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Rückert T, Romagnani C. Extrinsic and intrinsic drivers of natural killer cell clonality. Immunol Rev 2024; 323:80-106. [PMID: 38506411 DOI: 10.1111/imr.13324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Clonal expansion of antigen-specific lymphocytes is the fundamental mechanism enabling potent adaptive immune responses and the generation of immune memory. Accompanied by pronounced epigenetic remodeling, the massive proliferation of individual cells generates a critical mass of effectors for the control of acute infections, as well as a pool of memory cells protecting against future pathogen encounters. Classically associated with the adaptive immune system, recent work has demonstrated that innate immune memory to human cytomegalovirus (CMV) infection is stably maintained as large clonal expansions of natural killer (NK) cells, raising questions on the mechanisms for clonal selection and expansion in the absence of re-arranged antigen receptors. Here, we discuss clonal NK cell memory in the context of the mechanisms underlying clonal competition of adaptive lymphocytes and propose alternative selection mechanisms that might decide on the clonal success of their innate counterparts. We propose that the integration of external cues with cell-intrinsic sources of heterogeneity, such as variegated receptor expression, transcriptional states, and somatic variants, compose a bottleneck for clonal selection, contributing to the large size of memory NK cell clones.
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Affiliation(s)
- Timo Rückert
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Immunology, Berlin, Germany
| | - Chiara Romagnani
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Immunology, Berlin, Germany
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2
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Sadeghi Shaker M, Rokni M, Mahmoudi M, Farhadi E. Ras family signaling pathway in immunopathogenesis of inflammatory rheumatic diseases. Front Immunol 2023; 14:1151246. [PMID: 37256120 PMCID: PMC10225558 DOI: 10.3389/fimmu.2023.1151246] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 04/26/2023] [Indexed: 06/01/2023] Open
Abstract
The Ras (rat sarcoma virus) is a GTP-binding protein that is considered one of the important members of the Ras-GTPase superfamily. The Ras involves several pathways in the cell that include proliferation, migration, survival, differentiation, and fibrosis. Abnormalities in the expression level and activation of the Ras family signaling pathway and its downstream kinases such as Raf/MEK/ERK1-2 contribute to the pathogenic mechanisms of rheumatic diseases including immune system dysregulation, inflammation, and fibrosis in systemic sclerosis (SSc); destruction and inflammation of synovial tissue in rheumatoid arthritis (RA); and autoantibody production and immune complexes formation in systemic lupus erythematosus (SLE); and enhance osteoblast differentiation and ossification during skeletal formation in ankylosing spondylitis (AS). In this review, the basic biology, signaling of Ras, and abnormalities in this pathway in rheumatic diseases including SSc, RA, AS, and SLE will be discussed.
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Affiliation(s)
- Mina Sadeghi Shaker
- Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohsen Rokni
- Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Department of Immunology, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Mahdi Mahmoudi
- Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran
- Inflammation Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Elham Farhadi
- Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran
- Inflammation Research Center, Tehran University of Medical Sciences, Tehran, Iran
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3
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A Cysteine Residue within the Kinase Domain of Zap70 Regulates Lck Activity and Proximal TCR Signaling. Cells 2022; 11:cells11172723. [PMID: 36078131 PMCID: PMC9455082 DOI: 10.3390/cells11172723] [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: 07/28/2022] [Revised: 08/18/2022] [Accepted: 08/30/2022] [Indexed: 11/16/2022] Open
Abstract
Alterations in both the expression and function of the non-receptor tyrosine kinase Zap70 are associated with numerous human diseases including immunodeficiency, autoimmunity, and leukemia. Zap70 propagates the TCR signal by phosphorylating two important adaptor molecules, LAT and SLP76, which orchestrate the assembly of the signaling complex, leading to the activation of PLCγ1 and further downstream pathways. These events are crucial to drive T-cell development and T-cell activation. Recently, it has been proposed that C564, located in the kinase domain of Zap70, is palmitoylated. A non-palmitoylable C564R Zap70 mutant, which has been reported in a patient suffering from immunodeficiency, is incapable of propagating TCR signaling and activating T cells. The lack of palmitoylation was suggested as the cause of this human disease. Here, we confirm that Zap70C564R is signaling defective, but surprisingly, the defective Zap70 function does not appear to be due to a loss in palmitoylation. We engineered a C564A mutant of Zap70 which, similarly to Zap70C564R, is non-palmitoylatable. However, this mutant was capable of propagating TCR signaling. Moreover, Zap70C564A enhanced the activity of Lck and increased its proximity to the TCR. Accordingly, Zap70-deficient P116 T cells expressing Zap70C564A displayed the hyperphosphorylation of TCR-ζ and Zap70 (Y319), two well-known Lck substrates. Collectively, these data indicate that C564 is important for the regulation of Lck activity and proximal TCR signaling, but not for the palmitoylation of Zap70.
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4
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Zurli V, Montecchi T, Heilig R, Poschke I, Volkmar M, Wimmer G, Boncompagni G, Turacchio G, D'Elios MM, Campoccia G, Resta N, Offringa R, Fischer R, Acuto O, Baldari CT, Kabanova A. Phosphoproteomics of CD2 signaling reveals AMPK-dependent regulation of lytic granule polarization in cytotoxic T cells. Sci Signal 2020; 13:13/631/eaaz1965. [PMID: 32398348 DOI: 10.1126/scisignal.aaz1965] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Understanding the costimulatory signaling that enhances the activity of cytotoxic T cells (CTLs) could identify potential targets for immunotherapy. Here, we report that CD2 costimulation plays a critical role in target cell killing by freshly isolated human CD8+ T cells, which represent a challenging but valuable model to gain insight into CTL biology. We found that CD2 stimulation critically enhanced signaling by the T cell receptor in the formation of functional immune synapses by promoting the polarization of lytic granules toward the microtubule-organizing center (MTOC). To gain insight into the underlying mechanism, we explored the CD2 signaling network by phosphoproteomics, which revealed 616 CD2-regulated phosphorylation events in 373 proteins implicated in the regulation of vesicular trafficking, cytoskeletal organization, autophagy, and metabolism. Signaling by the master metabolic regulator AMP-activated protein kinase (AMPK) was a critical node in the CD2 network, which promoted granule polarization toward the MTOC in CD8+ T cells. Granule trafficking was driven by active AMPK enriched on adjacent lysosomes, revealing previously uncharacterized signaling cross-talk between vesicular compartments in CD8+ T cells. Our results thus establish CD2 signaling as key for mediating cytotoxic killing and granule polarization in freshly isolated CD8+ T cells and strengthen the rationale to choose CD2 and AMPK as therapeutic targets to enhance CTL activity.
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Affiliation(s)
- Vanessa Zurli
- Department of Life Sciences, University of Siena, via Aldo Moro 2, Siena 53100, Italy
| | - Tommaso Montecchi
- Department of Life Sciences, University of Siena, via Aldo Moro 2, Siena 53100, Italy
| | - Raphael Heilig
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Isabel Poschke
- Division of Molecular Oncology of Gastrointestinal Tumors, German Cancer Research Center, Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Michael Volkmar
- Division of Molecular Oncology of Gastrointestinal Tumors, German Cancer Research Center, Im Neuenheimer Feld 280, Heidelberg 69120, Germany
| | - Giuliana Wimmer
- Department of Life Sciences, University of Siena, via Aldo Moro 2, Siena 53100, Italy
| | - Gioia Boncompagni
- Department of Life Sciences, University of Siena, via Aldo Moro 2, Siena 53100, Italy
| | - Gabriele Turacchio
- Institute of Biochemistry and Cell Biology, National Research Council, Via Pietro Castellino 111, 80131 Naples, Italy
| | - Mario Milco D'Elios
- Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, Florence 50134, Italy
| | - Giuseppe Campoccia
- Department of Immune Hematology and Transfusion Medicine, University Hospital of Siena, viale Bracci 16, Siena 53100, Italy
| | - Nicoletta Resta
- Medical Genetics Unit, Department of Biomedical Sciences and Human Oncology, University of Bari, Policlinico Hospital, Piazza Giulio Cesare 11, Bari 70124, Italy
| | - Rienk Offringa
- Division of Molecular Oncology of Gastrointestinal Tumors, German Cancer Research Center, Im Neuenheimer Feld 280, Heidelberg 69120, Germany.,Department of Surgery, Heidelberg University Hospital, Im Neuenheimer Feld 280, Heidelberg, 69120, Germany
| | - Roman Fischer
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, UK
| | - Oreste Acuto
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | | | - Anna Kabanova
- Department of Life Sciences, University of Siena, via Aldo Moro 2, Siena 53100, Italy.
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5
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Jaiswal RK, Kumar P, Kumar M, Yadava PK. hTERT promotes tumor progression by enhancing TSPAN13 expression in osteosarcoma cells. Mol Carcinog 2018; 57:1038-1054. [PMID: 29722072 DOI: 10.1002/mc.22824] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 04/06/2018] [Accepted: 04/14/2018] [Indexed: 01/11/2023]
Abstract
Telomerase complex maintains the length of the telome, cbre, and protects erosion of the physical ends of the eukaryotic chromosome in all actively dividing cells including cancer cells. Telomerase activation extends the lifespan of cells in culture by maintaining the length of the telomere. Compared to terminally differentiated somatic cells, telomerase activity remains high in over 90% of cancer cells. It has now become clear that the role of telomerase is much more complex than just telomere lengthening. The remaining 10% of cancers deploy ALT (alternative lengthening of telomeres) pathway to maintain telomere length. Telomerase inhibitors offer a good therapeutic option. Also, telomerase-associated molecules can be targeted provided their roles are clearly established. In any case, it is necessary to understand the major role of telomerase in cancer cells. Many studies have already been done to explore gene profiling of a telomerase positive cell by knocking down expression of hTERT (telomerase reverse transcriptase). To complement these studies, we performed global gene profiling of a telomerase negative cell by ectopically expressing hTERT and studied changes in the global gene expression patterns. Analysis of microarray data for telomerase negative cells ectopically expressing telomerase showed 76 differentially regulated genes, out of which 39 genes were upregulated, and 37 were downregulated. Three upregulated genes such as TSPAN13, HMGCS2, DLX5, and three downregulated genes like DHRS2, CRYAB, and PDLIM1 were validated by real-time PCR. Knocking down of TSAPN13 in hTERT overexpressing U2OS cells enhanced the apoptosis of the cells. TSPAN13 knockdown in these cells suppressed mesenchymal properties and enhanced epithelial character.
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Affiliation(s)
- Rishi K Jaiswal
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Pramod Kumar
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.,Department of Reproductive Biology, All India Institute of Medical Sciences, New Delhi, India
| | - Manoj Kumar
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Pramod K Yadava
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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6
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Kabanova A, Zurli V, Baldari CT. Signals Controlling Lytic Granule Polarization at the Cytotoxic Immune Synapse. Front Immunol 2018. [PMID: 29515593 PMCID: PMC5826174 DOI: 10.3389/fimmu.2018.00307] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Cytotoxic immunity relies on specialized effector T cells, the cytotoxic T cells, which are endowed with specialized cytolytic machinery that permits them to induce death of their targets. Upon recognition of a target cell, cytotoxic T cells form a lytic immune synapse and by docking the microtubule-organizing center at the synaptic membrane get prepared to deliver a lethal hit of enzymes contained in lytic granules. New insights suggest that the directionality of lytic granule trafficking along the microtubules represents a fine means to tune the functional outcome of the encounter between a T cell and its target. Thus, mechanisms regulating the directionality of granule transport may have a major impact in settings characterized by evasion from the cytotoxic response, such as chronic infection and cancer. Here, we review our current knowledge on the signaling pathways implicated in the polarized trafficking at the immune synapse of cytotoxic T cells, complementing it with information on the regulation of this process in natural killer cells. Furthermore, we highlight some of the parameters which we consider critical in studying the polarized trafficking of lytic granules, including the use of freshly isolated cytotoxic T cells, and discuss some of the major open questions.
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Affiliation(s)
- Anna Kabanova
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Vanessa Zurli
- Department of Life Sciences, University of Siena, Siena, Italy
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7
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Sim GC, Wu S, Jin L, Hwu P, Radvanyi LG. Defective STAT1 activation associated with impaired IFN-γ production in NK and T lymphocytes from metastatic melanoma patients treated with IL-2. Oncotarget 2017; 7:36074-36091. [PMID: 27153543 PMCID: PMC5094984 DOI: 10.18632/oncotarget.8683] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 03/11/2016] [Indexed: 11/25/2022] Open
Abstract
High dose (HD) IL-2 therapy has been used for almost two decades as an immunotherapy for metastatic melanoma. IL-2 promotes the proliferation and effector function of T and NK cells through the tyrosine phosphorylation and activation of signal transducer and activator of transcription factors (STAT), especially STAT5. However, whether any defects in STAT activation exist in T and NK lymphocytes from melanoma patients are under debate. Here, we measured the extent of HD IL-2-induced phosphorylation of STAT5 and STAT1 in lymphocyte subsets from metastatic melanoma patients and healthy controls at a single cell level using flow cytometry. We found no defects in IL-2-induced STAT5 phosphorylation and induction of proliferation in T and NK cell subsets in vitro. This was confirmed by measuring ex vivo STAT5 activation in whole blood collected from patients during their first bolus HD IL-2 infusion. IL-2 also induced STAT1 phosphorylation via IFN-γ receptors in T and NK cell subsets through the release of IFN-γ by CD56hi and CD56lo NK cells. Further analysis revealed that melanoma patients had a sub-optimal STAT1 activation response linked to lower IL-2-induced IFN-γ secretion in both CD56hi and CD56low NK cell subsets. STAT1 activation in response to IL-2 also showed an age-related decline in melanoma patients not linked to tumor burden indicating a premature loss of NK cell function. Taken together, these findings indicate that, although STAT5 activation is normal in metastatic melanoma patients in response to IL-2, indirect STAT1 activation is defective owing to deficiencies in the NK cell response to IL-2.
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Affiliation(s)
- Geok Choo Sim
- Department of Melanoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.,Department of Immunology, Moffitt Cancer Center, Tampa, FL 22612, USA
| | - Sheng Wu
- Department of Melanoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Lei Jin
- Department of Melanoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Patrick Hwu
- Department of Melanoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Laszlo G Radvanyi
- Department of Melanoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.,Department of Immunology, Moffitt Cancer Center, Tampa, FL 22612, USA
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8
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Yang G, Chen X, Yan Z, Zhu Q, Yang C. CD11b promotes the differentiation of osteoclasts induced by RANKL through the spleen tyrosine kinase signalling pathway. J Cell Mol Med 2017; 21:3445-3452. [PMID: 28661042 PMCID: PMC5706498 DOI: 10.1111/jcmm.13254] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Accepted: 04/24/2017] [Indexed: 12/28/2022] Open
Abstract
Macrophage surface antigen‐1 (Mac‐1, CD11b/CD18) has been implicated in the regulation of osteoclastogenesis. In the synovial tissues of patients with aseptic loosening after total hip replacement, CD11b was up‐regulated, which indicated that CD11b is closely involved in osteolysis around the prosthesis. We found that CD11b, but not CD18, promoted osteoclast (OC) maturation. Here, we show CD11b up‐regulated the levels of spleen tyrosine kinase (Syk), c‐Fos and nuclear factor of activated T cells, cytoplasmic‐1 (NFATc1), as well as the activity of extracellular‐regulated kinase (Erk), and as a result, osteoclast precursors (OCPs) differentiated and became tartrate‐resistant acid phosphatase (TRAP)‐positive. In addition, increased tumour necrosis factor‐α (TNF‐α) induced by ultra‐high molecular weight polyethylene (UHMWPE) particles up‐regulated the level of CD11b. Taken together, these findings suggest that CD11b is a positive regulator of osteoclastogenesis and that it functions by activating the Syk signalling pathway, while CD18 does not have the same effect.
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Affiliation(s)
- Guoxi Yang
- Institute of Orthopaedic Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Xiaoyong Chen
- Institute of Orthopaedic Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Zhao Yan
- Institute of Orthopaedic Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Qingsheng Zhu
- Institute of Orthopaedic Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Chongfei Yang
- Institute of Orthopaedic Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
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9
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Chichelnitskiy E, Himmelseher B, Bachmann M, Pfeilschifter J, Mühl H. Hypothermia Promotes Interleukin-22 Expression and Fine-Tunes Its Biological Activity. Front Immunol 2017; 8:742. [PMID: 28706520 PMCID: PMC5489602 DOI: 10.3389/fimmu.2017.00742] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 06/12/2017] [Indexed: 01/15/2023] Open
Abstract
Disturbed homeostasis as a result of tissue stress can provoke leukocyte responses enabling recovery. Since mild hypothermia displays specific clinically relevant tissue-protective properties and interleukin (IL)-22 promotes healing at host/environment interfaces, effects of lowered ambient temperature on IL-22 were studied. We demonstrate that a 5-h exposure of endotoxemic mice to 4°C reduces body temperature by 5.0° and enhances splenic and colonic il22 gene expression. In contrast, tumor necrosis factor-α and IL-17A were not increased. In vivo data on IL-22 were corroborated using murine splenocytes and human peripheral blood mononuclear cells (PBMC) cultured upon 33°C and polyclonal T cell activation. Upregulation by mild hypothermia of largely T-cell-derived IL-22 in PBMC required monocytes and associated with enhanced nuclear T-cell nuclear factor of activated T cells (NFAT)-c2. Notably, NFAT antagonism by cyclosporin A or FK506 impaired IL-22 upregulation at normothermia and entirely prevented its enhanced expression upon hypothermic culture conditions. Data suggest that intact NFAT signaling is required for efficient IL-22 induction upon normothermic and hypothermic conditions. Hypothermia furthermore boosted early signal transducer and activator of transcription 3 activation by IL-22 and shaped downstream gene expression in epithelial-like cells. Altogether, data indicate that hypothermia supports and fine-tunes IL-22 production/action, which may contribute to regulatory properties of low ambient temperature.
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Affiliation(s)
- Evgeny Chichelnitskiy
- Pharmazentrum Frankfurt/ZAFES, University Hospital Goethe-University Frankfurt, Frankfurt, Germany
| | - Britta Himmelseher
- Pharmazentrum Frankfurt/ZAFES, University Hospital Goethe-University Frankfurt, Frankfurt, Germany
| | - Malte Bachmann
- Pharmazentrum Frankfurt/ZAFES, University Hospital Goethe-University Frankfurt, Frankfurt, Germany
| | - Josef Pfeilschifter
- Pharmazentrum Frankfurt/ZAFES, University Hospital Goethe-University Frankfurt, Frankfurt, Germany
| | - Heiko Mühl
- Pharmazentrum Frankfurt/ZAFES, University Hospital Goethe-University Frankfurt, Frankfurt, Germany
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10
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Gokhale AS, Sable R, Walker JD, McLaughlin L, Kousoulas KG, Jois SD. Inhibition of cell adhesion and immune responses in the mouse model of collagen-induced arthritis with a peptidomimetic that blocks CD2-CD58 interface interactions. Biopolymers 2016; 104:733-42. [PMID: 26031942 DOI: 10.1002/bip.22692] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 05/15/2015] [Accepted: 05/28/2015] [Indexed: 01/04/2023]
Abstract
CD2 and CD58 are two important costimulatory molecules involved in generating the signal II required for normal immune signaling. However, this interaction can be targeted to be of benefit in cases of abnormal immune signaling seen in autoimmune diseases. Our objective in this study was to design a peptidomimetic (compound 7) based on a β-strand structure of the adhesion domain of CD2 protein to inhibit CD2-CD58 protein-protein interaction and its effect on immunomodulation in the collagen-induced arthritis (CIA) model. The ability of compound 7 to bind to CD58 protein was assessed using flow cytometry. The effect of compound 7 on modulating the immune response was evaluated in an autoimmune disease using CIA in mice. The stability of compound 7 was evaluated in mouse serum using mass spectrometry. Antibody (Ab) binding inhibition studies suggested that compound 7 binds to CD58 protein. Compound 7 was successful in modulating immune responses when administered in the CIA mouse model along with reducing anti-collagen Ab levels and decreasing the level of interferon gamma (IFN-γ) relative to control treatments. Compound 7 was found to be nonimmunogenic and stable in mouse serum up to 48 h. Results suggest that compound 7 can serve as a lead compound for immunomodulation, and could be a therapeutic agent for the autoimmune disease rheumatoid arthritis (RA).
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Affiliation(s)
- Ameya S Gokhale
- Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, 71201
| | - Rushikesh Sable
- Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, 71201
| | - Jason D Walker
- Pathobiological Sciences, BioMMED, School of Veterinary Medicine, Louisiana State University Baton Rouge, 70803-8434
| | - Leslie McLaughlin
- Pathobiological Sciences, BioMMED, School of Veterinary Medicine, Louisiana State University Baton Rouge, 70803-8434
| | - Konstantin G Kousoulas
- Pathobiological Sciences, BioMMED, School of Veterinary Medicine, Louisiana State University Baton Rouge, 70803-8434
| | - Seetharama D Jois
- Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, 71201
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11
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Teshima T, Reddy P, Zeiser R. Reprint of: Acute Graft-versus-Host Disease: Novel Biological Insights. Biol Blood Marrow Transplant 2016; 22:S3-8. [PMID: 26899274 DOI: 10.1016/j.bbmt.2016.01.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/01/2015] [Indexed: 12/13/2022]
Abstract
Graft-versus-host disease (GVHD) continues to be a leading cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Recent insights into intestinal homeostasis and uncovering of new pathways and targets have greatly reconciled our understanding of GVHD pathophysiology and will reshape contemporary GVHD prophylaxis and treatment. Gastrointestinal (GI) GVHD is the major cause of mortality. Emerging data indicate that intestinal stem cells (ISCs) and their niche Paneth cells are targeted, resulting in dysregulation of the intestinal homeostasis and microbial ecology. The microbiota and their metabolites shape the immune system and intestinal homeostasis, and they may alter host susceptibility to GVHD. Protection of the ISC niche system and modification of the intestinal microbiota and metabolome to restore intestinal homeostasis may, thus, represent a novel approach to modulate GVHD and infection. Damage to the intestine plays a central role in amplifying systemic GVHD by propagating a proinflammatory cytokine milieu. Molecular targeting to inhibit kinase signaling may be a promising approach to treat GVHD, ideally via targeting the redundant effect of multiple cytokines on immune cells and enterocytes. In this review, we discuss insights on the biology of GI GVHD, interaction of microflora and metabolome with the hosts, identification of potential new target organs, and identification and targeting of novel T cell-signaling pathways. Better understanding of GVHD biology will, thus, pave a way to develop novel treatment strategies with great clinical benefits.
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Affiliation(s)
- Takanori Teshima
- Department of Hematology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
| | - Pavan Reddy
- Department of Internal Medicine, University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan
| | - Robert Zeiser
- Department of Hematology and Oncology, Freiburg University Medical Center, Albert-Ludwigs-University, Freiburg, Germany
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12
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Teshima T, Reddy P, Zeiser R. Acute Graft-versus-Host Disease: Novel Biological Insights. Biol Blood Marrow Transplant 2015; 22:11-6. [PMID: 26453971 DOI: 10.1016/j.bbmt.2015.10.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/01/2015] [Indexed: 12/22/2022]
Abstract
Graft-versus-host disease (GVHD) continues to be a leading cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Recent insights into intestinal homeostasis and uncovering of new pathways and targets have greatly reconciled our understanding of GVHD pathophysiology and will reshape contemporary GVHD prophylaxis and treatment. Gastrointestinal (GI) GVHD is the major cause of mortality. Emerging data indicate that intestinal stem cells (ISCs) and their niche Paneth cells are targeted, resulting in dysregulation of the intestinal homeostasis and microbial ecology. The microbiota and their metabolites shape the immune system and intestinal homeostasis, and they may alter host susceptibility to GVHD. Protection of the ISC niche system and modification of the intestinal microbiota and metabolome to restore intestinal homeostasis may, thus, represent a novel approach to modulate GVHD and infection. Damage to the intestine plays a central role in amplifying systemic GVHD by propagating a proinflammatory cytokine milieu. Molecular targeting to inhibit kinase signaling may be a promising approach to treat GVHD, ideally via targeting the redundant effect of multiple cytokines on immune cells and enterocytes. In this review, we discuss insights on the biology of GI GVHD, interaction of microflora and metabolome with the hosts, identification of potential new target organs, and identification and targeting of novel T cell-signaling pathways. Better understanding of GVHD biology will, thus, pave a way to develop novel treatment strategies with great clinical benefits.
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Affiliation(s)
- Takanori Teshima
- Department of Hematology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
| | - Pavan Reddy
- Department of Internal Medicine, University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan
| | - Robert Zeiser
- Department of Hematology and Oncology, Freiburg University Medical Center, Albert-Ludwigs-University, Freiburg, Germany
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13
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Kim DH, Lee YG, Park HJ, Lee JA, Kim HJ, Hwang JK, Choi JM. Piceatannol inhibits effector T cell functions by suppressing TcR signaling. Int Immunopharmacol 2015; 25:285-92. [DOI: 10.1016/j.intimp.2015.01.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 12/30/2014] [Accepted: 01/30/2015] [Indexed: 12/31/2022]
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14
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Akber U, Na BR, Ko YS, Lee HS, Kim HR, Kwon MS, Park ZY, Choi EJ, Han WC, Lee SH, Oh HM, Jun CD. Phytocomponent 4-hydroxy-3-methoxycinnamaldehyde ablates T-cell activation by targeting protein kinase C-θ and its downstream pathways. Int Immunopharmacol 2015; 25:130-40. [DOI: 10.1016/j.intimp.2015.01.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 01/17/2015] [Accepted: 01/21/2015] [Indexed: 12/18/2022]
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15
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Yoshida N, Karube K, Utsunomiya A, Tsukasaki K, Imaizumi Y, Taira N, Uike N, Umino A, Arita K, Suguro M, Tsuzuki S, Kinoshita T, Ohshima K, Seto M. Molecular characterization of chronic-type adult T-cell leukemia/lymphoma. Cancer Res 2014; 74:6129-38. [PMID: 25320005 DOI: 10.1158/0008-5472.can-14-0643] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Adult T-cell leukemia/lymphoma (ATL) is a human T-cell leukemia virus type-1-induced neoplasm with four clinical subtypes: acute, lymphoma, chronic, and smoldering. Although the chronic type is regarded as indolent ATL, about half of the cases progress to acute-type ATL. The molecular pathogenesis of acute transformation in chronic-type ATL is only partially understood. In an effort to determine the molecular pathogeneses of ATL, and especially the molecular mechanism of acute transformation, oligo-array comparative genomic hybridization and comprehensive gene expression profiling were applied to 27 and 35 cases of chronic and acute type ATL, respectively. The genomic profile of the chronic type was nearly identical to that of acute-type ATL, although more genomic alterations characteristic of acute-type ATL were observed. Among the genomic alterations frequently observed in acute-type ATL, the loss of CDKN2A, which is involved in cell-cycle deregulation, was especially characteristic of acute-type ATL compared with chronic-type ATL. Furthermore, we found that genomic alteration of CD58, which is implicated in escape from the immunosurveillance mechanism, is more frequently observed in acute-type ATL than in the chronic-type. Interestingly, the chronic-type cases with cell-cycle deregulation and disruption of immunosurveillance mechanism were associated with earlier progression to acute-type ATL. These findings suggested that cell-cycle deregulation and the immune escape mechanism play important roles in acute transformation of the chronic type and indicated that these alterations are good predictive markers for chronic-type ATL.
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Affiliation(s)
- Noriaki Yoshida
- Division of Molecular Medicine, Aichi Cancer Center Research Institute, Nagoya, Japan. Department of Cancer Genetics, Nagoya University Graduate School of Medicine at Aichi Cancer Center Research Institute, Nagoya, Japan. Department of Pathology, Kurume University School of Medicine, Kurume, Japan
| | - Kennosuke Karube
- Division of Molecular Medicine, Aichi Cancer Center Research Institute, Nagoya, Japan
| | - Atae Utsunomiya
- Department of Hematology, Imamura Bun-in Hospital, Kagoshima, Japan
| | - Kunihiro Tsukasaki
- Department of Hematology, Atomic Bomb Disease and Hibakusha Medicine Unit, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan
| | - Yoshitaka Imaizumi
- Department of Hematology, Atomic Bomb Disease and Hibakusha Medicine Unit, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan
| | - Naoya Taira
- Department of Internal Medicine, Heart Life Hospital, Nakagusukuson, Japan
| | - Naokuni Uike
- Department of Hematology, National Hospital Organization Kyushu Cancer Center, Fukuoka, Japan
| | - Akira Umino
- Division of Molecular Medicine, Aichi Cancer Center Research Institute, Nagoya, Japan. Hematology and Oncology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Kotaro Arita
- Division of Molecular Medicine, Aichi Cancer Center Research Institute, Nagoya, Japan. Third Department of Internal Medicine, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Miyuki Suguro
- Division of Molecular Medicine, Aichi Cancer Center Research Institute, Nagoya, Japan
| | - Shinobu Tsuzuki
- Division of Molecular Medicine, Aichi Cancer Center Research Institute, Nagoya, Japan
| | - Tomohiro Kinoshita
- Department of Hematology and Cell Therapy, Aichi Cancer Center, Nagoya, Japan
| | - Koichi Ohshima
- Department of Pathology, Kurume University School of Medicine, Kurume, Japan
| | - Masao Seto
- Division of Molecular Medicine, Aichi Cancer Center Research Institute, Nagoya, Japan. Department of Cancer Genetics, Nagoya University Graduate School of Medicine at Aichi Cancer Center Research Institute, Nagoya, Japan. Department of Pathology, Kurume University School of Medicine, Kurume, Japan.
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Bartelt RR, Houtman JCD. The adaptor protein LAT serves as an integration node for signaling pathways that drive T cell activation. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2012; 5:101-10. [PMID: 23150273 DOI: 10.1002/wsbm.1194] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
T cells are essential for the adaptive immune response to pathogens. However, dysfunctional T cell activity has been implicated in numerous diseases, including the failure of organ transplants, allergic reactions, asthma, autoimmune disorders, and coronary artery disease. T cell responses to pathogens require the induction of the primary activating receptor, the T cell receptor (TCR), along with other costimulatory and adhesion receptors. Signal transduction pathways activated downstream of these receptors drive T cell responses required for the immune response and disease progression. A key question in our understanding of the mechanism of T cell activation is how signaling pathways emanating from multiple receptors integrate together to alter T cell effector functions. One integration node for intracellular signaling is the membrane-associated adaptor protein linker for the activation of T cells or LAT. Upon stimulation of the TCR and other receptors, LAT is phosphorylated at several tyrosines residues on its cytoplasmic tail. This leads to the binding of SH2 domain-containing proteins and their associated molecules and the formation of large multiprotein complexes. These dynamic and highly regulated signaling complexes facilitate the production of second messengers, activate downstream pathways, induce actin cytoskeleton polymerization, and stimulate the activity of multiple transcription factors. Thus, signaling pathways from several receptors feed into LAT, which then integrates this information and selectively induces pathways critical for T cell activation and the adaptive immune response.
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17
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Spleen tyrosine kinase (Syk) is a potent target for GvHD prevention at different cellular levels. Leukemia 2012; 26:1617-29. [DOI: 10.1038/leu.2012.10] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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18
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Kim HR, Jeon BH, Lee HS, Im SH, Araki M, Araki K, Yamamura KI, Choi SC, Park DS, Jun CD. IGSF4 is a novel TCR ζ-chain-interacting protein that enhances TCR-mediated signaling. ACTA ACUST UNITED AC 2011; 208:2545-60. [PMID: 22084409 PMCID: PMC3256964 DOI: 10.1084/jem.20110853] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Immunoglobulin superfamily member 4 (IGSF4) is a known ligand of CRTAM, a receptor expressed in activated NKT and CD8(+) T cells, but its function in T cell immunity has not been elucidated. In this study, we show that IGSF4 directly interacts with the T cell receptor (TCR) ζ-chain and enhances TCR signaling by enhancing ζ-chain phosphorylation. Ectopic overexpression of IGSF4 enhances TCR-mediated T cell activation. In contrast, IGSF4 knockdown shows a dramatic decrease in markers associated with T cell activation compared with those in control small interfering RNA. The transmembrane domain is essential for TCR ζ-chain association and clustering to the immunological synapse, and the ectodomain is associated with T cell interaction with antigen-presenting cells (APCs). IGSF4-deficient mice have impaired TCR-mediated thymocyte selection and maturation. Furthermore, these mice reveal attenuated effector T cell functions accompanied by defective TCR signaling. Collectively, the results indicate that IGSF4 plays a central role in T cell functioning by dual independent mechanisms, control of TCR signaling and control of T cell-APC interaction.
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Affiliation(s)
- Hye-Ran Kim
- Immune Synapse Research Center, School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, South Korea
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19
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Hořejší V, Otáhal P, Brdička T. LAT - an important raft-associated transmembrane adaptor protein. Delivered on 6 July 2009 at the 34th FEBS Congress in Prague, Czech Republic. FEBS J 2010; 277:4383-97. [DOI: 10.1111/j.1742-4658.2010.07831.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Kim TJ, Kim N, Kim EO, Choi JR, Bluestone JA, Lee KM. Suppression of human anti-porcine natural killer cell xenogeneic responses by combinations of monoclonal antibodies specific to CD2 and NKG2D and extracellular signal-regulated kinase kinase inhibitor. Immunology 2010; 130:545-55. [PMID: 20406306 DOI: 10.1111/j.1365-2567.2010.03253.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Natural killer (NK) cells can destroy xenogeneic tissues by antibody-dependent cell cytotoxicity (ADCC) and direct lysis. Unlike ADCC, activating interactions between human NK receptors and their cognate ligands in pigs are not fully elucidated. We set up this study to identify human NK activating receptors recognizing porcine cells isolated from distinct organs, e.g., aorta, cornea and liver, and to provide a molecular basis for effective immunosuppressive regimens. Among the array of NK receptors tested, NKp46, 2B4, CD49d, CD48, CD2 and NKG2D, only CD2 and NKG2D were shown to be involved in both cytotoxicity and cytokine (interferon-gamma and tumour necrosis factor-alpha) production against porcine targets. Simultaneous blocking of CD2 and NKG2D by combining its monoclonal antibodies further suppressed xenogeneic NK responses. Moreover, addition of a suboptimal dose of PD98059, an extracellular signal-regulated kinase (ERK) kinase inhibitor, to those cells maximally reduced NK cytotoxicity, suggesting that ERK plays an important role in NK-mediated xenoreactivity. These impairments in NK cells were tightly associated with defective intracellular calcium mobilization and the subsequent degranulation process. Therefore, our data demonstrate a distinct role of CD2 and NKG2D on human NK cells in recognizing porcine grafts and further provide a potentially efficacious combinational regimen using anti-CD2 and anti-NKG2D monoclonal antibodies with PD98059 in a pig-to-human transplantation model.
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Affiliation(s)
- Tae-Jin Kim
- Global Research Lab, Department of Biochemistry and Division of Brain Korea 21 Program for Biomedical Science, Korea University College of Medicine, Seoul, Korea
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21
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Abstract
SummaryThe MAP kinases (MAPKs), including ERK, JNK and p38 families comprise part of the intracellular signalling network, which is essential for signal transduction from receptors and stimuli to the biological reaction. Activity of MAPKs plays a crucial role in normal functioning of the immune system. By taking part in cytokine production upon signalling from activated TLR receptors, MAPKs are involved in initiation of innate immunity and in responses to binding of cytokines by appropriate receptors. MAPKs activity is also important for T and B lymphocyte differentiation, by the ITAM signalling pathway. Moreover, their involvement in apoptosis supports lymphocyte T cytotoxicity and enables the removal of damaged, infected or transformed cells. Correct functioning of the MAPK signalling is crucial for effective immune response, and therefore MAPKs’ inhibitors constitute a promising therapeutic goal
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22
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Ghosh D, Tsokos GC. Spleen tyrosine kinase: an Src family of non-receptor kinase has multiple functions and represents a valuable therapeutic target in the treatment of autoimmune and inflammatory diseases. Autoimmunity 2010; 43:48-55. [PMID: 20001666 DOI: 10.3109/08916930903374717] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Spleen tyrosine kinase (Syk) is involved in the development and function of B and T cells, the Fc receptor-mediated degranulation of basophils and mast cells. Recent work has assigned important roles for Syk in the aberrant function of T cells in patients with systemic lupus erythematosus (SLE), osteoclasts, and urate crystal-induced neutrophil stimulation. Preclinical and early clinical studies have urged Syk inhibition for the treatment of patients with rheumatoid arthritis, whereas ex vivo experiments and preclinical studies point to a therapeutic potential of Syk inhibition in patients with SLE and crystal-induced arthritides.
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Affiliation(s)
- Debjani Ghosh
- Division of Rheumatology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA
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23
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Nguyen V, Cao L, Lin JT, Hung N, Ritz A, Yu K, Jianu R, Ulin SP, Raphael BJ, Laidlaw DH, Brossay L, Salomon AR. A new approach for quantitative phosphoproteomic dissection of signaling pathways applied to T cell receptor activation. Mol Cell Proteomics 2009; 8:2418-31. [PMID: 19605366 DOI: 10.1074/mcp.m800307-mcp200] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Reversible protein phosphorylation plays a pivotal role in the regulation of cellular signaling pathways. Current approaches in phosphoproteomics focus on analysis of the global phosphoproteome in a single cellular state or of receptor stimulation time course experiments, often with a restricted number of time points. Although these studies have provided some insights into newly discovered phosphorylation sites that may be involved in pathways, they alone do not provide enough information to make precise predictions of the placement of individual phosphorylation events within a signaling pathway. Protein disruption and site-directed mutagenesis are essential to clearly define the precise biological roles of the hundreds of newly discovered phosphorylation sites uncovered in modern proteomics experiments. We have combined genetic analysis with quantitative proteomic methods and recently developed visual analysis tools to dissect the tyrosine phosphoproteome of isogenic Zap-70 tyrosine kinase null and reconstituted Jurkat T cells. In our approach, label-free quantitation using normalization to copurified phosphopeptide standards is applied to assemble high density temporal data within a single cell type, either Zap-70 null or reconstituted cells, providing a list of candidate phosphorylation sites that change in abundance after T cell stimulation. Stable isotopic labeling of amino acids in cell culture (SILAC) ratios are then used to compare Zap-70 null and reconstituted cells across a time course of receptor stimulation, providing direct information about the placement of newly observed phosphorylation sites relative to Zap-70. These methods are adaptable to any cell culture signaling system in which isogenic wild type and mutant cells have been or can be derived using any available phosphopeptide enrichment strategy.
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Affiliation(s)
- Vinh Nguyen
- Department of Molecular Biology, Brown University, Providence, Rhode Island 02912, USA
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24
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Gibbings D, Befus AD. CD4 and CD8: an inside-out coreceptor model for innate immune cells. J Leukoc Biol 2009; 86:251-9. [PMID: 19401396 DOI: 10.1189/jlb.0109040] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
CD8 and CD4 are expressed by several cell types that do not express TCR. These include DCs, macrophages, monocytes, and NK cells. CD8(+) monocytes and macrophages are abundant at the site of pathology in many rat disease models, particularly those involving immune complex-mediated pathology. Indeed, in some disease models, CD8(+) macrophages correlate with severity of pathology or directly cause pathology or tumor cell killing. Evidence suggests CD8 or CD4 can enhance FcgammaR-dependent responses of human monocytes. Building on data that key components of TCR and FcgammaR signaling can substitute one another efficiently, we postulate that CD4 and CD8 operate with FcgammaR and potentially other receptors to enhance responses of T cells and various innate immune cells. Our model suggests CD8 on myeloid cells may contribute directly to tumor killing and tissue pathology by enhancing FcgammaR responses. Moreover, the model suggests a role for CD8 in cross-presentation of antibody-associated antigen by DCs and a new mechanism to regulate TCR sensitivity.
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Affiliation(s)
- Derrick Gibbings
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
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25
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Kaizuka Y, Douglass AD, Vardhana S, Dustin ML, Vale RD. The coreceptor CD2 uses plasma membrane microdomains to transduce signals in T cells. ACTA ACUST UNITED AC 2009; 185:521-34. [PMID: 19398758 PMCID: PMC2700390 DOI: 10.1083/jcb.200809136] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The interaction between a T cell and an antigen-presenting cell (APC) can trigger a signaling response that leads to T cell activation. Prior studies have shown that ligation of the T cell receptor (TCR) triggers a signaling cascade that proceeds through the coalescence of TCR and various signaling molecules (e.g., the kinase Lck and adaptor protein LAT [linker for T cell activation]) into microdomains on the plasma membrane. In this study, we investigated another ligand-receptor interaction (CD58-CD2) that facilities T cell activation using a model system consisting of Jurkat T cells interacting with a planar lipid bilayer that mimics an APC. We show that the binding of CD58 to CD2, in the absence of TCR activation, also induces signaling through the actin-dependent coalescence of signaling molecules (including TCR-zeta chain, Lck, and LAT) into microdomains. When simultaneously activated, TCR and CD2 initially colocalize in small microdomains but then partition into separate zones; this spatial segregation may enable the two receptors to enhance signaling synergistically. Our results show that two structurally distinct receptors both induce a rapid spatial reorganization of molecules in the plasma membrane, suggesting a model for how local increases in the concentration of signaling molecules can trigger T cell signaling.
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Affiliation(s)
- Yoshihisa Kaizuka
- Department of Cellular and Molecular Pharmacology, The Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143, USA
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26
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Shim JH, Choi HS, Pugliese A, Lee SY, Chae JI, Choi BY, Bode AM, Dong Z. (-)-Epigallocatechin gallate regulates CD3-mediated T cell receptor signaling in leukemia through the inhibition of ZAP-70 kinase. J Biol Chem 2008; 283:28370-9. [PMID: 18687687 DOI: 10.1074/jbc.m802200200] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The zeta chain-associated 70-kDa protein (ZAP-70) of tyrosine kinase plays a critical role in T cell receptor-mediated signal transduction and the immune response. A high level of ZAP-70 expression is observed in leukemia, which suggests ZAP-70 as a logical target for immunomodulatory therapies. (-)-Epigallocatechin gallate (EGCG) is one of the major green tea catechins that is suggested to have a role as a preventive agent in cancer, obesity, diabetes, and cardiovascular disease. Here we identified ZAP-70 as an important and novel molecular target of EGCG in leukemia cells. ZAP-70 and EGCG displayed high binding affinity (Kd = 0.6207 micromol/liter), and additional results revealed that EGCG effectively suppressed ZAP-70, linker for the activation of T cells, phospholipase Cgamma1, extracellular signaling-regulated kinase, and MAPK kinase activities in CD3-activated T cell leukemia. Furthermore, the activation of activator protein-1 and interleukin-2 induced by CD3 was dose-dependently inhibited by EGCG treatment. Notably, EGCG dose-dependently induced caspase-mediated apoptosis in P116.cl39 ZAP-70-expressing leukemia cells, whereas P116 ZAP-70-deficient cells were resistant to EGCG treatment. Molecular docking studies, supported by site-directed mutagenesis experiments, showed that EGCG could form a series of intermolecular hydrogen bonds and hydrophobic interactions within the ATP binding domain, which may contribute to the stability of the ZAP-70-EGCG complex. Overall, these results strongly indicated that ZAP-70 activity was inhibited specifically by EGCG, which contributed to suppressing the CD3-mediated T cell-induced pathways in leukemia cells.
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Affiliation(s)
- Jung-Hyun Shim
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
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27
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Rodriguez-Manzanet R, Meyers JH, Balasubramanian S, Slavik J, Kassam N, Dardalhon V, Greenfield EA, Anderson AC, Sobel RA, Hafler DA, Strom TB, Kuchroo VK. TIM-4 expressed on APCs induces T cell expansion and survival. THE JOURNAL OF IMMUNOLOGY 2008; 180:4706-13. [PMID: 18354194 DOI: 10.4049/jimmunol.180.7.4706] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
TIM (T cell, Ig, mucin) proteins can regulate T cell immune responses. Tim-4 mRNA is not expressed in T cells, but exclusively in APCs. Tim-4 is a ligand for Tim-1 and Tim-4.Ig fusion protein was shown to either inhibit or expand T cells. However, the molecular basis for such opposite effects was not defined. By generating mAbs, we show that expression of Tim-4 protein is restricted to CD11c(+) and CD11b(+) cells and is up-regulated upon activation. We show that Tim-4 specifically phosphorylates Tim-1 and induces T cell expansion by enhancing cell division and reducing apoptosis. Tim-4 also induces the phosphorylation of signaling molecules LAT, Akt, and ERK1/2 in T cells. Tim-4, expressed on APCs, is a costimulatory molecule that promotes T cell expansion and survival by cross-linking Tim-1 on T cells.
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Affiliation(s)
- Roselynn Rodriguez-Manzanet
- Department of Neurology, Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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28
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Bueno C, Lemke CD, Criado G, Baroja ML, Ferguson SSG, Rahman AKMNU, Tsoukas CD, McCormick JK, Madrenas J. Bacterial Superantigens Bypass Lck-Dependent T Cell Receptor Signaling by Activating a Gα11-Dependent, PLC-β-Mediated Pathway. Immunity 2006; 25:67-78. [PMID: 16860758 DOI: 10.1016/j.immuni.2006.04.012] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 04/07/2006] [Accepted: 04/12/2006] [Indexed: 11/18/2022]
Abstract
The paradigm to explain antigen-dependent T cell receptor (TCR) signaling is based on the activation of the CD4 or CD8 coreceptor-associated kinase Lck. It is widely assumed that this paradigm is also applicable to signaling by bacterial superantigens. However, these bacterial toxins can activate human T cells lacking Lck, suggesting the existence of an additional pathway of TCR signaling. Here we showed that this alternative pathway operates in the absence of Lck-dependent tyrosine-phosphorylation events and was initiated by the TCR-dependent activation of raft-enriched heterotrimeric Galpha11 proteins. This event, in turn, activated a phospholipase C-beta and protein kinase C-mediated cascade that turned on the mitogen-activated protein kinases ERK-1 and ERK-2, triggered Ca(2+) influx, and translocated the transcription factors NF-AT and NF-kappaB to the nucleus, ultimately inducing the production of interleukin-2 in Lck-deficient T cells. The triggering of this alternative pathway by superantigens suggests that these toxins use a G protein-coupled receptor as a coreceptor on T cells.
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Affiliation(s)
- Clara Bueno
- The FOCIS Centre for Clinical Immunology and Immunotherapeutics, London, Ontario N6A 5K8, Canada
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29
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Koretzky GA, Abtahian F, Silverman MA. SLP76 and SLP65: complex regulation of signalling in lymphocytes and beyond. Nat Rev Immunol 2006; 6:67-78. [PMID: 16493428 DOI: 10.1038/nri1750] [Citation(s) in RCA: 205] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
SLP76 and SLP65 are adaptor proteins that lack intrinsic enzymatic activity but contain multiple protein-binding domains. These proteins are essential for signalling downstream of integrins and receptors that contain immunoreceptor tyrosine-based activation motifs. The absence of these adaptor proteins profoundly affects various lineages in the haematopoietic compartment and severely compromises vascular development, highlighting their importance as regulators of signalling cascades. In this Review, we discuss the role of SLP76 and SLP65 in several signalling pathways in haematopoietic cells, with an emphasis on recent studies that provide insight into their mechanisms of action.
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Affiliation(s)
- Gary A Koretzky
- Department of Pathology and Laboratory Medicine, Abramson Family Cancer Research Institute, University of Pennsylvania, 415 BRBII/III, 421 Curie Boulevard, Philadelphia, Pennsylvania 19104, USA.
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30
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McNerney ME, Kumar V. The CD2 family of natural killer cell receptors. Curr Top Microbiol Immunol 2006; 298:91-120. [PMID: 16323413 DOI: 10.1007/3-540-27743-9_5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The CD2 family of receptors is evolutionarily conserved and widely expressed on cells within the hematopoietic compartment. In recent years several new members have been identified with important roles in the immune system. CD2 family members regulate natural killer (NK) cell lytic activity and inflammatory cytokine production when engaged by ligands on tumor cells. Furthermore, a subfamily of CD2 receptors, the CD 150-like molecules, has been implicated in the pathogenesis of X-linked lymphoproliferative disease (XLP). Many of these receptors have now been shown to bind homophilically or heterophilically to other molecules within the family. With these discoveries a novel mechanism for lymphocyte regulation has emerged: CD2 family members on NK cells engage ligands on neighboring NK cells, leading to NK cell stimulation. Moreover, heterotypic stimulatory interactions between NK cells and other leukocytes also occur. In this manner, CD2 family members may provide interlymphocyte communication that maintains organization within the hematopoietic compartment and amplifies immune responses. This review discusses these multiple roles for CD2 family members, focusing specifically on the regulation of NK cells.
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Affiliation(s)
- M E McNerney
- Department of Pathology, Committee on Immunology, University of Chicago, 5841 S. Maryland Ave., S-315 MC3083, Chicago, IL 60637, USA
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31
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Huynh NT, Ffrench RA, Boadle RA, Manolios N. Transmembrane T-cell receptor peptides inhibit B- and natural killer-cell function. Immunology 2003; 108:458-64. [PMID: 12667207 PMCID: PMC1782915 DOI: 10.1046/j.1365-2567.2003.01614.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A synthetic hydrophobic peptide (core peptide; CP) containing two positively charged amino acids, lysine and arginine was derived from the transmembrane sequence of the T-cell receptor (TCR) alpha chain and has been shown to inhibit T-cell-mediated inflammation. In this study, we investigated the specificity of CP (10 microm) on lymphocyte function and found that it significantly inhibited interleukin-2 production in T cells and natural killer cytotoxicity by 46-58% compared to positive control. CP had no effects on B-cell proliferative responses when used at these concentrations; however, it suppressed B-cell proliferation at higher concentrations (50 microm). Inhibition by CP was not the result of membrane pore formation or cytotoxicity when examined by trypan blue, propidium iodide staining or transmission electron microscopy. CP analogues, with both lysine and arginine replaced by neutral or negatively charged amino acids, or by randomly distributing charges in the peptide sequence, had no effect on lymphocyte function. These results suggest that peptide inhibition is affected by its structure and charge interactions, and may involve common signalling molecules in T, B and natural killer cells. The potential of the immuno-inhibitory effects of CP as a novel anti-inflammatory peptide in therapy should be further explored.
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Affiliation(s)
- Nghi T Huynh
- Department of Rheumatology, Westmead HospitalSydney, NSW, Australia
| | - Rosemary A Ffrench
- Paediatric Research Laboratories, Sydney Children's HospitalSydney, NSW, Australia
| | - Ross A Boadle
- Electron Microscopy Unit, Westmead Millennium Institute and Institute for Clinical Pathology and Medical Research, Westmead HospitalSydney, NSW, Australia
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32
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Vyas YM, Maniar H, Dupont B. Visualization of signaling pathways and cortical cytoskeleton in cytolytic and noncytolytic natural killer cell immune synapses. Immunol Rev 2002; 189:161-78. [PMID: 12445273 DOI: 10.1034/j.1600-065x.2002.18914.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Recent applications of imaging approaches and other methods of cell biology have provided high-resolution visualization of the location of fluorescent proteins in living and fixed cells during cell-cell interactions between lymphocytes, antigen presenting cells and target cells. We review the composition and dynamics of molecular and cytoskeletal events occurring during natural killer cell interactions with susceptible and nonsusceptible target cells. The natural killer cell immune synapse and the concomitant changes in cytoskeletal components and cytoplasmic organelles are described. The findings are compared with the observations made in T helper cells and cytotoxic T cells. It is concluded that the cytolytic immune synapses display spatial-temporal dynamics that are accelerated as compared with T helper cells. In addition, the cytolytic conjugates have unique characteristics relating to their effector function. Furthermore, the natural killer cell immune synapses in cytolytic and noncytolytic interactions are distinctly different and display patterns consistent with characteristic signaling pathways identified in biochemical studies of disrupted cells. The precise relationship between different stages of the natural killer cell immune synapse formation and progression in signal transduction pathways is yet to be established.
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Affiliation(s)
- Yatin M Vyas
- Immunology Program, Sloan-Kettering Institute for Cancer Research, New York, NY 10021, USA
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Teixeiro E, Fuentes P, Galocha B, Alarcon B, Bragado R. T cell receptor-mediated signal transduction controlled by the beta chain transmembrane domain: apoptosis-deficient cells display unbalanced mitogen-activated protein kinases activities upon T cell receptor engagement. J Biol Chem 2002; 277:3993-4002. [PMID: 11724779 DOI: 10.1074/jbc.m107797200] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The bases that support the versatility of the T cell receptor (TCR) to generate distinct T cell responses remain unclear. We have previously shown that mutant cells in the transmembrane domain of TCRbeta chain are impaired in TCR-induced apoptosis but are not affected in other functions. Here we describe the biochemical mechanisms by which this mutant receptor supports some T cell responses but fails to induce apoptosis. Extracellular signal-regulated protein kinase (ERK) is activated at higher and more sustained levels in TCRbeta-mutated than in wild type cells. Conversely, activation of both c-Jun N-terminal kinase and p38 mitogen-activated protein kinase is severely reduced in mutant cells. By attempting to link this unbalanced induction to altered upstream events, we found that ZAP-70 is normally activated. However, although SLP-76 phosphorylation is normally induced, TCR engagement of mutant cells results in lower tyrosine phosphorylation of LAT but in higher tyrosine phosphorylation of Vav than in wild type cells. The results suggest that an altered signaling cascade leading to an imbalance in mitogen-activated protein kinase activities is involved in the selective impairment of apoptosis in these mutant cells. Furthermore, they also provide new insights in the contribution of TCR to decipher the signals that mediate apoptosis distinctly from proliferation.
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MESH Headings
- Antigens, CD/metabolism
- Antigens, Differentiation, T-Lymphocyte/metabolism
- Apoptosis
- Humans
- Jurkat Cells
- Lectins, C-Type
- Mitogen-Activated Protein Kinases/metabolism
- Mutation
- Phosphorylation
- Precipitin Tests
- Protein Kinase C/metabolism
- Protein Transport
- Protein-Tyrosine Kinases/metabolism
- Receptors, Antigen, T-Cell/chemistry
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/physiology
- Signal Transduction/physiology
- Tyrosine/metabolism
- ZAP-70 Protein-Tyrosine Kinase
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Affiliation(s)
- Emma Teixeiro
- Department of Immunology, Fundación Jiménez Diaz, Avenida. Reyes Católicos 2, 28040 Madrid, Spain
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Zaffran Y, Destaing O, Roux A, Ory S, Nheu T, Jurdic P, Rabourdin-Combe C, Astier AL. CD46/CD3 costimulation induces morphological changes of human T cells and activation of Vav, Rac, and extracellular signal-regulated kinase mitogen-activated protein kinase. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:6780-5. [PMID: 11739493 DOI: 10.4049/jimmunol.167.12.6780] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Efficient T cell activation requires at least two signals, one mediated by the engagement of the TCR-CD3 complex and another one mediated by a costimulatory molecule. We recently showed that CD46, a complement regulatory receptor for C3b as well as a receptor for several pathogens, could act as a potent costimulatory molecule for human T cells, highly promoting T cell proliferation. Indeed, we show in this study that CD46/CD3 costimulation induces a synergistic activation of extracellular signal-related kinase mitogen-activated protein kinase. Furthermore, whereas T lymphocytes primarily circulate within the bloodstream, activation may induce their migration toward secondary lymphoid organs or other tissues to encounter APCs or target cells. In this study, we show that CD46/CD3 costimulation also induces drastic morphological changes of primary human T cells, as well as actin relocalization. Moreover, we show that the GTP/GDP exchange factor Vav is phosphorylated upon CD46 stimulation alone, and that CD46/CD3 costimulation induces a synergistic increase of Vav phosphorylation. These results prompted us to investigate whether CD46/CD3 costimulation induced the activation of GTPases from the Rho family. Indeed, we report that the small GTPase Rac is also activated upon CD46/CD3 costimulation, whereas no change of Rho and Cdc42 activity could be detected. Therefore, CD46 costimulation profoundly affects T cell behavior, and these results provide important data concerning the biology of primary human T cells.
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Affiliation(s)
- Y Zaffran
- Institut National de la Santé et de la Recherche Médicale Unité 503, Centre Européen de Recherche en Virologie et Immunologie, Lyon, France
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Martelli MP, Boomer J, Bu M, Bierer BE. T cell regulation of p62(dok) (Dok1) association with Crk-L. J Biol Chem 2001; 276:45654-61. [PMID: 11553620 DOI: 10.1074/jbc.m105777200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
In addition to engagement of the T cell receptor-CD3 complex, T lymphocytes can be activated by a variety of cell surface molecules including the approximately 50-kDa surface receptor CD2. While the majority of biochemical signaling elements are triggered by either CD2 or TcR-CD3 receptors, a small number of proteins are engaged by only one receptor. Recently, p62(dok) (Dok1), a member of the Dok family of adapter molecules, has been reported to be activated by CD2 and not by CD3 engagement. Here we have examined the role of p62(dok) in CD2-dependent signaling in Jurkat T cells. As previously reported, we find that ligation of the CD2 molecule by mitogenic pairs of anti-CD2 mAbs led to phosphorylation of p62(dok). While CD2-induced p62(dok) tyrosine phosphorylation was independent of both the p36/38 membrane adapter protein linker of activated T cells (LAT) and the ZAP70/Syk family of kinases, it was dependent upon the Src family of kinases including Lck and Fyn. We find further that CD2 engagement induced the association of tyrosine-phosphorylated p62(dok) to Crk-L. The CD2-dependent association of p62(dok) to Crk-L was independent of expression of the ZAP70/Syk family of kinases. Of note, while T cell receptor-CD3 engagement did not induce either p62(dok) phosphorylation or Crk-L association in Jurkat T cells, it did inhibit CD2-dependent p62(dok)-Crk-L complexes; this TcR-CD3-mediated regulation was dependent upon ZAP70 kinase activity. Our data suggest that phosphorylation of p62(dok) and its interaction with other signaling proteins may depend upon integrated signals emanating from the CD2 receptor, utilizing a ZAP70/LAT-independent pathway, and the TcR-CD3 receptor, which is ZAP70/Syk-dependent.
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Affiliation(s)
- M P Martelli
- Laboratory of Lymphocyte Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892, USA
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Wilson BS, Pfeiffer JR, Surviladze Z, Gaudet EA, Oliver JM. High resolution mapping of mast cell membranes reveals primary and secondary domains of Fc(epsilon)RI and LAT. J Cell Biol 2001; 154:645-58. [PMID: 11489921 PMCID: PMC2196429 DOI: 10.1083/jcb.200104049] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In mast cells, cross-linking the high-affinity IgE receptor (Fc(epsilon)RI) initiates the Lyn-mediated phosphorylation of receptor ITAMs, forming phospho-ITAM binding sites for Syk. Previous immunogold labeling of membrane sheets showed that resting Fc(epsilon)RI colocalize loosely with Lyn, whereas cross-linked Fc(epsilon)RI redistribute into specialized domains (osmiophilic patches) that exclude Lyn, accumulate Syk, and are often bordered by coated pits. Here, the distribution of Fc(epsilon)RI beta is mapped relative to linker for activation of T cells (LAT), Grb2-binding protein 2 (Gab2), two PLCgamma isoforms, and the p85 subunit of phosphatidylinositol 3-kinase (PI3-kinase), all implicated in the remodeling of membrane inositol phospholipids. Before activation, PLCgamma1 and Gab2 are not strongly membrane associated, LAT occurs in small membrane clusters separate from receptor, and PLCgamma2, that coprecipitates with LAT, occurs in clusters and along cytoskeletal cables. After activation, PLCgamma2, Gab2, and a portion of p85 colocalize with Fc(epsilon)RI beta in osmiophilic patches. LAT clusters enlarge within 30 s of receptor activation, forming elongated complexes that can intersect osmiophilic patches without mixing. PLCgamma1 and another portion of p85 associate preferentially with activated LAT. Supporting multiple distributions of PI3-kinase, Fc(epsilon)RI cross-linking increases PI3-kinase activity in anti-LAT, anti-Fc(epsilon)RIbeta, and anti-Gab2 immune complexes. We propose that activated mast cells propagate signals from primary domains organized around Fc(epsilon)RIbeta and from secondary domains, including one organized around LAT.
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Affiliation(s)
- B S Wilson
- Department of Pathology and Cancer Research and Treatment Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
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