are a promising model for pharmacogenetic experiments, biological noise and in vitro artifacts may reduce power and have the potential to create spurious association due to confounding.

  19. Leukemia-associated activating mutation of Flt3 expands dendritic cells and alters T cell responses.

    Science.gov (United States)

    Lau, Colleen M; Nish, Simone A; Yogev, Nir; Waisman, Ari; Reiner, Steven L; Reizis, Boris

    2016-03-07

    A common genetic alteration in acute myeloid leukemia is the internal tandem duplication (ITD) in FLT3, the receptor for cytokine FLT3 ligand (FLT3L). Constitutively active FLT3-ITD promotes the expansion of transformed progenitors, but also has pleiotropic effects on hematopoiesis. We analyzed the effect of FLT3-ITD on dendritic cells (DCs), which express FLT3 and can be expanded by FLT3L administration. Pre-leukemic mice with the Flt3(ITD) knock-in allele manifested an expansion of classical DCs (cDCs) and plasmacytoid DCs. The expansion originated in DC progenitors, was cell intrinsic, and was further enhanced in Flt3(ITD/ITD) mice. The mutation caused the down-regulation of Flt3 on the surface of DCs and reduced their responsiveness to Flt3L. Both canonical Batf3-dependent CD8(+) cDCs and noncanonical CD8(+) cDCs were expanded and showed specific alterations in their expression profiles. Flt3(ITD) mice showed enhanced capacity to support T cell proliferation, including a cell-extrinsic expansion of regulatory T (T reg) cells. Accordingly, these mice restricted alloreactive T cell responses during graft-versus-host reaction, but failed to control autoimmunity without T reg cells. Thus, the FLT3-ITD mutation directly affects DC development, indirectly modulating T cell homeostasis and supporting T reg cell expansion. We hypothesize that this effect of FLT3-ITD might subvert immunosurveillance and promote leukemogenesis in a cell-extrinsic manner. © 2016 Lau et al.

  20. Cytomegalovirus-specific T-cell responses and viral replication in kidney transplant recipients

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    Sester Urban

    2008-06-01

    Full Text Available Abstract Background Cytomegalovirus (CMV seronegative recipients (R- of kidney transplants (KT from seropositive donors (D+ are at higher risk for CMV replication and ganciclovir(GCV-resistance than CMV R(+. We hypothesized that low CMV-specific T-cell responses are associated with increased risk of CMV replication in R(+-patients with D(+ or D(- donors. Methods We prospectively evaluated 73 consecutive KT-patients [48 R(+, 25 D(+R(-] undergoing routine testing for CMV replication as part of a preemptive strategy. We compared CMV-specific interferon-γ (IFN-γ responses of CD4+CD3+ lymphocytes in peripheral blood mononuclear cells (PBMC using three different antigen preparation (CMV-lysate, pp72- and pp65-overlapping peptide pools using intracellular cytokine staining and flow cytometry. Results Median CD4+ and CD8+T-cell responses to CMV-lysate, pp72- and pp65-overlapping peptide pools were lower in D(+R(- than in R(+patients or in non-immunosuppressed donors. Comparing subpopulations we found that CMV-lysate favored CD4+- over CD8+-responses, whereas the reverse was observed for pp72, while pp65-CD4+- and -CD8+-responses were similar. Concurrent CMV replication in R(+-patients was associated with significantly lower T-cell responses (pp65 median CD4+ 0.00% vs. 0.03%, p = 0.001; CD8+ 0.01% vs. 0.03%; p = 0.033. Receiver operated curve analysis associated CMV-pp65 CD4+ responses of > 0.03% in R(+-patients with absence of concurrent (p = 0.003 and future CMV replication in the following 8 weeks (p = 0.036. GCV-resistant CMV replication occurred in 3 R(+-patients (6.3% with pp65- CD4+ frequencies Conclusion The data suggest that pp65-specific CD4+ T-cells might be useful to identify R(+-patients at increased risk of CMV replication. Provided further corroborating evidence, CMV-pp65 CD4+ responses above 0.03% in PBMCs of KT patients under stable immunosuppression are associated with lower risk of concurrent and future CMV replication during the

  1. Evidence for universality and cultural variation of differential emotion response patterning.

    Science.gov (United States)

    Scherer, K R; Wallbott, H G

    1994-02-01

    The major controversy concerning psychobiological universality of differential emotion patterning versus cultural relativity of emotional experience is briefly reviewed. Data from a series of cross-cultural questionnaire studies in 37 countries on 5 continents are reported and used to evaluate the respective claims of the proponents in the debate. Results show highly significant main effects and strong effect sizes for the response differences across 7 major emotions (joy, fear, anger, sadness, disgust, shame, and guilt). Profiles of cross-culturally stable differences among the emotions with respect to subjective feeling, physiological symptoms, and expressive behavior are also reported. The empirical evidence is interpreted as supporting theories that postulate both a high degree of universality of differential emotion patterning and important cultural differences in emotion elicitation, regulation, symbolic representation, and social sharing.

  2. Reviewing the current evidence supporting early B-cells as the cellular origin of Merkel cell carcinoma.

    Science.gov (United States)

    Sauer, C M; Haugg, A M; Chteinberg, E; Rennspiess, D; Winnepenninckx, V; Speel, E-J; Becker, J C; Kurz, A K; Zur Hausen, A

    2017-08-01

    Merkel cell carcinoma (MCC) is a highly malignant skin cancer characterized by early metastases and poor survival. Although MCC is a rare malignancy, its incidence is rapidly increasing in the U.S. and Europe. The discovery of the Merkel cell polyomavirus (MCPyV) has enormously impacted our understanding of its etiopathogenesis and biology. MCCs are characterized by trilinear differentiation, comprising the expression of neuroendocrine, epithelial and B-lymphoid lineage markers. To date, it is generally accepted that the initial assumption of MCC originating from Merkel cells (MCs) is unlikely. This is owed to their post-mitotic character, absence of MCPyV in MCs and discrepant protein expression pattern in comparison to MCC. Evidence from mouse models suggests that epidermal/dermal stem cells might be of cellular origin in MCC. The recently formulated hypothesis of MCC originating from early B-cells is based on morphology, the consistent expression of early B-cell lineage markers and the finding of clonal immunoglobulin chain rearrangement in MCC cells. In this review we elaborate on the cellular ancestry of MCC, the identification of which could pave the way for novel and more effective therapeutic regimens. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Endoplasmic Reticulum Stress, Unfolded Protein Response, and Cancer Cell Fate

    Directory of Open Access Journals (Sweden)

    Marco Corazzari

    2017-04-01

    Full Text Available Perturbation of endoplasmic reticulum (ER homeostasis results in a stress condition termed “ER stress” determining the activation of a finely regulated program defined as unfolded protein response (UPR and whose primary aim is to restore this organelle’s physiological activity. Several physiological and pathological stimuli deregulate normal ER activity causing UPR activation, such as hypoxia, glucose shortage, genome instability, and cytotoxic compounds administration. Some of these stimuli are frequently observed during uncontrolled proliferation of transformed cells, resulting in tumor core formation and stage progression. Therefore, it is not surprising that ER stress is usually induced during solid tumor development and stage progression, becoming an hallmark of such malignancies. Several UPR components are in fact deregulated in different tumor types, and accumulating data indicate their active involvement in tumor development/progression. However, although the UPR program is primarily a pro-survival process, sustained and/or prolonged stress may result in cell death induction. Therefore, understanding the mechanism(s regulating the cell survival/death decision under ER stress condition may be crucial in order to specifically target tumor cells and possibly circumvent or overcome tumor resistance to therapies. In this review, we discuss the role played by the UPR program in tumor initiation, progression and resistance to therapy, highlighting the recent advances that have improved our understanding of the molecular mechanisms that regulate the survival/death switch.

  4. The Transcriptional Coactivator Bob1 Is Associated With Pathologic B Cell Responses in Autoimmune Tissue Inflammation

    NARCIS (Netherlands)

    Levels, Maria J.; Van Tok, Melissa N.; Cantaert, Tineke; Canete, Juan D.; Kroese, Frans G. M.; Germar, Kristine; Spits, Hergen; Baeten, Dominique L. P.; Yeremenko, Nataliya G.

    Objective. The molecular mechanisms steering abnormal B cell responses in autoimmune diseases remain poorly understood. We undertook this study to identify molecular switches controlling pathologic B cell responses in rheumatoid arthritis (RA). Methods. Candidate molecules were identified by gene

  5. Evidence of a Redox-Dependent Regulation of Immune Responses to Exercise-Induced Inflammation

    Directory of Open Access Journals (Sweden)

    Alexandra Sakelliou

    2016-01-01

    Full Text Available We used thiol-based antioxidant supplementation (n-acetylcysteine, NAC to determine whether immune mobilisation following skeletal muscle microtrauma induced by exercise is redox-sensitive in healthy humans. According to a two-trial, double-blind, crossover, repeated measures design, 10 young men received either placebo or NAC (20 mg/kg/day immediately after a muscle-damaging exercise protocol (300 eccentric contractions and for eight consecutive days. Blood sampling and performance assessments were performed before exercise, after exercise, and daily throughout recovery. NAC reduced the decline of reduced glutathione in erythrocytes and the increase of plasma protein carbonyls, serum TAC and erythrocyte oxidized glutathione, and TBARS and catalase activity during recovery thereby altering postexercise redox status. The rise of muscle damage and inflammatory markers (muscle strength, creatine kinase activity, CRP, proinflammatory cytokines, and adhesion molecules was less pronounced in NAC during the first phase of recovery. The rise of leukocyte and neutrophil count was decreased by NAC after exercise. Results on immune cell subpopulations obtained by flow cytometry indicated that NAC ingestion reduced the exercise-induced rise of total macrophages, HLA+ macrophages, and 11B+ macrophages and abolished the exercise-induced upregulation of B lymphocytes. Natural killer cells declined only in PLA immediately after exercise. These results indicate that thiol-based antioxidant supplementation blunts immune cell mobilisation in response to exercise-induced inflammation suggesting that leukocyte mobilization may be under redox-dependent regulation.

  6. Group differences in physician responses to handheld presentation of clinical evidence: a verbal protocol analysis

    Directory of Open Access Journals (Sweden)

    Pavlovic Nada J

    2007-07-01

    Full Text Available Abstract Background To identify individual differences in physicians' needs for the presentation of evidence resources and preferences for mobile devices. Methods Within-groups analysis of responses to semi-structured interviews. Interviews consisted of using prototypes in response to task-based scenarios. The prototypes were implemented on two different form factors: a tablet style PC and a pocketPC. Participants were from three user groups: general internists, family physicians and medicine residents, and from two different settings: urban and semi-urban. Verbal protocol analysis, which consists of coding utterances, was conducted on the transcripts of the testing sessions. Statistical relationships were investigated between staff physicians' and residents' background variables, self-reported experiences with the interfaces, and verbal code frequencies. Results 47 physicians were recruited from general internal medicine, family practice clinics and a residency training program. The mean age of participants was 42.6 years. Physician specialty had a greater effect on device and information-presentation preferences than gender, age, setting or previous technical experience. Family physicians preferred the screen size of the tablet computer and were less concerned about its portability. Residents liked the screen size of the tablet, but preferred the portability of the pocketPC. Internists liked the portability of the pocketPC, but saw less advantage to the large screen of the tablet computer (F[2,44] = 4.94, p = .012. Conclusion Different types of physicians have different needs and preferences for evidence-based resources and handheld devices. This study shows how user testing can be incorporated into the process of design to inform group-based customization.

  7. Light Influences How the Fungal Toxin Deoxynivalenol Affects Plant Cell Death and Defense Responses

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    Khairul I. Ansari

    2014-02-01

    Full Text Available The Fusarium mycotoxin deoxynivalenol (DON can cause cell death in wheat (Triticum aestivum, but can also reduce the level of cell death caused by heat shock in Arabidopsis (Arabidopsis thaliana cell cultures. We show that 10 μg mL−1 DON does not cause cell death in Arabidopsis cell cultures, and its ability to retard heat-induced cell death is light dependent. Under dark conditions, it actually promoted heat-induced cell death. Wheat cultivars differ in their ability to resist this toxin, and we investigated if the ability of wheat to mount defense responses was light dependent. We found no evidence that light affected the transcription of defense genes in DON-treated roots of seedlings of two wheat cultivars, namely cultivar CM82036 that is resistant to DON-induced bleaching of spikelet tissue and cultivar Remus that is not. However, DON treatment of roots led to genotype-dependent and light-enhanced defense transcript accumulation in coleoptiles. Wheat transcripts encoding a phenylalanine ammonia lyase (PAL gene (previously associated with Fusarium resistance, non-expressor of pathogenesis-related genes-1 (NPR1 and a class III plant peroxidase (POX were DON-upregulated in coleoptiles of wheat cultivar CM82036 but not of cultivar Remus, and DON-upregulation of these transcripts in cultivar CM82036 was light enhanced. Light and genotype-dependent differences in the DON/DON derivative content of coleoptiles were also observed. These results, coupled with previous findings regarding the effect of DON on plants, show that light either directly or indirectly influences the plant defense responses to DON.

  8. Genetic evidence for the association between the early growth response 3 (EGR3 gene and schizophrenia.

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    Full Text Available Recently, two genome scan meta-analysis studies have found strong evidence for the association of loci on chromosome 8p with schizophrenia. The early growth response 3 (EGR3 gene located in chromosome 8p21.3 was also found to be involved in the etiology of schizophrenia. However, subsequent studies failed to replicate this finding. To investigate the genetic role of EGR3 in Chinese patients, we genotyped four SNPs (average interval ∼2.3 kb in the chromosome region of EGR3 in 470 Chinese schizophrenia patients and 480 healthy control subjects. The SNP rs35201266 (located in intron 1 of EGR3 showed significant differences between cases and controls in both genotype frequency distribution (P = 0.016 and allele frequency distribution (P = 0.009. Analysis of the haplotype rs35201266-rs3750192 provided significant evidence for association with schizophrenia (P = 0.0012; a significant difference was found for the common haplotype AG (P = 0.0005. Furthermore, significant associations were also found in several other two-, and three-SNP tests of haplotype analyses. The meta-analysis revealed a statistically significant association between rs35201266 and schizophrenia (P = 0.0001. In summary, our study supports the association of EGR3 with schizophrenia in our Han Chinese sample, and further functional exploration of the EGR3 gene will contribute to the molecular basis for the complex network underlying schizophrenia pathogenesis.

  9. MMP19 is essential for T cell development and T cell-mediated cutaneous immune responses

    Czech Academy of Sciences Publication Activity Database

    Beck, Inken; Ruckert, R.; Brandt, K.; Mueller, M.S.; Sadowski, T.; Brauer, R.; Schirmacher, P.; Mentlein, R.; Sedláček, Radislav

    2008-01-01

    Roč. 3, č. 6 (2008), e2343-e2343 E-ISSN 1932-6203 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50520701 Keywords : matrix metalloproteinase * T cell * immune response Subject RIV: EB - Genetics ; Molecular Biology

  10. Response of hematopoietic stem cells to ionizing radiation

    International Nuclear Information System (INIS)

    Simonnet, A.

    2008-12-01

    experiment that a single TPO administration rescued the IR-impaired reconstitution capacity of HSCs early after exposure. In addition, the use of marrow cells from transgenic ubiquitous luciferase-expressing donors combined with bioluminescence imaging technology provided a valuable strategy that allowed visualizing HSC homing of TPO-treated compared to untreated irradiated donors, and enabled the identification of a preferential cellular expansion sites which were inaccessible to investigation in most studies. Finally, we observed that TPO injection right after irradiation considerably attenuates IR-induced long-term injury to the stem/progenitor compartment. Altogether, these data provide novel insights in the cellular response of HSC to IR and the beneficial effects of TPO administration to these cells. (author)

  11. How entorhinal grid cells may learn multiple spatial scales from a dorsoventral gradient of cell response rates in a self-organizing map.

    Directory of Open Access Journals (Sweden)

    Stephen Grossberg

    Full Text Available Place cells in the hippocampus of higher mammals are critical for spatial navigation. Recent modeling clarifies how this may be achieved by how grid cells in the medial entorhinal cortex (MEC input to place cells. Grid cells exhibit hexagonal grid firing patterns across space in multiple spatial scales along the MEC dorsoventral axis. Signals from grid cells of multiple scales combine adaptively to activate place cells that represent much larger spaces than grid cells. But how do grid cells learn to fire at multiple positions that form a hexagonal grid, and with spatial scales that increase along the dorsoventral axis? In vitro recordings of medial entorhinal layer II stellate cells have revealed subthreshold membrane potential oscillations (MPOs whose temporal periods, and time constants of excitatory postsynaptic potentials (EPSPs, both increase along this axis. Slower (faster subthreshold MPOs and slower (faster EPSPs correlate with larger (smaller grid spacings and field widths. A self-organizing map neural model explains how the anatomical gradient of grid spatial scales can be learned by cells that respond more slowly along the gradient to their inputs from stripe cells of multiple scales, which perform linear velocity path integration. The model cells also exhibit MPO frequencies that covary with their response rates. The gradient in intrinsic rhythmicity is thus not compelling evidence for oscillatory interference as a mechanism of grid cell firing. A response rate gradient combined with input stripe cells that have normalized receptive fields can reproduce all known spatial and temporal properties of grid cells along the MEC dorsoventral axis. This spatial gradient mechanism is homologous to a gradient mechanism for temporal learning in the lateral entorhinal cortex and its hippocampal projections. Spatial and temporal representations may hereby arise from homologous mechanisms, thereby embodying a mechanistic "neural relativity" that

  12. Lysosomal membrane permeabilization in cell death: new evidence and implications for health and disease.

    Science.gov (United States)

    Serrano-Puebla, Ana; Boya, Patricia

    2016-05-01

    Recent studies have demonstrated that, in addition to their central role in cellular catabolic reactions, lysosomes are implicated in many cellular processes, including metabolism, membrane repair, and cell death. Lysosomal membrane permeabilization (LMP) has emerged as a pathway by which cell demise is regulated under physiological conditions and contributes to cell death in many pathological situations. Here, we review the latest evidence on LMP-mediated cell death, the upstream and downstream signals involved, and the role of LMP in the normal physiology of organisms. We also discuss the contributions of lysosomal damage and LMP to the pathogenic features of several disease states, such as lysosomal storage disorders and other neurodegenerative conditions. © 2015 New York Academy of Sciences.

  13. Cell specificity of the cytoplasmic Ca2+ response to tolbutamide is impaired in beta-cells from hyperglycemic mice

    DEFF Research Database (Denmark)

    Gustavsson, Natalia; Larsson-Nyrén, Gerd; Lindström, Per

    2006-01-01

    We recently reported that the timing and magnitude of the nutrient-induced Ca(2+) response are specific and reproducible for each isolated beta-cell. We have now used tolbutamide and arginine to test if the cell specificity exists also for the response to non-nutrient stimulation of beta-cells an...

  14. 'Faceness' and affectivity: evidence for genetic contributions to distinct components of electrocortical response to human faces.

    Science.gov (United States)

    Shannon, Robert W; Patrick, Christopher J; Venables, Noah C; He, Sheng

    2013-12-01

    The ability to recognize a variety of different human faces is undoubtedly one of the most important and impressive functions of the human perceptual system. Neuroimaging studies have revealed multiple brain regions (including the FFA, STS, OFA) and electrophysiological studies have identified differing brain event-related potential (ERP) components (e.g., N170, P200) possibly related to distinct types of face information processing. To evaluate the heritability of ERP components associated with face processing, including N170, P200, and LPP, we examined ERP responses to fearful and neutral face stimuli in monozygotic (MZ) and dizygotic (DZ) twins. Concordance levels for early brain response indices of face processing (N170, P200) were found to be stronger for MZ than DZ twins, providing evidence of a heritable basis to each. These findings support the idea that certain key neural mechanisms for face processing are genetically coded. Implications for understanding individual differences in recognition of facial identity and the emotional content of faces are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Culture modulates the brain response to human expressions of emotion: electrophysiological evidence.

    Science.gov (United States)

    Liu, Pan; Rigoulot, Simon; Pell, Marc D

    2015-01-01

    To understand how culture modulates on-line neural responses to social information, this study compared how individuals from two distinct cultural groups, English-speaking North Americans and Chinese, process emotional meanings of multi-sensory stimuli as indexed by both behaviour (accuracy) and event-related potential (N400) measures. In an emotional Stroop-like task, participants were presented face-voice pairs expressing congruent or incongruent emotions in conditions where they judged the emotion of one modality while ignoring the other (face or voice focus task). Results indicated that while both groups were sensitive to emotional differences between channels (with lower accuracy and higher N400 amplitudes for incongruent face-voice pairs), there were marked group differences in how intruding facial or vocal cues affected accuracy and N400 amplitudes, with English participants showing greater interference from irrelevant faces than Chinese. Our data illuminate distinct biases in how adults from East Asian versus Western cultures process socio-emotional cues, supplying new evidence that cultural learning modulates not only behaviour, but the neurocognitive response to different features of multi-channel emotion expressions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Strategic human resource management and corporate social responsibility: Evidence from Emerging Markets

    Directory of Open Access Journals (Sweden)

    Talita Rosolen

    2016-09-01

    Full Text Available Corporate social responsibility practices are increasingly being adopted and legitimized in business and they impact the strategic and operational levels in various areas. The integration of these criteria and practices in the strategic management involves many factors, and human resource management is an essential aspect for the accomplishment of such initiative. Thus, this paper associates the relationship among corporate social responsibility (CSR various dimensions (strategic, ethical, social and environmental and strategic human resource management (SHRM in companies operating in Brazil. We also aim to identify whether there is impact of other aspects on this relationship, namely: size, industry and company internationalization level (if national or multinational. Results show evidence that ethical CSR can be associated to SHRM. Environmental CSR showed marginal relation, and social and strategic CSR presented no significant association. Those results emphasize the need to further develop strategic actions of CSR into human resource management in emerging markets. Managers can also benefit from those findings, as it is possible to have a broad view of limitations and opportunities regarding the role played by human resource management in CSR.

  17. Sustainable Development and Corporate Social Responsibility in Sub-Saharan Africa: Evidence from Industries in Cameroon

    Directory of Open Access Journals (Sweden)

    Oyewole Simon Oginni

    2016-05-01

    Full Text Available Present technological innovations and social organizations continue to impose risks and limitations on the efficient performance of the biosphere. Human activities have increasingly short-lived sustainable natural endowments, to the extent that, the multiplier effects have ripples beyond the traditional benefits of economic production and consumption. Therefore, this study addressed practical concerns on how industries in Sub-Saharan Africa promote sustainable development in their corporate social responsibility models, using industries in Cameroon as a case study; it examined economic, social, and environmental components of sustainable development and corporate social responsibility (CSR. Our sample consists of 335 business enterprises from the last Censure Survey of Enterprises in Cameroon. The study adopted a systematic analysis through the Adjusted Residual Test, and the Phi and Cramer’s V tests. Findings revealed that industries in Cameroon prioritize environmental and social dimensions over economic dimensions. However, a few large enterprises implement a broad CSR that promotes sustainable business practices, whereas smaller ones do not; industries in Cameroon implement environmental dimensions of CSR as a safe buffer and a social dimension as philanthropy. Hence, there is no concrete evidence that industries promote sustainable development via CSR in Cameroon. The implementation of a sustainable business model is a precondition for promoting sustainable development via CSR. Industries should realize the concrete value in implementing a sustainable business model that helps to adjust to the complex and increasingly changing business environment.

  18. Human Bronchial Epithelial Cell Response to Heavy Particle Exposure

    Science.gov (United States)

    Story, Michael; Ding, Liang-Hao; Minna, John; Park, Seong-mi; Peyton, Michael; Larsen, Jill

    2012-07-01

    A battery of non-oncogenically immortalized human bronchial epithelial cells (HBECs) are being used to examine the molecular changes that lead to lung carcinogenesis after exposure to heavy particles found in the free space environment. The goal is to ultimately identify biomarkers of radioresponse that can be used for prediction of carcinogenic risk for fatal lung cancer. Our initial studies have focused on the cell line HBEC3 KT and the isogenic variant HBEC3 KTR53, which overexpresses the RASv12 mutant and where p53 has been knocked down by shRNA, and is considered to be a more oncogenically progressed variant. We have previously described the response of HBEC3 KT at the cellular and molecular level, however, the focus here is on the rate of cellular transformation after HZE radiation exposure and the molecular changes in transformed cells. When comparing the two cell lines we find that there is a maximum rate of cellular transformation at 0.25 Gy when cells are exposed to 1 GeV Fe particles, and, for the HBEC3 KTR53 there are multiple pathways upregulated that promote anchorage independent growth including the mTOR pathway, the TGF-1 pathway, RhoA signaling and the ERK/MAPK pathway as early as 2 weeks after radiation. This does not occur in the HBEC3 KT cell line. Transformed HBEC3 KT cells do not show any morphologic or phenotypic changes when grown as cell cultures. HBEC3 KTR53 cells on the other hand show substantial changes in morphology from a cobblestone epithelial appearance to a mesenchymal appearance with a lack of contact inhibition. This epithelial to mesenchymal change in morphology is accompanied by the expression of vimentin and a reduction in the expression of E-cadherin, which are hallmarks of epithelial to mesenchymal transition. Interestingly, for HBEC3 KT transformed cells there are no mutations in the p53 gene, 2 of 15 clones were found to be heterozygous for the RASV12 mutation, and 3 of 15 clones expressed high levels of BigH3, a TGFB-responsive

  19. Helminth-induced regulatory T cells and suppression of allergic responses.

    Science.gov (United States)

    Logan, Jayden; Navarro, Severine; Loukas, Alex; Giacomin, Paul

    2018-05-28

    Infection with helminths has been associated with lower rates of asthma and other allergic diseases. This has been attributed, in part, to the ability of helminths to induce regulatory T cells that suppress inappropriate immune responses to allergens. Recent compelling evidence suggests that helminths may promote regulatory T cell expansion or effector functions through either direct (secretion of excretory/secretory molecules) or indirect mechanisms (regulation of the microbiome). This review will discuss key findings from human immunoepidemiological observations, studies using animal models of disease, and clinical trials with live worm infections, discussing the therapeutic potential for worms and their secreted products for treating allergic inflammation. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

  20. Hydrogenated amorphous silicon coatings may modulate gingival cell response

    Science.gov (United States)

    Mussano, F.; Genova, T.; Laurenti, M.; Munaron, L.; Pirri, C. F.; Rivolo, P.; Carossa, S.; Mandracci, P.

    2018-04-01

    Silicon-based materials present a high potential for dental implant applications, since silicon has been proven necessary for the correct bone formation in animals and humans. Notably, the addition of silicon is effective to enhance the bioactivity of hydroxyapatite and other biomaterials. The present work aims to expand the knowledge of the role exerted by hydrogen in the biological interaction of silicon-based materials, comparing two hydrogenated amorphous silicon coatings, with different hydrogen content, as means to enhance soft tissue cell adhesion. To accomplish this task, the films were produced by plasma enhanced chemical vapor deposition (PECVD) on titanium substrates and their surface composition and hydrogen content were analyzed by means of X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectrophotometry (FTIR) respectively. The surface energy and roughness were measured through optical contact angle analysis (OCA) and high-resolution mechanical profilometry respectively. Coated surfaces showed a slightly lower roughness, compared to bare titanium samples, regardless of the hydrogen content. The early cell responses of human keratinocytes and fibroblasts were tested on the above mentioned surface modifications, in terms of cell adhesion, viability and morphometrical assessment. Films with lower hydrogen content were endowed with a surface energy comparable to the titanium surfaces. Films with higher hydrogen incorporation displayed a lower surface oxidation and a considerably lower surface energy, compared to the less hydrogenated samples. As regards mean cell area and focal adhesion density, both a-Si coatings influenced fibroblasts, but had no significant effects on keratinocytes. On the contrary, hydrogen-rich films increased manifolds the adhesion and viability of keratinocytes, but not of fibroblasts, suggesting a selective biological effect on these cells.

  1. Induction of non-responsiveness in human allergen-specific type 2 T helper cells.

    Science.gov (United States)

    Yssel, H; Fasler, S; Lamb, J; de Vries, J E

    1994-12-01

    Activation of allergen-reactive human T helper (Th)2 cells in the absence of professional antigen-presenting cells, induces non-responsiveness or anergy in these cells in vitro. This induction of anergy is accompanied by phenotypic modulation and altered cytokine production. Furthermore, peptide-treated Th2 cells fail to provide B-cell help for IgE synthesis. Recent studies indicate that impaired signal transduction via the T-cell receptor may account for the lack of responsiveness to antigenic stimulation. Here, we review present knowledge on the cell biology of non-responsive or anergic Th2 cells.

  2. Potassium-chloride cotransporter 3 interacts with Vav2 to synchronize the cell volume decrease response with cell protrusion dynamics.

    Directory of Open Access Journals (Sweden)

    Adèle Salin-Cantegrel

    Full Text Available Loss-of-function of the potassium-chloride cotransporter 3 (KCC3 causes hereditary motor and sensory neuropathy with agenesis of the corpus callosum (HMSN/ACC, a severe neurodegenerative disease associated with defective midline crossing of commissural axons in the brain. Conversely, KCC3 over-expression in breast, ovarian and cervical cancer is associated with enhanced tumor cell malignancy and invasiveness. We identified a highly conserved proline-rich sequence within the C-terminus of the cotransporter which when mutated leads to loss of the KCC3-dependent regulatory volume decrease (RVD response in Xenopus Laevis oocytes. Using SH3 domain arrays, we found that this poly-proline motif is a binding site for SH3-domain containing proteins in vitro. This approach identified the guanine nucleotide exchange factor (GEF Vav2 as a candidate partner for KCC3. KCC3/Vav2 physical interaction was confirmed using GST-pull down assays and immuno-based experiments. In cultured cervical cancer cells, KCC3 co-localized with the active form of Vav2 in swelling-induced actin-rich protruding sites and within lamellipodia of spreading and migrating cells. These data provide evidence of a molecular and functional link between the potassium-chloride co-transporters and the Rho GTPase-dependent actin remodeling machinery in RVD, cell spreading and cell protrusion dynamics, thus providing new insights into KCC3's involvement in cancer cell malignancy and in corpus callosum agenesis in HMSN/ACC.

  3. Cell phone use and parotid salivary gland alterations: no molecular evidence.

    Science.gov (United States)

    de Souza, Fabrício T A; Correia-Silva, Jeane F; Ferreira, Efigênia F; Siqueira, Elisa C; Duarte, Alessandra P; Gomez, Marcus Vinícius; Gomez, Ricardo S; Gomes, Carolina C

    2014-07-01

    The association between cell phone use and the development of parotid tumors is controversial. Because there is unequivocal evidence that the microenvironment is important for tumor formation, we investigated in the parotid glands whether cell phone use alters the expression of gene products related to cellular stress. We used the saliva produced by the parotid glands of 62 individuals to assess molecular alterations compatible with cellular stress, comparing the saliva from the gland exposed to cell phone radiation (ipsilateral) to the saliva from the opposite, unexposed parotid gland (contralateral) of each individual. We compared salivary flow, total protein concentration, p53, p21, reactive oxygen species (ROS), and salivary levels of glutathione (GSH), heat shock proteins 27 and 70, and IgA between the ipsilateral and contralateral parotids. No difference was found for any of these parameters, even when grouping individuals by period of cell phone use in years or by monthly average calls in minutes. We provide molecular evidence that the exposure of parotid glands to cell phone use does not alter parotid salivary flow, protein concentration, or levels of proteins of genes that are directly or indirectly affected by heat-induced cellular stress. ©2014 American Association for Cancer Research.

  4. Multiple origins of spontaneously arising micronuclei in HeLa cells: Direct evidence from long-term live cell imaging

    International Nuclear Information System (INIS)

    Rao Xiaotang; Zhang Yingyin; Yi Qiyi; Hou Heli; Xu Bo; Chu Liang; Huang Yun; Zhang Wenrui; Fenech, Michael; Shi Qinghua

    2008-01-01

    Although micronuclei (MNi) are extensively used to evaluate genotoxic effects and chromosome instability, the most basic issue regarding their origins has not been completely addressed due to limitations of traditional methods. Recently, long-term live cell imaging was developed to monitor the dynamics of single cell in a real-time and high-throughput manner. In the present study, this state-of-the-art technique was employed to examine spontaneous micronucleus (MN) formation in untreated HeLa cells. We demonstrate that spontaneous MNi are derived from incorrectly aligned chromosomes in metaphase (displaced chromosomes, DCs), lagging chromosomes (LCs) and broken chromosome bridges (CBs) in later mitotic stages, but not nuclear buds in S phase. However, most of bipolar mitoses with DCs (91.29%), LCs (73.11%) and broken CBs (88.93%) did not give rise to MNi. Our data also show directly, for the first time, that MNi could originate spontaneously from (1) MNi already presented in the mother cells; (2) nuclear fragments that appeared during mitosis with CB; and (3) chromosomes being extruded into a minicell which fused with one of the daughter cells later. Quantitatively, most of MNi originated from LCs (63.66%), DCs (10.97%) and broken CBs (9.25%). Taken together, these direct evidences show that there are multiple origins for spontaneously arising MNi in HeLa cells and each mechanism contributes to overall MN formation to different extents

  5. Multiple origins of spontaneously arising micronuclei in HeLa cells: Direct evidence from long-term live cell imaging

    Energy Technology Data Exchange (ETDEWEB)

    Rao Xiaotang; Zhang Yingyin; Yi Qiyi; Hou Heli; Xu Bo; Chu Liang; Huang Yun; Zhang Wenrui [Laboratory of Molecular and Cell Genetics, Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 (China); Fenech, Michael [CSIRO Human Nutrition, PO Box 10041, Adelaide BC, Adelaide, SA 5000 (Australia); Shi Qinghua [Laboratory of Molecular and Cell Genetics, Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 (China)], E-mail: qshi@ustc.edu.cn

    2008-11-10

    Although micronuclei (MNi) are extensively used to evaluate genotoxic effects and chromosome instability, the most basic issue regarding their origins has not been completely addressed due to limitations of traditional methods. Recently, long-term live cell imaging was developed to monitor the dynamics of single cell in a real-time and high-throughput manner. In the present study, this state-of-the-art technique was employed to examine spontaneous micronucleus (MN) formation in untreated HeLa cells. We demonstrate that spontaneous MNi are derived from incorrectly aligned chromosomes in metaphase (displaced chromosomes, DCs), lagging chromosomes (LCs) and broken chromosome bridges (CBs) in later mitotic stages, but not nuclear buds in S phase. However, most of bipolar mitoses with DCs (91.29%), LCs (73.11%) and broken CBs (88.93%) did not give rise to MNi. Our data also show directly, for the first time, that MNi could originate spontaneously from (1) MNi already presented in the mother cells; (2) nuclear fragments that appeared during mitosis with CB; and (3) chromosomes being extruded into a minicell which fused with one of the daughter cells later. Quantitatively, most of MNi originated from LCs (63.66%), DCs (10.97%) and broken CBs (9.25%). Taken together, these direct evidences show that there are multiple origins for spontaneously arising MNi in HeLa cells and each mechanism contributes to overall MN formation to different extents.

  6. Inflammatory cell response to calcium phosphate biomaterial particles: an overview.

    Science.gov (United States)

    Velard, Frédéric; Braux, Julien; Amedee, Joëlle; Laquerriere, Patrice

    2013-02-01

    Bone is a metabolically active and highly organized tissue consisting of a mineral phase of hydroxyapatite (HA) and amorphous calcium phosphate (CaP) crystals deposited in an organic matrix. One objective of bone tissue engineering is to mimic the chemical and structural properties of this complex tissue. CaP ceramics, such as sintered HA and beta-tricalcium phosphate, are widely used as bone substitutes or prosthesis coatings because of their osteoconductive properties. These ceramic interactions with tissues induce a cell response that can be different according to the composition of the material. In this review, we discuss inflammatory cell responses to CaP materials to provide a comprehensive overview of mechanisms governing the integration or loosening of implants, which remains a major concern in tissue engineering. A focus on the effects of the functionalization of CaP biomaterials highlights potential ways to increase tissue integration and limit rejection processes. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  7. Cell wide responses to low oxygen exposure in Desulfovibriovulgaris Hildenborough

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, A.; Redding, A.; Joachimiak, M.; Arkin, A.; Borglin, S.; Dehal, P.; Chakraborty, R.; Geller, J.; Hazen, T.; He, Q.; Joyner, D.; Martin, V.; Wall, J.; Yang, Z.; Zhou, J.; Keasling, J.

    2007-03-11

    The responses of the anaerobic, sulfate-reducing Desulfovibrio vulgaris Hildenborough to low oxygen exposure (0.1% O{sub 2}) were monitored via transcriptomics and proteomics. Exposure to 0.1% O{sub 2} caused a decrease in growth rate without affecting viability. A concerted up regulation in the predicted peroxide stress response regulon (PerR) genes was observed in response to the 0.1% O{sub 2} exposure. Several of these candidates also showed increases in protein abundance. Among the remaining small number of transcript changes was the up regulation of the predicted transmembrane tetraheme cytochrome c3 complex. Other known oxidative stress response candidates remained unchanged during this low O{sub 2} exposure. To fully understand the results of the 0.1% O{sub 2} exposure, transcriptomics and proteomics data were collected for exposure to air using a similar experimental protocol. In contrast to the 0.1% O{sub 2} exposure, air exposure was detrimental to both the growth rate and viability and caused dramatic changes at both the transcriptome and proteome levels. Interestingly, the transcripts of the predicted PerR regulon genes were down regulated during air exposure. Our results highlight the differences in the cell wide response to low and high O{sub 2} levels of in D. vulgaris and suggest that while exposure to air is highly detrimental to D. vulgaris, this bacterium can successfully cope with periodic exposure to low O{sub 2} levels in its environment.

  8. Follicular helper T cells poise immune responses to the development of autoimmune pathology.

    Science.gov (United States)

    Gómez-Martín, Diana; Díaz-Zamudio, Mariana; Romo-Tena, Jorge; Ibarra-Sánchez, María J; Alcocer-Varela, Jorge

    2011-04-01

    Follicular helper T cells (T(FH)) have been implicated as a lineage that provides sufficient help to B cells in order to become professional antibody producers. This T helper subset is characterized by a distinctive cell-surface phenotype (CD4(+)CD57(+)CXCR5(+)) and cytokine profile (IL-21, IL-6, and IL-27) as well as transcriptional program (BCL-6, ICOS, and PD-1). Evidence supports the concept that T(FH) subset development, as well as for other lineages, is dependent on microenvironment cues that modulate a particular transcriptional program, susceptible to plasticity. Recently, it has been shown that BCL-6 and IL-21 act as master regulators for the development and function of T(FH) cells. Moreover, costimulation via ICOS, as well as signaling proteins such as SAP constitute required elements of the regulatory network that modulates T(FH) functions. T(FH) dysregulation has been implicated in the development of autoimmune pathology, such as SLE. Indeed, the Sanroque mice associated to the mutation of Roquin, a ubiquitin ligase, essential for the regulation of ICOS and germinal center responses, constitutes a model that shares features with human SLE. Recently, the expansion of "circulating T(FH) cells" (CD4(+)CXCR5(+)ICOS(high)PD1(high)) has been described for a subset of SLE patients that share T(FH) dependent features of disease with Sanroque mice, such as glomerulonephritis and cytopenias. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Reconstitution of the cellular response to DNA damage in vitro using damage-activated extracts from mammalian cells

    International Nuclear Information System (INIS)

    Roper, Katherine; Coverley, Dawn

    2012-01-01

    In proliferating mammalian cells, DNA damage is detected by sensors that elicit a cellular response which arrests the cell cycle and repairs the damage. As part of the DNA damage response, DNA replication is inhibited and, within seconds, histone H2AX is phosphorylated. Here we describe a cell-free system that reconstitutes the cellular response to DNA double strand breaks using damage-activated cell extracts and naïve nuclei. Using this system the effect of damage signalling on nuclei that do not contain DNA lesions can be studied, thereby uncoupling signalling and repair. Soluble extracts from G1/S phase cells that were treated with etoposide before isolation, or pre-incubated with nuclei from etoposide-treated cells during an in vitro activation reaction, restrain both initiation and elongation of DNA replication in naïve nuclei. At the same time, H2AX is phosphorylated in naïve nuclei in a manner that is dependent upon the phosphatidylinositol 3-kinase-like protein kinases. Notably, phosphorylated H2AX is not focal in naïve nuclei, but is evident throughout the nucleus suggesting that in the absence of DNA lesions the signal is not amplified such that discrete foci can be detected. This system offers a novel screening approach for inhibitors of DNA damage response kinases, which we demonstrate using the inhibitors wortmannin and LY294002. -- Highlights: ► A cell free system that reconstitutes the response to DNA damage in the absence of DNA lesions. ► Damage-activated extracts impose the cellular response to DNA damage on naïve nuclei. ► PIKK-dependent response impacts positively and negatively on two separate fluorescent outputs. ► Can be used to screen for inhibitors that impact on the response to damage but not on DNA repair. ► LY294002 and wortmannin demonstrate the system's potential as a pathway focused screening approach.

  10. Capacity of Lung Stroma to Educate Dendritic Cells Inhibiting Mycobacteria-Specific T-Cell Response Depends upon Genetic Susceptibility to Tuberculosis

    OpenAIRE

    Kapina, Marina A.; Rubakova, Elvira I.; Majorov, Konstantin B.; Logunova, Nadezhda N.; Apt, Alexander S.

    2013-01-01

    The balance between activation and inhibition of local immune responses in affected tissues during prolonged chronic infections is important for host protection. There is ample evidence that regulatory, tolerogenic dendritic cells (DC) are developed and present in tissues and inhibit overwhelming inflammatory reactions. Also, it was firmly established that stromal microenvironment of many organs is able to induce development of immature regulatory DC (DCreg), an essential element of a general...

  11. The ¿/d T-cell response to Plasmodium falciparum malaria in a population in which malaria is endemic

    DEFF Research Database (Denmark)

    Hviid, L; Kurtzhals, J A; Dodoo, D

    1996-01-01

    Frequencies and absolute numbers of peripheral gamma/delta T cells have been reported to increase after episodes of Plasmodium falciparum malaria in adults with limited or no previous malaria exposure. In contrast, little is known about the gamma/delta T-cell response to malaria in children from...... areas where malaria is endemic, who bear the burden of malaria-related morbidity and mortality. We investigated the gamma/delta T-cell response in 19 Ghanaian children from an area of hyperendemic, seasonal malaria transmission. The children presented with cerebral malaria (n = 7), severe malarial...... anemia (n = 5), or uncomplicated malaria (n = 7) and were monitored from admission until 4 weeks later. We found no evidence of increased frequencies of gamma/delta T cells in any of the patient groups, whereas one adult expatriate studied in Ghana and three adults admitted to the hospital in Copenhagen...

  12. Intraglomerular inhibition maintains mitral cell response contrast across input frequencies.

    Science.gov (United States)

    Shao, Zuoyi; Puche, Adam C; Shipley, Michael T

    2013-11-01

    Odor signals are transmitted to the olfactory bulb by olfactory nerve (ON) synapses onto mitral/tufted cells (MTCs) and external tufted cells (ETCs); ETCs provide additional feed-forward excitation to MTCs. Both are strongly regulated by intraglomerular inhibition that can last up to 1 s and, when blocked, dramatically increases ON-evoked MC spiking. Intraglomerular inhibition thus limits the magnitude and duration of MC spike responses to sensory input. In vivo, sensory input is repetitive, dictated by sniffing rates from 1 to 8 Hz, potentially summing intraglomerular inhibition. To investigate this, we recorded MTC responses to 1- to 8-Hz ON stimulation in slices. Inhibitory postsynaptic current area (charge) following each ON stimulation was unchanged from 1 to 5 Hz and modestly paired-pulse attenuated at 8 Hz, suggesting there is no summation and only limited decrement at the highest input frequencies. Next, we investigated frequency independence of intraglomerular inhibition on MC spiking. MCs respond to single ON shocks with an initial spike burst followed by reduced spiking decaying to baseline. Upon repetitive ON stimulation peak spiking is identical across input frequencies but the ratio of peak-to-minimum rate before the stimulus (max-min) diminishes from 30:1 at 1 Hz to 15:1 at 8 Hz. When intraglomerular inhibition is selectively blocked, peak spike rate is unchanged but trough spiking increases markedly decreasing max-min firing ratios from 30:1 at 1 Hz to 2:1 at 8 Hz. Together, these results suggest intraglomerular inhibition is relatively frequency independent and can "sharpen" MC responses to input across the range of frequencies. This suggests that glomerular circuits can maintain "contrast" in MC encoding during sniff-sampled inputs.

  13. Injectable, Biomolecule-Responsive Polypeptide Hydrogels for Cell Encapsulation and Facile Cell Recovery through Triggered Degradation.

    Science.gov (United States)

    Xu, Qinghua; He, Chaoliang; Zhang, Zhen; Ren, Kaixuan; Chen, Xuesi

    2016-11-16

    Injectable hydrogels have been widely investigated in biomedical applications, and increasing demand has been proposed to achieve dynamic regulation of physiological properties of hydrogels. Herein, a new type of injectable and biomolecule-responsive hydrogel based on poly(l-glutamic acid) (PLG) grafted with disulfide bond-modified phloretic acid (denoted as PLG-g-CPA) was developed. The hydrogels formed in situ via enzymatic cross-linking under physiological conditions in the presence of horseradish peroxidase and hydrogen peroxide. The physiochemical properties of the hydrogels, including gelation time and the rheological property, were measured. Particularly, the triggered degradation of the hydrogel in response to a reductive biomolecule, glutathione (GSH), was investigated in detail. The mechanical strength and inner porous structure of the hydrogel were influenced by the addition of GSH. The polypeptide hydrogel was used as a three-dimensional (3D) platform for cell encapsulation, which could release the cells through triggered disruption of the hydrogel in response to the addition of GSH. The cells released from the hydrogel were found to maintain high viability. Moreover, after subcutaneous injection into rats, the PLG-g-CPA hydrogels with disulfide-containing cross-links exhibited a markedly faster degradation behavior in vivo compared to that of the PLG hydrogels without disulfide cross-links, implying an interesting accelerated degradation process of the disulfide-containing polypeptide hydrogels in the physiological environment in vivo. Overall, the injectable and biomolecule-responsive polypeptide hydrogels may serve as a potential platform for 3D cell culture and easy cell collection.

  14. fMRI Evidence of ‘Mirror’ Responses to Geometric Shapes

    Science.gov (United States)

    Press, Clare; Catmur, Caroline; Cook, Richard; Widmann, Hannah; Heyes, Cecilia; Bird, Geoffrey

    2012-01-01

    Mirror neurons may be a genetic adaptation for social interaction [1]. Alternatively, the associative hypothesis [2], [3] proposes that the development of mirror neurons is driven by sensorimotor learning, and that, given suitable experience, mirror neurons will respond to any stimulus. This hypothesis was tested using fMRI adaptation to index populations of cells with mirror properties. After sensorimotor training, where geometric shapes were paired with hand actions, BOLD response was measured while human participants experienced runs of events in which shape observation alternated with action execution or observation. Adaptation from shapes to action execution, and critically, observation, occurred in ventral premotor cortex (PMv) and inferior parietal lobule (IPL). Adaptation from shapes to execution indicates that neuronal populations responding to the shapes had motor properties, while adaptation to observation demonstrates that these populations had mirror properties. These results indicate that sensorimotor training induced populations of cells with mirror properties in PMv and IPL to respond to the observation of arbitrary shapes. They suggest that the mirror system has not been shaped by evolution to respond in a mirror fashion to biological actions; instead, its development is mediated by stimulus-general processes of learning within a system adapted for visuomotor control. PMID:23251653

  15. Dendritic cells fused with different pancreatic carcinoma cells induce different T-cell responses

    Directory of Open Access Journals (Sweden)

    Andoh Y

    2013-01-01

    Full Text Available Yoshiaki Andoh,1,2 Naohiko Makino,2 Mitsunori Yamakawa11Department of Pathological Diagnostics, 2Department of Gastroenterology, Yamagata University School of Medicine, Yamagata, JapanBackground: It is unclear whether there are any differences in the induction of cytotoxic T lymphocytes (CTL and CD4+CD25high regulatory T-cells (Tregs among dendritic cells (DCs fused with different pancreatic carcinomas. The aim of this study was to compare the ability to induce cytotoxicity by human DCs fused with different human pancreatic carcinoma cell lines and to elucidate the causes of variable cytotoxicity among cell lines.Methods: Monocyte-derived DCs, which were generated from peripheral blood mononuclear cells (PBMCs, were fused with carcinoma cells such as Panc-1, KP-1NL, QGP-1, and KP-3L. The induction of CTL and Tregs, and cytokine profile of PBMCs stimulated by fused DCs were evaluated.Results: The cytotoxicity against tumor targets induced by PBMCs cocultured with DCs fused with QGP-1 (DC/QGP-1 was very low, even though PBMCs cocultured with DCs fused with other cell lines induced significant cytotoxicity against the respective tumor target. The factors causing this low cytotoxicity were subsequently investigated. DC/QGP-1 induced a significant expansion of Tregs in cocultured PBMCs compared with DC/KP-3L. The level of interleukin-10 secreted in the supernatants of PBMCs cocultured with DC/QGP-1 was increased significantly compared with that in DC/KP-3L. Downregulation of major histocompatibility complex class I expression and increased secretion of vascular endothelial growth factor were observed with QGP-1, as well as in the other cell lines.Conclusion: The present study demonstrated that the cytotoxicity induced by DCs fused with pancreatic cancer cell lines was different between each cell line, and that the reduced cytotoxicity of DC/QGP-1 might be related to the increased secretion of interleukin-10 and the extensive induction of Tregs

  16. Radiogenic responses of normal cells induced by fractionated irradiation -a simulation study. Pt. 2. Late responses

    International Nuclear Information System (INIS)

    Duechting, W.; Ulmer, W.; Ginsberg, T.; Kikhounga-N'Got, O.; Saile, C.

    1995-01-01

    Based on controlled theory, a computed simulation model has been constructed which describes the time course of slowly responding normal cells after irradiation exposure. Subsequently, different clinical irradiation schemes are compared in regard to their delayed radiogenic responses referred to as late effects in radiological terminology. A cybernetic model of a paraenchymal tissue consisting of dominantly resting functional cells has been developed and transferred into a computer model. The radiation effects are considered by characteristic cell parameters as well as by the linear-quadratic model. Three kinds of tissue (brain and lung parenchym of the mouse, liver parenchym of rat) have been irradiated in the model according to standard-, super-, hyperfractionation and a single high dose per week. The simulation studies indicate that the late reaction of brain parenchym to hyperfractionation (3 x 1.5 Gy per day) and of lung parenchym tissue with regard to all fractionation schemes applied is particularly severe. The behavior of liver parenchym is not unique. A comparison of the simulation results basing to the survival of cell numbers with clinical experience and practice shows that the clinical reality can qualitatively be represented by the model. This opens the door for connecting side effects to normal tissue with the corresponding tumor efficacy (discussed in previous papers). The model is open to further refinement and to discussions referring to the phenomenon of late effects. (orig.) [de

  17. Striatal response to reward anticipation: evidence for a systems-level intermediate phenotype for schizophrenia.

    Science.gov (United States)

    Grimm, Oliver; Heinz, Andreas; Walter, Henrik; Kirsch, Peter; Erk, Susanne; Haddad, Leila; Plichta, Michael M; Romanczuk-Seiferth, Nina; Pöhland, Lydia; Mohnke, Sebastian; Mühleisen, Thomas W; Mattheisen, Manuel; Witt, Stephanie H; Schäfer, Axel; Cichon, Sven; Nöthen, Markus; Rietschel, Marcella; Tost, Heike; Meyer-Lindenberg, Andreas

    2014-05-01

    the NRG1 genotype (higher striatal responses in controls with the protective rs10503929 C allele; familywise error-corrected P reward anticipation in a directionality and localization consistent with prior patient findings. This provides evidence for a functional neural system mechanism related to familial risk. The phenotype can be assessed reliably, is independent of alterations in striatal structure, and is influenced by a schizophrenia candidate gene variant in NRG1. These data encourage us to further investigate the genetic and molecular contributions to this phenotype.

  18. Conventional CD4+ T cells present bacterial antigens to induce cytotoxic and memory CD8+ T cell responses.

    Science.gov (United States)

    Cruz-Adalia, Aránzazu; Ramirez-Santiago, Guillermo; Osuna-Pérez, Jesús; Torres-Torresano, Mónica; Zorita, Virgina; Martínez-Riaño, Ana; Boccasavia, Viola; Borroto, Aldo; Martínez Del Hoyo, Gloria; González-Granado, José María; Alarcón, Balbino; Sánchez-Madrid, Francisco; Veiga, Esteban

    2017-11-17

    Bacterial phagocytosis and antigen cross-presentation to activate CD8 + T cells are principal functions of professional antigen presenting cells. However, conventional CD4 + T cells also capture and kill bacteria from infected dendritic cells in a process termed transphagocytosis (also known as transinfection). Here, we show that transphagocytic T cells present bacterial antigens to naive CD8 + T cells, which proliferate and become cytotoxic in response. CD4 + T-cell-mediated antigen presentation also occurs in vivo in the course of infection, and induces the generation of central memory CD8 + T cells with low PD-1 expression. Moreover, transphagocytic CD4 + T cells induce protective anti-tumour immune responses by priming CD8 + T cells, highlighting the potential of CD4 + T cells as a tool for cancer immunotherapy.

  19. Evidence review of hydroxyurea for the prevention of sickle cell complications in low-income countries.

    Science.gov (United States)

    Mulaku, Mercy; Opiyo, Newton; Karumbi, Jamlick; Kitonyi, Grace; Thoithi, Grace; English, Mike

    2013-11-01

    Hydroxyurea is widely used in high-income countries for the management of sickle cell disease (SCD) in children. In Kenyan clinical guidelines, hydroxyurea is only recommended for adults with SCD. Yet many deaths from SCD occur in early childhood, deaths that might be prevented by an effective, disease modifying intervention. The aim of this review was to summarise the available evidence on the efficacy, effectiveness and safety of hydroxyurea in the management of SCD in children below 5 years of age to support guideline development in Kenya. We undertook a systematic review and used the Grading of Recommendations Assessment, Development and Evaluation system to appraise the quality of identified evidence. Overall, available evidence from 1 systematic review (n=26 studies), 2 randomised controlled trials (n=354 children), 14 observational studies and 2 National Institute of Health reports suggest that hydroxyurea may be associated with improved fetal haemoglobin levels, reduced rates of hospitalisation, reduced episodes of acute chest syndrome and decreased frequency of pain events in children with SCD. However, it is associated with adverse events (eg, neutropenia) when high to maximum tolerated doses are used. Evidence is lacking on whether hydroxyurea improves survival if given to young children. Majority of the included studies were of low quality and mainly from high-income countries. Overall, available limited evidence suggests that hydroxyurea may improve morbidity and haematological outcomes in SCD in children aged below 5 years and appears safe in settings able to provide consistent haematological monitoring.

  20. Uterine epithelial cell proliferation and endometrial hyperplasia: evidence from a mouse model.

    Science.gov (United States)

    Gao, Yang; Li, Shu; Li, Qinglei

    2014-08-01

    In the uterus, epithelial cell proliferation changes during the estrous cycle and pregnancy. Uncontrolled epithelial cell proliferation results in implantation failure and/or cancer development. Transforming growth factor-β (TGF-β) signaling is a fundamental regulator of diverse biological processes and is indispensable for multiple reproductive functions. However, the in vivo role of TGF-β signaling in uterine epithelial cells remains poorly defined. We have shown that in the uterus, conditional deletion of the Type 1 receptor for TGF-β (Tgfbr1) using anti-Müllerian hormone receptor type 2 (Amhr2) Cre leads to myometrial defects. Here, we describe enhanced epithelial cell proliferation by immunostaining of Ki67 in the uteri of these mice. The aberration culminated in endometrial hyperplasia in aged females. To exclude the potential influence of ovarian steroid hormones, the proliferative status of uterine epithelial cells was assessed following ovariectomy. Increased uterine epithelial cell proliferation was also revealed in ovariectomized Tgfbr1 Amhr2-Cre conditional knockout mice. We further demonstrated that transcript levels for fibroblast growth factor 10 (Fgf10) were markedly up-regulated in Tgfbr1 Amhr2-Cre conditional knockout uteri. Consistently, treatment of primary uterine stromal cells with TGF-β1 significantly reduced Fgf10 mRNA expression. Thus, our findings suggest a potential involvement of TGFBR1-mediated signaling in the regulation of uterine epithelial cell proliferation, and provide genetic evidence supporting the role of uterine epithelial cell proliferation in the pathogenesis of endometrial hyperplasia. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. RNA disruption is associated with response to multiple classes of chemotherapy drugs in tumor cell lines

    International Nuclear Information System (INIS)

    Narendrula, Rashmi; Mispel-Beyer, Kyle; Guo, Baoqing; Parissenti, Amadeo M.; Pritzker, Laura B.; Pritzker, Ken; Masilamani, Twinkle; Wang, Xiaohui; Lannér, Carita

    2016-01-01

    Cellular stressors and apoptosis-inducing agents have been shown to induce ribosomal RNA (rRNA) degradation in eukaryotic cells. Recently, RNA degradation in vivo was observed in patients with locally advanced breast cancer, where mid-treatment tumor RNA degradation was associated with complete tumor destruction and enhanced patient survival. However, it is not clear how widespread chemotherapy induced “RNA disruption” is, the extent to which it is associated with drug response or what the underlying mechanisms are. Ovarian (A2780, CaOV3) and breast (MDA-MB-231, MCF-7, BT474, SKBR3) cancer cell lines were treated with several cytotoxic chemotherapy drugs and total RNA was isolated. RNA was also prepared from docetaxel resistant A2780DXL and carboplatin resistant A2780CBN cells following drug exposure. Disruption of RNA was analyzed by capillary electrophoresis. Northern blotting was performed using probes complementary to the 28S and 18S rRNA to determine the origins of degradation bands. Apoptosis activation was assessed by flow cytometric monitoring of annexin-V and propidium iodide (PI) binding to cells and by measuring caspase-3 activation. The link between apoptosis and RNA degradation (disruption) was investigated using a caspase-3 inhibitor. All chemotherapy drugs tested were capable of inducing similar RNA disruption patterns. Docetaxel treatment of the resistant A2780DXL cells and carboplatin treatment of the A2780CBN cells did not result in RNA disruption. Northern blotting indicated that two RNA disruption bands were derived from the 3’-end of the 28S rRNA. Annexin-V and PI staining of docetaxel treated cells, along with assessment of caspase-3 activation, showed concurrent initiation of apoptosis and RNA disruption, while inhibition of caspase-3 activity significantly reduced RNA disruption. Supporting the in vivo evidence, our results demonstrate that RNA disruption is induced by multiple chemotherapy agents in cell lines from different tissues

  2. RNA disruption is associated with response to multiple classes of chemotherapy drugs in tumor cell lines.

    Science.gov (United States)

    Narendrula, Rashmi; Mispel-Beyer, Kyle; Guo, Baoqing; Parissenti, Amadeo M; Pritzker, Laura B; Pritzker, Ken; Masilamani, Twinkle; Wang, Xiaohui; Lannér, Carita

    2016-02-24

    Cellular stressors and apoptosis-inducing agents have been shown to induce ribosomal RNA (rRNA) degradation in eukaryotic cells. Recently, RNA degradation in vivo was observed in patients with locally advanced breast cancer, where mid-treatment tumor RNA degradation was associated with complete tumor destruction and enhanced patient survival. However, it is not clear how widespread chemotherapy induced "RNA disruption" is, the extent to which it is associated with drug response or what the underlying mechanisms are. Ovarian (A2780, CaOV3) and breast (MDA-MB-231, MCF-7, BT474, SKBR3) cancer cell lines were treated with several cytotoxic chemotherapy drugs and total RNA was isolated. RNA was also prepared from docetaxel resistant A2780DXL and carboplatin resistant A2780CBN cells following drug exposure. Disruption of RNA was analyzed by capillary electrophoresis. Northern blotting was performed using probes complementary to the 28S and 18S rRNA to determine the origins of degradation bands. Apoptosis activation was assessed by flow cytometric monitoring of annexin-V and propidium iodide (PI) binding to cells and by measuring caspase-3 activation. The link between apoptosis and RNA degradation (disruption) was investigated using a caspase-3 inhibitor. All chemotherapy drugs tested were capable of inducing similar RNA disruption patterns. Docetaxel treatment of the resistant A2780DXL cells and carboplatin treatment of the A2780CBN cells did not result in RNA disruption. Northern blotting indicated that two RNA disruption bands were derived from the 3'-end of the 28S rRNA. Annexin-V and PI staining of docetaxel treated cells, along with assessment of caspase-3 activation, showed concurrent initiation of apoptosis and RNA disruption, while inhibition of caspase-3 activity significantly reduced RNA disruption. Supporting the in vivo evidence, our results demonstrate that RNA disruption is induced by multiple chemotherapy agents in cell lines from different tissues and is

  3. The effect of demand response on purchase intention of distributed generation: Evidence from Japan

    International Nuclear Information System (INIS)

    Nakada, Tatsuhiro; Shin, Kongjoo; Managi, Shunsuke

    2016-01-01

    Participation in demand response (DR) may affect a consumer's electric consumption pattern through consumption load curtailment, a shift in the consumption timing or increasing the utilization of distributed generation (DG). This paper attempts to provide empirical evidence of DR's effect on DG adoption by household consumers. By using the original Internet survey data of 5442 household respondents in Japan conducted in January 2015, we focus on the effect of the time-of-use (TOU) tariff on the purchasing intention of photovoltaic systems (PV). The empirical results show the following: 1) current TOU plan users have stronger PV purchase intentions than the other plan users, 2) respondents who are familiar with the DR program have relatively higher purchase intentions compared with their counterparts, and 3) when the respondents are requested to assume participation in the virtual TOU plan designed for the survey, which resembles plans currently available through major companies, 1.2% of the households have decided to purchase PV. In addition, we provide calculations of TOU's impacts on the official PV adoption and emissions reduction targets, and discuss policy recommendations to increase recognitions and participations in TOU programs. - Highlights: •Studies the effect of demand response on purchase intention of PV. •Uses originally collected Internet Japanese household survey data in 2015. •Finds that time-of-use (TOU) plan has positive effect on PV purchase intentions. •Calculates latent TOU impacts on PV installations and emissions reduction targets. •Discusses policy recommendations to increase participations in TOU programs.

  4. Equine colostral carbohydrates reduce lipopolysaccharide-induced inflammatory responses in equine peripheral blood mononuclear cells.

    Science.gov (United States)

    Vendrig, J C; Coffeng, L E; Fink-Gremmels, J

    2012-12-01

    Increasing evidence suggests that reactions to lipopolysaccharide (LPS), particularly in the gut, can be partly or completely mitigated by colostrum- and milk-derived oligosaccharides. Confirmation of this hypothesis could lead to the development of new therapeutic concepts. To demonstrate the influence of equine colostral carbohydrates on the inflammatory response in an in vitro model with equine peripheral blood mononuclear cells (PBMCs). Carbohydrates were extracted from mare colostrum, and then evaluated for their influence on LPS-induced inflammatory responses in PBMCs isolated from the same mares, mRNA expression of tumour necrosis factor-alpha, interleukin-6 and interleukin-10 was measured as well as the protein levels of tumour necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10). Equine colostral carbohydrates significantly reduced LPS-induced TNF-alpha protein at both times measured and significantly reduced LPS-induced TNF-alpha, IL-6 and IL-10 mRNA expression by PBMCs. Moreover, cell viability significantly increased in the presence of high concentrations of colostral carbohydrates. Carbohydrates derived from equine colostrum reduce LPS-induced inflammatory responses of equine PBMCs. Colostrum and milk-derived carbohydrates are promising candidates for new concepts in preventive and regenerative medicine.

  5. Ability of γδ T cells to modulate the Foxp3 T cell response is dependent on adenosine.

    Directory of Open Access Journals (Sweden)

    Dongchun Liang

    Full Text Available Whether γδ T cells inhibit or enhance the Foxp3 T cell response depends upon their activation status. The critical enhancing effector in the supernatant is adenosine. Activated γδ T cells express adenosine receptors at high levels, which enables them to deprive Foxp3+ T cells of adenosine, and to inhibit their expansion. Meanwhile, cell-free supernatants of γδ T cell cultures enhance Foxp3 T cell expansion. Thus, inhibition and enhancement by γδ T cells of Foxp3 T cell response are a reflection of the balance between adenosine production and absorption by γδ T cells. Non-activated γδ T cells produce adenosine but bind little, and thus enhance the Foxp3 T cell response. Activated γδ T cells express high density of adenosine receptors and have a greatly increased ability to bind adenosine. Extracellular adenosine metabolism and expression of adenosine receptor A2ARs by γδ T cells played a major role in the outcome of γδ and Foxp3 T cell interactions. A better understanding of the functional conversion of γδ T cells could lead to γδ T cell-targeted immunotherapies for related diseases.

  6. Anti-Donor Immune Responses Elicited by Allogeneic Mesenchymal Stem Cells and Their Extracellular Vesicles: Are We Still Learning?

    Directory of Open Access Journals (Sweden)

    Paul Lohan

    2017-11-01

    Full Text Available Mesenchymal stromal cells (MSC have been used to treat a broad range of disease indications such as acute and chronic inflammatory disorders, autoimmune diseases, and transplant rejection due to their potent immunosuppressive/anti-inflammatory properties. The breadth of their usage is due in no small part to the vast quantity of published studies showing their ability to modulate multiple immune cell types of both the innate and adaptive immune response. While patient-derived (autologous MSC may be the safer choice in terms of avoiding unwanted immune responses, factors including donor comorbidities may preclude these cells from use. In these situations, allogeneic MSC derived from genetically unrelated individuals must be used. While allogeneic MSC were initially believed to be immune-privileged, substantial evidence now exists to prove otherwise with multiple studies documenting specific cellular and humoral immune responses against donor antigens following administration of these cells. In this article, we will review recent published studies using non-manipulated, inflammatory molecule-activated (licensed and differentiated allogeneic MSC, as well as MSC extracellular vesicles focusing on the immune responses to these cells and whether or not such responses have an impact on allogeneic MSC-mediated safety and efficacy.

  7. Rapid response learning of brand logo priming: Evidence that brand priming is not dominated by rapid response learning.

    Science.gov (United States)

    Boehm, Stephan G; Smith, Ciaran; Muench, Niklas; Noble, Kirsty; Atherton, Catherine

    2017-08-31

    Repetition priming increases the accuracy and speed of responses to repeatedly processed stimuli. Repetition priming can result from two complementary sources: rapid response learning and facilitation within perceptual and conceptual networks. In conceptual classification tasks, rapid response learning dominates priming of object recognition, but it does not dominate priming of person recognition. This suggests that the relative engagement of network facilitation and rapid response learning depends on the stimulus domain. Here, we addressed the importance of the stimulus domain for rapid response learning by investigating priming in another domain, brands. In three experiments, participants performed conceptual decisions for brand logos. Strong priming was present, but it was not dominated by rapid response learning. These findings add further support to the importance of the stimulus domain for the relative importance of network facilitation and rapid response learning, and they indicate that brand priming is more similar to person recognition priming than object recognition priming, perhaps because priming of both brands and persons requires individuation.

  8. [Conjunctival squamous cell carcinoma: paradoxical response to interferon eyedrops].

    Science.gov (United States)

    Mata, E; Conesa, E; Castro, M; Martínez, L; de Pablo, C; González, M L

    2014-07-01

    A 67 year-old male seen for a longstanding corneal-conjunctival tumor. topical interferon α2b (IFN-α2b) 10 U/ml. A significant increase in lesion size was observed after 8 weeks. A surgical excision with cryotherapy was then performed. Pathological examination confirmed the diagnosis of squamous cell carcinoma. At this time the patient was found to have a positive HIV serology. Conjunctival intraepithelial neoplasia (CIN) is a pre-cancerous lesion of the ocular surface. Medical treatment of CIN is essentially with IFN-α2b due to its antiviral/antitumor properties. In patients with HIV, treatment response could be paradoxical. We recommend serology for HIV before treatment with topical IFN-α2b. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  9. Evidence against suppressor cell involvement in naturally acquired tolerance of a minor histocompatibility antigen

    International Nuclear Information System (INIS)

    Johnson, L.L.

    1991-01-01

    The hypothesis was investigated that suppressor cells may be responsible for maintenance of immunologic tolerance of a minor H3 antigen in mice that express the antigen naturally. Lymphoid cell populations from B6.C-H-24c (HW54) mice, a congenic-resistant strain histoincompatible with H-24b-expressing C57BL/6 (B6) mice only with respect to the H-24 locus, were examined in cell-transfer experiments to see if they contained naturally arising H-24c-specific suppressor cells. The H-24 antigen was chosen for these studies because, unlike most other minor and major histocompatibility (H) antigens, it is not detectable on mature lymphoid cells by any of several functional criteria. Thus transfer of HW54 lymphoid cells to B6 hosts could be done without the complication of inducing hyporesponsiveness de novo in the host, as occurs with other minor H antigens that are expressed on lymphocytes. B6 hosts were given HW54 skin grafts along with HW54 lymphoid cells to assess their tolerance of the H-24c-encoded antigen. The hosts were either (1) normal, nonimmune B6 mice; (2) B6 mice rendered immunodeficient by thymectomy and irradiation (TxB) and repopulated with H-24c-immune B6 lymphocytes; or (3) TxB B6 hosts repopulated with nonimmune B6 lymphocytes. In each case it was found that the additionally infused HW54 lymphoid cells did not suppress the ability of these hosts to reject HW54 skin grafts. In other words, HW54 lymphoid cells appear not to possess suppressive activity specific for the H-24c antigen that might maintain antigen-specific natural tolerance. Additional experiments were performed to determine whether HW54 lymphoid cells can inhibit the ability of sublethally irradiated B6 mice to regain the capacity to reject HW54 skin

  10. Evidence that transferrin supports cell proliferation by supplying iron for DNA synthesis

    International Nuclear Information System (INIS)

    Laskey, J.; Webb, I.; Schulman, H.M.; Ponka, P.

    1988-01-01

    Transferrin is essential for cell proliferation and it was suggested that it may trigger a proliferative response following its interaction with receptors, serving as a growth factor. However, since the only clearly defined function of transferrin is iron transport, it may merely serve as an iron donor. To further clarify this issue, the authors took advantage of an iron chelate, ferric salicylaldehyde isonicotinoyl hydrazone (Fe-SIH), which they developed and previously demonstrated to efficiently supply iron to cells without using physiological transferrin receptor pathway. As expected, they observed that blocking monoclonal antibodies against transferrin receptors inhibited proliferation of both Raji and murine erythroleukemia cells. This inhibited cell growth was rescued upon the addition of Fe-SIH which was also shown to deliver iron to Raji cells in the presence of blocking anti-transferrin receptor antibodies. Moreover, blocking anti-transferrin receptor antibodies inhibited [ 3 H]thymidine incorporation into DNA and this inhibition could be overcome by added Fe-SIH. In addition, Fe-SIH slightly stimulated, while SIH (an iron chelator) significantly inhibited, DNA synthesis in phytohemagglutinin-stimulated peripheral blood lymphocytes. Taken together, these results indicate that the only function of transferrin supporting cell proliferation is to supply cells with iron

  11. Cell type-specific responses to salinity - the epidermal bladder cell transcriptome of Mesembryanthemum crystallinum.

    Science.gov (United States)

    Oh, Dong-Ha; Barkla, Bronwyn J; Vera-Estrella, Rosario; Pantoja, Omar; Lee, Sang-Yeol; Bohnert, Hans J; Dassanayake, Maheshi

    2015-08-01

    Mesembryanthemum crystallinum (ice plant) exhibits extreme tolerance to salt. Epidermal bladder cells (EBCs), developing on the surface of aerial tissues and specialized in sodium sequestration and other protective functions, are critical for the plant's stress adaptation. We present the first transcriptome analysis of EBCs isolated from intact plants, to investigate cell type-specific responses during plant salt adaptation. We developed a de novo assembled, nonredundant EBC reference transcriptome. Using RNAseq, we compared the expression patterns of the EBC-specific transcriptome between control and salt-treated plants. The EBC reference transcriptome consists of 37 341 transcript-contigs, of which 7% showed significantly different expression between salt-treated and control samples. We identified significant changes in ion transport, metabolism related to energy generation and osmolyte accumulation, stress signalling, and organelle functions, as well as a number of lineage-specific genes of unknown function, in response to salt treatment. The salinity-induced EBC transcriptome includes active transcript clusters, refuting the view of EBCs as passive storage compartments in the whole-plant stress response. EBC transcriptomes, differing from those of whole plants or leaf tissue, exemplify the importance of cell type-specific resolution in understanding stress adaptive mechanisms. No claim to original US government works. New Phytologist © 2015 New Phytologist Trust.

  12. Cell-based Therapy for Acute Organ Injury: Preclinical Evidence and On-going Clinical Trials Using Mesenchymal Stem Cells

    Science.gov (United States)

    Monsel, Antoine; Zhu, Ying-gang; Gennai, Stephane; Hao, Qi; Liu, Jia; Lee, Jae W.

    2014-01-01

    Critically ill patients often suffer from multiple organ failures involving lung, kidney, liver or brain. Genomic, proteomic and metabolomic approaches highlight common injury mechanisms leading to acute organ failure. This underlines the need to focus on therapeutic strategies affecting multiple injury pathways. The use of adult stem cells such as mesenchymal stem or stromal cells (MSC) may represent a promising new therapeutic approach as increasing evidence shows that MSC can exert protective effects following injury through the release of pro-mitotic, anti-apoptotic, anti-inflammatory and immunomodulatory soluble factors. Furthermore, they can mitigate metabolomic and oxidative stress imbalance. In this work, we review the biological capabilities of MSC and the results of clinical trials using MSC as therapy in acute organ injuries. Although preliminary results are encouraging, more studies concerning safety and efficacy of MSC therapy are needed to determine their optimal clinical use. PMID:25211170

  13. Helicobacter pylori impairs murine dendritic cell responses to infection.

    Directory of Open Access Journals (Sweden)

    Ya-Hui Wang

    Full Text Available BACKGROUND: Helicobacter pylori, a human pathogen associated with chronic gastritis, peptic ulcer and gastric malignancies, is generally viewed as an extracellular microorganism. Here, we show that H. pylori replicates in murine bone marrow derived-dendritic cells (BMDCs within autophagosomes. METHODOLOGY/PRINCIPAL FINDINGS: A 10-fold increase of CFU is found between 2 h and 6 h p.i. in H. pylori-infected BMDCs. Autophagy is induced around the bacterium and participates at late time points of infection for the clearance of intracellular H. pylori. As a consequence of infection, LC3, LAMP1 and MHC class II molecules are retained within the H. pylori-containing vacuoles and export of MHC class II molecules to cell surface is blocked. However, formalin-fixed H. pylori still maintain this inhibitory activity in BMDC derived from wild type mice, but not in from either TLR4 or TLR2-deficient mice, suggesting the involvement of H. pylori-LPS in this process. TNF-alpha, IL-6 and IL-10 expression was also modulated upon infection showing a TLR2-specific dependent IL-10 secretion. No IL-12 was detected favoring the hypothesis of a down modulation of DC functions during H. pylori infection. Furthermore, antigen-specific T cells proliferation was also impaired upon infection. CONCLUSIONS/SIGNIFICANCE: H. pylori can infect and replicate in BMDCs and thereby affects DC-mediated immune responses. The implication of this new finding is discussed for the biological life cycle of H. pylori in the host.

  14. Chronic lymphocytic leukemia cells acquire regulatory B-cell properties in response to TLR9 and CD40 activation.

    Science.gov (United States)

    Ringelstein-Harlev, Shimrit; Avivi, Irit; Fanadka, Mona; Horowitz, Netanel A; Katz, Tami

    2018-02-15

    Circulating chronic lymphocytic leukemia (CLL) cells share phenotypic features with certain subsets of regulatory B-cells (Bregs). The latter cells have been reported to negatively regulate immune cell responses, mostly by provision of IL-10. The purpose of the current study was to identify and delineate Breg properties of CLL cells. B-cells and T-cells were obtained from the peripheral blood of untreated CLL patients diagnosed according to the 2008 Guidelines of the International Workshop on Chronic Lymphocytic Leukemia. Co-culture assays were used to examine the ability of CLL cells to suppress autologous T-cell immune responses. IL-10 potency of CLL cells was assessed following stimulation with activators of the toll-like receptor 9 (TLR9) or CD40 and was correlated with the inhibitory activity of the cells. TLR9-activated CLL cells were found to increase the frequency of CD4 + CD25 hi FOXp3 + regulatory T-cells (Tregs) and to inhibit autologous CD4 + T-cell proliferation. This signaling cascade proved to control IL-10 generation in CLL cells, which in turn promoted the inhibition of T-cell proliferation by CLL cells. However, CD40 activation of CLL cells, while exhibiting a similar ability to augment Treg frequency, did not either affect IL-10 generation or T-cell proliferation. In conclusion, CLL cells demonstrate a unique clonal quality of adopting Breg properties which promote modulation of T-cell characteristics. TLR9 appears to be a potent activator of regulatory abilities in CLL cells, possibly contributing to preferential immune escape of TLR9-responsive cells.

  15. To investigate the necessity of STRA6 upregulation in T cells during T cell immune responses.

    Directory of Open Access Journals (Sweden)

    Rafik Terra

    Full Text Available Our earlier study revealed that STRA6 (stimulated by retinoic acid gene 6 was up-regulated within 3 h of TCR stimulation. STRA6 is the high-affinity receptor for plasma retinol-binding protein (RBP and mediates cellular vitamin A uptake. We generated STRA6 knockout (KO mice to assess whether such up-regulation was critical for T-cell activation, differentiation and function. STRA6 KO mice under vitamin A sufficient conditions were fertile without apparent anomalies upon visual inspection. The size, cellularity and lymphocyte subpopulations of STRA6 KO thymus and spleen were comparable to those of their wild type (WT controls. KO and WT T cells were similar in terms of TCR-stimulated proliferation in vitro and homeostatic expansion in vivo. Naive KO CD4 cells differentiated in vitro into Th1, Th2, Th17 as well as regulatory T cells in an analogous manner as their WT counterparts. In vivo experiments revealed that anti-viral immune responses to lymphocytic choriomeningitis virus in KO mice were comparable to those of WT controls. We also demonstrated that STRA6 KO and WT mice had similar glucose tolerance. Total vitamin A levels are dramatically lower in the eyes of KO mice as compared to those of WT mice, but the levels in other organs were not significantly affected after STRA6 deletion under vitamin A sufficient conditions, indicating that the eye is the mouse organ most sensitive to the loss of STRA6. Our results demonstrate that 1 in vitamin A sufficiency, the deletion of STRA6 in T cells does no affect the T-cell immune responses so-far tested, including those depend on STAT5 signaling; 2 STRA6-independent vitamin A uptake compensated the lack of STRA6 in lymphoid organs under vitamin A sufficient conditions in mice; 3 STRA6 is critical for vitamin A uptake in the eyes even in vitamin A sufficiency.

  16. NLRP10 Enhances CD4+ T-Cell-Mediated IFNγ Response via Regulation of Dendritic Cell-Derived IL-12 Release

    Directory of Open Access Journals (Sweden)

    Maurizio Vacca

    2017-11-01

    Full Text Available NLRP10 is a nucleotide-binding oligomerization domain-like receptor that functions as an intracellular pattern recognition receptor for microbial products. Here, we generated a Nlrp10−/− mouse to delineate the role of NLRP10 in the host immune response and found that Nlrp10−/− dendritic cells (DCs elicited sub-optimal IFNγ production by antigen-specific CD4+ T cells compared to wild-type (WT DCs. In response to T-cell encounter, CD40 ligation or Toll-like receptor 9 stimulation, Nlrp10−/− DCs produced low levels of IL-12, due to a substantial decrease in NF-κB activation. Defective IL-12 production was also evident in vivo and affected IFNγ production by CD4+ T cells. Upon Mycobacterium tuberculosis (Mtb infection, Nlrp10−/− mice displayed diminished T helper 1-cell responses and increased bacterial growth compared to WT mice. These data indicate that NLRP10-mediated IL-12 production by DCs is critical for IFNγ induction in T cells and contributes to promote the host defense against Mtb.

  17. Stream biofilm responses to flow intermittency: from cells to ecosystems

    Directory of Open Access Journals (Sweden)

    Sergi eSabater

    2016-03-01

    Full Text Available Temporary streams are characterized by the alternation of dry and wet hydrological phases, creating both a harsh environment for the biota as well as a high diversity of opportunities for adaptation. These systems are eminently microbial-based during several of these hydrological phases, and those growing on all solid substrata (biofilms accordingly change their physical structure and community composition. Biofilms experience large decreases on cell densities and biomass, both of bacteria and algae, during dryness. Algal and bacterial communities show remarkable decreases in their diversity, at least locally (at the habitat scale. Biofilms also respond with significant physiological plasticity to each of the hydrological changes. The decreasing humidity of the substrata through the drying process, and the changing quantity and quality of organic matter and nutrients available in the stream during that process, causes unequal responses on the biofilm bacteria and algae. Biofilm algae are affected faster than bacteria by the hydric stress, and as a result the ecosystem respiration resists longer than gross primary production to the increasing duration of flow intermittency. This response implies enhancing ecosystem heterotrophy, a pattern that can be exacerbated in temporary streams suffering of longer dry periods under global change.

  18. Acrolein in cigarette smoke inhibits T-cell responses.

    Science.gov (United States)

    Lambert, Cherie; McCue, Jesica; Portas, Mary; Ouyang, Yanli; Li, JiMei; Rosano, Thomas G; Lazis, Alexander; Freed, Brian M

    2005-10-01

    Cigarette smoking inhibits T-cell responses in the lungs, but the immunosuppressive compounds have not been fully identified. Cigarette smoke extracts inhibit IL-2, IFN-gamma, and TNF-alpha production in stimulated lymphocytes obtained from peripheral blood, even when the extracts were diluted 100-fold to 1000-fold. The objective of these studies was to identify the immunosuppressive compounds found in cigarette smoke. Gas chromatography/mass spectroscopy and HPLC were used to identify and quantitate volatile compounds found in cigarette smoke extracts. Bioactivity was measured by viability and production of cytokine mRNA and protein levels in treated human lymphocytes. The vapor phase of the cigarette smoke extract inhibited cytokine production, indicating that the immunosuppressive compounds were volatile. Among the volatile compounds identified in cigarette smoke extracts, only the alpha,beta-unsaturated aldehydes, acrolein (inhibitory concentration of 50% [IC50] = 3 micromol/L) and crotonaldehyde (IC50 = 6 micromol/L), exhibited significant inhibition of cytokine production. Although the levels of aldehydes varied 10-fold between high-tar (Camel) and ultralow-tar (Carlton) extracts, even ultralow-tar cigarettes produced sufficient levels of acrolein (34 micromol/L) to suppress cytokine production by >95%. We determined that the cigarette smoke extract inhibited transcription of cytokine genes. The inhibitory effects of acrolein could be blocked with the thiol compound N-acetylcysteine. The vapor phase from cigarette smoke extracts potently suppresses cytokine production. The compound responsible for this inhibition appears to be acrolein.

  19. Fast Neutrons - LET Distributions and the Response of Mammalian Cells

    Energy Technology Data Exchange (ETDEWEB)

    Bewley, D. K. [Medical Research Council Cyclotron Unit, Hammersmith Hospital, London (United Kingdom)

    1968-03-15

    Distributions of stopping power (LET) are given for four beams of fast neutrons, namely, neutrons of 14.6 MeV, neutrons produced by bombarding a thick beryllium target with 15 MeV deuterons, neutrons of 3 MeV, and fast neutrons produced by bombardment of a {sup 235}U converter plate with thermal neutrons. The track average LET is correlated with mean neutron energy, but the dose average is approximately constant. However, neither of these types of average is expected to have much relevance to radiobiology. Further, specification of a ''biologically effective LET'' depends on the biological test used, and is not solely a function of the radiation quality. An attempt has been made to calculate the response of T.I. kidney cells in tissue culture to these four beams of neutrons, based on their response to charged particles using the track-segment method. The calculated RBE's of the neutron beams are lower than the observed values and the calculated values of the oxygen enhancement ratio are higher. These differences seem too great to be explained by errors in dosimetry and in the calculated LET spectra. The suggestion is made that LET is not an adequate criterion of radiation quality, and that the discrepancies may be explained by more detailed consideration of the part played by delta rays and by heavy recoil tracks of short range. (author)

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

    International Nuclear Information System (INIS)

    Wu Gang; Gu Hongguang; Han Benli; Pei Xuetao

    2002-01-01

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

  1. Differential pulmonic NK and NKT cell responses in Schistosoma japonicum-infected mice.

    Science.gov (United States)

    Cha, Hefei; Qin, Wenjuan; Yang, Quan; Xie, Hongyan; Qu, Jiale; Wang, Mei; Chen, Daixiong; Wang, Fang; Dong, Nuo; Chen, Longhua; Huang, Jun

    2017-02-01

    Natural killer cells (NK cells) and natural killer T cells (NKT cells) play a role in anti-infection, anti-tumor, transplantation immunity, and autoimmune regulation. However, the role of NK and NKT cells during Schistosoma japonicum (S. japonicum) infection has not been widely reported, especially regarding lung infections. The aim of this study was to research the NK and NKT cell response to S. japonicum infection in the lungs of mice. Using immunofluorescent histological analysis, NK and NKT cells were found near pulmonary granulomas. Moreover, flow cytometry revealed that the percentage and number of pulmonic NK cells in S. japonicum-infected mice were significantly increased (P cell number of NKT cells were decreased compared to those of normal mice (P NKT cells was increased after infection (P NKT cells (P cells (P NKT cells significantly increased (P NKT cells (P NKT cell activation during S. japonicum infection.

  2. Targeting the cell stress response of Plasmodium falciparum to overcome artemisinin resistance.

    Directory of Open Access Journals (Sweden)

    Con Dogovski

    2015-04-01

    Full Text Available Successful control of falciparum malaria depends greatly on treatment with artemisinin combination therapies. Thus, reports that resistance to artemisinins (ARTs has emerged, and that the prevalence of this resistance is increasing, are alarming. ART resistance has recently been linked to mutations in the K13 propeller protein. We undertook a detailed kinetic analysis of the drug responses of K13 wild-type and mutant isolates of Plasmodium falciparum sourced from a region in Cambodia (Pailin. We demonstrate that ART treatment induces growth retardation and an accumulation of ubiquitinated proteins, indicative of a cellular stress response that engages the ubiquitin/proteasome system. We show that resistant parasites exhibit lower levels of ubiquitinated proteins and delayed onset of cell death, indicating an enhanced cell stress response. We found that the stress response can be targeted by inhibiting the proteasome. Accordingly, clinically used proteasome inhibitors strongly synergize ART activity against both sensitive and resistant parasites, including isogenic lines expressing mutant or wild-type K13. Synergy is also observed against Plasmodium berghei in vivo. We developed a detailed model of parasite responses that enables us to infer, for the first time, in vivo parasite clearance profiles from in vitro assessments of ART sensitivity. We provide evidence that the clinical marker of resistance (delayed parasite clearance is an indirect measure of drug efficacy because of the persistence of unviable parasites with unchanged morphology in the circulation, and we suggest alternative approaches for the direct measurement of viability. Our model predicts that extending current three-day ART treatment courses to four days, or splitting the doses, will efficiently clear resistant parasite infections. This work provides a rationale for improving the detection of ART resistance in the field and for treatment strategies that can be employed in areas

  3. IgE by itself affects mature rat mast cell preformed and de novo-synthesized mediator release and amplifies mast cell migratory response.

    Directory of Open Access Journals (Sweden)

    Aleksandra Słodka

    Full Text Available BACKGROUND: Immunoglobulin E (IgE binds to high affinity receptor FcεRI numerously expressed on mast cells. Recent findings have revealed that IgE by itself may regulate various aspects of mast cell biology, however, detailed data is still limited. METHODOLOGY/FINDINGS: Here, we have examined the influence of IgE alone, used at different concentrations, on mast cell activity and releasability. For the study we have employed in vivo differentiated mature tissue mast cells isolated from rat peritoneal cavity. Mast cells were exposed to IgE alone and then the release of preformed and de novo-synthesized mediators, surface FcεRI expression and mast cell migratory response were assessed. IgE by itself was found to up-regulate FcεRI expression and activate mast cells to degranulation, as well as de novo synthesis and release of cysteinyl leukotrienes and TNF. We have provided evidence that IgE alone also amplified spontaneous and CCL5- or TNF-induced migration of mast cells. Importantly, IgE was effective only at concentrations ≥ 3 µg/mL. A molecular basis investigation using an array of specific inhibitors showed that Src kinases, PLC/PLA2, MAP kinases (ERK and p38 and PI3K were entirely or partially involved in IgE-induced mast cell response. Furthermore, IgE alone stimulated the phosphorylation of MAP kinases and PI3K in rat mast cells. CONCLUSION: Our results clearly demonstrated that IgE by itself, at higher concentrations, influences mast cell activity and releasability. As there are different conditions when the IgE level is raised it might be supposed that in vivo IgE is one of the important factors modulating mast cell biology within tissues.

  4. Self-recognition specificity expressed by T cells from nude mice. Absence of detectable Ia-restricted T cells in nude mice that do exhibit self-K/D-restricted T cell responses

    International Nuclear Information System (INIS)

    Kruisbeek, A.M.; Davis, M.L.; Matis, L.A.; Longo, D.L.

    1984-01-01

    The presence in athymic nude mice of precursor T cells with self-recognition specificity for either H-2 K/D or H-2 I region determinants was investigated. Chimeras were constructed of lethally irradiated parental mice receiving a mixture of F1 nude mouse (6-8 wk old) spleen and bone marrow cells. The donor inoculum was deliberately not subjected to any T cell depletion procedure, so that any potential major histocompatibility complex-committed precursor T cells were allowed to differentiate and expand in the normal parental recipients. 3 mo after reconstitution, the chimeras were immunized with several protein antigens in complete Freund's adjuvant in the footpads and their purified draining lymph node T cells tested 10 d later for ability to recognize antigen on antigen-presenting cells of either parental haplotype. Also, their spleen and lymph node cells were tested for ability to generate a cytotoxic T lymphocyte (CTL) response to trinitrophenyl (TNP)-modified stimulator cells of either parental haplotype. It was demonstrated that T cell proliferative responses of these F1(nude)----parent chimeras were restricted solely to recognizing parental host I region determinants as self and expressed the Ir gene phenotype of the host. In contrast, CTL responses could be generated (in the presence of interleukin 2) to TNP-modified stimulator cells of either parental haplotype. Thus these results indicate that nude mice which do have CTL with self-specificity for K/D region determinants lack proliferating T cells with self-specificity for I region determinants. These results provide evidence for the concepts that development of the I region-restricted T cell repertoire is strictly an intrathymically determined event and that young nude mice lack the unique thymic elements responsible for education of I region-restricted T cells

  5. WD40-repeat proteins in plant cell wall formation: current evidence and research prospects

    Directory of Open Access Journals (Sweden)

    Gea eGuerriero

    2015-12-01

    Full Text Available The metabolic complexity of living organisms relies on supramolecular protein structures which ensure vital processes, such as signal transduction, transcription, translation and cell wall synthesis. In eukaryotes WD40-repeat (WDR proteins often function as molecular hubs mediating supramolecular interactions. WDR proteins may display a variety of interacting partners and participate in the assembly of complexes involved in distinct cellular functions. In plants, the formation of lignocellulosic biomass involves extensive synthesis of cell wall polysaccharides, a process that requires the assembly of large transmembrane enzyme complexes, intensive vesicle trafficking, interactions with the cytoskeleton, and coordinated gene expression. Because of their function as supramolecular hubs, WDR proteins could participate in each or any of these steps, although to date only few WDR proteins have been linked to the cell wall by experimental evidence. Nevertheless, several potential cell wall-related WDR proteins were recently identified using in silico aproaches, such as analyses of co-expression, interactome and conserved gene neighbourhood. Notably, some WDR genes are frequently genomic neighbours of genes coding for GT2-family polysaccharide synthases in eukaryotes, and this WDR-GT2 collinear microsynteny is detected in diverse taxa. In angiosperms, two WDR genes are collinear to cellulose synthase genes, CESAs, whereas in ascomycetous fungi several WDR genes are adjacent to chitin synthase genes, chs. In this Perspective we summarize and discuss experimental and in silico studies on the possible involvement of WDR proteins in plant cell wall formation. The prospects of biotechnological engineering for enhanced biomass production are discussed.

  6. Compensatory role of Neuroglobin in nervous and non-nervous cancer cells in response to the nutrient deprivation.

    Directory of Open Access Journals (Sweden)

    Marco Fiocchetti

    Full Text Available Environmental factors or adverse growth conditions that may reduce cell function or viability are considered stress. The cell ability to sense and respond to environmental stresses determine its function and survival destiny. We recently defined Neuroglobin (NGB, a heme-protein, as a compensatory protein in the 17β-Estradiol (E2 anti-apoptotic activity and as a sensor of oxidative stress in both neurons and breast cancer cells. Here, the possibility that NGB levels could represent a pivotal regulator of integrated response of cancer cells to stress has been evaluated. Data obtained in neuroblastoma and in breast cancer cell lines evidence that nutrient deprivation significantly up-regulated NGB levels at different time points. However, the analysis of autophagy activation led to exclude any possible role of stress- or E2-induced NGB in the upstream regulation of general autophagy. However, the over-expression of Flag-NGB in ERα stable transfected HEK-293 cells completely affects nutrient deprivation-induced decrease in cell number. In addition, reported results indicate that modulation of the anti-apoptotic Bcl-2 level may play a key role in the protective NGB function against energetic stress. Overall, these data define a role of NGB as compensatory protein in the cell machinery activated in response to stress and as general stress adaptation marker of cancer cells susceptible to oxidative stress, oxygen and, as demonstrated here for the first time, even to nutrient willingness. Despite the lacking of any direct NGB role on autophagic flux activated by energetic stress, NGB upregulation appears functional in delaying stress-related cell death allowing an appropriate cell response and adaptation to the changing extracellular conditions.

  7. Transformation by Oncogenic Ras Expands the Early Genomic Response to Transforming Growth Factor β in Intestinal Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Carl E. Allen

    2008-10-01

    Full Text Available A substantial body of evidence implicates TGFβ as a tumor promoter in epithelial cells that have become resistant to its tumor suppressor activity. To better understand early, genome-wide TGFβ responses in cells resistant to growth inhibition by TGFβ, we used microarray analysis in a well-defined cell culture system of sensitive and resistant intestinal epithelial cells. TGFβ-regulated gene expression in TGFβ-growth-sensitive, nontransformed rat intestinal epithelial cells (RIE-1 was compared to expression in TGFβ-growth-resistant RIE cells stably transformed by oncogenic Ras(12V. Treatment of RIE-1 cells with 2 ng/ml TGFβ1 for 1 hour increased the expression of eight gene sequences by 2.6-fold or more, whereas eight were down regulated 2.6-fold. In RIE-Ras(12V cells, 42 gene sequences were upregulated and only 3 were down-regulated. Comparison of RIE and RIE-Ras(12V identified 37 gene sequences as unique, Ras-dependent genomic targets of TGFβ1. TGFβ-regulation of connective tissue growth factor and vascular endothelial growth factor, two genes up-regulated in RIE-Ras cells and previously implicated in tumor promotion, was independently confirmed and further characterized by Northern analysis. Our data indicate that overexpression of oncogenic Ras in intestinal epithelial cells confers a significantly expanded repertoire of robust, early transcriptional responses to TGFβ via signaling pathways yet to be fully elucidated but including the canonical Raf-1/MAPK/Erk pathway. Loss of sensitivity to growth inhibition by TGFβ does not abrogate TGFβ signaling and actually expands the early transcriptional response to TGFβ1. Expression of some of these genes may confer to Ras-transformed cells characteristics favorable for tumor promotion.

  8. 3D culture of Her2+ breast cancer cells promotes AKT to MAPK switching and a loss of therapeutic response.

    Science.gov (United States)

    Gangadhara, Sharath; Smith, Chris; Barrett-Lee, Peter; Hiscox, Stephen

    2016-06-01

    The Her2 receptor is overexpressed in up to 25 % of breast cancers and is associated with a poor prognosis. Around half of Her2+ breast cancers also express the estrogen receptor and treatment for such tumours can involve both endocrine and Her2-targeted therapies. However, despite preclinical data supporting the effectiveness of these agents, responses can vary widely in the clinical setting. In light of the increasing evidence pointing to the interplay between the tumour and its extracellular microenvironment as a significant determinant of therapeutic sensitivity and response here we investigated the impact of 3D matrix culture of breast cancer cells on their therapeutic sensitivity. A 3D Matrigel-based culture system was established and optimized for the growth of ER+/Her2+ breast cancer cell models. Growth of cells in response to trastuzumab and endocrine agents in 3D culture versus routine monolayer culture were assessed using cell counting and Ki67 staining. Endogenous and trastuzumab-modulated signalling pathway activity in 2D and 3D cultures were assessed using Western blotting. Breast cancer cells in 3D culture displayed an attenuated response to both endocrine agents and trastuzumab compared with cells cultured in traditional 2D monolayers. Underlying this phenomenon was an apparent matrix-induced shift from AKT to MAPK signalling; consequently, suppression of MAPK in 3D cultures restores therapeutic response. These data suggest that breast cancer cells in 3D culture display a reduced sensitivity to therapeutic agents which may be mediated by internal MAPK-mediated signalling. Targeting of adaptive pathways that maintain growth in 3D culture may represent an effective strategy to improve therapeutic response clinically.

  9. Sharing experiences: towards an evidence based model of dengue surveillance and outbreak response in Latin America and Asia.

    OpenAIRE

    Badurdeen, Shiraz; Valladares, David; Farrar, Jeremy; Gozzer, Ernesto; Kroeger, Axel; Kuswara, Novia; Ranzinger, Silvia; Tinh, Hien; Leite, Priscila; Mahendradhata, Yodi; Skewes, Ronald; Verrall, Ayesha

    2013-01-01

    BACKGROUND\\ud The increasing frequency and intensity of dengue outbreaks in endemic and non-endemic countries requires a rational, evidence based response. To this end, we aimed to collate the experiences of a number of affected countries, identify strengths and limitations in dengue surveillance, outbreak preparedness, detection and response and contribute towards the development of a model contingency plan adaptable to country needs.\\ud \\ud METHODS\\ud The study was undertaken in five Latin ...

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

    DEFF Research Database (Denmark)

    Riber, Ulla; Jungersen, Gregers

    2007-01-01

    Due to almost identical lipopolysaccharide (LPS) O-antigens, infections with Yersinia enterocolitica serotype 0:9 (YeO:9) cause false positive serological reactions (FPSR) in tests for Brucella and thus cause problems in National Brucella surveillance programs. As LPS are strong inducers...... of antibody responses it was hypothesized that cell-mediated immune responses to non-LPS antigens of the two bacteria can be used to separate immune responses to these two biologically very different infections. Following subclinical experimental infections with Brucella suis biovar 2, high interferon......-gamma (IFN-gamma) assay responses with a commercial Brucella melitensis antigen preparation (Brucellergene OCB) preceded the development of antibodies. High IFN-gamma responses in the seven B. suis inoculated pigs with serological evidence of infection were consistent throughout a 20-week postinoculation...

  11. Murine scid cells complement ataxia-telangiectasia cells and show a normal port-irradiation response of DNA synthesis

    International Nuclear Information System (INIS)

    Komatsu, K.; Yoshida, M.; Okumura, Y.

    1993-01-01

    The murine severe combined immunodeficient mutation (scid) is characterized by a lack of both B and T cells, due to a deficit in lymphoid variable-(diversity)-joining (V(D)J) rearrangement. Scid cells are highly sensitive to both radiation-induced killing and chromosomal aberrations. Significantly reduced D 0 and n values were demonstrated in scid cells and were similar to ataxia-telangiectasia (AT) cells (a unique human disease conferring whole body radiosensitivity). However, the kinetics of DNA synthesis after irradiation were different between the two cell types. In contrast with the radioresistant DNA synthesis of AT cells, DNA synthesis of scid cells was markedly inhibited after irradiation. The existence of different mutations was also supported by evidence of complementation in somatic cell hybrids between scid cells and AT cells. Results indicate that the radiobiological character of scid is similar to AT but is presumably caused by different mechanisms. (author)

  12. HLA-E-expressing pluripotent stem cells escape allogeneic responses and lysis by NK cells.

    Science.gov (United States)

    Gornalusse, Germán G; Hirata, Roli K; Funk, Sarah E; Riolobos, Laura; Lopes, Vanda S; Manske, Gabriel; Prunkard, Donna; Colunga, Aric G; Hanafi, Laïla-Aïcha; Clegg, Dennis O; Turtle, Cameron; Russell, David W

    2017-08-01

    Polymorphisms in the human leukocyte antigen (HLA) class I genes can cause the rejection of pluripotent stem cell (PSC)-derived products in allogeneic recipients. Disruption of the Beta-2 Microglobulin (B2M) gene eliminates surface expression of all class I molecules, but leaves the cells vulnerable to lysis by natural killer (NK) cells. Here we show that this 'missing-self' response can be prevented by forced expression of minimally polymorphic HLA-E molecules. We use adeno-associated virus (AAV)-mediated gene editing to knock in HLA-E genes at the B2M locus in human PSCs in a manner that confers inducible, regulated, surface expression of HLA-E single-chain dimers (fused to B2M) or trimers (fused to B2M and a peptide antigen), without surface expression of HLA-A, B or C. These HLA-engineered PSCs and their differentiated derivatives are not recognized as allogeneic by CD8 + T cells, do not bind anti-HLA antibodies and are resistant to NK-mediated lysis. Our approach provides a potential source of universal donor cells for applications where the differentiated derivatives lack HLA class II expression.

  13. HLA-E-expressing pluripotent stem cells escape allogeneic responses and lysis by NK cells

    Science.gov (United States)

    Gornalusse, Germán G.; Hirata, Roli K.; Funk, Sarah; Riolobos, Laura; Lopes, Vanda S.; Manske, Gabriel; Prunkard, Donna; Colunga, Aric G.; Hanafi, Laïla-Aïcha; Clegg, Dennis O.; Turtle, Cameron; Russell, David W.

    2017-01-01

    Polymorphisms in the human leukocyte antigen (HLA) class I genes can cause the rejection of pluripotent stem cell (PSC)-derived products in allogeneic recipients. Disruption of the Beta-2 Microglobulin (B2M) gene eliminates surface expression of all class I molecules, but leaves the cells vulnerable to lysis by natural killer (NK) cells. Here we show that this ‘missing self’ response can be prevented by forced expression of minimally polymorphic HLA-E molecules. We use adeno-associated virus (AAV)-mediated gene editing to knock in HLA-E genes at the B2M locus in human PSCs in a manner that confers inducible, regulated, surface expression of HLA-E single-chain dimers (fused to B2M) or trimers (fused to B2M and a peptide antigen), without surface expression of HLA-A, B or C. These HLA-engineered PSCs and their differentiated derivatives are not recognized as allogeneic by CD8+ T cells, do not bind anti-HLA antibodies, and are resistant to NK-mediated lysis. Our approach provides a potential source of universal donor cells for applications where the differentiated derivatives lack HLA class II expression. PMID:28504668

  14. Fibroblast and T cells conditioned media induce maturation dendritic cell and promote T helper immune response

    Directory of Open Access Journals (Sweden)

    Masoumeh Asadi

    2012-06-01

    Full Text Available Dendritic cells (DCs induce pathogen-specific T cell responses. We comprehensively studied the effects of addition of maturation stimulus, fibroblasts (fibroblast conditioned medium, PHA activated T cells (T cell conditioned medium, and mixture of fibroblast & PHA activated T cells (FCM-TCCM conditioned media on maturation of DCs. Monocytes were cultured with GM-CSF and IL-4 for five days. Maturation factors included MCM and TNF-α as control group. FCM and TCCM, or FCM-TCCM supernatant were considered as the treatment group. Tumor antigens were added at day five. Matured DCs were harvested at day seven. Phenotypic and functional analyses were carried out using anti (CD14, CD80, CD86, CD83 and HLA-DR monoclonal antibodies. Phagocytic activity, mixed lymphocyte reaction (MLR and cytokine production were also evaluated. At the end of culturing period, significantly fully matured DCs with large amount cytoplasm and copious dendritic projections were found in the presence of MCM, TNF-α with or without FCM, TCCM, FCM as well as TCCM. Flow cytometric analysis revealed that expression of CD14 decreased in particular in treated DCs, at the 5th day and expression of CD80, CD86 and HLA-DR was higher when FCM, TCCM, FCM plus TCCM were added to maturation factor. This study demonstrated that DCs matured with these methods had optimum function in comparison with either factor alone.

  15. Proliferative responses in the local lymph node assay associated with concomitant exposure to 1,4-phenylenediamine and methyldibromo glutaronitrile: evidence for synergy?

    Science.gov (United States)

    Jowsey, Ian R; Basketter, David A; Irwin, Anita

    2008-08-01

    A key consideration when undertaking risk assessments should be the potential for synergy between contact allergens. Previously, this concept has only been investigated during elicitation in contact allergic individuals. To determine whether there exists evidence for synergy between contact allergens during the induction phase of skin sensitization using the mouse local lymph node assay (LLNA) as a model system. Proliferative responses in draining lymph nodes were assessed with increasing concentrations of 1,4-phenylenediamine (PPD), methyldibromo glutaronitrile (MDBGN), and a combination of PPD and MDBGN. Data from each of two independent experiments show that lymph node cell proliferation associated with combined exposure to PPD and MDBGN was, in general, only modestly increased relative to that predicted from a simple summation of their individual responses. Although the increase in response is very modest, it does imply a relationship between this combination of sensitizers that may not be simply additive in terms of their ability to stimulate proliferative responses in draining lymph nodes. The reproducibility of this observation should be confirmed in future studies with additional pairs of contact allergens to ascertain whether or not this represents evidence of synergy.

  16. B-Cell and T-Cell Immune Responses to Experimental Helicobacter pylori Infection in Humans

    Science.gov (United States)

    Nurgalieva, Zhannat Z.; Conner, Margaret E.; Opekun, Antone R.; Zheng, Carl Q.; Elliott, Susan N.; Ernst, Peter B.; Osato, Michael; Estes, Mary K.; Graham, David Y.

    2005-01-01

    The acute antibody and T-cell immune response to Helicobacter pylori infection in humans has not been studied systematically. Serum from H. pylori-naive volunteers challenged with H. pylori and cured after 4 or 12 weeks was tested by enzyme-linked immunosorbent assays for anti-H. pylori-specific immunoglobulin M (IgM) and IgA established using bacterial lysates from homologous (the infecting strain) and heterologous H. pylori. Proteins recognized by IgM antibody were identified by mass spectrometry of immunoreactive bands separated by two-dimensional gel electrophoresis. Mucosal T-cell subsets (CD4, CD8, CD3, and CD30 cells) were assessed by immunohistochemistry. All 18 infected volunteers developed H. pylori-specific IgM responses to both homologous or heterologous H. pylori antigens. H. pylori antigens reacted with IgM antibody at 4 weeks postinfection. IgM Western blotting showed immunoreactivity of postinfection serum samples to multiple H. pylori proteins with molecular weights ranging between 9,000 (9K) to 150K with homologous strains but only a 70K band using heterologous antigens. Two-dimensional electrophoresis demonstrated that production of H. pylori-specific IgM antibodies was elicited by H. pylori flagellins A and B, urease B, ABC transporter binding protein, heat shock protein 70 (DnaK), and alkyl hydroperoxide reductase. Mucosal CD3, CD4, and CD8 T-cell numbers increased following infection. IgM antibody responses were detected to a range of homologous H. pylori antigens 2 to 4 weeks postchallenge. The majority of H. pylori proteins were those involved in motility and colonization and may represent targets for vaccine development. PMID:15845507

  17. Metabolomics Analysis of Hormone-Responsive and Triple-Negative Breast Cancer Cell Responses to Paclitaxel Identify Key Metabolic Differences.

    Science.gov (United States)

    Stewart, Delisha A; Winnike, Jason H; McRitchie, Susan L; Clark, Robert F; Pathmasiri, Wimal W; Sumner, Susan J

    2016-09-02

    To date, no targeted therapies are available to treat triple negative breast cancer (TNBC), while other breast cancer subtypes are responsive to current therapeutic treatment. Metabolomics was conducted to reveal differences in two hormone receptor-negative TNBC cell lines and two hormone receptor-positive Luminal A cell lines. Studies were conducted in the presence and absence of paclitaxel (Taxol). TNBC cell lines had higher levels of amino acids, branched-chain amino acids, nucleotides, and nucleotide sugars and lower levels of proliferation-related metabolites like choline compared with Luminal A cell lines. In the presence of paclitaxel, each cell line showed unique metabolic responses, with some similarities by type. For example, in the Luminal A cell lines, levels of lactate and creatine decreased while certain choline metabolites and myo-inositol increased with paclitaxel. In the TNBC cell lines levels of glutamine, glutamate, and glutathione increased, whereas lysine, proline, and valine decreased in the presence of drug. Profiling secreted inflammatory cytokines in the conditioned media demonstrated a greater response to paclitaxel in the hormone-positive Luminal cells compared with a secretion profile that suggested greater drug resistance in the TNBC cells. The most significant differences distinguishing the cell types based on pathway enrichment analyses were related to amino acid, lipid and carbohydrate metabolism pathways, whereas several biological pathways were differentiated between the cell lines following treatment.

  18. Distinct Responses of Stem Cells to Telomere Uncapping-A Potential Strategy to Improve the Safety of Cell Therapy.

    Science.gov (United States)

    Liu, Chang Ching; Ma, Dong Liang; Yan, Ting-Dong; Fan, XiuBo; Poon, Zhiyong; Poon, Lai-Fong; Goh, Su-Ann; Rozen, Steve G; Hwang, William Ying Khee; Tergaonkar, Vinay; Tan, Patrick; Ghosh, Sujoy; Virshup, David M; Goh, Eyleen L K; Li, Shang

    2016-10-01

    In most human somatic cells, the lack of telomerase activity results in progressive telomere shortening during each cell division. Eventually, DNA damage responses triggered by critically short telomeres induce an irreversible cell cycle arrest termed replicative senescence. However, the cellular responses of human pluripotent stem cells to telomere uncapping remain unknown. We generated telomerase knockout human embryonic stem (ES) cells through gene targeting. Telomerase inactivation in ES cells results in progressive telomere shortening. Telomere DNA damage in ES cells and neural progenitor cells induces rapid apoptosis when telomeres are uncapped, in contrast to fibroblast cells that enter a state of replicative senescence. Significantly, telomerase inactivation limits the proliferation capacity of human ES cells without affecting their pluripotency. By targeting telomerase activity, we can functionally separate the two unique properties of human pluripotent stem cells, namely unlimited self-renewal and pluripotency. We show that the potential of ES cells to form teratomas in vivo is dictated by their telomere length. By controlling telomere length of ES cells through telomerase inactivation, we can inhibit teratoma formation and potentially improve the safety of cell therapies involving terminally differentiated cells as well as specific progenitor cells that do not require sustained cellular proliferation in vivo, and thus sustained telomerase activity. Stem Cells 2016;34:2471-2484. © 2016 AlphaMed Press.

  19. Lead Intoxication Synergies of the Ethanol-Induced Toxic Responses in Neuronal Cells--PC12.

    Science.gov (United States)

    Kumar, V; Tripathi, V K; Jahan, S; Agrawal, M; Pandey, A; Khanna, V K; Pant, A B

    2015-12-01

    Lead (Pb)-induced neurodegeneration and its link with widespread neurobehavioral changes are well documented. Experimental evidences suggest that ethanol could enhance the absorption of metals in the body, and alcohol consumption may increase the susceptibility to metal intoxication in the brain. However, the underlying mechanism of ethanol action in affecting metal toxicity in brain cells is poorly understood. Thus, an attempt was made to investigate the modulatory effect of ethanol on Pb intoxication in PC12 cells, a rat pheochromocytoma. Cells were co-exposed to biological safe doses of Pb (10 μM) and ethanol (200 mM), and data were compared to the response of cells which received independent exposure to these chemicals at similar doses. Ethanol (200 mM) exposure significantly aggravated the Pb-induced alterations in the end points associated with oxidative stress and apoptosis. The finding confirms the involvement of reactive oxygen species (ROS)-mediated oxidative stress, and impairment of mitochondrial membrane potential, which subsequently facilitate the translocation of triggering proteins between cytoplasm and mitochondria. We further confirmed the apoptotic changes due to induction of mitochondria-mediated caspase cascade. These cellular changes were found to recover significantly, if the cells are exposed to N-acetyl cysteine (NAC), a known antioxidant. Our data suggest that ethanol may potentiate Pb-induced cellular damage in brain cells, but such damaging effects could be recovered by inhibition of ROS generation. These results open up further possibilities for the design of new therapeutics based on antioxidants to prevent neurodegeneration and associated health problems.

  20. Impaired replication stress response in cells from immunodeficiency patients carrying Cernunnos/XLF mutations.

    Directory of Open Access Journals (Sweden)

    Michal Schwartz

    Full Text Available Non-Homologous End Joining (NHEJ is one of the two major pathways of DNA Double Strand Breaks (DSBs repair. Mutations in human NHEJ genes can lead to immunodeficiency due to its role in V(DJ recombination in the immune system. In addition, most patients carrying mutations in NHEJ genes display developmental anomalies which are likely the result of a general defect in repair of endogenously induced DSBs such as those arising during normal DNA replication. Cernunnos/XLF is a recently identified NHEJ gene which is mutated in immunodeficiency with microcephaly patients. Here we aimed to investigate whether Cernunnos/XLF mutations disrupt the ability of patient cells to respond to replication stress conditions. Our results demonstrate that Cernunnos/XLF mutated cells and cells downregulated for Cernunnos/XLF have increased sensitivity to conditions which perturb DNA replication. In addition, under replication stress, these cells exhibit impaired DSB repair and increased accumulation of cells in G2/M. Moreover Cernunnos/XLF mutated and down regulated cells display greater chromosomal instability, particularly at fragile sites, under replication stress conditions. These results provide evidence for the role of Cernunnos/XLF in repair of DSBs and maintenance of genomic stability under replication stress conditions. This is the first study of a NHEJ syndrome showing association with impaired cellular response to replication stress conditions. These findings may be related to the clinical features in these patients which are not due to the V(DJ recombination defect. Additionally, in light of the emerging important role of replication stress in the early stages of cancer development, our findings may provide a mechanism for the role of NHEJ in preventing tumorigenesis.

  1. Radioadaptive response to the medium-mediated bystander induction of DNA strand breaks in HeLa cells

    International Nuclear Information System (INIS)

    Ikushima, T.; Okuyama, M.

    2003-01-01

    Full text: Numerous investigators have reported two cellular responses of importance at low doses that have a potential impact on the risk estimation of ionizing radiation. The radioadaptive response confers resistance to a subsequent dose by a low priming dose, while the bystander effect exaggerates the effect of small doses. The present study was conducted to examine the interaction of the radioadaptive response with the bystander effect in HeLa cells. The culture was irradiated with 0.5 to 8 Gy of 140 kVp X-rays and one hour later, the medium was taken, passed through a filter and transferred to the parallel culture of non-irradiated HeLa cells as non-targeted cells. After incubation for 30 min, the induced DNA damage was analyzed by the single cell gel-electrophoresis assay under alkaline or neutral conditions. The treatments resulted in a dose-dependent increase in tail moment under either conditions, indicating the induction of DNA single- and double-strand breaks. The clonogenic survival of non-irradiated cells was also reduced after they were cultured in the medium that was taken from irradiated cultures. Any change was not observed when the medium alone was irradiated. These results give the disputed evidence that certain genotoxic factor(s) released from irradiated cells into the culture medium can induce DNA strand breaks leading to cell death. It is also suggested that physical contact between irradiated and non-irradiated cells may not be required for the bystander effect. In adapted cells that were pre-exposed to 5 cGy of X-rays and cultured for 4 h beforehand, the yield of DNA strand breaks induced by X-rayed medium was reduced by about 50 %. The results, in conjunction with our early finding (Ikushima et al., 1996) suggest that the radioadaptive response resulting from such a low dose may diminish the bystander effect through an enhanced DNA repair function

  2. Cellular cooperation in lymphocyte activation. III. B-cell helper effect in the enhancement of T-cell response.

    Science.gov (United States)

    Kasahara, T; Kin, K; Itoh, Y; Kawai, T; Kano, Y; Shioiri-Nakano, K

    1979-01-01

    T and B cells were purified from human tonsil and peripheral blood by the removal of phagocytic cells, followed by filtration through a nylon fiber column (NC) and E-rosette formation. Purified T and B cells contained less than 1% of other cell types. The responses of T cells to concanavalin A (Con A) and soluble protein A were greatly enhanced in the presence of autologous B cells. Participation of B cells in T-cell enhancement was confirmed by the following observations: (a) purified B copulation, which was separated further from adherent B cells, retained its enhancing activity. (b) Another adherent cell-free B-cell preparation, which was purified from the NC-passed fraction, and (c) no T lymphoid but some B lymphoid cell lines, elicited strong T-cell enhancement. It was also found that the enhancing capacity of B cells required no metabolic activity, but rather an intact cell form and direct cell-to-cell contact with responding cells. The stimulatory determinants on B cells were resistant to trypsin and neuraminidase treatment. In this paper a hypothesis will be presented that at least two signals are prerequisite for the effective activation of T cells.

  3. Analyses of Potential Predictive Markers and Response to Targeted Therapy in Patients with Advanced Clear-cell Renal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Yan Song

    2015-01-01

    Full Text Available Background: Vascular endothelial growth factor-targeted agents are standard treatments in advanced clear-cell renal cell carcinoma (ccRCC, but biomarkers of activity are lacking. The aim of this study was to investigate the association of Von Hippel-Lindau (VHL gene status, vascular endothelial growth factor receptor (VEGFR or stem cell factor receptor (KIT expression, and their relationships with characteristics and clinical outcome of advanced ccRCC. Methods: A total of 59 patients who received targeted treatment with sunitinib or pazopanib were evaluated for determination at Cancer Hospital and Institute, Chinese Academy of Medical Sciences between January 2010 and November 2012. Paraffin-embedded tumor samples were collected and status of the VHL gene and expression of VEGFR and KIT were determined by VHL sequence analysis and immunohistochemistry. Clinical-pathological features were collected and efficacy such as response rate and Median progression-free survival (PFS and overall survival (OS were calculated and then compared based on expression status. The Chi-square test, the Kaplan-Meier method, and the Lon-rank test were used for statistical analyses. Results: Of 59 patients, objective responses were observed in 28 patients (47.5%. The median PFS was 13.8 months and median OS was 39.9 months. There was an improved PFS in patients with the following clinical features: Male gender, number of metastatic sites 2 or less, VEGFR-2 positive or KIT positive. Eleven patients (18.6% had evidence of VHL mutation, with an objective response rate of 45.5%, which showed no difference with patients with no VHL mutation (47.9%. VHL mutation status did not correlate with either overall response rate (P = 0.938 or PFS (P = 0.277. The PFS was 17.6 months and 22.2 months in VEGFR-2 positive patients and KIT positive patients, respectively, which was significantly longer than that of VEGFR-2 or KIT negative patients (P = 0.026 and P = 0.043. Conclusion

  4. Screening tool for oropharyngeal dysphagia in stroke - Part I: evidence of validity based on the content and response processes.

    Science.gov (United States)

    Almeida, Tatiana Magalhães de; Cola, Paula Cristina; Pernambuco, Leandro de Araújo; Magalhães, Hipólito Virgílio; Magnoni, Carlos Daniel; Silva, Roberta Gonçalves da

    2017-08-17

    The aim of the present study was to identify the evidence of validity based on the content and response process of the Rastreamento de Disfagia Orofaríngea no Acidente Vascular Encefálico (RADAVE; "Screening Tool for Oropharyngeal Dysphagia in Stroke"). The criteria used to elaborate the questions were based on a literature review. A group of judges consisting of 19 different health professionals evaluated the relevance and representativeness of the questions, and the results were analyzed using the Content Validity Index. In order to evidence validity based on the response processes, 23 health professionals administered the screening tool and analyzed the questions using a structured scale and cognitive interview. The RADAVE structured to be applied in two stages. The first version consisted of 18 questions in stage I and 11 questions in stage II. Eight questions in stage I and four in stage II did not reach the minimum Content Validity Index, requiring reformulation by the authors. The cognitive interview demonstrated some misconceptions. New adjustments were made and the final version was produced with 12 questions in stage I and six questions in stage II. It was possible to develop a screening tool for dysphagia in stroke with adequate evidence of validity based on content and response processes. Both validity evidences obtained so far allowed to adjust the screening tool in relation to its construct. The next studies will analyze the other evidences of validity and the measures of accuracy.

  5. Ionizing radiation affects generation of MART-1-specific cytotoxic T cell responses by dendritic cells

    International Nuclear Information System (INIS)

    Liao, Y.P.; Wang, C.-C.; McBride, W.H.

    2003-01-01

    Full text: The human MART-1/Melan-A (MART-1) melanoma tumor antigen is known to be recognized by cytotoxic T lymphocytes (CTLs) and several groups are using this target for clinical immunotherapy. Most approaches use dendritic cells (DCs) that are potent antigen presentation cells for initiating CTL responses. In order for CTL recognition to occur, DCs must display 9-residue antigenic peptides on MHC class I molecules. These peptides are generated by proteasome degradation and then transported through the endoplasmic reticulum to the cell surface where they stabilize MHC class I expression. Our previous data showed that irradiation inhibits proteasome function and, therefore, we hypothesized that irradiation may inhibit antigen processing and CTL activation, as has been shown for proteasome inhibitors. To study the importance of irradiation effects on DCs, we studied the generation MART-1-specific CTL responses. Preliminary data showed that irradiation of murine bone marrow derived DCs did not affect expression of MHC class I, II, CD80, or CD86, as assessed by flow cytometric analyses 24-hour after irradiation. The effect of irradiation on MART-1 antigen processing by DCs was evaluated using DC transduced with adenovirus MART-1 (AdVMART1). C57BL/6 mice were immunized with AdVMART1 transduced DCs, with and without prior irradiation. IFN-γ production was measured by ELISPOT assays after 10-14 days of immunization. Prior radiation treatment resulted in a significant decrease in MART-1-specific T cell responses. The ability of irradiated and non-irradiated AdVMART1/DC vaccines to protect mice against growth of murine B16 tumors, which endogenously express murine MART-1, was also examined. AdVMART1/DC vaccination protected C57BL/6 mice against challenge with viable B16 melanoma cells while DCs irradiated (10 Gy) prior to AdVMART1 transduction abrogated protection. These results suggest that proteasome inhibition in DCs by irradiation may be a possible pathway in

  6. Response of thyroid follicular cells to gamma irradiation compared to proton irradiation. I. Initial characterization of DNA damage, micronucleus formation, apoptosis, cell survival, and cell cycle phase redistribution

    Science.gov (United States)

    Green, L. M.; Murray, D. K.; Bant, A. M.; Kazarians, G.; Moyers, M. F.; Nelson, G. A.; Tran, D. T.

    2001-01-01

    The RBE of protons has been assumed to be equivalent to that of photons. The objective of this study was to determine whether radiation-induced DNA and chromosome damage, apoptosis, cell killing and cell cycling in organized epithelial cells was influenced by radiation quality. Thyroid-stimulating hormone-dependent Fischer rat thyroid cells, established as follicles, were exposed to gamma rays or proton beams delivered acutely over a range of physical doses. Gamma-irradiated cells were able to repair DNA damage relatively rapidly so that by 1 h postirradiation they had approximately 20% fewer exposed 3' ends than their counterparts that had been irradiated with proton beams. The persistence of free ends of DNA in the samples irradiated with the proton beam implies that either more initial breaks or a quantitatively different type of damage had occurred. These results were further supported by an increased frequency of chromosomal damage as measured by the presence of micronuclei. Proton-beam irradiation induced micronuclei at a rate of 2.4% per gray, which at 12 Gy translated to 40% more micronuclei than in comparable gamma-irradiated cultures. The higher rate of micronucleus formation and the presence of larger micronuclei in proton-irradiated cells was further evidence that a qualitatively more severe class of damage had been induced than was induced by gamma rays. Differences in the type of damage produced were detected in the apoptosis assay, wherein a significant lag in the induction of apoptosis occurred after gamma irradiation that did not occur with protons. The more immediate expression of apoptotic cells in the cultures irradiated with the proton beam suggests that the damage inflicted was more severe. Alternatively, the cell cycle checkpoint mechanisms required for recovery from such damage might not have been invoked. Differences based on radiation quality were also evident in the alpha components of cell survival curves (0.05 Gy(-1) for gamma rays, 0

  7. Mesenchymal Stem Cells and Cutaneous Wound Healing: Current Evidence and Future Potential

    Directory of Open Access Journals (Sweden)

    M. Isakson

    2015-01-01

    Full Text Available Human skin is a remarkable organ that sustains insult and injury throughout life. The ability of skin to expeditiously repair wounds is paramount to survival. With an aging global population, coupled with a rise in the prevalence of conditions such as diabetes, chronic wounds represent a significant biomedical burden. Mesenchymal stem cells (MSC, a progenitor cell population of the mesoderm lineage, have been shown to be significant mediators in inflammatory environments. Preclinical studies of MSC in various animal wound healing models point towards a putative therapy. This review examines the body of evidence suggesting that MSC accelerate wound healing in both clinical and preclinical studies and also the possible mechanisms controlling its efficacy. The delivery of a cellular therapy to the masses presents many challenges from a safety, ethical, and regulatory point of view. Some of the issues surrounding the introduction of MSC as a medicinal product are also delineated in this review.

  8. Inhibition of host cell translation elongation by Legionella pneumophila blocks the host cell unfolded protein response.

    Science.gov (United States)

    Hempstead, Andrew D; Isberg, Ralph R

    2015-12-08

    Cells of the innate immune system recognize bacterial pathogens by detecting common microbial patterns as well as pathogen-specific activities. One system that responds to these stimuli is the IRE1 branch of the unfolded protein response (UPR), a sensor of endoplasmic reticulum (ER) stress. Activation of IRE1, in the context of Toll-like receptor (TLR) signaling, induces strong proinflammatory cytokine induction. We show here that Legionella pneumophila, an intravacuolar pathogen that replicates in an ER-associated compartment, blocks activation of the IRE1 pathway despite presenting pathogen products that stimulate this response. L. pneumophila TLR ligands induced the splicing of mRNA encoding XBP1s, the main target of IRE1 activity. L. pneumophila was able to inhibit both chemical and bacterial induction of XBP1 splicing via bacterial translocated proteins that interfere with host protein translation. A strain lacking five translocated translation elongation inhibitors was unable to block XBP1 splicing, but this could be rescued by expression of a single such inhibitor, consistent with limitation of the response by translation elongation inhibitors. Chemical inhibition of translation elongation blocked pattern recognition receptor-mediated XBP1 splicing, mimicking the effects of the bacterial translation inhibitors. In contrast, host cell-promoted inhibition of translation initiation in response to the pathogen was ineffective in blocking XBP1 splicing, demonstrating the need for the elongation inhibitors for protection from the UPR. The inhibition of host translation elongation may be a common strategy used by pathogens to limit the innate immune response by interfering with signaling via the UPR.

  9. Target or barrier? The cell wall of early- and later- diverging plants vs cadmium toxicity: differences in the response mechanisms

    Directory of Open Access Journals (Sweden)

    Luigi eParrotta

    2015-03-01

    Full Text Available Increasing industrialization and urbanization result in emission of pollutants in the environment including toxic heavy metals, as cadmium and lead. Among the different heavy metals contaminating the environment, cadmium raises great concern, as it is ecotoxic and as such can heavily impact ecosystems. The cell wall is the first structure of plant cells to come in contact with heavy metals. Its composition, characterized by proteins, polysaccharides and in some instances lignin and other phenolic compounds, confers the ability to bind non-covalently and/or covalently heavy metals via functional groups. A strong body of evidence in the literature has shown the role of the cell wall in heavy metal response: it sequesters heavy metals, but at the same time its synthesis and composition can be severely affected. The present review analyzes the dual property of plant cell walls, i.e. barrier and target of heavy metals, by taking Cd toxicity as example. Following a summary of the known physiological and biochemical responses of plants to Cd, the review compares the wall-related mechanisms in early- and later-diverging land plants, by considering the diversity in cell wall composition. By doing so, common as well as unique response mechanisms to metal/cadmium toxicity are identified among plant phyla and discussed. After discussing the role of hyperaccumulators’ cell walls as a particular case, the review concludes by considering important aspects for plant engineering.

  10. Application of laser tweezers Raman spectroscopy techniques to the monitoring of single cell response to stimuli

    Science.gov (United States)

    Chan, James W.; Liu, Rui; Matthews, Dennis L.

    2012-06-01

    Laser tweezers Raman spectroscopy (LTRS) combines optical trapping with micro-Raman spectroscopy to enable label-free biochemical analysis of individual cells and small biological particles in suspension. The integration of the two technologies greatly simplifies the sample preparation and handling of suspension cells for spectroscopic analysis in physiologically meaningful conditions. In our group, LTRS has been used to study the effects of external perturbations, both chemical and mechanical, on the biochemistry of the cell. Single cell dynamics can be studied by performing longitudinal studies to continuously monitor the response of the cell as it interacts with its environment. The ability to carry out these measurements in-vitro makes LTRS an attractive tool for many biomedical applications. Here, we discuss the use of LTRS to study the response of cancer cells to chemotherapeutics and bacteria cells to antibiotics and show that the life cycle and apoptosis of the cells can be detected. These results show the promise of LTRS for drug discovery/screening, antibiotic susceptibility testing, and chemotherapy response monitoring applications. In separate experiments, we study the response of red blood cells to the mechanical forces imposed on the cell by the optical tweezers. A laser power dependent deoxygenation of the red blood cell in the single beam trap is reported. Normal, sickle cell, and fetal red blood cells have a different behavior that enables the discrimination of the cell types based on this mechanochemical response. These results show the potential utility of LTRS for diagnosing and studying red blood cell diseases.

  11. T-cell-independent immune responses do not require CXC ligand 13-mediated B1 cell migration.

    Science.gov (United States)

    Colombo, Matthew J; Sun, Guizhi; Alugupalli, Kishore R

    2010-09-01

    The dynamic movement of B cells increases the probability of encountering specific antigen and facilitates cell-cell interactions required for mounting a rapid antibody response. B1a and B1b cells are enriched in the coelomic cavity, contribute to T-cell-independent (TI) antibody responses, and increase in number upon antigen exposure. B1 cell movement is largely governed by Cxc ligand 13 (Cxcl13), and mice deficient in this chemokine have a severe reduction in peritoneal B1 cells. In this study, we examined the role of Cxcl13-dependent B cell migration using Borrelia hermsii infection or intraperitoneal immunization with pneumococcal polysaccharide or 4-hydroxy-3-nitrophenyl-acetyl (NP)-Ficoll, all of which induce robust antibody responses from B1b cells. Surprisingly, we found that antibody responses to B. hermsii or to FhbA, an antigenic target of B1b cells, and the resolution of bacteremia were indistinguishable between wild-type and Cxcl13-/- mice. Importantly, we did not observe an expansion of peritoneal B1b cell numbers in Cxcl13-/- mice. Nonetheless, mice that had resolved infection were resistant to reinfection, indicating that the peritoneal B1b cell reservoir is not required for controlling B. hermsii. Furthermore, despite a reduced peritoneal B1b compartment, immunization with pneumococcal polysaccharide vaccine yielded comparable antigen-specific antibody responses in wild-type and Cxcl13-/- mice and conferred protection against Streptococcus pneumoniae. Likewise, immunization with NP-Ficoll elicited similar antibody responses in wild-type and Cxcl13-/- mice. These data demonstrate that homing of B1 cells into the coelomic cavity is not a requirement for generating protective TI antibody responses, even when antigen is initially localized to this anatomical compartment.

  12. Responses of crayfish photoreceptor cells following intense light adaptation.

    Science.gov (United States)

    Cummins, D R; Goldsmith, T H

    1986-01-01

    After intense orange adapting exposures that convert 80% of the rhodopsin in the eye to metarhodopsin, rhabdoms become covered with accessory pigment and appear to lose some microvillar order. Only after a delay of hours or even days is the metarhodopsin replaced by rhodopsin (Cronin and Goldsmith 1984). After 24 h of dark adaptation, when there has been little recovery of visual pigment, the photoreceptor cells have normal resting potentials and input resistances, and the reversal potential of the light response is 10-15 mV (inside positive), unchanged from controls. The log V vs log I curve is shifted about 0.6 log units to the right on the energy axis, quantitatively consistent with the decrease in the probability of quantum catch expected from the lowered concentration of rhodopsin in the rhabdoms. Furthermore, at 24 h the photoreceptors exhibit a broader spectral sensitivity than controls, which is also expected from accumulations of metarhodopsin in the rhabdoms. In three other respects, however, the transduction process appears to be light adapted: The voltage responses are more phasic than those of control photoreceptors. The relatively larger effect (compared to controls) of low extracellular Ca++ (1 mmol/l EGTA) in potentiating the photoresponses suggests that the photoreceptors may have elevated levels of free cytoplasmic Ca++. The saturating depolarization is only about 30% as large as the maximal receptor potentials of contralateral, dark controls, and by that measure the log V-log I curve is shifted downward by 0.54 log units.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Substoichiometric hydroxynonenylation of a single protein recapitulates whole-cell-stimulated antioxidant response.

    Science.gov (United States)

    Parvez, Saba; Fu, Yuan; Li, Jiayang; Long, Marcus J C; Lin, Hong-Yu; Lee, Dustin K; Hu, Gene S; Aye, Yimon

    2015-01-14

    Lipid-derived electrophiles (LDEs) that can directly modify proteins have emerged as important small-molecule cues in cellular decision-making. However, because these diffusible LDEs can modify many targets [e.g., >700 cysteines are modified by the well-known LDE 4-hydroxynonenal (HNE)], establishing the functional consequences of LDE modification on individual targets remains devilishly difficult. Whether LDE modifications on a single protein are biologically sufficient to activate discrete redox signaling response downstream also remains untested. Herein, using T-REX (targetable reactive electrophiles and oxidants), an approach aimed at selectively flipping a single redox switch in cells at a precise time, we show that a modest level (∼34%) of HNEylation on a single target is sufficient to elicit the pharmaceutically important antioxidant response element (ARE) activation, and the resultant strength of ARE induction recapitulates that observed from whole-cell electrophilic perturbation. These data provide the first evidence that single-target LDE modifications are important individual events in mammalian physiology.

  14. Evidence for an evolutionarily conserved interaction between cell wall biosynthesis and flowering in maize and sorghum

    Directory of Open Access Journals (Sweden)

    Thompson Karen J

    2002-01-01

    Full Text Available Abstract Background Factors that affect flowering vary among different plant species, and in the grasses in particular the exact mechanism behind this transition is not fully understood. The brown midrib (bm mutants of maize (Zea mays L., which have altered cell wall composition, have different flowering dynamics compared to their wild-type counterparts. This is indicative of a link between cell wall biogenesis and flowering. In order to test whether this relationship also exists in other grasses, the flowering dynamics in sorghum (Sorghum bicolor (L. Moench were investigated. Sorghum is evolutionarily closely related to maize, and a set of brown midrib (bmr mutants similar to the maize bm mutants is available, making sorghum a suitable choice for study in this context. Results We compared the flowering time (time to half-bloom of several different bmr sorghum lines and their wild-type counterparts. This revealed that the relationship between cell wall composition and flowering was conserved in sorghum. Specifically, the mutant bmr7 flowered significantly earlier than the corresponding wild-type control, whereas the mutants bmr2, bmr4, bmr6, bmr12, and bmr19 flowered later than their wild-type controls. Conclusion The change in flowering dynamics in several of the brown midrib sorghum lines provides evidence for an evolutionarily conserved mechanism that links cell wall biosynthesis to flowering dynamics. The availability of the sorghum bmr mutants expands the germplasm available to investigate this relationship in further detail.

  15. Patterns of DNA damage response in intracranial germ cell tumors versus glioblastomas reflect cell of origin rather than brain environment

    DEFF Research Database (Denmark)

    Bartkova, Jirina; Hoei-Hansen, Christina E; Krizova, Katerina

    2014-01-01

    The DNA damage response (DDR) machinery becomes commonly activated in response to oncogenes and during early stages of development of solid malignancies, with an exception of testicular germ cell tumors (TGCTs). The active DDR signaling evokes cell death or senescence but this anti-tumor barrier ...... checkpoints in intracranial tumorigenesis, with implications for the differential biological responses of diverse tumor types to endogenous stress as well as to genotoxic treatments such as ionizing radiation or chemotherapy....

  16. Evidence of viscerally-mediated cold-defence thermoeffector responses in man.

    Science.gov (United States)

    Morris, Nathan B; Filingeri, Davide; Halaki, Mark; Jay, Ollie

    2017-02-15

    Visceral thermoreceptors that modify thermoregulatory responses are widely accepted in animal but not human thermoregulation models. Recently, we have provided evidence of viscerally-mediated sweating alterations in humans during exercise brought about by warm and cool fluid ingestion. In the present study, we characterize the modification of shivering and whole-body thermal sensation during cold stress following the administration of a graded thermal stimuli delivered to the stomach via fluid ingestion at 52, 37, 22 and 7°C. Despite no differences in core and skin temperature, fluid ingestion at 52°C rapidly decreased shivering and sensations of cold compared to 37°C, whereas fluid ingestion at 22 and 7°C led to equivalent increases in these responses. Warm and cold fluid ingestion independently modifies cold defence thermoeffector responses, supporting the presence of visceral thermoreceptors in humans. However, the cold-defence thermoeffector response patterns differed from previously identified hot-defence thermoeffectors. Sudomotor activity is modified by both warm and cold fluid ingestion during heat stress, independently of differences in core and skin temperatures, suggesting independent viscerally-mediated modification of thermoeffectors. The present study aimed to determine whether visceral thermoreceptors modify shivering responses to cold stress. Ten males (mean ± SD: age 27 ± 5 years; height 1.73 ± 0.06 m, weight 78.4 ± 10.7 kg) underwent whole-body cooling via a water perfusion suit at 5°C, on four occasions, to induce a steady-state shivering response, at which point two aliquots of 1.5 ml kg -1 (SML) and 3.0 ml kg -1 (LRG), separated by 20 min, of water at 7, 22, 37 or 52°C were ingested. Rectal, mean skin and mean body temperature (T b ), electromyographic activity (EMG), metabolic rate (M) and whole-body thermal sensation on a visual analogue scale (WBTS) ranging from 0 mm (very cold) to 200 mm (very hot) were all

  17. Evaluation of cell responses toward adhesives with different photoinitiating systems.

    Science.gov (United States)

    Van Landuyt, Kirsten L; Krifka, Stephanie; Hiller, Karl-Anton; Bolay, Carola; Waha, Claudia; Van Meerbeek, Bart; Schmalz, Gottfried; Schweikl, Helmut

    2015-08-01

    The photoinitiator diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) is more reactive than a camphorquinone/amine (CQ) system, and TPO-based adhesives obtained a higher degree of conversion (DC) with fewer leached monomers. The hypothesis tested here is that a TPO-based adhesive is less toxic than a CQ-based adhesive. A CQ-based adhesive (SBU-CQ) (Scotchbond Universal, 3M ESPE) and its experimental counterpart with TPO (SBU-TPO) were tested for cytotoxicity in human pulp-derived cells (tHPC). Oxidative stress was analyzed by the generation of reactive oxygen species (ROS) and by the expression of antioxidant enzymes. A dentin barrier test (DBT) was used to evaluate cell viability in simulated clinical circumstances. Unpolymerized SBU-TPO was significantly more toxic than SBU-CQ after a 24h exposure, and TPO alone (EC50=0.06mM) was more cytotoxic than CQ (EC50=0.88mM), EDMAB (EC50=0.68mM) or CQ/EDMAB (EC50=0.50mM). Cultures preincubated with BSO (l-buthionine sulfoximine), an inhibitor of glutathione synthesis, indicated a minor role of glutathione in cytotoxic responses toward the adhesives. Although the generation of ROS was not detected, a differential expression of enzymatic antioxidants revealed that cells exposed to unpolymerized SBU-TPO or SBU-CQ are subject to oxidative stress. Polymerized SBU-TPO was more cytotoxic than SBU-CQ under specific experimental conditions only, but no cytotoxicity was detected in a DBT with a 200μm dentin barrier. Not only DC and monomer-release determine the biocompatibility of adhesives, but also the cytotoxicity of the (photo-)initiator should be taken into account. Addition of TPO rendered a universal adhesive more toxic compared to CQ; however, this effect could be annulled by a thin dentin barrier. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  18. Assessing the response to targeted therapies in renal cell carcinoma: technical insights and practical considerations.

    Science.gov (United States)

    Bex, Axel; Fournier, Laure; Lassau, Nathalie; Mulders, Peter; Nathan, Paul; Oyen, Wim J G; Powles, Thomas

    2014-04-01

    The introduction of targeted agents for the treatment of renal cell carcinoma (RCC) has resulted in new challenges for assessing response to therapy, and conventional response criteria using computed tomography (CT) are limited. It is widely recognised that targeted therapies may lead to significant necrosis without significant reduction in tumour size. In addition, the vascular effects of antiangiogenic therapy may occur long before there is any reduction in tumour size. To perform a systematic review of conventional and novel imaging methods for the assessment of response to targeted agents in RCC and to discuss their use from a clinical perspective. Relevant databases covering the period January 2006 to April 2013 were searched for studies reporting on the use of anatomic and functional imaging techniques to predict response to targeted therapy in RCC. Inclusion criteria were randomised trials, nonrandomised controlled studies, retrospective case series, and cohort studies. Reviews, animal and preclinical studies, case reports, and commentaries were excluded. A narrative synthesis of the evidence is presented. A total of 331 abstracts and 76 full-text articles were assessed; 34 studies met the inclusion criteria. Current methods of response assessment in RCC include anatomic methods--based on various criteria including Choi, size and attenuation CT, and morphology, attenuation, size, and structure--and functional techniques including dynamic contrast-enhanced (DCE) CT, DCE-magnetic resonance imaging, DCE-ultrasonography, positron emission tomography, and approaches utilising radiolabelled monoclonal antibodies. Functional imaging techniques are promising surrogate biomarkers of response in RCC and may be more appropriate than anatomic CT-based methods. By enabling quantification of tumour vascularisation, functional techniques can directly and rapidly detect the biologic effects of antiangiogenic therapies compared with the indirect detection of belated effects

  19. The B Cell Response to Foot-and-Mouth Disease Virus in Cattle following Sequential Vaccination with Multiple Serotypes.

    Science.gov (United States)

    Grant, Clare F J; Carr, B Veronica; Kotecha, Abhay; van den Born, Erwin; Stuart, David I; Hammond, John A; Charleston, Bryan

    2017-05-01

    Foot-and-mouth disease virus (FMDV) is a highly contagious viral disease. Antibodies are pivotal in providing protection against FMDV infection. Serological protection against one FMDV serotype does not confer interserotype protection. However, some historical data have shown that interserotype protection can be induced following sequential FMDV challenge with multiple FMDV serotypes. In this study, we have investigated the kinetics of the FMDV-specific antibody-secreting cell (ASC) response following homologous and heterologous inactivated FMDV vaccination regimes. We have demonstrated that the kinetics of the B cell response are similar for all four FMDV serotypes tested following a homologous FMDV vaccination regime. When a heterologous vaccination regime was used with the sequential inoculation of three different inactivated FMDV serotypes (O, A, and Asia1 serotypes) a B cell response to FMDV SAT1 and serotype C was induced. The studies also revealed that the local lymphoid tissue had detectable FMDV-specific ASCs in the absence of circulating FMDV-specific ASCs, indicating the presence of short-lived ASCs, a hallmark of a T-independent 2 (TI-2) antigenic response to inactivated FMDV capsid. IMPORTANCE We have demonstrated the development of intraserotype response following a sequential vaccination regime of four different FMDV serotypes. We have found indication of short-lived ASCs in the local lymphoid tissue, further evidence of a TI-2 response to FMDV. Copyright © 2017 American Society for Microbiology.

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

    Science.gov (United States)

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

    2012-04-01

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

  1. Role of autophagy in disease resistance and hypersensitive response-associated cell death

    DEFF Research Database (Denmark)

    Hofius, Daniel; Munch, David; Bressendorff, Simon

    2011-01-01

    Ancient autophagy pathways are emerging as key defense modules in host eukaryotic cells against microbial pathogens. Apart from actively eliminating intracellular intruders, autophagy is also responsible for cell survival, for example by reducing the deleterious effects of endoplasmic reticulum...

  2. L-Amino Acids Elicit Diverse Response Patterns in Taste Sensory Cells: A Role for Multiple Receptors

    Science.gov (United States)

    Pal Choudhuri, Shreoshi; Delay, Rona J.; Delay, Eugene R.

    2015-01-01

    Umami, the fifth basic taste, is elicited by the L-amino acid, glutamate. A unique characteristic of umami taste is the response potentiation by 5’ ribonucleotide monophosphates, which are also capable of eliciting an umami taste. Initial reports using human embryonic kidney (HEK) cells suggested that there is one broadly tuned receptor heterodimer, T1r1+T1r3, which detects L-glutamate and all other L-amino acids. However, there is growing evidence that multiple receptors detect glutamate in the oral cavity. While much is understood about glutamate transduction, the mechanisms for detecting the tastes of other L-amino acids are less well understood. We used calcium imaging of isolated taste sensory cells and taste cell clusters from the circumvallate and foliate papillae of C57BL/6J and T1r3 knockout mice to determine if other receptors might also be involved in detection of L-amino acids. Ratiometric imaging with Fura-2 was used to study calcium responses to monopotassium L-glutamate, L-serine, L-arginine, and L-glutamine, with and without inosine 5’ monophosphate (IMP). The results of these experiments showed that the response patterns elicited by L-amino acids varied significantly across taste sensory cells. L-amino acids other than glutamate also elicited synergistic responses in a subset of taste sensory cells. Along with its role in synergism, IMP alone elicited a response in a large number of taste sensory cells. Our data indicate that synergistic and non-synergistic responses to L-amino acids and IMP are mediated by multiple receptors or possibly a receptor complex. PMID:26110622

  3. Response competition and response inhibition during different choice-discrimination tasks: evidence from ERP measured inside MRI scanner.

    Science.gov (United States)

    Gonzalez-Rosa, Javier J; Inuggi, Alberto; Blasi, Valeria; Cursi, Marco; Annovazzi, Pietro; Comi, Giancarlo; Falini, Andrea; Leocani, Letizia

    2013-07-01

    We investigated the neural correlates underlying response inhibition and conflict detection processes using ERPs and source localization analyses simultaneously acquired during fMRI scanning. ERPs were elicited by a simple reaction time task (SRT), a Go/NoGo task, and a Stroop-like task (CST). The cognitive conflict was thus manipulated in order to probe the degree to which information processing is shared across cognitive systems. We proposed to dissociate inhibition and interference conflict effects on brain activity by using identical Stroop-like congruent/incongruent stimuli in all three task contexts and while varying the response required. NoGo-incongruent trials showed a larger N2 and enhanced activations of rostral anterior cingulate cortex (ACC) and pre-supplementary motor area, whereas Go-congruent trials showed a larger P3 and increased parietal activations. Congruent and incongruent conditions of the CST task also elicited similar N2, P3 and late negativity (LN) ERPs, though CST-incongruent trials revealed a larger LN and enhanced prefrontal and ACC activations. Considering the stimulus probability and experimental manipulation of our study, current findings suggest that NoGo N2 and frontal NoGo P3 appear to be more associated to response inhibition rather than a specific conflict monitoring, whereas occipito-parietal P3 of Go and CST conditions may be more linked to a planned response competition between the prepared and required response. LN, however, appears to be related to higher level conflict monitoring associated with response choice-discrimination but not when the presence of cognitive conflict is associated with response inhibition. Copyright © 2013. Published by Elsevier B.V.

  4. No evidence for dualism in function and receptors: PD-L2/B7-DC is an inhibitory regulator of human T cell activation.

    Science.gov (United States)

    Pfistershammer, Katharina; Klauser, Christoph; Pickl, Winfried F; Stöckl, Johannes; Leitner, Judith; Zlabinger, Gerhard; Majdic, Otto; Steinberger, Peter

    2006-05-01

    The B7 family member programmed-death-1-ligand 2 (PD-L2/B7-DC) is a ligand for programmed-death-receptor 1 (PD-1), a receptor involved in negative regulation of T cell activation. Several independent studies have reported that PD-L2, however, can also potently costimulate murine T cells via an additional yet unidentified receptor. In this study, we evaluated the contribution of PD-L2 to the activation of human T cells using a novel system of engineered T cell stimulators that expresses membrane-bound anti-CD3 antibodies. Analyzing early activation markers, cytokine production and proliferation, we found PD-L2 to consistently inhibit T cell activation. PD-L2 inhibition affected CD4+ and CD8+ T cells and was not abrogated by costimulation via CD28. Blocking PD-1 reverted the inhibitory effect of PD-L2, demonstrating involvement of this pathway. In human T cells, we found no evidence for any of the costimulatory effects described for PD-L2 in murine systems. In line with our functional data that do not point to stimulatory PD-L2-ligands, we show that binding of PD-L2-immunoglobulin to activated human T cells is abrogated by PD-1 antibodies. Our results demonstrate that PD-L2 negatively regulates human T cell activation and thus might be a candidate molecule for immunotherapeutic approaches aimed to attenuate pathological immune responses.

  5. Cytogenetic dose-response and adaptive response in cells of ungulate species exposed to ionizing radiation

    International Nuclear Information System (INIS)

    Ulsh, B.A.; Miller, S.M.; Mallory, F.F.; Mitchel, R.E.J.; Morrison, D.P.; Boreham, D.R.

    2004-01-01

    In the studies reported here, the micronucleus assay, a common cytogenetic technique, was used to examine the dose-responses in fibroblasts from three ungulate species (white-tailed deer, woodland caribou, and Indian muntjac) exposed to high doses of ionizing radiation (1-4 Gy of 60 Co gamma radiation). This assay was also used to examine the effects of exposure to low doses (1-100 mGy) typical of what these species experience in a year from natural and anthropogenic environmental sources. An adaptive response, defined as the induction of resistance to a stressor by a prior exposure to a small 'adapting' stress, was observed after exposure to low doses. This work indicates that very small doses are protective for the endpoint examined. The same level of protection was seen at all adapting doses, including 1 radiation track per cell, the lowest possible cellular dose. These results are consistent with other studies in a wide variety of organisms that demonstrate a protective effect of low doses at both cellular and whole-organism levels. This implies that environmental regulations predicated on the idea that even the smallest dose of radiation carries a quantifiable risk of direct adverse consequences to the exposed organism require further examination. Cytogenetic assays provide affordable and feasible biological effects-based alternatives that are more biologically relevant than traditional contaminant concentration-based radioecological risk assessment

  6. ZFAT plays critical roles in peripheral T cell homeostasis and its T cell receptor-mediated response

    International Nuclear Information System (INIS)

    Doi, Keiko; Fujimoto, Takahiro; Okamura, Tadashi; Ogawa, Masahiro; Tanaka, Yoko; Mototani, Yasumasa; Goto, Motohito; Ota, Takeharu; Matsuzaki, Hiroshi; Kuroki, Masahide; Tsunoda, Toshiyuki; Sasazuki, Takehiko; Shirasawa, Senji

    2012-01-01

    Highlights: ► We generated Cd4-Cre-mediated T cell-specific Zfat-deficient mice. ► Zfat-deficiency leads to reduction in the number of the peripheral T cells. ► Impaired T cell receptor-mediated response in Zfat-deficient peripheral T cells. ► Decreased expression of IL-7Rα, IL-2Rα and IL-2 in Zfat-deficient peripheral T cells. ► Zfat plays critical roles in peripheral T cell homeostasis. -- Abstract: ZFAT, originally identified as a candidate susceptibility gene for autoimmune thyroid disease, has been reported to be involved in apoptosis, development and primitive hematopoiesis. Zfat is highly expressed in T- and B-cells in the lymphoid tissues, however, its physiological function in the immune system remains totally unknown. Here, we generated the T cell-specific Zfat-deficient mice and demonstrated that Zfat-deficiency leads to a remarkable reduction in the number of the peripheral T cells. Intriguingly, a reduced expression of IL-7Rα and the impaired responsiveness to IL-7 for the survival were observed in the Zfat-deficient T cells. Furthermore, a severe defect in proliferation and increased apoptosis in the Zfat-deficient T cells following T cell receptor (TCR) stimulation was observed with a reduced IL-2Rα expression as well as a reduced IL-2 production. Thus, our findings reveal that Zfat is a critical regulator in peripheral T cell homeostasis and its TCR-mediated response.

  7. Antibody and B cell responses to Plasmodium sporozoites

    Directory of Open Access Journals (Sweden)

    Johanna N Dups

    2014-11-01

    Full Text Available Antibodies are capable of blocking infection of the liver by Plasmodium sporozoites. Accordingly the induction of anti-sporozoite antibodies is a major aim of various vaccine approaches to malaria. In recent years our knowledge of the specificity and quantities of antibodies required for protection has been greatly expanded by clinical trials of various whole sporozoite and subunit vaccines. Moreover, the development of humanized mouse models and transgenic parasites have also aided our ability to assess the specificity of antibodies and their ability to block infection. Nonetheless, considerable gaps remain in our knowledge - in particular in understanding what antigens are recognized by infection blocking antibodies and in knowing how we can induce robust, long-lived antibody responses. Maintaining high levels of circulating antibodies is likely to be of primary importance, as antibodies must block infection in the short time it takes for sporozoites to reach the liver from the skin. It is clear that a better understanding of the development of protective B cell-mediated immunity will aid the development and refinement of malaria vaccines.

  8. Impaired antibody response causes persistence of prototypic T cell-contained virus.

    Directory of Open Access Journals (Sweden)

    Andreas Bergthaler

    2009-04-01

    Full Text Available CD8 T cells are recognized key players in control of persistent virus infections, but increasing evidence suggests that assistance from other immune mediators is also needed. Here, we investigated whether specific antibody responses contribute to control of lymphocytic choriomeningitis virus (LCMV, a prototypic mouse model of systemic persistent infection. Mice expressing transgenic B cell receptors of LCMV-unrelated specificity, and mice unable to produce soluble immunoglobulin M (IgM exhibited protracted viremia or failed to resolve LCMV. Virus control depended on immunoglobulin class switch, but neither on complement cascades nor on Fc receptor gamma chain or Fc gamma receptor IIB. Cessation of viremia concurred with the emergence of viral envelope-specific antibodies, rather than with neutralizing serum activity, and even early nonneutralizing IgM impeded viral persistence. This important role for virus-specific antibodies may be similarly underappreciated in other primarily T cell-controlled infections such as HIV and hepatitis C virus, and we suggest this contribution of antibodies be given consideration in future strategies for vaccination and immunotherapy.

  9. SV40-transformed human fibroblasts: evidence for cellular aging in pre-crisis cells.

    Science.gov (United States)

    Stein, G H

    1985-10-01

    Pre-crisis SV40-transformed human diploid fibroblast (HDF) cultures have a finite proliferative lifespan, but they do not enter a viable senescent state at end of lifespan. Little is known about either the mechanism for this finite lifespan in SV40-transformed HDF or its relationship to finite lifespan in normal HDF. Recently we proposed that in normal HDF the phenomena of finite lifespan and arrest in a viable senescent state depend on two separate processes: 1) an age-related decrease in the ability of the cells to recognize or respond to serum and/or other mitogens such that the cells become functionally mitogen-deprived at the end of lifespan; and 2) the ability of the cells to enter a viable, G1-arrested state whenever they experience mitogen deprivation. In this paper, data are presented that suggest that pre-crisis SV40-transformed HDF retain the first process described above, but lack the second process. It is shown that SV40-transformed HDF have a progressively decreasing ability to respond to serum as they age, but they continue to traverse the cell cycle at the end of lifespan. Concomitantly, the rate of cell death increases steadily toward the end of lifespan, thereby causing the total population to cease growing and ultimately to decline. Previous studies have shown that when SV40-transformed HDF are environmentally serum deprived, they likewise exhibit continued cell cycle traverse coupled with increased cell death. Thus, these results support the hypothesis that pre-crisis SV40-transformed HDF still undergo the same aging process as do normal HDF, but they end their lifespan in crisis rather than in the normal G1-arrested senescent state because they have lost their ability to enter a viable, G1-arrested state in response to mitogen deprivation.

  10. SAP expression in invariant NKT cells is required for cognate help to support B-cell responses.

    Science.gov (United States)

    Detre, Cynthia; Keszei, Marton; Garrido-Mesa, Natividad; Kis-Toth, Katalin; Castro, Wilson; Agyemang, Amma F; Veerapen, Natacha; Besra, Gurdyal S; Carroll, Michael C; Tsokos, George C; Wang, Ninghai; Leadbetter, Elizabeth A; Terhorst, Cox

    2012-07-05

    One of the manifestations of X-linked lymphoproliferative disease (XLP) is progressive agammaglobulinemia, caused by the absence of a functional signaling lymphocyte activation molecule (SLAM)-associated protein (SAP) in T, invariant natural killer T (NKT) cells and NK cells. Here we report that α-galactosylceramide (αGalCer) activated NKT cells positively regulate antibody responses to haptenated protein antigens at multiple checkpoints, including germinal center formation and affinity maturation. Whereas NKT cell-dependent B cell responses were absent in SAP(-/-).B6 mice that completely lack NKT cells, the small number of SAP-deficient NKT cells in SAP(-/-).BALB/c mice adjuvated antibody production, but not the germinal center reaction. To test the hypothesis that SAP-deficient NKT cells can facilitate humoral immunity, SAP was deleted after development in SAP(fl/fl).tgCreERT2.B6 mice. We find that NKT cell intrinsic expression of SAP is dispensable for noncognate helper functions, but is critical for providing cognate help to antigen-specific B cells. These results demonstrate that SLAM-family receptor-regulated cell-cell interactions are not limited to T-B cell conjugates. We conclude that in the absence of SAP, several routes of NKT cell-mediated antibody production are still accessible. The latter suggests that residual NKT cells in XLP patients might contribute to variations in dysgammaglobulinemia.

  11. The influence of Listeria monocytogenes cells on the primary immunologic response in irradiated mice

    International Nuclear Information System (INIS)

    Borowski, J.; Jokoniuk, P.

    1977-01-01

    The influence of killed Listeria monocytogenes cells on the primary immunologic response in mice irradiated with 300 or 500 R was studied. The immunologic response of the mice to sheep red blood cells used as antigen was assessed at the cellular level (by counting PFC) and humoral level. Injection of killed Listeria monocytogenes cells before irradiation of the mice diminished the immunosuppressive effect of roentgen radiation. Injection of the cells after irradiation accelerated regeneration of immunologic reactivity in the irradiated mice. (author)

  12. The cell wall and endoplasmic reticulum stress responses are coordinately regulated in Saccharomyces cerevisiae

    OpenAIRE

    Krysan, Damian J

    2009-01-01

    The unfolded protein response (UPR) is an intracellular signaling pathway that regulates the cellular response to the accumulation of misfolded proteins in eukaryotes. Our group has demonstrated that cell wall stress activates UPR in yeast through signals transmitted by the cell wall integrity (CWI) mitogen-activated protein (MAP) kinase cascade. The UPR is required to maintain cell wall integrity; mutants lacking a functional UPR have defects in cell wall biosynthesis and are hypersensitive ...

  13. Maturation of the human fetal startle response: Evidence for sex-specific maturation of the human fetus1

    Science.gov (United States)

    Buss, Claudia; Davis, Elysia Poggi; Class, Quetzal A.; Gierczak, Matt; Pattillo, Carol; Glynn, Laura M.; Sandman, Curt A.

    2009-01-01

    Despite the evidence for early fetal experience exerting programming influences on later neurological development and health risk, very few prospective studies of human fetal behavior have been reported. In a prospective longitudinal study, fetal nervous system maturation was serially assessed by monitoring fetal heart rate (FHR) responses to vibroacoustic stimulation (VAS) in 191 maternal/fetal dyads. Responses were not detected at 26 weeks gestational age (GA). Sex-specific, age-characteristic changes in the FHR response to VAS were observed by 31 weeks’ GA. Males showed larger responses and continued to exhibit maturational changes until 37 weeks’ GA, females however, presented with a mature FHR startle response by 31 weeks’ GA. The results indicate that there are different rates of maturation in the male and female fetus that may have implications for sex-specific programming influences. PMID:19726143

  14. Maturation of the human fetal startle response: evidence for sex-specific maturation of the human fetus.

    Science.gov (United States)

    Buss, Claudia; Davis, Elysia Poggi; Class, Quetzal A; Gierczak, Matt; Pattillo, Carol; Glynn, Laura M; Sandman, Curt A

    2009-10-01

    Despite the evidence for early fetal experience exerting programming influences on later neurological development and health risk, very few prospective studies of human fetal behavior have been reported. In a prospective longitudinal study, fetal nervous system maturation was serially assessed by monitoring fetal heart rate (FHR) responses to vibroacoustic stimulation (VAS) in 191 maternal/fetal dyads. Responses were not detected at 26 weeks gestational age (GA). Sex-specific, age-characteristic changes in the FHR response to VAS were observed by 31 weeks' GA. Males showed larger responses and continued to exhibit maturational changes until 37 weeks' GA, females however, presented with a mature FHR startle response by 31 weeks' GA. The results indicate that there are different rates of maturation in the male and female fetuses that may have implications for sex-specific programming influences.

  15. Circulating CD4+CXCR5+ T cells contribute to proinflammatory responses in multiple ways in coronary artery disease.

    Science.gov (United States)

    Ding, Ru; Gao, Wenwu; He, Zhiqing; Wu, Feng; Chu, Yang; Wu, Jie; Ma, Lan; Liang, Chun

    2017-11-01

    Coronary artery disease (CAD) is a common subtype of cardiovascular disease. The major contributing event is atherosclerosis, which is a progressive inflammatory condition resulting in the thickening of the arterial wall and the formation of atheromatous plaques. Recent evidence suggests that circulating CD4 + CXCR5 + T cells can contribute to inflammatory reactions. In this study, the frequency, phenotype, and function of circulating CD4 + CXCR5 + T cells in CAD patients were examined. Data showed that circulating CD4 + CXCR5 + T cells in CAD patients were enriched with a PD-1 + CCR7 - subset, which was previously identified as the most potent in B cell help. The CD4 + CXCR5 + T cells in CAD patients also secreted significantly higher levels of IFN-γ, IL-17A, and IL-21 than those from healthy controls. Depleting the PD-1 + population significantly reduced the cytokine secretion. Interestingly, the CD4 + CXCR5 + PD-1 - T cells significantly upregulated PD-1 following anti-CD3/CD28 or SEB stimulation. CD4 + CXCR5 + T cells from CAD patients also demonstrated more potent capacity to stimulate B cell inflammation than those from healthy individuals. The phosphorylation of STAT1 and STAT3 were significantly higher in B cells incubated with CD4 + CXCR5 + T cells from CAD than controls. The IL-6 and IFN-γ expression were also significantly higher in B cells incubated with CD4 + CXCR5 + T cells from CAD. Together, this study demonstrated that CAD patients presented a highly activated CD4 + CXCR5 + T cell subset that could contribute to proinflammatory responses in multiple ways. The possibility of using CD4 + CXCR5 + T cells as a therapeutic target should therefore be examined in CAD patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Evidence that glutamate mediates axon-to-Schwann cell signaling in the squid.

    Science.gov (United States)

    Lieberman, E M; Abbott, N J; Hassan, S

    1989-01-01

    High-frequency stimulation (100 Hz) of isolated giant axons of the small squid Alloteuthis subulata and the large squid Loligo forbesi caused the periaxonal Schwann cell resting potential (Em = -40 mV) to hyperpolarize up to 11 mV in direct proportion to train duration and action potential amplitude. In both species, the Schwann cell also hyperpolarized up to 17 mV with the application of L-glutamate (10(-9) to 10(-6) M), in a dose-dependent manner. By contrast, in the presence of 10(-8) M d-tubocurarine (d-TC) to block the cholinergic component of the Schwann cell response, Schwann cells depolarized 8-9 mV during electrical stimulation of the axon or application of L-glutamate. In the presence of 10(-5) M 2-amino-4-phosphonobutyrate (2-APB), the hyperpolarization to glutamate and to axon stimulation was blocked, whereas the cholinergic (carbachol-induced) hyperpolarization was unaffected. In experiments with Alloteuthis, L-aspartate (10(-7) M) also caused a Schwann cell hyperpolarization, but this was not blocked by 2-APB. In tests with glutamate receptor agonists and antagonists, quisqualate (10(-5) M) produced a hyperpolarization blocked by 10(-4) M L-glutamic acid diethylester (GDEE), which also blocked the response to axonal stimulation. Kainic acid (10(-4) M) also caused a hyperpolarization, but n-methyl-D-aspartate (NMDA; 10(-4) M), ibotenate (10(-5) M), alpha-amino-3-hydroxy-5-methyl-isoxazole proprionate (AMPA; (10(-4) M), and isethionate (10(-5) M) had no effect.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Metastatic non-small cell lung cancer Current treatment based on evidence (ONCOL Group)

    International Nuclear Information System (INIS)

    Castro, Carlos; Cardona, Andres Felipe; Reveiz, Ludovic; Serrano, Silvia Juliana; Carranza, Hernan; Vargas, Carlos Alberto; Reguart, Noemi; Campo, Felipe; Ospina, Edgar Guillermo; Sanchez, Oswaldo; Torres, Diana; Otero, Jorge Miguel

    2010-01-01

    to perform a review of evidence about the treatment of non-small cell lung cancer (NSCLC). Source of data: the information was obtained from searches conducted in Medline, CCTR, Biosis, Embase, Lilacs and CINHAL. We also collected the most representative references presented during the last five years at Asco, ESMO and IASLC. Data extraction: data were extracted by associate members to the ONCOL Group. The collection of information did not follow a uniform strategy. Results of data synthesis: therapy for NSCLC can prolong survival and improve quality of life, but the majority of advanced stage patients dies due to disease progression within 2 years, meaning that there is room for improvement. The standard chemotherapy for NSCLC involves one of a number of platinum-based doublets that have been shown to improve survival when compared with single agents or best supportive care. These doublets are generally comparable in terms of efficacy, differing primarily in their toxicity profiles. However, encouraging new options may be approaching, including therapies targeted to specific patient subpopulations, and the use of combinations of current and new drugs to produce synergistic effects. This review present a detailed analysis of current evidence regarding the treatment of NSCLC based on a representative case series. This review didn't conduct a systematic evaluation of the evidence. Conclusion: medical therapy for NSCLC produces positive changes in main outcomes, including quality of life

  18. Balancing the dual responsibilities of business unit controllers: field and survey evidence

    NARCIS (Netherlands)

    Maas, V.S.; Matejka, M.

    2009-01-01

    We examine how business unit (BU) controllers balance their dual roles of providing information for both local decision-making (local responsibility) and corporate control (functional responsibility). The existing literature suggests that organizations can improve the quality of financial reporting

  19. Intracellular proteins produced by mammalian cells in response to environmental stress

    Science.gov (United States)

    Goochee, Charles F.; Passini, Cheryl A.

    1988-01-01

    The nature of the response of mammalian cells to environmental stress is examined by reviewing results of studies where cultured mouse L cells and baby hamster kidney cells were exposed to heat shock and the synthesis of heat-shock proteins and stress-response proteins (including HSP70, HSC70, HSP90, ubiquitin, and GRP70) in stressed and unstressed cells was evaluated using 2D-PAGE. The intracellular roles of the individual stress response proteins are discussed together with the regulation of the stress response system.

  20. [Prediction of the molecular response to pertubations from single cell measurements].

    Science.gov (United States)

    Remacle, Françoise; Levine, Raphael D

    2014-12-01

    The response of protein signalization networks to perturbations is analysed from single cell measurements. This experimental approach allows characterizing the fluctuations in protein expression levels from cell to cell. The analysis is based on an information theoretic approach grounded in thermodynamics leading to a quantitative version of Le Chatelier principle which allows to predict the molecular response. Two systems are investigated: human macrophages subjected to lipopolysaccharide challenge, analogous to the immune response against Gram-negative bacteria and the response of the proteins involved in the mTOR signalizing network of GBM cancer cells to changes in partial oxygen pressure. © 2014 médecine/sciences – Inserm.

  1. Lowering T Cell Activation Thresholds and Deregulating Homeostasis to Facilitate Immunotherapeutic Responses to Treat Prostate Cancer

    National Research Council Canada - National Science Library

    Kwon, Eugene D

    2006-01-01

    ... to develop immune-based therapies for prostate cancer Hence, relatively straightforward manipulations that induce specific T cell responses against prostate tumors or epithelial tissues, especially...

  2. Osteoblast cell response to surface-modified carbon nanotubes

    International Nuclear Information System (INIS)

    Zhang Faming; Weidmann, Arne; Nebe, J. Barbara; Burkel, Eberhard

    2012-01-01

    In order to investigate the interaction of cells with modified multi-walled carbon nanotubes (MWCNTs) for their potential biomedical applications, the MWCNTs were chemically modified with carboxylic acid groups (–COOH), polyvinyl alcohol (PVA) polymer and biomimetic apatite on their surfaces. Additionally, human osteoblast MG-63 cells were cultured in the presence of the surface-modified MWCNTs. The metabolic activities of osteoblastic cells, cell proliferation properties, as well as cell morphology were studied. The surface modification of MWCNTs with biomimetic apatite exhibited a significant increase in the cell viability of osteoblasts, up to 67.23%. In the proliferation phases, there were many more cells in the biomimetic apatite-modified MWCNT samples than in the MWCNTs–COOH. There were no obvious changes in cell morphology in osteoblastic MG-63 cells cultured in the presence of these chemically-modified MWCNTs. The surface modification of MWCNTs with apatite achieves an effective enhancement of their biocompatibility.

  3. Preliminary evidence for genetic overlap between body mass index and striatal reward response.

    Science.gov (United States)

    Lancaster, T M; Ihssen, I; Brindley, L M; Linden, D E

    2018-01-10

    The reward-processing network is implicated in the aetiology of obesity. Several lines of evidence suggest obesity-linked genetic risk loci (such as DRD2 and FTO) may influence individual variation in body mass index (BMI) through neuropsychological processes reflected in alterations in activation of the striatum during reward processing. However, no study has tested the broader hypotheses that (a) the relationship between BMI and reward-related brain activation (measured through the blood oxygenation-dependent (BOLD) signal) may be observed in a large population study and (b) the overall genetic architecture of these phenotypes overlap, an assumption critical for the progression of imaging genetic studies in obesity research. Using data from the Human Connectome Project (N = 1055 healthy, young individuals: average BMI = 26.4), we first establish a phenotypic relationship between BMI and ventral striatal (VS) BOLD during the processing of rewarding (monetary) stimuli (β = 0.44, P = 0.013), accounting for potential confounds. BMI and VS BOLD were both significantly influenced by additive genetic factors (H2r = 0.57; 0.12, respectively). Further decomposition of this variance suggested that the relationship was driven by shared genetic (ρ g  = 0.47, P = 0.011), but not environmental (ρ E  = -0.07, P = 0.29) factors. To validate the assumption of genetic pleiotropy between BMI and VS BOLD, we further show that polygenic risk for higher BMI is also associated with increased VS BOLD response to appetitive stimuli (calorically high food images), in an independent sample (N = 81; P FWE-ROI  < 0.005). Together, these observations suggest that the genetic factors link risk to obesity to alterations within key nodes of the brain's reward circuity. These observations provide a basis for future work exploring the mechanistic role of genetic loci that confer risk for obesity using the imaging genetics approach.

  4. ARTEMIS stabilizes the genome and modulates proliferative responses in multipotent mesenchymal cells

    Directory of Open Access Journals (Sweden)

    Tompkins Kathleen

    2010-10-01

    Full Text Available Abstract Background Unrepaired DNA double-stranded breaks (DSBs cause chromosomal rearrangements, loss of genetic information, neoplastic transformation or cell death. The nonhomologous end joining (NHEJ pathway, catalyzing sequence-independent direct rejoining of DSBs, is a crucial mechanism for repairing both stochastically occurring and developmentally programmed DSBs. In lymphocytes, NHEJ is critical for both development and genome stability. NHEJ defects lead to severe combined immunodeficiency (SCID and lymphoid cancer predisposition in both mice and humans. While NHEJ has been thoroughly investigated in lymphocytes, the importance of NHEJ in other cell types, especially with regard to tumor suppression, is less well documented. We previously reported evidence that the NHEJ pathway functions to suppress a range of nonlymphoid tumor types, including various classes of sarcomas, by unknown mechanisms. Results Here we investigate roles for the NHEJ factor ARTEMIS in multipotent mesenchymal stem/progenitor cells (MSCs, as putative sarcomagenic cells of origin. We demonstrate a key role for ARTEMIS in sarcoma suppression in a sensitized mouse tumor model. In this context, we found that ARTEMIS deficiency led to chromosomal damage but, paradoxically, enhanced resistance and proliferative potential in primary MSCs subjected to various stresses. Gene expression analysis revealed abnormally regulated stress response, cell proliferation, and signal transduction pathways in ARTEMIS-defective MSCs. Finally, we identified candidate regulatory genes that may, in part, mediate a stress-resistant, hyperproliferative phenotype in preneoplastic ARTEMIS-deficient MSCs. Conclusions Our discoveries suggest that Art prevents genome damage and restrains proliferation in MSCs exposed to various stress stimuli. We propose that deficiency leads to a preneoplastic state in primary MSCs and is associated with aberrant proliferative control and cellular stress

  5. Enthesis fibrocartilage cells originate from a population of Hedgehog-responsive cells modulated by the loading environment.

    Science.gov (United States)

    Schwartz, Andrea G; Long, Fanxin; Thomopoulos, Stavros

    2015-01-01

    Tendon attaches to bone across a specialized tissue called the enthesis. This tissue modulates the transfer of muscle forces between two materials, i.e. tendon and bone, with vastly different mechanical properties. The enthesis for many tendons consists of a mineralized graded fibrocartilage that develops postnatally, concurrent with epiphyseal mineralization. Although it is well described that the mineralization and development of functional maturity requires muscle loading, the biological factors that modulate enthesis development are poorly understood. By genetically demarcating cells expressing Gli1 in response to Hedgehog (Hh) signaling, we discovered a unique population of Hh-responsive cells in the developing murine enthesis that were distinct from tendon fibroblasts and epiphyseal chondrocytes. Lineage-tracing experiments revealed that the Gli1 lineage cells that originate in utero eventually populate the entire mature enthesis. Muscle paralysis increased the number of Hh-responsive cells in the enthesis, demonstrating that responsiveness to Hh is modulated in part by muscle loading. Ablation of the Hh-responsive cells during the first week of postnatal development resulted in a loss of mineralized fibrocartilage, with very little tissue remodeling 5 weeks after cell ablation. Conditional deletion of smoothened, a molecule necessary for responsiveness to Ihh, from the developing tendon and enthesis altered the differentiation of enthesis progenitor cells, resulting in significantly reduced fibrocartilage mineralization and decreased biomechanical function. Taken together, these results demonstrate that Hh signaling within developing enthesis fibrocartilage cells is required for enthesis formation. © 2015. Published by The Company of Biologists Ltd.

  6. Vaccine Targeting of Subdominant CD8+ T Cell Epitopes Increases the Breadth of the T Cell Response upon Viral Challenge, but May Impair Immediate Virus Control

    DEFF Research Database (Denmark)

    Steffensen, Maria A; Pedersen, Louise Holm; Jahn, Marie Louise

    2016-01-01

    As a result of the difficulties in making efficient vaccines against genetically unstable viruses such as HIV, it has been suggested that future vaccines should preferentially target subdominant epitopes, the idea being that this should allow a greater breadth of the induced T cell response and, ...... a limitation of our model, but clearly our findings underscore the importance of carefully weighing the pros and cons of changes in epitope targeting before any implementation.......As a result of the difficulties in making efficient vaccines against genetically unstable viruses such as HIV, it has been suggested that future vaccines should preferentially target subdominant epitopes, the idea being that this should allow a greater breadth of the induced T cell response and......, hence, a greater efficiency in controlling escape variants. However, to our knowledge the evidence supporting this concept is limited at best. To improve upon this, we used the murine lymphocytic choriomeningitis virus model and adenoviral vectors to compare a vaccine expressing unmodified Ag...

  7. Unconventional Pro-inflammatory CD4+ T Cell Response in B Cell-Deficient Mice Infected with Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Melisa Gorosito Serrán

    2017-11-01

    Full Text Available Chagas disease, caused by the parasite Trypanosoma cruzi, is endemic in Latin America but has become a global public health concern by migration of infected people. It has been reported that parasite persistence as well as the intensity of the inflammatory immune response are determinants of the clinical manifestations of the disease. Even though inflammation is indispensable for host defense, when deregulated, it can contribute to tissue injury and organ dysfunction. Here, we report the importance of B cells in conditioning T cell response in T. cruzi infection. Mice deficient in mature B cells (muMT mice infected with T. cruzi exhibited an increase in plasma TNF concentration, TNF-producing CD4+ T cells, and mortality. The increase in TNF-producing CD4+ T cells was accompanied by a reduction in IFNγ+CD4+ T cells and a decrease of the frequency of regulatory Foxp3+, IL-10+, and IL17+CD4+ T cells populations. The CD4+ T cell population activated by T. cruzi infection, in absence of mature B cells, had a high frequency of Ly6C+ cells and showed a lower expression of inhibitory molecules such as CTLA-4, PD-1, and LAG3. CD4+ T cells from infected muMT mice presented a high frequency of CD62LhiCD44− cells, which is commonly associated with a naïve phenotype. Through transfer experiments we demonstrated that CD4+ T cells from infected muMT mice were able to condition the CD4+ T cells response from infected wild-type mice. Interestingly, using Blimp-flox/flox-CD23icre mice we observed that in absence of plasmablast/plasma cell T. cruzi-infected mice exhibited a higher number of TNF-producing CD4+ T cells. Our results showed that the absence of B cells during T. cruzi infection affected the T cell response at different levels and generated a favorable scenario for unconventional activation of CD4+ T cell leading to an uncontrolled effector response and inflammation. The product of B cell differentiation, the plasmablast/plasma cells, could be able

  8. Is pupillary response a reliable index of word recognition? Evidence from a delayed lexical decision task.

    Science.gov (United States)

    Haro, Juan; Guasch, Marc; Vallès, Blanca; Ferré, Pilar

    2017-10-01

    Previous word recognition studies have shown that the pupillary response is sensitive to a word's frequency. However, such a pupillary effect may be due to the process of executing a response, instead of being an index of word processing. With the aim of exploring this possibility, we recorded the pupillary responses in two experiments involving a lexical decision task (LDT). In the first experiment, participants completed a standard LDT, whereas in the second they performed a delayed LDT. The delay in the response allowed us to compare pupil dilations with and without the response execution component. The results showed that pupillary response was modulated by word frequency in both the standard and the delayed LDT. This finding supports the reliability of using pupillometry for word recognition research. Importantly, our results also suggest that tasks that do not require a response during pupil recording lead to clearer and stronger effects.

  9. Toward a method of collaborative, evidence-based response to desertification

    Science.gov (United States)

    Overgeneralized narratives about how desertified ecosystems will respond to restoration actions may result in wasted resources, missed opportunities, or accelerated degradation. Evidence-based collaborative adaptive management (CAM) could solve this problem by providing site-specific information tha...

  10. Are Breast Tumor Stem Cells Responsible for Metastasis and Angiogenesis?

    National Research Council Canada - National Science Library

    Pan, Quintin

    2005-01-01

    .... The current dogma of metastasis is that most primary tumor cells have low metastatic potential, but rare cells, less than one in ten million, within large primary tumors acquire metastatic capacity...

  11. Artifactual voltage response recorded from hair cells with patch-clamp amplifiers.

    Science.gov (United States)

    Masetto, S; Weng, T; Valli, P; Correia, M J

    1999-06-23

    Patch-clamp amplifiers (PCAs) are commonly used to characterize voltage- and current-clamp responses in the same cell. However, the cell membrane voltage response can be severely distorted by PCAs working in the current-clamp mode. Here we compare the voltage response of pigeon semicircular canal hair cells in situ, recorded with two different PCAs, and with a classic microelectrode bridge amplifier (BA). We found that the voltage response of hair cells recorded with PCAs differed significantly from that recorded with the BA. The true hair cell membrane voltage response to positive current steps was characterized by a strongly damped oscillation, whose frequency and duration depended on hair cell location in the sensory crista ampullaris.

  12. A response to: "NIST experts urge caution in use of courtroom evidence presentation method"

    OpenAIRE

    Morrison, Geoffrey Stewart

    2017-01-01

    A press release from the National Institute of Standards and Technology (NIST)could potentially impede progress toward improving the analysis of forensic evidence and the presentation of forensic analysis results in courts in the United States and around the world. "NIST experts urge caution in use of courtroom evidence presentation method" was released on October 12, 2017, and was picked up by the phys.org news service. It argues that, except in exceptional cases, the results of forensic ana...

  13. Synergy among rat T cells in the proliferative response to alloantigen

    International Nuclear Information System (INIS)

    Wright, P.W.; Loop, S.M.; Bernstein, I.D.

    1979-01-01

    A synergistic interaction in the proliferative response to alloantigen is described for mixtures of rat thymus and lymph node cells. The optimal conditions for synergy are quantitatively defined. Regression analysis of the slope of the dose-response curve has been utilized to estimate the degree of interaction in thymus--lymph node cell mixtures. The slope of the response of cell mixtures was noted to be significantly greater than the slope for the response of lympth node cells alone. Irradiation was shown to have a differential effect on the response of thymus and lymph node cells in mixtures. Irradiated thymus cells retained the capacity for synergy in mixtures, whereas irradiated lymph node cells did not. Additional studies have demonstrated that both de novo protein synthesis and specific antigen recognition by both responding cell populations in mixtures was required for maximal synergy. These studies demonstrate that synergy cannot be explained as an artifact of altered cell density in vitro. They establish that thymus cells and lymph node cells represent distinct subsets which manifest qualitatively different functions in the proliferative response to alloantigen. Thymus cells can respond directly to alloantigen by proliferation but also have the capacity to amplify the proliferative response of lymph node cells, a capacity which is resistant to X irradiation but requires recognition of alloantigen and de novo protein synthesis. Lymph node cells may similarly respond by proliferation to alloantigen but lack the amplifier activity of thymus cells. Synergy for rat lymphoidcells, like mouse lymphoid cells, has been shown to involve an interaction of thymus-derived lymphocytes

  14. Biophysical interpretation of the response of Chinese hamster cells to 24 keV neutrons

    International Nuclear Information System (INIS)

    Holt, P.D.

    1988-01-01

    The response of V79 Chinese hamster cells to a 24 keV neutron spectrum has been compared with data for the response of V79 cells to a range of higher neutron energies (up to 15 MeV). The linear energy transfer (LET) distributions of the neutron spectra were calculated and the expected responses of the cells to the different spectra were calculated using published track-segment data on the response of V79 cells to charged particles with various LET values. The response of the cells to 24 keV neutrons was predicted satisfactorily by the LET distribution, in spite of the fact that the maximum range of the recoil protons is only 0.5 μm. The response was not correctly predicted by the microdosimetric parameter y-bar D * evaluated in a 1 μm diameter sphere. (author)

  15. Evidence for a specific glutamate/H+ cotransport in isolated mesophyll cells

    International Nuclear Information System (INIS)

    McCutcheon, S.L.; Bown, A.W.

    1987-01-01

    Mechanically isolated Asparagus sprengeri Regel mesophyll cells were suspended in 1 millimolar CaSO 4 . Immediate alkalinization of the medium occurred on the addition of 1 millimolar concentrations of L-glutamate (Glu) and its analog L-methionine-D,L-sulfoximine (L-MSO). D-Glu and the L isomers of the protein amino acids did not elicit alkalinization. L-Glu dependent alkalinization was transient and acidification resumed after approximately 30 to 45 minutes. At pH 6.0, 5 millimolar L-Glu stimulated initial rates of alkalinization that varied between 1.3 to 4.1 nmol H + /10 6 cells minute. L-Glu dependent alkalinization was saturable, increased with decreasing pH, was inhibited by carbonyl cyanide-p-trichloromethoxyphenyl hydrazone (CCCP), and was not stimulated by light. Uptake of L-[U- 14 C]glutamate increased as the pH decreased from 6.5 to 5.5, and was inhibited by L-MSO. L-Glu had no influence on K + efflux. Although evidence for multiple amino acid/proton cotransport systems has been found in other tissues, the present report indicates that a highly specific L-Glu/proton uptake process is present in Asparagus mesophyll cells

  16. Arsenite and monomethylarsonous acid generate oxidative stress respon