1
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Gui Y, Cheng H, Zhou J, Xu H, Han J, Zhang D. Development and function of natural TCR + CD8αα + intraepithelial lymphocytes. Front Immunol 2022; 13:1059042. [PMID: 36569835 PMCID: PMC9768216 DOI: 10.3389/fimmu.2022.1059042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/24/2022] [Indexed: 12/12/2022] Open
Abstract
The complexity of intestinal homeostasis results from the ability of the intestinal epithelium to absorb nutrients, harbor multiple external and internal antigens, and accommodate diverse immune cells. Intestinal intraepithelial lymphocytes (IELs) are a unique cell population embedded within the intestinal epithelial layer, contributing to the formation of the mucosal epithelial barrier and serving as a first-line defense against microbial invasion. TCRαβ+ CD4- CD8αα+ CD8αβ- and TCRγδ+ CD4- CD8αα+ CD8αβ- IELs are the two predominant subsets of natural IELs. These cells play an essential role in various intestinal diseases, such as infections and inflammatory diseases, and act as immune regulators in the gut. However, their developmental and functional patterns are extremely distinct, and the mechanisms underlying their development and migration to the intestine are not fully understood. One example is that Bcl-2 promotes the survival of thymic precursors of IELs. Mature TCRαβ+ CD4- CD8αα+ CD8αβ- IELs seem to be involved in immune regulation, while TCRγδ+ CD4- CD8αα+ CD8αβ- IELs might be involved in immune surveillance by promoting homeostasis of host microbiota, protecting and restoring the integrity of mucosal epithelium, inhibiting microbiota invasion, and limiting excessive inflammation. In this review, we elucidated and organized effectively the functions and development of these cells to guide future studies in this field. We also discussed key scientific questions that need to be addressed in this area.
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Affiliation(s)
- Yuanyuan Gui
- Department of Biotherapy, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Hao Cheng
- Department of Biotherapy, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Jingyang Zhou
- Department of Biotherapy, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Hao Xu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jiajia Han
- Precision Research Center for Refractory Diseases, Institute for Clinical Research, Shanghai General Hospital, Shanghai Jiao Tong University of Medicine, Shanghai, China,*Correspondence: Jiajia Han, ; Dunfang Zhang,
| | - Dunfang Zhang
- Department of Biotherapy, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, China,*Correspondence: Jiajia Han, ; Dunfang Zhang,
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2
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Kissiov DU, Ethell A, Chen S, Wolf NK, Zhang C, Dang SM, Jo Y, Madsen KN, Paranjpe I, Lee AY, Chim B, Muljo SA, Raulet DH. Binary outcomes of enhancer activity underlie stable random monoallelic expression. eLife 2022; 11:e74204. [PMID: 35617021 PMCID: PMC9135403 DOI: 10.7554/elife.74204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 03/21/2022] [Indexed: 11/21/2022] Open
Abstract
Mitotically stable random monoallelic gene expression (RME) is documented for a small percentage of autosomal genes. We developed an in vivo genetic model to study the role of enhancers in RME using high-resolution single-cell analysis of natural killer (NK) cell receptor gene expression and enhancer deletions in the mouse germline. Enhancers of the RME NK receptor genes were accessible and enriched in H3K27ac on silent and active alleles alike in cells sorted according to allelic expression status, suggesting enhancer activation and gene expression status can be decoupled. In genes with multiple enhancers, enhancer deletion reduced gene expression frequency, in one instance converting the universally expressed gene encoding NKG2D into an RME gene, recapitulating all aspects of natural RME including mitotic stability of both the active and silent states. The results support the binary model of enhancer action, and suggest that RME is a consequence of general properties of gene regulation by enhancers rather than an RME-specific epigenetic program. Therefore, many and perhaps all genes may be subject to some degree of RME. Surprisingly, this was borne out by analysis of several genes that define different major hematopoietic lineages, that were previously thought to be universally expressed within those lineages: the genes encoding NKG2D, CD45, CD8α, and Thy-1. We propose that intrinsically probabilistic gene allele regulation is a general property of enhancer-controlled gene expression, with previously documented RME representing an extreme on a broad continuum.
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Affiliation(s)
- Djem U Kissiov
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Alexander Ethell
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Sean Chen
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Natalie K Wolf
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Chenyu Zhang
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Susanna M Dang
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Yeara Jo
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Katrine N Madsen
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Ishan Paranjpe
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Angus Y Lee
- Cancer Research Laboratory, University of California, BerkeleyBerkeleyUnited States
| | - Bryan Chim
- Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of HealthBethesdaUnited States
| | - Stefan A Muljo
- Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of HealthBethesdaUnited States
| | - David H Raulet
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
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3
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Chu JM, Pease NA, Kueh HY. In search of lost time: Enhancers as modulators of timing in lymphocyte development and differentiation. Immunol Rev 2021; 300:134-151. [PMID: 33734444 PMCID: PMC8005465 DOI: 10.1111/imr.12946] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/15/2020] [Accepted: 12/23/2020] [Indexed: 12/21/2022]
Abstract
Proper timing of gene expression is central to lymphocyte development and differentiation. Lymphocytes often delay gene activation for hours to days after the onset of signaling components, which act on the order of seconds to minutes. Such delays play a prominent role during the intricate choreography of developmental events and during the execution of an effector response. Though a number of mechanisms are sufficient to explain timing at short timescales, it is not known how timing delays are implemented over long timescales that may span several cell generations. Based on the literature, we propose that a class of cis-regulatory elements, termed "timing enhancers," may explain how timing delays are controlled over these long timescales. By considering chromatin as a kinetic barrier to state switching, the timing enhancer model explains experimentally observed dynamics of gene expression where other models fall short. In this review, we elaborate on features of the timing enhancer model and discuss the evidence for its generality throughout development and differentiation. We then discuss potential molecular mechanisms underlying timing enhancer function. Finally, we explore recent evidence drawing connections between timing enhancers and genetic risk for immunopathology. We argue that the timing enhancer model is a useful framework for understanding how cis-regulatory elements control the central dimension of timing in lymphocyte biology.
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Affiliation(s)
- Jonathan M Chu
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, Seattle, WA, USA
| | - Nicholas A Pease
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, Seattle, WA, USA
| | - Hao Yuan Kueh
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, Seattle, WA, USA
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4
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Li Y, Osuma A, Correa E, Okebalama MA, Dao P, Gaylord O, Aburas J, Islam P, Brown AE, Kratsios P. Establishment and maintenance of motor neuron identity via temporal modularity in terminal selector function. eLife 2020; 9:59464. [PMID: 33001031 PMCID: PMC7529460 DOI: 10.7554/elife.59464] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 09/20/2020] [Indexed: 02/06/2023] Open
Abstract
Terminal selectors are transcription factors (TFs) that establish during development and maintain throughout life post-mitotic neuronal identity. We previously showed that UNC-3/Ebf, the terminal selector of C. elegans cholinergic motor neurons (MNs), acts indirectly to prevent alternative neuronal identities (Feng et al., 2020). Here, we globally identify the direct targets of UNC-3. Unexpectedly, we find that the suite of UNC-3 targets in MNs is modified across different life stages, revealing ‘temporal modularity’ in terminal selector function. In all larval and adult stages examined, UNC-3 is required for continuous expression of various protein classes (e.g. receptors, transporters) critical for MN function. However, only in late larvae and adults, UNC-3 is required to maintain expression of MN-specific TFs. Minimal disruption of UNC-3’s temporal modularity via genome engineering affects locomotion. Another C. elegans terminal selector (UNC-30/Pitx) also exhibits temporal modularity, supporting the potential generality of this mechanism for the control of neuronal identity.
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Affiliation(s)
- Yinan Li
- Department of Neurobiology, University of Chicago, Chicago, United States.,Committee on Neurobiology, University of Chicago, Chicago, United States
| | - Anthony Osuma
- Department of Neurobiology, University of Chicago, Chicago, United States.,Committee on Neurobiology, University of Chicago, Chicago, United States
| | - Edgar Correa
- Department of Neurobiology, University of Chicago, Chicago, United States.,Cell and Molecular Biology Program, University of Chicago, Chicago, United States
| | | | - Pauline Dao
- Department of Neurobiology, University of Chicago, Chicago, United States
| | - Olivia Gaylord
- Committee on Development, Regeneration and Stem Cell Biology, University of Chicago, Chicago, United States
| | - Jihad Aburas
- Department of Neurobiology, University of Chicago, Chicago, United States
| | - Priota Islam
- MRC London Institute of Medical Sciences, London, United Kingdom.,Institute of Clinical Sciences, Imperial College London, London, United Kingdom
| | - André Ex Brown
- MRC London Institute of Medical Sciences, London, United Kingdom.,Institute of Clinical Sciences, Imperial College London, London, United Kingdom
| | - Paschalis Kratsios
- Department of Neurobiology, University of Chicago, Chicago, United States.,Committee on Neurobiology, University of Chicago, Chicago, United States.,Cell and Molecular Biology Program, University of Chicago, Chicago, United States.,Committee on Development, Regeneration and Stem Cell Biology, University of Chicago, Chicago, United States.,The Grossman Institute for Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, United States
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5
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Kojo S, Ohno-Oishi M, Wada H, Nieke S, Seo W, Muroi S, Taniuchi I. Constitutive CD8 expression drives innate CD8 + T-cell differentiation via induction of iNKT2 cells. Life Sci Alliance 2020; 3:3/2/e202000642. [PMID: 31980555 PMCID: PMC6985454 DOI: 10.26508/lsa.202000642] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 01/16/2020] [Accepted: 01/17/2020] [Indexed: 01/26/2023] Open
Abstract
Temporal down-regulation of the CD8 co-receptor after receiving positive-selection signals has been proposed to serve as an important determinant to segregate helper versus cytotoxic lineages by generating differences in the duration of TCR signaling between MHC-I and MHC-II selected thymocytes. By contrast, little is known about whether CD8 also modulates TCR signaling engaged by the non-classical MHC-I-like molecule, CD1d, during development of invariant natural killer T (iNKT) cells. Here, we show that constitutive transgenic CD8 expression resulted in enhanced differentiation of innate memory-like CD8+ thymocytes in both a cell-intrinsic and cell-extrinsic manner, the latter being accomplished by an increase in the IL-4-producing iNKT2 subset. Skewed iNKT2 differentiation requires cysteine residues in the intracellular domain of CD8α that are essential for transmitting cellular signaling. Collectively, these findings shed a new light on the relevance of CD8 down-regulation in shaping the balance of iNKT-cell subsets by modulating TCR signaling.
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Affiliation(s)
- Satoshi Kojo
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Michiko Ohno-Oishi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Hisashi Wada
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Sebastian Nieke
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Wooseok Seo
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Sawako Muroi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Ichiro Taniuchi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
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6
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Ruscher R, Hogquist KA. Development, ontogeny, and maintenance of TCRαβ + CD8αα IEL. Curr Opin Immunol 2019; 58:83-88. [PMID: 31146182 DOI: 10.1016/j.coi.2019.04.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 04/19/2019] [Indexed: 02/07/2023]
Abstract
The intestinal epithelium is the outermost cellular layer that separates the body from the gut lumen. The integrity of this protective mucosal barrier is crucial and maintained by specialized cells-intraepithelial lymphocytes (IEL). Much research has been conducted on these cells and our overall understanding of them is increasing rapidly. In this review we focus on the TCRαβ+ subset of CD8αα IEL. We discuss recent studies that shed light on the development, ontogeny, maintenance, and functional characteristics of CD8αα IEL, and highlight yet unanswered questions for future studies.
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Affiliation(s)
- Roland Ruscher
- Center for Immunology and Department of Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN, USA
| | - Kristin A Hogquist
- Center for Immunology and Department of Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN, USA.
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7
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Gülich AF, Preglej T, Hamminger P, Alteneder M, Tizian C, Orola MJ, Muroi S, Taniuchi I, Ellmeier W, Sakaguchi S. Differential Requirement of Cd8 Enhancers E8 I and E8 VI in Cytotoxic Lineage T Cells and in Intestinal Intraepithelial Lymphocytes. Front Immunol 2019; 10:409. [PMID: 30915074 PMCID: PMC6421288 DOI: 10.3389/fimmu.2019.00409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 02/15/2019] [Indexed: 01/15/2023] Open
Abstract
CD8 expression in T lymphocytes is tightly regulated by the activity of at least six Cd8 enhancers (E8I-E8VI), however their complex developmental stage-, subset-, and lineage-specific interplays are incompletely understood. Here we analyzed ATAC-seq data on the Immunological Genome Project database and identified a similar developmental regulation of chromatin accessibility of a subregion of E8I, designated E8I-core, and of E8VI. Loss of E8I-core led to a similar reduction in CD8 expression in naïve CD8+ T cells and in IELs as observed in E8 I -/- mice, demonstrating that we identified the core enhancer region of E8I. While E8 VI -/- mice displayed a mild reduction in CD8 expression levels on CD8SP thymocytes and peripheral CD8+ T cells, CD8 levels were further reduced upon combined deletion of E8I-core and E8VI. Moreover, activated E8 I -core-/- E8 VI -/- CD8+ T cells lost CD8 expression to a greater degree than E8 I -core-/- and E8 VI -/- CD8+ T cells, suggesting that the combined activity of both enhancers is required for establishment and maintenance of CD8 expression before and after TCR activation. Finally, we observed a severe reduction of CD4 CTLs among the TCRβ+CD4+ IEL population in E8 I -core-/- but not E8 VI -/- mice. Such a reduction was not observed in Cd8a -/- mice, indicating that E8I-core controls the generation of CD4 CTLs independently of its role in Cd8a gene regulation. Further, the combined deletion of E8I-core and E8VI restored CD4 CTL subsets, suggesting an antagonistic function of E8VI in the generation of CD4 CTLs. Together, our study demonstrates a complex utilization and interplay of E8I-core and E8VI in regulating CD8 expression in cytotoxic lineage T cells and in IELs. Moreover, we revealed a novel E8I-mediated regulatory mechanism controlling the generation of intestinal CD4 CTLs.
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Affiliation(s)
- Alexandra Franziska Gülich
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Teresa Preglej
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Patricia Hamminger
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Marlis Alteneder
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Caroline Tizian
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Maria Jonah Orola
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Sawako Muroi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan
| | - Ichiro Taniuchi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan
| | - Wilfried Ellmeier
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Shinya Sakaguchi
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
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8
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Li H, Tsokos MG, Bickerton S, Sharabi A, Li Y, Moulton VR, Kong P, Fahmy TM, Tsokos GC. Precision DNA demethylation ameliorates disease in lupus-prone mice. JCI Insight 2018; 3:120880. [PMID: 30135300 DOI: 10.1172/jci.insight.120880] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 07/19/2018] [Indexed: 12/22/2022] Open
Abstract
Defective DNA methylation in T cells leads to a series of T cell abnormalities in lupus; however, the full effect of T cell lineage-specific DNA methylation on disease expression has not been explored. Here, we show that 5-azacytidine, a DNA methyltransferase inhibitor, targeted to either CD4 or CD8 T cells in mice with established disease using a nanolipogel delivery system dramatically ameliorates lupus-related pathology through distinct mechanisms. In vivo targeted delivery of 5-azacytidine into CD4 T cells favors the expansion and function of Foxp3+ Tregs, whereas targeted delivery to CD8 T cells enhances the cytotoxicity and restrains the expansion of pathogenic TCR-αβ+CD4-CD8- double-negative T cells. Our results signify the importance of cell-specific inhibition of DNA methylation in the treatment of established lupus.
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Affiliation(s)
- Hao Li
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Maria G Tsokos
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Amir Sharabi
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Yi Li
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Vaishali R Moulton
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Tarek M Fahmy
- Department of Biomedical Engineering.,Department of Immunobiology, and.,Department of Chemical and Environmental Engineering, Yale University School of Medicine, New Haven, Connecticut, USA
| | - George C Tsokos
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
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9
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Brandt D, Hedrich CM. TCRαβ +CD3 +CD4 -CD8 - (double negative) T cells in autoimmunity. Autoimmun Rev 2018; 17:422-430. [PMID: 29428806 DOI: 10.1016/j.autrev.2018.02.001] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 12/07/2017] [Indexed: 12/14/2022]
Abstract
TCRαβ+CD3+CD4-CD8- "double negative" (DN) T cells comprise a small subset of mature peripheral T cells. The origin and function of DN T cells are somewhat unclear and discussed controversially. While DN T cells resemble a rare and heterogeneous T cell subpopulation in healthy individuals, numbers of TCRαβ+ DN T cells are expanded in several inflammatory conditions, where they also exhibit distinct effector phenotypes and infiltrate inflamed tissues. Thus, DN T cells may be involved in systemic inflammation and tissue damage in autoimmune/inflammatory conditions, including SLE, Sjögren's syndrome, and psoriasis. Here, the current understanding of the origin and phenotype of DN T cells, and their role in the instruction of immune responses, autoimmunity and inflammation will be discussed in health and disease.
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Affiliation(s)
- D Brandt
- Division of Pediatric Rheumatology and Immunology, Children's Hospital Dresden, Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - C M Hedrich
- Division of Pediatric Rheumatology and Immunology, Children's Hospital Dresden, Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany; Department of Women's & Children's Health, Institute of Translational Medicine, University of Liverpool, Liverpool, UK; Department of Paediatric Rheumatology, Alder Hey Children's NHS Foundation Trust Hospital, Liverpool, UK.
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10
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Issuree PDA, Ng CP, Littman DR. Heritable Gene Regulation in the CD4:CD8 T Cell Lineage Choice. Front Immunol 2017; 8:291. [PMID: 28382035 PMCID: PMC5360760 DOI: 10.3389/fimmu.2017.00291] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/28/2017] [Indexed: 12/04/2022] Open
Abstract
The adaptive immune system is dependent on functionally distinct lineages of T cell antigen receptor αβ-expressing T cells that differentiate from a common progenitor in the thymus. CD4+CD8+ progenitor thymocytes undergo selection following interaction with MHC class I and class II molecules bearing peptide self-antigens, giving rise to CD8+ cytotoxic and CD4+ helper or regulatory T cell lineages, respectively. The strict correspondence of CD4 and CD8 expression with distinct cellular phenotypes has made their genes useful surrogates for investigating molecular mechanisms of lineage commitment. Studies of Cd4 and Cd8 transcriptional regulation have uncovered cis-regulatory elements that are critical for mediating epigenetic modifications at distinct stages of development to establish heritable transcriptional programs. In this review, we examine the epigenetic mechanisms involved in Cd4 and Cd8 gene regulation during T cell lineage specification and highlight the features that make this an attractive system for uncovering molecular mechanisms of heritability.
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Affiliation(s)
- Priya D A Issuree
- The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine , New York, NY , USA
| | - Charles P Ng
- The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine , New York, NY , USA
| | - Dan R Littman
- The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, NY, USA; Howard Hughes Medical Institute, New York University School of Medicine, New York, NY, USA
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11
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Abstract
There has been speculation as to how bi-potent CD4(+) CD8(+) double-positive precursor thymocytes choose their distinct developmental fate, becoming either CD4(+) helper or CD8(+) cytotoxic T cells. Based on the clear correlation of αβT cell receptor (TCR) specificity to major histocompatibility complex (MHC) classes with this lineage choice, various studies have attempted to resolve this question by examining the cellular signaling events initiated by TCR engagements, a strategy referred to as a 'top-down' approach. On the other hand, based on the other correlation of CD4/CD8 co-receptor expression with its selected fate, other studies have addressed this question by gradually unraveling the sequential mechanisms that control the phenotypic outcome of this fate decision, a method known as the 'bottom-up' approach. Bridging these two approaches will contribute to a more comprehensive understanding of how TCR signals are coupled with developmental programs in the nucleus. Advances made during the last two decades seemed to make these two approaches more closely linked. For instance, identification of two transcription factors, ThPOK and Runx3, which play central roles in the development of helper and cytotoxic lineages, respectively, provided significant insights into the transcriptional network that controls a CD4/CD8 lineage choice. This review summarizes achievements made using the 'bottom-up' approach, followed by a perspective on future pathways toward coupling TCR signaling with nuclear programs.
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Affiliation(s)
- Ichiro Taniuchi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Kanagawa, Japan
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12
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Nguyen MLT, Jones SA, Prier JE, Russ BE. Transcriptional Enhancers in the Regulation of T Cell Differentiation. Front Immunol 2015; 6:462. [PMID: 26441967 PMCID: PMC4563239 DOI: 10.3389/fimmu.2015.00462] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 08/24/2015] [Indexed: 12/24/2022] Open
Abstract
The changes in phenotype and function that characterize the differentiation of naïve T cells to effector and memory states are underscored by large-scale, coordinated, and stable changes in gene expression. In turn, these changes are choreographed by the interplay between transcription factors and epigenetic regulators that act to restructure the genome, ultimately ensuring lineage-appropriate gene expression. Here, we focus on the mechanisms that control T cell differentiation, with a particular focus on the role of regulatory elements encoded within the genome, known as transcriptional enhancers (TEs). We discuss the central role of TEs in regulating T cell differentiation, both in health and disease.
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Affiliation(s)
- Michelle L T Nguyen
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne , Melbourne, VIC , Australia
| | - Sarah A Jones
- Monash University Centre for Inflammatory Disease, School of Clinical Sciences at Monash Health , Melbourne, VIC , Australia
| | - Julia E Prier
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne , Melbourne, VIC , Australia
| | - Brendan E Russ
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne , Melbourne, VIC , Australia
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13
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Jeschke JC, Williams CB. Editorial: Crossing the divide: a novel Cd8 enhancer with activity in CTLs and CD8αα+ dendritic cells. J Leukoc Biol 2015; 97:623-5. [PMID: 25828836 DOI: 10.1189/jlb.2ce1214-606r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Jonathan C Jeschke
- Section of Rheumatology, Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Calvin B Williams
- Section of Rheumatology, Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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14
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Sakaguchi S, Hombauer M, Hassan H, Tanaka H, Yasmin N, Naoe Y, Bilic I, Moser MA, Hainberger D, Mayer H, Seiser C, Bergthaler A, Taniuchi I, Ellmeier W. A novel Cd8-cis-regulatory element preferentially directs expression in CD44hiCD62L+ CD8+ T cells and in CD8αα+ dendritic cells. J Leukoc Biol 2014; 97:635-44. [PMID: 25548254 DOI: 10.1189/jlb.1hi1113-597rr] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
CD8 coreceptor expression is dynamically regulated during thymocyte development and is tightly controlled by the activity of at least 5 different cis-regulatory elements. Despite the detailed characterization of the Cd8 loci, the regulation of the complex expression pattern of CD8 cannot be fully explained by the activity of the known Cd8 enhancers. In this study, we revisited the Cd8ab gene complex with bioinformatics and transgenic reporter gene expression approaches to search for additional Cd8 cis-regulatory elements. This led to the identification of an ECR (ECR-4), which in transgenic reporter gene expression assays, directed expression preferentially in CD44(hi)CD62L(+) CD8(+) T cells, including innate-like CD8(+) T cells. ECR-4, designated as Cd8 enhancer E8VI, was bound by Runx/CBFβ complexes and Bcl11b, indicating that E8VI is part of the cis-regulatory network that recruits transcription factors to the Cd8ab gene complex in CD8(+) T cells. Transgenic reporter expression was maintained in LCMV-specific CD8(+) T cells upon infection, although short-term, in vitro activation led to a down-regulation of E8VI activity. Finally, E8VI directed transgene expression also in CD8αα(+) DCs but not in CD8αα-expressing IELs. Taken together, we have identified a novel Cd8 enhancer that directs expression in CD44(hi)CD62L(+) CD8(+) T cells, including innate-like and antigen-specific effector/memory CD8(+) T cells and in CD8αα(+) DCs, and thus, our data provide further insight into the cis-regulatory networks that control CD8 expression.
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Affiliation(s)
- Shinya Sakaguchi
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Matthias Hombauer
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Hammad Hassan
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Hirokazu Tanaka
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Nighat Yasmin
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Yoshinori Naoe
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Ivan Bilic
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Mirjam A Moser
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Daniela Hainberger
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Herbert Mayer
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Christian Seiser
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Andreas Bergthaler
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Ichiro Taniuchi
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Wilfried Ellmeier
- *Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, and Institute of Vascular Biology, Medical University of Vienna, Austria; Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa, Japan; and CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
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15
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Abstract
During blood cell development, hematopoietic stem cells generate diverse mature populations via several rounds of binary fate decisions. At each bifurcation, precursors adopt one fate and inactivate the alternative fate either stochastically or in response to extrinsic stimuli and stably maintain the selected fates. Studying of these processes would contribute to better understanding of etiology of immunodeficiency and leukemia, which are caused by abnormal gene regulation during the development of hematopoietic cells. The CD4(+) helper versus CD8(+) cytotoxic T-cell fate decision serves as an excellent model to study binary fate decision processes. These two cell types are derived from common precursors in the thymus. Positive selection of their TCRs by self-peptide presented on either MHC class I or class II triggers their fate decisions along with mutually exclusive retention and silencing of two coreceptors, CD4 and CD8. In the past few decades, extensive effort has been made to understand the T-cell fate decision processes by studying regulation of genes encoding the coreceptors and selection processes. These studies have identified several key transcription factors and gene regulatory networks. In this chapter, I will discuss recent advances in our understanding of the binary cell fate decision processes of T cells.
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Affiliation(s)
- Takeshi Egawa
- Department of Pathology and Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA.
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16
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Histone acetylation mediated by Brd1 is crucial for Cd8 gene activation during early thymocyte development. Nat Commun 2014; 5:5872. [PMID: 25519988 DOI: 10.1038/ncomms6872] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 11/14/2014] [Indexed: 11/08/2022] Open
Abstract
During T-cell development, Cd8 expression is controlled via dynamic regulation of its cis-regulatory enhancer elements. Insufficiency of enhancer activity causes variegated Cd8 expression in CD4(+)CD8(+) double-positive (DP) thymocytes. Brd1 is a subunit of the Hbo1 histone acetyltransferase (HAT) complex responsible for acetylation of histone H3 at lysine 14 (H3K14). Here we show that deletion of Brd1 in haematopoietic progenitors causes variegated expression of Cd8, resulting in the appearance of CD4(+)CD8(-)TCRβ(-/low) thymocytes indistinguishable from DP thymocytes in their properties. Biochemical analysis confirms that Brd1 forms a HAT complex with Hbo1 in thymocytes. ChIP analysis demonstrates that Brd1 localizes at the known enhancers in the Cd8 genes and is responsible for acetylation at H3K14. These findings indicate that the Brd1-mediated HAT activity is crucial for efficient activation of Cd8 expression via acetylation at H3K14, which serves as an epigenetic mark that promotes the recruitment of transcription machinery to the Cd8 enhancers.
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17
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Van Kaer L, Algood HMS, Singh K, Parekh VV, Greer MJ, Piazuelo MB, Weitkamp JH, Matta P, Chaturvedi R, Wilson KT, Olivares-Villagómez D. CD8αα⁺ innate-type lymphocytes in the intestinal epithelium mediate mucosal immunity. Immunity 2014; 41:451-464. [PMID: 25220211 DOI: 10.1016/j.immuni.2014.08.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 08/08/2014] [Indexed: 01/22/2023]
Abstract
Innate immune responses are critical for mucosal immunity. Here we describe an innate lymphocyte population, iCD8α cells, characterized by expression of CD8α homodimers. iCD8α cells exhibit innate functional characteristics such as the capacity to engulf and kill bacteria. Development of iCD8α cells depends on expression of interleukin-2 receptor γ chain (IL-2Rγc), IL-15, and the major histocompatibility complex (MHC) class Ib protein H2-T3, also known as the thymus leukemia antigen or TL. While lineage tracking experiments indicated that iCD8α cells have a lymphoid origin, their development was independent of the transcriptional suppressor Id2, suggesting that these cells do not belong to the family of innate lymphoid cells. Finally, we identified cells with a similar phenotype in humans, which were profoundly depleted in newborns with necrotizing enterocolitis. These findings suggest a critical role of iCD8α cells in immune responses associated with the intestinal epithelium.
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Affiliation(s)
- Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Holly M Scott Algood
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37232, USA; Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Kshipra Singh
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Vrajesh V Parekh
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Michael J Greer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - M Blanca Piazuelo
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Jörn-Hendrik Weitkamp
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Pranathi Matta
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Rupesh Chaturvedi
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Keith T Wilson
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37232, USA; Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Danyvid Olivares-Villagómez
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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18
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Boucheron N, Tschismarov R, Goeschl L, Moser MA, Lagger S, Sakaguchi S, Winter M, Lenz F, Vitko D, Breitwieser FP, Müller L, Hassan H, Bennett KL, Colinge J, Schreiner W, Egawa T, Taniuchi I, Matthias P, Seiser C, Ellmeier W. CD4(+) T cell lineage integrity is controlled by the histone deacetylases HDAC1 and HDAC2. Nat Immunol 2014; 15:439-448. [PMID: 24681565 PMCID: PMC4346201 DOI: 10.1038/ni.2864] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 03/05/2014] [Indexed: 12/15/2022]
Abstract
Molecular mechanisms that maintain lineage integrity of helper T cells are largely unknown. Here we show histone deacetylases 1 and 2 (HDAC1 and HDAC2) as crucial regulators of this process. Loss of HDAC1 and HDAC2 during late T cell development led to the appearance of major histocompatibility complex (MHC) class II-selected CD4(+) helper T cells that expressed CD8-lineage genes such as Cd8a and Cd8b1. HDAC1 and HDAC2-deficient T helper type 0 (TH0) and TH1 cells further upregulated CD8-lineage genes and acquired a CD8(+) effector T cell program in a manner dependent on Runx-CBFβ complexes, whereas TH2 cells repressed features of the CD8(+) lineage independently of HDAC1 and HDAC2. These results demonstrate that HDAC1 and HDAC2 maintain integrity of the CD4 lineage by repressing Runx-CBFβ complexes that otherwise induce a CD8(+) effector T cell-like program in CD4(+) T cells.
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Affiliation(s)
- Nicole Boucheron
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Roland Tschismarov
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Lisa Goeschl
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090 Vienna, Austria
- Division of Rheumatology, Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Mirjam A. Moser
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, Medical University of Vienna, 1030 Vienna, Austria
| | - Sabine Lagger
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, Medical University of Vienna, 1030 Vienna, Austria
| | - Shinya Sakaguchi
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Mircea Winter
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, Medical University of Vienna, 1030 Vienna, Austria
| | - Florian Lenz
- Division of Biosimulation and Bioinformatics, Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, 1090 Vienna, Austria
| | - Dijana Vitko
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria
| | - Florian P. Breitwieser
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria
| | - Lena Müller
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Hammad Hassan
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Keiryn L. Bennett
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria
| | - Jacques Colinge
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria
| | - Wolfgang Schreiner
- Division of Biosimulation and Bioinformatics, Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, 1090 Vienna, Austria
| | - Takeshi Egawa
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ichiro Taniuchi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences (IMS-RCAI), Yokohama, Kanagawa 230-0045, Japan
| | - Patrick Matthias
- Friedrich Miescher Institute for Biomedical Research, Novartis Research Foundation, 4058 Basel, Switzerland and University of Basel, Faculty of Sciences, 4051 Basel, Switzerland
| | - Christian Seiser
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Vienna Biocenter, Medical University of Vienna, 1030 Vienna, Austria
| | - Wilfried Ellmeier
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, A-1090 Vienna, Austria
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19
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Hedrich CM, Crispín JC, Rauen T, Ioannidis C, Koga T, Rodriguez Rodriguez N, Apostolidis SA, Kyttaris VC, Tsokos GC. cAMP responsive element modulator (CREM) α mediates chromatin remodeling of CD8 during the generation of CD3+ CD4- CD8- T cells. J Biol Chem 2013; 289:2361-70. [PMID: 24297179 DOI: 10.1074/jbc.m113.523605] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
TCR-αβ(+)CD3(+)CD4(-)CD8(-) "double negative" T cells are expanded in the peripheral blood of patients with systemic lupus erythematosus (SLE) and lupus-prone mice. Double negative T cells have been claimed to derive from CD8(+) cells that down-regulate CD8 co-receptors and acquire a distinct effector phenotype that includes the expression of proinflammatory cytokines. This, along with the fact that double negative T cells have been documented in inflamed organs, suggests that they may contribute to disease expression and tissue damage. We recently linked the transcription factor cAMP responsive element modulator (CREM) α, which is expressed at increased levels in T cells from SLE patients and lupus prone MRL/lpr mice, with trans-repression of a region syntenic to the murine CD8b promoter. However, the exact molecular mechanisms that result in a stable silencing of both CD8A and CD8B genes remain elusive. Here, we demonstrate that CREMα orchestrates epigenetic remodeling of the CD8 cluster through the recruitment of DNA methyltransferase (DNMT) 3a and histone methyltransferase G9a. Thus, we propose that CREMα is essential for the expansion of double negative T cells in SLE. CREMα blockade may have therapeutic value in autoimmune disorders with DN T cell expansion.
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Affiliation(s)
- Christian M Hedrich
- From the Department of Medicine, Division of Rheumatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02115
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20
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Hedrich CM, Rauen T, Crispin JC, Koga T, Ioannidis C, Zajdel M, Kyttaris VC, Tsokos GC. cAMP-responsive element modulator α (CREMα) trans-represses the transmembrane glycoprotein CD8 and contributes to the generation of CD3+CD4-CD8- T cells in health and disease. J Biol Chem 2013; 288:31880-7. [PMID: 24047902 DOI: 10.1074/jbc.m113.508655] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
T cell receptor-αβ(+) CD3(+)CD4(-)CD8(-) "double-negative" T cells are expanded in the peripheral blood of patients with systemic lupus erythematosus and autoimmune lymphoproliferative syndrome. In both disorders, double-negative T cells infiltrate tissues, induce immunoglobulin production, and secrete proinflammatory cytokines. Double-negative T cells derive from CD8(+) T cells through down-regulation of CD8 surface co-receptors. However, the molecular mechanisms orchestrating this process remain unclear. Here, we demonstrate that the transcription factor cAMP-responsive element modulator α (CREMα), which is expressed at increased levels in T cells from systemic lupus erythematosus patients, contributes to transcriptional silencing of CD8A and CD8B. We provide the first evidence that CREMα trans-represses a regulatory element 5' of the CD8B gene. Therefore, CREMα represents a promising candidate in the search for biomarkers and treatment options in diseases in which double-negative T cells contribute to the pathogenesis.
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Affiliation(s)
- Christian M Hedrich
- From the Division of Rheumatology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02115
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21
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Transcriptional control of CD4 and CD8 coreceptor expression during T cell development. Cell Mol Life Sci 2013; 70:4537-53. [PMID: 23793512 PMCID: PMC3827898 DOI: 10.1007/s00018-013-1393-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 05/27/2013] [Accepted: 05/29/2013] [Indexed: 11/24/2022]
Abstract
The differentiation and function of peripheral helper and cytotoxic T cell lineages is coupled with the expression of CD4 and CD8 coreceptor molecules, respectively. This indicates that the control of coreceptor gene expression is closely linked with the regulation of CD4/CD8 lineage decision of DP thymocytes. Research performed during the last two decades revealed comprehensive mechanistic insight into the developmental stage- and subset/lineage-specific regulation of Cd4, Cd8a and Cd8b1 (Cd8) gene expression. These studies provided important insight into transcriptional control mechanisms during T cell development and into the regulation of cis-regulatory networks in general. Moreover, the identification of transcription factors involved in the regulation of CD4 and CD8 significantly advanced the knowledge of the transcription factor network regulating CD4/CD8 cell-fate choice of DP thymocytes. In this review, we provide an overview of the identification and characterization of CD4/CD8 cis-regulatory elements and present recent progress in our understanding of how these cis-regulatory elements control CD4/CD8 expression during T cell development and in peripheral T cells. In addition, we describe the transcription factors implicated in the regulation of coreceptor gene expression and discuss how these factors are integrated into the transcription factor network that regulates CD4/CD8 cell-fate choice of DP thymocytes.
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22
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Abstract
One of the best studied systems for mammalian chromatin remodeling is transcriptional regulation during T cell development. The variety of these studies have led to important findings in T cell gene regulation and cell fate determination. Importantly, these findings have also advanced our knowledge of the function of remodeling enzymes in mammalian gene regulation. First we briefly present biochemical and cell-free analysis of 3 types of ATP dependent remodeling enzymes (SWI/SNF, Mi2, and ISWI) to construct an intellectual framework to understand how these enzymes might be working. Second, we compare and contrast the function of these enzymes during early (thymic) and late (peripheral) T cell development. Finally, we examine some of the gaps in our present understanding.
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Affiliation(s)
- Andrea L. Wurster
- Laboratory of Molecular Biology and Immunology, National Institute on Aging Intramural Research Program, National Institutes of Health, USA
| | - Michael J. Pazin
- Laboratory of Molecular Biology and Immunology, National Institute on Aging Intramural Research Program, National Institutes of Health, USA
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23
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Adoro S, McCaughtry T, Erman B, Alag A, Van Laethem F, Park JH, Tai X, Kimura M, Wang L, Grinberg A, Kubo M, Bosselut R, Love P, Singer A. Coreceptor gene imprinting governs thymocyte lineage fate. EMBO J 2011; 31:366-77. [PMID: 22036949 PMCID: PMC3261554 DOI: 10.1038/emboj.2011.388] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 09/28/2011] [Indexed: 11/30/2022] Open
Abstract
Double-positive (CD4+CD8+) thymocytes differentiate into CD4+ helper T cells and CD8+ cytotoxic T cells. A knock-in approach replacing CD8-coding sequences with CD4 cDNA shows that it is the expression kinetics of CD8, and not the identity of the coreceptor, that governs thymocyte-lineage fate. Immature thymocytes are bipotential cells that are signalled during positive selection to become either helper- or cytotoxic-lineage T cells. By tracking expression of lineage determining transcription factors during positive selection, we now report that the Cd8 coreceptor gene locus co-opts any coreceptor protein encoded within it to induce thymocytes to express the cytotoxic-lineage factor Runx3 and to adopt the cytotoxic-lineage fate, findings we refer to as ‘coreceptor gene imprinting'. Specifically, encoding CD4 proteins in the endogenous Cd8 gene locus caused major histocompatibility complex class II-specific thymocytes to express Runx3 during positive selection and to differentiate into CD4+ cytotoxic-lineage T cells. Our findings further indicate that coreceptor gene imprinting derives from the dynamic regulation of specific cis Cd8 gene enhancer elements by positive selection signals in the thymus. Thus, for coreceptor-dependent thymocytes, lineage fate is determined by Cd4 and Cd8 coreceptor gene loci and not by the specificity of T-cell antigen receptor/coreceptor signalling. This study identifies coreceptor gene imprinting as a critical determinant of lineage fate determination in the thymus.
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Affiliation(s)
- Stanley Adoro
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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24
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Cd8 enhancer E8I and Runx factors regulate CD8α expression in activated CD8+ T cells. Proc Natl Acad Sci U S A 2011; 108:18330-5. [PMID: 22025728 DOI: 10.1073/pnas.1105835108] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Cd8a and Cd8b1 coreceptor gene (Cd8) expression is tightly controlled during T-cell development by the activity of five Cd8 enhancers (E8(I)-E8(V)). Here we demonstrate a unique transcriptional program regulating CD8 expression during CD8(+) effector T-cell differentiation. The Cd8 enhancer E8(I) and Runx/core-binding factor-β (CBFβ) complexes were required for the establishment of this regulatory circuit, because E8(I)-, Runx3-, or CBFβ-deficient CD8(+) T cells down-regulated CD8α expression during activation. This finding correlated with enhanced repressive histone marks at the Cd8a promoter in the absence of E8(I), and the down-regulation of CD8α expression could be blocked by treating E8(I)-, Runx3-, or CBFβ-deficient CD8(+) T cells with the histone deacetylase inhibitor trichostatin A. Moreover, Runx/CBFβ complexes bound the Cd8ab gene cluster in activated CD8(+) T cells, suggesting direct control of the Cd8a locus. However, CD8(+) effector T cells maintained high levels of CD8α when CBFβ was conditionally deleted after activation. Thus, our data suggest an E8(I)- and Runx3/CBFβ-dependent epigenetic programming of the Cd8a locus during T-cell activation, leading to Runx/CBFβ complex-independent maintenance of CD8α expression in effector T cells.
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25
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Menzel U, Kosteas T, Tolaini M, Killeen N, Roderick K, Kioussis D. Modulation of the murine CD8 gene complex following the targeted integration of human CD2-locus control region sequences. THE JOURNAL OF IMMUNOLOGY 2011; 187:3712-20. [PMID: 21880987 DOI: 10.4049/jimmunol.1100709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The human CD2 (hCD2) locus control region (LCR) inserted in the mouse CD8 gene complex activates expression of the CD8 genes in T cell subsets in which the CD8 locus is normally silenced (e.g., CD4(+) single-positive T cells). In this article, we show that, in conditional mCD8/hCD2-LCR (CD8/LCR) knock-in mice, the continuous presence of the hCD2-LCR is required for this effect. Deletion of the inserted hCD2-LCR in a developmental stage and cell lineage-specific manner revealed that the temporary presence of the LCR during early development does not permanently alter the expression pattern of the CD8 genes. As a result, cells that have been affected by the insertion of the LCR can convert to their destined phenotype once the LCR is removed. DNaseI hypersensitive sites 1 and 2 of the hCD2-LCR influence the expression of the CD8 genes in a similar manner as does the full LCR, whereas insertion of hypersensitive site 3 alone of the LCR does not result in a changed expression pattern. This analysis revealed a dynamic interaction between the hCD2-LCR and the endogenous regulatory elements of the CD8 genes.
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Affiliation(s)
- Ursula Menzel
- Division of Molecular Immunology, National Institute for Medical Research, Medical Research Council, London NW7 1AA, United Kingdom
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26
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Collins A, Hewitt S, Chaumeil J, Sellars M, Micsinai M, Allinne J, Parisi F, Nora EP, Bolland D, Corcoran A, Kluger Y, Bosselut R, Ellmeier W, Chong M, Littman D, Skok J. RUNX transcription factor-mediated association of Cd4 and Cd8 enables coordinate gene regulation. Immunity 2011; 34:303-14. [PMID: 21435585 PMCID: PMC3101577 DOI: 10.1016/j.immuni.2011.03.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 09/07/2010] [Accepted: 12/21/2010] [Indexed: 01/24/2023]
Abstract
T cell fate is associated with mutually exclusive expression of CD4 or CD8 in helper and cytotoxic T cells, respectively. How expression of one locus is temporally coordinated with repression of the other has been a long-standing enigma, though we know RUNX transcription factors activate the Cd8 locus, silence the Cd4 locus, and repress the Zbtb7b locus (encoding the transcription factor ThPOK), which is required for CD4 expression. Here we found that nuclear organization was altered by interplay among members of this transcription factor circuitry: RUNX binding mediated association of Cd4 and Cd8 whereas ThPOK binding kept the loci apart. Moreover, targeted deletions within Cd4 modulated CD8 expression and pericentromeric repositioning of Cd8. Communication between Cd4 and Cd8 thus appears to enable long-range epigenetic regulation to ensure that expression of one excludes the other in mature CD4 or CD8 single-positive (SP) cells.
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Affiliation(s)
- Amélie Collins
- Molecular Pathogenesis Program, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Susannah L. Hewitt
- Department of Pathology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Julie Chaumeil
- Department of Pathology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - MacLean Sellars
- Molecular Pathogenesis Program, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Mariann Micsinai
- New York University Center for Health Informatics and Bioinformatics, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
- NYU Cancer Institute, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
- Department of Pathology and Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Jeanne Allinne
- Department of Pathology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Fabio Parisi
- Department of Pathology and Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Elphège P. Nora
- Institut Curie, CNRS UMR3215, INSERM U934, 75724 Paris Cedex 05, France
| | - Dan J. Bolland
- The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK
| | - Anne E. Corcoran
- The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK
| | - Yuval Kluger
- Department of Pathology and Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Remy Bosselut
- Laboratory of Immune Cell Biology, Center for Cancer Research (CCR), NCI, NIH, Bethesda, MD 20892-4259, USA
| | - Wilfried Ellmeier
- Division of Immunobiology, Institute of Immunology, Medical University of Vienna, Lazarettgasse 19, A-1090 Vienna, Austria
| | - Mark M.W. Chong
- Molecular Pathogenesis Program, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Dan R. Littman
- Molecular Pathogenesis Program, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
- Howard Hughes Medical Institute
| | - Jane A. Skok
- Department of Pathology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
- Division of Infection and Immunity, The Department of Immunology and Molecular Pathology, University College London, London W1T 4JF, UK
- Corresponding author
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27
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Harker N, Garefalaki A, Menzel U, Ktistaki E, Naito T, Georgopoulos K, Kioussis D. Pre-TCR signaling and CD8 gene bivalent chromatin resolution during thymocyte development. THE JOURNAL OF IMMUNOLOGY 2011; 186:6368-77. [PMID: 21515796 DOI: 10.4049/jimmunol.1003567] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The CD8 gene is silent in CD4(-)CD8(-) double-negative thymocytes, expressed in CD4(+)CD8(+) double-positive cells, and silenced in cells committing to the CD4(+) single-positive (SP) lineage, remaining active in the CD8(+) SP lineage. In this study, we show that the chromatin of the CD8 locus is remodeled in C57BL/6 and B6/J Rag1(-/-) MOM double-negative thymocytes as indicated by DNaseI hypersensitivity and widespread bivalent chromatin marks. Pre-TCR signaling coincides with chromatin bivalency resolution into monovalent activating modifications in double-positive and CD8 SP cells. Shortly after commitment to CD4 SP cell lineage, monovalent repressive characteristics and chromatin inaccessibility are established. Differential binding of Ikaros, NuRD, and heterochromatin protein 1α on the locus during these processes may participate in the complex regulation of CD8.
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Affiliation(s)
- Nicola Harker
- Division of Molecular Immunology, National Institute for Medical Research, Medical Research Council, London NW7 1AA, United Kingdom.
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28
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The epigenetic landscape of lineage choice: lessons from the heritability of CD4 and CD8 expression. Curr Top Microbiol Immunol 2011; 356:165-88. [PMID: 21989924 PMCID: PMC4417357 DOI: 10.1007/82_2011_175] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Developing αβ T cells choose between the helper and cytotoxic lineages, depending upon the specificity of their T cell receptors for MHC molecules. The expression of the CD4 co-receptor on helper cells and the CD8 co-receptor on cytotoxic cells is intimately linked to this decision, and their regulation at the transcriptional level has been the subject of intense study to better understand lineage choice. Indeed, as the fate of developing T cells is decided, the expression status of these genes is accordingly locked. Genetic models have revealed important transcriptional elements and the ability to manipulate these elements in the framework of development has added a new perspective on the temporal nature of their function and the epigenetic maintenance of gene expression. We examine here novel insights into epigenetic mechanisms that have arisen through the study of these genes.
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29
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Abstract
The helper versus cytotoxic-lineage choice of CD4(+)CD8(+) DP thymocytes correlates with MHC restriction of their T cell receptors and the termination of either CD8 or CD4 coreceptor expression. It has been hypothesized that transcription factors regulating the expression of the Cd4/Cd8 coreceptor genes must play a role in regulating the lineage decision of DP thymocytes. Indeed, progress made during the past decade led to the identification of several transcription factors that regulate CD4/CD8 expression that are as well important regulators of helper/cytotoxic cell fate choice. These studies provided insight into the molecular link between the regulation of coreceptor expression and lineage decision. However, studies initiated by the identification of ThPOK, a central transcription factor for helper T cell development, have offered another perspective on the cross-regulation between these two processes. Here, we review advances in our understanding of regulatory circuits composed of transcription factors and their link to epigenetic mechanisms, which play essential roles in specifying and sealing cell lineage identity during the CD4/CD8 commitment process of DP thymocytes.
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Affiliation(s)
- Ichiro Taniuchi
- Laboratory for Transcriptional Regulation, Research Center for Allergy and Immunology, RIKEN, Suehiro-cho, Turumi-ku, Yokohama, Kanagawa, Japan
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30
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Yao X, Nie H, Rojas IC, Harriss JV, Maika SD, Gottlieb PD, Rathbun G, Tucker PW. The L2a element is a mouse CD8 silencer that interacts with MAR-binding proteins SATB1 and CDP. Mol Immunol 2010; 48:153-63. [PMID: 20884053 DOI: 10.1016/j.molimm.2010.08.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 07/29/2010] [Accepted: 08/24/2010] [Indexed: 02/07/2023]
Abstract
Previous transgenic-reporter and targeted-deletion studies indicate that the subset-specific expression of CD8αβ heterodimers is controlled by multiple enhancer activities, since no silencer elements had been found within the locus. We have identified such a silencer as L2a, a previously characterized ∼ 220 bp nuclear matrix associating region (MAR) located ∼ 4.5 kb upstream of CD8α. L2a transgenes driven by the E8(I) enhancer showed no reporter expression in thymic subsets or T cells in splenic, inguinal and mesenteric lymph node peripheral T cells. Deletion of L2a resulted in significant reporter de-repression, even in the CD4(+)CD8(+) double positive (DP) thymocyte population. L2a contains binding sites for two MAR-interacting proteins, SATB1 and CDP. We found that that binding of these factors was markedly influenced by the content and spacing of L2a sub-motifs (L and S) and that SATB1 binds preferentially to the L motif both in vitro and in vivo. A small fraction of the transgenic CD8 single positive (SP) thymocytes and peripheral CD8(+) T cells bypassed L2a-silencing to give rise to variegated expression of the transgenic reporter. Crossing the L2a-containing transgene onto a SATB1 knockdown background enhanced variegated expression, suggesting that SATB1 is critical in overcoming L2a-silenced transcription.
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Affiliation(s)
- Xin Yao
- Section of Molecular Genetics and Microbiology, Institute for Cellular and Molecular Biology, University of Texas at Austin, 1 University Station A5000, Austin, TX 78721-0162, USA
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31
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Replication allows inactivation of a knocked-in locus control region in inappropriate cell lineages. Proc Natl Acad Sci U S A 2010; 107:16928-33. [PMID: 20837519 DOI: 10.1073/pnas.1010317107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
To study the influence of a locus control region (LCR) on the expression of a highly characterized, developmentally regulated locus, we have targeted the hCD2-LCR as a single copy into the endogenous mouse CD8 gene complex. Two knock-in mouse lines that differ in the integration site of the hCD2-LCR within the mCD8 gene complex were generated, and the influence on expression of the CD8 coreceptor was assessed. In these mice the normal developmental silencing of the CD8 genes in the CD4 lineage is deregulated, and the mice develop CD4(+) cells that also express the CD8 genes. This is accompanied by the physical maintenance of the CD8 genes within an extended loop away from their subchromosomal territory. Further analysis of these mice revealed unexpected fluid chromatin dynamics, whereby the LCR can be initially dominant over the endogenous CD8 gene-repressive regulatory processes present in CD4(+) cells but is continuously contested by them, resulting in the eventual inactivation of the inserted LCR, probably as a result of multiple rounds of replication.
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32
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Zhang S, Rozell M, Verma RK, Albu DI, Califano D, VanValkenburgh J, Merchant A, Rangel-Moreno J, Randall TD, Jenkins NA, Copeland NG, Liu P, Avram D. Antigen-specific clonal expansion and cytolytic effector function of CD8+ T lymphocytes depend on the transcription factor Bcl11b. ACTA ACUST UNITED AC 2010; 207:1687-99. [PMID: 20660613 PMCID: PMC2916134 DOI: 10.1084/jem.20092136] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
CD8(+) T lymphocytes mediate the immune response to viruses, intracellular bacteria, protozoan parasites, and tumors. We provide evidence that the transcription factor Bcl11b/Ctip2 controls hallmark features of CD8(+) T cell immunity, specifically antigen (Ag)-dependent clonal expansion and cytolytic activity. The reduced clonal expansion in the absence of Bcl11b was caused by altered proliferation during the expansion phase, with survival remaining unaffected. Two genes with critical roles in TCR signaling were deregulated in Bcl11b-deficient CD8(+) T cells, CD8 coreceptor and Plcgamma1, both of which may contribute to the impaired responsiveness. Bcl11b was found to bind the E8I, E8IV, and E8V, but not E8II or E8III, enhancers. Thus, Bcl11b is one of the transcription factors implicated in the maintenance of optimal CD8 coreceptor expression in peripheral CD8(+) T cells through association with specific enhancers. Short-lived Klrg1(hi)CD127(lo) effector CD8(+) T cells were formed during the course of infection in the absence of Bcl11b, albeit in smaller numbers, and their Ag-specific cytolytic activity on a per-cell basis was altered, which was associated with reduced granzyme B and perforin.
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Affiliation(s)
- Shuning Zhang
- Center for Cell Biology and Cancer Research, Albany Medical College, Albany, NY 12208, USA
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33
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Ktistaki E, Garefalaki A, Williams A, Andrews SR, Bell DM, Foster KE, Spilianakis CG, Flavell RA, Kosyakova N, Trifonov V, Liehr T, Kioussis D. CD8 locus nuclear dynamics during thymocyte development. THE JOURNAL OF IMMUNOLOGY 2010; 184:5686-95. [PMID: 20404270 DOI: 10.4049/jimmunol.1000170] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nuclear architecture and chromatin reorganization have recently been shown to orchestrate gene expression and act as key players in developmental pathways. To investigate how regulatory elements in the mouse CD8 gene locus are arranged in space and in relation to each other, three-dimensional fluorescence in situ hybridization and chromosome conformation capture techniques were employed to monitor the repositioning of the locus in relation to its subchromosomal territory and to identify long-range interactions between the different elements during development. Our data demonstrate that CD8 gene expression in murine lymphocytes is accompanied by the relocation of the locus outside its subchromosomal territory. Similar observations in the CD4 locus point to a rather general phenomenon during T cell development. Furthermore, we show that this relocation of the CD8 gene locus is associated with a clustering of regulatory elements forming a tight active chromatin hub in CD8-expressing cells. In contrast, in nonexpressing cells, the gene remains close to the main body of its chromosomal domain and the regulatory elements appear not to interact with each other.
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Affiliation(s)
- Eleni Ktistaki
- Division of Molecular Immunology, Medical Research Council, National Institute for Medical Research, London, United Kingdom
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34
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Sakaguchi S, Hombauer M, Bilic I, Naoe Y, Schebesta A, Taniuchi I, Ellmeier W. The zinc-finger protein MAZR is part of the transcription factor network that controls the CD4 versus CD8 lineage fate of double-positive thymocytes. Nat Immunol 2010; 11:442-8. [PMID: 20383150 DOI: 10.1038/ni.1860] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 03/03/2010] [Indexed: 12/12/2022]
Abstract
The CD4 versus CD8 lineage specification of thymocytes is linked to coreceptor expression. The transcription factor MAZR has been identified as an important regulator of Cd8 expression. Here we show that variegated CD8 expression by loss of Cd8 enhancers was reverted in MAZR-deficient mice, which confirms that MAZR negatively regulates the Cd8 loci during the transition to the double-positive (DP) stage. Moreover, loss of MAZR led to partial redirection of major histocompatibility complex (MHC) class I-restricted thymocytes into CD4(+) helper-like T cells, which correlated with derepression of Th-POK, a central transcription factor for helper-lineage development. MAZR bound the silencer of the gene encoding Th-POK, which indicated direct regulation of this locus by MAZR. Thus, MAZR is part of the transcription factor network that regulates the CD8 lineage differentiation of DP thymocytes.
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Affiliation(s)
- Shinya Sakaguchi
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
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35
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Abstract
"The beginning of wisdom is found in doubting; by doubting we come to question, and by seeking we may come upon the truth." -Pierre Abélard. CD8 is a glycoprotein expressed on hematopoietic cells. Two isoforms of CD8, CD8alphabeta and CD8alphaalpha, have been identified that are distinct in their expression and function. Whereas CD8alphabeta serves as a T cell receptor (TCR) coreceptor to enhance the functional avidity and is constitutively expressed on MHC class I-restricted T cells, CD8alphaalpha marks T cells that are distinct from the conventional thymus-selected and MHC-restricted CD4(+) or CD8alphabeta(+) T cells. Inconsistent with a coreceptor function, CD8alphaalpha decreases antigen sensitivity of the TCR, and it can be transiently or permanently expressed on T cells, regardless of the MHC restriction of the TCR or the presence of conventional coreceptors. Together, these observations indicate that CD8alphaalpha on T cells marks a differentiation stage and that it likely functions as a TCR corepressor to negatively regulate T cell activation.
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36
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Gangadharan D, Lambolez F, Attinger A, Wang-Zhu Y, Sullivan BA, Cheroutre H. Identification of pre- and postselection TCRalphabeta+ intraepithelial lymphocyte precursors in the thymus. Immunity 2006; 25:631-41. [PMID: 17045820 DOI: 10.1016/j.immuni.2006.08.018] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Revised: 07/17/2006] [Accepted: 08/14/2006] [Indexed: 12/23/2022]
Abstract
The immune system preserves and makes use of autoreactive lymphocytes with specialized functions. Here we showed that one of these populations, CD8alphaalpha(+)TCRalphabeta(+) intestinal intraepithelial lymphocytes (IELs), arose from a unique subset of double-positive thymocytes. This subset of cells was precommitted to preferentially give rise to CD8alphaalpha(+)TCRalphabeta(+) IELs, but they required exposure to self-agonist peptides. The agonist-selected TCRalphabeta(+) thymocytes are CD4 and CD8 double-negative, and their final maturation, including the induction of CD8alphaalpha expression, appeared to occur only after thymus export in the IL-15-rich environment of the gut. These developmental steps, including precommitment of immature thymocytes, TCR-mediated agonist selection, and postthymic differentiation promoted by cytokines, define a unique pathway for the generation of CD8alphaalpha(+)TCRalphabeta(+) IEL.
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Affiliation(s)
- Denise Gangadharan
- La Jolla Institute for Allergy and Immunology, 9420 Athena Circle, La Jolla, California 92037, USA
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37
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Bilic I, Ellmeier W. The role of BTB domain-containing zinc finger proteins in T cell development and function. Immunol Lett 2006; 108:1-9. [PMID: 17084908 DOI: 10.1016/j.imlet.2006.09.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2006] [Revised: 09/26/2006] [Accepted: 09/28/2006] [Indexed: 10/24/2022]
Abstract
Cell fate specifications during T lymphocyte differentiation result from the orchestrated expression of developmentally regulated genes. Furthermore, epigenetic processes that result in a heritable chromatin structure are required for the maintenance of gene expression programs within cells. More and more is known about the basic mechanisms of T cell development and their diversification into various peripheral T cell subsets. Recent research has begun to provide insight into the interactive network of transcription factors as critical regulators of T lymphocyte differentiation. In the past years several members of the BTB domain-containing family of zinc finger proteins (BTB-ZF) have been described to be important for the development and function of hematopoietic cells, and also to contribute to malignant hematopoiesis. This review will provide a brief overview about the role of BTB-ZF proteins during thymocyte development and T cell function.
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Affiliation(s)
- Ivan Bilic
- Institute of Immunology, Medical University of Vienna, Lazarettgasse 19, A-1090 Vienna, Austria
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38
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Bilic I, Koesters C, Unger B, Sekimata M, Hertweck A, Maschek R, Wilson CB, Ellmeier W. Negative regulation of CD8 expression via Cd8 enhancer-mediated recruitment of the zinc finger protein MAZR. Nat Immunol 2006; 7:392-400. [PMID: 16491076 PMCID: PMC3001192 DOI: 10.1038/ni1311] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2005] [Accepted: 01/17/2006] [Indexed: 01/22/2023]
Abstract
Coreceptor expression is tightly regulated during thymocyte development. Deletion of specific Cd8 enhancers leads to variegated expression of CD8alphabeta heterodimers in double-positive thymocytes. Here we show CD8 variegation is correlated with an epigenetic 'off' state, linking Cd8 enhancer function with chromatin remodeling of the adjacent genes Cd8a and Cd8b1 (Cd8). The zinc finger protein MAZR bound the Cd8 enhancer and interacted with the nuclear receptor corepressor N-CoR complex in double-negative thymocytes. MAZR was downregulated in double-positive and CD8 single-positive thymocytes. 'Enforced' expression of MAZR led to impaired Cd8 activation and variegated CD8 expression. Our results demonstrate epigenetic control of the Cd8 loci and identify MAZR as an important regulator of Cd8 expression.
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Affiliation(s)
- Ivan Bilic
- Institute of Immunology, Medical University of Vienna, Vienna 1090, Austria
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39
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Abstract
The mechanism of CD4-CD8 lineage commitment, which ensures the correlation between T cell receptor specificity and adoption of the T killer or T helper phenotype, has long been the subject of intense debate. Various approaches are slowly elucidating the underlying molecular pathways. Analysis of the function of T cell receptor signaling (the 'top-down' approach) supports the view that differences in signal strength and/or duration 'instruct' alternative commitment. Analysis of the transcriptional regulation of the genes encoding CD4 and CD8 (the 'bottom-up' approach) has identified critical cis-acting elements and their interacting factors. Finally, identification of the transcription factor Th-POK as a central component of the CD4 lineage-determining pathway has provided a new starting point from which to unravel this intriguing process 'from the inside out'.
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40
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Nie H, Maika SD, Tucker PW, Gottlieb PD. A Role for SATB1, a Nuclear Matrix Association Region-Binding Protein, in the Development of CD8SP Thymocytes and Peripheral T Lymphocytes. THE JOURNAL OF IMMUNOLOGY 2005; 174:4745-52. [PMID: 15814699 DOI: 10.4049/jimmunol.174.8.4745] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Studies have suggested that binding of the SATB1 protein to L2a, a matrix association region located 4.5 kb 5' to the mouse CD8alpha gene, positively affects CD8 expression in T cells. Therefore, experiments were performed to determine the effect on T cell development of reduced expression of SATB1. Because homozygous SATB1-null mice do not survive to adulthood due to non-thymus autonomous defects, mice were produced that were homozygous for a T cell-specific SATB1-antisense transgene and heterozygous for a SATB1-null allele. Thymic SATB1 protein was reduced significantly in these mice, and the major cellular phenotype observed was a significant reduction in the percentage of CD8SP T cells in thymus, spleen, and lymph nodes. Mice were smaller than wild type but generally healthy, and besides a general reduction in cellularity and a slight increase in surface CD3 expression on CD8SP thymocytes, the composition of the thymus was similar to wild type. The reduction in thymic SATB1 does not lead to the variegated expression of CD8-negative single positive thymocytes seen upon deletion of several regulatory elements and suggested by others to reflect failure to activate the CD8 locus. Thus, the present results point to an essential role for SATB1 late in the development and maturation of CD8SP T cells.
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Affiliation(s)
- Hui Nie
- Section of Molecular Genetics and Microbiology and Institute for Cellular and Molecular Biology, University of Texas, Austin, TX 78712, USA
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41
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Sato T, Ohno SI, Hayashi T, Sato C, Kohu K, Satake M, Habu S. Dual Functions of Runx Proteins for Reactivating CD8 and Silencing CD4 at the Commitment Process into CD8 Thymocytes. Immunity 2005; 22:317-28. [PMID: 15780989 DOI: 10.1016/j.immuni.2005.01.012] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2004] [Revised: 01/24/2005] [Accepted: 01/26/2005] [Indexed: 11/19/2022]
Abstract
To understand how CD8 expression is regulated during the transition process from CD4+8+ (CD4 and CD8 double positive, DP) to CD4-8+ (CD8 single positive, CD8SP) cells in the thymus, the involvement of Runx proteins in the alteration of chromatin configuration was investigated. Using the chromatin immunoprecipitation assay, we first demonstrated that Runx proteins bind to the stage-specific CD8 enhancer, as well as the CD4 silencer, in CD8SP thymocytes. Among Runx family members, Runx3 expression was initiated in DP thymocytes receiving a positive selection signal and increased in concert with differentiation to the CD8SP stage. Furthermore, reactivation of the CD8 gene, as well as CD4 silencing, was suppressed in positively selected thymocytes of Runx dominant-negative transgenic mice. These results suggest that Runx proteins, especially Runx3, are involved in lineage specification of CD8 T cells and provide important information for understanding the mechanism for the mutually exclusive expression of coreceptors in mature thymocytes.
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Affiliation(s)
- Takehito Sato
- Department of Immunology, Tokai University School of Medicine, Boseidai, Isehara, Kanagawa 259-1193, Japan
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42
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Feik N, Bilic I, Tinhofer J, Unger B, Littman DR, Ellmeier W. Functional and Molecular Analysis of the Double-Positive Stage-Specific CD8 Enhancer E8III during Thymocyte Development. THE JOURNAL OF IMMUNOLOGY 2005; 174:1513-24. [PMID: 15661911 DOI: 10.4049/jimmunol.174.3.1513] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Several developmental stage-, subset-, and lineage-specific Cd8 cis-regulatory regions have been identified. These include the E8(III) enhancer, which directs expression in double-positive (DP) thymocytes, and E8(II), which is active in DP cells and CD8(+) T cells. Using a transgenic reporter expression assay, we identified a 285-bp core fragment of the E8(III) enhancer that retains activity in DP thymocytes. In vitro characterization of the core enhancer revealed five regulatory elements that are required for full enhancer activity, suggesting that multiple factors contribute to the developmental stage-specific activity. Furthermore, deletion of E8(III) in the mouse germline showed that this enhancer is required for nonvariegated expression of CD8 in DP thymocytes when E8(II) is also deleted. These results indicate that E8(III) is one of the cis-elements that contribute to the activation of the Cd8a and Cd8b gene complex during T cell development.
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Affiliation(s)
- Nicholas Feik
- Institute of Immunology, Medical University Vienna, Vienna, Austria
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Ronai D, Berru M, Shulman MJ. The epigenetic stability of the locus control region-deficient IgH locus in mouse hybridoma cells is a clonally varying, heritable feature. Genetics 2005; 167:411-21. [PMID: 15166165 PMCID: PMC1470874 DOI: 10.1534/genetics.167.1.411] [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: 01/22/2023] Open
Abstract
Cis-acting elements such as enhancers and locus control regions (LCRs) prevent silencing of gene expression. We have shown previously that targeted deletion of an LCR in the immunoglobulin heavy-chain (IgH) locus creates conditions in which the immunoglobulin micro heavy chain gene can exist in either of two epigenetically inherited states, one in which micro expression is positive and one in which micro expression is negative, and that the positive and negative states are maintained by a cis-acting mechanism. As described here, the stability of these states, i.e., the propensity of a cell to switch from one state to the other, varied among subclones and was an inherited, clonal feature. A similar variation in stability was seen for IgH loci that both lacked and retained the matrix attachment regions associated with the LCR. Our analysis of cell hybrids formed by fusing cells in which the micro expression had different stabilities indicated that stability was also determined by a cis-acting feature of the IgH locus. Our results thus show that a single-copy gene in the same chromosomal location and in the presence of the same transcription factors can exist in many different states of expression.
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Affiliation(s)
- Diana Ronai
- Immunology Department, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
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Bosselut R. CD4/CD8-lineage differentiation in the thymus: from nuclear effectors to membrane signals. Nat Rev Immunol 2004; 4:529-40. [PMID: 15229472 DOI: 10.1038/nri1392] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Rémy Bosselut
- Laboratory of Immune Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
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Nardone J, Lee DU, Ansel KM, Rao A. Bioinformatics for the 'bench biologist': how to find regulatory regions in genomic DNA. Nat Immunol 2004; 5:768-74. [PMID: 15282556 DOI: 10.1038/ni0804-768] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The combination of bioinformatic and biological approaches constitutes a powerful method for identifying gene regulatory elements. High-quality genome sequences are available in public databases for several vertebrate species. Comparative cross-species sequence analysis of these genomes shows considerable conservation of noncoding sequences in DNA. Biological analyses show that an unexpectedly high number of the conserved sequences correspond to functional cis-regulatory regions that influence gene transcription. Because research biologists are often unfamiliar with the bioinformatic resources at their disposal, this commentary discusses how to integrate biological and bioinformatic methods in the discovery of gene regulatory regions and includes a tutorial on widely available comparative genomics programs.
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Affiliation(s)
- Julie Nardone
- Department of Pathology, Harvard Medical School and the CBR Institute for Biomedical Research, Boston, Massachusetts 02115, USA
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Abstract
Runx family proteins have the potential for either activating or suppressing gene expression in a context-dependent manner. There are several mechanisms by which transcriptional repression can occur. A wide range of locus inactivation, that is often called gene silencing, is thought to be achieved by chromatin modifications. Recently, Runx family proteins were found to have an essential role in either temporal transcriptional repression or irreversible epigenetic silencing at the CD4 locus through binding to a CD4 silencer at different stages of development. These findings link Runx function to epigenetic gene regulation, and shed new light on the mechanisms by which Runx represses target gene expression.
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Affiliation(s)
- Ichiro Taniuchi
- Laboratory for Transcriptional Regulation, RIKEN Research Center for Allergy and Immunology, Yokohama 230-0045, Japan.
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Gangadharan D, Cheroutre H. The CD8 isoform CD8αα is not a functional homologue of the TCR co-receptor CD8αβ. Curr Opin Immunol 2004; 16:264-70. [PMID: 15134773 DOI: 10.1016/j.coi.2004.03.015] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although structurally similar, CD8alphabeta and CD8alphaalpha have notably diverted with regard to function. Whereas CD8alphabeta functions as a T-cell receptor (TCR) co-receptor on MHC-class-I-restricted thymocytes and mature T cells, CD8alphaalpha is unable to support conventional positive selection, and can be expressed on T cells independent of the MHC restriction of their TCR. CD8alphaalpha induction is consistent with antigenic stimulation through the TCR, and recent developments have now shown that CD8alphaalpha induced on agonist-triggered immature thymocytes, antigenic-stimulated conventional CD8alphabeta T cells and mucosal T cells mediates the specific modulation of TCR activation signals to facilitate their survival and differentiation into various specialized T-cell subsets.
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Affiliation(s)
- Denise Gangadharan
- Division of Developmental Immunology, La Jolla Institute for Allergy & Immunology, 10355 Science Center Drive, San Diego, California 92121, USA
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Taniuchi I, Ellmeier W, Littman DR. The CD4/CD8 lineage choice: new insights into epigenetic regulation during T cell development. Adv Immunol 2004; 83:55-89. [PMID: 15135628 DOI: 10.1016/s0065-2776(04)83002-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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von Boehmer H. Selection of the T-Cell Repertoire: Receptor-Controlled Checkpoints in T-Cell Development. Adv Immunol 2004; 84:201-38. [PMID: 15246254 DOI: 10.1016/s0065-2776(04)84006-9] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Harald von Boehmer
- Harvard Medical School, Dana-Farber Cancer Institute, Boston, Massachusetts USA
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Barthel R, Goldfeld AE. T Cell-Specific Expression of the Human TNF-α Gene Involves a Functional and Highly Conserved Chromatin Signature in Intron 3. THE JOURNAL OF IMMUNOLOGY 2003; 171:3612-9. [PMID: 14500658 DOI: 10.4049/jimmunol.171.7.3612] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Using a phylogenetic approach, we identified highly conserved sequences within intron 3 of the human TNF-alpha gene. These sequences form cell type-specific DNase I hypersensitivity sites and display cell type-specific DNA-protein contacts in in vivo genomic footprints. Consistent with these results, intron 3 confers specific activity upon a TNF-alpha reporter gene in Jurkat T cells, but not THP-1 monocytic cells. Thus, using a combinatorial approach of phylogenetic analysis, DNase I hypersensitivity analysis, in vivo footprinting, and transfection analysis, we demonstrate that intronic regulatory elements are involved in the cell type-specific regulation of TNF-alpha gene expression.
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Affiliation(s)
- Robert Barthel
- Center for Blood Research and Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
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