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Sample records for cell responses evidence

  1. No Evidence for a Low Linear Energy Transfer Adaptive Response in Irradiated RKO Cells

    Energy Technology Data Exchange (ETDEWEB)

    Sowa, Marianne B.; Goetz, Wilfried; Baulch, Janet E.; Lewis, Adam J.; Morgan, William F.

    2011-01-06

    It has become increasingly evident from reports in the literature that there are many confounding factors that are capable of modulating radiation induced non-targeted responses such as the bystander effect and the adaptive response. In this paper we examine recent data that suggest that the observation of non-targeted responses may not be universally observable for differing radiation qualities. We have conducted a study of the adaptive response following low LET exposures for human colon carcinoma cells and failed to observe adaption for the endpoints of clonogenic survival or micronucleus formation.

  2. 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.

  3. Lack of evidence for low-LET radiation induced bystander response in normal human fibroblasts and colon carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Sowa, Marianne B.; Goetz, Wilfried; Baulch, Janet E.; Pyles, Dinah N.; Dziegielewski, J.; Yovino, Susannah; Snyder, Andrew R.; de Toledo, S. M.; Azzam, Edouard I.; Morgan, William F.

    2010-02-01

    The conventional paradigm in radiation biology has been that DNA is the primary target for energy deposition following exposure to ionizing radiation. However, studies focusing on the non-target effects of radiation, i.e. effects occurring in cells not directly exposed to radiation, imply that the target of exposure is larger than what has traditionally been assumed and could have significant implications for radiation health risks. We have conducted an extensive study of the low-LET bystander effect including multiple cell lines and endpoints and various radiation sources and exposure scenarios. In no instance do we see evidence of a low-LET induced bystander effect. However, direct comparison for alpha particle exposure showed a statistically significant media transfer bystander effect for high-LET but not for low-LET radiation. From our results it is evident that there are many confounding factors mitigating bystander responses as reported in the literature and for the cell lines we studied that there is a LET dependence for the observed responses. Our observations reflect the inherent variability in biological systems and the difficulties in extrapolating from in vitro models to radiation risks in humans.

  4. Predictive factors of response to treatment in patients with metastatic renal cell carcinoma: new evidence.

    Science.gov (United States)

    Tonini, Giuseppe; Fratto, Maria Elisabetta; Imperatori, Marco; Pantano, Francesco; Vincenzi, Bruno; Santini, Daniele

    2011-06-01

    Renal cell carcinoma represents approximately 3% of adult malignancies and 90-95% of neoplasms arising from the kidney. Many agents that target angiogenesis (e.g., sunitinib, sorafenib, bevacizumab and pazopanib) and mTOR-targeted therapy (e.g., temsirolimus and everolimus) have been approved as first-line agents. The choice of the most suitable treatment for advanced renal cell carcinoma depends on the definition of risk. In this article, we reviewed the scientific literature identifying predictive factors on the activity/efficacy of a specific therapy.

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

    Science.gov (United States)

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

    2015-11-01

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

  6. 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.

  7. Reassessing the role of HLA-DRB3 T-cell responses: evidence for significant expression and complementary antigen presentation.

    Science.gov (United States)

    Faner, Rosa; James, Eddie; Huston, Laurie; Pujol-Borrel, Ricardo; Kwok, William W; Juan, Manel

    2010-01-01

    In humans, several HLA-DRB loci (DRB1/3/4/5) encode diverse beta-chains that pair with alpha-chains to form DR molecules on the surface of APC. While DRB1 and DRB5 have been extensively studied, the role of DRB3/4 products of DR52/DR53 haplotypes has been largely neglected. To clarify the relative expression of DRB3, we quantified DRB3 mRNA levels in comparison with DRB1 mRNA from the same haplotype in both B cells and monocytes, observing quantitatively significant DRB3 synthesis. In CD19+ cells, DRB1*03/11/13 was 3.5-fold more abundant than DRB3, but in CD14+ this difference was only two-fold. Monocytes also had lower overall levels of DR mRNA compared with B cells, which was confirmed by cell surface staining of DRB1 and DRB3. To evaluate the functional role of DRB3, tetramer-guided epitope mapping was used to detect T cells against tetanus toxin and several influenza antigens presented by DRB3*0101/0202 or DRB1*03/11/13. None of the epitopes discovered were shared among any of the DR molecules. Quantitative assessment of DRB3-tetanus toxin specific T cells revealed that they are present at similar frequencies as those observed for DRB1. These results suggest that DRB3 plays a significant role in antigen presentation with different epitopic preferences to DRB1. Therefore, DRB3, like DRB5, serves to extend and complement the peptide repertoire of DRB1 in antigen presentation.

  8. 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

  9. Reassessing the role of HLA-DRB3 T cell responses: Evidence for significant expression and complementary antigen presentation

    OpenAIRE

    Faner, Rosa; James, Eddie; Huston, Laurie; Pujol-Borrel, Ricardo; William W Kwok; Juan, Manel

    2010-01-01

    In humans, several HLA-DRB loci (DRB1/3/4/5) encode diverse beta-chains which pair with alpha-chains to form DR molecules on the surface of APC. While DRB1 and DRB5 have been extensively studied, the role of DRB3/4 products of DR52/DR53 haplotypes has been largely neglected. To clarify the relative expression of DRB3, we quantified DRB3 mRNA levels in comparison with DRB1 mRNA from the same haplotype in both B cells and monocytes, observing quantitatively significant DRB3 synthesis. In CD19+ ...

  10. Dendritic cells and macrophages in the pituitary and the gonads. Evidence for their role in the fine regulation of the reproductive endocrine response

    NARCIS (Netherlands)

    Hoek, A; Allaerts, W; Leenen, PJM; Schoemaker, J; Drexhage, HA

    1997-01-01

    Blood monocytes are able to mature into macrophages as well as into dendritic cells, Dendritic cells and macrophages have mainly been studied for their function in the immune response, e.g. in the presentation of antigens to lymphocytes and in the phagocytosis/degradation of unwanted material. The c

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. CXC chemokine ligand 10 controls viral infection in the central nervous system: evidence for a role in innate immune response through recruitment and activation of natural killer cells.

    Science.gov (United States)

    Trifilo, Matthew J; Montalto-Morrison, Cynthia; Stiles, Linda N; Hurst, Kelley R; Hardison, Jenny L; Manning, Jerry E; Masters, Paul S; Lane, Thomas E

    2004-01-01

    How chemokines shape the immune response to viral infection of the central nervous system (CNS) has largely been considered within the context of recruitment and activation of antigen-specific lymphocytes. However, chemokines are expressed early following viral infection, suggesting an important role in coordinating innate immune responses. Herein, we evaluated the contributions of CXC chemokine ligand 10 (CXCL10) in promoting innate defense mechanisms following coronavirus infection of the CNS. Intracerebral infection of RAG1(-/-) mice with a recombinant CXCL10-expressing murine coronavirus (mouse hepatitis virus) resulted in protection from disease and increased survival that correlated with a significant increase in recruitment and activation of natural killer (NK) cells within the CNS. Accumulation of NK cells resulted in a reduction in viral titers that was dependent on gamma interferon secretion. These results indicate that CXCL10 expression plays a pivotal role in defense following coronavirus infection of the CNS by enhancing innate immune responses.

  13. 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....

  14. CXC Chemokine Ligand 10 Controls Viral Infection in the Central Nervous System: Evidence for a Role in Innate Immune Response through Recruitment and Activation of Natural Killer Cells

    OpenAIRE

    Trifilo, Matthew J.; Montalto-Morrison, Cynthia; Stiles, Linda N.; Hurst, Kelley R.; Hardison, Jenny L.; Manning, Jerry E.; Masters, Paul S.; Lane, Thomas E.

    2004-01-01

    How chemokines shape the immune response to viral infection of the central nervous system (CNS) has largely been considered within the context of recruitment and activation of antigen-specific lymphocytes. However, chemokines are expressed early following viral infection, suggesting an important role in coordinating innate immune responses. Herein, we evaluated the contributions of CXC chemokine ligand 10 (CXCL10) in promoting innate defense mechanisms following coronavirus infection of the C...

  15. Cell-mediated immune response

    DEFF Research Database (Denmark)

    Meyer, Sonja Izquierdo; Fuglsang, Katrine; Blaakaer, Jan

    2014-01-01

    OBJECTIVE: This clinical review aims to assess the efficacy of human papillomavirus 16/18 (HPV16/18) vaccination on the cell-mediated immune response in women with existing cervical intraepithelial neoplasia or cervical cancer induced by HPV16 or HPV18. DATA SOURCES AND STUDY SELECTION: A focused...... and thorough literature search conducted in five different databases found 996 publications. Six relevant articles were chosen for further review. In total, 154 patients (>18 years of age) were enrolled in prospective study trials with 3-15 months of follow up. The vaccine applications were administered two...... triggered a detectable cell-mediated immune response, some of which were statistically significant. Correlations between immunological response and clinical outcome (histopathology) were not significant, so neoplasms may not be susceptible to vaccine-generated cytotoxic T cells (CD8(+)). CONCLUSIONS...

  16. In vivo evidence for dendritic cell lysis by NK cells

    OpenAIRE

    Ferlazzo, Guido

    2012-01-01

    By using an experimental model of anticancer vaccination, we have recently lent support to the assumption, so far only sustained by in vitro data, that natural killer cells can restrain less immunogenic, allegedly tolerogenic, dendritic cells (DCs). This in vivo selection of immunogenic DCs appears to depend on perforin and to be associated with a more protective tumor-specific T lymphocyte response.

  17. 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.

  18. Evidence of a role for Th17 cells in the breach of immune tolerance in arthritis

    OpenAIRE

    Yu, Xinhua; Ibrahim, Saleh M.

    2011-01-01

    Th17 cells are thought to play a pathogenic role in various autoimmune diseases. Cytokines secreted by Th17 cells like IL-17, IL-17F and IL-22 have the capacity to mediate a massive inflammatory response. These proinflammatroy cytokines are likely to mediate the pathogenic potential of Th17 cells. Recent evidence suggests a role for Th17 cells in the breach of immune tolerance. This might shed some new light on the pathogenic role of Th17 cells in autoimmunity.

  19. Pharmacokinetic and Pharmacodynamic Responses to Clopidogrel: Evidences and Perspectives

    Science.gov (United States)

    Zhang, Yan-Jiao; Li, Mu-Peng; Tang, Jie; Chen, Xiao-Ping

    2017-01-01

    Clopidogrel has significantly reduced the incidence of recurrent atherothrombotic events in patients with acute coronary syndrome (ACS) and in those undergoing percutaneous coronary intervention (PCI). However, recurrence events still remain, which may be partly due to inadequate platelet inhibition by standard clopidogrel therapy. Genetic polymorphisms involved in clopidogrel’s absorption, metabolism, and the P2Y12 receptor may interfere with its antiplatelet activity. Recent evidence indicated that epigenetic modification may also affect clopidogrel response. In addition, non-genetic factors such as demographics, disease complications, and drug-drug interactions can impair the antiplatelet effect of clopidogrel. The identification of factors contributing to the variation in clopidogrel response is needed to improve platelet inhibition and to reduce risk for cardiovascular events. This review encompasses the most recent updates on factors influencing pharmacokinetic and pharmacodynamic responses to clopidogrel. PMID:28335443

  20. The STATs in cell stress-type responses

    Directory of Open Access Journals (Sweden)

    Best James

    2004-08-01

    Full Text Available Abstract In the early 1990's, a new cell signaling pathway was described. This new paradigm, now known as the JAK/STAT pathway, has been extensively investigated in immune-type cells in response to interferons and interleukins. However, recent evidence suggests that the JAK/STAT pathway also mediates diverse cellular responses to various forms of biological stress including hypoxia/reperfusion, endotoxin, ultraviolet light, and hyperosmolarity. The current literature describing the JAK/STAT pathway's role in cellular stress responses has been reviewed herein, but it is clear that our knowledge in this area is far from complete.

  1. 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

  2. ShcA regulates neurite outgrowth stimulated by neural cell adhesion molecule but not by fibroblast growth factor 2: evidence for a distinct fibroblast growth factor receptor response to neural cell adhesion molecule activation

    DEFF Research Database (Denmark)

    Hinsby, Anders M; Lundfald, Line; Ditlevsen, Dorte K;

    2004-01-01

    by two principal routes of signaling: NCAM/Fyn and NCAM/fibroblast growth factor receptor (FGFR), respectively. Previous studies have shown that activation of mitogen-activated protein kinases is a pivotal point of convergence in NCAM signaling, but the mechanisms behind this activation are not clear....... Here, we investigated the involvement of adaptor proteins in NCAM and fibroblast growth factor 2 (FGF2)-mediated neurite outgrowth in the PC12-E2 cell line. We found that both FGFR substrate-2 and Grb2 play important roles in NCAM as well as in FGF2-stimulated events. In contrast, the docking protein...... ShcA was pivotal to neurite outgrowth induced by NCAM, but not by FGF2, in PC12 cells. Moreover, in rat cerebellar granule neurons, phosphorylation of ShcA was stimulated by an NCAM mimicking peptide, but not by FGF2. This activation was blocked by inhibitors of both FGFR and Fyn, indicating that NCAM...

  3. Controlled surface chemistries and quantitative cell response

    Science.gov (United States)

    Plant, Anne L.

    2002-03-01

    Living cells experience a large number of signaling cues from their extracellular matrix. As a result of these inputs, a variety of intracellular signaling pathways are apparently initiated simultaneously. The vast array of alternative responses that result from the integration of these inputs suggests that it may be reasonable to look for cellular response not as an 'on' or 'off' condition but as a distribution of responses. A difficult challenge is to determine whether variations in responses from individual cells arise from the complexity of intracellular signals or are due to variations in the cell culture environment. By controlling surface chemistry so that every cell 'sees' the same chemical and physical environment, we can begin to assess how the distribution of cell response is affected strictly by changes in the chemistry of the cell culture surface. Using the gene for green fluorescent protein linked to the gene for the promoter of the extracellular matrix protein, tenascin, we can easily probe the end product in a signaling pathway that is purported to be linked to surface protein chemistry and to cell shape. Cell response to well-controlled, well-characterized, and highly reproducible surfaces prepared using soft lithography techniques are compared with more conventional ways of preparing extracellular matrix proteins for cell culture. Using fluorescence microscopy and image analysis of populations of cells on these surfaces, we probe quantitatively the relationship between surface chemistry, cell shape and variations in gene expression endpoint.

  4. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Cappers, Peter; Goldman, Charles; Kathan, David

    2009-06-01

    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.

  6. 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.

  7. CD4+ T cell responses in hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Nasser Semmo; Paul Klenerman

    2007-01-01

    Hepatitis C virus (HCV) infection is a major cause of liver damage, with virus-induced end-stage disease such as liver cirrhosis and hepatocellular carcinoma resulting in a high rate of morbidity and mortality worldwide. Evidence that CD4+ T cell responses to HCV play an important role in the outcome of acute infection has been shown in several studies. However, the mechanisms behind viral persistence and the failure of CD4+ T cell responses to contain virus are poorly understood. During chronic HCV infection, HCV-specific CD4+ T cell responses are relatively weak or absent whereas in resolved infection these responses are vigorous and multispecific. Persons with a T-helper type Ⅰ profile, which promotes cellular effector mechanisms are thought to be more likely to experience viral clearance, but the overall role of these cells in the immunopathogenesis of chronic liver disease is not known. To define this, much more data is required on the function and specificity of virus-specific CD4+ T cells,especially in the early phases of acute disease and in the liver during chronic infection. The role and possible mechanisms of action of CD4+ T cell responses in determining the outcome of acute and chronic HCV infection will be discussed in this review.

  8. 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.

  9. DNA damage response in adult stem cells.

    Science.gov (United States)

    Insinga, Alessandra; Cicalese, Angelo; Pelicci, Pier Giuseppe

    2014-04-01

    This review discusses the processes of DNA-damage-response and DNA-damage repair in stem and progenitor cells of several tissues. The long life-span of stem cells suggests that they may respond differently to DNA damage than their downstream progeny and, indeed, studies have begun to elucidate the unique stem cell response mechanisms to DNA damage. Because the DNA damage responses in stem cells and progenitor cells are distinctly different, stem and progenitor cells should be considered as two different entities from this point of view. Hematopoietic and mammary stem cells display a unique DNA-damage response, which involves active inhibition of apoptosis, entry into the cell-cycle, symmetric division, partial DNA repair and maintenance of self-renewal. Each of these biological events depends on the up-regulation of the cell-cycle inhibitor p21. Moreover, inhibition of apoptosis and symmetric stem cell division are the consequence of the down-regulation of the tumor suppressor p53, as a direct result of p21 up-regulation. A deeper understanding of these processes is required before these findings can be translated into human anti-aging and anti-cancer therapies. One needs to clarify and dissect the pathways that control p21 regulation in normal and cancer stem cells and define (a) how p21 blocks p53 functions in stem cells and (b) how p21 promotes DNA repair in stem cells. Is this effect dependent on p21s ability to inhibit p53? Such molecular knowledge may pave the way to methods for maintaining short-term tissue reconstitution while retaining long-term cellular and genomic integrity.

  10. Mast cells and basophils in cutaneous immune responses.

    Science.gov (United States)

    Otsuka, A; Kabashima, K

    2015-02-01

    Mast cells and basophils share some functions in common and are generally associated with T helper 2 (Th2) immune responses, but taking basophils as surrogate cells for mast cell research or vice versa for several decades is problematic. Thus far, their in vitro functions have been well studied, but their in vivo functions remained poorly understood. New research tools for their functional analysis in vivo have revealed previously unrecognized roles for mast cells and basophils in several skin disorders. Newly developed mast cell-deficient mice provided evidence that mast cells initiate contact hypersensitivity via activating dendritic cells. In addition, studies using basophil-deficient mice have revealed that basophils were responsible for cutaneous Th2 skewing to haptens and peptide antigens but not to protein antigens. Moreover, human basophils infiltrate different skin lesions and have been implicated in the pathogenesis of skin diseases ranging from atopic dermatitis to autoimmune diseases. In this review, we will discuss the recent advances related to mast cells and basophils in human and murine cutaneous immune responses.

  11. 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.

  12. Cell mechanics: integrating cell responses to mechanical stimuli.

    Science.gov (United States)

    Janmey, Paul A; McCulloch, Christopher A

    2007-01-01

    Forces are increasingly recognized as major regulators of cell structure and function, and the mechanical properties of cells are essential to the mechanisms by which cells sense forces, transmit them to the cell interior or to other cells, and transduce them into chemical signals that impact a spectrum of cellular responses. Comparison of the mechanical properties of intact cells with those of the purified cytoskeletal biopolymers that are thought to dominate their elasticity reveal the extent to which the studies of purified systems can account for the mechanical properties of the much more heterogeneous and complex cell. This review summarizes selected aspects of current work on cell mechanics with an emphasis on the structures that are activated in cell-cell contacts, that regulate ion flow across the plasma membrane, and that may sense fluid flow that produces low levels of shear stress.

  13. Interleukin-21 triggers effector cell responses in the gut

    Institute of Scientific and Technical Information of China (English)

    Daniela; De; Nitto; Massimiliano; Sarra; Francesco; Pallone; Giovanni; Monteleone

    2010-01-01

    In the gut of patients with Crohn's disease and patients with ulcerative colitis,the major forms of inflammatory bowel diseases(IBD) in humans,the tissue-damaging immune response is mediated by an active cross-talk between immune and non-immune cells.Accumulating evidence indicates also that cytokines produced by these cells play a major role in initiating and shaping this pathologic process.One such cytokine seems to be interleukin(IL)-21,a member of the common γ-chainreceptor family.IL-21 is produced in e...

  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.

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

    Directory of Open Access Journals (Sweden)

    Biswapriya B Misra

    Full Text Available 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.

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

    Science.gov (United States)

    Hulme, Philip E

    2016-05-31

    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

  17. 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

  18. T cell responses and dengue haemorrhagic fever.

    Science.gov (United States)

    Screaton, Gavin; Mongkolsapaya, Juthathip

    2006-01-01

    The enhancement of severe disease upon secondary infection makes dengue almost unique among infectious pathogens and presents a serious challenge to vaccine design. Several key observations have been made which shed light onto this phenomenon particularly that antibodies can enhance Fc receptor-dependent uptake of virus into macrophages thereby increasing virus replication. Furthermore there seems to be a relationship between the peak virus load and disease severity. However, a second key feature of dengue is that the life-threatening symptoms do not correlate with the period of high viraemia; instead they occur at a time when the virus load is in steep decline. The coincidence of severe disease manifestations with defervescence and virus control suggests that the symptoms may be a consequence of the immune response to the virus rather than virus induced cytopathology. One of the key elements in the immune response to viruses are T cells which can both secrete a host of inflammatory cytokines and also be directly cytotoxic to infected cells. There are a number of experimental models of T cell-induced immunopathology including in responses to viruses. Particularly interesting in this respect are models of RSV-induced immunopathology, which have direct relevance to vaccine design as a formalin-inactivated vaccine to RSV actually enhanced disease in children when they became naturally infected with RSV, an echo of the disease enhancement seen in dengue. We will present an analysis of CD8+ T cell responses to a number of novel T cell epitopes during dengue infection and also analyse the function and cytokine secretion of these cells. We suggest that an exaggerated and partially misdirected T cell response seen in secondary dengue infection may be part of the complex series of events leading to dengue haemorrhagic fever and shock.

  19. 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....

  20. Human Macrophage Response to L. (Viannia) panamensis: Microarray Evidence for an Early Inflammatory Response

    Science.gov (United States)

    Rojas, Ricardo; Ettinger, Nicholas A.; Tikhonova, Irina; Alexander, Neal D.; Valderrama, Liliana; Hager, Janet; Wilson, Mary E.; Lin, Aiping; Zhao, Hongyu; Saravia, Nancy G.; McMahon-Pratt, Diane

    2012-01-01

    dynamics of these interactions and the distinct biologic responses to different Leishmania species from the outset of infection within their primary host cell. PMID:23145196

  1. Antigen selection in B-cell lymphomas--tracing the evidence.

    Science.gov (United States)

    Sutton, Lesley-Ann; Agathangelidis, Andreas; Belessi, Chrysoula; Darzentas, Nikos; Davi, Frederic; Ghia, Paolo; Rosenquist, Richard; Stamatopoulos, Kostas

    2013-12-01

    While signaling through the B cell receptor (BcR) facilitates B cell development and maintenance, it also carries intertwined risks for the development of lymphomas since malignant B cells can exploit these pathways in order to trigger and fuel clonal expansion. This corruption of the normal B cell response to antigens, leading to sustained BcR signaling, has given great impulse to investigate in detail the role of antigen in lymphomas. Suffice it to conclude from such studies, largely immunogenetics based, that the evidence implicating antigens (exogenous or self) in lymphoma development is substantial and that lymphomagenesis is functionally driven and dynamic, rather than a simple stochastic process. As the paradigm of antigen-driven lymphoma evolves, further investigation will be paramount to the identification of the inciting agent(s) that may be responsible for immunoproliferative neoplasms and also for the development of therapeutic agents targeting effectors of the BcR signaling pathway.

  2. Regulation of B Cell to Plasma Cell Transition within the Follicular B Cell Response.

    Science.gov (United States)

    Nera, K-P; Kyläniemi, M K; Lassila, O

    2015-09-01

    Persistent humoral immunity depends on the follicular B cell response and on the generation of somatically mutated high-affinity plasma cells and memory B cells. Upon activation by an antigen, cognately activated follicular B cells and follicular T helper (TFH ) cells initiate germinal centre (GC) reaction during which high-affinity effector cells are generated. The differentiation of activated follicular B cells into plasma cells and memory B cells is guided by complex selection events, both at the cellular and molecular level. The transition of B cell into a plasma cell during the GC response involves alterations in the microenvironment and developmental state of the cell, which are guided by cell-extrinsic signals. The developmental cell fate decisions in response to these signals are coordinated by cell-intrinsic gene regulatory network functioning at epigenetic, transcriptional and post-transcriptional levels.

  3. Fibroblast nemosis induces angiogenic responses of endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Enzerink, Anna, E-mail: anna.enzerink@helsinki.fi [Haartman Institute, University of Helsinki, P.O. BOX 21, FIN-00014 Helsinki (Finland); Rantanen, Ville, E-mail: ville.rantanen@helsinki.fi [Computational Systems Biology Laboratory, Institute of Biomedicine and Genome-Scale Biology Research Program, University of Helsinki, P.O. BOX 63, 00014 Helsinki (Finland); Vaheri, Antti, E-mail: antti.vaheri@helsinki.fi [Haartman Institute, University of Helsinki, P.O. BOX 21, FIN-00014 Helsinki (Finland)

    2010-03-10

    Increasing evidence points to a central link between inflammation and activation of the stroma, especially of fibroblasts therein. However, the mechanisms leading to such activation mostly remain undescribed. We have previously characterized a novel type of fibroblast activation (nemosis) where clustered fibroblasts upregulated the production of cyclooxygenase-2, secretion of prostaglandins, proteinases, chemotactic cytokines, and hepatocyte growth factor (HGF), and displayed activated nuclear factor-{kappa}B. Now we show that nemosis drives angiogenic responses of endothelial cells. In addition to HGF, nemotic fibroblasts secreted vascular endothelial growth factor (VEGF), and conditioned medium from spheroids promoted sprouting and networking of human umbilical venous endothelial cells (HUVEC). The response was partly inhibited by function-blocking antibodies against HGF and VEGF. Conditioned nemotic fibroblast medium promoted closure of HUVEC and human dermal microvascular endothelial cell monolayer wounds, by increasing the motility of the endothelial cells. Wound closure in HUVEC cells was partly inhibited by the antibodies against HGF. The stromal microenvironment regulates wound healing responses and often promotes tumorigenesis. Nemosis offers clues to the activation process of stromal fibroblasts and provides a model to study the part they play in angiogenesis-related conditions, as well as possibilities for therapeutical approaches desiring angiogenesis in tissue.

  4. 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.

  5. Airway epithelial cell responses to ozone injury

    Energy Technology Data Exchange (ETDEWEB)

    Leikauf, G.D.; Simpson, L.G.; Zhao, Qiyu [Univ. of Cincinnati Medical Center, OH (United States)] [and others

    1995-03-01

    The airway epithelial cell is an important target in ozone injury. Once activated, the airway epithelium responds in three phases. The initial, or immediate phase, involves activation of constitutive cells, often through direct covalent interactions including the formation of secondary ozonolysis products-hydroxyhydroperoxides, aldehydes, and hydrogen peroxide. Recently, we found hydroxyhydroperoxides to be potent agonists; of bioactive eicosanoid formation by human airway epithelial cells in culture. Other probable immediate events include activation and inactivation of enzymes present on the epithelial surface (e.g., neutral endopeptidase). During the next 2 to 24 hr, or early phase, epithelial cells respond by synthesis and release of chemotactic factors, including chemokines-macrophage inflammatory protein-2, RANTES, and interleukin-8. Infiltrating leukocytes during this period also release elastase, an important agonist of epithelial cell mucus secretion and additional chemokine formation. The third (late) phase of ozone injury is characterized by eosinophil or monocyte infiltration. Cytokine expression leads to alteration of structural protein synthesis, with increases in fibronectin evident by in situ hybridization. Synthesis of epithelial antiproteases, e.g., secretary leukocyte protease inhibitor, may also increase locally 24 to 48 hr after elastase concentrations become excessive. Thus, the epithelium is not merely a passive barrier to ozone injury but has a dynamic role in directing the migration, activating, and then counteracting inflammatory cells. Through these complex interactions, epithelial cells can be viewed as the initiators (alpha) and the receptors (omega) of ozone-induced airway disease. 51 refs., 2 figs., 3 tabs.

  6. The Metabolism of the Pancreas Carcinogen N-nitrosobis(2-oxopropylAmine by Hamster Pancreas Duct Epithelial Cell Clones; Evidence for Different Metabolic Efficiencies and Response to Cytochrome P450 Inducers

    Directory of Open Access Journals (Sweden)

    Kolar C

    2000-05-01

    Full Text Available CONTEXT: We have isolated five stable clones from a primary culture of Syrian golden hamster pancreatic duct epithelial cells and have designated them as CK1 through CK5. DESIGN: Here we describe the ability of two of these, CK1 and CK5, to metabolize the pancreas carcinogen N-nitrosobis(2-oxopropylamine. The metabolism was assessed as the production of mutated V79 cells in a CK cell/V79 co-culture set up. RESULTS: At a dose of 0.1 mM N-nitrosobis(2-oxopropylamine, the CK1 cells produced 82.3 +/- 17.2 mutants/1,000,000 survivors while the CK5 cells produced only 33.2 +/- 10.8 mutants/1,000,000 survivors, both are mean +/- SD (n = 8. Furthermore, both cell types responded differently to two inducers of cytochrome P450 activity, namely Arochlor 1254 and EtOH. Arochlor 1254 treatment did not affect the metabolizing ability of CK1 cells while EtOH treatment resulted in a twofold increase in the mutation frequency. Arochlor and EtOH treatment inhibited the ability of CK5 cells to metabolize N-nitrosobis(2-oxopropylamine. CONCLUSIONS: These data show that the duct epithelium of the pancreas is a multi-cellular tissue and the different cell types within the epithelium have different abilities to metabolize xenobiotic chemicals.

  7. 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

  8. Cell identity regulators link development and stress responses in the Arabidopsis root.

    Science.gov (United States)

    Iyer-Pascuzzi, Anjali S; Jackson, Terry; Cui, Hongchang; Petricka, Jalean J; Busch, Wolfgang; Tsukagoshi, Hironaka; Benfey, Philip N

    2011-10-18

    Stress responses in plants are tightly coordinated with developmental processes, but interaction of these pathways is poorly understood. We used genome-wide assays at high spatiotemporal resolution to understand the processes that link development and stress in the Arabidopsis root. Our meta-analysis finds little evidence for a universal stress response. However, common stress responses appear to exist with many showing cell type specificity. Common stress responses may be mediated by cell identity regulators because mutations in these genes resulted in altered responses to stress. Evidence for a direct role for cell identity regulators came from genome-wide binding profiling of the key regulator SCARECROW, which showed binding to regulatory regions of stress-responsive genes. Coexpression in response to stress was used to identify genes involved in specific developmental processes. These results reveal surprising linkages between stress and development at cellular resolution, and show the power of multiple genome-wide data sets to elucidate biological processes.

  9. Blobs versus bars: psychophysical evidence supports two types of orientation response in human color vision.

    Science.gov (United States)

    Gheiratmand, Mina; Meese, Tim S; Mullen, Kathy T

    2013-01-02

    The classic hypothesis of Livingstone and Hubel (1984, 1987) proposed two types of color pathways in primate visual cortex based on recordings from single cells: a segregated, modular pathway that signals color but provides little information about shape or form and a second pathway that signals color differences and so defines forms without the need to specify their colors. A major problem has been to reconcile this neurophysiological hypothesis with the behavioral data. A wealth of psychophysical studies has demonstrated that color vision has orientation-tuned responses and little impairment on form related tasks, but these have not revealed any direct evidence for nonoriented mechanisms. Here we use a psychophysical method of subthreshold summation across orthogonal orientations for isoluminant red-green gratings in monocular and dichoptic viewing conditions to differentiate between nonoriented and orientation-tuned responses to color contrast. We reveal nonoriented color responses at low spatial frequencies (0.25-0.375 c/deg) under monocular conditions changing to orientation-tuned responses at higher spatial frequencies (1.5 c/deg) and under binocular conditions. We suggest that two distinct pathways coexist in color vision at the behavioral level, revealed at different spatial scales: one is isotropic, monocular, and best equipped for the representation of surface color, and the other is orientation-tuned, binocular, and selective for shape and form. This advances our understanding of the organization of the neural pathways involved in human color vision and provides a strong link between neurophysiological and behavioral data.

  10. Cellular immune responses towards regulatory cells.

    Science.gov (United States)

    Larsen, Stine Kiær

    2016-01-01

    This thesis describes the results from two published papers identifying spontaneous cellular immune responses against the transcription factors Foxp3 and Foxo3. The tumor microenvironment is infiltrated by cells that hinder effective tumor immunity from developing. Two of these cell types, which have been linked to a bad prognosis for patients, are regulatory T cells (Treg) and tolerogenic dendritic cells (DC). Tregs inhibit effector T cells from attacking the tumor through various mechanisms, including secreted factors and cell-to-cell contact. Tregs express the transcription factor Foxp3, which is necessary for their development and suppressive activities. Tolerogenic DCs participate in creating an environment in the tumor where effector T cells become tolerant towards the tumor instead of attacking it. The transcription factor Foxo3 was recently described to be highly expressed by tolerogenic DCs and to programme their tolerogenic influence. This thesis describes for the first time the existence of spontaneous cellular immune responses against peptides derived from Foxp3 and Foxo3. We have detected the presence of cytotoxic T cells that recognise these peptides in an HLA-A2 restricted manner in cancer patients and for Foxp3 in healthy donors as well. In addition, we have demonstrated that the Foxp3- and Foxo3-specific CTLs recognize Foxp3- and Foxo3-expressing cancer cell lines and importantly, suppressive immune cells, namely Tregs and in vitro generated DCs. Cancer immunotherapy is recently emerging as an important treatment modality improving the survival of selected patients. The current progress is largely owing to targeting of the immune suppressive milieu that is dominating the tumor microenvironment. This is being done through immune checkpoint blockade with CTLA-4 and PD-1/PD-L1 antibodies and through lymphodepleting conditioning of patients and ex vivo activation of TILs in adoptive cell transfer. Several strategies are being explored for depletion of

  11. Bystander T cells in human immune responses to dengue antigens

    Directory of Open Access Journals (Sweden)

    Suwannasaen Duangchan

    2010-09-01

    Full Text Available Abstract Background Previous studies of T cell activation in dengue infection have focused on restriction of specific T cell receptors (TCRs and classical MHC molecules. However, bystander T cell activation, which is TCR independent, occurs via cytokines in other viral infections, both in vitro and in vivo, and enables T cells to bypass certain control checkpoints. Moreover, clinical and pathological evidence has pointed to cytokines as the mediators of dengue disease severity. Therefore, we investigated bystander T cell induction by dengue viral antigen. Results Whole blood samples from 55 Thai schoolchildren aged 13-14 years were assayed for in vitro interferon-gamma (IFN-γ induction in response to inactivated dengue serotype 2 antigen (Den2. The contribution of TCR-dependent and independent pathways was tested by treatment with cyclosporin A (CsA, which inhibits TCR-dependent activation of T cells. ELISA results revealed that approximately 72% of IFN-γ production occurred via the TCR-dependent pathway. The major IFN-γ sources were natural killer (NK (mean ± SE = 55.2 ± 3.3, CD4+T (24.5 ± 3.3 and CD8+T cells (17.9 ± 1.5, respectively, as demonstrated by four-color flow cytometry. Interestingly, in addition to these cells, we found CsA-resistant IFN-γ producing T cells (CD4+T = 26.9 ± 3.6% and CD8+T = 20.3 ± 2.1% implying the existence of activated bystander T cells in response to dengue antigen in vitro. These bystander CD4+ and CD8+T cells had similar kinetics to NK cells, appeared after 12 h and were inhibited by anti-IL-12 neutralization indicating cytokine involvement. Conclusions This study described immune cell profiles and highlighted bystander T cell activation in response to dengue viral antigens of healthy people in an endemic area. Further studies on bystander T cell activation in dengue viral infection may reveal the immune mechanisms that protect or enhance pathogenesis of secondary dengue infection.

  12. Dendritic cells a double-edge sword in autoimmune responses

    Directory of Open Access Journals (Sweden)

    Giada eAmodio

    2012-08-01

    Full Text Available Dendritic cells (DC are antigen-presenting cells that play a pivotal role in regulating innate and adaptive immune responses. In autoimmunity, DC act as a double-edged sword since on one hand they initiate adaptive self-reactive responses and on the other they play a pivotal role in promoting and maintaining tolerance. Thus, DC are the most important cells in either triggering self-specific responses or in negatively regulating auto-reactive responses. DC in the steady state or specialized subsets of DC, named tolerogenic DC, are involved in the latter function. Clinical and experimental evidence indicate that prolonged presentation of self-antigens by DC is crucial for the development of destructive autoimmune diseases, and defects in tolerogenic DC functions contribute to eradication of self-tolerance. In recent years, DC have emerged as therapeutic targets for limiting their immunogenicity against self-antigens, while tolerogenic DC have been conceived as therapeutic tools to restore tolerance. The purpose of this review is to give a general overview of the current knowledge on the pathogenic role of DC in patients affected by autoimmune diseases. In addition, the protective role of tolerogenic DC will be addressed. The currently applied strategies to block immune activation or to exploit the tolerogenic potential of DC will be discussed.

  13. 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

  14. 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 re

  15. 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

  16. 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...

  17. Immunotherapy for small-cell lung cancer: emerging evidence.

    Science.gov (United States)

    Reck, Martin; Heigener, David; Reinmuth, Niels

    2016-04-01

    Treatment for small-cell lung cancer (SCLC) has changed little over the past few decades; available therapies have failed to extend survival in advanced disease. In recent years, immunotherapy with treatments such as interferons, TNFs, vaccines and immune checkpoint inhibitors has advanced and shown promise in the treatment of several tumor types. Immune checkpoint inhibitors such as ipilimumab, nivolumab, pembrolizumab, durvalumab, tremelimumab and ulocuplumab are at the forefront of immunotherapy and have achieved approvals for certain cancer types, including melanoma (ipilimumab, nivolumab and pembrolizumab), non-SCLC (nivolumab and pembrolizumab) and renal cell carcinoma (nivolumab). Clinical trials are investigating different immunotherapies in patients with other solid and hematologic malignancies, including SCLC. We review emerging evidence supporting the use of immunotherapy in SCLC patients.

  18. Increased virus replication in mammalian cells by blocking intracellular innate defense responses

    NARCIS (Netherlands)

    Vries, W. de; Haasnoot, J.; Velden, J. van der; Montfort, T. van; Zorgdrager, F.; Paxton, W.; Cornelissen, M.; Kuppeveld, F.J.M. van; Haan, P. de; Berkhout, B.

    2008-01-01

    The mammalian innate immune system senses viral infection by recognizing viral signatures and activates potent antiviral responses. Besides the interferon (IFN) response, there is accumulating evidence that RNA silencing or RNA interference (RNAi) serves as an antiviral mechanism in mammalian cells.

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    Lynette M. Sholl

    2011-10-01

    Full Text Available 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.

  1. Epitope-Specific Suppression of IgG Responses by Passively Administered Specific IgG: Evidence of Epitope Masking

    Science.gov (United States)

    Bergström, Joakim J. E.; Xu, Hui; Heyman, Birgitta

    2017-01-01

    Specific IgG, passively administered together with particulate antigen, can completely prevent induction of antibody responses to this antigen. The ability of IgG to suppress antibody responses to sheep red blood cells (SRBCs) is intact in mice lacking FcγRs, complement factor 1q, C3, or complement receptors 1 and 2, suggesting that Fc-dependent effector functions are not involved. Two of the most widely discussed explanations for the suppressive effect are increased clearance of IgG–antigen complexes and/or that IgG “hides” the antigen from recognition by specific B cells, so-called epitope masking. The majority of data on how IgG induces suppression was obtained through studies of the effects on IgM-secreting single spleen cells during the first week after immunization. Here, we show that IgG also suppresses antigen-specific extrafollicular antibody-secreting cells, germinal center B-cells, long-lived plasma cells, long-term IgG responses, and induction of memory antibody responses. IgG anti-SRBC reduced the amount of SRBC in the spleens of wild-type, but not of FcγR-deficient mice. However, no correlation between suppression and the amount of SRBC in the spleen was observed, suggesting that increased clearance does not explain IgG-mediated suppression. Instead, we found compelling evidence for epitope masking because IgG anti-NP administered with NP-SRBC suppressed the IgG anti-NP, but not the IgG anti-SRBC response. Vice versa, IgG anti-SRBC administered with NP-SRBC, suppressed only the IgG anti-SRBC response. In conclusion, passively transferred IgG suppressed all measured parameters of an antigen-specific antibody/B cell response and an important mechanism of action is likely to be epitope masking.

  2. 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...

  3. Mast Cells are Important Modifiers of Autoimmune Disease: With so Much Evidence, Why is There Still Controversy?

    Science.gov (United States)

    Brown, Melissa A; Hatfield, Julianne K

    2012-01-01

    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.

  4. Nitric Oxide And Hypoxia Response In Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Estefanía Caballano Infantes

    2015-08-01

    Full Text Available The expansion of pluripotent cells (ESCs and iPSCs under conditions that maintain their pluripotency is necessary to implement a cell therapy program. Previously, we have described that low nitric oxide (NO donor diethylenetriamine/nitric oxide adduct (DETA-NO added to the culture medium, promote the expansion of these cell types. The molecular mechanisms are not yet known. We present evidences that ESC and iPSCs in normoxia in presence of low NO triggers a similar response to hypoxia, thus maintaining the pluripotency. We have studied the stability of HIF-1α (Hypoxia Inducible Factor in presence of low NO. Because of the close relationship between hypoxia, metabolism, mitochondrial function and pluripotency we have analyzed by q RT-PCR the expression of genes involved in the glucose metabolism such as: HK2, LDHA and PDK1; besides other HIF-1α target gene. We further analyzed the expression of genes involved in mitochondrial biogenesis such as PGC1α, TFAM and NRF1 and we have observed that low NO maintains the same pattern of expression that in hypoxia. The study of the mitochondrial membrane potential using Mito-Tracker dye showed that NO decrease the mitochondrial function. We will analyze other metabolic parameters, to determinate if low NO regulates mitochondrial function and mimics Hypoxia Response. The knowledge of the role of NO in the Hypoxia Response and the mechanism that helps to maintain self-renewal in pluripotent cells in normoxia, can help to the design of culture media where NO could be optimal for stem cell expansion in the performance of future cell therapies.

  5. Contribution of Herpesvirus Specific CD8 T Cells to Anti-Viral T Cell Response in Humans

    OpenAIRE

    Elena Sandalova; Diletta Laccabue; Carolina Boni; Tan, Anthony T; Katja Fink; Eng Eong Ooi; Robert Chua; Bahar Shafaeddin Schreve; Carlo Ferrari; Antonio Bertoletti

    2010-01-01

    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, 1...

  6. DNA repair responses in human skin cells

    Energy Technology Data Exchange (ETDEWEB)

    Hanawalt, P.C.; Liu, S.C.; Parsons, C.S.

    1981-07-01

    Sunlight and some environmental chemical agents produce lesions in the DNA of human skin cells that if unrepaired may interfere with normal functioning of these cells. The most serious outcome of such interactions may be malignancy. It is therefore important to develop an understanding of mechanisms by which the lesions may be repaired or tolerated without deleterious consequences. Our models for the molecular processing of damaged DNA have been derived largely from the study of bacterial systems. Some similarities but significant differences are revealed when human cell responses are tested against these models. It is also of importance to learn DNA repair responses of epidermal keratinocytes for comparison with the more extensive studies that have been carried out with dermal fibroblasts. Our experimental results thus far indicate similarities for the excision-repair of ultraviolet-induced pyrimidine dimers in human keratinocytes and fibroblasts. Both the monoadducts and the interstrand crosslinks produced in DNA by photoactivated 8-methoxypsoralen (PUVA) can be repaired in normal human fibroblasts but not in those from xeroderma pigmentosum patients. The monoadducts, like pyrimidine dimers, are probably the more mutagenic/carcinogenic lesions while the crosslinks are less easily repaired and probably result in more effective blocking of DNA function. It is suggested that a split-dose protocol that maximizes the production of crosslinks while minimizing the yield of monoadducts may be more effective and potentially less carcinogenic than the single ultraviolet exposure regimen in PUVA therapy for psoriasis.

  7. 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

  8. Evidence for universality in phenomenological emotion response system coherence.

    Science.gov (United States)

    Matsumoto, David; Nezlek, John B; Koopmann, Birgit

    2007-02-01

    The authors reanalyzed data from Scherer and Wallbott's (Scherer, 1997b; Scherer & Wallbott, 1994) International Study of Emotion Antecedents and Reactions to examine how phenomenological reports of emotional experience, expression, and physiological sensations were related to each other within cultures and to determine if these relationships were moderated by cultural differences, which were operationally defined using Hofstede's (2001) typology. Multilevel random coefficient modeling analyses produced several findings of note. First, the vast majority of the variance in ratings was within countries (i.e., at the individual level); a much smaller proportion of the total variance was between countries. Second, there were negative relationships between country-level means and long- versus short-term orientation for numerous measures. Greater long-term orientation was associated with lowered emotional expressivity and fewer physiological sensations. Third, at the individual (within-culture) level, across the 7 emotions, there were consistent and reliable positive relationships among the response systems, indicating coherence among them. Fourth, such relationships were not moderated by cultural differences, as measured by the Hofstede dimensions.

  9. Host Cell Autophagy in Immune Response to Zoonotic Infections

    Directory of Open Access Journals (Sweden)

    Panagiotis Skendros

    2012-01-01

    Full Text Available Autophagy is a fundamental homeostatic process in which cytoplasmic targets are sequestered within double-membraned autophagosomes and subsequently delivered to lysosomes for degradation. Accumulating evidence supports the pivotal role of autophagy in host defense against intracellular pathogens implicating both innate and adaptive immunity. Many of these pathogens cause common zoonotic infections worldwide. The induction of the autophagic machinery by innate immune receptors signaling, such as TLRs, NOD1/2, and p62/SQSTM1 in antigen-presenting cells results in inhibition of survival and elimination of invading pathogens. Furthermore, Th1 cytokines induce the autophagic process, whereas autophagy also contributes to antigen processing and MHC class II presentation, linking innate to adaptive immunity. However, several pathogens have developed strategies to avoid autophagy or exploit autophagic machinery to their advantage. This paper focuses on the role of host cell autophagy in the regulation of immune response against intracellular pathogens, emphasizing on selected bacterial and protozoan zoonoses.

  10. Regulation of IgE Responses by γδ T Cells.

    Science.gov (United States)

    Huang, Yafei; Yang, Zhifang; McGowan, Jessica; Huang, Hua; O'Brien, Rebecca L; Born, Willi K

    2015-04-01

    Immunoglobulin E (IgE) antibodies play a crucial role in host defense against parasite infections. However, inappropriate IgE responses are also involved in the pathogenesis of allergic diseases. The generation of IgE antibodies is a tightly controlled process regulated by multiple transcription factors, cytokines, and immune cells including γδ T cells. Accumulating evidence demonstrates that γδ T cells play a critical role in regulating IgE responses; however, both IgE-enhancing and IgE-suppressive effects are suggested for these cells in different experimental systems. In this review, we examine the available evidence and discuss the role of γδ T cells in IgE regulation both in the context of antigen-induced immune responses and in the state of partial immunodeficiency.

  11. Interleukin-7 Modulates Anti-Tumor CD8+ T Cell Responses via Its Action on Host Cells

    Science.gov (United States)

    Deiser, Katrin; Stoycheva, Diana; Bank, Ute; Blankenstein, Thomas; Schüler, Thomas

    2016-01-01

    The adoptive transfer of antigen-specific CD8+ T cells is a promising approach for the treatment of chronic viral and malignant diseases. In order to improve adoptive T cell therapy (ATT) of cancer, recent strategies aim at the antibody-based blockade of immunosuppressive signaling pathways in CD8+ T cells. Alternatively, adjuvant effects of immunostimulatory cytokines might be exploited to improve therapeutic CD8+ T cell responses. For example, Interleukin-7 (IL-7) is a potent growth, activation and survival factor for CD8+ T cells that can be used to improve virus- and tumor-specific CD8+ T cell responses. Although direct IL-7 effects on CD8+ T cells were studied extensively in numerous models, the contribution of IL-7 receptor-competent (IL-7R+) host cells remained unclear. In the current study we provide evidence that CD8+ T cell-mediated tumor rejection in response to recombinant IL-7 (rIL-7) therapy is strictly dependent on IL-7R+ host cells. On the contrary, CD8+ T cell expansion is independent of host IL-7R expression. If, however, rIL-7 therapy and peptide vaccination are combined, host IL-7R signaling is crucial for CD8+ T cell expansion. Unexpectedly, maximum CD8+ T cell expansion relies mainly on IL-7R signaling in non-hematopoietic host cells, similar to the massive accumulation of dendritic cells and granulocytes. In summary, we provide evidence that IL-7R+ host cells are major targets of rIL-7 that modulate therapeutic CD8+ T cell responses and the outcome of rIL-7-assisted ATT. This knowledge may have important implications for the design and optimization of clinical ATT protocols. PMID:27447484

  12. Interleukin-7 Modulates Anti-Tumor CD8+ T Cell Responses via Its Action on Host Cells.

    Directory of Open Access Journals (Sweden)

    Katrin Deiser

    Full Text Available The adoptive transfer of antigen-specific CD8+ T cells is a promising approach for the treatment of chronic viral and malignant diseases. In order to improve adoptive T cell therapy (ATT of cancer, recent strategies aim at the antibody-based blockade of immunosuppressive signaling pathways in CD8+ T cells. Alternatively, adjuvant effects of immunostimulatory cytokines might be exploited to improve therapeutic CD8+ T cell responses. For example, Interleukin-7 (IL-7 is a potent growth, activation and survival factor for CD8+ T cells that can be used to improve virus- and tumor-specific CD8+ T cell responses. Although direct IL-7 effects on CD8+ T cells were studied extensively in numerous models, the contribution of IL-7 receptor-competent (IL-7R+ host cells remained unclear. In the current study we provide evidence that CD8+ T cell-mediated tumor rejection in response to recombinant IL-7 (rIL-7 therapy is strictly dependent on IL-7R+ host cells. On the contrary, CD8+ T cell expansion is independent of host IL-7R expression. If, however, rIL-7 therapy and peptide vaccination are combined, host IL-7R signaling is crucial for CD8+ T cell expansion. Unexpectedly, maximum CD8+ T cell expansion relies mainly on IL-7R signaling in non-hematopoietic host cells, similar to the massive accumulation of dendritic cells and granulocytes. In summary, we provide evidence that IL-7R+ host cells are major targets of rIL-7 that modulate therapeutic CD8+ T cell responses and the outcome of rIL-7-assisted ATT. This knowledge may have important implications for the design and optimization of clinical ATT protocols.

  13. Interleukin-7 Modulates Anti-Tumor CD8+ T Cell Responses via Its Action on Host Cells.

    Science.gov (United States)

    Deiser, Katrin; Stoycheva, Diana; Bank, Ute; Blankenstein, Thomas; Schüler, Thomas

    2016-01-01

    The adoptive transfer of antigen-specific CD8+ T cells is a promising approach for the treatment of chronic viral and malignant diseases. In order to improve adoptive T cell therapy (ATT) of cancer, recent strategies aim at the antibody-based blockade of immunosuppressive signaling pathways in CD8+ T cells. Alternatively, adjuvant effects of immunostimulatory cytokines might be exploited to improve therapeutic CD8+ T cell responses. For example, Interleukin-7 (IL-7) is a potent growth, activation and survival factor for CD8+ T cells that can be used to improve virus- and tumor-specific CD8+ T cell responses. Although direct IL-7 effects on CD8+ T cells were studied extensively in numerous models, the contribution of IL-7 receptor-competent (IL-7R+) host cells remained unclear. In the current study we provide evidence that CD8+ T cell-mediated tumor rejection in response to recombinant IL-7 (rIL-7) therapy is strictly dependent on IL-7R+ host cells. On the contrary, CD8+ T cell expansion is independent of host IL-7R expression. If, however, rIL-7 therapy and peptide vaccination are combined, host IL-7R signaling is crucial for CD8+ T cell expansion. Unexpectedly, maximum CD8+ T cell expansion relies mainly on IL-7R signaling in non-hematopoietic host cells, similar to the massive accumulation of dendritic cells and granulocytes. In summary, we provide evidence that IL-7R+ host cells are major targets of rIL-7 that modulate therapeutic CD8+ T cell responses and the outcome of rIL-7-assisted ATT. This knowledge may have important implications for the design and optimization of clinical ATT protocols.

  14. Adult T-cell leukemia: a review of epidemiological evidence

    Directory of Open Access Journals (Sweden)

    Masako eIwanaga

    2012-09-01

    Full Text Available Adult T-cell leukemia (ATL is an aggressive T-cell malignancy caused by human T-cell leukemia virus type I (HTLV-1 infection and often occurs in HTLV-1-endemic areas, such as southwestern Japan, the Caribbean islands, Central and South America, Intertropical Africa, and Middle East. To date, many epidemiological studies have been conducted to investigate the incidence of ATL among general population or HTLV-1 carriers and to identify a variety of laboratory, molecular, and host-specific markers to be possible predictive factors for developing ATL because HTLV-1 infection alone is not sufficient to develop ATL. This literature review focuses on the epidemiology of ATL and the risk factors for the development of ATL from HTLV-1 carriers, while keeping information on the epidemiology of HTLV-1 to a minimum. The main lines of epidemiological evidence are: (1 ATL occurs mostly in adults, at least 20–30 years after the HTLV-1 infection, (2 age at onset differs across geographic areas: the average age in the Central and South America (around 40 years old is younger than that in Japan (around 60 years old, (3 ATL occurs in those infected in childhood, but seldom occurs in those infected in adulthood, (4 male carriers have about a 3–5 fold higher risk of developing ATL than female, (5 the estimated life-time risk of developing ATL in HTLV-1 carriers is 6–7% for men and 2–3% for women in Japan, (6 a low anti-Tax reactivity, a high soluble interleukin-2 receptor level, a high anti-HTLV-1 titer, and high levels of circulating abnormal lymphocytes and white blood cell count are accepted risk factors for the development of ATL, and (7 a higher proviral load (more than 4 copies/100 peripheral blood mononuclear cells is an independent risk factor for progression of ATL. Nevertheless, the current epidemiological evidence is insufficient to fully understand the relationship between HTLV-1 infection and ATL. Further well-designed epidemiological studies

  15. 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.

  16. Group 2 innate lymphoid cells license dendritic cells to potentiate memory TH2 cell responses.

    Science.gov (United States)

    Halim, Timotheus Y F; Hwang, You Yi; Scanlon, Seth T; Zaghouani, Habib; Garbi, Natalio; Fallon, Padraic G; McKenzie, Andrew N J

    2016-01-01

    Rapid activation of memory CD4(+) T helper 2 (TH2) cells during allergic inflammation requires their recruitment into the affected tissue. Here we demonstrate that group 2 innate lymphoid (ILC2) cells have a crucial role in memory TH2 cell responses, with targeted depletion of ILC2 cells profoundly impairing TH2 cell localization to the lungs and skin of sensitized mice after allergen re-challenge. ILC2-derived interleukin 13 (IL-13) is critical for eliciting production of the TH2 cell-attracting chemokine CCL17 by IRF4(+)CD11b(+)CD103(-) dendritic cells (DCs). Consequently, the sentinel function of DCs is contingent on ILC2 cells for the generation of an efficient memory TH2 cell response. These results elucidate a key innate mechanism in the regulation of the immune memory response to allergens.

  17. Protective natural autoantibodies to apoptotic cells: evidence of convergent selection of recurrent innate-like clones.

    Science.gov (United States)

    Silverman, Gregg J

    2015-12-01

    During murine immune development, recurrent B cell clones arise in a predictable fashion. Among these B cells, an archetypical clonotypic set that recognizes phosphorylcholine (PC) antigens and produces anti-PC IgM, first implicated for roles in microbial protection, was later found to become expanded in hyperlipidemic mice and in response to an increased in vivo burden of apoptotic cells. These IgM natural antibodies can enhance clearance of damaged cells and induce intracellular blockade of inflammatory signaling cascades. In clinical populations, raised levels of anti-PC IgM correlate with protection from atherosclerosis and may also downmodulate the severity of autoimmune disease. Human anti-PC-producing clones without hypermutation have been isolated that can similarly discriminate apoptotic from healthy cells. An independent report on unrelated adults has described anti-PC-producing B cells with IgM genes that have conserved CDR3 motifs, similar to stereotypic clonal sets of B cell chronic lymphocytic leukemia. Taken together, emerging evidence suggests that, despite the capacity to form an effectively limitless range of Ig receptors, the human immune system may often recurrently generate lymphocytes expressing structurally convergent B cell receptors with protective and homeostatic roles.

  18. Cell-cycle radiation response: Role of intracellular factors

    Science.gov (United States)

    Blakely, E.; Chang, P.; Lommel, L.; Bjornstad, K.; Dixon, M.; Tobias, C.; Kumar, K.; Blakely, W. F.

    We have been studying variations of radiosensitivity and endogenous cellular factors during the course of progression through the human and hamster cell cycle. After exposure to low-LET radiations, the most radiosensitive cell stages are mitosis and the G1/S interface. The increased activity of a specific antioxidant enzyme such as superoxide dismutase in G1-phase, and the variations of endogenous thiols during cell division are thought to be intracellular factors of importance to the radiation survival response. These factors may contribute to modifying the age-dependent yield of lesions or more likely, to the efficiency of the repair processes. These molecular factors have been implicated in our cellular measurements of the larger values for the radiobiological oxygen effect late in the cycle compared to earlier cell ages. Low-LET radiation also delays progression through S phase which may allow more time for repair and hence contribute to radioresistance in late-S-phase. The cytoplasmic and intranuclear milieu of the cell appears to have less significant effects on lesions produced by high-LET radiation compared to those made by low-LET radiation. High-LET radiation fails to slow progression through S phase, and there is much less repair of lesions evident at all cell ages; however, high-LET particles cause a more profound block in G2 phase than that observed after low-LET radiation. Hazards posed by the interaction of damage from sequential doses of radiations of different qualities have been evaluated and are shown to lead to a cell-cycle-dependent enhancement of radiobiological effects. A summary comparison of various cell-cycle-dependent endpoints measured with low-or high-LET radiations is given and includes a discussion of the possible additional effects introduced by microgravity.

  19. Evidence for 'silicon' within the cell walls of suspension-cultured rice cells.

    Science.gov (United States)

    He, Congwu; Wang, Lijun; Liu, Jian; Liu, Xin; Li, Xiuli; Ma, Jie; Lin, Yongjun; Xu, Fangsen

    2013-11-01

    Despite the ubiquity and beneficial role of silicon (Si) in plant biology, structural and chemical mechanisms operating at the single-cell level have not been extensively studied. To obtain insights regarding the effect of Si on individual cells, we cultivated suspended rice (Oryza sativa) cells in the absence and presence of Si and analyzed single cells using a combination of physical techniques including atomic force microscopy (AFM). Si is naturally present as a constituent of the cell walls, where it is firmly bound to the cell wall matrix rather than occurring within intra- or extracellular silica deposition, as determined by using inductively coupled plasma mass spectrometry (ICP-MS) and X-ray photoelectron spectroscopy (XPS). This species of Si, linked with the cell wall matrix, improves the structural stability of cell walls during their expansion and subsequent cell division. Maintaining cell shape is thereby enhanced, which may be crucial for the function and survival of cells. This study provides further evidence that organosilicon is present in plant cell walls, which broadens our understanding of the chemical nature of 'anomalous Si' in plant biology.

  20. Modulation of T cell responses after cross-talk between antigen presenting cells and T cells: a give-and-take relationship.

    Science.gov (United States)

    Wauben, Marca H M; 't Hoen, Esther N M; Taams, Leonie S

    2003-01-01

    T cells presenting antigens in the context of MHC class II can induce anergy. In rat CD4+ T cell clones we have shown that depending on the depth of anergy other T cell responses can be inhibited in the presence of professional antigen presenting cells (APCs). This inhibition is cell-contact dependent, and APCs recovered from co-cultures with suppressive anergic T cells are modulated in their capacity to activate T cells. No changes in cell surface expression of MHC molecules, B7-1/B7-2, and OX40L were detected. Remarkably cell clusters formed by anergic T cells appeared to be more tight than clusters of activated T cells, and after fluorescent cell surface labelling of T cells, transfer of label was more profound in co-cultures of anergic T cells and APCs compared to activated T cells and APCs. Previously, it has been shown that activated T cells can absorb molecules from APCs in a unidirectional process. We now have evidence that also APCs can absorb cell surface molecules from T cells during APC-T cell co-cultures. We speculate that the quantity and quality of molecule reshuffling during cross-talk between T cells and APCs play a role in the regulation of the T cell response.

  1. 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-СІІ and PsHSP18.1-СІ, 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.

  2. 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)

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

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    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

  4. 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)

  5. Interleukin-21 triggers effector cell responses in the gut.

    Science.gov (United States)

    De Nitto, Daniela; Sarra, Massimiliano; Pallone, Francesco; Monteleone, Giovanni

    2010-08-07

    In the gut of patients with Crohn's disease and patients with ulcerative colitis, the major forms of inflammatory bowel diseases (IBD) in humans, the tissue-damaging immune response is mediated by an active cross-talk between immune and non-immune cells. Accumulating evidence indicates also that cytokines produced by these cells play a major role in initiating and shaping this pathologic process. One such cytokine seems to be interleukin (IL)-21, a member of the common gamma-chain-receptor family. IL-21 is produced in excess in the inflamed intestine of patients with IBD mostly by activated CD4+ T helper cells co-expressing interferon-gamma and follicular T helper cells. Moreover, both in vitro and in vivo studies indicate that excessive IL-21 production leads to the activation of multiple signaling pathways that expand and sustain the ongoing mucosal inflammation. In this article, we review the available data supporting the pathogenic role of IL-21 in IBD.

  6. Targeting the gut vascular endothelium induces gut effector CD8 T cell responses via cross-presentation by dendritic cells.

    Science.gov (United States)

    Bourges, Dorothee; Zhan, Yifan; Brady, Jamie L; Braley, Hal; Caminschi, Irina; Prato, Sandro; Villadangos, José A; Lew, Andrew M

    2007-11-01

    Systemic delivery of Ag usually induces poor mucosal immunity. To improve the CD8 T cell response at mucosal sites, we targeted the Ag to MAdCAM-1, a mucosal addressin cell adhesion molecule expressed mainly by high endothelial venules (HEV) in mesenteric lymph nodes (MLN) and Peyer's patches of gut-associated lymphoid tissue. When chemical conjugates of anti-MAdCAM-1 Ab and model Ag OVA were injected i.v., a greatly enhanced proliferative response of Ag-specific OT-I CD8 T cells was detected in MLN. This was preceded by prolonged accumulation, up to 2 wk, of the anti-MAdCAM OVA conjugate on HEV of Peyer's patches and MLN. In contrast, nontargeted OVA conjugate was very inefficient in inducing OT-I CD8 T cell proliferation in MLN and required at least 20-fold more Ag to induce a comparable response. In addition, MAdCAM targeting elicits an endogenous OVA-specific CD8 T cell response, evident by IFN-gamma production and target killing. Induced response offers protection against an OVA-expressing B cell lymphoma. We propose that the augmentation of gut CD8 T cell responses by MAdCAM targeting is due to both accumulation of Ag in the HEV and conversion of a soluble Ag to a cell-associated one, allowing cross-presentation by DCs.

  7. Local Microenvironment Controls the Compartmentalization of NK Cell Responses during Systemic Inflammation in Mice.

    Science.gov (United States)

    Rasid, Orhan; Ciulean, Ioana Sonya; Fitting, Catherine; Doyen, Noelle; Cavaillon, Jean-Marc

    2016-09-15

    Systemic inflammatory response syndrome is a whole-body reaction to a triggering insult that often results in life-threatening illness. Contributing to the development of this inflammatory cascade are numerous cellular partners, among which NK cells were shown to play a key role. Accumulating evidence points to organ-specific properties of systemic inflammation and NK cells. However, little is known about compartment-specific activation of NK cells during systemic inflammatory response syndrome or the relative contribution of NK cell-intrinsic properties and microenvironmental cues. In this study, we undertook a sequential characterization of NK responses in the spleen, lungs, bone marrow, peritoneum, and blood using a mouse model of endotoxemia. We report that, despite similar systemic dynamics of NK cell responses, expression of activation markers (CD69 and CD25) and effector molecules (IFN-γ, granzyme B, and IL-10) display organ-specific thresholds of maximum activation. Using adoptive transfers of spleen and lung NK cells, we found that these cells have the capacity to quickly adapt to a new environment and adjust their response levels to that of resident NK cells. This functional adaptation occurs without significant alterations in phenotype and independently of subpopulation-specific trafficking. Thus, using a dynamic in vivo-transfer system, to our knowledge our study is the first to report the compartmentalization of NK cells responses during systemic inflammation and to show that NK cell-intrinsic properties and microenvironmental cues are involved in this process, in a sequential manner.

  8. 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.

  9. The role of the cancer stem cell marker CD271 in DNA damage response and drug resistance of melanoma cells

    Science.gov (United States)

    Redmer, T; Walz, I; Klinger, B; Khouja, S; Welte, Y; Schäfer, R; Regenbrecht, C

    2017-01-01

    Several lines of evidence have suggested that stemness and acquired resistance to targeted inhibitors or chemotherapeutics are mechanistically linked. Here we observed high cell surface and total levels of nerve growth factor receptor/CD271, a marker of melanoma-initiating cells, in sub-populations of chemoresistant cell lines. CD271 expression was increased in drug-sensitive cells but not resistant cells in response to DNA-damaging chemotherapeutics etoposide, fotemustine and cisplatin. Comparative analysis of melanoma cells engineered to stably express CD271 or a targeting short hairpin RNA by expression profiling provided numerous genes regulated in a CD271-dependent manner. In-depth analysis of CD271-responsive genes uncovered the association of CD271 with regulation of DNA repair components. In addition, gene set enrichment analysis revealed enrichment of CD271-responsive genes in drug-resistant cells, among them DNA repair components. Moreover, our comparative screen identified the fibroblast growth factor 13 (FGF13) as a target of CD271, highly expressed in chemoresistant cells. Further we show that levels of CD271 determine drug response. Knock-down of CD271 in fotemustine-resistant cells decreased expression of FGF13 and at least partly restored sensitivity to fotemustine. Together, we demonstrate that expression of CD271 is responsible for genes associated with DNA repair and drug response. Further, we identified 110 CD271-responsive genes predominantly expressed in melanoma metastases, among them were NEK2, TOP2A and RAD51AP1 as potential drivers of melanoma metastasis. In addition, we provide mechanistic insight in the regulation of CD271 in response to drugs. We found that CD271 is potentially regulated by p53 and in turn is needed for a proper p53-dependent response to DNA-damaging drugs. In summary, we provide for the first time insight in a CD271-associated signaling network connecting CD271 with DNA repair, drug response and metastasis. PMID

  10. 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

  11. Multivalent proteoglycan modulation of FGF mitogenic responses in perivascular cells.

    Science.gov (United States)

    Cattaruzza, Sabrina; Ozerdem, Ugur; Denzel, Martin; Ranscht, Barbara; Bulian, Pietro; Cavallaro, Ugo; Zanocco, Daniela; Colombatti, Alfonso; Stallcup, William B; Perris, Roberto

    2013-04-01

    Sprouting of angiogenic perivascular cells is thought to be highly dependent upon autocrine and paracrine growth factor stimulation. Accordingly, we report that corneal angiogenesis induced by ectopic FGF implantation is strongly impaired in NG2/CSPG4 proteoglycan (PG) null mice known to harbour a putative deficit in pericyte proliferation/mobilization. Conversely, no significant differences were seen between wild type and knockout corneas when VEGF was used as an angiocrine factor. Perturbed responsiveness of NG2-deficient pericytes to paracrine and autocrine stimulation by several FGFs could be confirmed in cells isolated from NG2 null mice, while proliferation induced by other growth factors was equivalent in wild type and knockout cells. Identical results were obtained after siRNA-mediated knock-down of NG2 in human smooth muscle-like cell lines, as also demonstrated by the decreased levels of FGF receptor phosphorylation detected in these NG2 deprived cells. Binding assays with recombinant proteins and molecular interactions examined on live cells asserted that FGF-2 bound to NG2 in a glycosaminoglycan-independent, core protein-mediated manner and that the PG was alone capable of retaining FGF-2 on the cell membrane for subsequent receptor presentation. The use of dominant-negative mutant cells, engineered by combined transduction of NG2 deletion constructs and siRNA knock-down of the endogenous PG, allowed us to establish that the FGF co-receptor activity of NG2 is entirely mediated by its extracellular portion. In fact, forced overexpression of the NG2 ectodomain in human smooth muscle-like cells increased their FGF-2-induced mitosis and compensated for low levels of FGF receptor surface expression, in a manner equivalent to that produced by overexpression of the full-length NG2. Upon FGF binding, the cytoplasmic domain of NG2 is phosphorylated, but there is no evidence that this event elicits signal transductions that could bypass the FGFR-mediated ones

  12. Direct in vivo evidence for tumor propagation by glioblastoma cancer stem cells.

    Directory of Open Access Journals (Sweden)

    Justin D Lathia

    Full Text Available High-grade gliomas (World Health Organization grade III anaplastic astrocytoma and grade IV glioblastoma multiforme, the most prevalent primary malignant brain tumors, display a cellular hierarchy with self-renewing, tumorigenic cancer stem cells (CSCs at the apex. While the CSC hypothesis has been an attractive model to describe many aspects of tumor behavior, it remains controversial due to unresolved issues including the use of ex vivo analyses with differential growth conditions. A CSC population has been confirmed in malignant gliomas by preferential tumor formation from cells directly isolated from patient biopsy specimens. However, direct comparison of multiple tumor cell populations with analysis of the resulting phenotypes of each population within a representative tumor environment has not been clearly described. To directly test the relative tumorigenic potential of CSCs and non-stem tumor cells in the same microenvironment, we interrogated matched tumor populations purified from a primary human tumor transplanted into a xenograft mouse model and monitored competitive in vivo tumor growth studies using serial in vivo intravital microscopy. While CSCs were a small minority of the initial transplanted cancer cell population, the CSCs, not the non-stem tumor cells, drove tumor formation and yielded tumors displaying a cellular hierarchy. In the resulting tumors, a fraction of the initial transplanted CSCs maintained expression of stem cell and proliferation markers, which were significantly higher compared to the non-stem tumor cell population and demonstrated that CSCs generated cellular heterogeneity within the tumor. These head-to-head comparisons between matched CSCs and non-stem tumor cells provide the first functional evidence using live imaging that in the same microenvironment, CSCs more than non-stem tumor cells are responsible for tumor propagation, confirming the functional definition of a CSC.

  13. 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.

  14. The architects of B and T cell immune responses.

    Science.gov (United States)

    Lane, Peter J L

    2008-08-15

    Published work links adult lymphoid tissue-inducer cells (LTi) with T cell-dependent antibody responses. In this issue of Immunity, Tsuji et al. (2008) associate LTi with T cell-independent IgA antibody responses in the gut.

  15. Muscarinic responses of gastric parietal cells

    Energy Technology Data Exchange (ETDEWEB)

    Wilkes, J.M.; Kajimura, M.; Scott, D.R.; Hersey, S.J.; Sachs, G. (Department of Medicine, University of California, Los Angeles (United States))

    1991-06-01

    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.

  16. 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.

  17. 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.

  18. Cell-Cell Interactions Mediate the Response of Vascular Smooth Muscle Cells to Substrate Stiffness

    Science.gov (United States)

    Sazonova, Olga V.; Lee, Kristen L.; Isenberg, Brett C.; Rich, Celeste B.; Nugent, Matthew A.; Wong, Joyce Y.

    2011-01-01

    The vessel wall experiences progressive stiffening with age and the development of cardiovascular disease, which alters the micromechanical environment experienced by resident vascular smooth muscle cells (VSMCs). In vitro studies have shown that VSMCs are sensitive to substrate stiffness, but the exact molecular mechanisms of their response to stiffness remains unknown. Studies have also shown that cell-cell interactions can affect mechanotransduction at the cell-substrate interface. Using flexible substrates, we show that the expression of proteins associated with cell-matrix adhesion and cytoskeletal tension is regulated by substrate stiffness, and that an increase in cell density selectively attenuates some of these effects. We also show that cell-cell interactions exert a strong effect on cell morphology in a substrate-stiffness dependent manner. Collectively, the data suggest that as VSMCs form cell-cell contacts, substrate stiffness becomes a less potent regulator of focal adhesion signaling. This study provides insight into the mechanisms by which VSMCs respond to the mechanical environment of the blood vessel wall, and point to cell-cell interactions as critical mediators of VSMC response to vascular injury. PMID:21806930

  19. 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.…

  20. Evidence for the involvement of NOD2 in regulating colonic epithelial cell growth and survival

    Institute of Scientific and Technical Information of China (English)

    Sheena M Cruickshank; Louise Wakenshaw; John Cardone; Peter D Howdle; Peter J Murray; Simon R Carding

    2008-01-01

    AIM: To investigate the function of NOD2 in colonic epithelial cells (CEC).METHODS: A combination of in vivo and in vitro analyses of epithelial cell turnover in the presence and absence of a functional NOD2 protein and, in response to enteric Salmonella typhimurium infection, were used. shRNA interference was also used to investigate the consequences of knocking down NOD2 gene expression on the growth and survival of colorectal carcinoma cell lines.RESULTS: In the colonic mucosa the highest levels of NOD2 expression were in proliferating crypt epithelial cells. Muramyl dipeptide (MDP), that is recognized by NOD2, promoted CEC growth in vitro. By contrast, the growth of NOD2-deficient CECs was impaired. In vivo CEC proliferation was also reduced and apoptosis increased in Nod2-/- mice, which were also evident following enteric Salmonella infection. Furthermore, neutralization of NOD2 mRNA expression in human colonic carcinoma cells by shRNA interference resulted in decreased survival due to increased levels of apoptosis.CONCLUSION: These findings are consistent with the involvement of NOD2 protein in promoting CEC growth and survival. Defects in proliferation by CECs in cases of CD may contribute to the underlying pathology of disrupted intestinal homeostasis and excessive inflammation.

  1. Can neurological evidence help courts assess criminal responsibility? Lessons from law and neuroscience.

    Science.gov (United States)

    Aharoni, Eyal; Funk, Chadd; Sinnott-Armstrong, Walter; Gazzaniga, Michael

    2008-03-01

    Can neurological evidence help courts assess criminal responsibility? To answer this question, we must first specify legal criteria for criminal responsibility and then ask how neurological findings can be used to determine whether particular defendants meet those criteria. Cognitive neuroscience may speak to at least two familiar conditions of criminal responsibility: intention and sanity. Functional neuroimaging studies in motor planning, awareness of actions, agency, social contract reasoning, and theory of mind, among others, have recently targeted a small assortment of brain networks thought to be instrumental in such determinations. Advances in each of these areas bring specificity to the problems underlying the application of neuroscience to criminal law.

  2. Toll-like receptor 11-initiated innate immune response in male mouse germ cells.

    Science.gov (United States)

    Chen, Qiaoyuan; Zhu, Weiwei; Liu, Zhenghui; Yan, Keqin; Zhao, Shutao; Han, Daishu

    2014-02-01

    Toxoplasma gondii and uropathogenic Escherichia coli (UPEC) may infect the testis and impair testicular function. Mechanisms underlying testicular innate immune response to these two pathogens remain to be clarified. The present study examined the function of TLR11, which can be recognized by T. gondii-derived profilin and UPEC, in initiating innate immune response in male mouse germ cells. TLR11 is predominantly expressed in spermatids. Profilin and UPEC induced the expressions of different inflammatory cytokine profiles in the germ cells. In particular, profilin induced the expressions of macrophage chemotactic protein 1 (MCP1), interleukin 12 (IL12), and interferon gamma (IFNG) through nuclear factor KB (NFKB) activation. UPEC induced the expressions of MCP1, IL12, and IFNG, as well as tumor necrosis factor alpha (TNFA), IL6, and IFNB, through the activation of NFKB, IFN regulatory factor 3, and mitogen-activated protein kinases. Evidence showed that profilin induced the innate response in male germ cells through TLR11 signaling, and UPEC triggered the response through TLR11 and other TLR-signaling pathways. We also provided evidence that local injection of profilin or UPEC induces the innate immune response in the germ cells. Data describe TLR11-mediated innate immune function of male germ cells in response to T. gondii profilin and UPEC stimulations. This system may play a role in testicular defense against T. gondii and UPEC infections in mice.

  3. 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.

  4. Adult stem cell responses to nanostimuli

    OpenAIRE

    Tsimbouri, Penelope

    2015-01-01

    Adult or mesenchymal stem cells (MSCs) have been found in different tissues in the body, residing in stem cell microenvironments called “stem cell niches”. They play different roles but their main activity is to maintain tissue homeostasis and repair throughout the lifetime of an organism. Their ability to differentiate into different cell types makes them an ideal tool to study tissue development and to use them in cell-based therapies. This differentiation process is subject to both interna...

  5. Response-cost punishment with pigeons: further evidence of response suppression via token loss.

    Science.gov (United States)

    Raiff, Bethany R; Bullock, Christopher E; Hackenberg, Timothy D

    2008-02-01

    Four pigeons responded on a two-component multiple token-reinforcement schedule, in which tokens were produced according to a random-interval 30-sec schedule and exchanged according to a variable-ratio 4 schedule in both components. To assess the effects of contingent token loss, tokens were removed after every second response (i.e., fixed-ratio 2 loss) in one of the components. Response rates were selectively lower in the loss components relative to baseline (no-loss) conditions, as well as to the within-condition no-loss components. Response rates were decreased to a greater degree in the presence of tokens than in their absence. To control for the effects of changes in the density of token and food reinforcement, two parts consisted of additional conditions where food density and token loss were yoked to those in a previous loss condition. In the yoked-food condition, tokens were produced as usual in both components, but the overall density of food reinforcement in one of the components was yoked to that obtained during a previous token-loss condition. In the yoked token-loss condition, tokens were removed during one component of the multiple schedule at a rate that approximately matched the obtained rate of loss from a previous token-loss condition. Response rates in these yoked components were less affected than those in comparable loss components, despite similar densities of token, exchange, and food reinforcement. On the whole, the results support the conclusion that contingent token loss serves as an effective punisher with pigeons.

  6. Lactobacilli Modulate Natural Killer Cell Responses In Vitro

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    of certain lactic acid bacteria has been shown to increase in vivo NK cytotoxicity. Here, we investigated how human gut flora-derived lactobacilli affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human NK cells upon bacterial stimulation. CD3-CD56+ NK cells were isolated from...... the capacity to activate NK cells in vitro, in a monocyte dependent or independent way. Hence, the encounter of NK cells with lactic acid bacteria will affect NK cell activation. Such activation of NK cells may potentially skew an on-going or subsequent immune response towards a Th1 response........ The IFN-gamma concentration was measured by ELISA. Incubation of NK cells with a Lactobacillus acidophilus strain increased the proliferation of the NK cells and induced IFN-gamma production, both to levels comparable to PHA stimulation. The proliferative response was further enhanced with autologous...

  7. Cell type-specific responses of peripheral blood mononuclear cells to silver nanoparticles.

    Science.gov (United States)

    Greulich, C; Diendorf, J; Gessmann, J; Simon, T; Habijan, T; Eggeler, G; Schildhauer, T A; Epple, M; Köller, M

    2011-09-01

    Silver nanoparticles (Ag-NP) are increasingly used in biomedical applications because of their remarkable antimicrobial activity. In biomedicine, Ag-NP are coated onto or embedded in wound dressings, surgical instruments and bone substitute biomaterials, such as silver-containing calcium phosphate cements. Free Ag-NP and silver ions are released from these coatings or after the degradation of a biomaterial, and may come into close contact with blood cells. Despite the widespread use of Ag-NP as an antimicrobial agent, there is a serious lack of information on the biological effects of Ag-NP on human blood cells. In this study, the uptake of Ag-NP by peripheral monocytes and lymphocytes (T-cells) was analyzed, and the influence of nanosilver on cell biological functions (proliferation, the expression of adhesion molecules, cytokine release and the generation of reactive oxygen species) was studied. After cell culture in the presence of monodispersed Ag-NP (5-30μgml(-1) silver concentration), agglomerates of nanoparticles were detected within monocytes (CD14+) but not in T-cells (CD3+) by light microscopy, flow cytometry and combined focused ion beam/scanning electron microscopy. The uptake rate of nanoparticles was concentration dependent, and the silver agglomerates were typically found in the cytoplasm. Furthermore, a concentration-dependent activation (e.g. an increased expression of adhesion molecule CD54) of monocytes at Ag-NP concentrations of 10-15μgml(-1) was observed, and cytotoxicity of Ag-NP-treated monocytes was observed at Ag-NP levels of 25μgml(-1) and higher. However, no modulation of T-cell proliferation was observed in the presence of Ag-NP. Taken together, our results provide the first evidence for a cell-type-specific uptake of Ag-NP by peripheral blood mononuclear cells (PBMC) and the resultant cellular responses after exposure.

  8. Salmonella impairs CD8 T cell response through PD-1: PD-L axis.

    Science.gov (United States)

    López-Medina, Marcela; Carrillo-Martín, Ismael; Leyva-Rangel, Jessica; Alpuche-Aranda, Celia; Ortiz-Navarrete, Vianney

    2015-12-01

    We have shown that Salmonella remains for a long period of time within B cells, plasma cells, and bone marrow B cell precursors, which might allow persistence and dissemination of infection. Nonetheless, how infected cells evade CD8 T cell response has not been characterized. Evidence indicates that some pathogens exploit the PD-1: PD-L (PD-L1 and PD-L2) interaction to inhibit CD8 T cells response to contribute the chronicity of the infection. To determine whether the PD-1: PD-L axis plays a role during Salmonella infection; we evaluated PD-1 expression in antigen-specific CD8 T cells and PD-1 ligands in Salmonella-infected cells. Our results show that infected B cells and macrophages express continuously co-stimulatory (CD40, CD80, and CD86) and inhibitory molecules (PD-L1 and PD-L2) in early and late stages of chronic Salmonella infection, while antigen-specific CD8 T cells express in a sustained manner PD-1 in the late stages of infection. Blocking this axis restores the ability of the CD8 T cells to proliferate and eliminate primary infected APCs. Therefore, a continuous PD-1: PDL interaction might be a mechanism employed by Salmonella to negatively regulate Salmonella-specific CD8 T cell cytotoxic response in order to remain within the host for a long period of time.

  9. Evidence of Active Pro-Fibrotic Response in Blood of Patients with Cirrhosis.

    Directory of Open Access Journals (Sweden)

    Gloria Sanchez-Antolín

    Full Text Available The role of systemic immunity in the pathogenesis of cirrhosis is not fully understood. Analysis of transcriptomic profiles in blood is an easy approach to obtain a wide picture of immune response at the systemic level. We studied gene expression profiles in blood from thirty cirrhotic patients and compared them against those of eight healthy volunteers. Most of our patients were male [n = 21, 70%] in their middle ages [57.4 ± 6.8 yr]. Alcohol abuse was the most frequent cause of cirrhosis (n = 22, 73%. Eleven patients had hepatocellular carcinoma (36.7%. Eight patients suffered from hepatitis C virus infection (26.7%. We found a signature constituted by 3402 genes which were differentially expressed in patients compared to controls (2802 over-expressed and 600 under-expressed. Evaluation of this signature evidenced the existence of an active pro-fibrotic transcriptomic program in the cirrhotic patients, involving the [extra-cellular matrix (ECM-receptor interaction] & [TGF-beta signaling] pathways along with the [Cell adhesion molecules] pathway. This program coexists with alterations in pathways participating in [Glycine, serine and threonine metabolism], [Phenylalanine metabolism], [Tyrosine metabolism], [ABC transporters], [Purine metabolism], [Arachidonic acid metabolism]. In consequence, our results evidence the co-existence in blood of a genomic program mediating pro-fibrotic mechanisms and metabolic alterations in advanced cirrhosis. Monitoring expression levels of the genes involved in these programs could be of interest for predicting / monitoring cirrhosis evolution. These genes could constitute therapeutic targets in this disease.

  10. Fluoride inhibits the response of bone cells to mechanical loading

    NARCIS (Netherlands)

    Willems, H.M.E.; van den Heuvel, E.G.H.M.; Castelein, S.; Keverling Buisman, J.; Bronckers, A.L.J.J.; Bakker, A.D.; Klein-Nulend, J.

    2011-01-01

    The response of bone cells to mechanical loading is mediated by the cytoskeleton. Since the bone anabolic agent fluoride disrupts the cytoskeleton, we investigated whether fluoride affects the response of bone cells to mechanical loading, and whether this is cytoskeleton mediated. The mechano-respon

  11. 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.

  12. Two components in IOR: evidence for response bias and perceptual processing delays using the SAT methodology.

    Science.gov (United States)

    Zhao, Yuanyuan; Heinke, Dietmar; Ivanoff, Jason; Klein, Raymond M; Humphreys, Glyn W

    2011-10-01

    Inhibition of return (IOR) occurs when reaction times (RTs) are slowed to respond to a target that appears at a previously attended location. We used the speed-accuracy trade-off (SAT) procedure to obtain conjoint measures of IOR on sensitivity and processing speed by presenting targets at cued and uncued locations. The results showed that IOR is associated with both delays in processing speed and shifts in response criterion. When the target was briefly presented, the results supported a criterion shift account of IOR. However, when the target was presented until response, the evidence indicated that, in addition to a response bias effect, there was an increase in the minimal time required for information about the target to accumulate above chance level. A hybrid account of IOR is suggested that describes effects on both response bias and perceptual processing.

  13. 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.

  14. Ptch2 mediates the Shh response in Ptch1-/- cells.

    Science.gov (United States)

    Alfaro, Astrid C; Roberts, Brock; Kwong, Lina; Bijlsma, Maarten F; Roelink, Henk

    2014-09-01

    The Hedgehog (Hh) signaling response is regulated by the interaction of three key components that include the sonic hedgehog (Shh) ligand, its receptor patched 1 (Ptch1) and the pathway activator smoothened (Smo). Under the prevailing model of Shh pathway activation, the binding of Shh to Ptch1 (the key Shh receptor) results in the release of Ptch1-mediated inhibition of Smo, leading to Smo activation and subsequent cell-autonomous activation of the Shh response. Consistent with this model, Ptch1(-/-) cells show a strong upregulation of the Shh response. Our finding that this response can be inhibited by the Shh-blocking antibody 5E1 indicates that the Shh response in Ptch1(-/-) cells remains ligand dependent. Furthermore, we find that Shh induces a strong response in Ptch1(-/-);Shh(-/-) cells, and that Ptch1(-/-) fibroblasts retain their ability to migrate towards Shh, demonstrating that Ptch1(-/-) cells remain sensitive to Shh. Expression of a dominant-negative Ptch1 mutant in the developing chick neural tube had no effect on Shh-mediated patterning, but expression of a dominant-negative form of patched 2 (Ptch2) caused an activation of the Shh response. This indicates that, at early developmental stages, Ptch2 functions to suppress Shh signaling. We found that Ptch1(-/-);Ptch2(-/-) cells cannot further activate the Shh response, demonstrating that Ptch2 mediates the response to Shh in the absence of Ptch1.

  15. Frequency- dependent cell responses to an electromagnetic stimulus

    Science.gov (United States)

    Taghian, Toloo; Sheikh, Abdul; Narmoneva, Daria; Kogan, Andrei

    2013-03-01

    External electric field (EF) acting on cells in the ionic environment can trigger a variety of mechanical and chemical cell responses that regulate cell functions, such as adhesion, migration and cell signaling; thus manipulation of EF can be used in therapeutic applications. To optimize this process, realistic studies of EF interaction with cells are essential. We have developed a combined theoretical-experimental approach to study cell response to the external EF in the native configuration. The cell is modeled as a membrane-enclosed hemisphere which is cultured on a substrate and is surrounded by electrolyte. Maxwell's equations are solved numerically (ANSYS-HFSS) to obtain 3D EF distribution inside and near the cell subjected to an external EF. Theoretical results indicate that the cell response is frequency dependent, where at low frequency EF is excluded from the cell interior while EF penetration into the cell increases for higher frequencies. In both regimes the spatial distribution and strength of induced EF in membrane varies with frequency. Experimental results are consistent with theoretical predictions and show frequency-dependent cell response, including both membrane-initiated and intracellular pathway activation and growth factor release. The authors acknowledge the financial support from the NSF (DMR-1206784 & DMR-0804199 to AK); the NIH (1R21 DK078814-01A1 to DN) and the University of Cincinnati (Interdisciplinary Faculty Research Support Grant to DN and AK).

  16. Evidence of fast serotonin transmission in frog slowly adapting type 1 responses.

    Science.gov (United States)

    Press, Daniel; Mutlu, Sevinç; Güçlü, Burak

    2010-01-01

    The Merkel cell-neurite (MCN) complex generates slowly adapting type 1 (SA1) response when mechanically stimulated. Both serotonin (5-HT) and glutamate have been implicated in the generation of normal SA1 responses, but previous studies have been inconclusive as to what their roles are or how synaptic transmission occurs. In this study, excised dorsal skin patches from common water frogs (Rana ridibunda) were stimulated by von Frey hairs during perfusion in a tissue bath, and single-unit spike activity was recorded from SA1 fibres. Serotonin had no significant effect on the SA1 response at low (10 µM) concentration, significantly increased activity in a force-independent manner at 100 µM, but decreased activity with reduced responsiveness to force at 1 mM. Glutamate showed no effect on the responsiveness to force at 100 µM. MDL 72222 (100 µM), an ionotropic 5-HT3 receptor antagonist, completely abolished the responsiveness to force, suggesting that serotonin is released from Merkel cells as a result of mechanical stimulation, and activated 5-HT3 receptors on the neurite. The metabotropic 5-HT2 receptor antagonist, ketanserin, greatly reduced the SA1 fibre's responsiveness to force, as did the non-specific glutamate receptor antagonist, kynurenic acid. This supports a role for serotonin and glutamate as neuromodulators in the MCN complex, possibly by activation and/or inhibition of signalling cascades in the Merkel cell associated with vesicle release. Additionally, it was observed that SA1 responses contained a force-independent component, similar to a dynamic response observed during mechanical vibrations.

  17. 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.

  18. T cell immune responses in psoriasis.

    Directory of Open Access Journals (Sweden)

    Zohre Jadali

    2014-08-01

    Full Text Available A central role for T cells and their cytokines in the pathogenesis of psoriasis has been proposed; however, there are controversies over the details of this issue. The goal of this study is to summarise currently available data on the importance of T cells in psoriasis pathogenesis. A systematic review of the English medical literature was conducted by searching PubMed, Embase, ISI Web of Knowledge, and Iranian databases including Iranmedex, and SID for studies on associations between the involvement of T cell subsets and psoriasis. The results of the present study indicate that alterations in the number and function of different subsets of T-cells are associated with psoriasis. It appears that studies on T cell subsets contributed to understanding the immunopathogenesis of psoriasis. In addition, it may have provided novel therapeutic opportunities in ameliorating immunopathologies.

  19. The Role and Mechanisms of Double Negative Regulatory T Cells in the Suppression of Immune Responses

    Institute of Scientific and Technical Information of China (English)

    WenhaoChen; MeganS.Ford; KevinJ.Young; LiZhang

    2004-01-01

    Accumulating evidence has demonstrated that regulatory T (Treg) cells play an important role in the maintenance of immunologic self-tolerance and in down-regulating various immune responses. Thus, there has recently been an increasing interest in studying the biology of Treg cells as well as their potential application in treating immune diseases. Many types of Treg cell subsets have been reported in a variety of disease models.Among these subsets, αβ-TCR+CD3+CD4*CD8* double negative (DN) Treg cells are defined by their capability of inhibiting immune responses via directly killing effector T cells in an antigen specific fashion. Furthermore,DN Treg cells have been shown to develop regulatory activity after encountering specific antigens, partially mediated by the acquisition of MHC-peptide complexes from antigen presenting cells (APCs). The presentation of acquired alloantigens on DN T cells allows for the specific interaction between DN Treg cells and alloantigen reactive effector T cells. Once the DN Treg and target cells have come into contact, killing is then mediated by Fas/Fas-ligand interactions, and perhaps through other unidentified pathways. Further characterization of the functions, molecular expression and mechanisms of activation of DN Treg cells will help in the development of novel therapies to induce antigen specific tolerance to self and foreign antigens. Cellular & Molecular Immunology. 2004;1(5):328-335.

  20. The Role and Mechanisms of Double Negative Regulatory T Cells in the Suppression of Immune Responses

    Institute of Scientific and Technical Information of China (English)

    Wenhao Chen; Megan S. Ford; Kevin J. Young; Li Zhang

    2004-01-01

    Accumulating evidence has demonstrated that regulatory T (Treg) cells play an important role in the maintenance of immunologic self-tolerance and in down-regulating various immune responses. Thus, there has recently been an increasing interest in studying the biology of Treg cells as well as their potential application in treating immune diseases. Many types of Treg cell subsets have been reported in a variety of disease models.Among these subsets, αβ-TCR+CD3+CD4-CD8- double negative (DN) Treg cells are defined by their capability of inhibiting immune responses via directly killing effector T cells in an antigen specific fashion. Furthermore,DN Treg cells have been shown to develop regulatory activity after encountering specific antigens, partially mediated by the acquisition of MHC-peptide complexes from antigen presenting cells (APCs). The presentation of acquired alloantigens on DN T cells allows for the specific interaction between DN Treg cells and alloantigen reactive effector T cells. Once the DN Treg and target cells have come into contact, killing is then mediated by Fas/Fas-ligand interactions, and perhaps through other unidentified pathways. Further characterization of the functions, molecular expression and mechanisms of activation of DN Treg cells will help in the development of novel therapies to induce antigen specific tolerance to self and foreign antigens. Cellular & Molecular Immunology. 2004;1(5):328-335.

  1. 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.

  2. Competition for IL-2 between regulatory and effector T cells to chisel immune responses

    Directory of Open Access Journals (Sweden)

    Thomas eHöfer

    2012-09-01

    Full Text Available In this review we discuss how the competition for cytokines between different cells of the immune system can shape the system wide immune response. We focus on interleukin-2 (IL-2 secretion by activated effector T cells (Teff and on the competition for IL-2 consumption between Teff and regulatory T cells (Treg. We discuss the evidence for the mechanism in which the depletion of IL-2 by Treg cells would be sufficient to suppress an autoimmune response, yet not strong enough to prevent an immune response. We present quantitative estimations and summarize our modeling effort to show that the tug-of-war between Treg and Teff cells for IL-2 molecules can be won by Treg cells in the case of weak activation of Teff leading to the suppression of the immune response. Or, for strongly activated Teff cells, it can be won by Teff cells bringing about the activation of the whole adaptive immune system. Finally, we discuss some recent applications attempting to achieve clinical effects through the modulation of IL-2 consumption by Treg compartment.

  3. B-Cell Response during Protozoan Parasite Infections

    Directory of Open Access Journals (Sweden)

    María C. Amezcua Vesely

    2012-01-01

    Full Text Available In this review, we discuss how protozoan parasites alter immature and mature B cell compartment. B1 and marginal zone (MZ B cells, considered innate like B cells, are activated during protozoan parasite infections, and they generate short lived plasma cells providing a prompt antibody source. In addition, protozoan infections induce massive B cell response with polyclonal activation that leads to hypergammaglobulnemia with serum antibodies specific for the parasites and self and/or non related antigens. To protect themselves, the parasites have evolved unique ways to evade B cell immune responses inducing apoptosis of MZ and conventional mature B cells. As a consequence of the parasite induced-apoptosis, the early IgM response and an already establish humoral immunity are affected during the protozoan parasite infection. Moreover, some trypanosomatides trigger bone marrow immature B cell apoptosis, influencing the generation of new mature B cells. Simultaneously with their ability to release antibodies, B cells produce cytokines/quemokines that influence the characteristic of cellular immune response and consequently the progression of parasite infections.

  4. Evidence-Based Filters for Signal Detection: Application to Evoked Brain Responses

    CERN Document Server

    Mubeen, M Asim

    2011-01-01

    Template-based signal detection most often relies on computing a correlation, or a dot product, between an incoming data stream and a signal template. Such a correlation results in an ongoing estimate of the magnitude of the signal in the data stream. However, it does not directly indicate the presence or absence of the signal. The problem is really one of model-testing, and the relevant quantity is the Bayesian evidence (marginal likelihood) of the signal model. Given a signal template and an ongoing data stream, we have developed an evidence-based filter that computes the Bayesian evidence that a signal is present in the data. We demonstrate this algorithm by applying it to brain-machine interface (BMI) data obtained by recording human brain electrical activity, or electroencephalography (EEG). A very popular and effective paradigm in EEG-based BMI is based on the detection of the P300 evoked brain response which is generated in response to particular sensory stimuli. The goal is to detect the presence of a...

  5. Airway responses towards allergens - from the airway epithelium to T cells.

    Science.gov (United States)

    Papazian, D; Hansen, S; Würtzen, P A

    2015-08-01

    The prevalence of allergic diseases such as allergic rhinitis is increasing, affecting up to 30% of the human population worldwide. Allergic sensitization arises from complex interactions between environmental exposures and genetic susceptibility, resulting in inflammatory T helper 2 (Th2) cell-derived immune responses towards environmental allergens. Emerging evidence now suggests that an epithelial dysfunction, coupled with inherent properties of environmental allergens, can be responsible for the inflammatory responses towards allergens. Several epithelial-derived cytokines, such as thymic stromal lymphopoietin (TSLP), IL-25 and IL-33, influence tissue-resident dendritic cells (DCs) as well as Th2 effector cells. Exposure to environmental allergens does not elicit Th2 inflammatory responses or any clinical symptoms in nonatopic individuals, and recent findings suggest that a nondamaged, healthy epithelium lowers the DCs' ability to induce inflammatory T-cell responses towards allergens. The purpose of this review was to summarize the current knowledge on which signals from the airway epithelium, from first contact with inhaled allergens all the way to the ensuing Th2-cell responses, influence the pathology of allergic diseases.

  6. The Impact of Ly49-NK Cell-Dependent Recognition of MCMV Infection on Innate and Adaptive Immune Responses

    Directory of Open Access Journals (Sweden)

    Michal Pyzik

    2011-01-01

    Full Text Available Clinical and experimental data indicate that a subset of innate lymphocytes, natural killer (NK cells, plays a crucial role in the response against herpesviruses, especially cytomegaloviruses (CMV. Indeed, in mice, NK cells, due to the expression of germline encoded Ly49 receptors, possess multiple mechanisms to recognize CMV infection. Classically, this results in NK cell activation and the destruction of the infected cells. More recently, however, this unique host-pathogen interaction has permitted the discovery of novel aspects of NK cell biology, implicating them in the regulation of adaptive immune responses as well as in the development of immunological memory. Here, we will concisely review the newly acquired evidence pertaining to NK cell Ly49-dependent recognition of MCMV-infected cell and the ensuing NK cell regulatory responses.

  7. Raman scattering evidence of hydrohalite formation on frozen yeast cells

    CERN Document Server

    Okotrub, K A

    2012-01-01

    We studied yeast cells in physiological solution during freezing by Raman microspectroscopy technique. The purpose was to find out the origin of a sharp peak near ~3430 cm^-1 in Raman spectrum of frozen mammalian cells, observed earlier (J. Dong et al, Biophys. J., 99 (2010) 2453), which presumably could be used as an indicator of intracellar ice appearance. We have shown that this line (actually doublet of 3408 and 3425 cm^-1) corresponds to Raman spectrum of hydrohalite (NaCl-2H2O), which is formed as the result of the eutectic crystallization of the liquid solution around the cells. We also show that the spatial distribution of hydrohalite in the sample significantly depends on the cooling rate. At lower cooling rate (1{\\deg}C/min), products of eutectic crystallization form layer on the cell surface which thickness varies for different cells and can reach ~1 {\\mu}m in thickness. At higher cooling rate (20{\\deg}C/min), the hydrohalite distribution appears more homogeneous, in the sample, and the eutectic cr...

  8. Dendritic cells in hepatitis C virus infection: key players in the IFNL3-genotype response.

    Science.gov (United States)

    O'Connor, Kate S; George, Jacob; Booth, David; Ahlenstiel, Golo

    2014-12-21

    Recently, single nucleotide polymorphisms, in the vicinity of the interferon lambda 3 (IFNL3) gene have been identified as the strongest predictor of spontaneous and treatment induced clearance of hepatitis C virus (HCV) infection. Since then, increasing evidence has implicated the innate immune response in mediating the IFNL3 genotype effect. Dendritic cells (DCs) are key to the host immune response in HCV infection and their vital role in the IFNL3 genotype effect is emerging. Reports have identified subclasses of DCs, particularly myeloid DC2s and potentially plasmacytoid DCs as the major producers of IFNL3 in the setting of HCV infection. Given the complexities of dendritic cell biology and the conflicting current available data, this review aims to summarize what is currently known regarding the role of dendritic cells in HCV infection and to place it into context of what is know about lambda interferons and dendritic cells in general.

  9. Cell-mediated responses of immunized vervet monkeys to defined Leishmania T-cell epitopes.

    OpenAIRE

    Curry, A J; Jardim, A; Olobo, J.O.; Olafson, R W

    1994-01-01

    A population of vervet monkeys was immunized with killed parasites and infected with Leishmania major promastigotes either by needle or by infected-fly bite. The responses of recovered monkeys to mitogens, killed parasites, and molecularly defined T-cell epitopes were then compared with those of control animals. Peripheral blood mononuclear cells (PBMC) from both naive and recovered animals proliferated strongly in response to both B- and T-cell mitogens, although the responses of the recover...

  10. Asymmetry in stimulus and response conflict processing across the adult lifespan: ERP and EMG evidence.

    Science.gov (United States)

    Killikelly, Clare; Szűcs, Dénes

    2013-01-01

    Several studies have shown that conflict processing improves from childhood to adulthood and declines from adulthood to old age. However the neural mechanisms underlying this lifespan asymmetry were previously unexplored. We combined event-related potentials (ERPs) and electromyography (EMG) to examine lifespan changes in stimulus and response conflict processing using a modified Stroop task. We used a Stroop task that a priori dissociated stimulus and response conflict. Delayed P3b latency and increased amplitude revealed that middle age adults have a deficit in stimulus processing. Additionally a sustained P3a across frontal and central electrodes occurred only in middle age adults indicating the recruitment of frontal activity. Conversely, decreased lateralized readiness potential (LRP) amplitude and increased EMG activity in the incorrect hand in adolescents reveal protracted development of response processing into late adolescence. The N450, a measure of conflict processing, was found to be sensitive to both stimulus and response conflict. Altogether these results provide evidence for asymmetrical differences in stimulus and response conflict processing across adolescence, young adulthood and middle age.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kuchma, Oleksandra, E-mail: oleksandra.kuchma@googlemail.com [Forest Genetics and Forest Tree Breeding, Buesgen Institute, Georg-August University Goettingen, Buesgenweg 2, Goettingen 37077 (Germany); Finkeldey, Reiner, E-mail: rfinkel@gwdg.de [Forest Genetics and Forest Tree Breeding, Buesgen Institute, Georg-August University Goettingen, Buesgenweg 2, Goettingen 37077 (Germany)

    2011-06-15

    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.

  12. Evidence for a Melanin Cell Wall Component in Pneumocystis carinii

    OpenAIRE

    Icenhour, Crystal R.; Kottom, Theodore J.; Limper, Andrew H

    2003-01-01

    Fluorescein isothiocyanate-labeled monoclonal antibodies specific for fungal melanin were used in this study to visualize melanin-like components of the Pneumocystis carinii cell wall. A colorimetric enzyme assay confirmed these findings. This is the first report of melanin-like pigments in Pneumocystis.

  13. Circadian control of antigen-specific T cell responses

    Directory of Open Access Journals (Sweden)

    Nobis CC

    2016-09-01

    Full Text Available Chloé C Nobis,1–3 Nathalie Labrecque,2–4 Nicolas Cermakian1,5–8 1Douglas Mental Health University Institute, 2Maisonneuve-Rosemont Hospital Research Centre, 3Department of Microbiology, Infectious Diseases and Immunology, 4Department of Medicine, University of Montreal, 5Department of Psychiatry, 6Department of Microbiology and Immunology, 7Department of Neurology and Neurosurgery, 8Department of Physiology, McGill University, Montreal, QC, Canada Abstract: The immune system is composed of two arms, the innate and the adaptive immunity. While the innate response constitutes the first line of defense and is not specific for a particular pathogen, the adaptive response is highly specific and allows for long-term memory of the pathogen encounter. T lymphocytes (or T cells are central players in the adaptive immune response. Various aspects of T cell functions vary according to the time of day. Circadian clocks located in most tissues and cell types generate 24-hour rhythms of various physiological processes. These clocks are based on a set of clock genes, and this timing mechanism controls rhythmically the expression of numerous other genes. Clock genes are expressed in cells of the immune system, including T cells. In this review, we provide an overview of the circadian control of the adaptive immune response, with emphasis on T cells, including their development, trafficking, response to antigen, and effector functions. Keywords: circadian clock, adaptive immune response, T lymphocyte, antigen, cytokine, proliferation

  14. Antibody-Independent Function of Human B Cells Contributes to Antifungal T Cell Responses.

    Science.gov (United States)

    Li, Rui; Rezk, Ayman; Li, Hulun; Gommerman, Jennifer L; Prat, Alexandre; Bar-Or, Amit

    2017-03-08

    Fungal infections (e.g., Candida albicans) can manifest as serious medical illnesses, especially in the elderly and immune-compromised hosts. T cells are important for Candida control. Whether and how B cells are involved in antifungal immunity has been less clear. Although patients with agammaglobulinemia exhibit normal antifungal immunity, increased fungal infections are reported following B cell-depleting therapy, together pointing to Ab-independent roles of B cells in controlling such infections. To test how human B cells may contribute to fungal-associated human T cell responses, we developed a novel Ag-specific human T cell/B cell in vitro coculture system and found that human B cells could induce C. albicans-associated, MHC class II-restricted responses of naive T cells. Activated B cells significantly enhanced C. albicans-mediated Th1 and Th17 T cell responses, which were both strongly induced by CD80/CD86 costimulation. IL-6(+)GM-CSF(+) B cells were the major responding B cell subpopulation to C. albicans and provided efficient costimulatory signals to the T cells. In vivo B cell depletion in humans resulted in reduced C. albicans-associated T responses. Of note, the decreased Th17, but not Th1, responses could be reversed by soluble factors from B cells prior to depletion, in an IL-6-dependent manner. Taken together, our results implicate an Ab-independent cytokine-defined B cell role in human antifungal T cell responses. These findings may be particularly relevant given the prospects of chronic B cell depletion therapy use in lymphoma and autoimmune disease, as patients age and are exposed to serial combination therapies.

  15. 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.

  16. Differential T helper cell response in tuberculous pleuritis

    Directory of Open Access Journals (Sweden)

    Prabha C

    2007-01-01

    Full Text Available Purpose: This study was conducted to understand the in vivo and in vitro immune responses and to find whether there exists any difference in the systemic and localized immune responses in tuberculous pleuritis. Methods: The in vivo levels of IFN-γ and IL-4 were compared in plasma (BL and pleural fluid (PF of 47 tuberculous (TB and 31 nontuberculous pleuritis (Non-TB patients. In vitro cytokine response to various mycobacterial antigens was studied in 19 TB patients by ELISA . Both ex vivo and in vitro cytokine responses were further ascertained by intracellular cytokine staining on purified CD4+ T cells from pleural fluid mononuclear cells (PFMC of 10 TB patients. Results: The ex vivo results showed a significant increase in IFN-γ levels and higher IFN-γ + T cells in PF. On the other hand, in vitro results showed simultaneous increase in both IFN-γ and IL-4 levels in the supernatants of antigen stimulated PFMC. Similarly antigen specific increase was observed in both IFN-γ + and IL-4+ T cells in all cultured conditions. However, the percentile increase was more in IL-4 secreting T cells, significant for PPD stimulation ( P < 0.05, indicating that in vitro cellular response was dominated by Th2 type. Conclusions: These results showed a differential T-helper response in TB pleuritis suggestive of predominant Th1 in vivo and mixed response (Th1 and Th2 under in vitro conditions.

  17. The T Cell Response to Actinobacillus actinomycetemcomitans

    Science.gov (United States)

    2006-05-01

    disease (11). Other clinical features of the disease include deep pain on mastication, first molar mobility, distolabial migration of maxillary incisors...transformed into one shot chemically competent E. coli TOP -10 (InVitrogen). 40 .tl from each transformation was grown at 37°C overnight on LB plates...5. Peripheral Blood Mononuclear Cells (PBMCs) isolation The 13 ml vacutainer with SST Gel and Clot Activator, or "Tiger Top ," was centrifuged at 3800

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

    Science.gov (United States)

    Pennisi, C. P.; Sevcencu, C.; Dolatshahi-Pirouz, A.; Foss, M.; Lundsgaard Hansen, J.; Nylandsted Larsen, A.; Zachar, V.; Besenbacher, F.; Yoshida, K.

    2009-09-01

    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.

  19. Evidence for adaptive evolution of low-temperature stress response genes in a Pooideae grass ancestor

    DEFF Research Database (Denmark)

    Vigeland, Magnus D; Spannagl, Manuel; Asp, Torben;

    2013-01-01

    evolution of LTI pathway genes was important for Pooideae evolution. Substitution rates and signatures of positive selection were analyzed using 4330 gene trees including three warm climate-adapted species (maize (Zea mays), sorghum (Sorghum bicolor), and rice (Oryza sativa)) and five temperate Pooideae...... of positive selection were significantly stronger in LTI trees after the rice and Pooideae split but before the Brachypodium divergence (P ... evidence for a link between adaptation to cold habitats and adaptive evolution of LTI stress responses in early Pooideae evolution and shed light on a poorly understood chapter in the evolutionary history of some of the world's most important temperate crops...

  20. AXL as a modulator of sunitinib response in glioblastoma cell lines

    OpenAIRE

    Martinho, Olga Catarina Lopes; Zucca, Luís Eduardo; Reis,R.M.

    2015-01-01

    Receptor tyrosine kinase (RTK) targeted therapy has been explored for glioblastoma treatment. However, it is unclear which RTK inhibitors are the most effective and there are no predictive biomarkers available. We recently identified the RTK AXL as a putative target for the pan-RTK inhibitors cediranib and sunitinib, which are under clinical trials for glioblastoma patients. Here, we provide evidence that AXL activity can modulate sunitinib response in glioblastoma cell lines. We found that A...

  1. 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.

  2. New insights into the unfolded protein response in stem cells.

    Science.gov (United States)

    Yang, Yanzhou; Cheung, Hoi Hung; Tu, JiaJie; Miu, Kai Kei; Chan, Wai Yee

    2016-08-16

    The unfolded protein response (UPR) is an evolutionarily conserved adaptive mechanism to increase cell survival under endoplasmic reticulum (ER) stress conditions. The UPR is critical for maintaining cell homeostasis under physiological and pathological conditions. The vital functions of the UPR in development, metabolism and immunity have been demonstrated in several cell types. UPR dysfunction activates a variety of pathologies, including cancer, inflammation, neurodegenerative disease, metabolic disease and immune disease. Stem cells with the special ability to self-renew and differentiate into various somatic cells have been demonstrated to be present in multiple tissues. These cells are involved in development, tissue renewal and certain disease processes. Although the role and regulation of the UPR in somatic cells has been widely reported, the function of the UPR in stem cells is not fully known, and the roles and functions of the UPR are dependent on the stem cell type. Therefore, in this article, the potential significances of the UPR in stem cells, including embryonic stem cells, tissue stem cells, cancer stem cells and induced pluripotent cells, are comprehensively reviewed. This review aims to provide novel insights regarding the mechanisms associated with stem cell differentiation and cancer pathology.

  3. Responses of retinal ganglion cells to extracellular electrical stimulation, from single cell to population: model-based analysis.

    Directory of Open Access Journals (Sweden)

    David Tsai

    Full Text Available Retinal ganglion cells (RGCs, which survive in large numbers following neurodegenerative diseases, could be stimulated with extracellular electric pulses to elicit artificial percepts. How do the RGCs respond to electrical stimulation at the sub-cellular level under different stimulus configurations, and how does this influence the whole-cell response? At the population level, why have experiments yielded conflicting evidence regarding the extent of passing axon activation? We addressed these questions through simulations of morphologically and biophysically detailed computational RGC models on high performance computing clusters. We conducted the analyses on both large-field RGCs and small-field midget RGCs. The latter neurons are unique to primates. We found that at the single cell level the electric potential gradient in conjunction with neuronal element excitability, rather than the electrode center location per se, determined the response threshold and latency. In addition, stimulus positioning strongly influenced the location of RGC response initiation and subsequent activity propagation through the cellular structure. These findings were robust with respect to inhomogeneous tissue resistivity perpendicular to the electrode plane. At the population level, RGC cellular structures gave rise to low threshold hotspots, which limited axonal and multi-cell activation with threshold stimuli. Finally, due to variations in neuronal element excitability over space, following supra-threshold stimulation some locations favored localized activation of multiple cells, while others favored axonal activation of cells over extended space.

  4. 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…

  5. The Role of Plasmacytoid Dendritic Cells in Innate and Adaptive Immune Responses against Alpha Herpes Virus Infections

    Directory of Open Access Journals (Sweden)

    Philipp Schuster

    2011-01-01

    Full Text Available In 1999, two independent groups identified plasmacytoid dendritic cells (PDC as major type I interferon- (IFN- producing cells in the blood. Since then, evidence is accumulating that PDC are a multifunctional cell population effectively coordinating innate and adaptive immune responses. This paper focuses on the role of different immune cells and their interactions in the surveillance of alpha herpes virus infections, summarizes current knowledge on PDC surface receptors and their role in direct cell-cell contacts, and develops a risk factor model for the clinical implications of herpes simplex and varicella zoster virus reactivation. Data from studies involving knockout mice and cell-depletion experiments as well as human studies converge into a “spider web”, in which the direct and indirect crosstalk between many cell populations tightly controls acute, latent, and recurrent alpha herpes virus infections. Notably, cells involved in innate immune regulations appear to shape adaptive immune responses more extensively than previously thought.

  6. 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...

  7. Assessing T-cell responses in anticancer immunotherapy

    Science.gov (United States)

    Escors, David; Liechtenstein, Therese; Perez-Janices, Noemi; Schwarze, Julia; Dufait, Ines; Goyvaerts, Cleo; Lanna, Alessio; Arce, Frederick; Blanco-Luquin, Idoia; Kochan, Grazyna; Guerrero-Setas, David; Breckpot, Karine

    2013-01-01

    Since dendritic cells operate as professional antigen-presenting cells (APCs) and hence are capable of jumpstarting the immune system, they have been exploited to develop a variety of immunotherapeutic regimens against cancer. In the few past years, myeloid-derived suppressor cells (MDSCs) have been shown to mediate robust immunosuppressive functions, thereby inhibiting tumor-targeting immune responses. Thus, we propose that the immunomodulatory activity of MDSCs should be carefully considered for the development of efficient anticancer immunotherapies. PMID:24244902

  8. 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.

  9. Is there a role for mammary stem cells in inflammatory breast carcinoma?: a review of evidence from cell line, animal model, and human tissue sample experiments.

    Science.gov (United States)

    Van Laere, Steven; Limame, Ridha; Van Marck, Eric A; Vermeulen, Peter B; Dirix, Luc Y

    2010-06-01

    Stem cells are pluripotent cells, with a large replicative potential, which perform normal physiological functions such as tissue renewal and damage repair. However, because of their long lifespan and high replicative potential, stem cells are ideal targets to accumulate multiple mutations. Therefore, they can be regarded as being responsible for the initiation of tumor formation. In the past, numerous studies have shown that the presence of an elaborate stem cell compartment within a tumor is associated with aggressive tumor cell behavior, frequent formation of metastases, resistance to therapy, and poor patient survival. From this perspective, tumors from patients with inflammatory breast cancer (IBC), an aggressive breast cancer subtype with a dismal clinical course, are most likely to be associated with stem cell biology. To date, this hypothesis is corroborated by evidence resulting from in vitro and in vivo experiments. Both gene and microRNA expression profiles highlighted several stem cell-specific signal transduction pathways that are hyperactivated in IBC. Also, these stem cell-specific signal transduction pathways seem to converge in the activation of nuclear factor-kappa B, a molecular hallmark of IBC, and induction of epithelial-to-mesenchymal transition. Recently, the latter mechanism was identified as a prerequisite for the induction of stem cell characteristics in breast cancer cells.

  10. Immune response in virus model structured by cell infection-age.

    Science.gov (United States)

    Browne, Cameron

    2016-10-01

    This paper concerns modeling the coupled within-host population dynamics of virus and CTL (Cytotoxic T Lymphocyte) immune response. There is substantial evidence that the CTL immune response plays a crucial role in controlling HIV in infected patients. Recent experimental studies have demonstrated that certain CTL variants can recognize HIV infected cells early in the infected cell lifecycle before viral production, while other CTLs only detect viral proteins (epitopes) presented on the surface of infected cells after viral production. The kinetics of epitope presentation and immune recognition can impact the efficacy of the immune response. We extend previous virus models to include cell infection-age structure in the infected cell compartment and immune response killing/activation rates of a PDE-ODE system. We characterize solutions to our system utilizing semigroup theory, determine equilibria and reproduction numbers, and prove stability and persistence results. Numerical simulations show that ' early immune recognition' precipitates both enhanced viral control and sustained oscillations via a Hopf bifurcation. In addition to inducing oscillatory dynamics, considering immune process rates to be functions of cell infection-age can also lead to coexistence of multiple distinct immune effector populations.

  11. 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.

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

    Science.gov (United States)

    Sandalova, Elena; Laccabue, Diletta; Boni, Carolina; Tan, Anthony T; Fink, Katja; Ooi, Eng Eong; Chua, Robert; Shafaeddin Schreve, Bahar; Ferrari, Carlo; Bertoletti, Antonio

    2010-08-19

    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.

  13. 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 prosecutio

  14. Prophylactic Platelets in Dengue: Survey Responses Highlight Lack of an Evidence Base

    Science.gov (United States)

    Whitehorn, James; Roche, Rosmari Rodriguez; Guzman, Maria G.; Martinez, Eric; Villamil Gomez, Wilmar; Nainggolan, Leonard; Laksono, Ida Safitri; Mishra, Ajay; Lum, Lucy; Faiz, Abul; Sall, Amadou; Dawurung, Joshua; Borges, Alvaro; Leo, Yee-Sin; Blumberg, Lucille; Bausch, Daniel G.; Kroeger, Axel; Horstick, Olaf; Thwaites, Guy; Wertheim, Heiman; Larsson, Mattias; Hien, Tran Tinh; Peeling, Rosanna; Wills, Bridget; Simmons, Cameron; Farrar, Jeremy

    2012-01-01

    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. PMID:22745847

  15. 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.

  16. The roles and responsibilities of physicians in patients' decisions about unproven stem cell therapies.

    Science.gov (United States)

    Levine, Aaron D; Wolf, Leslie E

    2012-01-01

    Capitalizing on the hype surrounding stem cell research, numerous clinics around the world offer "stem cell therapies" for a variety of medical conditions. Despite questions about the safety and efficacy of these interventions, anecdotal evidence suggests a relatively large number of patients are traveling to receive these unproven treatments - a practice called "stem cell tourism." Because these unproven treatments pose risks to individual patients and to legitimate translational stem cell research, stem cell tourism has generated substantial policy concern and inspired attempts to reduce these risks through the development of guidelines for patients and medical practitioners. This paper examines the roles and responsibilities of physicians in patients' home countries with respect to patients' decisions to try unproven stem cell therapies abroad. Specifically, it examines professional guidance from two organizations - the American Medical Association and the International Society for Stem Cell Research - and assesses physicians' professional and legal obligations to patients considering unproven stem cell therapies. Then, drawing on qualitative interviews conducted with patients who traveled abroad for unproven stem cell treatments, it explores the roles that physicians actually play in patients' decisions and compares these actual roles with their professional and legal responsibilities. The paper concludes with a discussion of strategies to help improve the guidance physicians provide to patients considering unproven treatments.

  17. Apoptotic neurons induce proliferative responses of progenitor cells in the postnatal neocortex.

    Science.gov (United States)

    Petrenko, Volodymyr; Mihhailova, Jevgenia; Salmon, Patrick; Kiss, Jozsef Z

    2015-11-01

    Apoptotic cell death is the leading cause of neuronal loss after neonatal brain injury. Little is known about the intrinsic capacity of the immature cerebral cortex for replacing dead cells. Here we test the hypothesis that neuronal apoptosis is able to trigger compensatory proliferation in surrounding cells. In order to establish a "pure" apoptotic cell death model and to avoid the confounding effects of broken blood-brain barrier and inflammatory reactions, we used a diphtheria toxin (DT) and diphtheria toxin receptor (DTR) system to induce ablation of layer IV neurons in the rodent somatosensory cortex during the early postnatal period. We found that DT-triggered apoptosis is a slowly progressing event lasting about for 7 days. While dying cells expressed the morphological features of apoptosis, we could not detect immunoreactivity for activated caspase-3 in these cells. Microglia activation and proliferation represented the earliest cellular responses to apoptotic cell death. In addition, we found that induced apoptosis triggered a massive proliferation of undifferentiated progenitor cell pool including Sox2 as well as NG2 cells. The default differentiation pattern of proliferating progenitors appears to be the glial phenotype; we could not find evidence for newly generated neurons in response to apoptotic neuronal death. These results suggest that mitotically active progenitor populations are intrinsically capable to contribute to the repair process of injured cortical tissue and may represent a potential target for neuronal replacement strategies.

  18. Transmembrane Protein 184A Is a Receptor Required for Vascular Smooth Muscle Cell Responses to Heparin.

    Science.gov (United States)

    Pugh, Raymond J; Slee, Joshua B; Farwell, Sara Lynn N; Li, Yaqiu; Barthol, Trista; Patton, Walter A; Lowe-Krentz, Linda J

    2016-03-01

    Vascular cell responses to exogenous heparin have been documented to include decreased vascular smooth muscle cell proliferation following decreased ERK pathway signaling. However, the molecular mechanism(s) by which heparin interacts with cells to induce those responses has remained unclear. Previously characterized monoclonal antibodies that block heparin binding to vascular cells have been found to mimic heparin effects. In this study, those antibodies were employed to isolate a heparin binding protein. MALDI mass spectrometry data provide evidence that the protein isolated is transmembrane protein 184A (TMEM184A). Commercial antibodies against three separate regions of the TMEM184A human protein were used to identify the TMEM184A protein in vascular smooth muscle cells and endothelial cells. A GFP-TMEM184A construct was employed to determine colocalization with heparin after endocytosis. Knockdown of TMEM184A eliminated the physiological responses to heparin, including effects on ERK pathway activity and BrdU incorporation. Isolated GFP-TMEM184A binds heparin, and overexpression results in additional heparin uptake. Together, these data support the identification of TMEM184A as a heparin receptor in vascular cells.

  19. Prostate progenitor cells proliferate in response to castration

    Directory of Open Access Journals (Sweden)

    Xudong Shi

    2014-07-01

    Full Text Available Androgen-deprivation is a mainstay of therapy for advanced prostate cancer but tumor regression is usually incomplete and temporary because of androgen-independent cells in the tumor. It has been speculated that these tumor cells resemble the stem/progenitor cells of the normal prostate. The purpose of this study was to examine the response of slow-cycling progenitor cells in the adult mouse prostate to castration. Proliferating cells in the E16 urogenital sinus were pulse labeled by BrdU administration or by doxycycline-controlled labeling of the histone-H2B GFP mouse. A small population of labeled epithelial cells in the adult prostate localized at the junction of the prostatic ducts and urethra. Fluorescence-activated cell sorting (FACS showed that GFP label-retaining cells were enriched for cells co-expressing stem cell markers Sca-1, CD133, CD44 and CD117 (4- marker cells; 60-fold enrichment. FACS showed, additionally, that 4-marker cells were androgen receptor positive. Castration induced proliferation and dispersal of E16 labeled cells into more distal ductal segments. When naïve adult mice were administered BrdU daily for 2 weeks after castration, 16% of 4-marker cells exhibited BrdU label in contrast to only 6% of all epithelial cells (P < 0.01. In sham-castrated controls less than 4% of 4-marker cells were BrdU labeled (P < 0.01. The unexpected and admittedly counter-intuitive finding that castration induced progenitor cell proliferation suggests that androgen deprivation therapy in men with advanced prostate cancer could not only exert pleiotrophic effects on tumor sub-populations but may induce inadvertent expansion of tumor stem cells.

  20. 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.

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

    Science.gov (United States)

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

    2015-12-10

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

  2. Radiation response of mesenchymal stem cells derived from bone marrow and human pluripotent stem cells

    OpenAIRE

    Islam, Mohammad S; Stemig, Melissa E.; Takahashi, Yutaka; Hui, Susanta K.

    2014-01-01

    Mesenchymal stem cells (MSCs) isolated from human pluripotent stem cells are comparable with bone marrow-derived MSCs in their function and immunophenotype. The purpose of this exploratory study was comparative evaluation of the radiation responses of mesenchymal stem cells derived from bone marrow- (BMMSCs) and from human embryonic stem cells (hESMSCs). BMMSCs and hESMSCs were irradiated at 0 Gy (control) to 16 Gy using a linear accelerator commonly used for cancer treatment. Cells were harv...

  3. Axitinib induces DNA damage response leading to senescence, mitotic catastrophe, and increased NK cell recognition in human renal carcinoma cells.

    Science.gov (United States)

    Morelli, Maria Beatrice; Amantini, Consuelo; Santoni, Matteo; Soriani, Alessandra; Nabissi, Massimo; Cardinali, Claudio; Santoni, Angela; Santoni, Giorgio

    2015-11-03

    Tyrosine kinase inhibitors (TKIs) including axitinib have been introduced in the treatment of renal cell carcinoma (RCC) because of their anti-angiogenic properties. However, no evidence are presently available on a direct cytotoxic anti-tumor activity of axitinib in RCC.Herein we reported by western blot analysis that axitinib treatment induces a DNA damage response (DDR) initially characterized by γ-H2AX phosphorylation and Chk1 kinase activation and at later time points by p21 overexpression in A-498 and Caki-2 RCC cells although with a different potency. Analysis by immunocytochemistry for the presence of 8-oxo-7,8-dihydro-2'-deoxyguanosine in cellular DNA and flow cytometry using the redox-sensitive fluorescent dye DCFDA, demonstrated that DDR response is accompanied by the presence of oxidative DNA damage and reactive oxygen species (ROS) generation. This response leads to G2/M cell cycle arrest and induces a senescent-like phenotype accompanied by enlargement of cells and increased senescence-associated β-galactosidase activity, which are abrogated by N-acetyl cysteine (NAC) pre-treatment. In addition, axitinib-treated cells undergo to cell death through mitotic catastrophe characterized by micronucleation and abnormal microtubule assembly as assessed by fluorescence microscopy.On the other hand, axitinib, through the DDR induction, is also able to increase the surface NKG2D ligand expression. Accordingly, drug treatment promotes NK cell recognition and degranulation in A-498 RCC cells in a ROS-dependent manner.Collectively, our results indicate that both cytotoxic and immunomodulatory effects on RCC cells can contribute to axitinib anti-tumor activity.

  4. Microphysical and macrophysical responses of marine stratocumulus polluted by underlying ships: Evidence of cloud deepening

    Science.gov (United States)

    Christensen, Matthew W.; Stephens, Graeme L.

    2011-02-01

    Ship tracks observed by the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) were analyzed to determine the extent to which aerosol plumes from ships passing below marine stratocumulus alter the microphysical and macrophysical properties of the clouds. Moderate Resolution Imaging Spectroradiometer (MODIS) imagery was used to distinguish ship tracks embedded in closed, open, and undefined mesoscale cellular cloud structures. The impact of aerosol on the microphysical cloud properties in both the closed and open cell regimes were consistent with the changes predicted by the Twomey hypothesis. For the macrophysical changes, differences were observed between regimes. In the open cell regime, polluted clouds had significantly higher cloud tops (16%) and more liquid water (39%) than nearby unpolluted clouds. However, in the closed cell regime, polluted clouds exhibited no change in cloud top height and had less liquid water (-6%). Both microphysical (effective radius) and macrophysical (liquid water path) cloud properties contribute to a fractional change in cloud optical depth; in the closed cell regime the microphysical contribution was 3 times larger than the macrophysical contribution. However, the opposite was true in the open cell regime where the macrophysical contribution was nearly 2 times larger than the microphysical contribution because the aerosol probably increased cloud coverage. The results presented here demonstrate key differences aerosols have on the microphysical and macrophysical responses of boundary layer clouds between mesoscale stratocumulus convective regimes.

  5. Evidence for a regulatory role of diatom silicon transporters in cellular silicon responses.

    Science.gov (United States)

    Shrestha, Roshan P; Hildebrand, Mark

    2015-01-01

    The utilization of silicon by diatoms has both global and small-scale implications, from oceanic primary productivity to nanotechnological applications of their silica cell walls. The sensing and transport of silicic acid are key aspects of understanding diatom silicon utilization. At low silicic acid concentrations (silicon starvation. SIT1 and SIT2 were localized in the plasma membrane, and protein levels were generally inversely correlated with cellular silicon needs, with a distinct response being found when the two SITs were compared. We developed highly effective approaches for RNA interference and antisense knockdowns, the first such approaches developed for a centric diatom. SIT knockdown differentially affected the uptake of silicon and the incorporation of silicic acid and resulted in the induction of lipid accumulation under silicon starvation conditions far earlier than in the wild-type cells, suggesting that the cells were artificially sensing silicon limitation. The data suggest that the transport role of the SITs is relatively minor under conditions with sufficient silicic acid. Their primary role is to sense silicic acid levels to evaluate whether the cell can proceed with its cell wall formation and division processes.

  6. Nitric oxide modulates the temporal properties of the glutamate response in type 4 OFF bipolar cells.

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    Alex H Vielma

    Full Text Available Nitric oxide (NO is involved in retinal signal processing, but its cellular actions are only partly understood. An established source of retinal NO are NOACs, a group of nNOS-expressing amacrine cells which signal onto bipolar, other amacrine and ganglion cells in the inner plexiform layer. Here, we report that NO regulates glutamate responses in morphologically and electrophysiologically identified type 4 OFF cone bipolar cells through activation of the soluble guanylyl cyclase-cGMP-PKG pathway. The glutamate response of these cells consists of two components, a fast phasic current sensitive to kainate receptor agonists, and a secondary component with slow kinetics, inhibited by AMPA receptor antagonists. NO shortened the duration of the AMPA receptor-dependent component of the glutamate response, while the kainate receptor-dependent component remained unchanged. Application of 8-Br-cGMP mimicked this effect, while inhibition of soluble guanylate cyclase or protein kinase G prevented it, supporting a mechanism involving a cGMP signaling pathway. Notably, perfusion with a NOS-inhibitor prolonged the duration of the glutamate response, while the NO precursor L-arginine shortened it, in agreement with a modulation by endogenous NO. Furthermore, NO accelerated the response recovery during repeated stimulation of type 4 cone bipolar cells, suggesting that the temporal response properties of this OFF bipolar cell type are regulated by NO. These results reveal a novel cellular mechanism of NO signaling in the retina, and represent the first functional evidence of NO modulating OFF cone bipolar cells.

  7. BRITER: a BMP responsive osteoblast reporter cell line.

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    Prem Swaroop Yadav

    Full Text Available BACKGROUND: BMP signaling pathway is critical for vertebrate development and tissue homeostasis. High-throughput molecular genetic screening may reveal novel players regulating BMP signaling response while chemical genetic screening of BMP signaling modifiers may have clinical significance. It is therefore important to generate a cell-based tool to execute such screens. METHODOLOGY/PRINCIPAL FINDINGS: We have established a BMP responsive reporter cell line by stably integrating a BMP responsive dual luciferase reporter construct in the immortalized calvarial osteoblast cells isolated from tamoxifen inducible Bmp2; Bmp4 double conditional knockout mouse strain. This cell line, named BRITER (BMP Responsive Immortalized Reporter cell line, responds robustly, promptly and specifically to exogenously added BMP2 protein. The sensitivity to added BMP may be further increased by depleting the endogenous BMP2 and BMP4 proteins. CONCLUSION: As the dynamic range of the assay (for BMP responsiveness is very high for BRITER and as it responds specifically and promptly to exogenously added BMP2 protein, BRITER may be used effectively for chemical or molecular genetic screening for BMP signaling modifiers. Identification of novel molecular players capable of influencing BMP signaling pathway may have clinical significance.

  8. 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.

  9. 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.

  10. Proteome analysis of proliferative response of bystander cells adjacent to cells exposed to ionizing radiation.

    Science.gov (United States)

    Gerashchenko, Bogdan I; Yamagata, Akira; Oofusa, Ken; Yoshizato, Katsutoshi; de Toledo, Sonia M; Howell, Roger W

    2007-06-01

    Recently (Cytometry 2003, 56A, 71-80), we reported that direct cell-to-cell contact is required for stimulating proliferation of bystander rat liver cells (WB-F344) cocultured with irradiated cells, and neither functional gap junction intercellular communication nor long-range extracellular factors appear to be involved in this proliferative bystander response (PBR). The molecular basis for this response is unknown. Confluent monolayers of WB-F344 cells were exposed to 5-Gray (Gy) of gamma-rays. Irradiated cells were mixed with unirradiated cells and co-cultured for 24 h. Cells were harvested and protein expression was examined using 2-DE. Protein expression was also determined in cultures of unirradiated and 5-Gy irradiated cells. Proteins were identified by MS. Nucleophosmin (NPM)-1, a multifunctional nucleolar protein, was more highly expressed in bystander cells than in either unirradiated or 5-Gy irradiated cells. Enolase-alpha, a glycolytic enzyme, was present in acidic and basic variants in unirradiated cells. In bystander and 5-Gy irradiated cells, the basic variant was weakly expressed, whereas the acidic variant was overwhelmingly present. These data indicate that the presence of irradiated cells can affect NPM-1 and enolase-alpha in adjacent bystander cells. These proteins appear to participate in molecular events related to the PBR and suggest that this response may involve cellular defense, proliferation, and metabolism.

  11. 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

  12. PROLIFERATION RESPONSES IN PREIMMUNIZED MICE LYMPHOCYTES BY BORDETELLA PERTUSSIS CELL WALL COMPONENTS

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    Ashraf Mohabbati Mobarez

    2003-03-01

    Full Text Available Bordetella pertussis infects the respiratory tract of the human host and causes whooping cough in children. The nature of immunity against Bordetella pertussis infection and disease is poorly understood. The aim of this study was to investigate cell mediated immunity in mice immunized with outer membrane component of cell wall, of B. Pertussis.A group of mice were immunized with outer membrane complex (OMC and killed whole cell (WCV of B. pertussis, with an interval of 2 weeks. During a period of 7 weeks following the immunization, lymphocytes were isolated from lymph nodes of immunized mice. The in vitro proliferative response of isolated lymphocyte to stimulation with 20 ^g of 30 and 69 kDa outer membrane protein (OMP were measured as parameters for cell mediated immunity (CMI. The data were expressed as mean count per minute (CPMxlO3 after subtraction of the CPM of unstimulated control cultures. Lymphoblastogenic response was observed in immunized mice with WCV and OMC. At 30 days of post immunization a significant increase in response to 30 and 69 kDa OMP was observed, a small decrease in the response was evident against P30 and P69 at 60 and 120 days of post immunization, but the response was still higher than what was observed in control mice.Current findings indicate strongly the potential of outer membrane protein component of B. pertussis in proliferating lymphocytes in the mice.

  13. Social Responsibility and Professional Ethics in Management: Some Empirical Evidences at Country Levels

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    Cene Bavec

    2012-01-01

    Full Text Available In the presented exploratory study, we demonstrated some empiricalevidences on relations between social responsibility of business, managerialethics, and economic environment at county levels. We conducteddesk research on 41 countries using different secondary informationsources. We confirmed hypotheses, which associate higher socialresponsibility and ethics to openness and competitiveness of peopleand management, enhanced economic performance, higher economicfreedom, and lower level of corruption. The rationale behind the researchhypothesis is disputed question if socially responsible and ethicallymanaged business is economically more successful and sustainable.Evidently, in the most developed countries unsocial and unethicalbusiness behavior is not generally acceptable. However, in less developedeconomies profit is so high on the priority list that social responsibilityand ethics are academic questions.We hypothesize that companiesconsciously select where it is beneficial to be socially responsibleand ethical, and where it is more profitable to make business ruthlessly.We also tested the hypothesis that social responsibility contributes tothe resilience of economy. This hypothesis was partially confirmed andpartially rejected. Finally, we addressed a question if our results aremeaningful for individual organizations, as well.We could just say thatmore developed countries have a larger proportion of businesses thatbehave affirmatively regarding social and ethical issues, which meansthat they find it beneficial also at individual level.

  14. Responses to social exclusion in cultural context: evidence from farming and herding communities.

    Science.gov (United States)

    Uskul, Ayse K; Over, Harriet

    2014-05-01

    In a series of studies, we investigated the role of economic structures (farming vs. herding) and source of ostracism (close other vs. stranger) in social exclusion experiences. We first confirmed that herders rely on strangers to a greater extent than do farmers for economic success (validation study). Next, we verified that farmers and herders understand the concept of ostracism, and its emotional consequences, in similar ways (Study 1). The studies that followed provided converging evidence that cultural group membership shapes sensitivity and responses to social exclusion. Using different methodologies, in Studies 2 and 3, we showed that, whereas the psychological consequences of ostracism by close others are similar for farmers and herders, herders are more strongly affected by ostracism from strangers. The last two studies demonstrated that herders recommend more affiliative responses to ostracism by strangers than do farmers both to those involved in the ostracism event (Study 4) and to naïve individuals (Study 5). Moreover, Study 5 revealed that the amount of time spent with strangers mediated cultural group differences in the extent to which affiliative and aggressive actions are recommended following social exclusion by strangers. Taken together, these results demonstrate that the economic systems on which communities are based shape how their members interact with others and that this, in turn, can shape individuals' responses to social exclusion.

  15. Mismatch responses in the awake rat: evidence from epidural recordings of auditory cortical fields.

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    Fabienne Jung

    Full Text Available Detecting sudden environmental changes is crucial for the survival of humans and animals. In the human auditory system the mismatch negativity (MMN, a component of auditory evoked potentials (AEPs, reflects the violation of predictable stimulus regularities, established by the previous auditory sequence. Given the considerable potentiality of the MMN for clinical applications, establishing valid animal models that allow for detailed investigation of its neurophysiological mechanisms is important. Rodent studies, so far almost exclusively under anesthesia, have not provided decisive evidence whether an MMN analogue exists in rats. This may be due to several factors, including the effect of anesthesia. We therefore used epidural recordings in awake black hooded rats, from two auditory cortical areas in both hemispheres, and with bandpass filtered noise stimuli that were optimized in frequency and duration for eliciting MMN in rats. Using a classical oddball paradigm with frequency deviants, we detected mismatch responses at all four electrodes in primary and secondary auditory cortex, with morphological and functional properties similar to those known in humans, i.e., large amplitude biphasic differences that increased in amplitude with decreasing deviant probability. These mismatch responses significantly diminished in a control condition that removed the predictive context while controlling for presentation rate of the deviants. While our present study does not allow for disambiguating precisely the relative contribution of adaptation and prediction error processing to the observed mismatch responses, it demonstrates that MMN-like potentials can be obtained in awake and unrestrained rats.

  16. Evidence of Stereoscopic Surface Disambiguation in the Responses of V1 Neurons.

    Science.gov (United States)

    Samonds, Jason M; Tyler, Christopher W; Lee, Tai Sing

    2016-03-10

    For the important task of binocular depth perception from complex natural-image stimuli, the neurophysiological basis for disambiguating multiple matches between the eyes across similar features has remained a long-standing problem. Recurrent interactions among binocular disparity-tuned neurons in the primary visual cortex (V1) could play a role in stereoscopic computations by altering responses to favor the most likely depth interpretation for a given image pair. Psychophysical research has shown that binocular disparity stimuli displayed in 1 region of the visual field can be extrapolated into neighboring regions that contain ambiguous depth information. We tested whether neurons in macaque V1 interact in a similar manner and found that unambiguous binocular disparity stimuli displayed in the surrounding visual fields of disparity-selective V1 neurons indeed modified their responses when either bistable stereoscopic or uniform featureless stimuli were presented within their receptive field centers. The delayed timing of the response behavior compared with the timing of classical surround suppression and multiple control experiments suggests that these modulations are carried out by slower disparity-specific recurrent connections among V1 neurons. These results provide explicit evidence that the spatial interactions that are predicted by cooperative algorithms play an important role in solving the stereo correspondence problem.

  17. Mineralization and Osteoblast Cells Response of Nanograde Pearl Powders

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    Jian-Chih Chen

    2013-01-01

    Full Text Available The main objective of this study is to characterize the thermal, mineralization, and osteoblast cells response of pearl nanocrystallites. The results obtained from X-ray diffraction, FTIR spectra demonstrate that the pearl nano-crystallites can induce the formation of an HA layer on their surface in SBF, even after only short soaking periods. The in vitro cell response to nano-grade pearl powders is assessed by evaluating the cytotoxicity against a mouse embryonic fibroblast cell line and by characterizing the attachment ability and alkaline phosphatase activity of mouse bone cells (MC3T3-E1, abbreviated to E1 and bone marrow stromal precursor (D1 cells. The cytotoxicities of pearls were tested by the filtration and culture of NIH-3T3 mouse embryonic fibroblast cells. The viability of the cultured cells in media containing pearl crystallites for 24 and 72 h is greater than 90%. The bone cells seen in these micrographs are elongated and align predominately along the pearl specimen. The cells observed in these images also appeared well attached and cover the surface almost completely after 1 h. The pearl nanocrystallites had a positive effect on the osteogenic ability of ALP activity, and this promoted the osteogenic differentiation of MSCs significantly at explanations.

  18. Tertiary lymphoid organ development coincides with determinant spreading of the myelin-specific T cell response.

    Science.gov (United States)

    Kuerten, Stefanie; Schickel, Achim; Kerkloh, Christian; Recks, Mascha S; Addicks, Klaus; Ruddle, Nancy H; Lehmann, Paul V

    2012-12-01

    While the role of T cells has been studied extensively in multiple sclerosis (MS), the pathogenic contribution of B cells has only recently attracted major attention, when it was shown that B cell aggregates can develop in the meninges of a subset of MS patients and were suggested to be correlates of late-stage and more aggressive disease in this patient population. However, whether these aggregates actually exist has subsequently been questioned and their functional significance has remained unclear. Here, we studied myelin basic protein (MBP)-proteolipid protein (PLP)-induced experimental autoimmune encephalomyelitis (EAE), which is one of the few animal models for MS that is dependent on B cells. We provide evidence that B cell aggregation is reflective of lymphoid neogenesis in the central nervous system (CNS) in MBP-PLP-elicited EAE. B cell aggregation was present already few days after disease onset. With disease progression CNS B cell aggregates increasingly displayed the phenotype of tertiary lymphoid organs (TLOs). Our results further imply that these TLOs were not merely epiphenomena of the disease, but functionally active, supporting intrathecal determinant spreading of the myelin-specific T cell response. Our data suggest that the CNS is not a passive "immune-privileged" target organ, but rather a compartment, in which highly active immune responses can perpetuate and amplify the autoimmune pathology and thereby autonomously contribute to disease progression.

  19. 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.

  20. Biomedical Applications of the Cold Atmospheric Plasma: Cell Responses

    Science.gov (United States)

    Volotskova, Olga

    Current breakthrough research on cold atmospheric plasma (CAP) demonstrates that CAP has great potential in various areas, including medicine and biology, thus providing a new tool for living tissue treatment. Depending on the configuration the cold plasma sources can be used in the following areas: wound healing, skin diseases, hospital hygiene, sterilization, antifungal treatments, dental care, cosmetics targeted cell/tissue removal, and cancer treatments. This dissertation is focused on the studies of biomedical applications of cold atmospheric plasma jet based on helium flow and resultant cell responses to the cold plasma treatment. The studies were carried out on extra-cellular and intra-cellular levels in vitro. The main practical applications are wound healing and alternative to existing cancer therapy methods, areas of great interest and significant challenges. The CAP jet was built in the Micropropulsion and Nanotechnology Laboratory of Dr. Michael Keidar, as a part of multidisciplinary collaboration with the GW Medical School (Dr. M.A. Stepp) concerned with plasma medicine and bioengineering studies. Normal and cancer cells have two fundamental behavioral properties, proliferation and motility, which can be evaluated through cell migration rates and cell cycle progression. Various microscopic, spectroscopic and flow cytometry techniques were used to characterize cell responses to the cold plasma treatment. It was found that CAP effect on the cells is localized within the area of the treatment (of around ˜ 5mm in diameter). The migration rates of the normal skin cells can be reduced up to ˜ 40%. However, depending on the cell type the required treatment time is different, thus differential treatment of various cells presented in tissue is possible. The CAP effect on the migration was explained through the changes of the cell surface proteins/integrins. It was also found that normal and cancer cells respond differently to the CAP treatment under the same

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

    Directory of Open Access Journals (Sweden)

    Patcharaporn Tippayawat

    Full Text Available BACKGROUND: 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. METHODS: 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. FINDINGS: 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. CONCLUSIONS: 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.

  2. T-cell responses to dengue virus in humans.

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    Kurane, Ichiro; Matsutani, Takaji; Suzuki, Ryuji; Takasaki, Tomohiko; Kalayanarooj, Siripen; Green, Sharone; Rothman, Alan L; Ennis, Francis A

    2011-12-01

    Dengue virus (DENV) is a leading cause of morbidity and mortality in most tropical and subtropical areas of the world. Dengue virus infection induces specific CD4+CD8- and CD8+CD4- T cells in humans. In primary infection, T-cell responses to DENV are serotype cross-reactive, but the highest response is to the serotype that caused the infection. The epitopes recognized by DENV-specific T cells are located in most of the structural and non-structural proteins, but NS3 is the protein that is most dominantly recognized. In patients with dengue hemorrhagic fever (DHF) caused by secondary DENV infection, T cells are highly activated in vivo. These highly activated T cells are DENV-specific and oligoclonal. Multiple kinds of lymphokines are produced by the activated T cells, and it has been hypothesized that these lymphokines are responsible for induction of plasma leakage, one of the most characteristic features of DHF. Thus, T-cells play important roles in the pathogenesis of DHF and in the recovery from DENV infection.

  3. Metabolic monosaccharides altered cell responses to anticancer drugs.

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    Chen, Long; Liang, Jun F

    2012-06-01

    Metabolic glycoengineering has been used to manipulate the glycochemistry of cell surfaces and thus the cell/cell interaction, cell adhesion, and cell migration. However, potential application of glycoengineering in pharmaceutical sciences has not been studied until recently. Here, we reported that Ac(4)ManNAc, an analog of N-acetyl-D-mannosamine (ManNAc), could affect cell responses to anticancer drugs. Although cells from different tissues and organs responded to Ac(4)ManNAc treatment differently, treated cells with increased sialic acid contents showed dramatically reduced sensitivity (up to 130 times) to anti-cancer drugs as tested on various drugs with distinct chemical structures and acting mechanisms. Neither increased P-glycoprotein activity nor decreased drug uptake was observed during the course of Ac(4)ManNAc treatment. However, greatly altered intracellular drug distributions were observed. Most intracellular daunorubicin was found in the perinuclear region, but not the expected nuclei in the Ac(4)ManNAc treated cells. Since sialoglycoproteins and gangliosides were synthesized in the Golgi, intracellular glycans affected intracellular signal transduction and drug distributions seem to be the main reason for Ac(4)ManNAc affected cell sensitivity to anticancer drugs. It was interesting to find that although Ac(4)ManNAc treated breast cancer cells (MDA-MB-231) maintained the same sensitivity to 5-Fluorouracil, the IC(50) value of 5-Fluorouracil to the same Ac(4)ManNAc treated normal cells (MCF-10A) was increased by more than 20 times. Thus, this Ac(4)ManNAc treatment enlarged drug response difference between normal and tumor cells provides a unique opportunity to further improve the selectivity and therapeutic efficiency of anticancer drugs.

  4. The BALB/c mouse B-cell response to pigeon cytochrome c initiates as a heteroclitic response specific for the self antigen mouse cytochrome c.

    Science.gov (United States)

    Minnerath, J M; Wakem, L P; Comfort, L L; Sherman, F; Jemmerson, R

    1995-01-01

    Direct evidence is presented in support of the longstanding but unproven hypothesis that B lymphocytes specific for self antigens (Ags) can be used in the immune response to foreign Ags. We show that the B cells in BALB/c mic responding early to pigeon cytochrome c (CYT) produce antibodies that recognize and bind the major antigenic site on mouse CYT with greater affinity than they bind pigeon CYT i.e., they are heteroclitic for the self Ag. Furthermore, these B cells express the same combination of immunoglobulin variable region (V) genes that are known to be used in B-cell recognition of mouse CYT. Over time, the response to pigeon CYT becomes more specific for the foreign Ag through the recruitment of B cells expressing different combinations of V genes and, possibly, somatic mutation of the mouse CYT specific B cells from early in the response. Cross-recognition of pigeon CYT by mouse CYT-specific B cells results from the sharing of critical amino acid residues by the two Ags. Although B-cell recognition of the self Ag, mouse CYT, is very specific, which limits the extent to which foreign Ags can cross-activate the autoreactive B cells, it is possible that polyreactive B cells to other self Ags may be used more frequently in response to foreign Ags. PMID:8618905

  5. Orientational Polarizability and Stress Response of Biological Cells

    Science.gov (United States)

    Safran, S. A.; de, R.; Zemel, A.

    We present a theoretical treatment of the orientational response to external stress of active, contractile cells embedded in a gel-like elastic medium. The theory includes random forces as well as forces that arise from the deformation of the matrix and those due to the internal regulation of the stress fibers and focal adhesions of the cell. We calculate both the static and high frequency limits of the orientational response in terms of the cellular polarizability. For systems in which the forces due to regulation and activity dominate the mechanical forces, we show that there is a non-linear dynamical response which, in the high frequency limit, causes the cell to orient nearly perpendicular to the direction of the applied stress.

  6. Studies on responsiveness of hepatoma cells to catecholamines. VI. Characteristics of adrenoceptors and adenylate cyclase response in rat ascites hepatoma cells and human hepatoma cells.

    Science.gov (United States)

    Sanae, F; Kohei, K; Nomura, M; Miyamoto, K

    1992-06-01

    Alpha 1, alpha 2- and beta-Adrenoceptor densities and catecholamine responsiveness in established hepatoma cells, rat ascites hepatoma AH13, AH66, AH66F, AH109A, AH130 and AH7974 cells and human hepatocellular carcinoma HLF and HepG2 cells, were compared with those in normal rat hepatocytes and Chang liver cells. Alpha 1-Adrenoceptor densities measured by [3H]prazosin bindings were not detected in all hepatoma cell lines. Alpha 2-Adrenoceptor densities measured by [3H]clonidine bindings were also barely detected in hepatoma cell lines except for AH130 cells and HepG2 cells. Regarding beta-adrenoceptor, AH109A, AH130 and AH7974 cells had much more [125I]iodocyanopindolol binding sites than normal rat hepatocytes, although we could not detect the binding in HepG2 cells. Adenylate cyclase of normal rat hepatocyte and Chang liver cells were stimulated by beta 2-adrenergic agonist salbutamol, while the cyclase in hepatoma cells had no beta 2-adrenergic response but a beta 1-type response. These findings indicate that the characteristics of adrenergic response in hepatoma cell lines is very different from that in normal hepatocytes, suggesting a participation in the hepatocarcinogenesis and/or the autonomous proliferation of hepatoma cells.

  7. B cells regulate CD4+ T cell responses to papain following B cell receptor-independent papain uptake.

    Science.gov (United States)

    Dwyer, Daniel F; Woodruff, Matthew C; Carroll, Michael C; Austen, K Frank; Gurish, Michael F

    2014-07-15

    Papain, a cysteine protease allergen with inherent adjuvant activity, induces potent IL-4 expression by T cells in the popliteal lymph nodes of mice following footpad immunization. In this study, we identify a novel, non-BCR-mediated capacity for B cells to rapidly bind and internalize papain. B cells subsequently regulate the adaptive immune response by enhancing ICOS expression on CD4(+) T cells and amplifying Th2 and follicular helper T cell induction. Ab blockade of ICOS ligand, expressed by popliteal lymph node B cells, but not dendritic cells, at the peak of the response inhibits IL-4 responses in wild-type mice but not B cell-deficient mice. Thus, B cells play a critical role in amplifying adjuvant-dependent Th2 polarization following noncanonical acquisition and internalization of the cysteine protease papain.

  8. 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.

  9. The dendritic cell response to classic, emerging, and homeostatic danger signals. Implications for autoimmunity.

    Science.gov (United States)

    Gallo, Paul M; Gallucci, Stefania

    2013-01-01

    Dendritic cells (DCs) initiate and control immune responses, participate in the maintenance of immunological tolerance and are pivotal players in the pathogenesis of autoimmunity. In patients with autoimmune disease and in experimental animal models of autoimmunity, DCs show abnormalities in both numbers and activation state, expressing immunogenic levels of costimulatory molecules and pro-inflammatory cytokines. Exogenous and endogenous danger signals activate DCs to stimulate the immune response. Classic endogenous danger signals are released, activated, or secreted by host cells and tissues experiencing stress, damage, and non-physiologic cell death; and are therefore referred to as damage-associated molecular patterns (DAMPs). Some DAMPs are released from cells, where they are normally sequestered, during necrosis (e.g., heat shock proteins, uric acid, ATP, HMGB1, mitochondria-derived molecules). Others are actively secreted, like Type I Interferons. Here we discuss important DAMPs in the context of autoimmunity. For some, there is a clear pathogenic link (e.g., nucleic acids and lupus). For others, there is less evidence. Additionally, we explore emerging danger signals. These include inorganic materials and man-made technologies (e.g., nanomaterials) developed as novel therapeutic approaches. Some nanomaterials can activate DCs and may trigger unintended inflammatory responses. Finally, we will review "homeostatic danger signals," danger signals that do not derive directly from pathogens or dying cells but are associated with perturbations of tissue/cell homeostasis and may signal pathological stress. These signals, like acidosis, hypoxia, and changes in osmolarity, also play a role in inflammation and autoimmunity.

  10. 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.

  11. Th17 effector cells support B cell responses outside of germinal centres.

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    Agapitos Patakas

    Full Text Available Th17 cells are pro-inflammatory CD4⁺T cells, which are important in immune responses against fungal pathogens and extracellular bacteria and have also been implicated in various autoimmune syndromes. However, their role in supporting B cell responses in these scenarios remains unclear, representing a significant lapse in our understanding of the role Th17 play in vaccine responses and the regulation of autoimmunity. We employed T cell and B cell receptor transgenic mice specific for model antigens, and adoptive transfer approaches that allowed the tracking of cognate B and T cells in situ and ex vivo using immunological methods. We have found that T cells activated under Th17 polarising conditions have a greater capacity to provide cognate B cell help compared with Th1 polarised populations, supporting higher expansion of antigen specific B cells and enhanced antibody titres. This advantage is associated with the increased persistence of Th17 polarised cells in areas of the lymph nodes where they can provide help (i.e. the B cell follicles. Also the Th17 cells are characterised by their higher expression of ICOS, a costimulatory molecule important for B cell help. Surprisingly, contrary to published reports, Th17 cells were not detected inside germinal centres, although they were found in close proximity to cognate B cells in the follicle early in the genesis of the humoral immune response. These data indicate that, Th17 cells have a more significant role earlier in the initiation/development of the germinal centre response and/or germinal centre-independent events, consistent with their early effector status.

  12. Macrophages in cardiac homeostasis, injury responses and progenitor cell mobilisation

    Directory of Open Access Journals (Sweden)

    Alexander R. Pinto

    2014-11-01

    Full Text Available Macrophages are an immune cell type found in every organ of the body. Classically, macrophages are recognised as housekeeping cells involved in the detection of foreign antigens and danger signatures, and the clearance of tissue debris. However, macrophages are increasingly recognised as a highly versatile cell type with a diverse range of functions that are important for tissue homeostasis and injury responses. Recent research findings suggest that macrophages contribute to tissue regeneration and may play a role in the activation and mobilisation of stem cells. This review describes recent advances in our understanding of the role played by macrophages in cardiac tissue maintenance and repair following injury. We examine the involvement of exogenous and resident tissue macrophages in cardiac inflammatory responses and their potential activity in regulating cardiac regeneration.

  13. An epistemological shift: from evidence-based medicine to epistemological responsibility.

    Science.gov (United States)

    van Baalen, Sophie; Boon, Mieke

    2015-06-01

    In decision making concerning the diagnosis and treatment of patients, doctors have a responsibility to do this to the best of their abilities. Yet we argue that the current paradigm for best medical practice - evidence-based medicine (EBM) - does not always support this responsibility. EBM was developed to promote a more scientific approach to the practice of medicine. This includes the use of randomized controlled trials in the testing of new treatments and prophylactics and rule-based reasoning in clinical decision making. But critics of EBM claim that such a scientific approach does not always work in the clinic. In this article, we build on this critique and argue that rule-based reasoning and the use of general guidelines as promoted by EBM does not accommodate the complex reasoning of doctors in clinical decision making. Instead, we propose that a new medical epistemology is needed that accounts for complex reasoning styles in medical practice and at the same time maintains the quality usually associated with 'scientific'. The medical epistemology we propose conforms to the epistemological responsibility of doctors, which involves a specific professional attitude and epistemological skills. Instead of deferring part of the professional responsibility to strict clinical guidelines, as EBM allows for, our alternative epistemology holds doctors accountable for epistemic considerations in clinical decision making towards the diagnosis and treatment plan of individual patients. One of the key intellectual challenges of doctors is the ability to bring together heterogeneous pieces of information to construct a coherent 'picture' of a specific patient. In the proposed epistemology, we consider this 'picture' as an epistemological tool that may then be employed in the diagnosis and treatment of a specific patient.

  14. Evidence from retractor bulbi EMG for linearized motor control of conditioned nictitating membrane responses.

    Science.gov (United States)

    Lepora, N F; Mavritsaki, E; Porrill, J; Yeo, C H; Evinger, C; Dean, P

    2007-10-01

    Classical conditioning of nictitating membrane (NM) responses in rabbits is a robust model learning system, and experimental evidence indicates that conditioned responses (CRs) are controlled by the cerebellum. It is unknown whether cerebellar control signals deal directly with the complex nonlinearities of the plant (blink-related muscles and peripheral tissues) or whether the plant is linearized to ensure a simple relation between cerebellar neuronal firing and CR profile. To study this question, the retractor bulbi muscle EMG was recorded with implanted electrodes during NM conditioning. Pooled activity in accessory abducens motoneurons was estimated from spike trains extracted from the EMG traces, and its temporal profile was found to have an approximately Gaussian shape with peak amplitude linearly related to CR amplitude. The relation between motoneuron activity and CR profiles was accurately fitted by a first-order linear filter, with each spike input producing an exponentially decaying impulse response with time constant of order 0.1 s. Application of this first-order plant model to CR data from other laboratories suggested that, in these cases also, motoneuron activity had a Gaussian profile, with time-of-peak close to unconditioned stimulus (US) onset and SD proportional to the interval between conditioned stimulus and US onsets. These results suggest that for conditioned NM responses the cerebellum is presented with a simplified "virtual" plant that is a linearized version of the underlying nonlinear biological system. Analysis of a detailed plant model suggests that one method for linearising the plant would be appropriate recruitment of motor units.

  15. Ultraviolet responses of a heterojunction Si quantum dot solar cell.

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    Lee, Seong Hyun; Kwak, Gyea Young; Hong, Songwoung; Kim, Chanhong; Kim, Sung; Kim, Ansoon; Kim, Kyung Joong

    2017-01-20

    We investigated the ultraviolet (UV) responses of a heterojunction Si quantum dot (QD) solar cell consisting of p-type Si-QDs fabricated on a n-type crystalline Si (p-Si-QD/n-c-Si HJSC). The UV responses were compared with a conventional n-type crystalline Si solar cell (n-c-Si SC). The external and internal quantum efficiency results of the p-Si-QD/n-c-Si HJSC exhibited a clear enhancement in the UV responses (300-400 nm), which was not observed in the n-c-Si SC. Based on the results of the cell reflectance and bias-dependent responses, we expect that almost all UV responses occur in the p-Si-QD layer, and the generated carriers can be transported via the Si-QD layer due to the formation of a sufficient electric filed. As a result, a high power conversion efficiency of 14.5% was achieved from the p-Si-QD/n-c-Si HJSC. By reducing the thickness of the n-Si substrate from 650 μm to 300 μm, more enhanced power conversion efficiency of 14.8% was obtained which is the highest value among the reported Si-QD based solar cells to date.

  16. Ultraviolet responses of a heterojunction Si quantum dot solar cell

    Science.gov (United States)

    Lee, Seong Hyun; Kwak, Gyea Young; Hong, Songwoung; Kim, Chanhong; Kim, Sung; Kim, Ansoon; Kim, Kyung Joong

    2017-01-01

    We investigated the ultraviolet (UV) responses of a heterojunction Si quantum dot (QD) solar cell consisting of p-type Si-QDs fabricated on a n-type crystalline Si (p-Si-QD/n-c-Si HJSC). The UV responses were compared with a conventional n-type crystalline Si solar cell (n-c-Si SC). The external and internal quantum efficiency results of the p-Si-QD/n-c-Si HJSC exhibited a clear enhancement in the UV responses (300–400 nm), which was not observed in the n-c-Si SC. Based on the results of the cell reflectance and bias-dependent responses, we expect that almost all UV responses occur in the p-Si-QD layer, and the generated carriers can be transported via the Si-QD layer due to the formation of a sufficient electric filed. As a result, a high power conversion efficiency of 14.5% was achieved from the p-Si-QD/n-c-Si HJSC. By reducing the thickness of the n-Si substrate from 650 μm to 300 μm, more enhanced power conversion efficiency of 14.8% was obtained which is the highest value among the reported Si-QD based solar cells to date.

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

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    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.

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

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    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.

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

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    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.

  20. Sensory Transduction of the CO2 Response of Guard Cells

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Eduardo Zeiger

    2003-06-30

    Stomata have a key role in the regulation of gas exchange and intercellular CO2 concentrations of leaves. Guard cells sense internal and external signals in the leaf environment and transduce these signals into osmoregulatory processes that control stomatal apertures. This research proposal addresses the characterization of the sensory transduction of the CO2 signal in guard cells. Recent studies have shown that in Vicia leaves kept at constant light and temperature in a growth chamber, changes in ambient CO2 concentrations cause large changes in guard cell zeaxanthin that are linear with CO2-dependent changes in stomatal apertures. Research proposed here will test the hypothesis that zeaxanthin function as a transducer of CO2 signals in guard cells. Three central aspects of this hypothesis will be investigated: CO2 sensing by the carboxylation reaction of Rubisco in the guard cell chloroplast, which would modulate zeaxanthin concentrations via changes in lumen pH; transduction of the CO2 signal by zeaxanthin via a transducing cascade that controls guard cell osmoregulation; and blue light dependence of the CO2 signal transduction by zeaxanthin, required for the formation of an isomeric form of zeaxanthin that is physiologically active as a transducer. The role of Rubisco in CO2 sensing will be investigated in experiments characterizing the stomatal response to CO2 in the Arabidopsis mutants R100 and rca-, which have reduced rates of Rubisco-dependent carboxylation. The role of zeaxanthin as a CO2 transducer will be studied in npq1, a zeaxanthin-less mutant. The blue light-dependence of CO2 sensing will be studied in experiments characterizing the stomatal response to CO2 under red light. Arabidopsis mutants will also be used in further studies of an acclimation of the stomatal response to CO2, and a possible role of the xanthophyll cycle of the guard cell chloroplast in acclimations of the stomatal response to CO2. Studies on the osmoregulatory role of sucrose in

  1. Fetal cell carcinogenesis of the thyroid: a modified theory based on recent evidence.

    Science.gov (United States)

    Takano, Toru

    2014-01-01

    Thyroid cancer cells were believed to be generated by multi-step carcinogenesis, in which cancer cells are derived from thyrocytes, via multiple incidences of damage to their genome, especially in oncogenes or anti-oncogenes that accelerate proliferation or foster malignant phenotypes, such as the ability to invade the surrounding tissue or metastasize to distant organs, until a new hypothesis, fetal cell carcinogenesis, was presented. In fetal cell carcinogenesis, thyroid tumor cells are assumed to be derived from three types of fetal thyroid cell which only exist in fetuses or young children, namely, thyroid stem cells (TSCs), thyroblasts and prothyrocytes, by proliferation without differentiation. Genomic alternations, such as RET/PTC and PAX8-PPARγ1 rearrangements and a mutation in the BRAF gene, play an oncogenic role by preventing thyroid fetal cells from differentiating. Fetal cell carcinogenesis effectively explains recent molecular and clinical evidence regarding thyroid cancer, including thyroid cancer initiating cells (TCICs), and it underscores the importance of identifying a stem cells and clarifying the molecular mechanism of organ development in cancer research. It introduces three important concepts, the reverse approach, stem cell crisis and mature and immature cancers. Further, it implies that analysis of a small population of cells in a cancer tissue will be a key technique in establishing future laboratory tests. In the contrary, mass analysis such as gene expression profiling, whole genomic scan, and proteomics analysis may have definite limitations since they can only provide information based on many cells.

  2. Mechanistic insights into aging, cell cycle progression, and stress response

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    Troy Anthony Alan Harkness

    2012-06-01

    Full Text Available The longevity of an organism depends on the health of its cells. Throughout life cells are exposed to numerous intrinsic and extrinsic stresses, such as free radicals, generated through mitochondrial electron transport, and ultraviolet irradiation. The cell has evolved numerous mechanisms to scavenge free radicals and repair damage induced by these insults. One mechanism employed by the yeast Saccharomyces cerevisiae to combat stress utilizes the Anaphase Promoting Complex (APC, an essential multi-subunit ubiquitin-protein ligase structurally and functionally conserved from yeast to humans that controls progression through mitosis and G1. We have observed that yeast cells expressing compromised APC subunits are sensitive to multiple stresses and have shorter replicative and chronological lifespans. In a pathway that runs parallel to that regulated by the APC, members of the Forkhead box (Fox transcription factor family also regulate stress responses. The yeast Fox orthologues Fkh1 and Fkh2 appear to drive the transcription of stress response factors and slow early G1 progression, while the APC seems to regulate chromatin structure, chromosome segregation, and resetting of the transcriptome in early G1. In contrast, under non-stress conditions, the Fkhs play a complex role in cell cycle progression, partially through activation of the APC. Direct and indirect interactions between the APC and the yeast Fkhs appear to be pivotal for lifespan determination. Here we explore the potential for these interactions to be evolutionarily conserved as a mechanism to balance cell cycle regulation with stress responses.

  3. Cell response of anodized nanotubes on titanium and titanium alloys.

    Science.gov (United States)

    Minagar, Sepideh; Wang, James; Berndt, Christopher C; Ivanova, Elena P; Wen, Cuie

    2013-09-01

    Titanium and titanium alloy implants that have been demonstrated to be more biocompatible than other metallic implant materials, such as Co-Cr alloys and stainless steels, must also be accepted by bone cells, bonding with and growing on them to prevent loosening. Highly ordered nanoporous arrays of titanium dioxide that form on titanium surface by anodic oxidation are receiving increasing research interest due to their effectiveness in promoting osseointegration. The response of bone cells to implant materials depends on the topography, physicochemistry, mechanics, and electronics of the implant surface and this influences cell behavior, such as adhesion, proliferation, shape, migration, survival, and differentiation; for example the existing anions on the surface of a titanium implant make it negative and this affects the interaction with negative fibronectin (FN). Although optimal nanosize of reproducible titania nanotubes has not been reported due to different protocols used in studies, cell response was more sensitive to titania nanotubes with nanometer diameter and interspace. By annealing, amorphous TiO2 nanotubes change to a crystalline form and become more hydrophilic, resulting in an encouraging effect on cell behavior. The crystalline size and thickness of the bone-like apatite that forms on the titania nanotubes after implantation are also affected by the diameter and shape. This review describes how changes in nanotube morphologies, such as the tube diameter, the thickness of the nanotube layer, and the crystalline structure, influence the response of cells.

  4. Cell Wall Metabolism in Response to Abiotic Stress

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    Hyacinthe Le Gall

    2015-02-01

    Full Text Available 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.

  5. CTLA-4 blockade enhances polyfunctional NY-ESO-1 specific T cell responses in metastatic melanoma patients with clinical benefit.

    Science.gov (United States)

    Yuan, Jianda; Gnjatic, Sacha; Li, Hao; Powel, Sarah; Gallardo, Humilidad F; Ritter, Erika; Ku, Geoffrey Y; Jungbluth, Achim A; Segal, Neil H; Rasalan, Teresa S; Manukian, Gregor; Xu, Yinyan; Roman, Ruth-Ann; Terzulli, Stephanie L; Heywood, Melanie; Pogoriler, Evelina; Ritter, Gerd; Old, Lloyd J; Allison, James P; Wolchok, Jedd D

    2008-12-23

    Blockade of inhibitory signals mediated by cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) has been shown to enhance T cell responses and induce durable clinical responses in patients with metastatic melanoma. The functional impact of anti-CTLA-4 therapy on human immune responses is still unclear. To explore this, we analyzed immune-related adverse events and immune responses in metastatic melanoma patients treated with ipilimumab, a fully human anti-CTLA-4 monoclonal antibody. Fifteen patients were selected on the basis of availability of suitable specimens for immunologic monitoring, and eight of these showed evidence of clinical benefit. Five of the eight patients with evidence of clinical benefit had NY-ESO-1 antibody, whereas none of seven clinical non-responders was seropositive for NY-ESO-1. All five NY-ESO-1 seropositive patients had clearly detectable CD4(+) and CD8(+) T cells against NY-ESO-1 following treatment with ipilimumab. One NY-ESO-1 seronegative clinical responder also had a NY-ESO-1 CD4(+) and CD8(+) T cell response, possibly related to prior vaccination with NY-ESO-1. Among five clinical non-responders analyzed, only one had a NY-ESO-1 CD4(+) T cell response and this patient did not have detectable anti-NY-ESO-1 antibody. Overall, NY-ESO-1-specific T cell responses increased in frequency and functionality during anti-CTLA-4 treatment, revealing a polyfunctional response pattern of IFN-gamma, MIP-1beta and TNF-alpha. We therefore suggest that CTLA-4 blockade enhanced NY-ESO-1 antigen-specific B cell and T cell immune responses in patients with durable objective clinical responses and stable disease. These data provide an immunologic rationale for the efficacy of anti-CTLA-4 therapy and call for immunotherapeutic designs that combine NY-ESO-1 vaccination with CTLA-4 blockade.

  6. Clustering in Cell Cycle Dynamics with General Response/Signaling Feedback

    CERN Document Server

    Young, Todd; Buckalew, Richard; Moses, Gregory; Boczko, Erik; 10.1016/j.jtbi.2011.10.002.

    2011-01-01

    Motivated by experimental and theoretical work on autonomous oscillations in yeast, we analyze ordinary differential equations models of large populations of cells with cell-cycle dependent feedback. We assume a particular type of feedback that we call Responsive/Signaling (RS), but do not specify a functional form of the feedback. We study the dynamics and emergent behaviour of solutions, particularly temporal clustering and stability of clustered solutions. We establish the existence of certain periodic clustered solutions as well as "uniform" solutions and add to the evidence that cell-cycle dependent feedback robustly leads to cell-cycle clustering. We highlight the fundamental differences in dynamics between systems with negative and positive feedback. For positive feedback systems the most important mechanism seems to be the stability of individual isolated clusters. On the other hand we find that in negative feedback systems, clusters must interact with each other to reinforce coherence. We conclude fr...

  7. Innate lymphoid cells regulate CD4+ T-cell responses to intestinal commensal bacteria.

    Science.gov (United States)

    Hepworth, Matthew R; Monticelli, Laurel A; Fung, Thomas C; Ziegler, Carly G K; Grunberg, Stephanie; Sinha, Rohini; Mantegazza, Adriana R; Ma, Hak-Ling; Crawford, Alison; Angelosanto, Jill M; Wherry, E John; Koni, Pandelakis A; Bushman, Frederic D; Elson, Charles O; Eberl, Gérard; Artis, David; Sonnenberg, Gregory F

    2013-06-06

    Innate lymphoid cells (ILCs) are a recently characterized family of immune cells that have critical roles in cytokine-mediated regulation of intestinal epithelial cell barrier integrity. Alterations in ILC responses are associated with multiple chronic human diseases, including inflammatory bowel disease, implicating a role for ILCs in disease pathogenesis. Owing to an inability to target ILCs selectively, experimental studies assessing ILC function have predominantly used mice lacking adaptive immune cells. However, in lymphocyte-sufficient hosts ILCs are vastly outnumbered by CD4(+) T cells, which express similar profiles of effector cytokines. Therefore, the function of ILCs in the presence of adaptive immunity and their potential to influence adaptive immune cell responses remain unknown. To test this, we used genetic or antibody-mediated depletion strategies to target murine ILCs in the presence of an adaptive immune system. We show that loss of retinoic-acid-receptor-related orphan receptor-γt-positive (RORγt(+)) ILCs was associated with dysregulated adaptive immune cell responses against commensal bacteria and low-grade systemic inflammation. Remarkably, ILC-mediated regulation of adaptive immune cells occurred independently of interleukin (IL)-17A, IL-22 or IL-23. Genome-wide transcriptional profiling and functional analyses revealed that RORγt(+) ILCs express major histocompatibility complex class II (MHCII) and can process and present antigen. However, rather than inducing T-cell proliferation, ILCs acted to limit commensal bacteria-specific CD4(+) T-cell responses. Consistent with this, selective deletion of MHCII in murine RORγt(+) ILCs resulted in dysregulated commensal bacteria-dependent CD4(+) T-cell responses that promoted spontaneous intestinal inflammation. These data identify that ILCs maintain intestinal homeostasis through MHCII-dependent interactions with CD4(+) T cells that limit pathological adaptive immune cell responses to commensal

  8. 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.

  9. Biomechanical changes in endothelial cells result from an inflammatory response

    Science.gov (United States)

    Vaitkus, Janina; Stroka, Kimberly; Aranda-Espinoza, Helim

    2012-02-01

    During periods of infection and disease, the immune system induces the release of TNF-α, an inflammatory cytokine, from a variety of cell types, such as macrophages. TNF-α, while circulating in the vasculature, binds to the apical surface of endothelial cells and causes a wide range of biological and mechanical changes to the endothelium. While the biological changes have been widely studied, the biomechanical aspects have been largely unexplored. Here, we investigated the biomechanical changes of the endothelium as a function of TNF-α treatment. First, we studied the traction forces applied by the endothelium, an effect that is much less studied than others. Through the use of traction force microscopy, we found that TNF-α causes an increase in traction forces applied by the endothelial cells as compared to non-treated cells. Then, we investigated cell morphology, cell mechanics, migration, and cytoskeletal dynamics. We found that in addition to increasing applied traction forces, TNF-α causes an increase in cell area and aspect ratio on average, as well as a shift in the organization of F-actin filaments within the cell. Combining these findings together, our results show that an inflammatory response heavily impacts the morphology, cell mechanics, migration, cytoskeletal dynamics, and applied traction forces of endothelial cells.

  10. Endocycling cells do not apoptose in response to DNA rereplication genotoxic stress.

    Science.gov (United States)

    Mehrotra, Sonam; Maqbool, Shahina B; Kolpakas, Alexis; Murnen, Katherine; Calvi, Brian R

    2008-11-15

    Initiation of DNA replication at origins more than once per cell cycle results in rereplication and has been implicated in cancer. Here we use Drosophila to examine the checkpoint responses to rereplication in a developmental context. We find that increased Double-parked (Dup), the Drosophila ortholog of Cdt1, results in rereplication and DNA damage. In most cells, this rereplication triggers caspase activation and apoptotic cell death mediated by both p53-dependent and -independent pathways. Elevated Dup also caused DNA damage in endocycling cells, which switch to a G/S cycle during normal development, indicating that rereplication and the endocycling DNA reduplication program are distinct processes. Unexpectedly, however, endocycling cells do not apoptose regardless of tissue type. Our combined evidence suggests that endocycling apoptosis is repressed in part because proapoptotic gene promoters are silenced. Normal endocycling cells had DNA lesions near heterochromatin, which increased after rereplication, explaining why endocycling cells must constantly repress the genotoxic apoptotic response. Our results reveal a novel regulation of apoptosis in development and new insights into the little-understood endocycle. Similar mechanisms may operate during vertebrate development, with implications for cancer predisposition in certain tissues.

  11. Mouse Testicular Cell Type-Specific Antiviral Response against Mumps Virus Replication

    Science.gov (United States)

    Wu, Han; Zhao, Xiang; Wang, Fei; Jiang, Qian; Shi, Lili; Gong, Maolei; Liu, Weihua; Gao, Bo; Song, Chengyi; Li, Qihan; Chen, Yongmei; Han, Daishu

    2017-01-01

    Mumps virus (MuV) infection has high tropism to the testis and usually leads to orchitis, an etiological factor in male infertility. However, MuV replication in testicular cells and the cellular antiviral responses against MuV are not fully understood. The present study showed that MuV infected the majority of testicular cells, including Leydig cells (LC), testicular macrophages, Sertoli cells (SC), and male germ cells (GC). MuV was replicated at relatively high efficiencies in SC compared with LC and testicular macrophages. In contrast, MuV did not replicate in male GC. Notably, testicular cells exhibited different innate antiviral responses against MuV replication. We showed that interferon β (IFN-β) inhibited MuV replication in LC, macrophages, and SC, which were associated with the upregulation of major antiviral proteins. We provided primary evidence that autophagy plays a role in blocking MuV replication in male GC. Autophagy was also involved in limiting MuV replication in testicular macrophages but not in Leydig and SC. These findings indicate the involvement of the innate defense against MuV replication in testicular cells. PMID:28239382

  12. 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.

  13. Corporate Social Responsibility Disclosure: Evidence from Shariah-Compliant Companies in ACE Market of Bursa Malaysia

    Directory of Open Access Journals (Sweden)

    Mohd Rashdan Sallehuddin

    2013-11-01

    Full Text Available This study seeks to investigate the degree of corporate social responsibility disclosure in company’s annual report. The scope is further narrowed to the Shariah-compliant companies in ACE Market of Bursa Malaysia. A total of 102 company annual reports for the year 2012 are examined to analyze the companies’ reporting practice using content analysis. Regression analysis was used to examine the relationship between corporate social responsibility disclosure (CSRD and independent variables consisting of independent non-executive directors, Muslim chairman/president of the board, CEO duality, frequency of board meetings and auditor types. Study findings suggest that there is fair amount of CSR disclosure amongst Shariah-compliant companies listed with Bursa Malaysia. The results of the study demonstrate only the type of auditors employed have a significant relationship with CSR disclosure. In contrast, the extent of CSR disclosure is insignificant with regard to the proportion of independent non-executive directors, Muslim chairman/president of the board, CEO duality and frequency of board meetings. The research shows that the level of CSR disclosures among Shariah-compliant companies in ACE Market is moderate but the varieties of disclosure are impressive. This study provides evidence for regulatory bodies such as Shariah Advisory Council (SAC of the Securities Commission Malaysia and Bursa Malaysia to look further at Shariah-compliance guidelines and to enforce new policies on corporate social disclosure

  14. 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.

  15. Responses of cells in plasma-activated medium

    Science.gov (United States)

    Tanaka, Hiromasa; Mizuno, Masaaki; Ishikawa, Kenji; Takeda, Keigo; Hashizume, Hiroshi; Nakamura, Kae; Kajiyama, Hiroaki; Kano, Hiroyuki; Okazaki, Yasumasa; Toyokuni, Shinya; Maruyama, Shoichi; Kodera, Yasuhiro; Terasaki, Hiroko; Adachi, Tetsuo; Kato, Masashi; Kikkawa, Fumitaka; Hori, Masaru

    2015-09-01

    Plasma consists of electrons, ions, radicals, and lights, and produces various reactive species in gas and liquid phase. Cells receive various inputs from their circumstances, and induce several physiological outputs. Our goal is to clarify the relationships between plasma inputs and physiological outputs. Plasma-activated medium (PAM) is a circumstance that plasma provides cells and our previous studies suggest that PAM is a promising tool for cancer therapy. However, the mode of actions remains to be elucidated. We propose survival and proliferation signaling networks as well as redox signaling networks are key factors to understand cellular responses of PAM-treated glioblastoma cells.

  16. Type I interferon suppresses virus-specific B cell responses by modulating CD8+ T cell differentiation

    Science.gov (United States)

    Moseman, E. Ashley; Wu, Tuoqi; de la Torre, Juan Carlos; Schwartzberg, Pamela L.; McGavern, Dorian B.

    2016-01-01

    Studies have established a role for T cells in resolving persistent viral infections, yet emerging evidence indicates that both T and B cells are required to control some viruses. During persistent infection, a marked lag or failure to generate neutralizing antibodies is commonly observed and likely contributes to an inability to control certain pathogens. Using lymphocytic choriomeningitis virus (LCMV) as a model, we have examined how a persistent viral infection can suppress neutralizing humoral immunity. By tracking the fate of virus-specific B cells in vivo, we report that LCMV-specific B cells were rapidly deleted within a few days of persistent infection, and this deletion was completely reversed by blockade of type I interferon (IFN-I) signaling. Early interference with IFN-I signaling promoted survival and differentiation of LCMV-specific B cells, which accelerated the generation of neutralizing antibodies. This marked improvement in antiviral humoral immunity did not rely on the cessation of IFN-I signaling in B cells but on alterations in the virus-specific CD8+ T cell response. Using two-photon microscopy and in vivo calcium imaging, we observed that cytotoxic T lymphocytes (CTLs) productively engaged and killed LCMV-specific B cells in a perforin-dependent manner within the first few days of infection. Blockade of IFN-I signaling protected LCMV-specific B cells by promoting CTL dysfunction. Therapeutic manipulation of this pathway may facilitate efforts to promote humoral immunity during persistent viral infection in humans. Our findings illustrate how events that occur early after infection can disturb the resultant adaptive response and contribute to viral persistence.

  17. Activated RET/PTC oncogene elicits immediate early and delayed response genes in PC12 cells.

    Science.gov (United States)

    Califano, D; Monaco, C; de Vita, G; D'Alessio, A; Dathan, N A; Possenti, R; Vecchio, G; Fusco, A; Santoro, M; de Franciscis, V

    1995-07-06

    The expression of the receptor-like tyrosine kinase RET is associated with tumors, tissues or cell lines of neural crest origin. In addition RET products (Ret) are involved in determining cell fate during the differentiation of the enteric nervous system and during renal organogenesis. However, as yet, no direct evidence exists to indicate that the Ret kinase activity might interfere in a specific way with cellular differentiation, or proliferation, of a neural crest derived cell line. By using two constitutively activated forms of RET (RET/PTC1 and RET/PTC3) in transient transfection experiments, we have obtained evidence that active RET could reprogramme the gene expression pattern in the rat pheochromocytoma PC12 cell line. Transcription driven by gene promoters, such as NGFI-A and vgf, which belong, respectively, to primary and delayed response genes to nerve growth factor (NGF), and by the neuron-specific enolase (NSE) promoter, is rapidly induced by the expression of activated RET oncogenes. This induction is not elicited in other non neural derived cell types tested. We also demonstrate that endogenous ras activity is required for RET induction of these neural markers. Finally, in the RET/PTC transfected PC12 cells, NGF is unable to induce further their transcription. This suggests that RET/PTC could share an intracellular signalling pathway with the NGF-receptor.

  18. Model of cell response to {\\alpha}-particle radiation

    CERN Document Server

    Liu, Longjian

    2012-01-01

    Starting from a general equation for organism (or cell system) growth and attributing additional cell death rate (besides the natural rate) to therapy, we derive an equation for cell response to {\\alpha} radiation. Different from previous models that are based on statistical theory, the present model connects the consequence of radiation with the growth process of a biosystem and each variable or parameter has meaning regarding the cell evolving process. We apply this equation to model the dose response for {\\alpha}-particle radiation. It interprets the results of both high and low linear energy transfer (LET) radiations. When LET is high, the additional death rate is a constant, which implies that the localized cells are damaged immediately and the additional death rate is proportional to the number of cells present. While at low LET, the additional death rate includes a constant term and a linear term of radiation dose, implying that the damage to some cell nuclei has a time accumulating effect. This model ...

  19. Further evidence for a human B cell activating factor distinct from IL-4.

    Science.gov (United States)

    Diu, A; Février, M; Mollier, P; Charron, D; Banchereau, J; Reinherz, E L; Thèze, J

    1990-01-01

    Supernatants from activated human T cell clones were previously shown to contain B cell-activating factor (BCAF), an activity which results in polyclonal resting B cell stimulation. In the present study, we investigate the relationship between this activity and human interleukin-4 which was also shown to act on resting B cells. The supernatant of the T cell clone TT9 contains IL-4 but anti-IL-4 antiserum does not affect the response of B cells as measured by thymidine uptake or cell volume increase. Furthermore, IL-4 induces Fc epsilon-receptor (CD23) expression on 30% of unstimulated human B cells, whereas BCAF-containing supernatants from clone P2, that do not contain detectable amounts of IL-4, promote B cell proliferation without inducing CD23 expression. Our results therefore establish that IL-4 and BCAF are distinct activities and suggest that they trigger different activation pathways in human B cells. In addition, culture of B cells with T cell supernatants for 72 hr induces a three- to fourfold increase in the expression of HLA-DR, -DP, and -DQ antigens in 50% of B cells. The addition of inhibiting concentrations of anti-IFN-gamma, LT, or IL-4 antisera to the cultures does not change these results. Finally, 30% of B cells cultured with T cell supernatants leave the G1 phase of the cell cycle and 20% reach mitosis. Taken together, our findings further support the existence of a B cell-activating factor responsible for the activation of resting human B cells.

  20. Ultrastructural evidence for differentiation in a human glioblastoma cell line treated with inhibitors of eicosanoid metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, D.E.; Anderson, K.M. (Rush Presbyterian St. Luke' s Medical Center, Chicago, IL (United States)); Seed, T.M. (Argonne National Lab., IL (United States))

    1990-01-01

    Human glioblastoma cells incubated in the presence of inhibitors of eicosanoid biosynthesis show decreased cellular proliferation without cytotoxicity. The authors studied the ultrastructural morphology of a human glioblastoma cell line cultured with nordihydroguaiaretic acid (NDGA), a lipoxygenase inhibitor, or 5,8,11,14-eicosatetraynoic acid, a cyclooxygenase and lipoxygenase inhibitor. When glioblastoma cells were treated for 3 days with antiproliferative concentrations of either agent, they shared many morphological characteristics, including evidence for increased astrocytic differentiation with only limited signs of toxicity. The inhibited glioma cells demonstrated an increase in the number and length of astrocytic processes containing greater numbers of glial filaments, and the NDGA-treated cells also demonstrated extensive lateral pseudopod formation along the processes. The glioblastoma cell shape also become more elongated, losing the usual nuclear lobularity and nuclear inclusions, especially in NDGA-treated cells. Many cytoplasmic organelles packed the cytosol of the inhibited glioma cells, including prominent Golgi apparatus, dilated smooth endoplasmic reticulum evolving into dilated vesicles, cytoplasmic vacuoles, and numerous concentric laminations. There was limited evidence for toxicity, however, as the mitochondria were more pleomorphic with some mitochondrial distension and disruption of the cristae along with an increase in cytoplasmic vacuolization. The authors conclude that the inhibitors of eicosanoid biosynthesis. NDGA and 5,8,11,14-eicosatetraynoic acid, not only suppress glioblastoma cell proliferation, but also include increased astrocytic differentiation.

  1. Nonimmune Cells Contribute to Crosstalk between Immune Cells and Inflammatory Mediators in the Innate Response to Trypanosoma cruzi Infection

    Directory of Open Access Journals (Sweden)

    Maria Pilar Aoki

    2012-01-01

    Full Text Available Chagas myocarditis, which is caused by infection with the intracellular parasite Trypanosoma cruzi, remains the major infectious heart disease worldwide. Innate recognition through toll-like receptors (TLRs on immune cells has not only been revealed to be critical for defense against T. cruzi but has also been involved in triggering the pathology. Subsequent studies revealed that this parasite activates nucleotide-binding oligomerization domain- (NOD-like receptors and several particular transcription factors in TLR-independent manner. In addition to professional immune cells, T. cruzi infects and resides in different parenchyma cells. The innate receptors in nonimmune target tissues could also have an impact on host response. Thus, the outcome of the myocarditis or the inflamed liver relies on an intricate network of inflammatory mediators and signals given by immune and nonimmune cells. In this paper, we discuss the evidence of innate immunity to the parasite developed by the host, with emphasis on the crosstalk between immune and nonimmune cell responses.

  2. Responses of Cancer Cells Induced by Photodynamic Therapy

    Directory of Open Access Journals (Sweden)

    Toshihiro Kushibiki

    2013-01-01

    Full Text Available Photodynamic therapy (PDT involves the administration of a photosensitizer, followed by local irradiation of tumor tissues using a laser of an appropriate wavelength to activate the photosensitizer. Since multiple cellular signaling cascades are concomitantly activated in cancer cells exposed to the photodynamic effect, understanding the responses of cancer cells to PDT will aid in the development of new interventions. This review describes the possible cell-death signaling pathways initiated by PDT. In addition, we describe our latest findings regarding the induction of expression of miRNAs specific to apoptosis in cancer cells and the induction of antitumor immunity following PDT against cancer cells. A more detailed understanding of the molecular mechanisms related to PDT will potentially improve long-term survival of PDT treated patients.

  3. Biomaterial nanotopography-mediated cell responses: experiment and modeling

    Directory of Open Access Journals (Sweden)

    Lei Yang

    2014-10-01

    Full Text Available The rapid development of fabrication and processing technologies in the past two decades has enabled researchers to introduce nanoscale features into materials which, interestingly, have been shown to greatly regulate the behavior and fate of biological cells. In particular, important cell responses (such as adhesion, proliferation, differentiation, migration, and filopodial growth have all been correlated with material nanotopography. Given its great potential, intensive efforts have been made, both experimentally and theoretically, to understand why and how cells respond to nanoscale surface features, and this article reviews recent progress in this field. Specifically, a brief overview on the fabrication and modification techniques to create nanotopography on different materials is given first. After that, a summary of important experimental findings on the mediation of nanoscale surface topography on the behavior of various cells, as well as the underlying mechanism, is provided. Finally, both classical and recently developed approaches for modeling nanotopography-mediated cell adhesion and filopodial growth are reviewed.

  4. Point: clarifying policy evidence with potential-outcomes thinking--beyond exposure-response estimation in air pollution epidemiology.

    Science.gov (United States)

    Zigler, Corwin Matthew; Dominici, Francesca

    2014-12-15

    The regulatory environment surrounding policies to control air pollution warrants a new type of epidemiologic evidence. Whereas air pollution epidemiology has typically informed policies with estimates of exposure-response relationships between pollution and health outcomes, these estimates alone cannot support current debates surrounding the actual health effects of air quality regulations. We argue that directly evaluating specific control strategies is distinct from estimating exposure-response relationships and that increased emphasis on estimating effects of well-defined regulatory interventions would enhance the evidence that supports policy decisions. Appealing to similar calls for accountability assessment of whether regulatory actions impact health outcomes, we aim to sharpen the analytic distinctions between studies that directly evaluate policies and those that estimate exposure-response relationships, with particular focus on perspectives for causal inference. Our goal is not to review specific methodologies or studies, nor is it to extoll the advantages of "causal" versus "associational" evidence. Rather, we argue that potential-outcomes perspectives can elevate current policy debates with more direct evidence of the extent to which complex regulatory interventions affect health. Augmenting the existing body of exposure-response estimates with rigorous evidence of the causal effects of well-defined actions will ensure that the highest-level epidemiologic evidence continues to support regulatory policies.

  5. Regulation of germinal center responses, memory B cells and plasma cell formation-an update.

    Science.gov (United States)

    Corcoran, Lynn M; Tarlinton, David M

    2016-04-01

    Progress in understanding humoral immunity has been accelerated by the powerful experimental approaches of genetics, genomics and imaging. Excellent reviews of these advances appeared in 2015 in celebration of the 50th anniversary of the discovery of B cell and T cell lineages in the chicken. Here we provide a contemporary model of B cell differentiation, highlighting recent publications illuminating germinal center (GC), memory B cell and antibody-secreting plasma cell biology. The important contributions of CD4T cells to antibody responses have been thoroughly reviewed elsewhere.

  6. Pellino-1 Selectively Regulates Epithelial Cell Responses to Rhinovirus

    NARCIS (Netherlands)

    Bennett, Julie A; Prince, Lynne R; Parker, Lisa C; Stokes, Clare A; de Bruin, Harold G; van den Berge, Maarten; Heijink, Irene H; Whyte, Moira K; Sabroe, Ian

    2012-01-01

    Pellino-1 has recently been identified as a regulator of interleukin-1 (IL-1) signaling, but its roles in regulation of responses of human cells to human pathogens are unknown. We investigated the potential roles of Pellino-1 in the airways. We show for the first time that Pellino-1 regulates respon

  7. Pellino-1 selectively regulates epithelial cell responses to rhinovirus

    NARCIS (Netherlands)

    Bennett, Julie A; Prince, Lynne R; Parker, Lisa C; Stokes, Clare A; de Bruin, Harold G; van den Berge, Maarten; Heijink, Irene H; Whyte, Moira K; Sabroe, Ian

    2012-01-01

    Pellino-1 has recently been identified as a regulator of interleukin-1 (IL-1) signaling, but its roles in regulation of responses of human cells to human pathogens are unknown. We investigated the potential roles of Pellino-1 in the airways. We show for the first time that Pellino-1 regulates respon

  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. Innate immune response to pulmonary contusion: identification of cell type-specific inflammatory responses.

    Science.gov (United States)

    Hoth, J Jason; Wells, Jonathan D; Yoza, Barbara K; McCall, Charles E

    2012-04-01

    Lung injury from pulmonary contusion is a common traumatic injury, predominantly seen after blunt chest trauma, such as in vehicular accidents. The local and systemic inflammatory response to injury includes activation of innate immune receptors, elaboration of a variety of inflammatory mediators, and recruitment of inflammatory cells to the injured lung. Using a mouse model of pulmonary contusion, we had previously shown that innate immune Toll-like receptors 2 and 4 (TLR2 and TLR4) mediate the inflammatory response to lung injury. In this study, we used chimeric mice generated by adoptive bone marrow transfer between TLR2 or TLR4 and wild-type mice. We found that, in the lung, both bone marrow-derived and nonmyeloid cells contribute to TLR-dependent inflammatory responses after injury in a cell type-specific manner. We also show a novel TLR2-dependent injury mechanism that is associated with enhanced airway epithelial cell apoptosis and increased pulmonary FasL and Fas expression in the lungs from injured mice. Thus, in addition to cardiopulmonary physiological dysfunction, cell type-specific TLR and their differential response to injury may provide novel specific targets for management of patients with pulmonary contusion.

  10. 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.

  11. Mechanical Response of Single Plant Cells to Cell Poking: A Numerical Simulation Model

    Institute of Scientific and Technical Information of China (English)

    Rong Wang; Qun-Ying Jiao; De-Qiang Wei

    2006-01-01

    Cell poking is an experimental technique that is widely used to study the mechanical properties of plant cells. A full understanding of the mechanical responses of plant cells to poking force is helpful for experimental work. The aim of this study was to numerically investigate the stress distribution of the cell wall,cell turgor, and deformation of plant cells in response to applied poking force. Furthermore, the locations damaged during poking were analyzed. The model simulates cell poking, with the cell treated as a spherical,homogeneous, isotropic elastic membrane, filled with incompressible, highly viscous liquid. Equilibrium equations for the contact region and the non-contact regions were determined by using membrane theory.The boundary conditions and continuity conditions for the solution of the problem were found. The forcedeformation curve, turgor pressure and tension of the cell wall under cell poking conditions were obtained.The tension of the cell wall circumference was larger than that of the meridian. In general, maximal stress occurred at the equator around. When cell deformation increased to a certain level, the tension at the poker tip exceeded that of the equator. Breakage of the cell wall may start from the equator or the poker tip,depending on the deformation. A nonlinear model is suitable for estimating turgor, stress, and stiffness,and numerical simulation is a powerful method for determining plant cell mechanical properties.

  12. Homeostatic responses by surviving cortical pyramidal cells in neurodegenerative tauopathy.

    Science.gov (United States)

    Crimins, Johanna L; Rocher, Anne B; Peters, Alan; Shultz, Penny; Lewis, Jada; Luebke, Jennifer I

    2011-11-01

    Cortical neuron death is prevalent by 9 months in rTg(tau(P301L))4510 tau mutant mice (TG) and surviving pyramidal cells exhibit dendritic regression and spine loss. We used whole-cell patch-clamp recordings to investigate the impact of these marked structural changes on spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs) of layer 3 pyramidal cells in frontal cortical slices from behaviorally characterized TG and non-transgenic (NT) mice at this age. Frontal lobe function of TG mice was intact following a short delay interval but impaired following a long delay interval in an object recognition test, and cortical atrophy and cell loss were pronounced. Surviving TG cells had significantly reduced dendritic diameters, total spine density, and mushroom spines, yet sEPSCs were increased and sIPSCs were unchanged in frequency. Thus, despite significant regressive structural changes, synaptic responses were not reduced in TG cells, indicating that homeostatic compensatory mechanisms occur during progressive tauopathy. Consistent with this idea, surviving TG cells were more intrinsically excitable than NT cells, and exhibited sprouting of filopodia and axonal boutons. Moreover, the neuropil in TG mice showed an increased density of asymmetric synapses, although their mean size was reduced. Taken together, these data indicate that during progressive tauopathy, cortical pyramidal cells compensate for loss of afferent input by increased excitability and establishment of new synapses. These compensatory homeostatic mechanisms may play an important role in slowing the progression of neuronal network dysfunction during neurodegenerative tauopathies.

  13. New aspects of gravity responses in plant cells.

    Science.gov (United States)

    Hoson, Takayuki; Soga, Kouichi

    2003-01-01

    Plants show two distinct responses to gravity: gravity-dependent morphogenesis (gravimorphogenesis) and gravity resistance. In gravitropism, a typical mechanism of gravimorphogenesis, gravity is utilized as a signal to establish an appropriate form. The response has been studied in a gravity-free environment, where plant seedlings were found to perform spontaneous morphogenesis, termed automorphogenesis. Automorphogenesis consists of a change in growth direction and spontaneous curvature in dorsiventral directions. The spontaneous curvature is caused by a difference in the capacity of the cell wall to expand between the dorsal and the ventral sides of organs, which originates from the inherent structural anisotropy. Gravity resistance is a response that enables the plant to develop against the gravitational force. To resist the force, the plant constructs a tough body by increasing the cell wall rigidity that suppresses growth. The mechanical properties of the cell wall are changed by modification of the cell wall metabolism and cell wall environment, especially pH. In gravitropism, gravity is perceived by amyloplasts in statocytes, whereas gravity resistance may be mediated by mechanoreceptors on the plasma membrane.

  14. Functional analysis of the RNAi response in ovary-derived silkmoth Bm5 cells.

    Science.gov (United States)

    Kolliopoulou, Anna; Swevers, Luc

    2013-08-01

    Experiments of dsRNA-mediated gene silencing in lepidopteran insects in vivo are characterized by high variability although lepidopteran cell cultures have shown an efficient response to RNAi in transfection experiments. In order to identify the core RNAi factors that regulate the RNAi response of Lepidoptera, we employed the silkmoth ovary-derived Bm5 cells as a test system since this cell line is known to respond potently in silencing after dsRNA transfection. Two parallel approaches were used; involving knock-down of the core RNAi genes or over-expression of the main siRNA pathway factors, in order to study possible inhibition or stimulation of the RNAi silencing response, respectively. Components from all three main small RNA pathways (BmAgo-1 for miRNA, BmAgo-2/BmDcr-2 for siRNA, and BmAgo-3 for piRNA) were found to be involved in the RNAi response that is triggered by dsRNA. Since BmAgo-3, a factor in the piRNA pathway that functions independent of Dicer in Drosophila, was identified as a limiting factor in the RNAi response, sense and antisense ssRNA was also tested to induce gene silencing but proved to be ineffective, suggesting a dsRNA-dependent role for BmAgo-3 in Bombyx mori. After efficient over-expression of the main siRNA factors, immunofluorescence staining revealed a predominant cytoplasmic localization in Bm5 cells. This is the first study in Lepidoptera to provide evidence for possible overlapping of all three known small RNA pathways in the regulation of the dsRNA-mediated silencing response using transfected B. mori-derived Bm5 cells as experimental system.

  15. Renal cell carcinoma: complete pathological response in a patient with gastric metastasis of renal cell carcinoma.

    Science.gov (United States)

    García-Campelo, Rosario; Quindós, Maria; Vázquez, Diana Dopico; López, Margarita Reboredo; Carral, Alberto; Calvo, Ovidio Fernández; Soto, José Manuel Rois; Grande, Enrique; Durana, Jesús; Antón-Aparicio, Luis Miguel

    2010-01-01

    A 75-year-old-man, with a 2-month history of abdominal pain, underwent a standard diagnostic workup that included a CT scan that showed a large right renal mass and subcentimeter nodes in the right and left lung lobes. In December 2003, the patient underwent right nephrectomy with adrenalectomy and a diagnosis of renal cell carcinoma (pT3N0M0 stage) was made. No further treatment was proposed and patient was followed up regularly. In October 2006, the annual gastrointestinal endoscopy showed asymptomatic multilobulated and polypoid masses in the gastric fundus and gastric body that corresponded to metastasis of the renal carcinoma that had been resected three years ago. Surgical treatment was refused and oral treatment with sunitinib (50 mg/day consecutively for 4 weeks followed by 2 weeks off) was initiated. Patient completed one cycle and development of acute toxicity (grade 3 asthenia, anorexia and mucositis) led to treatment interruption. After recovering from acute toxicity, the patient was proposed to reinitiate treatment with dose reduction, but he refused any medical treatment. At the follow-up visit, three months later, the gastrointestinal endoscopy showed four unspecific 2 mm nodules without malignant evidence. The whole-body CT did not reveal any other abnormality except for the known lung nodes. PET scan six months after treatment confirmed complete gastric response.

  16. Chitosan Interferon-γ Nanogene Therapy for Lung Disease: Modulation of T-Cell and Dendritic Cell Immune Responses

    Directory of Open Access Journals (Sweden)

    Kong Xiaoyuan

    2008-09-01

    Full Text Available The use of chitosan nanoparticles as carriers for expression plasmids represents a major improvement in gene expression technology. We demonstrated previously that treatment with chitosan interferon-γ (IFN-γ plasmid deoxyribonucleic acid (DNA nanoparticles (chitosan interferon-γ nanogene [CIN] led to in situ production of IFN-γ and a reduction in inflammation and airway reactivity in mice, but the mechanism underlying the immunomodulatory effects of CIN remains unclear. In this report, the effect of CIN treatment on the immune responses of CD8+ T cells and dendritic cells was examined in a BALB/c mouse model of ovalbumin (OVA-induced allergic asthma. OT1 mice (OVA-T cell receptor [TCR] transgenic were also used to test the effects of CIN on OVA-specific CD8+ T cells. CIN treatment caused a reduction in IFN-γ production in a subpopulation of OVA-specific CD8+ T cells cultured in vitro in the presence of OVA. CIN also reduced apoptosis of the CD8+ T cells. Examination of dendritic cells from lung and lymph nodes indicated that CIN treatment decreased their antigen-presenting activity, as evident from the reduction in CD80 and CD86 expression. Furthermore, CIN treatment significantly decreased the number of CD11c+b+ dendritic cells in lymph nodes, suggesting that endogenous IFN-γ expression may immunomodulate dendritic cell migration and activation. CIN therapy results in a reduction in proinflammatory CD8+ T cells and decreases the number and antigen-presenting activity of dendritic cells.

  17. Uncoupling between inflammatory and fibrotic responses to silica: evidence from MyD88 knockout mice.

    Directory of Open Access Journals (Sweden)

    Sandra Lo Re

    Full Text Available The exact implication of innate immunity in granuloma formation and irreversible lung fibrosis remains to be determined. In this study, we examined the lung inflammatory and fibrotic responses to silica in MyD88-knockout (KO mice. In comparison to wild-type (WT mice, we found that MyD88-KO animals developed attenuated lung inflammation, neutrophil accumulation and IL-1β release in response to silica. Granuloma formation was also less pronounced in MyD88-KO mice after silica. This limited inflammatory response was not accompanied by a concomitant attenuation of lung collagen accumulation after silica. Histological analyses revealed that while pulmonary fibrosis was localized in granulomas in WT animals, it was diffusely distributed throughout the parenchyma in MyD88-KO mice. Robust collagen accumulation was also observed in mice KO for several other components of innate immunity (IL-1R, IL-1, ASC, NALP3, IL-18R, IL-33R, TRIF, and TLR2-3-4,. We additionally show that pulmonary fibrosis in MyD88-KO mice was associated with the accumulation of pro-fibrotic regulatory T lymphocytes (T regs and pro-fibrotic cytokine expression (TGF-β, IL-10 and PDGF-B, not with T helper (Th 17 cell influx. Our findings indicate that the activation of MyD88-related innate immunity is central in the establishment of particle-induced lung inflammatory and granuloma responses. The development of lung fibrosis appears uncoupled from inflammation and may be orchestrated by a T reg-associated pathway.

  18. The stringent response and cell cycle arrest in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Daniel J Ferullo

    2008-12-01

    Full Text Available The bacterial stringent response, triggered by nutritional deprivation, causes an accumulation of the signaling nucleotides pppGpp and ppGpp. We characterize the replication arrest that occurs during the stringent response in Escherichia coli. Wild type cells undergo a RelA-dependent arrest after treatment with serine hydroxamate to contain an integer number of chromosomes and a replication origin-to-terminus ratio of 1. The growth rate prior to starvation determines the number of chromosomes upon arrest. Nucleoids of these cells are decondensed; in the absence of the ability to synthesize ppGpp, nucleoids become highly condensed, similar to that seen after treatment with the translational inhibitor chloramphenicol. After induction of the stringent response, while regions corresponding to the origins of replication segregate, the termini remain colocalized in wild-type cells. In contrast, cells arrested by rifampicin and cephalexin do not show colocalized termini, suggesting that the stringent response arrests chromosome segregation at a specific point. Release from starvation causes rapid nucleoid reorganization, chromosome segregation, and resumption of replication. Arrest of replication and inhibition of colony formation by ppGpp accumulation is relieved in seqA and dam mutants, although other aspects of the stringent response appear to be intact. We propose that DNA methylation and SeqA binding to non-origin loci is necessary to enforce a full stringent arrest, affecting both initiation of replication and chromosome segregation. This is the first indication that bacterial chromosome segregation, whose mechanism is not understood, is a step that may be regulated in response to environmental conditions.

  19. B cell activating factor (BAFF) selects IL-10(-)B cells over IL-10(+)B cells during inflammatory responses.

    Science.gov (United States)

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

    2017-02-12

    B cell activating factor (BAFF) regulates B cell maturation, survival, function, and plays a critical pathogenic role in autoimmune diseases. It remains unclear how BAFF affects IL-10(-)B cells versus regulatory B cells (Bregs) in inflammatory responses. In this study, we found that IL-10-expressing Bregs decreased in lupus-prone MRL/lpr mice and experimental allergic encephalomyelitis (EAE) mice. On blockade of the effects of BAFF with TACI-IgG, IL-10(+) Bregs were upregulated in MRL/lpr and EAE mice. In addition, BAFF expanded IL-10(+)B cells over IL-10(-)B cells under noninflammatory conditions in vitro, whereas it expanded IL-10(-)B cells over IL-10(+)B cells during inflammatory responses, such as stimulation with autoantigen and LPS. Finally, the selection of IL-10(-)B cells over IL-10(+)B cells by BAFF was dependent on BAFF receptors (BAFFR, TACI, and BCMA) that were upregulated by inflammatory responses. This study suggests that BAFF selects IL-10(-)B cells over IL-10(+) regulatory B cells via BAFF receptors in inflammatory responses.

  20. Permafrost response to last interglacial warming: field evidence from non-glaciated Yukon and Alaska

    Science.gov (United States)

    Reyes, Alberto V.; Froese, Duane G.; Jensen, Britta J. L.

    2010-11-01

    We present stratigraphic observations from three sites in eastern Beringia - Ch'ijee's Bluff in northern Yukon and nearby exposures on the Old Crow River, the Palisades on the Yukon River in Alaska, and placer mining exposures at Thistle Creek in west-central Yukon - which provide insight into the response of permafrost to regional warming during the last interglaciation. Chronology is based on the presence of Old Crow tephra, an important regional stratigraphic marker that dates to late Marine Isotope Stage 6, supplemented by paleoecology and non-finite 14C ages on wood-rich organic silts. Old Crow tephra overlies several relict ice wedges at the Palisades and Thistle Creek, indicating that permafrost at these sites did not thaw completely during the last interglaciation. Prominent deposits of last interglacial wood-rich organic silt are present at multiple sites in eastern Beringia, and probably represent accumulations of reworked forest vegetation due to thaw slumping or deposition into thermokarst ponds or depressions. Consistent stratigraphic relations between these deposits, Old Crow tephra, and ice wedge pseudomorphs at our three study sites, and at least six other sites in eastern Beringia, suggest that thaw of shallow permafrost was widespread during the last interglaciation. Limited stratigraphic evidence suggests that thaw was probably on the order of meters, rather than 10s of meters. The ubiquity of shallow permafrost degradation during the last interglaciation suggests that current ground warming may foreshadow widespread near-surface thaw under even modest future warming scenarios. However, the persistence of relict pre-last interglacial ice wedges highlights the potential for the regional antiquity of discontinuous permafrost, and provides compelling field evidence for the long-term resilience of deep permafrost during sustained periods of warmer-than-present climate.

  1. Exercise, Abdominal Obesity, Skeletal Muscle, and Metabolic Risk: Evidence for a Dose Response

    Science.gov (United States)

    Slentz, Cris A.; Houmard, Joseph A.; Kraus, William E.

    2013-01-01

    The obese are at increased risk for cardiovascular disease and type 2 diabetes. However, some who are obese have no metabolic abnormalities. So, it is not adipose tissue per se, but perhaps where it is located that is important for determining metabolic consequences. Regular exercise is known to reduce risk for metabolic disease through numerous mechanisms. The purpose of this report is to highlight some of the efficacy-based data on the effects of exercise (and also a sedentary lifestyle) on abdominal obesity, visceral fat, and metabolic risk. We also discuss how impaired fatty acid oxidation (FAO) in skeletal muscle may be related to both insulin resistance and a contributor to weight gain. In summary, it is evident that exercise in sufficient amounts can lead to substantial decreases in body weight, total body fat, and visceral fat. Additionally, evidence now supports the conclusion that there is a dose–response relationship between exercise amount and these changes, i.e., more exercise leads to additional benefits. Additionally, there are a number of important cardiometabolic risk factors that were most favorably effected by moderate-intensity compared to vigorous-intensity exercise. Unfortunately, it is also apparent that in sedentary middle-aged men and women, short periods of physical inactivity lead to significant weight gain, substantial increases in visceral fat, and further metabolic deterioration. Finally, favorable modulation of mitochondrial oxidative capacity in skeletal muscle by exercise training may reduce a block for complete oxidation of fatty acids in muscle and thereby relieve a block to effective insulin signaling. PMID:19927142

  2. IDO2 Modulates T Cell-Dependent Autoimmune Responses through a B Cell-Intrinsic Mechanism.

    Science.gov (United States)

    Merlo, Lauren M F; DuHadaway, James B; Grabler, Samantha; Prendergast, George C; Muller, Alexander J; Mandik-Nayak, Laura

    2016-06-01

    Mechanistic insight into how adaptive immune responses are modified along the self-nonself continuum may offer more effective opportunities to treat autoimmune disease, cancer, and other sterile inflammatory disorders. Recent genetic studies in the KRN mouse model of rheumatoid arthritis demonstrate that the immunomodulatory molecule IDO2 modifies responses to self-antigens; however, the mechanisms involved are obscure. In this study, we show that IDO2 exerts a critical function in B cells to support the generation of autoimmunity. In experiments with IDO2-deficient mice, adoptive transplant experiments demonstrated that IDO2 expression in B cells was both necessary and sufficient to support robust arthritis development. IDO2 function in B cells was contingent on a cognate, Ag-specific interaction to exert its immunomodulatory effects on arthritis development. We confirmed a similar requirement in an established model of contact hypersensitivity, in which IDO2-expressing B cells are required for a robust inflammatory response. Mechanistic investigations showed that IDO2-deficient B cells lacked the ability to upregulate the costimulatory marker CD40, suggesting IDO2 acts at the T-B cell interface to modulate the potency of T cell help needed to promote autoantibody production. Overall, our findings revealed that IDO2 expression by B cells modulates autoimmune responses by supporting the cross talk between autoreactive T and B cells.

  3. Neural progenitor cells from human induced pluripotent stem cells generated less autogenous immune response.

    Science.gov (United States)

    Huang, Ke; Liu, PengFei; Li, Xiang; Chen, ShuBin; Wang, LiHui; Qin, Li; Su, ZhengHui; Huang, WenHao; Liu, Juli; Jia, Bei; Liu, Jie; Cai, JingLei; Pei, DuanQing; Pan, GuangJin

    2014-02-01

    The breakthrough development of induced pluripotent stem cells (iPSCs) raises the prospect of patient-specific treatment for many diseases through the replacement of affected cells. However, whether iPSC-derived functional cell lineages generate a deleterious immune response upon auto-transplantation remains unclear. In this study, we differentiated five human iPSC lines from skin fibroblasts and urine cells into neural progenitor cells (NPCs) and analyzed their immunogenicity. Through co-culture with autogenous peripheral blood mononuclear cells (PBMCs), we showed that both somatic cells and iPSC-derived NPCs do not stimulate significant autogenous PBMC proliferation. However, a significant immune reaction was detected when these cells were co-cultured with allogenous PBMCs. Furthermore, no significant expression of perforin or granzyme B was detected following stimulation of autogenous immune effector cells (CD3(+)CD8(-) T cells, CD3(+)CD8(+) T cells or CD3(-)CD56(+) NK cells) by NPCs in both PBMC and T cell co-culture systems. These results suggest that human iPSC-derived NPCs may not initiate an immune response in autogenous transplants, and thus set a base for further preclinical evaluation of human iPSCs.

  4. Detecting Antigen-Specific T Cell Responses: From Bulk Populations to Single Cells

    Directory of Open Access Journals (Sweden)

    Chansavath Phetsouphanh

    2015-08-01

    Full Text Available A new generation of sensitive T cell-based assays facilitates the direct quantitation and characterization of antigen-specific T cell responses. Single-cell analyses have focused on measuring the quality and breadth of a response. Accumulating data from these studies demonstrate that there is considerable, previously-unrecognized, heterogeneity. Standard assays, such as the ICS, are often insufficient for characterization of rare subsets of cells. Enhanced flow cytometry with imaging capabilities enables the determination of cell morphology, as well as the spatial localization of the protein molecules within a single cell. Advances in both microfluidics and digital PCR have improved the efficiency of single-cell sorting and allowed multiplexed gene detection at the single-cell level. Delving further into the transcriptome of single-cells using RNA-seq is likely to reveal the fine-specificity of cellular events such as alternative splicing (i.e., splice variants and allele-specific expression, and will also define the roles of new genes. Finally, detailed analysis of clonally related antigen-specific T cells using single-cell TCR RNA-seq will provide information on pathways of differentiation of memory T cells. With these state of the art technologies the transcriptomics and genomics of Ag-specific T cells can be more definitively elucidated.

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

    NARCIS (Netherlands)

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

    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 cho

  6. 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.

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

    Science.gov (United States)

    Budagovsky, A. V.; Solovykh, N. V.; Budagovskaya, O. N.; Budagovsky, I. A.

    2015-04-01

    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 (λmax = 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 Lcoh and the correlation radius rcor 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.

  8. 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)

  9. Functional Signatures of Human CD4 and CD8 T Cell Responses to Mycobacterium tuberculosis.

    Science.gov (United States)

    Prezzemolo, Teresa; Guggino, Giuliana; La Manna, Marco Pio; Di Liberto, Diana; Dieli, Francesco; Caccamo, Nadia

    2014-01-01

    With 1.4 million deaths and 8.7 million new cases in 2011, tuberculosis (TB) remains a global health care problem and together with HIV and Malaria represents one of the three infectious diseases world-wide. Control of the global TB epidemic has been impaired by the lack of an effective vaccine, by the emergence of drug-resistant forms of Mycobacterium tuberculosis (Mtb) and by the lack of sensitive and rapid diagnostics. It is estimated, by epidemiological reports, that one third of the world's population is latently infected with Mtb, but the majority of infected individuals develop long-lived protective immunity, which controls and contains Mtb in a T cell-dependent manner. Development of TB disease results from interactions among the environment, the host, and the pathogen, and known risk factors include HIV co-infection, immunodeficiency, diabetes mellitus, overcrowding, malnutrition, and general poverty; therefore, an effective T cell response determines whether the infection resolves or develops into clinically evident disease. Consequently, there is great interest in determining which T cells subsets mediate anti-mycobacterial immunity, delineating their effector functions. On the other hand, many aspects remain unsolved in understanding why some individuals are protected from Mtb infection while others go on to develop disease. Several studies have demonstrated that CD4(+) T cells are involved in protection against Mtb, as supported by the evidence that CD4(+) T cell depletion is responsible for Mtb reactivation in HIV-infected individuals. There are many subsets of CD4(+) T cells, such as T-helper 1 (Th1), Th2, Th17, and regulatory T cells (Tregs), and all these subsets co-operate or interfere with each other to control infection; the dominant subset may differ between active and latent Mtb infection cases. Mtb-specific-CD4(+) Th1 cell response is considered to have a protective role for the ability to produce cytokines such as IFN-γ or TNF-α that

  10. Comparison of dendritic cell-mediated immune responses among canine malignant cells.

    Science.gov (United States)

    Tamura, Kyoichi; Arai, Hiroyoshi; Ueno, Emi; Saito, Chie; Yagihara, Hiroko; Isotani, Mayu; Ono, Kenichiro; Washizu, Tsukimi; Bonkobara, Makoto

    2007-09-01

    Dendritic cell (DC) vaccination is one of the most attractive immunotherapies for malignancies in dogs. To examine the differences in DC-mediated immune responses from different types of malignancies in dogs, we vaccinated dogs using autologous DCs pulsed with keyhole limpet hemocyanin (KLH) and cell lysate prepared from squamous cell carcinoma SCC2/88 (SCC-KLH-DC), histiocytic sarcoma CHS-5 (CHS-KLH-DC), or B cell leukemia GL-1 (GL-KLH-DC) in vitro. In vivo inductions of immune responses against these tumor cells were compared by the delayed-type hypersensitivity (DTH) skin test. The DTH response against SCC2/88 cells were observed in dogs vaccinated with autologous SCC-KLH-DC, while the response was undetectable against CHS-5 and GL-1 cells in dogs vaccinated with autologous CHS-KLH-DC and GL-KLH-DC. Skin biopsies taken from DTH challenge sites were then examined for immunohistochemistry, and recruitment of CD8 and CD4 T cells was detected at the site where SCC2/88 cells were inoculated in dogs vaccinated with SCC-KLH-DC. By contrast, neither CD8 nor CD4 T cell infiltration was found at the DTH challenge site in the dogs vaccinated with CHS-KLH-DC or GL-KLH-DC. These findings may reflect that the efficacy of immune induction by DC vaccination varies among tumor types and that immune responses could be inducible in squamous cell carcinoma. Our results encouraged further investigation of therapeutic vaccination for dogs with advanced squamous cell carcinoma in clinical trials.

  11. 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

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

    Science.gov (United States)

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

    2015-07-01

    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- or

  13. Evidence of T-cell mediated neuronal injury in stiff-person syndrome with anti-amphiphysin antibodies.

    Science.gov (United States)

    Poh, Mervyn Q W; Simon, Neil G; Buckland, Michael E; Salisbury, Elizabeth; Watson, Shaun

    2014-02-15

    Paraneoplastic stiff-person syndrome (SPS) has been associated with antibodies against amphiphysin. Current evidence supports a pathogenic role for anti-amphiphysin antibodies. A 74-year-old female was diagnosed with amphiphysin-associated paraneoplastic stiff-person syndrome and associated encephalomyelitis. She had initial response to IVIG, however her symptoms worsened after two months and were resistant to further treatment. Subsequently the patient died and a post-mortem was performed. Neuropathology revealed perivascular and parenchymal lymphocytic infiltrates, with neuronophagia mediated by CD8+ T cells and microglia in brainstem, spinal cord, and mesial temporal lobe structures. These findings suggest a pathogenic role of cytotoxic CD8+ T-cells, with potential implication for therapy of future patients.

  14. Differences in T-cell responses between Mycobacterium tuberculosis and Mycobacterium africanum-infected patients.

    Science.gov (United States)

    Tientcheu, Leopold D; Sutherland, Jayne S; de Jong, Bouke C; Kampmann, Beate; Jafali, James; Adetifa, Ifedayo M; Antonio, Martin; Dockrell, Hazel M; Ota, Martin O

    2014-05-01

    In The Gambia, Mycobacterium tuberculosis (Mtb) and Mycobacterium africanum (Maf) are major causes of tuberculosis (TB). Maf is more likely to cause TB in immune suppressed individuals, implying differences in virulence. Despite this, few studies have assessed the underlying immunity to the two pathogens in human. In this study, we analyzed T-cell responses from 19 Maf- and 29 Mtb-infected HIV-negative patients before and after TB chemotherapy following overnight stimulation of whole blood with TB-specific antigens. Before treatment, percentages of early secreted antigenic target-6(ESAT-6)/culture filtrate protein-10(CFP-10) and purified protein derivative-specific single-TNF-α-producing CD4(+) and CD8(+) T cells were significantly higher while single-IL-2-producing T cells were significantly lower in Maf- compared with Mtb-infected patients. Purified protein derivative-specific polyfunctional CD4(+) T cells frequencies were significantly higher before than after treatment, but there was no difference between the groups at both time points. Furthermore, the proportion of CD3(+) CD11b(+) T cells was similar in both groups pretreatment, but was significantly lower with higher TNF-α, IL-2, and IFN-γ production in Mtb- compared with that of Maf-infected patients posttreatment. Our data provide evidence of differences in T-cell responses to two mycobacterial strains with differing virulence, providing some insight into TB pathogenesis with different Mtb strains that could be prospectively explored as biomarkers for TB protection or susceptibility.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Responsive hydrogels produced via organic sol-gel chemistry for cell culture applications.

    Science.gov (United States)

    Patil, Smruti; Chaudhury, Pulkit; Clarizia, Lisa; McDonald, Melisenda; Reynaud, Emmanuelle; Gaines, Peter; Schmidt, Daniel F

    2012-08-01

    In this study, we report the synthesis of novel environmentally responsive polyurea hydrogel networks prepared via organic sol-gel chemistry and demonstrate that the networks can stabilize pH while releasing glucose both in simple aqueous media and in mammalian cell culture settings. Hydrogel formulations have been developed based on the combination of an aliphatic triisocyanate with pH-insensitive amine functional polyether and pH-sensitive poly(ethyleneimine) segments in a minimally toxic solvent suitable for the sol-gel reaction. The polyether component of the polyurea network is sufficiently hydrophilic to give rise to some level of swelling independent of environmental pH, while the poly(ethyleneimine) component contains tertiary amine groups providing pH sensitivity to the network in the form of enhanced swelling and release under acidic conditions. The reaction of these materials to form a network is rapid and requires no catalyst. The resultant material exhibits the desired pH-responsive swelling behavior and demonstrates its ability to simultaneously neutralize lactic acid and release glucose in both cell-free culture media and mammalian cell culture, with no detectable evidence of cytotoxicity or changes in cell behavior, in the case of either SA-13 human hybridomas or mouse embryonic stem cells. Furthermore, pH is observed to have a clear effect on the rate at which glucose is released from the hydrogel network. Such characteristics promise to maintain a favorable cell culture environment in the absence of human intervention.

  17. 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.

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

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    Klier Ulrike

    2011-09-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusion 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

  19. How States are Implementing Evidence-Based Teen Pregnancy Prevention Programs Through the Personal Responsibility Education Program.

    OpenAIRE

    Susan Zief; Rachel Shapiro; Debra Strong

    2014-01-01

    Congress created the Personal Responsibility Education Program (PREP), an initiative to fund evidence-based teen pregnancy prevention programs, in 2010 to help reduce teen pregnancies and their negative consequences. The evaluation will expand the knowledge base on teen pregnancy prevention programs and help to identify decisions, successes, and challenges involved in replicating, adapting, and scaling up evidence-based programs. This issue brief documents key decisions state grantees made ab...

  20. No evidence of altered alveolar macrophage polarization, but reduced expression of TLR2, in bronchoalveolar lavage cells in sarcoidosis

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    Wikén Maria

    2010-09-01

    Full Text Available Abstract Background Sarcoidosis is a granulomatous inflammatory disease, possibly of infectious aetiology. We aimed to investigate whether the degree of functional polarization of alveolar macrophages (AMs, or Toll-like receptor (TLR expression, is associated with sarcoidosis or with distinct clinical manifestations of this disease. Methods Total BAL cells (cultured four or 24 h in medium, or stimulated 24 h with LPS from 14 patients and six healthy subjects, sorted AMs from 22 patients (Löfgren's syndrome n = 11 and 11 healthy subjects, and sorted CD4+ T cells from 26 patients (Löfgren's syndrome n = 13 and seven healthy subjects, were included. Using real-time PCR, the relative gene expression of IL-10, IL-12p35, IL-12p40, IL-23p19, CCR2, CCR7, iNOS, CXCL10, CXCL11, CXCL16, CCL18, CCL20, CD80, and CD86, and innate immune receptors TLR2, TLR4, and TLR9, was quantified in sorted AMs, and for selected genes in total BAL cells, while IL-17A was quantified in T cells. Results We did not find evidence of a difference with regard to alveolar macrophage M1/M2 polarization between sarcoidosis patients and healthy controls. TLR2 gene expression was significantly lower in sorted AMs from patients, particular in Löfgren's patients. CCL18 gene expression in AMs was significantly higher in patients compared to controls. Additionally, the IL-17A expression was lower in Löfgren's patients' CD4+ T cells. Conclusions Overall, there was no evidence for alveolar macrophage polarization in sarcoidosis. However, there was a reduced TLR2 mRNA expression in patients with Löfgren's syndrome, which may be of relevance for macrophage interactions with a postulated sarcoidosis pathogen, and for the characteristics of the ensuing T cell response.

  1. 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.

  2. Ultrastructural Evidence of Exosome Secretion by Progenitor Cells in Adult Mouse Myocardium and Adult Human Cardiospheres

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    Lucio Barile

    2012-01-01

    Full Text Available The demonstration of beneficial effects of cell therapy despite the persistence of only few transplanted cells in vivo suggests secreted factors may be the active component of this treatment. This so-called paracrine hypothesis is supported by observations that culture media conditioned by progenitor cells contain growth factors that mediate proangiogenic and cytoprotective effects. Cardiac progenitor cells in semi-suspension culture form spherical clusters (cardiospheres that deliver paracrine signals to neighboring cells. A key component of paracrine secretion is exosomes, membrane vesicles that are stored intracellularly in endosomal compartments and are secreted when these structures fuse with the cell plasma membrane. Exosomes have been identified as the active component of proangiogenic effects of bone marrow CD34+ stem cells in mice and the regenerative effects of embryonic mesenchymal stem cells in infarcted hearts in pigs and mice. Here, we provide electron microscopic evidence of exosome secretion by progenitor cells in mouse myocardium and human cardiospheres. Exosomes are emerging as an attractive vector of paracrine signals delivered by progenitor cells. They can be stored as an “off-the-shelf” product. As such, exosomes have the potential for circumventing many of the limitations of viable cells for therapeutic applications in regenerative medicine.

  3. Helper role of NK cells during the induction of anticancer responses by dendritic cells.

    Science.gov (United States)

    Kalinski, Pawel; Giermasz, Adam; Nakamura, Yutaro; Basse, Per; Storkus, Walter J; Kirkwood, John M; Mailliard, Robbie B

    2005-02-01

    Recent reports demonstrate that natural killer (NK) cells and dendritic cells (DC) support each other's activity in a positive feedback. We observed that activated NK cells induce the maturation of DCs into stable type-1 polarized DCs (DC1), characterized by up to 100-fold enhanced ability to produce IL-12p70 in response to subsequent interaction with Th cells. DC1 induction depends on NK cell-produced IFN-gamma and TNF-alpha, with a possible involvement of additional factors. DC1, induced by NK cells or by NK cell-related soluble factors, are stable, resistant to tumor-related suppressive factors, and show strongly enhanced ability to induce Th1 and CTL responses. In analogy to resting T cells, the induction of "helper" function of NK cells relies on a two-signal activation paradigm. While NKG2D-dependent tumor cell recognition is sufficient to induce the cytotoxic "effector" function of NK cells, the induction of "NK cell help" requires additional signals from type-1 IFNs, products of virally-infected cells, or from IL-2. Compared to non-polarized DCs currently-used in clinical trials, DC1s act as superior inducers of anti-cancer CTL responses during in vitro sensitization. The current data provides rationale for the clinical use of DC1s in cancer and chronic infections (such as HIV), as a new generation DC-based vaccines, uniquely combining fully mature DC status with an elevated, rather than "exhausted" ability to produce bioactive IL-12p70. We are currently implementing stage I/II clinical trials, testing the effectiveness of DC1s induced by NK cells or by NK cell-related factors, as therapeutic vaccines against melanoma.

  4. Evidences for involvement of endogenous cAMP in Arabidopsis defense responses to Verticillium toxins

    Institute of Scientific and Technical Information of China (English)

    Jing JIANG; Ling Wen FAN; Wei Hua WU

    2005-01-01

    Although there were reports suggesting the involvement of endogenous cAMP in plant defense signaling cascades,there is no direct evidence supporting this notion yet and the detailed mechanism is unclear. In the present study, we have used pathogenic fungi Verticillium dahliae and Arabidopsis plants as a model system of plant-microb interaction to demonstrate the function of endogenous cAMP in Arabidopsis defense responses. Both V. dahliae inoculation and Verticillium toxins injection induced typical "wilt" symptoms in Arabidopsis seedlings. When either 8-Br-AMP (a membrane permeable cAMP analogue) or salicylic acid (SA) was applied to Arabidopsis, the plants became resistant to V. dahliae toxins. However, addition of 8-Br-AMP did not increase the resistance of Arabidopsis transgenic plants deficient in SA to the toxins, suggesting that cAMP might act upstream of SA in plant defense signaling pathway.Indeed, 8-Br-cAMP and forskolin, an activator of adenylyl cyclase, significantly stimulated the endogenous SA level in plants, whereas DDA, an inhibitor of adenylyl cyclase dramatically reduced toxin-induced SA increase. Both the endogenous cAMP and SA increased significantly in Arabidopsis seedlings treated with toxins. Furthermore, transcription level of pathogenesis-related protein 1 gene (PR1) was strongly induced by both 8-Br-cAMP and the toxin treatment. Taken together, our data demonstrate that endogenous cAMP is involved in plant defense responses against Verticilliumsecreted toxins by regulating the production of the known signal SA in plant defense pathway.

  5. Evidence for strain-specific differences in benzene toxicity as a function of host target cell susceptibility.

    Science.gov (United States)

    Neun, D J; Penn, A; Snyder, C A

    1992-01-01

    It has long been recognized that benzene exposure produces disparate toxic responses among different species or even among different strains within the same species. There is ample evidence that species- or strain-dependent differences in metabolic activity correlate with the disparate responses to benzene. However, bone marrow cells (the putative targets of benzene toxicity) may also exhibit species- or strain-dependent differences in susceptibility to the toxic effects of benzene. To investigate this hypothesis, two sets of companion experiments were performed. First, two strains of mice, Swiss Webster (SW) and C57B1/6J (C57), were exposed to 300 ppm benzene via inhalation and the effects of the exposures were determined on bone marrow cellularity and the development of bone marrow CFU-e (Colony Forming Unit-erythroid, an early red cell progenitor). Second, bone marrow cells from the same strains were exposed in vitro to five known benzene metabolites (1,4 benzoquinone, catechol, hydroquinone, muconic acid, and phenol) individually and in binary combinations. Benzene exposure, in vivo, reduced bone marrow cellularity and the development of CFU-e in both strains; however, reductions in both these endpoints were more severe in the SW strain. When bone marrow cells from the two strains were exposed in vitro to the five benzene metabolites individually, benzoquinone, hydroquinone, and catechol reduced the numbers of CFU-e in both strains in dose-dependent responses, phenol weakly reduced the numbers of the C57 CFU-e only and in a non-dose-dependent manner, and muconic acid was without effect on cells from either strain.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. 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

  7. Stress responses and replication of plasmids in bacterial cells

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    Wegrzyn Alicja

    2002-05-01

    Full Text Available Abstract Plasmids, DNA (or rarely RNA molecules which replicate in cells autonomously (independently of chromosomes as non-essential genetic elements, play important roles for microbes grown under specific environmental conditions as well as in scientific laboratories and in biotechnology. For example, bacterial plasmids are excellent models in studies on regulation of DNA replication, and their derivatives are the most commonly used vectors in genetic engineering. Detailed mechanisms of replication initiation, which is the crucial process for efficient maintenance of plasmids in cells, have been elucidated for several plasmids. However, to understand plasmid biology, it is necessary to understand regulation of plasmid DNA replication in response to different environmental conditions in which host cells exist. Knowledge of such regulatory processes is also very important for those who use plasmids as expression vectors to produce large amounts of recombinant proteins. Variable conditions in large-scale fermentations must influence replication of plasmid DNA in cells, thus affecting the efficiency of recombinant gene expression significantly. Contrary to extensively investigated biochemistry of plasmid replication, molecular mechanisms of regulation of plasmid DNA replication in response to various environmental stress conditions are relatively poorly understood. There are, however, recently published studies that add significant data to our knowledge on relations between cellular stress responses and control of plasmid DNA replication. In this review we focus on plasmids derived from bacteriophage λ that are among the best investigated replicons. Nevertheless, recent results of studies on other plasmids are also discussed shortly.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1986-03-01

    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.

  9. Oral microbial biofilm stimulation of epithelial cell responses.

    Science.gov (United States)

    Peyyala, Rebecca; Kirakodu, Sreenatha S; Novak, Karen F; Ebersole, Jeffrey L

    2012-04-01

    Oral bacterial biofilms trigger chronic inflammatory responses in the host that can result in the tissue destructive events of periodontitis. However, the characteristics of the capacity of specific host cell types to respond to these biofilms remain ill-defined. This report describes the use of a novel model of bacterial biofilms to stimulate oral epithelial cells and profile select cytokines and chemokines that contribute to the local inflammatory environment in the periodontium. Monoinfection biofilms were developed with Streptococcus sanguinis, Streptococcus oralis, Streptococcus gordonii, Actinomyces naeslundii, Fusobacterium nucleatum, and Porphyromonas gingivalis on rigid gas-permeable contact lenses. Biofilms, as well as planktonic cultures of these same bacterial species, were incubated under anaerobic conditions with a human oral epithelial cell line, OKF4, for up to 24h. Gro-1α, IL1α, IL-6, IL-8, TGFα, Fractalkine, MIP-1α, and IP-10 were shown to be produced in response to a range of the planktonic or biofilm forms of these species. P. gingivalis biofilms significantly inhibited the production of all of these cytokines and chemokines, except MIP-1α. Generally, the biofilms of all species inhibited Gro-1α, TGFα, and Fractalkine production, while F. nucleatum biofilms stimulated significant increases in IL-1α, IL-6, IL-8, and IP-10. A. naeslundii biofilms induced elevated levels of IL-6, IL-8 and IP-10. The oral streptococcal species in biofilms or planktonic forms were poor stimulants for any of these mediators from the epithelial cells. The results of these studies demonstrate that oral bacteria in biofilms elicit a substantially different profile of responses compared to planktonic bacteria of the same species. Moreover, certain oral species are highly stimulatory when in biofilms and interact with host cell receptors to trigger pathways of responses that appear quite divergent from individual bacteria.

  10. Blockade of Glutamine Synthetase Enhances Inflammatory Response in Microglial Cells

    Science.gov (United States)

    Palmieri, Erika M.; Menga, Alessio; Lebrun, Aurore; Hooper, Douglas C.; Butterfield, D. Allan

    2017-01-01

    Abstract Aims: Microglial cells are brain-resident macrophages engaged in surveillance and maintained in a constant state of relative inactivity. However, their involvement in autoimmune diseases indicates that in pathological conditions microglia gain an inflammatory phenotype. The mechanisms underlying this change in the microglial phenotype are still unclear. Since metabolism is an important modulator of immune cell function, we focused our attention on glutamine synthetase (GS), a modulator of the response to lipopolysaccharide (LPS) activation in other cell types, which is expressed by microglia. Results: GS inhibition enhances release of inflammatory mediators of LPS-activated microglia in vitro, leading to perturbation of the redox balance and decreased viability of cocultured neurons. GS inhibition also decreases insulin-mediated glucose uptake in microglia. In vivo, microglia-specific GS ablation enhances expression of inflammatory markers upon LPS treatment. In the spinal cords from experimental autoimmune encephalomyelitis (EAE), GS expression levels and glutamine/glutamate ratios are reduced. Innovation: Recently, metabolism has been highlighted as mediator of immune cell function through the discovery of mechanisms that (behind these metabolic changes) modulate the inflammatory response. The present study shows for the first time a metabolic mechanism mediating microglial response to a proinflammatory stimulus, pointing to GS activity as a master modulator of immune cell function and thus unraveling a potential therapeutic target. Conclusions: Our study highlights a new role of GS in modulating immune response in microglia, providing insights into the pathogenic mechanisms associated with inflammation and new strategies of therapeutic intervention. Antioxid. Redox Signal. 26, 351–363. PMID:27758118

  11. The responses of immune cells to iron oxide nanoparticles.

    Science.gov (United States)

    Xu, Yaolin; Sherwood, Jennifer A; Lackey, Kimberly H; Qin, Ying; Bao, Yuping

    2016-04-01

    Immune cells play an important role in recognizing and removing foreign objects, such as nanoparticles. Among various parameters, surface coatings of nanoparticles are the first contact with biological system, which critically affect nanoparticle interactions. Here, surface coating effects on nanoparticle cellular uptake, toxicity and ability to trigger immune response were evaluated on a human monocyte cell line using iron oxide nanoparticles. The cells were treated with nanoparticles of three types of coatings (negatively charged polyacrylic acid, positively charged polyethylenimine and neutral polyethylene glycol). The cells were treated at various nanoparticle concentrations (5, 10, 20, 30, 50 μg ml(-1) or 2, 4, 8, 12, 20 μg cm(-2)) with 6 h incubation or treated at a nanoparticle concentration of 50 μg ml(-1) (20 μg cm(-2)) at different incubation times (6, 12, 24, 48 or 72 h). Cell viability over 80% was observed for all nanoparticle treatment experiments, regardless of surface coatings, nanoparticle concentrations and incubation times. The much lower cell viability for cells treated with free ligands (e.g. ~10% for polyethylenimine) suggested that the surface coatings were tightly attached to the nanoparticle surfaces. The immune responses of cells to nanoparticles were evaluated by quantifying the expression of toll-like receptor 2 and tumor necrosis factor-α. The expression of tumor necrosis factor-α and toll-like receptor 2 were not significant in any case of the surface coatings, nanoparticle concentrations and incubation times. These results provide useful information to select nanoparticle surface coatings for biological and biomedical applications.

  12. Dendritic cell-derived IL-15 controls the induction of CD8 T cell immune responses.

    Science.gov (United States)

    Rückert, René; Brandt, Katja; Bulanova, Elena; Mirghomizadeh, Farhad; Paus, Ralf; Bulfone-Paus, Silvia

    2003-12-01

    The development and the differentiation of CD8(+) T cells are dependent on IL-15. Here, we have studied the source and mechanism of how IL-15 modulates CD8(+) T cell-mediated Th1 immune responses by employing two delayed-type hypersensitivity (DTH) models. IL-15-deficient (IL-15(-/-)) mice or mice treated with soluble IL-15Ralpha as an IL-15 antagonist showed significantly reduced CD8(+) T cell-dependent DTH responses, while activation of CD4(+) T cell and B cell functions remained unaffected. Injection of antigen-labeled dendritic cells (DC) from IL-15(+/+), IL-15(-/-) or IL-15Ralpha(-/-) mice revealed that DC-derived IL-15 is an absolute requirement for the initiation of DTH response. The re-establishment of the interaction of IL-15 with the IL-15Ralpha by incubating IL-15(-/-) DC with IL-15 completely restored the capacity to prime T cells for DTH induction in vivo. Moreover, IL-15 also enhanced secretion of pro-inflammatory cytokines by DC and triggered in vitro CD8(+) T cell proliferation and IL-2 release. Taken together, the data suggest that an autocrine IL-15/IL-15Ralpha signaling loop in DC is essential for inducing CD8(+)-dependent Th1 immune responses in mice. Therefore, targeted manipulation of this loop promises to be an effective, novel strategy for therapeutic modulation of clinically relevant DTH reactions.

  13. 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.

  14. 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. PMID:28174578

  15. T-cell responses associated with neonatal alloimmune thrombocytopenia: isolation of HPA-1a-specific, HLA-DRB3*0101-restricted CD4+ T cells.

    Science.gov (United States)

    Ahlen, Maria Therese; Husebekk, Anne; Killie, Mette Kjaer; Skogen, Bjørn; Stuge, Tor B

    2009-04-16

    T-cell responses have been implicated in the development of HPA-1a-induced neonatal alloimmune thrombocytopenia (NAIT). However, HPA-1a-specific T cells have neither been isolated nor characterized. Here, we aimed to determine whether HPA-1a-specific T cells could be isolated from HPA-1a-immunized women. In the present study, peripheral blood mononuclear cells (PBMCs) from an HPA-1a-alloimmunized woman were cultured for weeks in the presence of HPA-1a peptide, labeled with CFSE, and assayed for antigen-specific proliferation. Individual proliferating cells were isolated by fluorescence-activated cell sorting and expanded in culture. Antigen specificity and HLA restriction were determined by cytokine secretion (enzyme-linked immunospot [ELISPOT]) and proliferation assays. Several CD3(+)CD4(+) T-cell clones were isolated that proliferated and secreted cytokines in response to HPA-1a peptide. Two of these clones have been established in long-term culture in our laboratory. Both of these recognize synthetic as well as naturally processed HPA-1a antigen, and the recognition is restricted by the MHC molecule HLA-DRB3*0101 that is strongly associated with NAIT. These HPA-1a-specific T-cell clones represent unambiguous evidence for the association of T-cell responses with NAIT, and they will serve as unique tools to elucidate the cellular immune response that may result in NAIT.

  16. The California Health Policy Research Program - supporting policy making through evidence and responsive research.

    Science.gov (United States)

    Roby, Dylan H; Jacobs, Ken; Kertzner, Alex E; Kominski, Gerald F

    2014-08-01

    This article explores the creation, design, and execution of a university-based collaboration to provide responsive research and evidence to a group of diverse health care, labor, and consumer stakeholders through convening a funded series of deliberative meetings, research briefs, peer-reviewed journal articles, ad hoc data analyses, and policy analyses. Funded by the California Endowment, the California Health Policy Research Program was created by researchers at the University of California, Berkeley Center for Labor Research and Education, and the UCLA Center for Health Policy Research. The collaboration not only allowed new research and analyses to be used by stakeholders and policy makers in decision making but also allowed university researchers to receive input on the important health policy issues of the day. The guidance of stakeholders in the research and policy analysis process was vital in driving meaningful results during an important time in health policy making in California. The manuscript discusses lessons learned in building relationships with stakeholders; meeting research and analytic needs; engaging stakeholders and policy makers; building capacity for quick-turnaround data collection and analysis, dissemination and publication; and maintaining the collaboration.

  17. Control of the C. albicans cell wall damage response by transcriptional regulator Cas5.

    Directory of Open Access Journals (Sweden)

    Vincent M Bruno

    2006-03-01

    Full Text Available The fungal cell wall is vital for growth, development, and interaction of cells with their environment. The response to cell wall damage is well understood from studies in the budding yeast Saccharomyces cerevisiae, where numerous cell wall integrity (CWI genes are activated by transcription factor ScRlm1. Prior evidence suggests the hypothesis that both response and regulation may be conserved in the major fungal pathogen Candida albicans. We have tested this hypothesis by using a new C. albicans genetic resource: we have screened mutants defective in putative transcription factor genes for sensitivity to the cell wall biosynthesis inhibitor caspofungin. We find that the zinc finger protein CaCas5, which lacks a unique ortholog in S. cerevisiae, governs expression of many CWI genes. CaRlm1 has a modest role in this response. The transcriptional coactivator CaAda2 is also required for expression of many CaCas5-dependent genes, as expected if CaCas5 recruits CaAda2 to activate target gene transcription. Many caspofungin-induced C. albicans genes specify endoplasmic reticulum and secretion functions. Such genes are not induced in S. cerevisiae, but promote its growth in caspofungin. We have used a new resource to identify a key C. albicans transcriptional regulator of CWI genes and antifungal sensitivity. Our gene expression findings indicate that both divergent and conserved response genes may have significant functional roles. Our strategy may be broadly useful for identification of pathogen-specific regulatory pathways and critical response genes.

  18. T-cell response to p53 tumor-associated antigen in patients with colorectal carcinoma.

    Science.gov (United States)

    Bueter, Marco; Gasser, Martin; Schramm, Nicolai; Lebedeva, Tatiana; Tocco, Georges; Gerstlauer, Christiane; Grimm, Martin; Nichiporuk, Ekaterina; Thalheimer, Andreas; Thiede, Arnulf; Meyer, Detlef; Benichou, Gilles; Waaga-Gasser, Ana Maria

    2006-02-01

    Despite the radical surgical resection performed in patients with colorectal carcinoma, there is a high rate of tumor recurrence. Over an observation period of 3 years, 18% of the patients in our collective suffered a tumor relapse with local or distinct metastases after initial R0-resection. Some evidence suggests that this may be due to suppression of anti-tumor responses, a phenomenon that might be attributed to regulatory T cells. The aim of our study was to investigate the tumor-specific immune response depending on the UICC stage of patients with colorectal cancer. The cellular immune responses against defined antigens that are overexpressed in most of the patients with colorectal cancer were characterized. For this purpose, the tumor suppressor gene, p53, was chosen as the tumor-associated antigen that exhibits mutations and overexpression in up to 60% of colorectal carcinoma. We observed that p53 induced both IFN-gamma and IL-10 secretion. The predominance of IL-10 production indicated that regulatory T cells directly participate in modulating the anti-tumor immune response. IL-10 levels in the blood as well as the expression of regulatory T-cell specific genes at the tumor site correlate with the UICC stage of the disease. These results may provide an explanation for the poor prognosis and increased recurrence rate in patients with advanced carcinoma.

  19. Dissecting the Transcriptional Response to Elicitors in Vitis vinifera Cells

    Science.gov (United States)

    Belchí-Navarro, Sarai; Bru, Roque; Martínez-Zapater, José M.; Lijavetzky, Diego; Pedreño, María A.

    2014-01-01

    The high effectiveness of cyclic oligosaccharides like cyclodextrins in the production of trans-resveratrol in Vitis vinifera cell cultures is enhanced in the presence of methyl jasmonate. In order to dissect the basis of the interactions among the elicitation responses triggered by these two compounds, a transcriptional analysis of grapevine cell cultures treated with cyclodextrins and methyl jasmonate separately or in combination was carried out. The results showed that the activation of genes encoding enzymes from phenylpropanoid and stilbene biosynthesis induced by cyclodextrins alone was partially enhanced in the presence of methyl jasmonate, which correlated with their effects on trans-resveratrol production. In addition, protein translation and cell cycle regulation were more highly repressed in cells treated with cyclodextrins than in those treated with methyl jasmonate, and this response was enhanced in the combined treatment. Ethylene signalling was activated by all treatments, while jasmonate signalling and salicylic acid conjugation were activated only in the presence of methyl jasmonate and cyclodextrins, respectively. Moreover, the combined treatment resulted in a crosstalk between the signalling cascades activated by cyclodextrins and methyl jasmonate, which, in turn, provoked the activation of additional regulatory pathways involving the up-regulation of MYB15, NAC and WRKY transcription factors, protein kinases and calcium signal transducers. All these results suggest that both elicitors cause an activation of the secondary metabolism in detriment of basic cell processes like the primary metabolism or cell division. Crosstalk between cyclodextrins and methyl jasmonate-induced signalling provokes an intensification of these responses resulting in a greater trans-resveratrol production. PMID:25314001

  20. 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.

  1. Chemical engineering of mesenchymal stem cells to induce a cell rolling response.

    Science.gov (United States)

    Sarkar, Debanjan; Vemula, Praveen Kumar; Teo, Grace S L; Spelke, Dawn; Karnik, Rohit; Wee, Le Y; Karp, Jeffrey M

    2008-11-19

    Covalently conjugated sialyl Lewis X (SLeX) on the mesenchymal stem cell (MSC) surface through a biotin-streptavidin bridge imparts leukocyte-like rolling characteristics without altering the cell phenotype and the multilineage differentiation potential. We demonstrate that the conjugation of SLeX on the MSC surface is stable, versatile, and induces a robust rolling response on P-selectin coated substrates. These results indicate the potential to increase the targeting efficiency of any cell type to specific tissue.

  2. DNA Damage Response in Hematopoietic Stem Cell Ageing

    Institute of Scientific and Technical Information of China (English)

    Tangliang Li; Zhong-Wei Zhou; Zhenyu Ju; Zhao-Qi Wang

    2016-01-01

    Maintenance of tissue-specific stem cells is vital for organ homeostasis and organismal longevity. Hematopoietic stem cells (HSCs) are the most primitive cell type in the hematopoietic system. They divide asymmetrically and give rise to daughter cells with HSC identity (self-renewal) and progenitor progenies (differentiation), which further proliferate and differentiate into full hematopoietic lineages. Mammalian ageing process is accompanied with abnormalities in the HSC self-renewal and differentiation. Transcriptional changes and epigenetic modulations have been implicated as the key regulators in HSC ageing process. The DNA damage response (DDR) in the cells involves an orchestrated signaling pathway, consisting of cell cycle regulation, cell death and senescence, transcriptional regulation, as well as chromatin remodeling. Recent studies employ-ing DNA repair-deficient mouse models indicate that DDR could intrinsically and extrinsically reg-ulate HSC maintenance and play important roles in tissue homeostasis of the hematopoietic system. In this review, we summarize the current understanding of how the DDR determines the HSC fates and finally contributes to organismal ageing.

  3. The acquisition of cytokine responsiveness by murine B cells

    DEFF Research Database (Denmark)

    Poudrier, J; Owens, T

    1994-01-01

    chains and mRNA to levels comparable to those seen in activated T cells. Anti-mu-stimulated B cells responded to IL-2 by incorporation of [3H]thymidine and high rate immunoglobulin (Ig) secretion. Both IL-5 (at optimal concentration) and suboptimal lipopolysaccharide (LPS; 20 ng/ml) induced surface...... expression of IL-2R alpha. The level of expression induced by IL-5 was equivalent to that on anti-Ig-activated B cells. Neither stimulus induced detectable expression of IL-2R beta, and neither induced B cells to respond to IL-2. IL-2R alpha expression was strongly enhanced, and low levels of IL-2R beta...... staining and mRNA were induced by the combination of LPS plus IL-5. LPS+IL-5-treated B cells responded to IL-2 by Ig secretion. This indicates that B cells regulate their responsiveness to IL-2 similarly to T cells, via the combined level of expression of IL-2R beta and IL-2R alpha. The synergy between IL...

  4. DNA Damage Response in Hematopoietic Stem Cell Ageing.

    Science.gov (United States)

    Li, Tangliang; Zhou, Zhong-Wei; Ju, Zhenyu; Wang, Zhao-Qi

    2016-06-01

    Maintenance of tissue-specific stem cells is vital for organ homeostasis and organismal longevity. Hematopoietic stem cells (HSCs) are the most primitive cell type in the hematopoietic system. They divide asymmetrically and give rise to daughter cells with HSC identity (self-renewal) and progenitor progenies (differentiation), which further proliferate and differentiate into full hematopoietic lineages. Mammalian ageing process is accompanied with abnormalities in the HSC self-renewal and differentiation. Transcriptional changes and epigenetic modulations have been implicated as the key regulators in HSC ageing process. The DNA damage response (DDR) in the cells involves an orchestrated signaling pathway, consisting of cell cycle regulation, cell death and senescence, transcriptional regulation, as well as chromatin remodeling. Recent studies employing DNA repair-deficient mouse models indicate that DDR could intrinsically and extrinsically regulate HSC maintenance and play important roles in tissue homeostasis of the hematopoietic system. In this review, we summarize the current understanding of how the DDR determines the HSC fates and finally contributes to organismal ageing.

  5. DNA Damage Response in Hematopoietic Stem Cell Ageing

    Directory of Open Access Journals (Sweden)

    Tangliang Li

    2016-06-01

    Full Text Available Maintenance of tissue-specific stem cells is vital for organ homeostasis and organismal longevity. Hematopoietic stem cells (HSCs are the most primitive cell type in the hematopoietic system. They divide asymmetrically and give rise to daughter cells with HSC identity (self-renewal and progenitor progenies (differentiation, which further proliferate and differentiate into full hematopoietic lineages. Mammalian ageing process is accompanied with abnormalities in the HSC self-renewal and differentiation. Transcriptional changes and epigenetic modulations have been implicated as the key regulators in HSC ageing process. The DNA damage response (DDR in the cells involves an orchestrated signaling pathway, consisting of cell cycle regulation, cell death and senescence, transcriptional regulation, as well as chromatin remodeling. Recent studies employing DNA repair-deficient mouse models indicate that DDR could intrinsically and extrinsically regulate HSC maintenance and play important roles in tissue homeostasis of the hematopoietic system. In this review, we summarize the current understanding of how the DDR determines the HSC fates and finally contributes to organismal ageing.

  6. Hematopoietic Stem/Progenitor Cells Express Several Functional Sex Hormone Receptors—Novel Evidence for a Potential Developmental Link Between Hematopoiesis and Primordial Germ Cells

    Science.gov (United States)

    Mierzejewska, Katarzyna; Borkowska, Sylwia; Suszynska, Ewa; Suszynska, Malwina; Poniewierska-Baran, Agata; Maj, Magda; Pedziwiatr, Daniel; Adamiak, Mateusz; Abdel-Latif, Ahmed; Kakar, Sham S.; Ratajczak, Janina; Kucia, Magda

    2015-01-01

    Evidence has accumulated that hematopoietic stem progenitor cells (HSPCs) share several markers with the germline, a connection supported by reports that prolactin, androgens, and estrogens stimulate hematopoiesis. To address this issue more directly, we tested the expression of receptors for pituitary-derived hormones, such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH), on purified murine bone marrow (BM) cells enriched for HSPCs and tested the functionality of these receptors in ex vivo signal transduction studies and in vitro clonogenic assays. We also tested whether administration of pituitary- and gonad-derived sex hormones (SexHs) increases incorporation of bromodeoxyuridine (BrdU) into HSPCs and expansion of hematopoietic clonogenic progenitors in mice and promotes recovery of blood counts in sublethally irradiated animals. We report for the first time that HSPCs express functional FSH and LH receptors and that both proliferate in vivo and in vitro in response to stimulation by pituitary SexHs. Furthermore, based on our observations that at least some of CD45− very small embryonic-like stem cells (VSELs) may become specified into CD45+ HSPCs, we also evaluated the expression of pituitary and gonadal SexHs receptors on these cells and tested whether these quiescent cells may expand in vivo in response to SexHs administration. We found that VSELs express SexHs receptors and respond in vivo to SexHs stimulation, as evidenced by BrdU accumulation. Since at least some VSELs share several markers characteristic of migrating primordial germ cells and can be specified into HSPCs, this observation sheds new light on the BM stem cell hierarchy. PMID:25607657

  7. Adenoviral transduction of mesenchymal stem cells: in vitro responses and in vivo immune responses after cell transplantation.

    Directory of Open Access Journals (Sweden)

    Oliver Treacy

    Full Text Available Adult mesenchymal stem cells (MSCs are non-hematopoietic cells with multi-lineage potential which makes them attractive targets for regenerative medicine applications. However, to date, therapeutic success of MSC-therapy is limited and the genetic modification of MSCs using viral vectors is one option to improve their therapeutic potential. Ex-vivo genetic modification of MSCs using recombinant adenovirus (Ad could be promising to reduce undesired immune responses as Ad will be removed before cell/tissue transplantation. In this regard, we investigated whether Ad-modification of MSCs alters their immunological properties in vitro and in vivo. We found that Ad-transduction of MSCs does not lead to up-regulation of major histocompatibility complex class I and II and co-stimulatory molecules CD80 and CD86. Moreover, Ad-transduction caused no significant changes in terms of pro-inflammatory cytokine expression, chemokine and chemokine receptor and Toll-like receptor expression. In addition, Ad-modification of MSCs had no affect on their ability to suppress T cell proliferation in vitro. In vivo injection of Ad-transduced MSCs did not change the frequency of various immune cell populations (antigen presenting cells, T helper and cytotoxic T cells, natural killer and natural killer T cells neither in the blood nor in tissues. Our results indicate that Ad-modification has no major influence on the immunological properties of MSCs and therefore can be considered as a suitable gene vector for therapeutic applications of MSCs.

  8. Effects of the Cell Cycle Inhibitor Olomoucine on Inflammatory Response and Neuronal Cell Death after Spinal Cord Injury in Rats

    Institute of Scientific and Technical Information of China (English)

    TIAN Dai-shi; XIE Min-jie; YU Zhi-yuan; ZHANG Qiang; WANG Yi-hui; CHEN Bin; CHEN Chen; WANG Wei

    2007-01-01

    Objective:The influence of olomoucine on microglial proliferation with associated inflammatory response after spinal cord injury has been determined.Methods:Microglial proliferation and neuronal apoptosis were observed by immunofluorescence.Level of the proinflammatory cytokine interleukin-1β (IL-1β) expression in the injured cord was determined by Western blot analysis.Results:the cell cycle inhibitor olomoucine,administered at 1 h post injury,significantly suppressed microglial proliferation and produced a remarkable reduction of tissue edema formation.In the olomoucine-treated group,a significant reduction of activated and/or proliferated microglial induced IL-1β expression was observed 24 h after SCI.Moreover,olomoucine evidently attenuated the number of apoptotic neurons after SCI.Conclusion:Our findings suggest that modulation of microglial proliferation with associated proinflammatory cytokine expression may be a mechanism of cell cycle inhibition-mediated neuroprotections in the CNS trauma.

  9. Evidence for land plant cell wall biosynthetic mechanisms in charophyte green algae

    DEFF Research Database (Denmark)

    Mikkelsen, Maria Dalgaard; Harholt, Jesper; Ulvskov, Peter

    2014-01-01

    characterized in land plants. In addition, gene cloning was employed in two cases to answer important evolutionary questions. KEY RESULTS: Genetic evidence was obtained indicating that many of the most important core cell wall polysaccharides have their evolutionary origins in the CGA, including cellulose...... to colonize land. These cell walls provide support and protection, are a source of signalling molecules, and provide developmental cues for cell differentiation and elongation. The cell wall of land plants is a highly complex fibre composite, characterized by cellulose cross-linked by non......-cellulosic polysaccharides, such as xyloglucan, embedded in a matrix of pectic polysaccharides. How the land plant cell wall evolved is currently unknown: early-divergent chlorophyte and prasinophyte algae genomes contain a low number of glycosyl transferases (GTs), while land plants contain hundreds. The number of GTs...

  10. Macroautophagy and Cell Responses Related to Mitochondrial Dysfunction, Lipid Metabolism and Unconventional Secretion of Proteins

    Science.gov (United States)

    Demine, Stéphane; Michel, Sébastien; Vannuvel, Kayleen; Wanet, Anaïs; Renard, Patricia; Arnould, Thierry

    2012-01-01

    Macroautophagy has important physiological roles and its cytoprotective or detrimental function is compromised in various diseases such as many cancers and metabolic diseases. However, the importance of autophagy for cell responses has also been demonstrated in many other physiological and pathological situations. In this review, we discuss some of the recently discovered mechanisms involved in specific and unspecific autophagy related to mitochondrial dysfunction and organelle degradation, lipid metabolism and lipophagy as well as recent findings and evidence that link autophagy to unconventional protein secretion. PMID:24710422

  11. Macroautophagy and Cell Responses Related to Mitochondrial Dysfunction, Lipid Metabolism and Unconventional Secretion of Proteins

    Directory of Open Access Journals (Sweden)

    Thierry Arnould

    2012-06-01

    Full Text Available Macroautophagy has important physiological roles and its cytoprotective or detrimental function is compromised in various diseases such as many cancers and metabolic diseases. However, the importance of autophagy for cell responses has also been demonstrated in many other physiological and pathological situations. In this review, we discuss some of the recently discovered mechanisms involved in specific and unspecific autophagy related to mitochondrial dysfunction and organelle degradation, lipid metabolism and lipophagy as well as recent findings and evidence that link autophagy to unconventional protein secretion.

  12. Responses of Squalius cephalus intestinal mucous cells to Pomphorhynchus laevis.

    Science.gov (United States)

    Bosi, Giampaolo; Sayyaf Dezfuli, Bahram

    2015-04-01

    Intestinal mucous cell numbers and their glycoconjugate composition were investigated by histochemical methods in uninfected chub, Squalius cephalus, and in conspecifics naturally parasitised with the acanthocephalan Pomphorhynchus laevis. A sub-population of 42 chub from the River Tiber (Perugia, Italy) were sampled and screened for ecto and endoparasites. No parasites were found in gills and in other visceral organs of chub and P. laevis appeared to be the only enteric worm encountered. In all infected chub (twenty-eight out of 42) this acanthocephalan was encountered mainly in the mid-gut. In situ, an excessive yellowish mucus or catarrh was observed around each acanthocephalan. Hyperplasia and hypertrophy of the mucous cells were only evident near the site of P. laevis attachment where the total number of mucous cells and the number of those containing acidic, particularly non-sulphated mucins, or mixed glycoconjugates were significantly higher. In intestinal regions of infected fish far away from the point of parasite attachment, there were no statistical differences in the density of mucous cells in comparison to uninfected fish. Interestingly, in parasitised chub, the length of intestinal folds was significantly larger close to the sites at which P. laevis attach when compared to the length of the intestinal folds located further away from the acanthocephalans and/or in uninfected intestines. The effect of P. laevis on intestinal mucous cells of S. cephalus was compared to other parasite-host systems and the role of enhanced mucus production in parasitized intestines was discussed.

  13. 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.

  14. Cell wall modification in grapevine cells in response to UV stress investigated by atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lesniewska, E.; Adrian, M.; Klinguer, A.; Pugin, A

    2004-08-15

    Despite cell wall reinforcement being a well-known defence mechanism of plants, it remains poorly characterized from a physical point of view. The objective of this work was to further describe this mechanism. Vitis vinifera cv Gamay cells were treated with UV-light (254 nm), a well-known elicitor of defence mechanisms in grapevines, and physical cell wall modifications were observed using the atomic force microscopy (AFM) under native conditions. The grapevine cell suspensions were continuously observed in their culture medium from 30 min to 24 h after elicitation. In the beginning, cellulose fibrils covered by a matrix surrounded the control and treated cells. After 3 h, the elicited cells displayed sprouted expansions around the cell wall that correspond to pectin chains. These expansions were not observed on untreated grapevine cells. The AFM tip was used to determine the average surface elastic modulus of cell wall that account for cell wall mechanical properties. The elasticity is diminished in UV-treated cells. In a comparative study, grapevine cells showed the same decrease in cell wall elasticity when treated with a fungal biotic elicitor of defence response. These results demonstrate cell wall strengthening by UV stress.

  15. Bioreporters: gfp versus lux revisited and single-cell response.

    Science.gov (United States)

    Kohlmeier, Stefanie; Mancuso, Matthew; Tecon, Robin; Harms, Hauke; van der Meer, Jan Roelof; Wells, Mona

    2007-03-15

    Genetically engineered organisms expressing spectroscopically active reporter molecules in response to chemical effectors display great potential as living transducers in sensing applications. Green fluorescent protein (gfp gene) bioreporters have distinct advantages over luminescent couterparts (lux gene), including applicability at the single-cell level, but are typically less sensitive. Here we describe a gfp-bearing bioreporter that is sensitive to naphthalene (a poorly water soluble pollutant behaving like a large class of hydrophobic compounds), is suitable for use in chemical assays and bioavailability studies, and has detection limits comparable to lux-bearing bioreporters for higher efficiency detection strategies. Simultaneously, we find that the exploitation of population response data from single-cell analysis is not an algorithmic conduit to enhanced signal detection and hence lower effector detection limits, as normally assumed. The assay reported functions to equal effect with or without biocide.

  16. Oral epithelial cell responses to multispecies microbial biofilms.

    Science.gov (United States)

    Peyyala, R; Kirakodu, S S; Novak, K F; Ebersole, J L

    2013-03-01

    This report describes the use of a novel model of multispecies biofilms to stimulate profiles of cytokines/chemokines from oral epithelial cells that contribute to local inflammation in the periodontium. Streptococcus gordonii (Sg)/S. oralis (So)/S. sanguinis (Ss) and Sg/Fusobacterium nucleatum (Fn)/Porphyromonas gingivalis (Pg) biofilms elicited significantly elevated levels of IL-1α and showed synergistic stimulatory activity compared with an additive effect of the 3 individual bacteria. Only the Sg/Actinomyces naeslundii (An)/Fn multispecies biofilms elicited IL-6 levels above those of control. IL-8 was a primary response to the Sg/An/Fn biofilms, albeit the level was not enhanced compared with a predicted composite level from the monospecies challenges. These results represent some of the first data documenting alterations in profiles of oral epithelial cell responses to multispecies biofilms.

  17. Modeling of Cancer Stem Cell State Transitions Predicts Therapeutic Response.

    Directory of Open Access Journals (Sweden)

    Mary E Sehl

    Full Text Available Cancer stem cells (CSCs possess capacity to both self-renew and generate all cells within a tumor, and are thought to drive tumor recurrence. Targeting the stem cell niche to eradicate CSCs represents an important area of therapeutic development. The complex nature of many interacting elements of the stem cell niche, including both intracellular signals and microenvironmental growth factors and cytokines, creates a challenge in choosing which elements to target, alone or in combination. Stochastic stimulation techniques allow for the careful study of complex systems in biology and medicine and are ideal for the investigation of strategies aimed at CSC eradication. We present a mathematical model of the breast cancer stem cell (BCSC niche to predict population dynamics during carcinogenesis and in response to treatment. Using data from cell line and mouse xenograft experiments, we estimate rates of interconversion between mesenchymal and epithelial states in BCSCs and find that EMT/MET transitions occur frequently. We examine bulk tumor growth dynamics in response to alterations in the rate of symmetric self-renewal of BCSCs and find that small changes in BCSC behavior can give rise to the Gompertzian growth pattern observed in breast tumors. Finally, we examine stochastic reaction kinetic simulations in which elements of the breast cancer stem cell niche are inhibited individually and in combination. We find that slowing self-renewal and disrupting the positive feedback loop between IL-6, Stat3 activation, and NF-κB signaling by simultaneous inhibition of IL-6 and HER2 is the most effective combination to eliminate both mesenchymal and epithelial populations of BCSCs. Predictions from our model and simulations show excellent agreement with experimental data showing the efficacy of combined HER2 and Il-6 blockade in reducing BCSC populations. Our findings will be directly examined in a planned clinical trial of combined HER2 and IL-6 targeted

  18. Thyroid hormone responsiveness in N-Tera-2 cells.

    Science.gov (United States)

    Chan, S; McCabe, C J; Visser, T J; Franklyn, J A; Kilby, M D

    2003-07-01

    N-TERA-2 cl/D1 (NT2) cells, a human embryonal cell line with characteristics of central nervous system precursor cells, were utilised to study thyroid hormone action during early neuronal growth and differentiation. Undifferentiated NT2 cells expressed mRNAs encoding thyroid hormone receptors (TRs) alpha1, alpha2 and beta1, iodothyronine deiodinases types 2 (D2) and 3 (D3) (which act as the pre-receptor regulators), and the thyroid hormone-responsive genes myelin basic protein (MBP) and neuroendocrine specific protein A (NSP-A). When terminally differentiated into post-mitotic neurons (hNT), TRalpha1 and TRbeta1 mRNA expression was decreased by 74% (P=0.05) and 95% (P<0.0001) respectively, while NSP-A mRNA increased 7-fold (P<0.05). However, mRNAs encoding TRalpha2, D2, D3 and MBP did not alter significantly upon neuronal differentiation and neither did activities of D2 and D3. With increasing 3,5,3'-triiodothyronine (T(3)) concentrations, TRbeta1 mRNA expression in cultured NT2 cells increased 2-fold at 10 nM T(3) and 1.3-fold at 100 nM T(3) (P<0.05) compared with that in T(3)-free media but no change was seen with T(3) treatment of hNT cells. D3 mRNA expression in NT2 cells also increased 3-fold at 10 nM T(3) (P=0.01) and 2.4-fold at 100 nM T(3) (P<0.05) compared with control, but there was no change in D3 enzyme activity. In contrast there was a 20% reduction in D3 mRNA expression in hNT cells at 10 nM T(3) (P<0.05) compared with control, with accompanying reductions in D3 activity with increasing T(3) concentrations (P<0.05). There was no significant change in the expression of the TRalpha isoforms, D2, MBP and NSP-A with increasing T(3) concentrations in either NT2 or hNT cells. Undifferentiated NT2 and differentiated hNT cells show differing patterns of T(3)-responsiveness, suggesting that there are different regulatory factors operating within these cell types.

  19. MYSM1-dependent checkpoints in B cell lineage differentiation and B cell-mediated immune response.

    Science.gov (United States)

    Förster, Michael; Farrington, Kyo; Petrov, Jessica C; Belle, Jad I; Mindt, Barbara C; Witalis, Mariko; Duerr, Claudia U; Fritz, Jörg H; Nijnik, Anastasia

    2017-03-01

    MYSM1 is a chromatin-binding histone deubiquitinase. MYSM1 mutations in humans result in lymphopenia whereas loss of Mysm1 in mice causes severe hematopoietic abnormalities, including an early arrest in B cell development. However, it remains unknown whether MYSM1 is required at later checkpoints in B cell development or for B cell-mediated immune responses. We analyzed conditional mouse models Mysm1(fl/fl)Tg.mb1-cre, Mysm1(fl/fl)Tg.CD19-cre, and Mysm1(fl/fl)Tg.CD21-cre with inactivation of Mysm1 at prepro-B, pre-B, and follicular B cell stages of development. We show that loss of Mysm1 at the prepro-B cell stage in Mysm1(fl/fl)Tg.mb1-cre mice results in impaired B cell differentiation, with an ∼2-fold reduction in B cell numbers in the lymphoid organs. Mysm1(fl/fl)Tg.mb1-cre B cells also showed increased expression of activation markers and impaired survival and proliferation. In contrast, Mysm1 was largely dispensable from the pre-B cell stage onward, with Mysm1(fl/fl)Tg.CD19-cre and Mysm1(fl/fl)Tg.CD21-cre mice showing no alterations in B cell numbers and largely normal responses to stimulation. MYSM1, therefore, has an essential role in B cell lineage specification but is dispensable at later stages of development. Importantly, MYSM1 activity at the prepro-B cell stage of development is important for the normal programming of B cell responses to stimulation once they complete their maturation process.

  20. Glioblastoma stem cells: radiobiological response to ionising radiations of different qualities.

    Science.gov (United States)

    Pecchia, I; Dini, V; Ricci-Vitiani, L; Biffoni, M; Balduzzi, M; Fratini, E; Belli, M; Campa, A; Esposito, G; Cirrone, G; Romano, F; Stancampiano, C; Pelacchi, F; Pallini, R; Tabocchini, M A

    2015-09-01

    Glioblastoma multiforme (GBM) is the most common and malignant primary brain tumour, with very poor prognosis. The high recurrence rate and failure of conventional treatments are expected to be related to the presence of radio-resistant cancer stem cells (CSCs) inside the tumour mass. CSCs can both self-renew and differentiate into the heterogeneous lineages of cancer cells. Recent evidence showed a higher effectiveness of C-ions and protons in inactivating CSCs, suggesting a potential advantage of Hadrontherapy compared with conventional radiotherapy for GBM treatment. To investigate the mechanisms involved in the molecular and cellular responses of CSCs to ionising radiations, two GBM stem cell (GSC) lines, named lines 1 and 83, which were derived from patients with different clinical outcomes and having different metabolic profiles (as shown by NMR spectroscopy), were irradiated with (137)Cs photons and with protons or C-ions of 62 MeV u(-1) in the dose range of 5-40 Gy. The biological effects investigated were: cell death, cell cycle progression, and DNA damage induction and repair. Preliminary results show a different response to ionising radiation between the two GSC lines for the different end points investigated. Further experiments are in progress to consolidate the data and to get more insights on the influence of radiation quality.

  1. The fractional viscoelastic response of human breast tissue cells

    Science.gov (United States)

    Carmichael, B.; Babahosseini, H.; Mahmoodi, S. N.; Agah, M.

    2015-07-01

    The mechanical response of a living cell is notoriously complicated. The complex, heterogeneous characteristics of cellular structure introduce difficulties that simple linear models of viscoelasticity cannot overcome, particularly at deep indentation depths. Herein, a nano-scale stress-relaxation analysis performed with an atomic force microscope reveals that isolated human breast cells do not exhibit simple exponential relaxation capable of being modeled by the standard linear solid (SLS) model. Therefore, this work proposes the application of the fractional Zener (FZ) model of viscoelasticity to extract mechanical parameters from the entire relaxation response, improving upon existing physical techniques to probe isolated cells. The FZ model introduces a new parameter that describes the fractional time-derivative dependence of the response. The results show an exceptional increase in conformance to the experimental data compared to that predicted by the SLS model, and the order of the fractional derivative (α) is remarkably homogeneous across the populations, with a median value of 0.48 ± 0.06 for the malignant population and 0.51 ± 0.07 for the benign. The cells’ responses exhibit power-law behavior and complexity not associated with simple relaxation (SLS, α = 1) that supports the application of a fractional model. The distributions of some of the FZ parameters also preserve the distinction between the malignant and benign sample populations seen from the linear model and previous results while including the contribution of fast-relaxation behavior. The resulting viscosity, measured by a composite relaxation time, exhibits considerably less dispersion due to residual error than the distribution generated by the linear model and therefore serves as a more powerful marker for cell differentiation.

  2. Role of cell-to-cell variability in activating a positive feedback antiviral response in human dendritic cells.

    Directory of Open Access Journals (Sweden)

    Jianzhong Hu

    Full Text Available In the first few hours following Newcastle disease viral infection of human monocyte-derived dendritic cells, the induction of IFNB1 is extremely low and the secreted type I interferon response is below the limits of ELISA assay. However, many interferon-induced genes are activated at this time, for example DDX58 (RIGI, which in response to viral RNA induces IFNB1. We investigated whether the early induction of IFNBI in only a small percentage of infected cells leads to low level IFN secretion that then induces IFN-responsive genes in all cells. We developed an agent-based mathematical model to explore the IFNBI and DDX58 temporal dynamics. Simulations showed that a small number of early responder cells provide a mechanism for efficient and controlled activation of the DDX58-IFNBI positive feedback loop. The model predicted distributions of single cell responses that were confirmed by single cell mRNA measurements. The results suggest that large cell-to-cell variation plays an important role in the early innate immune response, and that the variability is essential for the efficient activation of the IFNB1 based feedback loop.

  3. 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.

  4. 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.

  5. Exercise-induced B cell mobilisation: Preliminary evidence for an influx of immature cells into the bloodstream.

    Science.gov (United States)

    Turner, J E; Spielmann, G; Wadley, A J; Aldred, S; Simpson, R J; Campbell, J P

    2016-10-01

    The number of peripheral blood B lymphocytes doubles during acute exercise, but the phenotypic composition of this response remains unknown. In two independent exercise studies, using complimentary phenotyping strategies, we investigated the mobilisation patterns of distinct B cell subsets. In study one, nine healthy males (mean±SD age: 22.1±3.4years) completed a continuous cycling bout at 80% V̇O2MAX for 20min. In study two, seven healthy experienced cyclists (mean±SD age: 29.9±4.7years) completed a 30min cycling trial at a workload corresponding to +5% of the individual blood lactate threshold. In study one, CD3-CD19+ B cell subsets were classified into immature (CD27-CD10+), naïve (CD27-CD10-), memory (CD27+CD38-), plasma cells/plasmablasts (CD27+CD38+) and finally, recently purported 'B1' cells (CD27+ CD43+ CD69-). In study two, CD20+ B cells were classified into immature (CD27-IgD-), naïve (CD27-IgD+), and IgM+/IgG+/IgA+ memory cells (CD27+IgD-). Total B cells exhibited a mean increase of 88% (study one) and 60% (study two) during exercise. In both studies, immature cells displayed the greatest increase, followed by memory cells, then naïve cells (study one: immature 130%>mature 105%>naïve 84%; study two: immature 110%>mature 56%>naïve 38%). Our findings show that, unlike T cells and NK cells, B cell mobilisation is not driven by effector status, and, for the first time, that B cell mobilisation during exercise is comprised of immature CD27- IgD-/CD10+ cells.

  6. Further evidence that paroxysmal nocturnal haemoglobinuria is a disorder of defective cell membrane lipid rafts.

    Science.gov (United States)

    Ratajczak, Mariusz Z; Borkowska, Sylwia; Mierzejewska, Kasia; Kucia, Magda; Mendek-Czajkowska, Ewa; Suszynska, Malwina; Sharma, Vivek A; Deptala, Andrzej; Song, Wechao; Platzbecker, Uwe; Larratt, Loree; Janowska-Wieczorek, Anna; Maciejewski, Jarek; Ratajczak, Janina

    2015-09-01

    The glycolipid glycosylphosphatidylinositol anchor (GPI-A) plays an important role in lipid raft formation, which is required for proper expression on the cell surface of two inhibitors of the complement cascade, CD55 and CD59. The absence of these markers from the surface of blood cells, including erythrocytes, makes the cells susceptible to complement lysis, as seen in patients suffering from paroxysmal nocturnal haemoglobinuria (PNH). However, the explanation for why PNH-affected hematopoietic stem/progenitor cells (HSPCs) expand over time in BM is still unclear. Here, we propose an explanation for this phenomenon and provide evidence that a defect in lipid raft formation in HSPCs leads to defective CXCR4- and VLA-4-mediated retention of these cells in BM. In support of this possibility, BM-isolated CD34(+) cells from PNH patients show a defect in the incorporation of CXCR4 and VLA-4 into membrane lipid rafts, respond weakly to SDF-1 stimulation, and show defective adhesion to fibronectin. Similar data were obtained with the GPI-A(-) Jurkat cell line. Moreover, we also report that chimeric mice transplanted with CD55(-/-)  CD59(-/-) BM cells but with proper GPI-A expression do not expand over time in transplanted hosts. On the basis of these findings, we propose that a defect in lipid raft formation in PNH-mutated HSPCs makes these cells more mobile, so that they expand and out-compete normal HSPCs from their BM niches over time.

  7. 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.

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

    DEFF Research Database (Denmark)

    Skou, Rikke Birgitte Lyngaa; 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...... the MCPyV oncoprotein large T and small T antigens and the virus capsid protein VP1 for potential T-cell epitopes, and tested for MHC class I affinity. We confirmed the relevance of these epitopes using a high-throughput platform for T-cell enrichment and combinatorial encoding of MHC class I multimers...

  9. Strigolactone analogues induce apoptosis through activation of p38 and the stress response pathway in cancer cell lines and in conditionally reprogrammed primary prostate cancer cells.

    Science.gov (United States)

    Pollock, Claire B; McDonough, Sara; Wang, Victor S; Lee, Hyojung; Ringer, Lymor; Li, Xin; Prandi, Cristina; Lee, Richard J; Feldman, Adam S; Koltai, Hinanit; Kapulnik, Yoram; Rodriguez, Olga C; Schlegel, Richard; Albanese, Christopher; Yarden, Ronit I

    2014-03-30

    Strigolactones are a novel class of plant hormones produced in roots and regulate shoot and root development. We have previously shown that synthetic strigolactone analogues potently inhibit growth of breast cancer cells and breast cancer stem cells. Here we show that strigolactone analogues inhibit the growth and survival of an array of cancer-derived cell lines representing solid and non-solid cancer cells including: prostate, colon, lung, melanoma, osteosarcoma and leukemic cell lines, while normal cells were minimally affected. Treatment of cancer cells with strigolactone analogues was hallmarked by activation of the stress-related MAPKs: p38 and JNK and induction of stress-related genes; cell cycle arrest and apoptosis evident by increased percentages of cells in the sub-G1 fraction and Annexin V staining. In addition, we tested the response of patient-matched conditionally reprogrammed primary prostate normal and cancer cells. The tumor cells exhibited significantly higher sensitivity to the two most potent SL analogues with increased apoptosis confirmed by PARP1 cleavage compared to their normal counterpart cells. Thus, Strigolactone analogues are promising candidates for anticancer therapy by their ability to specifically induce cell cycle arrest, cellular stress and apoptosis in tumor cells with minimal effects on growth and survival of normal cells.

  10. 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.

  11. 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.

  12. Antigen-Specific B Cells Reactivate an Effective Cytotoxic T Cell Response against Phagocytosed Salmonella through Cross-Presentation

    NARCIS (Netherlands)

    de Wit, J.; Souwer, Y.; Jorritsma, T.; Bos, H.; ten Brinke, A.; Neefjes, J.; Ham, S.M.

    2010-01-01

    Background: The eradication of facultative intracellular bacterial pathogens, like Salmonella typhi, requires the concerted action of both the humoral immune response and the cytotoxic CD8(+) T cell response. Dendritic cells (DCs) are considered to orchestrate the cytotoxic CD8(+) T cell response vi

  13. 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.

  14. 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.

  15. Modulation of T cell response by Phellinus linteus.

    Science.gov (United States)

    Lin, Chun-Jung; Lien, Hsiu-Man; Lin, Hwai-Jeng; Huang, Chao-Lu; Kao, Min-Chuan; Chen, Yu-An; Wang, Chien-Kuo; Chang, Hsiao-Yun; Chang, Yin-Kuang; Wu, Hua-Shan; Lai, Chih-Ho

    2016-01-01

    Phellinus linteus, a species of mushroom, has been shown to contribute to health benefits, such as anti-inflammatory activity and immunomodulatory efficacy. The aim of this study was to analyze the most effective constituents of P. linteus fermented broths, polysaccharides, and to evaluate their immunoregulatory effects on T cells. Four fermented broths (PL1-4) and the dialyzate medium (MD) were prepared from P. linteus mycelia, and the polysaccharide contents of each were analyzed. The P. linteus samples were tested for biological activity in the regulation of T cell activation. In T cells, the production of mitogen-induced interleukin (IL)-2 and cell cycle progression were dose-responsively inhibited by PL3 and MD, primarily through cell-cycle arrest in S phase. PL3 broth, which contained large quantities of polysaccharides, significantly decreased the ratio of interferon-gamma (IFN-γ) to interleukin 4 (IL-4) in T cells. Thus, P. linteus fermented broths produced additive effects on the regulation of the Th1/Th2 balance and show promise for the development of immunomodulatory therapeutics.

  16. Matrix Stiffness Modulates Proliferation, Chemotherapeutic Response and Dormancy in Hepatocellular Carcinoma Cells

    Science.gov (United States)

    Schrader, Jörg; Gordon-Walker, Timothy T; Aucott, Rebecca L; van Deemter, Mariëlle; Quaas, Alexander; Walsh, Shaun; Benten, Daniel; Forbes, Stuart J; Wells, Rebecca G; Iredale, John P

    2010-01-01

    There is increasing evidence that the physical environment is a critical mediator of tumor behavior. Hepatocellular carcinoma (HCC) develops within an altered biomechanical environment and increasing matrix stiffness is a strong predictor of HCC development. The aim of this study was to establish whether changes in matrix stiffness, which are characteristic of inflammation and fibrosis, regulate HCC cell proliferation and chemotherapeutic response. Using an in vitro system of “mechanically-tunable” matrix-coated polyacrylamide gels, matrix stiffness was modeled across a pathophysiologically-relevant range, corresponding to values encountered in normal and fibrotic livers. Results Increasing matrix stiffness was found to promote HCC cell proliferation. The proliferative index (assessed by Ki67 staining) of Huh7 and HepG2 cells was 2.7-fold and 12.2-fold higher, respectively, when the cells were cultured on stiff (12kPa) versus soft (1kPa) supports. This was associated with stiffness-dependent regulation of basal and HGF-stimulated mitogenic signaling through extracellular regulated kinase (ERK), protein kinase B (PKB/Akt) and signal transducer and activator of transcription 3 (STAT3). β1-integrin and focal adhesion kinase (FAK) were found to modulate stiffness-dependent HCC cell proliferation. Following treatment with cisplatin, we observed reduced apoptosis in HCC cells cultured on a stiff versus soft (physiological) supports. Interestingly, however, surviving cells from soft supports had significantly higher clonogenic capacity than surviving cells from a stiff microenvironment. This was associated with enhanced expression of cancer stem cell markers, including CD44, CD133, c-kit, CXCR4, octamer-4 (OCT4) and NANOG. Conclusion Increasing matrix stiffness promotes proliferation and chemotherapeutic resistance, whereas a soft environment induces reversible cellular dormancy and stem cell characteristics in HCC. This has implications for both the treatment of

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

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    Olga Momcilovic

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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

  18. Glycoarray Technologies: Deciphering Interactions from Proteins to Live Cell Responses

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    Tania M. Puvirajesinghe

    2016-01-01

    Full Text Available Microarray technologies inspired the development of carbohydrate arrays. Initially, carbohydrate array technology was hindered by the complex structures of glycans and their structural variability. The first designs of glycoarrays focused on the HTP (high throughput study of protein–glycan binding events, and subsequently more in-depth kinetic analysis of carbohydrate–protein interactions. However, the applications have rapidly expanded and now achieve successful discrimination of selective interactions between carbohydrates and, not only proteins, but also viruses, bacteria and eukaryotic cells, and most recently even live cell responses to immobilized glycans. Combining array technology with other HTP technologies such as mass spectrometry is expected to allow even more accurate and sensitive analysis. This review provides a broad overview of established glycoarray technologies (with a special focus on glycosaminoglycan applications and their emerging applications to the study of complex interactions between glycans and whole living cells.

  19. Organizational changes to thyroid regulation in Alligator mississippiensis: evidence for predictive adaptive responses.

    Directory of Open Access Journals (Sweden)

    Ashley S P Boggs

    Full Text Available During embryonic development, organisms are sensitive to changes in thyroid hormone signaling which can reset the hypothalamic-pituitary-thyroid axis. It has been hypothesized that this developmental programming is a 'predictive adaptive response', a physiological adjustment in accordance with the embryonic environment that will best aid an individual's survival in a similar postnatal environment. When the embryonic environment is a poor predictor of the external environment, the developmental changes are no longer adaptive and can result in disease states. We predicted that endocrine disrupting chemicals (EDCs and environmentally-based iodide imbalance could lead to developmental changes to the thyroid axis. To explore whether iodide or EDCs could alter developmental programming, we collected American alligator eggs from an estuarine environment with high iodide availability and elevated thyroid-specific EDCs, a freshwater environment contaminated with elevated agriculturally derived EDCs, and a reference freshwater environment. We then incubated them under identical conditions. We examined plasma thyroxine and triiodothyronine concentrations, thyroid gland histology, plasma inorganic iodide, and somatic growth at one week (before external nutrition and ten months after hatching (on identical diets. Neonates from the estuarine environment were thyrotoxic, expressing follicular cell hyperplasia (p = 0.01 and elevated plasma triiodothyronine concentrations (p = 0.0006 closely tied to plasma iodide concentrations (p = 0.003. Neonates from the freshwater contaminated site were hypothyroid, expressing thyroid follicular cell hyperplasia (p = 0.01 and depressed plasma thyroxine concentrations (p = 0.008. Following a ten month growth period under identical conditions, thyroid histology (hyperplasia p = 0.04; colloid depletion p = 0.01 and somatic growth (body mass p<0.0001; length p = 0.02 remained altered among the

  20. Evidence for oxidative stress and defective antioxidant response in guinea pigs with tuberculosis.

    Directory of Open Access Journals (Sweden)

    Gopinath S Palanisamy

    Full Text Available The development of granulomatous inflammation with caseous necrosis is an important but poorly understood manifestation of tuberculosis in humans and some animal models. In this study we measured the byproducts of oxidative stress in granulomatous lesions as well as the systemic antioxidant capacity of BCG vaccinated and non-vaccinated guinea pigs experimentally infected with Mycobacterium tuberculosis. In non-vaccinated guinea pigs, oxidative stress was evident within 2 weeks of infection as measured by a decrease in the serum total antioxidant capacity and blood glutathione levels accompanied by an increase in malondialdehyde, a byproduct of lipid peroxidation, within lesions. Despite a decrease in total and reduced blood glutathione concentrations, there was an increase in lesion glutathione by immunohistochemistry in response to localized oxidative stress. In addition there was an increase in the expression of the host transcription factor nuclear erythroid 2 p45-related factor 2 (Nrf2, which regulates several protein and non-proteins antioxidants, including glutathione. Despite the increase in cytoplasmic expression of Nrf2, immunohistochemical staining revealed a defect in Nrf2 nuclear translocation within granulomatous lesions as well as a decrease in the expression of the Nrf2-regulated antioxidant protein NQO1. Treating M. tuberculosis-infected guinea pigs with the antioxidant drug N-acetyl cysteine (NAC partially restored blood glutathione concentrations and the serum total antioxidant capacity. Treatment with NAC also decreased spleen bacterial counts, as well as decreased the lung and spleen lesion burden and the severity of lesion necrosis. These data suggest that the progressive oxidative stress during experimental tuberculosis in guinea pigs is due in part to a defect in host antioxidant defenses, which, we show here, can be partially restored with antioxidant treatment. These data suggest that the therapeutic strategies that

  1. Effects of spatial response coding on distractor processing: evidence from auditory spatial negative priming tasks with keypress, joystick, and head movement responses.

    Science.gov (United States)

    Möller, Malte; Mayr, Susanne; Buchner, Axel

    2015-01-01

    Prior studies of spatial negative priming indicate that distractor-assigned keypress responses are inhibited as part of visual, but not auditory, processing. However, recent evidence suggests that static keypress responses are not directly activated by spatially presented sounds and, therefore, might not call for an inhibitory process. In order to investigate the role of response inhibition in auditory processing, we used spatially directed responses that have been shown to result in direct response activation to irrelevant sounds. Participants localized a target sound by performing manual joystick responses (Experiment 1) or head movements (Experiment 2B) while ignoring a concurrent distractor sound. Relations between prime distractor and probe target were systematically manipulated (repeated vs. changed) with respect to identity and location. Experiment 2A investigated the influence of distractor sounds on spatial parameters of head movements toward target locations and showed that distractor-assigned responses are immediately inhibited to prevent false responding in the ongoing trial. Interestingly, performance in Experiments 1 and 2B was not generally impaired when the probe target appeared at the location of the former prime distractor and required a previously withheld and presumably inhibited response. Instead, performance was impaired only when prime distractor and probe target mismatched in terms of location or identity, which fully conforms to the feature-mismatching hypothesis. Together, the results suggest that response inhibition operates in auditory processing when response activation is provided but is presumably too short-lived to affect responding on the subsequent trial.

  2. 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

  3. microRNA Response to Listeria monocytogenes Infection in Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Benjamin Izar

    2012-01-01

    Full Text Available 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 (∆inlAB or ∆hly 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 ∆inlAB 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.

  4. On the selection of words and oral motor responses: evidence of a response-independent fronto-parietal network.

    Science.gov (United States)

    Tremblay, Pascale; Gracco, Vincent L

    2010-01-01

    Several brain areas including the medial and lateral premotor areas, and the prefrontal cortex, are thought to be involved in response selection. It is unclear, however, what the specific contribution of each of these areas is. It is also unclear whether the response selection process operates independent of response modality or whether a number of specialized processes are recruited depending on the behaviour of interest. In the present study, the neural substrates for different response selection modes (volitional and stimulus-driven) were compared, using sparse-sampling functional magnetic resonance imaging, for two different response modalities: words and comparable oral motor gestures. Results demonstrate that response selection relies on a network of prefrontal, premotor and parietal areas, with the pre-supplementary motor area (pre-SMA) at the core of the process. Overall, this network is sensitive to the manner in which responses are selected, despite the absence of a medio-lateral axis, as was suggested by Goldberg (1985). In contrast, this network shows little sensitivity to the modality of the response, suggesting of a domain-general selection process. Theoretical implications of these results are discussed.

  5. 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

  6. Monosaccharide-responsive phenylboronate-polyol cell scaffolds for cell sheet and tissue engineering applications.

    Directory of Open Access Journals (Sweden)

    Rachamalla Maheedhar Reddy

    Full Text Available Analyte-responsive smart polymeric materials are of great interest and have been actively investigated in the field of regenerative medicine. Phenylboronate containing copolymers form gels with polyols under alkaline conditions. Monosaccharides, by virtue of their higher affinity towards boronate, can displace polyols and solubilize such gels. In the present study, we investigate the possibility of utilizing phenylboronate-polyol interactions at physiological pH in order to develop monosaccharide-responsive degradable scaffold materials for systems dealing with cells and tissues. Amine assisted phenylboronate-polyol interactions were employed to develop novel hydrogel and cryogel scaffolds at neutral pH. The scaffolds displayed monosaccharide inducible gel-sol phase transformability. In vitro cell culture studies demonstrated the ability of scaffolds to support cell adhesion, viability and proliferation. Fructose induced gel degradation is used to recover cells cultured on the hydrogels. The cryogels displayed open macroporous structure and superior mechanical properties. These novel phase transformable phenylboronate-polyol based scaffolds displayed a great potential for various cell sheet and tissue engineering applications. Their monosaccharide responsiveness at physiological pH is very useful and can be utilized in the fields of cell immobilization, spheroid culture, saccharide recognition and analyte-responsive drug delivery.

  7. 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.

  8. Human NK cells positively regulate gammadelta T cells in response to Mycobacterium tuberculosis.

    Science.gov (United States)

    Zhang, Ruijun; Zheng, Xiaodong; Li, Baiqing; Wei, Haiming; Tian, Zhigang

    2006-02-15

    The decrease in NK cell activity and the loss of gammadelta T cells in active pulmonary tuberculosis patients have been reported. In this study, we observed that the proliferating response of gammadelta T cells to the heat-treated Ags of Mycobacterium tuberculosis from different individuals was noted to be dependent on the content or function of NK cells in PBMC in a population study. We also found that NK cells were directly rapidly activated by the heat-treated Ags from M. tuberculosis (H37Ra) in vitro; in turn, the activated NK cells improved gammadelta T cell proliferation both by CD54-mediated cell-cell contact through the forming immune synapse and by soluble factors TNF-alpha, GM-CSF, and IL-12, but not IFN-gamma. Our results demonstrated that an interaction between NK cells and gammadelta T cells existed in antituberculosis immunity. Up-regulating the function of NK cells might be beneficial to the prevention and control of pulmonary tuberculosis.

  9. Functional signatures of human CD4 and CD8 T cell responses to Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Teresa ePrezzemolo

    2014-04-01

    Full Text Available With 1.4 million deaths and 8.7 million new cases in 2011, tuberculosis (TB remains a global health care problem and together with HIV and Malaria represents the one of the three infectious diseases world-wild. Control of the global TB epidemic has been impaired by the lack of an effective vaccine, by the emergence of drug-resistant forms of Mycobacterium tuberculosis (Mtb and by the lack of sensitive and rapid diagnostics. It is estimated, by epidemiological reports, that one third of the world’s population is latently infected with Mtb, but the majority of infected individuals develops long-lived protective immunity, which controls and contains Mtb in a T cell-dependent manner. Development of TB disease results from interactions among the environment, the host, and the pathogen, and known risk factors include HIV coinfection, immunodeficiency, diabetes mellitus, overcrowding, malnutrition, and general poverty; therefore an effective T cell response determines whether the infection resolves or develops into clinically evident disease. Consequently, there is great interest in determining which T cells subsets mediate anti-mycobacterial immunity, delineating their effector functions. On the other hand, many aspects remain unsolved in understanding why some individuals are protected from Mtb infection while others go on to develop disease.Several studies have demonstrated that CD4+ T cells are involved in protection against Mtb, as supported by the evidence that CD4+ T cell depletion is responsible for Mtb reactivation in HIV-infected individuals. There are many subsets of CD4+ T cells, such as T-helper 1 (Th1, Th2, Th17, and regulatory T cells (Tregs, and all these subsets cooperate or interfere with each other to control infection; the dominant subset may differ between active and latent Mtb infection cases. Mtb-specific CD4+ Th1 cell response is considered to have a protective role for the ability to produce cytokines such as IFN- or TNF

  10. Trafficking of osteonectin by retinal pigment epithelial cells: evidence for basolateral secretion.

    Science.gov (United States)

    Ratnayaka, Arjuna; Paraoan, Luminita; Nelson, Glyn; Spiller, Dave G; White, Michael R H; Hiscott, Paul

    2007-01-01

    Osteonectin is a glycoprotein that modulates several aspects of cellular behaviour including proliferation and adhesion. The retinal pigment epithelium forms a continuous monolayer of polarised cells immediately bellow the neuroretina, and is integral to the homeostasis of photoreceptor cells. While osteonectin is expressed by normal retinal pigment epithelium in situ, its expression is significantly increased in retinal pigment epithelial cells associated with several common retinal diseases. This pattern of expression implies an important role for osteonectin in the biology of retinal pigment epithelial cells. However, the trafficking, processing, and eventual fate of osteonectin in these cells is not clear at present. Although the theoretical report of a leader sequence within the osteonectin open reading frame and its extracellular presence in some tissues indirectly support secretion of the protein, there is no direct experimental demonstration of the secretion route to date. As a first step towards understanding the role of osteonectin in retinal pigment epithelium, we studied the intracellular distribution and trafficking of the protein in living cells. Here, we present experimental evidence that a precursor osteonectin fusion protein is targeted to the endoplasmic reticulum/Golgi pathway, with a likely basal secretion in retinal pigment epithelial cells. In addition, we show that the precursor osteonectin protein having the leader sequence masked fails to undergo secretion leading to cell death, a phenotype which may be of relevance not only for retinal pathology, but also for other diseases such as the bone disorder known as pseudoachondroplasia that is associated with a lack of osteonectin secretion.

  11. Cells involved in the immune response. XXIX Establishment of optimal conditions for the primary and secondary immune responses by rabbit lymphoid cells in vitro.

    Science.gov (United States)

    Richter, M; Behelak, Y

    1975-01-01

    Attempts were made to initiate the primary and secondary humoral immune responses to sheep red blood cells (SRBC) in vitro as determined by the hemolytic plaque-forming cell (PFC) response, with cell suspensions prepared from a variety of lymphoid organs of the rabbit- thymus, bone marrow, spleen, appendix, sacculus rotundus, Peyer's patches, popliteal lymph node and circulating leukocytes. A number of different media and gaseous phases were utilized in order to establish the optimal conditions for the immune response in vitro. The induction of a secondary PFC response was consistently obtained with 'memory' spleen cells obtained from rabbits 3-6 months following intravenous immunization with SRBC but not with cells of any of the other lymphoid organs, and this response probably represents the activity of memory cells which reside in the rabbit spleen. A primary response was observed only with 'normal' spleen cells, and the medium which faciliated the response was different from that which facilitated the induction of the secondary response in vitro. It was also observed, using a medium in which normal spleen cells were incapable of generating PFC', that mixed cultures of normal spleen and normal appendix or bone marrow cells could give a marked PFC reponse in vitro. Whether the PFC response to SRBCs obtained with the lymphoid cells of normal, unimmunized rabbits represent a true primary response, a secondary response, or a response of a different nature as a consequence of continuous subthreshold immunization of the rabbit with enteric microorganisms which cross-react with the antigen, remains to be determined. However, out initial successes with cultures consisting of cells of at least two distinct lymphoid organs in cases where the cells of any one of these organs could not respond, suggest that interaction of at least two functionally distinct cells is required and that the repsonse observed in vitro is probably a primary immune response.

  12. The Dendritic Cell Response to Classic, Emerging, and Homeostatic Danger Signals. Implications for Autoimmunity.

    Directory of Open Access Journals (Sweden)

    Paul Matthew Gallo

    2013-06-01

    Full Text Available Dendritic cells (DCs initiate and control immune responses, participate in the maintenance of immunological tolerance and are pivotal players in the pathogenesis of autoimmunity. In patients with autoimmune disease and in experimental animal models of autoimmunity, DCs show abnormalities in both numbers and activation state, expressing immunogenic levels of costimulatory molecules and pro-inflammatory cytokines. Exogenous and endogenous danger signals activate DCs to stimulate the immune response. Classic endogenous danger signals are released, activated, or secreted by host cells and tissues experiencing stress, damage, and non-physiologic cell death; and are therefore referred to as damage-associated molecular patterns (DAMPs. Some DAMPs are released from cells, where they are normally sequestered, during necrosis (e.g. heat shock proteins, uric acid, ATP, HMGB1, mitochondria-derived molecules. Others are actively secreted, like Type I Interferons. Here we discuss important DAMPs in the context of autoimmunity. For some, there is a clear pathogenic link (e.g. nucleic acids and lupus. For others, there is less evidence. Additionally, we explore emerging danger signals. These include inorganic materials and man-made technologies (e.g. nanomaterials developed as novel therapeutic approaches. Some nanomaterials can activate DCs and may trigger unintended inflammatory responses. Finally, we will review homeostatic danger signals, danger signals that do not derive directly from pathogens or dying cells but are associated with perturbations of tissue/cell homeostasis and may signal pathological stress. These signals, like acidosis, hypoxia and changes in osmolarity, also play a role in inflammation and autoimmunity.

  13. Effects of chrysotherapy on cell mediated immune response.

    Science.gov (United States)

    Lorber, A; Jackson, W H; Simon, T M

    1982-01-01

    Auranofin (AF) differs significantly from gold sodium thiomalate (GSTM) in formulation, i.e., aurous gold is stabilized by dual sulfur and phosphorus ligands, hydrophobic rather than hydrophilic characteristics, and lack of ionic charge. These attributes facilitate: oral absorption of AF, plasma membrane penetration, increase in intracellular lymphocyte gold concentration; and perhaps thereby influence lymphocyte function. AF treated subjects recorded prompt and sharp declines in mitogen-induced lymphoproliferative response (LMR) greater than 80%; suppressed response to skin testing with dinitrochlorobenezene (DNCB) in 11 of 14 subjects; and blebbing of lymphocyte membranes by scanning electron microscopy. In contrast, lymphocytes from a matched group of GSTM treated subjects recorded later onset and less suppression of LMR; normal response to DNCB skin testing; and did not manifest membrane blebbing. Accordingly, the therapeutic action of AF on immune response was observed in the 16 subjects receiving 6 mg/d of an average of 45 weeks to effect primarily cell mediated rather than humoral immune response when compared with a matched group of GSTM treated patients.

  14. Innate immune response to pulmonary contusion: Identification of cell-type specific inflammatory responses

    OpenAIRE

    Hoth, J. Jason; Wells, Jonathan D.; Yoza, Barbara K.; McCall, Charles E.

    2012-01-01

    Lung injury from pulmonary contusion is a common traumatic injury, predominantly seen after blunt chest trauma such as in vehicular accidents. The local and systemic inflammatory response to injury includes activation of innate immune receptors, elaboration of a variety inflammatory mediators, and recruitment of inflammatory cells to the injured lung. Using a mouse model of pulmonary contusion, we had previously shown that innate immune Toll like receptors 2 and 4 (TLR2 and TLR4) mediate the ...

  15. 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....

  16. 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.

  17. Response to Comment on "Worldwide evidence of a unimodal relationship between productivity and plant species richness".

    Science.gov (United States)

    Pither, Jason; Fraser, Lauchlan H; Jentsch, Anke; Sternberg, Marcelo; Zobel, Martin; Cahill, James; Beierkuhnlein, Carl; Bartha, Sándor; Bennett, Jonathan A; Boldgiv, Bazartseren; Brown, Leslie R; Cabido, Marcelo; Campetella, Giandiego; Carlyle, Cameron N; Chelli, Stefano; Csergő, Anna Mária; Diaz, Sandra; Enrico, Lucas; Ensing, David; Fidelis, Alessandra; Garris, Heath W; Henry, Hugh A L; Höhn, Maria; Klironomos, John; Koorem, Kadri; Lawrence-Lodge, Rachael; Manning, Peter; Mitchell, Randall J; Moora, Mari; Pillar, Valério D; Stotz, Gisela C; Sugiyama, Shu-ichi; Szentes, Szilárd; Tungalag, Radnaakhand; Undrakhbold, Sainbileg; Wellstein, Camilla; Zupo, Talita

    2016-01-29

    Tredennick et al. criticize one of our statistical analyses and emphasize the low explanatory power of models relating productivity to diversity. These criticisms do not detract from our key findings, including evidence consistent with the unimodal constraint relationship predicted by the humped-back model and evidence of scale sensitivities in the form and strength of the relationship.

  18. Iodine Alters Gene Expression in the MCF7 Breast Cancer Cell Line: Evidence for an Anti-Estrogen Effect of Iodine

    Directory of Open Access Journals (Sweden)

    Frederick R. Stoddard II, Ari D. Brooks, Bernard A. Eskin, Gregg J. Johannes

    2008-01-01

    Full Text Available The protective effects of iodine on breast cancer have been postulated from epidemiologic evidence and described in animal models. The molecular mechanisms responsible have not been identified but laboratory evidence suggests that iodine may inhibit cancer promotion through modulation of the estrogen pathway. To elucidate the role of iodine in breast cancer, the effect of Lugol's iodine solution (5% I2, 10% KI on gene expression was analyzed in the estrogen responsive MCF-7 breast cancer cell line. Microarray analysis identified 29 genes that were up-regulated and 14 genes that were down-regulated in response to iodine/iodide treatment. The altered genes included several involved in hormone metabolism as well as genes involved in the regulation of cell cycle progression, growth and differentiation. Quantitative RT-PCR confirmed the array data demonstrating that iodine/iodide treatment increased the mRNA levels of several genes involved in estrogen metabolism (CYP1A1, CYP1B1, and AKR1C1 while decreasing the levels of the estrogen responsive genes TFF1 and WISP2. This report presents the results of the first gene array profiling of the response of a breast cancer cell line to iodine treatment. In addition to elucidating our understanding of the effects of iodine/iodide on breast cancer, this work suggests that iodine/iodide may be useful as an adjuvant therapy in the pharmacologic manipulation of the estrogen pathway in women with breast cancer.

  19. Timing of CD8+ T Cell Responses in Relation to Commencement of Capillary Leakage in Children with Dengue

    OpenAIRE

    Dung, Nguyen Thi Phuong; Le Duyen, Huynh Thi; Thuy, Nguyen Thi; Van Ngoc, Tran; van Vinh Chau, Nguyen; Hien, Tran Tinh; Rowland-Jones, Sarah L.; Dong, Tao; Farrar, Jeremy; Wills, Bridget; Simmons, Cameron P.

    2010-01-01

    Immune activation is a feature of dengue hemorrhagic fever (DHF) and CD8+ T cell responses in particular have been suggested as having a role in the vasculopathy that characterizes this disease. By phenotyping CD8+ T cells (CD38+/HLA-DR+, CD38+/Ki-67+, or HLA-DR+/Ki-67+) in serial blood samples from children with dengue, we found no evidence of increased CD8+ T cell activation prior to the commencement of resolution of viremia or hemoconcentration. Investigations with MHC class I tetramers to...

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Uhrf2 is important for DNA damage response in vascular smooth muscle cells.

    Science.gov (United States)

    Luo, Tao; Cui, Shijun; Bian, Chunjing; Yu, Xiaochun

    2013-11-08

    Emerging evidence shows that Uhrf1 plays an important role in DNA damage response for maintaining genomic stability. Interestingly, Uhrf1 has a paralog Uhrf2 in mammals. Uhrf1 and Uhrf2 share similar domain architectures. However, the role of Uhrf2 in DNA damage response has not been studied yet. During the analysis of the expression level of Uhrf2 in different tissues, we found that Uhrf2 is highly expressed in aorta and aortic vascular smooth muscle cells. Thus, we studied the role of Uhrf2 in DNA damage response in aortic vascular smooth muscle cells. Using laser microirradiation, we found that like Uhrf1, Uhrf2 was recruited to the sites of DNA damage. We dissected the functional domains of Uhrf2 and found that the TTD, PHD and SRA domains are important for the relocation of Uhrf2 to the sites of DNA damage. Moreover, depletion of Uhrf2 suppressed DNA damage-induced H2AX phosphorylation and DNA damage repair. Taken together, our results demonstrate the function of Uhrf2 in DNA damage response.

  2. 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

  3. 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.

  4. How B cells shape the immune response against Mycobacterium tuberculosis.

    Science.gov (United States)

    Maglione, Paul J; Chan, John

    2009-03-01

    Extensive work illustrating the importance of cellular immune mechanisms for protection against Mycobacterium tuberculosis has largely relegated B-cell biology to an afterthought within the tuberculosis (TB) field. However, recent studies have illustrated that B lymphocytes, through a variety of interactions with the cellular immune response, play previously underappreciated roles in shaping host defense against non-viral intracellular pathogens, including M. tuberculosis. Work in our laboratory has recently shown that, by considering these lymphocytes more broadly within their variety of interactions with cellular immunity, B cells have a significant impact on the outcome of airborne challenge with M. tuberculosis as well as the resultant inflammatory response. In this review, we advocate for a revised view of TB immunology in which roles of cellular and humoral immunity are not mutually exclusive. In the context of our current understanding of host defense against non-viral intracellular infections, we review recent data supporting a more significant role of B cells during M. tuberculosis infection than previously thought.

  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. Sexual dimorphism in epigenomic responses of stem cells to extreme fetal growth.

    Science.gov (United States)

    Delahaye, Fabien; Wijetunga, N Ari; Heo, Hye J; Tozour, Jessica N; Zhao, Yong Mei; Greally, John M; Einstein, Francine H

    2014-10-10

    Extreme fetal growth is associated with increased susceptibility to a range of adult diseases through an unknown mechanism of cellular memory. We tested whether heritable epigenetic processes in long-lived CD34(+) haematopoietic stem/progenitor cells showed evidence for re-programming associated with the extremes of fetal growth. Here we show that both fetal growth restriction and over-growth are associated with global shifts towards DNA hypermethylation, targeting cis-regulatory elements in proximity to genes involved in glucose homeostasis and stem cell function. We find a sexually dimorphic response; intrauterine growth restriction is associated with substantially greater epigenetic dysregulation in males, whereas large for gestational age growth predominantly affects females. The findings are consistent with extreme fetal growth interacting with variable fetal susceptibility to influence cellular ageing and metabolic characteristics through epigenetic mechanisms, potentially generating biomarkers that could identify infants at higher risk for chronic disease later in life.

  7. 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.

  8. Evidence of progenitor cells of glandular and myoepithelial cell lineages in the human adult female breast epithelium: a new progenitor (adult stem) cell concept.

    Science.gov (United States)

    Boecker, Werner; Buerger, Horst

    2003-10-01

    Although experimental data clearly confirm the existence of self-renewing mammary stem cells, the characteristics of such progenitor cells have never been satisfactorily defined. Using a double immunofluorescence technique for simultaneous detection of the basal cytokeratin 5, the glandular cytokeratins 8/18 and the myoepithelial differentiation marker smooth muscle actin (SMA), we were able to demonstrate the presence of CK5+ cells in human adult breast epithelium. These cells have the potential to differentiate to either glandular (CK8/18+) or myoepithelial cells (SMA+) through intermediary cells (CK5+ and CK8/18+ or SMA+). We therefore proceeded on the assumption that the CK5+ cells are phenotypically and behaviourally progenitor (committed adult stem) cells of human breast epithelium. Furthermore, we furnish evidence that most of these progenitor cells are located in the luminal epithelium of the ductal lobular tree. Based on data obtained in extensive analyses of proliferative breast disease lesions, we have come to regard usual ductal hyperplasia as a progenitor cell-derived lesion, whereas most breast cancers seem to evolve from differentiated glandular cells. Double immunofluorescence experiments provide a new tool to characterize phenotypically progenitor (adult stem) cells and their progenies. This model has been shown to be of great value for a better understanding not only of normal tissue regeneration but also of proliferative breast disease. Furthermore, this model provides a new tool for unravelling further the regulatory mechanisms that govern normal and pathological cell growth.

  9. 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

  10. Oral vaccination with lipid-formulated BCG induces a long-lived, multifunctional CD4(+ T cell memory immune response.

    Directory of Open Access Journals (Sweden)

    Lindsay R Ancelet

    Full Text Available Oral delivery of BCG in a lipid formulation (Liporale™-BCG targets delivery of viable bacilli to the mesenteric lymph nodes and confers protection against an aerosol Mycobacterium tuberculosis challenge. The magnitude, quality and duration of the effector and memory immune response induced by Liporale™-BCG vaccination is unknown. Therefore, we compared the effector and memory CD4(+ T cell response in the spleen and lungs of mice vaccinated with Liporale™-BCG to the response induced by subcutaneous BCG vaccination. Liporale™-BCG vaccination induced a long-lived CD4(+ T cell response, evident by the detection of effector CD4(+ T cells in the lungs and a significant increase in the number of Ag85B tetramer-specific CD4(+ T cells in the spleen up to 30 weeks post vaccination. Moreover, following polyclonal stimulation, Liporale™-BCG vaccination, but not s.c. BCG vaccination, induced a significant increase in both the percentage of CD4(+ T cells in the lungs capable of producing IFNγ and the number of multifunctional CD4(+ T cells in the lungs at 30 weeks post vaccination. These results demonstrate that orally delivered Liporale™-BCG vaccine induces a long-lived multifunctional immune response, and could therefore represent a practical and effective means of delivering novel BCG-based TB vaccines.

  11. Evidence of distinct tumour-propagating cell populations with different properties in primary human hepatocellular carcinoma.

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    Federico Colombo

    Full Text Available BACKGROUND AND AIMS: Increasing evidence that a number of malignancies are characterised by tumour cell heterogeneity has recently been published, but there is still a lack of data concerning liver cancers. The aim of this study was to investigate and characterise tumour-propagating cell (TPC compartments within human hepatocellular carcinoma (HCC. METHODS: After long-term culture, we identified three morphologically different tumour cell populations in a single HCC specimen, and extensively characterised them by means of flow cytometry, fluorescence microscopy, karyotyping and microarray analyses, single cell cloning, and xenotransplantation in NOD/SCID/IL2Rγ/⁻ mice. RESULTS: The primary cell populations (hcc-1, -2 and -3 and two clones generated by means of limiting dilutions from hcc-1 (clone-1/7 and -1/8 differently expressed a number of tumour-associated stem cell markers, including EpCAM, CD49f, CD44, CD133, CD56, Thy-1, ALDH and CK19, and also showed different doubling times, drug resistance and tumorigenic potential. Moreover, we found that ALDH expression, in combination with CD44 or Thy-1 negativity or CD56 positivity identified subpopulations with a higher clonogenic potential within hcc-1, hcc-2 and hcc-3 primary cell populations, respectively. Karyotyping revealed the clonal evolution of the cell populations and clones within the primary tumour. Importantly, the primary tumour cell population with the greatest tumorigenic potential and drug resistance showed more chromosomal alterations than the others and contained clones with epithelial and mesenchymal features. CONCLUSIONS: Individual HCCs can harbor different self-renewing tumorigenic cell types expressing a variety of morphological and phenotypical markers, karyotypic evolution and different gene expression profiles. This suggests that the models of hepatic carcinogenesis should take into account TPC heterogeneity due to intratumour clonal evolution.

  12. Transient Treg-cell depletion in adult mice results in persistent self-reactive CD4(+) T-cell responses.

    Science.gov (United States)

    Nyström, Sofia N; Bourges, Dorothée; Garry, Sarah; Ross, Ellen M; van Driel, Ian R; Gleeson, Paul A

    2014-12-01

    Depletion of Foxp3(+) CD4(+) regulatory T cells (Treg) in adults results in chronic inflammation and autoimmune disease. However, the impact of transient Treg-cell depletion on self-reactive responses is poorly defined. Here, we studied the effect of transient depletion of Treg cells on CD4(+) T-cell responses to endogenous self-antigens. Short-term ablation of Treg cells in mice resulted in rapid activation of CD4(+) T cells, increased percentage of IFN-γ(+) and Th17 cells in lymphoid organs, and development of autoimmune gastritis. To track self-reactive responses, we analyzed the activation of naïve gastric-specific CD4(+) T cells. There was a dramatic increase in proliferation and acquisition of effector function of gastric-specific T cells in the stomach draining LNs of Treg-cell-depleted mice, compared with untreated mice, either during Treg-cell depletion or after Treg-cell reconstitution. Moreover, the hyperproliferation of gastric-specific T cells in the Treg-cell-ablated mice was predominantly antigen-dependent. Transient depletion of Treg cells resulted in a shift in the ratio of peripheral:thymic Treg cells in the reemerged Treg-cell population, indicating an altered composition of Treg cells. These findings indicate that transient Treg-cell depletion results in ongoing antigen-driven self-reactive T-cell responses and emphasize the continual requirement for an intact Treg-cell population.

  13. 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.

  14. Tracking the elusive cytotoxic T cell response in pigs

    DEFF Research Database (Denmark)

    Jungersen, Gregers; Nielsen, Morten; Overgaard, Nana Haahr;

    Quantitative and qualitative assessment of antigen-specific cytotoxic T cell (CTL) responses in pigs is not a straightforward process. Through the years we have developed a series of reagents, tools and protocols to characterize peptide-specific CTL responses in pigs. The most common recombinant ...... SLA heavy chains were produced and peptide binding motifs were determined by assays measuring the affinity and stability of the peptide-SLA complex (pSLA) interaction. These results have been used to train neural networks to predict the binding of any pSLA (http......://www.cbs.dtu.dk/services/). Recombinant SLA molecules complexed with verified binding peptides can be assembled to SLA multimers for staining of peptide-specific CTLs, and measured by flow cytometry, as we have shown with FMDV and influenza. This, however, requires SLA-matched pigs for which we have developed two methods: a sequence...

  15. Diet-induced obesity reduces the responsiveness of the peripheral taste receptor cells.

    Directory of Open Access Journals (Sweden)

    Amanda B Maliphol

    Full Text Available INTRODUCTION: Obesity is a growing epidemic that causes many serious health related complications. While the causes of obesity are complex, there is conclusive evidence that overconsumption coupled with a sedentary lifestyle is the primary cause of this medical condition. Dietary consumption is controlled by appetite which is in turn regulated by multiple neuronal systems, including the taste system. However, the relationship between taste and obesity has not been well defined. Growing evidence suggests that taste perception in the brain is altered in obese animals and humans, however no studies have determined if there are altered taste responses in the peripheral taste receptor cells, which is the initiation site for the detection and perception of taste stimuli. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we used C57Bl/6 mice which readily become obese when placed on a high fat diet. After ten weeks on the high fat diet, we used calcium imaging to measure how taste-evoked calcium signals were affected in the obese mice. We found that significantly fewer taste receptor cells were responsive to some appetitive taste stimuli while the numbers of taste cells that were sensitive to aversive taste stimuli did not change. Properties of the taste-evoked calcium signals were also significantly altered in the obese mice. Behavioral analyses found that mice on the high fat diet had reduced ability to detect some taste stimuli compared to their littermate controls. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that diet-induced obesity significantly influences peripheral taste receptor cell signals which likely leads to changes in the central taste system and may cause altered taste perception.

  16. Identification of genes responsive to apoptosis in HL-60 cells

    Institute of Scientific and Technical Information of China (English)

    Wei JIN; Le-feng QU; Ping MIN; Shan CHEN; Hong LI; He LU; Yong-tai HOU

    2004-01-01

    AIM: To identify genes responsive to apoptosis in HL-60 cells treated by homoharringtonine. METHODS: cDNA microarray technology was used to detect gene expression and the result of microarrays for genes (TIEG and VDUP1) was confirmed by Northern analysis. RESULTS: Seventy-five individual mRNAs whose mass changed significantly were identified. Among these genes (25 were up-regulated and 50 were down-regulated), most are known related to oncogenes and tumor suppressor. Some genes were involved in apoptosis signaling pathways.CONCLUSION: TGFβ and TNF apoptosis signaling pathways were initiated during apoptosis in HL-60 cells.TIEG and VDUP1 play important roles in mediating apoptosis.

  17. In vitro antitumor immune response induced by fusion of dendritic cells and colon cancer cells

    Institute of Scientific and Technical Information of China (English)

    Feng Xu; Ying-Jiang Ye; Shan Wang

    2004-01-01

    AIM: The prevention of recurrence of colon cancer (CC)after operation is very important for improvement of the prognosis of CC patients, especially those with micrometastasis. The generation of fused cells between dendritic cells (DCs) and tumor cells maybe an effective approach for tumor antigen presentation in immunotherapy. In this study,we fused human colon caner SW480 cells and human peripheral blood - derived DCs to induce an antitumor activity against human CC.METHODS: CC SW480 cells and human peripheral blood derived DCs were fused with 500 mL/L polyethylene glycol (PEG).RESULTS: The specific T cell responses activated by fusion cells (FCs), were observed. About 100 mL/L to 160 mL/L of the PEG-treated non-adherent cells with fluorescences were considered to be dendritomas that highly expressed the key molecules for antigen presentation in our five cases. In vitro studies showed that fusions effectively activated CD8+ T lymphocytes to secrete interferon-γ. The early apoptotic ratio of the colon cancer SW480 cells was higher than that of controls, which was affected by cytotoxic T lymphocytes (CTLs) stimulated by dendritomas.CONCLUSION: The data indicate that fusion of tumor cells with DCs is an attractive strategy to induce tumor rejection.

  18. The Role of MicroRNAs in Regulatory T Cells and in the Immune Response.

    Science.gov (United States)

    Ha, Tai-You

    2011-02-01

    The discovery of microRNA (miRNA) is one of the major scientific breakthroughs in recent years and has revolutionized current cell biology and medical science. miRNAs are small (19~25nt) noncoding RNA molecules that post-transcriptionally regulate gene expression by targeting the 3' untranslated region (3'UTR) of specific messenger RNAs (mRNAs) for degradation of translation repression. Genetic ablation of the miRNA machinery, as well as loss or degradation of certain individual miRNAs, severely compromises immune development and response, and can lead to immune disorders. Several sophisticated regulatory mechanisms are used to maintain immune homeostasis. Regulatory T (Treg) cells are essential for maintaining peripheral tolerance, preventing autoimmune diseases and limiting chronic inflammatory diseases. Recent publications have provided compelling evidence that miRNAs are highly expressed in Treg cells, that the expression of Foxp3 is controlled by miRNAs and that a range of miRNAs are involved in the regulation of immunity. A large number of studies have reported links between alterations of miRNA homeostasis and pathological conditions such as cancer, cardiovascular disease and diabetes, as well as psychiatric and neurological diseases. Although it is still unclear how miRNA controls Treg cell development and function, recent studies certainly indicate that this topic will be the subject of further research. The specific circulating miRNA species may also be useful for the diagnosis, classification, prognosis of diseases and prediction of the therapeutic response. An explosive literature has focussed on the role of miRNA. In this review, I briefly summarize the current studies about the role of miRNAs in Treg cells and in the regulation of the innate and adaptive immune response. I also review the explosive current studies about clinical application of miRNA.

  19. B-Cell Depletion Therapy in Systemic Sclerosis: Experimental Rationale and Update on Clinical Evidence

    Directory of Open Access Journals (Sweden)

    Dimitrios Daoussis

    2011-01-01

    Full Text Available Systemic sclerosis (SSc is a systemic rheumatic disease with poor prognosis since therapeutic options are limited. Recent evidence from animal models suggests that B-cells may be actively involved in the fibrotic process. B-cells from tight skin mice, an animal model of scleroderma, display a “hyperresponsive” phenotype; treatment with rituximab (RTX significantly attenuates skin fibrosis in this animal model. In humans, B-cell infiltration is a prominent finding in most lung biopsies obtained from patients with SSc-associated interstitial lung disease. Several open label studies have assessed the clinical efficacy of RTX in SSc. In most patients skin fibrosis improved; lung function either improved or remained stable. Definite conclusions regarding the clinical efficacy of RTX in SSc cannot be drawn but further exploration with a multicenter, randomized study is warranted.

  20. Surveillance, response systems, and evidence updates on emerging zoonoses: the role of one health

    OpenAIRE

    2013-01-01

    Globally, emerging zoonotic diseases are increasing. Existing surveillance systems for zoonoses have substantial gaps, especially in developing countries, and the systems in place in the developed world require improvements. Resources and updates on evidence-based practice (EBP) for zoonoses are sparser in the veterinary literature as compared to the medical literature. Evidence updates for emerging zoonoses are either absent or rudimentary in both human and veterinary medicine. A ‘one-health...

  1. 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

  2. Evidence for a medial K+ recycling pathway from inner hair cells.

    Science.gov (United States)

    Spicer, S S; Schulte, B A

    1998-04-01

    K+ effluxed from outer hair cells and their nerves is thought to flow laterally to strial marginal cells for recycling into scala media. Observations reported here provide evidence that K+ effluxed from inner hair cells and inner radial nerves travels medially through border cells, inner sulcus cells (ISCs), limbal fibrocytes and interdental cells (IDCs) for return to endolymph. Morphologic features of ISCs in the medial route resembled those of Hensen and Claudius cells in the lateral indicating an ion transport role for ISCs like that of Hensen and Claudius cells. Na,K-ATPase in plasmalemma of IDCs testified to their capacity to resorb and transport K+ through their known gap junctions. IDCs were differentiated into three subgroups. The most lateral IDCs formed short and long columns. Long columns contacted the medialmost ISC inferiorly and the undersurface of the tectorial membrane superiorly providing thereby a potential transcellular route for K+ transit from ISCs to endolymph. Short columns faced inner sulcus below and tectorial membrane above and accordingly possessed cells with opposite polarity at the bottom and top of the column. Short columns thus appeared situated to resorb electrolytes from limbal stroma for release into inner sulcus and beneath tectorial membrane at opposite ends of the column. The central IDCs were positioned for resorbing and transporting K+ effluxing from the Na,K-ATPase-rich stellate fibrocytes which spread toward the IDCs from near the inner sulcus. The most medial IDCs lined cuplike invaginations near the attachment of Reissner's membrane and lay apposed to light fibrocytes located between supralimbal fibrocytes and the medial IDCs. Content of Na,K-ATPase and position in the K+ transport route likened the limbal stellate fibrocytes to the spiral ligament type II fibrocytes and supralimbal fibrocytes to suprastrial fibrocytes in the lateral wall. From content of creatine kinase and position in the transport path, limbal light

  3. Characterization of T cell mutants with defects in capacitative calcium entry: genetic evidence for the physiological roles of CRAC channels.

    Science.gov (United States)

    Fanger, C M; Hoth, M; Crabtree, G R; Lewis, R S

    1995-11-01

    Prolonged Ca2+ influx is an essential signal for the activation of T lymphocytes by antigen. This influx is thought to occur through highly selective Ca2+ release-activated Ca2+ (CRAC) channels that are activated by the depletion of intracellular Ca2+ stores. We have isolated mutants of the Jurkat human T cell line NZdipA to explore the molecular mechanisms that underlie capacitative Ca2+ entry and to allow a genetic test of the functions of CRAC channels in T cells. Five mutant cell lines (CJ-1 through CJ-5) were selected based on their failure to express a lethal diphtheria toxin A chain gene and a lacZ reporter gene driven by NF-AT, a Ca(2+)- and protein kinase C-dependent transcription factor. The rate of Ca2+ influx evoked by thapsigargin was reduced to varying degrees in the mutant cells whereas the dependence of NF-AT/lacZ gene transcription on [Ca2+]i was unaltered, suggesting that the transcriptional defect in these cells is caused by a reduced level of capacitative Ca2+ entry. We examined several factors that determine the rate of Ca2+ entry, including CRAC channel activity, K(+)-channel activity, and Ca2+ clearance mechanisms. The only parameter found to be dramatically altered in most of the mutant lines was the amplitude of the Ca2+ current (ICRAC), which ranged from 1 to 41% of that seen in parental control cells. In each case, the severity of the ICRAC defect was closely correlated with deficits in Ca2+ influx rate and Ca(2-)-dependent gene transcription. Behavior of the mutant cells provides genetic evidence for several roles of ICRAC in T cells. First, mitogenic doses of ionomycin appear to elevate [Ca2+]i primarily by activating CRAC channels. Second, ICRAC promotes the refilling of empty Ca2+ stores. Finally, CRAC channels are solely responsible for the Ca2+ influx that underlies antigen-mediated T cell activation. These mutant cell lines may provide a useful system for isolating, expressing, and exploring the functions of genes involved in

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

    Science.gov (United States)

    Lee, Jeeyong; Kim, Mi-Ra; Kim, Hyun-Ji; An, You Sun; Yi, Jae Youn

    2016-08-01

    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.

  5. Proteomic analysis of rice endosperm cells in response to expression of hGM-CSF.

    Science.gov (United States)

    Luo, Junling; Ning, Tingting; Sun, Yunfang; Zhu, Jinghua; Zhu, Yingguo; Lin, Qishan; Yang, Daichang

    2009-02-01

    The accumulation of significant levels of transgenic products in plant cells is required not only for crop improvement, but also for molecular pharming. However, knowledge about the fate of transgenic products and endogenous proteins in grain cells is lacking. Here, we utilized a quantitative mass spectrometry-based proteomic approach for comparative analysis of expression profiles of transgenic rice endosperm cells in response to expression of a recombinant pharmaceutical protein, human granulocyte-macrophage colony stimulation factor (hGM-CSF). This study provided the first available evidence concerning the fate of exogenous and endogenous proteins in grain cells. Among 1883 identified proteins with a false positive rate of 5%, 103 displayed significant changes (p-value < 0.05) between the transgenic and the wild-type endosperm cells. Notably, endogenous storage proteins and most carbohydrate metabolism-related proteins were down-regulated, while 26S proteasome-related proteins and chaperones were up-regulated in the transgenic rice endosperm. Furthermore, it was observed that expression of hGM-CSF induced endoplasmic reticulum stress and activated the ubiquitin/26S-proteasome pathway, which led to ubiquitination of this foreign gene product in the transgenic rice endosperm.

  6. Autophagy in response to photodynamic therapy: cell survival vs. cell death

    Science.gov (United States)

    Oleinick, Nancy L.; Xue, Liang-yan; Chiu, Song-mao; Joseph, Sheeba

    2009-02-01

    Autophagy (or more properly, macroautophagy) is a pathway whereby damaged organelles or other cell components are encased in a double membrane, the autophagosome, which fuses with lysosomes for digestion by lysosomal hydrolases. This process can promote cell survival by removing damaged organelles, but when damage is extensive, it can also be a mechanism of cell death. Similar to the Kessel and Agostinis laboratories, we have reported the vigorous induction of autophagy by PDT; this was found in human breast cancer MCF-7 cells whether or not they were able to efficiently induce apoptosis. One way to evaluate the role of autophagy in PDT-treated cells is to silence one of the essential genes in the pathway. Kessel and Reiners silenced the Atg7 gene of murine leukemia L1210 cells using inhibitory RNA and found sensitization to PDT-induced cell death at a low dose of PDT, implying that autophagy is protective when PDT damage is modest. We have examined the role of autophagy in an epithelium-derived cancer cell by comparing parental and Atg7-silenced MCF-7 cells to varying doses of PDT with the phthalocyanine photosensitizer Pc 4. In contrast to L1210 cells, autophagy-deficient MCF-7 cells were more resistant to the lethal effects of PDT, as judged by clonogenic assays. A possible explanation for the difference in outcome for L1210 vs. MCF-7 cells is the greatly reduced ability of the latter to undergo apoptosis, a deficiency that may convert autophagy into a cell-death process even at low PDT doses. Experiments to investigate the mechanism(s) responsible are in process.

  7. Lack of evidence for superantigen activity of Toxoplasma gondii towards human T cells

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    A.L. Vallochi

    2001-08-01

    Full Text Available Toxoplasma gondii is an obligatory intracellular parasite whose life cycle may include man as an intermediate host. More than 500 million people are infected with this parasite worldwide. It has been previously reported that T. gondii contains a superantigen activity. The purpose of the present study was to determine if the putative superantigen activity of T. gondii would manifest towards human T cells. Peripheral blood mononuclear cells (PBMC from individuals with no previous contact with the parasite were evaluated for proliferation as well as specific Vß expansion after exposure to Toxoplasma antigens. Likewise, PBMC from individuals with the congenital infection were evaluated for putative Vß family deletions in their T cell repertoire. We also evaluated, over a period of one year, the PBMC proliferation pattern in response to Toxoplasma antigens in patients with recently acquired infection. Some degree of proliferation in response to T. gondii was observed in the PBMC from individuals never exposed to the parasite, accompanied by specific Vß expansion, suggesting a superantigen effect. However, we found no specific deletion of Vß (or Valpha families in the blood of congenitally infected individuals. Furthermore, PBMC from recently infected individuals followed up over a period of one year did not present a reduction of the Vß families that were originally expanded in response to the parasite antigens. Taken together, our data suggest that T. gondii does not have a strong superantigen activity on human T cells.

  8. 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.

  9. 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.

  10. [The Problems with Domestic Introduction of rTMS from the Three Viewpoints of Scientific Evidence, Specialty and Social Responsibility].

    Science.gov (United States)

    Shinosaki, Kazuhiro

    2015-01-01

    The domestic introduction of rTMS is expected as a new treatment option for treatment-resistant depression. I discussed some problems with the introduction from three viewpoints : scientific evidence, specialty, and social responsibility. I surveyed scientific evidence for rTMS regarding the action mechanism, effectiveness, side effects, and its positioning in the treatment guidelines. To secure the quality of rTMS treatment, I proposed rTMS guidelines, nurturing of the specialists, and a center hospital plan, and pointed out some medium-term problems after its introduction and the consistency of rTMS treatment and standard depression treatment. From the viewpoint of social responsibility, rTMS treatment should be a medical service covered by health insurance to avoid its misuse. We should prepare to overcome the public suspicion of brain stimulation treatment for mental disease.

  11. Dental pulp response to bacterial cell wall material.

    Science.gov (United States)

    Warfvinge, J; Dahlén, G; Bergenholtz, G

    1985-08-01

    Lipopolysaccharides (LPS) from Bacteroides oralis and Veillonella parvula and cell wall material from Lactobacillus casei were studied for their capacity to induce leukocyte migration in the dental pulp and in an implanted wound chamber. Three adult monkeys were challenged using lyophilized material sealed into buccal Class V cavities prepared in dentin. Pulp tissue responses were observed histologically eight and 72 hours after initiation of the experiment. Subjacent to cut dentinal tubules, bacterial materials induced polymorphonuclear leukocyte (PMN's) infiltration in the pulp tissue of the majority of test teeth examined. Responses were similar for the three bacterial test materials at both time periods. Topical applications of bovine serum albumin (BSA), used as a control, induced significantly less accumulation of PMN's. Assessments of induced exudate volumes and leukocyte densities in chambers implanted in rats showed comparable rankings with pulpal experiment between test (i.e., bacterial) and control (BSA) materials. Analysis of the data indicates that high-molecular-weight complexes of bacterial cell walls may adversely affect pulpal tissue across freshly exposed dentin.

  12. Mammalian stem cells reprogramming in response to terahertz radiation.

    Directory of Open Access Journals (Sweden)

    Jonathan Bock

    Full Text Available We report that extended exposure to broad-spectrum terahertz radiation results in specific changes in cellular functions that are closely related to DNA-directed gene transcription. Our gene chip survey of gene expression shows that whereas 89% of the protein coding genes in mouse stem cells do not respond to the applied terahertz radiation, certain genes are activated, while other are repressed. RT-PCR experiments with selected gene probes corresponding to transcripts in the three groups of genes detail the gene specific effect. The response was not only gene specific but also irradiation conditions dependent. Our findings suggest that the applied terahertz irradiation accelerates cell differentiation toward adipose phenotype by activating the transcription factor peroxisome proliferator-activated receptor gamma (PPARG. Finally, our molecular dynamics computer simulations indicate that the local breathing dynamics of the PPARG promoter DNA coincides with the gene specific response to the THz radiation. We propose that THz radiation is a potential tool for cellular reprogramming.

  13. Iron Availability Affects Phosphate Deficiency-Mediated Responses, and Evidence of Cross-Talk with Auxin and Zinc in Arabidopsis.

    Science.gov (United States)

    Rai, Vandna; Sanagala, Raghavendrarao; Sinilal, Bhaskaran; Yadav, Sandeep; Sarkar, Ananda K; Dantu, Prem Kumar; Jain, Ajay

    2015-06-01

    Phosphate (Pi) is pivotal for plant growth and development. Pi deficiency triggers local and systemically regulated adaptive responses in Arabidopsis thaliana. Inhibition of primary root growth (PRG) and retarded development of lateral roots (LRs) are typical local Pi deficiency-mediated responses of the root system. Expression of Pi starvation-responsive (PSR) genes is regulated systemically. Here, we report the differential influence of iron (Fe) availability on local and systemic sensing of Pi by Arabidopsis. P-Fe- condition disrupted local Pi sensing, resulting in an elongated primary root (PR). Altered Fe homeostasis in the lpsi mutant with aberration in local Pi sensing provided circumstantial evidence towards the role of Fe in the maintenance of Pi homeostasis. Reporter gene assays, expression analysis of auxin-responsive genes (ARGs) and root phenotyping of the arf7arf19 mutant demonstrated the role of Fe availability on local Pi deficiency-mediated LR development. In addition, Fe availability also exerted a significant influence on PSR genes belonging to different functional categories. Together, these results demonstrated a substantial influence of Fe availability on Pi deficiency-mediated responses of ontogenetically distinct traits of the root system and PSR genes. The study also provided evidence of cross-talk between Pi, Fe and Zn, highlighting a complex tripartite interaction amongst them for maintaining Pi homeostasis.

  14. Effects of meal size and composition on incretin, alpha-cell, and beta-cell responses

    DEFF Research Database (Denmark)

    Rijkelijkhuizen, Josina M; McQuarrie, Kelly; Girman, Cynthia J

    2009-01-01

    of beta-cell function and incremental areas under the curve of glucose, insulin, C-peptide, glucagon, GLP-1, and GIP were calculated. Mixed models and Friedman tests were used to test for differences in meal responses. The large CH-rich meal and fat-rich meal resulted in a slightly larger insulin response......The incretins glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) regulate postprandial insulin release from the beta-cells. We investigated the effects of 3 standardized meals with different caloric and nutritional content in terms of postprandial glucose......, insulin, glucagon, and incretin responses. In a randomized crossover study, 18 subjects with type 2 diabetes mellitus and 6 healthy volunteers underwent three 4-hour meal tolerance tests (small carbohydrate [CH]-rich meal, large CH-rich meal, and fat-rich meal). Non-model-based and model-based estimates...

  15. 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

  16. 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.

  17. Enhancement of Spectral Response of Dye-Sensitized Solar Cells

    Science.gov (United States)

    Chang, Shuai

    Dye-Sensitized solar cell (DSSC) is a class of third-generation solar devices. A notable feature of DSSC is that it can be manufactured by solution-based approach; this non-vacuum processing renders significant reduction in manufacturing costs. Different from conventional solar cells, in a DSSC, mesoporous semiconductor film with large surface areas is utilized for anchoring dye molecules, serving as light absorbing layer. Dye sensitizers play an important role in determining the final performance in DSSCs. Since the first highly-efficient DSSC was reported in 1991 sensitized by a ruthenium-based dye, numerous researchers have been focused on the development and characterization of various kinds of dyes for the applications in DSSCs. These include mainly metal complexes dyes, organic dyes, porphyrins and phthalocyanines dyes. The first part of my thesis work is to develop and test new dyes for DSSCs and a series of phenothiazine-based organic dyes and new porphyrin dyes are reported during the process. It has been realized that extending the response of dye sensitizers to a wider range of the solar spectrum is a key step in further improving the device efficiency. Typically, there are two ways for expanding the strong spectral response of DSSCs from visible to far red/NIR region. One approach is called co-sensitization. Herein, we demonstrate a new co-sensitization concept where small molecules is used to insert the interstitial site of between the pre-adsorbed large molecules. In this case, the co-adsorbed small ones is found to improve the light response and impede the back recombination, finally leading to the power conversion efficiency over 10% in conventional DSSC devices and a record-equaling efficiency of 9.2% in quasi-solid-state devices. I also implemented graphene sheets in the anode films for better charge transfer efficiency and break the energy conversion limit of co-sensitization in DSSCs. The optimal configuration between porphyrin dyes and

  18. An Unusual Metastatic Renal Cell Carcinoma with Maintained Complete Response to Sunitinib Treatment

    Directory of Open Access Journals (Sweden)

    Luis Chara

    2011-12-01

    Full Text Available Recently, metastatic renal cell carcinoma (mRCC treatment has changed dramatically with the onset of new therapies against molecular targets replacing immunotherapy as standard treatment. We report the case of a 49-year-old patient with a moderately differentiated renal clear cell carcinoma without extracapsular extension who underwent radical nephrectomy. Eight months after surgery, he developed a thyroid metastasis which was also treated surgically with a hemithyroidectomy. Seventy-five months after nephrectomy, the patient presented an upper gastrointestinal bleeding due to a duodenal metastasis that infiltrates the head of the pancreas. The treatment applied was surgery by duodenopancreatectomy, with positive surgical margins in the pathologic study. In addition to this, the extension study showed lung metastases requiring initiation of systemic treatment with sunitinib. The patient presented an excellent response to treatment, showing complete clinical and radiological response at 5 months of treatment (RECIST criteria and a disease-free survival of 48 months until now, without evidence of toxicity. RCC has the potential to metastasize to almost any location, but thyroid and duodenal metastases in RCC are extremely rare. Moreover, this case also highlights the good responses that can be achieved in terms of disease-free survival, low toxicity and quality of life in this new era of therapies against molecular targets.

  19. Noncanonical autophagy inhibits the autoinflammatory, lupus-like response to dying cells.

    Science.gov (United States)

    Martinez, Jennifer; Cunha, Larissa D; Park, Sunmin; Yang, Mao; Lu, Qun; Orchard, Robert; Li, Quan-Zhen; Yan, Mei; Janke, Laura; Guy, Cliff; Linkermann, Andreas; Virgin, Herbert W; Green, Douglas R

    2016-05-01

    Defects in clearance of dying cells have been proposed to underlie the pathogenesis of systemic lupus erythematosus (SLE). Mice lacking molecules associated with dying cell clearance develop SLE-like disease, and phagocytes from patients with SLE often display defective clearance and increased inflammatory cytokine production when exposed to dying cells in vitro. Previously, we and others described a form of noncanonical autophagy known as LC3-associated phagocytosis (LAP), in which phagosomes containing engulfed particles, including dying cells, recruit elements of the autophagy pathway to facilitate maturation of phagosomes and digestion of their contents. Genome-wide association studies have identified polymorphisms in the Atg5 (ref. 8) and possibly Atg7 (ref. 9) genes, involved in both canonical autophagy and LAP, as markers of a predisposition for SLE. Here we describe the consequences of defective LAP in vivo. Mice lacking any of several components of the LAP pathway show increased serum levels of inflammatory cytokines and autoantibodies, glomerular immune complex deposition, and evidence of kidney damage. When dying cells are injected into LAP-deficient mice, they are engulfed but not efficiently degraded and trigger acute elevation of pro-inflammatory cytokines but not anti-inflammatory interleukin (IL)-10. Repeated injection of dying cells into LAP-deficient, but not LAP-sufficient, mice accelerated the development of SLE-like disease, including increased serum levels of autoantibodies. By contrast, mice deficient in genes required for canonical autophagy but not LAP do not display defective dying cell clearance, inflammatory cytokine production, or SLE-like disease, and, like wild-type mice, produce IL-10 in response to dying cells. Therefore, defects in LAP, rather than canonical autophagy, can cause SLE-like phenomena, and may contribute to the pathogenesis of SLE.

  20. Hypoxia Affects the Structure of Breast Cancer Cell-Derived Matrix to Support Angiogenic Responses of Endothelial Cells.

    Science.gov (United States)

    Hielscher, Abigail; Qiu, Connie; Porterfield, Josh; Smith, Quinton; Gerecht, Sharon

    2013-01-01

    Hypoxia, a common feature of the tumor environment and participant in tumor progression, is known to alter gene and protein expression of several Extracellular Matrix (ECM) proteins, many of which have roles in angiogenesis. Previously, we reported that ECM deposited from co-cultures of Neonatal Fibroblasts (NuFF) with breast cancer cells, supported 3-dimensional vascular morphogenesis. Here, we sought to characterize the hypoxic ECM and to identify whether the deposited ECM induce angiogenic responses in Endothelial Cells (ECs). NuFF and MDA-MB-231 breast cancer cells were co-cultured, subjected to alternating cycles of 24 hours of 1% (hypoxia) and 21% (atmospheric) oxygen and de-cellularized for analyses of deposited ECM. We report differences in mRNA expression profiles of matrix proteins and crosslinking enzymes relevant to angiogenesis in hypoxia-exposed co-cultures. Interestingly, overt differences in the expression of ECM proteins were not detected in the de-cellularized ECM; however, up-regulation of the cell-binding fragment of fibronecin was observed in the conditioned media of hypoxic co-cultures. Ultrastructure analyses of the de-cellularized ECM revealed differences in fiber morphology with hypoxic fibers more compact and aligned, occupying a greater percent area and having larger diameter fibers than atmospheric ECM. Examining the effect of hypoxic ECM on angiogenic responses of ECs, morphological differences in Capillary-Like Structures (CLS) formed atop de-cellularized hypoxic and atmospheric ECM were not evident. Interestingly, we found that hypoxic ECM regulated the expression of angiogenic factors and matrix metalloproteinases in CLS. Overall, we report that in vitro, hypoxia does not alter the composition of the ECM deposited by co-cultures of NuFF/MDA-MB-231, but rather alters fiber morphology, and induces vascular expression of angiogenic growth factors and metalloproteinases. Taken together, these results have important implications for

  1. Surveillance, response systems, and evidence updates on emerging zoonoses: the role of one health.

    Science.gov (United States)

    Asokan, G V; Kasimanickam, Ramanathan K; Asokan, Vanitha

    2013-01-01

    Globally, emerging zoonotic diseases are increasing. Existing surveillance systems for zoonoses have substantial gaps, especially in developing countries, and the systems in place in the developed world require improvements. Resources and updates on evidence-based practice (EBP) for zoonoses are sparser in the veterinary literature as compared to the medical literature. Evidence updates for emerging zoonoses are either absent or rudimentary in both human and veterinary medicine. A 'one-health' concept, including a global signaling surveillance system for emerging zoonoses, will be essential for correct diagnoses, interventions, and public health strategies. An open access EBP platform supported by builders of EBP resources is urgently needed to counter emerging zoonoses.

  2. Responsibility for Financial Management in Primary Schools: Evidence from an English Local Authority

    Science.gov (United States)

    Fitzgerald, Sarah; Drake, Julie

    2013-01-01

    Financial management in primary schools has changed in the UK with the introduction of the Schools Financial Value Standard (SFVS). There is increasing delegation of financial responsibility to the management team in the school, increasing the role of the head teacher and the governing body as part of overall responsibility for the strategic…

  3. Placebo Response is Driven by UCS Revaluation: Evidence, Neurophysiological Consequences and a Quantitative Model.

    Science.gov (United States)

    Puviani, Luca; Rama, Sidita

    2016-07-20

    Despite growing scientific interest in the placebo effect and increasing understanding of neurobiological mechanisms, theoretical modeling of the placebo response remains poorly developed. The most extensively accepted theories are expectation and conditioning, involving both conscious and unconscious information processing. However, it is not completely understood how these mechanisms can shape the placebo response. We focus here on neural processes which can account for key properties of the response to substance intake. It is shown that placebo response can be conceptualized as a reaction of a distributed neural system within the central nervous system. Such a reaction represents an integrated component of the response to open substance administration (or to substance intake) and is updated through "unconditioned stimulus (UCS) revaluation learning". The analysis leads to a theorem, which proves the existence of two distinct quantities coded within the brain, these are the expected or prediction outcome and the reactive response. We show that the reactive response is updated automatically by implicit revaluation learning, while the expected outcome can also be modulated through conscious information processing. Conceptualizing the response to substance intake in terms of UCS revaluation learning leads to the theoretical formulation of a potential neuropharmacological treatment for increasing unlimitedly the effectiveness of a given drug.

  4. Elderly co-residence and the household responsibilities hypothesis : Evidence from Nanjing, China

    NARCIS (Netherlands)

    Feng, Jianxi; Dijst, Martin; Wissink, Bart; Prillwitz, Jan

    2015-01-01

    In this paper, we analyze the effects of co-residence with elderly parents on gender differences in travel. The Household Responsibility Hypothesis (HRH) explains differences in the role of women regarding household responsibilities. However, research so far has studied "Western" household types whi

  5. Societal Responses to Endemic Terror: Evidence from Driving Behavior in Israel

    Science.gov (United States)

    Stecklov, Guy; Goldstein, Joshua R.

    2010-01-01

    In this article, using data on traffic volume and fatal accident rates in Israel from 2001 to 2004--a period spanning much of the Second Intifada--we examine the population-level responses to endemic terror to uncover whether societies become habituated so that the response weakens following repeated attacks or whether they become increasingly…

  6. Predicting fluid responsiveness with transthoracic echocardiography is not yet evidence based

    DEFF Research Database (Denmark)

    Wetterslev, M; Haase, N; Johansen, R R;

    2013-01-01

    an integrated tool in the intensive care unit, this systematic review examined studies evaluating the predictive value of TTE for fluid responsiveness. In October 2012, we searched Pubmed, EMBASE and Web of Science for studies evaluating the predictive value of TTE-derived variables for fluid responsiveness...

  7. Stem cells and cancer: Evidence for bone marrow stem cells in epithelial cancers

    Institute of Scientific and Technical Information of China (English)

    Han-Chen Li; Calin Stoicov; Arlin B Rogers; JeanMarie Houghton

    2006-01-01

    Cancer commonly arises at the sites of chronic inflammation and infection. Although this association has long been recognized, the reason has remained unclear. Within the gastrointestinal tract, there are many examples of inflammatory conditions associated with cancer, and these include reflux disease and Barrett's adenocarcinoma of the esophagus, Helicobacter infection and gastric cancer, inflammatory bowel disease and colorectal cancer and viral hepatitis leading to hepatocellular carcinoma.There are several mechanisms by which chronic inflammation has been postulated to lead to cancer which includes enhanced proliferation in an endless attempt to heal damage, the presence of a persistent inflammatory environment creating a pro-carcinogenic environment and more recently a role for engraftment of circulating marrow-derived stem cells which may contribute to the stromal components of the tumor as well as the tumor mass itself. Here we review the recent advances in our understanding of the contributions of circulating bone marrow-derived stem cells to the formation of tumors in animal models as well as in human beings.

  8. Neurocognition as a Predictor of Response to Evidence-Based Psychosocial Interventions in Schizophrenia: What is the State of the Evidence?

    Science.gov (United States)

    Kurtz, Matthew M.

    2011-01-01

    Impairment in functional status is a hallmark of schizophrenia that has been linked to deficits in aspects of neurocognition (e.g., attention, memory, and problem-solving). A growing number of evidence-based behavioral interventions have been developed to address impairment in functional status, yet the relationships between these interventions and neurocognitive impairment are not well-understood. We conducted a synthetic, critical literature review of studies of performance on neurocognitive tests as a predictor of response to evidence-based behavioral treatment in schizophrenia. Behavioral treatments were selected based on the Patient Outcomes Research Team (PORT; Dixon et al., 2010) recommendations for practice and areas of emerging interest. Comprehensive searches of PsychINFO and MEDLINE/PUBMED databases identified 20 relevant studies. Results revealed that: (1) attention and memory measured at study entry were most frequently linked to proximal measures of progress in social skill training programs, (2) composite measures of neurocognitive function, as well attention, memory and problem-solving, were linked to progress in work therapy and supported employment programs, and comprehensive, integrated programs of psychosocial rehabilitation, while (3) baseline impairment on neurocogntive tests was not shown to limit progress in treatment studies of cognitive-behavioral therapy. The relevance of these findings for clinical practice and future research is discussed. PMID:21482324

  9. Concept mediation in trilingual translation: evidence from response time and repetition priming patterns.

    Science.gov (United States)

    Francis, Wendy S; Gallard, Sabrina L K

    2005-12-01

    Translation responses to individual words were elicited from 48 English-Spanish-French trilinguals, who translated in six directions at study and two directions at test. Patterns of translation response times and error rates at study reflected the relative proficiency of the trilinguals in comprehension and production of their three languages. At test, repeated items were translated more quickly than new items, with the strongest priming effects occurring for identical repetitions. Repetition priming was also substantial when only the stimulus language or only the response language matched from study to test, implying that repeated comprehension and production processes contribute to priming in translation. Patterns of response times and repetition priming indicate that translation in all directions involved conceptual access. Additive patterns in response time asymmetries and repetition priming were consistent with the treatment of word comprehension and production processes of translation as independent.

  10. SIRT1 inhibits inflammatory response partly through regulation of NLRP3 inflammasome in vascular endothelial cells.

    Science.gov (United States)

    Li, Yanxiang; Wang, Ping; Yang, Xiaofeng; Wang, Weirong; Zhang, Jiye; He, Yanhao; Zhang, Wei; Jing, Ting; Wang, Bo; Lin, Rong

    2016-09-01

    Emerging evidence has indicated that vascular endothelial cells (ECs) not only form the barrier between blood and the vessel wall but also serve as conditional innate immune cells. Our previous study found that SIRT1, a class III histone deacetylase, inhibits the inflammatory response in ECs. Recent studies revealed that SIRT1 also participates in the modulation of immune responses. Although the NLRP3 inflammasome is known to be a crucial component of the innate immune system, there is no direct evidence demonstrating the anti-inflammatory effect of SIRT1 on ECs through the NLRP3 inflammasome. In this study, we observed that lipopolysaccharide (LPS) and adenosine triphosphate (ATP) triggered the activation of NLRP3 inflammasome in human umbilical vein ECs (HUVECs). Moreover, SIRT1 expression was reduced in HUVECs stimulated with LPS and ATP. SIRT1 activator inhibited the expression of monocyte chemotactic protein-1 (MCP-1) and C-reactive protein (CRP), whereas SIRT1 knockdown resulted in significant increases in MCP-1 and CRP levels in HUVECs stimulated with LPS and ATP. Importantly, the lack of SIRT1 enhanced NLRP3 inflammasome activation and subsequent caspase-1 cleavage. On the other hand, NLRP3 siRNA blocked the activation of the NLRP3 inflammasome in HUVECs stimulated with LPS plus ATP. Further study revealed that NLRP3 inflammasome blockade significantly reduced MCP-1 and CRP production in HUVECs. In vivo studies indicated that implantation of the periarterial carotid collar inhibited arterial SIRT1 expression in rabbits. Meanwhile, treatment with a SIRT1 activator decreased the expression levels of MCP-1 and CRP in collared arteries and the interleukin (IL)-1β level in serum. Taken together, these findings indicate that NLRP3 inflammasome activation promoted endothelial inflammation and that SIRT1 inhibits the inflammatory response partly through regulation of the NLRP3 inflammasome in ECs.

  11. Ultrastructural evidence for the presence of crystalline structures in pig vaginal epithelial cells.

    Science.gov (United States)

    Gupta, P D; Sierralta, W D

    1994-01-01

    Terminally differentiated intermediate layers of vaginal epithelial cells from the late follicular phase of the pig show crystalline structures. Analysis of two dimensional images by transmission electron microscopy revealed that these structures are composed of rhomboid subunits. The longer side measures 26 nm whereas the smaller side measures 24 nm. The angles between the sides are 100 degrees and 80 degrees. These structures are not associated with any cellular structures and are not evident in other phases of the oestrous cycle. Structurally, they do not match with Reinke's crystals and are probably regulated by hormones.

  12. Bioluminescence Microscopy as a Method to Measure Single Cell Androgen Receptor Activity Heterogeneous Responses to Antiandrogens

    Science.gov (United States)

    Jain, Pallavi; Neveu, Bertrand; Velot, Lauriane; Wu, Lily; Fradet, Yves; Pouliot, Frédéric

    2016-01-01

    Cancer cell heterogeneity is well-documented. Therefore, techniques to monitor single cell heterogeneous responses to treatment are needed. We developed a highly translational and quantitative bioluminescence microscopy method to measure single cell androgen receptor (AR) activity modulation by antiandrogens from fluid biopsies. We showed that this assay can detect heterogeneous cellular response to drug treatment and that the sum of single cell AR activity can mirror the response in the whole cell population. This method may thus be used to monitor heterogeneous dynamic treatment responses in cancer cells. PMID:27678181

  13. 20 CFR 416.1014 - Responsibilities for obtaining evidence to make disability determinations.

    Science.gov (United States)

    2010-04-01

    ... make disability determinations. 416.1014 Section 416.1014 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL SECURITY INCOME FOR THE AGED, BLIND, AND DISABLED Determinations of Disability... sources, any evidence it needs to make a disability determination. (b) We will secure from the claimant...

  14. Innate immune response of human alveolar type II cells infected with severe acute respiratory syndrome-coronavirus.

    Science.gov (United States)

    Qian, Zhaohui; Travanty, Emily A; Oko, Lauren; Edeen, Karen; Berglund, Andrew; Wang, Jieru; Ito, Yoko; Holmes, Kathryn V; Mason, Robert J

    2013-06-01

    Severe acute respiratory syndrome (SARS)-coronavirus (CoV) produces a devastating primary viral pneumonia with diffuse alveolar damage and a marked increase in circulating cytokines. One of the major cell types to be infected is the alveolar type II cell. However, the innate immune response of primary human alveolar epithelial cells infected with SARS-CoV has not been defined. Our objectives included developing a culture system permissive for SARS-CoV infection in primary human type II cells and defining their innate immune response. Culturing primary human alveolar type II cells at an air-liquid interface (A/L) improved their differentiation and greatly increased their susceptibility to infection, allowing us to define their primary interferon and chemokine responses. Viral antigens were detected in the cytoplasm of infected type II cells, electron micrographs demonstrated secretory vesicles filled with virions, virus RNA concentrations increased with time, and infectious virions were released by exocytosis from the apical surface of polarized type II cells. A marked increase was evident in the mRNA concentrations of interferon-β and interferon-λ (IL-29) and in a large number of proinflammatory cytokines and chemokines. A surprising finding involved the variability of expression of angiotensin-converting enzyme-2, the SARS-CoV receptor, in type II cells from different donors. In conclusion, the cultivation of alveolar type II cells at an air-liquid interface provides primary cultures in which to study the pulmonary innate immune responses to infection with SARS-CoV, and to explore possible therapeutic approaches to modulating these innate immune responses.

  15. Effect Anticipation Affects Perceptual, Cognitive, and Motor Phases of Response Preparation: Evidence from an Event-Related Potential (ERP) Study.

    Science.gov (United States)

    Harrison, Neil R; Ziessler, Michael

    2016-01-01

    The anticipation of action effects is a basic process that can be observed even for key-pressing responses in a stimulus-response paradigm. In Ziessler et al.'s (2012) experiments participants first learned arbitrary effects of key-pressing responses. In the test phase an imperative stimulus determined the response, but participants withheld the response until a Go-stimulus appeared. Reaction times (RTs) were shorter if the Go-stimulus was compatible with the learned response effect. This is strong evidence that effect representations were activated during response planning. Here, we repeated the experiment using event-related potentials (ERPs), and we found that Go-stimulus locked ERPs depended on the compatibility relationship between the Go-stimulus and the response effect. In general, this supports the interpretation of the behavioral data. More specifically, differences in the ERPs between compatible and incompatible Go-stimuli were found for the early perceptual P1 component and the later frontal P2 component. P1 differences were found only in the second half of the experiment and for long stimulus onset asynchronies (SOAs) between imperative stimulus and Go-stimulus, i.e., when the effect was fully anticipated and the perceptual system was prepared for the effect-compatible Go-stimulus. P2 amplitudes, likely associated with evaluation and conflict detection, were larger when Go-stimulus and effect were incompatible; presumably, incompatibility increased the difficulty of effect anticipation. Onset of response-locked lateralized readiness potentials (R-LRPs) occurred earlier under incompatible conditions indicating extended motor processing. Together, these results strongly suggest that effect anticipation affects all (i.e., perceptual, cognitive, and motor) phases of response preparation.

  16. Effect anticipation affects perceptual, cognitive, and motor phases of response preparation: evidence from an event-related potential (ERP study

    Directory of Open Access Journals (Sweden)

    Neil Richard Harrison

    2016-01-01

    Full Text Available The anticipation of action effects is a basic process that can be observed even for key-pressing responses in a stimulus-response paradigm. In Ziessler, Nattkemper and Vogt’s (2012 experiments participants first learned arbitrary effects of key-pressing responses. In the test phase an imperative stimulus determined the response, but participants withheld the response until a Go-stimulus appeared. Reaction times were shorter if the Go-stimulus was compatible with the learned response effect. This is strong evidence that effect representations were activated during response planning. Here we repeated the experiment using event-related potentials (ERPs, and we found that Go-stimulus locked ERPs depended on the compatibility relationship between the Go-stimulus and the response effect. In general, this supports the interpretation of the behavioural data. More specifically, differences in the ERPs between compatible and incompatible Go-stimuli were found for the early perceptual P1 component and the later frontal P2 component. P1 differences were found only in the second half of the experiment and for long SOAs between imperative stimulus and Go-stimulus, i.e. when the effect was fully anticipated and the perceptual system was prepared for the effect-compatible Go-stimulus. P2 amplitudes, likely associated with evaluation and conflict detection, were larger when Go-stimulus and effect were incompatible; presumably, incompatibility increased the difficulty of effect anticipation. Onset of response-locked LRPs occurred earlier under incompatible conditions indicating extended motor processing. Together, these results strongly suggest that effect anticipation affects all (i.e. perceptual, cognitive, and motor phases of response preparation.

  17. Response inhibition is linked to emotional devaluation: behavioural and electrophysiological evidence

    Directory of Open Access Journals (Sweden)

    2008-10-01

    Full Text Available To study links between the inhibition of motor responses and emotional evaluation, we combined electrophysiological measures of prefrontal response inhibition with behavioural measures of affective evaluation. Participants first performed a Go-Nogo task in response to Asian and Caucasian faces (with race determining their Go or Nogo status, followed by a trustworthiness rating for each face. Faces previously seen as Nogo stimuli were rated as less trustworthy than previous Go stimuli. To study links between the efficiency of response inhibition in the Go-Nogo task and subsequent emotional evaluations, the Nogo N2 component was quantified separately for faces that were later judged to be high versus low in trustworthiness. Nogo N2 amplitudes were larger in response to low-rated as compared to high-rated faces, demonstrating that trial-by-trial variations in the efficiency of response inhibition triggered by Nogo faces, as measured by the Nogo N2 component, co-vary with their subsequent affective evaluation. These results suggest close links between inhibitory processes in top-down motor control and emotional responses.

  18. Using biomarkers to predict treatment response in major depressive disorder: evidence from past and present studies.

    Science.gov (United States)

    Thase, Michael E

    2014-12-01

    Major depressive disorder (MDD) is a heterogeneous condition with a variable response to a wide range of treatments. Despite intensive efforts, no biomarker has been identified to date that can reliably predict response or non-response to any form of treatment, nor has one been identified that can be used to identify those at high risk of developing treatment-resistant depression (ie, non-response to a sequence of treatments delivered for adequate duration and intensity). This manuscript reviews some past areas of research that have proved informative, such as studies using indexes of hypercortisolism or sleep disturbance, and more recent research findings using measures of inflammation and different indicators of regional cortical activation to predict treatment response. It is concluded that, although no method has yet been demonstrated to be sufficiently accurate to be applied in clinical practice, progress has been made. It thus seems likely that--at some point in the not-too-distant future--it will be possible to prospectively identify, at least for some MDD patients, the likelihood of response or non-response to cognitive therapy or various antidepressant medications.

  19. How Do Parameters of Motor Response Influence Selective Inhibition? Evidence from the Stop-Signal Paradigm

    Directory of Open Access Journals (Sweden)

    Chien Hui Tang

    2011-05-01

    Full Text Available The ability to selectively inhibit the execution of an action while performing other ones is crucial in humans' multitasking daily life. The current study aims to compare selective inhibition for choice reaction involving two effectors or response directions. We adopted a variation of the stop-signal paradigm to examine how selective inhibition is modulated by the way potential motor responses are combined and inhibited. Experiment 1 investigated selective inhibition under different combinations of effectors, namely “index and middle fingers” versus “hand and foot”. The results showed SSRT of the index finger was longer when the other response option was the foot than the middle finger. Experiment 2 examined how selective inhibition differs between selective stopping of effectors and movement directions, and that for most of the situations SSRT is longer for stopping a response based on its direction than effector. After equating complexity of response mapping between direction and effector conditions in Experiment 2, Experiment 3 still showed that SSRT differs between selecting direction or effectors. To summarize, SSRT varies depending on the way response effectors are paired and selectively stopped. Selective inhibition is thus likely not amodal and may involve different inhibitory mechanisms depending on parameters specifying the motor response.

  20. The immune response of bovine mammary epithelial cells to live or heat-inactivated Mycoplasma bovis.

    Science.gov (United States)

    Zbinden, Christina; Pilo, Paola; Frey, Joachim; Bruckmaier, Rupert M; Wellnitz, Olga

    2015-09-30

    Mycoplasma bovis is an emerging bacterial agent causing bovine mastitis. Although these cell wall-free bacteria lack classical virulence factors, they are able to activate the immune system of the host. However, effects on the bovine mammary immune system are not yet well characterized and detailed knowledge would improve the prevention and therapy of mycoplasmal mastitis. The aim of this study was to investigate the immunogenic effects of M. bovis on the mammary gland in an established primary bovine mammary epithelial cell (bMEC) culture system. Primary bMEC of four different cows were challenged with live and heat-inactivated M. bovis strain JF4278 isolated from acute bovine mastitis, as well as with the type strain PG45. The immune response was evaluated 6 and 24h after mycoplasmal challenge by measuring the relative mRNA expression of selected immune factors by quantitative PCR. M. bovis triggered an immune response in bMEC, reflected by the upregulation of tumor necrosis factor-α, interleukin(IL)-1β, IL-6, IL-8, lactoferrin, Toll-like receptor-2, RANTES, and serum amyloid A mRNA. Interestingly, this cellular reaction was only observed in response to live, but not to heat-inactivated M. bovis, in contrast to other bacterial pathogens of mastitis such as Staphylococcus aureus. This study provides evidence that bMEC exhibit a strong inflammatory reaction in response to live M. bovis. The lack of a cellular response to heat-inactivated M. bovis supports the current hypothesis that mycoplasmas activate the immune system through secreted secondary metabolites.

  1. Targeting the cell stress response of Plasmodium falciparum to overcome artemisinin resistance.

    Science.gov (United States)

    Dogovski, Con; Xie, Stanley C; Burgio, Gaetan; Bridgford, Jess; Mok, Sachel; McCaw, James M; Chotivanich, Kesinee; Kenny, Shannon; Gnädig, Nina; Straimer, Judith; Bozdech, Zbynek; Fidock, David A; Simpson, Julie A; Dondorp, Arjen M; Foote, Simon; Klonis, Nectarios; Tilley, Leann

    2015-04-01

    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 with ART

  2. Effect of 5-azacytidine: evidence for alteration of the multipotent ability of mesenchymal stem cells.

    Science.gov (United States)

    Rosca, Ana-Maria; Burlacu, Alexandrina

    2011-07-01

    The treatment of cardiac diseases by cell therapy continues to be challenged by a limited supply of appropriate cells. Although stem cells can generate myocytes after local delivery into the heart, this is often accompanied by the generation of several other cell types as a consequence of environment-driven differentiation. One strategy for overcoming dysregulated differentiation is the pretreatment of stem cells with the demethylation agent 5-azacytidine. The effects of 5-azacytidine on various stem cell types vary from cardiomyogenic differentiation to failure of differentiation or from adipogenic and chondrogenic differentiation to uncontrollable expression of a variety of genes. The underlying mechanisms remain poorly understood, and the effect of 5-azacytidine on the multipotent capacity of stem cells has never been addressed. This study was designed to investigate the changes induced by 5-azacytidine in mesenchymal stem cells (MSC), with particular focus on multipotency maintenance and the capacity of 5-azacytidine to boost myogenic differentiation. Our results show that MSCs retained their multipotent capacity after one pulse with 5-azacytidine, whereas additional pulses resulted in a restricted differentiation potential with concomitant increased ability to accomplish chondrogenic commitment. The induction of cardiac differentiation of MSCs was not observed unless the transcriptional activation of several genes was induced by random hypomethylation. Nevertheless, 5-azacytidine treatment promoted cell response to subsequent stimuli and generation of myogenic differentiation under permissive environmental conditions. Therefore, we assume that one pulse with 5-azacytidine might similarly promote the subsequent cardiac differentiation of MSCs, but it is dependent on the finding of adequate conditions for myocardial differentiation.

  3. Clinical adjuvant combinations stimulate potent B-cell responses in vitro by activating dermal dendritic cells.

    Directory of Open Access Journals (Sweden)

    Katie Matthews

    Full Text Available CD14(+ dermal DCs (CD14(+ DDCs have a natural capacity to activate naïve B-cells. Targeting CD14(+ DDCs is therefore a rational approach for vaccination strategies aimed at improving humoral responses towards poorly immunogenic antigens, for example, HIV-1 envelope glycoproteins (Env. Here, we show that two clinically relevant TLR ligand combinations, Hiltonol plus Resiquimod and Glucopyranosyl lipid A plus Resiquimod, potently activate CD14(+ DDCs, as shown by enhanced expression of multiple cytokines (IL-6, IL-10, IL-12p40 and TNF-α. Furthermore, the responses of CD14(+ DDCs to these TLR ligands were not compromised by the presence of HIV-1 gp120, which can drive immunosuppressive effects in vitro and in vivo. The above TLR ligand pairs were better than the individual agents at boosting the inherent capacity of CD14(+ DDCs to induce naïve B-cells to proliferate and differentiate into CD27(+ CD38(+ B-cells that secrete high levels of immunoglobulins. CD14(+ DDCs stimulated by these TLR ligand combinations also promoted the differentiation of Th1 (IFN-γ-secreting, but not Th17, CD4(+ T-cells. These observations may help to identify adjuvant strategies aimed at inducing better antibody responses to vaccine antigens, including, but not limited to HIV-1 Env.

  4. Adult age differences in visual search from perception to response: Evidence from event-related potentials

    DEFF Research Database (Denmark)

    Wiegand, Iris

    Attentional changes play a major role in age-related behavioral slowing, however, the specific aspects of attention that contribute to this decrement are not clearly defined. To these aims, we combined response times with lateralized ERPs of younger and older adults during a visual compound search...... at multiple stages from perception to response. Furthermore, we explored the implicit influence of recently encountered information in terms of intertrial effects. ERPs could disentangle that, while automatic processes of perceptual-dimension priming and response priming across trials were preserved, older...

  5. Thyroiditis in T cell-depleted rats: suppression of the autoallergic response by reconstitution with normal lymphoid cells.

    Science.gov (United States)

    Penhale, W J; Irvine, W J; Inglis, J R; Farmer, A

    1976-07-01

    Qualititive, quantitative and functional differences were found in lymphoid cells of female thymectomized and irradiated (Tx-X) PVG/c strain rats as compared to normal females of the same strain. Tx-X rats were lymphopenic and had reduced numbers of cells within spleen and cervical lymph nodes, depressed transformation responses of peripheral blood lymphocytes to PHA and lower percentage killing of their spleen cells by anti-T-cell serum and complement. There was an increased percentage of immunoglobulin-bearing cells in the lymph nodes. Reconstitution of Tx-X rats by the intravenous route using syngeneic lymph node cells, spleen cells or thymocytes abrogated the autoimmune responses to thyroid components generally observed in this state. Lymph node and spleen cells, but not thymocytes, also prevented thyroid changes when given intraperitoneally. In contrast, bone marrow cells appeared to give enhanced responses. Quntitative studies showed that the relative proportions of the suppressor or autoregulatory cells in various lymphoid tissues were lymph node greater than spleen greater than thymus. Complete abrogation of the autoimmune responses was possible only when cells were administered within a short time of final dose of irradiation and moderate thyroid change was again seen if transfer was delayed for 14 days post-irradiation. At 28 days reconstitution had no influence on the development of the autoimmune responses. Preliminary characterization studies using an anti-T-cell serum and fractionation of lymph node cells on a linear Ficoll gradient suggested that autoregulatory cell is a large T cell.

  6. 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.

  7. Targeting of Ly9 (CD229) Disrupts Marginal Zone and B1 B Cell Homeostasis and Antibody Responses.

    Science.gov (United States)

    Cuenca, Marta; Romero, Xavier; Sintes, Jordi; Terhorst, Cox; Engel, Pablo

    2016-01-15

    Marginal zone (MZ) and B1 B cells have the capacity to respond to foreign Ags more rapidly than conventional B cells, providing early immune responses to blood-borne pathogens. Ly9 (CD229, SLAMF3), a member of the signaling lymphocytic activation molecule family receptors, has been implicated in the development and function of innate T lymphocytes. In this article, we provide evidence that in Ly9-deficient mice splenic transitional 1, MZ, and B1a B cells are markedly expanded, whereas development of B lymphocytes in bone marrow is unaltered. Consistent with an increased number of these B cell subsets, we detected elevated levels of IgG3 natural Abs and a striking increase of T-independent type II Abs after immunization with 2,4,6-trinitrophenyl-Ficoll in the serum of Ly9-deficient mice. The notion that Ly9 could be a negative regulator of innate-like B cell responses was supported by the observation that administering an mAb directed against Ly9 to wild-type mice selectively eliminated splenic MZ B cells and significantly reduced the numbers of B1 and transitional 1 B cells. In addition, Ly9 mAb dramatically diminished in vivo humoral responses and caused a selective downregulation of the CD19/CD21/CD81 complex on B cells and concomitantly an impaired B cell survival and activation in an Fc-independent manner. We conclude that altered signaling caused by the absence of Ly9 or induced by anti-Ly9 may negatively regulate development and function of innate-like B cells by modulating B cell activation thresholds. The results suggest that Ly9 could serve as a novel target for the treatment of B cell-related diseases.

  8. Leukocyte TLR5 deficiency inhibits atherosclerosis by reduced macrophage recruitment and defective T-cell responsiveness

    Science.gov (United States)

    Ellenbroek, Guilielmus H.J.M.; van Puijvelde, Gijs H.M.; Anas, Adam A.; Bot, Martine; Asbach, Miriam; Schoneveld, Arjan; van Santbrink, Peter J.; Foks, Amanda C.; Timmers, Leo; Doevendans, Pieter A.; Pasterkamp, Gerard; Hoefer, Imo E.; van der Poll, Tom; Kuiper, Johan; de Jager, Saskia C.A.

    2017-01-01

    Toll-like receptors (TLR) provide a critical link between innate and adaptive immunity, both important players in atherosclerosis. Since evidence for the role of TLR5 is lacking, we aimed to establish this in the immune axis of atherosclerosis. We assessed the effect of the TLR5-specific ligand Flagellin on macrophage maturation and T-cell polarisation. Next, we generated TLR5−/−LDLr−/− chimeras to study the effect of hematopoietic TLR5 deficiency on atherosclerosis formation. Flagellin stimulation did not influence wildtype or TLR5−/− macrophage maturation. Only in wildtype macrophages, Flagellin exposure increased MCP-1 and IL6 expression. Flagellin alone reduced T-helper 1 proliferation, which was completely overruled in the presence of T-cell receptor activation. In vivo, hematopoietic TLR5 deficiency attenuated atherosclerotic lesion formation by ≈25% (1030*103 ± 63*103 vs. 792*103 ± 61*103 μm2; p = 0.013) and decreased macrophage area (81.3 ± 12.0 vs. 44.2 ± 6.6 μm2; p = 0.011). In TLR5−/− chimeric mice, we observed lower IL6 plasma levels (36.4 ± 5.6 vs. 15.1 ± 2.2 pg/mL; p = 0.003), lower (activated) splenic CD4+ T-cell content (32.3 ± 2.1 vs. 21.0 ± 1.2%; p = 0.0018), accompanied by impaired T-cell proliferative responses. In conclusion, hematopoietic TLR5 deficiency inhibits atherosclerotic lesion formation by attenuated macrophage accumulation and defective T-cell responsiveness. PMID:28202909

  9. Rapid, Dynamic Activation of Müller Glial Stem Cell Responses in Zebrafish

    Science.gov (United States)

    Sifuentes, Christopher J.; Kim, Jung-Woong; Swaroop, Anand; Raymond, Pamela A.

    2016-01-01

    Purpose Zebrafish neurons regenerate from Müller glia following retinal lesions. Genes and signaling pathways important for retinal regeneration in zebrafish have been described, but our understanding of how Müller glial stem cell properties are regulated is incomplete. Mammalian Müller glia possess a latent neurogenic capacity that might be enhanced in regenerative therapies to treat degenerative retinal diseases. Methods To identify transcriptional changes associated with stem cell properties in zebrafish Müller glia, we performed a comparative transcriptome analysis from isolated cells at 8 and 16 hours following an acute photic lesion, prior to the asymmetric division that produces retinal progenitors. Results We report a rapid, dynamic response of zebrafish Müller glia, characterized by activation of pathways related to stress, nuclear factor–κB (NF-κB) signaling, cytokine signaling, immunity, prostaglandin metabolism, circadian rhythm, and pluripotency, and an initial repression of Wnt signaling. When we compared publicly available transcriptomes of isolated mouse Müller glia from two retinal degeneration models, we found that mouse Müller glia showed evidence of oxidative stress, variable responses associated with immune regulation, and repression of pathways associated with pluripotency, development, and proliferation. Conclusions Categories of biological processes/pathways activated following photoreceptor loss in regeneration-competent zebrafish Müller glia, which distinguished them from mouse Müller glia in retinal degeneration models, included cytokine signaling (notably NF-κB), prostaglandin E2 synthesis, expression of core clock genes, and pathways/metabolic states associated with pluripotency. These regulatory mechanisms are relatively unexplored as potential mediators of stem cell properties likely to be important in Müller glial cells for successful retinal regeneration. PMID:27699411

  10. Necdin modulates proliferative cell survival of human cells in response to radiation-induced genotoxic stress

    Directory of Open Access Journals (Sweden)

    Lafontaine Julie

    2012-06-01

    Full Text Available Abstract Background The finite replicative lifespan of cells, termed cellular senescence, has been proposed as a protective mechanism against the proliferation of oncogenically damaged cells, that fuel cancer. This concept is further supported by the induction of premature senescence, a process which is activated when an oncogene is expressed in normal primary cells as well as following intense genotoxic stresses. Thus, deregulation of genes that control this process, like the tumor suppressor p53, may contribute to promoting cancer by allowing cells to bypass senescence. A better understanding of the genes that contribute to the establishment of senescence is therefore warranted. Necdin interacts with p53 and is also a p53 target gene, although the importance of Necdin in the p53 response is not clearly understood. Methods In this study, we first investigated Necdin protein expression during replicative senescence and premature senescence induced by gamma irradiation and by the overexpression of oncogenic RasV12. Gain and loss of function experiments were used to evaluate the contribution of Necdin during the senescence process. Results Necdin expression declined during replicative aging of IMR90 primary human fibroblasts or following induction of premature senescence. Decrease in Necdin expression seemed to be a consequence of the establishment of senescence since the depletion of Necdin in human cells did not induce a senescence-like growth arrest nor a flat morphology or SA-β-galactosidase activity normally associated with senescence. Similarly, overexpression of Necdin did not affect the life span of IMR90 cells. However, we demonstrate that in normal human cells, Necdin expression mimicked the effect of p53 inactivation by increasing radioresistance. Conclusion This result suggests that Necdin potentially attenuate p53 signaling in response to genotoxic stress in human cells and supports similar results describing an inhibitory function

  11. Plant traits in response to raising groundwater levels in wetland restoration: evidence from three case studies

    NARCIS (Netherlands)

    Bodegom, van P.M.; Grootjans, A.P.; Sorrell, B.K.; Bekker, R.M.; Bakker, C.; Ozinga, W.A.

    2006-01-01

    Question: Is raising groundwater tables successful as a wetland restoration strategy? Location: Kennemer dunes, The Netherlands; Moksloot dunes, The Netherlands and Bullock Creek fen, New Zealand. Methods: Generalizations were made by analysing soil dynamics and the responsiveness of integrative pla

  12. Plant traits in response to raising groundwater levels in wetland restoration : evidence from three case studies

    NARCIS (Netherlands)

    Bodegom, P.M. van; Grootjans, A.P.; Sorrell, B.K.; Bekker, R.M.; Bakker, C.; Ozinga, W.A.; Middleton, B.

    2006-01-01

    Question: Is raising groundwater tables successful as a wetland restoration strategy? Location: Kennemer dunes, The Netherlands; Moksloot dunes, The Netherlands and Bullock Creek fen, New Zealand. Methods: Generalizations were made by analysing soil dynamics and the responsiveness of integrative pla

  13. Two distinct functional patterns of hepatitis C Virus (HCV-specific T cell responses in seronegative, aviremic patients.

    Directory of Open Access Journals (Sweden)

    Yoon Seok Choi

    Full Text Available In hepatitis C Virus (HCV high-risk groups, HCV-specific T cell responses have been detected in seronegative, aviremic persons who have no evidence of HCV infection. Herein, we investigated functional profiles of HCV-specific T-cell responses in seronegative, aviremic patients of a HCV high-risk group. Seventy seven hemodialysis patients with chronic renal disease were analyzed by IFN-γ ELISpot assays, and eight of 71 (11.3% seronegative, aviremic patients displayed HCV-specific T-cell responses. Their HCV-specific memory T cells were characterized by assessing cytokine polyfunctionality, known to provide antiviral protection. By intracellular staining of IFN-γ, TNF-α, IL-2 and MIP-1β, we identified two distinct populations in the seronegative, aviremic patients: polyfunctional responders and TNF-α-predominant responders. In further analysis, occult HCV infection was excluded as a cause of the HCV-specific T cell response via secondary nested RT-PCR of HCV RNA in peripheral blood mononuclear cell samples. HCV-specific T cells targeted multiple epitopes including non-structural proteins in a single patient, implying that their T cells might have been primed by HCV proteins synthesized within the host. We conclude that HCV-specific memory T cells of seronegative, aviremic patients arise from authentic HCV replication in the host, but not from current occult HCV infection. By functional pattern of HCV-specific T cells, there are two distinct populations in these patients: polyfunctional responders and TNF-α-predominant responders.

  14. Disclosure and the Cost of Capital: Evidence from Firms' Responses to the Enron Shock

    OpenAIRE

    Christian Leuz; Catherine Schrand

    2009-01-01

    This paper examines the link between disclosure and the cost of capital. We exploit an exogenous cost of capital shock created by the Enron scandal in Fall 2001 and analyze firms' disclosure responses to this shock. These tests are opposite to the typical research design that analyzes cost of capital responses to disclosure changes. In reversing the tests and using an exogenous shock, we mitigate concerns about omitted variables in traditional cross-sectional disclosure studies. We estimate s...

  15. Evidence for an Early Origin of Vernalization Responsiveness in Temperate Pooideae Grasses.

    Science.gov (United States)

    McKeown, Meghan; Schubert, Marian; Marcussen, Thomas; Fjellheim, Siri; Preston, Jill C

    2016-09-01

    The ability of plants to match their reproductive output with favorable environmental conditions has major consequences both for lifetime fitness and geographic patterns of diversity. In temperate ecosystems, some plant species have evolved the ability to use winter nonfreezing cold (vernalization) as a cue to ready them for spring flowering. However, it is unknown how important the evolution of vernalization responsiveness has been for the colonization and subsequent diversification of taxa within the northern and southern temperate zones. Grasses of subfamily Pooideae, including several important crops, such as wheat (Triticum aestivum), barley (Hordeum vulgare), and oats (Avena sativa), predominate in the northern temperate zone, and it is hypothesized that their radiation was facilitated by the early evolution of vernalization responsiveness. Predictions of this early origin hypothesis are that a response to vernalization is widespread within the subfamily and that the genetic basis of this trait is conserved. To test these predictions, we determined and reconstructed vernalization responsiveness across Pooideae and compared expression of wheat vernalization gene orthologs VERNALIZATION1 (VRN1) and VRN3 in phylogenetically representative taxa under cold and control conditions. Our results demonstrate that vernalization responsive Pooideae species are widespread, suggesting that this trait evolved early in the lineage and that at least part of the vernalization gene network is conserved throughout the subfamily. These results are consistent with the hypothesis that the evolution of vernalization responsiveness was important for the initial transition of Pooideae out of the tropics and into the temperate zone.

  16. Evidence for an Early Origin of Vernalization Responsiveness in Temperate Pooideae Grasses1[OPEN

    Science.gov (United States)

    McKeown, Meghan; Fjellheim, Siri

    2016-01-01

    The ability of plants to match their reproductive output with favorable environmental conditions has major consequences both for lifetime fitness and geographic patterns of diversity. In temperate ecosystems, some plant species have evolved the ability to use winter nonfreezing cold (vernalization) as a cue to ready them for spring flowering. However, it is unknown how important the evolution of vernalization responsiveness has been for the colonization and subsequent diversification of taxa within the northern and southern temperate zones. Grasses of subfamily Pooideae, including several important crops, such as wheat (Triticum aestivum), barley (Hordeum vulgare), and oats (Avena sativa), predominate in the northern temperate zone, and it is hypothesized that their radiation was facilitated by the early evolution of vernalization responsiveness. Predictions of this early origin hypothesis are that a response to vernalization is widespread within the subfamily and that the genetic basis of this trait is conserved. To test these predictions, we determined and reconstructed vernalization responsiveness across Pooideae and compared expression of wheat vernalization gene orthologs VERNALIZATION1 (VRN1) and VRN3 in phylogenetically representative taxa under cold and control conditions. Our results demonstrate that vernalization responsive Pooideae species are widespread, suggesting that this trait evolved early in the lineage and that at least part of the vernalization gene network is conserved throughout the subfamily. These results are consistent with the hypothesis that the evolution of vernalization responsiveness was important for the initial transition of Pooideae out of the tropics and into the temperate zone. PMID:27474116

  17. Nanoscale Properties of Neural Cell Prosthetic and Astrocyte Response

    Science.gov (United States)

    Flowers, D. A.; Ayres, V. M.; Delgado-Rivera, R.; Ahmed, I.; Meiners, S. A.

    2009-03-01

    Preliminary data from in-vivo investigations (rat model) suggest that a nanofiber prosthetic device of fibroblast growth factor-2 (FGF-2)-modified nanofibers can correctly guide regenerating axons across an injury gap with aligned functional recovery. Scanning Probe Recognition Microscopy (SPRM) with auto-tracking of individual nanofibers is used for investigation of the key nanoscale properties of the nanofiber prosthetic device for central nervous system tissue engineering and repair. The key properties under SPRM investigation include nanofiber stiffness and surface roughness, nanofiber curvature, nanofiber mesh density and porosity, and growth factor presentation and distribution. Each of these factors has been demonstrated to have global effects on cell morphology, function, proliferation, morphogenesis, migration, and differentiation. The effect of FGF-2 modification on the key nanoscale properties is investigated. Results from the nanofiber prosthetic properties investigations are correlated with astrocyte response to unmodified and FGF-2 modified scaffolds, using 2D planar substrates as a control.

  18. Surveillance, response systems, and evidence updates on emerging zoonoses: the role of one health

    Directory of Open Access Journals (Sweden)

    G. V. Asokan

    2013-12-01

    Full Text Available Globally, emerging zoonotic diseases are increasing. Existing surveillance systems for zoonoses have substantial gaps, especially in developing countries, and the systems in place in the developed world require improvements. Resources and updates on evidence-based practice (EBP for zoonoses are sparser in the veterinary literature as compared to the medical literature. Evidence updates for emerging zoonoses are either absent or rudimentary in both human and veterinary medicine. A ‘one-health’ concept, including a global signaling surveillance system for emerging zoonoses, will be essential for correct diagnoses, interventions, and public health strategies. An open access EBP platform supported by builders of EBP resources is urgently needed to counter emerging zoonoses.

  19. Nickel elicits a fast antioxidant response in Coffea arabica cells.

    Science.gov (United States)

    Gomes-Junior, R A; Moldes, C A; Delite, F S; Gratão, P L; Mazzafera, P; Lea, P J; Azevedo, R A

    2006-01-01

    The antioxidant responses of coffee (Coffea arabica L.) cell suspension cultures to nickel (Ni) were investigated. Ni was very rapidly accumulated in the cells and the accumulation could be directly correlated with the increase of NiCl(2) concentration in the medium. At 0.05 mM NiCl(2) growth was stimulated, but at 0.5 mM NiCl(2), the growth rate was reduced. An indication of alterations in the presence of reactive oxygen species was detected by an increase in lipid peroxidation at 0.5 mM NiCl(2). Catalase (CAT; EC 1.11.1.6), glutathione reductase (GR; EC 1.6.4.2), ascorbate peroxidase (APX; EC 1.11.1.11), guaiacol peroxidase (GOPX; EC 1.11.1.7) and superoxide dismutase (SOD; EC 1.15.1.1) activities were increased, particularly at earlier NiCl(2) exposure times and the activities were higher at 0.5 mM NiCl(2) for most of exposure times tested. Non-denaturing PAGE revealed one CAT isoenzyme, nine SOD isoenzymes and four GR isoenzymes. The SOD isoenzymes were differentially affected by NiCl(2) treatment and one GR isoenzyme was increased by NiCl(2). NiCl(2) at 0.05 mM did not induce lipid peroxidation and the main response appeared to be via the induction of SOD, CAT, GOPX and APX activities for the removal of the reactive oxygen species and through the induction of GR to ensure the availability of reduced glutathione.

  20. Evidence for sex differences in cardiovascular aging and adaptive responses to physical activity

    OpenAIRE

    Parker, Beth A.; Kalasky, Martha J.; Proctor, David N.

    2010-01-01

    There are considerable data addressing sex-related differences in cardiovascular system aging and disease risk/progression. Sex differences in cardiovascular aging are evident during resting conditions, exercise, and other acute physiological challenges (e.g., orthostasis). In conjunction with these sex-related differences—or perhaps even as an underlying cause—the impact of cardiorespiratory fitness and/or physical activity on the aging cardiovascular system also appears to be sex-specific. ...

  1. Evidence for a critical role of gene occlusion in cell fate restriction

    Institute of Scientific and Technical Information of China (English)

    Jedidiah Gaetz; Wei-Hua Yu; Andy Peng Xiang; Bruce T Lahn; Kayla L Clift; Croydon J Fernandes; Frank Fuxiang Mao; Jae Hyun Lee; Li Zhang; Samuel W Baker; Timothy J Looney; Kara M Foshay

    2012-01-01

    The progressive restriction of cell fate during lineage differentiation is a poorly understood phenomenon despite its ubiquity in multicellular organisms.We recently used a cell fusion assay to define a mode of epigenetic silencing that we termed "occlusion",wherein affected genes are silenced by cis-acting chromatin mechanisms irrespective of whether trans-acting transcriptional activators are present.We hypothesized that occlusion of lineage-inappropriate genes could contribute to cell fate restriction.Here,we test this hypothesis by introducing bacterial artificial chromosomes (BACs),which are devoid of chromatin modifications necessary for occlusion,into mouse fibroblasts.We found that BAC transgenes corresponding to occluded endogenous genes are expressed in most eases,whereas BAC transgenes corresponding to silent but non-occluded endogenous genes are not expressed.This indicates that the cellular milieu in trans supports the expression of most occluded genes in fibroblasts,and that the silent state of these genes is solely the consequence of occlusion in cis.For the BAC corresponding to the occluded myogenic master regulator Myf5,expression of the Myf5 transgene on the BAC triggered fibroblasts to acquire a muscle-like phenotype.These results provide compelling evidence for a critical role of gene occlusion in cell fate restriction.

  2. Characterization of the specific CD4+ T cell response against the F protein during chronic hepatitis C virus infection.

    Directory of Open Access Journals (Sweden)

    De-Yong Gao

    Full Text Available BACKGROUND: The hepatitis C virus (HCV Alternate Reading Frame Protein (ARFP or F protein presents a double-frame shift product of the HCV core gene. We and others have previously reported that the specific antibodies against the F protein could be raised in the sera of HCV chronically infected patients. However, the specific CD4(+ T cell responses against the F protein during HCV infection and the pathological implications remained unclear. In the current study, we screened the MHC class II-presenting epitopes of the F protein through HLA-transgenic mouse models and eventually validated the specific CD4(+ T cell responses in HCV chronically infected patients. METHODOLOGY: DNA vaccination in HLA-DR1 and-DP4 transgenic mouse models, proliferation assay to test the F protein specific T cell response, genotyping of Chronic HCV patients and testing the F-peptide stimulated T cell response in the peripheral blood mononuclear cell (PBMC by in vitro expansion and interferon (IFN- γ intracellular staining. PRINCIPAL FINDINGS: At least three peptides within HCV F protein were identified as HLA-DR or HLA-DP4 presenting epitopes by the proliferation assays in mouse models. Further study with human PBMCs evidenced the specific CD4(+ T cell responses against HCV F protein as well in patients chronically infected with HCV. CONCLUSION: The current study provided the evidence for the first time that HCV F protein could elicit specific CD4(+ T cell response, which may provide an insight into the immunopathogenesis during HCV chronic infection.

  3. Evidence for toxicity differences between inorganic arsenite and thioarsenicals in human bladder cancer cells.

    Science.gov (United States)

    Naranmandura, Hua; Ogra, Yasumitsu; Iwata, Katsuya; Lee, Jane; Suzuki, Kazuo T; Weinfeld, Michael; Le, X Chris

    2009-07-15

    Arsenic toxicity is dependent on its chemical species. In humans, the bladder is one of the primary target organs for arsenic-induced carcinogenicity. However, little is known about the mechanisms underlying arsenic-induced carcinogenicity, and what arsenic species are responsible for this carcinogenicity. The present study aimed at comparing the toxic effect of DMMTA(V) with that of inorganic arsenite (iAs(III)) on cell viability, uptake efficiency and production of reactive oxygen species (ROS) toward human bladder cancer EJ-1 cells. The results were compared with those of a previous study using human epidermoid carcinoma A431 cells. Although iAs(III) was known to be toxic to most cells, here we show that iAs(III) (LC(50)=112 microM) was much less cytotoxic than DMMTA(V) (LC(50)=16.7 microM) in human bladder EJ-1 cells. Interestingly, pentavalent sulfur-containing DMMTA(V) generated a high level of intracellular ROS in EJ-1 cells. However, this was not observed in the cells exposed to trivalent inorganic iAs(III) at their respective LC(50) dose. Furthermore, the presence of N-acetyl-cysteine completely inhibited the cytotoxicity of DMMTA(V) but not iAs(III), suggesting that production of ROS was the main cause of cell death from exposure to DMMTA(V), but not iAs(III). Because the cellular uptake of iAs(III) is mediated by aquaporin proteins, and because the resistance of cells to arsenite can be influenced by lower arsenic uptake due to lower expression of aquaporin proteins (AQP 3, 7 and 9), the expression of several members of the aquaporin family was also examined. In human bladder EJ-1 cells, mRNA/proteins of AQP3, 7 and 9 were not detected by reverse transcription polymerase chain reaction (RT-PCR)/western blotting. In A431 cells, only mRNA and protein of AQP3 were detected. The large difference in toxicity between the two cell lines could be related to their differences in uptake of arsenic species.

  4. Evidence of human papilloma virus infection and its epidemiology in esophageal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    Pin-Fang Yao; Ju-Wei Sha; Guang-Can Li; Jin Li; He-Shun Xia; Xiao-Ling Yang; Huan-Yuan Huang; You-Gao Fu; Rui-Qin Wang; Xi-Yin Wang

    2006-01-01

    AIM: To look for the evidence of human papilloma virus (HPV) infection in esophageal squamous cell carcinomas (ESCC) and to investigate the potential role and epidemiology of HPV infection in the pathogenesis of esophageal carcinomas in Henan emigrants.METHODS: Papilloma virus (PV) and HPV were determined by UltrasensiveTM S-P immunohistochemistry (IHC)and in situ hybridization (ISH) in esophageal carcinoma tissues (82.cases) and the normal mucosa (40 cases).RESULTS: IHC revealed that the positive rate of PV was 75.0%, 68.18% and 72.5% respectively while the HPV (16/18-E6) positive rate was 45.0%, 36.36%, 37.5%,respectively in esophageal carcinoma tissue specimens from Henan emigrants,the local citizens and patients in Hubei Cancer Hospital. The PV and HPV (16/18-E6) were negative in all normal esophageal mucosa specimens. No correlation was found between HPV in esophageal squamous cell carcinoma tissues and in grade 1-3 esophageal squamous cell carcinoma cells. In situ hybridization showed that the HPV (16/18) DNA positive rate was 30.0%, 31.8%, 25.0%, respectively in the 3 groups of samples. No positive hybridization signal was found in 40 normal esophageal mucosa specimens. The positive rate of HPV (16/18) DNA in the esophageal carcinoma specimens was significantly higher than that in normal mucosa specimens (P< 0.05). The positive rate was not different among the 3 groups of esophageal carcinoma tissue specimens (P>0.05).CONCLUSION: HPV infection is high in esophageal carcinoma of Henan emigrants, local residents and patients in Hubei Cancer Hospital. HPV is closely related with esophageal squamous cell carcinoma. HPV infection may play an important role in esophageal squamous cell carcinoma.

  5. A novel single-cell method provides direct evidence of persistent DNA damage in senescent cells and aged mammalian tissues.

    Science.gov (United States)

    Galbiati, Alessandro; Beauséjour, Christian; d'Adda di Fagagna, Fabrizio

    2017-01-26

    The DNA damage response (DDR) arrests cell cycle progression until DNA lesions, like DNA double-strand breaks (DSBs), are repaired. The presence of DSBs in cells is usually detected by indirect techniques that rely on the accumulation of proteins at DSBs, as part of the DDR. Such detection may be biased, as some factors and their modifications may not reflect physical DNA damage. The dependency on DDR markers of DSB detection tools has left questions unanswered. In particular, it is known that senescent cells display persistent DDR foci, that we and others have proposed to be persistent DSBs, resistant to endogenous DNA repair activities. Others have proposed that these peculiar DDR foci might not be sites of damaged DNA per se but instead stable chromatin modifications, termed DNA-SCARS. Here, we developed a method, named 'DNA damage in situ ligation followed by proximity ligation assay' (DI-PLA) for the detection and imaging of DSBs in cells. DI-PLA is based on the capture of free DNA ends in fixed cells in situ, by ligation to biotinylated double-stranded DNA oligonucleotides, which are next recognized by antibiotin anti-bodies. Detection is enhanced by PLA with a partner DDR marker at the DSB. We validated DI-PLA by demonstrating its ability to detect DSBs induced by various genotoxic insults in cultured cells and tissues. Most importantly, by DI-PLA, we demonstrated that both senescent cells in culture and tissues from aged mammals retain true unrepaired DSBs associated with DDR markers.

  6. Emotional responses to irony and emoticons in written language: Evidence from EDA and facial EMG.

    Science.gov (United States)

    Thompson, Dominic; Mackenzie, Ian G; Leuthold, Hartmut; Filik, Ruth

    2016-07-01

    While the basic nature of irony is saying one thing and communicating the opposite, it may also serve additional social and emotional functions, such as projecting humor or anger. Emoticons often accompany irony in computer-mediated communication, and have been suggested to increase enjoyment of communication. In the current study, we aimed to examine online emotional responses to ironic versus literal comments, and the influence of emoticons on this process. Participants read stories with a final comment that was either ironic or literal, praising or critical, and with or without an emoticon. We used psychophysiological measures to capture immediate emotional responses: electrodermal activity to directly measure arousal and facial electromyography to detect muscle movements indicative of emotional expressions. Results showed higher arousal, reduced frowning, and enhanced smiling for messages with rather than without an emoticon, suggesting that emoticons increase positive emotions. A tendency toward less negative responses (i.e., reduced frowning and enhanced smiling) for ironic than literal criticism, and less positive responses (i.e., enhanced frowning and reduced smiling) for ironic than literal praise suggests that irony weakens the emotional impact of a message. The present findings indicate the utility of a psychophysiological approach in studying online emotional responses to written language.

  7. Short communication: Initial evidence supporting existence of potential rumen epidermal stem and progenitor cells.

    Science.gov (United States)

    Yohe, T T; Tucker, H L M; Parsons, C L M; Geiger, A J; Akers, R M; Daniels, K M

    2016-09-01

    The bovine rumen epidermis is a keratinized multilayered tissue that experiences persistent cell turnover. Because of this constant cell turnover, epidermal stem cells and their slightly more differentiated daughter cells, epidermal progenitor cells, must exist in the stratum basale of rumen epidermis. To date, these 2 epidermal cell populations and any unique cellular markers they may possess remain completely uncharacterized in the bovine rumen. An important first step in this new research area is the demonstration of the relative abundance and existence of markers for these cells in rumen tissue. A related second step is to document rumen epidermal proliferative responses to an extrinsic signal such as nutrient concentration within the rumen. The objectives of this experiment were to evaluate the extrinsic effect of diet on (1) gene expression of 6 potential rumen epidermal stem or progenitor cell markers and (2) rumen epidermal cell proliferation within the stratum basale. Twelve preweaned Holstein heifers were fed either a restricted diet (R) or an enhanced diet (EH). Animals on R received a milk replacer (MR) diet fed at 0.44kg of powder dry matter (DM)/d (20.9% crude protein, 29.8% fat, DM basis) and EH received MR at 1.08kg of powder dry matter/d (28.9% crude protein, 26.2% fat, DM basis). All calves had access to a 20% crude protein starter and were weaned during wk 7 of the experiment. Lifetime DM intake was 0.73kg of DM/calf per day for R (5.88 Mcal of net energy/calf per day) and 1.26kg of DM/calf per day for EH (10.68 Mcal of net energy/calf per day). Twenty-four hours before slaughter heifers received an intravenous dose of 5-bromo-2'-deoxyuridine to label proliferating cells. Heifers were slaughtered at 8 wk of age, and rumen samples from the ventral sac region were obtained and stored in RNA preservative and processed for routine histology. Quantitative real-time reverse transcriptase PCR was used to analyze relative abundance of genes. Candidate

  8. 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.

  9. Activation of vitamin D regulates response of human bronchial epithelial cells to Aspergillus fumigatus in an autocrine fashion.

    Science.gov (United States)

    Li, Pei; Wu, Ting; Su, Xin; Shi, Yi

    2015-01-01

    Aspergillus fumigatus (A. fumigatus) is one of the most common fungi to cause diseases in humans. Recent evidence has demonstrated that airway epithelial cells play an important role in combating A. fumigatus through inflammatory responses. Human airway epithelial cells have been proven to synthesize the active vitamin D, which plays a key role in regulating inflammation. The present study was conducted to investigate the impact of A. fumigatus infection on the activation of vitamin D and the role of vitamin D activation in A. fumigatus-elicited antifungal immunity in normal human airway epithelial cells. We found that A. fumigatus swollen conidia (SC) induced the expression of 1α-hydroxylase, the enzyme catalyzing the synthesis of active vitamin D, and vitamin D receptor (VDR) in 16HBE cells and led to increased local generation of active vitamin D. Locally activated vitamin D amplified SC-induced expression of antimicrobial peptides in 16HBE cells but attenuated SC-induced production of cytokines in an autocrine fashion. Furthermore, we identified β-glucan, the major A. fumigatus cell wall component, as the causative agent for upregulation of 1α-hydroxylase and VDR in 16HBE cells. Therefore, activation of vitamin D is inducible and provides a bidirectional regulation of the responses to A. fumigatus in 16HBE cells.

  10. Timing of CD8+ T cell responses in relation to commencement of capillary leakage in children with dengue.

    Science.gov (United States)

    Dung, Nguyen Thi Phuong; Duyen, Huynh Thi Le; Thuy, Nguyen Thi Van; Ngoc, Tran Van; Chau, Nguyen Van Vinh; Hien, Tran Tinh; Rowland-Jones, Sarah L; Dong, Tao; Farrar, Jeremy; Wills, Bridget; Simmons, Cameron P

    2010-06-15

    Immune activation is a feature of dengue hemorrhagic fever (DHF) and CD8+ T cell responses in particular have been suggested as having a role in the vasculopathy that characterizes this disease. By phenotyping CD8+ T cells (CD38+/HLA-DR+, CD38+/Ki-67+, or HLA-DR+/Ki-67+) in serial blood samples from children with dengue, we found no evidence of increased CD8+ T cell activation prior to the commencement of resolution of viremia or hemoconcentration. Investigations with MHC class I tetramers to detect NS3(133-142)-specific CD8+ T cells in two independent cohorts of children suggested the commencement of hemoconcentration and thrombocytopenia in DHF patients generally begins before the appearance of measurable frequencies of NS3(133-142)-specific CD8+ T cells. The temporal mismatch between the appearance of measurable surface activated or NS3(133-142)-specific CD8+ T cells suggests that these cells are sequestered at sites of infection, have phenotypes not detected by our approach, or that other mechanisms independent of CD8+ T cells are responsible for early triggering of capillary leakage in children with DHF.

  11. Bilingualism increases neural response consistency and attentional control: evidence for sensory and cognitive coupling.

    Science.gov (United States)

    Krizman, Jennifer; Skoe, Erika; Marian, Viorica; Kraus, Nina

    2014-01-01

    Auditory processing is presumed to be influenced by cognitive processes - including attentional control - in a top-down manner. In bilinguals, activation of both languages during daily communication hones inhibitory skills, which subsequently bolster attentional control. We hypothesize that the heightened attentional demands of bilingual communication strengthens connections between cognitive (i.e., attentional control) and auditory processing, leading to greater across-trial consistency in the auditory evoked response (i.e., neural consistency) in bilinguals. To assess this, we collected passively-elicited auditory evoked responses to the syllable [da] in adolescent Spanish-English bilinguals and English monolinguals and separately obtained measures of attentional control and language ability. Bilinguals demonstrated enhanced attentional control and more consistent brainstem and cortical responses. In bilinguals, but not monolinguals, brainstem consistency tracked with language proficiency and attentional control. We interpret these enhancements in neural consistency as the outcome of strengthened attentional control that emerged from experience communicating in two languages.

  12. 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

  13. Lipoproteins are Major Targets of the Polyclonal Human T-cell Response to M. tuberculosis1

    OpenAIRE

    2012-01-01

    Most vaccines and basic studies of T cell epitopes in M. tuberculosis emphasize water soluble proteins that are secreted into the extracellular space and presented in the context of MHC Class II. Much less is known about the role of antigens retained within the cell wall. We used polyclonal T cells from infected humans to probe for responses to immunodominant antigens in the M. tuberculosis cell wall. We found that the magnitude of response to secreted or cell wall intrinsic compounds was sim...

  14. Mathematical modeling of the specific T cell response to a viral infection

    OpenAIRE

    Bidot, Caroline

    2006-01-01

    T cell is one of the most important cells in specific immunity. In order to devise a tool for understanding and predicting some mechanisms of the immune system, a model for T cell response is proposed. The T lymphocyte activation by the recognition of a peptide carried by an antigen presenting cell is an essential step of this immune response. T cell activation was modelled by a system of ordinary differential equations of chemical kinetics type, representing the temporal evolution of the con...

  15. The social welfare function and individual responsibility: some theoretical issues and empirical evidence.

    Science.gov (United States)

    Dolan, Paul; Tsuchiya, Aki

    2009-01-01

    The literature on income distribution has attempted to evaluate different degrees of inequality using a social welfare function (SWF) approach. However, it has largely ignored the source of such inequalities, and has thus failed to consider different degrees of inequity. The literature on egalitarianism has addressed issues of equity, largely in relation to individual responsibility. This paper builds upon these two literatures, and introduces individual responsibility into the SWF. Results from a small-scale study of people's preferences in relation to the distribution of health benefits are presented to illustrate how the parameter values of a SWF might be determined.

  16. Heteroclitic Peptides Increase Proliferation and Reduce Evidence of Human Immunodeficiency Virus-Specific CD8⁺ T Cell Dysfunction.

    Science.gov (United States)

    Adegoke, Adeolu; Gladney, Krista; Gallant, Maureen; Grant, Michael

    2015-10-01

    Human immunodeficiency virus (HIV)-specific CD8(+) T cell dysfunction parallels disease progression; therefore, restoring potent HIV-specific CD8(+) T cell responses is a key therapeutic goal. Certain CD8(+) T cell peptide epitope variants, termed heteroclitic, enhance cytokine production by the HIV-specific CD8(+) T cells of some individuals. In this study, we investigated whether heteroclitic peptides that enhance cytokine production by HIV-specific CD8(+) T cells also reduce functional and phenotypic evidence of HIV-specific CD8(+) T cell exhaustion in those instances. Twenty-four variant peptides of human histocompatibility-linked leukocyte antigen (HLA)-A2-restricted reference HIV peptide epitopes designated as A2-7; Nef 83→91, A2-8; Nef 135→143, A2-Gag; Gag 77→85 and A2-9; Gag 433→440 were synthesized with conservative and semiconservative amino acid substitutions at positions 3, 5, and 7 or 3, 5, and 8 of Gag 433→440. Variants that enhanced interferon-gamma (IFN-γ) and/or interleukin-2 (IL-2) production in enzyme-linked immunospot assays (29 cases overall) were subsequently tested by 7-day in vitro peptide stimulation for their effects on HIV-specific CD8(+) T cell proliferation and programmed death-1 (PD-1) expression. Heteroclitic variants enhanced HIV-specific CD8(+) T cell proliferation by >20% in 13/29 cases tested, reduced PD-1 expression on proliferating cells by 15-50% in 10 cases, and reduced PD-1 expression on proliferating cells by >50% in 3 cases. In five cases, the same heteroclitic peptide increased proliferation by >20% and reduced PD-1 expression by >15%. These data demonstrate that heteroclitic peptides can alter the magnitude and character of HIV-specific CD8(+) cell responses relative to reference peptides and may have a unique immunotherapeutic value in therapeutic vaccines.

  17. 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.

  18. 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.

  19. Studies of cell-mediated immune responses to influenza vaccination in systemic lupus erythematosus

    NARCIS (Netherlands)

    Holvast, Albert; Van Assen, Sander; De Haan, Aalzen; Huckriede, Anke; Benne, Cornelis A.; Westra, Johanna; Palache, Abraham; Wilschut, Jan; Kallenberg, Cornelis; Bijl, Marc

    2009-01-01

    Objective. Both antibody and cell-mediated responses are involved in the defense against influenza. In patients with systemic lupus erythematosus (SLE), a decreased antibody response to subunit influenza vaccine has been demonstrated, but cell-mediated responses have not yet been assessed. This stud

  20. 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.

  1. A temperature-responsive network links cell shape and virulence traits in a primary fungal pathogen.

    Directory of Open Access Journals (Sweden)

    Sinem Beyhan

    2013-07-01

    Full Text Available Survival at host temperature is a critical trait for pathogenic microbes of humans. Thermally dimorphic fungal pathogens, including Histoplasma capsulatum, are soil fungi that undergo dramatic changes in cell shape and virulence gene expression in response to host temperature. How these organisms link changes in temperature to both morphologic development and expression of virulence traits is unknown. Here we elucidate a temperature-responsive transcriptional network in H. capsulatum, which switches from a filamentous form in the environment to a pathogenic yeast form at body temperature. The circuit is driven by three highly conserved factors, Ryp1, Ryp2, and Ryp3, that are required for yeast-phase growth at 37°C. Ryp factors belong to distinct families of proteins that control developmental transitions in fungi: Ryp1 is a member of the WOPR family of transcription factors, and Ryp2 and Ryp3 are both members of the Velvet family of proteins whose molecular function is unknown. Here we provide the first evidence that these WOPR and Velvet proteins interact, and that Velvet proteins associate with DNA to drive gene expression. Using genome-wide chromatin immunoprecipitation studies, we determine that Ryp1, Ryp2, and Ryp3 associate with a large common set of genomic loci that includes known virulence genes, indicating that the Ryp factors directly control genes required for pathogenicity in addition to their role in regulating cell morphology. We further dissect the Ryp regulatory circuit by determining that a fourth transcription factor, which we name Ryp4, is required for yeast-phase growth and gene expression, associates with DNA, and displays interdependent regulation with Ryp1, Ryp2, and Ryp3. Finally, we define cis-acting motifs that recruit the Ryp factors to their interwoven network of temperature-responsive target genes. Taken together, our results reveal a positive feedback circuit that directs a broad transcriptional switch between

  2. Purine and pyrimidine metabolism: Convergent evidence on chronic antidepressant treatment response in mice and humans

    Science.gov (United States)

    Park, Dong Ik; Dournes, Carine; Sillaber, Inge; Uhr, Manfred; Asara, John M.; Gassen, Nils C.; Rein, Theo; Ising, Marcus; Webhofer, Christian; Filiou, Michaela D.; Müller, Marianne B.; Turck, Christoph W.

    2016-01-01

    Selective Serotonin Reuptake Inhibitors (SSRIs) are commonly used drugs for the treatment of psychiatric diseases including major depressive disorder (MDD). For unknown reasons a substantial number of patients do not show any improvement during or after SSRI treatment. We treated DBA/2J mice for 28 days with paroxetine and assessed their behavioral response with the forced swim test (FST). Paroxetine-treated long-time floating (PLF) and paroxetine-treated short-time floating (PSF) groups were stratified as proxies for drug non-responder and responder mice, respectively. Proteomics and metabolomics profiles of PLF and PSF groups were acquired for the hippocampus and plasma to identify molecular pathways and biosignatures that stratify paroxetine-treated mouse sub-groups. The critical role of purine and pyrimidine metabolisms for chronic paroxetine treatment response in the mouse was further corroborated by pathway protein expression differences in both mice and patients that underwent chronic antidepressant treatment. The integrated -omics data indicate purine and pyrimidine metabolism pathway activity differences between PLF and PSF mice. Furthermore, the pathway protein levels in peripheral specimens strongly correlated with the antidepressant treatment response in patients. Our results suggest that chronic SSRI treatment differentially affects purine and pyrimidine metabolisms, which may explain the heterogeneous antidepressant treatment response and represents a potential biosignature. PMID:27731396

  3. Further neuroendocrine evidence of enhanced vasopressin V3 receptor responses in melancholic depression.

    LENUS (Irish Health Repository)

    Dinan, T G

    2012-02-03

    BACKGROUND: In situations of chronic stress vasopressin plays an important role in regulating the hypothalamic-pituitary adrenal axis. The aim of the current study was to investigate the role of anterior pituitary vasopressin V3 receptors in maintaining the hypercortisolism seen in melancholic depression. METHOD: Fourteen patients with major depression and 14 age- and sex-matched healthy comparison subjects were recruited. Desmopressin (ddAVP) 10 microg was given intravenously and ACTH and cortisol release was monitored for 120 min. RESULTS: The mean +\\/- S.E.M. ACTH response in the depressives was 28.4 +\\/- 4.3 ng\\/l and in the healthy subjects was 18.8 +\\/- 4.9 ng\\/l (P = 0.04). The mean +\\/- S.E.M. cortisol response in the depressives was 261.8 +\\/- 46.5 nmol\\/l and in the healthy subjects was 107.3 +\\/- 26.1 nmol\\/l (P < 0.01). CONCLUSIONS: Patients with major depression have augmented ACTH and cortisol responses to desmopressin indicating enhanced V3 responsivity.

  4. On the Interpretation of the Number Attraction Effect: Response Time Evidence

    Science.gov (United States)

    Staub, Adrian

    2009-01-01

    Speakers frequently make subject-verb number agreement errors in the presence of a local noun with a different number from the head of the subject phrase. A series of four experiments used a two-choice response time (RT) paradigm to investigate how the latency of correct agreement decisions is modulated by the presence of a number attractor, and…

  5. SIMILARITIES AND DIFFERENCES IN TEACHING CORPORATE SOCIAL RESPONSIBILITY: EVIDENCE FROM MEXICO AND CANADA

    Directory of Open Access Journals (Sweden)

    GONZALEZ, Santiago

    2016-09-01

    Full Text Available The need to incorporate and develop Corporate Social Responsibility (CSR within university programs is necessary for future leaders, managers and entrepreneurs. Within the framework of CSR and stakeholder theory the paper contributes a comparative case study that utilizes curriculum and in-depth interview analysis to illustrate not only the similarities and differences in the CSR programs, but how social responsibility is taught in a Mexican and Canadian University context. The main findings are: the CSR program in Mexico is perceived as a strategic management tool that adds value to the organization and does not pay any special attention to the globalization phenomena. Whereas in Canada, social responsibility is founded on ethics, attention to the different stakeholders in a globalized environment is emphasized and the strategic importance of CSR is widely accepted. The paper provides academics and researcher insight into exploring how universities can further facilitate students as stakeholders in considering social responsibility as important and necessary to ensure CSR sustainability in practice.

  6. PSYCHOPHYSIOLOGICAL EVIDENCE FOR CONTINUOUS INFORMATION-TRANSMISSION BETWEEN VISUAL-SEARCH AND RESPONSE PROCESSES

    NARCIS (Netherlands)

    SMID, HGOM; LAMAIN, W; HOGEBOOM, MM; Mulder, Lambertus; Mulder, Gysbertus