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Perico L, Casiraghi F, Sônego F, Todeschini M, Corna D, Cerullo D, Pezzotta A, Isnard-Petit P, Faravelli S, Forneris F, Thiam K, Benigni A, Remuzzi G. Bi-specific autoantigen-T cell engagers as targeted immunotherapy for autoreactive B cell depletion in autoimmune diseases. Front Immunol 2024; 15:1335998. [PMID: 38469301 PMCID: PMC10926275 DOI: 10.3389/fimmu.2024.1335998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 02/07/2024] [Indexed: 03/13/2024] Open
Abstract
Introduction In autoimmune diseases, autoreactive B cells comprise only the 0.1-0.5% of total circulating B cells. However, current first-line treatments rely on non-specific and general suppression of the immune system, exposing patients to severe side effects. For this reason, identification of targeted therapies for autoimmune diseases is an unmet clinical need. Methods Here, we designed a novel class of immunotherapeutic molecules, Bi-specific AutoAntigen-T cell Engagers (BiAATEs), as a potential approach for targeting the small subset of autoreactive B cells. To test this approach, we focused on a prototype autoimmune disease of the kidney, membranous nephropathy (MN), in which phospholipase A2 receptor (PLA2R) serves as primary nephritogenic antigen. Specifically, we developed a BiAATE consisting of the immunodominant Cysteine-Rich (CysR) domain of PLA2R and the single-chain variable fragment (scFv) of an antibody against the T cell antigen CD3, connected by a small flexible linker. Results BiAATE creates an immunological synapse between autoreactive B cells bearing an CysR-specific surface Ig+ and T cells. Ex vivo, the BiAATE successfully induced T cell-dependent depletion of PLA2R-specific B cells isolated form MN patients, sparing normal B cells. Systemic administration of BiAATE to mice transgenic for human CD3 reduced anti-PLA2R antibody levels following active immunization with PLA2R. Discussion Should this approach be confirmed for other autoimmune diseases, BiAATEs could represent a promising off-the-shelf therapy for precision medicine in virtually all antibody-mediated autoimmune diseases for which the pathogenic autoantigen is known, leading to a paradigm shift in the treatment of these diseases.
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Affiliation(s)
- Luca Perico
- Department of Molecular Medicine, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Federica Casiraghi
- Department of Molecular Medicine, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | | | - Marta Todeschini
- Department of Molecular Medicine, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Daniela Corna
- Department of Molecular Medicine, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Domenico Cerullo
- Department of Molecular Medicine, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Anna Pezzotta
- Department of Molecular Medicine, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | | | - Silvia Faravelli
- The Armenise-Harvard Laboratory of Structural Biology, Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Federico Forneris
- The Armenise-Harvard Laboratory of Structural Biology, Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Kader Thiam
- Preclinical Models & Services, genOway, Lyon, France
| | - Ariela Benigni
- Department of Molecular Medicine, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Giuseppe Remuzzi
- Department of Molecular Medicine, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
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Abstract
Historically, the immune system was believed to develop along a linear axis of maturity from fetal life to adulthood. Now, it is clear that distinct layers of immune cells are generated from unique waves of hematopoietic progenitors during different windows of development. This model, known as the layered immune model, has provided a useful framework for understanding why distinct lineages of B cells and γδ T cells arise in succession and display unique functions in adulthood. However, the layered immune model has not been applied to CD8+ T cells, which are still often viewed as a uniform population of cells belonging to the same lineage, with functional differences between cells arising from environmental factors encountered during infection. Recent studies have challenged this idea, demonstrating that not all CD8+ T cells are created equally and that the functions of individual CD8+ T cells in adults are linked to when they were created in the host. In this review, we discuss the accumulating evidence suggesting there are distinct ontogenetic subpopulations of CD8+ T cells and propose that the layered immune model be extended to the CD8+ T cell compartment.
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Affiliation(s)
- Cybelle Tabilas
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
- Co-first author
| | - Norah L. Smith
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
- Co-first author
| | - Brian D. Rudd
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
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3
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Kim S, Shukla RK, Yu H, Baek A, Cressman SG, Golconda S, Lee GE, Choi H, Reneau JC, Wang Z, Huang CA, Liyanage NPM, Kim S. CD3e-immunotoxin spares CD62L lo Tregs and reshapes organ-specific T-cell composition by preferentially depleting CD3e hi T cells. Front Immunol 2022; 13:1011190. [PMID: 36389741 PMCID: PMC9643874 DOI: 10.3389/fimmu.2022.1011190] [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: 08/03/2022] [Accepted: 10/04/2022] [Indexed: 02/03/2023] Open
Abstract
CD3-epsilon(CD3e) immunotoxins (IT), a promising precision reagent for various clinical conditions requiring effective depletion of T cells, often shows limited treatment efficacy for largely unknown reasons. Tissue-resident T cells that persist in peripheral tissues have been shown to play pivotal roles in local and systemic immunity, as well as transplant rejection, autoimmunity and cancers. The impact of CD3e-IT treatment on these local cells, however, remains poorly understood. Here, using a new murine testing model, we demonstrate a substantial enrichment of tissue-resident Foxp3+ Tregs following CD3e-IT treatment. Differential surface expression of CD3e among T-cell subsets appears to be a main driver of Treg enrichment in CD3e-IT treatment. The surviving Tregs in CD3e-IT-treated mice were mostly the CD3edimCD62Llo effector phenotype, but the levels of this phenotype markedly varied among different lymphoid and nonlymphoid organs. We also found notable variations in surface CD3e levels among tissue-resident T cells of different organs, and these variations drive CD3e-IT to uniquely reshape T-cell compositions in local organs. The functions of organs and anatomic locations (lymph nodes) also affected the efficacy of CD3e-IT. The multi-organ pharmacodynamics of CD3e-IT and potential treatment resistance mechanisms identified in this study may generate new opportunities to further improve this promising treatment.
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Affiliation(s)
- Shihyoung Kim
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - Rajni Kant Shukla
- Department of Microbial Immunity and Infection, The Ohio State University, Columbus, OH, United States
| | - Hannah Yu
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - Alice Baek
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - Sophie G. Cressman
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - Sarah Golconda
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - Ga-Eun Lee
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - Hyewon Choi
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States
| | - John C. Reneau
- Division of Hematology, The Ohio State University, Columbus, OH, United States
| | - Zhirui Wang
- Department of Surgery, University of Colorado Denver Anschutz Medical Campus, Aurora, CO, United States
| | - Christene A. Huang
- Department of Surgery, University of Colorado Denver Anschutz Medical Campus, Aurora, CO, United States
| | - Namal P. M. Liyanage
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States,Department of Microbial Immunity and Infection, The Ohio State University, Columbus, OH, United States,Infectious Disease Institute, The Ohio State University, Columbus, OH, United States,*Correspondence: Namal P. M. Liyanage, ; Sanggu Kim,
| | - Sanggu Kim
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH, United States,Infectious Disease Institute, The Ohio State University, Columbus, OH, United States,*Correspondence: Namal P. M. Liyanage, ; Sanggu Kim,
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4
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Xue G, Zippelius A, Wicki A, Mandala M, Tang F, Massi D, Hemmings BA. Integrated Akt/PKB Signaling in Immunomodulation and Its Potential Role in Cancer Immunotherapy. J Natl Cancer Inst 2015; 107:djv171. [DOI: 10.1093/jnci/djv171] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 05/22/2015] [Indexed: 12/17/2022] Open
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5
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6
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del Blanco B, García-Mariscal A, Wiest DL, Hernández-Munain C. Tcra enhancer activation by inducible transcription factors downstream of pre-TCR signaling. THE JOURNAL OF IMMUNOLOGY 2012; 188:3278-93. [PMID: 22357628 DOI: 10.4049/jimmunol.1100271] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The Tcra enhancer (Eα) is essential for pre-TCR-mediated activation of germline transcription and V(D)J recombination. Eα is considered an archetypical enhanceosome that acts through the functional synergy and cooperative binding of multiple transcription factors. Based on dimethylsulfate genomic footprinting experiments, there has been a long-standing paradox regarding Eα activation in the absence of differences in enhancer occupancy. Our data provide the molecular mechanism of Eα activation and an explanation of this paradox. We found that germline transcriptional activation of Tcra is dependent on constant phospholipase Cγ, as well as calcineurin- and MAPK/ERK-mediated signaling, indicating that inducible transcription factors are crucially involved. NFAT, AP-1, and early growth response factor 1, together with CREB-binding protein/p300 coactivators, bind to Eα as part of an active enhanceosome assembled during pre-TCR signaling. We favor a scenario in which the binding of lymphoid-restricted and constitutive transcription factors to Eα prior to its activation forms a regulatory scaffold to recruit factors induced by pre-TCR signaling. Thus, the combinatorial assembly of tissue- and signal-specific transcription factors dictates the Eα function. This mechanism for enhancer activation may represent a general paradigm in tissue-restricted and stimulus-responsive gene regulation.
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Affiliation(s)
- Beatriz del Blanco
- Departamento de Biología Celular e Inmunología, Instituto de Parasitología y Biomedicina López-Neyra (IPBLN-CSIC), Consejo Superior de Investigaciones Científicas, 18100-Armilla, Granada, Spain
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7
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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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8
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Juntilla MM, Koretzky GA. Critical roles of the PI3K/Akt signaling pathway in T cell development. Immunol Lett 2008; 116:104-10. [PMID: 18243340 PMCID: PMC2322870 DOI: 10.1016/j.imlet.2007.12.008] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Revised: 12/11/2007] [Accepted: 12/12/2007] [Indexed: 11/26/2022]
Abstract
Thymocyte development requires an integration of extracellular cues to enforce lineage commitment at multiple defined checkpoints in a stage-specific manner. Critical signals from the pre-TCR, Notch, and the receptor for interleukin-7 (IL-7) dictate cellular differentiation from the CD4(-)CD8(-) (double negative) stage to the CD4+CD8+ (double positive) stage. The PI3K/Akt signaling pathway is required to translate these extracellular signaling events into multiple functional outcomes including cellular survival, proliferation, differentiation, and allelic exclusion at the beta-selection checkpoint. However, a complete understanding of the contributions made by the PI3K/Akt pathway in thymocyte development has not been straightforward. This review highlights studies that support the model that the PI3K/Akt pathway is essential for thymocyte survival. We provide new evidence that Akt-mediated survival is not solely due to the increased expression of Bcl-xL but also is a consequence of the role played by Akt to support metabolism in proliferating thymocytes.
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Affiliation(s)
- Marisa M Juntilla
- Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6160, USA
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9
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Gu JJ, Zhang N, He YW, Koleske AJ, Pendergast AM. Defective T cell development and function in the absence of Abelson kinases. THE JOURNAL OF IMMUNOLOGY 2008; 179:7334-43. [PMID: 18025176 DOI: 10.4049/jimmunol.179.11.7334] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Thymocyte proliferation, survival, and differentiation are tightly controlled by signaling from the pre-TCR. In this study, we show for the first time that the Abelson (Abl) kinases regulate proximal signaling downstream of the pre-TCR. Conditional deletion of Abl kinases in thymocytes reveals a cell-autonomous role for these proteins in T cell development. The conditional knockout mice have reduced numbers of thymocytes, exhibit an increase in the percentage of the CD4(-)CD8(-) double-negative population, and are partially blocked in the transition to the CD4(+)CD8(+) double-positive stage. Moreover, the total number of T cells is greatly reduced in the Abl mutant mice, and the null T cells exhibit impaired TCR-induced signaling, proliferation, and cytokine production. Notably, Abl mutant mice are compromised in their ability to produce IFN-positive CD8 T cells and exhibit impaired CD8(+) T cell expansion in vivo upon Listeria monocytogenes infection. Furthermore, Ab production in response to T cell-dependent Ag is severely impaired in the Abl mutant mice. Together these findings reveal cell-autonomous roles for the Abl family kinases in both T cell development and mature T cell function, and show that loss of these kinases specifically in T cells results in compromised immunity.
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Affiliation(s)
- Jing Jin Gu
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
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10
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Joachims ML, Chain JL, Hooker SW, Knott-Craig CJ, Thompson LF. Human alpha beta and gamma delta thymocyte development: TCR gene rearrangements, intracellular TCR beta expression, and gamma delta developmental potential--differences between men and mice. THE JOURNAL OF IMMUNOLOGY 2006; 176:1543-52. [PMID: 16424183 PMCID: PMC1592528 DOI: 10.4049/jimmunol.176.3.1543] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To evaluate the role of the TCR in the alphabeta/gammadelta lineage choice during human thymocyte development, molecular analyses of the TCRbeta locus in gammadelta cells and the TCRgamma and delta loci in alphabeta cells were undertaken. TCRbeta variable gene segments remained largely in germline configuration in gammadelta cells, indicating that commitment to the gammadelta lineage occurred before complete TCRbeta rearrangements in most cases. The few TCRbeta rearrangements detected were primarily out-of-frame, suggesting that productive TCRbeta rearrangements diverted cells away from the gammadelta lineage. In contrast, in alphabeta cells, the TCRgamma locus was almost completely rearranged with a random productivity profile; the TCRdelta locus contained primarily nonproductive rearrangements. Productive gamma rearrangements were, however, depleted compared with preselected cells. Productive TCRgamma and delta rearrangements rarely occurred in the same cell, suggesting that alphabeta cells developed from cells unable to produce a functional gammadelta TCR. Intracellular TCRbeta expression correlated with the up-regulation of CD4 and concomitant down-regulation of CD34, and plateaued at the early double positive stage. Surprisingly, however, some early double positive thymocytes retained gammadelta potential in culture. We present a model for human thymopoiesis which includes gammadelta development as a default pathway, an instructional role for the TCR in the alphabeta/gammadelta lineage choice, and a prolonged developmental window for beta selection and gammadelta lineage commitment. Aspects that differ from the mouse are the status of TCR gene rearrangements at the nonexpressed loci, the timing of beta selection, and maintenance of gammadelta potential through the early double positive stage of development.
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MESH Headings
- Animals
- Cell Cycle/genetics
- Cell Cycle/immunology
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Cell Lineage/genetics
- Cell Lineage/immunology
- Child
- Coculture Techniques
- Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor
- Gene Rearrangement, beta-Chain T-Cell Antigen Receptor
- Gene Rearrangement, delta-Chain T-Cell Antigen Receptor
- Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor
- Humans
- Infant
- Intracellular Fluid/immunology
- Intracellular Fluid/metabolism
- Mice
- Models, Immunological
- Organ Culture Techniques
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/biosynthesis
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Thymus Gland/cytology
- Thymus Gland/immunology
- Thymus Gland/metabolism
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Affiliation(s)
- Michelle L. Joachims
- Immunobiology and Cancer Program Oklahoma Medical Research Foundation 825 NE 13 St. Oklahoma City, OK 73104
| | - Jennifer L. Chain
- Immunobiology and Cancer Program Oklahoma Medical Research Foundation 825 NE 13 St. Oklahoma City, OK 73104
- Department of Microbiology and
| | - Scott W. Hooker
- Immunobiology and Cancer Program Oklahoma Medical Research Foundation 825 NE 13 St. Oklahoma City, OK 73104
| | | | - Linda F. Thompson
- Immunobiology and Cancer Program Oklahoma Medical Research Foundation 825 NE 13 St. Oklahoma City, OK 73104
- Department of Microbiology and
- Address correspondence and reprint requests to Dr. Linda F. Thompson, Oklahoma Medical Research Foundation, 825 NE 13 St., Oklahoma City, OK 73104. Phone: (405) 271-7235; FAX:(405) 271-7128. E-mail address:
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11
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Grady GC, Mason SM, Stephen J, Zúñiga-Pflücker JC, Michie AM. Cyclic adenosine 5'-monophosphate response element binding protein plays a central role in mediating proliferation and differentiation downstream of the pre-TCR complex in developing thymocytes. THE JOURNAL OF IMMUNOLOGY 2004; 173:1802-10. [PMID: 15265911 DOI: 10.4049/jimmunol.173.3.1802] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The roles played by specific transcription factors during the regulation of early T cell development remain largely undefined. Several key genes induced during the primary checkpoint of T cell development, beta-selection, contain cAMP response element sites within their enhancer-promoter region that are regulated by CREB activation. In this study, we show that CREB is constitutively phosphorylated in the thymus, but not the spleen. We also show that CREB is activated downstream of the pre-TCR complex, and that the induction of CREB activity is regulated by protein kinase C alpha- and ERK-MAPK-mediated signals. We addressed the importance of this activation by expressing a naturally occurring inhibitor of CREB, inducible cAMP early repressor in wild-type fetal liver-derived lymphoid progenitor cells, and assessed their developmental potential. Fetal thymic organ cultures reconstituted with cells constitutively expressing inducible cAMP early repressor displayed a delay in generating CD4(+)CD8(+) thymocytes and a decrease in cellularity compared with control fetal thymic organ cultures. Taken together, our studies establish that CREB plays a central role in relaying proliferation and differentiation signals from the pre-TCR complex into the nucleus in developing thymocytes.
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Affiliation(s)
- Gillian C Grady
- Division of Immunology, Infection, and Inflammation, University of Glasgow, Glasgow, Scotland, United Kingdom
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12
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Yui MA, Rothenberg EV. Deranged Early T Cell Development in Immunodeficient Strains of Nonobese Diabetic Mice. THE JOURNAL OF IMMUNOLOGY 2004; 173:5381-91. [PMID: 15494484 DOI: 10.4049/jimmunol.173.9.5381] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
NOD mice exhibit defects in T cell functions that have been postulated to contribute to diabetes susceptibility in this strain. However, early T cell development in NOD mice has been largely unexplored. NOD mice with the scid mutation and Rag1 deficiency were analyzed for pre-T cell development in the NOD genetic background. These strains reveal an age-dependent, programmed breakdown in beta selection checkpoint enforcement. At 5-8 wk of age, even in the absence of TCRbeta expression, CD4+ and CD4+CD8+ blasts appear spontaneously. However, these breakthrough cells fail to restore normal thymic cellularity. The breakthrough phenotype is recessive in hybrid (NODxB6)F1-scid and -Rag1null mice. The breakthrough cells show a mosaic phenotype with respect to components of the beta selection program. They mimic normal beta selection by up-regulating germline TCR-Calpha transcripts, CD2, and Bcl-xL and down-regulating Bcl-2. However, they fail to down-regulate transcription factors HEB-alt and Hes1 and initially express aberrantly high levels of Spi-B, c-kit (CD117), and IL-7Ralpha. Other genes examined distinguish this form of breakthrough from previously reported models. Some of the abnormalities appear first in a cohort of postnatal thymocytes as early as the double-negative 2/double-negative 3 transitional stage. Thus, our results reveal an NOD genetic defect in T cell developmental programming and checkpoint control that permits a subset of the normal outcomes of pre-TCR signaling to proceed even in the absence of TCRbeta rearrangement. Furthermore, this breakthrough may initiate thymic lymphomagenesis that occurs with high frequency in both NOD-scid and -Rag1null mice.
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MESH Headings
- Aging/genetics
- Aging/immunology
- Animals
- CD2 Antigens/biosynthesis
- CD2 Antigens/genetics
- CD4 Antigens/biosynthesis
- Cell Cycle/genetics
- Cell Cycle/immunology
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Cell Division/genetics
- Cell Division/immunology
- Gene Expression Regulation/immunology
- Genes, RAG-1
- Genes, Recessive
- Genes, T-Cell Receptor alpha
- Lymphopenia/genetics
- Lymphopenia/immunology
- Lymphopenia/pathology
- Mice
- Mice, Inbred C57BL
- Mice, Inbred NOD
- Mice, Knockout
- Mice, SCID
- Mice, Transgenic
- Proto-Oncogene Proteins c-bcl-2/antagonists & inhibitors
- Proto-Oncogene Proteins c-bcl-2/biosynthesis
- Proto-Oncogene Proteins c-kit/biosynthesis
- Receptors, Interleukin-7/biosynthesis
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/pathology
- Thymus Gland/immunology
- Thymus Gland/metabolism
- Thymus Gland/pathology
- Transcription, Genetic
- Up-Regulation/immunology
- bcl-X Protein
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Affiliation(s)
- Mary A Yui
- Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA
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Krotkova A, Smith E, Nerz G, Falk I, Eichmann K. Delayed and restricted expression limits putative instructional opportunities of Vgamma1.1/Vgamma2 gammadelta TCR in alphabeta/gammadelta lineage choice in the thymus. THE JOURNAL OF IMMUNOLOGY 2004; 173:25-32. [PMID: 15210755 DOI: 10.4049/jimmunol.173.1.25] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Development of alphabeta and gammadelta T cells depends on productive rearrangement of the appropriate TCR genes and their subsequent expression as proteins. TCRbeta and TCRgammadelta proteins first appear in DN3 and DN4 thymocytes, respectively. So far, it is not clear whether this is due to a delayed expression of TCRgammadelta proteins or to a more rapid progression to DN4 of thymocytes expressing TCRgammadelta. The answer to this question bears on the distinction between instructive and stochastic models of alphabeta/gammadelta lineage decision. To study this question, we first monitored initial TCR protein expression in wild-type and TCR transgenic mice in reaggregate thymic organ cultures. A TCRbeta transgene was expressed in nearly all DN3 and DN4 cells, accelerated DN3 to DN4 transition, and strongly diminished the number of cells that express TCRgammadelta proteins. In contrast, TCRgammadelta transgenes were expressed only in a fraction of DN4 cells, did not accelerate DN3 to DN4 transition, and did not reduce the number of DN4 cells expressing TCRbeta proteins. The TCRbeta transgene partially inhibited endogenous TCRgamma rearrangements, whereas the TCRgammadelta transgenes did not inhibit endogenous TCRbeta rearrangements. Second, we analyzed frequencies of productive TCRbeta and TCRgammadelta V(D)J junctions in DN3 and DN4 subsets. Most importantly, frequencies of productive TCRgammadelta rearrangements (Vdelta5, Vgamma1.1, and Vgamma2) appeared unselected in DN3. The results suggest a late and restricted expression of the corresponding gammadeltaTCR, severely limiting their putative instructional opportunities in alphabeta/gammadelta divergence.
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MESH Headings
- Animals
- Cell Lineage
- Gene Rearrangement, T-Lymphocyte
- Genes, T-Cell Receptor beta
- Lymphocyte Activation
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Receptors, Antigen, T-Cell, alpha-beta/physiology
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/physiology
- T-Lymphocytes/physiology
- Thymus Gland/immunology
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Affiliation(s)
- Anna Krotkova
- Max-Planck-Institut für Immunbiologie, Stübeweg 541, 79108 Freiburg, Germany
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Abstract
The specificity of the adaptive immune response is, in part, dependent on the clonal expression of the mature T cell receptor (TCR) on T lymphocytes. One mechanism regulating the clonality of the TCR occurs at the level of TCR-beta gene rearrangements during lymphocyte development. Expression of a nascent TCR-beta chain together with pre-Talpha (pTalpha) and CD3 molecules to form the pre-TCR complex, represents a critical checkpoint in T cell differentiation known as beta-selection. Indeed, failure to generate a functionally rearranged TCR-beta chain at this stage of development results in apoptosis. Signals derived from the pre-TCR complex trigger a maturation program within developing thymocytes that includes: rescue from apoptosis; inhibition of further DNA recombination at the TCR-beta gene locus (allowing for the clonality of antigen receptor expression; allelic exclusion); and induction of proliferation and differentiation. The signaling mechanisms that control this developmental program remain largely undefined. Here, we discuss recent evidence investigating the molecular mechanisms that regulate thymocyte differentiation downstream of pre-TCR formation.
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Affiliation(s)
- Alison M Michie
- Department of Immunology and Bacteriology, Western Infirmary, University of Glasgow, Glasgow, Scotland, G11 6NT, UK
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15
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Vasseur F, Le Campion A, Pénit C. Scheduled kinetics of cell proliferation and phenotypic changes during immature thymocyte generation. Eur J Immunol 2001; 31:3038-47. [PMID: 11592080 DOI: 10.1002/1521-4141(2001010)31:10<3038::aid-immu3038>3.0.co;2-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Precursor CD4-CD8- (DN) thymocytes rearrange their TCR-beta genes, and only those which succeed in beta-selection subsequently expand and differentiate into immature CD4+CD8+ (DP) thymocytes. The cell subsets corresponding to the successive steps of this transition can be defined in terms of CD44 and CD25 expression. We partially synchronized the differentiation process by eliminating cycling cells with the anti-mitotic agent demecolcine. Using in vivo pulse labeling with bromodeoxyuridine, we determined the order of entry into DNA synthesis of the different DN and transitory (CD4-/lo CD8+) cell subsets. Two independent proliferation phases were identified. The first cells to enter the cell cycle were CD44-CD25lo, and CD4/CD8/TCR-/BrdU four-color staining showed that they all expressed a low density of the TCR-beta chain, an element of the pre-TCR (the TCR-alpha locus is still in germ-line configuration at this stage). Cycling of CD44+CD25+ cells was detected later, and no starting point was observed at the CD44-CD25hi stage. CD8 expression was immediately detectable in cycling cells, but they took 24 h to reach the DP stage. The study of TCR-Calpha-deficient mice showed that beta gene rearrangement occurred once proliferation had ceased at the DP stage, and that it had no influence on the DN-DP transition. These data show that precursor thymocytes undergo two independent waves of expansion, and that the second wave is restricted to cells capable of pre-TCR expression.
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Affiliation(s)
- F Vasseur
- Institut National de la Santé et de la Recherche Médicale (INSERM) U 345, Institut Necker, Paris, France
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16
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Mongini C, Ruybal P, Gravisaco MJ, Croci M, Sánchez Lockhart M, Fabris V, Waldner AC. Characterization of the immunophenotype and the metastatic properties of a murine T-lymphoma cell line. Unexpected expression of cytoplasmatic CD4. In Vitro Cell Dev Biol Anim 2001; 37:499-504. [PMID: 11669283 DOI: 10.1290/1071-2690(2001)037<0499:cotiat>2.0.co;2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We report the first characterization of a mouse T-lymphoma cell line that surprisingly expresses cytoplasmatic (cy) yCD4. Phenotypically, LBC cells are CD5+, CD8+, CD16+, CD24+, CD25+, CD2-/dim, CD3-/dim, TCRbeta-/dim, TCRgammadelta, CD154 , CD40-, and CD45R. Coexpress cyTCRbeta, cyCD3, cyCD4, and yet lack surface CD4 expression. Transplantation of LBC cells into mice resulted in an aggressive T-lymphoblastic lymphoma that infiltrated lymph nodes, thymus, spleen, liver, ovary, and uterus but not peripheral blood or bone marrow. LBC cells display a modal chromosome number of 39 and a near-diploid karyotype. Based on the characterization data, we demonstrated that the LBC cell line was derived from an early T-cell lymphocyte precursor. We propose that the malignant cell transformation of LBC cells could coincide with the transition stage from late double-negative, DN3 (CD4- CD8 CD44-/low, CD25+) or DN4 (CD4-low, CD8-/low, CD44-, CD25-) to double-positive (DP: CD4+CD8+) stage of T-cell development. LBC cells provide a T-lymphoblastic lymphoma model derived from a malignant early T-lymphocyte that can be potentially useful as a model to study both cellular regulation and differentiation of T-cells. In addition, LBC tumor provides a short latency neoplasm to study cellular regulation and to perform preclinical trials of lymphoma-relatel clisorders.
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Affiliation(s)
- C Mongini
- Institut de Estudios de la Inmunidad Humoral, UBA-CONICET, Department of Immunology, School of Pharmacy and Biochemistry, University of Buenos Aires, Argentina.
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17
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Petersson K, Ivars F. Early TCR αβ Expression Promotes Maturation of T Cells Expressing FcεRIγ Containing TCR/CD3 Complexes. THE JOURNAL OF IMMUNOLOGY 2001; 166:6616-24. [PMID: 11359815 DOI: 10.4049/jimmunol.166.11.6616] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In a previous study we presented data indicating that the expanded population of CD4(-)CD8(-) (DN) alphabeta T cells in TCRalpha-chain-transgenic mice was partially if not entirely derived from gammadelta T cell lineage cells. The development of both gammadelta T cells and DN alphabeta T cells is poorly understood; therefore, we thought it would be important to identify the immediate precursors of the transgene-induced DN alphabeta T cells. We have in this report studied the early T cell development in these mice and we show that the transgenic TCRalpha-chain is expressed by precursor thymocytes already at the CD3(-)CD4(-)CD8(-) (triple negative, TN) CD44(+)CD25(-) stage of development. Both by using purified precursor populations in reconstitution experiments and by analyzing fetal thymocyte development, we demonstrated that early TN precursors expressing endogenous TCRbeta-chains matured into DN alphabeta T cells at several stages of development. The genes encoding the gamma-chain of the high affinity receptor for IgE (FcepsilonRIgamma) and the CD3zeta protein were found to be reciprocally expressed in TN thymocytes such that during development the FcepsilonRIgamma expression decreased whereas CD3zeta expression increased. Furthermore, in a fraction of the transgene-induced DN alphabeta T cells the FcepsilonRIgamma protein colocalized with the TCR/CD3 complex. These data suggest that similarly to gammadelta T cells and NKT cells, precursors expressing the TCR early in the common alphabetagammadelta developmental pathway may use the FcepsilonRIgamma protein as a signaling component of the TCR/CD3 complex.
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MESH Headings
- Animals
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Cell Lineage/genetics
- Cell Lineage/immunology
- Cells, Cultured
- Female
- Gene Expression Regulation/genetics
- Gene Expression Regulation/immunology
- Genes, T-Cell Receptor alpha/genetics
- Immunophenotyping
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Organ Culture Techniques
- Receptor-CD3 Complex, Antigen, T-Cell/metabolism
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/physiology
- Receptors, IgE/metabolism
- Stem Cells/cytology
- Stem Cells/immunology
- Stem Cells/metabolism
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- Thymus Gland/cytology
- Thymus Gland/growth & development
- Thymus Gland/immunology
- Thymus Gland/metabolism
- Tumor Cells, Cultured
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Affiliation(s)
- K Petersson
- Section for Immunology, Department of Cell and Molecular Biology, Lund University, Sölvegatan 19, SE 22362 Lund, Sweden
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18
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Aifantis I, Gounari F, Scorrano L, Borowski C, von Boehmer H. Constitutive pre-TCR signaling promotes differentiation through Ca2+ mobilization and activation of NF-kappaB and NFAT. Nat Immunol 2001; 2:403-9. [PMID: 11323693 DOI: 10.1038/87704] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Pre-T cell antigen receptor (pre-TCR) signaling plays a crucial role in the development of immature T cells. Although certain aspects of proximal pre-TCR signaling have been studied, the intermediate signal transducers and the distal transcription modulators have been poorly characterized. We report here a correlation between pre-TCR signaling and a biphasic rise in the cytosolic Ca2+ concentration. In addition, we show that constitutive pre-TCR signaling is associated with an increased rate of Ca2+ influx through store-operated plasma membrane Ca2+ channels. We show also that the biphasic nature of the observed pre-TCR-induced rise in cytosolic Ca2+ differentially modulates the activities of the transcription factors NF-kappaB and NFAT in developing T cells.
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Affiliation(s)
- I Aifantis
- Department of Pathology, Harvard Medical School, Dana-Farber Cancer Institute, Boston, MA 02115, USA
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19
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Yoder J, Pham C, Iizuka YM, Kanagawa O, Liu SK, McGlade J, Cheng AM. Requirement for the SLP-76 adaptor GADS in T cell development. Science 2001; 291:1987-91. [PMID: 11239162 DOI: 10.1126/science.1057176] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
GADS is an adaptor protein implicated in CD3 signaling because of its ability to link SLP-76 to LAT. A GADS-deficient mouse was generated by gene targeting, and the function of GADS in T cell development and activation was examined. GADS- CD4-CD8- thymocytes exhibited a severe block in proliferation but still differentiated into mature T cells. GADS- thymocytes failed to respond to CD3 cross-linking in vivo and were impaired in positive and negative selection. Immunoprecipitation experiments revealed that the association between SLP-76 and LAT was uncoupled in GADS- thymocytes. These observations indicate that GADS is a critical adaptor for CD3 signaling.
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Affiliation(s)
- J Yoder
- Medical Scientist Training Program, Washington University School of Medicine, St. Louis, MO 63110, USA
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20
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Thompson LF, Van de Wiele CJ, Laurent AB, Hooker SW, Vaughn JG, Jiang H, Khare K, Kellems RE, Blackburn MR, Hershfield MS, Resta R. Metabolites from apoptotic thymocytes inhibit thymopoiesis in adenosine deaminase-deficient fetal thymic organ cultures. J Clin Invest 2000; 106:1149-57. [PMID: 11067867 PMCID: PMC301416 DOI: 10.1172/jci9944] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2000] [Accepted: 09/25/2000] [Indexed: 01/03/2023] Open
Abstract
Murine fetal thymic organ culture was used to investigate the mechanism by which adenosine deaminase (ADA) deficiency causes T-cell immunodeficiency. C57BL/6 fetal thymuses treated with the specific ADA inhibitor 2'-deoxycoformycin exhibited features of the human disease, including accumulation of dATP and inhibition of S-adenosylhomocysteine hydrolase enzyme activity. Although T-cell receptor (TCR) Vbeta gene rearrangements and pre-TCR-alpha expression were normal in ADA-deficient cultures, the production of alphabeta TCR(+) thymocytes was inhibited by 95%, and differentiation was blocked beginning at the time of beta selection. In contrast, the production of gammadelta TCR(+) thymocytes was unaffected. Similar results were obtained using fetal thymuses from ADA gene-targeted mice. Differentiation and proliferation were preserved by the introduction of a bcl-2 transgene or disruption of the gene encoding apoptotic protease activating factor-1. The pan-caspase inhibitor carbobenzoxy-Val-Ala-Asp-fluoromethyl ketone also significantly lessened the effects of ADA deficiency and prevented the accumulation of dATP. Thus, ADA substrates accumulate and disrupt thymocyte development in ADA deficiency. These substrates derive from thymocytes that undergo apoptosis as a consequence of failing to pass developmental checkpoints, such as beta selection.
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MESH Headings
- Adenosine Deaminase/deficiency
- Adenosine Deaminase/genetics
- Animals
- Apoptosis
- Base Sequence
- DNA Primers/genetics
- Fetus/cytology
- Fetus/metabolism
- Hematopoiesis
- Humans
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Organ Culture Techniques
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Receptors, Antigen, T-Cell, gamma-delta/metabolism
- T-Lymphocytes/cytology
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
- Thymus Gland/cytology
- Thymus Gland/immunology
- Thymus Gland/metabolism
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Affiliation(s)
- L F Thompson
- Immunobiology and Cancer Program, Oklahoma Medical Research Foundation, University of Oklahoma, Oklahoma City, 73104, USA.
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21
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Michie AM, Trop S, Wiest DL, Zúñiga-Pflücker JC. Extracellular signal-regulated kinase (ERK) activation by the pre-T cell receptor in developing thymocytes in vivo. J Exp Med 1999; 190:1647-56. [PMID: 10587355 PMCID: PMC2195734 DOI: 10.1084/jem.190.11.1647] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/1999] [Accepted: 09/29/1999] [Indexed: 12/17/2022] Open
Abstract
The first checkpoint in T cell development occurs between the CD4(-)CD8(-) and CD4(+)CD8(+) stages and is associated with formation of the pre-T cell receptor (TCR). The signaling mechanisms that drive this progression remain largely unknown. Here, we show that extracellular signal-regulated kinases (ERKs)-1/2 are activated upon engagement of the pre-TCR. Using a novel experimental system, we demonstrate that expression of the pre-TCR by developing thymocytes induces ERK-1/2 activation within the thymus. In addition, the activation of this pre-TCR signaling cascade is mediated through Lck. These findings directly link pre-TCR complex formation with specific downstream signaling components in vivo.
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Affiliation(s)
- Alison M. Michie
- Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Sébastien Trop
- Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
- Department of Medicine, Division of Experimental Medicine, McGill University, Montréal, Québec H3A 1A3, Canada
| | - David L. Wiest
- Division of Basic Sciences, Immunobiology Working Group, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111
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22
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King LB, Tolosa E, Lenczowski JM, Lu F, Lind EF, Hunziker R, Petrie HT, Ashwell JD. A dominant-negative mutant of c-Jun inhibits cell cycle progression during the transition of CD4(-)CD8(-) to CD4(+)CD8(+) thymocytes. Int Immunol 1999; 11:1203-16. [PMID: 10421778 DOI: 10.1093/intimm/11.8.1203] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
While Jun/Fos-containing transcription factors are known to be necessary for many TCR-mediated events in mature T cells, relatively little is known about their roles in thymocyte development. We have generated transgenic mice that express a trans-dominant-negative mutant of c-Jun (TAM-67) specifically in thymocytes. Expression of TAM-67 inhibited the up-regulation of AP-1-responsive genes such as c-jun and IL-2 in stimulated thymocytes from transgenic mice. In addition, altered thymocyte development in TAM-67-expressing mice was revealed by a decrease in thymic cellularity ( approximately 50%) which could be accounted for primarily by a reduction in the number of CD4(+)CD8(+) thymocytes, a large percentage of which retained CD25. The decrease in the number of CD4(+)CD8(+) thymocytes did not appear to be due to an enhanced rate of apoptosis but rather to a decrease in the number of CD4(-)CD8(-)CD25(-) cells in the S + G(2)/M stages of the cell cycle. These results indicate that Jun/Fos-containing transcription factors promote the proliferative burst that accompanies the transition from the CD4(-)CD8(-) to the CD4(+)CD8(+) stage of thymocyte development.
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Affiliation(s)
- L B King
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda MD 20892, USA
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23
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Aifantis I, Feinberg J, Fehling HJ, Di Santo JP, von Boehmer H. Early T cell receptor beta gene expression is regulated by the pre-T cell receptor-CD3 complex. J Exp Med 1999; 190:141-4. [PMID: 10429678 PMCID: PMC2195557 DOI: 10.1084/jem.190.1.141] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We have examined the question of whether there is an additional checkpoint in T cell development that regulates T cell receptor (TCR)-beta expression in CD25+44- thymocytes by mechanisms that are independent of the pre-TCR. Our analysis in various mutant mice indicates that all changes in cytoplasmic TCR-beta expression can be accounted for by pre-TCR-dependent signal mediation, putting into question the function of a putative pro-TCR.
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Affiliation(s)
- I Aifantis
- Institut National de la Santé et de la Recherche Médicale (INSERM) U373, Hôpital Necker-Enfants Malades, Paris, France
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24
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Biro J, Würch A, Potocnik AJ, Falk I, Mossmann H, Eichmann K. Regulation of T cell receptor (TCR) beta gene expression by CD3 complex signaling in immature thymocytes: implications for TCRbeta allelic exclusion. Proc Natl Acad Sci U S A 1999; 96:3882-7. [PMID: 10097132 PMCID: PMC22389 DOI: 10.1073/pnas.96.7.3882] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
During alphabeta thymocyte development, clonotype-independent CD3 complexes are expressed at the cell surface before the pre-T cell receptor (TCR). Signaling through clonotype-independent CD3 complexes is required for expression of rearranged TCRbeta genes. On expression of a TCRbeta polypeptide chain, the pre-TCR is assembled, and TCRbeta locus allelic exclusion is established. We investigated the putative contribution of clonotype-independent CD3 complex signaling to TCRbeta locus allelic exclusion in mice single-deficient or double-deficient for CD3zeta/eta and/or p56(lck). These mice display defects in the expression of endogenous TCRbeta genes in immature thymocytes, proportional to the severity of CD3 complex malfunction. Exclusion of endogenous TCRbeta VDJ (variable, diversity, joining) rearrangements by a functional TCRbeta transgene was severely compromised in the single-deficient and double-deficient mutant mice. In contrast to wild-type mice, most of the CD25(+) double-negative (DN) thymocytes of the mutant mice failed to express the TCRbeta transgene, suggesting defective expression of the TCRbeta transgene similar to endogenous TCRbeta genes. In the mutant mice, a proportion of CD25(+) DN thymocytes that failed to express the transgene expressed endogenous TCRbeta polypeptide chains. Many double-positive cells of the mutant mice coexpressed endogenous and transgenic TCRbeta chains or more than one endogenous TCRbeta chain. The data suggest that signaling through clonotype-independent CD3 complexes may contribute to allelic exclusion of the TCRbeta locus by inducing the expression of rearranged TCRbeta genes in CD25(+) DN thymocytes.
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MESH Headings
- Alleles
- Animals
- Animals, Genetically Modified
- DNA Primers
- Gene Expression Regulation/immunology
- Gene Rearrangement, beta-Chain T-Cell Antigen Receptor
- Genes, T-Cell Receptor beta
- Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/deficiency
- Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/genetics
- Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/physiology
- Mice
- Mice, Knockout
- Receptor-CD3 Complex, Antigen, T-Cell/deficiency
- Receptor-CD3 Complex, Antigen, T-Cell/genetics
- Receptor-CD3 Complex, Antigen, T-Cell/physiology
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction
- T-Lymphocytes/immunology
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Affiliation(s)
- J Biro
- Max-Planck-Institut für Immunbiologie, D-79108 Freiburg, Germany
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25
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Würch A, Biro J, Falk I, Mossmann H, Eichmann K. Reduced Generation but Efficient TCRβ-Chain Selection of CD4+8+ Double-Positive Thymocytes in Mice with Compromised CD3 Complex Signaling. THE JOURNAL OF IMMUNOLOGY 1999. [DOI: 10.4049/jimmunol.162.5.2741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Maturation to the CD4+8+ double-positive (DP) stage of thymocyte development is restricted to cells that have passed TCRβ selection, an important checkpoint at which immature CD4−8− double-negative (DN) cells that express TCRβ polypeptide chains are selected for further maturation. The generation of DP thymocytes following TCRβ selection is dependent on cellular survival, differentiation, and proliferation, and the entire process appears to be mediated by the pre-TCR/CD3 complex. In this study, we investigate the signaling requirements for TCRβ selection using mice single deficient and double deficient for CD3ζ/η and/or p56lck. While the numbers of DP cells are strongly reduced in the single-deficient mice, a further drastic reduction in the generation of DP thymocytes is seen in the double-deficient mice. The poor generation of DP cells in the mutant mice is primarily due to an impaired ability of CD25+ DN thymocytes to proliferate following expression of a TCRβ-chain. Nevertheless, the residual DP cells in all mutant mice are strictly selected for expression of TCRβ polypeptide chains. DN thymocytes of mutant mice expressed TCRβ and CD3ε at the cell surface and contained mRNA for pre-Tα, but not for clonotypic TCRα-chains, together suggesting that TCRβ selection is mediated by pre-TCR signaling in all cases. The data suggest differential requirements of pre-TCR signaling for cell survival on the one hand, and for the proliferative burst associated with TCRβ selection on the other.
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Affiliation(s)
- Andreas Würch
- Max-Planck-Institut für Immunbiologie, Freiburg, Germany
| | - Judit Biro
- Max-Planck-Institut für Immunbiologie, Freiburg, Germany
| | - Ingrid Falk
- Max-Planck-Institut für Immunbiologie, Freiburg, Germany
| | - Horst Mossmann
- Max-Planck-Institut für Immunbiologie, Freiburg, Germany
| | - Klaus Eichmann
- Max-Planck-Institut für Immunbiologie, Freiburg, Germany
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26
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Bhandoola A, Cibotti R, Punt JA, Granger L, Adams AJ, Sharrow SO, Singer A. Positive selection as a developmental progression initiated by alpha beta TCR signals that fix TCR specificity prior to lineage commitment. Immunity 1999; 10:301-11. [PMID: 10204486 DOI: 10.1016/s1074-7613(00)80030-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
During positive selection, immature thymocytes commit to either the CD4+ or CD8+ T cell lineage ("commitment") and convert from short-lived thymocytes into long-lived T cells ("rescue"). By formal precursor-progeny analysis, we now identify what is likely to be the initial positive selection step signaled by alpha beta TCR, which we have termed "induction". During induction, RAG mRNA expression is downregulated, but lineage commitment does not occur. Rather, lineage commitment (which depends upon the MHC class specificity of the alpha beta TCR) only occurs after downregulation of RAG expression and the consequent fixation of alpha beta TCR specificity. We propose that positive selection can be viewed as a sequence of increasingly selective developmental steps (induction-->commitment-->rescue) that are signaled by alpha beta TCR engagements of intrathymic ligands.
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MESH Headings
- Animals
- CD3 Complex/physiology
- CD5 Antigens/physiology
- Cell Differentiation/immunology
- Cell Lineage/immunology
- Clonal Deletion/immunology
- DNA-Binding Proteins/antagonists & inhibitors
- DNA-Binding Proteins/biosynthesis
- Down-Regulation/immunology
- Epitopes, T-Lymphocyte/metabolism
- Hematopoietic Stem Cells/immunology
- Hematopoietic Stem Cells/metabolism
- Histocompatibility Antigens Class I/immunology
- Homeodomain Proteins/antagonists & inhibitors
- Homeodomain Proteins/biosynthesis
- Mice
- Mice, Congenic
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Receptors, Antigen, T-Cell, alpha-beta/analysis
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Signal Transduction/immunology
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocytes/chemistry
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
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Affiliation(s)
- A Bhandoola
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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27
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Wilson A, MacDonald HR. A Limited Role for β-Selection During γδ T Cell Development. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.161.11.5851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
T cells belong to two distinct lineages expressing either αβ or γδ TCR. During αβ T cell development, it is clearly established that productive rearrangement at the TCR β locus in immature precursor cells leads to the expression of a pre-TCR complex. Signaling through the pre-TCR results in the selective proliferation and maturation of TCR β+ cells, a process that is known as β-selection. However, the potential role of β-selection during γδ T cell development is controversial. Whereas PCR-RFLP and sequencing techniques have provided evidence for a bias toward in-frame VDJβ rearrangements in γδ cells (consistent with β-selection), γδ cells apparently develop normally in mice that are unable to assemble a pre-TCR complex due to a deficiency in TCR β or pTα genes. In this report, we have directly addressed the physiologic significance of β-selection during γδ cell development in normal mice by quantitating intracellular TCR β protein in γδ cells and correlating its presence with cell cycle status. Our results indicate that β-selection plays a significant (although limited) role in γδ cell development by selectively amplifying a minor subset of γδ precursor cells with productively rearranged TCR β genes.
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Affiliation(s)
- Anne Wilson
- Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Epalinges, Switzerland
| | - H. Robson MacDonald
- Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Epalinges, Switzerland
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28
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Würch A, Biro J, Potocnik AJ, Falk I, Mossmann H, Eichmann K. Requirement of CD3 complex-associated signaling functions for expression of rearranged T cell receptor beta VDJ genes in early thymic development. J Exp Med 1998; 188:1669-78. [PMID: 9802979 PMCID: PMC2212509 DOI: 10.1084/jem.188.9.1669] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
During alpha beta thymocyte development, the clonotypic alpha beta-T cell receptor (TCR) is preceded by sequentially expressed immature versions of the TCR-CD3 complex: the pre-TCR, containing a clonotypic TCR-beta chain and invariant pre-Talpha, is expressed on pre-T cells before rearrangement of the TCR-alpha locus. Moreover, clonotype-independent CD3 complexes (CIC) appear on pro-T cells before VDJ rearrangements of TCR-beta genes. The pre-TCR is known to mediate TCR-beta selection, the prerequisite for maturation of CD4(-)8(-) double negative (DN) thymocytes to the CD4(+)8(+) double positive stage. A developmental function of CIC has so far not been delineated. In mice single deficient and double deficient for CD3zeta/eta and/or p56(lck), we observe a pronounced reduction in the proportions of CD25(+) DN thymocytes that express intracellular TCR-beta chains. TCR-beta transcripts are reduced in parallel with TCR-beta polypeptide chains whereas no reduction in TCR-beta locus rearrangements could be detected. Wild-type levels of TCR-beta transcripts and of cells expressing TCR-beta polypeptide chains are induced by treatment with anti-CD3epsilon mAb. The data suggest that the initial expression of rearranged TCR-beta VDJ genes in pro-T cell to pre-T cell progression is dependent on CD3 complex signaling, and thus define a putative developmental function for CIC.
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Affiliation(s)
- A Würch
- Max-Planck-Institut für Immunbiologie, D-79108 Freiburg, Germany
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29
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Basson MA, Bommhardt U, Mee PJ, Tybulewicz VL, Zamoyska R. Molecular requirements for lineage commitment in the thymus--antibody-mediated receptor engagements reveal a central role for lck in lineage decisions. Immunol Rev 1998; 165:181-94. [PMID: 9850861 DOI: 10.1111/j.1600-065x.1998.tb01239.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recent experiments in our laboratory have focused on the receptor engagements required for the differentiation of fully mature, single positive thymocytes from their double positive precursors. We have used a novel approach which involves the ligation of surface receptors on immature thymocytes with genetically engineered F(ab1)2 reagents, which, unlike conventional antibodies, do not aggregate the CD3 complex to such an extent as to induce extensive deletion of these cells. The experimental data presented in this review indicate that differentiation of the two mature CD4 and CD8 lineages occurs in response to distinct intracellular signals induced by particular receptor engagements. The data suggest that the tyrosine kinase p56lck (lck) plays a crucial role in determining lineage choice, in that maturation of thymocytes into the CD4 lineage occurs upon recruitment of active lck to the T-cell receptor (TCR)/CD3 complex, whereas CD8 maturation can be induced by CD3 ligation in the absence of co-receptor-mediated lck recruitment. A central role for lck activity in determining the threshold for differentiation of the CD4 lineage is revealed in experiments with thymi deficient for a regulator of lck activity, CD45. A model of thymocyte differentiation is presented in which we propose that the relative balance of signals delivered by TCR engagement and lck activation determines lineage choice.
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Affiliation(s)
- M A Basson
- Division of Molecular Immunology, National Institute for Medical Research, London, UK
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30
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Abstract
Interleukin-7 (IL-7) is a non redundant cytokine in thymic T-cell development. It binds to a dimeric receptor consisting of a specific IL-7Ralpha and a gamma-common subunit that it shares with the receptors for IL-2, 4, 9, 13 and 15. IL-7 is critical for early T-cell development but it also acts on immature B-cells and mature T-cells, and leads to secondary cytokine release. Its mechanisms of action in early T-cell development may be multiple. There is direct evidence to support a mechanistic involvement in TCR-gamma rearrangement that drives further TCR-gammadelta thymocyte commitment and maturation. There is indirect evidence for a role of IL-7 in TCR-beta rearrangement. It may however also act as a survival factor for TCR-beta rearranging thymocytes while the critical commitment selections are effected by other factors. The effects of IL-7 in fetal thymus organ culture are dose dependent, with a biphasic response: low doses of IL-7 are necessary for normal TCR-alphabeta thymocyte development but high doses block TCR-alphabeta maturation in favor of TCR-gammadelta development. A good understanding of the dose response of IL-7 in thymocyte development, mature T-cell stimulation, and of the release of secondary cytokines will be important for planning successful clinical trials with IL-7.
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Affiliation(s)
- F Offner
- Department of Clinical Chemistry, University Hospital Ghent, Belgium
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31
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Schneider MK, Grönvik KO. CD4-CD8-C.B-17 SCID thymocytes enter the CD4+CD8+ stage in the presence of neonatally grafted T cells. Scand J Immunol 1998; 47:466-74. [PMID: 9627131 DOI: 10.1046/j.1365-3083.1998.00331.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this work was to study the selection of donor T cells and their influence on thymic development in C.B-17 scid/scid (severe combined immunodeficient; SCID) mice during chronic graft-versus-host disease (GVHD). Recipient SCID mice (H-2d), neonatally grafted with allogeneic peripheral T cells from CBA/J strain (H-2k) of mice, only developed a mild acute GVHD, and were, at the chronic stage, devoid of pathological symptoms. Thymic cell numbers of injected mice differed from 10(5) to 1.2 x 10(7) at 2-3 weeks post-injection (p.i.), and from 4 x 10(5) to 8.5 x 10(7) at 2 months p.i. In these mice, the thymus size was correlated to the CD4-CD8- (double negative; DN) to CD4+CD8+ (double positive; DP) cell ratio, where at 2 months p.i., 8 out of 16 treated SCID mice contained 5 x 10(6) cells or more and also possessed the highest frequencies of endogenous DP cells (25-95%). In contrast to previous findings, peripheral donor T cells from allogeneic and syngeneic mice, infiltrating the host thymus, had a positive effect on the development of endogenous DP thymocytes. Furthermore, these thymocytes were developmentally blocked at the DP stage, occasionally in combination with the expression of CD25, CD44 and CD117 but in the absence of T-cell receptor (TCR) expression. Also, at this time-point, the CBA/J donor TCR Vbeta repertoire was equal to that of normal CBA/J mice, but purified responding donor cells were proliferatively inhibited against H-2d stimulators in ex vivo mixed lymphocyte cultures. In contrast, the same responders showed a pronounced proliferation against syngeneic H-2Kk stimulators, suggesting either a reversion from anergy of autoreactive CBA/J T cells or a vast expansion of multiple self-reactive T-cell clones, when parked in a milieu with a lower concentration of self-antigens.
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MESH Headings
- Age Factors
- Animals
- Animals, Newborn
- CD2 Antigens/analysis
- CD3 Complex/analysis
- CD4 Antigens/analysis
- CD4-Positive T-Lymphocytes/cytology
- CD4-Positive T-Lymphocytes/immunology
- CD8 Antigens/analysis
- CD8-Positive T-Lymphocytes/cytology
- CD8-Positive T-Lymphocytes/immunology
- Cell Count
- Cell Differentiation
- Chronic Disease
- Graft vs Host Disease/pathology
- Lymphocyte Activation/immunology
- Major Histocompatibility Complex/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, SCID
- Proto-Oncogene Proteins c-kit/analysis
- Receptors, Antigen, T-Cell, alpha-beta/analysis
- Receptors, Interleukin-2/analysis
- Severe Combined Immunodeficiency/immunology
- Severe Combined Immunodeficiency/pathology
- T-Lymphocytes/immunology
- T-Lymphocytes/transplantation
- Thymus Gland/cytology
- Thymus Gland/growth & development
- Time Factors
- Transplantation, Homologous
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Affiliation(s)
- M K Schneider
- Department of Vaccine Research, National Veterinary Institute, Uppsala University, Sweden
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32
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Basson MA, Bommhardt U, Cole MS, Tso JY, Zamoyska R. CD3 ligation on immature thymocytes generates antagonist-like signals appropriate for CD8 lineage commitment, independently of T cell receptor specificity. J Exp Med 1998; 187:1249-60. [PMID: 9547336 PMCID: PMC2212221 DOI: 10.1084/jem.187.8.1249] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The signals that direct differentiation of T cells to the CD4 or CD8 lineages in the thymus remain poorly understood. Although it has been relatively easy to direct differentiation of CD4 single positive (CD4+) cells using combinations of antibodies and pharmacological agents that mimic receptor engagements, equivalent stimuli do not induce efficient maturation of CD8+ cells. Here we report that, irrespective of the MHC-restriction specificity of the TCR, differentiation of mature CD8+ thymocytes can be induced by ligation of CD3 polypeptides on immature thymocytes with a F(ab')2 reagent (CD3fos-F(ab')2). The tyrosine phosphorylation patterns stimulated by CD3fos-F(ab')2 have been shown to resemble those delivered to mature T cells by antagonist peptides, which are known to direct positive selection of CD8+ cells, and we can show that this reagent exhibits potent antagonistic-like activity for primary T cell responses. Our results suggest a distinction in the signals that specify lineage commitment in the thymus. We present a model of thymocyte differentiation that proposes that the relative balance of signals delivered by TCR engagement and by p56lck activation is responsible for directing commitment to the CD8 or CD4 lineages.
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Affiliation(s)
- M A Basson
- Division of Molecular Immunology, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, United Kingdom
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33
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Fehling HJ, Gilfillan S, Ceredig R. αβ/γδ Lineage Commitment in the Thymus of Normal and Genetically Manipulated Mice. Adv Immunol 1998. [DOI: 10.1016/s0065-2776(08)60399-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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34
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Nagata K, Nakamura T, Kitamura F, Kuramochi S, Taki S, Campbell KS, Karasuyama H. The Ig alpha/Igbeta heterodimer on mu-negative proB cells is competent for transducing signals to induce early B cell differentiation. Immunity 1997; 7:559-70. [PMID: 9354476 DOI: 10.1016/s1074-7613(00)80377-5] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The immunoglobulin alpha (Ig alpha)/Ig beta heterodimer was detected on the surface of mu-negative proB cell lines in association with calnexin. The cross-linking of Ig beta on proB cells freshly isolated from bone marrow of recombination activating gene (RAG)-2-deficient mice induced a rapid and transient tyrosine-phosphorylation of Ig alpha as well as an array of intracellular proteins including Syk, PI3-kinase, Vav, and SLP-76. It also elicited the phosphorylation and activation of a MAP kinase ERK but not JNK/SAPK or p38. When RAG-2-deficient mice were treated with anti-Ig beta monoclonal antibody, developmentally arrested proB cells were induced to differentiate to the small preB cell stage as observed when the mu transgene was expressed in RAG-2-deficient mice. Thus, the cross-linking of Ig beta on proB cells appears to elicit differentiation signals analogous to those delivered by the preB cell receptor in normal B cell development.
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Affiliation(s)
- K Nagata
- Department of Immunology, The Tokyo Metropolitan Institute of Medical Science, Japan
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35
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Abstract
The pre-T cell receptor (pre-TCR) that minimally consists of the TCR beta chain and the disulfide-linked pre-T cell receptor alpha (pT alpha) chain in association with signal-transducing CD3 molecules rescues from programmed cell death cells with productive TCR beta rearrangements. The pre-TCR induces expansion and differentiation of these cells such that they become TCR alpha beta bearing CD4+8+ thymocytes, which express only a single TCR beta chain and then either die of neglect or--upon TCR-ligand interaction--undergo either positive or negative selection. The newly discovered pT alpha gene encodes a transmembrane protein that belongs to the Ig superfamily and contains a cytoplasmic tail that, however, has no essential function in signal transduction, which is mediated by CD3 molecules and most likely p56lck. Experiments in pT alpha gene-deficient mice show that the pre-TCR has a crucial role in maturation as well as allelic exclusion of alpha beta T cells but is not required for the development of gamma delta-expressing cells. The function of the pre-TCR cannot be fully assumed by an alpha beta TCR that is expressed abnormally early in T cell development.
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MESH Headings
- Animals
- CD3 Complex/metabolism
- Cell Differentiation
- Chromosome Mapping
- Gene Expression Regulation, Developmental
- Humans
- Membrane Glycoproteins/chemistry
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/metabolism
- Mice
- Molecular Structure
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Signal Transduction
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocytes/cytology
- T-Lymphocytes/immunology
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36
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Falk I, Biro J, Kohler H, Eichmann K. Proliferation kinetics associated with T cell receptor-beta chain selection of fetal murine thymocytes. J Exp Med 1996; 184:2327-39. [PMID: 8976187 PMCID: PMC2196377 DOI: 10.1084/jem.184.6.2327] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
After productive rearrangement of a TCR beta chain gene, CD4-8- double negative (DN) thymocytes express TCR beta polypeptide chains on the cell surface together with pre-T alpha and the CD3 complex forming the pre-TCR. Signals transmitted through the pre-TCR select TCR beta + DN thymocytes for further maturation to the CD4+8+ double positive stage, whereas DN cells that fail to generate a productive TCR beta gene rearrangement do not continue in development. This process is termed TCR beta chain selection. Although it is likely that differences between proliferation dynamics of TCR beta + and TCR beta-cells may play a role, the exact mechanisms of TCR beta chain selection have not been elucidated. We therefore studied the proliferation dynamics of TCR beta + and TCR beta-thymocytes during fetal development, i.e., when TCR beta chain selection takes place for the first time. We analyzed in situ accumulation of TCR beta + thymocytes by confocal microscopy, and determined cell cycle and division parameters of TCR beta + and TCR beta-populations by flow cytometry. About 600 TCR beta + cells/thymic lobe are generated by independent induction events between days of gestation (dg) 13.5, and 15.5. As of dg 14.5, most TCR beta + cells have entered S/G2 phase of cell cycle, followed by seven to eight rapid cell divisions in fetal thymic organ culture, suggesting a corresponding burst of nine cell divisions within 4 d in vivo. By dg 18.5, the division rate of TCR beta + cells has slowed down to less than 1/d. About three quarters of TCR beta-cells divide at a slow rate of 1/d on dg 14.5, the proportion of nondividing cells increasing to 50% within the following four d. From dg 16.5 onwards, TCR beta-cells, but not TCR beta + cells, contain a significant proportion of apoptotic cells. The results suggest that failure to become selected results in shutdown of proliferation and eventual programmed cell death of fetal TCR beta-cells. Positive selection of fetal TCR beta + cells is achieved by an increased rate of cell divisions lasting for approximately 4 d.
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Affiliation(s)
- I Falk
- Max-Planck-Institut für Immunbiologie, Freiburg, Germany
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37
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Nacht M, Strasser A, Chan YR, Harris AW, Schlissel M, Bronson RT, Jacks T. Mutations in the p53 and SCID genes cooperate in tumorigenesis. Genes Dev 1996; 10:2055-66. [PMID: 8769648 DOI: 10.1101/gad.10.16.2055] [Citation(s) in RCA: 136] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
DNA damage can cause mutations that contribute to cellular transformation and tumorigenesis. The p53 tumor suppressor acts to protect the organism from DNA damage by inducing either G1 arrest to facilitate DNA repair or by activating physiological cell death (apoptosis). Consistent with this critical function of p53, mice lacking p53 are predisposed to developing tumors, particularly lymphoma. The severe combined immune deficiency (scid) focus encodes the catalytic subunit of DNA protein kinase (DNA-PKcs), a protein complex that has a role in the cellular response to DNA damage. Cells from scid mice are hypersensitive to radiation and scid lymphocytes fail to develop from precursors because they are unable to properly join DNA-coding ends during antigen receptor gene rearrangement. We examined the combined effect of loss of p53 and loss of DNA-PKcs on lymphocyte development and tumorigenesis by generating p53-/- scid mice. Our data demonstrate that loss of p53 promotes T-cell development in scid mice but does not noticeably affect B lymphopoiesis. Moreover, scid cells are able to induce p53 protein expression and activate G1 arrest or apoptosis in response to ionizing radiation, indicating that DNA-PKcs is not essential for these responses to DNA damage. Furthermore, p53-/- scid double mutant mice develop lymphoma earlier than p53-/- littermates, demonstrating that loss of these two genes can cooperate in tumorigenesis. Collectively, these results provide evidence for an unsuspected role of p53 as a checkpoint regulator in early T-cell development and demonstrate that loss of an additional component of the cellular response to DNA damage can cooperate with loss of p53 in lymphomagenesis.
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MESH Headings
- Animals
- Apoptosis
- Bone Marrow Cells
- Cell Cycle/radiation effects
- Cells, Cultured
- DNA Damage
- DNA-Activated Protein Kinase
- DNA-Binding Proteins
- Gene Expression Regulation, Developmental
- Gene Rearrangement, B-Lymphocyte
- Gene Rearrangement, T-Lymphocyte
- Genes, p53
- Lymphocyte Subsets/cytology
- Lymphoma/genetics
- Mice
- Mice, Mutant Strains
- Mice, SCID/genetics
- Protein Serine-Threonine Kinases/physiology
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Thymus Gland/cytology
- Tumor Suppressor Protein p53/physiology
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Affiliation(s)
- M Nacht
- Howard Hughes Medical Institute, Center for Cancer Research, Massachusetts Institute of Technology, Cambridge 02139, USA
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38
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Heiken H, Schulz RJ, Ravetch JV, Reinherz EL, Koyasu S. T lymphocyte development in the absence of Fc epsilon receptor I gamma subunit: analysis of thymic-dependent and independent alpha beta and gamma delta pathways. Eur J Immunol 1996; 26:1935-43. [PMID: 8765042 DOI: 10.1002/eji.1830260839] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
During fetal development, early thymocyte progenitors transiently express low affinity Fc receptors for IgG (Fc gamma R) of both Fc gamma RII and III isoforms. Only the Fc gamma RIII isoform requires association of an Fc gamma RIII (CD16) alpha subunit with an Fc epsilon RI gamma homodimer for surface expression. To address the role of Fc gamma R in ontogeny, we studied thymic development in Fc epsilon RI gamma-/- mice. We fine that day 14.5 CD4-CD8- double-negative (DN) fetal thymocytes of Fc epsilon RI gamma-/- mice express mRNA of both Fc gamma RIIb1 and Fc gamma RIII. Surface expression of Fc gamma RII/III is readily detected on these cells. It appears that Fc gamma RIIb1, whose surface expression is Fc epsilon RI gamma independent, replaces Fc gamma RIII during thymic development in these animals. Moreover, subsequent development into CD4+CD8+ double-positive and CD4+CD8- and CD4-CD8+ single-positive subsets appears normal even in the absence of Fc epsilon RI gamma. However, alterations were noted in adult animals among the DN alpha beta TCR+ thymocytes and peripheral splenic DN T cells as well as CD8 alpha alpha + intestinal intraepithelial lymphocytes (iIEL). In contrast to conventional T lymphocytes, which do not express either Fc gamma RIII or Fc epsilon RI gamma, DN alpha beta TCR+ thymocytes and extrathymically derived alpha beta TCR+ and gamma delta TCR+ CD8 alpha alpha + beta- iIEL express TCR which incorporate Fc epsilon RI gamma as one of their subunits. Consistent with this, the TCR levels of these cells are lower than the TCR levels on cells from wild-type C57BL/6 mice. Despite the reduction in the level of surface TCR, the development of these cells was unaltered by the absence of Fc epsilon RI gamma. Thus, we observed alterations in adult DN alpha beta TCR+ thymocytes, splenic DN alpha beta TCR+ and DN gamma delta TCR+ large granular lymphocytes (LGL), and alpha beta TCR+ and gamma delta TCR+ CD8 alpha alpha+beta- iIEL, but no detectable changes in their major fetal thymic developmental pathways. Cultivation of peripheral DN alpha beta TCR+ and DN gamma delta TCR+ cells from Fc epsilon RI gamma-/- mice with interleukin-2 generates LGL which mediate natural killer activity. Unlike LGL from wild-type C57BL/6 mice, LGL from Fc epsilon RI gamma-/- mice lack Fc gamma RIII expression and could not mediate antibody-dependent cellular cytotoxicity through Fc gamma RIII.
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MESH Headings
- Aging
- Animals
- Antibodies, Monoclonal/pharmacology
- Antigens, T-Independent/immunology
- Base Sequence
- Cell Differentiation/immunology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Molecular Sequence Data
- Organ Culture Techniques
- Polymerase Chain Reaction
- Receptors, Antigen, T-Cell, alpha-beta/analysis
- Receptors, Antigen, T-Cell, alpha-beta/physiology
- Receptors, Antigen, T-Cell, gamma-delta/analysis
- Receptors, Antigen, T-Cell, gamma-delta/physiology
- Receptors, IgE/deficiency
- Receptors, IgE/immunology
- Receptors, IgG/deficiency
- Receptors, IgG/immunology
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
- Thymus Gland/cytology
- Thymus Gland/immunology
- Thymus Gland/metabolism
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Affiliation(s)
- H Heiken
- Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
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39
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Abstract
Interactions between stromal cells and thymocytes play a crucial role in T cell development. The thymic stroma is complex and consists of epithelial cells derived from the pharyngeal region during development, together with macrophages and dendritic cells of bone marrow origin. In addition, fibroblasts and matrix molecules permeate the whole framework. It is now apparent that these individual stromal components play specialized roles at different stages of T cell differentiation. Thus, at the early CD4-8- stage of development, T cell precursors require fibroblast as well as epithelial cell interactions. Later, at the CD4+8+ stage, as well as providing low avidity TCR/MHC-peptide interactions, thymic epithelial cells have been shown to possess unique properties essential for positive selection. Dendritic cells, on the other hand, are probably efficient mediators of negative selection, but they may not be solely responsible for this activity. Alongside the functional roles of stromal cells, considerable progress is being made in unraveling the nature of the signaling pathways involved in T cell development. Identification of the pre-T cell receptor (pre-TCR) and associated signaling molecules marks an important advance in understanding the mechanisms that control gene rearrangement and allelic exclusion. In addition, a better understanding of the signaling pathways that lead to positive selection on the one hand and negative selection on the other is beginning to emerge. Many issues remain unresolved, and some are discussed in this review. What, for example, is the nature of the chemotactic factor(s) that attract stem cells to the thymus? What is the molecular basis of the essential interactions between early thymocytes and fibroblasts, and early thymocytes and epithelial cells? What is special about cortical epithelial cells in supporting positive selection? These and other issues are ripe for analysis and can now be approached using a combination of modern molecular and cellular techniques.
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Affiliation(s)
- G Anderson
- Department of Anatomy, Medical School, University of Birmingham, United Kingdom
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40
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Abstract
T lymphocytes differentiate from hematopoietic stem cells that settle in the microenvironment of the thymus. The earliest stages of mouse alpha/beta T-cell differentiation occurring before surface expression of the TCR include three important events: proliferation, commitment to the T lineage, and rearrangement and expression of the TCR loci. Recent evidence suggests that the survival as well as differentiation of early thymocytes depends critically on molecular signals such as those generated by the recently described pre-TCR complex.
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41
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Bogue MA, Zhu C, Aguilar-Cordova E, Donehower LA, Roth DB. p53 is required for both radiation-induced differentiation and rescue of V(D)J rearrangement in scid mouse thymocytes. Genes Dev 1996; 10:553-65. [PMID: 8598286 DOI: 10.1101/gad.10.5.553] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The murine scid mutation affects both V(D)J recombination and DNA repair. This mutation has been mapped to the gene encoding the catalytic subunit of the DNA-dependent protein kinase (DNA-PK), which is activated by DNA damage in normal cells. In scid mice, antigen receptor gene rearrangements are initiated normally, but impaired joining of coding ends prevents assembly of functional receptor genes, resulting in arrest of B- and T-cell development. Others have shown that exposure of scid mice to genotoxic agents such as gamma-irradiation rescues rearrangement at the T-cell receptor (TCR) beta locus and promotes thymocyte development. Here we demonstrate that irradiation rescues rearrangements at multiple TCR loci, suggesting a general effect on the recombination mechanism. Furthermore, our data show that p53 is required for irradiation-mediated rescue of both thymocyte development and V(D)J recombination. We also find that thymocyte proliferation and differentiation in the absence of DNA damage do not require p53 and are not sufficient to rescue V(D)J recombination. These results suggest that exposure to ionizing radiation facilitates a partial bypass of the scid defect, perhaps by inducing p53-dependent DNA damage response pathways.
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Affiliation(s)
- M A Bogue
- Department of Microbiology and Immunology, Baylor College of Medicine, Houston, Texas 77030, USA
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42
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Abstract
Early stages of T cell development are thought to include a series of coordinated interactions between thymocytes and other cells of the thymus. A monoclonal antibody specific for mouse CD81 was identified that blocked the appearance of alpha beta but not gamma delta T cells in fetal organ cultures initiated with day 14.5 thymus lobes. In reaggregation cultures with CD81-transfected fibroblasts, CD4-CD8- thymocytes differentiated into CD4+CD8+ T cells. Thus, interactions between immature thymocytes and stromal cells expressing CD81 are required and may be sufficient to induce early events associated with T cell development.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/immunology
- Antigens, CD/genetics
- Antigens, CD/immunology
- Antigens, CD/physiology
- Base Sequence
- CD4 Antigens/analysis
- CD8 Antigens/analysis
- CHO Cells
- Cell Differentiation
- Cricetinae
- Membrane Proteins/immunology
- Membrane Proteins/physiology
- Mice
- Molecular Sequence Data
- Organ Culture Techniques
- Receptors, Antigen, T-Cell, alpha-beta/analysis
- Receptors, Antigen, T-Cell, gamma-delta/analysis
- Stromal Cells/immunology
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- Tetraspanin 28
- Thymus Gland/cytology
- Thymus Gland/immunology
- Transfection
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Affiliation(s)
- R Boismenu
- Department of Immunology, Scripps Research Institute, La Jolla, CA 92037, USA
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43
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Bhatia SK, Rose NR. Chapter 13 Autoimmunity and autoimmune disease. Immunobiology 1996. [DOI: 10.1016/s1569-2582(96)80081-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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44
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Shores EW, Love PE. Insights into T cell development and signal transduction provided by TCR-zeta chain deficient mice. Int Rev Immunol 1996; 13:301-15. [PMID: 8884427 DOI: 10.3109/08830189609061754] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The T cell antigen receptor (TCR) transduces signals that mediate different responses depending on the stage of development of the T cell and the nature of the ligand it engages. The presence of multiple signal transducing subunits (CD3-gamma-delta,-epsilon and zeta chain) suggests the potential to control these responses by altering the subunit composition of the TCR. zeta chain represents an especially important signalling molecule as it contains multiple signalling motifs within its cytoplasmic tail. The generation and analysis of zeta deficient (zeta-/-) and zeta-transgenic mice has provided insight into the role of zeta as well as the CD3 subunits in TCR surface expression, T cell activation and thymocyte development. Herein, we discuss the results from such experiments which suggest distinct roles for zeta chain and the CD3 components at different stages of T cell development.
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Affiliation(s)
- E W Shores
- Division of Hematologic Products, Food and Drug Administration, Bethesda, MD 20892, USA
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Affiliation(s)
- C N Levelt
- Max-Planck-Institut für Immunbiologie, Freiburg, Federal Republic of Germany
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Mazda O, Aiba Y, Hattori N, Li M, Fujimoto S, Davis MM, Katsura Y. Abrogation of the allelic exclusion in a T cell receptor beta chain gene transgenic mouse strain. Immunol Invest 1995; 24:927-46. [PMID: 8575838 DOI: 10.3109/08820139509060718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The expression of endogenous T cell receptor (TcR) beta chains in a TcR beta chain gene transgenic mouse (TGM) strain was examined. Unlike many other TGM strains reported, a considerable proportion of T cells from the thymus and spleen as well as organ cultured fetal thymus from our TGM express endogenous TCR beta chains on their surface. Compatible with this was the elucidation of VDJ rearrangement of endogenous beta chain genes by PCR. Three color flow cytometric analysis of thymus cell subpopulations revealed that the expression levels of both endogenous and transgenic TcR beta genes are regulated in a maturational stage specific manner. Splenic T cells contained a several fold higher percentage of endogenous TcR beta positive cells than thymus cells, suggesting a role of TcR on T cell peripherization. V beta 6 positive cells were deleted in the TGM carrying minor lymphocyte stimulating (Mls)-la antigen, indicating that the endogenous TcR beta is functional in terms of transmitting a signal for clonal deletion.
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MESH Headings
- Alleles
- Animals
- Cell Line
- Cytochrome c Group/genetics
- Cytochrome c Group/immunology
- Enhancer Elements, Genetic/immunology
- Female
- Gene Rearrangement, beta-Chain T-Cell Antigen Receptor/immunology
- Immunoglobulin Heavy Chains/genetics
- Male
- Mice
- Mice, Inbred AKR
- Mice, Inbred C57BL
- Mice, Transgenic/immunology
- Organ Culture Techniques
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- T-Lymphocytes/immunology
- Thymus Gland
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Affiliation(s)
- O Mazda
- Department of Immunology, Chest Disease Research Institute, Kyoto University, Japan
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King LB, Vacchio MS, Dixon K, Hunziker R, Margulies DH, Ashwell JD. A targeted glucocorticoid receptor antisense transgene increases thymocyte apoptosis and alters thymocyte development. Immunity 1995; 3:647-56. [PMID: 7584154 DOI: 10.1016/1074-7613(95)90135-3] [Citation(s) in RCA: 135] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The exquisite sensitivity of thymocytes to steroid-induced apoptosis, the steroidogenic potential of thymic epithelial cells, and the ability of steroid synthesis inhibitors to enhance antigen-specific deletion of thymocytes in fetal thymic organ cultures suggest a role for glucocorticoids in thymocyte development. To address this further, transgenic mice that express antisense transcripts to the glucocorticoid receptor (GR) specifically in immature thymocytes were generated. The consequent hyporesponsiveness of thymocytes to glucocorticoids was accompanied by a reduction in thymic size, primarily owing to a decrease in the number of CD4+CD8+ cells. While an enhanced susceptibility to T cell receptor (TCR)-mediated apoptosis appeared to be partially responsible for this reduction, thymocyte loss could also be detected before thymocytes progressed to the CD4+CD8+ TCR alpha beta-expressing stage. These results suggest that glucocorticoids are necessary for survival and maturation of thymocytes, and are consistent with a role for steroids in both the transition from CD4-CD8- to CD4+CD8+ cells and the survival of CD4+CD8+ cells stimulated via the TCR.
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Affiliation(s)
- L B King
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health Bethesda, Maryland 20892, USA
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48
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MESH Headings
- Animals
- Antigens, Differentiation, T-Lymphocyte/immunology
- Humans
- Major Histocompatibility Complex
- Mice
- Mice, Transgenic
- Models, Immunological
- Models, Structural
- Protein Precursors/chemistry
- Protein Precursors/immunology
- Receptors, Antigen, T-Cell/biosynthesis
- Receptors, Antigen, T-Cell/chemistry
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- T-Lymphocytes/immunology
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von Boehmer H. T cell differentiation: control by the pre-TCR and alpha beta TCR. CLINICAL IMMUNOLOGY AND IMMUNOPATHOLOGY 1995; 76:S145-50. [PMID: 7554457 DOI: 10.1016/s0090-1229(95)90018-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
MESH Headings
- Animals
- Cell Differentiation
- Gene Rearrangement, T-Lymphocyte/genetics
- Lymphocyte Activation/immunology
- Mice
- Mice, Mutant Strains
- Protein Precursors/pharmacology
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/physiology
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/physiology
- Selection, Genetic
- T-Lymphocytes/cytology
- T-Lymphocytes/immunology
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50
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Levelt CN, Mombaerts P, Wang B, Kohler H, Tonegawa S, Eichmann K, Terhorst C. Regulation of thymocyte development through CD3: functional dissociation between p56lck and CD3 sigma in early thymic selection. Immunity 1995; 3:215-22. [PMID: 7648394 DOI: 10.1016/1074-7613(95)90091-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We studied the extent of functional linkage between CD3 sigma and p56lck in pre-TCR-dependent thymocyte development. Differentiation of DN to DP cells was examined by treatment of RAG2/CD3 sigma and RAG1/p56lck double-deficient mice with anti-CD3 epsilon antibodies. The results suggest that CD3 sigma has no specific role in this maturation step, but may be important for amplification of signaling through the pre-TCR. In contrast, p56lck is the main protein tyrosine kinase associated with signaling through the pre-TCR-CD3 complex. In DP thymocytes, the Ca2+ response to anti-CD3 epsilon was totally abolished in CD3 sigma-I-but only reduced in p56lck-I-mice, and in vivo responses to anti-CD3 epsilon differed from one another. Thus, CD3 sigma and p56lck are functionally not tightly associated and their deficiencies cause distinct developmental defects.
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Affiliation(s)
- C N Levelt
- Max Planck Institut für Immunobiologie, Freiburg, Federal Republic of Germany
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