1
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Kunkl M, Amormino C, Spallotta F, Caristi S, Fiorillo MT, Paiardini A, Kaempfer R, Tuosto L. Bivalent binding of staphylococcal superantigens to the TCR and CD28 triggers inflammatory signals independently of antigen presenting cells. Front Immunol 2023; 14:1170821. [PMID: 37207220 PMCID: PMC10189049 DOI: 10.3389/fimmu.2023.1170821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 04/21/2023] [Indexed: 05/21/2023] Open
Abstract
Staphylococcus aureus superantigens (SAgs) such as staphylococcal enterotoxin A (SEA) and B (SEB) are potent toxins stimulating T cells to produce high levels of inflammatory cytokines, thus causing toxic shock and sepsis. Here we used a recently released artificial intelligence-based algorithm to better elucidate the interaction between staphylococcal SAgs and their ligands on T cells, the TCR and CD28. The obtained computational models together with functional data show that SEB and SEA are able to bind to the TCR and CD28 stimulating T cells to activate inflammatory signals independently of MHC class II- and B7-expressing antigen presenting cells. These data reveal a novel mode of action of staphylococcal SAgs. By binding to the TCR and CD28 in a bivalent way, staphylococcal SAgs trigger both the early and late signalling events, which lead to massive inflammatory cytokine secretion.
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Affiliation(s)
- Martina Kunkl
- Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University, Rome, Italy
| | - Carola Amormino
- Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University, Rome, Italy
| | - Francesco Spallotta
- Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University, Rome, Italy
- Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Silvana Caristi
- Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University, Rome, Italy
| | - Maria Teresa Fiorillo
- Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University, Rome, Italy
| | - Alessandro Paiardini
- Department of Biochemical Sciences “A. Rossi Fanelli”, Sapienza University of Rome, Rome, Italy
| | - Raymond Kaempfer
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Loretta Tuosto
- Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University, Rome, Italy
- Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
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2
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SARS-CoV-2 Spike Does Not Possess Intrinsic Superantigen-like Inflammatory Activity. Cells 2022; 11:cells11162526. [PMID: 36010602 PMCID: PMC9406418 DOI: 10.3390/cells11162526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 08/12/2022] [Indexed: 11/24/2022] Open
Abstract
Multisystem inflammatory syndrome in children (MIS-C) is a rare hyperinflammatory disease occurring several weeks after SARS-CoV-2 infection. The clinical similarities between MIS-C and the toxic shock syndrome, together with the preferential expansion of T cells with a T-cell receptor variable β chain (TCRVβ) skewing, suggested a superantigen theory of MIS-C. For instance, recent in silico modelling evidenced the presence of a highly conserved motif within SARS-CoV-2 spike protein similar in structure to the superantigenic fragment of staphylococcal enterotoxin B (SEB). However, experimental data on the superantigenic activity of the SARS-CoV-2 spike have not yet been provided. Here, we assessed the superantigenic activity of the SARS-CoV-2 spike by analysing inflammatory cytokine production in both Jurkat cells and the peripheral blood CD4+ T cells stimulated with the SARS-CoV-2 spike or SEB as a control. We found that, unlike SEB, the SARS-CoV-2 spike does not exhibit an intrinsic superantigen-like activity.
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3
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Zhou J, Chen J, Huang Y, Gao X, Zhou C, Meng X, Sun J. Signaling Dynamics of TSHR-Specific CAR-T Cells Revealed by FRET-Based Biosensors. Front Cell Dev Biol 2022; 10:845319. [PMID: 35252208 PMCID: PMC8893275 DOI: 10.3389/fcell.2022.845319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 01/31/2022] [Indexed: 12/05/2022] Open
Abstract
Although most patients with thyroid cancers have good prognosis and long-term survival, some patients are refractory to traditional therapeutic approaches and face a high risk of mortality. CAR-T therapy provides an attractive strategy to treat these patients. Considering the limited expression in thyroid tissues, thyroid-stimulating hormone receptor (TSHR) has been considered as a promising candidate as CAR-T target. However, it is still a challenge to find the optimal CAR design for the treatment of thyroid cancers. Dynamic signaling cascade is initiated by CAR molecules during CAR-T cell activation. The development of FRET-based biosensors enables us to detect the signaling dynamics of key kinases during CAR-T cell activation with high spatiotemporal resolution. Here using the ZAP70 and ERK biosensors, we visualized the dynamics of ZAP70 and ERK activities in TSHR-specific CAR-T cells upon antigen stimulation. We first constructed several TSHR-targeting CARs for the treatment of advanced thyroid cancers. The TSHR CAR-T cells with CD28 or 4-1BB co-stimulatory signaling domains exhibited potent cytotoxicity in vitro. By FRET imaging, we observed rapid increase of ZAP70 and ERK activities in TSHR CAR-T cells upon target cell binding. Even though CD28-based CAR-T cells had similar ZAP70 activation dynamics as 4-1BB-based CAR-T cells, they displayed slightly enhanced ERK activation, which may contribute to their faster anti-tumor kinetics in vivo. These results demonstrated the efficacy of TSHR CAR-T cells to treat advanced thyroid cancers. Our study indicated the potential of applying FRET biosensors to optimize the design of CAR for effective CAR-T therapy.
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Affiliation(s)
- Jing Zhou
- Department of Breast and Thyroid Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Department of Breast and Thyroid Surgery, People’s Hospital of Dongxihu District Wuhan City and Union Dongxihu Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Jiangqing Chen
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China
- Department of Cell Biology, Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Institute of Hematology, Zhejiang University and Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, China
| | - Yanjie Huang
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, China
| | - Xiaofei Gao
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, China
| | - Chun Zhou
- School of Public Health, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xianhui Meng
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China
- Department of Cell Biology, Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Institute of Hematology, Zhejiang University and Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, China
- *Correspondence: Xianhui Meng, ; Jie Sun,
| | - Jie Sun
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China
- Department of Cell Biology, Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Institute of Hematology, Zhejiang University and Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, China
- *Correspondence: Xianhui Meng, ; Jie Sun,
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4
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Kunkl M, Amormino C, Caristi S, Tedeschi V, Fiorillo MT, Levy R, Popugailo A, Kaempfer R, Tuosto L. Binding of Staphylococcal Enterotoxin B (SEB) to B7 Receptors Triggers TCR- and CD28-Mediated Inflammatory Signals in the Absence of MHC Class II Molecules. Front Immunol 2021; 12:723689. [PMID: 34489975 PMCID: PMC8418141 DOI: 10.3389/fimmu.2021.723689] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/02/2021] [Indexed: 01/19/2023] Open
Abstract
The inflammatory activity of staphylococcal enterotoxin B (SEB) relies on its capacity to trigger polyclonal T-cell activation by binding both T-cell receptor (TCR) and costimulatory receptor CD28 on T cells and MHC class II and B7 molecules on antigen presenting cells (APC). Previous studies highlighted that SEB may bind TCR and CD28 molecules independently of MHC class II, yet the relative contribution of these interactions to the pro-inflammatory function of SEB remained unclear. Here, we show that binding to MHC class II is dispensable for the inflammatory activity of SEB, whereas binding to TCR, CD28 and B7 molecules is pivotal, in both human primary T cells and Jurkat T cell lines. In particular, our finding is that binding of SEB to B7 molecules suffices to trigger both TCR- and CD28-mediated inflammatory signalling. We also provide evidence that, by strengthening the interaction between CD28 and B7, SEB favours the recruitment of the TCR into the immunological synapse, thus inducing lethal inflammatory signalling.
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Affiliation(s)
- Martina Kunkl
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Carola Amormino
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Silvana Caristi
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Valentina Tedeschi
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy
| | - Maria Teresa Fiorillo
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy
| | - Revital Levy
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Andrey Popugailo
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Raymond Kaempfer
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Loretta Tuosto
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
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5
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Martínez-Méndez D, Villarreal C, Mendoza L, Huerta L. An Integrative Network Modeling Approach to T CD4 Cell Activation. Front Physiol 2020; 11:380. [PMID: 32425809 PMCID: PMC7212416 DOI: 10.3389/fphys.2020.00380] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 03/30/2020] [Indexed: 12/15/2022] Open
Abstract
The adaptive immune response is initiated by the interaction of the T cell antigen receptor/CD3 complex (TCR) with a cognate peptide bound to a MHC molecule. This interaction, along with the activity of co-stimulatory molecules and cytokines in the microenvironment, enables cells to proliferate and produce soluble factors that stimulate other branches of the immune response for inactivation of infectious agents. The intracellular activation signals are reinforced, amplified and diversified by a complex network of biochemical interactions, and includes the activity of molecules that modulate the activation process and stimulate the metabolic changes necessary for fulfilling the cell energy demands. We present an approach to the analysis of the main early signaling events of T cell activation by proposing a concise 46-node hybrid Boolean model of the main steps of TCR and CD28 downstream signaling, encompassing the activity of the anergy factor Ndrg1, modulation of activation by CTLA-4, and the activity of the nutrient sensor AMPK as intrinsic players of the activation process. The model generates stable states that reflect the overcoming of activation signals and induction of anergy by the expression of Ndrg1 in the absence of co-stimulation. The model also includes the induction of CTLA-4 upon activation and its competition with CD28 for binding to the co-stimulatory CD80/86 molecules, leading to stable states that reflect the activation arrest. Furthermore, the model integrates the activity of AMPK to the general pathways driving differentiation to functional cell subsets (Th1, Th2, Th17, and Treg). Thus, the network topology incorporates basic mechanism associated to activation, regulation and induction of effector cell phenotypes. The model puts forth a conceptual framework for the integration of functionally relevant processes in the analysis of the T CD4 cell function.
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Affiliation(s)
- David Martínez-Méndez
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Carlos Villarreal
- Instituto de Física, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Luis Mendoza
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Leonor Huerta
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico
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6
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Beyond the Cell Surface: Targeting Intracellular Negative Regulators to Enhance T cell Anti-Tumor Activity. Int J Mol Sci 2019; 20:ijms20235821. [PMID: 31756921 PMCID: PMC6929154 DOI: 10.3390/ijms20235821] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 11/04/2019] [Accepted: 11/07/2019] [Indexed: 02/07/2023] Open
Abstract
It is well established that extracellular proteins that negatively regulate T cell function, such as Cytotoxic T-Lymphocyte-Associated protein 4 (CTLA-4) and Programmed Cell Death protein 1 (PD-1), can be effectively targeted to enhance cancer immunotherapies and Chimeric Antigen Receptor T cells (CAR-T cells). Intracellular proteins that inhibit T cell receptor (TCR) signal transduction, though less well studied, are also potentially useful therapeutic targets to enhance T cell activity against tumor. Four major classes of enzymes that attenuate TCR signaling include E3 ubiquitin kinases such as the Casitas B-lineage lymphoma proteins (Cbl-b and c-Cbl), and Itchy (Itch), inhibitory tyrosine phosphatases, such as Src homology region 2 domain-containing phosphatases (SHP-1 and SHP-2), inhibitory protein kinases, such as C-terminal Src kinase (Csk), and inhibitory lipid kinases such as Src homology 2 (SH2) domain-containing inositol polyphosphate 5-phosphatase (SHIP) and Diacylglycerol kinases (DGKs). This review describes the mechanism of action of eighteen intracellular inhibitory regulatory proteins in T cells within these four classes, and assesses their potential value as clinical targets to enhance the anti-tumor activity of endogenous T cells and CAR-T cells.
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7
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Tang R, Langdon WY, Zhang J. Regulation of immune responses by E3 ubiquitin ligase Cbl-b. Cell Immunol 2018; 340:103878. [PMID: 30442330 DOI: 10.1016/j.cellimm.2018.11.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/04/2018] [Accepted: 11/05/2018] [Indexed: 12/21/2022]
Abstract
Casitas B lymphoma-b (Cbl-b), a RING finger E3 ubiquitin ligase, has been identified as a critical regulator of adaptive immune responses. Cbl-b is essential for establishing the threshold for T cell activation and regulating peripheral T cell tolerance through various mechanisms. Intriguingly, recent studies indicate that Cbl-b also modulates innate immune responses, and plays a key role in host defense to pathogens and anti-tumor immunity. These studies suggest that targeting Cbl-b may represent a potential therapeutic strategy for the management of human immune-related disorders such as autoimmune diseases, infections, tumors, and allergic airway inflammation. In this review, we summarize the latest developments regarding the roles of Cbl-b in innate and adaptive immunity, and immune-mediated diseases.
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Affiliation(s)
- Rong Tang
- Department of Nephrology, Xiangya Hospital, Central South University, Changsha, Hunan, PR China
| | - Wallace Y Langdon
- School of Biological Sciences, University of Western Australia, Perth, Australia
| | - Jian Zhang
- Department of Pathology, The University of Iowa, Iowa City, IA, USA.
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8
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Del Río-Iñiguez I, Vázquez-Chávez E, Cuche C, Di Bartolo V, Bouchet J, Alcover A. HIV-1 Nef Hijacks Lck and Rac1 Endosomal Traffic To Dually Modulate Signaling-Mediated and Actin Cytoskeleton-Mediated T Cell Functions. THE JOURNAL OF IMMUNOLOGY 2018; 201:2624-2640. [PMID: 30282749 DOI: 10.4049/jimmunol.1800372] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 09/03/2018] [Indexed: 01/03/2023]
Abstract
Endosomal traffic of TCR and signaling molecules regulates immunological synapse formation and T cell activation. We recently showed that Rab11 endosomes regulate the subcellular localization of the tyrosine kinase Lck and of the GTPase Rac1 and control their functions in TCR signaling and actin cytoskeleton remodeling. HIV-1 infection of T cells alters their endosomal traffic, activation capacity, and actin cytoskeleton organization. The viral protein Nef is pivotal for these modifications. We hypothesized that HIV-1 Nef could jointly alter Lck and Rac1 endosomal traffic and concomitantly modulate their functions. In this study, we show that HIV-1 infection of human T cells sequesters both Lck and Rac1 in a pericentrosomal compartment in an Nef-dependent manner. Strikingly, the Nef-induced Lck compartment contains signaling-competent forms (phosphorylated on key Tyr residues) of Lck and some of its downstream effectors, TCRζ, ZAP70, SLP76, and Vav1, avoiding the proximal LAT adaptor. Importantly, Nef-induced concentration of signaling molecules was concomitant with the upregulation of several early and late T cell activation genes. Moreover, preventing the concentration of the Nef-induced Lck compartment by depleting the Rab11 effector FIP3 counteracted Nef-induced gene expression upregulation. In addition, Nef extensively sequesters Rac1 and downregulates Rac1-dependent actin cytoskeleton remodeling, thus reducing T cell spreading. Therefore, by modifying their endosomal traffic, Nef hijacks signaling and actin cytoskeleton regulators to dually modulate their functional outputs. Our data shed new light into the molecular mechanisms that modify T cell physiology during HIV-1 infection.
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Affiliation(s)
- Iratxe Del Río-Iñiguez
- Lymphocyte Cell Biology Unit, Department of Immunology, Institut Pasteur, 75724 Paris, France.,INSERM U1221, 75015 Paris, France; and.,Collège Doctoral, Sorbonne Université, 75014 Paris, France
| | - Elena Vázquez-Chávez
- Lymphocyte Cell Biology Unit, Department of Immunology, Institut Pasteur, 75724 Paris, France.,INSERM U1221, 75015 Paris, France; and
| | - Céline Cuche
- Lymphocyte Cell Biology Unit, Department of Immunology, Institut Pasteur, 75724 Paris, France.,INSERM U1221, 75015 Paris, France; and
| | - Vincenzo Di Bartolo
- Lymphocyte Cell Biology Unit, Department of Immunology, Institut Pasteur, 75724 Paris, France.,INSERM U1221, 75015 Paris, France; and
| | - Jérôme Bouchet
- Lymphocyte Cell Biology Unit, Department of Immunology, Institut Pasteur, 75724 Paris, France; .,INSERM U1221, 75015 Paris, France; and
| | - Andrés Alcover
- Lymphocyte Cell Biology Unit, Department of Immunology, Institut Pasteur, 75724 Paris, France; .,INSERM U1221, 75015 Paris, France; and
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9
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Taylor A, Rudd CE. Glycogen Synthase Kinase 3 Inactivation Compensates for the Lack of CD28 in the Priming of CD8 + Cytotoxic T-Cells: Implications for anti-PD-1 Immunotherapy. Front Immunol 2017; 8:1653. [PMID: 29312284 PMCID: PMC5732207 DOI: 10.3389/fimmu.2017.01653] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Accepted: 11/13/2017] [Indexed: 01/23/2023] Open
Abstract
The rescue of exhausted CD8+ cytolytic T-cells (CTLs) by anti-Programmed Cell Death-1 (anti-PD-1) blockade has been found to require CD28 expression. At the same time, we have shown that the inactivation of the serine/threonine kinase glycogen synthase kinase (GSK)-3α/β with small-interfering RNAs (siRNAs) and small molecule inhibitors (SMIs) specifically down-regulates PD-1 expression for enhanced CD8+ CTL function and clearance of tumors and viral infections. Despite this, it has been unclear whether the GSK-3α/β pathway accounts for CD28 costimulation of CD8+ CTL function. In this article, we show that inactivation of GSK-3α/β through siRNA or by SMIs during priming can substitute CD28 co-stimulation in the potentiation of cytotoxic CD8+ CTL function against the EL-4 lymphoma cells expressing OVA peptide. The effect was seen using several structurally distinct GSK-3 SMIs and was accompanied by an increase in Lamp-1 and GZMB expression. Conversely, CD28 crosslinking obviated the need for GSK-3α/β inhibition in its enhancement of CTL function. Our findings support a model where GSK-3 is the central cosignal for CD28 priming of CD8+ CTLs in anti-PD-1 immunotherapy.
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Affiliation(s)
- Alison Taylor
- Leeds Institute of Cancer and Pathology (LICAP), University of Leeds, St James's University Hospital, Leeds, United Kingdom
| | - Christopher E Rudd
- Division of Immunology-Oncology Research Center, Maisonneuve-Rosemont Hospital, Montreal, QC, Canada.,Département de Médecine, Université de Montréal, Montreal, QC, Canada.,Department of Pathology, Cell Signalling Section, Cambridge University, Cambridge, United Kingdom.,Immune Venture Ltd., London, United Kingdom
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10
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Porciello N, Kunkl M, Viola A, Tuosto L. Phosphatidylinositol 4-Phosphate 5-Kinases in the Regulation of T Cell Activation. Front Immunol 2016; 7:186. [PMID: 27242793 PMCID: PMC4865508 DOI: 10.3389/fimmu.2016.00186] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/02/2016] [Indexed: 11/21/2022] Open
Abstract
Phosphatidylinositol 4,5-biphosphate kinases (PIP5Ks) are critical regulators of T cell activation being the main enzymes involved in the synthesis of phosphatidylinositol 4,5-biphosphate (PIP2). PIP2 is indeed a pivotal regulator of the actin cytoskeleton, thus controlling T cell polarization and migration, stable adhesion to antigen-presenting cells, spatial organization of the immunological synapse, and co-stimulation. Moreover, PIP2 also serves as a precursor for the second messengers inositol triphosphate, diacylglycerol, and phosphatidylinositol 3,4,5-triphosphate, which are essential for the activation of signaling pathways regulating cytokine production, cell cycle progression, survival, metabolism, and differentiation. Here, we discuss the impact of PIP5Ks on several T lymphocyte functions with a specific focus on the role of CD28 co-stimulation in PIP5K compartimentalization and activation.
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Affiliation(s)
- Nicla Porciello
- Department of Biology and Biotechnology Charles Darwin, Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza University , Rome , Italy
| | - Martina Kunkl
- Department of Biology and Biotechnology Charles Darwin, Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy; Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Antonella Viola
- Department of Biomedical Sciences, University of Padua, Padua, Italy; Venetian Institute of Molecular Medicine (VIMM), Padua, Italy
| | - Loretta Tuosto
- Department of Biology and Biotechnology Charles Darwin, Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza University , Rome , Italy
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11
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Porciello N, Tuosto L. CD28 costimulatory signals in T lymphocyte activation: Emerging functions beyond a qualitative and quantitative support to TCR signalling. Cytokine Growth Factor Rev 2016; 28:11-9. [PMID: 26970725 DOI: 10.1016/j.cytogfr.2016.02.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 02/22/2016] [Indexed: 01/22/2023]
Abstract
CD28 is one of the most important co-stimulatory receptors necessary for full T lymphocyte activation. By binding its cognate ligands, B7.1/CD80 or B7.2/CD86, expressed on the surface of professional antigen presenting cells (APC), CD28 initiates several signalling cascades, which qualitatively and quantitatively support T cell receptor (TCR) signalling. More recent data evidenced that human CD28 can also act as a TCR-independent signalling unit, by delivering specific signals, which regulate the expression of pro-inflammatory cytokine/chemokines. Despite the enormous progresses made in identifying the mechanisms and molecules involved in CD28 signalling properties, much remains to be elucidated, especially in the light of the functional differences observed between human and mouse CD28. In this review we provide an overview of the current mechanisms and molecules through which CD28 support TCR signalling and highlight recent findings on the specific signalling motifs that regulate the unique pro-inflammatory activity of human CD28.
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Affiliation(s)
- Nicla Porciello
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, 00185 Rome, Italy
| | - Loretta Tuosto
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, 00185 Rome, Italy.
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12
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Kallikourdis M, Trovato AE, Roselli G, Muscolini M, Porciello N, Tuosto L, Viola A. Phosphatidylinositol 4-Phosphate 5-Kinase β Controls Recruitment of Lipid Rafts into the Immunological Synapse. THE JOURNAL OF IMMUNOLOGY 2016; 196:1955-63. [PMID: 26773155 DOI: 10.4049/jimmunol.1501788] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 12/17/2015] [Indexed: 11/19/2022]
Abstract
Phosphatidylinositol 4,5-biphosphate (PIP2) is critical for T lymphocyte activation serving as a substrate for the generation of second messengers and the remodeling of actin cytoskeleton necessary for the clustering of lipid rafts, TCR, and costimulatory receptors toward the T:APC interface. Spatiotemporal analysis of PIP2 synthesis in T lymphocytes suggested that distinct isoforms of the main PIP2-generating enzyme, phosphatidylinositol 4-phosphate 5-kinase (PIP5K), play a differential role on the basis of their distinct localization. In this study, we analyze the contribution of PIP5Kβ to T cell activation and show that CD28 induces the recruitment of PIP5Kβ to the immunological synapse, where it regulates filamin A and lipid raft accumulation, as well as T cell activation, in a nonredundant manner. Finally, we found that Vav1 and the C-terminal 83 aa of PIP5Kβ are pivotal for the PIP5Kβ regulatory functions in response to CD28 stimulation.
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Affiliation(s)
- Marinos Kallikourdis
- Humanitas University, Rozzano, Milan 20089, Italy; Adaptive Immunity Laboratory, Humanitas Clinical and Research Center, Rozzano, Milan 20089, Italy
| | - Anna Elisa Trovato
- Adaptive Immunity Laboratory, Humanitas Clinical and Research Center, Rozzano, Milan 20089, Italy
| | - Giuliana Roselli
- Adaptive Immunity Laboratory, Humanitas Clinical and Research Center, Rozzano, Milan 20089, Italy
| | - Michela Muscolini
- Pasteur Institute-Cenci Bolognetti Foundation, Department of Biology and Biotechnology Charles Darwin, Sapienza University, 00185 Rome, Italy; and
| | - Nicla Porciello
- Pasteur Institute-Cenci Bolognetti Foundation, Department of Biology and Biotechnology Charles Darwin, Sapienza University, 00185 Rome, Italy; and
| | - Loretta Tuosto
- Pasteur Institute-Cenci Bolognetti Foundation, Department of Biology and Biotechnology Charles Darwin, Sapienza University, 00185 Rome, Italy; and
| | - Antonella Viola
- Department of Biomedical Sciences, University of Padua and Venetian Institute of Molecular Medicine, 35131 Padua, Italy
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13
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Gardner DH, Jeffery LE, Soskic B, Briggs Z, Hou TZ, Raza K, Sansom DM. 1,25(OH)2D3 Promotes the Efficacy of CD28 Costimulation Blockade by Abatacept. THE JOURNAL OF IMMUNOLOGY 2015; 195:2657-65. [PMID: 26276872 PMCID: PMC4560489 DOI: 10.4049/jimmunol.1500306] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 07/22/2015] [Indexed: 02/03/2023]
Abstract
Inhibition of the CD28:CD80/CD86 T cell costimulatory pathway has emerged as an effective strategy for the treatment of T cell–mediated inflammatory diseases. However, patient responses to CD28-ligand blockade by abatacept (CTLA-4-Ig) in conditions such as rheumatoid arthritis are variable and often suboptimal. In this study, we show that the extent to which abatacept suppresses T cell activation is influenced by the strength of TCR stimulation, with high-strength TCR stimulation being associated with relative abatacept insensitivity. Accordingly, cyclosporin A, an inhibitor of T cell stimulation via the TCR, synergized with abatacept to inhibit T cell activation. We also observed that 1,25-dihydroxyvitamin D3 enhanced the inhibition of T cell activation by abatacept, strongly inhibiting T cell activation driven by cross-linked anti-CD3, but with no effect upon anti-CD28 driven stimulation. Thus, like cyclosporin A, 1,25-dihydroxyvitamin D3 inhibits TCR-driven activation, thereby promoting abatacept sensitivity. Vitamin D3 supplementation may therefore be a useful adjunct for the treatment of conditions such as rheumatoid arthritis in combination with abatacept to promote the efficacy of treatment.
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Affiliation(s)
- David H Gardner
- Medical Research Council Centre for Immune Regulation, School of Immunity and Infection, Institute of Biomedical Research, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Louisa E Jeffery
- Medical Research Council Centre for Immune Regulation, School of Immunity and Infection, Institute of Biomedical Research, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Blagoje Soskic
- Institute of Immunity and Transplantation, University College London and Royal Free Hospital, London NW3 2PF, United Kingdom; and
| | - Zoe Briggs
- Medical Research Council Centre for Immune Regulation, School of Immunity and Infection, Institute of Biomedical Research, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Tie Zheng Hou
- Institute of Immunity and Transplantation, University College London and Royal Free Hospital, London NW3 2PF, United Kingdom; and
| | - Karim Raza
- Medical Research Council Centre for Immune Regulation, School of Immunity and Infection, Institute of Biomedical Research, University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Rheumatology, Sandwell and West Birmingham Hospitals National Health Service Trust, Birmingham B18 7QH, United Kingdom
| | - David M Sansom
- Institute of Immunity and Transplantation, University College London and Royal Free Hospital, London NW3 2PF, United Kingdom; and
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14
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Cotta-de-Almeida V, Dupré L, Guipouy D, Vasconcelos Z. Signal Integration during T Lymphocyte Activation and Function: Lessons from the Wiskott-Aldrich Syndrome. Front Immunol 2015; 6:47. [PMID: 25709608 PMCID: PMC4321635 DOI: 10.3389/fimmu.2015.00047] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 01/26/2015] [Indexed: 11/18/2022] Open
Abstract
Over the last decades, research dedicated to the molecular and cellular mechanisms underlying primary immunodeficiencies (PID) has helped to understand the etiology of many of these diseases and to develop novel therapeutic approaches. Beyond these aspects, PID are also studied because they offer invaluable natural genetic tools to dissect the human immune system. In this review, we highlight the research that has focused over the last 20 years on T lymphocytes from Wiskott–Aldrich syndrome (WAS) patients. WAS T lymphocytes are defective for the WAS protein (WASP), a regulator of actin cytoskeleton remodeling. Therefore, study of WAS T lymphocytes has helped to grasp that many steps of T lymphocyte activation and function depend on the crosstalk between membrane receptors and the actin cytoskeleton. These steps include motility, immunological synapse assembly, and signaling, as well as the implementation of helper, regulatory, or cytotoxic effector functions. The recent concept that WASP also works as a regulator of transcription within the nucleus is an illustration of the complexity of signal integration in T lymphocytes. Finally, this review will discuss how further study of WAS may contribute to solve novel challenges of T lymphocyte biology.
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Affiliation(s)
| | - Loïc Dupré
- UMR 1043, Centre de Physiopathologie de Toulouse Purpan, INSERM , Toulouse , France ; Université Toulouse III Paul-Sabatier , Toulouse , France ; UMR 5282, CNRS , Toulouse , France
| | - Delphine Guipouy
- UMR 1043, Centre de Physiopathologie de Toulouse Purpan, INSERM , Toulouse , France ; Université Toulouse III Paul-Sabatier , Toulouse , France ; UMR 5282, CNRS , Toulouse , France
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15
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Muscolini M, Camperio C, Porciello N, Caristi S, Capuano C, Viola A, Galandrini R, Tuosto L. Phosphatidylinositol 4–Phosphate 5–Kinase α and Vav1 Mutual Cooperation in CD28-Mediated Actin Remodeling and Signaling Functions. THE JOURNAL OF IMMUNOLOGY 2015; 194:1323-1333. [DOI: 10.4049/jimmunol.1401643] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Abstract
Phosphatidylinositol 4,5–biphosphate (PIP2) is a cell membrane phosphoinositide crucial for cell signaling and activation. Indeed, PIP2 is a pivotal source for second messenger generation and controlling the activity of several proteins regulating cytoskeleton reorganization. Despite its critical role in T cell activation, the molecular mechanisms regulating PIP2 turnover remain largely unknown. In human primary CD4+ T lymphocytes, we have recently demonstrated that CD28 costimulatory receptor is crucial for regulating PIP2 turnover by allowing the recruitment and activation of the lipid kinase phosphatidylinositol 4–phosphate 5–kinase (PIP5Kα). We also identified PIP5Kα as a key modulator of CD28 costimulatory signals leading to the efficient T cell activation. In this study, we extend these data by demonstrating that PIP5Kα recruitment and activation is essential for CD28-mediated cytoskeleton rearrangement necessary for organizing a complete signaling compartment leading to downstream signaling functions. We also identified Vav1 as the linker molecule that couples the C-terminal proline-rich motif of CD28 to the recruitment and activation of PIP5Kα, which in turn cooperates with Vav1 in regulating actin polymerization and CD28 signaling functions.
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Affiliation(s)
- Michela Muscolini
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
| | - Cristina Camperio
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
| | - Nicla Porciello
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
| | - Silvana Caristi
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
| | - Cristina Capuano
- †Department of Experimental Medicine, Sapienza University, 00185 Rome, Italy
| | - Antonella Viola
- ‡The Venetian Institute of Molecular Medicine, Padova 35129, Italy; and
- §Department of Biomedical Sciences, University of Padova, Padova 35121, Italy
| | | | - Loretta Tuosto
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
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16
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Jain N, Miu B, Jiang JK, McKinstry KK, Prince A, Swain SL, Greiner DL, Thomas CJ, Sanderson MJ, Berg LJ, Kang J. CD28 and ITK signals regulate autoreactive T cell trafficking. Nat Med 2013; 19:1632-7. [PMID: 24270545 PMCID: PMC4005518 DOI: 10.1038/nm.3393] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Accepted: 10/04/2013] [Indexed: 01/07/2023]
Abstract
Activation of self-reactive T cells and their trafficking to target tissues leads to autoimmune organ destruction. Mice lacking the co-inhibitory receptor cytotoxic T lymphocyte antigen-4 (CTLA-4) develop fatal autoimmunity characterized by lymphocytic infiltration into nonlymphoid tissues. Here, we demonstrate that the CD28 co-stimulatory pathway regulates the trafficking of self-reactive Ctla4(-/-) T cells to tissues. Concurrent ablation of the CD28-activated Tec family kinase ITK does not block spontaneous T cell activation but instead causes self-reactive Ctla4(-/-) T cells to accumulate in secondary lymphoid organs. Despite excessive spontaneous T cell activation and proliferation in lymphoid organs, Itk(-/-); Ctla4(-/-) mice are otherwise healthy, mount antiviral immune responses and exhibit a long lifespan. We propose that ITK specifically licenses autoreactive T cells to enter tissues to mount destructive immune responses. Notably, ITK inhibitors mimic the null mutant phenotype and also prevent pancreatic islet infiltration by diabetogenic T cells in mouse models of type 1 diabetes, highlighting their potential utility for the treatment of human autoimmune disorders.
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Affiliation(s)
- Nitya Jain
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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17
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Abstract
Anergy is a long-term stable state of T-lymphocyte unresponsiveness to antigenic stimulation associated with the blockade of IL-2 production and proliferation. Anergy is a pathway of peripheral tolerance formation. In this review, mechanisms underlying T-cell tolerization are considered in a classical in vitro model of clonal anergy, and these mechanisms are compared with different pathways of anergy induction in vivo. Special attention is given to regulatory T-lymphocytes because, on one hand, anergy is a specific feature of these cells, and on the other hand anergy is also a mechanism of their action on target cells - effector T-lymphocytes. The role of this phenomenon in the differentiation of regulatory T-cells and also in the development of activation-induced apoptosis in effector T-lymphocytes is discussed.
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Affiliation(s)
- E M Kuklina
- Institute of Ecology and Genetics of Microorganisms, Ural Branch of the Russian Academy of Sciences, 614081 Perm, Russia.
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18
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Ksionda O, Saveliev A, Köchl R, Rapley J, Faroudi M, Smith-Garvin JE, Wülfing C, Rittinger K, Carter T, Tybulewicz VLJ. Mechanism and function of Vav1 localisation in TCR signalling. J Cell Sci 2012; 125:5302-14. [PMID: 22956543 PMCID: PMC3561853 DOI: 10.1242/jcs.105148] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The antigen-specific binding of T cells to antigen presenting cells results in recruitment of signalling proteins to microclusters at the cell-cell interface known as the immunological synapse (IS). The Vav1 guanine nucleotide exchange factor plays a critical role in T cell antigen receptor (TCR) signalling, leading to the activation of multiple pathways. We now show that it is recruited to microclusters and to the IS in primary CD4+ and CD8+ T cells. Furthermore, we show that this recruitment depends on the SH2 and C-terminal SH3 (SH3B) domains of Vav1, and on phosphotyrosines 112 and 128 of the SLP76 adaptor protein. Biophysical measurements show that Vav1 binds directly to these residues on SLP76 and that efficient binding depends on the SH2 and SH3B domains of Vav1. Finally, we show that the same two domains are critical for the phosphorylation of Vav1 and its signalling function in TCR-induced calcium flux. We propose that Vav1 is recruited to the IS by binding to SLP76 and that this interaction is critical for the transduction of signals leading to calcium flux.
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Affiliation(s)
- Olga Ksionda
- Division of Immune Cell Biology, MRC National Institute for Medical Research, London NW7 1AA, UK
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19
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Isakov N, Altman A. PKC-theta-mediated signal delivery from the TCR/CD28 surface receptors. Front Immunol 2012; 3:273. [PMID: 22936936 PMCID: PMC3425079 DOI: 10.3389/fimmu.2012.00273] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 08/09/2012] [Indexed: 12/23/2022] Open
Abstract
Protein kinase C-theta (PKCθ) is a key enzyme in T lymphocytes, where it plays an important role in signal transduction downstream of the activated T cell antigen receptor (TCR) and the CD28 costimulatory receptor. Interest in PKCθ as a potential drug target has increased following recent findings that PKCθ is essential for harmful inflammatory responses mediated by Th2 (allergies) and Th17 (autoimmunity) cells as well as for graft-versus-host disease (GvHD) and allograft rejection, but is dispensable for beneficial responses such as antiviral immunity and graft-versus-leukemia (GvL) response. TCR/CD28 engagement triggers the translocation of the cytosolic PKCθ to the plasma membrane (PM), where it localizes at the center of the immunological synapse (IS), which forms at the contact site between an antigen-specific T cell and antigen-presenting cells (APC). However, the molecular basis for this unique localization, and whether it is required for its proper function have remained unresolved issues until recently. Our recent study resolved these questions by demonstrating that the unique V3 (hinge) domain of PKCθ and, more specifically, a proline-rich motif within this domain, is essential and sufficient for its localization at the IS, where it is anchored to the cytoplasmic tail of CD28 via an indirect mechanism involving Lck protein tyrosine kinase (PTK) as an intermediate. Importantly, the association of PKCθ with CD28 is essential not only for IS localization, but also for PKCθ-mediated activation of downstream signaling pathways, including the transcription factors NF-κB and NF-AT, which are essential for productive T cell activation. Hence, interference with formation of the PKCθ-Lck-CD28 complex provides a promising basis for the design of novel, clinically useful allosteric PKCθ inhibitors. An additional recent study demonstrated that TCR triggering activates the germinal center kinase (GSK)-like kinase (GLK) and induces its association with the SLP-76 adaptor at the IS, where GLK phosphorylates the activation loop of PKCθ, converting it into an active enzyme. This recent progress, coupled with the need to study the biology of PKCθ in human T cells, is likely to facilitate the development of PKCθ-based therapeutic modalities for T cell-mediated diseases.
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Affiliation(s)
- Noah Isakov
- The Shraga Segal Department of Microbiology and Immunology, Faculty of Health Sciences and the Cancer Research Center, Ben-Gurion University of the Negev Beer Sheva, Israel
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20
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Haubert D, Li J, Saveliev A, Calzascia T, Sutter E, Metzler B, Kaiser D, Tybulewicz VL, Weckbecker G. Vav1 GEF activity is required for T cell mediated allograft rejection. Transpl Immunol 2012; 26:212-9. [PMID: 22456277 PMCID: PMC3485565 DOI: 10.1016/j.trim.2012.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 03/09/2012] [Accepted: 03/09/2012] [Indexed: 11/30/2022]
Abstract
The GDP exchange factor (GEF) Vav1 is a central signal transducer downstream of the T cell receptor and has been identified as a key factor for T cell activation in the context of allograft rejection. Vav1 has been shown to transduce signals both dependent and independent of its GEF function. The most promising approach to disrupt Vav1 activity by pharmacological inhibition would be to target its GEF function. However, the contribution of Vav1 GEF activity for allogeneic T cell activation has not been clarified yet. To address this question, we used knock-in mice bearing a mutated Vav1 with disrupted GEF activity but intact GEF-independent functions. T cells from these mice showed strongly reduced proliferation and activation in response to allogeneic stimulation. Furthermore, lack of Vav1 GEF activity strongly abrogated the in vivo expansion of T cells in a systemic graft-versus-host model. In a cardiac transplantation model, mice with disrupted Vav1 GEF activity show prolonged allograft survival. These findings demonstrate a strong requirement for Vav1 GEF activity for allogeneic T cell activation and graft rejection suggesting that disruption of Vav1 GEF activity alone is sufficient to induce significant immunosuppression.
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Affiliation(s)
- Dirk Haubert
- Novartis Institutes of BioMedical Research, Autoimmunity, Transplantation & Inflammation, 4002 Basel, Switzerland
| | - Jianping Li
- Novartis Institutes of BioMedical Research, Autoimmunity, Transplantation & Inflammation, 4002 Basel, Switzerland
| | - Alexander Saveliev
- Division of Immune Cell Biology, MRC National Institute for Medical Research, London NW7 1AA, UK
| | - Thomas Calzascia
- Novartis Institutes of BioMedical Research, Autoimmunity, Transplantation & Inflammation, 4002 Basel, Switzerland
| | - Esther Sutter
- Novartis Institutes of BioMedical Research, Autoimmunity, Transplantation & Inflammation, 4002 Basel, Switzerland
| | - Barbara Metzler
- Novartis Institutes of BioMedical Research, Autoimmunity, Transplantation & Inflammation, 4002 Basel, Switzerland
| | - Daniel Kaiser
- Novartis Institutes of BioMedical Research, Autoimmunity, Transplantation & Inflammation, 4002 Basel, Switzerland
| | - Victor L.J. Tybulewicz
- Division of Immune Cell Biology, MRC National Institute for Medical Research, London NW7 1AA, UK
| | - Gisbert Weckbecker
- Novartis Institutes of BioMedical Research, Autoimmunity, Transplantation & Inflammation, 4002 Basel, Switzerland
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21
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Tuosto L. NF-κB family of transcription factors: Biochemical players of CD28 co-stimulation. Immunol Lett 2011; 135:1-9. [DOI: 10.1016/j.imlet.2010.09.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 09/09/2010] [Accepted: 09/14/2010] [Indexed: 12/31/2022]
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22
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Riha P, Rudd CE. CD28 co-signaling in the adaptive immune response. SELF NONSELF 2010; 1:231-240. [PMID: 21487479 DOI: 10.4161/self.1.3.12968] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 07/12/2010] [Indexed: 12/20/2022]
Abstract
T-cell proliferation and function depends on signals from the antigen-receptor complex (TCR/CD3) and by various co-receptors such as CD28 and CTLA-4. The balance of positive and negative signals determines the outcome of the T-cell response to foreign and self-antigen. CD28 is a prominent co-receptor in naïve and memory T-cell responses. Its blockade has been exploited clinically to dampen T-cell responses to self-antigen. Current evidence shows that CD28 both potentiates TCR signaling and engages a unique array of mediators (PI3K, Grb2, FLNa) in the regulation of aspects of T-cell signaling including the transcription factor NFkB. In this mini-review, we provide an up-to-date overview of our understanding of the signaling mechanisms that underlie CD28 function and its potential application to the modulation of reactivity to autoimmunity.
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Affiliation(s)
- Pavel Riha
- Cell Signaling Section; Department of Pathology; University of Cambridge; Cambridge, UK
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23
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Abstract
CD28 costimulation regulates a wide range of cellular processes, from proliferation and survival to promoting the differentiation of specialized T-cell subsets. Since first being identified over 20 years ago, CD28 has remained a subject of intense study because of its profound consequences on T cell function and its potential for therapeutic manipulation. In this review we highlight the signaling cascades initiated by the major signaling motifs in CD28, focusing on PI-3 kinase-dependent and -independent pathways and how these are linked to specific cellular outcomes. Recent studies using gene targeted knockin mice have clarified the relative importance of these motifs on in vivo immune responses; however, much remains to be elucidated. Understanding the mechanism behind costimulation holds great potential for development of new clinically relevant reagents, a fact beginning to be realized with the advent of drugs that prevent CD28 ligation and signaling.
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Affiliation(s)
- Jonathan S Boomer
- Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA
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24
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Zhang Z, Rosenbaum JT, Zhong W, Lim C, Hinrichs DJ. Costimulation of Th17 cells: Adding fuel or putting out the fire in the inflamed gut? Semin Immunopathol 2010; 32:55-70. [PMID: 20119686 DOI: 10.1007/s00281-009-0190-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Accepted: 12/21/2009] [Indexed: 12/15/2022]
Abstract
Inflammatory bowel disease, typified by Crohn's disease and ulcerative colitis, is a common disorder characterized by recurrent and serious inflammation of the gastrointestinal tract. It is well documented that T cells play a pivotal role in the development of inflammatory bowel disease. Th17 cells are a unique T cell subpopulation implicated in inflammatory bowel disease and many other autoimmune/inflammatory diseases. However, the regulatory mechanism of Th17 activation and proliferation has not been defined completely. Recent studies have shown that the ligation of several costimulatory receptor-ligand pairs contributes to the activation, differentiation, and proliferation of T lymphocytes including the Th17 subset. In this review, we will discuss the emerging evidence on the role of Th17 cells in inflammatory bowel disease pathogenesis as well as the effect of costimulatory molecules on Th17 development and consider if the need for such costimulation of T lymphocytes provides a target for the development of novel therapeutic strategy.
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Affiliation(s)
- Zili Zhang
- Department of Pediatrics, Oregon Health & Science University, Portland, 97239, USA.
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25
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Abstract
SUMMARY T-cell activation is mediated by antigen-specific signals from the TCRzeta/CD3 and CD4-CD8-p56lck complexes in combination with additional co-signals provided by coreceptors such as CD28, inducible costimulator (ICOS), cytotoxic T-lymphocyte antigen-4 (CTLA-4), programmed death (PD-1), and others. CD28 and ICOS provide positive signals that promote and sustain T-cell responses, while CTLA-4 and PD-1 limit responses. The balance between stimulatory and inhibitory co-signals determines the ultimate nature of T-cell responses where response to foreign pathogen is achieved without excess inflammation and autoimmunity. In this review, we outline the current knowledge of the CD28 and CTLA-4 signaling mechanisms [involving phosphatidylinositol 3 kinase (PI3K), growth factor receptor-bound protein 2 (Grb2), Filamin A, protein kinase C theta (PKCtheta), and phosphatases] that control T-cell immunity. We also present recent findings on T-cell receptor-interacting molecule (TRIM) regulation of CTLA-4 surface expression, and a signaling pathway involving CTLA-4 activation of PI3K and protein kinase B (PKB)/AKT by which cell survival is ensured under conditions of anergy induction.
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Affiliation(s)
- Christopher E Rudd
- Department of Pathology, Cell Signalling Section, University of Cambridge, Cambridge, UK.
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26
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Zhan Y, Davey GM, Graham KL, Kiu H, Dudek NL, Kay TWH, Lew AM. SOCS1 negatively regulates the production of Foxp3+ CD4+ T cells in the thymus. Immunol Cell Biol 2009; 87:473-80. [PMID: 19381159 DOI: 10.1038/icb.2009.23] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
SOCS1 profoundly influences the development and peripheral homeostasis of CD8+ T cells but has less impact on CD4+ T cells. Despite the moderate influence of SOCS1 in the development of the total CD4 T-cell lineage, we show here that SOCS1 deficiency resulted in a 10-fold increase in Foxp3(+) CD4(+) T cells in the thymus. Increased numbers of Foxp3+ thymocytes occurred in mice with T-cell-specific ablation of SOCS1, suggesting that the effect is T-cell intrinsic. This increase in Foxp3+ CD4+cells in SOCS1-deficient mice also occurred in the absence of IFN-gamma or/and IL-7 signaling. Increase in CD25+CD4+ T cells in the absence of SOCS1 could be partly due to enhanced survival by CD25+CD4+cells, to a lesser degree CD25-CD4+ T cells, from SOCS1-deficient mice with or without T-cell growth factors.
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Affiliation(s)
- Yifan Zhan
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Victoria 3050, Australia.
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27
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Abstract
CD28 is recognized as the primary costimulatory molecule involved in the activation of naïve T cells. However, the biochemical signaling pathways that are activated by CD28 and how these pathways are integrated with TCR signaling are still not understood. We have recently shown that there are at least two independent activation pathways induced by CD28 costimulation. One is integrated with TCR signaling in the context of the immunological synapse and is mediated through transcriptional enhancement and the second is mediated through the induction of mRNA stability. Here, we review the immunological consequences and biochemical mechanisms associated with CD28 costimulation and discuss the major questions that need to be resolved to understand the molecular mechanisms that transduce CD28 costimulation.
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28
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Abstract
T-cell activation and differentiation depend on the signal strength received by the T-cell receptor and on signals provided by co-stimulatory molecules. The most prominent co-stimulatory molecule is CD28, which controls the activation of naïve and memory T cells by antigen presented on professional antigen-presenting cells. Blocking of the CD28-CD80/86 pathway has been an appealing strategy for inducing tolerance in autoimmune diseases where the disease-inducing autoantigens are not known. Although CD28 has maintained its unique position, the past decade has witnessed the recognition that a large number of regulatory molecules on T cells must be stimulated to generate a fully protective immune response. These regulatory receptors differ in their preferential expression on T-cell subsets, in the ligands that they recognize, and in the signaling pathways that they trigger. They have in common the fact that they provide information on the cellular environment in which the T-cell response occurs. By intercepting these signals, we may be able to influence disease-relevant T-cell responses in autoimmune diseases while potentially minimizing broad immunosuppression.
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Affiliation(s)
- Jörg J Goronzy
- Kathleen B and Mason I Lowance Center for Human Immunology and Rheumatology, Emory University, Woodruff Circle, Atlanta, Georgia 30322, USA.
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29
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Abstract
T cell cytoarchitecture differs dramatically depending on whether the cell is circulating within the bloodstream, migrating through tissues, or interacting with antigen-presenting cells. The transition between these states requires important signaling-dependent changes in actin cytoskeletal dynamics. Recently, analysis of actin-regulatory proteins associated with T cell activation has provided new insights into how T cells control actin dynamics in response to external stimuli and how actin facilitates downstream signaling events and effector functions. Among the actin-regulatory proteins that have been identified are nucleation-promoting factors such as WASp, WAVE2, and HS1; severing proteins such as cofilin; motor proteins such as myosin II; and linker proteins such as ezrin and moesin. We review the current literature on how signaling pathways leading from diverse cell surface receptors regulate the coordinated activity of these and other actin-regulatory proteins and how these proteins control T cell function.
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Affiliation(s)
- Janis K Burkhardt
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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30
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Jacobs SR, Herman CE, Maciver NJ, Wofford JA, Wieman HL, Hammen JJ, Rathmell JC. Glucose uptake is limiting in T cell activation and requires CD28-mediated Akt-dependent and independent pathways. THE JOURNAL OF IMMUNOLOGY 2008; 180:4476-86. [PMID: 18354169 DOI: 10.4049/jimmunol.180.7.4476] [Citation(s) in RCA: 605] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
T cell activation potently stimulates cellular metabolism to support the elevated energetic and biosynthetic demands of growth, proliferation, and effector function. We show that glucose uptake is limiting in T cell activation and that CD28 costimulation is required to allow maximal glucose uptake following TCR stimulation by up-regulating expression and promoting the cell surface trafficking of the glucose transporter Glut1. Regulation of T cell glucose uptake and Glut1 was critical, as low glucose prevented appropriate T cell responses. Additionally, transgenic expression of Glut1 augmented T cell activation, and led to accumulation of readily activated memory-phenotype T cells with signs of autoimmunity in aged mice. To further examine the regulation of glucose uptake, we analyzed CD28 activation of Akt, which appeared necessary for maximal glucose uptake of stimulated cells and which we have shown can promote Glut1 cell surface trafficking. Consistent with a role for Akt in Glut1 trafficking, transgenic expression of constitutively active myristoylated Akt increased glucose uptake of resting T cells, but did not alter Glut1 protein levels. Therefore, CD28 appeared to promote Akt-independent up-regulation of Glut1 and Akt-dependent Glut1 cell surface trafficking. In support of this model, coexpression of Glut1 and myristoylated Akt transgenes resulted in a synergistic increase in glucose uptake and accumulation of activated T cells in vivo that were largely independent of CD28. Induction of Glut1 protein and Akt regulation of Glut1 trafficking are therefore separable functions of CD28 costimulation that cooperate to promote glucose metabolism for T cell activation and proliferation.
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Affiliation(s)
- Sarah R Jacobs
- Department of Pharmacology and Cancer Biology, Sarah W Stedman Center for Nutrition and Metabolism, Duke University Medical Center, Durham, NC 27710, USA
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Schneider H, Rudd CE. CD28 and Grb-2, relative to Gads or Grap, preferentially co-operate with Vav1 in the activation of NFAT/AP-1 transcription. Biochem Biophys Res Commun 2008; 369:616-21. [PMID: 18295596 PMCID: PMC4186964 DOI: 10.1016/j.bbrc.2008.02.068] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Accepted: 02/14/2008] [Indexed: 12/11/2022]
Abstract
The co-receptor CD28 binds to several intracellular proteins including PI3 kinase, Grb-2, Gads and ITK. Grb-2 and PI3 kinase binding has been mapped to the pYMNM motif within the cytoplasmic tail of CD28 and has been shown to play a role in co-stimulation. In this study, we demonstrate that amongst the Grb-2 family adapter proteins, CD28 precipitated Grb-2 and specifically co-operated in the up-regulation of NFAT/AP-1 transcription. By contrast, Gads and Grap either failed or only weakly collaborated with CD28 ligation. Further, the loss of Grb-2 binding interferes with the ability of Vav1 to co-operate with CD28. Anti-CD28 ligation alone was capable for co-operating with Grb-2 or Grb-2-Vav1. Our findings define a pathway involving CD28 binding to Grb-2 and its co-operativity with Vav1 in the regulation of T-cell co-stimulation.
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Affiliation(s)
- Helga Schneider
- Cell Signalling Section, Division of Immunology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Christopher E. Rudd
- Cell Signalling Section, Division of Immunology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
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Abstract
Migration of primed T-cells to the antigenic site is an essential event in the development of effective immunity. This process is tightly regulated in order to ensure efficient and specific responses. Most studies have focused on non-specific mediators of T-cell migration, including integrins and chemokines. However, recent studies have highlighted the key role of the T-cell receptor and co-stimulatory molecules in guiding T-cell access to antigenic tissue. Here, we review the experimental evidence for an essential contribution of co-stimulation-mediated molecular interactions regulating T-cell migration in the development of T-cell immunity and tolerance.
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T-cell receptor-induced NF-kappaB activation is negatively regulated by E3 ubiquitin ligase Cbl-b. Mol Cell Biol 2008; 28:2470-80. [PMID: 18227156 DOI: 10.1128/mcb.01505-07] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
It has previously been shown that E3 ubiquitin ligase Casitas B-lineage lymphoma-b (Cbl-b) negatively regulates T-cell activation, but the molecular mechanism(s) underlying this inhibition is not completely defined. In this study, we report that the loss of Cbl-b selectively results in aberrant activation of NF-kappaB upon T-cell antigen receptor (TCR) ligation, which is mediated by phosphatidylinositol 3-kinase (PI3-K)/Akt and protein kinase C-theta (PKC-theta). TCR-induced hyperactivation of Akt in the absence of Cbl-b may potentiate the formation of caspase recruitment domain-containing membrane-associated guanylate kinase protein 1 (CARMA1)-B-cell lymphoma/leukemia 10 (Bcl10)-mucosa-associated lymphatic tissue 1(MALT1) (CBM) complex, which appears to be independent of PKC-theta. Cbl-b associates with PKC-theta upon TCR stimulation and regulates TCR-induced PKC-theta activation via Vav-1, which couples PKC-theta to PI3-K and allows it to be phosphorylated. PKC-theta then couples IkappaB kinases (IKKs) to the CBM complex, resulting in the activation of the IKK complex. Therefore, our data provide the first evidence to demonstrate that the down-regulation of TCR-induced NF-kappaB activation by Cbl-b is mediated coordinately by both Akt-dependent and PKC-theta-dependent signaling pathways in primary T cells.
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Cronin SJF, Penninger JM. From T-cell activation signals to signaling control of anti-cancer immunity. Immunol Rev 2008; 220:151-68. [PMID: 17979845 DOI: 10.1111/j.1600-065x.2007.00570.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The activation of resting T cells is crucial to most immune processes. Recognition of foreign antigen by T-cell receptors has to be correctly translated into signal transduction events necessary for the induction of an effective immune response. In this review, we discuss the essential signals, molecules, and processes necessary to achieve full T-cell activation. In addition to describing these key biological events, we also discuss how T-cell receptor signaling may be harnessed to yield new therapeutic targets for a next generation of anti-cancer drugs.
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Affiliation(s)
- Shane J F Cronin
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
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Katzav S. Flesh and blood: The story of Vav1, a gene that signals in hematopoietic cells but can be transforming in human malignancies. Cancer Lett 2007; 255:241-54. [PMID: 17590270 DOI: 10.1016/j.canlet.2007.04.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 04/30/2007] [Accepted: 04/30/2007] [Indexed: 01/08/2023]
Abstract
Cancer results from the interaction of multiple aberrations including activation of dominant oncogenes and upregulation of signal transduction pathways. Identification of the genes involved in malignant transformation is a pre-requisite for understanding cancer and improving its diagnosis and treatment. Quite a few of the genes that have been implicated in cancer are mutant or aberrantly expressed versions of genes that are important mediators of the normal growth that occurs during development. An important example of this is Vav1, a cytoplasmic signal transducer protein initially identified as an oncogene. Physiological expression of Vav1 is restricted to the hematopoietic system, where its best-known function is as a GDP/GTP nucleotide exchange factor for Rho/Rac GTPases, an activity strictly controlled by tyrosine phosphorylation. Vav1 was shown to regulate cytoskeletal rearrangement during activation of hematopoietic cells. Vav1 can also mediate other cellular functions including activation of the JNK, ERK, Ras, NF-kB, and NFAT pathways, in addition to association with numerous adapter proteins such as Shc, NCK, SLP-76, GRB2, and Crk. Although the oncogenic form of Vav1 has not been detected in clinical human tumors, its wild-type form has recently been implicated in mammalian malignancies such as neuroblastoma, melanoma, pancreatic tumors and B-cell chronic lymphocytic leukemia. This review addresses the physiological function of wild-type Vav1, its mode of activation as an oncogene, and its emerging role as a transforming protein in human cancer.
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Affiliation(s)
- Shulamit Katzav
- The Hubert H. Humphrey center for Experimental Medicine & Cancer Research, The Hebrew University-Hadassah Medical School, P.O. Box 12272, Jerusalem 91120, Israel.
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Wang S, Diao H, Guan Q, Jevnikar AM, Du C. Enhanced cardiac allograft survival by Vav1-Rac signaling blockade in a mouse model. Transpl Immunol 2007; 18:53-61. [PMID: 17584603 DOI: 10.1016/j.trim.2007.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 03/12/2007] [Accepted: 03/23/2007] [Indexed: 12/27/2022]
Abstract
BACKGROUND Vav1-Rac signaling plays a pivotal role in TCR/antigen and CD28 signals for T cell activation. However, pharmacological interference of this signaling has not been tested in the prevention of alloimmune-mediated allograft rejection. It has been demonstrated that 6-thio-GTP, a metabolite of azathioprine, specifically inhibits Vav1-Rac activity in T lymphocytes. Here we show the immunosuppressive efficacy of 6-thio-GTP in the prevention of cardiac allograft rejection. METHODS T cell proliferations were measured by (3)H-thymidine uptake. The immunosuppressive activities of 6-thio-GTP were tested in the cardiac allograft model of C57BL/6 (H-2(b)) to Balb/c (H-2(d)) mice. RESULTS 6-Thio-GTP inhibited TCR/alloantigen stimulated T cell proliferation and CD28-dependent T cell survival. Administration of 6-thio-GTP (0.5 mg/kg) prolonged graft survival to 13.8+/-2.39 days compared to 8.3+/-0.48 days in PBS controls (p<0.0001). Combination of 6-thio-GTP (0.5 mg/kg) with CsA (15 mg/kg) enhanced graft survival from 15.0+/-1.61 days in CsA treated recipients to 36.8+/-2.17 days in those received 20 days of combination therapy of CsA and 6-thio-GTP (p<0.0001), or to 42.7+/-16.63 days in the group treated with 20 days of CsA and 60 days of 6-thio-GTP (p<0.0001). Lymphocytes from 6-thio-GTP treated recipients with long-term surviving grafts (>60 days) displayed reduced proliferative response to alloantigen and higher frequencies of regulatory T cells (Treg). CONCLUSION Vav1-Rac inhibitor 6-thio-GTP prolongs allograft survival alone or in combination with CsA by suppression of alloreactive T cell activation. Our findings suggest the therapeutic potential of pharmacological interference of Vav1-Rac signaling for transplantation.
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Affiliation(s)
- Shuang Wang
- Department of Medicine, The University of Western Ontario, London, Ontario, Canada
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Di Bartolo V, Montagne B, Salek M, Jungwirth B, Carrette F, Fourtane J, Sol-Foulon N, Michel F, Schwartz O, Lehmann WD, Acuto O. A novel pathway down-modulating T cell activation involves HPK-1-dependent recruitment of 14-3-3 proteins on SLP-76. ACTA ACUST UNITED AC 2007; 204:681-91. [PMID: 17353368 PMCID: PMC2137917 DOI: 10.1084/jem.20062066] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The SH2 domain-containing leukocyte protein of 76 kD (SLP-76) is a pivotal element of the signaling machinery controlling T cell receptor (TCR)-mediated activation. Here, we identify 14-3-3epsilon and zeta proteins as SLP-76 binding partners. This interaction was induced by TCR ligation and required phosphorylation of SLP-76 at serine 376. Ribonucleic acid interference and in vitro phosphorylation experiments showed that serine 376 is the target of the hematopoietic progenitor kinase 1 (HPK-1). Interestingly, either S376A mutation or HPK-1 knockdown resulted in increased TCR-induced tyrosine phosphorylation of SLP-76 and phospholipase C-gamma1. Moreover, an SLP-76-S376A mutant induced higher interleukin 2 gene transcription than wild-type SLP-76. These data reveal a novel negative feedback loop involving HPK-1-dependent serine phosphorylation of SLP-76 and 14-3-3 protein recruitment, which tunes T cell activation.
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Affiliation(s)
- Vincenzo Di Bartolo
- Molecular Immunology Unit, Centre National de la Recherche Scientifique (CNRS) URA 1961, Institut Pasteur, 75724 Paris, Cedex 15, France.
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Dennehy KM, Elias F, Na SY, Fischer KD, Hünig T, Lühder F. Mitogenic CD28 Signals Require the Exchange Factor Vav1 to Enhance TCR Signaling at the SLP-76-Vav-Itk Signalosome. THE JOURNAL OF IMMUNOLOGY 2007; 178:1363-71. [PMID: 17237383 DOI: 10.4049/jimmunol.178.3.1363] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Almost all physiological T cell responses require costimulation-engagement of the clonotypic TCR with MHC/Ag and CD28 by its ligands CD80/86. Whether CD28 provides signals that are qualitatively unique or quantitatively amplify TCR signaling is poorly understood. In this study, we use superagonistic CD28 Abs, which induce T cell proliferation without TCR coligation, to determine how CD28 contributes to mitogenic responses. We show that mitogenic CD28 signals require but do not activate the proximal TCR components TCRzeta and Zap-70 kinase. In cell lines lacking proximal TCR signaling, an early defect in the CD28 pathway is in phosphorylation of the adaptor molecule SLP-76, which we show is essential for recruitment of the exchange factor Vav leading to Ca(2+) flux and IL-2 production. Point mutations in CD28 that result in diminished Vav phosphorylation also result in defective Ca(2+) flux, IL-2 production, and Tec-kinase phosphorylation. Using Vav1-deficient mice, we further demonstrate the importance of Vav1 for efficient proliferation, IL-2 production, and Ca(2+) flux. Our results indicate that CD28 signals feed into the TCR signaling pathway at the level of the SLP-76 signalosome.
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Affiliation(s)
- Kevin M Dennehy
- Institute of Virology and Immunobiology, University of Würzburg, Würzburg, Germany
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39
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40
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Watanabe R, Harada Y, Takeda K, Takahashi J, Ohnuki K, Ogawa S, Ohgai D, Kaibara N, Koiwai O, Tanabe K, Toma H, Sugamura K, Abe R. Grb2 and Gads exhibit different interactions with CD28 and play distinct roles in CD28-mediated costimulation. THE JOURNAL OF IMMUNOLOGY 2006; 177:1085-91. [PMID: 16818765 DOI: 10.4049/jimmunol.177.2.1085] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although both CD28 and ICOS bind PI3K and provide stimulatory signal for T cell activation, unlike CD28, ICOS does not costimulate IL-2 secretion. CD28 binds both PI3K and Grb2, whereas ICOS binds only PI3K. We have generated an ICOS mutant, which can bind Grb2 by replacement of its PI3K binding motif YMFM with the CD28 YMNM motif, and shown that it induces significant activation of the IL-2 promoter. However, this mutant ICOS was insufficient to activate the NF-kappaB pathway. In this study, we show that Gads, but not Grb2, is essential for CD28-mediated NF-kappaB activation, and its binding to CD28 requires the whole CD28 cytoplasmic domain in addition to the YMNM motif. Mutagenesis experiments have indicated that mutations in the N-terminal and/or C-terminal PXXP motif(s) of CD28 significantly reduce their association with Gads, whereas their associations with Grb2 are maintained. They induced strong activity of the NFAT/AP-1 reporter comparable with the CD28 wild type, but weak activity of the NF-kappaB reporter. Grb2- and Gads-dominant-negative mutants had a strong effect on NFAT/AP-1 reporter, but only Gads-dominant-negative significantly inhibited NF-kappaB reporter. Our data suggest that, in addition to the PI3K binding motif, the PXXP motif in the CD28 cytoplasmic domain may also define a functional difference between the CD28- and ICOS-mediated costimulatory signals by binding to Gads.
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Affiliation(s)
- Ryosuke Watanabe
- Research Institute for Biological Sciences, Faculty of Science and Technology, Tokyo University of Science, 1669 Yamazaki, Noda, Chiba 278-0022, Japan
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41
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Wood JE, Schneider H, Rudd CE. TcR and TcR-CD28 engagement of protein kinase B (PKB/AKT) and glycogen synthase kinase-3 (GSK-3) operates independently of guanine nucleotide exchange factor VAV-1. J Biol Chem 2006; 281:32385-94. [PMID: 16905544 DOI: 10.1074/jbc.m604878200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
TcRzeta/CD3 and TcRzeta/CD3-CD28 signaling requires the guanine nucleotide exchange factor (GEF) Vav-1 as well as the activation of phosphatidylinositol 3-kinase, protein kinase B (PKB/AKT), and its inactivation of glycogen synthase kinase-3 (GSK-3). Whether these two pathways are connected or operate independently of each other in T-cells has been unclear. Here, we report that anti-CD3 and anti-CD3/CD28 can induce PKB and GSK-3alpha phosphorylation in the Vav-1(-/-) Jurkat cell line J. Vav.1 and in primary CD4-positive Vav-1(-/-) T-cells. Reduced GSK-3alpha phosphorylation was observed in Vav-1,2,3(-/-) T-cells together with a complete loss of FOXO1 phosphorylation. Furthermore, PKB and GSK-3 phosphorylation was unperturbed in the presence of GEF-inactive Vav-1 that inhibited interleukin-2 gene activation and a form of Src homology 2 domain-containing lymphocytic protein of 76-kDa (SLP-76) that is defective in binding to Vav-1. The pathway also was intact under conditions of c-Jun N-terminal kinase (JNK) inhibition and disruption of the actin cytoskeleton by cytochalasin D. Both events are down-stream targets of Vav-1. Overall, our findings indicate that the TcR and TcR-CD28 driven PKB-GSK-3 pathway can operate independently of Vav-1 in T-cells.
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Affiliation(s)
- Joanne E Wood
- Molecular Immunology Section, Department of Immunology, Imperial College London, London W12 ONN, United Kingdom
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Hoff H, Burmester GR, Brunner-Weinzierl MC. Competition and cooperation: Signal transduction by CD28 and CTLA-4. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/sita.200500081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Abstract
Within the paradigm of the two-signal model of lymphocyte activation, the interest in costimulation has witnessed a remarkable emergence in the past few years with the discovery of a large array of molecules that can serve this role, including some with an inhibitory function. Interest has been further enhanced by the realization of these molecules' potential as targets to modulate clinical immune responses. Although the therapeutic translation of mechanistic knowledge in costimulatory molecules has been relatively straightforward, the capacity to target their inhibitory counterparts has remained limited. This limited capacity is particularly apparent in the case of the cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), a major negative regulator of T cell responses. Because there have been several previous comprehensive reviews on the function of this molecule, we focus here on the physiological implications of its structural features. Such an exercise may ultimately help us to design immunotherapeutic agents that target CTLA-4.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigens, CD
- Antigens, Differentiation/chemistry
- Antigens, Differentiation/genetics
- Antigens, Differentiation/metabolism
- Biological Transport, Active
- CTLA-4 Antigen
- Dimerization
- Evolution, Molecular
- Humans
- Ligands
- Lymphocyte Activation
- Models, Immunological
- Molecular Biology
- Molecular Sequence Data
- Polymorphism, Genetic
- Protein Structure, Quaternary
- Sequence Homology, Amino Acid
- Signal Transduction
- T-Lymphocytes/immunology
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Affiliation(s)
- Wendy A Teft
- The FOCIS Center for Clinical Immunology and Immunotherapeutics, Robarts Research Institute, and Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada, N6A 5K8
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Abstract
Functional polarization of leukocytes is a requisite to accomplish immune function. Immune synapse formation or chemotaxis requires asymmetric redistribution of membrane receptors, signaling molecules and the actin cytoskeleton. There is increasing evidence that compartmentalization of the plasma membrane into distinct lipid microdomains is pivotal in establishing and maintaining leukocyte polarity. Specific rafts assemble into large-scale domains to create plasma membrane asymmetries at specific cell locations, thus coordinating temporally and spatially cell signaling in these processes. In this review we discuss the roles of lipid rafts as organizers of T lymphocyte polarity during cell activation and migration.
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Affiliation(s)
- Santos Mañes
- Department of Immunology and Oncology, National Center of Biotechnology/Consejo Superior de Investigaciones Científicas, Madrid, Spain.
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Kovacs B, Parry RV, Ma Z, Fan E, Shivers DK, Freiberg BA, Thomas AK, Rutherford R, Rumbley CA, Riley JL, Finkel TH. Ligation of CD28 by its natural ligand CD86 in the absence of TCR stimulation induces lipid raft polarization in human CD4 T cells. THE JOURNAL OF IMMUNOLOGY 2006; 175:7848-54. [PMID: 16339520 DOI: 10.4049/jimmunol.175.12.7848] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Stimulation of resting CD4 T cells with anti-CD3/CD28-coated beads leads to rapid polarization of lipid rafts (LRs). It has been postulated that a major role of costimulation is to facilitate LR aggregation. CD86 is up-regulated or expressed aberrantly on immune cells in a wide array of autoimmune and infectious diseases. Using an Ig fusion with the extracellular domain of CD86 (CD86Ig) bound to a magnetic bead or K562 cells expressing CD86, we demonstrated that ligation of CD28 by its natural ligand, but not by Ab, induced polarization of LRs at the cell-bead interface of fresh human CD4 T cells in the absence of TCR ligation. This correlated with activation of Vav-1, increase of the intracellular calcium concentration, and nuclear translocation of NF-kappaB p65, but did not result in T cell proliferation or cytokine production. These studies show, for the first time, that LR polarization can occur in the absence of TCR triggering, driven solely by the CD28/CD86 interaction. This result has implications for mechanisms of T cell activation. Abnormalities in this process may alter T and B cell tolerance and susceptibility to infection.
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Affiliation(s)
- Birgit Kovacs
- Division of Rheumatology, Children's Hospital of Philadelphia, and Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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Bernard D, Riteau B, Hansen JD, Phillips RB, Michel F, Boudinot P, Benmansour A. Costimulatory Receptors in a Teleost Fish: Typical CD28, Elusive CTLA4. THE JOURNAL OF IMMUNOLOGY 2006; 176:4191-200. [PMID: 16547256 DOI: 10.4049/jimmunol.176.7.4191] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
T cell activation requires both specific recognition of the peptide-MHC complex by the TCR and additional signals delivered by costimulatory receptors. We have identified rainbow trout sequences similar to CD28 (rbtCD28) and CTLA4 (rbtCTLA4). rbtCD28 and rbtCTLA4 are composed of an extracellular Ig-superfamily V domain, a transmembrane region, and a cytoplasmic tail. The presence of a conserved ligand binding site within the V domain of both molecules suggests that these receptors likely recognize the fish homologues of the B7 family. The mRNA expression pattern of rbtCD28 and rbtCTLA4 in naive trout is reminiscent to that reported in humans and mice, because rbtCTLA4 expression within trout leukocytes was quickly up-regulated following PHA stimulation and virus infection. The cytoplasmic tail of rbtCD28 possesses a typical motif that is conserved in mammalian costimulatory receptors for signaling purposes. A chimeric receptor made of the extracellular domain of human CD28 fused to the cytoplasmic tail of rbtCD28 promoted TCR-induced IL-2 production in a human T cell line, indicating that rbtCD28 is indeed a positive costimulator. The cytoplasmic tail of rbtCTLA4 lacked obvious signaling motifs and accordingly failed to signal when fused to the huCD28 extracellular domain. Interestingly, rbtCTLA4 and rbtCD28 are not positioned on the same chromosome and thus do not belong to a unique costimulatory cluster as in mammals. Finally, our results raise questions about the origin and evolution of positive and negative costimulation in vertebrate immune systems.
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Affiliation(s)
- David Bernard
- Institut National de la Recherche Agronomique, Unité de Virologie et Immunologie Moléculaires, Jouy-en-Josas, France
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Schneider H, Valk E, da Rocha Dias S, Wei B, Rudd CE. CTLA-4 up-regulation of lymphocyte function-associated antigen 1 adhesion and clustering as an alternate basis for coreceptor function. Proc Natl Acad Sci U S A 2005; 102:12861-6. [PMID: 16126897 PMCID: PMC1192824 DOI: 10.1073/pnas.0505802102] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Although cytotoxic T lymphocyte antigen-4 (CTLA-4) negatively regulates T cell activation, the full range of functions mediated by this coreceptor has yet to be established. In this study, we report the surprising finding that CTLA-4 engagement by soluble antibody or CD80 potently up-regulates lymphocyte function-associated antigen 1 (LFA-1) adhesion to intercellular adhesion molecule-1 (ICAM-1) and receptor clustering concurrent with IL-2 inhibition. This effect was also observed with CTLA-4 ligation and not with other coreceptors. T cell antigen receptor (TcR)-induced lymphocyte function-associated antigen 1 function was also dependent on CTLA-4 expression as observed with reduced adhesion/clustering on CTLA-4(-/-) primary T cells. CTLA-4 up-regulated adhesion was mediated by regulator for cell adhesion and polarization type 1 (Rap-1) as shown by anti-CTLA-4-induced Rap-1 activation as well as Rap-1-N17 blockade and Rap-1-V12 mimicry of adhesion/clustering. Our findings identify a potent role for CTLA-4 in directing integrin adhesion and provide an alternate mechanism to account for aspects of CTLA-4 function in T cell immunity.
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Affiliation(s)
- Helga Schneider
- Molecular Immunology Section, Department of Immunology, Division of Investigative Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, London W12 ONN, United Kingdom
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Singbartl K, Bockhorn SG, Zarbock A, Schmolke M, Van Aken H. T cells modulate neutrophil-dependent acute renal failure during endotoxemia: critical role for CD28. J Am Soc Nephrol 2005; 16:720-8. [PMID: 15689402 DOI: 10.1681/asn.2004050381] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Sepsis still represents a leading cause of acute renal failure (ARF). Both lymphocytes and neutrophils (PMN) have been proposed as crucial mediators during sepsis. For further elucidation of the mechanisms of interactions between them, a murine model of LPS-induced ARF was used. In wild-type mice (WT), LPS administration led to a strong influx of PMN into the kidney (2.8-fold greater renal myeloperoxidase activity after 24 h) and to severe ARF (3.3-fold higher plasma creatinine concentrations after 24 h). By contrast, mice that were gene deficient for CD28 (CD28(-/-)), a co-stimulatory molecule for T cell activation, exhibited only minor renal dysfunction (50% protection compared with WT) and almost no PMN recruitment. When PMN(-) depleted, both WT and CD28(-/-) developed only mild ARF, similar to untreated CD28(-/-). Flow cytometry demonstrated that CD28 was vastly expressed on CD3(+) cells but not on PMN. Injecting wild-type CD3(+) cells into CD28(-/-) before LPS injection abolished the protection seen before. At baseline, both WT and CD28(-/-) displayed similar plasma concentrations of keratinocyte-derived chemokine (KC), a growth-related oncogene 1 gene product and PMN-specific chemokine. As opposed to WT, CD28(-/-) showed a greatly attenuated increase in plasma KC 4 h after LPS (2.5- versus 138.5-fold over controls, respectively). Moreover, CD28(-/-) showed less intense upregulation of renal growth-related oncogene 1 mRNA expression. Immunohistochemistry revealed considerable PMN but no T cell infiltrates in the kidney after LPS injection. In a PMN-dependent model of endotoxemic ARF, T cells, via the CD28 pathway, modulate kidney function and renal PMN recruitment. The effect on PMN is a remote one and presumably due to altered expression of PMN-specific chemokines.
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Affiliation(s)
- Kai Singbartl
- Klinik und Poliklinik für Anästhesiologie und operative Intensivmedizin, Universitätsklinikum Münster, Albert Schweitzer Strasse 33, 48129 Münster, Germany.
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Li D, Gál I, Vermes C, Alegre ML, Chong ASF, Chen L, Shao Q, Adarichev V, Xu X, Koreny T, Mikecz K, Finnegan A, Glant TT, Zhang J. Cutting Edge: Cbl-b: One of the Key Molecules Tuning CD28- and CTLA-4-Mediated T Cell Costimulation. THE JOURNAL OF IMMUNOLOGY 2004; 173:7135-9. [PMID: 15585834 DOI: 10.4049/jimmunol.173.12.7135] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Cbl-b negatively regulates CD28-dependent T cell activation. In this report, we tested the hypothesis that CD28 and CTLA-4 have opposite roles in tuning T cell activation threshold by controlling the levels of Cbl-b protein expression. We demonstrate that CD28 costimulation potentiates TCR-induced Cbl-b degradation, whereas CTLA-4-B7 interaction is required for Cbl-b re-expression. In support of this finding, Cbl-b expression in CTLA-4 knockout (KO) T cells is significantly reduced, and treating CTLA-4KO mice with human CTLA-4Ig to block CD28-B7 interaction restores Cbl-b expression on T cells. Furthermore, CD28 and CTLA-4 costimulatory effects are compromised in Cbl-bKO T cells. These observations indicate that CD28 and CTLA-4 tightly regulate Cbl-b expression which is critical for establishing the threshold for T cell activation.
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MESH Headings
- Abatacept
- Adaptor Proteins, Signal Transducing/biosynthesis
- Adaptor Proteins, Signal Transducing/deficiency
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/physiology
- Adjuvants, Immunologic/pharmacology
- Animals
- Antigens, CD
- Antigens, Differentiation/genetics
- Antigens, Differentiation/physiology
- B7-1 Antigen/metabolism
- B7-1 Antigen/pharmacology
- CD28 Antigens/genetics
- CD28 Antigens/physiology
- CTLA-4 Antigen
- Cell Proliferation
- Cells, Cultured
- Drug Synergism
- Female
- Growth Inhibitors/pharmacology
- Humans
- Immunoconjugates/pharmacology
- Lymphocyte Activation/genetics
- Lymphocyte Activation/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Proto-Oncogene Proteins c-cbl
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- Ubiquitin-Protein Ligases/biosynthesis
- Ubiquitin-Protein Ligases/deficiency
- Ubiquitin-Protein Ligases/genetics
- Ubiquitin-Protein Ligases/physiology
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Affiliation(s)
- Dongdong Li
- Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL 60612, USA
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Tavano R, Gri G, Molon B, Marinari B, Rudd CE, Tuosto L, Viola A. CD28 and lipid rafts coordinate recruitment of Lck to the immunological synapse of human T lymphocytes. THE JOURNAL OF IMMUNOLOGY 2004; 173:5392-7. [PMID: 15494485 DOI: 10.4049/jimmunol.173.9.5392] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In T lymphocytes, the Src family kinase Lck associates lipid rafts and accumulates at the immunological synapse (IS) during T cell stimulation by APCs. Using CD4- or CD28-deficient murine T cells, it was suggested that recruitment of Lck to the IS depends on CD4, whereas CD28 sustains Lck activation. However, in human resting T cells, CD28 is responsible for promoting recruitment of lipid rafts to the IS by an unknown mechanism. Thus, we performed a series of experiments to determine 1) whether Lck is recruited to the IS through lipid rafts; and 2) whether Lck recruitment to the IS of human resting T cells depends on CD4 or on CD28 engagement. We found that CD28, but not CD4, stimulation induced recruitment of Lck into detergent-resistant domains as well as its accumulation at the IS. We also found that Lck recruitment to the IS depends on the CD28 COOH-terminal PxxPP motif. Thus, the CD28-3A mutant, generated by substituting the prolines in positions 208, 211, and 212 with alanines, failed to induce Lck and lipid raft accumulation at the synapse. These results indicate that CD28 signaling orchestrates both Lck and lipid raft recruitment to the IS to amplify T cell activation.
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Affiliation(s)
- Regina Tavano
- Venetian Institute of Molecular Medicine and Department of Biomedical Science, University of Padua, Padua, Italy
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