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Wu G, Xu Y, Schultz RD, Chen H, Xie J, Deng M, Liu X, Gui X, John S, Lu Z, Arase H, Zhang N, An Z, Zhang CC. LILRB3 supports acute myeloid leukemia development and regulates T-cell antitumor immune responses through the TRAF2-cFLIP-NF-κB signaling axis. NATURE CANCER 2021; 2:1170-1184. [PMID: 35122056 PMCID: PMC8809885 DOI: 10.1038/s43018-021-00262-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 08/24/2021] [Indexed: 01/08/2023]
Abstract
Leukocyte immunoglobulin-like receptor B (LILRB), a family of immune checkpoint receptors, contributes to acute myeloid leukemia (AML) development, but the specific mechanisms triggered by activation or inhibition of these immune checkpoints in cancer is largely unknown. Here we demonstrate that the intracellular domain of LILRB3 is constitutively associated with the adaptor protein TRAF2. Activated LILRB3 in AML cells leads to recruitment of cFLIP and subsequent NF-κB upregulation, resulting in enhanced leukemic cell survival and inhibition of T-cell-mediated anti-tumor activity. Hyperactivation of NF-κB induces a negative regulatory feedback loop mediated by A20, which disrupts the interaction of LILRB3 and TRAF2; consequently the SHP-1/2-mediated inhibitory activity of LILRB3 becomes dominant. Finally, we show that blockade of LILRB3 signaling with antagonizing antibodies hampers AML progression. LILRB3 thus exerts context-dependent activating and inhibitory functions, and targeting LILRB3 may become a potential therapeutic strategy for AML treatment.
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Affiliation(s)
- Guojin Wu
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Yixiang Xu
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX, USA
| | - Robbie D Schultz
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX, USA
| | - Heyu Chen
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Jingjing Xie
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Mi Deng
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Xiaoye Liu
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Xun Gui
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX, USA
| | - Samuel John
- Division of Pediatric Hematology- Oncology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Zhigang Lu
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390, USA
| | - Hisashi Arase
- Department of Immunochemistry, Research Institute for Microbial Diseases and Laboratory of Immunochemistry, World Premier International Immunology Frontier Research Center, Osaka University, Osaka, Japan
| | - Ningyan Zhang
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX, USA
| | - Zhiqiang An
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX, USA
| | - Cheng Cheng Zhang
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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2
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Arkee T, Bishop GA. TRAF family molecules in T cells: Multiple receptors and functions. J Leukoc Biol 2019; 107:907-915. [PMID: 31749173 DOI: 10.1002/jlb.2mr1119-397r] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/05/2019] [Accepted: 11/07/2019] [Indexed: 12/13/2022] Open
Abstract
The TNFR superfamily of receptors, the major focus of the recent TNFR Superfamily Conference held in June 2019, employ the TNFR-associated factor (TRAF) family of adaptor proteins in key aspects of their signaling pathways. Although many early studies investigated TRAF functions via exogenous overexpression in nonhematopoietic cell lines, it has subsequently become clear that whereas TRAFs share some overlap in function, each also plays unique biologic roles, that can be highly context dependent. This brief review summarizes the current state of knowledge of functions of each of the TRAF molecules that mediate important functions in T lymphocytes: TRAFs 1, 2, 3, 5, and 6. Due to our current appreciation of the contextual nature of TRAF function, our focus is upon findings made specifically in T lymphocytes. Key T cell functions for each TRAF are detailed, as well as future knowledge gaps of interest and importance.
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Affiliation(s)
- Tina Arkee
- Graduate Program in Immunology, The University of Iowa, Iowa City, Iowa, USA.,Medical Scientist Training Program, The University of Iowa, Iowa City, Iowa, USA
| | - Gail A Bishop
- Graduate Program in Immunology, The University of Iowa, Iowa City, Iowa, USA.,Medical Scientist Training Program, The University of Iowa, Iowa City, Iowa, USA.,Depts. of Microbiology & Immunology and Internal Medicine, The University of Iowa, Iowa City, Iowa, USA.,Iowa City VA Medical Center, Iowa City, Iowa, USA
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3
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Pedros C, Altman A, Kong KF. Role of TRAFs in Signaling Pathways Controlling T Follicular Helper Cell Differentiation and T Cell-Dependent Antibody Responses. Front Immunol 2018; 9:2412. [PMID: 30405612 PMCID: PMC6204373 DOI: 10.3389/fimmu.2018.02412] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 09/28/2018] [Indexed: 01/02/2023] Open
Abstract
Follicular helper T (TFH) cells represent a highly specialized CD4+ T cell subpopulation that supports the generation of germinal centers (GC) and provides B cells with critical signals promoting antibody class switching, generation of high affinity antibodies, and memory formation. TFH cells are characterized by the expression of the chemokine receptor CXCR5, the transcription factor Bcl-6, costimulatory molecules ICOS, and PD-1, and the production of cytokine IL-21. The acquisition of a TFH phenotype is a complex and multistep process that involves signals received through engagement of the TCR along with a multitude of costimulatory molecules and cytokines receptors. Members of the Tumor necrosis factor Receptor Associated Factors (TRAF) represent one of the major classes of signaling mediators involved in the differentiation and functions of TFH cells. TRAF molecules are the canonical adaptor molecules that physically interact with members of the Tumor Necrosis Factor Receptor Superfamily (TNFRSF) and actively modulate their downstream signaling cascades through their adaptor function and/or E3 ubiquitin ligase activity. OX-40, GITR, and 4-1BB are the TRAF-dependent TNFRSF members that have been implicated in the differentiation and functions of TFH cells. On the other hand, emerging data demonstrate that TRAF proteins also participate in signaling from the TCR and CD28, which deliver critical signals leading to the differentiation of TFH cells. More intriguingly, we recently showed that the cytoplasmic tail of ICOS contains a conserved TANK-binding kinase 1 (TBK1)-binding motif that is shared with TBK1-binding TRAF proteins. The presence of this TRAF-mimicking signaling module downstream of ICOS is required to mediate the maturation step during TFH differentiation. In addition, JAK-STAT pathways emanating from IL-2, IL-6, IL-21, and IL-27 cytokine receptors affect TFH development, and crosstalk between TRAF-mediated pathways and the JAK-STAT pathways can contribute to generate integrated signals required to drive and sustain TFH differentiation. In this review, we will introduce the molecular interactions and the major signaling pathways controlling the differentiation of TFH cells. In each case, we will highlight the contributions of TRAF proteins to these signaling pathways. Finally, we will discuss the role of individual TRAF proteins in the regulation of T cell-dependent humoral responses.
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Affiliation(s)
- Christophe Pedros
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, La Jolla, CA, United States
| | - Amnon Altman
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, La Jolla, CA, United States
| | - Kok-Fai Kong
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, La Jolla, CA, United States
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4
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Villanueva JE, Walters SN, Saito M, Malle EK, Zammit NW, Watson KA, Brink R, La Gruta NL, Alexander SI, Grey ST. Targeted deletion of Traf2 allows immunosuppression-free islet allograft survival in mice. Diabetologia 2017; 60:679-689. [PMID: 28062921 DOI: 10.1007/s00125-016-4198-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 12/05/2016] [Indexed: 01/04/2023]
Abstract
AIMS/HYPOTHESIS Administration of anti-CD40 ligand (CD40L) antibodies has been reported to allow long-term islet allograft survival in non-human primates without the need for exogenous immunosuppression. However, the use of anti-CD40L antibodies was associated with thromboembolic complications. Targeting downstream intracellular components shared between CD40 and other TNF family co-stimulatory molecules could bypass these complications. TNF receptor associated factor 2 (TRAF2) integrates multiple TNF receptor family signalling pathways that are critical for T cell activation and may be a central node of alloimmune responses. METHODS T cell-specific Traf2-deficient mice (Traf2TKO) were generated to define the role of TRAF2 in CD4+ T cell effector responses that mediate islet allograft rejection in vivo. In vitro allograft responses were tested using mixed lymphocyte reactions and analysis of IFN-γ and granzyme B effector molecule expression. T cell function was assessed using anti-CD3/CD28-mediated proliferation and T cell polarisation studies. RESULTS Traf2TKO mice exhibited permanent survival of full MHC-mismatched pancreatic islet allografts without exogenous immunosuppression. Traf2TKO CD4+ T cells exhibited reduced proliferation, activation and acquisition of effector function following T cell receptor stimulation; however, both Traf2TKO CD4+ and CD8+ T cells exhibited impaired alloantigen-mediated proliferation and acquisition of effector function. In polarisation studies, Traf2TKO CD4+ T cells preferentially converted to a T helper (Th)2 phenotype, but exhibited impaired Th17 differentiation. Without TRAF2, thymocytes exhibited dysregulated TNF-mediated induction of c-Jun N-terminal kinase (JNK) and canonical NFκB pathways. Critically, targeting TRAF2 in T cells did not impair the acute phase of CD8-dependent viral immunity. These data highlight a specific requirement for a TRAF2-NFκB and TRAF2-JNK signalling cascade in T cell activation and effector function in rejecting islet allografts. CONCLUSION/INTERPRETATION Targeting TRAF2 may be useful as a therapeutic approach for immunosuppression-free islet allograft survival that avoids the thromboembolic complications associated with the use of anti-CD40L antibodies.
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Affiliation(s)
- Jeanette E Villanueva
- Transplantation Immunology Group, Immunology Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW, 2010, Australia
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
| | - Stacey N Walters
- Transplantation Immunology Group, Immunology Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW, 2010, Australia
| | - Mitsuru Saito
- Centre for Kidney Research, Children's Hospital at Westmead, University of Sydney, Westmead, NSW, Australia
| | - Elisabeth K Malle
- Transplantation Immunology Group, Immunology Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW, 2010, Australia
| | - Nathan W Zammit
- Transplantation Immunology Group, Immunology Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW, 2010, Australia
| | - Katherine A Watson
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, VIC, Australia
- Immunology Division, The Walter and Eliza Hall Institute for Medical Research, Melbourne, VIC, Australia
| | - Robert Brink
- B Cell Biology Group, Immunology Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
| | - Nicole L La Gruta
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, VIC, Australia
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Stephen I Alexander
- Centre for Kidney Research, Children's Hospital at Westmead, University of Sydney, Westmead, NSW, Australia
| | - Shane T Grey
- Transplantation Immunology Group, Immunology Division, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW, 2010, Australia.
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5
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Waight JD, Gombos RB, Wilson NS. Harnessing co-stimulatory TNF receptors for cancer immunotherapy: Current approaches and future opportunities. Hum Antibodies 2017; 25:87-109. [PMID: 28085016 DOI: 10.3233/hab-160308] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Co-stimulatory tumor necrosis factor receptors (TNFRs) can sculpt the responsiveness of T cells recognizing tumor-associated antigens. For this reason, agonist antibodies targeting CD137, CD357, CD134 and CD27 have received considerable attention for their therapeutic utility in enhancing anti-tumor immune responses, particularly in combination with other immuno-modulatory antibodies targeting co-inhibitory pathways in T cells. The design of therapeutic antibodies that optimally engage and activate co-stimulatory TNFRs presents an important challenge of how to promote effective anti-tumor immunity while avoiding serious immune-related adverse events. Here we review our current understanding of the expression, signaling and structural features of CD137, CD357, CD134 and CD27, and how this may inform the design of pharmacologically active immuno-modulatory antibodies targeting these receptors. This includes the integration of our emerging knowledge of the role of Fcγ receptors (FcγRs) in facilitating antibody-mediated receptor clustering and forward signaling, as well as promoting immune effector cell-mediated activities. Finally, we bring our current preclinical and clinical knowledge of co-stimulatory TNFR antibodies into the context of opportunities for next generation molecules with improved pharmacologic properties.
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MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/immunology
- Antigens, Neoplasm/genetics
- Antigens, Neoplasm/immunology
- Antineoplastic Agents, Immunological/therapeutic use
- Gene Expression Regulation
- Humans
- Immunity, Cellular/drug effects
- Immunotherapy/methods
- Neoplasms/drug therapy
- Neoplasms/genetics
- Neoplasms/immunology
- Neoplasms/pathology
- Receptors, IgG/agonists
- Receptors, IgG/genetics
- Receptors, IgG/immunology
- Receptors, Tumor Necrosis Factor/agonists
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/immunology
- Signal Transduction
- T-Lymphocytes/drug effects
- T-Lymphocytes/immunology
- T-Lymphocytes/pathology
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6
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Walsh MC, Lee J, Choi Y. Tumor necrosis factor receptor- associated factor 6 (TRAF6) regulation of development, function, and homeostasis of the immune system. Immunol Rev 2016; 266:72-92. [PMID: 26085208 DOI: 10.1111/imr.12302] [Citation(s) in RCA: 292] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) is an adapter protein that mediates a wide array of protein-protein interactions via its TRAF domain and a RING finger domain that possesses non-conventional E3 ubiquitin ligase activity. First identified nearly two decades ago as a mediator of interleukin-1 receptor (IL-1R)-mediated activation of NFκB, TRAF6 has since been identified as an actor downstream of multiple receptor families with immunoregulatory functions, including members of the TNFR superfamily, the Toll-like receptor (TLR) family, tumor growth factor-β receptors (TGFβR), and T-cell receptor (TCR). In addition to NFκB, TRAF6 may also direct activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor pathways. In the context of the immune system, TRAF6-mediated signals have proven critical for the development, homeostasis, and/or activation of B cells, T cells, and myeloid cells, including macrophages, dendritic cells, and osteoclasts, as well as for organogenesis of thymic and secondary lymphoid tissues. In multiple cellular contexts, TRAF6 function is essential not only for proper activation of the immune system but also for maintaining immune tolerance, and more recent work has begun to identify mechanisms of contextual specificity for TRAF6, involving both regulatory protein interactions, and messenger RNA regulation by microRNAs.
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Affiliation(s)
- Matthew C Walsh
- Institute for Immunology and Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - JangEun Lee
- Institute for Immunology and Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Yongwon Choi
- Institute for Immunology and Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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7
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Giardino Torchia ML, Munitic I, Castro E, Herz J, McGavern DB, Ashwell JD. c-IAP ubiquitin protein ligase activity is required for 4-1BB signaling and CD8(+) memory T-cell survival. Eur J Immunol 2015; 45:2672-82. [PMID: 26096449 DOI: 10.1002/eji.201445342] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 05/28/2015] [Accepted: 06/17/2015] [Indexed: 11/10/2022]
Abstract
Cellular inhibitor of apoptosis proteins (c-IAP) 1 and 2 are widely expressed ubiquitin protein ligases that regulate a variety of cellular functions, including the sensitivity of T cells to costimulation. 4-1BB is a TNF receptor family member that signals via a complex that includes TRAF family members and the c-IAPs to upregulate NF-κB and ERK, and has been implicated in memory T-cell survival. Here, we show that effector and memory T cells from mice expressing a dominant negative E3-inactive c-IAP2 (c-IAP2(H570A)) have impaired signaling downstream of 4-1BB. When infected with lymphocytic choriomeningitis virus, unlike mice in which c-IAPs were acutely downregulated by c-IAP antagonists, the primary response of c-IAP2(H570A) mice was normal. However, the number of antigen-specific CD8(+) but not CD4(+) T cells declined more rapidly and to a greater extent in c-IAP2(H570A) mice than in WT controls. Studies with T-cell adoptive transfer demonstrated that the enhanced decay of memory cells was T-cell intrinsic. Thus, c-IAP E3 activity is required for 4-1BB coreceptor signaling and maintenance of CD8(+) T-cell memory.
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Affiliation(s)
| | - Ivana Munitic
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ehydel Castro
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jasmin Herz
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Dorian B McGavern
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Jonathan D Ashwell
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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8
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Villanueva JE, Malle EK, Gardam S, Silveira PA, Zammit NW, Walters SN, Brink R, Grey ST. TRAF2 regulates peripheral CD8(+) T-cell and NKT-cell homeostasis by modulating sensitivity to IL-15. Eur J Immunol 2015; 45:1820-31. [PMID: 25931426 DOI: 10.1002/eji.201445416] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/18/2015] [Accepted: 04/28/2015] [Indexed: 11/07/2022]
Abstract
In this study, a critical and novel role for TNF receptor (TNFR) associated factor 2 (TRAF2) is elucidated for peripheral CD8(+) T-cell and NKT-cell homeostasis. Mice deficient in TRAF2 only in their T cells (TRAF2TKO) show ∼40% reduction in effector memory and ∼50% reduction in naïve CD8(+) T-cell subsets. IL-15-dependent populations were reduced further, as TRAF2TKO mice displayed a marked ∼70% reduction in central memory CD8(+) CD44(hi) CD122(+) T cells and ∼80% decrease in NKT cells. TRAF2TKO CD8(+) CD44(hi) T cells exhibited impaired dose-dependent proliferation to exogenous IL-15. In contrast, TRAF2TKO CD8(+) T cells proliferated normally to anti-CD3 and TRAF2TKO CD8(+) CD44(hi) T cells exhibited normal proliferation to exogenous IL-2. TRAF2TKO CD8(+) T cells expressed normal levels of IL-15-associated receptors and possessed functional IL-15-mediated STAT5 phosphorylation, however TRAF2 deletion caused increased AKT activation. Loss of CD8(+) CD44(hi) CD122(+) and NKT cells was mechanistically linked to an inability to respond to IL-15. The reduced CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell populations in TRAF2TKO mice were rescued in the presence of high dose IL-15 by IL-15/IL-15Rα complex administration. These studies demonstrate a critical role for TRAF2 in the maintenance of peripheral CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell homeostasis by modulating sensitivity to T-cell intrinsic growth factors such as IL-15.
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Affiliation(s)
| | | | - Sandra Gardam
- B cell Biology Group, Immunology Division, Garvan Institute of Medical Research, Darlinghurst, Australia
| | | | | | | | - Robert Brink
- B cell Biology Group, Immunology Division, Garvan Institute of Medical Research, Darlinghurst, Australia
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9
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Martinez-Forero I, Azpilikueta A, Bolaños-Mateo E, Nistal-Villan E, Palazon A, Teijeira A, Perez-Chacon G, Morales-Kastresana A, Murillo O, Jure-Kunkel M, Zapata JM, Melero I. T cell costimulation with anti-CD137 monoclonal antibodies is mediated by K63-polyubiquitin-dependent signals from endosomes. THE JOURNAL OF IMMUNOLOGY 2013; 190:6694-706. [PMID: 23690480 DOI: 10.4049/jimmunol.1203010] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Agonist anti-CD137 (4-1BB) mAbs enhance CD8-mediated antitumor immunity. Agonist anti-human CD137 mAbs binding to four distinct epitopes on the CD137 glycoprotein costimulated T cell activation irrespective of the engaged epitope or its interference with CD137L binding. CD137 perturbation with all these agonist mAbs resulted in Ag and Ab internalization toward an endosomal vesicular compartment. Internalization was observed in activated T lymphocytes from humans and mice, not only in culture but also in Ab-injected living animals. These in vivo experiments were carried out upon systemic i.v. injections with anti-CD137 mAbs and showed CD137 internalization in tumor-infiltrating lymphocytes and in activated human T cells transferred to immunodeficient mice. Efficient CD137 internalization required K63 polyubiquitination and endocytosed CD137-containing vesicles recruited TNFR-associated factor (TRAF) 2 and were decorated with K63 polyubiquitins. CD137 stimulation activates NF-κB through a K63-linked polyubiquitination-dependent route, and CD137-associated TRAF2 becomes K63 polyubiquitinated. Consistent with a role for TRAF2 in CD137 signaling, transgenic mice functionally deficient in TRAF2 showed delayed immunotherapeutic activity of anti-CD137 mAbs. As a whole, these findings advance our knowledge of the mechanisms of action of anti-CD137 immunostimulatory mAbs such as those currently undergoing clinical trials in cancer patients.
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Affiliation(s)
- Ivan Martinez-Forero
- Centro de Investigación Médica Aplicada, Universidad de Navarra, Pamplona 31008, Spain
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10
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Zhang W, Zhang X, Wu XL, He LS, Zeng XF, Crammer AC, Lipsky PE. Competition between TRAF2 and TRAF6 regulates NF-kappaB activation in human B lymphocytes. ACTA ACUST UNITED AC 2010; 25:1-12. [PMID: 20449947 DOI: 10.1016/s1001-9294(10)60013-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To investigate the role of TNF receptor-associated factor 2 (TRAF-2) and TRAF6 in CD40-induced nuclear factor-kappaB (NF-kappaB) signaling pathway and whether CD40 signaling requires TRAF2. METHODS Human B cell lines were transfected with plasmids expressing wild type TRAF2 or dominant negative TRAF2, TRAF2-shRNA, or TRAF6-shRNA. The activation of NF-kappaB was detected by Western blot, kinase assay, transfactor enzyme-linked immunosorbent assay (ELISA), and fluorescence resonance energy transfer (FRET). Analysis of the role of TRAF-2 and TRAF-6 in CD40-mediated NF-kappaB activity was examined following stimulation with recombinant CD154. RESULTS TRAF2 induced activity of IkappaB-kinases (IKKalpha, IKKi/epsilon), phosphorylation of IkappaBalpha, as well as nuclear translocation and phosphorylation of p65/RelA. In contrast, TRAF6 strongly induced NF-kappaB activation and nuclear translocation of p65 as well as p50 and c-Rel. Engagement of CD154-induced nuclear translocation of p65 was inhibited by a TRAF6-shRNA, but conversely was enhanced by a TRAF2-shRNA. Examination of direct interactions between CD40 and TRAFs by FRET documented that both TRAF2 and TRAF6 directly interacted with CD40. However, the two TRAFs competed for CD40 binding. CONCLUSIONS These results indicate that TRAF2 can signal in human B cells, but it is not essential for CD40-mediated NF-kappaB activation. Moreover, TRAF2 can compete with TRAF6 for CD40 binding, and thereby limit the capacity of CD40 engagement to induce NF-kappaB activation.
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Affiliation(s)
- Wen Zhang
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, Intramural Research Program, National Institutes of Health, Bethesda, MD 20892, USA
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11
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Stemberger C, Neuenhahn M, Gebhardt FE, Schiemann M, Buchholz VR, Busch DH. Stem cell-like plasticity of naïve and distinct memory CD8+ T cell subsets. Semin Immunol 2009; 21:62-8. [PMID: 19269852 DOI: 10.1016/j.smim.2009.02.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Accepted: 02/04/2009] [Indexed: 12/18/2022]
Abstract
Most models regarding the 'clonal' origin of CD8(+) T cell effector and memory subset diversification suggest that during the first contact of a naïve T cell with the priming antigen-presenting cell major decisions for subsequent differentiation are made. Data using novel single-cell T cell tracking technologies demonstrate that a single naïve CD8(+) T cell can give rise to virtually all different subtypes of effector and memory T cells, and direct major determinants of subset diversification to the time period beyond the first cell division. Thereby, some 'stem cell-like' characteristics typical for naïve T cells are probably still maintained within distinct subsets of memory T cells. These observations have direct consequences for clinical applications like adoptive T cell therapy.
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Affiliation(s)
- Christian Stemberger
- Institute for Medical Microbiology, Immunology and Hygiene, Technical University Munich, Munich, Germany
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12
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Zapata JM, Lefebvre S, Reed JC. Targeting TRAFs for Therapeutic Intervention. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 597:188-201. [PMID: 17633027 DOI: 10.1007/978-0-387-70630-6_15] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
TNF-receptor associated factors (TRAFs) are the molecules that upon engagement of the TNF-receptor (TNFR) by a TNF-family ligand come first in contact with the activated TNFR, initially acting as docking molecules for kinases and other effector proteins that are recruited to the activated receptor. TRAFs later regulate the subcellular relocalization of the receptor-ligand complex and finally they modulate the extent of the response by controlling the degradation of key proteins in the pathway. In this chapter, we review the involvement of different TRAF family members in the etiology of a variety of pathologies and address the question of whether the use of TNFR-mimic-peptides or small molecule modulators targeting TRAFs might be suitable for therapeutic intervention, discussing the advantages and disadvantages of this strategy.
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Affiliation(s)
- Juan M Zapata
- Burnham Institute for Medical Research, La Jolla, California 92037, USA.
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13
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Richter MV, Topham DJ. The alpha1beta1 integrin and TNF receptor II protect airway CD8+ effector T cells from apoptosis during influenza infection. THE JOURNAL OF IMMUNOLOGY 2007; 179:5054-63. [PMID: 17911590 DOI: 10.4049/jimmunol.179.8.5054] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Primary viral infections of the lung induce potent effector CD8 T cell responses. To function in the influenza-infected airways, CD8 T cells must be able to resist cell death. The majority of the CD8 T cells in the airways and lung parenchyma expressed CD49a, the alpha-chain of the type IV collagen receptor VLA-1, and these cells were highly activated, producing both IFN-gamma and TNF-alpha. In the airways, where type IV collagen is abundant, but not the spleen, the CD49a(+) CD8 cells had reduced proportions of annexin V and caspase 8, and >80% expressed the TNF-alpha receptor II, while Fas, TNFR-I, and CD27 expression were similar to CD49a(-) cells. Furthermore, the CD49a(+), but not CD49a(-), CD8 T cells from the airways were resistant to active induction of apoptosis in the presence of type IV collagen and TNF-alpha in vitro. We propose that TNFR-II and the VLA-1 synergize to protect effector CD8 T cells in the infected airways from apoptosis during the acute infection.
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Affiliation(s)
- Martin V Richter
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14642, USA
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14
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Sabbagh L, Snell LM, Watts TH. TNF family ligands define niches for T cell memory. Trends Immunol 2007; 28:333-9. [PMID: 17597006 DOI: 10.1016/j.it.2007.06.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2007] [Revised: 05/29/2007] [Accepted: 06/13/2007] [Indexed: 01/23/2023]
Abstract
Immunological memory is a critical feature of the adaptive immune system and the underlying principal behind vaccination. The mechanisms that maintain memory T cell survival between the initial and subsequent encounter with antigen remain incompletely defined. Although the cytokines IL-15 and IL-7 are important in memory T cell homeostasis, additional signals by way of TNFR family members are required for maximal maintenance of T cell memory. Here we propose a unifying model in which subsets of TNF family ligands distinguish the competitive niches for maintenance of CD4 versus CD8 T cell memory. Understanding the unique 'memory niches' defined by TNF family ligand expression will provide new insights into the mechanisms of memory T cell maintenance.
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Affiliation(s)
- Laurent Sabbagh
- Department of Immunology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
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15
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Abstract
Transforming growth factor beta activated kinase-1 (TAK1), a member of the mitogen-activated protein kinase kinase kinase family, has emerged as a key regulator of signal transduction cascades leading to the activation of the transcription factors nuclear factor-kappa B (NF-kappaB) and activator protein-1 (AP-1). Stimulation of cells with cytokines and microbial pathogens results in the activation of TAK1, which subsequently activates the I-kappa B kinase complex (IKK) and mitogen-activated protein (MAP) kinases, culminating in the activation of NF-kappaB and AP-1, respectively. Recent studies have shown that polyubiquitination of signalling proteins through lysine (Lys)-63-linked polyubiquitin chains plays an important role in the activation of TAK1 and IKK. Unlike Lys-48-linked polyubiquitination, which normally targets proteins for degradation by the proteasome, Lys-63-linked polyubiquitin chains act as scaffolds to assemble protein kinase complexes and mediate their activation through proteasome-independent mechanisms. The concept of ubiquitin-mediated activation of protein kinases is supported by the discoveries of ubiquitination and deubiquitination enzymes as well as ubiquitin-binding proteins that function upstream of TAK1 and IKK. Recent biochemical and genetic studies provide further insights into the mechanism and function of ubiquitin signalling and these advances will be the focus of this review.
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Affiliation(s)
- A Adhikari
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
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16
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17
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Aspalter RM, Wolf HM, Eibl MM. Chronic TNF-α exposure impairs TCR-signaling via TNF-RII but not TNF-RI. Cell Immunol 2005; 237:55-67. [PMID: 16325164 DOI: 10.1016/j.cellimm.2005.10.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2005] [Revised: 10/04/2005] [Accepted: 10/19/2005] [Indexed: 01/13/2023]
Abstract
Chronic exposure to TNF-alpha has been shown to impair T cell-activation in mice and in humans. In the present study, we investigated a possible role of TNF-RII in this long-term effect of TNF-alpha. Chronic TNF-alpha exposure led to suppression of subsequent TCR stimulation (e.g., TCR/CD28-induced proliferation, cytokine production (IFN-gamma, TNF-alpha)) but left TCR independent restimulation unaffected. Activation of T cells during TNF-alpha exposure was required for the inhibitory effect on TCR stimulation. In contrast to the mouse model, the inhibitory effect of long-term TNF-alpha exposure was mediated via TNF-RII but not TNF-receptor I, and surface expression of the TCR/CD3 complex remained unchanged. Chronic TNF-RII triggering downregulated T cell activation at an early level, as TCR-induced calcium flux and IL-2 mRNA expression were impaired after preculture in the presence of anti-TNF-RII mAbs. Furthermore, chronic TNF-RII-stimulation specifically downregulated store operated calcium channels, which contribute to sustained TCR-induced calcium influx.
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Affiliation(s)
- Rosa M Aspalter
- Immunology Outpatient Clinic, Schwarzspanierstrasse 15/9/1, A-1090 Vienna, Austria
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18
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He L, Grammer AC, Wu X, Lipsky PE. TRAF3 forms heterotrimers with TRAF2 and modulates its ability to mediate NF-{kappa}B activation. J Biol Chem 2004; 279:55855-65. [PMID: 15383523 DOI: 10.1074/jbc.m407284200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
FRET experiments utilizing confocal microscopy or flow cytometry assessed homo- and heterotrimeric association of human tumor necrosis factor receptor-associated factors (TRAF) in living cells. Following transfection of HeLa cells with plasmids expressing CFP- or YFP-TRAF fusion proteins, constitutive homotypic association of TRAF2, -3, and -5 was observed, as well as heterotypic association of TRAF1-TRAF2 and TRAF3-TRAF5. A novel heterotypic association between TRAF2 and -3 was detected and confirmed by immunoprecipitation in Ramos B cells that constitutively express both TRAF2 and -3. Experiments employing deletion mutants of TRAF2 and TRAF3 revealed that this heterotypic interaction minimally involved the TRAF-C domain of TRAF3 as well as the TRAF-N domain and zinc fingers 4 and 5 of TRAF2. A novel flow cytometric FRET analysis utilizing a two-step approach to achieve linked FRET from CFP to YFP to HcRed established that TRAF2 and -3 constitutively form homo- and heterotrimers. The functional importance of TRAF2-TRAF3 heterotrimerization was demonstrated by the finding that TRAF3 inhibited spontaneous NF-kappaB, but not AP-1, activation induced by TRAF2. Ligation of CD40 on Ramos B cells by recombinant CD154 caused TRAF2 and TRAF3 to dissociate, whereas overexpression of TRAF3 in Ramos B cells inhibited CD154-induced TRAF2-mediated activation of NF-kappaB. Together, these results reveal a novel association between TRAF2 and TRAF3 that is mediated by unique portions of each protein and that specifically regulates activation of NF-kappaB, but not AP-1.
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Affiliation(s)
- Liusheng He
- Flow Cytometry Section in the Office of Science and Technology, National Institute of Arthritis and Musculoskeletal and Skin Diseases/NIH, 9000 Rockville Pike, Building 10, Bethesda, MD 20892, USA
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19
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Sun L, Deng L, Ea CK, Xia ZP, Chen ZJ. The TRAF6 ubiquitin ligase and TAK1 kinase mediate IKK activation by BCL10 and MALT1 in T lymphocytes. Mol Cell 2004; 14:289-301. [PMID: 15125833 DOI: 10.1016/s1097-2765(04)00236-9] [Citation(s) in RCA: 550] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2004] [Revised: 03/29/2004] [Accepted: 04/13/2004] [Indexed: 01/18/2023]
Abstract
The CARD domain protein BCL10 and paracaspase MALT1 are essential for the activation of IkappaB kinase (IKK) and NF-kappaB in response to T cell receptor (TCR) stimulation. Here we present evidence that TRAF6 ubiquitin ligase and TAK1 protein kinase mediate IKK activation by BCL10 and MALT1. RNAi-mediated silencing of MALT1, TAK1, TRAF6, and TRAF2 suppressed TCR-dependent IKK activation and interleukin-2 production in T cells. Furthermore, we have reconstituted the pathway from BCL10 to IKK activation in vitro with purified proteins of MALT1, TRAF6, TAK1, and ubiquitination enzymes including Ubc13/Uev1A. We find that a small fraction of BCL10 and MALT1 proteins form high molecular weight oligomers. Strikingly, only these oligomeric forms of BCL10 and MALT1 can activate IKK in vitro. The MALT1 oligomers bind to TRAF6, induce TRAF6 oligomerization, and activate the ligase activity of TRAF6 to polyubiquitinate NEMO. These results reveal an oligomerization --> ubiquitination --> phosphorylation cascade that culminates in NF-kappaB activation in T lymphocytes.
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Affiliation(s)
- Lijun Sun
- Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
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20
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Weinberg AD, Evans DE, Thalhofer C, Shi T, Prell RA. The generation of T cell memory: a review describing the molecular and cellular events following OX40 (CD134) engagement. J Leukoc Biol 2004; 75:962-72. [PMID: 14996827 DOI: 10.1189/jlb.1103586] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OX40 (CD134), a membrane-bound member of the tumor necrosis factor-receptor superfamily, is expressed primarily on activated CD4(+) T cells. Following engagement on the cell surface, OX40 delivers a costimulatory signal that leads to potent, proinflammatory effects. Engagement of OX40 during antigen (Ag)-specific stimulation of T cells leads to increased production of memory T cells, increased migration of Ag-specific T cells, enhanced cytokine production by effector T cells, and the ability to break peripheral T cell tolerance in vivo. Therefore, OX40 engagement in vivo could have important ramifications for the enhancement of vaccine strategies and inhibition of unwanted inflammation. This review summarizes the molecular and cellular events that occur following OX40 engagement during Ag-specific T cell activation.
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Affiliation(s)
- Andrew D Weinberg
- Earle A. Chiles Research Institute, Robert W. Franz Cancer Research Center, Providence Portland Medical Center, 4805 N.E. Glisan, Portland, OR 97213, USA.
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21
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Prell RA, Evans DE, Thalhofer C, Shi T, Funatake C, Weinberg AD. OX40-mediated memory T cell generation is TNF receptor-associated factor 2 dependent. THE JOURNAL OF IMMUNOLOGY 2004; 171:5997-6005. [PMID: 14634111 DOI: 10.4049/jimmunol.171.11.5997] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Tumor necrosis factor receptor-associated factor 2 (TRAF2), an adapter protein that associates with the cytoplasmic tail of OX40, may play a critical role in OX40-mediated signal transduction. To investigate the in vivo role of TRAF2 in OX40-mediated generation of Ag-specific memory T cells, we bred OVA-specific TCR transgenic mice to TRAF2 dominant-negative (TRAF2 DN) mice. Following Ag stimulation and OX40 engagement of TRAF2 DN T cells in vivo, the number of long-lived OVA-specific T cells and effector T cell function was dramatically reduced when compared with wild-type T cells. We also demonstrate that CTLA-4 is down-regulated following OX40 engagement in vivo and the OX40-specific TRAF2 DN defect was partially overcome by CTLA-4 blockade in vivo. The data provide evidence that TRAF2 is linked to OX40-mediated memory T cell expansion and survival, and point to the down-regulation of CTLA-4 as a possible control element to enhance early T cell expansion through OX40 signaling.
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MESH Headings
- Adoptive Transfer
- Animals
- Antigens, CD
- Antigens, Differentiation/biosynthesis
- Antigens, Differentiation/physiology
- CTLA-4 Antigen
- Cell Division/immunology
- Cells, Cultured
- Epitopes, T-Lymphocyte/immunology
- Growth Inhibitors/biosynthesis
- Growth Inhibitors/physiology
- Immune Sera/administration & dosage
- Immunologic Memory
- Lymph Nodes/cytology
- Lymph Nodes/immunology
- Lymph Nodes/metabolism
- Lymphocyte Activation/immunology
- Lymphocyte Subsets/immunology
- Lymphocyte Subsets/metabolism
- Mice
- Mice, Inbred BALB C
- Mice, Transgenic
- Oligonucleotide Array Sequence Analysis
- Ovalbumin/administration & dosage
- Ovalbumin/immunology
- Ovalbumin/pharmacology
- Protein Biosynthesis
- Proteins/genetics
- Proteins/physiology
- RNA/isolation & purification
- Receptors, OX40
- Receptors, Tumor Necrosis Factor/antagonists & inhibitors
- Receptors, Tumor Necrosis Factor/immunology
- Receptors, Tumor Necrosis Factor/metabolism
- Receptors, Tumor Necrosis Factor/physiology
- Signal Transduction/genetics
- Signal Transduction/immunology
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/transplantation
- TNF Receptor-Associated Factor 2
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Affiliation(s)
- Rodney A Prell
- Earle A. Chiles Research Institute, Robert W. Franz Cancer Research Center, Providence Portland Medical Center, Portland, OR 97213, USA
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22
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Abstract
MHC class I tetramer staining, intracellular cytokine staining and ELISPOT assays have made it possible to quantify CD8(+) T-cell responses precisely during and following viral and bacterial infection. Although these quantitative methods are by now familiar and trusted components of the immunologist's toolbox, their application to models of microbial infection continues to provide surprising insights into mammalian adaptive immunity. In the past year there have been many exciting new findings on CD8(+) T-cell priming, expansion and memory formation in response to microbial infection.
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Affiliation(s)
- Natalya Serbina
- Infectious Diseases Service, Memorial Sloan-Kettering Cancer Center, Immunology Program, Sloan-Kettering Institute, New York 10021, USA.
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23
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Abstract
Interactions between co-stimulatory ligands and their receptors are crucial for the activation of T cells, the prevention of tolerance and the development of T-cell immunity. It is now evident that members of the immunoglobulin-like CD28-B7 co-stimulatory family cannot fully account for an effective long-lasting T-cell response or the generation of memory T cells. Several members of the tumour-necrosis factor receptor (TNFR) superfamily--OX40, 4-1BB, CD27, CD30 and HVEM (herpes-virus entry mediator)--are poised to deliver co-stimulatory signals both early and late after encounter with antigen. The roles of these molecules in initiating and sustaining the T-cell response and in promoting long-lived immunity are discussed.
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Affiliation(s)
- Michael Croft
- Division of Molecular Immunology, La Jolla Institute for Allergy and Immunology, San Diego, California 92121, USA.
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24
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Abstract
TNF-receptor-associated factors (TRAFs) are the bottleneck of the TNF-receptor (TNF-R) family signal transduction. They integrate the signalling from many members of the TNF-R family and initiate intracellular signalling cascades aimed at the activation of NF-kappaB and c-jun, the reprogramming of gene expression and the control of cell death. Deregulation of these pathways is the cause of several autoimmune and inflammatory diseases. The specificity and interaction of the members of the TRAF family with the TNF-R entails the recognition of just a 4 - 6 amino acid motif in the cytosolic region of the receptor, suitable as an attractive target for drug discovery. This review summarises the current knowledge on TRAFs and discusses the pros and cons of their application as targets for drug discovery.
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Affiliation(s)
- Juan M Zapata
- The Burnham Institute, 10901 N. Torrey Pines Road, La Jolla, CA 92037, USA.
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