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Lotze MT, Olejniczak SH, Skokos D. CD28 co-stimulation: novel insights and applications in cancer immunotherapy. Nat Rev Immunol 2024:10.1038/s41577-024-01061-1. [PMID: 39054343 DOI: 10.1038/s41577-024-01061-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2024] [Indexed: 07/27/2024]
Abstract
Substantial progress in understanding T cell signalling, particularly with respect to T cell co-receptors such as the co-stimulatory receptor CD28, has been made in recent years. This knowledge has been instrumental in the development of innovative immunotherapies for patients with cancer, including immune checkpoint blockade antibodies, adoptive cell therapies, tumour-targeted immunostimulatory antibodies, and immunostimulatory small-molecule drugs that regulate T cell activation. Following the failed clinical trial of a CD28 superagonist antibody in 2006, targeted CD28 agonism has re-emerged as a technologically viable and clinically promising strategy for cancer immunotherapy. In this Review, we explore recent insights into the molecular functions and regulation of CD28. We describe how CD28 is central to the success of current cancer immunotherapies and examine how new questions arising from studies of CD28 as a clinical target have enhanced our understanding of its biological role and may guide the development of future therapeutic strategies in oncology.
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Affiliation(s)
- Michael T Lotze
- Department of Surgery, University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA, USA.
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA.
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA.
| | - Scott H Olejniczak
- Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA.
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2
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De Sousa Linhares A, Sharma S, Steinberger P, Leitner J. Transcriptional reprogramming via signaling domains of CD2, CD28, and 4-1BB. iScience 2024; 27:109267. [PMID: 38455974 PMCID: PMC10918215 DOI: 10.1016/j.isci.2024.109267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/23/2023] [Accepted: 02/14/2024] [Indexed: 03/09/2024] Open
Abstract
Costimulatory signals provided to T cells during antigen encounter have a decisive role in the outcome of immune responses. Here, we used chimeric receptors harboring the extracellular domain of mouse inducible T cell costimulator (mICOS) to study transcriptional activation mediated by cytoplasmic sequences of the major T cell costimulatory receptors CD28, 4-1BB, and CD2. The chimeric receptors were introduced in a T cell reporter platform that allows to simultaneously evaluate nuclear factor κB (NF-κB), NFAT, and AP-1 activation. Engagement of the chimeric receptors induced distinct transcriptional profiles. CD28 signaling activated all three transcription factors, whereas 4-1BB strongly promoted NF-κB and AP-1 but downregulated NFAT activity. CD2 signals resulted in the strongest upregulation of NFAT. Transcriptome analysis revealed pronounced and distinct gene expression signatures upon CD2 and 4-1BB signaling. Using the intracellular sequence of CD28, we exemplify that distinct signaling motifs endow chimeric receptors with different costimulatory capacities.
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Affiliation(s)
- Annika De Sousa Linhares
- Division of Immune Receptors and T Cell Activation, Center for Pathophysiology, Infectiology and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
- Loop lab Bio GmbH, Vienna, Austria
| | - Sumana Sharma
- MRC Translational Immune Discovery Unit John Radcliffe Hospital, University of Oxford, Oxford OX3 9DS, UK
| | - Peter Steinberger
- Division of Immune Receptors and T Cell Activation, Center for Pathophysiology, Infectiology and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
| | - Judith Leitner
- Division of Immune Receptors and T Cell Activation, Center for Pathophysiology, Infectiology and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
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3
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Quiniou SMA, Bengtén E, Boudinot P. Costimulatory receptors in the channel catfish: CD28 family members and their ligands. Immunogenetics 2024; 76:51-67. [PMID: 38197898 DOI: 10.1007/s00251-023-01327-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 12/10/2023] [Indexed: 01/11/2024]
Abstract
The CD28-B7 interaction is required to deliver a second signal necessary for T-cell activation. Additional membrane receptors of the CD28 and B7 families are also involved in immune checkpoints that positively or negatively regulate leukocyte activation, in particular T lymphocytes. BTLA is an inhibitory receptor that belongs to a third receptor family. Fish orthologs exist only for some of these genes, and the potential interactions between the corresponding ligands remain mostly unclear. In this work, we focused on the channel catfish (Ictalurus punctatus), a long-standing model for fish immunology, to analyze these co-stimulatory and co-inhibitory receptors. We identified one copy of cd28, ctla4, cd80/86, b7h1/dc, b7h3, b7h4, b7h5, two btla, and four b7h7 genes. Catfish CD28 contains the highly conserved mammalian cytoplasmic motif for PI3K and GRB2 recruitment, however this motif is absent in cyprinids. Fish CTLA4 share a C-terminal putative GRB2-binding site but lacks the mammalian PI3K/GRB2-binding motif. While critical V-domain residues for human CD80 or CD86 binding to CD28/CTLA4 show low conservation in fish CD80/86, C-domain residues are highly conserved, underscoring their significance. Catfish B7H1/DC had a long intracytoplasmic domain with a P-loop-NTPase domain that is absent in mammalian sequences, while the lack of NLS motif in fish B7H4 suggests this protein may not regulate cell growth when expressed intracellularly. Finally, there is a notable expansion of fish B7H7s, which likely play diverse roles in leukocyte regulation. Overall, our work contributes to a better understanding of fish leukocyte co-stimulatory and co-inhibitory receptors.
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Affiliation(s)
| | - Eva Bengtén
- Center for Immunology and Microbial Research, University of Mississippi Medical Center, 39216, Jackson, MS, USA
- Department of Cell and Molecular Biology, University of Mississippi Medical Center, 39216, Jackson, MS, USA
| | - Pierre Boudinot
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, 78350, France.
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4
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Vav Proteins in Development of the Brain: A Potential Relationship to the Pathogenesis of Congenital Zika Syndrome? Viruses 2022; 14:v14020386. [PMID: 35215978 PMCID: PMC8874935 DOI: 10.3390/v14020386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/07/2022] [Accepted: 02/10/2022] [Indexed: 12/07/2022] Open
Abstract
Zika virus (ZIKV) infection during pregnancy can result in a significant impact on the brain and eye of the developing fetus, termed congenital zika syndrome (CZS). At a morphological level, the main serious presentations of CZS are microcephaly and retinal scarring. At a cellular level, many cell types of the brain may be involved, but primarily neuronal progenitor cells (NPC) and developing neurons. Vav proteins have guanine exchange activity in converting GDP to GTP on proteins such as Rac1, Cdc42 and RhoA to stimulate intracellular signaling pathways. These signaling pathways are known to play important roles in maintaining the polarity and self-renewal of NPC pools by coordinating the formation of adherens junctions with cytoskeletal rearrangements. In developing neurons, these same pathways are adopted to control the formation and growth of neurites and mediate axonal guidance and targeting in the brain and retina. This review describes the role of Vavs in these processes and highlights the points of potential ZIKV interaction, such as (i) the binding and entry of ZIKV in cells via TAM receptors, which may activate Vav/Rac/RhoA signaling; (ii) the functional convergence of ZIKV NS2A with Vav in modulating adherens junctions; (iii) ZIKV NS4A/4B protein effects on PI3K/AKT in a regulatory loop via PPI3 to influence Vav/Rac1 signaling in neurite outgrowth; and (iv) the induction of SOCS1 and USP9X following ZIKV infection to regulate Vav protein degradation or activation, respectively, and impact Vav/Rac/RhoA signaling in NPC and neurons. Experiments to define these interactions will further our understanding of the molecular basis of CZS and potentially other developmental disorders stemming from in utero infections. Additionally, Vav/Rac/RhoA signaling pathways may present tractable targets for therapeutic intervention or molecular rationale for disease severity in CZS.
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5
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Braun LM, Zeiser R. Kinase Inhibition as Treatment for Acute and Chronic Graft- Versus-Host Disease. Front Immunol 2021; 12:760199. [PMID: 34868001 PMCID: PMC8635802 DOI: 10.3389/fimmu.2021.760199] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 10/28/2021] [Indexed: 01/25/2023] Open
Abstract
Allogeneic hematopoietic stem cell transplantation (allo-HCT) is a potentially curative therapy for patients suffering from hematological malignancies via the donor immune system driven graft-versus-leukemia effect. However, the therapy is mainly limited by severe acute and chronic graft-versus-host disease (GvHD), both being life-threatening complications after allo-HCT. GvHD develops when donor T cells do not only recognize remaining tumor cells as foreign, but also the recipient’s tissue, leading to a severe inflammatory disease. Typical GvHD target organs include the skin, liver and intestinal tract. Currently all approved strategies for GvHD treatment are immunosuppressive therapies, with the first-line therapy being glucocorticoids. However, therapeutic options for glucocorticoid-refractory patients are still limited. Novel therapeutic approaches, which reduce GvHD severity while preserving GvL activity, are urgently needed. Targeting kinase activity with small molecule inhibitors has shown promising results in preclinical animal models and clinical trials. Well-studied kinase targets in GvHD include Rho-associated coiled-coil-containing kinase 2 (ROCK2), spleen tyrosine kinase (SYK), Bruton’s tyrosine kinase (BTK) and interleukin-2-inducible T-cell kinase (ITK) to control B- and T-cell activation in acute and chronic GvHD. Janus Kinase 1 (JAK1) and 2 (JAK2) are among the most intensively studied kinases in GvHD due to their importance in cytokine production and inflammatory cell activation and migration. Here, we discuss the role of kinase inhibition as novel treatment strategies for acute and chronic GvHD after allo-HCT.
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Affiliation(s)
- Lukas M Braun
- Department of Medicine I, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Robert Zeiser
- Department of Medicine I, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,German Cancer Consortium (DKTK) Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Comprehensive Cancer Center Freiburg (CCCF), University of Freiburg, Freiburg, Germany.,Centre for Biological Signalling Studies (BIOSS) and Centre for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, Freiburg, Germany
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Andreotti AH, Joseph RE, Conley JM, Iwasa J, Berg LJ. Multidomain Control Over TEC Kinase Activation State Tunes the T Cell Response. Annu Rev Immunol 2019; 36:549-578. [PMID: 29677469 DOI: 10.1146/annurev-immunol-042617-053344] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Signaling through the T cell antigen receptor (TCR) activates a series of tyrosine kinases. Directly associated with the TCR, the SRC family kinase LCK and the SYK family kinase ZAP-70 are essential for all downstream responses to TCR stimulation. In contrast, the TEC family kinase ITK is not an obligate component of the TCR cascade. Instead, ITK functions as a tuning dial, to translate variations in TCR signal strength into differential programs of gene expression. Recent insights into TEC kinase structure have provided a view into the molecular mechanisms that generate different states of kinase activation. In resting lymphocytes, TEC kinases are autoinhibited, and multiple interactions between the regulatory and kinase domains maintain low activity. Following TCR stimulation, newly generated signaling modules compete with the autoinhibited core and shift the conformational ensemble to the fully active kinase. This multidomain control over kinase activation state provides a structural mechanism to account for ITK's ability to tune the TCR signal.
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Affiliation(s)
- Amy H Andreotti
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA; ,
| | - Raji E Joseph
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA; ,
| | - James M Conley
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA; ,
| | - Janet Iwasa
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, USA;
| | - Leslie J Berg
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA; ,
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7
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Signal Transduction Via Co-stimulatory and Co-inhibitory Receptors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1189:85-133. [PMID: 31758532 DOI: 10.1007/978-981-32-9717-3_4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
T-cell receptor (TCR)-mediated antigen-specific stimulation is essential for initiating T-cell activation. However, signaling through the TCR alone is not sufficient for inducing an effective response. In addition to TCR-mediated signaling, signaling through antigen-independent co-stimulatory or co-inhibitory receptors is critically important not only for the full activation and functional differentiation of T cells but also for the termination and suppression of T-cell responses. Many studies have investigated the signaling pathways underlying the function of each molecular component. Co-stimulatory and co-inhibitory receptors have no kinase activity, but their cytoplasmic region contains unique functional motifs and potential phosphorylation sites. Engagement of co-stimulatory receptors leads to recruitment of specific binding partners, such as adaptor molecules, kinases, and phosphatases, via recognition of a specific motif. Consequently, each co-stimulatory receptor transduces a unique pattern of signaling pathways. This review focuses on our current understanding of the intracellular signaling pathways provided by co-stimulatory and co-inhibitory molecules, including B7:CD28 family members, immunoglobulin, and members of the tumor necrosis factor receptor superfamily.
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8
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Reyes VE, Peniche AG. Helicobacter pylori Deregulates T and B Cell Signaling to Trigger Immune Evasion. Curr Top Microbiol Immunol 2019; 421:229-265. [PMID: 31123892 DOI: 10.1007/978-3-030-15138-6_10] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Helicobacter pylori is a prevalent human pathogen that successfully establishes chronic infection, which leads to clinically significant gastric diseases including chronic gastritis, peptic ulcer disease (PUD), and gastric cancer (GC). H. pylori is able to produce a persistent infection due in large part to its ability to hijack the host immune response. The host adaptive immune response is activated to strategically and specifically attack pathogens and normally clears them from the infected host. Since B and T lymphocytes are central mediators of adaptive immunity, in this chapter we review their development and the fundamental mechanisms regulating their activation in order to understand how some of the normal processes are subverted by H. pylori. In this review, we place particular emphasis on the CD4+ T cell responses, their subtypes, and regulatory mechanisms because of the expanding literature in this area related to H. pylori. T lymphocyte differentiation and function are finely orchestrated through a series of cell-cell interactions, which include immune checkpoint receptors. Among the immune checkpoint receptor family, there are some with inhibitory properties that are exploited by tumor cells to facilitate their immune evasion. Gastric epithelial cells (GECs), which act as antigen-presenting cells (APCs) in the gastric mucosa, are induced by H. pylori to express immune checkpoint receptors known to sway T lymphocyte function and thus circumvent effective T effector lymphocyte responses. This chapter reviews these and other mechanisms used by H. pylori to interfere with host immunity in order to persist.
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Affiliation(s)
- Victor E Reyes
- Department of Pediatrics, The University of Texas Medical Branch at Galveston, Galveston, TX, USA.
| | - Alex G Peniche
- Department of Pediatrics, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
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9
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γδT Cells Exacerbate Podocyte Injury via the CD28/B7-1-Phosphor-SRC Kinase Pathway. BIOMED RESEARCH INTERNATIONAL 2018; 2018:5647120. [PMID: 29862277 PMCID: PMC5976931 DOI: 10.1155/2018/5647120] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 03/08/2018] [Accepted: 04/08/2018] [Indexed: 01/25/2023]
Abstract
Primary nephrotic syndrome (PNS) is a devastating pediatric disorder. However, its mechanism remains unclear. Previous studies detected B7-1 in podocytes; meanwhile, γδT cells play pivotal roles in immune diseases. Therefore, this study aimed to assess whether and how γδT cells impact podocytes via the CD28/B7-1 pathway. WT and TCRδ−/− mice were assessed. LPS was used to induce nephropathy. Total γδT and CD28+γδT cells were quantitated in mouse spleen and kidney samples. B7-1 and phosphor-SRC levels in the kidney were detected as well. In vitro, γδT cells from the mouse spleen were cocultured with mouse podocytes, and apoptosis rate and phosphor-SRC expression in podocytes were assessed. Compared with control mice, WT mice with LPS nephropathy showed increased amounts of γδT cells in the kidney. Kidney injury was alleviated in TCRδ−/− mice. Meanwhile, B7-1 and phosphor-SRC levels were increased in the kidney from WT mice with LPS nephropathy. CD28+γδT cells were decreased, indicating CD28 may play a role in LPS nephropathy. Immunofluorescence colocalization analysis revealed a tight association of γδT cells with B7-1 in the kidney. High B7-1 expression was detected in podocytes treated with LPS. Podocytes cocultured with γδT cells showed higher phosphor-SRC and apoptosis rate than other cell groups. Furthermore, CD28/B7-1 blockage with CTLA4-Ig in vitro relieved podocyte injury. γδT cells exacerbate podocyte injury via CD28/B7-1 signaling, with downstream involvement of phosphor-SRC. The CD28/B7-1 blocker CTLA4-Ig prevented progressive podocyte injury, providing a potential therapeutic tool for PNS.
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10
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Zumerle S, Molon B, Viola A. Membrane Rafts in T Cell Activation: A Spotlight on CD28 Costimulation. Front Immunol 2017; 8:1467. [PMID: 29163534 PMCID: PMC5675840 DOI: 10.3389/fimmu.2017.01467] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 10/19/2017] [Indexed: 12/28/2022] Open
Abstract
Spatiotemporal compartmentalization of signaling pathways and second messengers is pivotal for cell biology and membrane rafts are, therefore, required for several lymphocyte functions. On the other hand, T cells have the specific necessity of tuning signaling amplification depending on the context in which the antigen is presented. In this review, we discuss of membrane rafts in the context of T cell signaling, focusing on CD28-mediated costimulation.
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Affiliation(s)
- Sara Zumerle
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,Venetian Institute of Molecular Medicine (VIMM), Padova, Italy
| | - Barbara Molon
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,Venetian Institute of Molecular Medicine (VIMM), Padova, Italy
| | - Antonella Viola
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,Pediatric Research Institute "Citta della Speranza", Padova, Italy
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11
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Ul-Haq Z, Effendi JS, Ashraf S, Bkhaitan MM. Atom and receptor based 3D QSAR models for generating new conformations from pyrazolopyrimidine as IL-2 inducible tyrosine kinase inhibitors. J Mol Graph Model 2017; 74:379-395. [PMID: 28499271 DOI: 10.1016/j.jmgm.2017.03.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 03/24/2017] [Accepted: 03/24/2017] [Indexed: 10/19/2022]
Abstract
In the current study, quantitative three-dimensional structure-activity-relationship (3D-QSAR) method was performed to design a model for new chemical entities by utilizing pyrazolopyrimidines. Their inhibiting activity on receptor IL-2 Itk correlates descriptors based on topology and hydrophobicity. The best model developed by ligand-based (atom-based) approach has correlation-coefficient of r2: 0.987 and cross-validated squared correlation-coefficient of q2: 0.541 with an external prediction capability of r2: 0.944. Whereas the best selected model developed by structured-based (receptor-based) approach has correlation-coefficient of r2: 0.987, cross-validated squared correlation-coefficient of q2: 0.637 with an external predictive ability of r2: 0.941. The statistical parameters prove that structure-based gave a better model to design new chemical scaffolds. The results achieved indicated that hydrophobicity at R1 location play a vital role in the inhibitory activity and introduction of appropriately bulky and strongly hydrophobic-groups at position 3 of the terminal phenyl-group which is highly significant to enhance the activity. Six new pyrazolopyrimidine derivatives were designed. Docking simulation study was carried out and their inhibitory activity was predicted by the best structure based model with predictive activity of ranging from 8.43 to 8.85 log unit. The interacting residues PHE435, ASP500, LYS391, GLU436, MET438, CYS442, ILE369, VAL377 of PDB 4HCT were studied with respect to type of bonding with the new compounds. This study was aimed to search out more potent inhibitors of IL-2 Itk.
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Affiliation(s)
- Zaheer Ul-Haq
- Dr. Panjwani Canter for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
| | - Juweria Shahrukh Effendi
- Dr. Panjwani Canter for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan
| | - Sajda Ashraf
- Dr. Panjwani Canter for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan
| | - Majdi M Bkhaitan
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Umm Al-Qura University, Makkah, KSA, Saudi Arabia
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12
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Dobbins J, Gagnon E, Godec J, Pyrdol J, Vignali DAA, Sharpe AH, Wucherpfennig KW. Binding of the cytoplasmic domain of CD28 to the plasma membrane inhibits Lck recruitment and signaling. Sci Signal 2016; 9:ra75. [PMID: 27460989 DOI: 10.1126/scisignal.aaf0626] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The T cell costimulatory receptor CD28 is required for the full activation of naïve T cells and for the development and maintenance of Foxp3(+) regulatory T (Treg) cells. We showed that the cytoplasmic domain of CD28 was bound to the plasma membrane in resting cells and that ligand binding to CD28 resulted in its release. Membrane binding by the CD28 cytoplasmic domain required two clusters of basic amino acid residues, which interacted with the negatively charged inner leaflet of the plasma membrane. These same clusters of basic residues also served as interaction sites for Lck, a Src family kinase critical for CD28 function. This signaling complex was further stabilized by the Lck-mediated phosphorylation of CD28 Tyr(207) and the subsequent binding of the Src homology 2 (SH2) domain of Lck to this phosphorylated tyrosine. Mutation of the basic clusters in the CD28 cytoplasmic domain reduced the recruitment to the CD28-Lck complex of protein kinase Cθ (PKCθ), which serves as a key effector kinase in the CD28 signaling pathway. Consequently, mutation of either a basic cluster or Tyr(207) impaired CD28 function in mice as shown by the reduced thymic differentiation of FoxP3(+) Treg cells. On the basis of these results, we propose a previously undescribed model for the initiation of CD28 signaling.
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Affiliation(s)
- Jessica Dobbins
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02115, USA. Program in Immunology, Harvard Medical School, Boston, MA 02115, USA
| | - Etienne Gagnon
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Jernej Godec
- Program in Immunology, Harvard Medical School, Boston, MA 02115, USA. Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Jason Pyrdol
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Dario A A Vignali
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA. Tumor Microenvironment Center, University of Pittsburgh Cancer Institute, Pittsburgh, PA 15232, USA
| | - Arlene H Sharpe
- Program in Immunology, Harvard Medical School, Boston, MA 02115, USA. Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Kai W Wucherpfennig
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02115, USA. Program in Immunology, Harvard Medical School, Boston, MA 02115, USA. Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA.
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13
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Porciello N, Tuosto L. CD28 costimulatory signals in T lymphocyte activation: Emerging functions beyond a qualitative and quantitative support to TCR signalling. Cytokine Growth Factor Rev 2016; 28:11-9. [PMID: 26970725 DOI: 10.1016/j.cytogfr.2016.02.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 02/22/2016] [Indexed: 01/22/2023]
Abstract
CD28 is one of the most important co-stimulatory receptors necessary for full T lymphocyte activation. By binding its cognate ligands, B7.1/CD80 or B7.2/CD86, expressed on the surface of professional antigen presenting cells (APC), CD28 initiates several signalling cascades, which qualitatively and quantitatively support T cell receptor (TCR) signalling. More recent data evidenced that human CD28 can also act as a TCR-independent signalling unit, by delivering specific signals, which regulate the expression of pro-inflammatory cytokine/chemokines. Despite the enormous progresses made in identifying the mechanisms and molecules involved in CD28 signalling properties, much remains to be elucidated, especially in the light of the functional differences observed between human and mouse CD28. In this review we provide an overview of the current mechanisms and molecules through which CD28 support TCR signalling and highlight recent findings on the specific signalling motifs that regulate the unique pro-inflammatory activity of human CD28.
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Affiliation(s)
- Nicla Porciello
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, 00185 Rome, Italy
| | - Loretta Tuosto
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Biology and Biotechnology Charles Darwin, Sapienza University of Rome, 00185 Rome, Italy.
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14
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Schutt SD, Fu J, Nguyen H, Bastian D, Heinrichs J, Wu Y, Liu C, McDonald DG, Pidala J, Yu XZ. Inhibition of BTK and ITK with Ibrutinib Is Effective in the Prevention of Chronic Graft-versus-Host Disease in Mice. PLoS One 2015; 10:e0137641. [PMID: 26348529 PMCID: PMC4562702 DOI: 10.1371/journal.pone.0137641] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 08/20/2015] [Indexed: 01/01/2023] Open
Abstract
Bruton’s Tyrosine Kinase (BTK) and IL-2 Inducible T-cell Kinase (ITK) are enzymes responsible for the phosphorylation and activation of downstream effectors in the B-cell receptor (BCR) signaling and T cell receptor (TCR) signaling pathways, respectively. Ibrutinib is an FDA-approved potent inhibitor of both BTK and ITK that impairs B-cell and T-cell function. CD4 T cells and B cells are essential for the induction of chronic graft-versus-host disease (cGVHD). We evaluated these targets by testing the ability of Ibrutinib to prevent or ameliorate cGVHD, which is one of the major complications for patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). We found that Ibrutinib significantly alleviated cGVHD across four different mouse models, accompanied by increased long-term survival and reduced clinical score. The clinical improvements in Ibrutinib-treated recipients were associated with decreased serum-autoantibodies, costimulatory molecule activation, B-cell proliferation, and glomerulonephritis compared to vehicle controls. Ibrutinib was also able to alleviate the clinical manifestations in acute GVHD (aGVHD), where the recipients were given grafts with or without B cells, suggesting that an inhibitory effect of Ibrutinib on T cells contributes to a reduction in both aGVHD and cGVHD pathogenesis. An effective prophylactic regimen is still lacking to both reduce the incidence and severity of human cGVHD following allo-HSCT. Our study shows that Ibrutinib is an effective prophylaxis against several mouse models of cGVHD with minimal toxicity and could be a promising strategy to combat human cGVHD clinically.
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Affiliation(s)
- Steven D. Schutt
- Department of Microbiology & Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Jianing Fu
- Department of Microbiology & Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
- Cancer Biology PhD Program, University of South Florida and H. Lee Moffitt Cancer Center, Tampa, Florida, United States of America
| | - Hung Nguyen
- Department of Microbiology & Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - David Bastian
- Department of Microbiology & Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Jessica Heinrichs
- Department of Microbiology & Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Yongxia Wu
- Department of Microbiology & Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Chen Liu
- Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Daniel G. McDonald
- Department of Radiation Oncology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Joseph Pidala
- Blood and Bone Marrow Transplant Department, Moffitt Cancer Center, Tampa, Florida, United States of America
| | - Xue-Zhong Yu
- Department of Microbiology & Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
- Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America
- * E-mail:
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15
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Muscolini M, Camperio C, Porciello N, Caristi S, Capuano C, Viola A, Galandrini R, Tuosto L. Phosphatidylinositol 4–Phosphate 5–Kinase α and Vav1 Mutual Cooperation in CD28-Mediated Actin Remodeling and Signaling Functions. THE JOURNAL OF IMMUNOLOGY 2015; 194:1323-1333. [DOI: 10.4049/jimmunol.1401643] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Abstract
Phosphatidylinositol 4,5–biphosphate (PIP2) is a cell membrane phosphoinositide crucial for cell signaling and activation. Indeed, PIP2 is a pivotal source for second messenger generation and controlling the activity of several proteins regulating cytoskeleton reorganization. Despite its critical role in T cell activation, the molecular mechanisms regulating PIP2 turnover remain largely unknown. In human primary CD4+ T lymphocytes, we have recently demonstrated that CD28 costimulatory receptor is crucial for regulating PIP2 turnover by allowing the recruitment and activation of the lipid kinase phosphatidylinositol 4–phosphate 5–kinase (PIP5Kα). We also identified PIP5Kα as a key modulator of CD28 costimulatory signals leading to the efficient T cell activation. In this study, we extend these data by demonstrating that PIP5Kα recruitment and activation is essential for CD28-mediated cytoskeleton rearrangement necessary for organizing a complete signaling compartment leading to downstream signaling functions. We also identified Vav1 as the linker molecule that couples the C-terminal proline-rich motif of CD28 to the recruitment and activation of PIP5Kα, which in turn cooperates with Vav1 in regulating actin polymerization and CD28 signaling functions.
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Affiliation(s)
- Michela Muscolini
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
| | - Cristina Camperio
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
| | - Nicla Porciello
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
| | - Silvana Caristi
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
| | - Cristina Capuano
- †Department of Experimental Medicine, Sapienza University, 00185 Rome, Italy
| | - Antonella Viola
- ‡The Venetian Institute of Molecular Medicine, Padova 35129, Italy; and
- §Department of Biomedical Sciences, University of Padova, Padova 35121, Italy
| | | | - Loretta Tuosto
- *Department of Biology and Biotechnology “Charles Darwin,” Pasteur Institute–Cenci Bolognetti Foundation, Sapienza University, 00185 Rome, Italy
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16
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Abstract
To be the recipient of the E. E. Just Award for 2014 is one of my greatest honors, as this is a truly rarefied group. In this essay, I try to trace my path to becoming a scientist to illustrate that multiple paths can lead to science. I also highlight that I did not build my career alone. Rather, I had help from many and have tried to pay it forward. Finally, as the country marches toward a minority majority, I echo the comments of previous E. E. Just Award recipients on the state of underrepresented minorities in science.
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Affiliation(s)
- Avery August
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853
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17
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Chylek LA, Akimov V, Dengjel J, Rigbolt KTG, Hu B, Hlavacek WS, Blagoev B. Phosphorylation site dynamics of early T-cell receptor signaling. PLoS One 2014; 9:e104240. [PMID: 25147952 PMCID: PMC4141737 DOI: 10.1371/journal.pone.0104240] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/07/2014] [Indexed: 11/18/2022] Open
Abstract
In adaptive immune responses, T-cell receptor (TCR) signaling impacts multiple cellular processes and results in T-cell differentiation, proliferation, and cytokine production. Although individual protein-protein interactions and phosphorylation events have been studied extensively, we lack a systems-level understanding of how these components cooperate to control signaling dynamics, especially during the crucial first seconds of stimulation. Here, we used quantitative proteomics to characterize reshaping of the T-cell phosphoproteome in response to TCR/CD28 co-stimulation, and found that diverse dynamic patterns emerge within seconds. We detected phosphorylation dynamics as early as 5 s and observed widespread regulation of key TCR signaling proteins by 30 s. Development of a computational model pointed to the presence of novel regulatory mechanisms controlling phosphorylation of sites with central roles in TCR signaling. The model was used to generate predictions suggesting unexpected roles for the phosphatase PTPN6 (SHP-1) and shortcut recruitment of the actin regulator WAS. Predictions were validated experimentally. This integration of proteomics and modeling illustrates a novel, generalizable framework for solidifying quantitative understanding of a signaling network and for elucidating missing links.
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Affiliation(s)
- Lily A. Chylek
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
- Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, United States of America
| | - Vyacheslav Akimov
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
| | - Jörn Dengjel
- Department of Dermatology, Medical Center; Freiburg Institute for Advanced Studies (FRIAS); BIOSS Centre for Biological Signalling Studies; ZBSA Center for Biological Systems Analysis, University of Freiburg, Freiburg, Germany
| | - Kristoffer T. G. Rigbolt
- Department of Dermatology, Medical Center; Freiburg Institute for Advanced Studies (FRIAS); BIOSS Centre for Biological Signalling Studies; ZBSA Center for Biological Systems Analysis, University of Freiburg, Freiburg, Germany
| | - Bin Hu
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - William S. Hlavacek
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
- Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Blagoy Blagoev
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark
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18
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Pennock ND, White JT, Cross EW, Cheney EE, Tamburini BA, Kedl RM. T cell responses: naive to memory and everything in between. ADVANCES IN PHYSIOLOGY EDUCATION 2013; 37:273-83. [PMID: 24292902 PMCID: PMC4089090 DOI: 10.1152/advan.00066.2013] [Citation(s) in RCA: 290] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 08/31/2013] [Indexed: 05/08/2023]
Affiliation(s)
- Nathan D Pennock
- Integrated Department of Immunology, University of Colorado Denver, Denver, Colorado
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19
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Witsenburg JJ, Glauner H, Müller JP, Groenewoud JMM, Roth G, Böhmer FD, Adjobo-Hermans MJW, Brock R. A quantitative assessment of costimulation and phosphatase activity on microclusters in early T cell signaling. PLoS One 2013; 8:e79277. [PMID: 24205378 PMCID: PMC3813591 DOI: 10.1371/journal.pone.0079277] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Accepted: 09/27/2013] [Indexed: 01/15/2023] Open
Abstract
T cell signaling is triggered through stimulation of the T cell receptor and costimulatory receptors. Receptor activation leads to the formation of membrane-proximal protein microclusters. These clusters undergo tyrosine phosphorylation and organize multiprotein complexes thereby acting as molecular signaling platforms. Little is known about how the quantity and phosphorylation levels of microclusters are affected by costimulatory signals and the activity of specific signaling proteins. We combined micrometer-sized, microcontact printed, striped patterns of different stimuli and simultaneous analysis of different cell strains with image processing protocols to address this problem. First, we validated the stimulation protocol by showing that high expression levels CD28 result in increased cell spreading. Subsequently, we addressed the role of costimulation and a specific phosphotyrosine phosphatase in cluster formation by including a SHP2 knock-down strain in our system. Distinguishing cell strains using carboxyfluorescein succinimidyl ester enabled a comparison within single samples. SHP2 exerted its effect by lowering phosphorylation levels of individual clusters while CD28 costimulation mainly increased the number of signaling clusters and cell spreading. These effects were observed for general tyrosine phosphorylation of clusters and for phosphorylated PLCγ1. Our analysis enables a clear distinction between factors determining the number of microclusters and those that act on these signaling platforms.
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Affiliation(s)
- J. Joris Witsenburg
- Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Heike Glauner
- Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Jörg P. Müller
- Institute for Molecular Cell Biology, Jena University Hospital, Jena, Germany
| | - Johannes M. M. Groenewoud
- Department of Medical Technology Assessment, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Günter Roth
- Laboratory for MEMS Applications, Department of Microsystems Engineering (IMTEK), Albert Ludwigs University, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University, Freiburg, Germany
| | | | - Merel J. W. Adjobo-Hermans
- Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Roland Brock
- Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
- * E-mail:
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20
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Ogawa S, Watanabe M, Sakurai Y, Inutake Y, Watanabe S, Tai X, Abe R. CD28 signaling in primary CD4+ T cells: identification of both tyrosine phosphorylation-dependent and phosphorylation-independent pathways. Int Immunol 2013; 25:671-81. [DOI: 10.1093/intimm/dxt028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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21
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Benzing C, Rossy J, Gaus K. Do signalling endosomes play a role in T cell activation? FEBS J 2013; 280:5164-76. [PMID: 23834225 DOI: 10.1111/febs.12427] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 06/02/2013] [Accepted: 06/25/2013] [Indexed: 11/29/2022]
Abstract
Signalling endosomes represent a general mechanism for modulating and compartmentalizing cell signalling, which is achieved by delineating specific spatial environments and connecting the plasma membrane with intracellular events. The molecular composition of vesicles, together with their targeting mechanisms and endocytic routes, contributes to the outcome of signalling pathways that are initiated either at the plasma membrane or within endosomes themselves. In T cell signalling, it is now accepted that the spatial distribution of signalling proteins is central to T cell activation not only at the immunological synapse, but also in endosomes travelling to and from the plasma membrane. In addition, there is a global rearrangement of the endosome machinery upon T cell activation, and emerging experimental evidence suggests that vesicles in T cells contain key T cell signalling proteins. We review the various mechanisms by which endosomes contribute to signalling pathways and consider whether signalling endosomes play a role in T cell signalling.
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Affiliation(s)
- Carola Benzing
- Centre for Vascular Research and Australian Centre for Nanomedicine, University of New South Wales, Sydney, Australia
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22
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The zinc-binding region of IL-2 inducible T cell kinase (Itk) is required for interaction with Gα13 and activation of serum response factor. Int J Biochem Cell Biol 2013; 45:1074-82. [PMID: 23454662 DOI: 10.1016/j.biocel.2013.02.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 02/04/2013] [Accepted: 02/18/2013] [Indexed: 11/20/2022]
Abstract
Tec family kinases play critical roles in the activation of immune cells. In particular, Itk is important for the activation of T cells via the T cell Receptor (TcR), however, molecules that cooperate with Itk to activate downstream targets remain little explored. Here we show that Itk interacts with the heterotrimeric G-protein α subunit Gα13 during TcR triggering. This interaction requires membrane localization of both partners, and is partially dependent on GDP- and GTP-bound states of Gα13. Furthermore, we find that Itk interacts with Gα13 via the zinc binding regions within its Tec homology domain. The interaction between Itk and Gα13 also results in tyrosine phosphorylation of Gα13, however this is not required for the interaction. Itk enhances Gα13 mediated activation of serum response factor (SRF) transcriptional activity dependent on its ability to interact with Gα13, but its kinase activity is not required to enhance SRF activity. These data reveal a new pathway regulated by Itk in cells, and suggest cross talk between Itk and G-protein signaling downstream of the TcR.
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23
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Isakov N, Altman A. PKC-theta-mediated signal delivery from the TCR/CD28 surface receptors. Front Immunol 2012; 3:273. [PMID: 22936936 PMCID: PMC3425079 DOI: 10.3389/fimmu.2012.00273] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 08/09/2012] [Indexed: 12/23/2022] Open
Abstract
Protein kinase C-theta (PKCθ) is a key enzyme in T lymphocytes, where it plays an important role in signal transduction downstream of the activated T cell antigen receptor (TCR) and the CD28 costimulatory receptor. Interest in PKCθ as a potential drug target has increased following recent findings that PKCθ is essential for harmful inflammatory responses mediated by Th2 (allergies) and Th17 (autoimmunity) cells as well as for graft-versus-host disease (GvHD) and allograft rejection, but is dispensable for beneficial responses such as antiviral immunity and graft-versus-leukemia (GvL) response. TCR/CD28 engagement triggers the translocation of the cytosolic PKCθ to the plasma membrane (PM), where it localizes at the center of the immunological synapse (IS), which forms at the contact site between an antigen-specific T cell and antigen-presenting cells (APC). However, the molecular basis for this unique localization, and whether it is required for its proper function have remained unresolved issues until recently. Our recent study resolved these questions by demonstrating that the unique V3 (hinge) domain of PKCθ and, more specifically, a proline-rich motif within this domain, is essential and sufficient for its localization at the IS, where it is anchored to the cytoplasmic tail of CD28 via an indirect mechanism involving Lck protein tyrosine kinase (PTK) as an intermediate. Importantly, the association of PKCθ with CD28 is essential not only for IS localization, but also for PKCθ-mediated activation of downstream signaling pathways, including the transcription factors NF-κB and NF-AT, which are essential for productive T cell activation. Hence, interference with formation of the PKCθ-Lck-CD28 complex provides a promising basis for the design of novel, clinically useful allosteric PKCθ inhibitors. An additional recent study demonstrated that TCR triggering activates the germinal center kinase (GSK)-like kinase (GLK) and induces its association with the SLP-76 adaptor at the IS, where GLK phosphorylates the activation loop of PKCθ, converting it into an active enzyme. This recent progress, coupled with the need to study the biology of PKCθ in human T cells, is likely to facilitate the development of PKCθ-based therapeutic modalities for T cell-mediated diseases.
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Affiliation(s)
- Noah Isakov
- The Shraga Segal Department of Microbiology and Immunology, Faculty of Health Sciences and the Cancer Research Center, Ben-Gurion University of the Negev Beer Sheva, Israel
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24
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Guo W, Liu R, Ono Y, Ma AH, Martinez A, Sanchez E, Wang Y, Huang W, Mazloom A, Li J, Ning J, Maverakis E, Lam KS, Kung HJ. Molecular characteristics of CTA056, a novel interleukin-2-inducible T-cell kinase inhibitor that selectively targets malignant T cells and modulates oncomirs. Mol Pharmacol 2012; 82:938-47. [PMID: 22899868 DOI: 10.1124/mol.112.079889] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Interleukin-2-inducible T-cell kinase (Itk) is a member of the Btk (Bruton's tyrosine kinase) family of tyrosine kinases. Itk plays an important role in normal T-cell functions and in the pathophysiology of both autoimmune diseases and T-cell malignancies. Here, we describe the initial characterization of a selective inhibitor, 7-benzyl-1-(3-(piperidin-1-yl)propyl)-2-(4-(pyridin-4-yl)phenyl)-1H-imidazo[4,5-g]quinoxalin-6(5H)-one (CTA056), that was developed through screening a 9600-compound combinatorial solution phase library, followed by molecular modeling, and extensive structure-activity relationship studies. CTA056 exhibits the highest inhibitory effects toward Itk, followed by Btk and endothelial and epithelial tyrosine kinase. Among the 41 cancer cell lines analyzed, CTA056 selectively targets acute lymphoblastic T-cell leukemia and cutaneous T-cell lymphoma. Normal T cells are minimally affected. Incubation of Jurkat and MOLT-4 cells with CTA056 resulted in the inhibition of the phosphorylation of Itk and its effectors including PLC-γ, Akt, and extracellular signal-regulated kinase, as well as the decreased secretion of targeted genes such as interleukin-2 and interferon-γ. Jurkat cells also underwent apoptosis in a dose-dependent manner when incubated with CTA056. The potent apoptosis-inducing potential of CTA056 is reflected by the significant modulation of microRNAs involved in survival pathways and oncogenesis. The in vitro cytotoxic effect on malignant T cells is further validated in a xenograft model. The selective expression and activation of Itk in malignant T cells, as well as the specificity of CTA056 for Itk, make this molecule a potential therapeutic agent for the treatment of T-cell leukemia and lymphoma.
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Affiliation(s)
- Wenchang Guo
- Department of Biochemistry and Molecular Medicine,,University of California Davis, Sacramento, California 95817, USA
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25
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Boucheron N, Ellmeier W. The Role of Tec Family Kinases in the Regulation of T-helper-cell Differentiation. Int Rev Immunol 2012; 31:133-54. [DOI: 10.3109/08830185.2012.664798] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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26
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Kannan Y, Wilson MS. TEC and MAPK Kinase Signalling Pathways in T helper (T H) cell Development, T H2 Differentiation and Allergic Asthma. JOURNAL OF CLINICAL & CELLULAR IMMUNOLOGY 2012; Suppl 12:11. [PMID: 24116341 PMCID: PMC3792371 DOI: 10.4172/2155-9899.s12-011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Significant advances in our understanding of the signalling events during T cell development and differentiation have been made in the past few decades. It is clear that ligation of the T cell receptor (TCR) triggers a series of proximal signalling cascades regulated by an array of protein kinases. These orchestrated and highly regulated series of events, with differential requirements of particular kinases, highlight the disparities between αβ+CD4+ T cells. Throughout this review we summarise both new and old studies, highlighting the role of Tec and MAPK in T cell development and differentiation with particular focus on T helper 2 (TH2) cells. Finally, as the allergy epidemic continues, we feature the role played by TH2 cells in the development of allergy and provide a brief update on promising kinase inhibitors that have been tested in vitro, in pre-clinical disease models in vivo and into clinical studies.
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Affiliation(s)
- Yashaswini Kannan
- Division of Molecular Immunology, National Institute for Medical Research, MRC, London, NW7 1AA, UK
| | - Mark S. Wilson
- Division of Molecular Immunology, National Institute for Medical Research, MRC, London, NW7 1AA, UK
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27
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Itk: the rheostat of the T cell response. JOURNAL OF SIGNAL TRANSDUCTION 2011; 2011:297868. [PMID: 21747996 PMCID: PMC3116522 DOI: 10.1155/2011/297868] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 01/19/2011] [Indexed: 12/28/2022]
Abstract
The nonreceptor tyrosine kinase Itk plays a key role in TCR-initiated signaling that directly and significantly affects the regulation of PLCγ1 and the consequent mobilization of Ca2+. Itk also participates in the regulation of cytoskeletal reorganization as well as cellular adhesion, which is necessary for a productive T cell response. The functional cellular outcome of these molecular regulations by Itk renders it an important mediator of T cell development and differentiation. This paper encompasses the structure of Itk, the signaling parameters leading to Itk activation, and Itk effects on molecular pathways resulting in functional cellular outcomes. The incorporation of these factors persuades one to believe that Itk serves as a modulator, or rheostat, critically fine-tuning the T cell response.
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28
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Riha P, Rudd CE. CD28 co-signaling in the adaptive immune response. SELF NONSELF 2010; 1:231-240. [PMID: 21487479 DOI: 10.4161/self.1.3.12968] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 07/12/2010] [Indexed: 12/20/2022]
Abstract
T-cell proliferation and function depends on signals from the antigen-receptor complex (TCR/CD3) and by various co-receptors such as CD28 and CTLA-4. The balance of positive and negative signals determines the outcome of the T-cell response to foreign and self-antigen. CD28 is a prominent co-receptor in naïve and memory T-cell responses. Its blockade has been exploited clinically to dampen T-cell responses to self-antigen. Current evidence shows that CD28 both potentiates TCR signaling and engages a unique array of mediators (PI3K, Grb2, FLNa) in the regulation of aspects of T-cell signaling including the transcription factor NFkB. In this mini-review, we provide an up-to-date overview of our understanding of the signaling mechanisms that underlie CD28 function and its potential application to the modulation of reactivity to autoimmunity.
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Affiliation(s)
- Pavel Riha
- Cell Signaling Section; Department of Pathology; University of Cambridge; Cambridge, UK
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29
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Natarajan M, August A, Henderson AJ. Combinatorial signals from CD28 differentially regulate human immunodeficiency virus transcription in T cells. J Biol Chem 2010; 285:17338-47. [PMID: 20368329 DOI: 10.1074/jbc.m109.085324] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Activation through the T-cell receptor and the costimulatory receptor CD28 supports efficient HIV transcription as well as reactivation of latent provirus. To characterize critical signals associated with CD28 that regulate HIV-1 transcription, we generated a library of chimeric CD28 receptors that harbored different combinations of key tyrosine residues in the cytoplasmic tail, Tyr-173, Tyr-188, Tyr-191, and Tyr-200. We found that Tyr-191 and Tyr-200 induce HIV-1 transcription via the activation of NF-kappaB and its recruitment to the HIV-long terminal repeat. Tyr-188 modifies positive and negative signals associated with CD28. Importantly, signaling through Tyr-188, Tyr-191, and Tyr-200 is required to overcome the inhibition posed by Tyr-173. CD28 also regulates P-TEFb activity, which is necessary for HIV-1 transcription processivity, by limiting the release of P-TEFb from the HEXIM1-7SK inhibitory complex in response to T-cell receptor signaling. Our studies reveal that CD28 regulates HIV-1 provirus transcription through a complex interplay of positive and negative signals that may be manipulated to control HIV-1 transcription and replication.
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Affiliation(s)
- Malini Natarajan
- Intercollege Graduate Degree Program in Immunology and Infectious Disease, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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30
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Weatherly K, Braun MY. Organ transplantation: modulation of T-cell activation pathways initiated by cell surface receptors to suppress graft rejection. Methods Mol Biol 2010; 677:419-30. [PMID: 20941624 DOI: 10.1007/978-1-60761-869-0_26] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
T-cell activation depends upon two types of signals: a T-cell-receptor-mediated antigen-specific signal and several non-antigen-specific ones provided by the engagement of costimulatory and/or inhibitory T-cell surface molecules. In clinical transplantation, T-cell costimulatory/inhibitory molecules are involved in determining cytokine production, vascular endothelial cell damage, and induction of transplant rejection. Several of the latest new immunotherapeutic strategies being currently developed to control graft rejection aim at inhibiting alloreactive T-cell function by regulating activating and costimulatory/inhibitory signals to T cells. This article describes the recent development and potential application of these therapies in experimental and pre-clinical transplantation.
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Affiliation(s)
- Kathleen Weatherly
- Institute for Medical Immunology, Université Libre de Bruxelles, Gosselies, Belgium
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Susaki K, Kitanaka A, Dobashi H, Kubota Y, Kittaka K, Kameda T, Yamaoka G, Mano H, Mihara K, Ishida T. Tec protein tyrosine kinase inhibits CD25 expression in human T-lymphocyte. Immunol Lett 2009; 127:135-42. [PMID: 19883687 DOI: 10.1016/j.imlet.2009.10.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 10/21/2009] [Accepted: 10/23/2009] [Indexed: 11/19/2022]
Abstract
The Tec protein tyrosine kinase (PTK) belongs to a group of structurally related nonreceptor PTKs that also includes Btk, Itk, Rlk, and Bmx. Previous studies have suggested that these kinases play important roles in hematopoiesis and in the lymphocyte signaling pathway. Despite evidence suggesting the involvement of Tec in the T-lymphocyte activation pathway via T-cell receptor (TCR) and CD28, Tec's role in T-lymphocytes remains unclear because of the lack of apparent defects in T-lymphocyte function in Tec-deficient mice. In this study, we investigated the role of Tec in human T-lymphocyte using the Jurkat T-lymphoid cell line stably transfected with a cDNA encoding Tec. We found that the expression of wild-type Tec inhibited the expression of CD25 induced by TCR cross-linking. Second, we observed that LFM-A13, a selective inhibitor of Tec family PTK, rescued the suppression of TCR-induced CD25 expression observed in wild-type Tec-expressing Jurkat cells. In addition, expression of kinase-deleted Tec did not alter the expression level of CD25 after TCR ligation. We conclude that Tec PTK mediates signals that negatively regulate CD25 expression induced by TCR cross-linking. This, in turn, implies that this PTK plays a role in the attenuation of IL-2 activity in human T-lymphocytes.
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Affiliation(s)
- Kentaro Susaki
- Division of Endocrinology and Metabolism, Hematology, Rheumatology, and Respiratory Medicine, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
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Sahu N, August A. ITK inhibitors in inflammation and immune-mediated disorders. Curr Top Med Chem 2009; 9:690-703. [PMID: 19689375 DOI: 10.2174/156802609789044443] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Interleukin-2-inducible T cell kinase (ITK) is a non-receptor tyrosine kinase expressed in T cells, NKT cells and mast cells which plays a crucial role in regulating the T cell receptor (TCR), CD28, CD2, chemokine receptor CXCR4, and FcepsilonR-mediated signaling pathways. In T cells, ITK is an important mediator for actin reorganization, activation of PLCgamma, mobilization of calcium, and activation of the NFAT transcription factor. ITK plays an important role in the secretion of IL-2, but more critically, also has a pivotal role in the secretion of Th2 cytokines, IL-4, IL-5 and IL-13. As such, ITK has been shown to regulate the development of effective Th2 response during allergic asthma as well as infections of parasitic worms. This ability of ITK to regulate Th2 responses, along with its pattern of expression, has led to the proposal that it would represent an excellent target for Th2-mediated inflammation. We discuss here the possibilities and pitfalls of targeting ITK for inflammatory disorders.
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Affiliation(s)
- Nisebita Sahu
- Department of Veterinary and Biomedical Sciences, Center for Molecular Immunology & Infectious Disease, The Pennsylvania State University, University Park, PA 16802, USA.
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Abstract
Tec family tyrosine kinases transduce signals from antigen and other receptors. In particular, Itk plays an important role in T-cell development and activation. Itk has an N-terminal pleckstrin homology domain, a Tec Homology domain with a proline-rich region, SH3 and SH2 domains and a kinase domain, the structure each of which has been determined. However, the full structure of Itk and other Tec kinases remain elusive. Models of Itk suggest either a head to tail dimer, with the SH2 domain interacting with the SH3 domain, or a folded monomer with the SH3 domain interacting with the proline-rich region. We show here that in vivo Itk exists as a monomer, with the pleckstrin homology domain less than 80 A from the C terminus. Zn2+ coordinating residues in the Tec Homology domain, not the proline-rich region, are critical for this intramolecular interaction. These data have implications for our understanding of Tec family kinase structure.
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Affiliation(s)
- Qian Qi
- Center for Molecular Immunology and Infectious Disease, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Yokosuka T, Saito T. Dynamic regulation of T-cell costimulation through TCR-CD28 microclusters. Immunol Rev 2009; 229:27-40. [PMID: 19426213 DOI: 10.1111/j.1600-065x.2009.00779.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
SUMMARY T-cell activation requires contact between T cells and antigen-presenting cells (APCs) to bring T-cell receptors (TCRs) and major histocompatibility complex peptide (MHCp) together to the same complex. These complexes rearrange to form a concentric circular structure, the immunological synapse (IS). After the discovery of the IS, dynamic imaging technologies have revealed the details of the IS and provided important insights for T-cell activation. We have redefined a minimal unit of T-cell activation, the 'TCR microcluster', which recognizes MHCp, triggers an assembly of assorted molecules downstream of the TCR, and induces effective signaling from TCRs. The relationship between TCR signaling and costimulatory signaling was analyzed in terms of the TCR microcluster. CD28, the most valuable costimulatory receptor, forms TCR-CD28 microclusters in cooperation with TCRs, associates with protein kinase C theta, and effectively induces initial T-cell activation. After mature IS formation, CD28 microclusters accumulate at a particular subregion of the IS, where they continuously assemble with the kinases and not TCRs, and generate sustained T-cell signaling. We propose here a 'TCR-CD28 microcluster' model in which TCR and costimulatory microclusters are spatiotemporally formed at the IS and exhibit fine-tuning of T-cell responses by assembling with specific players downstream of the TCR and CD28.
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Affiliation(s)
- Tadashi Yokosuka
- Laboratory for Cell Signaling, RIKEN Research Center for Allergy, Immunology, Yokohama, Japan
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Expression of muscarinic receptors in human and mouse sclera and their role in the regulation of scleral fibroblasts proliferation. Mol Vis 2009; 15:1277-93. [PMID: 19578554 PMCID: PMC2704914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Accepted: 06/23/2009] [Indexed: 12/04/2022] Open
Abstract
PURPOSE To determine the expression of muscarinic receptor subtypes (mAChRs) in human and mouse scleral fibroblasts (SFs), to investigate the mechanism that mediate the role mAChRs play in cell proliferation, and to explore the underlying intracellular signaling pathways involved in mouse SFs with treatment of muscarinic agents. METHODS Reverse transcription polymerase chain reaction (RT-PCR) was used to detect mRNA expression of mAChRs in the human and mouse sclera. Western blot analysis and immunocytochemistry were used to detect proteins of mAChRs in the cultured SFs. An immunohistochemical study was used to further detect the presence of mAChR proteins in frozen scleral sections. BrdU (5-bromo-2-deoxyuridine ) cell proliferation assay was performed to measure DNA synthesis. Enzyme linked immunosorbent assay (ELISA) was used to measure in vitro kinase activity for epidermal growth factor receptor (EGF-R), fibroblast growth factor (FGF-2), transforming growth factor (TGF)-beta1, and extracellular signal-regulated kinase (ERK)1/2. Expressions of epidermal growth factor-receptor (EGF-R); protein kinase C (PKC); Proline-rich tyrosine kinase 2 (Pyk-2), v-raf murine sarcoma viral oncogene homolog B1 (B-Raf), Rat Sarcoma (Ras), c-Jun N-terminal kinases (JNK1/2), and ERK1/2 were detected by immunoblot. RESULTS mAChR for subtypes M(1)-M(5) were detected in both mouse and human SFs by protein, cellular, and mRNA analysis. EGF-R, PKC, Pyk-2, B-Raf, Ras, JNK1/2, and ERK1/2 were activated after treatment by agonists and antagonists, indicated by changes in phosphorylation of these proteins. Atropine abolished the carbachol-induced activation of SF cell proliferation in a concentration-dependent manner. Carbachol also activated p42/44 mitogen-activated protein kinase (MAPK) and Ras in a time-dependent manner. Muscarinic agents also modulated fibroblast growth factor expression in these cells. CONCLUSIONS This study confirms the presence and functional role of all five mAChRs in human and mouse SFs. These results show that proliferative responses of SFs to muscarinic receptor stimulation are mediated via the activation of the classical MEK-ERK-MAPK cascade.
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Bour-Jordan H, Bluestone JA. Regulating the regulators: costimulatory signals control the homeostasis and function of regulatory T cells. Immunol Rev 2009; 229:41-66. [PMID: 19426214 PMCID: PMC2714548 DOI: 10.1111/j.1600-065x.2009.00775.x] [Citation(s) in RCA: 164] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
SUMMARY Costimulation is a concept that goes back to the early 1980s when Lafferty and others hypothesized that cell surface and soluble molecules must exist that are essential for initiating immune responses subsequent to antigen exposure. The explosion in this field of research ensued as over a dozen molecules have been identified to function as second signals following T-cell receptor engagement. By 1994, it seemed clear that the most prominent costimulatory pathway CD28 and functionally related costimulatory molecules, such as CD154, were the major drivers of a positive immune response. Then the immunology world turned upside down. CD28 knockout mice, which were, in most cases, immunodeficient, led to increased autoimmunity when bred into the non-obese diabetic background. Another CD28 family member, cytotoxic T-lymphocyte-associated protein 4, which was presumed to be a costimulatory molecule on activated T cells, turned out to be critical in downregulating immunity. These results, coupled with the vast suppressor cell literature which had been largely rebuked, suggested that the immune system was not poised for response but controlled in such a way that regulation was dominant. Over the last decade, we have learned that these costimulatory molecules play a key role in the now classical CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) that provide critical control of unwanted autoimmune responses. In this review, we discuss the connections between costimulation and Tregs that have changed the costimulation paradigm.
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Affiliation(s)
- Hélène Bour-Jordan
- UCSF Diabetes Center, University of California at San Francisco, San Francisco, CA USA
| | - Jeffrey A. Bluestone
- UCSF Diabetes Center, University of California at San Francisco, San Francisco, CA USA
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Abstract
CD28 is recognized as the primary costimulatory molecule involved in the activation of naïve T cells. However, the biochemical signaling pathways that are activated by CD28 and how these pathways are integrated with TCR signaling are still not understood. We have recently shown that there are at least two independent activation pathways induced by CD28 costimulation. One is integrated with TCR signaling in the context of the immunological synapse and is mediated through transcriptional enhancement and the second is mediated through the induction of mRNA stability. Here, we review the immunological consequences and biochemical mechanisms associated with CD28 costimulation and discuss the major questions that need to be resolved to understand the molecular mechanisms that transduce CD28 costimulation.
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Hu J, August A. Naive and innate memory phenotype CD4+ T cells have different requirements for active Itk for their development. THE JOURNAL OF IMMUNOLOGY 2008; 180:6544-52. [PMID: 18453573 DOI: 10.4049/jimmunol.180.10.6544] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The Tec family kinase Itk regulates the development of conventional and innate CD8(+) T cells. However, little is known about the role of Itk in the development of CD4(+) T cell lineages, although the role of Itk in the T cell activation and function is well defined. We show in this study that Itk null mice have increased percentage of CD62L(low)CD44(high) memory phenotype CD4(+) T cells compared with wild-type mice. These cells arise directly in the thymus, express high levels of transcripts for the T-bet and IFN-gamma and are able to produce IFN-gamma directly ex vivo in response to stimulation. Itk deficiency greatly decreases the number of CD4(+) T cells with CD62L(high)CD44(low) naive phenotype, but has no effect on the number of memory phenotype CD4(+) T cells, indicating that the development of memory phenotype CD4(+) T cells is Itk-independent. We further show that the development of the naive phenotype CD4(+) T cells is dependent on active Itk signals and can be rescued by expression of Itk specifically in T cells. Our data also show that Itk is required for functional TCR signaling in these cells, but not for the innate function in response to IL-12/IL-18 or Listeria monocytogenes stimulation. These results indicate that CD62L(high)CD44(low) "naive" CD4(+) and CD62L(low)CD44(high) "innate memory phenotype" CD4(+) T cells may be independent populations that differ in their requirement for Itk signals for development. Our data also suggest that CD4(+)CD62L(low)CD44(high) memory phenotype T cells have innate immune function.
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Affiliation(s)
- Jianfang Hu
- Center for Molecular Immunology and Infectious Disease and Department of Veterinary & Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802, USA
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Hu J, Sahu N, Walsh E, August A. Memory phenotype CD8+ T cells with innate function selectively develop in the absence of active Itk. Eur J Immunol 2007; 37:2892-9. [PMID: 17724684 PMCID: PMC2770953 DOI: 10.1002/eji.200737311] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
T cells with a memory-like phenotype and possessing innate immune function have been previously identified as CD8(+)CD44(hi) cells. These cells rapidly secrete IFN-gamma upon stimulation with IL-12/IL-18 and are involved in innate responses to infection with Listeria monocytogenes. The signals regulating these cells are unclear. The Tec kinase Itk regulates T cell activation and we report here that a majority of the CD8(+) T cells in Itk null mice have a phenotype of CD44(hi) similar to memory-like innate T cells. These cells are observed in mice carrying an Itk mutant lacking the kinase domain, indicating that active Tec kinase signaling suppresses their presence. These cells carry preformed message for and are able to rapidly produce IFN-gamma upon stimulation in vitro with IL-12/IL-18, and endow Itk null mice the ability to effectively respond to infection with L. monocytogenes or exposure to lipopolysaccharides by secretion of IFN-gamma. Transfer of these cells rescues the ability of IFN-gamma null mice to reduce bacterial burden following L. monocytogenes infection, indicating that these cells are functional CD8(+)CD44(hi) T cells previously detected in vivo. These results indicate that active signals from Tec kinases regulate the development of memory-like CD8(+) T cells with innate function.
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Affiliation(s)
- Jianfang Hu
- Center for Molecular Immunology & Infectious Disease and Department of Veterinary & Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802
- Immunology & Infectious Disease Graduate Program, The Pennsylvania State University, University Park, PA 16802
| | - Nisebita Sahu
- Center for Molecular Immunology & Infectious Disease and Department of Veterinary & Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802
- Department of Biochemistry & Molecular Biology, The Pennsylvania State University, University Park, PA 16802
| | - Elizabeth Walsh
- Center for Molecular Immunology & Infectious Disease and Department of Veterinary & Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802
- Pathobiology Graduate Program, The Pennsylvania State University, University Park, PA 16802
| | - Avery August
- Center for Molecular Immunology & Infectious Disease and Department of Veterinary & Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802
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Khurana D, Arneson LN, Schoon RA, Dick CJ, Leibson PJ. Differential regulation of human NK cell-mediated cytotoxicity by the tyrosine kinase Itk. THE JOURNAL OF IMMUNOLOGY 2007; 178:3575-82. [PMID: 17339454 DOI: 10.4049/jimmunol.178.6.3575] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
NK cells are effector lymphocytes that can recognize and eliminate virally infected and transformed cells. NK cells express distinct activating receptors, including an ITAM-containing FcR complex that recognizes Ab-coated targets, and the DNAX-activating protein of 10 kDa-containing NKG2D receptor complex that recognizes stress-induced ligands. The regulatory role of specific tyrosine kinases in these pathways is incompletely understood. In this study, we show that, in activated human NK cells, the tyrosine kinase IL-2-inducible T cell kinase (Itk), differentially regulates distinct NK-activating receptors. Enhanced expression of Itk leads to increases in calcium mobilization, granule release, and cytotoxicity upon stimulation of the ITAM-containing FcR, suggesting that Itk positively regulates FcR-initiated cytotoxicity. In contrast, enhanced Itk expression decreases cytotoxicity and granule release downstream of the DNAX-activating protein of 10 kDa-containing NKG2D receptor, suggesting that Itk is involved in a pathway of negative regulation of NKG2D-initiated granule-mediated killing. Using a kinase mutant, we show that the catalytic activity of Itk is required for both the positive and negative regulation of these pathways. Complementary experiments where Itk expression was suppressed also showed differential regulation of the two pathways. These findings suggest that Itk plays a complex role in regulating the functions initiated by distinct NK cell-activating receptors. Moreover, understanding how these pathways may be differentially regulated has relevance in the setting of autoimmune diseases and antitumor immune responses where NK cells play key regulatory roles.
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Affiliation(s)
- Dianne Khurana
- Department of Immunology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA
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Badour K, McGavin MKH, Zhang J, Freeman S, Vieira C, Filipp D, Julius M, Mills GB, Siminovitch KA. Interaction of the Wiskott-Aldrich syndrome protein with sorting nexin 9 is required for CD28 endocytosis and cosignaling in T cells. Proc Natl Acad Sci U S A 2007; 104:1593-8. [PMID: 17242350 PMCID: PMC1785243 DOI: 10.1073/pnas.0610543104] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The Wiskott-Aldrich syndrome protein (WASp) plays a major role in coupling T cell antigen receptor (TCR) stimulation to induction of actin cytoskeletal changes required for T cell activation. Here, we report that WASp inducibly binds the sorting nexin 9 (SNX9) in T cells and that WASp, SNX9, p85, and CD28 colocalize within clathrin-containing endocytic vesicles after TCR/CD28 costimulation. SNX9, implicated in clathrin-mediated endocytosis, binds WASp via its SH3 domain and uses its PX domain to interact with the phosphoinositol 3-kinase regulatory subunit p85 and product, phosphoinositol (3,4,5)P3. The data reveal ligation-induced CD28 endocytosis to be clathrin- and phosphoinositol 3-kinase-dependent and TCR/CD28-evoked CD28 internalization and NFAT activation to be markedly enhanced by SNX9 overexpression, but severely impaired by expression of an SNX9 mutant (SNX9DeltaPX) lacking p85-binding capacity. CD28 endocytosis and CD28-evoked actin polymerization also are impaired in WASp-deficient T cells. These findings suggest that SNX9 couples WASp to p85 and CD28 so as to link CD28 engagement to its internalization and to WASp-mediated actin remodeling required for CD28 cosignaling. Thus, the WASp/SNX9/p85/CD28 complex enables a unique interface of endocytic, actin polymerizing, and signal transduction pathways required for CD28-mediated T cell costimulation.
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Affiliation(s)
- Karen Badour
- *Departments of Medicine, Immunology, Medical Genetics, and Microbiology, University of Toronto, Toronto General Hospital and Samuel Lunenfeld Research Institutes, Mount Sinai Hospital, Toronto, ON, Canada M5G 1X5
| | - Mary K. H. McGavin
- *Departments of Medicine, Immunology, Medical Genetics, and Microbiology, University of Toronto, Toronto General Hospital and Samuel Lunenfeld Research Institutes, Mount Sinai Hospital, Toronto, ON, Canada M5G 1X5
| | - Jinyi Zhang
- *Departments of Medicine, Immunology, Medical Genetics, and Microbiology, University of Toronto, Toronto General Hospital and Samuel Lunenfeld Research Institutes, Mount Sinai Hospital, Toronto, ON, Canada M5G 1X5
| | - Spencer Freeman
- *Departments of Medicine, Immunology, Medical Genetics, and Microbiology, University of Toronto, Toronto General Hospital and Samuel Lunenfeld Research Institutes, Mount Sinai Hospital, Toronto, ON, Canada M5G 1X5
| | - Claudia Vieira
- *Departments of Medicine, Immunology, Medical Genetics, and Microbiology, University of Toronto, Toronto General Hospital and Samuel Lunenfeld Research Institutes, Mount Sinai Hospital, Toronto, ON, Canada M5G 1X5
| | - Dominik Filipp
- Department of Immunology, University of Toronto, Sunnybrook Research Institute, Toronto, ON, Canada M4N 3M5; and
| | - Michael Julius
- Department of Immunology, University of Toronto, Sunnybrook Research Institute, Toronto, ON, Canada M4N 3M5; and
| | - Gordon B. Mills
- Department of Molecular Therapeutics, University of Texas M. D. Anderson Cancer Center, Houston, TX 77030
| | - Katherine A. Siminovitch
- *Departments of Medicine, Immunology, Medical Genetics, and Microbiology, University of Toronto, Toronto General Hospital and Samuel Lunenfeld Research Institutes, Mount Sinai Hospital, Toronto, ON, Canada M5G 1X5
- To whom correspondence should be addressed. E-mail:
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Abstract
The Tec family of tyrosine kinases consists of five members (Itk, Rlk, Tec, Btk, and Bmx) that are expressed predominantly in hematopoietic cells. The exceptions, Tec and Bmx, are also found in endothelial cells. Tec kinases constitute the second largest family of cytoplasmic protein tyrosine kinases. While B cells express Btk and Tec, and T cells express Itk, Rlk, and Tec, all four of these kinases (Btk, Itk, Rlk, and Tec) can be detected in mast cells. This chapter will focus on the biochemical and cell biological data that have been accumulated regarding Itk, Rlk, Btk, and Tec. In particular, distinctions between the different Tec kinase family members will be highlighted, with a goal of providing insight into the unique functions of each kinase. The known functions of Tec kinases in T cell and mast cell signaling will then be described, with a particular focus on T cell receptor and mast cell Fc epsilon RI signaling pathways.
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Affiliation(s)
- Martin Felices
- Department of Pathology, University of Massachusetts Medical School, Massachusetts, USA
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43
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Qi Q, Sahu N, August A. Tec kinase Itk forms membrane clusters specifically in the vicinity of recruiting receptors. J Biol Chem 2006; 281:38529-34. [PMID: 17060314 DOI: 10.1074/jbc.m609180200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The Tec family of tyrosine kinases transduces signals from antigen and other receptors in cells of the hematopoietic system. In particular, interleukin-2 inducible T cell kinase (Itk) plays an important role in modulating T cell development and activation. Itk is activated by receptors via a phosphatidylinositol 3-kinase-mediated pathway, which results in recruitment of Itk to the plasma membrane via its pleckstrin homology domain. We show here that membrane localization of Itk results in the formation of clusters of at least two molecules within 80 A of each other, which is dependent on the integrity of its pleckstrin homology domain. By contrast, the proline-rich region within the Tec homology domain, SH3 or SH2 domains, or kinase activity were not required for this event. More importantly, these clusters of Itk molecules form in distinct regions of the plasma membrane as only receptors that recruit phosphatidylinositol 3-kinase reside in the same membrane vicinity as the recruited Itk. Our results indicate that Itk forms dimers in the membrane and that receptors that recruit Itk do so to specific membrane regions.
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Affiliation(s)
- Qian Qi
- Center for Molecular Immunology and Infectious Disease, and Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802, USA
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Hoff H, Burmester GR, Brunner-Weinzierl MC. Competition and cooperation: Signal transduction by CD28 and CTLA-4. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/sita.200500081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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45
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Stradal TEB, Pusch R, Kliche S. Molecular regulation of cytoskeletal rearrangements during T cell signalling. Results Probl Cell Differ 2006; 43:219-44. [PMID: 17068974 DOI: 10.1007/400_022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Regulation of the cytoskeleton in cells of the haematopoietic system is essential for fulfilling diverse tasks such as migration towards a chemoattractant, phagocytosis or cell-cell communication. This is particularly true for the many types of T cells, which are at the foundation of the adaptive immune system in vertebrates. Deregulation of actin filament turnover is known to be involved in the development of severe immunodeficiencies or immunoproliferative diseases. Therefore, molecular dissection of signalling complexes and effector molecules, which leads to controlled cytoskeletal assembly, has been the focus of immunological research in the last decade. In the past, cytoskeletal remodelling was frequently understood as the finish line of signalling, while today it becomes increasingly evident that actin and microtubule dynamics are required for proper signal transmission in many processes such as T cell activation. Significant effort is made in many laboratories to further elucidate the contribution of cytoskeletal remodelling to immune function. The objective of this article is to summarise the current knowledge on how actin and microtubules are reorganised to support the formation of structures as diverse as the immunological synapse and peripheral protrusions during cell migration.
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Affiliation(s)
- Theresia E B Stradal
- Signalling and Motility Group, German Research Centre for Biotechnology (GBF), Braunschweig, Germany
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46
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Bernard D, Riteau B, Hansen JD, Phillips RB, Michel F, Boudinot P, Benmansour A. Costimulatory Receptors in a Teleost Fish: Typical CD28, Elusive CTLA4. THE JOURNAL OF IMMUNOLOGY 2006; 176:4191-200. [PMID: 16547256 DOI: 10.4049/jimmunol.176.7.4191] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
T cell activation requires both specific recognition of the peptide-MHC complex by the TCR and additional signals delivered by costimulatory receptors. We have identified rainbow trout sequences similar to CD28 (rbtCD28) and CTLA4 (rbtCTLA4). rbtCD28 and rbtCTLA4 are composed of an extracellular Ig-superfamily V domain, a transmembrane region, and a cytoplasmic tail. The presence of a conserved ligand binding site within the V domain of both molecules suggests that these receptors likely recognize the fish homologues of the B7 family. The mRNA expression pattern of rbtCD28 and rbtCTLA4 in naive trout is reminiscent to that reported in humans and mice, because rbtCTLA4 expression within trout leukocytes was quickly up-regulated following PHA stimulation and virus infection. The cytoplasmic tail of rbtCD28 possesses a typical motif that is conserved in mammalian costimulatory receptors for signaling purposes. A chimeric receptor made of the extracellular domain of human CD28 fused to the cytoplasmic tail of rbtCD28 promoted TCR-induced IL-2 production in a human T cell line, indicating that rbtCD28 is indeed a positive costimulator. The cytoplasmic tail of rbtCTLA4 lacked obvious signaling motifs and accordingly failed to signal when fused to the huCD28 extracellular domain. Interestingly, rbtCTLA4 and rbtCD28 are not positioned on the same chromosome and thus do not belong to a unique costimulatory cluster as in mammals. Finally, our results raise questions about the origin and evolution of positive and negative costimulation in vertebrate immune systems.
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Affiliation(s)
- David Bernard
- Institut National de la Recherche Agronomique, Unité de Virologie et Immunologie Moléculaires, Jouy-en-Josas, France
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Ragin MJ, Hu J, Henderson AJ, August A. A role for the Tec family kinase ITK in regulating SEB-induced interleukin-2 production in vivo via c-jun phosphorylation. BMC Immunol 2005; 6:19. [PMID: 16042784 PMCID: PMC1200558 DOI: 10.1186/1471-2172-6-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Accepted: 07/22/2005] [Indexed: 12/02/2022] Open
Abstract
Background Exposure to Staphylococcal Enterotoxin B (SEB), a bacterial superantigen secreted by the Gram-positive bacteria Staphyloccocus aureus, results in the expansion and eventual clonal deletion and anergy of Vβ8+ T cells, as well as massive cytokine release, including Interleukin-2 (IL-2). This IL-2 is rapidly secreted following exposure to SEB and may contribute to the symptoms seen following exposure to this bacterial toxin. The Tec family kinase ITK has been shown to be important for the production of IL-2 by T cells stimulated in vitro and may represent a good target for blocking the production of this cytokine in vivo. In order to determine if ITK represents such a target, mice lacking ITK were analyzed for their response to SEB exposure. Results It was found that T cells from mice lacking ITK exhibited significantly reduced proliferative responses to SEB exposure in vitro, as well as in vivo. Examination of IL-2 production revealed that ITK null mice produced reduced levels of this cytokine in vitro, and more dramatically, in vivo. In vivo analysis of c-jun phosphorylation, previously shown to be critical for regulating IL-2 production, revealed that this pathway was specifically activated in SEB reactive Vβ8+ (but not non-reactive Vβ6+) T cells from WT mice, but not in Vβ8+ T cells from ITK null mice. However, toxicity analysis indicated that both WT and ITK null animals were similarly affected by SEB exposure. Conclusion These data show that ITK is required for IL-2 production induced by SEB in vivo, and may regulate signals leading IL-2 production, in part by regulating phosphorylation of c-jun. The data also suggest that perturbing T cell activation pathways leading to IL-2 does not necessarily lead to improved responses to SEB toxicity.
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Affiliation(s)
- Melanie J Ragin
- Pathobiology Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jianfang Hu
- Immunobiology Option of the Integrated Bioscience Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Andrew J Henderson
- Pathobiology Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
- Immunobiology Option of the Integrated Bioscience Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science The Pennsylvania State University, University Park, PA 16802, USA
| | - Avery August
- Pathobiology Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
- Immunobiology Option of the Integrated Bioscience Graduate Program, Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Molecular Immunology & Infectious Disease and Department of Veterinary Science The Pennsylvania State University, University Park, PA 16802, USA
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Li CR, Berg LJ. Itk is not essential for CD28 signaling in naive T cells. THE JOURNAL OF IMMUNOLOGY 2005; 174:4475-9. [PMID: 15814667 DOI: 10.4049/jimmunol.174.8.4475] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Itk, a member of the Tec family of tyrosine kinases, is critical for TCR signaling, leading to the activation of phospholipase C gamma1. Early biochemical studies performed in tumor cell lines also implicated Itk in CD28 signaling. These data were complemented by functional studies on primary Itk-/- T cells that suggested a negative role for Itk in CD28 signaling. In this report, we describe a thorough analysis of CD28-mediated responses in T cells lacking Itk. Using purified naive CD4+ T cells from Itk-/- mice, we examine a range of responses dependent on CD28 costimulation. We also analyze Akt and glycogen synthase kinase-3beta phosphorylation in response to stimulation of CD28 alone. Overall, these experiments demonstrate that CD28 signaling, as well as CD28-mediated costimulation of TCR signaling, function efficiently in the absence of Itk. These findings indicate that Itk is not essential for CD28 signaling in primary naive CD4+ T cells.
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Affiliation(s)
- Cheng-Rui Li
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655, USA
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Schwartzberg PL, Finkelstein LD, Readinger JA. TEC-family kinases: regulators of T-helper-cell differentiation. Nat Rev Immunol 2005; 5:284-95. [PMID: 15803148 DOI: 10.1038/nri1591] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The TEC-family protein tyrosine kinases ITK, RLK and TEC have been identified as key components of T-cell-receptor signalling that contribute to the regulation of phospholipase C-gamma, the mobilization of Ca(2+) and the activation of mitogen-activated protein kinases. Recent data also show that TEC kinases contribute to T-cell-receptor-driven actin reorganization and cell polarization, which are required for productive T-cell activation. Functional studies have implicated TEC kinases as important mediators of pathways that control the differentiation of CD4(+) T helper cells. Here, we review studies of signalling pathways that involve TEC kinases and how these pathways might contribute to the regulation of T-helper-cell differentiation and function.
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Affiliation(s)
- Pamela L Schwartzberg
- National Human Genome Research Institute, National Institutes of Health, 4A38/49 Convent Drive, Bethesda, Maryland 20892, USA.
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50
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Abstract
The Tec family tyrosine kinases are now recognized as important mediators of antigen receptor signaling in lymphocytes. Three members of this family, Itk, Rlk, and Tec, are expressed in T cells and activated in response to T cell receptor (TCR) engagement. Although initial studies demonstrated a role for these proteins in TCR-mediated activation of phospholipase C-gamma, recent data indicate that Tec family kinases also regulate actin cytoskeletal reorganization and cellular adhesion following TCR stimulation. In addition, Tec family kinases are activated downstream of G protein-coupled chemokine receptors, where they play parallel roles in the regulation of Rho GTPases, cell polarization, adhesion, and migration. In all these systems, however, Tec family kinases are not essential signaling components, but instead function to modulate or amplify signaling pathways. Although they quantitatively reduce proximal signaling, mutations that eliminate Tec family kinases in T cells nonetheless qualitatively alter T cell development and differentiation.
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Affiliation(s)
- Leslie J Berg
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
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