WorldWideScience

Sample records for myeloid cell function

  1. Metalloproteinases: a Functional Pathway for Myeloid Cells.

    Science.gov (United States)

    Chou, Jonathan; Chan, Matilda F; Werb, Zena

    2016-04-01

    Myeloid cells have diverse roles in regulating immunity, inflammation, and extracellular matrix turnover. To accomplish these tasks, myeloid cells carry an arsenal of metalloproteinases, which include the matrix metalloproteinases and the adamalysins. These enzymes have diverse substrate repertoires, and are thus involved in mediating proteolytic cascades, cell migration, and cell signaling. Dysregulation of metalloproteinases contributes to pathogenic processes, including inflammation, fibrosis, and cancer. Metalloproteinases also have important nonproteolytic functions in controlling cytoskeletal dynamics during macrophage fusion and enhancing transcription to promote antiviral immunity. This review highlights the diverse contributions of metalloproteinases to myeloid cell functions.

  2. Myeloid dendritic cells: Development, functions, and role in atherosclerotic inflammation.

    Science.gov (United States)

    Chistiakov, Dimitry A; Sobenin, Igor A; Orekhov, Alexander N; Bobryshev, Yuri V

    2015-06-01

    Myeloid dendritic cells (mDCs) comprise a heterogeneous population of professional antigen-presenting cells, which are responsible for capture, processing, and presentation of antigens on their surface to T cells. mDCs serve as a bridge linking adaptive and innate immune responses. To date, the development of DC lineage in bone marrow is better characterized in mice than in humans. DCs and macrophages share the common myeloid progenitor called macrophage-dendritic cell progenitor (MDP) that gives rise to monocytoid lineage and common DC progenitors (CDPs). CDP in turn gives rise to plasmacytoid DCs and predendritic cells (pre-mDCs) that are common precursor of myeloid CD11b+ and CD8α(+) DCs. The development and commitment of mDCs is regulated by several transcription and hematopoietic growth factors of which CCr7, Zbtb46, and Flt3 represent 'core' genes responsible for development and functional and phenotypic maintenance of mDCs. mDCs were shown to be involved in the pathogenesis of many autoimmune and inflammatory diseases including atherosclerosis. In atherogenesis, different subsets of mDCs could possess both proatherogenic (e.g. proinflammatory) and atheroprotective (e.g. anti-inflammatory and tolerogenic) activities. The proinflammatory role of mDCs is consisted in production of inflammatory molecules and priming proinflammatory subsets of effector T cells. In contrast, tolerogenic mDCs fight against inflammation through arrest of activity of proinflammatory T cells and macrophages and induction of immunosuppressive regulatory T cells. Microenvironmental conditions trigger differentiation of mDCs to acquire proinflammatory or regulatory properties.

  3. Functional inhibition of mesenchymal stromal cells in acute myeloid leukemia.

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    Geyh, S; Rodríguez-Paredes, M; Jäger, P; Khandanpour, C; Cadeddu, R-P; Gutekunst, J; Wilk, C M; Fenk, R; Zilkens, C; Hermsen, D; Germing, U; Kobbe, G; Lyko, F; Haas, R; Schroeder, T

    2016-03-01

    Hematopoietic insufficiency is the hallmark of acute myeloid leukemia (AML) and predisposes patients to life-threatening complications such as bleeding and infections. Addressing the contribution of mesenchymal stromal cells (MSC) to AML-induced hematopoietic failure we show that MSC from AML patients (n=64) exhibit significant growth deficiency and impaired osteogenic differentiation capacity. This was molecularly reflected by a specific methylation signature affecting pathways involved in cell differentiation, proliferation and skeletal development. In addition, we found distinct alterations of hematopoiesis-regulating factors such as Kit-ligand and Jagged1 accompanied by a significantly diminished ability to support CD34+ hematopoietic stem and progenitor cells in long-term culture-initiating cells (LTC-ICs) assays. This deficient osteogenic differentiation and insufficient stromal support was reversible and correlated with disease status as indicated by Osteocalcin serum levels and LTC-IC frequencies returning to normal values at remission. In line with this, cultivation of healthy MSC in conditioned medium from four AML cell lines resulted in decreased proliferation and osteogenic differentiation. Taken together, AML-derived MSC are molecularly and functionally altered and contribute to hematopoietic insufficiency. Inverse correlation with disease status and adoption of an AML-like phenotype after exposure to leukemic conditions suggests an instructive role of leukemic cells on bone marrow microenvironment.

  4. Coordinated regulation of myeloid cells by tumours.

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    Gabrilovich, Dmitry I; Ostrand-Rosenberg, Suzanne; Bronte, Vincenzo

    2012-03-22

    Myeloid cells are the most abundant nucleated haematopoietic cells in the human body and are a collection of distinct cell populations with many diverse functions. The three groups of terminally differentiated myeloid cells - macrophages, dendritic cells and granulocytes - are essential for the normal function of both the innate and adaptive immune systems. Mounting evidence indicates that the tumour microenvironment alters myeloid cells and can convert them into potent immunosuppressive cells. Here, we consider myeloid cells as an intricately connected, complex, single system and we focus on how tumours manipulate the myeloid system to evade the host immune response.

  5. Histone deacetylase 11: A novel epigenetic regulator of myeloid derived suppressor cell expansion and function.

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    Sahakian, Eva; Powers, John J; Chen, Jie; Deng, Susan L; Cheng, Fengdong; Distler, Allison; Woods, David M; Rock-Klotz, Jennifer; Sodre, Andressa L; Youn, Je-In; Woan, Karrune V; Villagra, Alejandro; Gabrilovich, Dmitry; Sotomayor, Eduardo M; Pinilla-Ibarz, Javier

    2015-02-01

    Myeloid-derived suppressor cells (MDSCs), a heterogeneous population of cells capable of suppressing anti-tumor T cell function in the tumor microenvironment, represent an imposing obstacle in the development of cancer immunotherapeutics. Thus, identifying elements essential to the development and perpetuation of these cells will undoubtedly improve our ability to circumvent their suppressive impact. HDAC11 has emerged as a key regulator of IL-10 gene expression in myeloid cells, suggesting that this may represent an important targetable axis through which to dampen MDSC formation. Using a murine transgenic reporter model system where eGFP expression is controlled by the HDAC11 promoter (Tg-HDAC11-eGFP), we provide evidence that HDAC11 appears to function as a negative regulator of MDSC expansion/function in vivo. MDSCs isolated from EL4 tumor-bearing Tg-HDAC11-eGFP display high expression of eGFP, indicative of HDAC11 transcriptional activation at steady state. In striking contrast, immature myeloid cells in tumor-bearing mice display a diminished eGFP expression, implying that the transition of IMC to MDSC's require a decrease in the expression of HDAC11, where we postulate that it acts as a gate-keeper of myeloid differentiation. Indeed, tumor-bearing HDAC11-knockout mice (HDAC11-KO) demonstrate a more suppressive MDSC population as compared to wild-type (WT) tumor-bearing control. Notably, the HDAC11-KO tumor-bearing mice exhibit enhanced tumor growth kinetics when compare to the WT control mice. Thus, through a better understanding of this previously unknown role of HDAC11 in MDSC expansion and function, rational development of targeted epigenetic modifiers may allow us to thwart a powerful barrier to efficacious immunotherapies.

  6. Energy metabolism drives myeloid-derived suppressor cell differentiation and functions in pathology.

    Science.gov (United States)

    Sica, Antonio; Strauss, Laura

    2017-08-01

    Over the last decade, a heterogeneous population of immature myeloid cells with major regulatory functions has been described in cancer and other pathologic conditions and ultimately defined as MDSCs. Most of the early work on the origins and functions of MDSCs has been in murine and human tumor bearers in which MDSCs are known to be immunosuppressive and to result in both reduced immune surveillance and antitumor cytotoxicity. More recent studies, however, suggest that expansion of these immature myeloid cells may be linked to most, if not all, chronic and acute inflammatory processes. The universal expansion to inflammatory stimuli of MDSCs suggests that these cells may be more of a normal component of the inflammatory response (emergency myelopoiesis) than simply a pathologic response to a growing tumor. Instead of an adverse immunosuppressive response, expansion of these immature myeloid cell populations may result from a complex balance between increased immune surveillance and dampened adaptive immune responses that are common to many inflammatory responses. Within this scenario, new pathways of metabolic reprogramming are emerging as drivers of MDSC differentiation and functions in cancer and inflammatory disorders, crucially linking metabolic syndrome to inflammatory processes. © Society for Leukocyte Biology.

  7. Phenotype and function of myeloid dendritic cells derived from African green monkey blood monocytes.

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    Mortara, Lorenzo; Ploquin, Mickaël J-Y; Faye, Abdourahmane; Scott-Algara, Daniel; Vaslin, Bruno; Butor, Cécile; Hosmalin, Anne; Barré-Sinoussi, Françoise; Diop, Ousmane M; Müller-Trutwin, Michaela C

    2006-01-20

    Myeloid dendritic cells probably play an important role in the immune response against HIV and SIV, and in the enhancement of CD4+ T cell infection. Here, we have investigated phenotypic and functional features of myeloid monocyte-derived DC (MDDC) from African green monkeys (AGMs). AGMs are natural hosts of SIV and exhibit no signs of abnormal T cell activation despite high SIV plasma viremia. We identified mAbs that cross-react specifically with homologous molecules expressed on AGM DC. We adapted a protocol to derive AGM MDDC by culture in the presence of GM-CSF and IL-4. The differentiated cells possessed a typical dendritic morphology and the majority were CD11c+ DC-SIGN+. AGM MDDC displayed a high expression of typical maturation markers, such as CD83, CD86 and DC-LAMP, and moderate immunostimulatory capacity, suggesting that the cells were in a semi-mature state. Stimulation resulted in further maturation, as shown by up-regulation of CD80 and decrease of endocytosis ability. However, neither increase of HLA-DR or CD40 expression nor enhanced immunostimulatory capacity was observed. The latter was associated with a low pro-inflammatory cytokine production during mixed lymphocyte reactions and a cytokine balance in favour of IL-10 in contrast to human MDDC. This is the first characterization of AGM MDDC. The tools described here are a crucial step for future studies in vivo or in vitro on the function of myeloid DC using the AGM animal model.

  8. Leukemia-induced phenotypic and functional defects in natural killer cells predict failure to achieve remission in acute myeloid leukemia.

    Science.gov (United States)

    Stringaris, Kate; Sekine, Takuya; Khoder, Ahmad; Alsuliman, Abdullah; Razzaghi, Bonnie; Sargeant, Ruhena; Pavlu, Jiri; Brisley, Gill; de Lavallade, Hugues; Sarvaria, Anushruthi; Marin, David; Mielke, Stephan; Apperley, Jane F; Shpall, Elizabeth J; Barrett, A John; Rezvani, Katayoun

    2014-05-01

    The majority of patients with acute myeloid leukemia will relapse, and older patients often fail to achieve remission with induction chemotherapy. We explored the possibility that leukemic suppression of innate immunity might contribute to treatment failure. Natural killer cell phenotype and function was measured in 32 consecutive acute myeloid leukemia patients at presentation, including 12 achieving complete remission. Compared to 15 healthy age-matched controls, natural killer cells from acute myeloid leukemia patients were abnormal at presentation, with downregulation of the activating receptor NKp46 (P=0.007) and upregulation of the inhibitory receptor NKG2A (P=0.04). Natural killer cells from acute myeloid leukemia patients had impaired effector function against autologous blasts and K562 targets, with significantly reduced CD107a degranulation, TNF-α and IFN-γ production. Failure to achieve remission was associated with NKG2A overexpression and reduced TNF-α production. These phenotypic and functional abnormalities were partially restored in the 12 patients achieving remission. In vitro co-incubation of acute myeloid leukemia blasts with natural killer cells from healthy donors induced significant impairment in natural killer cell TNF-α and IFN-γ production (P=0.02 and P=0.01, respectively) against K562 targets and a trend to reduced CD107a degranulation (P=0.07). Under transwell conditions, the inhibitory effect of AML blasts on NK cytotoxicity and effector function was still present, and this inhibitory effect was primarily mediated by IL-10. These results suggest that acute myeloid leukemia blasts induce long-lasting changes in natural killer cells, impairing their effector function and reducing the competence of the innate immune system, favoring leukemia survival.

  9. Genotypic and functional diversity of phenotypically defined primitive hematopoietic cells in patients with chronic myeloid leukemia.

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    Sloma, Ivan; Beer, Philip A; Saw, Kyi Min; Chan, Matthew; Leung, Donna; Raghuram, Kamini; Brimacombe, Cedric; Johnston, Bobby; Lambie, Karen; Forrest, Donna; Jiang, Xiaoyan; Eaves, Connie J

    2013-10-01

    Much progress has been made in the management of chronic-phase chronic myeloid leukemia (CP-CML), but there is a continuing imperative to develop curative treatments, predict patient responses to specific modalities, and anticipate disease relapse or progression. These needs underlie continuing interest in methods to detect and quantify the relevant leukemic cells in clinical samples with improved reliability and specificity. We report the results of comparing three methods to enumerate primitive CP-CML cells in the same samples: genotyping CD34(+)38(-) cells directly by fluorescence in situ hybridization, and measuring BCR-ABL1 transcript-genotyped colony-forming cell outputs in either 5-week long-term cultures (LTCs) containing non-engineered mouse fibroblasts or in 6-week LTCs containing mouse fibroblasts engineered to produce human Steel factor, granulocyte colony-stimulating factor, and IL-3. The results demonstrate that the first two methods significantly overestimate the prevalence of primitive CP-CML cells by comparison to the third. In additional studies, we found that CML-CD34(+) cells can repopulate the marrow and spleen of serially transplanted adult NOD/SCID-IL-2Rγ chain-null mice for more than 1 year with an almost exclusive myeloid differentiation in primary and secondary recipients and without evidence of disease progression. These findings underscore the importance of long-term functional in vitro and in vivo endpoints to identify and characterize CP-CML stem cells. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  10. Polysaccharide from Lentinus edodes inhibits the immunosuppressive function of myeloid-derived suppressor cells.

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    Hao Wu

    Full Text Available Reversing the function of immune suppressor cells may improve the efficacy of cancer therapy. Here, we have isolated a novel polysaccharide MPSSS (577.2 Kd from Lentinus edodes and examined its effects on differentiation and function of myeloid-derived suppressor cells (MDSCs. MPSSS is composed of glucose (75.0%, galactose (11.7%, mannose (7.8%, and xylose (0.4%. In vivo, it inhibits the growth of McgR32 tumor cells, which is correlated with a reduced percentage of MDSCs in peripheral blood. In vitro, it induces both morphological and biophysical changes in MDSCs. Importantly, MPSSS up-regulates MHC II and F4/80 expression on MDSCs, and reverses their inhibition effect on CD4(+ T cells in a dose-dependent manner. The mechanism study shows that MPSSS may stimulate MDSCs through a MyD88 dependent NF-κB signaling pathway. Together, we demonstrated for the first time that MPSSS stimulates the differentiation of MDSCs and reverses its immunosuppressive functions, shedding new light on developing novel anti-cancer strategies by targeting MDSCs.

  11. Surface Glycoproteins of Exosomes Shed by Myeloid-Derived Suppressor Cells Contribute to Function.

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    Chauhan, Sitara; Danielson, Steven; Clements, Virginia; Edwards, Nathan; Ostrand-Rosenberg, Suzanne; Fenselau, Catherine

    2017-01-06

    In this report, we use a proteomic strategy to identify glycoproteins on the surface of exosomes derived from myeloid-derived suppressor cells (MDSCs), and then test if selected glycoproteins contribute to exosome-mediated chemotaxis and migration of MDSCs. We report successful modification of a surface chemistry method for use with exosomes and identify 21 surface N-glycoproteins on exosomes released by mouse mammary carcinoma-induced MDSCs. These glycoprotein identities and functionalities are compared with 93 N-linked glycoproteins identified on the surface of the parental cells. As with the lysate proteomes examined previously, the exosome surface N-glycoproteins are primarily a subset of the glycoproteins on the surface of the suppressor cells that released them, with related functions and related potential as therapeutic targets. The "don't eat me" molecule CD47 and its binding partners thrombospondin-1 (TSP1) and signal regulatory protein α (SIRPα) were among the surface N-glycoproteins detected. Functional bioassays using antibodies to these three molecules demonstrated that CD47, TSP1, and to a lesser extent SIRPα facilitate exosome-mediated MDSC chemotaxis and migration.

  12. A Rapid Culture Technique Produces Functional Dendritic-Like Cells from Human Acute Myeloid Leukemia Cell Lines

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    Jian Ning

    2011-01-01

    Full Text Available Most anti-cancer immunotherapeutic strategies involving dendritic cells (DC as vaccines rely upon the adoptive transfer of DC loaded with exogenous tumour-peptides. This study utilized human acute myeloid leukemia (AML cells as progenitors from which functional dendritic-like antigen presenting cells (DLC were generated, that constitutively express tumour antigens for recognition by CD8+ T cells. DLC were generated from AML cell lines KG-1 and MUTZ-3 using rapid culture techniques and appropriate cytokines. DLC were evaluated for their cell-surface phenotype, antigen uptake and ability to stimulate allogeneic responder cell proliferation, and production of IFN-γ; compared with DC derived from normal human PBMC donors. KG-1 and MUTZ-3 DLC increased expression of CD80, CD83, CD86, and HLA-DR, and MUTZ-3 DLC downregulated CD14 and expressed CD1a. Importantly, both KG-1 and MUTZ-3-derived DLC promoted proliferation of allogeneic responder cells more efficiently than unmodified cells; neither cells incorporated FITC-labeled dextran, but both stimulated IFN-γ production from responding allogeneic CD8+ T cells. Control DC produced from PBMC using the FastDC culture also expressed high levels of critical cell surface ligands and demonstrated good APC function. This paper indicates that functional DLC can be cultured from the AML cell lines KG-1 and MUTZ-3, and FastDC culture generates functional KG-1 DLC.

  13. CCL2 Promotes Colorectal Carcinogenesis by Enhancing Polymorphonuclear Myeloid-Derived Suppressor Cell Population and Function

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    Eunyoung Chun

    2015-07-01

    Full Text Available Our study reveals a non-canonical role for CCL2 in modulating non-macrophage, myeloid-derived suppressor cells (MDSCs and shaping a tumor-permissive microenvironment during colon cancer development. We found that intratumoral CCL2 levels increased in patients with colitis-associated colorectal cancer (CRC, adenocarcinomas, and adenomas. Deletion of CCL2 blocked progression from dysplasia to adenocarcinoma and reduced the number of colonic MDSCs in a spontaneous mouse model of colitis-associated CRC. In a transplantable mouse model of adenocarcinoma and an APC-driven adenoma model, CCL2 fostered MDSC accumulation in evolving colonic tumors and enhanced polymorphonuclear (PMN-MDSC immunosuppressive features. Mechanistically, CCL2 regulated T cell suppression of PMN-MDSCs in a STAT3-mediated manner. Furthermore, CCL2 neutralization decreased tumor numbers and MDSC accumulation and function. Collectively, our experiments support that perturbing CCL2 and targeting MDSCs may afford therapeutic opportunities for colon cancer interception and prevention.

  14. Targeting of the BLT2 in chronic myeloid leukemia inhibits leukemia stem/progenitor cell function

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Meifang; Ai, Hongmei; Li, Tao [Department of Laboratory Medicine, JingZhou Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Jingzhou (China); Rajoria, Pasupati; Shahu, Prakash [Department of Clinical Medicine, Medical School of Yangtze University, Jingzhou (China); Li, Xiansong, E-mail: lixiansongjz@hotmail.com [Department of Neurosurgery, JingZhou Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Jingzhou (China)

    2016-04-15

    Imatinib, a tyrosine kinase inhibitor (TKI) has significantly improved clinical outcome for chronic myeloid leukemia (CML) patients. However, patients develop resistance when the disease progresses to the blast phase (BP) and the mechanisms are not well understood. Here we show that BCR-ABL activates BLT2 in hematopoietic stem/progenitor cells to promote leukemogenesis and this involves the p53 signaling pathway. Compared to normal bone marrow (NBM), the mRNA and protein levels of BLT2 are significantly increased in BP-CML CD34{sup +} stem/progenitor cells. This is correlated with increasing BCR-ABL expression. In contrast, knockdown of BCR-ABL or inhibition of its tyrosine kinase activity decreases Blt2 protein level. BLT2 inhibition induces apoptosis, inhibits proliferation, colony formation and self-renewal capacity of CD34{sup +} cells from TKI-resistant BP-CML patients. Importantly, the inhibitory effects of BCR-ABL TKI on CML stem/progenitor cells are further enhanced upon combination with BLT2 inhibition. We further show that BLT2 activation selectively suppresses p53 but not Wnt or BMP-mediated luciferase activity and transcription. Our results demonstrate that BLT2 is a novel pathway activated by BCR-ABL and critically involved in the resistance of BP-CML CD34{sup +} stem/progenitors to TKIs treatment. Our findings suggest that BLT2 and p53 can serve as therapeutic targets for CML treatment. - Highlights: • BCR-ABL regulates BLT2 expression to promote leukemogenesis. • BLT2 is essential to maintain CML cell function. • Activation of BLT2 suppresses p53 signaling pathway in CML cells. • Inhibition of BLT2 and BCR-ABL synergize in eliminating CML CD34{sup +} stem/progenitors.

  15. Myeloid suppressor cells in cancer and autoimmunity.

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    Sica, Antonio; Massarotti, Marco

    2017-07-17

    A bottleneck for immunotherapy of cancer is the immunosuppressive microenvironment in which the tumor cells proliferate. Cancers harness the immune regulatory mechanism that prevents autoimmunity from evading immunosurveillance and promoting immune destruction. Regulatory T cells, myeloid suppressor cells, inhibitory cytokines and immune checkpoint receptors are the major components of the immune system acting in concert with cancer cells and causing the subversion of anti-tumor immunity. This redundant immunosuppressive network poses an impediment to efficacious immunotherapy by facilitating tumor progression. Tumor-associated myeloid cells comprise heterogeneous populations acting systemically (myeloid-derived suppressor cells/MDSCs) and/or locally in the tumor microenvironment (MDSCs and tumor-associated macrophages/TAMs). Both populations promote cancer cell proliferation and survival, angiogenesis and lymphangiogenesis and elicit immunosuppression through different pathways, including the expression of immunosuppressive cytokines and checkpoint inhibitors. Several evidences have demonstrated that myeloid cells can express different functional programs in response to different microenvironmental signals, a property defined as functional plasticity. The opposed extremes of this functional flexibility are generally represented by the classical macrophage activation, which identifies inflammatory and cytotoxic M1 polarized macrophages, and the alternative state of macrophage activation, which identifies M2 polarized anti-inflammatory and immunosuppressive macrophages. Functional skewing of myeloid cells occurs in vivo under physiological and pathological conditions, including cancer and autoimmunity. Here we discuss how myeloid suppressor cells can on one hand support tumor growth and, on the other, limit autoimmune responses, indicating that their therapeutic reprogramming can generate opportunities in relieving immunosuppression in the tumor microenvironment or

  16. Rho GTPase expression in human myeloid cells.

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    Suzanne F G van Helden

    Full Text Available Myeloid cells are critical for innate immunity and the initiation of adaptive immunity. Strict regulation of the adhesive and migratory behavior is essential for proper functioning of these cells. Rho GTPases are important regulators of adhesion and migration; however, it is unknown which Rho GTPases are expressed in different myeloid cells. Here, we use a qPCR-based approach to investigate Rho GTPase expression in myeloid cells.We found that the mRNAs encoding Cdc42, RhoQ, Rac1, Rac2, RhoA and RhoC are the most abundant. In addition, RhoG, RhoB, RhoF and RhoV are expressed at low levels or only in specific cell types. More differentiated cells along the monocyte-lineage display lower levels of Cdc42 and RhoV, while RhoC mRNA is more abundant. In addition, the Rho GTPase expression profile changes during dendritic cell maturation with Rac1 being upregulated and Rac2 downregulated. Finally, GM-CSF stimulation, during macrophage and osteoclast differentiation, leads to high expression of Rac2, while M-CSF induces high levels of RhoA, showing that these cytokines induce a distinct pattern. Our data uncover cell type specific modulation of the Rho GTPase expression profile in hematopoietic stem cells and in more differentiated cells of the myeloid lineage.

  17. Production and Functional Characterization of Murine Osteoclasts Differentiated from ER-Hoxb8-Immortalized Myeloid Progenitor Cells.

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    Frank Zach

    Full Text Available In vitro differentiation into functional osteoclasts is routinely achieved by incubation of embryonic stem cells, induced pluripotent stem cells, or primary as well as cryopreserved spleen and bone marrow-derived cells with soluble receptor activator of nuclear factor kappa-B ligand and macrophage colony-stimulating factor. Additionally, osteoclasts can be derived from co-cultures with osteoblasts or by direct administration of soluble receptor activator of nuclear factor kappa-B ligand to RAW 264.7 macrophage lineage cells. However, despite their benefits for osteoclast-associated research, these different methods have several drawbacks with respect to differentiation yields, time and animal consumption, storage life of progenitor cells or the limited potential for genetic manipulation of osteoclast precursors. In the present study, we therefore established a novel protocol for the differentiation of osteoclasts from murine ER-Hoxb8-immortalized myeloid stem cells. We isolated and immortalized bone marrow cells from wild type and genetically manipulated mouse lines, optimized protocols for osteoclast differentiation and compared these cells to osteoclasts derived from conventional sources. In vitro generated ER-Hoxb8 osteoclasts displayed typical osteoclast characteristics such as multi-nucleation, tartrate-resistant acid phosphatase staining of supernatants and cells, F-actin ring formation and bone resorption activity. Furthermore, the osteoclast differentiation time course was traced on a gene expression level. Increased expression of osteoclast-specific genes and decreased expression of stem cell marker genes during differentiation of osteoclasts from ER-Hoxb8-immortalized myeloid progenitor cells were detected by gene array and confirmed by semi-quantitative and quantitative RT-PCR approaches. In summary, we established a novel method for the quantitative production of murine bona fide osteoclasts from ER-Hoxb8 stem cells generated from

  18. Applications of myeloid-specific promoters in transgenic mice support in vivo imaging and functional genomics but do not support the concept of distinct macrophage and dendritic cell lineages or roles in immunity.

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    Hume, David A

    2011-04-01

    Myeloid lineage cells contribute to innate and acquired immunity, homeostasis, wound repair, and inflammation. There is considerable interest in manipulation of their function in transgenic mice using myeloid-specific promoters. This review considers the applications and specificity of some of the most widely studied transgenes, driven by promoter elements of the lysM, csf1r, CD11c, CD68, macrophage SRA, and CD11b genes, as well as several others. Transgenes have been used in mice to generate myeloid lineage-specific cell ablation, expression of genes of interest, including fluorescent reporters, or deletion via recombination. In general, the specificity of such transgenes has been overinterpreted, and none of them provide well-documented, reliable, differential expression in any specific myeloid cell subset, macrophages, granulocytes, or myeloid DCs. Nevertheless, they have proved valuable in cell isolation, functional genomics, and live imaging of myeloid cell behavior in many different pathologies.

  19. Development and trafficking function of haematopoietic stem cells and myeloid cells during fetal ontogeny

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    Heinig, Kristina; Sage, Fanny; Robin, Catherine; Sperandio, Markus

    2015-01-01

    Fetal haematopoiesis is a highly regulated process in terms of time and location. It is characterized by the emergence of specific cell populations at different extra-and intraembryonic anatomical sites. Trafficking of haematopoietic stem cells (HSCs) between these supportive niches is regulated by

  20. Development and trafficking function of haematopoietic stem cells and myeloid cells during fetal ontogeny

    NARCIS (Netherlands)

    Heinig, Kristina; Sage, Fanny; Robin, Catherine; Sperandio, Markus

    2015-01-01

    Fetal haematopoiesis is a highly regulated process in terms of time and location. It is characterized by the emergence of specific cell populations at different extra- and intraembryonic anatomical sites. Trafficking of haematopoietic stem cells (HSCs) between these supportive niches is regulated by

  1. Myeloid Cells in Infantile Hemangioma

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    Ritter, Matthew R.; Reinisch, John; Friedlander, Sheila Fallon; Friedlander, Martin

    2006-01-01

    Little is known about the pathogenesis of infantile hemangiomas despite the fact that they are relatively common tumors. These benign neoplasms occur in as many as 1 in 10 births, and although rarely life threatening, hemangiomas can pose serious concerns to the cosmetic and psychosocial development of the afflicted child. Ulceration, scarring, and disfigurement are significant problems as are encroachment of the ear and eye, which can threaten hearing and vision. The precise mechanisms controlling the rapid growth observed in the first months of life and the spontaneous involution that follows throughout the course of years remain unknown. In this report we demonstrate the presence of large numbers of hematopoietic cells of the myeloid lineage in proliferating hemangiomas and propose a mechanism for the observed evolution of these lesions that is triggered by hypoxia and involves the participation of myeloid cells. We report the results of experiments using myeloid markers (CD83, CD32, CD14, CD15) that unexpectedly co-labeled hemangioma endothelial cells, providing new evidence that these cells are distinct from normal endothelium. PMID:16436675

  2. A Novel Function for P2Y2 in Myeloid Recipient-Derived Cells during Graft-versus-Host Disease.

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    Klämbt, Verena; Wohlfeil, Sebastian A; Schwab, Lukas; Hülsdünker, Jan; Ayata, Korcan; Apostolova, Petya; Schmitt-Graeff, Annette; Dierbach, Heide; Prinz, Gabriele; Follo, Marie; Prinz, Marco; Idzko, Marco; Zeiser, Robert

    2015-12-15

    Acute graft-versus-host disease (GvHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation. During the initiation phase of acute GvHD, endogenous danger signals such as ATP are released and inform the innate immune system via activation of the purinergic receptor P2X7 that a noninfectious damage has occurred. A second ATP-activated purinergic receptor involved in inflammatory diseases is P2Y2. In this study, we used P2y2(-/-) mice to test the role of this receptor in GvHD. P2y2(-/-) recipients experienced reduced GvHD-related mortality, IL-6 levels, enterocyte apoptosis, and histopathology scores. Chimeric mice with P2y2 deficiency restricted to hematopoietic tissues survived longer after GvHD induction than did wild-type mice. P2y2 deficiency of the recipient was connected to lower levels of myeloperoxidase in the intestinal tract of mice developing GvHD and a reduced myeloid cell signature. Selective deficiency of P2Y2 in inflammatory monocytes decreased GvHD severity. Mechanistically, P2y2(-/-) inflammatory monocytes displayed defective ERK activation and reactive oxygen species production. Compatible with a role of P2Y2 in human GvHD, the frequency of P2Y2(+) cells in inflamed GvHD lesions correlated with histopathological GvHD severity. Our findings indicate a novel function for P2Y2 in ATP-activated recipient myeloid cells during GvHD, which could be exploited when targeting danger signals to prevent GvHD.

  3. Phenotypic, genotypic, and functional characterization of normal and acute myeloid leukemia-derived marrow endothelial cells.

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    Pizzo, Russell J; Azadniv, Mitra; Guo, Naxin; Acklin, Joshua; Lacagnina, Kimberly; Coppage, Myra; Liesveld, Jane L

    2016-05-01

    In addition to participation in homing, egress, and transmigration of hematopoietic cells, marrow endothelium also contributes to cell proliferation and survival. Endothelial cells from multiple vascular beds are able to prevent spontaneous or therapy-induced apoptosis in acute myelogenous leukemia (AML) blasts. Marrow-derived endothelial cells from leukemia patients have not been well-characterized, and in this work, endothelial cells were purified from marrow aspirates from normal subjects or from newly diagnosed AML patients to compare these cells phenotypically and functionally. By reverse transcription polymerase chain reaction, these cells express CD31, Tie-2, vascular endothelial growth factor (VEGF), and endothelial nitric oxide synthase (eNOS), supporting endothelial origin. They take up acetyl low-density lipoprotein and are able to form tubular structures. Culture of AML cells with endothelial cells from both normal and AML subjects supported adhesion, transmigration, and leukemia colony-forming unit outgrowth. RNA-sequencing analysis revealed 130 genes significantly up- or downregulated in AML-derived endothelial cells as compared with those derived from normal marrow. The genes differentially expressed (p phenotype and function to their normal marrow-derived counterparts, but genomic analysis suggests a differential signature with altered expression of genes, which could play a role in leukemogenesis or leukemia cell maintenance in the marrow microenvironment. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

  4. Indoleamine 2,3 Dioxygenase (IDO) as a Mediator of Myeloid Derived Suppressor Cell Function in Breast Cancer

    Science.gov (United States)

    2009-10-31

    Ronca, R., Serafini , P ., Zam boni, P., Restifo, N. P., and Zanovello, P. Identification of a CD11b(+)/Gr-1(+)/CD31(+) myeloid progenitor capable...of activating or suppressing CD8(+) T cells. Blood, 96: 3838-3846, 2000. 6. Serafini , P., De Santo, C., Marigo, I. , Cingarlini, S., Dolcetti, L

  5. Vitamin D improves endothelial dysfunction and restores myeloid angiogenic cell function via reduced CXCL-10 expression in systemic lupus erythematosus.

    Science.gov (United States)

    Reynolds, John A; Haque, Sahena; Williamson, Kate; Ray, David W; Alexander, M Yvonne; Bruce, Ian N

    2016-03-01

    Patients with systemic lupus erythematosus (SLE) have accelerated cardiovascular disease and dysfunctional endothelial repair mechanisms. Myeloid angiogenic cells (MACs), derived from circulating monocytes, augment vascular repair by paracrine secretion of pro-angiogenic factors. We observed that SLE MACs are dysfunctional and secrete pro-inflammatory cytokines. We also found that the vitamin D receptor was transiently expressed during MAC differentiation and that in vitro, calcitriol increased differentiation of monocytes into MACs in both SLE and in a model using the prototypic SLE cytokine, interferon-alpha. The active form of vitamin D (calcitriol) restored the SLE MAC phenotype towards that of healthy subjects with reduced IL-6 secretion, and normalised surface marker expression. Calcitriol also augmented the angiogenic capacity of MACs via the down-regulation of CXCL-10. In SLE patients treated with cholecalciferol for 12 weeks, the improvement in endothelial function correlated with increase in serum 25(OH)D concentrations independently of disease activity. We also show that MACs were able to positively modulate eNOS expression in human endothelial cells in vitro, an effect further enhanced by calcitriol treatment of SLE MACs. The results demonstrate that vitamin D can positively modify endothelial repair mechanisms and thus endothelial function in a population with significant cardiovascular risk.

  6. Cytomegalovirus immune evasion of myeloid lineage cells.

    Science.gov (United States)

    Brinkmann, Melanie M; Dağ, Franziska; Hengel, Hartmut; Messerle, Martin; Kalinke, Ulrich; Čičin-Šain, Luka

    2015-06-01

    Cytomegalovirus (CMV) evades the immune system in many different ways, allowing the virus to grow and its progeny to spread in the face of an adverse environment. Mounting evidence about the antiviral role of myeloid immune cells has prompted the research of CMV immune evasion mechanisms targeting these cells. Several cells of the myeloid lineage, such as monocytes, dendritic cells and macrophages, play a role in viral control, but are also permissive for CMV and are naturally infected by it. Therefore, CMV evasion of myeloid cells involves mechanisms that qualitatively differ from the evasion of non-CMV-permissive immune cells of the lymphoid lineage. The evasion of myeloid cells includes effects in cis, where the virus modulates the immune signaling pathways within the infected myeloid cell, and those in trans, where the virus affects somatic cells targeted by cytokines released from myeloid cells. This review presents an overview of CMV strategies to modulate and evade the antiviral activity of myeloid cells in cis and in trans.

  7. Hypoxia inducible factors are dispensable for myeloid cell migration into the inflamed mouse eye

    Science.gov (United States)

    Gardner, Peter J.; Liyanage, Sidath E.; Cristante, Enrico; Sampson, Robert D.; Dick, Andrew D.; Ali, Robin R.; Bainbridge, James W.

    2017-01-01

    Hypoxia inducible factors (HIFs) are ubiquitously expressed transcription factors important for cell homeostasis during dynamic oxygen levels. Myeloid specific HIFs are crucial for aspects of myeloid cell function, including their ability to migrate into inflamed tissues during autoimmune disease. This contrasts with the concept that accumulation of myeloid cells at ischemic and hypoxic sites results from a lack of chemotactic responsiveness. Here we seek to address the role of HIFs in myeloid trafficking during inflammation in a mouse model of human uveitis. We show using mice with myeloid-specific Cre-deletion of HIFs that myeloid HIFs are dispensable for leukocyte migration into the inflamed eye. Myeloid-specific deletion of Hif1a, Epas1, or both together, had no impact on the number of myeloid cells migrating into the eye. Additionally, stabilization of HIF pathways via deletion of Vhl in myeloid cells had no impact on myeloid trafficking into the inflamed eye. Finally, we chemically induce hypoxemia via hemolytic anemia resulting in HIF stabilization within circulating leukocytes to demonstrate the dispensable role of HIFs in myeloid cell migration into the inflamed eye. These data suggest, contrary to previous reports, that HIF pathways in myeloid cells during inflammation and hypoxia are dispensable for myeloid cell tissue trafficking. PMID:28112274

  8. Regulator of myeloid differentiation and function:The secret life of Ikaros

    Institute of Scientific and Technical Information of China (English)

    Olivia; L; Francis; Jonathon; L; Payne; Kimberly; J; Payne

    2011-01-01

    Ikaros (also known as Lyf-1) was initially described as a lymphoid-specific transcription factor.Although Ikaros has been shown to regulate hematopoietic stem cell renewal,as well as the development and function of cells from multiple hematopoietic lineages,including the myeloid lineage,Ikaros has primarily been studied in context of lymphoid development and malignancy.This review focuses on the role of Ikaros in myeloid cells.We address the importance of post-transcriptional regulation of Ikaros function;the emerging role of Ikaros in myeloid malignancy;Ikaros as a regulator of myeloid differentiation and function;and the selective expression of Ikaros isoform-x in cells with myeloid potential.We highlight the challenges of dissecting Ikaros function in lineage commitment decisions among lymphoidmyeloid progenitors that have emerged as a major myeloid differentiation pathway in recent studies,which leads to reconstruction of the traditional map of murine and human hematopoiesis.

  9. Myeloid-derived suppressor cell function is reduced by Withaferin A, a potent and abundant component of Withania somnifera root extract.

    Science.gov (United States)

    Sinha, Pratima; Ostrand-Rosenberg, Suzanne

    2013-11-01

    Myeloid cells play a crucial role in tumor progression. The most common tumor-infiltrating myeloid cells are myeloid-derived suppressor cells (MDSC) and tumor-associated macrophages (TAMs). These cells promote tumor growth by their inherent immune suppressive activity which is enhanced by their cross-talk. The root extract of the plant Withania somnifera (Ashwagandha) (WRE) has been reported to reduce tumor growth. HPLC analysis identified Withaferin A (WA) as the most abundant constituent of WRE and led us to determine whether the anti-tumor effects of WRE and WA involve modulating MDSC and TAM activity. A prominent effect of MDSC is their production of IL-10 which increases upon cross-talk with macrophages, thus polarizing immunity to a pro-tumor type 2 phenotype. In vitro treatment with WA decreased MDSC production of IL-10 and prevented additional MDSC production of IL-10 generated by MDSC-macrophage cross-talk. Macrophage secretion of IL-6 and TNFα, cytokines that increase MDSC accumulation and function, was also reduced by in vitro treatment with WA. Much of the T-cell suppressive activity of MDSC is due to MDSC production of reactive oxygen species (ROS), and WA significantly reduced MDSC production of ROS through a STAT3-dependent mechanism. In vivo treatment of tumor-bearing mice with WA decreased tumor weight, reduced the quantity of granulocytic MDSC, and reduced the ability of MDSC to suppress antigen-driven activation of CD4+ and CD8+ T cells. Thus, adjunctive treatment with WA reduced myeloid cell-mediated immune suppression, polarized immunity toward a tumor-rejecting type 1 phenotype, and may facilitate the development of anti-tumor immunity.

  10. Measurement of myeloid cell immune suppressive activity.

    Science.gov (United States)

    Dolcetti, Luigi; Peranzoni, Elisa; Bronte, Vincenzo

    2010-11-01

    This unit presents simple methods to assess the immunosuppressive properties of immunoregulatory cells of myeloid origin, such as myeloid-derived suppressor cells (MDSCs), both in vitro and in vivo. These methods are general and could be adapted to test the impact of different suppressive populations on T cell activation, proliferation, and cytotoxic activity; moreover they could be useful to assess the influence exerted on immune suppressive pathways by genetic modifications, chemical inhibitors, and drugs.

  11. Loss of IKKβ but Not NF-κB p65 Skews Differentiation towards Myeloid over Erythroid Commitment and Increases Myeloid Progenitor Self-Renewal and Functional Long-Term Hematopoietic Stem Cells.

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    Full Text Available NF-κB is an important regulator of both differentiation and function of lineage-committed hematopoietic cells. Targeted deletion of IκB kinase (IKK β results in altered cytokine signaling and marked neutrophilia. To investigate the role of IKKβ in regulation of hematopoiesis, we employed Mx1-Cre mediated IKKβ conditional knockout mice. As previously reported, deletion of IKKβ in hematopoietic cells results in neutrophilia, and we now also noted decreased monocytes and modest anemia. Granulocyte-macrophage progenitors (GMPs accumulated markedly in bone marrow of IKKβ deleted mice whereas the proportion and number of megakaryocyte-erythrocyte progenitors (MEP decreased. Accordingly, we found a significantly reduced frequency of proerythroblasts and basophilic and polychromatic erythroblasts, and IKKβ-deficient bone marrow cells yielded a significantly decreased number of BFU-E compared to wild type. These changes are associated with elevated expression of C/EBPα, Gfi1, and PU.1 and diminished Gata1, Klf1, and SCL/Tal1 in IKKβ deficient Lineage-Sca1+c-Kit+ (LSK cells. In contrast, no effect on erythropoiesis or expression of lineage-related transcription factors was found in marrow lacking NF-κB p65. Bone marrow from IKKβ knockout mice has elevated numbers of phenotypic long and short term hematopoietic stem cells (HSC. A similar increase was observed when IKKβ was deleted after marrow transplantation into a wild type host, indicating cell autonomous expansion. Myeloid progenitors from IKKβ- but not p65-deleted mice demonstrate increased serial replating in colony-forming assays, indicating increased cell autonomous self-renewal capacity. In addition, in a competitive repopulation assay deletion of IKKβ resulted in a stable advantage of bone marrow derived from IKKβ knockout mice. In summary, loss of IKKβ resulted in significant effects on hematopoiesis not seen upon NF-κB p65 deletion. These include increased myeloid and reduced

  12. Lack of autophagy in the hematopoietic system leads to loss of hematopoietic stem cell function and dysregulated myeloid proliferation.

    Science.gov (United States)

    Mortensen, Monika; Watson, Alexander Scarth; Simon, Anna Katharina

    2011-09-01

    The regulated lysosomal degradation pathway of autophagy prevents cellular damage and thus protects from malignant transformation. Autophagy is also required for the maturation of various hematopoietic lineages, namely the erythroid and lymphoid ones, yet its role in adult hematopoietic stem cells (HSCs) remained unexplored. While normal HSCs sustain life-long hematopoiesis, malignant transformation of HSCs or early progenitors leads to leukemia. Mechanisms protecting HSCs from cellular damage are therefore essential to prevent hematopoietic malignancies. By conditionally deleting the essential autophagy gene Atg7 in the hematopoietic system, we found that autophagy is required for the maintenance of true HSCs and therefore also of downstream hematopoietic progenitors. Loss of autophagy in HSCs leads to the expansion of a progenitor cell population in the bone marrow, giving rise to a severe, invasive myeloproliferation, which strongly resembles human acute myeloid leukemia (AML).

  13. Identification and functional characterization of the miRNA-gene regulatory network in chronic myeloid leukemia lineage negative cells

    Science.gov (United States)

    Agatheeswaran, S.; Pattnayak, N. C.; Chakraborty, S.

    2016-09-01

    Chronic myeloid leukemia (CML) is maintained by leukemic stem cells (LSCs) which are resistant to the existing TKI therapy. Hence a better understanding of the CML LSCs is necessary to eradicate these cells and achieve complete cure. Using the miRNA-gene interaction networks from the CML lin(-) cells we identified a set of up/down-regulated miRNAs and corresponding target genes. Association studies (Pearson correlation) from the miRNA and gene expression data showed that miR-1469 and miR-1972 have significantly higher number of target genes, 75 and 50 respectively. We observed that miR-1972 induces G2-M cell cycle arrest and miR-1469 moderately arrested G1 cell cycle when overexpressed in KCL22 cells. We have earlier shown that a combination of imatinib and JAK inhibitor I can significantly bring down the proliferation of CML lineage negative cells. Here we observed that imatinib and JAK inhibitor I combination restored the expression pattern of the down-regulated miRNAs in primary CML lin(-) cells. Thus effective manipulation of the deregulated miRNAs can restore the miRNA-mRNA networks that can efficiently inhibit CML stem and progenitor cells and alleviate the disease.

  14. Transforming Growth Factor-Beta and Matrix Metalloproteinases: Functional Interactions in Tumor Stroma-Infiltrating Myeloid Cells

    Science.gov (United States)

    Santibanez, Juan F.

    2014-01-01

    Transforming growth factor-beta (TGF-β) is a pleiotropic factor with several different roles in health and disease. In tumorigenesis, it may act as a protumorigenic factor and have a profound impact on the regulation of the immune system response. Matrix metalloproteinases (MMPs) are a family that comprises more than 25 members, which have recently been proposed as important regulators acting in tumor stroma by regulating the response of noncellular and cellular microenvironment. Tumor stroma consists of several types of resident cells and infiltrating cells derived from bone marrow, which together play crucial roles in the promotion of tumor growth and metastasis. In cancer cells, TGF-β regulates MMPs expression, while MMPs, produced by either cancer cells or residents' stroma cells, activate latent TGF-β in the extracellular matrix, together facilitating the enhancement of tumor progression. In this review we will focus on the compartment of myeloid stroma cells, such as tumor-associated macrophages, neutrophils, and dendritic and mast cells, which are potently regulated by TGF-β and produce large amounts of MMPs. Their interplay and mutual implications in the generation of pro-tumorigenic cancer microenvironment will be analyzed. PMID:24578639

  15. Transforming Growth Factor-Beta and Matrix Metalloproteinases: Functional Interactions in Tumor Stroma-Infiltrating Myeloid Cells

    Directory of Open Access Journals (Sweden)

    Jelena Krstic

    2014-01-01

    Full Text Available Transforming growth factor-beta (TGF-β is a pleiotropic factor with several different roles in health and disease. In tumorigenesis, it may act as a protumorigenic factor and have a profound impact on the regulation of the immune system response. Matrix metalloproteinases (MMPs are a family that comprises more than 25 members, which have recently been proposed as important regulators acting in tumor stroma by regulating the response of noncellular and cellular microenvironment. Tumor stroma consists of several types of resident cells and infiltrating cells derived from bone marrow, which together play crucial roles in the promotion of tumor growth and metastasis. In cancer cells, TGF-β regulates MMPs expression, while MMPs, produced by either cancer cells or residents’ stroma cells, activate latent TGF-β in the extracellular matrix, together facilitating the enhancement of tumor progression. In this review we will focus on the compartment of myeloid stroma cells, such as tumor-associated macrophages, neutrophils, and dendritic and mast cells, which are potently regulated by TGF-β and produce large amounts of MMPs. Their interplay and mutual implications in the generation of pro-tumorigenic cancer microenvironment will be analyzed.

  16. Arginine Metabolism in Myeloid Cells Shapes Innate and Adaptive Immunity

    Science.gov (United States)

    Rodriguez, Paulo C.; Ochoa, Augusto C.; Al-Khami, Amir A.

    2017-01-01

    Arginine metabolism has been a key catabolic and anabolic process throughout the evolution of the immune response. Accruing evidence indicates that arginine-catabolizing enzymes, mainly nitric oxide synthases and arginases, are closely integrated with the control of immune response under physiological and pathological conditions. Myeloid cells are major players that exploit the regulators of arginine metabolism to mediate diverse, although often opposing, immunological and functional consequences. In this article, we focus on the importance of arginine catabolism by myeloid cells in regulating innate and adaptive immunity. Revisiting this matter could result in novel therapeutic approaches by which the immunoregulatory nodes instructed by arginine metabolism can be targeted.

  17. Roles Nrf2 Plays in Myeloid Cells and Related Disorders

    Directory of Open Access Journals (Sweden)

    Eri Kobayashi

    2013-01-01

    Full Text Available The Keap1-Nrf2 system protects animals from oxidative and electrophilic stresses. Nrf2 is a transcription factor that induces the expression of genes essential for detoxifying reactive oxygen species (ROS and cytotoxic electrophiles. Keap1 is a stress sensor protein that binds to and ubiquitinates Nrf2 under unstressed conditions, leading to the rapid proteasomal degradation of Nrf2. Upon exposure to stress, Keap1 is modified and inactivated, which allows Nrf2 to accumulate and activate the transcription of a battery of cytoprotective genes. Antioxidative and detoxification activities are important for many types of cells to avoid DNA damage and cell death. Accumulating lines of recent evidence suggest that Nrf2 is also required for the primary functions of myeloid cells, which include phagocytosis, inflammation regulation, and ROS generation for bactericidal activities. In fact, results from several mouse models have shown that Nrf2 expression in myeloid cells is required for the proper regulation of inflammation, antitumor immunity, and atherosclerosis. Moreover, several molecules generated upon inflammation activate Nrf2. Although ROS detoxification mediated by Nrf2 is assumed to be required for anti-inflammation, the entire picture of the Nrf2-mediated regulation of myeloid cell primary functions has yet to be elucidated. In this review, we describe the Nrf2 inducers characteristic of myeloid cells and the contributions of Nrf2 to diseases.

  18. Inhibition of breast cancer resistance protein (ABCG2 in human myeloid dendritic cells induces potent tolerogenic functions during LPS stimulation.

    Directory of Open Access Journals (Sweden)

    Jun-O Jin

    Full Text Available Breast cancer resistance protein (ABCG2, a member of the ATP-binding cassette transporters has been identified as a major determinant of multidrug resistance (MDR in cancer cells, but ABC transporter inhibition has limited therapeutic value in vivo. In this research, we demonstrated that inhibition of efflux transporters ABCG2 induced the generation of tolerogenic DCs from human peripheral blood myeloid DCs (mDCs. ABCG2 expression was present in mDCs and was further increased by LPS stimulation. Treatment of CD1c+ mDCs with an ABCG2 inhibitor, Ko143, during LPS stimulation caused increased production of IL-10 and decreased production of pro-inflammatory cytokines and decreased expression of CD83 and CD86. Moreover, inhibition of ABCG2 in monocyte-derived DCs (MDDCs abrogated the up-regulation of co-stimulatory molecules and production of pro-inflammatory cytokines in these cells in response to LPS. Furthermore, CD1c+ mDCs stimulated with LPS plus Ko143 inhibited the proliferation of allogeneic and superantigen-specific syngenic CD4+ T cells and promoted expansion of CD25+FOXP3+ regulatory T (Treg cells in an IL-10-dependent fashion. These tolerogenic effects of ABCG2 inhibition could be abolished by ERK inhibition. Thus, we demonstrated that inhibition of ABCG2 in LPS-stimulated mDCs can potently induce tolerogenic potentials in these cells, providing crucial new information that could lead to development of better strategies to combat MDR cancer.

  19. Myeloid Cell-Specific Knockout of NFI-A Improves Sepsis Survival.

    Science.gov (United States)

    McPeak, Melissa B; Youssef, Dima; Williams, Danielle A; Pritchett, Christopher; Yao, Zhi Q; McCall, Charles E; El Gazzar, Mohamed

    2017-04-01

    Myeloid progenitor-derived suppressor cells (MDSCs) arise from myeloid progenitors and suppress both innate and adaptive immunity. MDSCs expand during the later phases of sepsis in mice, promote immunosuppression, and reduce survival. Here, we report that the myeloid differentiation-related transcription factor nuclear factor I-A (NFI-A) controls MDSC expansion during sepsis and impacts survival. Unlike MDSCs, myeloid cells with conditional deletion of the Nfia gene normally differentiated into effector cells during sepsis, cleared infecting bacteria, and did not express immunosuppressive mediators. In contrast, ectopic expression of NFI-A in myeloid progenitors from NFI-A myeloid cell-deficient mice impeded myeloid cell maturation and promoted immune repressor function. Importantly, surviving septic mice with conditionally deficient NFI-A myeloid cells were able to respond to challenge with bacterial endotoxin by mounting an acute inflammatory response. Together, these results support the concept of NFI-A as a master molecular transcriptome switch that controls myeloid cell differentiation and maturation and that malfunction of this switch during sepsis promotes MDSC expansion that adversely impacts sepsis outcome. Copyright © 2017 American Society for Microbiology.

  20. Bone marrow myeloid cells in regulation of multiple myeloma progression.

    Science.gov (United States)

    Herlihy, Sarah E; Lin, Cindy; Nefedova, Yulia

    2017-08-01

    Survival, growth, and response to chemotherapy of cancer cells depends strongly on the interaction of cancer cells with the tumor microenvironment. In multiple myeloma, a cancer of plasma cells that localizes preferentially in the bone marrow, the microenvironment is highly enriched with myeloid cells. The majority of myeloid cells are represented by mature and immature neutrophils. The contribution of the different myeloid cell populations to tumor progression and chemoresistance in multiple myeloma is discussed.

  1. Dendritic cell-based immunotherapy for myeloid leukemias.

    Science.gov (United States)

    Schürch, Christian M; Riether, Carsten; Ochsenbein, Adrian F

    2013-12-31

    Acute and chronic myeloid leukemia (AML, CML) are hematologic malignancies arising from oncogene-transformed hematopoietic stem/progenitor cells known as leukemia stem cells (LSCs). LSCs are selectively resistant to various forms of therapy including irradiation or cytotoxic drugs. The introduction of tyrosine kinase inhibitors has dramatically improved disease outcome in patients with CML. For AML, however, prognosis is still quite dismal. Standard treatments have been established more than 20 years ago with only limited advances ever since. Durable remission is achieved in less than 30% of patients. Minimal residual disease (MRD), reflected by the persistence of LSCs below the detection limit by conventional methods, causes a high rate of disease relapses. Therefore, the ultimate goal in the treatment of myeloid leukemia must be the eradication of LSCs. Active immunotherapy, aiming at the generation of leukemia-specific cytotoxic T cells (CTLs), may represent a powerful approach to target LSCs in the MRD situation. To fully activate CTLs, leukemia antigens have to be successfully captured, processed, and presented by mature dendritic cells (DCs). Myeloid progenitors are a prominent source of DCs under homeostatic conditions, and it is now well established that LSCs and leukemic blasts can give rise to "malignant" DCs. These leukemia-derived DCs can express leukemia antigens and may either induce anti-leukemic T cell responses or favor tolerance to the leukemia, depending on co-stimulatory or -inhibitory molecules and cytokines. This review will concentrate on the role of DCs in myeloid leukemia immunotherapy with a special focus on their generation, application, and function and how they could be improved in order to generate highly effective and specific anti-leukemic CTL responses. In addition, we discuss how DC-based immunotherapy may be successfully integrated into current treatment strategies to promote remission and potentially cure myeloid leukemias.

  2. Dendritic cell-based immunotherapy for myeloid leukemias

    Directory of Open Access Journals (Sweden)

    Christian Martijn Schürch

    2013-12-01

    Full Text Available Acute and chronic myeloid leukemia (AML, CML are hematologic malignancies arising from oncogene-transformed hematopoietic stem/progenitor cells known as leukemia stem cells (LSCs. LSCs are selectively resistant to various forms of therapy including irradiation or cytotoxic drugs. The introduction of tyrosine kinase inhibitors has dramatically improved disease outcome in patients with CML. For AML, however, prognosis is still quite dismal. Standard treatments have been established more than 20 years ago with only limited advances ever since. Durable remission is achieved in less than 30% of patients. Minimal residual disease (MRD, reflected by the persistence of LSCs below the detection limit by conventional methods, causes a high rate of disease relapses. Therefore, the ultimate goal in the treatment of myeloid leukemia must be the eradication of LSCs. Active immunotherapy, aiming at the generation of leukemia-specific cytotoxic T cells (CTLs, may represent a powerful approach to target LSCs in the MRD situation. To fully activate CTLs, leukemia antigens have to be successfully captured, processed and presented by mature dendritic cells (DCs. Myeloid progenitors are a prominent source of DCs under homeostatic conditions, and it is now well established that LSCs and leukemic blasts can give rise to malignant DCs. These leukemia-derived DCs can express leukemia antigens and may either induce anti-leukemic T cell responses or favor tolerance to the leukemia, depending on co-stimulatory or -inhibitory molecules and cytokines. This review will concentrate on the role of DCs in myeloid leukemia immunotherapy with a special focus on their generation, application and function and how they could be improved in order to generate highly effective and specific anti-leukemic CTL responses. In addition, we discuss how DC-based immunotherapy may be successfully integrated into current treatment strategies to promote remission and potentially cure myeloid

  3. Blast-derived microvesicles in sera from patients with acute myeloid leukemia suppress natural killer cell function via membrane-associated transforming growth factor-beta1.

    Science.gov (United States)

    Szczepanski, Miroslaw J; Szajnik, Marta; Welsh, Ann; Whiteside, Theresa L; Boyiadzis, Michael

    2011-09-01

    Natural killer cell cytotoxicity is decreased in patients with acute myeloid leukemia in comparison to that in normal controls. Tumor-derived microvesicles present in patients' sera exert detrimental effects on immune cells and may influence tumor progression. We investigated the microvesicle protein level, molecular profile and suppression of natural killer cell activity in patients with newly diagnosed acute myeloid leukemia. The patients' sera contained higher levels of microvesicles compared to the levels in controls (Pmicrovesicles had a distinct molecular profile: in addition to conventional microvesicle markers, they contained membrane-associated transforming growth factor-β1, MICA/MICB and myeloid blasts markers, CD34, CD33 and CD117. These microvesicles decreased natural killer cell cytotoxicity (Pmicrovesicles further increased the levels of this protein. Neutralizing anti-transforming growth factor-β1 antibodies inhibited microvesicle-mediated suppression of natural killer cell activity and NKG2D down-regulation. Interleukin-15 protected natural killer cells from adverse effects of tumor-derived microvesicles. We provide evidence for the existence in acute myeloid leukemia of a novel mechanism of natural killer cell suppression mediated by tumor-derived microvesicles and for the ability of interleukin-15 to counteract this suppression.

  4. Blast-derived microvesicles in sera from patients with acute myeloid leukemia suppress natural killer cell function via membrane-associated transforming growth factor-β1

    Science.gov (United States)

    Szczepanski, Miroslaw J.; Szajnik, Marta; Welsh, Ann; Whiteside, Theresa L.; Boyiadzis, Michael

    2011-01-01

    Background Natural killer cell cytotoxicity is decreased in patients with acute myeloid leukemia in comparison to that in normal controls. Tumor-derived microvesicles present in patients’ sera exert detrimental effects on immune cells and may influence tumor progression. Design and Methods We investigated the microvesicle protein level, molecular profile and suppression of natural killer cell activity in patients with newly diagnosed acute myeloid leukemia. Results The patients’ sera contained higher levels of microvesicles compared to the levels in controls (Pmicrovesicles had a distinct molecular profile: in addition to conventional microvesicle markers, they contained membrane-associated transforming growth factor-β1, MICA/MICB and myeloid blasts markers, CD34, CD33 and CD117. These microvesicles decreased natural killer cell cytotoxicity (Pmicrovesicles further increased the levels of this protein. Neutralizing anti-transforming growth factor-β1 antibodies inhibited microvesicle-mediated suppression of natural killer cell activity and NKG2D down-regulation. Interleukin-15 protected natural killer cells from adverse effects of tumor-derived microvesicles. Conclusions We provide evidence for the existence in acute myeloid leukemia of a novel mechanism of natural killer cell suppression mediated by tumor-derived microvesicles and for the ability of interleukin-15 to counteract this suppression. PMID:21606166

  5. DC generation from peripheral blood mononuclear cells in patients with chronic myeloid leukemia: Influence of interferons on DC yield and functional properties.

    Science.gov (United States)

    Flörcken, Anne; Kopp, Joachim; Kölsch, Uwe; Meisel, Christian; Dörken, Bernd; Pezzutto, Antonio; Westermann, Jörg

    2016-05-03

    In Chronic Myeloid Leukemia (CML), standard treatment consists of modern tyrosine-kinase inhibitors (TKI). Nevertheless, there is evidence that immune responses against leukemia-associated antigens (LAA) may play an important role in disease control. Dendritic cell (DC)- based immunotherapy is able to induce T cell responses against LAA and might therefore pose an interesting therapeutic option in CML, especially in the setting of minimal residual disease (MRD). GMP production of DC for clinical vaccination remains a time- and cost- intensive procedure and standardized DC generation is warranted. We asked whether maturation-induction with IFN-γ and IFN-α has an influence on functional properties of DC derived from peripheral blood mononuclear cells (PBMC) in CML patients. Monocyte-derived DC from healthy donors and from patients with CML were analyzed after maturation-induction with our TNF-α-containing standard cytokine cocktail with or without addition of IFN-α and/or IFN-γ. Our results confirm that the addition of IFN-γ leads to enhanced IL-12 secretion in healthy donors. In contrast, in CML patients, IFN-γ was not able to increase IL-12 secretion, possibly due to a higher degree of cell adherence and lower cell yield during the cell culture. Our data suggest, that- in contrast to healthy donors-, additional interferons are not beneficial for maturation induction during large-scale DC production in patients with CML.

  6. Myeloid-derived suppressor cell heterogeneity in human cancers.

    Science.gov (United States)

    Solito, Samantha; Marigo, Ilaria; Pinton, Laura; Damuzzo, Vera; Mandruzzato, Susanna; Bronte, Vincenzo

    2014-06-01

    The dynamic interplay between cancer and host immune system often affects the process of myelopoiesis. As a consequence, tumor-derived factors sustain the accumulation and functional differentiation of myeloid cells, including myeloid-derived suppressor cells (MDSCs), which can interfere with T cell-mediated responses. Since both the phenotype and mechanisms of action of MDSCs appear to be tumor-dependent, it is important not only to determine the presence of all MDSC subsets in each cancer patient, but also which MDSC subsets have clinical relevance in each tumor environment. In this review, we describe the differences between MDSC populations expanded within different tumor contexts and evaluate the prognostic significance of MDSC expansion in peripheral blood and within tumor masses of neoplastic patients.

  7. Myeloid-derived suppressor cell heterogeneity and subset definition.

    Science.gov (United States)

    Peranzoni, Elisa; Zilio, Serena; Marigo, Ilaria; Dolcetti, Luigi; Zanovello, Paola; Mandruzzato, Susanna; Bronte, Vincenzo

    2010-04-01

    Myeloid derived suppressor cells (MDSCs) are defined in mice on the basis of CD11b and Gr-1 marker expression and the functional ability to inhibit T lymphocyte activation. Nevertheless the term 'heterogeneous' remains the first, informal feature commonly attributed to this population. It is clear that CD11b(+)Gr-1(+) cells are part of a myeloid macropopulation, which comprises at least two subsets of polymorphonuclear and monocytic cells with different immunosuppressive properties. While recent literature shows substantial agreement on the immunoregulatory property of the monocytic MDSC subset, there is still contrasting evidence on the role of the granulocytic fraction. Moreover, this dichotomy holds true for human MDSCs. We attempt here to summarize conflicting findings in the field and provide some possible, unifying explanations.

  8. Clinical reagents of GM-CSF and IFN-α induce the generation of functional chronic myeloid leukemia dendritic cells in vitro.

    Science.gov (United States)

    Weng, Kaizhi; Xie, Xiaobao; Qiu, Guoqiang; Gu, Weiying

    2012-01-01

    Dendritic cells (DCs) have been successfully induced in vitro from chronic myeloid leukemia (CML) cells, which may provide a promising immunotherapeutic protocol for CML. To facilitate the optimization of DCs-based vaccination protocols, we investigated the efficiency of in vitro generation of DCs from bone marrow mononuclear cells of CML patients by clinical reagents of GM-CSF and IFN-α. Bone marrow mononuclear cells were isolated from eight CML patients and CML-DCs were generated in the presence of different cytokines (Group A: GM-CSF for research and IL-4 for research; Group B: GM-CSF for injection and IFN-α for injection) in RMPI-1640 medium containing 10% human AB serum. After 8 days, the morphologic features of CML-DCs were observed and their immunophenotypes were analyzed by flow cytometry. The activity of CML-DCs was determined by evaluating their ability to stimulate allogeneic mixed lymphocyte reaction (allo-MLR) and anti-leukemic cytotoxic T lymphocytes (CTLs). The culture protocols were successful in generating functional CML-DCs from all the CML patients as evidenced by the significant upregulation of CD80, CD86, CD83 HLA-DR and CD1a compared to pre-cultured (p cell stimulating proliferation capacity (p protocols for CML patients.

  9. Myeloid cells in tumour-immune interactions.

    Science.gov (United States)

    Kareva, Irina; Berezovskaya, Faina; Castillo-Chavez, Carlos

    2010-07-01

    Despite highly developed specific immune responses, tumour cells often manage to escape recognition by the immune system, continuing to grow uncontrollably. Experimental work suggests that mature myeloid cells may be central to the activation of the specific immune response. Recognition and subsequent control of tumour growth by the cells of the specific immune response depend on the balance between immature (ImC) and mature (MmC) myeloid cells in the body. However, tumour cells produce cytokines that inhibit ImC maturation, altering the balance between ImC and MmC. Hence, the focus of this manuscript is on the study of the potential role of this inhibiting mechanism on tumour growth dynamics. A conceptual predator-prey type model that incorporates the dynamics and interactions of tumour cells, CD8(+) T cells, ImC and MmC is proposed in order to address the role of this mechanism. The prey (tumour) has a defence mechanism (blocking the maturation of ImC) that prevents the predator (immune system) from recognizing it. The model, a four-dimensional nonlinear system of ordinary differential equations, is reduced to a two-dimensional system using time-scale arguments that are tied to the maturation rate of ImC. Analysis shows that the model is capable of supporting biologically reasonable patterns of behaviour depending on the initial conditions. A range of parameters, where healing without external influences can occur, is identified both qualitatively and quantitatively.

  10. Correlation between myeloid-derived suppressor cells and gastric cancer begin with chronic gastritis

    Institute of Scientific and Technical Information of China (English)

    朱立宁

    2012-01-01

    Objective To investigate the correlation between the ratio change of circulating myeloid-derived suppressor cells(MDSCs) and cellular immune function in healthy volunteers,chronic gastritis patients,gastric intraepithelial neoplasia patients and gastric cancer patients

  11. Myeloid cells contribute to tumor lymphangiogenesis.

    Science.gov (United States)

    Zumsteg, Adrian; Baeriswyl, Vanessa; Imaizumi, Natsuko; Schwendener, Reto; Rüegg, Curzio; Christofori, Gerhard

    2009-09-17

    The formation of new blood vessels (angiogenesis) and lymphatic vessels (lymphangiogenesis) promotes tumor outgrowth and metastasis. Previously, it has been demonstrated that bone marrow-derived cells (BMDC) can contribute to tumor angiogenesis. However, the role of BMDC in lymphangiogenesis has largely remained elusive. Here, we demonstrate by bone marrow transplantation/reconstitution and genetic lineage-tracing experiments that BMDC integrate into tumor-associated lymphatic vessels in the Rip1Tag2 mouse model of insulinoma and in the TRAMP-C1 prostate cancer transplantation model, and that the integrated BMDC originate from the myelomonocytic lineage. Conversely, pharmacological depletion of tumor-associated macrophages reduces lymphangiogenesis. No cell fusion events are detected by genetic tracing experiments. Rather, the phenotypical conversion of myeloid cells into lymphatic endothelial cells and their integration into lymphatic structures is recapitulated in two in vitro tube formation assays and is dependent on fibroblast growth factor-mediated signaling. Together, the results reveal that myeloid cells can contribute to tumor-associated lymphatic vessels, thus extending the findings on the previously reported role of hematopoietic cells in lymphatic vessel formation.

  12. Myeloid cells contribute to tumor lymphangiogenesis.

    Directory of Open Access Journals (Sweden)

    Adrian Zumsteg

    Full Text Available The formation of new blood vessels (angiogenesis and lymphatic vessels (lymphangiogenesis promotes tumor outgrowth and metastasis. Previously, it has been demonstrated that bone marrow-derived cells (BMDC can contribute to tumor angiogenesis. However, the role of BMDC in lymphangiogenesis has largely remained elusive. Here, we demonstrate by bone marrow transplantation/reconstitution and genetic lineage-tracing experiments that BMDC integrate into tumor-associated lymphatic vessels in the Rip1Tag2 mouse model of insulinoma and in the TRAMP-C1 prostate cancer transplantation model, and that the integrated BMDC originate from the myelomonocytic lineage. Conversely, pharmacological depletion of tumor-associated macrophages reduces lymphangiogenesis. No cell fusion events are detected by genetic tracing experiments. Rather, the phenotypical conversion of myeloid cells into lymphatic endothelial cells and their integration into lymphatic structures is recapitulated in two in vitro tube formation assays and is dependent on fibroblast growth factor-mediated signaling. Together, the results reveal that myeloid cells can contribute to tumor-associated lymphatic vessels, thus extending the findings on the previously reported role of hematopoietic cells in lymphatic vessel formation.

  13. An Immature Myeloid/Myeloid-Suppressor Cell Response Associated with Necrotizing Inflammation Mediates Lethal Pulmonary Tularemia.

    Science.gov (United States)

    Periasamy, Sivakumar; Avram, Dorina; McCabe, Amanda; MacNamara, Katherine C; Sellati, Timothy J; Harton, Jonathan A

    2016-03-01

    Inhalation of Francisella tularensis (Ft) causes acute and fatal pneumonia. The lung cytokine milieu favors exponential Ft replication, but the mechanisms underlying acute pathogenesis and death remain unknown. Evaluation of the sequential and systemic host immune response in pulmonary tularemia reveals that in contrast to overwhelming bacterial burden or cytokine production, an overt innate cellular response to Ft drives tissue pathology and host mortality. Lethal infection with Ft elicits medullary and extra-medullary myelopoiesis supporting recruitment of large numbers of immature myeloid cells and MDSC to the lungs. These cells fail to mature and die, leading to subsequent necrotic lung damage, loss of pulmonary function, and host death that is partially dependent upon immature Ly6G+ cells. Acceleration of this process may account for the rapid lethality seen with Ft SchuS4. In contrast, during sub-lethal infection with Ft LVS the pulmonary cellular response is characterized by a predominance of mature neutrophils and monocytes required for protection, suggesting a required threshold for lethal bacterial infection. Further, eliciting a mature phagocyte response provides transient, but dramatic, innate protection against Ft SchuS4. This study reveals that the nature of the myeloid cell response may be the primary determinant of host mortality versus survival following Francisella infection.

  14. An Immature Myeloid/Myeloid-Suppressor Cell Response Associated with Necrotizing Inflammation Mediates Lethal Pulmonary Tularemia

    Science.gov (United States)

    Periasamy, Sivakumar; Avram, Dorina; McCabe, Amanda; MacNamara, Katherine C.; Sellati, Timothy J.; Harton, Jonathan A.

    2016-01-01

    Inhalation of Francisella tularensis (Ft) causes acute and fatal pneumonia. The lung cytokine milieu favors exponential Ft replication, but the mechanisms underlying acute pathogenesis and death remain unknown. Evaluation of the sequential and systemic host immune response in pulmonary tularemia reveals that in contrast to overwhelming bacterial burden or cytokine production, an overt innate cellular response to Ft drives tissue pathology and host mortality. Lethal infection with Ft elicits medullary and extra-medullary myelopoiesis supporting recruitment of large numbers of immature myeloid cells and MDSC to the lungs. These cells fail to mature and die, leading to subsequent necrotic lung damage, loss of pulmonary function, and host death that is partially dependent upon immature Ly6G+ cells. Acceleration of this process may account for the rapid lethality seen with Ft SchuS4. In contrast, during sub-lethal infection with Ft LVS the pulmonary cellular response is characterized by a predominance of mature neutrophils and monocytes required for protection, suggesting a required threshold for lethal bacterial infection. Further, eliciting a mature phagocyte response provides transient, but dramatic, innate protection against Ft SchuS4. This study reveals that the nature of the myeloid cell response may be the primary determinant of host mortality versus survival following Francisella infection. PMID:27015566

  15. An Immature Myeloid/Myeloid-Suppressor Cell Response Associated with Necrotizing Inflammation Mediates Lethal Pulmonary Tularemia.

    Directory of Open Access Journals (Sweden)

    Sivakumar Periasamy

    2016-03-01

    Full Text Available Inhalation of Francisella tularensis (Ft causes acute and fatal pneumonia. The lung cytokine milieu favors exponential Ft replication, but the mechanisms underlying acute pathogenesis and death remain unknown. Evaluation of the sequential and systemic host immune response in pulmonary tularemia reveals that in contrast to overwhelming bacterial burden or cytokine production, an overt innate cellular response to Ft drives tissue pathology and host mortality. Lethal infection with Ft elicits medullary and extra-medullary myelopoiesis supporting recruitment of large numbers of immature myeloid cells and MDSC to the lungs. These cells fail to mature and die, leading to subsequent necrotic lung damage, loss of pulmonary function, and host death that is partially dependent upon immature Ly6G+ cells. Acceleration of this process may account for the rapid lethality seen with Ft SchuS4. In contrast, during sub-lethal infection with Ft LVS the pulmonary cellular response is characterized by a predominance of mature neutrophils and monocytes required for protection, suggesting a required threshold for lethal bacterial infection. Further, eliciting a mature phagocyte response provides transient, but dramatic, innate protection against Ft SchuS4. This study reveals that the nature of the myeloid cell response may be the primary determinant of host mortality versus survival following Francisella infection.

  16. Tumor-Induced Myeloid-Derived Suppressor Cells.

    Science.gov (United States)

    De Sanctis, Francesco; Bronte, Vincenzo; Ugel, Stefano

    2016-06-01

    Myeloid-derived suppressor cells (MDSCs) represent a heterogeneous, immune-suppressive leukocyte population that develops systemically and infiltrates tumors. MDSCs can restrain the immune response through different mechanisms including essential metabolite consumption, reactive oxygen and nitrogen species production, as well as display of inhibitory surface molecules that alter T-cell trafficking and viability. Moreover, MDSCs play a role in tumor progression, acting directly on tumor cells and promoting cancer stemness, angiogenesis, stroma deposition, epithelial-to-mesenchymal transition, and metastasis formation. Many biological and pharmaceutical drugs affect MDSC expansion and functions in preclinical tumor models and patients, often reversing host immune dysfunctions and allowing a more effective tumor immunotherapy.

  17. Kinetics of Myeloid-Derived Suppressor Cell Frequency and Function during Simian Immunodeficiency Virus Infection, Combination Antiretroviral Therapy, and Treatment Interruption.

    Science.gov (United States)

    Dross, Sandra E; Munson, Paul V; Kim, Se Eun; Bratt, Debra L; Tunggal, Hillary C; Gervassi, Ana L; Fuller, Deborah H; Horton, Helen

    2017-01-15

    During chronic lentiviral infection, poor clinical outcomes correlate both with systemic inflammation and poor proliferative ability of HIV-specific T cells; however, the connection between the two is not clear. Myeloid-derived suppressor cells (MDSC), which expand during states of elevated circulating inflammatory cytokines, may link the systemic inflammation and poor T cell function characteristic of lentiviral infections. Although MDSC are partially characterized in HIV and SIV infection, questions remain regarding their persistence, activity, and clinical significance. We monitored MDSC frequency and function in SIV-infected rhesus macaques. Low MDSC frequency was observed prior to SIV infection. Post-SIV infection, MDSC were elevated in acute infection and persisted during 7 mo of combination antiretroviral drug therapy (cART). After cART interruption, we observed MDSC expansion of surprising magnitude, the majority being granulocytic MDSC. At all stages of infection, granulocytic MDSC suppressed CD4+ and CD8+ T cell proliferation in response to polyclonal or SIV-specific stimulation. In addition, MDSC frequency correlated significantly with circulating inflammatory cytokines. Acute and post-cART levels of viremia were similar, however, the levels of inflammatory cytokines and MDSC were more pronounced post-cART. Expanded MDSC during SIV infection, especially during the post-cART inflammatory cytokine surge, likely limit cellular responses to infection. As many HIV curative strategies require cART interruption to determine efficacy, our work suggests treatment interruption-induced MDSC may especially undermine the effectiveness of such strategies. MDSC depletion may enhance T cell responses to lentiviral infection and the effectiveness of curative approaches. Copyright © 2017 by The American Association of Immunologists, Inc.

  18. Myeloid-derived suppressor cells are essential for maintaining feto-maternal immunotolerance via STAT3 signaling in mice.

    Science.gov (United States)

    Pan, Ting; Liu, Yufeng; Zhong, Li Mei; Shi, Mao Hua; Duan, Xiao Bing; Wu, Kang; Yang, Qiong; Liu, Chao; Wei, Jian Yang; Ma, Xing Ru; Shi, Kun; Zhang, Hui; Zhou, Jie

    2016-09-01

    Maternal immune system tolerance to the semiallogeneic fetus is essential for a successful pregnancy; however, the mechanisms underlying this immunotolerance have not been fully elucidated. Here, we demonstrate that myeloid-derived suppressor cells play an important role in maintaining feto-maternal tolerance. A significant expansion of granulocytic myeloid-derived suppressor cells was observed in multiple immune organs and decidual tissues from pregnant mice. Pregnancy-derived granulocytic myeloid-derived suppressor cells suppressed T cell responses in a reactive oxygen species-dependent manner and required direct cell-cell contact. Mechanistic studies showed that progesterone facilitated differentiation and activation of granulocytic myeloid-derived suppressor cells, mediated through STAT3 signaling. The STAT3 inhibitor JSI-124 and a specific short hairpin RNA completely abrogated the effects of progesterone on granulocytic myeloid-derived suppressor cells. More importantly, granulocytic myeloid-derived suppressor cell depletion dramatically enhanced the abortion rate in normal pregnant mice, whereas adoptive transfer of granulocytic myeloid-derived suppressor cells clearly reduced the abortion rate in the CBA/J X DBA/2J mouse model of spontaneous abortion. These observations collectively demonstrate that granulocytic myeloid-derived suppressor cells play an essential role in the maintenance of fetal immunotolerance in mice. Furthermore, our study supports the notion that in addition to their well-recognized roles under pathologic conditions, myeloid-derived suppressor cells perform important functions under certain physiologic circumstances. © Society for Leukocyte Biology.

  19. Functional integration of acute myeloid leukemia into the vascular niche.

    Science.gov (United States)

    Cogle, Christopher R; Goldman, Devorah C; Madlambayan, Gerard J; Leon, Ronald P; Masri, Azzah Al; Clark, Hilary A; Asbaghi, Steven A; Tyner, Jeffrey W; Dunlap, Jennifer; Fan, Guang; Kovacsovics, Tibor; Liu, Qiuying; Meacham, Amy; Hamlin, Kimberly L; Hromas, Robert A; Scott, Edward W; Fleming, William H

    2014-10-01

    Vascular endothelial cells are a critical component of the hematopoietic microenvironment that regulates blood cell production. Recent studies suggest the existence of functional cross-talk between hematologic malignancies and vascular endothelium. Here we show that human acute myeloid leukemia (AML) localizes to the vasculature in both patients and in a xenograft model. A significant number of vascular tissue-associated AML cells (V-AML) integrate into vasculature in vivo and can fuse with endothelial cells. V-AML cells acquire several endothelial cell-like characteristics, including the upregulation of CD105, a receptor associated with activated endothelium. Remarkably, endothelial-integrated V-AML shows an almost fourfold reduction in proliferative activity compared with non-vascular-associated AML. Primary AML cells can be induced to downregulate the expression of their hematopoietic markers in vitro and differentiate into phenotypically and functionally defined endothelial-like cells. After transplantation, these leukemia-derived endothelial cells are capable of giving rise to AML. These novel functional interactions between AML cells and normal endothelium along with the reversible endothelial cell potential of AML suggest that vascular endothelium may serve as a previously unrecognized reservoir for AML.

  20. Engagement of SIRP alpha Inhibits Growth and Induces Programmed Cell Death in Acute Myeloid Leukemia Cells

    NARCIS (Netherlands)

    Irandoust, Mahban; Zarate, Julian Alvarez; Hubeek, Isabelle; van Beek, Ellen M.; Schornagel, Karin; Broekhuizen, Aart J. F.; Akyuz, Mercan; van de Loosdrecht, Arjan A.; Delwel, Ruud; Valk, Peter J.; Sonneveld, Edwin; Kearns, Pamela; Creutzig, Ursula; Reinhardt, Dirk; de Bont, Eveline S. J. M.; Coenen, Eva A.; van den Heuvel-Eibrink, Marry M.; Zwaan, C. Michel; Kaspers, Gertjan J. L.; Cloos, Jacqueline; van den Berg, Timo K.

    2013-01-01

    Background: Recent studies show the importance of interactions between CD47 expressed on acute myeloid leukemia (AML) cells and the inhibitory immunoreceptor, signal regulatory protein-alpha (SIRP alpha) on macrophages. Although AML cells express SIRP alpha, its function has not been investigated in

  1. Engagement of SIRPα Inhibits Growth and Induces Programmed Cell Death in Acute Myeloid Leukemia Cells

    NARCIS (Netherlands)

    M. Irandoust (Mahban); J. Alvarez Zarate (Julian); I. Hubeek (I.); E.M. van der Beek (Eline); K. Schornagel (Karin); A.J.F. Broekhuizen (Aart J.); M. Akyuz (Mercan); A.A. van de Loosdrecht (Arjan); H.R. Delwel (Ruud); P.J.M. Valk (Peter); E. Sonneveld (Edwin); P. Kearns (Pamela); U. Creutzig; D. Reinhardt (Dirk); E.S.J.M. de Bont (Eveline); E.A. Coenen (Eva); M.M. van den Heuvel-Eibrink (Marry); C.M. Zwaan (Christian Michel); G.J. Kaspers (Gertjan); J. Cloos (Jacqueline); T.K. van den Berg (Timo)

    2013-01-01

    textabstractBackground: Recent studies show the importance of interactions between CD47 expressed on acute myeloid leukemia (AML) cells and the inhibitory immunoreceptor, signal regulatory protein-alpha (SIRPα) on macrophages. Although AML cells express SIRPα, its function has not been investigated

  2. Malaria parasite infection compromises control of concurrent systemic non-typhoidal Salmonella infection via IL-10-mediated alteration of myeloid cell function.

    Science.gov (United States)

    Lokken, Kristen L; Mooney, Jason P; Butler, Brian P; Xavier, Mariana N; Chau, Jennifer Y; Schaltenberg, Nicola; Begum, Ramie H; Müller, Werner; Luckhart, Shirley; Tsolis, Renée M

    2014-05-01

    Non-typhoidal Salmonella serotypes (NTS) cause a self-limited gastroenteritis in immunocompetent individuals, while children with severe Plasmodium falciparum malaria can develop a life-threatening disseminated infection. This co-infection is a major source of child mortality in sub-Saharan Africa. However, the mechanisms by which malaria contributes to increased risk of NTS bacteremia are incompletely understood. Here, we report that in a mouse co-infection model, malaria parasite infection blunts inflammatory responses to NTS, leading to decreased inflammatory pathology and increased systemic bacterial colonization. Blunting of NTS-induced inflammatory responses required induction of IL-10 by the parasites. In the absence of malaria parasite infection, administration of recombinant IL-10 together with induction of anemia had an additive effect on systemic bacterial colonization. Mice that were conditionally deficient for either myeloid cell IL-10 production or myeloid cell expression of IL-10 receptor were better able to control systemic Salmonella infection, suggesting that phagocytic cells are both producers and targets of malaria parasite-induced IL-10. Thus, IL-10 produced during the immune response to malaria increases susceptibility to disseminated NTS infection by suppressing the ability of myeloid cells, most likely macrophages, to control bacterial infection.

  3. The Influence of Programmed Cell Death in Myeloid Cells on Host Resilience to Infection with Legionella pneumophila or Streptococcus pyogenes

    Science.gov (United States)

    Gamradt, Pia; Xu, Yun; Gratz, Nina; Duncan, Kellyanne; Kobzik, Lester; Högler, Sandra; Decker, Thomas

    2016-01-01

    Pathogen clearance and host resilience/tolerance to infection are both important factors in surviving an infection. Cells of the myeloid lineage play important roles in both of these processes. Neutrophils, monocytes, macrophages, and dendritic cells all have important roles in initiation of the immune response and clearance of bacterial pathogens. If these cells are not properly regulated they can result in excessive inflammation and immunopathology leading to decreased host resilience. Programmed cell death (PCD) is one possible mechanism that myeloid cells may use to prevent excessive inflammation. Myeloid cell subsets play roles in tissue repair, immune response resolution, and maintenance of homeostasis, so excessive PCD may also influence host resilience in this way. In addition, myeloid cell death is one mechanism used to control pathogen replication and dissemination. Many of these functions for PCD have been well defined in vitro, but the role in vivo is less well understood. We created a mouse that constitutively expresses the pro-survival B-cell lymphoma (bcl)-2 protein in myeloid cells (CD68(bcl2tg), thus decreasing PCD specifically in myeloid cells. Using this mouse model we explored the impact that decreased cell death of these cells has on infection with two different bacterial pathogens, Legionella pneumophila and Streptococcus pyogenes. Both of these pathogens target multiple cell death pathways in myeloid cells, and the expression of bcl2 resulted in decreased PCD after infection. We examined both pathogen clearance and host resilience and found that myeloid cell death was crucial for host resilience. Surprisingly, the decreased myeloid PCD had minimal impact on pathogen clearance. These data indicate that the most important role of PCD during infection with these bacteria is to minimize inflammation and increase host resilience, not to aid in the clearance or prevent the spread of the pathogen. PMID:27973535

  4. Targeting the acute myeloid leukemia stem cells.

    Science.gov (United States)

    Krause, Alexandre; Luciana, M; Krause, Fontanari; Rego, Eduardo M

    2010-02-01

    The idea that within the bulk of leukemic cells there are immature progenitors which are intrinsically resistant to chemotherapy and able to repopulate the tumor after treatment is not recent. Nevertheless, the term leukemia stem cells (LSCs) has been adopted recently to describe these immature progenitors based on the fact that they share the most relevant features of the normal hematopoetic stem cells (HSCs), i.e. the self-renewal potential and quiescent status. LSCs differ from their normal counterparts and from the more differentiated leukemic cells regarding the default status of pathways regulating apoptosis, cell cycle, telomere maintenance and transport pumps activity. In addition, unique features regarding the interaction of these cells with the microenvironment have been characterized. Therapeutic strategies targeting these unique features are at different stages of development but the reported results are promising. The aim of this review is, by taking acute myeloid leukemia (AML) as a bona fide example, to discuss some of the mechanisms used by the LSCs to survive and the strategies which could be used to eradicate these cells.

  5. Critical Role of Myeloid-Derived Suppressor Cells in Tumor-Induced Liver Immune Suppression through Inhibition of NKT Cell Function

    Science.gov (United States)

    Zhang, Hongru; Li, Zheng; Wang, Li; Tian, Gaofei; Tian, Jun; Yang, Zishan; Cao, Guangchao; Zhou, Hong; Zhao, Liqing; Wu, Zhenzhou; Yin, Zhinan

    2017-01-01

    Metastasis followed by the tumor development is the primary cause of death for cancer patients. However, the underlying molecular mechanisms of how the growth of tumor resulted in the immune suppression, especially at the blood-enriched organ such as liver, were largely unknown. In this report, we studied the liver immune response of tumor-bearing (TB) mice using concanavalin A (Con A)-induced hepatitis model. We demonstrated that TB mice displayed an immune suppression phenotype, with attenuated alanine aminotransferase levels and liver damage upon Con A treatment. We also elucidated that large amounts of myeloid-derived suppressor cells (MDSCs) being influx into the liver in TB mice and these MDSCs were essential for liver immune suppression through both depletion and reconstitution approaches. We further determined that these MDSCs selectively suppressed the IFN-γ production deriving from NKT cells through membrane-bound transforming growth factor β (TGF-β). Finally, we defined a tumor-derived TGF-β-triggered CXCL1/2/5- and CXCR2-dependent recruitment of MDSC into the liver. In summary, our results defined a novel mechanism of liver immune suppression triggered by growing living tumor and provided possible therapeutic targets against these MDSCs.

  6. Hematopoietic stem cells express multiple myeloid markers: implications for the origin and targeted therapy of acute myeloid leukemia

    OpenAIRE

    Taussig, David C.; Pearce, Daniel J; Simpson, Catherine; Rohatiner, Ama Z; Lister, T. Andrew; Kelly, Gavin; Luongo, Jennifer L.; Danet-Desnoyers, Gwenn-aël H.; Bonnet, Dominique

    2005-01-01

    Human hematopoietic stem cells (HSCs) are generally regarded as being devoid of the markers expressed by differentiated blood cells, the lineage-specific antigens. However, recent work suggests that genes associated with the myeloid lineage are transcribed in mouse HSCs. Here, we explore whether myeloid genes are actually translated in human HSCs. We show that CD33, CD13, and CD123, well-established myeloid markers, are expressed on human long-term repopulating cells from cord blood and bone ...

  7. Metabolic regulation of suppressive myeloid cells in cancer.

    Science.gov (United States)

    Sica, Antonio; Strauss, Laura; Consonni, Francesca Maria; Travelli, Cristina; Genazzani, Armando; Porta, Chiara

    2017-06-01

    Cancer cells rewire their metabolism to promote growth, survival, proliferation and long-term maintenance. The common feature of this altered metabolism is the increased glucose uptake and fermentation of glucose to lactate, which is observed even in the presence of completely functioning mitochondria. This effect is known as the 'Warburg Effect' and its intensive investigation in the last decade has partially established either its causes or its functions. It is now emerging that a major side effect of the Warburg Effect is immunosuppression, which limits the immunogenicity of cancer cells and therefore restricts the therapeutic efficacy of anticancer immunotherapy. Here we discuss how the metabolic communication between cancer and infiltrating myeloid cells contributes to cancer immune evasion and how the understanding of these mechanisms may improve current immunotherapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Increased levels of circulating and tumor-infiltrating granulocytic myeloid cells in colorectal cancer patients

    Directory of Open Access Journals (Sweden)

    Salman M Toor

    2016-12-01

    Full Text Available Increased levels of myeloid cells, especially myeloid-derived suppressor cells (MDSCs, have been reported to correlate with bad prognosis and reduced survival in cancer patients. However, limited data are available on their conclusive phenotypes and their correlation with clinical settings. The aim of this study was to investigate levels and phenotype of myeloid cells in peripheral blood and tumor microenvironment of colorectal cancer (CRC patients, compared to blood from healthy donors (HDs and paired, adjacent non-tumor colon tissue. Flow cytometric analysis was performed to examine the expression of different myeloid markers in fresh peripheral blood samples from CRC patients and HDs, and tissue-infiltrating immune cells from CRC patients. We found significantly higher levels of cells expressing myeloid markers and lacking the expression of MHC class II molecule HLA-DR in blood and tumor of CRC patients. Further analysis revealed that these cells were granulocytic and expressed Arginase 1 (ARG1, indicative of their suppressive phenotype. These expanded cells could be neutrophils or granulocytic MDSCs, and we refer to them as granulocytic myeloid cells (GMCs due to the phenotypical and functional overlap between these cell subsets. Interestingly, the expansion of peripheral GMCs correlated with higher stage and histological grade of cancer, thereby suggesting their role in cancer progression. Furthermore, an increase in CD33+CD11b+HLA-DR-CD14-CD15- immature myeloid cells (IMCs was also observed in CRC tumor tissue. Our work shows that GMCs are expanded in circulation and tumor microenvironment of CRC patients, which provides further insights for developing immunotherapeutic approaches targeting these cell subsets to enhance anti-tumor immune and clinical responses.

  9. On the armament and appearances of human myeloid-derived suppressor cells.

    Science.gov (United States)

    Poschke, Isabel; Kiessling, Rolf

    2012-09-01

    Myeloid-derived suppressor cells (MDSC) have frequently been observed in patients with cancer. This heterogeneous population of myeloid cells can exert potent suppression of lymphocyte function and thereby poses a significant hurdle to natural or therapeutically induced anti-tumor immunity. On the other hand, the natural function of MDSC is not yet well understood and their role in infection, inflammation and autoimmune disease is still puzzling. Understanding MDSC biology will provide the tools necessary for therapeutic targeting of this population, but also permit exploitation of their strong tolerogenic function in the treatment of inflammatory conditions and the prevention of graft rejection.

  10. Therapeutic targeting of myeloid-derived suppressor cells.

    Science.gov (United States)

    Ugel, Stefano; Delpozzo, Federica; Desantis, Giacomo; Papalini, Francesca; Simonato, Francesca; Sonda, Nada; Zilio, Serena; Bronte, Vincenzo

    2009-08-01

    Myeloid-derived suppressor cells (MDSCs) represent a subset of myeloid cells that expand under pathological conditions, such as cancer development, acute and chronic infections, trauma, bone marrow transplantations, and some autoimmune diseases. MDSCs mediate a negative regulation of the immune response by affecting different T lymphocyte subsets. Potential mechanisms, which underlie this inhibitory activity range from those requiring direct cell-to-cell contact with others, more indirect, and mediated by the modification of the microenvironment. Pharmacological inhibition of MDSC suppressive pathways is a promising strategy to overcome disease-induced immune defects, which might be a key step in enhancing the effectiveness of immune-based therapies.

  11. Lysosomal disruption preferentially targets acute myeloid leukemia cells and progenitors

    Science.gov (United States)

    Sukhai, Mahadeo A.; Prabha, Swayam; Hurren, Rose; Rutledge, Angela C.; Lee, Anna Y.; Sriskanthadevan, Shrivani; Sun, Hong; Wang, Xiaoming; Skrtic, Marko; Seneviratne, Ayesh; Cusimano, Maria; Jhas, Bozhena; Gronda, Marcela; MacLean, Neil; Cho, Eunice E.; Spagnuolo, Paul A.; Sharmeen, Sumaiya; Gebbia, Marinella; Urbanus, Malene; Eppert, Kolja; Dissanayake, Dilan; Jonet, Alexia; Dassonville-Klimpt, Alexandra; Li, Xiaoming; Datti, Alessandro; Ohashi, Pamela S.; Wrana, Jeff; Rogers, Ian; Sonnet, Pascal; Ellis, William Y.; Corey, Seth J.; Eaves, Connie; Minden, Mark D.; Wang, Jean C.Y.; Dick, John E.; Nislow, Corey; Giaever, Guri; Schimmer, Aaron D.

    2012-01-01

    Despite efforts to understand and treat acute myeloid leukemia (AML), there remains a need for more comprehensive therapies to prevent AML-associated relapses. To identify new therapeutic strategies for AML, we screened a library of on- and off-patent drugs and identified the antimalarial agent mefloquine as a compound that selectively kills AML cells and AML stem cells in a panel of leukemia cell lines and in mice. Using a yeast genome-wide functional screen for mefloquine sensitizers, we identified genes associated with the yeast vacuole, the homolog of the mammalian lysosome. Consistent with this, we determined that mefloquine disrupts lysosomes, directly permeabilizes the lysosome membrane, and releases cathepsins into the cytosol. Knockdown of the lysosomal membrane proteins LAMP1 and LAMP2 resulted in decreased cell viability, as did treatment of AML cells with known lysosome disrupters. Highlighting a potential therapeutic rationale for this strategy, leukemic cells had significantly larger lysosomes compared with normal cells, and leukemia-initiating cells overexpressed lysosomal biogenesis genes. These results demonstrate that lysosomal disruption preferentially targets AML cells and AML progenitor cells, providing a rationale for testing lysosomal disruption as a novel therapeutic strategy for AML. PMID:23202731

  12. The rate of spontaneous mutations in human myeloid cells

    Energy Technology Data Exchange (ETDEWEB)

    Araten, David J., E-mail: david.araten@nyumc.org [Division of Hematology, Department of Veterans Affairs New York Harbor Healthcare System (United States); Division of Hematology, Department of Medicine, NYU School of Medicine and the NYU Langone Cancer Center (United States); Krejci, Ondrej [Division of Experimental Hematology and Cancer Biology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States); DiTata, Kimberly [Division of Hematology, Department of Medicine, NYU School of Medicine and the NYU Langone Cancer Center (United States); Wunderlich, Mark [Division of Experimental Hematology and Cancer Biology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States); Sanders, Katie J.; Zamechek, Leah [Division of Hematology, Department of Medicine, NYU School of Medicine and the NYU Langone Cancer Center (United States); Mulloy, James C. [Division of Experimental Hematology and Cancer Biology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States)

    2013-09-15

    Highlights: • We provide the first measurement of the mutation rate (μ) in human myeloid cells. • μ is measured to be 3.6–23 × 10{sup −7} per cell division. • The AML-ETO and MLL-AF9 fusions do not seem to increase μ. • Cooperating mutations in NRAS, FLT3 and p53 not seem to increase μ. • Hypermutability may be required to explain leukemogenesis. - Abstract: The mutation rate (μ) is likely to be a key parameter in leukemogenesis, but historically, it has been difficult to measure in humans. The PIG-A gene has some advantages for the detection of spontaneous mutations because it is X-linked, and therefore only one mutation is required to disrupt its function. Furthermore, the PIG-A-null phenotype is readily detected by flow cytometry. Using PIG-A, we have now provided the first in vitro measurement of μ in myeloid cells, using cultures of CD34+ cells that are transduced with either the AML-ETO or the MLL-AF9 fusion genes and expanded with cytokines. For the AML-ETO cultures, the median μ value was ∼9.4 × 10{sup −7} (range ∼3.6–23 × 10{sup −7}) per cell division. In contrast, few spontaneous mutations were observed in the MLL-AF9 cultures. Knockdown of p53 or introduction of mutant NRAS or FLT3 alleles did not have much of an effect on μ. Based on these data, we provide a model to predict whether hypermutability must occur in the process of leukemogenesis.

  13. Interleukin-4 enhances trafficking and functional activities of GM-CSF-stimulated mouse myeloid-derived dendritic cells at late differentiation stage

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Shu-Yi, E-mail: in_shuyi@hotmail.com [Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, ROC (China); Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan, ROC (China); Taiwan International Graduate Program (TIGP), Molecular and Biological Agricultural Sciences Program, Academia Sinica, Taipei, Taiwan, ROC (China); Wang, Chien-Yu, E-mail: sallywang1973@hotmail.com [Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, ROC (China); Yang, Ning-Sun, E-mail: nsyang@gate.sinica.edu.tw [Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, ROC (China); Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan, ROC (China); Taiwan International Graduate Program (TIGP), Molecular and Biological Agricultural Sciences Program, Academia Sinica, Taipei, Taiwan, ROC (China)

    2011-09-10

    Mouse bone marrow-derived dendritic cells (BMDCs) are being employed as an important model for translational research into the development of DC-based therapeutics. For such use, the localization and specialized mobility of injected BMDCs within specific immune tissues are known to define their immunity and usefulness in vivo. In this study, we demonstrate that IL-4, a key driving factor for in vitro propagation and differentiation of BMDCs, when added during a late culture stage can enhance the in vivo trafficking activity of granulocyte-macrophage colony-stimulating factor (GM-CSF)-induced BMDCs. It suggests that the temporal control of IL-4 stimulation during the in vitro generation of DCs drastically affects the DC trafficking efficiency in vivo. With this modification of IL-4 stimulation, we also show that much less cytokine was needed to generate BMDCs with high purity and yield that secrete a high level of cytokines and possess a good capacity to induce proliferation of allogeneic CD4{sup +}T cells, as compared to the conventional method that uses a continuous supplement of GM-CSF and IL-4 throughout cultivation. These results provide us with an important know-how for differentiation of BMDCs from myeloid stem cells, and for use of other immune cells in related medical or stem cell applications.

  14. Extramedullary Myeloid Cell Tumour Presenting As Leukaemia Cutis

    Directory of Open Access Journals (Sweden)

    Thappa Devinder Mohan

    2002-01-01

    Full Text Available We herewith report a case of extramedullary myeloid cell tumour presenting as leukaemia cutis for its rarity. It occurred in a 50 year old male patient who presented to us with a 40 days history of painless raised solid skin swellings over the trunk. Histopathological examination of the skin biopsy and bone marrow biopsy showed features suggestive of non-Hodgkin’s lymphoma. Immunophenotyping on skin biopsy specimens and bone marrow biopsy found tumour cells expressing CD43 and Tdt but were negative for CD3 and CD20. These features were consistent with extramedullary myeloid cell tumour involving skin and subcutis (cutaneous manifestation of acute myeloid leukaemia.

  15. Therapeutic Effects of Myeloid Cell Leukemia-1 siRNA on Human Acute Myeloid Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Hadi Karami

    2014-05-01

    Full Text Available Purpose: Up-regulation of Mcl-1, a known anti-apoptotic protein, is associated with the survival and progression of various malignancies including leukemia. The aim of this study was to explore the effect of Mcl-1 small interference RNA (siRNA on the proliferation and apoptosis of HL-60 acute myeloid leukemia (AML cells. Methods: siRNA transfection was performed using Lipofectamine™2000 reagent. Relative mRNA and protein expressions were quantified by quantitative real-time PCR and Western blotting, respectively. Trypan blue assay was performed to assess tumor cell proliferation after siRNA transfection. The cytotoxic effect of Mcl-1 siRNA on leukemic cells was measured using MTT assay. Apoptosis was detected using ELISA cell death assay. Results: Mcl-1 siRNA clearly lowered both Mcl-1 mRNA and protein levels in a time-dependent manner, leading to marked inhibition of cell survival and proliferation. Furthermore, Mcl-1 down-regulation significantly enhanced the extent of HL-60 apoptotic cells. Conclusion: Our results suggest that the down-regulation of Mcl-1 by siRNA can effectively trigger apoptosis and inhibit the proliferation of leukemic cells. Therefore, Mcl-1 siRNA may be a potent adjuvant in AML therapy.

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  7. Tumor-derived lactate and myeloid-derived suppressor cells: Linking metabolism to cancer immunology.

    Science.gov (United States)

    Husain, Zaheed; Seth, Pankaj; Sukhatme, Vikas P

    2013-11-01

    Many malignant cells produce increased amounts of lactate, which promotes the development of myeloid-derived suppressor cells (MDSCs). MDSCs, lactate, and a low pH in the tumor microenvironment inhibit the function of natural killer (NK) cells and T lymphocytes, hence allowing for disease progression. Ketogenic diets can deplete tumor-bearing animals from MDSCs and regulatory T cells, thereby improving their immunological profile.

  8. CatacLysMic specificity when targeting myeloid cells?

    Science.gov (United States)

    Blank, Thomas; Prinz, Marco

    2016-06-01

    The antibacterial enzyme lysozyme M (LysM) encoded by the Lyz2 gene is broadly expressed in myeloblasts, macrophages, and neutrophils, and thus has been used for a long time as a cell-specific marker for myeloid cells in mice. In order to delete loxP-site flanked genes in myeloid cells, a Cre-recombinase (Cre) expressing mouse line was created by inserting Cre-coding sequence into the translational start site of the LysM gene. In this issue of the European Journal of Immunology [2016. 46: 1529-1532], Orthgiess et al. verify, with the help of tdTomato and YFP reporter mouse lines, LysM-driven recombination. Unexpectedly, the authors also describe major expression of the tdTomato reporter protein in brain neurons of the central nervous system (CNS), with only a very small percentage of gene recombination in myeloid cells of the brain, called microglia. These findings cause justified concerns regarding the efficient and specific targeting of microglia and peripheral myeloid cells using LysM-Cre mice and should stimulate thoughts on conclusions drawn from past experiments on the diseased CNS employing this Cre/loxP-deleter line. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. MicroRNA-150 Expression Induces Myeloid Differentiation of Human Acute Leukemia Cells and Normal Hematopoietic Progenitors

    Science.gov (United States)

    Morris, Valerie A.; Zhang, Ailin; Yang, Taimei; Stirewalt, Derek L.; Ramamurthy, Ranjani; Meshinchi, Soheil; Oehler, Vivian G.

    2013-01-01

    In acute myeloid leukemia (AML) and blast crisis (BC) chronic myeloid leukemia (CML) normal differentiation is impaired. Differentiation of immature stem/progenitor cells is critical for normal blood cell function. MicroRNAs (miRNAs or miRs) are small non-coding RNAs that interfere with gene expression by degrading messenger RNAs (mRNAs) or blocking protein translation. Aberrant miRNA expression is a feature of leukemia and miRNAs also play a significant role in normal hematopoiesis and differentiation. We have identified miRNAs differentially expressed in AML and BC CML and identified a new role for miR-150 in myeloid differentiation. Expression of miR-150 is low or absent in BC CML and AML patient samples and cell lines. We have found that expression of miR-150 in AML cell lines, CD34+ progenitor cells from healthy individuals, and primary BC CML and AML patient samples at levels similar to miR-150 expression in normal bone marrow promotes myeloid differentiation of these cells. MYB is a direct target of miR-150, and we have identified that the observed phenotype is partially mediated by MYB. In AML cell lines, differentiation of miR-150 expressing cells occurs independently of retinoic acid receptor α (RARA) signaling. High-throughput gene expression profiling (GEP) studies of the AML cell lines HL60, PL21, and THP-1 suggest that activation of CEPBA, CEBPE, and cytokines associated with myeloid differentiation in miR-150 expressing cells as compared to control cells contributes to myeloid differentiation. These data suggest that miR-150 promotes myeloid differentiation, a previously uncharacterized role for this miRNA, and that absent or low miR-150 expression contributes to blocked myeloid differentiation in acute leukemia cells. PMID:24086639

  10. MicroRNA-150 expression induces myeloid differentiation of human acute leukemia cells and normal hematopoietic progenitors.

    Directory of Open Access Journals (Sweden)

    Valerie A Morris

    Full Text Available In acute myeloid leukemia (AML and blast crisis (BC chronic myeloid leukemia (CML normal differentiation is impaired. Differentiation of immature stem/progenitor cells is critical for normal blood cell function. MicroRNAs (miRNAs or miRs are small non-coding RNAs that interfere with gene expression by degrading messenger RNAs (mRNAs or blocking protein translation. Aberrant miRNA expression is a feature of leukemia and miRNAs also play a significant role in normal hematopoiesis and differentiation. We have identified miRNAs differentially expressed in AML and BC CML and identified a new role for miR-150 in myeloid differentiation. Expression of miR-150 is low or absent in BC CML and AML patient samples and cell lines. We have found that expression of miR-150 in AML cell lines, CD34+ progenitor cells from healthy individuals, and primary BC CML and AML patient samples at levels similar to miR-150 expression in normal bone marrow promotes myeloid differentiation of these cells. MYB is a direct target of miR-150, and we have identified that the observed phenotype is partially mediated by MYB. In AML cell lines, differentiation of miR-150 expressing cells occurs independently of retinoic acid receptor α (RARA signaling. High-throughput gene expression profiling (GEP studies of the AML cell lines HL60, PL21, and THP-1 suggest that activation of CEPBA, CEBPE, and cytokines associated with myeloid differentiation in miR-150 expressing cells as compared to control cells contributes to myeloid differentiation. These data suggest that miR-150 promotes myeloid differentiation, a previously uncharacterized role for this miRNA, and that absent or low miR-150 expression contributes to blocked myeloid differentiation in acute leukemia cells.

  11. Expression of the B-cell receptor component CD79a on immature myeloid cells contributes to their tumor promoting effects.

    Directory of Open Access Journals (Sweden)

    Dror Luger

    Full Text Available The role of myeloid derived suppressor cells (MDSCs in promoting tumorigenesis is well-established, and significant effort is being made to further characterize surface markers on MDSCs both for better diagnosis and as potential targets for therapy. Here we show that the B cell receptor adaptor molecule CD79a is unexpectedly expressed on immature bone marrow myeloid cells, and is upregulated on MDSCs generated in multiple different mouse models of metastatic but not non-metastatic cancer. CD79a on MDSCs is upregulated and activated in response to soluble factors secreted by tumor cells. Activation of CD79a on mouse MDSCs, by crosslinking with a specific antibody, maintained their immature phenotype (CD11b+Gr1+, enhanced their migration, increased their suppressive effect on T cell proliferation, and increased secretion of pro-tumorigenic cytokines such as IL-6 and CCL22. Furthermore, crosslinking CD79a on myeloid cells activated signaling through Syk, BLNK, ERK and STAT3 phosphorylation. In vivo, CD79+ myeloid cells showed enhanced ability to promote primary tumor growth and metastasis. Finally we demonstrate that CD79a is upregulated on circulating myeloid cells from lung cancer patients, and that CD79a+ myeloid cells infiltrate human breast tumors. We propose that CD79a plays a functional role in the tumor promoting effects of myeloid cells, and may represent a novel target for cancer therapy.

  12. Testing the Role of Myeloid Cell Glucose Flux in Inflammation and Atherosclerosis

    Directory of Open Access Journals (Sweden)

    Tomohiro Nishizawa

    2014-04-01

    Full Text Available Inflammatory activation of myeloid cells is accompanied by increased glycolysis, which is required for the surge in cytokine production. Although in vitro studies suggest that increased macrophage glucose metabolism is sufficient for cytokine induction, the proinflammatory effects of increased myeloid cell glucose flux in vivo and the impact on atherosclerosis, a major complication of diabetes, are unknown. We therefore tested the hypothesis that increased glucose uptake in myeloid cells stimulates cytokine production and atherosclerosis. Overexpression of the glucose transporter GLUT1 in myeloid cells caused increased glycolysis and flux through the pentose phosphate pathway but did not induce cytokines. Moreover, myeloid-cell-specific overexpression of GLUT1 in LDL receptor-deficient mice was ineffective in promoting atherosclerosis. Thus, increased glucose flux is insufficient for inflammatory myeloid cell activation and atherogenesis. If glucose promotes atherosclerosis by increasing cellular glucose flux, myeloid cells do not appear to be the key targets.

  13. Alloreactive natural killer cells for the treatment of acute myeloid leukemia: from stem cell transplantation to adoptive immunotherapy

    Directory of Open Access Journals (Sweden)

    Loredana eRuggeri

    2015-10-01

    Full Text Available Natural killer cells express activating and inhibitory receptors which recognize MHC class I alleles, termed Killer cell Immunoglobulin-like Receptors (KIRs. Preclinical and clinical data from haploidentical T-cell depleted stem cell transplantation have demonstrated that alloreactive KIR-L mismatched natural killer cells play a major role as effectors against acute myeloid leukemia. Outside the transplantation setting, several reports have proven the safety and feasibility of natural killer cell infusion in acute myeloid leukemia patients and, in some cases, provided evidence that transferred NK cells are functionally alloreactive and may have a role in disease control. Aim of the present work is to briefly summarize the most recent advances in the field by moving from the first preclinical and clinical demonstration of donor NK alloreactivity in the transplantation setting to the most recent attempts of exploiting the use of alloreactive NK cell infusion as a means of adoptive immunotherapy against acute myeloid leukemia. Altogether, these data highlight the pivotal role of NK cells for the development of novel immunological approaches in the clinical management of acute myeloid leukemia.

  14. Synchronous Occurrence of Chronic Myeloid Leukemia and Mantle Cell Lymphoma

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    Prajwol Pathak

    2017-01-01

    Full Text Available Chronic myeloid leukemia (CML and mantle cell lymphoma (MCL are hematologic malignancies that originate from different oligopotent progenitor stem cells, namely, common myeloid and lymphoid progenitor cells, respectively. Although blastic transformation of CML can occur in the lymphoid lineage and CML has been related to non-Hodgkin lymphoma on transformation, to our knowledge, de novo and synchronous occurrence of CML and MCL has not been reported. Herein, we report the first case of synchronous CML and MCL in an otherwise healthy 38-year-old man. Potential etiologies and pathological relationships between the two malignancies are explored, including the possibility that the downstream effects of BCR-ABL may link it to an overexpression of cyclin D1, which is inherent to the etiology of MCL.

  15. Myeloid leukemic progenitor cells can be specifically targeted by minor histocompatibility antigen LRH-1-reactive cytotoxic T cells.

    Science.gov (United States)

    Norde, Wieger J; Overes, Ingrid M; Maas, Frans; Fredrix, Hanny; Vos, Johanna C M; Kester, Michel G D; van der Voort, Robbert; Jedema, Inge; Falkenburg, J H Frederik; Schattenberg, Anton V; de Witte, Theo M; Dolstra, Harry

    2009-03-05

    CD8(+) T cells recognizing minor histocompatibility antigens (MiHAs) on leukemic stem and progenitor cells play a pivotal role in effective graft-versus-leukemia reactivity after allogeneic stem cell transplantation (SCT). Previously, we identified a hematopoiesis-restricted MiHA, designated LRH-1, which is presented by HLA-B7 and encoded by the P2X5 purinergic receptor gene. We found that P2X5 is significantly expressed in CD34(+) leukemic subpopulations from chronic myeloid leukemia (CML) and acute myeloid leukemia (AML) patients. Here, we demonstrate that LRH-1-specific CD8(+) T-cell responses are frequently induced in myeloid leukemia patients following donor lymphocyte infusions. Patients with high percentages of circulating LRH-1-specific CD8(+) T cells had no or only mild graft-versus-host disease. Functional analysis showed that LRH-1-specific cytotoxic T lymphocytes (CTLs) isolated from 2 different patients efficiently target LRH-1-positive leukemic CD34(+) progenitor cells from both CML and AML patients, whereas mature CML cells are only marginally lysed due to down-regulation of P2X5. Furthermore, we observed that relative resistance to LRH-1 CTL-mediated cell death due to elevated levels of antiapoptotic XIAP could be overcome by IFN-gamma prestimulation and increased CTL-target ratios. These findings provide a rationale for use of LRH-1 as immunotherapeutic target antigen to treat residual or persisting myeloid malignancies after allogeneic SCT.

  16. MiRNA182 regulates percentage of myeloid and erythroid cells in chronic myeloid leukemia.

    Science.gov (United States)

    Arya, Deepak; Sachithanandan, Sasikala P; Ross, Cecil; Palakodeti, Dasaradhi; Li, Shang; Krishna, Sudhir

    2017-01-12

    The deregulation of lineage control programs is often associated with the progression of haematological malignancies. The molecular regulators of lineage choices in the context of tyrosine kinase inhibitor (TKI) resistance remain poorly understood in chronic myeloid leukemia (CML). To find a potential molecular regulator contributing to lineage distribution and TKI resistance, we undertook an RNA-sequencing approach for identifying microRNAs (miRNAs). Following an unbiased screen, elevated miRNA182-5p levels were detected in Bcr-Abl-inhibited K562 cells (CML blast crisis cell line) and in a panel of CML patients. Earlier, miRNA182-5p upregulation was reported in several solid tumours and haematological malignancies. We undertook a strategy involving transient modulation and CRISPR/Cas9 (clustered regularly interspersed short palindromic repeats)-mediated knockout of the MIR182 locus in CML cells. The lineage contribution was assessed by methylcellulose colony formation assay. The transient modulation of miRNA182-5p revealed a biased phenotype. Strikingly, Δ182 cells (homozygous deletion of MIR182 locus) produced a marked shift in lineage distribution. The phenotype was rescued by ectopic expression of miRNA182-5p in Δ182 cells. A bioinformatic analysis and Hes1 modulation data suggested that Hes1 could be a putative target of miRNA182-5p. A reciprocal relationship between miRNA182-5p and Hes1 was seen in the context of TK inhibition. In conclusion, we reveal a key role for miRNA182-5p in restricting the myeloid development of leukemic cells. We propose that the Δ182 cell line will be valuable in designing experiments for next-generation pharmacological interventions.

  17. Technical Advance: Transcription factor, promoter, and enhancer utilization in human myeloid cells

    Science.gov (United States)

    Joshi, Anagha; Pooley, Christopher; Freeman, Tom C.; Lennartsson, Andreas; Babina, Magda; Schmidl, Christian; Geijtenbeek, Teunis; Michoel, Tom; Severin, Jessica; Itoh, Masayoshi; Lassmann, Timo; Kawaji, Hideya; Hayashizaki, Yoshihide; Carninci, Piero; Forrest, Alistair R. R.; Rehli, Michael; Hume, David A.

    2015-01-01

    The generation of myeloid cells from their progenitors is regulated at the level of transcription by combinatorial control of key transcription factors influencing cell-fate choice. To unravel the global dynamics of this process at the transcript level, we generated transcription profiles for 91 human cell types of myeloid origin by use of CAGE profiling. The CAGE sequencing of these samples has allowed us to investigate diverse aspects of transcription control during myelopoiesis, such as identification of novel transcription factors, miRNAs, and noncoding RNAs specific to the myeloid lineage. We further reconstructed a transcription regulatory network by clustering coexpressed transcripts and associating them with enriched cis-regulatory motifs. With the use of the bidirectional expression as a proxy for enhancers, we predicted over 2000 novel enhancers, including an enhancer 38 kb downstream of IRF8 and an intronic enhancer in the KIT gene locus. Finally, we highlighted relevance of these data to dissect transcription dynamics during progressive maturation of granulocyte precursors. A multifaceted analysis of the myeloid transcriptome is made available (www.myeloidome.roslin.ed.ac.uk). This high-quality dataset provides a powerful resource to study transcriptional regulation during myelopoiesis and to infer the likely functions of unannotated genes in human innate immunity. PMID:25717144

  18. Technical Advance: Transcription factor, promoter, and enhancer utilization in human myeloid cells.

    Science.gov (United States)

    Joshi, Anagha; Pooley, Christopher; Freeman, Tom C; Lennartsson, Andreas; Babina, Magda; Schmidl, Christian; Geijtenbeek, Teunis; Michoel, Tom; Severin, Jessica; Itoh, Masayoshi; Lassmann, Timo; Kawaji, Hideya; Hayashizaki, Yoshihide; Carninci, Piero; Forrest, Alistair R R; Rehli, Michael; Hume, David A

    2015-05-01

    The generation of myeloid cells from their progenitors is regulated at the level of transcription by combinatorial control of key transcription factors influencing cell-fate choice. To unravel the global dynamics of this process at the transcript level, we generated transcription profiles for 91 human cell types of myeloid origin by use of CAGE profiling. The CAGE sequencing of these samples has allowed us to investigate diverse aspects of transcription control during myelopoiesis, such as identification of novel transcription factors, miRNAs, and noncoding RNAs specific to the myeloid lineage. We further reconstructed a transcription regulatory network by clustering coexpressed transcripts and associating them with enriched cis-regulatory motifs. With the use of the bidirectional expression as a proxy for enhancers, we predicted over 2000 novel enhancers, including an enhancer 38 kb downstream of IRF8 and an intronic enhancer in the KIT gene locus. Finally, we highlighted relevance of these data to dissect transcription dynamics during progressive maturation of granulocyte precursors. A multifaceted analysis of the myeloid transcriptome is made available (www.myeloidome.roslin.ed.ac.uk). This high-quality dataset provides a powerful resource to study transcriptional regulation during myelopoiesis and to infer the likely functions of unannotated genes in human innate immunity.

  19. Primary cerebellar extramedullary myeloid cell tumor mimicking oligodendroglioma.

    Science.gov (United States)

    Ho, D M; Wong, T T; Guo, W Y; Chang, K P; Yen, S H

    1997-10-01

    Extramedullary myeloid cell tumors (EMCTs) are tumors consisting of immature cells of the myeloid series that occur outside the bone marrow. Most of them are associated with acute myelogenous leukemia or other myeloproliferative disorders, and a small number occur as primary lesions, i.e., are not associated with hematological disorders. Occurrence inside the cranium is rare, and there has been only one case of primary EMCT involving the cerebellum reported in the literature. The case we report here is a blastic EMCT occurring in the cerebellum of a 3-year-old boy who had no signs of leukemia or any hematological disorder throughout the entire course. The cerebellar tumor was at first misdiagnosed as an "oligodendroglioma" because of the uniformity and "fried egg" artifact of the tumor cells. The tumor disappeared during chemotherapy consisting of 12 treatments. However, it recurred and metastasized to the cerebrospinal fluid (CSF) shortly after the therapy was completed. A diagnosis of EMCT was suspected because of the presence of immature myeloid cells in the CSF, and was confirmed by anti-myeloperoxidase and anti-lysozyme immunoreactivity of the cerebellar tumor. The patient succumbed 1 year and 3 months after the first presentation of the disease.

  20. Acute myeloid dendritic cell leukaemia with specific cutaneous involvement: a diagnostic challenge.

    Science.gov (United States)

    Ferran, M; Gallardo, F; Ferrer, A M; Salar, A; Pérez-Vila, E; Juanpere, N; Salgado, R; Espinet, B; Orfao, A; Florensa, L; Pujol, R M

    2008-05-01

    Myeloid or type 1 dendritic cell leukaemia is an exceedingly rare haematopoietic neoplasm characterized by a specific immunophenotypic profile close to plasmacytoid dendritic cell and acute myelogenous leukaemia. A 77-year-old man presenting specific cutaneous infiltration by myeloid dendritic cell leukaemia is reported. The clinical features as well as the cutaneous histopathological and immunohistochemical features led to the initial diagnosis of CD4+/CD56+ haematodermic neoplasm. However, extensive immunophenotypic studies performed from peripheral blood blasts disclosed that leukaemic cells expressed myeloid dendritic cell markers, confirming the diagnosis. The diagnostic difficulties of specific cutaneous involvement by myeloid dendritic cell leukaemia on the basis of routine histopathological and immunohistochemical features are highlighted.

  1. Myeloid derived suppressor cells and their role in tolerance induction in cancer.

    Science.gov (United States)

    Fujimura, Taku; Mahnke, Karsten; Enk, Alexander H

    2010-07-01

    Myeloid derived suppressor cells (MDSCs) comprise a phenotypically heterogeneous population of cells, which can be found in tumor-bearing mice and in patients with cancer. MDSCs play a central role in the induction of peripheral tolerance. Together with regulatory T cells (Tregs) they promote an immunosuppressive environment in tumor-bearing hosts. The phenotype of MDSCs differs in humans and mice, and the exact mechanisms of their suppressive function are still controversially discussed. In summary, MDSCs are a group of phenotypically heterogeneous cells of myeloid origin that have common biological activities. In this review, we discuss the definition of MDSCs, the proposed mechanisms of expansion and the recruitment and activation of MDSCs, as well as their biological activities in tumorbearing hosts to assess the potential therapeutic applications.

  2. Allogeneic stem cell transplantation in acute myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Natasha Ali

    2012-11-01

    Full Text Available We report a case series of 12 patients with acute myeloid leukemia who underwent allogeneic stem cell transplant with a matched related donor. Male to female ratio was 1:1. The main complication post-transplant was graft-versus-host disease (n=7 patients. Transplant-related mortality involved one patient; cause of death was multi-organ failure. After a median follow up of 36.0±11.3 months, overall survival was 16%.

  3. Elevated frequencies of leukemic myeloid and plasmacytoid dendritic cells in acute myeloid leukemia with the FLT3 internal tandem duplication

    OpenAIRE

    Rickmann, Mareike; Krauter, Juergen; Stamer, Kathrin; Heuser, Michael; Salguero, Gustavo; Mischak-Weissinger, Eva; Ganser, Arnold; Stripecke, Renata

    2011-01-01

    Abstract Some 30% of acute myeloid leukemia (AML) patients display an internal tandem duplication (ITD) mutation in the FMS-like tyrosine kinase 3 (FLT3) gene. FLT3-ITDs are known to drive hematopoietic stem cells towards FLT3 ligand independent growth, but the effects on dendritic cell (DC) differentiation during leukemogenesis are not clear. We compared the frequency of cells with immunophenotype of myeloid DC (mDC: Lin?, HLA-DR+, CD11c+, CD86+) and plasmacytoid DC (pDC: Lin?, HL...

  4. Increase in myeloid-derived suppressor cells (MDSCs) associated with minimal residual disease (MRD) detection in adult acute myeloid leukemia.

    Science.gov (United States)

    Sun, Hui; Li, Yi; Zhang, Zhi-fen; Ju, Ying; Li, Li; Zhang, Bing-chang; Liu, Bin

    2015-11-01

    Myeloid-derived suppressor cells (MDSCs) are thought to help provide a cellular microenvironments in many solid tumors, in which transformed cells proliferate, acquire new mutations, and evade host immunosurveillance. In the present study, we found that MDSCs (CD33 + CD11b + HLA-DR(low/neg)) in bone marrow were significantly increased in adult acute myeloid leukemia (AML) patients. MDSCs levels in newly diagnosed AML patients correlated well with extramedullary infiltration and plasma D-dimer levels. Remission rates in the MDSCs > 1500 group and MDSCs phenotype. These cells appear to impact the clinical course and prognosis of AML. This data may provide potentially important targets for novel therapies.

  5. Immature myeloid Gr-1+ CD11b+ cells from lipopolysaccharide-immunosuppressed mice acquire inhibitory activity in the bone marrow and migrate to lymph nodes to exert their suppressive function.

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    Landoni, Veronica I; Martire-Greco, Daiana; Rodriguez-Rodrigues, Nahuel; Chiarella, Paula; Schierloh, Pablo; Isturiz, Martin A; Fernández, Gabriela C

    2016-02-01

    Secondary infections due to post-sepsis immunosuppression are a major cause of death in patients with sepsis. Repetitive inoculation of increasing doses of lipopolysaccharide (LPS) into mice mimics the immunosuppression associated with sepsis. Myeloid-derived suppressor cells (MDSCs, Gr-1(+) CD11b(+)) are considered a major component of the immunosuppressive network, interfering with T-cell responses in many pathological conditions. We used LPS-immunosuppressed (IS) mice to address whether MDSCs acquired their suppressive ability in the bone marrow (BM) and whether they could migrate to lymph nodes (LNs) to exert their suppressive function. Our results showed that Gr-1(+) CD11b(+) cells of IS mice already had the potential to inhibit T-cell proliferation in the BM. Moreover, soluble factors present in the BM from IS mice were responsible for inducing this inhibitory ability in control BM cells. In addition, migration of Gr-1(+) CD11b(+) to LNs in vivo was maximal when cells obtained from the BM of IS mice were inoculated into an IS context. In this regard, we found chemoattractant activity in cell-free LN extracts (LNEs) from IS mice and an increased expression of the LN-homing chemokine receptor C-C chemokine receptor type 7 (CCR7) in IS BM Gr-1(+) CD11b(+) cells. These results indicate that Gr-1(+) CD11b(+) cells found in BM from IS mice acquire their suppressive activity in the same niche where they are generated, and migrate to LNs to exert their inhibitory role. A better understanding of MDSC generation and/or regulation of factors able to induce their inhibitory function may provide new and more effective tools for the treatment of sepsis-associated immunosuppression.

  6. Nanoparticle Systems Modulating Myeloid-Derived Suppressor Cells for Cancer Immunotherapy.

    Science.gov (United States)

    Wilkerson, Avia; Kim, Julian; Huang, Alex Y; Zhang, Mei

    2017-01-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that are preferentially expanded in cancer. They arise from myeloid progenitor cells that do not differentiate into mature dendritic cells (DCs), granulocytes, or macrophages, and are rather thought to play a pivotal role in immune escape and cancer progression. MDSCs are characterized by the ability to suppress T cell proliferation and cytotoxicity, inhibit natural killer T (NKT) cell activation, and induce the differentiation and expansion of regulatory T cells (Treg). MDSC levels have been shown to correlate negatively with prognosis and overall survival of patients with cancers of various types and stages. The role of MDSCs in cancer progression represents a promising target for effective cancer immunotherapy. In this review, we discuss the mechanisms of MDSC functions, their influence on tumor progression and metastasis, and finally focus on up to date nanoparticle approaches that target and antagonize MDSCs in tumor-bearing hosts. The development of multifunctional nanoparticle systems for effective imaging, assessment and manipulation of MDSCs will represent strategic theranostic innovations that may improve cancer staging, therapeutic outcomes, and overall patient survival. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  7. Iron acquisition by Mycobacterium tuberculosis residing within myeloid dendritic cells.

    Science.gov (United States)

    Olakanmi, Oyebode; Kesavalu, Banurekha; Abdalla, Maher Y; Britigan, Bradley E

    2013-12-01

    The pathophysiology of Mycobacterium tuberculosis (M.tb) infection is linked to the ability of the organism to grow within macrophages. Lung myeloid dendritic cells are a newly recognized reservoir of M.tb during infection. Iron (Fe) acquisition is critical for M.tb growth. In vivo, extracellular Fe is chelated to transferrin (TF) and lactoferrin (LF). We previously reported that M.tb replicating in human monocyte-dervied macrophages (MDM) can acquire Fe bound to TF, LF, and citrate, as well as from the MDM cytoplasm. Access of M.tb to Fe may influence its growth in macrophages and dendritic cells. In the present work we confirmed the ability of different strains of M.tb to grow in human myeloid dendritic cells in vitro. Fe acquired by M.tb replicating within dendritic cells from externally added Fe chelates varied with the Fe chelate present in the external media: Fe-citrate > Fe-LF > Fe-TF. Fe acquisition rates from each chelate did not vary over 7 days. M.tb within dendritic cells also acquired Fe from the dendritic cell cytoplasm, with the efficiency of Fe acquisition greater from cytoplasmic Fe sources, regardless of the initial Fe chelate from which that cytoplasmic Fe was derived. Growth and Fe acquisition results with human MDM were similar to those with dendritic cells. M.tb grow and replicate within myeloid dendritic cells in vitro. Fe metabolism of M.tb growing in either MDM or dendritic cells in vitro is influenced by the nature of Fe available and the organism appears to preferentially access cytoplasmic rather than extracellular Fe sources. Whether these in vitro data extend to in vivo conditions should be examined in future studies.

  8. Nf1 Haploinsufficiency Alters Myeloid Lineage Commitment and Function, Leading to Deranged Skeletal Homeostasis.

    Science.gov (United States)

    Rhodes, Steven D; Yang, Hao; Dong, Ruizhi; Menon, Keshav; He, Yongzheng; Li, Zhaomin; Chen, Shi; Staser, Karl W; Jiang, Li; Wu, Xiaohua; Yang, Xianlin; Peng, Xianghong; Mohammad, Khalid S; Guise, Theresa A; Xu, Mingjiang; Yang, Feng-Chun

    2015-10-01

    Although nullizygous loss of NF1 leads to myeloid malignancies, haploinsufficient loss of NF1 (Nf1) has been shown to contribute to osteopenia and osteoporosis which occurs in approximately 50% of neurofibromatosis type 1 (NF1) patients. Bone marrow mononuclear cells of haploinsufficient NF1 patients and Nf1(+/-) mice exhibit increased osteoclastogenesis and accelerated bone turnover; however, the culprit hematopoietic lineages responsible for perpetuating these osteolytic manifestations have yet to be elucidated. Here we demonstrate that conditional inactivation of a single Nf1 allele within the myeloid progenitor cell population (Nf1-LysM) is necessary and sufficient to promote multiple osteoclast gains-in-function, resulting in enhanced osteoclastogenesis and accelerated osteoclast bone lytic activity in response to proresorptive challenge in vivo. Surprisingly, mice conditionally Nf1 heterozygous in mature, terminally differentiated osteoclasts (Nf1-Ctsk) do not exhibit any of these skeletal phenotypes, indicating a critical requirement for Nf1 haploinsufficiency at a more primitive/progenitor stage of myeloid development in perpetuating osteolytic activity. We further identified p21Ras-dependent hyperphosphorylation of Pu.1 within the nucleus of Nf1 haploinsufficient myelomonocytic osteoclast precursors, providing a novel therapeutic target for the potential treatment of NF1 associated osteolytic manifestations.

  9. Engagement of SIRPα inhibits growth and induces programmed cell death in acute myeloid leukemia cells.

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    Mahban Irandoust

    Full Text Available BACKGROUND: Recent studies show the importance of interactions between CD47 expressed on acute myeloid leukemia (AML cells and the inhibitory immunoreceptor, signal regulatory protein-alpha (SIRPα on macrophages. Although AML cells express SIRPα, its function has not been investigated in these cells. In this study we aimed to determine the role of the SIRPα in acute myeloid leukemia. DESIGN AND METHODS: We analyzed the expression of SIRPα, both on mRNA and protein level in AML patients and we further investigated whether the expression of SIRPα on two low SIRPα expressing AML cell lines could be upregulated upon differentiation of the cells. We determined the effect of chimeric SIRPα expression on tumor cell growth and programmed cell death by its triggering with an agonistic antibody in these cells. Moreover, we examined the efficacy of agonistic antibody in combination with established antileukemic drugs. RESULTS: By microarray analysis of an extensive cohort of primary AML samples, we demonstrated that SIRPα is differentially expressed in AML subgroups and its expression level is dependent on differentiation stage, with high levels in FAB M4/M5 AML and low levels in FAB M0-M3. Interestingly, AML patients with high SIRPα expression had a poor prognosis. Our results also showed that SIRPα is upregulated upon differentiation of NB4 and Kasumi cells. In addition, triggering of SIRPα with an agonistic antibody in the cells stably expressing chimeric SIRPα, led to inhibition of growth and induction of programmed cell death. Finally, the SIRPα-derived signaling synergized with the activity of established antileukemic drugs. CONCLUSIONS: Our data indicate that triggering of SIRPα has antileukemic effect and may function as a potential therapeutic target in AML.

  10. Engagement of SIRPα Inhibits Growth and Induces Programmed Cell Death in Acute Myeloid Leukemia Cells

    Science.gov (United States)

    Hubeek, Isabelle; van Beek, Ellen M.; Schornagel, Karin; Broekhuizen, Aart J. F.; Akyuz, Mercan; van de Loosdrecht, Arjan A.; Delwel, Ruud; Valk, Peter J.; Sonneveld, Edwin; Kearns, Pamela; Creutzig, Ursula; Reinhardt, Dirk; de Bont, Eveline S. J. M.; Coenen, Eva A.; van den Heuvel-Eibrink, Marry M.; Zwaan, C. Michel; Kaspers, Gertjan J. L.; Cloos, Jacqueline; van den Berg, Timo K.

    2013-01-01

    Background Recent studies show the importance of interactions between CD47 expressed on acute myeloid leukemia (AML) cells and the inhibitory immunoreceptor, signal regulatory protein-alpha (SIRPα) on macrophages. Although AML cells express SIRPα, its function has not been investigated in these cells. In this study we aimed to determine the role of the SIRPα in acute myeloid leukemia. Design and Methods We analyzed the expression of SIRPα, both on mRNA and protein level in AML patients and we further investigated whether the expression of SIRPα on two low SIRPα expressing AML cell lines could be upregulated upon differentiation of the cells. We determined the effect of chimeric SIRPα expression on tumor cell growth and programmed cell death by its triggering with an agonistic antibody in these cells. Moreover, we examined the efficacy of agonistic antibody in combination with established antileukemic drugs. Results By microarray analysis of an extensive cohort of primary AML samples, we demonstrated that SIRPα is differentially expressed in AML subgroups and its expression level is dependent on differentiation stage, with high levels in FAB M4/M5 AML and low levels in FAB M0–M3. Interestingly, AML patients with high SIRPα expression had a poor prognosis. Our results also showed that SIRPα is upregulated upon differentiation of NB4 and Kasumi cells. In addition, triggering of SIRPα with an agonistic antibody in the cells stably expressing chimeric SIRPα, led to inhibition of growth and induction of programmed cell death. Finally, the SIRPα-derived signaling synergized with the activity of established antileukemic drugs. Conclusions Our data indicate that triggering of SIRPα has antileukemic effect and may function as a potential therapeutic target in AML. PMID:23320069

  11. Distinct functions of epidermal and myeloid-derived VEGF-A in skin tumorigenesis mediated by HPV8.

    Science.gov (United States)

    Ding, Xiaolei; Lucas, Tina; Marcuzzi, Gian P; Pfister, Herbert; Eming, Sabine A

    2015-01-15

    Beta human papillomaviruses (HPV) have been suspected to be carcinogenic in nonmelanoma skin cancers (NMSC), but the basis for potential viral contributions to these cancers is poorly understood. In particular, it is unresolved how HPV-infected keratinocytes escape cell-cycle control and whether their cross-talk with immune cells is critical for tumorigenesis. In nonviral preclinical models, the angiogenic cytokine VEGF-A has been identified as a critical regulator of NMSC. In this study, we dissected the contribution of epidermal versus myeloid cell-derived VEGF-A in HPV-mediated skin cancer by interbreeding an HPV8 transgenic mouse model with a conditional disruption of VEGF-A restricted to either epidermal or myeloid cells. Although only epidermal-derived VEGF-A was essential for initiation of skin tumor development, both spontaneously and UV-light triggered, both epidermal and myeloid cell-derived VEGF-A contributed to regeneration-induced tumorigenesis upon HPV8 overexpression, partly not only through a paracrine effect on endothelial cells, but also most probably through an additional autocrine effect on epidermal cells. Our findings offer new mechanistic insights into distinct functions of epidermal versus myeloid cell-derived VEGF-A during HPV-mediated tumorigenesis, with possible implications for preventing this disease.

  12. Heterozygous inactivation of the Nf1 gene in myeloid cells enhances neointima formation via a rosuvastatin-sensitive cellular pathway.

    Science.gov (United States)

    Stansfield, Brian K; Bessler, Waylan K; Mali, Raghuveer; Mund, Julie A; Downing, Brandon; Li, Fang; Sarchet, Kara N; DiStasi, Matthew R; Conway, Simon J; Kapur, Reuben; Ingram, David A

    2013-03-01

    Mutations in the NF1 tumor suppressor gene cause Neurofibromatosis type 1 (NF1). Neurofibromin, the protein product of NF1, functions as a negative regulator of Ras activity. Some NF1 patients develop cardiovascular disease, which represents an underrecognized disease complication and contributes to excess morbidity and mortality. Specifically, NF1 patients develop arterial occlusion resulting in tissue ischemia and sudden death. Murine studies demonstrate that heterozygous inactivation of Nf1 (Nf1(+/-)) in bone marrow cells enhances neointima formation following arterial injury. Macrophages infiltrate Nf1(+/-) neointimas, and NF1 patients have increased circulating inflammatory monocytes in their peripheral blood. Therefore, we tested the hypothesis that heterozygous inactivation of Nf1 in myeloid cells is sufficient for neointima formation. Specific ablation of a single copy of the Nf1 gene in myeloid cells alone mobilizes a discrete pro-inflammatory murine monocyte population via a cell autonomous and gene-dosage dependent mechanism. Furthermore, lineage-restricted heterozygous inactivation of Nf1 in myeloid cells is sufficient to reproduce the enhanced neointima formation observed in Nf1(+/-) mice when compared with wild-type controls, and homozygous inactivation of Nf1 in myeloid cells amplified the degree of arterial stenosis after arterial injury. Treatment of Nf1(+/-) mice with rosuvastatin, a stain with anti-inflammatory properties, significantly reduced neointima formation when compared with control. These studies identify neurofibromin-deficient myeloid cells as critical cellular effectors of Nf1(+/-) neointima formation and propose a potential therapeutic for NF1 cardiovascular disease.

  13. Specific Btk inhibition suppresses B cell- and myeloid cell-mediated arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Di Paolo, Julie A.; Huang, Tao; Balazs, Mercedesz; Barbosa, James; Barck, Kai H.; Bravo, Brandon J.; Carano, Richard A.D.; Darrow, James; Davies, Douglas R.; DeForge, Laura E.; Diehl, Lauri; Ferrando, Ronald; Gallion, Steven L.; Giannetti, Anthony M.; Gribling, Peter; Hurez, Vincent; Hymowitz, Sarah G.; Jones, Randall; Kropf, Jeffrey E.; Lee, Wyne P.; Maciejewski, Patricia M.; Mitchell, Scott A.; Rong, Hong; Staker, Bart L.; Whitney, J. Andrew; Yeh, Sherry; Young, Wendy B.; Yu, Christine; Zhang, Juan; Reif, Karin; Currie, Kevin S. (CGI); (Emerald); (Genentech)

    2011-09-20

    Bruton's tyrosine kinase (Btk) is a therapeutic target for rheumatoid arthritis, but the cellular and molecular mechanisms by which Btk mediates inflammation are poorly understood. Here we describe the discovery of CGI1746, a small-molecule Btk inhibitor chemotype with a new binding mode that stabilizes an inactive nonphosphorylated enzyme conformation. CGI1746 has exquisite selectivity for Btk and inhibits both auto- and transphosphorylation steps necessary for enzyme activation. Using CGI1746, we demonstrate that Btk regulates inflammatory arthritis by two distinct mechanisms. CGI1746 blocks B cell receptor-dependent B cell proliferation and in prophylactic regimens reduces autoantibody levels in collagen-induced arthritis. In macrophages, Btk inhibition abolishes Fc{gamma}RIII-induced TNF{alpha}, IL-1{beta} and IL-6 production. Accordingly, in myeloid- and Fc{gamma}R-dependent autoantibody-induced arthritis, CGI1746 decreases cytokine levels within joints and ameliorates disease. These results provide new understanding of the function of Btk in both B cell- or myeloid cell-driven disease processes and provide a compelling rationale for targeting Btk in rheumatoid arthritis.

  14. Targeting DNA vaccines to myeloid cells using a small peptide.

    Science.gov (United States)

    Ye, Chunting; Choi, Jang Gi; Abraham, Sojan; Shankar, Premlata; Manjunath, N

    2015-01-01

    Targeting DNA vaccines to dendritic cells (DCs) greatly enhances immunity. Although several approaches have been used to target protein Ags to DCs, currently there is no method that targets DNA vaccines directly to DCs. Here, we show that a small peptide derived from the rabies virus glycoprotein fused to protamine residues (RVG-P) can target DNA to myeloid cells, including DCs, which results in enhanced humoral and T-cell responses. DCs targeted with a DNA vaccine encoding the immunodominant vaccinia B8R gene via RVG-P were able to restimulate vaccinia-specific memory T cells in vitro. Importantly, a single i.v. injection of B8R gene bound to RVG-P was able to prime a vaccinia-specific T-cell response that was able to rapidly clear a subsequent vaccinia challenge in mice. Moreover, delivery of DNA in DCs was enough to induce DC maturation and efficient Ag presentation without the need for adjuvants. Finally, immunization of mice with a DNA-vaccine encoding West Nile virus (WNV) prM and E proteins via RVG-P elicited high titers of WNV-neutralizing Abs that protected mice from lethal WNV challenge. Thus, RVG-P provides a reagent to target DNA vaccines to myeloid cells and elicit robust T-cell and humoral immune responses.

  15. Hepatic ischemia and reperfusion injury in the absence of myeloid cell-derived COX-2 in mice.

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    Sergio Duarte

    Full Text Available Cyclooxygenase-2 (COX-2 is a mediator of hepatic ischemia and reperfusion injury (IRI. While both global COX-2 deletion and pharmacologic COX-2 inhibition ameliorate liver IRI, the clinical use of COX-2 inhibitors has been linked to increased risks of heart attack and stroke. Therefore, a better understanding of the role of COX-2 in different cell types may lead to improved therapeutic strategies for hepatic IRI. Macrophages of myeloid origin are currently considered to be important sources of the COX-2 in damaged livers. Here, we used a Cox-2flox conditional knockout mouse (COX-2-M/-M to examine the function of COX-2 expression in myeloid cells during liver IRI. COX-2-M/-M mice and their WT control littermates were subjected to partial liver ischemia followed by reperfusion. COX-2-M/-M macrophages did not express COX-2 upon lipopolysaccharide stimulation and COX-2-M/-M livers showed reduced levels of COX-2 protein post-IRI. Nevertheless, selective deletion of myeloid cell-derived COX-2 failed to ameliorate liver IRI; serum transaminases and histology were comparable in both COX-2-M/-M and WT mice. COX-2-M/-M livers, like WT livers, developed extensive necrosis, vascular congestion, leukocyte infiltration and matrix metalloproteinase-9 (MMP-9 expression post-reperfusion. In addition, myeloid COX-2 deletion led to a transient increase in IL-6 levels after hepatic reperfusion, when compared to controls. Administration of celecoxib, a selective COX-2 inhibitor, resulted in significantly improved liver function and histology in both COX-2-M/-M and WT mice post-reperfusion, providing evidence that COX-2-mediated liver IRI is caused by COX-2 derived from a source(s other than myeloid cells. In conclusion, these results support the view that myeloid COX-2, including myeloid-macrophage COX-2, is not responsible for the hepatic IRI phenotype.

  16. Myeloid dendritic cells are potential players in human neurodegenerative diseases

    Directory of Open Access Journals (Sweden)

    Paola eBossù

    2015-12-01

    Full Text Available Alzheimer’s (AD and Parkinson’s (PD diseases are devastating neurodegenerative disturbances wherein neuroinflammation is a chronic pathogenic process with high therapeutic potential. Major mediators of AD/PD neuroimmune processes are resident immune cells, but immune cells derived from periphery may also participate and to some extent modify neuroinflammation. Specifically, blood borne myeloid cells emerge as crucial components of AD/PD progression and susceptibility. Among these, dendritic cells (DCs are key immune orchestrators and players of brain immune surveillance: we candidate them as potential mediators of both AD and PD and as relevant cell model for unraveling myeloid cell role in neurodegeneration. Hence, we recapitulate and discuss emerging data suggesting that blood-derived DCs play a role in experimental and human neurodegenerative diseases. In humans, in particular, DCs are modified by in vitro culture with neurodegeneration-associated pathogenic factors and dysregulated in AD patients, while the levels of DC precursors are decreased in AD and PD patients’ blood, possibly as an index of their recruitment to the brain. Overall, we emphasize the need to explore the impact of DCs on neurodegeneration to uncover peripheral immune mechanisms of pathogenic importance, recognize potential biomarkers and improve therapeutic approaches for neurodegenerative diseases.

  17. ATM facilitates mouse gammaherpesvirus reactivation from myeloid cells during chronic infection.

    Science.gov (United States)

    Kulinski, Joseph M; Darrah, Eric J; Broniowska, Katarzyna A; Mboko, Wadzanai P; Mounce, Bryan C; Malherbe, Laurent P; Corbett, John A; Gauld, Stephen B; Tarakanova, Vera L

    2015-09-01

    Gammaherpesviruses are cancer-associated pathogens that establish life-long infection in most adults. Insufficiency of Ataxia-Telangiectasia mutated (ATM) kinase leads to a poor control of chronic gammaherpesvirus infection via an unknown mechanism that likely involves a suboptimal antiviral response. In contrast to the phenotype in the intact host, ATM facilitates gammaherpesvirus reactivation and replication in vitro. We hypothesized that ATM mediates both pro- and antiviral activities to regulate chronic gammaherpesvirus infection in an immunocompetent host. To test the proposed proviral activity of ATM in vivo, we generated mice with ATM deficiency limited to myeloid cells. Myeloid-specific ATM deficiency attenuated gammaherpesvirus infection during the establishment of viral latency. The results of our study uncover a proviral role of ATM in the context of gammaherpesvirus infection in vivo and support a model where ATM combines pro- and antiviral functions to facilitate both gammaherpesvirus-specific T cell immune response and viral reactivation in vivo.

  18. The role of Lin28b in myeloid and mast cell differentiation and mast cell malignancy.

    Science.gov (United States)

    Wang, L D; Rao, T N; Rowe, R G; Nguyen, P T; Sullivan, J L; Pearson, D S; Doulatov, S; Wu, L; Lindsley, R C; Zhu, H; DeAngelo, D J; Daley, G Q; Wagers, A J

    2015-06-01

    Mast cells (MCs) are critical components of the innate immune system and important for host defense, allergy, autoimmunity, tissue regeneration and tumor progression. Dysregulated MC development leads to systemic mastocytosis (SM), a clinically variable but often devastating family of hematologic disorders. Here we report that induced expression of Lin28, a heterochronic gene and pluripotency factor implicated in driving a fetal hematopoietic program, caused MC accumulation in adult mice in target organs such as the skin and peritoneal cavity. In vitro assays revealed a skewing of myeloid commitment in LIN28B-expressing hematopoietic progenitors, with increased levels of LIN28B in common myeloid and basophil-MC progenitors altering gene expression patterns to favor cell fate choices that enhanced MC specification. In addition, LIN28B-induced MCs appeared phenotypically and functionally immature, and in vitro assays suggested a slowing of MC terminal differentiation in the context of LIN28B upregulation. Finally, interrogation of human MC leukemia samples revealed upregulation of LIN28B in abnormal MCs from patients with SM. This work identifies Lin28 as a novel regulator of innate immune function and a new protein of interest in MC disease.

  19. Gain of cellular adaptation due to prolonged p53 impairment leads to functional switchover from p53 to p73 during DNA damage in acute myeloid leukemia cells.

    Science.gov (United States)

    Chakraborty, Juni; Banerjee, Shuvomoy; Ray, Pallab; Hossain, Dewan Md Sakib; Bhattacharyya, Sankar; Adhikary, Arghya; Chattopadhyay, Sreya; Das, Tanya; Sa, Gaurisankar

    2010-10-22

    Tumor suppressor p53 plays the central role in regulating apoptosis in response to genotoxic stress. From an evolutionary perspective, the activity of p53 has to be backed up by other protein(s) in case of any functional impairment of this protein, to trigger DNA damage-induced apoptosis in cancer cells. We adopted multiple experimental approaches to demonstrate that in p53-impaired cancer cells, DNA damage caused accumulation of p53 paralogue p73 via Chk-1 that strongly impacted Bax expression and p53-independent apoptosis. On the contrary, when p53 function was restored by ectopic expression, Chk-2 induced p53 accumulation that in turn overshadowed p73 activity, suggesting an antagonistic interaction between p53 family members. To understand such interaction better, p53-expressing cells were impaired differentially for p53 activity. In wild-type p53-expressing cancer cells that were silenced for p53 for several generations, p73 was activated, whereas no such trend was observed when p53 was transiently silenced. Prolonged p53 interference, even in functional p53 settings, therefore, leads to the "gain of cellular adaptation" in a way that alters the cellular microenvironment in favor of p73 activation by altering p73-regulatory proteins, e.g. Chk1 activation and dominant negative p73 down-regulation. These findings not only unveil a hitherto unexplained mechanism underlying the functional switchover from p53 to p73, but also validate p73 as a promising and potential target for cancer therapy in the absence of functional p53.

  20. Neurofibromin Deficient Myeloid Cells are Critical Mediators of Aneurysm Formation In Vivo

    Science.gov (United States)

    Li, Fang; Downing, Brandon D.; Smiley, Lucy C.; Mund, Julie A.; DiStasi, Matthew R.; Bessler, Waylan K.; Sarchet, Kara N.; Hinds, Daniel M.; Kamendulis, Lisa M.; Hingtgen, Cynthia M.; Case, Jamie; Clapp, D. Wade; Conway, Simon J.; Stansfield, Brian K.; Ingram, David A.

    2014-01-01

    Background Neurofibromatosis Type 1 (NF1) is a genetic disorder resulting from mutations in the NF1 tumor suppressor gene. Neurofibromin, the protein product of NF1, functions as a negative regulator of Ras activity in circulating hematopoietic and vascular wall cells, which are critical for maintaining vessel wall homeostasis. NF1 patients have evidence of chronic inflammation resulting in development of premature cardiovascular disease, including arterial aneurysms, which may manifest as sudden death. However, the molecular pathogenesis of NF1 aneurysm formation is unknown. Method and Results Utilizing an angiotensin II-induced aneurysm model, we demonstrate that heterozygous inactivation of Nf1 (Nf1+/−) enhanced aneurysm formation with myeloid cell infiltration and increased oxidative stress in the vessel wall. Using lineage-restricted transgenic mice, we show loss of a single Nf1 allele in myeloid cells is sufficient to recapitulate the Nf1+/− aneurysm phenotype in vivo. Finally, oral administration of simvastatin or the antioxidant apocynin, reduced aneurysm formation in Nf1+/− mice. Conclusion These data provide genetic and pharmacologic evidence that Nf1+/− myeloid cells are the cellular triggers for aneurysm formation in a novel model of NF1 vasculopathy and provide a potential therapeutic target. PMID:24370551

  1. Gain of Cellular Adaptation Due to Prolonged p53 Impairment Leads to Functional Switchover from p53 to p73 during DNA Damage in Acute Myeloid Leukemia Cells*

    OpenAIRE

    2010-01-01

    Tumor suppressor p53 plays the central role in regulating apoptosis in response to genotoxic stress. From an evolutionary perspective, the activity of p53 has to be backed up by other protein(s) in case of any functional impairment of this protein, to trigger DNA damage-induced apoptosis in cancer cells. We adopted multiple experimental approaches to demonstrate that in p53-impaired cancer cells, DNA damage caused accumulation of p53 paralogue p73 via Chk-1 that strongly impacted Bax expressi...

  2. The DC-HIL/syndecan-4 pathway regulates autoimmune responses through myeloid-derived suppressor cells.

    Science.gov (United States)

    Chung, Jin-Sung; Tamura, Kyoichi; Akiyoshi, Hideo; Cruz, Ponciano D; Ariizumi, Kiyoshi

    2014-03-15

    Having discovered that the dendritic cell (DC)-associated heparan sulfate proteoglycan-dependent integrin ligand (DC-HIL) receptor on APCs inhibits T cell activation by binding to syndecan-4 (SD-4) on T cells, we hypothesized that the DC-HIL/SD-4 pathway may regulate autoimmune responses. Using experimental autoimmune encephalomyelitis (EAE) as a disease model, we noted an increase in SD-4(+) T cells in lymphoid organs of wild-type (WT) mice immunized for EAE. The autoimmune disease was also more severely induced (clinically, histologically, and immunophenotypically) in mice knocked out for SD-4 compared with WT cohorts. Moreover, infusion of SD-4(-/-) naive T cells during EAE induction into Rag2(-/-) mice also led to increased severity of EAE in these animals. Similar to SD-4 on T cells, DC-HIL expression was upregulated on myeloid cells during EAE induction, with CD11b(+)Gr-1(+) myeloid-derived suppressor cells (MDSCs) as the most expanded population and most potent T cell suppressor among the myeloid cells examined. The critical role of DC-HIL was supported by DC-HIL gene deletion or anti-DC-HIL treatment, which abrogated T cell suppressor activity of MDSCs, and also by DC-HIL activation inducing MDSC expression of IFN-γ, NO, and reactive oxygen species. Akin to SD-4(-/-) mice, DC-HIL(-/-) mice manifested exacerbated EAE. Adoptive transfer of MDSCs from EAE-affected WT mice into DC-HIL(-/-) mice reduced EAE severity to the level of EAE-immunized WT mice, an outcome that was precluded by depleting DC-HIL(+) cells from the infused MDSC preparation. Our findings indicate that the DC-HIL/SD-4 pathway regulates autoimmune responses by mediating the T cell suppressor function of MDSCs.

  3. Camptothecin and khat (Catha edulis Forsk. induced distinct cell death phenotypes involving modulation of c-FLIPL, Mcl-1, procaspase-8 and mitochondrial function in acute myeloid leukemia cell lines

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    Fossan Kjell O

    2009-11-01

    Full Text Available Abstract Background An organic extract of the recreational herb khat (Catha edulis Forsk. triggers cell death in various leukemia cell lines in vitro. The chemotherapeutics camptothecin, a plant alkaloid topoisomerase I inhibitor, was tested side-by-side with khat in a panel of acute myeloid leukemia cell lines to elucidate mechanisms of toxicity. Results Khat had a profound effect on MOLM-13 cells inducing mitochondrial damage, chromatin margination and morphological features of autophagy. The effects of khat on mitochondrial ultrastructure in MOLM-13 correlated with strongly impaired routine respiration, an effect neither found in the khat-resistant MV-4-11 cells nor in camptothecin treated cells. Enforced expression of anti-apoptotic Bcl-2 protein provided protection against camptothecin-induced cell death and partly against khat toxicity. Khat-induced cell death in MOLM-13 cells included reduced levels of anti-apoptotic Mcl-1 protein, while both khat and camptothecin induced c-FLIPL cleavage and procaspase-8 activation. Conclusion Khat activated a distinct cell death pathway in sensitive leukemic cells as compared to camptothecin, involving mitochondrial damage and morphological features of autophagy. This suggests that khat should be further explored in the search for novel experimental therapeutics.

  4. The Role of Myeloid-Derived Suppressor Cells in Immune Ontogeny

    Science.gov (United States)

    Gantt, Soren; Gervassi, Ana; Jaspan, Heather; Horton, Helen

    2014-01-01

    Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of granulocytic or monocytic cells that suppress innate as well as adaptive immune responses. In healthy adults, immature myeloid cells differentiate into macrophages, dendritic cells, and granulocytes in the bone marrow and MDSC are rarely detected in peripheral blood. However, in certain pathologies, in particular malignancies and chronic infection, differentiation of these cells is altered resulting in accumulation of circulating suppressive myeloid cells. MDSC express suppressive factors such as arginase-1, reactive oxygen species, and inducible nitric oxide synthase, which have the ability to inhibit T cell proliferation and cytoxicity, induce the expansion of regulatory T cells, and block natural killer cell activation. It is increasingly recognized that MDSC alter the immune response to several cancers, and perhaps chronic viral infections, in clinically important ways. In this review, we outline the potential contribution of MDSC to the generation of feto-maternal tolerance and to the ineffective immune responses to many infections and vaccines observed in early post-natal life. Granulocytic MDSC are present in large numbers in pregnant women and in cord blood, and wane rapidly during infancy. Furthermore, cord blood MDSC suppress in vitro T cell and NK responses, suggesting that they may play a significant role in human immune ontogeny. However, there are currently no data that demonstrate in vivo effects of MDSC on feto-maternal tolerance or immune ontogeny. Studies are ongoing to evaluate the functional importance of MDSC, including their effects on control of infection and response to vaccination in infancy. Importantly, several pharmacologic interventions have the potential to reverse MDSC function. Understanding the role of MDSC in infant ontogeny and their mechanisms of action could lead to interventions that reduce mortality due to early-life infections. PMID:25165466

  5. The role of myeloid-derived suppressor cells in immune ontogeny

    Directory of Open Access Journals (Sweden)

    Soren eGantt

    2014-08-01

    Full Text Available Myeloid derived suppressor cells (MDSC are a heterogeneous population of granulocytic or monocytic cells that suppress innate as well as adaptive immune responses. In healthy adults, immature myeloid cells differentiate into macrophages, dendritic cells, and granulocytes in the bone marrow, and MDSC are rarely detected in peripheral blood. However, in certain pathologies, in particular malignancies and chronic infection, differentiation of these cells is altered resulting in accumulation of circulating suppressive myeloid cells. MDSC express suppressive factors such as arginase-1, reactive oxygen species, and inducible nitric oxide synthase, which have the ability to inhibit T cell proliferation and cytoxicity, induce the expansion of regulatory T cells, and block natural killer cell activation. It is increasingly recognized that MDSC alter the immune response to several cancers, and perhaps chronic viral infections, in clinically important ways. In this review, we outline the potential contribution of MDSC to the generation of feto-maternal tolerance and to the ineffective immune responses to many infections and vaccines observed in early post-natal life. Granulocytic MDSC are present in large numbers in pregnant women and in cord blood, and wane rapidly during infancy. Furthermore, cord blood MDSC suppress in vitro T cell and NK responses, suggesting that they may play a significant role in human immune ontogeny. However, there are currently no data that demonstrate in vivo effects of MDSC on feto-maternal tolerance or immune ontogeny. Studies are ongoing to evaluate the functional importance of MDSC, including their effects on control of infection and response to vaccination in infancy. Importantly, several pharmacologic interventions have the potential to reverse MDSC function. Understanding the role of MDSC in infant ontogeny and their mechanisms of action could lead to interventions that reduce mortality due to early-life infections.

  6. The role of myeloid-derived suppressor cells in immune ontogeny.

    Science.gov (United States)

    Gantt, Soren; Gervassi, Ana; Jaspan, Heather; Horton, Helen

    2014-01-01

    Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of granulocytic or monocytic cells that suppress innate as well as adaptive immune responses. In healthy adults, immature myeloid cells differentiate into macrophages, dendritic cells, and granulocytes in the bone marrow and MDSC are rarely detected in peripheral blood. However, in certain pathologies, in particular malignancies and chronic infection, differentiation of these cells is altered resulting in accumulation of circulating suppressive myeloid cells. MDSC express suppressive factors such as arginase-1, reactive oxygen species, and inducible nitric oxide synthase, which have the ability to inhibit T cell proliferation and cytoxicity, induce the expansion of regulatory T cells, and block natural killer cell activation. It is increasingly recognized that MDSC alter the immune response to several cancers, and perhaps chronic viral infections, in clinically important ways. In this review, we outline the potential contribution of MDSC to the generation of feto-maternal tolerance and to the ineffective immune responses to many infections and vaccines observed in early post-natal life. Granulocytic MDSC are present in large numbers in pregnant women and in cord blood, and wane rapidly during infancy. Furthermore, cord blood MDSC suppress in vitro T cell and NK responses, suggesting that they may play a significant role in human immune ontogeny. However, there are currently no data that demonstrate in vivo effects of MDSC on feto-maternal tolerance or immune ontogeny. Studies are ongoing to evaluate the functional importance of MDSC, including their effects on control of infection and response to vaccination in infancy. Importantly, several pharmacologic interventions have the potential to reverse MDSC function. Understanding the role of MDSC in infant ontogeny and their mechanisms of action could lead to interventions that reduce mortality due to early-life infections.

  7. Biology and relevance of human acute myeloid leukemia stem cells.

    Science.gov (United States)

    Thomas, Daniel; Majeti, Ravindra

    2017-03-23

    Evidence of human acute myeloid leukemia stem cells (AML LSCs) was first reported nearly 2 decades ago through the identification of rare subpopulations of engrafting cells in xenotransplantation assays. These AML LSCs were shown to reside at the apex of a cellular hierarchy that initiates and maintains the disease, exhibiting properties of self-renewal, cell cycle quiescence, and chemoresistance. This cancer stem cell model offers an explanation for chemotherapy resistance and disease relapse and implies that approaches to treatment must eradicate LSCs for cure. More recently, a number of studies have both refined and expanded our understanding of LSCs and intrapatient heterogeneity in AML using improved xenotransplant models, genome-scale analyses, and experimental manipulation of primary patient cells. Here, we review these studies with a focus on the immunophenotype, biological properties, epigenetics, genetics, and clinical associations of human AML LSCs and discuss critical questions that need to be addressed in future research. © 2017 by The American Society of Hematology.

  8. Gene expression profiling to define the cell intrinsic role of the SKI proto-oncogene in hematopoiesis and myeloid neoplasms.

    Science.gov (United States)

    Chalk, Alistair M; Liddicoat, Brian J J; Walkley, Carl R; Singbrant, Sofie

    2014-12-01

    The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced gene signatures associated with hematopoietic stem cells and myeloid differentiation. Here we provide detailed experimental methods and analysis for the gene expression profiling described in our recently published study of Singbrant et al. (2014) in Haematologica. Our data sets (available at http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE39457) provide a resource for exploring the underlying molecular mechanisms of the involvement of the proto-oncogene SKI in hematopoietic stem cell function and development of myeloid neoplasms.

  9. Gene expression profiling to define the cell intrinsic role of the SKI proto-oncogene in hematopoiesis and myeloid neoplasms

    Directory of Open Access Journals (Sweden)

    Alistair M. Chalk

    2014-12-01

    Full Text Available The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced gene signatures associated with hematopoietic stem cells and myeloid differentiation. Here we provide detailed experimental methods and analysis for the gene expression profiling described in our recently published study of Singbrant et al. (2014 in Haematologica. Our data sets (available at http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE39457 provide a resource for exploring the underlying molecular mechanisms of the involvement of the proto-oncogene SKI in hematopoietic stem cell function and development of myeloid neoplasms.

  10. Myeloid-derived suppressor cells impair the quality of dendritic cell vaccines.

    Science.gov (United States)

    Poschke, I; Mao, Y; Adamson, L; Salazar-Onfray, F; Masucci, G; Kiessling, R

    2012-06-01

    Myeloid-derived suppressor cells (MDSC) are important regulators of the immune system and key players in tumor-induced suppression of T-cell responses. CD14+HLA-DR-/low MDSC have been detected in a great number of malignancies, including melanoma. MDSC are known to be impaired in their ability to differentiate along the myeloid lineage, e.g., into dendritic cells (DC). This is a concern for utilization of monocyte-derived DC for vaccination of patients with melanoma or other cancers exhibiting accumulation of CD14+ MDSC. When producing DC according to standard operating procedures of two currently ongoing clinical trials, we found that MDSC co-purified with monocytes isolated by elutriation. MDSC frequencies did not affect yield or viability of the produced DC, but induced a dose-dependent decrease in DC maturation, ability to take up antigen, migrate and induce T-cell IFNγ production. Changes in DC characteristics were most notable when 'pathological' frequencies of >50% CD14+HLA-DR- cells were present in the starting culture. The impaired DC quality could not be explained by altered cytokine production or increased oxidative stress in the cultures. Tracking of HLA-DR- cells throughout the culture period revealed that the observed changes were partially due to the impaired maturation and functionality of the originally HLA-DR- population, but also to their negative effects on HLA-DR+ cells. In conclusion, MDSC could be induced to differentiate into DC but, due to the impairment of overall DC vaccine quality when >50% HLA-DR- cells were present in the starting culture, their removal could be advisable.

  11. Granulocytic subset of myeloid derived suppressor cells in rats with mammary carcinoma

    NARCIS (Netherlands)

    Dolen, Y.; Gunaydin, G.; Esendagli, G.; Guc, D.

    2015-01-01

    Limited knowledge is available on myeloid derived suppressor cells (MDSCs) of rat origin. We examined the myeloid cells from peripheral blood, bone marrow and spleens of healthy and mammary tumor bearing rats employing a novel immunophenotyping strategy with CD172a, HIS48, and Rp-1 antibodies. We ad

  12. Tissue type plasminogen activator regulates myeloid-cell dependent neoangiogenesis during tissue regeneration

    DEFF Research Database (Denmark)

    Ohki, Makiko; Ohki, Yuichi; Ishihara, Makoto

    2010-01-01

    tissue regeneration is not well understood. Bone marrow (BM)-derived myeloid cells facilitate angiogenesis during tissue regeneration. Here, we report that a serpin-resistant form of tPA by activating the extracellular proteases matrix metalloproteinase-9 and plasmin expands the myeloid cell pool...

  13. Specific Btk inhibition suppresses B cell- and myeloid cell-mediated arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Di Paolo, Julie A; Huang, Tao; Balazs, Mercedesz; Barbosa, James; Barck, Kai H; Bravo, Brandon J; Carano, Richard A.D.; Darrow, James; Davies, Douglas R; DeForge, Laura E; Diehl, Lauri; Ferrando, Ronald; Gallion, Steven L; Giannetti, Anthony M; Gribling, Peter; Hurez, Vincent; Hymowitz, Sarah G; Jones, Randall; Kropf, Jeffrey E; Lee, Wyne P; Maciejewski, Patricia M; Mitchell, Scott A; Rong, Hong; Staker, Bart L; Whitney, J Andrew; Yeh, Sherry; Young, Wendy B; Yu, Christine; Zhang, Juan; Reif, Karin; Currie, Kevin S [CGI; (Emerald); (Genentech)

    2011-08-29

    Bruton's tyrosine kinase (Btk) is a therapeutic target for rheumatoid arthritis, but the cellular and molecular mechanisms by which Btk mediates inflammation are poorly understood. Here we describe the discovery of CGI1746, a small-molecule Btk inhibitor chemotype with a new binding mode that stabilizes an inactive nonphosphorylated enzyme conformation. CGI1746 has exquisite selectivity for Btk and inhibits both auto- and transphosphorylation steps necessary for enzyme activation. Using CGI1746, we demonstrate that Btk regulates inflammatory arthritis by two distinct mechanisms. CGI1746 blocks B cell receptor–dependent B cell proliferation and in prophylactic regimens reduces autoantibody levels in collagen-induced arthritis. In macrophages, Btk inhibition abolishes FcγRIII-induced TNFα, IL-1β and IL-6 production. Accordingly, in myeloid- and FcγR-dependent autoantibody-induced arthritis, CGI1746 decreases cytokine levels within joints and ameliorates disease. These results provide new understanding of the function of Btk in both B cell– or myeloid cell–driven disease processes and provide a compelling rationale for targeting Btk in rheumatoid arthritis.

  14. Alantolactone selectively ablates acute myeloid leukemia stem and progenitor cells

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    Yahui Ding

    2016-09-01

    Full Text Available Abstract Background The poor outcomes for patients diagnosed with acute myeloid leukemia (AML are largely attributed to leukemia stem cells (LSCs which are difficult to eliminate with conventional therapy and responsible for relapse. Thus, new therapeutic strategies which could selectively target LSCs in clinical leukemia treatment and avoid drug resistance are urgently needed. However, only a few small molecules have been reported to show anti-LSCs activity. Methods The aim of the present study was to identify alantolactone as novel agent that can ablate acute myeloid leukemia stem and progenitor cells from AML patient specimens and evaluate the anticancer activity of alantolactone in vitro and in vivo. Results The present study is the first to demonstrate that alantolactone, a prominent eudesmane-type sesquiterpene lactone, could specifically ablate LSCs from AML patient specimens. Furthermore, in comparison to the conventional chemotherapy drug, cytosine arabinoside (Ara-C, alantolactone showed superior effects of leukemia cytotoxicity while sparing normal hematopoietic cells. Alantolactone induced apoptosis with a dose-dependent manner by suppression of NF-kB and its downstream target proteins. DMA-alantolactone, a water-soluble prodrug of alantolactone, could suppress tumor growth in vivo. Conclusions Based on these results, we propose that alantolactone may represent a novel LSCs-targeted therapy and eudesmane-type sesquiterpene lactones offer a new scaffold for drug discovery towards anti-LSCs agents.

  15. Icariin and its derivative, ICT, exert anti-inflammatory, anti-tumor effects, and modulate myeloid derived suppressive cells (MDSCs) functions.

    Science.gov (United States)

    Zhou, Junmin; Wu, Jinfeng; Chen, Xianghong; Fortenbery, Nicole; Eksioglu, Erika; Kodumudi, Krithika N; Pk, Epling-Burnette; Dong, Jingcheng; Djeu, Julie Y; Wei, Sheng

    2011-07-01

    3, 5,7-trihydroxy-4'-methoxy-8-(3-hydroxy-3-methylbutyl)-flavone (ICT) is a novel derivative of Icariin (ICA), the major active ingredient of Herba Epimedii, a herb used in traditional Chinese and alternative medicine. We previously demonstrated its anti-inflammatory effect in murine innate immune cells and activated human PBMCs. We report herein that ICA or ICT treatment reduces the expression of MRP8/MRP14 and toll-like receptor 4 (TLR4) on human PBMCs. Administration of ICA or ICT inhibited tumor growth in 4T1-Neu tumor-bearing mice and considerably decreased MDSC numbers in the spleen of these mice. Further, we saw a restoration of IFN-γ production by CD8+ T cells in tumor bearing mice when treated with ICA or ICT. ICA and ICT significantly decreased the amounts of nitric oxide and reactive oxygen species in MDSC in vivo. When MDSC were treated in vitro with ICT, we saw a significant reduction in the percent of these cells with concomitant differentiation into dendritic cells and macrophages. Concomitant with this cell type conversion was a down-regulation of IL-10, IL-6 and TNF-α production. Decreased expression of S100A8/9 and inhibition of activation of STAT3 and AKT may in part be responsible for the observed results. In conclusion, our results showed that ICA, and more robustly, ICT, directly modulate MDSC signaling and therefore altered the phenotype and function of these cells, in vitro and in vivo.

  16. The normal flora may contribute to the quantitative preponderance of myeloid cells under physiological conditions.

    Science.gov (United States)

    Liang, Shi; LiHua, Hu

    2011-01-01

    Under physiological conditions, the innate immune cells derived from myeloid lineage absolutely outnumber the lymphoid cells. At present, two theories are attributed to the maintenance of haemopoiesis: the asymmetric cell division and the bone marrow hematopoietic microenvironment or "niche". However, the former only explains the self-renewal of haemopoietic stem cell (HSC) and the start of haemopoietic differentiation but fails to address the inducers of cell fate decisions; the latter has to admit that the hematopoietic cytokines, despite their significance in the maintenance of haemopoiesis, have no specific effect on lineage commitment. Given these flaws, the advantageous mechanism of myeloid haemopoiesis has not yet been uncovered in the current theories. The discoveries that bacterial components (lipopolysaccharide, LPS) and intestinal decontamination affect the mobilization of HSC trigger the interest in normal flora, which together with their components may have an effect on haemopoiesis. In the experiments in dogs and mice, researchers documented that the generation of myeloid cells has undergone changes in the bone marrow and periphery when antibiotics are used to regulate the normal intestinal flora and the concentration of its components. However, the same changes are not involved in lymphoid cells. Therefore, we hypothesize that in human body normal flora and its components are a driving force to maintain myeloid haemopoiesis under physiological conditions. To account for the selectiveness in haemopoiesis, these facts should be taken into consideration, such as HSC and mesenchymal stem cells (MSC) functionally expressed pattern recognition receptors (PRR), and both of them can self-migrate or be recruited by normal flora or its components into periphery. Dynamically monitoring the myeloid haemopoiesis may provide an important complementary program that precludes the abuse of antibiotics, which prevents diseases triggered by the imbalance of normal

  17. Evaluation of myeloid cells (tumor-associated tissue eosinophils and mast cells) infiltration in different grades of oral squamous cell carcinoma

    Science.gov (United States)

    Debta, Priyanka; Debta, Fakir Mohan; Chaudhary, Minal; Bussari, Smita

    2016-01-01

    Background: The multifunctional involvement and infiltration of myeloid cells (tumor-associated tissue eosinophils [TATE] and mast cells) can provide a unique opportunity to define relevant effectors functions that may represent novel, therapeutic options for modulation of tumor onset/growth. Aim: Our study aimed to evaluate infiltration of myeloid cells (TATE and Mast cells) infiltration in different grades (WHO grading) of oral squamous cell carcinoma (OSCC). Materials and Methods: Total 30 cases of OSCC were selected for this study. Hematoxylin and eosin stain and toluidine blue special stain, to evaluate TATE and the mast cells infiltration, were used. Three-year follow-up of OSCC cases was done. Result: Among 30 cases, 63.33% cases of OSCC showed TATE-positive and 36.66% cases showed TATE-negative. Regarding mast cells infiltration, 66.66% OSCC cases showed mast cells positive and 33.33% cases did not show significant mast cells infiltration. We found significant association of TATE and mast cells infiltration in OSCC cases. These myeloid cells infiltration significantly associated with age of patients but did not show any significant association with gender, site, and habit of cases. When we compared these cells infiltration with clinical stages and different histological grades of tumor, we found their infiltration is decreasing, from Stages 1 to Stage 3 of tumor and from well to poorly differentiated carcinoma. We have also found the less infiltration of these myeloid in recurrence cases of OSCC. Conclusion: As the infiltration of TATE and mast cells are correlated, along with evaluation of TATE, we should also evaluate the presence of mast cells infiltration in OSCC. The assessment of myeloid cells could become, in the future, useful for therapeutic approaches in this subset of the patient. PMID:27688609

  18. Myeloid cells in circulation and tumor microenvironment of breast cancer patients.

    Science.gov (United States)

    Toor, Salman M; Syed Khaja, Azharuddin Sajid; El Salhat, Haytham; Faour, Issam; Kanbar, Jihad; Quadri, Asif A; Albashir, Mohamed; Elkord, Eyad

    2017-06-01

    Pathological conditions including cancers lead to accumulation of a morphological mixture of highly immunosuppressive cells termed as myeloid-derived suppressor cells (MDSC). The lack of conclusive markers to identify human MDSC, due to their heterogeneous nature and close phenotypical and functional proximity with other cell subsets, made it challenging to identify these cells. Nevertheless, expansion of MDSC has been reported in periphery and tumor microenvironment of various cancers. The majority of studies on breast cancers were performed on murine models and hence limited literature is available on the relation of MDSC accumulation with clinical settings in breast cancer patients. The aim of this study was to investigate levels and phenotypes of myeloid cells in peripheral blood (n = 23) and tumor microenvironment of primary breast cancer patients (n = 7), compared with blood from healthy donors (n = 21) and paired non-tumor normal breast tissues from the same patients (n = 7). Using multicolor flow cytometric assays, we found that breast cancer patients had significantly higher levels of tumor-infiltrating myeloid cells, which comprised of granulocytes (P = 0.022) and immature cells that lack the expression of markers for fully differentiated monocytes or granulocytes (P = 0.016). Importantly, this expansion was not reflected in the peripheral blood. The immunosuppressive potential of these cells was confirmed by expression of Arginase 1 (ARG1), which is pivotal for T-cell suppression. These findings are important for developing therapeutic modalities to target mechanisms employed by immunosuppressive cells that generate an immune-permissive environment for the progression of cancer.

  19. Uncaria tomentosa stimulates the proliferation of myeloid progenitor cells.

    Science.gov (United States)

    Farias, Iria; do Carmo Araújo, Maria; Zimmermann, Estevan Sonego; Dalmora, Sergio Luiz; Benedetti, Aloisio Luiz; Alvarez-Silva, Marcio; Asbahr, Ana Carolina Cavazzin; Bertol, Gustavo; Farias, Júlia; Schetinger, Maria Rosa Chitolina

    2011-09-01

    The Asháninkas, indigenous people of Peru, use cat's claw (Uncaria tomentosa) to restore health. Uncaria tomentosa has antioxidant activity and works as an agent to repair DNA damage. It causes different effects on cell proliferation depending on the cell type involved; specifically, it can stimulate the proliferation of myeloid progenitors and cause apoptosis of neoplastic cells. Neutropenia is the most common collateral effect of chemotherapy. For patients undergoing cancer treatment, the administration of a drug that stimulates the proliferation of healthy hematopoietic tissue cells is very desirable. It is important to assess the acute effects of Uncaria tomentosa on granulocyte-macrophage colony-forming cells (CFU-GM) and in the recovery of neutrophils after chemotherapy-induced neutropenia, by establishing the correlation with filgrastim (rhG-CSF) treatment to evaluate its possible use in clinical oncology. The in vivo assay was performed in ifosfamide-treated mice receiving oral doses of 5 and 15 mg of Uncaria tomentosa and intraperitoneal doses of 3 and 9 μg of filgrastim, respectively, for four days. Colony-forming cell (CFC) assays were performed with human hematopoietic stem/precursor cells (hHSPCs) obtained from umbilical cord blood (UCB). Bioassays showed that treatment with Uncaria tomentosa significantly increased the neutrophil count, and a potency of 85.2% was calculated in relation to filgrastim at the corresponding doses tested. An in vitro CFC assay showed an increase in CFU-GM size and mixed colonies (CFU-GEMM) size at the final concentrations of 100 and 200 μg extract/mL. At the tested doses, Uncaria tomentosa had a positive effect on myeloid progenitor number and is promising for use with chemotherapy to minimize the adverse effects of this treatment. These results support the belief of the Asháninkas, who have classified Uncaria tomentosa as a 'powerful plant'. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  20. Cardiac function in survivors of childhood acute myeloid leukemia treated with chemotherapy only

    DEFF Research Database (Denmark)

    Jarfelt, Marianne; Andersen, Niels Holmark; Glosli, Heidi

    2015-01-01

    OBJECTIVES: We report cardiac function of patients treated for Childhood acute myeloid leukemia with chemotherapy only according to three consecutive Nordic protocols. METHODS: Ninety-eight of 138 eligible patients accepted examination with standardized echocardiography. Results were compared...

  1. Dopamine inhibits the function of Gr-1+CD115+ myeloid-derived suppressor cells through D1-like receptors and enhances anti-tumor immunity.

    Science.gov (United States)

    Wu, Jin; Zhang, Ruihua; Tang, Ning; Gong, Zizhen; Zhou, Jiefei; Chen, Yingwei; Chen, Kang; Cai, Wei

    2015-01-01

    MDSCs accumulate in tumor-bearing animals and cancer patients and are a major factor responsible for cancer-induced immunosuppression that limits effective cancer immunotherapy. Strategies aimed at effectively inhibiting the function of MDSCs are expected to enhance host anti-tumor immunity and improve cancer immunotherapy significantly. The neurotransmitter DA has been found to have anti-cancer activity, but the underlying mechanism is poorly understood. In this study, we sought to investigate the therapeutic mechanism and efficacy of DA on the inhibition of cancer development via the regulation of MDSC functions. The regulation of the suppressive function of Gr-1(+)CD115(+) MDSCs by DA was determined by use of murine syngeneic LLC and B16 graft models treated with DA in vivo, as well as Gr-1(+)CD115(+) MDSCs isolated from these model treated with DA ex vivo. Here, we show that Gr-1(+)CD115(+) monocytic MDSCs express D1-like DA receptors. DA dramatically attenuated the inhibitory function of tumor-induced monocytic MDSCs on T cell proliferation and IFN-γ production via D1-like DA receptors and retarded tumor growth. DA and other D1 receptor agonists inhibited IFN-γ-induced NO production by MDSCs from tumor-bearing mice and cancer patients. Decreased NO production was, in part, mediated via the suppression of p-ERK and p-JNK. In conclusion, the neurotransmitter DA potently inhibits the suppressive function of MDSC and enhances anti-tumor immunity. Our finding provides a mechanistic basis for the use of DA or D1-like receptor agonists to overcome tumor-induced immunosuppression in cancer immunotherapy. © Society for Leukocyte Biology.

  2. Myeloid derived suppressor cells (MDSCs are increased and exert immunosuppressive activity together with polymorphonuclear leukocytes (PMNs in chronic myeloid leukemia patients.

    Directory of Open Access Journals (Sweden)

    Cesarina Giallongo

    Full Text Available Tumor immune tolerance can derive from the recruitment of suppressor cell population, including myeloid derived suppressor cells (MDSCs, able to inhibit T cells activity. We identified a significantly expanded MDSCs population in chronic myeloid leukemia (CML patients at diagnosis that decreased to normal levels after imatinib therapy. In addition, expression of arginase 1 (Arg1 that depletes microenvironment of arginine, an essential aminoacid for T cell function, resulted in an increase in patients at diagnosis. Purified CML CD11b+CD33+CD14-HLADR- cells markedly suppressed normal donor T cell proliferation in vitro. Comparing CML Gr-MDSCs to autologous polymorphonuclear leukocytes (PMNs we observed a higher Arg1 expression and activity in PMNs, together with an inhibitory effect on T cells in vitro. Our data indicate that CML cells create an immuno-tolerant environment associated to MDSCs expansion with immunosuppressive capacity mediated by Arg1. In addition, we demonstrated for the first time also an immunosuppressive activity of CML PMNs, suggesting a strong potential immune escape mechanism created by CML cells, which control the anti-tumor reactive T cells. MDSCs should be monitored in imatinib discontinuation trials to understand their importance in relapsing patients.

  3. Recommendations for myeloid-derived suppressor cell nomenclature and characterization standards.

    Science.gov (United States)

    Bronte, Vincenzo; Brandau, Sven; Chen, Shu-Hsia; Colombo, Mario P; Frey, Alan B; Greten, Tim F; Mandruzzato, Susanna; Murray, Peter J; Ochoa, Augusto; Ostrand-Rosenberg, Suzanne; Rodriguez, Paulo C; Sica, Antonio; Umansky, Viktor; Vonderheide, Robert H; Gabrilovich, Dmitry I

    2016-07-06

    Myeloid-derived suppressor cells (MDSCs) have emerged as major regulators of immune responses in cancer and other pathological conditions. In recent years, ample evidence supports key contributions of MDSC to tumour progression through both immune-mediated mechanisms and those not directly associated with immune suppression. MDSC are the subject of intensive research with >500 papers published in 2015 alone. However, the phenotypic, morphological and functional heterogeneity of these cells generates confusion in investigation and analysis of their roles in inflammatory responses. The purpose of this communication is to suggest characterization standards in the burgeoning field of MDSC research.

  4. Oncogenic NRAS Primes Primary Acute Myeloid Leukemia Cells for Differentiation.

    Directory of Open Access Journals (Sweden)

    Cornelia Brendel

    Full Text Available RAS mutations are frequently found among acute myeloid leukemia patients (AML, generating a constitutively active signaling protein changing cellular proliferation, differentiation and apoptosis. We have previously shown that treatment of AML patients with high-dose cytarabine is preferentially beneficial for those harboring oncogenic RAS. On the basis of a murine AML cell culture model, we ascribed this effect to a RAS-driven, p53-dependent induction of differentiation. Hence, in this study we sought to confirm the correlation between RAS status and differentiation of primary blasts obtained from AML patients. The gene expression signature of AML blasts with oncogenic NRAS indeed corresponded to a more mature profile compared to blasts with wildtype RAS, as demonstrated by gene set enrichment analysis (GSEA and real-time PCR analysis of myeloid ecotropic viral integration site 1 homolog (MEIS1 in a unique cohort of AML patients. In addition, in vitro cell culture experiments with established cell lines and a second set of primary AML cells showed that oncogenic NRAS mutations predisposed cells to cytarabine (AraC driven differentiation. Taken together, our findings show that AML with inv(16 and NRAS mutation have a differentiation gene signature, supporting the notion that NRAS mutation may predispose leukemic cells to AraC induced differentiation. We therefore suggest that promotion of differentiation pathways by specific genetic alterations could explain the superior treatment outcome after therapy in some AML patient subgroups. Whether a differentiation gene expression status may generally predict for a superior treatment outcome in AML needs to be addressed in future studies.

  5. Binase induces apoptosis of transformed myeloid cells and does not induce T-cell immune response.

    Science.gov (United States)

    Ilinskaya, Olga N; Zelenikhin, Pavel V; Petrushanko, Irina Yu; Mitkevich, Vladimir A; Prassolov, Vladimir S; Makarov, Alexander A

    2007-10-01

    Microbial RNases along with such animal RNases as onconase and BS-RNase are a promising basis for developing new antitumor drugs. We have shown that the Bacillus intermedius RNase (binase) induces selective apoptosis of transformed myeloid cells. It attacks artificially expressing activated c-Kit myeloid progenitor FDC cells and chronic myelogenous leukemia cells K562. Binase did not induce apoptosis in leukocytes of healthy donors and in normal myeloid progenitor cells. The inability of binase to initiate expression of activation markers CD69 and IFN-gamma in CD4+ and CD8+ T-lymphocytes testifies that enzyme is devoid of superantigenic properties. Altogether, these results demonstrate that binase possesses therapeutic opportunities for treatment of genotyped human neoplasms expressing activated kit.

  6. Myeloid leukemia factor functions in anti-WSSV immune reaction of kuruma shrimp, Marsupenaeus japonicus.

    Science.gov (United States)

    Feng, Xiao-Wu; Huo, Li-Jie; Sun, Jie-Jie; Xu, Ji-Dong; Niu, Guo-Juan; Wang, Jin-Xing; Shi, Xiu-Zhen

    2017-09-12

    Myeloid leukemia factor (MLF) plays an important role in development, cell cycle, myeloid differentiation, and regulates the RUNX transcription factors. However, the function of MLF in immunity is still unclear. In this study, an MLF was identified and characterized in kuruma shrimp Marsupenaeus japonicus, and named as MjMLF. The full-length cDNA of MjMLF contained 1111 nucleotides, which had an opening reading frame of 816 bp encoding a protein of 272 amino acids with an MLF1-interacting protein domain. MjMLF could be ubiquitously detected in different tissues of shrimp at the transcriptional level. The expression pattern analysis showed that MjMLF could be upregulated in shrimp hemocytes and hepatopancreas after white spot syndrome virus challenge. The RNA interference and protein injection assay showed that MjMLF could inhibit WSSV replication in vivo. Flow cytometry assay showed that MjMLF could induce hemocytes apoptosis which functioned in the shrimp antiviral reaction. All the results suggested that MjMLF played an important role in the antiviral immune reaction of kuruma shrimp. The research indicated that MjMLF might function as a novel regulator to inhibit WSSV replication in shrimp. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Misfolded N-CoR is linked to the ectopic reactivation of CD34/Flt3-based stem-cell phenotype in promyelocytic and monocytic acute myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Dawn Sijin Nin

    2015-10-01

    Full Text Available Nuclear receptor co-repressor (N-CoR is the key component of generic co-repressor complex essential for the transcriptional control of genes involved in cellular hemostasis. We have recently reported that N-CoR actively represses Flt3, a key factor of hematopoietic stem cells (HSC self-renewal and growth; and that de-repression of Flt3 by the misfolded N-CoR plays important role in the pathogenesis of promyelocytic and monocytic acute myeloid leukemia (AML. The leukemic cells derived from the promyelocytic and monocytic AML are distinctly characterized by the ectopic reactivation of stem cell phenotypes in relatively committed myeloid compartment. However, the molecular mechanism underlying this phenomenon is not known. Here, we report that N-CoR function is essential for the commitment of primitive hematopoietic cells to the cells of myeloid lineage, and that loss of N-CoR function due to misfolding is linked to the ectopic reactivation of generic stem cell phenotypes in promyelocytic and monocytic AML. Analysis of N-CoR and Flt3 transcripts in mouse hematopoietic cells revealed a positive correlation between N-CoR level and the commitment of myeloid cells and an inverse correlation between N-CoR and Flt3 levels in primitive as well as committed myeloid cells. Enforced N-CoR expression in mouse HSCs inhibited their growth and self-renewal potentials and promoted maturation towards cells of myeloid lineage, suggesting a role of N-CoR in the commitment of cells of myeloid lineage. In contrast to AML cells with natively folded N-CoR, primary and secondary promyelocytic and monocytic AML cells harboring the misfolded N-CoR were highly positive for Flt3 and myeloid antigen based HSC marker CD34. Genetic and therapeutic restoration of N-CoR conformation significantly down-regulated the CD34 levels in monocytic AML cells, suggesting an important role of N-CoR in the suppression of CD34 based hematopoietic stem cell phenotypes. These finding

  8. IFN-γ differentially regulates subsets of Gr-1(+)CD11b(+) myeloid cells in chronic inflammation.

    Science.gov (United States)

    Zhan, Xiaoxia; Fang, Yimin; Hu, Shengfeng; Wu, Yongjian; Yang, Kun; Liao, Chunxin; Zhang, Yuanqing; Huang, Xi; Wu, Minhao

    2015-08-01

    During chronic inflammation, prolonged over-reactive immune response may lead to tissue destruction, while immune suppression hinders tissue repair and pathogen elimination. Therefore, precise regulation of the immune response is needed to avoid immuno-pathology. Interferon-gamma (IFN-γ) is widely used in clinical treatment of inflammatory diseases. However, the underlying mechanism remains unclear. Here, we evaluated the role of IFN-γ on CD11b(+)Gr-1(+) myeloid cell differentiation and function, using a heat-killed Mycobacterium bovis BCG-induced chronic inflammation model. After challenge with heat-killed BCG, two subpopulations of CD11b(+)Gr-1(+) myeloid cells were generated in the mouse spleen. Phenotypical, morphological and functional analysis indicated that the CD11b(+)Gr-1(high) Ly6G(high) Ly6C(low) subset was neutrophil-like myeloid-derived inducer cells (N-MDICs), which promoted T cell activation, while the other subset was CD11b(+)Gr-1(low) Ly6G(neg) Ly6C(high) monocyte-like myeloid-derived suppressor cells (M-MDSCs) that displayed extensive suppressor function. IFN-γ treatment dampened N-MDICs-mediated T cell activation through up-regulating T cell suppressive mediators, reactive oxygen species (ROS) and arginase I. While for M-MDSCs, IFN-γ reduced their suppressing activity by decreasing the arginase activity. Our study provides evidence that IFN-γ balances the over-reactive vs compromised immune response through different regulation of distinct myeloid subsets, and therefore displays significant therapeutic potential for effective immuno-therapy of chronic inflammatory diseases.

  9. The Hematopoietic Differentiation and Production of Mature Myeloid Cells from Human Pluripotent Stem Cells

    OpenAIRE

    Choi, Kyung-Dal; Vodyanik, Maxim; Slukvin, Igor I.

    2011-01-01

    Here we describe a protocol for hematopoietic differentiation of human pluripotent stem cells (hPSCs) and generation of mature myeloid cells from hPSCs through expansion and differentiation of hPSC-derived lin-CD34+CD43+CD45+ multipotent progenitors. The protocol is comprised of three major steps: (i) induction of hematopoietic differentiation by coculture of hPSCs with OP9 bone marrow stromal cells, (ii) short-term expansion of multipotent myeloid progenitors with a high dose of GM-CSF, and ...

  10. Canthin-6-one induces cell death, cell cycle arrest and differentiation in human myeloid leukemia cells.

    Science.gov (United States)

    Vieira Torquato, Heron F; Ribeiro-Filho, Antonio C; Buri, Marcus V; Araújo Júnior, Roberto T; Pimenta, Renata; de Oliveira, José Salvador R; Filho, Valdir C; Macho, Antonio; Paredes-Gamero, Edgar J; de Oliveira Martins, Domingos T

    2017-04-01

    Canthin-6-one is a natural product isolated from various plant genera and from fungi with potential antitumor activity. In the present study, we evaluate the antitumor effects of canthin-6-one in human myeloid leukemia lineages. Kasumi-1 lineage was used as a model for acute myeloid leukemia. Cells were treated with canthin-6-one and cell death, cell cycle and differentiation were evaluated in both total cells (Lin(+)) and leukemia stem cell population (CD34(+)CD38(-)Lin(-/low)). Among the human lineages tested, Kasumi-1 was the most sensitive to canthin-6-one. Canthin-6-one induced cell death with apoptotic (caspase activation, decrease of mitochondrial potential) and necrotic (lysosomal permeabilization, double labeling of annexin V/propidium iodide) characteristics. Moreover, canthin-6-one induced cell cycle arrest at G0/G1 (7μM) and G2 (45μM) evidenced by DNA content, BrdU incorporation and cyclin B1/histone 3 quantification. Canthin-6-one also promoted differentiation of Kasumi-1, evidenced by an increase in the expression of myeloid markers (CD11b and CD15) and the transcription factor PU.1. Furthermore, a reduction of the leukemic stem cell population and clonogenic capability of stem cells were observed. These results show that canthin-6-one can affect Kasumi-1 cells by promoting cell death, cell cycle arrest and cell differentiation depending on concentration used. Canthin-6-one presents an interesting cytotoxic activity against leukemic cells and represents a promising scaffold for the development of molecules for anti-leukemic applications, especially by its anti-leukemic stem cell activity. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. DACH1 regulates cell cycle progression of myeloid cells through the control of cyclin D, Cdk 4/6 and p21{sup Cip1}

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    Lee, Jae-Woong; Kim, Hyeng-Soo; Kim, Seonggon; Hwang, Junmo; Kim, Young Hun; Lim, Ga Young [School of Life Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Sohn, Wern-Joo [Department of Biochemistry, School of Dentistry, IHBR, Kyungpook National University, Daegu 700-412 (Korea, Republic of); Yoon, Suk-Ran [Cell Therapy Research Center, Korea Research Institute of Bioscience and Biotechnology, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Kim, Jae-Young [Department of Biochemistry, School of Dentistry, IHBR, Kyungpook National University, Daegu 700-412 (Korea, Republic of); Park, Tae Sung [Department of Laboratory Medicine, Kyung Hee University School of Medicine, 1 Hoegi-dong, Dongdaemun-gu, Seoul 130-702 (Korea, Republic of); Park, Kwon Moo [Department of Anatomy, Kyungpook National University School of Medicine, Daegu 700-422 (Korea, Republic of); Ryoo, Zae Young [School of Life Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Lee, Sanggyu, E-mail: slee@knu.ac.kr [School of Life Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer DACH1 increases cyclin D, F and Cdk 1, 4, 6 in mouse myeloid progenitor cells. Black-Right-Pointing-Pointer The knockdown of DACH1 blocked the cell cycle progression of HL-60 cells. Black-Right-Pointing-Pointer The novel effect of DACH1 related with cell cycle regulation and leukemogenesis. -- Abstract: The cell-fate determination factor Dachshund, a component of the Retinal Determination Gene Network (RDGN), has a role in breast tumor proliferation through the repression of cyclin D1 and several key regulators of embryonic stem cell function, such as Nanog and Sox2. However, little is known about the role of DACH1 in a myeloid lineage as a cell cycle regulator. Here, we identified the differential expression levels of extensive cell cycle regulators controlled by DACH1 in myeloid progenitor cells. The forced expression of DACH1 induced p27{sup Kip1} and repressed p21{sup Cip1}, which is a pivotal characteristic of the myeloid progenitor. Furthermore, DACH1 significantly increased the expression of cyclin D1, D3, F, and Cdk 1, 4, and 6 in myeloid progenitor cells. The knockdown of DACH1 blocked the cell cycle progression of HL-60 promyeloblastic cells through the decrease of cyclin D1, D3, F, and Cdk 1, 4, and 6 and increase in p21{sup Cip1}, which in turn decreased the phosphorylation of the Rb protein. The expression of Sox2, Oct4, and Klf4 was significantly up-regulated by the forced expression of DACH1 in mouse myeloid progenitor cells.

  12. Emerging roles of myeloid derived suppressor cells in hepatic inflammation and fibrosis

    Institute of Scientific and Technical Information of China (English)

    Linda; Hammerich; Frank; Tacke

    2015-01-01

    Myeloid derived suppressor cells(MDSC) are a heterogeneous population of immune cells that are potent suppressors of immune responses. MDSC emerge in various compartments in the body, such as blood, bonemarrow or spleen, especially in conditions of cancer, infections or inflammation. MDSC usually express CD11 b, CD33, and low levels of human leukocyte antigen-DR in humans or CD11 b and Gr1(Ly6C/G) in mice, and they can be further divided into granulocytic or monocytic MDSC. The liver is an important organ for MDSC induction and accumulation in hepatic as well as extrahepatic diseases. Different hepatic cells, especially hepatic stellate cells, as well as liver-derived soluble factors, including hepatocyte growth factor and acute phase proteins(SAA, KC), can promote the differentiation of MDSC from myeloid cells. Importantly, hepatic myeloid cells like neutrophils, monocytes and macrophages fulfill essential roles in acute and chronic liver diseases. Recent data from patients with liver diseases and animal models linked MDSC to the pathogenesis of hepatic inflammation, fibrosis and hepatocellular carcinoma(HCC). In settings of acute hepatitis, MDSC can limit immunogenic T cell responses and subsequent tissue injury. In patients with chronic hepatitis C, MDSC increase and may favor viral persistence. Animal models of chronic liver injury, however, have not yet conclusively clarified the involvement of MDSC for hepatic fibrosis. In human HCC and mouse models of liver cancer, MDSC are induced in the tumor environment and suppress anti-tumoral immune responses. Thus, the liver is a primary site of MDSC in vivo, and modulating MDSC functionality might represent a promising novel therapeutic target for liver diseases.

  13. Pseudomonas aeruginosa airway infection recruits and modulates neutrophilic myeloid-derived suppressor cells

    Directory of Open Access Journals (Sweden)

    Hasan Halit Öz

    2016-11-01

    Full Text Available Pseudomonas aeruginosa is an opportunistic pathogen that causes infections mainly in patients with cystic fibrosis (CF lung disease. Despite innate and adaptive immune responses upon infection, P. aeruginosa is capable of efficiently escaping host defenses, but the underlying immune mechanisms remain poorly understood. Myeloid-derived suppressor cells (MDSCs are innate immune cells that are functionally characterized by their potential to suppress T- and natural killer (NK-cell responses. Here we demonstrate, using an airway in vivo infection model, that P. aeruginosa recruits and activates neutrophilic MDSCs, which functionally suppress T-cell responses. We further show that the CF gene defect (cystic fibrosis transmembrane conductance regulator, CFTR modulates the functionality, but not the recruitment or generation of neutrophilic MDSCs. Collectively, we define a mechanism by which P. aeruginosa airway infection undermines host immunity by modulating neutrophilic MDSCs in vivo.

  14. Growth Arrest Specific 2 Is Up-Regulated in Chronic Myeloid Leukemia Cells and Required for Their Growth

    OpenAIRE

    Haixia Zhou; Yue Ge; Lili Sun; Wenjuan Ma; Jie Wu; Xiuyan Zhang; Xiaohui Hu; Eaves, Connie J; Depei Wu; Yun Zhao

    2014-01-01

    Although the generation of BCR-ABL is the molecular hallmark of chronic myeloid leukemia (CML), the comprehensive molecular mechanisms of the disease remain unclear yet. Growth arrest specific 2 (GAS2) regulates multiple cellular functions including cell cycle, apoptosis and calpain activities. In the present study, we found GAS2 was up-regulated in CML cells including CD34+ progenitor cells compared to their normal counterparts. We utilized RNAi and the expression of dominant negative form o...

  15. High-mobility group box protein 1 promotes the survival of myeloid-derived suppressor cells by inducing autophagy.

    Science.gov (United States)

    Parker, Katherine H; Horn, Lucas A; Ostrand-Rosenberg, Suzanne

    2016-09-01

    Myeloid-derived suppressor cells are immune-suppressive cells that are elevated in most individuals with cancer, where their accumulation and suppressive activity are driven by inflammation. As myeloid-derived suppressor cells inhibit anti-tumor immunity and promote tumor progression, we are determining how their viability is regulated. Previous studies have established that the damage-associated molecular pattern molecule high-mobility group box protein 1 drives myeloid-derived suppressor cell accumulation and suppressive potency and is ubiquitously present in the tumor microenvironment. As high-mobility group box protein 1 also facilitates tumor cell survival by inducing autophagy, we sought to determine if high-mobility group box protein 1 regulates myeloid-derived suppressor cell survival through induction of autophagy. Inhibition of autophagy increased the quantity of apoptotic myeloid-derived suppressor cells, demonstrating that autophagy extends the survival and increases the viability of myeloid-derived suppressor cells. Inhibition of high-mobility group box protein 1 similarly increased the level of apoptotic myeloid-derived suppressor cells and reduced myeloid-derived suppressor cell autophagy, demonstrating that in addition to inducing the accumulation of myeloid-derived suppressor cells, high-mobility group box protein 1 sustains myeloid-derived suppressor cell viability. Circulating myeloid-derived suppressor cells have a default autophagic phenotype, and tumor-infiltrating myeloid-derived suppressor cells are more autophagic, consistent with the concept that inflammatory and hypoxic conditions within the microenvironment of solid tumors contribute to tumor progression by enhancing immune-suppressive myeloid-derived suppressor cells. Overall, these results demonstrate that in addition to previously recognized protumor effects, high-mobility group box protein 1 contributes to tumor progression by increasing myeloid-derived suppressor cell viability by

  16. Over-Expression of Catalase in Myeloid Cells Confers Acute Protection Following Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    E. Bernadette Cabigas

    2014-05-01

    Full Text Available Cardiovascular disease is the leading cause of death in the United States and new treatment options are greatly needed. Oxidative stress is increased following myocardial infarction and levels of antioxidants decrease, causing imbalance that leads to dysfunction. Therapy involving catalase, the endogenous scavenger of hydrogen peroxide (H2O2, has been met with mixed results. When over-expressed in cardiomyocytes from birth, catalase improves function following injury. When expressed in the same cells in an inducible manner, catalase showed a time-dependent response with no acute benefit, but a chronic benefit due to altered remodeling. In myeloid cells, catalase over-expression reduced angiogenesis during hindlimb ischemia and prevented monocyte migration. In the present study, due to the large inflammatory response following infarction, we examined myeloid-specific catalase over-expression on post-infarct healing. We found a significant increase in catalase levels following infarction that led to a decrease in H2O2 levels, leading to improved acute function. This increase in function could be attributed to reduced infarct size and improved angiogenesis. Despite these initial improvements, there was no improvement in chronic function, likely due to increased fibrosis. These data combined with what has been previously shown underscore the need for temporal, cell-specific catalase delivery as a potential therapeutic option.

  17. A monoclonal antibody reactive with normal and leukemic human myeloid progenitor cells.

    Science.gov (United States)

    Griffin, J D; Linch, D; Sabbath, K; Larcom, P; Schlossman, S F

    1984-01-01

    Anti-MY9 is an IgG2b murine monoclonal antibody selected for reactivity with immature normal human myeloid cells. The MY9 antigen is expressed by blasts, promyelocytes and myelocytes in the bone marrow, and by monocytes in the peripheral blood. Erythrocytes, lymphocytes and platelets are MY9 negative. All myeloid colony-forming cells (CFU-GM), a fraction of erythroid burst-forming cells (BFU-E) and multipotent progenitors (CFU-GEMM) are MY9 positive. This antigen is further expressed by the leukemic cells of a majority of patients with AML and myeloid CML-BC. Leukemic stem cells (leukemic colony-forming cells, L-CFC) from most patients tested were also MY9 positive. In contrast, MY9 was not detected on lymphocytic leukemias. Anti-MY9 may be a valuable reagent for the purification of hematopoietic colony-forming cells and for the diagnosis of myeloid-lineage leukemias.

  18. Characterization of the murine myeloid precursor cell line MuMac-E8.

    Science.gov (United States)

    Fricke, Stephan; Pfefferkorn, Cathleen; Wolf, Doris; Riemschneider, Sina; Kohlschmidt, Janine; Hilger, Nadja; Fueldner, Christiane; Knauer, Jens; Sack, Ulrich; Emmrich, Frank; Lehmann, Jörg

    2014-01-01

    Starting point for the present work was the assumption that the cell line MuMac-E8 represents a murine cell population with stem cell properties. Preliminary studies already pointed to the expression of stem-cell associated markers and a self-regenerative potential of the cells. The cell line MuMac-E8 should be examined for their differential stage within stem cell hierarchy. MuMac-E8 cells were derived from a chimeric mouse model of arthritis. It could be shown that MuMac-E8 cells express mRNA of some genes associated with pluripotent stem cells (Nanog, Nucleostemin), of genes for hematopoietic markers (EPCR, Sca-1, CD11b, CD45), for the mesenchymal marker CD105 and of genes for the neural markers Pax-6 and Ezrin. In methylcellulose and May-Grünwald-Giemsa staining, hematopoietic colonies were obtained but the hematopoietic system of lethally irradiated mice could not be rescued. Osteogenic differentiation was not detectable. Thus, it became evident that MuMac-E8 represents not a stem cell line. However, MuMac-E8 cells expressed several myeloid surface markers (i.e. CD11b, F4/80, CD14, CD64), showed phagocytosis and is capable of producing nitric oxide. Thus, this cell line seems to be arrested an advanced stage of myeloid differentiation. Adherence data measured by impedance-based real-time cell analysis together with cell morphology data suggested that MuMac-E8 represents a new macrophage precursor cell line exhibiting weak adherence. This cell line is suitable as an in-vitro model for testing of macrophage functions. Moreover, it might be also useful for differentiation or reprogramming studies.

  19. Characterization of the murine myeloid precursor cell line MuMac-E8.

    Directory of Open Access Journals (Sweden)

    Stephan Fricke

    Full Text Available Starting point for the present work was the assumption that the cell line MuMac-E8 represents a murine cell population with stem cell properties. Preliminary studies already pointed to the expression of stem-cell associated markers and a self-regenerative potential of the cells. The cell line MuMac-E8 should be examined for their differential stage within stem cell hierarchy. MuMac-E8 cells were derived from a chimeric mouse model of arthritis. It could be shown that MuMac-E8 cells express mRNA of some genes associated with pluripotent stem cells (Nanog, Nucleostemin, of genes for hematopoietic markers (EPCR, Sca-1, CD11b, CD45, for the mesenchymal marker CD105 and of genes for the neural markers Pax-6 and Ezrin. In methylcellulose and May-Grünwald-Giemsa staining, hematopoietic colonies were obtained but the hematopoietic system of lethally irradiated mice could not be rescued. Osteogenic differentiation was not detectable. Thus, it became evident that MuMac-E8 represents not a stem cell line. However, MuMac-E8 cells expressed several myeloid surface markers (i.e. CD11b, F4/80, CD14, CD64, showed phagocytosis and is capable of producing nitric oxide. Thus, this cell line seems to be arrested an advanced stage of myeloid differentiation. Adherence data measured by impedance-based real-time cell analysis together with cell morphology data suggested that MuMac-E8 represents a new macrophage precursor cell line exhibiting weak adherence. This cell line is suitable as an in-vitro model for testing of macrophage functions. Moreover, it might be also useful for differentiation or reprogramming studies.

  20. Haemophilus ducreyi partially activates human myeloid dendritic cells.

    Science.gov (United States)

    Banks, Keith E; Humphreys, Tricia L; Li, Wei; Katz, Barry P; Wilkes, David S; Spinola, Stanley M

    2007-12-01

    Dendritic cells (DC) orchestrate innate and adaptive immune responses to bacteria. How Haemophilus ducreyi, which causes genital ulcers and regional lymphadenitis, interacts with DC is unknown. H. ducreyi evades uptake by polymorphonuclear leukocyte and macrophage-like cell lines by secreting LspA1 and LspA2. Many H. ducreyi strains express cytolethal distending toxin (CDT), and recombinant CDT causes apoptosis of DC in vitro. Here, we examined interactions between DC and H. ducreyi 35000HP, which produces LspA1, LspA2, and CDT. In human volunteers infected with 35000HP, the ratio of myeloid DC to plasmacytoid DC was 2.8:1 in lesions, compared to a ratio of 1:1 in peripheral blood. Using myeloid DC derived from monocytes as surrogates for lesional DC, we found that DC infected with 35000HP remained as viable as uninfected DC for up to 48 h. Gentamicin protection and confocal microscopy assays demonstrated that DC ingested and killed 35000HP, but killing was incomplete at 48 h. The expression of LspA1 and LspA2 did not inhibit the uptake of H. ducreyi, despite inactivating Src kinases. Infection of DC with live 35000HP caused less cell surface marker activation than infection with heat-killed 35000HP and lipopolysaccharide (LPS) and inhibited maturation by LPS. However, infection of DC with live bacteria caused the secretion of significantly higher levels of interleukin-6 and tumor necrosis factor alpha than infection with heat-killed bacteria and LPS. The survival of H. ducreyi in DC may provide a mechanism by which the organism traffics to lymph nodes. Partial activation of DC may abrogate the establishment of a full Th1 response and an environment that promotes phagocytosis.

  1. Myeloid derived suppressor cells enhance IgE-mediated mast cell responses

    Science.gov (United States)

    We previously demonstrated that enhanced development of myeloid derived suppressor cells (MDSC) in ADAM10 transgenic mice yielded resistance to infection with Nippostrongylus brasiliensis infection, and that co-culturing MDSC with IgE-activated mast cells enhanced cytokine production. In the current...

  2. Potential role of curcumin and taurine combination therapy on human myeloid leukemic cells propagated in vitro.

    Science.gov (United States)

    El-Houseini, Motawa E; Refaei, Mohammed Osman; Amin, Ahmed Ibrahim; Abol-Ftouh, Mahmoud A

    2013-10-01

    Curcumin and taurine are natural products that have been used in this study evaluating their therapeutic effect on myeloid leukemic cells propagated in vitro. Sixty patients with myeloid leukemia and 30 healthy volunteers were enrolled in the study. All patient groups were admitted to the Medical Oncology Department of the National Cancer Institute, Cairo University. There were statistically significant differences between treated leukemic cells compared to normal mononuclear leukocytes in cell density, interferon-γ and immunophenotypic profile, mainly CD4+, CD8 + and CD25+. This work highlights the possibility of using curcumin and taurine as a potential useful therapy in the management of patients suffering from chronic and acute myeloid leukemias.

  3. β-Catenin-regulated myeloid cell adhesion and migration determine wound healing.

    Science.gov (United States)

    Amini-Nik, Saeid; Cambridge, Elizabeth; Yu, Winston; Guo, Anne; Whetstone, Heather; Nadesan, Puviindran; Poon, Raymond; Hinz, Boris; Alman, Benjamin A

    2014-06-01

    A β-catenin/T cell factor-dependent transcriptional program is critical during cutaneous wound repair for the regulation of scar size; however, the relative contribution of β-catenin activity and function in specific cell types in the granulation tissue during the healing process is unknown. Here, cell lineage tracing revealed that cells in which β-catenin is transcriptionally active express a gene profile that is characteristic of the myeloid lineage. Mice harboring a macrophage-specific deletion of the gene encoding β-catenin exhibited insufficient skin wound healing due to macrophage-specific defects in migration, adhesion to fibroblasts, and ability to produce TGF-β1. In irradiated mice, only macrophages expressing β-catenin were able to rescue wound-healing deficiency. Evaluation of scar tissue collected from patients with hypertrophic and normal scars revealed a correlation between the number of macrophages within the wound, β-catenin levels, and cellularity. Our data indicate that β-catenin regulates myeloid cell motility and adhesion and that β-catenin-mediated macrophage motility contributes to the number of mesenchymal cells and ultimate scar size following cutaneous injury.

  4. Myeloid and T Cell-Derived TNF Protects against Central Nervous System Tuberculosis

    Science.gov (United States)

    Hsu, Nai-Jen; Francisco, Ngiambudulu M.; Keeton, Roanne; Allie, Nasiema; Quesniaux, Valérie F. J.; Ryffel, Bernhard; Jacobs, Muazzam

    2017-01-01

    Tuberculosis of the central nervous system (CNS-TB) is a devastating complication of tuberculosis, and tumor necrosis factor (TNF) is crucial for innate immunity and controlling the infection. TNF is produced by many cell types upon activation, in particularly the myeloid and T cells during neuroinflammation. Here we used mice with TNF ablation targeted to myeloid and T cell (MT-TNF−/−) to assess the contribution of myeloid and T cell-derived TNF in immune responses during CNS-TB. These mice exhibited impaired innate immunity and high susceptibility to cerebral Mycobacterium tuberculosis infection, a similar phenotype to complete TNF-deficient mice. Further, MT-TNF−/− mice were not able to control T cell responses and cytokine/chemokine production. Thus, our data suggested that collective TNF production by both myeloid and T cells are required to provide overall protective immunity against CNS-TB infection. PMID:28280495

  5. Natural killer cells require monocytic Gr-1(+)/CD11b(+) myeloid cells to eradicate orthotopically engrafted glioma cells.

    Science.gov (United States)

    Baker, Gregory J; Chockley, Peter; Zamler, Daniel; Castro, Maria G; Lowenstein, Pedro R

    2016-06-01

    Malignant gliomas are resistant to natural killer (NK) cell immune surveillance. However, the mechanisms used by these cancers to suppress antitumor NK cell activity remain poorly understood. We have recently reported on a novel mechanism of innate immune evasion characterized by the overexpression of the carbohydrate-binding protein galectin-1 by both mouse and rat malignant glioma. Here, we investigate the cytokine profile of galectin-1-deficient GL26 cells and describe the process by which these tumors are targeted by the early innate immune system in RAG1(-/-) and C57BL/6J mice. Our data reveal that galectin-1 knockdown in GL26 cells heightens their inflammatory status leading to the rapid recruitment of Gr-1(+)/CD11b(+) myeloid cells and NK1.1(+) NK cells into the brain tumor microenvironment, culminating in tumor clearance. We show that immunodepletion of Gr-1(+) myeloid cells in RAG1(-/-) mice permits the growth of galectin-1-deficient glioma despite the presence of NK cells, thus demonstrating an essential role for myeloid cells in the clearance of galectin-1-deficient glioma. Further characterization of tumor-infiltrating Gr-1(+)/CD11b(+) cells reveals that these cells also express CCR2 and Ly-6C, markers consistent with inflammatory monocytes. Our results demonstrate that Gr-1(+)/CD11b(+) myeloid cells, often referred to as myeloid-derived suppressor cells (MDSCs), are required for antitumor NK cell activity against galectin-1-deficient GL26 glioma. We conclude that glioma-derived galectin-1 represents an important factor in dictating the phenotypic behavior of monocytic Gr-1(+)/CD11b(+) myeloid cells. Galectin-1 suppression may be a valuable treatment approach for clinical glioma by promoting their innate immune-mediated recognition and clearance through the concerted effort of innate myeloid and lymphoid cell lineages.

  6. Hedgehog signalling in myeloid cells impacts on body weight, adipose tissue inflammation and glucose metabolism.

    Science.gov (United States)

    Braune, Julia; Weyer, Ulrike; Matz-Soja, Madlen; Hobusch, Constance; Kern, Matthias; Kunath, Anne; Klöting, Nora; Kralisch, Susann; Blüher, Matthias; Gebhardt, Rolf; Zavros, Yana; Bechmann, Ingo; Gericke, Martin

    2017-05-01

    Recently, hedgehog (Hh) was identified as a crucial player in adipose tissue development and energy expenditure. Therefore, we tested whether Hh ligands are regulated in obesity. Further, we aimed at identifying potential target cells of Hh signalling and studied the functional impact of Hh signalling on adipose tissue inflammation and glucose metabolism. Hh ligands and receptors were analysed in adipose tissue or serum from lean and obese mice as well as in humans. To study the impact on adipose tissue inflammation and glucose metabolism, Hh signalling was specifically blocked in myeloid cells using a conditional knockout approach (Lys-Smo (-/-)). Desert Hh (DHH) and Indian Hh (IHH) are local Hh ligands, whereas Sonic Hh is not expressed in adipose tissue from mice or humans. In mice, obesity leads to a preferential upregulation of Hh ligands (Dhh) and signalling components (Ptch1, Smo and Gli1) in subcutaneous adipose tissue. Further, adipose tissue macrophages are Hh target cells owing to the expression of Hh receptors, such as Patched1 and 2. Conditional knockout of Smo (which encodes Smoothened, a mandatory Hh signalling component) in myeloid cells increases body weight and adipose tissue inflammation and attenuates glucose tolerance, suggesting an anti-inflammatory effect of Hh signalling. In humans, adipose tissue expression of DHH and serum IHH decrease with obesity and type 2 diabetes, which might be explained by the intake of metformin. Interestingly, metformin reduced Dhh and Ihh expression in mouse adipose tissue explants. Hh signalling in myeloid cells affects adipose tissue inflammation and glucose metabolism and may be a potential target to treat type 2 diabetes.

  7. Gr1(intCD11b+ myeloid-derived suppressor cells in Mycobacterium tuberculosis infection.

    Directory of Open Access Journals (Sweden)

    Andrés Obregón-Henao

    Full Text Available BACKGROUND: Tuberculosis is one of the world's leading killers, stealing 1.4 million lives and causing 8.7 million new and relapsed infections in 2011. The only vaccine against tuberculosis is BCG which demonstrates variable efficacy in adults worldwide. Human infection with Mycobacterium tuberculosis results in the influx of inflammatory cells to the lung in an attempt to wall off bacilli by forming a granuloma. Gr1(intCD11b(+ cells are called myeloid-derived suppressor cells (MDSC and play a major role in regulation of inflammation in many pathological conditions. Although MDSC have been described primarily in cancer their function in tuberculosis remains unknown. During M. tuberculosis infection it is crucial to understand the function of cells involved in the regulation of inflammation during granuloma formation. Understanding their relative impact on the bacilli and other cellular phenotypes is necessary for future vaccine and drug design. METHODOLOGY/PRINCIPAL FINDINGS: We compared the bacterial burden, lung pathology and Gr1(intCD11b(+ myeloid-derived suppressor cell immune responses in M. tuberculosis infected NOS2-/-, RAG-/-, C3HeB/FeJ and C57/BL6 mice. Gr-1(+ cells could be found on the edges of necrotic lung lesions in NOS2-/-, RAG-/-, and C3HeB/FeJ, but were absent in wild-type mice. Both populations of Gr1(+CD11b(+ cells expressed high levels of arginase-1, and IL-17, additional markers of myeloid derived suppressor cells. We then sorted the Gr1(hi and Gr1(int populations from M. tuberculosis infected NOS-/- mice and placed the sorted both Gr1(int populations at different ratios with naïve or M. tuberculosis infected splenocytes and evaluated their ability to induce activation and proliferation of CD4+T cells. Our results showed that both Gr1(hi and Gr1(int cells were able to induce activation and proliferation of CD4+ T cells. However this response was reduced as the ratio of CD4(+ T to Gr1(+ cells increased. Our results

  8. Gr1intCD11b+ Myeloid-Derived Suppressor Cells in Mycobacterium tuberculosis Infection

    Science.gov (United States)

    Obregón-Henao, Andrés; Henao-Tamayo, Marcela; Orme, Ian M.; Ordway, Diane J.

    2013-01-01

    Background Tuberculosis is one of the world’s leading killers, stealing 1.4 million lives and causing 8.7 million new and relapsed infections in 2011. The only vaccine against tuberculosis is BCG which demonstrates variable efficacy in adults worldwide. Human infection with Mycobacterium tuberculosis results in the influx of inflammatory cells to the lung in an attempt to wall off bacilli by forming a granuloma. Gr1intCD11b+ cells are called myeloid-derived suppressor cells (MDSC) and play a major role in regulation of inflammation in many pathological conditions. Although MDSC have been described primarily in cancer their function in tuberculosis remains unknown. During M. tuberculosis infection it is crucial to understand the function of cells involved in the regulation of inflammation during granuloma formation. Understanding their relative impact on the bacilli and other cellular phenotypes is necessary for future vaccine and drug design. Methodology/Principal Findings We compared the bacterial burden, lung pathology and Gr1intCD11b+ myeloid-derived suppressor cell immune responses in M. tuberculosis infected NOS2-/-, RAG-/-, C3HeB/FeJ and C57/BL6 mice. Gr-1+ cells could be found on the edges of necrotic lung lesions in NOS2-/-, RAG-/-, and C3HeB/FeJ, but were absent in wild-type mice. Both populations of Gr1+CD11b+ cells expressed high levels of arginase-1, and IL-17, additional markers of myeloid derived suppressor cells. We then sorted the Gr1hi and Gr1int populations from M. tuberculosis infected NOS-/- mice and placed the sorted both Gr1int populations at different ratios with naïve or M. tuberculosis infected splenocytes and evaluated their ability to induce activation and proliferation of CD4+T cells. Our results showed that both Gr1hi and Gr1int cells were able to induce activation and proliferation of CD4+ T cells. However this response was reduced as the ratio of CD4+ T to Gr1+ cells increased. Our results illustrate a yet unrecognized interplay

  9. Rare myeloid sarcoma/acute myeloid leukemia with adrenal mass after allogeneic mobilization peripheral blood stem cell transplantation

    Institute of Scientific and Technical Information of China (English)

    Ya-Fei Wang; Qian Li; Wen-Gui Xu; Jian-Yu Xiao; Qing-Song Pang; Qing Yang; Yi-Zuo Zhang

    2013-01-01

    Myeloid sarcoma (MS) is a rare hematological neoplasm that develops either de novo or concurrently with acute myeloid leukemia (AML). This neoplasm can also be an initial manifestation of relapse in a previously treated AML that is in remission. A 44-year-old male patient was diagnosed with testis MS in a local hospital in August 2010. Atfer one month, bone marrow biopsy and aspiration conifrmed the diagnosis of AML. Allogeneic mobilization peripheral blood stem cell transplantation was performed, with the sister of the patient as donor, after complete remission (CR) was achieved by chemotherapy. Five months after treatment, an adrenal mass was detected by positron emission tomography-computed tomography (PET-CT). Radiotherapy was performed for the localized mass after a multidisciplinary team (MDT) discussion. hTe patient is still alive as of May 2013, with no evidence of recurrent MS or leukemia.

  10. Retinoic acid induction of CD38 antigen expression on normal and leukemic human myeloid cells: relationship with cell differentiation.

    Science.gov (United States)

    Prus, Eugenia; Fibach, Eitan

    2003-04-01

    Differentiation in the hematopoietic system involves, among other changes, altered expression of antigens, including the CD34 and CD38 surface antigens. In normal hematopoiesis, the most immature stem cells have the CD34 + CD34 - phenotype. In acute myeloid leukemia (AML), although blasts from most patients are CD38 +, some are CD38 - . AML blasts are blocked at early stages of differentiation; in some leukemic cells this block can be overcome by a variety of agents, including retinoids, that induce maturation into macrophages and granulocytes both in vitro and in vivo. Retinoids can also induce CD38 expression. In the present study, we investigated the relationship between induction of CD38 expression and induction of myeloid differentiation by retinoic acid (RA) in normal and leukemic human hematopoietic cells. In the promyelocytic (PML) CD34 - cell lines, HL60 and CB-1, as well as in normal CD34 + CD34 - hematopietic progenitor cells RA induced both CD38 expression as well as morphological and functional myeloid differentiation that resulted in loss of self-renewal. In contrast, in the myeloblastic CD34 + leukemic cell lines, ML-1 and KG-1a, as well as in primary cultures of cells derived from CD34 + -AML (M0 and M1) patients, RA caused an increase in CD38 + that was not associated with significant differentiation. Yet, long exposure of ML-1, but not KG-1, cells to RA resulted in loss of self-renewal. The results suggest that while in normal hematopoietic cells and in PML CD34 - cells induction of CD38 antigen expression by RA results in terminal differentiation along the myeloid lineage, in early myeloblastic leukemic CD34 + cells, induction of CD38 and differentiation are not functionally related. Since, several lines of evidence suggest that the CD38 - cells are the targets of leukemic transformation, transition of these cellsinto CD38 + phenotype by RA or other drugs may have therapeutic effect, either alone or in conjunction with cytotoxic drugs, regardless

  11. Tumor-derived IL-35 promotes tumor growth by enhancing myeloid cell accumulation and angiogenesis.

    Science.gov (United States)

    Wang, Zhihui; Liu, Jin-Qing; Liu, Zhenzhen; Shen, Rulong; Zhang, Guoqiang; Xu, Jianping; Basu, Sujit; Feng, Youmei; Bai, Xue-Feng

    2013-03-01

    IL-35 is a member of the IL-12 family of cytokines that is comprised of an IL-12 p35 subunit and an IL-12 p40-related protein subunit, EBV-induced gene 3 (EBI3). IL-35 functions through IL-35R and has a potent immune-suppressive activity. Although IL-35 was demonstrated to be produced by regulatory T cells, gene-expression analysis revealed that it is likely to have a wider distribution, including expression in cancer cells. In this study, we demonstrated that IL-35 is produced in human cancer tissues, such as large B cell lymphoma, nasopharyngeal carcinoma, and melanoma. To determine the roles of tumor-derived IL-35 in tumorigenesis and tumor immunity, we generated IL-35-producing plasmacytoma J558 and B16 melanoma cells and observed that the expression of IL-35 in cancer cells does not affect their growth and survival in vitro, but it stimulates tumorigenesis in both immune-competent and Rag1/2-deficient mice. Tumor-derived IL-35 increases CD11b(+)Gr1(+) myeloid cell accumulation in the tumor microenvironment and, thereby, promotes tumor angiogenesis. In immune-competent mice, spontaneous CTL responses to tumors are diminished. IL-35 does not directly inhibit tumor Ag-specific CD8(+) T cell activation, differentiation, and effector functions. However, IL-35-treated cancer cells had increased expression of gp130 and reduced sensitivity to CTL destruction. Thus, our study indicates novel functions for IL-35 in promoting tumor growth via the enhancement of myeloid cell accumulation, tumor angiogenesis, and suppression of tumor immunity.

  12. Hematopoietic Cell Transplantation Outcomes in Monosomal Karyotype Myeloid Malignancies.

    Science.gov (United States)

    Pasquini, Marcelo C; Zhang, Mei-Jie; Medeiros, Bruno C; Armand, Philippe; Hu, Zhen-Huan; Nishihori, Taiga; Aljurf, Mahmoud D; Akpek, Görgün; Cahn, Jean-Yves; Cairo, Mitchell S; Cerny, Jan; Copelan, Edward A; Deol, Abhinav; Freytes, César O; Gale, Robert Peter; Ganguly, Siddhartha; George, Biju; Gupta, Vikas; Hale, Gregory A; Kamble, Rammurti T; Klumpp, Thomas R; Lazarus, Hillard M; Luger, Selina M; Liesveld, Jane L; Litzow, Mark R; Marks, David I; Martino, Rodrigo; Norkin, Maxim; Olsson, Richard F; Oran, Betul; Pawarode, Attaphol; Pulsipher, Michael A; Ramanathan, Muthalagu; Reshef, Ran; Saad, Ayman A; Saber, Wael; Savani, Bipin N; Schouten, Harry C; Ringdén, Olle; Tallman, Martin S; Uy, Geoffrey L; Wood, William A; Wirk, Baldeep; Pérez, Waleska S; Batiwalla, Minoo; Weisdorf, Daniel J

    2016-02-01

    The presence of monosomal karyotype (MK+) in acute myeloid leukemia (AML) is associated with dismal outcomes. We evaluated the impact of MK+ in AML (MK+AML, n = 240) and in myelodysplastic syndrome (MDS) (MK+MDS, n = 221) on hematopoietic cell transplantation outcomes compared with other cytogenetically defined groups (AML, n = 3360; MDS, n = 1373) as reported to the Center for International Blood and Marrow Transplant Research from 1998 to 2011. MK+ AML was associated with higher disease relapse (hazard ratio, 1.98; P < .01), similar transplantation-related mortality (TRM) (hazard ratio, 1.01; P = .90), and worse survival (hazard ratio, 1.67; P < .01) compared with those outcomes for other cytogenetically defined AML. Among patients with MDS, MK+ MDS was associated with higher disease relapse (hazard ratio, 2.39; P < .01), higher TRM (hazard ratio, 1.80; P < .01), and worse survival (HR, 2.02; P < .01). Subset analyses comparing chromosome 7 abnormalities (del7/7q) with or without MK+ demonstrated higher mortality for MK+ disease in for both AML (hazard ratio, 1.72; P < .01) and MDS (hazard ratio, 1.79; P < .01). The strong negative impact of MK+ in myeloid malignancies was observed in all age groups and using either myeloablative or reduced-intensity conditioning regimens. Alternative approaches to mitigate disease relapse in this population are needed. Copyright © 2016 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  13. Modulatory Effects and Action Mechanisms of Tryptanthrin on Murine Myeloid Leukemia Cells

    Institute of Scientific and Technical Information of China (English)

    Hoi-Ling Chan; Hon-Yan Yip; Nai-Ki Mak; Kwok-Nam Leung

    2009-01-01

    Leukemia is the disorder of hematopoietic cell development and is characterized by an uncoupling of cell proliferation and differentiation. There is a pressing need for the development of novel tactics for leukemia therapy as conventional treatments often have severe adverse side effects. Tryptanthrin (6,12-dihydro-6,12-dioxoindolo-(2,1-b)-quinazoline) is a naturally-occurring, weakly basic alkaloid isolated from the dried roots of medicinal indigo plants (Ban-Lan-Gen). It has been reported to have various biological and pharmacological activities, including anti-microbial, anti-inflammatory, immunomodulatory and anti-tumor effects. However, its modulatory effects and action mechanisms on myeloid cells remain poorly understood. In this study, tryptanthrin was shown to suppress the proliferation of the murine myeloid leukemia WEHI-3B JCS cells in a dose- and time-dependent manner. It also significantly reduced the growth of WEHI-3B JCS cells in vivo in syngeneic BALB/c mice. However, it exhibited no significant direct cytotoxicity on normal murine peritoneal macrophages. Flow cytometric analysis showed an obvious cell cycle arrest of the tryptanthrin-treated WEHI-3B JCS cells at the G0/G1 phase. The expression of cyclin D2,D3, Cdk 2, 4 and 6 genes in WEHI-3B JCS cells was found to be down-regulated at 24 h as measured by RT-PCR. Morphological and functional studies revealed that tryptanthrin could induce differentiation in WEHI-3B JCS cells, as shown by the increases in vacuolation, cellular granularity and NBT-reducing activity in tryptanthrin-treated cells. Collectively, our findings suggest that tryptanthrin might exert its anti-tumor effect on the murine myelomonocytic leukemia WEHI-3B JCS cells by causing cell cycle arrest and by triggering cell differentiation. Cellular & Molecular Immunology. 2009;6(5):335-342.

  14. Novel combination treatments targeting chronic myeloid leukemia stem cells.

    Science.gov (United States)

    Al Baghdadi, Tareq; Abonour, Rafat; Boswell, H Scott

    2012-04-01

    Chronic myeloid leukemia (CML) is currently considered incurable in most patients. Stem cell transplantation, an accepted curative option for which extensive experience has been gained, is limited by high morbidity and mortality rates, particularly in older patients. Tyrosine kinase inhibitors targeting BCR-ABL are widely used and induce remission in a high proportion of patients, but resistance and incomplete response to these agents portends eventual relapse and disease progression. Although BCR-ABL inhibitors eradicate most CML cells, they are largely ineffective against the reservoir of quiescent leukemic stem cells (LSCs). Thus a strong medical need exists for therapies that effectively eradicate LSCs and is currently a focus of extensive research. To date, evidence obtained from in vitro studies, animal models, and clinical CML specimens suggests that an effective approach may be to partner existing BCR-ABL inhibitors with compounds targeting key stem cell molecular effectors, including Wnt/β-catenin, hedgehog pathway components, histone deacetylase (HDAC), transforming growth factor-β (TGF-β), Janus kinase 2, promyelocytic leukemia protein, and arachidonate 5-lipoxygenase (ALOX5). Novel combinations may sensitize LSCs to BCR-ABL inhibitors, thereby overcoming resistance and creating the possibility of improving disease outcome beyond the current standard of care. Copyright © 2012. Published by Elsevier Inc.

  15. Regulatory T cells and human myeloid dendritic cells promote tolerance via programmed death ligand-1.

    Directory of Open Access Journals (Sweden)

    Shoba Amarnath

    2010-02-01

    Full Text Available Immunotherapy using regulatory T cells (Treg has been proposed, yet cellular and molecular mechanisms of human Tregs remain incompletely characterized. Here, we demonstrate that human Tregs promote the generation of myeloid dendritic cells (DC with reduced capacity to stimulate effector T cell responses. In a model of xenogeneic graft-versus-host disease (GVHD, allogeneic human DC conditioned with Tregs suppressed human T cell activation and completely abrogated posttransplant lethality. Tregs induced programmed death ligand-1 (PD-L1 expression on Treg-conditioned DC; subsequently, Treg-conditioned DC induced PD-L1 expression in vivo on effector T cells. PD-L1 blockade reversed Treg-conditioned DC function in vitro and in vivo, thereby demonstrating that human Tregs can promote immune suppression via DC modulation through PD-L1 up-regulation. This identification of a human Treg downstream cellular effector (DC and molecular mechanism (PD-L1 will facilitate the rational design of clinical trials to modulate alloreactivity.

  16. A novel mouse model of conditional IRAK-M deficiency in myeloid cells: application in lung Pseudomonas aeruginosa infection.

    Science.gov (United States)

    Jiang, Di; Matsuda, Jennifer; Berman, Reena; Schaefer, Niccolette; Stevenson, Connor; Gross, James; Zhang, Bicheng; Sanchez, Amelia; Li, Liwu; Chu, Hong Wei

    2017-02-01

    Myeloid cells such as macrophages are critical to innate defense against infection. IL-1 receptor-associated kinase M (IRAK-M) is a negative regulator of TLR signaling during bacterial infection, but the role of myeloid cell IRAK-M in bacterial infection is unclear. Our goal was to generate a novel conditional knockout mouse model to define the role of myeloid cell IRAK-M during bacterial infection. Myeloid cell-specific IRAK-M knockout mice were generated by crossing IRAK-M floxed mice with LysM-Cre knock-in mice. The resulting LysM-Cre(+)/IRAK-M(fl/wt) and control (LysM-Cre(-)/IRAK-M(fl/wt)) mice were intranasally infected with Pseudomonas aeruginosa (PA). IRAK-M deletion, inflammation, myeloperoxidase (MPO) activity and PA load were measured in leukocytes, bronchoalveolar lavage (BAL) fluid and lungs. PA killing assay with BAL fluid was performed to determine mechanisms of IRAK-M-mediated host defense. IRAK-M mRNA and protein levels in alveolar and lung macrophages were significantly reduced in LysM-Cre(+)/IRAK-M(fl/wt) mice compared with control mice. Following PA infection, LysM-Cre(+)/IRAK-M(fl/wt) mice have enhanced lung neutrophilic inflammation, including MPO activity, but reduced PA load. The increased lung MPO activity in LysM-Cre(+)/IRAK-M(fl/wt) mouse BAL fluid reduced PA load. Generation of IRAK-M conditional knockout mice will enable investigators to determine precisely the function of IRAK-M in myeloid cells and other types of cells during infection and inflammation.

  17. Myeloid Cells and Related Chronic Inflammatory Factors as Novel Predictive Markers in Melanoma Treatment with Ipilimumab

    National Research Council Canada - National Science Library

    Gebhardt, Christoffer; Sevko, Alexandra; Jiang, Huanhuan; Lichtenberger, Ramtin; Reith, Maike; Tarnanidis, Kathrin; Holland-Letz, Tim; Umansky, Ludmila; Beckhove, Philipp; Sucker, Antje; Schadendorf, Dirk; Utikal, Jochen; Umansky, Viktor

    2015-01-01

    .... We performed an analysis of myeloid cells in the peripheral blood of 59 stage IV melanoma patients before the treatment and at different time points upon the therapy using a clinical laboratory...

  18. Cryptic collagen IV promotes cell migration and adhesion in myeloid leukemia.

    Science.gov (United States)

    Favreau, Amanda J; Vary, Calvin P H; Brooks, Peter C; Sathyanarayana, Pradeep

    2014-04-01

    Previously, we showed that discoidin domain receptor 1 (DDR1), a class of collagen-activated receptor tyrosine kinase (RTK) was highly upregulated on bone marrow (BM)-derived CD33+ leukemic blasts of acute myeloid leukemia (AML) patients. Herein as DDR1 is a class of collagen-activated RTK, we attempt to understand the role of native and remodeled collagen IV in BM microenvironment and its functional significance in leukemic cells. Exposure to denatured collagen IV significantly increased the migration and adhesion of K562 cells, which also resulted in increased activation of DDR1 and AKT. Further, levels of MMP9 were increased in conditioned media (CM) of denatured collagen IV exposed cells. Mass spectrometric liquid chromatography/tandem mass spectrometry QSTAR proteomic analysis revealed exclusive presence of Secretogranin 3 and InaD-like protein in the denatured collagen IV CM. Importantly, BM samples of AML patients exhibited increased levels of remodeled collagen IV compared to native as analyzed via anti-HUIV26 antibody. Taken together, for the first time, we demonstrate that remodeled collagen IV is a potent activator of DDR1 and AKT that also modulates both migration and adhesion of myeloid leukemia cells. Additionally, high levels of the HUIV26 cryptic collagen IV epitope are expressed in BM of AML patients. Further understanding of this phenomenon may lead to the development of therapeutic agents that directly modulate the BM microenvironment and attenuate leukemogenesis.

  19. Program death-1 signaling and regulatory T cells collaborate to resist the function of adoptively transferred cytotoxic T lymphocytes in advanced acute myeloid leukemia

    National Research Council Canada - National Science Library

    Zhou, Qing; Munger, Meghan E; Highfill, Steven L; Tolar, Jakub; Weigel, Brenda J; Riddle, Megan; Sharpe, Arlene H; Vallera, Daniel A; Azuma, Miyuki; Levine, Bruce L; June, Carl H; Murphy, William J; Munn, David H; Blazar, Bruce R

    2010-01-01

    ...) and elevation of program death-1 (PD-1) expression on CD8(+) cytotoxic T cells (CTLs) at the tumor site. PD-1 knockout mice were more resistant to AML despite the presence of similar percentage of Tregs compared with wild type...

  20. Myeloid cells are capable of synthesizing aldosterone to exacerbate damage in muscular dystrophy.

    Science.gov (United States)

    Chadwick, Jessica A; Swager, Sarah A; Lowe, Jeovanna; Welc, Steven S; Tidball, James G; Gomez-Sanchez, Celso E; Gomez-Sanchez, Elise P; Rafael-Fortney, Jill A

    2016-12-01

    FDA-approved mineralocorticoid receptor (MR) antagonists are used to treat heart failure. We have recently demonstrated efficacy of MR antagonists for skeletal muscles in addition to heart in Duchenne muscular dystrophy mouse models and that mineralocorticoid receptors are present and functional in skeletal muscles. The goal of this study was to elucidate the underlying mechanisms of MR antagonist efficacy on dystrophic skeletal muscles. We demonstrate for the first time that infiltrating myeloid cells clustered in damaged areas of dystrophic skeletal muscles have the capacity to produce the natural ligand of MR, aldosterone, which in excess is known to exacerbate tissue damage. Aldosterone synthase protein levels are increased in leukocytes isolated from dystrophic muscles compared with controls and local aldosterone levels in dystrophic skeletal muscles are increased, despite normal circulating levels. All genes encoding enzymes in the pathway for aldosterone synthesis are expressed in muscle-derived leukocytes. 11β-HSD2, the enzyme that inactivates glucocorticoids to increase MR selectivity for aldosterone, is also increased in dystrophic muscle tissues. These results, together with the demonstrated preclinical efficacy of antagonists, suggest MR activation is in excess of physiological need and likely contributes to the pathology of muscular dystrophy. This study provides new mechanistic insight into the known contribution of myeloid cells to muscular dystrophy pathology. This first report of myeloid cells having the capacity to produce aldosterone may have implications for a wide variety of acute injuries and chronic diseases with inflammation where MR antagonists may be therapeutic. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Differential Regulation of Myeloid-Derived Suppressor Cells by Candida Species

    Science.gov (United States)

    Singh, Anurag; Lelis, Felipe; Braig, Stefanie; Schäfer, Iris; Hartl, Dominik; Rieber, Nikolaus

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) are innate immune cells characterized by their ability to suppress T-cell responses. Recently, we demonstrated that the human-pathogenic fungi Candida albicans and Aspergillus fumigatus induced a distinct subset of neutrophilic MDSCs. To dissect Candida-mediated MDSC induction in more depth, we studied the relative efficacy of different pathogenic non-albicans Candida species to induce and functionally modulate neutrophilic MDSCs, including C. glabrata, C. parapsilosis, C. dubliniensis, and C. krusei. Our data demonstrate that the extent of MDSC generation is largely dependent on the Candida species with MDSCs induced by C. krusei and C. glabrata showing a higher suppressive activity compared to MDSCs induced by C. albicans. In summary, these studies show that fungal MDSC induction is differentially regulated at the species level and differentially affects effector T-cell responses.

  2. TISSUE FACTOR EXPRESSION BY MYELOID CELLS CONTRIBUTES TO PROTECTIVE IMMUNE RESPONSE AGAINST Mycobacterium tuberculosis INFECTION

    Science.gov (United States)

    Venkatasubramanian, Sambasivan; Tripathi, Deepak; Tucker, Torry; Paidipally, Padmaja; Cheekatla, Satyanarayana; Welch, Elwyn; Raghunath, Anjana; Jeffers, Ann; Tvinnereim, Amy R.; Schechter, Melissa E; Andrade, Bruno B; Mackman, Nizel; Idell, Steven; Vankayalapati, Ramakrishna

    2015-01-01

    Tissue Factor (TF) is a transmembrane glycoprotein that plays an essential role in hemostasis by activating coagulation. TF is also expressed by monocytes/macrophages as part of the innate immune response to infections. In the current study, we determined the role of TF expressed by myeloid cells during Mycobacterium tuberculosis (M. tb) infection by using mice lacking the TF gene in myeloid cells (TFΔ) and human monocyte derived macrophages (MDMs). We found that during M. tb infection, a deficiency of TF in myeloid cells was associated with reduced inducible nitric oxide synthase (iNOS) expression, enhanced arginase 1 (Arg1) expression, enhanced IL-10 production and reduced apoptosis in infected macrophages, which augmented M. tb growth. Our results demonstrate that a deficiency of TF in myeloid cells promotes M2 like phenotype in M .tb infected macrophages. A deficiency in TF expression by myeloid cells was also associated with reduced fibrin deposition and increased matrix metalloproteases (MMP)-2 and MMP-9 mediated inflammation in M. tb infected lungs. Our studies demonstrate that TF expressed by myeloid cells has newly recognized abilities to polarize macrophages and to regulate M. tb growth. PMID:26471500

  3. Characterization of miRNomes in Acute and Chronic Myeloid Leukemia Cell Lines

    Institute of Scientific and Technical Information of China (English)

    Qian Xiong; Jiangwei Yan; Songnian Hu; Xiangdong Fang; Yadong Yang; Hai Wang; Jie Li; Shaobin Wang; Yanming Li; Yaran Yang; Kan Cai; Xiuyan Ruan

    2014-01-01

    Myeloid leukemias are highly diverse diseases and have been shown to be associated with microRNA (miRNA) expression aberrations. The present study involved an in-depth miRNome analysis of two human acute myeloid leukemia (AML) cell lines, HL-60 and THP-1, and one human chronic myeloid leukemia (CML) cell line, K562, via massively parallel signature sequenc-ing. mRNA expression profiles of these cell lines that were established previously in our lab facil-itated an integrative analysis of miRNA and mRNA expression patterns. miRNA expression profiling followed by differential expression analysis and target prediction suggested numerous miRNA signatures in AML and CML cell lines. Some miRNAs may act as either tumor suppres-sors or oncomiRs in AML and CML by targeting key genes in AML and CML pathways. Expres-sion patterns of cell type-specific miRNAs could partially reflect the characteristics of K562, HL-60 and THP-1 cell lines, such as actin filament-based processes, responsiveness to stimulus and phag-ocytic activity. miRNAs may also regulate myeloid differentiation, since they usually suppress dif-ferentiation regulators. Our study provides a resource to further investigate the employment of miRNAs in human leukemia subtyping, leukemogenesis and myeloid development. In addition, the distinctive miRNA signatures may be potential candidates for the clinical diagnosis, prognosis and treatment of myeloid leukemias.

  4. Deletion of ADORA2B from myeloid cells dampens lung fibrosis and pulmonary hypertension.

    Science.gov (United States)

    Karmouty-Quintana, Harry; Philip, Kemly; Acero, Luis F; Chen, Ning-Yuan; Weng, Tingting; Molina, Jose G; Luo, Fayong; Davies, Jonathan; Le, Ngoc-Bao; Bunge, Isabelle; Volcik, Kelly A; Le, Thanh-Thuy T; Johnston, Richard A; Xia, Yang; Eltzschig, Holger K; Blackburn, Michael R

    2015-01-01

    Idiopathic pulmonary fibrosis (IPF) is a lethal, fibroproliferative disease. Pulmonary hypertension (PH) can develop secondary to IPF and increase mortality. Alternatively, activated macrophages (AAMs) contribute to the pathogenesis of both IPF and PH. Here we hypothesized that adenosine signaling through the ADORA2B on AAMs impacts the progression of these disorders and that conditional deletion of ADORA2B on myeloid cells would have a beneficial effect in a model of these diseases. Conditional knockout mice lacking ADORA2B on myeloid cells (Adora2B(f/f)-LysM(Cre)) were exposed to the fibrotic agent bleomycin (BLM; 0.035 U/g body weight, i.p.). At 14, 17, 21, 25, or 33 d after exposure, SpO2, bronchoalveolar lavage fluid (BALF), and histologic analyses were performed. On day 33, lung function and cardiovascular analyses were determined. Markers for AAM and mediators of fibrosis and PH were assessed. Adora2B(f/f)-LysM(Cre) mice presented with attenuated fibrosis, improved lung function, and no evidence of PH compared with control mice exposed to BLM. These findings were accompanied by reduced expression of CD206 and arginase-1, markers for AAMs. A 10-fold reduction in IL-6 and a 5-fold decrease in hyaluronan, both linked to lung fibrosis and PH, were also observed. These data suggest that activation of the ADORA2B on macrophages plays an active role in the pathogenesis of lung fibrosis and PH.

  5. Tumor-associated myeloid cells as guiding forces of cancer cell stemness.

    Science.gov (United States)

    Sica, Antonio; Porta, Chiara; Amadori, Alberto; Pastò, Anna

    2017-08-01

    Due to their ability to differentiate into various cell types and to support tissue regeneration, stem cells simultaneously became the holy grail of regenerative medicine and the evil obstacle in cancer therapy. Several studies have investigated niche-related conditions that favor stemness properties and increasingly emphasized their association with an inflammatory environment. Tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs) are major orchestrators of cancer-related inflammation, able to dynamically express different polarized inflammatory programs that promote tumor outgrowth, including tumor angiogenesis, immunosuppression, tissue remodeling and metastasis formation. In addition, these myeloid populations support cancer cell stemness, favoring tumor maintenance and progression, as well as resistance to anticancer treatments. Here, we discuss inflammatory circuits and molecules expressed by TAMs and MDSCs as guiding forces of cancer cell stemness.

  6. The immunosuppressive tumour network: myeloid-derived suppressor cells, regulatory T cells and natural killer T cells.

    NARCIS (Netherlands)

    Lindau, D.S.U.; Gielen, P.R.; Kroesen, M.; Wesseling, P.; Adema, G.J.

    2013-01-01

    Myeloid-derived suppressor cells (MDSC) and regulatory T (Treg) cells are major components of the immune suppressive tumour microenvironment (TME). Both cell types expand systematically in preclinical tumour models and promote T-cell dysfunction that in turn favours tumour progression. Clinical repo

  7. MicroRNA-126-mediated control of cell fate in B-cell myeloid progenitors as a potential alternative to transcriptional factors.

    Science.gov (United States)

    Okuyama, Kazuki; Ikawa, Tomokatsu; Gentner, Bernhard; Hozumi, Katsuto; Harnprasopwat, Ratanakanit; Lu, Jun; Yamashita, Riu; Ha, Daon; Toyoshima, Takae; Chanda, Bidisha; Kawamata, Toyotaka; Yokoyama, Kazuaki; Wang, Shusheng; Ando, Kiyoshi; Lodish, Harvey F; Tojo, Arinobu; Kawamoto, Hiroshi; Kotani, Ai

    2013-08-13

    Lineage specification is thought to be largely regulated at the level of transcription, where lineage-specific transcription factors drive specific cell fates. MicroRNAs (miR), vital to many cell functions, act posttranscriptionally to decrease the expression of target mRNAs. MLL-AF4 acute lymphocytic leukemia exhibits both myeloid and B-cell surface markers, suggesting that the transformed cells are B-cell myeloid progenitor cells. Through gain- and loss-of-function experiments, we demonstrated that microRNA 126 (miR-126) drives B-cell myeloid biphenotypic leukemia differentiation toward B cells without changing expression of E2A immunoglobulin enhancer-binding factor E12/E47 (E2A), early B-cell factor 1 (EBF1), or paired box protein 5, which are critical transcription factors in B-lymphopoiesis. Similar induction of B-cell differentiation by miR-126 was observed in normal hematopoietic cells in vitro and in vivo in uncommitted murine c-Kit(+)Sca1(+)Lineage(-) cells, with insulin regulatory subunit-1 acting as a target of miR-126. Importantly, in EBF1-deficient hematopoietic progenitor cells, which fail to differentiate into B cells, miR-126 significantly up-regulated B220, and induced the expression of B-cell genes, including recombination activating genes-1/2 and CD79a/b. These data suggest that miR-126 can at least partly rescue B-cell development independently of EBF1. These experiments show that miR-126 regulates myeloid vs. B-cell fate through an alternative machinery, establishing the critical role of miRNAs in the lineage specification of multipotent mammalian cells.

  8. Anthrax toxin targeting of myeloid cells through the CMG2 receptor is essential for establishment of Bacillus anthracis infections in mice

    Science.gov (United States)

    Liu, Shihui; Miller-Randolph, Sharmina; Crown, Devorah; Moayeri, Mahtab; Sastalla, Inka; Okugawa, Shu; Leppla, Stephen H.

    2010-01-01

    SUMMARY Bacillus anthracis kills through a combination of bacterial infection and toxemia. Anthrax toxin working via the CMG2 receptor mediates lethality late in infection, but its roles early in infection remain unclear. We generated myeloid-lineage specific CMG2-deficient mice to examine the roles of macrophages, neutrophils, and other myeloid cells in anthrax pathogenesis. Macrophages and neutrophils isolated from these mice were resistant to anthrax toxin. However, the myeloid-specific CMG2-deficient mice remained fully sensitive to both anthrax lethal and edema toxins, demonstrating that targeting of myeloid cells is not responsible for anthrax toxin-induced lethality. Surprisingly, the myeloid-specific CMG2-deficient mice were completely resistant to B. anthracis infection. Neutrophil depletion experiments suggest that B. anthracis relies on anthrax toxin secretion to evade the scavenging functions of neutrophils to successfully establish infection. This work demonstrates that anthrax toxin uptake through CMG2 and the resulting impairment of myeloid cells specifically neutrophils, is essential to anthrax infection. PMID:21075356

  9. Chronic interleukin-1 exposure drives haematopoietic stem cells towards precocious myeloid differentiation at the expense of self-renewal.

    Science.gov (United States)

    Pietras, Eric M; Mirantes-Barbeito, Cristina; Fong, Sarah; Loeffler, Dirk; Kovtonyuk, Larisa V; Zhang, SiYi; Lakshminarasimhan, Ranjani; Chin, Chih Peng; Techner, José-Marc; Will, Britta; Nerlov, Claus; Steidl, Ulrich; Manz, Markus G; Schroeder, Timm; Passegué, Emmanuelle

    2016-06-01

    Haematopoietic stem cells (HSCs) maintain lifelong blood production and increase blood cell numbers in response to chronic and acute injury. However, the mechanism(s) by which inflammatory insults are communicated to HSCs and their consequences for HSC activity remain largely unknown. Here, we demonstrate that interleukin-1 (IL-1), which functions as a key pro-inflammatory 'emergency' signal, directly accelerates cell division and myeloid differentiation of HSCs through precocious activation of a PU.1-dependent gene program. Although this effect is essential for rapid myeloid recovery following acute injury to the bone marrow, chronic IL-1 exposure restricts HSC lineage output, severely erodes HSC self-renewal capacity, and primes IL-1-exposed HSCs to fail massive replicative challenges such as transplantation. Importantly, these damaging effects are transient and fully reversible on IL-1 withdrawal. Our results identify a critical regulatory circuit that tailors HSC responses to acute needs, and is likely to underlie deregulated blood homeostasis in chronic inflammation conditions.

  10. Myeloid and lymphoid contribution to non-haematopoietic lineages through irradiation-induced heterotypic cell fusion

    DEFF Research Database (Denmark)

    Nygren, J.M.; Liuba, K.; Breitbach, M.;

    2008-01-01

    and Purkinje neurons. However, through lineage fate-mapping we demonstrate that such in vivo fusion of lymphoid and myeloid blood cells does not occur to an appreciable extent in steady-state adult tissues or during normal development. Rather, fusion of blood cells with different non-haematopoietic cell types...... is induced by organ-specific injuries or whole-body irradiation, which has been used in previous studies to condition recipients of bone marrow transplants. Our findings demonstrate that blood cells of the lymphoid and myeloid lineages contribute to various non-haematopoietic tissues by forming rare fusion......Recent studies have suggested that regeneration of non-haematopoietic cell lineages can occur through heterotypic cell fusion with haematopoietic cells of the myeloid lineage. Here we show that lymphocytes also form heterotypic-fusion hybrids with cardiomyocytes, skeletal muscle, hepatocytes...

  11. The Role and Potential Therapeutic Application of Myeloid-Derived Suppressor Cells in Allo- and Autoimmunity

    Directory of Open Access Journals (Sweden)

    Qi Zhang

    2015-01-01

    Full Text Available Myeloid-derived suppressor cells (MDSCs are a heterogeneous population of cells that consists of myeloid progenitor cells and immature myeloid cells. They have been identified as a cell population that may affect the activation of CD4+ and CD8+ T-cells to regulate the immune response negatively, which makes them attractive targets for the treatment of transplantation and autoimmune diseases. Several studies have suggested the potential suppressive effect of MDSCs on allo- and autoimmune responses. Conversely, MDSCs have also been found at various stages of differentiation, accumulating during pathological situations, not only during tumor development but also in a variety of inflammatory immune responses, bone marrow transplantation, and some autoimmune diseases. These findings appear to be contradictory. In this review, we summarize the roles of MDSCs in different transplantation and autoimmune diseases models as well as the potential to target these cells for therapeutic benefit.

  12. What Is Chronic Myeloid Leukemia?

    Science.gov (United States)

    ... Chronic Myeloid Leukemia (CML) About Chronic Myeloid Leukemia What Is Chronic Myeloid Leukemia? Cancer starts when cells ... their treatment is the same as for adults. What is leukemia? Leukemia is a cancer that starts ...

  13. Expression of maturation-specific nuclear antigens in differentiating human myeloid leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Murao, S.; Epstein, A.L.; Clevenger, C.V.; Huberman, E.

    1985-02-01

    The expression of three myeloid-specific nuclear antigens was studied by indirect immunofluorescence with murine monoclonal antibodies in human myeloid (HL-60, ML-2, KG-1, and B-II) leukemia cells treated with chemical inducers of cell differentiation. Treatment of the promyelocytic HL-60 cells with dimethyl sulfoxide or 1,25-dihydroxyvitamin DT induced the cells to acquire a phenotype that resembled that of granulocytes and monocytesmacrophages, respectively. These phenotypes were characterized by changes in cell growth, cell morphology, expression of specific cell surface antigens, and activities of lysozyme and nonspecific esterase enzymes. Induction of these differentiation markers in the HL-60 cells was associated with induction of the myeloid-specific nuclear antigens. The ML-2 cells, which are arrested at the myeloblast-promyelocyte stage, were also susceptible to the induction of cell differentiation and to changes in the expression of the nuclear antigens, but the degree of susceptibility was less than in the HL-60 cells. The less-differentiated KG-1 and B-II myeloid cells were either not responsive or responded only in a limited degree to the induction of cell differentiation or to changes in the expression of the nuclear antigens. The authors suggest that the reactivity of cells with monoclonal antibodies to specific nuclear antigens can be used as a maturational marker in cell differentiation studies. Furthermore, nuclear antigens expressed early in cellular differentiation may provide information about changes in regulatory elements in normal and malignant cells. 40 references, 2 figures, 1 table.

  14. Monoclonal Antibody Therapy in Treating Patients With Ovarian Epithelial Cancer, Melanoma, Acute Myeloid Leukemia, Myelodysplastic Syndrome, or Non-Small Cell Lung Cancer

    Science.gov (United States)

    2013-01-09

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative; Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Myeloid Leukemia; Recurrent Melanoma; Recurrent Non-small Cell Lung Cancer; Recurrent Ovarian Epithelial Cancer; Stage IV Melanoma; Stage IV Non-small Cell Lung Cancer

  15. Lack of PPARγ in myeloid cells confers resistance to Listeria monocytogenes infection.

    Directory of Open Access Journals (Sweden)

    Zeinab Abdullah

    Full Text Available The peroxisomal proliferator-activated receptor γ (PPARγ is a nuclear receptor that controls inflammation and immunity. Innate immune defense against bacterial infection appears to be compromised by PPARγ. The relevance of PPARγ in myeloid cells, that organize anti-bacterial immunity, for the outcome of immune responses against intracellular bacteria such as Listeria monocytogenes in vivo is unknown. We found that Listeria monocytogenes infection of macrophages rapidly led to increased expression of PPARγ. This prompted us to investigate whether PPARγ in myeloid cells influences innate immunity against Listeria monocytogenes infection by using transgenic mice with myeloid-cell specific ablation of PPARγ (LysMCre×PPARγ(flox/flox. Loss of PPARγ in myeloid cells results in enhanced innate immune defense against Listeria monocytogenes infection both, in vitro and in vivo. This increased resistance against infection was characterized by augmented levels of bactericidal factors and inflammatory cytokines: ROS, NO, IFNγ TNF IL-6 and IL-12. Moreover, myeloid cell-specific loss of PPARγ enhanced chemokine and adhesion molecule expression leading to improved recruitment of inflammatory Ly6C(hi monocytes to sites of infection. Importantly, increased resistance against Listeria infection in the absence of PPARγ was not accompanied by enhanced immunopathology. Our results elucidate a yet unknown regulatory network in myeloid cells that is governed by PPARγ and restrains both listeriocidal activity and recruitment of inflammatory monocytes during Listeria infection, which may contribute to bacterial immune escape. Pharmacological interference with PPARγ activity in myeloid cells might represent a novel strategy to overcome intracellular bacterial infection.

  16. Myeloid dendritic cells frequencies are increased in children with autism spectrum disorder and associated with amygdala volume and repetitive behaviors.

    Science.gov (United States)

    Breece, Elizabeth; Paciotti, Brian; Nordahl, Christine Wu; Ozonoff, Sally; Van de Water, Judy A; Rogers, Sally J; Amaral, David; Ashwood, Paul

    2013-07-01

    The pathophysiology of autism spectrum disorder (ASD) is not yet known; however, studies suggest that dysfunction of the immune system affects many children with ASD. Increasing evidence points to dysfunction of the innate immune system including activation of microglia and perivascular macrophages, increases in inflammatory cytokines/chemokines in brain tissue and CSF, and abnormal peripheral monocyte cell function. Dendritic cells are major players in innate immunity and have important functions in the phagocytosis of pathogens or debris, antigen presentation, activation of naïve T cells, induction of tolerance and cytokine/chemokine production. In this study, we assessed circulating frequencies of myeloid dendritic cells (defined as Lin-1(-)BDCA1(+)CD11c(+) and Lin-1(-)BDCA3(+)CD123(-)) and plasmacytoid dendritic cells (Lin-1(-)BDCA2(+)CD123(+) or Lin-1(-)BDCA4(+) CD11c(-)) in 57 children with ASD, and 29 typically developing controls of the same age, all of who were enrolled as part of the Autism Phenome Project (APP). The frequencies of dendritic cells and associations with behavioral assessment and MRI measurements of amygdala volume were compared in the same participants. The frequencies of myeloid dendritic cells were significantly increased in children with ASD compared to typically developing controls (pfrequencies of myeloid dendritic cells were positively associated with abnormal right and left amygdala enlargement, severity of gastrointestinal symptoms and increased repetitive behaviors. The frequencies of plasmacytoid dendritic cells were also associated with amygdala volumes as well as developmental regression in children with ASD. Dendritic cells play key roles in modulating immune responses and differences in frequencies or functions of these cells may result in immune dysfunction in children with ASD. These data further implicate innate immune cells in the complex pathophysiology of ASD.

  17. TAP-deficient human iPS cell-derived myeloid cell lines as unlimited cell source for dendritic cell-like antigen-presenting cells.

    Science.gov (United States)

    Haruta, M; Tomita, Y; Yuno, A; Matsumura, K; Ikeda, T; Takamatsu, K; Haga, E; Koba, C; Nishimura, Y; Senju, S

    2013-05-01

    We previously reported a method to generate dendritic cell (DC)-like antigen-presenting cells (APC) from human induced pluripotent stem (iPS) cells. However, the method is relatively complicated and laborious. In the current study, we attempted to establish a method through which we could obtain a large number of functional APC with a simple procedure. We transduced iPS cell-derived CD11b(+) myeloid cells with genes associated with proliferative or anti-senescence effects, enabling the cells to propagate for more than 4 months in a macrophage colony-stimulating factor (M-CSF)-dependent manner while retaining their capacity to differentiate into functional APC. We named these iPS cell-derived proliferating myeloid cells 'iPS-ML', and the iPS-ML-derived APC 'ML-DC'. In addition, we generated TAP2-deficient iPS cell clones by zinc finger nuclease-aided targeted gene disruption. TAP2-deficient iPS cells and iPS-ML avoided recognition by pre-activated allo-reactive CD8(+) T cells. TAP2-deficient ML-DC expressing exogenously introduced HLA-A2 genes stimulated HLA-A2-restricted MART-1-specific CD8(+) T cells obtained from HLA-A2-positive allogeneic donors, resulting in generation of MART-1-specific cytotoxic T lymphocyte (CTL) lines. TAP-deficient iPS-ML introduced with various HLA class I genes may serve as an unlimited source of APC for vaccination therapy. If administered into allogeneic patients, ML-DC with appropriate genetic modifications may survive long enough to stimulate antigen-specific CTL and, after that, be completely eliminated. Based on the present study, we propose an APC-producing system that is simple, safe and applicable to all patients irrespective of their HLA types.

  18. Genome-Wide CRISPR-Cas9 Screen Identifies MicroRNAs That Regulate Myeloid Leukemia Cell Growth

    OpenAIRE

    Wallace, Jared; Hu, Ruozhen; Mosbruger, Timothy L.; Dahlem, Timothy J.; Stephens, W. Zac; Rao, Dinesh S.; Round, June L.; O’Connell, Ryan M.

    2016-01-01

    Mammalian microRNA expression is dysregulated in human cancer. However, the functional relevance of many microRNAs in the context of tumor biology remains unclear. Using CRISPR-Cas9 technology, we performed a global loss-of-function screen to simultaneously test the functions of individual microRNAs and protein-coding genes during the growth of a myeloid leukemia cell line. This approach identified evolutionarily conserved human microRNAs that suppress or promote cell growth, revealing that m...

  19. Effect of Synthesized hTERT Epitopes on the Phenotype and Function of Myeloid Dendritic Cells%人工合成树状串联hTERT表位肽对mDC表型和功能的影响

    Institute of Scientific and Technical Information of China (English)

    钮柏琳; 慎华平; 杜慧敏; 杨仕明; 邹利全; 龚建平

    2011-01-01

    目的 通过对树状串联hTERT表位肽(MAP)与无肽刺激组髓样树突状细胞(mDC)的相关检测,研究MAP肽对mDC的表型和功能的影响.方法 人工固相合成四分支的MAP肽,免疫磁珠分选mDC,流式细胞技术检测相关表面分子.ElISA分别检测两组mDC培养基的IL-12p70含量,并作统计学分析.结果 人工合成MAP肽纯度高(95.26 %),免疫磁珠分选mDC纯度为72.59 %,相比于无肽刺激组mDC,MAP肽刺激组成熟(培养第9天)时MHCⅡ类分子为83.90 %、MHCⅠ类分子为91.08 %,CD86:77.03 %,CD83:92.16 %;IL-12p70的含量也大于无肽刺激组,且有统计学差异.结论 人工合成hTERT的MAP肽能足够强的激活mDC,刺激其成熟和功能的表达,可作为mDC抗肿瘤疫苗的刺激肽结构.%Objective To explore the role of tandem multiple antigenic peptide ( MAP ) on myeloid dengritic cells ( mDC ), by comparing the phenotype and function of mDC stimulated by MAP of human telomerase reverse transcriptase ( hTERT ) epitopes to the control group cells. Methods Four branches of MAP peptides were solid-phase artificially synthesized. mDC cells were isolated through magnetic activated cell sorting ( MACS ) . The surface molecules of mDC were detected by flow cytometry. The level of IL-12 p70 was detected by ELISA on both groups respectively and statistically analyzed. Results Synthetic MAP peptide was synthesized with high purity ( 95. 26 %) . The rate of mDC with magnetic activated cell sorting was 72. 59% . In MAP peptide stimulated group, MHC Ⅱ molecules reached 83. 90% , MHCI 91. 08%, CD86 77. 03% , and CD83 92. 16% , while the control group was 12. 92%. 64. 88% . 14. 45% and 26. 32%, when matured in 9-day culture. IL-12p70 secretion was higher than that in the control group, with significant difference. Conclusion The synthesized MAP peptides of hTERT can strongly activate mDC,thus can be used as stimulating peptides in anti-tumor vaccine research.

  20. Phenotypic and functional plasticity of cells of innate immunity: macrophages, mast cells and neutrophils

    DEFF Research Database (Denmark)

    Galli, Stephen J; Borregaard, Niels; Wynn, Thomas A

    2011-01-01

    Hematopoietic cells, including lymphoid and myeloid cells, can develop into phenotypically distinct 'subpopulations' with different functions. However, evidence indicates that some of these subpopulations can manifest substantial plasticity (that is, undergo changes in their phenotype and functio...

  1. Immunodetection of myeloid and plasmacytoid dendritic cells in mammary carcinomas of female dogs

    Directory of Open Access Journals (Sweden)

    Mayara C. Rosolem

    2015-11-01

    Full Text Available ABSTRACT: Dendritic cells have attracted great interest from researchers as they may be used as targets of tumor immune evasion mechanisms. The main objective of this study was to evaluate the relationship between the dendritic cells (DCs subpopulation in simple type mammary carcinomas in female dogs. Two groups of samples were used: the control group consisted of 18 samples of mammary tissue without changes and the tumor group with 26 simple type mammary carcinomas. In these groups, we evaluated the immunodetection of immature and mature myeloid DCs, plasmacytoid DCs and MHC-II. In mammary tumor, mature myeloid DCs predominated in the peritumoral region, while immature myeloid DCs and plasmacytoid DCs were evident in the intratumoral region. Immunostaining of MHC-II was visualized in mammary acini (control group, in tumor cells and inflammatory infiltration associated with tumors. The comparison between the control and tumor groups showed a statistically significant difference between immature myeloid DCs, mature myeloid DCs and plasmacytoid DCs. The immunodetection of MHC-II was not significant when comparing the groups. The predominance of immature DCs in the tumor group is possibly related to an inefficient immune response, promoting the development and survival of tumor cells. The presence of plasmacytoid DCs in the same group suggests a worse prognosis for female dogs with mammary tumors. Therefore, the ability of differentiation of canine dendritic cells could be influenced by neoplastic cells and by the tumor microenvironment.

  2. Pam2 lipopeptides systemically increase myeloid-derived suppressor cells through TLR2 signaling

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Akira; Shime, Hiroaki, E-mail: shime@med.hokudai.ac.jp; Takeda, Yohei; Azuma, Masahiro; Matsumoto, Misako; Seya, Tsukasa, E-mail: seya-tu@pop.med.hokudai.ac.jp

    2015-02-13

    Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells that exhibit potent immunosuppressive activity. They are increased in tumor-bearing hosts and contribute to tumor development. Toll-like receptors (TLRs) on MDSCs may modulate the tumor-supporting properties of MDSCs through pattern-recognition. Pam2 lipopeptides represented by Pam2CSK4 serve as a TLR2 agonist to exert anti-tumor function by dendritic cell (DC)-priming that leads to NK cell activation and cytotoxic T cell proliferation. On the other hand, TLR2 enhances tumor cell progression/invasion by activating tumor-infiltrating macrophages. How MDSCs respond to TLR2 agonists has not yet been determined. In this study, we found intravenous administration of Pam2CSK4 systemically up-regulated the frequency of MDSCs in EG7 tumor-bearing mice. The frequency of tumor-infiltrating MDSCs was accordingly increased in response to Pam2CSK4. MDSCs were not increased by Pam2CSK4 stimuli in TLR2 knockout (KO) mice. Adoptive transfer experiments using CFSE-labeled MDSCs revealed that the TLR2-positive MDSCs survived long in tumor-bearing mice in response to Pam2CSK4 treatment. Since the increased MDSC population sustained immune-suppressive properties, our study suggests that Pam2CSK4-triggered TLR2 activation enhances the MDSC potential and suppress antitumor immune response in tumor microenvironment. - Highlights: • Pam2CSK4 administration induces systemic accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • TLR2 is essential for Pam2CSK4-induced accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • Pam2CSK4 supports survival of CD11b{sup +}Gr1{sup +} MDSCs in vivo.

  3. Central nervous system myeloid cells as drug targets: current status and translational challenges.

    Science.gov (United States)

    Biber, Knut; Möller, Thomas; Boddeke, Erik; Prinz, Marco

    2016-02-01

    Myeloid cells of the central nervous system (CNS), which include parenchymal microglia, macrophages at CNS interfaces and monocytes recruited from the circulation during disease, are increasingly being recognized as targets for therapeutic intervention in neurological and psychiatric diseases. The origin of these cells in the immune system distinguishes them from ectodermal neurons and other glia and endows them with potential drug targets distinct from classical CNS target groups. However, despite the identification of several promising therapeutic approaches and molecular targets, no agents directly targeting these cells are currently available. Here, we assess strategies for targeting CNS myeloid cells and address key issues associated with their translation into the clinic.

  4. Systemic T Cells Immunosuppression of Glioma Stem Cell-Derived Exosomes Is Mediated by Monocytic Myeloid-Derived Suppressor Cells.

    Science.gov (United States)

    Domenis, Rossana; Cesselli, Daniela; Toffoletto, Barbara; Bourkoula, Evgenia; Caponnetto, Federica; Manini, Ivana; Beltrami, Antonio Paolo; Ius, Tamara; Skrap, Miran; Di Loreto, Carla; Gri, Giorgia

    2017-01-01

    A major contributing factor to glioma development and progression is its ability to evade the immune system. Nano-meter sized vesicles, exosomes, secreted by glioma-stem cells (GSC) can act as mediators of intercellular communication to promote tumor immune escape. Here, we investigated the immunomodulatory properties of GCS-derived exosomes on different peripheral immune cell populations. Healthy donor peripheral blood mononuclear cells (PBMCs) stimulated with anti-CD3, anti-CD28 and IL-2, were treated with GSC-derived exosomes. Phenotypic characterization, cell proliferation, Th1/Th2 cytokine secretion and intracellular cytokine production were analysed by distinguishing among effector T cells, regulatory T cells and monocytes. In unfractionated PBMCs, GSC-derived exosomes inhibited T cell activation (CD25 and CD69 expression), proliferation and Th1 cytokine production, and did not affect cell viability or regulatory T-cell suppression ability. Furthermore, exosomes were able to enhance proliferation of purified CD4+ T cells. In PBMCs culture, glioma-derived exosomes directly promoted IL-10 and arginase-1 production and downregulation of HLA-DR by unstimulated CD14+ monocytic cells, that displayed an immunophenotype resembling that of monocytic myeloid-derived suppressor cells (Mo-MDSCs). Importantly, the removal of CD14+ monocytic cell fraction from PBMCs restored T-cell proliferation. The same results were observed with exosomes purified from plasma of glioblastoma patients. Our results indicate that glioma-derived exosomes suppress T-cell immune response by acting on monocyte maturation rather than on direct interaction with T cells. Selective targeting of Mo-MDSC to treat glioma should be considered with regard to how immune cells allow the acquirement of effector functions and therefore counteracting tumor progression.

  5. Cysteine cathepsin activity suppresses osteoclastogenesis of myeloid-derived suppressor cells in breast cancer.

    Science.gov (United States)

    Edgington-Mitchell, Laura E; Rautela, Jai; Duivenvoorden, Hendrika M; Jayatilleke, Krishnath M; van der Linden, Wouter A; Verdoes, Martijn; Bogyo, Matthew; Parker, Belinda S

    2015-09-29

    Cysteine cathepsin proteases contribute to many normal cellular functions, and their aberrant activity within various cell types can contribute to many diseases, including breast cancer. It is now well accepted that cathepsin proteases have numerous cell-specific functions within the tumor microenvironment that function to promote tumor growth and invasion, such that they may be valid targets for anti-metastatic therapeutic approaches. Using activity-based probes, we have examined the activity and expression of cysteine cathepsins in a mouse model of breast cancer metastasis to bone. In mice bearing highly metastatic tumors, we detected abundant cysteine cathepsin expression and activity in myeloid-derived suppressor cells (MDSCs). These immature immune cells have known metastasis-promoting roles, including immunosuppression and osteoclastogenesis, and we assessed the contribution of cysteine cathepsins to these functions. Blocking cysteine cathepsin activity with multiple small-molecule inhibitors resulted in enhanced differentiation of multinucleated osteoclasts. This highlights a potential role for cysteine cathepsin activity in suppressing the fusion of osteoclast precursor cells. In support of this hypothesis, we found that expression and activity of key cysteine cathepsins were downregulated during MDSC-osteoclast differentiation. Another cysteine protease, legumain, also inhibits osteoclastogenesis, in part through modulation of cathepsin L activity. Together, these data suggest that cysteine protease inhibition is associated with enhanced osteoclastogenesis, a process that has been implicated in bone metastasis.

  6. Radotinib Induces Apoptosis of CD11b+ Cells Differentiated from Acute Myeloid Leukemia Cells.

    Directory of Open Access Journals (Sweden)

    Sook-Kyoung Heo

    Full Text Available Radotinib, developed as a BCR/ABL tyrosine kinase inhibitor (TKI, is approved for the second-line treatment of chronic myeloid leukemia (CML in South Korea. However, therapeutic effects of radotinib in acute myeloid leukemia (AML are unknown. In the present study, we demonstrate that radotinib significantly decreases the viability of AML cells in a dose-dependent manner. Kasumi-1 cells were more sensitive to radotinib than NB4, HL60, or THP-1 cell lines. Furthermore, radotinib induced CD11b expression in NB4, THP-1, and Kasumi-1 cells either in presence or absence of all trans-retinoic acid (ATRA. We found that radotinib promoted differentiation and induced CD11b expression in AML cells by downregulating LYN. However, CD11b expression induced by ATRA in HL60 cells was decreased by radotinib through upregulation of LYN. Furthermore, radotinib mainly induced apoptosis of CD11b+ cells in the total population of AML cells. Radotinib also increased apoptosis of CD11b+ HL60 cells when they were differentiated by ATRA/dasatinib treatment. We show that radotinib induced apoptosis via caspase-3 activation and the loss of mitochondrial membrane potential (ΔΨm in CD11b+ cells differentiated from AML cells. Our results suggest that radotinib may be used as a candidate drug in AML or a chemosensitizer for treatment of AML by other therapeutics.

  7. Deficiency of the Sialyltransferase St3Gal4 Reduces Ccl5-Mediated Myeloid Cell Recruitment and Arrest

    Science.gov (United States)

    Döring, Yvonne; Noels, Heidi; Mandl, Manuela; Kramp, Birgit; Neideck, Carlos; Lievens, Dirk; Drechsler, Maik; Megens, Remco T.A.; Tilstam, Pathricia V.; Langer, Marcella; Hartwig, Helene; Theelen, Wendy; Marth, Jamey D.; Sperandio, Markus; Soehnlein, Oliver; Weber, Christian

    2014-01-01

    Rationale Sialylation by α2,3-sialyltransferases has been shown to be a crucial glycosylation step in the generation of functional selectin ligands. Recent evidence suggests that sialylation also affects the binding of chemokines to their corresponding receptor. Objective Because the chemokine receptors for Ccl5 and Ccl2 are important in atherogenic recruitment of neutrophils and monocytes, we here investigated the role of α2,3-sialyltransferase IV (ST3Gal-IV) in Ccl5- and Ccl2-mediated myeloid cell arrest and further studied its relevance in a mouse model of atherosclerosis. Methods and Results St3Gal4-deficient myeloid cells showed a reduced binding of Ccl5 and an impaired Ccl5-triggered integrin activation. Correspondingly, Ccl5-induced arrest on tumor necrosis factor-α–stimulated endothelium was almost completely abrogated, as observed in flow chamber adhesion assays and during ex vivo perfusion or intravital microscopy of carotid arteries. Moreover, Ccl5-triggered neutrophil and monocyte extravasation into the peritoneal cavity was severely reduced in St3Gal4−/− mice. In contrast, St3Gal4 deficiency did not significantly affect Ccl2 binding and only marginally decreased Ccl2-induced flow arrest of myeloid cells. In agreement with the crucial role of leukocyte accumulation in atherogenesis, and the importance of Ccl5 chemokine receptors mediating myeloid cell recruitment to atherosclerotic vessels, St3Gal4 deficiency drastically reduced the size, stage, and inflammatory cell content of atherosclerotic lesions in Apoe−/− mice on high-fat diet. Conclusions In summary, these findings identify ST3Gal-IV as a promising target to reduce inflammatory leukocyte recruitment and arrest. PMID:24425712

  8. IGK with conserved IGΚV/IGΚJ repertoire is expressed in acute myeloid leukemia and promotes leukemic cell migration.

    Science.gov (United States)

    Wang, Chong; Xia, Miaoran; Sun, Xiaoping; He, Zhiqiao; Hu, Fanlei; Chen, Lei; Bueso-Ramos, Carlos E; Qiu, Xiaoyan; Yin, C Cameron

    2015-11-17

    We have previously reported that immunoglobulin heavy chain genes were expressed in myeloblasts and mature myeloid cells. In this study, we further demonstrated that rearranged Ig κ light chain was also frequently expressed in acute myeloid leukemia cell lines (6/6), primary myeloblasts from patients with acute myeloid leukemia (17/18), and mature monocytes (11/12) and neutrophils (3/12) from patients with non-hematopoietic neoplasms, but not or only rarely expressed in mature neutrophils (0/8) or monocytes (1/8) from healthy individuals. Interestingly, myeloblasts and mature monocytes/neutrophils shared several restricted IGKV and IGKJ gene usages but with different expression frequency. Surprisingly, almost all of the acute myeloid leukemia-derived IGKV showed somatic hypermutation; in contrast, mature myeloid cells-derived IGKV rarely had somatic hypermutation. More importantly, although IGK expression appeared not to affect cell proliferation, reduced IGK expression led to a decrease in cell migration in acute myeloid leukemia cell lines HL-60 and NB4, whereas increased IGK expression promoted their motility. In summary, IGK is expressed in myeloblasts and mature myeloid cells from patients with non-hematopoietic neoplasms, and is involved in cell migration. These results suggest that myeloid cells-derived IgK may have a role in leukemogenesis and may serve as a novel tumor marker for monitoring minimal residual disease and developing target therapy.

  9. Runx1 Regulates Myeloid Precursor Differentiation Into Osteoclasts Without Affecting Differentiation Into Antigen Presenting or Phagocytic Cells in Both Males and Females

    Science.gov (United States)

    Paglia, David N.; Yang, Xiaochuan; Kalinowski, Judith; Jastrzebski, Sandra

    2016-01-01

    Runt-related transcription factor 1 (Runx1), a master regulator of hematopoiesis, is expressed in preosteoclasts. Previously we evaluated the bone phenotype of CD11b-Cre Runx1fl/fl mice and demonstrated enhanced osteoclasts and decreased bone mass in males. However, an assessment of the effects of Runx1 deletion in female osteoclast precursors was impossible with this model. Moreover, the role of Runx1 in myeloid cell differentiation into other lineages is unknown. Therefore, we generated LysM-Cre Runx1fl/fl mice, which delete Runx1 equally (∼80% deletion) in myeloid precursor cells from both sexes and examined the capacity of these cells to differentiate into osteoclasts and phagocytic and antigen-presenting cells. Both female and male LysM-Cre Runx1fl/fl mice had decreased trabecular bone mass (72% decrease in bone volume fraction) and increased osteoclast number (2–3 times) (P LysM-Cre did not alter the number of myeloid precursor cells in bone marrow or their ability to differentiate into phagocytizing or antigen-presenting cells. This study demonstrates that abrogation of Runx1 in multipotential myeloid precursor cells significantly and specifically enhanced the ability of receptor activator of nuclear factor-κB ligand to stimulate osteoclast formation and fusion in female and male mice without affecting other myeloid cell fates. In turn, increased osteoclast activity in LysM-Cre Runx1fl/fl mice likely contributed to a decrease in bone mass. These dramatic effects were not due to increased osteoclast precursors in the deleted mutants and argue that inhibition of Runx1 in multipotential myeloid precursor cells is important for osteoclast formation and function. PMID:27267711

  10. Galactomutarotase and other galactose-related genes are rapidly induced by retinoic acid in human myeloid cells.

    Science.gov (United States)

    Pai, Tongkun; Chen, Qiuyan; Zhang, Yao; Zolfaghari, Reza; Ross, A Catharine

    2007-12-25

    Aldose-1-epimerase (mutarotase) catalyzes the interconversion of alpha and beta hexoses, which is essential for normal carbohydrate metabolism and the production of complex oligosaccharides. Galactose mutarotase (GALM) has been well characterized at the protein level, but information is lacking on the regulation of GALM gene expression. We report herein that all-trans-retinoic acid (RA), an active metabolite of vitamin A that is known to induce myeloid lineage cell differentiation into macrophage-like cells, induces a rapid and robust regulation of GALM mRNA expression in human myeloid cells. all-trans-RA at a physiological concentration (20 nM), or Am580, a ligand selective for the nuclear retinoid receptor RARalpha, increased GALM mRNA in THP-1 cells, with significantly increased expression in 2 h, increasing further to an approximately 8-fold elevation after 6-40 h (P < 0.005). In contrast, tumor necrosis factor-alpha did not increase GALM mRNA expression, although it is capable of inducing cell differentiation. RA also increased GALM mRNA in U937 and HL-60 cells. The increase in GALM mRNA by RA was blocked by pretreating THP-1 cells with actinomycin D but not by cycloheximide. GALM protein and mutarotase activity were also increased time dependently in RA-treated THP-1 cells. In addition to GALM, several other genes in the biosynthetic pathway of galactosyl-containing complex oligosaccharides were more highly expressed in RA-treated THP-1 cells, including B4GALT5, ST3GAL3, ST6GALNAC5, and GALNAC4S-6ST. Thus, the results of this study identify RA as a significant regulator of GALM and other galactose-related genes in myeloid-monocytic cells, which could affect energy utilization and synthesis of cell-surface glycoproteins or glycolipids involved in cell motility, adhesion, and/or functional properties.

  11. Mannose-exposing myeloid leukemia cells detected by the sCAR-PPA fusion protein.

    Science.gov (United States)

    Li, Gong Chu; Li, Na; Zhang, Yan Hong; Li, Xin; Wang, Yi Gang; Liu, Xin Yuan; Qian, Wen Bin; Liu, Xiao Chuan

    2009-06-01

    Altered glycosylation may be a hallmark of malignant transformation and cancer progression. In the work described, a specific mannose-binding lectin, Pinellia pedatisecta agglutinin (PPA), was genetically fused with the extracellular domain of coxsackie-adenovirus receptor (CAR) to generate the soluble CAR (sCAR)-PPA fusion protein. The adenoviral transduction of acute myeloid leukemia (AML) cell lines Kasumi-1 and HL-60 was increased by sCAR-PPA, indicating that a fraction of AML cells exposing mannose residues was detected by PPA. However, sCAR-PPA did not increase the adenoviral infection of KG-1 cells, suggesting the mannose exposure of AML cells may be cell type specific. Furthermore, the infectious efficiency of Ad-EGFP in chronic myeloid leukemia cell line K562 was significantly increased by sCAR-PPA as well. We, herein, report that PPA recognized a fraction of myeloid leukemia cells showing mannose-exposing phenotype. The sCAR-PPA fusion protein combined with the adenoviral vector system may provide a useful tool for investigating myeloid leukemia cells exposing mannose residues and further elucidating the role of these cells in the leukemia development.

  12. Underground Adaptation to a Hostile Environment: Acute Myeloid Leukemia vs. Natural Killer Cells

    Science.gov (United States)

    Dulphy, Nicolas; Chrétien, Anne-Sophie; Khaznadar, Zena; Fauriat, Cyril; Nanbakhsh, Arash; Caignard, Anne; Chouaib, Salem; Olive, Daniel; Toubert, Antoine

    2016-01-01

    Acute myeloid leukemia (AML) is a heterogeneous group of malignancies which incidence increases with age. The disease affects the differentiation of hematopoietic stem or precursor cells in the bone marrow and can be related to abnormal cytogenetic and/or specific mutational patterns. AML blasts can be sensitive to natural killer (NK) cell antitumor response. However, NK cells are frequently defective in AML patients leading to tumor escape. NK cell defects affect not only the expression of the activating NK receptors, including the natural cytotoxicity receptors, the NK group 2, member D, and the DNAX accessory molecule-1, but also cytotoxicity and IFN-γ release. Such perturbations in NK cell physiology could be related to the adaptation of the AML to the immune pressure and more generally to patient’s clinical features. Various mechanisms are potentially involved in the inhibition of NK-cell functions in AML, including defects in the normal lymphopoiesis, reduced expression of activating receptors through cell-to-cell contacts, and production of immunosuppressive soluble agents by leukemic blasts. Therefore, the continuous cross-talk between AML and NK cells participates to the leukemia immune escape and eventually to patient’s relapse. Methods to restore or stimulate NK cells seem to be attractive strategies to treat patients once the complete remission is achieved. Moreover, our capacity in stimulating the NK cell functions could lead to the development of preemptive strategies to eliminate leukemia-initiating cells before the emergence of the disease in elderly individuals presenting preleukemic mutations in hematopoietic stem cells. PMID:27014273

  13. A New Approach Targeting Myeloid-Derived Suppressor Cells for Therapy of Mammary Carcinoma

    Science.gov (United States)

    2011-03-01

    Nat Rev Immunol 9, 162-174 (2009). 7. Marigo, I., Dolcetti, L., Serafini, P., Zanovello, P. & Bronte , V. Tumor-induced tolerance and immune...in B-cell lymphoma by expanding regulatory T cells. Cancer Res 68, 5439-5449 (2008). 10. Serafini, P., Borrello, I. & Bronte , V. Myeloid suppressor

  14. Role of Triggering Receptor Expressed on Myeloid Cells in the Activation of Innate Immunity

    Directory of Open Access Journals (Sweden)

    V. G. Matveyeva

    2011-01-01

    Full Text Available The innate immune system plays a key role in triggering a systemic inflammatory response (SIR. The triggering receptor expressed on myeloid cells (TREM-1, which is located on neutrophils and monocytes, is involved in SIR, by regulating the effector mechanisms of innate immunity. Hyperproduction of proinflammatory cytokines is a pathogenetic component of the hyperergic phase of acute systemic inflammation. The simultaneous activation of Toll-like receptors and TREM-1 increases the production of cytokines manifold. This is compensatory and adaptive, however, resulting in damage to organs and tissues during excessive production of cytokines. Key words: triggering receptor expressed on myeloid cells, Toll-like receptors, cytokines, inflammation.

  15. Mesenchymal Transition of High-Grade Breast Carcinomas Depends on Extracellular Matrix Control of Myeloid Suppressor Cell Activity

    Directory of Open Access Journals (Sweden)

    Sabina Sangaletti

    2016-09-01

    Full Text Available The extracellular matrix (ECM contributes to the biological and clinical heterogeneity of breast cancer, and different prognostic groups can be identified according to specific ECM signatures. In high-grade, but not low-grade, tumors, an ECM signature characterized by high SPARC expression (ECM3 identifies tumors with increased epithelial-to-mesenchymal transition (EMT, reduced treatment response, and poor prognosis. To better understand how this ECM3 signature is contributing to tumorigenesis, we expressed SPARC in isogenic cell lines and found that SPARC overexpression in tumor cells reduces their growth rate and induces EMT. SPARC expression also results in the formation of a highly immunosuppressive microenvironment, composed by infiltrating T regulatory cells, mast cells, and myeloid-derived suppressor cells (MDSCs. The ability of SPARC to induce EMT depended on the localization and suppressive function of myeloid cells, and inhibition of the suppressive function MDSCs by administration of aminobisphosphonates could revert EMT, rendering SPARC-overexpressing tumor cells sensitive to Doxil. We conclude that that SPARC is regulating the interplay between MDSCs and the ECM to drive the induction of EMT in tumor cells.

  16. Human breast cancer cells share antigens with the myeloid monocyte lineage.

    OpenAIRE

    F. Calvo; Martin, P M; Jabrane, N.; de Cremoux, P; Magdelenat, H.

    1987-01-01

    We have examined the expression of several myeloid cell associated antigens, some of which are involved in myelomonocyte adhesion, in seven well characterized human breast cancer cell lines, since common properties of adhesiveness and migration are found in haemopoietic cells and epithelial cancer cells. Five of these cell lines were of metastatic origin and two were derived from primary breast carcinoma. Antigenic expression was evaluated by immunofluorescence (IF), flow cytometry (FCM), rad...

  17. Mesenchymal Stem Cells (MSC Regulate Activation of Granulocyte-Like Myeloid Derived Suppressor Cells (G-MDSC in Chronic Myeloid Leukemia Patients.

    Directory of Open Access Journals (Sweden)

    Cesarina Giallongo

    Full Text Available It is well known that mesenchymal stem cells (MSC have a role in promotion of tumor growth, survival and drug-resistance in chronic myeloid leukemia (CML. Recent reports indicated that a subpopulation of myeloid cells, defined as granulocyte-like myeloid-derived suppressor cells (G-MDSC is increased in these patients. So far, the role of MSC in MDSC expansion and activation into the BM microenvironment remains unexplored. To address this question, here we use a specific experimental model in vitro, co-culturing MSC with peripheral blood mononucleated cells (PBMC from normal individuals, in order to generate MSC-educated G-MDSC. Although MSC of healthy donors (HD and CML patients were able to generate the same amount of MDSC, only CML-MSC-educated G-MDSC exhibited suppressive ability on autologous T lymphocytes. In addition, compared with HD-MSC, CML-MSC over-expressed some immunomodulatory factors including TGFβ, IL6 and IL10, that could be involved in MDSC activation. CML-MSC-educated G-MDSC expressed higher levels of ARG1, TNFα, IL1β, COX2 and IL6 than G-MDSC isolated from co-culture with HD-MSC. Our data provide evidence that CML-MSC may play a critical role in tumor microenvironment by orchestrating G-MDSC activation and regulating T lymphocytes-mediated leukemia surveillance, thus contributing to CML immune escape.

  18. Mononuclear cells in subcutaneous haemorrhage with special consideration of myeloid percursor cells.

    Science.gov (United States)

    Oehmichen, M; Windisch, A; Meissner, C

    2000-10-01

    Various hematogenous markers were used to differentiate and quantify the types of mononuclear cells present in subcutaneous haemorrhages. Fifty samples of subcutaneous bleeding with a survival time of a few minutes to more than 48 hours were studied. The various cell types were detected using the following stains: Naphthol AS-D chloracetate esterase for myeloid cells, including mast cells; (alpha1-antichymotrypsin for monocytes/macrophages; UCHL1 for T-lymphocytes; and L26 for B lymphocytes. The percentage of monocytes/macrophages was found to increase in dependence on survival time, whereas T-lymphocytes declined. Within minutes of injury neutrophilic granulocytes had emigrated into the surrounding tissue and mast cell degranulation had occurred within the haemorrhagic zone. Esterase-positive mononuclear cells, namely metamyelocytes, were detected within minutes after injury and were still present after survival times exceeding 48 hours; however, no dependence on survival time or cause of death was found. Although the increasing number of monocytes/ macrophages and T-lymphocytes was expected, the sometimes high percentage of myeloid precursor cells within the wound were surprising. Possible explanations for this phenomenon are discussed.

  19. Omega 3 fatty acids reduce myeloid progenitor cell frequency in the bone marrow of mice and promote progenitor cell differentiation

    Directory of Open Access Journals (Sweden)

    Sollars Vincent E

    2009-03-01

    Full Text Available Abstract Background Omega 3 fatty acids have been found to inhibit proliferation, induce apoptosis, and promote differentiation in various cell types. The processes of cell survival, expansion, and differentiation are of key importance in the regulation of hematopoiesis. We investigated the role of omega 3 fatty acids in controlling the frequency of various myeloid progenitor cells in the bone marrow of mice. Increased progenitor cell frequency and blocked differentiation are characteristics of hematopoietic disorders of the myeloid lineage, such as myeloproliferative diseases and myeloid leukemias. Results We found that increasing the proportion of omega 3 fatty acids relative to the proportion of omega 6 fatty acids in the diet caused increased differentiation and reduced the frequency of myeloid progenitor cells in the bone marrow of mice. Furthermore, this had no adverse effect on peripheral white blood cell counts. Conclusion Our results indicate that omega 3 fatty acids impact hematopoietic differentiation by reducing myeloid progenitor cell frequency in the bone marrow and promoting progenitor cell differentiation. Further exploration of this discovery could lead to the use of omega 3 fatty acids as a therapeutic option for patients that have various disorders of hematopoiesis.

  20. Myeloid cell-derived HIF attenuates inflammation in UUO-induced kidney injury

    Science.gov (United States)

    Kobayashi, Hanako; Gilbert, Victoria; Liu, Qingdu; Kapitsinou, Pinelopi P.; Unger, Travis L.; Rha, Jennifer; Rivella, Stefano; Schlöndorff, Detlef; Haase, Volker H.

    2012-01-01

    Renal fibrosis and inflammation are associated with hypoxia, and tissue pO2 plays a central role in modulating the progression of chronic kidney disease. Key mediators of cellular adaptation to hypoxia are hypoxia-inducible factor (HIF)-1 and -2. In the kidney they are expressed in a cell type-specific manner; to what degree activation of each homolog modulates renal fibrogenesis and inflammation has not been established. To address this issue, we used Cre-loxP recombination to activate or to delete both Hif-1 and Hif-2 either globally or cell type-specifically in myeloid cells. Global activation of Hif suppressed inflammation and fibrogenesis in mice subjected to unilateral ureteral obstruction, while activation of Hif in myeloid cells suppressed inflammation only. Suppression of inflammatory cell infiltration was associated with down-regulation of CC chemokine receptors in renal macrophages. Conversely, global deletion or myeloid-specific inactivation of Hif promoted inflammation. Furthermore, prolonged hypoxia suppressed the expression of multiple inflammatory molecules in non-injured kidneys. Collectively, we provide experimental evidence that hypoxia and/or myeloid cell-specific HIF activation attenuates renal inflammation associated with chronic kidney injury. PMID:22490864

  1. Expansion in vitro and cytotoxicity of dendritic cells from patients with chronic myeloid leukemia.

    Science.gov (United States)

    Ji, Lei; Xing, Pei-Ni; Wei, Xu-Cang; Wang, Tong; Li, Mei-Sheng; Zhang, Wang-Gang

    2005-04-01

    The study was aimed to investigate the extensive amplification and the cytotoxicity of dendritic cells (DC) derived from chronic myeloid leukemia cells. DC were cultured in two steps: firstly, extensive amplification in primary culture of CD34(+) or mononuclear cells isolated from CML patients' bone marrow and peripheral blood with rhFlt3-L and rhTPO for 7 days; secondly, inducing culture of DC with rhGM-CSF, rhTNF and rhIL-4 for 14 days. A system inducing DC directly were established for comparison. DC were identified by immunophenotype with flow cytometry, chromosome analysis by displaying G banding and electric microscopy analysis. The function of stimulating T cells proliferation and cytotoxicity of CML cells were confirmed through MTT assay. The results showed that after first extensive amplification in primary culture with rhFlt3-L and rhTPO for 7 days, CD34(+) cells had a total cell number with (77 +/- 5) fold expansion, and DC were (39 +/- 8)% of total cell respectively after induction culture of DC with rhGM-CSF, rhTNF and rhIL-4 for 14 days. Both the amplification of cell number and yield of DC were higher than the system without extensively culture (P < 0.01). Such DC could stimulate T cells to proliferate and kill leukemia cells finally. In conclusion, two-step culture method can obviously improve the cell number of DC required, that is better than inducing them directly. DC derived from CML cells induce the generation of anti-leukemia immunization.

  2. Triggering receptor expressed on myeloid cells-1: New player in antiviral immunity?

    Directory of Open Access Journals (Sweden)

    Kelsey eRoe

    2014-11-01

    Full Text Available The triggering receptor expressed on myeloid cells (TREM family of protein receptors is quickly emerging as a critical regulator of a diverse array of cellular functions including amplification of inflammation. Although the ligand(s for TREMs have not yet been fully identified, circumstantial evidence indicates that danger- and pathogen-associated molecular patterns (DAMPs and PAMPs can induce cytokine production via TREM-1 activation. The discovery of novel functions of TREMs such as regulation of T cell proliferation and activation of antigen presenting cells suggests a larger role of TREM proteins in modulation of host immune responses to microbial pathogens such as bacteria and fungi. However, the significance of TREM signaling in innate immunity to virus infections and underlying mechanisms remains largely unclear. The nature and intensity of innate immune responses, specifically production of type I Interferon and inflammatory cytokines is a crucial event in dictating recovery versus adverse outcome of virus infections. In this review, we highlight the emerging roles of TREM-1, including synergy with classical pathogen recognition receptors. Based on the literature using viral PAMPs and other infectious disease models, we further discuss how TREM-1 may influence host-virus interactions and viral pathogenesis. A deeper conceptual understanding of the mechanisms associated with pathogenic and/or protective functions of TREM-1 in antiviral immunity is essential to develop novel therapeutic strategies for the control of virus infection by modulating innate immune signaling.

  3. Myeloid-derived suppressor cells play crucial roles in the regulation of mouse collagen-induced arthritis.

    Science.gov (United States)

    Fujii, Wataru; Ashihara, Eishi; Hirai, Hideyo; Nagahara, Hidetake; Kajitani, Naoko; Fujioka, Kazuki; Murakami, Ken; Seno, Takahiro; Yamamoto, Aihiro; Ishino, Hidetaka; Kohno, Masataka; Maekawa, Taira; Kawahito, Yutaka

    2013-08-01

    Myeloid-derived suppressor cells (MDSCs) are of myeloid origin and are able to suppress T cell responses. The role of MDSCs in autoimmune diseases remains controversial, and little is known about the function of MDSCs in autoimmune arthritis. In this study, we clarify that MDSCs play crucial roles in the regulation of proinflammatory immune response in a collagen-induced arthritis (CIA) mouse model. MDSCs accumulated in the spleens of mice with CIA when arthritis severity peaked. These MDSCs inhibited the proliferation of CD4(+) T cells and their differentiation into Th17 cells in vitro. Moreover, MDSCs inhibited the production of IFN-γ, IL-2, TNF-α, and IL-6 by CD4(+) T cells in vitro, whereas they promoted the production of IL-10. Adoptive transfer of MDSCs reduced the severity of CIA in vivo, which was accompanied by a decrease in the number of CD4(+) T cells and Th17 cells in the draining lymph nodes. However, depletion of MDSCs abrogated the spontaneous improvement of CIA. In conclusion, MDSCs in CIA suppress the progression of CIA by inhibiting the proinflammatory immune response of CD4(+) T cells. These observations suggest that MDSCs play crucial roles in the regulation of autoimmune arthritis, which could be exploited in new cell-based therapies for human rheumatoid arthritis.

  4. EFFECTS OF CURCUMIN ON PROLIFERATION AND APOPTOSIS IN ACUTE MYELOID LEUKEMIA CELLS HL-60

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To investigate the curcumin killing leukemia cells in vitro,. Methods: The myeloid leukemic cell line HL-60 was studied by using cell culture, flow cytometrydetermining DNA content and TUNEL method measuring apoptotic cell percentage. Results: The data showed that curcumin selectively inhibited proliferation of acute myeloid leukemia (AML) HL-60 cell lines in a dose- and time-dependent manner. The growth inhibition rate was gradually increased and reached the peak at concentration of 25 m mol/L curcumin at 24h. The sub-G1 peak appeared after 12h treatment and was increased to 34.4% at 24h. The TUNEL method further certified that apoptotic cells reached 41% at the same phase. Conclusion: curcumin possesses obvious potent of anti-leukemia cell proliferation, which is contributed to the induction of HL-60 cells apoptosis. The concentration and action time of curcumin in vitro provide some reference for clinical use.

  5. Attenuated Toxoplasma gondii Stimulates Immunity to Pancreatic Cancer by Manipulation of Myeloid Cell Populations.

    Science.gov (United States)

    Sanders, Kiah L; Fox, Barbara A; Bzik, David J

    2015-08-01

    Suppressive myeloid cells represent a significant barrier to the generation of productive antitumor immune responses to many solid tumors. Eliminating or reprogramming suppressive myeloid cells to abrogate tumor-associated immune suppression is a promising therapeutic approach. We asked whether treatment of established aggressive disseminated pancreatic cancer with the immunotherapeutic attenuated Toxoplasma gondii vaccine strain CPS would trigger tumor-associated myeloid cells to generate therapeutic antitumor immune responses. CPS treatment significantly decreased tumor-associated macrophages and markedly increased dendritic cell infiltration of the pancreatic tumor microenvironment. Tumor-resident macrophages and dendritic cells, particularly cells actively invaded by CPS, increased expression of costimulatory molecules CD80 and CD86 and concomitantly boosted their production of IL12. CPS treatment increased CD4(+) and CD8(+) T-cell infiltration into the tumor microenvironment, activated tumor-resident T cells, and increased IFNγ production by T-cell populations. CPS treatment provided a significant therapeutic benefit in pancreatic tumor-bearing mice. This therapeutic benefit depended on IL12 and IFNγ production, MyD88 signaling, and CD8(+) T-cell populations. Although CD4(+) T cells exhibited activated effector phenotypes and produced IFNγ, CD4(+) T cells as well as natural killer cells were not required for the therapeutic benefit. In addition, CD8(+) T cells isolated from CPS-treated tumor-bearing mice produced IFNγ after re-exposure to pancreatic tumor antigen, suggesting this immunotherapeutic treatment stimulated tumor cell antigen-specific CD8(+) T-cell responses. This work highlights the potency and immunotherapeutic efficacy of CPS treatment and demonstrates the significance of targeting tumor-associated myeloid cells as a mechanism to stimulate more effective immunity to pancreatic cancer.

  6. Overcoming resistance to checkpoint blockade therapy by targeting PI3Kγ in myeloid cells.

    Science.gov (United States)

    De Henau, Olivier; Rausch, Matthew; Winkler, David; Campesato, Luis Felipe; Liu, Cailian; Cymerman, Daniel Hirschhorn; Budhu, Sadna; Ghosh, Arnab; Pink, Melissa; Tchaicha, Jeremy; Douglas, Mark; Tibbitts, Thomas; Sharma, Sujata; Proctor, Jennifer; Kosmider, Nicole; White, Kerry; Stern, Howard; Soglia, John; Adams, Julian; Palombella, Vito J; McGovern, Karen; Kutok, Jeffery L; Wolchok, Jedd D; Merghoub, Taha

    2016-11-17

    Recent clinical trials using immunotherapy have demonstrated its potential to control cancer by disinhibiting the immune system. Immune checkpoint blocking (ICB) antibodies against cytotoxic-T-lymphocyte-associated protein 4 or programmed cell death protein 1/programmed death-ligand 1 have displayed durable clinical responses in various cancers. Although these new immunotherapies have had a notable effect on cancer treatment, multiple mechanisms of immune resistance exist in tumours. Among the key mechanisms, myeloid cells have a major role in limiting effective tumour immunity. Growing evidence suggests that high infiltration of immune-suppressive myeloid cells correlates with poor prognosis and ICB resistance. These observations suggest a need for a precision medicine approach in which the design of the immunotherapeutic combination is modified on the basis of the tumour immune landscape to overcome such resistance mechanisms. Here we employ a pre-clinical mouse model system and show that resistance to ICB is directly mediated by the suppressive activity of infiltrating myeloid cells in various tumours. Furthermore, selective pharmacologic targeting of the gamma isoform of phosphoinositide 3-kinase (PI3Kγ), highly expressed in myeloid cells, restores sensitivity to ICB. We demonstrate that targeting PI3Kγ with a selective inhibitor, currently being evaluated in a phase 1 clinical trial (NCT02637531), can reshape the tumour immune microenvironment and promote cytotoxic-T-cell-mediated tumour regression without targeting cancer cells directly. Our results introduce opportunities for new combination strategies using a selective small molecule PI3Kγ inhibitor, such as IPI-549, to overcome resistance to ICB in patients with high levels of suppressive myeloid cell infiltration in tumours.

  7. Biological Therapy in Treating Patients With Advanced Myelodysplastic Syndrome, Acute or Chronic Myeloid Leukemia, or Acute Lymphoblastic Leukemia Who Are Undergoing Stem Cell Transplantation

    Science.gov (United States)

    2017-03-27

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); B-cell Adult Acute Lymphoblastic Leukemia; B-cell Childhood Acute Lymphoblastic Leukemia; Childhood Chronic Myelogenous Leukemia; Childhood Myelodysplastic Syndromes; Chronic Myelomonocytic Leukemia; Essential Thrombocythemia; Polycythemia Vera; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia; Secondary Acute Myeloid Leukemia; T-cell Adult Acute Lymphoblastic Leukemia; T-cell Childhood Acute Lymphoblastic Leukemia

  8. Myeloid-derived suppressor cells mediate tolerance induction in autoimmune disease.

    Science.gov (United States)

    Wegner, Anja; Verhagen, Johan; Wraith, David C

    2017-01-31

    In multiple sclerosis (MS) T cells aberrantly recognize self-peptides of the myelin sheath and attack the central nervous system (CNS). Antigen-specific peptide immunotherapy, which aims to restore tolerance while avoiding the use of non-specific immunosuppressive drugs, is a promising approach to combat autoimmune disease, but the cellular mechanisms behind successful therapy remain poorly understood. Myeloid-derived suppressor cells (MDSCs) have been studied intensively in the field of cancer and to a lesser extent in autoimmunity. Because of their suppressive effect on the immune system in cancer, we hypothesized that the development of MDSCs and their interaction with CD4(+) T cells could be beneficial for antigen-specific immunotherapy. Hence, changes in the quantity, phenotype and function of MDSCs during tolerance induction in our model of MS were evaluated. We reveal, for the first time, an involvement of a subset of MDSCs, known as polymorphonuclear (PMN)-MDSCs, in the process of tolerance induction. PMN-MDSCs were shown to adopt a more suppressive phenotype during peptide immunotherapy and inhibit CD4(+) T-cell proliferation in a cell-contact-dependent manner, mediated by arginase-1. Moreover, increased numbers of tolerogenic PMN-MDSCs, such as observed over the course of peptide immunotherapy, were demonstrated to provide protection from disease in a model of experimental autoimmune encephalomyelitis.

  9. Myeloid derived suppressor cells in physiological and pathological conditions: the good, the bad, and the ugly.

    Science.gov (United States)

    Serafini, Paolo

    2013-12-01

    Myeloid derived suppressor cells (MDSCs), a heterogeneous population of myeloid progenitors, are recognized as a key element in tumor escape and progression. The importance of MDSCs in human malignancies has been demonstrated in recent years, and new approaches targeting their suppressive/tolerogenic action are currently being tested in both preclinical model and clinical trials. However, emerging evidence suggests that MDSCs may play a prominent role as regulator of the physiologic, the chronic, and the pathologic immune responses. This review will focus on the biology of MDSC in light of these new findings and the possible role of this myeloid population not only in the progression of the tumor but also in its initiation.

  10. Soluble triggering receptor expressed on myeloid cells 1: a biomarker for bacterial meningitis

    NARCIS (Netherlands)

    R.M. Determann; M. Weisfelt; J. de Gans; A. van der Ende; M.J. Schultz; D. van de Beek

    2006-01-01

    Objective: To evaluate whether soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) in CSF can serve as a biomarker for the presence of bacterial meningitis and outcome in patients with this disease. Design: Retrospective study of diagnostic accuracy. Setting and patients: CSF was coll

  11. The expression of PML in chronic myeloid leukemia and effect on cell proliferation

    Institute of Scientific and Technical Information of China (English)

    吴洁

    2013-01-01

    Objective To investigate whether PML is expressed differently in chronic myeloid leukemia (CML) patients and healthy controls,then explore the effect of PML on proliferation in leukemia cell lines K562.Methods Realtime PCR was used to detect the PML expression in

  12. Myeloid derived suppressor cells-An overview of combat strategies to increase immunotherapy efficacy

    NARCIS (Netherlands)

    Draghiciu, Oana; Lubbers, Joyce; Nijman, Hans W.; Daemen, Toos

    2015-01-01

    Myeloid-derived suppressor cells (MDSCs) contribute to tumor-mediated immune escape and negatively correlate with overall survival of cancer patients. Nowadays, a variety of methods to target MDSCs are being investigated. Based on the intervention stage of MDSCs, namely development, expansion and ac

  13. Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

    Science.gov (United States)

    Evans, Vanessa A; Kumar, Nitasha; Filali, Ali; Procopio, Francesco A; Yegorov, Oleg; Goulet, Jean-Philippe; Saleh, Suha; Haddad, Elias K; da Fonseca Pereira, Candida; Ellenberg, Paula C; Sekaly, Rafick-Pierre; Cameron, Paul U; Lewin, Sharon R

    2013-01-01

    Latently infected resting CD4(+) T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+) T cells and syngeneic myeloid dendritic cells (mDC) can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+) T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+) T cells. Gene expression in non-proliferating CD4(+) T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+) T cells, which is predominantly mediated through signalling during DC-T cell contact.

  14. Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Vanessa A Evans

    Full Text Available Latently infected resting CD4(+ T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+ T cells and syngeneic myeloid dendritic cells (mDC can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+ T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+ T cells. Gene expression in non-proliferating CD4(+ T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+ T cells, which is predominantly mediated through signalling during DC-T cell contact.

  15. Blood myeloid and lymphoid dendritic cells reflect Th1/Th2 balance in sarcoidosis and extrinsic allergic alveolitis.

    Science.gov (United States)

    Buczkowski, Jarosław; Krawczyk, Paweł; Chocholska, Sylwia; Tabarkiewicz, Jacek; Kieszko, Robert; Michnar, Marek; Milanowski, Janusz; Roliński, Jacek

    2003-01-01

    Dendritic cells play a specific regulatory role in the immune system. In this paper, the significance of myeloid and lymphoid dendritic cells in sarcoidosis and extrinsic allergic alveolitis (EAA) was evaluated. Myeloid dendritic cells are connected with Th1 type of immunological response, whereas lymphoid ones--with Th2 type. The latest findings indicate that both diseases are characterized by serious disturbances of Th1/Th2 response to Th1 dominance. Our studies seem to confirm these suggestions. In the peripheral blood of patients with sarcoidosis as well as with EAA, myeloid dendritic cells outnumbered lymphoid ones.

  16. Cell-extrinsic effects of tumor ER stress imprint myeloid dendritic cells and impair CD8⁺ T cell priming.

    Science.gov (United States)

    Mahadevan, Navin R; Anufreichik, Veronika; Rodvold, Jeffrey J; Chiu, Kevin T; Sepulveda, Homero; Zanetti, Maurizio

    2012-01-01

    Tumor-infiltrating myeloid cells, such as dendritic cells (BMDC), are key regulators of tumor growth. However, the tumor-derived signals polarizing BMDC to a phenotype that subverts cell-mediated anti-tumor immunity have yet to be fully elucidated. Addressing this unresolved problem we show that the tumor unfolded protein response (UPR) can function in a cell-extrinsic manner via the transmission of ER stress (TERS) to BMDC. TERS-imprinted BMDC upregulate the production of pro-inflammatory, tumorigenic cytokines but also the immunosuppressive enzyme arginase. Importantly, they downregulate cross-presentation of high-affinity antigen and fail to effectively cross-prime CD8(+) T cells, causing T cell activation without proliferation and similarly dominantly suppress cross-priming by bystander BMDC. Lastly, TERS-imprinted BMDC facilitate tumor growth in vivo with fewer tumor-infiltrating CD8(+) T cells. In sum, we demonstrate that tumor-borne ER stress imprints ab initio BMDC to a phenotype that recapitulates several of the inflammatory/suppressive characteristics ascribed to tumor-infiltrating myeloid cells, highlighting the tumor UPR as a critical controller of anti-tumor immunity and a new target for immune modulation in cancer.

  17. Cell-extrinsic effects of tumor ER stress imprint myeloid dendritic cells and impair CD8⁺ T cell priming.

    Directory of Open Access Journals (Sweden)

    Navin R Mahadevan

    Full Text Available Tumor-infiltrating myeloid cells, such as dendritic cells (BMDC, are key regulators of tumor growth. However, the tumor-derived signals polarizing BMDC to a phenotype that subverts cell-mediated anti-tumor immunity have yet to be fully elucidated. Addressing this unresolved problem we show that the tumor unfolded protein response (UPR can function in a cell-extrinsic manner via the transmission of ER stress (TERS to BMDC. TERS-imprinted BMDC upregulate the production of pro-inflammatory, tumorigenic cytokines but also the immunosuppressive enzyme arginase. Importantly, they downregulate cross-presentation of high-affinity antigen and fail to effectively cross-prime CD8(+ T cells, causing T cell activation without proliferation and similarly dominantly suppress cross-priming by bystander BMDC. Lastly, TERS-imprinted BMDC facilitate tumor growth in vivo with fewer tumor-infiltrating CD8(+ T cells. In sum, we demonstrate that tumor-borne ER stress imprints ab initio BMDC to a phenotype that recapitulates several of the inflammatory/suppressive characteristics ascribed to tumor-infiltrating myeloid cells, highlighting the tumor UPR as a critical controller of anti-tumor immunity and a new target for immune modulation in cancer.

  18. Modeling of C/EBPalpha mutant acute myeloid leukemia reveals a common expression signature of committed myeloid leukemia-initiating cells

    DEFF Research Database (Denmark)

    Kirstetter, Peggy; Schuster, Mikkel B; Bereshchenko, Oksana

    2008-01-01

    Mutations in the CEBPA gene are present in 7%-10% of human patients with acute myeloid leukemia (AML). However, no genetic models exist that demonstrate their etiological relevance. To mimic the most common mutations affecting CEBPA-that is, those leading to loss of the 42 kDa C/EBPalpha isoform (p...... penetrance. p42-deficient leukemia could be transferred by a Mac1+c-Kit+ population that gave rise only to myeloid cells in recipient mice. Expression profiling of this population against normal Mac1+c-Kit+ progenitors revealed a signature shared with MLL-AF9-transformed AML....

  19. Myeloid-derived suppressor cells modulate immune responses independently of NADPH oxidase in the ovarian tumor microenvironment in mice.

    Directory of Open Access Journals (Sweden)

    Heidi E Godoy

    Full Text Available The phagocyte NADPH oxidase generates superoxide anion and downstream reactive oxidant intermediates in response to infectious threat, and is a critical mediator of antimicrobial host defense and inflammatory responses. Myeloid-derived suppressor cells (MDSCs are a heterogeneous population of immature myeloid cells that are recruited by cancer cells, accumulate locally and systemically in advanced cancer, and can abrogate anti-tumor immunity. Prior studies have implicated the phagocyte NADPH oxidase as being an important component promoting MDSC accumulation and immunosuppression in cancer. We therefore used engineered NADPH oxidase-deficient (p47 (phox-/- mice to delineate the role of this enzyme complex in MDSC accumulation and function in a syngeneic mouse model of epithelial ovarian cancer. We found that the presence of NADPH oxidase did not affect tumor progression. The accumulation of MDSCs locally and systemically was similar in tumor-bearing wild-type (WT and p47 (phox-/- mice. Although MDSCs from tumor-bearing WT mice had functional NADPH oxidase, the suppressive effect of MDSCs on ex vivo stimulated T cell proliferation was NADPH oxidase-independent. In contrast to other tumor-bearing mouse models, our results show that MDSC accumulation and immunosuppression in syngeneic epithelial ovarian cancer is NADPH oxidase-independent. We speculate that factors inherent to the tumor, tumor microenvironment, or both determine the specific requirement for NADPH oxidase in MDSC accumulation and function.

  20. Establishment of induced pluripotent stem cells from aged mice using bone marrow-derived myeloid cells

    Institute of Scientific and Technical Information of China (English)

    Zhao Cheng; Sachiko Ito; Naomi Nishio; Hengyi Xiao; Rong Zhang; Haruhiko Suzuki; Yayoi Okawa; Toyoaki Murohara; Ken-ichi Isobe

    2011-01-01

    If induced pluripotent stem (iPS) cells are to be used to treat damaged tissues or repair organs in elderly patients, it will be necessaryto establish iPS cells from their tissues. To determine the feasibility of using this technology with elderly patients, we asked if itwas indeed possible to establish iPS cells from the bone marrow (BM) of aged mice. BM cells from aged C57BL/6 mice carrying thegreen fluorescence protein (GFP) gene were cultured with granulocyte macrophage-colony stimulating factor (GM-CSF) for 4 days.Four factors (Oct3/4, Sox2, Klf4 and c-Myc) were introduced into the BM-derived myeloid (BM-M) cells. The efficiency of generating iPS cells from aged BM cultured in GM-CSF was low. However, we succeeded in obtaining BM-M-iPS cells from aged C57BL/6 mice,which carried GFP. Our BM-M-iPS cells expressed SSEA-1 and Pou5f1 and were positive for alkaline phosphatase staining. The iPScells did make teratoma with three germ layers following injection into syngeneic C57BL/6 mice, and can be differentiated to threegerm layers in vitro. By co-culturing with OP9, the BM-M-iPS cells can be differentiated to the myeloid lineage. The differentiated BM-M-iPS cells proliferated well in the presence of GM-CSF, and lost expression of Nanog and Pou5f1, at least in part, due to methylation of their promoters. On the contrary, Tnf and Il1b gene expression was upregulated and their promoters were hypornethylated.

  1. HEBAlt enhances the T-cell potential of fetal myeloid-biased precursors.

    Science.gov (United States)

    Braunstein, Marsela; Rajkumar, Paula; Claus, Carol L; Vaccarelli, Giovanna; Moore, Amanda J; Wang, Duncheng; Anderson, Michele K

    2010-12-01

    Hematopoiesis is controlled by the interplay between transcription factors and environmental signals. One of the primary determinants of the T-lineage choice is Delta-like (DL)-Notch signaling, which promotes T-cell development and inhibits B-cell development. We have found that the transcription factor HEBAlt is up-regulated in early hematopoietic precursors in response to DL-Notch signaling and that it can promote early T-cell development. Here, we identified a population of lineage-negative Sca-1⁻c-kit(+) (LK) cells in the mouse fetal liver that rapidly gave rise to myeloid cells and B cells but exhibited very little T-cell potential. However, forced expression of HEBAlt in these precursors restored their ability to develop into T cells. We also showed that Ikaros and Notch1 are up-regulated in response to HEBAlt over-expression and that activated Notch1 enhances the ability of LK cells to enter the T-cell lineage. Furthermore, the myeloid transcription factor C/EBPα is down-regulated in response to HEBAlt. We therefore propose that HEBAlt plays a role in the network that enforces the T-lineage fate and limits myeloid fate during hematopoiesis.

  2. Identification and targeting leukemia stem cells: The path to the cure for acute myeloid leukemia

    Institute of Scientific and Technical Information of China (English)

    Jianbiao; Zhou; Wee-Joo; Chng

    2014-01-01

    Accumulating evidence support the notion that acute myeloid leukemia(AML) is organized in a hierarchical system, originating from a special proportion of leukemia stem cells(LSC). Similar to their normal counterpart, hematopoietic stem cells(HSC), LSC possess selfrenewal capacity and are responsible for the continued growth and proliferation of the bulk of leukemia cells in the blood and bone marrow. It is believed that LSC are also the root cause for the treatment failure and relapse of AML because LSC are often resistant to chemotherapy. In the past decade, we have made significant advancement in identification and understanding the molecular biology of LSC, but it remains a daunting task to specifically targeting LSC, while sparing normalHSC. In this review, we will first provide a historical overview of the discovery of LSC, followed by a summary of identification and separation of LSC by either cell surface markers or functional assays. Next, the review will focus on the current, various strategies for eradicating LSC. Finally, we will highlight future directions and challenges ahead of our ultimate goal for the cure of AML by targeting LSC.

  3. The potassium channel Ether à go-go is a novel prognostic factor with functional relevance in acute myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Stühmer Walter

    2010-01-01

    Full Text Available Abstract Background The voltage-gated potassium channel hEag1 (KV10.1 has been related to cancer biology. The physiological expression of the human channel is restricted to the brain but it is frequently and abundantly expressed in many solid tumors, thereby making it a promising target for a specific diagnosis and therapy. Because chronic lymphatic leukemia has been described not to express hEag1, it has been assumed that the channel is not expressed in hematopoietic neoplasms in general. Results Here we show that this assumption is not correct, because the channel is up-regulated in myelodysplastic syndromes, chronic myeloid leukemia and almost half of the tested acute myeloid leukemias in a subtype-dependent fashion. Most interestingly, channel expression strongly correlated with increasing age, higher relapse rates and a significantly shorter overall survival. Multivariate Cox regression analysis revealed hEag1 expression levels in AML as an independent predictive factor for reduced disease-free and overall survival; such an association had not been reported before. As a functional correlate, specific hEag1 blockade inhibited the proliferation and migration of several AML cell lines and primary cultured AML cells in vitro. Conclusion Our observations implicate hEag1 as novel target for diagnostic, prognostic and/or therapeutic approaches in AML.

  4. Myeloid Dysregulation in a Human Induced Pluripotent Stem Cell Model of PTPN11-Associated Juvenile Myelomonocytic Leukemia

    Directory of Open Access Journals (Sweden)

    Sonia Mulero-Navarro

    2015-10-01

    Full Text Available Somatic PTPN11 mutations cause juvenile myelomonocytic leukemia (JMML. Germline PTPN11 defects cause Noonan syndrome (NS, and specific inherited mutations cause NS/JMML. Here, we report that hematopoietic cells differentiated from human induced pluripotent stem cells (hiPSCs harboring NS/JMML-causing PTPN11 mutations recapitulated JMML features. hiPSC-derived NS/JMML myeloid cells exhibited increased signaling through STAT5 and upregulation of miR-223 and miR-15a. Similarly, miR-223 and miR-15a were upregulated in 11/19 JMML bone marrow mononuclear cells harboring PTPN11 mutations, but not those without PTPN11 defects. Reducing miR-223’s function in NS/JMML hiPSCs normalized myelogenesis. MicroRNA target gene expression levels were reduced in hiPSC-derived myeloid cells as well as in JMML cells with PTPN11 mutations. Thus, studying an inherited human cancer syndrome with hiPSCs illuminated early oncogenesis prior to the accumulation of secondary genomic alterations, enabling us to discover microRNA dysregulation, establishing a genotype-phenotype association for JMML and providing therapeutic targets.

  5. GATA Factor-Dependent Positive-Feedback Circuit in Acute Myeloid Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Koichi R. Katsumura

    2016-08-01

    Full Text Available The master regulatory transcription factor GATA-2 triggers hematopoietic stem and progenitor cell generation. GATA2 haploinsufficiency is implicated in myelodysplastic syndrome (MDS and acute myeloid leukemia (AML, and GATA2 overexpression portends a poor prognosis for AML. However, the constituents of the GATA-2-dependent genetic network mediating pathogenesis are unknown. We described a p38-dependent mechanism that phosphorylates GATA-2 and increases GATA-2 target gene activation. We demonstrate that this mechanism establishes a growth-promoting chemokine/cytokine circuit in AML cells. p38/ERK-dependent GATA-2 phosphorylation facilitated positive autoregulation of GATA2 transcription and expression of target genes, including IL1B and CXCL2. IL-1β and CXCL2 enhanced GATA-2 phosphorylation, which increased GATA-2-mediated transcriptional activation. p38/ERK-GATA-2 stimulated AML cell proliferation via CXCL2 induction. As GATA2 mRNA correlated with IL1B and CXCL2 mRNAs in AML-M5 and high expression of these genes predicted poor prognosis of cytogenetically normal AML, we propose that the circuit is functionally important in specific AML contexts.

  6. Analysis of splenic Gr-1int immature myeloid cells in tumor-bearing mice.

    Science.gov (United States)

    Yamamoto, Yoshiko; Ishigaki, Hirohito; Ishida, Hideaki; Itoh, Yasushi; Noda, Yoichi; Ogasawara, Kazumasa

    2008-01-01

    It is known that the number of ImC, expressing myeloid markers, CD11b and Gr-1, increase with tumor growth and ImC play a role in the escape of tumor cells from immunosurveillance in tumor-bearing mice and cancer patients. However, the mechanisms by which ImC suppress immune responses in tumor-bearing mice have not been completely elucidated. In the present study, we investigated the function of splenic ImC freshly isolated from tumor-bearing mice and splenic ImC differentiated in vitro by GM-CSF. Freshly isolated splenic ImC were divided into two groups depending on Gr-1 expression, Gr-1 high (Gr-1hi) and intermediate (Gr-1int). Freshly isolated splenic Gr-1int ImC, but not Gr-1hi ImC, from tumor-bearing mice reduced production of IFN-gamma in CD8+ T cells, but neither splenic Gr-1int ImC nor Gr-1hi ImC isolated from naive mice did. Both Gr-1int and Gr-1hi ImC differentiated in vitro by GM-CSF inhibited production of IFN-gamma in both CD8+ and CD4+ T cells. In addition, the differentiated Gr-1int ImC, one-third of which were CD11c+F4/80+ cells, and their culture supernatants suppressed proliferative responses of T cells stimulated by CD3 ligation, but the differentiated Gr-1hi ImC and their culture supernatants did not. These results suggest that Gr-1int ImC are altered to immune-suppressive cells in tumor circumstances and that they are differentiated by GM-CSF progressively into CD11c+F4/80+ cells with further suppressive activity against T cells.

  7. Requiem: a novel zinc finger gene essential for apoptosis in myeloid cells.

    Science.gov (United States)

    Gabig, T G; Mantel, P L; Rosli, R; Crean, C D

    1994-11-25

    To identify genes mediating programmed cell death triggered by interleukin 3 (IL-3)-deprivation of myeloid cells, the IL-3-dependent murine myeloid cell line FDCP-1 was used to screen a mammalian cell expression library for cDNAs that would promote survival following withdrawal of IL-3. A unique 892-base pair cDNA was cloned that prevented the programmed cell death response following IL-3 deprivation by causing antisense suppression of an endogenous 2.4-kilobase (kb) mRNA. A 2.3-kb cDNA containing the identical 892-base pair over-lapping sequence was cloned that encoded a deduced 371-amino acid protein containing a single Kruppel-type zinc finger and a cluster of 4 cysteine/histidine-rich repeats resembling atypical zinc fingers. The 2.4-kb mRNA was found to be ubiquitously expressed in murine tissues and its abundance in FDCP-1 cells was not altered in response to IL-3 deprivation. Since expression of this 2.4-kb mRNA was a prerequisite for the apoptosis response following IL-3 deprivation, the gene encoding it was named requiem. Requiem is likely to encode a transcription factor required for the apoptosis response following survival factor withdrawal from myeloid cells.

  8. Caffeine affects the biological responses of human hematopoietic cells of myeloid lineage via downregulation of the mTOR pathway and xanthine oxidase activity

    Science.gov (United States)

    Abooali, Maryam; Yasinska, Inna M.; Casely-Hayford, Maxwell A.; Berger, Steffen M.; Fasler-Kan, Elizaveta; Sumbayev, Vadim V.

    2015-01-01

    Correction of human myeloid cell function is crucial for the prevention of inflammatory and allergic reactions as well as leukaemia progression. Caffeine, a naturally occurring food component, is known to display anti-inflammatory effects which have previously been ascribed largely to its inhibitory actions on phosphodiesterase. However, more recent studies suggest an additional role in affecting the activity of the mammalian target of rapamycin (mTOR), a master regulator of myeloid cell translational pathways, although detailed molecular events underlying its mode of action have not been elucidated. Here, we report the cellular uptake of caffeine, without metabolisation, by healthy and malignant hematopoietic myeloid cells including monocytes, basophils and primary acute myeloid leukaemia mononuclear blasts. Unmodified caffeine downregulated mTOR signalling, which affected glycolysis and the release of pro-inflammatory/pro-angiogenic cytokines as well as other inflammatory mediators. In monocytes, the effects of caffeine were potentiated by its ability to inhibit xanthine oxidase, an enzyme which plays a central role in human purine catabolism by generating uric acid. In basophils, caffeine also increased intracellular cyclic adenosine monophosphate (cAMP) levels which further enhanced its inhibitory action on mTOR. These results demonstrate an important mode of pharmacological action of caffeine with potentially wide-ranging therapeutic impact for treating non-infectious disorders of the human immune system, where it could be applied directly to inflammatory cells. PMID:26384306

  9. Deregulated expression of Cdc6 as BCR/ABL-dependent survival factor in chronic myeloid leukemia cells.

    Science.gov (United States)

    Zhang, Jia-Hua; He, Yan-Li; Zhu, Rui; Du, Wen; Xiao, Jun-Hua

    2017-06-01

    Chronic myeloid leukemia is characterized by the presence of the reciprocal translocation t(9;22) and the BCR/ABL oncogene. The BCR/ABL oncogene activates multiple signaling pathways and involves the dysregulation of oncogenes during the progression of chronic myeloid leukemia. The cell division cycle protein 6, an essential regulator of DNA replication, is elevated in some human cancer cells. However, the expression of cell division cycle protein 6 in chronic myeloid leukemia and the underlying regulatory mechanism remain to be elucidated. In this study, our data showed that cell division cycle protein 6 expression was significantly upregulated in primary chronic myeloid leukemia cells and the chronic myeloid leukemia cell line K562 cells, as compared to the normal bone marrow mononuclear cells. BCR/ABL kinase inhibitor STI571 or BCR/ABL small interfering RNA could significantly downregulate cell division cycle protein 6 messenger RNA expression in K562 cells. Moreover, phosphoinositide 3-kinase/AKT pathway inhibitor LY294002 and Janus kinase/signal transducer and activator of transcription pathway inhibitor AG490 could downregulate cell division cycle protein 6 expression in K562 cells, but not RAS/mitogen-activated protein kinase pathway inhibitor PD98059 had such effect. Cell division cycle protein 6 gene silencing by small interfering RNA effectively resulted in decrease of proliferation, increase of apoptosis, and arrest of cell cycle in K562 cells. These findings have demonstrated that cell division cycle protein 6 overexpression may contribute to the high proliferation and low apoptosis in chronic myeloid leukemia cells and can be regulated by BCR/ABL signal transduction through downstream phosphoinositide 3-kinase/Akt and Janus kinase/signal transducer and activator of transcription pathways, suggesting cell division cycle protein 6 as a potential therapeutic target in chronic myeloid leukemia.

  10. Immunophenotypic, cytogenetic, and mutational characterization of cell lines derived from myelodysplastic syndrome patients after progression to acute myeloid leukemia.

    Science.gov (United States)

    Palau, Anna; Mallo, Mar; Palomo, Laura; Rodríguez-Hernández, Ines; Diesch, Jeannine; Campos, Diana; Granada, Isabel; Juncà, Jordi; Drexler, Hans G; Solé, Francesc; Buschbeck, Marcus

    2017-03-01

    Leukemia cell lines have been widely used in the hematology field to unravel mechanistic insights and to test new therapeutic strategies. Myelodysplastic syndromes (MDS) comprise a heterogeneous group of diseases that are characterized by ineffective hematopoiesis and frequent progress to acute myeloid leukemia (AML). A few cell lines have been established from MDS patients after progression to AML but their characterization is incomplete. Here we provide a detailed description of the immunophenotypic profile of the MDS-derived cell lines SKK-1, SKM-1, F-36P; and MOLM-13. Specifically, we analyzed a comprehensive panel of markers that are currently applied in the diagnostic routine for myeloid disorders. To provide high-resolution genetic data comprising copy number alterations and losses of heterozygosity we performed whole genome single nucleotide polymorphism-based arrays and included the cell line OHN-GM that harbors the frequent chromosome arm 5q deletion. Furthermore, we assessed the mutational status of 83 disease-relevant genes. Our results provide a resource to the MDS and AML field that allows researchers to choose the best-matching cell line for their functional studies. © 2016 Wiley Periodicals, Inc.

  11. CD33-specific chimeric antigen receptor T cells exhibit potent preclinical activity against human acute myeloid leukemia.

    Science.gov (United States)

    Kenderian, S S; Ruella, M; Shestova, O; Klichinsky, M; Aikawa, V; Morrissette, J J D; Scholler, J; Song, D; Porter, D L; Carroll, M; June, C H; Gill, S

    2015-08-01

    Patients with chemo-refractory acute myeloid leukemia (AML) have a dismal prognosis. Chimeric antigen receptor T (CART) cell therapy has produced exciting results in CD19+ malignancies and may overcome many of the limitations of conventional leukemia therapies. We developed CART cells to target CD33 (CART33) using the anti-CD33 single chain variable fragment used in gemtuzumab ozogamicin (clone My96) and tested the activity and toxicity of these cells. CART33 exhibited significant effector functions in vitro and resulted in eradication of leukemia and prolonged survival in AML xenografts. CART33 also resulted in human lineage cytopenias and reduction of myeloid progenitors in xenograft models of hematopoietic toxicity, suggesting that permanently expressed CD33-specific CART cells would have unacceptable toxicity. To enhance the viability of CART33 as an option for AML, we designed a transiently expressed mRNA anti-CD33 CAR. Gene transfer was carried out by electroporation into T cells and resulted in high-level expression with potent but self-limited activity against AML. Thus our preclinical studies show potent activity of CART33 and indicate that transient expression of anti-CD33 CAR by RNA modification could be used in patients to avoid long-term myelosuppression. CART33 therapy could be used alone or as part of a preparative regimen prior to allogeneic transplantation in refractory AML.

  12. Drug screen in patient cells suggests quinacrine to be repositioned for treatment of acute myeloid leukemia

    OpenAIRE

    Eriksson, Anna; Österroos, Albin; Hassan, Sadia Bashir; Gullbo, Joachim; Rickardson, Linda; Jarvius, Malin; Nygren, Peter; Fryknäs, Mårten; Höglund, Martin; Larsson, Rolf

    2015-01-01

    To find drugs suitable for repositioning for use against leukemia, samples from patients with chronic lymphocytic, acute myeloid and lymphocytic leukemias as well as peripheral blood mononuclear cells (PBMC) were tested in response to 1266 compounds from the LOPAC1280 library (Sigma). Twenty-five compounds were defined as hits with activity in all leukemia subgroups (<50% cell survival compared with control) at 10 mu M drug concentration. Only one of these compounds, quinacrine, showed low...

  13. Identification of myeloid derived suppressor cells in the peripheral blood of tumor bearing dogs

    OpenAIRE

    Sherger Matthew; Kisseberth William; London Cheryl; Olivo-Marston Susan; Papenfuss Tracey L

    2012-01-01

    Abstract Background Myeloid derived suppressor cells (MDSCs) are a recently described population of immune cells that significantly contribute to the immunosuppression seen in cancer patients. MDSCs are one of the most important factors that limit the efficacy of cancer immunotherapy (e.g. cancer vaccines) and MDSC levels are increased in cancer in multiple species. Identifying and targeting MDSCs is actively being investigated in the field of human oncology and is increasingly being investig...

  14. Induction in myeloid leukemic cells of genes that are expressed in different normal tissues

    OpenAIRE

    2005-01-01

    Using DNA microarray and cluster analysis of expressed genes in a cloned line (M1-t-p53) of myeloid leukemic cells, we have analyzed the expression of genes that are preferentially expressed in different normal tissues. Clustering of 547 highly expressed genes in these leukemic cells showed 38 genes preferentially expressed in normal hematopoietic tissues and 122 other genes preferentially expressed in different normal non-hematopoietic tissues including neuronal tissues, muscle, liver and te...

  15. Successful hematopoietic cell transplantation in a patient with X-linked agammaglobulinemia and acute myeloid leukemia.

    Science.gov (United States)

    Abu-Arja, Rolla F; Chernin, Leah R; Abusin, Ghada; Auletta, Jeffery; Cabral, Linda; Egler, Rachel; Ochs, Hans D; Torgerson, Troy R; Lopez-Guisa, Jesus; Hostoffer, Robert W; Tcheurekdjian, Haig; Cooke, Kenneth R

    2015-09-01

    X-linked agammaglobulinemia (XLA) is a primary immunodeficiency characterized by marked reduction in all classes of serum immunoglobulins and the near absence of mature CD19(+) B-cells. Although malignancy has been observed in patients with XLA, we present the first reported case of acute myeloid leukemia (AML) in a patient with XLA. We also demonstrate the complete correction of the XLA phenotype following allogeneic hematopoietic cell transplantation for treatment of the patient's leukemia.

  16. Redefining Langerhans Cell Histiocytosis as a Myeloid Dysplasia and Identifying B | Division of Cancer Prevention

    Science.gov (United States)

    DESCRIPTION (provided by applicant): Redefining Langerhans Cell Histiocytosis as a Myeloid Dysplasia and Identifying Biomarkers for Early Detection and Risk Assessment. This application addresses Program Announcement PA-09-197: Biomarkers for Early Detection of Hematopoietic Malignancies (R01). The overall aim of this project is to identify novel biomarkers that may be used to diagnose and treat patients with Langerhans Cell Histiocytosis (LCH). LCH occurs with similar frequency as other rare malignancies including Hodgkin's lymphoma and AML. |

  17. [Key molecular mechanisms associated with cell malignant transformation in acute myeloid leukemia].

    Science.gov (United States)

    Orlova, N N; Lebedev, T D; Spirin, P V; Prassolov, V S

    2016-01-01

    Cancer, along with cardiovascular disorders, is one of the most important problems of healthcare. Pathologies of the hematopoietic system are the most prevalent in patients under 30 years of age, including acute myeloid leukemia (AML), which is widespread and difficult to treat. The review considers the mechanisms that play a significant role in AML cell malignant transformation and shows the contributions of certain genes to both remission and resistance of AML cells to various treatments.

  18. Identification of myeloid derived suppressor cells in dogs with naturally occurring cancer.

    Science.gov (United States)

    Goulart, Michelle R; Pluhar, G Elizabeth; Ohlfest, John R

    2012-01-01

    Dogs with naturally occurring cancer represent an important large animal model for drug development and testing novel immunotherapies. However, poorly defined immunophenotypes of canine leukocytes have limited the study of tumor immunology in dogs. The accumulation of myeloid derived suppressor cells (MDSCs) is known to be a key mechanism of immune suppression in tumor-bearing mice and in human patients. We sought to identify MDSCs in the blood of dogs with cancer. Peripheral blood mononuclear cells (PBMCs) from dogs with advanced or early stage cancer and from age-matched healthy controls were analyzed by flow cytometry and microscopy. Suppressive function was tested in T cell proliferation and cytokine elaboration assays. Semi-quantitative RT-PCR was used to identify potential mechanisms responsible for immunosuppression. PBMCs from dogs with advanced or metastatic cancer exhibited a significantly higher percentage of CD11b(+)CD14(-)MHCII(-) cells compared to dogs diagnosed with early stage non-metastatic tumors and healthy dogs. These CD11b(+) CD14(-)MHCII(-) cells constitute a subpopulation of activated granulocytes that co-purify with PBMCs, display polymorphonuclear granulocyte morphology, and demonstrate a potent ability to suppress proliferation and IFN-γ production in T cells from normal and tumor-bearing donors. Furthermore, these cells expressed hallmark suppressive factors of human MDSC including ARG1, iNOS2, TGF-β and IL-10. In summary our data demonstrate that MDSCs accumulate in the blood of dogs with advanced cancer and can be measured using this three-marker immunophenotype, thereby enabling prospective studies that can monitor MDSC burden.

  19. Systemic RNAi-mediated Gene Silencing in Nonhuman Primate and Rodent Myeloid Cells

    Directory of Open Access Journals (Sweden)

    Tatiana I Novobrantseva

    2012-01-01

    Full Text Available Leukocytes are central regulators of inflammation and the target cells of therapies for key diseases, including autoimmune, cardiovascular, and malignant disorders. Efficient in vivo delivery of small interfering RNA (siRNA to immune cells could thus enable novel treatment strategies with broad applicability. In this report, we develop systemic delivery methods of siRNA encapsulated in lipid nanoparticles (LNP for durable and potent in vivo RNA interference (RNAi-mediated silencing in myeloid cells. This work provides the first demonstration of siRNA-mediated silencing in myeloid cell types of nonhuman primates (NHPs and establishes the feasibility of targeting multiple gene targets in rodent myeloid cells. The therapeutic potential of these formulations was demonstrated using siRNA targeting tumor necrosis factor-α (TNFα which induced substantial attenuation of disease progression comparable to a potent antibody treatment in a mouse model of rheumatoid arthritis (RA. In summary, we demonstrate a broadly applicable and therapeutically relevant platform for silencing disease genes in immune cells.

  20. Systemic RNAi-mediated Gene Silencing in Nonhuman Primate and Rodent Myeloid Cells

    Science.gov (United States)

    Novobrantseva, Tatiana I; Borodovsky, Anna; Wong, Jamie; Klebanov, Boris; Zafari, Mohammad; Yucius, Kristina; Querbes, William; Ge, Pei; Ruda, Vera M; Milstein, Stuart; Speciner, Lauren; Duncan, Rick; Barros, Scott; Basha, Genc; Cullis, Pieter; Akinc, Akin; Donahoe, Jessica S; Narayanannair Jayaprakash, K; Jayaraman, Muthusamy; Bogorad, Roman L; Love, Kevin; Whitehead, Katie; Levins, Chris; Manoharan, Muthiah; Swirski, Filip K; Weissleder, Ralph; Langer, Robert; Anderson, Daniel G; de Fougerolles, Antonin; Nahrendorf, Matthias; Koteliansky, Victor

    2012-01-01

    Leukocytes are central regulators of inflammation and the target cells of therapies for key diseases, including autoimmune, cardiovascular, and malignant disorders. Efficient in vivo delivery of small interfering RNA (siRNA) to immune cells could thus enable novel treatment strategies with broad applicability. In this report, we develop systemic delivery methods of siRNA encapsulated in lipid nanoparticles (LNP) for durable and potent in vivo RNA interference (RNAi)-mediated silencing in myeloid cells. This work provides the first demonstration of siRNA-mediated silencing in myeloid cell types of nonhuman primates (NHPs) and establishes the feasibility of targeting multiple gene targets in rodent myeloid cells. The therapeutic potential of these formulations was demonstrated using siRNA targeting tumor necrosis factor-α (TNFα) which induced substantial attenuation of disease progression comparable to a potent antibody treatment in a mouse model of rheumatoid arthritis (RA). In summary, we demonstrate a broadly applicable and therapeutically relevant platform for silencing disease genes in immune cells. PMID:23344621

  1. Targeting myeloid cells to the brain using non-myeloablative conditioning.

    Directory of Open Access Journals (Sweden)

    Chotima Böttcher

    Full Text Available Bone marrow-derived cells (BMDCs are able to colonize the central nervous system (CNS at sites of damage. This ability makes BMDCs an ideal cellular vehicle for transferring therapeutic genes/molecules to the CNS. However, conditioning is required for bone marrow-derived myeloid cells to engraft in the brain, which so far has been achieved by total body irradiation (TBI and by chemotherapy (e.g. busulfan treatment. Unfortunately, both regimens massively disturb the host's hematopoietic compartment. Here, we established a conditioning protocol to target myeloid cells to sites of brain damage in mice using non-myeloablative focal head irradiation (HI. This treatment was associated with comparatively low inflammatory responses in the CNS despite cranial radiation doses which are identical to TBI, as revealed by gene expression analysis of cytokines/chemokines such as CCL2, CXCL10, TNF-α and CCL5. HI prior to bone marrow transplantation resulted in much lower levels of blood chimerism defined as the percentage of donor-derived cells in peripheral blood ( 95% or busulfan treatment (> 50%. Nevertheless, HI effectively recruited myeloid cells to the area of motoneuron degeneration in the brainstem within 7 days after facial nerve axotomy. In contrast, no donor-derived cells were detected in the lesioned facial nucleus of busulfan-treated animals up to 2 weeks after transplantation. Our findings suggest that myeloid cells can be targeted to sites of brain damage even in the presence of very low levels of peripheral blood chimerism. We established a novel non-myeloablative conditioning protocol with minimal disturbance of the host's hematopoietic system for targeting BMDCs specifically to areas of pathology in the brain.

  2. New insights into myeloid-derived suppressor cells and their roles in feto-maternal immune cross-talk.

    Science.gov (United States)

    Zhao, Ai-Min; Xu, Hai-Jing; Kang, Xiao-Min; Zhao, Ai-Min; Lu, Li-Ming

    2016-02-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of myeloid cells that suppress both innate and adaptive immune responses through multiple mechanisms. In recent years, much of our knowledge of the function of MDSCs has come from cancer studies. However, a few recent advances have begun to characterize MDSCs in feto-maternal immune cross-talk. The microenvironment at the fetal-maternal interface is a complex milieu of trophoblasts and maternally-derived cells, which are biased to tolerogenic and Th2-type responses. Current data reveal that MDSCs accumulate at the fetal-maternal interface in healthy pregnancies. Yet, little is known about how MDSCs develop and why the response of MDSCs is heavily granulocytic. In this review, we discuss recent findings on the molecular mechanisms that regulate the expansion and function of MDSCs, in addition to various roles of MDSCs implicated in the modulation of feto-maternal immune cross-talk. Understanding the roles of MDSCs in inducing maternal-fetal tolerance, which is compromised in patients suffering from pregnancy complications, including preeclampsia, intrauterine growth restriction, spontaneous abortion, and preterm birth, we thus propose that the immunomodulatory activity of MDSCs should be carefully considered for the therapeutic approaches targeting pregnancy complications. Copyright © 2015. Published by Elsevier Ireland Ltd.

  3. Regulatory T cells-derived IL-35 promotes the growth of adult acute myeloid leukemia blasts.

    Science.gov (United States)

    Tao, Qianshan; Pan, Ying; Wang, Yiping; Wang, Huiping; Xiong, Shudao; Li, Qing; Wang, Jia; Tao, Lili; Wang, Zhitao; Wu, Fan; Zhang, Rui; Zhai, Zhimin

    2015-11-15

    Tumor immune escape mechanism mediated by CD4+CD25+regulatory T cells (Tregs) is a key factor in the pathogenesis of acute myeloid leukemia (AML). IL-35, as a novel inhibitory cytokine, is produced by Tregs specially and regulates functions of Tregs in murine. However, IL-35 expression of Tregs in human is still disputed, and its role in AML is yet to be elucidated. In this study, we found that IL-35 was expressed highly in peripheral blood plasma of adult patients with AML and significantly correlated with the clinical stages of malignancy. Tregs-derived from adult AML patients produced IL-35 in a stimulation-dependent manner. IL-35 promoted AML blasts immune escape by expanding Tregs and inhibiting CD4+CD25-effector T cells (Teffs). Furthermore, IL-35 directly promoted the proliferation of AML blasts and reduced the apoptosis of AML blasts. Together, our study demonstrates that IL-35-derived from Tregs promotes the growth of adult AML blasts, suggesting that IL-35 has an important role in the pathogenesis of AML.

  4. Pathogenic Fungi Regulate Immunity by Inducing Neutrophilic Myeloid-Derived Suppressor Cells

    Science.gov (United States)

    Rieber, Nikolaus; Singh, Anurag; Öz, Hasan; Carevic, Melanie; Bouzani, Maria; Amich, Jorge; Ost, Michael; Ye, Zhiyong; Ballbach, Marlene; Schäfer, Iris; Mezger, Markus; Klimosch, Sascha N.; Weber, Alexander N.R.; Handgretinger, Rupert; Krappmann, Sven; Liese, Johannes; Engeholm, Maik; Schüle, Rebecca; Salih, Helmut Rainer; Marodi, Laszlo; Speckmann, Carsten; Grimbacher, Bodo; Ruland, Jürgen; Brown, Gordon D.; Beilhack, Andreas; Loeffler, Juergen; Hartl, Dominik

    2015-01-01

    Summary Despite continuous contact with fungi, immunocompetent individuals rarely develop pro-inflammatory antifungal immune responses. The underlying tolerogenic mechanisms are incompletely understood. Using both mouse models and human patients, we show that infection with the human pathogenic fungi Aspergillus fumigatus and Candida albicans induces a distinct subset of neutrophilic myeloid-derived suppressor cells (MDSCs), which functionally suppress T and NK cell responses. Mechanistically, pathogenic fungi induce neutrophilic MDSCs through the pattern recognition receptor Dectin-1 and its downstream adaptor protein CARD9. Fungal MDSC induction is further dependent on pathways downstream of Dectin-1 signaling, notably reactive oxygen species (ROS) generation as well as caspase-8 activity and interleukin-1 (IL-1) production. Additionally, exogenous IL-1β induces MDSCs to comparable levels observed during C. albicans infection. Adoptive transfer and survival experiments show that MDSCs are protective during invasive C. albicans infection, but not A. fumigatus infection. These studies define an innate immune mechanism by which pathogenic fungi regulate host defense. PMID:25771792

  5. Treating Chronic Myeloid Leukemia by Phase

    Science.gov (United States)

    ... Myeloid Leukemia (CML) Treating Chronic Myeloid Leukemia Treating Chronic Myeloid Leukemia by Phase Treatment options for people ... a stem cell donor with matching tissue type. Chronic phase The standard treatment for chronic phase CML ...

  6. Cyanobacteria from terrestrial and marine sources contain apoptogens able to overcome chemoresistance in acute myeloid leukemia cells

    OpenAIRE

    2014-01-01

    In this study, we investigated forty cyanobacterial isolates from biofilms, gastropods, brackish water and symbiotic lichen habitats. Their aqueous and organic extracts were used to screen for apoptosis-inducing activity against acute myeloid leukemia cells. A total of 28 extracts showed cytotoxicity against rat acute myeloid leukemia (IPC-81) cells. The design of the screen made it possible to eliminate known toxins, such as microcystins and nodularin, or known metabolites with anti-leukemi...

  7. Activated T cells sustain myeloid-derived suppressor cell-mediated immune suppression.

    Science.gov (United States)

    Pinton, Laura; Solito, Samantha; Damuzzo, Vera; Francescato, Samuela; Pozzuoli, Assunta; Berizzi, Antonio; Mocellin, Simone; Rossi, Carlo Riccardo; Bronte, Vincenzo; Mandruzzato, Susanna

    2016-01-12

    The expansion of myeloid derived suppressor cells (MDSCs), a suppressive population able to hamper the immune response against cancer, correlates with tumor progression and overall survival in several cancer types. We have previously shown that MDSCs can be induced in vitro from precursors present in the bone marrow and observed that these cells are able to actively proliferate in the presence of activated T cells, whose activation level is critical to drive the suppressive activity of MDSCs. Here we investigated at molecular level the mechanisms involved in the interplay between MDSCs and activated T cells. We found that activated T cells secrete IL-10 following interaction with MDSCs which, in turn, activates STAT3 phosphorylation on MDSCs then leading to B7-H1 expression. We also demonstrated that B7-H1+ MDSCs are responsible for immune suppression through a mechanism involving ARG-1 and IDO expression. Finally, we show that the expression of ligands B7-H1 and MHC class II both on in vitro-induced MDSCs and on MDSCs in the tumor microenvironment of cancer patients is paralleled by an increased expression of their respective receptors PD-1 and LAG-3 on T cells, two inhibitory molecules associated with T cell dysfunction. These findings highlight key molecules and interactions responsible for the extensive cross-talk between MDSCs and activated T cells that are at the basis of immune suppression.

  8. Single-cell transcriptomics uncovers distinct molecular signatures of stem cells in chronic myeloid leukemia.

    Science.gov (United States)

    Giustacchini, Alice; Thongjuea, Supat; Barkas, Nikolaos; Woll, Petter S; Povinelli, Benjamin J; Booth, Christopher A G; Sopp, Paul; Norfo, Ruggiero; Rodriguez-Meira, Alba; Ashley, Neil; Jamieson, Lauren; Vyas, Paresh; Anderson, Kristina; Segerstolpe, Åsa; Qian, Hong; Olsson-Strömberg, Ulla; Mustjoki, Satu; Sandberg, Rickard; Jacobsen, Sten Eirik W; Mead, Adam J

    2017-06-01

    Recent advances in single-cell transcriptomics are ideally placed to unravel intratumoral heterogeneity and selective resistance of cancer stem cell (SC) subpopulations to molecularly targeted cancer therapies. However, current single-cell RNA-sequencing approaches lack the sensitivity required to reliably detect somatic mutations. We developed a method that combines high-sensitivity mutation detection with whole-transcriptome analysis of the same single cell. We applied this technique to analyze more than 2,000 SCs from patients with chronic myeloid leukemia (CML) throughout the disease course, revealing heterogeneity of CML-SCs, including the identification of a subgroup of CML-SCs with a distinct molecular signature that selectively persisted during prolonged therapy. Analysis of nonleukemic SCs from patients with CML also provided new insights into cell-extrinsic disruption of hematopoiesis in CML associated with clinical outcome. Furthermore, we used this single-cell approach to identify a blast-crisis-specific SC population, which was also present in a subclone of CML-SCs during the chronic phase in a patient who subsequently developed blast crisis. This approach, which might be broadly applied to any malignancy, illustrates how single-cell analysis can identify subpopulations of therapy-resistant SCs that are not apparent through cell-population analysis.

  9. HIF-α/MIF and NF-κB/IL-6 axes contribute to the recruitment of CD11b+Gr-1+ myeloid cells in hypoxic microenvironment of HNSCC.

    Science.gov (United States)

    Zhu, Guiquan; Tang, Yaling; Geng, Ning; Zheng, Min; Jiang, Jian; Li, Ling; Li, Kaide; Lei, Zhengge; Chen, Wei; Fan, Yunlong; Ma, Xiangrui; Li, Longjiang; Wang, Xiaoyi; Liang, Xinhua

    2014-02-01

    CD11b+Gr-1+ myeloid cells have gained much attention due to their roles in tumor immunity suppression as well as promotion of angiogenesis, invasion, and metastases. However, the mechanisms by which CD11b+Gr-1+ myeloid cells recruit to the tumor site have not been well clarified. In the present study, we showed that hypoxia could stimulate the migration of CD11b+Gr-1+ myeloid cells through increased production of macrophage migration inhibitory factor (MIF) and interleukin-6 (IL-6) by head and neck squamous cell carcinoma (HNSCC) cells. Hypoxia-inducible factor-1α (HIF-1α)- and HIF-2α-dependent MIF regulated chemotaxis, differentiation, and pro-angiogenic function of CD11b+Gr-1+ myeloid cells through binding to CD74/CXCR2, and CD74/CXCR4 complexes, and then activating p38/mitogen-activated protein kinase (MAPK) and phosphatidylinositide 3-kinases (PI3K)/AKT signaling pathways. Knockdown (KD) of HIF-1α and HIF-2α in HNSCC cells decreased MIF level but failed to inhibit the CD11b+Gr-1+ myeloid cell migration, because HIF-1α/2α KD enhanced nuclear factor κB (NF-κB) activity that increased IL-6 secretion. Simultaneously blocking NF-κB and HIF-1α/HIF-2α had better inhibitory effect on CD11b+Gr-1+ myeloid cell recruitment in the hypoxic zone than individually silencing HIF-1α/2α or NF-κB. In conclusion, the interaction between HIF-α/MIF and NF-κB/IL-6 axes plays an important role in the hypoxia-induced accumulation of CD11b+Gr-1+ myeloid cells and tumor growth in HNSCC.

  10. Expansion of myeloid-derived suppressor cells promotes differentiation of regulatory T cells in HIV-1+ individuals.

    Science.gov (United States)

    Wang, Ling; Zhao, Juan; Ren, Jun P; Wu, Xiao Y; Morrison, Zheng D; Elgazzar, Mohamed A; Ning, Shun B; Moorman, Jonathan P; Yao, Zhi Q

    2016-06-19

    Regulatory T cells (Tregs) contribute to HIV-1 disease progression by impairing antiviral immunity; however, the precise mechanisms responsible for the development of Tregs in the setting of HIV-1 infection are incompletely understood. In this study, we provide evidence that HIV-induced expansion of monocytic myeloid-derived suppressor cells (M-MDSCs) promote the differentiation of Foxp3 Tregs. We measured MDSC induction and cytokine expression by flow cytometry and analyzed their functions by coculturing experiments. We observed a dramatic increase in M-MDSC frequencies in the peripheral blood of HIV-1 seropositive (HIV-1) individuals, even in those on antiretroviral therapy with undetectable viremia, when compared with healthy participants. We also observed increases in M-MDSCs after incubating healthy peripheral mononuclear cells (PBMCs) with HIV-1 proteins (gp120 or Tat) or Toll-like receptor 4 ligand lipopolysaccharides in vitro, an effect that could be abrogated in the presence of the phosphorylated signal transducer and activator of transcription 3 inhibitor, STA-21. Functional analyses indicated that M-MDSCs from HIV-1 individuals express higher levels of IL-10, tumor growth factor-β, IL-4 receptor α, p47, programmed death-ligand 1, and phosphorylated signal transducer and activator of transcription 3 - all of which are known mediators of myelopoiesis and immunosuppression. Importantly, incubation of healthy CD4 T cells with MDSCs derived from HIV-1 individuals significantly increased differentiation of Foxp3 Tregs. In addition, depletion of MDSCs from PBMCs of HIV-1 individuals led to a significant reduction of Foxp3 Tregs and increase of IFNγ production by CD4 T effector cells. These results suggest that HIV-induced MDSCs promote Treg cell development and inhibit T cell function - a hallmark of many chronic infectious diseases.

  11. Myeloid infection links epithelial and B cell tropisms of Murid Herpesvirus-4.

    Directory of Open Access Journals (Sweden)

    Bruno Frederico

    2012-09-01

    Full Text Available Gamma-herpesviruses persist in lymphocytes and cause disease by driving their proliferation. Lymphocyte infection is therefore a key pathogenetic event. Murid Herpesvirus-4 (MuHV-4 is a rhadinovirus that like the related Kaposi's Sarcoma-associated Herpesvirus persists in B cells in vivo yet infects them poorly in vitro. Here we used MuHV-4 to understand how virion tropism sets the path to lymphocyte colonization. Virions that were highly infectious in vivo showed a severe post-binding block to B cell infection. Host entry was accordingly an epithelial infection and B cell infection a secondary event. Macrophage infection by cell-free virions was also poor, but improved markedly when virion binding improved or when macrophages were co-cultured with infected fibroblasts. Under the same conditions B cell infection remained poor; it improved only when virions came from macrophages. This reflected better cell penetration and correlated with antigenic changes in the virion fusion complex. Macrophages were seen to contact acutely infected epithelial cells, and cre/lox-based virus tagging showed that almost all the virus recovered from lymphoid tissue had passed through lysM(+ and CD11c(+ myeloid cells. Thus MuHV-4 reached B cells in 3 distinct stages: incoming virions infected epithelial cells; infection then passed to myeloid cells; glycoprotein changes then allowed B cell infection. These data identify new complexity in rhadinovirus infection and potentially also new vulnerability to intervention.

  12. Myeloid infection links epithelial and B cell tropisms of Murid Herpesvirus-4.

    Science.gov (United States)

    Frederico, Bruno; Milho, Ricardo; May, Janet S; Gillet, Laurent; Stevenson, Philip G

    2012-09-01

    Gamma-herpesviruses persist in lymphocytes and cause disease by driving their proliferation. Lymphocyte infection is therefore a key pathogenetic event. Murid Herpesvirus-4 (MuHV-4) is a rhadinovirus that like the related Kaposi's Sarcoma-associated Herpesvirus persists in B cells in vivo yet infects them poorly in vitro. Here we used MuHV-4 to understand how virion tropism sets the path to lymphocyte colonization. Virions that were highly infectious in vivo showed a severe post-binding block to B cell infection. Host entry was accordingly an epithelial infection and B cell infection a secondary event. Macrophage infection by cell-free virions was also poor, but improved markedly when virion binding improved or when macrophages were co-cultured with infected fibroblasts. Under the same conditions B cell infection remained poor; it improved only when virions came from macrophages. This reflected better cell penetration and correlated with antigenic changes in the virion fusion complex. Macrophages were seen to contact acutely infected epithelial cells, and cre/lox-based virus tagging showed that almost all the virus recovered from lymphoid tissue had passed through lysM(+) and CD11c(+) myeloid cells. Thus MuHV-4 reached B cells in 3 distinct stages: incoming virions infected epithelial cells; infection then passed to myeloid cells; glycoprotein changes then allowed B cell infection. These data identify new complexity in rhadinovirus infection and potentially also new vulnerability to intervention.

  13. Small?molecule Hedgehog inhibitor attenuates the leukemia?initiation potential of acute myeloid leukemia cells

    OpenAIRE

    Fukushima, Nobuaki; Minami, Yosuke; Kakiuchi, Seiji; Kuwatsuka, Yachiyo; Hayakawa, Fumihiko; Jamieson, Catoriona; Kiyoi, Hitoshi; Naoe, Tomoki

    2016-01-01

    Aberrant activation of the Hedgehog signaling pathway has been implicated in the maintenance of leukemia stem cell populations in several model systems. PF?04449913 (PF?913) is a selective, small?molecule inhibitor of Smoothened, a membrane protein that regulates the Hedgehog pathway. However, details of the proof?of?concept and mechanism of action of PF?913 following administration to patients with acute myeloid leukemia (AML) are unclear. This study examined the role of the Hedgehog signali...

  14. Autologous Stem Cell Transplantation in Patients with Acute Myeloid Leukemia: a Single-Centre Experience

    Directory of Open Access Journals (Sweden)

    Kakucs Enikő

    2013-04-01

    Full Text Available Introduction: Autologous haemopoietic stem cell transplantation (SCT is an important treatment modality for patients with acute myeloid leukemia with low and intermediate risk disease. It has served advantages over allogenic transplantation, because it does not need a matched donor, there is no graft versus host disease, there are less complications and a faster immune reconstitution than in the allo-setting. The disadvantage is the lack of the graft versus leukaemia effect.

  15. Loss of C/EBP alpha cell cycle control increases myeloid progenitor proliferation and transforms the neutrophil granulocyte lineage

    DEFF Research Database (Denmark)

    Porse, Bo T; Bryder, David; Theilgaard-Mönch, Kim;

    2005-01-01

    CCAAT/enhancer binding protein (C/EBP)alpha is a myeloid-specific transcription factor that couples lineage commitment to terminal differentiation and cell cycle arrest, and is found mutated in 9% of patients who have acute myeloid leukemia (AML). We previously showed that mutations which......, accumulation of myeloblasts and promyelocytes, and expansion of myeloid progenitor populations--all characteristics of AML. Circulating myeloblasts and hepatic leukocyte infiltration were observed, but thrombocytopenia, anemia, and elevated leukocyte count--normally associated with AML-were absent...

  16. Haemostatic function and biomarkers of endothelial damage before and after platelet transfusion in patients with acute myeloid leukaemia

    DEFF Research Database (Denmark)

    Larsen, A M; Leinøe, E B; Johansson, P I

    2015-01-01

    and after platelet transfusion in patients with acute myeloid leukaemia. MATERIALS AND METHODS: Blood was sampled before, 1 and 24 h after platelet transfusion. Primary and secondary haemostasis was evaluated by whole blood aggregometry (Multiplate) and thromboelastography (TEG). Endothelial biomarkers (s......OBJECTIVES: The beneficial effect of platelet transfusion on haemostasis is well established, but there is emerging evidence that platelet transfusion induces an inflammatory response in vascular endothelial cells. BACKGROUND: We investigated haemostatic function and endothelial biomarkers before......ICAM-1, syndecan-1, sThrombomodulin, sVE-Cadherin) and platelet activation biomarkers (sCD40L, TGF-beta) were investigated along with haematology/biochemistry analyses. RESULTS: Twenty-two patients were included. Despite continued low platelet counts, platelet transfusion normalised the median values...

  17. A20 (Tnfaip3 deficiency in myeloid cells protects against influenza A virus infection.

    Directory of Open Access Journals (Sweden)

    Jonathan Maelfait

    Full Text Available The innate immune response provides the first line of defense against viruses and other pathogens by responding to specific microbial molecules. Influenza A virus (IAV produces double-stranded RNA as an intermediate during the replication life cycle, which activates the intracellular pathogen recognition receptor RIG-I and induces the production of proinflammatory cytokines and antiviral interferon. Understanding the mechanisms that regulate innate immune responses to IAV and other viruses is of key importance to develop novel therapeutic strategies. Here we used myeloid cell specific A20 knockout mice to examine the role of the ubiquitin-editing protein A20 in the response of myeloid cells to IAV infection. A20 deficient macrophages were hyperresponsive to double stranded RNA and IAV infection, as illustrated by enhanced NF-κB and IRF3 activation, concomitant with increased production of proinflammatory cytokines, chemokines and type I interferon. In vivo this was associated with an increased number of alveolar macrophages and neutrophils in the lungs of IAV infected mice. Surprisingly, myeloid cell specific A20 knockout mice are protected against lethal IAV infection. These results challenge the general belief that an excessive host proinflammatory response is associated with IAV-induced lethality, and suggest that under certain conditions inhibition of A20 might be of interest in the management of IAV infections.

  18. Natural Product Vibsanin A Induces Differentiation of Myeloid Leukemia Cells through PKC Activation.

    Science.gov (United States)

    Yu, Zu-Yin; Xiao, He; Wang, Li-Mei; Shen, Xing; Jing, Yu; Wang, Lin; Sun, Wen-Feng; Zhang, Yan-Feng; Cui, Yu; Shan, Ya-Jun; Zhou, Wen-Bing; Xing, Shuang; Xiong, Guo-Lin; Liu, Xiao-Lan; Dong, Bo; Feng, Jian-Nan; Wang, Li-Sheng; Luo, Qing-Liang; Zhao, Qin-Shi; Cong, Yu-Wen

    2016-05-01

    All-trans retinoic acid (ATRA)-based cell differentiation therapy has been successful in treating acute promyelocytic leukemia, a unique subtype of acute myeloid leukemia (AML). However, other subtypes of AML display resistance to ATRA-based treatment. In this study, we screened natural, plant-derived vibsane-type diterpenoids for their ability to induce differentiation of myeloid leukemia cells, discovering that vibsanin A potently induced differentiation of AML cell lines and primary blasts. The differentiation-inducing activity of vibsanin A was mediated through direct interaction with and activation of protein kinase C (PKC). Consistent with these findings, pharmacological blockade of PKC activity suppressed vibsanin A-induced differentiation. Mechanistically, vibsanin A-mediated activation of PKC led to induction of the ERK pathway and decreased c-Myc expression. In mouse xenograft models of AML, vibsanin A administration prolonged host survival and inhibited PKC-mediated inflammatory responses correlated with promotion of skin tumors in mice. Collectively, our results offer a preclinical proof of concept for vibsanin A as a myeloid differentiation-inducing compound, with potential application as an antileukemic agent. Cancer Res; 76(9); 2698-709. ©2016 AACR.

  19. Inhibition of protein kinase CK2 with the clinical-grade small ATP-competitive compound CX-4945 or by RNA interference unveils its role in acute myeloid leukemia cell survival, p53-dependent apoptosis and daunorubicin-induced cytotoxicity.

    Science.gov (United States)

    Quotti Tubi, Laura; Gurrieri, Carmela; Brancalion, Alessandra; Bonaldi, Laura; Bertorelle, Roberta; Manni, Sabrina; Pavan, Laura; Lessi, Federica; Zambello, Renato; Trentin, Livio; Adami, Fausto; Ruzzene, Maria; Pinna, Lorenzo A; Semenzato, Gianpietro; Piazza, Francesco

    2013-10-12

    The involvement of protein kinase CK2 in sustaining cancer cell survival could have implications also in the resistance to conventional and unconventional therapies. Moreover, CK2 role in blood tumors is rapidly emerging and this kinase has been recognized as a potential therapeutic target. Phase I clinical trials with the oral small ATP-competitive CK2 inhibitor CX-4945 are currently ongoing in solid tumors and multiple myeloma. We have analyzed the expression of CK2 in acute myeloid leukemia and its function in cell growth and in the response to the chemotherapeutic agent daunorubicin We employed acute myeloid leukemia cell lines and primary blasts from patients grouped according to the European LeukemiaNet risk classification. Cell survival, apoptosis and sensitivity to daunorubicin were assessed by different means. p53-dependent CK2-inhibition-induced apoptosis was investigated in p53 wild-type and mutant cells. CK2a was found highly expressed in the majority of samples across the different acute myeloid leukemia prognostic subgroups as compared to normal CD34+ hematopoietic and bone marrow cells. Inhibition of CK2 with CX-4945, K27 or siRNAs caused a p53-dependent acute myeloid leukemia cell apoptosis. CK2 inhibition was associated with a synergistic increase of the cytotoxic effects of daunorubicin. Baseline and daunorubicin-induced STAT3 activation was hampered upon CK2 blockade. These results suggest that CK2 is over expressed across the different acute myeloid leukemia subsets and acts as an important regulator of acute myeloid leukemia cell survival. CK2 negative regulation of the protein levels of tumor suppressor p53 and activation of the STAT3 anti-apoptotic pathway might antagonize apoptosis and could be involved in acute myeloid leukemia cell resistance to daunorubicin.

  20. Matrine induces apoptosis in human acute myeloid leukemia cells via the mitochondrial pathway and Akt inactivation.

    Directory of Open Access Journals (Sweden)

    Shenghui Zhang

    Full Text Available Acute myeloid leukemia (AML is a hematological malignancy characterized by a rapid increase in the number of immature myeloid cells in bone marrow. Despite recent advances in the treatment, AML remains an incurable disease. Matrine, a major component extracted from Sophora flavescens Ait, has been demonstrated to exert anticancer effects on various cancer cell lines. However, the effects of matrine on AML remain largely unknown. Here we investigated its anticancer effects and underlying mechanisms on human AML cells in vitro and in vivo. The results showed that matrine inhibited cell viability and induced cell apoptosis in AML cell lines as well as primary AML cells from patients with AML in a dose- and time-dependent manner. Matrine induced apoptosis by collapsing the mitochondrial membrane potential, inducing cytochrome c release from mitochondria, reducing the ratio of Bcl-2/Bax, increasing activation of caspase-3, and decreasing the levels of p-Akt and p-ERK1/2. The apoptotic effects of matrine on AML cells were partially blocked by a caspase-3 inhibitor Z-DEVD-FMK and a PI3K/Akt activator IGF-1, respectively. Matrine potently inhibited in vivo tumor growth following subcutaneous inoculation of HL-60 cells in SCID mice. These findings indicate that matrine can inhibit cell proliferation and induce apoptosis of AML cells and may be a novel effective candidate as chemotherapeutic agent against AML.

  1. miR-34a expands myeloid-derived suppressor cells via apoptosis inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Anfei, E-mail: huang_anfei@163.com [Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu Province (China); Zhang, Haitao, E-mail: zhanghtjp@126.com [Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou 215021, Jiangsu Province (China); Chen, Si, E-mail: chensisdyxb@126.com [Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu Province (China); Xia, Fei, E-mail: xiafei87@gmail.com [Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu Province (China); Yang, Yi, E-mail: 602744364@qq.com [Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu Province (China); Dong, Fulu, E-mail: adiok0903@126.com [Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu Province (China); Sun, Di, E-mail: dongfl@suda.edu.cn [Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu Province (China); Xiong, Sidong, E-mail: sdxiong@suda.edu.cn [Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu Province (China); Zhang, Jinping, E-mail: j_pzhang@suda.edu.cn [Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu Province (China)

    2014-08-15

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population and show significant expansion under pathological conditions. microRNA plays important roles in many biological processes, whether microRNAs have a function in the expansion of MDSCs is still not very clear. In this study, miR-34a overexpression can induce the expansion of MDSCs in bone marrow chimera and transgenic mice model. The experimental results suggest that miR-34a inhibited the apoptosis of MDSCs but did not affect the proliferation of MDSCs. The distinct mRNA microarray profiles of MDSCs of wild type and miR-34a over-expressing MDSCs combined with the target prediction of miR-34a suggest that miR-34a may target genes such as p2rx7, Tia1, and plekhf1 to inhibit the apoptosis of MDSCs. Taken together, miR-34a contributes to the expansion of MDSCs by inhibiting the apoptosis of MDSCs. - Highlights: • Over-expression of miR-34a increases the number of MDSCs. • miR-34a inhibits the apoptosis of MDSCs, but does not affects their proliferation. • miR-34a may inhibit the apoptosis of MDSCs via targeting the p2rx7, Tia1 and plekhf1.

  2. Doxorubicin Eliminates Myeloid-Derived Suppressor Cells and Enhances the Efficacy of Adoptive T Cell Transfer in Breast Cancer

    Science.gov (United States)

    Alizadeh, Darya; Trad, Malika; Hanke, Neale T.; Larmonier, Claire B.; Janikashvili, Nona; Bonnotte, Bernard; Katsanis, Emmanuel; Larmonier, Nicolas

    2013-01-01

    Myeloid-derived suppressor cells (MDSC) expand in tumor-bearing hosts and play a central role in cancer immune evasion by inhibiting adaptive and innate immunity. They therefore represent a major obstacle for successful cancer immunotherapy. Different strategies have thus been explored to deplete and/or inactivate MDSC in vivo. Using a murine mammary cancer model, we demonstrated that doxorubicin selectively eliminates MDSC in the spleen, blood and tumor beds. Furthermore, residual MDSC from doxorubicin-treated mice exhibited impaired suppressive function. Importantly, the frequency of CD4+ and CD8+ T lymphocytes and consequently the effector lymphocytes or natural killer (NK) to suppressive MDSC ratios were significantly increased following doxorubicin treatment of tumor-bearing mice. In addition, the proportion of natural killer (NK) and cytotoxic T cell (CTL) expressing perforin and granzyme B and of CTL producing IFNγ was augmented by doxorubicin administration. Of therapeutic relevance, this drug efficiently combined with Th1 or Th17 lymphocytes to suppress tumor development and metastatic disease. MDSC isolated from patients with different types of cancer were also sensitive to doxorubicin-mediated cytotoxicity in vitro. These results thus indicate that doxorubicin may be used not only as a direct cytotoxic drug against tumor cells, but also as a potent immunomodulatory agent that selectively impairs MDSC-induced immunosuppression, thereby fostering the efficacy of T cell-based immunotherapy. PMID:24197130

  3. Myeloid derived suppressor cells are present at high frequency in neonates and suppress in vitro T cell responses.

    Directory of Open Access Journals (Sweden)

    Ana Gervassi

    Full Text Available Over 4 million infants die each year from infections, many of which are vaccine-preventable. Young infants respond relatively poorly to many infections and vaccines, but the basis of reduced immunity in infants is ill defined. We sought to investigate whether myeloid-derived suppressor cells (MDSC represent one potential impediment to protective immunity in early life, which may help inform strategies for effective vaccination prior to pathogen exposure. We enrolled healthy neonates and children in the first 2 years of life along with healthy adult controls to examine the frequency and function of MDSC, a cell population able to potently suppress T cell responses. We found that MDSC, which are rarely seen in healthy adults, are present in high numbers in neonates and their frequency rapidly decreases during the first months of life. We determined that these neonatal MDSC are of granulocytic origin (G-MDSC, and suppress both CD4+ and CD8+ T cell proliferative responses in a contact-dependent manner and gamma interferon production. Understanding the role G-MDSC play in infant immunity could improve vaccine responsiveness in newborns and reduce mortality due to early-life infections.

  4. Myeloid derived suppressor cells are present at high frequency in neonates and suppress in vitro T cell responses.

    Science.gov (United States)

    Gervassi, Ana; Lejarcegui, Nicholas; Dross, Sandra; Jacobson, Amanda; Itaya, Grace; Kidzeru, Elvis; Gantt, Soren; Jaspan, Heather; Horton, Helen

    2014-01-01

    Over 4 million infants die each year from infections, many of which are vaccine-preventable. Young infants respond relatively poorly to many infections and vaccines, but the basis of reduced immunity in infants is ill defined. We sought to investigate whether myeloid-derived suppressor cells (MDSC) represent one potential impediment to protective immunity in early life, which may help inform strategies for effective vaccination prior to pathogen exposure. We enrolled healthy neonates and children in the first 2 years of life along with healthy adult controls to examine the frequency and function of MDSC, a cell population able to potently suppress T cell responses. We found that MDSC, which are rarely seen in healthy adults, are present in high numbers in neonates and their frequency rapidly decreases during the first months of life. We determined that these neonatal MDSC are of granulocytic origin (G-MDSC), and suppress both CD4+ and CD8+ T cell proliferative responses in a contact-dependent manner and gamma interferon production. Understanding the role G-MDSC play in infant immunity could improve vaccine responsiveness in newborns and reduce mortality due to early-life infections.

  5. Clinical activity of azacitidine in patients who relapse after allogeneic stem cell transplantation for acute myeloid leukemia

    DEFF Research Database (Denmark)

    Craddock, Charles; Labopin, Myriam; Robin, Marie

    2016-01-01

    Disease relapse is the most common cause of treatment failure after allogeneic stem cell transplantation for acute myeloid leukemia and myelodysplastic syndromes, yet treatment options for such patients remain extremely limited. Azacitidine is an important new therapy in high-risk myelodysplastic...... syndromes and acute myeloid leukemia but its role in patients who relapse post allograft has not been defined. We studied the tolerability and activity of azacitidine in 181 patients who relapsed after an allograft for acute myeloid leukemia (n=116) or myelodysplastic syndromes (n=65). Sixty-nine patients...... conclude that azacitidine represents an important new therapy in selected patients with acute myeloid leukemia/myelodysplastic syndromes who relapse after allogeneic stem cell transplantation. Prospective studies to confirm optimal treatment options in this challenging patient population are required....

  6. Identifying alemtuzumab as an anti-myeloid cell antiangiogenic therapy for the treatment of ovarian cancer

    Directory of Open Access Journals (Sweden)

    Coukos George

    2009-06-01

    Full Text Available Abstract Background Murine studies suggest that myeloid cells such as vascular leukocytes (VLC and Tie2+ monocytes play a critical role in tumor angiogenesis and vasculogenesis. Myeloid cells are a primary cause of resistance to anti-VEGF therapy. The elimination of these cells from the tumor microenvironment significantly restricts tumor growth in both spontaneous and xenograft murine tumor models. Thus animal studies indicate that myeloid cells are potential therapeutic targets for solid tumor therapy. Abundant VLC and Tie2+ monocytes have been reported in human cancer. Unfortunately, the importance of VLC in human cancer growth remains untested as there are no confirmed therapeutics to target human VLC. Methods We used FACS to analyze VLC in ovarian and non-ovarian tumors, and characterize the relationship of VLC and Tie2-monocytes. We performed qRT-PCR and FACS on human VLC to assess the expression of the CD52 antigen, the target of the immunotherapeutic Alemtuzumab. We assessed Alemtuzumab's ability to induce complement-mediated VLC killing in vitro and in human tumor ascites. Finally we assessed the impact of anti-CD52 immuno-toxin therapy on murine ovarian tumor growth. Results Human VLC are present in ovarian and non-ovarian tumors. The majority of VLC appear to be Tie2+ monocytes. VLC and Tie2+ monocytes express high levels of CD52, the target of the immunotherapeutic Alemtuzumab. Alemtuzumab potently induces complement-mediated lysis of VLC in vitro and ex-vivo in ovarian tumor ascites. Anti-CD52 immunotherapy targeting VLC restricts tumor angiogenesis and growth in murine ovarian cancer. Conclusion These studies confirm VLC/myeloid cells as therapeutic targets in ovarian cancer. Our data provide critical pre-clinical evidence supporting the use of Alemtuzumab in clinical trials to test its efficacy as an anti-myeloid cell antiangiogenic therapeutic in ovarian cancer. The identification of an FDA approved anti-VLC agent with a history

  7. Risk factors for therapy-related myelodysplastic syndrome and acute myeloid leukemia treated with allogeneic stem cell transplantation.

    OpenAIRE

    2009-01-01

    International audience; BACKGROUND: After successful treatment of malignant diseases, therapy-related myelodysplastic syndrome and acute myeloid leukemia have emerged as significant problems. DESIGN AND METHODS: The aim of this study was to investigate outcome and risk factors in patients with therapy-related myelodysplastic syndrome or acute myeloid leukemia who underwent allogeneic stem cell transplantation. Between 1981 and 2006, 461 patients with therapy-related myelodysplastic syndrome o...

  8. Gr-1+CD11b+ myeloid cells efficiently home to site of injury after intravenous administration and enhance diabetic wound healing by neoangiogenesis.

    Science.gov (United States)

    Tong, Xiaozhe; Lv, Gang; Huang, Jianhua; Min, Yongfen; Yang, Li; Lin, Pengnian Charles

    2014-06-01

    Vascularization is an important factor that affects diabetic wound healing. There is increasing evidence that myeloid cell lineages play a role in neovascularization. In this study, the efficiency of Gr-1+CD11b+ myeloid cells to home to the site of injury and enhance diabetic wound healing by neoangiogenesis after intravenous administration was investigated. Gr-1+CD11b+ myeloid cells were injected into tail vein after establishment of dorsal window chamber, hindlimb ischaemia and ear-punch injury in diabetic or non-diabetic mice. The Gr-1+CD11b+ myeloid cells efficiently homed to the site of injury after intravenous administration and increased neoangiogenesis. The chemokine receptor type 4 (CXCR4) is robustly expressed by Gr-1+CD11b+ myeloid cells. Inhibition of CXCR4 decreases the homing ability of Gr-1+CD11b+ myeloid cells to the site of injury, which indicates that the CXCR4/SDF-1 axis plays an important role in the homing of Gr-1+CD11b+ myeloid cells to the site of injury. In addition, Gr-1+CD11b+ myeloid cells were found to improve blood flow recovery of ischaemic limb and enhance wound healing in diabetic mice by neoangiogenesis after intravenous administration. Taken together, the results of this study suggest that Gr-1+CD11b+ myeloid cells may serve as a potential cell therapy for diabetic wound healing.

  9. MBA-induced differentiation of myeloid leukemic cell lines is associated with altered G1 cell cycle regulators and related genes

    Institute of Scientific and Technical Information of China (English)

    王钦红; 谢毅; 范华骅

    2004-01-01

    @@The proliferation and differentiation of hematopoietic cells can be regulated by a number of physiological agents including hexamethylene bisacetamide (HMBA). Clinically, HMBA has been used for the treatment of acute myeloid leukemia and myelodysplastic syndrome.1 However, the mechanism of the effect of HMBA on the differentiation of myeloid leukemic cells is largely unkown. Up to now, related reports have not been found. We used HL-60 and U937 cell lines to study the effect of HMBA on the differentiation of myeloid leukemic cells and to explore the possible mechanism.

  10. Interleukin-10 production by myeloid-derived suppressor cells contributes to bacterial persistence during Staphylococcus aureus orthopedic biofilm infection

    Science.gov (United States)

    Heim, Cortney E.; Vidlak, Debbie; Kielian, Tammy

    2015-01-01

    Staphylococcus aureus is known to establish biofilms on medical devices. We recently demonstrated that Ly6GhighLy6C+ myeloid-derived suppressor cells are critical for allowing S. aureus biofilms to subvert immune-mediated clearance; however, the mechanisms whereby myeloid-derived suppressor cells promote biofilm persistence remain unknown. Interleukin-10 expression was significantly increased in a mouse model of S. aureus orthopedic implant biofilm infection with kinetics that mirrored myeloid-derived suppressor cell recruitment. Because myeloid-derived suppressor cells produce interleukin-10, we explored whether it was involved in orchestrating the nonproductive immune response that facilitates biofilm formation. Analysis of interleukin-10–green fluorescent protein reporter mice revealed that Ly6GhighLy6C+ myeloid-derived suppressor cells were the main source of interleukin-10 during the first 2 wk of biofilm infection, whereas monocytes had negligible interleukin-10 expression until day 14. Myeloid-derived suppressor cell influx into implant-associated tissues was significantly reduced in interleukin-10 knockout mice at day 14 postinfection, concomitant with increased monocyte and macrophage infiltrates that displayed enhanced proinflammatory gene expression. Reduced myeloid-derived suppressor cell recruitment facilitated bacterial clearance, as revealed by significant decreases in S. aureus burdens in the knee joint, surrounding soft tissue, and femur of interleukin-10 knockout mice. Adoptive transfer of interleukin-10 wild-type myeloid-derived suppressor cells into S. aureus–infected interleukin-10 knockout mice restored the local biofilm-permissive environment, as evidenced by increased bacterial burdens and inhibition of monocyte proinflammatory activity. These effects were both interleukin-10-dependent and interleukin-10-independent because myeloid-derived suppressor cell–derived interleukin-10 was required for promoting biofilm growth and anti

  11. Monocyte-macrophage differentiation of acute myeloid leukemia cell lines by small molecules identified through interrogation of the Connectivity Map database.

    Science.gov (United States)

    Manzotti, Gloria; Parenti, Sandra; Ferrari-Amorotti, Giovanna; Soliera, Angela Rachele; Cattelani, Sara; Montanari, Monica; Cavalli, Daniel; Ertel, Adam; Grande, Alexis; Calabretta, Bruno

    2015-01-01

    The transcription factor C/EBPα is required for granulocytic differentiation of normal myeloid progenitors and is frequently inactivated in acute myeloid leukemia (AML) cells. Ectopic expression of C/EBPα in AML cells suppresses proliferation and induces differentiation suggesting that restoring C/EBPα expression/activity in AML cells could be therapeutically useful. Unfortunately, current approaches of gene or protein delivery in leukemic cells are unsatisfactory. However, "drug repurposing" is becoming a very attractive strategy to identify potential new uses for existing drugs. In this study, we assessed the biological effects of candidate C/EBPα-mimetics identified by interrogation of the Connectivity Map database. We found that amantadine, an antiviral and anti-Parkinson agent, induced a monocyte-macrophage-like differentiation of HL60, U937, Kasumi-1 myeloid leukemia cell lines, as indicated by morphology and differentiation antigen expression, when used in combination with suboptimal concentration of all trans retinoic acid (ATRA) or Vit D3. The effect of amantadine depends, in part, on increased activity of the vitamin D receptor (VDR), since it induced VDR expression and amantadine-dependent monocyte-macrophage differentiation of HL60 cells was blocked by expression of dominant-negative VDR. These results reveal a new function for amantadine and support the concept that screening of the Connectivity Map database can identify small molecules that mimic the effect of transcription factors required for myelo-monocytic differentiation.

  12. Establishing the flow cytometric assessment of myeloid cells in kidney ischemia/reperfusion injury.

    Science.gov (United States)

    Williams, Timothy M; Wise, Andrea F; Alikhan, Maliha A; Layton, Daniel S; Ricardo, Sharon D

    2014-03-01

    Polychromatic flow cytometry is a powerful tool for assessing populations of cells in the kidney through times of homeostasis, disease and tissue remodeling. In particular, macrophages have been identified as having central roles in these three settings. However, because of the plasticity of myeloid cells it has been difficult to define a specific immunophenotype for these cells in the kidney. This study developed a gating strategy for identifying and assessing monocyte and macrophage subpopulations, along with neutrophils and epithelial cells in the healthy kidney and following ischemia/reperfusion (IR) injury in mice, using antibodies against CD45, CD11b, CD11c, Ly6C, Ly6G, F4/80, CSF-1R (CD115), MHC class II, mannose receptor (MR or CD206), an alternatively activated macrophage marker, and the epithelial cell adhesion marker (EpCAM or CD326). Backgating analysis and assessment of autofluorescence was used to extend the knowledge of various cell types and the changes that occur in the kidney at various time-points post-IR injury. In addition, the impact of enzymatic digestion of kidneys on cell surface markers and cell viability was assessed. Comparisons of kidney myeloid populations were also made with those in the spleen. These results provide a useful reference for future analyses of therapies aimed at modulating inflammation and enhancing endogenous remodeling following kidney injury.

  13. Activated myeloid dendritic cells accumulate and co-localize with CD3+ T cells in coronary artery lesions in patients with Kawasaki disease.

    Science.gov (United States)

    Yilmaz, Atilla; Rowley, Anne; Schulte, Danica J; Doherty, Terence M; Schröder, Nicolas W J; Fishbein, Michael C; Kalelkar, Mitra; Cicha, Iwona; Schubert, Katja; Daniel, Werner G; Garlichs, Christoph D; Arditi, Moshe

    2007-08-01

    Emerging evidence implicating the participation of dendritic cells (DCs) and T cells in various vascular inflammatory diseases such as giant cell arteritis, Takayasu's arteritis, and atherosclerosis led us to hypothesize that they might also participate in the pathogenesis of coronary arteritis in Kawasaki disease (KD). Coronary artery specimens from 4 patients with KD and 6 control patients were obtained. Immunohistochemical and computer-assisted histomorphometric analyses were performed to detect all myeloid DCs (S-100(+), fascin(+)), all plasmacytoid DCs (CD123(+)) as well as specific DC subsets (mature myeloid DCs [CD83(+)], myeloid [BDCA-1(+)] and plasmacytoid DC precursors [BDCA-2(+)]), T cells (CD3(+)), and all antigen-presenting cells (HLA-DR(+)). Co-localization of DCs with T cells was assessed using double immunostaining. Significantly more myeloid DCs at a precursor, immature or mature stage were found in coronary lesions of KD patients than in controls. Myeloid DC precursors were distributed equally in the intima and adventitia. Mature myeloid DCs were particularly abundant in the adventitia. There was a significant correlation between mature DCs and HLA-DR expression. Double immunostaining demonstrated frequent contacts between myeloid DCs and T cells in the outer media and adventitia. Plasmacytoid DC precursors were rarely found in the adventitia. In conclusion, coronary artery lesions of KD patients contain increased numbers of mature myeloid DCs with high HLA-DR expression and frequent T cell contacts detected immunohistochemically. This suggests that mature arterial myeloid DCs might be activating T cells in situ and may be a significant factor in the pathogenesis of coronary arteritis in KD.

  14. Donor lung derived myeloid and plasmacytoid dendritic cells differentially regulate T cell proliferation and cytokine production

    Directory of Open Access Journals (Sweden)

    Benson Heather L

    2012-03-01

    Full Text Available Abstract Background Direct allorecognition, i.e., donor lung-derived dendritic cells (DCs stimulating recipient-derived T lymphocytes, is believed to be the key mechanism of lung allograft rejection. Myeloid (cDCs and plasmacytoid (pDCs are believed to have differential effects on T cell activation. However, the roles of each DC type on T cell activation and rejection pathology post lung transplantation are unknown. Methods Using transgenic mice and antibody depletion techniques, either or both cell types were depleted in lungs of donor BALB/c mice (H-2d prior to transplanting into C57BL/6 mice (H-2b, followed by an assessment of rejection pathology, and pDC or cDC-induced proliferation and cytokine production in C57BL/6-derived mediastinal lymph node T cells (CD3+. Results Depleting either DC type had modest effect on rejection pathology and T cell proliferation. In contrast, T cells from mice that received grafts depleted of both DCs did not proliferate and this was associated with significantly reduced acute rejection scores compared to all other groups. cDCs were potent inducers of IFNγ, whereas both cDCs and pDCs induced IL-10. Both cell types had variable effects on IL-17A production. Conclusion Collectively, the data show that direct allorecognition by donor lung pDCs and cDCs have differential effects on T cell proliferation and cytokine production. Depletion of both donor lung cDC and pDC could prevent the severity of acute rejection episodes.

  15. Mast Cell: A Multi-Functional Master Cell.

    Science.gov (United States)

    Krystel-Whittemore, Melissa; Dileepan, Kottarappat N; Wood, John G

    2015-01-01

    Mast cells are immune cells of the myeloid lineage and are present in connective tissues throughout the body. The activation and degranulation of mast cells significantly modulates many aspects of physiological and pathological conditions in various settings. With respect to normal physiological functions, mast cells are known to regulate vasodilation, vascular homeostasis, innate and adaptive immune responses, angiogenesis, and venom detoxification. On the other hand, mast cells have also been implicated in the pathophysiology of many diseases, including allergy, asthma, anaphylaxis, gastrointestinal disorders, many types of malignancies, and cardiovascular diseases. This review summarizes the current understanding of the role of mast cells in many pathophysiological conditions.

  16. Identification of myeloid derived suppressor cells in the peripheral blood of tumor bearing dogs

    Directory of Open Access Journals (Sweden)

    Sherger Matthew

    2012-10-01

    Full Text Available Abstract Background Myeloid derived suppressor cells (MDSCs are a recently described population of immune cells that significantly contribute to the immunosuppression seen in cancer patients. MDSCs are one of the most important factors that limit the efficacy of cancer immunotherapy (e.g. cancer vaccines and MDSC levels are increased in cancer in multiple species. Identifying and targeting MDSCs is actively being investigated in the field of human oncology and is increasingly being investigated in veterinary oncology. The treatment of canine cancer not only benefits dogs, but is being used for translational studies evaluating and modifcying candidate therapies for use in humans. Thus, it is necessary to understand the immune alterations seen in canine cancer patients which, to date, have been relatively limited. This study investigates the use of commercially available canine antibodies to detect an immunosuppressive (CD11blow/CADO48low cell population that is increased in the peripheral blood of tumor-bearing dogs. Results Commercially available canine antibodies CD11b and CADO48A were used to evaluate white blood cells from the peripheral blood cells of forty healthy control dogs and forty untreated, tumor-bearing dogs. Tumor-bearing dogs had a statistically significant increase in CD11blow/CADO48Alow cells (7.9% as compared to the control dogs (3.6%. Additionally, sorted CD11blow/CADO48Alow generated in vitro suppressed the proliferation of canine lymphocytes. Conclusions The purpose of this study was aimed at identifying potential canine specific markers for identifying MDSCs in the peripheral blood circulation of dogs. This study demonstrates an increase in a unique CD11blow/CADO48Alow cell population in tumor-bearing dogs. This immunophenotype is consistent with described phenotypes of MDSCs in other species (i.e. mice and utilizes commercially available canine-specific antibodies. Importantly, CD11blow/CADO48Alow from a tumor environment

  17. An evidence for adhesion-mediated acquisition of acute myeloid leukemic stem cell-like immaturities

    Energy Technology Data Exchange (ETDEWEB)

    Funayama, Keiji; Shimane, Miyuki; Nomura, Hitoshi [Department of Integrative Bioscience and Biomedical Engineering, Waseda University, 4-3-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555 (Japan); Asano, Shigetaka, E-mail: asgtkmd@waseda.jp [Department of Integrative Bioscience and Biomedical Engineering, Waseda University, 4-3-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555 (Japan)

    2010-02-12

    For long-term survival in vitro and in vivo of acute myeloid leukemia cells, their adhesion to bone marrow stromal cells is indispensable. However, it is still unknown if these events are uniquely induced by the leukemic stem cells. Here we show that TF-1 human leukemia cells, once they have formed a cobblestone area by adhering to mouse bone marrow-derived MS-5 cells, can acquire some leukemic stem cell like properties in association with a change in the CD44 isoform-expression pattern and with an increase in a set of related microRNAs. These findings strongly suggest that at least some leukemia cells can acquire leukemic stem cell like properties in an adhesion-mediated stochastic fashion.

  18. Long term maintenance of myeloid leukemic stem cells cultured with unrelated human mesenchymal stromal cells

    Directory of Open Access Journals (Sweden)

    Sawa Ito

    2015-01-01

    Full Text Available Mesenchymal stromal cells (MSCs support the growth and differentiation of normal hematopoietic stem cells (HSCs. Here we studied the ability of MSCs to support the growth and survival of leukemic stem cells (LSCs in vitro. Primary leukemic blasts isolated from the peripheral blood of 8 patients with acute myeloid leukemia (AML were co-cultured with equal numbers of irradiated MSCs derived from unrelated donor bone marrow, with or without cytokines for up to 6 weeks. Four samples showed CD34+CD38− predominance, and four were predominantly CD34+CD38+. CD34+ CD38− predominant leukemia cells maintained the CD34+ CD38− phenotype and were viable for 6 weeks when co-cultured with MSCs compared to co-cultures with cytokines or medium only, which showed rapid differentiation and loss of the LSC phenotype. In contrast, CD34+ CD38+ predominant leukemic cells maintained the CD34+CD38+ phenotype when co-cultured with MSCs alone, but no culture conditions supported survival beyond 4 weeks. Cell cycle analysis showed that MSCs maintained a higher proportion of CD34+ blasts in G0 than leukemic cells cultured with cytokines. AML blasts maintained in culture with MSCs for up to 6 weeks engrafted NSG mice with the same efficiency as their non-cultured counterparts, and the original karyotype persisted after co-culture. Chemosensitivity and transwell assays suggest that MSCs provide pro-survival benefits to leukemic blasts through cell–cell contact. We conclude that MSCs support long-term maintenance of LSCs in vitro. This simple and inexpensive approach will facilitate basic investigation of LSCs and enable screening of novel therapeutic agents targeting LSCs.

  19. Circulating myeloid-derived suppressor cells in patients with pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Xiao-Dong Xu; Jun Hu; Min Wang; Feng Peng; Rui Tian; Xing-Jun Guo; Yu Xie; Ren-Yi Qin

    2016-01-01

    BACKGROUND: Myeloid-derived suppressor cells (MDSCs) are heterogeneous cell types that suppress T-cell responses in cancer patients and animal models, some MDSC subpopula-tions are increased in patients with pancreatic cancer. The present study was to investigate a specific subset of MDSCs in patients with pancreatic cancer and the mechanism of MDSCs increase in these patients. METHODS: Myeloid cells from whole blood were collected from 37 patients with pancreatic cancer, 17 with cholangiocarcinoma, and 47 healthy controls. Four pancreatic cancer cell lines were co-culturedwithnormalperipheralbloodmononuclearcells(PBMCs) to test the effect of tumor cells on the conversion of PBMCs to MDSCs. Levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) and arginase activity in the plasma of cancer patients were analyzed by enzyme-linked immunosorbent assay. RESULTS: CD14+/CD11b+/HLA-DR- MDSCs were increased in patients with pancreatic or bile duct cancer compared with those in healthy controls, and this increase was correlated with clinical cancer stage. Pancreatic cancer cell lines induced PBMCs to MDSCs in a dose-dependent manner. GM-CSF and arginase activity levels were significantly increased in the se-rum of patients with pancreatic cancer. CONCLUSIONS: MDSCsweretumorrelated:tumorcellsinduced PBMCs to MDSCs in a dose-dependent manner and circulating CD14+/CD11b+/HLA-DR- MDSCs in pancreatic cancer patients were positively correlated with tumor burden. MDSCs might be useful markers for pancreatic cancer detection and progression.

  20. Characteristics of myeloid differentiation and maturation pathway derived from human hematopoietic stem cells exposed to different linear energy transfer radiation types.

    Directory of Open Access Journals (Sweden)

    Satoru Monzen

    Full Text Available Exposure of hematopoietic stem/progenitor cells (HSPCs to ionizing radiation causes a marked suppression of mature functional blood cell production in a linear energy transfer (LET- and/or dose-dependent manner. However, little information about LET effects on the proliferation and differentiation of HSPCs has been reported. With the aim of characterizing the effects of different types of LET radiations on human myeloid hematopoiesis, in vitro hematopoiesis in Human CD34(+ cells exposed to carbon-ion beams or X-rays was compared. Highly purified CD34(+ cells exposed to each form of radiation were plated onto semi-solid culture for a myeloid progenitor assay. The surviving fractions of total myeloid progenitors, colony-forming cells (CFC, exposed to carbon-ion beams were significantly lower than of those exposed to X-rays, indicating that CFCs are more sensitive to carbon-ion beams (D(0 = 0.65 than to X-rays (D(0 = 1.07. Similar sensitivities were observed in granulocyte-macrophage and erythroid progenitors, respectively. However, the sensitivities of mixed-type progenitors to both radiation types were similar. In liquid culture for 14 days, no significant difference in total numbers of mononuclear cells was observed between non-irradiated control culture and cells exposed to 0.5 Gy X-rays, whereas 0.5 Gy carbon-ion beams suppressed cell proliferation to 4.9% of the control, a level similar to that for cells exposed to 1.5 Gy X-rays. Cell surface antigens associated with terminal maturation, such as CD13, CD14, and CD15, on harvest from the culture of X-ray-exposed cells were almost the same as those from the non-irradiated control culture. X-rays increased the CD235a(+ erythroid-related fraction, whereas carbon-ion beams increased the CD34(+CD38(- primitive cell fraction and the CD13(+CD14(+/-CD15(- fraction. These results suggest that carbon-ion beams inflict severe damage on the clonal growth of myeloid HSPCs, although the intensity of cell

  1. Characteristics of myeloid differentiation and maturation pathway derived from human hematopoietic stem cells exposed to different linear energy transfer radiation types.

    Science.gov (United States)

    Monzen, Satoru; Yoshino, Hironori; Kasai-Eguchi, Kiyomi; Kashiwakura, Ikuo

    2013-01-01

    Exposure of hematopoietic stem/progenitor cells (HSPCs) to ionizing radiation causes a marked suppression of mature functional blood cell production in a linear energy transfer (LET)- and/or dose-dependent manner. However, little information about LET effects on the proliferation and differentiation of HSPCs has been reported. With the aim of characterizing the effects of different types of LET radiations on human myeloid hematopoiesis, in vitro hematopoiesis in Human CD34(+) cells exposed to carbon-ion beams or X-rays was compared. Highly purified CD34(+) cells exposed to each form of radiation were plated onto semi-solid culture for a myeloid progenitor assay. The surviving fractions of total myeloid progenitors, colony-forming cells (CFC), exposed to carbon-ion beams were significantly lower than of those exposed to X-rays, indicating that CFCs are more sensitive to carbon-ion beams (D(0) = 0.65) than to X-rays (D(0) = 1.07). Similar sensitivities were observed in granulocyte-macrophage and erythroid progenitors, respectively. However, the sensitivities of mixed-type progenitors to both radiation types were similar. In liquid culture for 14 days, no significant difference in total numbers of mononuclear cells was observed between non-irradiated control culture and cells exposed to 0.5 Gy X-rays, whereas 0.5 Gy carbon-ion beams suppressed cell proliferation to 4.9% of the control, a level similar to that for cells exposed to 1.5 Gy X-rays. Cell surface antigens associated with terminal maturation, such as CD13, CD14, and CD15, on harvest from the culture of X-ray-exposed cells were almost the same as those from the non-irradiated control culture. X-rays increased the CD235a(+) erythroid-related fraction, whereas carbon-ion beams increased the CD34(+)CD38(-) primitive cell fraction and the CD13(+)CD14(+/-)CD15(-) fraction. These results suggest that carbon-ion beams inflict severe damage on the clonal growth of myeloid HSPCs, although the intensity of cell surface

  2. Myeloid-derived suppressor cell role in tumor-related inflammation.

    Science.gov (United States)

    Dolcetti, Luigi; Marigo, Ilaria; Mantelli, Barbara; Peranzoni, Elisa; Zanovello, Paola; Bronte, Vincenzo

    2008-08-28

    Chronic inflammatory state can create a proper environment for neoplastic onset and sustain cancer growth. The inflammatory state that arises at the tumor edge could contribute to immune escape phenomena in many ways. Myeloid-derived suppressor cells (MDSCs), a cell population that contributes to tumor escape, immune tolerance, and suppression, respond to a variety of pro-inflammatory and anti-inflammatory stimuli, which drive their recruitment and activation. Understanding how the inflammatory milieu favours tumor escape through the accumulation of MDSCs could be very useful to improve the efficacy of cancer immunotherapy.

  3. Myeloid cells are required for PD-1/PD-L1 checkpoint activation and the establishment of an immunosuppressive environment in pancreatic cancer

    Science.gov (United States)

    Zhang, Yaqing; Velez-Delgado, Ashley; Mathew, Esha; Li, Dongjun; Mendez, Flor M; Flannagan, Kevin; Rhim, Andrew D; Simeone, Diane M; Beatty, Gregory L; Pasca di Magliano, Marina

    2017-01-01

    Background Pancreatic cancer is characterised by the accumulation of a fibro-inflammatory stroma. Within this stromal reaction, myeloid cells are a predominant population. Distinct myeloid subsets have been correlated with tumour promotion and unmasking of anti-tumour immunity. Objective The goal of this study was to determine the effect of myeloid cell depletion on the onset and progression of pancreatic cancer and to understand the relationship between myeloid cells and T cell-mediated immunity within the pancreatic cancer microenvironment. Methods Primary mouse pancreatic cancer cells were transplanted into CD11b-diphtheria toxin receptor (DTR) mice. Alternatively, the iKras* mouse model of pancreatic cancer was crossed into CD11b-DTR mice. CD11b+ cells (mostly myeloid cell population) were depleted by diphtheria toxin treatment during tumour initiation or in established tumours. Results Depletion of myeloid cells prevented KrasG12D-driven pancreatic cancer initiation. In pre-established tumours, myeloid cell depletion arrested tumour growth and in some cases, induced tumour regressions that were dependent on CD8+ T cells. We found that myeloid cells inhibited CD8+ T-cell anti-tumour activity by inducing the expression of programmed cell death-ligand 1 (PD-L1) in tumour cells in an epidermal growth factor receptor (EGFR)/mitogen-activated protein kinases (MAPK)-dependent manner. Conclusion Our results show that myeloid cells support immune evasion in pancreatic cancer through EGFR/MAPK-dependent regulation of PD-L1 expression on tumour cells. Derailing this crosstalk between myeloid cells and tumour cells is sufficient to restore anti-tumour immunity mediated by CD8+ T cells, a finding with implications for the design of immune therapies for pancreatic cancer. PMID:27402485

  4. Myeloid cells are required for PD-1/PD-L1 checkpoint activation and the establishment of an immunosuppressive environment in pancreatic cancer.

    Science.gov (United States)

    Zhang, Yaqing; Velez-Delgado, Ashley; Mathew, Esha; Li, Dongjun; Mendez, Flor M; Flannagan, Kevin; Rhim, Andrew D; Simeone, Diane M; Beatty, Gregory L; Pasca di Magliano, Marina

    2017-01-01

    Pancreatic cancer is characterised by the accumulation of a fibro-inflammatory stroma. Within this stromal reaction, myeloid cells are a predominant population. Distinct myeloid subsets have been correlated with tumour promotion and unmasking of anti-tumour immunity. The goal of this study was to determine the effect of myeloid cell depletion on the onset and progression of pancreatic cancer and to understand the relationship between myeloid cells and T cell-mediated immunity within the pancreatic cancer microenvironment. Primary mouse pancreatic cancer cells were transplanted into CD11b-diphtheria toxin receptor (DTR) mice. Alternatively, the iKras* mouse model of pancreatic cancer was crossed into CD11b-DTR mice. CD11b(+) cells (mostly myeloid cell population) were depleted by diphtheria toxin treatment during tumour initiation or in established tumours. Depletion of myeloid cells prevented Kras(G12D)-driven pancreatic cancer initiation. In pre-established tumours, myeloid cell depletion arrested tumour growth and in some cases, induced tumour regressions that were dependent on CD8(+) T cells. We found that myeloid cells inhibited CD8(+) T-cell anti-tumour activity by inducing the expression of programmed cell death-ligand 1 (PD-L1) in tumour cells in an epidermal growth factor receptor (EGFR)/mitogen-activated protein kinases (MAPK)-dependent manner. Our results show that myeloid cells support immune evasion in pancreatic cancer through EGFR/MAPK-dependent regulation of PD-L1 expression on tumour cells. Derailing this crosstalk between myeloid cells and tumour cells is sufficient to restore anti-tumour immunity mediated by CD8(+) T cells, a finding with implications for the design of immune therapies for pancreatic cancer. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  5. Secondary Lymphoid Organ Homing Phenotype of Human Myeloid Dendritic Cells Disrupted by an Intracellular Oral Pathogen

    Science.gov (United States)

    Miles, Brodie; Zakhary, Ibrahim; El-Awady, Ahmed; Scisci, Elizabeth; Carrion, Julio; O'Neill, John C.; Rawlings, Aaron; Stern, J. Kobi; Susin, Cristiano

    2014-01-01

    Several intracellular pathogens, including a key etiological agent of chronic periodontitis, Porphyromonas gingivalis, infect blood myeloid dendritic cells (mDCs). This infection results in pathogen dissemination to distant inflammatory sites (i.e., pathogen trafficking). The alteration in chemokine-chemokine receptor expression that contributes to this pathogen trafficking function, particularly toward sites of neovascularization in humans, is unclear. To investigate this, we utilized human monocyte-derived DCs (MoDCs) and primary endothelial cells in vitro, combined with ex vivo-isolated blood mDCs and serum from chronic periodontitis subjects and healthy controls. Our results, using conditional fimbria mutants of P. gingivalis, show that P. gingivalis infection of MoDCs induces an angiogenic migratory profile. This profile is enhanced by expression of DC-SIGN on MoDCs and minor mfa-1 fimbriae on P. gingivalis and is evidenced by robust upregulation of CXCR4, but not secondary lymphoid organ (SLO)-homing CCR7. This disruption of SLO-homing capacity in response to respective chemokines closely matches surface expression of CXCR4 and CCR7 and is consistent with directed MoDC migration through an endothelial monolayer. Ex vivo-isolated mDCs from the blood of chronic periodontitis subjects, but not healthy controls, expressed a similar migratory profile; moreover, sera from chronic periodontitis subjects expressed elevated levels of CXCL12. Overall, we conclude that P. gingivalis actively “commandeers” DCs by reprogramming the chemokine receptor profile, thus disrupting SLO homing, while driving migration toward inflammatory vascular sites. PMID:24126519

  6. Derivation of a myeloid cell-binding adenovirus for gene therapy of inflammation.

    Directory of Open Access Journals (Sweden)

    Michael O Alberti

    Full Text Available The gene therapy field is currently limited by the lack of vehicles that permit efficient gene delivery to specific cell or tissue subsets. Native viral vector tropisms offer a powerful platform for transgene delivery but remain nonspecific, requiring elevated viral doses to achieve efficacy. In order to improve upon these strategies, our group has focused on genetically engineering targeting domains into viral capsid proteins, particularly those based on adenovirus serotype 5 (Ad5. Our primary strategy is based on deletion of the fiber knob domain, to eliminate broad tissue specificity through the human coxsackie-and-adenovirus receptor (hCAR, with seamless incorporation of ligands to re-direct Ad tropism to cell types that express the cognate receptors. Previously, our group and others have demonstrated successful implementation of this strategy in order to specifically target Ad to a number of surface molecules expressed on immortalized cell lines. Here, we utilized phage biopanning to identify a myeloid cell-binding peptide (MBP, with the sequence WTLDRGY, and demonstrated that MBP can be successfully incorporated into a knob-deleted Ad5. The resulting virus, Ad.MBP, results in specific binding to primary myeloid cell types, as well as significantly higher transduction of these target populations ex vivo, compared to unmodified Ad5. These data are the first step in demonstrating Ad targeting to cell types associated with inflammatory disease.

  7. Cytosine arabinoside induces costimulatory molecule expression in acute myeloid leukemia cells.

    Science.gov (United States)

    Vereecque, R; Saudemont, A; Quesnel, B

    2004-07-01

    Chemotherapeutic drugs kill cancer cells mainly by direct cytotoxicity, but they might also induce a stronger host immune response by causing the tumor to produce costimulatory cell surface molecules like CD80. We previously reported that in myeloid leukemic cells, gamma-irradiation induced CD80 expression. In this study, we show that cytosine arabinoside (Ara-C), even at low doses, induced CD80 expression in vitro in mouse DA1-3b leukemic cells, by a mechanism that involved reactive oxygen species. In vivo experiments in the mouse DA1-3b/C3H whole-animal acute myeloid leukemia (AML) model showed that injection of Ara-C induced expression of CD80 and CD86, and decreased expression of B7-H1, indicating that chemotherapy can modify costimulatory molecule expression in vivo, in a way not necessarily observed in vitro. Mouse leukemic cells exposed in vivo to Ara-C were more susceptible to specific cytotoxic lymphocyte (CTL)-mediated killing. Ara-C also induced CD80 or CD86 expression in 14 of 21 primary cultured human AML samples. In humans being treated for AML, induction chemotherapy increased CD86 expression in the leukemic cells. These findings indicate possible synergistic strategies between CTL-based immunotherapy and chemotherapy for treatment. They also suggest an additional mechanism by which chemotherapy can eradicate AML blasts.

  8. Ipilimumab and Decitabine in Treating Patients With Relapsed or Refractory Myelodysplastic Syndrome or Acute Myeloid Leukemia

    Science.gov (United States)

    2016-09-12

    Chimerism; Hematopoietic Cell Transplantation Recipient; Previously Treated Myelodysplastic Syndrome; RAEB-1; RAEB-2; Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  9. Genome-Wide CRISPR-Cas9 Screen Identifies MicroRNAs That Regulate Myeloid Leukemia Cell Growth.

    Science.gov (United States)

    Wallace, Jared; Hu, Ruozhen; Mosbruger, Timothy L; Dahlem, Timothy J; Stephens, W Zac; Rao, Dinesh S; Round, June L; O'Connell, Ryan M

    2016-01-01

    Mammalian microRNA expression is dysregulated in human cancer. However, the functional relevance of many microRNAs in the context of tumor biology remains unclear. Using CRISPR-Cas9 technology, we performed a global loss-of-function screen to simultaneously test the functions of individual microRNAs and protein-coding genes during the growth of a myeloid leukemia cell line. This approach identified evolutionarily conserved human microRNAs that suppress or promote cell growth, revealing that microRNAs are extensively integrated into the molecular networks that control tumor cell physiology. miR-155 was identified as a top microRNA candidate promoting cellular fitness, which we confirmed with two distinct miR-155-targeting CRISPR-Cas9 lentiviral constructs. Further, we performed anti-correlation functional profiling to predict relevant microRNA-tumor suppressor gene or microRNA-oncogene interactions in these cells. This analysis identified miR-150 targeting of p53, a connection that was experimentally validated. Taken together, our study describes a powerful genetic approach by which the function of individual microRNAs can be assessed on a global level, and its use will rapidly advance our understanding of how microRNAs contribute to human disease.

  10. Potential differentiation of tumor bearing mouse CD11b+Gr-1+ immature myeloid cells into both suppressor macrophages and immunostimulatory dendritic cells.

    Science.gov (United States)

    Narita, Yoshinori; Wakita, Daiko; Ohkur, Takayuki; Chamoto, Kenji; Nishimura, Takashi

    2009-02-01

    Evaluation of immunosuppressive tumor-escape mechanisms in tumor-bearing hosts is of great importance for the development of an efficient tumor immunotherapy. We document here the functional characteristics of CD11b(+)Gr-1(+) immature myeloid cells (ImC), which increase abnormally in tumor-bearing mice. Although it has been reported that ImC exhibit a strong immunosuppressive activity against T cell responses, we demonstrate that ImC derived from tumor-bearing mouse spleens (TB-SPL) did not exhibit a strong inhibitory activity against CTL generation in MLR. However, ImC isolated from TB-SPL and induced to differentiate into CD11b(+)Gr-1(+)F4/80(+) suppressor macrophages (MPhi) under the influence of tumor-derived factors were immunosuppressive. Furthermore, we also demonstrate that ImC isolated from TB-SPL had a capability of differentiating into immunostimulatory dendritic cells (DC1) supportive of the generation of IFN-gamma producing CTL if the ImC were cultured with Th1 cytokines plus GM-CSF and IL-3. Thus, our findings indicate that tumor bearing mouse-derived CD11b(+)Gr-1(+) ImC are not committed to development into immunosuppressor cells but have dual differentiation ability into both immunosuppressive myeloid cells and immunostimulatory DC1.

  11. Targeting myeloid-derived suppressor cells augments antitumor activity against lung cancer

    Directory of Open Access Journals (Sweden)

    Srivastava MK

    2012-10-01

    Full Text Available Minu K Srivastava,1,2 Li Zhu,1,2 Marni Harris-White,2 Min Huang,1–3 Maie St John,1,3 Jay M Lee,1,3 Ravi Salgia,4 Robert B Cameron,1,3,5 Robert Strieter,6 Steven Dubinett,1–3 Sherven Sharma1–31Department of Medicine, UCLA Lung Cancer Research Program, David Geffen School of Medicine at UCLA, Los Angeles, CA, 2Molecular Gene Medicine Laboratory, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, 3Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, Los Angeles, CA, 4Department of Medicine, University of Chicago, Chicago, IL, 5Department of Surgery, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, 6Department of Medicine, University of Virginia, Charlottesville, VA, USAAbstract: Lung cancer evades host immune surveillance by dysregulating inflammation. Tumors and their surrounding stromata produce growth factors, cytokines, and chemokines that recruit, expand, and/or activate myeloid-derived suppressor cells (MDSCs. MDSCs regulate immune responses and are frequently found in malignancy. In this review the authors discuss tumor-MDSC interactions that suppress host antitumor activities and the authors' recent findings regarding MDSC depletion that led to improved therapeutic vaccination responses against lung cancer. Despite the identification of a repertoire of tumor antigens, hurdles persist for immune-based anticancer therapies. It is likely that combined therapies that address the multiple immune deficits in cancer patients will be required for effective therapy. MDSCs play a major role in the suppression of T-cell activation and they sustain tumor growth, proliferation, and metastases. Regulation of MDSC recruitment, differentiation or expansion, and inhibition of the MDSC suppressive function with pharmacologic agents will be useful in the control of cancer growth and progression. Pharmacologic agents that regulate MDSCs may be more effective when combined with

  12. Small-Molecule Disruption of the Myb/p300 Cooperation Targets Acute Myeloid Leukemia Cells.

    Science.gov (United States)

    Uttarkar, Sagar; Piontek, Therese; Dukare, Sandeep; Schomburg, Caroline; Schlenke, Peter; Berdel, Wolfgang E; Müller-Tidow, Carsten; Schmidt, Thomas J; Klempnauer, Karl-Heinz

    2016-12-01

    The transcription factor c-Myb is essential for the proliferation of hematopoietic cells and has been implicated in the development of leukemia and other human cancers. Pharmacologic inhibition of Myb is therefore emerging as a potential therapeutic strategy for these diseases. By using a Myb reporter cell line, we have identified plumbagin and several naphthoquinones as potent low-molecular weight Myb inhibitors. We demonstrate that these compounds inhibit c-Myb by binding to the c-Myb transactivation domain and disrupting the cooperation of c-Myb with the coactivator p300, a major driver of Myb activity. Naphthoquinone-induced inhibition of c-Myb suppresses Myb target gene expression and induces the differentiation of the myeloid leukemia cell line HL60. We demonstrate that murine and human primary acute myeloid leukemia cells are more sensitive to naphthoquinone-induced inhibition of clonogenic proliferation than normal hematopoietic progenitor cells. Overall, our work demonstrates for the first time the potential of naphthoquinones as small-molecule Myb inhibitors that may have therapeutic potential for the treatment of leukemia and other tumors driven by deregulated Myb. Mol Cancer Ther; 15(12); 2905-15. ©2016 AACR. ©2016 American Association for Cancer Research.

  13. Glycoprotein B cleavage is important for murid herpesvirus 4 to infect myeloid cells.

    Science.gov (United States)

    Glauser, Daniel L; Milho, Ricardo; Frederico, Bruno; May, Janet S; Kratz, Anne-Sophie; Gillet, Laurent; Stevenson, Philip G

    2013-10-01

    Glycoprotein B (gB) is a conserved herpesvirus virion component implicated in membrane fusion. As with many-but not all-herpesviruses, the gB of murid herpesvirus 4 (MuHV-4) is cleaved into disulfide-linked subunits, apparently by furin. Preventing gB cleavage for some herpesviruses causes minor infection deficits in vitro, but what the cleavage contributes to host colonization has been unclear. To address this, we mutated the furin cleavage site (R-R-K-R) of the MuHV-4 gB. Abolishing gB cleavage did not affect its expression levels, glycosylation, or antigenic conformation. In vitro, mutant viruses entered fibroblasts and epithelial cells normally but had a significant entry deficit in myeloid cells such as macrophages and bone marrow-derived dendritic cells. The deficit in myeloid cells was not due to reduced virion binding or endocytosis, suggesting that gB cleavage promotes infection at a postendocytic entry step, presumably viral membrane fusion. In vivo, viruses lacking gB cleavage showed reduced lytic spread in the lungs. Alveolar epithelial cell infection was normal, but alveolar macrophage infection was significantly reduced. Normal long-term latency in lymphoid tissue was established nonetheless.

  14. Role of arginase 1 from myeloid cells in th2-dominated lung inflammation.

    Directory of Open Access Journals (Sweden)

    Luke Barron

    Full Text Available Th2-driven lung inflammation increases Arginase 1 (Arg1 expression in alternatively-activated macrophages (AAMs. AAMs modulate T cell and wound healing responses and Arg1 might contribute to asthma pathogenesis by inhibiting nitric oxide production, regulating fibrosis, modulating arginine metabolism and restricting T cell proliferation. We used mice lacking Arg1 in myeloid cells to investigate the contribution of Arg1 to lung inflammation and pathophysiology. In six model systems encompassing acute and chronic Th2-mediated lung inflammation we observed neither a pathogenic nor protective role for myeloid-expressed Arg1. The number and composition of inflammatory cells in the airways and lungs, mucus secretion, collagen deposition, airway hyper-responsiveness, and T cell cytokine production were not altered if AAMs were deficient in Arg1 or simultaneously in both Arg1 and NOS2. Our results argue that Arg1 is a general feature of alternative activation but only selectively regulates Th2 responses. Therefore, attempts to experimentally or therapeutically inhibit arginase activity in the lung should be examined with caution.

  15. Cyclo-oxygenase 2 inhibitor, nabumetone, inhibits proliferation in chronic myeloid leukemia cell lines.

    Science.gov (United States)

    Vural, Filiz; Ozcan, Mehmet Ali; Ozsan, Güner Hayri; Ateş, Halil; Demirkan, Fatih; Pişkin, Ozden; Undar, Bülent

    2005-05-01

    The anti-tumor effect of cyclo-oxygenase (COX) inhibitors has been documented in several studies. COX2 inhibitors have attracted more attention because of the fewer side-effects and the more prominent anti-tumor effects. However, experience with these drugs in hematological malignancies is limited. In our study, a potent COX2 inhibitor, nabumetone (NBT), was investigated for its anti-proliferative and apoptotic effects in K-562 and Meg-01 chronic myeloid leukemia blastic cell lines as a single agent or in combination with adriamycin (ADR) and interferon alpha (IFN-a). In these cell lines, a dose-dependent inhibition of proliferation was observed with NBT. We observed no significant apoptotic effect of NBT. However, NBT potentiated the apoptotic effect of ADR in the K-562 cell line. Bcl-2 expression was reduced by NBT (11% vs. 2%). The combination of NBT with IFN did not have any significant effect on the K-562 cell line. We suggest that NBT inhibits proliferation and potentiates the apoptotic effect of ADR in chronic myeloid leukemia cell lines.

  16. Small molecule inhibition of cAMP response element binding protein in human acute myeloid leukemia cells.

    Science.gov (United States)

    Mitton, B; Chae, H-D; Hsu, K; Dutta, R; Aldana-Masangkay, G; Ferrari, R; Davis, K; Tiu, B C; Kaul, A; Lacayo, N; Dahl, G; Xie, F; Li, B X; Breese, M R; Landaw, E M; Nolan, G; Pellegrini, M; Romanov, S; Xiao, X; Sakamoto, K M

    2016-12-01

    The transcription factor CREB (cAMP Response-Element Binding Protein) is overexpressed in the majority of acute myeloid leukemia (AML) patients, and this is associated with a worse prognosis. Previous work revealed that CREB overexpression augmented AML cell growth, while CREB knockdown disrupted key AML cell functions in vitro. In contrast, CREB knockdown had no effect on long-term hematopoietic stem cell activity in mouse transduction/transplantation assays. Together, these studies position CREB as a promising drug target for AML. To test this concept, a small molecule inhibitor of CREB, XX-650-23, was developed. This molecule blocks a critical interaction between CREB and its required co-activator CBP (CREB Binding Protein), leading to disruption of CREB-driven gene expression. Inhibition of CBP-CREB interaction induced apoptosis and cell-cycle arrest in AML cells, and prolonged survival in vivo in mice injected with human AML cells. XX-650-23 had little toxicity on normal human hematopoietic cells and tissues in mice. To understand the mechanism of XX-650-23, we performed RNA-seq, ChIP-seq and Cytometry Time of Flight with human AML cells. Our results demonstrate that small molecule inhibition of CBP-CREB interaction mostly affects apoptotic, cell-cycle and survival pathways, which may represent a novel approach for AML therapy.

  17. SET-NUP214 fusion in acute myeloid leukemia- and T-cell acute lymphoblastic leukemia-derived cell lines

    Directory of Open Access Journals (Sweden)

    Zaborski Margarete

    2009-01-01

    Full Text Available Abstract Background SET-NUP214 fusion resulting from a recurrent cryptic deletion, del(9(q34.11q34.13 has recently been described in T-cell acute lymphoblastic leukemia (T-ALL and in one case of acute myeloid leukemia (AML. The fusion protein appears to promote elevated expression of HOXA cluster genes in T-ALL and may contribute to the pathogenesis of the disease. We screened a panel of ALL and AML cell lines for SET-NUP214 expression to find model systems that might help to elucidate the cellular function of this fusion gene. Results Of 141 human leukemia/lymphoma cell lines tested, only the T-ALL cell line LOUCY and the AML cell line MEGAL expressed the SET(TAF-Iβ-NUP214 fusion gene transcript. RT-PCR analysis specifically recognizing the alternative first exons of the two TAF-I isoforms revealed that the cell lines also expressed TAF-Iα-NUP214 mRNA. Results of fluorescence in situ hybridization (FISH and array-based copy number analysis were both consistent with del(9(q34.11q34.13 as described. Quantitative genomic PCR also confirmed loss of genomic material between SET and NUP214 in both cell lines. Genomic sequencing localized the breakpoints of the SET gene to regions downstream of the stop codon and to NUP214 intron 17/18 in both LOUCY and MEGAL cells. Both cell lines expressed the 140 kDa SET-NUP214 fusion protein. Conclusion Cell lines LOUCY and MEGAL express the recently described SET-NUP214 fusion gene. Of special note is that the formation of the SET exon 7/NUP214 exon 18 gene transcript requires alternative splicing as the SET breakpoint is located downstream of the stop codon in exon 8. The cell lines are promising model systems for SET-NUP214 studies and should facilitate investigating cellular functions of the the SET-NUP214 protein.

  18. Gene expression profiling of human fibrocytic myeloid-derived suppressor cells (f-MDSCs)

    Science.gov (United States)

    Mazza, Emilia Maria Cristina; Zoso, Alessia; Mandruzzato, Susanna; Bronte, Vincenzo; Serafini, Paolo; Inverardi, Luca; Bicciato, Silvio

    2014-01-01

    Myeloid-derived suppressor cells (MDSCs) have been shown to control self-reactive and anti-graft effector T-cells in autoimmunity and transplantation, but their therapeutic use is limited by their scarce availability in the peripheral blood of tumor-free donors. We isolated and characterized a novel population of myeloid suppressor cells, named fibrocytic MDSC (f-MDSC), which are differentiated from umbilical cord blood (UCB) precursors (Zoso et al., 2014). This MDSC subset promotes regulatory T-cell expansion and induces normoglycemia in a xenogeneic model of type 1 diabetes. Here we describe in details the experimental design and the bioinformatics analyses of the gene expression dataset used to investigate the molecular mechanisms at the base of MDSC tolerogenic and suppressive properties. We also provide an R code to easily access the data and perform the quality controls and basic analyses relevant to this dataset. Raw and pre-processed data are available at Gene Expression Omnibus under accession GSE52376. PMID:26484135

  19. Gene expression profiling of human fibrocytic myeloid-derived suppressor cells (f-MDSCs

    Directory of Open Access Journals (Sweden)

    Emilia Maria Cristina Mazza

    2014-12-01

    Full Text Available Myeloid-derived suppressor cells (MDSCs have been shown to control self-reactive and anti-graft effector T-cells in autoimmunity and transplantation, but their therapeutic use is limited by their scarce availability in the peripheral blood of tumor-free donors. We isolated and characterized a novel population of myeloid suppressor cells, named fibrocytic MDSC (f-MDSC, which are differentiated from umbilical cord blood (UCB precursors (Zoso et al., 2014. This MDSC subset promotes regulatory T-cell expansion and induces normoglycemia in a xenogeneic model of type 1 diabetes. Here we describe in details the experimental design and the bioinformatics analyses of the gene expression dataset used to investigate the molecular mechanisms at the base of MDSC tolerogenic and suppressive properties. We also provide an R code to easily access the data and perform the quality controls and basic analyses relevant to this dataset. Raw and pre-processed data are available at Gene Expression Omnibus under accession GSE52376.

  20. Lysophospholipid acyltransferases and eicosanoid biosynthesis in zebrafish myeloid cells.

    Science.gov (United States)

    Zarini, Simona; Hankin, Joseph A; Murphy, Robert C; Gijón, Miguel A

    2014-10-01

    Eicosanoids derived from the enzymatic oxidation of arachidonic acid play important roles in a large number of physiological and pathological processes in humans. Many animal and cellular models have been used to investigate the intricate mechanisms regulating their biosynthesis and actions. Zebrafish is a widely used model to study the embryonic development of vertebrates. It expresses homologs of the key enzymes involved in eicosanoid production, and eicosanoids have been detected in extracts from adult or embryonic fish. In this study we prepared cell suspensions from kidney marrow, the main hematopoietic organ in fish. Upon stimulation with calcium ionophore, these cells produced eicosanoids including PGE2, LTB4, 5-HETE and, most abundantly, 12-HETE. They also produced small amounts of LTB5 derived from eicosapentaenoic acid. These eicosanoids were also produced in kidney marrow cells stimulated with ATP, and this production was greatly enhanced by preincubation with thimerosal, an inhibitor of arachidonate reacylation into phospholipids. Microsomes from these cells exhibited acyltransferase activities consistent with expression of MBOAT5/LPCAT3 and MBOAT7/LPIAT1, the main arachidonoyl-CoA:lysophospholipid acyltransferases. In summary, this work introduces a new cellular model to study the regulation of eicosanoid production through a phospholipid deacylation-reacylation cycle from a well-established, versatile vertebrate model species.

  1. IKKα Promotes Intestinal Tumorigenesis by Limiting Recruitment of M1-like Polarized Myeloid Cells

    Directory of Open Access Journals (Sweden)

    Serkan I. Göktuna

    2014-06-01

    Full Text Available The recruitment of immune cells into solid tumors is an essential prerequisite of tumor development. Depending on the prevailing polarization profile of these infiltrating leucocytes, tumorigenesis is either promoted or blocked. Here, we identify IκB kinase α (IKKα as a central regulator of a tumoricidal microenvironment during intestinal carcinogenesis. Mice deficient in IKKα kinase activity are largely protected from intestinal tumor development that is dependent on the enhanced recruitment of interferon γ (IFNγ-expressing M1-like myeloid cells. In IKKα mutant mice, M1-like polarization is not controlled in a cell-autonomous manner but, rather, depends on the interplay of both IKKα mutant tumor epithelia and immune cells. Because therapies aiming at the tumor microenvironment rather than directly at the mutated cancer cell may circumvent resistance development, we suggest IKKα as a promising target for colorectal cancer (CRC therapy.

  2. The quality and quantity of leukemia-derived dendritic cells from patients with acute myeloid leukemia and myelodysplastic syndrome are a predictive factor for the lytic potential of dendritic cells-primed leukemia-specific T cells.

    Science.gov (United States)

    Grabrucker, Christine; Liepert, Anja; Dreyig, Julia; Kremser, Andreas; Kroell, Tanja; Freudenreich, Markus; Schmid, Christoph; Schweiger, Cornelia; Tischer, Johanna; Kolb, Hans-Jochen; Schmetzer, Helga

    2010-06-01

    Adoptive immunotherapy is an important therapy option to reduce relapse rates after stem-cell transplantation in patients suffering from acute myeloid leukemia and myelodysplastic syndromes. Myeloid leukemic cells can regularly be induced to differentiate into leukemia-derived dendritic cells (DC(leu)), regaining the stimulatory capacity of professional dendritic cells (DCs) while presenting the known/unknown leukemic antigen repertoire. So far, induced antileukemic T-cell responses are variable or even mediate opposite effects. To further elicit DC/DC(leu)-induced T-cell-response patterns, we generated DC from 17 Acute myeloid leukemia (AML) and 2 myelodysplastic syndrome cases and carried out flowcytometry and (functional) nonradioactive fluorolysis assays before/after mixed lymphocyte cultures of matched (allogeneic) donor T cells (n=6), T cells prepared at relapse after stem-cell transplantation (n=4) or (autologous) patients' T cells (n=7) with blast containing mononuclear cells ("MNC") or DC(leu) ("DC"). Compared with "MNC", "DC" were better mediators of antileukemic-activity, although not in every case effective. We could define DC subtypes and cut-off proportions of DC subtypes/qualities (mature DC/DC(leu)) after "DC" priming, which were predictive for an antileukemic activity of primed T cells and the clinical course of the disease after immunotherapy (allogeneic stem-cell transplantation/donor lymphocytes infusion/therapy). In summary, our data show that the composition and quality of DC after a mixed lymphocyte culture-priming phase is predictive for a successful ex vivo antileukemic response, especially with respect to proportions of mature and leukemia-derived DC. These data contribute not only to predict DC-mediated functions or the clinical course of the diseases but also to develop and refine DC-vaccination strategies that may pave the way to develop and modify adoptive immunotherapy, especially for patients at relapse after allogeneic stem-cell

  3. Activation of PPARγ in myeloid cells promotes lung cancer progression and metastasis.

    Directory of Open Access Journals (Sweden)

    Howard Li

    Full Text Available Activation of peroxisome proliferator-activated receptor-γ (PPARγ inhibits growth of cancer cells including non-small cell lung cancer (NSCLC. Clinically, use of thiazolidinediones, which are pharmacological activators of PPARγ is associated with a lower risk of developing lung cancer. However, the role of this pathway in lung cancer metastasis has not been examined well. The systemic effect of pioglitazone was examined in two models of lung cancer metastasis in immune-competent mice. In an orthotopic model, murine lung cancer cells implanted into the lungs of syngeneic mice metastasized to the liver and brain. As a second model, cancer cells injected subcutaneously metastasized to the lung. In both models systemic administration of pioglitazone increased the rate of metastasis. Examination of tissues from the orthotopic model demonstrated increased numbers of arginase I-positive macrophages in tumors from pioglitazone-treated animals. In co-culture experiments of cancer cells with bone marrow-derived macrophages, pioglitazone promoted arginase I expression in macrophages and this was dependent on the expression of PPARγ in the macrophages. To assess the contribution of PPARγ in macrophages to cancer progression, experiments were performed in bone marrow-transplanted animals receiving bone marrow from Lys-M-Cre+/PPARγ(flox/flox mice, in which PPARγ is deleted specifically in myeloid cells (PPARγ-Mac(neg, or control PPARγ(flox/flox mice. In both models, mice receiving PPARγ-Mac(neg bone marrow had a marked decrease in secondary tumors which was not significantly altered by treatment with pioglitazone. This was associated with decreased numbers of arginase I-positive cells in the lung. These data support a model in which activation of PPARγ may have opposing effects on tumor progression, with anti-tumorigenic effects on cancer cells, but pro-tumorigenic effects on cells of the microenvironment, specifically myeloid cells.

  4. Triggering receptor expressed on myeloid cells-2 fine-tunes inflammatory responses in murine Gram-negative sepsis

    DEFF Research Database (Denmark)

    Schmidt Thøgersen, Mariane; Gawish, Riem; Martins, Rui;

    2015-01-01

    in bacterial phagocytosis. In line with this, TREM-2(-/-) peritoneal macrophages (PMs) exhibited augmented inflammation following TLR4 stimulation, demonstrating the presence and negative regulatory functionality of TREM-2 on primary PMs. Significantly, we identified a high turnover rate because TREM-2 RNA......During infections, TLR-mediated responses require tight regulation to allow for pathogen removal, while preventing overwhelming inflammation and immunopathology. The triggering receptor expressed on myeloid cells (TREM)-2 negatively regulates inflammation by macrophages and impacts on phagocytosis...... was followed by an accelerated resolution and ultimately improved survival, associated with the induction of the negative regulator A20. Upon infection with Escherichia coli, the otherwise beneficial effect of an exaggerated early immune response in TREM-2(-/-) animals was counteracted by a 50% reduction...

  5. Symptom-Adapted Physical Activity Intervention in Minimizing Physical Function Decline in Older Patients With Acute Myeloid Leukemia Undergoing Chemotherapy

    Science.gov (United States)

    2016-07-26

    Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Recurrent Adult Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  6. Activation of Myeloid-Derived Suppressor Cells in Bone Marrow

    Science.gov (United States)

    2013-12-01

    Curr Protoc Pharmacol 2010;Chapter 14:Unit14.15. 21. Jung Y, Shiozawa Y, Wang J, McGregor N, Dai J, Park SI, et al. Prevalence of prostate cancer... Wang J, Jung Y, et al. Proteoglycan 4, a novel immunomodulatory factor, regulates parathyroid hormone actions on hematopoietic cells. Am J Pathol...Nephrol 2000;11:1085–92. 36. Sabbota AL, Kim H-RC, Zhe X, Fridman R, Bonfil RD, Cher ML. Shedding of RANKL by tumor-associated MT1-MMP activates Src

  7. High-affinity FRβ-specific CAR T cells eradicate AML and normal myeloid lineage without HSC toxicity.

    Science.gov (United States)

    Lynn, R C; Feng, Y; Schutsky, K; Poussin, M; Kalota, A; Dimitrov, D S; Powell, D J

    2016-06-01

    Acute myeloid leukemia (AML) is an aggressive malignancy, and development of new treatments to prolong remissions is warranted. Chimeric antigen receptor (CAR) T-cell therapies appear promising but on-target, off-tumor recognition of antigen in healthy tissues remains a concern. Here we isolated a high-affinity (HA) folate receptor beta (FRβ)-specific single-chain variable fragment (2.48 nm KD) for optimization of FRβ-redirected CAR T-cell therapy for AML. T cells stably expressing the HA-FRβ CAR exhibited greatly enhanced antitumor activity against FRβ(+) AML in vitro and in vivo compared with a low-affinity FRβ CAR (54.3 nm KD). Using the HA-FRβ immunoglobulin G, FRβ expression was detectable in myeloid-lineage hematopoietic cells; however, expression in CD34(+) hematopoietic stem cells (HSCs) was nearly undetectable. Accordingly, HA-FRβ CAR T cells lysed mature CD14(+) monocytes, while HSC colony formation was unaffected. Because of the potential for elimination of mature myeloid lineage, mRNA CAR electroporation for transient CAR expression was evaluated. mRNA-electroporated HA-FRβ CAR T cells retained effective antitumor activity in vitro and in vivo. Together, our results highlight the importance of antibody affinity in target protein detection and CAR development and suggest that transient delivery of potent HA-FRβ CAR T cells is highly effective against AML and reduces the risk for long-term myeloid toxicity.

  8. The role of myeloid cell activation and arginine metabolism in the pathogenesis of virus-induced diseases

    Directory of Open Access Journals (Sweden)

    Kristina S. Burrack

    2014-09-01

    Full Text Available When an antiviral immune response is generated, a balance must be reached between two opposing pathways: the production of proinflammatory and cytotoxic effectors that drive a robust antiviral immune response to control the infection and regulators that function to limit or blunt an excessive immune response to minimize immune-mediated pathology and repair tissue damage. Myeloid cells, including monocytes and macrophages, play an important role in this balance, particularly through the activities of the arginine-hydrolyzing enzymes nitric oxide synthase 2 (Nos2; iNOS and arginase 1 (Arg1. Nitric oxide (NO production by iNOS is an important proinflammatory mediator, whereas Arg1-expressing macrophages contribute to the resolution of inflammation and wound repair. In the context of viral infections, expression of these enzymes can result in a variety of outcomes for the host. NO has direct antiviral properties against some viruses, whereas during other virus infections NO can mediate immunopathology and/or inhibit the antiviral immune response to promote chronic infection. Arg1 activity has important wound healing functions but can also inhibit the antiviral immune response during some viral infections. Thus, depending on the specific virus and the tissue(s involved, the activity of both of these arginine-hydrolyzing enzymes can either exacerbate or limit the severity of virus-induced disease. In this review, we will discuss a variety of viral infections, including HIV, SARS-CoV, LCMV, HCV, RSV, and others, where myeloid cells influence the control and clearance of the virus from the host, as well as the severity and resolution of tissue damage, via the activities of iNOS and/or Arg1. Clearly, monocyte/macrophage activation and arginine metabolism will continue to be important areas of investigation in the context of viral infections.

  9. Myeloid Cell Sirtuin-1 Expression Does Not Alter Host Immune Responses to Gram-Negative Endotoxemia or Gram-Positive Bacterial Infection

    Science.gov (United States)

    Crotty Alexander, Laura E.; Marsh, Brenda J.; Timmer, Anjuli M.; Lin, Ann E.; Zainabadi, Kayvan; Czopik, Agnieszka; Guarente, Leonard; Nizet, Victor

    2013-01-01

    The role of sirtuin-1 (SIRT1) in innate immunity, and in particular the influence of SIRT1 on antimicrobial defense against infection, has yet to be reported but is important to define since SIRT1 inhibitors are being investigated as therapeutic agents in the treatment of cancer, Huntington’s disease, and autoimmune diseases. Given the therapeutic potential of SIRT1 suppression, we sought to characterize the role of SIRT1 in host defense. Utilizing both pharmacologic methods and a genetic knockout, we demonstrate that SIRT1 expression has little influence on macrophage and neutrophil antimicrobial functions. Myeloid SIRT1 expression does not change mortality in gram-negative toxin-induced shock or gram-positive bacteremia, suggesting that therapeutic suppression of SIRT1 may be done safely without suppression of myeloid cell-specific immune responses to severe bacterial infections. PMID:24386389

  10. Myeloid cell sirtuin-1 expression does not alter host immune responses to Gram-negative endotoxemia or Gram-positive bacterial infection.

    Directory of Open Access Journals (Sweden)

    Laura E Crotty Alexander

    Full Text Available The role of sirtuin-1 (SIRT1 in innate immunity, and in particular the influence of SIRT1 on antimicrobial defense against infection, has yet to be reported but is important to define since SIRT1 inhibitors are being investigated as therapeutic agents in the treatment of cancer, Huntington's disease, and autoimmune diseases. Given the therapeutic potential of SIRT1 suppression, we sought to characterize the role of SIRT1 in host defense. Utilizing both pharmacologic methods and a genetic knockout, we demonstrate that SIRT1 expression has little influence on macrophage and neutrophil antimicrobial functions. Myeloid SIRT1 expression does not change mortality in gram-negative toxin-induced shock or gram-positive bacteremia, suggesting that therapeutic suppression of SIRT1 may be done safely without suppression of myeloid cell-specific immune responses to severe bacterial infections.

  11. Short Stat5-interacting peptide derived from phospholipase C-β3 inhibits hematopoietic cell proliferation and myeloid differentiation.

    Directory of Open Access Journals (Sweden)

    Hiroki Yasudo

    Full Text Available Constitutive activation of the transcription factor Stat5 in hematopoietic stem/progenitor cells leads to various hematopoietic malignancies including myeloproliferative neoplasm (MPN. Our recent study found that phospholipase C (PLC-β3 is a novel tumor suppressor involved in MPN, lymphoma and other tumors. Stat5 activity is negatively regulated by the SH2 domain-containing protein phosphatase SHP-1 in a PLC-β3-dependent manner. PLC-β3 can form the multimolecular SPS complex together with SHP-1 and Stat5. The close physical proximity of SHP-1 and Stat5 brought about by interacting with the C-terminal segment of PLC-β3 (PLC-β3-CT accelerates SHP-1-mediated dephosphorylation of Stat5. Here we identify the minimal sequences within PLC-β3-CT required for its tumor suppressor function. Two of the three Stat5-binding noncontiguous regions, one of which also binds SHP-1, substantially inhibited in vitro proliferation of Ba/F3 cells. Surprisingly, an 11-residue Stat5-binding peptide (residues 988-998 suppressed Stat5 activity in Ba/F3 cells and in vivo proliferation and myeloid differentiation of hematopoietic stem/progenitor cells. Therefore, this study further defines PLC-β3-CT as the Stat5- and SHP-1-binding domain by identifying minimal functional sequences of PLC-β3 for its tumor suppressor function and implies their potential utility in the control of hematopoietic malignancies.

  12. Exogenous interleukin-33 targets myeloid-derived suppressor cells and generates periphery-induced Foxp3+ regulatory T cells in skin-transplanted mice

    Science.gov (United States)

    Gajardo, Tania; Morales, Rodrigo A; Campos-Mora, Mauricio; Campos-Acuña, Javier; Pino-Lagos, Karina

    2015-01-01

    Interleukin-33 (IL-33) has been a focus of study because of its variety of functions shaping CD4+ T-cell biology. In the present work, we evaluated the modulatory effect of IL-33 on suppressor cells in an in vivo transplantation model. C57BL/6 wild-type mice were grafted with syngeneic or allogeneic skin transplants and treated with exogenous IL-33 daily. After 10 days of treatment, we analysed draining lymph node cellularity and found in allogeneic animals an increment in myeloid-derived suppressor cells, which co-express MHC-II, and become enriched upon IL-33 treatment. In line with this observation, inducible nitric oxide synthase and arginase 1 expression were also increased in allogeneic animals upon IL-33 administration. In addition, IL-33 treatment up-regulated the number of Foxp3+ regulatory T (Treg) cells in the allogeneic group, complementing the healthier integrity of the allografts and the increased allograft survival. Moreover, we demonstrate that IL-33 promotes CD4+ T-cell expansion and conversion of CD4+ Foxp3− T cells into CD4+ Foxp3+ Treg cells in the periphery. Lastly, the cytokine pattern of ex vivo-stimulated draining lymph nodes indicates that IL-33 dampens interferon-γ and IL-17 production, stimulating IL-10 secretion. Altogether, our work complements previous studies on the immune-modulatory activity of IL-33, showing that this cytokine affects myeloid-derived suppressor cells at the cell number and gene expression levels. More importantly, our research demonstrates for the first time that IL-33 allows for in vivo Foxp3+ Treg cell conversion and favours an anti-inflammatory or tolerogenic state by skewing cytokine production. Therefore, our data suggest a potential use of IL-33 to prevent allograft rejection, bringing new therapeutics to the transplantation field. PMID:25988395

  13. In vitro evaluation of triazenes: DNA cleavage, antibacterial activity and cytotoxicity against acute myeloid leukemia cells

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    Domingues, Vanessa O.; Hoerner, Rosmari; Reetz, Luiz G.B.; Kuhn, Fabio, E-mail: rosmari.ufsm@gmail.co [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Dept. de Analises Clinicas e Toxicologicas; Coser, Virginia M.; Rodrigues, Jacqueline N.; Bauchspiess, Rita; Pereira, Waldir V. [Hospital Universitario de Santa Maria, RS (Brazil). Dept. de Hematologia-Oncologia; Paraginski, Gustavo L.; Locatelli, Aline; Fank, Juliana de O.; Giglio, Vinicius F.; Hoerner, Manfredo, E-mail: hoerner.manfredo@gmail.co [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Dept. de Quimica

    2010-07-01

    The asymmetric diazoamines 1-(2-chlorophenyl)-3-(4-carboxyphenyl)triazene (1), 1-(2-fluorophenyl)-3-(4-carboxyphenyl)triazene (2) and 1-(2-fluorophenyl)-3-(4-amidophenyl) triazene (3) were evaluated for their ability to cleave pUC18 and pBSKII plasmid DNA, antibacterial activity and in vitro cytotoxicity against acute myeloid leukemia cells and normal leukocytes using the bioassay of reduction of 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The triazenes showed ability to cleave the two types of plasmid DNA: triazene 1 at pH 8.0 and 50 deg C; triazene 2 at pH 6.5 and 37 and 50 deg C; triazene 3 at pH 6.5 and 37 deg C. The compounds presented cytotoxic activity against myeloid leukemia cells. Compound 1 showed high activity against B. cereus (MIC = 32 {mu}g mL{sup -1}). The observation of intermolecular hydrogen bonding in the solid state of compound 3, based on the structural analysis by X-ray crystallography, as well as the results of IR and UV-Vis spectroscopic analyses of compounds 1, 2 and 3 are discussed in the present work. (author)

  14. Regeneration-associated WNT Signaling Is Activated in Long-term Reconstituting AC133bright Acute Myeloid Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Alessandro Beghini

    2012-12-01

    Full Text Available Acute myeloid leukemia (AML is a genetically heterogeneous clonal disorder characterized by two molecularly distinct self-renewing leukemic stem cell (LSC populations most closely related to normal progenitors and organized as a hierarchy. A requirement for WNT/β-catenin signaling in the pathogenesis of AML has recently been suggested by a mouse model. However, its relationship to a specific molecular function promoting retention of self-renewing leukemia-initiating cells (LICs in human remains elusive. To identify transcriptional programs involved in the maintenance of a self-renewing state in LICs, we performed the expression profiling in normal (n = 10 and leukemic (n = 33 human long-term reconstituting AC133+ cells, which represent an expanded cell population in most AML patients. This study reveals the ligand-dependent WNT pathway activation in AC133bright AML cells and shows a diffuse expression and release of WNT10B, a hematopoietic stem cell regenerative-associated molecule. The establishment of a primary AC133+ AML cell culture (A46 demonstrated that leukemia cells synthesize and secrete WNT ligands, increasing the levels of dephosphorylated β-catenin in vivo. We tested the LSC functional activity in AC133+ cells and found significant levels of engraftment upon transplantation of A46 cells into irradiated Rag2-/-γc-/- mice. Owing to the link between hematopoietic regeneration and developmental signaling, we transplanted A46 cells into developing zebrafish. This system revealed the formation of ectopic structures by activating dorsal organizer markers that act downstream of the WNT pathway. In conclusion, our findings suggest that AC133bright LSCs are promoted by misappropriating homeostatic WNT programs that control hematopoietic regeneration.

  15. Matrix metalloproteinase-9 was involved in the immuno-modulatory defect of mesenchymal stem cell from chronic myeloid leukemia patients

    Institute of Scientific and Technical Information of China (English)

    ZHU Xi-shan; SHI Wei; AN Guang-yu; ZHANG Hong-mei; SONG Yu-guang; LI You-bin

    2011-01-01

    Background Overwhelming evidences on chronic myeloid leukemia (CML) indicate that patients harbor quiescent CML stem cells that are responsible for blast crisis. While the hematopoietic stem cell (HSC) origin of CML was first suggested over 30 years ago, recently CML-initiating cells beyond HSCs are also being investigated.Methods We have previously isolated fetal liver kinase-1-positive (Flk1+) cells carrying the BCR/ABL fusion gene from the bone marrow of Ph+ patients with hemangioblast property. In this study, we isolated CML patient-derived regulation using fluorescence in situ hybridization (FISH) analysis, fluorescence activated cell sorting (FACS),enzyme-linked immunoadsorbent assay, mixed lymphocyte reaction assays; then we compared these characters with those of the healthy donors.lymphocyte activation and proliferation was impaired in vitro.Conclusions CML patient-derived MSCs have impaired immuno-modulatory functions, suggesting that the dysregulation of hematopoiesis and immune response may originate from MSCs rather than hematopoietic stem cells (HSCs). MSCs might be a potential target for developing efficacious treatment for CML.

  16. Real-time imaging of myeloid cells dynamics in ApcMin/+ intestinal tumors by spinning disk confocal microscopy.

    Science.gov (United States)

    Bonnans, Caroline; Lohela, Marja; Werb, Zena

    2014-10-06

    Myeloid cells are the most abundant immune cells within tumors and have been shown to promote tumor progression. Modern intravital imaging techniques enable the observation of live cellular behavior inside the organ but can be challenging in some types of cancer due to organ and tumor accessibility such as intestine. Direct observation of intestinal tumors has not been previously reported. A surgical procedure described here allows direct observation of myeloid cell dynamics within the intestinal tumors in live mice by using transgenic fluorescent reporter mice and injectable tracers or antibodies. For this purpose, a four-color, multi-region, micro-lensed spinning disk confocal microscope that allows long-term continuous imaging with rapid image acquisition has been used. Apc(Min/+) mice that develop multiple adenomas in the small intestine are crossed with c-fms-EGFP mice to visualize myeloid cells and with ACTB-ECFP mice to visualize intestinal epithelial cells of the crypts. Procedures for labeling different tumor components, such as blood vessels and neutrophils, and the procedure for positioning the tumor for imaging through the serosal surface are also described. Time-lapse movies compiled from several hours of imaging allow the analysis of myeloid cell behavior in situ in the intestinal microenvironment.

  17. Myeloid cell-derived hypoxia-inducible factor attenuates inflammation in unilateral ureteral obstruction-induced kidney injury.

    Science.gov (United States)

    Kobayashi, Hanako; Gilbert, Victoria; Liu, Qingdu; Kapitsinou, Pinelopi P; Unger, Travis L; Rha, Jennifer; Rivella, Stefano; Schlöndorff, Detlef; Haase, Volker H

    2012-05-15

    Renal fibrosis and inflammation are associated with hypoxia, and tissue pO(2) plays a central role in modulating the progression of chronic kidney disease. Key mediators of cellular adaptation to hypoxia are hypoxia-inducible factor (HIF)-1 and -2. In the kidney, they are expressed in a cell type-specific manner; to what degree activation of each homolog modulates renal fibrogenesis and inflammation has not been established. To address this issue, we used Cre-loxP recombination to activate or to delete both Hif-1 and Hif-2 either globally or cell type specifically in myeloid cells. Global activation of Hif suppressed inflammation and fibrogenesis in mice subjected to unilateral ureteral obstruction, whereas activation of Hif in myeloid cells suppressed inflammation only. Suppression of inflammatory cell infiltration was associated with downregulation of CC chemokine receptors in renal macrophages. Conversely, global deletion or myeloid-specific inactivation of Hif promoted inflammation. Furthermore, prolonged hypoxia suppressed the expression of multiple inflammatory molecules in noninjured kidneys. Collectively, we provide experimental evidence that hypoxia and/or myeloid cell-specific HIF activation attenuates renal inflammation associated with chronic kidney injury.

  18. Decitabine, Donor Natural Killer Cells, and Aldesleukin in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

    Science.gov (United States)

    2016-01-07

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia

  19. Distinct mechanisms of regulation of the ITGA6 and ITGB4 genes by RUNX1 in myeloid cells.

    Science.gov (United States)

    Phillips, Jessica L; Taberlay, Phillippa C; Woodworth, Alexandra M; Hardy, Kristine; Brettingham-Moore, Kate H; Dickinson, Joanne L; Holloway, Adele F

    2017-09-19

    Integrins are transmembrane adhesion receptors that play an important role in hematopoiesis by facilitating interactions between hematopoietic cells and extracellular matrix components of the bone marrow and hematopoietic tissues. These interactions are important in regulating the function, proliferation and differentiation of hematopoietic cells, as well as their homing and mobilization in the bone marrow. Not surprisingly altered expression and function of integrins plays a key role in the development and progression of cancer including leukemias. However, the regulation of integrin gene expression is not well characterized and the mechanisms by which integrin genes are disrupted in cancer remain unclear. Here we demonstrate for the first time that a key regulator of hematopoiesis, RUNX1, binds to and regulates the promoters of both the ITGA6 and ITGB4 genes in myeloid cells. The ITGA6 and ITGB4 integrin genes form the α6β4 integrin receptor. However our data indicates that RUNX1 functions differently at these two promoters. RUNX1 regulates ITGA6 through a consensus RUNX1 binding motif in its promoter. In contrast, although the ITGB4 promoter is also activated by RUNX1, it does so in the absence of a recognized consensus RUNX1 binding motif. Further, our data suggest that regulation of ITGB4 may involve interactions between the promoter and upstream regulatory elements. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  20. Kruppel-like factor KLF4 facilitates cutaneous wound healing by promoting fibrocyte generation from myeloid-derived suppressor cells.

    Science.gov (United States)

    Ou, Lingling; Shi, Ying; Dong, Wenqi; Liu, Chunming; Schmidt, Thomas J; Nagarkatti, Prakash; Nagarkatti, Mitzi; Fan, Daping; Ai, Walden

    2015-05-01

    Pressure ulcers (PUs) are serious skin injuries whereby the wound healing process is frequently stalled in the inflammatory phase. Myeloid-derived suppressor cells (MDSCs) accumulate as a result of inflammation and promote cutaneous wound healing by mechanisms that are not fully understood. Recently, MDSCs have been shown to differentiate into fibrocytes, which serve as emerging effector cells that enhance cell proliferation in wound healing. We postulate that in wound healing MDSCs not only execute their immunosuppressive function to regulate inflammation but also stimulate cell proliferation once they differentiate into fibrocytes. In the current study, by using full-thickness and PU mouse models, we found that Kruppel-like factor 4 (KLF4) deficiency resulted in decreased accumulation of MDSCs and fibrocytes, and wound healing was significantly delayed. Conversely, KLF4 activation by the plant-derived product Mexicanin I increased the number of MDSCs and fibrocytes and accelerated the wound healing. Collectively, our study revealed a previously unreported function of MDSCs in cutaneous wound healing and identified Mexicanin I as a potential agent to accelerate PU wound healing.

  1. Phenotypically resembling myeloid derived suppressor cells are increased in children with HIV and exposed/infected with Mycobacterium tuberculosis.

    Science.gov (United States)

    Du Plessis, Nelita; Jacobs, Ruschca; Gutschmidt, Andrea; Fang, Zhuo; van Helden, Paul D; Lutz, Manfred B; Hesseling, Anneke C; Walzl, Gerhard

    2017-01-01

    Increased disease susceptibility during early life has been linked to immune immaturity, regulatory T-cell/TH2 immune biasing and hyporesponsiveness. The contribution of myeloid derived suppressor cells (MDSCs) remains uninvestigated. Here, we assessed peripheral MDSC in HIV-infected and -uninfected children with tuberculosis (TB) disease before, during and after TB treatment, along with matched household contacts (HHCs), HIV-exposed, -infected and -uninfected children without recent TB exposure. Serum analytes and enzymes associated with MDSC accumulation/activation/function were measured by colorimetric- and fluorescence arrays. Peripheral frequencies of cells phenotypically resembling MDSCs were significantly increased in HIV-exposed uninfected (HEU) and M.tb-infected children, but peaked in children with TB disease and remained high following treatment. MDSC in HIV-infected (HI) children were similar to unexposed uninfected controls; however, HAART-mediated MDSC restoration to control levels could not be disregarded. Increased MDSC frequencies in HHC coincided with enhanced indoleamine-pyrrole-2,3-dioxygenase (IDO), whereas increased MDSC in TB cases were linked to heightened IDO and arginase-1. Increased MDSC were paralleled by reduced plasma IP-10 and thrombospondin-2 levels in HEU and significantly increased plasma IL-6 in HI HHC. Current investigations into MDSC-targeted treatment strategies, together with functional analyses of MDSCs, could endorse these cells as novel innate immune regulatory mechanism of infant HIV/TB susceptibility. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Time-series analysis in imatinib-resistant chronic myeloid leukemia K562-cells under different drug treatments.

    Science.gov (United States)

    Zhao, Yan-Hong; Zhang, Xue-Fang; Zhao, Yan-Qiu; Bai, Fan; Qin, Fan; Sun, Jing; Dong, Ying

    2017-08-01

    Chronic myeloid leukemia (CML) is characterized by the accumulation of active BCR-ABL protein. Imatinib is the first-line treatment of CML; however, many patients are resistant to this drug. In this study, we aimed to compare the differences in expression patterns and functions of time-series genes in imatinib-resistant CML cells under different drug treatments. GSE24946 was downloaded from the GEO database, which included 17 samples of K562-r cells with (n=12) or without drug administration (n=5). Three drug treatment groups were considered for this study: arsenic trioxide (ATO), AMN107, and ATO+AMN107. Each group had one sample at each time point (3, 12, 24, and 48 h). Time-series genes with a ratio of standard deviation/average (coefficient of variation) >0.15 were screened, and their expression patterns were revealed based on Short Time-series Expression Miner (STEM). Then, the functional enrichment analysis of time-series genes in each group was performed using DAVID, and the genes enriched in the top ten functional categories were extracted to detect their expression patterns. Different time-series genes were identified in the three groups, and most of them were enriched in the ribosome and oxidative phosphorylation pathways. Time-series genes in the three treatment groups had different expression patterns and functions. Time-series genes in the ATO group (e.g. CCNA2 and DAB2) were significantly associated with cell adhesion, those in the AMN107 group were related to cellular carbohydrate metabolic process, while those in the ATO+AMN107 group (e.g. AP2M1) were significantly related to cell proliferation and antigen processing. In imatinib-resistant CML cells, ATO could influence genes related to cell adhesion, AMN107 might affect genes involved in cellular carbohydrate metabolism, and the combination therapy might regulate genes involved in cell proliferation.

  3. The Kasumi-1 cell line: a t(8;21)-kit mutant model for acute myeloid leukemia.

    Science.gov (United States)

    Larizza, Lidia; Magnani, Ivana; Beghini, Alessandro

    2005-02-01

    The Kasumi-1 cell line is an intensively investigated model system of Acute Myeloid Leukemia with t(8;21) translocation, that represents 1 of the 2 main subtypes of Core Binding Factor Leukemia (CBFL). Since establishment in 1991 the Kasumi-1 cell line has provided the tool to study the peculiar molecular, morphologic, immunophenotypic findings of AML with t(8;21) and the functional consequences of the AML1-ETO fusion oncogene on myeloid differentiation. Leukemogenesis involves multiple genetic changes and, as suggested by murine experiments and other findings in humans, AML1-ETO expression may not be sufficient for full blown leukemia. In agreement with the "two hits" model of leukemogenesis, based on the cooperation between 1 class of mutations that impair hematopoietic differentiation and a second class of mutations that confer a proliferative and/or survival advantage to hematopoietic progenitors an activating mutation in the tyrosine kinase domain of the c-kit gene was identified in the AML1/ETO expressing Kasumi-1 cell line. The dosage of the Asn822Lys mutated allele was shown to be about 5-fold compared to the normal allele and c-kit amplification was found to map to minute 4cen-q11 marker chromosomes, likely derived from the extra chromosome 4 recorded in the newly established cell line. The combination of t(8;21) and trisomy 4 leading to enhanced dosage of a mutated kit allele is a feature of a few CBFL patients reproduced by the Kasumi-1 cell model. The Kasumi-1 cell line, paralleling the commitment stage of CBF leukemia also provides a valuable resource to investigate the effect of tyrosine kinase kit mutant on the main KIT-regulated signal transduction pathways, i.e. MAPK, PI3K/AKT and STAT3 and the diverse inhibitory effect exerted by STI 571 on these KIT mutant activated pathways. PI3K-dependent activation of AKT and STAT activation was observed in Kasumi-1 cells. Contrary to the expectations for an amplified tyrosine kinase kit mutant, we found that

  4. Gr-1⁺CD11b⁺ immature myeloid cells (IMC) promote resistance of pro-inflammatory T cells to suppression by regulatory T cells in atherosclerotic Apo E- deficient mice.

    Science.gov (United States)

    Chen, Yulin; Jian, Ying; Liu, Minjie; Zhong, Liang; Zhang, Fang; Yang, Weifeng; Xu, Zhao; Chen, Guofan; Liu, Yuhua

    2014-01-01

    Accumulating evidence indicates that both defects in Treg numbers and/or function as well as resistance of effector T cells to suppression may contribute to the development of human chronic inflammatory diseases. However, which mechanism involved in the progression of atherosclerosis remains unclear. In this study, we evaluated the production and function of CD4⁺ inflammatory and regulatory T cells in atherosclerosis-prone mice. We found that the hyperactivity and unresponsiveness to Treg-mediated suppression of inflammatory CD4⁺ T cells occurred in the progression of atherosclerosis, though Treg cells were present in very large numbers and fully functional. We further found that Gr-1⁺CD11b⁺ immature myeloid cells were significantly accumulated in atherosclerotic Apo E⁻/⁻ mice, and they promoted resistance of inflammatory CD4⁺ T cells to Treg-mediated suppression in vitro and in vivo. we further confirmed that Gr-1⁺CD11b⁺ immature myeloid cells produced high level of interleukin 6 which was at least partially responsible for inducing unresponsiveness of inflammatory CD4⁺ T cells to suppression via activation of Jak/Stat signaling pathway. Taken together, these findings might provide new insights to explore potential targets for immune therapeutic intervention in atherosclerosis.

  5. Identification of a myeloid-derived suppressor cell cystatin-like protein that inhibits metastasis.

    Science.gov (United States)

    Boutté, Angela M; Friedman, David B; Bogyo, Matthew; Min, Yongfen; Yang, Li; Lin, P Charles

    2011-08-01

    Myeloid-derived suppressor cells (MDSCs) are significantly increased in cancer patients and tumor bearing-animals. MDSCs infiltrate into tumors and promote tumor invasion and metastasis. To identify the mediator responsible for the prometastatic property of MDSCs, we used proteomics. We found neutrophilic granule protein (NGP) was decreased >2-fold in MDSCs from metastatic 4T1 tumor-bearing mice compared to nonmetastatic 67NR controls. NGP mRNA levels were decreased in bone marrow and in tumor-infiltrating MDSCs by 45 and 66%, respectively, in 4T1 tumor-bearing mice compared to 67NR controls. Interestingly, 4T1-conditioned medium reduced myeloid cell NGP expression by ∼ 40%, suggesting that a secreted factor mediates gene reduction. Sequence analysis shows a putative cystatin domain in NGP, and biochemical analysis confirms NGP a novel cathepsin inhibitor. It inhibited cathepsin B activity by nearly 40% in vitro. NGP expression in 4T1 tumor cells suppressed cell invasion, delayed primary tumor growth, and greatly reduced lung metastasis in vivo. A 2.8-fold reduction of cathepsin activity was found in tumors expressing NGP compared to controls. NGP significantly reduced tumor angiogenesis to 12.6 from 19.6 and lymphangiogenesis to 4.6 from 9.1 vessels/field. Necrosis was detectable only in NGP-expressing tumors, and the number of apoptotic cells increased to 22.4 from 8.3 in controls. Taken together, this study identifies a negative regulator of tumor metastasis in MDSCs, NGP, which is down-regulated in metastatic conditions. The finding suggests that malignant tumors promote invasion/metastasis not only through up-regulation of proteases but also down-regulation of protease inhibitors.

  6. Caffeic acid phenethyl ester induces mitochondria-mediated apoptosis in human myeloid leukemia U937 cells.

    Science.gov (United States)

    Jin, Un-Ho; Song, Kwon-Ho; Motomura, Muneo; Suzuki, Ikukatsu; Gu, Yeun-Hwa; Kang, Yun-Jeong; Moon, Tae-Chul; Kim, Cheorl-Ho

    2008-03-01

    Caffeic acid phenyl ester (CAPE), a biologically active ingredient of propolis, has several interesting biological properties including antioxidant, anti-inflammatory, antiviral, immunostimulatory, anti-angiogenic, anti-invasive, anti-metastatic and carcinostatic activities. Recently, several groups have reported that CAPE is cytotoxic to tumor cells but not to normal cells. In this study, we investigated the mechanism of CAPE-induced apoptosis in human myeloid leukemia U937 cells. Treatment of U937 cells with CAPE decreased cell viability in a dose-dependent and time-dependent manner. DNA fragmentation assay revealed the typical ladder profile of oligonucleosomal fragments in CAPE-treated U937 cells. In addition, as evidenced by the nuclear DAPI staining experiment, we observed that the nuclear condensation, a typical phenotype of apoptosis, was found in U937 cells treated with 5 microg/ml of CAPE. Therefore, it was suggested that CAPE is a potent agent inducing apoptosis in U937 cells. Apoptotic action of the CAPE was accompanied by release of cytochrome C, reduction of Bcl-2 expression, increase of Bax expression, activation/cleavage of caspase-3 and activation/cleavage of PARP in U937 cells, but not by Fas protein, an initial mediator in the death signaling, or by phospho-eIF2 alpha and CHOP, crucial mediators in ER-mediated apoptosis. From the results, it was concluded that CAPE induces the mitochondria-mediated apoptosis but not death receptors- or ER-mediated apoptosis in U937 cells.

  7. Recombinant human IL-3 and G-CSF act synergistically in stimulating the growth of acute myeloid leukemia cells.

    Science.gov (United States)

    Pébusque, M J; Faÿ, C; Lafage, M; Sempéré, C; Saeland, S; Caux, C; Mannoni, P

    1989-03-01

    The effects of combinations of recombinant human growth factors (colony-stimulating factor (CSF], interleukin 3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and granulocyte colony stimulating factor (G-CSF) for inducing proliferation of leukemic cells were compared in 27 acute myeloid leukemias (AMLs). While functional heterogeneity of AML was clearly shown, we further demonstrated that optimal growth may be obtained with combinations of CSF. The most striking feature was that, in both suspension and semisolid cultures, IL-3 and G-CSF acted synergistically in supporting AML cell proliferation except in cases for which G-CSF was found to be an inhibitory factor. In the majority of cases, the proliferative effects of the IL-3 and GM-CSF combination were significantly higher than the most potent of either factor present alone in the cultures. Finally, preincubation with IL-3 greatly potentiated the responsiveness of AML cells to subsequent addition of either GM-CSF or G-CSF. These results indicate that AML cells respond to growth factor in the same way as normal hemopoietic cells and that stimulation by a second late-acting growth factor such as G-CSF is also required to yield optimal growth.

  8. The Effects of T4 and A3/R Bacteriophages on Differentiation of Human Myeloid Dendritic Cells.

    Science.gov (United States)

    Bocian, Katarzyna; Borysowski, Jan; Zarzycki, Michał; Pacek, Magdalena; Weber-Dąbrowska, Beata; Machcińska, Maja; Korczak-Kowalska, Grażyna; Górski, Andrzej

    2016-01-01

    Bacteriophages (phages) are viruses of bacteria. Here we evaluated the effects of T4 and A3/R bacteriophages, as well as phage-generated bacterial lysates, on differentiation of human myeloid dendritic cells (DCs) from monocytes. Neither of the phages significantly reduced the expression of markers associated with differentiation of DCs and their role in the activation of T cells (CD40, CD80, CD83, CD86, CD1c, CD11c, MHC II, PD-L1, PD-L2, TLR2, TLR4, and CCR7) and phagocytosis receptors (CD64 and DEC-205). By contrast, bacterial lysate of T4 phage significantly decreased the percentages of DEC-205- and CD1c-positive cells. The percentage of DEC-205-positive cells was also significantly reduced in DCs differentiated in the presence of lysate of A3/R phage. Thus while bacteriophages do not substantially affect differentiation of DCs, some products of phage-induced lysis of bacterial cells may influence the differentiation and potentially also some functions of DCs. Our results have important implications for phage therapy of bacterial infections because during infections monocytes recruited to the site of inflammation are an important source of inflammatory DCs.

  9. The effects of T4 and A3R bacteriophages on differentiation of human myeloid dendritic cells

    Directory of Open Access Journals (Sweden)

    Katarzyna Bocian

    2016-08-01

    Full Text Available Bacteriophages (phages are viruses of bacteria. Here we evaluated the effects of T4 and A3R bacteriophages, as well as phage-generated bacterial lysates, on differentiation of human myeloid dendritic cells (DCs from monocytes. Neither of the phages significantly reduced the expression of markers associated with differentiation of DCs and their role in the activation of T cells (CD40, CD80, CD83, CD86, CD1c, CD11c, MHC II, PD-L1, PD-L2, TLR2, TLR4, and CCR7 and phagocytosis receptors (CD64 and DEC-205. By contrast, bacterial lysate of T4 phage significantly decreased the percentages of DEC-205- and CD1c-positive cells. The percentage of DEC-205-positive cells was also significantly reduced in DCs differentiated in the presence of lysate of A3R phage. Thus while bacteriophages do not substantially affect differentiation of DCs, some products of phage-induced lysis of bacterial cells may influence the differentiation and potentially also some functions of DCs. Our results have important implications for phage therapy of bacterial infections because during infections monocytes recruited to the site of inflammation are an important source of inflammatory DCs.

  10. The Effects of T4 and A3/R Bacteriophages on Differentiation of Human Myeloid Dendritic Cells

    Science.gov (United States)

    Bocian, Katarzyna; Borysowski, Jan; Zarzycki, Michał; Pacek, Magdalena; Weber-Dąbrowska, Beata; Machcińska, Maja; Korczak-Kowalska, Grażyna; Górski, Andrzej

    2016-01-01

    Bacteriophages (phages) are viruses of bacteria. Here we evaluated the effects of T4 and A3/R bacteriophages, as well as phage-generated bacterial lysates, on differentiation of human myeloid dendritic cells (DCs) from monocytes. Neither of the phages significantly reduced the expression of markers associated with differentiation of DCs and their role in the activation of T cells (CD40, CD80, CD83, CD86, CD1c, CD11c, MHC II, PD-L1, PD-L2, TLR2, TLR4, and CCR7) and phagocytosis receptors (CD64 and DEC-205). By contrast, bacterial lysate of T4 phage significantly decreased the percentages of DEC-205- and CD1c-positive cells. The percentage of DEC-205-positive cells was also significantly reduced in DCs differentiated in the presence of lysate of A3/R phage. Thus while bacteriophages do not substantially affect differentiation of DCs, some products of phage-induced lysis of bacterial cells may influence the differentiation and potentially also some functions of DCs. Our results have important implications for phage therapy of bacterial infections because during infections monocytes recruited to the site of inflammation are an important source of inflammatory DCs. PMID:27582733

  11. Triggering receptor expressed on myeloid cells-1 (TREM-1) amplifies the signals induced by the NACHT-LRR (NLR) pattern recognition receptors.

    NARCIS (Netherlands)

    Netea, M.G.; Azam, T.; Ferwerda, G.; Girardin, S.E.; Kim, S.H.; Dinarello, C.A.

    2006-01-01

    Triggering receptor expressed on myeloid cells-1 (TREM-1) is a member of a new family of myeloid receptors, encoded by a gene cluster linked to the MHC. Engagement of TREM-1 stimulates intracellular signals, resulting in activation of phagocytosis, neutrophil degranulation, and amplification of cyto

  12. Secondary Philadelphia chromosome and erythrophagocytosis in a relapsed acute myeloid leukemia after hematopoietic cell transplantation.

    Science.gov (United States)

    Kelemen, Katalin; Galani, Komal; Conley, Christopher R; Greipp, Patricia T

    2014-06-01

    The acquisition of the Philadelphia chromosome (Ph) as a secondary change during the course of hematopoietic malignancies is rare and is associated with poor prognosis. Few cases of secondary Ph have been reported after hematopoietic cell transplantation (HCT). A secondary Ph at relapse is of clinical importance because it provides a therapeutic target for tyrosine kinase inhibitors along with or in replacement of chemotherapy. We describe a case of relapsed acute myeloid leukemia (AML) after HCT that developed a BCR-ABL1 translocation along with erythrophagocytosis by blasts as a secondary change at the time of relapse. The progression of this patient's myeloid neoplasm from myelodysplastic syndrome to AML to relapsed AML after HCT was accompanied by a stepwise cytogenetic evolution: A deletion 20q abnormality subsequently acquired a deletion 7q and, finally, at relapse after HCT, a secondary Ph was gained. The relationship between the secondary Ph and the erythrophagocytosis by blasts is not clear. We review the possible pathogenesis and cytogenetic associations of erythrophagocytosis by blasts, a rare feature in acute leukemias.

  13. Gr-1intCD11b+ myeloid-derived suppressor cells accumulate in corneal allograft and improve corneal allograft survival.

    Science.gov (United States)

    Choi, Wungrak; Ji, Yong Woo; Ham, Hwa-Yong; Yeo, Areum; Noh, Hyemi; Jin, Su-Eon; Song, Jong Suk; Kim, Hyeon Chang; Kim, Eung Kwon; Lee, Hyung Keun

    2016-12-01

    We identified the characteristics of myeloid-derived suppressor cells (MDSCs) and investigated their mechanism of induction and their functional role in allograft rejection using a murine corneal allograft model. In mice, MDSCs coexpress CD11b and myeloid differentiation antigen Gr-1. Gr-1(+)CD11b(+) cells infiltrated allografted corneas between 4 d and 4 wk after surgery; however, the frequencies of Gr-1(+)CD11b(+) cells were not different between accepted and rejected allografts or in peripheral blood or BM. Of interest, Gr-1(int)CD11b(+) cells, but not Gr-1(hi)CD11b(+) cells, infiltrated the accepted graft early after surgery and expressed high levels of immunosuppressive cytokines, including IL-10, TGF-β, and TNF-related apoptosis-inducing ligand. This population remained until 4 wk after surgery. In vitro, only high dose (>100 ng/ml) of IFN-γ plus GM-CSF could induce immunosuppressive cytokine expression in Gr-1(int)CD11b(+) cells. Furthermore, adoptive transfer of Gr-1(int)CD11b(+) cells reduced T cell infiltration, which improved graft survival. In conclusion, high-dose IFN-γ in allograft areas is essential for development of Gr-1(int)CD11b(+) MDSCs in corneal allografts, and subtle environmental changes in the early period of the allograft can result in a large difference in graft survival.

  14. T Cells Encountering Myeloid Cells Programmed for Amino Acid-dependent Immunosuppression Use Rictor/mTORC2 Protein for Proliferative Checkpoint Decisions.

    Science.gov (United States)

    Van de Velde, Lee-Ann; Subramanian, Chitra; Smith, Amber M; Barron, Luke; Qualls, Joseph E; Neale, Geoffrey; Alfonso-Pecchio, Adolfo; Jackowski, Suzanne; Rock, Charles O; Wynn, Thomas A; Murray, Peter J

    2017-01-06

    Modulation of T cell proliferation and function by immunoregulatory myeloid cells are an essential means of preventing self-reactivity and restoring tissue homeostasis. Consumption of amino acids such as arginine and tryptophan by immunoregulatory macrophages is one pathway that suppresses local T cell proliferation. Using a reduced complexity in vitro macrophage-T cell co-culture system, we show that macrophage arginase-1 is the only factor required by M2 macrophages to block T cells in G1, and this effect is mediated by l-arginine elimination rather than metabolite generation. Tracking how T cells adjust their metabolism when deprived of arginine revealed the significance of macrophage-mediated arginine deprivation to T cells. We found mTORC1 activity was unaffected in the initial G1 block. After 2 days of arginine deprivation, mTORC1 activity declined paralleling a selective down-regulation of SREBP target gene expression, whereas mRNAs involved in glycolysis, gluconeogenesis, and T cell activation were unaffected. Cell cycle arrest was reversible at any point by exogenous arginine, suggesting starved T cells remain poised awaiting nutrients. Arginine deprivation-induced cell cycle arrest was mediated in part by Rictor/mTORC2, providing evidence that this nutrient recognition pathway is a central component of how T cells measure environmental arginine. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Tet2 facilitates the derepression of myeloid target genes during CEBPα-induced transdifferentiation of pre-B cells

    DEFF Research Database (Denmark)

    Kallin, Eric M; Rodríguez-Ubreva, Javier; Christensen, Jesper Aagaard

    2012-01-01

    The methylcytosine hydroxylase Tet2 has been implicated in hematopoietic differentiation and the formation of myeloid malignancies when mutated. An ideal system to study the role of Tet2 in myelopoeisis is CEBPα-induced transdifferentiation of pre-B cells into macrophages. Here we found that CEBP...

  16. An Anti-EGFR IgA That Displays Improved Pharmacokinetics and Myeloid Effector Cell Engagement In Vivo

    NARCIS (Netherlands)

    Lohse, Stefan; Meyer, Saskia; Meulenbroek, Laura A P M; Jansen, J H Marco; Nederend, Maaike; Kretschmer, Anna; Klausz, Katja; Möginger, Uwe; Derer, Stefanie; Rösner, Thies; Kellner, Christian; Schewe, Denis; Sondermann, Peter; Tiwari, Sanjay; Kolarich, Daniel; Peipp, Matthias; Leusen, Jeanette H W; Valerius, Thomas

    2016-01-01

    Antibodies of IgA isotype effectively engage myeloid effector cells for cancer immunotherapy. Here, we describe preclinical studies with an Fc engineered IgA2m(1) antibody containing the variable regions of the EGFR antibody cetuximab. Compared with wild-type IgA2m(1), the engineered molecule lacked

  17. Myeloid Cell Prostaglandin E2 Receptor EP4 Modulates Cytokine Production but Not Atherogenesis in a Mouse Model of Type 1 Diabetes.

    Directory of Open Access Journals (Sweden)

    Sara N Vallerie

    Full Text Available Type 1 diabetes mellitus (T1DM is associated with cardiovascular complications induced by atherosclerosis. Prostaglandin E2 (PGE2 is often raised in states of inflammation, including diabetes, and regulates inflammatory processes. In myeloid cells, a key cell type in atherosclerosis, PGE2 acts predominately through its Prostaglandin E Receptor 4 (EP4; Ptger4 to modulate inflammation. The effect of PGE2-mediated EP4 signaling specifically in myeloid cells on atherosclerosis in the presence and absence of diabetes is unknown. Because diabetes promotes atherosclerosis through increased arterial myeloid cell accumulation, we generated a myeloid cell-targeted EP4-deficient mouse model (EP4M-/- of T1DM-accelerated atherogenesis to investigate the relationship between myeloid cell EP4, inflammatory phenotypes of myeloid cells, and atherogenesis. Diabetic mice exhibited elevated plasma PGE metabolite levels and elevated Ptger4 mRNA in macrophages, as compared with non-diabetic littermates. PGE2 increased Il6, Il1b, Il23 and Ccr7 mRNA while reducing Tnfa mRNA through EP4 in isolated myeloid cells. Consistently, the stimulatory effect of diabetes on peritoneal macrophage Il6 was mediated by PGE2-EP4, while PGE2-EP4 suppressed the effect of diabetes on Tnfa in these cells. In addition, diabetes exerted effects independent of myeloid cell EP4, including a reduction in macrophage Ccr7 levels and increased early atherogenesis characterized by relative lesional macrophage accumulation. These studies suggest that this mouse model of T1DM is associated with increased myeloid cell PGE2-EP4 signaling, which is required for the stimulatory effect of diabetes on IL-6, markedly blunts the effect of diabetes on TNF-α and does not modulate diabetes-accelerated atherogenesis.

  18. Bisphenol A (BPA) stimulates the interferon signaling and activates the inflammasome activity in myeloid cells.

    Science.gov (United States)

    Panchanathan, Ravichandran; Liu, Hongzhu; Leung, Yuet-Kin; Ho, Shuk-mei; Choubey, Divaker

    2015-11-05

    Environmental factors contribute to the development of autoimmune diseases, including systemic lupus erythematosus (SLE), which exhibits a strong female bias (female-to-male ratio 9:1). However, the molecular mechanisms remain largely unknown. Because a feedforward loop between the female sex hormone estrogen (E2) and type I interferon (IFN-α/β)-signaling induces the expression of certain p200-family proteins (such as murine p202 and human IFI16) that regulate innate immune responses and modify lupus susceptibility, we investigated whether treatment of myeloid cells with bisphenol A (BPA), an environmental estrogen, could regulate the p200-family proteins and activate innate immune responses. We found that treatment of murine bone marrow-derived cells (BMCs) and human peripheral blood mononuclear cells with BPA induced the expression of ERα and IFN-β, activated the IFN-signaling, and stimulated the expression of the p202 and IFI16 proteins. Further, the treatment increased levels of the NLRP3 inflammasome and stimulated its activity. Accordingly, BPA-treatment of BMCs from non lupus-prone C57BL/6 and the lupus-prone (NZB×NZW)F1 mice activated the type I IFN-signaling, induced the expression of p202, and activated an inflammasome activity. Our study demonstrates that BPA-induced signaling in the murine and human myeloid cells stimulates the type I IFN-signaling that results in an induction of the p202 and IFI16 innate immune sensors for the cytosolic DNA and activates an inflammasome activity. These observations provide novel molecular insights into the role of environmental BPA exposures in potentiating the development of certain autoimmune diseases such as SLE.

  19. Asynchronous expression of myeloid antigens in leukemic cells in a PML/RARalpha transgenic mouse model

    Directory of Open Access Journals (Sweden)

    B.A.A. Santana

    2006-05-01

    Full Text Available Acute promyelocytic leukemia (APL is characterized by the expansion of blasts that resemble morphologically promyelocytes and harbor a chromosomal translocation involving the retinoic acid receptor a (RARa and the promyelocytic leukemia (PML genes on chromosomes 17 and 15, respectively. The expression of the PML/RARa fusion gene is essential for APL genesis. In fact, transgenic mice (TM expressing PML/RARa develop a form of leukemia that mimics the hematological findings of human APL. Leukemia is diagnosed after a long latency (approximately 12 months during which no hematological abnormality is detected in peripheral blood (pre-leukemic phase. In humans, immunophenotypic analysis of APL blasts revealed distinct features; however, the precise immunophenotype of leukemic cells in the TM model has not been established. Our aim was to characterize the expression of myeloid antigens by leukemic cells from hCG-PML/RARa TM. In this study, TM (N = 12 developed leukemia at the mean age of 13.1 months. Morphological analysis of bone marrow revealed an increase of the percentage of immature myeloid cells in leukemic TM compared to pre-leukemic TM and wild-type controls (48.63 ± 16.68, 10.83 ± 8.11, 7.4 ± 5.46%, respectively; P < 0.05. Flow cytometry analysis of bone marrow and spleen from leukemic TM identified the asynchronous co-expression of CD34, CD117, and CD11b. This abnormal phenotype was rarely detected prior to the diagnosis of leukemia and was present at similar frequencies in hematologically normal TM and wild-type controls of different ages. The present results demonstrate that, similarly to human APL, leukemic cells from hCG-PML/RARa TM present a specific immunophenotype.

  20. Inhibition of myeloid cell differentiation in cancer: the role of reactive oxygen species.

    Science.gov (United States)

    Kusmartsev, Sergei; Gabrilovich, Dmitry I

    2003-08-01

    It is well established that tumor growth is associated with accumulation of immature myeloid cells (ImC). They play an important role in tumor-associated immune suppression. ImC accumulate not only in tumor-bearing hosts but also in immunized, tumor-free hosts or hosts infected with bacterial pathogens. The kinetics of ImC in these mice is different. If in tumor-bearing mice, the number of ImC continues to increase with tumor progression in tumor-free mice after an initial spike, it decreases to the control level. Here, we have investigated the mechanisms of ImC accumulation in tumor-bearing hosts by comparing differentiation of ImC obtained from tumor-free and tumor-bearing mice. In the presence of appropriate growth factors, ImC isolated from tumor-free mice quickly differentiated in vitro into mature dendritic cells (DC), macrophages, and granulocytes. In contrast, differentiation of ImC from tumor-bearing mice was significantly delayed. Similar results were obtained in vivo after adoptive transfer of ImC into naïve, congeneic mice. ImC transferred into tumor-bearing recipients failed to differentiate into DC or macrophages. ImC from tumor-bearing mice had significantly higher levels of reactive oxygen species (ROS) than ImC obtained from tumor-free mice. Hydrogen peroxide (H(2)O(2)) but not superoxide radical anions was found to be the major part of this increased ROS production. In vitro experiments demonstrated that scavenging of H(2)O(2) with catalase induced differentiation of ImC from tumor-bearing mice into macrophages. Thus, this is a first demonstration that tumors may prevent differentiation of antigen-presenting cells by increasing the level of endogenous H(2)O(2) in immature myeloid cells.

  1. Activated factor X signaling via protease-activated receptor 2 suppresses pro-inflammatory cytokine production from LPS-stimulated myeloid cells.

    LENUS (Irish Health Repository)

    Gleeson, Eimear M

    2013-07-19

    Vitamin K-dependent proteases generated in response to vascular injury and infection enable fibrin clot formation, but also trigger distinct immuno-regulatory signaling pathways on myeloid cells. Factor Xa, a protease crucial for blood coagulation, also induces protease-activated receptor-dependent cell signaling. Factor Xa can bind both monocytes and macrophages, but whether factor Xa-dependent signaling stimulates or suppresses myeloid cell cytokine production in response to Toll-like receptor activation is not known. In this study, exposure to factor Xa significantly impaired pro-inflammatory cytokine production from lipopolysaccharide-treated peripheral blood mononuclear cells, THP-1 monocytic cells and murine macrophages. Furthermore, factor Xa inhibited nuclear factor-kappa B activation in THP-1 reporter cells, requiring phosphatidylinositide 3-kinase activity for its anti-inflammatory effect. Active-site blockade, γ-carboxyglutamic acid domain truncation and a peptide mimic of the factor Xa inter-epidermal growth factor-like region prevented factor Xa inhibition of lipopolysaccharide-induced tumour necrosis factor-α release. In addition, factor Xa anti-inflammatory activity was markedly attenuated by the presence of an antagonist of protease-activated receptor 2, but not protease-activated receptor 1. The key role of protease-activated receptor 2 in eliciting factor Xa-dependent anti-inflammatory signaling on macrophages was further underscored by the inability of factor Xa to mediate inhibition of tumour necrosis factor-α and interleukin-6 release from murine bone marrow-derived protease-activated receptor 2-deficient macrophages. We also show for the first time that, in addition to protease-activated receptor 2, factor Xa requires a receptor-associated protein-sensitive low-density lipoprotein receptor to inhibit lipopolysaccharide-induced cytokine production. Collectively, this study supports a novel function for factor Xa as an endogenous, receptor

  2. Complement regulates conventional DC-mediated NK-cell activation by inducing TGF-β1 in Gr-1+ myeloid cells.

    Science.gov (United States)

    Qing, Xiaoping; Koo, Gloria C; Salmon, Jane E

    2012-07-01

    Complement activation modulates DC-mediated T-cell activation, but whether complement affects DC-mediated priming of NK cells is unknown. Here, we demonstrated that conventional DCs (cDCs) from C3(-/-) and C5aR(-/-) mice are hyperresponsive to polyI:C, a TLR3 ligand, leading to enhanced NK-cell activation. We found that cDCs lack C5a receptor (C5aR) and do not respond to C5a directly. Depletion of Gr-1(+) myeloid cells augments polyI:C-induced cDC activation in WT but not in C3(-/-) or C5aR(-/-) mice, indicating that the effect of complement activation on cDCs is indirectly mediated through C5aR-expressing Gr-1(+) myeloid cells. We further demonstrated that the mechanism by which Gr-1(+) myeloid cells regulate the activity of cDCs involves C5a-dependent TGF-β1 production in Gr-1(+) myeloid cells. C5a enhances and blocking C5aR decreases TGF-β1 production in cultured bone marrow Gr-1(+) CD11b(+) cells. C5aR deficiency is associated with reduced circulating TGF-β1 levels, while depleting Gr-1(+) myeloid cells abrogates this difference between WT and C5aR(-/-) mice. Lastly, we showed that enhanced cDC-NK-cell activity in C3(-/-) mice led to delayed melanoma tumor growth. Thus, complement activation indirectly regulates cDC-NK-cell activation in response to inflammatory stimuli such as TLR3 by promoting TGF-β1 production in Gr-1(+) myeloid cells at steady state.

  3. Cytotoxic activity to acute myeloid leukemia cells by Antp-TPR hybrid peptide targeting Hsp90.

    Science.gov (United States)

    Horibe, Tomohisa; Kawamoto, Megumi; Kohno, Masayuki; Kawakami, Koji

    2012-07-01

    We previously reported that Antp-TPR hybrid peptide inhibited the interaction of Hsp90 with TPR2A and had selective cytotoxic activity discriminating between normal and cancer cells to induce cancer cell death. In this study, we investigated the cytotoxic activity of Antp-TPR peptide toward acute myeloid leukemia (AML) cells. It was demonstrated that Antp-TPR peptide induced AML cell death in cell lines such as U937, K562, THP-1, and HL-60 via activation of caspases 3 and 7, and disruption of mitochondrial membrane potential. Conversely, Antp-TPR peptide did not reduce the viability of normal cells including peripheral blood mononuclear cells (PBMCs), although both geldanamycin and 17-AAG, small-molecule inhibitors of Hsp90, mediated cytotoxicity to these normal cells at low concentrations. In addition, mutation analysis of TPR peptide demonstrated that the highly conserved amino acids Lys and Arg were critical to the cytotoxic activity. These results indicated that Antp-TPR hybrid peptide would provide potent and selective therapeutic options in the treatment of AML.

  4. FT-infrared spectroscopic studies of lymphoma, lymphoid, and myeloid leukemia cell lines

    Science.gov (United States)

    Babrah, Jaspreet; McCarthy, Keith P.; Lush, Richard; Rye, Adam D.; Bessant, Conrad; Stone, Nicholas

    2007-07-01

    This paper presents a novel method to characterise spectral differences that distinguish leukaemia and lymphoma cell lines. This is based on objective spectral measurements of major cellular biochemical constituents and multivariate spectral processing. Fourier transform infrared (FT-IR) maps of the lymphoma, lymphoid and myeloid leukaemia cell samples were obtained using a Perkin-Elmer Spotlight 300 FT-IR imaging spectrometer. Multivariate statistical techniques incorporating principal component analysis (PCA) and linear discriminant analysis (LDA) were used to construct a mathematical model. This model was validated for reproducibility. Multivariate statistical analysis of FTIR spectra collected for each cell sample permit a combination of unsupervised and supervised methods of distinguishing cell line types. This resulted in the clustering of cell line populations, indicating distinct bio-molecular differences. Major spectral differences were observed in the 4000 to 800 cm -1 spectral region. Bands in the averaged spectra for the cell line were assigned to the major biochemical constituents including; proteins, fatty acids, carbohydrates and nucleic acids. The combination of FT-IR spectroscopy and multivariate statistical analysis provides an important insight into the fundamental spectral differences between the cell lines, which differ according to the cellular biochemical composition. These spectral differences can serve as potential biomarkers for the differentiation of leukaemia and lymphoma cells. Consequently these differences could be used as the basis for developing a spectral method for the detection and identification of haematological malignancies.

  5. Multiple helminth infection of the skin causes lymphocyte hypo-responsiveness mediated by Th2 conditioning of dermal myeloid cells.

    Directory of Open Access Journals (Sweden)

    Peter C Cook

    2011-03-01

    Full Text Available Infection of the mammalian host by schistosome larvae occurs via the skin, although nothing is known about the development of immune responses to multiple exposures of schistosome larvae, and/or their excretory/secretory (E/S products. Here, we show that multiple (4x exposures, prior to the onset of egg laying by adult worms, modulate the skin immune response and induce CD4(+ cell hypo-responsiveness in the draining lymph node, and even modulate the formation of hepatic egg-induced granulomas. Compared to mice exposed to a single infection (1x, dermal cells from multiply infected mice (4x, were less able to support lymph node cell proliferation. Analysis of dermal cells showed that the most abundant in 4x mice were eosinophils (F4/80(+MHC-II(-, but they did not impact the ability of antigen presenting cells (APC to support lymphocyte proliferation to parasite antigen in vitro. However, two other cell populations from the dermal site of infection appear to have a critical role. The first comprises arginase-1(+, Ym-1(+ alternatively activated macrophage-like cells, and the second are functionally compromised MHC-II(hi cells. Through the administration of exogenous IL-12 to multiply infected mice, we show that these suppressive myeloid cell phenotypes form as a consequence of events in the skin, most notably an enrichment of IL-4 and IL-13, likely resulting from an influx of RELMα-expressing eosinophils. We further illustrate that the development of these suppressive dermal cells is dependent upon IL-4Rα signalling. The development of immune hypo-responsiveness to schistosome larvae and their effect on the subsequent response to the immunopathogenic egg is important in appreciating how immune responses to helminth infections are modulated by repeated exposure to the infective early stages of development.

  6. Th17 cells and interleukin-17 increase with poor prognosis in patients with acute myeloid leukemia.

    Science.gov (United States)

    Han, Yixiang; Ye, Aifang; Bi, Laixi; Wu, Jianbo; Yu, Kang; Zhang, Shenghui

    2014-08-01

    Although Th17 cells play crucial roles in the pathogenesis of many autoimmune and inflammatory disorders, their roles in malignancies are currently under debate. The role and mechanism of Th17 cells in patients with acute myeloid leukemia (AML) remain poorly understood. Here we demonstrated that the frequency of Th17 cells was significantly increased in peripheral blood mononuclear cells (PBMCs) and bone marrow mononuclear cells from AML patients compared with healthy donors. Plasma levels of interleukin (IL)-17, IL-22, IL-23, IL-1β, IL-6, and transforming growth factor (TGF)-β1 were significantly increased in blood and bone marrow in AML patients compared with healthy donors. The in vitro experiments demonstrated that IL-1β, IL-6, IL-23, but not TGF-β1 promoted the generation and differentiation of Th17 cells from naive CD4(+) T cells in humans. IL-17A, a signature cytokine secreted by Th17 cells, induced the proliferation of IL-17 receptor (IL-17R)-positive AML cells via IL-17R, in which activation of PI3K/Akt and Jak/Stat3 signaling pathway may play important roles. In addition, combination of IL-17A and IL-22 significantly reduced the generation of Th1 cells and the production of interferon (IFN)-γ from healthy donor or AML patient peripheral blood mononuclear cells. Patients with high Th17 cell frequency had poor prognosis, whereas patients with high Th1 cell frequency had prolonged survival. Combined analysis of Th1 and Th17 cell frequencies improved the ability to predict patient outcomes. In conclusion, Th17 cells play a crucial role in the pathogenesis of AML and may be an important therapeutic target and prognostic predictor.

  7. CCR5 in recruitment and activation of myeloid-derived suppressor cells in melanoma.

    Science.gov (United States)

    Umansky, Viktor; Blattner, Carolin; Gebhardt, Christoffer; Utikal, Jochen

    2017-08-01

    Malignant melanoma is characterized by the development of chronic inflammation in the tumor microenvironment, leading to the accumulation of myeloid-derived suppressor cells (MDSCs). Using ret transgenic mouse melanoma model, we found a significant migration of MDSCs expressing C-C chemokine receptor (CCR)5 into primary tumors and metastatic lymph nodes, which was correlated with tumor progression. An increased CCR5 expression on MDSCs was associated with elevated concentrations of CCR5 ligands in melanoma microenvironment. In vitro experiments showed that the upregulation of CCR5 expression on CD11b(+)Gr1(+) immature myeloid cells was induced by CCR5 ligands, IL-6, GM-CSF, and other inflammatory factors. Furthermore, CCR5(+) MDSCs infiltrating melanoma lesions displayed a stronger immunosuppressive pattern than their CCR5(-) counterparts. Targeting CCR5/CCR5 ligand signaling via a fusion protein mCCR5-Ig, which selectively binds and neutralizes all three CCR5 ligands, increased the survival of tumor-bearing mice. This was associated with a reduced migration and immunosuppressive potential of tumor MDSCs. In melanoma patients, circulating CCR5(+) MDSCs were increased as compared to healthy donors. Like in melanoma-bearing mice, we observed an enrichment of these cells and CCR5 ligands in tumors as compared to the peripheral blood. Our findings define a critical role for CCR5 not only in the recruitment but also in the activation of MDSCs in tumor lesions, suggesting that novel strategies of melanoma treatment could be based on blocking CCR5/CCR5 ligand interactions.

  8. Isolated central nervous system relapse of chronic myeloid leukemia after allogeneic hematopoietic stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Fuchs Mary

    2012-08-01

    Full Text Available Abstract Background This case report highlights the relevance of quantifying the BCR-ABL gene in cerebrospinal fluid of patients with suspected relapse of chronic myeloid leukemia in the central nervous system. Case presentation We report on a female patient with isolated central nervous system relapse of chronic myeloid leukemia (CML during peripheral remission after allogeneic hematopoietic stem cell transplantation. The patient showed a progressive cognitive decline as the main symptom. MRI revealed a hydrocephalus and an increase in cell count in the cerebrospinal fluid (CSF with around 50% immature blasts in the differential count. A highly elevated BCR-ABL/ ABL ratio was detected in the CSF, whilst the ratio for peripheral blood and bone marrow was not altered. On treatment of the malresorptive hydrocephalus with shunt surgery, the patient showed an initial cognitive improvement, followed by a secondary deterioration. At this time, the cranial MRI showed leukemic infiltration of lateral ventricles walls. Hence, intrathecal administration of cytarabine, methotrexate, and dexamethasone was initiated, which caused a significant decrease of cells in the CSF. Soon after, the patient demonstrated significant cognitive improvement with a good participation in daily activities. At a later time point, after the patient had lost the major molecular response of CML, therapy with dasatinib was initiated. In a further follow-up, the patient was neurologically and hematologically stable. Conclusions In patients with treated CML, the rare case of an isolated CNS blast crisis has to be taken into account if neurological symptoms evolve. The analysis of BCR-ABL in the CSF is a further option for the reliable detection of primary isolated relapse of CML in these patients.

  9. Expression of soluble triggering receptor expression on myeloid cells-1 in pleural effusion

    Institute of Scientific and Technical Information of China (English)

    HUANG Lu-ying; SHI Huan-zhong; LIANG Qiu-li; WU Yan-bin; QIN Xue-jun; CHEN Yi-qiang

    2008-01-01

    Background Tdggedng receptors expressed on myeloid cells(TREM)proteins are a family of cell surface receptors expressed broadly by cells of the myeloid lineage.The aim of this study was to investigate the clinical significance of soluble TREM-1(sTREM-1)in pleural effusions,and to determine the effects of pneumonia on pleural sTREM-1 concentrations.Methods PleuraI fluid was collected from 109 patients who presented to the respiratory institute (35 with malignant pleural effusion,31 with tuberculous pleural effusion,21 with bacteriaI pleural effusion,and 22 with transudate).The concentrations of sTREM-1,tumor necrosis factor-o(TNF-α)and interleukin-1β(IL-1β)were determined jn effusion and serum samples by enzyme Iinked immunosorbent assay(ELISA).Results The concentrations of sTREM-1 in bacterial pleural effusion were significantly higher than those in malignant.tuberculous,and transudative groups(all P<0.001).An sTREM-1 cutoff value of 768.1 ng/L had a sensitivity of 86%and a specificity of 93%.Pleural sTREM-1 Ievels were positively correlated with Ievels of TNF-α and IL-1β.Patients with complicating bacterial pneumonia did not have elevated concentration of STREM-1 jn pleural effusion when compared with patients without pneumonia.Conclusions Determination of pleural sTREM-1 may improve the ability of clinicians to differentiate pleural effusion patients of bacterial origin from those with other etiologies.The occurrence of bacterial pneumonia did not affect pleural sTREM-1 concentrations.

  10. Myeloid-derived suppressor cells (MDSC) facilitate distant metastasis of malignancies by shielding circulating tumor cells (CTC) from immune surveillance.

    Science.gov (United States)

    Liu, Qiaofei; Liao, Quan; Zhao, Yupei

    2016-02-01

    The mechanisms of distant metastasis of malignancies largely remain unknown. Circulating tumor cells (CTC) derived from the primary cancer initiate distant metastasis by entering and traversing the bloodstream. Current methods to detect CTC are based on the notion that CTC do not express the common leukocyte antigen CD45. However, these methods neglect the fact that CTC can directly adhere to platelets and immune cells and therefore appear to be CD45-positive. The potential effects of interactions between CTC and adhesive immune cells have been largely overlooked, despite the fact that most CTC are killed by immune effector cells and only those that evade immune surveillance result in clonal expansion and metastatic lesions. It is crucial to define the characteristics that allow a select CTC population to escape immune surveillance; particularly, it must be determined whether interactions between CTC and adhesive immune cells provide a protective effect on CTC survival. If interactions between CTC and adhesive immune cells offer a selective advantage to those CTC cells, the next consideration is which characteristics of a CTC-immune cell population allow sufficient protection to facilitate immune evasion. Myeloid-derived suppressor cells (MDSC) are a large heterogeneous population of immature myeloid cells that accumulate during cancer progression to induce extensively systemic and local immunosuppression, a phenomenon that has been demonstrated to facilitate cancer distant metastasis. We hypothesize, therefore, that CTC populations interacting with adhesive immune cells will have different biological behavior than CTC populations alone. Further, we hypothesize that CTC can create a defensive shield consisting of adhesive MDSC, which allows evasion of immune surveillance and therefore facilitates distant metastatic lesions. This possibility highlights the importance of direct interactions between CTC and adhesive immune cells and suggests the potential target that

  11. Myeloid clusters are associated with a pro-metastatic environment and poor prognosis in smoking-related early stage non-small cell lung cancer.

    Directory of Open Access Journals (Sweden)

    Wang Zhang

    Full Text Available BACKGROUND: This study aimed to understand the role of myeloid cell clusters in uninvolved regional lymph nodes from early stage non-small cell lung cancer patients. METHODS: Uninvolved regional lymph node sections from 67 patients with stage I-III resected non-small cell lung cancer were immunostained to detect myeloid clusters, STAT3 activity and occult metastasis. Anthracosis intensity, myeloid cluster infiltration associated with anthracosis and pSTAT3 level were scored and correlated with patient survival. Multivariate Cox regression analysis was performed with prognostic variables. Human macrophages were used for in vitro nicotine treatment. RESULTS: CD68+ myeloid clusters associated with anthracosis and with an immunosuppressive and metastasis-promoting phenotype and elevated overall STAT3 activity were observed in uninvolved lymph nodes. In patients with a smoking history, myeloid cluster score significantly correlated with anthracosis intensity and pSTAT3 level (P<0.01. Nicotine activated STAT3 in macrophages in long-term culture. CD68+ myeloid clusters correlated and colocalized with occult metastasis. Myeloid cluster score was an independent prognostic factor (P = 0.049 and was associated with survival by Kaplan-Maier estimate in patients with a history of smoking (P = 0.055. The combination of myeloid cluster score with either lymph node stage or pSTAT3 level defined two populations with a significant difference in survival (P = 0.024 and P = 0.004, respectively. CONCLUSIONS: Myeloid clusters facilitate a pro-metastatic microenvironment in uninvolved regional lymph nodes and associate with occult metastasis in early stage non-small cell lung cancer. Myeloid cluster score is an independent prognostic factor for survival in patients with a history of smoking, and may present a novel method to inform therapy choices in the adjuvant setting. Further validation studies are warranted.

  12. EVI1 inhibits apoptosis induced by antileukemic drugs via upregulation of CDKN1A/p21/WAF in human myeloid cells.

    Directory of Open Access Journals (Sweden)

    Anna Rommer

    Full Text Available Overexpression of ecotropic viral integration site 1 (EVI1 is associated with aggressive disease in acute myeloid leukemia (AML. Despite of its clinical importance, little is known about the mechanism through which EVI1 confers resistance to antileukemic drugs. Here, we show that a human myeloid cell line constitutively overexpressing EVI1 after infection with a retroviral vector (U937_EVI1 was partially resistant to etoposide and daunorubicin as compared to empty vector infected control cells (U937_vec. Similarly, inducible expression of EVI1 in HL-60 cells decreased their sensitivity to daunorubicin. Gene expression microarray analyses of U937_EVI1 and U937_vec cells cultured in the absence or presence of etoposide showed that 77 and 419 genes were regulated by EVI1 and etoposide, respectively. Notably, mRNA levels of 26 of these genes were altered by both stimuli, indicating that EVI1 regulated genes were strongly enriched among etoposide regulated genes and vice versa. One of the genes that were induced by both EVI1 and etoposide was CDKN1A/p21/WAF, which in addition to its function as a cell cycle regulator plays an important role in conferring chemotherapy resistance in various tumor types. Indeed, overexpression of CDKN1A in U937 cells mimicked the phenotype of EVI1 overexpression, similarly conferring partial resistance to antileukemic drugs.

  13. Instructive role of M-CSF on commitment of bipotent myeloid cells involves ERK-dependent positive and negative signaling.

    Science.gov (United States)

    Carras, Sylvain; Valayer, Alexandre; Moratal, Claudine; Weiss-Gayet, Michèle; Pages, Gilles; Morlé, François; Mouchiroud, Guy; Gobert, Stéphanie

    2016-02-01

    M-CSF and G-CSF are instructive cytokines that specifically induce differentiation of bipotent myeloid progenitors into macrophages and granulocytes, respectively. Through morphology and colony assay studies, flow cytometry analysis of specific markers, and expression of myeloid transcription factors, we show here that the Eger/Fms cell line is composed of cells whose differentiation fate is instructed by M-CSF and G-CSF, thus representing a good in vitro model of myeloid bipotent progenitors. Consistent with the essential role of ERK1/2 during macrophage differentiation and defects of macrophagic differentiation in native ERK1(-/-) progenitors, ERK signaling is strongly activated in Eger/Fms cells upon M-CSF-induced macrophagic differentiation but only to a very small extent during G-CSF-induced granulocytic differentiation. Previous in vivo studies indicated a key role of Fli-1 in myeloid differentiation and demonstrated its weak expression during macrophagic differentiation with a strong expression during granulocytic differentiation. Here, we demonstrated that this effect could be mediated by a differential regulation of protein kinase Cδ (PKCd) on Fli-1 expression in response to M-CSF and G-CSF. With the use of knockdown of PKCd by small interfering RNA, we demonstrated that M-CSF activates PKCd, which in turn, inhibits Fli-1 expression and granulocytic differentiation. Finally, we studied the connection between ERK and PKCd and showed that in the presence of the MEK inhibitor U0126, PKCd expression is decreased, and Fli-1 expression is increased in response to M-CSF. Altogether, we demonstrated that in bipotent myeloid cells, M-CSF promotes macrophagic over granulocytic differentiation by inducing ERK activation but also PKCd expression, which in turn, down-regulates Fli-1 expression and prevents granulocytic differentiation.

  14. Cardiac Relapse of Acute Myeloid Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation

    Science.gov (United States)

    Sánchez-Quintana, Ana; Quijada-Fumero, Alejandro; Laynez-Carnicero, Ana; Breña-Atienza, Joaquín; Poncela-Mireles, Francisco J.; Llanos-Gómez, Juan M.; Cabello-Rodríguez, Ana I.; Ramos-López, María

    2016-01-01

    Secondary or metastatic cardiac tumors are much more common than primary benign or malignant cardiac tumors. Any tumor can cause myocardial or pericardial metastasis, although isolated or combined tumor invasion of the pericardium is more common. Types of neoplasia with the highest rates of cardiac or pericardial involvement are melanoma, lung cancer, and breast and mediastinal carcinomas. Acute myeloid leukemia (AML) is the most common type of acute leukemia in adults. Initial treatment involves chemotherapy followed by consolidation treatment to reduce the risk of relapse. In high-risk patients, the treatment of choice for consolidation is hematopoietic stem cell transplantation (HSCT). Relapse of AML is the most common cause of HSCT failure. Extramedullary relapse is rare. The organs most frequently affected, called “sanctuaries,” are the testes, ovaries, and central nervous system. We present a case with extramedullary relapse in the form of a solid cardiac mass. PMID:27642531

  15. Small-molecule Hedgehog inhibitor attenuates the leukemia-initiation potential of acute myeloid leukemia cells.

    Science.gov (United States)

    Fukushima, Nobuaki; Minami, Yosuke; Kakiuchi, Seiji; Kuwatsuka, Yachiyo; Hayakawa, Fumihiko; Jamieson, Catoriona; Kiyoi, Hitoshi; Naoe, Tomoki

    2016-10-01

    Aberrant activation of the Hedgehog signaling pathway has been implicated in the maintenance of leukemia stem cell populations in several model systems. PF-04449913 (PF-913) is a selective, small-molecule inhibitor of Smoothened, a membrane protein that regulates the Hedgehog pathway. However, details of the proof-of-concept and mechanism of action of PF-913 following administration to patients with acute myeloid leukemia (AML) are unclear. This study examined the role of the Hedgehog signaling pathway in AML cells, and evaluated the in vitro and in vivo effects of the Smoothened inhibitor PF-913. In primary AML cells, activation of the Hedgehog signaling pathway was more pronounced in CD34(+) cells than CD34(-) cells. In vitro treatment with PF-913 induced a decrease in the quiescent cell population accompanied by minimal cell death. In vivo treatment with PF-913 attenuated the leukemia-initiation potential of AML cells in a serial transplantation mouse model, while limiting reduction of tumor burden in a primary xenotransplant system. Comprehensive gene set enrichment analysis revealed that PF-913 modulated self-renewal signatures and cell cycle progression. Furthermore, PF-913 sensitized AML cells to cytosine arabinoside, and abrogated resistance to cytosine arabinoside in AML cells cocultured with HS-5 stromal cells. These findings imply that pharmacologic inhibition of Hedgehog signaling attenuates the leukemia-initiation potential, and also enhanced AML therapy by sensitizing dormant leukemia stem cells to chemotherapy and overcoming resistance in the bone marrow microenvironment. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  16. Human Myeloid-derived Suppressor Cells are Associated With Chronic Immune Suppression After Severe Sepsis/Septic Shock.

    Science.gov (United States)

    Mathias, Brittany; Delmas, Amber L; Ozrazgat-Baslanti, Tezcan; Vanzant, Erin L; Szpila, Benjamin E; Mohr, Alicia M; Moore, Frederick A; Brakenridge, Scott C; Brumback, Babette A; Moldawer, Lyle L; Efron, Philip A

    2017-04-01

    We hypothesized that after sepsis in humans, MDSCs will be persistently increased, functionally immunosuppressive, and associated with adverse clinical outcomes. Cancer and sepsis have surprisingly similar immunologic responses and equally dismal long term consequences. In cancer, increased myeloid-derived suppressor cells (MDSCs) induce detrimental immunosuppression, but little is known about the role of MDSCs after sepsis. Blood was obtained from 74 patients within 12 hours of severe sepsis/septic shock (SS/SS), and at set intervals out to 28 days, and also in 18 healthy controls. MDSCs were phenotyped for cell surface receptor expression and enriched by cell sorting. Functional and genome-wide expression analyses were performed. Multiple logistic regression analysis was conducted to determine if increased MDSC appearance was associated with in-hospital and long-term outcomes. After SS/SS, CD33CD11bHLA-DR MDSCs were dramatically increased out to 28 days (P < 0.05). When co-cultured with MDSCs from SS/SS patients, antigen-driven T-cell proliferation and TH1/TH2 cytokine production were suppressed (P < 0.05). Additionally, septic MDSCs had suppressed HLA gene expression and up-regulated ARG1 expression (P < 0.05). Finally, SS/SS patients with persistent increased percentages of blood MDSCs had increased nosocomial infections, prolonged intensive care unit stays, and poor functional status at discharge (P < 0.05). After SS/SS in humans, circulating MDSCs are persistently increased, functionally immunosuppressive, and associated with adverse outcomes. This novel observation warrants further studies. As observed in cancer immunotherapy, MDSCs could be a novel component in multimodality immunotherapy targeting detrimental inflammation and immunosuppression after SS/SS to improve currently observed dismal long-term outcomes.

  17. A comparison of azacitidine and decitabine activities in acute myeloid leukemia cell lines.

    Directory of Open Access Journals (Sweden)

    Paul W Hollenbach

    Full Text Available BACKGROUND: The cytidine nucleoside analogs azacitidine (AZA and decitabine (DAC are used for the treatment of patients with myelodysplastic syndromes and acute myeloid leukemia (AML. Few non-clinical studies have directly compared the mechanisms of action of these agents in a head-to-head fashion, and the agents are often viewed as mechanistically similar DNA hypomethylating agents. To better understand the similarities and differences in mechanisms of these drugs, we compared their in vitro effects on several end points in human AML cell lines. METHODOLOGY/PRINCIPAL FINDINGS: Both drugs effected DNA methyltransferase 1 depletion, DNA hypomethylation, and DNA damage induction, with DAC showing equivalent activity at concentrations 2- to 10-fold lower than AZA. At concentrations above 1 microM, AZA had a greater effect than DAC on reducing cell viability. Both drugs increased the sub-G1 fraction and apoptosis markers, with AZA decreasing all cell cycle phases and DAC causing an increase in G2-M. Total protein synthesis was reduced only by AZA, and drug-modulated gene expression profiles were largely non-overlapping. CONCLUSIONS/SIGNIFICANCE: These data demonstrate shared mechanisms of action of AZA and DAC on DNA-mediated markers of activity, but distinctly different effects in their actions on cell viability, protein synthesis, cell cycle, and gene expression. The differential effects of AZA may be mediated by RNA incorporation, as the distribution of AZA in nucleic acid of KG-1a cells was 65:35, RNA:DNA.

  18. Exosomes released by granulocytic myeloid-derived suppressor cells attenuate DSS-induced colitis in mice.

    Science.gov (United States)

    Wang, Yungang; Tian, Jie; Tang, Xinyi; Rui, Ke; Tian, Xinyu; Ma, Jie; Ma, Bin; Xu, Huaxi; Lu, Liwei; Wang, Shengjun

    2016-03-29

    Myeloid-derived suppressor cells (MDSC) have been described in inflammatory bowel disease (IBD), but their role in the disease remains controversial. We sought to define the effect of granulocytic MDSC-derived exosomes (G-MDSC exo) in dextran sulphate sodium (DSS)-induced murine colitis. G-MDSC exo-treated mice showed greater resistance to colitis, as reflected by lower disease activity index, decreased inflammatory cell infiltration damage. There was a decrease in the proportion of Th1 cells and an increase in the proportion of regulatory T cells (Tregs) in mesenteric lymph nodes (MLNs) from G-MDSC exo-treated colitis mice. Moreover, lower serum levels of interferon (IFN)-γ and tumor necrosis factor (TNF)-α were detected in G-MDSC exo-treated colitis mice. Interestingly, inhibition of arginase (Arg)-1 activity in G-MDSC exo partially abrogated the spontaneous improvement of colitis. In addition, G-MDSC exo could suppress CD4+ T cell proliferation and IFN-γ secretion in vitro and inhibit the delayed-type hypersensitivity (DTH) response, and these abilities were associated with Arg-1 activity. Moreover, G-MDSC exo promoted the expansion of Tregs in vitro. Taken together, these results suggest that G-MDSC exo attenuate DSS-induced colitis through inhibiting Th1 cells proliferation and promoting Tregs expansion.

  19. Molecular analysis of the apoptotic effects of BPA in acute myeloid leukemia cells

    Directory of Open Access Journals (Sweden)

    Del Pozzo Giovanna

    2009-06-01

    Full Text Available Abstract Background: BPA (bisphenol A or 2,2-bis(4-hydroxy-phenolpropane is present in the manufacture of polycarbonate plastic and epoxy resins, which can be used in impact-resistant safety equipment and baby bottles, as protective coatings inside metal food containers, and as composites and sealants in dentistry. Recently, attention has focused on the estrogen-like and carcinogenic adverse effects of BPA. Thus, it is necessary to investigate the cytotoxicity and apoptosis-inducing activity of this compound. Methods: Cell cycle, apoptosis and differentiation analyses; western blots. Results: BPA is able to induce cell cycle arrest and apoptosis in three different acute myeloid leukemias. Although some granulocytic differentiation concomitantly occurred in NB4 cells upon BPA treatment, the major action was the induction of apoptosis. BPA mediated apoptosis was caspase dependent and occurred by activation of extrinsic and intrinsic cell death pathways modulating both FAS and TRAIL and by inducing BAD phosphorylation in NB4 cells. Finally, also non genomic actions such as the early decrease of both ERK and AKT phosphorylation were induced by BPA thus indicating that a complex intersection of regulations occur for the apoptotic action of BPA. Conclusion: BPA is able to induce apoptosis in leukemia cells via caspase activation and involvement of both intrinsic and extrinsic pathways of apoptosis.

  20. Notch signalling drives bone marrow stromal cell-mediated chemoresistance in acute myeloid leukemia.

    Science.gov (United States)

    Takam Kamga, Paul; Bassi, Giulio; Cassaro, Adriana; Midolo, Martina; Di Trapani, Mariano; Gatti, Alessandro; Carusone, Roberta; Resci, Federica; Perbellini, Omar; Gottardi, Michele; Bonifacio, Massimiliano; Nwabo Kamdje, Armel Hervé; Ambrosetti, Achille; Krampera, Mauro

    2016-04-19

    Both preclinical and clinical investigations suggest that Notch signalling is critical for the development of many cancers and for their response to chemotherapy. We previously showed that Notch inhibition abrogates stromal-induced chemoresistance in lymphoid neoplasms. However, the role of Notch in acute myeloid leukemia (AML) and its contribution to the crosstalk between leukemia cells and bone marrow stromal cells remain controversial. Thus, we evaluated the role of the Notch pathway in the proliferation, survival and chemoresistance of AML cells in co-culture with bone marrow mesenchymal stromal cells expanded from both healthy donors (hBM-MSCs) and AML patients (hBM-MSCs*). As compared to hBM-MSCs, hBM-MSCs* showed higher level of Notch1, Jagged1 as well as the main Notch target gene HES1. Notably, hBM-MSCs* induced expression and activation of Notch signalling in AML cells, supporting AML proliferation and being more efficientin inducing AML chemoresistance than hBM-MSCs*. Pharmacological inhibition of Notch using combinations of Notch receptor-blocking antibodies or gamma-secretase inhibitors (GSIs), in presence of chemotherapeutic agents, significant lowered the supportive effect of hBM-MSCs and hBM-MSCs* towards AML cells, by activating apoptotic cascade and reducing protein level of STAT3, AKT and NF-κB.These results suggest that Notch signalling inhibition, by overcoming the stromal-mediated promotion of chemoresistance,may represent a potential therapeutic targetnot only for lymphoid neoplasms, but also for AML.

  1. Increased peroxisome proliferator-activated receptor-gamma activity reduces imatinib uptake and efficacy in chronic myeloid leukemia mononuclear cells.

    Science.gov (United States)

    Wang, Jueqiong; Lu, Liu; Kok, Chung H; Saunders, Verity A; Goyne, Jarrad M; Dang, Phuong; Leclercq, Tamara M; Hughes, Timothy P; White, Deborah L

    2017-02-02

    Imatinib is actively transported by OCT-1 influx transporter, and low OCT-1 activity in diagnostic chronic myeloid leukemia blood mononuclear cells is significantly associated with poor molecular response to imatinib. Here we report that, in diagnostic chronic myeloid leukemia mononuclear cells and BCR-ABL1+ cell lines, peroxisome proliferator-activated receptor gamma agonists (GW1929, rosiglitazone, pioglitazone) significantly decrease OCT-1 activity; conversely, peroxisome proliferator-activated receptor gamma antagonists (GW9662, T0070907) increase OCT-1 activity. Importantly, these effects can lead to corresponding changes in sensitivity to Bcr-Abl kinase inhibition. Results were confirmed in peroxisome proliferator-activated receptor gamma-transduced K562 cells. Furthermore, we identified a strong negative correlation between OCT-1 activity and peroxisome proliferator-activated receptor gamma transcriptional activity in diagnostic chronic myeloid leukemia patients (n=84; preceptor gamma activation has a negative impact on the intracellular uptake of imatinib and consequent Bcr-Abl kinase inhibition. The inter-patient variability of peroxisome proliferator-activated receptor gamma activation likely accounts for the heterogeneity observed in patient OCT-1 activity at diagnosis. Recently, the peroxisome proliferator-activated receptor gamma agonist pioglitazone was reported to act synergistically with imatinib targeting the residual chronic myeloid leukemia stem cell pool. Our findings suggest that peroxisome proliferator-activated receptor gamma ligands have differential effects on circulating mononuclear cells compared to stem cells. Since the effect of peroxisome proliferator-activated receptor gamma activation on imatinib uptake in mononuclear cells may counteract the clinical benefit of this activation in stem cells, caution should be applied when combining these therapies, especially in patients with high peroxisome proliferator-activated receptor gamma

  2. Growth arrest specific 2 is up-regulated in chronic myeloid leukemia cells and required for their growth.

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    Haixia Zhou

    Full Text Available Although the generation of BCR-ABL is the molecular hallmark of chronic myeloid leukemia (CML, the comprehensive molecular mechanisms of the disease remain unclear yet. Growth arrest specific 2 (GAS2 regulates multiple cellular functions including cell cycle, apoptosis and calpain activities. In the present study, we found GAS2 was up-regulated in CML cells including CD34+ progenitor cells compared to their normal counterparts. We utilized RNAi and the expression of dominant negative form of GAS2 (GAS2DN to target GAS2, which resulted in calpain activity enhancement and growth inhibition of both K562 and MEG-01 cells. Targeting GAS2 also sensitized K562 cells to Imatinib mesylate (IM. GAS2DN suppressed the tumorigenic ability of MEG-01 cells and impaired the tumour growth as well. Moreover, the CD34+ cells from CML patients and healthy donors were transduced with control and GAS2DN lentiviral vectors, and the CD34+ transduced (YFP+ progeny cells (CD34+YFP+ were plated for colony-forming cell (CFC assay. The results showed that GAS2DN inhibited the CFC production of CML cells by 57±3% (n = 3, while affected those of normal hematopoietic cells by 31±1% (n = 2. Next, we found the inhibition of CML cells by GAS2DN was dependent on calpain activity but not the degradation of beta-catenin. Lastly, we generated microarray data to identify the differentially expressed genes upon GAS2DN and validated that the expression of HNRPDL, PTK7 and UCHL5 was suppressed by GAS2DN. These 3 genes were up-regulated in CML cells compared to normal control cells and the growth of K562 cells was inhibited upon HNRPDL silence. Taken together, we have demonstrated that GAS2 is up-regulated in CML cells and the inhibition of GAS2 impairs the growth of CML cells, which indicates GAS2 is a novel regulator of CML cells and a potential therapeutic target of this disease.

  3. Cytoplasmic localization of NPM in myeloid leukemias is dictated by gain-of-function mutations that create a functional nuclear export signal.

    Science.gov (United States)

    Mariano, A R; Colombo, E; Luzi, L; Martinelli, P; Volorio, S; Bernard, L; Meani, N; Bergomas, R; Alcalay, M; Pelicci, P G

    2006-07-20

    Nucleophosmin (NPM) is a nucleus-cytoplasmic shuttling protein that is implicated in centrosome duplication, cell cycle progression and stress response. At the steady state, NPM localizes mainly in the nucleolus, where it forms a complex with different cellular proteins. One-third of acute myeloid leukemias (AML) are characterized by aberrant cytoplasmic localization of NPM, due to mutations within its last coding exon (exon 12) that cause a frameshift and the formation of novel C-termini. We report here our investigations on the molecular basis for the aberrant localization of mutated NPM. Alignment of the C-terminus of the various NPM mutants revealed the obligatory presence of four amino-acid residues that match a CRM1-dependent nuclear export signal (NES). Single alanine-substitutions at these sites provoked nuclear re-localization, while fusion of the mutated C-terminus to a heterologous nuclear protein induced CRM1-dependent cytoplasmic localization. Molecular characterization of one exceptional AML carrying cytoplasmic NPM and germ line exon 12 revealed a somatic mutation in the splicing donor site of exon 9 that caused the formation of a functional NES. It appears, therefore, that AMLs are frequently characterized by gain-of-function mutations of NPM that create functional NES, suggesting that alterations of nuclear export might represent a general mechanism of leukemogenesis and a novel target for therapeutic intervention.

  4. Donor Umbilical Cord Blood Transplant With or Without Ex-vivo Expanded Cord Blood Progenitor Cells in Treating Patients With Acute Myeloid Leukemia, Acute Lymphoblastic Leukemia, Chronic Myelogenous Leukemia, or Myelodysplastic Syndromes

    Science.gov (United States)

    2017-09-14

    Acute Biphenotypic Leukemia; Acute Erythroid Leukemia; Acute Lymphoblastic Leukemia in Remission; Acute Megakaryoblastic Leukemia; Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome; Acute Myeloid Leukemia in Remission; Blasts Under 10 Percent of Bone Marrow Nucleated Cells; Chronic Myelogenous Leukemia, BCR-ABL1 Positive; Mixed Phenotype Acute Leukemia; Myelodysplastic Syndrome; Myelodysplastic Syndrome With Excess Blasts; Pancytopenia; Refractory Anemia; Secondary Acute Myeloid Leukemia

  5. Exogenous cardiolipin localizes to mitochondria and prevents TAZ knockdown-induced apoptosis in myeloid progenitor cells.

    Science.gov (United States)

    Ikon, Nikita; Su, Betty; Hsu, Fong-Fu; Forte, Trudy M; Ryan, Robert O

    2015-08-21

    The concentration and composition of cardiolipin (CL) in mitochondria are altered in age-related heart disease, Barth Syndrome, and other rare genetic disorders, resulting in mitochondrial dysfunction. To explore whether exogenous CL can be delivered to cells, CL was combined with apolipoprotein A-I to generate water-soluble, nanoscale complexes termed nanodisks (ND). Mass spectrometry of HL60 myeloid progenitor cell extracts revealed a 30-fold increase in cellular CL content following incubation with CL-ND. When CL-ND containing a fluorescent CL analogue was employed, confocal microscopy revealed CL localization to mitochondria. The ability of CL-ND to elicit a physiological response was examined in an HL60 cell culture model of Barth Syndrome neutropenia. siRNA knockdown of the phospholipid transacylase, tafazzin (TAZ), induced apoptosis in these cells. When TAZ knockdown cells were incubated with CL-ND, the apoptotic response was attenuated. Thus, CL-ND represent a potential intervention strategy for replenishment of CL in Barth Syndrome, age-related heart disease, and other disorders characterized by depletion of this key mitochondrial phospholipid.

  6. Hypoxia-sensitive epigenetic regulation of an antisense-oriented lncRNA controls WT1 expression in myeloid leukemia cells.

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    Gregory McCarty

    Full Text Available WT1 is a transcription factor expressed in hematopoietic stem cells and in most cases of myeloid leukemia. We investigated the roles of hypoxia and epigenetics in the regulation of WT1 expression in myeloid leukemia cells. WT1 expression correlates with hypomethylation of the CpG island in Intron 1, and pharmacologic demethylation of this CpG island induces WT1 mRNA expression. Hypoxia causes decreases in DNMT expression and activity and increased expression and activity of TET2 and TET3, resulting in demethylation of this CpG island and expression of WT1 mRNA. Demethylation of the CpG island, either from pharmacologic treatment or induction of hypoxia, results in transcription of an antisense-oriented lncRNA, and inhibiting lncRNA expression with shRNA blocks WT1 mRNA expression. These results reveal a novel model of hypoxia-mediated epigenetic gene regulation. In addition, this is the first report that TET2 and TET3, increasingly recognized as important epigenetic regulators of gene expression in stem cells and in cancer cells, can be regulated by hypoxia, providing a solid mechanistic link between hypoxia and epigenetic regulation of gene expression with important implications for the role of hypoxia in stem cell function.

  7. Tumor-induced CD11b(+) Gr-1(+) myeloid-derived suppressor cells exacerbate immune-mediated hepatitis in mice in a CD40-dependent manner.

    Science.gov (United States)

    Kapanadze, Tamar; Medina-Echeverz, José; Gamrekelashvili, Jaba; Weiss, Jonathan M; Wiltrout, Robert H; Kapoor, Veena; Hawk, Nga; Terabe, Masaki; Berzofsky, Jay A; Manns, Michael P; Wang, Ena; Marincola, Francesco M; Korangy, Firouzeh; Greten, Tim F

    2015-04-01

    Immunosuppressive CD11b(+) Gr-1(+) myeloid-derived suppressor cells (MDSCs) accumulate in the livers of tumor-bearing (TB) mice. We studied hepatic MDSCs in two murine models of immune-mediated hepatitis. Unexpectedly, treatment of TB mice with Concanavalin A (Con A) or α-galactosylceramide resulted in increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) serum levels in comparison to tumor-free mice. Adoptive transfer of hepatic MDSCs into naïve mice exacerbated Con A induced liver damage. Hepatic CD11b(+) Gr-1(+) cells revealed a polarized proinflammatory gene signature after Con A treatment. An IFN-γ-dependent upregulation of CD40 on hepatic CD11b(+) Gr-1(+) cells along with an upregulation of CD80, CD86, and CD1d after Con A treatment was observed. Con A treatment resulted in a loss of suppressor function by tumor-induced CD11b(+) Gr-1(+) MDSCs as well as enhanced reactive oxygen species (ROS)-mediated hepatotoxicity. CD40 knockdown in hepatic MDSCs led to increased arginase activity upon Con A treatment and lower ALT/AST serum levels. Finally, blockade of arginase activity in Cd40(-/-) tumor-induced myeloid cells resulted in exacerbation of hepatitis and increased ROS production in vivo. Our findings indicate that in a setting of acute hepatitis, tumor-induced hepatic MDSCs act as proinflammatory immune effector cells capable of killing hepatocytes in a CD40-dependent manner.

  8. HLA-G promotes myeloid-derived suppressor cell accumulation and suppressive activity during human pregnancy through engagement of the receptor ILT4.

    Science.gov (United States)

    Köstlin, Natascha; Ostermeir, Anna-Lena; Spring, Bärbel; Schwarz, Julian; Marmé, Alexander; Walter, Christina B; Poets, Christian F; Gille, Christian

    2017-02-01

    Establishing and maintaining maternal-fetal tolerance is essential for a successful pregnancy; failure of immunological adaptation to pregnancy leads to severe complications such as abortion or preterm delivery. Myeloid-derived suppressor cells (MDSCs) are innate immune cells that suppress T-cell responses, expand during pregnancy and thus may play a role in tolerance induction. Human leucocyte antigen G (HLA-G) is a major histocompatibility complex (MHC) I molecule with immune-modulatory properties, which is expressed during pregnancy. Here, we investigated the impact of HLA-G on MDSCs accumulation and activation in pregnant women. We demonstrate that granulocytic MDSCs (GR-MDSCs) express receptors for HLA-G, namely immunoglobulin-like transcript (ILT) 2 and 4, and that ILT4-expression by GR-MDSCs is regulated during pregnancy. Stimulation with soluble HLA-G (sHLA-G) increased suppressive activity of GR-MDSCs, induced MDSCs from peripheral blood mononuclear cells (PBMCs) and led to phosphorylation of the signal transducer and activator of transcription 3 (STAT3) and induction of indoleamine-2,3-dioxygenase (IDO) in myeloid cells. Effects of sHLA-G on MDSC accumulation were mediated through ILT4. These results suggest an interaction between MDSCs and HLA-G in humans as a potential mechanism for maintaining maternal-fetal tolerance. Modulating MDSC function during pregnancy via HLA-G might provide new opportunities for a therapeutic manipulation of immunological pregnancy complications.

  9. Expression and the role of myeloid-derived suppressor cells in the peripheral blood in patients with chronic hepatitis B

    Institute of Scientific and Technical Information of China (English)

    陆丽蓉

    2014-01-01

    Objective To investigate the correlation between the frequency of myeloid-derived suppressor cells(MDSC)and the frequency of regulatory T cells(Treg)in the peripheral blood in patients with chronic hepatitis B(CHB)and its clinical significance.Methods A total of 45 CHB patients including 23 mild-to-moderate CHB patients,22severe CHB patients,and 15 healhy control cytometry

  10. HPV16-associated tumors control myeloid cell homeostasis in lymphoid organs, generating a suppressor environment for T cells.

    Science.gov (United States)

    Stone, Simone Cardozo; Rossetti, Renata Ariza Marques; Bolpetti, Aline; Boccardo, Enrique; Souza, Patricia Savio de Araujo; Lepique, Ana Paula

    2014-10-01

    Tumors are complex structures containing different types of cells and molecules. The importance of the tumor microenvironment in tumor progression, growth, and maintenance is well-established. However, tumor effects are not restricted to the tumor microenvironment. Molecules secreted by, as well as cells that migrate from tumors, may circulate and reach other tissues. This may cause a series of systemic effects, including modulation of immune responses, and in some cases, leukocytosis and metastasis promotion. Leukocytosis has been described as a poor prognostic factor in patients with cervical cancer. The main etiological factor for cervical cancer development is persistent infection with high oncogenic risk HPV. Our laboratory has been exploring the effects of high oncogenic risk, HPV-associated tumors on lymphoid organs of the host. In the present study, we observed an increase in myeloid cell proliferation and alteration in cell signaling in APCs in the spleen of tumor-bearing mice. In parallel, we characterized the cytokines secreted in the inflammatory and tumor cell compartments in the tumor microenvironment and in the spleen of tumor-bearing mice. We show evidence of constitutive activation of the IL-6/STAT3 signaling pathway in the tumor, including TAMs, and in APCs in the spleen. We also observed that IL-10 is a central molecule in the tolerance toward tumor antigens through control of NF-κB activation, costimulatory molecule expression, and T cell proliferation. These systemic effects over myeloid cells are robust and likely an important problem to be addressed when considering strategies to improve anti-tumor T cell responses.

  11. Phenotypic and functional plasticity of cells of innate immunity: macrophages, mast cells and neutrophils

    DEFF Research Database (Denmark)

    Galli, Stephen J; Borregaard, Niels; Wynn, Thomas A

    2011-01-01

    Hematopoietic cells, including lymphoid and myeloid cells, can develop into phenotypically distinct 'subpopulations' with different functions. However, evidence indicates that some of these subpopulations can manifest substantial plasticity (that is, undergo changes in their phenotype and functio...... a common mechanism for modulating innate or adaptive immunity.......). Here we focus on the occurrence of phenotypically distinct subpopulations in three lineages of myeloid cells with important roles in innate and acquired immunity: macrophages, mast cells and neutrophils. Cytokine signals, epigenetic modifications and other microenvironmental factors can substantially...... and, in some cases, rapidly and reversibly alter the phenotype of these cells and influence their function. This suggests that regulation of the phenotype and function of differentiated hematopoietic cells by microenvironmental factors, including those generated during immune responses, represents...

  12. alpha1-Antitrypsin therapy downregulates toll-like receptor-induced IL-1beta responses in monocytes and myeloid dendritic cells and may improve islet function in recently diagnosed patients with type 1 diabetes

    NARCIS (Netherlands)

    Gottlieb, P.A.; Alkanani, A.K.; Michels, A.W.; Lewis, E.C.; Shapiro, L.; Dinarello, C.A.; Zipris, D.

    2014-01-01

    CONTEXT: Recent studies have implicated proinflammatory responses in the mechanism of type 1 diabetes (T1D). OBJECTIVE: Our objective was to evaluate the safety and effects of therapy with the anti-inflammatory serum protein alpha1-antitrypsin (AAT) on islet function and innate immunity in recent-on

  13. [Dendritic cells (DC) induced from acute myeloid leukemia (AML) cells with cytokine cocktails].

    Science.gov (United States)

    Yan, Kuang-hua; You, Sheng-guo; Bian, Shou-geng; Ma, Guan-jie; Ge, Wei; Ma, Shuang; Liu, Shi-he; Zhao, Chun-hua

    2003-07-01

    To explore the feasibility of DC being in vitro induced from AML cells with cytokine cocktails and their biological properties. AML cells were cultured in either presence or absence of cytokine cocktails. DC were studied for morphology, and cytochemical and immunofluorescent staining. Functions of DC were examined by MLC, FITC-conjugated dextran uptake test, and LDH release assay. RT-PCR and FISH were used to analyze the specific fusion genes of culture-derived DC. Classical DC morphological changes occurred in all 15 cultured AML cells. DC-associated surface molecules such as CD(1a), CD(80), CD(86), CD(106), CD(83) and HLA-DR were upregulated (P AML cells uncultured or cultured in the absence of cytokines (P CTL assay was performed in 5 of the 15 samples. At effector/target ratio of 20:1, auto-T lymphocytes primed with the culture-derived DC exhibited no more killing activity to auto-AML cells than those stimulated by IL-2 or uncultured AML cells. Culture-derived DC presenced the native AML-specific aberrant karyotype and related fusion gene. Cytokine cocktails could in vitro induce AML cells into DC with classical morphology, immunophenotype and function. DC maturity induced by different cytokine cocktails could be variable. Culture-derived DC were originated from the native AML cells. AML cells could make the auto-T lymphocyte anergy.

  14. T-cell/myeloid mixed-phenotype acute leukemia with monocytic differentiation and isolated 17p deletion

    Directory of Open Access Journals (Sweden)

    Germison Silva Lopes

    2014-07-01

    Full Text Available Mixed phenotype acute leukemia is a rare subtype of leukemia that probably arises from a hematopoietic pluripotent stem cell. The co-expression of two of myeloid, B- or T-lymphoid antigens is the hallmark of this disease. Herein, the case of a 28-year-old female patient is reported who presented with hemoglobin of 5.8 g/dL, white blood cell count of 138 × 109/L and platelet count of 12 × 109/L. The differential count of peripheral blood revealed 96% of blasts. Moreover, the patient presented with lymphadenopathy, splenomegaly and bone marrow infiltration by monocytoid blasts characterized as 7% positivity by Sudan Black cytochemical staining. Immunophenotyping revealed the involvement of blasts of both T- and monocytic lineages. The cytogenetic analysis showed an isolated 17p deletion. Thus, the diagnosis of T-cell/myeloid mixed phenotype acute leukemia was made with two particular rare features, that is, the monocytic differentiation and the 17p deletion as unique cytogenetic abnormalities. The possibility of concomitant expressions of T-cell and monocytic differentiation antigens in the same blast population is hard to explain using the classical model of hematopoiesis. However, recent studies have suggested that myeloid potential persists even when the lineage branches segregate toward B- and T-cells. The role of an isolated 17p deletion in the pathogenesis of this condition is unclear. At present, the patient is in complete remission after an allogeneic stem cell transplantation procedure.

  15. Allogeneic hematopoietic cell transplant for acute myeloid leukemia: Current state in 2013 and future directions.

    Science.gov (United States)

    Kanate, Abraham S; Pasquini, Marcelo C; Hari, Parameswaran N; Hamadani, Mehdi

    2014-04-26

    Acute myeloid leukemia (AML) represents a heterogeneous group of high-grade myeloid neoplasms of the elderly with variable outcomes. Though remission-induction is an important first step in the management of AML, additional treatment strategies are essential to ensure long-term disease-free survival. Recent pivotal advances in understanding the genetics and molecular biology of AML have allowed for a risk-adapted approach in its management based on relapse-risk. Allogeneic hematopoietic cell transplantation (allo-HCT) represents an effective therapeutic strategy in AML providing the possibility of cure with potent graft-versus-leukemia reactions, with a demonstrable survival advantage in younger patients with intermediate- or poor-risk cytogenetics. Herein we review the published data regarding the role of allo-HCT in adults with AML. We searched MEDLINE/PubMed and EMBASE/Ovid. In addition, we searched reference lists of relevant articles, conference proceedings and ongoing trial databases. We discuss the role of allo-HCT in AML patients stratified by cytogenetic- and molecular-risk in first complete remission, as well as allo-HCT as an option in relapsed/refractory AML. Besides the conventional sibling and unrelated donor allografts, we review the available data and recent advances for alternative donor sources such as haploidentical grafts and umbilical cord blood. We also discuss conditioning regimens, including reduced intensity conditioning which has broadened the applicability of allo-HCT. Finally we explore recent advances and future possibilities and directions of allo-HCT in AML. Practical therapeutic recommendations have been made where possible based on available data and expert opinion.

  16. Cooperative antiproliferative and differentiation-enhancing activity of medicinal plant extracts in acute myeloid leukemia cells.

    Science.gov (United States)

    Zhamanbayeva, Gulzhan T; Aralbayeva, Araylim N; Murzakhmetova, Maira K; Tuleukhanov, Sultan T; Danilenko, Michael

    2016-08-01

    Acute myeloid leukemia (AML) is an aggressive hematopoietic malignancy with poor prognosis and limited treatment options. Sea buckthorn (Hippophae rhamnoides) berries, dog rose (Rosa canina) rosehips, and garden sage (Salvia officinalis) and oregano (Origanum vulgare) aerial parts are widely used in traditional medicine and exhibit antitumor effects in preclinical models. However, these plants remain scarcely tested for antileukemic activity. Here, we show that their water-ethanol leaf extracts reduced the growth and viability of AML cells and, at non-cytotoxic doses, potentiated cell differentiation induced by a low concentration of 1α,25-dihydroxyvitamin D3, the hormonal form of vitamin D, in a cell type-dependent manner. The latter effect was accompanied by upregulation of the vitamin D receptor protein components and its transcriptional activity. Furthermore, at minimally effective doses the extracts cooperated with one another to produce marked cytostatic effects associated with a partial S-phase arrest and a modest induction of apoptosis. In contrast, these combinations only slightly affected the growth and viability of proliferating normal human peripheral blood mononuclear cells. In addition, the extracts strongly inhibited microsomal lipid peroxidation and protected normal erythrocytes against hypoosmotic shock. Our results suggest that further exploration of the enhanced antileukemic effects of the combinations tested here may lead to the development of alternative therapeutic and preventive approaches against AML. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Clonal architecture of secondary acute myeloid leukemia defined by single-cell sequencing.

    Directory of Open Access Journals (Sweden)

    Andrew E O Hughes

    2014-07-01

    Full Text Available Next-generation sequencing has been used to infer the clonality of heterogeneous tumor samples. These analyses yield specific predictions-the population frequency of individual clones, their genetic composition, and their evolutionary relationships-which we set out to test by sequencing individual cells from three subjects diagnosed with secondary acute myeloid leukemia, each of whom had been previously characterized by whole genome sequencing of unfractionated tumor samples. Single-cell mutation profiling strongly supported the clonal architecture implied by the analysis of bulk material. In addition, it resolved the clonal assignment of single nucleotide variants that had been initially ambiguous and identified areas of previously unappreciated complexity. Accordingly, we find that many of the key assumptions underlying the analysis of tumor clonality by deep sequencing of unfractionated material are valid. Furthermore, we illustrate a single-cell sequencing strategy for interrogating the clonal relationships among known variants that is cost-effective, scalable, and adaptable to the analysis of both hematopoietic and solid tumors, or any heterogeneous population of cells.

  18. Nlrp3-inflammasome activation in non-myeloid-derived cells aggravates diabetic nephropathy.

    Science.gov (United States)

    Shahzad, Khurrum; Bock, Fabian; Dong, Wei; Wang, Hongjie; Kopf, Stefan; Kohli, Shrey; Al-Dabet, Moh'd Mohanad; Ranjan, Satish; Wolter, Juliane; Wacker, Christian; Biemann, Ronald; Stoyanov, Stoyan; Reymann, Klaus; Söderkvist, Peter; Groß, Olaf; Schwenger, Vedat; Pahernik, Sascha; Nawroth, Peter P; Gröne, Herman-Josef; Madhusudhan, Thati; Isermann, Berend

    2015-01-01

    Diabetic nephropathy is a growing health concern with characteristic sterile inflammation. As the underlying mechanisms of this inflammation remain poorly defined, specific therapies targeting sterile inflammation in diabetic nephropathy are lacking. Intriguingly, an association of diabetic nephropathy with inflammasome activation has recently been shown, but the pathophysiological relevance of this finding remains unknown. Within glomeruli, inflammasome activation was detected in endothelial cells and podocytes in diabetic humans and mice and in glucose-stressed glomerular endothelial cells and podocytes in vitro. Abolishing Nlrp3 or caspase-1 expression in bone marrow-derived cells fails to protect mice against diabetic nephropathy. Conversely, Nlrp3-deficient mice are protected against diabetic nephropathy despite transplantation of wild-type bone marrow. Pharmacological IL-1R antagonism prevented or even reversed diabetic nephropathy in mice. Mitochondrial reactive oxygen species (ROS) activate the Nlrp3 inflammasome in glucose or advanced glycation end product stressed podocytes. Inhibition of mitochondrial ROS prevents glomerular inflammasome activation and nephropathy in diabetic mice. Thus, mitochondrial ROS and Nlrp3-inflammasome activation in non-myeloid-derived cells aggravate diabetic nephropathy. Targeting the inflammasome may be a potential therapeutic approach to diabetic nephropathy.

  19. Induction of apoptosis in human myeloid leukemia cells by remote exposure of resistive barrier cold plasma.

    Science.gov (United States)

    Thiyagarajan, Magesh; Anderson, Heather; Gonzales, Xavier F

    2014-03-01

    Cold atmospheric plasma (CAP), an ambient temperature ionized gas, is gaining extensive interest as a promising addition to anti-tumor therapy primarily due to the ability to generate and control delivery of electrons, ions, excited molecules, UV photons, and reactive species such as reactive oxygen species (ROS) and reactive nitrogen species (RNS) to a specific site. The heterogeneous composition of CAP offers the opportunity to mediate several signaling pathways that regulate tumor cells. Consequently, the array of CAP generated products has limited the identification of the mechanisms of action on tumor cells. The aim of this work is to assess the cell death response of human myeloid leukemia cells by remote exposure to CAP generated RNS by utilizing a novel resistive barrier discharge system that primarily produces RNS. The effect of variable treatments of CAP generated RNS was tested in THP-1 cell (human monocytic leukemia cell line), a model for hematological malignancy. The number of viable cells was evaluated with erythrosine-B staining, while apoptosis and necrosis was assessed by endonuclease cleavage observed by agarose gel electrophoresis and detection of cells with the exclusionary dye propidium iodide and fluorescently labeled annexin-V by flow cytometry and fluorescent microscopy. Our observations indicate that treatment dosage levels of 45 s of exposure to CAP emitted RNS-induced apoptotic cell death and for higher dosage conditions of ≥50 s of exposure to CAP induced necrosis. Overall the results suggest that CAP emitted RNS play a significant role in the anti-tumor potential of CAP.

  20. Influence of different fluid resuscitation techniques on the number of myeloid-derived suppressor cells in rats.

    Science.gov (United States)

    Wang, Z J; Wang, H X; Li, L; Wang, L; Dou, H H

    2016-04-28

    We investigated the influence of different fluid resuscitation techniques on the number of myeloid-derived suppressor cells (MDSCs) in rats. Seventy-two healthy Sprague-Dawley rats were randomly divided into groups that received sham operation (Sham group), hypertonic saline (HRS group), lactated ringer's solution (LRS group), or crystalloid solution (LCRS group). Six rats from each group were sacrificed by cervical dislocation at 12, 24, and 48 h after resuscitation. The spleens were harvested under sterile conditions and spleen cell suspension was prepared. The number of MDSCs was detected using flow cytometry. The number of MDSCs in the Sham group did not differ significantly among the different time points. Compared with the Sham group, the number of MDSCs after the use of the different fluid resuscitation techniques increased to varying extents and the differences among the groups were significant. The number of MDSCs in the HRS group was much lower than that of the LRS and LCRS groups at both 24 and 48 h (P number of MDSCs in the HRS group was significantly lower than that of the LRS group (P < 0.05). The differences between the HRS and LCRS groups were not statistically significant. Shortly after hemorrhagic shock resuscitation, the immune function of rats was suppressed to a varying extent and was gradually restored over time. Resuscitation with HRS alleviated the immunosuppression at the early stage after shock.

  1. The new low-toxic histone deacetylase inhibitor S-(2) induces apoptosis in various acute myeloid leukaemia cells.

    Science.gov (United States)

    Cellai, C; Balliu, M; Laurenzana, A; Guandalini, L; Matucci, R; Miniati, D; Torre, E; Nebbioso, A; Carafa, V; Altucci, L; Romanelli, M N; Paoletti, F

    2012-08-01

    Histone deacetylase inhibitors (HDACi) induce tumour cell cycle arrest and/or apoptosis, and some of them are currently used in cancer therapy. Recently, we described a series of powerful HDACi characterized by a 1,4-benzodiazepine (BDZ) ring hybridized with a linear alkyl chain bearing a hydroxamate function as Zn(++)--chelating group. Here, we explored the anti-leukaemic properties of three novel hybrids, namely the chiral compounds (S)-2 and (R)-2, and their non-chiral analogue 4, which were first comparatively tested in promyelocytic NB4 cells. (S)-2 and partially 4--but not (R)-2--caused G0/G1 cell-cycle arrest by up-regulating cyclin G2 and p21 expression and down-regulating cyclin D2 expression, and also apoptosis as assessed by cell morphology and cytofluorimetric assay, histone H2AX phosphorylation and PARP cleavage. Notably, these events were partly prevented by an anti-oxidant. Moreover, novel HDACi prompted p53 and α-tubulin acetylation and, consistently, inhibited HDAC1 and 6 activity. The rank order of potency was (S)-2 > 4 > (R)-2, reflecting that of other biological assays and addressing (S)-2 as the most effective compound capable of triggering apoptosis in various acute myeloid leukaemia (AML) cell lines and blasts from patients with different AML subtypes. Importantly, (S)-2 was safe in mice (up to 150 mg/kg/week) as determined by liver, spleen, kidney and bone marrow histopathology; and displayed negligible affinity for peripheral/central BDZ-receptors. Overall, the BDZ-hydroxamate (S)-2 showed to be a low-toxic HDACi with powerful anti-proliferative and pro-apototic activities towards different cultured and primary AML cells, and therefore of clinical interest to support conventional anti-leukaemic therapy.

  2. Enhanced generation of myeloid lineages in hematopoietic differentiation from embryonic stem cells by silencing transcriptional repressor Twist-2.

    Science.gov (United States)

    Sharabi, Andrew B; Lee, Sung-Hyung; Goodell, Margaret A; Huang, Xue F; Chen, Si-Yi

    2009-12-01

    The self-renewal and multilineage differentiation of embryonic stem cells (ESC) is largely governed by transcription factors or repressors. Extensive efforts have focused on elucidating critical factors that control the differentiation of specific cell lineages, for instance, myeloid lineages in hematopoietic development. In this study, we found that Twist-2, a basic helix-loop-helix (bHLH) transcription factor, plays a critical role in inhibiting the differentiation of ESC. Murine ES cells, in which Twist-2 expression is silenced by lentivirally delivered shRNA, exhibit an enhanced formation of primary embryoid bodies (EB) and enhanced differentiation into mesodermally derived hematopoietic colonies. Furthermore, Twist-2 silenced (LV-siTwist-2) ESC display significantly increased generation of myeloid lineages (Gr-1(+) and F4/80(+) cells) during in vitro hematopoietic differentiation. Treatment with the Toll-like receptor (TLR) 4 ligand synergistically stimulates the generation of primary EB formation as well as of hematopoietic progenitors differentiated from LV-siTwist-2 ES cells. Thus, this study reveals the critical role of the transcriptional repressor Twist-2 in regulating the development of myeloid lineage in hematopoietic differentiation from ESC. This study also suggests a potential strategy for directional differentiation of ESC by inhibiting a transcriptional repressor.

  3. Impact of postremission consolidation chemotherapy on outcome after reduced-intensity conditioning allogeneic stem cell transplantation for patients with acute myeloid leukemia in first complete remission

    DEFF Research Database (Denmark)

    Yeshurun, Moshe; Labopin, Myriam; Blaise, Didier;

    2014-01-01

    The objective of the current study was to investigate the role of postremission consolidation chemotherapy before reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (alloSCT) for patients with acute myeloid leukemia (AML) in first complete remission (CR1).......The objective of the current study was to investigate the role of postremission consolidation chemotherapy before reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (alloSCT) for patients with acute myeloid leukemia (AML) in first complete remission (CR1)....

  4. SAMHD1 enhances nucleoside-analogue efficacy against HIV-1 in myeloid cells

    Science.gov (United States)

    Ordonez, Paula; Kunzelmann, Simone; Groom, Harriet C. T.; Yap, Melvyn W.; Weising, Simon; Meier, Chris; Bishop, Kate N.; Taylor, Ian A.; Stoye, Jonathan P.

    2017-01-01

    SAMHD1 is an intracellular enzyme that specifically degrades deoxynucleoside triphosphates into component nucleoside and inorganic triphosphate. In myeloid-derived dendritic cells and macrophages as well as resting T-cells, SAMHD1 blocks HIV-1 infection through this dNTP triphosphohydrolase activity by reducing the cellular dNTP pool to a level that cannot support productive reverse transcription. We now show that, in addition to this direct effect on virus replication, manipulating cellular SAMHD1 activity can significantly enhance or decrease the anti-HIV-1 efficacy of nucleotide analogue reverse transcription inhibitors presumably as a result of modulating dNTP pools that compete for recruitment by viral polymerases. Further, a variety of other nucleotide-based analogues, not normally considered antiretrovirals, such as the anti-herpes drugs Aciclovir and Ganciclovir and the anti-cancer drug Clofarabine are now revealed as potent anti-HIV-1 agents, under conditions of low dNTPs. This in turn suggests novel uses for nucleotide analogues to inhibit HIV-1 in differentiated cells low in dNTPs. PMID:28220857

  5. Reduced-intensity conditioning allogeneic hematopoietic-cell transplantation for older patients with acute myeloid leukemia.

    Science.gov (United States)

    Goyal, Gaurav; Gundabolu, Krishna; Vallabhajosyula, Saraschandra; Silberstein, Peter T; Bhatt, Vijaya Raj

    2016-06-01

    Elderly patients (>60 years) with acute myeloid leukemia have a poor prognosis with a chemotherapy-alone approach. Allogeneic hematopoietic-cell transplantation (HCT) can improve overall survival (OS). However, myeloablative regimens can have unacceptably high transplant-related mortality (TRM) in an unselected group of older patients. Reduced-intensity conditioning (RIC) or nonmyeloablative (NMA) conditioning regimens preserve the graft-versus-leukemia effects but reduce TRM. NMA regimens result in minimal cytopenia and may not require stem cell support for restoring hematopoiesis. RIC regimens, intermediate in intensity between NMA and myeloablative regimens, can cause prolonged myelosuppresion and usually require stem cell support. A few retrospective and prospective studies suggest a possibility of lower risk of relapse with myeloablative HCT in fit older patients with lower HCT comorbidity index; however, RIC and NMA HCTs have an important role in less-fit patients and those with significant comorbidities because of lower TRM. Whether early tapering of immunosuppression, monitoring of minimal residual disease, and post-transplant maintenance therapy can improve the outcomes of RIC and NMA HCT in elderly patients will require prospective trials.

  6. Arginine deprivation using pegylated arginine deiminase has activity against primary acute myeloid leukemia cells in vivo.

    Science.gov (United States)

    Miraki-Moud, Farideh; Ghazaly, Essam; Ariza-McNaughton, Linda; Hodby, Katharine A; Clear, Andrew; Anjos-Afonso, Fernando; Liapis, Konstantinos; Grantham, Marianne; Sohrabi, Fareeda; Cavenagh, Jamie; Bomalaski, John S; Gribben, John G; Szlosarek, Peter W; Bonnet, Dominique; Taussig, David C

    2015-06-25

    The strategy of enzymatic degradation of amino acids to deprive malignant cells of important nutrients is an established component of induction therapy of acute lymphoblastic leukemia. Here we show that acute myeloid leukemia (AML) cells from most patients with AML are deficient in a critical enzyme required for arginine synthesis, argininosuccinate synthetase-1 (ASS1). Thus, these ASS1-deficient AML cells are dependent on importing extracellular arginine. We therefore investigated the effect of plasma arginine deprivation using pegylated arginine deiminase (ADI-PEG 20) against primary AMLs in a xenograft model and in vitro. ADI-PEG 20 alone induced responses in 19 of 38 AMLs in vitro and 3 of 6 AMLs in vivo, leading to caspase activation in sensitive AMLs. ADI-PEG 20-resistant AMLs showed higher relative expression of ASS1 than sensitive AMLs. This suggests that the resistant AMLs survive by producing arginine through this metabolic pathway and ASS1 expression could be used as a biomarker for response. Sensitive AMLs showed more avid uptake of arginine from the extracellular environment consistent with their auxotrophy for arginine. The combination of ADI-PEG 20 and cytarabine chemotherapy was more effective than either treatment alone resulting in responses in 6 of 6 AMLs tested in vivo. Our data show that arginine deprivation is a reasonable strategy in AML that paves the way for clinical trials.

  7. Expression analyses identify MLL as a prominent target of 11q23 amplification and support an etiologic role for MLL gain of function in myeloid malignancies.

    Science.gov (United States)

    Poppe, Bruce; Vandesompele, Jo; Schoch, Claudia; Lindvall, Charlotta; Mrozek, Krzysztof; Bloomfield, Clara D; Beverloo, H Berna; Michaux, Lucienne; Dastugue, Nicole; Herens, Christian; Yigit, Nurten; De Paepe, Anne; Hagemeijer, Anne; Speleman, Frank

    2004-01-01

    MLL amplification was recently recognized as a recurrent aberration in acute myeloid leukemia (AML) and myelodys-plastic syndrome (MDS), associated with adverse prognosis and karyotype complexity. Here we present detailed results of fluorescence in situ hybridization (FISH) and expression analyses of MLL and 5 selected 11q candidate oncogenes (CBL, DDX6, ETS1, FLI1, and PLZF) in 31 patient samples and one cell line with 11q23 gain. FISH analyses revealed that the 11q23 amplicon invariably encompassed MLL, DDX6, ETS1, and FLI1, whereas expression analyses identified MLL and DDX6 as the most differentially expressed genes among samples with and without 11q23 copy gain or amplification. In MLL-amplified samples, a significant transcriptional up-regulation of MEIS1, PROML1, ADAM10, NKG2D, and ITPA was noted. Further analyses, designed to elucidate a possible role of the 11q overexpressed genes (MLL, DDX6, FLI1, and ETS1) in unselected MDS and AML samples, revealed a significant upregulation of MLL in MDS. Our findings confirm the MLL gene as a prominent target of 11q23 amplification and provide further evidence for an etiologic role for MLL gain of function in myeloid malignancies. In addition, our results indicate that the transcriptional program associated with MLL rearrangements and MLL overexpression displays significant similarities.

  8. Antigen-specific inhibition of CD8+ T cell response by immature myeloid cells in cancer is mediated by reactive oxygen species.

    Science.gov (United States)

    Kusmartsev, Sergei; Nefedova, Yulia; Yoder, Daniel; Gabrilovich, Dmitry I

    2004-01-15

    Tumor growth is associated with the accumulation of immature myeloid cells (ImC), which in mice are characterized by the expression of Gr-1 and CD11b markers. These cells suppress Ag-specific CD8+ T cells via direct cell-cell contact. However, the mechanism of immunosuppressive activity of tumor-derived ImC remains unclear. In this study we analyzed the function of ImC isolated from tumor-free control and tumor-bearing mice. Only ImC isolated from tumor-bearing mice, not those from their control counterparts, were able to inhibit the Ag-specific response of CD8+ T cells. ImC obtained from tumor-bearing mice had significantly higher levels of reactive oxygen species (ROS) than ImC isolated from tumor-free animals. Accumulation of H2O2, but not superoxide or NO, was a major contributor to this increased pool of ROS. It appears that arginase activity played an important role in H2O2 accumulation in these cells. Inhibition of ROS in ImC completely abrogated the inhibitory effect of these cells on T cells, indicating that ImC generated in tumor-bearing hosts suppress the CD8+ T cell response via production of ROS. Interaction of ImC with Ag-specific T cells in the presence of specific Ags resulted in a significant increase in ROS production compared with control Ags. That increase was independent of IFN-gamma production by T cells, but was mediated by integrins CD11b, CD18, and CD29. Blocking of these integrins with specific Abs abrogated ROS production and ImC-mediated suppression of CD8+ T cell responses. This study demonstrates a new mechanism of Ag-specific T cell inhibition mediated by ROS produced by ImCs in cancer.

  9. Genes of cell-cell interactions, chemotherapy detoxification and apoptosis are induced during chemotherapy of acute myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Stordrange Laila

    2009-03-01

    Full Text Available Abstract Background The molecular changes in vivo in acute myeloid leukemia cells early after start of conventional genotoxic chemotherapy are incompletely understood, and it is not known if early molecular modulations reflect clinical response. Methods The gene expression was examined by whole genome 44 k oligo microarrays and 12 k cDNA microarrays in peripheral blood leukocytes collected from seven leukemia patients before treatment, 2–4 h and 18–24 h after start of chemotherapy and validated by real-time quantitative PCR. Statistically significantly upregulated genes were classified using gene ontology (GO terms. Parallel samples were examined by flow cytometry for apoptosis by annexin V-binding and the expression of selected proteins were confirmed by immunoblotting. Results Significant differential modulation of 151 genes were found at 4 h after start of induction therapy with cytarabine and anthracycline, including significant overexpression of 31 genes associated with p53 regulation. Within 4 h of chemotherapy the BCL2/BAX and BCL2/PUMA ratio were attenuated in proapoptotic direction. FLT3 mutations indicated that non-responders (5/7 patients, 8 versus 49 months survival are characterized by a unique gene response profile before and at 4 h. At 18–24 h after chemotherapy, the gene expression of p53 target genes was attenuated, while genes involved in chemoresistance, cytarabine detoxification, chemokine networks and T cell receptor were prominent. No signs of apoptosis were observed in the collected cells, suggesting the treated patients as a physiological source of pre-apoptotic cells. Conclusion Pre-apoptotic gene expression can be monitored within hours after start of chemotherapy in patients with acute myeloid leukemia, and may be useful in future determination of therapy responders. The low number of patients and the heterogeneity of acute myeloid leukemia limited the identification of gene expression predictive of therapy

  10. Triggering receptor expressed on myeloid cells-1 and 2 in bronchoalveolar lavage fluid in pulmonary sarcoidosis.

    Science.gov (United States)

    Suchankova, Magda; Bucova, Maria; Tibenska, Elena; Tedlova, Eva; Demian, Juraj; Majer, Ivan; Novosadova, Helena; Tedla, Miroslav; Paulovicova, Ema; Kantarova, Daniela

    2013-04-01

    Pulmonary sarcoidosis (PS) is characterized by the formation of granulomas in the lungs and has been associated with infection by microorganisms. Triggering receptor expressed on the surface of myeloid cells (TREM)-1 is overexpressed in response to infection while TREM-2 is involved in granuloma formation. We hypothesized that these receptors are overexpressed in PS and might be useful for diagnostic testing. Cell surface TREM-1 and TREM-2 expression in cells obtained at bronchoalveolar lavage (BAL) was measured in individuals with sarcoidosis (n = 26) and compared with that seen in individuals with other interstitial lung diseases (ILD) (n = 27). TREM-1 and TREM-2 expression was significantly increased in sarcoidosis compared with other ILD: total number of TREM-1, P = 0.0039 (23.81 vs 13.50 cells/μl), TREM-2, P < 0.0001 (32.81 vs 7.76 cells/μl); percentage of TREM-1: P = 0.0002 (41.30% vs 15.70%), TREM-2: P < 0.0001 (34% vs 9.60%); and mean fluorescence of TREM-1: P = 0.0005 (5.43 vs 1.96), TREM-2: P = 0.0011 (6.85 vs 2.77). Increase in both of these receptors seems to be typical for PS. In discriminating sarcoidosis from other ILD, the specificity (96%) and sensitivity (72%) of the combination of TREM-1 and TREM-2 was high. Increased TREM-1 and TREM-2 cell surface expression is observed in sarcoidosis. Evaluation of BAL cell expression of both of these receptors may serve as a diagnostic marker for sarcoidosis. © 2013 The Authors. Respirology © 2013 Asian Pacific Society of Respirology.

  11. Cyanobacteria from terrestrial and marine sources contain apoptogens able to overcome chemoresistance in acute myeloid leukemia cells.

    Science.gov (United States)

    Liu, Liwei; Herfindal, Lars; Jokela, Jouni; Shishido, Tania Keiko; Wahlsten, Matti; Døskeland, Stein Ove; Sivonen, Kaarina

    2014-04-03

    In this study, we investigated forty cyanobacterial isolates from biofilms, gastropods, brackish water and symbiotic lichen habitats. Their aqueous and organic extracts were used to screen for apoptosis-inducing activity against acute myeloid leukemia cells. A total of 28 extracts showed cytotoxicity against rat acute myeloid leukemia (IPC-81) cells. The design of the screen made it possible to eliminate known toxins, such as microcystins and nodularin, or known metabolites with anti-leukemic activity, such as adenosine and its analogs. A cytotoxicity test on human embryonic kidney (HEK293T) fibroblasts indicated that 21 of the 28 extracts containing anti-acute myeloid leukemia (AML) activity showed selectivity in favor of leukemia cells. Extracts L26-O and L30-O were able to partly overcome the chemotherapy resistance induced by the oncogenic protein Bcl-2, whereas extract L1-O overcame protection from the deletion of the tumor suppressor protein p53. In conclusion, cyanobacteria are a prolific resource for anti-leukemia compounds that have potential for pharmaceutical applications. Based on the variety of cellular responses, we also conclude that the different anti-leukemic compounds in the cyanobacterial extracts target different elements of the death machinery of mammalian cells.

  12. Cyanobacteria from Terrestrial and Marine Sources Contain Apoptogens Able to Overcome Chemoresistance in Acute Myeloid Leukemia Cells

    Science.gov (United States)

    Liu, Liwei; Herfindal, Lars; Jokela, Jouni; Shishido, Tania Keiko; Wahlsten, Matti; Døskeland, Stein Ove; Sivonen, Kaarina

    2014-01-01

    In this study, we investigated forty cyanobacterial isolates from biofilms, gastropods, brackish water and symbiotic lichen habitats. Their aqueous and organic extracts were used to screen for apoptosis-inducing activity against acute myeloid leukemia cells. A total of 28 extracts showed cytotoxicity against rat acute myeloid leukemia (IPC-81) cells. The design of the screen made it possible to eliminate known toxins, such as microcystins and nodularin, or known metabolites with anti-leukemic activity, such as adenosine and its analogs. A cytotoxicity test on human embryonic kidney (HEK293T) fibroblasts indicated that 21 of the 28 extracts containing anti-acute myeloid leukemia (AML) activity showed selectivity in favor of leukemia cells. Extracts L26-O and L30-O were able to partly overcome the chemotherapy resistance induced by the oncogenic protein Bcl-2, whereas extract L1-O overcame protection from the deletion of the tumor suppressor protein p53. In conclusion, cyanobacteria are a prolific resource for anti-leukemia compounds that have potential for pharmaceutical applications. Based on the variety of cellular responses, we also conclude that the different anti-leukemic compounds in the cyanobacterial extracts target different elements of the death machinery of mammalian cells. PMID:24705501

  13. Cyanobacteria from Terrestrial and Marine Sources Contain Apoptogens Able to Overcome Chemoresistance in Acute Myeloid Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Liwei Liu

    2014-04-01

    Full Text Available In this study, we investigated forty cyanobacterial isolates from biofilms, gastropods, brackish water and symbiotic lichen habitats. Their aqueous and organic extracts were used to screen for apoptosis-inducing activity against acute myeloid leukemia cells. A total of 28 extracts showed cytotoxicity against rat acute myeloid leukemia (IPC-81 cells. The design of the screen made it possible to eliminate known toxins, such as microcystins and nodularin, or known metabolites with anti-leukemic activity, such as adenosine and its analogs. A cytotoxicity test on human embryonic kidney (HEK293T fibroblasts indicated that 21 of the 28 extracts containing anti-acute myeloid leukemia (AML activity showed selectivity in favor of leukemia cells. Extracts L26-O and L30-O were able to partly overcome the chemotherapy resistance induced by the oncogenic protein Bcl-2, whereas extract L1-O overcame protection from the deletion of the tumor suppressor protein p53. In conclusion, cyanobacteria are a prolific resource for anti-leukemia compounds that have potential for pharmaceutical applications. Based on the variety of cellular responses, we also conclude that the different anti-leukemic compounds in the cyanobacterial extracts target different elements of the death machinery of mammalian cells.

  14. Live cell imaging to understand monocyte, macrophage, and dendritic cell function in atherosclerosis.

    Science.gov (United States)

    McArdle, Sara; Mikulski, Zbigniew; Ley, Klaus

    2016-06-27

    Intravital imaging is an invaluable tool for understanding the function of cells in healthy and diseased tissues. It provides a window into dynamic processes that cannot be studied by other techniques. This review will cover the benefits and limitations of various techniques for labeling and imaging myeloid cells, with a special focus on imaging cells in atherosclerotic arteries. Although intravital imaging is a powerful tool for understanding cell function, it alone does not provide a complete picture of the cell. Other techniques, such as flow cytometry and transcriptomics, must be combined with intravital imaging to fully understand a cell's phenotype, lineage, and function.

  15. Contact-dependent depletion of hydrogen peroxide by catalase is a novel mechanism of myeloid-derived suppressor cell induction operating in human hepatic stellate cells.

    Science.gov (United States)

    Resheq, Yazid J; Li, Ka-Kit; Ward, Stephen T; Wilhelm, Annika; Garg, Abhilok; Curbishley, Stuart M; Blahova, Miroslava; Zimmermann, Henning W; Jitschin, Regina; Mougiakakos, Dimitrios; Mackensen, Andreas; Weston, Chris J; Adams, David H

    2015-03-15

    Myeloid-derived suppressor cells (MDSC) represent a unique cell population with distinct immunosuppressive properties that have been demonstrated to shape the outcome of malignant diseases. Recently, human hepatic stellate cells (HSC) have been reported to induce monocytic-MDSC from mature CD14(+) monocytes in a contact-dependent manner. We now report a novel and unexpected mechanism by which CD14(+)HLADR(low/-) suppressive cells are induced by catalase-mediated depletion of hydrogen peroxide (H2O2). Incubation of CD14(+) monocytes with catalase led to a significant induction of functional MDSC compared with media alone, and H2O2 levels inversely correlated with MDSC frequency (r = -0.6555, p Catalase was detected in primary HSC and a stromal cell line, and addition of the competitive catalase inhibitor hydroxylamine resulted in a dose-dependent impairment of MDSC induction and concomitant increase of H2O2 levels. The NADPH-oxidase subunit gp91 was significantly increased in catalase-induced MDSC as determined by quantitative PCR outlining the importance of oxidative burst for the induction of MDSC. These findings represent a so far unrecognized link between immunosuppression by MDSC and metabolism. Moreover, this mechanism potentially explains how stromal cells can induce a favorable immunological microenvironment in the context of tissue oxidative stress such as occurs during cancer therapy.

  16. Identification and functional analysis of acute myeloid leukemia susceptibility associated single nucleotide polymorphisms at non-protein coding regions of RUNX1.

    Science.gov (United States)

    Xu, Xin; Ren, Xiuyu; Wang, Haiying; Zhao, Yao; Yi, Zhengjun; Wang, Kaifeng; Zhang, Shizhuang; Wang, Lin; Samuelson, David J; Hu, Zhenbo

    2016-01-01

    Little is known about the susceptibility to acute myeloid leukemia. We aim to search non-protein coding regions of key hematopoiesis transcription factors for genetic variations associated with acute myeloid leukemia susceptibility. We genotyped SNPs of RUNX1 P1 promoter, P2 promoter, +23 enhancer, intron 5.2 enhancer, PU.1 promoter, CEBPA promoter, and CEBPE promoter from acute myeloid leukemia patients and healthy controls. Rs2249650 and rs2268276 at RUNX1 intron 5.2 enhancer were found to be associated with acute myeloid leukemia susceptibility. Artificial reporters containing different rs2249650 and rs2268276 alleles showed differential activities in the K562 cell line, a human immortalized myeloid leukemia line. Rs2249650 contributes to reporter activities more than rs2268276. Gel shift assay is consistent with the luciferase assay. Supershift assay indicated that one potential binding protein was PU.1. To sum up, rs2268276 and especially rs2249650 may be qualified as new acute myeloid leukemia susceptibility-associated SNPs.

  17. Myeloid-derived suppressor cells express Bruton’s tyrosine kinase and can be depleted in tumor bearing hosts by ibrutinib treatment

    Science.gov (United States)

    Stiff, Andrew; Trikha, Prashant; Wesolowski, Robert; Kendra, Kari; Hsu, Vincent; Uppati, Sarvani; McMichael, Elizabeth; Duggan, Megan; Campbell, Amanda; Keller, Karen; Landi, Ian; Zhong, Yiming; Dubovsky, Jason; Howard, John Harrison; Yu, Lianbo; Harrington, Bonnie; Old, Matthew; Reiff, Sean; Mace, Thomas; Tridandapani, Susheela; Muthusamy, Natarajan; Caligiuri, Michael A.; Byrd, John C.; Carson, William E.

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of immature myeloid cells that expand in tumor bearing hosts in response to soluble factors produced by tumor and stromal cells. MDSC expansion has been linked to loss of immune effector cell function and reduced efficacy of immune-based cancer therapies, highlighting the MDSC population as an attractive therapeutic target. Ibrutinib, an irreversible inhibitor of Bruton’s tyrosine kinase (BTK) and IL2-inducible T-cell kinase (ITK), is in clinical use for the treatment of B cell malignancies. Here, we report that BTK is expressed by murine and human MDSCs, and that ibrutinib is able to inhibit BTK phosphorylation in these cells. Treatment of MDSCs with ibrutinib significantly impaired nitric oxide production and cell migration. In addition, ibrutinib inhibited in vitro generation of human MDSCs and reduced mRNA expression of indolamine 2,3-dioxygenase, an immunosuppressive factor. Treatment of mice bearing EMT6 mammary tumors with ibrutinib resulted in reduced frequency of MDSCs in both the spleen and tumor. Ibrutinib treatment also resulted in a significant reduction of MDSCs in wildtype mice bearing B16F10 melanoma tumors, but not in X-linked immunodeficiency mice (XID) harboring a BTK mutation, suggesting that BTK inhibition plays an important role in the observed reduction of MDSCs in vivo. Finally, ibrutinib significantly enhanced the efficacy of anti-PD-L1 (CD274) therapy in a murine breast cancer model. Together, these results demonstrate that ibrutinib modulates MDSC function and generation, revealing a potential strategy for enhancing immune-based therapies in solid malignancies. PMID:26880800

  18. Myeloid-Derived Suppressor Cells Express Bruton's Tyrosine Kinase and Can Be Depleted in Tumor-Bearing Hosts by Ibrutinib Treatment.

    Science.gov (United States)

    Stiff, Andrew; Trikha, Prashant; Wesolowski, Robert; Kendra, Kari; Hsu, Vincent; Uppati, Sarvani; McMichael, Elizabeth; Duggan, Megan; Campbell, Amanda; Keller, Karen; Landi, Ian; Zhong, Yiming; Dubovsky, Jason; Howard, John Harrison; Yu, Lianbo; Harrington, Bonnie; Old, Matthew; Reiff, Sean; Mace, Thomas; Tridandapani, Susheela; Muthusamy, Natarajan; Caligiuri, Michael A; Byrd, John C; Carson, William E

    2016-04-15

    Myeloid-derived suppressor cells (MDSC) are a heterogeneous group of immature myeloid cells that expand in tumor-bearing hosts in response to soluble factors produced by tumor and stromal cells. MDSC expansion has been linked to loss of immune effector cell function and reduced efficacy of immune-based cancer therapies, highlighting the MDSC population as an attractive therapeutic target. Ibrutinib, an irreversible inhibitor of Bruton's tyrosine kinase (BTK) and IL2-inducible T-cell kinase (ITK), is in clinical use for the treatment of B-cell malignancies. Here, we report that BTK is expressed by murine and human MDSCs, and that ibrutinib is able to inhibit BTK phosphorylation in these cells. Treatment of MDSCs with ibrutinib significantly impaired nitric oxide production and cell migration. In addition, ibrutinib inhibited in vitro generation of human MDSCs and reduced mRNA expression of indolamine 2,3-dioxygenase, an immunosuppressive factor. Treatment of mice bearing EMT6 mammary tumors with ibrutinib resulted in reduced frequency of MDSCs in both the spleen and tumor. Ibrutinib treatment also resulted in a significant reduction of MDSCs in wild-type mice bearing B16F10 melanoma tumors, but not in X-linked immunodeficiency mice (XID) harboring a BTK mutation, suggesting that BTK inhibition plays an important role in the observed reduction of MDSCs in vivo Finally, ibrutinib significantly enhanced the efficacy of anti-PD-L1 (CD274) therapy in a murine breast cancer model. Together, these results demonstrate that ibrutinib modulates MDSC function and generation, revealing a potential strategy for enhancing immune-based therapies in solid malignancies. Cancer Res; 76(8); 2125-36. ©2016 AACR. ©2016 American Association for Cancer Research.

  19. Acute Myeloid Leukaemia of Donor Cell Origin Developing 17 Years after Allogenic Hematopoietic Cell Transplantation for Acute Promyelocytic Leukaemia

    Science.gov (United States)

    Jiménez, Pilar; Alvarez, J. Carlos; Garrido, Pilar; Lorente, J. Antonio; Palacios, Jorge; Ruiz-Cabello, Francisco

    2012-01-01

    Donor cell leukaemia (DCL) is a rare complication of allogenic hematopoietic cell transplantation (HCT). We report the case of a female patient with acute promyelocytic leukaemia (APL), FAB type M3, who developed acute myeloid leukaemia (AML) type M5 of donor origin 17 years after allogenic bone marrow transplantation (BMT) from her HLA-matched sister. Morphology and immunophenotyping showed differences with the initial leukaemia, and short tandem repeat (STR) analysis confirmed donor-type haematopoiesis. Interphase fluorescence in situ hybridisation (FISH) showed an 11q23 deletion. Given that the latency period between transplant and development of leukaemia was the longest reported to date, we discuss the mechanisms underlying delayed leukaemia onset. PMID:23675279

  20. FREQUENCIES OF PERIPHERAL BLOOD MYELOID CELLS IN HEALTHY KENYAN CHILDREN WITH α+ THALASSEMIA AND THE SICKLE CELL TRAIT

    Science.gov (United States)

    URBAN, BRITTA C.; SHAFI, MOHAMMED J.; CORDERY, DAMIEN V.; MACHARIA, ALEX; LOWE, BRETT; MARSH, KEVIN; WILLIAMS, THOMAS N.

    2009-01-01

    The high frequencies of both α+ thalassemia and the sickle cell trait (hemoglobin AS [HbAS]) found in many tropical populations are thought to reflect selection pressure from Plasmodium falciparum malaria. For HbAS, but not for α+ thalassemia, protection appears to be mediated by the enhanced phagocytic clearance of ring-infected erythrocytes. We have investigated the genotype-specific distributions of peripheral blood leukocyte populations in two groups of children living on the coast of Kenya: a group of healthy P. falciparum parasite-negative children sampled at cross-sectional survey during a period of low malaria transmission, and a group of children attending the hospital with acute malaria. We report distinctive distributions of peripheral blood myeloid dendritic cells and monocytes in children with α+ thalassemia and HbAS during healthy periods and disease, and suggest ways in which these might relate to the mechanisms of protection afforded by these conditions. PMID:16606987

  1. Activity of Bruton's tyrosine-kinase inhibitor ibrutinib in patients with CD117-positive acute myeloid leukaemia: a mechanistic study using patient-derived blast cells.

    Science.gov (United States)

    Rushworth, Stuart A; Pillinger, Genevra; Abdul-Aziz, Amina; Piddock, Rachel; Shafat, Manar S; Murray, Megan Y; Zaitseva, Lyubov; Lawes, Matthew J; MacEwan, David J; Bowles, Kristian M

    2015-05-01

    Roughly 80% of patients with acute myeloid leukaemia have high activity of Bruton's tyrosine-kinase (BTK) in their blast cells compared with normal haemopoietic cells, rendering the cells sensitive to the oral BTK inhibitor ibrutinib in vitro. We aimed to develop the biological understanding of the BTK pathway in acute myeloid leukaemia to identify clinically relevant diagnostic information that might define a subset of patients that should respond to ibrutinib treatment. We obtained acute myeloid leukaemia blast cells from unselected patients attending our UK hospital between Feb 19, 2010, and Jan 20, 2014. We isolated primary acute myeloid leukaemia blast cells from heparinised blood and human peripheral blood mononuclear cells to establish the activity of BTK in response to CD117 activation. Furthermore, we investigated the effects of ibrutinib on CD117-induced BTK activation, downstream signalling, adhesion to primary bone-marrow mesenchymal stromal cells, and proliferation of primary acute myeloid leukaemia blast cells. We used the Mann-Whitney U test to compare results between groups. We obtained acute myeloid leukaemia blast cells from 29 patients. Ibrutinib significantly inhibited CD117-mediated proliferation of primary acute myeloid leukaemia blast cells (p=0·028). CD117 activation increased BTK activity by inducing phosphorylated BTK in patients with CD117-positive acute myeloid leukaemia. Furthermore, ibrutinib inhibited CD117-induced activity of BTK and downstream kinases at a concentration of 100 nM or more. CD117-mediated adhesion of CD117-expressing blast cells to bone-marrow stromal cells was significantly inhibited by Ibrutinib at 500 nM (p=0·028) INTERPRETATION: As first-in-man clinical trials of ibrutinib in patients with acute myeloid leukaemia commence, the data suggest not all patients will respond. Our findings show that BTK has specific pro-tumoural biological actions downstream of surface CD117 activation, which are inhibited by ibrutinib

  2. A mutant RAS gene acts through protein kinase C to augment interleukin-3 dependent proliferation in a fastidious immortal myeloid cell line.

    Science.gov (United States)

    Boswell, H S; Harrington, M A; Burgess, G S; Nahreini, T L; Derigs, H G; Hodges, T D; English, D; Crean, C D; Gabig, T G

    1989-09-01

    The functional role of a mutant RAS gene in immortal myeloid cell proliferation was examined in a fastidious interleukin-3 (IL-3) dependent cell line (NFS/N1.H7) formed by forced proliferation in IL-3 of marrow cells of the NFS/N mouse. The NFS/N1.H7 cell line was strictly dependent upon IL-3 for growth, and the cell line could be activated by phorbol esters (PMA) to augment IL-3 dependent proliferation, but when pKC was downregulated, diminished IL-3 proliferative response resulted. Transfection (electroporation) of the T24 RAS-containing vector pAL8 to NFS/N1.H7 led to clones (H7 NeoRas.F3, H7 NeoRas.E2) that had incorporated the entire 6.6 Kb human mutant H-RAS genome. The mutant RAS-containing clones demonstrated greater proliferation than parent cells or cells containing a control (neo-resistance) vector over a range of suboptimal IL-3 does and in optimal IL-3 concentrations had a faster doubling rate than parent cells. The clone H7 NeoRas.F3 was studied biochemically, and found to constitutively form 3-fold more 3H-diacylglycerol than the parent cell line upon exposure to 3H-glycerol. PMA could partially repair the proliferative defect of NFS/N1.H7 compared to the RAS-expressor. These studies affirm a secondary, accelerating role for a mutant RAS gene product acting through pKC to promote clonal expansion of immortal myeloid cells stimulated by IL-3.

  3. Myeloid zinc finger 1 mediates sulindac sulfide-induced upregulation of death receptor 5 of human colon cancer cells

    OpenAIRE

    Mano Horinaka; Tatsushi Yoshida; Mitsuhiro Tomosugi; Shusuke Yasuda; Yoshihiro Sowa; Toshiyuki Sakai

    2014-01-01

    A combined therapy of sulindac sulfide and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising strategy for the treatment of cancer. Sulindac sulfide had been shown to induce the expression of death receptor 5 (DR5), a receptor for TRAIL, and sensitize cancer cells to TRAIL-induced apoptosis; however, the molecular mechanism underlying the upregulation of DR5 has not yet been elucidated. We demonstrate here that myeloid zinc finger 1 (MZF1) mediates the induction of...

  4. Development of Myelodysplastic Syndrome and Acute Myeloid Leukemia 15 Years after Hydroxyurea Use in a Patient with Sickle Cell Anemia

    OpenAIRE

    2012-01-01

    We report a 41 year old male with sickle cell disease who developed a myelodysplastic syndrome and acute myeloid leukemia with complex karyotype involving chromosomes 5, 7 and 17 after 15 years of hydroxyurea treatment. He responded poorly to induction chemotherapy with cytarabine/idarubicin followed by high dose cytarabine and succumbed to neutropenic sepsis. Multiple systematic reviews, observational studies and clinical trials were conducted to identify the toxicity profile of hydroxurea. ...

  5. An operational definition of primary refractory acute myeloid leukemia allowing early identification of patients who may benefit from allogeneic stem cell transplantation

    DEFF Research Database (Denmark)

    Ferguson, Paul; Hills, Robert K; Grech, Angela

    2016-01-01

    Up to 30% of adults with acute myeloid leukemia fail to achieve a complete remission after induction chemotherapy - termed primary refractory acute myeloid leukemia. There is no universally agreed definition of primary refractory disease, nor have the optimal treatment modalities been defined. We.......0001) cohorts. The utilization of REF1 criteria permits the early identification of patients whose outcome after one course of induction chemotherapy is very poor, and informs a novel definition of primary refractory acute myeloid leukemia. Furthermore, these data demonstrate that allogeneic stem cell...

  6. Silencing of myeloid cell leukemia-1 by small interfering RNA improves chemosensitivity to etoposide in u-937 leukemic cells.

    Science.gov (United States)

    Jafarlou, M; Baradaran, B; Shanehbandi, D; Saedi, T A; Jafarlou, V; Karimi, P; Othman, F

    2016-01-01

    A key issue in the treatment of acute myeloid leukemia (AML) is the development of drug resistance to chemotherapeutic agents. Overexpression of myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic protein, is associated with tumor progression and drug resistance in leukemia and several cancers. The purpose of this study was to investigate the effect of specific Mcl-1 small interference RNA (siRNA) on the proliferation and chemosensitivity of U-937 AML cell to etoposide. The siRNA transfection was conducted using Lipofectamine™ 2000. Quantitative real-time RT-PCR (qRT-PCR) and Western blot analysis were employed to measure the expression levels of mRNA and protein, respectively. To evaluate tumor cell growth after siRNA transfection, Trypan blue exclusion assay was conducted. The cytotoxic effects of siRNA and etoposide were determined using MTT assay on their own and in combination. DNA-histone ELISA and annexin-V/FITC assays were performed to study the apoptosis. Mcl-1 siRNA transfection significantly blocked the expression of Mcl-1 mRNA and protein in a time-dependent manner, leading to a strong growth inhibition and enhanced apoptosis (P less than 0.05). Furthermore, pretreatment with Mcl-1 siRNA, synergistically enhanced the cytotoxic and apoptotic effects of etoposide (P less than 0.05). Our results demonstrated that Mcl-1 plays a fundamental role in the survival and resistance of U-937 cells to etoposide. Therefore, Mcl-1 can be considered an attractive target in gene therapy of AML patients and siRNA-mediated silencing of this gene may be a novel strategy in AML treatment.

  7. Attenuated inflammatory response in triggering receptor expressed on myeloid cells 2 (TREM2 knock-out mice following stroke.

    Directory of Open Access Journals (Sweden)

    Matthias W Sieber

    Full Text Available BACKGROUND: Triggering receptor expressed on myeloid cells-2 (TREM2 is a microglial surface receptor involved in phagocytosis. Clearance of apoptotic debris after stroke represents an important mechanism to re-attain tissue homeostasis and thereby ensure functional recovery. The role of TREM2 following stroke is currently unclear. METHODS AND RESULTS: As an experimental stroke model, the middle cerebral artery of mice was occluded for 30 minutes with a range of reperfusion times (duration of reperfusion: 6 h/12 h/24 h/2 d/7 d/28 d. Quantitative PCR (qPCR revealed a greatly increased transcription of TREM2 after stroke. We subsequently analyzed the expression of pro-inflammatory cytokines, chemokines and their receptors in TREM2-knockout (TREM2-KO mice via qPCR. Microglial activation (CD68, Iba1 and CD3-positive T-cell invasion were analyzed via qPCR and immunohistochemistry. Functional consequences of TREM2 knockout were assessed by infarct volumetry. The acute inflammatory response (12 h reperfusion was very similar between TREM2-KO mice and their littermate controls. However, in the sub-acute phase (7 d reperfusion following stroke, TREM2-KO mice showed a decreased transcription of pro-inflammatory cytokines TNFα, IL-1α and IL-1β, associated with a reduced microglial activity (CD68, Iba1. Furthermore, TREM2-KO mice showed a reduced transcription of chemokines CCL2 (MCP1, CCL3 (MIP1α and the chemokine receptor CX3CR1, followed by a diminished invasion of CD3-positive T-cells. No effect on the lesion size was observed. CONCLUSIONS: Although we initially expected an exaggerated pro-inflammatory response following ablation of TREM2, our data support a contradictory scenario that the sub-acute inflammatory reaction after stroke is attenuated in TREM2-KO mice. We therefore conclude that TREM2 appears to sustain a distinct inflammatory response after stroke.

  8. Attenuated Inflammatory Response in Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) Knock-Out Mice following Stroke

    Science.gov (United States)

    Brehm, Martin; Guenther, Madlen; Linnartz-Gerlach, Bettina; Neumann, Harald; Witte, Otto W.; Frahm, Christiane

    2013-01-01

    Background Triggering receptor expressed on myeloid cells-2 (TREM2) is a microglial surface receptor involved in phagocytosis. Clearance of apoptotic debris after stroke represents an important mechanism to re-attain tissue homeostasis and thereby ensure functional recovery. The role of TREM2 following stroke is currently unclear. Methods and Results As an experimental stroke model, the middle cerebral artery of mice was occluded for 30 minutes with a range of reperfusion times (duration of reperfusion: 6 h/12 h/24 h/2 d/7 d/28 d). Quantitative PCR (qPCR) revealed a greatly increased transcription of TREM2 after stroke. We subsequently analyzed the expression of pro-inflammatory cytokines, chemokines and their receptors in TREM2-knockout (TREM2-KO) mice via qPCR. Microglial activation (CD68, Iba1) and CD3-positive T-cell invasion were analyzed via qPCR and immunohistochemistry. Functional consequences of TREM2 knockout were assessed by infarct volumetry. The acute inflammatory response (12 h reperfusion) was very similar between TREM2-KO mice and their littermate controls. However, in the sub-acute phase (7 d reperfusion) following stroke, TREM2-KO mice showed a decreased transcription of pro-inflammatory cytokines TNFα, IL-1α and IL-1β, associated with a reduced microglial activity (CD68, Iba1). Furthermore, TREM2-KO mice showed a reduced transcription of chemokines CCL2 (MCP1), CCL3 (MIP1α) and the chemokine receptor CX3CR1, followed by a diminished invasion of CD3-positive T-cells. No effect on the lesion size was observed. Conclusions Although we initially expected an exaggerated pro-inflammatory response following ablation of TREM2, our data support a contradictory scenario that the sub-acute inflammatory reaction after stroke is attenuated in TREM2-KO mice. We therefore conclude that TREM2 appears to sustain a distinct inflammatory response after stroke. PMID:23301011

  9. Pleiotropic effects of spongean alkaloids on mechanisms of cell death, cell cycle progression and DNA damage response (DDR) of acute myeloid leukemia (AML) cells.

    Science.gov (United States)

    Stuhldreier, Fabian; Kassel, Stefanie; Schumacher, Lena; Wesselborg, Sebastian; Proksch, Peter; Fritz, Gerhard

    2015-05-28

    We investigated cytotoxic mechanisms evoked by the spongean alkaloids aaptamine (Aa) and aeroplysinin-1 (Ap), applied alone and in combination with daunorubicin, employing acute myeloid leukemia (AML) cells. Aa and Ap reduced the viability of AML cells in a dose dependent manner with IC50 of 10-20 µM. Ap triggered apoptotic cell death more efficiently than Aa. Both alkaloids increased the protein level of S139-phosphorylated H2AX (γH2AX), which however was independent of the induction of DNA damage. Expression of the senescence markers p21 and p16 was increased, while the phosphorylation level of p-Chk-2 was reduced following Aa treatment. As a function of dose, Aa and Ap protected or sensitized AML cells against daunorubicin. Protection by Aa was paralleled by reduced formation of ROS and lower level of DNA damage. Both Aa and Ap attenuated daunorubicin-stimulated activation of the DNA damage response (DDR) as reflected on the levels of γH2AX, p-Kap-1 and p-Chk-1. Specifically Ap restored the decrease in S10 phosphorylation of histone H3 resulting from daunorubicin treatment. The cytoprotective effects of Aa and Ap were independent of daunorubicin import/export. Both Aa and Ap abrogated daunorubicin-induced accumulation of cells in S-phase. Inhibition of DNA synthesis was specific for Ap. The data show that Aa and Ap have both congruent and agent-specific pleiotropic effects that are preferential for anticancer drugs. Since Ap showed a broader spectrum of anticancer activities, this compound is suggested as novel lead compound for forthcoming in vivo studies elucidating the usefulness of spongean alkaloids in AML therapy.

  10. Identification of Extracellular Actin As a Ligand for Triggering Receptor Expressed on Myeloid Cells-1 Signaling

    Directory of Open Access Journals (Sweden)

    Lei Fu

    2017-08-01

    Full Text Available Triggering receptor expressed on myeloid cells-1 (TREM-1 is a potent amplifier of pro-inflammatory innate immune reactions, and it is an essential mediator of death in sepsis. However, the ligand for TREM-1 has not been fully identified. Previous research identified a natural ligand of TREM-1 distributed on platelets that contributed to the development of sepsis. However, the exact signal for TREM-1 recognition remains to be identified. Here, we identified actin as a TREM-1-interacting protein on platelets and found that recombinant actin could interact with recombinant TREM-1 extracellular domain directly. Furthermore, actin co-localized with TREM-1 on the surface of activated mouse macrophage RAW264.7 cells interacting with platelets. In addition, recombinant actin could enhance the inflammatory response of macrophages from wt mice but not from trem1−/− mice, and the enhancement could be inhibited by LP17 (a TREM-1 inhibitor in a dose-dependent manner. Importantly, extracellular actin showed co-localization with TREM-1 in lung tissue sections from septic mice, which suggested that TREM-1 recognized actin during activation in sepsis. Therefore, the present study identified actin as a new ligand for TREM-1 signaling, and it also provided a link between both essential regulators of death in sepsis.

  11. Therapy-related acute myeloid leukemia and myelodysplastic syndrome after hematopoietic cell transplantation for lymphoma.

    Science.gov (United States)

    Yamasaki, S; Suzuki, R; Hatano, K; Fukushima, K; Iida, H; Morishima, S; Suehiro, Y; Fukuda, T; Uchida, N; Uchiyama, H; Ikeda, H; Yokota, A; Tsukasaki, K; Yamaguchi, H; Kuroda, J; Nakamae, H; Adachi, Y; Matsuoka, K-I; Nakamura, Y; Atsuta, Y; Suzumiya, J

    2017-04-03

    Therapy-related acute myeloid leukemia and myelodysplastic syndrome (t-AML/MDS) represent severe late effects in patients receiving hematopoietic cell transplantation (HCT) for lymphoma. The choice between high-dose therapy with autologous HCT and allogeneic HCT with reduced-intensity conditioning remains controversial in patients with relapsed lymphoma. We retrospectively analyzed incidence and risk factors for the development of t-AML/MDS in lymphoma patients treated with autologous or allogeneic HCT. A total of 13 810 lymphoma patients who received autologous (n=9963) or allogeneic (n=3847) HCT between 1985 and 2012 were considered. At a median overall survival (OS) of 52 and 46 months in autologous and allogeneic HCT groups, respectively, lymphoma patients receiving autologous HCT (1.38% at 3 years after autologous HCT) had a significant risk for developing t-AML/MDS compared to allogeneic HCT (0.37% at 3 years after allogeneic HCT, Pafter autologous and allogeneic HCT were high-stage risk at HCT (P=0.04) or secondary malignancies (P<0.001) and receiving cord blood stem cell (P=0.03) or involved field radiotherapy (P=0.002), respectively. Strategies that carefully select lymphoma patients for autologous HCT, by excluding lymphoma patients with high-stage risk at HCT, may allow the identification of individual lymphoma patients at particular high risk for t-AML/MDS.Bone Marrow Transplantation advance online publication, 3 April 2017; doi:10.1038/bmt.2017.52.

  12. Cytoreduction surgery reduces systemic myeloid suppressor cell populations and restores intratumoral immunotherapy effectiveness

    Directory of Open Access Journals (Sweden)

    Predina Jarrod D

    2012-06-01

    Full Text Available Abstract Background Multiple immunotherapy approaches have improved adaptive anti-tumor immune responses in patients with early stage disease; however, results have been less dramatic when treating patients with late stage disease. These blunted responses are likely due to a host of factors, including changes in the tumor microenvironment and systemic immunosuppressive features, which accompany advanced tumor states. We hypothesized that cytoreductive surgery could control these immunosuppressive networks and restore the potency of immunotherapy in advanced disease scenarios. Methods To test these hypotheses, two representative intratumoral immunotherapies (an adenoviral vector encoding a suicide gene, AdV-tk, or a type-I interferon, Ad.IFNα were tested in murine models of lung cancer. Cytoreductive surgery was performed following treatment of advanced tumors. Mechanistic underpinnings were investigated using flow cytometry, in vivo leukocyte depletion methods and in vivo tumor neutralization assays. Results AdV-tk and Ad.IFNα were effective in treating early lung cancers, but had little anti-tumor effects in late stage cancers. Interestingly, in late stage scenarios, surgical cytoreduction unmasked the anti-tumor potency of both immunotherapeutic approaches. Immune mechanisms that explained restoration in anti-tumor immune responses included increased CD8 T-cell trafficking and reduced myeloid derived suppressor cell populations. Conclusion This study demonstrates that surgical resection combined with immunotherapy may be a rational therapeutic option for patients with advanced stage cancer.

  13. Antileukemic Potential of Momordica charantia Seed Extracts on Human Myeloid Leukemic HL60 Cells

    Directory of Open Access Journals (Sweden)

    Ramani Soundararajan

    2012-01-01

    Full Text Available Momordica charantia (bitter gourd has been used in the traditional system of medicine for the treatment of various diseases. Anticancer activity of M. charantia extracts has been demonstrated by numerous in vitro and in vivo studies. In the present study, we investigated the differentiation inducing potential of fractionated M. charantia seed extracts in human myeloid HL60 cells. We found that the HL60 cells treated with the fractionated seed extracts differentiated into granulocytic lineage as characterized by NBT staining, CD11b expression, and specific esterase activity. The differentiation inducing principle was found to be heat-stable, and organic in nature. The differentiation was accompanied by a downregulation of c-myc transcript, indicating the involvement of c-myc pathway, at least in part, in differentiation. Taken together these results indicate that fractionated extracts of M. charantia seeds possess differentiation inducing activity and therefore can be evaluated for their potential use in differentiation therapy for leukemia in combination with other inducers of differentiation.

  14. The Thoc1 encoded ribonucleoprotein is required for myeloid progenitor cell homeostasis in the adult mouse.

    Science.gov (United States)

    Pitzonka, Laura; Ullas, Sumana; Chinnam, Meenalakshmi; Povinelli, Benjamin J; Fisher, Daniel T; Golding, Michelle; Appenheimer, Michelle M; Nemeth, Michael J; Evans, Sharon; Goodrich, David W

    2014-01-01

    Co-transcriptionally assembled ribonucleoprotein (RNP) complexes are critical for RNA processing and nuclear export. RNPs have been hypothesized to contribute to the regulation of coordinated gene expression, and defects in RNP biogenesis contribute to genome instability and disease. Despite the large number of RNPs and the importance of the molecular processes they mediate, the requirements for individual RNP complexes in mammalian development and tissue homeostasis are not well characterized. THO is an evolutionarily conserved, nuclear RNP complex that physically links nascent transcripts with the nuclear export apparatus. THO is essential for early mouse embryonic development, limiting characterization of the requirements for THO in adult tissues. To address this shortcoming, a mouse strain has been generated allowing inducible deletion of the Thoc1 gene which encodes an essential protein subunit of THO. Bone marrow reconstitution was used to generate mice in which Thoc1 deletion could be induced specifically in the hematopoietic system. We find that granulocyte macrophage progenitors have a cell autonomous requirement for Thoc1 to maintain cell growth and viability. Lymphoid lineages are not detectably affected by Thoc1 loss under the homeostatic conditions tested. Myeloid lineages may be more sensitive to Thoc1 loss due to their relatively high rate of proliferation and turnover.

  15. The Thoc1 encoded ribonucleoprotein is required for myeloid progenitor cell homeostasis in the adult mouse.

    Directory of Open Access Journals (Sweden)

    Laura Pitzonka

    Full Text Available Co-transcriptionally assembled ribonucleoprotein (RNP complexes are critical for RNA processing and nuclear export. RNPs have been hypothesized to contribute to the regulation of coordinated gene expression, and defects in RNP biogenesis contribute to genome instability and disease. Despite the large number of RNPs and the importance of the molecular processes they mediate, the requirements for individual RNP complexes in mammalian development and tissue homeostasis are not well characterized. THO is an evolutionarily conserved, nuclear RNP complex that physically links nascent transcripts with the nuclear export apparatus. THO is essential for early mouse embryonic development, limiting characterization of the requirements for THO in adult tissues. To address this shortcoming, a mouse strain has been generated allowing inducible deletion of the Thoc1 gene which encodes an essential protein subunit of THO. Bone marrow reconstitution was used to generate mice in which Thoc1 deletion could be induced specifically in the hematopoietic system. We find that granulocyte macrophage progenitors have a cell autonomous requirement for Thoc1 to maintain cell growth and viability. Lymphoid lineages are not detectably affected by Thoc1 loss under the homeostatic conditions tested. Myeloid lineages may be more sensitive to Thoc1 loss due to their relatively high rate of proliferation and turnover.

  16. TCR gamma delta cytotoxic T lymphocytes expressing the killer cell-inhibitory receptor p58.2 (CD158b) selectively lyse acute myeloid leukemia cells.

    Science.gov (United States)

    Dolstra, H; Fredrix, H; van der Meer, A; de Witte, T; Figdor, C; van de Wiel-van Kemenade, E

    2001-05-01

    Cytotoxic T lymphocytes (CTL) are thought to play an important role in the graft-versus-leukemia (GVL) response. Unfortunately, GVL reactivity is often associated with life-threatening graft-versus-host disease (GVHD). Characterization of CTL that selectively attack leukemic cells but not normal cells may lead to the development of adjuvant immunotherapy that separates GVL from GVHD. Here, we describe TCR gamma delta (V gamma 9/V delta 1) CTL, isolated from the peripheral blood of an AML patient after stem cell transplantation (SCT), that very efficiently lysed freshly isolated acute myeloid leukemia (AML) cells and AML cell lines. Interestingly, HLA-matched non-malignant hematopoietic cells were not killed. We revealed that the killer cell-inhibitory receptor (KIR) p58.2 (CD158b) specific for group 2 HLA-C molecules negatively regulates the cytotoxic effector function displayed by these TCR gamma delta CTL. First, an antibody against HLA-C enhances lysis of non-malignant cells. Secondly, stable transfection of HLA-Cw*0304 into the class I-negative cell line 721.221 inhibited lysis. Finally, engagement of p58.2 by antibodies immobilized on Fc gamma R-expressing murine P815 cells inhibits CD3- and TCR gamma delta-directed lysis. Compared to non-malignant hematopoietic cells, AML cells express much lower levels of MHC class I molecules making them susceptible to lysis by p58.2(+) TCR gamma delta CTL. Such KIR-regulated CTL reactivity may have a role in the GVL response without affecting normal tissues of the host and leading to GVHD.

  17. Concurrent targeting Akt and sphingosine kinase 1 by A-674563 in acute myeloid leukemia cells

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    Xu, Lin [Xiangya Hospital, Central South University, Changsha (China); Shaoyang Central Hospital, Hunan Province (China); Zhang, Yanan; Gao, Meng [The Third Xiangya Hospital, Central South University, Changsha, 410013 (China); Wang, Guangping, E-mail: wangguangping45@sina.com [Xiangya Hospital, Central South University, Changsha (China); Fu, Yunfeng, E-mail: fuyunfeng33163@163.com [The Third Xiangya Hospital, Central South University, Changsha, 410013 (China)

    2016-04-15

    Akt signaling plays a pivotal role in acute myeloid leukemia (AML) development and progression. In the present study, we evaluated the potential anti-AML activity by a novel Akt kinase inhibitor A-674563. Our results showed that A-674563 dose-dependently inhibited survival and proliferation of U937 AML cells and six lines of human AML progenitor cells, yet sparing human peripheral blood mononuclear leukocytes (PBMCs). A-674563 activated caspase-3/9 and apoptosis in the AML cells. Reversely, the pan-caspase inhibitor z-VAD-CHO dramatically alleviated A-674563-induced AML cell apoptosis and cytotoxicity. For the molecular study, we showed that A-674563 blocked Akt activation in U937 cells and human AML progenitor cells. Further, A-674563 decreased sphingosine kinase 1 (SphK1) activity in above AML cells to deplete pro-survival sphingosine-1-phosphate (S1P) and boost pro-apoptotic ceramide production. Such an effect on SphK1 signaling by A-674563 appeared independent of Akt blockage. Significantly, K6PC-5, a novel SphK1 activator, or supplement with S1P attenuated A-674563-induced ceramide production, and subsequent U937 cell death and apoptosis. Importantly, intraperitoneal injection of A-674563 at well-tolerated doses suppressed U937 leukemic xenograft tumor growth in nude mice, whiling significantly improving the animal survival. The results of the current study demonstrate that A-674563 exerts potent anti-leukemic activity in vitro and in vivo, possibly via concurrent targeting Akt and SphK1 signalings. - Highlights: • A-674563 is cytotoxic and anti-proliferative in U937 and AML progenitor cells. • A-674563 activates caspase-3/9 and apoptosis in U937 and AML progenitor cells. • Whiling blocking Akt, A-674563 manipulates other signalings in AML cells. • A-674563 inhibits SphK1 activity in AML cells, independent of Akt blockage. • A-674563 injection inhibits U937 xenograft in vivo growth, and improves mice survival.

  18. Immunosuppressive activity enhances central carbon metabolism and bioenergetics in myeloid-derived suppressor cells in vitro models

    Directory of Open Access Journals (Sweden)

    Hammami Ines

    2012-07-01

    Full Text Available Abstract Background The tumor microenvironment contains a vast array of pro- and anti-inflammatory cytokines that alter myelopoiesis and lead to the maturation of immunosuppressive cells known as myeloid-derived suppressor cells (MDSCs. Incubating bone marrow (BM precursors with a combination of granulocyte-macrophage colony-stimulating factor (GM-CSF and interleukin-6 (IL-6 generated a tumor-infiltrating MDSC-like population that impaired anti-tumor specific T-cell functions. This in vitro experimental approach was used to simulate MDSC maturation, and the cellular metabolic response was then monitored. A complementary experimental model that inhibited L-arginine (L-Arg metabolizing enzymes in MSC-1 cells, an immortalized cell line derived from primary MDSCs, was used to study the metabolic events related to immunosuppression. Results Exposure of BM cells to GM-CSF and IL-6 activated, within 24 h, L-Arg metabolizing enzymes which are responsible for the MDSCs immunosuppressive potential. This was accompanied by an increased uptake of L-glutamine (L-Gln and glucose, the latter being metabolized by anaerobic glycolysis. The up-regulation of nutrient uptake lead to the accumulation of TCA cycle intermediates and lactate as well as the endogenous synthesis of L-Arg and the production of energy-rich nucleotides. Moreover, inhibition of L-Arg metabolism in MSC-1 cells down-regulated central carbon metabolism activity, including glycolysis, glutaminolysis and TCA cycle activity, and led to a deterioration of cell bioenergetic status. The simultaneous increase of cell specific concentrations of ATP and a decrease in ATP-to-ADP ratio in BM-derived MDSCs suggested cells were metabolically active during maturation. Moreover, AMP-activated protein kinase (AMPK was activated during MDSC maturation in GM-CSF and IL-6–treated cultures, as revealed by the continuous increase of AMP-to-ATP ratios and the phosphorylation of AMPK. Likewise, AMPK activity was

  19. miR-9/9* in Myeloid Development and Acute Myeloid Leukemia

    NARCIS (Netherlands)

    K. Nowek (Katarzyna)

    2017-01-01

    markdownabstractmiR-9/9* have been shown to be deregulated in different types of human cancer including lymphoid and myeloid malignancies. Nevertheless, we still lack the more comprehensive knowledge about the impact of miR-9/9* expression on normal hematopoietic cell function and their possible

  20. Transcriptional activation of hypoxia-inducible factor-1 (HIF-1) in myeloid cells promotes angiogenesis through VEGF and S100A8.

    Science.gov (United States)

    Ahn, G-One; Seita, Jun; Hong, Beom-Ju; Kim, Young-Eun; Bok, Seoyeon; Lee, Chan-Ju; Kim, Kwang Soon; Lee, Jerry C; Leeper, Nicholas J; Cooke, John P; Kim, Hak Jae; Kim, Il Han; Weissman, Irving L; Brown, J Martin

    2014-02-18

    Emerging evidence indicates that myeloid cells are essential for promoting new blood vessel formation by secreting various angiogenic factors. Given that hypoxia-inducible factor (HIF) is a critical regulator for angiogenesis, we questioned whether HIF in myeloid cells also plays a role in promoting angiogenesis. To address this question, we generated a unique strain of myeloid-specific knockout mice targeting HIF pathways using human S100A8 as a myeloid-s