1
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Ouyang M, Xing Y, Zhang S, Li L, Pan Y, Deng L. Development of FRET Biosensor to Characterize CSK Subcellular Regulation. BIOSENSORS 2024; 14:206. [PMID: 38667199 PMCID: PMC11048185 DOI: 10.3390/bios14040206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/13/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024]
Abstract
C-terminal Src kinase (CSK) is the major inhibitory kinase for Src family kinases (SFKs) through the phosphorylation of their C-tail tyrosine sites, and it regulates various types of cellular activity in association with SFK function. As a cytoplasmic protein, CSK needs be recruited to the plasma membrane to regulate SFKs' activity. The regulatory mechanism behind CSK activity and its subcellular localization remains largely unclear. In this work, we developed a genetically encoded biosensor based on fluorescence resonance energy transfer (FRET) to visualize the CSK activity in live cells. The biosensor, with an optimized substrate peptide, confirmed the crucial Arg107 site in the CSK SH2 domain and displayed sensitivity and specificity to CSK activity, while showing minor responses to co-transfected Src and Fyn. FRET measurements showed that CSK had a relatively mild level of kinase activity in comparison to Src and Fyn in rat airway smooth muscle cells. The biosensor tagged with different submembrane-targeting signals detected CSK activity at both non-lipid raft and lipid raft microregions, while it showed a higher FRET level at non-lipid ones. Co-transfected receptor-type protein tyrosine phosphatase alpha (PTPα) had an inhibitory effect on the CSK FRET response. The biosensor did not detect obvious changes in CSK activity between metastatic cancer cells and normal ones. In conclusion, a novel FRET biosensor was generated to monitor CSK activity and demonstrated CSK activity existing in both non-lipid and lipid raft membrane microregions, being more present at non-lipid ones.
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Affiliation(s)
- Mingxing Ouyang
- Institute of Biomedical Engineering and Health Sciences, School of Medical and Health Engineering, Changzhou University, Changzhou 213164, China; (Y.X.); (S.Z.); (L.L.); (Y.P.)
| | - Yujie Xing
- Institute of Biomedical Engineering and Health Sciences, School of Medical and Health Engineering, Changzhou University, Changzhou 213164, China; (Y.X.); (S.Z.); (L.L.); (Y.P.)
- School of Pharmacy, Changzhou University, Changzhou 213164, China
| | - Shumin Zhang
- Institute of Biomedical Engineering and Health Sciences, School of Medical and Health Engineering, Changzhou University, Changzhou 213164, China; (Y.X.); (S.Z.); (L.L.); (Y.P.)
| | - Liting Li
- Institute of Biomedical Engineering and Health Sciences, School of Medical and Health Engineering, Changzhou University, Changzhou 213164, China; (Y.X.); (S.Z.); (L.L.); (Y.P.)
- School of Pharmacy, Changzhou University, Changzhou 213164, China
| | - Yan Pan
- Institute of Biomedical Engineering and Health Sciences, School of Medical and Health Engineering, Changzhou University, Changzhou 213164, China; (Y.X.); (S.Z.); (L.L.); (Y.P.)
| | - Linhong Deng
- Institute of Biomedical Engineering and Health Sciences, School of Medical and Health Engineering, Changzhou University, Changzhou 213164, China; (Y.X.); (S.Z.); (L.L.); (Y.P.)
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2
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Martin-Salgado M, Ochoa-Echeverría A, Mérida I. Diacylglycerol kinases: A look into the future of immunotherapy. Adv Biol Regul 2024; 91:100999. [PMID: 37949728 DOI: 10.1016/j.jbior.2023.100999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 11/01/2023] [Indexed: 11/12/2023]
Abstract
Cancer still represents the second leading cause of death right after cardiovascular diseases. According to the World Health Organization (WHO), cancer provoked around 10 million deaths in 2020, with lung and colon tumors accounting for the deadliest forms of cancer. As tumor cells become resistant to traditional therapeutic approaches, immunotherapy has emerged as a novel strategy for tumor control. T lymphocytes are key players in immune responses against tumors. Immunosurveillance allows identification, targeting and later killing of cancerous cells. Nevertheless, tumors evolve through different strategies to evade the immune response and spread in a process called metastasis. The ineffectiveness of traditional strategies to control tumor growth and expansion has led to novel approaches considering modulation of T cell activation and effector functions. Program death receptor 1 (PD-1) and cytotoxic T-lymphocyte antigen 4 (CTLA-4) showed promising results in the early 90s and nowadays are still being exploited together with other drugs for several cancer types. Other negative regulators of T cell activation are diacylglycerol kinases (DGKs) a family of enzymes that catalyze the conversion of diacylglycerol (DAG) into phosphatidic acid (PA). In T cells, DGKα and DGKζ limit the PLCγ/Ras/ERK axis thus attenuating DAG mediated signaling and T cell effector functions. Upregulation of either of both isoforms results in impaired Ras activation and anergy induction, whereas germline knockdown mice showed enhanced antitumor properties and more effective immune responses against pathogens. Here we review the mechanisms used by DGKs to ameliorate T cell activation and how inhibition could be used to reinvigorate T cell functions in cancer context. A better knowledge of the molecular mechanisms involved upon T cell activation will help to improve current therapies with DAG promoting agents.
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Affiliation(s)
- Miguel Martin-Salgado
- Department of Immunology and Oncology. National Centre for Biotechnology. Spanish Research Council (CNB-CSIC), Spain
| | - Ane Ochoa-Echeverría
- Department of Immunology and Oncology. National Centre for Biotechnology. Spanish Research Council (CNB-CSIC), Spain
| | - Isabel Mérida
- Department of Immunology and Oncology. National Centre for Biotechnology. Spanish Research Council (CNB-CSIC), Spain.
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3
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Petersen SH, Al Badawy K, Hopkins R, Vu DL, Rahmani M, Maia SM, Connolly JE. A novel GPI-anchored dominant-negative TGF-β receptor II renders T cells unresponsive to TGF-β signaling. Mol Ther Oncolytics 2023; 31:100730. [PMID: 37829123 PMCID: PMC10565558 DOI: 10.1016/j.omto.2023.100730] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 09/21/2023] [Indexed: 10/14/2023] Open
Abstract
Transforming growth factor β (TGF-β) is a pleiotropic cytokine expressed by a wide range of cell types and is known for hampering the effectiveness of cancer immune cell therapeutic approaches. We have designed a novel construct containing the extracellular domain of the TGF-β receptor II linked to a glycosylphosphatidylinositol (GPI) anchor (GPI-ecto-TβRII) lacking the transmembrane and cytoplasmic signaling domain of TGF-β receptor II (TβRII). T cells transduced with lentivirus expressing the GPI-ecto-TβRII construct show 5 to 15 times higher membrane expression compared with a previously established dominant-negative receptor carrying a truncated signaling domain. GPI-ecto-TβRII expression renders T cells unresponsive to TGF-β-induced signaling seen by a lack of SMAD phosphorylation upon exogeneous TGF-β treatment. Transduced T cells continue to express high levels of IFNγ and granulocyte-macrophage colony-stimulating factor (GM-CSF), among other cytokines, in the presence of TGF-β while cytokine expression in untransduced T cells is being markedly suppressed. Furthermore, T cells expressing GPI-ecto-TβRII constructs have been shown to efficiently capture and inactivate TGF-β from their environment. These results indicate the potential benefits of GPI-ecto-TβRII expressing cytotoxic T cells (CTLs) in future cell therapies.
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Affiliation(s)
| | | | | | - Dang L. Vu
- Tessa Therapeutics, Singapore, Singapore
- Program in Translational Immunology, Institute of Molecular and Cell Biology, A∗STAR, Singapore, Singapore
| | | | - Sonia M.P. Maia
- Tessa Therapeutics, Singapore, Singapore
- Program in Translational Immunology, Institute of Molecular and Cell Biology, A∗STAR, Singapore, Singapore
| | - John E. Connolly
- Tessa Therapeutics, Singapore, Singapore
- Program in Translational Immunology, Institute of Molecular and Cell Biology, A∗STAR, Singapore, Singapore
- Department of Microbiology and Immunity, National University of Singapore, Singapore, Singapore
- Institute of Biomedical Studies, Baylor University Medical Center, Waco, TX, USA
- Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA
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4
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Fernández-Aguilar LM, Vico-Barranco I, Arbulo-Echevarria MM, Aguado E. A Story of Kinases and Adaptors: The Role of Lck, ZAP-70 and LAT in Switch Panel Governing T-Cell Development and Activation. BIOLOGY 2023; 12:1163. [PMID: 37759563 PMCID: PMC10525366 DOI: 10.3390/biology12091163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/18/2023] [Accepted: 08/20/2023] [Indexed: 09/29/2023]
Abstract
Specific antigen recognition is one of the immune system's features that allows it to mount intense yet controlled responses to an infinity of potential threats. T cells play a relevant role in the host defense and the clearance of pathogens by means of the specific recognition of peptide antigens presented by antigen-presenting cells (APCs), and, to do so, they are equipped with a clonally distributed antigen receptor called the T-cell receptor (TCR). Upon the specific engagement of the TCR, multiple intracellular signals are triggered, which lead to the activation, proliferation and differentiation of T lymphocytes into effector cells. In addition, this signaling cascade also operates during T-cell development, allowing for the generation of cells that can be helpful in the defense against threats, as well as preventing the generation of autoreactive cells. Early TCR signals include phosphorylation events in which the tyrosine kinases Lck and ZAP70 are involved. The sequential activation of these kinases leads to the phosphorylation of the transmembrane adaptor LAT, which constitutes a signaling hub for the generation of a signalosome, finally resulting in T-cell activation. These early signals play a relevant role in triggering the development, activation, proliferation and apoptosis of T cells, and the negative regulation of these signals is key to avoid aberrant processes that could generate inappropriate cellular responses and disease. In this review, we will examine and discuss the roles of the tyrosine kinases Lck and ZAP70 and the membrane adaptor LAT in these cellular processes.
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Grants
- PY20_01297 Consejería de Transformación Económica, Industria, Conocimiento y Universidades, Junta de Andalucía, Spain
- PID2020-113943RB-I00 Agencia Estatal de Investigación, Ministerio de Ciencia e Innovación, Spain
- PR2022-037 University of Cádiz
- PAIDI2020/DOC_01433 Consejería de Transformación Económica, Industria, Conocimiento y Universidades, Junta de Andalucía, Spain
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Affiliation(s)
- Luis M. Fernández-Aguilar
- Institute for Biomedical Research of Cadiz (INIBICA), 11009 Cadiz, Spain; (L.M.F.-A.); (I.V.-B.); (M.M.A.-E.)
- Department of Biomedicine, Biotechnology and Public Health (Immunology), University of Cadiz, 11002 Cadiz, Spain
| | - Inmaculada Vico-Barranco
- Institute for Biomedical Research of Cadiz (INIBICA), 11009 Cadiz, Spain; (L.M.F.-A.); (I.V.-B.); (M.M.A.-E.)
- Department of Biomedicine, Biotechnology and Public Health (Immunology), University of Cadiz, 11002 Cadiz, Spain
| | - Mikel M. Arbulo-Echevarria
- Institute for Biomedical Research of Cadiz (INIBICA), 11009 Cadiz, Spain; (L.M.F.-A.); (I.V.-B.); (M.M.A.-E.)
- Department of Biomedicine, Biotechnology and Public Health (Immunology), University of Cadiz, 11002 Cadiz, Spain
| | - Enrique Aguado
- Institute for Biomedical Research of Cadiz (INIBICA), 11009 Cadiz, Spain; (L.M.F.-A.); (I.V.-B.); (M.M.A.-E.)
- Department of Biomedicine, Biotechnology and Public Health (Immunology), University of Cadiz, 11002 Cadiz, Spain
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5
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Chen E, Mo Y, Yi J, Liu J, Luo T, Li Z, Lin Z, Hu Y, Zou Z, Liu J. A novel hepatocellular carcinoma-specific mTORC1-related signature for anticipating prognosis and immunotherapy. Aging (Albany NY) 2023; 15:7933-7955. [PMID: 37589508 PMCID: PMC10497017 DOI: 10.18632/aging.204862] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 06/09/2023] [Indexed: 08/18/2023]
Abstract
Tumor oncogenesis, cancer metastasis, and immune evasion were substantially impacted by the mammalian target of the rapamycin complex 1 (mTORC1) pathway. However, in hepatocellular carcinoma (HCC), no mTORC1 signaling-based gene signature has ever been published. mTORC1 scores were computed employing a single sample gene set enrichment analysis based on databases including the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). The PAG1, LHFPL2, and FABP5 expression levels were obtained to construct a mTORC1 pathway-related model. In two databases, the overall survival (OS) rate was shorter for high-mTORC1 score patients compared to those with low scores. The activation of TFs in the group with high risk was enhanced, such as the HIF-1 pathway. Additionally, it was discovered that a high mTORC1 score was linked to an immune exclusion phenotype and enhanced immunosuppressive cell infiltration. Notably, it was discovered that high-mTORC1 scores patients had poorer immunotherapeutic results and might not gain benefit from immunotherapy. When compared to the low HCC metastatic cell lines, the high HCC metastatic cell lines have overexpressed levels of PAG1, LHFPL2, and FABP5 expression. The expression of PAG1, LHFPL2, and FABP5 was inhibited by the MAPK and mTORC1 pathway inhibitors. Our study identified mTORC1 score signature can aid in the development of individualized immunotherapy protocols and predict the HCC patients' prognoses.
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Affiliation(s)
- Erbao Chen
- Department of Hepatobiliary and Pancreatic Surgery, Peking University Shenzhen Hospital, Shenzhen, Guangdong, China
| | - Yuqian Mo
- School of Public Health, Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Jing Yi
- Department of Hepatobiliary and Pancreatic Surgery, Peking University Shenzhen Hospital, Shenzhen, Guangdong, China
| | - Jie Liu
- Department of Hepatobiliary and Pancreatic Surgery, Peking University Shenzhen Hospital, Shenzhen, Guangdong, China
| | - Ting Luo
- Operating Room, Peking University Shenzhen Hospital, Shenzhen, Guangdong, China
| | - Zheng Li
- Department of Ophthalmology, Affiliated Eye Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zewei Lin
- Department of Hepatobiliary and Pancreatic Surgery, Peking University Shenzhen Hospital, Shenzhen, Guangdong, China
| | - Yibing Hu
- Breast and Thyroid Surgery, Peking University Shenzhen Hospital, Shenzhen, Guangdong, China
| | - Zhilin Zou
- Department of Ophthalmology, Affiliated Eye Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jikui Liu
- Department of Hepatobiliary and Pancreatic Surgery, Peking University Shenzhen Hospital, Shenzhen, Guangdong, China
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6
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Fortner A, Chera A, Tanca A, Bucur O. Apoptosis regulation by the tyrosine-protein kinase CSK. Front Cell Dev Biol 2022; 10:1078180. [PMID: 36578781 PMCID: PMC9792154 DOI: 10.3389/fcell.2022.1078180] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 11/24/2022] [Indexed: 12/14/2022] Open
Abstract
C-terminal Src kinase (CSK) is a cytosolic tyrosine-protein kinase with an important role in regulating critical cellular decisions, such as cellular apoptosis, survival, proliferation, cytoskeletal organization and many others. Current knowledge on the CSK mechanisms of action, regulation and functions is still at an early stage, most of CSK's known actions and functions being mediated by the negative regulation of the SRC family of tyrosine kinases (SFKs) through phosphorylation. As SFKs play a vital role in apoptosis, cell proliferation and survival regulation, SFK inhibition by CSK has a pro-apoptotic effect, which is mediated by the inhibition of cellular signaling cascades controlled by SFKs, such as the MAPK/ERK, STAT3 and PI3K/AKT signaling pathways. Abnormal functioning of CSK and SFK activation can lead to diseases such as cancer, cardiovascular and neurological manifestations. This review describes apoptosis regulation by CSK, CSK inhibition of the SFKs and further explores the clinical relevance of CSK in important pathologies, such as cancer, autoimmune, autoinflammatory, neurologic diseases, hypertension and HIV/AIDS.
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Affiliation(s)
- Andra Fortner
- Victor Babes National Institute of Pathology, Bucharest, Romania,Medical School, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
| | - Alexandra Chera
- Victor Babes National Institute of Pathology, Bucharest, Romania,Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Antoanela Tanca
- Victor Babes National Institute of Pathology, Bucharest, Romania,Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania,*Correspondence: Octavian Bucur, ; Antoanela Tanca,
| | - Octavian Bucur
- Victor Babes National Institute of Pathology, Bucharest, Romania,Viron Molecular Medicine Institute, Boston, MA, United States,*Correspondence: Octavian Bucur, ; Antoanela Tanca,
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7
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Shannon N, Gravelle R, Cunniff B. Mitochondrial trafficking and redox/phosphorylation signaling supporting cell migration phenotypes. Front Mol Biosci 2022; 9:925755. [PMID: 35936783 PMCID: PMC9355248 DOI: 10.3389/fmolb.2022.925755] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 07/05/2022] [Indexed: 11/13/2022] Open
Abstract
Regulation of cell signaling cascades is critical in making sure the response is activated spatially and for a desired duration. Cell signaling cascades are spatially and temporally controlled through local protein phosphorylation events which are determined by the activation of specific kinases and/or inactivation of phosphatases to elicit a complete and thorough response. For example, A-kinase-anchoring proteins (AKAPs) contribute to the local regulated activity protein kinase A (PKA). The activity of kinases and phosphatases can also be regulated through redox-dependent cysteine modifications that mediate the activity of these proteins. A primary example of this is the activation of the epidermal growth factor receptor (EGFR) and the inactivation of the phosphatase and tensin homologue (PTEN) phosphatase by reactive oxygen species (ROS). Therefore, the local redox environment must play a critical role in the timing and magnitude of these events. Mitochondria are a primary source of ROS and energy (ATP) that contributes to redox-dependent signaling and ATP-dependent phosphorylation events, respectively. The strategic positioning of mitochondria within cells contributes to intracellular gradients of ROS and ATP, which have been shown to correlate with changes to protein redox and phosphorylation status driving downstream cellular processes. In this review, we will discuss the relationship between subcellular mitochondrial positioning and intracellular ROS and ATP gradients that support dynamic oxidation and phosphorylation signaling and resulting cellular effects, specifically associated with cell migration signaling.
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Affiliation(s)
- Nathaniel Shannon
- Department of Pathology and Laboratory Medicine, Redox Biology Program, University of Vermont Larner College of Medicine, Burlington, VT, United States
| | - Randi Gravelle
- Department of Pathology and Laboratory Medicine, Redox Biology Program, University of Vermont Larner College of Medicine, Burlington, VT, United States
| | - Brian Cunniff
- Department of Pathology and Laboratory Medicine, Redox Biology Program, University of Vermont Larner College of Medicine, Burlington, VT, United States
- University of Vermont Cancer Center, University of Vermont Larner College of Medicine, Burlington, VT, United States
- *Correspondence: Brian Cunniff,
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8
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Moore EK, Strazza M, Mor A. Combination Approaches to Target PD-1 Signaling in Cancer. Front Immunol 2022; 13:927265. [PMID: 35911672 PMCID: PMC9330480 DOI: 10.3389/fimmu.2022.927265] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 06/23/2022] [Indexed: 11/13/2022] Open
Abstract
Cancer remains the second leading cause of death in the US, accounting for 25% of all deaths nationwide. Immunotherapy techniques bolster the immune cells' ability to target malignant cancer cells and have brought immense improvements in the field of cancer treatments. One important inhibitory protein in T cells, programmed cell death protein 1 (PD-1), has become an invaluable target for cancer immunotherapy. While anti-PD-1 antibody therapy is extremely successful in some patients, in others it fails or even causes further complications, including cancer hyper-progression and immune-related adverse events. Along with countless translational studies of the PD-1 signaling pathway, there are currently close to 5,000 clinical trials for antibodies against PD-1 and its ligand, PD-L1, around 80% of which investigate combinations with other therapies. Nevertheless, more work is needed to better understand the PD-1 signaling pathway and to facilitate new and improved evidence-based combination strategies. In this work, we consolidate recent discoveries of PD-1 signaling mediators and their therapeutic potential in combination with anti-PD-1/PD-L1 agents. We focus on the phosphatases SHP2 and PTPN2; the kinases ITK, VRK2, GSK-3, and CDK4/6; and the signaling adaptor protein PAG. We discuss their biology both in cancer cells and T cells, with a focus on their role in relation to PD-1 to determine their potential in therapeutic combinations. The literature discussed here was obtained from a search of the published literature and ClinicalTrials.gov with the following key terms: checkpoint inhibition, cancer immunotherapy, PD-1, PD-L1, SHP2, PTPN2, ITK, VRK2, CDK4/6, GSK-3, and PAG. Together, we find that all of these proteins are logical and promising targets for combination therapy, and that with a deeper mechanistic understanding they have potential to improve the response rate and decrease adverse events when thoughtfully used in combination with checkpoint inhibitors.
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Affiliation(s)
- Emily K. Moore
- Division of Rheumatology, Department of Medicine, Columbia University Medical Center, New York, NY, United States
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, United States
| | - Marianne Strazza
- Division of Rheumatology, Department of Medicine, Columbia University Medical Center, New York, NY, United States
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, United States
| | - Adam Mor
- Division of Rheumatology, Department of Medicine, Columbia University Medical Center, New York, NY, United States
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, United States
- Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY, United States
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9
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Brian BF, Sjaastad FV, Freedman TS. SH3-domain mutations selectively disrupt Csk homodimerization or PTPN22 binding. Sci Rep 2022; 12:5875. [PMID: 35393453 PMCID: PMC8989918 DOI: 10.1038/s41598-022-09589-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 03/25/2022] [Indexed: 12/16/2022] Open
Abstract
The kinase Csk is the primary negative regulator of the Src-family kinases (SFKs, e.g., Lck, Fyn, Lyn, Hck, Fgr, Blk, Yes), phosphorylating a tyrosine on the SFK C-terminal tail that mediates autoinhibition. Csk also binds phosphatases, including PTPN12 (PTP-PEST) and immune-cell PTPN22 (LYP/Pep), which dephosphorylate the SFK activation loop to promote autoinhibition. Csk-binding proteins (e.g., CBP/PAG1) oligomerize within membrane microdomains, and high local concentration promotes Csk function. Purified Csk homodimerizes in solution through an interface that overlaps the phosphatase binding footprint. Here we demonstrate that Csk can homodimerize in Jurkat T cells, in competition with PTPN22 binding. We designed SH3-domain mutations in Csk that selectively impair homodimerization (H21I) or PTPN22 binding (K43D) and verified their kinase activity in solution. Disruption of either interaction in cells, however, decreased the negative-regulatory function of Csk. Csk W47A, a substitution previously reported to block PTPN22 binding, had a secondary effect of impairing homodimerization. Csk H21I and K43D will be useful tools for dissecting the protein-specific drivers of autoimmunity mediated by the human polymorphism PTPN22 R620W, which impairs interaction with Csk and with the E3 ubiquitin ligase TRAF3. Future investigations of Csk homodimer activity and phosphatase interactions may reveal new facets of SFK regulation in hematopoietic and non-hematopoietic cells.
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Affiliation(s)
- Ben F Brian
- Graduate Program in Molecular Pharmacology and Therapeutics, University of Minnesota, Minneapolis, MN, 55455, USA.,Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, 94170, USA
| | - Frances V Sjaastad
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, 55455, USA.,Department of Cardiac Rhythm Management, Medtronic, Mounds View, MN, 55112, USA
| | - Tanya S Freedman
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, 55455, USA. .,Center for Immunology, University of Minnesota, Minneapolis, MN, 55455, USA. .,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, 55455, USA. .,Center for Autoimmune Diseases Research, University of Minnesota, Minneapolis, MN, 55455, USA.
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10
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Shah K, Al-Haidari A, Sun J, Kazi JU. T cell receptor (TCR) signaling in health and disease. Signal Transduct Target Ther 2021; 6:412. [PMID: 34897277 PMCID: PMC8666445 DOI: 10.1038/s41392-021-00823-w] [Citation(s) in RCA: 153] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 11/02/2021] [Accepted: 11/02/2021] [Indexed: 12/18/2022] Open
Abstract
Interaction of the T cell receptor (TCR) with an MHC-antigenic peptide complex results in changes at the molecular and cellular levels in T cells. The outside environmental cues are translated into various signal transduction pathways within the cell, which mediate the activation of various genes with the help of specific transcription factors. These signaling networks propagate with the help of various effector enzymes, such as kinases, phosphatases, and phospholipases. Integration of these disparate signal transduction pathways is done with the help of adaptor proteins that are non-enzymatic in function and that serve as a scaffold for various protein-protein interactions. This process aids in connecting the proximal to distal signaling pathways, thereby contributing to the full activation of T cells. This review provides a comprehensive snapshot of the various molecules involved in regulating T cell receptor signaling, covering both enzymes and adaptors, and will discuss their role in human disease.
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Affiliation(s)
- Kinjal Shah
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University, Lund, Sweden
- Lund Stem Cell Center, Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Amr Al-Haidari
- Clinical Genetics and Pathology, Skåne University Hospital, Region Skåne, Lund, Sweden
- Clinical Sciences Department, Surgery Research Unit, Lund University, Malmö, Sweden
| | - Jianmin Sun
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University, Lund, Sweden
- Lund Stem Cell Center, Department of Laboratory Medicine, Lund University, Lund, Sweden
- NHC Key Laboratory of Metabolic Cardiovascular Diseases Research, Science and Technology center, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, China
| | - Julhash U Kazi
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University, Lund, Sweden.
- Lund Stem Cell Center, Department of Laboratory Medicine, Lund University, Lund, Sweden.
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11
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Zhang Y, Qin Z, Sun W, Chu F, Zhou F. Function of Protein S-Palmitoylation in Immunity and Immune-Related Diseases. Front Immunol 2021; 12:661202. [PMID: 34557182 PMCID: PMC8453015 DOI: 10.3389/fimmu.2021.661202] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 08/23/2021] [Indexed: 02/04/2023] Open
Abstract
Protein S-palmitoylation is a covalent and reversible lipid modification that specifically targets cysteine residues within many eukaryotic proteins. In mammalian cells, the ubiquitous palmitoyltransferases (PATs) and serine hydrolases, including acyl protein thioesterases (APTs), catalyze the addition and removal of palmitate, respectively. The attachment of palmitoyl groups alters the membrane affinity of the substrate protein changing its subcellular localization, stability, and protein-protein interactions. Forty years of research has led to the understanding of the role of protein palmitoylation in significantly regulating protein function in a variety of biological processes. Recent global profiling of immune cells has identified a large body of S-palmitoylated immunity-associated proteins. Localization of many immune molecules to the cellular membrane is required for the proper activation of innate and adaptive immune signaling. Emerging evidence has unveiled the crucial roles that palmitoylation plays to immune function, especially in partitioning immune signaling proteins to the membrane as well as to lipid rafts. More importantly, aberrant PAT activity and fluctuations in palmitoylation levels are strongly correlated with human immunologic diseases, such as sensory incompetence or over-response to pathogens. Therefore, targeting palmitoylation is a novel therapeutic approach for treating human immunologic diseases. In this review, we discuss the role that palmitoylation plays in both immunity and immunologic diseases as well as the significant potential of targeting palmitoylation in disease treatment.
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12
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Kralova J, Pavliuchenko N, Fabisik M, Ilievova K, Spoutil F, Prochazka J, Pokorna J, Sedlacek R, Brdicka T. The receptor-type protein tyrosine phosphatase CD45 promotes onset and severity of IL-1β-mediated autoinflammatory osteomyelitis. J Biol Chem 2021; 297:101131. [PMID: 34461100 PMCID: PMC8455366 DOI: 10.1016/j.jbc.2021.101131] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 08/20/2021] [Accepted: 08/26/2021] [Indexed: 11/17/2022] Open
Abstract
A number of human autoinflammatory diseases manifest with severe inflammatory bone destruction. Mouse models of these diseases represent valuable tools that help us to understand molecular mechanisms triggering this bone autoinflammation. The Pstpip2cmo mouse strain is among the best characterized of these; it harbors a mutation resulting in the loss of adaptor protein PSTPIP2 and development of autoinflammatory osteomyelitis. In Pstpip2cmo mice, overproduction of interleukin-1β (IL-1β) and reactive oxygen species by neutrophil granulocytes leads to spontaneous inflammation of the bones and surrounding soft tissues. However, the upstream signaling events leading to this overproduction are poorly characterized. Here, we show that Pstpip2cmo mice deficient in major regulator of Src-family kinases (SFKs) receptor-type protein tyrosine phosphatase CD45 display delayed onset and lower severity of the disease, while the development of autoinflammation is not affected by deficiencies in Toll-like receptor signaling. Our data also show deregulation of pro-IL-1β production by Pstpip2cmo neutrophils that are attenuated by CD45 deficiency. These data suggest a role for SFKs in autoinflammation. Together with previously published work on the involvement of protein tyrosine kinase spleen tyrosine kinase, they point to the role of receptors containing immunoreceptor tyrosine-based activation motifs, which after phosphorylation by SFKs recruit spleen tyrosine kinase for further signal propagation. We propose that this class of receptors triggers the events resulting in increased pro-IL-1β synthesis and disease initiation and/or progression.
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Affiliation(s)
- Jarmila Kralova
- Laboratory of Leukocyte Signaling, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Nataliia Pavliuchenko
- Laboratory of Leukocyte Signaling, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic; Charles University, Faculty of Science, Prague, Czech Republic
| | - Matej Fabisik
- Laboratory of Leukocyte Signaling, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic; Charles University, Faculty of Science, Prague, Czech Republic
| | - Kristyna Ilievova
- Laboratory of Leukocyte Signaling, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Frantisek Spoutil
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vestec, Czech Republic
| | - Jan Prochazka
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vestec, Czech Republic; Laboratory of Transgenic Models of Diseases, Institute of Molecular Genetics of the Czech Academy of Sciences, Vestec, Czech Republic
| | - Jana Pokorna
- Laboratory of Leukocyte Signaling, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Radislav Sedlacek
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vestec, Czech Republic; Laboratory of Transgenic Models of Diseases, Institute of Molecular Genetics of the Czech Academy of Sciences, Vestec, Czech Republic
| | - Tomas Brdicka
- Laboratory of Leukocyte Signaling, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic.
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13
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Messad F, Louveau I, Renaudeau D, Gilbert H, Gondret F. Analysis of merged whole blood transcriptomic datasets to identify circulating molecular biomarkers of feed efficiency in growing pigs. BMC Genomics 2021; 22:501. [PMID: 34217223 PMCID: PMC8254903 DOI: 10.1186/s12864-021-07843-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 06/24/2021] [Indexed: 11/10/2022] Open
Abstract
Background Improving feed efficiency (FE) is an important goal due to its economic and environmental significance for farm animal production. The FE phenotype is complex and based on the measurements of the individual feed consumption and average daily gain during a test period, which is costly and time-consuming. The identification of reliable predictors of FE is a strategy to reduce phenotyping efforts. Results Gene expression data of the whole blood from three independent experiments were combined and analyzed by machine learning algorithms to propose molecular biomarkers of FE traits in growing pigs. These datasets included Large White pigs from two lines divergently selected for residual feed intake (RFI), a measure of net FE, and in which individual feed conversion ratio (FCR) and blood microarray data were available. Merging the three datasets allowed considering FCR values (Mean = 2.85; Min = 1.92; Max = 5.00) for a total of n = 148 pigs, with a large range of body weight (15 to 115 kg) and different test period duration (2 to 9 weeks). Random forest (RF) and gradient tree boosting (GTB) were applied on the whole blood transcripts (26,687 annotated molecular probes) to identify the most important variables for binary classification on RFI groups and a quantitative prediction of FCR, respectively. The dataset was split into learning (n = 74) and validation sets (n = 74). With iterative steps for variable selection, about three hundred’s (328 to 391) molecular probes participating in various biological pathways, were identified as important predictors of RFI or FCR. With the GTB algorithm, simpler models were proposed combining 34 expressed unique genes to classify pigs into RFI groups (100% of success), and 25 expressed unique genes to predict FCR values (R2 = 0.80, RMSE = 8%). The accuracy performance of RF models was slightly lower in classification and markedly lower in regression. Conclusion From small subsets of genes expressed in the whole blood, it is possible to predict the binary class and the individual value of feed efficiency. These predictive models offer good perspectives to identify animals with higher feed efficiency in precision farming applications. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07843-4.
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Affiliation(s)
- Farouk Messad
- PEGASE, INRAE, Institut Agro, 35590, Saint-Gilles, France
| | | | | | - Hélène Gilbert
- GenPhySE, INRAE, INP-ENVT, 31326, Castanet Tolosan, France
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14
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Strazza M, Azoulay-Alfaguter I, Peled M, Adam K, Mor A. Transmembrane adaptor protein PAG is a mediator of PD-1 inhibitory signaling in human T cells. Commun Biol 2021; 4:672. [PMID: 34083754 PMCID: PMC8175585 DOI: 10.1038/s42003-021-02225-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 04/29/2021] [Indexed: 12/15/2022] Open
Abstract
The inhibitory receptor PD-1 is expressed on T cells to inhibit select functions when ligated. The complete signaling mechanism downstream of PD-1 has yet to be uncovered. Here, we discovered phosphoprotein associated with glycosphingolipid-enriched microdomains 1 (PAG) is phosphorylated following PD-1 ligation and associate this with inhibitory T cell function. Clinical cohort analysis correlates low PAG expression with increased survival from numerous tumor types. PAG knockdown in T cells prevents PD-1-mediated inhibition of cytokine secretion, cell adhesion, CD69 expression, and ERK204/187 phosphorylation, and enhances phosphorylation of SRC527 following PD-1 ligation. PAG overexpression rescues these effects. In vivo, PAG contributes greatly to the growth of two murine tumors, MC38 and B16, and limits T cell presence within the tumor. Moreover, PAG deletion sensitizes tumors to PD-1 blockade. Here PAG is established as a critical mediator of PD-1 signaling and as a potential target to enhance T cell activation in tumors.
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MESH Headings
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- Antigens, CD/metabolism
- Antigens, Differentiation, T-Lymphocyte/metabolism
- Cell Line, Tumor
- Cells, Cultured
- Cytokines/metabolism
- Humans
- Lectins, C-Type/metabolism
- Lymphocyte Activation
- Male
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice, Inbred C57BL
- Mice, Knockout
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/metabolism
- Neoplasms, Experimental/pathology
- Phosphorylation
- Programmed Cell Death 1 Receptor/genetics
- Programmed Cell Death 1 Receptor/metabolism
- Signal Transduction
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
- Mice
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Affiliation(s)
- Marianne Strazza
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | | | - Michael Peled
- Perlmutter Cancer Center, New York University School of Medicine, New York, NY, USA
| | - Kieran Adam
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA
| | - Adam Mor
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY, USA.
- Division of Rheumatology, Department of Medicine, Columbia University Medical Center, New York, NY, USA.
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15
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Influence of pentoxifylline on gene expression of PAG1/ miR-1206/ SNHG14 in ischemic heart disease. Biochem Biophys Rep 2021; 25:100911. [PMID: 33553684 PMCID: PMC7846894 DOI: 10.1016/j.bbrep.2021.100911] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 12/14/2020] [Accepted: 01/06/2021] [Indexed: 12/12/2022] Open
Abstract
The regulation by immune checkpoint is able to prevent excessive tissue damage caused by ischemia reperfusion (I/R); therefore, the study aims to investigate the behavior of phosphoprotein associated with glycosphingolipid-enriched microdomains 1 (PAG1) mRNA, miR-1206 and small nucleolar RNA host gene 14 (SNHG14) during I/R and intake of pentoxifylline (PTX) as a protective drug. The relative expression level of PAG1/miR-1206/SNHG14 was determined by qRT-PCR. Cardiac tissue levels of cytotoxic T-lymphocyte associated antigen 4 (CTLA4) and PAG1 protein expression were determined by ELISA technique. The regulatory T cells achieved by the flow cytometry. The results found that the relative expression of SNHG14 was significantly upregulated in I/R, but suppressed in PTX treated groups with enhancement of the relative expression level of miR-1206. The gene and protein expression of PAG1 were downregulated with effective doses of PTX. The results showed that (30 and 40 mg/kg bwt) PTX dose suppressed the CTLA4 development significantly. The mean of the regulatory T cell in PTX protective groups is significantly reduced at (p < 0.001) in a comparison with I/R group. Spearman's correlation analysis revealed a significant negative correlation between SNHG14 and miR-1206, but a significant positive correlation between SNHG14 and PAG1 in I/R heart tissue. The results indicated that miR-1206 and SNHG14 can be used as biomarkers with perfect sensitivity and specificity. Using PTX reduced cardiac tissue damage. SNHG14 and miR-1206 can be used as a diagnostic tool in I/R. Positive correlation between SNHG14 and PAG1 relative expression in I/R heart tissues. SNHG14 and miR-1206 can be used as a diagnostic tool in ischemia reperfusion. Negative correlation between SNHG14 and miR-1206. Using pentoxifylline as a protective drug renders cardiac tissues more resistance to ischemia.
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16
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Kim HR, Park JS, Fatima Y, Kausar M, Park JH, Jun CD. Potentiating the Antitumor Activity of Cytotoxic T Cells via the Transmembrane Domain of IGSF4 That Increases TCR Avidity. Front Immunol 2021; 11:591054. [PMID: 33597944 PMCID: PMC7882689 DOI: 10.3389/fimmu.2020.591054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 12/14/2020] [Indexed: 01/25/2023] Open
Abstract
A robust T-cell response is an important component of sustained antitumor immunity. In this respect, the avidity of TCR in the antigen-targeting of tumors is crucial for the quality of the T-cell response. This study reports that the transmembrane (TM) domain of immunoglobulin superfamily member 4 (IGSF4) binds to the TM of the CD3 ζ-chain through an interaction between His177 and Asp36, which results in IGSF4-CD3 ζ dimers. IGSF4 also forms homo-dimers through the GxxVA motif in the TM domain, thereby constituting large TCR clusters. Overexpression of IGSF4 lacking the extracellular (IG4ΔEXT) domain potentiates the OTI CD8+ T cells to release IFN-γ and TNF-α and to kill OVA+-B16F10 melanoma cells. In animal models, IG4ΔEXT significantly reduces B16F10 tumor metastasis as well as tumor growth. Collectively, the results indicate that the TM domain of IGSF4 can regulate TCR avidity, and they further demonstrate that TCR avidity regulation is critical for improving the antitumor activity of cytotoxic T cells.
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MESH Headings
- Animals
- Cell Adhesion Molecule-1/genetics
- Cell Adhesion Molecule-1/immunology
- Cell Line, Tumor
- Humans
- Immunotherapy
- Melanoma, Experimental/immunology
- Melanoma, Experimental/pathology
- Melanoma, Experimental/therapy
- Mice, Inbred C57BL
- Mice, Transgenic
- Protein Domains
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
- T-Lymphocytes/immunology
- Mice
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Affiliation(s)
- Hye-Ran Kim
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
- Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Jeong-Su Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
- Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Yasmin Fatima
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
- Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Maiza Kausar
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
- Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Jin-Hwa Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
- Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Chang-Duk Jun
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
- Immune Synapse and Cell Therapy Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
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17
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Multi-color Molecular Visualization of Signaling Proteins Reveals How C-Terminal Src Kinase Nanoclusters Regulate T Cell Receptor Activation. Cell Rep 2020; 33:108523. [PMID: 33357425 DOI: 10.1016/j.celrep.2020.108523] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 07/07/2020] [Accepted: 11/24/2020] [Indexed: 11/22/2022] Open
Abstract
Elucidating the mechanisms that controlled T cell activation requires visualization of the spatial organization of multiple proteins on the submicron scale. Here, we use stoichiometrically accurate, multiplexed, single-molecule super-resolution microscopy (DNA-PAINT) to image the nanoscale spatial architecture of the primary inhibitor of the T cell signaling pathway, Csk, and two binding partners implicated in its membrane association, PAG and TRAF3. Combined with a newly developed co-clustering analysis framework, we find that Csk forms nanoscale clusters proximal to the plasma membrane that are lost post-stimulation and are re-recruited at later time points. Unexpectedly, these clusters do not co-localize with PAG at the membrane but instead provide a ready pool of monomers to downregulate signaling. By generating CRISPR-Cas9 knockout T cells, our data also identify that a major risk factor for autoimmune diseases, the protein tyrosine phosphatase non-receptor type 22 (PTPN22) locus, is essential for Csk nanocluster re-recruitment and for maintenance of the synaptic PAG population.
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18
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Castro-Sanchez P, Teagle AR, Prade S, Zamoyska R. Modulation of TCR Signaling by Tyrosine Phosphatases: From Autoimmunity to Immunotherapy. Front Cell Dev Biol 2020; 8:608747. [PMID: 33425916 PMCID: PMC7793860 DOI: 10.3389/fcell.2020.608747] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 11/18/2020] [Indexed: 02/06/2023] Open
Abstract
Early TCR signaling is dependent on rapid phosphorylation and dephosphorylation of multiple signaling and adaptor proteins, leading to T cell activation. This process is tightly regulated by an intricate web of interactions between kinases and phosphatases. A number of tyrosine phosphatases have been shown to modulate T cell responses and thus alter T cell fate by negatively regulating early TCR signaling. Mutations in some of these enzymes are associated with enhanced predisposition to autoimmunity in humans, and mouse models deficient in orthologous genes often show T cell hyper-activation. Therefore, phosphatases are emerging as potential targets in situations where it is desirable to enhance T cell responses, such as immune responses to tumors. In this review, we summarize the current knowledge about tyrosine phosphatases that regulate early TCR signaling and discuss their involvement in autoimmunity and their potential as targets for tumor immunotherapy.
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Affiliation(s)
- Patricia Castro-Sanchez
- Ashworth Laboratories, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Alexandra R Teagle
- Ashworth Laboratories, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Sonja Prade
- Ashworth Laboratories, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Rose Zamoyska
- Ashworth Laboratories, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
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19
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Yang X, Chatterjee V, Ma Y, Zheng E, Yuan SY. Protein Palmitoylation in Leukocyte Signaling and Function. Front Cell Dev Biol 2020; 8:600368. [PMID: 33195285 PMCID: PMC7655920 DOI: 10.3389/fcell.2020.600368] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 09/30/2020] [Indexed: 12/12/2022] Open
Abstract
Palmitoylation is a post-translational modification (PTM) based on thioester-linkage between palmitic acid and the cysteine residue of a protein. This covalent attachment of palmitate is reversibly and dynamically regulated by two opposing sets of enzymes: palmitoyl acyltransferases containing a zinc finger aspartate-histidine-histidine-cysteine motif (PAT-DHHCs) and thioesterases. The reversible nature of palmitoylation enables fine-tuned regulation of protein conformation, stability, and ability to interact with other proteins. More importantly, the proper function of many surface receptors and signaling proteins requires palmitoylation-meditated partitioning into lipid rafts. A growing number of leukocyte proteins have been reported to undergo palmitoylation, including cytokine/chemokine receptors, adhesion molecules, pattern recognition receptors, scavenger receptors, T cell co-receptors, transmembrane adaptor proteins, and signaling effectors including the Src family of protein kinases. This review provides the latest findings of palmitoylated proteins in leukocytes and focuses on the functional impact of palmitoylation in leukocyte function related to adhesion, transmigration, chemotaxis, phagocytosis, pathogen recognition, signaling activation, cytotoxicity, and cytokine production.
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Affiliation(s)
- Xiaoyuan Yang
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Victor Chatterjee
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Yonggang Ma
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Ethan Zheng
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Sarah Y Yuan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States.,Department of Surgery, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
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20
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Yurtsever D, Lorent JH. Structural Modifications Controlling Membrane Raft Partitioning and Curvature in Human and Viral Proteins. J Phys Chem B 2020; 124:7574-7585. [PMID: 32813532 PMCID: PMC7476027 DOI: 10.1021/acs.jpcb.0c03435] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Membrane
proteins and lipids have the capacity to associate into
lateral domains in cell membranes through mutual or collective interactions.
Lipid rafts are functional lateral domains that are formed through
collective interactions of certain lipids and which can include or
exclude proteins. These domains have been implicated in cell signaling
and protein trafficking and seem to be of importance for virus–host
interactions. We therefore want to investigate if raft and viral membrane
proteins present similar structural features, and how these features
are distributed throughout viruses. For this purpose, we performed
a bioinformatics analysis of raft and viral membrane proteins from
available online databases and compared them to nonraft proteins.
In general, transmembrane proteins of rafts and viruses had higher
proportions of palmitoyl and phosphoryl residues compared to nonraft
proteins. They differed in terms of transmembrane domain length and
thickness, with viral proteins being generally shorter and having
a smaller accessible surface area per residue. Nontransmembrane raft
proteins had increased amounts of palmitoyl, prenyl, and phosphoryl
moieties while their viral counterparts were largely myristoylated
and phosphorylated. Several of these structural determinants such
as phosphorylation are new to the raft field and are extensively discussed
in terms of raft functionality and phase separation. Surprisingly,
the proportion of palmitoylated viral transmembrane proteins was inversely
correlated to the virus size which indicated the implication of palmitoylation
in virus membrane curvature and possibly budding. The current results
provide new insights into the raft–virus interplay and unveil
possible targets for antiviral compounds.
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Affiliation(s)
- Deniz Yurtsever
- Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, Padualaan 8, NL-3584CH Utrecht, The Netherlands
| | - Joseph Helmuth Lorent
- Membrane Biochemistry & Biophysics, Bijvoet Center for Biomolecular Research, Department of Chemistry, Utrecht University, Padualaan 8, NL-3584CH Utrecht, The Netherlands
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21
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Wu W, Zhou Q, Masubuchi T, Shi X, Li H, Xu X, Huang M, Meng L, He X, Zhu H, Gao S, Zhang N, Jing R, Sun J, Wang H, Hui E, Wong CC, Xu C. Multiple Signaling Roles of CD3ε and Its Application in CAR-T Cell Therapy. Cell 2020; 182:855-871.e23. [PMID: 32730808 DOI: 10.1016/j.cell.2020.07.018] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/28/2020] [Accepted: 07/14/2020] [Indexed: 01/17/2023]
Abstract
A T cell receptor (TCR) mediates antigen-induced signaling through its associated CD3ε, δ, γ, and ζ, but the contributions of different CD3 chains remain elusive. Using quantitative mass spectrometry, we simultaneously quantitated the phosphorylation of the immunoreceptor tyrosine-based activation motif (ITAM) of all CD3 chains upon TCR stimulation. A subpopulation of CD3ε ITAMs was mono-phosphorylated, owing to Lck kinase selectivity, and specifically recruited the inhibitory Csk kinase to attenuate TCR signaling, suggesting that TCR is a self-restrained signaling machinery containing both activating and inhibitory motifs. Moreover, we found that incorporation of the CD3ε cytoplasmic domain into a second-generation chimeric antigen receptor (CAR) improved antitumor activity of CAR-T cells. Mechanistically, the Csk-recruiting ITAM of CD3ε reduced CAR-T cytokine production whereas the basic residue rich sequence (BRS) of CD3ε promoted CAR-T persistence via p85 recruitment. Collectively, CD3ε is a built-in multifunctional signal tuner, and increasing CD3 diversity represents a strategy to design next-generation CAR.
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Affiliation(s)
- Wei Wu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Qiuping Zhou
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Takeya Masubuchi
- Section of Cell & Developmental Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093-0347, USA
| | - Xiaoshan Shi
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China; Center for Precision Medicine Multi-omics Research, Peking University Health Science Center, Peking University First Hospital, Beijing 100191, China
| | - Hua Li
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Xinyi Xu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Min Huang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Li Meng
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Xing He
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Hengyu Zhu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Shuaixin Gao
- Center for Precision Medicine Multi-omics Research, Peking University Health Science Center, Peking University First Hospital, Beijing 100191, China
| | - Nan Zhang
- Center for Precision Medicine Multi-omics Research, Peking University Health Science Center, Peking University First Hospital, Beijing 100191, China
| | - Ruirui Jing
- Bone Marrow Transplantation Center of the First Affiliated Hospital and Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou 310058, Zhejiang, China; Institute of Hematology, Zhejiang University & Laboratory of Stem Cell and Immunotherapy Engineering, Hangzhou 310058, Zhejiang, China
| | - Jie Sun
- Bone Marrow Transplantation Center of the First Affiliated Hospital and Department of Cell Biology, Zhejiang University School of Medicine, Hangzhou 310058, Zhejiang, China; Institute of Hematology, Zhejiang University & Laboratory of Stem Cell and Immunotherapy Engineering, Hangzhou 310058, Zhejiang, China
| | - Haopeng Wang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Enfu Hui
- Section of Cell & Developmental Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093-0347, USA.
| | - Catherine Chiulan Wong
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China; Center for Precision Medicine Multi-omics Research, Peking University Health Science Center, Peking University First Hospital, Beijing 100191, China; School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China.
| | - Chenqi Xu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China; School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, Zhejiang, China.
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22
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Machine learning for cluster analysis of localization microscopy data. Nat Commun 2020; 11:1493. [PMID: 32198352 PMCID: PMC7083906 DOI: 10.1038/s41467-020-15293-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 02/27/2020] [Indexed: 12/29/2022] Open
Abstract
Quantifying the extent to which points are clustered in single-molecule localization microscopy data is vital to understanding the spatial relationships between molecules in the underlying sample. Many existing computational approaches are limited in their ability to process large-scale data sets, to deal effectively with sample heterogeneity, or require subjective user-defined analysis parameters. Here, we develop a supervised machine-learning approach to cluster analysis which is fast and accurate. Trained on a variety of simulated clustered data, the neural network can classify millions of points from a typical single-molecule localization microscopy data set, with the potential to include additional classifiers to describe different subtypes of clusters. The output can be further refined for the measurement of cluster area, shape, and point-density. We demonstrate this approach on simulated data and experimental data of the kinase Csk and the adaptor PAG in primary human T cell immunological synapses. The characterization of clusters in single-molecule microscopy data is vital to reconstruct emerging spatial patterns. Here, the authors present a fast and accurate machine-learning approach to clustering, to address the issues related to the size of the data and to sample heterogeneity.
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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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Voisinne G, Gonzalez de Peredo A, Roncagalli R. CD5, an Undercover Regulator of TCR Signaling. Front Immunol 2018; 9:2900. [PMID: 30581443 PMCID: PMC6292949 DOI: 10.3389/fimmu.2018.02900] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 11/26/2018] [Indexed: 11/28/2022] Open
Abstract
T cells are critical components of adaptive immunity. As such, their activation is regulated by the T cell receptor (TCR) that constantly scan peptides associated with major histocompatibility complexes (MHC). TCR engagement initiates a series of molecular events leading to cytokine secretion, proliferation, and differentiation of T cells. As a second coincident event, activation of co-stimulatory molecules, such as CD28, synergize with the TCR in order to prolong and/or amplify intracellular signals. With the recent advances in immunotherapies targeting T cells, co-inhibitory receptors are of growing interest for immunologists due to their potential modulatory properties on T cell functions. However, special attention should be dedicated to avoid unwanted clinical outcomes (1). In particular, Manichean categorization of receptors based on incomplete functional knowledge can lead to an over-simplistic view of complex cellular regulations. Thus, analysis of the functions that characterize these receptors in diverse physiological contexts remains essential for their rational use in therapeutic protocols. Here we focus on CD5, a transmembrane receptor that regulates T cell functions and development but remains poorly characterized at the molecular level. We will review its roles in physiological conditions and suggest potential molecular effectors that could account for CD5-dependent regulation of TCR signaling.
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Affiliation(s)
- Guillaume Voisinne
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, INSERM, CNRS, Marseille, France
| | - Anne Gonzalez de Peredo
- Institut de Pharmacologie et de Biologie Structurale, Département Biologie Structural Biophysique, Protéomique Génopole Toulouse Midi Pyrénées CNRS UMR 5089, Toulouse, France
| | - Romain Roncagalli
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, INSERM, CNRS, Marseille, France
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25
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Genome-wide CRISPR screen identifies FAM49B as a key regulator of actin dynamics and T cell activation. Proc Natl Acad Sci U S A 2018; 115:E4051-E4060. [PMID: 29632189 DOI: 10.1073/pnas.1801340115] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Despite decades of research, mechanisms controlling T cell activation remain only partially understood, which hampers T cell-based immune cancer therapies. Here, we performed a genome-wide CRISPR screen to search for genes that regulate T cell activation. Our screen confirmed many of the known regulators in proximal T cell receptor signaling and, importantly, also uncovered a previously uncharacterized regulator, FAM49B (family with sequence similarity 49 member B). FAM49B deficiency led to hyperactivation of Jurkat T cells following T cell receptor stimulation, as indicated by enhancement of CD69 induction, PAK phosphorylation, and actin assembly. FAM49B directly interacted with the active form of the small GTPase Rac, and genetic disruption of the FAM49B-Rac interaction compromised FAM49B function. Thus, FAM49B inhibits T cell activation by repressing Rac activity and modulating cytoskeleton reorganization.
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26
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CD45 in human physiology and clinical medicine. Immunol Lett 2018; 196:22-32. [PMID: 29366662 DOI: 10.1016/j.imlet.2018.01.009] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 01/18/2018] [Accepted: 01/19/2018] [Indexed: 01/20/2023]
Abstract
CD45 is an evolutionary highly conserved receptor protein tyrosine phosphatase exclusively expressed on all nucleated cells of the hematopoietic system. It is characterized by the expression of several isoforms, specific to a certain cell type and the developmental or activation status of the cell. CD45 is one of the key players in the initiation of T cell receptor signaling by controlling the activation of the Src family protein-tyrosine kinases Lck and Fyn. CD45 deficiency results in T- and B-lymphocyte dysfunction in the form of severe combined immune deficiency. It also plays a significant role in autoimmune diseases and cancer as well as in infectious diseases including fungal infections. The knowledge collected on CD45 biology is rather vast, but it remains unclear whether all findings in rodent immune cells also apply to human CD45. This review focuses on human CD45 expression and function and provides an overview on its ligands and role in human pathology.
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27
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Davidson D, Zhong MC, Pandolfi PP, Bolland S, Xavier RJ, Seed B, Li X, Gu H, Veillette A. The Csk-Associated Adaptor PAG Inhibits Effector T Cell Activation in Cooperation with Phosphatase PTPN22 and Dok Adaptors. Cell Rep 2017; 17:2776-2788. [PMID: 27926878 DOI: 10.1016/j.celrep.2016.11.035] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/19/2016] [Accepted: 11/10/2016] [Indexed: 10/20/2022] Open
Abstract
The transmembrane adaptor PAG (Cbp) has been proposed to mediate membrane recruitment of Csk, a cytoplasmic protein tyrosine kinase playing a critical inhibitory role during T cell activation, by inactivating membrane-associated Src kinases. However, this model has not been validated by genetic evidence. Here, we demonstrate that PAG-deficient mice display enhanced T cell activation responses in effector, but not in naive, T cells. PAG-deficient mice also have augmented T cell-dependent autoimmunity and greater resistance to T cell anergy. Interestingly, in the absence of PAG, Csk becomes more associated with alternative partners; i.e., phosphatase PTPN22 and Dok adaptors. Combining PAG deficiency with PTPN22 or Dok adaptor deficiency further enhances effector T cell responses. Unlike PAG, Cbl ubiquitin ligases inhibit the activation of naive, but not of effector, T cells. Thus, Csk-associating PAG is a critical component of the inhibitory machinery controlling effector T cell activation in cooperation with PTPN22 and Dok adaptors.
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Affiliation(s)
- Dominique Davidson
- Laboratory of Molecular Oncology, Institut de recherches cliniques de Montréal, Montréal, QC H2W 1R7, Canada.
| | - Ming-Chao Zhong
- Laboratory of Molecular Oncology, Institut de recherches cliniques de Montréal, Montréal, QC H2W 1R7, Canada
| | - Pier Paolo Pandolfi
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, Boston, MA 02215, USA
| | - Silvia Bolland
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD 20852, USA
| | - Ramnik J Xavier
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Brian Seed
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Xin Li
- Laboratory of Molecular Immunology, Institut de recherches cliniques de Montréal, Montréal, QC H2W 1R7, Canada
| | - Hua Gu
- Laboratory of Molecular Immunology, Institut de recherches cliniques de Montréal, Montréal, QC H2W 1R7, Canada; Department of Medicine, University of Montréal, Montréal, QC H3C 3J7, Canada; Department of Medicine, McGill University, Montréal, QC H3G 1Y6, Canada
| | - André Veillette
- Laboratory of Molecular Oncology, Institut de recherches cliniques de Montréal, Montréal, QC H2W 1R7, Canada; Department of Medicine, University of Montréal, Montréal, QC H3C 3J7, Canada; Department of Medicine, McGill University, Montréal, QC H3G 1Y6, Canada.
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28
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Blas-Rus N, Bustos-Morán E, Martín-Cófreces NB, Sánchez-Madrid F. Aurora-A shines on T cell activation through the regulation of Lck. Bioessays 2016; 39. [PMID: 27910998 DOI: 10.1002/bies.201600156] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Different protein kinases control signaling emanating from the T cell receptor (TCR) during antigen-specific T cell activation. Mitotic kinases, e.g. Aurora-A, have been widely studied in the context of mitosis due to their role during microtubule (MT) nucleation, becoming critical regulators of cell cycle progression. We have recently described a specific role for Aurora-A kinase in antigenic T cell activation. Blockade of Aurora-A in T cells severely disrupts the dynamics of MTs and CD3ζ-bearing signaling vesicles during T cell activation. Furthermore, Aurora-A deletion impairs the activation of signaling molecules downstream of the TCR. Targeting Aurora-A disturbs the activation of Lck, which is one of the first signals that drive T cell activation in an antigen-dependent manner. This work describes possible models of regulation of Lck by Aurora-A during T cell activation. We also discuss possible roles for Aurora-A in other systems similar to the IS, and its putative functions in cell polarization.
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Affiliation(s)
- Noelia Blas-Rus
- Servicio de Inmunología, Hospital Universitario de la Princesa, Instituto Investigación Sanitaria Princesa (IIS-IP), Universidad Autónoma de Madrid, Madrid, Spain
| | - Eugenio Bustos-Morán
- Vascular Pathophysiology Area, Centro Nacional Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Noa B Martín-Cófreces
- Vascular Pathophysiology Area, Centro Nacional Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Francisco Sánchez-Madrid
- Servicio de Inmunología, Hospital Universitario de la Princesa, Instituto Investigación Sanitaria Princesa (IIS-IP), Universidad Autónoma de Madrid, Madrid, Spain.,Vascular Pathophysiology Area, Centro Nacional Investigaciones Cardiovasculares (CNIC), Madrid, Spain
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29
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Cai LL, Liu GY, Tzeng CM. Genome-wide DNA methylation profiling and its involved molecular pathways from one individual with thyroid malignant/benign tumor and hyperplasia: A case report. Medicine (Baltimore) 2016; 95:e4695. [PMID: 27583899 PMCID: PMC5008583 DOI: 10.1097/md.0000000000004695] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND During development, methylation permanently changes gene activity, while aberrant gene methylation is key to human tumorigenesis. Gene methylation is an epigenetic event leading to gene silencing and some tumor suppressor genes that are aberrantly methylated in both thyroid cancer and benign thyroid tumor, suggesting a role for methylation in early thyroid tumorigenesis. Specific gene methylation occurs in certain types of thyroid cancer and depends on particular signaling pathways. Most reports rely on data from varied samples that vary tremendously with respect to methylation. RESULTS We observed that hyperplastic/malignant (H/M) thyroid tissue and benign/manligant (B/M) tissue had the most profoundly methylated loci compared to hyperplastic/benign (H/B) tissue. These loci are mapped to 863 genes (|Δβ value| > 0.15) in B/M and 1082 genes (|Δβ value| > 0.15) in H/M. After bioinformatic analysis, these genes were found to be involved in T-cell receptor signaling pathway (B/M) and Jak-Stat signaling pathways (H/M). CONCLUSION Our study offers the most comprehensive DNA methylation data for thyroid disease to date, using 1 patient with 3 tissue types and high-resolution 450K arrays. Our data may lay the foundation for future identification of novel epigenetic targets or diagnosis of thyroid cancer.
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Affiliation(s)
- Liang-Liang Cai
- Translational Medicine Research Center, School of Pharmaceutical Sciences
| | - Guo-Yan Liu
- Department of Gastrointestinal Surgery, Zhongshan Hospital, Xiamen University
| | - Chi-Meng Tzeng
- Translational Medicine Research Center, School of Pharmaceutical Sciences
- Key Laboratory for Cancer T-Cell Theranostics and Clinical Translation
- INNOVA Cell: TDx Clinics and TRANSLATE Health Group, Xiamen University, China
- Correspondence: Chi-Meng Tzeng, School of Pharmaceutical Sciences, Xiamen University, China (e-mail: )
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30
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Voisinne G, García-Blesa A, Chaoui K, Fiore F, Bergot E, Girard L, Malissen M, Burlet-Schiltz O, Gonzalez de Peredo A, Malissen B, Roncagalli R. Co-recruitment analysis of the CBL and CBLB signalosomes in primary T cells identifies CD5 as a key regulator of TCR-induced ubiquitylation. Mol Syst Biol 2016; 12:876. [PMID: 27474268 PMCID: PMC4965873 DOI: 10.15252/msb.20166837] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
T-cell receptor (TCR) signaling is essential for the function of T cells and negatively regulated by the E3 ubiquitin-protein ligases CBL and CBLB Here, we combined mouse genetics and affinity purification coupled to quantitative mass spectrometry to monitor the dynamics of the CBL and CBLB signaling complexes that assemble in normal T cells over 600 seconds of TCR stimulation. We identify most previously known CBL and CBLB interacting partners, as well as a majority of proteins that have not yet been implicated in those signaling complexes. We exploit correlations in protein association with CBL and CBLB as a function of time of TCR stimulation for predicting the occurrence of direct physical association between them. By combining co-recruitment analysis with biochemical analysis, we demonstrated that the CD5 transmembrane receptor constitutes a key scaffold for CBL- and CBLB-mediated ubiquitylation following TCR engagement. Our results offer an integrated view of the CBL and CBLB signaling complexes induced by TCR stimulation and provide a molecular basis for their negative regulatory function in normal T cells.
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Affiliation(s)
- Guillaume Voisinne
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, Marseille, France
| | - Antonio García-Blesa
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, Marseille, France
| | - Karima Chaoui
- Institut de Pharmacologie et de Biologie Structurale, Département Biologie Structural Biophysique, Protéomique Génopole Toulouse Midi Pyrénées, CNRS UMR 5089, Toulouse Cedex, France
| | - Frédéric Fiore
- Centre d'Immunophénomique, Aix Marseille Université UM2, Inserm US012, CNRS UMS3367, Marseille, France
| | - Elise Bergot
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, Marseille, France
| | - Laura Girard
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, Marseille, France Centre d'Immunophénomique, Aix Marseille Université UM2, Inserm US012, CNRS UMS3367, Marseille, France
| | - Marie Malissen
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, Marseille, France Centre d'Immunophénomique, Aix Marseille Université UM2, Inserm US012, CNRS UMS3367, Marseille, France
| | - Odile Burlet-Schiltz
- Institut de Pharmacologie et de Biologie Structurale, Département Biologie Structural Biophysique, Protéomique Génopole Toulouse Midi Pyrénées, CNRS UMR 5089, Toulouse Cedex, France
| | - Anne Gonzalez de Peredo
- Institut de Pharmacologie et de Biologie Structurale, Département Biologie Structural Biophysique, Protéomique Génopole Toulouse Midi Pyrénées, CNRS UMR 5089, Toulouse Cedex, France
| | - Bernard Malissen
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, Marseille, France Centre d'Immunophénomique, Aix Marseille Université UM2, Inserm US012, CNRS UMS3367, Marseille, France
| | - Romain Roncagalli
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Inserm, CNRS, Marseille, France
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31
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Wehbi VL, Taskén K. Molecular Mechanisms for cAMP-Mediated Immunoregulation in T cells - Role of Anchored Protein Kinase A Signaling Units. Front Immunol 2016; 7:222. [PMID: 27375620 PMCID: PMC4896925 DOI: 10.3389/fimmu.2016.00222] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 05/23/2016] [Indexed: 12/20/2022] Open
Abstract
The cyclic AMP/protein kinase A (cAMP/PKA) pathway is one of the most common and versatile signal pathways in eukaryotic cells. A-kinase anchoring proteins (AKAPs) target PKA to specific substrates and distinct subcellular compartments providing spatial and temporal specificity for mediation of biological effects channeled through the cAMP/PKA pathway. In the immune system, cAMP is a potent negative regulator of T cell receptor-mediated activation of effector T cells (Teff) acting through a proximal PKA/Csk/Lck pathway anchored via a scaffold consisting of the AKAP Ezrin holding PKA, the linker protein EBP50, and the anchoring protein phosphoprotein associated with glycosphingolipid-enriched microdomains holding Csk. As PKA activates Csk and Csk inhibits Lck, this pathway in response to cAMP shuts down proximal T cell activation. This immunomodulating pathway in Teff mediates clinically important responses to regulatory T cell (Treg) suppression and inflammatory mediators, such as prostaglandins (PGs), adrenergic stimuli, adenosine, and a number of other ligands. A major inducer of T cell cAMP levels is PG E2 (PGE2) acting through EP2 and EP4 prostanoid receptors. PGE2 plays a crucial role in the normal physiological control of immune homeostasis as well as in inflammation and cancer immune evasion. Peripherally induced Tregs express cyclooxygenase-2, secrete PGE2, and elicit the immunosuppressive cAMP pathway in Teff as one tumor immune evasion mechanism. Moreover, a cAMP increase can also be induced by indirect mechanisms, such as intercellular transfer between T cells. Indeed, Treg, known to have elevated levels of intracellular cAMP, may mediate their suppressive function by transferring cAMP to Teff through gap junctions, which we speculate could also be regulated by PKA/AKAP complexes. In this review, we present an updated overview on the influence of cAMP-mediated immunoregulatory mechanisms acting through localized cAMP signaling and the therapeutical increasing prospects of AKAPs disruptors in T-cell immune function.
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Affiliation(s)
- Vanessa L. Wehbi
- Nordic EMBL Partnership, Centre for Molecular Medicine Norway, Oslo University Hospital, University of Oslo, Oslo, Norway
- Jebsen Inflammation Research Centre, Oslo University Hospital, Oslo, Norway
- Biotechnology Centre, Oslo University Hospital, University of Oslo, Oslo, Norway
| | - Kjetil Taskén
- Nordic EMBL Partnership, Centre for Molecular Medicine Norway, Oslo University Hospital, University of Oslo, Oslo, Norway
- Jebsen Inflammation Research Centre, Oslo University Hospital, Oslo, Norway
- Biotechnology Centre, Oslo University Hospital, University of Oslo, Oslo, Norway
- Jebsen Centre for Cancer Immunotherapy, Oslo University Hospital, Oslo, Norway
- Department of Infectious Diseases, Oslo University Hospital, Oslo, Norway
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32
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Manz BN, Tan YX, Courtney AH, Rutaganira F, Palmer E, Shokat KM, Weiss A. Small molecule inhibition of Csk alters affinity recognition by T cells. eLife 2015; 4. [PMID: 26302204 PMCID: PMC4568592 DOI: 10.7554/elife.08088] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 08/22/2015] [Indexed: 12/12/2022] Open
Abstract
The C-terminal Src kinase (Csk), the primary negative regulator of Src-family kinases (SFK), plays a crucial role in controlling basal and inducible receptor signaling. To investigate how Csk activity regulates T cell antigen receptor (TCR) signaling, we utilized a mouse expressing mutated Csk (CskAS) whose catalytic activity is specifically and rapidly inhibited by a small molecule. Inhibition of CskAS during TCR stimulation led to stronger and more prolonged TCR signaling and to increased proliferation. Inhibition of CskAS enhanced activation by weak but strictly cognate agonists. Titration of Csk inhibition revealed that a very small increase in SFK activity was sufficient to potentiate T cell responses to weak agonists. Csk plays an important role, not only in basal signaling, but also in setting the TCR signaling threshold and affinity recognition. DOI:http://dx.doi.org/10.7554/eLife.08088.001 The immune system has ‘T’ cells that recognize when the body is infected with a virus or bacterium and mount an immune response that is targeted to that microbe. They can also find and eliminate cancer cells. The microbes and cancer cells produce molecules called antigens that are detected by proteins on the surface of the T cell called T cell receptors (TCR). Antigen recognition causes the TCRs to transmit signals to the inside of the T cell that trigger an immune response. The degree to which the TCRs are active, and the length of time that they transmit signals regulates the size of the immune response. Therefore, developing new drugs that manipulate the activity of TCRs could be useful to treat many diseases. An enzyme called Csk inhibits the activities of a small family of proteins involved in a variety of different processes. One protein that Csk targets is called Lck and is required for the activation of immune responses in T cells. However, it is not clear whether Csk interacting with this protein stops the release of signals from TCRs, or whether it alters the level to which TCRs need to be activated before they transmit the signals. Manz, Tan et al. studied T cells from mice that had a mutant form of Csk that is inhibited by a drug called 3-iodo-benzyl-PP1 (3-IB-PP1), but otherwise works normally. When these cells detected an antigen in the presence of the drug, its TCRs were more highly activated and transmitted signals for a longer period of time than cells not exposed to the drug. The drug especially enhanced immune responses to very weak antigens, ones that might not activate T cells under normal circumstances. Manz, Tan et al.'s findings confirm that Csk plays a negative role in the activation of T cells and suggest that Csk may be a useful target for drug therapies that aim to fine-tune immune responses. The next challenge is to find a drug that can inhibit normal Csk enzymes and test this in mice and other animals. DOI:http://dx.doi.org/10.7554/eLife.08088.002
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Affiliation(s)
- Boryana N Manz
- Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, United States
| | - Ying Xim Tan
- Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, United States
| | - Adam H Courtney
- Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, United States
| | - Florentine Rutaganira
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, United States
| | - Ed Palmer
- Departments of Biomedicine and Nephrology, University Hospital Basel, University of basel, Basel, Switzerland
| | - Kevan M Shokat
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, United States
| | - Arthur Weiss
- Rosalind Russell and Ephraim P. Engleman Rheumatology Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, United States
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33
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Vicente C, Edwards S, Hillman K, Kaufmann S, Mitchell H, Bain L, Glubb D, Lee J, French J, Ferreira M. Long-Range Modulation of PAG1 Expression by 8q21 Allergy Risk Variants. Am J Hum Genet 2015. [PMID: 26211970 DOI: 10.1016/j.ajhg.2015.06.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The gene(s) whose expression is regulated by allergy risk variants is unknown for many loci identified through genome-wide association studies. Addressing this knowledge gap might point to new therapeutic targets for allergic disease. The aim of this study was to identify the target gene(s) and the functional variant(s) underlying the association between rs7009110 on chromosome 8q21 and allergies. Eight genes are located within 1 Mb of rs7009110. Multivariate association analysis of publicly available exon expression levels from lymphoblastoid cell lines (LCLs) identified a significant association between rs7009110 and the expression of a single gene, PAG1 (p = 0.0017), 732 kb away. Analysis of histone modifications and DNase I hypersensitive sites in LCLs identified four putative regulatory elements (PREs) in the region. Chromosome conformation capture confirmed that two PREs interacted with the PAG1 promoter, one in allele-specific fashion. To determine whether these PREs were functional, LCLs were transfected with PAG1 promoter-driven luciferase reporter constructs. PRE3 acted as a transcriptional enhancer for PAG1 exclusively when it carried the rs2370615:C allergy predisposing allele, a variant in complete linkage disequilibrium with rs7009110. As such, rs2370615, which overlaps RelA transcription factor (TF) binding in LCLs and was found to disrupt Foxo3a binding to PRE3, represents the putative functional variant in this locus. Our studies suggest that the risk-associated allele of rs2370615 predisposes to allergic disease by increasing PAG1 expression, which might promote B cell activation and have a pro-inflammatory effect. Inhibition of PAG1 expression or function might have therapeutic potential for allergic diseases.
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Spleen-specific isoforms of Pax5 and Ataxin-7 as potential proteomic markers of lymphoma-affected spleen. Mol Cell Biochem 2015; 402:181-91. [PMID: 25573326 DOI: 10.1007/s11010-014-2325-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 12/23/2014] [Indexed: 02/06/2023]
Abstract
The splenomegaly, enlargement of spleen, has been observed in several diseases. It has been intended to evaluate histochemical alterations, spleen-specific enzymatic and proteomic markers during splenomegaly, and lympho-proliferative disorders from spleen of mice bearing Dalton's lymphoma. The higher expression of c-fos, c-jun, and MAPK testifies proliferation of lymphocytes. The lower expression of Pax5, higher expression of CD3, and the presence of additional form of Zap-70 suggest hypertrophy of follicles and splenomegaly influenced by weak B-cell receptor-mediated signaling, but activated T-cell receptor-mediated signaling. Simultaneously, lower levels of SOD, NDR2, and MIB2 and higher expression levels of Ataxin-7 and LDH also suggest impact of stress either as a cause or effect of cell proliferation. Spleen-specific isoform of Pax5, NDR2, MIB2, and Ataxin-7 can be considered as spleen-specific unique molecular markers for the evaluation of splenomegaly and lympho-proliferative disorders.
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Ji Q, Ding Y, Salomon AR. SRC homology 2 domain-containing leukocyte phosphoprotein of 76 kDa (SLP-76) N-terminal tyrosine residues regulate a dynamic signaling equilibrium involving feedback of proximal T-cell receptor (TCR) signaling. Mol Cell Proteomics 2014; 14:30-40. [PMID: 25316710 DOI: 10.1074/mcp.m114.037861] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
SRC homology 2 domain-containing leukocyte phosphoprotein of 76 kDa (SLP-76) is a cytosolic adaptor protein that plays an important role in the T-cell receptor-mediated T-cell signaling pathway. SLP-76 links proximal receptor stimulation to downstream effectors through interaction with many signaling proteins. Previous studies showed that mutation of three tyrosine residues, Tyr(112), Tyr(128), and Tyr(145), in the N terminus of SLP-76 results in severely impaired phosphorylation and activation of Itk and PLCγ1, which leads to defective calcium mobilization, Erk activation, and NFAT activation. To expand our knowledge of the role of N-terminal phosphorylation of SLP-76 from these three tyrosine sites, we characterized nearly 1000 tyrosine phosphorylation sites via mass spectrometry in SLP-76 reconstituted wild-type cells and SLP-76 mutant cells in which three tyrosine residues were replaced with phenylalanines (Y3F mutant). Mutation of the three N-terminal tyrosine residues of SLP-76 phenocopied SLP-76-deficient cells for the majority of tyrosine phosphorylation sites observed, including feedback on proximal T-cell receptor signaling proteins. Meanwhile, reversed phosphorylation changes were observed on Tyr(192) of Lck when we compared mutants to the complete removal of SLP-76. In addition, N-terminal tyrosine sites of SLP-76 also perturbed phosphorylation of Tyr(440) of Fyn, Tyr(702) of PLCγ1, Tyr(204), Tyr(397), and Tyr(69) of ZAP-70, revealing new modes of regulation on these sites. All these findings confirmed the central role of N-terminal tyrosine sites of SLP-76 in the pathway and also shed light on novel signaling events that are uniquely regulated by SLP-76 N-terminal tyrosine residues.
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Affiliation(s)
- Qinqin Ji
- From the ‡Department of Chemistry, Brown University Providence, RI 02903
| | - Yiyuan Ding
- From the ‡Department of Chemistry, Brown University Providence, RI 02903
| | - Arthur R Salomon
- From the ‡Department of Chemistry, Brown University Providence, RI 02903; §Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University Providence, RI 02903
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Affiliation(s)
- Michael L Dustin
- Kennedy Institute of Rheumatology and Nuffield Department of Orthopedics and Musculoskeletal Sciences, The University of Oxford, Oxford, UK
| | - Simon J Davis
- Medical Research Council Human Immunology Unit and Radcliffe Department of Clinical Medicine, Weatherall Institute of Molecular Medicine, The University of Oxford, Oxford, UK
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Tan YX, Manz BN, Freedman TS, Zhang C, Shokat KM, Weiss A. Inhibition of the kinase Csk in thymocytes reveals a requirement for actin remodeling in the initiation of full TCR signaling. Nat Immunol 2014; 15:186-94. [PMID: 24317039 PMCID: PMC3946925 DOI: 10.1038/ni.2772] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 10/23/2013] [Indexed: 12/15/2022]
Abstract
Signaling via the T cell antigen receptor (TCR) is initiated by Src-family kinases (SFKs). To understand how the kinase Csk, a negative regulator of SFKs, controls the basal state and the initiation of TCR signaling, we generated mice that express a Csk variant sensitive to an analog of the common kinase inhibitor PP1 (Csk(AS)). Inhibition of Csk(AS) in thymocytes, without engagement of the TCR, induced potent activation of SFKs and proximal TCR signaling up to phospholipase C-γ1 (PLC-γ1). Unexpectedly, increases in inositol phosphates, intracellular calcium and phosphorylation of the kinase Erk were impaired. Altering the actin cytoskeleton pharmacologically or providing costimulation via CD28 'rescued' those defects. Thus, Csk has a critical role in preventing TCR signaling. However, our studies also revealed a requirement for actin remodeling, initiated by costimulation, for full TCR signaling.
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Affiliation(s)
- Ying Xim Tan
- Rosalind Russell-Ephraim P. Engleman Medical Research Center for Arthritis, Division of Rheumatology, Department of Medicine, University of California, San Francisco, California, USA
| | - Boryana N Manz
- Rosalind Russell-Ephraim P. Engleman Medical Research Center for Arthritis, Division of Rheumatology, Department of Medicine, University of California, San Francisco, California, USA
| | - Tanya S Freedman
- Rosalind Russell-Ephraim P. Engleman Medical Research Center for Arthritis, Division of Rheumatology, Department of Medicine, University of California, San Francisco, California, USA
| | - Chao Zhang
- Department of Chemistry, University of Southern California, California, USA
| | - Kevan M Shokat
- 1] Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California, USA. [2] Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
| | - Arthur Weiss
- 1] Rosalind Russell-Ephraim P. Engleman Medical Research Center for Arthritis, Division of Rheumatology, Department of Medicine, University of California, San Francisco, California, USA. [2] Howard Hughes Medical Institute, Chevy Chase, Maryland, USA. [3] Department of Microbiology and Immunology, University of California, San Francisco, California, USA
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CKIP-1 is an intrinsic negative regulator of T-cell activation through an interaction with CARMA1. PLoS One 2014; 9:e85762. [PMID: 24465689 PMCID: PMC3894987 DOI: 10.1371/journal.pone.0085762] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 12/05/2013] [Indexed: 11/19/2022] Open
Abstract
The transcription factor NF-κB plays a key regulatory role in lymphocyte activation and generation of immune response. Stimulation of T cell receptor (TCR) induces phosphorylation of CARMA1 by PKCθ, resulting in formation of CARMA1-Bcl10-MALT1 (CBM) complex at lipid rafts and subsequently leading to NF-κB activation. While many molecular events leading to NF-κB activation have been reported, it is less understood how this activation is negatively regulated. We performed a cell-based screening for negative regulators of TCR-mediated NF-κB activation, using mutagenesis and complementation cloning strategies. Here we show that casein kinase-2 interacting protein-1 (CKIP-1) suppresses PKCθ-CBM-NF-κB signaling. We found that CKIP-1 interacts with CARMA1 and competes with PKCθ for association. We further confirmed that a PH domain of CKIP-1 is required for association with CARMA1 and its inhibitory effect. CKIP-1 represses NF-κB activity in unstimulated cells, and inhibits NF-κB activation induced by stimulation with PMA or constitutively active PKCθ, but not by stimulation with TNFα. Interestingly, CKIP-1 does not inhibit NF-κB activation induced by CD3/CD28 costimulation, which caused dissociation of CKIP-1 from lipid rafts. These data suggest that CKIP-1 contributes maintenance of a resting state on NF-κB activity or prevents T cells from being activated by inadequate signaling. In conclusion, we demonstrate that CKIP-1 interacts with CARMA1 and has an inhibitory effect on PKCθ-CBM-NF-κB signaling.
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39
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Palmitoylated transmembrane adaptor proteins in leukocyte signaling. Cell Signal 2014; 26:895-902. [PMID: 24440308 DOI: 10.1016/j.cellsig.2014.01.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 01/07/2014] [Accepted: 01/09/2014] [Indexed: 12/14/2022]
Abstract
Transmembrane adaptor proteins (TRAPs) are structurally related proteins that have no enzymatic function, but enable inducible recruitment of effector molecules to the plasma membrane, usually in a phosphorylation dependent manner. Numerous surface receptors employ TRAPs for either propagation or negative regulation of the signal transduction. Several TRAPs (LAT, NTAL, PAG, LIME, PRR7, SCIMP, LST1/A, and putatively GAPT) are known to be palmitoylated that could facilitate their localization in lipid rafts or tetraspanin enriched microdomains. This review summarizes expression patterns, binding partners, signaling pathways, and biological functions of particular palmitoylated TRAPs with an emphasis on the three most recently discovered members, PRR7, SCIMP, and LST1/A. Moreover, we discuss in silico methodology used for discovery of new family members, nature of their binding partners, and microdomain localization.
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Le Page A, Fortin C, Garneau H, Allard N, Tsvetkova K, Tan CTY, Larbi A, Dupuis G, Fülöp T. Downregulation of inhibitory SRC homology 2 domain-containing phosphatase-1 (SHP-1) leads to recovery of T cell responses in elderly. Cell Commun Signal 2014; 12:2. [PMID: 24405902 PMCID: PMC3896791 DOI: 10.1186/1478-811x-12-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 01/04/2014] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Immune responses are generally impaired in aged mammals. T cells have been extensively studied in this context due to the initial discovery of their reduced proliferative capacity with aging. The decreased responses involve altered signaling events associated with the early steps of T cell activation. The underlying causes of these changes are not fully understood but point to alterations in assembly of the machinery for T cell activation. Here, we have tested the hypothesis that the T cell pool in elderly subjects displayed reduced functional capacities due to altered negative feedback mechanisms that participate in the regulation of the early steps of T cell activation. Such conditions tip the immune balance in favor of altered T cell activation and a related decreased response in aging. RESULTS We present evidence that the tyrosine phosphatase SHP-1, a key regulator of T cell signal transduction machinery is, at least in part, responsible for the impaired T cell activation in aging. We used tyrosine-specific mAbs and Western blot analysis to show that a deregulation of the Csk/PAG loop in activated T cells from elderly individuals favored the inactive form of tyrosine-phosphorylated Lck (Y505). Confocal microscopy analysis revealed that the dynamic movements of these regulatory proteins in lipid raft microdomains was altered in T cells of aged individuals. Enzymic assays showed that SHP-1 activity was upregulated in T cells of aged donors, in contrast to young subjects. Pharmacological inhibition of SHP-1 resulted in recovery of TCR/CD28-dependent lymphocyte proliferation and IL-2 production of aged individuals to levels approaching those of young donors. Significant differences in the active (Y394) and inactive (Y505) phosphorylation sites of Lck in response to T cell activation were observed in elderly donors as compared to young subjects, independently of CD45 isoform expression. CONCLUSIONS Our data suggest that the role of SHP-1 in T cell activation extends to its increased effect in negative feedback in aging. Modulation of SHP-1 activity could be a target to restore altered T cell functions in aging. These observations could have far reaching consequences for improvement of immunosenescence and its clinical consequences such as infections, altered response to vaccination.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Tamas Fülöp
- Research Center on Aging, Faculty of Medicine and Health Sciences, Université de Sherbrooke, 1036 rue Belvedere sud, Sherbrooke, J1H 4C4, Quebec, Canada.
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41
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Bottini N, Peterson EJ. Tyrosine phosphatase PTPN22: multifunctional regulator of immune signaling, development, and disease. Annu Rev Immunol 2013; 32:83-119. [PMID: 24364806 DOI: 10.1146/annurev-immunol-032713-120249] [Citation(s) in RCA: 146] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Inheritance of a coding variant of the protein tyrosine phosphatase nonreceptor type 22 (PTPN22) gene is associated with increased susceptibility to autoimmunity and infection. Efforts to elucidate the mechanisms by which the PTPN22-C1858T variant modulates disease risk revealed that PTPN22 performs a signaling function in multiple biochemical pathways and cell types. Capable of both enzymatic activity and adaptor functions, PTPN22 modulates signaling through antigen and innate immune receptors. PTPN22 plays roles in lymphocyte development and activation, establishment of tolerance, and innate immune cell-mediated host defense and immunoregulation. The disease-associated PTPN22-R620W variant protein is likely involved in multiple stages of the pathogenesis of autoimmunity. Establishment of a tolerant B cell repertoire is disrupted by PTPN22-R620W action during immature B cell selection, and PTPN22-R620W alters mature T cell responsiveness. However, after autoimmune attack has initiated tissue injury, PTPN22-R620W may foster inflammation through modulating the balance of myeloid cell-produced cytokines.
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Affiliation(s)
- Nunzio Bottini
- Division of Cellular Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California 92037;
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Chapman NM, Connolly SF, Reinl EL, Houtman JCD. Focal adhesion kinase negatively regulates Lck function downstream of the T cell antigen receptor. THE JOURNAL OF IMMUNOLOGY 2013; 191:6208-21. [PMID: 24227778 DOI: 10.4049/jimmunol.1301587] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Focal adhesion kinase (FAK) is a critical regulator of signal transduction in multiple cell types. Although this protein is activated upon TCR engagement, the cellular function that FAK plays in mature human T cells is unknown. By suppressing the function of FAK, we revealed that FAK inhibits TCR-mediated signaling by recruiting C-terminal Src kinase to the membrane and/or receptor complex following TCR activation. Thus, in the absence of FAK, the inhibitory phosphorylation of Lck and/or Fyn is impaired. Together, these data highlight a novel role for FAK as a negative regulator TCR function in human T cells. These results also suggest that changes in FAK expression could modulate sensitivity to TCR stimulation and contribute to the progression of T cell malignancies and autoimmune diseases.
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Affiliation(s)
- Nicole M Chapman
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242
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43
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Hrdinka M, Horejsi V. PAG - a multipurpose transmembrane adaptor protein. Oncogene 2013; 33:4881-92. [DOI: 10.1038/onc.2013.485] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/25/2013] [Accepted: 09/25/2013] [Indexed: 12/25/2022]
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Abstract
Tyrosine phosphorylation is one of the key covalent modifications that occur in multicellular organisms. Since its discovery more than 30 years ago, tyrosine phosphorylation has come to be understood as a fundamentally important mechanism of signal transduction and regulation in all eukaryotic cells. The tyrosine kinase Lck (lymphocyte-specific protein tyrosine kinase) plays a crucial role in the T-cell response by transducing early activation signals triggered by TCR (T-cell receptor) engagement. These signals result in the phosphorylation of immunoreceptor tyrosine-based activation motifs present within the cytosolic tails of the TCR-associated CD3 subunits that, once phosphorylated, serve as scaffolds for the assembly of a large supramolecular signalling complex responsible for T-cell activation. The existence of membrane nano- or micro-domains or rafts as specialized platforms for protein transport and cell signalling has been proposed. The present review discusses the signals that target Lck to membrane rafts and the importance of these specialized membranes in the transport of Lck to the plasma membrane, the regulation of Lck activity and the phosphorylation of the TCR.
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45
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Tan YX, Zikherman J, Weiss A. Novel tools to dissect the dynamic regulation of TCR signaling by the kinase Csk and the phosphatase CD45. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2013; 78:131-139. [PMID: 24100586 DOI: 10.1101/sqb.2013.78.020347] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Although the biochemical events induced by T-cell receptor (TCR) triggering have been well studied, both the mediators and function of basal signaling in T cells remain poorly understood. Furthermore, the precise mechanisms by which MHC-peptide interaction with the TCR disrupt the basal equilibrium to induce downstream signaling are also unclear. Here we describe novel approaches to understand the basal state of T cells and the mechanisms of TCR triggering by perturbing regulation of the Src family kinases (SFKs). The SFKs are critical proximal mediators of TCR signaling that are in turn tightly regulated by the tyrosine kinase Csk and the receptor-like tyrosine phosphatase CD45. We have developed a small-molecule analog-sensitive allele of Csk and an allelic series of mice in which expression of CD45 is varied across a broad range. Our studies have unmasked contributions of Csk and CD45 to maintain the basal state of T cells and also suggest that dynamic regulation of Csk may be involved in TCR triggering.
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Affiliation(s)
- Ying Xim Tan
- Division of Rheumatology, Rosalind Russell Medical Research Center for Arthritis, Department of Medicine, UCSF, San Francisco, CA, 94143, USA
| | - Julie Zikherman
- Division of Rheumatology, Rosalind Russell Medical Research Center for Arthritis, Department of Medicine, UCSF, San Francisco, CA, 94143, USA
| | - Arthur Weiss
- Division of Rheumatology, Rosalind Russell Medical Research Center for Arthritis, Department of Medicine, UCSF, San Francisco, CA, 94143, USA.,Howard Hughes Medical Institute, UCSF, San Francisco, CA, 94143, USA
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Brownlie RJ, Zamoyska R. T cell receptor signalling networks: branched, diversified and bounded. Nat Rev Immunol 2013; 13:257-69. [PMID: 23524462 DOI: 10.1038/nri3403] [Citation(s) in RCA: 333] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Engagement of antigen-specific T cell receptors (TCRs) is a prerequisite for T cell activation. Acquisition of appropriate effector T cell function requires the participation of multiple signals from the T cell microenvironment. Trying to understand how these signals integrate to achieve specific functional outcomes while maintaining tolerance to self is a major challenge in lymphocyte biology. Several recent publications have provided important insights into how dysregulation of T cell signalling and the development of autoreactivity can result if the branching and integration of signalling pathways are perturbed. We discuss how these findings highlight the importance of spatial segregation of individual signalling components as a way of regulating T cell responsiveness and immune tolerance.
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Affiliation(s)
- Rebecca J Brownlie
- Institute for Immunology and Infection Research, The University of Edinburgh, Edinburgh EH9 3JT, UK
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Smida M, Cammann C, Gurbiel S, Kerstin N, Lingel H, Lindquist S, Simeoni L, Brunner-Weinzierl MC, Suchanek M, Schraven B, Lindquist JA. PAG/Cbp suppression reveals a contribution of CTLA-4 to setting the activation threshold in T cells. Cell Commun Signal 2013; 11:28. [PMID: 23601194 PMCID: PMC3763844 DOI: 10.1186/1478-811x-11-28] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 04/03/2013] [Indexed: 11/12/2022] Open
Abstract
Background PAG/Cbp represents a ubiquitous mechanism for regulating Src family kinases
by recruiting Csk to the plasma membrane, thereby controlling cellular
activation. Since Src kinases are known oncogenes, we used RNA interference
in primary human T cells to test whether the loss of PAG resulted in
lymphocyte transformation. Results PAG-depletion enhanced Src kinase activity and augmented proximal T-cell
receptor signaling; exactly the phenotype expected for loss of this negative
regulator. Surprisingly, rather than becoming hyper-proliferative,
PAG-suppressed T cells became unresponsive. This was mediated by a
Fyn-dependent hyper-phosphorylation of the inhibitory receptor CTLA-4, which
recruited the protein tyrosine phosphatase Shp-1 to lipid rafts.
Co-suppression of CTLA-4 abrogates this inhibition and restores
proliferation to T cells. Conclusion We have identified a fail-safe mechanism as well as a novel contribution of
CTLA-4 to setting the activation threshold in T cells.
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Affiliation(s)
- Michal Smida
- Institute of Molecular and Clinical Immunology, Otto-von-Guericke University, Leipziger Strasse 44, Magdeburg, 39120, Germany.
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Borger JG, Filby A, Zamoyska R. Differential polarization of C-terminal Src kinase between naive and antigen-experienced CD8+ T cells. THE JOURNAL OF IMMUNOLOGY 2013; 190:3089-99. [PMID: 23427257 DOI: 10.4049/jimmunol.1202408] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In CD8(+) T cells, engagement of the TCR with agonist peptide:MHC molecules causes dynamic redistribution of surface molecules including the CD8 coreceptor to the immunological synapse. CD8 associates with the Src-family kinase (SFK) Lck, which, in turn, initiates the rapid tyrosine phosphorylation events that drive cellular activation. Compared with naive T cells, Ag-experienced CD8(+) T cells make shorter contacts with APC, are less dependent on costimulation, and are triggered by lower concentrations of Ag, yet the molecular basis of this more efficient response of memory T cells is not fully understood. In this article, we show differences between naive and Ag-experienced CD8(+) T cells in colocalization of the SFKs and their negative regulator, C-terminal Src kinase (Csk). In naive CD8(+) T cells, there was pronounced colocalization of SFKs and Csk at the site of TCR triggering, whereas in Ag-experienced cells, Csk displayed a bipolar distribution with a proportion of the molecules sequestered within a cytosolic area in the distal pole of the cell. The data show that there is differential redistribution of a key negative regulator away from the site of TCR engagement in Ag-experienced CD8(+) T cells, which might be associated with the more efficient responses of these cells on re-exposure to Ag.
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Affiliation(s)
- Jessica G Borger
- Institute of Immunology and Infection Research, The University of Edinburgh, Edinburgh EH9 3JT, United Kingdom
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Holmfeldt L, Wei L, Diaz-Flores E, Walsh M, Zhang J, Ding L, Payne-Turner D, Churchman M, Andersson A, Chen SC, McCastlain K, Becksfort J, Ma J, Wu G, Patel SN, Heatley SL, Phillips LA, Song G, Easton J, Parker M, Chen X, Rusch M, Boggs K, Vadodaria B, Hedlund E, Drenberg C, Baker S, Pei D, Cheng C, Huether R, Lu C, Fulton RS, Fulton LL, Tabib Y, Dooling DJ, Ochoa K, Minden M, Lewis ID, To LB, Marlton P, Roberts AW, Raca G, Stock W, Neale G, Drexler HG, Dickins RA, Ellison DW, Shurtleff SA, Pui CH, Ribeiro RC, Devidas M, Carroll AJ, Heerema NA, Wood B, Borowitz MJ, Gastier-Foster JM, Raimondi SC, Mardis ER, Wilson RK, Downing JR, Hunger SP, Loh ML, Mullighan CG. The genomic landscape of hypodiploid acute lymphoblastic leukemia. Nat Genet 2013; 45:242-52. [PMID: 23334668 DOI: 10.1038/ng.2532] [Citation(s) in RCA: 489] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 12/21/2012] [Indexed: 12/17/2022]
Abstract
The genetic basis of hypodiploid acute lymphoblastic leukemia (ALL), a subtype of ALL characterized by aneuploidy and poor outcome, is unknown. Genomic profiling of 124 hypodiploid ALL cases, including whole-genome and exome sequencing of 40 cases, identified two subtypes that differ in the severity of aneuploidy, transcriptional profiles and submicroscopic genetic alterations. Near-haploid ALL with 24-31 chromosomes harbor alterations targeting receptor tyrosine kinase signaling and Ras signaling (71%) and the lymphoid transcription factor gene IKZF3 (encoding AIOLOS; 13%). In contrast, low-hypodiploid ALL with 32-39 chromosomes are characterized by alterations in TP53 (91.2%) that are commonly present in nontumor cells, IKZF2 (encoding HELIOS; 53%) and RB1 (41%). Both near-haploid and low-hypodiploid leukemic cells show activation of Ras-signaling and phosphoinositide 3-kinase (PI3K)-signaling pathways and are sensitive to PI3K inhibitors, indicating that these drugs should be explored as a new therapeutic strategy for this aggressive form of leukemia.
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Affiliation(s)
- Linda Holmfeldt
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
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Cao L, Ding Y, Hung N, Yu K, Ritz A, Raphael BJ, Salomon AR. Quantitative phosphoproteomics reveals SLP-76 dependent regulation of PAG and Src family kinases in T cells. PLoS One 2012; 7:e46725. [PMID: 23071622 PMCID: PMC3469622 DOI: 10.1371/journal.pone.0046725] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 09/07/2012] [Indexed: 12/14/2022] Open
Abstract
The SH2-domain-containing leukocyte protein of 76 kDa (SLP-76) plays a critical scaffolding role in T cell receptor (TCR) signaling. As an adaptor protein that contains multiple protein-binding domains, SLP-76 interacts with many signaling molecules and links proximal receptor stimulation to downstream effectors. The function of SLP-76 in TCR signaling has been widely studied using the Jurkat human leukaemic T cell line through protein disruption or site-directed mutagenesis. However, a wide-scale characterization of SLP-76-dependant phosphorylation events is still lacking. Quantitative profiling of over a hundred tyrosine phosphorylation sites revealed new modes of regulation of phosphorylation of PAG, PI3K, and WASP while reconfirming previously established regulation of Itk, PLCγ, and Erk phosphorylation by SLP-76. The absence of SLP-76 also perturbed the phosphorylation of Src family kinases (SFKs) Lck and Fyn, and subsequently a large number of SFK-regulated signaling molecules. Altogether our data suggests unique modes of regulation of positive and negative feedback pathways in T cells by SLP-76, reconfirming its central role in the pathway.
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Affiliation(s)
- Lulu Cao
- Department of Chemistry, Brown University, Providence, Rhode Island, United States of America
| | - Yiyuan Ding
- Department of Chemistry, Brown University, Providence, Rhode Island, United States of America
| | - Norris Hung
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, United States of America
| | - Kebing Yu
- Department of Chemistry, Brown University, Providence, Rhode Island, United States of America
| | - Anna Ritz
- Department of Computer Science, Brown University, Providence, Rhode Island, United States of America
| | - Benjamin J. Raphael
- Department of Computer Science, Brown University, Providence, Rhode Island, United States of America
| | - Arthur R. Salomon
- Department of Chemistry, Brown University, Providence, Rhode Island, United States of America
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, United States of America
- * E-mail:
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