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Sample records for cells remains unclear

  1. Fate of nuclear waste site remains unclear

    International Nuclear Information System (INIS)

    Anderson, E.V.

    1980-01-01

    The only commercial nuclear fuel reprocessing plant in the U.S., located in West Valley, N.Y., has been shut down since 1972, and no efforts have yet been made to clean up the site. The site contains a spent-fuel pool, high level liquid waste storage tanks, and two radioactive waste burial grounds. Nuclear Fuel Services, Inc., has been leasing the site from the New York State Energy RandD Authority. Federal litigation may ensue, prompted by NRC and DOE, if the company refuses to decontaminate the area when its lease expires at the end of 1980. DOE has developed a plan to solidify the liquid wastes at the facility but needs additional legislation and funding to implement the scheme

  2. Unclear-onset intracerebral hemorrhage: Clinical characteristics, hematoma features, and outcomes.

    Science.gov (United States)

    Inoue, Yasuteru; Miyashita, Fumio; Koga, Masatoshi; Minematsu, Kazuo; Toyoda, Kazunori

    2017-12-01

    Background and purpose Although unclear-onset ischemic stroke, including wake-up ischemic stroke, is drawing attention as a potential target for reperfusion therapy, acute unclear-onset intracerebral hemorrhage has been understudied. Clinical characteristics, hematoma features, and outcomes of patients who developed intracerebral hemorrhage during sleep or those with intracerebral hemorrhage who were unconscious when witnessed were determined. Methods Consecutive intracerebral hemorrhage patients admitted within 24 hours after onset or last-known normal time were classified into clear-onset intracerebral hemorrhage and unclear-onset intracerebral hemorrhage groups. Outcomes included initial hematoma volume, initial National Institutes of Health Stroke Scale score, hematoma growth on 24-hour follow-up computed tomography, and vital and functional prognoses at 30 days. Results Of 377 studied patients (122 women, 69 ± 11 years old), 147 (39.0%) had unclear-onset intracerebral hemorrhage. Patients with unclear-onset intracerebral hemorrhage had larger hematoma volumes (p = 0.044) and higher National Institutes of Health Stroke Scale scores (p Hematoma growth was similarly common between the two groups (p = 0.176). There were fewer patients with modified Rankin Scale (mRS) scores of 0-2 (p = 0.033) and more patients with mRS scores of 5-6 (p = 0.009) and with fatal outcomes (p = 0.049) in unclear-onset intracerebral hemorrhage group compared with clear-onset intracerebral hemorrhage as crude values, but not after adjustment. Conclusions Patients with unclear-onset intracerebral hemorrhage presented with larger hematomas and higher National Institutes of Health Stroke Scale scores at emergent visits than those with clear-onset intracerebral hemorrhage, independent of underlying characteristics. Unclear-onset intracerebral hemorrhage patients showed poorer 30-day vital and functional outcomes than clear-onset intracerebral hemorrhage patients

  3. Quantum Dots for Cancer Research: Current Status, Remaining Issues, and Future Perspectives

    International Nuclear Information System (INIS)

    Fang, Min; Peng, Chun-wei; Pang, Dai-Wen; Li, Yan

    2012-01-01

    Cancer is a major threat to public health in the 21st century because it is one of the leading causes of death worldwide. The mechanisms of carcinogenesis, cancer invasion, and metastasis remain unclear. Thus, the development of a novel approach for cancer detection is urgent, and real-time monitoring is crucial in revealing its underlying biological mechanisms. With the optical and chemical advantages of quantum dots (QDs), QD-based nanotechnology is helpful in constructing a biomedical imaging platform for cancer behavior study. This review mainly focuses on the application of QD-based nanotechnology in cancer cell imaging and tumor microenvironment studies both in vivo and in vitro, as well as the remaining issues and future perspectives

  4. Treatment-related changes in serum lipids and inflammation: clinical relevance remains unclear. Analyses from the Women's Interagency HIV Study

    Science.gov (United States)

    Parrinello, Christina M; Landay, Alan L; Hodis, Howard N; Gange, Stephen J; Norris, Philip J; Young, Mary; Anastos, Kathryn; Tien, Phyllis C; Xue, Xiaonan; Lazar, Jason; Benning, Lorie; Tracy, Russell P; Kaplan, Robert C

    2014-01-01

    Summary Among 127 HIV-infected women, the magnitude of HDLc increases after HAART initiation predicted the magnitude of concurrent decreases in inflammation biomarkers. After HAART initiation, changes in LDLc and inflammation were unrelated. In the same population, predicted risk of coronary heart disease based upon levels of standard clinical risk factors was similar before and after HAART treatment. Thus, it remains unknown whether short-term treatment-related changes in standard risk factors may appreciably change risk of CVD. PMID:23435295

  5. Modeling cell-in-cell structure into its biological significance

    OpenAIRE

    He, M-f; Wang, S; Wang, Y; Wang, X-n

    2013-01-01

    Although cell-in-cell structure was noted 100 years ago, the molecular mechanisms of ?entering' and the destination of cell-in-cell remain largely unclear. It takes place among the same type of cells (homotypic cell-in-cell) or different types of cells (heterotypic cell-in-cell). Cell-in-cell formation affects both effector cells and their host cells in multiple aspects, while cell-in-cell death is under more intensive investigation. Given that cell-in-cell has an important role in maintainin...

  6. TOX sets the stage for innate lymphoid cells

    NARCIS (Netherlands)

    Spits, Hergen

    2015-01-01

    Like T cells and B cells, innate lymphoid cells (ILCs) develop from common lymphoid progenitors, but how commitment to the ILC lineage is regulated has remained unclear. The transcriptional regulator TOX is important in this process

  7. The Performance of Public Organization: Still Unclear

    Directory of Open Access Journals (Sweden)

    Bacanu B.

    2014-12-01

    Full Text Available Nowadays, the present discussions about the organisation’s performance have revealed the fact that the concept is unclear. The use of the concept is more difficult in public organisations. The paper presents the case of Romanian SOE Hidroelectrica and the case of public universities, to pinpoint the fact that ambiguous objectives are the cause of a dilemmatic management. The general opinion is that the results of the public organisations management reflect a poor performance of the latter.

  8. THE MODEL OF UNCLEAR EXPERT SYSTEM OF PROGNOSTICATION THE CONTENT OF EDUCATION

    Directory of Open Access Journals (Sweden)

    Ivan M. Tsidylo

    2012-12-01

    Full Text Available The article deals with the problem of development of the expert system of prognostication of the educational content by means of fuzzy logic. It was the model of making decision by the group of experts in accordance to meaningfulness of the theme in the educational programme on the base of the hierarchical system that combines in itself the use of both unclear and stochastic data. The structure of the unclear system, function and mechanisms of construction of separate blocks of the model are described. The surface of review of the unclear system represents dependence of estimation of the theme meaningfulness on the level of competence of group of experts and size to the point at the permanent value of level’s variation. The testing of the controller on a test selection proves the functional fitness of the developed model.

  9. Role of lymphoscintigraphy in diagnosis and management of patients with leg swelling of unclear etiology

    International Nuclear Information System (INIS)

    Kalawat, Tek Chand; Chittoria, Ravi Kumar; Reddy, Praveen Kumar; Suneetha, Batchu; Narayan, Ravishwar; Ravi, Parthsarthi

    2012-01-01

    To study the utility of lymphoscintigraphy in detection of lymphatic obstruction in patients with leg swelling of unclear etiology, selection of site for nodo venous shunt procedure, and follow-up lymphoscintigraphic documentation of improved lymph flow in surgically treated limb. Twenty four consecutive patients with leg swelling, 10 male, 14 female with mean age 47 years, range from 13 years to 74 years underwent lymphoscintigraphy. All patients were referred from Department of Plastic Surgery, after initial work-up, and routine investigations to rule out the other causes of leg swelling. Both clinical and scintigraphic staging performed for all patients. All clinically and scintigraphically positive patients treated with decongestive lymphatic therapy (DLT). In addition to the DLT, those patients positive for unilateral or bilateral lymphedema, consented for surgical intervention, nodo venous shunt (NVS) in their only affected or one of the two affected lower limbs. Follow-up lymphoscintigraphy performed in operated cases after 3 months to 6 months of surgery, lymphoscintigraphy images of each patient in pre and post-surgery compared. In 20/24 cases (83%) of clinically positive leg swelling were found to be positive for lymphedema on lymphoscintigraphy and remaining, 4/24 were scintigraphically normal. Based on the clinical and lymphoscintigraphy staging, 03/20 cases (15%) had Grade I lymphedema, 01/20 (5%) Grade II lymphedema, 06/20 (30%) Grade III and remaining 10/20 (50%) had Grade IV lymphedema. 11/20 cases of Lymphedema (55%) were managed conservatively by only DLT and in remaining 09/20 cases (45%), who were case of Grade IV, lymphedema (five patients with unilateral and four patients with bilateral disease) initially treated with DLT, and on completion of DLT, undergone for NVS procedure, in their unilaterally affected lower limb or one of the two diseased lower limbs. All nine patients showed remarkable clinical improvement in leg swelling and their

  10. 'NTA', a locally named unclear condition that causes failure to thrive ...

    African Journals Online (AJOL)

    'NTA', a locally named unclear condition that causes failure to thrive amongst under five children in southeastern Nigeria: An assessment of mothers' and caregivers' perception of its causes and management.

  11. Androgen receptor signalling in peritubular myoid cells is essential for normal differentiation and function of adult Leydig cells

    DEFF Research Database (Denmark)

    Welsh, M.; Moffat, L.; Belling, Kirstine Christensen

    2012-01-01

    Testosterone synthesis depends on normal Leydig cell (LC) development, but the mechanisms controlling this development remain unclear. We recently demonstrated that androgen receptor (AR) ablation from a proportion of testicular peritubular myoid cells (PTM-ARKO) did not affect LC number, but res......Testosterone synthesis depends on normal Leydig cell (LC) development, but the mechanisms controlling this development remain unclear. We recently demonstrated that androgen receptor (AR) ablation from a proportion of testicular peritubular myoid cells (PTM-ARKO) did not affect LC number......’ subpopulation that had arrested development and only weakly expressed INSL3, luteinizing hormone receptor, and several steroidogenic enzymes. Furthermore, unlike ‘normal’ LCs in PTM-ARKOs, the ‘abnormal’ LCs did not involute as expected in response to exogenous testosterone. Differential function of these LC...... sub-populations is likely to mean that the ‘normal’ LCs work harder to compensate for the ‘abnormal’ LCs to maintain normal serum testosterone. These findings reveal new paracrine mechanisms underlying adult LC development, which can be further investigated using PTM-ARKOs....

  12. Genomewide analyses of pathogenic and regulatory T cells of NOD ...

    Indian Academy of Sciences (India)

    Reestablishing a well-balanced population of regulatory T cells (Tregs) and pathogenic T cells (Tpaths) is necessary for diabetic patients to regain glucose control. However, the molecular mechanisms modulating functional differentiation of Tpaths and Tregs remain unclear. In this study, we anal- ysed the gene expression ...

  13. Measuring bovine gamma delta T cell function at the site of Mycobacterium bovis infection

    Science.gov (United States)

    Bovine gamma delta T cells are amongst the first cells to accumulate at the site of Mycobacterium bovis infection; however, their role in the developing lesion remains unclear. We utilized transcriptomics analysis, in situ hybridization, and a macrophage/gamma delta T cell co-culture system to eluc...

  14. 309 proteomic analysis of the blastocoel fluid and remaining cells of bovine blastocysts

    DEFF Research Database (Denmark)

    Jensen, P L; Groendahl, M L; Beck, Helle

    2012-01-01

    Human embryonic stem cells (hESC) are derived from the human blastocyst and possess the potential to differentiate into any cell type present in the adult human body. Human ESC are considered to have great potential in regenerative medicine for the future treatment of severe diseases and conditions...... such as Parkinson's disease, diabetes, and spinal cord injury. One of today's challenges in regenerative medicine is to define proper culture conditions for hESC. The natural milieu in the blastocyst may provide clues on how to improve culture conditions, and the aim of the present study was to determine...... the proteome of the blastocoel fluid and the remaining cells of bovine blastocysts. Bovine blastocysts were produced by in vitro fertilization of oocytes retrieved from slaughterhouse ovaries. The blastocoel from 195 blastocysts (1-8nL per blastocyst) were isolated by micromanipulation and analysed by nano...

  15. Heterogenic final cell cycle by chicken retinal Lim1 horizontal progenitor cells leads to heteroploid cells with a remaining replicated genome.

    Directory of Open Access Journals (Sweden)

    Shahrzad Shirazi Fard

    Full Text Available Retinal progenitor cells undergo apical mitoses during the process of interkinetic nuclear migration and newly generated post-mitotic neurons migrate to their prospective retinal layer. Whereas this is valid for most types of retinal neurons, chicken horizontal cells are generated by delayed non-apical mitoses from dedicated progenitors. The regulation of such final cell cycle is not well understood and we have studied how Lim1 expressing horizontal progenitor cells (HPCs exit the cell cycle. We have used markers for S- and G2/M-phase in combination with markers for cell cycle regulators Rb1, cyclin B1, cdc25C and p27Kip1 to characterise the final cell cycle of HPCs. The results show that Lim1+ HPCs are heterogenic with regards to when and during what phase they leave the final cell cycle. Not all horizontal cells were generated by a non-apical (basal mitosis; instead, the HPCs exhibited three different behaviours during the final cell cycle. Thirty-five percent of the Lim1+ horizontal cells was estimated to be generated by non-apical mitoses. The other horizontal cells were either generated by an interkinetic nuclear migration with an apical mitosis or by a cell cycle with an S-phase that was not followed by any mitosis. Such cells remain with replicated DNA and may be regarded as somatic heteroploids. The observed heterogeneity of the final cell cycle was also seen in the expression of Rb1, cyclin B1, cdc25C and p27Kip1. Phosphorylated Rb1-Ser608 was restricted to the Lim1+ cells that entered S-phase while cyclin B1 and cdc25C were exclusively expressed in HPCs having a basal mitosis. Only HPCs that leave the cell cycle after an apical mitosis expressed p27Kip1. We speculate that the cell cycle heterogeneity with formation of heteroploid cells may present a cellular context that contributes to the suggested propensity of these cells to generate cancer when the retinoblastoma gene is mutated.

  16. Restrictive or Liberal Red-Cell Transfusion for Cardiac Surgery

    DEFF Research Database (Denmark)

    Mazer, C David; Whitlock, Richard P; Fergusson, Dean A

    2017-01-01

    BACKGROUND: The effect of a restrictive versus liberal red-cell transfusion strategy on clinical outcomes in patients undergoing cardiac surgery remains unclear. METHODS: In this multicenter, open-label, noninferiority trial, we randomly assigned 5243 adults undergoing cardiac surgery who had a E...

  17. Gene Expression Profile of Proton Beam Irradiated Breast Cancer Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Myung Hwan; Park, Jeong Chan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Cancer stem cells (CSCs) possess characteristics associated with normal stem cells. The mechanisms regulating CSC radio-resistance, including to proton beam, remain unclear. They showed that a subset of cells expressing CD44 with weak or no CD24 expression could establish new tumors in xenograft mice. Recently, BCSC-targeting therapies have been evaluated by numerous groups. Strategies include targeting BCSC self-renewal, indirectly targeting the microenvironment, and directly killing BCSCs by chemical agents that induce differentiation, immunotherapy, and oncolytic viruses. However, the mechanisms regulating CSC radio-resistance, particularly proton beam resistance, remain unclear. The identification of CSC-related gene expression patterns would make up offer data for better understanding CSCs properties. In this study we investigated the gene expression profile of BCSCs isolation from MCF-7 cell line. Reducing BCSC resistance to pulsed proton beams is essential to improve therapeutic efficacy and decrease the 5-year recurrence rate. In this respect, the information of the level of gene expression patterns in BCSCs is attractive for understanding molecular mechanisms of radio-resistance of BCSCs.

  18. Kupffer cells promote hepatic steatosis via interleukin-1-dependent suppression of peroxisome proliferator-activated receptor activity

    NARCIS (Netherlands)

    Stienstra, R.; Saudale, F.; Duval, C.N.C.; Keshtkar, S.; Groener, C.; Rooijen, van N.; Staels, B.; Kersten, A.H.; Müller, M.R.

    2010-01-01

    Kupffer cells have been implicated in the pathogenesis of various liver diseases. However, their involvement in metabolic disorders of the liver, including fatty liver disease, remains unclear. The present study sought to determine the impact of Kupffer cells on hepatic triglyceride storage and to

  19. Glioblastoma Stem Cells Respond to Differentiation Cues but Fail to Undergo Commitment and Terminal Cell-Cycle Arrest

    Directory of Open Access Journals (Sweden)

    Helena Carén

    2015-11-01

    Full Text Available Glioblastoma (GBM is an aggressive brain tumor whose growth is driven by stem cell-like cells. BMP signaling triggers cell-cycle exit and differentiation of GBM stem cells (GSCs and, therefore, might have therapeutic value. However, the epigenetic mechanisms that accompany differentiation remain poorly defined. It is also unclear whether cell-cycle arrest is terminal. Here we find only a subset of GSC cultures exhibit astrocyte differentiation in response to BMP. Although overtly differentiated non-cycling astrocytes are generated, they remain vulnerable to cell-cycle re-entry and fail to appropriately reconfigure DNA methylation patterns. Chromatin accessibility mapping identified loci that failed to alter in response to BMP and these were enriched in SOX transcription factor-binding motifs. SOX transcription factors, therefore, may limit differentiation commitment. A similar propensity for cell-cycle re-entry and de-differentiation was observed in GSC-derived oligodendrocyte-like cells. These findings highlight significant obstacles to BMP-induced differentiation as therapy for GBM.

  20. Dynamic properties of independent chromatin domains measured by correlation spectroscopy in living cells.

    NARCIS (Netherlands)

    M. Wachsmuth (Malte); T.A. Knoch (Tobias); K. Rippe (Karsten)

    2016-01-01

    textabstractBackground: Genome organization into subchromosomal topologically associating domains (TADs) is linked to cell-type-specific gene expression programs. However, dynamic properties of such domains remain elusive, and it is unclear how domain plasticity modulates genomic accessibility for

  1. Peripheral a-helical CRF (9-41) does not reverse stress-induced mast cell dependent visceral hypersensitivity in maternally separated rats

    NARCIS (Netherlands)

    van den Wijngaard, R. M.; Stanisor, O. I.; van Diest, S. A.; Welting, O.; Wouters, M. M.; de Jonge, W. J.; Boeckxstaens, G. E.

    2012-01-01

    Background Acute stress-induced hypersensitivity to colorectal distention was shown to depend on corticotropin releasing factor (CRF)-induced mast cell degranulation. At present it remains unclear whether CRF also induces chronic poststress activation of these cells. Accordingly, the objective of

  2. Kupffer cells promote hepatic steatosis via interleukin-1beta-dependent suppression of peroxisome proliferator-activated receptor alpha activity

    NARCIS (Netherlands)

    Stienstra, Rinke; Saudale, Fredy; Duval, Caroline; Keshtkar, Shohreh; Groener, Johanna E. M.; van Rooijen, Nico; Staels, Bart; Kersten, Sander; Müller, Michael

    2010-01-01

    Kupffer cells have been implicated in the pathogenesis of various liver diseases. However, their involvement in metabolic disorders of the liver, including fatty liver disease, remains unclear. The present study sought to determine the impact of Kupffer cells on hepatic triglyceride storage and to

  3. Industry remains stuck in a transitional mode

    International Nuclear Information System (INIS)

    Garb, F.A.

    1991-01-01

    The near future for industry remains foggy for several obvious reasons. The shake-up of the Soviet Union and how the pieces will reform remains unclear. How successful efforts are to privatize government oil company operations around the world has yet to be determined. A long sought peace in the Middle East seems to be inching closer, but will this continue? If it does continue, what impact will it have on world energy policy? Will American companies, which are now transferring their attention to foreign E and P, also maintain an interest in domestic activities? Is the U.S. economy really on the upswing? We are told that the worst of the recession is over, but try telling this to thousands of workers in the oil patch who are being released monthly by the big players in domestic operations. This paper reports that 1992 should be a better year than 1991, if measured in opportunity. There are more exploration and acquisition options available, both domestically and internationally, than there have been in years. Probably more opportunities exist than there are players-certainly more than can be funded with current financial resources

  4. Clinical trials for stem cell transplantation: when are they needed?

    Science.gov (United States)

    Van Pham, Phuc

    2016-04-27

    In recent years, both stem cell research and the clinical application of these promising cells have increased rapidly. About 1000 clinical trials using stem cells have to date been performed globally. More importantly, more than 10 stem cell-based products have been approved in some countries. With the rapid growth of stem cell applications, some countries have used clinical trials as a tool to diminish the rate of clinical stem cell applications. However, the point at which stem cell clinical trials are essential remains unclear. This commentary discusses when stem cell clinical trials are essential for stem cell transplantation therapies.

  5. The microRNA-200 family coordinately regulates cell adhesion and proliferation in hair morphogenesis.

    Science.gov (United States)

    Hoefert, Jaimee E; Bjerke, Glen A; Wang, Dongmei; Yi, Rui

    2018-06-04

    The microRNA (miRNA)-200 (miR-200) family is highly expressed in epithelial cells and frequently lost in metastatic cancer. Despite intensive studies into their roles in cancer, their targets and functions in normal epithelial tissues remain unclear. Importantly, it remains unclear how the two subfamilies of the five-miRNA family, distinguished by a single nucleotide within the seed region, regulate their targets. By directly ligating miRNAs to their targeted mRNA regions, we identify numerous miR-200 targets involved in the regulation of focal adhesion, actin cytoskeleton, cell cycle, and Hippo/Yap signaling. The two subfamilies bind to largely distinct target sites, but many genes are coordinately regulated by both subfamilies. Using inducible and knockout mouse models, we show that the miR-200 family regulates cell adhesion and orientation in the hair germ, contributing to precise cell fate specification and hair morphogenesis. Our findings demonstrate that combinatorial targeting of many genes is critical for miRNA function and provide new insights into miR-200's functions. © 2018 Hoefert et al.

  6. Nicotine induces cell proliferation in association with cyclin D1 up-regulation and inhibits cell differentiation in association with p53 regulation in a murine pre-osteoblastic cell line

    International Nuclear Information System (INIS)

    Sato, Tsuyoshi; Abe, Takahiro; Nakamoto, Norimichi; Tomaru, Yasuhisa; Koshikiya, Noboru; Nojima, Junya; Kokabu, Shoichiro; Sakata, Yasuaki; Kobayashi, Akio; Yoda, Tetsuya

    2008-01-01

    Recent studies have suggested that nicotine critically affects bone metabolism. Many studies have examined the effects of nicotine on proliferation and differentiation, but the underlying molecular mechanisms remain unclear. We examined cell cycle regulators involved in the proliferation and differentiation of MC3T3-E1 cells. Nicotine induced cell proliferation in association with p53 down-regulation and cyclin D1 up-regulation. In differentiated cells, nicotine reduced alkaline phosphatase activity and mineralized nodule formation in dose-dependent manners. Furthermore, p53 expression was sustained in nicotine-treated cells during differentiation. These findings indicate that nicotine promotes the cell cycle and inhibits differentiation in association with p53 regulation in pre-osteoblastic cells

  7. Regulation of CCR7-dependent cell migration through?CCR7 homodimer formation

    OpenAIRE

    Kobayashi, Daichi; Endo, Masataka; Ochi, Hirotaka; Hojo, Hironobu; Miyasaka, Masayuki; Hayasaka, Haruko

    2017-01-01

    The chemokine receptor CCR7 contributes to various physiological and pathological processes including T cell maturation, T cell migration from the blood into secondary lymphoid tissues, and tumor cell metastasis to lymph nodes. Although a previous study suggested that the efficacy of CCR7 ligand-dependent T cell migration correlates with CCR7 homo- and heterodimer formation, the exact extent of contribution of the CCR7 dimerization remains unclear. Here, by inducing or disrupting CCR7 dimers,...

  8. Cerebral lesions on 7 tesla MRI in patients with sickle cell anemia

    NARCIS (Netherlands)

    van der Land, Veronica; Zwanenburg, Jaco J. M.; Fijnvandraat, Karin; Biemond, Bart J.; Hendrikse, Jeroen; Mutsaerts, Henri J. M. M.; Visser, Fredy; Wardlaw, Joanna M.; Nederveen, Aart J.; Majoie, Charles B. L. M.; Nederkoorn, Paul J.

    2015-01-01

    Patients with sickle cell anemia (SCA) are at a high risk to develop cerebral damage. Most common are silent cerebral infarctions (SCIs), visible as white matter hyperintensities (WMHs) on MRI in a patient without neurological deficits. The etiology of SCIs remains largely unclear. In addition,

  9. Selective, autoantibody-immune complex mediated proportional and functional changes of specific NK-cell subsets in early seropositive but not seronegative rheumatoid arthritis

    NARCIS (Netherlands)

    Chalan, P.; Brouwer, Liesbeth; Bijzet, J.; Kroesen, B.-J.; Boots, Annemieke

    2015-01-01

    Background: Despite substantial data demonstrating NK-cell impairment in rheumatoid arthritis (RA), the exact role of NK-cells in RA immunopathogenesis remains unclear. Objectives: We studied the involvement of CD56dim and CD56bright NK-cells in the early stages of RA development to elucidate their

  10. Aging increases cell-to-cell transcriptional variability upon immune stimulation.

    Science.gov (United States)

    Martinez-Jimenez, Celia Pilar; Eling, Nils; Chen, Hung-Chang; Vallejos, Catalina A; Kolodziejczyk, Aleksandra A; Connor, Frances; Stojic, Lovorka; Rayner, Timothy F; Stubbington, Michael J T; Teichmann, Sarah A; de la Roche, Maike; Marioni, John C; Odom, Duncan T

    2017-03-31

    Aging is characterized by progressive loss of physiological and cellular functions, but the molecular basis of this decline remains unclear. We explored how aging affects transcriptional dynamics using single-cell RNA sequencing of unstimulated and stimulated naïve and effector memory CD4 + T cells from young and old mice from two divergent species. In young animals, immunological activation drives a conserved transcriptomic switch, resulting in tightly controlled gene expression characterized by a strong up-regulation of a core activation program, coupled with a decrease in cell-to-cell variability. Aging perturbed the activation of this core program and increased expression heterogeneity across populations of cells in both species. These discoveries suggest that increased cell-to-cell transcriptional variability will be a hallmark feature of aging across most, if not all, mammalian tissues. Copyright © 2017, American Association for the Advancement of Science.

  11. Self-reactive CD4+ T cells and B cells in the blood in health and autoimmune disease: increased frequency of thyroglobulin-reactive cells in Graves' disease

    DEFF Research Database (Denmark)

    Nielsen, Claus H; Moeller, Ane Christine; Hegedüs, Laszlo

    2006-01-01

    The mechanisms underlying activation of potentially self-reactive circulating B cells and T cells remain unclear. We measured the uptake of a self-antigen, thyroglobulin, by antigen presenting cells, and the subsequent proliferation of CD4(+) T cells and B cells from healthy controls and patients...... with autoimmune thyroiditis. In Hashimoto's thyroiditis, B cells bound increased amounts of thyroglobulin in a complement- and autoantibody-dependent manner, and the thyroglobulin-elicited proliferation of CD4(+) T cells and B cells was complement dependent. Increased proportions of Tg-responsive CD4(+) T cells...... and B cells were found in patients with Graves' disease. Notably, both patient groups and healthy controls exhibited higher proliferative responses to thyroglobulin than to a foreign recall antigen, tetanus toxoid. Our results suggest that self-tolerance can be broken by exposure of circulating...

  12. Results of surgical treatment of T4 non-small cell lung cancer

    NARCIS (Netherlands)

    Pitz, CCM; de la Riviere, AB; van Swieten, HA; Westermann, CJJ; Lammers, JWJ; van den Bosch, JMM

    2003-01-01

    Objective: Because of location and invasion of surrounding structures, the role of surgical treatment for T4 tumors remains unclear. Extended resections carry a high mortality and should be restricted for selected patients. This study clarifies the selection process in non-small cell T4 tumors with

  13. Radiosensitivity of normal human epidermal cells in culture

    International Nuclear Information System (INIS)

    Dover, R.; Potten, C.S.

    1983-01-01

    Using an in vitro culture system the authors have derived #betta#-radiation survival curves over a dose range 0-8 Gy for the clonogenic cells of normal human epidermis. The culture system used allows the epidermal cells to stratify and form a multi-layered sheet of keratinizing cells. The cultures appear to be a very good model for epidermis in vivo. The survival curves show a population which is apparently more sensitive than murine epidermis in vivo. It remains unclear whether this is an intrinsic difference between the species or is a consequence of the in vitro cultivation of the human cells. (author)

  14. Murid herpesvirus-4 exploits dendritic cells to infect B cells.

    Directory of Open Access Journals (Sweden)

    Miguel Gaspar

    2011-11-01

    Full Text Available Dendritic cells (DCs play a central role in initiating immune responses. Some persistent viruses infect DCs and can disrupt their functions in vitro. However, these viruses remain strongly immunogenic in vivo. Thus what role DC infection plays in the pathogenesis of persistent infections is unclear. Here we show that a persistent, B cell-tropic gamma-herpesvirus, Murid Herpesvirus-4 (MuHV-4, infects DCs early after host entry, before it establishes a substantial infection of B cells. DC-specific virus marking by cre-lox recombination revealed that a significant fraction of the virus latent in B cells had passed through a DC, and a virus attenuated for replication in DCs was impaired in B cell colonization. In vitro MuHV-4 dramatically altered the DC cytoskeleton, suggesting that it manipulates DC migration and shape in order to spread. MuHV-4 therefore uses DCs to colonize B cells.

  15. Cell-Cell Contact Area Affects Notch Signaling and Notch-Dependent Patterning.

    Science.gov (United States)

    Shaya, Oren; Binshtok, Udi; Hersch, Micha; Rivkin, Dmitri; Weinreb, Sheila; Amir-Zilberstein, Liat; Khamaisi, Bassma; Oppenheim, Olya; Desai, Ravi A; Goodyear, Richard J; Richardson, Guy P; Chen, Christopher S; Sprinzak, David

    2017-03-13

    During development, cells undergo dramatic changes in their morphology. By affecting contact geometry, these morphological changes could influence cellular communication. However, it has remained unclear whether and how signaling depends on contact geometry. This question is particularly relevant for Notch signaling, which coordinates neighboring cell fates through direct cell-cell signaling. Using micropatterning with a receptor trans-endocytosis assay, we show that signaling between pairs of cells correlates with their contact area. This relationship extends across contact diameters ranging from micrometers to tens of micrometers. Mathematical modeling predicts that dependence of signaling on contact area can bias cellular differentiation in Notch-mediated lateral inhibition processes, such that smaller cells are more likely to differentiate into signal-producing cells. Consistent with this prediction, analysis of developing chick inner ear revealed that ligand-producing hair cell precursors have smaller apical footprints than non-hair cells. Together, these results highlight the influence of cell morphology on fate determination processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Decorin expression in quiescent myogenic cells

    International Nuclear Information System (INIS)

    Nishimura, Takanori; Nozu, Kenjiro; Kishioka, Yasuhiro; Wakamatsu, Jun-ichi; Hattori, Akihito

    2008-01-01

    Satellite cells are quiescent muscle stem cells that promote postnatal muscle growth and repair. When satellite cells are activated by myotrauma, they proliferate, migrate, differentiate, and ultimately fuse to existing myofibers. The remainder of these cells do not differentiate, but instead return to quiescence and remain in a quiescent state until activation begins the process again. This ability to maintain their own population is important for skeletal muscle to maintain the capability to repair during postnatal life. However, the mechanisms by which satellite cells return to quiescence and maintain the quiescent state are still unclear. Here, we demonstrated that decorin mRNA expression was high in cell cultures containing a higher ratio of quiescent satellite cells when satellite cells were stimulated with various concentrations of hepatocyte growth factor. This result suggests that quiescent satellite cells express decorin at a high level compared to activated satellite cells. Furthermore, we examined the expression of decorin in reserve cells, which were undifferentiated myoblasts remaining after induction of differentiation by serum-deprivation. Decorin mRNA levels in reserve cells were higher than those in differentiated myotubes and growing myoblasts. These results suggest that decorin participates in the quiescence of myogenic cells

  17. Luminal Cells Are Favored as the Cell of Origin for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Zhu A. Wang

    2014-09-01

    Full Text Available The identification of cell types of origin for cancer has important implications for tumor stratification and personalized treatment. For prostate cancer, the cell of origin has been intensively studied, but it has remained unclear whether basal or luminal epithelial cells, or both, represent cells of origin under physiological conditions in vivo. Here, we use a novel lineage-tracing strategy to assess the cell of origin in a diverse range of mouse models, including Nkx3.1+/−; Pten+/−, Pten+/−, Hi-Myc, and TRAMP mice, as well as a hormonal carcinogenesis model. Our results show that luminal cells are consistently the observed cell of origin for each model in situ; however, explanted basal cells from these mice can generate tumors in grafts. Consequently, we propose that luminal cells are favored as cells of origin in many contexts, whereas basal cells only give rise to tumors after differentiation into luminal cells.

  18. Elimination of remaining undifferentiated induced pluripotent stem cells in the process of human cardiac cell sheet fabrication using a methionine-free culture condition.

    Science.gov (United States)

    Matsuura, Katsuhisa; Kodama, Fumiko; Sugiyama, Kasumi; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Okano, Teruo

    2015-03-01

    Cardiac tissue engineering is a promising method for regenerative medicine. Although we have developed human cardiac cell sheets by integration of cell sheet-based tissue engineering and scalable bioreactor culture, the risk of contamination by induced pluripotent stem (iPS) cells in cardiac cell sheets remains unresolved. In the present study, we established a novel culture method to fabricate human cardiac cell sheets with a decreased risk of iPS cell contamination while maintaining viabilities of iPS cell-derived cells, including cardiomyocytes and fibroblasts, using a methionine-free culture condition. When cultured in the methionine-free condition, human iPS cells did not survive without feeder cells and could not proliferate or form colonies on feeder cells or in coculture with cells for cardiac cell sheet fabrication. When iPS cell-derived cells after the cardiac differentiation were transiently cultured in the methionine-free condition, gene expression of OCT3/4 and NANOG was downregulated significantly compared with that in the standard culture condition. Furthermore, in fabricated cardiac cell sheets, spontaneous and synchronous beating was observed in the whole area while maintaining or upregulating the expression of various cardiac and extracellular matrix genes. These findings suggest that human iPS cells are methionine dependent and a methionine-free culture condition for cardiac cell sheet fabrication might reduce the risk of iPS cell contamination.

  19. Centrosomal protein 55 activates NF-?B signalling and promotes pancreatic cancer cells aggressiveness

    OpenAIRE

    Peng, Tao; Zhou, Wei; Guo, Feng; Wu, He-shui; Wang, Chun-you; Wang, Li; Yang, Zhi-yong

    2017-01-01

    Centrosomal protein 55 (CEP55) is a microtubule-bundling protein that participants in cell mitosis. It is overexpressed in several solid tumours and promotes the growth and invasion of cancer cells. However, the role of CEP55 in pancreatic cancer (PANC) remains unclear. Herein, upregulated expression of CEP55 (associated with poor prognosis) was detected in PANC using quantitative real-time reverse transcription PCR, western blotting, and immunohistochemistry. Cell migration, colony formation...

  20. Llgl1 Connects Cell Polarity with Cell-Cell Adhesion in Embryonic Neural Stem Cells.

    Science.gov (United States)

    Jossin, Yves; Lee, Minhui; Klezovitch, Olga; Kon, Elif; Cossard, Alexia; Lien, Wen-Hui; Fernandez, Tania E; Cooper, Jonathan A; Vasioukhin, Valera

    2017-06-05

    Malformations of the cerebral cortex (MCCs) are devastating developmental disorders. We report here that mice with embryonic neural stem-cell-specific deletion of Llgl1 (Nestin-Cre/Llgl1 fl/fl ), a mammalian ortholog of the Drosophila cell polarity gene lgl, exhibit MCCs resembling severe periventricular heterotopia (PH). Immunohistochemical analyses and live cortical imaging of PH formation revealed that disruption of apical junctional complexes (AJCs) was responsible for PH in Nestin-Cre/Llgl1 fl/fl brains. While it is well known that cell polarity proteins govern the formation of AJCs, the exact mechanisms remain unclear. We show that LLGL1 directly binds to and promotes internalization of N-cadherin, and N-cadherin/LLGL1 interaction is inhibited by atypical protein kinase C-mediated phosphorylation of LLGL1, restricting the accumulation of AJCs to the basolateral-apical boundary. Disruption of the N-cadherin-LLGL1 interaction during cortical development in vivo is sufficient for PH. These findings reveal a mechanism responsible for the physical and functional connection between cell polarity and cell-cell adhesion machineries in mammalian cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Interleukin-6 and intercellular cell adhesion molecule-1 expression remains elevated in revived live endothelial cells following spaceflight.

    Science.gov (United States)

    Muid, S; Froemming, G R A; Ali, A M; Nawawi, H

    2013-12-01

    The effects of spaceflight on cardiovascular health are not necessarily seen immediately after astronauts have returned but can be delayed. It is important to investigate the long term effects of spaceflight on protein and gene expression of inflammation and endothelial activation as a predictor for the development of atherosclerosis and potential cardiovascular problems. The objectives of this study were to investigate the (a) protein and gene expression of inflammation and endothelial activation, (b) expression of nuclear factor kappa B (NFκB), signal transducer and activator of transcription-3 (STAT-3) and endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVEC) 3 months post-space flight travel compared to ground controls. HUVEC cultured on microcarriers in fluid processing apparatus were flown to the International Space Station (ISS) by the Soyuz TMA-11 rocket. After landing, the cells were detached from microcarriers and recultured in T-25 cm(2) culture flasks (Revived HUVEC). Soluble protein expression of IL-6, TNF-α, ICAM-1, VCAM-1 and e-selectin were measured by ELISA. Gene expression of these markers and in addition NFκB, STAT-3 and eNOS were measured. Spaceflight induced IL-6 and ICAM-1 remain elevated even after 3 months post spaceflight travel and this is mediated via STAT-3 pathway. The downregulation of eNOS expression in revived HUVEC cells suggests a reduced protection of the cells and the surrounding vessels against future insults that may lead to atherosclerosis. It would be crucial to explore preventive measures, in relation to atherosclerosis and its related complications.

  2. Is this the end of cytotoxic chemotherapy in Merkel cell carcinoma?

    OpenAIRE

    Rabinowits, Guilherme

    2017-01-01

    Guilherme Rabinowits Department of Medical Oncology, Center for Head and Neck Oncology, Dana-Farber Cancer Institute, Boston, MA, USA Abstract: Although cytotoxic chemotherapy has been used often in the management of Merkel cell carcinoma (MCC), its benefit remains uncertain. Despite being considered a chemosensitive disease, the duration of response is generally short, and the survival benefit is unclear. With the recent FDA approval of the anti-programmed cell death ligand 1 (PD-L1) antib...

  3. Lead toxicity masquerading as sickle cell crisis.

    Science.gov (United States)

    Nelson, M S; Chisolm, J J

    1986-06-01

    We recently saw a 12-year-old black boy with known sickle cell disease who had been seen many times for abdominal pain thought to be secondary to a vasoocclusive crisis. The patient eventually was admitted, after a seizure and the onset of obtundation. The etiology of his acute encephalopathy remained unclear until bone films of his knees fortuitously revealed "lead lines." The patient was treated and did well subsequently. This case emphasizes the importance of considering other diagnoses when a sickle cell patient presents with a crisis.

  4. Mesenchymal stem cells display different gene expression profiles compared to hyaline and elastic chondrocytes

    OpenAIRE

    Zhai, Li-Jie; Zhao, Ke-Qing; Wang, Zhi-Qiang; Feng, Ya; Xing, Shuang-Chun

    2011-01-01

    Cartilage has a poor intrinsic repair capacity, requiring surgical intervention to effect biological repair. Tissue engineering technologies or regenerative medicine strategies are currently being employed to address cartilage repair. Mesenchymal stem cells (MSCs) are considered to be an excellent cell source for this application. However, the different gene expression profiles between the MSCs and differentiated cartilage remain unclear. In this report, we first examined the gene expression ...

  5. Analysis of Cell Biomechanics Response to Gravity:A Fluids for Biology Study Utilizing NASA Glenns Zero Gravity Research Facility

    Science.gov (United States)

    Bomani, Bilal M. M.; Kassemi, Mohammad; Neumann, Eric S.

    2016-01-01

    It remains unclear how biological cells sense and respond to gravitational forces. Leading scientists state that a large gap exists in the understanding of physiological and molecular adaptation that occurs as biology enters the spaceflight realm. We are seeking a method to fully understand how cells sense microgravity/gravity and what triggers their response.

  6. 3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration

    OpenAIRE

    Juang, Jyuhn-Huarng; Kuo, Chien-Hung; Peng, Shih-Jung; Tang, Shiue-Cheng

    2015-01-01

    The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histolo...

  7. Fetal liver stromal cells promote hematopoietic cell expansion

    International Nuclear Information System (INIS)

    Zhou, Kun; Hu, Caihong; Zhou, Zhigang; Huang, Lifang; Liu, Wenli; Sun, Hanying

    2009-01-01

    Future application of hematopoietic stem and progenitor cells (HSPCs) in clinical therapies largely depends on their successful expansion in vitro. Fetal liver (FL) is a unique hematopoietic organ in which hematopoietic cells markedly expand in number, but the mechanisms involved remain unclear. Stromal cells (StroCs) have been suggested to provide a suitable cellular environment for in vitro expansion of HSPCs. In this study, murine StroCs derived from FL at E14.5, with a high level of Sonic hedgehog (Shh) and Wnt expression, were found to have an increased ability to support the proliferation of HSPCs. This effect was inhibited by blocking Shh signaling. Supplementation with soluble Shh-N promoted the proliferation of hematopoietic cells by activating Wnt signaling. Our findings suggest that FL-derived StroCs support proliferation of HSPCs via Shh inducing an autocrine Wnt signaling loop. The use of FL-derived StroCs and regulation of the Shh pathway might further enhance HPSC expansion.

  8. Analysis of mitosis and antimitotic drug responses in tumors by in vivo microscopy and single-cell pharmacodynamics

    NARCIS (Netherlands)

    Orth, James D; Kohler, Rainer H; Foijer, Floris; Sorger, Peter K; Weissleder, Ralph; Mitchison, Timothy J

    2011-01-01

    Cancer relies upon frequent or abnormal cell division, but how the tumor microenvironment affects mitotic processes in vivo remains unclear, largely due to the technical challenges of optical access, spatial resolution, and motion. We developed high-resolution in vivo microscopy methods to visualize

  9. Natural autoantibodies and complement promote the uptake of a self antigen, human thyroglobulin, by B cells and the proliferation of thyroglobulin-reactive CD4(+) T cells in healthy individuals

    DEFF Research Database (Denmark)

    Nielsen, C H; Leslie, R G; Jepsen, B S

    2001-01-01

    Serum from normal individuals contains substantial amounts of natural antibodies (NA) capable of recognizing self antigens. However, the physiological implications of this autoreactivity remain unclear. We have examined the role of self-reactive NA and complement in mediating the uptake of human...... cells are prerequisites for the proliferation of Tg-reactive CD4(+) T cells, suggesting a novel role for natural autoantibodies and complement in the regulation of autoreactivity under physiological conditions....

  10. Defective TFH Cell Function and Increased TFR Cells Contribute to Defective Antibody Production in Aging.

    Science.gov (United States)

    Sage, Peter T; Tan, Catherine L; Freeman, Gordon J; Haigis, Marcia; Sharpe, Arlene H

    2015-07-14

    Defective antibody production in aging is broadly attributed to immunosenescence. However, the precise immunological mechanisms remain unclear. Here, we demonstrate an increase in the ratio of inhibitory T follicular regulatory (TFR) cells to stimulatory T follicular helper (TFH) cells in aged mice. Aged TFH and TFR cells are phenotypically distinct from those in young mice, exhibiting increased programmed cell death protein-1 expression but decreased ICOS expression. Aged TFH cells exhibit defective antigen-specific responses, and programmed cell death protein-ligand 1 blockade can partially rescue TFH cell function. In contrast, young and aged TFR cells have similar suppressive capacity on a per-cell basis in vitro and in vivo. Together, these studies reveal mechanisms contributing to defective humoral immunity in aging: an increase in suppressive TFR cells combined with impaired function of aged TFH cells results in reduced T-cell-dependent antibody responses in aged mice. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Knockdown of Indian hedgehog protein induces an inhibition of cell growth and differentiation in osteoblast MC3T3-E1 cells

    OpenAIRE

    Deng, Ang; Zhang, Hongqi; Hu, Minyu; Liu, Shaohua; Gao, Qile; Wang, Yuxiang; Guo, Chaofeng

    2017-01-01

    Indian hedgehog protein (Ihh) is evolutionarily conserved and serves important roles in controlling the differentiation of progenitor cells into osteoblasts. Ihh null mutant mice exhibit a failure of osteoblast development in endochondral bone. Although studies have demonstrated that Ihh signaling is a potent local factor that regulates osteoblast differentiation, the specific transcription factors that determine osteoblast differentiation remain unclear. Further studies are required to deter...

  12. During development intense Sox2 expression marks not only Prox1-expressing taste bud cell but also perigemmal cell lineages.

    Science.gov (United States)

    Nakayama, Ayumi; Miura, Hirohito; Ooki, Makoto; Harada, Shuitsu

    2015-03-01

    Sox2 is proposed to regulate the differentiation of bipotential progenitor cells into taste bud cells. However, detailed expression of Sox2 remains unclear. In this report, Sox2 expression during taste bud development in the fungiform (FF), circumvallate (CV) and soft palate (SP) areas is examined together with Prox1. First, we immunohistochemically checked Prox1 expression in adults and found that almost all taste bud cells are Prox1-positive. During FF development, intense Sox2 expression was restricted to taste bud primordia expressing Prox1 at E12.5. However, at E14.5, Sox2 was intensely expressed outside the developing taste buds resolving to perigemmal Sox2 expression in adults. In the SP, at E14.5, taste bud primordia emerged as Prox1-expressing cell clusters. However, intense Sox2 expression was not restricted to taste bud primordia but was detected widely in the epithelium. During development, Sox2 expression outside developing taste buds was generally down-regulated but was retained in the perigemmal region similarly to that in the FF. In the CV, the initial stage of taste bud development remained unclear because of the lack of taste bud primordia comparable to that in the FF and SP. Here, we show that Prox1-expressing cells appear in the apical epithelium at E12.5, in the inner trench wall at E17.5 and in the outer trench wall at E18.5. Sox2 was again not restricted to developing taste bud cells expressing Prox1 during CV development. The expression patterns support that Sox2 does not serve as a cell fate selector between taste bud cells and surrounding keratinocytes but rather may contribute to them both.

  13. Endothelial Cells Control Pancreatic Cell Fate at Defined Stages through EGFL7 Signaling

    Directory of Open Access Journals (Sweden)

    Der-I Kao

    2015-02-01

    Full Text Available Although endothelial cells have been shown to affect mouse pancreatic development, their precise function in human development remains unclear. Using a coculture system containing human embryonic stem cell (hESC-derived progenitors and endothelial cells, we found that endothelial cells play a stage-dependent role in pancreatic development, in which they maintain pancreatic progenitor (PP self-renewal and impair further differentiation into hormone-expressing cells. The mechanistic studies suggest that the endothelial cells act through the secretion of EGFL7. Consistently, endothelial overexpression of EGFL7 in vivo using a transgenic mouse model resulted in an increase of PP proliferation rate and a decrease of differentiation toward endocrine cells. These studies not only identified the role of EGFL7 as the molecular handle involved in the crosstalk between endothelium and pancreatic epithelium, but also provide a paradigm for using hESC stepwise differentiation to dissect the stage-dependent roles of signals controlling organogenesis.

  14. Oseltamivir Prophylaxis Reduces Inflammation and Facilitates Establishment of Cross-Strain Protective T Cell Memory to Influenza Viruses

    OpenAIRE

    Bird, Nicola L.; Olson, Matthew R.; Hurt, Aeron C.; Oshansky, Christine M.; Oh, Ding Yuan; Reading, Patrick C.; Chua, Brendon Y.; Sun, Yilun; Tang, Li; Handel, Andreas; Jackson, David C.; Turner, Stephen J.; Thomas, Paul G.; Kedzierska, Katherine

    2015-01-01

    CD8(+) T cells directed against conserved viral regions elicit broad immunity against distinct influenza viruses, promote rapid virus elimination and enhanced host recovery. The influenza neuraminidase inhibitor, oseltamivir, is prescribed for therapy and prophylaxis, although it remains unclear how the drug impacts disease severity and establishment of effector and memory CD8(+) T cell immunity. We dissected the effects of oseltamivir on viral replication, inflammation, acute CD8(+) T cell r...

  15. Persistent seropositivity for yellow fever in a previously vaccinated autologous hematopoietic stem cell transplantation recipient.

    Science.gov (United States)

    Hayakawa, Kayoko; Takasaki, Tomohiko; Tsunemine, Hiroko; Kanagawa, Shuzo; Kutsuna, Satoshi; Takeshita, Nozomi; Mawatari, Momoko; Fujiya, Yoshihiro; Yamamoto, Kei; Ohmagari, Norio; Kato, Yasuyuki

    2015-08-01

    The duration of a protective level of yellow fever antibodies after autologous hematopoietic stem cell transplantation in a previously vaccinated person is unclear. The case of a patient who had previously been vaccinated for yellow fever and who remained seropositive for 22 months after autologous peripheral blood stem cell transplantation for malignant lymphoma is described herein. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Effects of xanthosine on gene expression of mammary epithelial cells using RNA sequencing of goat milk fat globules

    Science.gov (United States)

    Although intramammary xanthosine (XS) treatment was reported to increase the mammary stem cell population and milk yield in bovine and caprine, underlying molecular mechanisms remain unclear. The goal of this study was to evaluate effects of XS treatment on the mammary transcriptome in early lactati...

  17. Extinct type of human parvovirus B19 persists in tonsillar B cells

    OpenAIRE

    Pyöriä, Lari; Toppinen, Mari; Mantyla, Elina; Hedman, Lea; Aaltonen, Leena-Maija; Vihinen-Ranta, Maija; Ilmarinen, Taru; Soderlund-Venermo, Maria; Hedman, Klaus; Perdomo, Maria

    2017-01-01

    Parvovirus B19 (B19V) DNA persists lifelong in human tissues, but the cell type harbouring it remains unclear. We here explore B19V DNA distribution in B, T and monocyte cell lineages of recently excised tonsillar tissues from 77 individuals with an age range of 2?69 years. We show that B19V DNA is most frequent and abundant among B cells, and within them we find a B19V genotype that vanished from circulation >40 years ago. Since re-infection or re-activation are unlikely with this virus type...

  18. 76 FR 23732 - Margin Requirements for Uncleared Swaps for Swap Dealers and Major Swap Participants

    Science.gov (United States)

    2011-04-28

    ... the currency in which payment obligations under the swap are required to be settled; Any obligation... RIN 3038--AC97 Margin Requirements for Uncleared Swaps for Swap Dealers and Major Swap Participants... the Commission to adopt capital and initial and variation margin requirements for certain swap dealers...

  19. Single-cell-derived mesenchymal stem cells overexpressing Csx/Nkx2.5 and GATA4 undergo the stochastic cardiomyogenic fate and behave like transient amplifying cells

    International Nuclear Information System (INIS)

    Yamada, Yoji; Sakurada, Kazuhiro; Takeda, Yukiji; Gojo, Satoshi; Umezawa, Akihiro

    2007-01-01

    Bone marrow-derived stromal cells can give rise to cardiomyocytes as well as adipocytes, osteocytes, and chondrocytes in vitro. The existence of mesenchymal stem cells has been proposed, but it remains unclear if a single-cell-derived stem cell stochastically commits toward a cardiac lineage. By single-cell marking, we performed a follow-up study of individual cells during the differentiation of 9-15c mesenchymal stromal cells derived from bone marrow cells. Three types of cells, i.e., cardiac myoblasts, cardiac progenitors and multipotent stem cells were differentiated from a single cell, implying that cardiomyocytes are generated stochastically from a single-cell-derived stem cell. We also demonstrated that overexpression of Csx/Nkx2.5 and GATA4, precardiac mesodermal transcription factors, enhanced cardiomyogenic differentiation of 9-15c cells, and the frequency of cardiomyogenic differentiation was increased by co-culturing with fetal cardiomyocytes. Single-cell-derived mesenchymal stem cells overexpressing Csx/Nkx2.5 and GATA4 behaved like cardiac transient amplifying cells, and still retained their plasticity in vivo

  20. Involvement of IRF4 dependent dendritic cells in T cell dependent colitis

    DEFF Research Database (Denmark)

    Pool, Lieneke; Rivollier, Aymeric Marie Christian; Agace, William Winston

    in genetically susceptible individuals and pathogenic CD4+ T cells, which accumulate in the inflamed mucosa, are believed to be key drivers of the disease. While dendritic cells (DCs) are important in the priming of intestinal adaptive immunity and tolerance their role in the initiation and perpetuation...... of chronic intestinal inflammation remains unclear. In the current study we used the CD45RBhi T cell transfer model of colitis to determine the role of IRF4 dependent DCs in intestinal inflammation. In this model naïve CD4+ T cells when transferred into RAG-/- mice, proliferate and expand in response...... to bacterial derived luminal antigen, localize to the intestinal mucosa and induce colitis. Adoptive transfer of naïve T cells into CD11cCre.IRF4fl/fl.RAG-1-/- mice resulted in reduced monocyte recruitment to the intestine and mesenteric lymph nodes (MLN) compared to Cre- controls. Inflammatory cytokines...

  1. Folate deprivation induces cell cycle arrest at G0/G1 phase and apoptosis in hippocampal neuron cells through down-regulation of IGF-1 signaling pathway.

    Science.gov (United States)

    Yang, Yang; Li, Xi; Sun, Qinwei; He, Bin; Jia, Yimin; Cai, Demin; Zhao, Ruqian

    2016-10-01

    Folate deficiency contributes to impaired adult hippocampal neurogenesis, yet the mechanisms remain unclear. Here we use HT-22 hippocampal neuron cells as model to investigate the effect of folate deprivation (FD) on cell proliferation and apoptosis, and to elucidate the underlying mechanism. FD caused cell cycle arrest at G0/G1 phase and increased the rate of apoptosis, which was associated with disrupted expression of folate transport and methyl transfer genes. FOLR1 and SLC46A1 were (Pmethyl transfer pathway and hypermethylation of IGF-1 gene promoter. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. CD8+ T Cells Mediate Female-Dominant IL-4 Production and Airway Inflammation in Allergic Asthma

    OpenAIRE

    Ito, Chihiro; Okuyama-Dobashi, Kaori; Miyasaka, Tomomitsu; Masuda, Chiaki; Sato, Miki; Kawano, Tasuku; Ohkawara, Yuichi; Kikuchi, Toshiaki; Takayanagi, Motoaki; Ohno, Isao

    2015-01-01

    The prevalence and severity of bronchial asthma are higher in females than in males after puberty. Although antigen-specific CD8+ T cells play an important role in the development of asthma through their suppressive effect on cytokine production, the contribution of CD8+ T cells to sex differences in asthmatic responses remains unclear. In the present study, we investigated the sex-specific effect of CD8+ T cells in the suppression of asthma using an ovalbumin mouse model of asthma. The numbe...

  3. Extremely low frequency electromagnetic field exposure does not modulate Toll-like receptor signaling in human peripheral blood mononuclear cells

    NARCIS (Netherlands)

    Kleijn, de S.; Bouwens, M.; Verburg-van Kemenade, B.M.L.; Cuppen, J.J.M.; Ferwerda, G.; Hermans, P.

    2011-01-01

    The effects of extremely low frequency electromagnetic fields (ELF-EMF) on human health remain unclear. It has been reported that ELF-EMF may modulate the innate immune response to microorganisms in animal models and mammalian cell-lines. With the recently gained insight in innate immune signaling

  4. Postoperative radiotherapy in stage III non-small cell lung cancer: Is a reassessment necessary in modern times?

    OpenAIRE

    Billiet, Charlotte

    2017-01-01

    Background: The role of postoperative radiation therapy (PORT) in patients with completely resected non-small cell lung cancer (NSCLC) with pathologically involved mediastinal lymph nodes (N2) remains unclear. Despite a reduction of local recurrence (LR), its effect on overall survival (OS) remains unproven. Therefore we conducted a review of the current literature. Methods: To investigate the benefit and safety of modern PORT, we identified published phase III trials for PORT. We inves...

  5. Dysregulation of gene expression in the artificial human trisomy cells of chromosome 8 associated with transformed cell phenotypes.

    Directory of Open Access Journals (Sweden)

    Hisakatsu Nawata

    Full Text Available A change in chromosome number, known as aneuploidy, is a common characteristic of cancer. Aneuploidy disrupts gene expression in human cancer cells and immortalized human epithelial cells, but not in normal human cells. However, the relationship between aneuploidy and cancer remains unclear. To study the effects of aneuploidy in normal human cells, we generated artificial cells of human primary fibroblast having three chromosome 8 (trisomy 8 cells by using microcell-mediated chromosome transfer technique. In addition to decreased proliferation, the trisomy 8 cells lost contact inhibition and reproliferated after exhibiting senescence-like characteristics that are typical of transformed cells. Furthermore, the trisomy 8 cells exhibited chromosome instability, and the overall gene expression profile based on microarray analyses was significantly different from that of diploid human primary fibroblasts. Our data suggest that aneuploidy, even a single chromosome gain, can be introduced into normal human cells and causes, in some cases, a partial cancer phenotype due to a disruption in overall gene expression.

  6. Stem Cell Therapies for Treating Diabetes: Progress and Remaining Challenges.

    Science.gov (United States)

    Sneddon, Julie B; Tang, Qizhi; Stock, Peter; Bluestone, Jeffrey A; Roy, Shuvo; Desai, Tejal; Hebrok, Matthias

    2018-06-01

    Restoration of insulin independence and normoglycemia has been the overarching goal in diabetes research and therapy. While whole-organ and islet transplantation have become gold-standard procedures in achieving glucose control in diabetic patients, the profound lack of suitable donor tissues severely hampers the broad application of these therapies. Here, we describe current efforts aimed at generating a sustainable source of functional human stem cell-derived insulin-producing islet cells for cell transplantation and present state-of-the-art efforts to protect such cells via immune modulation and encapsulation strategies. Copyright © 2018. Published by Elsevier Inc.

  7. 78 FR 66621 - Protection of Collateral of Counterparties to Uncleared Swaps; Treatment of Securities in a...

    Science.gov (United States)

    2013-11-06

    ... or MSP may not have that information. \\45\\ Several commenters highlighted the importance of have the... Swaps Customer Account constitute ``customer property''; and owners of such account constitute ``customers.'' DATES: Effective date: This rule is effective January 6, 2014. Compliance dates: For uncleared...

  8. Impact of in vitro treatments of physiological levels of estradiol and progesterone observed in pregnancy on bovine monocyte-derived dendritic cell differentiation and maturation

    NARCIS (Netherlands)

    Pomeroy, Brianna; Klaessig, Suzanne; Schukken, Ynte

    2016-01-01

    The specific factors which regulate differentiation and maturation of dendritic cells in bovine pregnancy remain unclear. We evaluated the influence of physiologically relevant in vitro treatments of progesterone (PG) and estradiol (E2) observed in late pregnancy on the differentiation and

  9. Interpreting heterogeneity in intestinal tuft cell structure and function.

    Science.gov (United States)

    Banerjee, Amrita; McKinley, Eliot T; von Moltke, Jakob; Coffey, Robert J; Lau, Ken S

    2018-05-01

    Intestinal tuft cells are a morphologically unique cell type, best characterized by striking microvilli that form an apical tuft. These cells represent approximately 0.5% of gut epithelial cells depending on location. While they are known to express chemosensory receptors, their function has remained unclear. Recently, numerous groups have revealed startling insights into intestinal tuft cell biology. Here, we review the latest developments in understanding this peculiar cell type's structure and function. Recent advances in volumetric microscopy have begun to elucidate tuft cell ultrastructure with respect to its cellular neighbors. Moreover, single-cell approaches have revealed greater diversity in the tuft cell population than previously appreciated and uncovered novel markers to characterize this heterogeneity. Finally, advanced model systems have revealed tuft cells' roles in mucosal healing and orchestrating type 2 immunity against eukaryotic infection. While much remains unknown about intestinal tuft cells, these critical advances have illuminated the physiological importance of these previously understudied cells and provided experimentally tractable tools to interrogate this rare cell population. Tuft cells act as luminal sensors, linking the luminal microbiome to the host immune system, which may make them a potent clinical target for modulating host response to a variety of acute or chronic immune-driven conditions.

  10. Glucocorticoids induce autophagy in rat bone marrow mesenchymal stem cells

    DEFF Research Database (Denmark)

    Wang, L.; Fan, J.; Lin, Y. S.

    2015-01-01

    Glucocorticoidinduced osteoporosis (GIOP) is a widespread clinical complication following glucocorticoid therapy. This irreversible damage to boneforming and resorbing cells is essential in the pathogenesis of osteoporosis. Autophagy is a physiological process involved in the regulation of cells...... and their responses to diverse stimuli, however, the role of autophagy in glucocorticoidinduced damage to bone marrow mesenchymal stem cells (BMSCs) remains unclear. The current study confirmed that glucocorticoid administration impaired the proliferation of BMSCs. Transmission electron microscopy...... that in response to glucocorticoid administration, induced autophagy aids to maintain proliferation and prevent apoptosis of BMSCs. Thus, it is hypothesized that autophagy may be a novel target in the treatment or prevention of osteoporosis....

  11. Forced freedom. Part 6. The large-scale consumer. Natural gas trade laborious en unclear

    International Nuclear Information System (INIS)

    Kop, L.

    2001-01-01

    Many organisations are busy taking care of their natural gas purchase. Data are compiled, profiles studied, and possibilities for peak shaving examined. Because of the unknown subject, many companies consult specialised advisers. All in all a lot of work, the more so while much is still unclear. One good advice is to ask the VEMW, a Dutch association for the industrial users of energy, environment and water. VEMW has insight into market prices and related conditions

  12. Hypoxic Preconditioning Promotes the Bioactivities of Mesenchymal Stem Cells via the HIF-1?-GRP78-Akt Axis

    OpenAIRE

    Lee, Jun Hee; Yoon, Yeo Min; Lee, Sang Hun

    2017-01-01

    Mesenchymal stem cells (MSC) are ideal materials for stem cell-based therapy. As MSCs reside in hypoxic microenvironments (low oxygen tension of 1% to 7%), several studies have focused on the beneficial effects of hypoxic preconditioning on MSC survival; however, the mechanisms underlying such effects remain unclear. This study aimed to uncover the potential mechanism involving 78-kDa glucose-regulated protein (GRP78) to explain the enhanced MSC bioactivity and survival in hindlimb ischemia. ...

  13. Impact of in vitro treatments of physiological levels of estradiol and progesterone observed in pregnancy on bovine monocyte-derived dendritic cell differentiation and maturation

    NARCIS (Netherlands)

    Pomeroy, Brianna; Klaessig, Suzanne; Schukken, Ynte

    2016-01-01

    The specific factors which regulate differentiation and maturation of dendritic cells in bovine pregnancy remain unclear. We evaluated the influence of physiologically relevant in vitro treatments of progesterone (PG) and estradiol (E2) observed in late pregnancy on the differentiation and

  14. The kinetic alteration of hematopoietic stem cells irradiated by ionizing radiation

    International Nuclear Information System (INIS)

    Ishikawa, Junya; Ojima, Mitsuaki; Kai, Michiaki

    2014-01-01

    Ionizing radiation (IR) brings oxidative stress, and can cause damages not only on DNA but also proteins and lipids in mammalian cells, and increases the mitochondria-dependent generation of reactive oxygen species (ROS), with the subsequent induction of cell death, cell cycle arrest, and stress related responses. It is well known that IR induces acute myeloid leukemia that originates in hematopoietic cells. However, the mechanisms of leukemogenesis following IR remain unclear. To clarify these mechanisms, it is necessary to quantify the several biological events induced by IR in hematopoietic stem/progenitor cells. In this review, we focus and summarize several recent findings, especially survival/clonogenic potential, cell cycle distribution, generation of ROS, DNA damage/repair, chromosomal abbreviation, and senescence. (author)

  15. 6-Thioguanine Reactivates Epigenetically Silenced Genes in Acute Lymphoblastic Leukemia Cells by Facilitating Proteasome-mediated Degradation of DNMT1

    OpenAIRE

    Yuan, Bifeng; Zhang, Jing; Wang, Hongxia; Xiong, Lei; Cai, Qian; Wang, Tina; Jacobsen, Steven; Pradhan, Sriharsa; Wang, Yinsheng

    2011-01-01

    Thiopurines including 6-thioguanine (SG), 6-mercaptopurine and azathioprine are effective anticancer agents with remarkable success in clinical practice, especially in effective treatment of acute lymphoblastic leukemia (ALL). SG is understood to act as a DNA hypomethylating agent in ALL cells, however, the underlying mechanism leading to global cytosine demethylation remains unclear. Here we report that SG treatment results in reactivation of epigenetically silenced genes in T leukemia cells...

  16. Modeling Human Natural Killer Cell Development in the Era of Innate Lymphoid Cells.

    Science.gov (United States)

    Scoville, Steven D; Freud, Aharon G; Caligiuri, Michael A

    2017-01-01

    Decades after the discovery of natural killer (NK) cells, their developmental pathways in mice and humans have not yet been completely deciphered. Accumulating evidence indicates that NK cells can develop in multiple tissues throughout the body. Moreover, detailed and comprehensive models of NK cell development were proposed soon after the turn of the century. However, with the recent identification and characterization of other subtypes of innate lymphoid cells (ILCs), which show some overlapping functional and phenotypic features with NK cell developmental intermediates, the distinct stages through which human NK cells develop from early hematopoietic progenitor cells remain unclear. Thus, there is a need to reassess and refine older models of NK cell development in the context of new data and in the era of ILCs. Our group has focused on elucidating the developmental pathway of human NK cells in secondary lymphoid tissues (SLTs), including tonsils and lymph nodes. Here, we provide an update of recent progress that has been made with regard to human NK cell development in SLTs, and we discuss these new findings in the context of contemporary models of ILC development.

  17. Impaired Autophagy and Defective T Cell Homeostasis in Mice with T Cell-Specific Deletion of Receptor for Activated C Kinase 1

    Directory of Open Access Journals (Sweden)

    Guihua Qiu

    2017-05-01

    Full Text Available Autophagy plays a central role in maintaining T cell homeostasis. Our previous study has shown that hepatocyte-specific deficiency of receptor for activated C kinase 1 (RACK1 leads to lipid accumulation in the liver, accompanied by impaired autophagy, but its in vivo role in T cells remains unclear. Here, we report that mice with T cell-specific deletion of RACK1 exhibit normal intrathymic development of conventional T cells and regulatory T (Treg cells but reduced numbers of peripheral CD4+ and CD8+ T cells. Such defects are cell intrinsic with impaired mitochondrial clearance, increased sensitivity to cell death, and decreased proliferation that could be explained by impaired autophagy. Furthermore, RACK1 is essential for invariant natural T cell development. In vivo, T cell-specific loss of RACK1 dampens concanavalin A-induced acute liver injury. Our data suggest that RACK1 is a key regulator of T cell homeostasis.

  18. Cell shape regulates global histone acetylation in human mammaryepithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Le Beyec, Johanne; Xu, Ren; Lee, Sun-Young; Nelson, Celeste M.; Rizki, Aylin; Alcaraz, Jordi; Bissell, Mina J.

    2007-02-28

    Extracellular matrix (ECM) regulates cell morphology and gene expression in vivo; these relationships are maintained in three-dimensional (3D) cultures of mammary epithelial cells. In the presence of laminin-rich ECM (lrECM), mammary epithelial cells round up and undergo global histone deacetylation, a process critical for their functional differentiation. However, it remains unclear whether lrECM-dependent cell rounding and global histone deacetylation are indeed part of a common physical-biochemical pathway. Using 3D cultures as well as nonadhesive and micropatterned substrata, here we showed that the cell 'rounding' caused by lrECM was sufficient to induce deacetylation of histones H3 and H4 in the absence of biochemical cues. Microarray and confocal analysis demonstrated that this deacetylation in 3D culture is associated with a global increase in chromatin condensation and a reduction in gene expression. Whereas cells cultured on plastic substrata formed prominent stress fibers, cells grown in 3D lrECM or on micropatterns lacked these structures. Disruption of the actin cytoskeleton with cytochalasin D phenocopied the lrECM-induced cell rounding and histone deacetylation. These results reveal a novel link between ECM-controlled cell shape and chromatin structure, and suggest that this link is mediated by changes in the actin cytoskeleton.

  19. Stem cell identity and template DNA strand segregation.

    Science.gov (United States)

    Tajbakhsh, Shahragim

    2008-12-01

    The quest for stem cell properties to distinguish their identity from that of committed daughters has led to a re-investigation of the notion that DNA strands are not equivalent, and 'immortal' DNA strands are retained in stem cells whereas newly replicated DNA strands segregate to the differentiating daughter cell during mitosis. Whether this process occurs only in stem cells, and also in all tissues, remains unclear. That individual chromosomes can be also partitioned non-randomly raises the question if this phenomenon is related to the immortal DNA hypothesis, and it underscores the need for high-resolution techniques to observe these events empirically. Although initially postulated as a mechanism to avoid DNA replication errors, alternative views including epigenetic regulation and sister chromatid silencing may provide insights into this process.

  20. The PSA−/lo prostate cancer cell population harbors self-renewing long-term tumor-propagating cells that resist castration

    Science.gov (United States)

    Qin, Jichao; Liu, Xin; Laffin, Brian; Chen, Xin; Choy, Grace; Jeter, Collene; Calhoun-Davis, Tammy; Li, Hangwen; Palapattu, Ganesh S.; Pang, Shen; Lin, Kevin; Huang, Jiaoti; Ivanov, Ivan; Li, Wei; Suraneni, Mahipal V.; Tang, Dean G.

    2012-01-01

    SUMMARY Prostate cancer (PCa) is heterogeneous and contains both differentiated and undifferentiated tumor cells, but the relative functional contribution of these two cell populations remains unclear. Here we report distinct molecular, cellular, and tumor-propagating properties of PCa cells that express high (PSA+) and low (PSA−/lo) levels of the differentiation marker PSA. PSA−/lo PCa cells are quiescent and refractory to stresses including androgen deprivation, exhibit high clonogenic potential, and possess long-term tumor-propagating capacity. They preferentially express stem cell genes and can undergo asymmetric cell division generating PSA+ cells. Importantly, PSA−/lo PCa cells can initiate robust tumor development and resist androgen ablation in castrated hosts, and harbor highly tumorigenic castration-resistant PCa cells that can be prospectively enriched using ALDH+CD44+α2β1+ phenotype. In contrast, PSA+ PCa cells possess more limited tumor-propagating capacity, undergo symmetric division and are sensitive to castration. Together, our study suggests PSA−/lo cells may represent a critical source of castration-resistant PCa cells. PMID:22560078

  1. Is this the end of cytotoxic chemotherapy in Merkel cell carcinoma?

    Directory of Open Access Journals (Sweden)

    Rabinowits G

    2017-09-01

    Full Text Available Guilherme Rabinowits Department of Medical Oncology, Center for Head and Neck Oncology, Dana-Farber Cancer Institute, Boston, MA, USA Abstract: Although cytotoxic chemotherapy has been used often in the management of Merkel cell carcinoma (MCC, its benefit remains uncertain. Despite being considered a chemosensitive disease, the duration of response is generally short, and the survival benefit is unclear. With the recent FDA approval of the anti-programmed cell death ligand 1 (PD-L1 antibody avelumab for patients with advanced MCC and the limited and controversial data on chemotherapy, it is important to put in perspective whether conventional chemotherapy should remain an option for these patients. Here, we review the evidence and controversies around chemotherapy in MCC as well as two recent studies on immunotherapy that changed the treatment paradigm for this disease. Keywords: Merkel cell carcinoma, chemotherapy, immunotherapy, review, future

  2. Epigenetic alterations of the SERPINE1 gene in oral squamous cell carcinomas and normal oral mucosa

    DEFF Research Database (Denmark)

    Gao, Shan; Nielsen, Boye Schnack; Krogdahl, Annelise

    2010-01-01

    cells in oral carcinomas by immunohistochemistry, we found that PAI-1 was expressed in 18 of the 20 patients, mainly by cancer cells. Two showed PAI-1 positive stromal cells surrounding the tumor areas and five showed PAI-1 positive cells in tumor-adjacent normal epithelium. By real-time RT-PCR analysis......A high level of plasminogen activator inhibitor-1 (PAI-1 or SERPINE1) in tumor extracts is a marker of a poor prognosis in human cancers, including oral carcinomas. However, the mechanisms responsible for the upregulation of PAI-1 in cancers remain unclear. Investigating specific PAI-1 expressing...

  3. Quantitative glycomics monitoring of induced pluripotent- and embryonic stem cells during neuronal differentiation

    Directory of Open Access Journals (Sweden)

    Michiyo Terashima

    2014-11-01

    Full Text Available Alterations in the structure of cell surface glycoforms occurring during the stages of stem cell differentiation remain unclear. We describe a rapid glycoblotting-based cellular glycomics method for quantitatively evaluating changes in glycoform expression and structure during neuronal differentiation of murine induced pluripotent stem cells (iPSCs and embryonic stem cells (ESCs. Our results show that changes in the expression of cellular N-glycans are comparable during the differentiation of iPSCs and ESCs. The expression of bisect-type N-glycans was significantly up-regulated in neurons that differentiated from both iPSCs and ESCs. From a glycobiological standpoint, iPSCs are an alternative neural cell source in addition to ESCs.

  4. Genetically induced cell death in bulge stem cells reveals their redundancy for hair and epidermal regeneration.

    Science.gov (United States)

    Driskell, Iwona; Oeztuerk-Winder, Feride; Humphreys, Peter; Frye, Michaela

    2015-03-01

    Adult mammalian epidermis contains multiple stem cell populations in which quiescent and more proliferative stem and progenitor populations coexist. However, the precise interrelation of these populations in homeostasis remains unclear. Here, we blocked the contribution of quiescent keratin 19 (K19)-expressing bulge stem cells to hair follicle formation through genetic ablation of the essential histone methyltransferase Setd8 that is required for the maintenance of adult skin. Deletion of Setd8 eliminated the contribution of bulge cells to hair follicle regeneration through inhibition of cell division and induction of cell death, but the growth and morphology of hair follicles were unaffected. Furthermore, ablation of Setd8 in the hair follicle bulge blocked the contribution of K19-postive stem cells to wounded epidermis, but the wound healing process was unaltered. Our data indicate that quiescent bulge stem cells are dispensable for hair follicle regeneration and epidermal injury in the short term and support the hypothesis that quiescent and cycling stem cell populations are equipotent. © 2014 AlphaMed Press.

  5. W/kit gene required for interstitial cells of Cajal and for intestinal pacemaker activity

    DEFF Research Database (Denmark)

    Huizinga, J D; Thuneberg, L; Klüppel, M

    1995-01-01

    The pacemaker activity in the mammalian gut is responsible for generating anally propagating phasic contractions. The cellular basis for this intrinsic activity is unknown. The smooth muscle cells of the external muscle layers and the innervated cellular network of interstitial cells of Cajal......, which is closely associated with the external muscle layers of the mammalian gut, have both been proposed to stimulate pacemaker activity. The interstitial cells of Cajal were identified in the last century but their developmental origin and function have remained unclear. Here we show...... of Cajal associated with Auerbach's nerve plexus and intestinal pacemaker activity....

  6. The neural crest is a source of mesenchymal stem cells with specialized hematopoietic stem cell niche function.

    Science.gov (United States)

    Isern, Joan; García-García, Andrés; Martín, Ana M; Arranz, Lorena; Martín-Pérez, Daniel; Torroja, Carlos; Sánchez-Cabo, Fátima; Méndez-Ferrer, Simón

    2014-09-25

    Mesenchymal stem cells (MSCs) and osteolineage cells contribute to the hematopoietic stem cell (HSC) niche in the bone marrow of long bones. However, their developmental relationships remain unclear. In this study, we demonstrate that different MSC populations in the developing marrow of long bones have distinct functions. Proliferative mesoderm-derived nestin(-) MSCs participate in fetal skeletogenesis and lose MSC activity soon after birth. In contrast, quiescent neural crest-derived nestin(+) cells preserve MSC activity, but do not generate fetal chondrocytes. Instead, they differentiate into HSC niche-forming MSCs, helping to establish the HSC niche by secreting Cxcl12. Perineural migration of these cells to the bone marrow requires the ErbB3 receptor. The neonatal Nestin-GFP(+) Pdgfrα(-) cell population also contains Schwann cell precursors, but does not comprise mature Schwann cells. Thus, in the developing bone marrow HSC niche-forming MSCs share a common origin with sympathetic peripheral neurons and glial cells, and ontogenically distinct MSCs have non-overlapping functions in endochondrogenesis and HSC niche formation.

  7. Cell division orientation is coupled to cell-cell adhesion by the E-cadherin/LGN complex

    NARCIS (Netherlands)

    Gloerich, Martijn; Bianchini, Julie M.; Siemers, Kathleen A.; Cohen, Daniel J.; Nelson, W. James

    2017-01-01

    Both cell-cell adhesion and oriented cell division play prominent roles in establishing tissue architecture, but it is unclear how they might be coordinated. Here, we demonstrate that the cell-cell adhesion protein E-cadherin functions as an instructive cue for cell division orientation. This is

  8. Role of cell death in the propagation of PrP(Sc) in immune cells.

    Science.gov (United States)

    Takahashi, Kenichi; Inoshima, Yasuo; Ishiguro, Naotaka

    2015-03-01

    A number of studies have suggested that macrophages, dendritic cells, and follicular dendritic cells play an important role in the propagation of PrP(Sc). Both accumulation and proteolysis of PrP(Sc) have been demonstrated in peripheral macrophages. Macrophages may act as reservoirs for PrP(Sc) particles if the cells die during transient PrP(Sc) propagation. However, whether cell death plays a role in PrP(Sc) propagation in macrophages remains unclear. In this study, we investigated the possibility of propagation and transmission of PrP(Sc) between dead immune cells and living neural cells. We found that under specific conditions, transient PrP(Sc) propagation occurs in dead cells, indicating that interaction between PrP(C) and PrP(Sc) on plasma membrane lipid rafts might be important for PrP(Sc) propagation. Co-culturing of killed donor PrP(Sc)-infected macrophages with recipient N2a-3 neuroblastoma cells accelerated PrP(Sc) transmission. Our results suggest that cell death may play an important role in PrP(Sc) propagation, whereas transient PrP(Sc) propagation in macrophages has little effect on PrP(Sc) transmission.

  9. Influence of Mesenchymal Stem Cells Conditioned Media on Proliferation of Urinary Tract Cancer Cell Lines and Their Sensitivity to Ciprofloxacin.

    Science.gov (United States)

    Maj, Malgorzata; Bajek, Anna; Nalejska, Ewelina; Porowinska, Dorota; Kloskowski, Tomasz; Gackowska, Lidia; Drewa, Tomasz

    2017-06-01

    Mesenchymal stem cells (MSCs) are known to interact with cancer cells through direct cell-to-cell contact and secretion of paracrine factors, although their exact influence on tumor progression in vivo remains unclear. To better understand how fetal and adult stem cells affect tumors, we analyzed viability of human renal (786-0) and bladder (T24) carcinoma cell lines cultured in conditioned media harvested from amniotic fluid-derived stem cells (AFSCs) and adipose-derived stem cells (ASCs). Both media reduced metabolic activity of 786-0 cells, however, decreased viability of T24 cells was noted only after incubation with conditioned medium from ASCs. To test the hypothesis that MSCs-secreted factors might be involved in chemoresistance acquisition, we further analyzed influence of mesenchymal stem cell conditioned media (MSC-CM) on cancer cells sensitivity to ciprofloxacin, that is considered as potential candidate agent for urinary tract cancers treatment. Significantly increased resistance to tested drug indicates that MSCs may protect cancer cells from chemotherapy. J. Cell. Biochem. 118: 1361-1368, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Predictors of trend in CD4-positive T-cell count and mortality among HIV-1-infected individuals with virological failure to all three antiretroviral-drug classes

    DEFF Research Database (Denmark)

    Ledergerber, Bruno; Lundgren, Jens D; Walker, A Sarah

    2014-01-01

    Treatment strategies for patients in whom HIV replication is not suppressed after exposure to several drug classes remain unclear. We aimed to assess the inter-relations between viral load, CD4-cell count, and clinical outcome in patients who had experienced three-class virological failure....

  11. Secretin receptor involvement in prion-infected cells and animals.

    Science.gov (United States)

    Kimura, Tomohiro; Nishizawa, Keiko; Oguma, Ayumi; Nishimura, Yuki; Sakasegawa, Yuji; Teruya, Kenta; Nishijima, Ichiko; Doh-ura, Katsumi

    2015-07-08

    The cellular mechanisms behind prion biosynthesis and metabolism remain unclear. Here we show that secretin signaling via the secretin receptor regulates abnormal prion protein formation in prion-infected cells. Animal studies demonstrate that secretin receptor deficiency slightly, but significantly, prolongs incubation time in female but not male mice. This gender-specificity is consistent with our finding that prion-infected cells are derived from females. Therefore, our results provide initial insights into the reasons why age of disease onset in certain prion diseases is reported to occur slightly earlier in females than males. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  12. Functional heterogeneity of side population cells in skeletal muscle

    International Nuclear Information System (INIS)

    Uezumi, Akiyoshi; Ojima, Koichi; Fukada, So-ichiro; Ikemoto, Madoka; Masuda, Satoru; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi

    2006-01-01

    Skeletal muscle regeneration has been exclusively attributed to myogenic precursors, satellite cells. A stem cell-rich fraction referred to as side population (SP) cells also resides in skeletal muscle, but its roles in muscle regeneration remain unclear. We found that muscle SP cells could be subdivided into three sub-fractions using CD31 and CD45 markers. The majority of SP cells in normal non-regenerating muscle expressed CD31 and had endothelial characteristics. However, CD31 - CD45 - SP cells, which are a minor subpopulation in normal muscle, actively proliferated upon muscle injury and expressed not only several regulatory genes for muscle regeneration but also some mesenchymal lineage markers. CD31 - CD45 - SP cells showed the greatest myogenic potential among three SP sub-fractions, but indeed revealed mesenchymal potentials in vitro. These SP cells preferentially differentiated into myofibers after intramuscular transplantation in vivo. Our results revealed the heterogeneity of muscle SP cells and suggest that CD31 - CD45 - SP cells participate in muscle regeneration

  13. Cell migration induced by Leishmania (Leishmania) amazonensis, Leishmania (Leishmania) major and Leishmania (Viannia) braziliensis into the peritoneal cavity of BALB/c mice

    OpenAIRE

    DT Wakimoto; KV Gaspareto; TGV Silveira; MVC Lonardoni; SMA Aristides

    2010-01-01

    In American cutaneous leishmaniasis, the initial infection phase is characterized by recruitment of neutrophils and monocytes. The migration of these cells in response to the presence of Leishmania in the peritoneum of affected animals remains unclear. The objective of this study was to investigate cell migration to the peritoneum of BALB/c mice after infection with Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis and Leishmania (Leishmania) major. Initially, Leishmania ...

  14. The E-Id Protein Axis Specifies Adaptive Lymphoid Cell Identity and Suppresses Thymic Innate Lymphoid Cell Development.

    Science.gov (United States)

    Miyazaki, Masaki; Miyazaki, Kazuko; Chen, Kenian; Jin, Yi; Turner, Jacob; Moore, Amanda J; Saito, Rintaro; Yoshida, Kenichi; Ogawa, Seishi; Rodewald, Hans-Reimer; Lin, Yin C; Kawamoto, Hiroshi; Murre, Cornelis

    2017-05-16

    Innate and adaptive lymphoid development is orchestrated by the activities of E proteins and their antagonist Id proteins, but how these factors regulate early T cell progenitor (ETP) and innate lymphoid cell (ILC) development remains unclear. Using multiple genetic strategies, we demonstrated that E proteins E2A and HEB acted in synergy in the thymus to establish T cell identity and to suppress the aberrant development of ILCs, including ILC2s and lymphoid-tissue-inducer-like cells. E2A and HEB orchestrated T cell fate and suppressed the ILC transcription signature by activating the expression of genes associated with Notch receptors, T cell receptor (TCR) assembly, and TCR-mediated signaling. E2A and HEB acted in ETPs to establish and maintain a T-cell-lineage-specific enhancer repertoire, including regulatory elements associated with the Notch1, Rag1, and Rag2 loci. On the basis of these and previous observations, we propose that the E-Id protein axis specifies innate and adaptive lymphoid cell fate. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. NKG2H-Expressing T Cells Negatively Regulate Immune Responses

    Directory of Open Access Journals (Sweden)

    Daniela Dukovska

    2018-03-01

    Full Text Available The biology and function of NKG2H receptor, unlike the better characterized members of the NKG2 family NKG2A, NKG2C, and NKG2D, remains largely unclear. Here, we show that NKG2H is able to associate with the signaling adapter molecules DAP12 and DAP10 suggesting that this receptor can signal for cell activation. Using a recently described NKG2H-specific monoclonal antibody (mAb, we have characterized the expression and function of lymphocytes that express this receptor. NKG2H is expressed at the cell surface of a small percentage of peripheral blood mononuclear cell (PBMC and is found more frequently on T cells, rather than NK cells. Moreover, although NKG2H is likely to trigger activation, co-cross-linking of this receptor with an NKG2H-specific mAb led to decreased T cell activation and proliferation in polyclonal PBMC cultures stimulated by anti-CD3 mAbs. This negative regulatory activity was seen only after cross-linking with NKG2H, but not NKG2A- or NKG2C-specific monoclonal antibodies. The mechanism underlying this negative effect is as yet unclear, but did not depend on the release of soluble factors or recognition of MHC class I molecules. These observations raise the intriguing possibility that NKG2H may be a novel marker for T cells able to negatively regulate T cell responses.

  16. Premature aging/senescence in cancer cells facing therapy: good or bad?

    Science.gov (United States)

    Gonzalez, Llilians Calvo; Ghadaouia, Sabrina; Martinez, Aurélie; Rodier, Francis

    2016-02-01

    Normal and cancer cells facing their demise following exposure to radio-chemotherapy can actively participate in choosing their subsequent fate. These programmed cell fate decisions include true cell death (apoptosis-necroptosis) and therapy-induced cellular senescence (TIS), a permanent "proliferative arrest" commonly portrayed as premature cellular aging. Despite a permanent loss of proliferative potential, senescent cells remain viable and are highly bioactive at the microenvironment level, resulting in a prolonged impact on tissue architecture and functions. Cellular senescence is primarily documented as a tumor suppression mechanism that prevents cellular transformation. In the context of normal tissues, cellular senescence also plays important roles in tissue repair, but contributes to age-associated tissue dysfunction when senescent cells accumulate. Theoretically, in multi-step cancer progression models, cancer cells have already bypassed cellular senescence during their immortalization step (see hallmarks of cancer). It is then perhaps surprising to find that cancer cells often retain the ability to undergo TIS, or premature aging. This occurs because cellular senescence results from multiple signalling pathways, some retained in cancer cells, aiming to prevent cell cycle progression in damaged cells. Since senescent cancer cells persist after therapy and secrete an array of cytokines and growth factors that can modulate the tumor microenvironment, these cells may have beneficial and detrimental effects regarding immune modulation and survival of remaining proliferation-competent cancer cells. Similarly, while normal cells undergoing senescence are believed to remain indefinitely growth arrested, whether this is true for senescent cancer cells remains unclear, raising the possibility that these cells may represent a reservoir for cancer recurrence after treatment. This review discusses our current knowledge on cancer cell senescence and highlight questions

  17. Ezrin dephosphorylation/downregulation contributes to ursolic acid-mediated cell death in human leukemia cells

    International Nuclear Information System (INIS)

    Li, G; Zhou, T; Liu, L; Chen, J; Zhao, Z; Peng, Y; Li, P; Gao, N

    2013-01-01

    Ezrin links the actin filaments with the cell membrane and has a functional role in the apoptotic process. It appears clear that ezrin is directly associated with Fas, leading to activation of caspase cascade and cell death. However, the exact role of ezrin in ursolic acid (UA)-induced apoptosis remains unclear. In this study, we show for the first time that UA induces apoptosis in both transformed and primary leukemia cells through dephosphorylation/downregulation of ezrin, association and polarized colocalization of Fas and ezrin, as well as formation of death-inducing signaling complex. These events are dependent on Rho-ROCK1 signaling pathway. Knockdown of ezrin enhanced cell death mediated by UA, whereas overexpression of ezrin attenuated UA-induced apoptosis. Our in vivo study also showed that UA-mediated inhibition of tumor growth of mouse leukemia xenograft model is in association with the dephosphorylation/downregulation of ezrin. Such findings suggest that the cytoskeletal protein ezrin may represent an attractive target for UA-mediated lethality in human leukemia cells

  18. Oncogenic ras-driven cancer cell vesiculation leads to emission of double-stranded DNA capable of interacting with target cells

    International Nuclear Information System (INIS)

    Lee, Tae Hoon; Chennakrishnaiah, Shilpa; Audemard, Eric; Montermini, Laura; Meehan, Brian; Rak, Janusz

    2014-01-01

    Highlights: • Oncogenic H-ras stimulates emission of extracellular vesicles containing double-stranded DNA. • Vesicle-associated extracellular DNA contains mutant N-ras sequences. • Vesicles mediate intercellular transfer of mutant H-ras DNA to normal fibroblasts where it remains for several weeks. • Fibroblasts exposed to vesicles containing H-ras DNA exhibit increased proliferation. - Abstract: Cell free DNA is often regarded as a source of genetic cancer biomarkers, but the related mechanisms of DNA release, composition and biological activity remain unclear. Here we show that rat epithelial cell transformation by the human H-ras oncogene leads to an increase in production of small, exosomal-like extracellular vesicles by viable cancer cells. These EVs contain chromatin-associated double-stranded DNA fragments covering the entire host genome, including full-length H-ras. Oncogenic N-ras and SV40LT sequences were also found in EVs emitted from spontaneous mouse brain tumor cells. Disruption of acidic sphingomyelinase and the p53/Rb pathway did not block emission of EV-related oncogenic DNA. Exposure of non-transformed RAT-1 cells to EVs containing mutant H-ras DNA led to the uptake and retention of this material for an extended (30 days) but transient period of time, and stimulated cell proliferation. Thus, our study suggests that H-ras-mediated transformation stimulates vesicular emission of this histone-bound oncogene, which may interact with non-transformed cells

  19. Oncogenic ras-driven cancer cell vesiculation leads to emission of double-stranded DNA capable of interacting with target cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tae Hoon; Chennakrishnaiah, Shilpa [Montreal Children’s Hospital, Research Institute of McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Audemard, Eric [McGill University and Genome Quebec Innovation Centre, Montreal, Quebec (Canada); Montermini, Laura; Meehan, Brian [Montreal Children’s Hospital, Research Institute of McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Rak, Janusz, E-mail: janusz.rak@mcgill.ca [Montreal Children’s Hospital, Research Institute of McGill University Health Centre, McGill University, Montreal, Quebec (Canada)

    2014-08-22

    Highlights: • Oncogenic H-ras stimulates emission of extracellular vesicles containing double-stranded DNA. • Vesicle-associated extracellular DNA contains mutant N-ras sequences. • Vesicles mediate intercellular transfer of mutant H-ras DNA to normal fibroblasts where it remains for several weeks. • Fibroblasts exposed to vesicles containing H-ras DNA exhibit increased proliferation. - Abstract: Cell free DNA is often regarded as a source of genetic cancer biomarkers, but the related mechanisms of DNA release, composition and biological activity remain unclear. Here we show that rat epithelial cell transformation by the human H-ras oncogene leads to an increase in production of small, exosomal-like extracellular vesicles by viable cancer cells. These EVs contain chromatin-associated double-stranded DNA fragments covering the entire host genome, including full-length H-ras. Oncogenic N-ras and SV40LT sequences were also found in EVs emitted from spontaneous mouse brain tumor cells. Disruption of acidic sphingomyelinase and the p53/Rb pathway did not block emission of EV-related oncogenic DNA. Exposure of non-transformed RAT-1 cells to EVs containing mutant H-ras DNA led to the uptake and retention of this material for an extended (30 days) but transient period of time, and stimulated cell proliferation. Thus, our study suggests that H-ras-mediated transformation stimulates vesicular emission of this histone-bound oncogene, which may interact with non-transformed cells.

  20. Parapoxvirus orf virus infection induces an increase in interleukin-8, tumour necrosis factor-α, and decorin in goat skin fibroblast cells

    Directory of Open Access Journals (Sweden)

    Wang Lingling

    2016-09-01

    Full Text Available Introduction: Orf virus (ORFV is a prototype Parapoxvirus species in the Poxviridae family that causes serious zoonotic infectious disease. Goat skin fibroblast (GSF cells are the major host targets of ORFV. Interleukin 8 (IL-8 and tumour necrosis factor (TNF-α are known to play a vital role in immune response during viral infections. However, the manner of variation over time of their level of expression in GSF cells remains unclear.

  1. Intrinsic and extrinsic contributors to defective CD8+ T cell responses with aging.

    Science.gov (United States)

    Jergović, Mladen; Smithey, Megan J; Nikolich-Žugich, Janko

    2018-05-01

    Aging has a profound effect on the immune system, and both innate and adaptive arms of the immune system show functional decline with age. In response to infection with intracellular microorganisms, old animals mobilize decreased numbers of antigen-specific CD8+ T cells with reduced production of effector molecules and impaired cytolytic activity. However, the CD8+ T cell-intrinsic contribution to, and molecular mechanisms behind, these defects remain unclear. In this review we will discuss the mechanistic contributions of age related changes in the CD8+ T cell pool and the relative roles of intrinsic functional defects in aged CD8+ T cells vs. defects in the aged environment initiating the CD8+ T cell response. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. CD301b⁺ dermal dendritic cells drive T helper 2 cell-mediated immunity.

    Science.gov (United States)

    Kumamoto, Yosuke; Linehan, Melissa; Weinstein, Jason S; Laidlaw, Brian J; Craft, Joseph E; Iwasaki, Akiko

    2013-10-17

    Unlike other types of T helper (Th) responses, whether the development of Th2 cells requires instruction from particular subset of dendritic cells (DCs) remains unclear. By using an in vivo depletion approach, we have shown that DCs expressing CD301b were required for the generation of Th2 cells after subcutaneous immunization with ovalbumin (OVA) along with papain or alum. CD301b⁺ DCs are distinct from epidermal or CD207⁺ dermal DCs (DDCs) and were responsible for transporting antigen injected subcutaneously with Th2-type adjuvants. Transient depletion of CD301b⁺ DCs resulted in less effective accumulation and decreased expression of CD69 by polyclonal CD4⁺ T cells in the lymph node. Moreover, despite intact cell division and interferon-γ production, CD301b⁺ DC depletion led to blunted interleukin-4 production by OVA-specific OT-II transgenic CD4⁺ T cells and significantly impaired Th2 cell development upon infection with Nippostrongylus brasiliensis. These results reveal CD301b⁺ DDCs as the key mediators of Th2 immunity. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Cell Morphological Change and Caspase-3 Protein Expression on Epithelial Cells under Stimulation of Oral Bacterium Streptococcus sanguinis

    Directory of Open Access Journals (Sweden)

    Suryani Hutomo

    2015-07-01

    Full Text Available Oral commensal bacterium Streptococcus sanguinis may find in periodontal lesions, deep seated infection, and infective endocarditis that are usually dominated by anaerobes. This bacterium caused cell death on some cells but host responses to this species remained unclear. Objective: This study was aimed to detect cell morphologica change and role of caspase-3 in cell death mechanism induced by S. sanguinis. Methods: HeLa cells as representative model for oral epithelial cells were exposed to 107 cells/ml bacteria for 48 h. Morphological change was observed microscopically after hematoxyline-eosin staining. Expression of active caspase-3 was examined by immunocytochemical analysis after cell stimulation for 36 and 48 h with wild type supragingival S. sanguinis. Doxorubicin (0.5625 μg/ml was used as positive control for caspase-3 activation. Results: The results showed cell shrinkage of bacterial-treated cells; and active caspase-3 molecules were detected after 36 and 48 hours cell stimulation. Conclusion: This study would suggest cell shrinkage and caspase-3-dependent apoptotic cell death induced by S. sanguinis.DOI: 10.14693/jdi.v22i1.375

  4. Remaining useful life assessment of lithium-ion batteries in implantable medical devices

    Science.gov (United States)

    Hu, Chao; Ye, Hui; Jain, Gaurav; Schmidt, Craig

    2018-01-01

    This paper presents a prognostic study on lithium-ion batteries in implantable medical devices, in which a hybrid data-driven/model-based method is employed for remaining useful life assessment. The method is developed on and evaluated against data from two sets of lithium-ion prismatic cells used in implantable applications exhibiting distinct fade performance: 1) eight cells from Medtronic, PLC whose rates of capacity fade appear to be stable and gradually decrease over a 10-year test duration; and 2) eight cells from Manufacturer X whose rates appear to be greater and show sharp increase after some period over a 1.8-year test duration. The hybrid method enables online prediction of remaining useful life for predictive maintenance/control. It consists of two modules: 1) a sparse Bayesian learning module (data-driven) for inferring capacity from charge-related features; and 2) a recursive Bayesian filtering module (model-based) for updating empirical capacity fade models and predicting remaining useful life. A generic particle filter is adopted to implement recursive Bayesian filtering for the cells from the first set, whose capacity fade behavior can be represented by a single fade model; a multiple model particle filter with fixed-lag smoothing is proposed for the cells from the second data set, whose capacity fade behavior switches between multiple fade models.

  5. Sublethal irradiation promotes invasiveness of neuroblastoma cells

    International Nuclear Information System (INIS)

    Schweigerer, Lothar; Rave-Fraenk, Margret; Schmidberger, Heinz; Hecht, Monica

    2005-01-01

    Neuroblastoma is the most frequent extracranial solid tumour of childhood. Despite multiple clinical efforts, clinical outcome has remained poor. Neuroblastoma is considered to be radiosensitive, but some clinical studies including the German trial NB90 failed to show a clinical benefit of radiation therapy. The mechanisms underlying this apparent discrepancy are still unclear. We have therefore investigated the effects of radiation on neuroblastoma cell behaviour in vitro. We show that sublethal doses of irradiation up-regulated the expression of the hepatocyte growth factor (HGF) and its receptor c-Met in some neuroblastoma cell lines. The increase in HGF/c-Met expression was correlated with enhanced invasiveness and activation of proteases degrading the extracellular matrix. Thus, irradiation at sublethal doses may promote the metastatic dissemination of neuroblastoma cells through activating the HGF/c-Met pathway and triggering matrix degradation

  6. Deconstructing stem cell population heterogeneity: Single-cell analysis and modeling approaches

    Science.gov (United States)

    Wu, Jincheng; Tzanakakis, Emmanuel S.

    2014-01-01

    Isogenic stem cell populations display cell-to-cell variations in a multitude of attributes including gene or protein expression, epigenetic state, morphology, proliferation and proclivity for differentiation. The origins of the observed heterogeneity and its roles in the maintenance of pluripotency and the lineage specification of stem cells remain unclear. Addressing pertinent questions will require the employment of single-cell analysis methods as traditional cell biochemical and biomolecular assays yield mostly population-average data. In addition to time-lapse microscopy and flow cytometry, recent advances in single-cell genomic, transcriptomic and proteomic profiling are reviewed. The application of multiple displacement amplification, next generation sequencing, mass cytometry and spectrometry to stem cell systems is expected to provide a wealth of information affording unprecedented levels of multiparametric characterization of cell ensembles under defined conditions promoting pluripotency or commitment. Establishing connections between single-cell analysis information and the observed phenotypes will also require suitable mathematical models. Stem cell self-renewal and differentiation are orchestrated by the coordinated regulation of subcellular, intercellular and niche-wide processes spanning multiple time scales. Here, we discuss different modeling approaches and challenges arising from their application to stem cell populations. Integrating single-cell analysis with computational methods will fill gaps in our knowledge about the functions of heterogeneity in stem cell physiology. This combination will also aid the rational design of efficient differentiation and reprogramming strategies as well as bioprocesses for the production of clinically valuable stem cell derivatives. PMID:24035899

  7. Cadmium induced oxidative stress in kidney epithelia cells

    DEFF Research Database (Denmark)

    Bjerregaard, Henning F.

    2007-01-01

    Cadmium (Cd) is an important industrial and environmental pollutant. In humans exposed to Cd via oral and/or pulmonary routes, the kidney is by far the primary organ affected adversely by Cd. It have been estimated that 7% of the human population may develop renal dysfunction from Cd exposure...... of generation of ROS in this pathway remains unclear.     The aim of the present study was to monitor, in real time, the rates of ROS generation to be able to directly determine their production dynamics in living cells in response to drugs. Initial studies were planed in to use 2,7-dichlorofluorescein...... production from mitochondria due to an increase in the intracellular calcium concentration. Visual inspection of cultured cells showed that the Cd induced destruction of the cell membrane after three hours was abolished when cells were pretreated with N-acetylcysteine or CCCP, indicating that ROS generation...

  8. FOXP3 renders activated human regulatory T cells resistant to restimulation-induced cell death by suppressing SAP expression.

    Science.gov (United States)

    Katz, Gil; Voss, Kelsey; Yan, Toria F; Kim, Yong Chan; Kortum, Robert L; Scott, David W; Snow, Andrew L

    2018-05-01

    Restimulation-induced cell death (RICD) is an apoptotic program that regulates effector T cell expansion, triggered by repeated stimulation through the T cell receptor (TCR) in the presence of interleukin-2 (IL-2). Although CD4 + regulatory T cells (Tregs) consume IL-2 and experience frequent TCR stimulation, they are highly resistant to RICD. Resistance in Tregs is dependent on the forkhead box P3 (FOXP3) transcription factor, although the mechanism remains unclear. T cells from patients with X-linked lymphoproliferative disease (XLP-1), that lack the adaptor molecule SLAM-associated protein (SAP), are also resistant to RICD. Here we demonstrate that normal Tregs express very low levels of SAP compared to conventional T cells. FOXP3 reduces SAP expression by directly binding to and repressing the SH2D1A (SAP) promoter. Indeed, ectopic SAP expression restores RICD sensitivity in human FOXP3 + Tregs. Our findings illuminate the mechanism behind FOXP3-mediated RICD resistance in Tregs, providing new insight into their long-term persistence. Published by Elsevier Inc.

  9. Sex Differences in Maturation of Human Embryonic Stem Cell-Derived β Cells in Mice.

    Science.gov (United States)

    Saber, Nelly; Bruin, Jennifer E; O'Dwyer, Shannon; Schuster, Hellen; Rezania, Alireza; Kieffer, Timothy J

    2018-04-01

    Pancreatic progenitors derived from human embryonic stem cells (hESCs) are now in clinical trials for insulin replacement in patients with type 1 diabetes. Animal studies indicate that pancreatic progenitor cells can mature into a mixed population of endocrine cells, including glucose-responsive β cells several months after implantion. However, it remains unclear how conditions in the recipient may influence the maturation and ultimately the function of these hESC-derived cells. Here, we investigated the effects of (1) pregnancy on the maturation of human stage 4 (S4) pancreatic progenitor cells and (2) the impact of host sex on both S4 cells and more mature stage 7 (S7) pancreatic endocrine cells implanted under the kidney capsule of immunodeficient SCID-beige mice. Pregnancy led to increased proliferation of endogenous pancreatic β cells, but did not appear to affect proliferation or maturation of S4 cells at midgestation. Interestingly, S4 and S7 cells both acquired glucose-stimulated C-peptide secretion in females before males. Moreover, S4 cells lowered fasting blood glucose levels in females sooner than in males, whereas the responses with S7 cells were similar. These data indicate that the host sex may impact the maturation of hESC-derived cells in vivo and that this effect can be minimized by more advanced differentiation of the cells before implantation.

  10. FPPS mediates TGF-β1-induced non-small cell lung cancer cell invasion and the EMT process via the RhoA/Rock1 pathway.

    Science.gov (United States)

    Lin, Lin; Li, Ming; Lin, Lei; Xu, Xiaolin; Jiang, Gening; Wu, Liang

    2018-02-05

    Farnesyl pyrophosphate synthase (FPPS), a key enzyme in the mevalonate pathway, was recently shown to play a role in cancer progression. However, its role in non-small cell lung cancer (NSCLC) metastasis and the underlying mechanism remain unclear. In this study, FPPS expression was significantly correlated with TNM stage, and metastasis. Inhibition or knockdown of FPPS blocked TGF-β1-induced cell invasion and epithelial-to-mesenchymal transition (EMT) process. FPPS expression of FPPS was induced by TGF-β1 and FPPS promoted cell invasion and EMT via the RhoA/Rock1 pathway. In conclusion, FPPS mediates TGF-β1-induced lung cancer cell invasion and EMT via the RhoA/Rock1 pathway. These findings suggest new treatment strategies to reduce mortality associated with metastasis in patients with NSCLC. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. The dynamics of T and B cells in lymph node during chronic HIV infection: TFH and HIV, unhappy dance partners?

    Directory of Open Access Journals (Sweden)

    Jung Joo Hong

    2016-11-01

    Full Text Available Although the dynamics of germinal center (GC formation, TFH cell recruitment to B cell follicles within lymphoid organs and changes of lymphoid tissue architecture in HIV/SIV infection have been documented, the underlying immunopathology remains unclear. Here, we summarize what is known regarding the kinetics of TFH cells and GC B cells during the course of infection as well as the potential immunopathological features associated with structural changes in the lymphoid compartment. This review also explores the implications cell dynamics in the formation and maintenance of viral reservoirs in hyperplastic follicles of secondary lymphoid organs before and after viral suppressive antiretroviral therapy.

  12. PTEN drives Th17 cell differentiation by preventing IL-2 production.

    Science.gov (United States)

    Kim, Hyeong Su; Jang, Sung Woong; Lee, Wonyong; Kim, Kiwan; Sohn, Hyogon; Hwang, Soo Seok; Lee, Gap Ryol

    2017-11-06

    T helper 17 (Th17) cells are a CD4 + T cell subset that produces IL-17A to mediate inflammation and autoimmunity. IL-2 inhibits Th17 cell differentiation. However, the mechanism by which IL-2 is suppressed during Th17 cell differentiation remains unclear. Here, we show that phosphatase and tensin homologue (PTEN) is a key factor that regulates Th17 cell differentiation by suppressing IL-2 production. Th17-specific Pten deletion ( Pten fl/fl Il17a cre ) impairs Th17 cell differentiation in vitro and ameliorated symptoms of experimental autoimmune encephalomyelitis (EAE), a model of Th17-mediated autoimmune disease. Mechanistically, Pten deficiency up-regulates IL-2 and phosphorylation of STAT5, but reduces STAT3 phosphorylation, thereby inhibiting Th17 cell differentiation. PTEN inhibitors block Th17 cell differentiation in vitro and in the EAE model. Thus, PTEN plays a key role in Th17 cell differentiation by blocking IL-2 expression. © 2017 Kim et al.

  13. Activation of natural killer T cells promotes M2 macrophage polarization in adipose tissue and improves systemic glucose tolerance via the IL-4/STAT6 signaling axis in obesity

    NARCIS (Netherlands)

    Ji, Yewei; Sun, Shengyi; Xu, Aimin; Yang, Liu; Bhargava, Prerna; Lam, Karen S.; Gao, Bin; Lee, Chih-Hao; Kersten, Sander; Qi, Ling

    2012-01-01

    Natural killer T (NKT) cells are important therapeutic targets in various disease models and under clinical trials for cancer patients. However, their function in obesity and type 2 diabetes remains unclear. Our data show that adipose tissues of both mice and humans contain a population of type-1

  14. Nrf2 mediates redox adaptation in NOX4-overexpressed non-small cell lung cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qipeng; Yao, Bei; Li, Ning; Ma, Lei; Deng, Yanchao; Yang, Yang; Zeng, Cheng; Yang, Zhicheng [Department of Clinical Pharmacy, School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006 (China); Liu, Bing, E-mail: liubing520@gdpu.edu.cn [Department of Clinical Pharmacy, School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006 (China); Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, Guangdong Pharmaceutical University, Guangzhou 510006 (China)

    2017-03-15

    The redox adaptation mechanisms in cancer cells are very complex and remain largely unclear. Our previous studies have confirmed that NADPH oxidase 4 (NOX4) is abundantly expressed in non-small cell lung cancer (NSCLC) and confers apoptosis resistance on NSCLC cells. However, the comprehensive mechanisms for NOX4-mediated oxidative resistance of cancer cells remain still undentified. The present study found that NOX4-derived H{sub 2}O{sub 2} enhanced the nuclear factor erythroid 2-related factor 2 (Nrf2) stability via disruption of redox-dependent proteasomal degradation and stimulated its activity through activation of PI3K signaling. Specifically, the results showed that ectopic NOX4 expression did not induce apoptosis of A549 cells; however, inhibition of Nrf2 resulted in obvious apoptotic death of NOX4-overexpressed A549 cells, accompanied by a significant increase in H{sub 2}O{sub 2} level and decrease in GSH content. Besides, inhibition of Nrf2 could suppress cell growth and efficiently reverse the enhancement effect of NOX4 on cell growth. The in vivo data confirmed that inhibition of Nrf2 could interfere apoptosis resistance in NOX4-overexpressed A549 tumors and led to cell growth inhibition. In conclusion, these results reveal that Nrf2 is critically involved in redox adaptation regulation in NOX4-overexpressed NSCLC cells. Therefore, NOX4 and Nrf2 may be promising combination targets against malignant progression of NSCLC. - Highlights: • NOX4-derived H{sub 2}O{sub 2} upregulates Nrf2 expression and activity in NSCLC. • Nrf2 confers apoptosis resistance in NOX4-overexpressed NSCLC cells. • Inhibition of Nrf2 reverses the enhancement effect of NOX4 on cell growth.

  15. Ultrasound-guided biopsy of greater omentum: An effective method to trace the origin of unclear ascites

    Energy Technology Data Exchange (ETDEWEB)

    Que Yanhong [Department of Ultrasound, First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001 (China)], E-mail: quebaobao@yahoo.com.cn; Wang Xuemei [Department of Ultrasound, First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001 (China)], E-mail: wxmlmt@yahoo.com.cn; Liu Yanjun [Department of Ultrasound, First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001 (China)], E-mail: lyj7512@sina.com; Li Ping [Department of Ultrasound, First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001 (China)], E-mail: liping7213@sina.com; Ou Guocheng [Department of Ultrasound, First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001 (China)], E-mail: yang9951@126.com; Zhao Wenjing [Department of Ultrasound, First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001 (China)], E-mail: awk999@163.com

    2009-05-15

    Objectives: Thickened greater omentum is encountered with high frequency in patients with ascites. The purpose of our study was to assess the utility of greater omentum biopsy under the guidance of ultrasound (US) in tracing the origin of unclear ascites and differentiating benign and malignant ascites. Materials and methods: We retrospectively reviewed our institutional database for all records of greater omentum biopsy cases. One hundred and ninety-four patients with unclear ascites and thickened greater omentum were included in the study. The sonograms of greater omentum were evaluated before undergoing the ultrasound-guided biopsy and a biopsy was considered successful if a specific benign or malignant diagnosis was rendered by the pathologist. Results: Successful biopsy was rendered for 182 biopsy procedures (93.8%, 182/194) including tuberculosis (n = 114), chronic inflammation (n = 3), metastases (n = 58), malignant mesothelioma (n = 6) and pseudomyxoma peritonei (n = 1). Twelve biopsies were non-diagnostic. According to the results of biopsy and follow-up, the sensitivity and specificity of biopsy in distinguishing malignant ascites from benign ascities were respectively 95.6% (65/68) and 92.9% (117/126). The greater omentum of 84 cases of tuberculous peritonitis showed 'cerebral fissure' sign and was well seen as an omental cake infiltrated with irregular nodules when involved by carcinomatosis. No 'cerebral fissure' sign was observed in peritoneal carcinomatosis. The sensitivity and specificity of this sign in indicating the existence of tuberculous peritonitis were 73.5% (89/121) and 100% (73/73). Moreover, if the specific 'cerebral fissure' sign was combined with the biopsy results, the specificity of biopsy in distinguishing malignant ascites from benign ascits increased to 96.8% (122/126). Conclusion: Ultrasound-guided biopsy of greater omentum is an important and effective method to diagnose the unclear ascites for

  16. Development and aging of a brain neural stem cell niche.

    Science.gov (United States)

    Conover, Joanne C; Todd, Krysti L

    2017-08-01

    In the anterior forebrain, along the lateral wall of the lateral ventricles, a neurogenic stem cell niche is found in a region referred to as the ventricular-subventricular zone (V-SVZ). In rodents, robust V-SVZ neurogenesis provides new neurons to the olfactory bulb throughout adulthood; however, with increasing age stem cell numbers are reduced and neurogenic capacity is significantly diminished, but new olfactory bulb neurons continue to be produced even in old age. Humans, in contrast, show little to no new neurogenesis after two years of age and whether V-SVZ neural stem cells persist in the adult human brain remains unclear. Here, we review functional and organizational differences in the V-SVZ stem cell niche of mice and humans, and examine how aging affects the V-SVZ niche and its associated functions. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Clinical Implications of Intestinal Stem Cell Markers in Colorectal Cancer

    DEFF Research Database (Denmark)

    Espersen, Maiken Lise Marcker; Olsen, Jesper; Linnemann, Dorte

    2015-01-01

    Colorectal cancer (CRC) still has one of the highest incidence and mortality rate among cancers. Therefore, improved differential diagnostics and personalized treatment are still needed. Several intestinal stem cell markers have been found to be associated with CRC and might have a prognostic...... and predictive significance in CRC patients. This review provides an overview of the intestinal stem cell markers leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), B cell–specific Moloney murine leukemia virus insertion site 1 (BMI1), Musashi1 (MSI1), and sex-determining region y-box 9 (SOX9......) and their implications in human CRC. The exact roles of the intestinal stem cell markers in CRC development and progression remain unclear; however, high expression of these stem cell markers have a potential prognostic significance and might be implicated in chemotherapy resistance...

  18. MRP proteins as potential mediators of heavy metal resistance in zebrafish cells.

    Science.gov (United States)

    Long, Yong; Li, Qing; Wang, Youhui; Cui, Zongbin

    2011-04-01

    Acquired resistance of mammalian cells to heavy metals is closely relevant to enhanced expression of several multidrug resistance-associated proteins (MRP), but it remains unclear whether MRP proteins confer resistance to heavy metals in zebrafish. In this study, we obtained zebrafish (Danio rerio) fibroblast-like ZF4 cells with resistance to toxic heavy metals after chronic cadmium exposure and selection for 6months. These cadmium-resistant cells (ZF4-Cd) were maintained in 5μM cadmium and displayed cross-resistance to cadmium, mercury, arsenite and arsenate. ZF4-Cd cells remained the resistance to heavy metals after protracted culture in cadmium-free medium. In comparison with ZF4-WT cells, ZF4-Cd cells exhibited accelerated rate of cadmium excretion, enhanced activity of MRP-like transport, elevated expression of abcc2, abcc4 and mt2 genes, and increased content of cellular GSH. Inhibition of MRP-like transport activity, GSH biosynthesis and GST activity significantly attenuated the resistance of ZF4-Cd cells to heavy metals. The results indicate that some of MRP transporters are involved in the efflux of heavy metals conjugated with cellular GSH and thus play crucial roles in heavy metal detoxification of zebrafish cells. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. Circumvention of multi-drug resistance of cancer cells by Chinese herbal medicines.

    Science.gov (United States)

    Chai, Stella; To, Kenneth Kw; Lin, Ge

    2010-07-25

    Multi-drug resistance (MDR) of cancer cells severely limits therapeutic outcomes. A proposed mechanism for MDR involves the efflux of anti-cancer drugs from cancer cells, primarily mediated by ATP-binding cassette (ABC) membrane transporters including P-glycoprotein. This article reviews the recent progress of using active ingredients, extracts and formulae from Chinese medicine (CM) in circumventing ABC transporters-mediated MDR. Among the ABC transporters, Pgp is the most extensively studied for its role in MDR reversal effects. While other MDR reversal mechanisms remain unclear, Pgp inhibition is a criterion for further mechanistic study. More mechanistic studies are needed to fully establish the pharmacological effects of potential MDR reversing agents.

  20. Systematization of the Mechanism by Which Plasma Irradiation Causes Cell Growth and Tumor Cell Death

    Science.gov (United States)

    Shimizu, Nobuyuki

    2015-09-01

    New methods and technologies have improved minimally invasive surgical treatment and saved numerous patients. Recently, plasma irradiation has been demonstrated that might be useful in medical field and the plasma irradiation device is expected to become practically applicable. Mild plasma coagulator showed some advantages such as hemostasis and adhesion reduction in experimental animal model, but the mechanism of plasma irradiation remains unclear. Our study group aim to clarify the mechanism of plasma irradiation effects, mainly focusing on oxidative stress using cultured cell lines and small animal model. First, a study using cultured cell lines showed that the culture medium that was activated by plasma irradiation (we called this kind of medium as ``PAM'' -plasma activated medium-) induced tumor cell death. Although this effect was mainly found to be due to hydrogen peroxide, the remaining portion was considered as the specific effect of the plasma irradiation and we are now studying focusing on this effect. Second, we established a mouse intra-peritoneal adhesion model and checked biological reaction that occurred in the adhesion part. Histopathological study showed inflammatory cells infiltration into adhesion part and the expression of PTX3 that might involve tissue repair around adhesion part. We also confirmed that cytokines IL-6 and IL-10 might be useful as a marker of adhesion formation in this model. Applying ``PAM'' or mild plasma irradiation in this model, we examine the effects of plasma on inflamed cells. The samples in these experiments would be applied to targeted proteomics analysis, and we aim to demonstrate the systematization of the cell's reaction by plasma irradiation.

  1. Therapeutic impact of [18F]fluoride positron-emission tomography/computed tomography on patients with unclear foot pain

    International Nuclear Information System (INIS)

    Fischer, Dorothee Rita; Hesselmann, Rolf; Johayem, Anass; Hany, Thomas F.; Schulthess, Gustav K. von; Strobel, Klaus; Maquieira, Gerardo J.; Espinosa, Norman; Zanetti, Marco

    2010-01-01

    To evaluate the therapeutic impact of [ 18 F]fluoride positron-emission tomography/computed tomography ([ 18 F]fluoride PET/CT) imaging on patients with unclear foot pain. Twenty-eight patients were prospectively included in this study. Therapeutic management was defined by two experienced dedicated foot surgeons before and after [ 18 F]fluoride PET/CT imaging. Twenty-six patients underwent cross-sectional imaging [CT, magnetic resonance (MR)] prior to PET/CT. A retrospective analysis of the magnetic resonance imaging (MRI) diagnoses was performed when a therapy change occurred after PET/CT imaging. In 13/28 (46%) patients therapeutic management was changed due to PET/CT results. Management changes occurred in patients with the following diagnoses: os trigonum syndrome; sinus tarsi syndrome; os tibiale externum syndrome; osteoarthritis of several joints; non-consolidated fragments; calcaneo-navicular coalition; plantar fasciitis; insertional tendinopathy; suggestion of periostitis; neoarticulations between metatarsal bones. Os trigonum, os tibiale externum, subtalar osteoarthritis and plantar fasciitis were only seen to be active on PET/CT images but not on MR images. [ 18 F]fluoride PET/CT has a substantial therapeutic impact on management in patients with unclear foot pain. (orig.)

  2. Intervertebral Disc Degeneration : The Role of the Mitochondrial Pathway in Annulus Fibrosus Cell Apoptosis Induced by Overload

    OpenAIRE

    Rannou, François; Lee, Tzong-Shyuan; Zhou, Rui-Hai; Chin, Jennie; Lotz, Jeffrey C.; Mayoux-Benhamou, Marie-Anne; Barbet, Jacques Patrick; Chevrot, Alain; Shyy, John Y.-J.

    2004-01-01

    Degeneration of the intervertebral disk (IVD) is a major pathological process implicated in low back pain and is a prerequisite to disk herniation. Although mechanical stress is an important modulator of the degeneration, the underlying molecular mechanism remains unclear. The association of human IVD degeneration, assessed by magnetic resonance imaging, with annulus fibrosus cell apoptosis and anti-cytochrome c staining revealed that the activation of the mitochondria-dependent apoptosome wa...

  3. Cell-to-cell communication and cellular environment alter the somatostatin status of delta cells

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Catriona, E-mail: catriona.kelly@qub.ac.uk [SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine (United Kingdom); Flatt, Peter R.; McClenaghan, Neville H. [SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine (United Kingdom)

    2010-08-20

    Research highlights: {yields} TGP52 cells display enhanced functionality in pseudoislet form. {yields} Somatostatin content was reduced, but secretion increased in high glucose conditions. {yields} Cellular interactions and environment alter the somatostatin status of TGP52 cells. -- Abstract: Introduction: Somatostatin, released from pancreatic delta cells, is a potent paracrine inhibitor of insulin and glucagon secretion. Islet cellular interactions and glucose homeostasis are essential to maintain normal patterns of insulin secretion. However, the importance of cell-to-cell communication and cellular environment in the regulation of somatostatin release remains unclear. Methods: This study employed the somatostatin-secreting TGP52 cell line maintained in DMEM:F12 (17.5 mM glucose) or DMEM (25 mM glucose) culture media. The effect of pseudoislet formation and culture medium on somatostatin content and release in response to a variety of stimuli was measured by somatostatin EIA. In addition, the effect of pseudoislet formation on cellular viability (MTT and LDH assays) and proliferation (BrdU ELISA) was determined. Results: TGP52 cells readily formed pseudoislets and showed enhanced functionality in three-dimensional form with increased E-cadherin expression irrespective of the culture environment used. However, culture in DMEM decreased cellular somatostatin content (P < 0.01) and increased somatostatin secretion in response to a variety of stimuli including arginine, calcium and PMA (P < 0.001) when compared with cells grown in DMEM:F12. Configuration of TGP52 cells as pseudoislets reduced the proliferative rate and increased cellular cytotoxicity irrespective of culture medium used. Conclusions: Somatostatin secretion is greatly facilitated by cell-to-cell interactions and E-cadherin expression. Cellular environment and extracellular glucose also significantly influence the function of delta cells.

  4. Cell-to-cell communication and cellular environment alter the somatostatin status of delta cells

    International Nuclear Information System (INIS)

    Kelly, Catriona; Flatt, Peter R.; McClenaghan, Neville H.

    2010-01-01

    Research highlights: → TGP52 cells display enhanced functionality in pseudoislet form. → Somatostatin content was reduced, but secretion increased in high glucose conditions. → Cellular interactions and environment alter the somatostatin status of TGP52 cells. -- Abstract: Introduction: Somatostatin, released from pancreatic delta cells, is a potent paracrine inhibitor of insulin and glucagon secretion. Islet cellular interactions and glucose homeostasis are essential to maintain normal patterns of insulin secretion. However, the importance of cell-to-cell communication and cellular environment in the regulation of somatostatin release remains unclear. Methods: This study employed the somatostatin-secreting TGP52 cell line maintained in DMEM:F12 (17.5 mM glucose) or DMEM (25 mM glucose) culture media. The effect of pseudoislet formation and culture medium on somatostatin content and release in response to a variety of stimuli was measured by somatostatin EIA. In addition, the effect of pseudoislet formation on cellular viability (MTT and LDH assays) and proliferation (BrdU ELISA) was determined. Results: TGP52 cells readily formed pseudoislets and showed enhanced functionality in three-dimensional form with increased E-cadherin expression irrespective of the culture environment used. However, culture in DMEM decreased cellular somatostatin content (P < 0.01) and increased somatostatin secretion in response to a variety of stimuli including arginine, calcium and PMA (P < 0.001) when compared with cells grown in DMEM:F12. Configuration of TGP52 cells as pseudoislets reduced the proliferative rate and increased cellular cytotoxicity irrespective of culture medium used. Conclusions: Somatostatin secretion is greatly facilitated by cell-to-cell interactions and E-cadherin expression. Cellular environment and extracellular glucose also significantly influence the function of delta cells.

  5. Total glucosides of paeony inhibits Th1/Th17 cells via decreasing dendritic cells activation in rheumatoid arthritis.

    Science.gov (United States)

    Lin, Jinpiao; Xiao, Lianbo; Ouyang, Guilin; Shen, Yu; Huo, Rongfen; Zhou, Zhou; Sun, Yue; Zhu, Xianjin; Zhang, Jie; Shen, Baihua; Li, Ningli

    2012-12-01

    Total glucoside of paeony (TGP), an active compound extracted from paeony root, has been used in therapy for rheumatoid arthritis (RA). Th1 and Th17 cells are now believed to play crucial roles in the lesions of RA. However, the molecular mechanism of TGP in inhibition of Th1 and Th17 cells remains unclear. In this study, we found that TGP treatment significantly decreased percentage and number of Th1 and Th17 cells in collagen induced arthritis (CIA) mice. Consistently, treatment with TGP decreased expression of T-bet and RORγt as well as phosphorylation of STAT1 and STAT3. In particular, TGP treatment inhibited dendritic cells (DCs) maturation and reduced production of IL-12 and IL-6. Moreover, TGP-treatment RA patients showed shank population of matured DCs and IFN-γ-, IL-17-producing cells. Taken together, our results demonstrated that TGP inhibited maturation and activation of DCs, which led to impaired Th1 and Th17 differentiation in vivo. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Autoreactive T Cells and Chronic Fungal Infection Drive Esophageal Carcinogenesis

    Science.gov (United States)

    Zhu, Feng; Willette-Brown, Jami; Song, Na-Young; Lomada, Dakshayani; Song, Yongmei; Xue, Liyan; Gray, Zane; Zhao, Zitong; Davis, Sean R.; Sun, Zhonghe; Zhang, Peilin; Wu, Xiaolin; Zhan, Qimin; Richie, Ellen R.; Hu, Yinling

    2018-01-01

    SUMMARY Humans with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), a T cell–driven autoimmune disease caused by impaired central tolerance, are susceptible to developing chronic fungal infection and esophageal squamous cell carcinoma (ESCC). However, the relationship between autoreactive T cells and chronic fungal infection in ESCC development remains unclear. We find that kinase-dead Ikkα knockin mice develop phenotypes reminiscent of APECED, including impaired central tolerance, autoreactive T cells, chronic fungal infection, and ESCCs expressing specific human ESCC markers. Using this model, we investigated the potential link between ESCC and fungal infection. Autoreactive CD4 T cells permit fungal infection and incite tissue injury and inflammation. Antifungal treatment or depletion of autoreactive CD4 T cells rescues, whereas oral fungal administration promotes, ESCC development. Inhibition of inflammation or EGFR activity decreases fungal burden. Importantly, fungal infection is highly associated with ESCCs in non-autoimmune human patients. Therefore, autoreactive T cells and chronic fungal infection, fostered by inflammation and epithelial injury, promote ESCC development. PMID:28407484

  7. Activation of natural killer T Cells promotes M2 macrophage polarization in adipose tissue and improves systemic glucose tolerance via interleukin-4 (IL-4)/STAT6 protein signalling axis in obesity

    NARCIS (Netherlands)

    Ji, Y.; Sun, S.; Xu, Aimin; Bhargava, P.; Yang, Liu; Lam, K.S.L.; Gao, Bin; Lee, Chih-Hao; Kersten, A.H.; Qi, L.

    2012-01-01

    Natural killer T (NKT) cells are important therapeutic targets in various disease models and are under clinical trials for cancer patients. However, their function in obesity and type 2 diabetes remains unclear. Our data show that adipose tissues of both mice and humans contain a population of type

  8. Viral RNA-Unprimed Rig-I Restrains Stat3 Activation in the Modulation of Regulatory T Cell/Th17 Cell Balance.

    Science.gov (United States)

    Yang, Hui; Guo, He-Zhou; Li, Xian-Yang; Lin, Jian; Zhang, Wu; Zhao, Jun-Mei; Zhang, Hong-Xin; Chen, Sai-Juan; Chen, Zhu; Zhu, Jiang

    2017-07-01

    Innate immunity activation by viral RNA-primed retinoid acid inducible gene-I (Rig-I) in CD4 + T cells antagonizes TGFβ signaling to suppress the differentiation of regulatory T cells (Tregs). However, how viral RNA-unliganded Rig-I (apo-Rig-I) modulates Treg generation remains unclear. In this article, we show that, in the absence of viral infection, Treg differentiation of Rig-I -/- CD4 + T cells was compromised, in the presence of increased generation of Th17 cells and overactivation of Stat3, a critical regulator tilting the Treg/Th17 cell balance. Mechanistically, apo-Rig-I physically associates with Stat3, thereby inhibiting Jak1's association with Stat3 while facilitating Shp2's association to inhibit p-Stat3 levels. Interestingly, inhibition of Stat3 ameliorates the Treg/Th17 imbalance and the colitis observed in Rig-I -/- mice. Collectively, these results uncover an independent functional contribution of the apo-Rig-I/Stat3 interaction in the maintenance of Treg/Th17 cell balance. Copyright © 2017 by The American Association of Immunologists, Inc.

  9. Extreme Beta-Cell Deficiency in Pancreata of Dogs with Canine Diabetes.

    Directory of Open Access Journals (Sweden)

    Emily J Shields

    Full Text Available The pathophysiology of canine diabetes remains poorly understood, in part due to enigmatic clinical features and the lack of detailed histopathology studies. Canine diabetes, similar to human type 1 diabetes, is frequently associated with diabetic ketoacidosis at onset or after insulin omission. However, notable differences exist. Whereas human type 1 diabetes often occurs in children, canine diabetes is typically described in middle age to elderly dogs. Many competing theories have been proposed regarding the underlying cause of canine diabetes, from pancreatic atrophy to chronic pancreatitis to autoimmune mediated β-cell destruction. It remains unclear to what extent β-cell loss contributes to canine diabetes, as precise quantifications of islet morphometry have not been performed. We used high-throughput microscopy and automated image processing to characterize islet histology in a large collection of pancreata of diabetic dogs. Diabetic pancreata displayed a profound reduction in β-cells and islet endocrine cells. Unlike humans, canine non-diabetic islets are largely comprised of β-cells. Very few β-cells remained in islets of diabetic dogs, even in pancreata from new onset cases. Similarly, total islet endocrine cell number was sharply reduced in diabetic dogs. No compensatory proliferation or lymphocyte infiltration was detected. The majority of pancreata had no evidence of pancreatitis. Thus, canine diabetes is associated with extreme β-cell deficiency in both new and longstanding disease. The β-cell predominant composition of canine islets and the near-total absence of β-cells in new onset elderly diabetic dogs strongly implies that similar to human type 1 diabetes, β-cell loss underlies the pathophysiology of canine diabetes.

  10. Ubiquitin Ligase Cbl-b Is Involved in Icotinib (BPI-2009H)-Induced Apoptosis and G1 Phase Arrest of EGFR Mutation-Positive Non-Small-Cell Lung Cancer

    OpenAIRE

    Mu, Xiaodong; Zhang, Ye; Qu, Xiujuan; Hou, Kezuo; Kang, Jian; Hu, Xuejun; Liu, Yunpeng

    2013-01-01

    Epidermal growth factor receptor (EGFR) is one of the most promising targets for non-small-cell lung cancer (NSCLC). Icotinib, a highly selective EGFR tyrosine kinase inhibitor (EGFR-TKI), has shown promising clinical efficacy and safety in patients with NSCLC. The exact molecular mechanism of icotinib remains unclear. In this study, we first investigated the antiproliferative effect of icotinib on NSCLC cells. Icotinib significantly inhibited proliferation of the EGFR-mutated lung cancer HCC...

  11. A-π-D-π-A Electron-Donating Small Molecules for Solution-Processed Organic Solar Cells: A Review.

    Science.gov (United States)

    Wang, Zhen; Zhu, Lingyun; Shuai, Zhigang; Wei, Zhixiang

    2017-11-01

    Organic solar cells based on semiconducting polymers and small molecules have attracted considerable attention in the last two decades. Moreover, the power conversion efficiencies for solution-processed solar cells containing A-π-D-π-A-type small molecules and fullerenes have reached 11%. However, the method for designing high-performance, photovoltaic small molecules still remains unclear. In this review, recent studies on A-π-D-π-A electron-donating small molecules for organic solar cells are introduced. Moreover, the relationships between molecular properties and device performances are summarized, from which inspiration for the future design of high performance organic solar cells may be obtained. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. CD49b-dependent establishment of T helper cell memory.

    Science.gov (United States)

    Hanazawa, Asami; Hayashizaki, Koji; Shinoda, Kenta; Yagita, Hideo; Okumura, Ko; Löhning, Max; Hara, Takahiro; Tani-ichi, Shizue; Ikuta, Koichi; Eckes, Beate; Radbruch, Andreas; Tokoyoda, Koji; Nakayama, Toshinori

    2013-09-01

    CD4 T cells play a key role in immunological memory. We have demonstrated that professional memory CD4 T cells reside and rest in the bone marrow (BM). However, the molecular mechanisms of their establishment in the BM and their maintenance remain unclear. We here show that memory CD4 T cells express high levels of CD49b and that CD49b-deficient or -blocked memory CD4 T-cell precursors fail to migrate from blood into the marrow of the bone, and they especially fail to transmigrate through sinusoidal endothelial cells of the BM. In the marrow, memory CD4 T cells and the precursors contact stromal cells expressing collagen II that are specific ligands for CD49b. Interestingly, memory CD4 T cells on day 117 of an immune response also dock on IL-7(+)/collagen XI(+) stromal cells, whereas memory precursors on day 12 do not. These results indicate that the collagen receptor CD49b is required for the migration of memory CD4 T-cell precursors into their survival niches of the bone marrow.

  13. Natriuretic peptide receptor A inhibition suppresses gastric cancer development through reactive oxygen species-mediated G2/M cell cycle arrest and cell death.

    Science.gov (United States)

    Li, Zheng; Wang, Ji-Wei; Wang, Wei-Zhi; Zhi, Xiao-Fei; Zhang, Qun; Li, Bo-Wen; Wang, Lin-Jun; Xie, Kun-Ling; Tao, Jin-Qiu; Tang, Jie; Wei, Song; Zhu, Yi; Xu, Hao; Zhang, Dian-Cai; Yang, Li; Xu, Ze-Kuan

    2016-10-01

    Natriuretic peptide receptor A (NPRA), the major receptor for atrial natriuretic peptide (ANP), has been implicated in tumorigenesis; however, the role of ANP-NPRA signaling in the development of gastric cancer remains unclear. Immunohistochemical analyses indicated that NPRA expression was positively associated with gastric tumor size and cancer stage. NPRA inhibition by shRNA induced G2/M cell cycle arrest, cell death, and autophagy in gastric cancer cells, due to accumulation of reactive oxygen species (ROS). Either genetic or pharmacologic inhibition of autophagy led to caspase-dependent cell death. Therefore, autophagy induced by NPRA silencing may represent a cytoprotective mechanism. ROS accumulation activated c-Jun N-terminal kinase (JNK) and AMP-activated protein kinase (AMPK). ROS-mediated activation of JNK inhibited cell proliferation by disturbing cell cycle and decreased cell viability. In addition, AMPK activation promoted autophagy in NPRA-downregulated cancer cells. Overall, our results indicate that the inhibition of NPRA suppresses gastric cancer development and targeting NPRA may represent a promising strategy for the treatment of gastric cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Transport across the cell-membrane dictates nanoparticle fate and toxicity: a new paradigm in nanotoxicology

    Science.gov (United States)

    Guarnieri, Daniela; Sabella, Stefania; Muscetti, Ornella; Belli, Valentina; Malvindi, Maria Ada; Fusco, Sabato; de Luca, Elisa; Pompa, Pier Paolo; Netti, Paolo A.

    2014-08-01

    The toxicity of metallic nanoparticles (MNPs) has been fully ascertained, but the mechanisms underlying their cytotoxicity remain still largely unclear. Here we demonstrate that the cytotoxicity of MNPs is strictly reliant on the pathway of cellular internalization. In particular, if otherwise toxic gold, silver, and iron oxide NPs are forced through the cell membrane bypassing any form of active mechanism (e.g., endocytosis), no significant cytotoxic effect is registered. Pneumatically driven NPs across the cell membrane show a different distribution within the cytosol compared to NPs entering the cell by active endocytosis. Specifically, they exhibit free random Brownian motions within the cytosol and do not accumulate in lysosomes. Results suggest that intracellular accumulation of metallic nanoparticles into endo-lysosomal compartments is the leading cause of nanotoxicity, due to consequent nanoparticle degradation and in situ release of metal ions.The toxicity of metallic nanoparticles (MNPs) has been fully ascertained, but the mechanisms underlying their cytotoxicity remain still largely unclear. Here we demonstrate that the cytotoxicity of MNPs is strictly reliant on the pathway of cellular internalization. In particular, if otherwise toxic gold, silver, and iron oxide NPs are forced through the cell membrane bypassing any form of active mechanism (e.g., endocytosis), no significant cytotoxic effect is registered. Pneumatically driven NPs across the cell membrane show a different distribution within the cytosol compared to NPs entering the cell by active endocytosis. Specifically, they exhibit free random Brownian motions within the cytosol and do not accumulate in lysosomes. Results suggest that intracellular accumulation of metallic nanoparticles into endo-lysosomal compartments is the leading cause of nanotoxicity, due to consequent nanoparticle degradation and in situ release of metal ions. Electronic supplementary information (ESI) available. See DOI

  15. E-Cigarette Aerosol Exposure Induces Reactive Oxygen Species, DNA Damage, and Cell Death in Vascular Endothelial Cells.

    Science.gov (United States)

    Anderson, Chastain; Majeste, Andrew; Hanus, Jakub; Wang, Shusheng

    2016-12-01

    Cigarette smoking remains one of the leading causes of preventable death worldwide. Vascular cell death and dysfunction is a central or exacerbating component in the majority of cigarette smoking related pathologies. The recent development of the electronic nicotine delivery systems known as e-cigarettes provides an alternative to conventional cigarette smoking; however, the potential vascular health risks of e-cigarette use remain unclear. This study evaluates the effects of e-cigarette aerosol extract (EAE) and conventional cigarette smoke extract (CSE) on human umbilical vein endothelial cells (HUVECs). A laboratory apparatus was designed to produce extracts from e-cigarettes and conventional cigarettes according to established protocols for cigarette smoking. EAE or conventional CSE was applied to human vascular endothelial cells for 4-72 h, dependent on the assay. Treated cells were assayed for reactive oxygen species, DNA damage, cell viability, and markers of programmed cell death pathways. Additionally, the anti-oxidants α-tocopherol and n-acetyl-l-cysteine were used to attempt to rescue e-cigarette induced cell death. Our results indicate that e-cigarette aerosol is capable of inducing reactive oxygen species, causing DNA damage, and significantly reducing cell viability in a concentration dependent fashion. Immunofluorescent and flow cytometry analysis indicate that both the apoptosis and programmed necrosis pathways are triggered by e-cigarette aerosol treatment. Additionally, anti-oxidant treatment provides a partial rescue of the induced cell death, indicating that reactive oxygen species play a causal role in e-cigarette induced cytotoxicity. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  16. Governing Unclear Lines

    NARCIS (Netherlands)

    Justin, Peter Hakim; Vries, de Lotje

    2017-01-01

    South Sudan’s administrative boundaries stem from the colonial period. Since it gained independence in 2011, subsequent rounds of reshuffling of the political system, internal borders, and power relations have been a source of confusion, elite manipulation, and conflict throughout the country. This

  17. Role of fascin in the proliferation and invasiveness of esophageal carcinoma cells

    International Nuclear Information System (INIS)

    Xie, J.J.; Xu, L.Y.; Zhang, H.H.; Cai, W.J.; Mai, R.Q.; Xie, Y.M.; Yang, Z.M.; Niu, Y.D.; Shen, Z.Y.; Li, E.M.

    2005-01-01

    Fascin, an actin-bundling protein, induces membrane protrusions and increases cell motility in various transformed cells. The overexpression of fascin in esophageal squamous cell carcinoma (ESCC) has been described only recently, but the roles and mechanism still remained unclear. Here, by using RNA interference (RNAi), we have stably silenced the expression of the fascin in EC109 cells, an ESCC cell line. Down-regulation of fascin resulted in a suppression of cell proliferation and as well as a decrease in cell invasiveness. Furthermore, we revealed that fascin might have functions in regulating tumor growth in vivo. The effect of fascin on cell invasiveness correlated with the activation of matrix metalloproteases such as MMP-2 and MMP-9. We examined that fascin down-expression also led to a decrease of c-erbB-2 and β-catenin at the protein level. These results suggested that fascin might play crucial roles in regulating neoplasm progression of ESCC

  18. The interleukin-15 system suppresses T cell-mediated autoimmunity by regulating negative selection and nT(H)17 cell homeostasis in the thymus.

    Science.gov (United States)

    Hou, Mau-Sheng; Huang, Shih-Ting; Tsai, Ming-Han; Yen, Ching-Cheng; Lai, Yein-Gei; Liou, Yae-Huei; Lin, Chih-Kung; Liao, Nan-Shih

    2015-01-01

    The interleukin-15 (IL-15) system is important for regulating both innate and adaptive immune responses, however, its role in autoimmune disease remained unclear. Here we found that Il15(-/-) and Il15ra(-/-) mice spontaneously developed late-onset autoimmune phenotypes. CD4(+) T cells of the knockout mice showed elevated autoreactivity as demonstrated by the induction of lymphocyte infiltration in the lacrimal and salivary glands when transferred into nude mice. The antigen-presenting cells in the thymic medullary regions expressed IL-15 and IL-15Rα, whose deficiency resulted in insufficient negative selection and elevated number of natural IL-17A-producing CD4(+) thymocytes. These findings reveal previously unknown functions of the IL-15 system in thymocyte development, and thus a new layer of regulation in T cell-mediated autoimmunity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Acetyl CoA Carboxylase 2 Is Dispensable for CD8+ T Cell Responses.

    Directory of Open Access Journals (Sweden)

    Jang Eun Lee

    Full Text Available Differentiation of T cells is closely associated with dynamic changes in nutrient and energy metabolism. However, the extent to which specific metabolic pathways and molecular components are determinative of CD8+ T cell fate remains unclear. It has been previously established in various tissues that acetyl CoA carboxylase 2 (ACC2 regulates fatty acid oxidation (FAO by inhibiting carnitine palmitoyltransferase 1 (CPT1, a rate-limiting enzyme of FAO in mitochondria. Here, we explore the cell-intrinsic role of ACC2 in T cell immunity in response to infections. We report here that ACC2 deficiency results in a marginal increase of cellular FAO in CD8+ T cells, but does not appear to influence antigen-specific effector and memory CD8+ T cell responses during infection with listeria or lymphocytic choriomeningitis virus. These results suggest that ACC2 is dispensable for CD8+ T cell responses.

  20. Counterbalancing anti-adhesive effects of Tenascin-C through fibronectin expression in endothelial cells.

    Science.gov (United States)

    Radwanska, Agata; Grall, Dominique; Schaub, Sébastien; Divonne, Stéphanie Beghelli-de la Forest; Ciais, Delphine; Rekima, Samah; Rupp, Tristan; Sudaka, Anne; Orend, Gertraud; Van Obberghen-Schilling, Ellen

    2017-10-06

    Cellular fibronectin (FN) and tenascin-C (TNC) are prominent development- and disease-associated matrix components with pro- and anti-adhesive activity, respectively. Whereas both are present in the tumour vasculature, their functional interplay on vascular endothelial cells remains unclear. We have previously shown that basally-oriented deposition of a FN matrix restricts motility and promotes junctional stability in cultured endothelial cells and that this effect is tightly coupled to expression of FN. Here we report that TNC induces FN expression in endothelial cells. This effect counteracts the potent anti-adhesive activity of TNC and leads to the assembly of a dense highly-branched subendothelial matrix that enhances tubulogenic activity. These findings suggest that pro-angiogenic remodelling of the perivascular matrix may involve TNC-induced upregulation of FN in endothelial cells.

  1. Docosahexaenoic Acid Induces Cell Death in Human Non-Small Cell Lung Cancer Cells by Repressing mTOR via AMPK Activation and PI3K/Akt Inhibition

    Directory of Open Access Journals (Sweden)

    Nayeong Kim

    2015-01-01

    Full Text Available The anticancer properties and mechanism of action of omega-3 polyunsaturated fatty acids (ω3-PUFAs have been demonstrated in several cancers; however, the mechanism in lung cancer remains unclear. Here, we show that docosahexaenoic acid (DHA, a ω3-PUFA, induced apoptosis and autophagy in non-small cell lung cancer (NSCLC cells. DHA-induced cell death was accompanied by AMP-activated protein kinase (AMPK activation and inactivated phosphatidylinositol 3-kinase (PI3K/Akt/mammalian target of rapamycin (mTOR signaling. Knocking down AMPK and overexpressing Akt increased mTOR activity and attenuated DHA-induced cell death, suggesting that DHA induces cell death via AMPK- and Akt-regulated mTOR inactivation. This was confirmed in Fat-1 transgenic mice, which produce ω3-PUFAs. Lewis lung cancer (LLC tumor cells implanted into Fat-1 mice showed slower growth, lower phospho-Akt levels, and higher levels of apoptosis and autophagy than cells implanted into wild-type mice. Taken together, these data suggest that DHA-induced apoptosis and autophagy in NSCLC cells are associated with AMPK activation and PI3K/Akt inhibition, which in turn lead to suppression of mTOR; thus ω3-PUFAs may be utilized as potential therapeutic agents for NSCLC treatment.

  2. Programmed cell death in periodontitis: recent advances and future perspectives.

    Science.gov (United States)

    Song, B; Zhou, T; Yang, W L; Liu, J; Shao, L Q

    2017-07-01

    Periodontitis is a highly prevalent infectious disease, characterized by destruction of the periodontium, and is the main cause of tooth loss. Periodontitis is initiated by periodontal pathogens, while other risk factors including smoking, stress, and systemic diseases aggravate its progression. Periodontitis affects many people worldwide, but the molecular mechanisms by which pathogens and risk factors destroy the periodontium are unclear. Programmed cell death (PCD), different from necrosis, is an active cell death mediated by a cascade of gene expression events and can be mainly classified into apoptosis, autophagy, necroptosis, and pyroptosis. Although PCD is involved in many inflammatory diseases, its correlation with periodontitis is unclear. After reviewing the relevant published articles, we found that apoptosis has indeed been reported to play a role in periodontitis. However, the role of autophagy in periodontitis needs further verification. Additionally, implication of necroptosis or pyroptosis in periodontitis remains unknown. Therefore, we recommend future studies, which will unravel the pivotal role of PCD in periodontitis, allowing us to prevent, diagnose, and treat the disease, as well as predict its outcomes. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Medial Entorhinal Cortex Lesions Only Partially Disrupt Hippocampal Place Cells and Hippocampus-Dependent Place Memory

    Directory of Open Access Journals (Sweden)

    Jena B. Hales

    2014-11-01

    Full Text Available The entorhinal cortex provides the primary cortical projections to the hippocampus, a brain structure critical for memory. However, it remains unclear how the precise firing patterns of medial entorhinal cortex (MEC cells influence hippocampal physiology and hippocampus-dependent behavior. We found that complete bilateral lesions of the MEC resulted in a lower proportion of active hippocampal cells. The remaining active cells had place fields, but with decreased spatial precision and decreased long-term spatial stability. In addition, MEC rats were as impaired in the water maze as hippocampus rats, while rats with combined MEC and hippocampal lesions had an even greater deficit. However, MEC rats were not impaired on other hippocampus-dependent tasks, including those in which an object location or context was remembered. Thus, the MEC is not necessary for all types of spatial coding or for all types of hippocampus-dependent memory, but it is necessary for the normal acquisition of place memory.

  4. Developmental and Functional Control of Natural Killer Cells by Cytokines

    Directory of Open Access Journals (Sweden)

    Yang Wu

    2017-08-01

    Full Text Available Natural killer (NK cells are effective in combating infections and tumors and as such are tempting for adoptive transfer therapy. However, they are not homogeneous but can be divided into three main subsets, including cytotoxic, tolerant, and regulatory NK cells, with disparate phenotypes and functions in diverse tissues. The development and functions of such NK cells are controlled by various cytokines, such as fms-like tyrosine kinase 3 ligand (FL, kit ligand (KL, interleukin (IL-3, IL-10, IL-12, IL-18, transforming growth factor-β, and common-γ chain family cytokines, which operate at different stages by regulating distinct signaling pathways. Nevertheless, the specific roles of each cytokine that regulates NK cell development or that shapes different NK cell functions remain unclear. In this review, we attempt to describe the characteristics of each cytokine and the existing protocols to expand NK cells using different combinations of cytokines and feeder cells. A comprehensive understanding of the role of cytokines in NK cell development and function will aid the generation of better efficacy for adoptive NK cell treatment.

  5. Lipocalin 2 Enhances Migration and Resistance against Cisplatin in Endometrial Carcinoma Cells

    OpenAIRE

    Miyamoto, Tsutomu; Kashima, Hiroyasu; Yamada, Yasushi; Kobara, Hisanori; Asaka, Ryoichi; Ando, Hirofumi; Higuchi, Shotaro; Ida, Koichi; Mvunta, David Hamisi; Shiozawa, Tanri

    2016-01-01

    Purpose Lipocalin 2 (LCN2) is a secretory protein that is involved in various physiological processes including iron transport. We previously identified LCN2 as an up-regulated gene in endometrial carcinoma, and found that the overexpression of LCN2 and its receptor, SLC22A17, was associated with a poor prognosis. However, the functions and mechanism of action of LCN2 currently remain unclear. Methods The LCN2-overexpressing endometrial carcinoma cell lines, HHUA and RL95-2, and LCN2-low-expr...

  6. Non-apoptotic cell death associated with perturbations of macropinocytosis.

    Science.gov (United States)

    Maltese, William A; Overmeyer, Jean H

    2015-01-01

    Although macropinocytosis is widely recognized as a distinct form of fluid-phase endocytosis in antigen-presenting dendritic cells, it also occurs constitutively in many other normal and transformed cell types. Recent studies have established that various genetic or pharmacological manipulations can hyperstimulate macropinocytosis or disrupt normal macropinosome trafficking pathways, leading to accumulation of greatly enlarged cytoplasmic vacuoles. In some cases, this extreme vacuolization is associated with a unique form of non-apoptotic cell death termed "methuosis," from the Greek methuo (to drink to intoxication). It remains unclear whether cell death related to dysfunctional macropinocytosis occurs in normal physiological contexts. However, the finding that some types of cancer cells are particularly vulnerable to this unusual form of cell death has raised the possibility that small molecules capable of altering macropinosome trafficking or function might be useful as therapeutic agents against cancers that are resistant to drugs that work by inducing apoptosis. Herein we review examples of cell death associated with dysfunctional macropinocytosis and summarize what is known about the underlying mechanisms.

  7. Non-apoptotic cell death associated with perturbations of macropinocytosis

    Directory of Open Access Journals (Sweden)

    William A. Maltese

    2015-02-01

    Full Text Available Although macropinocytosis is widely recognized as a distinct form of fluid-phase endocytosis in antigen-presenting dendritic cells, it also occurs constitutively in many other normal and transformed cell types. Recent studies have established that various genetic or pharmacological manipulations can hyperstimulate macropinocytosis or disrupt normal macropinosome trafficking pathways, leading to accumulation of greatly enlarged cytoplasmic vacuoles. In some cases, this extreme vacuolization is associated with a unique form of non-apoptotic cell death termed ‘methuosis’, from the Greek methuo (to drink to intoxication. It remains unclear whether cell death related to dysfunctional macropinocytosis occurs in normal physiological contexts. However, the finding that some types of cancer cells are particularly vulnerable to this unusual form of cell death has raised the possibility that small molecules capable of altering macropinosome trafficking or function might be useful as therapeutic agents against cancers that are resistant to drugs that work by inducing apoptosis. Herein we review examples of cell death associated with dysfunctional macropinocytosis and summarize what is known about the underlying mechanisms.

  8. Airborne polycyclic aromatic hydrocarbons trigger human skin cells aging through aryl hydrocarbon receptor.

    Science.gov (United States)

    Qiao, Yuan; Li, Qiang; Du, Hong-Yang; Wang, Qiao-Wei; Huang, Ye; Liu, Wei

    2017-07-01

    Accumulating evidence suggests that polycyclic aromatic hydrocarbons (PAH) which adsorbed on the surface of ambient air particulate matters (PM), are the major toxic compound to cause cardiovascular and respiratory diseases, even cancer. However, its detrimental effects on human skin cell remain unclear. Here, we demonstrated that SRM1649b, a reference urban dust material of PAH, triggers human skin cells aging through cell cycle arrest, cell growth inhibition and apoptosis. Principally, SRM1649b facilitated Aryl hydrocarbon receptor (AhR) translocated into nucleus, subsequently activated ERK/MAPK signaling pathway, and upregulated aging-related genes expression. Most important, we found that AhR antagonist efficiently revert the aging of skin cells. Thus our novel findings firstly revealed the mechanism of skin aging under PAH contamination and provided potential strategy for clinical application. Copyright © 2017. Published by Elsevier Inc.

  9. Human neutrophils facilitate tumor cell transendothelial migration.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

  10. Interaction between adipose tissue-derived mesenchymal stem cells and regulatory T-cells

    NARCIS (Netherlands)

    A.U. Engela (Anja); C.C. Baan (Carla); A. Peeters (Anna); W. Weimar (Willem); M.J. Hoogduijn (Martin)

    2013-01-01

    textabstractMesenchymal stem cells (MSCs) exhibit immunosuppressive capabilities, which have evoked interest in their application as cell therapy in transplant patients. So far it has been unclear whether allogeneic MSCs and host regulatory T-cells (Tregs) functionally influence each other. We

  11. Hypothalamic stem cells control ageing speed partly through exosomal miRNAs.

    Science.gov (United States)

    Zhang, Yalin; Kim, Min Soo; Jia, Baosen; Yan, Jingqi; Zuniga-Hertz, Juan Pablo; Han, Cheng; Cai, Dongsheng

    2017-08-03

    It has been proposed that the hypothalamus helps to control ageing, but the mechanisms responsible remain unclear. Here we develop several mouse models in which hypothalamic stem/progenitor cells that co-express Sox2 and Bmi1 are ablated, as we observed that ageing in mice started with a substantial loss of these hypothalamic cells. Each mouse model consistently displayed acceleration of ageing-like physiological changes or a shortened lifespan. Conversely, ageing retardation and lifespan extension were achieved in mid-aged mice that were locally implanted with healthy hypothalamic stem/progenitor cells that had been genetically engineered to survive in the ageing-related hypothalamic inflammatory microenvironment. Mechanistically, hypothalamic stem/progenitor cells contributed greatly to exosomal microRNAs (miRNAs) in the cerebrospinal fluid, and these exosomal miRNAs declined during ageing, whereas central treatment with healthy hypothalamic stem/progenitor cell-secreted exosomes led to the slowing of ageing. In conclusion, ageing speed is substantially controlled by hypothalamic stem cells, partially through the release of exosomal miRNAs.

  12. Chronophin coordinates cell leading edge dynamics by controlling active cofilin levels

    Science.gov (United States)

    Delorme-Walker, Violaine; Seo, Ji-Yeon; Gohla, Antje; Fowler, Bruce; Bohl, Ben; DerMardirossian, Céline

    2015-01-01

    Cofilin, a critical player of actin dynamics, is spatially and temporally regulated to control the direction and force of membrane extension required for cell locomotion. In carcinoma cells, although the signaling pathways regulating cofilin activity to control cell direction have been established, the molecular machinery required to generate the force of the protrusion remains unclear. We show that the cofilin phosphatase chronophin (CIN) spatiotemporally regulates cofilin activity at the cell edge to generate persistent membrane extension. We show that CIN translocates to the leading edge in a PI3-kinase–, Rac1-, and cofilin-dependent manner after EGF stimulation to activate cofilin, promotes actin free barbed end formation, accelerates actin turnover, and enhances membrane protrusion. In addition, we establish that CIN is crucial for the balance of protrusion/retraction events during cell migration. Thus, CIN coordinates the leading edge dynamics by controlling active cofilin levels to promote MTLn3 cell protrusion. PMID:26324884

  13. Determinants of cell-to-cell variability in protein kinase signaling.

    Science.gov (United States)

    Jeschke, Matthias; Baumgärtner, Stephan; Legewie, Stefan

    2013-01-01

    Cells reliably sense environmental changes despite internal and external fluctuations, but the mechanisms underlying robustness remain unclear. We analyzed how fluctuations in signaling protein concentrations give rise to cell-to-cell variability in protein kinase signaling using analytical theory and numerical simulations. We characterized the dose-response behavior of signaling cascades by calculating the stimulus level at which a pathway responds ('pathway sensitivity') and the maximal activation level upon strong stimulation. Minimal kinase cascades with gradual dose-response behavior show strong variability, because the pathway sensitivity and the maximal activation level cannot be simultaneously invariant. Negative feedback regulation resolves this trade-off and coordinately reduces fluctuations in the pathway sensitivity and maximal activation. Feedbacks acting at different levels in the cascade control different aspects of the dose-response curve, thereby synergistically reducing the variability. We also investigated more complex, ultrasensitive signaling cascades capable of switch-like decision making, and found that these can be inherently robust to protein concentration fluctuations. We describe how the cell-to-cell variability of ultrasensitive signaling systems can be actively regulated, e.g., by altering the expression of phosphatase(s) or by feedback/feedforward loops. Our calculations reveal that slow transcriptional negative feedback loops allow for variability suppression while maintaining switch-like decision making. Taken together, we describe design principles of signaling cascades that promote robustness. Our results may explain why certain signaling cascades like the yeast pheromone pathway show switch-like decision making with little cell-to-cell variability.

  14. Wnt signaling maintains the notochord fate for progenitor cells and supports the posterior extension of the notochord

    OpenAIRE

    Ukita, Kanako; Hirahara, Shino; Oshima, Naoko; Imuta, Yu; Yoshimoto, Aki; Jang, Chuan-Wei; Oginuma, Masayuki; Saga, Yumiko; Behringer, Richard R.; Kondoh, Hisato; Sasaki, Hiroshi

    2009-01-01

    The notochord develops from notochord progenitor cells (NPCs) and functions as a major signaling center to regulate trunk and tail development. NPCs are initially specified in the node by Wnt and Nodal signals at the gastrula stage. However, the underlying mechanism that maintains the NPCs throughout embryogenesis to contribute to the posterior extension of the notochord remains unclear. Here, we demonstrate that Wnt signaling in the NPCs is essential for posterior extension of the notochord....

  15. Enrichment of human embryonic stem cell-derived NKX6.1-expressing pancreatic progenitor cells accelerates the maturation of insulin-secreting cells in vivo.

    Science.gov (United States)

    Rezania, Alireza; Bruin, Jennifer E; Xu, Jean; Narayan, Kavitha; Fox, Jessica K; O'Neil, John J; Kieffer, Timothy J

    2013-11-01

    Human embryonic stem cells (hESCs) are considered a potential alternative to cadaveric islets as a source of transplantable cells for treating patients with diabetes. We previously described a differentiation protocol to generate pancreatic progenitor cells from hESCs, composed of mainly pancreatic endoderm (PDX1/NKX6.1-positive), endocrine precursors (NKX2.2/synaptophysin-positive, hormone/NKX6.1-negative), and polyhormonal cells (insulin/glucagon-positive, NKX6.1-negative). However, the relative contributions of NKX6.1-negative versus NKX6.1-positive cell fractions to the maturation of functional β-cells remained unclear. To address this question, we generated two distinct pancreatic progenitor cell populations using modified differentiation protocols. Prior to transplant, both populations contained a high proportion of PDX1-expressing cells (~85%-90%) but were distinguished by their relatively high (~80%) or low (~25%) expression of NKX6.1. NKX6.1-high and NKX6.1-low progenitor populations were transplanted subcutaneously within macroencapsulation devices into diabetic mice. Mice transplanted with NKX6.1-low cells remained hyperglycemic throughout the 5-month post-transplant period whereas diabetes was reversed in NKX6.1-high recipients within 3 months. Fasting human C-peptide levels were similar between groups throughout the study, but only NKX6.1-high grafts displayed robust meal-, glucose- and arginine-responsive insulin secretion as early as 3 months post-transplant. NKX6.1-low recipients displayed elevated fasting glucagon levels. Theracyte devices from both groups contained almost exclusively pancreatic endocrine tissue, but NKX6.1-high grafts contained a greater proportion of insulin-positive and somatostatin-positive cells, whereas NKX6.1-low grafts contained mainly glucagon-expressing cells. Insulin-positive cells in NKX6.1-high, but not NKX6.1-low grafts expressed nuclear MAFA. Collectively, this study demonstrates that a pancreatic endoderm

  16. Multi-cellular natural killer (NK) cell clusters enhance NK cell activation through localizing IL-2 within the cluster

    Science.gov (United States)

    Kim, Miju; Kim, Tae-Jin; Kim, Hye Mi; Doh, Junsang; Lee, Kyung-Mi

    2017-01-01

    Multi-cellular cluster formation of natural killer (NK) cells occurs during in vivo priming and potentiates their activation to IL-2. However, the precise mechanism underlying this synergy within NK cell clusters remains unclear. We employed lymphocyte-laden microwell technologies to modulate contact-mediated multi-cellular interactions among activating NK cells and to quantitatively assess the molecular events occurring in multi-cellular clusters of NK cells. NK cells in social microwells, which allow cell-to-cell contact, exhibited significantly higher levels of IL-2 receptor (IL-2R) signaling compared with those in lonesome microwells, which prevent intercellular contact. Further, CD25, an IL-2R α chain, and lytic granules of NK cells in social microwells were polarized toward MTOC. Live cell imaging of lytic granules revealed their dynamic and prolonged polarization toward neighboring NK cells without degranulation. These results suggest that IL-2 bound on CD25 of one NK cells triggered IL-2 signaling of neighboring NK cells. These results were further corroborated by findings that CD25-KO NK cells exhibited lower proliferation than WT NK cells, and when mixed with WT NK cells, underwent significantly higher level of proliferation. These data highlights the existence of IL-2 trans-presentation between NK cells in the local microenvironment where the availability of IL-2 is limited.

  17. Circumvention of multi-drug resistance of cancer cells by Chinese herbal medicines

    Directory of Open Access Journals (Sweden)

    Lin Ge

    2010-07-01

    Full Text Available Abstract Multi-drug resistance (MDR of cancer cells severely limits therapeutic outcomes. A proposed mechanism for MDR involves the efflux of anti-cancer drugs from cancer cells, primarily mediated by ATP-binding cassette (ABC membrane transporters including P-glycoprotein. This article reviews the recent progress of using active ingredients, extracts and formulae from Chinese medicine (CM in circumventing ABC transporters-mediated MDR. Among the ABC transporters, Pgp is the most extensively studied for its role in MDR reversal effects. While other MDR reversal mechanisms remain unclear, Pgp inhibition is a criterion for further mechanistic study. More mechanistic studies are needed to fully establish the pharmacological effects of potential MDR reversing agents.

  18. Interaction of Defensins with Model Cell Membranes

    Science.gov (United States)

    Sanders, Lori K.; Schmidt, Nathan W.; Yang, Lihua; Mishra, Abhijit; Gordon, Vernita D.; Selsted, Michael E.; Wong, Gerard C. L.

    2009-03-01

    Antimicrobial peptides (AMPs) comprise a key component of innate immunity for a wide range of multicellular organisms. For many AMPs, activity comes from their ability to selectively disrupt and lyse bacterial cell membranes. There are a number of proposed models for this action, but the detailed molecular mechanism of selective membrane permeation remains unclear. Theta defensins are circularized peptides with a high degree of selectivity. We investigate the interaction of model bacterial and eukaryotic cell membranes with theta defensins RTD-1, BTD-7, and compare them to protegrin PG-1, a prototypical AMP, using synchrotron small angle x-ray scattering (SAXS). The relationship between membrane composition and peptide induced changes in membrane curvature and topology is examined. By comparing the membrane phase behavior induced by these different peptides we will discuss the importance of amino acid composition and placement on membrane rearrangement.

  19. Dnmt1 activity is dispensable in δ-cells but is essential for α-cell homeostasis.

    Science.gov (United States)

    Damond, Nicolas; Thorel, Fabrizio; Kim, Seung K; Herrera, Pedro L

    2017-07-01

    In addition to β-cells, pancreatic islets contain α- and δ-cells, which respectively produce glucagon and somatostatin. The reprogramming of these two endocrine cell types into insulin producers, as observed after a massive β-cell ablation in mice, may help restoring a functional β-cell mass in type 1 diabetes. Yet, the spontaneous α-to-β and δ-to-β conversion processes are relatively inefficient in adult animals and the underlying epigenetic mechanisms remain unclear. Several studies indicate that the conserved chromatin modifiers DNA methyltransferase 1 (Dnmt1) and Enhancer of zeste homolog 2 (Ezh2) are important for pancreas development and restrict islet cell plasticity. Here, to investigate the role of these two enzymes in α- and δ-cell development and fate maintenance, we genetically inactivated them in each of these two cell types. We found that loss of Dnmt1 does not enhance the conversion of α- or δ-cells toward a β-like fate. In addition, while Dnmt1 was dispensable for the development of these two cell types, we noticed a gradual loss of α-, but not δ-cells in adult mice. Finally, we found that Ezh2 inactivation does not enhance α-cell plasticity, and, contrary to what is observed in β-cells, does not impair α-cell proliferation. Our results indicate that both Dnmt1 and Ezh2 play distinct roles in the different islet cell types. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. A novel role for the cell cycle regulatory complex cyclin D1-CDK4 in gluconeogenesis

    OpenAIRE

    Hosooka, Tetsuya; Ogawa, Wataru

    2016-01-01

    Dysregulation of gluconeogenesis is a key pathological feature of type 2 diabetes. However, the molecular mechanisms underlying the regulation of gluconeogenesis remain unclear. Bhalla et?al. recently reported that cyclin D1 suppresses hepatic gluconeogenesis through CDK4?dependent phosphorylation of PGC1alpha and consequent inhibition of its activity. The cyclin D1?CDK4 might thus serve as an important link between the cell cycle and control of energy metabolism through modulation of PGC1alp...

  1. Constituents of Propolis: Chrysin, Caffeic Acid, p-Coumaric Acid, and Ferulic Acid Induce PRODH/POX-Dependent Apoptosis in Human Tongue Squamous Cell Carcinoma Cell (CAL-27).

    Science.gov (United States)

    Celińska-Janowicz, Katarzyna; Zaręba, Ilona; Lazarek, Urszula; Teul, Joanna; Tomczyk, Michał; Pałka, Jerzy; Miltyk, Wojciech

    2018-01-01

    Propolis evokes several therapeutic properties, including anticancer activity. These activities are attributed to the action of polyphenols. Previously it has been demonstrated, that one of the most abundant polyphenolic compounds in ethanolic extracts of propolis are chrysin, caffeic acid, p -coumaric acid, and ferulic acid. Although their pro-apoptotic activity on human tongue squamous cell carcinoma cells (CAL-27) was established previously, the detailed mechanism of this process remains unclear. Considering the crucial role of proline metabolism and proline dehydrogenase/proline oxidase (PRODH/POX) in the regulation of cancer cell survival/apoptosis, we studied these processes in polyphenol-treated CAL-27 cells. All studied polyphenols evoked anti-proliferative activity, accompanied by increased PRODH/POX, P53, active caspases-3 and -9 expressions and decreased collagen biosynthesis, prolidase activity and proline concentration in CAL-27 cells. These data suggest that polyphenols of propolis induce PRODH/POX-dependent apoptosis through up-regulation of mitochondrial proline degradation and down-regulation of proline utilization for collagen biosynthesis.

  2. B Cells Negatively Regulate the Establishment of CD49b(+)T-bet(+) Resting Memory T Helper Cells in the Bone Marrow.

    Science.gov (United States)

    Hojyo, Shintaro; Sarkander, Jana; Männe, Christian; Mursell, Mathias; Hanazawa, Asami; Zimmel, David; Zhu, Jinfang; Paul, William E; Fillatreau, Simon; Löhning, Max; Radbruch, Andreas; Tokoyoda, Koji

    2016-01-01

    During an immune reaction, some antigen-experienced CD4 T cells relocate from secondary lymphoid organs (SLOs) to the bone marrow (BM) in a CD49b-dependent manner and reside and rest there as professional memory CD4 T cells. However, it remains unclear how the precursors of BM memory CD4 T cells are generated in the SLOs. While several studies have so far shown that B cell depletion reduces the persistence of memory CD4 T cells in the spleen, we here show that B cell depletion enhances the establishment of memory CD4 T cells in the BM and that B cell transfer conversely suppresses it. Interestingly, the number of antigen-experienced CD4 T cells in the BM synchronizes the number of CD49b(+)T-bet(+) antigen-experienced CD4 T cells in the spleen. CD49b(+)T-bet(+) antigen-experienced CD4 T cells preferentially localize in the red pulp area of the spleen and the BM in a T-bet-independent manner. We suggest that B cells negatively control the generation of CD49b(+)T-bet(+) precursors of resting memory CD4 T cells in the spleen and may play a role in bifurcation of activated effector and resting memory CD4 T cell lineages.

  3. The site of primary T cell activation is a determinant of the balance between intrahepatic tolerance and immunity

    OpenAIRE

    Bowen, David G.; Zen, Monica; Holz, Lauren; Davis, Thomas; McCaughan, Geoffrey W.; Bertolino, Patrick

    2004-01-01

    Hepatic immunobiology is paradoxical: although the liver possesses unusual tolerogenic properties, it is also the site of effective immune responses against multiple pathogens and subject to immune-mediated pathology. The mechanisms underlying this dichotomy remain unclear. Following previous work demonstrating that the liver may act as a site of primary T cell activation, we demonstrate here that the balance between immunity and tolerance in this organ is established by competition for prima...

  4. Total glucosides of paeony induces regulatory CD4(+)CD25(+) T cells by increasing Foxp3 demethylation in lupus CD4(+) T cells.

    Science.gov (United States)

    Zhao, Ming; Liang, Gong-ping; Tang, Mei-ni; Luo, Shuang-yan; Zhang, Jing; Cheng, Wen-jing; Chan, Tak-mao; Lu, Qian-jin

    2012-05-01

    Total glucosides of paeony (TGP), an active compound extracted from Paeony root, has been used in therapy for autoimmune diseases. However the molecular mechanism of TGP in the prevention of autoimmune response remains unclear. In this study, we found that TGP treatment significantly increased the percentage and number of Treg cells in lupus CD4(+) T cells. Further investigation revealed that treatment with TGP increased the expression of Foxp3 in lupus CD4(+) T cells by down-regulating Foxp3 promoter methylation levels. However, we couldn't observe similar results in healthy control CD4(+) T cells treated by TGP. Moreover, our results also showed that IFN-γ and IL-2 expression was enhanced in TGP-treated lupus CD4(+) T cells. These findings indicate that TGP inhibits autoimmunity in SLE patients possibly by inducing Treg cell differentiation, which may in turn be due to its ability to regulate the methylation status of the Foxp3 promoter and activate IFN-γ and IL-2 signaling. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Aging and insulin signaling differentially control normal and tumorous germline stem cells.

    Science.gov (United States)

    Kao, Shih-Han; Tseng, Chen-Yuan; Wan, Chih-Ling; Su, Yu-Han; Hsieh, Chang-Che; Pi, Haiwei; Hsu, Hwei-Jan

    2015-02-01

    Aging influences stem cells, but the processes involved remain unclear. Insulin signaling, which controls cellular nutrient sensing and organismal aging, regulates the G2 phase of Drosophila female germ line stem cell (GSC) division cycle in response to diet; furthermore, this signaling pathway is attenuated with age. The role of insulin signaling in GSCs as organisms age, however, is also unclear. Here, we report that aging results in the accumulation of tumorous GSCs, accompanied by a decline in GSC number and proliferation rate. Intriguingly, GSC loss with age is hastened by either accelerating (through eliminating expression of Myt1, a cell cycle inhibitory regulator) or delaying (through mutation of insulin receptor (dinR) GSC division, implying that disrupted cell cycle progression and insulin signaling contribute to age-dependent GSC loss. As flies age, DNA damage accumulates in GSCs, and the S phase of the GSC cell cycle is prolonged. In addition, GSC tumors (which escape the normal stem cell regulatory microenvironment, known as the niche) still respond to aging in a similar manner to normal GSCs, suggesting that niche signals are not required for GSCs to sense or respond to aging. Finally, we show that GSCs from mated and unmated females behave similarly, indicating that female GSC-male communication does not affect GSCs with age. Our results indicate the differential effects of aging and diet mediated by insulin signaling on the stem cell division cycle, highlight the complexity of the regulation of stem cell aging, and describe a link between ovarian cancer and aging. © 2014 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  6. Th17 Cells and Activated Dendritic Cells Are Increased in Vitiligo Lesions

    Science.gov (United States)

    Fuentes-Duculan, Judilyn; Moussai, Dariush; Gulati, Nicholas; Sullivan-Whalen, Mary; Gilleaudeau, Patricia; Cohen, Jules A.; Krueger, James G.

    2011-01-01

    Background Vitiligo is a common skin disorder, characterized by progressive skin de-pigmentation due to the loss of cutaneous melanocytes. The exact cause of melanocyte loss remains unclear, but a large number of observations have pointed to the important role of cellular immunity in vitiligo pathogenesis. Methodology/Principal Findings In this study, we characterized T cell and inflammation-related dermal dendritic cell (DC) subsets in pigmented non-lesional, leading edge and depigmented lesional vitiligo skin. By immunohistochemistry staining, we observed enhanced populations of CD11c+ myeloid dermal DCs and CD207+ Langerhans cells in leading edge vitiligo biopsies. DC-LAMP+ and CD1c+ sub-populations of dermal DCs expanded significantly in leading edge and lesional vitiligo skin. We also detected elevated tissue mRNA levels of IL-17A in leading edge skin biopsies of vitiligo patients, as well as IL-17A positive T cells by immunohistochemistry and immunofluorescence. Langerhans cells with activated inflammasomes were also noted in lesional vitiligo skin, along with increased IL-1ß mRNA, which suggest the potential of Langerhans cells to drive Th17 activation in vitiligo. Conclusions/Significance These studies provided direct tissue evidence that implicates active Th17 cells in vitiligo skin lesions. We characterized new cellular immune elements, in the active margins of vitiligo lesions (e.g. populations of epidermal and dermal dendritic cells subsets), which could potentially drive the inflammatory responses. PMID:21541348

  7. Cellular Microenvironment Dictates Androgen Production by Murine Fetal Leydig Cells in Primary Culture1

    Science.gov (United States)

    Carney, Colleen M.; Muszynski, Jessica L.; Strotman, Lindsay N.; Lewis, Samantha R.; O'Connell, Rachel L.; Beebe, David J.; Theberge, Ashleigh B.; Jorgensen, Joan S.

    2014-01-01

    ABSTRACT Despite the fact that fetal Leydig cells are recognized as the primary source of androgens in male embryos, the mechanisms by which steroidogenesis occurs within the developing testis remain unclear. A genetic approach was used to visualize and isolate fetal Leydig cells from remaining cells within developing mouse testes. Cyp11a1-Cre mice were bred to mT/mG dual reporter mice to target membrane-tagged enhanced green fluorescent protein (GFP) within steroidogenic cells, whereas other cells expressed membrane-tagged tandem-dimer tomato red. Fetal Leydig cell identity was validated using double-labeled immunohistochemistry against GFP and the steroidogenic enzyme 3beta-HSD, and cells were successfully isolated as indicated by qPCR results from sorted cell populations. Because fetal Leydig cells must collaborate with neighboring cells to synthesize testosterone, we hypothesized that the fetal Leydig cell microenvironment defined their capacity for androgen production. Microfluidic culture devices were used to measure androstenedione and testosterone production of fetal Leydig cells that were cultured in cell-cell contact within a mixed population, were isolated but remained in medium contact via compartmentalized co-culture with other testicular cells, or were isolated and cultured alone. Results showed that fetal Leydig cells maintained their identity and steroidogenic activity for 3–5 days in primary culture. Microenvironment dictated proficiency of testosterone production. As expected, fetal Leydig cells produced androstenedione but not testosterone when cultured in isolation. More testosterone accumulated in medium from mixed cultures than from compartmentalized co-cultures initially; however, co-cultures maintained testosterone synthesis for a longer time. These data suggest that a combination of cell-cell contact and soluble factors constitute the ideal microenvironment for fetal Leydig cell activity in primary culture. PMID:25143354

  8. Cell Type-specific Intrinsic Perithreshold Oscillations in Hippocampal GABAergic Interneurons.

    Science.gov (United States)

    Kang, Young-Jin; Lewis, Hannah Elisabeth Smashey; Young, Mason William; Govindaiah, Gubbi; Greenfield, Lazar John; Garcia-Rill, Edgar; Lee, Sang-Hun

    2018-04-15

    The hippocampus plays a critical role in learning, memory, and spatial processing through coordinated network activity including theta and gamma oscillations. Recent evidence suggests that hippocampal subregions (e.g., CA1) can generate these oscillations at the network level, at least in part, through GABAergic interneurons. However, it is unclear whether specific GABAergic interneurons generate intrinsic theta and/or gamma oscillations at the single-cell level. Since major types of CA1 interneurons (i.e., parvalbumin-positive basket cells (PVBCs), cannabinoid type 1 receptor-positive basket cells (CB 1 BCs), Schaffer collateral-associated cells (SCAs), neurogliaform cells and ivy cells) are thought to play key roles in network theta and gamma oscillations in the hippocampus, we tested the hypothesis that these cells generate intrinsic perithreshold oscillations at the single-cell level. We performed whole-cell patch-clamp recordings from GABAergic interneurons in the CA1 region of the mouse hippocampus in the presence of synaptic blockers to identify intrinsic perithreshold membrane potential oscillations. The majority of PVBCs (83%), but not the other interneuron subtypes, produced intrinsic perithreshold gamma oscillations if the membrane potential remained above -45 mV. In contrast, CB 1 BCs, SCAs, neurogliaform cells, ivy cells, and the remaining PVBCs (17%) produced intrinsic theta, but not gamma, oscillations. These oscillations were prevented by blockers of persistent sodium current. These data demonstrate that the major types of hippocampal interneurons produce distinct frequency bands of intrinsic perithreshold membrane oscillations. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. T Cell Receptor Vβ Staining Identifies the Malignant Clone in Adult T cell Leukemia and Reveals Killing of Leukemia Cells by Autologous CD8+ T cells.

    Directory of Open Access Journals (Sweden)

    Aileen G Rowan

    2016-11-01

    Full Text Available There is growing evidence that CD8+ cytotoxic T lymphocyte (CTL responses can contribute to long-term remission of many malignancies. The etiological agent of adult T-cell leukemia/lymphoma (ATL, human T lymphotropic virus type-1 (HTLV-1, contains highly immunogenic CTL epitopes, but ATL patients typically have low frequencies of cytokine-producing HTLV-1-specific CD8+ cells in the circulation. It remains unclear whether patients with ATL possess CTLs that can kill the malignant HTLV-1 infected clone. Here we used flow cytometric staining of TCRVβ and cell adhesion molecule-1 (CADM1 to identify monoclonal populations of HTLV-1-infected T cells in the peripheral blood of patients with ATL. Thus, we quantified the rate of CD8+-mediated killing of the putative malignant clone in ex vivo blood samples. We observed that CD8+ cells from ATL patients were unable to lyse autologous ATL clones when tested directly ex vivo. However, short in vitro culture restored the ability of CD8+ cells to kill ex vivo ATL clones in some donors. The capacity of CD8+ cells to lyse HTLV-1 infected cells which expressed the viral sense strand gene products was significantly enhanced after in vitro culture, and donors with an ATL clone that expressed the HTLV-1 Tax gene were most likely to make a detectable lytic CD8+ response to the ATL cells. We conclude that some patients with ATL possess functional tumour-specific CTLs which could be exploited to contribute to control of the disease.

  10. HJURP regulates cellular senescence in human fibroblasts and endothelial cells via a p53-dependent pathway.

    Science.gov (United States)

    Heo, Jong-Ik; Cho, Jung Hee; Kim, Jae-Ryong

    2013-08-01

    Holliday junction recognition protein (HJURP), a centromere protein-A (CENP-A) histone chaperone, mediates centromere-specific assembly of CENP-A nucleosome, contributing to high-fidelity chromosome segregation during cell division. However, the role of HJURP in cellular senescence of human primary cells remains unclear. We found that the expression levels of HJURP decreased in human dermal fibroblasts and umbilical vein endothelial cells in replicative or premature senescence. Ectopic expression of HJURP in senescent cells partially overcame cell senescence. Conversely, downregulation of HJURP in young cells led to premature senescence. p53 knockdown, but not p16 knockdown, abolished senescence phenotypes caused by HJURP reduction. These data suggest that HJURP plays an important role in the regulation of cellular senescence through a p53-dependent pathway and might contribute to tissue or organismal aging and protection of cellular transformation.

  11. Stable SET knockdown in breast cell carcinoma inhibits cell migration and invasion

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jie [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Yang, Xi-fei [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Ren, Xiao-hu [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Meng, Xiao-jing [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China); Huang, Hai-yan [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Zhao, Qiong-hui [Shenzhen Entry-Exit Inspection and Quarantine Bureau, Shenzhen (China); Yuan, Jian-hui; Hong, Wen-xu; Xia, Bo; Huang, Xin-feng; Zhou, Li [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Liu, Jian-jun, E-mail: bio-research@hotmail.com [Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen (China); Zou, Fei, E-mail: zoufei616@163.com [Department of Occupational Health and Occupational Medicine, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou (China)

    2014-10-10

    Highlights: • We employed RNA interference to knockdown SET expression in breast cancer cells. • Knockdown of SET expression inhibits cell proliferation, migration and invasion. • Knockdown of SET expression increases the activity and expression of PP2A. • Knockdown of SET expression decreases the expression of MMP-9. - Abstract: Breast cancer is the most malignant tumor for women, however, the mechanisms underlying this devastating disease remain unclear. SET is an endogenous inhibitor of protein phosphatase 2A (PP2A) and involved in many physiological and pathological processes. SET could promote the occurrence of tumor through inhibiting PP2A. In this study, we explore the role of SET in the migration and invasion of breast cancer cells MDA-MB-231 and ZR-75-30. The stable suppression of SET expression through lentivirus-mediated RNA interference (RNAi) was shown to inhibit the growth, migration and invasion of breast cancer cells. Knockdown of SET increases the activity and expression of PP2Ac and decrease the expression of matrix metalloproteinase 9 (MMP-9). These data demonstrate that SET may be involved in the pathogenic processes of breast cancer, indicating that SET can serve as a potential therapeutic target for the treatment of breast cancer.

  12. Stable SET knockdown in breast cell carcinoma inhibits cell migration and invasion

    International Nuclear Information System (INIS)

    Li, Jie; Yang, Xi-fei; Ren, Xiao-hu; Meng, Xiao-jing; Huang, Hai-yan; Zhao, Qiong-hui; Yuan, Jian-hui; Hong, Wen-xu; Xia, Bo; Huang, Xin-feng; Zhou, Li; Liu, Jian-jun; Zou, Fei

    2014-01-01

    Highlights: • We employed RNA interference to knockdown SET expression in breast cancer cells. • Knockdown of SET expression inhibits cell proliferation, migration and invasion. • Knockdown of SET expression increases the activity and expression of PP2A. • Knockdown of SET expression decreases the expression of MMP-9. - Abstract: Breast cancer is the most malignant tumor for women, however, the mechanisms underlying this devastating disease remain unclear. SET is an endogenous inhibitor of protein phosphatase 2A (PP2A) and involved in many physiological and pathological processes. SET could promote the occurrence of tumor through inhibiting PP2A. In this study, we explore the role of SET in the migration and invasion of breast cancer cells MDA-MB-231 and ZR-75-30. The stable suppression of SET expression through lentivirus-mediated RNA interference (RNAi) was shown to inhibit the growth, migration and invasion of breast cancer cells. Knockdown of SET increases the activity and expression of PP2Ac and decrease the expression of matrix metalloproteinase 9 (MMP-9). These data demonstrate that SET may be involved in the pathogenic processes of breast cancer, indicating that SET can serve as a potential therapeutic target for the treatment of breast cancer

  13. Dissecting human cerebral organoids and fetal neocortex using single-cell RNAseq

    Science.gov (United States)

    Treutlein, Barbara

    Cerebral organoids - three-dimensional cultures of human cerebral tissue derived from pluripotent stem cells - have emerged as models of human cortical development. However, the extent to which in vitro organoid systems recapitulate neural progenitor cell proliferation and neuronal differentiation programs observed in vivo remains unclear. Here we use single-cell RNA sequencing (scRNA-seq) to dissect and compare cell composition and progenitor-to-neuron lineage relationships in human cerebral organoids and fetal neocortex. Covariation network analysis using the fetal neocortex data reveals known and novel interactions among genes central to neural progenitor proliferation and neuronal differentiation. In the organoid, we detect diverse progenitors and differentiated cell types of neuronal and mesenchymal lineages, and identify cells that derived from regions resembling the fetal neocortex. We find that these organoid cortical cells use gene expression programs remarkably similar to those of the fetal tissue in order to organize into cerebral cortex-like regions. Our comparison of in vivo and in vitro cortical single cell transcriptomes illuminates the genetic features underlying human cortical development that can be studied in organoid cultures.

  14. Autoimmune Th17 Cells Induced Synovial Stromal and Innate Lymphoid Cell Secretion of the Cytokine GM-CSF to Initiate and Augment Autoimmune Arthritis.

    Science.gov (United States)

    Hirota, Keiji; Hashimoto, Motomu; Ito, Yoshinaga; Matsuura, Mayumi; Ito, Hiromu; Tanaka, Masao; Watanabe, Hitomi; Kondoh, Gen; Tanaka, Atsushi; Yasuda, Keiko; Kopf, Manfred; Potocnik, Alexandre J; Stockinger, Brigitta; Sakaguchi, Noriko; Sakaguchi, Shimon

    2018-06-19

    Despite the importance of Th17 cells in autoimmune diseases, it remains unclear how they control other inflammatory cells in autoimmune tissue damage. Using a model of spontaneous autoimmune arthritis, we showed that arthritogenic Th17 cells stimulated fibroblast-like synoviocytes via interleukin-17 (IL-17) to secrete the cytokine GM-CSF and also expanded synovial-resident innate lymphoid cells (ILCs) in inflamed joints. Activated synovial ILCs, which expressed CD25, IL-33Ra, and TLR9, produced abundant GM-CSF upon stimulation by IL-2, IL-33, or CpG DNA. Loss of GM-CSF production by either ILCs or radio-resistant stromal cells prevented Th17 cell-mediated arthritis. GM-CSF production by Th17 cells augmented chronic inflammation but was dispensable for the initiation of arthritis. We showed that GM-CSF-producing ILCs were present in inflamed joints of rheumatoid arthritis patients. Thus, a cellular cascade of autoimmune Th17 cells, ILCs, and stromal cells, via IL-17 and GM-CSF, mediates chronic joint inflammation and can be a target for therapeutic intervention. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Differentiation of Human Adipose Derived Stem Cells into Smooth Muscle Cells Is Modulated by CaMKIIγ

    Directory of Open Access Journals (Sweden)

    Kaisaier Aji

    2016-01-01

    Full Text Available The multifunctional Ca2+/calmodulin-dependent protein kinase II (CaMKII is known to participate in maintenance and switches of smooth muscle cell (SMC phenotypes. However, which isoform of CaMKII is involved in differentiation of adult mesenchymal stem cells into contractile SMCs remains unclear. In the present study, we detected γ isoform of CaMKII in differentiation of human adipose derived stem cells (hASCs into SMCs that resulted from treatment with TGF-β1 and BMP4 in combination for 7 days. The results showed that CaMKIIγ increased gradually during differentiation of hASCs as determined by real-time PCR and western blot analysis. The siRNA-mediated knockdown of CaMKIIγ decreased the protein levels and transcriptional levels of smooth muscle contractile markers (a-SMA, SM22a, calponin, and SM-MHC, while CaMKIIγ overexpression increases the transcriptional and protein levels of smooth muscle contractile markers. These results suggested that γ isoform of CaMKII plays a significant role in smooth muscle differentiation of hASCs.

  16. [Product safety analysis of somatic cell cloned bovine].

    Science.gov (United States)

    Hua, Song; Lan, Jie; Song, Yongli; Lu, Chenglong; Zhang, Yong

    2010-05-01

    Somatic cell cloning (nuclear transfer) is a technique through which the nucleus (DNA) of a somatic cell is transferred into an enucleated oocyte for the generation of a new individual, genetically identical to the somatic cell donor. It could be applied for the enhancement of reproduction rate and the improvement of food products involving quality, yield and nutrition. In recent years, the United States, Japan and Europe as well as other countries announced that meat and milk products made from cloned cattle are safe for human consumption. Yet, cloned animals are faced with a wide range of health problems, with a high death rate and a high incidence of disease. The precise causal mechanisms for the low efficiency of cloning remain unclear. Is it safe that any products from cloned animals were allowed into the food supply? This review focuses on the security of meat, milk and products from cloned cattle based on the available data.

  17. Antimony trichloride induces a loss of cell viability via reactive oxygen species-dependent autophagy in A549 cells.

    Science.gov (United States)

    Zhao, Xinyuan; Xing, Fengjun; Cong, Yewen; Zhuang, Yin; Han, Muxi; Wu, Zhiqiang; Yu, Shali; Wei, Haiyan; Wang, Xiaoke; Chen, Gang

    2017-12-01

    Antimony (Sb) is one of the most prevalent heavy metals and frequently leads to biological toxicity. Although autophagy is believed to be involved in metal-associated cytotoxicity, there is no evidence of its involvement following exposure. Moreover, the underlying mechanism of autophagy remains unclear. In this study, treatment with antimony trichloride caused autophagy in a dose- and time-dependent manner in A549 cells but did not affect the level of Atg5 or Atg7 mRNA expression. Furthermore, Sb enhanced autophagic flux while upregulating p62 gene and protein levels. The classic mechanistic target of rapamycin (mTOR) pathway is not involved in Sb-induced autophagy. However, Sb-induced autophagy and the upregulation of p62 were inhibited by treatment with the antioxidant N-acetylcysteine (NAC). Subsequent analyses demonstrated that the inhibition of autophagy protected A549 cells from a loss of cell viability, while the activation of autophagy by rapamycin had the opposite effect. These data suggest that reactive oxygen species-dependent autophagy mediates Sb-stimulated cell viability loss in A549 cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. SPECT/spiral-CT hybrid imaging in unclear foci of increased bone metabolism: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Roemer, W.; Kuwert, T. [Nuklearmedizinische Klinik, Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany); Beckmann, M.W. [Frauenklinik, Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany); Forst, R. [Lehrstuhl fuer Orthopaedie mit Orthopaedischer Chirurgie, Friedrich-Alexander Univ. Erlangen/Nuernberg (Germany); Bautz, W. [Radiologisches Inst., Friedrich-Alexander-Univ. Erlangen/Nuernberg (Germany)

    2005-07-01

    In bone scintigraphy, the differentiation between degenerative processes and bone metastases is still difficult. Therefore, additional radiological studies are regularly needed after bone scintigraphy. The now introduced hybrid-cameras combining single-photon emission computed tomography (SPECT) and spiral-CT are unique in the sense that they offer the opportunity to correlate the functional information with morphology in one session. We herein present two patients in whom this technological setup allowed a definite diagnosis in scintigraphically unclear vertebral lesions. In a patient with breast cancer, hypermetabolic lesions were clearly correlated with osteolyses. In another patient with synovial carcinoma, spondylosis and spondylarthrosis caused focal tracer uptake in the lumbar spine. In addition to an improved diagnostic accuracy, SPECT/Spiral-CT will considerably abbreviate the diagnostic process. (orig.)

  19. SPECT/spiral-CT hybrid imaging in unclear foci of increased bone metabolism: a case report

    International Nuclear Information System (INIS)

    Roemer, W.; Kuwert, T.; Beckmann, M.W.; Forst, R.; Bautz, W.

    2005-01-01

    In bone scintigraphy, the differentiation between degenerative processes and bone metastases is still difficult. Therefore, additional radiological studies are regularly needed after bone scintigraphy. The now introduced hybrid-cameras combining single-photon emission computed tomography (SPECT) and spiral-CT are unique in the sense that they offer the opportunity to correlate the functional information with morphology in one session. We herein present two patients in whom this technological setup allowed a definite diagnosis in scintigraphically unclear vertebral lesions. In a patient with breast cancer, hypermetabolic lesions were clearly correlated with osteolyses. In another patient with synovial carcinoma, spondylosis and spondylarthrosis caused focal tracer uptake in the lumbar spine. In addition to an improved diagnostic accuracy, SPECT/Spiral-CT will considerably abbreviate the diagnostic process. (orig.)

  20. Science, ethics and communication remain essential for the success of cell-based therapies

    Directory of Open Access Journals (Sweden)

    Massimo Dominici

    2016-01-01

    Full Text Available Cell-based therapeutics, such as marrow or peripheral blood stem cell transplantation, are a standard of care for certain malignancies. More recently, a wider variety of cell-based therapeutics including the use of mesenchymal stromal/stem cells, T-cells, and others show great promise in a wider range of diseases. With increased efforts to expand cell-based treatments to several clinical settings, many institutions around the world have developed programs to explore cellular therapy's potential for safe and effective applications. In legitimate investigations, usually conducted through academic centers or biotechnology industry-sponsored efforts, these studies are regulated and peer-reviewed to ensure safety and clear determination of potential efficacy. However, in some cases, the use of cell-based approaches is conducted with insufficient preclinical data, scientific rationale, and/or study plan for the diseases claimed to be treated, with patients being charged for these services without clear evidence of clinical benefit. In this context, patients may not be properly informed regarding the exact treatment they are receiving within a consenting process that may not be completely valid or ethical. Here, the authors emphasize the importance of distinguishing “proven cell-based therapies” from “unproven” and unauthorized cell-based therapies. This publication also addresses the necessity for improved communication between the different stakeholders in the field, patient associations, and advocacy groups in particular, to favor medical innovation and provide legitimate benefits to patients. Considering the progressive growth of cell-based treatments, their increasing therapeutic value and the expectation that society has about these therapies, it is critically important to protect patients and ensure that the risk/benefit ratio is favorable. This paper is a review article. Literature referred to in this paper has been listed in the

  1. Hematopoietic Stem Cells Are the Major Source of Multilineage Hematopoiesis in Adult Animals.

    Science.gov (United States)

    Sawai, Catherine M; Babovic, Sonja; Upadhaya, Samik; Knapp, David J H F; Lavin, Yonit; Lau, Colleen M; Goloborodko, Anton; Feng, Jue; Fujisaki, Joji; Ding, Lei; Mirny, Leonid A; Merad, Miriam; Eaves, Connie J; Reizis, Boris

    2016-09-20

    Hematopoietic stem cells (HSCs) sustain long-term reconstitution of hematopoiesis in transplantation recipients, yet their role in the endogenous steady-state hematopoiesis remains unclear. In particular, recent studies suggested that HSCs provide a relatively minor contribution to immune cell development in adults. We directed transgene expression in a fraction of HSCs that maintained reconstituting activity during serial transplantations. Inducible genetic labeling showed that transgene-expressing HSCs gave rise to other phenotypic HSCs, confirming their top position in the differentiation hierarchy. The labeled HSCs rapidly contributed to committed progenitors of all lineages and to mature myeloid cells and lymphocytes, but not to B-1a cells or tissue macrophages. Importantly, labeled HSCs gave rise to more than two-thirds of all myeloid cells and platelets in adult mice, and this contribution could be accelerated by an induced interferon response. Thus, classically defined HSCs maintain immune cell development in the steady state and during systemic cytokine responses. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. NANOS2 acts downstream of glial cell line-derived neurotrophic factor signaling to suppress differentiation of spermatogonial stem cells.

    Science.gov (United States)

    Sada, Aiko; Hasegawa, Kazuteru; Pin, Pui Han; Saga, Yumiko

    2012-02-01

    Stem cells are maintained by both stem cell-extrinsic niche signals and stem cell-intrinsic factors. During murine spermatogenesis, glial cell line-derived neurotrophic factor (GDNF) signal emanated from Sertoli cells and germ cell-intrinsic factor NANOS2 represent key regulators for the maintenance of spermatogonial stem cells. However, it remains unclear how these factors intersect in stem cells to control their cellular state. Here, we show that GDNF signaling is essential to maintain NANOS2 expression, and overexpression of Nanos2 can alleviate the stem cell loss phenotype caused by the depletion of Gfra1, a receptor for GDNF. By using an inducible Cre-loxP system, we show that NANOS2 expression is downregulated upon the conditional knockout (cKO) of Gfra1, while ectopic expression of Nanos2 in GFRA1-negative spermatogonia does not induce de novo GFRA1 expression. Furthermore, overexpression of Nanos2 in the Gfra1-cKO testes prevents precocious differentiation of the Gfra1-knockout stem cells and partially rescues the stem cell loss phenotypes of Gfra1-deficient mice, indicating that the stem cell differentiation can be suppressed by NANOS2 even in the absence of GDNF signaling. Taken together, we suggest that NANOS2 acts downstream of GDNF signaling to maintain undifferentiated state of spermatogonial stem cells. Copyright © 2011 AlphaMed Press.

  3. Tributyltin induces G2/M cell cycle arrest via NAD(+)-dependent isocitrate dehydrogenase in human embryonic carcinoma cells.

    Science.gov (United States)

    Asanagi, Miki; Yamada, Shigeru; Hirata, Naoya; Itagaki, Hiroshi; Kotake, Yaichiro; Sekino, Yuko; Kanda, Yasunari

    2016-04-01

    Organotin compounds, such as tributyltin (TBT), are well-known endocrine-disrupting chemicals (EDCs). We have recently reported that TBT induces growth arrest in the human embryonic carcinoma cell line NT2/D1 at nanomolar levels by inhibiting NAD(+)-dependent isocitrate dehydrogenase (NAD-IDH), which catalyzes the irreversible conversion of isocitrate to α-ketoglutarate. However, the molecular mechanisms by which NAD-IDH mediates TBT toxicity remain unclear. In the present study, we examined whether TBT at nanomolar levels affects cell cycle progression in NT2/D1 cells. Propidium iodide staining revealed that TBT reduced the ratio of cells in the G1 phase and increased the ratio of cells in the G2/M phase. TBT also reduced cell division cycle 25C (cdc25C) and cyclin B1, which are key regulators of G2/M progression. Furthermore, apigenin, an inhibitor of NAD-IDH, mimicked the effects of TBT. The G2/M arrest induced by TBT was abolished by NAD-IDHα knockdown. Treatment with a cell-permeable α-ketoglutarate analogue recovered the effect of TBT, suggesting the involvement of NAD-IDH. Taken together, our data suggest that TBT at nanomolar levels induced G2/M cell cycle arrest via NAD-IDH in NT2/D1 cells. Thus, cell cycle analysis in embryonic cells could be used to assess cytotoxicity associated with nanomolar level exposure of EDCs.

  4. E1(-)E4(+) adenoviral gene transfer vectors function as a "pro-life" signal to promote survival of primary human endothelial cells.

    Science.gov (United States)

    Ramalingam, R; Rafii, S; Worgall, S; Brough, D E; Crystal, R G

    1999-05-01

    Although endothelial cells are quiescent and long-lived in vivo, when they are removed from blood vessels and cultured in vitro they die within days to weeks. In studies of the interaction of E1(-)E4(+) replication-deficient adenovirus (Ad) vectors and human endothelium, the cells remained quiescent and were viable for prolonged periods. Evaluation of these cultures showed that E1(-)E4(+) Ad vectors provide an "antiapoptotic" signal that, in association with an increase in the ratio of Bcl2 to Bax levels, induces the endothelial cells to enter a state of "suspended animation," remaining viable for at least 30 days, even in the absence of serum and growth factors. Although the mechanisms initiating these events are unclear, the antiapoptoic signal requires the presence of E4 genes in the vector genome, suggesting that one or more E4 open reading frames of subgroup C Ad initiate a "pro-life" program that modifies cultured endothelial cells to survive for prolonged periods.

  5. Dickkopf1 Up-Regulation Induced by a High Concentration of Dexamethasone Promotes Rat Tendon Stem Cells to Differentiate Into Adipocytes

    OpenAIRE

    Wan Chen; Hong Tang; Xiangzhou Liu; Mei Zhou; Jiqiang Zhang; Kanglai Tang

    2015-01-01

    Background/Aims: Dexamethasone (Dex)-induced spontaneous tendon rupture and decreased self-repair capability is very common in clinical practice. The metaplasia of adipose tissue in the ruptured tendon indicates that Dex may induce tendon stem cells (TSCs) to differentiate into adipocytes, but the mechanism remains unclear. In the present study, we used in vitro methods to investigate the effects of Dex on rat TSC differentiation and the molecular mechanisms underlying this process. Methods: ...

  6. Determinants of cell-to-cell variability in protein kinase signaling.

    Directory of Open Access Journals (Sweden)

    Matthias Jeschke

    Full Text Available Cells reliably sense environmental changes despite internal and external fluctuations, but the mechanisms underlying robustness remain unclear. We analyzed how fluctuations in signaling protein concentrations give rise to cell-to-cell variability in protein kinase signaling using analytical theory and numerical simulations. We characterized the dose-response behavior of signaling cascades by calculating the stimulus level at which a pathway responds ('pathway sensitivity' and the maximal activation level upon strong stimulation. Minimal kinase cascades with gradual dose-response behavior show strong variability, because the pathway sensitivity and the maximal activation level cannot be simultaneously invariant. Negative feedback regulation resolves this trade-off and coordinately reduces fluctuations in the pathway sensitivity and maximal activation. Feedbacks acting at different levels in the cascade control different aspects of the dose-response curve, thereby synergistically reducing the variability. We also investigated more complex, ultrasensitive signaling cascades capable of switch-like decision making, and found that these can be inherently robust to protein concentration fluctuations. We describe how the cell-to-cell variability of ultrasensitive signaling systems can be actively regulated, e.g., by altering the expression of phosphatase(s or by feedback/feedforward loops. Our calculations reveal that slow transcriptional negative feedback loops allow for variability suppression while maintaining switch-like decision making. Taken together, we describe design principles of signaling cascades that promote robustness. Our results may explain why certain signaling cascades like the yeast pheromone pathway show switch-like decision making with little cell-to-cell variability.

  7. Early appearance of germinal center–derived memory B cells and plasma cells in blood after primary immunization

    Science.gov (United States)

    Blink, Elizabeth J.; Light, Amanda; Kallies, Axel; Nutt, Stephen L.; Hodgkin, Philip D.; Tarlinton, David M.

    2005-01-01

    Immunization with a T cell–dependent antigen elicits production of specific memory B cells and antibody-secreting cells (ASCs). The kinetic and developmental relationships between these populations and the phenotypic forms they and their precursors may take remain unclear. Therefore, we examined the early stages of a primary immune response, focusing on the appearance of antigen-specific B cells in blood. Within 1 wk, antigen-specific B cells appear in the blood with either a memory phenotype or as immunoglobulin (Ig)G1 ASCs expressing blimp-1. The memory cells have mutated VH genes; respond to the chemokine CXCL13 but not CXCL12, suggesting recirculation to secondary lymphoid organs; uniformly express B220; show limited differentiation potential unless stimulated by antigen; and develop independently of blimp-1 expression. The antigen-specific IgG1 ASCs in blood show affinity maturation paralleling that of bone marrow ASCs, raising the possibility that this compartment is established directly by blood-borne ASCs. We find no evidence for a blimp-1–expressing preplasma memory compartment, suggesting germinal center output is restricted to ASCs and B220+ memory B cells, and this is sufficient to account for the process of affinity maturation. PMID:15710653

  8. [Impact of postoperative pathological features of esophageal squamous cell carcinoma on the prognosis].

    Science.gov (United States)

    Xu, Lei; Li, Yin; Sun, Haibo; Zheng, Yan; Wang, Zongfei; Chen, Xiankai

    2017-12-25

    Esophageal cancer is located in the 8th position of the incidence of malignant tumors and the 6th most common cause of cancer-related mortality in the world, while China has the highest incidence and mortality of esophageal cancer. Esophageal squamous cell carcinoma (ESCC), the predominant histologic type of esophageal cancer in China, accounts for about 90%. Despite recent improvement of surgical techniques and philosophy, however, the prognosis of ESCC patients treated with surgery is still poor, and 5-year survival remains unsatisfactorily low. So far, the pathogenesis of esophageal squamous cell carcinoma is still unclear, and effective prevention is also out of the question. To find the main factors affecting the prognosis of esophageal squamous cell carcinoma, and to improve the survival of patients, are the main directions of all scholars. Postoperative pathology of esophageal squamous cell carcinoma is considered to be one of the most important predictors of prognosis. Currently, the evaluation of postoperative esophageal prognosis mainly depends on TNM staging, but some criteria of its specific content and staging remains controversial. In this paper recent domestic and foreign related researches and clinical trials reports are collected, and the postoperative pathological features affecting esophageal squamous cell carcinoma prognosis were reviewed.

  9. Simulated microgravity, Mars gravity, and 2g hypergravity affect cell cycle regulation, ribosome biogenesis, and epigenetics in Arabidopsis cell cultures.

    Science.gov (United States)

    Kamal, Khaled Y; Herranz, Raúl; van Loon, Jack J W A; Medina, F Javier

    2018-04-23

    Gravity is the only component of Earth environment that remained constant throughout the entire process of biological evolution. However, it is still unclear how gravity affects plant growth and development. In this study, an in vitro cell culture of Arabidopsis thaliana was exposed to different altered gravity conditions, namely simulated reduced gravity (simulated microgravity, simulated Mars gravity) and hypergravity (2g), to study changes in cell proliferation, cell growth, and epigenetics. The effects after 3, 14, and 24-hours of exposure were evaluated. The most relevant alterations were found in the 24-hour treatment, being more significant for simulated reduced gravity than hypergravity. Cell proliferation and growth were uncoupled under simulated reduced gravity, similarly, as found in meristematic cells from seedlings grown in real or simulated microgravity. The distribution of cell cycle phases was changed, as well as the levels and gene transcription of the tested cell cycle regulators. Ribosome biogenesis was decreased, according to levels and gene transcription of nucleolar proteins and the number of inactive nucleoli. Furthermore, we found alterations in the epigenetic modifications of chromatin. These results show that altered gravity effects include a serious disturbance of cell proliferation and growth, which are cellular functions essential for normal plant development.

  10. A rare subset of skin-tropic regulatory T cells expressing Il10/Gzmb inhibits the cutaneous immune response.

    Science.gov (United States)

    Ikebuchi, Ryoyo; Teraguchi, Shunsuke; Vandenbon, Alexis; Honda, Tetsuya; Shand, Francis H W; Nakanishi, Yasutaka; Watanabe, Takeshi; Tomura, Michio

    2016-10-19

    Foxp3 + regulatory T cells (Tregs) migrating from the skin to the draining lymph node (dLN) have a strong immunosuppressive effect on the cutaneous immune response. However, the subpopulations responsible for their inhibitory function remain unclear. We investigated single-cell gene expression heterogeneity in Tregs from the dLN of inflamed skin in a contact hypersensitivity model. The immunosuppressive genes Ctla4 and Tgfb1 were expressed in the majority of Tregs. Although Il10-expressing Tregs were rare, unexpectedly, the majority of Il10-expressing Tregs co-expressed Gzmb and displayed Th1-skewing. Single-cell profiling revealed that CD43 + CCR5 + Tregs represented the main subset within the Il10/Gzmb-expressing cell population in the dLN. Moreover, CD43 + CCR5 + CXCR3 - Tregs expressed skin-tropic chemokine receptors, were preferentially retained in inflamed skin and downregulated the cutaneous immune response. The identification of a rare Treg subset co-expressing multiple immunosuppressive molecules and having tissue-remaining capacity offers a novel strategy for the control of skin inflammatory responses.

  11. Ionotropic Receptor-dependent moist and dry cells control hygrosensation in Drosophila.

    Science.gov (United States)

    Knecht, Zachary A; Silbering, Ana F; Cruz, Joyner; Yang, Ludi; Croset, Vincent; Benton, Richard; Garrity, Paul A

    2017-06-16

    Insects use hygrosensation (humidity sensing) to avoid desiccation and, in vectors such as mosquitoes, to locate vertebrate hosts. Sensory neurons activated by either dry or moist air ('dry cells' and 'moist cells') have been described in many insects, but their behavioral roles and the molecular basis of their hygrosensitivity remain unclear. We recently reported that Drosophila hygrosensation relies on three Ionotropic Receptors (IRs) required for dry cell function: IR25a, IR93a and IR40a (Knecht et al., 2016). Here, we discover Drosophila moist cells and show that they require IR25a and IR93a together with IR68a, a conserved, but orphan IR. Both IR68a- and IR40a-dependent pathways drive hygrosensory behavior: each is important for dry-seeking by hydrated flies and together they underlie moist-seeking by dehydrated flies. These studies reveal that humidity sensing in Drosophila , and likely other insects, involves the combined activity of two molecularly related but neuronally distinct hygrosensing systems.

  12. Vaccination Expands Antigen-Specific CD4+ Memory T Cells and Mobilizes Bystander Central Memory T Cells

    Science.gov (United States)

    Li Causi, Eleonora; Parikh, Suraj C.; Chudley, Lindsey; Layfield, David M.; Ottensmeier, Christian H.; Stevenson, Freda K.; Di Genova, Gianfranco

    2015-01-01

    CD4+ T helper memory (Thmem) cells influence both natural and vaccine-boosted immunity, but mechanisms for their maintenance remain unclear. Pro-survival signals from the common gamma-chain cytokines, in particular IL-7, appear important. Previously we showed in healthy volunteers that a booster vaccination with tetanus toxoid (TT) expanded peripheral blood TT-specific Thmem cells as expected, but was accompanied by parallel increase of Thmem cells specific for two unrelated and non cross-reactive common recall antigens. Here, in a new cohort of healthy human subjects, we compare blood vaccine-specific and bystander Thmem cells in terms of differentiation stage, function, activation and proliferative status. Both responses peaked 1 week post-vaccination. Vaccine-specific cytokine-producing Thmem cells were predominantly effector memory, whereas bystander cells were mainly of central memory phenotype. Importantly, TT-specific Thmem cells were activated (CD38High HLA-DR+), cycling or recently divided (Ki-67+), and apparently vulnerable to death (IL-7RαLow and Bcl-2 Low). In contrast, bystander Thmem cells were resting (CD38Low HLA-DR- Ki-67-) with high expression of IL-7Rα and Bcl-2. These findings allow a clear distinction between vaccine-specific and bystander Thmem cells, suggesting the latter do not derive from recent proliferation but from cells mobilized from as yet undefined reservoirs. Furthermore, they reveal the interdependent dynamics of specific and bystander T-cell responses which will inform assessments of responses to vaccines. PMID:26332995

  13. Cross-Generational Reproductive Fitness Enforced by Microchimeric Maternal Cells.

    Science.gov (United States)

    Kinder, Jeremy M; Jiang, Tony T; Ertelt, James M; Xin, Lijun; Strong, Beverly S; Shaaban, Aimen F; Way, Sing Sing

    2015-07-30

    Exposure to maternal tissue during in utero development imprints tolerance to immunologically foreign non-inherited maternal antigens (NIMA) that persists into adulthood. The biological advantage of this tolerance, conserved across mammalian species, remains unclear. Here, we show maternal cells that establish microchimerism in female offspring during development promote systemic accumulation of immune suppressive regulatory T cells (Tregs) with NIMA specificity. NIMA-specific Tregs expand during pregnancies sired by males expressing alloantigens with overlapping NIMA specificity, thereby averting fetal wastage triggered by prenatal infection and non-infectious disruptions of fetal tolerance. Therefore, exposure to NIMA selectively enhances reproductive success in second-generation females carrying embryos with overlapping paternally inherited antigens. These findings demonstrate that genetic fitness, canonically thought to be restricted to Mendelian inheritance, is enhanced in female placental mammals through vertically transferred maternal cells that promote conservation of NIMA and enforce cross-generational reproductive benefits. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. T Follicular Helper-Like Cells Are Involved in the Pathogenesis of Experimental Autoimmune Encephalomyelitis

    Directory of Open Access Journals (Sweden)

    Jun Guo

    2018-05-01

    Full Text Available Multiple sclerosis (MS and experimental autoimmune encephalomyelitis (EAE have been proved to be T cell-mediated autoimmune diseases. Recent researches indicate that humoral immunity is also involved in the pathogenesis of these disorders. T follicular helper (Tfh cells are critical for B cell differentiation and antibody production. However, the role of Tfh cells in MS and EAE remains unclear. Here, we found elevated frequencies of CD4+CXCR5+PD-1+ Tfh-like cells in both MS patients and EAE. In EAE mice, Tfh-like cells, together with B cells, were found in the ectopic lymphoid structures in spinal cords. Moreover, Tfh-like cells promoted the antibody production via IL-21/IL-21R and CD40 ligand/CD40 interaction and the synergy effect of STAT3 and non-canonical NF-κB signaling pathway inside B cells. Moreover, adoptive transfer of Tfh-like cells could increase the severity and delay the remission of EAE. In conclusion, our data indicate that Tfh-like cells contribute to the pathogenesis of EAE.

  15. Downregulation of HDAC9 inhibits cell proliferation and tumor formation by inducing cell cycle arrest in retinoblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yiting; Wu, Dan; Xia, Fengjie; Xian, Hongyu; Zhu, Xinyue [Medical School of Nanjing University, Department of Ophthalmology, Jinling Hospital, Nanjing, 210002 (China); Cui, Hongjuan, E-mail: hcui@swu.edu.cn [State Key Laboratory of Silkworm Genome Biology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, 400716 (China); Huang, Zhenping, E-mail: huangzhenping19633@163.com [Medical School of Nanjing University, Department of Ophthalmology, Jinling Hospital, Nanjing, 210002 (China)

    2016-04-29

    Histone deacetylase 9 (HDAC9) is a member of class II HDACs, which regulates a wide variety of normal and abnormal physiological functions. Recently, HDAC9 has been found to be overexpressed in some types of human cancers. However, the role of HDAC9 in retinoblastoma remains unclear. In this study, we found that HDAC9 was commonly expressed in retinoblastoma tissues and HDAC9 was overexpressed in prognostically poor retinoblastoma patients. Through knocking down HDAC9 in Y79 and WERI-Rb-1 cells, the expression level of HDAC9 was found to be positively related to cell proliferation in vitro. Further investigation indicated that knockdown HDAC9 could significantly induce cell cycle arrest at G1 phase in retinoblastoma cells. Western blot assay showed downregulation of HDAC9 could significantly decrease cyclin E2 and CDK2 expression. Lastly, xenograft study in nude mice showed that downregulation of HDAC9 inhibited tumor growth and development in vivo. Therefore, our results suggest that HDAC9 could serve as a novel potential therapeutic target in the treatment of retinoblastoma. - Highlights: • High expression of HDAC9 correlates with poor patient prognosis. • Downregulation of HDAC9 inhibits cell proliferation in retinoblastoma cells. • Downregulation of HDAC9 induces cell cycle arrest at G1 phase in retinoblastoma cells. • Downregulation of HDAC9 suppresses tumor growth in nude mice.

  16. Engineering of Systematic Elimination of a Targeted Chromosome in Human Cells.

    Science.gov (United States)

    Sato, Hiroshi; Kato, Hiroki; Yamaza, Haruyoshi; Masuda, Keiji; Nguyen, Huong Thi Nguyen; Pham, Thanh Thi Mai; Han, Xu; Hirofuji, Yuta; Nonaka, Kazuaki

    2017-01-01

    Embryonic trisomy leads to abortion or congenital genetic disorders in humans. The most common autosomal chromosome abnormalities are trisomy of chromosomes 13, 18, and 21. Although alteration of gene dosage is thought to contribute to disorders caused by extra copies of chromosomes, genes associated with specific disease phenotypes remain unclear. To generate a normal cell from a trisomic cell as a means of etiological analysis or candidate therapy for trisomy syndromes, we developed a system to eliminate a targeted chromosome from human cells. Chromosome 21 was targeted by integration of a DNA cassette in HeLa cells that harbored three copies of chromosome 21. The DNA cassette included two inverted loxP sites and a herpes simplex virus thymidine kinase (HSV-tk) gene. This system causes missegregation of chromosome 21 after expression of Cre recombinase and subsequently enables the selection of cells lacking the chromosome by culturing in a medium that includes ganciclovir (GCV). Cells harboring only two copies of chromosome 21 were efficiently induced by transfection of a Cre expression vector, indicating that this approach is useful for eliminating a targeted chromosome.

  17. Lactic acid in tumor microenvironments causes dysfunction of NKT cells by interfering with mTOR signaling.

    Science.gov (United States)

    Xie, Di; Zhu, Shasha; Bai, Li

    2016-12-01

    Cellular metabolism has been shown to regulate differentiation and function of immune cells. Tumor associated immune cells undergo phenotypic and functional alterations due to the change of cellular metabolism in tumor microenvironments. NKT cells are good candidates for immunotherapies against tumors and have been used in several clinical trials. However, the influences of tumor microenvironments on NKT cell functions remain unclear. In our studies, lactic acid in tumor microenvironments inhibited IFNγ and IL4 productions from NKT cells, and more profound influence on IFNγ was observed. By adjusting the pH of culture medium we further showed that, dysfunction of NKT cells could simply be induced by low extracellular pH. Moreover, low extracellular pH inhibited NKT cell functions by inhibiting mammalian target of rapamycin (mTOR) signaling and nuclear translocation of promyelocytic leukemia zinc-finger (PLZF). Together, our results suggest that tumor acidic microenvironments could interfere with NKT cell functions through metabolic controls.

  18. GTSE1 is a microtubule plus-end tracking protein that regulates EB1-dependent cell migration.

    Directory of Open Access Journals (Sweden)

    Massimilano Scolz

    Full Text Available The regulation of cell migration is a highly complex process that is often compromised when cancer cells become metastatic. The microtubule cytoskeleton is necessary for cell migration, but how microtubules and microtubule-associated proteins regulate multiple pathways promoting cell migration remains unclear. Microtubule plus-end binding proteins (+TIPs are emerging as important players in many cellular functions, including cell migration. Here we identify a +TIP, GTSE1, that promotes cell migration. GTSE1 accumulates at growing microtubule plus ends through interaction with the EB1+TIP. The EB1-dependent +TIP activity of GTSE1 is required for cell migration, as well as for microtubule-dependent disassembly of focal adhesions. GTSE1 protein levels determine the migratory capacity of both nontransformed and breast cancer cell lines. In breast cancers, increased GTSE1 expression correlates with invasive potential, tumor stage, and time to distant metastasis, suggesting that misregulation of GTSE1 expression could be associated with increased invasive potential.

  19. B cells negatively regulate the establishment of CD49b+T-bet+ resting memory T helper cells in the bone marrow

    Directory of Open Access Journals (Sweden)

    Shintaro eHojyo

    2016-02-01

    Full Text Available During an immune reaction, some antigen-experienced CD4 T cells relocate from secondary lymphoid organs (SLOs to the bone marrow (BM in a CD49b-dependent manner and reside and rest there as professional memory CD4 T cells. However, it remains unclear how the precursors of BM memory CD4 T cells are generated in the SLOs. While several studies have so far shown that B cell depletion reduces the persistence of memory CD4 T cells in the spleen, we here show that B cell depletion enhances the establishment of memory CD4 T cells in the BM and that B cell transfer conversely suppresses it. Interestingly, the number of antigen-experienced CD4 T cells in the BM synchronizes the number of CD49b+T-bet+ antigen-experienced CD4 T cells in the spleen. CD49b+T-bet+ antigen-experienced CD4 T cells preferentially localize in the red pulp area of the spleen and the BM in a T-bet-independent manner. We suggest that B cells negatively control the generation of CD49b+T-bet+ precursors of resting memory CD4 T cells in the spleen and may play a role in bifurcation of activated effector and resting memory CD4 T cell lineages.

  20. Distinct epigenomic landscapes of pluripotent and lineage-committed human cells.

    Science.gov (United States)

    Hawkins, R David; Hon, Gary C; Lee, Leonard K; Ngo, Queminh; Lister, Ryan; Pelizzola, Mattia; Edsall, Lee E; Kuan, Samantha; Luu, Ying; Klugman, Sarit; Antosiewicz-Bourget, Jessica; Ye, Zhen; Espinoza, Celso; Agarwahl, Saurabh; Shen, Li; Ruotti, Victor; Wang, Wei; Stewart, Ron; Thomson, James A; Ecker, Joseph R; Ren, Bing

    2010-05-07

    Human embryonic stem cells (hESCs) share an identical genome with lineage-committed cells, yet possess the remarkable properties of self-renewal and pluripotency. The diverse cellular properties in different cells have been attributed to their distinct epigenomes, but how much epigenomes differ remains unclear. Here, we report that epigenomic landscapes in hESCs and lineage-committed cells are drastically different. By comparing the chromatin-modification profiles and DNA methylomes in hESCs and primary fibroblasts, we find that nearly one-third of the genome differs in chromatin structure. Most changes arise from dramatic redistributions of repressive H3K9me3 and H3K27me3 marks, which form blocks that significantly expand in fibroblasts. A large number of potential regulatory sequences also exhibit a high degree of dynamics in chromatin modifications and DNA methylation. Additionally, we observe novel, context-dependent relationships between DNA methylation and chromatin modifications. Our results provide new insights into epigenetic mechanisms underlying properties of pluripotency and cell fate commitment.

  1. Tight coupling between nucleus and cell migration through the perinuclear actin cap

    Science.gov (United States)

    Kim, Dong-Hwee; Cho, Sangkyun; Wirtz, Denis

    2014-01-01

    ABSTRACT Although eukaryotic cells are known to alternate between ‘advancing’ episodes of fast and persistent movement and ‘hesitation’ episodes of low speed and low persistence, the molecular mechanism that controls the dynamic changes in morphology, speed and persistence of eukaryotic migratory cells remains unclear. Here, we show that the movement of the interphase nucleus during random cell migration switches intermittently between two distinct modes – rotation and translocation – that follow with high fidelity the sequential rounded and elongated morphologies of the nucleus and cell body, respectively. Nuclear rotation and translocation mediate the stop-and-go motion of the cell through the dynamic formation and dissolution, respectively, of the contractile perinuclear actin cap, which is dynamically coupled to the nuclear lamina and the nuclear envelope through LINC complexes. A persistent cell movement and nuclear translocation driven by the actin cap are halted following the disruption of the actin cap, which in turn allows the cell to repolarize for its next persistent move owing to nuclear rotation mediated by cytoplasmic dynein light intermediate chain 2. PMID:24639463

  2. Suppression of Cpn10 increases mitochondrial fission and dysfunction in neuroblastoma cells.

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    So Jung Park

    Full Text Available To date, several regulatory proteins involved in mitochondrial dynamics have been identified. However, the precise mechanism coordinating these complex processes remains unclear. Mitochondrial chaperones regulate mitochondrial function and structure. Chaperonin 10 (Cpn10 interacts with heat shock protein 60 (HSP60 and functions as a co-chaperone. In this study, we found that down-regulation of Cpn10 highly promoted mitochondrial fragmentation in SK-N-MC and SH-SY5Y neuroblastoma cells. Both genetic and chemical inhibition of Drp1 suppressed the mitochondrial fragmentation induced by Cpn10 reduction. Reactive oxygen species (ROS generation in 3-NP-treated cells was markedly enhanced by Cpn10 knock down. Depletion of Cpn10 synergistically increased cell death in response to 3-NP treatment. Furthermore, inhibition of Drp1 recovered Cpn10-mediated mitochondrial dysfunction in 3-NP-treated cells. Moreover, an ROS scavenger suppressed cell death mediated by Cpn10 knockdown in 3-NP-treated cells. Taken together, these results showed that down-regulation of Cpn10 increased mitochondrial fragmentation and potentiated 3-NP-mediated mitochondrial dysfunction in neuroblastoma cells.

  3. Combined modeling of cell aggregation and adhesion mediated by receptor–ligand interactions under shear flow

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    Yu Du

    2015-11-01

    Full Text Available Blood cell aggregation and adhesion to endothelial cells under shear flow are crucial to many biological processes such as thrombi formation, inflammatory cascade, and tumor metastasis, in which these cellular interactions are mainly mediated by the underlying receptor–ligand bindings. While theoretical modeling of aggregation dynamics and adhesion kinetics of interacting cells have been well studied separately, how to couple these two processes remains unclear. Here we develop a combined model that couples cellular aggregation dynamics and adhesion kinetics under shear flow. The impacts of shear rate (or shear stress and molecular binding affinity were elucidated. This study provides a unified model where the action of a fluid flow drives cell aggregation and adhesion under the modulations of the mechanical shear flow and receptor–ligand interaction kinetics. It offers an insight into understanding the relevant biological processes and functions.

  4. IL-10 and IL-27 producing dendritic cells capable of enhancing IL-10 production of T cells are induced in oral tolerance.

    Science.gov (United States)

    Shiokawa, Aya; Tanabe, Kosuke; Tsuji, Noriko M; Sato, Ryuichiro; Hachimura, Satoshi

    2009-06-30

    Oral tolerance is a key feature of intestinal immunity, generating systemic tolerance to ingested antigens (Ag). Dendritic cells (DC) have been revealed as important immune regulators, however, the precise role of DC in oral tolerance induction remains unclear. We investigated the characteristics of DC in spleen, mesenteric lymph node (MLN), and Peyer's patch (PP) after oral Ag administration in a TCR-transgenic mouse model. DC from PP and MLN of tolerized mice induced IL-10 production but not Foxp3 expression in cocultured T cells. IL-10 production was markedly increased after 5-7-day Ag administration especially in PP DC. On the other hand, IL-27 production was increased after 2-5-day Ag administration. CD11b(+) DC, which increased after ingestion of Ag, prominently expressed IL-10 and IL-27 compared with CD11b(-) DC. These results suggest that IL-10 and IL-27 producing DC are increased by interaction with antigen specific T cells in PP, and these DC act as an inducer of IL-10 producing T cells in oral tolerance.

  5. Mast cells dysregulate apoptotic and cell cycle genes in mucosal squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Davis Paul

    2006-12-01

    Full Text Available Abstract Background Mucosal squamous cell carcinoma of the head and neck is a disease of high mortality and morbidity. Interactions between the squamous cell carcinoma and the host's local immunity, and how the latter contributes to the biological behavior of the tumor are unclear. In vivo studies have demonstrated sequential mast cell infiltration and degranulation during squamous cell carcinogenesis. The degree of mast cell activation correlates closely with distinct phases of hyperkeratosis, dysplasia, carcinoma in-situ and invasive carcinoma. However, the role of mast cells in carcinogenesis is unclear. Aim This study explores the effects of mast cells on the proliferation and gene expression profile of mucosal squamous cell carcinoma using human mast cell line (HMC-1 and human glossal squamous cell carcinoma cell line (SCC25. Methods HMC-1 and SCC25 were co-cultured in a two-compartment chamber, separated by a polycarbonate membrane. HMC-1 was stimulated to degranulate with calcium ionophore A23187. The experiments were done in quadruplicate. Negative controls were established where SCC25 were cultured alone without HMC-1. At 12, 24, 48 and 72 hours, proliferation and viability of SCC25 were assessed with MTT colorimetric assay. cDNA microarray was employed to study differential gene expression between co-cultured and control SCC25. Results HMC-1/SCC25 co-culture resulted in suppression of growth rate for SCC-25 (34% compared with 110% for the control by 72 hours, p Conclusion We show that mast cells have a direct inhibitory effect on the proliferation of mucosal squamous cell carcinoma in vitro by dysregulating key genes in apoptosis and cell cycle control.

  6. 2B4-SAP signaling is required for the priming of naive CD8+ T cells by antigen-expressing B cells and B lymphoma cells.

    Science.gov (United States)

    Huang, Yu-Hsuan; Tsai, Kevin; Tan, Sara Y; Kang, Sohyeong; Ford, Mandy L; Harder, Kenneth W; Priatel, John J

    2017-01-01

    Mutations in SH2D1A gene that encodes SAP (SLAM-associated protein) result in X-linked lymphoproliferative disease (XLP), a rare primary immunodeficiency disease defined by exquisite sensitivity to the B-lymphotropic Epstein-Barr virus (EBV) and B cell lymphomas. However, the precise mechanism of how the loss of SAP function contributes to extreme vulnerability to EBV and the development of B cell lymphomas remains unclear. Here, we investigate the hypothesis that SAP is critical for CD8 + T cell immune surveillance of antigen (Ag)-expressing B cells or B lymphoma cells under conditions of defined T cell receptor (TCR) signaling. Sh2d1a - / - CD8 + T cells exhibited greatly diminished proliferation relative to wild type when Ag-presenting-B cells or -B lymphoma cells served as the primary Ag-presenting cell (APC). By contrast, Sh2d1a - / - CD8 + T cells responded equivalently to wild-type CD8 + T cells when B cell-depleted splenocytes, melanoma cells or breast carcinoma cells performed Ag presentation. Through application of signaling lymphocyte activation molecule (SLAM) family receptor blocking antibodies or SLAM family receptor-deficient CD8 + T cells and APCs, we found that CD48 engagement on the B cell surface by 2B4 is crucial for initiating SAP-dependent signaling required for the Ag-driven CD8 + T cell proliferation and differentiation. Altogether, a pivotal role for SAP in promoting the expansion and differentiation of B cell-primed viral-specific naive CD8 + T cells may explain the selective immune deficiency of XLP patients to EBV and B cell lymphomas.

  7. 2B4-SAP signaling is required for the priming of naive CD8+ T cells by antigen-expressing B cells and B lymphoma cells

    Science.gov (United States)

    2017-01-01

    ABSTRACT Mutations in SH2D1A gene that encodes SAP (SLAM-associated protein) result in X-linked lymphoproliferative disease (XLP), a rare primary immunodeficiency disease defined by exquisite sensitivity to the B-lymphotropic Epstein–Barr virus (EBV) and B cell lymphomas. However, the precise mechanism of how the loss of SAP function contributes to extreme vulnerability to EBV and the development of B cell lymphomas remains unclear. Here, we investigate the hypothesis that SAP is critical for CD8+ T cell immune surveillance of antigen (Ag)-expressing B cells or B lymphoma cells under conditions of defined T cell receptor (TCR) signaling. Sh2d1a−/− CD8+ T cells exhibited greatly diminished proliferation relative to wild type when Ag-presenting-B cells or -B lymphoma cells served as the primary Ag-presenting cell (APC). By contrast, Sh2d1a−/− CD8+ T cells responded equivalently to wild-type CD8+ T cells when B cell-depleted splenocytes, melanoma cells or breast carcinoma cells performed Ag presentation. Through application of signaling lymphocyte activation molecule (SLAM) family receptor blocking antibodies or SLAM family receptor-deficient CD8+ T cells and APCs, we found that CD48 engagement on the B cell surface by 2B4 is crucial for initiating SAP-dependent signaling required for the Ag-driven CD8+ T cell proliferation and differentiation. Altogether, a pivotal role for SAP in promoting the expansion and differentiation of B cell-primed viral-specific naive CD8+ T cells may explain the selective immune deficiency of XLP patients to EBV and B cell lymphomas. PMID:28344876

  8. The Janus-faced roles of Krüppel-like factor 4 in oral squamous cell carcinoma cells.

    Science.gov (United States)

    Li, Wenwen; Liu, Man; Su, Ying; Zhou, Xinying; Liu, Yao; Zhang, Xinyan

    2015-12-29

    Krüppel-like factor 4 (KLF4) is a zinc-finger transcription factor that regulates many essential processes, including development and cell differentiation, proliferation, and apoptosis. Along with these roles in normal cells and tissues, KLF4 has important tumor suppressive and oncogenic functions in some malignancies. However, the roles of KLF4 in oral squamous cell carcinoma remain unclear. This study investigated the epigenetic alterations and possible roles of KLF4 in oral cancer carcinogenesis. Notably, KLF4 expression was significantly decreased in human oral cancer tissues compared with healthy controls, and KLF4 promoter hypermethylation contributed to the suppression of KLF4 expression. KLF4 expression was associated with tumor grade. Its expression was much lower in poorly differentiated oral cancers than in well-differentiated cancer cells. KLF4 exerted its antitumor activity in vitro and/or in vivo by inhibiting cell proliferation, cell cycle progression, cell colony formation and by inducing apoptosis. In addition, KLF4 over-expression promoted oral cancer cell migration and invasion in vitro. Knockdown of KLF4 promoted oral cancer cells growth and colony formation, and simultaneously inhibited cell migration and invasion. Mechanistic studies revealed that MMP-9 might contribute to KLF4-mediated cell migration and invasion. These results provide evidence that KLF4 might play Janus-faced roles in oral cancer carcinogenesis, acting both as a tumor suppressor and as an oncogene.

  9. Effects of electrical stimulation on cell proliferation and apoptosis.

    Science.gov (United States)

    Love, Maria R; Palee, Siripong; Chattipakorn, Siriporn C; Chattipakorn, Nipon

    2018-03-01

    The application of exogenous electrical stimulation (ES) to cells in order to manipulate cell apoptosis and proliferation has been widely investigated as a possible method of treatment in a number of diseases. Alteration of the transmembrane potential of cells via ES can affect various intracellular signaling pathways which are involved in the regulation of cellular function. Controversially, several types of ES have proved to be effective in both inhibiting or inducing apoptosis, as well as increasing proliferation. However, the mechanisms through which ES achieves this remain fairly unclear. The aim of this review was to comprehensively summarize current findings from in vitro and in vivo studies on the effects of different types of ES on cell apoptosis and proliferation, highlighting the possible mechanisms through which ES induced these effects and define the optimum parameters at which ES can be used. Through this we hope to provide a greater insight into how future studies can most effectively use ES at the clinical trial stage. © 2017 Wiley Periodicals, Inc.

  10. Selected microRNAs define cell fate determination of murine central memory CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Gonzalo Almanza

    2010-06-01

    Full Text Available During an immune response T cells enter memory fate determination, a program that divides them into two main populations: effector memory and central memory T cells. Since in many systems protection appears to be preferentially mediated by T cells of the central memory it is important to understand when and how fate determination takes place. To date, cell intrinsic molecular events that determine their differentiation remains unclear. MicroRNAs are a class of small, evolutionarily conserved RNA molecules that negatively regulate gene expression, causing translational repression and/or messenger RNA degradation. Here, using an in vitro system where activated CD8 T cells driven by IL-2 or IL-15 become either effector memory or central memory cells, we assessed the role of microRNAs in memory T cell fate determination. We found that fate determination to central memory T cells is under the balancing effects of a discrete number of microRNAs including miR-150, miR-155 and the let-7 family. Based on miR-150 a new target, KChIP.1 (K (+ channel interacting protein 1, was uncovered, which is specifically upregulated in developing central memory CD8 T cells. Our studies indicate that cell fate determination such as surface phenotype and self-renewal may be decided at the pre-effector stage on the basis of the balancing effects of a discrete number of microRNAs. These results may have implications for the development of T cell vaccines and T cell-based adoptive therapies.

  11. Geoditin A Induces Oxidative Stress and Apoptosis on Human Colon HT29 Cells

    Directory of Open Access Journals (Sweden)

    Wing-Keung Liu

    2010-01-01

    Full Text Available Geoditin A, an isomalabaricane triterpene isolated from the marine sponge Geodia japonica, has been demonstrated to dissipate mitochondrial membrane potential, activate caspase 3, decrease cytoplasmic proliferating cell nuclear antigen (PCNA, and induce apoptosis of leukemia cells, but the underlying mechanism remains unclear [1]. In this study, we found fragmentation of Golgi structure, suppression of transferrin receptor expression, production of oxidants, and DNA fragmentation in human colon cancer HT29 cells after treatment with geoditin A for 24 h. This apoptosis was not abrogated by chelation of intracellular iron with salicylaldehyde isonicotinoyl hydrazone (SIH, but suppressed by N-acetylcysteine (NAC, a thiol antioxidant and GSH precursor, indicating that the cytotoxic effect of geoditin A is likely mediated by a NAC-inhibitable oxidative stress. Our results provide a better understanding of the apoptotic properties and chemotherapeutical potential of this marine triterpene.

  12. Adjuvant chemotherapy versus chemoradiotherapy for small cell lung cancer with lymph node metastasis: a retrospective observational study with use of a national database in Japan

    OpenAIRE

    Urushiyama, Hirokazu; Jo, Taisuke; Yasunaga, Hideo; Yamauchi, Yasuhiro; Matsui, Hiroki; Hasegawa, Wakae; Takeshima, Hideyuki; Hiraishi, Yoshihisa; Mitani, Akihisa; Fushimi, Kiyohide; Nagase, Takahide

    2017-01-01

    Background The optimal postoperative treatment strategy for small cell lung cancer (SCLC) remains unclear, especially in patients with lymph node metastasis. We aimed to compare the outcomes of patients with SCLC and lymph node metastasis treated with postoperative adjuvant chemotherapy or chemoradiotherapy. Methods We retrospectively collected data on patients with postoperative SCLC diagnosed with N1 and N2 lymph node metastasis from the Diagnosis Procedure Combination database in Japan, be...

  13. External light activates hair follicle stem cells through eyes via an ipRGC-SCN-sympathetic neural pathway.

    Science.gov (United States)

    Fan, Sabrina Mai-Yi; Chang, Yi-Ting; Chen, Chih-Lung; Wang, Wei-Hung; Pan, Ming-Kai; Chen, Wen-Pin; Huang, Wen-Yen; Xu, Zijian; Huang, Hai-En; Chen, Ting; Plikus, Maksim V; Chen, Shih-Kuo; Lin, Sung-Jan

    2018-06-29

    Changes in external light patterns can alter cell activities in peripheral tissues through slow entrainment of the central clock in suprachiasmatic nucleus (SCN). It remains unclear whether cells in otherwise photo-insensitive tissues can achieve rapid responses to changes in external light. Here we show that light stimulation of animals' eyes results in rapid activation of hair follicle stem cells with prominent hair regeneration. Mechanistically, light signals are interpreted by M1-type intrinsically photosensitive retinal ganglion cells (ipRGCs), which signal to the SCN via melanopsin. Subsequently, efferent sympathetic nerves are immediately activated. Increased norepinephrine release in skin promotes hedgehog signaling to activate hair follicle stem cells. Thus, external light can directly regulate tissue stem cells via an ipRGC-SCN autonomic nervous system circuit. Since activation of sympathetic nerves is not limited to skin, this circuit can also facilitate rapid adaptive responses to external light in other homeostatic tissues.

  14. Cellular cytotoxic response induced by highly purified multi-wall carbon nanotube in human lung cells.

    Science.gov (United States)

    Tsukahara, Tamotsu; Haniu, Hisao

    2011-06-01

    Carbon nanotubes, a promising nanomaterial with unique characteristics, have applications in a variety of fields. The cytotoxic effects of carbon nanotubes are partially due to the induction of oxidative stress; however, the detailed mechanisms of nanotube cytotoxicity and their interaction with cells remain unclear. In this study, the authors focus on the acute toxicity of vapor-grown carbon fiber, HTT2800, which is one of the most highly purified multi-wall carbon nanotubes (MWCNT) by high-temperature thermal treatment. The authors exposed human bronchial epithelial cells (BEAS-2B) to HTT2800 and measured the cellular uptake, mitochondrial function, cellular LDH release, apoptotic signaling, reactive oxygen species (ROS) generation and pro-inflammatory cytokine release. The HTT2800-exposed cells showed cellular uptake of the carbon nanotube, increased cell death, enhanced DNA damage, and induced cytokine release. However, the exposed cells showed no obvious intracellular ROS generation. These cellular and molecular findings suggest that HTT2800 could cause a potentially adverse inflammatory response in BEAS-2B cells.

  15. Scoulerine affects microtubule structure, inhibits proliferation, arrests cell cycle and thus culminates in the apoptotic death of cancer cells.

    Science.gov (United States)

    Habartova, Klara; Havelek, Radim; Seifrtova, Martina; Kralovec, Karel; Cahlikova, Lucie; Chlebek, Jakub; Cermakova, Eva; Mazankova, Nadezda; Marikova, Jana; Kunes, Jiri; Novakova, Lucie; Rezacova, Martina

    2018-03-19

    Scoulerine is an isoquinoline alkaloid, which indicated promising suppression of cancer cells growth. However, the mode of action (MOA) remained unclear. Cytotoxic and antiproliferative properties were determined in this study. Scoulerine reduces the mitochondrial dehydrogenases activity of the evaluated leukemic cells with IC 50 values ranging from 2.7 to 6.5 µM. The xCELLigence system revealed that scoulerine exerted potent antiproliferative activity in lung, ovarian and breast carcinoma cell lines. Jurkat and MOLT-4 leukemic cells treated with scoulerine were decreased in proliferation and viability. Scoulerine acted to inhibit proliferation through inducing G2 or M-phase cell cycle arrest, which correlates well with the observed breakdown of the microtubule network, increased Chk1 Ser345, Chk2 Thr68 and mitotic H3 Ser10 phosphorylation. Scoulerine was able to activate apoptosis, as determined by p53 upregulation, increase caspase activity, Annexin V and TUNEL labeling. Results highlight the potent antiproliferative and proapoptotic function of scoulerine in cancer cells caused by its ability to interfere with the microtubule elements of the cytoskeleton, checkpoint kinase signaling and p53 proteins. This is the first study of the mechanism of scoulerine at cellular and molecular level. Scoulerine is a potent antimitotic compound and that it merits further investigation as an anticancer drug.

  16. Local Nucleosome Dynamics Facilitate Chromatin Accessibility in Living Mammalian Cells

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    Saera Hihara

    2012-12-01

    Full Text Available Genome information, which is three-dimensionally organized within cells as chromatin, is searched and read by various proteins for diverse cell functions. Although how the protein factors find their targets remains unclear, the dynamic and flexible nature of chromatin is likely crucial. Using a combined approach of fluorescence correlation spectroscopy, single-nucleosome imaging, and Monte Carlo computer simulations, we demonstrate local chromatin dynamics in living mammalian cells. We show that similar to interphase chromatin, dense mitotic chromosomes also have considerable chromatin accessibility. For both interphase and mitotic chromatin, we observed local fluctuation of individual nucleosomes (∼50 nm movement/30 ms, which is caused by confined Brownian motion. Inhibition of these local dynamics by crosslinking impaired accessibility in the dense chromatin regions. Our findings show that local nucleosome dynamics drive chromatin accessibility. We propose that this local nucleosome fluctuation is the basis for scanning genome information.

  17. Function and Biosynthesis of Cell Wall α-1,3-Glucan in Fungi

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    Akira Yoshimi

    2017-11-01

    Full Text Available Although α-1,3-glucan is a major cell wall polysaccharide in filamentous fungi, its biological functions remain unclear, except that it acts as a virulence factor in animal and plant pathogenic fungi: it conceals cell wall β-glucan on the fungal cell surface to circumvent recognition by hosts. However, cell wall α-1,3-glucan is also present in many of non-pathogenic fungi. Recently, the universal function of α-1,3-glucan as an aggregation factor has been demonstrated. Applications of fungi with modified cell wall α-1,3-glucan in the fermentation industry and of in vitro enzymatically-synthesized α-1,3-glucan in bio-plastics have been developed. This review focuses on the recent progress in our understanding of the biological functions and biosynthetic mechanism of cell wall α-1,3-glucan in fungi. We briefly consider the history of studies on α-1,3-glucan, overview its biological functions and biosynthesis, and finally consider the industrial applications of fungi deficient in α-1,3-glucan.

  18. Evaluation of Cytochalasin B-Induced Membrane Vesicles Fusion Specificity with Target Cells

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    Marina Gomzikova

    2018-01-01

    Full Text Available Extracellular vesicles (EV represent a promising vector system for biomolecules and drug delivery due to their natural origin and participation in intercellular communication. As the quantity of EVs is limited, it was proposed to induce the release of membrane vesicles from the surface of human cells by treatment with cytochalasin B. Cytochalasin B-induced membrane vesicles (CIMVs were successfully tested as a vector for delivery of dye, nanoparticles, and a chemotherapeutic. However, it remained unclear whether CIMVs possess fusion specificity with target cells and thus might be used for more targeted delivery of therapeutics. To answer this question, CIMVs were obtained from human prostate cancer PC3 cells. The diameter of obtained CIMVs was 962,13 ± 140,6 nm. We found that there is no statistically significant preference in PC3 CIMVs fusion with target cells of the same type. According to our observations, the greatest impact on CIMVs entry into target cells is by the heterophilic interaction of CIMV membrane receptors with the surface proteins of target cells.

  19. TH17, TH22 and Treg cells are enriched in the healthy human cecum.

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    Martin J Wolff

    Full Text Available There is increasing evidence that dysregulation of CD4(+ T cell populations leads to intestinal inflammation, but the regional distribution of these populations throughout the intestinal tract in healthy individuals remains unclear. Here, we show that T(H17, T(H22 and T(Reg cells are enriched in the healthy human cecum compared to the terminal ileum and sigmoid colon, whereas T(H1 and T(H2 cells do not significantly vary by location. Transcriptional profiling analysis of paired pinch biopsies from different regions of the intestine identified significant differences in the metabolic state of the terminal ileum, cecum, and sigmoid colon. An increased proportion of T(H17 cells was positively associated with expression of resistin (RETN and negatively associated with expression of trefoil factor 1 (TFF1. These results suggest that CD4(+ T helper cells that are important in maintaining mucosal barrier function may be enriched in the cecum as a result of metabolic differences of the surrounding microenvironment.

  20. Sequestration of human cytomegalovirus by human renal and mammary epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Twite, Nicolas [Institute for Medical Immunology, Université Libre de Bruxelles, Rue A. Bolland 8, B-6041 Charleroi (Belgium); Andrei, Graciela [Laboratory of Virology and Chemotherapy, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven (Belgium); Kummert, Caroline [ImmuneHealth, Rue A. Bolland 8, B-6041 Charleroi (Belgium); Donner, Catherine [Department of Obstetrics and Gynecology, Erasme Hospital, Route de Lennik 808, 1070 Brussels (Belgium); Perez-Morga, David [Laboratory of Molecular Parasitology, Institut de Biologie et Médecine Moléculaires, Université Libre de Bruxelles, Gosselies (Belgium); De Vos, Rita [Pathology Department, U.Z. Leuven, Minderbroedersstraat 12, Leuven (Belgium); Snoeck, Robert, E-mail: Robert.Snoeck@Rega.kuleuven.be [Laboratory of Virology and Chemotherapy, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven (Belgium); Marchant, Arnaud, E-mail: arnaud.marchant@ulb.ac.be [Institute for Medical Immunology, Université Libre de Bruxelles, Rue A. Bolland 8, B-6041 Charleroi (Belgium); ImmuneHealth, Rue A. Bolland 8, B-6041 Charleroi (Belgium)

    2014-07-15

    Urine and breast milk represent the main routes of human cytomegalovirus (HCMV) transmission but the contribution of renal and mammary epithelial cells to viral excretion remains unclear. We observed that kidney and mammary epithelial cells were permissive to HCMV infection and expressed immediate early, early and late antigens within 72 h of infection. During the first 24 h after infection, high titers of infectious virus were measured associated to the cells and in culture supernatants, independently of de novo synthesis of virus progeny. This phenomenon was not observed in HCMV-infected fibroblasts and suggested the sequestration and the release of HCMV by epithelial cells. This hypothesis was supported by confocal and electron microscopy analyses. The sequestration and progressive release of HCMV by kidney and mammary epithelial cells may play an important role in the excretion of the virus in urine and breast milk and may thereby contribute to HCMV transmission. - Highlights: • Primary renal and mammary epithelial cells are permissive to HCMV infection. • HCMV is sequestered by epithelial cells and this phenomenon does not require viral replication. • HCMV sequestration by epithelial cells is reduced by antibodies and IFN-γ.

  1. Natural killer cells recognize friend retrovirus-infected erythroid progenitor cells through NKG2D-RAE-1 interactions In Vivo.

    Science.gov (United States)

    Ogawa, Tatsuya; Tsuji-Kawahara, Sachiyo; Yuasa, Takae; Kinoshita, Saori; Chikaishi, Tomomi; Takamura, Shiki; Matsumura, Haruo; Seya, Tsukasa; Saga, Toshihiko; Miyazawa, Masaaki

    2011-06-01

    Natural killer (NK) cells function as early effector cells in the innate immune defense against viral infections and also participate in the regulation of normal and malignant hematopoiesis. NK cell activities have been associated with early clearance of viremia in experimental simian immunodeficiency virus and clinical human immunodeficiency virus type 1 (HIV-1) infections. We have previously shown that NK cells function as major cytotoxic effector cells in vaccine-induced immune protection against Friend virus (FV)-induced leukemia, and NK cell depletion totally abrogates the above protective immunity. However, how NK cells recognize retrovirus-infected cells remains largely unclear. The present study demonstrates a correlation between the expression of the products of retinoic acid early transcript-1 (RAE-1) genes in target cells and their susceptibility to killing by NK cells isolated from FV-infected animals. This killing was abrogated by antibodies blocking the NKG2D receptor in vitro. Further, the expression of RAE-1 proteins on erythroblast surfaces increased early after FV inoculation, and administration of an RAE-1-blocking antibody resulted in increased spleen infectious centers and exaggerated pathology, indicating that FV-infected erythroid cells are recognized by NK cells mainly through the NKG2D-RAE-1 interactions in vivo. Enhanced retroviral replication due to host gene-targeting resulted in markedly increased RAE-1 expression in the absence of massive erythroid cell proliferation, indicating a direct role of retroviral replication in RAE-1 upregulation.

  2. The Phosphodiesterase 4 Inhibitor Roflumilast Protects against Cigarette Smoke Extract-Induced Mitophagy-Dependent Cell Death in Epithelial Cells.

    Science.gov (United States)

    Kyung, Sun Young; Kim, Yu Jin; Son, Eun Suk; Jeong, Sung Hwan; Park, Jeong Woong

    2018-04-01

    Recent studies show that mitophagy, the autophagy-dependent turnover of mitochondria, mediates pulmonary epithelial cell death in response to cigarette smoke extract (CSE) exposure and contributes to the development of emphysema in vivo during chronic cigarette smoke (CS) exposure, although the underlying mechanisms remain unclear. In this study, we investigated the role of mitophagy in the regulation of CSE-exposed lung bronchial epithelial cell (Beas-2B) death. We also investigated the role of a phosphodiesterase 4 inhibitor, roflumilast, in CSE-induced mitophagy-dependent cell death. Our results demonstrated that CSE induces mitophagy in Beas-2B cells through mitochondrial dysfunction and increased the expression levels of the mitophagy regulator protein, PTEN-induced putative kinase-1 (PINK1), and the mitochondrial fission protein, dynamin-1-like protein (DRP1). CSE-induced epithelial cell death was significantly increased in Beas-2B cells exposed to CSE but was decreased by small interfering RNA-dependent knockdown of DRP1. Treatment with roflumilast in Beas-2B cells inhibited CSE-induced mitochondrial dysfunction and mitophagy by inhibiting the expression of phospho-DRP1 and -PINK1. Roflumilast protected against cell death and increased cell viability, as determined by the lactate dehydrogenase release test and the MTT assay, respectively, in Beas-2B cells exposed to CSE. These findings suggest that roflumilast plays a protective role in CS-induced mitophagy-dependent cell death. Copyright©2018. The Korean Academy of Tuberculosis and Respiratory Diseases.

  3. Comparison of mesenchymal stem cells released from poly(N-isopropylacrylamide) copolymer film and by trypsinization

    International Nuclear Information System (INIS)

    Yang Lei; Liu Tianqing; Song Kedong; Jiang Lili; Wu Shuang; Guo Wenhua; Cheng Fang; Lu, Jian R

    2012-01-01

    Temperature-responsive platforms containing poly(N-isopropylacrylamide) (PNIPAAm) have been developed as an effective substitute for enzymatic treatment to recover adherent cells, but it remains unclear whether this alternative harvesting method tends to support stem cells preserving them being primitive. This study mainly investigated the biological properties of mesenchymal stem cells derived from rat bone marrow and human adipose tissue (BM-MSCs and AT-MSCs) after being cultured on PNIPAAm copolymer films and recovered by temperature drop, and compared the cells harvested from glass coverslips with trypsinization as controls. The experimental results demonstrated that after three serial passages, the released MSCs from thermal liftoff showed no significant differences in cell morphology, immunophenotype and osteogenesis for BM-MSCs or adipogenesis for AT-MSCs, but had higher viability, stronger proliferation and higher adipogenic differentiation for BM-MSCs or higher osteogenic differentiation for AT-MSCs compared with the trypsinization group. Besides, more proteins remained around or within the cell membranes upon temperature drop. It is concluded that cell detachment with more extracellular matrix proteins facilitates the maintenance of membrane proteins, and accordingly preserves MSC properties related to viability, proliferation and differentiation to some extent. This indicates that the PNIPAAm copolymer films and their matching cooling treatment can be used as effective alternatives to the existing culture substrates and traditional enzymatic digestion for MSCs. (paper)

  4. Building Synthetic Sterols Computationally - Unlocking the Secrets of Evolution?

    DEFF Research Database (Denmark)

    Róg, Tomasz; Pöyry, Sanja; Vattulainen, Ilpo

    2015-01-01

    Cholesterol is vital in regulating the physical properties of animal cell membranes. While it remains unclear what renders cholesterol so unique, it is known that other sterols are less capable in modulating membrane properties, and there are membrane proteins whose function is dependent on chole......Cholesterol is vital in regulating the physical properties of animal cell membranes. While it remains unclear what renders cholesterol so unique, it is known that other sterols are less capable in modulating membrane properties, and there are membrane proteins whose function is dependent...

  5. Adipose-derived mesenchymal stem cells promote cell proliferation and invasion of epithelial ovarian cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Yijing; Tang, Huijuan; Guo, Yan; Guo, Jing; Huang, Bangxing; Fang, Fang; Cai, Jing, E-mail: caijingmmm@hotmail.com; Wang, Zehua, E-mail: zehuawang@163.net

    2015-09-10

    Adipose-derived mesenchymal stem cell (ADSC) is an important component of tumor microenvironment. However, whether ADSCs have a hand in ovarian cancer progression remains unclear. In this study, we investigated the impact of human ADSCs derived from the omentum of normal donors on human epithelial ovarian cancer (EOC) cells in vitro and in vivo. Direct and indirect co-culture models including ADSCs and human EOC cell lines were established and the effects of ADSCs on EOC cell proliferation were evaluated by EdU incorporation and flow cytometry. Transwell migration assays and detection of MMPs were performed to assess the invasion activity of EOC cells in vitro. Mouse models were established by intraperitoneal injection of EOC cells with or without concomitant ADSCs to investigate the role of ADSCs in tumor progression in vivo. We found that ADSCs significantly promoted proliferation and invasion of EOC cells in both direct and indirect co-culture assays. In addition, after co-culture with ADSCs, EOC cells secreted higher levels of matrix metalloproteinases (MMPs), and inhibition of MMP2 and MMP9 partially relieved the tumor-promoting effects of ADSCs in vitro. In mouse xenograft models, we confirmed that ADSCs promoted EOC growth and metastasis and elevated the expression of MMP2 and MMP9. Our findings indicate that omental ADSCs play a promotive role during ovarian cancer progression. - Highlights: • Omental adipose derived stem cells enhanced growth and invasion properties of ovarian cancer cells. • Adipose derived stem cells promoted the growth and metastasis of ovarian cancer in mice models. • Adipose derived stem cells promoted MMPs expression and secretion of ovarian cancer cells. • Elevated MMPs mediated the tumor promoting effects of ADSCs.

  6. Characterization of aldehyde dehydrogenase 1 high ovarian cancer cells: Towards targeted stem cell therapy.

    Science.gov (United States)

    Sharrow, Allison C; Perkins, Brandy; Collector, Michael I; Yu, Wayne; Simons, Brian W; Jones, Richard J

    2016-08-01

    The cancer stem cell (CSC) paradigm hypothesizes that successful clinical eradication of CSCs may lead to durable remission for patients with ovarian cancer. Despite mounting evidence in support of ovarian CSCs, their phenotype and clinical relevance remain unclear. We and others have found high aldehyde dehydrogenase 1 (ALDH(high)) expression in a variety of normal and malignant stem cells, and sought to better characterize ALDH(high) cells in ovarian cancer. We compared ALDH(high) to ALDH(low) cells in two ovarian cancer models representing distinct subtypes: FNAR-C1 cells, derived from a spontaneous rat endometrioid carcinoma, and the human SKOV3 cell line (described as both serous and clear cell subtypes). We assessed these populations for stem cell features then analyzed expression by microarray and qPCR. ALDH(high) cells displayed CSC properties, including: smaller size, quiescence, regenerating the phenotypic diversity of the cell lines in vitro, lack of contact inhibition, nonadherent growth, multi-drug resistance, and in vivo tumorigenicity. Microarray and qPCR analysis of the expression of markers reported by others to enrich for ovarian CSCs revealed that ALDH(high) cells of both models showed downregulation of CD24, but inconsistent expression of CD44, KIT and CD133. However, the following druggable targets were consistently expressed in the ALDH(high) cells from both models: mTOR signaling, her-2/neu, CD47 and FGF18/FGFR3. Based on functional characterization, ALDH(high) ovarian cancer cells represent an ovarian CSC population. Differential gene expression identified druggable targets that have the potential for therapeutic efficacy against ovarian CSCs from multiple subtypes. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Adipose-derived mesenchymal stem cells promote cell proliferation and invasion of epithelial ovarian cancer

    International Nuclear Information System (INIS)

    Chu, Yijing; Tang, Huijuan; Guo, Yan; Guo, Jing; Huang, Bangxing; Fang, Fang; Cai, Jing; Wang, Zehua

    2015-01-01

    Adipose-derived mesenchymal stem cell (ADSC) is an important component of tumor microenvironment. However, whether ADSCs have a hand in ovarian cancer progression remains unclear. In this study, we investigated the impact of human ADSCs derived from the omentum of normal donors on human epithelial ovarian cancer (EOC) cells in vitro and in vivo. Direct and indirect co-culture models including ADSCs and human EOC cell lines were established and the effects of ADSCs on EOC cell proliferation were evaluated by EdU incorporation and flow cytometry. Transwell migration assays and detection of MMPs were performed to assess the invasion activity of EOC cells in vitro. Mouse models were established by intraperitoneal injection of EOC cells with or without concomitant ADSCs to investigate the role of ADSCs in tumor progression in vivo. We found that ADSCs significantly promoted proliferation and invasion of EOC cells in both direct and indirect co-culture assays. In addition, after co-culture with ADSCs, EOC cells secreted higher levels of matrix metalloproteinases (MMPs), and inhibition of MMP2 and MMP9 partially relieved the tumor-promoting effects of ADSCs in vitro. In mouse xenograft models, we confirmed that ADSCs promoted EOC growth and metastasis and elevated the expression of MMP2 and MMP9. Our findings indicate that omental ADSCs play a promotive role during ovarian cancer progression. - Highlights: • Omental adipose derived stem cells enhanced growth and invasion properties of ovarian cancer cells. • Adipose derived stem cells promoted the growth and metastasis of ovarian cancer in mice models. • Adipose derived stem cells promoted MMPs expression and secretion of ovarian cancer cells. • Elevated MMPs mediated the tumor promoting effects of ADSCs

  8. Electromagnetic fields mediate efficient cell reprogramming into a pluripotent state.

    Science.gov (United States)

    Baek, Soonbong; Quan, Xiaoyuan; Kim, Soochan; Lengner, Christopher; Park, Jung-Keug; Kim, Jongpil

    2014-10-28

    Life on Earth is constantly exposed to natural electromagnetic fields (EMFs), and it is generally accepted that EMFs may exert a variety of effects on biological systems. Particularly, extremely low-frequency electromagnetic fields (EL-EMFs) affect biological processes such as cell development and differentiation; however, the fundamental mechanisms by which EMFs influence these processes remain unclear. Here we show that EMF exposure induces epigenetic changes that promote efficient somatic cell reprogramming to pluripotency. These epigenetic changes resulted from EMF-induced activation of the histone lysine methyltransferase Mll2. Remarkably, an EMF-free system that eliminates Earth's naturally occurring magnetic field abrogates these epigenetic changes, resulting in a failure to undergo reprogramming. Therefore, our results reveal that EMF directly regulates dynamic epigenetic changes through Mll2, providing an efficient tool for epigenetic reprogramming including the acquisition of pluripotency.

  9. Crohn's disease intestinal CD4+ T cells have impaired interleukin-10 productionwhich is not restored by probiotic bacteria

    DEFF Research Database (Denmark)

    Hvas, Christian L; Kelsen, Jens; Agnholt, Jørgen

    2007-01-01

    OBJECTIVE: Crohn's disease (CD) has been associated with low mucosal interleukin (IL)-10 production, but the mechanism behind this deficiency remains unclear. The aim of this study was to investigate IL-10 and interferon (IFN)-gamma production in intestinal CD4+ T cells from CD patients and healthy...... volunteers (HV) and to examine how this was affected by bacterial products and the presence or absence of autologous dendritic cells. MATERIAL AND METHODS: We cultured intestinal CD4+ T cells from CD patients (n=9) and HV (n=6) and differentiated dendritic cells from their peripheral monocytes. Intestinal T...... this imbalance in CD, but tended to do so in HV. When there were no dendritic cells, CD intestinal T cells responded to autologous bacteria with an increased IFN-gamma production (2.3+/-1.3 ng/ml) compared with HV intestinal T cells (0.3+/-0.2 ng/ml). CONCLUSIONS: Crohn's disease intestinal CD4+ T cells display...

  10. Cyclic AMP-Responsive Element-Binding Protein (CREB is Critical in Autoimmunity by Promoting Th17 but Inhibiting Treg Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Xiaohu Wang

    2017-11-01

    Full Text Available The molecular mechanisms that govern differential T cell development into pro-inflammatory Th17 vs. regulatory T (Treg cells remain unclear. Here, we show that selective deletion of CREB in T cells or Th17 cells impaired Th17 cell differentiation in vitro and in vivo, and led to resistance to autoimmune diseases. Mechanistically, CREB, activated by CD3-PKC-ϴ signaling, plays a key role in regulating Th17 cell differentiation, at least in part through directly binding to the Il17-Il17f gene locus. Unexpectedly, although dispensable for FOXP3 expression and for the homeostasis and suppressive function of thymus-derived Treg cells, CREB negatively regulates the survival of TGF-β-induced Treg cells, and deletion of CREB resulted in increased FOXP3+ Treg cells in the intestine and protection in a colitis model. Thus, CREB is critical in autoimmune diseases by promoting Th17 cell and inhibiting de novo Treg cell generation.

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

    Science.gov (United States)

    Watson, Alan M; Klimstra, William B

    2017-04-11

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

  12. The human vascular endothelial cell line HUV-EC-C harbors the integrated HHV-6B genome which remains stable in long term culture.

    Science.gov (United States)

    Shioda, Setsuko; Kasai, Fumio; Ozawa, Midori; Hirayama, Noriko; Satoh, Motonobu; Kameoka, Yousuke; Watanabe, Ken; Shimizu, Norio; Tang, Huamin; Mori, Yasuko; Kohara, Arihiro

    2018-02-01

    Human herpes virus 6 (HHV-6) is a common human pathogen that is most often detected in hematopoietic cells. Although human cells harboring chromosomally integrated HHV-6 can be generated in vitro, the availability of such cell lines originating from in vivo tissues is limited. In this study, chromosomally integrated HHV-6B has been identified in a human vascular endothelial cell line, HUV-EC-C (IFO50271), derived from normal umbilical cord tissue. Sequence analysis revealed that the viral genome was similar to the HHV-6B HST strain. FISH analysis using a HHV-6 DNA probe showed one signal in each cell, detected at the distal end of the long arm of chromosome 9. This was consistent with a digital PCR assay, validating one copy of the viral DNA. Because exposure of HUV-EC-C to chemicals did not cause viral reactivation, long term cell culture of HUV-EC-C was carried out to assess the stability of viral integration. The growth rate was altered depending on passage numbers, and morphology also changed during culture. SNP microarray profiles showed some differences between low and high passages, implying that the HUV-EC-C genome had changed during culture. However, no detectable change was observed in chromosome 9, where HHV-6B integration and the viral copy number remained unchanged. Our results suggest that integrated HHV-6B is stable in HUV-EC-C despite genome instability.

  13. 3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration.

    Science.gov (United States)

    Juang, Jyuhn-Huarng; Kuo, Chien-Hung; Peng, Shih-Jung; Tang, Shiue-Cheng

    2015-02-01

    The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histology with cell tracing to reveal the participation of Schwann cells and pericytes in mouse islet transplantation. Longitudinal studies of the grafts under the kidney capsule identify that the donor Schwann cells and pericytes re-associate with the engrafted islets at the peri-graft and perivascular domains, respectively, indicating their adaptability in transplantation. Based on the morphological proximity and cellular reactivity, we propose that the new islet microenvironment should include the peri-graft Schwann cell sheath and perivascular pericytes as an integral part of the new tissue.

  14. 3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration

    Directory of Open Access Journals (Sweden)

    Jyuhn-Huarng Juang

    2015-02-01

    Full Text Available The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histology with cell tracing to reveal the participation of Schwann cells and pericytes in mouse islet transplantation. Longitudinal studies of the grafts under the kidney capsule identify that the donor Schwann cells and pericytes re-associate with the engrafted islets at the peri-graft and perivascular domains, respectively, indicating their adaptability in transplantation. Based on the morphological proximity and cellular reactivity, we propose that the new islet microenvironment should include the peri-graft Schwann cell sheath and perivascular pericytes as an integral part of the new tissue.

  15. Interaction between adipose tissue-derived mesenchymal stem cells and regulatory T-cells

    OpenAIRE

    Engela, Anja; Baan, Carla; Peeters, Anna; Weimar, Willem; Hoogduijn, Martin

    2013-01-01

    textabstractMesenchymal stem cells (MSCs) exhibit immunosuppressive capabilities, which have evoked interest in their application as cell therapy in transplant patients. So far it has been unclear whether allogeneic MSCs and host regulatory T-cells (Tregs) functionally influence each other. We investigated the interaction between both cell types using perirenal adipose tissue-derived MSCs (ASCs) from kidney donors and Tregs from blood bank donors or kidney recipients 6 months after transplant...

  16. Reprogramming mediated radio-resistance of 3D-grown cancer cells

    International Nuclear Information System (INIS)

    Xue Gang; Ren Zhenxin; Chen Yaxiong; Zhu Jiayun; Du Yarong; Pan Dong; Li Xiaoman; Hu Burong; Grabham, Peter W.

    2015-01-01

    In vitro 3D growth of tumors is a new cell culture model that more closely mimics the features of the in vivo environment and is being used increasingly in the field of biological and medical research. It has been demonstrated that cancer cells cultured in 3D matrices are more radio-resistant compared with cells in monolayers. However, the mechanisms causing this difference remain unclear. Here we show that cancer cells cultured in a 3D microenvironment demonstrated an increase in cells with stem cell properties. This was confirmed by the finding that cells in 3D cultures upregulated the gene and protein expression of the stem cell reprogramming factors such as OCT4, SOX2, NANOG, LIN28 and miR-302a, compared with cells in monolayers. Moreover, the expression of β-catenin, a regulating molecule of reprogramming factors, also increased in 3D-grown cancer cells. These findings suggest that cancer cells were reprogrammed to become stem cell-like cancer cells in a 3D growth culture microenvironment. Since cancer stem cell-like cells demonstrate an increased radio-resistance and chemo-resistance, our results offer a new perspective as to why. Our findings shed new light on understanding the features of the 3D growth cell model and its application in basic research into clinical radiotherapy and medicine. (author)

  17. Specific Intensity Direct Current (DC) Electric Field Improves Neural Stem Cell Migration and Enhances Differentiation towards βIII-Tubulin+ Neurons

    Science.gov (United States)

    Zhao, Huiping; Steiger, Amanda; Nohner, Mitch; Ye, Hui

    2015-01-01

    Control of stem cell migration and differentiation is vital for efficient stem cell therapy. Literature reporting electric field–guided migration and differentiation is emerging. However, it is unknown if a field that causes cell migration is also capable of guiding cell differentiation—and the mechanisms for these processes remain unclear. Here, we report that a 115 V/m direct current (DC) electric field can induce directional migration of neural precursor cells (NPCs). Whole cell patching revealed that the cell membrane depolarized in the electric field, and buffering of extracellular calcium via EGTA prevented cell migration under these conditions. Immunocytochemical staining indicated that the same electric intensity could also be used to enhance differentiation and increase the percentage of cell differentiation into neurons, but not astrocytes and oligodendrocytes. The results indicate that DC electric field of this specific intensity is capable of promoting cell directional migration and orchestrating functional differentiation, suggestively mediated by calcium influx during DC field exposure. PMID:26068466

  18. Gene expression analysis uncovers novel Hedgehog interacting protein (HHIP) effects in human bronchial epithelial cells

    Science.gov (United States)

    Zhou, Xiaobo; Qiu, Weiliang; Sathirapongsasuti, J. Fah.; Cho, Michael H.; Mancini, John D.; Lao, Taotao; Thibault, Derek M.; Litonjua, Gus; Bakke, Per S.; Gulsvik, Amund; Lomas, David A.; Beaty, Terri H.; Hersh, Craig P.; Anderson, Christopher; Geigenmuller, Ute; Raby, Benjamin A.; Rennard, Stephen I.; Perrella, Mark A.; Choi, Augustine M.K.; Quackenbush, John; Silverman, Edwin K.

    2013-01-01

    Hedgehog Interacting Protein (HHIP) was implicated in chronic obstructive pulmonary disease (COPD) by genome-wide association studies (GWAS). However, it remains unclear how HHIP contributes to COPD pathogenesis. To identify genes regulated by HHIP, we performed gene expression microarray analysis in a human bronchial epithelial cell line (Beas-2B) stably infected with HHIP shRNAs. HHIP silencing led to differential expression of 296 genes; enrichment for variants nominally associated with COPD was found. Eighteen of the differentially expressed genes were validated by real-time PCR in Beas-2B cells. Seven of 11 validated genes tested in human COPD and control lung tissues demonstrated significant gene expression differences. Functional annotation indicated enrichment for extracellular matrix and cell growth genes. Network modeling demonstrated that the extracellular matrix and cell proliferation genes influenced by HHIP tended to be interconnected. Thus, we identified potential HHIP targets in human bronchial epithelial cells that may contribute to COPD pathogenesis. PMID:23459001

  19. Role for early-differentiated natural killer cells in infectious mononucleosis.

    Science.gov (United States)

    Azzi, Tarik; Lünemann, Anna; Murer, Anita; Ueda, Seigo; Béziat, Vivien; Malmberg, Karl-Johan; Staubli, Georg; Gysin, Claudine; Berger, Christoph; Münz, Christian; Chijioke, Obinna; Nadal, David

    2014-10-16

    A growing body of evidence suggests that the human natural killer (NK)-cell compartment is phenotypically and functionally heterogeneous and is composed of several differentiation stages. Moreover, NK-cell subsets have been shown to exhibit adaptive immune features during herpes virus infection in experimental mice and to expand preferentially during viral infections in humans. However, both phenotype and role of NK cells during acute symptomatic Epstein-Barr virus (EBV) infection, termed infectious mononucleosis (IM), remain unclear. Here, we longitudinally assessed the kinetics, the differentiation, and the proliferation of subsets of NK cells in pediatric IM patients. Our results indicate that acute IM is characterized by the preferential proliferation of early-differentiated CD56(dim) NKG2A(+) immunoglobulin-like receptor(-) NK cells. Moreover, this NK-cell subset exhibits features of terminal differentiation and persists at higher frequency during at least the first 6 months after acute IM. Finally, we demonstrate that this NK-cell subset preferentially degranulates and proliferates on exposure to EBV-infected B cells expressing lytic antigens. Thus, early-differentiated NK cells might play a key role in the immune control of primary infection with this persistent tumor-associated virus. © 2014 by The American Society of Hematology.

  20. Curcumin prevents human dendritic cell response to immune stimulants

    International Nuclear Information System (INIS)

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

    2008-01-01

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

  1. It takes two to tango, a dance between the cells of origin and cancer stem cells in the Drosophila larval brain.

    Science.gov (United States)

    Janssens, Derek H; Lee, Cheng-Yu

    2014-04-01

    During malignant transformation the cells of origin give rise to cancer stem cells which possess the capacity to undergo limitless rounds of self-renewing division, regenerating themselves while producing more tumor cells. Within normal tissues, a limitless self-renewal capacity is unique to the stem cells, which divide asymmetrically to produce more restricted progenitors. Accumulating evidence suggests that misregulation of the self-renewal machinery in stem cell progeny can lead to tumorigenesis, but how it influences the properties of the resulting tumors remains unclear. Studies of the type II neural stem cell (neuroblast) lineages in the Drosophila larval brain have identified a regulatory cascade that promotes commitment to a progenitor cell identity by restricting their response to the self-renewal machinery. Brain tumor (Brat) and Numb initiate this cascade by asymmetrically extinguishing the activity of the self-renewal factors. Subsequently, Earmuff (Erm) and the SWI/SNF complex stably restrict the competence of the progenitor cell to respond to reactivation of self-renewal mechanisms. Together, this cascade programs the progenitor cell to undergo limited rounds of division, generating exclusive differentiated progeny. Here we review how defects in this cascade lead to tumor initiation and how inhibiting the self-renewal mechanisms may be an effective strategy to block CSC expansion. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. A CREB-MPP7-AMOT Regulatory Axis Controls Muscle Stem Cell Expansion and Self-Renewal Competence

    Directory of Open Access Journals (Sweden)

    Lydia Li

    2017-10-01

    Full Text Available Summary: Skeletal muscle regeneration requires resident muscle stem cells, termed satellite cells (SCs. SCs are largely quiescent during homeostasis yet become activated upon injury to supply myonuclei and self-renewed SCs. Molecular mechanisms underlying the competence of SCs to proliferate and self-renew in response to injury remain unclear. Here, we show that CREB activity establishes proliferative potential during SC quiescence. SCs with inhibited CREB activity remain quiescent and positioned in their niche, but upon injury, they cannot enter or maintain a proliferative state for expansion and self-renewal. We demonstrate mechanistically that Mpp7 is a CREB target and its functional mediator. MPP7 loss affects the level and sub-cellular localization of AMOT and YAP1 in quiescent SCs. Furthermore, MPP7 and AMOT are required for YAP1 nuclear accumulation, and the three are individually required for a proliferative state in myoblasts. We propose that the CREB-MPP7-AMOT-YAP1 axis establishes the competence of quiescent SCs to expand and self-renew, thereby preserving stem cell function. : Satellite cells are quiescent muscle stem cells that have the ability to regenerate muscles after injury. Li and Fan reveal an MPP7-AMOT-YAP1 regulatory axis that acts downstream of CREB to instill satellite cell competence. They also show how this regulatory axis prepares satellite cells for robust muscle regeneration after injury.

  3. p38β, A Novel Regulatory Target of Pokemon in Hepatic Cells

    Directory of Open Access Journals (Sweden)

    Ying Tan

    2013-06-01

    Full Text Available Pokemon is an important proto-oncogene involved in various biological processes and cancer development, such as cell differentiation, tumorigenesis and metastasis. Pokemon is recognized as a transcription factor localized upstream of several oncogenes, regulating their expression. p38MAPKs act as key regulatory factors in cellular signaling pathways associated with inflammatory responses, cell proliferation, differentiation and survival. p38β, a member of p38MAPK family, is closely correlated with tumorigenesis, but the mechanism of activation remains unclear. In this study, we found overexpression of Pokemon promoted the growth, migration and invasion of HepG2 cells. However, a p38 inhibitor SB202190 efficiently attenuated the promoting effect of Pokemon in the HepG2 cells. Targeted expression or silencing of Pokemon changed cellular p38β protein level and phosphorylation of downstream ATF2 in the p38 signaling pathway. Both dual luciferase report assay and ChIP assay suggested that p38β is a novel regulatory target of the transcription factor Pokemon and positively regulated by Pokemon in hepatic cells.

  4. p38β, A novel regulatory target of Pokemon in hepatic cells.

    Science.gov (United States)

    Chen, Zhe; Liu, Feng; Zhang, Nannan; Cao, Deliang; Liu, Min; Tan, Ying; Jiang, Yuyang

    2013-06-27

    Pokemon is an important proto-oncogene involved in various biological processes and cancer development, such as cell differentiation, tumorigenesis and metastasis. Pokemon is recognized as a transcription factor localized upstream of several oncogenes, regulating their expression. p38MAPKs act as key regulatory factors in cellular signaling pathways associated with inflammatory responses, cell proliferation, differentiation and survival. p38β, a member of p38MAPK family, is closely correlated with tumorigenesis, but the mechanism of activation remains unclear. In this study, we found overexpression of Pokemon promoted the growth, migration and invasion of HepG2 cells. However, a p38 inhibitor SB202190 efficiently attenuated the promoting effect of Pokemon in the HepG2 cells. Targeted expression or silencing of Pokemon changed cellular p38β protein level and phosphorylation of downstream ATF2 in the p38 signaling pathway. Both dual luciferase report assay and ChIP assay suggested that p38β is a novel regulatory target of the transcription factor Pokemon and positively regulated by Pokemon in hepatic cells.

  5. Antitumor action of 3-bromopyruvate implicates reorganized tumor growth regulatory components of tumor milieu, cell cycle arrest and induction of mitochondria-dependent tumor cell death.

    Science.gov (United States)

    Yadav, Saveg; Kujur, Praveen Kumar; Pandey, Shrish Kumar; Goel, Yugal; Maurya, Babu Nandan; Verma, Ashish; Kumar, Ajay; Singh, Rana Pratap; Singh, Sukh Mahendra

    2018-01-15

    Evidences demonstrate that metabolic inhibitor 3-bromopyruvate (3-BP) exerts a potent antitumor action against a wide range of malignancies. However, the effect of 3-BP on progression of the tumors of thymic origin remains unexplored. Although, constituents of tumor microenvironment (TME) plays a pivotal role in regulation of tumor progression, it remains unclear if 3-BP can alter the composition of the crucial tumor growth regulatory components of the external surrounding of tumor cells. Thus, the present investigation attempts to understand the effect of 3-BP administration to a host bearing a progressively growing tumor of thymic origin on tumor growth regulatory soluble, cellular and biophysical components of tumor milieu vis-à-vis understanding its association with tumor progression, accompanying cell cycle events and mode of cell death. Further, the expression of cell survival regulatory molecules and hemodynamic characteristics of the tumor milieu were analysed to decipher mechanisms underlying the antitumor action of 3-BP. Administration of 3-BP to tumor-bearing hosts retarded tumor progression accompanied by induction of tumor cell death, cell cycle arrest, declined metabolism, inhibited mitochondrial membrane potential, elevated release of cytochrome c and altered hemodynamics. Moreover, 3-BP reconstituted the external milieu, in concurrence with deregulated glucose and pH homeostasis and increased tumor infiltration by NK cells, macrophages, and T lymphocytes. Further, 3-BP administration altered the expression of key regulatory molecules involved in glucose uptake, intracellular pH and tumor cell survival. The outcomes of this study will help in optimizing the therapeutic application of 3-BP by targeting crucial tumor growth regulatory components of tumor milieu. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. RodZ links MreB to cell wall synthesis to mediate MreB rotation and robust morphogenesis.

    Science.gov (United States)

    Morgenstein, Randy M; Bratton, Benjamin P; Nguyen, Jeffrey P; Ouzounov, Nikolay; Shaevitz, Joshua W; Gitai, Zemer

    2015-10-06

    The rod shape of most bacteria requires the actin homolog, MreB. Whereas MreB was initially thought to statically define rod shape, recent studies found that MreB dynamically rotates around the cell circumference dependent on cell wall synthesis. However, the mechanism by which cytoplasmic MreB is linked to extracytoplasmic cell wall synthesis and the function of this linkage for morphogenesis has remained unclear. Here we demonstrate that the transmembrane protein RodZ mediates MreB rotation by directly or indirectly coupling MreB to cell wall synthesis enzymes. Furthermore, we map the RodZ domains that link MreB to cell wall synthesis and identify mreB mutants that suppress the shape defect of ΔrodZ without restoring rotation, uncoupling rotation from rod-like growth. Surprisingly, MreB rotation is dispensable for rod-like shape determination under standard laboratory conditions but is required for the robustness of rod shape and growth under conditions of cell wall stress.

  7. Single-cell RNA-Seq reveals cell heterogeneity and hierarchy within mouse mammary epithelia.

    Science.gov (United States)

    Sun, Heng; Miao, Zhengqiang; Zhang, Xin; Chan, Un In; Su, Sek Man; Guo, Sen; Wong, Chris Koon Ho; Xu, Xiaoling; Deng, Chu-Xia

    2018-04-17

    The mammary gland is very intricately and well organized into distinct tissues, including epithelia, endothelia, adipocytes, and stromal and immune cells. Many mammary gland diseases, such as breast cancer arise from abnormalities in the mammary epithelium, which is mainly composed of two distinct lineages, the basal and luminal cells. Because of the limitation of traditional transcriptome analysis of bulk mammary cells, the hierarchy and heterogeneity of mammary cells within these two lineages remain unclear. To this end, using single-cell RNA-Seq coupled with FACS analysis and principal component analysis, we determined gene expression profiles of mammary epithelial cells of virgin and pregnant mice. These analyses revealed a much higher heterogeneity among the mammary cells than has been previously reported and enabled cell classification into distinct subgroups according to signature gene markers present in each group. We also identified and verified a rare CDH5+ cell subpopulation within a basal cell lineage as quiescent mammary stem cells (MaSCs). Moreover, using pseudo-temporal analysis, we reconstructed the developmental trajectory of mammary epithelia and uncovered distinct changes in gene expression and in biological functions of mammary cells along the developmental process. In conclusion, our work greatly refines the resolution of the cellular hierarchy in developing mammary tissues. The discovery of CDH5+ cells as MaSCs in these tissues may have implications for our understanding of the initiation, development, and pathogenesis of mammary tumors. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Crystal structure of Vδ1 T cell receptor in complex with CD1d-sulfatide shows MHC-like recognition of a self-lipid by human γδ T cells.

    Science.gov (United States)

    Luoma, Adrienne M; Castro, Caitlin D; Mayassi, Toufic; Bembinster, Leslie A; Bai, Li; Picard, Damien; Anderson, Brian; Scharf, Louise; Kung, Jennifer E; Sibener, Leah V; Savage, Paul B; Jabri, Bana; Bendelac, Albert; Adams, Erin J

    2013-12-12

    The nature of the antigens recognized by γδ T cells and their potential recognition of major histocompatibility complex (MHC)-like molecules has remained unclear. Members of the CD1 family of lipid-presenting molecules are suggested ligands for Vδ1 TCR-expressing γδ T cells, the major γδ lymphocyte population in epithelial tissues. We crystallized a Vδ1 TCR in complex with CD1d and the self-lipid sulfatide, revealing the unusual recognition of CD1d by germline Vδ1 residues spanning all complementarity-determining region (CDR) loops, as well as sulfatide recognition separately encoded by nongermline CDR3δ residues. Binding and functional analysis showed that CD1d presenting self-lipids, including sulfatide, was widely recognized by gut Vδ1+ γδ T cells. These findings provide structural demonstration of MHC-like recognition of a self-lipid by γδ T cells and reveal the prevalence of lipid recognition by innate-like T cell populations. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Human Natural Killer Cells Prevent Infectious Mononucleosis Features by Targeting Lytic Epstein-Barr Virus Infection

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    Obinna Chijioke

    2013-12-01

    Full Text Available Primary infection with the human oncogenic Epstein-Barr virus (EBV can result in infectious mononucleosis (IM, a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies.

  10. Exogenous stem cells pioneer a biobridge to the advantage of host brain cells following stroke: New insights for clinical applications

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    Marci G Crowley

    2017-01-01

    Full Text Available Stroke continues to maintain its status as one of the top causes of mortality within the United States. Currently, the only Food and Drug Administration (FDA-approved drug in place for stroke patients, tissue plasminogen activator (tPA, has a rigid therapeutic window, closing at approximately 4.5 h after stroke onset. Due to this short time frame and other restrictions, such as any condition that increases a patient's risk for hemorrhaging, it has been predicted that <5% of ischemic stroke patients benefit from tPA. Given that rehabilitation therapy remains the only other option for stroke victims, there is a clear unmet clinical need for treatment available for the remaining 95%. While still considered an experimental treatment, the utilization of stem cell therapies for stroke holds consistent promise. Copious preclinical studies report the capacity for transplanted stem cells to rescue the brain parenchyma surrounding the stroke-induced infarct core. At present, the exact mechanisms in which stem cells contribute a robust therapeutic benefit remains unclear. Following stem cell administration, researchers have observed cell replacement, an increase in growth factors, and a reduction in inflammation. With a deeper understanding of the precise mechanism of stem cells, these therapies can be optimized in the clinic to afford the greatest therapeutic benefit. Recent studies have depicted a unique method of endogenous stem cell activation as a result of stem cell therapy. In both traumatic brain injury and stroke models, transplanted mesenchymal stromal cells (MSCs facilitated a pathway between the neurogenic niches of the brain and the damaged area through extracellular matrix remodeling. The biobridge pioneered by the MSCs was utilized by the endogenous stem cells, and these cells were able to travel to the damaged areas distal to the neurogenic niches, a feat unachievable without prior remodeling. These studies broaden our understanding of stem

  11. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells.

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    Wang, Ruoxing; Guo, Yan-Lin

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Linking incomplete reprogramming to the improved pluripotency of murine embryonal carcinoma cell-derived pluripotent stem cells.

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    Gang Chang

    Full Text Available Somatic cell nuclear transfer (SCNT has been proved capable of reprogramming various differentiated somatic cells into pluripotent stem cells. Recently, induced pluripotent stem cells (iPS have been successfully derived from mouse and human somatic cells by the over-expression of a combination of transcription factors. However, the molecular mechanisms underlying the reprogramming mediated by either the SCNT or iPS approach are poorly understood. Increasing evidence indicates that many tumor pathways play roles in the derivation of iPS cells. Embryonal carcinoma (EC cells have the characteristics of both stem cells and cancer cells and thus they might be the better candidates for elucidating the details of the reprogramming process. Although previous studies indicate that EC cells cannot be reprogrammed into real pluripotent stem cells, the reasons for this remain unclear. Here, nuclei from mouse EC cells (P19 were transplanted into enucleated oocytes and pluripotent stem cells (P19 NTES cells were subsequently established. Interestingly, P19 NTES cells prolonged the development of tetraploid aggregated embryos compared to EC cells alone. More importantly, we found that the expression recovery of the imprinted H19 gene was dependent on the methylation state in the differential methylation region (DMR. The induction of Nanog expression, however, was independent of the promoter region DNA methylation state in P19 NTES cells. A whole-genome transcriptome analysis further demonstrated that P19 NTES cells were indeed the intermediates between P19 cells and ES cells and many interesting genes were uncovered that may be responsible for the failed reprogramming of P19 cells. To our knowledge, for the first time, we linked incomplete reprogramming to the improved pluripotency of EC cell-derived pluripotent stem cells. The candidate genes we discovered may be useful not only for understanding the mechanisms of reprogramming, but also for deciphering the

  13. Heat-modified citrus pectin induces apoptosis-like cell death and autophagy in HepG2 and A549 cancer cells.

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    Leclere, Lionel; Fransolet, Maude; Cote, Francois; Cambier, Pierre; Arnould, Thierry; Van Cutsem, Pierre; Michiels, Carine

    2015-01-01

    Cancer is still one of the leading causes of death worldwide, and finding new treatments remains a major challenge. Previous studies showed that modified forms of pectin, a complex polysaccharide present in the primary plant cell wall, possess anticancer properties. Nevertheless, the mechanism of action of modified pectin and the pathways involved are unclear. Here, we show that citrus pectin modified by heat treatment induced cell death in HepG2 and A549 cells. The induced cell death differs from classical apoptosis because no DNA cleavage was observed. In addition, Z-VAD-fmk, a pan-caspase inhibitor, did not influence the observed cell death in HepG2 cells but appeared to be partly protective in A549 cells, indicating that heat-modified citrus pectin might induce caspase-independent cell death. An increase in the abundance of the phosphatidylethanolamine-conjugated Light Chain 3 (LC3) protein and a decrease in p62 protein abundance were observed in both cell types when incubated in the presence of heat-modified citrus pectin. These results indicate the activation of autophagy. To our knowledge, this is the first time that autophagy has been revealed in cells incubated in the presence of a modified form of pectin. This autophagy activation appears to be protective, at least for A549 cells, because its inhibition with 3-methyladenine increased the observed modified pectin-induced cytotoxicity. This study confirms the potential of modified pectin to improve chemotherapeutic cancer treatments.

  14. Heat-modified citrus pectin induces apoptosis-like cell death and autophagy in HepG2 and A549 cancer cells.

    Directory of Open Access Journals (Sweden)

    Lionel Leclere

    Full Text Available Cancer is still one of the leading causes of death worldwide, and finding new treatments remains a major challenge. Previous studies showed that modified forms of pectin, a complex polysaccharide present in the primary plant cell wall, possess anticancer properties. Nevertheless, the mechanism of action of modified pectin and the pathways involved are unclear. Here, we show that citrus pectin modified by heat treatment induced cell death in HepG2 and A549 cells. The induced cell death differs from classical apoptosis because no DNA cleavage was observed. In addition, Z-VAD-fmk, a pan-caspase inhibitor, did not influence the observed cell death in HepG2 cells but appeared to be partly protective in A549 cells, indicating that heat-modified citrus pectin might induce caspase-independent cell death. An increase in the abundance of the phosphatidylethanolamine-conjugated Light Chain 3 (LC3 protein and a decrease in p62 protein abundance were observed in both cell types when incubated in the presence of heat-modified citrus pectin. These results indicate the activation of autophagy. To our knowledge, this is the first time that autophagy has been revealed in cells incubated in the presence of a modified form of pectin. This autophagy activation appears to be protective, at least for A549 cells, because its inhibition with 3-methyladenine increased the observed modified pectin-induced cytotoxicity. This study confirms the potential of modified pectin to improve chemotherapeutic cancer treatments.

  15. The actin cytoskeleton modulates the activation of iNKT cells by segregating CD1d nanoclusters on antigen-presenting cells

    Science.gov (United States)

    Torreno-Pina, Juan A.; Manzo, Carlo; Salio, Mariolina; Aichinger, Michael C.; Oddone, Anna; Lakadamyali, Melike; Shepherd, Dawn; Besra, Gurdyal S.; Cerundolo, Vincenzo

    2016-01-01

    Invariant natural killer T (iNKT) cells recognize endogenous and exogenous lipid antigens presented in the context of CD1d molecules. The ability of iNKT cells to recognize endogenous antigens represents a distinct immune recognition strategy, which underscores the constitutive memory phenotype of iNKT cells and their activation during inflammatory conditions. However, the mechanisms regulating such “tonic” activation of iNKT cells remain unclear. Here, we show that the spatiotemporal distribution of CD1d molecules on the surface of antigen-presenting cells (APCs) modulates activation of iNKT cells. By using superresolution microscopy, we show that CD1d molecules form nanoclusters at the cell surface of APCs, and their size and density are constrained by the actin cytoskeleton. Dual-color single-particle tracking revealed that diffusing CD1d nanoclusters are actively arrested by the actin cytoskeleton, preventing their further coalescence. Formation of larger nanoclusters occurs in the absence of interactions between CD1d cytosolic tail and the actin cytoskeleton and correlates with enhanced iNKT cell activation. Importantly and consistently with iNKT cell activation during inflammatory conditions, exposure of APCs to the Toll-like receptor 7/8 agonist R848 increases nanocluster density and iNKT cell activation. Overall, these results define a previously unidentified mechanism that modulates iNKT cell autoreactivity based on the tight control by the APC cytoskeleton of the sizes and densities of endogenous antigen-loaded CD1d nanoclusters. PMID:26798067

  16. A DNA Vaccine Protects Human Immune Cells against Zika Virus Infection in Humanized Mice

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    Guohua Yi

    2017-11-01

    Full Text Available A DNA vaccine encoding prM and E protein has been shown to induce protection against Zika virus (ZIKV infection in mice and monkeys. However, its effectiveness in humans remains undefined. Moreover, identification of which immune cell types are specifically infected in humans is unclear. We show that human myeloid cells and B cells are primary targets of ZIKV in humanized mice. We also show that a DNA vaccine encoding full length prM and E protein protects humanized mice from ZIKV infection. Following administration of the DNA vaccine, humanized DRAG mice developed antibodies targeting ZIKV as measured by ELISA and neutralization assays. Moreover, following ZIKV challenge, vaccinated animals presented virtually no detectable virus in human cells and in serum, whereas unvaccinated animals displayed robust infection, as measured by qRT-PCR. Our results utilizing humanized mice show potential efficacy for a targeted DNA vaccine against ZIKV in humans.

  17. Microparticle Shedding from Neural Progenitor Cells and Vascular Compartment Cells Is Increased in Ischemic Stroke.

    Science.gov (United States)

    Chiva-Blanch, Gemma; Suades, Rosa; Crespo, Javier; Peña, Esther; Padró, Teresa; Jiménez-Xarrié, Elena; Martí-Fàbregas, Joan; Badimon, Lina

    2016-01-01

    Ischemic stroke has shown to induce platelet and endothelial microparticle shedding, but whether stroke induces microparticle shedding from additional blood and vascular compartment cells is unclear. Neural precursor cells have been shown to replace dying neurons at sites of brain injury; however, if neural precursor cell activation is associated to microparticle shedding, and whether this activation is maintained at long term and associates to stroke type and severity remains unknown. We analyzed neural precursor cells and blood and vascular compartment cells microparticle shedding after an acute ischemic stroke. Forty-four patients were included in the study within the first 48h after the onset of stroke. The cerebral lesion size was evaluated at 3-7 days of the stroke. Circulating microparticles from neural precursor cells and blood and vascular compartment cells (platelets, endothelial cells, erythrocytes, leukocytes, lymphocytes, monocytes and smooth muscle cells) were analyzed by flow cytometry at the onset of stroke and at 7 and 90 days. Forty-four age-matched high cardiovascular risk subjects without documented vascular disease were used as controls. Compared to high cardiovascular risk controls, patients showed higher number of neural precursor cell- and all blood and vascular compartment cell-derived microparticles at the onset of stroke, and after 7 and 90 days. At 90 days, neural precursor cell-derived microparticles decreased and smooth muscle cell-derived microparticles increased compared to levels at the onset of stroke, but only in those patients with the highest stroke-induced cerebral lesions. Stroke increases blood and vascular compartment cell and neural precursor cell microparticle shedding, an effect that is chronically maintained up to 90 days after the ischemic event. These results show that stroke induces a generalized blood and vascular cell activation and the initiation of neuronal cell repair process after stroke. Larger cerebral lesions

  18. Microparticle Shedding from Neural Progenitor Cells and Vascular Compartment Cells Is Increased in Ischemic Stroke.

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    Gemma Chiva-Blanch

    Full Text Available Ischemic stroke has shown to induce platelet and endothelial microparticle shedding, but whether stroke induces microparticle shedding from additional blood and vascular compartment cells is unclear. Neural precursor cells have been shown to replace dying neurons at sites of brain injury; however, if neural precursor cell activation is associated to microparticle shedding, and whether this activation is maintained at long term and associates to stroke type and severity remains unknown. We analyzed neural precursor cells and blood and vascular compartment cells microparticle shedding after an acute ischemic stroke.Forty-four patients were included in the study within the first 48h after the onset of stroke. The cerebral lesion size was evaluated at 3-7 days of the stroke. Circulating microparticles from neural precursor cells and blood and vascular compartment cells (platelets, endothelial cells, erythrocytes, leukocytes, lymphocytes, monocytes and smooth muscle cells were analyzed by flow cytometry at the onset of stroke and at 7 and 90 days. Forty-four age-matched high cardiovascular risk subjects without documented vascular disease were used as controls.Compared to high cardiovascular risk controls, patients showed higher number of neural precursor cell- and all blood and vascular compartment cell-derived microparticles at the onset of stroke, and after 7 and 90 days. At 90 days, neural precursor cell-derived microparticles decreased and smooth muscle cell-derived microparticles increased compared to levels at the onset of stroke, but only in those patients with the highest stroke-induced cerebral lesions.Stroke increases blood and vascular compartment cell and neural precursor cell microparticle shedding, an effect that is chronically maintained up to 90 days after the ischemic event. These results show that stroke induces a generalized blood and vascular cell activation and the initiation of neuronal cell repair process after stroke. Larger

  19. Inhibition of Curcumin on ZAKα Activity Resultant in Apoptosis and Anchorage-Independent Growth in Cancer Cells.

    Science.gov (United States)

    Lee, Jin-Sun; Wang, Tsu-Shing; Lin, Ming Cheng; Lin, Wei-Wen; Yang, Jaw-Ji

    2017-10-31

    Curcumin, a popular yellow pigment of the dietary spice turmeric, has been reported to inhibit cell growth and to induce apoptosis in a wide variety of cancer cells. Although numerous studies have investigated anticancer effects of curcumin, the precise molecular mechanism of action remains unidentified. Whereas curcumin mediates cell survival and apoptosis through mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling cascades, its impact on the upstream regulation of MAPK is unclear. The leucine-zipper and sterile-α motif kinase alpha (ZAKα), a mitogen-activated protein kinase kinase kinase (MAP3K), activates the c-Jun N-terminal kinase (JNK) and NF-κB pathway. This paper investigated the prospective involvement of ZAKα in curcumin-induced effects on cancer cells. Our results suggest that the antitumor activity of curcumin is mediated via a mechanism involving inhibition of ZAKα activity.

  20. microRNA-365, down-regulated in colon cancer, inhibits cell cycle progression and promotes apoptosis of colon cancer cells by probably targeting Cyclin D1 and Bcl-2.

    Science.gov (United States)

    Nie, Jing; Liu, Lin; Zheng, Wei; Chen, Lin; Wu, Xin; Xu, Yingxin; Du, Xiaohui; Han, Weidong

    2012-01-01

    Deregulated microRNAs participate in carcinogenesis and cancer progression, but their roles in cancer development remain unclear. In this study, miR-365 expression was found to be downregulated in human colon cancer tissues as compared with that in matched non-neoplastic mucosa tissues, and its downregulation was correlated with cancer progression and poor survival in colon cancer patients. Functional studies revealed that restoration of miR-365 expression inhibited cell cycle progression, promoted 5-fluorouracil-induced apoptosis and repressed tumorigenicity in colon cancer cell lines. Furthermore, bioinformatic prediction and experimental validation were used to identify miR-365 target genes and indicated that the antitumor effects of miR-365 were probably mediated by its targeting and repression of Cyclin D1 and Bcl-2 expression, thus inhibiting cell cycle progression and promoting apoptosis. These results suggest that downregulation of miR-365 in colon cancer may have potential applications in prognosis prediction and gene therapy in colon cancer patients.

  1. Neutralisation of HIV-1 cell-cell spread by human and llama antibodies.

    Science.gov (United States)

    McCoy, Laura E; Groppelli, Elisabetta; Blanchetot, Christophe; de Haard, Hans; Verrips, Theo; Rutten, Lucy; Weiss, Robin A; Jolly, Clare

    2014-10-02

    Direct cell-cell spread of HIV-1 is a very efficient mode of viral dissemination, with increasing evidence suggesting that it may pose a considerable challenge to controlling viral replication in vivo. Much current vaccine research involves the study of broadly neutralising antibodies (bNabs) that arise during natural infection with the aims of eliciting such antibodies by vaccination or incorporating them into novel therapeutics. However, whether cell-cell spread of HIV-1 can be effectively targeted by bNabs remains unclear, and there is much interest in identifying antibodies capable of efficiently neutralising virus transmitted by cell-cell contact. In this study we have tested a panel of bNAbs for inhibition of cell-cell spread, including some not previously evaluated for inhibition of this mode of HIV-1 transmission. We found that three CD4 binding site antibodies, one from an immunised llama (J3) and two isolated from HIV-1-positive patients (VRC01 and HJ16) neutralised cell-cell spread between T cells, while antibodies specific for glycan moieties (2G12, PG9, PG16) and the MPER (2F5) displayed variable efficacy. Notably, while J3 displayed a high level of potency during cell-cell spread we found that the small size of the llama heavy chain-only variable region (VHH) J3 is not required for efficient neutralisation since recombinant J3 containing a full-length human heavy chain Fc domain was significantly more potent. J3 and J3-Fc also neutralised cell-cell spread of HIV-1 from primary macrophages to CD4+ T cells. In conclusion, while bNabs display variable efficacy at preventing cell-cell spread of HIV-1, we find that some CD4 binding site antibodies can inhibit this mode of HIV-1 dissemination and identify the recently described llama antibody J3 as a particularly potent inhibitor. Effective neutralisation of cell-cell spread between physiologically relevant cell types by J3 and J3-Fc supports the development of VHH J3 nanobodies for therapeutic or

  2. Engineering of Systematic Elimination of a Targeted Chromosome in Human Cells

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    Hiroshi Sato

    2017-01-01

    Full Text Available Embryonic trisomy leads to abortion or congenital genetic disorders in humans. The most common autosomal chromosome abnormalities are trisomy of chromosomes 13, 18, and 21. Although alteration of gene dosage is thought to contribute to disorders caused by extra copies of chromosomes, genes associated with specific disease phenotypes remain unclear. To generate a normal cell from a trisomic cell as a means of etiological analysis or candidate therapy for trisomy syndromes, we developed a system to eliminate a targeted chromosome from human cells. Chromosome 21 was targeted by integration of a DNA cassette in HeLa cells that harbored three copies of chromosome 21. The DNA cassette included two inverted loxP sites and a herpes simplex virus thymidine kinase (HSV-tk gene. This system causes missegregation of chromosome 21 after expression of Cre recombinase and subsequently enables the selection of cells lacking the chromosome by culturing in a medium that includes ganciclovir (GCV. Cells harboring only two copies of chromosome 21 were efficiently induced by transfection of a Cre expression vector, indicating that this approach is useful for eliminating a targeted chromosome.

  3. MiRNAs and piRNAs from bone marrow mesenchymal stem cell extracellular vesicles induce cell survival and inhibit cell differentiation of cord blood hematopoietic stem cells: a new insight in transplantation.

    Science.gov (United States)

    De Luca, Luciana; Trino, Stefania; Laurenzana, Ilaria; Simeon, Vittorio; Calice, Giovanni; Raimondo, Stefania; Podestà, Marina; Santodirocco, Michele; Di Mauro, Lazzaro; La Rocca, Francesco; Caivano, Antonella; Morano, Annalisa; Frassoni, Francesco; Cilloni, Daniela; Del Vecchio, Luigi; Musto, Pellegrino

    2016-02-09

    Hematopoietic stem cells (HSC), including umbilical cord blood CD34+ stem cells (UCB-CD34+), are used for the treatment of several diseases. Although different studies suggest that bone marrow mesenchymal stem cells (BM-MSC) support hematopoiesis, the exact mechanism remains unclear. Recently, extracellular vesicles (EVs) have been described as a novel avenue of cell communication, which may mediate BM-MSC effect on HSC. In this work, we studied the interaction between UCB-CD34+ cells and BM-MSC derived EVs. First, by sequencing EV derived miRNAs and piRNAs we found that EVs contain RNAs able to influence UCB-CD34+ cell fate. Accordingly, a gene expression profile of UCB-CD34+ cells treated with EVs, identified about 100 down-regulated genes among those targeted by EV-derived miRNAs and piRNAs (e.g. miR-27b/MPL, miR-21/ANXA1, miR-181/EGR2), indicating that EV content was able to modify gene expression profile of receiving cells. Moreover, we demonstrated that UCB-CD34+ cells, exposed to EVs, significantly changed different biological functions, becoming more viable and less differentiated. UCB-CD34+ gene expression profile also identified 103 up-regulated genes, most of them codifying for chemokines, cytokines and their receptors, involved in chemotaxis of different BM cells, an essential function of hematopoietic reconstitution. Finally, the exposure of UCB-CD34+ cells to EVs caused an increased expression CXCR4, paralleled by an in vivo augmented migration from peripheral blood to BM niche in NSG mice. This study demonstrates the existence of a powerful cross talk between BM-MSC and UCB-CD34+ cells, mediated by EVs, providing new insight in the biology of cord blood transplantation.

  4. Apoptosis and tumor cell death in response to HAMLET (human alpha-lactalbumin made lethal to tumor cells).

    Science.gov (United States)

    Hallgren, Oskar; Aits, Sonja; Brest, Patrick; Gustafsson, Lotta; Mossberg, Ann-Kristin; Wullt, Björn; Svanborg, Catharina

    2008-01-01

    HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a molecular complex derived from human milk that kills tumor cells by a process resembling programmed cell death. The complex consists of partially unfolded alpha-lactalbumin and oleic acid, and both the protein and the fatty acid are required for cell death. HAMLET has broad antitumor activity in vitro, and its therapeutic effect has been confirmed in vivo in a human glioblastoma rat xenograft model, in patients with skin papillomas and in patients with bladder cancer. The mechanisms of tumor cell death remain unclear, however. Immediately after the encounter with tumor cells, HAMLET invades the cells and causes mitochondrial membrane depolarization, cytochrome c release, phosphatidyl serine exposure, and a low caspase response. A fraction of the cells undergoes morphological changes characteristic of apoptosis, but caspase inhibition does not rescue the cells and Bcl-2 overexpression or altered p53 status does not influence the sensitivity of tumor cells to HAMLET. HAMLET also creates a state of unfolded protein overload and activates 20S proteasomes, which contributes to cell death. In parallel, HAMLET translocates to tumor cell nuclei, where high-affinity interactions with histones cause chromatin disruption, loss of transcription, and nuclear condensation. The dying cells also show morphological changes compatible with macroautophagy, and recent studies indicate that macroautophagy is involved in the cell death response to HAMLET. The results suggest that HAMLET, like a hydra with many heads, may interact with several crucial cellular organelles, thereby activating several forms of cell death, in parallel. This complexity might underlie the rapid death response of tumor cells and the broad antitumor activity of HAMLET.

  5. Differential inhibitory and activating NK cell receptor levels and NK/NKT-like cell functionality in chronic and recovered stages of chikungunya.

    Science.gov (United States)

    Thanapati, Subrat; Ganu, Mohini A; Tripathy, Anuradha S

    2017-01-01

    The role of natural killer (NK; CD3-CD56+)/NKT (CD3+CD56+)-like cells in chikungunya virus (CHIKV) disease progression/recovery remains unclear. Here, we investigated the expression profiles and function of NK and NKT-like cells from 35 chronic chikungunya patients, 30 recovered individuals, and 69 controls. Percentage of NKT-like cells was low in chronic chikungunya patients. NKp30+, CD244+, DNAM-1+, and NKG2D+ NK cell percentages were also lower (MFI and/or percentage), while those of CD94+ and NKG2A+ NKT-like cells were higher (MFI and/or percentage) in chronic patients than in recovered subjects. IFN-γ and TNF-α expression on NKT-like cells was high in the chronic patients, while only IFN-γ expression on NK cells was high in the recovered individuals. Furthermore, percentage of perforin+NK cells was low in the chronic patients. Lower cytotoxic activity was observed in the chronic patients than in the controls. CD107a expression on NK and NKT-like cells post anti-CD94/anti-NKG2A blocking was comparable among the patients and controls. Upregulated inhibitory and downregulated activating NK receptor expressions on NK/NKT-like cells, lower perforin+ and CD107a+NK cells are likely responsible for inhibiting the NK and NKT-like cell function in the chronic stage of chikungunya. Therefore, deregulation of NKR expression might underlie CHIKV-induced chronicity.

  6. Reduced generation of lung tissue–resident memory T cells during infancy

    Science.gov (United States)

    Zens, Kyra D.; Chen, Jun Kui; Wu, Felix L.; Cvetkovski, Filip

    2017-01-01

    Infants suffer disproportionately from respiratory infections and generate reduced vaccine responses compared with adults, although the underlying mechanisms remain unclear. In adult mice, lung-localized, tissue-resident memory T cells (TRMs) mediate optimal protection to respiratory pathogens, and we hypothesized that reduced protection in infancy could be due to impaired establishment of lung TRM. Using an infant mouse model, we demonstrate generation of lung-homing, virus-specific T effectors after influenza infection or live-attenuated vaccination, similar to adults. However, infection during infancy generated markedly fewer lung TRMs, and heterosubtypic protection was reduced compared with adults. Impaired TRM establishment was infant–T cell intrinsic, and infant effectors displayed distinct transcriptional profiles enriched for T-bet–regulated genes. Notably, mouse and human infant T cells exhibited increased T-bet expression after activation, and reduction of T-bet levels in infant mice enhanced lung TRM establishment. Our findings reveal that infant T cells are intrinsically programmed for short-term responses, and targeting key regulators could promote long-term, tissue-targeted protection at this critical life stage. PMID:28855242

  7. Reduced generation of lung tissue-resident memory T cells during infancy.

    Science.gov (United States)

    Zens, Kyra D; Chen, Jun Kui; Guyer, Rebecca S; Wu, Felix L; Cvetkovski, Filip; Miron, Michelle; Farber, Donna L

    2017-10-02

    Infants suffer disproportionately from respiratory infections and generate reduced vaccine responses compared with adults, although the underlying mechanisms remain unclear. In adult mice, lung-localized, tissue-resident memory T cells (TRMs) mediate optimal protection to respiratory pathogens, and we hypothesized that reduced protection in infancy could be due to impaired establishment of lung TRM. Using an infant mouse model, we demonstrate generation of lung-homing, virus-specific T effectors after influenza infection or live-attenuated vaccination, similar to adults. However, infection during infancy generated markedly fewer lung TRMs, and heterosubtypic protection was reduced compared with adults. Impaired TRM establishment was infant-T cell intrinsic, and infant effectors displayed distinct transcriptional profiles enriched for T-bet-regulated genes. Notably, mouse and human infant T cells exhibited increased T-bet expression after activation, and reduction of T-bet levels in infant mice enhanced lung TRM establishment. Our findings reveal that infant T cells are intrinsically programmed for short-term responses, and targeting key regulators could promote long-term, tissue-targeted protection at this critical life stage. © 2017 Zens et al.

  8. A novel role of KIF3b in the seminoma cell cycle

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    Shen, Hao-Qing; Xiao, Yu-Xi; She, Zhen-Yu [The Sperm Laboratory, College of Life Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058 (China); Tan, Fu-Qing [The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003 (China); Yang, Wan-Xi, E-mail: wxyang@spermlab.org [The Sperm Laboratory, College of Life Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou 310058 (China)

    2017-03-01

    KIF3b is a protein of the kinesin-2 family which plays an important role in intraflagellar transport. Testis cancer is a common cancer among young men. Its diagnostic rate is increasing and over half of the cases are seminomas. Many aspects of the mechanism and gene expression background of this cancer remain unclear. Using western-blotting and semi-quantitative PCR we found high protein levels of KIF3b enrichment in seminoma tissue despite the mRNA levels remaining equivalent to that of normal testicular tissues. The distribution of KIF3b was mainly in cells with division potential. Wound-healing assays and cell counting kit assays showed that the knockdown of KIF3b significantly suppressed cell migration ability, viability and number in HeLa cells. Immunofluorescence images during the cell cycle revealed that KIF3b tended to gather at the spindles and was enriched at the central spindle. This indicated that KIF3b may also have direct impacts upon spindle formation and cytokinesis. By counting the numbers of nuclei, spindles and cells, we found that the rates of multipolar division and multi-nucleation were raised in KIF3b-knockdown cells. In this way we demonstrate that KIF3b functions importantly in mitosis and may be essential to seminoma cell division and proliferation as well as being necessary for normal cell division. - Highlights: • A significant upregulation of KIF3b is detected in seminoma. • Knockdown of KIF3b impacts on cell proliferation and migration. • KIF3b may have direct impacts upon spindle formation and cytokinesis.

  9. Pulmonary infections in swine induce altered porcine surfactant protein D expression and localization to dendritic cells in bronchial-associated lymphoid tissue

    DEFF Research Database (Denmark)

    Sørensen, C.M.; Holmskov, U.; Aalbæk, B.

    2005-01-01

    , the absence of macrophage marker immunoreactivity and the presence of dendritic cell marker immunoreactivity. Increased expression of pSP-D in the surfactant coincided with presence of pSP-D-positive dendritic cells in bronchus-associated lymphoid tissue (BALT), indicating a possible transport of p...... and with dendritic cells in microbial-induced BALT. The function of the interaction between pSP-D and dendritic cells in BALT remain unclear, but pSP-D could represent a link between the innate and adaptive immune system, facilitating the bacterial antigen presentation by dendritic cells in BALT.......Surfactant protein D (SP-D) is a pattern-recognition molecule of the innate immune system that recognizes various microbial surface-specific carbohydrate and lipid patterns. In vitro data has suggested that this binding may lead to increased microbial association with macrophages and dendritic...

  10. Interaction and modulation of two antagonistic cell wall enzymes of mycobacteria.

    Directory of Open Access Journals (Sweden)

    Erik C Hett

    2010-07-01

    Full Text Available Bacterial cell growth and division require coordinated cell wall hydrolysis and synthesis, allowing for the removal and expansion of cell wall material. Without proper coordination, unchecked hydrolysis can result in cell lysis. How these opposing activities are simultaneously regulated is poorly understood. In Mycobacterium tuberculosis, the resuscitation-promoting factor B (RpfB, a lytic transglycosylase, interacts and synergizes with Rpf-interacting protein A (RipA, an endopeptidase, to hydrolyze peptidoglycan. However, it remains unclear what governs this synergy and how it is coordinated with cell wall synthesis. Here we identify the bifunctional peptidoglycan-synthesizing enzyme, penicillin binding protein 1 (PBP1, as a RipA-interacting protein. PBP1, like RipA, localizes both at the poles and septa of dividing cells. Depletion of the ponA1 gene, encoding PBP1 in M. smegmatis, results in a severe growth defect and abnormally shaped cells, indicating that PBP1 is necessary for viability and cell wall stability. Finally, PBP1 inhibits the synergistic hydrolysis of peptidoglycan by the RipA-RpfB complex in vitro. These data reveal a post-translational mechanism for regulating cell wall hydrolysis and synthesis through protein-protein interactions between enzymes with antagonistic functions.

  11. Exercise and physical training improve physical function in older adults with visual impairments but their effect on falls is unclear: a systematic review

    Directory of Open Access Journals (Sweden)

    Michael Gleeson

    2014-09-01

    [Gleeson M, Sherrington C, Keay L (2014 Exercise and physical training improve physical function in older adults with visual impairments but their effect on falls is unclear: a systematic review. Journal of Physiotherapy 60: 130–135

  12. H19 lncRNA mediates 17β-estradiol-induced cell proliferation in MCF-7 breast cancer cells.

    Science.gov (United States)

    Sun, Hong; Wang, Guo; Peng, Yan; Zeng, Ying; Zhu, Qiong-Ni; Li, Tai-Lin; Cai, Jia-Qin; Zhou, Hong-Hao; Zhu, Yuan-Shan

    2015-06-01

    Estrogen plays a critical role in breast cancer development and progression. However, the mechanism involved in the promotion of breast cancer development and progression by estrogen remains unclear although it has been intensively studied. In the present study, we investigated the estrogen inducibility and functional significance of H19 lncRNA in breast cancer cells and tumor tissues. The screening of 83 disease-related long non-coding RNAs (lncRNAs) revealed that H19 lncRNA was much higher in estrogen receptor (ER)-positive MCF-7 breast cancer cells than in ER-negative MDA-MB-231 cells. 17β-estradiol produced a dose- and time-dependent induction of H19 expression in MCF-7 cells, which was mediated via ERα as evident by the blockade of this 17β-estradiol effect with ICI 182780, a specific ER antagonist and knockdown of ERα using specific RNAi. Moreover, knockdown of H19 lncRNA decreased cell survival and blocked estrogen-induced cell growth while overexpression of H19 lncRNA stimulated cell proliferation. Quantitation of H19 lncRNA in human breast cancer tissues showed that the level of H19 lncRNA was >10-fold higher in ER-positive than in ER-negative tumor tissues. These results suggest that H19 is an estrogen-inducible gene and plays a key role in cell survival and in estrogen-induced cell proliferation in MCF-7 cells, indicating that H19 lncRNA may serve as a biomarker for breast cancer diagnosis and progression, and as a valuable target for breast cancer therapy.

  13. MACC1 facilitates chemoresistance and cancer stem cell-like properties of colon cancer cells through the PI3K/AKT signaling pathway

    Science.gov (United States)

    Wang, Jiankai; Wang, Wenjuan; Cai, Hongyi; Du, Binbin; Zhang, Lijuan; Ma, Wen; Hu, Yongguo; Feng, Shifang; Miao, Guoying

    2017-01-01

    With regards to colon cancer, resistance to 5-fluorouracil (5-FU)-based chemotherapy and cancer stem cells (CSCs) are considered important factors underlying therapy failure. Metastasis-associated colon cancer 1 (MACC1) has been associated with poor prognosis and the promotion of metastasis within several types of cancer. However, the biological behavior of MACC1 in chemoresistance and CSC-like properties remains unclear. In the present study, various methods including gene knockdown, gene overexpression, western blotting, quantitative polymerase chain reaction and MTT assay, have been adopted. According to the results of the present study, MACC1 was depleted in two colon cancer cell lines resistant to 5-FU; subsequently, CSC-like properties and 5-FU sensitivity were investigated. Within 5-FU-resistant cells, cell death was facilitated by MACC1 knockdown. Furthermore, sphere formation and the expression levels of pluripotent markers, including cluster of differentiation (CD) 44, CD133 and Nanog were reduced due to MACC1 depletion. Additionally, it was indicated that the phosphoinositide 3-kinase/protein kinase B signaling pathway may be associated with 5-FU resistance and CSC-like properties via MACC1. PMID:28990068

  14. Heparanase promotes myeloma progression by inducing mesenchymal features and motility of myeloma cells.

    Science.gov (United States)

    Li, Juan; Pan, Qianying; Rowan, Patrick D; Trotter, Timothy N; Peker, Deniz; Regal, Kellie M; Javed, Amjad; Suva, Larry J; Yang, Yang

    2016-03-08

    Bone dissemination and bone disease occur in approximately 80% of patients with multiple myeloma (MM) and are a major cause of patient mortality. We previously demonstrated that MM cell-derived heparanase (HPSE) is a major driver of MM dissemination to and progression in new bone sites. However the mechanism(s) by which HPSE promotes MM progression remains unclear. In the present study, we investigated the involvement of mesenchymal features in HPSE-promoted MM progression in bone. Using a combination of molecular, biochemical, cellular, and in vivo approaches, we demonstrated that (1) HPSE enhanced the expression of mesenchymal markers in both MM and vascular endothelial cells; (2) HPSE expression in patient myeloma cells positively correlated with the expression of the mesenchymal markers vimentin and fibronectin. Additional mechanistic studies revealed that the enhanced mesenchymal-like phenotype induced by HPSE in MM cells is due, at least in part, to the stimulation of the ERK signaling pathway. Finally, knockdown of vimentin in HPSE expressing MM cells resulted in significantly attenuated MM cell dissemination and tumor growth in vivo. Collectively, these data demonstrate that the mesenchymal features induced by HPSE in MM cells contribute to enhanced tumor cell motility and bone-dissemination.

  15. Early loss of Crebbp confers malignant stem cell properties on lymphoid progenitors.

    Science.gov (United States)

    Horton, Sarah J; Giotopoulos, George; Yun, Haiyang; Vohra, Shabana; Sheppard, Olivia; Bashford-Rogers, Rachael; Rashid, Mamunur; Clipson, Alexandra; Chan, Wai-In; Sasca, Daniel; Yiangou, Loukia; Osaki, Hikari; Basheer, Faisal; Gallipoli, Paolo; Burrows, Natalie; Erdem, Ayşegül; Sybirna, Anastasiya; Foerster, Sarah; Zhao, Wanfeng; Sustic, Tonci; Petrunkina Harrison, Anna; Laurenti, Elisa; Okosun, Jessica; Hodson, Daniel; Wright, Penny; Smith, Ken G; Maxwell, Patrick; Fitzgibbon, Jude; Du, Ming Q; Adams, David J; Huntly, Brian J P

    2017-09-01

    Loss-of-function mutations of cyclic-AMP response element binding protein, binding protein (CREBBP) are prevalent in lymphoid malignancies. However, the tumour suppressor functions of CREBBP remain unclear. We demonstrate that loss of Crebbp in murine haematopoietic stem and progenitor cells (HSPCs) leads to increased development of B-cell lymphomas. This is preceded by accumulation of hyperproliferative lymphoid progenitors with a defective DNA damage response (DDR) due to a failure to acetylate p53. We identify a premalignant lymphoma stem cell population with decreased H3K27ac, which undergoes transcriptional and genetic evolution due to the altered DDR, resulting in lymphomagenesis. Importantly, when Crebbp is lost later in lymphopoiesis, cellular abnormalities are lost and tumour generation is attenuated. We also document that CREBBP mutations may occur in HSPCs from patients with CREBBP-mutated lymphoma. These data suggest that earlier loss of Crebbp is advantageous for lymphoid transformation and inform the cellular origins and subsequent evolution of lymphoid malignancies.

  16. BLM has early and late functions in homologous recombination repair in mouse embryonic stem cells

    DEFF Research Database (Denmark)

    Chu, W K; Hanada, K; Kanaar, R

    2010-01-01

    function of BLM remains unclear. Multiple roles have been proposed for BLM in the homologous recombination (HR) repair pathway, including 'early' functions, such as the stimulation of resection of DNA double-strand break ends or displacement of the invading strand of DNA displacement loops, and 'late......' roles, such as dissolution of double Holliday junctions. However, most of the evidence for these putative roles comes from in vitro biochemical data. In this study, we report the characterization of mouse embryonic stem cells with disruption of Blm and/or Rad54 genes. We show that Blm has roles both...

  17. CD34+ mesenchymal cells are a major component of the intestinal stem cells niche at homeostasis and after injury.

    Science.gov (United States)

    Stzepourginski, Igor; Nigro, Giulia; Jacob, Jean-Marie; Dulauroy, Sophie; Sansonetti, Philippe J; Eberl, Gérard; Peduto, Lucie

    2017-01-24

    The intestinal epithelium is continuously renewed by intestinal epithelial stem cells (IESCs) positioned at the base of each crypt. Mesenchymal-derived factors are essential to maintain IESCs; however, the cellular composition and development of such mesenchymal niche remains unclear. Here, we identify pericryptal CD34 + Gp38 + αSMA - mesenchymal cells closely associated with Lgr5 + IESCs. We demonstrate that CD34 + Gp38 + cells are the major intestinal producers of the niche factors Wnt2b, Gremlin1, and R-spondin1, and are sufficient to promote maintenance of Lgr5 + IESCs in intestinal organoids, an effect mainly mediated by Gremlin1. CD34 + Gp38 + cells develop after birth in the intestinal submucosa and expand around the crypts during the third week of life in mice, independently of the microbiota. We further show that pericryptal CD34 + gp38 + cells are rapidly activated by intestinal injury, up-regulating niche factors Gremlin1 and R-spondin1 as well as chemokines, proinflammatory cytokines, and growth factors with key roles in gut immunity and tissue repair, including IL-7, Ccl2, Ptgs2, and Amphiregulin. Our results indicate that CD34 + Gp38 + mesenchymal cells are programmed to develop in the intestine after birth to constitute a specialized microenvironment that maintains IESCs at homeostasis and contribute to intestinal inflammation and repair after injury.

  18. Long Noncoding RNA HOTAIR Controls Cell Cycle by Functioning as a Competing Endogenous RNA in Esophageal Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Kewei Ren

    2016-12-01

    Full Text Available Recent studies have shown that long noncoding RNAs (lncRNAs play pivotal roles in the initiation and progression of cancer, including esophageal squamous cell carcinoma (ESCC. The lncRNA HOX transcript antisense RNA (HOTAIR was reported to be dysregulated and correlated with the progression of ESCC. However, the biological role and the underlying mechanism of HOTAIR in the development of ESCC remain unclear. Herein, we found that HOTAIR was aberrantly upregulated in ESCC cells and that HOTAIR depletion inhibited proliferation and led to G1 cell cycle arrest in ESCC cells. Besides, we found that HOTAIR acted as an endogenous sponge to downregulate miR-1 expression by directly binding to miR-1. Furthermore, HOTAIR overturned the effect of miR-1 on the proliferation and cell cycle profile in ESCC cells, which involved the derepression of cyclin D1 (CCND1 expression, a target of miR-1. Taken together, our study elucidated a novel HOTAIR /miR-1/CCND1 regulatory axis in which HOTAIR acted as a competing endogenous RNA by sponging miR-1 and upregulated CCND1 expression, thereby facilitating the tumorigenesis of ESCC. Investigation of this lncRNA/miRNA/mRNA pathway may contribute to a better understanding of ESCC pathogenesis and facilitate the development of lncRNA-directed therapy against this disease.

  19. Batf3-dependent CD8α+ Dendritic Cells Aggravates Atherosclerosis via Th1 Cell Induction and Enhanced CCL5 Expression in Plaque Macrophages.

    Science.gov (United States)

    Li, Yalin; Liu, Xueyan; Duan, Wei; Tian, Hua; Zhu, Guangming; He, Hao; Yao, Shutong; Yi, Shuying; Song, Wengang; Tang, Hua

    2017-04-01

    Dendritic cells (DCs) play an important role in controlling T cell-mediated adaptive immunity in atherogenesis. However, the role of the basic leucine zipper transcription factor, ATF-like 3 (Batf3)-dependent CD8α + DC subset in atherogenesis remains unclear. Here we show that Batf3 -/- Apoe -/- mice, lacking CD8α + DCs, exhibited a significant reduction in atherogenesis and T help 1 (Th1) cells compared with Apoe -/- controls. Then, we found that CD8α + DCs preferentially induce Th1 cells via secreting interleukin-12 (IL-12), and that the expression of interferon-gamma (IFN-γ)or chemokine (C-C motif) ligand 5 (CCL5) in aorta were significantly decreased in Batf3 -/- Apoe -/- mice. We further demonstrated that macrophages were the major CCL5-expressing cells in the plaque, which was significantly reduced in Batf3 -/- Apoe -/- mice. Furthermore, we found CCL5 expression in macrophages was promoted by IFN-γ. Finally, we showed that Batf3 -/- Apoe -/- mice displayed decreased infiltration of leukocytes in the plaque. Thus, CD8α + DCs aggravated atherosclerosis, likely by inducing Th1 cell response, which promoted CCL5 expression in macrophages and increased infiltration of leukocytes and lesion inflammation. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  20. In Vitro and in Vivo Anticancer Activity of Pardaxin against Proliferation and Growth of Oral Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Yifan Han

    2015-12-01

    Full Text Available Pardaxin (H-GFFALIPKIISSPLFKTLLSAVGSALSSSGGQE-OH, a 33-amino-acid polypeptide, is an antimicrobial peptide (AMP isolated from the marine fish species Pardachirus marmoratus. Pardaxin shows antibacterial and antitumor activities. However, pardaxin-induced inhibition of oral cancer and the mechanism of tumor reduction in buccal pouch carcinogenesis after pardaxin painting remain undetermined. Additionally, the toxic effects of pardaxin on normal tissue remain unclear. The present study investigated the anticancer activity of pardaxin in oral squamous cell carcinoma (OSCC cells in the hamster buccal pouch model with or without 7,12-dimethylbenz[a]anthracene (DMBA pretreatment. This is the first study to confirm the effects of pardaxin on normal tissue and its nontoxic effects in vivo. Cell viability assays and colony formation tests in OSCC cell lines (SCC-4 demonstrated that pardaxin reduced cell viability in a dose-dependent manner. Immunofluorescence staining of cleaved caspase-3 in SCC-4 cells revealed that expression of activated caspase-3 in SCC-4 cells significantly increased after 24-h treatment with pardaxin. Additionally, a cell cycle analysis indicated that pardaxin treatment resulted in the cell cycle arrest of SCC-4 cells in the G2/M phase, thereby limiting cell proliferation. Furthermore, pardaxin treatment substantially alleviated carcinogenesis in the DMBA-induced hamster buccal pouch model by lowering prostaglandin E2 levels. These results suggest that pardaxin is a potential marine drug for adjuvant chemotherapy for human OSCC and oral cancer.

  1. Canine distemper virus utilizes different receptors to infect chicken embryo fibroblasts and vero cells.

    Science.gov (United States)

    Chen, Jun; Liang, Xiu; Chen, Pei-fu

    2011-04-01

    Inducing animal viruses to adapt to chicken embryos or chicken embryo fibroblasts (CEF) is a common method to develop attenuated live vaccines with full security. Canine distemper virus (CDV) also does this, but the mechanisms and particular receptors remain unclear. Virus overlay protein blot assays were carried out on CEF membrane proteins, which were extracted respectively with a Mem-PER™ kit, a radioimmunoprecipitation assay buffer or a modified co-immunoprecipitation method, and revealed a common 57 kDa positive band that differed from the 42-kDa positive band in Vero cells and also from those receptors reported in lymphocytes and 293 cells, indicating a receptor diversity of CDV and the possibility of the 57-kDa protein acting as a receptor that is involved in adaptive infection of CDV Kunming strain to CEF.

  2. Glyceraldehyde-3-phosphate dehydrogenase aggregation inhibitor peptide: A potential therapeutic strategy against oxidative stress-induced cell death.

    Science.gov (United States)

    Itakura, Masanori; Nakajima, Hidemitsu; Semi, Yuko; Higashida, Shusaku; Azuma, Yasu-Taka; Takeuchi, Tadayoshi

    2015-11-13

    The glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has multiple functions, including mediating oxidative stress-induced neuronal cell death. This process is associated with disulfide-bonded GAPDH aggregation. Some reports suggest a link between GAPDH and the pathogenesis of several oxidative stress-related diseases. However, the pathological significance of GAPDH aggregation in disease pathogenesis remains unclear due to the lack of an effective GAPDH aggregation inhibitor. In this study, we identified a GAPDH aggregation inhibitor (GAI) peptide and evaluated its biological profile. The decapeptide GAI specifically inhibited GAPDH aggregation in a concentration-dependent manner. Additionally, the GAI peptide did not affect GAPDH glycolytic activity or cell viability. The GAI peptide also exerted a protective effect against oxidative stress-induced cell death in SH-SY5Y cells. This peptide could potentially serve as a tool to investigate GAPDH aggregation-related neurodegenerative and neuropsychiatric disorders and as a possible therapy for diseases associated with oxidative stress-induced cell death. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. BTG2 Is Down-Regulated and Inhibits Cancer Stem Cell-Like Features of Side Population Cells in Hepatocellular Carcinoma.

    Science.gov (United States)

    Huang, Chen-Song; Zhai, Jing-Ming; Zhu, Xiao-Xu; Cai, Jian-Peng; Chen, Wei; Li, Jian-Hui; Yin, Xiao-Yu

    2017-12-01

    Our previous study found that B cell translocation gene 2 (BTG2) was hyper-methylated and down-regulated in side population (SP) cells of hepatocellular carcinoma (HCC) cell line. However, its clinical significances and biological impacts on HCC SP cells remained unclear. To investigate the prognostic value of BTG2 gene in HCC and its influences on cancer stem cells (CSCs)-like traits of HCC cell line SP cells. BTG2 expression in human HCC and adjacent non-cancerous tissues was detected by immunohistochemical staining and quantitative real-time PCR, and also obtained from GEO and TCGA data. Its prognostic values were assessed. Its biological influences on HCC cell line SP cells were evaluated using cell viability, cell cycle, plate clone-forming assay, and chemoresistance in vitro and tumorigenicity in vivo. BTG2 expression was significantly suppressed in human HCC compared to adjacent non-cancerous tissues. BTG2 expression was correlated with TNM stage, tumor size and vascular invasion. Lower expression of BTG2 was associated with poorer overall survival and disease-free survival. In vitro, overexpression of BTG2 substantially suppressed cell proliferation and accumulation of HCC cell line SP cells in G0/G1 phase. Colony formation ability was markedly suppressed by BTG2 overexpression. Moreover, sensitivity of HCC cell line SP cells to 5-fluorouracil was substantially increased by overexpression of BTG2. Furthermore, tumorigenicity of HCC cell line SP cells transfected with BTG2 plasmids was significantly reduced in vivo. BTG2 gene could regulate the CSC-like traits of HCC cell line SP cells, and it represented as a molecular prognostic marker for HCC.

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

    Science.gov (United States)

    Watson, Alan M.; Klimstra, William B.

    2017-01-01

    The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus. PMID:28398253

  5. Update on Merkel Cell Carcinoma: Epidemiology, Etiopathogenesis, Clinical Features, Diagnosis, and Staging.

    Science.gov (United States)

    Llombart, B; Requena, C; Cruz, J

    2017-03-01

    Merkel cell carcinoma (MCC) is a rare, highly aggressive tumor, and local or regional disease recurrence is common, as is metastasis. MCC usually develops in sun-exposed skin in patients of advanced age. Its incidence has risen 4-fold in recent decades as the population has aged and immunohistochemical techniques have led to more diagnoses. The pathogenesis of MCC remains unclear but UV radiation, immunosuppression, and the presence of Merkel cell polyomavirus in the tumor genome seem to play key roles. This review seeks to update our understanding of the epidemiology, etiology, pathogenesis, and clinical features of MCC. We also review histologic and immunohistochemical features required for diagnosis. MCC staging is discussed, given its great importance in establishing a prognosis for these patients. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  6. Cytoprotective effect of imatinib mesylate in non-BCR-ABL-expressing cells along with autophagosome formation

    International Nuclear Information System (INIS)

    Ohtomo, Tadashi; Miyazawa, Keisuke; Naito, Munekazu; Moriya, Shota; Kuroda, Masahiko; Itoh, Masahiro; Tomoda, Akio

    2010-01-01

    Treatment with imatinib mesylate (IM) results in an increased viable cell number of non-BCR-ABL-expressing cell lines by inhibiting spontaneous apoptosis. Electron microscopy revealed an increase of autophagosomes in response to IM. IM attenuated the cytotoxic effect of cytosine arabinoside, as well as inhibiting cell death with serum-deprived culture. Cytoprotection with autophagosome formation by IM was observed in various leukemia and cancer cell lines as well as normal murine embryonic fibroblasts (MEFs). Complete inhibition of autophagy by knockdown of atg5 in the Tet-off atg5 -/- MEF system attenuated the cytoprotective effect of IM, indicating that the effect is partially dependent on autophagy. However, cytoprotection by IM was not mediated through suppression of ROS production via mitophagy, ER stress via ribophagy, or proapoptotic function of ABL kinase. Although the target tyrosine kinase(s) of IM remains unclear, our data provide novel therapeutic possibilities of using IM for cytoprotection.

  7. Subcellular distribution and mitogenic effect of basic fibroblast growth factor in mesenchymal uncommitted stem cells.

    Science.gov (United States)

    Benavente, Claudia A; Sierralta, Walter D; Conget, Paulette A; Minguell, José J

    2003-06-01

    Uncommitted mesenchymal stem cells (MSC), upon commitment and differentiation give rise to several mature mesenchymal lineages. Although the involvement of specific growth factors, including FGF2, in the development of committed MSC is known, the effect of FGF2 on uncommitted progenitors remains unclear. We have analyzed on a comparative basis, the subcellular distribution and mitogenic effect of FGF2 in committed and uncommitted MSC prepared from human bone marrow. Indirect immunofluorescence studies showed strong nuclear FGF2 staining in both progenitors; however, cytoplasmic staining was only detected in committed cells. Western blot analysis revealed the presence of 22.5 and 21-22 kDa forms of FGF2 in the nucleus of both progenitors; however, their relative content was higher in uncommitted than in committed cells. Exogenous FGF2 stimulated proliferation and sustained quiescence in committed and uncommitted cells, respectively. These results show that both type of progenitors, apart from morphological and proliferative differences, display specific patterns of response to FGF2.

  8. Loss of Optineurin In Vivo Results in Elevated Cell Death and Alters Axonal Trafficking Dynamics

    Science.gov (United States)

    Paulus, Jeremiah D.; Link, Brian A.

    2014-01-01

    Mutations in Optineurin have been associated with ALS, glaucoma, and Paget’s disease of bone in humans, but little is known about how these mutations contribute to disease. Most of the cellular consequences of Optineurin loss have come from in vitro studies, and it remains unclear whether these same defects would be seen in vivo. To answer this question, we assessed the cellular consequences of Optineurin loss in zebrafish embryos to determine if they showed the same defects as have been described in the in vitro studies. We found that loss of Optineurin resulted in increased cell death, as well as subtle cell morphology, cell migration and vesicle trafficking defects. However, unlike experiments on cells in culture, we found no indication that the Golgi apparatus was disrupted or that NF-κB target genes were upregulated. Therefore, we conclude that in vivo loss of Optineurin shows some, but not all, of the defects seen in in vitro work. PMID:25329564

  9. CMV driven CD8(+) T-cell activation is associated with acute rejection in lung transplantation.

    Science.gov (United States)

    Roux, Antoine; Mourin, Gisèle; Fastenackels, Solène; Almeida, Jorge R; Iglesias, Maria Candela; Boyd, Anders; Gostick, Emma; Larsen, Martin; Price, David A; Sacre, Karim; Douek, Daniel C; Autran, Brigitte; Picard, Clément; Miranda, Sandra de; Sauce, Delphine; Stern, Marc; Appay, Victor

    2013-07-01

    Lung transplantation is the definitive treatment for terminal respiratory disease, but the associated mortality rate is high. Acute rejection of the transplanted lung is a key determinant of adverse prognosis. Furthermore, an epidemiological relationship has been established between the occurrence of acute lung rejection and cytomegalovirus infection. However, the reasons for this association remain unclear. Here, we performed a longitudinal characterization of CMV-specific T-cell responses and immune activation status in the peripheral blood and bronchoalveolar lavage fluid of forty-four lung transplant patients. Acute rejection was associated with high levels of cellular activation in the periphery, reflecting strong CMV-specific CD8(+) T-cell activity post-transplant. Peripheral and lung CMV-specific CD8(+) T-cell responses were very similar, and related to the presence of CMV in the transplanted organ. These findings support that activated CMV-specific CD8(+) T-cells in the lung may play a role in promoting acute rejection. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Nano-scaled particles of titanium dioxide convert benign mouse fibrosarcoma cells into aggressive tumor cells.

    Science.gov (United States)

    Onuma, Kunishige; Sato, Yu; Ogawara, Satomi; Shirasawa, Nobuyuki; Kobayashi, Masanobu; Yoshitake, Jun; Yoshimura, Tetsuhiko; Iigo, Masaaki; Fujii, Junichi; Okada, Futoshi

    2009-11-01

    Nanoparticles are prevalent in both commercial and medicinal products; however, the contribution of nanomaterials to carcinogenesis remains unclear. We therefore examined the effects of nano-sized titanium dioxide (TiO(2)) on poorly tumorigenic and nonmetastatic QR-32 fibrosarcoma cells. We found that mice that were cotransplanted subcutaneously with QR-32 cells and nano-sized TiO(2), either uncoated (TiO(2)-1, hydrophilic) or coated with stearic acid (TiO(2)-2, hydrophobic), did not form tumors. However, QR-32 cells became tumorigenic after injection into sites previously implanted with TiO(2)-1, but not TiO(2)-2, and these developing tumors acquired metastatic phenotypes. No differences were observed either histologically or in inflammatory cytokine mRNA expression between TiO(2)-1 and TiO(2)-2 treatments. However, TiO(2)-2, but not TiO(2)-1, generated high levels of reactive oxygen species (ROS) in cell-free conditions. Although both TiO(2)-1 and TiO(2)-2 resulted in intracellular ROS formation, TiO(2)-2 elicited a stronger response, resulting in cytotoxicity to the QR-32 cells. Moreover, TiO(2)-2, but not TiO(2)-1, led to the development of nuclear interstices and multinucleate cells. Cells that survived the TiO(2) toxicity acquired a tumorigenic phenotype. TiO(2)-induced ROS formation and its related cell injury were inhibited by the addition of antioxidant N-acetyl-l-cysteine. These results indicate that nano-sized TiO(2) has the potential to convert benign tumor cells into malignant ones through the generation of ROS in the target cells.

  11. Specific oncogenic activity of the Src-family tyrosine kinase c-Yes in colon carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Florence Sancier

    Full Text Available c-Yes, a member of the Src tyrosine kinase family, is found highly activated in colon carcinoma but its importance relative to c-Src has remained unclear. Here we show that, in HT29 colon carcinoma cells, silencing of c-Yes, but not of c-Src, selectively leads to an increase of cell clustering associated with a localisation of β-catenin at cell membranes and a reduction of expression of β-catenin target genes. c-Yes silencing induced an increase in apoptosis, inhibition of growth in soft-agar and in mouse xenografts, inhibition of cell migration and loss of the capacity to generate liver metastases in mice. Re-introduction of c-Yes, but not c -Src, restores transforming properties of c-Yes depleted cells. Moreover, we found that c-Yes kinase activity is required for its role in β-catenin localisation and growth in soft agar, whereas kinase activity is dispensable for its role in cell migration. We conclude that c-Yes regulates specific oncogenic signalling pathways important for colon cancer progression that is not shared with c-Src.

  12. Characterization of plasma-induced cell membrane permeabilization: focus on OH radical distribution

    International Nuclear Information System (INIS)

    Sasaki, Shota; Honda, Ryosuke; Hokari, Yutaro; Takashima, Keisuke; Kaneko, Toshiro; Kanzaki, Makoto

    2016-01-01

    Non-equilibrium atmospheric-pressure plasma (APP) is used medically for plasma-induced cell permeabilization. However, how plasma irradiation specifically triggers permeabilization remains unclear. In an attempt to identify the dominant factor( s ), the distribution of plasma-produced reactive species was investigated, primarily focusing on OH radicals. A stronger plasma discharge, which produced more OH radicals in the gas phase, also produced more OH radicals in the liquid phase (OH aq ), enhancing the cell membrane permeability. In addition, plasma irradiation-induced enhancement of cell membrane permeability decreased markedly with increased solution thickness (<1 mm), and the plasma-produced OH aq decayed in solution (diffusion length on the order of several hundred micrometers). Furthermore, the horizontally center-localized distribution of OH aq corresponded with the distribution of the permeabilized cells by plasma irradiation, while the overall plasma-produced oxidizing species in solution (detected by iodine-starch reaction) exhibited a doughnut-shaped horizontal distribution. These results suggest that OH aq, among the plasma-produced oxidizing species, represents the dominant factor in plasma-induced cell permeabilization. These results enhance the current understanding of the mechanism of APP as a cell-permeabilization tool. (paper)

  13. Lipocalin 2 Enhances Migration and Resistance against Cisplatin in Endometrial Carcinoma Cells.

    Science.gov (United States)

    Miyamoto, Tsutomu; Kashima, Hiroyasu; Yamada, Yasushi; Kobara, Hisanori; Asaka, Ryoichi; Ando, Hirofumi; Higuchi, Shotaro; Ida, Koichi; Mvunta, David Hamisi; Shiozawa, Tanri

    2016-01-01

    Lipocalin 2 (LCN2) is a secretory protein that is involved in various physiological processes including iron transport. We previously identified LCN2 as an up-regulated gene in endometrial carcinoma, and found that the overexpression of LCN2 and its receptor, SLC22A17, was associated with a poor prognosis. However, the functions and mechanism of action of LCN2 currently remain unclear. The LCN2-overexpressing endometrial carcinoma cell lines, HHUA and RL95-2, and LCN2-low-expressing one, HEC1B, were used. The effects of LCN2 on cell migration, cell viability, and apoptosis under various stresses, including ultraviolet (UV) irradiation and cisplatin treatment, were examined using the scratch wound healing assay, WST-1 assay, and Apostrand assay, respectively. LCN2-silencing using shRNA method significantly reduced the migration ability of cells (pendometrial carcinoma cells under various stresses in an iron-dependent manner. The survival function of LCN2 may be exerted through the PI3K pathway and suppression of the p53-p21 pathway. These functions of LCN2 may increase the malignant potential of endometrial carcinoma cells.

  14. A Critical Role of IL-21-Induced BATF in Sustaining CD8-T-Cell-Mediated Chronic Viral Control

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    Gang Xin

    2015-11-01

    Full Text Available Control of chronic viral infections by CD8 T cells is critically dependent on CD4 help. In particular, helper-derived IL-21 plays a key role in sustaining the CD8 T cell response; however, the molecular pathways by which IL-21 sustains CD8 T cell immunity remain unclear. We demonstrate that IL-21 causes a phenotypic switch of transcription factor expression in CD8 T cells during chronic viral infection characterized by sustained BATF expression. Importantly, BATF expression during chronic infection is both required for optimal CD8 T cell persistence and anti-viral effector function and sufficient to rescue “unhelped” CD8 T cells. Mechanistically, BATF sustains the response by cooperating with IRF4, an antigen-induced transcription factor that is also critically required for CD8 T cell maintenance, to preserve Blimp-1 expression and thereby sustain CD8 T cell effector function. Collectively, these data suggest that CD4 T cells “help” the CD8 response during chronic infection via IL-21-induced BATF expression.

  15. Identification of genes associated with cisplatin resistance in human oral squamous cell carcinoma cell line

    OpenAIRE

    Zhang Ping; Zhang Zhiyuan; Zhou Xiaojian; Qiu Weiliu; Chen Fangan; Chen Wantao

    2006-01-01

    Abstract Background Cisplatin is widely used for chemotherapy of head and neck squamous cell carcinoma. However, details of the molecular mechanism responsible for cisplatin resistance are still unclear. The aim of this study was to identify the expression of genes related to cisplatin resistance in oral squamous cell carcinoma cells. Methods A cisplatin-resistant cell line, Tca/cisplatin, was established from a cisplatin-sensitive cell line, Tca8113, which was derived from moderately-differe...

  16. Long-term persistence and function of hematopoietic stem cell-derived chimeric antigen receptor T cells in a nonhuman primate model of HIV/AIDS.

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    Anjie Zhen

    2017-12-01

    Full Text Available Chimeric Antigen Receptor (CAR T-cells have emerged as a powerful immunotherapy for various forms of cancer and show promise in treating HIV-1 infection. However, significant limitations are persistence and whether peripheral T cell-based products can respond to malignant or infected cells that may reappear months or years after treatment remains unclear. Hematopoietic Stem/Progenitor Cells (HSPCs are capable of long-term engraftment and have the potential to overcome these limitations. Here, we report the use of a protective CD4 chimeric antigen receptor (C46CD4CAR to redirect HSPC-derived T-cells against simian/human immunodeficiency virus (SHIV infection in pigtail macaques. CAR-containing cells persisted for more than 2 years without any measurable toxicity and were capable of multilineage engraftment. Combination antiretroviral therapy (cART treatment followed by cART withdrawal resulted in lower viral rebound in CAR animals relative to controls, and demonstrated an immune memory-like response. We found CAR-expressing cells in multiple lymphoid tissues, decreased tissue-associated SHIV RNA levels, and substantially higher CD4/CD8 ratios in the gut as compared to controls. These results show that HSPC-derived CAR T-cells are capable of long-term engraftment and immune surveillance. This study demonstrates for the first time the safety and feasibility of HSPC-based CAR therapy in a large animal preclinical model.

  17. Establishment of a novel high-affinity IgE receptor-positive canine mast cell line with wild-type c-kit receptors

    International Nuclear Information System (INIS)

    Amagai, Yosuke; Tanaka, Akane; Ohmori, Keitaro; Matsuda, Hiroshi

    2008-01-01

    Much is known regarding participations of mast cells with innate and acquired immunity by secreting various cytokines and chemical mediators. However, details of mast cell biology still remain unclear. In this study, we successfully established a novel growth factor-independent mast cell line (MPT-1) derived from canine mast cell tumor. MPT-1 cells manifested factor-independent proliferation as floating cells containing a large amount of histamine, as well as chymase-like dog mast cell protease 3, in cytosolic granules. Particularly, MPT-1 cells expressed high-affinity IgE receptors (FcεRI) and wild-type c-kit receptors. Degranulation of MPT-1 cells was induced not only by stimulation with calcium ionophore but also by cross-linkage of the surface IgE. Given that MPT-1 is the first mast cell line with FcεRI which has no c-kit mutations, MPT-1 cells may provide great contribution for investigation of IgE-mediated activation mechanisms of mast cells, leading to development of effective treatment for allergic disorders

  18. Mitochondrial permeability transition and cell death: the role of cyclophilin D

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    Sabzali eJavadov

    2013-04-01

    Full Text Available Mitochondria serve as a powerhouse which provides near 90% of ATP necessary for cell life. However, recent studies provide strong evidence that mitochondria also play a central role in cell death. Irreversible mitochondrial permeability transition (mPT at high conductance in response to oxidative or other cellular stresses is accompanied by formation of pathological and non-specific mPT pores (mPTP in the inner membrane of mitochondria. Mitochondrial PTP can serve as a target to prevent cell death under pathological conditions such as cardiac and brain ischemia/reperfusion injury and diabetes. On the other hand, mPTP can be used as an executioner to specifically induce cell death thus blocking tumorigenesis in cancer diseases. Despite many studies, the molecular identity of the mPTP remains unclear. At present, cyclophilin D (CyP-D represents the only mPTP protein which plays an essential role in pore formation. This review will discuss direct and indirect mechanisms underlying CyP-D interaction with a target protein of the mPTP complex. Understanding of the mechanisms of mPTP formation will be helpful to further develop new pharmacological agents targeting mitochondria-mediated cell death.

  19. Hedgehog signaling acts with the temporal cascade to promote neuroblast cell cycle exit.

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    Phing Chian Chai

    Full Text Available In Drosophila postembryonic neuroblasts, transition in gene expression programs of a cascade of transcription factors (also known as the temporal series acts together with the asymmetric division machinery to generate diverse neurons with distinct identities and regulate the end of neuroblast proliferation. However, the underlying mechanism of how this "temporal series" acts during development remains unclear. Here, we show that Hh signaling in the postembryonic brain is temporally regulated; excess (earlier onset of Hh signaling causes premature neuroblast cell cycle exit and under-proliferation, whereas loss of Hh signaling causes delayed cell cycle exit and excess proliferation. Moreover, the Hh pathway functions downstream of Castor but upstream of Grainyhead, two components of the temporal series, to schedule neuroblast cell cycle exit. Interestingly, hh is likely a target of Castor. Hence, Hh signaling provides a link between the temporal series and the asymmetric division machinery in scheduling the end of neurogenesis.

  20. BID links ferroptosis to mitochondrial cell death pathways

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    Sandra Neitemeier

    2017-08-01

    Full Text Available Ferroptosis has been defined as an oxidative and iron-dependent pathway of regulated cell death that is distinct from caspase-dependent apoptosis and established pathways of death receptor-mediated regulated necrosis. While emerging evidence linked features of ferroptosis induced e.g. by erastin-mediated inhibition of the Xc- system or inhibition of glutathione peroxidase 4 (Gpx4 to an increasing number of oxidative cell death paradigms in cancer cells, neurons or kidney cells, the biochemical pathways of oxidative cell death remained largely unclear. In particular, the role of mitochondrial damage in paradigms of ferroptosis needs further investigation.In the present study, we find that erastin-induced ferroptosis in neuronal cells was accompanied by BID transactivation to mitochondria, loss of mitochondrial membrane potential, enhanced mitochondrial fragmentation and reduced ATP levels. These hallmarks of mitochondrial demise are also established features of oxytosis, a paradigm of cell death induced by Xc- inhibition by millimolar concentrations of glutamate. Bid knockout using CRISPR/Cas9 approaches preserved mitochondrial integrity and function, and mediated neuroprotective effects against both, ferroptosis and oxytosis. Furthermore, the BID-inhibitor BI-6c9 inhibited erastin-induced ferroptosis, and, in turn, the ferroptosis inhibitors ferrostatin-1 and liproxstatin-1 prevented mitochondrial dysfunction and cell death in the paradigm of oxytosis. These findings show that mitochondrial transactivation of BID links ferroptosis to mitochondrial damage as the final execution step in this paradigm of oxidative cell death. Keywords: Ferroptosis, BID, Mitochondria, CRISPR, Oxytosis, Neuronal death

  1. Activation of iNKT Cells Prevents Salmonella-Enterocolitis and Salmonella-Induced Reactive Arthritis by Downregulating IL-17-Producing γδT Cells

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    Mariángeles Noto Llana

    2017-09-01

    Full Text Available Reactive arthritis (ReA is an inflammatory condition of the joints that arises following an infection. Salmonella enterocolitis is one of the most common infections leading to ReA. Although the pathogenesis remains unclear, it is known that IL-17 plays a pivotal role in the development of ReA. IL-17-producers cells are mainly Th17, iNKT, and γδT lymphocytes. It is known that iNKT cells regulate the development of Th17 lineage. Whether iNKT cells also regulate γδT lymphocytes differentiation is unknown. We found that iNKT cells play a protective role in ReA. BALB/c Jα18−/− mice suffered a severe Salmonella enterocolitis, a 3.5-fold increase in IL-17 expression and aggravated inflammation of the synovial membrane. On the other hand, activation of iNKT cells with α-GalCer abrogated IL-17 response to Salmonella enterocolitis and prevented intestinal and joint tissue damage. Moreover, the anti-inflammatory effect of α-GalCer was related to a drop in the proportion of IL-17-producing γδT lymphocytes (IL17-γδTcells rather than to a decrease in Th17 cells. In summary, we here show that iNKT cells play a protective role against Salmonella-enterocolitis and Salmonella-induced ReA by downregulating IL17-γδTcells.

  2. Glutamine deficiency induces DNA alkylation damage and sensitizes cancer cells to alkylating agents through inhibition of ALKBH enzymes.

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    Thai Q Tran

    2017-11-01

    Full Text Available Driven by oncogenic signaling, glutamine addiction exhibited by cancer cells often leads to severe glutamine depletion in solid tumors. Despite this nutritional environment that tumor cells often experience, the effect of glutamine deficiency on cellular responses to DNA damage and chemotherapeutic treatment remains unclear. Here, we show that glutamine deficiency, through the reduction of alpha-ketoglutarate, inhibits the AlkB homolog (ALKBH enzymes activity and induces DNA alkylation damage. As a result, glutamine deprivation or glutaminase inhibitor treatment triggers DNA damage accumulation independent of cell death. In addition, low glutamine-induced DNA damage is abolished in ALKBH deficient cells. Importantly, we show that glutaminase inhibitors, 6-Diazo-5-oxo-L-norleucine (DON or CB-839, hypersensitize cancer cells to alkylating agents both in vitro and in vivo. Together, the crosstalk between glutamine metabolism and the DNA repair pathway identified in this study highlights a potential role of metabolic stress in genomic instability and therapeutic response in cancer.

  3. Glutamine deficiency induces DNA alkylation damage and sensitizes cancer cells to alkylating agents through inhibition of ALKBH enzymes.

    Science.gov (United States)

    Tran, Thai Q; Ishak Gabra, Mari B; Lowman, Xazmin H; Yang, Ying; Reid, Michael A; Pan, Min; O'Connor, Timothy R; Kong, Mei

    2017-11-01

    Driven by oncogenic signaling, glutamine addiction exhibited by cancer cells often leads to severe glutamine depletion in solid tumors. Despite this nutritional environment that tumor cells often experience, the effect of glutamine deficiency on cellular responses to DNA damage and chemotherapeutic treatment remains unclear. Here, we show that glutamine deficiency, through the reduction of alpha-ketoglutarate, inhibits the AlkB homolog (ALKBH) enzymes activity and induces DNA alkylation damage. As a result, glutamine deprivation or glutaminase inhibitor treatment triggers DNA damage accumulation independent of cell death. In addition, low glutamine-induced DNA damage is abolished in ALKBH deficient cells. Importantly, we show that glutaminase inhibitors, 6-Diazo-5-oxo-L-norleucine (DON) or CB-839, hypersensitize cancer cells to alkylating agents both in vitro and in vivo. Together, the crosstalk between glutamine metabolism and the DNA repair pathway identified in this study highlights a potential role of metabolic stress in genomic instability and therapeutic response in cancer.

  4. Transport of polyamines in Drosophila S2 cells: kinetics, pharmacology and dependence on the plasma membrane proton gradient.

    Science.gov (United States)

    Romero-Calderón, Rafael; Krantz, David E

    2006-01-15

    Polyamine transport activities have been described in diverse multicellular systems, but their bioenergetic mechanisms and molecular identity remain unclear. In the present paper, we describe a high-affinity spermine/spermidine transport activity expressed in Drosophila S2 cells. Ion-replacement experiments indicate that polyamine uptake across the cell membrane is Na+-, K+-, Cl-- and Ca2+-independent, but pH-sensitive. Additional experiments using ionophores suggest that polyamine uptake may be H+-coupled. Pharmacological experiments show that polyamine uptake in S2 cells is selectively blocked by MGBG {methylglyoxal bis(guanylhydrazone) or 1,1'-[(methylethanediylidine)-dinitrilo]diguanidine} and paraquat (N,N-dimethyl-4,4'-bipyridylium), two known inhibitors of polyamine uptake in mammalian cells. In addition, inhibitors known to block the Slc22 (solute carrier 22) family of organic anion/cation transporters inhibit spermine uptake in S2 cells. These data and the genetic tools available in Drosophila will facilitate the molecular identification and further characterization of this activity.

  5. Inhibitory effect of luteolin on estrogen biosynthesis in human ovarian granulosa cells by suppression of aromatase (CYP19).

    Science.gov (United States)

    Lu, Dan-feng; Yang, Li-juan; Wang, Fei; Zhang, Guo-lin

    2012-08-29

    Inhibition of aromatase, the key enzyme in estrogen biosynthesis, is an important strategy in the treatment of breast cancer. Several dietary flavonoids show aromatase inhibitory activity, but their tissue specificity and mechanism remain unclear. This study found that the dietary flavonoid luteolin potently inhibited estrogen biosynthesis in a dose- and time-dependent manner in KGN cells derived from human ovarian granulosa cells, the major source of estrogens in premenopausal women. Luteolin decreased aromatase mRNA and protein expression in KGN cells. Luteolin also promoted aromatase protein degradation and inhibited estrogen biosynthesis in aromatase-expressing HEK293A cells, but had no effect on recombinant expressed aromatase. Estrogen biosynthesis in KGN cells was inhibited with differing potencies by extracts of onion and bird chili and by four other dietary flavonoids: kaempferol, quercetin, myricetin, and isorhamnetin. The present study suggests that luteolin inhibits estrogen biosynthesis by decreasing aromatase expression and destabilizing aromatase protein, and it warrants further investigation as a potential treatment for estrogen-dependent cancers.

  6. Up-Regulation of the Lymphatic Marker Podoplanin, a Mucin-Type Transmembrane Glycoprotein, in Human Squamous Cell Carcinomas and Germ Cell Tumors

    Science.gov (United States)

    Schacht, Vivien; Dadras, Soheil S.; Johnson, Louise A.; Jackson, David G.; Hong, Young-Kwon; Detmar, Michael

    2005-01-01

    The mucin-type glycoprotein podoplanin is specifically expressed by lymphatic but not blood vascular endothelial cells in culture and in tumor-associated lymphangiogenesis, and podoplanin deficiency results in congenital lymphedema and impaired lymphatic vascular patterning. However, research into the biological importance of podoplanin has been hampered by the lack of a generally available antibody against the human protein, and its expression in normal tissues and in human malignancies has remained unclear. We generated a human podoplanin-Fc fusion protein and found that the commercially available mouse monoclonal antibody D2-40 specifically recognized human podoplanin, as assessed by enzyme-linked immunosorbent assay and Western blot analyses. We found that, in addition to lymphatic endothelium, podoplanin was also expressed by peritoneal mesothelial cells, osteocytes, glandular myoepithelial cells, ependymal cells, and by stromal reticular cells and follicular dendritic cells of lymphoid organs. These findings were confirmed in normal mouse tissues with anti-podoplanin antibody 8.1.1. Podoplanin was also strongly expressed by granulosa cells in normal ovarian follicles, and by ovarian dysgerminomas and granulosa cell tumors. Although podoplanin was primarily absent from normal human epidermis, its expression was strongly induced in 22 of 28 squamous cell carcinomas studied. These findings suggest a potential role of podoplanin in tumor progression, and they also identify the first commercially available antibody for the specific staining of a defined lymphatic marker in archival human tissue sections, thereby enabling more widespread studies of tumor lymphangiogenesis in human cancers. PMID:15743802

  7. Estrogen deficiency heterogeneously affects tissue specific stem cells in mice

    Science.gov (United States)

    Kitajima, Yuriko; Doi, Hanako; Ono, Yusuke; Urata, Yoshishige; Goto, Shinji; Kitajima, Michio; Miura, Kiyonori; Li, Tao-Sheng; Masuzaki, Hideaki

    2015-01-01

    Postmenopausal disorders are frequently observed in various organs, but their relationship with estrogen deficiency and mechanisms remain unclear. As tissue-specific stem cells have been found to express estrogen receptors, we examined the hypothesis that estrogen deficiency impairs stem cells, which consequently contributes to postmenopausal disorders. Six-week-old C57BL/6 female mice were ovariectomized, following which they received 17β-estradiol replacement or vehicle (control). Sham-operated mice were used as healthy controls. All mice were killed for evaluation 2 months after treatments. Compared with the healthy control, ovariectomy significantly decreased uterine weight, which was partially recovered by 17β-estradiol replacement. Ovariectomy significantly increased the numbers of c-kit-positive hematopoietic stem/progenitor cells in bone marrow, but impaired their capacity to grow mixed cell-type colonies in vitro. Estrogen replacement further increased the numbers of c-kit-positive hematopoietic stem/progenitor cells in bone marrow, without significantly affecting colony growth in vitro. The number of CD105-positive mesenchymal stem cells in bone marrow also significantly decreased after ovariectomy, but completely recovered following estrogen replacement. Otherwise, neither ovariectomy nor estrogen replacement changed the number of Pax7-positive satellite cells, which are a skeletal muscle-type stem cell. Estrogen deficiency heterogeneously affected tissue-specific stem cells, suggesting a likely and direct relationship with postmenopausal disorders. PMID:26245252

  8. Human natural killer cells prevent infectious mononucleosis features by targeting lytic Epstein-Barr virus infection.

    Science.gov (United States)

    Chijioke, Obinna; Müller, Anne; Feederle, Regina; Barros, Mario Henrique M; Krieg, Carsten; Emmel, Vanessa; Marcenaro, Emanuela; Leung, Carol S; Antsiferova, Olga; Landtwing, Vanessa; Bossart, Walter; Moretta, Alessandro; Hassan, Rocio; Boyman, Onur; Niedobitek, Gerald; Delecluse, Henri-Jacques; Capaul, Riccarda; Münz, Christian

    2013-12-26

    Primary infection with the human oncogenic Epstein-Barr virus (EBV) can result in infectious mononucleosis (IM), a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK) cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  9. T cells exacerbate Lyme borreliosis in TLR2-deficient mice

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    Carrie E. Lasky

    2016-11-01

    Full Text Available Infection of humans with the spirochete, Borrelia burgdorferi, causes Lyme borreliosis and can lead to clinical manifestations such as, arthritis, carditis and neurological conditions. Experimental infection of mice recapitulates many of these symptoms and serves as a model system for the investigation of disease pathogenesis and immunity. Innate immunity is known to drive the development of Lyme arthritis and carditis, but the mechanisms driving this response remain unclear. Innate immune cells recognize B. burgdorferi surface lipoproteins primarily via Toll-like receptor (TLR2; however, previous work has demonstrated TLR2-/- mice had exacerbated disease and increased bacterial burden. We demonstrate increased CD4 and CD8 T cell infiltrates in B. burgdorferi-infected joints and hearts of C3H TLR2-/- mice. In vivo depletion of either CD4 or CD8 T cells reduced Borrelia-induced joint swelling and lowered tissue spirochete burden, while depletion of CD8 T cells alone reduced disease severity scores. Exacerbation of Lyme arthritis correlated with increased production of CXCL9 by synoviocytes and this was reduced with CD8 T cell depletion. These results demonstrate T cells can exacerbate Lyme disease pathogenesis and prolong disease resolution possibly through dysregulation of inflammatory responses and inhibition of bacterial clearance.

  10. MAIT cells are reduced in frequency and functionally impaired in human T lymphotropic virus type 1 infection: Potential clinical implications.

    Science.gov (United States)

    Paquin-Proulx, Dominic; Greenspun, Benjamin C; Costa, Emanuela A S; Segurado, Aluisio C; Kallas, Esper G; Nixon, Douglas F; Leal, Fabio E

    2017-01-01

    HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develop HAM/TSP. The cellular immune response has been implicated in the development of inflammatory alterations in these patients; however the pathogenic mechanisms for disease progression remain unclear. Furthermore, HTLV-1-infected individuals have an increase incidence of Mycobacterium tuberculosis (Mtb) infection, suggesting that immunological defect are associated with HTLV-1 infection. Evidence suggests an important role for Mucosal-associated invariant T (MAIT) cells in the early control of Mtb infection. Chronic viral infections like HIV and HCV have been associated with decreased frequency and functionality of MAIT cells. We hypothesized that HTLV-1 infection is associated with similar perturbations in MAIT cells. We investigated MAIT cell frequency, phenotype, and function by flow cytometry in a cohort of 10 asymptomatic and 10 HAM/TSP HTLV-1 infected patients. We found that MAIT cells from HTLV-1-infected subjects were reduced and showed high co-expression of the activation markers CD38 and HLA-DR but normal levels of CCR6 and CD127. MAIT cells had a lower expression of the transcription factor PLZF in HAM/TSP patients. Unlike Tax-specific CD8+T cells, which are hyperfunctional, MAIT cells from HTLV-1-infected subjects had a poor IFNγ response following antigen stimulation. MAIT cell perturbations in HTLV-1 infection were not associated with HTLV-1 proviral load and MAIT cells were not infected by HTLV-1 in vivo. Rather, MAIT cells loss was associated with immune activation. Overall, our results do not support a role for MAIT cells in HAM/TSP pathogenesis but reduced numbers of MAIT cells, together with their poor functionality, could contribute to the increased susceptibility of HTLV-1-infected individuals to other infectious

  11. Effects of external radiation in a co-culture model of endothelial cells and adipose-derived stem cells

    International Nuclear Information System (INIS)

    Haubner, Frank; Leyh, Michaela; Ohmann, Elisabeth; Pohl, Fabian; Prantl, Lukas; Gassner, Holger G

    2013-01-01

    The inflammatory response clinically observed after radiation has been described to correlate with elevated expression of cytokines and adhesion molecules by endothelial cells. Therapeutic compensation for this microvascular compromise could be an important approach in the treatment of irradiated wounds. Clinical reports describe the potential of adipose-derived stem cells to enhance wound healing, but the underlying cellular mechanisms remain largely unclear. Human dermal microvascular endothelial cells (HDMEC) and human adipose-derived stem cells (ASC) were cultured in a co-culture setting and irradiated with sequential doses of 2 to 12 Gy. Cell count was determined 48 h after radiation using a semi-automated cell counting system. Levels of interleukin-6 (IL-6), basic fibroblast growth factor (FGF), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were determined in the supernatants using enzyme-linked immunosorbent assay (ELISA). Irradiated HDMEC and ASC as well as non-irradiated co-cultures, HDMEC or ASC respectively were used as controls. Cell count was significantly reduced in irradiated co-cultures of HDMEC and ASC compared to non-irradiated controls. Levels of IL-6, FGF, ICAM-1 and VCAM-1 in the supernatants of the co-cultures were significantly less affected by external radiation in comparison to HDMEC. The increased expression of cytokines and adhesion molecules by HDMEC after external radiation is mitigated in the co-culture setting with ASC. These in vitro changes seem to support the clinical observation that ASC may have a stabilizing effect when injected into irradiated wounds

  12. Reversibility of β-Cell-Specific Transcript Factors Expression by Long-Term Caloric Restriction in db/db Mouse

    Directory of Open Access Journals (Sweden)

    Chunjun Sheng

    2016-01-01

    Full Text Available Type 2 diabetes (T2D is characterized by β-cell dedifferentiation, but underlying mechanisms remain unclear. The purpose of the current study was to explore the mechanisms of β-cell dedifferentiation with and without long-term control of calorie intake. We used a diabetes mouse model (db/db to analyze the changes in the expression levels of β-cell-specific transcription factors (TFs and functional factors with long-term caloric restriction (CR. Our results showed that chronic euglycemia was maintained in the db/db mice with long-term CR intervention, and β-cell dedifferentiation was significantly reduced. The expression of Glut2, Pdx1, and Nkx6.1 was reversed, while MafA expression was significantly increased with long-term CR. GLP-1 pathway was reactivated with long-term CR. Our work showed that the course of β-cell dedifferentiation can intervene by long-term control of calorie intake. Key β-cell-specific TFs and functional factors play important roles in maintaining β-cell differentiation. Targeting these factors could optimize T2D therapies.

  13. Mineralized remains of morphotypes of filamentous cyanobacteria in carbonaceous meteorites

    Science.gov (United States)

    Hoover, Richard B.

    2005-09-01

    rocks, living, cryopreserved and fossilized extremophiles and cyanobacteria. These studies have resulted in the detection of mineralized remains of morphotypes of filamentous cyanobacteria, mats and consortia in many carbonaceous meteorites. These well-preserved and embedded microfossils are consistent with the size, morphology and ultra-microstructure of filamentous trichomic prokaryotes and degraded remains of microfibrils of cyanobacterial sheaths. EDAX elemental studies reveal that the forms in the meteorites often have highly carbonized sheaths in close association with permineralized filaments, trichomes, and microbial cells. The eextensive protocols and methodologies that have been developed to protect the samples from contamination and to distinguish recent contaminants from indigenous microfossils are described recent bio-contaminants. Ratios of critical bioelements (C:O, C:N, C:P, and C:S) reveal dramatic differences between microfossils in Earth rocks and meteorites and in the cells, filaments, trichomes, and hormogonia of recently living cyanobacteria. The results of comparative optical, ESEM and FESEM studies and EDAX elemental analyses of recent cyanobacteria (e.g. Calothrix, Oscillatoria, and Lyngbya) of similar size, morphology and microstructure to microfossils found embedded in the Murchison CM2 and the Orgueil CI1 carbonaceous meteorites are presented

  14. Transcriptional Reprogramming during Effector-to-Memory Transition Renders CD4+ T Cells Permissive for Latent HIV-1 Infection.

    Science.gov (United States)

    Shan, Liang; Deng, Kai; Gao, Hongbo; Xing, Sifei; Capoferri, Adam A; Durand, Christine M; Rabi, S Alireza; Laird, Gregory M; Kim, Michelle; Hosmane, Nina N; Yang, Hung-Chih; Zhang, Hao; Margolick, Joseph B; Li, Linghua; Cai, Weiping; Ke, Ruian; Flavell, Richard A; Siliciano, Janet D; Siliciano, Robert F

    2017-10-17

    The latent reservoir for HIV-1 in resting memory CD4 + T cells is the major barrier to curing HIV-1 infection. Studies of HIV-1 latency have focused on regulation of viral gene expression in cells in which latent infection is established. However, it remains unclear how infection initially becomes latent. Here we described a unique set of properties of CD4 + T cells undergoing effector-to-memory transition including temporary upregulation of CCR5 expression and rapid downregulation of cellular gene transcription. These cells allowed completion of steps in the HIV-1 life cycle through integration but suppressed HIV-1 gene transcription, thus allowing the establishment of latency. CD4 + T cells in this stage were substantially more permissive for HIV-1 latent infection than other CD4 + T cells. Establishment of latent HIV-1 infection in CD4 + T could be inhibited by viral-specific CD8 + T cells, a result with implications for elimination of latent HIV-1 infection by T cell-based vaccines. Copyright © 2017. Published by Elsevier Inc.

  15. Temporal dynamics and transcriptional control using single-cell gene expression analysis.

    Science.gov (United States)

    Kouno, Tsukasa; de Hoon, Michiel; Mar, Jessica C; Tomaru, Yasuhiro; Kawano, Mitsuoki; Carninci, Piero; Suzuki, Harukazu; Hayashizaki, Yoshihide; Shin, Jay W

    2013-01-01

    Changes in environmental conditions lead to expression variation that manifest at the level of gene regulatory networks. Despite a strong understanding of the role noise plays in synthetic biological systems, it remains unclear how propagation of expression heterogeneity in an endogenous regulatory network is distributed and utilized by cells transitioning through a key developmental event. Here we investigate the temporal dynamics of a single-cell transcriptional network of 45 transcription factors in THP-1 human myeloid monocytic leukemia cells undergoing differentiation to macrophages. We systematically measure temporal regulation of expression and variation by profiling 120 single cells at eight distinct time points, and infer highly controlled regulatory modules through which signaling operates with stochastic effects. This reveals dynamic and specific rewiring as a cellular strategy for differentiation. The integration of both positive and negative co-expression networks further identifies the proto-oncogene MYB as a network hinge to modulate both the pro- and anti-differentiation pathways. Compared to averaged cell populations, temporal single-cell expression profiling provides a much more powerful technique to probe for mechanistic insights underlying cellular differentiation. We believe that our approach will form the basis of novel strategies to study the regulation of transcription at a single-cell level.

  16. Neuroendocrine cells during human prostate development: does neuroendocrine cell density remain constant during fetal as well as postnatal life?

    NARCIS (Netherlands)

    Xue, Y.; van der Laak, J.; Smedts, F.; Schoots, C.; Verhofstad, A.; de la Rosette, J.; Schalken, J.

    2000-01-01

    Knowledge concerning differentiation of neuroendocrine (NE) cells during development of the human prostate is rather fragmentary. Using immunohistochemistry combined with a morphometric method, we investigated the distribution and density of NE cells in the developing human prostate, with special

  17. Nitric oxide released from JS-K induces cell death by mitotic catastrophe as part of necrosis in glioblastoma multiforme.

    Science.gov (United States)

    Günzle, Jessica; Osterberg, Nadja; Saavedra, Joseph E; Weyerbrock, Astrid

    2016-09-01

    The nitric oxide (NO) donor JS-K is specifically activated by glutathione S-transferases (GSTs) in GST-overexpressing cells. We have shown the induction of cell death in glioblastoma multiforme (GBM) cells at high JS-K doses but the mechanism remains unclear. The aim of this study was to determine whether NO-induced cell death is triggered by induction of apoptotic or necrotic pathways. For the first time, we demonstrate that NO induces cell death via mitotic catastrophe (MC) with non-apoptotic mechanisms in GBM cells. Moreover, the level of morphological changes indicating MC correlates with increased necrosis. Therefore, we conclude that MC is the main mechanism by which GBM cells undergo cell death after treatment with JS-K associated with necrosis rather than apoptosis. In addition, we show that PARP1 is not an exclusive marker for late apoptosis but is also involved in MC. Activating an alternative way of cell death can be useful for the multimodal cancer therapy of GBM known for its strong anti-apoptotic mechanisms and drug resistance.

  18. Establishment of prostate cancer spheres from a prostate cancer cell line after phenethyl isothiocyanate treatment and discovery of androgen-dependent reversible differentiation between sphere and neuroendocrine cells.

    Science.gov (United States)

    Chen, Yamei; Cang, Shundong; Han, Liying; Liu, Christina; Yang, Patrick; Solangi, Zeeshan; Lu, Quanyi; Liu, Delong; Chiao, J W

    2016-05-03

    Prostate cancer can transform from androgen-responsive to an androgen-independent phenotype. The mechanism responsible for the transformation remains unclear. We studied the effects of an epigenetic modulator, phenethyl isothiocyanate (PEITC), on the androgen-responsive LNCaP cells. After treatment with PEITC, floating spheres were formed with characteristics of prostate cancer stem cells (PCSC). These spheres were capable of self-renewal in media with and without androgen. They have been maintained in both types of media as long term cultures. Upon androgen deprivation, the adherent spheres differentiated to neuroendocrine cells (NEC) with decreased proliferation, expression of androgen receptor, and PSA. NEC reverse differentiated to spheres when androgen was replenished. The sphere cells expressed surface marker CD44 and had enhanced histone H3K4 acetylation, DNMT1 down-regulation and GSTP1 activation. We hypothesize that PEITC-mediated alteration in epigenomics of LNCaP cells may give rise to sphere cells, whereas reversible androgenomic alterations govern the shuttling between sphere PCSC and progeny NEC. Our findings identify unrecognized properties of prostate cancer sphere cells with multi-potential plasticity. This system will facilitate development of novel therapeutic agents and allow further exploration into epigenomics and androgenomics governing the transformation to hormone refractory prostate cancer.

  19. Involvement of HIF-1α activation in the doxorubicin resistance of human osteosarcoma cells.

    Science.gov (United States)

    Roncuzzi, Laura; Pancotti, Fabia; Baldini, Nicola

    2014-07-01

    Osteosarcoma is the most common primary bone cancer in children and adolescents. Despite aggressive treatment regimens, survival outcomes remain unsatisfactory, particularly in patients with metastatic and/or recurrent disease. Unfortunately, treatment failure is commonly due to the development of chemoresistance, for which the underlying molecular mechanisms remain unclear. The aim of the present study was to investigate the role of hypoxia-inducible factor 1α (HIF‑1α) and its signalling pathways as mediators of drug-resistance in human osteosarcoma. Toward this aim, we established two osteosarcoma cell lines selected for resistance to doxorubicin, a drug of choice in the treatment of this tumour. Our results showed that the multidrug resistance (MDR) phenotype was also mediated by HIF-1α, the most important regulator of cell adaptation to hypoxia. Our data showed that this transcription factor promoted the outward transport of intracellular doxorubicin by activating the P-glycoprotein (P-gp) expression in osteosarcoma cells maintained in normoxic conditions. In addition, it hindered doxorubicin-induced apoptosis by regulating the expression of c-Myc and p21. Finally, we observed that the doxorubicin-resistant cells maintained for 2 months of continuous culture in a drug-free medium, lost their drug-resistance and this effect was associated with the absence of HIF-1α expression. The emerging role of HIF-1α in osteosarcoma biology indicates its use as a valuable therapeutic target.

  20. Alterations in cellular metabolism modulate CD1d-mediated NKT-cell responses.

    Science.gov (United States)

    Webb, Tonya J; Carey, Gregory B; East, James E; Sun, Wenji; Bollino, Dominique R; Kimball, Amy S; Brutkiewicz, Randy R

    2016-08-01

    Natural killer T (NKT) cells play a critical role in the host's innate immune response. CD1d-mediated presentation of glycolipid antigens to NKT cells has been established; however, the mechanisms by which NKT cells recognize infected or cancerous cells remain unclear. 5(')-AMP activated protein kinase (AMPK) is a master regulator of lipogenic pathways. We hypothesized that activation of AMPK during infection and malignancy could alter the repertoire of antigens presented by CD1d and serve as a danger signal to NKT cells. In this study, we examined the effect of alterations in metabolism on CD1d-mediated antigen presentation to NKT cells and found that an infection with lymphocytic choriomeningitis virus rapidly increased CD1d-mediated antigen presentation. Hypoxia inducible factors (HIF) enhance T-cell effector functions during infection, therefore antigen presenting cells pretreated with pharmacological agents that inhibit glycolysis, induce HIF and activate AMPK were assessed for their ability to induce NKT-cell responses. Pretreatment with 2-deoxyglucose, cobalt chloride, AICAR and metformin significantly enhanced CD1d-mediated NKT-cell activation. In addition, NKT cells preferentially respond to malignant B cells and B-cell lymphomas express HIF-1α. These data suggest that targeting cellular metabolism may serve as a novel means of inducing innate immune responses. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Mass spectrometry-based metabolic profiling of gemcitabine-sensitive and gemcitabine-resistant pancreatic cancer cells.

    Science.gov (United States)

    Fujimura, Yoshinori; Ikenaga, Naoki; Ohuchida, Kenoki; Setoyama, Daiki; Irie, Miho; Miura, Daisuke; Wariishi, Hiroyuki; Murata, Masaharu; Mizumoto, Kazuhiro; Hashizume, Makoto; Tanaka, Masao

    2014-03-01

    Gemcitabine resistance (GR) is one of the critical issues for therapy for pancreatic cancer, but the mechanism still remains unclear. Our aim was to increase the understanding of GR by metabolic profiling approach. To establish GR cells, 2 human pancreatic cancer cell lines, SUIT-2 and CAPAN-1, were exposed to increasing concentration of gemcitabine. Both parental and chemoresistant cells obtained by this treatment were subjected to metabolic profiling based on liquid chromatography-mass spectrometry. Multivariate statistical analyses, both principal component analysis and orthogonal partial least squares discriminant analysis, distinguished metabolic signature of responsiveness and resistance to gemcitabine in both SUIT-2 and CAPAN-1 cells. Among significantly different (P metabolic pathways such as amino acid, nucleotide, energy, cofactor, and vitamin pathways. Decreases in glutamine and proline levels as well as increases in aspartate, hydroxyproline, creatine, and creatinine levels were observed in chemoresistant cells from both cell lines. These results suggest that metabolic profiling can isolate distinct features of pancreatic cancer in the metabolome of gemcitabine-sensitive and GR cells. These findings may contribute to the biomarker discovery and an enhanced understanding of GR in pancreatic cancer.

  2. Development of an in vitro culture method for stepwise differentiation of mouse embryonic stem cells and induced pluripotent stem cells into mature osteoclasts.

    Science.gov (United States)

    Nishikawa, Keizo; Iwamoto, Yoriko; Ishii, Masaru

    2014-05-01

    The development of methods for differentiation of embryonic stem cells (ESCs) and induced pluripotent stem cell (iPSCs) into functional cells have helped to analyze the mechanism regulating cellular processes and to explore cell-based assays for drug discovery. Although several reports have demonstrated methods for differentiation of mouse ESCs into osteoclast-like cells, it remains unclear whether these methods are applicable for differentiation of iPSCs to osteoclasts. In this study, we developed a simple method for stepwise differentiation of mouse ESCs and iPSCs into bone-resorbing osteoclasts based upon a monoculture approach consisting of three steps. First, based on conventional hanging-drop methods, embryoid bodies (EBs) were produced from mouse ESCs or iPSCs. Second, EBs were cultured in medium supplemented with macrophage colony-stimulating factor (M-CSF), and differentiated to osteoclast precursors, which expressed CD11b. Finally, ESC- or iPSC-derived osteoclast precursors stimulated with receptor activator of nuclear factor-B ligand (RANKL) and M-CSF formed large multinucleated osteoclast-like cells that expressed tartrate-resistant acid phosphatase and were capable of bone resorption. Molecular analysis showed that the expression of osteoclast marker genes such as Nfatc1, Ctsk, and Acp5 are increased in a RANKL-dependent manner. Thus, our procedure is simple and easy and would be helpful for stem cell-based bone research.

  3. A sphingolipid-dependent diffusion barrier confines ER stress to the yeast mother cell

    Science.gov (United States)

    Clay, Lori; Caudron, Fabrice; Denoth-Lippuner, Annina; Boettcher, Barbara; Buvelot Frei, Stéphanie; Snapp, Erik Lee; Barral, Yves

    2014-01-01

    In many cell types, lateral diffusion barriers compartmentalize the plasma membrane and, at least in budding yeast, the endoplasmic reticulum (ER). However, the molecular nature of these barriers, their mode of action and their cellular functions are unclear. Here, we show that misfolded proteins of the ER remain confined into the mother compartment of budding yeast cells. Confinement required the formation of a lateral diffusion barrier in the form of a distinct domain of the ER-membrane at the bud neck, in a septin-, Bud1 GTPase- and sphingolipid-dependent manner. The sphingolipids, but not Bud1, also contributed to barrier formation in the outer membrane of the dividing nucleus. Barrier-dependent confinement of ER stress into the mother cell promoted aging. Together, our data clarify the physical nature of lateral diffusion barriers in the ER and establish the role of such barriers in the asymmetric segregation of proteotoxic misfolded proteins during cell division and aging. DOI: http://dx.doi.org/10.7554/eLife.01883.001 PMID:24843009

  4. PKM2 Thr454 phosphorylation increases its nuclear translocation and promotes xenograft tumor growth in A549 human lung cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhenhai, E-mail: tomsyu@163.com [Center for Reproductive Medicine, Affiliated Hospital of Weifang Medical University, Weifang, Shandong, 261031 (China); Huang, Liangqian [Institute of Health Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS) & Shanghai Jiao Tong University School of Medicine -SJTUSM, Shanghai, 200025 (China); Qiao, Pengyun; Jiang, Aifang; Wang, Li; Yang, Tingting [Center for Reproductive Medicine, Affiliated Hospital of Weifang Medical University, Weifang, Shandong, 261031 (China); Tang, Shengjian; Zhang, Wei [Plastic Surgery Institute of Weifang Medical University, Weifang, Shandong, 261041 (China); Ren, Chune, E-mail: ren@wfmc.edu.cn [Center for Reproductive Medicine, Affiliated Hospital of Weifang Medical University, Weifang, Shandong, 261031 (China)

    2016-05-13

    Pyruvate kinase M2 (PKM2) is a key enzyme of glycolysis which is highly expressed in many tumor cells, and plays an important role in the Warburg effect. In previous study, we found PIM2 phosphorylates PKM2 at Thr454 residue (Yu, etl 2013). However, the functions of PKM2 Thr454 modification in cancer cells still remain unclear. Here we find PKM2 translocates into the nucleus after Thr454 phosphorylation. Replacement of wild type PKM2 with a mutant (T454A) enhances mitochondrial respiration, decreases pentose phosphate pathway, and enhances chemosensitivity in A549 cells. In addition, the mutant (T454A) PKM2 reduces xenograft tumor growth in nude mice. These findings demonstrate that PKM2 T454 phosphorylation is a potential therapeutic target in lung cancer.

  5. By the numbers: Structure-seeking individuals prefer quantitative over qualitative representations of personal value to compensate for the threat of unclear performance contingencies.

    Science.gov (United States)

    Rothschild, Zachary K; Landau, Mark J; Sullivan, Daniel

    2011-11-01

    What combination of dispositional and situational factors leads people to represent their personal value in quantitative terms (e.g., salary) rather than qualitative terms (e.g., virtue)? Integrating research on quantitative information seeking, dispositional epistemic motivation, and learned helplessness, the current article hypothesized that individuals high, but not low, in uncertainty avoidance (measured with the Personal Need for Structure Scale [PNS]) would prefer quantitative (over qualitative) value representations to compensate for the diminished self-esteem certainty caused by exposure to unclear performance contingencies. Accordingly, in Study 1 high-PNS participants exposed to unclear (vs. clear) performance contingencies in one domain (visual intelligence) preferred a quantitative value representation in another domain (verbal intelligence). Study 2 showed that this effect is mediated by self-esteem certainty, not self-esteem level. Study 3 included a failure feedback condition to further isolate the role of epistemic motivation, as distinct from self-enhancement motivation, in driving the tendency to quantify personal value.

  6. 3-Deazaneplanocin A suppresses aggressive phenotype-related gene expression in an oral squamous cell carcinoma cell line

    International Nuclear Information System (INIS)

    Hatta, Mitsutoki; Naganuma, Kaori; Kato, Kenichi; Yamazaki, Jun

    2015-01-01

    In tumor tissues, alterations of gene expression caused by aberrant epigenetic modifications confer phenotypic diversity on malignant cells. Although 3-deazaneplanocin A (DZNep) has been shown to reactivate tumor suppressor genes in several cancer cells, it remains unclear whether DZNep attenuates the malignant phenotypes of oral squamous cell carcinoma (OSCC) cells. In this study, we investigated the effect of DZNep on the expression of genes related to aggressive phenotypes, such as epithelial–mesenchymal transition, in OSCC cells. We found that DZNep reduced the cellular levels of polycomb group proteins (EZH2, SUZ12, BMI1, and RING1A) and the associated trimethylation of Lys27 on histone H3 and monoubiquitination of Lys119 on histone H2A in the poorly differentiated OSCC cell line SAS. Immunocytochemical staining demonstrated that DZNep induced the reorganization of filamentous actin and the membrane localization of E-cadherin associated with cell–cell adhesions. We also found an inhibitory effect of DZNep on cell proliferation using a WST assay. Finally, quantitative RT-PCR analysis demonstrated that genes involved in the aggressive phenotypes (TWIST2, EGFR, ACTA2, TGFB1, WNT5B, and APLIN) were down-regulated, whereas epithelial phenotype genes (CDH1, CLDN4, IVL, and TGM1) were up-regulated in SAS cells treated with DZNep. Collectively, our findings suggest that DZNep reverses the aggressive characteristics of OSCC cells through the dynamic regulation of epithelial plasticity via the reprogramming of gene expression patterns. - Highlights: • DZNep reduced PcG proteins and associated histone modifications in OSCC cells. • DZNep enhanced cell–cell adhesion indicative of epithelial phenotype in OSCC cells. • DZNep suppressed the aggressive phenotype-related gene expression in OSCC cells. • DZNep activated the gene expression of epithelial markers in OSCC cells.

  7. 3-Deazaneplanocin A suppresses aggressive phenotype-related gene expression in an oral squamous cell carcinoma cell line

    Energy Technology Data Exchange (ETDEWEB)

    Hatta, Mitsutoki, E-mail: hatta@college.fdcnet.ac.jp [Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka (Japan); Naganuma, Kaori [Department of Oral and Maxillofacial Surgery, Fukuoka Dental College, Fukuoka (Japan); Kato, Kenichi; Yamazaki, Jun [Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka (Japan)

    2015-12-04

    In tumor tissues, alterations of gene expression caused by aberrant epigenetic modifications confer phenotypic diversity on malignant cells. Although 3-deazaneplanocin A (DZNep) has been shown to reactivate tumor suppressor genes in several cancer cells, it remains unclear whether DZNep attenuates the malignant phenotypes of oral squamous cell carcinoma (OSCC) cells. In this study, we investigated the effect of DZNep on the expression of genes related to aggressive phenotypes, such as epithelial–mesenchymal transition, in OSCC cells. We found that DZNep reduced the cellular levels of polycomb group proteins (EZH2, SUZ12, BMI1, and RING1A) and the associated trimethylation of Lys27 on histone H3 and monoubiquitination of Lys119 on histone H2A in the poorly differentiated OSCC cell line SAS. Immunocytochemical staining demonstrated that DZNep induced the reorganization of filamentous actin and the membrane localization of E-cadherin associated with cell–cell adhesions. We also found an inhibitory effect of DZNep on cell proliferation using a WST assay. Finally, quantitative RT-PCR analysis demonstrated that genes involved in the aggressive phenotypes (TWIST2, EGFR, ACTA2, TGFB1, WNT5B, and APLIN) were down-regulated, whereas epithelial phenotype genes (CDH1, CLDN4, IVL, and TGM1) were up-regulated in SAS cells treated with DZNep. Collectively, our findings suggest that DZNep reverses the aggressive characteristics of OSCC cells through the dynamic regulation of epithelial plasticity via the reprogramming of gene expression patterns. - Highlights: • DZNep reduced PcG proteins and associated histone modifications in OSCC cells. • DZNep enhanced cell–cell adhesion indicative of epithelial phenotype in OSCC cells. • DZNep suppressed the aggressive phenotype-related gene expression in OSCC cells. • DZNep activated the gene expression of epithelial markers in OSCC cells.

  8. Protective effects of red wine flavonols on 4-hydroxynonenal-induced apoptosis in PC12 cells.

    Science.gov (United States)

    Jang, Young Jin; Kang, Nam Joo; Lee, Ki Won; Lee, Hyong Joo

    2009-08-01

    There is accumulating evidence that a moderate consumption of red wine has health benefits, such as the inhibition of neurodegenerative diseases. Although this is generally attributed to resveratrol, the protective mechanisms and the active substance(s) remain unclear. We examined whether and how red wine extract (RWE) and red wine flavonols quercetin and myricetin inhibited 4-hydroxynonenal (HNE)-induced apoptosis of rat pheochromocytoma PC12 cells. RWE attenuated HNE-induced PC12 cell death in a dose-dependent manner. HNE induced cleavage of poly(ADP-ribose) polymerase, which is involved in DNA repair in the nucleus, and this was inhibited by RWE treatment. Treatment with RWE also inhibited HNE-induced nuclear condensation in PC12 cells. Data of 2',7'-dichlorofluorescin diacetate showed that RWE protected against apoptosis of PC12 cells by attenuating intracellular reactive oxygen species. The cytoprotective effects on HNE-induced cell death were stronger for quercetin and myricetin than for resveratrol. HNE-induced nuclear condensation was attenuated by quercetin and myricetin. These results suggest that the neuroprotective potential of red wine is attributable to flavonols rather than to resveratrol.

  9. Pneumococcal Competence Coordination Relies on a Cell-Contact Sensing Mechanism.

    Directory of Open Access Journals (Sweden)

    Marc Prudhomme

    2016-06-01

    Full Text Available Bacteria have evolved various inducible genetic programs to face many types of stress that challenge their growth and survival. Competence is one such program. It enables genetic transformation, a major horizontal gene transfer process. Competence development in liquid cultures of Streptococcus pneumoniae is synchronized within the whole cell population. This collective behavior is known to depend on an exported signaling Competence Stimulating Peptide (CSP, whose action generates a positive feedback loop. However, it is unclear how this CSP-dependent population switch is coordinated. By monitoring spontaneous competence development in real time during growth of four distinct pneumococcal lineages, we have found that competence shift in the population relies on a self-activated cell fraction that arises via a growth time-dependent mechanism. We demonstrate that CSP remains bound to cells during this event, and conclude that the rate of competence development corresponds to the propagation of competence by contact between activated and quiescent cells. We validated this two-step cell-contact sensing mechanism by measuring competence development during co-cultivation of strains with altered capacity to produce or respond to CSP. Finally, we found that the membrane protein ComD retains the CSP, limiting its free diffusion in the medium. We propose that competence initiator cells originate stochastically in response to stress, to form a distinct subpopulation that then transmits the CSP by cell-cell contact.

  10. Pluripotency transcription factors and Tet1/2 maintain Brd4-independent stem cell identity.

    Science.gov (United States)

    Finley, Lydia W S; Vardhana, Santosha A; Carey, Bryce W; Alonso-Curbelo, Direna; Koche, Richard; Chen, Yanyang; Wen, Duancheng; King, Bryan; Radler, Megan R; Rafii, Shahin; Lowe, Scott W; Allis, C David; Thompson, Craig B

    2018-05-01

    A robust network of transcription factors and an open chromatin landscape are hallmarks of the naive pluripotent state. Recently, the acetyllysine reader Brd4 has been implicated in stem cell maintenance, but the relative contribution of Brd4 to pluripotency remains unclear. Here, we show that Brd4 is dispensable for self-renewal and pluripotency of embryonic stem cells (ESCs). When maintained in their ground state, ESCs retain transcription factor binding and chromatin accessibility independent of Brd4 function or expression. In metastable ESCs, Brd4 independence can be achieved by increased expression of pluripotency transcription factors, including STAT3, Nanog or Klf4, so long as the DNA methylcytosine oxidases Tet1 and Tet2 are present. These data reveal that Brd4 is not essential for ESC self-renewal. Rather, the levels of pluripotency transcription factor abundance and Tet1/2 function determine the extent to which bromodomain recognition of protein acetylation contributes to the maintenance of gene expression and cell identity.

  11. Fluoxetine regulates cell growth inhibition of interferon-α.

    Science.gov (United States)

    Lin, Yu-Min; Yu, Bu-Chin; Chiu, Wen-Tai; Sun, Hung-Yu; Chien, Yu-Chieh; Su, Hui-Chen; Yen, Shu-Yang; Lai, Hsin-Wen; Bai, Chyi-Huey; Young, Kung-Chia; Tsao, Chiung-Wen

    2016-10-01

    Fluoxetine, a well-known anti-depression agent, may act as a chemosensitizer to assist and promote cancer therapy. However, how fluoxetine regulates cellular signaling to enhance cellular responses against tumor cell growth remains unclear. In the present study, addition of fluoxetine promoted growth inhibition of interferon-alpha (IFN-α) in human bladder carcinoma cells but not in normal uroepithelial cells through lessening the IFN-α-induced apoptosis but switching to cause G1 arrest, and maintaining the IFN-α-mediated reduction in G2/M phase. Activations and signal transducer and transactivator (STAT)-1 and peroxisome proliferator-activated receptor alpha (PPAR-α) were involved in this process. Chemical inhibitions of STAT-1 or PPAR-α partially rescued bladder carcinoma cells from IFN-α-mediated growth inhibition via blockades of G1 arrest, cyclin D1 reduction, p53 downregulation and p27 upregulation in the presence of fluoxetine. However, the functions of both proteins were not involved in the control of fluoxetine over apoptosis and maintained the declined G2/M phase of IFN-α. These results indicated that activation of PPAR-α and STAT-1 participated, at least in part, in growth inhibition of IFN-α in the presence of fluoxetine.

  12. Production of cloned mice and ES cells from adult somatic cells by nuclear transfer: how to improve cloning efficiency?

    Science.gov (United States)

    Wakayama, Teruhiko

    2007-02-01

    Although it has now been 10 years since the first cloned mammals were generated from somatic cells using nuclear transfer (NT), most cloned embryos usually undergo developmental arrest prior to or soon after implantation, and the success rate for producing live offspring by cloning remains below 5%. The low success rate is believed to be associated with epigenetic errors, including abnormal DNA hypermethylation, but the mechanism of "reprogramming" is unclear. We have been able to develop a stable NT method in the mouse in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. Especially in the mouse, only a few laboratories can make clones from adult somatic cells, and cloned mice are never successfully produced from most mouse strains. However, this technique promises to be an important tool for future research in basic biology. For example, NT can be used to generate embryonic stem (NT-ES) cell lines from a patient's own somatic cells. We have shown that NT-ES cells are equivalent to ES cells derived from fertilized embryos and that they can be generated relatively easily from a variety of mouse genotypes and cell types of both sexes, even though it may be more difficult to generate clones directly. In general, NT-ES cell techniques are expected to be applied to regenerative medicine; however, this technique can also be applied to the preservation of genetic resources of mouse strain instead of embryos, oocytes and spermatozoa. This review describes how to improve cloning efficiency and NT-ES cell establishment and further applications.

  13. Value of prophylactic antibiotics for invasive dental procedures unclear.

    Science.gov (United States)

    Rochlen, Glenn K; Keenan, Analia Veitz

    2014-03-01

    The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, the US National Institutes of Health Trials Register and the metaRegister of Controlled Trials. Randomised controlled trials (RCTs) and controlled clinical trials (CCTs) would be included where available. Due to the low incidence of bacterial endocarditis it was anticipated that few such trials would be found. Cohort and case-control studies were included where suitably matched control or comparison groups had been studied. Two review authors independently selected studies for inclusion then assessed risk of bias and extracted data from the included study. Only one case controlled study met the inclusion criteria. It collected all the cases of endocarditis in the Netherlands over two years, finding a total of 24 people who developed endocarditis within 180 days of an invasive dental procedure, definitely requiring prophylaxis according to current guidelines, and who were at increased risk of endocarditis due to a pre-existing cardiac problem. This study included participants who died because of the endocarditis (using proxies). Controls attended local cardiology outpatient clinics for similar cardiac problems, had undergone an invasive dental procedure within the past 180 days, and were matched by age with the cases. No significant effect of penicillin prophylaxis on the incidence of endocarditis could be seen. No data were found on other outcomes. There remains no evidence that antibiotic prophylaxis is either effective or ineffective against bacterial endocarditis in people considered at risk who are about to undergo an invasive dental procedure. It is not clear whether the potential harms and costs of penicillin administration outweigh any beneficial effect. Ethically, practitioners need to discuss the potential benefits and harms of antibiotic prophylaxis with their patients before a decision is made about administration.

  14. A Unique T-Cell Receptor Amino Acid Sequence Selected by Human T-Cell Lymphotropic Virus Type 1 Tax301-309-Specific Cytotoxic T Cells in HLA-A24:02-Positive Asymptomatic Carriers and Adult T-Cell Leukemia/Lymphoma Patients.

    Science.gov (United States)

    Ishihara, Yuko; Tanaka, Yukie; Kobayashi, Seiichiro; Kawamura, Koji; Nakasone, Hideki; Gomyo, Ayumi; Hayakawa, Jin; Tamaki, Masaharu; Akahoshi, Yu; Harada, Naonori; Kusuda, Machiko; Kameda, Kazuaki; Ugai, Tomotaka; Wada, Hidenori; Sakamoto, Kana; Sato, Miki; Terasako-Saito, Kiriko; Kikuchi, Misato; Kimura, Shun-Ichi; Tanihara, Aki; Kako, Shinichi; Uchimaru, Kaoru; Kanda, Yoshinobu

    2017-10-01

    We previously reported that the T-cell receptor (TCR) repertoire of human T-cell lymphotropic virus type 1 (HTLV-1) Tax 301-309 -specific CD8 + cytotoxic T cells (Tax 301-309 -CTLs) was highly restricted and a particular amino acid sequence motif, the PDR motif, was conserved among HLA-A*24:02-positive (HLA-A*24:02 + ) adult T-cell leukemia/lymphoma (ATL) patients who had undergone allogeneic hematopoietic cell transplantation (allo-HSCT). Furthermore, we found that donor-derived PDR + CTLs selectively expanded in ATL long-term HSCT survivors with strong CTL activity against HTLV-1. On the other hand, the TCR repertoires in Tax 301-309 -CTLs of asymptomatic HTLV-1 carriers (ACs) remain unclear. In this study, we directly identified the DNA sequence of complementarity-determining region 3 (CDR3) of the TCR-β chain of Tax 301-309 -CTLs at the single-cell level and compared not only the TCR repertoires but also the frequencies and phenotypes of Tax 301-309 -CTLs between ACs and ATL patients. We did not observe any essential difference in the frequencies of Tax 301-309 -CTLs between ACs and ATL patients. In the single-cell TCR repertoire analysis of Tax 301-309 -CTLs, 1,458 Tax 301-309 -CTLs and 140 clones were identified in this cohort. Tax 301-309 -CTLs showed highly restricted TCR repertoires with a strongly biased usage of BV7, and PDR, the unique motif in TCR-β CDR3, was exclusively observed in all ACs and ATL patients. However, there was no correlation between PDR + CTL frequencies and HTLV-1 proviral load (PVL). In conclusion, we have identified, for the first time, a unique amino acid sequence, PDR, as a public TCR-CDR3 motif against Tax in HLA-A*24:02 + HTLV-1-infected individuals. Further investigations are warranted to elucidate the role of the PDR + CTL response in the progression from carrier state to ATL. IMPORTANCE ATL is an aggressive T-cell malignancy caused by HTLV-1 infection. The HTLV-1 regulatory protein Tax aggressively promotes the

  15. Endogenous hepatitis C virus homolog fragments in European rabbit and hare genomes replicate in cell culture.

    Directory of Open Access Journals (Sweden)

    Eliane Silva

    Full Text Available Endogenous retroviruses, non-retroviral RNA viruses and DNA viruses have been found in the mammalian genomes. The origin of Hepatitis C virus (HCV, the major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma in humans, remains unclear since its discovery. Here we show that fragments homologous to HCV structural and non-structural (NS proteins present in the European rabbit (Oryctolagus cuniculus and hare (Lepus europaeus genomes replicate in bovine cell cultures. The HCV genomic homolog fragments were demonstrated by RT-PCR, PCR, mass spectrometry, and replication in bovine cell cultures by immunofluorescence assay (IFA and immunogold electron microscopy (IEM using specific MAbs for HCV NS3, NS4A, and NS5 proteins. These findings may lead to novel research approaches on the HCV origin, genesis, evolution and diversity.

  16. Intestinal Stem Cell Markers in the Intestinal Metaplasia of Stomach and Barrett's Esophagus.

    Directory of Open Access Journals (Sweden)

    Bo Gun Jang

    Full Text Available Gastric intestinal metaplasia (IM is a highly prevalent preneoplastic lesion; however, the molecular mechanisms regulating its development remain unclear. We have previously shown that a population of cells expressing the intestinal stem cell (ISC marker LGR5 increases remarkably in IM. In this study, we further investigated the molecular characteristics of these LGR5+ cells in IM by examining the expression profile of several ISC markers. Notably, we found that ISC markers-including OLFM4 and EPHB2-are positively associated with the CDX2 expression in non-tumorous gastric tissues. This finding was confirmed in stomach lesions with or without metaplasia, which demonstrated that OLFM4 and EPHB2 expression gradually increased with metaplastic progression. Moreover, RNA in situ hybridization revealed that LGR5+ cells coexpress several ISC markers and remained confined to the base of metaplastic glands, reminiscent to that of normal intestinal crypts, whereas those in normal antral glands expressed none of these markers. Furthermore, a large number of ISC marker-expressing cells were diffusely distributed in gastric adenomas, suggesting that these markers may facilitate gastric tumorigenesis. In addition, Barrett's esophagus (BE-which is histologically similar to intestinal metaplasia-exhibited a similar distribution of ISC markers, indicating the presence of a stem cell population with intestinal differentiation potential. In conclusion, we identified that LGR5+ cells in gastric IM and BE coexpress ISC markers, and exhibit the same expression profile as those found in normal intestinal crypts. Taken together, these results implicate an intestinal-like stem cell population in the pathogenesis of IM, and provide an important basis for understanding the development and maintenance of this disease.

  17. Cooperation between Monocyte-Derived Cells and Lymphoid Cells in the Acute Response to a Bacterial Lung Pathogen.

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    Andrew S Brown

    2016-06-01

    Full Text Available Legionella pneumophila is the causative agent of Legionnaires' disease, a potentially fatal lung infection. Alveolar macrophages support intracellular replication of L. pneumophila, however the contributions of other immune cell types to bacterial killing during infection are unclear. Here, we used recently described methods to characterise the major inflammatory cells in lung after acute respiratory infection of mice with L. pneumophila. We observed that the numbers of alveolar macrophages rapidly decreased after infection coincident with a rapid infiltration of the lung by monocyte-derived cells (MC, which, together with neutrophils, became the dominant inflammatory cells associated with the bacteria. Using mice in which the ability of MC to infiltrate tissues is impaired it was found that MC were required for bacterial clearance and were the major source of IL12. IL12 was needed to induce IFNγ production by lymphoid cells including NK cells, memory T cells, NKT cells and γδ T cells. Memory T cells that produced IFNγ appeared to be circulating effector/memory T cells that infiltrated the lung after infection. IFNγ production by memory T cells was stimulated in an antigen-independent fashion and could effectively clear bacteria from the lung indicating that memory T cells are an important contributor to innate bacterial defence. We also determined that a major function of IFNγ was to stimulate bactericidal activity of MC. On the other hand, neutrophils did not require IFNγ to kill bacteria and alveolar macrophages remained poorly bactericidal even in the presence of IFNγ. This work has revealed a cooperative innate immune circuit between lymphoid cells and MC that combats acute L. pneumophila infection and defines a specific role for IFNγ in anti-bacterial immunity.

  18. Role of T-bet, the master regulator of Th1 cells, in the cytotoxicity of murine CD4+ T cells.

    Science.gov (United States)

    Eshima, Koji; Misawa, Kana; Ohashi, Chihiro; Iwabuchi, Kazuya

    2018-05-01

    Although CD4 + T cells are generally regarded as helper T cells, some activated CD4 + T cells have cytotoxic properties. Given that CD4 + cytotoxic T lymphocytes (CTLs) often secrete IFN-γ, CTL activity among CD4 + T cells may be attributable to Th1 cells, where a T-box family molecule, T-bet serves as the "master regulator". However, although the essential contribution of T-bet to expression of IFN-γ has been well-documented, it remains unclear whether T-bet is involved in CD4 + T cell-mediated cytotoxicity. In this study, to investigate the ability of T-bet to confer cytolytic activity on CD4 + T cells, the T-bet gene (Tbx21) was introduced into non-cytocidal CD4 + T cell lines and their cytolytic function analyzed. Up-regulation of FasL (CD178), which provided the transfectant with cytotoxicity, was observed in Tbx21transfected CD4 + T cells but not in untransfected parental cells. In one cell line, T-bet transduction also induced perforin gene (Prf1) expression and Tbx21 transfectants efficiently killed Fas - target cells. Although T-bet was found to repress up-regulation of CD40L (CD154), which controls FasL-mediated cytolysis, the extent of CD40L up-regulation on in vitro-differentiated Th1 cells was similar to that on Th2 cells, suggesting the existence of a compensatory mechanism. These results collectively indicate that T-bet may be involved in the expression of genes, such as FasL and Prf1, which confer cytotoxicity on Th1 cells. © 2018 The Societies and John Wiley & Sons Australia, Ltd.

  19. Influences of lamin A levels on induction of pluripotent stem cells

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    Bingfeng Zuo

    2012-09-01

    Lamin A is an inner nuclear membrane protein that maintains nuclear structure integrity, is involved in transcription, DNA damage response and genomic stability, and also links to cell differentiation, senescence, premature aging and associated diseases. Induced pluripotent stem (iPS cells have been successfully generated from various types of cells and used to model human diseases. It remains unclear whether levels of lamin A influence reprogramming of somatic cells to pluripotent states during iPS induction. Consistently, lamin A is expressed more in differentiated than in relatively undifferentiated somatic cells, and increases in expression levels with age. Somatic cells with various expression levels of lamin A differ in their dynamics and efficiency during iPS cell induction. Cells with higher levels of lamin A show slower reprogramming and decreased efficiency to iPS cells. Furthermore, depletion of lamin A by transient shRNA accelerates iPS cell induction from fibroblasts. Reduced levels of lamin A are associated with increased expression of pluripotent genes Oct4 and Nanog, and telomerase genes Tert and Terc. On the contrary, overexpression of lamin A retards somatic cell reprogramming to iPS-like colony formation. Our data suggest that levels of lamin A influence reprogramming of somatic cells to pluripotent stem cells and that artificial silencing of lamin A facilitates iPS cell induction. These findings may have implications in enhancing rejuvenation of senescent or older cells by iPS technology and manipulating lamin A levels.

  20. CAR T Cells in Trials: Recent Achievements and Challenges that Remain in the Production of Modified T Cells for Clinical Applications.

    Science.gov (United States)

    Köhl, Ulrike; Arsenieva, Stanislava; Holzinger, Astrid; Abken, Hinrich

    2018-04-05

    The adoptive transfer of chimeric antigen receptor (CAR)-modified T cells is attracting growing interest for the treatment of malignant diseases. Early trials with anti-CD19 CAR T cells have achieved spectacular remissions in B-cell leukemia and lymphoma, so far refractory, very recently resulting in the Food and Drug Administration approval of CD19 CAR T cells for therapy. With further applications and increasing numbers of patients, the reproducible manufacture of high-quality clinical-grade CAR T cells is becoming an ever greater challenge. New processing techniques, quality-control mechanisms, and logistic developments are required to meet both medical needs and regulatory restrictions. This paper summarizes the state-of-the-art in manufacturing CAR T cells and the current challenges that need to be overcome to implement this type of cell therapy in the treatment of a variety of malignant diseases and in a greater number of patients.

  1. Lineage-Restricted Mammary Stem Cells Sustain the Development, Homeostasis, and Regeneration of the Estrogen Receptor Positive Lineage.

    Science.gov (United States)

    Van Keymeulen, Alexandra; Fioramonti, Marco; Centonze, Alessia; Bouvencourt, Gaëlle; Achouri, Younes; Blanpain, Cédric

    2017-08-15

    The mammary gland (MG) is composed of different cell lineages, including the basal and the luminal cells (LCs) that are maintained by distinct stem cell (SC) populations. LCs can be subdivided into estrogen receptor (ER) + and ER - cells. LCs act as the cancer cell of origin in different types of mammary tumors. It remains unclear whether the heterogeneity found in luminal-derived mammary tumors arises from a pre-existing heterogeneity within LCs. To investigate LC heterogeneity, we used lineage tracing to assess whether the ER + lineage is maintained by multipotent SCs or by lineage-restricted SCs. To this end, we generated doxycycline-inducible ER-rtTA mice that allowed us to perform genetic lineage tracing of ER + LCs and study their fate and long-term maintenance. Our results show that ER + cells are maintained by lineage-restricted SCs that exclusively contribute to the expansion of the ER + lineage during puberty and their maintenance during adult life. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  2. Tonic 4-1BB Costimulation in Chimeric Antigen Receptors Impedes T Cell Survival and Is Vector-Dependent

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    Diogo Gomes-Silva

    2017-10-01

    Full Text Available Antigen-independent tonic signaling by chimeric antigen receptors (CARs can increase differentiation and exhaustion of T cells, limiting their potency. Incorporating 4-1BB costimulation in CARs may enable T cells to resist this functional exhaustion; however, the potential ramifications of tonic 4-1BB signaling in CAR T cells remain unclear. Here, we found that tonic CAR-derived 4-1BB signaling can produce toxicity in T cells via continuous TRAF2-dependent activation of the nuclear factor κB (NF-κB pathway and augmented FAS-dependent cell death. This mechanism was amplified in a non-self-inactivating gammaretroviral vector through positive feedback on the long terminal repeat (LTR promoter, further enhancing CAR expression and tonic signaling. Attenuating CAR expression by substitution with a self-inactivating lentiviral vector minimized tonic signaling and improved T cell expansion and anti-tumor function. These studies illuminate the interaction between tonic CAR signaling and the chosen expression platform and identify inhibitory properties of the 4-1BB costimulatory domain that have direct implications for rational CAR design.

  3. Fisetin suppresses malignant proliferation in human oral squamous cell carcinoma through inhibition of Met/Src signaling pathways.

    Science.gov (United States)

    Li, Yan-Shu; Qin, Xing-Jun; Dai, Wei

    2017-01-01

    Fisetin (3,7,3',4'-tetrahydroxyflavone) is a dietary flavonoid and has been indicated as a novel anti-cancer agent in several types of cancer cells. However, the mechanisms underlying the effect of fisetin in human oral squamous cell carcinoma (OSCC) remain unclear. Here, we report that fisetin significantly inhibits tumor cell proliferation and induces apoptosis in OSCC (UM-SCC-23 and Tca-8113) cancer cell lines. Further analysis demonstrates that fisetin also inhibits Met/Src signaling pathways using the PathScan ® receptor tyrosine kinases (RTK) Signaling Antibody Array Kit. Fisetin resulted in decreased basal expression of Met and Src protein in UM-SCC-23 cancer cell lines, which validated by western blot. A student's t -test (two-tailed) was used to compare differences between groups. Furthermore, fisetin significantly inhibited the expression of a disintegrin and metalloproteinase 9 (ADAM9) protein in OSCC cells. Taken together, these results provide novel insights into the mechanism of fisetin and suggest potential therapeutic strategies for human OSCC by blocking the Met/Src signaling pathways.

  4. Cell Adhesion Molecule CD166/ALCAM Functions Within the Crypt to Orchestrate Murine Intestinal Stem Cell HomeostasisSummary

    Directory of Open Access Journals (Sweden)

    Nicholas R. Smith

    2017-05-01

    Full Text Available Background & Aims: Intestinal epithelial homeostasis is maintained by active-cycling and slow-cycling stem cells confined within an instructive crypt-based niche. Exquisite regulating of these stem cell populations along the proliferation-to-differentiation axis maintains a homeostatic balance to prevent hyperproliferation and cancer. Although recent studies focus on how secreted ligands from mesenchymal and epithelial populations regulate intestinal stem cells (ISCs, it remains unclear what role cell adhesion plays in shaping the regulatory niche. Previously we have shown that the cell adhesion molecule and cancer stem cell marker, CD166/ALCAM (activated leukocyte cell adhesion molecule, is highly expressed by both active-cycling Lgr5+ ISCs and adjacent Paneth cells within the crypt base, supporting the hypothesis that CD166 functions to mediate ISC maintenance and signal coordination. Methods: Here we tested this hypothesis by analyzing a CD166–/– mouse combined with immunohistochemical, flow cytometry, gene expression, and enteroid culture. Results: We found that animals lacking CD166 expression harbored fewer active-cycling Lgr5+ ISCs. Homeostasis was maintained by expansion of the transit-amplifying compartment and not by slow-cycling Bmi1+ ISC stimulation. Loss of active-cycling ISCs was coupled with deregulated Paneth cell homeostasis, manifested as increased numbers of immature Paneth progenitors due to decreased terminal differentiation, linked to defective Wnt signaling. CD166–/– Paneth cells expressed reduced Wnt3 ligand expression and depleted nuclear β-catenin. Conclusions: These data support a function for CD166 as an important cell adhesion molecule that shapes the signaling microenvironment by mediating ISC–niche cell interactions. Furthermore, loss of CD166 expression results in decreased ISC and Paneth cell homeostasis and an altered Wnt microenvironment. Keywords: Intestinal Stem Cell, Homeostasis

  5. Nano-Scaled Particles of Titanium Dioxide Convert Benign Mouse Fibrosarcoma Cells into Aggressive Tumor Cells

    Science.gov (United States)

    Onuma, Kunishige; Sato, Yu; Ogawara, Satomi; Shirasawa, Nobuyuki; Kobayashi, Masanobu; Yoshitake, Jun; Yoshimura, Tetsuhiko; Iigo, Masaaki; Fujii, Junichi; Okada, Futoshi

    2009-01-01

    Nanoparticles are prevalent in both commercial and medicinal products; however, the contribution of nanomaterials to carcinogenesis remains unclear. We therefore examined the effects of nano-sized titanium dioxide (TiO2) on poorly tumorigenic and nonmetastatic QR-32 fibrosarcoma cells. We found that mice that were cotransplanted subcutaneously with QR-32 cells and nano-sized TiO2, either uncoated (TiO2−1, hydrophilic) or coated with stearic acid (TiO2−2, hydrophobic), did not form tumors. However, QR-32 cells became tumorigenic after injection into sites previously implanted with TiO2−1, but not TiO2−2, and these developing tumors acquired metastatic phenotypes. No differences were observed either histologically or in inflammatory cytokine mRNA expression between TiO2−1 and TiO2−2 treatments. However, TiO2−2, but not TiO2−1, generated high levels of reactive oxygen species (ROS) in cell-free conditions. Although both TiO2−1 and TiO2−2 resulted in intracellular ROS formation, TiO2−2 elicited a stronger response, resulting in cytotoxicity to the QR-32 cells. Moreover, TiO2−2, but not TiO2−1, led to the development of nuclear interstices and multinucleate cells. Cells that survived the TiO2 toxicity acquired a tumorigenic phenotype. TiO2-induced ROS formation and its related cell injury were inhibited by the addition of antioxidant N-acetyl-l-cysteine. These results indicate that nano-sized TiO2 has the potential to convert benign tumor cells into malignant ones through the generation of ROS in the target cells. PMID:19815711

  6. Exosomes mediate hepatitis B virus (HBV) transmission and NK-cell dysfunction

    Science.gov (United States)

    Yang, Yinli; Han, Qiuju; Hou, Zhaohua; Zhang, Cai; Tian, Zhigang; Zhang, Jian

    2017-01-01

    Evidence suggests that exosomes can transfer genetic material between cells. However, their roles in hepatitis B virus (HBV) infection remain unclear. Here, we report that exosomes present in the sera of chronic hepatitis B (CHB) patients contained both HBV nucleic acids and HBV proteins, and transferred HBV to hepatocytes in an active manner. Notably, HBV nucleic acids were detected in natural killer (NK) cells from both CHB patients and healthy donors after exposure to HBV-positive exosomes. Through real-time fluorescence microscopy and flow cytometry, 1,1'-dioctadecyl-3,3,3',3',-tetramethylindodicarbocyanine, 4-chlorobenzenesulfnate salt (DiD)-labeled exosomes were observed to interact with NK cells and to be taken up by NK cells, which was enhanced by transforming growth factor-β treatment. Furthermore, HBV-positive exosomes impaired NK-cell functions, including interferon (IFN)-γ production, cytolytic activity, NK-cell proliferation and survival, as well as the responsiveness of the cells to poly (I:C) stimulation. HBV infection suppressed the expression of pattern-recognition receptors, especially retinoic acid inducible gene I (RIG-I), on NK cells, resulting in the dampening of the nuclear factor κB(NF-κB) and p38 mitogen-activated protein kinase pathways. Our results highlight a previously unappreciated role of exosomes in HBV transmission and NK-cell dysfunction during CHB infection. PMID:27238466

  7. Overexpressed CacyBP/SIP leads to the suppression of growth in renal cell carcinoma

    International Nuclear Information System (INIS)

    Sun, Shiren; Ning, Xiaoxuan; Liu, Jie; Liu, Lili; Chen, Yu; Han, Shuang; Zhang, Yanqi; Liang, Jie; Wu, Kaichun; Fan, Daiming

    2007-01-01

    Calcyclin-binding protein/Siah-1-interacting protein (CacyBP/SIP), a target protein of S100, has been identified as a component of a novel ubiquitinylation complex leading to β-catenin degradation, which was found to be related to the malignant phenotypes of gastric cancer. However, the roles of CacyBP/SIP in renal cell carcinoma still remain unclear. In the present study, we had analyzed the expression of the CacyBP/SIP protein in human renal cancer cells and clinical tissue samples. The possible roles of CacyBP/SIP in regulating the malignant phenotype of renal cancer cells were also investigated. The results demonstrated that the expression of CacyBP/SIP was markedly down-regulated in renal cell carcinoma tissues and cell lines. Ectopic overexpression of CacyBP/SIP in A498 cells inhibited the proliferation of this cell and delayed cell cycle progression significantly, which might be related to the down-regulation of Cyclin D1 through reducing β-catenin protein. CacyBP/SIP also suppressed colony formation in soft agar and its tumorigenicity in nude mice. Taken together, our work showed that CacyBP/SIP, as a novel down-regulated gene in renal cell carcinoma, suppressed proliferation and tumorigenesis of renal cancer cells

  8. Evaluation of Stem Cell-Derived Red Blood Cells as a Transfusion Product Using a Novel Animal Model.

    Science.gov (United States)

    Shah, Sandeep N; Gelderman, Monique P; Lewis, Emily M A; Farrel, John; Wood, Francine; Strader, Michael Brad; Alayash, Abdu I; Vostal, Jaroslav G

    2016-01-01

    Reliance on volunteer blood donors can lead to transfusion product shortages, and current liquid storage of red blood cells (RBCs) is associated with biochemical changes over time, known as 'the storage lesion'. Thus, there is a need for alternative sources of transfusable RBCs to supplement conventional blood donations. Extracorporeal production of stem cell-derived RBCs (stemRBCs) is a potential and yet untapped source of fresh, transfusable RBCs. A number of groups have attempted RBC differentiation from CD34+ cells. However, it is still unclear whether these stemRBCs could eventually be effective substitutes for traditional RBCs due to potential differences in oxygen carrying capacity, viability, deformability, and other critical parameters. We have generated ex vivo stemRBCs from primary human cord blood CD34+ cells and compared them to donor-derived RBCs based on a number of in vitro parameters. In vivo, we assessed stemRBC circulation kinetics in an animal model of transfusion and oxygen delivery in a mouse model of exercise performance. Our novel, chronically anemic, SCID mouse model can evaluate the potential of stemRBCs to deliver oxygen to tissues (muscle) under resting and exercise-induced hypoxic conditions. Based on our data, stem cell-derived RBCs have a similar biochemical profile compared to donor-derived RBCs. While certain key differences remain between donor-derived RBCs and stemRBCs, the ability of stemRBCs to deliver oxygen in a living organism provides support for further development as a transfusion product.

  9. Evaluation of Stem Cell-Derived Red Blood Cells as a Transfusion Product Using a Novel Animal Model.

    Directory of Open Access Journals (Sweden)

    Sandeep N Shah

    Full Text Available Reliance on volunteer blood donors can lead to transfusion product shortages, and current liquid storage of red blood cells (RBCs is associated with biochemical changes over time, known as 'the storage lesion'. Thus, there is a need for alternative sources of transfusable RBCs to supplement conventional blood donations. Extracorporeal production of stem cell-derived RBCs (stemRBCs is a potential and yet untapped source of fresh, transfusable RBCs. A number of groups have attempted RBC differentiation from CD34+ cells. However, it is still unclear whether these stemRBCs could eventually be effective substitutes for traditional RBCs due to potential differences in oxygen carrying capacity, viability, deformability, and other critical parameters. We have generated ex vivo stemRBCs from primary human cord blood CD34+ cells and compared them to donor-derived RBCs based on a number of in vitro parameters. In vivo, we assessed stemRBC circulation kinetics in an animal model of transfusion and oxygen delivery in a mouse model of exercise performance. Our novel, chronically anemic, SCID mouse model can evaluate the potential of stemRBCs to deliver oxygen to tissues (muscle under resting and exercise-induced hypoxic conditions. Based on our data, stem cell-derived RBCs have a similar biochemical profile compared to donor-derived RBCs. While certain key differences remain between donor-derived RBCs and stemRBCs, the ability of stemRBCs to deliver oxygen in a living organism provides support for further development as a transfusion product.

  10. Cells deficient in PARP-1 show an accelerated accumulation of DNA single strand breaks, but not AP sites, over the PARP-1-proficient cells exposed to MMS.

    Science.gov (United States)

    Pachkowski, Brian F; Tano, Keizo; Afonin, Valeriy; Elder, Rhoderick H; Takeda, Shunichi; Watanabe, Masami; Swenberg, James A; Nakamura, Jun

    2009-12-01

    Poly(ADP-ribose) polymerase-1 (PARP-1) is a base excision repair (BER) protein that binds to DNA single strand breaks (SSBs) and subsequently synthesizes and transfers poly(ADP-ribose) polymers to various nuclear proteins. Numerous biochemical studies have implicated PARP-1 as a modulator of BER; however, the role of PARP-1 in BER in living cells remains unclear partly due to lack of accurate quantitation of BER intermediates existing in cells. Since DT40 cells, chicken B lymphocytes, naturally lack PARP-2, DT40 cells allow for the investigation of the PARP-1 null phenotype without confounding by PARP-2. To test the hypothesis that PARP-1 is necessary for efficient BER during methylmethane sulfonate (MMS) exposure in vertebrate cells, intact DT40 cells and their isogenic PARP-1 null counterparts were challenged with different exposure scenarios for phenotypic characterization. With chronic exposure, PARP-1 null cells exhibited sensitivity to MMS but with an acute exposure did not accumulate base lesions or AP sites to a greater extent than wild-type cells. However, an increase in SSB content in PARP-1 null cell DNA, as indicated by glyoxal gel electrophoresis under neutral conditions, suggested the presence of BER intermediates. These data suggest that during exposure, PARP-1 impacts the stage of BER after excision of the deoxyribosephosphate moiety from the 5' end of DNA strand breaks by polymerase beta.

  11. Do migrating cells need a nucleus?

    Science.gov (United States)

    Hawkins, Rhoda J

    2018-03-05

    How the nucleus affects cell polarity and migration is unclear. In this issue, Graham et al. (2018. J. Cell Biol. https://doi.org/10.1083/jcb.201706097) show that enucleated cells polarize and migrate in two but not three dimensions and propose that the nucleus is a necessary component of the molecular clutch regulating normal mechanical responses. © 2018 Hawkins.

  12. «Unclear Enemy»: Why the Guerrilla War in France in 1814 Failed

    Directory of Open Access Journals (Sweden)

    Nikolay A. Mogilevskiy

    2015-01-01

    Full Text Available Abstract: Author of the article analyzes the reasons of the fail of Napoleon’s attempts to set the guerrilla war in France during the campaign of 1814. While the forces of anti-Napoleonic coalition were standing near the border of France, Napoleon did his best to recruit his new army. But the human resources of France were exhausted, and that’s why Napoleon decided to set the guerrillia. But all his proclamations and even his orders were disobeyed - French people were too tired of incessant war, and Napoleon again decided to gain his goals on the battlefield. Besides author shows great efforts of Russian headquarters to avoid the guerrilla war. Alexander I and his allies in theirs proclamations declared that they were fighting only with Napoleon, but not with the French nation. That tactic gave a brilliant result and helped to avoid the patriotic uplift in France in 1814. In this propagandistic war Napoleon was defeated and that cost him his throne. The reasons of Napoleon’s fail, firstly, was the unclear image of the enemy. French emperor didn’t manage to unite French nation against the rival. On the contrary the French Emperor, his enemies managed (in their proclamations and personal conversations to persuade the French people, that the allies had one enemy - the Emperor Napoleon, not the French nation, and the ultimate goal of war - to set peace on the European continent. That was exactly how the allies did set the disunity between Napoleon and his people. Ultimately, the combination of these factors was the reason that a guerrilla war never broke out in France.

  13. Analysis of miRNA expression profiles in melatonin-exposed GC-1 spg cell line.

    Science.gov (United States)

    Zhu, Xiaoling; Chen, Shuxiong; Jiang, Yanwen; Xu, Ying; Zhao, Yun; Chen, Lu; Li, Chunjin; Zhou, Xu

    2018-02-05

    Melatonin is an endocrine neurohormone secreted by pinealocytes in the pineal gland. It exerts diverse physiological effects, such as circadian rhythm regulator and antioxidant. However, the functional importance of melatonin in spermatogenesis regulation remains unclear. The objectives of this study are to: (1) detect melatonin affection on miRNA expression profiles in GC-1 spg cells by miRNA deep sequencing (DeepSeq) and (2) define melatonin affected miRNA-mRNA interactions and associated biological processes using bioinformatics analysis. GC-1 spg cells were cultured with melatonin (10 -7 M) for 24h. DeepSeq data were validated using quantitative real-time reverse transcription polymerase chain reaction analysis (qRT-PCR). A total of 176 miRNA expressions were found to be significantly different between two groups (fold change of >2 or melatonin could regulate the expression of miRNA to perform its physiological effects in GC-1 spg cells. These results should be useful to investigate the biological function of miRNAs regulated by melatonin in spermatogenesis and testicular germ cell tumor. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. T Cell Intrinsic USP15 Deficiency Promotes Excessive IFN-γ Production and an Immunosuppressive Tumor Microenvironment in MCA-Induced Fibrosarcoma

    Directory of Open Access Journals (Sweden)

    Qiang Zou

    2015-12-01

    Full Text Available USP15 is a deubiquitinase that negatively regulates activation of naive CD4+ T cells and generation of IFN-γ-producing T helper 1 (Th1 cells. USP15 deficiency in mice promotes antitumor T cell responses in a transplantable cancer model; however, it has remained unclear how deregulated T cell activation impacts primary tumor development during the prolonged interplay between tumors and the immune system. Here, we find that the USP15-deficient mice are hypersensitive to methylcholantrene (MCA-induced fibrosarcomas. Excessive IFN-γ production in USP15-deficient mice promotes expression of the immunosuppressive molecule PD-L1 and the chemokine CXCL12, causing accumulation of T-bet+ regulatory T cells and CD11b+Gr-1+ myeloid-derived suppressor cells at tumor site. Mixed bone marrow adoptive transfer studies further reveals a T cell-intrinsic role for USP15 in regulating IFN-γ production and tumor development. These findings suggest that T cell intrinsic USP15 deficiency causes excessive production of IFN-γ, which promotes an immunosuppressive tumor microenvironment during MCA-induced primary tumorigenesis.

  15. Multi-level Strategy for Identifying Proteasome-Catalyzed Spliced Epitopes Targeted by CD8+ T Cells during Bacterial Infection

    Directory of Open Access Journals (Sweden)

    Anouk C.M. Platteel

    2017-08-01

    Full Text Available Proteasome-catalyzed peptide splicing (PCPS generates peptides that are presented by MHC class I molecules, but because their identification is challenging, the immunological relevance of spliced peptides remains unclear. Here, we developed a reverse immunology-based multi-level approach to identify proteasome-generated spliced epitopes. Applying this strategy to a murine Listeria monocytogenes infection model, we identified two spliced epitopes within the secreted bacterial phospholipase PlcB that primed antigen-specific CD8+ T cells in L. monocytogenes-infected mice. While reacting to the spliced epitopes, these CD8+ T cells failed to recognize the non-spliced peptide parts in the context of their natural flanking sequences. Thus, we here show that PCPS expands the CD8+ T cell response against L. monocytogenes by exposing spliced epitopes on the cell surface. Moreover, our multi-level strategy opens up opportunities to systematically investigate proteins for spliced epitope candidates and thus strategies for immunotherapies or vaccine design.

  16. Influence of chitosan-chitin nanofiber composites on cytoskeleton structure and the proliferation of rat bone marrow stromal cells.

    Science.gov (United States)

    Kiroshka, Victoria V; Petrova, Valentina A; Chernyakov, Daniil D; Bozhkova, Yulia O; Kiroshka, Katerina V; Baklagina, Yulia G; Romanov, Dmitry P; Kremnev, Roman V; Skorik, Yury A

    2017-01-01

    Chitosan scaffolds have gained much attention in various tissue engineering applications, but the effect of their microstructure on cell-material spatial interactions remains unclear. Our objective was to evaluate the effect of chitosan-based matrices doping with chitin nano-whiskers (CNW) on adhesion, spreading, cytoskeleton structure, and proliferation of rat bone marrow stromal cells (BMSCs). The behavior of BMSCs during culture on chitosan-CNW films was determined by the molecular mass, hydrophobicity, porosity, crosslinking degree, protonation degree and molecular structure of the composite chitosan-CNW films. The shape, spreading area, cytoskeleton structure, and proliferation of BMSCs on chitosan matrices with a crystalline structure and high porosity were similar to that observed for BMSCs cultured on polystyrene tissue culture plates. The amorphous polymer structure and high swelling led to a decrease in the spreading area and cell proliferation. Thus, we can control the behavior of cells in culture (adhesion, spreading, and proliferation) by changing the physico-chemical properties of the chitosan-CNW films.

  17. Lysine demethylase inhibition protects pancreatic β cells from apoptosis and improves β-cell function

    DEFF Research Database (Denmark)

    Backe, Marie Balslev; Andersson, Jan Legaard; Bacos, Karl

    2018-01-01

    ) protects β cells from cytokine-induced apoptosis and reduces type 1 diabetes incidence in animals. We hypothesized that also lysine demethylases (KDMs) regulate β-cell fate in response to inflammatory stress. Expression of the demethylase Kdm6B was upregulated by proinflammatory cytokines suggesting......Transcriptional changes control β-cell survival in response to inflammatory stress. Posttranslational modifications of histone and non-histone transcriptional regulators activate or repress gene transcription, but the link to cell-fate signaling is unclear. Inhibition of lysine deacetylases (KDACs...

  18. miR-320a regulates cell proliferation and apoptosis in multiple myeloma by targeting pre-B-cell leukemia transcription factor 3

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yinghao [Jiangsu Institute of Hematology, First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis Under Ministry of Health, Collaborative Innovation Center of Hematology, Suzhou, 215006 (China); Department of Hematology, Affiliated Hospital of Guizhou Medical University, The Hematopoietic Stem Cell Transplant Center of Guizhou Province, Blood Diseases Diagnosis and Treatment Center of Guizhou Province, Guiyang, 550004, Guizhou Province (China); Wu, Depei, E-mail: wudepei@medmail.com.cn [Jiangsu Institute of Hematology, First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis Under Ministry of Health, Collaborative Innovation Center of Hematology, Suzhou, 215006 (China); Wang, Jishi, E-mail: lgylhlyh@aliyun.com [Department of Hematology, Affiliated Hospital of Guizhou Medical University, The Hematopoietic Stem Cell Transplant Center of Guizhou Province, Blood Diseases Diagnosis and Treatment Center of Guizhou Province, Guiyang, 550004, Guizhou Province (China); Li, Yan; Chai, Xiao; Kang, Qian [Department of Hematology, Affiliated Hospital of Guizhou Medical University, The Hematopoietic Stem Cell Transplant Center of Guizhou Province, Blood Diseases Diagnosis and Treatment Center of Guizhou Province, Guiyang, 550004, Guizhou Province (China)

    2016-05-13

    Aberrant expression of microRNAs (miRNAs) is implicated in cancer development and progression. While miR-320a is reported to be deregulated in many malignancy types, its biological role in multiple myeloma (MM) remains unclear. Here, we observed reduced expression of miR-320a in MM samples and cell lines. Ectopic expression of miR-320a dramatically suppressed cell viability and clonogenicity and induced apoptosis in vitro. Mechanistic investigation led to the identification of Pre-B-cellleukemia transcription factor 3 (PBX3) as a novel and direct downstream target of miR-320a. Interestingly, reintroduction of PBX3 abrogated miR-320a-induced MM cell growth inhibition and apoptosis. In a mouse xenograft model, miR-320a overexpression inhibited tumorigenicity and promoted apoptosis. Our findings collectively indicate that miR-320a inhibits cell proliferation and induces apoptosis in MM cells by directly targeting PBX3, supporting its utility as a novel and potential therapeutic agent for miRNA-based MM therapy. -- Highlights: •Expression of miR-320a in MM cell induces apoptosis in vitro. •miR-320a represses PBX3 via targeting specific sequences in the 3′UTR region. •Exogenous expression of PBX3 reverses the effects of miR-320a in inhibiting MM cell growth and promoting apoptosis. •Overexpression of miR-320a inhibits tumor growth and increases apoptosis in vivo.

  19. Dancing Styles of Collective Cell Migration: Image-Based Computational Analysis of JRAB/MICAL-L2.

    Science.gov (United States)

    Sakane, Ayuko; Yoshizawa, Shin; Yokota, Hideo; Sasaki, Takuya

    2018-01-01

    Collective cell migration is observed during morphogenesis, angiogenesis, and wound healing, and this type of cell migration also contributes to efficient metastasis in some kinds of cancers. Because collectively migrating cells are much better organized than a random assemblage of individual cells, there seems to be a kind of order in migrating clusters. Extensive research has identified a large number of molecules involved in collective cell migration, and these factors have been analyzed using dramatic advances in imaging technology. To date, however, it remains unclear how myriad cells are integrated as a single unit. Recently, we observed unbalanced collective cell migrations that can be likened to either precision dancing or awa-odori , Japanese traditional dancing similar to the style at Rio Carnival, caused by the impairment of the conformational change of JRAB/MICAL-L2. This review begins with a brief history of image-based computational analyses on cell migration, explains why quantitative analysis of the stylization of collective cell behavior is difficult, and finally introduces our recent work on JRAB/MICAL-L2 as a successful example of the multidisciplinary approach combining cell biology, live imaging, and computational biology. In combination, these methods have enabled quantitative evaluations of the "dancing style" of collective cell migration.

  20. Opposing roles for RhoH GTPase during T-cell migration and activation

    Science.gov (United States)

    Baker, Christina M.; Comrie, William A.; Hyun, Young-Min; Chung, Hung-Li; Fedorchuk, Christine A.; Lim, Kihong; Brakebusch, Cord; McGrath, James L.; Waugh, Richard E.; Meier-Schellersheim, Martin; Kim, Minsoo

    2012-01-01

    T cells spend the majority of their time perusing lymphoid organs in search of cognate antigen presented by antigen presenting cells (APCs) and then quickly recirculate through the bloodstream to another lymph node. Therefore, regulation of a T-cell response is dependent upon the ability of cells to arrive in the correct location following chemokine gradients (“go” signal) as well as to receive appropriate T-cell receptor (TCR) activation signals upon cognate antigen recognition (“stop” signal). However, the mechanisms by which T cells regulate these go and stop signals remain unclear. We found that overexpression of the hematopoietic-specific RhoH protein in the presence of chemokine signals resulted in decreased Rap1–GTP and LFA-1 adhesiveness to ICAM-1, thus impairing T-cell chemotaxis; while in the presence of TCR signals, there were enhanced and sustained Rap1–GTP and LFA-1 activation as well as prolonged T:APC conjugates. RT-PCR analyses of activated CD4+ T cells and live images of T-cell migration and immunological synapse (IS) formation revealed that functions of RhoH took place primarily at the levels of transcription and intracellular distribution. Thus, we conclude that RhoH expression provides a key molecular determinant that allows T cells to switch between sensing chemokine-mediated go signals and TCR-dependent stop signals. PMID:22689994

  1. p53-Independent thermosensitization by mitomycin C in human non-small cell lung carcinoma cells

    International Nuclear Information System (INIS)

    Jin, Z.-H.; Matsumoto, H.; Hayashi, S.; Shioura, H.; Kitai, R.; Kano, E.; Hatashita, M.

    2003-01-01

    The combined treatment with hyperthermia and chemotherapeutic drugs such as cisplatin (CDDP), doxorubicin (DOX) and mitomycin C (MMC) has been widely adopted as a strategy of interdisciplinary cancer therapy to obtain greater therapeutic benefits. However, the involved mechanisms of the interactive cytotoxic effects of hyperthermia and MMC remain unclear. To elucidate the relationship between p53 functions and the interactive effects of the combined treatment with mild-hyperthermia and MMC, we examined the potentiation of cytotoxic effects, the induction of apoptosis, the changes in cell cycles and the accumulation of Hsp72 after the combined treatment with hyperthermia at 42 degree C and MMC using human non-small cell lung carcinoma H1299 transfectants with either null, wild-type (wt) or mutant (m) p53 gene. H1299/null, H1299/wtp53 and H1299/mp53 cells showed similar sensitivities to either hyperthermia at 42 degree C alone or MMC alone. The combined treatment resulted in a synergistically enhanced cytotoxicity in H1299 transfectants in a p53-independent manner. The mechanisms involved an enhancement of heat-induced apoptosis and a modulation of the cell cycle distribution by the combined treatment. The accumulation of Hsp72 was not suppressed by the combined treatment, as is not the case of the combined treatment with hyperthermia and either CDDP (1) or bleomycin (2). Our findings demonstrate a p53-independent mechanism for a synergistically cytotoxic enhancement by the combined treatment with mild-hyperthermia and MMC

  2. Protein kinase C β inhibits autophagy and sensitizes cervical cancer Hela cells to cisplatin.

    Science.gov (United States)

    Li, Na; Zhang, Wei

    2017-04-28

    Recently, autophagy has been indicated to play an essential role in various biological events, such as the response of cervical cancer cells to chemotherapy. However, the exact signalling mechanism that regulates autophagy during chemotherapy remains unclear. In the present study, we investigated the regulation by cisplatin on protein kinase C β (PKC β), on B-cell lymphoma 2 (Bcl-2) and on apoptosis in cervical cancer Hela cells. And then we examined the regulation by cisplatin on autophagy and the role of autophagy on the chemotherapy in Hela cells. In addition, the regulation of the PKC β on the autophagy was also investigated. Our results indicated that cisplatin promoted PKC β in Hela cells. The PKC β inhibitor reduced the cisplatin-induced apoptosis, whereas increased the cisplatin-induced autophagy in Hela cells. On the other side, the PKC β overexpression aggravated the cisplatin-induced apoptosis, whereas down-regulated the cisplatin-induced autophagy. Taken together, our study firstly recognized the involvement of PKC β in the cytotoxicity of cisplatin via inhibiting autophagy in cervical cancer cells. We propose that PKC β would sensitize cervical cancer cells to chemotherapy via reducing the chemotherapy induced autophagy in cancer cells. © 2017 The Author(s).

  3. Sca-1+ cardiosphere-derived cells are enriched for Isl1-expressing cardiac precursors and improve cardiac function after myocardial injury.

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    Jianqin Ye

    Full Text Available BACKGROUND: Endogenous cardiac progenitor cells are a promising option for cell-therapy for myocardial infarction (MI. However, obtaining adequate numbers of cardiac progenitors after MI remains a challenge. Cardiospheres (CSs have been proposed to have cardiac regenerative properties; however, their cellular composition and how they may be influenced by the tissue milieu remains unclear. METHODOLOGY/PRINCIPAL FINDING: Using "middle aged" mice as CSs donors, we found that acute MI induced a dramatic increase in the number of CSs in a mouse model of MI, and this increase was attenuated back to baseline over time. We also observed that CSs from post-MI hearts engrafted in ischemic myocardium induced angiogenesis and restored cardiac function. To determine the role of Sca-1(+CD45(- cells within CSs, we cloned these from single cell isolates. Expression of Islet-1 (Isl1 in Sca-1(+CD45(- cells from CSs was 3-fold higher than in whole CSs. Cloned Sca-1(+CD45(- cells had the ability to differentiate into cardiomyocytes, endothelial cells and smooth muscle cells in vitro. We also observed that cloned cells engrafted in ischemic myocardium induced angiogenesis, differentiated into endothelial and smooth muscle cells and improved cardiac function in post-MI hearts. CONCLUSIONS/SIGNIFICANCE: These studies demonstrate that cloned Sca-1(+CD45(- cells derived from CSs from infarcted "middle aged" hearts are enriched for second heart field (i.e., Isl-1(+ precursors that give rise to both myocardial and vascular tissues, and may be an appropriate source of progenitor cells for autologous cell-therapy post-MI.

  4. Curcumin Enhances Cytotoxic Effects of Bortezomib in Human Multiple Myeloma H929 Cells: Potential Roles of NF-κB/JNK

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    Qing-Xian Bai

    2012-04-01

    Full Text Available Combined curcumin and PS-341 treatment has been reported to enhance cytotoxicity and minimize adverse effects through ERK and p38MAPK mechanisms in human multiple myeloma cells. However, whether JNK plays similar role in this process remains unclear. In the present study, we found combined treatment altered NF-κB p65 expressions and distributions in multiple myeloma H929 cells. Western blot analysis showed combined treatment inactivated NF-κB while activated JNK signaling. Pre-treatment with JNK inhibitor SP600125 could attenuate NF-κB inactivation and restored H929 cells’ survival. These results suggested that curcumin might enhance the cytotoxicity of PS-341 by interacting with NF-κB, at least in part, through JNK mechanism.

  5. Roles of IFN-γ and γδ T cells in protective immunity against blood-stage malaria

    Directory of Open Access Journals (Sweden)

    Shin-Ichi eInoue

    2013-08-01

    Full Text Available Malaria is caused by infection with Plasmodium parasites. Various studies with knockout mice have indicated that IFN-γ plays essential roles in protective immunity against blood-stage Plasmodium infection. However, after Plasmodium infection, increased IFN-γ production by various types of cells is involved not only in protective immunity, but also in immunopathology. Recent reports have shown that IFN-γ acts as a pro-inflammatory cytokine to induce not only the activation of macrophages, but also the generation of uncommon myelolymphoid progenitor cells after Plasmodium infection. However, the effects of IFN-γ on hematopoietic stem cells and progenitor cells are unclear. Therefore, the regulation of hematopoiesis by IFN-γ during Plasmodium infection remains to be clarified. Although there are conflicting reports concerning the significance of γδ T cells in protective immunity against Plasmodium infection, γδ T cells may respond to infection and produce IFN-γ as innate immune cells in the early phase of blood-stage malaria. Our recent studies have shown that γδ T cells express CD40 ligand and produce IFN-γ after Plasmodium infection, resulting in the enhancement of dendritic cell activation as part of the immune response to eliminate Plasmodium parasites. These data suggest that the function of γδ T cells is similar to that of NK cells. Although several reports suggest that γδ T cells have the potential to act as memory cells for various infections, it remains to be determined whether memory γδ T cells are generated by Plasmodium infection and whether memory γδ T cells can contribute to the host defense against re-infection with Plasmodium. Here, we summarize and discuss the effects of IFN-γ and the various functions of γδ T cells in blood-stage Plasmodium infection.

  6. Vorinostat induces reactive oxygen species and DNA damage in acute myeloid leukemia cells.

    Directory of Open Access Journals (Sweden)

    Luca A Petruccelli

    Full Text Available Histone deacetylase inhibitors (HDACi are promising anti-cancer agents, however, their mechanisms of action remain unclear. In acute myeloid leukemia (AML cells, HDACi have been reported to arrest growth and induce apoptosis. In this study, we elucidate details of the DNA damage induced by the HDACi vorinostat in AML cells. At clinically relevant concentrations, vorinostat induces double-strand breaks and oxidative DNA damage in AML cell lines. Additionally, AML patient blasts treated with vorinostat display increased DNA damage, followed by an increase in caspase-3/7 activity and a reduction in cell viability. Vorinostat-induced DNA damage is followed by a G2-M arrest and eventually apoptosis. We found that pre-treatment with the antioxidant N-acetyl cysteine (NAC reduces vorinostat-induced DNA double strand breaks, G2-M arrest and apoptosis. These data implicate DNA damage as an important mechanism in vorinostat-induced growth arrest and apoptosis in both AML cell lines and patient-derived blasts. This supports the continued study and development of vorinostat in AMLs that may be sensitive to DNA-damaging agents and as a combination therapy with ionizing radiation and/or other DNA damaging agents.

  7. Vorinostat Induces Reactive Oxygen Species and DNA Damage in Acute Myeloid Leukemia Cells

    Science.gov (United States)

    Pettersson, Filippa; Retrouvey, Hélène; Skoulikas, Sophia; Miller, Wilson H.

    2011-01-01

    Histone deacetylase inhibitors (HDACi) are promising anti-cancer agents, however, their mechanisms of action remain unclear. In acute myeloid leukemia (AML) cells, HDACi have been reported to arrest growth and induce apoptosis. In this study, we elucidate details of the DNA damage induced by the HDACi vorinostat in AML cells. At clinically relevant concentrations, vorinostat induces double-strand breaks and oxidative DNA damage in AML cell lines. Additionally, AML patient blasts treated with vorinostat display increased DNA damage, followed by an increase in caspase-3/7 activity and a reduction in cell viability. Vorinostat-induced DNA damage is followed by a G2-M arrest and eventually apoptosis. We found that pre-treatment with the antioxidant N-acetyl cysteine (NAC) reduces vorinostat-induced DNA double strand breaks, G2-M arrest and apoptosis. These data implicate DNA damage as an important mechanism in vorinostat-induced growth arrest and apoptosis in both AML cell lines and patient-derived blasts. This supports the continued study and development of vorinostat in AMLs that may be sensitive to DNA-damaging agents and as a combination therapy with ionizing radiation and/or other DNA damaging agents. PMID:21695163

  8. Pancreatic acinar cells-derived cyclophilin A promotes pancreatic damage by activating NF-κB pathway in experimental pancreatitis

    International Nuclear Information System (INIS)

    Yu, Ge; Wan, Rong; Hu, Yanling; Ni, Jianbo; Yin, Guojian; Xing, Miao; Shen, Jie; Tang, Maochun; Chen, Congying; Fan, Yuting; Xiao, Wenqin; Zhao, Yan; Wang, Xingpeng

    2014-01-01

    Highlights: • CypA is upregulated in experimental pancreatitis. • CCK induces expression and release of CypA in acinar cell in vitro. • rCypA aggravates CCK-induced acinar cell death and inflammatory cytokine production. • rCypA activates the NF-κB pathway in acinar cells in vitro. - Abstract: Inflammation triggered by necrotic acinar cells contributes to the pathophysiology of acute pancreatitis (AP), but its precise mechanism remains unclear. Recent studies have shown that Cyclophilin A (CypA) released from necrotic cells is involved in the pathogenesis of several inflammatory diseases. We therefore investigated the role of CypA in experimental AP induced by administration of sodium taurocholate (STC). CypA was markedly upregulated and widely expressed in disrupted acinar cells, infiltrated inflammatory cells, and tubular complexes. In vitro, it was released from damaged acinar cells by cholecystokinin (CCK) induction. rCypA (recombinant CypA) aggravated CCK-induced acinar cell necrosis, promoted nuclear factor (NF)-κB p65 activation, and increased cytokine production. In conclusion, CypA promotes pancreatic damage by upregulating expression of inflammatory cytokines of acinar cells via the NF-κB pathway

  9. Pancreatic acinar cells-derived cyclophilin A promotes pancreatic damage by activating NF-κB pathway in experimental pancreatitis

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Ge [Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai (China); Wan, Rong [Department of Gastroenterology, Shanghai First People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Hu, Yanling [Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai (China); Ni, Jianbo [Department of Gastroenterology, Shanghai First People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Yin, Guojian; Xing, Miao [Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai (China); Shen, Jie [Department of Gastroenterology, Shanghai First People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Tang, Maochun [Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai (China); Chen, Congying [Department of Gastroenterology, Shanghai First People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Fan, Yuting; Xiao, Wenqin; Zhao, Yan [Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai (China); Wang, Xingpeng, E-mail: wangxingpeng@hotmail.com [Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai (China); Department of Gastroenterology, Shanghai First People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); and others

    2014-01-31

    Highlights: • CypA is upregulated in experimental pancreatitis. • CCK induces expression and release of CypA in acinar cell in vitro. • rCypA aggravates CCK-induced acinar cell death and inflammatory cytokine production. • rCypA activates the NF-κB pathway in acinar cells in vitro. - Abstract: Inflammation triggered by necrotic acinar cells contributes to the pathophysiology of acute pancreatitis (AP), but its precise mechanism remains unclear. Recent studies have shown that Cyclophilin A (CypA) released from necrotic cells is involved in the pathogenesis of several inflammatory diseases. We therefore investigated the role of CypA in experimental AP induced by administration of sodium taurocholate (STC). CypA was markedly upregulated and widely expressed in disrupted acinar cells, infiltrated inflammatory cells, and tubular complexes. In vitro, it was released from damaged acinar cells by cholecystokinin (CCK) induction. rCypA (recombinant CypA) aggravated CCK-induced acinar cell necrosis, promoted nuclear factor (NF)-κB p65 activation, and increased cytokine production. In conclusion, CypA promotes pancreatic damage by upregulating expression of inflammatory cytokines of acinar cells via the NF-κB pathway.

  10. Glucose Regulates Cyclin D2 Expression in Quiescent and Replicating Pancreatic β-Cells Through Glycolysis and Calcium Channels

    Science.gov (United States)

    Salpeter, Seth J.; Klochendler, Agnes; Weinberg-Corem, Noa; Porat, Shay; Granot, Zvi; Shapiro, A. M. James; Magnuson, Mark A.; Eden, Amir; Grimsby, Joseph; Glaser, Benjamin

    2011-01-01

    Understanding the molecular triggers of pancreatic β-cell proliferation may facilitate the development of regenerative therapies for diabetes. Genetic studies have demonstrated an important role for cyclin D2 in β-cell proliferation and mass homeostasis, but its specific function in β-cell division and mechanism of regulation remain unclear. Here, we report that cyclin D2 is present at high levels in the nucleus of quiescent β-cells in vivo. The major regulator of cyclin D2 expression is glucose, acting via glycolysis and calcium channels in the β-cell to control cyclin D2 mRNA levels. Furthermore, cyclin D2 mRNA is down-regulated during S-G2-M phases of each β-cell division, via a mechanism that is also affected by glucose metabolism. Thus, glucose metabolism maintains high levels of nuclear cyclin D2 in quiescent β-cells and modulates the down-regulation of cyclin D2 in replicating β-cells. These data challenge the standard model for regulation of cyclin D2 during the cell division cycle and suggest cyclin D2 as a molecular link between glucose levels and β-cell replication. PMID:21521747

  11. Live cell imaging reveals marked variability in myoblast proliferation and fate

    Science.gov (United States)

    2013-01-01

    Background During the process of muscle regeneration, activated stem cells termed satellite cells proliferate, and then differentiate to form new myofibers that restore the injured area. Yet not all satellite cells contribute to muscle repair. Some continue to proliferate, others die, and others become quiescent and are available for regeneration following subsequent injury. The mechanisms that regulate the adoption of different cell fates in a muscle cell precursor population remain unclear. Methods We have used live cell imaging and lineage tracing to study cell fate in the C2 myoblast line. Results Analyzing the behavior of individual myoblasts revealed marked variability in both cell cycle duration and viability, but similarities between cells derived from the same parental lineage. As a consequence, lineage sizes and outcomes differed dramatically, and individual lineages made uneven contributions toward the terminally differentiated population. Thus, the cohort of myoblasts undergoing differentiation at the end of an experiment differed dramatically from the lineages present at the beginning. Treatment with IGF-I increased myoblast number by maintaining viability and by stimulating a fraction of cells to complete one additional cell cycle in differentiation medium, and as a consequence reduced the variability of the terminal population compared with controls. Conclusion Our results reveal that heterogeneity of responses to external cues is an intrinsic property of cultured myoblasts that may be explained in part by parental lineage, and demonstrate the power of live cell imaging for understanding how muscle differentiation is regulated. PMID:23638706

  12. Taurine Promotes the Cartilaginous Differentiation of Human Umbilical Cord-Derived Mesenchymal Stem Cells in Vitro.

    Science.gov (United States)

    Yao, Xiuhua; Huang, Huiling; Li, Zhou; Liu, Xiaohua; Fan, Weijia; Wang, Xinping; Sun, Xuelian; Zhu, Jianmin; Zhou, Hongrui; Wei, Huaying

    2017-08-01

    Taurine has been reported to influence osteogenic differentiation, but the role of taurine on cartilaginous differentiation using human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) remains unclear. In this study, we investigated the effect of taurine (0, 1, 5 and 10 mM) on the proliferation and chondrogenesis of hUC-MSCs by analyzing cell proliferation, accumulation of glycosaminoglycans and expression of cartilage specific mRNA. The results show though taurine did not affected the proliferation of hUC-MSCs, 5 mM of taurine is sufficient to enhanced the accumulation of glycosaminoglycans and up-regulate cartilage specific mRNA expression, namely collagen type II, aggrecan and SOX9. Taurine also inhibits chondrocyte dedifferentiation by reducing expression of collagen type I mRNA. Taken together, our study reveals that taurine promotes and maintains the chondrogenesis of hUC-MSCs.

  13. BID links ferroptosis to mitochondrial cell death pathways.

    Science.gov (United States)

    Neitemeier, Sandra; Jelinek, Anja; Laino, Vincenzo; Hoffmann, Lena; Eisenbach, Ina; Eying, Roman; Ganjam, Goutham K; Dolga, Amalia M; Oppermann, Sina; Culmsee, Carsten

    2017-08-01

    Ferroptosis has been defined as an oxidative and iron-dependent pathway of regulated cell death that is distinct from caspase-dependent apoptosis and established pathways of death receptor-mediated regulated necrosis. While emerging evidence linked features of ferroptosis induced e.g. by erastin-mediated inhibition of the X c - system or inhibition of glutathione peroxidase 4 (Gpx4) to an increasing number of oxidative cell death paradigms in cancer cells, neurons or kidney cells, the biochemical pathways of oxidative cell death remained largely unclear. In particular, the role of mitochondrial damage in paradigms of ferroptosis needs further investigation. In the present study, we find that erastin-induced ferroptosis in neuronal cells was accompanied by BID transactivation to mitochondria, loss of mitochondrial membrane potential, enhanced mitochondrial fragmentation and reduced ATP levels. These hallmarks of mitochondrial demise are also established features of oxytosis, a paradigm of cell death induced by X c - inhibition by millimolar concentrations of glutamate. Bid knockout using CRISPR/Cas9 approaches preserved mitochondrial integrity and function, and mediated neuroprotective effects against both, ferroptosis and oxytosis. Furthermore, the BID-inhibitor BI-6c9 inhibited erastin-induced ferroptosis, and, in turn, the ferroptosis inhibitors ferrostatin-1 and liproxstatin-1 prevented mitochondrial dysfunction and cell death in the paradigm of oxytosis. These findings show that mitochondrial transactivation of BID links ferroptosis to mitochondrial damage as the final execution step in this paradigm of oxidative cell death. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Melatonin Promotes Apoptosis of Oxaliplatin-resistant Colorectal Cancer Cells Through Inhibition of Cellular Prion Protein.

    Science.gov (United States)

    Lee, Jun Hee; Yoon, Yeo Min; Han, Yong-Seok; Yun, Chul Won; Lee, Sang Hun

    2018-04-01

    Drug resistance restricts the efficacy of chemotherapy in colorectal cancer. However, the detailed molecular mechanism of drug resistance in colorectal cancer cells remains unclear. The level of cellular prion protein (PrP C ) in oxaliplatin-resistant colorectal cancer (SNU-C5/Oxal-R) cells was assessed. PrP C level in SNU-C5/Oxal-R cells was significantly increased compared to that in wild-type (SNU-C5) cells. Superoxide dismutase and catalase activities were higher in SNU-C5/Oxal-R cells than in SNU-C5 cells. Treatment of SNU-C5/Oxal-R cells with oxaliplatin and melatonin reduced PrP C expression, while suppressing antioxidant enzyme activity and increasing superoxide anion generation. In SNU-C5/Oxal-R cells, endoplasmic reticulum stress and apoptosis were significantly increased following co-treatment with oxaliplatin and melatonin compared to treatment with oxaliplatin alone. Co-treatment with oxaliplatin and melatonin increased endoplasmic reticulum stress in and apoptosis of SNU-C5/Oxal-R cells through inhibition of PrP C , suggesting that PrP C could be a key molecule in oxaliplatin resistance of colorectal cancer cells. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  15. Mesenchymal Stromal Cell Therapy for Pancreatitis: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Sara M. Ahmed

    2018-01-01

    Full Text Available Background. Based on animal studies, adult mesenchymal stromal cells (MSCs are promising for the treatment of pancreatitis. However, the best type of this form of cell therapy and its mechanism of action remain unclear. Methods. We searched the PubMed, Web of Science, Scopus, Google Scholar, and Clinical Trials.gov websites for studies using MSCs as a therapy for both acute and chronic pancreatitis published until September 2017. Results. We identified 276 publications; of these publications, 18 met our inclusion criteria. In animal studies, stem cell therapy was applied more frequently for acute pancreatitis than for chronic pancreatitis. No clinical trials were identified. MSC therapy ameliorated pancreatic inflammation in acute pancreatitis and pancreatic fibrosis in chronic pancreatitis. Bone marrow and umbilical cord MSCs were the most frequently administered cell types. Due to the substantial heterogeneity among the studies regarding the type, source, and dose of MSCs used, conducting a meta-analysis was not feasible to determine the best type of MSCs. Conclusion. The available data were insufficient for determining the best type of MSCs for the treatment of acute or chronic pancreatitis; therefore, clinical trials investigating the use of MSCs as therapy for pancreatitis are not warranted.

  16. Memory T follicular helper CD4 T cells

    Directory of Open Access Journals (Sweden)

    J. Scott eHale

    2015-02-01

    Full Text Available T follicular helper (Tfh cells are the subset of CD4 T helper cells that are required for generation and maintenance of germinal center reactions and the generation of long-lived humoral immunity. This specialized T helper subset provides help to cognate B cells via their expression of CD40 ligand, IL-21, IL-4, and other molecules. Tfh cells are characterized by their expression of the chemokine receptor CXCR5, expression of the transcriptional repressor Bcl6, and their capacity to migrate to the follicle and promote germinal center B cell responses. Until recently, it remained unclear whether Tfh cells differentiated into memory cells and whether they maintain their Tfh commitment at the memory phase. This review will highlight several recent studies that support the idea of Tfh-committed CD4 T cells at the memory stage of the immune response. The implication of these findings is that memory Tfh cells retain their capacity to recall their Tfh-specific effector functions upon reactivation to provide help for B cell responses and play an important role in prime and boost vaccination or during recall responses to infection. The markers that are useful for distinguishing Tfh effector and memory cells, as well as the limitations of using these markers will be discussed. Tfh effector and memory generation, lineage maintenance, and plasticity relative to other T helper lineages (Th1, Th2, Th17, etc will also be discussed. Ongoing discoveries regarding the maintenance and lineage stability versus plasticity of memory Tfh cells will improve strategies that utilize CD4 T cell memory to modulate antibody responses during prime and boost vaccination.

  17. Involvement of dendritic cells in allograft rejection new implications of dendritic cell-endothelial cell interactions.

    Science.gov (United States)

    Schlichting, C L; Schareck, W D; Kofler, S; Weis, M

    2007-04-01

    For almost half a century immunologists have tried to tear down the MHC barrier, which separates two unrelated individuals during transplantation. Latest experimental data suggest that a breakthrough in vitro is imminent. Dendritic cells (DCs), which activate naïve allo-reactive T-cells (TCs), play a central role in the establishment of allo-antigen-specific immunity. Allograft solid organ rejection is initiated at the foreign endothelial cell (EC) layer, which forms an immunogenic barrier for migrating DCs. Thus, DC/EC interactions might play a crucial role in antigen-specific allograft rejection. Organ rejection is mediated by host allo-reactive TCs, which are activated by donor DCs (direct activation) or host DCs (indirect activation). Direct allo-antigen presentation by regulatory dendritic cells (DCreg) can play an instructive role towards tolerance induction. Several groups established that, DCregs, if transplanted beforehand, enter host thymus, spleen, or bone marrow where they might eventually establish allo-antigen-specific tolerance. A fundamental aspect of DC function is migration throughout the entire organism. After solid organ transplantation, host DCs bind to ECs, invade allograft tissues, and finally transmigrate into lymphoid vessels and secondary lymphoid organs, where they present allo-antigens to naïve host TCs. Recent data suggest that in vitro manipulated DCregs may mediate allo-transplantation tolerance induction. However, the fundamental mechanisms on how such DCregs cause host TCs in the periphery towards tolerance remain unclear. One very promising experimental concept is the simultaneous manipulation of DC direct and indirect TC activation/suppression, towards donor antigen-specific allo-transplantation tolerance. The allo-antigen-specific long-term tolerance induction mediated by DCreg pre-transplantation (with simultaneous short-term immunosuppression) has become reproducible in the laboratory animal setting. Despite the shortcomings

  18. Effective internalization of U251-MG-secreted exosomes into cancer cells and characterization of their lipid components.

    Science.gov (United States)

    Toda, Yuki; Takata, Kazuyuki; Nakagawa, Yuko; Kawakami, Hikaru; Fujioka, Shusuke; Kobayashi, Kazuya; Hattori, Yasunao; Kitamura, Yoshihisa; Akaji, Kenichi; Ashihara, Eishi

    2015-01-16

    Exosomes, the natural vehicles of various biological molecules, have been examined in several research fields including drug delivery. Although understanding of the biological functions of exosomes has increased, how exosomes are transported between cells remains unclear. We hypothesized that cell tropism is important for effective exosomal intercellular communication and that parental cells regulate exosome movement by modulating constituent exosomal molecules. Herein, we demonstrated the strong translocation of glioblastoma-derived exosomes (U251exo) into their parental (U251) cells, breast cancer (MDA-MB-231) cells, and fibrosarcoma (HT-1080). Furthermore, disruption of proteins of U251exo by enzymatic treatment did not affect their uptake. Therefore, we focused on lipid molecules of U251exo with the expectation that they are crucial for effective incorporation of U251exo by cancer cells. Phosphatidylethanolamine was identified as a unique lipid component of U251-MG cell-derived extracellular vesicles. From these results, valuable insight is provided into the targeting of U251exo to cancer cells, which will help to develop a cancer-targeted drug delivery system. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Adipose progenitor cells increase fibronectin matrix strain and unfolding in breast tumors

    Science.gov (United States)

    Chandler, E. M.; Saunders, M. P.; Yoon, C. J.; Gourdon, D.; Fischbach, C.

    2011-02-01

    Increased stiffness represents a hallmark of breast cancer that has been attributed to the altered physicochemical properties of the extracellular matrix (ECM). However, the role of fibronectin (Fn) in modulating the composition and mechanical properties of the tumor-associated ECM remains unclear. We have utilized a combination of biochemical and physical science tools to evaluate whether paracrine signaling between breast cancer cells and adipose progenitor cells regulates Fn matrix assembly and stiffness enhancement in the tumor stroma. In particular, we utilized fluorescence resonance energy transfer imaging to map the molecular conformation and stiffness of Fn that has been assembled by 3T3-L1 preadipocytes in response to conditioned media from MDA-MB231 breast cancer cells. Our results reveal that soluble factors secreted by tumor cells promote Fn expression, unfolding, and stiffening by adipose progenitor cells and that transforming growth factor-β serves as a soluble cue underlying these changes. In vivo experiments using orthotopic co-transplantation of primary human adipose-derived stem cells and MDA-MB231 into SCID mice support the pathological relevance of our results. Insights gained by these studies advance our understanding of the role of Fn in mammary tumorigenesis and may ultimately lead to improved anti-cancer therapies.

  20. Adipose progenitor cells increase fibronectin matrix strain and unfolding in breast tumors

    International Nuclear Information System (INIS)

    Chandler, E M; Saunders, M P; Yoon, C J; Fischbach, C; Gourdon, D

    2011-01-01

    Increased stiffness represents a hallmark of breast cancer that has been attributed to the altered physicochemical properties of the extracellular matrix (ECM). However, the role of fibronectin (Fn) in modulating the composition and mechanical properties of the tumor-associated ECM remains unclear. We have utilized a combination of biochemical and physical science tools to evaluate whether paracrine signaling between breast cancer cells and adipose progenitor cells regulates Fn matrix assembly and stiffness enhancement in the tumor stroma. In particular, we utilized fluorescence resonance energy transfer imaging to map the molecular conformation and stiffness of Fn that has been assembled by 3T3-L1 preadipocytes in response to conditioned media from MDA-MB231 breast cancer cells. Our results reveal that soluble factors secreted by tumor cells promote Fn expression, unfolding, and stiffening by adipose progenitor cells and that transforming growth factor-β serves as a soluble cue underlying these changes. In vivo experiments using orthotopic co-transplantation of primary human adipose-derived stem cells and MDA-MB231 into SCID mice support the pathological relevance of our results. Insights gained by these studies advance our understanding of the role of Fn in mammary tumorigenesis and may ultimately lead to improved anti-cancer therapies

  1. Enhancer Analysis Unveils Genetic Interactions between TLX and SOX2 in Neural Stem Cells and In Vivo Reprogramming.

    Science.gov (United States)

    Islam, Mohammed M; Smith, Derek K; Niu, Wenze; Fang, Sanhua; Iqbal, Nida; Sun, Guoqiang; Shi, Yanhong; Zhang, Chun-Li

    2015-11-10

    The orphan nuclear receptor TLX is a master regulator of postnatal neural stem cell (NSC) self-renewal and neurogenesis; however, it remains unclear how TLX expression is precisely regulated in these tissue-specific stem cells. Here, we show that a highly conserved cis-element within the Tlx locus functions to drive gene expression in NSCs. We demonstrate that the transcription factors SOX2 and MYT1 specifically interact with this genomic element to directly regulate Tlx enhancer activity in vivo. Knockdown experiments further reveal that SOX2 dominantly controls endogenous expression of TLX, whereas MYT1 only plays a modulatory role. Importantly, TLX is essential for SOX2-mediated in vivo reprogramming of astrocytes and itself is also sufficient to induce neurogenesis in the adult striatum. Together, these findings unveil functional genetic interactions among transcription factors that are critical to NSCs and in vivo cell reprogramming.

  2. MicroRNAs as tumour suppressors in canine and human melanoma cells and as a prognostic factor in canine melanomas.

    Science.gov (United States)

    Noguchi, S; Mori, T; Hoshino, Y; Yamada, N; Maruo, K; Akao, Y

    2013-06-01

    Malignant melanoma (MM) is one of the most aggressive cancers in dogs and in humans. However, the molecular mechanisms of its development and progression remain unclear. Presently, we examined the expression profile of microRNAs (miRs) in canine oral MM tissues and paired normal oral mucosa tissues by using the microRNA-microarray assay and quantitative RT-PCR. Importantly, a decreased expression of miR-203 was significantly associated with a shorter survival time. Also, miR-203 and -205 were markedly down-regulated in canine and human MM cell lines tested. Furthermore, the ectopic expression of miR-205 had a significant inhibitory effect on the cell growth of canine and human melanoma cells tested by targeting erbb3. Our data suggest that miR-203 is a new prognostic factor in canine oral MMs and that miR-205 functions as a tumour suppressor by targeting erbb3 in both canine and human MM cells. © 2011 John Wiley & Sons Ltd.

  3. Completely ES cell-derived mice produced by tetraploid complementation using inner cell mass (ICM deficient blastocysts.

    Directory of Open Access Journals (Sweden)

    Duancheng Wen

    Full Text Available Tetraploid complementation is often used to produce mice from embryonic stem cells (ESCs by injection of diploid (2n ESCs into tetraploid (4n blastocysts (ESC-derived mice. This method has also been adapted to mouse cloning and the derivation of mice from induced pluripotent stem (iPS cells. However, the underlying mechanism(s of the tetraploid complementation remains largely unclear. Whether this approach can give rise to completely ES cell-derived mice is an open question, and has not yet been unambiguously proven. Here, we show that mouse tetraploid blastocysts can be classified into two groups, according to the presence or absence of an inner cell mass (ICM. We designate these as type a (presence of ICM at blastocyst stage or type b (absence of ICM. ESC lines were readily derived from type a blastocysts, suggesting that these embryos retain a pluripotent epiblast compartment; whereas the type b blastocysts possessed very low potential to give rise to ESC lines, suggesting that they had lost the pluripotent epiblast. When the type a blastocysts were used for tetraploid complementation, some of the resulting mice were found to be 2n/4n chimeric; whereas when type b blastocysts were used as hosts, the resulting mice are all completely ES cell-derived, with the newborn pups displaying a high frequency of abdominal hernias. Our results demonstrate that completely ES cell-derived mice can be produced using ICM-deficient 4n blastocysts, and provide evidence that the exclusion of tetraploid cells from the fetus in 2n/4n chimeras can largely be attributed to the formation of ICM-deficient blastocysts.

  4. Evolution of mitochondrial cell death pathway: Proapoptotic role of HtrA2/Omi in Drosophila

    International Nuclear Information System (INIS)

    Igaki, Tatsushi; Suzuki, Yasuyuki; Tokushige, Naoko; Aonuma, Hiroka; Takahashi, Ryosuke; Miura, Masayuki

    2007-01-01

    Despite the essential role of mitochondria in a variety of mammalian cell death processes, the involvement of mitochondrial pathway in Drosophila cell death has remained unclear. To address this, we cloned and characterized DmHtrA2, a Drosophila homolog of a mitochondrial serine protease HtrA2/Omi. We show that DmHtrA2 normally resides in mitochondria and is up-regulated by UV-irradiation. Upon receipt of apoptotic stimuli, DmHtrA2 is translocated to extramitochondrial compartment; however, unlike its mammalian counterpart, the extramitochondrial DmHtrA2 does not diffuse throughout the cytosol but stays near the mitochondria. RNAi-mediated knock-down of DmHtrA2 in larvae or adult flies results in a resistance to stress stimuli. DmHtrA2 specifically cleaves Drosophila inhibitor-of-apoptosis protein 1 (DIAP1), a cellular caspase inhibitor, and induces cell death both in vitro and in vivo as potent as other fly cell death proteins. Our observations suggest that DmHtrA2 promotes cell death through a cleavage of DIAP1 in the vicinity of mitochondria, which may represent a prototype of mitochondrial cell death pathway in evolution

  5. Opposite roles of MRF4 and MyoD in cell proliferation and myogenic differentiation

    International Nuclear Information System (INIS)

    Jin Xun; Kim, Jong-Gun; Oh, Myung-Joo; Oh, Ho-Yeon; Sohn, Young-Woo; Pian, Xumin; Yin, Jin Long; Beck, Samuel; Lee, Namkyung; Son, Jeesoo; Kim, Hyunggee; Yan Changguo; Wang Jihui; Choi, Yun-Jaie; Whang, Kwang Youn

    2007-01-01

    The basic helix-loop-helix myogenic regulatory factors play critical roles in skeletal myogenesis. Among the myogenic regulatory factors (MRFs), MRF4 shows a biphasic expression pattern during the formation of myotomes, although its function remains unclear. In this study, we used BEF (spontaneously immortalized bovine embryonic fibroblast that shows myogenic differentiation by overexpression of MyoD) and C2C12 cells to investigate the function of MRF4. Ectopic expressions of MRF4 did not stimulate myogenic differentiation in the BEF and C2C12 cells, but did show a marked increase of cell proliferation, upregulation of cyclin E, and downregulation of p21 WAF1 . Furthermore, MRF4 was found to induce degradation of the MyoD protein, which acts as a transcriptional activator for p21 WAF1 , and thus indicates that MRF4 accelerates cell proliferation by suppressing MyoD-dependent p21 WAF1 expression. However, forced expression of MyoD in the MRF4-overexpressing cells inhibited cell proliferation and partially induced myogenic differentiation, which suggests that MyoD is a potential negative intercessor of MRF4 in the regulation of the cell cycle. Taken together, these results indicate that MRF4 and MyoD play competitive roles in myogenesis by stimulating cell proliferation and differentiation, respectively

  6. Gene transfection mediated by polyethyleneimine-polyethylene glycol nanocarrier prevents cisplatin-induced spiral ganglion cell damage

    Directory of Open Access Journals (Sweden)

    Guan-gui Chen

    2015-01-01

    Full Text Available Polyethyleneimine-polyethylene glycol (PEI-PEG, a novel nanocarrier, has been used for transfection and gene therapy in a variety of cells. In our previous study, we successfully carried out PEI-PEG-mediated gene transfer in spiral ganglion cells. It remains unclear whether PEI-PEG could be used for gene therapy with X-linked inhibitor of apoptosis protein (XIAP in the inner ear. In the present study, we performed PEI-PEG-mediated XIAP gene transfection in the cochlea of Sprague-Dawley rats, via scala tympani fenestration, before daily cisplatin injections. Auditory brainstem reflex tests demonstrated the protective effects of XIAP gene therapy on auditory function. Immunohistochemical staining revealed XIAP protein expression in the cytoplasm of cells in the spiral ganglion, the organ of Corti and the stria vascularis. Reverse transcription-PCR detected high levels of XIAP mRNA expression in the cochlea. The present findings suggest that PEI-PEG nanocarrier-mediated XIAP gene transfection results in XIAP expression in the cochlea, prevents damage to cochlear spiral ganglion cells, and protects hearing.

  7. Synthesis of Functionalized Fluorescent Silver Nanoparticles and their toxicological effect in aquatic environments (Goldfish) and HEPG2 cells.

    Science.gov (United States)

    Santos, Hugo; Oliveira, Elisabete; Garcia-Pardo, Javier; Diniz, Mário; Lorenzo, Julia; Rodriguez-González, Benito; Capelo, José Luis; Lodeiro, Carlos

    2013-12-01

    Silver nanoparticles, AgNPs, are widely used in our daily life, mostly due to their antibacterial, antiviral and antifungal properties. However, their potential toxicity remains unclear. In order to unravel this issue, emissive AgNPs were first synthetized using an inexpensive photochemical method, and then their permeation was assessed in vivo in goldfish and in vitro in human hepatoma cells (HepG2). In addition, the oxidative stress caused by AgNPs was assessed in enzymes such as glutathione-S-transferase (GST), catalase (CAT) and in lipid peroxidation (LPO). This study demonstrates that the smallest sized AgNPs@3 promote the largest changes in gold fish livers, whereas AgNPs@1 were found to be toxic in HEPG2 cells depending on both the size and functionalized/stabilizer ligand.

  8. Synthesis of Functionalized Fluorescent Silver Nanoparticles and their toxicological effect in aquatic environments (Goldfish and HEPG2 cells.

    Directory of Open Access Journals (Sweden)

    Hugo Miguel Santos

    2013-12-01

    Full Text Available Silver nanoparticles, AgNPs, are widely used in our daily life, mostly due to their antibacterial, antiviral and antifungal properties. However, their potential toxicity remains unclear. In order to unravel this issue, emissive AgNPs were first synthetized using an inexpensive photochemical method, and then their permeation was assessed in vivo in goldfish and in vitro in human hepatoma cells (HepG2. In addition, the oxidative stress caused by AgNPs was assessed in enzymes such as glutathione-S-transferase (GST, catalase (CAT and in lipid peroxidation (LPO. This study demonstrates that the smallest sized AgNPs@3 promote the largest changes in gold fish livers, whereas AgNPs@1 were found to be toxic in HEPG2 cells depending on both the size and functionalized/stabilizer ligand.

  9. CD147 is increased in HCC cells under starvation and reduces cell death through upregulating p-mTOR in vitro.

    Science.gov (United States)

    Gou, Xingchun; Tang, Xu; Kong, Derek Kai; He, Xinying; Gao, Xingchun; Guo, Na; Hu, Zhifang; Zhao, Zhaohua; Chen, Yanke

    2016-01-01

    Transarterial chemoembolization (TACE) is the standard of care for treatment of intermediate hepatocellular carcinoma (HCC), however, key molecules involved in HCC cell survival and tumor metastasis post-TACE remain unclear. CD147 is a member of the immunoglobulin superfamily that is overexpressed on the surface of HCC cells and is associated with malignant potential and poor prognosis in HCC patients. In this study, using an Earle's Balanced Salt Solution medium culture model that mimics nutrient deprivation induced by TACE, we investigated the regulation of CD147 expression on HCC cells under starvation conditions and its functional effects on HCC cell death. During early stages of starvation, the expression of CD147 was considerably upregulated in SMMC7721, HepG2 and HCC9204 hepatoma cell lines at the protein levels. Downregulation of CD147 by specific small interfering RNA (siRNA) significantly promoted starvation-induced cell death. In addition, CD147 siRNA-transfected SMMC7721 cells demonstrated significantly increased levels of both apoptosis and autophagy as compared to cells transfected with control siRNA under starvation conditions, whereas no difference was observed between the two treatment groups under normal culture conditions. Furthermore, silencing of CD147 resulted in a remarkable downregulation of phosphorylated mammalian target of rapamycin (p-mTOR) in starved SMMC7721 cells. Finally, the combined treatment of starvation and anti-CD147 monoclonal antibody exhibited a synergistic HCC cell killing effect. Our study suggests that upregulation of CD147 under starvation may reduce hepatoma cell death by modulating both apoptosis and autophagy through mTOR signaling, and that CD147 may be a novel potential molecular target to improve the efficacy of TACE.

  10. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruoxing [Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive 5018, Hattiesburg, MS 39406 (United States); Guo, Yan-Lin, E-mail: yanlin.guo@usm.edu [Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive 5018, Hattiesburg, MS 39406 (United States)

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: Black-Right-Pointing-Pointer Inhibition of Cdks slows down mESCs proliferation. Black-Right-Pointing-Pointer mESCs display remarkable recovery capacity from short-term cell cycle interruption. Black-Right-Pointing-Pointer Short-term cell cycle interruption does not compromise mESC self-renewal. Black

  11. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Wang, Ruoxing; Guo, Yan-Lin

    2012-01-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: ► Inhibition of Cdks slows down mESCs proliferation. ► mESCs display remarkable recovery capacity from short-term cell cycle interruption. ► Short-term cell cycle interruption does not compromise mESC self-renewal. ► Oct4 and Nanog are up-regulated via de novo synthesis by cell cycle interruption.

  12. Inhibition of autophagy induced by proteasome inhibition increases cell death in human SHG-44 glioma cells.

    Science.gov (United States)

    Ge, Peng-Fei; Zhang, Ji-Zhou; Wang, Xiao-Fei; Meng, Fan-Kai; Li, Wen-Chen; Luan, Yong-Xin; Ling, Feng; Luo, Yi-Nan

    2009-07-01

    The ubiquitin-proteasome system (UPS) and lysosome-dependent macroautophagy (autophagy) are two major intracellular pathways for protein degradation. Recent studies suggest that proteasome inhibitors may reduce tumor growth and activate autophagy. Due to the dual roles of autophagy in tumor cell survival and death, the effect of autophagy on the destiny of glioma cells remains unclear. In this study, we sought to investigate whether inhibition of the proteasome can induce autophagy and the effects of autophagy on the fate of human SHG-44 glioma cells. The proteasome inhibitor MG-132 was used to induce autophagy in SHG-44 glioma cells, and the effect of autophagy on the survival of SHG-44 glioma cells was investigated using an autophagy inhibitor 3-MA. Cell viability was measured by MTT assay. Apoptosis and cell cycle were detected by flow cytometry. The expression of autophagy related proteins was determined by Western blot. MG-132 inhibited cell proliferation, induced cell death and cell cycle arrest at G(2)/M phase, and activated autophagy in SHG-44 glioma cells. The expression of autophagy-related Beclin-1 and LC3-I was significantly up-regulated and part of LC3-I was converted into LC3-II. However, when SHG-44 glioma cells were co-treated with MG-132 and 3-MA, the cells became less viable, but cell death and cell numbers at G(2)/M phase increased. Moreover, the accumulation of acidic vesicular organelles was decreased, the expression of Beclin-1 and LC3 was significantly down-regulated and the conversion of LC3-II from LC3-I was also inhibited. Inhibition of the proteasome can induce autophagy in human SHG-44 glioma cells, and inhibition of autophagy increases cell death. This discovery may shed new light on the effect of autophagy on modulating the fate of SHG-44 glioma cells.Acta Pharmacologica Sinica (2009) 30: 1046-1052; doi: 10.1038/aps.2009.71.

  13. β-adrenergic relaxation of smooth muscle: differences between cells and tissues

    International Nuclear Information System (INIS)

    Scheid, C.R.

    1987-01-01

    The present studies were carried out in an attempt to resolve the controversy about the Na + dependence of β-adrenergic relaxation in smooth muscle. Previous studies on isolated smooth muscle cells from the toad stomach had suggested that at least some of the actions of β-adrenergic agents, including a stimulatory effect on 45 Ca efflux, were dependent on the presence of a normal transmembrane Na + gradient. Studies by other investigators using tissues derived from mammalian sources had suggested that the relaxing effect of β-adrenergic agents was Na + independent. Uncertainty remained as to whether these discrepancies reflected differences between cells and tissues or differences between species. Thus, in the present studies, the authors utilized both tissues and cells from the same source, the stomach muscle of the toad Bufo marinus, and assessed the Na + dependence of β-adrenergic relaxation. They found that elimination of a normal Na + gradient abolished β-adrenergic relaxation of isolated cells. In tissues, however, similar manipulations had no effect on relaxation. The reasons for this discrepancy are unclear but do not appear to be attributable to changes in smooth muscle function following enzymatic dispersion. Thus the controversy concerning the mechanisms of β-adrenergic relaxation may reflect inherent differences between tissues and cells

  14. The c-Myc target glycoprotein1balpha links cytokinesis failure to oncogenic signal transduction pathways in cultured human cells.

    Directory of Open Access Journals (Sweden)

    Qian Wu

    2010-05-01

    Full Text Available An increase in chromosome number, or polyploidization, is associated with a variety of biological changes including breeding of cereal crops and flowers, terminal differentiation of specialized cells such as megakaryocytes, cellular stress and oncogenic transformation. Yet it remains unclear how cells tolerate the major changes in gene expression, chromatin organization and chromosome segregation that invariably accompany polyploidization. We show here that cancer cells can initiate increases in chromosome number by inhibiting cell division through activation of glycoprotein1b alpha (GpIbalpha, a component of the c-Myc signaling pathway. We are able to recapitulate cytokinesis failure in primary cells by overexpression of GpIbalpha in a p53-deficient background. GpIbalpha was found to localize to the cleavage furrow by microscopy analysis and, when overexpressed, to interfere with assembly of the cellular cortical contraction apparatus and normal division. These results indicate that cytokinesis failure and tetraploidy in cancer cells are directly linked to cellular hyperproliferation via c-Myc induced overexpression of GpIbalpha.

  15. Hypomethylation of the Treg-Specific Demethylated Region in FOXP3 Is a Hallmark of the Regulatory T-cell Subtype in Adult T-cell Leukemia.

    Science.gov (United States)

    Shimazu, Yayoi; Shimazu, Yutaka; Hishizawa, Masakatsu; Hamaguchi, Masahide; Nagai, Yuya; Sugino, Noriko; Fujii, Sumie; Kawahara, Masahiro; Kadowaki, Norimitsu; Nishikawa, Hiroyoshi; Sakaguchi, Shimon; Takaori-Kondo, Akifumi

    2016-02-01

    Adult T-cell leukemia (ATL) is an aggressive T-cell malignancy caused by human T-cell leukemia virus type 1. Because of its immunosuppressive property and resistance to treatment, patients with ATL have poor prognoses. ATL cells possess the regulatory T cell (Treg) phenotype, such as CD4 and CD25, and usually express forkhead box P3 (FOXP3). However, the mechanisms of FOXP3 expression and its association with Treg-like characteristics in ATL remain unclear. Selective demethylation of the Treg-specific demethylated region (TSDR) in the FOXP3 gene leads to stable FOXP3 expression and defines natural Tregs. Here, we focus on the functional and clinical relationship between the epigenetic pattern of the TSDR and ATL. Analysis of DNA methylation in specimens from 26 patients with ATL showed that 15 patients (58%) hypomethylated the TSDR. The FOXP3(+) cells were mainly observed in the TSDR-hypomethylated cases. The TSDR-hypomethylated ATL cells exerted more suppressive function than the TSDR-methylated ATL cells. Thus, the epigenetic analysis of the FOXP3 gene identified a distinct subtype with Treg properties in heterogeneous ATL. Furthermore, we observed that the hypomethylation of TSDR was associated with poor outcomes in ATL. These results suggest that the DNA methylation status of the TSDR is an important hallmark to define this heterogeneous disease and to predict ATL patient prognosis. ©2015 American Association for Cancer Research.

  16. Enhanced tumor growth in the remaining lung after major lung resection.

    Science.gov (United States)

    Sano, Fumiho; Ueda, Kazuhiro; Murakami, Junichi; Hayashi, Masataro; Nishimoto, Arata; Hamano, Kimikazu

    2016-05-01

    Pneumonectomy induces active growth of the remaining lung in order to compensate for lost lung tissue. We hypothesized that tumor progression is enhanced in the activated local environment. We examined the effects of mechanical strain on the activation of lung growth and tumor progression in mice. The mechanical strain imposed on the right lung after left pneumonectomy was neutralized by filling the empty space that remained after pneumonectomy with a polypropylene prosthesis. The neutralization of the strain prevented active lung growth. According to an angiogenesis array, stronger monocyte chemoattractant protein-1 (MCP-1) expression was found in the strain-induced growing lung. The neutralization of the strain attenuated the release of MCP-1 from the lung cells. The intravenous injection of Lewis lung cancer cells resulted in the enhanced development of metastatic foci in the strain-induced growing lung, but the enhanced development was canceled by the neutralization of the strain. An immunohistochemical analysis revealed the prominent accumulation of tumor-associated macrophages in tumors arising in the strain-induced growing lung, and that there was a relationship between the accumulation and the MCP-1 expression status. Our results suggested that mechanical lung strain, induced by pulmonary resection, triggers active lung growth, thereby creating a tumor-friendly environment. The modification of that environment, as well as the minimizing of surgical stress, may be a meaningful strategy to improve the therapeutic outcome after lung cancer surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Mechanical regulation of stem-cell differentiation by the stretch-activated Piezo channel.

    Science.gov (United States)

    He, Li; Si, Guangwei; Huang, Jiuhong; Samuel, Aravinthan D T; Perrimon, Norbert

    2018-03-01

    Somatic stem cells constantly adjust their self-renewal and lineage commitment by integrating various environmental cues to maintain tissue homeostasis. Although numerous chemical and biological signals have been identified that regulate stem-cell behaviour, whether stem cells can directly sense mechanical signals in vivo remains unclear. Here we show that mechanical stress regulates stem-cell differentiation in the adult Drosophila midgut through the stretch-activated ion channel Piezo. We find that Piezo is specifically expressed in previously unidentified enteroendocrine precursor cells, which have reduced proliferation ability and are destined to become enteroendocrine cells. Loss of Piezo activity reduces the generation of enteroendocrine cells in the adult midgut. In addition, ectopic expression of Piezo in all stem cells triggers both cell proliferation and enteroendocrine cell differentiation. Both the Piezo mutant and overexpression phenotypes can be rescued by manipulation of cytosolic Ca 2+ levels, and increases in cytosolic Ca 2+ resemble the Piezo overexpression phenotype, suggesting that Piezo functions through Ca 2+ signalling. Further studies suggest that Ca 2+ signalling promotes stem-cell proliferation and differentiation through separate pathways. Finally, Piezo is required for both mechanical activation of stem cells in a gut expansion assay and the increase of cytosolic Ca 2+ in response to direct mechanical stimulus in a gut compression assay. Thus, our study demonstrates the existence of a specific group of stem cells in the fly midgut that can directly sense mechanical signals through Piezo.

  18. Breaking down pluripotency in the porcine embryo reveals both a premature and reticent stem cell state in the inner cell mass and unique expression profiles of the naive and primed stem cell states.

    Science.gov (United States)

    Hall, Vanessa Jane; Hyttel, Poul

    2014-09-01

    To date, it has been difficult to establish bona fide porcine embryonic stem cells (pESC) and stable induced pluripotent stem cells. Reasons for this remain unclear, but they may depend on inappropriate culture conditions. This study reports the most insights to date on genes expressed in the pluripotent cells of the porcine embryo, namely the inner cell mass (ICM), the trophectoderm-covered epiblast (EPI), and the embryonic disc epiblast (ED). Specifically, we reveal that the early porcine ICM represents a premature state of pluripotency due to lack of translation of key pluripotent proteins, and the late ICM enters a transient, reticent pluripotent state which lacks expression of most genes associated with pluripotency. We describe a unique expression profile of the porcine EPI, reflecting the naive stem cell state, including expression of OCT4, NANOG, CRIPTO, and SSEA-1; weak expression of NrOB1 and REX1; but very limited expression of genes in classical pathways involved in regulating pluripotency. The porcine ED, reflecting the primed stem cell state, can be characterized by the expression of OCT4, NANOG, SOX2, KLF4, cMYC, REX1, CRIPTO, and KLF2. Further cell culture experiments using inhibitors against FGF, JAK/STAT, BMP, WNT, and NODAL pathways on cell cultures derived from day 5 and 10 embryos reveal the importance of FGF, JAK/STAT, and BMP signaling in maintaining cell proliferation of pESCs in vitro. Together, this article provides new insights into the regulation of pluripotency, revealing unique stem cell states in the different porcine stem cell populations derived from the early developing embryo.

  19. Androgen action via testicular arteriole smooth muscle cells is important for Leydig cell function, vasomotion and testicular fluid dynamics.

    Directory of Open Access Journals (Sweden)

    Michelle Welsh

    2010-10-01

    Full Text Available Regulation of blood flow through the testicular microvasculature by vasomotion is thought to be important for normal testis function as it regulates interstitial fluid (IF dynamics which is an important intra-testicular transport medium. Androgens control vasomotion, but how they exert these effects remains unclear. One possibility is by signalling via androgen receptors (AR expressed in testicular arteriole smooth muscle cells. To investigate this and determine the overall importance of this mechanism in testis function, we generated a blood vessel smooth muscle cell-specific AR knockout mouse (SMARKO. Gross reproductive development was normal in SMARKO mice but testis weight was reduced in adulthood compared to control littermates; this reduction was not due to any changes in germ cell volume or to deficits in testosterone, LH or FSH concentrations and did not cause infertility. However, seminiferous tubule lumen volume was reduced in adult SMARKO males while interstitial volume was increased, perhaps indicating altered fluid dynamics; this was associated with compensated Leydig cell failure. Vasomotion was impaired in adult SMARKO males, though overall testis blood flow was normal and there was an increase in the overall blood vessel volume per testis in adult SMARKOs. In conclusion, these results indicate that ablating arteriole smooth muscle AR does not grossly alter spermatogenesis or affect male fertility but does subtly impair Leydig cell function and testicular fluid exchange, possibly by locally regulating microvascular blood flow within the testis.

  20. Human cytomegalovirus-induced NKG2C(hi) CD57(hi) natural killer cells are effectors dependent on humoral antiviral immunity.

    Science.gov (United States)

    Wu, Zeguang; Sinzger, Christian; Frascaroli, Giada; Reichel, Johanna; Bayer, Carina; Wang, Li; Schirmbeck, Reinhold; Mertens, Thomas

    2013-07-01

    Recent studies indicate that expansion of NKG2C-positive natural killer (NK) cells is associated with human cytomegalovirus (HCMV); however, their activity in response to HCMV-infected cells remains unclear. We show that NKG2C(hi) CD57(hi) NK cells gated on CD3(neg) CD56(dim) cells can be phenotypically identified as HCMV-induced NK cells that can be activated by HCMV-infected cells. Using HCMV-infected autologous macrophages as targets, we were able to show that these NKG2C(hi) CD57(hi) NK cells are highly responsive to HCMV-infected macrophages only in the presence of HCMV-specific antibodies, whereas they are functionally poor effectors of natural cytotoxicity. We further demonstrate that NKG2C(hi) CD57(hi) NK cells are intrinsically responsive to signaling through CD16 cross-linking. Our findings show that the activity of pathogen-induced innate immune cells can be enhanced by adaptive humoral immunity. Understanding the activity of NKG2C(hi) CD57(hi) NK cells against HCMV-infected cells will be of relevance for the further development of adoptive immunotherapy.

  1. Control of cell behavior on PTFE surface using ion beam irradiation

    International Nuclear Information System (INIS)

    Kitamura, Akane; Kobayashi, Tomohiro; Meguro, Takashi; Suzuki, Akihiro; Terai, Takayuki

    2009-01-01

    A polytetrafluoroethylene (PTFE) surface is smooth and biologically inert, so that cells cannot attach to it. Ion beam irradiation of the PTFE surface forms micropores and a melted layer, and the surface is finally covered with a large number of small protrusions. Recently, we found that cells could adhere to this irradiated PTFE surface and spread over the surface. Because of their peculiar attachment behavior, these surfaces can be used as biological tools. However, the factors regulating cell adhesion are still unclear, although some new functional groups formed by irradiation seem to contribute to this adhesion. To control cell behavior on PTFE surfaces, we must determine the effects of the outermost irradiated surface on cell adhesion. In this study, we removed the thin melted surface layer by postirradiation annealing and investigated cell behavior on the surface. On the surface irradiated with 3 x 10 16 ions/cm 2 , cells spread only on the remaining parts of the melted layer. From these results, it is clear that the melted layer had a capacity for cell attachment. When the surface covered with protrusions was irradiated with a fluence of 1 x 10 17 ions/cm 2 , the distribution of cells changed after the annealing process from 'sheet shaped' into multicellular aggregates with diameters of around 50 μm. These results indicate that we can control cell behavior on PTFE surfaces covered with protrusions using irradiation and subsequent annealing. Multicellular spheroids can be fabricated for tissue engineering using this surface.

  2. U6 snRNA expression prevents toxicity in TDP-43-knockdown cells.

    Directory of Open Access Journals (Sweden)

    Masao Yahara

    Full Text Available Depletion of amyotrophic lateral sclerosis (ALS-associated transactivation response (TAR RNA/DNA-binding protein 43 kDa (TDP-43 alters splicing efficiency of multiple transcripts and results in neuronal cell death. TDP-43 depletion can also disturb expression levels of small nuclear RNAs (snRNAs as spliceosomal components. Despite this knowledge, the relationship between cell death and alteration of snRNA expression during TDP-43 depletion remains unclear. Here, we knocked down TDP-43 in murine neuroblastoma Neuro2A cells and found a time lag between efficient TDP-43 depletion and appearance of cell death, suggesting that several mechanisms mediate between these two events. The amount of U6 snRNA was significantly decreased during TDP-43 depletion prior to increase of cell death, whereas that of U1, U2, and U4 snRNAs was not. Downregulation of U6 snRNA led to cell death, whereas transient exogenous expression of U6 snRNA counteracted the effect of TDP-43 knockdown on cell death, and slightly decreased the mis-splicing rate of Dnajc5 and Sortilin 1 transcripts, which are assisted by TDP-43. These results suggest that regulation of the U6 snRNA expression level by TDP-43 is a key factor in the increase in cell death upon TDP-43 loss-of-function.

  3. Melatonin prevents human pancreatic carcinoma cell PANC-1-induced human umbilical vein endothelial cell proliferation and migration by inhibiting vascular endothelial growth factor expression.

    Science.gov (United States)

    Cui, Peilin; Yu, Minghua; Peng, Xingchun; Dong, Lv; Yang, Zhaoxu

    2012-03-01

    Melatonin is an important natural oncostatic agent, and our previous studies have found its inhibitory action on tumor angiogenesis, but the mechanism remains unclear. It is well known that vascular endothelial growth factor (VEGF) plays key roles in tumor angiogenesis and has become an important target for antitumor therapy. Pancreatic cancer is a representative of the most highly vascularized and angiogenic solid tumors, which responds poorly to chemotherapy and radiation. Thus, seeking new treatment strategies targeting which have anti-angiogenic capability is urgent in clinical practice. In this study, a co-culture system between human umbilical vein endothelial cells (HUVECs) and pancreatic carcinoma cells (PANC-1) was used to investigate the direct effect of melatonin on the tumor angiogenesis and its possible action on VEGF expression. We found HUVECs exhibited an increased cell proliferation and cell migration when co-cultured with PANC-1 cells, but the process was prevented when melatonin added to the incubation medium. Melatonin at concentrations of 1 μm and 1 mm inhibited the cell proliferation and migration of HUVECs and also decreased both the VEGF protein secreted to the cultured medium and the protein produced by the PANC-1 cells. In addition, the VEGF mRNA expression was also down-regulated by melatonin. Taken together, our present study shows that melatonin at pharmacological concentrations inhibited the elevated cell proliferation and cell migration of HUVECs stimulated by co-culturing them with PANC-1 cells; this was associated with a suppression of VEGF expression in PANC-1 cells. © 2011 John Wiley & Sons A/S.

  4. Long-term load duration induces N-cadherin down-regulation and loss of cell phenotype of nucleus pulposus cells in a disc bioreactor culture.

    Science.gov (United States)

    Li, Pei; Zhang, Ruijie; Wang, Liyuan; Gan, Yibo; Xu, Yuan; Song, Lei; Luo, Lei; Zhao, Chen; Zhang, Chengmin; Ouyang, Bin; Tu, Bing; Zhou, Qiang

    2017-04-30

    Long-term exposure to a mechanical load causes degenerative changes in the disc nucleus pulposus (NP) tissue. A previous study demonstrated that N-cadherin (N-CDH)-mediated signalling can preserve the NP cell phenotype. However, N-CDH expression and the resulting phenotype alteration in NP cells under mechanical compression remain unclear. The present study investigated the effects of the compressive duration on N-CDH expression and on the phenotype of NP cells in an ex vivo disc organ culture. Porcine discs were organ cultured in a self-developed mechanically active bioreactor for 7 days. The discs were subjected to different dynamic compression durations (1 and 8 h at a magnitude of 0.4 MPa and frequency of 1.0 Hz) once per day. Discs that were not compressed were used as controls. The results showed that long-term compression duration (8 h) significantly down-regulated the expression of N-CDH and NP-specific molecule markers (Brachyury, Laminin, Glypican-3 and Keratin 19), attenuated Alcian Blue staining intensity, decreased glycosaminoglycan (GAG) and hydroxyproline (HYP) contents and decreased matrix macromolecule (aggrecan and collagen II) expression compared with the short-term compression duration (1 h). Taken together, these findings demonstrate that long-term load duration can induce N-CDH down-regulation, loss of normal cell phenotype and result in attenuation of NP-related matrix synthesis in NP cells. © 2017 The Author(s).

  5. Microbiota promote secretory cell determination in the intestinal epithelium by modulating host Notch signaling.

    Science.gov (United States)

    Troll, Joshua V; Hamilton, M Kristina; Abel, Melissa L; Ganz, Julia; Bates, Jennifer M; Stephens, W Zac; Melancon, Ellie; van der Vaart, Michiel; Meijer, Annemarie H; Distel, Martin; Eisen, Judith S; Guillemin, Karen

    2018-02-23

    Resident microbes promote many aspects of host development, although the mechanisms by which microbiota influence host tissues remain unclear. We showed previously that the microbiota is required for allocation of appropriate numbers of secretory cells in the zebrafish intestinal epithelium. Because Notch signaling is crucial for secretory fate determination, we conducted epistasis experiments to establish whether the microbiota modulates host Notch signaling. We also investigated whether innate immune signaling transduces microbiota cues via the Myd88 adaptor protein. We provide the first evidence that microbiota-induced, Myd88-dependent signaling inhibits host Notch signaling in the intestinal epithelium, thereby promoting secretory cell fate determination. These results connect microbiota activity via innate immune signaling to the Notch pathway, which also plays crucial roles in intestinal homeostasis throughout life and when impaired can result in chronic inflammation and cancer. © 2018. Published by The Company of Biologists Ltd.

  6. Tumor-secreted miR-214 induces regulatory T cells: a major link between immune evasion and tumor growth

    Science.gov (United States)

    Yin, Yuan; Cai, Xing; Chen, Xi; Liang, Hongwei; Zhang, Yujing; Li, Jing; Wang, Zuoyun; Chen, Xiulan; Zhang, Wen; Yokoyama, Seiji; Wang, Cheng; Li, Liang; Li, Limin; Hou, Dongxia; Dong, Lei; Xu, Tao; Hiroi, Takachika; Yang, Fuquan; Ji, Hongbin; Zhang, Junfeng; Zen, Ke; Zhang, Chen-Yu

    2014-01-01

    An increased population of CD4+CD25highFoxp3+ regulatory T cells (Tregs) in the tumor-associated microenvironment plays an important role in cancer immune evasion. However, the underlying mechanism remains unclear. Here we observed an increased secretion of miR-214 in various types of human cancers and mouse tumor models. Tumor-secreted miR-214 was sufficiently delivered into recipient T cells by microvesicles (MVs). In targeted mouse peripheral CD4+ T cells, tumor-derived miR-214 efficiently downregulated phosphatase and tensin homolog (PTEN) and promoted Treg expansion. The miR-214-induced Tregs secreted higher levels of IL-10 and promoted tumor growth in nude mice. Furthermore, in vivo studies indicated that Treg expansion mediated by cancer cell-secreted miR-214 resulted in enhanced immune suppression and tumor implantation/growth in mice. The MV delivery of anti-miR-214 antisense oligonucleotides (ASOs) into mice implanted with tumors blocked Treg expansion and tumor growth. Our study reveals a novel mechanism through which cancer cell actively manipulates immune response via promoting Treg expansion. PMID:25223704

  7. Schwann cell myelination requires Dynein function

    Directory of Open Access Journals (Sweden)

    Langworthy Melissa M

    2012-11-01

    Full Text Available Abstract Background Interaction of Schwann cells with axons triggers signal transduction that drives expression of Pou3f1 and Egr2 transcription factors, which in turn promote myelination. Signal transduction appears to be mediated, at least in part, by cyclic adenosine monophosphate (cAMP because elevation of cAMP levels can stimulate myelination in the absence of axon contact. The mechanisms by which the myelinating signal is conveyed remain unclear. Results By analyzing mutations that disrupt myelination in zebrafish, we learned that Dynein cytoplasmic 1 heavy chain 1 (Dync1h1, which functions as a motor for intracellular molecular trafficking, is required for peripheral myelination. In dync1h1 mutants, Schwann cell progenitors migrated to peripheral nerves but then failed to express Pou3f1 and Egr2 or make myelin membrane. Genetic mosaic experiments revealed that robust Myelin Basic Protein expression required Dync1h1 function within both Schwann cells and axons. Finally, treatment of dync1h1 mutants with a drug to elevate cAMP levels stimulated myelin gene expression. Conclusion Dync1h1 is required for retrograde transport in axons and mutations of Dync1h1 have been implicated in axon disease. Our data now provide evidence that Dync1h1 is also required for efficient myelination of peripheral axons by Schwann cells, perhaps by facilitating signal transduction necessary for myelination.

  8. Quantitative analysis of rat adipose tissue cell recovery, and non-fat cell volume, in primary cell cultures

    Directory of Open Access Journals (Sweden)

    Floriana Rotondo

    2016-11-01

    Full Text Available Background White adipose tissue (WAT is a complex, diffuse, multifunctional organ which contains adipocytes, and a large proportion of fat, but also other cell types, active in defense, regeneration and signalling functions. Studies with adipocytes often require their isolation from WAT by breaking up the matrix of collagen fibres; however, it is unclear to what extent adipocyte number in primary cultures correlates with their number in intact WAT, since recovery and viability are often unknown. Experimental Design Epididymal WAT of four young adult rats was used to isolate adipocytes with collagenase. Careful recording of lipid content of tissue, and all fraction volumes and weights, allowed us to trace the amount of initial WAT fat remaining in the cell preparation. Functionality was estimated by incubation with glucose and measurement of glucose uptake and lactate, glycerol and NEFA excretion rates up to 48 h. Non-adipocyte cells were also recovered and their sizes (and those of adipocytes were measured. The presence of non-nucleated cells (erythrocytes was also estimated. Results Cell numbers and sizes were correlated from all fractions to intact WAT. Tracing the lipid content, the recovery of adipocytes in the final, metabolically active, preparation was in the range of 70–75%. Cells showed even higher metabolic activity in the second than in the first day of incubation. Adipocytes were 7%, erythrocytes 66% and other stromal (nucleated cells 27% of total WAT cells. However, their overall volumes were 90%, 0.05%, and 0.2% of WAT. Non-fat volume of adipocytes was 1.3% of WAT. Conclusions The methodology presented here allows for a direct quantitative reference to the original tissue of studies using isolated cells. We have also found that the “live cell mass” of adipose tissue is very small: about 13 µL/g for adipocytes and 2 µL/g stromal, plus about 1 µL/g blood (the rats were killed by exsanguination. These data translate (with

  9. Persistent response of Fanconi anemia haematopoietic stem and progenitor cells to oxidative stress.

    Science.gov (United States)

    Li, Yibo; Amarachintha, Surya; Wilson, Andrew F; Li, Xue; Du, Wei

    2017-06-18

    Oxidative stress is considered as an important pathogenic factor in many human diseases including Fanconi anemia (FA), an inherited bone marrow failure syndrome with extremely high risk of leukemic transformation. Members of the FA protein family are involved in DNA damage and other cellular stress responses. Loss of FA proteins renders cells hypersensitive to oxidative stress and cancer transformation. However, how FA cells respond to oxidative DNA damage remains unclear. By using an in vivo stress-response mouse strain expressing the Gadd45β-luciferase transgene, we show here that haematopoietic stem and progenitor cells (HSPCs) from mice deficient for the FA gene Fanca or Fancc persistently responded to oxidative stress. Mechanistically, we demonstrated that accumulation of unrepaired DNA damage, particularly in oxidative damage-sensitive genes, was responsible for the long-lasting response in FA HSPCs. Furthermore, genetic correction of Fanca deficiency almost completely abolished the persistent oxidative stress-induced G 2 /M arrest and DNA damage response in vivo. Our study suggests that FA pathway is an integral part of a versatile cellular mechanism by which HSPCs respond to oxidative stress.

  10. Proliferation and osteo/odontogenic differentiation of stem cells from apical papilla regulated by Zinc fingers and homeoboxes 2: An in vitro study.

    Science.gov (United States)

    Wan, Fang; Gao, Lifen; Lu, Yating; Ma, Hongxin; Wang, Hongxing; Liang, Xiaohong; Wang, Yan; Ma, Chunhong

    2016-01-15

    In the process of tooth root development, stem cells from the apical papilla (SCAPs) can differentiate into odontoblasts and form root dentin, however, molecules regulating SCAPs differentiation have not been elucidated. Zinc fingers and homeoboxes 2 (ZHX2) is a novel transcriptional inhibitor. It is reported to modulate the development of nerve cells, liver cells, B cells, red blood cells, and so on. However, the role of ZHX2 in tooth root development remains unclear. In this study, we explored the potential role of ZHX2 in the process of SCAPs differentiation. The results showed that overexpression of ZHX2 upregulated the expression of osteo/odontogenic related genes and ALP activity, inhibited the proliferation of SCAPs. Consistently, ZHX2 knockdown reduced SCAPs mineralization and promoted SCAPs proliferation. These results indicated that ZHX2 plays a critical role in the proliferation and osteo/odontogenic differentiation of SCAPs. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Reduced expression levels of PTEN are associated with decreased sensitivity of HCC827 cells to icotinib.

    Science.gov (United States)

    Zhai, Yang; Zhang, Yanjun; Nan, Kejun; Liang, Xuan

    2017-05-01

    The clinical resistance of non-small cell lung cancer (NSCLC) to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) has been linked to EGFR T790M resistance mutations or MET amplifications. Additional mechanisms underlying EGFR-TKI drug resistance remain unclear. The present study demonstrated that icotinib significantly inhibited the proliferation and increased the apoptosis rate of HCC827 cells; the cellular mRNA and protein expression levels of phosphatase and tensin homolog (PTEN) were also significantly downregulated. To investigate the effect of PTEN expression levels on the sensitivity of HCC827 cells to icotinib, PTEN expression was silenced using a PTEN-specific small interfering RNA. The current study identified that the downregulation of PTEN expression levels may promote cellular proliferation in addition to decreasing the apoptosis of HCC827 cells, and may reduce the sensitivity of HCC827 cells to icotinib. These results suggested that reduced PTEN expression levels were associated with the decreased sensitivity of HCC827 cells to icotinib. Furthermore, PTEN expression levels may be a useful marker for predicting icotinib resistance and elucidating the resistance mechanisms underlying EGFR-mutated NSCLC.

  12. [PALEOPATHOLOGY OF HUMAN REMAINS].

    Science.gov (United States)

    Minozzi, Simona; Fornaciari, Gino

    2015-01-01

    Many diseases induce alterations in the human skeleton, leaving traces of their presence in ancient remains. Paleopathological examination of human remains not only allows the study of the history and evolution of the disease, but also the reconstruction of health conditions in the past populations. This paper describes the most interesting diseases observed in skeletal samples from the Roman Imperial Age necropoles found in urban and suburban areas of Rome during archaeological excavations in the last decades. The diseases observed were grouped into the following categories: articular diseases, traumas, infections, metabolic or nutritional diseases, congenital diseases and tumours, and some examples are reported for each group. Although extensive epidemiological investigation in ancient skeletal records is impossible, the palaeopathological study allowed to highlight the spread of numerous illnesses, many of which can be related to the life and health conditions of the Roman population.

  13. Methadone induces CAD degradation and AIF-mediated necrotic-like cell death in neuroblastoma cells.

    Science.gov (United States)

    Perez-Alvarez, Sergio; Iglesias-Guimarais, Victoria; Solesio, María E; Melero-Fernandez de Mera, Raquel María; Yuste, Víctor J; Galindo, María F; Jordán, Joaquín

    2011-04-01

    Methadone (d,l-methadone hydrochloride) is a full-opioid agonist, originally developed as a substitution for heroin or other opiates abusers. Nowadays methadone is also being applied as long-lasting analgesics in cancer, and it is proposed as a promising agent for leukemia therapy. Previously, we have demonstrated that high concentrations of methadone (0.5mM) induced necrotic-like cell death in SH-SY5Y cells. The pathway involved is caspase-independent but involves impairment of mitochondrial ATP synthesis and mitochondrial cytochrome c release. However, the downstream mitochondrial pathways remained unclear. Here, we studied the participation of apoptosis inducing factor (AIF) in methadone-induced cell death. Methadone resulted in a translocation of AIF from mitochondria to the nucleus. Translocation was inhibited by cyclosporine A, but not by lack of Bax protein. Therefore the effect seems mediated by the formation of the mitochondrial transition pore, but is apparently independent of Bax. Furthermore, methadone-treated SH-SY5Y nuclei show characteristics that are typical for stage I nuclear condensation. Methadone did not induce degradation of DNA into oligonucleosomal fragments or into high molecular weight DNA fragments. Absence of DNA fragmentation coincided with a considerable decrease in the levels of the caspase-actived endonuclase DNase and its chaperone-inhibitor ICAD. In conclusion, our results provide mechanistic insights into the molecular mechanisms that underlie methadone-induced cell death. This knowledge may prove useful to develop novel strategies to prevent toxic side-effects of methadone thereby sustaining its use as therapeutical agent against tumors. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Real-time imaging of nitric oxide production in living cells with 1,3,5,7-tetramethyl-2,6-dicarbethoxy-8-(3',4'-diaminophenyl)-difluoroboradiaza-s-indacence by invert fluorescence microscope.

    Science.gov (United States)

    Huang, Ke-Jing; Wang, Hong; Ma, Ming; Zhang, Xian; Zhang, Hua-Shan

    2007-02-01

    Although the importance of nitric oxide (NO) as a signalling molecule in many biological processes is becoming increasingly evident, many proposed and potential biological functions of NO still remain unclear. Bioimaging is a good technique to visualize observation of nitric oxide in biological samples. In this report, a fluorescent probe, 1,3,5,7-tetramethyl-2,6-dicarbethoxy-8-(3',4'-diaminophenyl)-difluoroboradiaza-s-indacence (TMDCDABODIPY), has been first applied to real-time image NO produced in PC12 cells, Sf9 cells and human vascular endothelial cells at the presence of l-arginine with inverted fluorescence microscope. NO production in the cells is successfully captured and imaged with fine temporal and spatial resolution. The results prove that the probe combined with inverted fluorescence microscope can be developed into a sensitive and selective method for further study of NO release from cells.

  15. Regulators of floral fragrance production and their target genes in petunia are not exclusively active in the epidermal cells of petals.

    Science.gov (United States)

    Van Moerkercke, Alex; Galván-Ampudia, Carlos S; Verdonk, Julian C; Haring, Michel A; Schuurink, Robert C

    2012-05-01

    In which cells of the flower volatile biosynthesis takes place is unclear. In rose and snapdragon, some enzymes of the volatile phenylpropanoid/benzenoid pathway have been shown to be present in the epidermal cells of petals. It is therefore generally believed that the production of these compounds occurs in these cells. However, whether the entire pathway is active in these cells and whether it is exclusively active in these cells remains to be proven. Cell-specific transcription factors activating these genes will determine in which cells they are expressed. In petunia, the transcription factor EMISSION OF BENZENOIDS II (EOBII) activates the ODORANT1 (ODO1) promoter and the promoter of the biosynthetic gene isoeugenol synthase (IGS). The regulator ODO1 in turn activates the promoter of the shikimate gene 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). Here the identification of a new target gene of ODO1, encoding an ABC transporter localized on the plasma membrane, PhABCG1, which is co-expressed with ODO1, is described. PhABCG1 expression is up-regulated in petals overexpressing ODO1 through activation of the PhABCG1 promoter. Interestingly, the ODO1, PhABCG1, and IGS promoters were active in petunia protoplasts originating from both epidermal and mesophyll cell layers of the petal, suggesting that the volatile phenylpropanoid/benzenoid pathway in petunia is active in these different cell types. Since volatile release occurs from epidermal cells, trafficking of (volatile) compounds between cell layers must be involved, but the exact function of PhABCG1 remains to be resolved.

  16. Fractalkine Signaling Regulates Macrophage Recruitment into the Cochlea and Promotes the Survival of Spiral Ganglion Neurons after Selective Hair Cell Lesion.

    Science.gov (United States)

    Kaur, Tejbeer; Zamani, Darius; Tong, Ling; Rubel, Edwin W; Ohlemiller, Kevin K; Hirose, Keiko; Warchol, Mark E

    2015-11-11

    Macrophages are recruited into the cochlea in response to injury caused by acoustic trauma or ototoxicity, but the nature of the interaction between macrophages and the sensory structures of the inner ear remains unclear. The present study examined the role of fractalkine signaling in regulating the injury-evoked behavior of macrophages following the selective ablation of cochlear hair cells. We used a novel transgenic mouse model in which the human diphtheria toxin receptor (huDTR) is selectively expressed under the control of Pou4f3, a hair cell-specific transcription factor. Administration of diphtheria toxin (DT) to these mice resulted in nearly complete ablation of cochlear hair cells, with no evident pathology among supporting cells, spiral ganglion neurons, or cells of the cochlear lateral wall. Hair cell death led to an increase in macrophages associated with the sensory epithelium of the cochlea. Their numbers peaked at 14 days after DT and then declined at later survival times. Increased macrophages were also observed within the spiral ganglion, but their numbers remained elevated for (at least) 56 d after DT. To investigate the role of fractalkine signaling in macrophage recruitment, we crossed huDTR mice to a mouse line that lacks expression of the fractalkine receptor (CX3CR1). Disruption of fractalkine signaling reduced macrophage recruitment into both the sensory epithelium and spiral ganglion and also resulted in diminished survival of spiral ganglion neurons after hair cell death. Our results suggest a fractalkine-mediated interaction between macrophages and the neurons of the cochlea. It is known that damage to the inner ear leads to recruitment of inflammatory cells (macrophages), but the chemical signals that initiate this recruitment and the functions of macrophages in the damaged ear are unclear. Here we show that fractalkine signaling regulates macrophage recruitment into the cochlea and also promotes the survival of cochlear afferents after

  17. Comparison of the reaction of bone-derived cells to enhanced MgCl2-salt concentrations.

    Science.gov (United States)

    Burmester, Anna; Luthringer, Bérengère; Willumeit, Regine; Feyerabend, Frank

    2014-01-01

    Magnesium-based implants exhibit various advantages such as biodegradability and potential for enhanced in vivo bone formation. However, the cellular mechanisms behind this possible osteoconductivity remain unclear. To determine whether high local magnesium concentrations can be osteoconductive and exclude other environmental factors that occur during the degradation of magnesium implants, magnesium salt (MgCl2) was used as a model system. Because cell lines are preferred targets in studies of non-degradable implant materials, we performed a comparative study of 3 osteosarcoma-derived cell lines (MG63, SaoS2 and U2OS) with primary human osteoblasts. The correlation among cell count, viability, cell size and several MgCl2 concentrations was used to examine the influence of magnesium on proliferation in vitro. Moreover, bone metabolism alterations during proliferation were investigated by analyzing the expression of genes involved in osteogenesis. It was observed that for all cell types, the cell count decreases at concentrations above 10 mM MgCl2. However, detailed analysis showed that MgCl2 has a relevant but very diverse influence on proliferation and bone metabolism, depending on the cell type. Only for primary cells was a clear stimulating effect observed. Therefore, reliable results demonstrating the osteoconductivity of magnesium implants can only be achieved with primary osteoblasts.

  18. Hepatic leukemia factor promotes resistance to cell death: Implications for therapeutics and chronotherapy

    International Nuclear Information System (INIS)

    Waters, Katrina M.; Sontag, Ryan L.; Weber, Thomas J.

    2013-01-01

    Physiological variation related to circadian rhythms and aberrant gene expression patterns are believed to modulate therapeutic efficacy, but the precise molecular determinants remain unclear. Here we examine the regulation of cell death by hepatic leukemia factor (HLF), which is an output regulator of circadian rhythms and is aberrantly expressed in human cancers, using an ectopic expression strategy in JB6 mouse epidermal cells and human keratinocytes. Ectopic HLF expression inhibited cell death in both JB6 cells and human keratinocytes, as induced by serum-starvation, tumor necrosis factor alpha and ionizing radiation. Microarray analysis indicates that HLF regulates a complex multi-gene transcriptional program encompassing upregulation of anti-apoptotic genes, downregulation of pro-apoptotic genes, and many additional changes that are consistent with an anti-death program. Collectively, our results demonstrate that ectopic expression of HLF, an established transcription factor that cycles with circadian rhythms, can recapitulate many features associated with circadian-dependent physiological variation. - Highlights: ► Circadian-dependent physiological variation impacts therapeutic efficacy. ► Hepatic leukemia factor inhibits cell death and is a candidate circadian factor. ► Hepatic leukemia factor anti-death program is conserved in murine and human cells. ► Transcriptomics indicates the anti-death program results from a systems response

  19. Hepatic leukemia factor promotes resistance to cell death: Implications for therapeutics and chronotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Waters, Katrina M. [Computational Biology and Bioinformatics, Pacific Northwest National Laboratory, Richland, WA 99354 (United States); Sontag, Ryan L. [Systems Toxicology Groups, Pacific Northwest National Laboratory, Richland, WA 99354 (United States); Weber, Thomas J., E-mail: Thomas.Weber@pnl.gov [Systems Toxicology Groups, Pacific Northwest National Laboratory, Richland, WA 99354 (United States)

    2013-04-15

    Physiological variation related to circadian rhythms and aberrant gene expression patterns are believed to modulate therapeutic efficacy, but the precise molecular determinants remain unclear. Here we examine the regulation of cell death by hepatic leukemia factor (HLF), which is an output regulator of circadian rhythms and is aberrantly expressed in human cancers, using an ectopic expression strategy in JB6 mouse epidermal cells and human keratinocytes. Ectopic HLF expression inhibited cell death in both JB6 cells and human keratinocytes, as induced by serum-starvation, tumor necrosis factor alpha and ionizing radiation. Microarray analysis indicates that HLF regulates a complex multi-gene transcriptional program encompassing upregulation of anti-apoptotic genes, downregulation of pro-apoptotic genes, and many additional changes that are consistent with an anti-death program. Collectively, our results demonstrate that ectopic expression of HLF, an established transcription factor that cycles with circadian rhythms, can recapitulate many features associated with circadian-dependent physiological variation. - Highlights: ► Circadian-dependent physiological variation impacts therapeutic efficacy. ► Hepatic leukemia factor inhibits cell death and is a candidate circadian factor. ► Hepatic leukemia factor anti-death program is conserved in murine and human cells. ► Transcriptomics indicates the anti-death program results from a systems response.

  20. Down-Regulation of Desmosomes in Cultured Cells: The Roles of PKC, Microtubules and Lysosomal/Proteasomal Degradation

    Science.gov (United States)

    McHarg, Selina; Hopkins, Gemma; Lim, Lusiana; Garrod, David

    2014-01-01

    Desmosomes are intercellular adhesive junctions of major importance for tissue integrity. To allow cell motility and migration they are down-regulated in epidermal wound healing. Electron microscopy indicates that whole desmosomes are internalised by cells in tissues, but the mechanism of down-regulation is unclear. In this paper we provide an overview of the internalisation of half-desmosomes by cultured cells induced by calcium chelation. Our results show that: (i) half desmosome internalisation is dependent on conventional PKC isoforms; (ii) microtubules transport internalised half desmosomes to the region of the centrosome by a kinesin-dependent mechanism; (iii) desmosomal proteins remain colocalised after internalisation and are not recycled to the cell surface; (iv) internalised desmosomes are degraded by the combined action of lysosomes and proteasomes. We also confirm that half desmosome internalisation is dependent upon the actin cytoskeleton. These results suggest that half desmosomes are not disassembled and recycled during or after internalisation but instead are transported to the centrosomal region where they are degraded. These findings may have significance for the down-regulation of desmosomes in wounds. PMID:25291180

  1. High Plasticity of New Granule Cells in the Aging Hippocampus

    Directory of Open Access Journals (Sweden)

    Mariela F. Trinchero

    2017-10-01

    Full Text Available Summary: During aging, the brain undergoes changes that impair cognitive capacity and circuit plasticity, including a marked decrease in production of adult-born hippocampal neurons. It is unclear whether development and integration of those new neurons are also affected by age. Here, we show that adult-born granule cells (GCs in aging mice are scarce and exhibit slow development, but they display a remarkable potential for structural plasticity. Retrovirally labeled 3-week-old GCs in middle-aged mice were small, underdeveloped, and disconnected. Neuronal development and integration were accelerated by voluntary exercise or environmental enrichment. Similar effects were observed via knockdown of Lrig1, an endogenous negative modulator of neurotrophin receptors. Consistently, blocking neurotrophin signaling by Lrig1 overexpression abolished the positive effects of exercise. These results demonstrate an unparalleled degree of plasticity in the aging brain mediated by neurotrophins, whereby new GCs remain immature until becoming rapidly recruited to the network by activity. : Trinchero et al. show that development of new granule cells born in the adult hippocampus is strongly influenced by age. In the aging hippocampus, new neurons remain immature for prolonged intervals, yet voluntary exercise triggers their rapid growth and functional synaptogenesis. This extensive structural remodeling is mediated by neurotrophins. Keywords: adult neurogenesis, dentate gyrus, functional integration, neurotrophins, synaptogenesis, exercise

  2. Epigenetic silencing of V(DJ recombination is a major determinant for selective differentiation of mucosal-associated invariant t cells from induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Yutaka Saito

    Full Text Available Mucosal-associated invariant T cells (MAITs are innate-like T cells that play a pivotal role in the host defense against infectious diseases, and are also implicated in autoimmune diseases, metabolic diseases, and cancer. Recent studies have shown that induced pluripotent stem cells (iPSCs derived from MAITs selectively redifferentiate into MAITs without altering their antigen specificity. Such a selective differentiation is a prerequisite for the use of MAITs in cell therapy and/or regenerative medicine. However, the molecular mechanisms underlying this phenomenon remain unclear. Here, we performed methylome and transcriptome analyses of MAITs during the course of differentiation from iPSCs. Our multi-omics analyses revealed that recombination-activating genes (RAG1 and RAG2 and DNA nucleotidylexotransferase (DNTT were highly methylated with their expression being repressed throughout differentiation. Since these genes are essential for V(DJ recombination of the T cell receptor (TCR locus, this indicates that nascent MAITs are kept from further rearrangement that may alter their antigen specificity. Importantly, we found that the repression of RAGs was assured in two layers: one by the modulation of transcription factors for RAGs, and the other by DNA methylation at the RAG loci. Together, our study provides a possible explanation for the unaltered antigen specificity in the selective differentiation of MAITs from iPSCs.

  3. Spermidine-Activated Satellite Cells Are Associated with Hypoacetylation in ACVR2B and Smad3 Binding to Myogenic Genes in Mice.

    Science.gov (United States)

    Zhang, Luchu; Gong, Huiying; Sun, Qinwei; Zhao, Ruqian; Jia, Yimin

    2018-01-17

    Spermidine is an acetyltransferase inhibitor and a specific inducer of autophagy. Recently, spermidine is identified as a potential therapeutic agent for age-related muscle atrophy and inherited myopathies. However, the effect of spermidine on nonpathological skeletal muscle remains unclear. In this study, long-term spermidine administration in mice lowered the mean cross-sectional area of the gastrocnemius muscle and reduced the expression of myosin heavy chain isoforms in the muscle, which was associated with ubiquitination. Moreover, spermidine supplementation induced autophagy in satellite cells and enhanced satellite cell proliferation. ChIP assay revealed that spermidine repressed H3K56ac in the promoter of ACVR2B and lowered the binding affinity of Smad3 to the promoters of Myf5 and MyoD. Altogether, our results indicate that long-term administration of spermidine can activate satellite cells, as well as enhance autophagy, eventually resulting in muscle atrophy. In addition, H3K56ac and Smad3 emerged as key determinants of satellite cell activation.

  4. Atractylenolide I-mediated Notch pathway inhibition attenuates gastric cancer stem cell traits

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Li; Mao, Rurong; Shen, Ke; Zheng, Yuanhong; Li, Yueqi [State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, #268, 130 Meilong Road, Shanghai 200237 (China); Liu, Jianwen, E-mail: liujian@ecust.edu.cn [State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, #268, 130 Meilong Road, Shanghai 200237 (China); Ni, Lei, E-mail: nilei625@yahoo.com [Department of Respiration, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Road II, Shanghai 200025 (China)

    2014-07-18

    Highlights: • This paper supports the anti-tumor effects of AT-I on gastric cancer in vitro. • AT-I attenuates gastric cancer stem cell traits. • It is the systematic study regarding AT-I suppression of Notch pathway in GC and GCSLCs. - Abstract: Atractylenolide I (AT-I), one of the main naturally occurring compounds of Rhizoma Atractylodis Macrocephalae, has remarkable anti-cancer effects on various cancers. However, its effects on the treatment of gastric cancer remain unclear. Via multiple cellular and molecular approaches, we demonstrated that AT-I could potently inhibit cancer cell proliferation and induce apoptosis through inactivating Notch pathway. AT-I treatment led to the reduction of expressions of Notch1, Jagged1, and its downstream Hes1/ Hey1. Our results showed that AT-I inhibited the self-renewal capacity of gastric stem-like cells (GCSLCs) by suppression of their sphere formation capacity and cell viability. AT-I attenuated gastric cancer stem cell (GCSC) traits partly through inactivating Notch1, leading to reducing the expressions of its downstream target Hes1, Hey1 and CD44 in vitro. Collectively, our results suggest that AT-I might develop as a potential therapeutic drug for the treatment of gastric cancer.

  5. Atractylenolide I-mediated Notch pathway inhibition attenuates gastric cancer stem cell traits

    International Nuclear Information System (INIS)

    Ma, Li; Mao, Rurong; Shen, Ke; Zheng, Yuanhong; Li, Yueqi; Liu, Jianwen; Ni, Lei

    2014-01-01

    Highlights: • This paper supports the anti-tumor effects of AT-I on gastric cancer in vitro. • AT-I attenuates gastric cancer stem cell traits. • It is the systematic study regarding AT-I suppression of Notch pathway in GC and GCSLCs. - Abstract: Atractylenolide I (AT-I), one of the main naturally occurring compounds of Rhizoma Atractylodis Macrocephalae, has remarkable anti-cancer effects on various cancers. However, its effects on the treatment of gastric cancer remain unclear. Via multiple cellular and molecular approaches, we demonstrated that AT-I could potently inhibit cancer cell proliferation and induce apoptosis through inactivating Notch pathway. AT-I treatment led to the reduction of expressions of Notch1, Jagged1, and its downstream Hes1/ Hey1. Our results showed that AT-I inhibited the self-renewal capacity of gastric stem-like cells (GCSLCs) by suppression of their sphere formation capacity and cell viability. AT-I attenuated gastric cancer stem cell (GCSC) traits partly through inactivating Notch1, leading to reducing the expressions of its downstream target Hes1, Hey1 and CD44 in vitro. Collectively, our results suggest that AT-I might develop as a potential therapeutic drug for the treatment of gastric cancer

  6. Therapy-related AML/MDS after treatment of low-grade B-cell lymphoma

    International Nuclear Information System (INIS)

    Yanada, Masamitsu

    2008-01-01

    Described is the therapy-related AML (acute myelogenetic leukemia)/MDS (myelo-dysplasia syndrome), which is manifested after various treatments of low-grade B-cell lymphoma and has strongly attracted attention because of the markedly improved prognosis due to recent advantages of the therapy for the disease. AML/MDS occurs several years after chemotherapy and/or radiation therapy which cause DNA damage in hematopoietic cells, and the AML/MDS risk is known increased in patients undergone especially with autologous transplantation of those cells. AML/MDS has the feature similar to that caused either by alkylating agent or by topoisomerase-2 inhibitor, and the disease by radiation belong to the former. Yet unclear is the problem whether malignant cells causing the disease after therapy are derived from the remaining cells in the graft or in the body. Although irradiations of total body and total lymphaden as well as chemotherapy are said to be related to AML/MDS and local irradiation does not contribute to its risk, the most important factor for the disease is considered to be the autotransplantation as the recurrence occurs in 50% after it. Thus the treatment history should be taken into consideration for suppressing AML/MDS, for which follow up with consideration for the disease is required particularly after autotransplantation. (R.T.)

  7. Cells deficient in PARP-1 show an accelerated accumulation of DNA single strand breaks, but not AP sites, over the PARP-1-proficient cells exposed to MMS

    Energy Technology Data Exchange (ETDEWEB)

    Pachkowski, Brian F. [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC (United States); Tano, Keizo [Research Reactor Institute, Kyoto University, Kumatori (Japan); Afonin, Valeriy [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC (United States); Elder, Rhoderick H. [School of Environment and Life Sciences, University of Salford, Greater Manchester (United Kingdom); Takeda, Shunichi [Department of Radiation Genetics, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Watanabe, Masami [Research Reactor Institute, Kyoto University, Kumatori (Japan); Swenberg, James A. [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC (United States); Nakamura, Jun, E-mail: ynakamur@email.unc.edu [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC (United States)

    2009-12-01

    Poly(ADP-ribose) polymerase-1 (PARP-1) is a base excision repair (BER) protein that binds to DNA single strand breaks (SSBs) and subsequently synthesizes and transfers poly(ADP-ribose) polymers to various nuclear proteins. Numerous biochemical studies have implicated PARP-1 as a modulator of BER; however, the role of PARP-1 in BER in living cells remains unclear partly due to lack of accurate quantitation of BER intermediates existing in cells. Since DT40 cells, chicken B lymphocytes, naturally lack PARP-2, DT40 cells allow for the investigation of the PARP-1 null phenotype without confounding by PARP-2. To test the hypothesis that PARP-1 is necessary for efficient BER during methylmethane sulfonate (MMS) exposure in vertebrate cells, intact DT40 cells and their isogenic PARP-1 null counterparts were challenged with different exposure scenarios for phenotypic characterization. With chronic exposure, PARP-1 null cells exhibited sensitivity to MMS but with an acute exposure did not accumulate base lesions or AP sites to a greater extent than wild-type cells. However, an increase in SSB content in PARP-1 null cell DNA, as indicated by glyoxal gel electrophoresis under neutral conditions, suggested the presence of BER intermediates. These data suggest that during exposure, PARP-1 impacts the stage of BER after excision of the deoxyribosephosphate moiety from the 5' end of DNA strand breaks by polymerase {beta}.

  8. Complete depletion of primordial germ cells in an All-female fish leads to Sex-biased gene expression alteration and sterile All-male occurrence.

    Science.gov (United States)

    Liu, Wei; Li, Shi-Zhu; Li, Zhi; Wang, Yang; Li, Xi-Yin; Zhong, Jian-Xiang; Zhang, Xiao-Juan; Zhang, Jun; Zhou, Li; Gui, Jian-Fang

    2015-11-18

    Gynogenesis is one of unisexual reproduction modes in vertebrates, and produces all-female individuals with identical genetic background. In sexual reproduction vertebrates, the roles of primordial germ cells on sexual dimorphism and gonadal differentiation have been largely studied, and two distinct functional models have been proposed. However, the role of primordial germ cells remains unknown in unisexual animals, and it is also unclear whether the functional models in sexual reproduction animals are common in unisexual animals. To solve these puzzles, we attempt to utilize the gynogenetic superiority of polyploid Carassius gibelio to create a complete germ cell-depleted gonad model by a similar morpholino-mediated knockdown approach used in other examined sexual reproduction fishes. Through the germ cell-depleted gonad model, we have performed comprehensive and comparative transcriptome analysis, and revealed a complete alteration of sex-biased gene expression. Moreover, the expression alteration leads to up-regulation of testis-biased genes and down-regulation of ovary-biased genes, and results in the occurrence of sterile all-males with testis-like gonads and secondary sex characteristics in the germ cell-depleted gynogenetic Carassius gibelio. Our current results have demonstrated that unisexual gynogenetic embryos remain keeping male sex determination information in the genome, and the complete depletion of primordial germ cells in the all-female fish leads to sex-biased gene expression alteration and sterile all-male occurrence.

  9. Differential downstream functions of protein kinase Ceta and -theta in EL4 mouse thymoma cells.

    Science.gov (United States)

    Resnick, M S; Kang, B S; Luu, D; Wickham, J T; Sando, J J; Hahn, C S

    1998-10-16

    Sensitive EL4 mouse thymoma cells (s-EL4) respond to phorbol esters with growth inhibition, adherence to substrate, and production of cytokines including interleukin 2. Since these cells express several of the phorbol ester-sensitive protein kinase C (PKC) isozymes, the function of each isozyme remains unclear. Previous studies demonstrated that s-EL4 cells expressed substantially more PKCeta and PKCtheta than did EL4 cells resistant to phorbol esters (r-EL4). To examine potential roles for PKCeta and PKCtheta in EL4 cells, wild type and constitutively active versions of the isozymes were transiently expressed using a Sindbis virus system. Expression of constitutively active PKCeta, but not PKCtheta, in s- and r-EL4 cells altered cell morphology and cytoskeletal structure in a manner similar to that of phorbol ester treatment, suggesting a role for PKCeta in cytoskeletal organization. Prolonged treatment of s-EL4 cells with phorbol esters results in inhibition of cell cycling along with a decreased expression of most of the PKC isozymes, including PKCtheta. Introduction of virally expressed PKCtheta, but not PKCeta, overcame the inhibitory effects of the prolonged phorbol ester treatment on cell cycle progression, suggesting a possible involvement of PKCtheta in cell cycle regulation. These results support differential functions for PKCeta and PKCtheta in T cell activation.

  10. The interaction between LYVE-1 with hyaluronan on the cell surface may play a role in the diversity of adhesion to cancer cells.

    Science.gov (United States)

    Du, Yan; Liu, Hua; He, Yiqing; Liu, Yiwen; Yang, Cuixia; Zhou, Muqing; Wang, Wenjuan; Cui, Lian; Hu, Jiajie; Gao, Feng

    2013-01-01

    Hyaluronan (HA), a simple disaccharide unit, can polymerize and is considered a primary component of the extracellular matrix, which has a wide range of biological functions. In recent years, HA was found on the surface of tumor cells. According to previous reports, differing HA content on the cell surface of tumor cells is closely related to lymph node metastases, but the mechanisms mediating this process remained unclear. This research intended to study the surface content of HA on tumor cells and analyze cell adhesive changes caused by the interaction between HA and its lymphatic endothelial receptor (LYVE-1). We screened and observed high HA content on HS-578T breast cells and low HA content on MCF-7 breast cells through particle exclusion, immunofluorescence and flow cytometry experiments. The expression of LYVE-1, the lymph-vessel specific HA receptor, was consistent with our previous report and enhanced the adhesion of HA(high)-HS-578T cells to COS-7(LYVE-1(+)) through HA in cell static adhesion and dynamic parallel plate flow chamber experiments. MCF-7 breast cells contain little HA on the surface; however, our results showed little adhesion difference between MCF-7 cells and COS-7(LYVE-1(+)) and COS-7(LYVE-1(-)) cells. Similar results were observed concerning the adhesion of HS-578T cells or MCF-7 cells to SVEC4-10 cells. Furthermore, we observed for the first time that the cell surface HA content of high transfer tumor cells was rich, and we visualized the cross-linking of HA cable structures, which may activate LYVE-1 on lymphatic endothelial cells, promoting tumor adhesion. In summary, high-low cell surface HA content of tumor cells through the interaction with LYVE-1 leads to adhesion differences.

  11. Probiotic Bifidobacterium breve induces IL-10-producing Tr1 cells in the colon.

    Directory of Open Access Journals (Sweden)

    Seong Gyu Jeon

    Full Text Available Specific intestinal microbiota has been shown to induce Foxp3(+ regulatory T cell development. However, it remains unclear how development of another regulatory T cell subset, Tr1 cells, is regulated in the intestine. Here, we analyzed the role of two probiotic strains of intestinal bacteria, Lactobacillus casei and Bifidobacterium breve in T cell development in the intestine. B. breve, but not L. casei, induced development of IL-10-producing Tr1 cells that express cMaf, IL-21, and Ahr in the large intestine. Intestinal CD103(+ dendritic cells (DCs mediated B. breve-induced development of IL-10-producing T cells. CD103(+ DCs from Il10(-/-, Tlr2(-/-, and Myd88(-/- mice showed defective B. breve-induced Tr1 cell development. B. breve-treated CD103(+ DCs failed to induce IL-10 production from co-cultured Il27ra(-/- T cells. B. breve treatment of Tlr2(-/- mice did not increase IL-10-producing T cells in the colonic lamina propria. Thus, B. breve activates intestinal CD103(+ DCs to produce IL-10 and IL-27 via the TLR2/MyD88 pathway thereby inducing IL-10-producing Tr1 cells in the large intestine. Oral B. breve administration ameliorated colitis in immunocompromised mice given naïve CD4(+ T cells from wild-type mice, but not Il10(-/- mice. These findings demonstrate that B. breve prevents intestinal inflammation through the induction of intestinal IL-10-producing Tr1 cells.

  12. Probiotic Bifidobacterium breve induces IL-10-producing Tr1 cells in the colon.

    Science.gov (United States)

    Jeon, Seong Gyu; Kayama, Hisako; Ueda, Yoshiyasu; Takahashi, Takuya; Asahara, Takashi; Tsuji, Hirokazu; Tsuji, Noriko M; Kiyono, Hiroshi; Ma, Ji Su; Kusu, Takashi; Okumura, Ryu; Hara, Hiromitsu; Yoshida, Hiroki; Yamamoto, Masahiro; Nomoto, Koji; Takeda, Kiyoshi

    2012-01-01

    Specific intestinal microbiota has been shown to induce Foxp3(+) regulatory T cell development. However, it remains unclear how development of another regulatory T cell subset, Tr1 cells, is regulated in the intestine. Here, we analyzed the role of two probiotic strains of intestinal bacteria, Lactobacillus casei and Bifidobacterium breve in T cell development in the intestine. B. breve, but not L. casei, induced development of IL-10-producing Tr1 cells that express cMaf, IL-21, and Ahr in the large intestine. Intestinal CD103(+) dendritic cells (DCs) mediated B. breve-induced development of IL-10-producing T cells. CD103(+) DCs from Il10(-/-), Tlr2(-/-), and Myd88(-/-) mice showed defective B. breve-induced Tr1 cell development. B. breve-treated CD103(+) DCs failed to induce IL-10 production from co-cultured Il27ra(-/-) T cells. B. breve treatment of Tlr2(-/-) mice did not increase IL-10-producing T cells in the colonic lamina propria. Thus, B. breve activates intestinal CD103(+) DCs to produce IL-10 and IL-27 via the TLR2/MyD88 pathway thereby inducing IL-10-producing Tr1 cells in the large intestine. Oral B. breve administration ameliorated colitis in immunocompromised mice given naïve CD4(+) T cells from wild-type mice, but not Il10(-/-) mice. These findings demonstrate that B. breve prevents intestinal inflammation through the induction of intestinal IL-10-producing Tr1 cells.

  13. MAIT cells are reduced in frequency and functionally impaired in human T lymphotropic virus type 1 infection: Potential clinical implications.

    Directory of Open Access Journals (Sweden)

    Dominic Paquin-Proulx

    Full Text Available HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. It is unclear why a minority of infected subjects develop HAM/TSP. The cellular immune response has been implicated in the development of inflammatory alterations in these patients; however the pathogenic mechanisms for disease progression remain unclear. Furthermore, HTLV-1-infected individuals have an increase incidence of Mycobacterium tuberculosis (Mtb infection, suggesting that immunological defect are associated with HTLV-1 infection. Evidence suggests an important role for Mucosal-associated invariant T (MAIT cells in the early control of Mtb infection. Chronic viral infections like HIV and HCV have been associated with decreased frequency and functionality of MAIT cells. We hypothesized that HTLV-1 infection is associated with similar perturbations in MAIT cells. We investigated MAIT cell frequency, phenotype, and function by flow cytometry in a cohort of 10 asymptomatic and 10 HAM/TSP HTLV-1 infected patients. We found that MAIT cells from HTLV-1-infected subjects were reduced and showed high co-expression of the activation markers CD38 and HLA-DR but normal levels of CCR6 and CD127. MAIT cells had a lower expression of the transcription factor PLZF in HAM/TSP patients. Unlike Tax-specific CD8+T cells, which are hyperfunctional, MAIT cells from HTLV-1-infected subjects had a poor IFNγ response following antigen stimulation. MAIT cell perturbations in HTLV-1 infection were not associated with HTLV-1 proviral load and MAIT cells were not infected by HTLV-1 in vivo. Rather, MAIT cells loss was associated with immune activation. Overall, our results do not support a role for MAIT cells in HAM/TSP pathogenesis but reduced numbers of MAIT cells, together with their poor functionality, could contribute to the increased susceptibility of HTLV-1-infected individuals to

  14. Self-assembled monolayers with different chemical group substrates for the study of MCF-7 breast cancer cell line behavior

    International Nuclear Information System (INIS)

    Yan, Hongji; Yin, Yanbin; Li, Yu; Tian, Weiming; Zhang, Song; Nie, Yongzhan; He, Jin; Wang, Xiumei; Cui, Fuzhai; Chen, Xiongbiao

    2013-01-01

    The interactions between cancer cells and the extracellular matrix (ECM) are important with respect to a number of cell behavoirs, yet remain unclear. In this study, self-assembled monolayers with different terminal chemical groups (hydroxyl (-OH), carboxyl (-COOH), animo (-NH 2 ), mercapto (-SH), and methyl (-CH 3 )) were employed as substrates for the culture of MCF-7 cells to examine effects on cell behavior. Cell spreading was investigated by scanning electron microscopy, tallin expression by immunofluorescence, proliferation rate by counting cell numbers, cell cycle by flow cytometry, metabolism by high-performance liquid chromatography and cell migration by live cell imaging. Annexin V-FITC (fluorescein isothiocyanate) and JC-1 assays were performed to determine cell apoptosis and mitochondrial membrane potential, respectively. Our results demonstrate the varied behaviors of MCF-7 cells in response to different chemical groups. Specifically, NH 2 and COOH terminal functional groups promote proliferation, the production of lactic acid and mobility of MCF-7 cells; SH and OH terminal groups enhance the expression and distribution of tallin but result in weak cell proliferation, metabolism, spreading and mobility. These results are meaningful for uncovering the interactions between the ECM and cancer cells; they are potentially useful for designing novel cancer treatment strategies. (paper)

  15. Stem cell niche-specific Ebf3 maintains the bone marrow cavity.

    Science.gov (United States)

    Seike, Masanari; Omatsu, Yoshiki; Watanabe, Hitomi; Kondoh, Gen; Nagasawa, Takashi

    2018-03-01

    Bone marrow is the tissue filling the space between bone surfaces. Hematopoietic stem cells (HSCs) are maintained by special microenvironments known as niches within bone marrow cavities. Mesenchymal cells, termed CXC chemokine ligand 12 (CXCL12)-abundant reticular (CAR) cells or leptin receptor-positive (LepR + ) cells, are a major cellular component of HSC niches that gives rise to osteoblasts in bone marrow. However, it remains unclear how osteogenesis is prevented in most CAR/LepR + cells to maintain HSC niches and marrow cavities. Here, using lineage tracing, we found that the transcription factor early B-cell factor 3 (Ebf3) is preferentially expressed in CAR/LepR + cells and that Ebf3-expressing cells are self-renewing mesenchymal stem cells in adult marrow. When Ebf3 is deleted in CAR/LepR + cells, HSC niche function is severely impaired, and bone marrow is osteosclerotic with increased bone in aged mice. In mice lacking Ebf1 and Ebf3 , CAR/LepR + cells exhibiting a normal morphology are abundantly present, but their niche function is markedly impaired with depleted HSCs in infant marrow. Subsequently, the mutants become progressively more osteosclerotic, leading to the complete occlusion of marrow cavities in early adulthood. CAR/LepR + cells differentiate into bone-producing cells with reduced HSC niche factor expression in the absence of Ebf1/Ebf3 Thus, HSC cellular niches express Ebf3 that is required to create HSC niches, to inhibit their osteoblast differentiation, and to maintain spaces for HSCs. © 2018 Seike et al.; Published by Cold Spring Harbor Laboratory Press.

  16. Lysophosphatidic Acid Upregulates Laminin-332 Expression during A431 Cell Colony Dispersal

    Directory of Open Access Journals (Sweden)

    Hironobu Yamashita

    2010-01-01

    Full Text Available Lysophosphatidic acid (LPA is a bioactive phospholipid that affects various biological functions, such as cell proliferation, migration, survival, wound healing, and tumor invasion through LPA receptors. Previously, we reported that LPA induces A431 colony dispersal, accompanied by disruption of cell-cell contacts and cell migration. However, it remains unclear how LPA affects cell migration and gene expression during A431 colony dispersal. In this paper, we performed cDNA microarray analysis to investigate this question by comparing gene expression between untreated and LPA-treated A431 cells. Interestingly, these results revealed that LPA treatment upregulates several TGF-β1 target genes, including laminin-332 (Ln-332 components (α3, β3, and γ2 chains. Western blot analysis also showed that LPA increased phosphorylation of Smad2, an event that is carried out by TGF-β1 interactions. Among the genes upregulated, we further addressed the role of Ln-332. Real-time PCR analysis confirmed the transcriptional upregulation of all α3, β3, and γ2 chains of Ln-332 by LPA, corresponding to the protein level increases revealed by western blot. Further, the addition of anti-Ln-332 antibody prevented LPA-treated A431 colonies from dispersing. Taken together, our results suggest that LPA-induced Ln-332 plays a significant role in migration of individual cells from A431 colonies.

  17. Adoptive transfer of EBV specific CD8+ T cell clones can transiently control EBV infection in humanized mice.

    Directory of Open Access Journals (Sweden)

    Olga Antsiferova

    2014-08-01

    Full Text Available Epstein Barr virus (EBV infection expands CD8+ T cells specific for lytic antigens to high frequencies during symptomatic primary infection, and maintains these at significant numbers during persistence. Despite this, the protective function of these lytic EBV antigen-specific cytotoxic CD8+ T cells remains unclear. Here we demonstrate that lytic EBV replication does not significantly contribute to virus-induced B cell proliferation in vitro and in vivo in a mouse model with reconstituted human immune system components (huNSG mice. However, we report a trend to reduction of EBV-induced lymphoproliferation outside of lymphoid organs upon diminished lytic replication. Moreover, we could demonstrate that CD8+ T cells against the lytic EBV antigen BMLF1 can eliminate lytically replicating EBV-transformed B cells from lymphoblastoid cell lines (LCLs and in vivo, thereby transiently controlling high viremia after adoptive transfer into EBV infected huNSG mice. These findings suggest a protective function for lytic EBV antigen-specific CD8+ T cells against EBV infection and against virus-associated tumors in extra-lymphoid organs. These specificities should be explored for EBV-specific vaccine development.

  18. Andrographolide inhibits growth of human T-cell acute lymphoblastic leukemia Jurkat cells by downregulation of PI3K/AKT and upregulation of p38 MAPK pathways

    Science.gov (United States)

    Yang, Tingfang; Yao, Shuluan; Zhang, Xianfeng; Guo, Yan

    2016-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) as a prevalent hematologic malignancy is one of the most common malignant tumors worldwide in children. Andrographolide (Andro), the major active component from Andrographis paniculata, has been shown to possess antitumor activities in several types of cancer cells. However, whether Andro would inhibit T-ALL cell growth remains unclear. In this study, we investigated the cytotoxic effect of Andro on human T-ALL Jurkat cells and explored the mechanisms of cell death. Cell apoptosis was assayed by flow cytometry, and the signaling transduction for Andro was analyzed by Western blotting. The results indicated 10 μg/mL Andro could significantly induce Jurkat cells’ apoptosis, depending on the inhibition of PI3K/AKT pathway. Moreover, Andro-induced apoptosis is enhanced by AKT-selective inhibitor LY294002. ERK- or JNK-selective inhibitors PD98059 and SP600125 had no effect on Andro-induced apoptosis. In addition, p38 inhibitor SB203580 could reverse Andro-induced apoptosis in Jurkat cells. We also found that the protein expression of p-p53 and p-p38 were increased after Andro treatments. The result of an in vivo study also demonstrated Andro’s dose-dependent inhibition in subcutaneous Jurkat xenografts. In conclusion, our findings explained a novel mechanism of drug action by Andro in Jurkat cells and suggested that Andro might be developed into a new candidate therapy for T-ALL patients in the coming days. PMID:27114702

  19. Abundant tax protein expression in CD4+ T cells infected with human T-cell lymphotropic virus type I (HTLV-I) is prevented by cytotoxic T lymphocytes.

    Science.gov (United States)

    Hanon, E; Hall, S; Taylor, G P; Saito, M; Davis, R; Tanaka, Y; Usuku, K; Osame, M; Weber, J N; Bangham, C R

    2000-02-15

    The role of the cellular immune response in human T-cell leukemia virus type I (HTLV-I) infection is not fully understood. A persistently activated cytotoxic T lymphocyte (CTL) response to HTLV-I is found in the majority of infected individuals. However, it remains unclear whether this CTL response is protective or causes tissue damage. In addition, several observations paradoxically suggest that HTLV-I is transcriptionally silent in most infected cells and, therefore, not detectable by virus-specific CTLs. With the use of a new flow cytometric procedure, we show here that a high proportion of naturally infected CD4+ peripheral blood mononuclear cells (PBMC) (between 10% and 80%) are capable of expressing Tax, the immunodominant target antigen recognized by virus-specific CTLs. Furthermore, we provide direct evidence that autologous CD8+ T cells rapidly kill CD4+ cells naturally infected with HTLV-I and expressing Tax in vitro by a perforin-dependent mechanism. Consistent with these observations, we observed a significant negative correlation between the frequency of Tax(11-19)-specific CD8+ T cells and the percentage of CD4+ T cells in peripheral blood of patients infected with HTLV-I. Those results are in accordance with the view that virus-specific CTLs participate in a highly efficient immune surveillance mechanism that persistently destroys Tax-expressing HTLV-I-infected CD4+ T cells in vivo. (Blood. 2000;95:1386-1392)

  20. Ribosome profiling-guided depletion of an mRNA increases cell growth rate and protein secretion

    DEFF Research Database (Denmark)

    Beuchert Kallehauge, Thomas; Li, Shangzhong; Pedersen, Lasse Ebdrup

    2017-01-01

    Recombinant protein production coopts the host cell machinery to provide high protein yields of industrial enzymes or biotherapeutics. However, since protein translation is energetically expensive and tightly controlled, it is unclear if highly expressed recombinant genes are translated as effici......Recombinant protein production coopts the host cell machinery to provide high protein yields of industrial enzymes or biotherapeutics. However, since protein translation is energetically expensive and tightly controlled, it is unclear if highly expressed recombinant genes are translated...... as efficiently as host genes. Furthermore, it is unclear how the high expression impacts global translation. Here, we present the first genome-wide view of protein translation in an IgG-producing CHO cell line, measured with ribosome profiling. Through this we found that our recombinant mRNAs were translated...... as efficiently as the host cell transcriptome, and sequestered up to 15% of the total ribosome occupancy. During cell culture, changes in recombinant mRNA translation were consistent with changes in transcription, demonstrating that transcript levels influence specific productivity. Using this information, we...

  1. The immune-enhancing activity of Cervus nippon mantchuricus extract (NGE) in RAW264.7 macrophage cells and immunosuppressed mice.

    Science.gov (United States)

    Hong, Se Hyang; Ku, Jin Mo; In Kim, Hyo; Ahn, Chang-Won; Park, Soo-Hyun; Seo, Hye Sook; Shin, Yong Cheol; Ko, Seong-Gyu

    2017-09-01

    Chemotherapeutics are often used to inhibit the proliferation of cancer cells. However, they can also harm healthy cells and cause side effects such as immunosuppression. Especially traditional oriental medicines long used in Asia, may be beneficial candidates for the alleviation of immune diseases. Cervus nippon mantchuricus extract (NGE) is currently sold in the market as coffee and health drinks. However, NGE was not widely investigated and efficacy remain unclear and essentially nothing is known about their potential immune-regulatory properties. As a result, NGE induced the differentiation of RAW264.7 macrophage cells. NGE-stimulated RAW264.7 macrophage cells elevated cytokines levels and NO production. NGE-stimulated RAW264.7 macrophage cells activated MAPKs and NF-κB signaling pathways. NGE encouraged the immuno-enhancing effects in immunosuppressed short-term treated with NGE mice model. NGE or Red ginseng encouraged the immuno-enhancing effects in immunosuppressed long-term treated with NGE mice model. Our data clearly show that NGE contains immune-enhancing activity and can be used to treat immunodeficiency. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Aubergine Controls Germline Stem Cell Self-Renewal and Progeny Differentiation via Distinct Mechanisms.

    Science.gov (United States)

    Ma, Xing; Zhu, Xiujuan; Han, Yingying; Story, Benjamin; Do, Trieu; Song, Xiaoqing; Wang, Su; Zhang, Ying; Blanchette, Marco; Gogol, Madelaine; Hall, Kate; Peak, Allison; Anoja, Perera; Xie, Ting

    2017-04-24

    Piwi family protein Aubergine (Aub) maintains genome integrity in late germ cells of the Drosophila ovary through Piwi-associated RNA-mediated repression of transposon activities. Although it is highly expressed in germline stem cells (GSCs) and early progeny, it remains unclear whether it plays any roles in early GSC lineage development. Here we report that Aub promotes GSC self-renewal and GSC progeny differentiation. RNA-iCLIP results show that Aub binds the mRNAs encoding self-renewal and differentiation factors in cultured GSCs. Aub controls GSC self-renewal by preventing DNA-damage-induced Chk2 activation and by translationally controlling the expression of self-renewal factors. It promotes GSC progeny differentiation by translationally controlling the expression of differentiation factors, including Bam. Therefore, this study reveals a function of Aub in GSCs and their progeny, which promotes translation of self-renewal and differentiation factors by directly binding to its target mRNAs and interacting with translational initiation factors. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Platelet-biased stem cells reside at the apex of the haematopoietic stem-cell hierarchy.

    Science.gov (United States)

    Sanjuan-Pla, Alejandra; Macaulay, Iain C; Jensen, Christina T; Woll, Petter S; Luis, Tiago C; Mead, Adam; Moore, Susan; Carella, Cintia; Matsuoka, Sahoko; Bouriez Jones, Tiphaine; Chowdhury, Onima; Stenson, Laura; Lutteropp, Michael; Green, Joanna C A; Facchini, Raffaella; Boukarabila, Hanane; Grover, Amit; Gambardella, Adriana; Thongjuea, Supat; Carrelha, Joana; Tarrant, Paul; Atkinson, Deborah; Clark, Sally-Ann; Nerlov, Claus; Jacobsen, Sten Eirik W

    2013-10-10

    The blood system is maintained by a small pool of haematopoietic stem cells (HSCs), which are required and sufficient for replenishing all human blood cell lineages at millions of cells per second throughout life. Megakaryocytes in the bone marrow are responsible for the continuous production of platelets in the blood, crucial for preventing bleeding--a common and life-threatening side effect of many cancer therapies--and major efforts are focused at identifying the most suitable cellular and molecular targets to enhance platelet production after bone marrow transplantation or chemotherapy. Although it has become clear that distinct HSC subsets exist that are stably biased towards the generation of lymphoid or myeloid blood cells, we are yet to learn whether other types of lineage-biased HSC exist or understand their inter-relationships and how differently lineage-biased HSCs are generated and maintained. The functional relevance of notable phenotypic and molecular similarities between megakaryocytes and bone marrow cells with an HSC cell-surface phenotype remains unclear. Here we identify and prospectively isolate a molecularly and functionally distinct mouse HSC subset primed for platelet-specific gene expression, with enhanced propensity for short- and long-term reconstitution of platelets. Maintenance of platelet-biased HSCs crucially depends on thrombopoietin, the primary extrinsic regulator of platelet development. Platelet-primed HSCs also frequently have a long-term myeloid lineage bias, can self-renew and give rise to lymphoid-biased HSCs. These findings show that HSC subtypes can be organized into a cellular hierarchy, with platelet-primed HSCs at the apex. They also demonstrate that molecular and functional priming for platelet development initiates already in a distinct HSC population. The identification of a platelet-primed HSC population should enable the rational design of therapies enhancing platelet output.

  4. Stem Cells in the Intestine: Possible Roles in Pathogenesis of Irritable Bowel Syndrome.

    Science.gov (United States)

    Ratanasirintrawoot, Sutheera; Israsena, Nipan

    2016-07-30

    Irritable bowel syndrome is one of the most common functional gastrointestinal (GI) disorders that significantly impair quality of life in patients. Current available treatments are still not effective and the pathophysiology of this condition remains unclearly defined. Recently, research on intestinal stem cells has greatly advanced our understanding of various GI disorders. Alterations in conserved stem cell regulatory pathways such as Notch, Wnt, and bone morphogenic protein/TGF- β have been well documented in diseases such as inflammatory bowel diseases and cancer. Interaction between intestinal stem cells and various signals from their environment is important for the control of stem cell self-renewal, regulation of number and function of specific intestinal cell types, and maintenance of the mucosal barrier. Besides their roles in stem cell regulation, these signals are also known to have potent effects on immune cells, enteric nervous system and secretory cells in the gut, and may be responsible for various aspects of pathogenesis of functional GI disorders, including visceral hypersensitivity, altered gut motility and low grade gut inflammation. In this article, we briefly summarize the components of these signaling pathways, how they can be modified by extrinsic factors and novel treatments, and provide evidenced support of their roles in the inflammation processes. Furthermore, we propose how changes in these signals may contribute to the symptom development and pathogenesis of irritable bowel syndrome.

  5. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  6. Critical protein GAPDH and its regulatory mechanisms in cancer cells

    International Nuclear Information System (INIS)

    Zhang, Jin-Ying; Zhang, Fan; Hong, Chao-Qun; Giuliano, Armando E.; Cui, Xiao-Jiang; Zhou, Guang-Ji; Zhang, Guo-Jun; Cui, Yu-Kun

    2015-01-01

    Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), initially identified as a glycolytic enzyme and considered as a housekeeping gene, is widely used as an internal control in experiments on proteins, mRNA, and DNA. However, emerging evidence indicates that GAPDH is implicated in diverse functions independent of its role in energy metabolism; the expression status of GAPDH is also deregulated in various cancer cells. One of the most common effects of GAPDH is its inconsistent role in the determination of cancer cell fate. Furthermore, studies have described GAPDH as a regulator of cell death; other studies have suggested that GAPDH participates in tumor progression and serves as a new therapeutic target. However, related regulatory mechanisms of its numerous cellular functions and deregulated expression levels remain unclear. GAPDH is tightly regulated at transcriptional and posttranscriptional levels, which are involved in the regulation of diverse GAPDH functions. Several cancer-related factors, such as insulin, hypoxia inducible factor-1 (HIF-1), p53, nitric oxide (NO), and acetylated histone, not only modulate GAPDH gene expression but also affect protein functions via common pathways. Moreover, posttranslational modifications (PTMs) occurring in GAPDH in cancer cells result in new activities unrelated to the original glycolytic function of GAPDH. In this review, recent findings related to GAPDH transcriptional regulation and PTMs are summarized. Mechanisms and pathways involved in GAPDH regulation and its different roles in cancer cells are also described

  7. Autophagy contributes to apoptosis in A20 and EL4 lymphoma cells treated with fluvastatin.

    Science.gov (United States)

    Qi, Xu-Feng; Kim, Dong-Heui; Lee, Kyu-Jae; Kim, Cheol-Su; Song, Soon-Bong; Cai, Dong-Qing; Kim, Soo-Ki

    2013-11-08

    Convincing evidence indicates that statins stimulate apoptotic cell death in several types of proliferating tumor cells in a cholesterol-lowering-independent manner. However, the relationship between apoptosis and autophagy in lymphoma cells exposed to statins remains unclear. The objective of this study was to elucidate the potential involvement of autophagy in fluvastatin-induced cell death of lymphoma cells. We found that fluvastatin treatment enhanced the activation of pro-apoptotic members such as caspase-3 and Bax, but suppressed the activation of anti-apoptotic molecule Bcl-2 in lymphoma cells including A20 and EL4 cells. The process was accompanied by increases in numbers of annexin V alone or annexin V/PI double positive cells. Furthermore, both autophagosomes and increases in levels of LC3-II were also observed in fluvastatin-treated lymphoma cells. However, apoptosis in fluvastatin-treated lymphoma cells could be blocked by the addition of 3-methyladenine (3-MA), the specific inhibitor of autophagy. Fluvastatin-induced activation of caspase-3, DNA fragmentation, and activation of LC3-II were blocked by metabolic products of the HMG-CoA reductase reaction, such as mevalonate, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP). These results suggest that autophagy contributes to fluvastatin-induced apoptosis in lymphoma cells, and that these regulating processes require inhibition of metabolic products of the HMG-CoA reductase reaction including mevalonate, FPP and GGPP.

  8. Increased apoptosis and peripheral blood mononuclear cell suppression of bone marrow mesenchymal stem cells in severe aplastic anemia.

    Science.gov (United States)

    Chao, Yu-Hua; Lin, Chiao-Wen; Pan, Hui-Hsien; Yang, Shun-Fa; Weng, Te-Fu; Peng, Ching-Tien; Wu, Kang-Hsi

    2018-06-05

    Although immune-mediated pathogenesis is considered an important aspect of severe aplastic anemia (SAA), its underlying mechanisms remain unclear. Mesenchymal stem cells (MSCs) are essential to the formation of specialized microenvironments in the bone marrow (BM), and MSC insufficiency can trigger the development of SAA. To find MSC alterations in the SAA BM, we compared BM MSCs from five children with SAA and five controls. Peripheral blood mononuclear cells (PBMCs) were cocultured with MSCs to evaluate the supportive effects of MSCs on hematopoiesis. Cytometric bead array immunoassay was used to determine cytokine excretion by MSCs. The immune functions of MSCs and their conditioned medium (CM) were evaluated by PBMC proliferation assays. SAA MSCs were characterized by a high percentage of cells in the abnormal sub-G1 phase of the cell cycle, which suggests an increased rate of apoptosis in SAA MSCs. In comparison with control MSCs, PBMCs cocultured with SAA MSCs displayed significantly reduced PBMC proliferation (P = 0.009). Aberrant cytokine profiles were secreted by SAA MSCs, with increased concentrations of interleukin-6, interferon-γ, tumor necrosis factor-α, and interleukin-1β in the CM. PBMC proliferation assays demonstrated additional immunosuppressive effects of SAA MSCs (P = 0.016) and their CM (P = 0.013). Our data revealed increased apoptosis and PBMC suppression of SAA MSCs. The alterations of MSCs may contribute to the formation of functionally abnormal microenvironments in SAA BM. © 2018 Wiley Periodicals, Inc.

  9. The role of TGF-β1–miR-21–ROS pathway in bystander responses induced by irradiated non-small-cell lung cancer cells

    Science.gov (United States)

    Jiang, Y; Chen, X; Tian, W; Yin, X; Wang, J; Yang, H

    2014-01-01

    Background: Many studies have indicated an important implication of radiation-induced bystander effects (RIBEs) in cancer radiotherapy, but the detailed signalling remains unclear. Methods: The roles of tumour growth factor-beta1 (TGF-β1) and miR-21 in medium-mediated RIBEs in H1299 non-small-cell lung cancer cells were investigated using DNA damage, changes in proliferation and levels of reactive oxygen species (ROS) as end points. SB431542, a specific inhibitor of TGF-β type 1 receptor kinases, was used to inhibit TGF-β1 pathways in irradiated and bystander cells. Exogenous miR-21 regulation was achieved through inhibitor or mimic transfection. Results: Compared with relative sham-radiation-conditioned medium, radiation-conditioned medium (RCM) from irradiated cells 1 h post radiation (1-h RCM) caused an increase in ROS levels and DNA damage in bystander cells, while 18-h RCM induced cell cycle delay and proliferation inhibition. All these effects were eliminated by TGF-βR1 inhibition. One-hour RCM upregulated miR-21 expression in bystander cells, and miR-21 inhibitor abolished bystander oxidative stress and DNA damage. Eighteen-hour RCM downregulated miR-21 of bystander cells, and miR-21 mimic eliminated bystander proliferation inhibition. Furthermore, the dysregulation of miR-21 was attenuated by TGF-βR1 inhibition. Conclusions: The TGF-β1–miR-21–ROS pathway of bystander cells has an important mediating role in RIBEs in H1299 cells. PMID:24992582

  10. JNK Promotes Epithelial Cell Anoikis by Transcriptional and Post-translational Regulation of BH3-Only Proteins

    Directory of Open Access Journals (Sweden)

    Nomeda Girnius

    2017-11-01

    Full Text Available Summary: Developmental morphogenesis, tissue injury, and oncogenic transformation can cause the detachment of epithelial cells. These cells are eliminated by a specialized form of apoptosis (anoikis. While the processes that contribute to this form of cell death have been studied, the underlying mechanisms remain unclear. Here, we tested the role of the cJUN NH2-terminal kinase (JNK signaling pathway using murine models with compound JNK deficiency in mammary and kidney epithelial cells. These studies demonstrated that JNK is required for efficient anoikis in vitro and in vivo. Moreover, JNK-promoted anoikis required pro-apoptotic members of the BCL2 family of proteins. We show that JNK acts through a BAK/BAX-dependent apoptotic pathway by increasing BIM expression and phosphorylating BMF, leading to death of detached epithelial cells. : Developmental morphogenesis, tissue injury, and oncogenic transformation can cause epithelial cell detachment. These cells are eliminated by a specialized form of apoptosis termed anoikis. Girnius and Davis show that anoikis is mediated by the cJUN NH2-terminal kinase (JNK, which increases BIM expression and phosphorylates BMF to engage BAK/BAX-dependent apoptosis. Keywords: apoptosis, anoikis, epithelial cell, mammary gland, JNK, BAX, BAK, BH3-only protein, BIM, BMF

  11. Proteomic Profiling of Ex Vivo Expanded CD34-Positive Haematopoetic Cells Derived from Umbilical Cord Blood

    Directory of Open Access Journals (Sweden)

    Heiner Falkenberg

    2013-01-01

    Full Text Available Ex vivo expansion of haematopoetic cells by application of specific cytokines is one approach to overcome boundaries in cord blood transplantation due to limited numbers of haematopoetic stem cells. While many protocols describe an effective increase of total cell numbers and the amount of CD34-positive cells, it still remains unclear if and how the procedure actually affects the cells’ properties. In the presented publications, CD34-positive cells were isolated from cord blood and expanded for up to 7 days in media supplemented with stem cell factor (SCF, thrombopoietin (THPO, interleukin 6 (IL-6, and fms-related tyrosine kinase 3 ligand (FLT3lg. At days 3 and 7, expanded cells were harvested and analyzed by flow cytometry and quantitative proteomics. 2970 proteins were identified, whereof proteomic analysis showed 440 proteins significantly changed in abundance during ex vivo expansion. Despite the fact that haematopoetic cells still expressed CD34 on the surface after 3 days, major changes in regard to the protein profile were observed, while further expansion showed less effect on the proteome level. Enrichment analysis of biological processes clearly showed a proteomic change toward a protein biosynthesis phenotype already within the first three days of expression.

  12. Temporal remodeling of the cell cycle accompanies differentiation in the Drosophila germline.

    Science.gov (United States)

    Hinnant, Taylor D; Alvarez, Arturo A; Ables, Elizabeth T

    2017-09-01

    Development of multicellular organisms relies upon the coordinated regulation of cellular differentiation and proliferation. Growing evidence suggests that some molecular regulatory pathways associated with the cell cycle machinery also dictate cell fate; however, it remains largely unclear how the cell cycle is remodeled in concert with cell differentiation. During Drosophila oogenesis, mature oocytes are created through a series of precisely controlled division and differentiation steps, originating from a single tissue-specific stem cell. Further, germline stem cells (GSCs) and their differentiating progeny remain in a predominantly linear arrangement as oogenesis proceeds. The ability to visualize the stepwise events of differentiation within the context of a single tissue make the Drosophila ovary an exceptional model for study of cell cycle remodeling. To describe how the cell cycle is remodeled in germ cells as they differentiate in situ, we used the Drosophila Fluorescence Ubiquitin-based Cell Cycle Indicator (Fly-FUCCI) system, in which degradable versions of GFP::E2f1 and RFP::CycB fluorescently label cells in each phase of the cell cycle. We found that the lengths of the G1, S, and G2 phases of the cell cycle change dramatically over the course of differentiation, and identified the 4/8-cell cyst as a key developmental transition state in which cells prepare for specialized cell cycles. Our data suggest that the transcriptional activator E2f1, which controls the transition from G1 to S phase, is a key regulator of mitotic divisions in the early germline. Our data support the model that E2f1 is necessary for proper GSC proliferation, self-renewal, and daughter cell development. In contrast, while E2f1 degradation by the Cullin 4 (Cul4)-containing ubiquitin E3 ligase (CRL4) is essential for developmental transitions in the early germline, our data do not support a role for E2f1 degradation as a mechanism to limit GSC proliferation or self-renewal. Taken

  13. The cellular uptake mechanism, intracellular transportation, and exocytosis of polyamidoamine dendrimers in multidrug-resistant breast cancer cells.

    Science.gov (United States)

    Zhang, Jie; Liu, Dan; Zhang, Mengjun; Sun, Yuqi; Zhang, Xiaojun; Guan, Guannan; Zhao, Xiuli; Qiao, Mingxi; Chen, Dawei; Hu, Haiyang

    2016-01-01

    Polyamidoamine dendrimers, which can deliver drugs and genetic materials to resistant cells, are attracting increased research attention, but their transportation behavior in resistant cells remains unclear. In this paper, we performed a systematic analysis of the cellular uptake, intracellular transportation, and efflux of PAMAM-NH2 dendrimers in multidrug-resistant breast cancer cells (MCF-7/ADR cells) using sensitive breast cancer cells (MCF-7 cells) as the control. We found that the uptake rate of PAMAM-NH2 was much lower and exocytosis of PAMAM-NH2 was much greater in MCF-7/ADR cells than in MCF-7 cells due to the elimination of PAMAM-NH2 from P-glycoprotein and the multidrug resistance-associated protein in MCF-7/ADR cells. Macropinocytosis played a more important role in its uptake in MCF-7/ADR cells than in MCF-7 cells. PAMAM-NH2 aggregated and became more degraded in the lysosomal vesicles of the MCF-7/ADR cells than in those of the MCF-7 cells. The endoplasmic reticulum and Golgi complex were found to participate in the exocytosis rather than endocytosis process of PAMAM-NH2 in both types of cells. Our findings clearly showed the intracellular transportation process of PAMAM-NH2 in MCF-7/ADR cells and provided a guide of using PAMAM-NH2 as a drug and gene vector in resistant cells.

  14. Diet-Induced Obesity Is Associated with an Impaired NK Cell Function and an Increased Colon Cancer Incidence

    Directory of Open Access Journals (Sweden)

    Ina Bähr

    2017-01-01

    Full Text Available Obesity is associated with an increased colon cancer incidence, but underlying mechanisms remained unclear. Previous studies showed altered Natural killer (NK cell functions in obese individuals. Therefore, we studied the impact of an impaired NK cell functionality on the increased colon cancer risk in obesity. In vitro investigations demonstrated a decreased IFN-γ secretion and cytotoxicity of human NK cells against colon tumor cells after NK cell preincubation with the adipokine leptin. In addition, leptin incubation decreased the expression of activating NK cell receptors. In animal studies, colon cancer growth was induced by injection of azoxymethane (AOM in normal weight and diet-induced obese rats. Body weight and visceral fat mass were increased in obese animals compared to normal weight rats. AOM-treated obese rats showed an increased quantity, size, and weight of colon tumors compared to the normal weight tumor group. Immunohistochemical analyses demonstrated a decreased number of NK cells in spleen and liver in obesity. Additionally, the expression levels of activating NK cell receptors were lower in spleen and liver of obese rats. The results show for the first time that the decreased number and impaired NK cell function may be one cause for the higher colon cancer risk in obesity.

  15. A framework for quantification and physical modeling of cell mixing applied to oscillator synchronization in vertebrate somitogenesis

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    Koichiro Uriu

    2017-08-01

    Full Text Available In development and disease, cells move as they exchange signals. One example is found in vertebrate development, during which the timing of segment formation is set by a ‘segmentation clock’, in which oscillating gene expression is synchronized across a population of cells by Delta-Notch signaling. Delta-Notch signaling requires local cell-cell contact, but in the zebrafish embryonic tailbud, oscillating cells move rapidly, exchanging neighbors. Previous theoretical studies proposed that this relative movement or cell mixing might alter signaling and thereby enhance synchronization. However, it remains unclear whether the mixing timescale in the tissue is in the right range for this effect, because a framework to reliably measure the mixing timescale and compare it with signaling timescale is lacking. Here, we develop such a framework using a quantitative description of cell mixing without the need for an external reference frame and constructing a physical model of cell movement based on the data. Numerical simulations show that mixing with experimentally observed statistics enhances synchronization of coupled phase oscillators, suggesting that mixing in the tailbud is fast enough to affect the coherence of rhythmic gene expression. Our approach will find general application in analyzing the relative movements of communicating cells during development and disease.

  16. Vascular and perivascular niches, but not the osteoblastic niche, are numerically restored following allogeneic hematopoietic stem cell transplantation in patients with aplastic anemia.

    Science.gov (United States)

    Wu, Liangliang; Mo, Wenjian; Zhang, Yuping; Zhou, Ming; Li, Yumiao; Zhou, Ruiqing; Xu, Shiling; Pan, Shiyi; Deng, Hui; Mao, Ping; Wang, Shunqing

    2017-07-01

    Bone marrow (BM) niches, including the osteoblastic, vascular, and perivascular niches, are numerically impaired in patients with aplastic anemia (AA). It remains unclear whether these niches are numerically restored in AA patients after allogenic hematopoietic stem cell transplantation (allo-HSCT). To investigate changes in BM niches, we monitored 52 patients with AA who had undergone allo-HSCT and performed immunohistochemical studies of BM niches using antibodies against CD34, CD146, and osteopontin. After allo-HSCT, patients with AA exhibited a remarkable increase in the number of cellular elements in the BM niches, including the vascular and perivascular cells. However, no significant differences in endosteal cells were detected. We explored the cause of this restoration by analyzing the origin of BM mesenchymal stem cells (BM-MSCs) and the expression of cytokines in BM plasma. STR-PCR revealed that the BM-MSCs were derived from the host, not the donor. In addition, significantly elevated levels of vascular endothelial growth factor (VEGF) were found after allo-HSCT. Our data indicates that vascular and perivascular niches are numerically restored, but the endosteal niche remains numerically impaired in patients with AA after allo-HSCT, and that levels of VEGF, but not donor-derived BM-MSCs, may correlate with the restoration of BM niches.

  17. Appearance of differentiated cells derived from polar body nuclei in the silkworm, Bombyx mori

    Directory of Open Access Journals (Sweden)

    Hiroki eSakai

    2013-09-01

    Full Text Available AbstractIn Bombyx mori, polar body nuclei are observed until 9h after egg lying, however, the fate of polar body nuclei remains unclear. To examine the fate of polar body nuclei, we employed a mutation of serosal cell pigmentation, pink-eyed white egg (pe. The heterozygous pe/+pe females produced black serosal cells in white eggs, while pe/pe females did not produce black serosal cells in white eggs. These results suggest that the appearance of black serosal cells in white eggs depends on the genotype (pe/ +pe of the mother. Because the polar body nuclei had +pe genes in the white eggs laid by a pe/ +pe female, polar body nuclei participate in development and differentiate into functional cell (serosal cells. Analyses of serosal cells pigmentation indicated that approximately 30% of the eggs contained polar-body-nucleus-derived cells. These results demonstrate that polar-body-nucleus-derived cells appeared at a high frequency under natural conditions. Approximately 80% of polar-body-nucleus-derived cells appeared near the anterior pole and the dorsal side, which is opposite to where embryogenesis occurs. The number of cells derived from the polar body nuclei was very low. Approximately 26 % of these eggs contained only one black serosal cell. PCR-based analysis revealed that the polar-body-nucleus-derived cells disappeared in late embryonic stages (stage 25. Overall, polar-body-nuclei-derived cells were unlikely to contribute to embryos.

  18. Balance of unidirectional monovalent ion fluxes in cells undergoing apoptosis: why does Na+/K+ pump suppression not cause cell swelling?

    Science.gov (United States)

    Yurinskaya, Valentina E; Rubashkin, Andrey A; Vereninov, Alexey A

    2011-05-01

    Cells dying according to the apoptotic program, unlike cells dying via an unprogrammed mode, are able to avoid swelling and osmotic bursting with membrane disruption.There are indications that apoptosis is accompanied by suppression of the Na+/K+ pump and changes in the K+ and Cl− channels. It remains unclear how ion fluxes through individual ion pathways are integrated so as to induce loss of intracellular ions and concomitant apoptotic volume decrease. A decrease in activity of the sodium pump during apoptosis should cause cell swelling rather than shrinkage. We have made the first systemic analysis of the monovalent ion flux balance in apoptotic cells. Experimental data were obtained for human U937 cells treated with staurosporine for 4–5 h, which is known to induce apoptosis. The data include cellular Cl− content and fluxes, K+, Na+, water content and ouabain-sensitive and -resistant Rb+ fluxes.Unidirectional monovalent ion fluxeswere calculated using these data and a cell model comprising the double Donnan system with the Na+/K+ pump, Cl−, K+, Na+ channels, the Na+–K+–2Cl−cotransporter (NKCC), the Na+–Cl− cotransporter (NC), and the equivalent Cl−/Cl− exchange.Apoptotic cell shrinkage was found to be caused, depending on conditions, either by an increase in the integral channel permeability of membrane for K+ or by suppression of the pump coupledwith a decrease in the integral channel permeability of membrane for Na+. The decrease in the channel permeability of membrane for Na+ plays a crucial role in cell dehydration in apoptosis accompanied by suppression of the pump. Supplemental Table S1 is given for easy calculating flux balance under specified conditions.

  19. The roles of supernatant of macrophage treated by excretory-secretory products from muscle larvae of Trichinella spiralis on the differentiation of C2C12 myoblasts

    Science.gov (United States)

    The excretory-secretory products (ESPs) released by the muscle-larvae (ML) stage of Trichinella spiralis have been suggested to be involved in nurse cell formation. However, the molecular mechanisms by which ML-ESPs modulate nurse cell formation remain unclear. Macrophages exert either beneficial or...

  20. Are mast cells instrumental for fibrotic diseases?

    Directory of Open Access Journals (Sweden)

    Catherine eOvered-Sayer

    2014-01-01

    Full Text Available Idiopathic pulmonary fibrosis (IPF is a fatal lung disorder of unknown etiology characterised by accumulation of lung fibroblasts and extracellular matrix deposition, ultimately leading to compromised tissue architecture and lung function capacity. IPF has a heterogeneous clinical course; however the median survival after diagnosis is only 3-5 years. The pharmaceutical and biotechnology industry has made many attempts to find effective treatments for IPF, but the disease has so far defied all attempts at therapeutic intervention. Clinical trial failures may arise for many reasons, including disease heterogeneity, lack of readily measurable clinical end points other than overall survival, and, perhaps most of all, a lack of understanding of the underlying molecular mechanisms of the progression of IPF.The precise link between inflammation and fibrosis remains unclear, but it appears that immune cells can promote fibrosis by releasing fibrogenic factors. So far, however, therapeutic approaches targeting macrophages, neutrophils, or lymphocytes have failed to alter disease pathogenesis. A new cell to garner research interest in fibrosis is the mast cell. Increased numbers of mast cells have long been known to be present in pulmonary fibrosis and clinically correlations between mast cells and fibrosis have been reported. More recent data suggests that mast cells may contribute to the fibrotic process by stimulating fibroblasts resident in the lung, thus driving the pathogenesis of the disease. In this review, we will discuss the mast cell and its physiological role in tissue repair and remodelling, as well as its pathological role in fibrotic diseases such as IPF, where the process of tissue repair and remodelling is thought to be dysregulated.

  1. Flaxseed oil supplementation manipulates correlations between serum individual mol % free fatty acid levels and insulin resistance in type 2 diabetics. Insulin resistance and percent remaining pancreatic β-cell function are unaffected.

    Science.gov (United States)

    Barre, D E; Mizier-Barre, K A; Griscti, O; Hafez, K

    2016-10-01

    Elevated total serum free fatty acids (FFAs) concentrations have been suggested, controversially, to enhance insulin resistance and decrease percent remaining β-cell function. However, concentrations of individual serum FFAs have never been published in terms of their relationship (correlation) to homeostatic model assessment-insulin resistance (HOMA-IR) and percent remaining β-cell function (HOMA-%β) in the type 2 diabetics (T2Ds). Alpha-linolenic acid consumption has a negative correlation with the insulin resistance, which in turn is negatively correlated with the remaining β-cell function. The primary objective was to test the hypothesis that there would be different relationship (correlation) between the blood serum individual free FFA mol % levels and HOMA-IR and/or HOMA-%β in T2D. The secondary objective was to test the hypothesis that flaxseed oil, previously being shown to be ineffective in the glycemic control in T2Ds, may alter these correlations in a statistically significant manner as well as HOMA-IR and/or HOMA-%β. Patients were recruited via a newspaper advertisement and two physicians have been employed. All the patients came to visit one and three months later for a second visit. At the second visit, the subjects were randomly assigned (double blind) to flaxseed or safflower oil treatment for three months, until the third visit. Different statistically significant correlations or trends towards among some serum individual free FFA mol % levels and HOMA-IR and HOMA-%β, pre- and post-flaxseed and safflower oil supplementation were found. However, flaxseed oil had no impact on HOMA-IR or HOMA-%β despite statistically significant alterations in correlations compared to baseline HOMA-IR. The obtained data indicate that high doses of flaxseed oil have no statistically significant effect on HOMA-IR or HOMA-%β in T2Ds, probably due to the additive effects of negative and positive correlations.

  2. Prefrontal cortical parvalbumin and somatostatin expression and cell density increase during adolescence and are modified by BDNF and sex.

    Science.gov (United States)

    Du, X; Serena, K; Hwang, W; Grech, A M; Wu, Y W C; Schroeder, A; Hill, R A

    2018-04-01

    Brain-derived neurotrophic factor (BDNF) is known to play a critical role early in the development of cortical GABAergic interneurons. Recently our laboratory and others have shown protracted development of specific subpopulations of GABAergic interneurons extending into adolescence. BDNF expression also changes significantly across adolescent development. However the role of BDNF in regulating GABAergic changes across adolescence remains unclear. Here, we performed