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Pei J, Tang Z, Zang G, Yu Y. Blockage of Notch1 signaling modulates the T-helper (Th)1/Th2 cell balance in chronic hepatitis B patients. Hepatol Res 2010; 40:799-805. [PMID: 20626467 DOI: 10.1111/j.1872-034x.2010.00680.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
AIM Chronic hepatitis B virus (HBV) infection is thought to involve the imbalance of T-helper (Th)1/Th2 cells. Many procedures found Notch signaling involved the proliferation and differentiation of T lymphocytes during development and peripheral functions. The aim of this study was to discover the effect of blockage of Notch1 signaling to Th cells and the mechanisms involved in chronic hepatitis B patients. METHODS CD4(+) T cells from hepatitis B patients and healthy volunteers were isolated, and Notch1 expression of CD4(+) T cells was determined by reverse transcription polymerase chain reaction (RT-PCR). Blockage of Notch1 signaling of peripheral blood mononuclear cells (PBMC) from chronic hepatitis B patients, Th1- and Th2-type cytokines were assayed by enzyme-linked immunosorbent assay and levels of T-bet, GATA-3 mRNA were measured by RT-PCR. RESULTS Notch1 expression of CD4(+) T cells from chronic hepatitis B patients was upregulated, on the contrary to that from acute hepatitis B patients and healthy volunteers. Blockage of Notch1 signaling can strongly inhibit the production of Th2-type cytokines and the expression of GATA-3; the production of Th1-type cytokines and the expression of T-bet, however, were enhanced. CONCLUSION Blockage of Notch1 signaling could regulate the immune balance of Th1/Th2 in chronic hepatitis B patients, which may be mediated partly by regulating transcription factors T-bet and GATA-3.
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Affiliation(s)
- Jinxian Pei
- Department of Infectious Diseases, Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, China
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52
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Abstract
Deregulation of Notch signaling has been linked to the development of T-cell leukemias and several solid malignancies. Yet, it is unknown whether Notch signaling is involved in the pathogenesis of mycosis fungoides and Sézary syndrome, the most common subtypes of cutaneous T-cell lymphoma. By immunohistochemistry of 40 biopsies taken from skin lesions of mycosis fungoides and Sézary syndrome, we demonstrated prominent expression of Notch1 on tumor cells, especially in the more advanced stages. The γ-secretase inhibitor I blocked Notch signaling and potently induced apoptosis in cell lines derived from mycosis fungoides (MyLa) and Sézary syndrome (SeAx, HuT-78) and in primary leukemic Sézary cells. Specific down-regulation of Notch1 (but not Notch2 and Notch3) by siRNA induced apoptosis in SeAx. The mechanism of apoptosis involved the inhibition of nuclear factor-κB, which is the most important prosurvival pathway in cutaneous T-cell lymphoma. Our data show that Notch is present in cutaneous T-cell lymphoma and that its inhibition may provide a new way to treat cutaneous T-cell lymphoma.
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53
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Griffith AV, Fallahi M, Nakase H, Gosink M, Young B, Petrie HT. Spatial mapping of thymic stromal microenvironments reveals unique features influencing T lymphoid differentiation. Immunity 2010; 31:999-1009. [PMID: 20064453 DOI: 10.1016/j.immuni.2009.09.024] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Revised: 09/16/2009] [Accepted: 09/23/2009] [Indexed: 01/16/2023]
Abstract
Interaction of hematopoietic progenitors with the thymic microenvironment induces them to proliferate, adopt the T lineage fate, and asymmetrically diverge into multiple functional lineages. Progenitors at various developmental stages are stratified within the thymus, implying that the corresponding microenvironments provide distinct sets of signals to progenitors migrating between them. These differences remain largely undefined. Here we used physical and computational approaches to generate a comprehensive spatial map of stromal gene expression in the thymus. Although most stromal regions were characterized by a unique gene expression signature, the central cortex lacked distinctive features. Instead, a key function of this region appears to be the sequestration of unique microenvironments found at the cortical extremities, thus modulating the relative proximity of progenitors moving between them. Our findings compel reexamination of how cell migration, lineage specification, and proliferation are controlled by thymic architecture and provide an in-depth resource for global characterization of this control.
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Affiliation(s)
- Ann V Griffith
- Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA
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54
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Abstract
Notch signaling is an important molecular pathway involved in the determination of cell fate. In recent years, this signaling has been frequently reported to play a critical role in maintaining progenitor/stem cell population as well as a balance between cell proliferation, differentiation and apoptosis. Thus, Notch signaling may be mechanistically involved carcinogenesis. Indeed, many studies have showed that Notch signaling is overexpressed or constitutively activated in many cancers including colorectal cancer (CRC). Consequently, inactivation of Notch signaling may constitute a novel molecular therapy for cancer. CRC is one of the most common malignancies but the current therapeutic approaches for advanced CRC are less efficient. Thus, novel therapeutic approaches are badly needed. In this review article, the authors reviewed the current understanding and research findings of the role of Notch signaling in CRC and discussed the possible Notch-targeting approaches in CRC.
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Affiliation(s)
- Liang Qiao
- Department of Medicine and Centre for Cancer Research, The University of Hong Kong, Queen Mary Hospital, Hong Kong
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55
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Tremblay CS, Hoang T, Hoang T. Early T cell differentiation lessons from T-cell acute lymphoblastic leukemia. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 92:121-56. [PMID: 20800819 DOI: 10.1016/s1877-1173(10)92006-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
T cells develop from bone marrow-derived self-renewing hematopoietic stem cells (HSC). Upon entering the thymus, these cells undergo progressive commitment and differentiation driven by the thymic stroma and the pre-T cell receptor (pre-TCR). These processes are disrupted in T-cell acute lymphoblastic leukemia (T-ALL). More than 70% of recurring chromosomal rearrangements in T-ALL activate the expression of oncogenic transcription factors, belonging mostly to three families, basic helix-loop-helix (bHLH), homeobox (HOX), and c-MYB. This prevalence is indicative of their importance in the T lineage, and their dominant mechanisms of transformation. For example, bHLH oncoproteins inhibit E2A and HEB, revealing their tumor suppressor function in the thymus. The induction of T-ALL, nonetheless, requires collaboration with constitutive NOTCH1 signaling and the pre-TCR, as well as loss-of-function mutations for CDKN2A and PTEN. Significantly, NOTCH1, the pre-TCR pathway, and E2A/HEB proteins control critical checkpoints and branchpoints in early thymocyte development whereas several oncogenic transcription factors, HOXA9, c-MYB, SCL, and LYL-1 control HSC self-renewal. Together, these genetic lesions alter key regulatory processes in the cell, favoring self-renewal and subvert the normal control of thymocyte homeostasis.
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Affiliation(s)
- Cédric S Tremblay
- Institute of Research in Immunology and Cancer, University of Montreal, Montréal, Québec, Canada
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56
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Abstract
Because of its multiple effects in tissue homeostasis and cancer, Notch signaling is gaining increasing attention as a potential therapeutic target. Notch proteins belong to a family of highly conserved cell surface receptors. Ligand binding leads to proteolytic cleavage of Notch receptors by the gamma-secretase complex, followed by translocation of the active intracellular Notch domain into the nucleus and transcriptional activation. Multiple genetic and pharmacological methods are available to inhibit or activate the Notch pathway, some of which are entering human clinical trials. In this review, we discuss our current understanding of Notch signaling in the hematopoietic system. Canonical Notch signaling is essential for the generation of definitive embryonic hematopoietic stem cells, but dispensable for their maintenance during adult life. Notch controls several early steps of T cell development, as well as specific cell fate and differentiation decisions in other hematopoietic lineages. In addition, emerging evidence indicates that Notch is a potent, context-specific regulator of T cell immune responses, including in several disease models relevant to patients. This knowledge will constitute a framework to explore Notch modulation as a therapeutic strategy and to understand potential hematopoietic side effects of systemic Notch inhibition.
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Affiliation(s)
- Ashley R Sandy
- University of Michigan, Center for Stem Cell Biology, Life Sciences Institute, Ann Arbor, MI 48109, USA
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57
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Souza-e-Silva H, Savino W, Feijóo RA, Vasconcelos ATR. A cellular automata-based mathematical model for thymocyte development. PLoS One 2009; 4:e8233. [PMID: 20011042 PMCID: PMC2784945 DOI: 10.1371/journal.pone.0008233] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Accepted: 10/29/2009] [Indexed: 11/26/2022] Open
Abstract
Intrathymic T cell development is an important process necessary for the normal formation of cell-mediated immune responses. Importantly, such a process depends on interactions of developing thymocytes with cellular and extracellular elements of the thymic microenvironment. Additionally, it includes a series of oriented and tunely regulated migration events, ultimately allowing mature cells to cross endothelial barriers and leave the organ. Herein we built a cellular automata-based mathematical model for thymocyte migration and development. The rules comprised in this model take into account the main stages of thymocyte development, two-dimensional sections of the normal thymic microenvironmental network, as well as the chemokines involved in intrathymic cell migration. Parameters of our computer simulations with further adjusted to results derived from previous experimental data using sub-lethally irradiated mice, in which thymus recovery can be evaluated. The model fitted with the increasing numbers of each CD4/CD8-defined thymocyte subset. It was further validated since it fitted with the times of permanence experimentally ascertained in each CD4/CD8-defined differentiation stage. Importantly, correlations using the whole mean volume of young normal adult mice revealed that the numbers of cells generated in silico with the mathematical model fall within the range of total thymocyte numbers seen in these animals. Furthermore, simulations made with a human thymic epithelial network using the same mathematical model generated similar profiles for temporal evolution of thymocyte developmental stages. Lastly, we provided in silico evidence that the thymus architecture is important in the thymocyte development, since changes in the epithelial network result in different theoretical profiles for T cell development/migration. This model likely can be used to predict thymocyte evolution following therapeutic strategies designed for recovery of the thymus in diseases coursing with thymus involution, such as some primary immunodeficiencies, acute infections, and malnutrition.
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Affiliation(s)
| | - Wilson Savino
- Laboratory of Thymus Research, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
- * E-mail:
| | - Raúl A. Feijóo
- Computer Science Coordination, LNCC/MCT, Petrópolis, Brazil
- National Institute of Science and Technology for Medicine Assisted by Scientific Computing, INCT-MACC, Petrópolis, Brazil
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58
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Abstract
Notch signaling controls numerous cell-fate specification events in multicellular organisms, and dysregulated Notch signaling causes several diseases with underlying developmental defects. A key step in Notch receptor activation is its intramembrane proteolysis, which releases an intracellular fragment that participates directly in transcriptional regulation of nuclear target genes. Despite the apparent simplicity of this mechanism, a host of posttranslational processes regulate Notch activity during its synthesis and secretion, ligand-dependent activation at the surface, endocytic trafficking, and degradation. This review describes the core developmental logic of Notch signaling and how regulatory mechanisms tailor Notch pathway outputs to specific developmental scenarios.
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Affiliation(s)
- Mark E Fortini
- Department of Biochemistry and Molecular Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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59
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Cullion K, Draheim KM, Hermance N, Tammam J, Sharma VM, Ware C, Nikov G, Krishnamoorthy V, Majumder PK, Kelliher MA. Targeting the Notch1 and mTOR pathways in a mouse T-ALL model. Blood 2009; 113:6172-81. [PMID: 19246562 PMCID: PMC2699237 DOI: 10.1182/blood-2008-02-136762] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Accepted: 01/30/2009] [Indexed: 12/23/2022] Open
Abstract
Mutations in NOTCH1 are frequently detected in patients with T-cell acute lymphoblastic leukemia (T-ALL) and in mouse T-ALL models. Treatment of mouse or human T-ALL cell lines in vitro with gamma-secretase inhibitors (GSIs) results in growth arrest and/or apoptosis. These studies suggest GSIs as potential therapeutic agents in the treatment of T-ALL. To determine whether GSIs have antileukemic activity in vivo, we treated near-end-stage Tal1/Ink4a/Arf+/- leukemic mice with vehicle or with a GSI developed by Merck (MRK-003). We found that GSI treatment significantly extended the survival of leukemic mice compared with vehicle-treated mice. Notch1 target gene expression was repressed and increased numbers of apoptotic cells were observed in the GSI-treated mice, demonstrating that Notch1 inhibition in vivo induces apoptosis. T-ALL cell lines also exhibit PI3K/mTOR pathway activation, indicating that rapamycin may also have therapeutic benefit. When GSIs are administered in combination with rapamycin, mTOR kinase activity is ablated and apoptosis induced. Moreover, GSI and rapamycin treatment inhibits human T-ALL growth and extends survival in a mouse xenograft model. This work supports the idea of targeting NOTCH1 in T-ALL and suggests that inhibition of the mTOR and NOTCH1 pathways may have added efficacy.
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Affiliation(s)
- Kathleen Cullion
- Department of Cancer Biology and the Cancer Center, University of Massachusetts Medical School, Worcester, MA 01605, USA
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60
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Purow B. Notch inhibitors as a new tool in the war on cancer: a pathway to watch. Curr Pharm Biotechnol 2009; 10:154-60. [PMID: 19199947 DOI: 10.2174/138920109787315060] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Notch was first recognized as an important developmental pathway in Drosophila in the first half of the 20th century. Many decades later, this pathway has been found to play central roles in humans in stem cell maintenance, cell fate decisions, and in cancer as well. Notch family members are being revealed as oncogenes in an ever-increasing number of cancers. Though significant progress has been made in dissecting the complex workings of this signaling pathway, there are very limited options available for Notch inhibitors. However, the pioneering class of Notch inhibitors is already in clinical trials for two cancer types. This review will address the current state-of-the-art, agents in the pipeline, and potential strategies for future Notch inhibitors. Successful development of Notch inhibitors in the clinic holds great promise as a new anti-cancer strategy.
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Affiliation(s)
- Benjamin Purow
- Neuro-Oncology Division, Neurology Department, University of Virginia, Charlottesville, VA, USA.
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61
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Zhang Z, Zeng B, Zhang Z, Jiao G, Li H, Jing Z, Ouyang J, Yuan X, Chai L, Che Y, Zhang Y, Yang R. Suppressor of Cytokine Signaling 3 Promotes Bone Marrow Cells to Differentiate into CD8+ T Lymphocytes in Lung Tissue via Up-Regulating Notch1 Expression. Cancer Res 2009; 69:1578-86. [DOI: 10.1158/0008-5472.can-08-2744] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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62
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Teitell MA, Pandolfi PP. Molecular Genetics of Acute Lymphoblastic Leukemia. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2009; 4:175-98. [DOI: 10.1146/annurev.pathol.4.110807.092227] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Michael A. Teitell
- Departments of Pathology and Pediatrics, Jonsson Comprehensive Cancer Center, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, and California NanoSystems Institute, David Geffen School of Medicine, University of California, Los Angeles, California 90095-1732;
| | - Pier Paolo Pandolfi
- Departments of Medicine and Pathology, Harvard Medical School, Boston, Massachusetts 02115
- Division of Cancer Genetics and Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215;
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63
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Mechanisms regulating the susceptibility of hematopoietic malignancies to glucocorticoid-induced apoptosis. Adv Cancer Res 2009; 101:127-248. [PMID: 19055945 DOI: 10.1016/s0065-230x(08)00406-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Glucocorticoids (GCs) are commonly used in the treatment of hematopoietic malignancies owing to their ability to induce apoptosis of these cancerous cells. Whereas some types of lymphoma and leukemia respond well to this drug, others are resistant. Also, GC-resistance gradually develops upon repeated treatments ultimately leading to refractory relapsed disease. Understanding the mechanisms regulating GC-induced apoptosis is therefore uttermost important for designing novel treatment strategies that overcome GC-resistance. This review discusses updated data describing the complex regulation of the cell's susceptibility to apoptosis triggered by GCs. We address both the genomic and nongenomic effects involved in promoting the apoptotic signals as well as the resistance mechanisms opposing these signals. Eventually we address potential strategies of clinical relevance that sensitize GC-resistant lymphoma and leukemia cells to this drug. The major target is the nongenomic signal transduction machinery where the interplay between protein kinases determines the cell fate. Shifting the balance of the kinome towards a state where Glycogen synthase kinase 3alpha (GSK3alpha) is kept active, favors an apoptotic response. Accumulating data show that it is possible to therapeutically modulate GC-resistance in patients, thereby improving the response to GC therapy.
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64
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Notch signaling inhibits the growth of the human chronic myeloid leukemia cell line K562. Leuk Res 2009; 33:109-14. [DOI: 10.1016/j.leukres.2008.06.023] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2008] [Revised: 06/16/2008] [Accepted: 06/22/2008] [Indexed: 01/30/2023]
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65
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Hutton JF, Gargett T, Sadlon TJ, Bresatz S, Brown CY, Zola H, Shannon MF, D'Andrea RJ, Barry SC. Development of CD4+CD25+FoxP3+ regulatory T cells from cord blood hematopoietic progenitor cells. J Leukoc Biol 2008; 85:445-51. [PMID: 19103952 DOI: 10.1189/jlb.1008620] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Adult stem cells are capable of generating all of the cells of the hematopoietic system, and this process is orchestrated in part by the interactions between these cells and the stroma. T cell progenitors emerge from the stem cell compartment and migrate to the thymus, where their terminal differentiation and maturation occur, and it is during this phase that selection shapes the immune repertoire. Notch ligands, including Delta-like 1 (DL1), play a critical role in this lymphoid differentiation. To mimic this in vitro, stroma-expressing DL1 have been used to generate CD4(+)CD8(+) double-positive and single-positive T cells from hematopoietic stem/progenitor cells. This system provides a robust tool to investigate thymopoiesis; however, its capacity to generate regulatory T cells (Tregs) has yet to be reported. Natural Tregs (nTregs) develop in the thymus and help maintain immune homeostasis and have potential clinical use as a cell therapy for modulation of autoimmune disease or for transplant tolerization. Here, we describe for the first time the development of a population of CD4(+)CD25(+) CD127(lo)FoxP3(+) cells that emerge in coculture of cord blood (CB) CD34(+) progenitors on OP9-DL1 stroma. These hematopoietic progenitor-derived CD4(+)CD25(+) Tregs have comparable suppressor function with CB nTregs in vitro. The addition of IL-2 to the coculture enhanced the expansion and survival of this population significantly. This manipulable culture system, therefore, generates functional Tregs and provides a system to elucidate the mechanism of Treg development.
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Affiliation(s)
- Jonathon F Hutton
- Molecular Immunology Laboratory, Discipline of Paediatrics, University of Adelaide, North Adelaide, South Australia 5006
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66
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Andaloussi AE, Han Y, Lesniak MS. Progression of intracranial glioma disrupts thymic homeostasis and induces T-cell apoptosis in vivo. Cancer Immunol Immunother 2008; 57:1807-16. [PMID: 18392618 PMCID: PMC11030257 DOI: 10.1007/s00262-008-0508-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Accepted: 03/24/2008] [Indexed: 12/01/2022]
Abstract
The thymus is the site where all T-cell precursors develop, mature, and subsequently leave as mature T-cells. Since the mechanisms that mediate and regulate thymic apoptosis are not fully understood, we utilized a syngenic GL261 murine glioma model to further elucidate the fate of T-cells in tumor bearing C57BL/6 mice. First, we found a dramatic reduction in the size of the thymus accompanied by a decrease in thymic cellularity in response to glioma growth in the brains of affected mice. There was a marked reduction of double positive subset and an increase in the frequency of CD4(+) and CD8(+) single positive T-cell subsets. Analysis of double negative thymocytes showed an increase in the accumulation of CD44(+) cells. In contrast, there was a marked loss of CD44 and CD122 expression in CD4(+) and CD8(+) subsets. The growth of intracranial tumors was also associated with decreased levels of HO-1, a mediator of anti-apoptotic function, and increased levels of Notch-1 and its ligand, Jagged-1. To determine whether thymic atrophy could be due to the effect of Notch and its ligand expression by glioma in vivo, we performed a bone marrow transplant experiment. Our results suggest that Notch-1 and its ligand Jagged-1 can induce apoptosis of thymocytes, thereby influencing thymic development, immune system homeostasis, and function of the immune cells in a model of experimental glioma.
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Affiliation(s)
- Abdeljabar El Andaloussi
- The Brain Tumor Center, The University of Chicago, 5841 S. Maryland Ave MC 3026, Chicago, IL 60637 USA
- Division of Neurosurgery and Neuro-oncology, Faculty of Medicine and Health Science, The University of Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, QC J1H 5N4 Canada
| | - Yu Han
- The Brain Tumor Center, The University of Chicago, 5841 S. Maryland Ave MC 3026, Chicago, IL 60637 USA
| | - Maciej S. Lesniak
- The Brain Tumor Center, The University of Chicago, 5841 S. Maryland Ave MC 3026, Chicago, IL 60637 USA
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67
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Abstract
Glycosylation produces a diverse and abundant repertoire of glycans, which are collectively known as the glycome. Glycans are one of the four fundamental macromolecular components of all cells, and are highly regulated in the immune system. Their diversity reflects their multiple biological functions that encompass ligands for proteinaceous receptors known as lectins. Since the discovery that selectins and their glycan ligands are important for the regulation of leukocyte trafficking, it has been shown that additional features of the vertebrate immune system are also controlled by endogenous cellular glycosylation. This Review focuses on the emerging immunological roles of the mammalian glycome.
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68
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Park JT, Shih IM, Wang TL. Identification of Pbx1, a potential oncogene, as a Notch3 target gene in ovarian cancer. Cancer Res 2008; 68:8852-60. [PMID: 18974129 PMCID: PMC2636690 DOI: 10.1158/0008-5472.can-08-0517] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Notch3 gene amplification has recently been identified in ovarian cancer but the Notch3 effectors that are involved in the development of ovarian cancer remain elusive. In this study, we have identified Pbx1, a proto-oncogene in hematopoietic malignancy, as a Notch3 target gene. Pbx1 expression is transcriptionally regulated by Notch3 activation, and Notch3/CSL protein complex directly binds to the Pbx1 promoter segment harboring the CSL-binding sequence. The growth-inhibitory effect of gamma-secretase inhibitor could be partially reversed by ectopic Pbx1 expression. Furthermore, functional studies by Pbx1 short hairpin RNA knockdown show that Pbx1 is essential for cell proliferation and tumorigenicity. Taken together, the above findings indicate that Pbx1 is a direct Notch3-regulated gene that mediates the survival signal of Notch3 in ovarian cancer.
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Affiliation(s)
- Joon T Park
- Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland
- Pathobiology Graduate Program, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Ie-Ming Shih
- Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland
- Department of Oncology, Gynecology and Obstetrics, Johns Hopkins Medical Institutions, Baltimore, Maryland
- Pathobiology Graduate Program, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Tian-Li Wang
- Department of Oncology, Gynecology and Obstetrics, Johns Hopkins Medical Institutions, Baltimore, Maryland
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69
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Yang B, Gay DL, MacLeod MKL, Cao X, Hala T, Sweezer EM, Kappler J, Marrack P, Oliver PM. Nedd4 augments the adaptive immune response by promoting ubiquitin-mediated degradation of Cbl-b in activated T cells. Nat Immunol 2008; 9:1356-63. [PMID: 18931680 DOI: 10.1038/ni.1670] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Accepted: 09/30/2008] [Indexed: 11/09/2022]
Abstract
Nedd4 and Itch are E3 ubiquitin ligases that ubiquitinate similar targets in vitro and thus are thought to function similarly. T cells lacking Itch show spontaneous activation and T helper type 2 polarization. To test whether loss of Nedd4 affects T cells in the same way, we generated Nedd4(+/+) and Nedd4(-/-) fetal liver chimeras. Nedd4(-/-) T cells developed normally but proliferated less, produced less interleukin 2 and provided inadequate help to B cells. Nedd4(-/-) T cells contained more of the E3 ubiquitin ligase Cbl-b, and Nedd4 was required for polyubiquitination of Cbl-b induced by CD28 costimulation. Our data demonstrate that Nedd4 promotes the conversion of naive T cells into activated T cells. We propose that Nedd4 and Itch ubiquitinate distinct target proteins in vivo.
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Affiliation(s)
- Baoli Yang
- Department of Obstetrics and Gynecology, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA
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70
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Mesenchymal stem cells induce mature dendritic cells into a novel Jagged-2-dependent regulatory dendritic cell population. Blood 2008; 113:46-57. [PMID: 18832657 DOI: 10.1182/blood-2008-04-154138] [Citation(s) in RCA: 241] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Mesenchymal stem cells (MSCs), in addition to their multilineage differentiation, exert immunomodulatory effects on immune cells, even dendritic cells (DCs). However, whether they influence the destiny of full mature DCs (maDCs) remains controversial. Here we report that MSCs vigorously promote proliferation of maDCs, significantly reduce their expression of Ia, CD11c, CD80, CD86, and CD40 while increasing CD11b expression. Interestingly, though these phenotypes clearly suggest their skew to immature status, bacterial lipopolysaccharide (LPS) stimulation could not reverse this trend. Moreover, high endocytosic capacity, low immunogenicity, and strong immunoregulatory function of MSC-treated maDCs (MSC-DCs) were also observed. Furthermore we found that MSCs, partly via cell-cell contact, drive maDCs to differentiate into a novel Jagged-2-dependent regulatory DC population and escape their apoptotic fate. These results further support the role of MSCs in preventing rejection in organ transplantation and treatment of autoimmune disease.
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71
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Tian L, Wu X, Chi C, Han M, Xu T, Zhuang Y. ADAM10 is essential for proteolytic activation of Notch during thymocyte development. Int Immunol 2008; 20:1181-7. [PMID: 18635581 DOI: 10.1093/intimm/dxn076] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Notch signaling pathway has been shown to play essential roles in T lymphocyte development. Activation of Notch requires a sequential proteolytic cleavage, which converts Notch from the full-length membrane-bound form to a transcriptionally active intracellular fragment. Studies in Drosophila showed that Kuzbanian (Kuz) is responsible for the enzymatic cleavage of extracellular S2 site upon Notch binding to its ligand Delta. Both a disintegrin and metalloprotease (ADAM) 10 and ADAM17, members of the ADAM family metalloproteases, have been indicated as the mammalian counterpart of Kuz in activating Notch in mammals. Here, we investigated functions of ADAM10 in Notch signaling during thymocyte development. We show that conditional disruption of the Adam10 gene in mouse thymocytes results in a developmental defect similar to the phenotypes previously described for T lineage-specific disruption of Notch1. We further show that the activation of Notch1 and its downstream target genes Deltex-1 and Pre-Ta are impaired in Adam10-deficient thymocytes. Our study demonstrates a T cell intrinsic role for Adam10 in activation of Notch1 during thymocyte development.
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Affiliation(s)
- Lei Tian
- Institute of Developmental Biology and Molecular Medicine, School of Life Sciences, Fudan University, Shanghai 200433, China
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72
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Abstract
T-cell acute lymphoblastic leukaemia (T-ALL) is induced by the transformation of T-cell progenitors and mainly occurs in children and adolescents. Although treatment outcome in patients with T-ALL has improved in recent years, patients with relapsed disease continue to have a poor prognosis. It is therefore important to understand the molecular pathways that control both the induction of transformation and the treatment of relapsed disease. In this Review, we focus on the molecular mechanisms responsible for disease induction and maintenance. We also compare the physiological progression of T-cell differentiation with T-cell transformation, highlighting the close relationship between these two processes. Finally, we discuss potential new therapies that target oncogenic pathways in T-ALL.
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73
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Histochemical and molecular overview of the thymus as site for T-cells development. ACTA ACUST UNITED AC 2008; 43:73-120. [PMID: 18555891 DOI: 10.1016/j.proghi.2008.03.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Accepted: 03/11/2008] [Indexed: 12/19/2022]
Abstract
The thymus represents the primary site for T cell lymphopoiesis, providing a coordinated set for critical factors to induce and support lineage commitment, differentiation and survival of thymus-seeding cells. One irrefutable fact is that the presence of non-lymphoid cells through the thymic parenchyma serves to provide coordinated migration and differentiation of T lymphocytes. Moreover, the link between foetal development and normal anatomy has been stressed in this review. Regarding thymic embryology, its epithelium is derived from the embryonic endodermal layer, with possible contributions from the ectoderm. A series of differentiating steps is essential, each of which must be completed in order to provide the optimum environment for thymic development and function. The second part of this article is focused on thymic T-cell development and differentiation, which is a stepwise process, mediated by a variety of stromal cells in different regions of the organ. It depends strongly on the thymic microenvironment, a cellular network formed by epithelial cells, macrophages, dendritic cells and fibroblasts, that provide the combination of cellular interactions, cytokines and chemokines to induce thymocyte precursors for the generation of functional T cells. The mediators of this process are not well defined but it has been demonstrated that some interactions are under neuroendocrine control. Moreover, some studies pointed out that reciprocal signals from developing T cells also are essential for establishment and maintenance of the thymic microenvironment. Finally, we have also highlighted the heterogeneity of the lymphoid, non-lymphoid components and the multi-phasic steps of thymic differentiation. In conclusion, this review contributes to an understanding of the complex mechanisms in which the foetal and postnatal thymus is involved. This could be a prerequisite for developing new therapies specifically aimed to overcome immunological defects, linked or not-linked to aging.
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74
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Okamoto M, Takeda K, Joetham A, Ohnishi H, Matsuda H, Swasey CH, Swanson BJ, Yasutomo K, Dakhama A, Gelfand EW. Essential role of Notch signaling in effector memory CD8+ T cell-mediated airway hyperresponsiveness and inflammation. ACTA ACUST UNITED AC 2008; 205:1087-97. [PMID: 18426985 PMCID: PMC2373841 DOI: 10.1084/jem.20072200] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Adoptive transfer of in vivo-primed CD8(+) T cells or in vitro-generated effector memory CD8(+) T (T(EFF)) cells restores airway hyperresponsiveness (AHR) and airway inflammation in CD8-deficient (CD8(-/-)) mice. Examining transcription levels, there was a strong induction of Notch1 in T(EFF) cells compared with central memory CD8(+) T cells. Treatment of T(EFF) cells with a gamma-secretase inhibitor (GSI) strongly inhibited Notch signaling in these cells, and after adoptive transfer, GSI-treated T(EFF) cells failed to restore AHR and airway inflammation in sensitized and challenged recipient CD8(-/-) mice, or to enhance these responses in recipient wild-type (WT) mice. These effects of GSI were also associated with increased expression of the Notch ligand Delta1 in T(EFF) cells. Treatment of sensitized and challenged WT mice with Delta1-Fc resulted in decreased AHR and airway inflammation accompanied by higher levels of interferon gamma in bronchoalveolar lavage fluid. These results demonstrate a role for Notch in skewing the T cell response from a T helper (Th)2 to a Th1 phenotype as a consequence of the inhibition of Notch receptor activation and the up-regulation of the Notch ligand Delta1. These data are the first to show a functional role for Notch in the challenge phase of CD8(+) T cell-mediated development of AHR and airway inflammation, and identify Delta1 as an important regulator of allergic airway inflammation.
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Affiliation(s)
- Masakazu Okamoto
- Division of Cell Biology, Department of Pediatrics, National Jewish Medical and Research Center, Denver, CO 80206, USA
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75
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Laky K, Fowlkes BJ. Notch signaling in CD4 and CD8 T cell development. Curr Opin Immunol 2008; 20:197-202. [PMID: 18434124 DOI: 10.1016/j.coi.2008.03.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Accepted: 03/11/2008] [Indexed: 12/16/2022]
Abstract
Because Notch often acts in concert with other signaling pathways, it is able to regulate a diverse set of biological processes in a cell-context dependent manner. In lymphocytes, Notch is essential for specifying the T cell fate and for promoting early stages of T cell differentiation. At later stages of development, Notch signaling is proposed to direct CD4 versus CD8 T lineage commitment. This hypothesis has been challenged by recent studies of conditional Presenilin-deficient mice showing that Notch promotes the selection and maturation of CD4 and CD8 T cells by potentiating TCR signal transduction in immature thymocytes. While similar conclusions have not been reported with conditional mutation of other downstream mediators of Notch activation, it appears that functional inhibition may not have been achieved at a comparable stage of development and/or analogous issues have not been addressed. The differences also question whether in thymocytes Notch signals only through the canonical pathway. Further study of conditional mutants, signaling intermediates, and transcriptional regulators are needed to elucidate how Notch facilitates TCR signaling in generating mature T cells.
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Affiliation(s)
- Karen Laky
- Laboratory of Cellular and Molecular Immunology, NIAID, National Institutes of Health, Bethesda, MD 20892-0420, USA.
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76
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Abstract
Heterodimerization domain (HD) mutations in NOTCH1 induce ligand-independent activation of the receptor and contribute to the pathogenesis of one-third of human T-cell lymphoblastic leukemias (T-ALLs). Here we report a novel class of activating mutations in NOTCH1 leading to aberrant activation of NOTCH1 signaling in T-cell lymphoblasts. These so-called juxtamembrane expansion (JME) alleles consist of internal duplication insertions in the vicinity of exon 28 of the NOTCH1 gene encoding the extracellular juxtamembrane region of the receptor. Notably, structure-function analysis of leukemia-derived and synthetic JME mutants demonstrated that the aberrant activation of NOTCH1 signaling is dependent on the number of residues introduced in the extracellular juxtamembrane region of the receptor and not on the specific amino acid sequence of these insertions. JME NOTCH1 mutants are effectively blocked by gamma-secretase inhibitors and require an intact metalloprotease cleavage site for activation. Overall, these results show a novel mechanism of NOTCH1 activation in T-ALL and provide further insight on the mechanisms that control the activation of NOTCH1 signaling.
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77
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Kamstrup M, Ralfkiaer E, Skovgaard G, Gniadecki R. Potential involvement of Notch1 signalling in the pathogenesis of primary cutaneous CD30-positive lymphoproliferative disorders. Br J Dermatol 2008; 158:747-53. [DOI: 10.1111/j.1365-2133.2007.08427.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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78
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Elyaman W, Bradshaw EM, Wang Y, Oukka M, Kivisäkk P, Chiba S, Yagita H, Khoury SJ. JAGGED1 and delta1 differentially regulate the outcome of experimental autoimmune encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2007; 179:5990-8. [PMID: 17947672 DOI: 10.4049/jimmunol.179.9.5990] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Notch signaling plays an important role during T cell development in the thymus and in T cell activation but the role of Notch in autoimmunity is not clear. We investigated the role of Jagged1 and Delta1 in experimental autoimmune encephalomyelitis. During experimental autoimmune encephalomyelitis, Delta1 expression is up-regulated on dendritic cells and B cells after priming while Jagged1 is up-regulated only on dendritic cells. Administration of anti-Jagged1 Ab exacerbated clinical disease while that of anti-Delta1 Ab reduced the severity of the clinical disease. In contrast, administration of Jagged1-Fc protected from disease, that of Delta1-Fc exacerbated disease. Treatment with Jagged1-Fc was associated with increased IL-10-producing Ag-specific cells in the CNS, while anti-Jagged1 decreased the frequency of IL-10-producing cells. Treatment with Delta1-Fc increased Th1 cells in the CNS, while anti-Delta-1 decreased the frequency of Th1 cells. Manipulation of Delta1 or Jagged1 had no effect on the frequency of Th17 cells or FoxP3(+) cells. Moreover, Jagged1 may play a role in CNS homeostasis because murine astrocytes specifically express Jagged1 that is up-regulated by TGF-beta, whereas IFN-gamma, TNF-alpha, and IL-17 decrease Jagged1 expression. Our study provides novel data about differential roles of Notch ligands in regulating inflammation in the periphery as well as in the CNS.
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Affiliation(s)
- Wassim Elyaman
- Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
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79
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Maraver A, Tadokoro CE, Badura ML, Shen J, Serrano M, Lafaille JJ. Effect of presenilins in the apoptosis of thymocytes and homeostasis of CD8+ T cells. Blood 2007; 110:3218-25. [PMID: 17626841 PMCID: PMC2200904 DOI: 10.1182/blood-2007-01-070359] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Many studies have positioned Notch signaling at various critical junctions during T-cell development. There is, however, debate regarding the role of Notch in the CD4 versus CD8 lineage commitment. Because there are 4 Notch receptors and RBP-Jkappa-independent Notch signaling has been reported, we decided to eliminate gamma-secretase activity once its activity is required for all forms of Notch signaling. T-cell-specific elimination of gamma-secretase was carried out by crossing presenilin-1 (PS1) floxed mice with CD4-Cre mice and PS2 KO mice, generating PS KO mice. Thymic CD4+CD8+ double-positive (DP) cells from these mice were strikingly resistant to apoptosis by anti-CD3 treatment in vivo and expressed more Bcl-X(L) than control thymocytes, and deletion of only one allele of Bcl-X(L) gene restored wild-type levels of sensitivity to apoptosis. In addition, these PS KO animals displayed a significant decrease in the number of CD8+ T cells in the periphery, and these cells had higher level of phosphorylated p38 than cells from control littermates. Our results show that ablation of presenilins results in deficiency of CD8 cells in the periphery and a dramatic change in the physiology of thymocytes, bringing to our attention the potential side effects of presenilin inhibitors in ongoing clinical trials.
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Affiliation(s)
- Antonio Maraver
- Molecular Pathogenesis Program, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, 540 1st Avenue, New York, NY 10016, USA
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80
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Abstract
Like all hematopoietic cells, T lymphocytes are derived from bone-marrow-resident stem cells. However, whereas most blood lineages are generated within the marrow, the majority of T cell development occurs in a specialized organ, the thymus. This distinction underscores the unique capacity of the thymic microenvironment to support T lineage restriction and differentiation. Although the identity of many of the contributing thymus-derived signals is well established and rooted in highly conserved pathways involving Notch, morphogenetic, and protein tyrosine kinase signals, the manner in which the ensuing cascades are integrated to orchestrate the underlying processes of T cell development remains under investigation. This review focuses on the current definition of the early stages of T cell lymphopoiesis, with an emphasis on the nature of thymus-derived signals delivered to T cell progenitors that support the commitment and differentiation of T cells toward the alphabeta and gammadelta T cell lineages.
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Affiliation(s)
- Maria Ciofani
- Molecular Pathogenesis Program, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY 10016, USA.
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81
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Göthert JR, Brake RL, Smeets M, Dührsen U, Begley CG, Izon DJ. NOTCH1 pathway activation is an early hallmark of SCL T leukemogenesis. Blood 2007; 110:3753-62. [PMID: 17698635 DOI: 10.1182/blood-2006-12-063644] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The acquired activation of stem cell leukemia (SCL) during T lymphopoiesis is a common event in T-cell acute lymphoblastic leukemia (T-ALL). Here, we generated tamoxifen (TAM)-inducible transgenic mice (lck-ER(T2)-SCL) to study the consequences of acquired SCL activation during T-cell development. Aberrant activation of SCL in thymocytes resulted in the accumulation of immature CD4(+)CD8(+) (double-positive, DP) cells by preventing normal surface expression of the T-cell receptor alphabeta (TCRalphabeta) complex. SCL-induced immature DP cells were further characterized by up-regulated NOTCH1 and generated noncycling polyclonal CD8(+)TCRbeta(low) cells. The prevalence of these cells was SCL dependent because TAM withdrawal resulted in their disappearance. Furthermore, we observed that SCL activation led to a dramatic up-regulation of NOTCH1 target genes (Hes-1, Deltex1, and CD25) in thymocytes. Strikingly, NOTCH1 target gene up-regulation was already observed after short-term SCL induction, implying that enhanced NOTCH signaling is mediated by SCL and is not dependent on secondary genetic events. These data represent the basis for a novel pathway of SCL-induced leukemogenesis and provide a functional link between SCL and NOTCH1 during this process.
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82
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Abstract
TCRαβ signaling is crucial for the maturation of CD4 and CD8 T cells, but the role of the Notch signaling pathway in this process is poorly understood. Genes encoding Presenilin (PS) 1/2 were deleted to prevent activation of the multiple Notch receptors expressed by developing thymocytes. PS1/2 knockout thymocyte precursors inefficiently generate CD4 T cells, a phenotype that is most pronounced when thymocytes bear a single major histocompatibility complex (MHC) class II–restricted T cell receptor (TCR). Diminished T cell production correlated with evidence of impaired TCR signaling, and could be rescued by manipulations that enhance MHC recognition. Although Notch appears to directly regulate binary fate decisions in many systems, these findings suggest a model in which PS-dependent Notch signaling influences positive selection and the development of αβ T cells by modifying TCR signal transduction.
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Affiliation(s)
- Karen Laky
- Laboratory of Cellular and Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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83
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Baena E, Ortiz M, Martínez-A C, de Alborán IM. c-Myc is essential for hematopoietic stem cell differentiation and regulates Lin(-)Sca-1(+)c-Kit(-) cell generation through p21. Exp Hematol 2007; 35:1333-43. [PMID: 17637497 DOI: 10.1016/j.exphem.2007.05.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2007] [Revised: 05/18/2007] [Accepted: 05/22/2007] [Indexed: 12/26/2022]
Abstract
OBJECTIVE The c-Myc protein is a member of the basic region/helix-loop-helix/leucine zipper (bHLHZip) transcription factor family, which is implicated in regulation of proliferation, differentiation, and apoptosis in multiple cell types. The aim of this study was to characterize the role of the proto-oncogene c-myc in hematopoietic stem cells (HSC) during postnatal development. MATERIAL AND METHODS We have generated a conditional mouse model that allows us to inactivate c-myc in bone marrow (BM) in an inducible fashion. RESULTS We show that conditional inactivation of c-Myc in BM severely impairs HSC differentiation, leading to a striking decrease in the number of lymphoid and myeloid cells. c-Myc deletion in BM causes substantial accumulation of a Lin(-)Sca-1(+)c-Kit(-) cell population expressing high levels of the cell-cycle inhibitor p21, whose origin and function are otherwise poorly characterized. In vivo inactivation of p21 and c-Myc normalizes Lin(-)Sca-1(+)c-Kit(-) cell numbers and restores normal proliferation. The potential origin and function of these cells are discussed. CONCLUSIONS c-Myc plays a role in HSC maintenance and differentiation and might be regulating generation of Lin(-)Sca-1(+)c-Kit(-) through the cell-cycle regulator p21.
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Affiliation(s)
- Esther Baena
- Department of Immunology and Oncology, Centro Nacional de Biotecnología/CSIC, Universidad Autónoma de Madrid, Madrid, Spain
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84
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Shimizu D, Taki T, Utsunomiya A, Nakagawa H, Nomura K, Matsumoto Y, Nishida K, Horiike S, Taniwaki M. Detection of NOTCH1 mutations in adult T-cell leukemia/lymphoma and peripheral T-cell lymphoma. Int J Hematol 2007; 85:212-8. [PMID: 17483057 DOI: 10.1532/ijh97.06165] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We analyzed NOTCH1 gene mutation in 53 adults with mature T-cell leukemia/lymphoma: 21 patients with adult T-cell leukemia (ATL), 25 with T-cell non-Hodgkin's lymphoma (T-NHL), and 7 with T-cell prolymphocytic leukemia. We detected a nonsense mutation, C7249T (resulting in Q2417X, where X is a termination codon) in the PEST domain of NOTCH1 in an ATL patient and detected a 3-bp deletion (positions 7234-7236) that resulted in deletion of a proline codon at codon 2412 in the PEST domain of NOTCH1 in a patient with a T-NHL, peripheral T-cell lymphoma-unspecified (PTCL-u). We also analyzed the expression of NOTCH1 target genes (HES1, CCND1, and MYC), all of which were expressed in the sample of the PTCL-u patient with the NOTCH1 mutation, but found only MYC to be expressed in the sample from the ATL patient. These findings suggest that nonsense mutation in the PEST domain in the ATL case was associated with NOTCH1 signaling through a pathway different from that for T-cell acute lymphoblastic leukemia (T-ALL). Although NOTCH1 mutation occurs infrequently in mature T-cell leukemia/lymphoma, NOTCH1 may be involved in leukemogenesis associated with various forms of T-cell leukemia/lymphoma rather than only with T-ALL.
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Affiliation(s)
- Daisuke Shimizu
- Department of Molecular Hematology and Oncology, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan
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85
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Petrie HT, Zúñiga-Pflücker JC. Zoned out: functional mapping of stromal signaling microenvironments in the thymus. Annu Rev Immunol 2007; 25:649-79. [PMID: 17291187 DOI: 10.1146/annurev.immunol.23.021704.115715] [Citation(s) in RCA: 339] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
All hematopoietic cells, including T lymphocytes, originate from stem cells that reside in the bone marrow. Most hematopoietic lineages also mature in the bone marrow, but in this respect, T lymphocytes differ. Under normal circumstances, most T lymphocytes are produced in the thymus from marrow-derived progenitors that circulate in the blood. Cells that home to the thymus from the marrow possess the potential to generate multiple T and non-T lineages. However, there is little evidence to suggest that, once inside the thymus, they give rise to anything other than T cells. Thus, signals unique to the thymic microenvironment compel multipotent progenitors to commit to the T lineage, at the expense of other potential lineages. Summarizing what is known about the signals the thymus delivers to uncommitted progenitors, or to immature T-committed progenitors, to produce functional T cells is the focus of this review.
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Affiliation(s)
- Howard T Petrie
- Scripps Florida Research Institute, Jupiter, Florida 33458, USA.
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86
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Lee KY, Choi YI, Kim J, Choi JW, Sohn DH, Lee C, Jeon SH, Seong RH. Down-Regulation of the SWI/SNF Chromatin Remodeling Activity by TCR Signaling Is Required for Proper Thymocyte Maturation. THE JOURNAL OF IMMUNOLOGY 2007; 178:7088-96. [PMID: 17513758 DOI: 10.4049/jimmunol.178.11.7088] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The process of thymocyte development requires an exquisite regulation of many genes via transcription factors and chromatin remodeling activities. Even though the SWI/SNF chromatin remodeling complex has been thought to play important roles during thymocyte development, its known function is very limited. In this study, we show that the SWI/SNF chromatin remodeling activity is finely regulated during thymocyte maturation process, especially during thymocyte selections. We found that TCR signaling directly down-regulates mBRG1 and SWI3-related gene, the core components of murine SWI/SNF complex, during thymocyte maturation. Constitutive expression of SWI3-related gene in developing thymocytes attenuated the down-regulation of the SWI/SNF complex and resulted in a change in the expression of genes such as linker for activation of T cells and casitas B lineage lymphoma, which affected the TCR-mediated intracellular signaling pathway. The defects in TCR signaling resulted in the disruption of both positive and negative selections in specific TCR transgenic mice systems. Our results state, for the first time, that the chromatin remodeling activity needs to be finely controlled for proper thymocyte selection and maturation processes.
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MESH Headings
- Animals
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Cells, Cultured
- Chromatin/genetics
- Chromatin/metabolism
- Chromosomal Proteins, Non-Histone/antagonists & inhibitors
- Chromosomal Proteins, Non-Histone/physiology
- Down-Regulation/genetics
- Down-Regulation/immunology
- Female
- Growth Inhibitors/antagonists & inhibitors
- Growth Inhibitors/biosynthesis
- Growth Inhibitors/genetics
- Male
- Mice
- Mice, Inbred A
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Receptors, Antigen, T-Cell/antagonists & inhibitors
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/physiology
- Repressor Proteins/antagonists & inhibitors
- Repressor Proteins/biosynthesis
- Repressor Proteins/genetics
- Signal Transduction/genetics
- Signal Transduction/immunology
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- Thymus Gland/cytology
- Thymus Gland/immunology
- Thymus Gland/metabolism
- Trans-Activators/antagonists & inhibitors
- Trans-Activators/biosynthesis
- Trans-Activators/genetics
- Transcription Factors/antagonists & inhibitors
- Transcription Factors/physiology
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Affiliation(s)
- Kyoo Y Lee
- Department of Biological Sciences, Institute of Molecular Biology and Genetics, and Research Center for Functional Cellulomics, Seoul National University, Seoul, Korea
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87
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Nakamura S, Suzuki M, Sugimoto A, Tsuji-Takayama K, Yamamoto M, Otani T, Inoue T, Harashima A, Okochi A, Motoda R, Yamasaki F, Orita K, Kibata M. IL-2-independent generation of FOXP3+CD4+CD8+CD25+ cytotoxic regulatory T cell lines from human umbilical cord blood. Exp Hematol 2007; 35:287-96. [PMID: 17258077 DOI: 10.1016/j.exphem.2006.10.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 09/20/2006] [Accepted: 10/17/2006] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Since the existence of mouse naturally occurring CD4(+)CD25(+) T regulatory (Treg) cells was demonstrated, a variety of human Treg subsets have been identified as distinct T cell populations. Here we show the establishment of novel Treg cell lines possessing unique characteristics. METHODS Novel Treg cell lines, designated HOZOT, were generated by coculturing human umbilical cord blood cells with mouse stromal cell lines in the absence of exogenous IL-2 or other cytokines. HOZOT were characterized and compared with CD4(+)CD25(+) Treg cells in terms of the CD phenotype, FOXP3 expression, suppressor activity against allogeneic MLR, anergy property, and IL-10 production. RESULTS HOZOT were generated and expanded as normal lymphoblastoid cells with cytotoxic activity against the cocultured stromal cells. HOZOT consisted of three subpopulations as defined by phenotype: CD4(+)CD8(+), CD4(+)CD8(dim), and CD4(-)CD8(+). All three subpopulations showed both suppressor and cytotoxic activities. While HOZOT's expression of FOXP3, CD25, GITR, and cytoplasmic CTLA-4 implied a similarity to naturally occurring CD4(+)CD25(+) Treg cells, these two Treg cells differed in IL-2 responsiveness and IL-10 production. CONCLUSIONS Our studies introduce a new method of generating Treg cells in an IL-2-independent manner and highlight a unique Treg cell type with cytotoxic activity and a phenotype of FOXP3(+)CD4(+)CD8(+)CD25(+).
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Affiliation(s)
- Shuji Nakamura
- Cell Biology Institute, Research Center, Hayashibara Biochemical Laboratories, Inc., Okayama, Okayama, Japan.
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88
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Osborne BA, Minter LM. Notch signalling during peripheral T-cell activation and differentiation. Nat Rev Immunol 2006; 7:64-75. [PMID: 17170755 DOI: 10.1038/nri1998] [Citation(s) in RCA: 177] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
For many years, researchers have focused on the contribution of Notch signalling to lymphoid development. Only recently have investigators begun to ask what role, if any, Notch has during the activation and differentiation of naive CD4(+) T cells in the periphery. As interest in this issue grows, it is becoming increasingly clear that the main role of Notch signalling, to regulate cell-fate decisions, might also be influential in peripheral T cells.
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Affiliation(s)
- Barbara A Osborne
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Massachusetts 01003, USA.
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89
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Takahashi K, Akiyama H, Shimazaki K, Uchida C, Akiyama-Okunuki H, Tomita M, Fukumoto M, Uchida T. Ablation of a peptidyl prolyl isomerase Pin1 from p53-null mice accelerated thymic hyperplasia by increasing the level of the intracellular form of Notch1. Oncogene 2006; 26:3835-45. [PMID: 17160015 DOI: 10.1038/sj.onc.1210153] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tumor suppressor p53 is essential for checkpoint control in response to a variety of genotoxic stresses. DNA damage leads to phosphorylation on the Ser/Thr-Pro motifs of p53, which facilitates interaction with Pin1, a pSer/pThr-Pro-specific peptidyl prolyl isomerase. Pin1 is required for the timely activation of p53, resulting in apoptosis or cell cycle arrest. To investigate the physiological relationship between Pin1 and p53, we created Pin1-/-p53-/- mice. These p53-deficient mice spontaneously developed lymphomas, mainly of thymic origin, as well as generalized lymphoma infiltration into other organs, including the liver, kidneys and lungs. Ablation of Pin1, in addition to p53, accelerated the thymic hyperplasia, but the thymocytes in these Pin1-/-p53-/- mice did not infiltrate other organs. The thymocytes in 12-week-old Pin1-/-p53-/- mice were CD4(-)CD8(-) (double negative) and had significantly higher levels of the intracellular form of Notch1 (NIC) than the thymocytes of p53-/- or wild-type mice. Presenilin-1, a cleavage enzyme for NIC generation from full-length Notch1 was increased in the thymocytes of Pin1-/-p53-/- mice. Pin1 depletion also inhibited the degradation of NIC by proteasomes. These results suggest that both Pin1 and p53 control the normal proliferation and differentiation of thymocytes by regulating the NIC level.
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Affiliation(s)
- K Takahashi
- Center for Interdisciplinary Research, Tohoku University, Sendai, Miyagi, Japan
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90
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Radtke F, Wilson A, MacDonald HR. Notch signaling in hematopoiesis and lymphopoiesis: lessons from Drosophila. Bioessays 2006; 27:1117-28. [PMID: 16237675 DOI: 10.1002/bies.20315] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The evolutionarily conserved Notch signaling pathway regulates a broad spectrum of cell fate decisions and differentiation processes during fetal and postnatal life. It is involved in embryonic organogenesis as well as in the maintenance of homeostasis of self-renewing systems. In this article, we review the role of Notch signaling in the hematopoietic system with particular emphasis on lymphocyte development and highlight the similarities in Notch function between Drosophila and mammalian differentiation processes. Recent studies indicating that aberrant NOTCH signaling is frequently linked to the induction of T leukemia in humans will also be discussed.
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Affiliation(s)
- Freddy Radtke
- Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Epalinges, Switzerland.
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91
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Matesic LE, Haines DC, Copeland NG, Jenkins NA. Itch genetically interacts with Notch1 in a mouse autoimmune disease model. Hum Mol Genet 2006; 15:3485-97. [PMID: 17095521 DOI: 10.1093/hmg/ddl425] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Homozygous itchy mice develop a fatal, late-onset autoimmune-like disease due to a loss of function mutation in an ubiquitin protein ligase. Phylogenetic and in vitro analyses suggest that Itch is a negative regulator of Notch signaling. Since Notch proteins have many important functions in the immune system, we determined whether Itch regulates Notch signaling in vivo. This was accomplished by breeding homozygous itch mice to mice carrying an activated Notch1 transgene that was specifically overexpressed in developing thymocytes. Interestingly, all itch mice carrying this transgene were smaller than their littermates and died by 12 weeks of age. These mice had a similar autoimmune disease to that seen in itch animals. However, the lesions were more severe with a much earlier age of onset, supporting the assertion that these mutations genetically interact. In addition, the combination of these mutations produced novel phenotypes including a perturbation in T cell development, with a reduction in the number of double-positive (DP) and an increase in the number of double-negative and single-positive T cells. TUNEL staining showed reduced apoptosis in the thymus of itch animals that carry the Notch1 transgene. Antibody staining displayed increased levels of full-length Notch1 and phospho-AKT specifically in DP thymocytes but no change in other signaling pathways including MAPK, p38 and JNK. These results provide the first direct demonstration that increased AKT-mediated Notch1 signaling results in autoimmunity and may provide insight into the treatment of a group of diseases that affect a significant proportion of the population.
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Affiliation(s)
- Lydia E Matesic
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA.
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92
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Pongracz JE, Parnell SM, Jones T, Anderson G, Jenkinson EJ. Overexpression of ICAT highlights a role for catenin-mediated canonical Wnt signalling in early T cell development. Eur J Immunol 2006; 36:2376-83. [PMID: 16897815 DOI: 10.1002/eji.200535721] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Transcription factors of the T cell factor/lymphoid enhancing factor (Tcf/Lef) family are key regulators in the development of T cell precursors to the CD4+8+ stage. These factors are known targets of the canonical Wnt signalling pathway, and regulate transcription of Wnt target genes following interaction with the armadillo repeat-containing protein beta-catenin. However, as recent studies show normal thymocyte maturation in the absence of either beta-catenin or its homologue gamma-catenin, the role of Wnt signalling in Tcf/Lef activation during T cell development is controversial. To directly investigate the importance of catenin-mediated Wnt signalling in early thymocytes, we have compared the expression of beta- and gamma-catenin and analysed distinct stages of T cell precursor maturation following overexpression of inhibitor of beta-catenin and Tcf (ICAT), which inhibits Wnt signalling by preventing binding of armadillo repeat-containing proteins to Tcf/Lef. By direct retroviral gene targeting of CD4-8- and CD4+8+ precursors, we show that ICAT overexpression inhibits the CD4-8--to-CD4+8+ transition, but not the CD4+8+-to-CD4+8- or -CD4-8+ transition. Collectively, our data support a model in which canonical Wnt signalling influences T cell development in the thymus by playing an essential role in the maturation of CD4-8- but not CD4+8+ thymocytes.
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Affiliation(s)
- Judit E Pongracz
- MRC Centre for Immune Regulation, Division of Immunity and Infection, Institute for Biomedical Research, University of Birmingham, Birmingham, UK
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93
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Priceputu E, Bouallaga I, Zhang Y, Li X, Chrobak P, Hanna ZS, Poudrier J, Kay DG, Jolicoeur P. Structurally distinct ligand-binding or ligand-independent Notch1 mutants are leukemogenic but affect thymocyte development, apoptosis, and metastasis differently. THE JOURNAL OF IMMUNOLOGY 2006; 177:2153-66. [PMID: 16887975 DOI: 10.4049/jimmunol.177.4.2153] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We previously found that provirus insertion in T cell tumors of mouse mammary tumor virus/c-myc transgenic (Tg) mice induced two forms of Notch1 mutations. Type I mutations generated two truncated molecules, one intracellular (IC) (Notch1(IC)) and one extracellular (Notch1(EC)), while in type II mutations Notch1 was deleted of its C terminus (Notch1(DeltaCT)). We expressed these mutants in Tg mice using the CD4 promoter. Both Notch1(IC) and Notch1(DeltaCT), but not Notch1(EC), Tg mice developed double-positive (DP) thymomas. These disseminated more frequently in Notch1(DeltaCT) Tg mice. Double (Notch1(IC) x myc) or (Notch1(DeltaCT) x myc) Tg mice developed thymoma with a much shorter latency than single Tg mice, providing genetic evidence of a collaboration between these two oncogenes. FACS analysis of preleukemic thymocytes did not reveal major T cell differentiation anomalies, except for a higher number of DP cells and an accumulation of TCR(high)CD2(high)CD25(high) DP cells in Notch1(IC), and less so in Notch1(DeltaCT) Tg mice. This was associated with enhanced in vivo thymocyte proliferation. However, Notch1(IC), but not Notch1(DeltaCT), DP thymocytes were protected against apoptosis induced in vivo by dexamethasone and anti-CD3 and in vitro by anti-CD3/CD28 Abs. This indicates that the C terminus of Notch1 and/or the conserved regulation by its ligands have a significant impact on the induced T cell phenotype. Therefore, Notch1(IC) and Notch1(DeltaCT) behave as oncogenes for T cells. Because these two Notch1 mutations are very similar to those described in some forms of human T cell leukemia, these Tg mice may represent relevant models of these human leukemias.
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MESH Headings
- Animals
- Apoptosis/genetics
- Apoptosis/immunology
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Disease Models, Animal
- Gene Deletion
- Leukemia-Lymphoma, Adult T-Cell/genetics
- Leukemia-Lymphoma, Adult T-Cell/immunology
- Leukemia-Lymphoma, Adult T-Cell/pathology
- Ligands
- Lymphatic Metastasis
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Nude
- Mice, Transgenic
- Preleukemia/genetics
- Preleukemia/immunology
- Preleukemia/pathology
- Protein Binding/immunology
- Proto-Oncogene Proteins c-myc/biosynthesis
- Proto-Oncogene Proteins c-myc/genetics
- Receptor, Notch1/biosynthesis
- Receptor, Notch1/chemistry
- Receptor, Notch1/genetics
- Receptor, Notch1/metabolism
- Thymoma/genetics
- Thymoma/immunology
- Thymoma/pathology
- Thymoma/secondary
- Thymus Gland/immunology
- Thymus Gland/pathology
- Thymus Neoplasms/genetics
- Thymus Neoplasms/immunology
- Thymus Neoplasms/pathology
- Thymus Neoplasms/secondary
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Affiliation(s)
- Elena Priceputu
- Laboratory of Molecular Biology, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montréal, Québec, Canada
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94
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Anderson G, Jenkinson WE, Jones T, Parnell SM, Kinsella FAM, White AJ, Pongrac'z JE, Rossi SW, Jenkinson EJ. Establishment and functioning of intrathymic microenvironments. Immunol Rev 2006; 209:10-27. [PMID: 16448531 DOI: 10.1111/j.0105-2896.2006.00347.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The thymus supports the production of self-tolerant T cells from immature precursors. Studying the mechanisms regulating the establishment and maintenance of stromal microenvironments within the thymus therefore is essential to our understanding of T-cell production and ultimately immune system functioning. Despite our ability to phenotypically define stromal cell compartments of the thymus, the mechanisms regulating their development and the ways by which they influence T-cell precursors are still unclear. Here, we review recent findings and highlight unresolved issues relating to the development and functioning of thymic stromal cells.
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Affiliation(s)
- Graham Anderson
- MRC Center for Immune Regulation, Division of Immunity and Infection, Institute For Biomedical Research, Medical School, University of Birmingham, Edgbaston, Birmingham, UK.
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95
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Visan I, Yuan JS, Tan JB, Cretegny K, Guidos CJ. Regulation of intrathymic T-cell development by Lunatic Fringe- Notch1 interactions. Immunol Rev 2006; 209:76-94. [PMID: 16448535 DOI: 10.1111/j.0105-2896.2006.00360.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Intrathymic Notch1 signaling critically regulates T-lineage specification and commitment as well as T-cell progenitor survival and differentiation. Notch1 activation is continuously required during progression of early CD4/CD8-double-negative thymocytes to the CD4/CD8-double-positive stage. This developmental transition occurs as thymocytes migrate from the corticomedullary junction (CMJ) to the outer subcapsular zone (SCZ) of the thymus. Members of two families of structurally distinct Notch ligands, Delta-like 1 and Jagged-1, are expressed by cortical thymic epithelial cells, but it is not known which ligands are functionally required within the CMJ and SCZ microenvironmental niches. Our laboratory has investigated this question by genetically manipulating thymocyte expression of Lunatic Fringe (L-Fng), a glycosyltransferase that enhances sensitivity of Notch receptors to Delta-like ligands. This approach has revealed that low-threshold intrathymic Notch1 signals instruct multipotent thymus-seeding progenitors to suppress their B-cell potential and choose the T-cell fate. This strategy has also revealed that Delta-like Notch ligands are functionally limiting in both the CMJ and SCZ microenvironmental niches. Finally, we discuss our recent demonstration that L-Fng-mediated competition for Delta-like ligands is an important mechanism for regulating thymus size.
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Affiliation(s)
- Ioana Visan
- Program in Developmental Biology, Hospital for Sick Children Research Institute, and Department of Immunology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
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96
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Abstract
The generation of CD4 and CD8 alphabeta T-cell lineages from CD4+ CD8+ double-positive (DP) thymocyte precursors is a complex process initiated by engagement of major histocompatibility complex (MHC) by T-cell receptor (TCR) and coreceptor. Quantitative differences in TCR signaling induced by this interaction impose an instructional bias on CD4/CD8 lineage commitment that must be reinforced by MHC recognition and TCR signaling over subsequent selection steps in order for the thymocyte to progress and mature in the adopted lineage. Our studies show that the transmembrane receptor Notch plays a role in this process by modifying TCR signal transduction in DP thymocytes. In this review, we consider the functional relationship of TCR and Notch signaling pathways in the selection and specification of CD4 and CD8 T-cell lineages.
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Affiliation(s)
- Karen Laky
- Laboratory of Cellular and Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-0420, USA
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97
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van den Brandt J, Kwon SH, McPherson KG, Petrovic S, Zettl A, Müller-Hermelink HK, Reichardt HM. Unexpected features of acute T lymphoblastic lymphomas in Notch1IC transgenic rats. Eur J Immunol 2006; 36:2223-34. [PMID: 16838279 DOI: 10.1002/eji.200535791] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Dysregulated Notch signaling accounts for the majority of acute T lymphoblastic leukemia/lymphoma (T-ALL) cases in humans. Here, we characterize lymphomas from Notch1IC transgenic rats, which develop T-ALL shortly after weaning, and show that they display a number of previously undocumented features. Starting from monoclonal thymic tumors, the CD4(+)CD8alphaalpha(+) lymphoma cells infiltrate the bone marrow and then spread to secondary lymphoid and non-lymphoid organs. However, major hallmarks of T-ALL cells in other murine models and human patients, such as constitutive NF-kappaB activity and increased levels of anti-apoptotic proteins, are remarkably absent in Notch1IC lymphomas. In contrast, CD30, a classic marker of Hodgkin lymphomas, is overexpressed in these tumors. Intriguingly, enforced Notch1 signaling up-regulates expression of Notch3, which has also been implicated in the pathogenesis of T-ALL. By blocking endogenous Notch signaling, we could demonstrate that Notch1IC is sufficient to induce sustained preTCR expression in transgenic thymocytes but not for their progression to the double-positive stage. This suggests that other Notch activities may also contribute to the phenotype of the transgenic rats. In summary, we anticipate this new animal model will help to further elucidate the role of Notch1 in the pathogenesis of T-ALL.
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Affiliation(s)
- Jens van den Brandt
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
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98
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Tachikawa Y, Matsushima T, Abe Y, Sakano S, Yamamoto M, Nishimura J, Nawata H, Takayanagi R, Muta K. Pivotal role of Notch signaling in regulation of erythroid maturation and proliferation. Eur J Haematol 2006; 77:273-81. [PMID: 16930143 DOI: 10.1111/j.0902-4441.2006.t0-1-ejh2708.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Notch signaling plays an important role in cell fate decisions in developmental systems. To clarify its role in committed hematopoietic progenitor cells, we investigated the effects of Notch signaling in erythroid colony forming cells (ECFCs) generated from peripheral blood. ECFCs express Notch receptors, Notch1 and Notch2, and Notch ligands Delta1, Delta4, and Jagged1. When we assayed the effects of Notch ligands on erythroid maturation by flow cytometry, we found that immobilized Delta1 and immobilized Delta4 in particular inhibited maturation, whereas Jagged1 had no effect. In addition, Delta4 inhibited proliferation without reducing cell viability. Increases in expression levels of the Notch target gene hairy enhancer of split (HES) -1 were evident by real-time PCR after stimulation with immobilized Delta4. The effect of soluble Delta4 on expression of HES-1 was less pronounced than that seen with the immobilized form, indicating that all surface-bound ligands are important for effective signal transduction. When ECFCs were cultured in the presence of soluble Delta4 at a low cell concentration, erythroid maturation was slightly inhibited, but at a high concentration, maturation was promoted via competition of soluble Delta4 with endogenous ligands. These results indicate a pivotal role of Notch signaling in regulating erythroid maturation and proliferation, and further suggest that cell-cell interactions modulate growth of erythroid progenitor cells via Notch system.
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Affiliation(s)
- Yoshimichi Tachikawa
- Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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99
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Beverly LJ, Ascano JM, Capobianco AJ. Expression of JAGGED1 in T-lymphocytes results in thymic involution by inducing apoptosis of thymic stromal epithelial cells. Genes Immun 2006; 7:476-86. [PMID: 16791277 DOI: 10.1038/sj.gene.6364318] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Proper development of the thymus and differentiation of T-lymphocytes requires cell-cell interactions between the developing T-lymphocytes and the thymic epithelia. The Delta/Serrate/Lag-2 (DSL)/Notch signal-transduction pathway is known to govern cell fate decisions required for proper development through direct cell-cell interactions. The functional consequences of specific DSL/Notch interactions during the development of a complex organ, such as the thymus, have not been thoroughly elucidated, however. In order to examine the role of DSL proteins during thymus development and T-lymphocyte differentiation, we targeted expression of JAGGED1 in T-lymphocyte progenitors via the control of the proximal lck promoter. Here, we report that expression of JAGGED1 in T cells causes premature involution of the thymus by directing thymic epithelial cells to undergo an apoptotic program. Adoptive transfer of JAGGED1 transgenic bone marrow into non-transgenic mice revealed that JAGGED1 expression on T cells does not alter T-cell differentiation, but is directly responsible for involution of the thymus. We propose that the phenotype of the lck-JAGGED1 transgenic mice is a direct result of specific DSL/Notch interactions and improper cell-to-cell signaling.
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Affiliation(s)
- L J Beverly
- The Wistar Institute, Philadelphia, PA 19104, USA
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100
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Yang X, Tomita T, Wines-Samuelson M, Beglopoulos V, Tansey MG, Kopan R, Shen J. Notch1 signaling influences v2 interneuron and motor neuron development in the spinal cord. Dev Neurosci 2006; 28:102-17. [PMID: 16508308 DOI: 10.1159/000090757] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2005] [Accepted: 06/21/2005] [Indexed: 12/21/2022] Open
Abstract
The Notch signaling pathway plays a variety of roles in cell fate decisions during development. Previous studies have shown that reduced Notch signaling results in premature differentiation of neural progenitor cells, while increased Notch activities promote apoptotic death of neural progenitor cells in the developing brain. Whether Notch signaling is involved in the specification of neuronal subtypes is unclear. Here we examine the role of Notch1 in the development of neuronal subtypes in the spinal cord using conditional knockout (cKO) mice lacking Notch1 specifically in neural progenitor cells. Notch1 inactivation results in accelerated neuronal differentiation in the ventral spinal cord and gradual disappearance of the ventral central canal. These changes are accompanied by reduced expression of Hes1 and Hes5 and increased expression of Mash1 and Neurogenin 1 and 2. Using markers (Nkx2.2, Nkx6.1, Olig2, Pax6 and Dbx1) for one or multiple progenitor cell types, we found reductions of all subtypes of progenitor cells in the ventral spinal cord of Notch1 cKO mice. Similarly, using markers (Islet1/2, Lim3, Sim1, Chox10, En1 and Evx1/2) specific for motor neurons and distinct classes of interneurons, we found increases in the number of V0-2 interneurons in the ventral spinal cord of Notch1 cKO mice. Specifically, the number of Lim3+/Chox10+ V2 interneurons is markedly increased while the number of Lim3+/Islet+motor neurons is decreased in the Notch1 cKO spinal cord, suggesting that V2 interneurons are generated at the expense of motor neurons in the absence of Notch1. These results provide support for a role of Notch1 in neuronal subtype specification in the ventral spinal cord.
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Affiliation(s)
- Xudong Yang
- Center for Neurologic Diseases, Brigham and Women's Hospital, Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA
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